Geology of the Kroonstad kimberlite cluster, South Africa
- Authors: Howarth, Geoffrey H
- Date: 2010
- Subjects: Geology -- South Africa -- Kroonstad , Kimberlite -- South Africa -- Kroonstad
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4961 , http://hdl.handle.net/10962/d1005573 , Geology -- South Africa -- Kroonstad , Kimberlite -- South Africa -- Kroonstad
- Description: The Cretaceous (133Ma) Kroonstad Group II Kimberlite Cluster is located approximately 200km south west of Johannesburg on the Kaapvaal Craton. The cluster is made up of six kimberlite pipes and numerous other intrusive dike/sill bodies. Three of the pipes are analysed in this study, which includes the: Voorspoed, Lace (Crown) and Besterskraal North pipes. These pipes were emplaced at surface into the Karoo Supergroup, which is comprised of older sedimentary rocks (300-185Ma) overlain by flood basalts (185Ma). At depth the pipes have intruded the Transvaal (2100-2600Ma) and Ventersdorp (2700Ma) Supergroups, which are comprised dominantly of carbonates and various volcanic units respectively. The pipes have typical morphology of South African pipes with circular to sub-circular plan views and steep 82o pipe margins. The Voorspoed pipe is 12ha in size and is characterised by the presence of a large block of Karoo basalt approximately 6ha in size at the current land surface. This large basalt block extends to a maximum of 300m below the current land surface. The main Lace pipe is 2ha is size with a smaller (<0.5ha) satellite pipe approximately 50m to the west. No information is available on the morphology of the Besterskraal North pipe as it is sub-economic and no mining has occurred. Samples from the Besterskraal North pipe were collected from the De Beers archives. The Kroonstad Cluster has been subjected to approximately 1750m of erosion post-emplacement, which has been calculated by the analysis of the crustal xenoliths with the pipe infill. The hypabyssal kimberlite from the three pipes shows a gradational evolution in magma compositions, indicated by the mineralogy and geochemistry. The Lace pipe is the least evolved and has characteristics more similar to Group I kimberlites. The Voorspoed and Besterskraal North kimberlite are intermediately and highly evolved respectively. The gradational evolution is marked by an increase in SiO2 and Na2O contents. Furthermore the occurrence of abundant primary diopside, aegirine, sanidine, K-richterite and leucite indicates evolution of the magma. The root zones of the pipes are characterised by globular segregationary transitional kimberlite, which is interpreted to be hypabyssal and not the result of pyroclastic welding/agglutination. The hypabyssal transitional kimberlite (HKt) is characterised by incipient globular segregationary textures only and the typical tuffisitic transitional kimberlite (TKt) end member (Hetman et al. 2004) is not observed. The HKt contact with the overlying volcaniclastic kimberlite (VK) infill is sharp and not gradational. The presence of HKt in the satellite blind pipe at Lace further indicates that the distinct kimberlite rock type must be forming sub-volcanically. The HKt is distinctly different at the Voorspoed and Lace pipes, which is likely a result of differing compositions of the late stage magmatic liquid. Microlitic clinopyroxene is only observed at the Lace HKt and is interpreted to form as a result of both crustal xenolith contamination and CO2 degassing. Furthermore the HKt is intimately associated with contact breccias in the sidewall. The root zones of the Kroonstad pipes are interpreted to form through the development of a sub-volcanic embryonic pipe. The volcaniclastic kimberlite (VK) infill of the Kroonstad pipes is not typical of South African tuffisitic Class 1 kimberlite pipes. The VK at Voorspoed is characterised by numerous horizontally layered massive volcaniclastic kimberlite (MVK) units, which are interpreted to have formed in a deep open vent through primary pyroclastic deposition. MVK is the dominant rock type infilling the Voorspoed pipe, however numerous other minor units occur. Normally graded units are interpreted to form through gravitational collapse of the tuff ring. MVK units rich in Karoo basalt and/or Karoo sandstone are interpreted to form through gravitational sidewall failure deep within an open vent. Magmaclasts are interpreted to form in the HKt during the development of an embryonic pipe and therefore the term autolith or nucleated autolith may be applied. Debate on the validity of the term nucleated autolith is beyond this study and therefore the term nucleated magmaclast is used to refer to spherical magmaclasts in the VK. The emplacement of the Kroonstad pipes is particularly complex and is not similar to typical Class 1 tuffisitic kimberlites. However the initial stage of pipe emplacement is similar to typical South African kimberlites and is interpreted to be through the development of an embryonic pipe as described by Clement (1982). The vent clearing eruption is interpreted to be from the bottom up through the exsolution of juvenile volatiles and the pipe shape is controlled by the depth of the eruption (+/-2km) (Skinner, 2008). The initial embryonic pipe development and explosive eruption is similar to other South African kimberlites, however the vent is cleared and left open, which is typical of Class 2 Prairies type and Class 3 Lac de Gras type pipes. The latter vent infilling processes are similar to Class 3 kimberlites from Lac de Gras and are dominated at the current level by primary pyroclastic deposition.
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Goat production in the Northern Cape: what are the impacts of farmer training?
- Authors: Burgess, Roberta
- Date: 2010
- Subjects: Northern Cape (South Africa) Animal culture -- South Africa -- Northern Cape -- Management Animal culture -- Economic aspects -- South Africa -- Northern Cape Goat farmers -- South Africa -- Northern Cape -- Education
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:747 , http://hdl.handle.net/10962/d1003868
- Description: The main millennium development goal is to eradicate extreme poverty and hunger in the world by 2015. South Africa is one of the countries that signed this pledge at the millennium summit in 2000. The Department of Agriculture, has initiated a number of projects to assist farmers and communities with reaching this goal. In the Northern Cape, the commercialization of goats is one such anchor project. The major activities of this project is to train farmers in applied and appropriate production practices, assist them with accessing markets and supporting them with improved livestock. The main aim of this research was to evaluate whether the project has achieved its outcome and whether this outcome, is having an impact on the livelihoods of the farmers involved in the project. After reviewing the literature on evaluation research and programme evaluation across time, the different paradigms and approaches, participatory methodology was used in this study. A case study approach was applied to evaluate the outcomes and effects of the training received by farmers, as part of the commercialization of goats programme. The results of the study proved that the training received by members of the Campbell Agricultural Co-operative Enterprises, changed their goat production practices. The training also had a secondary impact. Trained farmers were imparting (technology transfer) their acquired knowledge to other members of the co-operative. This appeared very effective as all members of the cooperative were farming more scientifically. These changes to the production practices had a positive impact on the livelihoods of the farmers, as their animals were of a better quality and they were able to sell their animals at different markets and for better prices. This has however not commercialized their farming operations as they are still faced with many challenges. These challenges are the lack of a proper marketing structure, access to financial assistance, proper infrastructure and adequate transport for the animals to mention a few. If the Department of Agriculture and Land Affairs is serious about assisting these farmers to move from the status of “emerging farmer” to “commercial farmer” they will have to look at addressing the problems experienced with financial access and access to adequate and appropriate transport.
