Search
Search results for
We found
116 results for you
-
Fisiologiese blaarabnormaliteite en bolopbrengs by katoen (Gossypium hirsutum L.) soos deur kalium-, kalsium- en boorvoeding beïnvloed
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N. J.J. Combrink --- Navorsingsinstituut vir Tabak en Katoen,Physiological leaf abnormalities and boll yield of cotton (Gossypium hirsutum L.) as affected by potassium, calcium and boron nutrition. A pot trial with a sand medium and two levels each of K, Ca and B nutrition, factorially arranged, was carried... -
Nitrogen fertilization of tea: Effect of tea leaf plucking criteria on chlorophyll and quality parameters
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: L.J. van Lelyveld --- , Republic of South Africa Connie Fraser --- , Republic of South Africa B.L. Smith --- , Republic of South Africa G. Visser --- , Republic of South AfricaThe purpose of this investigation was to establish the possible effect of plucking criteria on the quality of black tea produced with different levels of nitrogen fertilization. Increases in leaf age (norms) resulted in increased total chlorophyll in fresh green... -
The influence of varying P concentrations on the yield and abnormalities of lettuce leaves
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.S. Claassens --- Department of Soil Science and Plant Nutrition, Republic of South AfricaThe effect of varying P concentrations on the growth, yield and development of leaf abnormalities, nutrient content and uptake of other nutrient elements was investigated for lettuce.Three cultivars (Chaparal, Wintercrisp and Robinvale) were studied in sand cultures and soil. The... -
Early post-cleavage stages and abnormalities identified in the embryonic development of chokka squid eggs Loligo vulgaris reynaudii
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: A. Oosthuizen M. J. Roberts W. H. H. SauerSix early, post-cleavage embryonic stages for chokka squid Loligo vulgaris reynaudii eggs that were developed in an aquarium are identified and described, expanding the embryonic stages for this species from 14 to 20. The influence of water temperature on embryonic... -
Re-evaluation of the disc pasture meter calibration for the Kruger National Park, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: N Zambatis PJK Zacharias CD Morris JF DerryDuring routine field application of the disc pasture meter (DPM) in the tall-grass rangeland of the Kruger National Park (KNP), it was noticed that the instrument frequently settles above the bulk of the grass leaf mass, leading to the suspicion... -
Precision and accuracy of sward height distributions
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: C.D. Morris P.J.K. Zacharias J.F. DerryDouble normal distributions can be used to resolve many sward height frequency distributions into two components representing the 'short' (patches) and 'tall' (non∼patches) areas in the sward. The effect of sample size on the precision and accuracy of parameters of... -
Rape and Trauma: A Case Study of a Journey of Recovery
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Maria Papaikonomou --- University of South Africa,This case study presents the results of a counselling intervention with a rape survivor. The woman was twenty-nine years old at the time of the violation. The objective of this study was to explore the dynamics which the woman engaged... -
Normative Indicators for Xhosa Speaking Unskilled Workers on the Wechsler Memory Scale Associate Learning and Visual Reproduction Subtests
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Lauren Fike --- Rhodes University, South Africa Jan Knoetze --- Rhodes University, South Africa Ann Shuttleworth-Edwards --- Rhodes University, South Africa Sarah Radloff --- Rhodes University, South AfricaThis study set out to provide preliminary cross-cultural normative data for educationally disadvantaged Black South African Xhosa individuals (N=33; age range = 18 to 40 years; highest educational level = Grade 11 or Grade 12), on the Associate Learning and... -
Normative Indications for Xhosa Speaking Unskilled Workers on the Trail Making and Stroop Tests
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Karen Andrews --- Department of Psychology, Ann Shuttleworth-Edwards --- Department of Psychology, Sarah Radloff --- Department of Statistics,The aim of this study was to produce preliminary normative indications for the Trail Making Test and the Stroop Test, administered in English, on a non-clinical sample of Black, Xhosa speaking unskilled workers (N = 33), with an educational level... -
The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 1: Tensor Norms
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Diestel Fourie Johan SwartThis paper presents the first of a multi-part series of papers on the metric theory of tensor products according to Grothendieck's "Résumé de la theorie metrique des produits tensoriels topologiques "It contains the basics on tensor norms: a discussion of... -
Natural Alternatives For One Dimensional Median Filtering
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: C.H. Rohwer M. WildFor practical purposes median smoothers have often been considered the basic components for the construction of simple non-linear smoothers for removing impulsive noise before any subsequent linear signal extraction from a sequence. Alternatives exist that are computationally convenient, conceptually simpler... -
Multivalued linear projections
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: R.W. Cross D.L. WilcoxA multivalued linear projection operator P defined on linear space X is a multivalued linear operator which is idempotent and has invariant domain. We show that a multivalued projection can be characterised in terms of a pair of subspaces and... -
The Dual Space of an Asymmetric Normed Linear Space
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: L.M. García-Raffi Romaguera Sanchez-PérezGiven an asymmetric normed linear space (X, q), we construct and study its dual space (X ∗ , q ∗). In particular, we show that (X ∗ , q ∗) is a biBanach semilinear space and prove that (X, q)... -
On the Difference of Orthonormal Polynomials
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: D.G. Kubayi H.P. MasheleWe establish an estimate on the difference of orthonormal polynomials for a general class of exponential weights. -
A Non-topologically Generated Hutton-lowen Uniformizable Space
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Sanjiang Li Dexue ZhangIn this note, it is shown that there exist non-topologically generated spaces which are both Lowen uniformizable and Hutton uniformizable. On the other hand, the FNS-coreflection of the Hutton unit interval I(I) is neither Lowen uniformizable nor Hutton uniformizable. -
The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 5: Injective and Projective Tensor Norms
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Joe Diestel Jan Fourie Johan SwartIn this continuation of our multiseries on Grothendieck's 'Resume', we look at the projective and injective properties of general tensor norms. We also introduce the concepts of left and right injectivity as well as left and right projectivity. -
Riesz Reasonable Cross Norms on Tensor Products of Banach Lattices
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: C.C.A. LabuschagneIf E and F are Banach lattices and α is any reasonable cross norm on E ⊗ F, then there exists a reasonable cross norm | α | on E ⊗ F such that E ⊗ |α | F is... -
