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Aluminium toxicity and induced nutrient disorders involving the uptake and transport of P, K, Ca and Mg in Zea mays L.
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: R.J. Bennet --- Department of Agriculture, C.M. Breen --- Department of Botany, M.V. Fey --- Department of Soil Science and Agrometeorology,Chemical analysis of plant fractions of maize cultivars TX 24 and HL 1 grown in liquid culture containing Al showed that the action of Al was directed at the uptake of Ca and Mg and the transport of P and... -
The aluminium response network in perennial ryegrass (Lolium perenne): II. Water fluxes and ion transport
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: R.J. Bennet --- , Republic of South Africa A. Stewart --- , New ZealandAluminium toxicity was investigated by analyzing the mineral nutrition and water-use characteristics of hydroponically-grown plants differing in tolerance to Al when subjected to Al (0, 20, 40, 80 μM: pH 4.5) for 28 days. Both lines reacted to Al by... -
The effect of clone type and method of transportation on oil yield from vegetative material of Eriocephalus punctulatus
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: L.N. Webber --- Department of Livestock and Pasture Science, Republic of South Africa M.L. Magwa --- Electron Microscope Unit, J. van Staden --- Department of Botany, University of Natal Pietermaritzburg, Republic of South AfricaEriocephalus punctulatus, also known as, ‘Kapok Bos’, belongs to the Asteraceae family. It is an attractively scented woody shrub, that reaches a height of about one metre. It produces a highly priced essential oil with a dark blue colour and... -
PRELIMINARY RESULTS ON THE UPTAKE AND RELEASE OF 32P BY POTAMOGETON PECTINATUS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.H. Swanepoel --- , South Africa J.F. Vermaak --- , South AfricaThe absorption and release of 32PO4, by Potamogeton pectinatus L during winter was investigated using a partitioned container in which the roots were separated from the stems and leaves. 32PO4 is absorbed by the roots as well as the stems... -
COMPOSITION, ABUNDANCE AND SEASONALITY OF LARVAL FISH IN RICHARDS BAY HARBOUR, KWAZULU-NATAL, SOUTH AFRICA
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: S. A. Harris --- , , South Africa D. P. Cyrus --- , , South AfricaThe present study examined the composition, abundance and seasonality of fish larvae occurring in Richards Bay Harbour, over an 18-month period from June 1991 to November 1992. Ichthyoplankton samples were collected every six weeks at top, mid and bottom depths... -
Provincial road condition and round wood timber transport in South Africa
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: StephenJ. Nicholls ReinoE. Pulkki PierreA. AckermanThe context of the study is the concern over declining provincial road conditions due to insufficient government funding for road maintenance. The roads are used by a wide variety of commercial and private interests that contribute a broad range of... -
The Transportability and Utility of Cognitive Therapy in South African Contexts: A Review
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Charles Young --- Rhodes University, South AfricaCognitive therapy could be more widely promoted in South Africa given the great disparity between the need and provision of psychological therapies. Three possible objections to the promotion of cognitive therapy are considered: uncertainty surrounding the effectiveness of cognitive therapy... -
Perceptions of Staffriding in Post-Apartheid South Africa: The Lethal Thrill of Speed or the Masculine Performance of a Painful Past?
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Dimakatso Sedite --- University of South Africa, Brett Bowman --- University of the Witwatersrand, Lindsay Clowes --- University of the Western Cape,Staffriding, or train surfing, involves taking life threatening physical risks by moving around the outside of moving trains. In aiming to better understand this risky practice, this small scale qualitative study used three semi-structured interviews and three focus discussions to... -
Group invariant solutions for two dimensional solute transport under realistic water flows
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: R.J. Moitsheki P. Broadbridge M.P. EdwardsWe consider a form of the solute transport equation in streamline coordinates. Symmetry analysis of the equation for solute transport with realistic water flows, result in a number of admitted nontrival classical Lie point symmetries. Reduction by one of the... -
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... -
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... -
Can the End Products of Anaerobic Metabolism, Tauropine and D-lactate, Be Used As Metabolic Stress Indicators During Transport of Live South African Abalone Haliotis Midae?
