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Number of isolates of maize root fungi in different crop rotation systems
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: E. Smit --- , South Africa G. D.J van Rensburg --- , South Africa F. H.J. Rijkenberg --- , South AfricaThe effect of monoculture maize and rotation with soybeans, sunflower and groundnuts on the incidence of maize root rot were studied in a long-term rotation trial for three seasons. The number of isolates of the common root colonizing fungi was... -
On the dynamics of demersal fish assemblages off Namibia in the 1990s
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: G. Bianchi H. Hamukuaya O. AlvheimDemersal fish surveys carried out off Namibia from 1990 to 2000 were used to study the dynamics of demersal fish assemblages on the shelf and upper slope. The study was performed on each major assemblage, i.e. over the shelf (100–300... -
Resilience in Families Adapting to Autism Spectrum Disorder
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Leché Kapp --- Nelson Mandela Metropolitan University, Ottilia Brown --- Nelson Mandela Metropolitan University,This study explored adjustment and adaptation in families living with Autism Spectrum Disorder (ASD). Data on family resilience were collected from 19 biological mothers of children with ADS. The data were analysed qualitatively and quantitatively to yield information on factors... -
The spectral theory of commutative C*-algebras: The constructive spectrum
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Bernhard Banaschewski ChristopherJ. MulveyThis paper introduces the notion of a commutative C*-algebra in a Grothendieck topos E and subsequently that of the spectrum MFn A of A, presented as the locale determined by an appropriate propositional theory in the topos E which describes... -
The spectral theory of commutative C*-algebras: The constructive Gelfand-Mazur theorem
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Bernhard Banaschewski ChristopherJ. MulveyIt is shown, for a commutative C*-algebra in any Grothendieck topos E, that the locale MFn A of multiplicative linear functionals on A is isomorphic to the locale Max A of maximal ideals of A, extending the classical result that... -
Representation of slim algebraic regular cozero maps
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: A. Karimi FeizabadiIn this paper a new tool, the cozero maps, is introduced to study algebraic structures in pointfree topology, which generalizes cozero elements and the cozero part of a frame. The slim regular algebraic cozero maps are represented. We proved that... -
Uniqueness and spectral variation in Banach algebras
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: G. Braatvedt --- Department of Mathematics, South Africa R. Brits --- Department of Mathematics, South AfricaLet A be a complex semisimple Banach algebra with identity. We explore the situation whereby a portion of the elements of A have the same spectrum under multiplication by a ∈ A, as under multiplication by b ∈ A; and... -
Effects of fishing on the size and dominance structure of linefish of the Cape region, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: D. Yemane J. G. Field M. H. GriffithsA dataset of linefish catch, effort and fish size distribution records has been assembled from archives to cover three short periods over the 100 years from 1897 to 1998 in four regions of the former Cape Colony, South Africa. Linefish... -
Changes in population structure of the white grouper Epinephelus aeneus as a result of long-term overexploitation in Senegalese waters
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: W Ndiaye --- Institut Fondamental d'Afrique Noire-Cheikh Anta Diop [IFAN-CH. A. Diop], Laboratoire de Biologie et d'Ecologie des Poissons en Afrique de l'Ouest [LABEP-AO], Senegal M Thiaw --- Centre de Recherches Océanographiques de Dakar-Thiaroye [CRODT], Senegal K Diouf --- Institut Fondamental d'Afrique Noire-Cheikh Anta Diop [IFAN-CH. A. Diop], Laboratoire de Biologie et d'Ecologie des Poissons en Afrique de l'Ouest [LABEP-AO], Senegal P Ndiaye --- Institut Fondamental d'Afrique Noire-Cheikh Anta Diop [IFAN-CH. A. Diop], Laboratoire de Biologie et d'Ecologie des Poissons en Afrique de l'Ouest [LABEP-AO], Senegal OT Thiaw --- Graduate Institute of Fisheries and Aquaculture [IUPA], Senegal J Panfili --- Institut de recherche pour le développement [IRD], UMR 5119 Ecologie des systèmes marins côtiers [ECOSYM], SenegalIn Senegal, a significant decrease in catches indicates that many demersal fish stocks are being overexploited. The white grouper Epinephelus aeneus, locally known as the ‘thiof’, is exploited by both small-scale and industrial fisheries. A 28-year database of E. aeneus... -
On the Multiplicative Spectral Characterization of the Jacobson Radical
