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Multi‐species wild herbivore systems vs. domestic single species systems: A comparison of net animal productivity

Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: P.S. Goodman --- Mkuzi Game Reserve,

Short and medium term net annual harvested animal production is compared for six areas situated in the semi‐arid bushveld of north eastern Natal. The landuse on these areas was conservation, commercial game ranching and commercial cattle ranching. The objectives of...

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Growth and desiccation of Themeda triandra and Sporobolus fimbriatus in relation to diminishing moisture availability

Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: J.E. Danckwerts --- Department of Agriculture (Eastern Cape Region),

Water was withheld from individual plants of Themeda triandra and Sporobolus fimbriatus growing in pots in a greenhouse. Leaf extension growth, followed by successive degrees of tiller desiccation, were monitored on a daily basis and related to diminishing moisture availability...

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The Potch System: An approach to the management of semi‐arid grasslands in southern Africa

Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: R.H. Drewes --- Department of Agricultural Development, Republic of South Africa

A host of grassland management systems have been published and recommended. Whereas earlier approaches to grassland management emphasized the systematic resting aspect, the systems published since 1966 have tended to stress the degree of utilization of the grassland sward. In...

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Nitrogen mineralization, nitrification and nitrogen balance in laboratory incubation of soil from natural grassland in the central Orange Free State

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: G.H. Wiltshire --- Department of Soil Science, Republic of South Africa

Air-dried soil from three layers under grassveld was moistened by the addition of 12 levels of water and incubated for up to two years at five temperatures in screw-capped preserving jars with an air-filled head- space equivalent to seven times...

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Loss of nitrogen fertility and its restoration in some Orange Free State soils

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.A. Prinsloo --- Department of Soil Science, Republic of South Africa G.H. Wiltshire --- Department of Soil Science, Republic of South Africa C.C. du Preez --- Department of Soil Science, Republic of South Africa

The effects of present or past cultivation on nitrogen fertility in some central Orange Free State soils were investigated by the comparison of paired samples of cultivated or reverted soils with uncultivated soils situated as closely as possible to one...

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A preliminary investigation of the potential for maize - legume intercropping in the semi-arid area of Sidamo region, Ethiopia. I. Maize response

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Y.B. Alemseged --- , Australia G.W. King --- , Australia L.R. Coppock --- International Livestock Centre for Africa, Ethiopia J.C. Tothill --- International Livestock Centre for Africa, Ethiopia

An intercropping trial involving four legumes, three maize planting densities and two legume planting times was undertaken at Dembela Wacho in the Sidamo region of Ethiopia during the 1987 growing season. The objective was to explore the potential of intercropping...

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A preliminary investigation of the potential for maize - legume intercropping in semi-arid area of Sidamo region, Ethiopia. II. Legume response

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Y.B. Alemseged --- , Australia G.W. King --- , Australia L.R. Coppock --- International Livestock Centre for Africa, Ethiopia J.C. Tothill --- International Livestock Centre for Africa, Ethiopia

An intercropping trial of maize (Zea mays) with two dual-purpose and two forage legumes was undertaken at Dembela Wacho in the Sidamo region of Ethiopia during the 1987 growing season. The objective was to explore the potential of intercropping in...

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Development of a simple empirical model for predicting maize yields in a semi-arid area

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: T.B. Zere --- Department of Soil, Republic of South Africa C.W. van Huyssteen --- Department of Soil, Republic of South Africa M. Hensley --- Department of Soil, Republic of South Africa

A yield prediction model is necessary, together with long-term climate data, to calculate the long-term yields needed for making a quantitative productivity evaluation of a crop ecotope in the form of a cumulative probability function (CPF). In this study the...

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Evaluating the maize production potential of a semi-arid ecotope with four production techniques

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: T.B. Zere --- Department of Soil, South Africa C.W. Huyssteen --- Department of Soil, South Africa M. Hensley --- Department of Soil, South Africa

Water conservation production techniques are needed to boost crop production in semi-arid areas. The in-field rainwater harvesting (IRWH) technique has been developed for this purpose, and found to be successful on clay and duplex soils, but has not yet been...

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Effect of cultivar, seedling age and leaf clipping on establishment, growth and yield of pearl millet (Pennisetum glaucum) and sorghum (Sorghum bicolor) transplants

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: S. Mapfumo --- Department of Crop Science, Zimbabwe C. Chiduza --- Department of Agronomy, Faculty of Science and Agriculture, South Africa E.M. Young --- , UK F.S. Murungu --- Department of Agronomy, Faculty of Science and Agriculture, South Africa P. Nyamudeza --- , Zimbabwe

This study explored the viability of intensifying pearl millet and sorghum production through use of nurseries and transplanting to address the problem of poor stand establishment. The experiments were carried out over two seasons, the 1999/2000 and 2000/2001 seasons in...

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Effect of soil fertility management strategies and resource-endowment on spatial soil fertility gradients, plant nutrient uptake and maize growth at two smallholder areas, north-western Zimbabwe

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. Nyamangara --- Department of Soil Science and Agricultural Engineering, Zimbabwe E. Makarimayi --- Department of Soil Science and Agricultural Engineering, Zimbabwe E.N. Masvaya --- Department of Soil Science and Agricultural Engineering, Zimbabwe S. Zingore --- , Malawi R.J. Delve --- , Zimbabwe

We investigate the effects of smallholder farmer resource—endowment and soil nutrient management strategies on plant nutrient uptake and growth across soil fertility gradients under semi-arid conditions. Soil fertility gradients as influenced by farmers’ resource availability may affect the response of...

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VARIABILITY IN THE INVERTEBRATE FAUNA OF AN INTERMITTENT STREAM OVER THREE CONSECUTIVE MIDSUMMER PERIODS

Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: M. C. Uys --- , South Africa J. H. O'Keeffe --- , South Africa

Non-perennial rivers in semi-arid regions are exposed to unpredictable and highly variable rainfall and hydrology which can have considerable effects on faunal organisation at different scales. Spatial and temporal dynamics in the aquatic invertebrate fauna of an aseasonal intermittent river...

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Estimated spatial requirements of the medium- to large-sized mammals, according to broad habitat units, in the Cape Floristic Region, South Africa

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: AF Boshoff GIH Kerley RM Cowling

Conservation planning in the Cape Floristic Region (CFR) of South Africa, a recognised world plant diversity hotspot, required information on the estimated spatial requirements of selected medium- to large-sized mammals within each of 102 Broad Habitat Units (BHUs) delineated according...

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Effect of Acacia tortilis pods on intake, digestibility and nutritive quality of goat diets in southwestern Eritrea

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: MengistuR Araya RobinsonK Ngugi NashonK R Musimba DicksonM Nyariki

Fresh Acacia tortilis pods were mixed with low quality native grass hay to form the following five rations: 100% hay (T1), 25% pods and 75% hay (T2), 50% pods and 50% hay (T3), 75% pods and 25% hay (T4) and...

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Establishment and early persistence of ten forage legumes under three grazing regimes in southern Mozambique

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: J.P. Muir --- , Mozambique

Leucaena leucocephala, Clitoria ternatea, Macroptilium atropurpureum cv. Siratro, Cassia rotundifolia cv. Wynn, Macrotyloma axillare cv. Archer, Stylosanthes guianensis var. guianensis cv. Graham, S. guianensis var. intermedia cv. Oxley, S. hamata cv. Verano and 5. scabra cv. Fitzroy and cv. Seca...

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Defoliation patterns of three grass species in sourveld grazed by cattle and sheep

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: M.B. Hardy --- , Republic of South Africa N.M. Tainton --- Department of Grassland Science, Republic of South Africa C.D. Morris --- , Republic of South Africa

A point‐based technique was used to determine the effects of grazing, due to stocking rate and cattle‐to‐sheep ratio, on the defoliation pattern of three grass species. At each of 100 systematically located points per grazing treatment the nearest plant of...

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Perspective: Animal‐vegetation relations which optimise production, utilisation and protection of natural resources: An African experience

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: T. Nolan --- , Ireland

The broad objective is to improve the standard of living of farmers/herders through identification of complementary vegetation‐use under mixed animal species grazing. This paper aims to (1) review mixed‐grazing research and development carried out in Ireland and in the semi‐arid...

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Perspective article: Simulation models for semi‐arid rangelands of southern Africa

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: T. Wiegand --- Department of Ecological Modelling, Germany F. Jeltsch --- Department of Ecological Modelling, Germany S. Bauer --- Department of Ecological Modelling, Germany K. Kellner --- Department of Plant‐ and Soil Sciences, South Africa

In semi‐arid regions, the effects of grazing or sparing management on natural communities of long‐lived plants generally take decades to become evident. Event‐driven dynamic behaviour, unpredictable and low rainfall, and complicated interactions between species make it difficult to gather sufficient...

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The influence of Pechuel-Loeschea leubnitziae (wild sage) on grass sward and soil seed bank composition

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: MJ Tedder --- Grassland Science, School of Life Sciences, South Africa KP Kirkman --- Grassland Science, School of Life Sciences, South Africa CD Morris --- Agricultural Research Council, c/o School of Life Sciences, South Africa WSW Trollope --- Research and Development, South Africa MC Bonyongo --- Okavango Research Institute, Botswana

Soil seed banks provide not only a historical record of vegetation composition but also the potential for post-disturbance revegetation. Pechuel-Loeschea leubnitziae (wild sage) is a multistemmed, aromatic shrub, occurring in Namibia, Botswana, Swaziland, Zimbabwe and the northern regions of South...

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How could herd mobility be used to manage resources and livestock grazing in semi-arid rangeland commons?

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Igshaan Samuels --- Agricultural Research Council–Animal Production Institute, c/o Botany and Conservation Biology Department, South Africa Nicky Allsopp --- , South Africa M Timm Hoffman --- Plant Conservation Unit, Department of Biological Sciences, South Africa

Pastoralists in Namaqualand, South Africa, use herd mobility to manage livestock and rangeland resources. However, their socioeconomic conditions and ecological landscapes are changing and we explore the options that are available for pastoralists to respond to these changes. This paper...

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Themeda triandra: a keystone grass species

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Hennie A Snyman --- Animal, Wildlife and Grassland Sciences, South Africa Lachlan J Ingram --- Plant Breeding Institute, Faculty of Agriculture and Environment, Australia Kevin P Kirkman --- Grassland Science, South Africa

Themeda triandra is a perennial tussock grass endemic to Africa, Australia and Asia. Within these regions it is found across a broad range of climates, geological substrates and ecosystems. Because it is widespread across these areas it has great economic...

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Prevalence, Correlates and Perceptions Toward Cigarette Smoking Among Male and Female In-School Adolescents (Aged 11–18 years) in South Africa: Results from the 2008 GYTS Study

Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Karl Peltzer --- Human Sciences Research Council, South Africa

The aim of this study was to estimate the prevalence and identify correlates of current cigarette use among 8470 school-going adolescents (aged 11 to 18 years) in South Africa. A cross-sectional study was carried out in 2008 in South Africa...

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Natural Alternatives For One Dimensional Median Filtering

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: C.H. Rohwer M. Wild

For 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...

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Observations About the Projective Tensor Product of Banach Spaces, II — L^p(0, 1) ⊗X, 1 < p < ∞

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Qingying Bu

In this paper, we first give a sequential representation of Lp (0, 1) ⊗ X, the projective tensor product of Lp (0, 1) and a Banach space X. Then by this sequential representation, we show that L p (0, 1)...

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Higher Derivations and a Theorem By Herstein

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Miguel Ferrero Claus Haetinger

In this paper we extend to the higher derivations a well-known result proved by Herstein concerning derivations in prime rings. We prove results which imply that every Jordan higher derivation of a 2-torsion-free semiprime ring is a higher derivation.

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Maximal Ideals in Near-Rings And Semigroups

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: HenryE. Heatherly RalphP. Tucci

This paper gives conditions that guarantee that a near-ring or a semi- group has maximal right, left, or two-sided ideals. Stronger results are obtained for those semigroups which are adjoint semigroups of rings. Examples are given which illustrate and delimit...

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Multivalued linear projections

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: R.W. Cross D.L. Wilcox

A 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...

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The Dual Space of an Asymmetric Normed Linear Space

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: L.M. García-Raffi Romaguera Sanchez-Pérez

Given 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)...

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On the Unboundedness of Control Operators for Bilinear Systems

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Abdelali Idrissi

The aim of this work is to study the classes of unbounded linear control operators which ensure the existence and uniqueness of the mild and strong solutions of certain bilinear control systems. By an abstract approach, similar to that adopted...

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Completion of Probabilistic Uniform Limit Spaces

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Harald Nusser

In this article completions of special probabilistic semiuniform convergence spaces are considered. It turns out that every probabilitic Cauchy space under a given t-norm T (triangular norm) has a completion which, in the special case of probabilistic Cauchy spaces with...

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Geometric Fuzzification

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: G. Lubczonok C.C. Remsing

We define the concept of fuzzy subobject of a "good" object in an arbitrary concrete category. The approach, called geometric fuzzification, is based upon an appropriate concept of fuzzy point. These fuzzy points are defined on metric spaces which allow...

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Spectral Mapping Theorems For Evolution Semigroups on Spaces of Almost Periodic Functions

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Walter Hutter Frank Räbiger

. We show that the weak spectral mapping theorem holds for evolution semigroups on spaces of periodic functions. Furthermore, we prove the spectral mapping theorem for evolution semigroups on spaces of (weakly asymptotically) almost periodic functions. The results are applied...

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A Lemma On C ₀ -semigroups And Applications

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Hugo Leiva

In this note we characterize a large class of C 0-semigroups which can be applied to prove the existence and the uniqueness of the solutions of many systems of partial differential equations. In fact, we apply our result to a...

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The Lu Lu-semigroup for Envelopes Of Functions

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: E. Malkowsky C.H. Rohwer

In the theory of non-linear smoothers a semigroup of operators has been established, that structures the rank based selectors in a lattice for the purpose of comparison and analysis. The well known upper and lower envelopes of functions can be...

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Irreducibility in Pointfree Topology

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Themba Dube

Irreducible spaces have been studied in topology by several authors. A. H. Stone introduced semi-irreducibility as a way of studying hereditarily compact spaces. In this paper we investigate these concepts in the context of frames.

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Stability of asymptotic properties of Hille-yosida operators under perturbations and retarded differential equations

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Lahcen Maniar

We give conditions on the strongly continuous semigroup (T 0(t)) t≥0, generated by the part of a Hille-Yosida operator A on X 0 := D(A), and a non-autonomous family of operators (B(t)) t≥0 such that the evolution family (U(t,s)) t≥s≥0,...