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S. O'Omolo G. Gäde P. A. Cook A. C. BrownThis study was undertaken to investigate whether the accumulation of end products of anaerobic metabolism can be used as an early indicator of deteriorating conditions during transport of live abalone Haliotis midae. A first series of experiments revealed that the... -
Adult Movement and Larval Dispersal of Argyrozona Argyrozona (Pisces: Sparidae) from a Temperate Marine Protected Area
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S. L. Brouwer M. H. Griffiths M. J. RobertsAdult emigration and larval dispersal of carpenter Argyrozona argyrozona from the Tsitsikamma National Park (TNP), South Africa, were investigated using mark-recapture data and Acoustic Doppler Current Profiler measurements of currents. Tagging data showed that adult carpenter were mainly resident, with... -
“Shorthaul” pulpwood transport in South Africa. A network analysis case study
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: Pierre A. Ackerman --- Forest Engineering, Faculty of Agricultural and Forestry Sciences, South Africa Reino E. Pulkki --- Faculty of Forestry and the Forest Environment, CanadaShorthaul transport, also known as secondary intermediate transport (SIT), is a feature of pulpwood transport in South Africa. SIT is an additional transport phase within traditional secondary transport. It originates at roadside landing or depot and terminates at another depot,... -
Evidence of carbon transport between shelf and slope waters in the Benguela upwelling system
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Swart HN Waldron L HutchingsThe world ocean is pivotal in the global carbon cycle and, subsequent to anthropogenic loading of the atmosphere with CO2, its ability to sequestrate photosynthetically-fixed carbon is important with respect to our ability to predict climate change. A study of... -
Short-term variability in alongshore winds and temperature off Swakopmund, Namibia, during a non-upwelling event in 1998–1999
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CH Bartholomae E HagenSwakopmund is a popular coastal resort in Namibia, especially during the summer holiday season when daily sea temperatures can fluctuate several degrees in a short period. Hourly measurements of the near-bottom water temperature were collected off the Swakopmund Jetty to... -
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... -
Modelling of wander ratios, travel speeds and productivity of cable and grapple skidders in softwood sawtimber operations in South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Pierre Ackerman --- Department of Forest and Wood Science, South Africa Reino Pulkki --- Department of Forest and Wood Science, South Africa Elizabeth Gleasure --- Department of Forest and Wood Science, South AfricaThe objective of this study was to develop predictive models for cable and grapple skidder wander ratios, travel speeds (loaded and unloaded), and productivity in softwood roundwood sawtimber harvesting operations. For field data collection, the study utilised on-board computing systems... -
“Dwelling-in-Travel”: Of Ships, Trains and Planes in M.G. Vassanji's Fiction
Item type: Journal Article • Journal: Eastern African Literary and Cultural Studies • Authors: Tina Steiner --- English Department, South AfricaM.G. Vassanji's prominent thematic concerns of movement, diaspora, memory, and the formation of migrant subjectivities can be traced and apprehended by paying close attention to the intersecting paths across the Indian Ocean, across railroad tracks into various East African territories... -
Softwood sawlog secondary transport travel speed prediction for the South African forestry industry
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Pierre A Ackerman --- Department of Forest and Wood Science, South Africa Reino E Pulkki --- Department of Forest and Wood Science, South Africa Elizabeth Gleasure --- Department of Forest and Wood Science, South AfricaThe objective of this study was to develop a predictive model for travel speed of softwood sawlog timber transport (STT) vehicles over a range of forest and provincial roads of varying condition for the South African forestry industry. Data was... -
The California bearing ratio (CBR) of some mechanically stabilised laterite sub-base soils along the Ibadan-Oyo Road, Southwestern Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: P.A. Fasanmade --- Civil Engineering Department, Nigeria G.O. Adeyemi --- Geology Department, Nigeria E.O. Eze --- Civil Engineering Department, NigeriaMechanical stabilisation by mixing one lateritic soil with another is not a popular subject of research, hence this study. Samples were taken from two locations along the Ibadan-Oyo Road in Southwestern Nigeria. The study focused on determining the California bearing... -
Stability and enhancement analysis of a modelled self-balancing verticalized mobility aid using optimal control techniques
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Roger van Rensburg --- Department of Electrical Engineering, South-Africa Nico Steyn --- Department of Electrical Engineering, South-Africa Lambert Trénoras --- Laboratoire d’Ingénierie des Systèmes de Versailles, France Yskandar Hamam --- Department of Electrical Engineering, South-Africa Eric Monacelli --- Laboratoire d’Ingénierie des Systèmes de Versailles, FranceThis research comprises an analytical study of the Gyrolift, a new type of robotic wheelchair mobility aid adapted from the Segway self-balancing human transporter, and suggests additional contributions to its development. The Gyrolift is equipped with an agility module that... -