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: R.M. BritsFor a unital Banach algebra A over C, we give improvements on the well-known multiplicative spectral characterization of the Jacobson radical, (1), in terms of several spectral parameters. In particular, we show that every non-invertible element a ∈ A for... -
The clinical spectrum and cost implications of hospitalised HIV-infected children at Karl Bremer Hospital, Cape Town, South Africa
Item type: Journal Article • Journal: South African Family Practice • Authors: CS Schoeman --- Intercare Walmer, MK Pather --- Division of Family Medicine and Primary Care, Faculty of Health Sciences,Background: HIV infection has become a common risk factor for hospital admission and a major contributor to childhood morbidity in South Africa. There remains a paucity of data describing the cost of hospitalisation of HIV-infected children in South Africa. The... -
First port of call: facing the parents of autism spectrum disorder
Item type: Journal Article • Journal: South African Family Practice • Authors: DL Fewster --- Department of Occupational Therapy, South Africa T Gurayah --- Department of Occupational Therapy, South AfricaBackground: Autism spectrum disorder (ASD) is a debilitating condition for the child as well as the parents and family. Research in ASD is on the increase with many studies coming out of developed countries. To add to the knowledge base... -
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. -
Experiences of father carers of children with Autism Spectrum Disorder: An exploratory study
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Antoinette Pottas --- Department of Psychology, South Africa Athena Pedro --- Department of Psychology, South AfricaThis study aimed to explore the carer experiences of fathers of children with Autism Spectrum Disorder (ASD). A total of eight South African fathers between the ages of 38 and 45 years were the interview informants. They cared for at... -
Neuro-feedback intervention efficacy for treating children with Autism Spectrum Disorder
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Johann Krynauw --- Department of Psychology, South Africa Athena Pedro --- Department of Psychology, South AfricaThis study explored practitioners perceptions of a neuro-feedback intervention in treating children with Autism Spectrum Disorder’s (ASD). Informants were a convenience sample of ten South African neuro-feedback practitioners registered with the Health Professions Council of South Africa (HPCSA). The data... -
Seasonal variation in diet and prey availability in the wall lizard Podarcis vaucheri (Boulenger, 1905) from the Djurdjura Mountains, northern Algeria
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Rabah Mamou --- , France Faïza Marniche --- , , Algeria Mansour Amroun --- , , Algeria Jean-Marie Exbrayat --- , France Anthony Herrel --- , FranceWe studied the composition and seasonal changes in diet and prey selection in the wall lizard Podarcis vaucheri of the Djurdjura Mountains throughout its activity period, from April to October 2014. The analysis of 238 faecal pellets revealed 1 206... -
Parent caregiver perceptions of the behaviour of their children with autism spectrum disorder: A qualitative exploratory study
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Bronwyn R. Britz --- , South Africa Henry D. Mason --- , South AfricaThis study explored parent caregivers’ perspectives of the influence of context on the behaviour of children with autism spectrum disorder (ASD). Applying interpretative phenomenological analysis (IPA), we collected and analysed in-depth interview data from four South African parent caregivers (females... -
Idiosyncratic food preferences of children with autism spectrum disorder in England
Item type: Journal Article • Journal: South African Journal of Clinical Nutrition • Authors: Leanie Huxham --- , South Africa Maritha Marais --- , South Africa Evette van Niekerk --- , South AfricaObjectives: To obtain a better understanding of feeding difficulties experienced by children with autism spectrum disorder (ASD). -
Weed species diversity and shifts in Conservation Agriculture-based crop rotation systems on the Highveld area of South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Elbé Hugo --- , South Africa Maryke Craven --- , South Africa Andries A Nel --- , South AfricaThe occurrence and infestation levels of weed species are known to vary greatly within Conservation Agriculture (CA) systems as weed species will react differently to different habitats. Two on-farm CA trial sites, near Buffelsvallei and Viljoenskroon respectively, were established during... -
Mealtime challenges and food selectivity in children with autism spectrum disorder in South Africa
Item type: Journal Article • Journal: South African Journal of Clinical Nutrition • Authors: Skye Nandi Adams --- , South Africa Raeesa Verachia --- , South Africa Kim Coutts --- , South Africa -