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A note on localized directional weak lower semi-continuity

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: E. Brüning

In minimization problems for functionals f : M → R, M ⊆ E a subset of some infinite dimensional Banach space E, we typically have to rely on weak (sequential) lower semi-continuity of f on the whole space E even...

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Binary trees equipped with semivaluations

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: H. Pajoohesh M. Schellekens

We consider the set Tn of binary trees with n leaves. This set can be ordered by the so-called "imbalance" order, where two trees are related in the order iff the second is less "balanced" than the first. This order...

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On quasi semi-θ-closed sets in topology

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: M. Caldas D.N. Georgiou S. Jafari

Levine [14] introduced and investigated the notion of generalized closed set. It is the object of this paper is continue the study of the notion of generalized closed set called quasi semi-θ-closed set [3]. This class was obtained by generalizing...

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Katětov revisited: a frame-theoretic excursion

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Themba Dube

The Katětov extension of a frame is, as in the case of spaces, compact only for compact completely regular frames. This result is purely topological because, subject to appropriate foundations, compact regular frames are topologies. In this paper we find...

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Ideals in Heyting Semilattices and Open Homomorphisms

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Jorge Picado Ale&scaron; Pultr Anna Tozzi

Subfitness and its relation to openness and completeness is studied in the context of Heyting semilattices. A formally weaker condition (c-subfitness) is shown to be necessary and sufficient for openness and completeness to coincide. For a large class of spatial...

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L ^p-valued Measures Without Finite X-semivariation for 2 < p < ∞

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Brian Jefferies Susumu Okada Luis Rodrígues-Piazza

We show that for 1 ≤ p < ∞, the property that every L p -valued vector measure has finite X-semivariation in L p (μ, X) is equivalent to the property that every continuous linear map from l...

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TOPOLOGICAL DECOMPOSITIONS OF THE DUALS OF LOCALLY CONVEX VECTOR SEQUENCE SPACES

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: JanH Fourie --- Depart. of Mathematics Potchefstroom, South Africa WilliamH Ruckle --- Depart. of Mathematical Sciences, United States of America

Let Λ be a scalar sequence space which is endowed with a normal locally convex topology. For a separated locally convex space E we denote by Λ(E) the vector space of all sequences g in E for which (>g(i),a<) ε...

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TRACES OF EPIMORPHISM CLASSES

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Lutz Schroder --- Department of Mathematics and Computer Science, University of Bremen, Bremen, Germany,

Classes of morphisms that occur as preimages of the class of all epi-morphisms, of all extremal epimorphisms, respectively of all retractions under some faithful functor are characterized by suitable closure properties. The corresponding question for regular or strict epimorphisms is...

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Automatic Continuity of N-Homomorphisms between Banach Algebras

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: TaherG. Honary --- , Iran H. Shayanpour --- , Iran

An n-homomorphism between algebras is a linear map θ: A→B such that θ(a 1 a 2…an ) = θ(a1)θ(a2)…θ(an ) for all elements a 1,a 2…, an ∈ A. If A is a unital algebra it is known that every...

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Almost Perfectly Continuous Functions

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: D. Singh --- Department of Mathematics, India

The aim of the present paper is to continue the study of almost perfectly continuous (≡ regular set connected) functions initiated by Dontchev, Ganster and Reilly. It turns out that in general the notion of almost perfectly continuity is independent...

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An Algebraic Characterization of Blumberg Spaces

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: M.R. Ahmadi Zand --- Department of Mathematics, Iran

Let X be a topological space and let C(X) be the ring of continuous real-valued functions on X. We study T′(X) as an over-ring of C(X), where T′(X) denotes the set of all real-valued functions on X such that for...

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On the Projective Curvature Tensor of Generalized Sasakian-Space-Forms

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: U.C. De --- Department of Pure Mathematics, India Avijit Sarkar --- Department of Mathematics, India

The object of the present paper is to study the nature of generalized Sasakian-space-forms under some conditions regarding projective curvature tensor. All the results obtained in this paper are in the form of necessary and sufficient conditions.

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On Prime and Semiprime Near-Rings with Generalized Derivation

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Öznur Gölbaşi --- Department of Mathematics, Turkey

Let N be a left near-ring and S be a nonempty subset of N. A mapping F from N to N is called commuting on S if [F(x),x] = 0 for all x € S. The mapping F is called...

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Necessary and sufficient conditions for approximate strong invariance for semilinear differential inclusions

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Alina Ilinca Lazu --- Department of Mathematics, Romania Victor Postolache --- Department of Mathematics, Romania

We establish necessary and sufficient conditions for approximate strong invariance referring to semilinear differential inclusions, conditions expressed in terms of a suitable defined tangency concept.

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Semigroups of transformations with fixed sets

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Preeyanuch Honyam --- Department of Mathematics, Faculty of Science, Thailand Jintana Sanwong --- Department of Mathematics, Faculty of Science, Thailand

Let T (X) denote the semigroup (under composition) of transformations from X into itself. For a fixed subset Y of X, let Fix(X, Y) be the set of all self-maps on X which fix all elements in Y. Then Fix(X,...

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Montel resolvents and uniformly mean ergodic semigroups of linear operators

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: AngelaA. Albanese --- Dipartimento di Matematica e Fisica “E. De Giorgi”, Italy José Bonet --- Instituto Universitario de Matemática Pura y Aplicada IUMPA, Spain WernerJ. Ricker --- Math.-Geogr. Fakultät, Germany

For C 0-semigroups of continuous linear operators acting in a Banach space criteria are available which are equivalent to uniform mean ergodicity of the semigroup, meaning the existence of the limit (in the operator norm) of the Cesàro or Abel...

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HIV/AIDS messages in Malawi and their implications for effective responses

Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Vanessa Houston Alice Hovorka

This paper explores the nature of HIV/AIDS education and information networks in Malawi, with a focus on Dedza district. We consider the role of institutional and personal actors involved in Malawi's recently instated and decentralised behaviour-change intervention strategy, as well...

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HIV/AIDS messages as a spur for conversation among young South Africans?

Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Elizabeth Lubinga --- School of Languages and Communication Studies, South Africa Margrit Schulze --- School of Languages and Communication Studies, South Africa Carel Jansen --- , The Netherlands Alfons Maes --- , The Netherlands

HIV/AIDS messages are often deliberately puzzling so as to increase the chance for them to be used as food for conversation. The South African health organisation ‘loveLife,’ for instance, uses messages that include complicated rhetorical expressions in their media campaigns,...

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Fish assemblages in relation to environmental gradients along a small west African coastal basin, the San Pedro River, Ivory Coast

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: T Koné GG Teugels V N'Douba EP Kouamélan G Gooré Bi

Patterns of fish population composition were examined in the San Pedro River, Ivory Coast, in 2001 to assess whether distinct types of assemblage exist along longitudinal gradients within this small coastal basin. A total of 45 species was found: 28...

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Development and application of a fish-based Sensitivity-weighted Index of Biotic Integrity (SIBI) for use in the assessment of biotic integrity in the Klip River, Gauteng, South Africa

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PJ Kotze GJ Steyn HH du Preez CJ Kleynhans

Biotic indices using fish assemblage characteristics have been applied with great success in river assessments around the world. Internationally the most commonly applied fish index is the Index of Biotic Integrity (IBI), whilst in South Africa the most commonly applied...

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Fish communities along environmental gradients within the Comoé River basin, Côte d'Ivoire

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: StanislasS Yao EssetchiP Kouamélan Tidiani Koné Valentin N'Douba Gooré Bi Frans Ollevier DirkF E Thys van den Audenaerde

Eighty-four sites in the Comoé basin (Côte d'Ivoire, West Africa) were sampled to identify fish assemblages and their relationships with some environmental variables. Seventy-six freshwater fish species were collected from 22 families and 44 genera: 11 marine and/or brackish water...

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Fish assemblages in the Mfolozi–Msunduzi estuarine system, KwaZulu-Natal, South Africa, when not linked to the St Lucia mouth

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L Vivier --- Coastal Research Unit of Zululand, Department of Zoology, South Africa DP Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South Africa RK Owen --- Coastal Research Unit of Zululand, Department of Zoology, South Africa HL Jerling --- Coastal Research Unit of Zululand, Department of Zoology, South Africa

The fish community of the Mfolozi–Msunduzi estuarine system was investigated with particular emphasis on its role as a nursery area for marine fish when the adjacent St Lucia mouth is closed. The mouth was open during March 2007 and 2008...

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Stream degradation, fish abundance and the potential viability of ornamental fisheries in south-western Cameroon

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RE Brummett --- , Cameroon C Cargill --- , Cameroon LM Lekunzé --- , Cameroon D Puddister --- , Cameroon

Fifteen sites on nine second- and third-order streams in the Mount Cameroon area, with varying degrees of human disturbance, were sampled during wet and dry seasons over 21 months in 2003–2005 to estimate their potential for sustainable exploitation of ornamental...

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Fish sampling in the marine-dominated Kariega Estuary, South Africa, using a demersal otter trawl: day/night effects

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SE Bailey --- , South Africa NC James --- , South Africa

Very few demersal fish assemblage studies using otter trawls in estuaries have been done in South Africa and none of these have tested for the effects of diel period. This study aimed to test whether diel period affects otter trawl...

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Productivity Studies of a Large Scale Semi-mechanised Harvesting System for Shortwood in Hilly Terrain

Item type: Journal Article • Journal: South African Forestry Journal • Authors: R.M. de Laborde --- ,

Large scale extraction of shortwood E. grandis timber by means of a semi-mechanised system in hilly terrain gives high productivity from clearfellings. The system employs wheeled tractors and manually loaded low-bed trailers for infield shortwood harvesting. Loads of five to...

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Californian Redwood (Sequoia sempervirens): A Possible Species for Timber Production in South Africa

Item type: Journal Article • Journal: South African Forestry Journal • Authors: B.A. Sesink --- Saasveld Forestry Research Centre,

Californian redwood (Sequoia sempervirens) can be successfully grown in most of the forestry regions of South Africa. On suitable sites it can achieve growth rates in excess of 30 m3 per hectare per year. The relatively fast growth, good form...

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Spatial variability of macrozoobenthic diversity on tidal flats of the Niger Delta, Nigeria: the role of substratum

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: N Zabbey --- Department of Animal Science and Fisheries, Nigeria AI Hart --- Department of Animal and Environmental Biology, Nigeria

Baseline community assemblages and diversity of macrozoobenthic infauna in soft-bottomed intertidal flats at Bodo Creek on the upper reaches of the Andoni–Bonny estuarine system were determined spatially and in relation to sediment particle characteristics for two years from May 2006...

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Comparison of assemblages and some life-history traits of seabirds in the Humboldt and Benguela systems

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RJM Crawford E Goya J-P Roux CB Zavalaga

There are 21 and 15 species of seabirds that breed in the Humboldt and Benguela upwelling systems respectively. Only two species of gull are common to both systems, one as an endemic subspecies to the Benguela system. Eleven species and...

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Alongshore distribution and abundance of fish larvae off the coast of Kenya

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J.M. Mwaluma --- , Kenya B. Kaunda-Arara --- Department of Fisheries and Aquatic Sciences, Kenya J. Rasowo --- Department of Biological Sciences, Kenya

Knowledge is limited on the fish larval assemblage in shallow lagoonal reefs along the Kenyan coast. Fish larvae from five lagoons, spanning 120 km on the Kenyan coast, were sampled in March 2007 and April 2008 to compare interannual spatial...

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Fishing methods for sustainable shrimp fisheries in the Canary Islands (North-West Africa)

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Arrasate-López --- , Spain VM Tuset --- , Spain JI Santana --- , Spain A García-Mederos --- , Spain O Ayza --- , Spain JA González --- , Spain

During the past 20 years, experimental cruises have been conducted around the Canary Islands (North-West Africa) to investigate the biodiversity of the deep-sea ecosystem and to explore new fisheries resources. Although pandalid shrimps were shown to be very abundant in...

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Diet and prey selection in late-stage larvae of five species of fish in a temperate estuarine nursery

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: NA Strydom --- Department of Zoology, South Africa K Sutherland --- Department of Zoology, South Africa TH Wooldridge --- Department of Zoology, South Africa

The plankton assemblage of the permanently open Sundays Estuary in South Africa was sampled seasonally to provide further information on the feeding ecology of the larval stages of fishes in temperate estuaries. Collections were made between winter 2007 and autumn...

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Pelagic fish species assemblages in the southern Benguela

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: GG Louw --- Branch: Fisheries Management, Department of Agriculture, South Africa P Fréon --- CRHMT [Tropical Fish and Mediterranean Research Center], France G Huse --- Institute of Marine Research, Norway MR Lipiński --- Department of Ichthyology and Fisheries Science, South Africa JC Coetzee --- Branch: Fisheries Management, Department of Agriculture, South Africa

Patterns in the co-occurrence of small pelagic fish species within single shoals were investigated using data from 6 814 throws of commercial purse-seiners in South Africa. Assuming that the throw composition reflected the true composition of the assemblage, it was...

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Diffusion of Old Information and Communication Technologies in Disseminating Agricultural Knowledge: An Analysis of Farmers’ Income

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Bibhunandini Das --- ,

This paper analyses the role of old information and communication technologies (ICTs) in knowledge dissemination and the economic outcome of ICT use by farmers. Based on the National Sample Survey data, the paper examines two issues – the role of...

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A preliminary survey and analysis of the spatial distribution of aquatic invertebrates in the Okavango Delta, Botswana

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: HelenF Dallas Belda Mosepele

The spatial distribution of aquatic macroinvertebrates in the Okavango River Delta, Botswana, was investigated during the low-water period in February 2003. This complements an earlier study undertaken during high-water in June 2000. Seventy-five samples were taken in a range of...

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Temporal trends in total phosphorus, temperature, oxygen, chlorophyll a and phytoplankton populations in Hartbeespoort Dam and Roodeplaat Dam, South Africa, between 1980 and 2000

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: CarinE van Ginkel MichaelJ Silberbauer

Eutrophication, phytoplankton blooms and changes to the phytoplankton composition are some of the problems facing the managers of Hartbeespoort Dam and Roodeplaat Dam. Trends, both decreasing and increasing, are visible in the phosphorus concentrations, temperatures, dissolved oxygen concentrations and chlorophyll...

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The effect of fish predation on benthic macroinvertebrates in a seasonal stream in north-western Zimbabwe

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Albert Chakona Brian Marshall Luc Brendonck

The cumulative impact of the entire fish assemblage on benthic macroinvertebrate assemblages was investigated over four months in a removal experiment in isolated pools that persist through the dry season, in an intermittent stream in north-western Zimbabwe. Macroinvertebrate taxonomic richness...

