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Invariant control systems and sub-Riemannian structures on lie groups: equivalence and isometries

  • Authors: Biggs, Rory
  • Date: 2015
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/64815 , vital:28607
  • Description: In this thesis we consider invariant optimal control problems and invariant sub-Riemannian structures on Lie groups. Primarily, we are concerned with the equivalence and classification of problems (resp. structures). In the first chapter, both the class of invariant optimal control problems and the class of invariant sub-Riemannian structures are organised as categories. The latter category is shown to be functorially equivalent to a subcategory of the former category. Via the Pontryagin Maximum Principle, we associate to each invariant optimal control problem (resp. invariant sub-Riemannian structure) a quadratic Hamilton-Poisson system on the associated Lie-Poisson space. These Hamiltonian systems are also organised as a category and hence the Pontryagin lift is realised as a contravariant functor. Basic properties of these categories are investigated. The rest of this thesis is concerned with the classification (and investigation) of certain subclasses of structures and systems. In the second chapter, the homogeneous positive semidefinite quadratic Hamilton-Poisson systems on three-dimensional Lie-Poisson spaces are classified up to compatibility with a linear isomorphism; a list of 23 normal forms is exhibited. In the third chapter, we classify the invariant sub-Riemannian structures in three dimensions and calculate the isometry group for each normal form. By comparing our results with known results, we show that most isometries (in three dimensions) are in fact the composition of a left translation and a Lie group isomorphism. In the fourth and last chapter of this thesis, we classify the sub-Riemannian and Riemannian structures on the (2n + 1)-dimensional Heisenberg groups. Furthermore, we find the isometry group and geodesics of each normal form.
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The diversity of root fungi associated with Erica species occurring in the Albany Centre of Endemism

  • Authors: Bizabani, Christine
  • Date: 2015
  • Subjects: Ericaceae , Ericas , Roots (Botany) -- Diseases and pests , Mycorrhizal fungi , Polymerase chain reaction , Fungi -- Classification
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4160 , http://hdl.handle.net/10962/d1018575
  • Description: South Africa has the highest species diversity of ericaceous plants belonging to the Erica genus. There are over 850 identified species in the Cape Floral Region. The Albany Centre of Endemism (ACOE) is located within this region and is a hotspot of diversity consisting of various plant genera. The success of Erica plants is ubiquitously attributed to mycorrhizal relationships they engage in with a diverse group of fungi. This symbiosis is known as the ericoid mycorrhizal (ERM) association. The overall aim of this study was to establish the diversity of root fungi associated with Erica plants using morphological, molecular and 454 pyrosequencing techniques. Six Erica species were identified using leaf and flower morphology according to taxonomic keys. The identified plants were Erica cerinthoides, Erica demissa, Erica chamissonis, Erica glumiflora, Erica caffra and Erica nemorosa. Roots from sampled plants were stained and examined microscopically to determine their mycorrhizal status. Ericoid mycorrhizal associations together with dark septate endophyte (DSE) structures and hyphae that did not form any specific structure were observed in all the roots. In addition arbuscular mycorrhizal (AM) structures in the form of vesicles were detected in E. glumiflora and E. cerinthoides. In order to identify the culturable fungi associated with the respective hosts, sterilised roots were placed on various culture media for cultivation. Thereafter isolated fungi were morphologically classified into 67 morphotypes. These were mostly sterile and darkly pigmented. Non-sporulating mycelia of variable colouration such as white, cream-yellowish, beige, green and brown were also observed. Further identification was carried out using molecular techniques. DNA was extracted separately from pure cultures and amplified using ITS1 and ITS4 primers in a polymerase chain reaction (PCR). Thereafter sequencing and Basic Local Alignment Search Tool (BLAST) were used to identify the isolates to generic level. The fungi were taxonomically classified into 54 operational taxonomic units and 94 percent were Ascomycetes and Helotiales was the dominant order. Unclassified Helotiales with affinities to fungi currently identified as Epacrid root fungus was common in all hosts. Other isolates that were identified included Oidiodendron, Meliniomyces, Phialocephala, Cadophora, Lachnum, Leohumicola Cryptosporiopsis, Chaetomium, Acremonium and Epicoccum species. Basidiomycetes were represented by two OTUs belonging to the genus Mycena. Four OTUs comprised fungi that had no significant alignments in the reference databases. Direct root DNA extraction together with 454 pyrosequencing was used to detect the diversity of culturable and unculturable fungi associated with the identified hosts. The ITS2 region was targeted for sequencing. Although Ascomycetes remained the dominant phyla, Basidiomycetes were also detected in all host plants. Glomeromycota was present in E. caffra and E. cerinthoides. Helotiales was dominant in all Erica plants with the exception of E. cerinthoides and E. chamissonis which were dominated by the order Chaetothyriales. The OTUs identified to genus level included Epacris pulchella root fungus, Oidiodendron cf. maius, Acremonium implicatum, Leohumicola, Lachnum, Capronia and Mycena species. Culture-based techniques and pyrosequencing detected similar fungal composition comprising Ascomycetes, while, pyrosequencing was able to detect Glomeromycetes and Basidiomycetes.
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The interrelationships between foreign direct investment and economic growth in Africa

  • Authors: Bolani, Lindelwa Mandisa
  • Date: 2015
  • Subjects: Investments, Foreign -- Africa , Economic development -- Africa , Africa -- Economic conditions -- 1960- , Africa -- Foreign economic relations , Gross domestic product -- Africa
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:1123 , http://hdl.handle.net/10962/d1019885
  • Description: There has been a long search for the keys to development and economic growth in Africa. This study investigates the relationship between FDI and economic growth over the period 2000-2012 using data from 48 African countries. On the aggregate regional level FDI and economic growth were found to be positively correlated during this period. Using panel data econometric techniques and the Panel Granger Causality test, results revealed that a bi-directional causality relationship existed between FDI and GDP. Thus, the results suggest that GDP is a requirement for increased investment, and at the same time is the result of increased foreign investment. Thus, the conclusion is that African policy makers are justified in increasing their attempts to create an attractive business environment for foreign investors, as it is beneficial for economic growth.
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Performance management of health professionals : an evaluation research study of health services in the subdistrict of Buffalo City in the Provincial Department of Health in the Eastern Cape

