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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

The integration of traditional and modern architectural form : a proposed socially active centre for skills development in Southern Africa.

Phiri, Chisomo Kelvin. January 2011 (has links)
This research is a study of traditional and modern architecture and how the aforementioned systems can and should integrate into Afro-centric architecture. The emphasis was on the architecture one tends to enjoy as an African, explored and juxtaposed against the thoughts and theoretical frameworks of culture sensitive architects worldwide. In this dissertation, the aspects of integrative theory were explored. Primary theories dealing with sustainability, New African Architecture, Indigenous Knowledge and Semiology were assessed as well. The differences between traditional Africa and modern adaptations, both positive and negative, were the limit of the research. In the dissertation certain key questions are posed to drive the inquiry of the document. The hypothesis is the conjecture that a connection between modernized architecture and traditional semiotics exists and can be cultivated to flourish, developing African architecture at all levels. This conjecture acts as a base for primary and secondary research. There are accounts listed in this dissertation of richly meaningful and sensitive traditional architecture that show a connection between American, Asian, African and European primitive building styles. These accounts show practices that have lasted near as long as the society that invented them. The gathered information shows that these examples have undergone little change over the years. The dissertation argues that the value these instances of traditional architectural meaning lessened over the years due to a shift in cultural paradigms. Further chapters in the study address cosmology, African attitudes to space, the reinvention of old materials and the manifestation and celebration of new tectonic relationships. Lessons collected on the above listed issues were related against findings from verbal interviews, written questionnaires and observations at the site of case studies. It is the researcher’s desire to explore the potential for an integrative developmental institute. To this end, an assessment has been done both in the form of precedent embedded in the text and Case Studies of relevant buildings that relate to the subject matter of the dissertation. The analysis of these assessments shows a manifested potential for the integration of traditional designs with modern building. / Thesis (M.Arch.)-University of KwaZulu-Natal, Durban, 2011.
112

Aspects of nocturnal physiology and behaviour in malachite sunbirds (Nectarina famosa).

Wellmann, Andrea Erika. January 2007 (has links)
Although sleep forms an important part of an animal’s life, there is a paucity of knowledge about sleep behaviour. The function of sleep in birds is poorly understood, even though birds spend a large part of their lives sleeping. Sleep behaviour in passerine birds has not been looked at as extensively as that of non-passerine birds. I looked at the sleep behaviour of three relatively common passerine birds occurring in southern Africa, namely the Malachite Sunbird (Nectarinia famosa), the Cape White-eye (Zosterops pallidus) and the Fan-tailed Widowbird (Euplectes axillaris). By using an infra-red sensitive camera I described basic sleep behaviours at various ambient temperatures, of all three species, such as sleep position and eye closure, and also investigated the incidence of unihemispheric sleep. Individuals of all three species spent most of the night asleep and kept on waking up intermittently throughout the night, with no significant differences between temperatures. Cape White-eyes and Malachite Sunbirds showed an increase in back sleep and a decrease in front sleep at 5oC. Little evidence of unihemispheric sleep was found, suggesting that it is more likely to occur in non-passerines, especially ground dwelling birds. Diurnal birds generally sleep during the hours of darkness. Most male southern African sunbirds have pectoral tufts, although the function of these is not always understood. In male Malachite Sunbirds it has recently been found that they display their pectoral tufts almost continuously throughout the night, whilst asleep. I explored the possible function of this behaviour and suggest that these tufts might be a deterrent to predators, as they look like ‘eyes’ in the dark. A review of the use and occurrence of pectoral tufts in southern African sunbird species is also presented. Blood glucose concentrations of most birds are much higher than those found in mammals and it is still not known how they evade the complications of such high levels. I investigated the change in blood glucose concentrations of Malachite Sunbirds at two different ambient temperatures and at different times of the night and day and explored the possibility that gluconeogenesis might be used by birds to ‘warm up’ during arousal of torpor in the early morning, before daylight. Generally blood glucose levels were fairly high, between 13.6 and 21.4 mmol/L, which was expected. Blood glucose levels were higher at 5oC than at 25oC and generally lower in the early hours of the morning. Therefore I reject the assumption that Malachite Sunbirds use gluconeogenesis as an additional form of heat generation during torpor. It is thought that the difference in the levels of blood glucose might be a function of the cold temperature and the consumption of their nectarivorous diet. This research clearly highlights the need for further studies to be undertaken in the sleeping behaviours and patterns of birds, especially in southern African species. It also shows that more studies need to be done on the use of pectoral tufts in sunbird species and furthermore it is suggested that more research is needed to elucidate the mechanism by which Malachite Sunbirds are able to rapidly ‘warm up’ during arousal, when in torpor. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.
113

