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Optimising stocking rate under commercial and subsistence pastoralism optimisering van veelading by kommersiele en bestaansveeboerdery
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: M.T. Mentis --- Department of Grassland Science,Hopes for a single criterion of overstocking are forlorn. Livestock may be kept for any of many purposes, and the stocking rate optimal for one is not necessarily so for another. Conflicts might be resolved by (1) recognising the likely... -
The performance of tropical pastures in the drier phase of the Highland sourveld of Natal
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: G.M. Brockett --- Department of Agriculture (Natal Region), N.N. Gray --- Department of Agriculture (Natal Region),Several tropical grasses (Acroceras macrum, Cenchrus ciliaris, Cyndon sp., Digitaria sp. and Pennisetum clandestinum) and legumes (Desmodium uncinatum and Lotononis bainesii) were evaluated at the Kokstad Research Station (Bioclimatic sub‐region 4f of Natal) over a period of seven years. The... -
A model for predicting long term economic optimum stocking rates for beef cattle grazing dryland pastures
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: D.I. Bransby --- Department of Grassland Science,Previous models relating profit to stocking rate have not taken into account annual variation in rainfall. A model is developed here to allow for this factor. The frequency distribution of annual rainfall is used to demonstrate how the stocking rate... -
Die wiskundige simulering van koolhidraattranslokasie in natuurlike grasveld1
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: H J Fouché --- Departement van Landbou en Watervoorsiening (Vrystaatstreek), JM De Jager --- Departement Landbouweerkunde, J Booysen --- Departement van Landbou en Watervoorsiening (Karoostreek),Die groeifunksies benodig vir die simulasie van produksie van ‘n Themeda triandra‐grasveld met behulp van die PUTU 11 simulasiemodel is ontwikkel. Vir die ontwikkeling van die model is die veldproduksiedata van die 1980/81 groeiseisoen gebruik waarna dit suksesvol, vir drie... -
Simulating browse production and response of Acacia karroo to defoliation I. Model description and sensitivity analyses
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: W.R. Teague --- , Republic of South Africa RosemaryC. Teague --- , Republic of South Africa B.H. Walker --- Department of Botany, Republic of South AfricaThe model is aimed at synthesizing existing data to enhance the understanding of this data and explore the consequences of possible browse management strategies. It gives a good reproduction of the shoot and leaf growth responses used to develop it... -
Development of a technique for assessing veld condition in the Kruger National Park using key grass species
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: W.S.W. Trollope --- Sub‐departmont Pasture Science, Faculty of Agriculture, CiskeiA technique based on key grass species was developed for assessing veld condition in the Kruger National Park in terms of its potential to produce grass forage for consumption by herbivores and fine fuels for veld burning. Fourteen grass species... -
The regrowth of Colophospermum mopane following clearing
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: R.J. Scholes --- Department of Botany, Republicof South AfricaThe recovery of cleared Colophospermum mopane thicket in the eastern Transvaal lowveld, to a level where its effect on grass production is similar to that in the pre‐cleared state, occurs within fourteen years. Based on certain assumptions, the ‘effective duration’... -
Simulating browse production and response of Acacia karroo to defoliation II. Evaluation of browse management systems and strategies
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: W.R. Teague --- , Republic of South Africa B.H. Walker --- Centre for Resource Ecology, Republic of South AfricaTo assess management implications, a model was used to simulate the response of Acacia karroo to a wide range of different climatic patterns and defoliation regimes. The model predicts that if poor growing conditions initiate growth later in spring than... -
Remote sensing applications for monitoring rangeland vegetation
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: P.T. Tueller --- Department of Range, Wildlife and Forestry, United States of AmericaRemote sensing techniques hold considerable promise for the inventory and monitoring of natural resources on range‐lands. A significant lack of information concerning basic spectral characteristics of range vegetation and soils has resulted in a lack of rangeland applications. To use... -
Relations between woody and herbaceous components and the effects of bush‐clearing in southern African savannas
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: W.R. Teague --- , Republic of South Africa G.N. Smit --- , Republic of South AfricaThe relations between woody and herbaceous plants in southern African savannas are reviewed in the context of pastoral use. Current knowledge is summarized, important gaps are indicated and research priorities are suggested. Although all savannas consist of a grass and... -
Plant species dynamics in the Southern Tall Grassveld under grazing, resting and fire
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: C.D. Morris --- Department of Grassland Science, Republic of South Africa N.M. Tainton --- Department of Grassland Science, Republic of South Africa M.B. Hardy --- Department of Agricultural Development (Natal Region), Republic of South AfricaAn analysis of temporal changes in botanical composition in a long‐term grazing trial indicates that species dynamics in the Southern Tall Grassveld of Natal are determined by the specific combination of grazing, mowing and fire impacts. Species composition of a... -
Influence of temperature and daylength on the phenological development of annual Medicago species with particular reference to M. truncatula, cv. Jemalong
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.M. van Heerden --- Department of Agriculture,In a glasshouse and two growth-room trials, carried out in conjunction with 12 serial plantings in pots in the open, it was found that the phenological development of Medicago truncatula, M. tornata, M. aculeata, M. polymorpha, M. scutellata and M... -
Assessment of recent drought severity for natural grassland at three locations
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.A. Dyer --- Crop Production Division, Canada J.M. de Jager --- Department of Agrometeorology, Republic of South AfricaThe relative severity of drought in natural grassland during three growing seasons was analyzed for three South African weather stations. Computer simulation of grassland water use, based upon weather records, was used to quantify drought and to compare the conditions... -
Soils derived from granite in two Mt. Garnet toposequences, North Queensland, Australia
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: E. Verster --- Department of Geography, Republic of South AfricaTwo toposequences derived from granite in the Mt. Garnet area, North Queensland, were examined to determine the detailed soil - landform relationships in order to facilitate subsequent broad-scale mapping of the soil resource. The dominant landsurface feature is gently sloping,... -
Preliminary evaluation of two maize (Zea mays L.) growth-simulation models
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: R.N. de Vos --- , Republic of South Africa J.B. Mallett --- , Republic of South AfricaTwo maize growth-simulation models developed in the U.S.A., CERES-Malze and CORNF, were evaluated with South African data using graphical and numerical techniques. The results indicate that both models agree well with observed values of total above-ground plant dry mass, leaf... -
Risk analysis of wheat production in the central Orange Free State using a growth model
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- Department of Agrometeorology, Republic of South Africa J.M. de Jager --- Department of Agrometeorology, Republic of South AfricaA wheat crop growth model (Singels, 1983) was refined and used to calculate annual grain yield from weather data for 45 seasons in the Bloemfontein area. Five different levels of profile-available water capacity were used as soil input parameter. Other... -
Typifying late-season weather for maize yield prediction
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: B. St. E. Clemence --- , Republic of South Africa J.B. Mallett --- , Republic of South AfricaLong-term weather data were used to generate typical weather records. By substituting typical weather data for actual late-season weather data it was possible to compute yield predictions using the model CERES-Maize, and compare these with predictions based on full season... -
Voorspelling van nitraatbeweging in 'n fynsandleemgrond gedurende die braakperiode met die Burnsmodel
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: E.J. Haumann --- Departement van Grondkunde, Republiek van Suid-Afrika C.C. du Preez --- Departement van Grondkunde, Republiek van Suid-Afrika'n Eenvoudige model wat deur Burns (1974) ontwikkel is vir die voorspelling van nitraatbeweging in sandtot sandleemgronde is getoets. Verskillende nitraatverspreidingspatrone is in 'n fynsandleemgrond van 1,5-m diepte tot stand gebring waarna water met mikrobesproeiing toegedien is om nitraatbeweging te... -
Spatial pattern and variability of soil and hillslope properties in a granitic landscape 1. Pretoriuskop area
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.C. Munnik --- Department of Geography, Republic of South Africa E. Verster --- Department of Geography, Republic of South Africa T.H. van Rooyen --- Department of Geography, Republic of South AfricaCharacteristics of nine hillslope profiles and selected properties of 69 soil profiles were determined in order to evaluate the spatial pattern and variability of soil and hillslope properties in a granitic area near Pretoriuskop, Kruger National Park. A transect design... -
A simple method for supplementing long-term weather records in a maize-modelling exercise
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: B. S.E. Clemence --- , Republic of South AfricaMissing weather data is a very real problem when using daily-incrementing crop growth simulation models. This is especially true in the case of daily air temperature and solar radiation data. The aim of this study was to compare two simple... -
Refinement and validation of the PUTU wheat crop growth model 1. Phenology
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- Department of Agrometeorology, Republic of South Africa J.M. de Jager --- Department of Agrometeorology, Republic of South AfricaThe phonological submodel of the PUTU wheat crop growth model was refined to account for the variation in sensitivity to vernalization and photoperiod. Crop development rate was simulated in five phenological phases making use of temperature and photoperiod. Base values... -
Refinement and validation of the PUTU wheat crop growth model 2. Leaf area expansion
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- Department of Agrometeorology, Republic of South Africa J.M. de Jager --- Department of Agrometeorology, Republic of South AfricaA refined leaf growth submodel was incorporated in an existing wheat crop growth model. The submodel calculated daily green leaf area expansion per plant by taking into account plant population, crop age, interplant competition, temperature and crop water status. After... -
Refinement and validation of the PUTU wheat crop growth model 3. Grain growth
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- Department of Agrometeorology, Republic of South Africa J.M. de Jager --- Department of Agrometeorology, Republic of South AfricaA submodel for simulating daily grain growth was incorporated in an existing wheat crop growth model. The submodel calculated daily potential grain growth from green leaf area index, plant population and crop stage. Simulated daily potential grain growth was reduced... -
A growth model for sugar-cane based on a simple carbon balance and the CERES-Maize water balance
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N.G. Inman-Bamber --- , Republic of South AfricaThe economic optimum harvest age for sugar-cane depends to a large extent on how rates of photosynthesis and respiration change with age. A simple model of the carbon balance in which a constant photosynthetic efficiency was assumed, accounted to a... -
Evaluating different wheat production strategies for the Orange Free State using stochastic dominance techniques and a crop growth model
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- Department of Agrometeorology, Republic of South Africa J.M. de Jager --- Department of Agrometeorology, Republic of South AfricaA wheat crop growth model and stochastic dominance techniques were used to evaluate several wheat production strategies for the Orange Free State. Fifty seasonal grain yields and corresponding gross margins were calculated from daily weather data and soil data for... -
A family of stochastic models for droughts
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: W. Zucchini --- Department of Statistical Sciences, Republic of South Africa P.T. Adamson --- , United Kingdom L. McNeill --- Department of Statistical Sciences, Republic of South AfricaThere is no single quantitative definition of a drought; what constitutes a drought depends both on water needs and on storage capabilities. In this paper a family of models is proposed which is sufficiently flexible to cover a range of... -
An attempt at estimating solar radiation at South African sites which measure air temperature only
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: B. S.E. Clemence --- , Republic of South AfricaDaily potential surface radiation values were calculated for selected South African weather stations. These were used, together with various air temperature parameters, to derive regression equations to estimate actual surface solar radiation at sites lacking the required instrumentation. A single... -
Spatial pattern and variability of soil and hillslope properties in a granitic landscape 2. Pretoria—Johannesburg area
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.C. Munnik --- Department of Geography, Republic of South Africa E. Versterand --- Department of Geography, Republic of South Africa T.H. van Rooyen --- Department of Geography, Republic of South AfricaUsing a transect design, a detailed examination was made of nine hillslopes and 64 soil profiles in the granitic area between Johannesburg and Pretoria to assess the spatial pattern and variability of soil and hillslope properties. The land surface was... -
The success of the AMMI model in predicting lucerne yields for cultivars with differing dormancy characteristics
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: MarieF. Smith --- , Republic of South Africa A. Smith --- , Republic of South AfricaThe AMMI model, which incorporates both additive and multiplicative components into an integrated, powerful, least squares analysis, is used for the analysis of cultivar trials at different localities. These trials are a major experimental component in crop production and plant... -
Thermal time bias in maize growth simulation due to mesoscale weather effects
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: W. A.J. Berry --- , Republic of South Africa B. S.E. Clemence --- , Republic of South AfricaThe effect of cold air advection on the estimates of daily thermal time with a base temperature of 8°C (DTT8), calculated using maximum and minimum screen temperatures (max./min. values), was examined. Screen temperature data for at least three maize-growing seasons... -
AMMI analysis of potato cultivar yield trials
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.J. Steyn --- , Republic of South Africa A.F. Visser --- , Republic of South Africa MarieF. Smith --- , Republic of South Africa J.L. Schoeman --- , Republic of South AfricaPotatoes, Solanum tuberosum (L), are cultivated in South Africa under a variety of different climates and seasons. The wide environmental variation encountered and the confirmed occurrence of genotype-environmental interaction necessitates the use of criteria, other than averages, in the evaluation... -
Bepaling van optimale blom en plantdatums vir koring in die sentrale besproeiingsgebiede van die RSA met behulp van 'n groeimodel
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- Departement Landbouweerkunde, Republiek van Suid-AfrikaOptimale blom- en plantperiodes vir besproeiingskoring is bepaal vir 15 lokaliteite in die sentrale besproeiingsgebiede van die RSA deur gebruik te maak van historiese temperatuurdata en die PUTU koringgroeimodel. Die hoogste gemiddelde opbrengs is gesimuleer met blomperiodes wat oor die... -
Evaluering en kalibrering van CERES-Maize. 1. Nie-lineêre regressie om genetiese parameters te bepaal
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.S. du Toit --- , Republiek van Suid-Afrika P.J. van Rooyen --- , Republiek van Suid-Afrika J.J. Human --- Departement Agronomie, Republiek van Suid-AfrikaDie genetiese parameters van die meeste plaaslike mielie cultivars wat as inset van CERES-Maize benodig word, is nog nie bepaal nie. Sodanige parameters kan met behulp van bestaande oesdata en fenologiese datums, uit veldproewe afgelei word. Programmatuur kan gebruik word... -
Simulation of main stem mature leaf area of maize
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- Department of Agrometeorology, Republic of South Africa J.M. de Jager --- Department of Agrometeorology, Republic of South AfricaThe accuracy of different models for simulating the area of mature leaves on the main stem (PLA) of maize using thermal time was investigated. The accuracy of sub-models for simulating the area of individual mature leaves (LAn) and the number... -
Spatial pattern and variability of soil and hillslope properties in a granitic landscape. 3. Phalaborwa area
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.C. Munnik --- Department of Geography, Republic of South Africa E. Verster --- Department of Geography, Republic of South Africa T.H. van Rooyen --- Department of Geography, Republic of South AfricaA pedogeomorphic study was made of the area immediately east of Phalaborwa underlain by granitic materials. Fifty-five soil profiles from nine transects were examined in detail to determine, among other things, the spatial variability of the soils and the hillslope... -
Simple regression models for the qualitative prediction of atrazine and terbuthylazine leaching
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. Reinhardt --- Department of Plant Production and Soil Science, South Africa K.J. Hugo --- Department of Plant Production and Soil Science, South AfricaLeaching of atrazine [6-chloro-N-ethyf-N′-(methylethyl)-1,3,5-triazine-2,4-dlamine] and terbuthylazine [6-chloro- N-(1,1-dirnelhylethyt)-N′-ethyl-1,3,5-triazlne-2,4-diamine] was studied in 23 soils by means of the soil thick-layer leaching method. The equivalent of 4 kg ai ha−1 of both herbicides was leached with water equivalent to 129 mm rain... -
A technique to evaluate ENSO-based maize production strategies
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- Department of Agrometeorology, South Africa A.B. Potgieter --- Free State Department of Agriculture and Environmental Affairs, South AfricaDrought occurs frequently in southern Africa, which causes harm to crop production and food security. Atmospheric and oceanic phenomena such as EL Niño/Southern Oscilation (ENSO) may be used to forecast drought. Crop production strategies could then be adapted to mitigate... -
Calibration of CERES3 (Maize) to improve silking date prediction values for South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.S. du Toit --- , Republic of South Africa J. Booysen --- , Republic of South Africa J.J. Human --- Department of Agronomy, Republic of South AfricaSilking which coincides with the mid-summer drought in South Africa, could have a significant negative effect on maize yield. Errors in the prediction of silking date could contribute to errors in kernel number simulation, and consequently to errors in yield... -
The relationship between ENSO and rainfall and yield in the South African sugar industry
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- Department of Agronomy, Republic of South Africa C.N. Bezuidenhout --- Department of Agronomy, Republic of South AfricaInformation on the effects of El Nino on local climate and sugarcane production will assist planning and management. The objective of this study was to investigate the relationship between the southern oscillation index (SOI) and rainfall and sugarcane yields in... -
Application of Empirical Soil Loss Models in southern Africa: a review
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.J. Smith --- , Republic of South AfricaEmpirical soil loss models are relatively simple and have been applied in many parts of the world. The application of the Soil Loss Estimation Model for Southern Africa (SLEMSA), the Universal Soil Loss Equation (USLE) and the Revised Universal Soil... -
Genotype × environment interaction of winter wheat (Triticum aestivum L.) in South Africa: I. AMMI analysis of yield performance
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.L. Purchase --- , Republic of South Africa Hesta Hatting --- , Republic of South Africa C.S. van Deventer --- Department of Plant Breeding, Republic of South AfricaThirteen winter and intermediate type bread wheat cultivars were evaluated under dryland conditions over a four year period from 1991 to 1994 and over 120 environments in the Free State province of South Africa. The Additive Main Effects and Multiplicative... -
Genotype × environment interaction of winter wheat (Triticum aestivum L.) in South Africa: II. Stability analysis of yield performance
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.L. Purchase --- , Republic of South Africa Hesta Hatting --- , Republic of South Africa C.S. van Deventer --- Department of Plant Breeding, Republic of South AfricaThirteen winter and intermediate type bread wheat cultivars were evaluated for yield stability under dryland conditions over a four year period from 1991 to 1994 and over a total of 120 environments in the Western, Central and Eastern Free State... -
Calibration and validation of the SWB model for sunflower (Helianthus annuus L.)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N.Z. Jovanovic --- Department of Plant Production and Soil Science, Republic of South Africa J.G. Annandale --- Department of Plant Production and Soil Science, Republic of South Africa A.A. Nel --- , Republic of South AfricaThe Soil Water Balance (SWB) generic crop growth and irrigation scheduling model was used to simulate the crop growth and soil water balance of sunflower (Helianthus annuus L. c v. CAR 1199 and SO 306) grown at Rietrivier. The objectives... -
Calibration and validation of the SWB irrigation scheduling model for soybean [Glycine max. (L.) Merr., indeterminate cv. Wayne]
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N.Z. Jovanovic --- Department of Plant Production and Soil Science, South Africa J.G. Annandale --- Department of Plant Production and Soil Science, South Africa A. T.P. Bennie --- Department of Soil Science, South AfricaSoil Water Balance (SWB) is a mechanistic, irrigation scheduling, generic crop model including a database of crop specific growth parameters. The objective of this study was to calibrate and validate this model for soybean [Glycine max. (L.) Merr., indeterminate cv... -
Water balance simulation of a peach orchard using the SWB model
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N. du Sautoy --- Dept. of Soil Science, Faculty of Agriculture, Republic of South Africa N.Z. Jovanovic --- Dept. of Plant Production and Soil Science, Republic of South Africa J.G. Annandale --- Dept. of Plant Production and Soil Science, Republic of South AfricaSoil Water Balance (SWB) is a user-friendly irrigation scheduling model developed to estimate water use for a wide range of crops. The FAO crop factor option within this model allows one to determine daily irrigation requirements from daily weather data... -
CLIMGEN-UP: A user-friendly weather data generator
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N.Z. Jovanovic --- Department of Earth Sciences, South Africa J.G. Annandale --- Department Plant Production and Soil Science, South Africa N. Benadè --- , South Africa G.S. Campbell --- , USAUser-friendly Windows software, CLIMGEN-UP, was developed based on the CLIMGEN weather data generator. CLIMGEN-UP calculates and stores monthly statistical parameters, based on historic data of daily rainfall, minimum and maximum temperature. It can then generate and store long-series of daily... -
A study of the kinetics of the adsorption of phosphorus by selected South African soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.C. Henry --- , MarieF. Smith --- ,Plots of the decline of the concentration of phosphorus in soil suspensions over time were constructed for 23 selected soils from South Africa and, using non-linear regression analysis, various models were fitted to the time curves, including mechanistic first and... -
Modelling the contribution of root accessible water tables towards crop water requirements
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N.Z. Jovanovic --- Department of Earth Sciences, Republic of South Africa L. Ehlers --- Department of Soil, Republic of South Africa A. T.P. Bennie --- Department of Soil, Republic of South Africa C.C. Du Preez --- Department of Soil, Republic of South Africa J.G. Annandale --- Department Plant Production and Soil Science, Republic of South AfricaProper utilization of shallow water tables could substantially reduce irrigation water requirements in large agricultural areas. The objective was to develop and test a computer model for predicting the contribution of shallow water tables to root water uptake. The model... -
Development of a simple empirical model for predicting maize yields in a semi-arid area
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: T.B. Zere --- Department of Soil, Republic of South Africa C.W. van Huyssteen --- Department of Soil, Republic of South Africa M. Hensley --- Department of Soil, Republic of South AfricaA yield prediction model is necessary, together with long-term climate data, to calculate the long-term yields needed for making a quantitative productivity evaluation of a crop ecotope in the form of a cumulative probability function (CPF). In this study the... -
Analysis of Spray Aid's residue curve for timing fungicide applications for grey leaf spot on maize
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N.C. van Rij --- , South Africa N.W. Quinn --- , South Africa P.M. Caldwell --- , South Africa M.J. Savage --- , South AfricaMaize grey leaf spot is still a problem in commercial maize production, although the effect has been reduced with the widespread use of resistant varieties. It is estimated that, with a yield reduction of 1 %, annual economic losses of... -
Stability analysis of grain yield of tef (Eragrostis tef) using the mixed model approach
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: L.D. Kassa --- Discipline of Statistics & Operations Research, Republic of South Africa MarieF. Smith --- Biometry Unit, Republic of South Africa H. Fufa --- , EthiopiaMulti-environment trials are usually used to assess the grain yield stability of genotypes. Most of the common stability measures such as Finlay and Wilkinson (1963), Eberhart and Russell (1966) and Shukla (1972), can be accommodated by a linear mixed model... -
Statistical evaluation of the germination of Cleome gynandra L. seeds
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.O. Ochuodho --- , South Africa A.T. Modi --- , South AfricaRadicle protrusion and subsequent seedling establishment are two ways of defining seed germination. However, international rules for testing seeds adopted the first and final counts through consensus as defining stages of seed germination. In this study statistical guidelines have been... -
Predicting the effects of nitrogen and planting density on maize water use in semi-arid Kenya
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. B.O. Ogola --- Department of Plant Production, South Africa T.R. Wheeler --- Department of Agriculture, U.K. P.M. Harris --- Department of Agriculture, U.K.Models are important tools to assess the scope of management effects on crop productivity under different climatic and soil regimes. Accordingly, this study developed and used a simple model to assess the effects of nitrogen fertiliser and planting density on... -
A canning quality model for small white bean lines selected for breeding (Phaseolus vulgaris L.)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M. van der Merwe --- , South Africa G. Osthoff --- Department of Microbial, 9300 South Africa A.J. Pretorius --- , South AfricaThe study aimed to validate canonical variate analysis (CVA) model equations for the grouping of small white beans according to canning quality by testing them on four cultivar samples of known canning quality (2000/01 season), and 24 breeding samples that... -
Comparison between traditional and scientific irrigation scheduling practices for furrow irrigated potatoes (Solanum tuberosum L.) in Ethiopia
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: EB Geremew --- Department of Plant Production and Soil Science, South Africa JM Steyn --- Department of Plant Production and Soil Science, South Africa JG Annandale --- Department of Plant Production and Soil Science, South AfricaTraditional irrigation schemes constitute about 40% of the total irrigated land in Ethiopia. Despite this, the sector has been overlooked and not supported by improved water management technologies. A survey conducted on one of the schemes, Godino, indicated that farmers... -
Relations between phosphorus retention parameters and some other properties of benchmark soils in Lesotho
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: S.F. Molete --- Department of Soil, Crop and Climate Sciences, South Africa C.C. du Preez --- Department of Soil, Crop and Climate Sciences, South Africa M.V. Marake --- , LesothoThe benchmark soils of Lesotho are characterized by high P retention and this aspect should be accommodated in fertilization programmes. This together with long procedures for determination of P retention parameters and a lack of information on the relations between... -
Additive mean effects and multiplicative interaction analysis of maize yield trials in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: S. H. Ma’ali --- , South AfricaThirty five maize hybrids were evaluated over 98 environments for genotype x environment interaction (GEI) and yield stability under dry land conditions during the 2003 to 2006 seasons in the eastern and western maize production regions of South Africa. The... -
Soil water variability in the Weatherley grassland catchment, South Africa: II. Soil water content
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: CW van Huyssteen --- Department of Soil, Crop and Climate Sciences, South Africa TB Zere --- Department of Soil, Crop and Climate Sciences, South Africa M Hensley --- Department of Soil, Crop and Climate Sciences, South AfricaSoil water content is a major factor that affects the hydrological response of a hillslope or catchment. It is therefore important to have reliable soil water content data to estimate catchment water yield. Daily soil water content (θ) data was... -
FAO-type crop factor determination for irrigation scheduling of hot pepper (Capsicum annuum L.) cultivars
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Y.A. Alemayehu --- Department of Plant Production and Soil Science, South Africa J.M. Steyn --- Department of Plant Production and Soil Science, South Africa J.G. Annandale --- Department of Plant Production and Soil Science, South AfricaHot pepper (Capsicum annuum L.) is an irrigated, high value cash crop. Irrigation requirements can be estimated following a FAO crop factor approach, using information on basal crop coefficients (Kcb), crop coefficients (Kc) and duration of crop growth stages. However,... -
Obtaining the parameters required to model labile phosphorus for South African soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M. Van der Laan --- Department of Plant Production and Soil Science, South Africa J.G. Annandale --- Department of Plant Production and Soil Science, South Africa C.C. du Preez --- Department of Soil, Crop and Climate Sciences, South Africa S.A. Lorentz --- , South AfricaModelling phosphorus (P) in the environment can increase our understanding of potential transfer pathways into receiving water bodies as well as the plant availability of this nutrient in soil. Many current models make use of algorithms originally developed for the... -
Modelling crop growth and crop water relations in South Africa: Past achievements and lessons for the future
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- , South Africa J.G. Annandale --- Department of Plant Production and Soil Science, South Africa J.M. De Jager --- Department of Soil, Crop and Climate Sciences, South Africa R.E. Schulze --- , South Africa N.G. Inman-Bamber --- , Australia W. Durand --- , South Africa L.D. Van Rensburg --- Department of Soil, Crop and Climate Sciences, South Africa P.S. Van Heerden --- , South Africa C.T. Crosby --- , South Africa G.C. Green --- , South Africa J.M. Steyn --- Department of Plant Production and Soil Science, South AfricaMathematical simulation of crop growth and water relations has become indispensable to agricultural science and practice. A critical assessment of how modelling has contributed to the development of crop science and to the management of crop production and natural resources... -
Targeting of early to intermediate maize hybrids for yield performanceand yield stability using SREG model
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.S. Setimela --- , Zimbabwe J. Crossa --- CIMMYT Km, D.F Mexico M. Bänziger --- CIMMYT Km, D.F MexicoThe effectiveness of targeting and predicting maize (Zea mays.L) hybrid performance is difficult when the magnitude of genotype x environment (GE) interaction and yield prediction cannot be interpreted and is only based on genotypes (G) and GE means. The traditional... -
Disaggregation of land types using terrain analysis, expert knowledge and GIS methods
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: George M van Zijl --- Department of Soil, Crop and Climate Science, South Africa Pieter Al Le Roux --- Department of Soil, Crop and Climate Science, South Africa David P Turner --- Agricultural Research Council–Institute for Soil, Climate and Water, South AfricaSoil maps’ value is increasingly recognised for enabling the optimal management of ecosystems. Digital soil mapping (DSM) can overcome the cost constraints of traditional mapping methods, but requires local area-specific research. As South Africa is blessed with the land type... -
Chickpea residue properties controlling decomposition dynamics and nitrogen availability in some tropical acid soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Benjamin O Danga --- Department of Agricultural Resource Management, Kenya Aviva Hadas --- Department of Soil Chemistry and Plant Nutrition, Israel Isaiah IC Wakindiki --- Department of Agronomy, South Africa Josephine P Ouma --- Department of Crops, Horticulture and Soils, Kenya Asher Bar-Tal --- Department of Soil Chemistry and Plant Nutrition, IsraelChickpea (Cicer arietinum) grown in a rotation can contribute significant nitrogen (N) if its decomposition and nutrient-release dynamics are known and synchronised with the maximum demand by the succeeding crop. The aims of the study were to investigate the decomposition... -
Assessment of the monkfish Lophius vomerinus resource off Namibia
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: L. Maartens A. J. BoothThe Lophius vomerinus component of the monkfish resource off Namibia was assessed by means of deterministic length- and age-based models. Steady state length cohort analyses illustrated that, although the model was sensitive to the rate of natural mortality, it was... -
Quantifying commercial catch and effort of monkfish Lophius vomerinus and L. vaillanti off Namibia
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: L. Maartens A. J. BoothAbundance and exploitation patterns of monkfish Lophius vomerinus and L. vaillanti were investigated for use as inputs into a stock assessment framework to be used for management of the Namibian monkfish resource. Total numbers of monkfish caught per size-class were... -
An assessment of the current status and potential yield of Namibia's northern West Coast steenbras Lithognathus aureti population
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: J. A. Holtzhausen C. H. KirchnerTwo distinct populations of West Coast steenbras Lithognathus aureti are found in Namibian waters; one, the northern population, is exploited recreationally and commercially. Data collected between 1995 and 1999 were used to evaluate its current state and potential yield, using... -
Trap selectivity and the effects of altering gear design in the South African rock lobster Jasus lalandii commercial fishery
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: D. S. Schoeman A. C. Cockcroft D. L. Van Zyl P. C. GoosenThe current trap fishery for the West Coast rock lobster Jasus lalandii in South African waters results in the capture, sorting and release of large numbers of undersized animals. Once removed from the water, they are vulnerable to damage from... -
GLM-based standardization of the catch per unit effort series for South African west coast hake, focusing on adjustments for targeting other species
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: J. P. Glazer D. S. ButterworthCatch per unit effort (cpue) data for the South African west coast Cape hakes Merluccius capensis and M. paradoxus were standardized by applying the Generalized Linear Modelling (GLM) technique. The resulting standardized series indicated that resource abundance declined at a... -
A CONCEPTUAL MODEL OF A SILTATION SYSTEM IN SHALLOW LAKES WITH LITTORAL VEGETATION
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: P.J. Weisser --- Facultad de Ciencias,In shallow lakes a siltation system develops when wind driven water turbulence erodes the lake floor, silt is resuspended and transported by means of waterdrift into the littoral vegetation. Here, due to the resistance of the vegetation, the turbulence is... -
LIMNOLOGICAL MODELLING: SIMULATION OF VERTICAL PROFILES OF TEMPERATURE, DISSOLVED OXYGEN AND NUTRIENTS. I. THEORY
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: B. Henderson-Sellers --- Department of Civil Engineering, United KingdomIn a body of water, variations occur in all limnological parameters on many time and space scales. Modelling can either be specific - for a selected subset; or can attempt to simulate the gross characteristics of e.g. current, temperature, algal... -
PHOSPHORUS DYNAMICS IN THE MONIMOLIMNION OF SWARTVLEI
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: M.J. Silberbauer --- , South AfricaThe exchange of phosphorus between the bottom sediment and monimolimnion of Swartvlei, a meromictic, humic lake, was investigated during the last three months of 1980. The concentrations of oxygen, dissolved salts, phosphorus and Fe++ in the water column were monitored,... -
PREDICTION OF SURFACE WATER TEMPERATURE OF SOUTH AFRICAN IMPOUNDMENTS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.J. van Schalkwyk --- Department of Mathematical Statistics, Republic of South Africa R.D. Walmsley --- Department of Plant Schiences, Republic of South AfricaTemperature data for 18 South African impoundments were evaluated against Straskraba's global surface water predictive model. All impoundments exhibited quantifiable sinusoidal annual temperature variations which allowed for good predictive capabilities using Straskraba's empirical approach. For each impoundment coefficients for input... -
PRODUCTION OF THE AFRICAN CATFISH (CLARIAS GARIEPINUS) II. POPULATION PRODUCTION AS ESTIMATED FROM SURPLUS PRODUCTION MODELS FOR LAKE MCILWAINE, ZIMBABWE
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: Douglas Clay --- Marine Fish Division, Department of Fisheries and Oceans, CanadaThe population production of Clarias gariepinus was studied by Schaefer type surplus production models. The maximum sustainable yield of African catfish in Lake McIlwaine, Zimbabwe was found to be in the range of 33 000 to 41 000 kg (13,46... -
NUTRIENTS AND THE PRODUCTIVITY OF ESTUARINE AND COASTAL MARINE ECOSYSTEMS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: S.W. Nixon --- Marine Ecosystems Research Laboratory, United States of America C.A. Oviatt --- Marine Ecosystems Research Laboratory, United States of America J. Frithsen --- Marine Ecosystems Research Laboratory, United States of America B. Sullivan --- Marine Ecosystems Research Laboratory, United States of AmericaRecent research on estuarine and coastal marine systems has revealed two particularly interesting things about nutrients and productivity. First is the observation that these areas are among the most intensively fertilized environments on earth. Second is the common finding that... -
THE USE OF MICROCOMPUTERS IN WATER RESOURCE MODELLING
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: W. J.R. Alexander --- Department of Civil Engineering,Microcomputers are the ideal tool for water resource modelling. Not only are they fast and computationally efficient, but they can also provide the user with dynamic graphical displays which greatly assist in the interpretation of the results of the analyses... -
MODELS OF ECOSYSTEMS AND AQUATIC ENVIRONMENTS: DEVELOPMENT AND APPLICATION
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: B.R. Allanson --- , South AfricaAn historical treatment of a number of principal events is given. This leads to an assessment of the current research approach in hydrobiology and its success in the development of process orientated ecosystem component models. With the contemporaneous development of... -
A RULE-BASED ECOSYSTEM MODEL FOR THE MANAGEMENT OF LAKE ST LUCIA
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: R.H. Taylor --- Natal Parks Board, South Africa B.P. Farm --- Dept. of Ecology and Behavioural Biology, United States of America A.M. Starfield --- Dept. of Ecology and Behavioural Biology, United States of AmericaLand transformations in the catchments of Lake St Lucia have altered the hydrology of the system and increased management is now needed to counteract these changes. There are several management options available, but prior to implementing them we must be... -
APPLICATION OF LAVSOE, AN EUTROPHICATION MODEL, TO BLOEMHOF DAM
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.N. Rossouw --- ,In 1985 the Department of Water Affairs introduced an effluent phosphate standard of 1 mg l−1 (as P) in seven potentially sensitive catchments. Although this is an uniform standard, permits can be granted for effluents to exceed the standard in... -
WATER QUALITY MODELLING PERCEPTIONS OF A WATER RESOURCE MANAGEMENT ORGANIZATION
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: H.D. Furness --- Scientific Services Division, South Africa W.N. Richards --- Scientific Services Division, South AfricaThe use of models by the South African water industry is discussed. It is suggested that climatic conditions and existing legislation have influenced the formulation of models. Future model requirements by the water Industry are outlined. Changes are suggested which... -
FUTURE CHALLENGES IN WATER QUALITY MODELLING WITH PARTICULAR REFERENCE TO OPERATIONALLY CLOSED CATCHMENTS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: S.F. Forster --- Department of Water Affairs, South Africa F.A. Stoffberg --- Department of Water Affairs, South Africa J.A. van Rooyen --- Department of Water Affairs, South AfricaAs a result of the declining quality of many water sources, the use of water quality models in planning is increasing. To date applications have involved the simulation of total dissolved salts and nutrients, largely in catchments affected by urban... -
Evaluation of a Computer Model for the Selection of Candidate Species for Aquaculture
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: Peter A. Cook --- Zoology Department, South Africa R.D. Walmsley --- , South AfricaThe use of a computer-based “Expert Choice” system, incorporating the Analytical Hierarchy Process, in the selection of candidate species for aquaculture is described. The system is considered to be particularly useful in developing countries or areas where the aquaculture industry... -
