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A slope sequence of Podzols in the southern Cape, South Africa 1. Physical and micromorphological properties
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: L.C. Hawker --- Department of Geography, South Africa T.H. van Rooyen --- Department of Geography, South Africa R.W. Fitzpatrick --- Department of Geography, South AfricaIn South Africa the characteristics of Podzols, with or without placic horizons, and the complex processes involved in their formation, are generally still poorly understood. To investigate both these aspects thoroughly, these soils were studied in the landscape context, described... -
ON THE DISSOLVED SOLIDS OF THE PONGOLO FLOOD PLAIN PANS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J. Heeg --- Pongolo Research Group, C.M. Breen --- Pongolo Research Group, P.M. Colvin --- Pongolo Research Group, H.D. Furness --- Pongolo Research Group, C.F. Musil --- Pongolo Research Group,The water retained in the Pongolo flood plain pans differs from that of the Pongolo River not only in having a higher TDS, but also in the composition of the solutes, which approximate to seawater in their equivalent ionic proportions... -
BATHYMETRIC STUDIES ON THE PONGOLO RIVER FLOODPLAIN
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: C.M. Breen --- Pongolo River Research Group, Departments of Botany, South Africa H.D. Furness --- Pongolo River Research Group, Departments of Botany, South Africa J. Heeg --- Pongolo River Research Group, Departments of Zoology, South Africa J. Kok --- Pongolo River Research Group, Departments of Zoology, South AfricaThirteen of the major pans on the Pongolo river floodplain have been studied. Most are shallow (>2.5 m) and regularly lose up to 70% of their water each year, although few dry out. Floods inundate considerable areas (1000 ha) around... -
Afromontane forest avifauna of the eastern Soutpansberg mountain range, Northern Province, South Africa
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: C.T. Symes --- , South Africa S.M. Venter --- Department of Water Affairs and Forestry, South Africa M.R. Perrin --- , South AfricaThe Soutpansberg forests form the northern limit of indigenous forest in South Africa, Commercial afforestation occurs at high altitudes whereas crops and orchards are planted at lower altitudes. A study of five protected afromontane forests in the eastern Soutpansberg identified... -
A Matching Technique and Structure Theorems for Sturm-liouville Boundary Value Problems with Interior Singularities
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: ThomasM. AchoAsymptotic solutions for the interior double pole Sturm-Liouville boundary value problem are obtained using a method of matched asymptotic approximations. Employing asymptotic forms of the Whittaker functions, the WKB approximations and Airy functions, solutions are obtained valid and non-vanishing on... -
The number of elements close to near-records in geometric samples
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Guy Louchard Helmut ProdingerThe statistics of interest here are related to an independent sequence of geometrically distributed random variables. We look at the (n − k)th order statistic (=(k + 1)st winner) and study the number of elements that fall exactly a away... -
Plant traits and spread of the invasive salt marsh grass, Spartina alterniflora Loisel., in the Great Brak Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JB Adams --- Department of Botany, South Africa A Grobler --- Department of Botany, South Africa C Rowe --- Department of Botany, South Africa T Riddin --- Department of Botany, South Africa TG Bornman --- , South Africa DR Ayres --- Evolution and Ecology, USASpartina alterniflora Loisel., widely recognised as an aggressive invader of estuaries and salt marshes around the world, was discovered growing in the temporarily open/closed Great Brak Estuary on the southern Cape coast of South Africa in 2004. This is the... -
Solar Energy Industry Future Uncertainty – An Opportunity for New Markets and Refocusing
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Hattie Carwell --- , USAThe 2012 solar panel pricing war between manufacturers in China, Europe and the USA, accompanied by the sales market slowdown due to government subsidy cuts, has produced uncertainty in the future of the growth of the solar industry. A solar... -
Recent distributional changes of seabirds in South Africa: is climate having an impact?