Ontwikkeling van volhoubare toerisme as oplossing vir landelike armoede in Suider-Afrika

Albertyn, Rowan 03 1900 (has links)
Thesis (MS en S)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: More than half of the population of Southern Africa live in rural areas and lead a marginal existence. They are dependant on natural resources that are to their disposal for their survival. The resources that they use are renewable but are currently exploited faster that it can be replaced. The pressure that the rural populations are placing on nature cannot be sustained. The concept of "sustainable development" came into being in 1987. The principle of this new concept was to permit development as to meet the needs of the present without compromising the ability of future generations to meet their own needs. Sustainable development proposes a lifestyle that preserve nature as well as social and cultural characteristics of a community. The tourism industry of Southern Africa has great potential and is still growing. Ecotourism, the idea of nature based tourism that will benefit both the socio-economic circumstances of the community and conservation, have increased in the past ten years. If ecotourism is managed correctly, it can be the answer to poverty in many rural communities and at the same time conserving nature. There are organisations that concentrate on sustainable rural development and that introduce communities to the potentials and benefits of the tourism industry. There are already communities that adopted this new paradigm with great success. The aim of this study is to make people conscious to the problem of rural poverty and the impacts it has had on the environment already. Secondly the study also presents a solution to rural poverty by the development of tourism in rural communities. / AFRIKAANSE OPSOMMING: Meer as die helfte van Suider-Afrika se bevolking leef in landelike gebiede en voer 'n marginale bestaan. Hulle is aangewese op die natuurlike hulpbronne wat tot hulle beskikking is vir hulle voortbestaan. Die hulpbronne is hernubaar maar word tans vinniger verbruik as wat dit vervang word. Die druk wat die arm landelike bevolking op die natuur plaas kan nie volgehou word nie. In 1987 het die begrip "volhoubare ontwikkeling" die lig gesien. Die beginsel van die konsep is om ontwikkeling te laat geskied sodat daar aan die behoeftes van die hede voldoen word sonder om die behoeftes van die toekomstige geslagte te belemmer. Volhoubare ontwikkeling stel 'n lewenswyse voor wat nie net die natuur preserveer nie, maar ook die sosiale en kulturele sy van 'n gemeenskap. Die toerismebedryf in Suider-Afrika het baie potensiaal, en is steeds besig om te groei. Ekotoerisme, die idee van natuur-gebasseerde toerisme wat kan bydra tot die verbetering van sosio-ekonomiese toestande en bewaring van die omgewing, het toegeneem in die laaste tien jaar. Indien ekotoerisme reg bestuur word, kan dit vir 'n groot deel van die landelike bevolking 'n uitkoms tot armoede bied terwyl die natuur bewaar word. Daar is organisasies wat konsentreer op volhoubare landelike ontwikkeling en wat die gemeenskap bekend stel aan die voordele en potensiaal van die toerismebedryf. Daar het reeds verskeie gemeenskappe betrokke geraak in die toerismebedryf met groot welsae. Hierdie studie is 'n oorsig van bestaande literatuur oor die rol van toerisme en spesifiek, ekotoerisme in volhoubare ontwikkeling in landelike dele.
114

Networking: enabling professional development and institutionalisation of environmental education courses in Southern Africa

Lupele, Justin Kalaba January 2007 (has links)
This study was aimed at understanding how networking can enable or constrain professional development and institutionalisation of environmental education courses in southern Africa in the context of the Course Development Network (CDN), a project of the Southern Africa Development Community Regional Environmental Education Programme (SADC REEP). The study involved 12 institutions (each institution was represented in the CDN by a staff member) in eight SADC member states. It was contextualized through a review of social, political, environmental and educational developments in southern Africa, with specific reference to regionalization processes, as the SADC REEF is constituted under this post-colonial political framework. Relational philosophy informed the research process and methodology. The philosophy underpinned three distinct, yet related theoretical perspectives namely: critical realism, which provided the ontological perspectives of the study; Actor Network Theory; and Community of Practice, which provided the epistemological perspectives. Data was generated during a 33-month period in southern Africa and 12 months in the United Kingdom (and on a one week visit to Italy). During a 12 month Split Site Commonwealth Scholarship award, tenable at Manchester Metropolitan University in the United Kingdom, I studied the Environment and School Initiative (ENSI) and the Sustainability Education for European Primary Schools (SEEPS), to examine whether the same mechanisms that made them successful would apply to the CDN in the context of southern Africa. While these two case studies provided useful insight into the relationship between networking, professional development and institutionalization of environmental education programmes, they were not the main focus of the research. Data analysis was mainly through inductive, abductive and retroductive modes of inference. Inductive data analysis was done by means of Nvivo – a computer software package used for qualitative data analysis. The software aided in revealing features and relationships in the data in more depth as it allowed flexibility in working with data. Abduction is the interpretation of a phenomenon by means of a conceptual framework. In this study, I used Actor Network Theory (ANT) (Latour & Woolgar, 1979; Callon, 1986) and Community of Practice (COP) (Lave, 1988; Lave & Wenger, 1991; Fullan, 2003) as analytical conceptual frameworks to probe networking and professional development respectively. Data on institutionalisation of environmental education courses was analysed by means of retroductive mode of inference, which is a thought operation that enables the understanding of social reality beyond what is empirically observable or experienced. This study reveals that there were a number of necessary (internal) and contingent (external) factors that enabled or constrained networking, professional development and institutionalisation of environmental education courses in the context of the CDN. The key factors included existing cultural capital, donor political economy, power relations, poverty related factors and social transformation trends. The study found that relational approaches and the use of three relational theoretical lenses provided a broader lens which enabled this study to identify different dynamics, greater ontological depth and understanding of the relational dynamics and relations at play in the CDN beyond the participants' experience and observable events. The study also contends that networking can provide a support structure for social transformation and change in environmental education.
115