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Fish community response to increased river flow in the Kariega Estuary, a freshwater-deprived, permanently open southern African system

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PD Vorwerk PW Froneman AW Paterson AK Whitfield

The littoral and demersal ichthyofaunal community structure in the freshwater-deprived, permanently open Kariega Estuary was investigated following heavy rain in November 2006 and was compared to low-flow condition data from 1991 and 1996. All surveys took place during the spring...

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Zooplankton composition, abundance and distribution in selected south and west coast estuaries in South Africa

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PH Montoya-Maya --- Department of Ichthyology and Fisheries Science, South Africa NA Strydom --- , South Africa

In order to contribute to the understanding of estuarine zooplankton dynamics in cool-temperate systems, zooplankton samples were collected by plankton tows, using two modified WP2 nets, in nine estuaries on the south and west coasts of South Africa, seasonally between...

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Effects of fishing on a temperate reef community in South Africa 1: ichthyofauna

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Götz --- , South Africa SE Kerwath --- Department of Environmental Affairs, South Africa CG Attwood --- Marine Research Institute, Department of Zoology, South Africa WHH Sauer --- Department of Ichthyology and Fisheries Science, South Africa

Exploitation of temperate reef fish not only affects the target species but potentially changes the composition of reef fish assemblages. This study investigated the effect of fishing on the ichthyofaunal community at protected and exploited sites around the Goukamma Marine...

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Impact of the invader Ipomoea hildebrandtii on grass biomass, nitrogen mineralisation and determinants of its seedling establishment in Kajiado, Kenya

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: JK Mworia JI Kinyamario EA John

The invasive coloniser Ipomoea hildebrandtii aggravates the problem of inadequate grass forage in Kajiado district, Kenya. To test its impact on grass biomass, nitrogen (N) mineralisation and seedling establishment, grazing and coloniser density were controlled using experimental exclosures and weeding...

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When is every Hausdorff continuous interval-valued function bounded by continuous functions?

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Nicolae Dâneţ --- , Romania

In this paper we characterize the topological spaces X for which ℍ ft (X) = ℍ cm (X). Here ℍ ft (X) is the set of all finite Hausdorff continuous interval-valued functions on X and ℍ cm (X) is the...

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A century of woody plant encroachment in the dry Kimberley savanna of South Africa

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: David Ward --- School of Life Sciences, South Africa M Timm Hoffman --- Plant Conservation Unit, Botany Department, South Africa Sarah J Collocott --- School of Life Sciences, South Africa

Woody plant encroachment is frequent in dry savannas. Grazing is often considered to be a major cause of encroachment in dry savannas because grasses are removed by livestock, leaving bare areas for trees to colonise in wetter years. Earlier experiments...

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Anaesthetic management of tracheobronchial disruption during oesophagectomy

Item type: Journal Article • Journal: Southern African Journal of Anaesthesia and Analgesia • Authors: T Bindra --- Department of Anaesthesia and Critical Care, India R Gupta --- Department of Anaesthesia and Critical Care, India P Geetanjali --- Department of Anaesthesia and Critical Care, India

Although tracheobronchial injuries occur rarely during oesophagectomy, the outcome of such injuries is mostly unfavourable. We report the case of a 50-year-old female, American Society of Anesthesiologists (ASA) class 1, who suffered a tracheobronchial injury during transthoracic oesophagectomy. The defect...

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Infertility: an update for the family practitioner

Item type: Journal Article • Journal: South African Family Practice • Authors: TF Kruger --- Department of Obstetrics and Gynaecology, Unit for Reproductive Biology, South Africa JP Van der Merwe --- Department of Obstetrics and Gynaecology, Unit for Reproductive Biology, South Africa

The incidence of infertility is approximately 15–20% (one in every five to six couples). The investigation of the infertile couple begins with a careful history, followed by a physical examination. If any abnormality is observed in the history, the couple...

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A review of metformin and its place in the diabetes guidelines

Item type: Journal Article • Journal: South African Family Practice • Authors: Gail Mkele [AN0001]

Metformin is considered to be the initial drug of choice for type 2 diabetes mellitus, particularly in overweight patients. This is based on its effectiveness in achieving glycaemic control, its favourable effects on weight, its low risk of causing hypoglycaemia...

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Prevalence, Correlates and Perceptions Towards Cigarette Smoking Among Male and Female in School Adolescents (Aged 11–18 Years) in South Africa: Results from the 2008 GYTS Study

Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Karl Peltzer --- HAST, Human Sciences Research Council and Department of Psychology, South Africa

The aim of this study was to estimate the prevalence and identify correlates of current cigarette use among 8,470 school-going adolescents (aged 11 to 18 years) in South Africa. A cross-sectional study was carried out in 2008 in South Africa...

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Lithostructural framework and rare metal (Ta-Nb-Sn-Li-Be) mineralisation in lepidolite from the Ijero-Aramoko pegmatite field, south-western Nigeria

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Oluwatoyin O Akinola --- Department of Geology, Nigeria

A lithological framework and petrochemical features relating to Ta-Nb-Sn-Li-Be mineralisation in lepidolite from the Ijero-Aramoko pegmatite field, south-western Nigeria were investigated. Systematic geological mapping revealed that the pegmatite occurs as steeply inclined intrusive bodies in a basement of gneisses and...

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A morphological description of the sagittal otoliths of two mormyrids, Marcusenius macrolepidotus and Petrocephalus catostoma (Family: Mormyridae)

Item type: Journal Article • Journal: African Zoology • Authors: N.N. Nicolaai --- Department of Zoology and Biology, South Africa A. Jooste --- Department of Zoology and Biology, South Africa

The morphology of the sagittal otoliths of two South African mormyrid fish, Marcusenius macrolepidotus and Petrocephalus catostoma, were studied to determine possible morphological significance. The sagittae of M. macrolepidotus and P. catostoma are kidney-shaped and oblong, respectively. The ventral margin...

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Spring body condition, moult status, diet and behaviour of white-faced whistling ducks (Dendrocygna viduata) in northern South Africa

Item type: Journal Article • Journal: African Zoology • Authors: Scott A. Petrie --- Centre for Water in the Environment, University of the Witwatersrand, South Africa

Many white-faced whistling ducks (Dendrocygna viduata) have responded to European colonization by overwintering on irrigation and stock-watering ponds in the semi-arid interior of South Africa. I studied the body condition, diet, behaviour and moult intensity of whitefaced whistling ducks prior...

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An ultrastructural investigation of Argulus personatus Cunnington, 1913 (Crustacea: Branchiura) from Lake Tanganyika, northern Zambia

Item type: Journal Article • Journal: African Zoology • Authors: Quinton Tam --- Department of Zoology, South Africa Annemarié Avenant-Oldewage --- Department of Zoology, South Africa Ernest H. Williams --- Department of Marine Sciences,

Sixteen male and one female specimen of Argulus personatus Cunnington, 1913, were collected from Bathybates ferox Boulenger, 1898, from Lake Tanganyika in northern Zambia. Light and scanning electron microscopy (SEM) examinations documented a thickening of cuticle located on the dorsal...

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Advertisement call and tadpole morphology of the clutch-guarding frog Mantidactylus argenteus from eastern Madagascar

Item type: Journal Article • Journal: African Zoology • Authors: Silvia Vejarano --- Institute for Biodiversity and Ecosystem Dynamics, Zoological Museum, University of Amsterdam, the Netherlands Meike Thomas --- Department of Genetics, Evolutionary Genetics, Germany Frank Glaw --- Zoologische Staatssammlung, Germany Miguel Vences --- Institute for Biodiversity and Ecosystem Dynamics, Zoological Museum, University of Amsterdam, the Netherlands

We provide the first descriptions of the tadpole and advertisement call of Mantidactylus argenteus. Calls consist of 6–15 short and rather melodious notes, with a dominant frequency at 4100–4400 Hz and are emitted from arboreal positions during the day. The...

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Waterfowl abundance and diversity in relation to season, wetland characteristics and land-use in semi-arid South Africa

Item type: Journal Article • Journal: African Zoology • Authors: Ashley A. Raeside --- Department of Biology, Canada Scott A. Petrie --- Long Point Waterfowl and Wetlands Research Fund, Bird Studies Canada, Canada Thomas D. Nudds --- Department of Integrative Biology, Ecology Group, Canada

We studied waterfowl abundance and diversity in relation to season (wet vs dry), wetland characteristics (vegetation and morphometrics) and land-use in a semi-arid agricultural region of South Africa to determine how waterfowl respond to various wetland characteristics, particularly those of...

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A new species of Asemonea from Zambia (Araneae: Salticidae: Lyssomaninae)

Item type: Journal Article • Journal: African Zoology • Authors: Wanda Wesołows --- Institute of Zoology, Wroclaw University, Poland

A new spider species from Zambia belonging to the poorly-known genus Asemonea, is described. It appears to be related to Asemonea maculata from the Ivory Coast.

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Rapid assessment of montane anuran communities in the Albertine Rift: Hyperolius castaneus Ahl, 1931 as an umbrella species for conservation

Item type: Journal Article • Journal: African Zoology • Authors: Ulrich Sinsch --- Institute of Integrated Sciences, Department of Biology, Germany Eli Greenbaum --- Department of Biological Sciences, U.S.A. Chifundera Kusamba --- Laboratoire d’Herpétologie, Département de Biologie, Democratic Republic of Congo Edgar Lehr --- Institute of Integrated Sciences, Department of Biology, Germany

The species richness of seven montane anuran communities of the Albertine Rift was assessed with visual and acoustic transects. A total of 28 anuran species were detected. The highland anuran communities at (2000–2800 m) were dominated by up to nine...

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Acoustic niche partitioning in an anuran community inhabiting an Afromontane wetland (Butare, Rwanda)

Item type: Journal Article • Journal: African Zoology • Authors: Ulrich Sinsch --- Institute of Integrated Sciences, Department of Biology, Germany Katrin Lümkemann --- Institute of Integrated Sciences, Department of Biology, Germany Katharina Rosar --- Institute of Integrated Sciences, Department of Biology, Germany Christiane Schwarz --- Institute of Integrated Sciences, Department of Biology, Germany Maximilian Dehling --- Institute of Integrated Sciences, Department of Biology, Germany

The species richness and calling activity of an anuran community inhabiting an agricultural wetland area at 1645 m a.s.l. near Butare, Rwanda, was assessed using visual and acoustic transects. The community included 15 species which were readily distinguishable using morphological,...

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Characteristics of the alarm calls of buff-streaked chat groups and African stonechat pairs in response to increased distances from surrogate raptors and snakes

Item type: Journal Article • Journal: African Zoology • Authors: N. Seoraj-Pillai --- Department of Nature Conservation, South Africa G. Malan --- Department of Nature Conservation, South Africa

Many animals emit alarm calls in response to a potential predator. These calls may transmit information about predator type and response urgency. This study compared the alarm calls of the social buff-streaked chat, Oenanthe bifasciata, to the asocial African stonechat,...

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Confinement lowers fertility rate of helmeted guinea fowl (Numida meleagris) eggs

Item type: Journal Article • Journal: African Zoology • Authors: Dennis M. Kimata --- School of Biological Sciences, University of Nairobi, Kenya Richard W. Mwangi --- School of Biological Sciences, University of Nairobi, Kenya Peter M. Mathiu --- Department of Veterinary Anatomy and Physiology, Kenya

Guinea fowl is a common game bird in Africa and there have been efforts to domesticate it for use as a source of human food. An important obstacle in successful domestication of guinea fowl is their low fertility rate.We studied...

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To what extent are students as middle managers at a training hotel involved in strategic decision making?

Item type: Journal Article • Journal: • Authors: Tjeerd Zandberg --- Stenden University, the Netherlands

Research has shown that middle managers can exert major upward or downward influence on their organisation’s strategy. In the practice department of our hotel school, senior students act as managers to train managerial competences. To analyse if this reflects reality,...

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Dissemination effort, innovation attributes, and variations in innovation dissemination rate

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Mawuena Aggey --- Process Technology and Innovation Research, Ghana Nana Kwamina Tekyi Ghartey --- Centre for Development Studies, Ghana Charles Kweku Brown --- Centre for Development Studies, Ghana

Innovation-decision type, communication channels, social system, and change agents’ promotion effort influence innovation adoption, but 49–87% of variance in adoption rates is explained by perceived innovation attributes (Rogers 1995). Relationships between adoption rates and these variables are much researched but...

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Macroinvertebrate variation in endorheic depression wetlands in North West and Mpumalanga provinces, South Africa

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L Foster --- Department of Zoology, South Africa W Malherbe --- Water Research Group, Unit for Environmental Science and Management, South Africa M Ferreira --- Department of Zoology, South Africa JHJ van Vuren --- Department of Zoology, South Africa

Aquatic macroinvertebrates are rarely used in wetland assessments due to their variation. However, in terms of biodiversity, these invertebrates form an important component of wetland fauna. Spatial and temporal variation of macroinvertebrate assemblages in endorheic depressions (locally referred to as...

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Reconsidering displacement in southern Africa

Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: Chris de Wet --- Department of Anthropology, South Africa

In the light of developments in the southern African region over the last number of years, the paper argues for a reconsideration, and an extension, of the way in which the concept of ‘displacement’ has conventionally been understood. It considers...

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Greeting rituals as everyday management of differences among RasTafari groups in Stellenbosch

Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: Lennox Olivier --- Sociology and Social Anthropology, Stellenbosch University,

Greeting is a meaningful part of everyday interaction among individuals from different RasTafari groups in Stellenbosch, since it contributes to the construction and maintenance of the identity and boundaries of groups. Drawing upon extensive participant observation, I first look at...

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Fish associated with artificial reefs in False Bay, South Africa: a preliminary survey

Item type: Journal Article • Journal: African Zoology • Authors: Y.A.R.G Lechanteur --- Marine Biology Research Institute, South Africa C.L. Griffiths --- Marine Biology Research Institute, South Africa

This study compares the suprabenthic fish assemblages inhabiting eight shipwrecks in False Bay with those found on adjacent natural reefs. 3411 fishes of 18 species were recorded on the wrecks. Species densities recorded on wrecks in both shallow and deep...

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Estimation of the lion (Panthera leo) population in the southwestern Kgalagadi Transfrontier Park using a capture–recapture survey

Item type: Journal Article • Journal: African Zoology • Authors: J.G. Castley --- Conservation Services, South African National Parks, South Africa M.H. Knight --- Conservation Services, South African National Parks, South Africa M.G.L. Mills --- Conservation Services, South African National Parks, Endangered Wildlife Trust, and Mammal Research Institute, University of Pretoria, South Africa C. Thouless --- Department of Wildlife and National Parks, Botswana

A previous estimate of the lion (Panthera leo) population in the southwestern Kgalagadi Transfrontier Park (KTP) was made over 20 years ago. This together with increased fears regarding the viability of the population as a result of recent killings of...

