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An investigation of skills, knowledge and farmer support programmes of land reform beneficiaries :a case study of Forest Hill farmers in Kenton-on-Sea in the Ndlambe Local Municipality

  • Authors: Tshuma, Mengezi Chancellor
  • Date: 2013
  • Subjects: Land reforms -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , PhD (Agricultural Economics)
  • Identifier: vital:11205 , http://hdl.handle.net/10353/d1013109 , Land reforms -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
  • Description: black owners by white colonialists. Even though whites made up less than 20% of the nation‟s population, they took more than 80% of the agriculturally productive land and drove the original owners to the unproductive reserves where they were cramped and could not practice agriculture at all. Various acts such as the Black Land Act of 1913, Development Trust Act of 1936 and the Native Laws Amendment Act of 1937 were introduced which further frustrated the displaced black population thereby plunging it deeper and deeper into poverty. The main objective behind the introduction of these acts was to restrain the black population from earning livelihoods through agriculture thus forcing them to offer their labour to white farmers for low wages just to earn some form of livelihood. Such unfair practices and distribution of land prompted the first democratically elected government of South Africa to embark on a drive to redistribute the nation‟s land equitably amongst its citizens to foster national reconciliation, stimulate economic growth and compensate those that were forced out or lost their land during the apartheid era. This initiative was called the Land Reform Programme (LRP) and was implemented with three prongs namely (i) land redistribution; (ii) restitution; and (iii) land tenure. Among the beneficiaries of the LRP were farmers from a community called Marselle in Kenton-on-sea. In addition to getting land for farming purposes, the Marselle farmers also obtained financial support from the government‟s Land Bank to help them kick-start their farming activities. However, in spite of such interventions, they have struggled to turn their activities into sustainable livelihood sources. One most likely cause for this is the lack of farming knowledge and skills needed to make them more efficient and productive. This study was thus geared towards evaluating the knowledge and skills gap in Marselle which, when addressed, could make the Marselle farmers more productive. Its focus was limited to the 32 livestock and 8 chicory farmers that are recognized members of their respective projects. Focus was limited only to these farmers since the next phase of this study will involve building their capacity based on the skills gaps identified through this study. The findings showed that the two projects benefited at least 130 individuals belonging to the farming households, with 67.5% of these households headed by males. The age of these farmers was equally shared at 40% each between those above 65 years and those that only went as far as fourth grade. No one went to tertiary at all. At least 75% of the investigated farmers were unemployed and 42% of this population was pensioners. In terms of income though, 64.98% of it was from external sources. The Masakhane Silime (Chicory) project was implemented to generate income and provide job opportunities for the locals but neither of these objectives had been met at the time the data for this study was collected due to various challenges like lack of funds and infrastructure to enhance productivity. Just like the chicory project, the livestock project had its own objectives, namely; to remove animals from the residential areas, provide the animals with a safe place, reduce road accidents and also to provide a livelihood source for local farmers. Due to overgrazing the pastures, lack of proper camps and other challenges, some effort still needs to be put to achieve these objectives. Even though the livestock project was formed with these objectives in mind, the farmers themselves reared livestock either for personal consumption, selling, ritual purposes, store of wealth or all these combined. Regarding technical skills, livestock farmers were found to rely mostly on indigenous knowledge sources to attain farming knowledge. Only animal healthcare knowledge was popular to more than half the respondents. This was said to be due to the focus group meetings held on the farm every other Wednesday to share information with local extension officers. In spite of these information sharing events, livestock farmers identified training on how to feed; market; handle; and treat their livestock as key intervention knowledge areas. Attendance to these focus group meetings was limited to livestock farmers only. Various socio-economic factors were also found to have some form of influence on the acquisition of livestock knowledge. Education was the most dominant factor, with a significant association with the farmers‟ feeding (p=0.033); animal healthcare (P=0.038); marketing (p=0.009); veld management (p=0.036); and cattle slaughtering (p=0.027) knowledge. Other variables most influential include the gender and age of the household head. The former was significant at 95% confidence level for farmers‟ feeding knowledge (p=0.021); animal healthcare (p=0.039); marketing (p=0.043); livestock housing and handling (p=0.023); veld management (p=0.018); and cattle slaughtering (p=0.043). The dominance of males in acquiring these skills could be explained by the fact that the majority of the livestock project members were males. The majority of the few female members became members by default after the passing on of their husbands but their participation in the project was done through other project members who looked after their animals on their behalf. The number of farming years also had some positive and significant influence on other knowledge areas such as feeding (p=0.021) and livestock housing and handling (p=0.013). The logic supporting this association is that farmers tend to accumulate new and more skills the longer they stay in the same enterprise. In addition, most of the interviewed farmers were farm labourers prior to relocating to Marselle hence they acquired the necessary knowledge long before the project started. Concerning the chicory project, its members also relied heavily on indigenous knowledge sources for farming knowledge. Soil preparation (24.1%); planting (20.7%); land care (24.1%); and mechanical weed control (48.3%) were the knowledge areas lacked by more than half the respondents. The farmers identified land preparation (75%); communication skills (25%); marketing (100%); financial management (62%); and harvesting (88%) as the key crucial intervention areas they needed prioritized. As a study meant to inform the capacity building phase of the Land Bank project, this study identified the existing skills gaps in the two projects implemented in Forest Hill. When implementing the Capacity Building (CB) phase, various socio-economic factors will have to be considered. For example, the proposed intervention should not discriminate against anyone on the grounds of gender or physical abilities. The skills introduced should also be simple enough to be accepted and acquired even by the illiterate, especially when one considers the high illiteracy levels amongst the respondents. Efforts should also be made to create partnerships with the right organizations or groups of people so that they provide the required expertise and resources for the benefit of the farmers as and when required.
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  • Date Issued: 2013