Investigating linkages between human capital, social development and corruption : evidence from a 'SADC' cross-country empirical study using panel data

Tandia, Papa Malamine 06 1900 (has links)
Corruption remains one of the most enduring phenomenon across the world and notably in Sub Saharan Africa where its scope and depth still culminate generally at distressing levels to a greater or lesser extent across countries and regions. This study presents an empirical analysis of the causes and association types of corruption across SADC countries. Through quantitative methods of analysis, it delivers an assessment of the conditional effect of the human capital and social development along with their respective and combined impact on a corruption model using panel data and multivariate regression estimates across the fifteen SADC countries for the period 2005 - 2013. The research then identifies other covariates economic or institutional - and their functional dependence to the hypothesised triad nexus - that may predict the diversity of corruption level outcomes in the region.The hypotheses considered and tested suggest that both human capital (HC) and social development (SD) are key determinants of corruption outcome levels. We report consistently strong R squared (R2) and high magnitude coefficients for the two variables under several estimation models and for various other control economic and governance variables. For robustness testing, alternate measures of corruption are also used. The results mostly but not entirely support the initial findings. The inclusion of the institutional variables does not confirm for SADC countries the largely found negative association of corruption with democracy and press freedom. Hence young and developing democracies across the region may not benefit from lower levels of corruption in the short run as institutional frameworks in formation remain weak. Meanwhile this research did not allow to derive clear arguments in relation to true causality and effects’ directions. The results remain agnostic with regards to causation between corruption and the selected explanatory variables. In the end human capital and social development in particular were found to be strong and consistent predictors of corruption control and the associations remain robust and significant under numerous specifications. While omnipresent rhetoric has largely focused on the political dimensions of corruption this study provides a substantial evidence and a nuance contribution to knowledge and literature to the concept of corruption by introducing the interaction effects of human capital and social development which indicate that both explanatory variables are consistent predictors of corruption control levels. In the footsteps of Sen’s theory, it offers a new frame which grants an understanding of the phenomenon of corruption from a capability and human development approach as a new avenue for research. All of which has crucial policy implications for concerned governments. Indeed, efforts to stamp out corruption should be designed first to eliminate or mitigate the root - conditions of its incidence focusing on policies geared towards better education and higher living standards. Relying chiefly on oversight agencies and lending disproportionate attention to enforcement actions and regulatory frameworks would indeed prove to be a misplaced priority. Fundamentally this thesis argues a new scheme of intelligibility, a renewed “episteme” of corruption which refers to the order of human developmental structures underlying the production of corrupt practices. / Business Management / D.B.L.
116

Antimicrobial activity of Melianthus villosus

Lentsoane, Robert 23 May 2005 (has links)
Many South Africans continue to use traditional medicine in their daily lives as an alternative form of health care, also as part of their cultural heritage. Medicinal plants are proving to be an important source of novel drugs, and the knowledge provided by traditional healers is a useful tool in the search for antimicrobials. The antimicrobial activity of <M. villosus was investigated against ten bacteria and six fungi. The antibacterial assay showed that the root extract had the highest inhibition against the Gram-positive bacteria at the minimum inhibition concentration of o.1 mg/ml, as well as against the Gram-negative, E. coli, at the MIC of 1.0 mg/ml. Antifungal activity was witnessed against Cladosporium cladosporoide, C. cucumerinum&C sphaerosperum all at the minimum inhibitory concentration of 1.0 mg/ml. An attempt was made to isolate and identify the active antimicrobial compounds. A flavonol, quercetin was isolated and identified by means of UV spectral graphs, and TLC comparison of the plant extract and standard. However, a second isolated antibacterial compound could not be identified fully but it can be said that it is a triterpenoid. / Dissertation (MSc (Botany))--University of Pretoria, 2006. / Plant Science / unrestricted
117

