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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.
91

Solar cycle effects on GNSS-derived ionospheric total electron content observed over Southern Africa

Moeketsi, Daniel Mojalefa January 2008 (has links)
The South African Global Navigation Satellite System (GNSS) network of dual frequency receivers provide an opportunity to investigate solar cycle effects on ionospheric Total Electron Content (TEC) over the South Africa region by taking advantage of the dispersive nature of the ionospheric medium. For this task, the global University of New Brunswick Ionospheric Modelling Technique (UNB-IMT) was adopted, modified and applied to compute TEC using data from the southern African GNSS Network. TEC values were compared with CODE International GNSS services TEC predictions and Ionosonde-derived TEC (ITEC) measurements to test and validate the UNB-IMT results over South Africa. It was found that the variation trends of GTEC and ITEC over all stations are in good agreement and show pronounced seasonal variations with high TEC values around equinoxes for a year near solar maximum and less pronounced around solar minimum. Signature TEC depletions and enhanced spikes were prevalently evident around equinoxes, particularly for a year near solar maximum. These observations were investigated and further discussed with an analysis of the midday Disturbance Storm Time (DST) index of geomagnetic activity. The residual GTEC – ITEC corresponding to plasmaspheric electron content and equivalent ionospheric foF2 and total slab thickness parameters were computed and comprehensively discussed. The results verified the use of UNB-IMT as one of the tools for ionospheric research over South Africa. The UNB-IMT algorithm was applied to investigate TEC variability during different epochs of solar cycle 23. The results were investigated and further discussed by analyzing the GOES 8 and 10 satellites X-ray flux (0.1 – 0.8 nm) and SOHO Solar Extreme Ultraviolet Monitor higher resolution data. Comparison of UNB-IMT TEC derived from collocated HRAO and HARB GNSS receivers was undertaken for the solar X17 and X9 flare events, which occurred on day 301, 2003 and day 339, 2006. It was found that there exist considerable TEC differences between the two collocated receivers with some evidence of solar cycle dependence. Furthermore, the daytime UNB TEC compared with the International Reference Ionosphere 2001 predicted TEC found both models to show a good agreement. The UNB-IMT TEC was further applied to investigate the capabilities of geodetic Very Long Baseline Interferometry (VLBI) derived TEC using the Vienna TEC Model for space weather monitoring over HartRAO during the CONT02 and CONT05 campaigns conducted during the years 2002 (near solar maximum) and 005 (near solar minimum). The results verified the use of geodetic VLBI as one of the possible instruments for monitoring space weather impacts on the ionosphere over South Africa.
92

A framework to elicit user requirements for information systems: a localised participatory approach from Southern Africa

Tyukala, Mkhululi January 2014 (has links)
The “What” and “Why” in information system development in resource restricted environments is already well covered in literature. However, the “How” to do it still has not been explored. This thesis reports on the development of a locally flavoured participatory user requirements elicitation framework for the development of information systems in resource restricted environments. It uses existing participatory design practices, user requirements elicitation literature and local participatory norms and traditions to achieve this. In doing so, it takes a step towards the way information systems could be developed in resource restricted environments. The topic of this thesis is mainly motivated by the recent calls in existing literature for developing countries to start developing their own information systems in order to address their own requirements. Accordingly, and to lay a foundation towards the realisation of this goal, this research is positioned within the user requirements elicitation region of information systems development. Current user requirements elicitation methods use traditional methods where experts/designers ask system users questions through interviews or learn about their environment through observations. This research proposes a shift from this approach to one that not only views users as equal partners in the elicitation process but in the whole information systems development process. This is in the spirit of participatory design, which was developed in Scandinavia more than four decades ago. Further, recent research in participatory design emphasises the importance of its contextual nature and concedes that there is no single best practice for participatory design in information systems that applies to all contexts. This research explores the information systems development discourse in resource restricted environments in Africa. Its purpose is to enhance understanding of the local contexts, thus providing new insights on how to develop a framework that speaks to local challenges using norms and traditions in order to develop information systems that address local requirements. Thus, the main contribution of this research lies in laying a foundation for a locally flavoured participatory approach for information systems development in resource restricted environments. It contributes to the existing information systems development, participatory design and user requirements elicitation body of knowledge by developing a framework for participatory user requirements elicitation. In addition, it contributes to the participatory design body of knowledge by introducing an age-old African participatory decisionmaking approach to the academic participatory design community. In doing so, it adopts the meaning of participation from an African value system point of view, which is something that has only been previously explored in the Nordic countries and North America. Finally, recommendations for the application, limitations and avenues for further research are incorporated into the findings of this research.
93

