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Vegetation response to wagon wheel camp layouts
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: YvetteJ. Stroleny --- Botany Department, Republic of South Africa M.T. Mentis --- Botany Department, Republic of South AfricaWagon wheel camp layouts have been favoured, in some quarters, for rotational grazing due to the economy and convenience of having the camps radially arranged around central facilities. A possible disadvantage of such layouts is the tendency for over‐grazing near... -
Optimisation of transient transformation of a South African spring wheat cultivar with particle bombardment
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: S.M. de Villiers --- , Republic of South Africa Y. Laib --- Centre de Developement des Techniques Nuclear, AlgeriaTransient transformation was optimised for bread wheat, Triticum aestivum L. cv Kariega, using a particle inflow gun constructed at ARC-Roodeplaat. Excised immature embryos, cultured in vitro for 5 to 7 days, were bombarded with pAHC25 and analysed for the presence... -
Evaluation of soilless production systems for small scale production of two Amaranthus species and Swiss chard, Beta vulgaris
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.M. Sedibe --- Dept. of Agronomy, RSA N. J.J. Combrink --- Dept. of Agronomy, RSA E.Y. Reinten --- , South AfricaTo improve the diet of rural families, small scale production of leafy vegetables, as a source of vitamin A and other nutrients should be encouraged. In this study, conducted under controlled environmental conditions (day temperatures in the greenhouse varied between... -
Some properties and expansions associated with the q-digamma function
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Ahmed Salem --- Department of Mathematics, Faculty of Science, Kingdom of Saudi ArabiaThis paper is devoted to derive some properties and expansions associated with the q-digamma function. The Newton series which is consisting of terms of forward difference operator, is established for the q-digamma function. The maltiplication formula of the q-gamma function... -
Hilbert-type inequalities for Hilbert space operators
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Mario Krnić --- Faculty of Electrical Engineering and Computing, CroatiaIn this paper we establish a general form of the Hilbert inequality for positive invertible operators on a Hilbert space. Special emphasis is given to such inequalities with homogeneous kernels. In some general cases the best possible constant factors are... -
Turnover patterns in fish versus macroinvertebrates — implications for conservation planning
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NA Rivers-Moore --- School of Agricultural, Earth and Environmental Sciences, South AfricaSpatial patterns in taxonomic richness and turnover for fish and aquatic macroinvertebrates are compared to assess the relative usefulness of each taxonomic group in mapping biodiversity patterns. Fish and aquatic macroinvertebrate species data for sites down the longitudinal axes of... -
The Structure of Cellulose by Conformational Analysis.
Item type: Journal Article • Journal: South African Forestry Journal • Authors: A. Pizzi --- , N. Eaton --- ,Conformational analysis studies on the tertiary structure of cellobiose and methyl-β-cellobioside were carried out by using calculations of Van der Waals, H-bond, electrostatic and torsional energy interactions between the atoms and groups of the molecules. Energy maps in function of... -
The Structure of Cellulose by Conformational Analysis.
Item type: Journal Article • Journal: South African Forestry Journal • Authors: A. Pizzi --- Council for Scientific and Industrial Research, South Africa N. Eaton --- Council for Scientific and Industrial Research, South AfricaThe Meyer/Misch and related models were found to be the most energetically stable for the crystalline structure of cellulose I. The cellobioside structure is the monomer of cellulose I as structures having cellobiose as monomer have been proven to be... -
Beta-2 microglobulin as a predictor of peripheral arterial disease in diabetes: the effect of estimated glomerular filtration
Item type: Journal Article • Journal: Journal of Endocrinology, Metabolism and Diabetes of South Africa • Authors: P Rheeder --- Epidemiology and Biostatistics Track, School of Health Systems and Public Health, University of Pretoria, L Nel --- Department of Internal Medicine, Faculty of Health Sciences, F Meeuwes --- Medical Research Council Unit for Inflammation and Immunity, Department of Immunology, Faculty of Health Sciences, M Van Schendel --- Department of Internal Medicine, Faculty of Health Sciences, PWA Meyer --- Medical Research Council Unit for Inflammation and Immunity, Department of Immunology, Faculty of Health Sciences,Background: Peripheral arterial disease (PAD) is common in patients with type 2 diabetes mellitus. Its definitive diagnosis requires ultrasound or angiography. Beta-2 microglobulin (β2 microglobulin) has been proposed as a diagnostic marker for PAD. The objective of the study was... -