The Southern African Development Community's attraction to foreign direct investment

Botha, Richard Kruger January 2008 (has links)
In order to assess the question as to whether the Southern African Development Community in principle attracts foreign direct investment, literature and data have been cited that compared the economic profiles and relative privatisation programs of member states of the Southern African Development Community with relative high inflows of foreign direct investment with the economic profiles and relative privatisation programs of member states with relative low inflows of foreign direct investment. Qualitative research has been conducted, and the author is of opinion that generally the member states with relative high foreign direct investment inflows had economic profiles and relative privatisation programs that encouraged foreign direct investment, and member states with relative low foreign direct investment inflows had economic profiles and relative privatisation programs that deterred foreign direct investment inflows. From the above the author has inferred that the Southern African Development Community in principle attracted foreign direct investment, but not to its full potential. The reason may be that although the member states’ economic profiles are favourable for foreign direct investment, their economic growths tend to fluctuate, and the future economic profiles are therefore unpredictable. With the above in mind this mini-treatise aims to address the question as to what steps the governments of the Southern African Development Community’s member states could follow in order to attract foreign direct investment. iii The author is of opinion that the member states should endeavour to maintain an annual average economic growth rate, and that the governments continue to engage into privatisation programs in order to encourage foreign direct investment.
118

An analysis of population structure using microsatellite DNA in twelve Southern African populations of the Mozambique tilapia, Oreochromis mossambicus (Peters)