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Cryptic species of sharp-nosed reed frogs in the Hyperolius nasutus complex: advertisement call differences

Item type: Journal Article • Journal: African Zoology • Authors: Alan Channing --- Zoology Department, South Africa David Moyer --- , Marius Burger --- Zoology Department, South Africa

The sharp-nosed reed frog is widespread in Africa. Although currently recognized as one species, suggestions have been made that more than one species might exist. We analysed 237 calls of 69 males from 19 localities in the western to southern...

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Additional morphological information on two species of Caligus (Copepoda: Caligidae) parasitic on South African marine and estuarine fish

Item type: Journal Article • Journal: African Zoology • Authors: N.J. Grobler --- Department of Zoology and Entomology, South Africa J.G. Van As --- Department of Zoology and Entomology, South Africa P.A.S. Olivier --- School of Molecular and Life Sciences, South Africa

Two species of Caligus that are parasitic on fish were collected from Lake St Lucia, South Africa.

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First records of the echiurans Anelassorhynchus semoni (Fischer, 1896) and A. mucosus (Ikeda, 1904) from the east coast of southern Africa (Echiuroinea: Echiuridae)

Item type: Journal Article • Journal: African Zoology • Authors: Ramlall Biseswar --- School of Biological and Conservation Sciences, U.S.A

Two species of echiurans (Echiura), Anelassorhynchus semoni (Fischer, 1896) and A. mucosus (Ikeda, 1904), were collected from the intertidal rocky shores at Perriers Rock on the Kwazulu-Natal north coast. This is the first known record of these species from South...

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Carbon stocks in a 50‑year‑old Eucalyptus camaldulensis stand in Sicily, Italy

Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Riccardo Scalenghe --- Dipartimento Scienze Agrarie e Forestali, Italy Luisella Celi --- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Italy Giovanna Costa --- Dipartimento Scienze Agrarie e Forestali, Italy V Armando Laudicina --- Dipartimento Scienze Agrarie e Forestali, Italy Stefania Santoni --- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Italy Dario Vespertino --- Dipartimento Scienze Agrarie e Forestali, Italy Tommaso La Mantia --- Dipartimento Scienze Agrarie e Forestali, Italy

Eucalyptus stands in semi‑arid areas may contribute to enhance carbon (C) stocks in both biomass and soil. However, the limited information available is mainly focused on short‑rotation plantations. In this study, the above‑ and below‑ground C pools in five 50‑year‑old...

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Influence of growth media and regulators on vegetative propagation of rosemary (Rosmarinus officinalis L.)

Item type: Journal Article • Journal: East African Agricultural and Forestry Journal • Authors: P. Kiuru --- Kenya Agricultural Research Institute (KARI) Thika, Kenya S. J. N. Muriuki --- Kenya Agricultural Research Institute (KARI) Thika, Kenya S. B. Wepukhulu --- Kenya Agricultural Research Institute (KARI) Thika, Kenya S. J. M. Muriuki --- Kenya Agricultural Research Institute (KARI) Thika, Kenya

Rosemary (Rosmarinus officinalis) is a woody, perennial herb with fragrant evergreen needle-like leaves and a lovely fragrance. Leaves are finely chopped and used to flavour dishes. Rosemary propagation is done through either seed or stem cutting. Seeds of rosemary are...

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Use of low cost pest exclusion nets can boost cabbage yield

Item type: Journal Article • Journal: East African Agricultural and Forestry Journal • Authors: J. Kiptoo --- Department of Biological Science, Kenya M. Kasina --- National Sericulture Research Center (KALRO), Kenya F. Wanjala --- Department of Biological Science, Kenya P. Kipyab --- Kenya Plant Health Inspectorate Service, Kenya L.A. Wasilwa --- Kenya Agricultural Research Institute, Kenya M. Ngouajio --- Michigan State University, USA T. Martin --- Cirad UR Hortsys, France

In this study, low-cost pest exclusion nets (lcPENs) were evaluated to determine their efficacy in reducing pest infestation and enhancing yields of cabbage at KALRO Kabete and PTC (Practical Training Centre) Thika, Kenya, from March to September 2011 both at...

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Effect of Prosopis (mesquite) invasion and clearing on vegetation cover in semi-arid Nama Karoo rangeland, South Africa

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Thabisisani Ndhlovu --- Department of Conservation Ecology and Entomology, South Africa Suzanne J Milton --- Percy FitzPatrick Institute of African Ornithology, DST–NRF Centre of Excellence, South Africa Karen J Esler --- Centre for Invasion Biology and Department of Conservation Ecology and Entomology, South Africa

The Nama-Karoo is the largest of the three biomes that comprise the semi-arid Karoo-Namib ecoregion of southern Africa. Large tracts of Nama-Karoo rangeland have been invaded by alien leguminous trees of the genus Prosopis. We assessed the impact of Prosopis...

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Field evaluation of deficit irrigation effects on tomato growth performance, water-use efficiency and control of parasitic nematode infection

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Osama Mohawesh --- Department of Plant Production, Jordan

Two field experiments were conducted using a common tomato cultivar (GS12) to assess the effect of deficit irrigation (DI) regimes on tomato growth performance, and on root-knot nematode Meloidogyne javanica galling and abundance. Irrigation treatments consisted of five irrigation regimes:...

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Liver dysfunction as the presenting feature of disseminated cryptococcosis

Item type: Journal Article • Journal: Southern African Journal of Infectious Diseases • Authors: Shailaja Shukla --- Department of Pathology, India Jyoti Garg --- Department of Pathology, India Gunjan Mahajan --- Department of Pathology, India Sunita Sharma --- Department of Pathology, India

Disseminated cryptococcosis is rare in immunocompetent individuals with central nervous and respiratory systems being the most common initial sites of involvement. Liver dysfunction as a presenting feature of disseminated cryptococcosis has been reported rarely, with the majority of patients being...

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On character amenability of semigroup algebras

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: S.M. Maepa --- , , South Africa O.T. Mewomo --- , , South Africa

We study the character amenability of semigroup algebras. We work on general semigroups and certain semigroups such as inverse semigroups with a finite number of idempotents, inverse semigroups with uniformly locally finite idempotent set, Brandt and Rees semigroup and study...

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Integral and discrete representations of some H _q-semiclassical forms

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Manoubi Mejri --- , , Tunisia

The aim of this paper is to deduce integral and discrete representations of some H q -semiclassical forms of class one. These forms were studied by B. Bouras and F. Marcellan in [1], (Quadratic decomposition of a family of...

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Osmolality of modified enteral tube feeds for adults in hospitals across the Western Cape Province

Item type: Journal Article • Journal: South African Journal of Clinical Nutrition • Authors: L. Schafer --- Division of Human Nutrition, South Africa K. Templin --- Division of Human Nutrition, South Africa P. Dlamini --- Division of Human Nutrition, South Africa Jm. Kruger --- Department of Interdisciplinary Health Sciences, South Africa E. Van Wyk --- Division of Human Nutrition, South Africa

Objectives: The first aim of this study was to determine the incidence of use, reasons for use, and procedures/recipes followed in modifying enteral tube feeds (ETFs) for adults in state and private hospitals across the Western Cape Province (WCP), South...

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Further evidence that in African acacia, white is a warning colour to herbivores: the white pseudo-galls of Vachellia seyal

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Jeremy Midgley --- University of Cape Town, South Africa Huyam Altayeb --- University of Cape Town, South Africa Patrick Mbosso --- University of Yalounde 1, Cameroon

Pseudo-galls of three East African acacia (Vachellia) species were compared to determine the correlates of gall colour and their potential defensive functions. Although all three species produce white thorns, the pseudo-galls of V. gerrardii and V. drepanolobium are dark coloured...

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Impact of Prosopis (mesquite) invasion and clearing on vegetation species composition and diversity in semi-arid Nama-Karoo rangeland, South Africa

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Thabisisani Ndhlovu --- Department of Conservation Ecology and Entomology, South Africa Suzanne J Milton --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South Africa Karen J Esler --- Centre for Invasion Biology and Department of Conservation Ecology and Entomology, South Africa

The Nama-Karoo biome occupies 28% of South Africa’s land area. Alien leguminous trees of the genus Prosopis have invaded large tracts of Nama-Karoo rangeland. We evaluated the impact of Prosopis invasion and clearing on vegetation species composition and diversity (alien...

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Making Sense of Changing Hats: A Study of the Nigeria, Vietnam, and Azerbaijan/Kazakhstan Projects within the Norwegian Statoil and British BP Strategic Alliance

Item type: Journal Article • Journal: Africa Journal of Management • Authors: Lin Lerpold --- Stockholm School of Economics, Sweden Lena Zander --- Department of Business Studies, Sweden

To explore group-based identities and collective sensemaking in the context of a cross-border alliance, a qualitative exploratory study was initiated. The emphasis was on interpretation of issues, within and around an interfirm partnership and the alliance process, perceived by those...

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Clonal propagation of Pterocarpus santalinoides L'Hér. ex DC.: the effect of substrate, cutting type, genotype and auxin

Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Catherine Ky-Dembele --- World Agroforestry Centre – West Africa and Central Regional Office - Sahel Node – BP, Mali Jules Bayala --- World Agroforestry Centre – West Africa and Central Regional Office - Sahel Node – BP, Mali Antoine Kalinganire --- World Agroforestry Centre – West Africa and Central Regional Office - Sahel Node – BP, Mali Fatoumata Tata Traoré --- World Agroforestry Centre – West Africa and Central Regional Office - Sahel Node – BP, Mali Bréhima Koné --- World Agroforestry Centre – West Africa and Central Regional Office - Sahel Node – BP, Mali Alain Olivier --- Université Laval, Canada

Pterocarpus santalinoides is a multipurpose tree species, native to Africa and South America. However, excessive pruning for fodder is jeopardising its seed production leading to poor regeneration in the Sahel region. Efficient vegetative propagation techniques may overcome this concern. To...

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Disseminated fungal infection in an HIV-infected patient due to Aureobasidium pullulans

Item type: Journal Article • Journal: Southern African Journal of Infectious Diseases • Authors: Wesley G. van Hougenhouck-Tulleken --- Division of Rheumatology, Department of Internal Medicine, South Africa Garrison Mathole --- Department of Internal Medicine, South Africa Alan Karstaedt --- Division of Infectious Diseases, Department of Internal Medicine, South Africa Nimmisha Govind --- Division of Rheumatology, Department of Internal Medicine, South Africa Magendhree Moodley --- Department of Clinical Microbiology and Infectious Diseases, National Health Laboratory Service, South Africa Sharona Seetharam --- Department of Clinical Microbiology and Infectious Diseases, National Health Laboratory Service, South Africa Nelesh P. Govender --- National Institute for Communicable Diseases(Centre for Opportunistic, Tropical and Hospital Infections), a division of the National Health Laboratory Service, South Africa Colin N. Menezes --- Division of Infectious Diseases, Department of Internal Medicine, South Africa

In South Africa, novel fungal pathogens have emerged as an important cause of disease in HIV-infected individuals. The clinical presentation is characteristically prolonged, insidious and the diagnosis elusive, often being made post mortem. We report an HIV-infected individual with a...

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Enigmatic tissue in the orobranchial chamber of cardinalfishes of the genus Siphamia (Perciformes, Apogonidae)

Item type: Journal Article • Journal: African Zoology • Authors: Ofer Gon --- South African Institute for Aquatic Biodiversity, South Africa Shirley C Pinchuck --- Electron Microscopy Unit, South Africa

An unusual tissue covering the tongue and occasionally part of the gill chamber of many species of the Indo-Pacific cardinalfish genus Siphamia is described and compared with an earlier description of a similar tissue found in the cichlid species Alcolapia...

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To what extent are students as middle managers at a training hotel involved in strategic decision making?

Item type: Journal Article • Journal: Research in Hospitality Management • Authors: Tjeerd Zandberg --- Stenden University, the Netherlands

Research has shown that middle managers can exert major upward or downward influence on their organisation's strategy. In the practice department of our hotel school, senior students act as managers to train managerial competences. To analyse if this reflects reality,...

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Development of a charcoal-fuelled dryer for the production of organic fertilizer from hog waste

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: B.O. Akinnuli --- Department of Mechanical Engineering, Nigeria O.P. Bodunde --- Department of Mechanical Engineering, Nigeria

The negligence of livestock farmers regarding waste disposal and inadequate waste control facilities are becoming a serious health and environmental hazard. In this study, a charcoal-fuelled dryer was developed to eliminate the moisture content in hog waste for easy conversion...

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Organic carbon associated with tillage-induced aggregates of some quartz-dominated loamy soils in a semi-arid region of South Africa

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Isaiah IC Wakindiki --- School of Agriculture, South Africa Sarah K Njeru --- Department of Agronomy, South Africa

Tillage breaks down soil aggregates exposing the associated organic matter to increased degradation. The extent of degradation depends on the soil properties, mainly texture and mineralogy. The objective of this study was to determine the amount of soil organic carbon...

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Three new species of Arthroleptella Hewitt, 1926 (Anura: Pyxicephalidae) from the Cape Fold Mountains, South Africa

Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Andrew Turner --- , South Africa Alan Channing --- , South Africa

A comprehensive survey of the Cape Fold Mountains, South Africa, was undertaken for moss frogs of the genus Arthroleptella. Advertisement calls were recorded and voucher specimens collected for all populations encountered. A molecular phylogeny was constructed for the entire genus...

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Principals’ experiences of being disempowered by union members

Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Chris Myburgh --- Department of Educational Psychology, South Africa Marie Poggenpoel --- Department of Educational Psychology, South Africa Veronica Mapitso Kgabo --- Department of Educational Psychology, South Africa

This study explored school principals’ experience of managing unionised schools in South Africa. Qualitative in-depth phenomenological interviews were conducted with a purposeful selected sample of 13 school principals of unionised schools (age range 36-60 years). The school principals responded to...

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Eelgrass beds and bare substrata – sparid and mugilid composition in contrasting littoral estuarine habitats

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Pollard --- Department of Zoology and Entomology, South Africa AN Hodgson --- Department of Zoology and Entomology, South Africa HM Kok --- Port Elizabeth Museum, South Africa AK Whitfield --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa

Seagrass beds serve as nursery grounds for many fish species and often play an important role in the juvenile stages of economically and recreationally important fishes. The eelgrass Zostera capensis is the dominant submerged macrophyte in permanently open South African...

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Contrasting invasion patterns in intertidal and subtidal mussel communities

Item type: Journal Article • Journal: African Zoology • Authors: Lisa Skein --- Department of Botany and Zoology, South Africa Mhairi Alexander --- School of Science and Sport, UK Tamara Robinson --- Department of Botany and Zoology, South Africa

Two invasive mussel species are known from South Africa, Mytilus galloprovincialis and Semimytilus algosus. Most of the existing research on these invaders has focused on the intertidal zone, with little attention paid to subtidal habitats. This study addresses this knowledge...