The impact of economic freedom on economic growth in the SADC

Gorlach, Vsevolod Igorevich January 2014 (has links)
The role of institutions – economic freedom – is a critical determinant of economic growth, yet the global distribution of economic freedom is skewed. Economic freedom focuses on personal choice, the ability to make voluntary transactions, the freedom to compete and the security of property rights. The SADC is attempting to alleviate poverty and achieve sustainable development and economic growth. This thesis illustrates that economic freedom, in aggregate, and on an individual component basis, drives economic growth. The annual data for the 12 SADC counties from 2000 to 2009 are used to construct a panel data model to conduct the empirical analyses. Cross-sectional effects, as well as time (period) effects, are valid; and thus, a two-way error-component model is estimated. The Hausman test showed the regressors to be endogenous and correlated with the error term. The Pesaran CD test, suitable for dynamic panels, determined that cross-sections are interdependent; and the cross-correlation coefficient indicated a relatively weak, yet substantial, correlation. The LSDV two-way error-component model is re-estimated using the Driscoll and Kraay standard errors and time-demeaned data to correct for cross-sectional dependence. Given the endogeneity between the idiosyncratic disturbance term and the regressors, the presence of heteroskedasticity and serial correlation, as well as the interdependence amongst the cross-sections, the econometric model is then estimated using the two-step system general method of moments with forward orthogonal deviations – instead of differencing. The results meet all the post-estimation diagnostic requirements: the Arellano and Bond test for second-order serial correlation fails to reject the null hypothesis of no autocorrelation; theSargan test for over-identification fails to reject the null hypothesis that the over-identification restrictions are valid, and the difference-in-Hansen test fails to reject the null hypothesis that the instrument subsets are strictly exogenous. The empirical results confirm the a priori expectations. Economic freedom is a positive and significant driver of economic growth. Investment and economic openness are positively related to growth, whereas government debt decreases growth. Government consumption is an insignificant driver of a country’s growth. The Granger causality test confirmed the direction of causality; economic freedom precedes economic growth; and it is possible for the SADC to improve their growth rates by becoming economically freer. The coefficient of adjustment derived from the error-correction model indicates that the dynamic system takes approximately two years to adjust to the long-run structural level. The Koyck Transformation indicates that the relationship between economic freedom and growth is intertemporal, requiring a lag structure. An impulse-response function shows that a permanent, positive ‘shock’ to economic freedom results in an increase in economic growth, although the extent differs for each country, as well as for the different freedom components. The five individual economic freedom components are all highly significant and positive drivers of growth; however, the magnitude of the elasticity parameters varies. The causality amongst the components indicates that bidirectional causality is present. Therefore, improving economic freedom in one area improves economic freedom in another, creating a multiplier effect.
94