Hall, Edward G. 12 1900 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: DNA micro satellite loci express extensive allelic variation making them convenient markers for research in many fields employing population genetic tools, including aquaculture and conservation genetics. Twelve Oreochromis mossambicus populations from wild, captive and introduced sources in Southern Africa were screened for genetic variation at ten CA repeat micro satellite loci. Three of the loci - UNHI04, UNHlll, and UNH123 - were sufficiently well resolved to screen extensively and were interpreted according to a model of Mendelian inheritance. Data was analyzed in terms of genetic structure and levels of genetic variation, the effect of management regime in captivity through successive generations on genetic diversity, and the nature of phylogenetic relationships present between populations. Exact tests, carried out using Monte Carlo type multiple resampling techniques, and F-Statistics were used to detect and quantify genetic structure among the twelve populations. The Exact test X2 (P < 0.001), a FST of 0.27 (P < 0.001), eST of 0.26, RsT of 0.28, and a <l>ST of 0.17 all indicated significant structuring among the populations. The evident genetic structuring endorsed the practice of maintaining the populations as separate genetic stocks, in separate tanks, in order to preserve unique genetic material for aquaculture strain development. Populations also exhibited some significant deviations from Hardy Weinberg equilibrium characterised by an overall reduced heterozygosity across the loci. In microsatellite studies, null alleles are often suggested as major contributors to heterozygote deficits. To test for null alleles, two controlled crosses of 0. mossambicus were made. The progeny from each cross were examined for expected parental allelic ratios at the UNHI04, UNHlll and UNH123 loci. All three loci presented evidence of possible null alleles. Accelerated inbreeding and genetic drift through successive generations in captivity can reduce heterozygosity and gene diversity. To investigate loss of diversity a sample taken from the Bushmans population in 1999 (N = 25) was compared with a Bushmans 2000 sample (N = 36). The comparison highlighted altered allele frequencies, a significant increase in average observed heterozygosity and a non-significant change in average expected heterozygosity using the UNHI04 and UNH123 loci. Calculation of genetic distances and phylogenetic comparisons between the populations provided insight into the degree of management required in conserving genetic diversity in natural populations of Mozambique tilapia. UPGMA and Neighbour-Joining techniques were used to construct phylogenetic trees using Dm and ({)~)2 distance matrices. Clustering of populations appeared to reflect geographic locality of the source populations, however certain populations were not congruent with geography. Mantel tests were used to expose a possible association between genetic distance matrices generated from each individual locus. An association would support a geographic background to population genetic structure. The Mantel tests did not provide conclusive evidence. Mantel tests for association between the combined locus Dm and (81l)2 genetic distance matrices and a geographic distance matrix were similarly non-significant. Multi-dimensional scaling (MDS) plots of Euclidean distance values for Dm and (81l)2 matrices presented a two-dimensional view of the genetic distance data. The degree of similarity with the UPGMA and Neighbour-Joining tree-clustering pattern was higher for the (81l)2 than for the Dm MDS plots. Scatter plots indicated a reliable non-linear correlation between Euclidean distance and genetic distance for the two-dimensional MDS. The micro satellite markers employed in this research provided molecular information needed for complimenting a co-study on quantitative genetic evaluation of the twelve populations. The quantitative co-study provided measures of average length and weight gain indices for the populations based on progeny growth trials. No significant correlation of average heterozygosity (gene diversity) with either average weight or length gain was found. The significant genetic diversity and structure present between the twelve populations provided rationale for implementing strategies to conserve natural 0. mossambicus populations as genetic resources, and manage captive populations for long term maintenance of genetic diversity. / AFRIKAANSE OPSOMMING: Die verstaffing van groot alleliese variasie deur DNA mikrosateliete maak van hulle gerieflike merkers vir navorsing in 'n verskeidenheid van velde wat gebruik maak van populasie genetiese