Separation of Convex Sets and Best Approximation in Spaces with Asymmetric Norm
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: S. CobzaşThe aim of the present paper is to show that some results in Banach spaces have their analogs in spaces with asymmetric seminorms. A space with asymmetric seminorm is a pair (X, p),where X is a real vector space and... -
Extension of the Dirichlet-Jordan Convergence Criterion for Exponential Weights
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: H.P. MasheleThe well-known Dirichlet-Jordan Criterion for Fourier series states that the trigonometric Fourier series of a 2π periodic function f having bounded variation converges to ½[f(x + 0) + f(x – 0)] for every x and this convergence is uniform on... -
Characterizing the one-sided tensor norms Δ P and T Δ P
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: C.C.A. Labuschagne. The Bochner norms Δ p for 1< p < ∞ on the vector valued L p -spaces are examples of reasonable cross norms which are not tensor norms. Using the order structure of L p (μ), a... -
Compact perturbations and norm attaining operators
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Janice KoverIn 1963, Lindenstrauss showed that for a reflexive space, X, and any Banach space,Y, that the norm attaining operators in L(X, Y) are dense. Recall that a linear operator A is norm attaining if there exists a unit vector x... -
On Frobenius, Mazur, and Gelfand-Mazur theorems on division algebras
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: VictorM. BogdanThe main purpose of this paper is to introduce the reader to the theory of normed division algebras. It is written with a graduate student of mathematics in mind, who only had exposure to Advanced Calculus and to an introduction... -
A note on the M-norm of Chaney-Schaefer
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: StuartF. Cullender CoenraadC.A. LabuschagneWe give elementary proofs of known results concerning lattice and duality properties of the M-norm, introduced by Chaney and Schaefer, on the tensor product of a Banachspace and a Banach lattice. -
On the Radon-Nikodym property and the Lewis-Radon-Nikodym property for a tensor norm
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: S.M. MaepaThe Radon-Nikodym property and the Lewis-Radon-Nikodym property for tensor norms are introduced and discussed. In particular, it is shown that the Hilbertian tensor norm h introduced in [6, Section 3] has the Lewis-Radon-Nikodym property but does not have the Radon-Nikodym... -
Fremlin tensor products of Banach lattices
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Daniele PuglisiWe prove that the Fremlin tensor product of two Banach lattices with the Radon-Nikodym property, with one of them atomic, has the Radon-Nikodym property. -
Perturbations by norm attaining operators
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Janice KoverIn this note, we develop a connection between Fredholm operators and norm attaining operators in the set L(H) of bounded linear operators on a Hilbert space. We use this connection to extend an earlier result about the stability of norm... -
On the Mappings Preserving Equality of 2-Distance
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Wei-Jia Jia* --- School of Mathematics Science, P.R. ChinaIn this paper, we consider 2-isometries, 2-continuous mappings and mappings preserving equality of 2-distance and investigate the relation between the three mappings in linear 2-normed spaces. We prove that if f: E → F is a mapping preserving equality of... -
UG-Differentiability Entails Hahn-Banach
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Marianne Morillon --- ERMIT, Département de Mathématiques et Informatique, FranceDenoting by ACN the countable axiom of choice, we show in ZF+AC N that the dual ball of a uniformly Gâteaux-differentiable normed space is compact in the weak* topology.In ZF, we prove that this dual ball is (closely) convex-compact in... -
On the Ratios of Arc Lengths to Chord Lengths in Real Banach Spaces
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Senlin Wu --- Department of Mathematics, China Chan He --- Department of Mathematics, ChinaTwo new moduli are introduced to study the ratios of arc lengths to chord lengths in Banach spaces. Basic properties of those two moduli and the relation between them are studied. The relation between those two moduli and some geometric... -
The Riesz convergence property on weighted Lorentz spaces and Orlicz-Lorentz spaces
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Hongliang Li --- Department of Mathematics, P.R.ChinaIn this paper, we define new Orlicz-Lorentz spaces . We find the necessary condition and sufficient condition for quasi-normed weighted Lorentz spaces to have Riesz convergence property. Also, we find the similar result for quasi-normed Orlicz-Lorentz... -
The class of b-AM-compact operators
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Belmesnaoui Aqzzouz --- Juridiques et Sociales, Département d'Economie, Morocco Jawad H'Michane --- Département de Mathématiques, MoroccoWe introduce and study a new class of operators that we call b-AM compact operators, and we establish necessary and sufficient conditions on the duality property for this class of operators. As interesting consequences, we obtain some characterizations of discrete... -
Knowledge, attitudes and sexual practices of adolescents with mild retardation, in relation HIV/AIDS
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Naseema Dawood Anil Bhagwanjee Kay Govender Ebrahim ChohanThis study investigates the knowledge, attitudes and sexual practices of adolescents with mild mental retardation (MMR) in relation to HIV/AIDS. Questionnaires were personally administered to a saturation sample of 90 adolescents with MMR drawn from one specialised educational institution in... -
Factors that Affect Municipal Service Delivery in Gauteng and North West Provinces of South Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Solomon Khale --- , South Africa Zeleke Worku --- , South AfricaThis study attempts to identify and quantify factors that affect service delivery by local government counsellors in the Gauteng and North-West provinces. The study is based on a stratified random sample of size n=300 respondents. Both quantitative and qualitative research... -
Abnormal compression wood in Pinus taeda: A review of current knowledge and proposed future strategy
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: F.S. Malan --- Komatiland Forests (Pty) Ltd, Research Division, H.W. Kassier --- South African Forestry Company Ltd,Abnormal compression wood in P. taeda stands was first discovered in the early 1980s. Since then several research projects and surveys have been carried out in order to develop a better understanding of the problem and to try to find... -
Comparing normal, lognormal and Weibull distributions for fitting diameter data from Akashmoni plantations in the north-eastern region of Bangladesh
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: I Kayes --- Department of Forestry and Environmental Science, School of Agriculture and Mineral Sciences, Bangladesh JC Deb --- Department of Forestry and Environmental Science, School of Agriculture and Mineral Sciences, Bangladesh P Comeau --- School of Forest Science and Management, Canada S Das --- Department of Statistics, School of Physical Sciences, BangladeshStatistical probability density functions are widely used to model tree diameter distributions and to describe stand structure. The objective of this study was to compare the performance of normal, logarithmic-normal and three-parameter Weibull distributions for fitting diameter data from Akashmoni... -