Varenicline: a new pharmacotherapy for smoking cessation in primary care practice
Item type: Journal Article • Journal: South African Family Practice • Authors: N Robson --- University Malaya, MalaysiaBackground: Cigarette smoking causes significant morbidity and mortality and is a major public health concern worldwide. Primary care doctors are in a unique position that enables them to promote smoking cessation, as smokers are more aware of their health at... -
Beta blockers and their combinations in the management of hypertension
Item type: Journal Article • Journal: South African Family Practice • Authors: JA Ker --- Department of Internal Medicine Faculty of Health Sciences, -
Effect of production site, storage duration, and hot water and molybdenum dips on bioactive compounds with antioxidant properties in lemon flavedo during cold storage
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Nhlanhla Mathaba --- School of Agricultural, Earth and Environmental Sciences, South Africa John P Bower --- School of Agricultural, Earth and Environmental Sciences, South Africa Isa Bertling --- School of Agricultural, Earth and Environmental Sciences, South AfricaCertain bioactive compounds, such as vitamin E (α-tocopherol), vitamin C (ascorbic acid), β-carotene, polyphenols (e.g. flavonoids and flavonones, viz. hesperidin and naringin) have antioxidant properties and their presence in the citrus flavedo plays a significant role in mitigating oxidative stress,... -
Determining input values for a simple parametric model to estimate evaporation from vineyard soils with special reference to clay content and trellis system
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Philip A Myburgh --- Agricultural Research Council Infruitec-Nietvoorbij, South AfricaEstimating soil evaporation (Es) is an important part of modelling vineyard evapotranspiration for irrigation purposes. Furthermore, quantification of possible soil texture and trellis effects is essential. Daily Es from six topsoils packed into lysimeters was measured under grapevines on slanting... -
Effect of conventional and organic orchard floor management practices on enzyme activities and microbial counts in a ‘Cripp's Pink’/M7 apple orchard
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: André H Meyer --- Agricultural Research Council–Infruitec-Nietvoorbij, South Africa John Wooldridge --- Agricultural Research Council–Infruitec-Nietvoorbij, South Africa Joanna F Dames --- Department of Biochemistry and Microbiology, South AfricaOrganic (ORG) production practices are increasingly being used in South African apple orchards. Whether ORG orchard floor management practices differ in their effects on soil enzyme activities and microbial populations from conventional (CON) practices have not been adequately investigated, particularly... -
Some evidence on the stability of beta coefficients on the JSE
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: D C Bowie --- Quantitative Consultant at The WM Company, Scotland D J Bradfield --- Department of Statistical Sciences,Knowledge of beta stability is crucial for projections involving the use of beta coefficients, in particular, in the areas of project evaluation and portfolio design. This paper investigates the issue of beta stability on the JSE. The investigation reveals how... -
Extraordinary items: Accounting and market risk
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: J A Miller --- Emeritus Professor in Accounting and Finance,The market reaction to the recurrent reporting of extraordinary items was tested by calculating and comparing the betas for a portfolio of shares that reported extraordinary items in each of the five years 1990 through 1994 and a control portfolio... -
Market segmentation and the cost of equity of companies listed on the Johannesburg Stock Exchange
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: C Correia --- Department of Accounting, E Uliana --- Department of Accounting,The segmentation between the Resources/Mining and the Financial and Industrial sectors on the Johannesburg stock exchange and the relative historical dominance of the Mining sector in relation to other international markets poses questions about whether the All share data or... -