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Towards plant-centred methodologies in anthropology

Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: Diana Gibson --- Department of Anthropology and Sociology, South Africa

This paper reflects on research on medicinal plants in the Matzikama Local Municipality, Western Cape, in order to elaborate on methodological possibilities and their problematic in such studies. Classical ethnographic research is usually conducted from an anthropocentric viewpoint, but our...

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Impacts of alien ‘ecosystem engineers’ overwhelm interannual and seasonal shifts in rocky-shore community composition on Marcus Island, South Africa

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Sadchatheeswaran --- Department of Biological Sciences and Marine Research Institute, South Africa GM Branch --- Department of Biological Sciences and Marine Research Institute, South Africa CL Moloney --- Department of Biological Sciences and Marine Research Institute, South Africa TB Robinson --- Department of Botany and Zoology, South Africa

The South African coastline has been invaded by numerous alien species. Rare pre-invasion (1980) and post-invasion datasets (2001 and 2012) exist for Marcus Island, a small land-tied island in Saldanha Bay, South Africa. These snapshot datasets of the island’s intertidal...

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A Decision Tree and Naïve Bayes algorithm for income tax prediction

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: G. V. Mabe-Madisa --- Department of Decision Sciences, South Africa

One of the concerns regarding the tax collection system is incorrect case selection. Manual selection of audit cases by auditors (whose role is to detect individual cases of tax non-compliance) based on their expert knowledge of the taxpayers’ behaviour, cannot...

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Adherence of patients with type 2 diabetes mellitus with the SEMDSA lifestyle guidelines

Item type: Journal Article • Journal: Journal of Endocrinology, Metabolism and Diabetes of South Africa • Authors: Amy Birkinshaw --- Department of Nutrition and Dietetics (G24), South Africa Riette Nel --- Department of Biostatistics, South Africa Corinna Walsh --- Department of Nutrition and Dietetics (G24), South Africa

Background: Type 2 diabetes mellitus (T2DM) is considered to be the fastest growing chronic disease in the world and thus multi-sectoral, population-based strategies and approaches are needed to address the modifiable risk factors involved in the development and treatment of...

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Identifying phenological functional types in savanna trees

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Nthambeleni D Masia --- Council for Scientific and Industrial Research, Natural Resources and the Environment, South Africa Nicola Stevens --- Global Change and Biodiversity Group, Department of Botany and Zoology, South Africa Sally Archibald --- Council for Scientific and Industrial Research, Natural Resources and the Environment, South Africa

Savannas are notable for the varied patterns of leaf display in the tree layer. Characterising this variation, and assessing the range of phenological strategies apparent in savanna ecosystems will be helpful for understanding savanna tree life-histories and their response to...

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Silages in the form of diet based on spineless cactus and buffelgrass

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Alberto Jefferson da Silva Macêdo --- Department of Animal Science, Brazil Edson Mauro Santos --- Department of Animal Science, Brazil Gherman Garcia Leal de Araújo --- Embrapa Semi-arid, Brazil Ricardo Loiola Edvan --- Department of Animal Science, Brazil Juliana Silva de Oliveira --- Department of Animal Science, Brazil Alexandre Fernandes Perazzo --- Department of Animal Science, Brazil Wilma Cristina Cavalcante dos Santos Sá --- Department of Animal Science, Brazil Danillo Marte Pereira --- Department of Animal Science, Brazil

This study was conducted to evaluate the fermentation pattern and the in situ dry matter degradability of silages in the form of diet. Five diets were formulated based on spineless cactus (Opuntia fícus-indica cv. ‘Gigante’) and buffelgrass (Cenchrus ciliaris). The...

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Essential oil composition of Pentzia incana (Asteraceae), an important natural pasture plant in the Karoo region of South Africa

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Isabel M Hulley --- Department of Botany and Plant Biotechnology, South Africa Nicholas J Sadgrove --- Department of Botany and Plant Biotechnology, South Africa Patricia M Tilney --- Department of Botany and Plant Biotechnology, South Africa Gulmira Özek --- Department of Pharmacognosy, Faculty of Pharmacy, Turkey Suleyman Yur --- Medicinal Plant, Drug and Scientific Research Center, Turkey Temel Özek --- Department of Pharmacognosy, Faculty of Pharmacy, Turkey Kemal Hüsnü Can Başer --- Department of Pharmacognosy, Faculty of Pharmacy, Northern Cyprus Ben-Erik van Wyk --- Department of Botany and Plant Biotechnology, South Africa

Pentzia incana is one of the most important of all natural pasture plants in the dry interior (Karoo) region of South Africa. This highly aromatic shrub is thought to be responsible for the distinctive flavour of Karoo lamb (a registered...

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Design, construction and performance evaluation of a flat screen hammer mill machine

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: B. O. Ezurike --- Department of Mechanical Engineering, Nigeria O. J. Osazuwa --- Department of Mechanical Engineering, Nigeria C.A. Okoronkwo --- Department of Mechanical Engineering, Nigeria K.I. Okoji --- Department of Mechanical Engineering, Nigeria

The detailed design procedure for a hammermill machine is presented. The system designed is a modification to the conventional hammer mill with a circular bottom casing and a semi-circular screen. The major problems associated with the conventional machine are longer...

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Performance of Drought Tolerant Maize Varieties under Water Harvesting Technologies in the Coastal Region of Kenya

Item type: Journal Article • Journal: East African Agricultural and Forestry Journal • Authors: M.B. Muli --- Kenya Agricultural and Livestock Research Organization, Kenya D. Kengo --- Kenya Agricultural and Livestock Research Organization, Kenya A. Mzingirwa --- Kenya Agricultural and Livestock Research Organization, Kenya R. Musila --- Kenya Agricultural and Livestock Research Organization, Kenya

The average annual rainfall in coastal Kenya is 450–700 mm per annum in most places while the total annual evapotranspiration is 1200–1800 mm. In arid and semi-arid lands (ASALs), farmers grow maize varieties for medium to high rainfall zones without considering the...

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The bionomics of whitegrub species (Coleoptera: Scarabaeidae) affecting commercial forestry re-establishment in representative areas of the South African summer-rainfall region

Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Derian Echeverri-Molina --- Department of Biology, School of Science and Technology, Sefako Makgatho Health Sciences University, South Africa Prem Govender --- Research and Postgraduate Studies Directorate, Sefako Makgatho Health Sciences University, South Africa

South African commercial forestry plants mainly Eucalyptus, Pinus and Acacia species. Invertebrate pests play a significant role in the establishment phase of these exotic trees. Whitegrubs, in particular, are known to affect seedling survival during this period. Their pest status...

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A comparative analysis of the morphology and nutritive value of five South African native grass species grown under controlled conditions

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Khuliso E Ravhuhali --- Department of Animal Science, School of Agricultural Sciences, Faculty of Natural and Agricultural Sciences, South Africa Victor Mlambo --- School of Agricultural Sciences, Faculty of Agriculture and Natural Sciences, South Africa Tefera S Beyene --- Department of Livestock and Pasture Science, South Africa Lobina G Palamuleni --- Department of Geography and Remote Sensing, School of Environmental and Health Sciences, Faculty of Agriculture, South Africa

The comparative growth habits and nutritive value of native grass species of South Africa are largely unknown despite the utility of this information in rangeland restoration efforts. This article presents a comparative characterisation of the morphology, chemical composition and in...

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Communal farmers’ ecological knowledge and perceptions of grasses in the central Eastern Cape province, South Africa: similarities with field studies and scientific knowledge and their implications

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Solomon Tefera --- Department of Livestock and Pasture Science, South Africa Ayanda Kwaza --- Department of Livestock and Pasture Science, South Africa

The local ecological knowledge (LEK) and perceptions of grasses were investigated in six semi-arid communal areas in the central Eastern Cape province, South Africa, and compared with field studies and scientific knowledge. Of the total of 21 grasses identified in...

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Personality profiling of South African rugby union players

Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Ankebé Kruger --- Physical Activity, Sport and Recreation (PhASRec), South Africa Kobus Du Plooy --- Institute of Psychology & Wellbeing (IPW), North-West University, South Africa Pieter Kruger --- Institute of Psychology & Wellbeing (IPW), North-West University, South Africa

This study aimed to investigate whether differences exist in the personality profiles of professional and semi-professional rugby union players. Participants were 73 male rugby players, 52 professional players and 21 semi-professional players. All participants completed the NEO Five-Factor Personality Inventory...

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Patterns of juvenile reef-fish recruitment in Kenya’s shallow fringing- lagoon reefs

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: GM Okemwa --- Kenya Marine and Fisheries Research Institute, Kenya B Kaunda-Arara --- Department of Fisheries and Aquatic Sciences, Kenya EN Kimani --- Kenya Marine and Fisheries Research Institute, Kenya

Studies to understand local-scale patterns in the recruitment of juvenile coral-reef fishes within the western Indian Ocean (WIO) region are few, yet such knowledge is important in fisheries management. Underwater visual census surveys were conducted at five shallow fringing-lagoon reef...

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Vegetation dynamics in the face of a major land-use change: a 30-year case study from semi-arid South Africa

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Olli Hyvärinen --- FitzPatrick Institute of African Ornithology, DST/NRF Centre of Excellence, South Africa M Timm Hoffman --- Plant Conservation Unit, Department of Biological Sciences, South Africa Chevonne Reynolds --- FitzPatrick Institute of African Ornithology, DST/NRF Centre of Excellence, South Africa

Although wildlife production is widely considered beneficial for semi-arid environments, few studies have reported on the long-term environmental effects of converting from livestock production to game ranching. Asante Sana Game Reserve in South Africa was stocked with domestic livestock for...

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Ushairi Msemele na Ubidaa wa Euphrase Kezilahabi Katika Dhifa

Item type: Journal Article • Journal: Eastern African Literary and Cultural Studies • Authors: Ahmad Kipacha --- The Nelson Mandela African Institution of Science and Technology,

Euphrase Kezilahabi ameingia katika kundi la wabidaa wa kishairi ulimwenguni. Makala haya yanathibitisha hoja hiyo kupitia ushahidi wa ubunifu wa vipengele msemele katika diwani yake ya Dhifa (2008). Vipengele msemele vimechipuzwa ili kuwashawishi wasomaji wake wakubaliane na mabadiliko ya kifikra...

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A tale of two habitats: preliminary comparison of fish abundance and diversity between saltmarsh- and mangrove-dominated creeks in the Nahoon Estuary, South Africa

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Keur --- Department of Biodiversity and Conservation Biology, Faculty of Natural Science, South Africa N James --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa A Rajkaran --- Department of Biodiversity and Conservation Biology, Faculty of Natural Science, South Africa

A preliminary assessment of abundance and richness of fishes utilising saltmarsh and mangrove habitats in the Nahoon Estuary, situated on the eastern coast of South Africa, was undertaken during July 2017. The structural composition and complexity of the two habitats...

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Vulnerability of birds to contaminated water sources in the Karoo region of South Africa

Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Alan TK Lee --- FitzPatrick Institute of African Ornithology, South Africa Carolynne Geary --- Purposefully Lost Conservation Centre, South Africa Dale R Wright --- BirdLife South Africa, South Africa W Richard J Dean --- FitzPatrick Institute of African Ornithology, South Africa

The Karoo is a unique region in South Africa in terms of its ecological processes and endemic species. Large areas are needed to maintain viable populations of nomadic birds that follow erratic rainfall events and subsequent food and nesting resources,...

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Are type 2 diabetic patients meeting targets? A Helen Joseph Hospital Diabetic Clinic Audit

Item type: Journal Article • Journal: Journal of Endocrinology, Metabolism and Diabetes of South Africa • Authors: S Bulbulia --- Division of Diabetes, Endocrinology and Metabolism, Helen Joseph Hospital, F Variava --- Physician, Netcare Pinehaven Hospital, South Africa Z Bayat --- Division of Diabetes, Endocrinology and Metabolism and Department of Internal Medicine, Helen Joseph Hospital,

Background: The risk of complications from type 2 diabetes mellitus (T2DM) is high. Achieving targets reduces the morbidity and mortality. This study aims to assess whether patients at the Helen Joseph Hospital's Diabetic Clinic are meeting the 2012 SEMDSA targets...

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Compassion capability in resource-limited organizations in South Africa

Item type: Journal Article • Journal: Africa Journal of Management • Authors: Katherine J. Train --- Graduate School of Business, South Africa Kurt April --- Graduate School of Business, South Africa

Compassion in organizations benefits the giver and receiver of compassion, and the organization as a whole. Organizations with resource limitations, however, face risks and liabilities for compassion organizing. In South Africa, an emerging economy with a challenged socioeconomic environment, human...

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Macrobenthic community structure of the Mhlathuze Estuary, a permanently open estuarine embayment in KwaZulu-Natal, South Africa

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JI Izegaegbe --- Department of Zoology, South Africa L Vivier --- Department of Zoology, South Africa HMM Mzimela --- Department of Zoology, South Africa

The Mhlathuze Estuary, an estuarine embayment in northern Zululand, is considered an estuary of national conservation importance. No historical data on the benthic macrofauna are available for the past 20 years, creating a significant gap in our understanding of the...

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The influence of manual and motor-manual pitting implements, pit size and quality on eucalypt performance, South Africa

Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Ullrich Hechter --- , South Africa Keith M Little --- , South Africa Louis Titshall --- , South Africa

Pitting is the preparation of a planting position. Various methods of pitting exist and range from manual pitting to fully-mechanised operations. Until recently, most pit preparation in South Africa was carried out manually using hand-held pitting implements (agricultural hoe, mattock,...

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Interesting new facts on Heterodera schachtii (Nematoda: Heteroderidae) from South Africa

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Antoinette Swart --- , South Africa Rinus Knoetze --- , South Africa

In January 2017 Heterodera schachtii Schmidt, 1871 was collected from a potato field, formerly planted to cabbage, in the Tarlton area of South Africa. As H. schachtii from South Africa has never been studied molecularly, this short communication is the...

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Calibration and validation of APSIM–Maize, DSSAT CERES–Maize and AquaCrop models for Ethiopian tropical environments

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Hirut Getachew Feleke --- , South Africa MJ Savage --- , South Africa Kindie Tesfaye --- , Ethiopia

Process-based crop models are popular tools to quantify the impact of changes due to climate or crop management. Accurate simulation of crop production for different agro-ecological conditions using an individual crop model remains challenging due to different sources of uncertainty...