Phenotypic plasticity and local adaptation in two extreme populations of Acacia karroo
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: G Bayonne Mboumba D WardPhenotypic plasticity is the effect of growth variability in response to different environmental conditions. Adaptive phenotypic plasticity is more specific; it is the ability of a single genotype to produce an array of phenotypes depending on the environmental extent. We... -
Management of diabetic ketoacidosis
Item type: Journal Article • Journal: Journal of Endocrinology, Metabolism and Diabetes of South Africa • Authors: D Jivan --- Department of Medicine, Division of Endocrinology and Metabolism,Although the mortality of diabetic ketoacidosis (DKA) has decreased substantially in the developed world, high mortality rates still prevail in South Africa, thus making this an important condition to recognise early and manage well. This review discusses the treatment of... -
High prevalence of abnormal liver enzymes in South African patients with type 2 diabetes mellitus attending a diabetes clinic
Item type: Journal Article • Journal: Journal of Endocrinology, Metabolism and Diabetes of South Africa • Authors: IM Paruk --- Department of Diabetes and Endocrinology, FJ Pirie --- Department of Diabetes and Endocrinology, AA Motala --- Department of Diabetes and Endocrinology, BA Kolawole --- Obafemi Awolowo University, NigeriaObjective: To determine the prevalence of liver function test abnormalities in South African black and Indian adult patients with type 2 diabetes mellitus attending a tertiary diabetes clinic. -
Experiences and conceptualizations of sexual debut from the narratives of South African men and women in the context of HIV/AIDS
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Erin Stern --- University of Cape Town, Women's Health Research Unit, South Africa Diane Cooper --- University of Cape Town, Women's Health Research Unit, South AfricaGiven the pivotal role of first sex in the development of sexual and reproductive health (SRH) practices, there is a need for more contextualised and nuanced understandings of young people's early sexual debut experiences. This study used sexual history narratives... -
Black Adults’ Perceptions of Healthy Family Functioning
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Cynthia Zwane --- North-West University (Potchefstroom Campus), South Africa Chris Venter --- North-West University (Potchefstroom Campus), South Africa Q. Michael Temane --- North-West University (Potchefstroom Campus), South Africa Shingairai Chigeza --- North-West University (Potchefstroom Campus), South AfricaThis study explores Black adults’ perceptions of factors that contribute to healthy family functioning. Qualitative interviews were conducted with 18 Black participants between the ages of 26 and 54. They responded to a question on their perceptions of healthy family... -
Characterising the diameter distribution of Sal plantations by comparing normal, lognormal and Weibull distributions at Tilagarh Eco-park, Bangladesh
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Jiban Chandra Deb --- Department of Forestry and Environmental Science, School of Agriculture and Mineral Sciences, Bangladesh Md Habibur Rahman Salman --- Department of Forestry and Environmental Science, School of Agriculture and Mineral Sciences, Bangladesh Md Abdul Halim --- Department of Forestry and Environmental Science, School of Agriculture and Mineral Sciences, Bangladesh Md Qumruzzaman Chowdhury --- Department of Forestry and Environmental Science, School of Agriculture and Mineral Sciences, Bangladesh Anindita Roy --- Department of Forestry and Environmental Science, School of Agriculture and Mineral Sciences, BangladeshFor many years foresters have been using statistical probability density functions to describe and characterise stand structure. Predicting the current and future yields of a stand is essential for successful stand and timber management. Implicit prediction of current yield is... -
Normative indications for Xhosa speaking unskilled workers on the Rey–Osterrieth Complex Figure Test
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Ann Shuttleworth-Edwards --- Department of Psychology, South Africa Heinrich De Kock --- Department of Psychology, South Africa Sarah Radloff --- Department of Statistics, South AfricaThe aim of this study was to establish normative indications for the Rey-Osterrieth Complex Figure (RCF) copy, incidental recall and delayed recall tasks, administered in English on a non-clinical population of Xhosa, unskilled workers (N = 33) (females n = 21; males n = 12), with... -
Values in children's stories in South Africa: an exploratory discourse analysis
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Anne Fleischack --- Department of Psychology, South Africa Trudy Meehan --- Department of Psychology, South AfricaThis study explored the presentation and construction of the values in story texts for children in South Africa. The data were from five children's stories from a widely-circulated weekly newspaper. The story content was analysed for value-laden themes child readers... -
From personal sexuality bias to the life orientation classroom: bridging the gap with cultural intelligence
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Eben Swanepoel --- Department of Psychology of Education, South Africa Christa Beyers --- Department of Psychology of Education, South AfricaThe emotive nature of teaching sexuality and culture is widely acknowledged. However, a working model to promote the teaching of sexuality with sensitivity to both learner needs and community social norms is required. This paper proposes to position cultural intelligence... -
On the distributions of cash flow ratios of listed South African industrial companies
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: W D Hamman --- Graduate School of Business, E V d M Smit --- Graduate School of Business, A C Jordaan --- Graduate School of Business,This paper investigates the assumption of normality in the distribution of cash flow ratios of listed South African industrial companies over the period 1974 to 1993. Twenty eight cash flow ratios are defined and the distributions are investigated for the... -
Comments on “The use of statistical techniques in the interpretation and implementation of South African insider trading legislation”
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: R C van den Honert --- Department of Statistical Science, G D I Barr --- Departments of Statistical Sciences and Economics,In a recent paper Botha (1995) proposes the use of statistical techniques and models from modem finance to show that the abnormal returns on a firm’s share price in some window period immediately before a specific event was not merely... -
Reply: Comments on “The use of statistical techniques in the interpretation and implementation of South African insider trading legislation”
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: D Botha --- Department of Accounting,This is a response to critical comments by Van Der Honert & Barr (1997), reported in this volume, relating to an earlier paper (Botha 1995). Van Der Honert & Barr assert that two blemishes in the reasoning and the model... -
A Comparison of the General Anti-Avoidance Provisions in the Australian and South African Income Tax Acts With Reference to Whether or Not the South African Anti-Avoidance Provisions Would Have Been Applicable to the Facts of FCT v Spotless Services Limited
