ENGLISH: This thesis is a study of the microstructure of hair of southern African mammals, in particular of the Carnivora. It serves to fill a gap in knowledge of hair studies from this region, and points to the use of these studies in various fields. A major portion of the work is a hair atlas of southern African Carnivora, in which micrographs and coloured plates of hairs are presented with locality data and a descriptive text for each species. Although the findings of the atlas do not lend themselves to the formation of dichotomous key, it serves as a reference system and has proved useful in the identification of hairs from selected study areas where species distribution is defined. This is intended to form part of a comprehensive atlas which will include examples of all southern African mammal species. Techniques for studying hair structure are discussed and the micrographs of both thin and thick cross-sections are included to demonstrate the results of different methods used. The taxonomic importance of hair identification is well known and examples of this are discussed , mainly in regard to the smaller mammals, such as the Muridae. The extent to which hair morphology can be used as a taxonomic criterion varies with various groups however, but more often than not, by using a combination of parameters it is possible to differentiate many species. The identification of unknown hair samples has been discussed, with special reference to the highly practical field of epidemiology. Examples of both laboratory investigations, as well as field surveillance, in which hair identification is used have been cited as an important aspect of hair studies. The extent to which hair is related to ecology forms a broad field of study, and for this reason those situations where ecologically selective pressures are more clearly defined have been chosen for particular mention. Thus the aquatic habitat and the desert environment are discussed with reference to the hair types such as guard hairs, underfur, and the microstructure of hair as well as its mechanical and surface properties. Thermoregulation is referred to and arising out of this aspect a hypothesis is presented in which the part played by the medulla in the absorption of longwave infrared radiation is discussed.AFRIKAANS : Hierdie proefskrif handel oor 'n studie van die mikrostruktuur van die hare van soogdiere van suidelike Afrika en in besonder die van karnivore. Dit vul 'n leemte aan in ons kennis ocr haarstudies in hierdie gebied en dui op die gebruike van hierdie studies op verskillende terreine. 'n Groot deel van die werkstuk word beslaan deur 'n haaratlas van die karnivore van suidelike Afrika waarin mikrofotos en kleurplate van hare tesame met lokaliteitsdata en beskrywende teks vir elke spesie aangebied word. Alhoewel die bevindinge aangebied in die atlas hulle nie leen tot die opstelling van 'n tweedelige identifikasiesleutel nie, dien die atlas wel as 'n nuttige hulpmiddel vir die identifikasie van hare in sekere areas waar spesieverspreiding bekend is. Hierdie resultate sal uiteindelik deel uitmaak van 'n omvattende atlas oor die hare van soogdierspesies in suidelike Afrika . Tegnieke vir die studie van haarstruktuur word bespreek en mikrofotos van beide dun en dik dwarsnitte word ingesluit om die resultate wat met die verskillende metodes verkry is, te demonstreer. Die taksonomiese belang van haaridentifikasie is welbekend en voorbeelde hiervan word bespreek, veral wat die kleiner soogdier betref soos die Muridae. Die mate waartoe haarmorfologie as taksonomiese maatstaf gebruik kan word, varieer egter in die verskillende groepe maar gewoonlik, deur die gebruik van verskillende parameters, is dit moontlik om tussen baie spesies te onderskei. Identifikasie van haarmonsters van onbekende oorsprong word bespreek met spesiale verwysing na die hoogs praktiese veld van epidemiologie. Voorbeelde van laboratoriumondersoeke sowel as veldopnames waar haaridentifikasie gebruik is, word aangehaal as ‘n belangrike faset van haarstudies. Die verband tussen hare en ekologie behels ‘n breë studieveld en om die rede is toestande waar ekologiese selektiewe druk meer duidelik gedefineer is spesiaal vermeld. Die akwatiese habitat en woestynomgewing word dus bespreek met verwysing na haartipes soos beskermhare, onderpels en die mikrostruktuur van hare sowel as die meganiese en oppervlakte-eienskappe van hare. Daar word na termoregulering verwys en voortspruitend daaruit word 'n hipotese voorgestel waarin die bydrae van die medulla in die absorpsie van lang infra-rooi-radiasie bespreek word. Copyright / Thesis (DSc)--University of Pretoria, 2011. / Zoology and Entomology / unrestricted