Development of a ground truthing method for determination of rangeland biomass using canopy reflectance properties
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: L. GerberVeld condition assessment and establishment of grazing capacity norms provide guidelines for the formulation of sustainable practices. However, conventional monitoring methods are becoming inadequate to meet future challenges, where quantification of spatial and temporal variation is required. This study proposes... -
Production and physiological responses of Italian ryegrass and white clover grown in monocultures and mixed stands
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: L. Gerber J.J. GerberRyegrass and clover, when grown under optimal conditions in mixed stands interact in response to available light energy. With other resources non-limiting, pasture production is determined by the efficiency with which solar radiation is intercepted by canopies and converted into... -
Predicting the extent of succulent thicket under current and future climate scenarios
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: MP Robertson AR PalmerUsing data from the distribution records of the facultative CAM succulent shrub Portulacaria afra, and high resolution climate response surfaces, we developed a spatially explicit model of the potential distribution of the species in the Thicket Biome of the eastern... -
Monitoring in a complex world — seeking slow variables, a scaled focus, and speedier learning
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: T.J.P. Lynam M. Stafford SmithRecent developments from complex systems theorists provide new insights into our understanding and, hence, monitoring of rangelands. Designing monitoring systems around the slow variables should lead to the generation of information that could greatly improve decision making in an adaptive... -
Rangeland assessment and monitoring: the elusive elixir
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: P.J.K. Zacharias'Classical' rangeland monitoring is discussed in the context of its fitness-for-purpose. The theoretical or descriptive models that underpin global approaches are considered and reviewed. The needs and types of measurements are discussed as are developments in southern Africa over three... -
Lines around fragments: effects of fencing on large herbivores
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: RandallB Boone N Thompson HobbsPeople construct fences to delineate land ownership and to control access to land. Fences accomplish several purposes, notable among these are containing livestock or wildlife raised for profit or subsistence, excluding use of vegetation within areas to be conserved and... -
Climate variability and impacts on east African livestock herders: the Maasai of Ngorongoro Conservation Area, Tanzania
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: KathleenA Galvin PhilipK Thornton RandallB Boone Jennifer SunderlandEast African pastoral adaptation and vulnerability to climate variability and climate change is assessed, using data from decisionmaking processes and ecological data of the Maasai of Ngorongoro Conservation Area as an example. The paper uses integrated modeling, linking PHEWS, a... -
Analysis of factors affecting milk yield of Ankole cows grazed on natural range pastures in Uganda
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: S Okello EN Sabiiti HJ SchwartzEffects of seasonal rainfall (RF) and maximum temperature (Tm) variations on milk yield of Ankole cows grazed solely on range pastures were investigated. The resulting changes in herbage growth (HG), herbage yields (HY), herbage crude protein (CPh) and neutral detergent... -
Factors affecting in sacco dietary degradation by Ankole cattle grazing natural range pastures in Uganda
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: S Okello EN Sabiiti HJ SchwartzThe in sacco disappearance of dietary dry matter after 48h of incubation in the rumen (DMd) was examined for its relationship with seasonal changes in neutral detergent fibre (NDFd), crude protein (CPd), cellulose (CELL), hemicellulose (HCELL), acid detergent lignin (ADLd)... -
The logistic model-generated carrying capacities, maximum sustained off-take rates and optimal stocking rates for Kenya's commercial ranches
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: JT Njoka PID KinyuaThis paper deals with the derivation of logistic models for cattle, sheep and goats in a commercial ranching system in Machakos District, Kenya, a savannah ecosystem with average annual rainfall of 589.3 ± 159.3mm and an area of 10 117ha... -
The influence of stocking rate, range condition and rainfall on residual herbage mass in the semiarid savanna of KwaZulu/Natal
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: G.P. Hatch --- Department of Grassland Science, Republic of South Africa N.M. Tainton --- Department of Grassland Science, Republic of South AfricaGrazing trials at two sites in the semiarid savanna of KwaZulu‐Natal were stocked with cattle at light (0.17 LSU ha‐1), intermediate (0.23 LSU ha‐1) and heavy (0.30 LSU ha‐1) stocking. Pasture disc meter data collected over 116 three‐week periods were... -
The bioeconomic implications of various drought management strategies for a communal cattle herd in the semi‐arid savanna of KwaZuIu‐Natal
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: G.P. Hatch --- Department of Range and Forage Resources, Republic of South Africa D.M. Stafford Smith --- National Rangelands Program, AustraliaThe widespread drought of the early 1990s resulted in considerable stock losses in the semi‐arid savanna of KwaZulu‐Natal. We compared the influence of four drought response strategies on herd number, milk yield, cost and net present value for a communal... -
Savanna browse production. 2: Prediction
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Caryn A Penderis --- School of Life Sciences, South Africa Kevin P Kirkman --- Grassland Science, South AfricaBrowsing herbivores are generally highly selective feeders, selecting for new shoots and young plant material. Determinations of browser carrying capacity are then greatly inflated when based on available browse biomass estimates. Our study was initiated with the aim of modelling... -
Application of the 3-PG model to a Eucalyptus grandis stand subjected to varying levels of water and nutritional constraints in KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: J. M. Campion L.J. Esprey M.C. ScholesThe 3-PG model has shown considerable potential as a tool for predicting forest productivity. As part of a model validation exercise, 3-PG was applied to an irrigated and fertilised Eucalyptus grandis stand in the KwaZulu-Natal Midlands. Simulations were run over... -
Growth modelling of Pinus roxburghii in South Africa
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: E.R. Falkenhagen --- , South AfricaThe growth in diameter at breast height, height and tree volume and plot density were studied in an unreplicated spacing trial of Pinus roxburghii at Weza, South Africa. -
Towards an Information System for Forestry
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: Christoph Kätsch --- Department of Forest Science, BrianV. Bredenkamp --- Department of Forest Science,Management of information as a production factor is imperative in modern forestry practice. However, development of individual application programmes has resulted in systems which cannot be integrated without excessive effort and expense. It is shown that the route to an... -
Optimising Nursery Operation Schedules with Multiperiod Linear Programming
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: RudolfJanse van Rensburg --- Department of Forest Science, South Africa BrianV. Bredenkamp --- Department of Forest Science, South AfricaA dynamic multiperiod linear programming model which addresses nursery scheduling is presented. Due to its dynamic nature, it provides a means to manage risks and uncertainties such as disease, rootstrike, germination and fluctuating demands. By optimising the whole production process,... -
A Site-growth Study of Eucalyptus grandis in the Mpumalanga Escarpment Area
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: J.H. Louw --- ,A site-growth study was conducted on Eucalyptus grandis on the granitic soils of the Mpumalanga escarpment area. The objectives were twofold, namely to identify those site factors that can be related to the growth of the species, as well as... -
A review of site-growth studies in South Africa
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: J.H. Louw --- ,The intensive nature of the South African forest industry requires reliable decision support systems to enhance site-specific silviculture. Furthermore, the principle of ecologically sustainable forest management requires a profound improvement in the understanding of the factors controlling tree growth and... -
Addressing Urgent Community Mental Health Needs in Rwanda: Culturally Sensitive Training Interventions
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Lisa Lopez Levers --- Duquesne University, USA Desire Kamanzi --- Kigali Health Institute, Rwanda Donatilla Mukamana --- Kigali Health Institute, Rwanda Kirrily Pells --- Institute of Commonwealth Studies, University of London, Dan-Bush Bhusumane --- Duquesne University and University of Botswana,Rwandan leaders in the health and educational sectors have begun to discuss the necessity for establishing culturally appropriate community-based mental health counselling services in Rwanda, especially trauma counselling. The need for a community psychology approach is anchored in the lingering... -
The Relationship Between Hope And Goal Achievement
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: David J.F. Maree --- University of Pretoria, Marinda Maree --- University of Pretoria, Charmaine Collins --- University of Pretoria,The aim of this study was to explore the psychological resource structure of students as assessed by the Hope Orientation Measure or HOME instrument. The aim was also to find what the relationship between this resource structure and goal achievement... -
Constructing a South African Hope Measure
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: David J. F. Maree --- University of Pretoria, Marinda Maree --- University of Pretoria, Charmaine Collins --- University of Pretoria,An instrument to assess levels of hope was developed. From a qualitative analysis of what students regarded as hope, items were constructed and a questionnaire was applied to 474 undergraduate social sciences students. The results were calibrated across gender and... -
A Psychological Support for Peacekeeping Soldiers and their Families: A Preliminary Model
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Donovan J. Kalamdien --- Stellenbosch University, Gideon A.J. Van Dyk --- Stellenbosch University,Being a military family can be challenging, and the demands placed on soldiers and their families can become very complex. Military deployments are part of a soldier's military career that cannot be avoided and have the potential to influence military... -
A Meta-Theoretical Framework for Counselling People of African Ancestry: An Ecologically Oriented Response to the Special Section Articles
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Lisa Lopez Levers --- Duquesne University, USAThis article is a review of the preceding six articles included in the Special Section related to the subject of counselling people of African ancestry. The major objective was to ascertain whether any recurring themes might be identified, and whether... -
Exploring the Role of Spirituality in the Context of the Five Factor Model of Personality in a South African Sample
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Sumaya Laher --- University of the Witwatersrand, South Africa Gregg Quy --- University of the Witwatersrand, South AfricaThe study explored the relationship between the Five Factor Model of personality and spirituality by using the NEO PI-R (Costa & McCrae, 1992) and the Spiritual Transcendence Scale (STS) (Piedmont, 1999) respectively. Participants were 94 psychology undergraduate students at a... -
Management of Post-Traumatic Stress Disorder in the Military: An Intervention Model
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Thamsanqua J. Dhladhla --- Stellenbosch University, South Africa Gideon A. J. van Dyk --- Stellenbosch University, South AfricaMilitary Forces are involved in combat, peacekeeping operations and disaster management. The nature of such operations include violent conflict, death of women and children, child soldiers and own forces. These traumatic circumstances can contribute to the development of post traumatic... -
Combining Leadership Theory with a Psychodynamic Perspective to Explain the Functioning of a Management Team
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: René van Eeden --- University of South Africa,This article illustrates how the processes and dynamics in a management team at a South African organization reflect the leadership and personality profiles of the members of the team. Participants were the 12-member management team (including the general manager). The... -
Resilience in Families Adapting to Autism Spectrum Disorder
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Leché Kapp --- Nelson Mandela Metropolitan University, Ottilia Brown --- Nelson Mandela Metropolitan University,This study explored adjustment and adaptation in families living with Autism Spectrum Disorder (ASD). Data on family resilience were collected from 19 biological mothers of children with ADS. The data were analysed qualitatively and quantitatively to yield information on factors... -
Beyond the Individual: Promoting Mental and Behavioural Health in Low- and Middle-income Countries
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Inge Petersen --- University of KwaZulu-Natal, South Africa Arvin Bhana --- Human Sciences Research Council, South Africa Kaymarlin Govender --- University of KwaZulu-Natal, South AfricaThis brief report describes a programmatic approach to health promotion that can help address the social determinants of mental-health and associated risky behaviours. Using a South African case example, we illustrate that while micro-system interventions help to strengthen individual resilience... -
Positive Side of the Work-Family Interface: A Theoretical Review
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Marissa De Klerk --- North-West University, South Africa Jan Alewyn Nel --- North-West University, South Africa Eileen Koekemoer --- North-West University, South AfricaThis narrative review considers the positive side of the work-family interface. It surveyed a range of relevant literature (1960–2012) using search terms on the positive work-family interface. From the literature it is evident that various concepts (e.g., work-family enhancement, work-family... -
Breast Cancer Health Beliefs and Perceived Barriers to Self-Examination Amongst Hindu Women in South Africa
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Catherine Govender --- University of South Africa, Prashilla Soma --- University of Pretoria, Leeana Persad --- University of Witwatersrand, Julie Moodley --- National Health Laboratory Services, Vinay Rajah --- , South AfricaThis study explored the breast cancer health beliefs and perceived barriers to breast self-examination of South African Hindu women. Participants were 68 Hindu women (mean age = 39.36 years SD=13.42) from two South African cities. They completed the Champion's Health... -
A Model for Psychosocial Well-Being of Families in a South African Context
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Vicki Koen --- North-West University, South Africa Chrizanne van Eeden --- North-West University, South Africa Sebastiaan Rothmann --- North-West University, South AfricaThis study applied the approach of Dickoff, James, and Wiedenbach (1968) to construct a conceptual framework and a model for the psychosocial well-being of families from diverse cultures in a South African context. Findings from previous qualitative research served as... -
Burnout and Work Engagement for Different Age Groups: Examining Group-Level Differences and Predictors
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Lize-Mari Haley --- North-West University, South Africa Karina Mostert --- North-West University, South Africa Crizelle Els --- North-West University, South AfricaThis study examined age-related differences of burnout and engagement levels among employees in the South African financial sector, including influences of perceived job characteristics and personal sense of coherence. Data on burnout and work engagement, job characteristics and sense of... -
Measurement Equivalence of the South African Psychological Ownership Questionnaire for Diverse South African Cultural Groups
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Chantal Olckers --- University of Pretoria, Pieter Schaap --- University of Pretoria,This study determined the measurement equivalence of the South African Psychological Ownership Questionnaire (SAPOS) for black and white South African employees. Participants were a non-probability sample of 645 professional level employees from both the private and the public sector (59.4%... -
Boman's theorem: Strengthened and applied
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: H. L. Bentley Paul CherenackA 1-variable calculus type argument is used to show that, for a function f : R 2 → R, if for all (a, b) ∈ R 2 we have that f o c is smooth for every smooth curve c... -
The Whitehead Square of the 6-point 2-sphere
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: K.A. Hardie P.J. WitbooiWe describe a model of the Whitehead square [ι 2, ι 2] ∈ π3(S 2) in the form of an order-preserving map from a 56-point model of S 3 into the minimal model of S 2 in the category of... -
On Russell and Anti Russell-Cardinals
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Horst Herrlich --- , Germany Kyriakos Keremedis --- Department of Mathematics, Greece Eleftherios Tachtsis --- Department of Statistics and Actuarial-Financial Mathematics, GreeceIn the absence of the Axiom of Choice we study countable families of 2-element sets with no choice functions which either have infinite subfamilies with a choice function or no infinite subfamilies with a choice function. -
Community impact of HIV status disclosure through an integrated community home-based care programme
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Busisiwe Ncama Leana UysThe integration of HIV-prevention activities into care has received little attention within or outside formal healthcare settings. The contribution of community home-based care services in facilitating disclosure of HIV status and reducing stigma have also not been described. This study... -
Youth's perceptions of HIV infection risk: a sex-specific test of two risk models
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Yetunde ShoboThe study examines the associations between the cumulative and additive risk models and Nigerian youth's likelihood of perceiving vulnerability to HIV infection. Both models of risk seem to provide unique contributions to such understanding. The analysis is based on data... -
The influence of peers and other significant persons on sexuality and condom-use among young adults in northern Tanzania
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Bernard Njau Sabina Mtweve Longin Barongo Rachel Manongi Juliet Chugulu Marcelina Msuya Stella Mwampeta Bertha Kiwale Joseph Lekule Hector JalipaSexual behaviour change remains a primary goal of HIV prevention efforts globally. It is a complex issue influenced by numerous unpredictable variables such as individual desires, social and cultural relationships, and environmental and economic dynamics. This study in northern Tanzania... -
Modelling the relationship between antiretroviral treatment and HIV prevention: limitations of the Spectrum AIDS Impact Model in a changing policy environment
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Nicoli NattrassThis paper shows how two publicly available epidemiological modelling packages, namely the Spectrum AIDS Impact Model and the ASSA2003 AIDS and Demographic Model, predict very different impacts from rolling out highly active antiretroviral treatment (HAART) on new HIV infections. Using... -
Epidemiological and demographic HIV/AIDS projections: South Africa
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: ThomasM. Rehle --- , USA Olive Shisana --- , South AfricaThe Epidemic Projection Package (EPP) recently developed by the UNAIDS Reference Group on Estimates, Models and Projections and the Spectrum model program developed by the Futures Group were used to model the South African HIV epidemic, project future trends in... -
Trend analysis and short-term forecast of incident HIV infection in Ghana
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Patrick Aboagye-Sarfo --- School of Engineering, Australia James Cross --- School of Engineering, Australia Ute Mueller --- School of Engineering, AustraliaThe study uses time-series modelling to determine and predict trends in incident HIV infection in Ghana among specific age groups. The HIV data for Ghana were grouped according to northern and southern spatial sectors as they exhibited slightly different data... -
The effects of gender and socioeconomic status on youth sexual-risknorms: evidence from a poor urban community in South Africa
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Michael Rogan --- Health Economics and HIV/AIDS Research Division (HEARD), South Africa Michaela Hynie --- Department of Psychology, Canada Marisa Casale --- Health Economics and HIV/AIDS Research Division (HEARD), South Africa Stephanie Nixon --- Department of Physical Therapy, Canada Sarah Flicker --- Faculty of Environment Studies, Canada Geoff Jobson --- Health Economics and HIV/AIDS Research Division (HEARD), South Africa Suraya Dawad --- Health Economics and HIV/AIDS Research Division (HEARD), South AfricaHIV and AIDS remains one of the most serious problems facing youths in many sub-Saharan African countries. Among young people in South Africa, gender is linked with a number of HIV-risk behaviours and outcomes. The literature suggests that factors such... -
Understanding HIV-related posttraumatic stress disorder in South Africa: a review and conceptual framework
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Charles Young --- Department of Psychology, South AfricaA number of epidemiological studies have attempted to measure the prevalence of HIV-related posttraumatic stress disorder (PTSD) in sub-Saharan Africa. A systematic review of the literature identified eight relevant studies that put current estimates of the prevalence of HIV-related PTSD... -
Risk management in HIV/AIDS: ethical and economic issues associated with restricting HAART access only to adherent patients
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Richard Chawana --- , South Africa Donna Knapp van Bogaert --- , South AfricaLike many other developing nations, South Africa faces the challenge of mobilising resources in response to the HIV pandemic. There is a large budget gap between the ideal and the actual amount of funding needed to achieve universal access to... -
Factors associated with HIV infection among sexually experienced adolescents in Africa: a pooled data analysis
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Stella Babalola --- Johns Hopkins Bloomberg School of Public Health, United StatesThe article examines the factors associated with HIV status among adolescents aged 15–19 years in 13 African countries: Côte d'Ivoire, Democratic Republic of Congo, Guinea, Kenya, Liberia, Mali, Malawi, Rwanda, Sierra Leone, Swaziland, Tanzania, Zambia and Zimbabwe. The data were... -
Fear appeals in HIV-prevention messages: young people's perceptions in northern Tanzania
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Sheri Bastien --- Faculty of Medicine, Institute for Basic Medical Sciences, NorwayThe aims of the study were to elicit the perceptions of young people in Tanzania on the role of fear appeals in HIV-prevention messages and to identify important contextual factors that may influence young people's perceptions of HIV-prevention posters. A... -
A framework to expand public services to children with biomedical healthcare needs related to HIV in the Free State, South Africa
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Marianne Reid --- , South Africa Yvonne Botma --- Faculty of Health Sciences, School of Nursing, South AfricaThe study undertook the development of a framework for expanding the public services available to children with biomedical healthcare needs related to HIV in South Africa. The study consisted of various component projects which were depicted as phases. The first... -
Challenges and coping strategies of orphaned children in Tanzania who are not adequately cared for by adults
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Marguerite Daniel --- Department of Health Promotion and Development, Norway Angela Mathias --- Department of Health Promotion and Development, NorwayOrphaned children in poor rural communities sometimes have no adult who is able to care for them or else the adult caregiver is not able to provide adequate care. Tanzania remains one of the poorest countries in the world, and... -
Acceptability of routine HIV counselling and testing among a sample of South African students: Testing the Health Belief Model
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Jani Nöthling --- Department of Psychiatry, South Africa Ashraf Kagee --- Department of Psychology, South AfricaRoutine HIV counseling and testing (RCT) is a necessary first step in accessing health care for persons who may test HIV-positive. Despite the availability of RCT in many South African settings, uptake has often been low. We sought to determine... -
The IFR process: beyond the specialist workshop
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: D Louw D Hughes A BirkheadThe process of determining Instream Flow Requirements (IFRs) has been well developed to the point at which an IFR table which quantifies the temporal distribution of discharge, upon which the modified flow regime is based, is produced. During the last... -
Phosphorus sorption characteristics of sediment in the Simiyu and Kagera River basins: implications for phosphorus loading into Lake Victoria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RA TamatamahAs part of a larger study to assess the influence of land use on riverine and atmospheric phosphorus (P) loading to Lake Victoria, P sorption characteristics of eight composite bottom sediment samples from the Simiyu and Kagera rivers were determined... -
Oualidia lagoon, Morocco: an estuary without a river
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: K Hilmi VG Koutitonsky A Orbi JI Lakhdar M ChagdaliThis study describes some physical oceanography features of an estuary maintained by fresh groundwater inflow. The mesoscale variability of currents, temperature and salinity are documented from moored current meter observations of 12 days duration at three stations. Current speeds exceeded... -
Growth, reproduction and population structure of Diplotaxodon limnothrissa in the southeast arm of Lake Malawi
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: GeoffreyZ Kanyerere OlafLF Weyl AnthonyJ BoothDiplotaxodon limnothrissa is a widely distributed species occurring throughout Lake Malawi from the surface to a depth of at least 220m. It is probably the most abundant cichlid in the lake, with biomass estimates of around 87 000t in the... -
Modelling highly variable daily maximum water temperatures in a perennial South African river system
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NicholasA Rivers-Moore CarelN Bezuidenhout GrahamPW JewittThirty-three months of observed hourly water temperatures were used to calculate daily maximum water temperatures for nine sites within the Sabie-Sand River system, Mpumalanga Province, South Africa. A suite of statistical models for simulating daily maximum water temperatures, of differing... -
Predictor variables for moggel (Labeo umbratus) biomass and production in small South African reservoirs
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: WM Potts AJ Booth T Hecht TG AndrewThe biomass and production of moggel, Labeo umbratus, in five small previously unexploited Eastern Cape reservoirs were estimated and related to environmental conditions. Biomass and production estimates varied widely between the reservoirs. Whilst the production/biomass ratio was not a good... -
Developing a site selection tool to assist reintroduction efforts for the Southern Ground-Hornbill Bucorvus leadbeateri
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Dirk Cilliers --- Unit for Environmental Sciences and Management, Potchefstroom Campus, South Africa Steven Evans --- Unit for Environmental Sciences and Management, Potchefstroom Campus, South Africa Hendri Coetzee --- Unit for Environmental Sciences and Management, Potchefstroom Campus, South Africa Leon van Rensburg --- Unit for Environmental Sciences and Management, Potchefstroom Campus, South AfricaThe Southern Ground-Hornbill Bucorvus leadbeateri (SGH) is regarded as Vulnerable globally and Endangered in South Africa as a result of losing close to 70% of its range and 50% of its historic population in the country. One of the conservation... -
Breeding phenology and moult of the endemic Bannerman's Weaver Ploceus bannermani
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Yahkat Barshep --- AP Leventis Ornithological Research Institute, Nigeria Shiiwua A Manu --- AP Leventis Ornithological Research Institute, NigeriaThe breeding phenology and moult cycle of the vulnerable and range-restricted Bannerman's Weaver Ploceus bannermani was studied on the Obudu Plateau in the eastern region of Nigeria. The peak breeding season was between August and October; a major cause of... -
An Integrated System for Forest Management and Silvicultural Planning and Control in South African State Forestry
Item type: Journal Article • Journal: South African Forestry Journal • Authors: H.W. Kassier --- Forest Management Division, Department of Water Affairs, Forestry and Environmental Conservation,A computerised plantation analysis system (COMPAS) for commercial plantation management, planning and control is described and illustrated. Present uses in South African State forestry and future development of the system are discussed. -
Predicting Growth of Eucalyptus grandis: A Worked Example
Item type: Journal Article • Journal: South African Forestry Journal • Authors: B.V. Bredenkamp --- Natal Forestry Research Centre,A worked example demonstrates the simulation of growth patterns in unthinned stands of Eucalyptus grandis. It is shown how response to thinning can be deduced and projections of diameter and height growth can be made for sites differing in growth... -
Studies of Growth and Stand Structure in Plantations of Pinus patula
Item type: Journal Article • Journal: South African Forestry Journal • Authors: Y. de Villiers --- , A. van Laar --- Faculty of Forestry,Mensurational data collected for management inventories were used to obtain estimates for the parameters of equations with age, and in other cases with age, stand density and site index as predictor-variables, growth and stand structure characteristics as dependent variables. The... -
An Introduction to Digital Terrain Modelling in Forest Site Analysis—An Example from the Grabouw-Lebanon Key Area
Item type: Journal Article • Journal: South African Forestry Journal • Authors: R.N. Thwaites --- Saasveld Forestry Research Centre,An outline of the concept of digital terrain modelling (DTM) is provided which includes the model structure, data capture methods and approaches to analysis and display. Mention is made of the variety of work environments in which DTM is used... -
Curing Rates in the Grass Sward of the Highland Sourveld in the Natal Drakensberg
Item type: Journal Article • Journal: South African Forestry Journal • Authors: TheresaM. Everson --- , C.S. Everson --- , H.M. Dicks --- , A.G. Poulter --- ,Data on the curing rates of one, two and three-year-old grassland are presented. Curing is initiated at the end of April and progresses rapidly up to the middle of May. By June the grasses are 95 % cured, increasing the... -
THE USE OF MICROCOMPUTERS IN WATER RESOURCE MODELLING
Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: W. J.R. Alexander --- Department of Civil Engineering,Microcomputers are the ideal tool for water resource modelling. Not only are they fast and computationally efficient, but they can also provide the user with dynamic graphical displays which greatly assist in the interpretation of the results of the analyses... -
MODELS OF ECOSYSTEMS AND AQUATIC ENVIRONMENTS: DEVELOPMENT AND APPLICATION
Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: B.R. Allanson --- , South AfricaAn historical treatment of a number of principal events is given. This leads to an assessment of the current research approach in hydrobiology and its success in the development of process orientated ecosystem component models. With the contemporaneous development of... -
A RULE-BASED ECOSYSTEM MODEL FOR THE MANAGEMENT OF LAKE ST LUCIA
Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: R.H. Taylor --- , South Africa B.P. Farm --- Dept. of Ecology and Behavioural Biology, United States of America A.M. Starfield --- Dept. of Ecology and Behavioural Biology, United States of AmericaLand transformations in the catchments of Lake St Lucia have altered the hydrology of the system and increased management is now needed to counteract these changes. There are several management options available, but prior to implementing them we must be... -
APPLICATION OF LAVSOE, AN EUTROPHICATION MODEL, TO BLOEMHOF DAM
Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: J.N. Rossouw --- ,In 1985 the Department of Water Affairs introduced an effluent phosphate standard of 1 mg l−1 (as P) in seven potentially sensitive catchments. Although this is an uniform standard, permits can be granted for effluents to exceed the standard in... -
WATER QUALITY MODELLING PERCEPTIONS OF A WATER RESOURCE MANAGEMENT ORGANIZATION
Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: H.D. Furness --- Scientific Services Division, South Africa W.N. Richards --- Scientific Services Division, South AfricaThe use of models by the South African water industry is discussed. It is suggested that climatic conditions and existing legislation have influenced the formulation of models. Future model requirements by the water Industry are outlined. Changes are suggested which... -
FUTURE CHALLENGES IN WATER QUALITY MODELLING WITH PARTICULAR REFERENCE TO OPERATIONALLY CLOSED CATCHMENTS
Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: S.F. Forster --- Department of Water Affairs, South Africa F.A. Stoffberg --- Department of Water Affairs, South Africa J.A. van Rooyen --- Department of Water Affairs, South AfricaAs a result of the declining quality of many water sources, the use of water quality models in planning is increasing. To date applications have involved the simulation of total dissolved salts and nutrients, largely in catchments affected by urban... -
Drift Patterns of Anchovy Engraulis Capensis Larvae in The Southern Benguela, and Their Possible Importance for Recruitment
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M. D. Skogen L. J. Shannon J. E. StiansenIn the southern Benguela, successful recruitment of Cape anchovy Engraulis capensis is highly variable and seems to be dependent on the spawning biomass only to a small extent. This paper investigates how the variations in the drift patterns of larvae... -
A Statistical Model for Stock Assessment of Southern Bluefin Tuna with Temporal Changes in Selectivity
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: D. S. Butterworth J. N. Ianelli R. HilbornAssessment of the status of southern bluefin tuna (SBT) by Australia and Japan has used a method (ADAPT) that imposes a number of structural restrictions, and is similar to methods used for a number of stocks world-wide. A flexible method... -
Ecosystem approach to fisheries management in the southern Benguela: a workshop overview
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L. J. Shannon K. L. Cochrane C. L. Moloney P. FréonA workshop was held in Cape Town in December 2002 to introduce the concept of an ecosystem approach to fisheries (EAF) management in the southern Benguela, and to examine the options for implementing an EAF in South Africa. The workshop... -
A brief introduction to some approaches to multispecies/ecosystem modelling in the context of their possible application in the management of South African fisheries
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: D. S. Butterworth É. E. PlagányiAspects of the potential application of multispecies/ecosystem modelling to advise the management of South African fisheries are discussed. In general, reliable predictive ability from such models is likely to be achieved sooner for top predators, because relatively fewer links need... -
An ecosystem framework for fisheries management in the southern Benguela upwelling system
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L. J. Shannon C. L. MoloneyA "four-step framework" for applying ecosystem approaches to fisheries management in the southern Benguela is proposed. First, static ecosystem models can be used to highlight important interactions by assessing the net trophic impacts of each species on all the others... -
Ecosystem approach to fisheries management in the northern Benguela: the Namibian experience
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J-P. Roux L. J. ShannonThe northern Benguela marine resources have a long history of questionable management primarily because of the limitations of management measures under the political framework of the time (either free access or under an international authority with no national representation, authority... -
Simulations of fishing effects on the southern Benguela fish community using an individual-based model: learning from a comparison with ECOSIM
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: Y-J. Shin L. J. Shannon P. M. CuryBy applying an individual-based model (OSMOSE) to the southern Benguela ecosystem, a multispecies analysis is proposed, complementary to that provided by the application of ECOPATH/ECOSIM models. To reconstruct marine foodwebs, OSMOSE is based on the hypothesis that predation is a... -
Modelling stock dynamics in the southern Benguela ecosystem for the period 1978–2002
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L. J. Shannon V. Christensen C. J. WaltersAn ecosystem model of the southern Benguela was fitted to available time-series data for the period 1978–2002, to explore how changes in target fish populations in this ecosystem can be attributed to feeding interaction terms and population control patterns, the... -
Lessons learnt from a comparison of three ecosystem models for Port Phillip Bay, Australia
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: E. A. Fulton A. D. M. SmithComparing multiple models applied to the same system can be highly instructive, both with regard to the system of interest and the models. In this case, three ecosystem simulation models (ECOSIM, Bay Model 2 [BM2] and the Integrated Generic Bay... -
Consideration of multispecies interactions in the Antarctic: a preliminary model of the minke whale – blue whale – krill interaction
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M. Mori D. S. ButterworthAs a first step in investigating the major predator–prey interactions in the Antarctic, a model describing blue whales Balaenoptera musculus, minke whales Balaenoptera acutorostrata and krill Euphausia superba is developed. Blue and minke whales feed mainly on krill, and they... -
Age structure or functional response? Reconciling the energetics of surplus production between single-species models and ECOSIM
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: K. Y. AydinWhole-ecosystem foodweb models, specifically the dynamic model ECOSIM, contain specific hypotheses for surplus production that differ from traditional single-species management models. Specifically, ECOSIM begins with an assumption that all species are tightly connected and energetic surplus does not arise through... -
Towards the development of an environmental rule-based model for predicting recruitment in Brazilian sardine Sardinella brasiliensis
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Jablonski LFL LegeyA rule-based model was built in order to analyse the effects of environmental variables (wind stress, Ekman transport, turbulence, and sea surface temperature [SST]) on the recruitment of the Brazilian sardine Sardinella brasiliensis. The purpose of modelling was (1) to... -
Below the Kolmogorov scale: the non-turbulent sex life of phytoplankton
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L PeperzakBelow the Kolmogorov length scale there is no turbulence and phytoplankton gametes swim in order to encounter each other and achieve syngamy. An encounter rate model, Z = π √2 R2 u N, is derived incorporating cell size (R), swimming... -
Modelling the influence of silicon and phosphorus limitation on the growth and toxicity of Pseudo-nitzschia seriata
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: K Davidson J FehlingPseudo-nitzschia seriata (Cleve) H. Peragallo isolated from Scottish west coast waters was studied in laboratory batch culture. The neurotoxin domoic acid was produced in both P- and Si-limited stationary phase, but in greater quantities when Si was the limiting nutrient... -
The use of fuzzy logic for data analysis and modelling of European harmful algal blooms: results of the HABES project
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AN Blauw P Anderson M Estrada M Johansen J Laanemets L Peperzak D Purdie R Raine E VahteraFuzzy logic was applied to model blooms of Nodularia spumigena, Dinophysis spp., Alexandrium minutum, Karenia mikimotoi and Phaeocystis globosa at various European sites as part of the Harmful Algal Blooms Expert System (HABES) project. This modelling approach was useful in... -
First Lagrangian ROMS–IBM simulations indicate large losses of chokka squid Loligo reynaudii paralarvae from South Africa's Agulhas Bank
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MJ Roberts --- Department of Environmental Affairs, South Africa C Mullon --- , FrancePresent knowledge of ocean currents based on in situ observation and models suggests that passive biological material such as eggs and larvae can be advected offshore away from the Agulhas Bank, South Africa, and hence removed from the ecosystem on... -
A spatial- and age-structured assessment model to estimate the impact of illegal fishing and ecosystem change on the South African abalone Haliotis midae resource
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: ÉE Plagányi --- Department of Mathematics and Applied Mathematics, South Africa DS Butterworth --- Department of Mathematics and Applied Mathematics, South AfricaThe management of abalone stocks worldwide is complicated by factors such as illegal fishing combined with the difficulties of assessing a sedentary (but not immobile) resource that is often patchily distributed. The South African abalone Haliotis midae fishery is faced... -
Modelling regime shifts in the southern Benguela: a frame-based approach
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MD Smith --- Marine Research (MA-RE) Institute and Zoology Department, South Africa A Jarre --- Marine Research (MA-RE) Institute and Zoology Department, South AfricaThis study explores the usefulness of a frame-based modelling approach in the southern Benguela upwelling ecosystem, with four frames describing observed small pelagic fish dominance patterns. We modelled the dynamics of sardine Sardinops sagax and anchovy Engraulis encrasicolus populations under... -
An alternative method for estimating the status of resident reef fish stocks, based on differential fishing effort across a marine reserve boundary
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Götz --- Elwandle Node, South Africa SE Kerwath --- Branch Fisheries, Department of Agriculture, South Africa CG Attwood --- Marine Research Institute, Zoology Department, South Africa WHH Sauer --- Department of Ichthyology and Fisheries Science, South AfricaThe stock status of roman Chrysoblephus laticeps was estimated in the Goukamma, a temperate South African marine protected area (MPA). Standardised catch per unit effort (CPUE) from a controlled angling survey on both sides of the MPA border was employed... -