  • Authors: Booi, Mlungisi Wellington
  • Date: 2015
  • Subjects: South Africa -- Department of Health , Batho Pele (Program) , Public health personnel -- South Africa -- Buffalo City , Employees -- Rating of -- South Africa -- Buffalo City , Public health -- South Africa -- Buffalo City -- Evaluation , Customer services -- South Africa -- Buffalo City -- Evaluation , Employees -- Training of -- South Africa -- Buffalo City , Employee-management relations in government -- South Africa -- Buffalo City
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:859 , http://hdl.handle.net/10962/d1020017
  • Description: Integrative Summary In 1997 the Minister of Public Service and Administration of South Africa, Zola Skweyiya, introduced the White Paper on Transforming Public Service Delivery(Department of Public Service and Administration(DPSA,1997: 1). It was premised on what was called Batho Pele (DPSA, 1997: 9), giving effect to Section 197 of the Constitution, Act 108 of 1996 as amended. A linkage to performance management can be found from the assertion made in the White Paper that in future the Batho Pele would form the basis of any assessment of the performance of individual staff and that would contribute to improving the delivery of service (DPSA, 1997:16). Another factor that contributed to the utilisation of a performance management system was the recommendation put forward by the Public Service Commission of South Africa( PSC,2004: 16),that called for public institutions to adopt a clear, comprehensive performance management and evaluation framework for the delivery of public service. That was expected to turn around the ailing public institutions whose record of serving the public with pride and dignity was on the decline. The research aim was to evaluate the effectiveness of the performance management system in creating and resolving role conflict with health professionals employed by the Buffalo City sub-district. The research goal was divided into three objectives, namely: evaluation of the effectiveness of the performance management system as a managerial tool for health managers to manage their subordinates including both professional and support staff, evaluation of the effectiveness of the performance system from the perspective of the health professional as a subordinate and to analyze the functioning and effectiveness of the system in creating and resolving role conflict between professional conduct and organisational requirements. The respondents noted that the implementation of the system was not matched with appointment at managerial level with officials having relevant managerial capacity. Further to that resources at the coal face of service delivery continued to deteriorate and became very scarce and there is no documented proof that has been found of an effort made to check the compatibility of the system to health professionals. The literature identified negative effects that have emanated from the implementation of the performance management system. The study was conducted by interviewing health professionals from the entry level to the management level within the Buffalo City sub-district from three mini hospitals or Health Care Centres. The respondents indicated that there are positives that have been achieved by the implementation of the system, such as the skills gap identification as well as specific targets contained in annual performance contracts. These targets help motivate health professional to focus on that particular direction of activities. Unfortunately it has been clearly documented that the performance management system has also contributed to the development of role conflict in a number of professionals. It has been documented that the system has not been crafted with a health professional in mind and, as such, appears to favour quantity rather than quality of health services as advocated by the codes of practice of different health professionals. There are a number of recommendations that were put forward by the respondents to try to salvage the system and in mitigation of the identified negative factors. For the improvement of the system, the Eastern Cape Provincial Department of Health has to firstly customise the annual contracts to contain only the fundamental information. Secondly need to improve the transparency pertaining to financial pressures facing the Health Department. Thirdly the provision of essential enablers, need to be prioritised. Fourthly there is a need to upgrade the system to incorporate 360 degree feedback. Further research recommendations include a bigger sample incorporating different research methods and to also incorporate searches for measures that can be implemented to improve the system to be more relevant to health professionals. This document is organised and presented in three sections. The first section is the evaluation report with a review of literature, research methodology, findings, discussion and conclusion. The second section is where an indepth literature review is located and the last section details the research methodology.
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The cheetahs of the Northern Tuli Game Reserve, Botswana: population estimates, monitoring techniques and human-predator conflict

  • Authors: Brassine, Eleanor I
  • Date: 2015
  • Subjects: Cheetah -- Botswana , Northern Tuli Game Reserve , Animal populations -- Botswana
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5922 , http://hdl.handle.net/10962/d1017800
  • Description: Remaining viable cheetah (Acinonyx jubatus) populations in Africa are threatened by direct persecution through conflict with farmers and habitat degradation and fragmentation. Botswana is considered a stronghold for free roaming cheetahs in Africa, yet the country has had relatively limited research on its cheetahs, and information from the east of the country is lacking. Data on the current status of populations is thus required to make informed management decisions. My study provides estimates of population density, abundance, distribution and status for the demographically open cheetah population of the Northern Tuli Game Reserve (NOTUGRE) in Botswana. The effectiveness of two population monitoring methods, namely camera trapping and a photographic survey, were also investigated. Moreover, I report on the level of conflict between livestock farmers and predators on rural communal farmlands within and adjacent to NOTUGRE. Data were collected between May 2012 and November 2013. Results indicate a low population density of 0.61 ± 0.18 adult cheetahs per 100 km² and a minimum population size of 10 individuals (nine adults and one cub). Camera traps placed at cheetah scent-marking posts increased detection rates and provided ideal set up locations. This approach, together with Spatial Explicit Capture- Recapture (SECR) models, is recommended for future studies. The long-term studies that are required to better understand the status of cheetahs in Botswana do not exist. Thus, photographic surveys may provide an alternative method for providing baseline data on population numbers, distribution and demography. The third aspect of my study gathered information on levels of livestock loss and human tolerance of predators through the use of interviews (n = 80). Conflict with subsistence farmers is a concern as livestock depredation is relatively high (9.1% of total livestock owned) and farmers had an overall negative attitude towards conservation of large predators. My results suggest that human-predator conflict in this area is more complex than the direct financial loss from depredation. Hence, reducing depredation rates alone is unlikely to change farmer tolerance of wildlife on farmlands. Improved, responsible farm management, including self-responsibility for livestock rearing, and positive appreciation for wildlife are necessary. The NOTUGRE cheetah population requires further research to understand possible threats to the population. Furthermore, a better understanding of the connectivity between cheetahs of NOTUGRE, South Africa and Zimbabwe is required. The number of cheetahs within NOTUGRE is too small to sustain a viable population, hence conserving cheetahs outside of the protected area should be a priority for the conservation of the population. This can only be achieved through assistance and involvement from national authorities, local people and conservation organisations.
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Sport consumption patterns in the Eastern Cape: cricket spectators as sporting univores or omnivores