An investigation of teachers' mathematical task selection in the Zambia context

  • Authors: Kangwa, Evaristo
  • Date: 2013
  • Subjects: Mathematics -- Study and teaching
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1384 , http://hdl.handle.net/10962/d1001512
  • Description: This research sought to investigate the sources and type of tasks used in the teaching of trigonometry in Zambia’s secondary schools, and to investigate the criteria used and decisions made by teachers in their selection and implementation of tasks. The study was conducted in three different school types located in high cost, medium cost and low cost respectively. One participant was chosen from each of the different categories of schools. The research was located within an interpretive paradigm. Data were collected through semi-structured interviews, lesson observations and document analysis which include: lesson plans for five consecutive days, pupils’ activity books and three textbooks predominantly used by the teachers. Document analysis was informed by the task analysis guide and essential themes which were used to tease out teachers’ task practice with regard to criteria used and decisions made in the selection and implementation of tasks. Essential themes that were qualitatively established were validated and explicated by the qualitative analysis. The findings of the study indicate that teachers picked tasks from prescribed textbooks. The study further suggests that teachers selected a mix of low and high level tasks, procedures without connections and procedures with connections tasks to be specific. There were no memorisations and doing mathematics tasks. Their choice of tasks was based on the purpose for which the task was intended. Some tasks were selected for the purpose of practicing the procedures and skills, other tasks for the promotion conceptual development. Most of high level tasks decline to low level tasks during implementation. The findings also indicate that teachers selected and implemented a variety of tasks and concepts. Furthermore, teachers presented tasks in various forms of representations and in a variety of ways. However, the results of this study could not be generalized because of the small sample involved. The results presented reflect the views and task practices of the target group. A possibility for future study would be to consider a large population, drawn across the country.
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  • Date Issued: 2013

An investigation of the criteria that create optimum tenant mix synergy in shopping centres

  • Authors: De Villiers, Garth Elroy
  • Date: 2013
  • Subjects: Retail trade , Shopping centers , Marketing
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:8756 , http://hdl.handle.net/10948/d1011658 , Retail trade , Shopping centers , Marketing
  • Description: The shopping centre has evolved into an integral part of modern day society. New generations especially are unable to imagine a world without shopping centres. In 2008 a world wide economic down turn emphasized the competition to attract a buying market to shopping centres, some centres thrived and some centres struggled. The need to understand what creates these different responses to highly competitive scenarios is discussed in this study, with particular attention given to the tenant mix that exists in different shopping centres. Criteria that determine an optimum tenant mix are examined and the constraining factors are discussed. A literature review of shopping centres is discussed and the evolution of the shopping centre to our current day understanding of the term shopping centre is examined. Accepted definitions and categorisations of shopping centres along with a brief history of the shopping centre, as revealed by the literature, is presented. To create a tenant mix the body of tenants needs to be divided into sub- categories and various ways to achieve this are examined. The objectives of this study are to determine what strategic approaches to managing the tenant mix exists in the literature and what factors determine the formulation of this mix. Furthermore the study examines to what extent these or other strategic approaches are used in practice and finally makes recommendations to promote the optimum tenant mix in shopping centres. A literature review was conducted to determine what the theory reveals about the shopping centre industry. This was followed by an empirical survey conducted in the Port Elizabeth area of the Nelson Mandela Metropole. Finally the findings and theory were compared to make conclusions and suggest recommendation to achieve synergy in shopping centres through a optimum tenant mix.
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  • Date Issued: 2013

An investigation of the discursive construction of the Tanganyika-Zanzibar Union as nation in the Union Day coverage in The Citizen and Daily News newspapers from 2005 to 2011

  • Authors: Dotto, Paul Casmir Kuhenga
  • Date: 2013
  • Subjects: Newspapers -- Research -- Tanzania , Press and politics -- Tanzania , Tanzania -- Politics and government -- 1964- , Zanzibar -- Politics and government -- 1964- , Press , Daily News , The Citizen , Union Day , Nation building
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: vital:3412 , http://hdl.handle.net/10962/d1001843
  • Description: This study is concerned with the constructions of the Tanzanian nation in the press. It has confined its focus, first, to the coverage from 2005 to 2011 on Union Day that marks the Union between Tanganyika and Zanzibar and the formation of the United Republic of Tanzania and, second, to two prominent Tanzanian newspapers, namely the state-owned Daily News, and the privately-owned The Citizen on Union Day. As the Union remains a contentious issue, the relevance of this research relates to the press’s considerable power to shape understandings and influence attitudes. The study works within a broad cultural and media studies framework and is informed by a constructionist approach to representation and to culture, and to nation in particular. It also draws of journalistic theories of agenda-setting and the normative roles of the press to probe the agendas set by the press on Union Day and to interrogate how the two newspapers construct and frame the Union of Tanganyika and Zanzibar as nation. The research responds to the question: ‘How has the Tanganyika-Zanzibar Union been represented in The Citizen and Daily News newspapers from 2005 to 2011?’ It employs quantitative and qualitative (thematic) content analysis to investigate the coverage in the editorials and feature articles of The Citizen and Daily News newspapers on Union Day (26 April) of 2005 to 2011. This study finds that the government-owned newspaper, Daily News, publishes more articles related to Union on Union Day than the privately-owned, The Citizen and collaborates more determinedly with the state in the process of constructing the nation. However, both newspapers adopt a collaborative role consistent with the development journalism tradition that endorses an informal partnership between media and the state in the process of development (Christians et al, 2009:201). Both publications tend to emphasise the hegemonic ideology pertaining to Union while giving limited attention to challenges to such constructions. While both newspapers do identify certain problems of the Union and thus exercise a monitorial role to varying extents, it is apparent that the press in Tanzania tends to be largely acritical, perhaps attributable to a long period under single party rule
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  • Date Issued: 2013

An investigation on how grade 8 learners make sens of static electricity through exploring their cultural beliefs and experiences about lightning: a case study

  • Authors: Nanghonga, Ottilie Mwanyenenange
  • Date: 2013
  • Subjects: Science -- Study and teaching (Secondary) -- Namibia Electrostatics -- Study and teaching (Secondary) -- Namibia Lightning -- Study and teaching (Secondary) -- Namibia , Static electricity , Cultural beliefs , Science -- Study and teaching (Secondary) -- Namibia , Electrostatics -- Study and teaching (Secondary) -- Namibia , Lightning -- Study and teaching (Secondary) -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1387 , http://hdl.handle.net/10962/d1001537
  • Description: Lightning as a natural phenomenon is shallowly presented in the Namibian curriculum documents such as the syllabus and textbooks. This gap in curriculum triggered my interest to investigate whether learners’ meaning-making in static electricity was enabled or constrained by elicitation and integration of their cultural beliefs and experiences about lightning and by their practical activities. This study was conducted with my grade 8 learners at the school where I am currently teaching. The school is located in a rural area in Ohangwena region in Northern Namibia. The study is situated within an interpretive paradigm. Within the interpretive paradigm, a qualitative case study approach was adopted. I considered this methodological orientation appropriate in this study as it allowed me to use the following data gathering methods: document analysis, brainstorming, discussions and presentations, semi-structured interview, focus group interview, observation and an assessment test. Multiple methods to gather data were used for triangulation and validation purposes. For data analysis purposes, the data sets were colour-coded to derive themes and analytical statements. Ethical considerations were also taken seriously in this study and all participants gave consent. An analysis of data revealed that there is no learning objective or basic competence in the Namibian Physical Science syllabus for grade 8-10 that requires learners to bring in their cultural beliefs and experiences, in particular, about lightning. Yet the study revealed that learners possess a lot of prior everyday scientific and non-scientific knowledge and experiences about lightning that they had acquired from their communities. Also, mobilization of learners' everyday knowledge and experiences about lightning enabled learner engagement during the science lessons. Likewise, engaging learners in practical activities in static electricity helped them to make meaning of scientific concepts. Based on my research findings, I therefore, recommend that learners' prior everyday knowledge and experiences about lightning should be incorporated during teaching and learning of the topic on static electricity.
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  • Date Issued: 2013