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: D A Warneke --- Department of Accounting (Tax Section),The decision of the Australian Courts in the case of FCT v Spotless Services Limited was cause for considerable concern among the ranks of the Australian tax fraternity. The decision hinged on an application of the general anti-avoidance provisions (contained... -
The Distribution Properties of the Financial Ratios of Listed South African Industrial Companies: 1980–1989
Item type: Journal Article • Journal: De Ratione • Authors: W R Muil --- University of Stellenbosch, W D Hamman --- University of Stellenbosch, E vd M Smit --- University of Stellenbosch,Financial ratios are widely used tools in financial statement analysis, where often the assumption of normality in the ratio distributions has to be made. The article examines the distributions of nine financial ratios for listed South African industrial companies over... -
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... -
Stock market responses to corporate unbundling in South Africa
Item type: Journal Article • Journal: De Ratione • Authors: Geoffrey Blount --- Department of Business Economics, Sinclair Davidson --- Department of Economics and Finance,This paper examines the effect of the announcement of a restructuring on the returns of the parent companies and the subsidiaries to be unbundled. Abnormal returns are calculated from sixty days prior to the unbundling announcement to sixty days after... -
Encouraging normative smoking behaviour
Item type: Journal Article • Journal: • Authors: Matilde Tchinda Tsayem --- International Service Management, Stenden University of Applied Sciences, Leeuwarden, The Netherlands Elena Cavagnaro --- Academy of International Hospitality Research, Research Group in Service Studies, Stenden University of Applied Sciences, Leeuwarden, The NetherlandsWhy do people smoke in non-smoking areas? What interventions could be used to make a change in observed smoking behaviour? This research builds on Lindenberg and Steg’s goal-framing theory to identify the motivations of norm-breaching behaviour and to suggest intervention... -
Imfobe: self-knowledge and the reach for ethics among former, young, anti-apartheid activists
Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: Pamela Reynolds --- Department of Anthropology, USAThe paper explores the reach for ethics among young people engaged in opposition to the apartheid state in the 1980s. Structured around the Xhosa concept imfobe, variously translated as morality, virtue, goodness, grace, the paper seeks to locate young peoples'... -
The half-yellow man
Item type: Journal Article • Journal: Journal of Endocrinology, Metabolism and Diabetes of South Africa • Authors: BJ Merwitz --- Faculty of Health Sciences, Carbohydrate and Lipid Metabolism Research Unit, South Africa FJ Raal --- Faculty of Health Sciences, Carbohydrate and Lipid Metabolism Research Unit, South Africa -
Cord blood malaria parasitaemia in term, normal birthweight nigerian babies
Item type: Journal Article • Journal: Southern African Journal of Epidemiology and Infection • Authors: Ayebo Sadoh --- Department of Child Health, Nigeria Henry Cummings --- Department of Child Health, Nigeria Wilson Sadoh --- Department of Child Health, Nigeria Adedapo Ande --- Department of Obstetrics and Gynaecology, NigeriaAn important risk factor for congenital malaria is cord blood malaria parasitaemia. We report on the effect of malaria prevention methods [intermittent preventive treatment (IPT) and insecticide-treated nets (ITNs)] on cord blood malaria parasitaemia, as well as the effect of... -
Male on-campus resident students’ social normative behaviour: Influences on lived social climate by same gender beginning-year university students
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Johan Botha --- Education and Human Rights in Diversity Research Unit, South Africa Corlia Twine --- Faculty of Education Sciences, South AfricaThis article reports on research on antecedents of first-year male students’ experiences of senior male students’ aggression in residences at a university in South Africa. Fourteen purposefully selected first-year male student residents (black = 14%; coloured = 7%; white =... -
World Health Organisation staging, adherence to HAART and abnormal cervical smears amongst HIV-infected women attending a government hospital in Johannesburg, South Africa
Item type: Journal Article • Journal: Southern African Journal of Infectious Diseases • Authors: Appolinaire Ciamalenga Katumba --- Faculty of Health Sciences, South Africa Elizabeth Reji --- Department of Family Medicine, Faculty of Health Sciences, South Africa Tabither Gitau --- Population Council (Poverty, Gender and Youth Development), Kenya Cindy Firnhaber --- Right to Care,Introduction: South Africa (SA) has more people living with Human Immunodeficiency Virus (HIV) than any other country in the world. Women infected with HIV have a higher risk of developing cervical dysplasia and cancer than women who are not infected. -
Encouraging normative smoking behaviour
Item type: Journal Article • Journal: Research in Hospitality Management • Authors: Matilde Tchinda Tsayem --- International Service Management, The Netherlands Elena Cavagnaro --- Academy of International Hospitality Research, Research Group in Service Studies, The NetherlandsWhy do people smoke in non-smoking areas? What interventions could be used to make a change in observed smoking behaviour? This research builds on Lindenberg and Steg's goal-framing theory to identify the motivations of norm-breaching behaviour and to suggest intervention... -
The dimensionality of disclosure of HIV status amongst post-partum women in Cape Town, South Africa
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Jo Hunter-Adams --- Health Economics Unit, Public Health and Family Medicine, South Africa Allison Zerbe --- ICAP, USA Tamsin Philips --- Centre for Infectious Diseases Epidemiology & Research, Public Health and Family Medicine, South Africa Zanele Rini --- Centre for Infectious Diseases Epidemiology & Research, Public Health and Family Medicine, South Africa Landon Myer --- Centre for Infectious Diseases Epidemiology & Research, Public Health and Family Medicine, South Africa Greg Petro --- Department of Obstetrics & Gynaecology, South Africa Elaine Abrams --- ICAP, Mailman School of Public Health and College of Physicians and Surgeons, USADisclosure of HIV status to sexual partners and others has been presented as positive health behaviour and is widely encouraged by antiretroviral treatment (ART) programmes, providers and policies. However, disclosure is also highly contextual and its positive effects are not... -
The relationship between Nairobi adolescents’ media use and their sexual beliefs and attitudes
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Ann Neville Miller --- Nicholson School of Communication, USA William Kinnally --- Nicholson School of Communication, USA Hellen Maleche --- Communication Department, Kenya Nancy Achieng’ Booker --- Graduate School of Media and Communications, KenyaAdolescents in sub-Saharan Africa are at risk for contracting HIV. Although media campaigns have educated the population as a whole, few studies are available about the time sub-Saharan African youth spend listening to and viewing sexual messages via the entertainment... -
The influence of lotteries on employees’ workplace HIV testing behaviour