Robust optimisation of forest transportation networks: a case study
Item type: Journal Article • Journal: Southern Hemisphere Forestry Journal • Authors: G Murphy HC StanderForest transportation costs are the major cost component for many forest product supply chains. In order to minimise these costs, many organisations have turned to optimisation models to guide decisions that are extremely complex in nature. These models generally assume... -
Evaluation of the Copan eSwab®, a liquid-based microbiology transport system, for the preservation of Neisseria gonorrhoeae at different temperatures
Item type: Journal Article • Journal: Southern African Journal of Infectious Diseases • Authors: Lindy Gumede --- National Institute for Communicable Diseases, South Africa Frans Radebe --- National Institute for Communicable Diseases, South Africa Duduzile Nhlapo --- National Institute for Communicable Diseases, South Africa Venessa Maseko --- National Institute for Communicable Diseases, South Africa Tendesayi Kufa-Chakezha --- National Institute for Communicable Diseases, South Africa Ranmini Kularatne --- National Institute for Communicable Diseases, South AfricaAims and objectives: To evaluate the survival duration of Neisseria gonorrhoeae from male urethral discharge specimens collected using the Copan eSwab® liquid-based microbiology transport system, at both ambient and refrigerator temperatures. -
A South African softwood sawtimber supply chain case study
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Pierre A Ackerman --- Department of Forest and Wood Science, South Africa Elizabeth A van der Merwe --- Department of Forest and Wood Science, South Africa Reino E Pulkki --- Department of Forest and Wood Science, South AfricaSupply chain management principles were analysed by investigating the effects of smaller-scale and incremental interventions in a forest-to-mill value chain on financial returns and forest resource use in an Eastern Cape case study area. Three previous studies provided input by... -
The attitudes of riparian communities to the presence of water hyacinth in the Wouri River Basin, Douala, Cameroon
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SN Kenfack Voukeng --- Department of Zoology and Entomology, South Africa P Weyl --- Department of Zoology and Entomology, South Africa MP Hill --- Department of Zoology and Entomology, South Africa N Chi --- Watershed Task Group Coordinator (WTG), CameroonSince publication of the first record of Eichhornia crassipes in Cameroon in 1997, the weed has become highly invasive in the Wouri River Basin. Between June and September 2014, a socio-economic survey using participatory and qualitative methods was undertaken in... -
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... -
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... -
Intention to use High Speed Rail (HSR) in Ghana: A comparative study
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Frank Ebo Sagoe --- , China Ying Teng --- , China Joy Say --- , China Lawrence Sagoe --- , Ghana Anita Sagoe --- , Ghana Muhammad Hashim Shah --- , ChinaThis exploratory study aimed to examine the intention of people to use High Speed Rail (HSR) in Ghana premised on convenience, traveling time reliability, and transport safety. Participants were a convenience sample of 957 public transportation users (female = 40.6%;... -
Productivity curve models in eucalypt timber forwarding
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Irineu Barros Nunes --- , Brazil Eduardo da Silva Lopes --- , Brazil Millana Bürger Pagnussat --- , Brazil Julio Eduardo Arce --- , BrazilExtraction is the most costly and complicated stage of timber harvest operations. The forwarder’s productive capacity in timber harvesting, from planted forests, is influenced by several operational variables, especially by extraction distance and tree volume. Prior knowledge about the effect... -
Rainfall-driven nutrient loading affects coastal phytoplankton in the southwestern Indian Ocean: a lagoon at Mauritius Island
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Soondur --- , Republic of Mauritius R Boojhawon --- , Republic of Mauritius R Lowe --- , Australia D Kaullysing --- , Republic of Mauritius BE Casareto --- , Japan Y Suzuki --- , Japan R Bhagooli --- , Republic of MauritiusThis study aimed to test the effects of rainfall-driven nutrient loading on the microphytoplankton dynamics in the shallow water at Trou aux Biches lagoon on the northwest coast of Mauritius. Changes in density, diversity and estimated productivity of microphytoplankton were... -
Physiological traits associated with drought tolerance in Moroccan chickpea
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Meriem Tabouktirt --- University Hassan II, Morocco Fatoumata Farida Traore --- University Hassan II, Morocco Sara Fahde --- , Morocco Ayyoub Ammar --- University Hassan II, Morocco Hasnae Choukri --- , Morocco Said Boughribil --- University Hassan II, MoroccoIn a greenhouse experiment conducted in Mohammedia, drought stress responses were evaluated under two treatments (100% and 50% of field capacity; FC) in six Moroccan chickpea varieties: Arifi, Bouchra, Farihane, Moubarak, Rizki, and Zahour. The susceptibility index (SI) clearly differentiated...