An investigation on how learners may use multiple representations in a social interaction to promote learning of percentages and fractions: a case study

  • Authors: Ngola-Kazumba, Maria
  • Date: 2013
  • Subjects: Fractions -- Study and teaching (Secondary) -- Namibia -- Case studies Percentage -- Study and teaching (Secondary) -- Namibia -- Case studies Mathematical notation -- Study and teaching (Secondary) -- Namibia Mathematics -- Study and teaching (Secondary) -- Namibia Experiential learning -- Namibia Education, Secondary -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1890 , http://hdl.handle.net/10962/d1006057
  • Description: The study examined the use of multiple representations such as the real world, written symbols, spoken symbols, diagrams and manipulatives by learners to promote the learning of percentages and fractions through social interaction. This investigation was carried out through a teaching and learning programme which was developed and implemented by me, the researcher. The effect of the implemented programme was the main focus of the research. The qualitative study was oriented in the interpretive paradigm – a paradigm that seeks to understand the meaning attached to human actions. Twenty learners participated in the implementation of the programme and 9 learners were selected for focus group interviews. The purpose of the interviews was to explore learners' understanding and feelings about the use of multiple representations in the learning of percentages and fractions through social interactions. The other tools employed in this study were pre-and-post diagnostic tests, observations, learners' work and a journal. The pre-test was used to determine learners' prior knowledge for the program design and implementation, while the post-test and learners' work were used to analyze the effect of the programme. Observations were used to investigate how multiple representations promoted or did not promote the learning of percentages and fractions. The teacher's journal was to record and reflect on any relevant information gathered on each lesson observed. The data shows that the effective use of multiple representations helped learners learn the concept of percentages and fractions better. Learners were able to look at representations in useful ways; multiple representations made some aspects of the concept clear; and multiple representations enabled learners to correct errors. Through the interaction between the teacher and learners, the following was found: all the learners changed words to change focus; learners made links between multiple representations; the learners deepened their concepts of percentages and fractions; learners could convert between fractions using multiple representations; learners could work out percentages of a quantity; and learners could express one quantity as a percentage of another. Furthermore, through the interaction between learners and learners all learners could identify more equivalent fractions of an initial fraction which was given to them; and they could increase and decrease a quantity by a given percentage. On the basis of this research, it can be concluded that the programme promoted the learning of percentages and fractions through three effective methodologies. The first methodology consisted of the effective use of multiple representations; the second methodology concerned the interaction between the teacher and learner during the learning process and the last methodology related to the interaction between the learners - interactions that were not strongly mediated by the teacher. I would recommend that teachers use these three effective approaches when teaching percentages and fractions to promote the learning of the concepts.
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  • Date Issued: 2013

An investigation on the stakeholders' perceptions of the involvement of the governing bodies in the appointment of teachers in the Libode District of the Eastern Cape Province

  • Authors: Mabunu, Sipho Christian
  • Date: 2013
  • Subjects: Teachers -- Recruiting -- School governing body -- Eastern Cape -- South Africa
  • Language: English
  • Type: Thesis , Masters , M Ed
  • Identifier: vital:18457 , http://hdl.handle.net/11260/d1008042
  • Description: Decentralization of governance is one of the many reforms that has been undertaken by the Department of Education in the Republic of South Africa since the attainment of democracy in 1994. The concept of decentralisation originates from the belief that the state alone cannot control schools, but should share its power with other stakeholders, particularly those closer to the school, on a partnership basis (Marishane, 1999:78). The South African Schools Act (SASA) No 84 of 1996 mandates the establishment of democratic structures of school governance in all schools (RSA, 1996a, section 16). According to the South African Schools Act No 84 of 1996, School Governing Bodies have been mandated to be responsible for the recommendation of teachers for appointment through interviews. This study was conducted in the Libode District in the Eastern Cape. Libode is composed of rural villages which are characterised by poverty, a high rate of unemployment and illiteracy. Many schools in the Libode district of education are experiencing problems emanating from the recruitment of teachers carried out by the SGBs. Interviews conducted by the SGBs are more often than not nullified and the selection and interview processes have to be repeated. They (SGBs) fail to defend their recommendations with valid facts when challenged by union representatives or by candidates themselves. The major concern of this study is to investigate the stakeholders' perceptions of the involvement of school governing bodies in the appointment of teachers in Libode district. A qualitative approach was employed for this research study. Purposive sampling was used for sampling the schools from which interviewees were selected. There were 14 respondents in the sample. Three (3) school principals , three teachers, three (3) teacher candidates, one SADTU teacher, one NAPTOSA teacher, two (2) SGB parents from the parent component and two (2) circuit managers were interviewed. The case study research design was employed to explore the perceptions of the stakeholders regarding teacher appointments. This research employed three data collection techniques, namely semi-structured interviews, documents analysis and observations. The main findings of this study reveal that the involvement, or participation, of the SGBs (parent components) in the recruitment of teachers is the source of conflict and disputes. The SGBs lack capacity, capacity to draft criteria for shortlisting qualified teachers, and capacity to conduct interviews properly and fairly. Findings suggest that problems still exist around SGBs' knowledge of Policies and Acts that enshrine procedures pertaining to teacher recruitment. In conclusion, from the findings, it appears premature for the system to mandate this professional function of teacher recruitment to the office of the SGBs.
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  • Date Issued: 2013

An operational model for increasing customer satisfaction for Detpak South Africa