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Hippocampus: seahorse; brain-structure; spatial map; concept
- Authors: Armstrong, Beth Diane
- Date: 2010
- Subjects: Hippocampus (Brain) Sea horses -- Symbolic representation Meaning (Philosophy) Deleuze, Gilles, 1925-1995 Escher, M C (Maurits Cornelis), 1898-1972 Visual perception Space perception Optical art Art -- Themes, motives
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2427 , http://hdl.handle.net/10962/d1002224
- Description: Through an exploration of both sculptural and thought processes undertaken in making my Masters exhibition, ‘Hippocampus’, I unpack some possibilities, instabilities, and limitations inherent in representation and visual perception. This thesis explores the Hippocampus as image (seahorse) and concept (brain-structure involved in cognitive mapping of space). Looking at Gilles Deleuze’s writings on representation, I will expand on the notion of the map as being that which does not define and fix a structure or meaning, but rather is open, extendable and experimental. I explore the becoming, rather than the being, of image and concept. The emphasis here is on process, non-representation, and fluidity of meaning. This is supportive of my personal affirmation of the practice and process of art-making as research. I will refer to the graphic prints of Maurits Cornelis Escher as a means to elucidate a visual contextualization of my practical work, particularly with regard to the play with two- and three-dimensional space perception. Through precisely calculated ‘experiments’ that show up the partiality of our visual perception of space, Escher alludes to things that either cannot actually exist as spatial objects or do exist, but resist representation. Similarly I will explore how my own sculptures, although existing in space resist a fixed representation and suggest ideas of other spaces, non-spaces; an in-between space that does not pin itself down and become fixed to any particular image, idea, objector representation.
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Historical biogeography of the tribe Platypleurini Schmidt, 1918 (Hemiptera: Cicadidae) with a focus on Southern Africa
- Authors: Price, Benjamin Wills
- Date: 2010
- Subjects: Biogeography -- History -- Africa, Southern Cicadas -- Africa, Southern Cicada (Genus) -- Africa, Southern Biodiversity -- Africa, Southern Cicadas -- Variation -- Africa, Southern
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5708 , http://hdl.handle.net/10962/d1005394
- Description: With our contemporary biota under increasing threat of extinction, it is of interest to understand where, why and how biological diversity is generated. If focussed on appropriate taxa, phylogeographic and phylogenetic studies can assist in the identification of both places and processes central to the origin and maintenance of biological diversity. It is explained why southern Africa presents a perfect test-bed for exploring such mechanisms of diversification and why cicadas (Hemiptera: Cicadidae) have proved very suitable tools for studies of historical biogeography. This study then exemplifies these points by providing the first large-scale investigation of the historical biogeography of the tribe Platypleurini Schmidt, 1918, with emphasis on the genus Platypleura Amyot & Seville, 1843 in southern Africa. Standard methods of DNA sequencing provided data from portions of the mitochondrial small subunit ribosomal 16S RNA (16S) and cytochrome oxidase subunits I (COI) and II (COII); and the nuclear elongation factor 1 alpha (EF-1α) from 400 ethanol-preserved specimens. These data were analysed using standard phylogenetic methods and a time scale of diversification was estimated using a Bayesian framework and both fossil data and DNA substitution rates. The results showed that the tribe is too recent to be of Gondwanan origin. The lack of monophyly of the genera represented in both Asia and Africa showed that the tribe needs formal taxonomic revision. Diversification of the African platypleurine genera coincides with aridification in the early Oligocene. Dispersal of Asian platypleurine taxa coincides with the meeting of Africa and Eurasia in the mid-Oligocene. Two radiations within African Platypleura are hypothesised; one distributed over most of sub-Saharan Africa and the second restricted to southern Africa, with clades restricted within regional biomes. Within each of the three focal biomes, cryptic taxonomic diversity was confirmed, suggesting that, even in relatively well understood groups such as the southern African platypleurine cicadas, molecular data can identify further diversity. Although each focal taxon was restricted to non-overlapping biomes, comparison of the three biomes highlighted interactions between palaeoclimates and fixed landscape features (coastal topography, river catchments and escarpments) as causative agents of vicariance, dispersal, extinction and diversification of these volant insects. The results of using co-distributed species for comparative study cautions against making inferences based on single-taxon datasets and highlights the need to use many, evolutionarily independent taxa when identifying mechanisms of diversification. The dating analyses imply that within-species lineage diversification occurred overwhelmingly within the Pleistocene, a trend that is being increasingly recognised in print for other biota. Some caveats about using phylogenetic approaches to estimate ancestral areas are illustrated. Several recommendations are made regarding additional taxa and data sources for understanding the origin and maintenance of biological diversity.
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Humour's critical capacity in the context of South African dance, with two related analyses
- Authors: Elliott, Nicola
- Date: 2010
- Subjects: Dance -- South Africa Choreography -- South Africa Dance criticism -- South Africa Theater -- South Africa South African wit and humor
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2137 , http://hdl.handle.net/10962/d1002369
- Description: This thesis spans two fields - South African dance and the philosophy of humour - and attempts to link them through an understanding of their formal mechanisms. I attempt to establish two main ideas: that there is a need for a critical praxis in South African dance, and that humour in dance can be part of this process. In Chapter One, I discuss elements of the South African dance and theatre industries pre- and post-1994 towards arguing my first point (that South African dance would benefit from a critical praxis). I probe some of the challenges facing artists and describe howchoreographers are dealing thematically and stylistically (but not formally) with the concept of the 'New' South Africa. Through an investigation of concerns voiced by critics regarding choreographic form in the country, I argue that South African dance would benefit from critical formal investigations in dance-making. Finally, I discuss traditional views of humour in South African dance/theatre and in philosophy, which suggest that humour is predominantly seen as frivolous and unworthy of serious attenfion. In Chapter Two, I offer a defence for humour's more profound critical aspects, suggesting that humour can in fact be seen as critical 'thinking in action'. A discussion of theories about humour reveals that the basis for humour is the incongruous. A subsequent discussion of form in theatre and dance shows how the incongruous might work within dance form to create meta-dance. In this way, I attempt to link the two fields of humour and South African dance and to make the connection between the critical capaci~ies of meta-dance and those of humour. I suggest, in other words, that humour in dance can create a critical awareness, of the likes advocated in Chapter One. In Chapter Three, I discuss aspects of two works: my own This part should be uncomfortable (2008) and Nelisiwe Xaba's Plasticization (2004). The two analyses differ from each other as does the humour in both works. Despite the differences, I argue that humour in both works is operating on a critical level that includes a meta-level of signification.