Movement patterns of coastal bottlenose dolphins in the presence of a fast-flowing, prevailing current: shore-based observations at Cape Vidal, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Photopoulou --- Sea Mammal Research Unit, UK PB Best --- , South Africa PS Hammond --- Sea Mammal Research Unit, UK KP Findlay --- Department of Oceanography, University of Cape Town, South AfricaThe presence and movement of Indo-Pacific bottlenose dolphins Tursiops aduncus were investigated using shore-based observations made during a humpback whale Megaptera novaeangliae migration survey at Cape Vidal, South Africa, undertaken between June and October 1988–1991. Occurrence was analysed as counts... -
Acoustic behaviour of southern right whales in relation to numbers of whales present in Walker Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: LH Hofmeyr-Juritz --- , South Africa PB BestEstimating numbers of whales present in an area from recorded call rates could be a useful conservation tool. We recorded southern right whale Eubalaena australis vocalisations and presence in Walker Bay on the south coast of South Africa. In all,... -
Seasonal fluctuations in occurrence of inshore Bryde's whales in Plettenberg Bay, South Africa, with notes on feeding and multispecies associations
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: GS Penry --- , UK VG Cockcroft --- Department of Zoology, Nelson Mandela Metropolitan University, South Africa PS Hammond --- , UKSeasonal fluctuations in the occurrence of inshore South African Bryde's whales Balaenoptera edeni were investigated between November 2005 and June 2008. Sighting data were collected in Plettenberg Bay on the south-east coast of South Africa. Bryde's whale occurrence was modelled... -
Modelling the effect of food availability on recruitment success of Cape anchovy ichthyoplankton in the southern Benguela upwelling system
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: V Koné --- Département d'Environnement, Côte d'Ivoire C Lett --- , France P Fréon --- , FranceCape anchovy Engraulis encrasicolus adapted its reproductive strategies to the southern Benguela system by spawning over the Agulhas Bank, an area of low productivity that is located upstream of the predominant upwelling system. Frontal jet currents transport eggs and larvae... -
Assessing stocks in data-poor African fisheries: a case study on the white grouper Epinephelus aeneus of Mauritania
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: B Meissa --- , Mauritanie D Gascuel --- , France E Rivot --- , FranceThe lack of reliable stock assessment for numerous exploited stocks in West Africa often results from poor-quality data, high multi-specificity of captures, and the heterogeneity of exploitation methods. However, many signs of overexploitation exist, particularly for demersal resources, highlighting the... -
White sharks Carcharodon carcharias at Bird Island, Algoa Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: ML Dicken --- Department of Ichthyology and Fisheries Science, South Africa MJ Smale --- , South Africa AJ Booth --- Department of Ichthyology and Fisheries Science, South AfricaWe present the first quantitative study of the occurrence, size and sex of white sharks Carcharodon carcharias at Bird Island, Algoa Bay. Twenty-two boat trips were made to Bird Island between November 2009 and October 2011 to chum for sharks... -
Stock-environment recruitment analysis for Namibian Cape hake Merluccius capensis
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: P Kainge --- National Marine Information and Research Centre, Namibia N Bahamon --- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Spain CH Bartholomae --- National Marine Information and Research Centre, Namibia JN Kathena --- National Marine Information and Research Centre, Namibia AK van der Plas --- National Marine Information and Research Centre, Namibia A Gordoa --- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), SpainThe factors modulating recruitment success of Cape hake Merluccius capensis in Namibian waters are still unresolved. In this study, we used generalised additive models, regression tree analysis and the conventional Ricker model to examine the effect of environmental indices and... -
Patterns in abundance, population structure and biology of knife prawn Haliporoides triarthrus on deep-water trawl grounds off eastern South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J Robey --- Oceanographic Research Institute, South Africa ST Fennessy --- Oceanographic Research Institute, South Africa BI Everett --- Oceanographic Research Institute, South Africa J Santos --- Norwegian College of Fisheries Science, Norway JC Groeneveld --- Oceanographic Research Institute, South AfricaThe deep-water trawl fishery along the KwaZulu-Natal coast of South Africa targets several crustacean species, with the knife (or pink) prawn Haliporoides triarthrus contributing most of the catch. Logbook data of fishing effort and catch between 1988 and 2010 were... -
An end-to-end coupled model ROMS-N2P2Z2D2-OSMOSE of the southern Benguela foodweb: parameterisation, calibration and pattern-oriented validation
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Travers-Trolet --- IFREMER [French Research Institute for the Exploitation of the Sea], France Y-J Shin --- IRD [Research Institute for Development] CRH [Centre of Mediterranean and Tropical Fisheries Research], France JG Field --- Marine Research Institute, South AfricaIn order to better understand ecosystem functioning under simultaneous pressures (e.g. both climate change and fishing pressures), integrated modelling approaches are advocated. We developed an end-to-end model of the southern Benguela ecosystem by coupling the high trophic level model OSMOSE... -
A bootstrap method for estimating bias and variance in statistical fisheries modelling frameworks using highly disparate datasets
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: BÞ Elvarsson --- Science Institute, Iceland L Taylor --- Science Institute, Iceland VM Trenkel --- Ifremer [French Research Institute for the Exploitation of the Sea], France V Kupca --- HPC2N [High Performance Computing Center North], Umeå University, Sweden G Stefansson --- Science Institute, IcelandStatistical models of marine ecosystems use a variety of data sources to estimate parameters using composite or weighted likelihood functions with associated weighting issues and questions on how to obtain variance estimates. Regardless of the method used to obtain point... -
Agriculture and Climate Change in Cameroon: An Assessment of Impacts and Adaptation Options
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Yong D. Ngondjeb --- , CameroonThis study aims to assess the economic impact of climate change on crop farming activities in the Sudano-Sahelian Area of Cameroon. The study uses the Ricardian model and is based on farm data generated from a survey carried out in... -
Competitive Positioning and the Survival of Indigenous Firms in Nigeria: The Case Study of Glomobile, Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Ayodele I. Shittu --- Dongwu Business School and Center for Enterprise Innovation and Development, PR China Jielin Dong --- Dongwu Business School and Center for Enterprise Innovation and Development, PR China Li Jing --- Dongwu Business School and Center for Enterprise Innovation and Development, PR ChinaIn this paper, we provide an exploratory view of the competitive analysis of indigenous firms in Nigeria's dynamic and competitive telecommunications industry. Adopting a case study approach, we analysed the key factors behind the survival of new entrant indigenous firms... -
Conceptual View of Mobile Business Models for Rural Consumers in India
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Kasina V. Rao --- , India Rajendra M. Sonar --- , IndiaRendering value for users through mobile services is key for mobile business models anywhere. Through mobiles, for the first time ever, many public and private services have now reached poor households and communities. The demand for mobile applications is fast... -
Adoption of Agricultural Innovations: The Case of Improved Sweet Potato in Wedza Community of Zimbabwe
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Shakespear Mudombi --- Institute for Economic Research on Innovation (IERI), Tshwane University of Technology, South AfricaThe smallholder farming sector plays an important role in agricultural production. However this sector is constrained by vulnerability to climatic variations, inadequate access to farming inputs, inappropriate technologies and limited access to markets. There have been concerted efforts by various... -
Government R&D Impact on the South African Macroeconomy
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Radhika Perrot --- Mapungubwe Institute for Strategic Reflection, South Africa (MISTRA) David Mosaka --- Beracah Consulting, South Africa Lefentse Nokaneng --- Beracah Consulting, South Africa Rita Sikhondze --- Wits Business School, Wits University, South AfricaThis article analyses the impact of government R&D on the macro-economy of South Africa. Most literature on the impact of R&D on the economy has been on advanced countries, where R&D expenditure as per cent of the GDP has been... -
Breeding strategies for forest trees: Concepts and challenges
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: T White --- School of Forest Resources and Conservation, U.S.A.This paper describes some recent developments that affect the way forest geneticists think about breeding strategies for forest trees. The topics are grouped into several categories: (1) General Concepts; (2) Breeding Population Size; (3) Breeding Population Structure; (4) Management of... -
Modelling growth and water use in four Pinus patula stands with the 3-PG model
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors:Accurate prediction ofgrowth andyield offorest plantations remains importantto the forestry industry for such purposes as assessing the benefits ofsilvicultural practices, matching species to site, understanding economic risks, predicting profitability and scheduling harvests. Conventional methodology is based on statistically-derived stand growth... -
A new approach to modelling streamflow reductions resulting from commercial afforestation in South Africa
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: M.B. Gush --- Environmentek CSIR, D.F. Scott --- Department of Earth and Environmental Sciences, Canada G.P.W. Jewitt --- School of Bio-Resources Engineering and Environmental Hydrology, R.E. Schulze --- School of Bio-Resources Engineering and Environmental Hydrology, L.A. Hallowes --- , A.H.M. Görgens --- Dept. of Civil Engineering,The Department of Water Mfairs and Forestry has, for some time, needed a comprehensive tool to incorporate the impacts of commercial afforestation on water resources into water use authorisation and allocation processes. Simulation modelling on a national scale, using the... -
Site and stand analysis for growth prediction of Eucalyptus grandis on the Zululand coastal plain
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: M. du Plessis --- , J Zwolinski --- ,The integration of site information with that of tree growth is of special importance in Zululand, where sustainable supply of timber is essential for local processing and export commitments. Site prediction growth models need to be based on easily attainable... -
The wood quality of the South African timber resource for high-value solid wood products and its role in sustainable forestry
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: F.S. Malan --- ,Maximising volume growth and yield per unit area is generally recognised as an important objective towards maintaining or enhancing forest productivity. However, the forest industry's future success will also be judged on how well it understands the qualities of the... -
Estimating the leaf area index (LAI) of black wattle from Landsat ETM+ satellite imagery
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: S.T. Ghebremicael --- School of Applied Environmental Sciences, Faculty of Science and Agriculture, South Africa C.W. Smith --- , South Africa F.B. Ahmed --- School of Applied Environmental Sciences, Faculty of Science and Agriculture, South AfricaRemote sensing techniques have the potential to provide resource managers with a rapid and economical method of acquiring information related to forest productivity and water use. This study evaluated the utility ofLandsat ETM +satellite imagery to predict canopy attributes ofBlack... -
Equations for predicting the biomass of Acacia cyclops and Acacia saligna in the western and eastern Cape regions of South Africa Part 2: Stand-level models
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: A. van Laar --- Faculty of Agricultural and Forestry Sciences, J.M. Theron --- Faculty of Agricultural and Forestry Sciences,The study deals with stand-level models for estimating wood biomass for different tree sizes and different biomass categories. It was carried out on farms and nature reserves in three regions. The stratification was identical with that in part 1 of... -
Modelling maximum canopy conductance and transpiration in Eucalyptus grandis stands not subjected to soil water deficits
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: J. M. Campion --- , Republic of South Africa P.J. Dye --- Environmentek, CSIR, c/o Agrometeorology, Republic of South Africa M.C. Scholes --- School of Animal, Plant and Environmental Sciences, Republic of South AfricaThere is much current interest in predicting the maximum amount of water that can be transpired by Eucalyptus trees. It is possible that industrial waste water may be applied as irrigation water to eucalypts and it is important to predict... -
Growth models for Pinus patula in Angola
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: C Delgado-Matas --- Faculty of Agrarian Sciences, Angola T Pukkala --- , FinlandThis study developed growth models for Pinus patula Schiede ex Schltdl. et Cham. for the Central Highlands of Angola for simulating the development of stand characteristics. The model set included dominant height, individual-tree diameter increment, individual-tree height and self-thinning models... -
The use of near-infrared scanning for the prediction of pulp yield and chemical properties of Pinus patula in the Mpumalanga escarpment area of South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: C Kipuputwa --- School of Natural Resource Management, South Africa V Grzeskowiak --- , South Africa JH Louw --- School of Natural Resource Management, South AfricaNear-infrared (NIR) scanning technology is regarded as a potential tool for rapid determination of wood properties, which can substitute time-consuming and costly traditional methods. Pinus patula is the most important softwood species in South Africa, and this study is aimed... -
Growth and yield models for Eucalyptus grandis grown in Swaziland
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: M du Plessis --- , South Africa H Kotze --- , South AfricaThe aim of this study was to develop a stand-level growth and yield model for short-rotation Eucalyptus grandis grown for pulp wood production at Piggs Peak in Swaziland. The data were derived from a Nelder 1a spacing trial established with... -
Development of site index curves for Pinus kesiya in the Philippines
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: RIC Lumbres --- Department of Forest Resources, Korea YJ Lee --- Department of Forest Resources, Korea YO Seo --- Department of Forest Resources, Korea FG Calora --- , PhilippinesThis study was conducted to develop a height–age growth model and site index curves for site quality evaluation of old secondary-growth stands of Pinus kesiya in the northern Philippines. The Chapman-Richards growth function was used in the guide curve method... -
Site quality assessment of a Pinus radiata plantation in Victoria, Australia, using LiDAR technology
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Y Chen --- School of Geography and Environmental Science, Australia X Zhu --- School of Geography and Environmental Science, AustraliaThe aim of site quality assessment of Pinus radiata plantations is to determine the quality and productivity of the growing stock at different sites. It provides a useful indication of the site productivity to assist in the allocation of optimum... -
Machine productivity and residual harvesting residues associated with a cut-to-length harvest system in southern Tasmania
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: MR Ghaffariyan --- , Australia J Sessions --- Department of Forest Engineering, Resources and Management, USA M Brown --- Office of PVC Research, AustraliaThe cut-to-length method is a preferred method for harvest of pine plantations in Australia. The cut-to-length method studied in southern Tasmania consists of a feller-buncher, processor, forwarder, grapple loader and tractortrailers that were producing only pulp logs for the plantation... -
Growth models based on radial increment observations for eight pine species in Angola
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Cristobal Delgado-Matas --- Faculty of Agrarian Sciences, Angola Timo Pukkala --- School of Forest Sciences, FinlandGrowth models for the Central Highlands of Angola were developed in this study for Pinus pseudostrobus Lindl., P. kesiya Royle ex Gordon, P. devoniana Lindl., P. chiapensis (Martinez) Andresen, P. elliottii Engelm., P. greggii Engelm. ex Parl., P. montezumae Lamb... -
Stand basal area model for Cunninghamia lanceolata (Lamb.) Hook. plantations based on a multilevel nonlinear mixed-effect model across south-eastern China
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: LiFang Zhao --- Center for Earth Observation and Digital Earth, China ChunMing Li --- Institute of Forest Resource Information Techniques, ChinaBased on a multilevel nonlinear mixed-effect model approach, a stand basal area model was developed for Cunninghamia lanceolata (Lamb.) Hook. plantations belonging to the National Forest Inventory in China. The database consists of 583 plots embracing 18 different blocks within... -
Developing allometric equations for estimating leaf area and leaf biomass of Artocarpus chaplasha in Raghunandan Hill Reserve, Bangladesh
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Swapan Kumar Sarker --- Department of Forestry and Environmental Science, Bangladesh Niamjit Das --- Department of Forestry and Environmental Science, Bangladesh Md Qumruzzaman Chowdhury --- Department of Forestry and Environmental Science, Bangladesh Md Mohasinul Haque --- Department of Forestry and Environmental Science, BangladeshEstimation of leaf area (LA) and leaf biomass (LB) is important to understand plant physiological and carbon assimilation processes, and tree growth models. The aim of this study was to develop and compare allometric equations for predicting LA and LB... -
Models for estimation of carbon sequestered by Cupressus lusitanica plantation stands at Wondo Genet, Ethiopia
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Leakemariam Berhe --- , Ethiopia Genene Assefa --- Wondo Genet College of Forestry and Natural Resources, Ethiopia Tesfay Teklay --- Wondo Genet College of Forestry and Natural Resources, EthiopiaThis study compared models for estimating carbon sequestered aboveground in Cupressus lusitanica plantation stands at Wondo Genet College of Forestry and Natural Resources, Ethiopia. Relationships of carbon storage with tree component and stand age were also investigated. Thirty trees of... -
Development and validation of stem volume models for Pinus kesiya in Benguet province, Philippines
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Roscinto IanC Lumbres --- Department of Forest Resources, Korea Young Jin Lee --- Department of Forest Resources, KoreaStem volume equations (overbark) were developed, using established volume equation forms, and validated using a subset of the data collected for Pinus kesiya in Benguet province, Philippines. A total of 481 trees from Pinus kesiya stands in Benguet were measured... -
Overhead irrigation increased winter chilling and floral bud production in Eucalyptus nitens
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Robin AW Gardner --- Institute for Commercial Forestry Research, South Africa Isa Bertling --- Horticultural Science, School of Agricultural, Earth and Environmental Sciences, South Africa Michael J Savage --- Agro-meteorology, Soil-Plant-Atmosphere Research, School of Agricultural, Earth and Environmental Sciences, South AfricaEucalyptus nitens requires a sufficiently cold winter to produce flower buds. In areas in South Africa where E. nitens commercial plantations as well as breeding and production seed orchards are located, winter chilling is often insufficient for floral bud initiation... -
Generic linear mixed-effects individual-tree biomass models for Pinus massoniana in southern China
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Liyong Fu --- Research Institute of Forest Resource Information Techniques, China Weisheng Zeng --- Academy of Forest Inventory and Planning, State Forestry Administration, China Huiru Zhang --- Research Institute of Forest Resource Information Techniques, China Guangxing Wang --- Research Center of Forestry Remote Sensing and Information Engineering, China Yuancai Lei --- Research Institute of Forest Resource Information Techniques, China Shouzheng Tang --- Research Institute of Forest Resource Information Techniques, ChinaQuantification of forest biomass is important for practical forestry and for scientific purposes. It is fundamental to develop generic individual-tree biomass models suitable for large-scale forest biomass estimation. However, compatibility of forest biomass estimates at different scales may become a... -
Higher-risk sexual behaviour among HIV patients receiving antiretroviral treatment in Ibadan, Nigeria
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: BenjaminO OlleyA stress–coping model was tested to examine the role that negative life events, coping methods, and depression might play in moderating the associations between HIV-related factors (ARV drug regimen, HIV staging and CD4 count) and higher-risk sexual behaviours of people... -
A model for understanding the relationship between stigma and healthcare-seeking behaviour among people living with HIV/AIDS in sub-Saharan Africa
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: NgoziC Mbonu --- Department of Health Promotion, The School for Public Health and Primary Care (CAPHRI), Faculty of Health, Medicine and Life Sciences, The Netherlands Bart Van den Borne --- Department of Health Promotion, The School for Public Health and Primary Care (CAPHRI), Faculty of Health, Medicine and Life Sciences, The Netherlands NanneK De Vries --- Department of Health Promotion, The School for Public Health and Primary Care (CAPHRI), Faculty of Health, Medicine and Life Sciences, The NetherlandsPeople living with HIV or AIDS (PLHIV) in sub-Saharan Africa sometimes have care-seeking behaviours that result in a suboptimal quality of life. This paper seeks to examine the role of stigma in the care-seeking behaviour of PLHIV. We hypothesise that... -
Age estimation, growth rate and size at sexual maturity of tigerfish Hydrocynus vittatus from the Okavango Delta, Botswana
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: R Gerber --- Centre for Aquatic Research, Department of Zoology, South Africa NJ Smit --- Centre for Aquatic Research, Department of Zoology, South Africa GM Pieterse --- Centre for Aquatic Research, Department of Zoology, South Africa D Durholtz --- , South AfricaThe aims of this study were to determine relative age, growth rate and size at maturity of tigerfish in the Okavango Delta as a basis for the development of a fisheries management plan. A total of 206 tigerfish Hydrocynus vittatus,... -
Cross-shelf biogeochemical characteristics of sediments in the central Benguela and their relationship to overlying water column hypoxia
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AK van der Plas PMS Monteiro A PascallData from two cross-shelf sediment sampling cruises were used to explain reasons for the sediment biogeochemical variability in respect of carbon, nitrogen and sulphur, and how the cycling of these elements governs the biogeochemistry of the overlying water through their... -
A simple implementation of the statistical modelling framework Gadget for cod in Icelandic waters
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Taylor J Begley V Kupca G StefanssonGadget is a statistical modelling framework that can be used to assess individual fish stocks and to create multispecies, multi-fleet and multi-area models. The development of a complex multispecies model requires understanding of the modelled single-species population. Simple single-species models... -
A Bayesian state-space model for mixed-stock migrations, with application to Northeast Atlantic mackerel Scomber scombrus
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CL Cunningham DG Reid MK McAllister GP Kirkwood CD DarbyManagement of fisheries that exploit mixed-stock populations relies on assumptions made concerning stock structure and mixing in different areas. To address the problems of accounting for uncertainty when formulating scientific advice for the management of highly migratory fish stocks, management... -
Chromosome number of the South African abalone Haliotis midae
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M van der Merwe R Roodt-WildingDespite the widespread distribution of the genus Haliotis, chromosome numbers are only known for a small subset of species. In South Africa, no chromosome studies have been conducted on any of the five species occurring in the region. This study... -
Comparing internal and external drivers in the southern Benguela and the southern and northern Humboldt upwelling ecosystems
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: LJ Shannon S Neira M TaylorTrophic models of three upwelling ecosystems, the southern Benguela (South African), southern Humboldt (Chilean) and northern Humboldt (Peruvian) systems, have been fitted to catch, abundance and fishing mortality time-series. Three drivers were considered during the model fitting: internal forcing by... -
The effect of marine protected areas on an exploited population of sex-changing temperate reef fish: an individual-based model
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SE Kerwath A Götz CG Attwood WHH SauerThe effect of two marine protected areas (MPAs) on roman Chrysoblephus laticeps (Sparidae), an exploited reef-fish species inhabiting the South African temperate south coast, was simulated with a spatially explicit, individual-based model based on geographically correct habitat distribution. The model... -
Changes in the trophic structure of the southern Benguela before and after the onset of industrial fishing
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: KE Watermeyer LJ Shannon CL GriffithsDespite a human presence in the Benguela region for at least one million years, exploitation of marine resources by European seafarers only began in earnest in the 1400s. Ecopath with Ecosim was used to construct and compare mass-balanced foodweb models... -
Changes in the trophic structure of the northern Benguela before and after the onset of industrial fishing
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: KE Watermeyer LJ Shannon J-P Roux CL GriffithsExploitation of marine resources has been occurring in the northern Benguela ecosystem for centuries. Understanding the cumulative long-term effects of this exploitation is important toward effective management of the modern system. Retrospective mass-balanced models of the ecosystem have been constructed,... -
The effects of ageing biases on stock assessment and management advice: a case study on Namibian horse mackerel
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MR Wilhelm MD Durholtz CH KirchnerWe explore the influence of age-estimation errors on the results of the age-structured production model (ASPM) used for horse mackerel stock assessment in Namibia for the period 1961–2003. The analysis considered age data from eight readers collected during an otolith-reading... -
Does vertical migratory behaviour retain fish larvae onshore in upwelling ecosystems? A modelling study of anchovy in the southern Benguela
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Parada C Mullon C Roy P Fréon L Hutchings CD van der LingenA spatially explicit individual-based model (IBM) forced by 3D temperature and current fields simulated by a hydrodynamic model of the southern Benguela upwelling region was used to test two hypotheses concerning the role of diel vertical migration (DVM) by Cape... -
Factors affecting recapture rates of raggedtooth sharks Carcharias taurus tagged off the east coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: ML Dicken --- Department of Ichthyology and Fisheries Science, South Africa AJ Booth --- Department of Ichthyology and Fisheries Science, South Africa MJ Smale --- , South AfricaUnderstanding differences in the recapture rate between different tags (A-, B- and C-types), capture methods (rock-and-surf anglers, scientific divers and Natal Sharks Board protection nets) and life-history stages (juvenile and adult) is critical in evaluating the results obtained from cooperative... -
Tree taper models for Cupressus lusitanica plantations in Ethiopia
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Leakemariam Berhe Göran ArnoldssonTo provide a taper model for planning and management of Cupressus lusitanica plantations in Ethiopia, seven taper models were compared. Four performance indicator statistics were used for comparing the models in their ability to estimate tree diameter, and total and... -
A model to determine the theoretical maximum feed speed of a frame saw
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: CB WesselsThe frame saw is a popular primary and secondary log breakdown saw in South Africa. In this study a theoretical model for estimating the maximum feed speed of a frame saw is derived. Contrary to earlier models, the actual blade... -
A comparison of deterministically predicted genetic gains with those realised in a South African Eucalyptus grandis breeding program
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: SD Verryn CL Snedden KA EatwellTree breeders attempt to predict the genetic gains that are likely to be achieved through selection and breeding of new generations, using stochastic or deterministic modelling. There are many factors that may cause a discrepancy between the predicted and realised... -
Climate and growth influences on wood formation and utilisation
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: GM Downes DM DrewWood is produced by a complex sequence of interactions between gene–protein expression and the local environment. It is produced by the vascular cambium, an essentially two-dimensional surface of meristematic cells covering the tree stem. The growth of any individual cambial... -
Processes influencing the population dynamics and conservation of African penguins on Dyer Island, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: K Ludynia --- Marine Research Institute, Department of Biological Sciences, South Africa LJ Waller --- Western Cape Nature Conservation Board, South Africa RB Sherley --- Marine Research Institute, Department of Biological Sciences, South Africa F Abadi --- Animal Demography Unit, Department of Biological Sciences, South Africa Y Galada --- Marine Research Institute, Department of Biological Sciences, South Africa D Geldenhuys --- Western Cape Nature Conservation Board, South Africa RJM Crawford --- Animal Demography Unit, Department of Biological Sciences, South Africa LJ Shannon --- Marine Research Institute, Department of Biological Sciences, South Africa A Jarre --- Marine Research Institute, Department of Biological Sciences, South AfricaDyer Island, South Africa, supported the largest African penguin Spheniscus demersus colony in 1979 (22 655 breeding pairs), but population dynamics of the species have not followed the trends of adjacent colonies in years of high fish abundance or shifts... -
Modelling habitat suitability in the Aquatic Warbler wintering ground Djoudj National Park area in Senegal
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Cosima Tegetmeyer --- Institute of Botany and Landscape Ecology, Germany Annett Frick --- LUP GmbH, Germany Nina Seifert --- Zoological Institute and Museum, GermanyThe only well-studied wintering ground of the globally threatened Aquatic Warbler Acrocephalus paludicola is the ‘Djoudj area’ in Senegal. This study identifies potential Aquatic Warbler habitats within that area and gives an estimate of the size of the local wintering... -
Predicting the potential distribution of invasive silver carp Hypophthalmichthys molitrix in South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: N Lübcker --- Department of Zoology and Entomology, South Africa TA Zengeya --- Department of Zoology and Entomology, South Africa J Dabrowski --- Department of Paraclinical Sciences, Faculty of Veterinary Science, South Africa MP Robertson --- Department of Zoology and Entomology, South AfricaPredicting the potential geographical distribution and spread of non-native species is of major concern to ecologists. Silver carp Hypophthalmichthys molitrix, ranked as one of the world's 100 worst invasive species, were introduced into South Africa in 1975, but the potential... -
BECVOL 3: an expansion of the aboveground biomass quantification model for trees and shrubs to include the wood component
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Nico Smit --- Animal, Wildlife and Grassland Sciences, South AfricaA quantitative description of woody plant communities that aimed at aiding studies on grass–tree competition interactions, bush encroachment and estimation of food to browser herbivore species, was proposed during 1989. It evolved as the BECVOL-model and differs from other methods... -
Percentile-based Weibull diameter distribution model for Pinus kesiya stands in Benguet province, Philippines
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Roscinto Ian C Lumbres --- Warm Temperate and Subtropical Forest Research Center, Republic of Korea Young Jin Lee --- Department of Forest Resources, Republic of KoreaThis study was conducted to develop a diameter distribution model for Pinus kesiya stands in Benguet province, Philippines, using the percentile-based Weibull model. The performance of the different equations was examined using evaluation statistics such as the fit index (FI)... -
Does Medicine Need Psycho-Social Science?
Item type: Journal Article • Journal: South African Family Practice • Authors: SWP Mhlongo --- Department of Family Medicine & Primary Health Care Medunsa, PMH Maduna --- Department of Family Medicine & Primary Health Care Medunsa,Despite Alma Ata in 1978, the developing countries continue to divert scarce resources to multiple-story tertiary hospitals at the expense of primary health care services. No country in the world has unlimited resources with regard to budget allocation for health... -
Barriers to the successful implementation of school health services in the Mpumalanga and Gauteng provinces
Item type: Journal Article • Journal: South African Family Practice • Authors: DR Mohlabi --- University of Limpopo, Medunsa campus, EJ Van Aswegen --- University of Limpopo, Medunsa campus, JD Mokoena --- University of Limpopo, Medunsa campus,Background: The level of development of a country is measured by the health status of its children. The higher the mortality and morbidity rates in children, the more the country is challenged to improve its health care system. Although South... -
Bouncing forward: families living with a type I diabetic child
Item type: Journal Article • Journal: South African Family Practice • Authors: O Brown --- Department of Psychology, Faculty of Health Sciences, South Africa P Fouché --- Department of Psychology, Faculty of the Humanities, South Africa M Coetzee --- Uitenhage Provincial Hospital, South AfricaBackground: Despite the multitude of challenges that families living with a child with diabetes face, they have been found to adapt to such an extent that diabetes is viewed as a manageable condition. This study was concerned with the factors... -
A qualitative exploratory study: Using medical students' experiences to review the role of a rural clinical attachment in KwaZulu-Natal
Item type: Journal Article • Journal: South African Family Practice • Authors: PD Mc Neill --- Facilitator at the Centre for Rural Health, LM Campbell --- School of Education, University of KwaZulu-Natal,Objectives: There are challenges when it is considered that a main role of a rural clinical attachment for medical students is to encourage students to return after graduation to practise in rural areas. This view may lead to the relative... -
The end of AIDS: Possibility or pipe dream? A tale of transitions
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Alan Whiteside --- Basillie School of International Affairs and Wilfrid Laurier University, Canada Michael Strauss --- Health Economics and HIV/AIDs Research Division (HEARD), South AfricaGlobally, in the last 20 years health has improved. In this generally optimistic setting HIV and AIDS accounts for the fastest growing burden of disease. The data show the bulk of this is experienced in Southern Africa. In this region,... -
Meaning and relational well-being: a reflection on the state of the art and a way forward
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Marié P. Wissing [cor1]This paper provides a brief overview of facets of meaning and relational well-being highlighting the foci of current research on meaning, relationships as sources of meaning, contextual relevance and meta-theoretical assumptions. Lacunae in knowledge are indicated and a model proposed... -
Emotional load and social support as indicators of bullying at work
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Leon T. de Beer --- WorkWell Research Unit, South AfricaThis study sought to ascertain whether elevated emotional load and a lack of social support could be indicative of bullying at work. Participants totalled 1442 employees from the manufacturing industry in South Africa. Data on emotional load, social support, and... -
The Human Economy Project: first steps
Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: John Sharp --- The Human Economy Project, Faculty of Humanities, South Africa Theodore Powers --- The Human Economy Project, Faculty of Humanities, South Africa Vito Laterza --- The Human Economy Project, Faculty of Humanities, South AfricaThe Human Economy Project is interdisciplinary in scope, but relies extensively on anthropological research methods. These methods are an appropriate counter to the methods adopted in mainstream economics, which has been criticised for its isolation from ‘the ordinary business of... -
Performance of simple irrigation scheduling calendars based on average weather data for annual ryegrass
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Melake K Fessehazion --- Plant Production and Soil Science, South Africa John G Annandale --- Plant Production and Soil Science, South Africa Colin S Everson --- Plant Production and Soil Science, South Africa Richard J Stirzaker --- Plant Production and Soil Science, South Africa Michael van der Laan --- Plant Production and Soil Science, South Africa Wayne F Truter --- Plant Production and Soil Science, South Africa Amanuel B Abraha --- Plant Production and Soil Science, South AfricaPoor irrigation management in pastures can lead to yield and quality reduction as well as loss of income through extra pumping and leaching of nitrate fertiliser. A number of irrigation scheduling techniques of varying levels of sophistication have been developed... -
Modelling the effects of storage temperature on the respiration rate of different pomegra nate fractions
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Wilhelmina V Aindongo --- Department of Food Science, Faculty of AgriSciences, South Africa Oluwafemi J Caleb --- Postharvest Technology Research Laboratory, South African Research Chair in Postharvest Technology, Faculty of AgriSciences, South Africa Pramod V Mahajan --- Department of Horticultural Engineering, Germany Marena Manley --- Department of Food Science, Faculty of AgriSciences, South Africa Umezuruike Linus Opara --- Postharvest Technology Research Laboratory, South African Research Chair in Postharvest Technology, Faculty of AgriSciences, South AfricaTemperature is one of the main factors that affects fresh produce respiration rate (RR). This study investigated the effects of storage temperature (5, 10, 15 and 22 °C) on the RRs of the pomegranate (Punica granatum L.) ‘Bhagwa’ whole fruit,... -
Adopting latecomers' strategies for the development of renewable energy technology in Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Maruf Sanni --- National Centre for Technology Management, Federal Ministry of Science and Technology, Obafemi Awolowo University, Nigeria Oluwatosin G Oladipo --- National Centre for Technology Management, Federal Ministry of Science and Technology, Obafemi Awolowo University, Nigeria Ibikunle O Ogundari --- National Centre for Technology Management, Federal Ministry of Science and Technology, Obafemi Awolowo University, Nigeria O Titilayo Aladesanmi --- National Centre for Technology Management, Federal Ministry of Science and Technology, Obafemi Awolowo University, NigeriaThe overall objective of this paper is to develop strategies on how renewable energy technology could be used to abate climate change impacts in Africa. While assessing the potential impacts of climate change in Africa, the paper asserts that renewable... -
Computerised inventory management for a manufacturing industry: A case study in Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Emmanuel Seye Owoeye --- Mechanical Engineering Department, Nigeria Samuel Babatope Adejuyigbe --- Mechanical Engineering Department, Nigeria Bukola Olalekan Bolaji --- Mechanical Engineering Department, Nigeria A.F. Adekoya --- Computer Science Department, NigeriaVarious authors have suggested that the cost of purchasing and holding inventory can account for as much as 60%–80% of the total cost of a product or service. Usually, only some of the inventory (about 10%) contributes to 70%–80% of... -
Innovation Policy Reforms, Emerging Role Models and Bridge Institutions: Evidence from North African Economies
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Abdelkader Djeflat --- Department of Economics, Labo Clerse UMR 8019-Maghtech Network, France Yevgeny Kuznetsov --- Economic Policy and Debt Department, Wolrd Bank, USAThis article focuses on role models of modern innovation based development and public interventions to diffuse and scale up these role models. It discusses the so-called bridge institutions of innovation, which transform skills into knowledge valued by markets. It shows... -
Bone growth patterns in two cordylid lizards, Cordylus cataphractus and Pseudocordylus capensis
Item type: Journal Article • Journal: African Zoology • Authors: Amanda J. Curtin --- Department of Zoology, South Africa P. le --- Department of Zoology, South Africa Fras N. Mouton --- Department of Zoology, South Africa Anusuya Chinsamy --- Department of Zoology, South AfricaCross-sections through the midshaft of the femora from an ontogenetic range of individuals were examined for Cordylus cataphractus, a heavily armoured, group-living lizard found in the western parts of South Africa, and Pseudocordylus capensis, an agile, montane lizard, occurring in... -
Age, growth and reproduction of largemouth bass, Micropterus salmoides, in Lake Manyame, Zimbabwe
Item type: Journal Article • Journal: African Zoology • Authors: C.A. Beamish --- Department of Ichthyology and Fisheries Science, South Africa A.J. Booth --- Department of Ichthyology and Fisheries Science, South Africa N. Deacon --- Department of Ichthyology and Fisheries Science, South AfricaA total of 478 largemouth bass, Micropterus salmoides (Lacépède, 1802), was sampled between September 1997 and July 2001 using hook-and-line in Lake Manyame, a water supply reservoir situated outside Harare, Zimbabwe. Male fish dominated the samples, possibly an effect of... -
Do deterministic processes influence the phenotypic patterns of animalivorous bat ensembles at urban rivers?
Item type: Journal Article • Journal: African Zoology • Authors: M. Corrie Schoeman --- School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, South Africa Kirby J. Waddington --- School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, South AfricaAlthough urbanization is perhaps the most damaging, persistent, and rapidly expanding form of anthropogenic pressure on natural ecosystems, data on the patterns and processes of sympatric bat species in urban landscapes are relatively scant. We quantified the packing and dispersion... -
Invertebrates or iron: does large-scale opencast mining impact invertebrate diversity in ephemeral wetlands?