  • Authors: Van Deventer, Reinard Gawie
  • Date: 2013
  • Subjects: Consumer satisfaction -- South Africa , Paper industry -- Customer services -- South Africa , Customer relations -- South Africa
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:8886 , http://hdl.handle.net/10948/d1020807
  • Description: Detpak South Africa is a subsidiary paper and board company of Mpact Limited, formally known as Mondi Packaging South Africa. The Mpact group of companies operates across 31 sites and employs more than 3 700 employees. Detpak South Africa specializes in three respective niche markets: international fast food packaging, industrial packaging and disposables packaging. The primary objective of this study is to propose an operational model for improving customer satisfaction levels within the disposables market for Detpak South Africa. Further, Detpak’s competitive position with respect to customer satisfaction was assessed and an empirical assessment was conducted to identify imperative attributes impacting on overall customer satisfaction. It is noted from marketing journals that providing a quality product at the right price no longer suffices as an adequate value proposition. Numerous authors have noted that there is no longer a difference between a goods market and a service market, in its purest form, and that manufacturers of goods must embrace the principles of service marketing to develop a competitive advantage within the market. A quantitative research was conducted to obtain data. The measuring instrument used to obtain data was a self-administered questionnaire. A total of 84 questionnaires were distributed nationally across South Africa. From the 84 questionnaires a total of 62 questionnaires were obtained from respondents, from which a final sample of n=59 was considered for capturing. Three questionnaires were excluded from the sample due to response error of non-completion. Correlation coefficient analysis was used to calculate the relationships between independent and dependant variables. It was found that all customer satisfaction attributes, listed below, had a positive relationship to overall customer satisfaction: Customer value; Product quality; Price; Communication; Reliability; Responsiveness; Customer service; Sales support. The hypothesized relationship between overall customer satisfaction and customer loyalty was measured and confirmed to be strongly positive. It can be concluded that a positive movement in overall customer satisfaction will be accompanied by a similarly positive movement in customer loyalty. Furthermore, through secondary review it was noted that the retention of existing customers costs much less and is more profitable than the acquisition of new business. The results presented within this study indicate a strong market position for Detpak South Africa in terms of product quality compared against competitive activity, which means a competitive advantage in the market for the company and which will assist in attaining its strategic objectives. The results also identified a number of customer satisfaction attributes which Detpak South Africa could improve to allow them to establish a firm position in the market through the overall improvement of customer satisfaction levels. Finally, an operational model integrating the important concepts identified within the literature study was proposed to assist Detpak South Africa in enhancing levels of perceived customer satisfaction. The model integrates the important business philosophies of customer relations, best practices, continuous improvement and, finally, customer satisfaction attributes.
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  • Date Issued: 2013

Analysis of factors influencing the performance of a hydrokinetic coil pump

  • Authors: Opperman, Adriaan Jacobus
  • Date: 2013
  • Subjects: Pumping machinery, Electric , Pumping machinery -- Performance
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:9640 , http://hdl.handle.net/10948/d1021041
  • Description: A hydrokinetic coil pump (HCP) is described by its name. It is a coil pump driven by the kinetic energy in flowing water. The hydrokinetic energy is converted into mechanical energy by means of a paddle-wheel. The coil pump makes up part of the paddle-wheel and together is called a HCP. The HCP floats in a stream of flowing water while tethered to the bank. The focus of the study was to identify and analyse the factors influencing the HCP. The HCP was then optimized for rural application. Data acquisition took place through experimentation on a full scale experimental platform according to a central composite experimental design. Variables used for the experimentation included; Stream Velocity, Delivery Head, Number of Coils, Discharge, Number of Paddles, Paddle-Wheel rotational speed Overall HCP efficiencies of up to 22 percent were obtained. The efficiency would drop as the stream velocity increased. Stream velocity has been identified as the most influential factor with regards to the variables analysed by this study. The HCP is ideal for rural application. The simplicity of the design ensures reliability as well as an effective water supply solution. The HCP is ideal for slow flowing rivers and can deliver up to 1190ℓ/h to a delivery head of 5m with a stream velocity of 1.2m/s. This is sufficient to supply a small rural community with running water.
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  • Date Issued: 2013

Analysis of ICT governance initiatives as a mechanism to enhance corporate governance, with particular reference to Nelson Mandela Bay Municipality

  • Authors: Tolom, Sindiswa
  • Date: 2013
  • Subjects: Corporate governance -- South Africa -- Nelson Mandela Bay Municipality , Information technology -- Management
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:8904 , http://hdl.handle.net/10948/d1020999
  • Description: Developing countries such as South Africa have a tremendous potential for rapid and sustainable economic and social development by leveraging the benefits and advantages of Information and Communication Technology (ICT) and applying it appropriately within the local government sector. As such, the Local Government Turnaround Strategy’s (LGTAS) vision states that: Each municipality must have the necessary ICT infrastructure and connectivity; and that ICT systems must be put in place across all municipalities to accelerate service delivery, and improve efficiency and accountability. However, technology on its own cannot achieve much; it must be supported by capable people and tested processes to provide services in which the public can have confidence. Disparities, both from within the municipal sector as well as in the larger South African ICT landscape, have influenced the manner in which municipalities make use of ICT. Nevertheless, it has been observed that despite the use of ICT, there has been a lack of utilising ICT governance to enhance corporate governance in the public sector, particularly in municipalities. In this study, an analysis was made of ICT governance initiatives, as a mechanism to enhance corporate governance, with particular reference to the Nelson Mandela Bay Municipality (NMBM) in the Eastern Cape. The research itself has identified risk levels that exist as a result of the lack of ICT governance and risk management. The respondents were given an opportunity to agree or disagree with statements regarding the state of ICT provision and support, corporate governance and other elements within the institution. The researcher has formulated recommendations to solve identified problem based in the research results in ICT governance and corporate governance. While governance developments have primarily been driven by the need for transparency regarding enterprise risks and the protection of shareholder value, the pervasive use of technology has created a critical dependency on ICT that calls for a specific focus on ICT governance. ICT governance is part of corporate governance,which is the responsibility of the organisation’s top executive, to ensure that its information technology supports the goals and objectives of the organisation, through a variety of structural mechanisms, processes and mechanisms for communication. Fundamentally, ICT governance is concerned with whether ICT is delivering value and the management of ICT risks, driven by a strategic alignment between business and ICT, resources management and performance management. The corporate governance of ICT involves evaluating and directing the plans for the use of ICT to support the Institution and monitoring these. It includes the strategy and policies for using ICT within the institution. The executive authority and executive management are accountable and responsible for ensuring that the governance of ICT is implemented in the institution in line with this framework.
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  • Date Issued: 2013