Textile and clothing industry competitiveness in the Southern African region

Mwamayi, Kibunji Adam January 2013 (has links)
This is a study of the relationship between approaches to people management and competitiveness, by examining the case of the textile and clothing industry in Southern Africa. The textile and clothing industry has historically played a major role in many national economies (including many southern African countries) contributing not only to overall economic growth, but also to the creation of significant numbers of relatively well-paid jobs. In the Southern African Region (SAR), the textile and clothing industry has undergone many structural pressures in the face of increased cheap imports from South-East Asian countries – above all, China and Bangladesh - which have resulted in the closure of many firms, and the significant downsizing of many survivors. This study seeks to explore the relationship between HR practice and organizational sustainability in the textile and clothing industry in Southern Africa region, with a particular emphasis on the cases of three countries: South Africa, Mauritius and the Democratic Republic of the Congo. Whilst at very different stages of national development, and with distinct political and developmental histories, all three countries were subject to active industrial policies, including the development of national clothing and textile industries. Again, all have faced the challenge of sustaining these industries in the face of liberalization and intensive competition from the Far East. This study is based on a multi-method approach, combining in-depth interviews with national industry surveys, and the usage of relevant documentary sources. It takes cognizance of the increasing relevance of new HRM practices and discourses to the growing field of Development Studies in the 21st century. The existing HRM literature suggests that there are a number of alternative people management strategies through which firms may secure their competitiveness, most notably strategic approaches to hard HRM (which treats people as an instrument to be strategically deployed to promote competitiveness), soft HRM (which promotes cooperative approaches to managing people) and traditional labour repression (managing people simply as a cost, to be managed in a short-term, un-strategic manner). The literature on HRM in Africa has suggested an alternative paradigm, which combines autocratic paternalism with elements of communitarianism. This study found that the bulk of firms encompassed by the study employed HR policies that recognizably fell within the soft HRM paradigm, enabling high value added production. However, an important exception lies in the area of security of tenure: firms tended to combine high levels of employee involvement and participation; as well as a commitment to human resource development, along with a persistent reliance on the usage of redundancies to adjust changes in the relative need for labour. Hence, this study highlights the limitations of theoretical approaches which see HR strategies as being necessarily coherent and self-reinforcing. Firms may broadly adhere to one approach, whilst adopting aspects of another as needs arise and in response to external pressures. An important exception to this was Mauritius, in which security of tenure appeared to be stronger, perhaps owing to the greater ease of enforcing regulations against illegal imports in a relatively small island country by allowing firms to plan for the future with greater confidence. In contrast, firms in South Africa were characterized by much lower security of tenure, against a backdrop of declining profits, reflecting the competitive challenges posed not only by legitimate low cost imports, but also illegal imports and the proliferation of rural sweatships. One again, this study highlights the relative fragility of the position of many firms and the continued importance of governmental support, most notably in terms of export incentives, support and facilitation in the adoption of new technologies, as well as better policing against illegal imports.
95

Feeding ecology and social organisation of honey badgers (Mellivora capensis) in the southern Kalahari

Begg, Colleen Margeret 28 November 2005 (has links)
The lack of fundamental biological information on the honey badger Mellivora capensis and its vulnerable conservation status were the motivating factors behind this study. A study population of 25 individuals (12 females; 12 males) was radio-marked in the Kgalagadi Transfrontier Park (KTP), South Africa. Through a combination of radio telemetry and visual observations (5 244 h) of nine habituated individuals (five females; four males), the feeding ecology, scent marking and social behaviour of the honey badger were investigated. The honey badger is a solitary, generalist carnivore with strong seasonal differences in diet. In support of optimal diet theory, the cold dry season diet is characterized by low species richness, low foraging yield, high dietary diversity and increased foraging time while the reverse is true in the hot wet and hot-dry seasons. The honey badger appears to shift between alternative prey species depending on their availability on a seasonal and daily level. The daily activity patterns of both sexes show a strong seasonal shift from predominantly nocturnal activity in the hot-wet and hot-dry season to more diurnal activity in the cold-dry season and this appears to be primarily affected by temperature. Despite marked sexual size dimorphism (males a third larger than females), no intersexual differences in diet or foraging behaviour were observed, but there were sexual and in males age-related differences in movement patterns, scent marking and social behaviour. The honey badger appears to have a polygynous or promiscuous mating system, but did not fit the general mustelid pattern of intrasexual territoriality. Instead, adult males had extensive overlapping home ranges (548 km2) that encompassed the smaller, regularly spaced home ranges of the females (138 km2) and young males (178 km2). Receptive females are an unpredictable and scare resource in space (large home ranges) and time (no breeding season) with a long time to renewal (inter-birth interval > 1 year). As a result adult males adopt a roaming rather than a staying tactic with competition for access to the mating burrow mediated by a dominance hierarchy loosely based on age, mass and testes size. The hierarchy appears to be maintained through regular aggressive and agonistic interactions and scent marking. Data suggest that latrine scent marking in adult males is related to advertising social status and maintaining the dominance hierarchy though “scent matching”. In females and young males latrine visits are rare, but token urination is common and its association with foraging behaviour suggests that it mediates spatio-temporal separation and/or resource utilization. Interspecific interactions between the honey badger and other mammalian and avian predators were common and included intraguild predation and interspecific feeding associations between the honey badger and seven other species (two mammals; five birds). The most common foraging associations were observed between the honey badger and the pale chanting-goshawk Melierax canorus and black-backed jackal Canis mesomelas. These associations appear to be commensalisms, with associating species benefiting from increased hunting opportunities and intake rate but no significant costs or benefits to the honey badger. Copyright 2001, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Begg, CM 2001, Feeding ecology and social organisation of honey badgers (Mellivora capensis) in the southern Kalahari, DPhil thesis, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-11282005-145818 / > / Thesis (DPhil (Zoology))--University of Pretoria, 2001. / Zoology and Entomology / unrestricted
96