Item type: Journal Article • Journal: African Zoology • Authors: Falko T. Buschke --- Centre for Environmental Management (67), University of the Free State, South Africa Joan Adendorff --- Centre for Environmental Management (67), University of the Free State, South Africa Jaco Lamprechts --- Kolomela Iron Mine, South Africa Marie Watson --- Centre for Environmental Management (67), University of the Free State, South Africa Maitland T. Seaman --- Centre for Environmental Management (67), University of the Free State, South AfricaDisturbance has been offered as an explanatory mechanism in structuring the variation of species across a landscape. In this study, we investigated the effect of the impact by Kolomela Iron Mine on the variation of species occurring in temporary pans... -
Ecosystem modelling in the southern Benguela: comparisons of Atlantis, Ecopath with Ecosim, and OSMOSE under fishing scenarios
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MD Smith --- Department of Zoology, Australia EA Fulton --- CSIRO [Commonwealth Scientific and Industrial Research Organisation], Australia RW Day --- Department of Zoology, Australia LJ Shannon --- Marine Research Institute and Department of Biological Sciences, South Africa Y-J Shin --- Marine Research Institute and Department of Biological Sciences, South AfricaEcosystem-based management of marine fisheries requires the use of simulation modelling to investigate the system-level impact of candidate fisheries management strategies. However, testing of fundamental assumptions such as system structure or process formulations is rarely done. In this study, we... -
Modelling annual evapotranspiration in a semi-arid, African savanna: functional convergence theory, MODIS LAI and the Penman–Monteith equation
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Anthony R Palmer --- Centre for African Conservation Ecology, South Africa Craig Weideman --- Department of Environmental Science, South Africa Andiswa Finca --- Agricultural Research Council–Animal Production Institute, South Africa Colin S Everson --- Bioresources Engineering and Environmental Hydrology, South Africa Niall Hanan --- Geospatial Science Center of Excellence, USA William Ellery --- Department of Environmental Science, South AfricaAccurately measuring evapotranspiration (ET) is essential if we are to derive reasonable estimates of production and water use for semi-arid savannas. Estimates of ET are also important in defining the health of an ecosystem and the quantity of water used... -
Crop model usefulness in drylands of southern Africa: an application of DSSAT
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Nkulumo Zinyengere --- Climate System Analysis Group, Department of Environmental and Geographical Science, South Africa Olivier Crespo --- Climate System Analysis Group, Department of Environmental and Geographical Science, South Africa Sepo Hachigonta --- Food Agriculture and Natural Resources Policy Analysis Network, South Africa Mark Tadross --- United Nations Development Programme – Global Environment Facility, South AfricaCrop models are useful tools for simulating impacts of climate and agricultural practices on crops. Models have to demonstrate the ability to simulate actual crop growth response in particular environments before application. Data limitations in southern Africa frequently hinder adequate... -
Growth models for six Eucalyptus species in Angola
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Cristobal Delgado-Matas --- Faculty of Agrarian Sciences, Angola Timo Pukkala --- Faculty of Science and Forestry, FinlandThis study developed growth models for Eucalyptus saligna Sm., E. camaldulensis Dehnh., E. macarthurii H.Deane & Maiden, E. resinifera Sm., E. siderophloia Benth. and E. grandis Hill ex. Maiden, for the central highlands of Angola, and used these models to... -
Modelling of product demand as a pointer tool for choice of maintenance strategy
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Michael Kanisuru Adeyeri --- Department of Industrial Engineering, South Africa Khumbulani Mpofu --- Department of Industrial Engineering, South Africa Buliaminu Kareem --- Department of Mechanical Engineering, NigeriaThe purpose of this paper is to use product demand or sales turnout of products in a competitive environment as an indicator to suggest maintenance strategies for machinery. The model takes account of singular products from several companies or industries,... -
Employing the prespecified variable approach to APT factor identification on the segmented Johannesburg Stock Exchange
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: Paul van Rensburg --- Department of Accounting and Finance,Prior research has provided evidence that the return generating process on the Johannesburg Stock Exchange (JSE) is dichotomous in nature (Campbell, 1979; Gilbertson and Goldberg, 1981;Carter, 1983; Page, 1986, 1989; Venter, Bradfield and Bowie, 1992). More specifically, this prior work... -
Financial Information Systems: Teaching REA semantics within an Information Engineering framework
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: J. Callaghan --- Professor of Accounting, School of Business Administration, United States of America A. Savage --- Assistant Professor of Accounting, School of Business Administration, United States of America E. Peacock --- Professor of Accounting, School of Business Administration, United States of AmericaThe purpose of this paper is to describe how the accounting REA model can be incorporated into the Information Engineering set of methodologies in the Accounting or Financial Information Systems classroom. We contrast the traditional Information Engineering approach with one... -
An empirical examination of the Ohlson (1995) model
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: G Swartz --- School of Accountancy, Johannesburg M Negash --- School of Accountancy, JohannesburgThis paper examines the Ohlson (1995) model and documents its validity in explaining share prices using data for 129 firms continuously listed on the Johannesburg Securities Exchange (JSE hereafter), over a twelve year period. More specifically, cross-sectional multiple regressions and... -
An argument for either excluding death as a capital gains tax event or abolishing estate duty
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: J J Roeleveld --- Department of Finance and Tax,South Africa is one of the few countries in the world that imposes both estate duty and capital gains tax on the assets of a person on death. This paper presents an argument for the abolishment of estate duty in... -
On pricing kernels, information and risk
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Diane L. Wilcox --- School of Computational & Applied Mathematics, South Africa Tim J. Gebbie --- School of Computational & Applied Mathematics, South AfricaThis paper compares out-of-sample, ex-ante risk and returns of arbitrage pricing theory (APT) risk-factor based, zero-cost portfolios with characteristic-based, zero-cost portfolios. In particular the Haugen and Baker characteristic-based model framework is used in a comparison with the capital asset pricing... -
Effects of the market factor on portfolio diversification: the case of market crashes
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Cheoljun Eom --- School of Business, Korea Jong Won Park --- College of Business Administration, Korea Yong H. Kim --- Carl H. Lindner College of Business, USA Taisei Kaizoji --- Graduate School of Arts and Sciences, JapanThis paper investigates empirically the effects of the market factor on the degree of portfolio diversification extracted from Markowitz's mean-variance (MV) model to explore an alternative method for improving the practical usefulness of the model. It controls for various properties... -
Evaluating and predicting the failure probabilities of hedge funds
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Hee Soo Lee --- Discipline of Finance, School of Business, Korea Juan Yao --- Discipline of Finance, AustraliaHedge funds have the most sophisticated risk management practices; however, they also appear to have a short lifetime relative to other managed funds. In this study we investigate the failure probabilities of hedge funds – particularly the failures due to... -
A review of capital market theory from a South African Perspective
Item type: Journal Article • Journal: De Ratione • Authors: D.J. Bradfield --- University of Cape Town,The vast quantity of finance literature dealing with Capital Market Theory on the New York Stock Exchange (NYSE) is evidence of the demand for research in this area. Until very recently, almost no research In this area has been conducted... -
A note on the estimation problems caused by thin-trading on the Johannesburg Stock Exchange
Item type: Journal Article • Journal: De Ratione • Authors: D. Bradfield --- University of Cape Town,The estimation problems caused by the effects of thin-trading are highlighted. In particular thin-trading is found to be the major cause of bias associated with the estimation of beta coefficients in smaller markets like the JSE. The empical study conducted... -
The influence of the NYSE of the risk of JSE stocks
Item type: Journal Article • Journal: De Ratione • Authors: D.J. Bradfield --- University of Cape Town,In this article the influence of the NYSE on the risk of securities on the JSE is investigated. A technique for obtainine. Risk coefficients which capture the sensitivity of securities on the JSE to movements on the NYSE is demonstrated... -
Sustainable growth and distributable earnings under inflation
Item type: Journal Article • Journal: De Ratione • Authors: J U de Villiers --- University of the Witwatersrand,This paper examines the effect of inflation on the relationship between a firm’s sustainable real growth rate and its dividend payout ratio. Ceteribus paribus, dividend payout ratios are found to decrease monotonically with increasing inflation. The extent of the decline... -
Estimating the Return Parameters of the Capital Asset Pricing Model
Item type: Journal Article • Journal: De Ratione • Authors: Colin Firer --- University of the Witwatersrand,The cost of equity capital is a fundamental concept In the field of finance. Its estimation often relies on the application of the Capital Asset Pricing Model. Very little help is offered to the practitioner in the selection of appropriate... -
Macroeconomic variables and the Johannesburg Stock Exchange: A multifactor approach
Item type: Journal Article • Journal: De Ratione • Authors: Paul Van Rensburg --- Department of Accounting,This study estimates the simultaneous relationship between a number of selected macroeconomic variables and share prices on the Johannesburg Stock Exchange (JSE). A linear factor model identical in form to that assumed by the arbitrage pricing theory (APT) is estimated... -
Further Evidence of Firm Size and Earnings Anomalies on the Johannesburg Stock Exchange
Item type: Journal Article • Journal: De Ratione • Authors: Michael J. Page --- Graduate School of Business,In spite of the large body of evidence in favour of capital market efficiency in the semi-strong form, several enigmatic findings persist. As much of the research is based on the theoretical foundation of the Capital Asset Pricing Model, the... -
Analysis of responses to work-home interaction as measured by the SWING
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Carin Hill --- Department of Industrial Psychology and People Management, South AfricaThe primary objective of this study was to analyse the responses of the Survey Work-home Interaction-Nijmegen – (SWING) using the Rasch measurement model. A quantitative, cross-sectional research design was used. Paper-and-pencil copies of the SWING were distributed to heterosexual working... -
Spatial pattern and determinants of unmet need of family planning in Nigeria
Item type: Journal Article • Journal: South African Family Practice • Authors: Oluwayemisi Oyeronke Alaba --- Department of Statistics, Nigeria JO Olaomi --- Department of Statistics, South Africa Olusanya E. Olubusoye --- Department of Statistics, NigeriaBackground: Nigeria still grapples with low family planning (FP) use and a high fertility rate. This study explores the factors associated with the unmet need for FP and the coldspots of unmet need for FP in Nigeria. -
Women, difference and urbanisation patterns in Cape Town, South Africa
Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: Andrew Spiegel --- Department of Social Anthropology, South Africa Vanessa Watson --- Department of Social Anthropology, South Africa Peter Wilkinson --- Department of Social Anthropology, South AfricaA point apparently often lost to policy makers is that those for whom policy is designed have very diverse life experiences. The article focuses on two women's experiences of urbanisation: experiences that are extremely different from one another, despite the... -
Stakeholders and stickholders: power and paradigms in a South African development context
Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: Sarah A. Bologna --- Department of Social Anthropology, South AfricaThe alluring vision that ecotourism can drive both rural development and ecological objectives has taken deep root in post-apartheid South Africa where severe economic inequalities persist as a result of dispossession and grossly restricted access to resources during the colonial... -
The Human Economy Project: first steps
Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: John Sharp --- The Human Economy Project, Faculty of Humanities, South Africa Theodore Powers --- The Human Economy Project, Faculty of Humanities, South Africa Vito Laterza --- The Human Economy Project, Faculty of Humanities, South AfricaThe Human Economy Project is interdisciplinary in scope, but relies extensively on anthropological research methods. These methods are an appropriate counter to the methods adopted in mainstream economics, which has been criticised for its isolation from ‘the ordinary business of... -
Modelling primary branch growth based on a multilevel nonlinear mixed‑effects model: a Pinus koraiensis plantation case study in north‑east China
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Lingbo Dong --- Department of Forest Management, College of Forestry, China Zhaogang Liu --- Department of Forest Management, College of Forestry, China Fengri Li --- Department of Forest Management, College of Forestry, China Lichun Jiang --- Department of Forest Management, College of Forestry, ChinaOn the basis of a multilevel nonlinear mixed‑effects model approach, branch diameter and length growth models were developed for a Pinus koraiensis plantation in north‑east China. The models developed were able to better capture the residual variation successfully by partitioning... -
Current conservation status of the Blue Swallow Hirundo atrocaerulea Sundevall 1850 in Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Steven W Evans --- SARCHI Chair on Biodiversity Value and Change, School of Mathematical and Natural Sciences, South Africa Ara Monadjem --- Department of Biological Sciences, South Africa Lizanne Roxburgh --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa Andrew E McKechnie --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, Department of Zoology and Entomology, South Africa Ellizabeth M Baker --- Tanzanian Bird Atlas Project, United Republic of Tanzania Robert B Kizungu --- Organisation of Biodiversity Information and Conservation in Congo Kinshasa, Democratic Republic of Congo Ian T Little --- Endangered Wildlife Trust, South Africa Fadzai Matsvimbo --- BirdLife Zimbabwe, Zimbabwe Ronald K Mulwa --- National Museums of Kenya and Nature Kenya, Kenya Daniel Mwizabi --- Zambian Wildlife Authority, Zambia Dianah Nalwanga --- Nature Uganda, Uganda Kariuki Ndang'ang'a --- BirdLife International, Africa Partnership Secretariat, Kenya Leigh Combrink --- Endangered Wildlife Trust, South AfricaThe global Blue Swallow Hirundo atrocaerulea was classified as Vulnerable in 2010 on account of its small and rapidly declining population estimated at less than 1 500 pairs. We undertook this study to gain a better understanding of the current... -
Social models of HIV risk among young adults in Lesotho
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Nicola L. Bulled --- Center for Global Health, USAExtensive research over the past 30 years has revealed that individual and social determinants impact HIV risk. Even so, prevention efforts focus primarily on individual behaviour change, with little recognition of the dynamic interplay of individual and social environment factors... -
Abundance and degree of residency of humpback dolphins Sousa plumbea in Mossel Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: BS James --- Mammal Research Institute, South Africa MN Bester --- Mammal Research Institute, South Africa GS Penry --- Mammal Research Institute, South Africa E Gennari --- Oceans Research, South Africa SH Elwen --- Mammal Research Institute, South AfricaIndian Ocean humpback dolphins Sousa plumbea inhabit nearshore waters from South Africa to eastern India. Humpback dolphins are vulnerable to conservation threats due to their naturally small population sizes and use of nearshore habitats, where human activities are highest. We... -
The spiritual wellness of Beyers Naudé: A psychobiographical study of a South African anti-apartheid theologian
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Paul Fouché --- Department of Psychology, Faculty of Humanities, South Africa Barbara Burnell --- Department of Psychology, Faculty of Humanities, South Africa Roelf van Niekerk --- Department of Industrial and Organisational Psychology, South AfricaThe study explores and describes Beyers Naudé's (1915–2004) spiritual wellness across his lifespan. Naudé's life history was uncovered through the systematic collection and analyses of life history materials. Data were interpreted applying the Wheel of Wellness model (WoW) by Sweeney... -
Review and empirical comparison of joint mapping of multiple diseases
Item type: Journal Article • Journal: Southern African Journal of Epidemiology and Infection • Authors: Samuel Manda --- Biostatistics Unit, South African Medical Research Council, South Africa Richard Feltbower --- Centre for Epidemiology and Biostatistics, Leeds Institute of Genetics and Therapeutics, University of Leeds, United Kingdom Mark Gilthorpe --- Centre for Epidemiology and Biostatistics, Leeds Institute of Genetics and Therapeutics, University of Leeds, United KingdomThere has been a substantial amount of recent modelling work in multivariate disease-mapping models in epidemiology. These models provide information on similarities, as well as differences, on the effect of risk factors among diseases. Additionally, they can be used to... -
Application of geographical information system and remote sensing in malaria research and control in South Africa: a review
Item type: Journal Article • Journal: Southern African Journal of Infectious Diseases • Authors: Abiodun Morakinyo Adeola --- Department of Geography, Geoinformatics and Meteorology, South Africa Joel O Botai --- Department of Geography, Geoinformatics and Meteorology, South Africa Jane Mukarugwiza Olwoch --- South African Space Agency (SANSA), Earth Observation Directorate, South Africa Hannes CJ de W Rautenbach --- Department of Geography, Geoinformatics and Meteorology, South Africa Ahmed M Kalumba --- Department of Geography, Geoinformatics and Meteorology, South Africa Philemon L Tsela --- Department of Geography, Geoinformatics and Meteorology, South Africa Mayowa Omolola Adisa --- Department of Geography, Geoinformatics and Meteorology, South Africa Nsubuga Francis Wasswa --- Department of Geography, Geoinformatics and Meteorology, South Africa Paul Mmtoni --- Department of Geography, Geoinformatics and Meteorology, South Africa Ausi Ssentongo --- Department of Geography, Geoinformatics and Meteorology, South AfricaThis paper presents a review of numerous items of published literature on the use of spatial technology for malaria epidemiology in South Africa between 1930 and 2013. In particular, focus is on the use of statistical and mathematical models as... -
Entrepreneurial innovations for agricultural mechanisation in Zimbabwe: Evidence from an informal metal industry survey
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Kingstone Mujeyi --- Department of Agricultural Economics, Zimbabwe Jackqueline Mutambara --- Department of Agricultural Economics and Extension, Zimbabwe Shephard Siziba --- Department of Agricultural Economics and Extension, Zimbabwe Wilbert Z. Sadomba --- Centre for Applied Social Sciences, Zimbabwe Tarisai K. Manyati --- Department of Sociology, ZimbabweThis study uses data collected from 602 randomly selected informal metal industry entrepreneurs across 15 cluster-sampled districts in eight of Zimbabwe's 10 provinces to analyse factors that influence technological innovations development by informal agribusiness entrepreneurs. It applies a binary logistic... -
Abundance and activity patterns of the Cape parrot (Poicephalus robustus) in two afromontane forests in South Africa
Item type: Journal Article • Journal: African Zoology • Authors: J.O. Wirminghaus --- School of Botany & Zoology, University of Natal, South Africa Colleen T. Downs --- School of Botany & Zoology, University of Natal, South Africa M.R. Perrin --- School of Botany & Zoology, University of Natal, South Africa C.T. Symes --- School of Botany & Zoology, University of Natal, South AfricaBehaviour, movements and numbers of the rare Cape parrot (Poicephalus robustus) were investigated at two study sites to assess its conservation status and as the basis for an action plan for their conservation. Birds flew regularly to and from nearby... -
Adult African sharptooth catfish, Clarias gariepinus, population dynamics in a small invaded warm-temperate impoundment
Item type: Journal Article • Journal: African Zoology • Authors: Anthony J. Booth --- Department of Ichthyology and Fisheries Science, South Africa Graham R.L. Traasg --- Department of Ichthyology and Fisheries Science, South Africa Olaf L.F. Weyl [AN0002]African sharptooth catfish, Clarias gariepinus, is a successful aquatic invader as it has a eurytopic physiology, is highly fecund, grows quickly and has an omnivorous diet. Despite possible threats that include predation of and competition with indigenous species, habitat degradation,... -
Late Pleistocene potential distribution of the North African sengi or elephant-shrew Elephantulus rozeti (Mammalia: Macroscelidea)
Item type: Journal Article • Journal: African Zoology • Authors: Árpád S. Nyári --- Natural History Museum and Biodiversity Research Center, U.S.A. Townsend A. Peterson&yg --- Natural History Museum and Biodiversity Research Center, U.S.A. Galen B. Rathbun --- Department of Ornithology and Mammalogy, California Academy of Sciences, U.S.A.The Sahara Desert was recently proposed as the agent of vicariant speciation in the North African elephant-shrew (order Macroscelidea, Elephantulus rozeti). Based on evidence from molecular dating, however, this speciation event was estimated as having occurred in the Miocene, an... -
Biomass equations for selected drought-tolerant eucalypts in South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Darius Phiri --- Department of Forest and Wood Science, South Africa Pierre Ackerman --- Department of Forest and Wood Science, South Africa Brand Wessels --- Department of Forest and Wood Science, South Africa Ben du Toit --- Department of Forest and Wood Science, South Africa Marie Johansson --- Department of Building Technology, Sweden Harald Säll --- Department for Forestry and Wood Technology, Sweden Sven-Olof Lundqvist --- Wood and Fibre Measurement Laboratory, Innventia AB, Sweden Thomas Seifert --- Department of Forest and Wood Science, South AfricaIn the water-scarce environment of South Africa, drought-tolerant eucalypt species have the potential to contribute to the timber and biomass resource. Biomass functions are a necessary prerequisite to predict yield and carbon sequestration. In this study preliminary biomass models for... -
Modelling dominant height growth in plantations of Pseudotsuga menziesii (Mirb.) Franco in Spain
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Carlos A López-Sánchez --- Instituto de Silvicultura e Industria de la Madera, México Juan G Álvarez-González --- Departamento de Ingeniería Agroforestal, Escuela Politécnica Superior, Spain Ulises Diéguez-Aranda --- Departamento de Ingeniería Agroforestal, Escuela Politécnica Superior, Spain Roque Rodríguez-Soalleiro --- Departamento de Producción Vegetal, Escuela Politécnica Superior, SpainA model for predicting dominant height growth and site index of Pseudotsuga menziesii (Mirb.) Franco in Spain was constructed. Data from stem analysis of 117 site trees were used. Four dynamic equations using the algebraic difference approach (ADA) and its... -
Biophysical models of larval dispersal in the Benguela Current ecosystem
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Lett --- UMI IRD 209 UPMC UMMISCO, Centre de Recherche Halieutique Méditerranéenne et Tropicale, France CD van der Lingen --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries, South Africa BR Loveday --- Remote Sensing Group, Plymouth Marine Laboratory, UK CL Moloney --- Marine Research Institute and Department of Biological Sciences, South AfricaWe synthesise and update results from the suite of biophysical, larval-dispersal models developed in the Benguela Current ecosystem. Biophysical models of larval dispersal use outputs of physical hydrodynamic models as inputs to individual-based models in which biological processes acting during... -
Chemotaxonomic investigation of phytoplankton in the shelf ecosystem of the KwaZulu-Natal Bight, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RG Barlow --- Bayworld Centre for Research and Education, South Africa T Lamont --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa M-J Gibberd --- Marine Research Institute and Department of Oceanography, South Africa M van den Berg --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa K Britz --- Branch: Oceans and Coasts, Department of Environmental Affairs, South AfricaPhytoplankton community structure was elucidated during summer and winter in the KwaZulu-Natal Bight using pigment and CHEMTAX analyses. The surface pattern in January 2010 indicated that diatoms, haptophytes and prasinophytes tended to be the most prominent groups inshore and in... -
Environmental influence on phytoplankton production during summer on the KwaZulu-Natal shelf of the Agulhas ecosystem
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Lamont --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa RG Barlow --- Bayworld Centre for Research and Education, South AfricaDuring February 2010, studies of primary production (PP) and physiology were conducted at five selected sites in the KwaZulu-Natal (KZN) Bight of the Agulhas ecosystem as part of a programme to elucidate the influence of major physical driving forces and... -
Modelling the Zambezi River plume
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: FPJ Nehama --- Department of Oceanography, South Africa CJC Reason --- Department of Oceanography, South AfricaA model for the Zambezi River plume, the largest on the Indian Ocean coast of Africa, is presented and the results of experiments with different discharges and wind forcings are analysed. Although the river plays an important role in the... -
Using Rasch modelling to examine the international personality item pool (IPIP) values in action (VIA) measure of character strengths
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Graham A. du Plessis --- Department of Psychology, South Africa Gideon P. de Bruin --- Department of Psychology, South AfricaThis paper investigates the psychometric properties of the values in action (VIA) character strengths (Peterson and Seligman, 2004). A sample of 904 South African undergraduate students (female=77%, male=23%, black=70%, mean age=21.07 years, SD age=2.73 years) was assessed using a 380-item... -
The Shockley five-parameter model of a solar cell: A short note
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: H.A. Koffi --- Department of Physics, Ghana A. Kuditcher --- Department of Physics, Ghana V.C.K. Kakane --- Department of Physics, Ghana E.A. Armah --- Department of Physics, Ghana A.A. Yankson --- Department of Physics, Ghana J.K.A. Amuzu --- Department of Physics, GhanaThis paper is concerned with an alternative formulation of the Shockley five-parameter model of a solar cell. This formulation leads to an explicit relationship between the short-circuit current and the light-generated current and the direct determination of the light-generated current... -
Total tree, merchantable stem and branch volume models for miombo woodlands of Malawi
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Daud J Kachamba --- Department of Ecology and Natural Resource Management, Norway Tron Eid --- Department of Ecology and Natural Resource Management, NorwayThe objective of this study was to develop general (multispecies) models for prediction of total tree, merchantable stem and branch volume including options with diameter at breast height (dbh) only, and with both dbh and total tree height (ht), as... -
Spatial characterisation of the Benguela ecosystem for ecosystem-based management
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SP Kirkman --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa L Blamey --- Marine Research Institute, South Africa T Lamont --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa JG Field --- Marine Research Institute, South Africa G Bianchi --- Food and Agriculture Organization, Italy JA Huggett --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa L Hutchings --- Marine Research Institute, South Africa J Jackson-Veitch --- Marine Research Institute, South Africa A Jarre --- Marine Research Institute, South Africa C Lett --- Institut de Recherche pour le Développement [IRD], UMR MARBEC 248, France MR Lipiński --- Department of Ichthyology and Fisheries Science, South Africa SW Mafwila --- Department of Fisheries and Aquatic Sciences, Namibia MC Pfaff --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa T Samaai --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa LJ Shannon --- Marine Research Institute, South Africa Y-J Shin --- Marine Research Institute, South Africa CD van der Lingen --- Marine Research Institute, South Africa D Yemane --- Marine Research Institute, South AfricaThe three countries of the Benguela Current Large Marine Ecosystem (BCLME), namely Angola, Namibia and South Africa, have committed to implementing ecosystem-based management (EBM) including an ecosystem approach to fisheries (EAF) in the region, to put in practice the principles... -
Escapism motive for sport consumption as a predictor of meaning in life
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Frederick W. Stander --- Optentia Research Focus Area, South AfricaThe objective of this study was to examine whether spectator escapism motive for sport consumption could predict meaning in life, and to explore the role of psychological ownership in this relationship. A sample of 806 football spectators (African = 85%,... -
Psychological ownership in relation to workplace trust and turnover intent
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Chantal Olckers --- Department of Human Resource Management, Claire Enslin --- Department of Human Resource Management,The study investigated the relationship between workplace trust, psychological ownership and turnover intent within a South African professional services organisation. A cross-sectional quantitative survey design was used to collect data from a purposive sample (n = 302) of skilled, highly... -
Monitoring eucalypt bud temperature using mobile temperature loggers
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Robin AW Gardner --- Institute for Commercial Forestry Research, South Africa Michael J Savage --- Agrometeorology Discipline, School of Agricultural, Earth and Environmental Sciences, South Africa Isa Bertling --- Horticultural Science Discipline, School of Agricultural, Earth and Environmental Sciences, South AfricaWinter chilling is a key environmental trigger of floral induction in temperate Eucalyptus. Over the past two decades, considerable site × eucalypt flowering interaction research has been undertaken over a range of high elevation (>1 100 m asl) forestry sites in... -
The development of a human resource management (HRM) professional competence model: A pilot study
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Nico Schutte --- Department of Industrial Psychology, South Africa Nicolene Barkhuizen --- Department of Industrial Psychology, South Africa Lidewey van der Sluis --- Nyenrode Business University, The Netherlands, Department of Industrial Psychology,This study sought to develop and test a diagnostic tool for the measurement of professional human resource management (HRM) competencies in the South African context. Data on HRM competencies were collected from South African human resource (HR) practitioners (N =... -
Choice in HIV testing: the acceptability and anticipated use of a self-administered at-home oral HIV test among South Africans
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Elizabeth A Kelvin --- City University New York Graduate School of Public Health and Health Policy, City University of New York, USA Sonia Cheruvillil --- City University New York Graduate School of Public Health and Health Policy, City University of New York, USA Stephanie Christian --- City University New York Graduate School of Public Health and Health Policy, City University of New York, USA Joanne E Mantell --- Division of Gender, Health and Sexuality, HIV Center for Clinical and Behavioral Studies, New York State Psychiatric Institute and Department of Psychiatry, USA Cecilia Milford --- MatCH Research (Maternal, Adolescent and Child Health Research), Department of Obstetrics and Gynaecology, South Africa Letitia Rambally-Greener --- MatCH Research (Maternal, Adolescent and Child Health Research), Department of Obstetrics and Gynaecology, South Africa Nzwakie Mosery --- MatCH Research (Maternal, Adolescent and Child Health Research), Department of Obstetrics and Gynaecology, South Africa Ross Greener --- MatCH Research (Maternal, Adolescent and Child Health Research), Department of Obstetrics and Gynaecology, South Africa Jennifer A Smit --- MatCH Research (Maternal, Adolescent and Child Health Research), Department of Obstetrics and Gynaecology, South AfricaCombination HIV prevention is being widely promoted by funders. This strategy aims to offer HIV prevention choices that can be selected and combined to decrease HIV risk in ways that fit with each individual’s situation. Treatment as prevention and pre-exposure... -
Modelling the effects of petroleum product contaminated sand on the compressive strength of concretes using fuzzy logic and artificial neural networks: A case study of diesel
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Chidozie Chukwuemeka Nwobi-Okoye --- Faculty of Engineering, Nigeria Ikechukwu Etienne Umeonyiagu --- Department of Civil Engineering, NigeriaIn this study an artificial neural network (ANN) and fuzzy logic (FL) were used to predict the compressive strength of concrete produced with diesel contaminated sand. Concrete was produced using sand contaminated with diesel at 0, 0.5, 1, 1.5, 2,... -
A brief overview of the ACEP project: Ecosystem Processes in the KwaZulu-Natal Bight
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: ST Fennessy --- Oceanographic Research Institute, South Africa MJ Roberts --- Branch: Oceans and Coasts, South Africa AW Paterson --- South African Institute for Aquatic Biodiversity, South AfricaThis introductory paper lays the basis for this supplementary issue by briefly presenting the state of knowledge on the KwaZulu-Natal (KZN) Bight at the start of this multi-disciplinary, multi-institutional, ship-based research project that ran from 2009 to 2013. The rationale... -
Physical activity and psychosomatic-related health problems as correlates of quality of life among university students
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Stefan Kruger --- Tourism Research in Economic Environs and Society (TREES), Energy Sonono --- ‘Workwell’, South AfricaThis study aimed to investigate the role of psychosomatic problems in the relationship between physical activity and healthrelated quality of life. Participants were a convenience sample of 703 students from a South African university (males = 38.8%, females = 61.2%,... -
Promoting fan engagement: An exploration of the fundamental motives for sport consumption amongst premier league football spectators
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Frederick W. Stander --- Optentia Research Focus Area, South Africa Llewellyn E. Van Zyl --- Optentia Research Focus Area, South Africa Kemiso Motaung --- North-West University Kaizer Chiefs Innovation Centre,The aim of this study was to examine whether fan engagement could be predicted by the motivational dimensions of sport consumption. A sample of 806 football sport fans (African = 85%, male = 67.4%, part of an organised supporters club... -
Sorghum production systems and constraints, and coping strategies under drought-prone agro-ecologies of Ethiopia
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Beyene A Amelework --- African Centre for Crop Improvement, South Africa Hussein A Shimelis --- African Centre for Crop Improvement, South Africa Pangirayi Tongoona --- West African Centre for Crop Improvement, College of Basic and Applied Sciences, Ghana Fentahun Mengistu --- Ethiopian Institute of Agricultural Research, Ethiopia Mark D Laing --- African Centre for Crop Improvement, South Africa Dawit Getnet Ayele --- School of Mathematics, Statistics and Computer Science, South AfricaSorghum is one of the most important cereal crops worldwide after wheat, rice, maize and barley. Examining the present socio-economic conditions of sorghum-producing farmers in different agro-ecologies in Ethiopia is of importance for the design of improvement strategies. The objectives... -
Sharks caught in the KwaZulu-Natal bather protection programme, South Africa. 13. The tiger shark Galeocerdo cuvier
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: ML Dicken --- KwaZulu-Natal Sharks Board, Umhlanga Rocks, South Africa G Cliff --- KwaZulu-Natal Sharks Board, Umhlanga Rocks, South Africa H Winker --- South African National Biodiversity Institute, South AfricaThe current study provides long-term catch rate and biological data for tiger sharks Galeocerdo cuvier caught in the KwaZulu-Natal bather protection programme. Between 1978 and 2014, 1 760 G. cuvier were caught in nets and between 2007 and 2014, 108... -
Modelling photovoltaic modules by a numerical method and artificial neural networks
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Zahra Meziani --- Department of Electronics, Faculty of Technology, Algeria Zohir Dibi --- Department of Electronics, Faculty of Technology, AlgeriaThis paper proposes modelling approaches for photovoltaic (PV) modules with a fast and simple numerical method of modelling, the Newton–Raphson method, as the first step. This method has several electric circuit models. We selected and tested the two most convincing... -
Modelling growth behaviour in monoculture in subtropical eastern Australia of two eucalypt species that differ in shade tolerance
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Philip W West --- Forest Research Centre, School of Environment, Science and Engineering, Australia Kevin Glencross --- Forest Research Centre, School of Environment, Science and Engineering, Australia J Doland Nichols --- Forest Research Centre, School of Environment, Science and Engineering, AustraliaGrowth behaviour of the relatively shade-intolerant species Eucalyptus dunnii and the rather more shade-tolerant Corymbia citriodora was considered during several growth periods over 8–14 years of age in experimental plantation monoculture in subtropical New South Wales. Larger trees dominated growth... -
The sensitivity of Afromontane tarns in the Maloti-Drakensberg region of South Africa and Lesotho to acidic deposition
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JA Dunnink --- Centre in Water Research and Development (CiWaRD) and Department of Geography, South Africa CJ Curtis --- Centre in Water Research and Development (CiWaRD) and Department of Geography, South Africa JP Beukes --- Unit for Environmental Sciences and Management, South Africa PG van Zyl --- Unit for Environmental Sciences and Management, South Africa J Swartz --- Unit for Environmental Sciences and Management, South AfricaDespite their remoteness from sources of atmospheric pollutant emissions, the Afromontane tarns in the Maloti-Drakensberg region are perfect candidates to study the negative effects of acidifying atmospheric pollution, because mountain lakes are widely recognised as sentinel ecosystems, unimpacted by direct... -
Using stable isotope analysis to study the diet of Gilchristella aestuaria larvae: preliminary insights into the foodwebs of six South African estuaries
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: D Costalago --- Department of Ecology, Environment and Plant Sciences, Sweden NAF Miranda --- DST/NRF Research Chair in Shallow Water Ecosystems, Department of Zoology, South Africa NA Strydom --- Department of Zoology, South Africa R Perissinotto --- DST/NRF Research Chair in Shallow Water Ecosystems, Department of Zoology, South AfricaSouth African estuarine systems are becoming increasingly altered by anthropogenic and environmental factors, but the consequences of such changes for these systems are still not fully understood. The most common approach for evaluating the ecological status of aquatic systems is... -
Is the grazing tolerance of mesic decreaser and increaser grasses altered by soil nutrients and competition?