Analysis of official development assistance (ODA) in the Eastern Cape Province

  • Authors: Sotondoshe, Tolbert Hlanganisile
  • Date: 2013
  • Subjects: Economic assistance -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9202 , http://hdl.handle.net/10948/d1020422
  • Description: In this study Official Development Assistance (ODA) is defined as resource flows from international community in the form of grants, technical assistance, support and financial co-operation. Government is held partially responsible or accountable for the management of these resources but not accountable for utilization of direct support to NGOs and private sector. According to the National Treasury’s Official Development Assistance (ODA) 2010 Review Report, the Eastern Cape is the second largest recipient of ODA in relation to other provinces. The province of KwaZulu Natal, ranked number one, and the province of Limpopo was recorded as the third largest recipient of ODA. As such it is recorded that European Union is the greatest funder in the provincial government focusing in the areas of Health, Urban renewal and Local Economic Development source (National Treasury ODA 2010 Review Report). To date, no analysis has been done on ODA in the Eastern Cape. This study seeks to analyse Official Development Assistance in Eastern Cape with a view to identifying constraints and gaps that may be contributing towards the ineffectiveness of ODA in the Eastern Cape.
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  • Date Issued: 2013

Analysis of restricted earth fault relay application within a shunt capacitor bank design impacting on protection stability

  • Authors: Minkley, Warick
  • Date: 2013
  • Subjects: Electric power systems -- Protection , Electric power transmission -- Equipment and supplies -- Protection
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:9604 , http://hdl.handle.net/10948/d1021106
  • Description: This research is aimed at analyzing the performance of the restricted earth fault relay used on a 400kV capacitor bank scheme used on the Eskom Transmission network. After the commissioning of two Capacitor Banks using the above mentioned scheme design the plant was energized. As a result of the energization the Shunt Capacitor Bank (SCB) then experienced spurious trips. The cause of the trips was found to be the operation of the restricted earth fault relay. In this research project, restricted earth fault protection on SCBs in the Eskom Transmission environment will be the area of interest. The proposed research will analyze the current SCB protection scheme in service specifically looking at the restricted earth fault circuit design and relay performance. An equivalent model of the SCB from primary plant perspective based on theory will be derived. Recording and analyzing of Comtrade transient waveforms respectively, when the bank is nergized, will be done in order to provide a reference base to work from. Manual alculations of various parameters from the derived model including transient inrush currents and fault currents will be performed to access applicable scheme parameters. Further calculations will include the voltage setting for the restricted earth fault relay. As a result of the analysis a recommendation will be made on a viable solution or a revised design will be put forward, based on the results, to improve the scheme’s performance. The protection scheme is used on the two 400kV 100MVAR capacitor banks 11 and 12 at Hydra Substation.
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  • Date Issued: 2013

Analysis of temporal and spatial variations in water storage by means of gravimetric and hydrologic methods in the region around the South African gravimetric observation station

  • Authors: Mahed, Gaathier
  • Date: 2013
  • Subjects: Ground water -- South Africa , Geology -- South Africa , Hydrogeology -- South Africa , Water-supply -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/6714 , vital:21137
  • Description: This work examines the use of gravity data and its application to subsurface water reservoirs in the immediate vicinity of the South African Geodynamic Observatory, Sutherland (SAGOS), situated in a semi-arid region of the Karoo region of South Africa, and underlain by the Karoo sedimentary rocks intruded by dolerite dykes and sills. SAGOS houses the only supergravity metre (SG) in Africa, and this thesis sets out to test its use in monitoring groundwater dynamics using hydrological and gravity data. The main aim of this work is the application of the SG data, in conjunction with hydrological data, to better understand episodic recharge of subsurface reservoirs. The importance of water as a resource, globally and specifically the Karoo, is reviewed in conjunction with supply and demand of water. This is to contextualise the socio-economic, technical as well as policy issues related to water resource management. Applicable technologies for water resource management and efficient water use are highlighted and the application of gravity to hydrology is introduced, including satellite as well as ground based tools. In addition, arid zone hydrology as well as recharge and its mechanisms are analysed in order to better understand these processes when examined from gravity measurements. Issues related to understanding flow within the vadose zone as well as in secondary aquifers are examined, and gravity residuals and subsurface hydrology are highlighted. Thereafter, a conceptual groundwater flow modelof the study area is developed using multiple tools. First, the geology around SAGOS was mapped using SPOT 5 imagery and then ground truthed. Second, stable isotopes and water chemistry analysis was undertaken on water samples from selected boreholes. The results allude to preferential flow acting as the main mechanism for groundwater recharge. Follow-up pump-tests illustrate that fracture connectivity is greatest at close proximity to the dyke. Soil mapping, using aerial photography was also undertaken. Duplex soils, enriched with clay at depth, dominate the study area. Using in-situ infiltration tests, it is shown that the alluvium, which lines the river beds, has a higher hydraulic conductivity than the other soils, confirming that these streams act as preferential conduits for subsurface recharge. Precipitation events were correlated against gravity residuals at 4 wells, over different time periods. The results are examined using time series analyses. Gravity residuals from well SA BK07, over a period of 24 hours after the rainfall event, delineate instances of negative correlations, as well as strong positive correlations (of up to 0.9). On the whole however, correlations between gravity and groundwater at SA BK07 are variable and weak, and in conjunction with water level measurements and water chemistry, the data suggest that this well is located in a dynamic conduit (throughflow) and not in a permanent groundwater reservoir. By contrast, other wells show strong positive correlations between gravity residuals and water levels following episodic recharge events for a later time series. Correlations between the water levels and gravity residuals in wells SA BK04, SA BK05 and SA BK 01 are in excess of 0.7 for specific rainfall events. In summary, the results suggests that gravity is an excellent tool for measuring episodic groundwater recharge within the immediate vicinity of the SAGOS. This implies that gravity can aid in monitoring groundwater losses/gains in arid and semi-arid areas. Recommendations for future work are highlighted at the end; these include the possible use of hydrological modelling of reservoirs at various scales and then comparing these results to the SG as well as GOCE and GRACE satellites data, and then improving numerical modelling of the groundwater dynamics for sites like Sutherland and the surrounding arid Karoo region, where sparse water shortages, and potential pollution related to fracking for shale-gas, are likely to compete with established water needs for farming and human consumption. It is also suggested that the gravity modelling be examined to better understand site specific scenarios and thus aid in improving the processing of the gravity signal.
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  • Date Issued: 2013

Analysis of the implementation of corporate level strategy in a South Afircan furniture retailer