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Martin Weihs --- Social Aspects of HIV/AIDS Research Alliance (SAHARA) and HIV/AIDS, South Africa Anna Meyer-Weitz --- School of Applied Human Sciences, South Africa Friederike Baasner-Weihs --- Nelson Mandela University, South AfricaThe aim of the study was to understand how lottery incentives influenced the HIV counselling and testing (HCT) behaviour and behaviour intention of shop-floor workers who participated in a workplace HCT campaign initiative in two companies in the Nelson Mandela... -
Demographic correlates of normative beliefs about aggression among adolescents from low income communities in South Africa
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Anita Padmanabhanunni --- Department of Psychology, South Africa Martin Gerhardt --- Department of Psychology, South AfricaThe present study investigated the association of age, gender, and family size with normative beliefs about aggression among South African adolescents from low-income areas. Adolescents (n = 229; mean age = 16 years; female = 61%) completed the Normative Beliefs... -
Menstrual abnormalities amongst female South African Hajj pilgrims: a cross-sectional study
Item type: Journal Article • Journal: South African Family Practice • Authors: S Parker --- South African Society of Travel Medicine (SASTM), South Africa S Omar --- Intensive Care Unit, Chris Hani Baragwanath Academic Hospital, University of Witwatersrand, South Africa OH Mahomed --- Discipline of Public Health Medicine, South AfricaIntroduction: Hajj (pilgrimage), the fifth pillar of Islam, is obligatory for every Muslim, male or female, provided that he/she is physically and financially able to do so, at least once in his/her lifetime. One of the rituals of Hajj requires... -
Thromboelastography in mild, chronic liver disease: challenging conventional coagulation tests preceding liver biopsy
Item type: Journal Article • Journal: Southern African Journal of Anaesthesia and Analgesia • Authors: LR Veronese --- Department of Anaesthesia and Perioperative Medicine, South Africa M Miller --- Department of Anaesthesia and Perioperative Medicine, South Africa WC Spearman --- Division of Hepatology, Department of Medicine, South AfricaPatients presenting for liver biopsy may have a deficiency of the synthetic function of the liver. They commonly undergo testing of their INR, which is used to decide if there may be a bleeding risk and if that needs to... -
Maize responses to reduced tillage, different plant residue mulch and nitrogen fertiliser on granitic sandy soils of Zimbabwe
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Walter Mupangwa --- International Maize and Wheat Improvement Centre (CIMMYT), Southern Africa Regional Office, Zimbabwe Isaiah Nyagumbo --- International Maize and Wheat Improvement Centre (CIMMYT), Southern Africa Regional Office, Zimbabwe Eleanor Mutsamba --- International Maize and Wheat Improvement Centre (CIMMYT), Southern Africa Regional Office, Zimbabwe Blessing Mhlanga --- International Maize and Wheat Improvement Centre (CIMMYT), Southern Africa Regional Office, Zimbabwe Jefias Mataruse --- International Maize and Wheat Improvement Centre (CIMMYT), Southern Africa Regional Office, ZimbabweMulching in smallholder conservation agriculture (CA) systems is constrained by lack of adequate crop residues. A three-year study assessed the effects of reduced tillage systems combined with different plant residue mulch and nitrogen (N) fertiliser on nitrogen uptake using the... -
Factors of regular sponsorship of African children: A cross-ethnic study
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Jae-kyeong Kim --- School of Management, South Korea June-hyuk Kwon --- Department of Business Administration, South Korea Nam-hyun Lee --- Department of Performing Arts, South Korea Hyun-ju Choi --- Department of Cultural & Arts Management, South Korea Seung-hye Jung --- School of Dance, South Korea Hyuck-jin Lee --- Department of Business Administration, South Korea Joon-ho Kim --- Department of Business Administration, South KoreaThis study examined psychological well-being influences of personal factors on regular sponsorship of, or donation to, African children living in Africa. Study participants (N = 597) were 338 Koreans (50.3% female, n = 170) and 259 Chinese (56.8% female, n... -
The Tower of London-DX 2nd Edition test: Preliminary norms for educationally disadvantaged Xhosa-speaking individuals
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Rumaine Naidoo --- Department of Psychology, South Africa Ann B. Shuttleworth-Edwards --- Department of Psychology, South Africa Ryan Botha --- Department of Psychology, South Africa Ida Pienaar --- Department of Psychology, South AfricaThis study aimed to construct preliminary normative indications for educationally disadvantaged, Xhosa-speaking South African individuals on the Tower of London-Drexel University 2nd Edition test (TOL-DX 2nd Edition). The TOL-DX 2nd Edition is a commonly employed neurocognitive measure of executive function... -
Weight bias and eating behaviours of persons with overweight and obesity attending a general medical practice in Durban, South Africa
Item type: Journal Article • Journal: South African Family Practice • Authors: RD Govender --- Department of Family Medicine, United Arab Emirates S Al-Shamsi --- Department of Internal Medicine, United Arab Emirates D Regmi --- Department of Family Medicine, United Arab EmiratesBackground: The consequences of obesity for physical health and non-communicable illnesses are well established, but the impact on psychosocial well-being in persons with obesity is much less understood. This study aimed to assess psychosocial constructs such as weight bias affecting... -
Community beliefs, HIV stigma, and depression among adolescents living with HIV in rural Uganda
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Scholastic Ashaba --- Department of Psychiatry, Uganda Christine E Cooper-Vince --- Massachusetts General Hospital, USA Dagmar Vořechovská --- Massachusetts General Hospital, USA Godfrey Zari Rukundo --- Department of Psychiatry, Uganda Samuel Maling --- Department of Psychiatry, Uganda Dickens Akena --- Department of Psychiatry, Makerere College of Health Sciences, Uganda Alexander C Tsai --- Department of Psychiatry, UgandaThe availability of and increased access to antiretroviral therapy (ART) has significantly reduced the morbidity and mortality associated with HIV. As a result, perinatally infected youth are increasingly able to reach adolescence. There is limited information about the psychosocial challenges... -
The influence of institutional isomorphism and organisational factors on environmental management accounting practices of listed Nigerian and South African firms
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: Oluwamayowa O. Iredele --- , South Africa Moloi Tankiso --- , South Africa Michael O. Adelowotan --- , South AfricaThe rising profile of environmental issues, most of which relates to continuous consumption of materials, energy and water by companies, and the continuous accumulation of environmental-related costs, necessitates the need for environmental management accounting (EMA). EMA is regarded as an... -
Effects of social network services (SNS) subjective norms on SNS addiction