  • Authors: Brock, Kelcey
  • Date: 2015
  • Subjects: Cricket -- South Africa -- Eastern Cape , Cricket -- Social aspects , Consumption (Economics) , Consumer behavior
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:1115 , http://hdl.handle.net/10962/d1017534
  • Description: Since its inception, consumption behaviour theory has developed to account for the important social aspect that underpins or at least to some extent can be used to explain consumption behaviour. Modern consumption behaviour theory is anthropocentric in nature, with people and societal influence at the forefront of the theory. To date, empirical studies on consumption behaviour of cultural activities (for example, music and arts), entertainment and sport have used Bourdieu’s (1984) omnivore/univore theory to suggest that consumption of leisure activities is bound up in social ties. To date, no such investigation has been conducted in the context of sport in South Africa. The aim of the study therefore is to investigate whether South African cricket spectators are sporting omnivores or univores, thus, essentially investigating whether sports consumption behaviour in South Africa is bound up in social ties. A number of positive economic and social ramifications could result from gaining a holistic understanding of sports consumption behaviour in South Africa. Given these ramifications, the secondary goal of the research is to identify motives for consumers making specific sport consumption decisions, and determining whether certain characteristics can be attributed to these consumption decisions. Recommendations based on the findings of the research could help various stakeholders understand sports consumption patterns in South Africa, which could in turn lead to the realization of positive economic and social benefits. The study made use of a questionnaire, administered at four different limited overs cricket matches in the 2012/13 cricket season, to obtain a range of responses reflecting specific types of consumption behaviour as well as motives for consumption decisions of cricket spectators in the Eastern Cape. Using individual binary probit models and post estimation F-tests, the results indicate that consumption behaviour of sport within South Africa predominantly differs on the grounds of education and race. This suggests that there are aspects of social connotations underpinning sports consumption behaviour within South Africa
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An evaluation of the potential for implementing adaptive co-management in the Waodani social-ecological system in the Ecuadorian Amazon

  • Authors: Bryja, Malgorzata Anna
  • Date: 2015
  • Subjects: Adaptive natural resource management -- Ecuador -- Reserva de Biosfera Yasuni , Huao Indians -- Ecuador -- Reserva de Biosfera Yasuni , Natural resources -- Co-management -- Ecuador -- Reserva de Biosfera Yasuni , Social ecology -- Ecuador -- Reserva de Biosfera Yasuni , Sustainable development -- Ecuador -- Reserva de Biosfera Yasuni , Resource-based communities -- Ecuador -- Reserva de Biosfera Yasuni , Reserva de Biosfera Yasuni (Ecuador) -- Economic conditions , Huao Indians -- Ecuador -- Reserva de Biosfera Yasuni -- Economic conditions
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4784 , http://hdl.handle.net/10962/d1018192
  • Description: Adaptive co-management (ACM), one of the most prominent management approaches to emerge in the recent years, combines iterative learning, flexibility, and adaptation promoted by adaptive management with the principles of nurturing diversity and fostering collaboration among different partners that underpin co-management philosophy. ACM has been proposed as an approach to address the deficiencies of centralized management in ensuring sustainability of social-ecological systems (SESs) in face of future uncertainties. This thesis aims to evaluate the readiness of resource users (the Waodani) as well as external actors (the Ecuadorian State and NGOs) for future implementation of ACM and thus enhancing the long-term social-ecological sustainability of the Waodani SES located in the Yasuni Biosphere Reserve in the Ecuadorian Amazon. Qualitative data obtained by means of focus groups with the Waodani and individual interviews with external actors and Waodani leaders revealed different levels of readiness for ACM. Firstly, in the case of the Waodani, the insufficient fulfillment of some conditions required for successful ACM as well as intercommunity differences in regards to these conditions can complicate the implementation of ACM, unless sufficient external assistance is offered to the SES. The analysis of NGOs demonstrated, on the other hand, a relative readiness for ACM, providing that such aspects as sufficient funding, long-term commitment to collaboration, and inter-institutional linkages are strengthened. The study also found that the Ecuadorian government’s potential to contribute to ACM is hindered by the lack of readiness to work with the indigenous society as well as by funding and communication challenges. Furthermore, the resource based economy supported by the State limits the scope of innovation and adaptation. Still, as in the case of other actors, overcoming the challenges and transitioning towards adaptive governance and thus ACM could be possible in the long-term, if recent legal and political changes are truly implemented.
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Using a classroom library to promote extensive reading in a Grade 8 class in a Fort Beaufort District School, Eastern Cape : an action research case study.