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RJM Crawford AJ Tree PA Whittington J Visagie L Upfold KJ Roxburg AP Martin BM DyerThere have been recent changes in the distributions of several seabirds in South Africa. In the mid-1990s, breeding of Leach's storm petrel Oceanodroma leucorhoa was recorded in the Western Cape, the first record for the Southern Hemisphere. There was a... -
Re-expansion pulmonary oedema after evacuation of iatrogenic tension pneumothorax: a case report
Item type: Journal Article • Journal: Southern African Journal of Anaesthesia and Analgesia • Authors: S Goel --- Department of Anesthesiology and Intensive Care, India B Singh --- Department of Anesthesiology and Intensive Care, IndiaA 20- year male, ASA physical status grade I, was operated on for a duodenal fistula. The intra- and postoperative periods were uneventful. 10 days later, the right internal jugular catheter was substituted with a triple lumen catheter in the... -
The occurrence of large branchiopod crustaceans in perennial pans: a research note
Item type: Journal Article • Journal: African Zoology • Authors: M. Ferreira --- Centre for Aquatic Research, Department of Zoology, South Africa V. Wepener --- Centre for Aquatic Research, Department of Zoology, South Africa J. H. J. van Vuren --- Centre for Aquatic Research, Department of Zoology, South AfricaPans are isolated, shallow depressions that are endorheic in nature. Because of the natural hydrological functioning of pans, these systems are usually restricted to arid regions and complete desiccation occurs seasonally. In the eastern provinces of South Africa many pans... -
Zooplankton and diatoms of temporary and permanent freshwater pans in the Mpumalanga Highveld region, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Luisa Riato --- Department of Paraclinical Sciences, South Africa Carin Van Ginkel --- Cripsis Environment, South Africa Jonathan C. Taylor --- School of Biological Sciences, North-West University, South AfricaThis paper provides a description of the zooplankton and epiphytic diatom communities of permanent and temporary freshwater pans in the Mpumalanga Highveld region of South Africa. Few studies have investigated the biota of pans in this area, which is seriously... -
Blue Petrels Halobaena caerulea discovered breeding on Gough Island
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Peter G Ryan --- Percy FitzPatrick Institute of African Ornithology, DST–NRF Centre of Excellence, South Africa Ben J Dilley --- Percy FitzPatrick Institute of African Ornithology, DST–NRF Centre of Excellence, South Africa Christopher Jones --- Percy FitzPatrick Institute of African Ornithology, DST–NRF Centre of Excellence, South Africa Alexander L Bond --- RSPB Centre for Conservation Science, UKThe Blue Petrel Halobaena caerulea breeds at five subantarctic island groups and at islands off southern Chile in a narrow latitudinal band from 47° to 56° S on either side of the Antarctic Polar Front. We found a colony on... -
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 AfricaAquatic 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... -
Micro-scale heterogeneity of spiders (Arachnida:Araneae) in the Soutpansberg, South Africa: a comparative survey and inventory in representative habitats
Item type: Journal Article • Journal: African Zoology • Authors: S.H. Foord --- Department of Biological Sciences, South Africa M.M. Mafadza --- Department of Biological Sciences, South Africa A.S. Dippenaar-Schoeman --- Biosystematics Division, University of Pretoria, South Africa B.J. Van Rensburg --- Centre for Invasion Biology and Department of Zoology and Entomology, South AfricaCoarse-scale studies that focus on species distributions and richness neglect heterogeneity that may be present at finer scales. Studies of arthropod assemblage structure at fine (1 × 1 km) scales are rare, but important, because these are the spatial levels... -
IPO market cycles and expansion curse: Evidence from Chinese IPO market
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Yonghong Jin --- Department of Finance, School of Business, China Jianbang Guo --- Department of Finance, School of Business, China Xiaozhou Zhou --- Department of Finance, School of Business, China Sai-Ping Li --- Institute of Physics, Academia Sinica, TaiwanThere are two theories on the relationship between primary and secondary markets for securities. The first states that the expansion of IPO financing leads to a decline in stock prices, i.e. an expansion curse effect. The other states that the... -
Indirect methods of tree biomass estimation and their uncertainties
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Marco A Njana --- Tanzania Forest Services Agency, TanzaniaTree aboveground biomass (AGB) may be determined using direct (weighing or biomass models) and indirect (involving the use of a form factor [FF]) or volume models, basic density [BD] and biomass expansion factor [BEF]) methods. Focusing on three dominant mangrove... -
A new approach for the mix design of (patch) repair mortars
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Inès L. Tchetgnia Ngassam --- Department of Civil Engineering, South Africa Philemon Arito --- Department of Civil Engineering, South Africa Hans Beushausen --- Department of Civil Engineering, South AfricaThe failure of most repairs in concrete structures is mainly manifested in the form of cracking and/or debonding of the repair layer. These two repair mechanisms could lead to the continuous corrosion of reinforcing steel in concrete. Cracking and debonding... -
Influences of ecology and climate on the distribution of restricted, rupicolous reptiles in a biodiverse hotspot
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: MA Petford --- , , South Africa R van Huyssteen --- , , South Africa GJ Alexander --- , , South AfricaUnderstanding the role of climatic and ecological factors in limiting species to their distributions is becoming ever more important in a world where anthropogenic activities are increasingly threatening species persistence. Species with restricted distributions are often poorly known even though... -
Call repertoire of Ptychadena uzungwensis (Anura: Ptychadenidae) to complement molecular and morphological identification of the species from the Soutpansberg, South Africa.