gereedskap, ingesluit akwakultuur en bewarings genetika. Twaalf 0. mossambicus populasies wat verkry was vanuit die natuur, in gevangeneskap en ingevoerdes, van Suidelike Afrika was getoets vir genetiese variasie by tien verskillende CA-herhalende mikrosateliet loci. Drie van die loci - UNHI04, UNHlll en UNH123 - is op grootskaal getoets en volgens In model van Mendeliese oorerwing geinterpreteer. Die data was ontleed volgens genetiese struktuur en vlakke van genetiese variasie, die effek wat bestuur strategie in gevangeneskap op genetiese diversiteit in opeenvolgende generasies uitgeoefen het, so wel as die aard van die filogenetiese verhoudings wat teenwoordig is tussen die populasies. "Exact" toetse is uitgevoer deur gebruik te maak van Monte Carlo tipe veelvuldige hermonsterinsamelings tegnieke en F-statistieke is gebruik vir die deteksie en kwantifisering van die genetiese struktuur tussen die twaalfpopulasies. Die Exact toets X2 (P < 0.001), 'n FST van 0.27 (P < 0.001), SST van 0.26, RsT van 0.28, en 'n <DST van 0.17 gee almal 'n indikasie van betekenisvolle strukturering tussen die populasies. Die genetiese struktuur bevestig die beleid dat die populasies behou moet word as aparte genetiese voorraad, in aparte tenke, om te verseker dat die unieke genetiese materiaal behoue bly om akwakultuur variante te ontwikkel. Populasies het ook betekenisvolle verskuiwings van die Hardy Weinberg ekwilibrium getoon, wat gekarakteriseer word deur 'n algemene verlaging van heterosigositeit oor die loci. Nul allele word dikwels aanbeveel om in mikrosateliet studies groot bydraes te maak tot hetersigotiese defekte. Om vir nul allele te toets was twee gekontroleerde kruisings van 0. mossambicus gemaak. Die nageslag van elke kruising was getoets vir verwagte ouer alleliese verhoudings by die UNHI04, UNHlll en UNH123 loci. Al drie loci het getoon dat dit moontlike nul allele kan wees. Versnelde inteling en genetiese drywing deur opeenvolgende generasies in gevangeneskap kan die heterosigositeit en diversiteit verminder. Om die vermindering van diversiteit te toets was 'n monster van die Busmans 1999 (N=25) populasie vergelyk met 'n monster van die Bushmans 2000 (N=36) populasie. Die vergelyking het veranderde alleel frekwensies, 'n betekenisvolle vermeerding in gemiddelde waargeneemde heterosigositeit en 'n onbetekenisvolle verandering in gemiddelde verwagte heterosigositeit getoon deur gebruik te maak van die UNHI04 en UNH123 loci. Berekening van genetiese afstande en filogenetiese vergelykings tussen die populasies het nuwe insig gegee oor die graad van bestuur wat nodig is om genetiese diversiteit in die natuurlike populasies van 0. mossambicus tilapia te behou.UPGMA en Neighbour-Joining tegnieke was gebruik om filogenetiese bome op te stel deur gebruik te maak van Dm en (OIl)2 afstand matrikse. Populasie bondeling het geblyk om geografiese lokaliteit van die bron populasies te toon, alhoewel van die populasies nie met die geografiese lokaliteit ooreengestem het nie. Mantel toetse is gebruik om 'n moontlike assosiasie tussen genetiese afstand matrikse wat verkry is van elke loci bloot te stel. 'n Assosiasie sou 'n geografiese agtergrond tot populasie genetiese struktuur steun. Oortuigende bewys is nie deur die Mantel toetse verskaf nie. Mantel toetse vir assosiasie tussen die gekombineerde loci Dm en (OJ..l)2 genetiese afstand matrikse en In geografiese afstand matriks was ook onbetekenisvol. 'n Tweedimensionele beskouing van die genetiese afstand data is voorgestel deur multidimensionele skaal (MDS) grafieke van Euclidean afstand waardes van die Dm en (OJ..l)2 matrikse te teken. Die graad van ooreenstemming met die UPGMA en Neighbour-Joining boom samevoeging patroon was hoër vir die (OJ..l)2 as vir die DmMDS grafieke. Verspreiding grafieke het 'n vertroubare nie-liniêre korrelasie tussen Euclidean afstande en genetiese afstande vir die twee-dimensionele MDS grafieke getoon. Die mikrosateliet merkers wat in die studie gebruik was het molekulêre informasie verskaf wat nodig is vir 'n komplimentêre studie oor die kwantitatiewe genetiese evalueering van dié twaalf populasies. Die kwantitatiewe studie het afmetings van gemiddelde lengte en gewig vermeerdering van die populasies verskaf gebaseer op nageslag proewe. Geen betekenisvolle korrelasie van gemiddelde hetersigositeit (geen diversiteit) was getoon met óf gemiddelde gewig óf lengte vermeerdering. Die betekenisvolle genetiese diversiteit en struktuur teenwoordig tussen die twaalf populasies het rede gegee om strategieë te implimenteer om natuurlike 0. mossambicus populasies te konserveer as genetiese bronne en om populasies in gevangeneskap te bestuur vir langtermyn instandhouding van genetiese diversiteit.
119