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Impact of new media technologies on the production of economics news in South Africa : a case study of Fin24.com (www.fin24.com)
- Authors: Phakathi, Bekezela
- Date: 2010
- Subjects: Mass media -- Technological innovations -- South Africa -- Case studies Mass media and technology -- South Africa -- Case studies Journalism, Commercial -- South Africa -- Case studies Online journalism -- South Africa -- Case studies Digital media -- South Africa -- Case studies Communication and technology -- South Africa -- Case studies Social networks -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3510 , http://hdl.handle.net/10962/d1007631
- Description: New media technology continues to provide journalists with sophisticated tools that are changing news processing and gathering. Economics journalists in particular have grasped the possibilities offered by new media technologies. Thus, this paper offers a theoretical and practical look at how new media technologies have impacted the production and processing of economics news in South Africa, with a particular focus on Fin24.com which is South Africa's biggest online economics news publication. Using qualitative research methods and the case-study approach, this thesis documents the impact of new media technologies on the production of economics news. It draws on Witschge and Nygren's (2009) framework which describes how new media technologies change the nature in which news is produced and processed. New media technologies in this study will refer to the Internet, particularly search engines like Google, social networking sites such as Twitter and Facebook, Blogs as well as mobile telephony. Economics journalism will here refer to all coverage of economics and business-related news. This is because the case study (Fin24.com) covers both business and economics journalism by strict definition. Findings reveal that these new media technologies have not only changed economics newsgathering and processing but also journalistic routines. The findings generally show that new media technologies make it easier for economics journalists to produce the news quickly and efficiently. Indeed, the most distinguishing characteristic of new media is its overall speed, which is both challenging and attractive. The findings also reveal that new media technologies within a newsroom can be problematic in a number of ways, mainly raising issues of accuracy and credibility thus challenging the profession of economics journalism more than ever.
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Improving explanation writing skills of junior secondary learners in life sciences: a case study
- Authors: Josua, Helena Megameno N
- Date: 2010
- Subjects: Writing skills English language -- Study and teaching (Secondary) -- South Africa English language -- Writing -- Study and teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1570 , http://hdl.handle.net/10962/d1003452
- Description: Learners in the Junior Secondary Phase (Grades 8 to 10) are often required to answer open-ended questions which require a response in the form of an explanation. As frequently reported in the external examiners' reports of Life Sciences, learners do not write adequate explanations as responses to explanatory questions. This thesis reports on action research based on my experience as a Life Sciences teacher trying to address this problem. Therefore, the purpose of this study was to develop suitable, manageable and effective strategies that I could implement in order to improve my teaching of explanation writing skills of in the Junior Secondary school learners with a view to enhance curriculum content knowledge in Life Sciences. The intervention was carried out in a Grade 10 Life Sciences class which consisted of 35 learners. The first cycle consisted of seven lessons carried out over two weeks in normal school time. The main sources of data from my lesson interventions were the learners' written work, their journal entries, the researcher's journal, the field notes from the non-participant observer and interviews with two focus groups. Both the interviews and the lessons were recorded and transcribed. The research data reveals that the ability of the Junior Secondary learners to write explanations was hindered by language problems. In addition, a lack of integration of language issues into the subject content was a contributing factor to their inadequate writing skills. Spelling errors and lack of expression in English second language contribute to the problem of writing good explanations. The data has also revealed that learners‟ writing skills can be improved by implementing suitable teaching strategies, such as the curriculum cycle as proposed by Gibbons (2002). The curriculum cycle can be modified to fit the learners' needs and the real teaching situation. The amount of practice required to master the skill of writing in the genre of explanations should be considered.
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Indigenous technology and culture in the technology curriculum : starting the conversation : a case study
- Authors: Vandeleur, Sonja
- Date: 2010
- Subjects: Curriculum evaluation -- South Africa Curriculum planning -- South Africa Education -- Curricula -- South Africa Technology -- Study and teaching -- South Africa Indigenous peoples -- Education -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1573 , http://hdl.handle.net/10962/d1003455
- Description: Since the collapse of apartheid and the first democratic elections of 1994, education in South Africa has undergone fundamental transformation and part of this transformation was the reconstruction of the school curriculum. The new curriculum, known as Curriculum 2005 and developed in 1997, introduced Technology as a new learning area. This study is based on the inclusion of ‘indigenous technology and culture’, a new aspect introduced in a revision of Curriculum 2005. The broad goal of the study was to examine and explore pedagogic practice in relation to the inclusion of ‘indigenous technology and culture’ in the revised National Curriculum Statement for Technology. The study was informed by an examination of literature pertaining to philosophy of technology, indigenous knowledge systems and technology education. The review of the literature highlighted the contested nature of ‘indigenous knowledge systems’. Philosophies on the nature of technological knowledge were reviewed in order to explore the meaning of ‘technology’, and a comparative review of curriculum reform in regard to technology education in various parts of the world was conducted. This study presented an attempt to determine the rationale for the inclusion of ‘indigenous technology and culture’ in the revised National Curriculum Statement for Technology in South Africa and to explore and examine what teachers’ existing practices were in this regard. It also examined a process of participatory co-engagement with a focus group of teachers. This process was an attempt to implement ‘indigenous technology and culture’ of the curriculum in a more meaningful way. A case study approach using an in-depth, interpretive design was used. A questionnaire, document analysis, interviews and focus group discussions were used to conduct the investigation. What emerged from the data analysis was that there was unanimous support for the inclusion of ‘indigenous technology and culture’ in the technology curriculum, but implementation had been problematic. This was partly due to difficulties with the interpretation of this aspect in the curriculum as well as a lack of meaningful teaching and learning for various reasons. The study revealed that teachers face multiple dilemmas in implementing ‘indigenous technology and culture’ as an assessment standard. These dilemmas are pedagogical, political, conceptual, professional and cultural in nature. The intentions of the study were to build a comprehensive understanding of ‘indigenous technology and culture’ and to determine how a focus group of teachers were dealing with this new inclusion. The interpretive study concluded with implications and recommendations for further studies.