Item type: Journal Article • Journal: Treading a Delicate Tightrope: A principal balancing between education and political change during turbulent times • Authors: Ferdi De Lange --- , South Africa Edward C Netherlands --- , South Africa Louis H Du Preez --- , South AfricaThe identity of adults and tadpoles of Ptychadena uzungwensis from the Soutpansberg range in northern South Africa was confirmed using a combination of morphological characters and molecular analysis. Detailed vocalisation analysis was made and used to complement existing species identification... -
Componentwise localization of solutions to systems of operator inclusions via Harnack type inequalities
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Radu Precup --- Institute of Advanced Studies in Science and Technology, Babeş -Bolyai University & Tiberiu Popoviciu Institute of Numerical Analysis, Romania Jorge Rodríguez-López --- CITMAga, Universidade de Santiago de Compostela, SpainWe establish compression-expansion type fixed point theorems for systems of operator inclusions with decomposable multivalued maps. The approach is vectorial allowing to localize individually the components of solutions and to obtain multiple solutions with multiplicity not necessarily concerned with all... -
Asymptotic properties for compressions of two-isometries
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Laurian Suciu --- “Lucian Blaga” University of Sibiu, RomaniaThe bounded linear operators T on a Hilbert space which have 2-isometric liftings S on are investigated in this paper. We refer to the structure of those operators in the case of general liftings, as well as for a more... -
Equidivisibility and profinite coproduct
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Jorge Almeida --- Universidade do Porto, Portugal Alfredo Costa --- University of Coimbra, PortugalThe 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... -
Supported approach spaces
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: E. Colebunders --- Vrije Universiteit Brussel, België R. Lowen --- Universiteit Antwerpen, BelgiëIn this paper we work in the category of approach spaces with contractions [14], the objects of which are sets endowed with a numerical distance between sets and points. Approach spaces are to be considered a simultaneous generalization of both... -
The monoidal nature of the Feistel-Toffoli construction
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Hans-E. Porst --- Stellenbosch University, South AfricaThe Feistel-Toffoli construction of a bijective Boolean function out of an arbitrary one, a fundamental tool in reversible computing and in cryptography, has recently been analyzed (see [12]) to be a special instance of the construction of a monoid homomorphism... -
First record of a large breeding colony of the Lesser Black-backed Gull Larus fuscus in mainland Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Mohamed Radi --- , Morocco El-Mustapha Laghzaoui --- Cadi Ayyad University, Morocco Aouissa Salek --- , Morocco Rhimou El Hamoumi --- Hassan II University of Casablanca, Morocco Mohamed Dakki --- , Morocco Abdeljebbar Qninba --- Scientific Institute, Mohamed V University, Morocco El Hassan El Mouden --- Cadi Ayyad University, Morocco Mohamed Aourir --- Ibn Zohr University, MoroccoA breeding colony of the Lesser Black-backed Gull Larus fuscus was discovered at the Khenifiss lagoon on the Atlantic coast of southern Morocco. In June 2022, 222 nests were counted and, in 2023, 62 nests were present. Nests were built... -
Best approximation theorems via relatively u-continuous and Jaggi nonexpansive mappings
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: M. Gabeleh --- Ayatollah Boroujerdi University, Iran R. Gholipour --- Yazd University, Iran H. Mazaheri --- Yazd University, Iran S.P. Moshokoa --- Tshwane University of Technology, South AfricaIn this paper, we introduced a new type of cyclic (noncyclic) mappings, called Jaggi relatively nonexpansive mappings and use to investigate the existence of best proximity points (pairs) in the framework of reflexive (strictly convex) Banach spaces by using a... -
The experiences of oppression among transgender and gender expansive young people in Australia: An interpretative phenomenological study
Item type: Journal Article • Journal: Journal of Child & Adolescent Mental Health • Authors: Daniel Abela --- Monash University, Australia Lefteris Patlamazoglou --- Monash University, Australia Sophie Lea --- Monash University, AustraliaBackground: Transgender and gender expansive (TGE) people experience poorer mental health outcomes compared to their cisgender counterparts. There is limited research on understanding the experiences of TGE school-aged young people from an Australian perspective. Since each country and state has... -
Approximation and Compactness
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: E. Colebunders --- Vrije Universiteit Brussel, België R. Lowen --- Universiteit Antwerpen, BelgiëIn approach theory convergence is described by means of limit and adherence operators acting on filters or ultrafilters. The value of the limit resp. adherence operator on an (ultra)filter in a point x is interpreted as the distance that the...