Tropical cyclones claim a huge number of lives and cause substantial damage to property and crops in many regions each year. Southern Africa is no exception. This makes the process of forecasting tropical cyclones of great importance to the region’s economy and to public safety. Skillful seasonal forecasts of tropical cyclone activity could be used to warn the communities affected by tropical cyclones of the likely occurrence of such systems ahead of the cyclone season. This could result in reduced damage and fatalities associated with such systems. Both statistical and dynamical techniques have been employed in an attempt to predict tropical cyclone activity on a seasonal time scale over a number of ocean basins. The skills of such techniques vary from one technique to another and from one basin to another. This study investigates the predictability of tropical cyclone activity on a seasonal time scale over the southwestern Indian Ocean (SWIO) by nesting a regional climate model (RCM), the RegCM3 within a coarse-resolution atmospheric general circulation model (AGCM), the ECHAM4.5. The national meteorological centres of most southern African countries do not have the required dedicated computational resources to run the high-resolution GCMs that are suitable to predict these systems operationally. However, these systems can be very devastating on the southern African region and need to be predicted on various time scales, including the seasonal time scale. Therefore, it is instructive that research be done to better our understanding of these systems and their predictability using physical models. This study examines the simulations of the genesis locations and the number of tropical cyclones produced in RCM integrations nested within an AGCM forced by observed sea-surface temperatures (SSTs). The season of interest is the mid-summer period of December to February. Four members of the AGCM generated at the International Research Institute for Climate and Society (IRI) are used to force the RCM. Four-month integrations over a 10-year period (1991/92-2000/01) are performed. An objective procedure for detecting model-generated tropical cyclones is applied to this ensemble. Some characteristics of the simulated cyclones are compared with the observations. In addition, some statistical techniques are employed to evaluate the capability of the RCM to reproduce some aspects of the observed tropical cyclones during the aforementioned period. The results show that there is a good agreement between two of the simulated and observed environmental variables that influence tropical cyclone formation, viz. vertical wind shear and relative vorticity. In particular, the simulated and observed vertical wind shear show a similar pattern in most parts of the model domain. With regards to the relative vorticity, the highest agreement is found in the Mozambique Channel and in the region east of Madagascar. In addition, there is an appreciable agreement between the simulated and observed tropical cyclone characteristics such as tropical cyclone genesis locations and frequency. The model also simulated the interannual variability in the tropical cyclone frequency skillfully. AFRIKAANS : Tropiese siklone is verantwoordelik vir ‘n goot aantal sterftes en veroorsaak beduidende skade aan eindom asook oeste oor etlike areas elke jaar. Suidelike Afrika is nie ‘n uitsondering nie. Hierdie verliese maak die voorspelling van tropiese siklone van groot belang vir die gebied se ekonomie asook vir publieke veiligheid. Vaardige seisoenale voorspelling van tropiese sikloon aktiwiteit kan gebruik word om gemeenskappe wat onderhewig is aan die invloed van tropiese siklone te waarsku oor die kans vir sulke sisteme om voor te kom voordat die tropiese sikloon seisoen ‘n aanvang neem. Vroegtydige waarskuwings kan tot gevolg hê dat daar minder verwant skade en laer sterftes is. Beide statistiese en dinamiese tegnieke is al in die verlede gebruik om tropiese sikloon aktiwiteit oor verskeie oseaankomme op ‘n seisoenale tydskaal te probeer voorspel. Die vaardigheid van hierdie tegnieke hang af van die tipe tegniek wat gebruik word asook watter oseaankom beskou word. Hierdie studie ondersoek die voorspelbaarheid van tropies sikloon aktiwiteit op ‘n seisoenale tydskaal oor die suid-westelike Indiese Oseaan deur gebruik te maak van ‘n streeksmodel, die RegCM3, genes in ‘n growwe-resolusie algemene sirkulasie model van die atmosfeer, die ECHAM4.5. Die nasionale weerdienste van die meerderheid Suider-Afrikaanse lande beskik nie oor die nodige rekenaars om geskikte hoë-resolusie algemene sirkulasie modelle te loop om sodanige sisteme mee operasioneel te voorspel nie. Desnieteenstaande kan hierdie tropiese sisteme verwoestend wees en daarom behoort hulle voorspel te word op verskeie tydskale, insluitende seisoenale tydskale. Dit sal dus insiggewend wees om navorsing te doen om sodoende ons begrip oor hierdie sisteme en hul voorspelbaarheid te verbeter deur gebruik te maak van fisiese modelle. Hierdie studie gaan ondersoek instel oor die simulasie van tropiese siklone oor hul ontwikkelingsgebiede en die aantal tropiese siklone wat ‘n streeksmodel, genes in ‘n algemen sirkulasie model van die atmosfeer wat geforseer word deur waargeneemde see-oppervlak temperature, kan produseer. Die seisoen van belang is die mid-somer periode van Desember tot Februarie. Vier ensemble lede afkomstig vanaf die algemene sirkulasie model wat geloop is by die International Research Institute for Climate and Society word gebruik om die streeksmodel mee te forseer. Model integrasies word oor ‘n 4-maand periode gedoen en vir ‘n 10-jaar tydperk (1991/92-2000/01). ‘n Objektiewe vorteks opsporingsprosedure word dan toegepas op die 4-lid ensemble om model-geskepte tropiese siklone te identifiseer. Sommige van die karakteristieke van die gesimuleerde siklone word dan vergelyk met die waargeneemde tropiese stelsels. Hiermee saam word statisiese tegnieke ingespan vir die genoemde tydperk