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Induced plant responses of different Lantana camara L. (Verbenaceae) varieties to herbivory by Falconia intermedia (distant) (Hemiptera: Miridae)
- Authors: Heshula, Unathi-Nkosi Lelethu Peter
- Date: 2010
- Subjects: Lantana camara -- South Africa -- Eastern Cape , Lantana camara -- Biological control -- South Africa -- Eastern Cape , Biological pest control agents -- South Africa -- Eastern Cape , Weeds -- Biological control -- South Africa -- Eastern Cape , Invasive plants -- Biological control -- South Africa -- Eastern Cape , Hemiptera -- South Africa -- Eastern Cape , Miridae -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5911 , http://hdl.handle.net/10962/d1015368
- Description: A highly variable invasive shrub, Lantana camara L. (Verbenaceae), has been notoriously difficult to control thus far despite a well established biological control programme in South Africa. A promising leaf-feeding biological control agent, Falconia intermedia (Distant) (Hemiptera: Miridae), released to control this invasive plant eventually crashed at three out of five sites in the Eastern Cape Province. In the Mpumalanga Province, after initially colonising and building up high numbers on the L. camara stands the agent populations crashed. Several reasons for these population crashes have been suggested, but induced plant defences have not been investigated. Although plants face the challenge of herbivory by various organisms while remaining immobile, some plants may possess the ability to induce physical and/or chemical defensive responses following feeding and thus prevent further plant tissue damage and loss. Laboratory trials were conducted to determine the existence, nature and effect of physical and chemical feeding-induced responses of L. camara on the performance of the leaf-feeding biological control agent, F. intermedia. Lantana camara plants used in the study were obtained from five localities in the Eastern Cape Province, South Africa, while the insect culture was established from field populations. Plants from all varieties on which F. intermedia was released significantly increased the toughness of their leaves compared to control treatment plants. In addition, plants from three localities: Lyndhurst Farm, East London and Port Alfred, significantly increased trichome density after prolonged feeding by F. intermedia. On the three varieties showing increases in these two factors (i.e. leaf toughness and trichome density), oviposition, survival and feeding damage by the mirid agent was significantly lower on previously damaged plants. A significant negative correlation between trichome density and population numbers was found (R²= 0.52, p < 0.0003), suggesting that an increase in trichome density strongly contributes to a reduction in F. intermedia's growth. The growth and reproduction of the resistant plants was not significantly impacted by F. intermedia feeding. The defensive responses were found to be plant systemic and rapidly induced as they were elicited and expressed throughout the plant in both damaged and undamaged leaves within five weeks after insect release. Leaf toughness and trichome density were not significantly increased after feeding on plants from Whitney Farm and Heather Glen Farm. On the contrary, mirid individuals performed significantly better on plants from Whitney Farm and Heather Glen Farm than on plants of other varieties, indicating their susceptibility and suitability to the agent and the lack of induced resistance against the agent. Plants from all localities besides East London showed some level of tolerance and overcompensated for feeding damage by increasing plant growth and reproductive factors on plants fed upon. This was however only significant in two variables of the more susceptible localities, Whitney Farm and Heather Glen Farm. This increase in plant fitness did however indicate an induced defence response by these plants to feeding, a response designed to lessen the effects of agent feeding. Headspace volatile analysis was used to investigate any volatile chemical responses by L. camara due to F. intermedia feeding at two of the five localities chosen: East London and Whitney Farm. There was no significant difference in headspace volatiles emitted by leaves of plants from the East London insect infested and control treatment plants. On the Whitney Farm damaged plants however there was a 2.5 fold increase in the emission intensity of one of the three main compounds, later identified as Beta-caryophyllene. Three major chemical constituents which were found to be common to leaf volatiles of the two varieties were identified through gas chromatography-mass spectrometry (GC-MS) from the damaged and undamaged leaves of these two varieties. The methods used in collecting leaf volatiles were shown to be significant in the strength of chromatogram peaks. Using general authentication methods and purified standards, one of these was identified as the sesquiterpene, Beta-caryophyllene (C₁₅H₂₄). This compound is one of the major constituents found in isolations of L. camara varieties worldwide. This is the first such work done on a variety of L. camara in South Africa, and hopefully the beginning of more in-depth studies of the volatile organic chemicals from the numerous naturalised varieties of L. camara. It is suggested that the sum of these responses may play a role bigger than is currently understood in this plant-insect relationship. It is also argued that feeding induced plant defences may play an important role in attempts to control alien plants using insect agents.
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Informing an ICT intervention for HIV and AIDS education at Rhodes University
- Authors: Gunzo, Fortunate Takawira
- Date: 2010
- Subjects: AIDS (Disease) -- Prevention -- South Africa AIDS (Disease) -- Study and teaching -- South Africa HIV infections -- Prevention -- South Africa HIV infections -- Study and teaching -- South Africa Health education -- South Africa Educational technology -- South Africa Rhodes University -- Students -- Attitudes Counseling in higher education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1577 , http://hdl.handle.net/10962/d1003459
- Description: This study captures the process and methods used in selecting and organising content for an ontology. In the Information and Communication Technology (ICT) field ontology refers to a way of organising and storing information and facilitating interaction between the system and its users. Ontologies are being used more frequently to provide services that deal with complex information. In this study, I record my experience of developing content for an HIV and AIDS ontology for Rhodes University students. Using several different methods, I started the process of selecting and organising HIV and AIDS information, free of scientific jargon and prescriptive language, and consisting only of relevant information. I used data derived from interviews with six HIV and AIDS experts to develop questions for a survey that was open to all Rhodes University students. The 689 people who responded to the survey indicated that they needed more information on testing, treatment and living with HIV. Responses also showed that students had a lot of information on HIV prevention and transmission. Four focus group discussions revealed that students were tired of repetitions of the „same‟ information on HIV and AIDS and wanted to know more about life after contracting HIV. Using this data, I propose some guidelines to populate HIV and AIDS ontology. Ontologies can be customized for particular groups of users, for example according to gender, race, year of study etc. Another advantage of the ontology is that it can be expanded or contracted depending on the scope of one‟s intervention.
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Intertidal patterns and processes : tracking the effects of coastline topography and settlement choice across life stages of the mussels perna perna and mytilus galloprovincialis
- Authors: Von der Meden, Charles Eric Otto
- Date: 2010
- Subjects: Mexilhao mussel -- Behavior -- South Africa Mytilus galloprovincialis -- Behavior -- South Africa Perna -- Behavior -- South Africa Mussels -- Ecology -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5721 , http://hdl.handle.net/10962/d1005407
- Description: Within landscapes, spatial heterogeneity is common and specific landscape features can influence propagule dispersal by wind or water, affecting population connectivity and dynamics. Coastline topographic features, such as bays and headlands, have a variety of biophysical effects on nearshore oceanography, larval transport, retention and supply, and the processes of larval settlement and recruitment. Although this has been demonstrated in several parts of the world, engendering a perception of a general ‘bay effect’, few studies have investigated this generality in a single experiment or region, by replicating at the level of ‘bay’. The Agulhas biogeographic region of the south coast of South Africa is a useful system within which to test for such generality. Using the intertidal mussels Mytilus galloprovincialis and Perna perna as model organisms, patterns of adult distribution were surveyed across four large ‘halfheart’ bays and intervening stretches of open coast, providing replication at the level of ‘bay’ and duplication of ecologically similar species. In support of a general, pervasive influence of bays on intertidal populations, mussel cover was found to be greater in bays than on the open coast for both species, although the effect was strongest for M. galloprovincialis. To explain this adult distribution, settlement, post-settlement mortality and recruitment were examined over 12mo at the same sites, with the prediction that rates of each would favour larger bay populations. Contrary to this, an interaction between month and bay-status was found, with greater settlement and recruitment on the open coast than in bays reflecting extreme settlement and recruitment events at 3 westerly open coast sites during summer. Re-analysis excluding these outliers, revealed the expected effect, of greater settlement and recruitment in bays. While this indicates the broad generality of the bay effect, it highlights exceptions and the need for replication in time and space when examining landscape effects. Measuring post-settlement mortality required testing small-scale settlement behaviour on established and newly deployed settler collectors. It was found that all settlers preferred collectors with biofilm, but that primary settlers avoided conspecific settlers, while secondary settlers were attracted to them. With discrepancies in settler attraction to new and established collectors accounted for, initial (over 2d) and longer-term (over 7d) post-settlement mortality rates were found to be substantial (ca 60 %) for both species. No topographic effect on p-s mortality was evident. Finally, recruit-settler, adult-recruit and interspecies correlations were examined at regional and local scales. Synergistic (or neutral) effects maintained the initial settlement pattern in recruit and adult populations regionally, but not at local scales; striking interspecies correlations suggested the influence of common regional transport processes. Ultimately, the results emphasize the importance of the direction of effects in different life stages and at different spatial scales, and the possibility that antagonistic effects may mask even strong patterns.