  • Authors: Nkatsha, Thembinkosi Sydney
  • Date: 2013
  • Subjects: Reengineering (Management) , Consolidation and merger of corporations -- South Africa -- Case studies , Organizational change -- Management
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:856 , http://hdl.handle.net/10962/d1018272
  • Description: [Integrative Summary] This study is situated in the complex field of change management, and strategy execution. The study focuses on the corporate level restructuring of Ellerine Holdings Limited (EHL), subsequent to its acquisition by the micro lending financial institution African Bank Investments Limited (ABIL). The interest of the researcher was aroused by the uniqueness of the relationship. This was the first of its kind in a South African context, where a banker owned a furniture retailer. The restructuring was undertaken shortly after the acquisition. This research paper adopted a case study approach, in describing the restructuring initiative that took place in EHL, focusing on the period between January 2008 and the end of 2010/ 11 financial year on the 30th of September 2011. The case captures the significant phases of the restructuring including a background of (1) the protagonist, Toni Fourie (Chief Executive Officer), (2) EHL as the researched company, (3) the industry it operates in, and (4) the case content. Brief teaching notes have been provided to explain the teaching value of the case and to assist with its delivery in the classroom. Attention is drawn to a presentation by the protagonist in November 2011, named 'A CEO Insight' where he gave an overview and insights of the road travelled in restructuring Ellerine Holdings Limited, and more importantly highlights the following about the purpose and nature of the restructuring of the organisation. • A plan to change the way the industry works. • The creation of a profitable, stand-alone retail business through: o The sale of two companies, the closure of two companies and consolidating from thirteen to six brands. o Separating financial services from retail. o Moving the financial services component to African Bank, also a subsidiary of ABIL. o Redesigning the credit model. o Completion of twelve system changes. • Over R600million reduction in cost • A place where people want to work. The restructuring outlined above represents a major shake-up in many aspects of the corporation. The main challenge for Toni Fourie and his team was: how best could they restructure EHL to extract synergies between their two subsidiaries Ellerine Holdings Limited & African Bank to increase shareholders ' value at Group level. The case seeks to describe this in detail. The overarching strategy underpinning the restructuring of the researched corporation is premised on the price volume elasticity equation, by reducing the cost of credit, thereby driving pricing down within the brands, and facilitating more people having access to affordable credit. The case study of the restructuring is presented in Section 1. A review of relevant literature on strategy implementation is presented in Section 2, focusing on restructuring. Successful implementation of strategies only takes place with structures that are developed by organisations to support the achievement of their strategic objectives. Organisational architecture and design have a critical role to play in the execution of organisational strategies. Nadler and Tushman (1978) emphasise the importance of congruence in the organisational design, for the organization to not only deliver superior results but to sustain them over a period of time. Research by Okumus (2005) seems to tell us that the lack of credible framework to implement strategy, has contributed the high failure rate of strategy initiatives. Although this is a strategy implementation case, it also touches on aspects of leadership - mainly the architectural role - and the role, or influence of strategic leadership, in restructuring the corporation. The results of this research paper were achieved by following a specific research methodology. The aim of the research was to analyse the restructuring of the researched company at corporate level, having the following objectives in mind; • Understanding the strategy. • Analysing the design decisions in the light of the strategy chosen by the top management of Ellerine Holdings Limited. • Analysing what monitoring and control measures had been designed to facilitate the corporate restructuring. Data was collected through documentation of the corporation that was made available to the researcher on request, as well as those that are in the public domain, and an interview with the CEO of the researched company. The interview was conducted after analysing the documentation (Hakim, 2000). The Methodology is detailed in Section 3. The researcher hopes that the case study will contribute to learning about business leadership and strategic management. The case should develop an understanding of the complexities related to strategy execution at corporate level, particularly the restructuring aspect of it.
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  • Date Issued: 2013

Analysis of the influence of peer education programmes on learner behaviour, the case of Bulelani high school, Queenstown

  • Authors: Bedula, Nomanani Doris
  • Date: 2013
  • Language: English
  • Type: Thesis , Masters , MPA
  • Identifier: http://hdl.handle.net/10353/1165 , vital:26532
  • Description: This study focuses on the influence of peer education programmes on learner behaviour. Peer education is a critical approach for behaviour-change. The presentation had two objectives. The first objective was to determine the nature and extent of peer education programmes policy implementation in the school under study. The second objective was to determine the impact of the policy on learner behaviour. A questionnaire which was administered to all trained peer educators at Bulelani High School indicated that all respondents agreed that peer education was educationally relevant and offered accurate information. Furthermore, results indicated that older learners strongly agreed that peer education programmes have an impact on behavioural changes than younger learners who merely agreed on that. The results also showed that the duration of involvement in peer education programmes influences the opinion on the impact of peer education on behavioural changes. Looking at the respondents ’gender, the researcher could not find any evidence that the impact of peer education on behavioural change depends on the gender of the respondent and therefore concludes that opinions are independent of gender. The study shows that in schools where peer education programmes are well implemented and monitored, they do impact on learner-behaviour in a positive way.
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  • Date Issued: 2013

Anchovy and Sardine in Algoa Bay and their relationship with response variables in two threatened avian predators

  • Authors: Potter, Cara-Paige
  • Date: 2013
  • Subjects: Fishes -- Predators of -- South Africa -- Algoa Bay , Anchovies -- South Africa , Sardines -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10730 , http://hdl.handle.net/10948/d1021130
  • Description: Huge populations of sardine and anchovy exist in the four major upwelling systems around the world. These fish are both important ecologically and economically. Pelagic fish dominate the mid trophic level and can exert both a top-down control of zooplankton and a bottom-up control on predatory fish and marine top predators. They also make up a substantial contribution of the world catches in seas around the world where they co-exist in upwelling areas. The fluctuations of sardine and anchovy are largely influenced by recruitment from the larval stage and by the physical environmental forces that determine the planktonic compositions upon which they feed. In southern Africa, the biology and behaviour of two threatened seabird species, African penguins (Spheniscus demersus) and Cape gannets (Morus capensis), are directly influenced by the availability of sardine (Sardinops sagax) and anchovy (Engraulis encrasicolus). This study aimed to provide further insight into the fluctuations of sardine and anchovy in relation to the variability of environmental factors such as wind, sea surface temperature, rainfall and plankton abundance, focusing specifically on Algoa Bay in the Eastern Cape, South Africa. Algoa Bay is particularly important as it is home to the world’s largest African penguin colony and the world’s largest gannetry. Therefore, to further investigate the populations of these two seabird species, the fluctuations of their food source were studied.
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  • Date Issued: 2013

Antifugal evaluation and phytochemical analysis of selected medicinal plants used in the treatment of fungal diseases associated with HIV infection in the Eastern Cape Province, South Africa