Molecular phylogenetics and phylogeography of sand lizards, Pedioplanis (Sauria: Lacertidae) in southern Africa

Makokha, Jane Sakwa 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: The present study aims to determine the phylogenetic relationships among the sand lizards, Pedioplanis. In addition, a single mitochondrial gene is used to investigate the geographic genetic structure of the widey distributed P. burchelli. With 11 species, Pedioplanis is the most speciose genus among the southern African genera of the family Lacertidae. All the species are restricted to the subcontinent with the exception of three (P. namaquensis, P. undata and P. benguellensis), which extend their range northwards into Angola. A total of 2200 nucleotide positions derived from two mitochondrial markers (ND2 and 16S rRNA) and one nuclear gene (RAG-1) are used to determine the phylogenetic relationships among ten of the eleven Pedioplanis species. The first well resolved gene tree for the genus, drawn from 100 individuals, is presented and this is largely congruent with a phylogeny derived from morphology. Contrary to some previous suggestions, Pedioplanis forms a monophyletic assemblage with Heliobolus and Nucras. The genus Pedioplanis is monophyletic with P. burchelli/P. laticeps forming a sister clade to all the remaining congeners. Two distinct geographic lineages can be identified within the widespread P. namaquensis; one occurs in Namibia, while the other occurs in South Africa. The “P. undata” species complex is monophyletic, but one of its constituent species, P. inornata, is paraphyletic. Relationships among the subspecies of P. lineoocellata are much more complex than previously documented. An isolated population previously assigned to P. l. pulchella is paraphyletic and sister to the three named subspecies. The phylogeny identifies two biogeographical groupings that probably diverged during the mid-Miocene. The development of the Benguella Current could have initiated isolation mechanisms associated with changes in habitat that could have generated barriers and played a role in the evolution of this group. At the lower taxonomic level, the mtDNA phylogeographic structure of the wide spread P. burchelli in South Africa reveal at least six distinct clades that are geographically partitioned. The first one is restricted to the eastern mountains along the Great Escarpment (GE). The next three are found along the Cape Fold Mountains (CFM): the north-west CFM, central CFM and eastern CFM. The fifth one shares samples from central CFM and GE. The last clade is restricted to the eastern central mountains of the GE. These six geographic groupings are genetically divergent from each other and they started separating in the early Pliocene period. Phylogeographic studies on other taxa in the region have found different levels of genetic structuring among or within taxa. The fact that P. burchelli is restricted to high altitude areas could have resulted in limited dispersal and consequently contributed to its geographic structure. However, the exact cause of the pattern obtained is not readily apparent. Habitat fragmentation in the past is probably one of the most influential factors shaping the genetic distribution of the species across South Africa. The inclusion of nuclear markers will shed more light on the evolutionary history of P. burchelli in South Africa. / AFRIKAANSE OPSOMMING: Die huidige studie stel ten doel om ‘n filogenie daar te stel vir die Sand akkedisse, Pedioplanis. ‘n Enkele mitochondriale geen is ook gebruik om die geografiese genetiese struktuur van die wydverspreide P. burchelli vas te stel. Met 11 spesies is Pedioplanis die mees spesieryke genus onder die suidelike Afrika genera wat aan die Lacertidae familie behoort. Al die spesies is beperk tot die subkontinent met die uitsondering van drie (P. namaquensis, P. undata en P. benguellensis), wat ‘n uitgebreide verspreiding het noordwaarts tot in Angola. ‘n Totaal van 2200 nukleotied posisies wat afkomstig is van twee mitochondriale merkers (ND2 en 16S rRNA) en een nukluêre geen (RAG-1) is gebruik om die filogenetiese verwantskappe tussen 10 van die 11 Pedioplanis spesies vas te stel. Die eerste goed geondersteunde geen boom vir die genus, gebasseer op 100 individue, is verkry en dit is meestal ooreenstemmend met ‘n filogenie gebasseer op morfologie. In teenstelling met sekere voorstelle van die verlede vorm Pedioplanis ‘n monofiletiese groep tesame met Heliobolus en Nucras. Die genus Pedioplanis is monofileties met P. burchelli/P. laticeps wat ‘n suster groep vorm van al die oorblywende lede van die genus. Twee herkenbare geografiese lyne kan geidentifiseer word in die wydverspreide P. namaquensis; een kom in Namibia voor, terwyl die ander een in Suid Afrika voorkom. Die “P. undata” spesies kompleks is monofileties, maar een van die spesies wat deel uitmaak van die groep, P. inornata, is parafileties. Verwantskappe tussen die subspesies van P. lineoocellata is meer kompleks as wat aanvanklik aanvaar is. ‘n Geisoleerde bevolkimg wat voorheen toegesê is aan P. l. pulchella is parafileties en verteenwoordig ‘n suster groep van die benaamde subspesies. Die filogenie identifiseer twee biogeografiese groeperings wat moontlik gedivergeer het gedurende die middel-Miocene. Die ontwikkeling van die Benguella stroom het dalk versperrings geinisiëer as gevolg van die gesamentlike veranderinge in habitat wat dalk ook ‘n rol gespeel het in die evolusie van die groep. Op die laer taksonomiese vlak het die mtDNA filogeografiese struktuur van die wydverspreide P. burchelli in Suid Afrika ten minste ses groepe aangetoon wat geografies van mekaar geskei is. Die eerste een is beperk tot die oostelike berge wat aan die Groot Eskarpement (GE) behoort. Die volgende drie word gevind in die Kaapse Vouberge (KVB): die noord-westelike KVB, sentrale KVB en oostelike KVB. Die vyfde een deel eksemplare van beide die GE en die KVB. Die laaste groep is beperk tot die oostelike en sentrale berge van die GE. Hierdie ses geografiese groepe is geneties geskei van mekaar en hulle het begin om apart te ontwikkel gedurende die vroë Pliocene periode. Ander filogeografiese studies in die area het verskillende vlakke van genetiese struktuur vertoon tussen en binne taksa. Die feit dat P. burchelli beperk is tot hoogliggende dele kon moontlik bygedrae het tot die geografiese struktuur. Die presiese oorsaak van die patroon wat verkry is, is nie ooglopend nie. Habitat fragmentasie in die verlede is moontlik een van die mees invloedrykste faktore wat die genetiese verspreiding van die spesie in Suid Afrika beinvloed het. Die insluiting van nukluêre merkers sal meer lig warp op die evolusionêre geskiedenis van P. burchelli in Suid Afrika.
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Endogenous credit money : evidence from selected developing countries