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Investigation of entomopathogenic fungi for control of false codling moth, Thaumatotibia leucotrata, Mediterranean fruit fly, Ceratitis capitata and Natal fruit fly, C. rosa in South African citrus
- Authors: Goble, Tarryn Anne
- Date: 2010
- Subjects: Insect pests -- Biological control , Tortricidae -- Biological control -- South Africa , Tephritidae -- Biological control -- South Africa , Citrus -- Diseases and pests -- Biological control -- South Africa , Entomopathogenic fungi , Fungi as biological pest control agents , Biological pest control agents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5723 , http://hdl.handle.net/10962/d1005409 , Insect pests -- Biological control , Tortricidae -- Biological control -- South Africa , Tephritidae -- Biological control -- South Africa , Citrus -- Diseases and pests -- Biological control -- South Africa , Entomopathogenic fungi , Fungi as biological pest control agents , Biological pest control agents
- Description: The biology of key citrus pests Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae), Ceratitis capitata Wiedemann (Diptera: Tephritidae) and Ceratitis rosa Karsch (Diptera: Tephritidae) includes their dropping from host plants to pupate in the soil below citrus trees. Since most EP fungi are soil-borne microorganisms, the development and formulation of alternative control strategies using these fungi as subterranean control agents, targeted at larvae and pupae in the soil, can potentially benefit existing IPM management of citrus in South Africa. Thus, a survey of occurrence of entomopathogenic fungi was undertaken on soils from citrus orchards and natural vegetation (refugia) on conventionally and organically managed farms in the Eastern Cape Province in South Africa. A method for baiting soil samples with citrus pest T. leucotreta and C. capitata larvae, as well as with the standard bait insect, Galleria mellonella Linnaeus (Lepidoptera: Pyralidae), was implemented. Sixty-two potentially useful entomopathogenic fungal isolates belonging to four genera were collected from 288 soil samples, an occurrence frequency of 21.53%. The most frequently isolated entomopathogenic fungal species was Beauveria bassiana (Balsamo) Vuillemin (15.63%), followed by Metarhizium anisopliae var. anisopliae (Metschnikoff) Sorokin (3.82%). Galleria mellonella was the most effective insect used to isolate fungal species (χ2=40.13, df=2, P≤ 0.005), with a total of 45 isolates obtained, followed by C. capitata with 11 isolates, and T. leucotreta with six isolates recovered. There was a significantly (χ2=11.65, df=1, P≤ 0.005) higher occurrence of entomopathogenic fungi in soil samples taken from refugia compared to cultivated orchards of both organically and conventionally managed farms. No significant differences were observed in the recovery of fungal isolates when soil samples from both farming systems were compared. The physiological effects and host range of 21 indigenous fungal isolates obtained in the Eastern Cape were investigated in the laboratory to establish whether these isolates could be effectively used as biological control agents against the subterranean life stages of C. rosa, C. capitata and T. leucotreta. When these pests were treated with a fungal concentration of 1 x 10⁷ conidia ml⁻¹, the percentage of T. leucotreta adults which emerged in fungal treated sand ranged from 5 to 60% (F=33.295; df=21; P=0.0001) depending on fungal isolate and the percentage of pupae with visible signs of mycosis ranged from 21 to 93% (F= 96.436; df=21; P=0.0001). Based on fungal isolates, the percentage adult survival in C. rosa and C. capitata ranged from 30 to 90% and 55 to 86% respectively. The percentage of C. rosa and C. capitata puparia with visible signs of mycosis ranged from 1 to 14% and 1 to 11% respectively. Deferred mortality due to mycosis in C. rosa and C. capitata adult flies ranged from 1 to 58% and 1 to 33% respectively, depending on fungal isolate. Entomopathogenic fungal isolates had a significantly greater effect on the adults of C. rosa and C. capitata than they did on the puparia of these two fruit fly species. Further, C. rosa and C. capitata did not differ significantly in their response to entomopathogenic fungi when adult survival or adult and pupal mycosis were considered. The relative potency of the four most virulent Beauveria isolates as well as the commercially available Beauveria bassiana product, Bb Plus® (Biological Control Products, South Africa), were compared against one another as log-probit regressions of mortality against C. rosa, C. capitata and T. leucotreta which all exhibited a dose-dependent response. Against fruit flies the estimated LC50 values of all five Beauveria isolates ranged from 5.5 x 10¹¹ to 2.8 x 10¹² conidia/ml⁻¹. There were no significant differences between the relative potencies of these five fungal isolates. When T. leucotreta was considered, isolates: G Moss R10 and G 14 2 B5 and Bb Plus® were significantly more pathogenic than G B Ar 23 B3 and FCM 10 13 L1. The estimated LC₅₀ values of the three most pathogenic isolates ranged from 6.8 x 10⁵ to 2.1 x 10⁶ conidia/ml⁻¹, while those of the least pathogenic ranged from 1.6 x 10⁷ to 3.7 x 10⁷ conidia/ml⁻¹. Thaumatotibia leucotreta final instar larvae were exposed to two conidial concentrations, at four different exposure times (12, 48, 72 and 96 hrs) and showed an exposure time-dependant relationship (F=5.43; df=3; P=0.001). At 1 x 10⁷conidia/ml⁻¹ two Beauveria isolates: G Moss R10 and G 14 2 B5 were able to elicit a response in 50% of test insects at 72 hrs (3 days) exposure. Although a limited amount of mycosis was observed in the puparia of both fruit fly species, deferred adult mortality due to mycosis was high. The increased incidence of adult mortality suggests that post emergence mycosis in adult fruit flies may play a more significant role in field suppression than the control of fruit flies at the pupal stage. The increased incidence of pupal mortality, as well as the relatively low concentrations of conidia required to elicit meaningful responses in T. leucotreta pupae may suggest that pre-emergent control of false codling moth will play a more significant role in field suppression than the control of adult life stages using indigenous isolates of entomopathogenic fungi. Various entomopathogenic fungal application techniques targeted at key insect pests within integrated pest management (IPM) systems of citrus are discussed.