An examination of palaeo-sea surface temperatures and thier influence on Southern African palaeoclimates over the last 20000 years

Barbafiera, Mario 14 July 2016 (has links)
A Dissertation Submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, for the Degree of Master of Science Johannesburg, 1997 / The palaeoclimate of southern Africa for the last twenty thousand years is investigated through the production of palaeoclimate maps based on an analysis of literature and data from the ongoing PASH project. The trends from the maps are compared with published reviews and modelling studies of the region' s palaeoclimates, and are contextualised in terms of global palaeoceanographic and palaeoclimatic dynamics. The changes evident in the past climate of southern Africa tend to mirror global climate changes, however, evidence exists that the timing of climate changes between the two hemispheres are not quite synchronous, and may 110tfit present theories of global palaeoclimate dynamics,
97

Extractives of three southern African medicinal plants.

Page, Bronwen Ann. January 1998 (has links)
In this investigation the chemistry of three southern African plants used for medicinal purposes was investigated. The plants were Dioscorea dregeana, Avonia rhodesica and Equisetum ramossisimum. Extracts of all three of these plants have been found to be active on the central nervous system. The structures of the compounds isolated were determined by using 1H and 13C n.m.r., i.f., UV-VIS, - mass spectroscopy and chemical methods. D. dregeana yielded two alkaloids and three aromatic compounds. A. rhodesica contained a large amount of wax which was analysed by GC-MS and its distribution and physical nature on the surface of the leaves was determined by SEM (scanning electron microscopy). This plant also contained two sterols. Equisetum ramossisimum extracts contained a carotenoid and several porphyrins, as well as large amounts of silica. A DTSA X-ray microanalysis system (which was a component of the scanning electron microscope) was used to determine the distribution of silica in the stem. / Thesis (M.Sc.)-University of Natal, Durban, 1998.
98

Modelling systems for an effective humanitarian supply chain for disaster relief operations in the SADC region

Baraka, Jean-Claude Munyaka January 2014 (has links)
Submitted in fulfillment of the requirements of the degree of Master of Technology: Industrial Engineering, Durban University of Technology, Durban, South Africa, 2014. / The SADC region has seen both man-made and natural disasters killing over 90 thousand people and affecting millions in the past 33 years. Most of these deaths were as a result of lack of infrastructure and preparedness. Looking at the challenges for providing relief to victims/evacuees throughout the entire disaster and post-disaster periods in the region, the emphasis of this thesis is on last mile transportation of resources, victims, emergency supplies, aiming to optimize the effectiveness (quick­I response) and efficiency (low-cost) of logistics activities including humanitarian supply chain. A survey was used for data collection. Statistical analysis helped determine the impact of disaster relief chains and lead to the development of a mathematical model that shall equip the region with mechanisms for response and recovery operations. An EXCEL optimization tool was used to find the optimal way of transporting relief in the region in case of a disaster. / PDF Full-text unavailable. Please refer to hard copy for Full-text / M
99

Avian fruit selection and sugar preferences.