  • Authors: Mbeng, Wilfred Otang
  • Date: 2013
  • Subjects: Medicinal plants -- ethnobotanical survey , Opportunistic fungal infections , HIV/AIDS -- Cytotoxicity , Eastern Cape -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD (Botany)
  • Identifier: vital:11307 , http://hdl.handle.net/10353/d1006834 , Medicinal plants -- ethnobotanical survey , Opportunistic fungal infections , HIV/AIDS -- Cytotoxicity , Eastern Cape -- South Africa
  • Description: Background. As a result of the AIDS pandemic, many people areimmuno compromised andopportunistic fungal infections (OFIs) such as candidiasis are common. Despite the widespread use of medicinal plants in South Africa, there is a dearth of knowledge regarding the use of such plants in the management of these infections. This study evaluates three South African medicinal plants (Arctotis arctotoides, Pittosporum viridiflorum, and Gasteria bicolor) traditionally used in the treatment of OFIs in HIV/AIDS patients, in the Eastern Cape Province, South Africa. Materials and methods. A six-stage process of documentation, evaluation and analysis of results was conducted: (1) Selection of medicinal plants most frequently used in the treatment of OFIs through ethnomedical studies and the survey of specialised literature; (2) Collection and preparation of the extract of each plant; (3) Antifungal evaluation of the crude plant extracts. (4) Phytochemical and antioxidant evaluation of the active crude plant extracts; (5) Cytotoxicity evaluation of the bioactive extracts using the Chang liver cell line, and (6) Statistical analysis of the results. Ethnobotanical information was obtained through interviews with traditional healers and AIDS patients with the aid of semi-structured questionnaires, direct observations and by reviewing studies reported in the literature. Following the approval from the University of Fort Hare‘s Ethics Committee, 101 HIV/AIDS patients were recruited through convenience sampling into an anonymous cross-sectional questionnaire study. The agar diffusion and micro-dilution methods were used to determine the antifungal activities of the hexane, acetone and aqueous extracts of A. arctotoides, G. bicolor and P. viridiflorum against 10 opportunistic fungi.
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  • Date Issued: 2013

Antimicrobial activities of three medicinal plants against selected diarrheagenic pathogens

  • Authors: Nkosi, Themba Johan
  • Date: 2013
  • Subjects: Anti-infective agents , Drug resistance in microorganisms , Materia medica, Vegetable
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:10126 , http://hdl.handle.net/10948/d1020759
  • Description: Diarrhea is a global concern that the United Nations Children’s Fund (UNICEF) and the World Health Organization (WHO), have confirmed to be the second major cause of death in children under the age of five. Major bacterial pathogens that cause diarrhea include Escherichia coli, Salmonella species, Shigella species and Staphylococcus aureus. Antibiotic therapy is recommended depending on the severity and presentation of the disease; however, the appearance of antibiotic-resistant bacteria is an emerging global threat to the ability to treat these bacterial infections. This situation could be overcome by the discovery of new natural antibiotics. Plants have been a source of medicine for centuries and have been used to treat diseases including diarrhea. This makes plants a natural potential target to study for their antibiotic properties. The objective of this study was to determine the antibiotic properties of medicinal plants against known pathogens that cause bacterial diarrhea. Three medicinal plants, Cassia abbreviata, Kigelia africana, and Geranium incanum were investigated for their antimicrobial properties against these strains of microorganisms: American Type Culture Collection (ATTC) and Clinical Strains (CS). The plant materials were ground into powder, which was then dissolved in methanol, acetone and distilled water to extract the active compounds. The plant extracts were then used to (i) determine their antibiotic activity, (ii) determine the minimum inhibitory concentration (MICs), (iii) analyze the thin layer chromatography (TLC) fingerprints, and (iv) analyze the autobiography assay. The results obtained in this study met the aim and objectives of this study. The antimicrobial activities of the selected plants were obtained as discussed in Chapter 2 and 3. These results indicated that the traditional plants could be used as antimicrobials. In the screening assays, the test microorganisms were inhibited by the plant extracts, when they were subjected to plant extracts. This was performed on Mueller Hinton agar as sensitivity testing, which revealed clear zones of inhibition. The MIC values for each plant extract were established which ranged from 0.101 to 13.3 mg/dl. The TLC analysis revealed the spots which contained the active compounds which inhibited the bacterial growth. A bioautography assay was performed on the TLC plates, which exposed the exact spots containing the active compound inhibiting the bacteria. These results are clearly consistent with what former scientists have observed. Detailed explanations on the results are in Chapter 3 and 4 of this paper. It is important to note that all the procedures performed in this study were in vitro assays. Some effective in vitro assay activity may not always result in the same effective in vivo activity, because some active compounds may be metabolized and degraded into inactive metabolites. For this reason, the in vitro results obtained in this study, may not reflect the true effectiveness of the compounds in in vivo trials. It is therefore advised that future scientists should take a step further in analyzing the plant extracts through in vivo assays. Further testing and study on these plants at an advanced molecular level will be beneficial in the medical fields in the search for new antibiotics to treat infectious diseases. Purification and further analysis of their products can be helpful in the production of pure natural medicines. This will discover the active ingredients and compounds responsible for inhibition of the microorganisms. This will make the compounds potential candidates for a scientific validation and analysis for future scientists to bring a new dawn in the fight against infectious diseases.
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  • Date Issued: 2013

Application of assisted reproduction technologies on the indigenous Nguni cows and heifers