  • Authors: Bushula, Bruce Simphiwe
  • Date: 2015
  • Subjects: Classroom libraries -- South africa -- Eastern Cape -- Case studies , Reading (Secondary) , Literacy -- Study and teaching (Secondary) , Literacy programs
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2022 , http://hdl.handle.net/10962/d1017333
  • Description: This thesis reports on a collaborative action research case study with Grade 8 learners in a rural high school in Fort Beaufort District, Eastern Cape, South Africa. The goals of the case study were firstly, to understand best practices for promoting extensive reading using a classroom library, and secondly, to use these insights to put an extensive reading programme in place with a view to improving my practice as a language teacher and to gain better understanding of ways of enhancing my Grade 8 learners’ literacy skills. The following qualitative methods were used to collect data: observation, semi-structured interviews, class discussion, questionnaires, journal reflections and document analysis. Analysis of data involved identification of emerging themes and patterns. The findings suggest that the strategies used in the extensive reading intervention improved my learners’ levels of engagement with reading. Putting these strategies into practice, and reflecting critically on how to refine them helped enrich my own professional insight and development in relation to the implementation of extensive reading programmes. Since action research is usually designed in spirals of action, this research serves as a first spiral and a foundation upon which to build second and subsequent spirals (which do not form part of this research). The study highlighted the fact that certain challenges that emerged (for example, shortage of books at the learners’ level, and a lack of parental cooperation) need to be addressed in a second spiral of intervention. The study further suggested that the implementation of effective extensive reading programmes by teachers in the middle and upper phases of secondary schooling requires further investigation.
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The Ecca type section (Permian, South Africa) : an outcrop analogue study of conventional and unconventional hydrocarbon reservoirs

  • Authors: Campbell, Stuart Alexander
  • Date: 2015
  • Subjects: Hydrocarbon reservoirs -- Ecca Group , Geology, Stratigraphic -- Permian , Paleogeography -- Ecca Group , Shale gas -- Ecca Group , Shale gas reservoirs -- Ecca Group , Ecca Group , Ripon Formation (South Africa) , Collingham Formation (South Africa)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5083 , http://hdl.handle.net/10962/d1018199
  • Description: The Karoo Basin of South Africa holds an estimated 906 billion to 11 trillion cubic meters of unconventional shale gas within the shales of the Whitehill and Collingham formations of the Ecca Group. Evaluation of this potential resource has been limited due to the lack of exploration and a scarcity of existing drill core data. In order to circumnavigate this problem this study was undertaken to evaluate the potential target horizons exposed in outcrops along the southern portion of the Karoo Basin, north of Grahamstown in the Eastern Cape Province. Detailed field logging was done on the exposed Whitehill and Collingham formations as well as a possible conventional sandstone (turbidite) reservoir, the Ripon Formation, along road cuttings of the Ecca Pass. Palaeocurrent data, jointing directions and fossil material were also documented. Samples were analysed for mineralogy, porosity, permeability, and total organic carbon content (TOC). The extensively weathered black shales of the Whitehill Formation contain a maximum TOC value of 0.9% and the Collingham Formation shales contain a maximum TOC value of 0.6%. The organic lithic arkose sandstones of the Ripon Formation are classified as ‘tight rock’ with an average porosity of 1% and an average permeability of 0.05 mD. The Whitehill Formation in the southern portion of the Karoo Basin has experienced organic matter loss due to low grade metamorphism as well as burial to extreme depths, thus reducing shale gas potential. The Ripon Formation is an unsuitable conventional reservoir along the southern basin boundary due to extensive cementation and filling of pore spaces.
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Towards a Mobile Bioethanol Unit for point of source conversion of sugar sources to bioethanol: design and feasibility study for South Africa

  • Authors: Cech, Alexandra Louise
  • Date: 2015
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/59141 , vital:27439
  • Description: Restricted access-thesis embargoed for 5 years
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Production of Cydia pomonella granulovirus (CpGV) in a heteralogous host, Thaumatotibia Leucotreta (Meyrick) (False codling moth)