A new type Sturm-Liouville problem with an abstract linear operator contained in the equation
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: K. Aydemir --- Amasya University, Turkey O.Sh. Mukhtarov --- Tokat Gaziosmanpaşa University, TurkeyIn this study we shall introduce to the consideration a new type Sturm-Liouville problem, which differs from the standard problems in that it contain nondifferential term in the equation. Namely, the equation contains an abstract linear operator B, which may... -
Challenges and coping strategies of parents of children with autism spectrum disorder in Eswatini
Item type: Journal Article • Journal: Journal of Child & Adolescent Mental Health • Authors: Fanele Nkonyane --- , Eswatini Thavanesi Gurayah --- , South Africa Thanalutchmy Lingah --- , South AfricaBackground: Research shows that the debilitating effects of autism spectrum disorder (ASD) not only have an impact on the child, but on the parents and caregivers as well. This study aimed to explore the challenges and coping strategies of parents... -
Generalized domination of ergodic elements in ordered Banach algebras
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: S. Mouton --- Stellenbosch University, South Africa A.D. Rabearivony --- Stellenbosch University, South AfricaLet A be an ordered Banach algebra and a, b ∈ A such that 0 ≤ a ≤ b. The domination problem involves finding natural conditions under which properties of b will be inherited by a. In [12] this problem... -
A note on partial-A-isometries and some applications
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Mohamed Amine Aouichaoui --- Institute of Preparatory Studies in Engineering of Monastir Tunisia, University of Monastir, TunisiaIn this paper, the concepts of partial isometry and A-isometry are generalized. The inspiration for our investigation comes from [4, 10, 20, 27, 28, 29]. -
Idempotents in Banach Algebras II
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Rudi Brits --- University of Johannesburg, South Africa Muhammad Hassen --- University of Johannesburg, South Africa Francois Schulz --- University of Johannesburg, South AfricaLet A be a complex and unital Banach algebra, and let E denote the collection of idempotents of A. An old paper of J. Zemánek’s, which was really the starting point of studies of idempotents in general Banach algebras, exhibits... -
Caregiver strain and its predictors among parents of autistic children: a cross-sectional study
Item type: Journal Article • Journal: Journal of Child & Adolescent Mental Health • Authors: Aroosa Nighat --- APPNA Institute of Public Health, Jinnah Sindh Medical University, Pakistan Zaeema Ahmer --- APPNA Institute of Public Health, Jinnah Sindh Medical University, Pakistan Mohammad Ovais --- , Pakistan Fatima Bismah Athar --- Dow University of Health Sciences, Pakistan Lubna Ansari Baig --- APPNA Institute of Public Health, Jinnah Sindh Medical University, PakistanObjective: This study estimates the frequency and predictors of caregiver strain (CGS) among parents of autistic children. -
Spectrum of the Cesàro-Hardy operator in rearrangement invariant spaces
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Meiram Akhymbek --- Institute of Mathematics and Mathematical Modeling, Kazakhstan Kanat Tulenov --- Institute of Mathematics and Mathematical Modeling, Kazakhstan Gulnur Zaur --- Institute of Mathematics and Mathematical Modeling, KazakhstanIn this paper, we investigate the spectrum of the Cesàro-Hardy operator in rearrangement invariant spaces over a finite interval and a half line, thereby extending Boyd’s and Leibowitz’s results for Lp(1 < p ⩽ 8) spaces. In particular, when our... -
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... -
On the preservers of some subsets of the approximate point spectrum
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: H. Benbouziane --- Faculty of Sciences DharMahraz Fes, University Sidi Mohammed Ben Abdellah, Morocco M. Ech-Chérif El Kettani --- Faculty of Sciences DharMahraz Fes, University Sidi Mohammed Ben Abdellah, Morocco I. El Khchin --- Faculty of Sciences DharMahraz Fes, University Sidi Mohammed Ben Abdellah, MoroccoLet be an infinite-dimensional complex Banach space and be the algebra of all bounded linear operators on . For , we consider the following spectral sets in approximate point-spectrum, defined by -
Polar Kangaroos of Type E6
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Yannick Neyt --- Ghent University, Belgium Hendrik Van Maldeghem --- Ghent University, BelgiumA collineation of a point-line geometry is called a kangaroo if its displacement spectrum has a gap; that is, at least one certain distance smaller than the diameter of the geometry cannot occur between a point and its image. In...