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... -
A Review of Systematic Risk Estimation on the JSE
Item type: Journal Article • Journal: De Ratione • Authors: D C Bowie --- University of Cape Town, D J Bradfield --- University of Cape Town,This paper reviews some recent developments in the area of beta estimation on the JSE. it turns out that the dual phenomena of extreme thin trading and mild segmentation between the industrial and mining boards on the JSE impact on... -
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... -
A Note on The Estimation of Betas for Single Industry Companies
Item type: Journal Article • Journal: De Ratione • Authors: Colin Firer --- University of the Witwatersrand, Trevor A Thompson --- University of the Witwatersrand,In order to use the Capital Asset Pricing Model to estimate the cost of equity capital for an unquoted firm, it is often necessary to use the “pure-play” technique to obtain a surrogate beta with an appropriate asset structure for... -
Risk on The Johannesburg Stock Exchange
Item type: Journal Article • Journal: De Ratione • Authors: Mike Ward --- Lecturer in Finance and Quantitative Methods Faculty of Management,The Capital Asset Pricing Model (CAPM) provides a parsimonious method for estimating security returns. However, the strong influence of mining shares on the Johannesburg Stock Exchange (JSE) has complicated the use of the CAPM in South Africa and some researchers... -
Anaesthesia for a patient with beta thalassaemia major
Item type: Journal Article • Journal: Southern African Journal of Anaesthesia and Analgesia • Authors: T Kallenbach --- Department of Anaesthesia, South AfricaWhile beta thalassaemia is not a common disorder with an estimated 100 000 severely affected individuals worldwide, improved survival rates and increased global migration means an increased frequency of such patients being seen for various surgeries. The different aspects of this... -
Prevalence of carbapenem resistance genes in Acinetobacter baumannii isolated from clinical specimens obtained from an academic hospital in South Africa
Item type: Journal Article • Journal: Southern African Journal of Epidemiology and Infection • Authors: M.M. Kock --- , A.N. Bellomo --- , N. Storm --- , M.M. Ehlers --- ,Acinetobacter baumannii is an important cause of hospital-acquired infections. The occurrence of carbapenem resistance that is caused by the carbapenem-hydrolysing class Dβ-lactamases and the metallo-β-lactamases (MBLs) limits the range of therapeutic alternatives in treating A. baumannii infections. In this study,... -
NDM-1, novel TEM-205, novel TEM-213 and other extended-spectrum β-lactamases co-expressed in isolates from cystic fibrosis patients from South Africa
Item type: Journal Article • Journal: Southern African Journal of Infectious Diseases • Authors: Nonhlanhla Mhlongo --- Antimicrobial Research Unit, South Africa Sabiha Essack --- Antimicrobial Research Unit, South Africa Usha Govinden --- Antimicrobial Research Unit, South AfricaBackground: β-lactamase-mediated resistance was investigated in isolates from cystic fibrosis (CF) patients attending clinics in the public and private health sectors in Durban, South Africa. -
African leafy vegetables consumed by households in the Limpopo and KwaZulu-Natal provinces in South Africa
Item type: Journal Article • Journal: South African Journal of Clinical Nutrition • Authors: M Faber --- Nutritional Intervention Research Unit, South Africa A Oelofse --- Centre for Nutrition, South Africa Pj Van Jaarsveld --- Nutritional Intervention Research Unit, South Africa Fam Wenhold --- Division of Human Nutrition, Faculty of Health Sciences, South Africa Ws Jansen van Rensburg --- Agricultural Research Council, South AfricaObjectives: The objectives of this study were to determine the availability of, access to and nutrition-related uses of African leafy vegetables in rural and urban households; and to determine the β-carotene content of the dominant African leafy vegetable. -
Environmental health factors associated with diarrhoeal diseases among under-five children in the Sebeta town of Ethiopia
Item type: Journal Article • Journal: Southern African Journal of Infectious Diseases • Authors: AI Mohammed --- Medical and Health Services Department, Ethiopia Li Zungu --- Department of Health Studies, South AfricaThe aim of this study was to assess and explore household environmental health factors associated with the occurrence of diarrhoea experienced by children under five years of age in Sebeta town of Ethiopia. A cross-sectional study, using stratified random sampling... -
How disruptive can Smart Beta be to the South African Active Fund Management Fraternity?