  • Authors: Chambers, Craig Brian
  • Date: 2015
  • Subjects: Cryptophlebia leucotreta -- South Africa , Codling moth -- South Africa , Apples -- Diseases and pests -- South Africa , Codling moth -- Biological control -- South Africa , Insect pests -- Biological control -- South Africa , Biological pest control agents -- South Africa , Baculoviruses -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5935 , http://hdl.handle.net/10962/d1017906
  • Description: Cydia pomonella (Linnaeus) (Family: Tortricidae), the codling moth, is considered one of the most significant pests of apples and pears worldwide, causing up to 80% crop loss in orchards if no control measures are applied. Cydia pomonella is oligophagous feeding on a number of alternate hosts including quince, walnuts, apricots, peaches, plums and nectarines. Historically the control of this pest has been achieved with the use of various chemical control strategies which have maintained pest levels below the economic threshold at a relatively low cost to the grower. However, there are serious concerns surrounding the use of chemical insecticides including the development of resistance in insect populations, the banning of various insecticides, regulations for lowering of the maximum residue level and employee and consumer safety. For this reason, alternate measures of control are slowly being adopted by growers such as mating disruption, cultural methods and the use of baculovirus biopesticides as part of integrated pest management programmes. The reluctance of growers to accept baculovirus or other biological control products in the past has been due to questionable product quality and inconsistencies in their field performance. Moreover, the development and application of biological control products is more costly than the use of chemical alternatives. Baculoviruses are arthropod specific viruses that are highly virulent to a number of lepidopteran species. Due to the virulence and host specificity of baculoviruses, Cydia pomonella granulovirus has been extensively and successfully used as part of integrated pest management systems for the control of C. pomonella in Europe and around the world, including South Africa. Commercial formulations have been typically based on the Mexican strain of CpGV. However due to long-term multiple applications of CpGV and the reliance on CpGV in organic farming practices in Europe, resistance to the CpGV-M strain has developed in a number of field populations of C. pomonella. This study aimed to identify and characterize novel isolates of CpGV in South Africa and compare their virulence with the commercial standard CpGV-M. Secondly, since C. pomonella is difficult to culture on a large scale, an alternate method of CpGV production was investigated in order to determine if CpGV could be produced more efficiently and at a reduced cost without negatively impacting the quality of the product. Several isolates of CpGV were recovered either from field collected larvae or from a laboratory-reared C. pomonella colony. Characterisation of DNA profiles using a variety of restriction enzymes revealed that only a single isolate, CpGV-SA, was genetically different from the Mexican strain of the virus used in the commercially available CpGV based products in South Africa. In dose-response bioassays using CpGV-SA, LC₅₀ and LC₉₀ values for neonate C. pomonella larvae were 3.18 x 10³ OBs/ml and 7.33 x 10⁴ respectively. A comparison of these values with those of CpGV-M indicated no significant difference in the virulence of the two isolates under laboratory conditions. This is a first report of a genetically distinct CpGV isolate in South Africa. The biological activity and novelty of CpGV-SA makes this isolate a potentially important tool for CpGV resistance management in South Africa. In order to justify production of CpGV in an alternative host, studies on the comparative biological performance of C. pomonella and T. leucotreta based on oviposition, time to hatch, larval developmental times and rearing efficiency as well as production costs were performed. Thaumatotibia leucotreta was found to be more fecund and to have significantly shorter egg and larval developmental times. In addition, larval production per unit of artificial diet was significantly higher than for C. pomonella. This resulted in T. leucotreta being more cost effective to produce with implications for reduced insectary space, sanitation practices as well as the labour component of production. Virus yield data generated by inoculation both C. pomonella and T. leucotreta with nine concentrations of CpGV resulted in comparable virus yields, justifying the continuation of the research into production of CpGV in T. leucotreta. It was important to determine the LC and LT values required for mass production of CpGV in late instar T. leucotreta larvae. Dose- and time-response bioassays with CpGV-M were conducted on artificial diet to determine these values. Fourth instar LC₅₀ and LC₉₀ values were 5.96 x 10³ OBs/ml and 1.64 x 10⁵ OBs/ml respectively. LT50 and LT90 values were 81.10 hours and 88.58 hours respectively. Fifth instar LC₅₀ and LC₉₀ values were 6.88 x 10⁴ OBs/ml and 9.78 x 10⁶ OBs/ml respectively. LT₅₀ and LT₉₀ values were 111.56 hours and 137.57 hours respectively. Virus produced in fourth instar T. leucotreta larvae was bioassayed against C. pomonella neonate larvae and compared to CpGV-M to establish if production in the heterologous host negatively affected the virulence of the isolate. No significant difference in virulence was observed between virus produced in T. leucotreta and that produced in C. pomonella. The data generated in the bioassays was used in CpGV mass production trials to evaluate production. All production methods tested produced acceptable virus yields. To examine the quality of the virus product, genomic DNA was extracted from larval cadavers and subjected to REN analysis with HindIII. The resulting DNA profiles indicated that the virus product was contaminated with the homologous virus, CrleGV. Based on the above results, the use of T. leucotreta as an alternate host for the in vivo production of CpGV on a commercial basis is not at this stage viable and requires further investigation before this production methodology can be reliable used to produce CpGV. However, this study has shown that CpGV can be produced in a homologous host, T. leucotreta and significant strides have been made towards developing a set of quality control standards that are essential for further development of successful production methodology. Finally a novel isolate of CpGV has been identified with comparable virulence to the CpGV-M. This is an important finding as it has broad reaching implications for resistance management of CpGV products in South Africa.
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An investigation into how two Grade 11 Physical Science teachers mediate learning of the topic chemical equilibrium : a case study

  • Authors: Chani, Fungisisai M
  • Date: 2015
  • Subjects: Chemical equilibrium -- Study and teaching (Secondary) -- Namibia , Science -- Study and teaching (Secondary) -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2023 , http://hdl.handle.net/10962/d1017334
  • Description: The Namibian Physical Science Higher Level Syllabus requires students to study the topic on chemical equilibrium. This section has proven to be one of the most difficult for Namibian learners as reflected by their poor responses to questions in the Grade 12 NSSC ‘H’ examinations. Triggered by these discoveries, I decided to conduct a research on how teachers mediate learning of the topic on chemical equilibrium in a Namibian context. Conducted at a private school in Windhoek, the study involved two experienced Grade 11 Physical Science teachers renowned for good results. I adopted a qualitative case study underpinned by an interpretive paradigm. Sense making of concepts on chemical equilibrium was my unit of analysis. To generate data, I used document analysis, semi-structured interviews, lesson observations, which were videotaped as well as stimulated recall interviews. Vygotsky’s mediation of learning and social constructivism blended with Shulman’s pedagogical content knowledge (PCK) were the theoretical frameworks adopted in the study. During the analysis process, there was grouping of data into categories. These included teacher-learner interactions as emphasized by Vygotsky’s mediation of learning and learners’ challenges according to PCK. I used an inductive approach to identify emerging themes from my data. The themes were colour coded and the developed into analytical statements. Data triangulation, member checking, and peer review ensured data validity and trustworthiness. Stimulated recall interviews conducted while watching the videos with the two teachers, complemented these approaches. My findings were that teachers extensively used various meditational tools such as prior knowledge, language, analogies and an equilibrium game to mediate learning. The teachers experienced numerous challenges during mediation of learning, including language difficulties and learners’ failure to comprehend complex chemical equilibrium concepts. Notwithstanding, the teachers in this study managed to some extent to overcome the challenges by exhibiting facets of advanced PCK.
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Engaging within zones of proximal development on Facebook : the case of using Facebook to support learning and mentoring on a NQF Level 5 environmental education, training and development practices learnership