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Joon-ho Kim --- The Cultural Policy Network, South Korea Goon-ju Kim --- Department of Future Strategy, South Korea Hyun-ju Choi --- Department of Cultural & Arts Management, South Korea Bong-ihn Seok --- Commercialization Finance Team, South Korea Nam-hyun Lee --- Department of Performing Arts, South KoreaWe examined social network services (SNS) influence on SNS subjective norms for connectivity, perceived pleasure, and addiction. Utilising survey data of ordinary South Africans (N = 927; female = 393), collected by a global research institution (Entrust Survey) between 1... -
Sex differences in normative beliefs about aggression among South African university students
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Emma Wagener --- , South Africa Anita Padmanabhanunni --- , South AfricaThis study investigated gendered normative beliefs about aggression held by South African young adults attending university (N = 255; mean age = 20.24 years, SD = 1.44 years; females = 78%). The students completed a measure of normative beliefs about... -
The effect of cadmium toxicity on Oreochromis niloticus and human health
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: K Abougabal --- , Egypt WA Moselhy --- , Egypt FMM Korni --- , EgyptCadmium levels below permissible limits can be toxic, affecting the health of exposed aquatic organisms and ultimately human health. Although cause and effect links between aquatic organisms and human health have not been elicidated, this study evaluated the effect of... -
The normal tax consequences of home swaps for residents owning property in the Republic of South Africa
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: Magdel Zietsman --- , South Africa Andrea Herron --- , South Africa“Home swapping” has become more accessible due to a global phenomenon, known as the sharing economy. Technological advancement has removed the barriers to international trade and members of home swapping programmes exchange rights to provide each other with accommodation in... -
Electronic waste management in Addis Ababa: The case of Bole and Nefas Silk Lafto sub-cities
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Abenezer Wakuma Kitila --- , Ethiopia Solomon Mulugeta Woldemikael --- , EthiopiaE-waste is a world-wide, interregional, and domestic problem. E-waste management is a challenging task not only due to its speedily increasing volume but more importantly because of its hazardous nature. This study examined the e-waste management and disposal methods in... -
Academic attitude and subjective norms effects on international doctoral students’ academic performance self-perceptions: A moderated-mediation analysis of the influences of knowledge- seeking intentions and supervisor support
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Waqas Khuram --- , China Yanqing Wang --- , China Salim Khan --- , China Aisha Khalid --- , ChinaThis study aimed to examine the relationship between international students’ academic attitude and subjective norms on the one hand, and academic self-perception on the other hand in the context of student’s perception of their knowledge- seeking intention and supervisor support... -
Contractor commitment and the delivery of road infrastructure projects in Uganda: A practitioner perspective
Item type: Journal Article • Journal: Africa Journal of Management • Authors: Andrew Emejeit --- , Uganda Oluka Pross Nagitta --- , Uganda Michael Okoche --- , Uganda Marcia Mkansi --- , South AfricaThis study examined the relationship between commitment (specifically the affective, continuance and normative aspects of commitment) and the delivery of road infrastructure in Uganda. The study employed a cross-sectional survey design with a sample of 266 that was purposively selected... -
Behavioural abnormalities among school-age children living with HIV at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Hayat Ahmed Ali --- , Ethiopia Bezaye Abebe --- , Ethiopia Ayalew Moges --- , Ethiopia Negussie Deyessa --- , EthiopiaBackground: The human immunodeficiency virus infection has manifestations causing behavioural and cognitive abnormalities among children. The aim of this study was to assess the magnitude and correlates of behavioural abnormalities among school-age children living with HIV attending follow-up at the... -
The effect of adjacent vegetation on fire severity in Afrotemperate forest along the southern Cape coast of South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Brandon Giddey --- , South Africa Johan A Baard --- , South Africa Lufuno Vhengani --- , South Africa Tineke Kraaij --- , South AfricaRecently two large wildfires (around the towns of Knysna in 2017 and George in 2018) jointly burnt over 80 000 ha in the southern Cape, South Africa. Here, patches of closed-canopy Afrotemperate forest occur within a matrix of fire-prone (native)... -
Validation of lipid extraction and correction methods for stable isotope analysis of freshwater food webs in southern Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: A van der Merwe --- , South Africa A Myburgh --- , South Africa G Hall --- , South Africa A Kaiser --- , South Africa S Woodborne --- , South AfricaStable isotope analysis is ubiquitous as a method to investigate food-web dynamics at various scales in aquatic ecology. Most studies make use of dorsal muscle tissue, which involves lethal sampling of the fish. The sampling of muscle tissue is often... -
On the parabolicity of linear Weingarten spacelike submanifolds in the de Sitter space
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Railane Antonia --- Universidade Federal da Paraíba, Brazil Henrique F. de Lima --- Universidade Federal de Campina Grande, BrazilIn this paper, we deal with complete linear Weingarten spacelike sub-manifold immersed with parallel normalized mean curvature vector in de Sitter space of index p. Imposing appropriate restrictions on the values of the mean curvature function H, we establish a... -
Notes on normal p-complements and monomial characters
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Xiaoyou Chen --- University of Technology, China Yong Yang --- Texas State University, USALet G be a finite group and Irr(G) be the set of irreducible (complex) characters of G. Let χ ∈ Irr(G) and write cod(χ) = |G : ker χ|/χ(1) as the codegree of χ, where ker χ is the kernel... -
Weak limited sets and operators on Banach lattices
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Farid Afkir --- Moulay Ismaïl University, Morocco Aziz Elbour --- Moulay Ismaïl University, MoroccoIn this paper, we prove that an operator T : E → F , between two Banach lattices, maps order intervals onto weak limited sets if and only if the modulus |ST| exists and is Dunford-Pettis for every Dunford-Pettis operator... -
Normal ordering in the shift algebra and the dual of Spivey’s identity
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Matthias Schork --- , GermanySpivey’s Bell number identity involving Stirling numbers of the second kind was derived by Spivey considering set partitions. Since its original derivation it has been derived (and generalized) by many authors using different techniques. In particular, Katriel gave a proof... -
A lottery incentive system to facilitate dialogue and social support for workplace HIV counselling and testing: A qualitative inquiry
Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Martin Weihs --- , South Africa Anna Meyer-Weitz --- , , South AfricaDespite South African mid-sized companies' efforts to offer HIV counselling and testing (HCT) in the workplace, companies report relatively poor uptake rates. An urgent need for a range of different interventions aimed at increasing participation in workplace HCT has been... -