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Investigations of the bioavailability/bioequivalence of topical corticosteroid formulations containing clobetasol propionate using the human skin blanching assay, tape stripping and microdialysis
- Authors: Au, Wai Ling
- Date: 2010
- Subjects: Adrenocortical hormones -- Bioavailability , Drugs -- Therapeutic equivalency , Adrenocortical hormones -- Effectiveness , Adrenocortical hormones -- Testing , Adrenocortical hormones -- Side effects , Transdermal medication
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3743 , http://hdl.handle.net/10962/d1003221 , Adrenocortical hormones -- Bioavailability , Drugs -- Therapeutic equivalency , Adrenocortical hormones -- Effectiveness , Adrenocortical hormones -- Testing , Adrenocortical hormones -- Side effects , Transdermal medication
- Description: Currently, clinical trials in patients are required by most regulatory authorities for the assessment of bioequivalence of topical products where the drug is not intended for systemic absorption. Hence there is a dire need for suitable methods for the assessment of bioavailability and bioequivalence of such products since clinical safety and efficacy studies are expensive, time-consuming and require very large numbers of patients. Except for topical corticosteroid products where the human skin blanching assay/vasoconstrictor assay has been approved by the US FDA for bioequivalence assessment of those products, no other method has been “officially” approved for use in those investigations. However, a few alternative methods such as tape stripping and microdialysis have been pursued and considered to have the potential for use in ioequivalence/bioavailability studies. The human skin blanching assay was used to assess the bioequivalence of commercially available topical products containing 0.05% clobetasol propionate. Both visual and chromameter data were obtained and a commercially available topical corticosteroid product, Dermovate® cream was used as both the “Test” and the “Reference” product. The results indicated that both visual and chromametric assessments were comparable to each other and that either could be used for the assessment of the bioequivalence of topical products containing clobetasol propionate. The screening procedure was optimized to identify potential “detectors” for inclusion in the bioequivalence studies. This resulted in fewer subjects being required in a bioequivalence pivotal study, still having the necessary power to confirm bioequivalence using the human skin blanching assay. Another objective of this research was to re-visit tape stripping and other possible alternative methods such as dermal microdialysis and to optimize these procedures for bioequivalence assessment of topical formulations where the drug is not intended for systemic absorption. In the past few decades, tape stripping has been used to investigate bioavailability/bioequivalence of various topical formulations. This technique involves the removal of the stratum corneum to assess drug penetration through the skin. A draft FDA guidance for tape stripping was initially published but was subsequently withdrawn due to high variability and poor reproducibility. This research project used an optimized tape stripping procedure to determine bioavailability and establish bioequivalence between three commercially available formulations containing 0.05 % m/m clobetasol propionate. Furthermore, tape stripping was validated by undertaking a study to assess the bioequivalence of a 0.05% topical cream formulation (Dermovate® cream) using the same cream as both the “Test” and “Reference” product, in which bioequivalence was confirmed. The findings highlight the potential of tape stripping as an alternative method for the assessment of bioequivalence of clobetasol propionate formulations and may possibly be extended for use in other topical products. Microdialysis is another useful technique that can assess the penetration of topically applied substances which diffuses through the stratum corneum and into the dermis. Microdialysis has previously been successfully used for in vivo bioavailability and bioequivalence assessments of topical formulations. However, the drugs which were under investigation were all hydrophilic in nature. A major problem with the use of microdialysis for the assessment of lipophilic substances is the binding/adherence of the substance to the membrane and other components of the microdialysis system. As a result, this necessitates the development of a microdialysis system which can be used to assess lipophilic drugs. Intralipid® 20% was investigated and successfully utilized as a perfusate to recover a lipophilic topical corticosteroid, clobetasol propionate, in microdialysis studies. Hence, the bioavailability of clobetasol propionate from an extemporaneous preparation was determined in healthy human volunteers using microdialysis. These findings indicate that in vivo microdialysis can be used to assess lipophilic drug penetration through the skin. A novel approach to investigate drug release from topical formulations containing 0.05% clobetasol propionate using in vitro microdialysis was also undertaken. The in vitro findings were found to be in agreement with the results obtained using tape stripping to assess bioequivalence of the same commercially available products, namely Dermovate® cream, Dovate® Cream and Dermovate® ointment. These results indicate the potential to correlate in vitro with in vivo data for bioequivalence assessment of such topical dosage forms.
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Isolation and evolution of novel nucleoside phosphorylases
- Authors: Visser, Daniel Finsch
- Date: 2010
- Subjects: AIDS (Disease) -- Treatment -- Africa HIV Infections -- Treatment -- Africa AIDS (Disease) -- Patients -- Africa HIV-Positive persons -- Africa Antiretroviral agents Pyrimidine nucleotides
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3972 , http://hdl.handle.net/10962/d1004031
- Description: Approximately 33.4 million people are living with HIV/AIDS. Of those, 97% live in low and middle income countries, with 22.4 million in sub-Saharan Africa. Only 42% of the people who require anti-retrovirals (ARVs) in low to middle income countries are receiving anti-retroviral therapy (ART). There is a need to develop novel and cost effective methods for producing antiretroviral drugs. Stavudine and azidothymidine (AZT) were identified as potential targets because they could both be produced through a common intermediate – 5 methyluridine (5-MU). It has been established that the biocatalytic production of 5-methyluridine is possible through a reaction known as transglycosylation, in a process which has not previously been demonstrated as commercially viable. A selection of biocatalysts were expressed either in recombinant E. coli strains or in the wild type organisms, purified and then screened for their ability to produce 5-MU. A combination of Bacillus halodurans purine nucleoside phosphorylase 1 (BHPNP1) and E. coli uridine phosphorylase (EcUP) gave the highest 5-MU yield (80%). This result represents the first combination of free enzymes from different organisms, giving high yields of 5-MU under high substrate conditions. Both enzymes were purified and successfully characterised. The established pH optimum was pH 7.0 for both enzymes. Temperature optima and stability data for BHPNP1 (70 C and t1/2 at 60 C of 20.8 h) indicated that the biocatalytic step was operating within the capabilities of this enzyme and would operate well at elevated temperatures (up to 60 C). Conversely, the temperature optimum and stability data for EcUP (optimum of 40 C and t1/2 at 60 C of 9.9 h) indicated that the enzyme remained active at 40 C for the duration of a 25 h biotransformation, but at 60 C would only be operating at 20% of its optimum activity and would lose activity rapidly. BHPNP1 and EcUP were used in a bench scale (650 ml) transglycosylation for the production of 5-MU. A 5-MU yield of 79.1% was obtained at this scale with a reactor productivity of 1.37 g.l-1.h-1. Iterative saturation mutagenesis was used to rapidly evolve EcUP for improved thermostability. A moderately high throughput colorimetric method was developed for screening the mutants based on the release of p-nitrophenol upon phosphorolysis of a pyrimidine nucleoside analogue. By screening under 20 000 clones the mutant UPL8 was isolated. The mutant enzyme showed an optimum temperature of 60 C and improved stability at 60 C (t1/2 = 17.3 h). The increase in stability of UPL8 is due to only 2 mutations (Lys235Arg, Gln236Ala). These mutations may have caused an increase in stability due to interactions with other structural units in the protein, stabilization of the entrance to the binding pocket, or by decreasing the flexibility of the α-helix at the N-terminus. Transglycosylation experiments showed that the mutant enzyme UPL8 is a superior catalyst for the production of 5-MU. A 300% increase in reactor productivity was noted when free enzyme preparations of UPL8 was combined with BHPNP1 at 1.5% m.m-1 substrate loading. The high yield of 5-MU (75-80% mol.mol-1) was maintained at 9% m.m-1 substrate loading. A commercially viable productivity of 31 g.l-1.h-1 was thus realised. Further optimisation of the process could produce still higher productivities. Future work in directed evolution of nucleoside phosphorylases is envisaged for improved stability and enhanced substrate range for application to other commercially relevant transglycosylation reactions.