Ally, Ebrahim. January 2010 (has links)
It has been suggested that fruit features such as nutrient content, size and colour have co-evolved with dispersal agent behaviour, physiology and morphology. Avian nectarivore feeding ecology is relatively well studied; however, less is known about fruit selection in avian frugivores. Previous work highlights the importance of individual factors that contribute towards fruit preferences, but few studies bring these factors together. Consequently the aim of this dissertation was to attempt this in terms of frugivory by investigating behavioural, physiological and morphological aspects of fruit selection in generalist avian dispersers. This was achieved by manipulating the nutritional content, size and colour of fruits (artificial fruits) under controlled conditions. The first part of the dissertation addresses physiological aspects of fruit selection in Red-winged Starling Onychognathus morio, Speckled Mousebird Colius striatus and Dark-Capped Bulbul Pycnonotus tricolor. Assimilation efficiency of birds fed glucose and sucrose diet treatments of varying concentration was observed. All study species showed high apparent assimilation efficiency irrespective of artificial fruit sugar concentration and type (with the exception of Red-winged Starlings on an all sucrose diet). The second part of the dissertation addresses behavioural aspects of fruit selection in the same three species by observing selective preferences between glucose and sucrose fruits of varying concentration and molarity. While Mousebirds displayed no preference for any of the diet treatments, Bulbuls occasionally favoured glucose diets over sucrose diets and Starlings always favoured glucose diets over sucrose diets. Another behavioural aspect of fruit selection was addressed in the third part of the dissertation. Colour preferences of Red-winged Starling and Speckled Mousebird were observed. Although study species did not conform to trends by favouring black and red fruits, they did show avoidance of green fruits and (Starlings) presented evidence of learning. A morphological aspect of fruit selection is presented in the fourth part of the dissertation. Starlings, Bulbuls and Mousebird beak morphology was measured to investigate if this has an effect on fruit size preferences. Starlings with the largest beak dimensions were more selective of fruit size classes than Bulbuls and Mousebirds which displayed the importance of feeding method (thrashing/swallowing/mashing) to compensate for larger fruit sizes. The final section of this dissertation is a synthesis of the observed behavioural, physiological and morphological aspects of fruit selection in Red-winged Starlings, Dark-capped Bulbuls and Speckled-Mousebirds. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
100

Integrated physiology and behaviour of Thallomys nigricauda along an aridity gradient.

