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Recovery of Ocotea bullata (Lauraceae) after Fire Damage
Item type: Journal Article • Journal: South African Forestry Journal • Authors: W.A. Lübbe --- Saasveld Forestry Research Centre,Fire damage to Ocotea bullata (Lauraceae) may result in crown death but survival and eventual recovery is possible by means of shoot formation. Survival is due to the above-average thickness of the bark of O. bullata and possibly the isolating... -
Decline and Mortality of Ocotea bullata Trees in the Southern Cape Forests
Item type: Journal Article • Journal: South African Forestry Journal • Authors: W.A. Lübbe --- Saasveld Forestry Research Centre, C.J. Geldenhuys --- Saasveld Forestry Research Centre,Dying trees of Ocotea bullata (Lauraceae) occurred in small groups in certain areas in the medium-moist forests of the southern Cape. Crown health declined significantly (P > 0,01) in the dying groups, but this was not the general trend for... -
Pruning Studies in Pinus radiata
Item type: Journal Article • Journal: South African Forestry Journal • Authors: W. H.F. Hinze --- Forestry Branch, Department of Environment Affairs, A. van Laar --- Faculty of Forestry,Pruning trials were established in stands of Pinus radiata in three plantations in different climatic regions. The objective of the experiments was to assess the effect of a first, second, third and fourth pruning on mortality, on diameter, height and... -
Epimorphisms of metric frames
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Bernhard Banaschewski Aleš PultrThis paper deals with several aspects of epimorphisms in the category MFrm of metric frames and contractive homomorphisms. In particular, it is shown that i. the epicomplete metric frames are uniquely determined by the power-set lattices of sets,... -
First record of an intraleucocytic haemogregarine (Adeleorina: Haemogregarinidae) from South African tortoises of the species Stigmochelys pardalis (Cryptodira: Testudinidae)
Item type: Journal Article • Journal: African Zoology • Authors: Courtney A. Cook --- Department of Zoology, South Africa Nico J. Smit --- Water Research Group (Ecology), Unit for Environmental Sciences and Management, North-West University, South Africa Angela J. Davies --- Water Research Group (Ecology), Unit for Environmental Sciences and Management, North-West University, South AfricaTo date, four intraerythrocytic apicomplexans, namely the haemogregarines Haemogregarina fitzsimonsi and Haemogregarina parvula, and the haemoproteids Haemoproteus testudinalis and Haemoproteus natalensis, have been described from South African land tortoises. Recently, an intraleucocytic haemogregarine was observed in one species of tortoise,... -
First Hemolivia from southern Africa: reassigning chelonian Haemogregarina parvula Dias, 1953 (Adeleorina: Haemogregarinidae) to Hemolivia (Adeleorina: Karyolysidae)
Item type: Journal Article • Journal: African Zoology • Authors: Courtney A Cook --- Unit for Environmental Sciences and Management, North-West University, South Africa Edward C Netherlands --- Unit for Environmental Sciences and Management, North-West University, South Africa Nico J Smit --- Unit for Environmental Sciences and Management, North-West University, South AfricaTo date, only a single species of Hemolivia, Hemolivia mauritanica (Sergent & Sergent, 1904), has been described from African terrestrial tortoises. Although various haemogregarines have been described from southern African terrapins and tortoises, including species from the genus Haemogregarina and... -
Rotaviruses and emerging picornaviruses as aetiological agents of acute gastroenteritis
Item type: Journal Article • Journal: Southern African Journal of Epidemiology and Infection • Authors: Caroline Knox --- Department of Biochemistry, Garry Luke --- Centre for Biomolecular Sciences, School of Biology, Biomolecular Sciences Building, University of St Andrews, United Kingdom John Dewar --- Department of Life and Consumer Sciences, Pablo de Felipe --- Agencia Española de Medicamentosy Productos Sanitarios (AEMPS) Calle Campezo 1, Edifcio 8, Spain Brittany Williams --- Department of Biochemistry,It is estimated that up to 40% of acute gastroenteritis cases are undiagnosed. Rotavirus is a primary aetiological agent, so the introduction of vaccines into the national immunisation programmes of many countries, including South Africa, has shown promise in reducing... -
Design basics of a small hydro turbine plant for capacity building in sub-Saharan Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Williams S. Ebhota --- Department of Mechanical Engineering, South Africa Freddie Inambao --- Department of Mechanical Engineering, South AfricaThis paper presents a simplified design considerations for a propeller hydro-turbine, including tabulated relevant mathematical expressions of operating parameters. In the design calculation, a 2.5 m head and 0.183 m3/s flow rate were used as river data for power of... -
Trait variations in 28-year-old teak (Tectona grandis) provenance field trials in Ghana, West Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Stephen Adu-Bredu --- CSIR-Forestry Research Institute of Ghana, Ghana Daniel A Ofori --- CSIR-Forestry Research Institute of Ghana, Ghana Anders Ræbild --- Department of Geosciences and Natural Resource Management, Faculty of Science, Denmark Jon K Hansen --- Department of Geosciences and Natural Resource Management, Faculty of Science, Denmark Appolinaire Koffi --- Société de Développement defs Forêts (SODEFOR), Côte d’Ivoire Philipp Vigneron --- CIRAD, Forest Department, Research Unit 39, Diversity and Breeding of Forest Tree Species, France Erik D Kjær --- Department of Geosciences and Natural Resource Management, Faculty of Science, DenmarkStem straightness, axis persistence, presence/absence of protuberant buds and epicormics, diameter and height have profound influence on timber quality and volume of teak (Tectona grandis). Provenance trials of teak were established in the 1970s in Ghana, as part of the... -
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... -
Describing sexual dimorphism and fine scale spatial distributions in the Drab Thick-tail Scorpion, Parabuthus planicauda
Item type: Journal Article • Journal: African Zoology • Authors: Jacobus H Visser --- , South Africa Sjirk Geerts --- , South AfricaSouthern Africa contains a diverse and endemic scorpion fauna, but with biological aspects remaining largely unexplored for this group. In order to gain biological insights into an understudied scorpion species, the current study investigates fine-scale spatial distributions and sexual dimorphism... -
The impact of cell selection on the energy efficiency of heterogeneous networks
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Michael Oyakhilome --- , Finland Kazeem B. Adedeji --- , South AfricaThe growth of the information, communication and telecommunication (ICT) industry is on the ascendancy. The proliferation of mobile devices and other web-based applications has compelled ICT industries to deploy more resource towards capacity expansion and improved quality of service. This... -
A new species of Trachylepis Fitzinger, 1843 (Squamata: Scincidae) from central African forests
Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: Laurent Chirio --- Muséum national d'Histoire naturelle, France Ivan Ineich --- Muséum national d'Histoire naturelle, France Andreas Schmitz --- Muséum d'Histoire naturelle de la Ville de Genève (MHNG), Switzerland Matthew LeBreton --- CRESAR, CameroonIntensive collection and field observations in the Central African Republic revealed a previously undescribed skink species of the genus Trachylepis. Morphologically this species seems to be related to Trachylepis boulengeri and/or T. polytropis, but genetic analysis showed that this is... -
Effects of thinning on growth performance of teak (Tectona grandis) plantations in Tain II Forest Reserve, Ghana
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Bertrand Festus Nero --- Kwame Nkrumah University of Science and Technology, Ghana Maxwell Asuenabisa --- Kwame Nkrumah University of Science and Technology, GhanaAlthough recent interest in commercial teak plantation establishment has soared, knowledge of intensive silvicultural management of residual stands is limited in most parts of West Africa. This study evaluated the effects of thinning regimes on the growth responses and pruning...