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Effects of atrazine on the endocrinology and histoarchitecture of the testes in African Catfish, Clarias gariepinus (Burchell, 1822)

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PA Opute --- , Nigeria IP Oboh --- , Nigeria JE Asouzu --- , South Africa N Pilani --- , South Africa EF Mbajiorgu --- , South Africa

Aquatic ecosystems often receive a wide spectrum of pollutants introduced directly or indirectly. The herbicide atrazine, an endocrine disrupting chemical (EDC), frequently contaminates potable water supplies and aquatic ecosystems. Studies suggest atrazine induced alterations in the neuroendocrine system along the...

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Determinants of digital commerce repeat-purchase behaviour in South Africa: A rural citizen perspective

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Vusani Netshirando --- , South Africa Willard Munyoka --- , South Africa Armstrong Kadyamatimba --- , South Africa

Digital commerce (d-commerce) has become a powerful tool for transforming marketplaces in emerging economies across the world. However, in South Africa, d-commerce, especially among the previously disadvantaged rural citizens, is still nascent. This study investigates the effect of facilitating conditions,...

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Effect of soil type on spatial distribution and nutritive value of grass species growing in selected rangelands of South Africa

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Khuliso E Ravhuhali --- , South Africa Victor Mlambo --- , South Africa Tefera S Beyene --- , South Africa Lobina G Palamuleni --- , South Africa

The distribution and status of grass species is essential for sustainable management of rangelands. Therefore, this study assessed the spatial distribution and nutritive value of grass species as influenced by soil type in selected rangelands of the North West province...

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Temporal and spatial variation of the molluscan community structure in Oualidia Lagoon, Moroccan Atlantic coast

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: F El Asri --- , Morocco A Errhif --- , Morocco MN Tamsouri --- , Morocco H Nhhala --- , Morocco M Maanan --- , France H Zidane --- , Morocco

The molluscan assemblages inhabiting the coastal waters of Oualidia Lagoon, Morocco, were studied during winter and summer of 2013. The taxonomic composition and diversity were determined at 43 sample sites. Thirty-four mollusc taxa were recorded in total, including 12 species...

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Analysis of effectiveness of channels for information gathering and dissemination: Case of fisheries stakeholders in Mwanza and Mara regions of Tanzania

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Sadiki Lameck Kusyama --- , Tanzania Dina Machuve --- , Tanzania Michael Kisangiri --- , Tanzania Abswaid Mfanga --- , Tanzania

The fisheries sub-sector in Tanzania is challenged with limited use of Information and Communication Technology (ICT) for information gathering and dissemination. Fishers obtain fisheries information from extension officers and their fellow fishers through mainly word of mouth in physical meetings...

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Predicted future changes in ocean temperature and pH do not affect prey selection by the girdled dogwhelk Trochia cingulata

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: N Martin --- , South Africa S Clusella-Trullas --- , South Africa TB Robinson --- , South Africa

Predator–prey relationships can drive community dynamics in marine systems, but it remains unclear how future changes in seawater temperatures and pH will influence these relationships. This study assessed the effect of predicted future temperatures and pH on the prey choice...

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The ecology of coastal wetland ponds created by diamond mining in southern Namibia. 2. Saltmarsh vegetation

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Maritz --- , South Africa D Pillay --- , South Africa GM Branch --- , South Africa

Diamond mining on the southern Namibian coastline has created multiple large coastal ponds of up to 380 000 m2 adjacent to the coastline, as the sea overtops erected seawalls or seeps into excavated areas. These ponds span ages of 1–38...

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Characterising epibenthic diversity and physical drivers in unconsolidated marine habitats of Algoa Bay, South Africa

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: HJ Truter --- , South Africa LJ Atkinson --- , South Africa CEO von der Meden --- , South Africa D Bailey --- , South Africa W Goschen --- , South Africa AT Lombard --- , South Africa

Unconsolidated marine sediment habitats spatially make up the majority of global ocean seabed, yet benthic faunal patterns and their abiotic drivers remain poorly understood. Benthic research in Algoa Bay, on the south coast of South Africa, has largely focused on...

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Weed species composition and abundance in the main coffee production systems and regions of Ethiopia

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Abera Daba --- , Ethiopia Mekuria Tadesse --- , Ethiopia Selamawit Negassa Chawaka --- , Ethiopia Gezahegn Berecha --- , Ethiopia

A weed population survey was carried out to assess the variability in weed species composition and abundance in the main coffee production systems and regions of Ethiopia. A total of 168 coffee fields were assessed using a quadrat count in...

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Aggregate dynamics and intra-aggregate carbon contents as influenced by long-term wheat production management in semi-arid South Africa

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: LS Tlomatsana --- , South Africa PF Loke --- , South Africa E Kotzé --- , South Africa MP Aghoghovwia --- , South Africa

Soil aggregate dynamics have received renewed interest due to their relevance in carbon (C) stabilisation. This study evaluated changes in aggregate-size distribution and intra-aggregate C following 41 years of wheat production in semi-arid central South Africa. Management practices that have...

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Abundance and distribution of plant-parasitic nematodes in tomatoes grown in a semi-arid agro-ecological zone in Tanzania

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Liberatus D Lyimo --- , Tanzania Jackline A Bakengesa --- , Tanzania Janeth D Mbuma --- , Tanzania

The abundance and distribution of plant-parasitic nematodes (PPN) on tomato plants grown in nine villages in the semi-arid zones of Singida and Dodoma in Tanzania were assessed in December 2020. Samples from soil and plant roots were evaluated for abundance,...

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The mediating role of ICT regulation on the effects of ICT access and ICT use on e-participation: Evidence from structural equation modelling and necessary condition analysis

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Ibrahim Osman Adam --- University for Development Studies, Ghana Muftawu Dzang Alhassan --- SD Dombo University of Business and Integrated Development Studies, Ghana

Recently, governments have been using information and communication technologies (ICTs) to provide platforms for citizen engagement and involvement through e-participation. This paper aims to explore the drivers behind e-participation in a global context. The discourse on e-participation in the information...

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Drivers of change in vegetation and soil in the Gamka Karoo: grazing versus rainfall

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: N Saayman --- , South Africa CD Morris --- , South Africa R Swart --- , South Africa JC Botha --- , South Africa

The Gamka Karoo is a low-lying vegetation type in the semi-arid Nama Karoo in the south-western part of South Africa with extensive rangelands used for livestock ranching and wildlife. Although the Nama Karoo is generally resilient to grazing and most...

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Curvature properties of metric and semi-symmetric linear connections

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Milo&scaron; Z. Petrović --- , Serbia Nenad O. Vesić --- , Serbia Milan Lj. Zlatanović --- , Serbia

Considering a non-symmetric linear connection and its dual one appear 6 independent curvature tensors [15]. In the present paper we study properties of curvature tensors of semi-symmetric metric connections on a generalized Riemannian manifold.

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The category of residuated lattice valued filter spaces

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Lin Zhang --- School of Mathematics and Statistics, Beijing Institute of Technology, China Bin Pang --- School of Mathematics and Statistics, Beijing Institute of Technology, China

Considering L as a complete residuated lattice, some further investigations on L-filter spaces are made. Firstly, it is shown that the category L-Fil of L-filter spaces is monoidal closed. Secondly, it is proved that the categories of L-Cauchy spaces and...

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Patterns of fish distribution in tropical rock pools at Príncipe Island, Gulf of Guinea

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J Azevedo e Silva --- University of Lisbon, Portugal AJ Almeida --- University of Lisbon, Portugal M Cravo --- University of Lisbon, Portugal MP Pais --- University of Lisbon, Portugal Y Santos --- , São Tomé e Príncipe J Paula --- University of Lisbon, Portugal

Little is known about the ichthyofauna from intertidal rock pools of the west coast of Africa, especially in the Gulf of Guinea. Rock pools are characteristic habitats of the intertidal zone of structurally complex rocky shores, adding important niche space...

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Perceived HIV/AIDS impact among staff in tertiary institutions in the Eastern Cape, South Africa

Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Nancy Phaswana-Mafuya --- Social Aspects of HIV/AIDS and Health, Human Sciences Research Council, Karl Peltzer --- Social Aspects of HIV/AIDS and Health, Human Sciences Research Council,

A descriptive questionnaire-based study was undertaken among staff in tertiary institutions in the Eastern Cape Province. The objective of the study was to explore perceived HIV/AIDS impact on duties at work, staff morale, job satisfaction and workload among a proportionate...

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Resources and infrastructure for the delivery of antiretroviral therapy at primary health care facilities in the Free State Province, South Africa

Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Ega Janse van Rensburg-Bonthuyzen --- Centre for Health Systems Research and Development, University of the Free State, Michelle Engelbrecht --- Centre for Health Systems Research and Development, University of the Free State, Francois Steyn --- Centre for Health Systems Research and Development, University of the Free State, Nandi Jacobs --- Centre for Health Systems Research and Development, University of the Free State, Helen Schneider --- Centre for Health Policy, University of Witwatersrand, Dingie van Rensburg --- Centre for Health Policy, University of Witwatersrand,

There are concerns as to whether South Africa's public health system has sufficient resources, human and otherwise, to ensure universal access to antiretroviral treatment (ART). We report on public sector implementation of the Comprehensive Care Management and Treatment (CCMT) programme...

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Policy-maker attitudes to the ageing of the HIV cohort in Botswana

Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Kabo Matlho --- , , Australia Refelwetswe Lebelonyane --- , Botswana Tim Driscoll --- , , Australia Joel Negin --- , , Australia

Background: The roll out of antiretroviral therapy in Botswana, as in many countries with near universal access to treatment, has transformed HIV into a complex yet manageable chronic condition and has led to the emergence of a population aging with...

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On the periphery of HIV and AIDS: Reflections on stress as experienced by caregivers in a child residential care facility in South Africa

Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Kesh Mohangi --- , , South Africa Chereen Pretorius --- , , South Africa

Few researchers have investigated how female caregivers of institutionalised children, especially those affected by HIV and AIDS, experience stress. The role played by caregivers cannot be overemphasised; yet caregivers who work in institutions caring for orphaned and/or abandoned children affected...

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A review of the African Elapsoidea semiannulata complex (Serpentes: Elapidae)

Item type: Journal Article • Journal: African Journal of Herpetology • Authors: DonaldG. Broadley --- ,

The status of the three subspecies of Elapsoidea semiannulata is reviewed on the basis of additional material. Typical E. s. semiannulata is extensively parapatric with both E. S. boulengeri and E. sundevallii fitzsimonsi in northeastern Namibia, with no sign of...

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Description of a new cryptic species of African sand frog, Tomopterna damarensis (Anura: Ranidae), from Namibia

Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: Abeda Dawood --- University of Pretoria, South Africa Alan Channing --- University of the Western Cape, South Africa

Sand frogs of the African genus Tomopterna Duméril and Bibron, 1841 comprise seven described cryptic species. In this paper we describe a new species from Khorixas, north west Namibia. It is considered a distinct form based on the advertisement call,...

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A new species of Arthroleptella Hewitt, 1926 (Anura: Ranidae) from the Groot Winterhoek mountains of the Western Cape province, South Africa

Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: AndrewA. Turner --- Western Cape Nature Conservation Board, South Africa AthertonL. de Villiers --- Western Cape Nature Conservation Board, South Africa Abeda Dawood --- University of Pretoria, South Africa Alan Channing --- University of the Western Cape, South Africa

A new species of Arthroleptella (moss frog), is described from the Groot Winterhoek Mountains in the Western Cape Province, South Africa. The new species is allopatric to other Arthroleptella species. It is distinguished from other Arthroleptella species by its advertisement...

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A new sand frog from central Tanzania (Anura: Ranidae: Tomopterna)

Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: Alan Channing --- University of the Western Cape, South Africa DavidC. Moyer --- Wildlife Conservation Society, Tanzania Abeda Dawood --- University of Pretoria, South Africa

A new species of sand frog in the genus Tomopterna is described from the highlands of south‐central Tanzania. It is distinguished from the other three species of sand frogs in East Africa on the basis of a low‐pitched advertisement call,...

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A new species of Arthroleptella Hewitt, 1926 (Anura: Pyxicephalidae) from the Klein Swartberg Mountain, Caledon, South Africa

Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: AndrewA. Turner --- Scientific Services, Western Cape Nature Conservation Board, South Africa Alan Channing --- University of the Western Cape, South Africa

A new species of moss frog (genus Arthroleptella) is described from the Klein Swartberg Mountain near Caledon in the Western Cape Province, South Africa to which it is confined. This allopatric species is distinguished from other Arthroleptella species by the...

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Within and between‐site distribution of frog species on the Udzungwa Plateau, Tanzania

Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: Lucinda Lawson --- University of Chicago, David Moyer --- Wildlife Conservation Society,

Amphibian distribution and abundance patterns are linked with environmental factors that define the suitable habitat for each species on both macro and micro scales. Determining the distribution and habitat requirements of species is a necessary first step in monitoring population...

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Spatial interpolation of vertisol physico-chemical properties through ordinary kriging in south-eastern Zimbabwe

Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Muketiwa Chitiga --- Lupane State University, Zimbabwe Gabriel Soropa --- Chinhoyi University of Technology, Zimbabwe Trevor Dube --- Midlands State University, Zimbabwe Progress Sengera --- GreenFuel, Zimbabwe

A decline in sugarcane yields from Block G (∼400 ha) of GreenFuel’s Chisumbanje Estate in south-eastern Zimbabwe prompted a study on spatial variability of the soil physico-chemical parameters in the 2017–2018 farming season. Using a systematic gridding schema, 123 geo-located...

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Global structure of positive solutions for semipositone nonlinear Euler-Bernoulli beam equation with Neumann boundary conditions

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Jingjing Wang --- Northwest Normal University, People’s Republic of China Chenghua Gao --- Northwest Normal University, People’s Republic of China Yanqiong Lu --- Northwest Normal University, People’s Republic of China

In this paper, we focus on the existence of positive solutions for nonlinear fourth-order Neumann boundary value problem

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Eliahou number, Wilf function and concentration of a numerical semigroup

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Patricio Almirón --- Universidad Complutense de Madrid, Spain Julio José Moyano-Fernández --- Departamento de Matemáticas & Institut Universitari de Matemátiques i Aplicacions de Castelló, Spain

We give an estimate of the minimal positive value of the Wilf function of a numerical semigroup in terms of its concentration. We describe necessary conditions for a numerical semigroup to have a negative Eliahou number in terms of its...

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R&D, innovations, and firms’ productivity in Ethiopia

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Mezid Nasir Keraga --- Addis Ababa University and Visiting Scholar at Jönköping University, Mesele Araya --- Addis Ababa University, Ethiopia

Evidence of how R&D, innovation and productivity are intertwined in African countries like Ethiopia is quite limited. This study provides empirical evidence on the relationship between R&D, innovations, and productivity for Ethiopian firms using two rounds of the World Bank’s...