  • Authors: Chetty, Preven
  • Date: 2015
  • Subjects: Social media -- Study and teaching (Higher) -- South Africa , Internet in education , Online social networks , Organizational learning , Employees -- Training of , Group work in education
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2024 , http://hdl.handle.net/10962/d1017335
  • Description: This study focuses on two roll-outs of a, year-long National Qualification Framework (NQF) level 5, environmental education learnership in South Africa and attempts at enhancing collaborative learning at workplaces using a familiar social networking site called Facebook. This study uses the Facebook group sites created for the workplace course component of the course as one of the means of data collection. Additional interviews and focus groups with learners and administrators on both Environmental Education Training and Development Practices (EETDP) courses also informed the study. The study is located within the context of the rise of the information age, its effects on socio-ecological landscape at large and ways of using social networking sites in order to facilitate scaffolding and meaning making within zones of proximal development for environmental education learnerships. It also looks at the model of apprenticeship and workplace based learning as it is broadly located at the nexus of the SAQA-led academic inquiry into workplace based learning and professional development. It was found that the use of Facebook on the EETDP learnership allowed for collaborative learning to take place between peer to peer interactions as well as between tutors and learners. It was also noted that scaffolding processes requires both technical assistance and strong instructional input from course tutors. One of the most important findings in terms of collaborative learning and engaging within the Zone of Proximal Development (ZPD) was that learners were able to communicate more effectively and freely with both fellow learners and tutors on course after participating on the Facebook group sites. The study offers recommendations on how a social networking platform like Facebook can be utilised effectively for environmental education. The study recommends that scaffolding of workplace based tasks and concepts needs to be better integrated with the course and in both online and offline interactions between learners. It also illustrates how social networking sites can become powerful tools for creating meaning making when combined with course work.
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An empirical study on staff turnover and retention within Eskom : Eastern Cape Operating Unit

  • Authors: Chibba, Rajesh Chagan
  • Date: 2015
  • Subjects: Eskom (Firm) , Labor turnover -- South Africa -- Eastern Cape , Employee retention -- South Africa -- Eastern Cape , Job satisfaction -- South Africa -- Eastern Cape , Career development -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:847 , http://hdl.handle.net/10962/d1017514
  • Description: This research paper is broken up into three sections, namely an evaluation report, a literature review and a description of the research methodology. The evaluation report section is an assessment of the factors that could contribute to staff leaving the organisation and why staff would choose to remain with the organisation. The Distribution Division of Eskom is divided into nine separate Operating Units (OU's), in line with the nine Provinces. According to an Eskom Human Resource Manager (Mjali, 2013), as at March 2012 there were 2231 employees in the Easter Cape Operating Unit, while the staff turnover for the same period was 4.53%. Of the 101 staff that had resigned for the period 01 April 2011 to 31 March 2012, there were 27 transfers, 26 resignations and 30 retirements. The balance of 18 staff that left was due to dismissals and deaths. While the statistics suggest a healthy level of staff turnover at present, given the current pressures that Eskom employees are under, it is important to investigate their future intentions and to see what Eskom can do to continue to retain their services. The literature relating to staff turnover and retention was examined to determine the meaning of the terms retention and turnover and to review the relevant turnover topics that were emerging from the exit interview data. The research conducted was quantitative in nature, and a questionnaire was distributed to all managerial staff within the Eastern Cape Operating Unit of Eskom. The questionnaire was sent electronically to the participants via email with the link to the questionnaire. Participants were requested to respond on questions relating to factors on turnover and retention, and the responses were used to assess employee's intention to either remain with the organisation or to leave. The feedback received was analysed with the use of data analysis in Microsoft Excel (2010). The results of the research showed that there were two distinct themes related to employees' intention to remain with the organisation, namely job satisfaction and career development. On the other end of the scale, themes which would cause staff to want to leave the organisation were the performance management system of the organisation, not being listened to (i.e. to the ideas and views of staff) and leadership (i.e. the way the organisation was being led). Recommendations are made to management. The study also recommends future research that can be done to get greater insight into factors relating to staff turnover and retention. A detailed review of the literature is included in Section two of the report. Only essential components of the literature are included in Section one of report. Section three of the report provided a detailed description of the research design and the research procedure that was followed.
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Understanding the poverty-reducing livelihoods of child support grant caregivers in Riebeeck East, South Africa

  • Authors: Chikukwa, Vimbainashe
  • Date: 2015
  • Subjects: Archer, Margaret Scotford -- Political and social views , Child caregivers -- South Africa -- Riebeek-Oos , Public welfare -- South Africa -- Riebeek-Oos , Grants-in-aid -- South Africa -- Riebeek-Oos , Poverty -- South Africa -- Riebeek-Oos , Critical realism , South Africa -- Social conditions -- 1994- , South Africa -- Economic conditions -- 1991-
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:3393 , http://hdl.handle.net/10962/d1018196
  • Description: In 1994, racial domination in the form of apartheid ended in South Africa and the first postapartheid government was elected through a non-racial and democratic franchise. The new government inherited an entrenched system of racial inequality as well as widespread poverty amongst the formerly oppressed population, and it sought to address these challenges through policies of redistribution based on a new progressive constitution which emphasised the realisation of socio-economic rights. At the same time, and despite its redistributive measures, the post-apartheid government has pursued a macro-economic strategy with pronounced neoliberal dimensions. One of its critical redistributive measures focuses on social assistance to poor blacks, and this has entailed the construction and expansion of a massive social grant system including the child support grant which is received by millions of black South Africans on a monthly basis. The objective of this thesis is to examine and understand the livelihoods of child support grant recipients (or caregivers) in the context of conditions of extreme vulnerability marked by poverty. It does so by focusing on the small town of Riebeek East located in the Eastern Cape Province of South Africa. Though undoubtedly child support grant caregivers are victims of poverty, the thesis demonstrates that they are not without agency. They exist in structural conditions of vulnerability and poverty, but they nevertheless seek to manoeuvre and negotiate their way in and through their conditions of existence. This does not necessarily alleviate their poverty in any significant manner but it does show evidence of reflexivity, decision-making and responsibility in the pursuit of livelihood practices and outcomes. In making this argument, I draw upon the mega-theory of Margaret Archer (specifically, her morphogenetic approach) and the more middle-level perspective of the Sustainable Livelihoods Framework. Beyond contributing to the prevailing academic literature on the child support grant in South Africa, this thesis also hopefully makes a small contribution to controversies about structure and agency within sociology.
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Eliciting and combining expert opinion : an overview and comparison of methods