Coleman, Joy Carol. January 2008 (has links)
Climate change predictions suggest that the continent most vulnerable to climate change is Africa. The impacts of potential changes which include increases in air temperatures and rainfall variability are negative with potential species extinctions projected throughout southern Africa. A number of climate models have been applied to examine the consequences of climate change for ranges of South African animal species. One such model frequently predicted range shifts from west to east, which is realistic considering the marked aridity gradient in an east-west direction across the country, but the authors suggested that these shifts may not be as marked if species are able to use physiological and behavioural methods to adapt to an increase in aridity. Information on the degree to which behavioural and physiological flexibility affect species range in southern Africa is scant which is surprising given its importance with regard to climate change. Thallomys nigricauda occurs along an east-west aridity gradient in southern Africa, inhabiting mesic, semi-xeric and xeric regions. One would expect phenotypic flexibility in physiological and behavioural traits in response to the diverse environmental conditions to be related to the success and range of the species. The wide distribution and arboreal habits, suggesting that T. nigricauda is exposed to greater extremes of temperature than fossorial rodents, makes T. nigricauda an ideal species to test this assumption. Hence I expected that T. nigricauda would exhibit variation in physiological and behavioural traits measured along an aridity gradient. This has important implications in predicting the survival of small mammal species in the light of climate change in southern Africa. Thallomys nigricauda were live-trapped in winter 2006 and 2007 and summer 2007 using Elliot traps in three sites: mesic site Weenen Game Reserve (KwaZuluiv Natal Province, South Africa); semi-xeric site Haina Game Farm (Botswana) on the northern boundary of the Central Kalahari Desert and xeric site Molopo Nature Reserve (southern Kalahari savannah, North-West Province, South Africa). I studied the home-range size of T. nigricauda by radiotracking 12 males and 16 females in winter 2006, 2007 and summer 2007. Home ranges were estimated using 100% and 95% minimum convex polygons and 95% and 50% fixed kernels. Home ranges varied widely, from 166 to 80199m2 for males and from 46 to 8810m2 for females. Males had larger home ranges than females, which supports a promiscuous mating system reported for the species. Although range size was reduced in both sexes in winter, this was not significant. I found no significant difference in home range size along the aridity gradient. It is suggested that a combination of precipitation, habitat productivity and breeding system influences the size of home range of the species, and that this species displays phenotypic flexibility in terms of its behavioural responses to these factors. I measured the urine concentrating ability (UCA), as indicated by urine osmolality and relative medullary thickness (RMT), and water turnover rate (WTR) of T. nigricauda. There was no significant difference in RMT between sites or sex and no difference in osmolalities when site, season and sex were taken into account. In addition, specific WTR was not significantly influenced by season. Lack of significant differences could be the result of the high degree of individual variation in the traits measured, an indication of the flexibility in UCA and WTR. However, higher urine osmolality and lower WTR’s were recorded in the dry winter months. I quantified the thermal environment perceived by a small, arboreal, mammalian endotherm using a number of methods at three study sites in winter and summer. Our area of interest was how well these methods accurately portrayed the actual temperatures that small mammals are exposed to. Temperature differences between the methods were largest during the midday, when temperatures were highest. All methods recorded a greater range of temperatures during photophase than during scotophase. Black-bulb and model temperatures produced more accurate, rapid measurements when compared to measurements produced by direct temperature recording devices, particularly during photophase, when solar radiation is the major influence of heating. Other methods lagged behind black-bulb measurements. Although the mean temperatures of some of the methods were significantly different, there was a high degree of correlation between all methods, even after randomization and generation of 25% and 10% subsamples. Computed thermal indices and blackbulb temperatures produced similar thermal profiles. In studies requiring accurate time series measurements, it is suggested that black-bulb or copper models be employed rather than direct temperature recording devices. Simpler measurement devices would suffice for studies requiring an estimate of the temperature variation and trends in the microclimate of small mammalian endotherms, particularly arboreal or cavity dwelling species. In the wild, across an aridity gradient, I measured abdominal body temperarture (Tb) of T. nigricauda using implanted iButtons®. All but three T. nigricauda displayed significant 24 h Tb rhythmicity. The Tb range for free-living T. nigricauda was 32.33-40.63 oC (n = 13) and 32.69-40.15 oC (n = 17) in winter and summer respectively. Although there was variation in Tb profiles, T. nigricauda generally displayed a bimodal distribution of Tb, with high and low Tb values during scotophase and photopase respectively. Body temperature range was significantly greater in winter, when T. nigricauda reduced its minimum Tb. It was shown that the maximum amplitude of circadian rhythms of body temperature was on average 259.6% of expected values. To determine the extent to which the microclimate of T. nigricauda cavities assists in the maintenance of Tb, I measured the temperatures of cavities across the gradient, providing an indication of the degree of buffering provided by refugia. I measured the temperatures of shallow and deep regions of cavities using iButtons® in summer and winter and recorded operative and shade temperatures for comparison. Compared with operative temperature, cavities had stable microclimates, displaying smaller ranges in temperature. Mean minimum and maximum cavity temperatures differed significantly to operative temperature and between seasons, whereas there was no significant difference between shallow and deep measurements in cavities. Differences in the buffering capacities of the cavities between seasons were not significant. To determine whether T. nigricauda alter its length of exposure in response to lower ambient temperatures in winter as a means of maintaining Tb, I measured the activity of T. nigricauda, defined as the proportion of fixes outside the home cavity of the individual. Males spent a greater proportion of the active phase away from their home cavity in summer, and significantly in winter when compared with females, but there were no differences between seasons. It is suggested that T. nigricauda realize energy savings by lowering its Tb during their rest phase during the day, allowing them to maintain nocturnal activity and overall energy balance. Thus, besides the larger male home range, a result of the reproductive pattern, the physiological and behavioural traits of T. nigricauda measured in this study did not differ between aridity sites or seasons. The results of this study, in highlighting the variation in physiological and behavioural responses of subpopulations of T. nigricauda to diverse conditions, suggest that this variation is due to phenotypic flexibility. Understanding the extent and nature of this flexibility is critical to our comprehension of the consequences climate change. By defining the presence and extent of intraspecific variation in physiology and behaviour, this study resolved the necessary first step towards this understanding for the widely distributed T. nigricauda in southern Africa. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.

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