om die vermoë van die streeksmodel te ondersoek om sekere aspekte van waargeneemde storms te herproduseer. Die resultate wys dat daar ‘n goeie ooreenkoms is tussen twee van die gesimuleerde en waargeneemde omgewingsveranderlikes wat tropiese sikloon ontwikkeling beinvloed, nl, vertikale windskuiwing en relatiewe vortisiteit. In besonder het die gesimuleerde en waargeneemde vertikale windskuiwing ooreenstemmende patrone gelewer oor die grootste gedeelte van die streeks model-area. Wat relatiewe vortisiteit betref, is die beste ooreenkoms oor die Mosambiek kanaal en in die gebied oos van Madagaskar gevind. Verder is daar ‘n sterk ooreenkoms tussen die gesimuleerde en waargeneemde tropiese sikloon karakteristieke soos by die tropiese siklone se ontwikkelingsgebiede asook hul frekwensie. Die model he took daarin geslaag om die inter-jaarlikse veranderlikheid van tropiese sikloon frekwensie suksesvol te simuleer. / Dissertation (MSc)--University of Pretoria, 2010. / Geography, Geoinformatics and Meteorology / MSc / Unrestricted

The high value of good health in Africa and the serious threat to life posed by diseases that plague the African continent including South Africa, are highlighted in this thesis. The question whether the church in South Africa as a stakeholder in human development in Africa, contributes meaningfully to the continental and national vision of "a better life for all" or "good health for all" is posed and an attempt made to answer it. Operating from the Western world-view, the Hervormde Kerk in Suidelike Afrika (HKSA) is found not to be contributing meaningfully to the realisation of the African vision of "good health for all". Resistance to cure and healing by means of Western medicine and pastoral care and counselling as well as a lack of spiritual and numerical growth in the HKSA are identified as consequences of the imposition of exclusively Western Christian theological formulations on the African church. The assumption underlying this thesis is that ministry to the sick in the African mainline churches should recognise the role played by supernatural forces in the belief systems of Africans regarding health and illness. This assumption is based on the fact that theological formulations are socially influenced and constructed. Following Zerfass' methodological model, this research examines the principles underlying the ministry to the sick in the HKSA and the Nederduitsch Hervormde Kerk van Afrika (NHKA); highlights the core African beliefs with regard to the health and illness discourse and practice; points out the shortcomings of the current ministry to the sick in the HKSA. The findings of the investigation into the theological tradition and the results of the exploration of the literature on the African context are brought into the critical dialogue. On the strength of findings of the critical dialogue between the church's traditional theological theory and the results of the exploration of the literature on the African context, the church's healing ministry is recommended as a necessary part of the church's official task in a black South African context. / Practical Theology / D.Th. (Practical Theology)

The high value of good health in Africa and the serious threat to life posed by diseases that plague the African continent including South Africa, are highlighted in this thesis. The question whether the church in South Africa as a stakeholder in human development in Africa, contributes meaningfully to the continental and national vision of "a better life for all" or "good health for all" is posed and an attempt made to answer it. Operating from the Western world-view, the Hervormde Kerk in Suidelike Afrika (HKSA) is found not to be contributing meaningfully to the realisation of the African vision of "good health for all". Resistance to cure and healing by means of Western medicine and pastoral care and counselling as well as a lack of spiritual and numerical growth in the HKSA are identified as consequences of the imposition of exclusively Western Christian theological formulations on the African church. The assumption underlying this thesis is that ministry to the sick in the African mainline churches should recognise the role played by supernatural forces in the belief systems of Africans regarding health and illness. This assumption is based on the fact that theological formulations are socially influenced and constructed. Following Zerfass' methodological model, this research examines the principles underlying the ministry to the sick in the HKSA and the Nederduitsch Hervormde Kerk van Afrika (NHKA); highlights the core African beliefs with regard to the health and illness discourse and practice; points out the shortcomings of the current ministry to the sick in the HKSA. The findings of the investigation into the theological tradition and the results of the exploration of the literature on the African context are brought into the critical dialogue. On the strength of findings of the critical dialogue between the church's traditional theological theory and the results of the exploration of the literature on the African context, the church's healing ministry is recommended as a necessary part of the church's official task in a black South African context. / Philosophy, Practical and Systematic Theology / D.Th. (Practical Theology)