  • Authors: Chinyamakobvu, Mutsa Carole
  • Date: 2015
  • Subjects: Decision making -- Statistical methods , Expertise , Bayesian statistical decision theory , Statistical decision , Delphi method , Paired comparisons (Statistics)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5579 , http://hdl.handle.net/10962/d1017827
  • Description: Decision makers have long relied on experts to inform their decision making. Expert judgment analysis is a way to elicit and combine the opinions of a group of experts to facilitate decision making. The use of expert judgment is most appropriate when there is a lack of data for obtaining reasonable statistical results. The experts are asked for advice by one or more decision makers who face a specific real decision problem. The decision makers are outside the group of experts and are jointly responsible and accountable for the decision and committed to finding solutions that everyone can live with. The emphasis is on the decision makers learning from the experts. The focus of this thesis is an overview and comparison of the various elicitation and combination methods available. These include the traditional committee method, the Delphi method, the paired comparisons method, the negative exponential model, Cooke’s classical model, the histogram technique, using the Dirichlet distribution in the case of a set of uncertain proportions which must sum to one, and the employment of overfitting. The supra Bayes approach, the determination of weights for the experts, and combining the opinions of experts where each opinion is associated with a confidence level that represents the expert’s conviction of his own judgment are also considered.
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Perceived undersupply of local labour in the presence of unemployment: a case of selected Sundays River Valley citrus farms, 2013

  • Authors: Chirara, Malon Tinotenda
  • Date: 2015
  • Subjects: Unemployment -- South Africa -- Sundays River (Eastern Cape) , Citrus fruit industry -- South Africa -- Sundays River (Eastern Cape) , Labor market -- South Africa -- Sundays River (Eastern Cape) , Work environment -- South Africa -- Sundays River (Eastern Cape) , Agricultural wages -- South Africa -- Sundays River (Eastern Cape) , Agricultural laborers -- South Africa -- Sundays River (Eastern Cape) , Seasonal labor -- South Africa -- Sundays River (Eastern Cape) , Migrant agricultural laborers -- South Africa -- Sundays River (Eastern Cape) , Personnel management -- South Africa -- Sundays River (Eastern Cape)
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:1125 , http://hdl.handle.net/10962/d1020367
  • Description: While skilled labour shortages are common in many countries, including South Africa, mainly due to a skills mismatch, the undersupply of unskilled labour was less expected, especially in developing countries with high unemployment. The thesis utilises data on perceived worker undersupply on selected citrus farms in the Sundays River Valley (SRV), located in the Eastern Cape Province of South Africa, collected in 2013, to analyse why unemployed residents, surprisingly, do not fill up vacancies on farms. In contrast to other labour markets, farm employment is not restricted by educational levels and as workers reported, with little training the various job tasks and skills required are easy and quick to grasp. At a time the government is trying to find ways of reducing unemployment, and the SRV Municipality (2012:29) reported approximately 42% unemployment, the question arises as to why the relatively low educated residents do not take advantage of the employment opportunities on farms. According to local workers and unemployed residents, the farm job was unattractive largely because of a combination of two factors: perceived relatively low salaries partly caused by the availability of migrant seasonal workers accepting lower remuneration and poor non-wage working conditions. The survey also found that farmers preferred migrant workers because they were more productive compared to their local counterparts who were, reportedly, characterised by high absenteeism and laziness, caused mainly by a reliance on social grants and alcohol abuse. Other reasons given for the unattractiveness of the farm job included the seasonal nature of farm employment, which left workers with no source of income in the offseason, the redundancy associated with farm tasks, perceived poor treatment of workers and lack of information on UIF and Provident funds to farm workers. To address problems associated with the dislike of farm work, seasonality of on-farm employment and the reportedly relatively low income, farm managers, the local municipality and the Labour Department could possibly be involved in creating more communal agricultural projects and help provide local community members to venture into supporting alternative careers within the Hospitality, Ecotourism and Conservation Industries through training programmes. Farm managers may need to consider improving their working relationship with workers in communication and when assigning tasks. Farmers and the local municipality could also consider investing in training programmes for the unemployed residents to equip them with technical skills that can improve their chances of finding jobs.
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Synthesis and biological evaluation of truncated sarganaphthoquinoic acid derivatives as Hsp90 inhibitors