Rethinking HIV-prevention for school-going young people based on current behaviour patterns
Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Maretha Visser --- , , South AfricaThe aim of the research was to gain increased knowledge regarding the sexual risk behaviour of school-going young people in South Africa after two decades of HIV-education in schools, to contribute to the development of improved HIV prevention strategies. In... -
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... -
Customary ecological conservation of Mwanda-Marungu Pastoral Commons in Taita Hills, south-west Kenya
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Daniel Maghanjo Mwamidi --- Institute of Environmental Sciences and Technology (ICTA), Autonomous University of Barcelona, Spain Abdirizak Arale Nunow --- Moi University, Kenya Pablo Dominguez --- Institute of Environmental Sciences and Technology (ICTA), Autonomous University of Barcelona, SpainRural commons in East-Africa have historically played key socio-economic and environmental sustainability. Despite growing interest in this arena, there are still surprisingly few studies that examine rural customary management of pastoral communities in East Africa. This is striking given that... -
Predicting soil carbon in granitic soils using Fourier-transform mid-infrared (FT-MIR) spectroscopy: the value of database disaggregation
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Kelebohile Rose Seboko --- University of the Free State, South Africa Johan van Tol --- University of the Free State, South Africa Elmarie Kotze --- University of the Free State, South AfricaSoil carbon (C) is an important component in quality assessments and efficient models are required to estimate C rapidly. Accurate C assessments are valuable in monitoring land-use changes. Fourier-transform mid-infrared (FT-MIR) spectroscopy has proved to be a powerful tool for... -
Frame presentations of compact hedgehogs and their properties
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Igor Arrieta --- University of Coimbra, Portugal Javier Gutiérrez García --- University of the Basque Country UPV/EHU, Spain Jorge Picado --- University of Coimbra, PortugalThis paper considers the compact hedgehog as a frame presented by generators and relations, based on the presentation of the frame of extended real numbers. The main focus will be on the point-free version of continuous and semi-continuous functions that... -
Some properties of the Walsh-Nörlund means
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Ushangi Goginava --- United Arab Emirates University, UAE Károly Nagy --- Institute of Mathematics and Computer Sciences, University of Nyíregyháza, Nyíregyháza, HungaryIn the present paper we give a necessary and sufficient condition on monotone weights, which guaranties the Nörlund means of Walsh-Fourier series converge in L 1 norm and CW norm. We also discuss the almost everywhere summability by Nörlund means... -
On norm-attainment in (symmetric) tensor products
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Sheldon Dantas --- Universitat Jaume I, Spain Luis C. García-Lirola --- Universidad de Zaragoza, Spain Mingu Jung --- POSTECH, Republic of Korea Abraham Rueda Zoca --- Universidad de Murcia, SpainIn this paper, we introduce a concept of norm-attainment in the projective symmetric tensor product of a Banach space X, which turns out to be naturally related to the classical norm-attainment of N -homogeneous polynomials on X. Due to this... -
On G-character tables for normal subgroups
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: M.J. Felipe --- Instituto Universitario de Matemática Pura y Aplicada (IUMPA-UPV), Universitat Politècnica de València, Spain M.D. Pérez-Ramos --- Universitat de València, Spain V. Sotomayor --- Instituto Universitario de Matemática Pura y Aplicada (IUMPA-UPV), Universitat Politècnica de València, SpainLet N be a normal subgroup of a finite group G. From a result due to Brauer, it can be derived that the character table of G contains square submatrices which are induced by the G-conjugacy classes of elements in... -
The number fields that are O*-fields II
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Jingjing Ma --- University of Houston-Clear Lake, USA Ashley Martinez --- University of Houston-Clear Lake, USAAn O* -field is a field K for which each partial order with respect to which K is a partially ordered field can be extended to a total order with respect to which K is a totally ordered field. When... -
A note on J -spaces and relatively connected subsets
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Simo S. Mthethwa --- University of KwaZulu-Natal, South Africa Ali Taherifar --- Yasouj University, IranIn this note we present an investigation of J -spaces and other types of spaces related to J -spaces. We characterise these spaces using the notion of relatively connected subsets. For a completely regular J -space X, we give a... -
Numerical radius inequalities for the off-diagonal parts of 2 × 2 operator matrices
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Aicha Ammar --- Mustapha Stambouli University, Algeria Abdelkader Frakis --- Mustapha Stambouli University, Algeria Fuad Kittaneh --- The University of Jordan, JordanWe give some new bounds for the numerical radii of the off-diagonal parts of 2 × 2 operator matrices. A refinement of the triangle inequality for the operator norm is also given. -
The influence of TI-property and subnormality of self-centralizing subgroups of non-prime-power order on the structure of finite groups
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Jiangtao Shi --- Yantai University, P.R. China Na Li --- Beijing Jiaotong University, P.R. ChinaWe obtain a complete classification of the structure of finite groups in which every self-centralizing subgroup of non-prime-power order is a TI-subgroup or a subnormal subgroup. -
Soil nutrient deficiency assessment under soybean cropping systems using the DRIS system in northern and central Benin
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: --- Integrated Soil and Crop Management Research Unit, Benin --- Agricultural Research Centre (CRA) of Agonkanmey, Benin --- Polytechnic School of Abomey-Calavi, Benin --- Agricultural Research Centre (CRA) of Agonkanmey, Benin --- University of Abomey-Calavi, Benin --- Integrated Soil and Crop Management Research Unit, Benin --- Integrated Soil and Crop Management Research Unit, BeninSoybean is one of the promising crops in the Benin agro-industrial sector, but its production is carried out at the expense of the inherent soil fertility. The present study aims to apply the DRIS (Diagnosis and Recommendation Integrated System) for... -
Towards a geometrical equivalence of norms
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Eder Kikianty --- University of Pretoria, South AfricaAngular equivalence of norms, introduced by Kikianty and Sinnamon (2017), is a notion of norm equivalence that is more attuned to the geometry of the norms. For certain geometrical properties and two angularly equivalent norms, it is the case that... -
Stone-Weierstrass approximation revisited
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Anatoly G. Kusraev --- Southern Mathematical Institute of the Vladikavkaz Science Center of the Russian Academy of Sciences, Russia Semën S. Kutateladze --- Sobolev Institute of Mathematics, Siberian Branch of the Russian Academy of Sciences, RussiaThe aim of the present article is to extend the Stone-Weierstrass theorem to functions ranging in a lattice normed space and admitting order rather than topological approximation. We proceed with the machinery of Boolean-valued transfer from lattice normed space to... -