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Craig D Morris --- Agricultural Research Council – Animal Production Institute (ARC-API), South AfricaAn ability to tolerate recurrent defoliation likely plays a role in the compositional shift from decreaser to increaser species with overgrazing of mesic grassland, but the grazing tolerance of local species has not been extensively studied. The growth response of... -
Achieving preferred customer status in the Dutch plastics recycling industry
Item type: Journal Article • Journal: Research in Hospitality Management • Authors: Klaes Eringa --- Stenden Hotel Management School, The Netherlands Rink Groenveld --- School of Commerce, The NetherlandsThe aim of this research is to gain insight into the aspects and processes in the Dutch plastic recycling industry which might lead to a preferred customer status and acquiring benefits once the status has been reached. The whole process... -
On the group of self-homotopy equivalences of an almost formal space
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Mahmoud Benkhalifa --- University of Sharjah, UAEA simply connected CW-complex X of finite type is called almost formal if and if the rational Hurewicz homomorphism is injective for every n ≥ 1. In this paper, we show that the group of self-homotopy equivalences of an almost... -
Indirect methods of tree biomass estimation and their uncertainties
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Marco A Njana --- Tanzania Forest Services Agency, TanzaniaTree aboveground biomass (AGB) may be determined using direct (weighing or biomass models) and indirect (involving the use of a form factor [FF]) or volume models, basic density [BD] and biomass expansion factor [BEF]) methods. Focusing on three dominant mangrove... -
Modelling diameter growth, mortality and recruitment of trees in miombo woodlands of Tanzania
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Wilson A Mugasha --- Department of Ecology and Natural Resource Management, Norway Tron Eid --- Department of Ecology and Natural Resource Management, Norway Ole M Bollandsås --- Department of Ecology and Natural Resource Management, Norway Lawrence Mbwambo --- Tanzania Forestry Research Institute, TanzaniaMiombo woodlands cover large areas in Tanzania but very little reliable data on forest dynamics for the woodlands exist. The main objective of this study was to develop a model system describing such dynamics based on easily measurable tree variables... -
Decision-support tool for management of miombo woodlands: a matrix model approach
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Wilson A Mugasha --- Department of Ecology and Natural Resource Management, Norway Ole M Bollandsås --- Department of Ecology and Natural Resource Management, Norway Terje Gobakken --- Department of Ecology and Natural Resource Management, Norway Eliakimu Zahabu --- Department of Forest Mensuration and Management, Tanzania Josiah Z Katani --- Department of Forest Mensuration and Management, Tanzania Tron Eid --- Department of Ecology and Natural Resource Management, NorwayRational forest management planning requires information on the present forest state and on future development. However, forest management planning in Tanzania has often been done without any information on forest development because appropriate tools are lacking. This study presents a... -
Managing and improving data quality through the adoption of data warehouse in the public sector
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Edzai Kademeteme --- Department of Informatics, South Africa Billy Mathias Kalema --- Department of Informatics, South Africa Pieter Pretorius --- Department of Informatics, South AfricaThe increasing use of technology in organizations has resulted in burgeoning sizes of data, a wider variety of data sources and diverse data structure, all calling for better storage, retrieval and analytics. The increasing demands that data make on organizations,... -
Equilibrium sorption isotherms of Moringa oleifera leaves at different temperatures
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Sunday Samuel Sobowale --- Department of Food Technology, Nigeria Moruf Olanrewaju Oke --- Department of Food Science and Engineering, Nigeria Lukumon Ayinde Odunmbaku --- Department of Food Technology, Nigeria Oluwafemi Ayodeji Adebo --- Department of Biotechnology and Food Technology, Faculty of Science, South AfricaAdsorption and desorption isotherms for Moringa oleifera leaves were investigated using concentrated H2SO4 solutions to vary the micro-climate over different temperatures (27, 32, 37°C) and water activity (aw) (0.1–0.8). Plots of equilibrium moisture content (EMC) against aw were used to... -
Model for cutting force prediction in high precision single-point diamond turning of optical silicon
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: M. K. O. Ayomoh --- Mechatronics Engineering Department, South Africa K. A. Abou-El-Hossein --- Mechatronics Engineering Department, South Africa O. A. Olufayo --- Mechatronics Engineering Department, South AfricaThis paper presents a mathematical model predicated on a finite series convergent scheme and derivative functions of multi-variants obtained from a cutting force constitutive equation for onward prediction of the maximum cutting force at the tip of a single-point diamond... -
Accounting for revenue using an accountability and business model framework: The case of the South African Institute of Chartered Accountants’ professional examinations
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: Warren Maroun --- School of Accountancy, South AfricaThis research adopts a normative approach. It builds on the academic literature which argues that the usefulness of financial reporting can be enhanced by aligning accounting for balances and transactions with an organisation’s business model, as presented in its integrated... -
The Internationalization of African Small and Medium Enterprises (SMEs): A South-North Pattern
Item type: Journal Article • Journal: Africa Journal of Management • Authors: Everlyne Misati --- Florida International University, USA Fred O. Walumbwa --- Florida International University, USA Somnath Lahiri --- Illinois State University, USA Sumit K. Kundu --- Florida International University, USADespite the growing internationalization of small and medium enterprises (SMEs) from Africa, related research remains limited. Adopting a qualitative approach, this study investigates three SMEs in the African coffee subsector that internationalized rapidly beyond the continent. The case studies, based... -
Long-run adjustment of size, value, momentum and growth premium in equity returns: Evidence from South Asian emerging markets
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Adnan Shoaib --- Management Sciences, Pakistan Muhammad Ayub Siddiqui --- FAST School of Management, PakistanThis study scrutinizes the long-run adjustment of risk premiums in equity returns of the emerging stock markets of Pakistan, China and India, the three emerging South Asian economies, by keeping in view leading contributions of the Fama and French (1992)... -
The relative importance of climatic gradient versus human disturbance in determining population structure of Afzelia africana in the Republic of Benin
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Achille E Assogbadjo --- Laboratory of Applied Ecology, Faculty of Agronomic Sciences, Republic of Benin Sylvanus Mensah --- Laboratory of Biomathematics and Forest Estimations, Faculty of Agronomic Sciences, Republic of Benin Romain Glèlè Kakaï --- Laboratory of Biomathematics and Forest Estimations, Faculty of Agronomic Sciences, Republic of BeninThe study aimed to investigate the relative significance of effects of climatic variability and human disturbance on the population structure of the threatened species Afzelia africana Sm. ex Pers. in the Republic of Benin in West Africa. Forest inventory data... -
Manganese adsorption by sediment in Wadi Tafna, Algeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: N Dali-Youcef --- Department of Ecology and Environment, Algeria B Ouddane --- UFR of Chemistry, France Z Derriche --- Department of Chemistry, AlgeriaThe removal of manganese from aqueous solution by sediment in Wadi Tafna, north-western Algeria, was investigated under batch conditions in 2003. Kinetic data equilibrium removal isotherms were measured at 20 °C. The influence of different experimental parameters, such as contact... -
Genetic variation in survival, growth, and stem form of Pinus leiophylla in Brazil and South Africa and provenance resistance to pitch canker
Item type: Journal Article • Journal: Southern Hemisphere Forestry Journal • Authors: WS Dvorak GR Hodge JE KietzkaPinus leiophylla is a relatively common pine that occurs in the mountains of western and central Mexico. Between 1987 and 1990, Camcore, North Carolina State University, sampled 11 populations and 309 mother trees of the species to determine patterns of... -
Bark thickness and bark volume of Pinus patula in South Africa
Item type: Journal Article • Journal: Southern Hemisphere Forestry Journal • Authors: A. van LaarIn South Africa, tree volume tables and volume functions are usually based on the under bark stem volume. Many forest management studies, however, give the estimated over bark volume, in which case equations are required that estimate bark volume and... -
The potential of NIRs as a non-destructive post-harvest quality assessment tool for ‘Triumph’ persimmon fruit
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Pesanai Zanamwe --- Department of Botany and Biotechnology, South AfricaThe potential of near-infrared spectroscopy (NIRs) as an alternative non-destructive post-harvest quality assessment tool for ‘Triumph’ persimmon fruit was assessed. Fruits were harvested at four stages of maturity and each stage was replicated four times. Fruit quality was assessed at... -
Photosynthesis versus irradiance relationships in the Atlantic sector of the Southern Ocean
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Thomalla --- Ocean Systems and Climate Group, South Africa E Kean --- Biological Sciences Department, South Africa M Lucas --- Biological Sciences Department, South Africa M-J Gibberd --- Biological Sciences Department, South Africa R Barlow --- Department of Oceanography, South AfricaEleven incubation experiments were conducted in the South Atlantic sector of the Southern Ocean to investigate the relationship between new production (ρNO–3), regenerated production (ρNH+4), and total carbon production (ρC) as a function of varying light. The results show substantial... -
Ecology and behaviour of Palm-nut Vultures Gypohierax angolensis in the Bijagós Archipelago, Guinea-Bissau
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Camilo Carneiro --- Department of Biology and CESAM, Portugal Mohamed Henriques --- Faculty of Sciences, Portugal Castro Barbosa --- Institute of Biodiversity and Protected Areas of Guinea-Bissau, Guinea-Bissau Quintino Tchantchalam --- Institute of Biodiversity and Protected Areas of Guinea-Bissau, Guinea-Bissau Aissa Regalla --- Institute of Biodiversity and Protected Areas of Guinea-Bissau, Guinea-Bissau Ana R Patrício --- Centre for Ecology and Conservation, UK Paulo Catry --- MARE – Marine and Environmental Sciences Centre, PortugalPopulations of many vulture species have undergone substantial declines. In Africa, 82% are threatened and although research on vultures has increased, the biology and ecology of several species is still poorly known. The Palm-nut Vulture Gypohierax angolensis has peculiar ecological... -
Partnership duration, concurrency, and HIV in sub-Saharan Africa
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Larry Sawers --- Department of Economics, USA Alan Isaac --- Department of Economics, USAA widely accepted explanation for the exceptionally high HIV prevalence in sub-Saharan Africa is the practice of long-term overlapping heterosexual partnering. This article shows that long-duration concurrent partnering can be protective against HIV transmission rather than promoting it. Monogamous partnering... -
Improvement of spatial modelling of crop suitability using a new digital soil map of Tanzania
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Kristin Piikki --- International Center for Tropical Agriculture (CIAT), Kenya Leigh Winowiecki --- World Agroforestry Centre (ICRAF), Kenya Tor-Gunnar Vågen --- World Agroforestry Centre (ICRAF), Kenya Julian Ramirez-Villegas --- International Center for Tropical Agriculture (CIAT), Colombia Mats Söderström --- International Center for Tropical Agriculture (CIAT), KenyaClimate change is projected to have widespread impacts on the climate suitability and geographical distribution of agricultural crops. Simulations were conducted on the suitability of common beans (Phaseolus vulgaris L.) in Tanzania under progressive climate change, taking into account a... -
Public perceptions about renewable energy technologies in Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Rosemary N. Wojuola --- School of Education, South Africa Busisiwe P. Alant --- School of Education, South AfricaGlobally, there is a focus on generating energy from renewable energy sources in order to ensure sustainability. However, experience has shown that although the public generally accepts renewable energy technology (RET), there is also opposition to its implementation. Renewable energy... -
Exploring the validity of scores from the Rosenberg Self-Esteem Scale (RSES) in Burundi: A multi-strategy approach
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Anne Fromont --- School of Public Health, Belgium Slim Haddad --- Research Unit, Canada Rolf Heinmüller --- External consultant, Canada Bruno T. Dujardin --- School of Public Health, Belgium Annalisa Casini --- Psychological Sciences Research Institute, BelgiumThe present study aimed to validate the Rosenberg Self-Esteem Scale (RSES) in Burundi, through a multi-strategy approach used in cross-cultural studies. Respondents were 906 health workers (men = 56%; caregivers 60%). They responded to a bilingual version of RSES. We... -
Grazing management that regenerates ecosystem function and grazingland livelihoods
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Richard Teague --- Department of Ecosystem Science and Management, USA Matt Barnes --- Shining Horizons Land Management LLC, USAAdopting a systems view and regenerative philosophy can indicate how to regenerate ecosystem function on commercial-scale agro-ecological landscapes. Adaptive multi-paddock grazing management is an example of an approach for grazinglands. Leading conservation farmers have achieved superior results in ecosystem improvement,... -
Does Holistic Planned Grazing™ work on native rangelands?
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Heidi-Jayne Hawkins --- Department of Biological Sciences, South Africa Alan Short --- Themeda Eco Consulting, South Africa Kevin P Kirkman --- Grassland Science, South AfricaThe balance of papers in this Special Issue show that how Holistic Planned Grazing™ is managed and where it is used impacts the efficacy of the approach. While we will do well to develop more mechanistic models that can identify... -
Relationship between somatic growth and otolith growth: a case study of the ornate jobfish Pristipomoides argyrogrammicus from the coast of Réunion (SW Indian Ocean)
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: K Mahé --- Ifremer, Fisheries Laboratory, Sclerochronology Centre, France Y Aumond --- Ifremer, Le Port, France K Rabhi --- Ifremer, Fisheries Laboratory, Sclerochronology Centre, France R Elleboode --- Ifremer, Fisheries Laboratory, Sclerochronology Centre, France E Bellamy --- Ifremer, Laboratoire Environnement Ressources Languedoc Roussillon, France J Huet --- Ifremer, Le Port, France M Gault --- FRS Marine Laboratory, Scotland D Roos --- Ifremer, Le Port, FranceThe ornate jobfish Pristipomoides argyrogrammicus Valenciennes 1832 occurs in the Indo-West Pacific Ocean, where it is harvested by small-scale coastal fisheries. Management of this species is hindered by lack of adequate biological data. We sampled a total of 113 individuals... -
Interrogating patient-centredness in undergraduate medical education using an integrated behaviour model
Item type: Journal Article • Journal: South African Family Practice • Authors: E Archer --- Centre for Health Professions Education, South Africa EM Bitzer --- Centre for Higher and Adult Education, South Africa BB van Heerden --- Faculty of Medicine and Health Sciences, South AfricaBackground: Patient-centredness, an approach that puts the patient at the centre of the consultation, thus focusing on patients instead of on his/her diseases, has been identified by most medical schools as a desired core competence of their graduates. Despite some... -
Constrained relationship agency as the risk factor for intimate partner violence in different models of transactional sex
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Rebecca Fielding-Miller --- Department of Medicine, USA Kristin Dunkle --- South African Medical Research Council, South AfricaWomen who engage in transactional sex are more likely to experience intimate partner violence (IPV) and are at higher risk of HIV. However, women engage in transactional sex for a variety of reasons and the precise mechanism linking transactional sex... -
Determinants of forage adoption and production niches among smallholder farmers in Kenya
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Donald MG Njarui --- Kenya Agricultural and Livestock Research Organization-Katumani, Kenya Mwangi Gatheru --- Kenya Agricultural and Livestock Research Organization-Katumani, Kenya Elias M Gichangi --- Kenya Agricultural and Livestock Research Organization-Katumani, Kenya Elikana M Nyambati --- Kenya Agricultural and Livestock Research Organization-Headquarters, Kenya Clotilda N Ondiko --- Kenya Agricultural and Livestock Research Organization-Mtwapa, Kenya Keziah W Ndungu-Magiroi --- Kenya Agricultural and Livestock Research Organization-Kitale, KenyaA study was conducted to assess factors that influence adoption of forages and choice of production niches in smallholder farms in Kenya. A total of 786 farmers (268 from coastal lowlands, 171 from eastern midlands, 132 from central highlands and... -
Modelling the impacts of semi-intensive aquaculture on the foodweb functioning of a Nile Delta coastal lake
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Bocci --- Department of Environmental Sciences, Informatics and Statistics, Italy R Pastres --- Department of Environmental Sciences, Informatics and Statistics, Italy S Kholeif --- National Institute of Oceanography and Fisheries (NIOF), Egypt D Dalla Barba --- Department of Environmental Sciences, Informatics and Statistics, Italy D Brigolin --- Department of Environmental Sciences, Informatics and Statistics, ItalyNutrient loadings are an important component of aquaculture impacts as they can lead to cascade effects at the ecosystem level. An evaluation of these effects on foodweb functioning is presented and discussed for the case study of Lake Burullus in... -
Geostatistical modelling of the spatial life history of post-larval deepwater hake Merluccius paradoxus in the Benguela Current Large Marine Ecosystem
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Jansen --- Benguela Current Commission, Namibia K Kristensen --- Technical University of Denmark – National Institute of Aquatic Resources (DTU Aqua), Denmark TP Fairweather --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries (DAFF), South Africa P Kainge --- Ministry of Fisheries and Marine Resources (MFMR), Namibia JN Kathena --- Ministry of Fisheries and Marine Resources (MFMR), Namibia MD Durholtz --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries (DAFF), South Africa JE Beyer --- Technical University of Denmark – National Institute of Aquatic Resources (DTU Aqua), Denmark UH Thygesen --- Technical University of Denmark – National Institute of Aquatic Resources (DTU Aqua), DenmarkOptimal and sustainable management of fish resources cannot be ensured without a thorough understanding of the migration patterns and population (demographic stock) structure. Recent studies suggest that these aspects of the economically and ecologically important deepwater hake Merluccius paradoxus are... -
Functionally graded metal matrix composite by centrifugal casting technique mathematical correlation
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Williams S. Ebhota --- Discipline of Mechanical Engineering, South Africa Freddie L. Inambao --- Discipline of Mechanical Engineering, South AfricaThe functionally graded materials (FGMs) solidification process has complicated movement phenomena of fluid, solute and heat. These phenomena control the segregation of particles in a molten matrix, interactions of particles with a solidification front and the integration of particles in... -
Adoption of agrochemical management practices among smallholder cocoa farmers in Ghana
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Gideon Danso-Abbeam --- SAEES – Discipline of Agricultural Economics, South Africa Lloyd J. S. Baiyegunhi --- SAEES – Discipline of Agricultural Economics, South AfricaThis study explores smallholder cocoa farmers’ adoption decisions of agrochemical inputs in the Ghanaian cocoa industry using farm-level data collected from a sample of 838 farm households in four cocoa producing regions. Multivariate probit and Tobit models were used to... -
Freshwater crayfish invasions in South Africa: past, present and potential future
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: AL Nunes --- Centre for Invasion Biology, Department of Botany and Zoology, South Africa TA Zengeya --- Centre for Invasion Biology, South Africa GJ Measey --- Centre for Invasion Biology, Department of Botany and Zoology, South Africa OLF Weyl --- Centre for Invasion Biology, South AfricaFreshwater crayfish invasions have been studied around the world, but less so in Africa, a continent devoid of native freshwater crayfish. The present study reviews historical and current information on alien freshwater crayfish species introduced into South Africa and aims... -
Seasonal habitat requirements of Lemon Dove (Aplopelia larvata) in coastal forest: camera-trap surveys of a reclusive species
Item type: Journal Article • Journal: African Zoology • Authors: David A Ehlers Smith --- School of Life Sciences, South Africa Yvette C Ehlers Smith --- School of Life Sciences, South Africa Colleen T Downs --- School of Life Sciences, South AfricaThe modification of natural habitats requires behavioural plasticity, which may be challenging for ‘specialist’ species. Quantifying habitat requirements and behavioural responses of specialists to landscape transformation is thus a priority for baseline data to inform conservation practices. Using camera-trap surveys... -
Age and growth of narrow-barred Spanish mackerel Scomberomorus commerson in the coastal waters of southern Mozambique and KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: B Lee --- Oceanographic Research Institute (ORI), South Africa BQ Mann --- Oceanographic Research Institute (ORI), South AfricaThe narrow-barred Spanish mackerel Scomberomorus commerson is one of the most important linefish species caught in KwaZulu-Natal and southern Mozambique waters, forming the basis of important commercial, artisanal and recreational fisheries. A total of 439 S. commerson were sampled along... -
Volume estimation of Cryptomeria japonica logs in southern Brazil using artificial intelligence models
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Carlos R Sanquetta --- Forest Sciences Department, Brazil Luani RO Piva --- Postgraduate Program on Tropical Forests Sciences, Brazil Jaime Wojciechowski --- Professional and Technological Education Sector, Brazil Ana PD Corte --- Forest Sciences Department, Brazil Ana B Schikowski --- Forest Sciences Department, BrazilThis study aimed to test taper functions and artificial intelligence (AI) models in order to estimate merchantable volumes of Japanese cedar (Cryptomeria japonica) trees in a homogenous plantation in southern Brazil. A total of 30 individuals were rigorously scaled and... -
Modelling machinery procurement with an emphasis on engineering features
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Basil Olufemi Akinnuli --- Department of Industrial and Production Engineering, NigeriaEngineering features are one of the predominant factors in considering machines for procurement; others are economic and supply conditions. Three major attributes considered under these strategic decisions are engineering features (reliability), economic features (annual operating cost) and supply condition (delivery... -
Household wealth and adoption of Integrated Striga Management (ISM) technologies in northern Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: L. J. S. Baiyegunhi --- School of Agricultural, Earth and Environmental Sciences, Discipline of Agricultural Economics, South Africa M. B. Hassan --- School of Agricultural, Earth and Environmental Sciences, Discipline of Agricultural Economics, South AfricaAgricultural households in developing countries often are unable and unwilling to adopt new technologies due to the deterrents to adoption imposed by numerous socio-economic, institutional and ecological factors. However, economic theory predicts that relatively wealthy households have better ability to... -
Modelling of an on-farm direct expansion bulk milk cooler to establish baseline energy consumption without milk pre-cooling: A case of Fort Hare Dairy Trust, South Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Russel Mhundwa --- Fort Hare Institute of Technology, South Africa Michael Simon --- Fort Hare Institute of Technology, South Africa Stephen Loh Tangwe --- Fort Hare Institute of Technology, South AfricaStorage of milk at a low temperature of 4°C inhibits bacterial growth. As such bulk milk coolers (BMC) are used for cooling and storage of milk on dairy farms. This paper presents performance monitoring of a direct expansion bulk milk... -
An evaluation of personality traits associated with job satisfaction among South African anaesthetists using the Big Five Inventory
Item type: Journal Article • Journal: Southern African Journal of Anaesthesia and Analgesia • Authors: P Kisten --- Department of Anaesthesiology, South Africa H Kluyts --- Department of Anaesthesiology, South AfricaBackground: Job satisfaction is a vital contributor to occupational well-being and may be instrumental in mitigating stress and the adverse effects thereof. This is particularly pertinent in anaesthesiology, which is an inherently stressful field. There are myriad factors, including personality... -
Psychometric validation of an Organisational Performance Questionnaire (OPQ) based on the Burke-Litwin model
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Benny Olivier --- University of South Africa, South AfricaThis study reports the findings on the development and validation of an Organisational Performance Questionnaire (OPQ) based on the Burke-Litwin model. Respondents were 398 employees from various public and private sector organisations in South Africa, consisting of different genders (male... -
Pathways to violence propensity: Results from a two-wave study of young males in urban South Africa
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Ian Edelstein --- Human Sciences Research Council, South AfricaThe aim of this study was to model pathways to violence propensity and violent behaviour among boys and young men in a high-violence community in South Africa. To that end, 284 young males (11 to 23 years old) from Khayelitsha,... -
Authentic leadership, followership, and psychological capital as antecedents of work engagement
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Marieta du Plessis --- Department of Industrial Psychology, South Africa Adré B. Boshoff --- Department of Industrial Psychology, South AfricaThe present study investigated authentic leadership, psychological capital, and followership behaviour influences on work engagement of employees. Respondents were 901 South African employees within the healthcare industry organisation (n = 647) and mining industry (n = 254). The employees completed... -
Survival estimates for the greater crested tern Thalasseus bergii in southern Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Payo-Payo --- Group of Ecology and Animal Demography (GEDA), Spain A Sanz-Aguilar --- Group of Ecology and Animal Demography (GEDA), Spain D Gaglio --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa RB Sherley --- Environment and Sustainability Institute, University of Exeter, United Kingdom TR Cook --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa R Altwegg --- Statistics in Ecology, Environment and Conservation, Department of Statistical Sciences, and African Climate and Development Initiative, South Africa PG Ryan --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South AfricaThe nominate race of the greater crested tern Thalasseus bergii breeds only along the coast of the Benguela region (west coast) of southern Africa, where its population is increasing, in contrast to other species of breeding seabirds in the region... -
Evaluating maize yield variability and gaps in two agroecologies in northern Ghana using a crop simulation model
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Dilys S MacCarthy --- Soil and Irrigation Research Centre, School of Agriculture, College of Basic and Applied Sciences, Ghana Samuel G Adiku --- Department of Soil Science, School of Agriculture, College of Basic and Applied Sciences, Ghana Bright S Freduah --- Soil and Irrigation Research Centre, School of Agriculture, College of Basic and Applied Sciences, Ghana Alpha Y Kamara --- International Institute of Tropical Agriculture, Nigeria Stephen Narh --- Soil and Irrigation Research Centre, School of Agriculture, College of Basic and Applied Sciences, Ghana Alhassan L Abdulai --- Savanna Agricultural Research Institute, GhanaThe yield gap and variability in maize under smallholder systems in two agroecologies in northern Ghana were evaluated using a decision support system for agrotechnology transfer (DSSAT). The model was used to assess (1) the potential yield of maize (YPOT),... -
Assessment of noise-levels of generator-sets in seven cities of South-Southern Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Osagie Ibhadode --- Building Research Department, Nigeria I. T. Tenebe --- Department of Civil Engineering, Nigeria P. C. Emenike --- Department of Civil Engineering, Nigeria O. S. Adesina --- Dept. of Mathematical Science, Nigeria A. F. Okougha --- Science Laboratory Technology Research Department, Nigeria F. O. Aitanke --- Department of Production Engineering, NigeriaNoise pollution has been shown to be a global health hazard and this could be aggravated by the use of noise-emitting generators. Therefore, this study aims to determine the Sound Pressure Levels Sound Power Levels as well as Noisiness of... -
Phytomass estimation using eMODIS NDVI and ground data in arid rangelands of Morocco
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Hamid Mahyou --- Centre Régional de la Recherche Agronomique d’Oujda, Morocco Bernard Tychon --- Department of Environmental Sciences and Management, Belgium Marie Lang --- Department of Environmental Sciences and Management, Belgium Riad Balaghi --- Centre Régional de la Recherche Agronomique de Meknès, MoroccoThe assessment of rangeland productivity in semi-extensively grazed arid rangelands is a prerequisite for livestock management in relation to sustainable use of pastoral resources. The objective of this study was to assess rangeland productivity based on normalised difference vegetation index... -
Temperature control of the distributional range of five C3 grass species in the uKhahlamba-Drakensberg Park, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Luke K Bentley --- South African Environmental Observation Network, South Africa Tim G O’Connor --- South African Environmental Observation Network, South AfricaGlobal climate change is expected to influence the distribution of global biodiversity. C4 and C3 perennial grasses co-occur in the fire-prone KwaZulu-Natal uKhahlamba-Drakensberg grasslands, with C3 grass species occurring at cooler locations in the mountain range and C4 grass species... -
Simultaneous selection for multiple traits in sugarcane breeding populations using logistic regression models
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Marvellous Zhou --- South African Sugarcane Research Institute, South AfricaSimultaneous selection for multiple traits in plant breeding increases the value of cultivars to growers. Visual selection is inefficient while multivariate statistical analysis is too complicated for early stages. The objective of this study was to demonstrate logistic regression models... -
Did informed order flow move to multilateral trading facilities? Evidence for some Eurozone countries
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Paulo Pereira da Silva --- CEFAGE, Universidade de Évora, PortugalThis paper investigates the effects of the fragmentation of European stock markets after MiFID application in 2007. Specifically, we discuss whether the process of fragmentation elicited a flight of informed trading from the primary stock exchanges to the incoming multilateral... -
International transmission of risk factor movements: The case of developed markets
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Hyung-Suk Choi --- School of Business, Korea Doojin Ryu --- College of Economics, Korea Heejin Yang --- School of Finance, KoreaUnder the Carhart four-factor system, this study examines the international transmission mechanism among country-specific risk factors by focusing on the cross-border transmission of factor innovation. We find that international stock markets are interrelated with respect to market, size, value and... -
Confirming the structure of the dual process model of diversity amongst public sector South African employees
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Leon T. B. Jackson --- WorkWell Research Unit for Economics and Management Sciences, South Africa Fons J. R. van de Vijver --- WorkWell Research Unit for Economics and Management Sciences, South AfricaWe set out to validate the structure of the Dual Process Model of Workplace Diversity in a South African work setting contrasting black and white African employees. The study participants were a convenience sample of 296 public service employees (black... -
Sharks caught in the KwaZulu-Natal bather protection programme, South Africa. 14. The smooth hammerhead shark Sphyrna zygaena (Linnaeus)
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: ML Dicken --- KwaZulu-Natal Sharks Board, South Africa H Winker --- Branch: Fisheries Management, Department of Agriculture, South Africa MJ Smale --- Port Elizabeth Museum, South Africa G Cliff --- KwaZulu-Natal Sharks Board, South AfricaThe current study provides long-term catch-rate, biological and feeding data for smooth hammerhead sharks, Sphyrna zygaena, caught in South Africa’s KwaZulu-Natal bather protection programme. In total, 2 512 S. zygaena were caught in net installations between 1978 and 2014, and... -
The age and growth of hottentot seabream Pachymetopon blochii before and after the South African linefish state of emergency in 2000
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MW Farthing --- Department of Ichthyology and Fisheries Science, South Africa AC Winkler --- Department of Ichthyology and Fisheries Science, South Africa K Anderson --- Department of Ichthyology and Fisheries Science, South Africa S Kerwath --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries (DAFF), South Africa C Wilke --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries (DAFF), South Africa WM Potts --- Department of Ichthyology and Fisheries Science, South AfricaThe hottentot seabream Pachymetopon blochii is a small-sized (maximum 2.67 kg) sparid endemic to southern Africa. It is an important target in South Africa's Western Cape traditional linefishery, particularly in the absence of more valuable pelagic species (such as Thyrsites... -
Population abundance and seasonal migration patterns indicated by commercial catch-per-unit-effort of hakes (Merluccius capensis and
M. paradoxus ) in the northern Benguela Current Large Marine Ecosystem Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JN Kathena --- National Marine Information and Research Centre (NatMIRC), Ministry of Fisheries and Marine Resources, Namibia D Yemane --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries (DAFF), South Africa N Bahamon --- Centre d’Estudis Avançats de Blanes (CEAB – CSIC), Spain T Jansen --- National Institute of Aquatic Resources (DTU Aqua), DenmarkWe developed generalised additive models (GAMs) to estimate standardised time-series of population abundance indices for assessment purposes and to infer ecological and behavioural information on northern Benguela hakes, Merluccius capensis and M. paradoxus, using haul-by-haul commercial trawl catch-rate data as... -
Networking dimensions and performance of event management ventures in Kenya
Item type: Journal Article • Journal: Research in Hospitality Management • Authors: Jacqueline Cheptepkeny Korir --- School of Tourism Hospitality and Events Management, KenyaThe role of networking in the sharing of knowledge and information is well documented. What is not clear, however, are the facets of networks that best drive firm performance, and whether or not the nature of business is a factor... -
Health-related subjective well-being with emetophobia
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Anuscha Liebenberg --- Department of Psychology, South Africa Monika dos Santos --- Department of Psychology, South AfricaThis study explored subjective well-being among white females with emetophobia disorder (n = 20, married = 50%, age range 20–25). The participants completed self-report measures of gastrointestinal symptoms, as well as the Gastrointestinal Symptom Severity Index and Gastrointestinal Symptoms-Related Subjective... -
Predictive modelling of the potential future distribution of Vachellia nilotica within the KwaZulu-Natal province of South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Janet Taylor --- Natural Resources Section, KwaZulu-Natal Department of Agriculture and Rural Development, South Africa Nico Smit --- Department of Animal, Wildlife and Grassland Sciences, South Africa Debbie Jewitt --- Biodiversity Research and Assessment, Ezemvelo KZN Wildlife, South AfricaMany regions of South Africa are prone to woody plant thickening. This can have an ecologically detrimental effect on the open savannas and grasslands. KwaZulu-Natal, a province on the east coast of South Africa, is currently experiencing an increase in... -
Data-moderate assessments of Cape monkfish Lophius vomerinus and west coast sole Austroglossus microlepis in Namibian waters
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JN Kathena --- National Marine Information and Research Centre (NatMIRC), Ministry of Fisheries and Marine Resources (MFMR), Namibia A Kokkalis --- National Institute of Aquatic Resources (DTU Aqua), Denmark MW Pedersen --- National Institute of Aquatic Resources (DTU Aqua), Denmark JE Beyer --- National Institute of Aquatic Resources (DTU Aqua), Denmark UH Thygesen --- National Institute of Aquatic Resources (DTU Aqua), DenmarkThere is global interest in providing scientific advice on optimal harvesting of all commercially exploited fish stocks. Nevertheless, many commercially important stocks lack analytical assessments. Therefore, we evaluate a data-moderate stock assessment method: the stochastic surplus production model in continuous... -
Structure and Management of Formal and Informal Business Activities in Entrepreneurial Family and Small Firms in Africa
Item type: Journal Article • Journal: Africa Journal of Management • Authors: Moses N. Kiggundu --- Sprott School of Business, Carleton University, Canada Siva P. Pal --- Sprott School of Business, Carleton University, CanadaThis article focuses on the meso-micro levels of entrepreneurial family-owned and small firms operating in Africa’s informal economy. It examines how these firms manage formal and informal business activities, and how entrepreneurs manage business risks associated with market imperfections. After... -
Whole-tree sap flow responses to soil water and weather variables for Pinus radiata and three indigenous species in a southern afrotemperate forest region
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Tatenda Mapeto --- School of Natural Resources Management, Nelson Mandela University, George Campus, South Africa Josua Louw --- School of Natural Resources Management, Nelson Mandela University, George Campus, South Africa Mark Gush --- Council for Scientific and Industrial Research, South Africa Jeanette Pauw --- School of Natural Resources Management, Nelson Mandela University, George Campus, South AfricaIn a water-scarce country such as South Africa, timber and fibre production often stands in conflict with catchment water yields. The optimal provision of both is sought. Forest hydrological experiments improve our understanding of the soil–plant–atmosphere continuum and facilitate the... -
The determinants of farmers’ decision to produce African leafy vegetables in the Limpopo province, South Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Grany M. Senyolo --- Department of Crop Sciences, South Africa Edilegnaw Wale --- School of Agriculture, Earth and Environmental Sciences, Discipline of Agricultural Economics, South Africa Gerald F. Ortmann --- School of Agriculture, Earth and Environmental Sciences, Discipline of Agricultural Economics, South AfricaThere is a decline in the production, utilization and diversity of underutilized crops including African Leafy Vegetables (ALVs), which poses a threat to the status of food security and rural development. This study examines the factors influencing households’ participation decision... -
Personality and work-home interaction among dual-earner couples in South Africa: Testing an actor-partner interdependence model
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Carin Hill --- Department of Industrial Psychology and People Management, South Africa Lynne Blunn --- Department of Industrial Psychology and People Management, South AfricaThis study aimed to investigate the effect of personality on work-home interaction crossover effects among dual-earner couples in South Africa. The participants were dual-earner couples (n = 264; 132 couples) with young children. They completed measures on work-home interaction and... -
A conceptual model of heritage dimensions and agrotourism: Perspective of Nandi County in Kenya
Item type: Journal Article • Journal: Research in Hospitality Management • Authors: Belsoy Josphat Sawe --- Departmentof Hotel and Hospitality Management, School of Tourism Hospitality and Events Management, Kenya Damiannah Kieti --- Departmentof Hotel and Hospitality Management, School of Tourism Hospitality and Events Management, Kenya Bob Wishitemi --- Departmentof Hotel and Hospitality Management, School of Tourism Hospitality and Events Management, KenyaConceptual frameworks have previously been used to give a structure to research that essentially simplifies thinking and clarifies issues, while at the same time providing a common reference point. Agrotourism is fast emerging as a key player in the activation... -
Population fluctuations of Cerithidea decollata (Gastropoda: Potamididae) in mangrove habitats of the St Lucia Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JL Raw --- , South Africa GM Rishworth --- , South Africa R Perissinotto --- , South Africa JB Adams --- , South AfricaMangrove macrobenthos species are used as ecological indicators as they are sensitive to changes in sediment properties. In this study, the population density of the common mangrove whelk Cerithidea decollata was assessed during different environmental conditions in the St Lucia... -
The autumn occurrence and spatial distribution of cetaceans in the waters of Mauritania during a geophysical survey in 2012
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: G Russell --- , United Kingdom A Sánchez-Cabanes --- , United Kingdom M Nimak-Wood --- , United KingdomThis study aimed to identify the occurrence and spatial distribution of cetaceans in Mauritanian waters (eastern Atlantic). A geophysical survey was conducted over 92 days between September and December 2012. Over 967 km was surveyed, with 1 017 h of... -
Extreme significant wave height climate in the Gulf of Guinea
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AA Osinowo --- , Nigeria EC Okogbue --- , Nigeria EO Eresanya --- , Nigeria OS Akande --- , NigeriaThis article investigates spatio-temporal trends for different return periods of extreme significant wave height (SWH) in the Gulf of Guinea (GG), northeastern tropical Atlantic Ocean, based on a 37-year (1980–2016) wave hindcast. High-resolution reanalysis windfield datasets were used to force... -
Distribution and habitat use of Indo-Pacific bottlenose dolphins Tursiops aduncus along the south coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: OA Vargas-Fonseca --- , South Africa SP Kirkman --- , South Africa D Conry --- , South Africa GM Rishworth --- , South Africa V Cockcroft --- , South Africa PA Pistorius --- , South AfricaThe distribution and habitat use of the Indo-Pacific bottlenose dolphin Tursiops aduncus along the south coast of South Africa was investigated using bi-monthly boat-based surveys, from 2013 to 2016, over a distance of 145 km between the Goukamma and Tsitsikamma... -
The presence of artificial water points structures an arid-zone avian community over small spatial scales
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Salamatu Abdu --- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa Alan TK Lee --- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa Susan J Cunningham --- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South AfricaWater plays a key role in avian thermoregulation, especially when environmental temperatures approach or exceed body temperature. Birds living in arid environments need to either be adapted to life with unreliable access to water, or engage in large-scale movements to... -
Effects of temporal factors, nesting microhabitat and nest position on the survival of passerine nests in a Tunisian oasis habitat
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Jihen Boukhriss --- Unité de recherche «Ecologie de la faune terrestre» (UR17ES44), Faculté des Sciences de Gabès, Tunisia Slaheddine Selmi --- Département des Sciences de la Vie, Faculté des Sciences de Gabès, TunisiaIdentifying the ecological factors shaping bird nest survival is essential for understanding bird population dynamics, as well as for conservation purposes. Using data obtained by monitoring natural bird nests in one oasis in south-eastern Tunisia, we fitted logistic exposure models... -
Development and validation of a stem volume equation for Cupressus lusitanica in Gergeda Forest, Ethiopia
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Mengesha Tsega --- College of Environmental Science and Engineering, China Awoke Guadie --- Department of Biology, College of Natural Sciences, Ethiopia Zebene Lakew Teffera --- College of Environmental Science and Engineering, China Yigez Belayneh --- College of Environmental Science and Engineering, China Dongjie Niu --- State Key Laboratory of Pollution Control and Resource Reuse, ChinaStem volume equations were fitted for Cupressus lusitanica in Gergeda Forest, Ethiopia using six different established equation forms. A total of 260 trees were measured for their diameter at breast height (D), total height (H )and stem volume using destructive sampling... -
Time-dependent volatility in futures contract options
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Jilong Chen --- International Business School, School of Finance, China Christian Ewald --- University of Glasgow, UK Ali M. Kutan --- Business School, Department of Economics and Finance, USAThe Schwartz (1997) two-factor model is the benchmark model for pricing futures options, and the volatility is constant, which is similar to the Black-Scholes model. In this paper, we use a similar method which can make the Black-Scholes model be... -
Dominant factors for energy choice decisions by households in Tanzania: A case study of selected villages in Mvomero District
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Felichesmi Selestine Lyakurwa --- Faculty of Science and Technology, Eliaza Mkuna --- Faculty of Social Sciences,Household choice of energy sources for various social-economic activities has been associated with improved community livelihood and ecosystem quality. In this study, the multinomial probit model (MNP) was employed to establish the dominant factors for energy choice decisions by households... -
Abundance estimates of an isolated population of common bottlenose dolphins Tursiops truncatus in Walvis Bay, Namibia, 2008–2012
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SH Elwen --- Mammal Research Institute, University of Pretoria, South Africa RH Leeney --- Natural History Museum, United Kingdoms T Gridley --- Centre for Statistics in Ecology, Environment and Conservation, Department of Statistical Sciences,The coastal population of common bottlenose dolphins Tursiops truncatus found in Namibia is regionally isolated and unique. This population faces several potential anthropogenic threats, especially in Walvis Bay, including boat-based tourism, a commercial harbour undergoing expansion, and aquaculture for oysters... -
Spatial considerations when monitoring reef fishes
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: D Parker --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries (DAFF), South Africa H Winker --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries (DAFF), South Africa ATF Bernard --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa MKS Smith --- South African National Parks, Rondevlei Scientific Services, South Africa A Götz --- South African Environmental Observation Network (SAEON), South AfricaSpatial dependence can obscure relationships between response and explanatory variables because of structuring within the residuals reducing variance and biasing coefficient estimates. Here, we highlight the influence of the spatial component, in the presence of spatial dependence, on abundance trends... -
Modelling expected trout ranges under current and future water temperature regimes in the Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NA Rivers-Moore --- Centre for Water Resources Research, South Africa BR Ellender --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa OLF Weyl --- Center for Invasion Biology, SAIAB, South AfricaDifferent values have resulted in conflicts between anglers and conservation lobbies in the management of trout in South Africa. Key to the conflict is the demarcation of boundaries to areas in which brown trout Salmo trutta and rainbow trout Oncorhynchus... -
Developing a taper model for the Pinus elliottii × P. caribaea var. hondurensis hybrid in South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Madeleen Algera --- Planning Department, Komatiland Forest, South Africa Christoph Kätsch --- Postgraduate Forest Programme, South Africa Paxie W Chirwa --- Postgraduate Forest Programme, South AfricaA relatively new hybrid, Pinus elliottii × P. caribaea var. hondurensis (Pexc), for which a taper model does not exist, is being planted commercially in South Africa. This study primarily focused on developing a taper model for Pexc in South... -
Mixed-effect non-linear modelling for diameter estimation along the stem of Tectona grandis in mid-western Brazil
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Luciano Rodrigo Lanssanova --- Postgraduate Program of Forestry Sciences, Department of Forest Engineering, Brazil Sebastião do Amaral Machado --- Postgraduate Program of Forestry Engineering, Department of Forest Engineering, Brazil Alexandre Techy de Almeida Garrett --- Postgraduate Program of Forestry Sciences, Department of Forest Engineering, Brazil Izabel Passos Bonete --- Postgraduate Program of Forestry Sciences, Department of Forest Engineering, Brazil Allan Libanio Pelissari --- Postgraduate Program of Forestry Engineering, Department of Forest Engineering, Brazil Afonso Figueiredo Filho --- Postgraduate Program of Forestry Sciences, Department of Forest Engineering, Brazil Franciele Alba da Silva --- Postgraduate Program of Forestry Engineering, Department of Forest Engineering, Brazil Lucas Dalmolin Ciarnoschi --- Postgraduate Program of Forestry Engineering, Department of Forest Engineering, BrazilThis study evaluated the efficiency of taper functions and the application of mixed-effect modelling for diameter estimation along the stems of Tectona grandis. We sampled 266 trees of Tectona grandis, measuring the diameter at relative heights for volume determination, grouping... -
Design, construction and mathematical modelling of the performance of a biogas digester for a family in the Eastern Cape province, South Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Patrick Mukumba --- Department of Physics, South Africa Golden Makaka --- Department of Physics, South Africa Sampson Mamphweli --- Department of Physics, South Africa Peace-maker Masukume --- Department of Physics, South AfricaCurrently, South Africa is experiencing electricity blackouts as result of an energy shortage. Biogas can be a solution to South Africa’s energy needs, especially in the rural areas of the Eastern Cape province that have plenty of biogas substrates from... -
Mathematical model showing how socioeconomic dynamics in African cities could widen or reduce inequality
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Obiora Cornelius Collins --- Institute of Systems Science, South Africa Thokozani Silas Simelane --- Institute of Systems Science, South Africa Kevin Jan Duffy --- Institute of Systems Science, South AfricaCities are important forces of national socioeconomic development. Individuals in cities often belong to different socioeconomic statuses depending on their levels of income, education and nature of occupation. Income, employment and education opportunities are among the main attractions of most... -
Effect of multiple intervention models on uptake of HIV testing services and sexual behaviour among residents of military cantonments in south-east Nigeria
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Benedict N Azuogu --- Department of Community Medicine, Nigeria Lawrence U Ogbonnaya --- Department of Community Medicine, Nigeria Chukwuma D Umeokonkwo --- Department of Community Medicine, Nigeria Chihurumnanya Alo --- Department of Community Medicine, Nigeria Ngozi A Ifebunandu --- Department of Internal Medicine, Nigeria Christopher N Obionu --- Department of Community Medicine, Nigeria Adaoha P Agu --- Department of Community Medicine, Nigeria Victoria C Azuogu --- Department of Health Education, Nigeria Felix O-O Oyari --- Department of Community Medicine, Nigeria Ijeoma N Okedo-Alex --- Department of Community Medicine, Nigeria Ifenyinwa M Okafor --- Department of Community Medicine, Nigeria Ugochukwu C Madubueze --- Department of Community Medicine, NigeriaBackground: HIV testing and counselling (HTC) has been a viable tool in controlling the spread of HIV/AIDS, and serves as the entry point in the HIV care and treatment cascade. In Africa, HIV-related morbidity and mortality are high with thousands... -
Seasonal cycle of the salinity barrier layer revealed in the northeastern Gulf of Guinea
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AN Dossa --- International Chair in Mathematical Physics and Applications (ICPMA-UNESCO Chair), Benin CY Da-Allada --- International Chair in Mathematical Physics and Applications (ICPMA-UNESCO Chair), Benin G Herbert --- Institut de Recherche pour le Développement (IRD), Instrumentation, Moyens Analytiques, France B Bourlès --- Institut de Recherche pour le Développement (IRD), Instrumentation, Moyens Analytiques, FranceThe region located in the far northeast of the Gulf of Guinea (NEGG), eastern tropical Atlantic, remains poorly documented due to a lack of available in situ ocean data. Heavy rainfall and intense river discharges observed in this region induce... -
Factors affecting the choice of marketing outlet selection strategies by smallholder farmers in Swaziland
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Bongiwe Porrie Dlamini-Mazibuko --- Discipline of Agricultural Economics, South Africa Stuart Ferrer --- Discipline of Agricultural Economics, South Africa Gerald Ortmann --- Discipline of Agricultural Economics, South AfricaThis paper explores smallholder vegetable farmers’ marketing channel selection decisions using data collected from a sample of 140 farmers from Manzini and Hhohho regions of Swaziland. Multivariate probit analysis was applied to examine the determinants of marketing channels participation. The... -
Designing a business model from process perspective
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Aygül Dönmez-Turan --- Faculty of Economic and Administrative Sciences, Departments of Business Administration, Turkey Mina Özevren --- Faculty of Business Administration, TurkeyThe business model is a relatively new concept in entrepreneurship and strategic management literature. Thus, the growing body of business model literature contains qualitative research, especially case studies. The key reason business models are explained via case studies is that... -
Oil price thresholds and stock returns
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: An-Sing Chen --- Department of Finance, Taiwan, R.O.C. Che-Ming Yang --- Department of Finance, Taiwan, R.O.C.In this article, we apply the threshold autoregressive model to examine oil price thresholds and the relationship between oil prices and the returns of 25 benchmark portfolios formed on size and book-to-market. Our results show that the relationship between the... -
The Fama-French five-factor model: Evidence from the Johannesburg Stock Exchange
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Shaun Cox --- School of Economic & Business Sciences, South Africa James Britten --- School of Economic & Business Sciences, South AfricaThis study tests the effectiveness of the Fama and French (2015) five-factor model in explaining returns on the Johannesburg Securities Exchange (JSE). The five-factor model is compared to the traditional Fama-French three-factor model as well as other factor combinations. The... -
Accessing HIV treatment and care services in fishing communities around Lake Victoria in Uganda: mobility and transport challenges
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Christopher Tumwine --- Centre for Social Research in Health, Australia Peter Aggleton --- Centre for Social Research in Health, Australia Stephen Bell --- Kirby Institute for Infection and Immunity in Society, AustraliaQualitative research exploring the influence of community-level factors on access to and use of HIV treatment and care services among people living in fishing communities is limited, especially with respect to those already in receipt of HIV care and on... -
Gender appropriateness of field days in knowledge generation and adoption of push-pull technology in eastern Africa
Item type: Journal Article • Journal: East African Agricultural and Forestry Journal • Authors: AW Murage --- Kenya Agricultural and Livestock Research Organization (KALRO), JO Pittchar --- International Centre of Insect Physiology and Ecology (ICIPE), Kenya CAO Midega --- International Centre of Insect Physiology and Ecology (ICIPE), Kenya CO Onyango --- Asian Vegetable Research and Development Centre (ADRDC), JA Pickett --- Rothamsted Research, United Kingdom ZR Khan --- International Centre of Insect Physiology and Ecology (ICIPE), KenyaAdoption studies have identified gender as one of the factors that determine technology uptake and this has been linked to women’s access to farming information or lack of it. Technology scaling up systems should utilise pathways that are compatible with... -
Linking empowering leadership and career calling: The mediating role of psychological need fulfilment
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Leigang Zhang --- School of Teacher Education, China Tingting Jin --- Intensive Care Unit, ChinaThis study investigated whether and how empowering leadership influences employees’ career calling by exploring the mediating role of psychological need fulfilment. Participants comprised a convenience sample of 584 clinical nurses from ten public hospitals in China (female = 85.2%; age... -
Towards the development of a community-based model for promoting cervical cancer prevention among Yoruba women in Ibadan Nigeria: application of PEN-3 model
Item type: Journal Article • Journal: Southern African Journal of Gynaecological Oncology • Authors: AD Olanlesi-Aliu --- School of Nursing, University of Western Cape, South Africa PD Martin --- School of Nursing, University of Western Cape, South Africa FM Daniels --- School of Nursing, University of Western Cape, South AfricaObjective: Through the identification of the barriers to the uptake of prevention services for cervical cancer and ways to promote prevention of cervical cancer in the community, this research study purposed the development of a community-based model for promoting cervical... -
HIV treatment support services in Tanzania: a cost and efficiency analysis at facility and community levels
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Steven Forsythe --- Avenir Health, United States of America Bryant Lee --- Palladium Group Inc., United States of America Kuki Tarimo --- Palladium Group Inc., United States of America Boniface Silvan --- Ministry of Health, Community Development, Gender, Elderly and Children, Tanzania Marianna Balampama --- Palladium Group Inc., United States of America Julie Chitty --- Palladium Group Inc., United States of America Sara Bowsky --- Palladium Group Inc., United States of AmericaDifferentiated service delivery models provide an opportunity to reduce the cost of HIV treatment while increasing the focus on advanced patients. Also, stable patients who need less attention can visit facilities less frequently, saving time and money and reducing overcrowding... -
Which delivery model innovations can support sustainable HIV treatment?