  • Authors: Chiwakata, Maynard T
  • Date: 2015
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/64708 , vital:28594
  • Description: Hsp90 inhibition has been at the centre of attention in current research due to the possibility of “cracking down” on the entire process leading to the development of malignant cancers. Small underlying principles common in all types of cancers have been determined that govern the transformation of normal human cells into cancerous cells, with all relying on the ATPase activity of Hsp90 protein. Hsp90 protein is therefore an attractive drug target that if successfully inhibited can result in the remission of cancer tumours by one form of treatment. To date, no Hsp90 inhibitor has been sanctioned for cancer treatment as most are still in clinical development. Our research was therefore inspired by reports that indicated the potential of quinones / naphthoquinones to act as Hsp90 inhibitors. Preliminary results of a few selected marine natural product quinone systems i.e. sargaquinoic acid (SQA) (2.47) and lapachol (3.6) showed moderate cytotoxicity and weak interactions with the Hsp90 molecular chaperone, and evidence suggested C-terminal binding of these molecules. No correlation has been determined yet between cytotoxicity and Hsp90 inhibition, hence we aimed to develop natural product inspired molecules that exhibit both cytotoxic and Hsp90 inhibition properties. Due to limited amounts of the natural product that can be acquired from natural sources, synthetic analogues were opted for. Isolation of a few selected quinones was conducted to have material that could be used in biological assays. For structural modifications, a series of truncated naphthoquinone systems were prepared adopting the sarganaphthoquinoic acid (3.5) scaffold. The naphthoquinones were prepared via Diels-Alder reactions of relevant benzoquinones with myrcene, followed by aromatization reactions using MnO2. Various alkyl and aryl amines were then coupled to the C-2/3 position of the naphthoquinone using Michael’s addition reactions. Tricyclic naphthoquinones were also synthesized from reactions with hypotaurine and citral. Design of the analogues incorporated functionalities from known Hsp90 inhibitors e.g. geldanamycin (2.28) and its analogues. Preliminary results obtained showed that coupling of naphthoquinones with aryl-amines resulted in the most cytotoxic compounds (4.14-4.19) with IC50 values as low as 0.3 μM against Hs578T breast cancer carcinoma (triple negative). Most of the alkyl amines (4.20-4.25) had IC50 values greater than 50 μM except for 4.20 and 4.21 that showed IC50 values of 7.6 μM and 2.6 μM respectively. Tricyclic naphthoquinones (4.28-4.29) showed moderate cytotoxic activity of approximately 10 μM. Hsp90 inhibition was assessed by client protein degradation assays, of which SQA (2.47), showed the best Hsp90 inhibition properties, followed by compound 4.20. The most cytotoxic arylamino-naphthoquinone (4.16) and tricyclic naphthoquinones (4.28-4.29) showed only moderate inhibition. None of the compounds led to Hsp70 induction, suggesting possible binding to the C-terminus of Hsp90. Interactions at the binding site were assessed by molecular docking studies and saturation transfer difference (STD) NMR. Docking studies were conducted on the N-terminus of Hsp90 and better binding was observed for arylamino naphthoquinones (4.14-4.19) than for other series of compounds. Unfortunately, the co-crystal structure for the C-terminus of Hsp90 is unavailable, hence docking study comparisons on both domains could not be conducted. However, STD NMR offered a platform to assess binding interactions between the naphthoquinones and the N- or C-terminal domains of Hsp90. However no interactions were observed at both the N- and C- termini of Hsp90 due to either weak binding of ligands to the protein or poor water solubility of the ligands. From these preliminary results, naphthoquinones bind to Hsp90 protein but conclusive remarks to which terminal domain they bind to could not be made. The best candidate from amongst the series of naphthoquinones prepared that showed moderate cytotoxicity and promising Hsp90 inhibition was compound 4.20. We therefore succeeded in developing a new series of naphthoquinones that possess moderate cytotoxicity and show Hsp90 inhibition.
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Conscientious objection and South African medical practitioners' constructions of termination of pregnancy and emergency contraception

  • Authors: Chiwandire, Desire
  • Date: 2015
  • Subjects: Abortion -- South Africa , Abortion -- Moral and ethical aspects -- South Africa , Emergency contraceptives -- South Africa , Contraception -- Moral and ethical aspects -- South Africa , Medical personnel -- Attitudes -- South Africa , Patients -- Legal status, laws, etc. -- South Africa , Reproductive rights -- South Africa , Women's rights -- South Africa , Liberty of conscience
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:2888 , http://hdl.handle.net/10962/d1017863
  • Description: Aim: The 1996 Choice on Termination of Pregnancy Act decriminalized abortion in South Africa and the South African Medicines Control Council in 2000 approved the dispensing of emergency contraceptive methods by pharmacists to women without a doctor's prescription. This legislation has been hailed as among the most progressive in the world with respect to women's reproductive justice. However the realisation of these rights in practice has not always met expectations in part due to medical practitioners' ethical objections to termination of pregnancy and the provision of related services. The aim of this study was to interpret the varying ways in which medical practitioners frame termination of pregnancy and emergency contraceptive services, their own professional identities and that of their patients/clients. Methods: Sample of 58 doctors and 59 pharmacists drawn from all nine provinces of South Africa. Data collected using an anonymous confidential internet-based self-administered questionnaire. Participants were randomly recruited from online listings of South African doctors and pharmacists practicing in both private and public sectors. Data were analysed using theoretically derived qualitative content analysis. Results: Participants drew on eight frames to justify their willingness or unwillingness to provide termination-of-pregnancy related services: the foetal life frame, the women's rights frame, the balancing frame, the social justice frame, the do no harm frame, the legal and professional obligation frame, the consequences frame and the moral absolutist frame. Conclusion: Health professionals' willingness or unwillingness to provide termination of pregnancy related services is highly dependent on how they frame or understand termination of pregnancy, and how they understand their own professional identities and those of their patients/clients.
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Love in a cold war

  • Authors: Christenson, Anna
  • Date: 2015
  • Subjects: South African fiction (English) -- 21st century
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: vital:5988
  • Description: A collection of short stories in two parts written in realist and fabulist styles. The first part looks at the post-war generation of baby boomers growing up in the American Midwest. The second half follows an American abroad and explores themes of disintegration, the shifting power balance in relationships and the terrible hole at the core of expatriate identity.
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