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Nonlinear maps preserving semi-Fredholm operators with bounded nullity

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Guoxing Ji --- Shaanxi Normal University, People’s Republic of China Xia Jiao --- Shaanxi Normal University, People’s Republic of China Weijuan Shi --- Shaanxi Normal University, People’s Republic of China

Let be an infinite dimensional complex Banach space, and let be the algebra of all bounded linear operators on . In this paper, given any positive integer n, we provide a characterization of all bijective maps on preserving the diﬀerence...

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Cross-section measures, radii, and Radon curves

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Horst Martini --- University of Technology Chemnitz, Germany Zokhrab Mustafaev --- University of Houston-Clear Lake, USA

The purpose of this paper is to study cross-section measures and their connections to Radon curves in two-dimensional Minkowski spaces. More precisely, we use results on cross-section measures to present, for nomed planes, inner and outer radii of the unit...

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The complexity of a numerical semigroup

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: J.I. García-García --- Universidad de Cádiz, Spain M.A. Moreno-Frías --- Universidad de Cádiz, Spain J.C. Rosales --- Universidad de Granada, Spain A. Vigneron-Tenorio --- Universidad de Cádiz, Spain

Let S and Δ be numerical semigroups. A numerical semigroup S is an I(Δ)-semigroup if S \ {0} is an ideal of Δ. We denote by S is an I(Δ)-semigroup}, and we say that Δ is an ideal extension...

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L ω 1 -invariant weighted Orlicz spaces

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: AliReza Bagheri Salec --- University of Qom, Iran Seyyed Mohammad Tabatabaie --- University of Qom, Iran

In this paper, we prove that σ-compactness of a locally compact group G is a necessary condition for the weighted Orlicz space to be a convolution algebra, and for a class of Orlicz spaces we give an equivalent condition. Also,...

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Seedling establishment and early growth in Calobota sericea subjected to moisture stress

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Francuois Müller --- , South Africa Letty Masemola --- , South Africa Stephen Modiba --- , South Africa Nothando Ngcobo --- , South Africa

The South African perennial legume Calobota sericea (Thunb.) Boatwr. & B-E van Wyk has been shown to be drought tolerant as mature plants, but information on drought tolerance of seedlings is lacking. This study evaluated the impact of moisture stress...

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Approximate controllability of non-instantaneous impulsive semi-linear neutral differential equations with non-local conditions and unbounded delay

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Oscar Camacho --- Universidad San Francisco de Quito USFQ, Ecuador S. Lalvay-Segovia --- , Ecuador Hugo Leiva --- , Ecuador L. Riera-Segura --- , Ecuador

In this work, we study the approximate controllability for retarded neutral diﬀerential equations with unbounded delay, non-instantaneous impulses, and non-local conditions. First, we set the problem in a natural Banach phase space satisfying Hale-Kato axiomatic Theory about the phase space...

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Universal specialization semilattices

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Paolo Lipparini --- Università di Roma “Tor Vergata”, Italy

A specialization semilattice is a structure which can be embedded into , where X is a topological space, x ⊑ y means x ⊆ Ky, for x, y ⊆ X, and K is closure in X. Specialization semilattices and posets...

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Haagerup property of semigroup crossed products

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Qing Meng --- Qufu Normal University, China

In this paper, we study the Haagerup property of semigroup crossed products for lattice ordered groups. Let G be a lattice ordered group. We show that the reduced semigroup C*-algebra C*r (G +) has the Haagerup property if and only...

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Equidivisibility and profinite coproduct

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Jorge Almeida --- Universidade do Porto, Portugal Alfredo Costa --- University of Coimbra, Portugal

The aim of this work is to investigate the behavior of equidivisibility under coproduct in the category of pro-V semigroups, where V is a pseudovariety of finite semigroups. Exploring the relationship with the two-sided Karnofsky-Rhodes expansion, the notions of KR-cover...

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An analysis of pre-recorded street audio adverts in Zimbabwe: A dariro perspective

Item type: Journal Article • Journal: South African Journal of African Languages • Authors: Tevedzerai Gijimah --- Literature and Cultural Studies, Midlands State University, Zimbabwe Charles Tembo --- University of South Africa, South Africa

Street vending has become the order of the day in Zimbabwe. Because of the popularity of vending, vendors have come up with various ways of making their goods visible in a highly populated market. Audio advertising is one of the...

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Some concepts of topology and questions in topological algebra

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: A.V. Arhangel’skii --- Moscow Pedagogical State University, Russia

This paper has features of mixed nature. It contains new results, in particular, on semitopological groups. We also pose some problems, introduce new definitions and describe in details certain techniques we need below, providing the proofs of not so well-known...

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Epimorphisms and closure operators of categories of semilattices

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: D. Dikranjan --- Università degli Studi di Udine, Italy A. Giordano Bruno --- Università degli Studi di Udine, Italy N. Zava --- Institute of Science and Technology Austria (ISTA),

Motivated by a problem posed in [10], we investigate the closure operators of the category SLatt of join semilattices and its subcategory SLatt O of join semilattices with bottom element. In particular, we show that there are only finitely many...

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Some properties of conjunctivity (subfitness) in generalized settings

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: M. Andrew Moshier --- CECAT, Chapman University, USA Jorge Picado --- University of Coimbra, Portugal Ale&scaron; Pultr --- Charles University, Czech Republic

The property of subfitness used in point-free topology (roughly speaking) to replace the slightly stronger T 1-separation, appeared (as disjunctivity) already in the pioneering Wallman’s [16], then practically disappeared to reappear again (conjunctivity, subfitness), until it was in the recent...

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On ωs-balanced semitopological groups

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Vikesh Kumar --- University of Delhi, India Brij Kishore Tyagi --- Atma Ram Sanatan Dharma College, University of Delhi, India

In this paper we introduce the notion of ωs-balanced semitopological groups. We show that a regular (Hausdorff, T 1) semitopological group G admits a homeomorphic embedding as a subgroup into a product of regular (Hausdorff, T 1) semitopological groups with...

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Argument mining from Amharic argumentative texts using machine learning approach

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Mikru Lake Melie --- Jimma University, Jimma Institute of Technology, Ethiopia Debela Tesfaye --- Jimma University, Jimma Institute of Technology, Ethiopia Alemu Kumilachew Tegegnie --- Bahir Dar University, Bahir Dar Institute of Technology, Ethiopia Derejaw Lake Melie --- Bahir Dar University, Bahir Dar Institute of Technology, Ethiopia

Argument mining is an emerging science that deals with the automatic identification and extraction of arguments along with their relation from large, unstructured data that are useful for reasoning engines and computational models. Identification and extraction of argument relation from...

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Quantifying the effect of chemical bush control of Senegalia mellifera on vegetation production in the Eastern Kalahari Bushveld, South Africa

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: --- , South Africa --- , South Africa --- North-West University, South Africa

Bush encroachment is the invasion of whole landscapes by indigenous and alien woody species. An imbalance in the ratio of grasses to bushes is a consequence of bush encroachment due to competition for moisture, nutrients and sunlight. This imbalance results...

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Extension of semi-Lipschitz maps on non-subadditive quasi-metric spaces: new tools for Artificial Intelligence

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Roger Arnau --- Instituto Universitario de Matemática Pura y Aplicada, Universitat Politècnica de València, Spain Natalia Jonard-Pérez --- Universidad Nacional Autónoma de México, México Enrique A. Sánchez Pérez --- Instituto Universitario de Matemática Pura y Aplicada, Universitat Politècnica de València, Spain

The axioms of symmetry and indiscernibility of a metric function can be eliminated and still define a topological space with good enough properties. However, among all the axioms that constitute the notion of a metric, the subadditivity or triangular inequality...

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Order boundedness and order continuity properties of positive operator semigroups

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Jochen Glück --- University of Wuppertal, School of Mathematics and Natural Sciences, Germany Michael Kaplin --- Institute of Mathematics, Slovenija

Relatively uniformly continuous (ruc) semigroups were recently introduced and studied by Kandic, Kramar-Fijavž, and the second-named author, in order to make the theory of one-parameter operator semigroups available in the setting of vector lattices, where no norm is present in...

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Advertisement call description of the exceedingly rare Phrynomantis affinis (Anura: Microhylidae), with comparisons to P. bifasciatus and range extensions for both species

Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Francois S Becker --- National Museum of Namibia, Namibia Alan Channing --- North-West University, South Africa

Despite a relatively broad distribution in Africa, the Spotted Rubber Frog, Phrynomantis affinis, is extremely rarely encountered. Only 18 specimens from 12 localities have been collected with a few additional observations recorded. Virtually nothing of the species’ natural history is...

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A new bullfrog from southern Africa (Pyxicephalidae, Pyxicephalus Tschudi, 1838)

Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Louis H du Preez --- North-West University, South Africa Edward C Netherlands --- North-West University, South Africa Mark-Oliver Rödel --- , Germany Alan Channing --- North-West University, South Africa

Four species of African bullfrogs are currently recognised. We describe a new species from southern Africa, which can be distinguished on the basis of morphology, advertisement call and DNA sequences. Morphologically it differs from other bullfrogs by a combination of...

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Health provider administration functions, patient satisfaction, and loyalty: Their mediation by patient healthcare service quality perceptions

Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Geoffrey Bentum-Micah --- Zhejiang Normal University, China Lianyu Cai --- Zhejiang Normal University, China Sampson Agyapong Atuahene --- Zhejiang Normal University, China Moses Agyemang Ameyaw --- Zhejiang Normal University, China Victor Bondzie-Micah --- Hong Kong Baptist University, Hong Kong Stephen Sarfo Adu-Yeboah --- Hefei University of Technology, China

The study tested a health service quality mediation model on patient satisfaction and loyalty outcomes with provider administration functions. Participants were 7 108 outpatients from eleven public hospitals in Hubei province, China (female = 58.5%; infections and chronic diseases =...

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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, Tunisia

In 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].

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Concircularly semi-symmetric metric connection

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Miroslav D. Maksimović --- University of Pri&scaron;tina in Kosovska Mitrovica, Serbia Milo&scaron; Z. Petrović --- University of Ni&scaron;, Serbia Nenad O. Vesić --- Mathematical Institute of Serbian Academy of Sciences and Arts, University of Belgrade, Milan Lj. Zlatanović --- University of Ni&scaron;, Serbia

Results on a concircularly semi-symmetric metric connection on a Riemannian manifold are presented. Six linearly independent curvature tensors with respect to this non-symmetric linear connection are studied, and the tensors coincident with the Weyl projective curvature tensor and the concircular...

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$Stability analysis of fully dynamic piezoelectric beams with internal fractional delay$

Stability analysis of fully dynamic piezoelectric beams with internal fractional delay

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Jianghao Hao --- Shanxi University, P.R. China Jing Yang --- Shanxi University, P.R. China

In this paper, we are interested in the stability analysis of one-dimensional fully dynamic piezoelectric beam systems with internal fractional delay under different feedback controls (boundary and internal). By introducing two new equations to deal with fractional delay, equivalent new...

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Subgroups of products of semitopological groups with a strong development

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Iván Sánchez --- Universidad Autónoma Metropolitana,

Using the notion of ωs-balanced semitopological group and some cardinal invariants, Kumar and Tyagi [7] characterize when a regular (T 1, Hausdorff) semitopological group admits a homeomorphic embedding as a subgroup into a product of regular (T 1, Hausdorff) semitopological...

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Vacillating vaccines: responses to Covid-19 in the United States and South Africa

Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: Theodore Powers --- Anthropology, University of Iowa, United States of America Jimmy Pieterse --- University of Pretoria, South Africa

This article examines the internal pathways of disease transfer within two settler colonies, the United States and South Africa, whilst also considering points of transnational connection in the social, political, epidemiological, religious and cultural responses to the Covid-19 pandemic in...

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Species diversity and distribution-pattern determinants of African rivulines (Cyprinodontiformes: Nothobranchiidae) in rainforest streams of southern Cameroon

Item type: Journal Article • Journal: African Zoology • Authors: FD Messu Mandeng --- Higher Teacher’s Training College (ENS), University of Yaoundé I, Cameroon CF Bilong Bilong --- University of Yaoundé I, Cameroon JF Agnese --- University of Montpellier (CNRS, IRD, EPHE), France

Understanding the community structure and ecology of fish populations in rainforest streams is a prerequisite for any actions towards their exploitation, management or conservation. We examined the community structure and species diversity of nothobranchiids (African rivulines) in rainforest streams of...

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Generalized derivations with nilpotent values in semiprime rings

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Cheng-Kai Liu --- National Changhua University of Education, Taiwan

Let R be a (semi-) prime ring with extended centroid C, let f(X 1, … , Xk ) be a multilinear polynomial over C in k noncommutative indeterminates which is not central-valued on R and let g be a generalized derivation of...

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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, Tunisi

Let 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...

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Spatial patterns and environmental drivers of demersal fish assemblages in the Swartkops and Sundays estuarine to marine seascapes, South Africa

Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: P Nodo --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa AR Childs --- Rhodes University, South Africa P Pattrick --- Nelson Mandela University, South Africa NC James --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa

Estuaries are often observed as the boundary between the ocean and the river, separating coastal environments, rather than being seen as a continuum. Owing to insufficient research on demersal fish communities across nearshore marine to estuarine habitats, particularly in South...

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On bi-continuous cosine families

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Christian Budde --- University of the Free State, South Africa

In this article, we introduce and investigate bi-continuous cosine families. Those are inspired by the theory of bi-continuous semigroups which had an impact in the area of evolution equations in the last decades. The idea here is again that we...

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Killing tsetse and/or saving wildlife? A multispecies assemblage in colonial Zambia (1895–1959)

Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: Léa Lacan --- University of Cologne, Germany

This article investigates the problem of the tsetse fly and the trypanosomiasis disease it conveys as a transforming multispecies assemblage in colonial Zambia from the late nineteenth century until 1959. Based on archival research, it analyses the tsetse fly (Glossina...

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A lemma on C ₀-semigroups on time scales and approximate controllability of the heat dynamic equation

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Martin Bohner --- Missouri University of Science and Technology, USA Cosme Duque --- Universidad de Los Andes, Hugo Leiva --- University YachayTech, School of Mathematical and Computational Sciences, Ecuador Zoraida Sivoli --- Universidad Siglo 21,

In this paper, we present a lemma that allows us to characterize a broad class of C 0-semigroups on time scales, which can be applied to prove existence and uniqueness of solutions of systems of partial differential equations where the...

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Subgroups of products of Nagata semitopological groups and related results

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Liang-Xue Peng --- Beijing University of Technology, China

In this article, we introduce notions which are called property (c*) and property (M 3*) for semitopological groups. We show that if G is a regular semitopological group with a q-point, property (c*) and Sm(G) ≤ ω, then G is...