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Caroline A Bulstra --- Erasmus Medical Centre, Department of Public Health, The Netherlands Jan AC Hontelez --- Erasmus Medical Centre, Department of Public Health, The Netherlands Osondu Ogbuoji --- Center for Policy Impact in Global Health, USA Till Bärnighausen --- Institute of Global Health, University of Heidelberg, GermanyThe rapid scale-up of antiretroviral treatment (ART) for HIV since the mid-2000s, mostly through disease-specific or “vertical” programmes, has been a highly successful undertaking, which averted millions of deaths and prevented many new infections. However, the dynamics of the HIV... -
Profitability in Egyptian hotels: business model and sustainability impact
Item type: Journal Article • Journal: Research in Hospitality Management • Authors: Karam Zaki --- Hotel Studies Department, Faculty of Tourism and Hotels, Egypt Omar Qoura --- Hotel Studies Department, Faculty of Tourism and Hotels, EgyptThe goals of this research are: first, to identify factors impacting hotel profitability; second, to explore the profitability ratios most commonly used by Egyptian hotel managers; third, to examine whether the hotel profitability is considered an issue of control or... -
Point counts outperform line transects when sampling birds along routes in South African protected areas
Item type: Journal Article • Journal: African Zoology • Authors: Graeme S Cumming --- ARC Centre of Excellence for Coral Reef Studies, Australia Dominic AW Henry --- FitzPatrick Institute, South AfricaBird atlases have become an important source of distribution data for broad-scale analyses in ecology, biogeography and conservation. However, national bird atlases are undertaken in different ways in different countries, usually with little formal assessment of alternatives. Existing research suggests... -
Using mark-recapture methods to estimate population size and survival of pyjama sharks Poroderma africanum in Mossel Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SP Grusd --- Department of Biological Sciences and the Marine Research Institute, South Africa CL Moloney --- Department of Biological Sciences and the Marine Research Institute, South Africa G Distiller --- Statistics in Ecology, Environment and Conservation (SEEC), Department of Statistical Sciences, South Africa RGA Watson --- Oceans Research, South Africa PD Cowley --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa E Gennari --- Oceans Research, South AfricaThe pyjama shark Poroderma africanum (family Scyliorhinidae) is endemic to coastal waters of South Africa but its population characteristics are poorly known. This study aims to estimate baseline demographic parameters for P. africanum in Mossel Bay. We applied mark-recapture methods... -
Oxygen and temperature influence the distribution of deepwater Cape hake Merluccius paradoxus in the southern Benguela: a GAM analysis of a 10-year time-series
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: FL Mbatha --- Department of Biological Sciences and Marine Research Institute, South Africa D Yemane --- Department of Biological Sciences and Marine Research Institute, South Africa M Ostrowski --- Institute of Marine Research (IMR), Norway CL Moloney --- Department of Biological Sciences and Marine Research Institute, South Africa MR Lipiński --- Department of Ichthyology and Fisheries Science, South AfricaGeneralised additive models (GAMs) were applied to survey data to assess the influence of dissolved oxygen, water temperature and year of sampling upon the presence/absence of small (≤15 cm TL), medium (16–34 cm TL) and large (≥35 cm TL) size... -
The status and conservation of the Cape Gannet Morus capensis
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Richard B Sherley --- Environment and Sustainability Institute/Centre for Ecology and Conservation, United Kingdom Robert JM Crawford --- Department of Environment, Forestry and Fisheries (DEFF), South Africa Bruce M Dyer --- Department of Environment, Forestry and Fisheries (DEFF), South Africa Jessica Kemper --- African Penguin Conservation Project, Namibia Azwianewi B Makhado --- Department of Environment, Forestry and Fisheries (DEFF), South Africa Makhudu Masotla --- Department of Environment, Forestry and Fisheries (DEFF), South Africa Lorien Pichegru --- DST-NRF Centre of Excellence at the FitzPatrick Institute of African Ornithology, Department of Biological Sciences, South Africa Pierre A Pistorius --- DST-NRF Centre of Excellence at the FitzPatrick Institute of African Ornithology, Department of Biological Sciences, South Africa Jean-Paul Roux --- Ministry of Fisheries and Marine Resources, Namibia Peter G Ryan --- DST-NRF Centre of Excellence at the FitzPatrick Institute of African Ornithology, Department of Biological Sciences, South Africa Desmond Tom --- Ministry of Fisheries and Marine Resources, Namibia Leshia Upfold --- Department of Environment, Forestry and Fisheries (DEFF), South Africa Henning Winker --- Department of Environment, Forestry and Fisheries (DEFF), South AfricaThe Cape Gannet Morus capensis is one of several seabird species endemic to the Benguela upwelling ecosystem (BUS) but whose population has recently decreased, leading to an unfavourable IUCN Red List assessment. Application of ‘JARA’ (‘Just Another Red-List Assessment,’ a... -
Stock prices and dividends: A South African perspective
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Ailie Charteris --- Finance and Tax, South Africa Kudakwashe J. Chipunza --- Postgraduate student, Graduate School of Economic and Management Sciences, South AfricaThe present value model (PVM) is considered a cornerstone of financial theory and practice, yet the limited empirical tests thereof have produced varying results depending on the method used. In addition, these tests have focused principally on developed countries, with... -
Are macroeconomic factors adequate proxies for systematic influences in stock returns? A South African perspective
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Jan J. Szczygielski --- Department of Financial Management, Gauteng, South Africa Leon M. Brümmer --- Department of Financial Management, Gauteng, South Africa Hendrik P. Wolmarans --- Department of Financial Management, Gauteng, South Africa Adam Zaremba --- Dubai Business School, United Arab EmiratesWe investigate whether macroeconomic factors adequately proxy for systematic influences in stock returns within the South African context. We also investigate whether a commonly used solution to factor omission in macroeconomic factor models, the residual market factor, adequately reflects systematic... -
Self-esteem and psychological capital: Their mediation of the relationship between Big Five personality traits and creativity in college students
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Ming Hong --- Institute of Psychology, Belarus Dmitry G. Dyakov --- Institute of Psychology, Belarus Jianhong Zheng --- Department of Psychology, ChinaThis study examined self-esteem and psychological capital as a mediator of the relationship between Big Five personality traits and creativity. A convenience sample of 732 college students from Guangdong, Jiangsu, and Jiangxi provinces participated (females = 71.7%; mean age =... -
Using stable δ13C and δ15N isotopes to assess foodweb structures in an African subtropical temporary pool
Item type: Journal Article • Journal: African Zoology • Authors: L de Necker --- Water Research Group, Unit for Environmental Sciences and Management, South Africa A Manfrin --- Environmental Campus Birkenfeld, Germany Y Ikenaka --- Water Research Group, Unit for Environmental Sciences and Management, South Africa M Ishizuka --- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Japan L Brendonck --- Water Research Group, Unit for Environmental Sciences and Management, South Africa JHJ van Vuren --- Water Research Group, Unit for Environmental Sciences and Management, South Africa B Sures --- Department of Aquatic Ecology and Centre for Water and Environmental Research (ZWU), Germany V Wepener --- Water Research Group, Unit for Environmental Sciences and Management, South Africa NJ Smit --- Water Research Group, Unit for Environmental Sciences and Management, South AfricaSouthern Africa has one of the highest densities of temporary pools and some of the most understudied temporary wetlands in the world. Additionally, the eastern African annual killifishes (Nothobranchius spp.) are rare in southern Africa and found exclusively in temporary... -
Use of openly available occurrence data to generate biodiversity maps within the South African EEZ
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: D Yemane --- Department of Environment, Forestry and Fisheries (DEFF), South Africa SP Kirkman --- Department of Environment, Forestry and Fisheries (DEFF), South Africa T Samaai --- Department of Environment, Forestry and Fisheries (DEFF), South AfricaBiodiversity maps are an important component of ecosystem-based management and conservation. In the past, biodiversity maps were largely generated using patchy occurrence data from a range of data sources. Currently, substantial species occurrence data are readily available for large parts... -
Hydropedology in South Africa: Advances, applications and research opportunities
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Johan van Tol --- Department of Soil, Crop and Climate Sciences, South AfricaThe need to characterise and quantify hydrological processes in order to manage scarce water resources led to significant progress in the field of hydropedology in South Africa during the past decade. The adoption of hydropedological research by industry and government... -
Allometric relationships to predict aboveground biomass of 8–10-year-old Eucalyptus grandis × E. nitens in south-eastern Mpumalanga, South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: PB van Niekerk --- , South Africa DM Drew --- , South Africa SB Dovey --- , South Africa B du Toit --- , South AfricaSouth Africa is new to the implementation of climate change policies, and the forestry sector in this country is taking ownership of estimating its greenhouse gas inventories. Improving the level of accuracy of carbon stock estimations calls for the population... -
Fuelwood energy characteristics and biomass equations of the dominant species of northern Patagonian shrublands (Argentina)
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Matías G Goldenberg --- , Argentina Yamila A Cardoso --- , Argentina Facundo J Oddi --- , Argentina Lucas A Garibaldi --- , ArgentinaAlthough shrublands can be highly abundant, their bioenergy potential has barely been addressed. This is the case in northern Patagonian shrublands, where there is a lack of knowledge regarding biomass quantity and quality. The objective of this study was to... -
Genetic control of diameter and bark percentage in spotted gum (Corymbia spp.): can we breed eucalypts with more wood and less bark?
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: João Gabriel Zanon Paludeto --- , Brazil David Bush --- , Australia Regiane Abjaud Estopa --- , Brazil Evandro Vagner Tambarussi --- , BrazilThis study aimed to estimate the genetic parameters of diameter at breast height over bark (DBHOB), bark percentage (Bark%) and the correlation between DBHOB and Bark% for Corymbia spp. Three independent trials were evaluated during this study: C. variegata (CV)... -
Applying a social-ecological lens to opinions about HIV self-testing among Kenyan truckers who declined to test: a qualitative study
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Stephanie N Christian --- , USA Joanne E Mantell --- , USA Matthew L Romo --- , USA Christian Grov --- , USA Gavin George --- , South Africa Eva Mwai --- , Kenya Eston Nyaga --- , Kenya Jacob O Odhiambo --- , Kenya Kaymarlin Govender --- , South Africa Elizabeth A Kelvin --- , USAHIV prevalence among truckers in Africa is high and testing rates suboptimal. With numerous African countries having approved HIV self-testing kits, more information on how to design acceptable and accessible self-testing programs for high-risk populations is necessary. We explored views... -
Sustainable shellfish aquaculture in Saldanha Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Santa Marta --- , United Kingdom JG Ferreira --- , United Kingdom GC Pitcher --- , South Africa J Lencart e Silva --- , United KingdomThe carrying capacity for bivalve shellfish culture in Saldanha Bay, South Africa, was analysed through the application of the well-tested EcoWin ecological model, in order to simulate key ecosystem variables. The model was set up using: (i) oceanographic and water-quality... -
Spatial variation of nutrients and primary productivity in the Rufiji Delta mangroves, Tanzania
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Minu --- , Tanzania J Routh --- , Sweden JF Machiwa --- , Tanzania S Pamba --- , TanzaniaDeterminations of spatial and temporal variations in organic matter and nutrient dynamics in water and sediments are crucial for understanding changes in aquatic bodies. In this study, we (i) determine the spatial dynamics of dissolved inorganic nutrients, during the transition... -
Guidelines for promoting organisational resilience in South African schools
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Werner de Klerk --- , South Africa Jacob J.P. le Grange --- , South Africa Monique de Klerk --- , South Africa Jené Pretorius --- , South AfricaSustaining educator resilience is increasingly important in transitional societies which have a higher risk for dysfunction from coping with adjustments to emerging organisational practices with no local precedent. This would be the case for South African schools that have weathered... -
Impact of climate change on yield and water use efficiencies of potato in different production regions of South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: AC Franke --- , South Africa LN Muelelwa --- , South Africa JM Steyn --- , South AfricaIn South Africa, the potato is produced in regions with different climates. Climate change is expected to result in higher temperatures, thus increasing the incidence of heat stress, but lowering the risk of frosts in mid-altitude areas. Increasing ambient carbon... -
Flat model structures under excellent extensions
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Wei Ren --- , ChinaWe prove that the weak equivalences, cofibrations and fibrations in Gillespie’s flat model structure are invariant under excellent extensions of rings. As applications, the flat and cotorsion dimensions of unbounded complexes along excellent extensions are investigated, and moreover, some homological... -
A systems-based R&D management model for the road and transport engineering sector applied to a community access roads and transport research programme
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Frederik Christoffel Rust --- , South Africa Leslie Roy Sampson --- , South AfricaA conceptual non-linear, systems-based R&D management model for the road and transport sector was developed to address the associated complexities of transport and road research. It takes account of all the elements of the innovation value chain as well as... -
Are South African linefishes recovering and what makes them prone to overexploitation?
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Haupt --- , South Africa H Winker --- , South Africa D Parker --- , South Africa SE Kerwath --- , South AfricaManaging coastal fisheries is challenging as the status of many fish stocks caught in these fisheries remains unknown. In the South African linefishery, regular comprehensive assessments of the status of most linefish stocks are unattainable owing to a scarcity of... -
Adoption determinants of multiple climate smart agricultural technologies in Zimbabwe: Considerations for scaling-up and out
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Angeline Mujeyi --- , South Africa Maxwell Mudhara --- , South Africa Munyaradzi J. Mutenje --- , ZimbabweUsing a multistage sampling technique, data were collected from 386 households in four districts of Zimbabwe to investigate current Climate Smart Agriculture (CSA) technology combinations smallholder farmers practising integrated crop-livestock farming are adopting, as well as the determinants of adoption... -
Information acquisition and adoption of conservation agriculture by smallholder farmers in South-West Nigeria: Recursive bivariate probit estimation
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Seyi Olalekan Olawuyi --- , South Africa Abbyssinia Mushunje --- , South AfricaThe persistent use of traditional farming practices and cultivation of low yielding variety of crops on scattered small farmland holdings by agrarian farming households in Nigeria has put pressure on land and water resources, consequently leading to depletion of soil... -
Determination of the series resistance of a solar cell through its maximum power point
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: H. A. Koffi --- , Accra, Ghana A. A. Yankson --- , Accra, Ghana A. F. Hughes --- , Accra, Ghana K. Ampomah-Benefo --- , Accra, Ghana J. K. A. Amuzu --- , Accra, GhanaA simple analytical approach has been developed to determine the series resistance, R s, of a solar cell. The method adopted here depends only on the knowledge of the open-circuit voltage, V oc, and the current and voltage at the... -
Improving the forecasts of commercial timber volume in transition forest in the northern Brazilian Amazon
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Robson B de Lima --- , Brazil Rinaldo LC Ferreira --- , Brazil José AA da Silva --- , Brazil Marcelino C Guedes --- , Brazil Jadson C de Abreu --- , Brazil Cinthia P de Oliveira --- , Brazil Robson C Lima --- , Brazil Diego AS da Silva --- , Brazil Renan M Santos --- , Brazil Erik PF Carvalho --- , Brazil Robson M de Araújo Silva --- , BrazilThe commercial volume in tropical forests is fundamental to the implementation of sustainable forest management plans. However, in the absence of local or generic volumetric equations, most forest managers and forest services are still using traditional form factors (FF) to... -
Consumer sentiment and time-varying betas: Testing the validity of the consumption CAPM on the Johannesburg Stock Exchange
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Javier Rojo-Suárez --- , Spain Ana Belén Alonso-Conde --- , SpainWe test both the conditional and unconditional versions of the consumption capital asset pricing model (CCAPM) on the Johannesburg Stock Exchange, for the period 1988–2018, and compare its performance with that of the CAPM and the Fama-French three- and five-factor... -
Multiple GPS fix intervals show variations in the manner African White-backed Vultures Gyps africanus utilise space
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Mark Zvidzai --- , Zimbabwe Fadzai Michelle Zengeya --- , Zimbabwe Mhosisi Masocha --- , Zimbabwe Henry Ndaimani --- , Zimbabwe Amon Murwira --- , ZimbabweApplication of spatial data is becoming increasingly important as a tool for mapping and understanding space utilisation patterns especially for critically endangered species. In this study, we tested how variation in the GPS fix interval may influence space utilisation patterns... -
Will Africapitalism work?
Item type: Journal Article • Journal: Africa Journal of Management • Authors: Emmanuel Adegbite --- , UK Olabisi Daodu --- , UK Jacob Wood --- , SingaporeAfricapitalism suggests a refined capitalist system aimed at achieving collective good unlike the shareholder value maximization model of Anglo-American capitalism. It emphasizes the obligations of the private sector in Africa to pursue socio-economic development. Despite these proposed benefits, this paper... -
Validation of the ADHD-Behaviour Rating Scale for early childhood teacher use in South African classrooms
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Celeste Combrinck --- , South Africa Hannelie du Preez --- , South AfricaWe tested the construct validity of scores from the Attention Deficit Hyperactivity Disorder Behaviour-Rating Scale (ADHD-BRS) within South African early childhood classrooms in three of the eleven official languages, English, Afrikaans, and isiXhosa. In-service teachers (n = 109) from 112... -
Risk of investing in volatility products: A regime-switching approach
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Leon Li --- , New ZealandVolatility indexes provide a tool for investors to speculate and trade on market sentiment regarding future volatility. The risk of trading on volatility indexes can be measured by their second moments, namely, variance and correlation. This study considers the four... -
The wheat curl mite (Aceria tosichella, Prostigmata: Eriophyidae) could establish in South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Tamryn S Venter --- , South Africa Mark P Robertson --- , South Africa Davina L Saccaggi --- , South Africa Katelyn T Faulkner --- , South AfricaBiological invasions by agricultural pests can have serious negative impacts, including decreases in crop yield and economic losses. The MT-1 and MT-8 genotypes of the wheat curl mite (Aceria tosichella) (hereafter ‘WCM’ refers to these two genotypes) are globally distributed... -
Modelling continental range shift of the African elephant (Loxodonta africana) under a changing climate and land cover: implications for future conservation of the species
Item type: Journal Article • Journal: African Zoology • Authors: Sintayehu W Dejene --- , Ethiopia Kudzai S Mpakairi --- , Rajapandian Kanagaraj --- , Germany Yussuf A Wato --- , Kenya Sewnet Mengistu --- , EthiopiaClimate and land use change are anticipated to alter the distribution of wildlife, due to their impact on the quantity and quality of forage availability, water cycle, as well as competition for key resources. Using an ensemble of species distribution... -
Waste Disposal Sites and Residential Rental Values Nexus: An Appraisal of Agogo Asante Akyem Dumps
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Peres Ofori --- , GhanaThe study, using regression and ANOVA, assessed the extent to which waste disposal sites impact residential rental values. The research collected data from both secondary and primary sources using a mixed method cross sectional survey. The linear hedonic price model... -
Three-dimensional modelling of the circulation in False Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: F Coleman --- , South Africa GPJ Diedericks --- , South Africa AK Theron --- , South Africa J Lencart e Silva --- , United KingdomFalse Bay is the largest coastal embayment along South Africa’s coastline. Despite notable contributions of various historical observational studies on the circulation within False Bay and the associated physical processes driving these flows, there remains significant uncertainty largely because the... -
Models for predicting slenderness coefficient from stump diameter for Tectona grandis stands in south-western Nigeria
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Onyekachi Chukwu --- , NigeriaIllegal logging has continued to be a major cause of depletion of the tropical forests in developing countries. However, empirical means of estimating the growth characteristics of a removed tree, which will facilitate the conviction of illegal loggers in judicial... -
Analysing species site-specific tree growth, mortality and in-growth for miombo woodlands in Tanzania
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: E E Njoghomi --- , Tanzania S Valkonen --- , K Karlsson --- ,The silvicultural information base for the development of management regimes for Tanzanian miombo woodlands is underdeveloped. The limited and fragmented information on tree growth and stand dynamics has constrained the progress of sustainable management in these woodlands. Therefore, this study... -
Calibration and validation of APSIM–Maize, DSSAT CERES–Maize and AquaCrop models for Ethiopian tropical environments
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Hirut Getachew Feleke --- , South Africa MJ Savage --- , South Africa Kindie Tesfaye --- , EthiopiaProcess-based crop models are popular tools to quantify the impact of changes due to climate or crop management. Accurate simulation of crop production for different agro-ecological conditions using an individual crop model remains challenging due to different sources of uncertainty... -
Assessing the impact of climate change on crop production in southern Africa: a review
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: AC Franke --- , South AfricaThis paper provides a systematic review of studies assessing the impact of climate change on crop yields in southern Africa. Moreover, it synthesises the current knowledge of the impact of elevated ambient CO2 levels (eCO2) and temperatures on physiological processes,... -
Firm-specific orientations and manufacturing capability under institutional voids
Item type: Journal Article • Journal: Africa Journal of Management • Authors: Deusdedit Augustine Rwehumbiza --- , United Republic of TanzaniaManufacturing capability (MC) is widely considered to depend on a strategic orientation of firms and institutional support. Remarkably, little is known about the influence of firm-specific orientations on manufacturing capability under institutional voids. This study examines the extent to which... -
Improvements in forecasting insurance stock excess returns: Comparing the investor sentiment endurance index with the CAPM and Fama-French models
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Ling T. He --- , Haibo Yao --- , K. Michael Casey --- ,This study applies the sentiment endurance (SE) index developed by He (2012) to forecast excess returns of insurance stocks. With the exception of the 12-month rolling forecasts of the Fama-French three-factor model (FF), forecasts of the SE model persistently outperform... -
Diversity pattern of bats (Mammalia: Chiroptera) in a modified tropical environment in the western region of Cameroon
Item type: Journal Article • Journal: African Zoology • Authors: Manfothang Dongmo Ervis --- , Cameroon Bakwo Fils Eric-Moise --- , Cameroon Mongombe Manga Aaron --- , Cameroon Atagana Patrick Jules --- , Cameroon Tchuenguem Fohouo Fernand-Nestor --- , CameroonThe western region of Cameroon is one of the leading agricultural production areas in sub-Saharan Africa, and this ongoing anthropogenic perturbation has led to the replacement of natural forests with agroecosystems. Such anthropogenic landscape transformations may have affected bat species... -
Analysis of farmers’ food price volatility and Nigeria’s growth enhancement support scheme
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Joseph I. Uduji --- , Nigeria Elda Nduka Okolo-Obasi --- , Nigeria Simplice Anutechia Asongu --- , CameroonFood prices in Nigeria have become significantly higher and more volatile since 2012. The purpose of this research was to find out what affects farmers’ participation in the growth enhancement support scheme (GESS) in the country. We determined the effect... -
Social capital and project management success in a developing country environment: Mediating role of knowledge management
Item type: Journal Article • Journal: Africa Journal of Management • Authors: Kwasi Amoako-Gyampah --- , USA Moses Acquaah --- , USA Ebenezer Adaku --- , Ghana Samuel Famiyeh --- , GhanaDespite significant investments in projects by organizations, governments, and international development agencies in developing countries, many of the projects have failed and continue to fail due to budget overruns, inability to complete projects on time, and poor-quality outcomes. We draw... -
Smallholder wheat farmers’ commercialization level and its determinants in northwestern Ethiopia
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Yonnas Addis Mihretie --- , EthiopiaThis study analyzes the commercial engagement of smallholder farmers in wheat commercialization at the farm level and the factors affecting this. A stratified three stage sampling technique was used to collect data from 195 smallholder wheat farmers. Descriptive and Tobit... -
Resilience to shocks and food insecurity: Determinants, and the impact of smallholder jatropha curcas cultivation in Southern Malawi
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Owen Y. Chamdimba --- , South Africa Gerald F. Ortmann --- , South Africa Edilegnaw Wale --- , South AfricaThis paper studied household resilience to food insecurity, its determinants, and the impact of shocks on welfare in Southern Malawi. The resilience concept is evolving. A crucial issue in scholarly and policy space is how it is measured. This paper... -
Calibration and evaluation of the Sustainable Grazing Systems pasture model for predicting native grass aboveground biomass production in southern Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Walter Svinurai --- , South Africa Abubeker Hassen --- , South Africa Eyob Tesfamariam --- , South Africa Abel Ramoelo --- , South Africa Brendan Cullen --- , AustraliaSimulation modelling of grass biomass production has gained huge attention since the early 2000s, but it has rarely been applied to southern African rangelands, due to limited data availability for model calibration and evaluation. This study was conducted to calibrate... -
Barriers, benefits, and behaviour: Voluntary medical male circumcision ideation in a population-based sample of Zambian men
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Joseph G Rosen --- , USA Maria A Carrasco --- , USA Ariana M Traub --- , USA E ‘Kuor Kumoji --- , USAReaching ambitious voluntary medical male circumcision (VMMC) coverage targets requires a deeper understanding of the multifaceted processes shaping men’s willingness to access VMMC. Guided by the Ideation Model for Health Communication, this population-based study identifies correlates of Zambian men’s future... -
Multi-asset allocation of exchange traded funds: Application of Black–Litterman model
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Mei-Ling Tang --- , Taiwan Feng-Yu Wu --- , Taiwan Ming-Chin Hung --- , TaiwanThe Black–Litterman (BL) model allows investors to apply their subjective views to asset allocation optimisation. In this study, we construct a multi-asset allocation portfolio of iShares exchange traded funds (ETFs) using mean–variance (MV) and BL models. Two investment strategies, namely... -
Population parameters, exploitation rate and diet of black-chinned Tilapia, Sarotherodon melanotheron Rüppell, 1852 (Pisces: Cichlidae), from Badagry Creek, Lagos, Nigeria
Item type: Journal Article • Journal: African Zoology • Authors: Prince Emeka Ndimele --- , Nigeria Fatai Gbolahan Owodeinde --- , Nigeria Edwin Oritseweyinmi Clarke --- , Nigeria Olufemi Olusegun Whenu --- , Nigeria Olufemi Olabode Joseph --- , NigeriaThe black-chinned tilapia (Sarotherodon melanotheron) is a member of the cichlid family, which can be cultured to complement the output from a predominantly catfish aquaculture industry in Nigeria. In order to achieve this objective, it is important to study the... -
Is the largest African penguin colony in South Africa influencing local ocean productivity?