  • Authors: Maqhashu, Ayanda
  • Date: 2013
  • Language: English
  • Type: Thesis , Masters , MSc Agric (Animal Science)
  • Identifier: vital:11828 , http://hdl.handle.net/10353/d1016096
  • Description: The aims of the study were to compare superovulatory (SO) response rate and embryo quality recovered; consequently, correlate sperm motility with fertilization rate on superovulated stud Nguni cows and heifers. Furthermore, compare oestrous synchronization response and pregnancy rate of three breed type cows (Brahman, Bonsmara and Nguni) of different body condition scores following timed artificial insemination in KwaZulu-Natal (KZN) and Limpopo provinces. Nguni stud cows (n= 15) and heifers (n= 10) aged 4-6 and 2-3 years were used as embryo donors. Superovulation of donors involved insertion of a controlled internal drug release device (CIDR) and two injections of FSH daily 12 hours apart for 4 days on a decreasing dosage. Fresh Nguni semen was collected from proven Nguni stud bulls and assessed by computer aided sperm analysis (CASA) before artificial insemination (AI). The doses of AI were prepared and conducted twice, 12 hours apart on synchronized and superovulated Nguni cows or heifers. Embryos were flushed 7 days after AI using a non-surgical technique. Embryos were immediately evaluated under stereo microscope and classified according IETS standard codes (C1, C1- and C2). All transferrable embryos were vitrified. Two pilot study sites were chosen in Eastern Cape – Great kei; (n= 5) and Limpopo - Vuvha; (n=5) provinces for Embryo transfer. Each recipient cow was implanted with one frozen-thawed embryo. For oestrous synchronization, cows (Braman, Bonsmara and Nguni type) were selected in different villages, regardless of parity, age, breed and body weight following pregnancy diagnosis. Cows were grouped according to breed type and body condition scores (BCS) on a scale of 1-5. Group 1 had BCS of ≤ 2.5 in KwaZulu-Natal (n=81) and Limpopo n=71), Group 2 had BCS of ≥ 3 in KwaZulu-Natal (n=79) and Limpopo (n=100) cows. Cows were synchronized by inserting the controlled intravaginal drug release (CIDR) and removed on Day 8, followed by administration of prostaglandin. The white heat mount detectors (HMD) were placed on the individual cow’s tail head as an indicator for oestrous response if colour changed to red and inseminated twice at 12 hours interval. Pregnancy diagnosis was performed by an ultra sound scanner and rectal palpation 90 days after TAI in embryos and semen recipient cows. There was no significant difference on the superovulatory response rate between Nguni cows (40%) and heifers (40%). There was a significant difference on the ovary reaction (number of corpus luteum) of cows (11.33±1.41) and heifers (4.00±0.57). There were no significant differences observed on the embryo quality between Nguni cows (2.5±1.00 and 1.25±0.59) and heifers (0.83±0.41 and 1.00±0.36) for excellent (C1) and good (C1-). However, cows had more numbers of unfertilized ova (5.5±1.05 and 1.75±0.47) and degenerate embryos (3.66±1.00 and 1.25±0.39) than heifers. Village cows responded to oestrous synchronization successfully in KZN (100%) and Limpopo (99%) regardless of body conditions and breed type. The lowest pregnancy rate was recorded in Brahman and Bonsmara type cows with BCS of ≤ 2.5 regardless of Province. Interestingly, Nguni type cows with same body condition of ≤ 2.5 had higher average pregnancy rate of 59.5% in Limpopo and 53.5% in KZN. However, cows with BCS of ≥3 had better pregnancy rate regardless of cow breed type, and province. In conclusion, only 40% of both Nguni cows and heifers responded to superovulation. However, Nguni cows had better ovaries reaction compared to heifers. The quality of embryos recovered was similar for both Nguni cows and heifers. Moreover, there was a positive correlation between total sperm motility and fertilization rate bull 1 (93.7%) inseminated the cows (67.5%) and bull 2 (83.5%) inseminated the heifers (53.5%). Higher pregnancy rate (60%) was recorded in Limpopo compared to Eastern Cape (0%). Interestingly, more than 99% of village cows responded to synchronization and inseminated with frozen-thawed semen successfully. Village Nguni type cows were not affected by body condition scoring as they had higher and similar pregnancy rate as those that had body condition of ≥ 3. It is suggested that it is not advisable to breed synchronized Brahman and Bonsmara type cows with the body condition of ≤ 2.5 except in Nguni cow type as more than 57% average pregnancy rate was achieved.
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  • Date Issued: 2013

Application of bidentate N,N'-donor extractants in the hydrometallurgical separation of base metals from an acidic sulfate medium

  • Authors: Okewole, Adeleye Ishola
  • Date: 2013
  • Subjects: Hydrometallurgy Sulfates Nanofibers Electrospinning Sorbents Extraction (Chemistry) Solvent extraction Stereochemistry
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4281 , http://hdl.handle.net/10962/d1002610
  • Description: Bidentate imidazole-based extractants, 1-octylimidazole-2-aldoxime (OIMOX) and 1-octyl-2-(2′-pyridyl)imidazole (OPIM), along with dinonylnaphthalene sulfonic acid (DNNSA) as a synergist, were investigated as potential selective extractants for Cu²⁺and Ni²⁺ respectively from base metals in a solvent extraction system. The study was extended to evaluate the sorption and separation of Ni²⁺ from other base metals in a solid-solution system using microspherical Merrifield resins and nanofibers functionalized with 2,2′-pyridylimidazole. Copper was effectively separated with OIMOX and DNNSA as extractants from nickel with ΔpH½ ≈1.05 and the extraction order of Cu²⁺ > Ni²⁺ > Zn²⁺ > Cd²⁺> Co²⁺ was achieved as a function of pH. At pH 1.65 the extracted copper, from a synthetic mixture of the base metals reached 90.13(±0.90)%, and through a two-step extraction process 98.22(±0.29)% copper was recovered with negligible nickel and cobalt impurities. Stripping of the copper from the loaded organic phase using TraceSelect sulphuric acid at pH 0.35 yielded 96.60(±0.44)% of the loaded quantity after the second stage of stripping. The separation of Ni²⁺ from the borderline and hard acids; Co²⁺, Cu²⁺, Zn²⁺, Fe2²⁺, Fe²⁺, Mn²⁺, Mg2²⁺ and Ca²⁺ at a pH range of 0.5-3.5 with OPIM and DNNSA was acvieved to the tune of a ΔpH½≈ 1.6 with respect to cobalt from a sulfate and sulfate/chloride media. A three-stage counter-current extraction of Ni²⁺, at the optimized pH of 1.89, from a synthetic mixture of Ni²⁺, Co²⁺ and Cu²⁺, yielded 99.01(±1.79)%. The total co-extracted Cu²⁺ was 48.72(±0.24)% of the original quantity in the mixture, and it was 19.85(±0.28%) for Co²⁺. The co-extracted Cu²⁺ was scrubbed off from the loaded organic phase at pH≈8.5 by using an ammonium buffer, while co-extracted Co²⁺ was selectively and quantitatively stripped with H₂SO₄ at pH 1.64. The total recovery of Ni²⁺ by stripping at pH 0.32 was 94.05(±1.70)%. In the solid-liquid system, Ni²⁺ was separated from Co²⁺, Cu²⁺, and Fe²⁺ with the microspherical resins funtionalised with 2,2′-pyridylimidazole by a separation factor (β) in the range 22-45. Electrospun nanofibers as sorbents yielded high sorption capacity in the range of 0.97 - 1.45 mmol.g⁻¹ for the same metals ions. Thus, 1-octylimidazole-2-aldoxime (OIMOX), and1-octyl-2-(2′-pyridyl)imidazole (OPIM) can be effectively utilized alongside DNNSA as a co-extractant in the separation of Cu²⁺ and Ni²⁺ respectively from base metals in acidic sulfate medium in a solvent extraction process, and the latter as a selective ligand in the solid-liquid separation of Ni²⁺ from Co²⁺, Cu²⁺, and Fe²⁺.
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  • Date Issued: 2013
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