Theron, N. 04 1900 (has links)
Dissertation (PhD)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: The endogenous money theory states that the money supply responds endogenously to the demand for credit. The money supply is not exogenously determined by the central bank. The endogenous theory is associated with the Post Keynesian school. It has been tested extensively for developed countries, where it was found that the modern credit-driven world is characterised by an endogenous money supply. The contribution of the present study is to extend this analysis to developing countries, specifically twelve countries in the SADC region. To examine the applicability of the endogenous money theory to developing countries, the thesis begins with an overview of the views of the different schools of thought on the role of money. The areas of consensus and disagreement within the Post Keynesian school are discussed. The theoretical basis of the thesis is the ‘structuralist’ Post Keynesian view that money cannot be endogenous if the financial system in a country has not reached the final stages of development. The ‘structuralist’ hypothesis is tested for the SADC countries by examining the demand and supply of credit money in each country. It was found that households do not generally have full access to formal credit markets. Changes in the money supply are not determined by changes in private sector credit in many of the countries. The analysis was then extended to the institutional environment in each country. A financial institutional index was developed to facilitate comparison between the SADC countries. It was shown that South Africa is the only country in the SADC area that has a financial system that can be classified as ‘largely developed’. It is also the only country where changes in the supply of money are predominantly credit-driven. Post Keynesians maintain that the money supply is endogenous and interest rates are exogenous. Interest rate mark-ups and spreads are assumed stable over the business cycle. This notion is challenged by the ‘structuralist’ Post Keynesians. To test the theory of stable interest rate mark-ups and spreads, data for each individual country were examined. Neither interest rate spreads, nor interest rate mark-ups were found to be stable. Interest rate spreads are generally higher in developing countries than in developed countries. No clear pro- or counter-cyclical variation in spreads was found. Finally, an econometric model was developed and the links between financial development and growth were examined. By looking at 49 developed and developing countries, it was found that financial development is strongly linked to economic growth. Financial repression and high interest rate spreads cause growth to be depressed. Financial development and increased competition in the banking sector will lead to higher real economic growth rates. In an environment where the financial system has not reached the stage where money is endogenous, the lack of financial institutional development stifles economic growth. / AFRIKAANSE OPSOMMING: Die teorie van ‘n endogene geldvoorraad aanvaar dat die aanbod van geld endogeen reageerop die vraag na krediet. Die geldvoorraad word nie eksogeen bepaal deurdie sentrale bank nie. Die endogene gedvoorraad teorie word geassosieer met die Post Keynesiaanse skool. Dit is reeds getoets vir ontwikkelde lande, waar die bevinding was dat ‘n endogene geldvoorraad ‘n eienskap is van ‘n moderne kredietgedrewe wereld. Hierdie tesis maak ‘n bydrae deur die analise uit te brei na ontwikkelende lande, spesifiek twaalf lande in die SADC streek. Om die toepasbaarheid van die endogene geldvoorraad vir ontwikkelende lande te toets, begin die tesis met ‘n oorsig van die verskillende denkskole se sienings oor die rol van geld. Die areas waar Post Keynesiane ooreenstem en verskil word bespreek. Die teoretiese basis van die tesis is die ‘strukturalistiese’ Post Keynesiaanse siening dat die geldvoorraad nie endogeen kan wees indien die finansiele sisteem in ‘n land nog nie die finale ontwikkelingstadia bereik het nie. Hierdie hipotese van die ‘strukturaliste’ word getoets vir die SADC lande deur te kyk na die vraag na en aanbod van krediet in elke land. Daar is bevind dat huishoudings oor die algemeen nie volledige toegang het tot formele kredietmarkte nie. Veranderinge in die geldvoorraad word nie in al die lande veroorsaak deur veranderinge in privaat sektor kredietverlening nie. Hierdie analise word dan uitgebrei na die institusionele omgewing in elke land, ‘n Finansiele institusionele indeks is ontwikkel om vergelyking tussen die SADC lande moontlik te maak. Daar is bevind dat Suid Afrika die enigste land is met 'n finansiele sisteem wat geklassifiseer kan word as ‘grotendeels ontwikkeld’. Dit is ook die enigste land waardie geldvoorraad beduidend kredietgedrewe is. Post Keynesiane glo dat die geldvoorraad endogeen is en rentekoerse eksogeen. Rentekoersmarges word gesien as stabiel oor die konjunktuursiklus. Hierdie aanname word bevraagteken deur die ‘strukturalistiese’ Post Keynesiane. Die teorie van stabiele rentekoersmarges word getoets deur te kyk na data vir elke individuele land. Die bevinding is dat rentekoersmarges nie stabiel is nie. Marges is oor die algemeen hoer in ontwikkelende lande as in ontwikkelde lande. Daar is geen duidelike pro- of kontrasikliese variasies in rentekoersmarges gevind nie. Laastens is ‘n ekonometriese model ontwikkel om die skakels tussen finansiele ontwikkeling en groei te ondersoek. Deur te kyk na 49 ontwikkelde en onontwikkelde lande, is daar bevind dat finansiele ontwikkeling en groei ‘n sterk verband toon. Finansiele onderdrukking en hoe rentekoersmarges lei tot laer ekonomiese groei. Finansiele ontwikkeling en groter mededinging in die bank sektor sal lei tot hoer reele ekonomiese groeikoerse. In ‘n omgewing waar die finansiele sisteem nog nie die stadium bereik het waar geld endogeen is nie, sal die gebrek aan finansiele institusionele ontwikkeling ekonomiese groei benadeel.

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