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Isolation of xylanolytic multi-enzyme complexes from Bacillus subtilis SJ01
- Authors: Jones, Sarah Melissa Jane
- Date: 2010
- Subjects: Bacillus subtilis , Xylans , Multienzyme complexes , Botanical chemistry , Cellulose , Hemicellulose , Polysaccharides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3974 , http://hdl.handle.net/10962/d1004033 , Bacillus subtilis , Xylans , Multienzyme complexes , Botanical chemistry , Cellulose , Hemicellulose , Polysaccharides
- Description: Cellulose and hemicellulose account for a large portion of the world‘s plant biomass. In nature, these polysaccharides are intertwined forming complex materials that require multiple enzymes to degrade them. Multi-enzyme complexes (MECs) consist of a number of enzymes working in close proximity and synergistically to degrade complex substrates with higher efficiency than individual enzymes. The cellulosome is a cellulolytic MEC produced by anaerobic bacteria that has been studied extensively since its discovery in 1983. The aim of this study was to purify a cellulolytic and/or hemicellulolytic MEC from an aerobic bacterium of the Bacillus genus. Several bacterial isolates were identified using morphological characteristics and 16S rDNA sequencing, and screened for their ability to degrade cellulose and xylan using a MEC. The isolate that produced a high molecular weight protein fraction with the greatest ability to degrade Avicel®, carboxymethyl cellulose (CMC) and birchwood xylan was identified as Bacillus subtilis SJ01. An optimised growth medium, consisting of vitamins, trace elements, birchwood xylan (as the carbon source), and yeast and ammonium sulphate (as the nitrogen sources), increased the production of CMCase and xylanase enzymes from this bacterium. The removal of a competing bacterial strain from the culture and the inhibition of proteases also increased enzyme activities. A growth curve of B. subtilis SJ01 indicated that xylanase production was highest in early stationary growth phase and thus 84 hours was chosen as the best cell harvesting time. To purify the MECs produced by B. subtilis SJ01 size-exclusion chromatography on a Sephacryl S-400 column was used. It was concluded that (for the purposes of this study) the best method of concentrating the culture supernatant prior to loading onto Sephacryl S-400 was the use of ultrafiltration with a 50 kDa cut-off membrane. Two MECs, named C1 and C2 of 371 and 267 kDa, respectively, were purified from the culture supernatant of B. subtilis SJ01. Electrophoretic analysis revealed that these MECs consisted of 16 and 18 subunits, respectively, 4 of which degraded birchwood xylan and 5 of which degraded oat spelt xylan. The MECs degraded xylan substrates (C1: 0.24 U/mg, C2: 0.14 U/mg birchwood xylan) with higher efficiency than cellulose substrates (C1: 0.002 U/mg, C2: 0.01 U/mg CMC), and could therefore be considered xylanosomes. Interestingly, the MECs did not bind to insoluble birchwood xylan or Avicel® and did not contain glycosylated proteins, which are common features of cellulosomes. This study is, therefore, important in revealing the presence of MECs that differ from the cellulosome and that may have particular application in industries requiring high xylanase activity, such as the paper and pulp industry. The abundant genetic information available on B. subtilis means that this organism could also be used for genetic engineering of cellulolytic/hemicellulolytic MECs.
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Isomorphism, institutional entrepreneurship and total quality management (TQM) : a case study in the implementation of quality management standards and excellence models in South African developmental local government
- Authors: Naidoo, Pravine
- Date: 2010
- Subjects: Local government -- South Africa -- Eastern Cape Political entrepreneurship -- South Africa -- Eastern Cape Total quality management Municipal services -- South Africa -- Eastern Cape -- Management Municipal services -- Customer services -- South Africa -- Eastern Cape Political leadership -- South Africa -- Eastern Cape Organizational effectiveness
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1193 , http://hdl.handle.net/10962/d1007141
- Description: Within the new constitutional order, South African local government has been afforded specific status and is protected as a distinctive sphere of government in terms of the Constitution Act 108 of 1996. Municipalities are no longer a mere function of national or provincial governments. In addition to this entrenched status, the Constitution and other developmental local government legislation vests local government with specific functions and responsibilities as part of the process of building a new democracy and promoting socio-economic development and upliftment. Consequently, local government managers are under constant pressure to improve the performance and quality of service delivery. They are expected to satisfy a number of stakeholders, achieve increases in efficiency, as well as attain developmental service delivery goals as contained in their Integrated Development Plan (IDP). Quality management standards and excellence models in support of the total quality management (TQM) philosophy are relatively new public management approaches that changes traditional organisational decision-making practices to deliver services to its customers in more effective and efficient ways. In essence, quality management standards and excellence models are performance management methodological practices, techniques and tools designed to meet and exceed public requirements. It accomplishes this through determining what constitutes excellence in customer service, and then empowering employees to a never-ending search for quality improvement in the delivery of services, in terms of the continuous improvement and continuous process improvement philosophies, of which total quality management (TQM) is premised on. Consequently, quality management standards and excellence models (such as the ISO 9001: 2008 QMS, ISO 14001: 2004 EMS, EFQM and SAEF Excellence Models) as methodological practices, techniques or tools in support of the critical factors (CFs) of the total quality management (TQM) philosophy, namely: (1) customer-based approach, (2) senior management commitment and leadership, (3) quality planning, (4) management based on facts, (5) continuous improvement, (6) involvement of all members of the organisation, (7) education and training, (8) teamwork, (9) communication systems, (10) learning, (11) process management, (12) co-operation with suppliers, and (13) organisational awareness and concern for the social and environmental context, can provide a framework by which to achieve the goals of effective and efficient service delivery in developmental local government, as they foster a culture of performance and accountability. Local government managers could use these quality and excellence methodological practices, techniques and tools, as a starting point to improve efficiencies in their municipalities, as the programmes afford them an opportunity to systematically evaluate the municipality and determine what leads to organisational success and deliverables. Institutional theory suggests that organisations are both influenced by and can influence the society in which they operate. Institutional theorists believe that the motivation for a change in internal practices might not only be performance related, but may primarily be to enhance or maintain the legitimacy of the respective institution. Institutional theory also focuses on the social contract that exists between the institution and society. This social contract is believed to represent the expectations of society. From an institutional point of view, it has been suggested that institutions may change and adopt the norms of society to appear legitimate to that society. This infers that when societal norms and values change, institutions will be expected to change. These societal pressures combined with legislative changes, require institutional entrepreneurs to respond to these isomorphic pressures, and will work to preserve the institution's legitimacy by incorporating, or at least appearing to incorporate, new practices, norms and values. The aim of this research study was to analyse within an institutional theory framework, the implementation of quality management standards and excellence models in support of the total quality management (TQM) philosophy and developmental local government within two South African municipalities. The research investigation has been undertaken within the social constructionist paradigm and using the case study method. Interviews and documents were the data sources and thematic analysis was used as a tool to analyse the data by applying a theory-driven coding procedure. The findings from the two research sites, namely Makana Municipality in Grahamstown and Drakenstein Municipality in Paarl reveal that the implementation of quality management standards and excellence models in support of the total quality management (TQM) philosophy in both municipalities was not a smooth process and there were many challenges such as political instability, lack of commitment on the part of the senior leadership and management, staff and skills shortages, resistance by staff to implementation and resource constraints. Institutional theory has proved to be useful in understanding why the Makana and Drakenstein Municipalities implemented quality management standards and excellence models. Because of coercive, mimetic and normative isomorphic pressures affecting the Makana and Drakenstein municipalities, change was imperative if these institutions were to remain relevant and legitimate in order to address its service delivery mandate of effectiveness and efficiency. Institutional theory provided a theoretical lens to understand and appreciate the pressures that affected the municipalities because of its new developmental mandate as encapsulated in new municipal legislation. It also assisted in understanding how institutional entrepreneurs responded to these pressures to conform. The implementation of quality management standards and excellence models in the Makana and Drakenstein municipalities was adversely affected by volatility amongst the political leadership of both municipalities. The successful implementation of these standards and models would require collective action from the political, bureaucratic and procedural entrepreneurs in order to enhance effective, efficient and accountable service delivery. However, in both the Makana and Drakenstein municipalities, institutional entrepreneurs, namely councillors and officials were not working together as a collective to implement quality management standards and excellence models. Evidence has shown that the absence of stable political leadership and noncooperation and collaboration amongst institutional entrepreneurs contributed significantly to the non-institutionalisation of quality management standards and excellence models in these Municipalities. This implies that legitimacy has not been achieved, due to institutional entrepreneurs not collaborating and collectively working with each other to implement the quality management standards and excellence models. Thus, this research study suggests that the strategic and collective role of the political and administrative leadership as institutional entrepreneurs is critical if the municipality is to achieve its aims and objectives, namely effective, efficient, and accountable service delivery in developmental local government. Recommendations in respect of future research and to practitioners have also been offered.