Upper bounds for the numerical radii of powers of Hilbert space operators
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Mohammed Al-Dolat --- Jordan University of Science and Technology, Jordan Fuad Kittaneh --- The University of Jordan, JordanWe present several upper bounds for the numerical radii of 2 × 2 operator matrices. We employ these bounds to improve on some known numerical radius inequalities for powers of Hilbert space operators. In particular, we show that if T... -
On an extension of Hall’s criterion
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Jiangtao Shi --- Yantai University, ChinaLet A and G be finite groups such that A acts coprimely on G by automorphisms, assume that G has a maximal A-invariant subgroup M that is a direct product of some isomorphic simple groups, we prove that if G... -
On A-normaloid d-tuples of operators and related questions
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Najla Altwaijry --- King Saud University, Saudi Arabia Silvestru Sever Dragomir --- Victoria University, Victoria, Australia Kais Feki --- University of Sfax, TunisiLet ß A (ℍ) denote the algebra of bounded linear operators on a complex Hilbert space ℍ that admit A-adjoint operators, where A is a non-zero positive semi-definite operator on ℍ. A commuting operator tuple T = (T 1... -
Notes on sublocales and dissolution
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Jorge Picado --- University of Coimbra, Portugal Aleš Pultr --- Charles University, Czech RepublicThe dissolution (introduced by Isbell in [3], discussed by Johnstone in [5] and later exploited by Plewe in [12, 13]) is here viewed as the relation of the geometry of L with that of the more dispersed T(L) = S(L)op... -
Norm and relative uniform convergence
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Zili Chen --- Southwest Jiaotong University, China Fu Zhang --- Southwest Jiaotong University, ChinaIn this paper, we show that if H is a Dedekind complete normed Riesz space with the local Egoroff property, then H is lattice isomorphic to an ideal of an AM-space if and only if for any order bounded norm... -
The maximum norm error estimate and Richardson extrapolation methods of a second-order box scheme for a hyperbolic-difference equation with shifts
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Dingwen Deng --- Nanchang Hangkong University, China Zhu-an Wang --- Nanchang Hangkong University, China Zilin Zhao --- Nanchang Hangkong University, ChinaThe study aims at the development and theoretical analyses of a box method used to solve a kind of hyperbolic equations with shifts. By using the discrete energy method, it is shown that numerical solutions converge to exact solutions with... -
On p-numerical radius inequalities for commutators of operators
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Abdelkader Frakis --- Mustapha Stambouli University, Algeria Fuad Kittaneh --- The University of Jordan, JordanIn this work, we give some p-numerical radius inequalities for operators as well as for commutators of operators. As applications, when p = ∞, we improve some earlier numerical radius inequalities for operators. Also, we refine the triangle inequalities for... -
A note on the U-Dunford-Pettis operators
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Farid Afkir --- Moulay Ismail University of Meknes, Morocco Aziz Elbour --- Moulay Ismail University of Meknes, MoroccoThe purpose of this note is to give a correct proof of the theorem that concerns the domination property of the class of U-Dunford-Pettis operators obtained by O. Aboutafail, K. El Fahri, J. H’Michane and L. Zraoula [On the class... -
Multiplication operators on the weighted Sobolev disk algebra
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Yucheng Li --- Hebei Normal University, China Kaikai Han --- Hebei University of Economics and Business, China Hexin Zhang --- Hebei Normal University, ChinaLet ⅅ be the unit disk in the complex plane ℂ. For α > −1, the weighted Sobolev disk algebra SA(ⅅ, dAα ) consists of all analytic functions in the weighted Sobolev space W 2,2(ⅅ, dAα ). In this paper,... -
CEO-related announcements, trading activity, and calendar effects
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Katarzyna Byrka-Kita --- University of Szczecin, Poland Mateusz Czerwiński --- University of Szczecin, PolandThis study examines how abnormal trading volumes reflect new information, such as CEO-related announcements. Using hand-collected data on 1,236 CEO reappointments and turnovers from Polish firms listed on the Warsaw Stock Exchange, we show that investor reaction to CEO-related announcements... -
The D-property of extremely normal spaces and the metrizability of certain compact spaces
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Liang-Xue Peng --- Beijing University of Technology, ChinaIn this article, we show that every extremely normal space is a D-space. We introduce a notion called weakly extremely normal with respect to a weak base for a space X. We show that if a space X is weakly... -
Interpolating inequalities for unitarily invariant norms and numerical radii of matrices
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Ahmad Al-Natoor --- Isra University, Jordan Omar Hirzallah --- The Hashemite University, Jordan Fuad Kittaneh --- The University of Jordan, JordanIn this paper, which is a continuation of our works in [9] and [10], we prove several interpolating inequalities for norms and numerical radii of matrices. Special cases of our results present refinements of some known inequalities. Among other results,... -
On the reduction of powers of self-adjoint operators
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Salima Kebli --- University of Oran 1, Algeria Mohammed Hichem Mortad --- University of Oran 1, AlgeriaLet T ∈ B(H) be such that Tn is self-adjoint for some with n ≥ 3. The paper’s primary aim is to establish the conditions that lead to the self-adjointness of T. We pay particular attention to the case where... -
A generalized mid summability in Banach spaces
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Aleena Philip --- , India Deepika Baweja --- , IndiaIn this paper, we study the notion of mid summability in a general framework, emphasizing the key role played by the norm iteration property. We introduce the vector valued sequence space λmid (X ) associated with a Banach space X... -
Bounds on the spread and trace norm of the adjacency matrix of a graph
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Bilal Ahmad Rather --- Shandong University of Technology, China Hilal A. Ganie --- Government Degree College Uri, India M. Imran --- Prince Mohammad Bin Fahd University, Saudi ArabiaThe trace norm of the adjacency matrix A(G) of a graph G is the sum of absolute values of the eigenvalues of A(G) and it is well-known in the literature under the name energy (graph energy) of G. The spread... -
Estimates for the Pre-Schwarzian norm for certain subclasses of analytic functions
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Rashid Ali --- Government College University Faisalabad, Pakistan Mohsan Raza --- Government College University Faisalabad, PakistanFor λ ≥ 1, let be the class of analytic functions f in the open unit disc defined by . Similarly, for the class is defined by . In this article, we present estimates for the pre-Schwarzian norm of functions...