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A construction of the assembly of a frame

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Richard N. Ball --- University of Denver, U.S.A

We offer here a particularly simple and direct construction of the congruence frame of a given frame, aka its assembly, from the bounded meet semilattice of differences of frame elements. The construction enables economical proofs of two of the assembly’s...

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Examining cryptocurrency usage by technology acceptance model in the Turkish context

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Asli Derlek Kocabas --- Yalova University, Turkiye Eyup Calik --- Yalova University, Turkiye Basak Cetinguc --- Yalova University, Turkiye

In recent times, the usage of cryptocurrencies has become remarkably widespread in e-commerce applications. This study aims to explain the factors affecting cryptocurrencies by proposing an extended technology acceptance model (TAM) consisting of perceived ease of use, perceived usefulness, trust,...

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Weaving the tastes of tradition: Uncovering the threads of India’s culinary identity amid globalisation

Item type: Journal Article • Journal: Research in Hospitality Management • Authors: Ha van Trung --- Graduate Institute of Tourism Management, National Kaohsiung University of Hospitality and Tourism, Taiwan Du Quoc Dao --- Van Hien University, Vietnam

In the face of globalisation’s homogenising wave, this study serves as a beacon, illuminating the intricate web of factors that safeguard culinary heritage in India. The study hypothesised that a myriad of elements interweaves to form the fabric of food...

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Semi-c-periodicity, c-uniform recurrence and almost automorphy in the complex plane

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: H. Ounis --- University of Alicante, Spain J.M. Sepulcre --- University of Alicante, Spain

This paper is devoted to develop the concepts of semi-c-periodicity, c-uniform recurrence and almost automorphy for functions defined on vertical strips in the complex plane, where c is a non-zero complex number. As an extension of the study performed for...

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On variants and generalizations of J-frames

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Siyabonga S. Dubazana --- University of KwaZulu-Natal, S.A. Simo S. Mthethwa --- University of KwaZulu-Natal, S.A.

A J-frame is a pointfree topology counterpart of the concept of a J-space. In this paper, we present a study of some frames satisfying conditions that are stronger (and some that are weaker) than those defining J-frames. Conditions under which...

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On z-ideals and z-closure operations of semirings, I

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Amartya Goswami --- University of Johannesburg, South Africa

The aim of this series of papers is to study z-ideals of semirings. In this article, we introduce some distinguished classes of z-ideals of semirings, which include z-prime, z-semiprime, z-irreducible, and z-strongly irreducible ideals and study some of their properties...

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The extended Frobenius problem for Lucas series incremented by a Lucas number

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Aureliano M. Robles-Pérez --- Universidad de Granada, Spain José Carlos Rosales --- Universidad de Granada, Spain

We study the extended Frobenius problem for sequences of the form {la } ∪ {la + ln } n∈N and {la + ln } n ∈N , where {ln } n∈N is the Lucas series and la is a...

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Antagonistic aria: vocalisations of the male slender feather-tailed leaf-toed gecko (Gekkonidae: Kolekanos plumicaudus)

Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Francois S Becker --- National Museum of Namibia, Ministry of Education, Arts and Culture, Namibia Pedro Vaz Pinto --- CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Laboratório Associado, Universidade do Porto, Portugal Javier Lobón-Rovira --- CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Laboratório Associado, Universidade do Porto, Portugal

Kolekanos plumicaudus is a gecko endemic to the Namib Desert in south-western Angola. It is distantly related to all other geckos in the region, except for its one congener, K. spinicaudus. There have been no scientific accounts on the social...

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Context is key: Using intersectionality and sensemaking to unlock new doors in leadership theory

Item type: Journal Article • Journal: Africa Journal of Management • Authors: Clif P Lewis --- Queen Mary University of London, UK

This research explores differences in how marginalized groups in leadership roles within the South African private sector engage in sensemaking, influenced by intersecting gender and race identities. Primary data was collected with semi-structured intersectional interviews. Thematic and axial coding was...

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Ukucobelelana ngolwazi olungamagugu ase-Afrika lwesenzo ‘goma’ olusemyalezweni osenkundleni yezokuxhumana iTikTok

Item type: Journal Article • Journal: South African Journal of African Languages • Authors: Beryl Babsy Boniwe Xaba --- University of South Africa, South Africa

Sekube nokukhalaza okuningi ngokubhalwa kolimi ezinkundleni zokuxhumana. Izingcweti zolimi kanye nabacwaningi bolimi abagculisekile ngokusetshenziswa kolimi kulezi zizindalwazi. Isililo esikhulu sisuswa ukungayilandeli imigomo nemithetho yolimi lwesiZulu uma kubhalwa ezinkundleni zokuxhumana. Lolu cwaningo luhlose ukwethula indlela inkundla yezokuxhumana iTikTok efundisa ngayo ngemvelaphi...

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Nominalisation and semantic shift in selected isiXhosa nouns

Item type: Journal Article • Journal: South African Journal of African Languages • Authors: Andiswa Mvanyashe --- Nelson Mandela University, South Africa

This study addresses the process of nominalisation in isiXhosa to establish its historical development and implications on the writing and sense of words. Nominalisation, an important feature of scientific writing, enables information concentration as well as grammatical functions such as...

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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, Jordan

In 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,...

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Spatial environmental variability shapes the diversity of bottom ecosystems on the western Gulf of Guinea shelf

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Denechaud --- Institute of Marine Research (IMR), Norway E Dovlo --- Fisheries Scientific Survey Division (FSSD), Ghana T Joanny --- Centre de Recherches Océanologiques (CRO), Côte d’Ivoire VS Osei --- Fisheries Scientific Survey Division (FSSD), Ghana L Buhl-Mortensen --- Institute of Marine Research (IMR), Norway A Staby --- Institute of Marine Research (IMR), Norway

The western Gulf of Guinea is characterised by seasonal upwellings and hosts a large diversity of marine species. Although the assemblages of bottom fishes and benthic organisms are periodically assessed, there has been little research investigating these in tandem. We...

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Ethnic community languages in contemporary social media advertisements in Tanzania

Item type: Journal Article • Journal: South African Journal of African Languages • Authors: Emmanuel Ilonga --- Dar es Salaam University College of Education (DUCE), Tanzania

A speech community’s expectation is to see its language develop. However, such an imaginative prospect may not materialise due to the asymmetrical power dynamics between influential and less influential speech communities. Consequently, less influential societies are forced to depend on...

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Semantic extensions of ziyakhala used on social media platforms in South Africa

Item type: Journal Article • Journal: South African Journal of African Languages • Authors: Yanga Lusanda Praiseworth Majola --- Tshwane University of Technology, South Africa Evangeline Bonisiwe Zungu --- University of Johannesburg, South Africa

This study analyses the semantic extension ziyakhala (also written as ayikhale or azikhale), which is popularly used on social media platforms. Ziyakhala literally means ‘let it cry’, the root word is ‘khala’ which means to cry and the prefix ‘zi’...

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Generalized A-numerical radius inequalities in semi-Hilbert spaces through the angle between two vectors

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Mojtaba Bakherad --- University of Sistan and Baluchestan, Iran

This paper presents several inequalities related to the A-numerical radius in the context of semi-Hilbert space operators. By integrating modern techniques from operator theory and functional analysis, we derive new inequalities for the A-numerical radius that emphasize the unique characteristics...

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Further remarks on z-ideals of semirings

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Amartya Goswami --- University of Johannesburg, South Africa Ahmed Maatallah --- University of Monastir, Faculty of Sciences of Monastir, Research Laboratory on Algebra, Tunisia

In this note, we revisit certain results from a previous work of the first author concerning z-ideals of semirings. We demonstrate that the assumption of the semiring being a bzi-semiring can be dispensed with. Additionally, we propose a revised definition...

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Nil Modules and the Envelope of a Submodule

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: David Ssevviiri --- Makerere University, Uganda Annet Kyomuhangi --- Busitema University, Uganda

Let R be a commutative unital ring and N be a submodule of an R-module M. We show that: 1) the semiprime radical is an invariant on submodules generated by the ascending chain of envelopes of a given submodule; 2)...

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Approximate controllability of a parabolic dynamic equation on homogeneous time scales

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Martin Bohner --- Missouri University of Science and Technology, USA Cosme Duque --- Universidad de Los Andes, Hugo Leiva --- University YachayTech, School of Mathematical and Computational Siences, San Miguel de Urcuqui, Ecuador

This paper aims to explore the approximate controllability of a semilinear system of parabolic dynamic equations on homogeneous time scales. Building on the innovative semigroup theory for time scales introduced in [13], we leverage a pivotal lemma from [5] that...

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Lexical borrowing and semantic changes in the Chasu speech community of Tanzania

Item type: Journal Article • Journal: South African Journal of African Languages • Authors: Rafiki Yohana Sebonde --- University of Dodoma, Tanzania

In Same District, Kilimanjaro, in Tanzania, there is a long-lasting contact situation with Chasu, Kiswahili and English languages. As a result, Chasu has frequently borrowed new terms and concepts from Kiswahili and English. Other studies on Chasu have concentrated on...

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Exploring polysemy and its role in lexical sense relations in African languages: Insights from African Wordnet

Item type: Journal Article • Journal: South African Journal of African Languages • Authors: Stanley Madonsela --- University of South Africa, South Africa

Polysemy has been considered in terms of sense relations where each sense of a polysemous expression is represented individually in the lexicon. Siswati and other African languages accounted for in African Wordnet do not differ in the characterisation of this...

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Blockchain technology in healthcare within the global south: mapping the area and developing a research scenario

Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Josue Kuika Watat --- University of Oslo, Norway Ebenezer Agbozo --- Ural Federal University, Russia Rania El-Gazzar --- University of Agder, Norway

Africa’s healthcare systems face profound structural challenges, including fragmented infrastructure, systemic data vulnerabilities, and unreliable medical supply chains, necessitating innovative, context-specific solutions. Blockchain technology has emerged as a transformative tool in global healthcare, yet research remains disproportionately focused on high-income...

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A Portuguese urban vegetable garden under the gaze of hospitality

Item type: Journal Article • Journal: Research in Hospitality Management • Authors: Cynthia Luderer --- Social Sciences Institute, University of Minho, Portugal

This work concerns an urban vegetable garden in the north-west of Portugal and aims to describe the hospitality surrounding this environment. This study resulted from a two-year field investigation, which was methodologically driven by ethnography and supported by the anthropology...

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An assessment of heavy metal accumulation in the Vaal River system, South Africa, using artificial mussels

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JA Calaca --- University of the Witwatersrand, South Africa S Dahms-Verster --- University of the Witwatersrand, South Africa

This study aims to identify metal concentrations around the Vaal River system by means of spot water sampling and the use of artificial mussels (AMs). Levels of Al, Cd, Co, Cr, Cu, Fe, Mn, Pb and Zn were determined at...

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Pastoralist knowledge and perceptions on land degradation and forage diversity loss: a case study in the Bordj Bou Arreridj semi-arid region, Algeria

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Lounis Semara --- Mohamed El Bachir El Ibrahimi University of Bordj Bou Arreridj, Algeria Sofiane Bensefia --- Mohamed El Bachir El Ibrahimi University of Bordj Bou Arreridj, Algeria Farida Belkasmi --- Mohamed El Bachir El Ibrahimi University of Bordj Bou Arreridj, Algeria Charefeddine Mouffok --- Ferhat Abbas Setif 1 University, Algeria Abdelaziz Bouzegag --- University Centre of Mila, Algeria

This study assessed the level of knowledge and perception of pastoralists in the Bordj Bou Arreridj zone in the semi-arid region of Algeria regarding pastureland degradation and loss of forage species diversity. Through group discussions and field surveys, 100 pastoralists...

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Simulated rangeland conditions and seasonal variations influence soil quality in semi-arid central South Africa

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: JDJ Marx --- University of the Free State, South Africa E Kotzé --- University of the Free State, South Africa JJ van Tol --- University of the Free State, South Africa PF Loke --- University of the Free State, South Africa

The study examined long-term effects of rangeland conditions and seasonal variations on soil quality without confounding grazing effects. Samples were collected seasonally from good, moderate, poor, bare and cultivated rangeland conditions at soil depths of 0–10 cm and analysed for...

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Numerical semigroups of coated odd elements

Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: M.B. Branco --- Universidade de Évora, J.C. Rosales --- Universidad de Granada, Spain M.A. Traesel --- Instituto Federal de São Paulo, Brazil

A numerical semigroup S is coated with odd elements (Coe-semigroup), if {x − 1, x + 1} ⊆ S for all odd elements x in S. In this note, we will study this kind of numerical semigroup. In particular, we...

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Transhumance within private land conservation areas: perspectives from pastoralist landowners in rural Kenya

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Simon M Thiong’o --- Centre for Events, Tourism, and Hospitality Management, Carnegie School of Sport, Leeds Beckett University, Headingley Campus, UK

Pastoralism in Kenya’s arid and semi-arid regions supports about 10 million indigenous people. While general studies on pastoralist livelihoods exist, limited research explores these dynamics within privately governed landscapes. This study critically examines how land tenure complexities within private land...

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Daily herd movements across the wet and dry season in the semi-arid communal rangelands of Namaqualand, South Africa

Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: MH Tapela --- Department of Biodiversity and Conservation Biology, University of the Western Cape, South Africa MI Samuels --- Department of Biodiversity and Conservation Biology, University of the Western Cape, South Africa CF Cupido --- ARC–Animal Production (Range and Forage Sciences), South Africa A Finca --- ARC–Animal Production (Range and Forage Sciences), South Africa TC Zondani --- ARC–Animal Production (Range and Forage Sciences), South Africa A Engelbrecht --- Department of Biodiversity and Conservation Biology, University of the Western Cape, South Africa

The role of indigenous grazing management practices in sustainable natural resource use has been widely identified and recognised in the literature. However, the grazing management practices of Nama pastoralists in the semi-arid regions in Namaqualand in South Africa have not...

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Distribution and community structure of riverine fish in two east-flowing rivers in Kenya

Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Japhet Kaadzo Tembo --- Egerton University, Kenya Charles Maina Kihia --- Egerton University, Kenya Nzula Kivuva Kitaka --- Egerton University, Kenya Gordon O’Brien --- School of Biology and Environmental Sciences, University of Mpumalanga, South Africa Emmanuel Mbaru --- , Malaysia Catherine Kariuki --- Egerton University, Kenya

This study investigated the distribution, composition and habitat associations of freshwater eels in the Athi–Galana–Sabaki (Athi) and Ramisi Rivers using fortnightly fyke-net sampling conducted between April 2021 and March 2022. A total of 304 eels were recorded, with the Ramisi...

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