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Israel and Palestine: some critical international relations perspectives on the 'two-state' solution
- Authors: Pienaar, Ashwin Mark
- Date: 2010
- Subjects: Arab-Israeli conflict Jewish-Arab relations Nationalism -- Israel Nationalism -- Palestine Land settlement -- West Bank Land settlement -- Gaza Strip Realism Liberalism Palestinian Arabs -- Politics and government -- 20th century Israel -- Politics and government -- 20th century Israel -- Foreign relations -- Palestine Palestine -- Foreign relations -- Israel
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2820 , http://hdl.handle.net/10962/d1003030
- Description: This research questions whether Israel and Palestine should be divided into two states. Viewed through the International Relations (IR) theories of Realism and Liberalism, the ‘Two-State’ solution is the orthodox policy for Israel and Palestine. But Israelis and Palestinians are interspersed and share many of the same resources making it difficult to create two states. So, this research critiques the aforementioned IR theories which underpin the ‘Two-State’ solution. The conclusion reached is that there ought to be new thinking on how to resolve the Israel-Palestine issue.
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Lag length selection for vector error correction models
- Authors: Sharp, Gary David
- Date: 2010
- Subjects: Akaike Information Criterion Mathematical models -- Evaluation Autoregression (Statistics) Error analysis (Mathematics)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5568 , http://hdl.handle.net/10962/d1002808
- Description: This thesis investigates the problem of model identification in a Vector Autoregressive framework. The study reviews the existing research, conducts an extensive simulation based analysis of thirteen information theoretic criterion (IC), one of which is a novel derivation. The simulation exercise considers the evaluation of seven alternative error restricted vector autoregressive models with four different lag lengths. Alternative sample sizes and parameterisations are also evaluated and compared to results in the existing literature. The results of the comparative analysis provide strong support for the efficiency based criterion of Akaike and in particular the selection capability of the novel criterion, referred to as a modified corrected Akaike information criterion, demonstrates useful finite sample properties.
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Language policy and practice at CM Vellem and PJ Olivier primary schools
- Authors: Fobe, Mila Pamella
- Date: 2010
- Subjects: C M Vellem School P J Olivier School Public schools -- South Africa -- Grahamstown Language policy -- South Africa Language and education -- South Africa -- Grahamstown Native language and education -- South Africa -- Grahamstown Afrikaans language -- Study and teaching (Primary) -- South Africa -- Grahamstown Xhosa language -- Study and teaching (Primary) -- South Africa -- Grahamstown English language -- Study and teaching (Primary) -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3586 , http://hdl.handle.net/10962/d1002161
- Description: This study looks at language policy and practice at two Eastern Cape schools. It further explores the link between language learning and teaching. Language implementation strategies were the main focus of this study. The Language-in-education policy of the Republic of South Africa (1997) promotes the use of all nine African languages, which have been afforded the status of official languages. This study looks at the language teaching practices at two Grahamstown primary schools, where isiXhosa and Afrikaans have been used as media of instruction. Qualitative methods were used, and the study took the form of interpretive case studies. , Thuto e, e ikaelela go tshegetsa patlisiso e e ka ga gore dipuo tsa Selegae tsa Seaforika mo Aforikaborwa di tshwanelwa ke go tsewa ka maemo le mokgwa o o lekanang go ya ka Molaotheo wa Aforikaborwa. Ka jalo, e tlaa utolola,e ribilole ditsela le go batla malepa a puso ya Aforikaborwa e ka fitlhelelang setšhaba se se kwa magaeng, se bokgoni jwa kitso ya Seesimane bo leng kwa tlase mo go bona. Bothata ke gore Aforikaborwa e laolwa bogolo ke tiriso e e kwa godimo ya Seesimane mme puso e tshwanelwa ke gore e tlose dikgoreletsi tse di leng teng ga jaana tsa puo. E bowe gape e thibele go se lekalekaneng ga botshelo ka kakaretso mo loagong go go tlholwang ke go sa lekalekaneng ga kitso ya dipuo mo setšhabeng ka kakaretso. Ditshwanelo mo puong fela jaaka ditshwanelo dingwe le dingwe tsa botho, di tshwanelwa ke go sireletswa, jaaka di akareditswe mo Molaotheo o mošwa wa temokerasi wa Aforikaborwa.
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Learning about water through the African catchment game : the refinement of a role playing simulation game
- Authors: Fraenkel, Linda Anne
- Date: 2010
- Subjects: Water -- South Africa -- Management -- Simulation methods Water -- Management -- Study and teaching Rain and rainfall -- South Africa -- Simulation methods Simulation games in education Role playing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:4842 , http://hdl.handle.net/10962/d1005518
- Description: This research has undertaken two key mandates. One was to develop modifications to the African Catchment Game (ACG), a role playing simulation game, in order to simulate rainfall and water management processes representative of the southern African context. The other was to understand what, if any, learning associated with water management issues had taken place as a result of playing the ACG. The modification process took the form of an action research process. The initial modifications were trialed with South African students as part of their undergraduate Geography course offered at Rhodes University, South Africa. Subsequent modifications were implemented over a five month period with three diverse participant groups, namely Finnish, American and South African participants. An interpretive research orientation was employed in order to analyse both the qualitative and quantitative data that was generated. Pre- and Post-Game Questionnaires were used in order to identify the learning and understanding which the participants constructed as a result of playing the ACG. The Chi-Square Test was also applied to each of the pre- and post- questions to establish statistical significance. Subsequent analysis of these questions identified and traced patters and trends associated with learning and understanding across the three game runs. This research study draws on social constructivism and experiential learning as the dominant education theory that underpins it. Results revealed that for all three game runs learning took place. Participants identified dominant themes and environmental dimensions both before and after playing the ACG. The analysis of these responses indicated a deeper awareness of water as a contributing factor for sustainable economic development while the game runs enabled the researcher to adjust the water availability within each game run until rainfall and water management processes representative of a southern African context were successfully simulated in the last game run.
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