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Jean-Jacques Duyvené de Wit --- Prescient Securities, South Africa Daniel Polakow --- School of Actuarial Science, South AfricaThis research paper explores the theme of Smart Beta and the current state of inefficiency of active fund fee structures in South African domestic equity unit trusts. The emerging understanding is that many of the latent sources of value-add (or... -
The time traveller’s CAPM
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Jordan French --- Faculty of Business Administration, ThailandThis empirical study comprises six emerging market portfolios and five industry replicating portfolios from the USA, using data from 2005 to 2014. The purpose of this study is to test the ability of the ex-ante beta against the ex-post beta... -
Mechanisms of antibiotic resistance in Haemophilus parainfluenzae
Item type: Journal Article • Journal: Southern African Journal of Infectious Diseases • Authors: Regina E. Abotsi --- Antimicrobial Research Unit, School of Health Science, South Africa Usha Govinden --- Antimicrobial Research Unit, School of Health Science, South Africa Sabiha Y. Essack --- Antimicrobial Research Unit, School of Health Science, South AfricaHaemophilus parainfluenzae is part of the HACEK group of fastidious bacteria commonly implicated in endocarditis and bacteremia. Previously considered as a normal respiratory, oral and sometimes genitourinary commensal, it has been recognised as a pathogen that can cause life-threatening infections... -
Horizontal transfer of OXA-23-carbapenemase-producing Acinetobacter species in intensive care units at an academic complex hospital, Durban, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: Southern African Journal of Infectious Diseases • Authors: Khine Swe Swe-Han --- Department of Medical Microbiology, South Africa Melendhran Pillay --- Department of Medical Microbiology, South Africa Desmond Schnugh --- Infection Control Services Laboratory, Department of Clinical Microbiology and Infectious Diseases, South Africa Koleka P Mlisana --- Department of Medical Microbiology, South Africa Kamaldeen Baba --- Department of Medical Microbiology, National Health Laboratory Service, South Africa Manormoney Pillay --- Medical Microbiology and Infection Control, School of Laboratory Medicine & Medical Science, South AfricaIntroduction: Carbapenemase production is an important mechanism of carbapenem resistance in Acinetobacter species. This study investigated the presence of the carbapenem-hydrolysing class D β–lactamase- encoding genes, blaOXA-23 and blaOXA-58, and their association with the spread of multidrug-resistant (MDR) Acinetobacter species... -
The impact of reference-day risk on beta estimation and a proposed solution
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Keshav Sahadev --- Gordon Institute of Business Science, South Africa Michael Ward --- Gordon Institute of Business Science, South Africa Chris Muller --- Gordon Institute of Business Science, South AfricaThe ability to accurately estimate systematic risk (or beta) when reference-day risk is considered, is an ineluctable requirement for all applications of the capital asset pricing model (CAPM). -
Can non-momentum factor premiums explain the momentum anomaly on the JSE? An in-depth portfolio attribution analysis
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Daniel Page --- Finance Division, School of Economic & Business Sciences, South Africa Christo Auret --- Finance Division, School of Economic & Business Sciences, South AfricaSouth African literature related to the momentum anomaly is generally limited to the exploration of momentum on a univariate and at most a bivariate basis, such as in combination with value (Fraser & Page, 2000) or liquidity (Page, Britten, &... -
The inflation-hedging ability of individual shares: Evidence from the Johannesburg Stock Exchange (JSE)
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Johannes Hendrik van Rooyen --- Department of Business Management, South Africa Daniel Lee Jones --- Department of Business Management, South AfricaThe erosion of purchasing power due to inflation is a source of concern for investors who invest in stocks over long investment horizons. -
Expected option returns during the post-GFC era
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Cheng Yan --- , PRC Xiaoli Wu --- , UKWe investigate whether the option implied volatility predicts the future realised volatility of the underlying securities and whether volatility risk factors exploited from options are pricing factors. Our sample includes six popular stock indices such as the S&P 500 and... -
Soil β-glucosidase activity, organic carbon and nutrients in plant tissue in response to cover crop species and management practices
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Adewole T Adetunji --- , South Africa Bongani Ncube --- , South Africa Andre H Meyer --- , South Africa Reckson Mulidzi --- , South Africa Francis B Lewu --- , South AfricaCover crop (CC) management can be improved to enhance carbon storage, microbial activity and fertility in agricultural soils. This study assessed the immediate effect of living CCs and residues, two termination stages (vegetative and flowering) and two termination methods (slash... -
Small-minus-big predicts betting-against-beta: Implications for international equity allocation and market timing