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: G Passuni --- , South Africa LRD Human --- , South Africa SN Riddick --- , United States P Pattrick --- , South Africa M Bizani --- , South Africa SHP Deyzel --- , South Africa NA Strydom --- , South Africa TG Bornman --- , South Africa L Pichegru --- , South AfricaIn coastal waters, nutrient supplies originate principally from allochthonous sources, such as inputs from rivers, estuaries or oceanic waters. Recently, it has been suggested that marine life contributes to the nutrient load, with penguin colonies being the largest contributor worldwide... -
Local variations in the response of birds to human presence in urban areas
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Tristan Nyatanga --- , Zimbabwe Henry Ndaimani --- , South Africa Tanyaradzwa Gaza --- , ZimbabweStudies that seek to understand the local variations in the response of birds to human disturbance in urban areas are important for conservation. This article investigated the contribution of human population density in the different urban land use zones of... -
Additive biomass model for Heritiera fomes (Buch.-Hum.) in the Sundarbans Reserved Forest, Bangladesh
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Mohammad Raqibul Hasan Siddique --- , Bangladesh Mahmood Hossain --- , Bangladesh SM Rubaiot Abdullah --- , Bangladesh Md. Zaheer Iqbal --- , Bangladesh Mariam Akhter --- , Bangladesh Gael Sola --- , Italy Laurent Saint-Andre --- , France Matieu Henry --- , ItalyMangroves are recognised as an important carbon sequester and therefore demand accurate biomass and carbon stock estimations. This study aimed to develop additive biomass models for Heritiera fomes, the most dominant tree species of the Sundarbans Reserved Forest in Bangladesh... -
Tweeting on COVID-19 pandemic in South Africa: LDA-based topic modelling approach
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Murimo Bethel Mutanga --- , South Africa Abdultaofeek Abayomi --- , South AfricaThe advent of COVID-19 has disrupted all facets of human lives. As of September 2020, there is no effective viral therapy for the disease, thus necessitating research efforts toward providing solutions to the diverse areas where the pandemic has wreaked... -
Factors influencing attitudes and intention to adopt financial technology services among the end-users in Lagos State, Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Yusuf Opeyemi Akinwale --- , Saudi Arabia Adam Konto Kyari --- , Saudi ArabiaFinancial technology (Fintech) innovation has brought a dynamic change to the financial sector as new products and services are offered by conventional banks and other companies offering banking services through various online platforms. The attitudes of the end-users tend to... -
Machine learning and regression models to predict multiple tree stem volumes for teak
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Ivaldo da Silva Tavares Júnior --- , Brazil Jianne Rafaela Mazzini de Souza --- , Brazil Lucas Sérgio de Sousa Lopes --- , Brazil Leonardo Pereira Fardin --- , Brazil Gianmarco Goycochea Casas --- , Brazil Ricardo Rodrigues de Oliveira Neto --- , Brazil Rodrigo Vieira Leite --- , Brazil Helio Garcia Leite --- , BrazilThe quantification of a stand’s wood stock is one of the most important procedures for Tectona spp. (teak) management. An optimal method for estimating tree volume must accommodate the variation of the data collected in the inventory. This study evaluated... -
Fatal chytridiomycosis in the Moroccan midwife toad Alytes maurus and potential distribution of Batrachochytrium dendrobatidis across Morocco
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Barbora Thumsová --- Museo Nacional de Ciencias Naturales-CSIC, Spain David Donaire-Barroso --- Personal residence, Spain El Hassan El Mouden --- Cadi Ayyad University, Morocco Jaime Bosch --- Museo Nacional de Ciencias Naturales-CSIC, SpainMultiple threats, including emerging infectious diseases, are contributing to the extinction of amphibians worldwide. One of the most devastating diseases is the fatal amphibian skin disease chytridiomycosis caused by the fungus Batrachochytrium dendrobatidis (Bd). The presence of Bd in North... -
Commercialization level and determinants of market participation of smallholder wheat farmers in northern Ethiopia
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Dubale Abate --- , Ethiopia Fikadu Mitiku --- , Ethiopia Rijalu Negash --- , EthiopiaWheat market participation improves the income and economic growth of many smallholder farmers in Ethiopia. Despite this, smallholder farmers are not enough to participate in the wheat market so that commercialization level is very low due to different factors. This... -
Soil erosion risk analysis and mapping for conservation planning at Mihtsab-Azmati micro-dam watershed, Northern Ethiopia
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Selama Gebreslassie Yebyo --- , EthiopiaThis study was conducted to quantify, analyze and map soil erosion risk areas using remotely sensed data and GIS-based Revised Universal Soil Loss Equation (RUSLE) model at Mihtsab-Azmati Irrigation Dam Watershed, Northern Ethiopia. Based on the result, the watershed has... -
Efficiency and productivity analysis of pineapple farmers in the Akwapim-South District of Ghana: A distance function approach
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Yaw Ofori-Appiah --- , Ghana Edward Ebo Onumah --- , Ghana Freda Elikplim Asem --- , GhanaThe study sought to analyze the efficiency and productivity of pineapple farmers in the Akwapim-South District of Ghana. The paper employs the stochastic translog distance function technique to analyze the influence of inputs on outputs whilst highlighting the technical efficiency... -
Technology adoption intensity and technical efficiency of maize farmers in the Techiman municipality of Ghana
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Joana Deladem Kwawu --- , Ghana Daniel Bruce Sarpong --- , Ghana Frank Agyire-Tettey --- , GhanaThis paper analyses the determinants of the intensity of adoption of improved maize technology, technical efficiency and constraints farmers faced in the Techiman Municipality of Ghana. To achieve the objectives, cross-sectional data were collected from 407 maize farmers. The data... -
The financial and social efficiency of rural cooperatives in South Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Collin L. Yobe --- , South Africa Stuart R. D. Ferrer --- , South Africa Maxwell Mudhara --- , South AfricaIdentifying the type of organization for achieving social efficiency for agricultural development remains a challenge. In this study, the relationship between the financial and social efficiency of South African agricultural cooperatives was examined. Data, comprising 1788 agricultural cooperatives, were obtained... -
Relationship between innovation, regional institutions and firm performance: Micro-evidence from Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Mohammed Seid Hussen --- , Turkey Murat Çokgezen --- , TurkeyThe main aim of this paper is to examine empirically the extent to which firm-specific action, innovation, and an external factor, the quality of regional institution, affect firms’ productivity. To this end, a firm-level dataset from 15 African countries was... -
Estimation of pesticide mixture interaction in Nile tilapia (Oreochromis niloticus) using survival analysis
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: KC Kanu --- , Nigeria NH Amaeze --- , Nigeria AA Otitoloju --- , NigeriaThe acute toxicity of the pesticides atrazine, mancozeb, chlorpyrifos and lambda-cyhalothrin, acting singly and jointly, was assessed on Nile tilapia (Oreochromis niloticus) fingerlings. Median lethal concentration (LC50), median lethal time (LT50), and mixture interaction were estimated, whereas survival analysis was... -
An analysis of the extent and use of fair value by JSE Top 40 companies
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: Wayne van Zijl --- , South Africa Valencia Hewlett --- , South AfricaFair value’s advantages, disadvantages and ideology have been debated thoroughly by academics and practitioners for decades. The few implementation papers which do exist are primarily concerned with developed economies. This gap is despite the prior literature acknowledging the likely difficulties... -
The dimensionality of the UWES-17 and UWES-9: Testing second-order and bifactor models
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Hamfrey Sanhokwe --- , ZimbabweExtant research on the factor structure of the Utrecht Work Engagement Survey (UWES) across multiple study settings has consistently produced conflicting results. The study examined the dimensionality of the UWES-17 and UWES-9 using second-order and bifactor models. Cross-sectional data were... -
Skill development and employment opportunity from Chinese migrating ‘Geese’ in sub-Saharan Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Ehizuelen Michael Mitchell Omoruyi --- , People’s Republic of ChinaConsidering Chinese FDI in sub-Saharan Africa (SSA), the paper attempts to verify if the long-existing ‘flying geese’ paradigm (FGP) might be used to clarify the headway of Chinese migrating geese transmission of skills and job generation in SSA. Notably, since... -
Development and validation of an operational multi-layered model for estimation of soil moisture at point-scale in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: L Myeni --- , South Africa ME Moeletsi --- , South Africa AD Clulow --- , South AfricaData discontinuity is the major challenge that hinders the integrity of datasets from the sparse soil moisture monitoring networks in developing countries. In this study, a simplified, multi-layered soil water balance model to estimate daily soil moisture at point-scale from... -
Variation of the relationships between lengths and weights applied to 123 fish species observed at Réunion Island (Indian Ocean)
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: D Roos --- , Réunion J Taconet --- , Réunion C Gentil --- , Réunion B Brisset --- , Réunion H Evano --- , Réunion Y Aumond --- , Réunion J Huet --- , Réunion C Lepetit --- , Réunion R Boymond-Morales --- , Réunion T Rungassamy --- , Réunion R Elleboode --- , France K Mahé --- , FranceBody length–weight (L–W) relationships of 123 fish species (122 Actinopterygii and 1 Elasmobranchii) were studied from 10 218 individuals caught around Réunion Island from 2000 to 2021. All species, except for 4 with a very small number of individuals and... -
Supporting marine spatial planning with an ecosystem model of Algoa Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: K Ortega-Cisneros --- , South Africa E Weigum --- , South Africa R Chalmers --- , South Africa S Grusd --- , South Africa AT Lombard --- , South Africa L Shannon --- , South AfricaThe Ecopath with Ecosim (EwE) modelling framework was used to develop a model of Algoa Bay and test the ecosystem impacts of the implementation of the Addo Elephant National Park Marine Protected Area (MPA). The Ecopath model included 37 functional... -
The Teacher Well-Being Scale (TWBS): Construct validity, model comparisons and measurement invariance in an Ethiopian setting
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Girum Tareke Zewude --- , Hungary Maria Hercz --- , HungaryThe present study aimed to adapt and validate the Teacher Well-Being Scale (TWBS), in an Ethiopian education setting. To test the reliability and validity of the scale, an Amharic version of the TWBS was developed and administered to a sample... -
Performance of factor models in explaining anomalous return patterns: Evidence from Pakistan
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Mehak Younus --- , Pakistan Hilal Anwar Butt --- , PakistanWe compared classic and contemporary asset pricing factor models in explaining anomalous returns in the Pakistani stock market using a sample of 290 companies listed on the Pakistan Stock Exchange. We replicated 54 anomalies with a successful replication rate of... -
The impact of the COVID-19 pandemic on people living with HIV in Zimbabwe
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Bernard Madzima --- , Zimbabwe Tatenda Makoni --- , Zimbabwe Owen Mugurungi --- , Zimbabwe Godfrey Mudariki --- , Zimbabwe Amon Mpofu --- , Zimbabwe Freeman Dube --- , Zimbabwe Lameck Munangaidzwa --- , Zimbabwe Isaac Taramusi --- , ZimbabweThe COVID-19 pandemic was reported from March 2020 in Zimbabwe. COVID-19 containment measures which included repeated lockdowns have disrupted community interactions, reduced working hours, restricted travel and restricted HIV services for people living with HIV (PLHIV), among others. The study... -
Reducing poverty through use of irrigation: Evidence from rice farming in Benin
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Gbetondji Melaine Armel Nonvide --- , BeninAn emerging body of literature has claimed that poverty is multidimensional and therefore the unidimensional measure cannot serve as a good proxy for poverty. The actual debate is about the inclusion of other dimensions in the poverty analysis framework. Regarding... -
Unlocking the commercialization potentials of Moringa oleifera production in Southwestern Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: T. O. Ojo --- , Nigeria A. A. Adetoro --- , Pietermaritzburg, South Africa A. A. Ogundeji --- , South Africa J. A. Belle --- , South Africa M. S. C. Ngidi --- , Pietermaritzburg, South AfricaDespite the importance of Moringa oleifera tree for food security at the smallholder farmers’ level, there is no consolidated socioeconomic information about the crop such as its contribution to household food security and income, and its production potential, commercialization and... -
Instigating transformative entrepreneurship in subsistence communities: Supporting leaders' transcendence and self-determination
Item type: Journal Article • Journal: Africa Journal of Management • Authors: Steven W. Rayburn --- Texas State University, USA Gideon Ochieng --- , KenyaThis research exposes a process of bottom-up development that supports leaders’ transcendent motives and self-determination needs to instigate transformative entrepreneurship within their communities. The process is illuminated by actions taken in development organizations working within subsistence communities. Findings reveal that... -
A typology of social entrepreneuring models continued: Empirical evidence from South Africa
Item type: Journal Article • Journal: Africa Journal of Management • Authors: Alex Bignotti --- University of Pretoria, South Africa Kerrin Myres --- Gordon Institute of Business Science (GIBS), University of Pretoria, South AfricaThere have been calls in social entrepreneurship research to move beyond conceptual arguments and to ground definitions and conceptualizations of this field in empirical research, especially pertaining to the developing world. Owing to the socially embedded nature of social enterprises,... -
Indicators of firm growth: Evidence from the JSE
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: Kyle Kildaire --- University of the Witwatersrand, South Africa Avani Sebastian --- University of the Witwatersrand, South Africa Warren Maroun --- University of the Witwatersrand, South AfricaThe estimation of firm growth is increasingly relevant to providers of capital in periods of economic uncertainty. The current study employs univariate and multivariate analyses to assess the impact of real GDP and the dividend payout ratio on earnings growth... -
Farm-scale digital soil mapping of soil classes in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Trevan Flynn --- , Czech Republic Andrei Rozanov --- , South Africa Freddie Ellis --- , South Africa Willem de Clercq --- , South Africa Cathy Clarke --- , South AfricaThis study involved the evaluation of farm-scale digital soil classification in the Sandspruit catchment of the Western Cape Province, South Africa. The study aimed to evaluate a digital soil mapping (DSM) method, from feature selection, spatial predictions and sample design... -
A comparative review of decision support tools routinely used by selected transboundary River Basin Organisations
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: H Bukhari --- , South Africa CA Brown --- , South AfricaAs human pressures on water resources increase, the data and decision support (DS) tools used in the governance, development and management of transboundary rivers are likely to become increasingly important. There are no universal, standardised selection processes or designs for... -
A protocol and tools for setting environmental water temperature guidelines for perennial rivers in South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Helen Dallas --- , South Africa Nicholas Rivers-Moore --- , South AfricaHuman activities have cumulatively altered natural thermal regimes, with impacts and occurrences of extreme events amplified and exacerbated by global climate change. This leads to cascading ecological impacts in river systems. This paper translates knowledge generated over more than ten... -
Factors driving business model innovation in sample case studies in South Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Ignitia Motjolopane --- , South Africa Ephias Ruhode --- , South AfricaIn an environment of changing customer needs, technological advancement and digitization, the importance of business model innovation in supporting companies to accrue benefits from increased digitization while counteracting threats has intensified. Factors driving business model innovation could be of value... -
Education’s effect on food and monetary security in Burkina Faso: A joint semi-parametric and spatial analysis
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Ibrahim Niankara --- , UAEThough adversely impacted by the recent COVID-19 crisis, households’ consumption of food and non-food items are essential components of well-being worldwide. Against this background, the present analysis tests human capital theory predictions by assessing the resilience effect of formal education... -
Habitat selection and foraging preference of the endangered addax (Addax nasomaculatus) in a fenced wildlife reserve within its historic range: insights for supporting effective reintroduction
Item type: Journal Article • Journal: African Zoology • Authors: Mohsen Chammem --- , Tunisia Hicham Seri --- , Tunisia Rita Bastos --- , Portugal Mário Santos --- , Portugal Joana Vicente --- , Portugal Touhami Khorchani --- , Tunisia João Alexandre Cabral --- , PortugalReintroduction of species should be based on ecological knowledge, which is fundamental to enhancing the probability of success, but also in predicting the response to future changing landscapes. The addax (Addax nasomaculatus), an endangered antelope whose ecology is mostly unknown,... -
Crested Guineafowl and samango monkey associations
Item type: Journal Article • Journal: African Zoology • Authors: Jacco J Leemans --- , The Netherlands Birthe Linden --- , South Africa Frank van Langevelde --- , The NetherlandsAssociations between animals of different species have been observed for a large variety of taxa. These polyspecific groups are thought to provide advantages to at least one of the species involved, especially foraging benefits or reduced predation risk. In the... -
Closed-form solutions via the invariant approach for one-factor commodity models
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: A.G. Johnpillai --- Eastern University, Sri Lanka F.M. Mahomed --- University of the Witwatersrand, South AfricaWe utilise the invariant method for scalar linear (1+1) parabolic partial differential equations so as to effect reductions via invertible transformations to Lie canonical forms of the first and third types. This is performed for the one-factor commodity models that... -
Status quo of the South African clothing industry’s university-industry-government collaborations
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Sipho Mbatha --- Tshwane University of Technology, South Africa Anne Mastamet-Mason --- Tshwane University of Technology, South AfricaThe South African clothing industry is among the industries viewed as strategic for socio-economic development by the South African government. The government’s industrial policies incorporated University-Industry-Government (UIG) Research and Development (R&D) collaborations in efforts to achieve the United Nation’s Sustainable... -
The association between internal migration and teenage fertility control: A South African study
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Sibusiso Mkwananzi --- Institute for Gender Studies, University of South Africa, South AfricaThis study investigated the association between internal migration, as a form of residential mobility, and teenage fertility in South Africa. Data were from the 2001 and 2011 South African censuses, n 2001 = 335 065 and n 2011 = 316... -
Estimating the cost and efficiency gain of rolling out a multi-month dispensing programme for antiretroviral treatment in Tanzania
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: George Ruhago --- Muhimbili University of Health and Allied Sciences, Tanzania Steven Forsythe --- , USA Roland Van de Ven --- , USA Louis Apicella --- , USABackground: Globally, efforts to curtail the HIV pandemic are growing. The Joint United Nations Programme on HIV and AIDS (UNAIDS) and partners set the 95-95-95 targets to be achieved by 2025. Tanzania’s ongoing transition from single-month ARV to longer multi-month... -
Long-term experimental data and crop modelling to inform the ecological intensification of irrigated wheat production in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: S Magwaza --- University of Pretoria, South Africa M van der Laan --- University of Pretoria, South Africa D Marais --- University of Pretoria, South AfricaWheat (Triticum aestivum L.) production is threatened by climate change and the decline in agricultural land available due to urbanisation, farmers switching to other crops, and environmental degradation. The aim of this study was to investigate the ecological intensification (EI)... -
Enhancing predictive precision of dominant height projection equations for eucalypts by incorporating rainfall and temperature terms
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Brian G Mandigora --- Stellenbosch University, South Africa David M Drew --- Stellenbosch University, South AfricaShort-rotation forest stands are sensitive to extreme climate conditions during their growth period, which presents a challenge to managing forests and modelling forest growth in a constantly changing climate. We developed climate-sensitive dominant height models for the Eucalyptus grandis ×... -
Human resources and innovation capability: Evidences from Nigeria food and beverage firms
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Helen Olubunmi Aderemi --- Obafemi Awolowo University, Nigeria Victor Oluwasina Sobanke --- National Centre for Technology Management (NACETEM), Nigeria Matthew Olugbemiga Ilori --- Obafemi Awolowo University, NigeriaHuman resources are recognized as the ultimate and most indispensable resource in economic development. In this study, an inquiry was made to ascertain the determinants of workers’ innovativeness. A survey of 229 respondents in food and beverage processing firms selected... -
Developing an improved reverse engineering adoption model towards the improvement of performance in metal engineering industries
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Yichalewal Goshime --- Addis Ababa Institute of Technology, Addis Ababa University, Ethiopia Daniel Kitaw --- Addis Ababa Institute of Technology, Addis Ababa University, Ethiopia Frank Ebinger --- Erlangen University, George Simon Ohm Technical Institute, Nuremberg Campus of Technology, Germany Kassu Jilcha --- Addis Ababa Institute of Technology, Addis Ababa University, EthiopiaPurpose: This research aims to develop an improved model that promotes reverse engineering /RE/ practice in metal engineering industries (MEIs). RE is one cost-effective technology transfer /TT/ and innovation method that improves organizational performance. However, only a few scholars have... -
Technology management practices and innovation: Empirical evidence from medium- and large-scale manufacturing firms in Ethiopia
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Mesfin Mala Kalko --- Tomas Bata University in Zlin, Czech Republic Obsa Teferi Erena --- Hawassa University, Ethiopia Sara Adugna Debele --- Hawassa University, EthiopiaIn order to investigate empirically the effects of technology management on firm innovation, this paper considers the antecedents and multidimensional views of technology management mechanisms on innovation performance in medium- and large-scale manufacturing firms in a developing country, namely Ethiopia... -
Culture and African contexts of HIV/AIDS prevention, care and support
Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Collins O. Airhihenbuwa --- Department of Biobehavioral Health, Pennsylvania State University, J. DeWitt Webster --- Department of Health Management and Policy, University of Michigan School of Public Health,Culture plays a vital role in determining the level of health of the individual, the family and the community. This is particularly relevant in the context of Africa, where the values of extended family and community significantly influence the behaviour... -
Estimates of eligibility for antiretroviral treatment (ART) and projected ART impact on AIDS mortality among South African educators
Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Thomas M Rehle --- HSRC's Social Aspects of HIV/AIDS and Health Programme, Olive Shisana --- South African Human Sciences Research Council,The study assessed the proportion of HIV-infected educators that need antiretroviral treatment (ART) according to current criteria, and estimated the impact of ART on AIDS mortality by modelling scenarios with and without access to ART. Specimens for HIV testing were... -
Factors influencing condom use among women in Ghana: an HIV/AIDS perspective
Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Philip Baiden --- Department of Sociology, University of Western Ontario, Fernando Rajulton --- Department of Sociology, University of Western Ontario,Although in Ghana information on HIV infection and prevention, both in terms of quality and quantity, has increased considerably within the past few years, available literature indicates that behaviour change is yet to correspond with the amount of information and... -
Application of the information, motivation and behavioural skills model for targeting HIV risk behaviour amongst adolescent learners in South Africa
Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Misheck Ndebele [d94e14] Mambwe Kasese-Hara Michael GreylingThis paper discusses the application of an information, motivation and behavioural skills (IMB) model in a school-based programme for the reduction of HIV risk behaviour among 259 Grade 11 learners in two high schools in Alexandra township, Johannesburg. School 1... -
An evaluation of the innovative potentials of a HIV pilot exploring medical pluralism in rural South Africa
Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Christopher J. Burman --- , South AfricaThis article reflects on an internal evaluation undertaken to estimate the potentials of a community-university pilot project to be developed into a bonafide innovation that can be applied at scale. The focus of the community-university partnership has been to reduce... -
A model to understand HIV-related stigma and the psychosocial well-being of children orphaned by AIDS: a theory generative approach
Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Z. Yassin --- University of the Western Cape, South Africa C. Erasmus --- University of the Western Cape, South Africa J. Frantz --- University of the Western Cape, South AfricaHIV-related stigma has negatively impacted the psychosocial well-being of children who have been orphaned by AIDS-related causes. Response to reducing stigma and ensuring child well-being is hindered by the limited understanding of HIV-related stigma and how it affects the psychosocial... -
Explicating factors that explain condom use intention among in-school adolescents in Botswana: a structural equation modelling approach
Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Kolentino N. Mpeta --- North West University, South Africa Ntebogang D. Moroke --- North West University, South Africa Lesego Gabaitiri --- Botswana International University of Science and Technology, BotswanaKnowledge with respect to adolescents’ intentions to engage in protective sexual behaviours is still deficient in numerous countries around the world, particularly in Sub-Saharan Africa (SSA) where HIV prevalence is the highest. Increasing cross-sectional research suggests that the theory of... -
Assessing sexual practices and beliefs among university students in Khartoum, Sudan; a qualitative study
Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Husameddin Farouk Elshiekh --- Maastricht University, The Netherlands Hein de Vries --- Maastricht University, The Netherlands Ciska Hoving --- Maastricht University, The NetherlandsUniversity students in Sudan are more at risk of contracting HIV than the general population, due to a high rate of sexual activity and low uptake of preventive measures such as condoms. Hence, they are considered an important target for... -
Conservation status of herpetofauna endemic to Kwazulu‐Natal
Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: AdrianJ. Armstrong --- KwaZulu‐Natal Nature Conservation Service, South AfricaThe KwaZulu‐Natal Nature Conservation Service is undertaking a long‐term project to determine the value of untransformed land for biodiversity conservation, to map these areas in accordance with their relative values, and to identify and prioritise irreplaceable areas. Existing distribution data... -
Aggregation in Bibron's gecko, chondrodactylus bibronii
Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: Anita Meyer --- University of Stellenbosch, South Africa P. le FrasN. Mouton --- University of Stellenbosch, South AfricaAggregation behaviour in a rock‐dwelling gecko Chondrodactylus bibronii was investigated. In a laboratory setup, individuals were provided with an excess of shelters to determine whether limited availability of optimal shelters may be the cause of this species’ aggregation behaviour in... -
Potential effects of predicted climate change on the endemic South African Dwarf Chameleons, Bradypodion
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: DarrenT. Houniet --- South African National Biodiversity Institute, South Africa Wilfried Thuiller --- Université J. Fourier, France KrystalA. Tolley --- South African National Biodiversity Institute, South AfricaThe niche concept implies that a relationship exists between a species and its environment, while macro‐ecological theory suggests that an important attribute of a species’ environment is climate. Thus, changes in climate could affect individual species, but also communities. Here,... -
Distribution and conservation of the coastal population of the black-headed dwarf chameleon Bradypodion melanocephalum in KwaZulu-Natal
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: AdrianJ. Armstrong --- Ezemvelo Kzn Wildlife, South AfricaThe coastal population of the black-headed dwarf chameleon Bradypodion melanocephalum in KwaZulu-Natal appears to be centred on the eThekwini Municipal Area, which is experiencing rapid urban development. This population occurs in few statutory protected areas, all of which are small... -
Using modern models to test Poynton's predictions
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Clemens Schreiner --- Zoologisches Forschungmuseum Alexander Koenig, Germany Dennis Rödder --- Zoologisches Forschungmuseum Alexander Koenig, Germany G. John Measey --- Nelson Mandela Metropolitan University, South AfricaIn his seminal work ‘The Amphibia of southern Africa: a faunal study’, Poynton identified and contrasted two centres of amphibian importance, the temperate south-western Cape (“Cape”) and tropical northeast (“Tropical”). With reference to the dominant role of climate fluctuations resulting... -
Business-driven approach to cloud computing adoption by small businesses
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Martin Adane --- University of Cape Coast, GhanaIn the adoption of technology, there is the need for the alignment of the objectives of the business’s information technology (IT) strategy with the business strategy to ensure effectiveness and overall business performance. This study sought to investigate the effect... -
Validation of growth zone formation in Oreochromis mossambicus otoliths collected from an irrigation pond in the Sundays River Valley, Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L Mofu --- Rhodes University, South Africa T Dalu --- University of Mpumalanga, South Africa RJ Wasserman --- South African Institute for Aquatic Biodiversity, South Africa DJ Woodford --- University of the Witwatersrand, South Africa OLF Weyl --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaIn fisheries science, life-history trait information is widely used to estimate fish population recruitment, growth, and mortality. The aging and growth of Oreochromis mossambicus from the Sundays River Valley irrigation pond in the Eastern Cape province of South Africa were... -
A photo-identification-based assessment model of southern right whales Eubalaena australis surveyed in South African waters, with a focus on recent low counts of mothers with calves
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Brandão --- University of Cape Town, South Africa A Ross-Gillespie --- University of Cape Town, South Africa E Vermeulen --- University of Pretoria, South Africa DS Butterworth --- University of Cape Town, South AfricaPhoto-identification data for southern right whale cow–calf pairs on the South African calving grounds provide one of the longest abundance time-series for any whale population worldwide. Following a very steady increase from a heavily depleted state, surveys since 2015 reflect... -
Tropical wood species: alternative model to determine the characteristic compressive strength perpendicular to grain
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Arthur Filipe Freire Gomes --- Federal University of São Carlos (UFSCar), Brazil Fernando Júnior Resende Macarenhas --- Rua Luís Reis Santos - Pólo II, University of Coimbra, Portugal Diego Henrique de Almeida --- Federal University of São Carlos (UFSCar), Brazil Alfredo Manuel Pereira Geraldes Dias --- Rua Luís Reis Santos - Pólo II, University of Coimbra, Portugal Tulio Hallak Panzera --- Federal University of São João Del Rey (UFSJ), Brazil Francisco Antônio Rocco Lahr --- University of São Paulo (USP), Brazil André Luis Christoforo --- Federal University of São Carlos (UFSCar), BrazilBrazil has a vast area of native forests with the potential to be sustainably exploited for application in civil construction. Density is a key factor when analysing the characteristics of different wood species and their future uses, and additionally it... -
Nonlinear dependencies in the Fama and French three-factor model
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Jakub Bandurski --- University of Warsaw, Poland Łukasz Postek --- University of Warsaw, PolandThis article addresses the topic of nonlinear dependencies in the Fama and French three-factor model. Five time-series models, including nonlinear terms, are assessed using US and European data and compared with a benchmark linear model. The analysis found that nonlinear... -
The model theory of commutative near-vector spaces
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Karin-Therese Howell --- Stellenbosch University, SA Charlotte Kestner --- Imperial College London, UKIn this paper we study near-vector spaces over a commutative F from a model theoretic point of view. In this context we show regular near-vector spaces are in fact vector spaces. We find that near-vector spaces are not first-order axiomatisable,... -
Explicating the adoption of an innovation Fintech Value Chain Financing from Aarti (Middlemen) perspective in Pakistan
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Sayeda Zeenat Maryam --- University of the Punjab, Pakistan Ashfaq Ahmed --- University of the Punjab, Pakistan Syed Waqar Haider --- Govt. College for Women University, Pakistan Tasneem Akhter --- University of Central Punjab, PakistanIn the wake of the 2008 global financial crisis, the Fintech industry and Islamic banking were striving to fill the existing void through innovation and different business approaches. Losing trust in conventional banking, advancement of technology and internet globally, and... -
Towards developing a national framework for industry 4.0 in African emerging economies
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Olugbenga Ayo Ojubanire --- Euromed University of Fes, Morocco Hicham Sebti --- Euromed University of Fes, Morocco Sabrina Berbain --- ISG International Business School, FranceUnlike past industrial eras, the Fourth Industrial Revolution (industry 4.0) is accelerated and continues to gain momentum. While developed economies are making remarkable progress and contributing geometrically to the global value chain, African emerging economies have continued to grapple with... -
The determinants of the intention to use autonomous vehicles
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Paul Orsot-Dessi --- Université Bourgogne Franche-Comté, France Arvind Ashta --- Université Bourgogne Franche-Comté, France Surender Mor --- BPS Women University, IndiaThis study measures the relative importance of the determinants of the intentions to use autonomous vehicles. We hypothesize that the intention to use is influenced by perceived usefulness and perceived ease and that the perceived usefulness will be determined by... -
Predictive modelling to determine the attainable moisture content of Alstonia boonei wood using a solar kiln dryer
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Joy Aduralere Ogunsuyi --- Federal University of Technology Akure (FUTA), Nigeria Jacob Mayowa Owoyemi --- Federal University of Technology Akure (FUTA), Nigeria Olusola Samuel Makinde --- Federal University of Technology Akure (FUTA), NigeriaModelling of wood drying is important for predicting the performance and efficiency of solar dryers and to optimise the drying process during each season of the year. The attainable moisture content (MC) of Alstonia boonei wood was studied when dried... -
Managers’ perception of ethics in public entities and service delivery using the corporate virtue scale
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Priviledge Cheteni --- , East London, South Africa Emmanuel Selemani Shindika --- President’s Office, Public Service Management, Tanzania Public Service College, TanzaniaEthical culture is the epitome of the success of various organizations and a prerequisite for progress. This study aimed to examine the construct validity of the Corporate Virtue Scale (CEV) and find if there is any association between ethical culture... -
Predicting tax fraud using supervised machine learning approach
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Belle Fille Murorunkwere --- University of Rwanda, Rwanda Revenue Authority, Dominique Haughton --- Université Paris 1 (SAMM), Joseph Nzabanita --- University of Rwanda, Francis Kipkogei --- Stepwise Inc, Kenya Ignace Kabano --- College of Business and Economics/University of Rwanda,With the advancement in technology, the tax base in Rwanda has become broader, and as a result, tax fraud is growing. Depending on the dataset used, fraud detection experts and researchers have used different methods to identify questionable cases. This... -
Workplace factors that influence creativity and innovation in micro and small scale enterprises: Enterprise level analysis
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Samuel Godadaw Ayinaddis --- Woldia University, EthiopiaThis study examines the influence of workplace factors on creativity and innovation in micro and small enterprises (MSEs). The study is based on the componential model of organizational creativity to confirm the determinants of creativity of MSEs in the workplace... -
A gendered approach to determinants of adoption of cassava-legume intensification technology and its impact on households’ poverty status in innovation platforms of Southwestern Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Adewumi Titus Adesiyan --- Obafemi Awolowo University, Nigeria Imole Rafael Olaniyan --- Obafemi Awolowo University, Nigeria Hyeladi Ibrahim Gaya --- University of Maiduguri, Nigeria Ayodeji Damilola Kehinde --- Obafemi Awolowo University, NigeriaThe scourge of poverty has spread over Nigeria. Efforts to address the problem have yielded no tangible results. This study investigated a gendered approach to determinants of adoption of cassava-legume intensification technology and its impact on households’ poverty status in... -
Job insecurity and employee commitment during COVID-19: mediating the role of quitting intention in family-owned hotels
Item type: Journal Article • Journal: Research in Hospitality Management • Authors: Esther Theresa Appaw-Agbola --- Ho Technical University, Ghana Jennifer Eyram Nkrow --- Ho Technical University, Ghana Elikem Krampa --- Ho Technical University, GhanaUsing the social exchange theory, this article explores how quitting intention mediates job insecurity and organisational commitment in family-owned hotels during the COVID-19 period in Ghana. A conceptual model was developed to give a clear perspective of the study. Literature... -
A demonstration of the value of recapture data for informing moult phenology models for avian species with imperfect moult data
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Philipp H Boersch-Supan --- , United Kingdom Alan Tristram Kenneth Lee --- University of Cape Town, South Africa Hans-Dieter Oschadleus --- University of KwaZulu-Natal, South AfricaThe Underhill–Zucchini model has revolutionised the study of moult in the context of birds’ annual cycles, but, as for all statistical models, inferences are vulnerable to violations of model assumptions. In particular, the standard Underhill–Zucchini models for moult phenology are... -
Primary moult in the annual cycle of adult African Oystercatchers Haematopus moquini
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Taylyn C Bate --- University of Cape Town, South Africa Peter G Ryan --- University of Cape Town, South Africa Les G Underhill --- University of Cape Town, South AfricaAfrican Oystercatchers Haematopus moquini are sedentary, intertidal foraging birds, range-restricted to Namibia and South Africa. Their annual cycle has two components: breeding and moult. The Underhill–Zucchini model estimated a primary moult duration of 154 days, and mean start and completion... -
Primary moult of adult Laughing Doves Spilopelia senegalensis: introduction of the relative duration index and a comparison of moult indices
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Tanya Scott --- University of Cape Town, South Africa Les G Underhill --- University of Cape Town, South Africa George D Underhill --- University of Cape Town, South AfricaA new moult index, the relative duration index (RDI), was developed to quantify progress through moult using the Underhill–Zucchini model of primary avian moult, with the Laughing Dove Spilopelia senegalensis as a case study. The RDI weights individual primaries in... -
The primary moult of adult Red-headed Finches Amadina erythrocephala
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: T Scott --- University of Cape Town, South Africa JMH Raijmakers --- , South Africa LG Underhill --- University of Cape Town, South AfricaLittle is known about the biology of the Red-headed Finch Amadina erythrocephala. This study investigates its primary moult, the first aspect of its life history to be looked at in depth. Additionally, we used a modified Cook’s distance algorithm to... -
Influence of groups of points on estimates of the parameters of moult
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Les G Underhill --- University of Cape Town, South Africa Tanya Scott --- University of Cape Town, South AfricaThe Underhill–Zucchini model of avian moult is a statistical simplification for the analysis of primary moult, a complex biological system in birds. As with all such models, conclusions can be biased if a subset of the data used to fit... -
Using generalised additive models to visualise the annual cycle of primary feather moult patterns
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Rebecca R Irons --- University of Cape Town, South Africa Alan TK Lee --- University of Cape Town, South Africa Robert L Thomson --- University of Cape Town, South Africa Birgit Erni --- University of Cape Town, South AfricaMoult is a vital but energy-demanding event in a bird's phenological cycle. Primary moult is the shedding of old feathers and the regeneration of new flight feathers to maintain efficient functioning of these critical structures. Life history events, such as... -
The impact of news on South African sovereign bond yields