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Adam Zaremba --- , PolandWe demonstrate a strong relationship between short-term small-firm premium and future low-beta anomaly performance. Rises (declines) in small-firm prices temporarily improve (deteriorate) funding conditions, benefiting (impairing) the short-run returns on the low-beta strategy. To investigate this phenomenon, we examine returns... -
Longitudinal species turnover rates are predictable and should guide location of sampling sites for South African river surveys to assess aquatic biodiversity
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NA Rivers-Moore --- , South Africa FC de Moor --- , South AfricaRepresentative samples of biota collected relative to environmental gradients are important for measuring present distributions and predicting shifts in distribution of taxa in response to climate change or reduced river connectivity. Based on river ecology theory and established measures of... -
Facing challenges and drawing strength from adversity: Lived experiences of Tibetan refugee youth in exile in India
Item type: Journal Article • Journal: Indo-Pacific Journal of Phenomenology • Authors: Kiran Dolly Sapam --- , India Parisha Jijina --- , IndiaThe current study is a qualitative investigation aimed at exploring the lived experiences of Tibetan youth who had escaped to India as unaccompanied minors and since then have been living as refugees in India without their parents. The study attempts... -
An allele-specific PCR assay for detection of mutations that confer benzimidazole resistance and zoxamide sensitivity in Phyllosticta citricarpa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Beatrix Coetzee --- Stellenbosch University, South Africa Elma Carstens --- Citrus Research International (Pty) Ltd, South Africa Gerhardus C Schutte --- Avima (Pty) Ltd, South Africa Elaine Basson --- Citrus Research International (Pty) Ltd, South Africa Mia J Groeneveld --- Stellenbosch University, South Africa Tankiso Mpholo --- Land Reform and Rural Development, South Africa Providence Moyo --- Citrus Research International (Pty) Ltd, South Africa Jessica C Winn --- Stellenbosch University, South Africa Paul H Fourie --- Citrus Research International (Pty) Ltd, South Africa Aletta E Bester van der Merwe --- Stellenbosch University, South AfricaPhyllosticta citricarpa is the causative agent of citrus black spot (CBS), a cosmetic fungal disease that has been reported in most of the citrus-growing regions of the world. The occurrence of CBS in orchards is predominantly controlled by the application... -
Bioprospecting for active compounds: impact of milling, extract fractions and freeze-drying on targeted terpene compounds of Helichrysum odoratissimum (L.) Sweet
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Neliswa A. Matrose --- Agricultural Research Council (ARC) Infruitec-Nietvoorbij, South Africa Zinash A. Belay --- Agricultural Research Council (ARC) Infruitec-Nietvoorbij, South Africa Obikeze Kenechukwu --- University of the Western Cape, South Africa Lucky Mokwena --- Stellenbosch University, South Africa Oluwafemi James Caleb --- Stellenbosch University, South AfricaThis study investigated the effect of processing and freeze-drying on targeted volatile compounds (terpenes) of Helichrysum odoratissimum (L.) Sweet. Air-dried plant material was processed to obtain: (i) roughly ground leaves and stems (RGMHO); (ii) finely ground leaves and stems (FGMHO);... -
Conformally related invariant (α, β)-metrics on homogeneous spaces
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Azar Fatahi --- University of Isfahan, Iran Masoumeh Hosseini --- University of Isfahan, Iran Hamid Reza Salimi Moghaddam --- University of Isfahan, IranIn this paper, we give the flag curvature formula of general (α, β)-metrics of Berwald type. We study conformally related (α, β)-metrics, especially general (α, β)-metrics that are conformally related to invariant (α, β)-metrics. Also, a necessary and sufficient condition... -
Efficacy of immunosuppression in preserving beta cell function and reducing insulin requirements in Type 1 diabetes mellitus: a comprehensive review
Item type: Journal Article • Journal: Journal of Endocrinology, Metabolism and Diabetes of South Africa • Authors: S Pillay --- University of KwaZulu-Natal, South Africa A Pillay --- DRAM Consulting, South Africa A Kalhan --- Royal Glamorgan Hospital, UK -
Taylor theory in quantum calculus: a general approach
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Enas M. Shehata --- Menoufia University, Egypt Rasha M. El Zafarani --- Ain Shams University, EgyptLet the function β be strictly increasing and continuous on an interval I ⊂ ℝ. The β-difference operator is defined by Dβ f (t) = (f(β(t)) − f(t)/(β(t) – t), where t ≠ β(t), and Dβ f (t) = f′... -
Adaptive Beta Shrinkage estimation of covariance matrices
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Henri Staal --- Department of Statistics and Actuarial Science, Stellenbosch University, South Africa Emlyn Flint --- Peresec, South AfricaAccurate estimation of the covariance matrix is essential for mean-variance portfolio optimisation, yet the sample covariance matrix is a notoriously noisy estimate, especially in high dimensions. Contemporary shrinkage methods attempt to mitigate this noise but often retain significant estimation error...