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Elizabeth-Ann van der Westhuizen --- University of Pretoria, South Africa Leon Marx Brümmer --- University of Pretoria, South Africa Cornelis Hendrik van Schalkwyk --- University of Pretoria, South AfricaA reverse event study approach was used to investigate how the South African sovereign bond yield curve reacts to headline news. The change in daily yields, calculated as the difference between the natural log of zero-coupon yields on consecutive business... -
The influence of crises on the financial position of multinationals in emerging markets
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Peter Vaz da Fonseca --- Mackenzie Presbyterian University, Brazil Michele Nascimento Jucá --- Mackenzie Presbyterian University, Brazil João Paulo da Torre Vieito --- Polytechnic Institute of Viana do Castelo, PortugalThis investigation is one of the first to analyse the relationships between leverage and bankruptcy costs, interest expenses, tax benefits and firm value, in multinational and domestic companies, during periods of crisis and financial stability. The analysed data are related... -
Return and volatility connectedness across stock markets: A global perspective
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Huifu Nong --- School of Economics, Guangxi Minzu University, ChinaThe connectedness of stock markets is inevitable because of the rapid increases in global financialisation, financial liberalisation, and integration of national economies. This study therefore increases the number of stock markets included in the LASSO-VAR model to separately estimate the... -
Distribution, habitat and vulnerability to climate change of the Endangered Leptopelis xenodactylus
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Kirsty J. Kyle --- North-West University, South Africa Louis H. Du Preez --- North-West University, South Africa James Harvey --- 41 Devonshire Avenue, South Africa Adrian J. Armstrong --- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, South AfricaLeptopelis xenodactylus is a little-known, Endangered species of frog that is thought to be endemic to the KwaZulu-Natal Province of South Africa. In an effort to determine the distribution of this species more accurately, a working species distribution model was... -
New distribution records and population density of the Critically Endangered Tarzan Chameleon (Calumma tarzan), eastern Madagascar
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Alain JV Rakotondrina --- Madagasikara Voakajy, Madagascar Raphali R Andriantsimanarilafy --- Madagasikara Voakajy, Madagascar Hanta J Razafimanahaka --- Madagasikara Voakajy, Madagascar Achille P Raselimanana --- , Madagascar Rikki Gumbs --- Zoological Society of London, United Kingdom Caleb Ofori-Boateng --- Zoological Society of London, United Kingdom Jody M Taft --- South African National Biodiversity Institute, Kirstenbosch Research Centre, South Africa Fanomezana M Ratsoavina --- Université d’Antananarivo, MadagascarThe distribution and population density of the Critically Endangered Tarzan Chameleon (Calumma tarzan) in eastern humid forests of Madagascar was studied using line transect-distance sampling. Based on the results from species distribution models, eight sites were visited over a four-month... -
Health provider administration functions, patient satisfaction, and loyalty: Their mediation by patient healthcare service quality perceptions
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Geoffrey Bentum-Micah --- Zhejiang Normal University, China Lianyu Cai --- Zhejiang Normal University, China Sampson Agyapong Atuahene --- Zhejiang Normal University, China Moses Agyemang Ameyaw --- Zhejiang Normal University, China Victor Bondzie-Micah --- Hong Kong Baptist University, Hong Kong Stephen Sarfo Adu-Yeboah --- Hefei University of Technology, ChinaThe study tested a health service quality mediation model on patient satisfaction and loyalty outcomes with provider administration functions. Participants were 7 108 outpatients from eleven public hospitals in Hubei province, China (female = 58.5%; infections and chronic diseases =... -
Susceptibility of dwarf chameleons to climate and land use change: a vulnerability framework for conservation planning
Item type: Journal Article • Journal: African Zoology • Authors: Tyron K Clark --- University of the Witwatersrand, South Africa Graham J Alexander --- University of the Witwatersrand, South Africa Krystal A Tolley --- South African National Biodiversity Institute, South AfricaClimate and land use changes are eroding biodiversity globally, and reptiles are highlighted as being particularly susceptible. In South Africa, global changes threaten the persistence of an assemblage of dwarf chameleons (Bradypodion) located in a biodiversity hotspot. We used ecological... -
Social anxiety and problematic social network site use: The sequential mediating role of self-esteem and self-concept clarity
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Jing Wu --- Shaoxing University, China Xu Zhang --- Shaoxing University, China Yuan Gao --- Shaoxing University, China Qianxiu Xiao --- Shaoxing University, ChinaThis study explored the relationship between social anxiety and problematic social network sites use and the mediating role of self-esteem and self-concept clarity. A total of 811 college students (female= 58.2%; mean age= 19.18 years, SD = 1.12 years) completed... -
Gender differences in the pathway of childhood trauma, impulsivity and adult eating behaviour: a cross-sectional study
Item type: Journal Article • Journal: Journal of Child & Adolescent Mental Health • Authors: Antônio Bonfada Collares Machado --- Institute of Psychology, Federal University of Rio Grande do Sul, Brazil Katia Irie Teruya --- Institute of Psychology, Federal University of Rio Grande do Sul, Brazil Rogério Friedman --- Universidade Federal do Rio Grande do Sul, Brazil Gibson Juliano Weydmann --- Institute of Psychology, Federal University of Rio Grande do Sul, Brazil Eduardo Remor --- Institute of Psychology, Federal University of Rio Grande do Sul, Brazil Lisiane Bizarro --- Institute of Psychology, Federal University of Rio Grande do Sul, BrazilObjective: The current cross-sectional study aimed to examine the association between childhood trauma, impulsivity, binge eating symptoms, and body mass index (BMI) in a sample of males and females. We also aimed to investigate the indirect association of childhood trauma... -
Assessment of factors driving cryptocurrency investment decision in Africa: A case of Bitcoin in Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Ibrahim Abiodun Oladapo --- Imam Abdulrahman Bin Faisal University, Saudi ArabiaThis study aims to examine the factors that influence Nigerian investors decision to participate in the Bitcoin market. The study develops a model that integrates awareness, religious beliefs, and trust alongside the theory of reasoned action’s key explanatory factor. A... -
Is mindfulness associated with lower online trolling among adolescents? Mediating effects of self-esteem and depression and moderating effect of dark personality traits
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Fang Li --- Sichuan Normal University, China Xu Tang --- Sichuan Normal University, China Xin Ge --- , China Mengni Yu --- Sichuan Normal University, China Siqi Wang --- Sichuan Normal University, China Biyun Wu --- Guangzhou University of Chinese Medicine, ChinaWe investigated the relationship between mindfulness and online trolling among adolescents. We also explored the mediating role of self-esteem and depression and the moderating role of dark personality traits in the relationship between mindfulness and online trolling. Chinese adolescents (n... -
Examining cryptocurrency usage by technology acceptance model in the Turkish context
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Asli Derlek Kocabas --- Yalova University, Turkiye Eyup Calik --- Yalova University, Turkiye Basak Cetinguc --- Yalova University, TurkiyeIn recent times, the usage of cryptocurrencies has become remarkably widespread in e-commerce applications. This study aims to explain the factors affecting cryptocurrencies by proposing an extended technology acceptance model (TAM) consisting of perceived ease of use, perceived usefulness, trust,... -
Evolutionary relationships in the African frog family Ptychadenidae, including the first molecular analysis, range extension, and distribution modelling of the monotypic genus Lanzarana
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Tadeáš Nečas --- , Czech Republic Tomáš Mazuch --- Mendel University, Czech Republic Janis Czurda --- , Czech Republic Hassan Sh Abdirahman Elmi --- Charles University, Czech Republic Mark-Oliver Rödel --- , Germany Václav Gvoždík --- , Czech RepublicThe family Ptychadenidae contains three ecologically and morphologically distinct genera: the widespread, species-rich and above-ground dwelling Ptychadena, the less widespread and diverse, burrowing Hildebrandtia, and the little-known, burrowing, monotypic Lanzarana, endemic to Somalia. Previous morphological studies placed Lanzarana in a... -
Partitioning the sources of sediment organic carbon in South African seagrass meadows
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Bossert --- Stellenbosch University, South Africa S von der Heyden --- Stellenbosch University, South Africa J Colling --- Stellenbosch University, South Africa A Ndhlovu --- Stellenbosch University, South AfricaIn the sediments of seagrass meadows, allochthonous carbon sources can account for 50–90% of sediment organic carbon (SOC), in which non-seagrass carbon is derived from external organic matter advected into the meadow’s sediments or trapped by the seagrass canopy. Identifying... -
Performance of Green vis-à-vis Red EU securities
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Ferdinantos Kottas --- National University of Ireland Maynooth, IrelandThis research compares the performance of Green (eco-friendly) versus Red (eco-enemy) returns for EU securities. Green securities are the stocks of companies whose primary business activities focus on being relatively beneficial to the environment, while Red stocks are associated with... -
On (k, ℓ)-locating colorings of graphs
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Michael A. Henning --- University of Johannesburg, South Africa Mostafa Tavakoli --- Ferdowsi University of Mashhad, IranLet c: V(G) → {1, . . . , ℓ} = [ℓ] be a proper vertex coloring of G and C(i) = {u ∈ V(G): c(u) = i} for i ∈ [ℓ]. The k-color code rk (v|c) of vertex v... -
Transformational leadership and financial employees’ unethical pro-organisational behaviour: A cognitive perspective
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Hu Zhengyan --- Henan University, China Enhui Cao --- Henan University, China Junzhe Zhao --- Henan University, China Minghui Wang --- Henan University, ChinaWe examined the relationship between transformational leadership and financial employees' unethical pro-organisational behaviour, accounting for organisational identity and future focus in the context of the Chinese organisational culture. Participants were 94 business leaders and 176 financial employees mainly from the... -
Impact of climate change on the distribution of the invasive water hyacinth in Ethiopia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Abdulbasit Hussein --- School of Natural Resources Management and Environmental Sciences, College of Agriculture and Environmental Sciences, Haramaya University, Ethiopia Solomon Estifanos --- School of Natural Resources Management and Environmental Sciences, College of Agriculture and Environmental Sciences, Haramaya University, Ethiopia Tolesa Negese --- School of Natural Resources Management and Environmental Sciences, College of Agriculture and Environmental Sciences, Haramaya University, EthiopiaThe introduction of exotic species poses one of the greatest threats to biodiversity globally. Water hyacinth is a dangerous invasive species that has harmed Ethiopia’s wetland ecology and economy. This research aims to evaluate the current distribution of water hyacinth... -
Calibration and evaluation of a CROPGRO Perennial Forage Model for Brachiaria humidicola yield simulation under future climate in subhumid environments of Ethiopia
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Fantahun Dereje --- Wallaga University, Ethiopia Ashenafi Mengistu --- Addis Ababa University, Ethiopia Diriba Geleti --- Ethiopian Institute of Agricultural Research, Ethiopia Fekede Feyissa --- Ethiopian Institute of Agricultural Research, Ethiopia Diriba Diba --- Wallaga University, Ethiopia Diego Pequeno --- , Mexico Buzunesh Tesfaye --- Wallaga University, EthiopiaCrop simulation models can be employed to assess the impacts of climate change and aid in strategic planning and decision making regarding forage strategies. This study focused on calibrating and assessing the performance of the CROPGRO Perennial Forage Model in... -
Research on the influence of fiscal policy uncertainty on corporate strategic investment – Evidence from China
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Xuejiao Yu --- Central University of Finance and Economics, China Xiaomin Cao --- Central University of Finance and Economics, China Junjian Gu --- Wuhan University of Technology, ChinaCorporations should pay attention to various policies issued by The Chinese government when making strategic investment. This paper discusses the influence of fiscal policy uncertainty on corporate strategic investment and its mechanism. The results show that the uncertainty of fiscal... -
An empirical investigation of return spillover and volatility dynamics of Indian sectoral indices
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Barkha Dhingra --- Maharshi Dayanand University, India Mohit Saini --- Maharshi Dayanand University, India Mohamed Fakhfekh --- Higher Institute of Business and Administration of Sfax, Tunisia Mahender Yadav --- Maharshi Dayanand University, IndiaThis research delves into the interconnectedness and volatility dynamics within sectoral indices amid the COVID-19 pandemic, to determine the most appropriate model for elucidating these dynamics. It addresses the burgeoning interest among investors in comprehending sectoral dynamics within India’s stock... -
The use of suitability models and remote sensing to map forest suitability: a systematic review
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Mthokozisi Ndumiso Mzuzuwentokozo Buthelezi --- University of KwaZulu-Natal, South Africa Romano Trent Lottering --- University of KwaZulu-Natal, South Africa Kabir Yunus Peerbhay --- University of KwaZulu-Natal, South Africa Onisimo Mutanga --- University of KwaZulu-Natal, South AfricaThe rapid decline of vegetated landscapes jeopardises vital ecosystem services underpinning climate change mitigation efforts. Restoring and repurposing these landscapes presents a powerful opportunity to recover lost services and strengthen the fight against climate change. This study undertook a comprehensive... -
Predicting wearable technology readiness in a South African government department: Exploring the influence of wearable technology acceptance and positive attitudes
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Henda J. Thomas --- Tshwane University of Technology, South Africa Cornelia P. J. Harmse --- Tshwane University of Technology, South Africa Cecile Schultz --- Tshwane University of Technology, South AfricaWearable technologies are anticipated to flourish in the fourth industrial revolution, enabling employers to integrate data into organizational systems. This study examined whether readiness for wearables can predict employees’ acceptance of these devices in the workplace. It explored the factors... -
Well-posedness result for the flow of Maxwell viscoelastic fluid of White-Metzner type
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Djohra Dekhil --- University of Science and Technology Houari Boumdiene USTHB, Algeria Toufik Laadj --- University of Science and Technology Houari Boumdiene USTHB, Algeria Khaled M’hamed-messaoud --- University of Science and Technology Houari Boumdiene USTHB, AlgeriaIn this paper, we investigate the flow characteristics of an unsteady quasistatic Maxwell viscoelastic fluid of White-Metzner type within a three-dimensional bounded domain. Our objective is to establish the well-posedness of the resulting partial differential equations initial boundary value problem,... -
Bayesian forecasting of stock returns on the JSE using simultaneous graphical dynamic linear models
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Nelson Kyakutwika --- Stellenbosch University, South Africa Bruce Bartlett --- Stellenbosch University, South AfricaCross-series dependencies are crucial in obtaining accurate forecasts when forecasting a multivariate time series. Simultaneous Graphical Dynamic Linear Models (SGDLMs) are Bayesian models that elegantly capture cross-series dependencies. This study forecasts returns of a 40... -
Employing behavioural portfolio theory for sustainable investment: Examining drawdown risks and ESG factors
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Aayush Poddar --- Indian Institute of Technology, India Sujoy Bhattacharya --- , R Rathish Bhatt --- Management, Goa Institute of Management, IndiaThis study uses behavioural portfolio theory (BPT) within the Markowitz Portfolio Theory framework to enhance portfolio management by focusing on sustainability and risk mitigation during market downturns. It selects portfolios to hedge against market lows using Conditional Drawdown at Risk... -
Measuring South Africa destination loyalty levels through recommending and complaining framings
Item type: Journal Article • Journal: Research in Hospitality Management • Authors: Concepción Román --- Institute of Tourism and Sustainable Economic Development, Universidad de Las Palmas de Gran Canaria, Juan Carlos Martín --- Institute of Tourism and Sustainable Economic Development, Universidad de Las Palmas de Gran Canaria, Engelina du Plessis --- North-West University, South AfricaThe study aims to analyse how framing (recommending versus complaining) affects the measurement of destination loyalty. It focuses on international tourists who visited South Africa, and evaluated loyalty through the two framings. The study tests whether loyalty can be measured... -
Phosphorus sorption kinetics in calcareous soils of selected arid and semi-arid toposequences and its relationship with plant growth
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Jafari --- Department of Soil Science, College of Agriculture, Isfahan University of Technology, Iran H. Shariatmadari --- Department of Soil Science, College of Agriculture, Isfahan University of Technology, Iran Y. Rezainejad --- Department of Soil Science, College of Agriculture, Isfahan University of Technology, Iran Sh. Ghalami --- Department of Soil Science, College of Agriculture, Isfahan University of Technology, IranAn array of kinetic equations has been used to describe time-dependent sorption of P by soils. We investigated P sorption kinetics in calcareous soils at upper-, mid-, and lowerslope positions of two arid and two semi-arid landscapes and its relationship... -
How academic stress affects academic performance: A chain-mediated model of sex moderation
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Yunhan Zhang --- Central China Normal University, China Sannyuya Liu --- Central China Normal University, China Liang Zhao --- Central China Normal University, China Zhi Liu --- Central China Normal University, ChinaAcademic stress is a common psychological issue among college students, but the mechanism by which it affects academic performance is not well understood. This study extends existing literature by exploring a chain-mediated model composed of academic stress, learning motivation, depression,... -
Subjective well-being of college students: Developmental trajectories, predictors, and risk for depression
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Xinqiao Liu --- Tianjin University, China Yan Li --- Tianjin University, China Wenjuan Gao --- Institute of Higher Education, Beihang University, ChinaThe study aimed to identify different developmental trajectories of subjective well-being for 2 473 college students from freshman to senior year (female = 47.15%; mean age = 19.6 years, SD = 0.894 years). We further explored the associations between categories... -
Family cohesion and adaptability effects on social anxiety among adolescents: The mediating role of experiential avoidance
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Yakun Ni --- Institute of Applied Psychology, Guangdong University of Finance, China Shiya Zeng --- Institute of Applied Psychology, Guangdong University of Finance, China Yanzhen Xu --- Guangdong Polytechnic Normal University, China Tengfei Guo --- Guangdong Polytechnic Normal University, ChinaWe investigated the effect of family cohesion and adaptability on adolescent social anxiety and explored the mediating effect of experiential avoidance between them. A total of 610 adolescents completed the Family Adaptability and Cohesion Evaluation Scales II, the Acceptance and... -
Academic researchers’ work stress and work engagement: Hindrance stress appraisal mediation and psychological resilience moderation
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Hui Wang --- Xiangtan University, China Yan Li --- Xiangtan University, ChinaWe explored the role of hindrance stress appraisal and psychological resilience in the relationship between work stress and work engagement among academic researchers. Data were collected from academic researchers in China (n = 314; female = 48.7%; professor = 10.8%,... -
How can work improve family life quality? The influence of thriving at work on family role performance and work–family balance satisfaction
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Shaoqing Su --- Northwest Normal University, People’s Republic of China Baoyan Yang --- Northwest Normal University, People’s Republic of China Zhaobiao Zong --- East China Normal University, People’s Republic of China Zhao Zhang --- Lanzhou Modern Vocational College, People’s Republic of ChinaThis study examined how career success related to employees’ family life quality, with interpersonal capitalisation between employees’ work and family life, controlling for employees’ proactive personality. We sampled married employees from Northwest China (n = 154, females = 53.2%, mean... -
Proactive personality and career success of higher education teachers: The mediating effects of job crafting
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Yunsheng Ruan --- School of Economic and Management, Zhoukou Normal University, China Zibin Cao --- School of Economic and Management, Zhoukou Normal University, China Chao Han --- School of Economic and Management, Zhoukou Normal University, China Qianlu Sun --- School of Economic and Management, Zhoukou Normal University, ChinaWe investigated the role of job crafting (task, cognitive, and environmental) in the relationship between proactive personality and career success among teachers. Participants were 326 higher education teachers (female = 60.4%; senior title = 20.9%; doctoral degree = 22.1%) from... -
Future work self and career calling in vocational education students: Workplace learning as a mediator and mentoring as a moderator
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Bin Liu --- Northeast Normal University, China Chunna Hou --- Northeast Normal University, ChinaWe explored the role of workplace learning and mentoring in the relationship between future work self and career calling among students. The nationwide sample comprised 741 Science and Engineering students from six higher vocational colleges in China (female = 46.56%;... -
Gratitude to nature and pro-environmental behaviour: A moderated mediated model
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Xiaoyu Li --- Inner Mongolia Normal University, China Xindi Kong --- Inner Mongolia Normal University, China Hongyu Liang --- Inner Mongolia Normal University, China Yifan Wang --- Inner Mongolia Normal University, ChinaWe examined the relationship between trait gratitude to nature and pro-environmental behaviours, and the roles of anthropomorphism and connectedness to nature within this relationship. University students (n = 966; female = 47.09%; mean age = 20.75 years, SD = 1.42... -
An investigation into the innovation-economic growth nexus in Mauritius
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Harris Neeliah --- Independent Researcher, Mauritius Boopen Seetanah --- University of Mauritius, Mauritius Lomendra Vencataya --- University of Mauritius, MauritiusThis paper extends the existing strand of research, delving into the link between innovation and economic growth for the small island developing state of Mauritius. The innovation-growth relationship is analyzed within a multivariate endogenous growth model, spanning the period 1970... -
Modelling the perception of banking customers on mobile technology adoption in a developing economy
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Emmanuel Asafo-Adjei --- Global Development Institute, School of Environment, Education and Development, The University of Manchester, UK Anokye M. Adam --- Department of Finance, School of Business, University of Cape Coast, Ghana Peterson Owusu Junior --- Department of Finance, School of Business, University of Cape Coast, GhanaDespite the numerous risks and security dangers associated with mobile banking, an increasing number of banks in developing economies are appreciating the merits of mobile technology. Hence, we investigated customers’ perception of mobile technology adoption (MTA) in the banking industry,... -
Identification of factors influencing electricity consumption in Yaoundé City, Cameroon
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Léonce Tokam --- University of Lomé, Togo Sanoussi S. Ouro-Djobo --- University of Lomé, TogoThis study explores the factors influencing household electricity consumption in Yaoundé, Cameroon, where energy poverty, frequent power cuts and high tariffs pose major challenges to ensuring reliable, affordable and permanent access to electricity for populations, given the energy potential the... -
Establishment of determinants to influence community acceptance towards water reuse in India
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Kirti Goyal --- Lovely Professional University, India Arun Kumar --- Indian Institute of Technology, IndiaWorldwide, rising water scarcity calls for alternatives to supplement the water supplies. Water reuse is an emerging source, ensuring water safety and environmental sustainability, but its growth is hindered due to sparse public acceptance. In this study, a social survey... -
Age and growth of the invasive bluegill Lepomis macrochirus (Rafinesque, 1810) from the Howison’s Poort Dam, Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PM Ndaleni --- South African Institute for Aquatic Biodiversity, South Africa L Mofu --- South African Institute for Aquatic Biodiversity, South AfricaThe present study assessed the age and growth of bluegill, Lepomis macrochirus (Rafinesque, 1810) from Howison’s Poort Dam, Eastern Cape. Precision between readers and structures (burnt and unburnt) of otoliths were estimated, and the aging error was determined by the... -
Filling in the gaps: Distribution of the puff adder Bitis arietans (Merrem, 1820) in central South Africa and Lesotho – an investigation using mainly social media records and species distribution modelling
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Cora S Stobie --- National Museum, South Africa Michael F Bates --- National Museum, South AfricaThe puff adder (Bitis arietans) is widely distributed in Africa and south-western Arabia. Most published records for central South Africa and Lesotho are from surveys undertaken nearly 50 years ago, and although a large part of this area is considered... -
Mapping suitable habitat for Hooded Vultures Necrosyrtes monachus in one of the last West African strongholds for the species, The Gambia
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Michael Bode Agunbiade --- Brandenburg University of Technology Cottbus-Sefftenberg, Germany Jallow Mawdo --- Abuko Nature Reserve Headquarters, The Gambia Fagimba Camara --- West African Bird Study Association, Abuko Nature Reserve Headquarters, The Gambia Chefor Fotang --- Brandenburg University of Technology Cottbus-Sefftenberg, Germany Elvis Tangwa --- Palacky University (UP), Czech Republic Olayinka Amos Oladosu --- Brandenburg University of Technology Cottbus-Sefftenberg, Germany Luc Roscelin Dongmo Tédonzong --- Centre for Research and Conservation (CRC), Royal Zoological Society of Antwerp (RZSA), Belgium Yisa Ginath Yuh --- Planning and Environment, University of Concordia, Canada Darcy Ogada --- The Peregrine Fund, United States Klaus Birkhofer --- Brandenburg University of Technology Cottbus-Sefftenberg, GermanyHooded Vultures Necrosyrtes monachus are Critically Endangered, with numbers decreasing due to illegal poisoning, hunting for belief-based use and food, and habitat loss. In The Gambia, human activities currently benefit commensalism between humans and Hooded Vultures, as these birds primarily... -
Integrating rainfall data into site-specific modelling to improve forest productivity estimation of eucalypt hybrid species in coastal Zululand, South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Morries Chauke --- School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, South Africa Henry Mwambi --- School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, South Africa Antonio C Ferraz-Filho --- Federal University of Piauí, BrazilThis study aimed to develop a dynamic dominant height model and explore the effects of rainfall on the growth dynamics of Eucalyptus grandis × Eucalyptus urophylla. This species is grown for wood production in South Africa, and accurately estimating site... -
A shelf-scale assessment of GLORYS and BRAN ocean reanalysis model outputs for the southern Benguela Upwelling System
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AM Kupczyk --- Fisheries and the Environment (DFFE), South Africa T Lamont --- Fisheries and the Environment (DFFE), South Africa I Halo --- Fisheries and the Environment (DFFE), South Africa CS Russo --- Fisheries and the Environment (DFFE), South Africa T Rixen --- Institute for Geology, Universität Hamburg, Germany N Lahajnar --- Institute for Geology, Universität Hamburg, GermanyThe Benguela Upwelling System, with its high variability and productivity, is challenging to monitor owing to limited in situ ocean observations. Researchers therefore often use ocean reanalysis products to simulate oceanographic conditions. We evaluated the performance of the GLORYS and... -
HIV incidence and prevalence projections for Zimbabwe: Findings from five mathematical models
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Isaac Taramusi --- UNAIDS UCO Zimbabwe, Zimbabwe John Stover --- , United States of America Robert Glaubius --- , United States of America Tsitsi Apollo --- Ministry of Health and Child Care, Zimbabwe Getrude Ncube --- Ministry of Health and Child Care, Zimbabwe Owen Mugurungi --- Ministry of Health and Child Care, Zimbabwe Ngwarai Sithole --- Ministry of Health and Child Care, Zimbabwe Loveleen Bansi-Matharu --- Institute for Global Health, University College London, United Kingdom Jenny Smith --- Institute for Global Health, University College London, United Kingdom Andrew Phillips --- Institute for Global Health, University College London, United Kingdom Valentina Cambiano --- Institute for Global Health, University College London, United Kingdom Daniel T Citron --- New York University Grossman School of Medicine, United States of America Anna Bershteyn --- New York University Grossman School of Medicine, United States of America Debra ten Brink --- Burnet Institute, Australia Rowan Martin-Hughes --- Burnet Institute, Australia Michael Pickles --- Medical Research Council Centre for Global Infectious Disease Analysis, Imperial College London, United Kingdom Paul Revill --- University of York, United Kingdom Amon Mpofu --- National AIDS Council of Zimbabwe, Zimbabwe Jeffrey Imai-Eaton --- Chan School of Public Health, Center for Communicable Diseases Dynamics, Harvard University, United States of America Richard Makurumidze --- Faculty of Medicine and Health Sciences, University of Zimbabwe, Zimbabwe Simbarashe Rusakaniko --- Faculty of Medicine and Health Sciences, University of Zimbabwe, ZimbabweIntroduction: Understanding how HIV epidemics are likely to behave in the future is key to informing HIV response strategies in low-income countries. Up-to-date HIV epidemiological estimates are important for policy decision- making, but surveillance data can be out of date... -
The roadblocks to progress: A comprehensive study on the relationship between regional institutional quality and firms’ innovation of sub-Saharan African nations
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Abel Dula Wedajo --- University of Sanya, People’s Republic of China Xiao Huilin --- University of International Business and Economics (UIBE), People’s Republic of ChinaThis study examines the impact of regional institutional quality (level two) on firm-level innovation (level one) in Sub-Saharan Africa (SSA), where cultural and institutional diversity challenges frameworks derived from homogeneous contexts. Analyzing 7,578 firms across Ethiopia, Kenya, Rwanda, Tanzania, Uganda,... -
Determinants of adoption and intensity of mechanization in Ethiopia: Evidence from Arsi Zone
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Gizachew Mengesha Abebe --- Bahir Dar University, Ethiopia Wondaferahu Mulugeta Demissie --- Ethiopian Civil Service University (ECSU), Ethiopia Markose Chekol Zewdie --- Bahir Dar University, EthiopiaMechanization has been recognized as a key thematic area by the Ethiopian Agricultural Research Institute for the period 2018–2030; however, research on its adoption determinants remains limited. This study examines the factors influencing the adoption and intensity of mechanization, focusing... -
Assessment of compliance level with the International Labor Organization child labour utilization regulation: Evidence from cassava farmers in Osogbo ADP Zone, Osun State, Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Lateef Olatunbosun Jimoh --- Osun State University, Nigeria Timothy Olusola Agboola --- Osun State University, Nigeria Olaide Kamila Akintunde --- Osun State University, Nigeria Kaothar Modupe Idris-Adeniyi --- Osun State University, Nigeria Francis Oluwadamilare Ajayi --- Osun State University, Nigeria Festus Adelekan Oyeniyi --- Osun State University, NigeriaInvestigating the compliance level of International Labor Organization (ILO) regulation on child labour use among cassava farming households in Osogbo ADP Zone, Osun State, Nigeria, the study determines the factors influencing child labour usage among cassava farmers in the study... -
Proxy variables to represent the productive capacity in a forest growth and yield model for eucalypt hybrid plantations in north-eastern Bahia, Brazil
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Mariana Futia Taquetti --- Universidade Federal de Viçosa, Brazil Carlos Pedro Boechat Soares --- Universidade Federal de Viçosa, Brazil Helio Garcia Leite --- Universidade Federal de Viçosa, Brazil Álvaro Augusto Vieira Soares --- Universidade Federal de Uberlândia, Instituto de Ciências Agrárias, Brazil Gilson Fernandes da Silva --- Universidade Federal do Espírito Santo, BrazilThe present study aimed to evaluate proxy variables to represent the productive capacity of the sites in a forest growth and yield model for plantations of Eucalyptus urophylla × Eucalyptus grandis hybrid, considering them in a linear and a linear... -
Species-specific wood volume growth models outperform unified model across eucalypt species
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Emanuel Ferrari do Nascimento --- Universidade Federal de Viçosa (UFV), Brazil João Amaro Ferreira Vieira Netto --- Universidade Federal de Viçosa (UFV), Brazil Marco Antônio Peixoto --- University of Florida, USA Larissa Pereira Ribeiro Teodoro --- Universidade Federal do Mato Grosso do Sul (UFMS), Brazil Paulo Eduardo Teodoro --- Universidade Federal do Mato Grosso do Sul (UFMS), Brazil Leonardo Lopes Bhering --- Universidade Federal de Viçosa (UFV), BrazilForest ecosystems play an essential role in maintaining biodiversity and mitigating global warming. Intensively managed forest plantations represent a major raw material source for pulp, timber and paper industries. The objective of this study was to apply the model identity... -
The impact of entrepreneurial cognition on opportunity-capitalizing capabilities and business model change: Evidence from Egypt
Item type: Journal Article • Journal: Africa Journal of Management • Authors: Nancy Bouchra Hanna --- Amity University Dubai, UAE Erich Zahn --- University of Stuttgart, Germany Hadia H. Abdel Aziz --- Universities of Canada, Egypt Christine Madonna Kirkland --- Western Carolina University, USA R. Michael Holmes --- Florida State University, USAThis study advances the upper echelons literature by examining the (a) cognitive microfoundations of business model change and (b) intervening organizational mechanisms that help to explain the influence of strategic leaders on firm outcomes. We develop our theory by considering... -
Text-mining approach with Black–Litterman model: A case study of Armenian pension funds
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Ruben Gevorgyan --- Head of Data Science for Business Master Program at Yerevan State University, Armenia Rita Hovhannisyan --- Yerevan State University, ArmeniaPension fund managers face challenges in acquiring, analysing, and synthesising external information to make informed investment decisions. Text-mining and sentiment analysis can aid fund managers integrate contrasting news, financial data, and market speculation into their decision rubric. Considering Armenia pension... -
Fintech predictive modelling using machine learning: An empirical investigation of South Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Abraham Emuron --- Tshwane University of Technology, South Africa Abraham Dimitri Kapim Kenfack --- Tshwane University of Technology, South Africa Mandla Msimanga --- Tshwane University of Technology, South AfricaA significant change in the financial industry has been brought about by technological advancements and shifting consumer behaviour. The result has been the emergence of fintech. Consequently, this paper constructs predictive models to forecast the adoption of fintech in South... -
Measuring successful business models in Ethiopian technology business: A PLS-SEM approach
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Abebe Shimelis --- School of Mechanical and Industrial Engineering, Addis Ababa Institute of Technology, Ethiopia Birhanu Beshah --- School of Mechanical and Industrial Engineering, Addis Ababa Institute of Technology, Ethiopia Ermias Tesfaye --- School of Mechanical and Industrial Engineering, Addis Ababa Institute of Technology, EthiopiaThe development of successful business models is crucial for sustaining innovative technology firms; however, measuring business model success remains challenging due to varying economic dynamics. This study addresses this gap by developing and testing a framework to assess the success... -
Sediment dynamics in the Roman Rock area of False Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Terhorst --- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia M de Vos --- University of Connecticut, United States C Rautenbach --- Waikato Regional Council, New ZealandThis study investigated sediment dynamics in the Roman Rock area of False Bay, South Africa, by integrating sediment grain size data with hydrodynamic and wave modelling. We examined two significant events: a long-period southwesterly swell in 2008, and a prolonged... -
Factors driving pre-exposure prophylaxis uptake among students at six Gauteng province universities: An application of Pender’s Health Promotion Model
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Paul Potsane --- University of Johannesburg, South Africa Charlene Downing --- University of Johannesburg, South Africa Patrick Ndayizigamiye --- College of Business & Economics, University of Johannesburg, South AfricaBackground: South Africa has the world’s highest HIV prevalence rate (12.7%), with university students disproportionately affected. While HIV Pre-Exposure Prophylaxis (PrEP) is an effective preventive measure for high-risk individuals, its uptake among university students remains low, which hinders progress toward... -
A reduced-parameter predator–prey model of soil formation from bedrock and biomass
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Animesh Samanta --- The Neotia University, India Priyanka Mandal --- The Neotia University, India Ayan Chatterjee --- The Neotia University, IndiaSoil–bedrock interaction on hillslopes is not well-studied, though it's affected by many physical and chemical factors. The aim of the present mathematical modelling study is to construct a model for soil formation utilising ordinary differential equations, all while reducing the... -
The phonological structure of South African Sign Language (SASL) toponyms
Item type: Journal Article • Journal: South African Journal of African Languages • Authors: Patrick Sibanda --- University of Free State, South Africa Sarah Siyavoshi --- University of Free State, South AfricaThis study is framed within the prosodic model, and sought to analyse the phonological parameters of handshape, location, palm orientation, movement, and non-manual markers in the formation of SASL toponyms. Place name signs are a cultural and sociolinguistic marker used... -
Measuring adaptive decision making in livestock grazing systems
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Jenna M Likins --- Department of Rangeland, Wildlife and Fisheries Management, Texas A&M University, College Station, USA Jason E Sawyer --- East Foundation, USA Urs P Kreuter --- Department of Ecology and Conservation Biology, Texas A&M University, College Station, USAAdaptive management is essential for managing complex grazing systems under environmental uncertainty. However, its implementation in grazing operations is inconsistently defined and measured. This study addresses this limitation by developing and validating the Adaptive Management Index (AMI), a standardised instrument... -
Life-history traits of the false jacopever Sebastes capensis (Scorpaenidae: Sebastinae) in South African waters
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Mohamed --- Department of Biological Sciences, University of Cape Town, South Africa CG Attwood --- Department of Biological Sciences, University of Cape Town, South AfricaThe genus Sebastes (rockfishes) of family Scorpaenidae (scorpionfishes) contains over 110 species, of which the false jacopever Sebastes capensis is the only one found in South African waters. Although it is a commonly caught linefish along the west coast of... -
Analysis of wave energy distribution in the Gulf of Guinea based on reanalysis data from 1993 to 2019
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: G Dingong --- College of Marine Living Resource Sciences and Management, Shanghai Ocean University, China F Bonou --- International Chair of Physics, Mathematics and Applications, University of Abomey-Calavi, Benin Z Sohou --- International Chair of Physics, Mathematics and Applications, University of Abomey-Calavi, BeninThis study examined the geographical and seasonal distribution of wave parameters (significant height, period, direction) and wave energy in the Gulf of Guinea using MFWAM (Météo-France WAve Model) reanalysis data from 1993 to 2019. The model was validated utilising satellite,... -
On asymptotically almost periodic mild solutions of chemotaxis-fluid systems on bounded domains
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Dam Thi Ngoc Van --- Division of Mathematics, Banking Academy of Vietnam, Vietnam Tran Minh Nguyet --- Department of Mathematics, Thang Long University, Vietnam Pham Truong Xuan --- Thang Long University, VietnamWe study the well-posedness and exponential stability of almost periodic (AP-) and asymptotically almost periodic (AAP-) mild solutions for the chemotaxis-Navier-Stokes systems on a bounded domain Ω ⊂ ℝd (d ⩾ 2) with the smooth boundary. Our strategy is: we... -
Delta-shocks and vacuums as flux-approximation limit of solutions to the Aw-Rascle model with time-dependent source
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Mengqi Cui --- Department of Mathematics, Yunnan Normal University, P.R. China Shuai Fan --- Department of Mathematics, Yunnan Normal University, P.R. China Yu Zhang --- Department of Mathematics, Yunnan Normal University, P.R. ChinaThe flux-approximation limit of solutions to the Aw-Rascle (AR) traffic flow model with time-dependent source is considered. First, the Riemann problem containing flux perturbation and generalized Chaplygin gas (GCG) pressure is solved. Then, it is proved that, as the flux...
