The E.coli RNA degradosome analysis of molecular chaperones and enolase
- Authors: Burger, Adélle
- Date: 2010
- Subjects: Molecular chaperones , Escherichia coli -- Biotechnology , Polyphosphates , Polyphosphates -- Biotechnology , RNA-protein interactions
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3950 , http://hdl.handle.net/10962/d1004009 , Molecular chaperones , Escherichia coli -- Biotechnology , Polyphosphates , Polyphosphates -- Biotechnology , RNA-protein interactions
- Description: Normal mRNA turnover is essential for genetic regulation within cells. The E. coli RNA degradosome, a large multi-component protein complex which originates through specific protein interactions, has been referred to as the “RNA decay machine” and is responsible for mRNA turnover. The degradosome functions to process RNA and its key components have been identified. The scaffold protein is RNase E and it tethers the degradosome to the cytoplasmic membrane. Polynucleotide phosphorylase (PNPase), ATP-dependent RNA helicase (RhlB helicase) and the glycolytic enzyme enolase associate with RNase E to form the degradosome. Polyphosphate kinase associates with the degradosome in substoichiometric amounts, as do the molecular chaperones DnaK and GroEL. The role of DnaK as well as that of enolase in the RNA degradosome is unknown. Very limited research has been conducted on the components of the RNA degradosome under conditions of stress. The aim of this study was to understand the role played by enolase in the assembly of the degradosome under conditions of stress, as well as investigating the protein levels of molecular chaperones under these conditions. The RNA degradosome was successfully purified through its scaffold protein using nickel-affinity chromatography. In vivo studies were performed to investigate the protein levels of DnaK and GroEL present in the degradosome under conditions of heat stress, and whether GroEL could functionally replace DnaK in the degradosome. To investigate the recruitment of enolase to the degradosome under heat stress, a subcellular fractionation was performed to determine the localization of enolase upon heat shock in vivo. The elevated temperature resulted in an increased concentration of enolase in the membrane fraction. To determine whether there is an interaction between enolase and DnaK, enolase activity assays were conducted in vitro. The effect of DnaK on enolase activity was measured upon quantifying DnaK and adding it to the enolase assays. For the first time it was observed that the activity of enolase increased with the addition of substoichiometric amounts of DnaK. This indicates that DnaK may be interacting with the RNA degradosome via enolase.
- Full Text:
- Date Issued: 2010
- Authors: Burger, Adélle
- Date: 2010
- Subjects: Molecular chaperones , Escherichia coli -- Biotechnology , Polyphosphates , Polyphosphates -- Biotechnology , RNA-protein interactions
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3950 , http://hdl.handle.net/10962/d1004009 , Molecular chaperones , Escherichia coli -- Biotechnology , Polyphosphates , Polyphosphates -- Biotechnology , RNA-protein interactions
- Description: Normal mRNA turnover is essential for genetic regulation within cells. The E. coli RNA degradosome, a large multi-component protein complex which originates through specific protein interactions, has been referred to as the “RNA decay machine” and is responsible for mRNA turnover. The degradosome functions to process RNA and its key components have been identified. The scaffold protein is RNase E and it tethers the degradosome to the cytoplasmic membrane. Polynucleotide phosphorylase (PNPase), ATP-dependent RNA helicase (RhlB helicase) and the glycolytic enzyme enolase associate with RNase E to form the degradosome. Polyphosphate kinase associates with the degradosome in substoichiometric amounts, as do the molecular chaperones DnaK and GroEL. The role of DnaK as well as that of enolase in the RNA degradosome is unknown. Very limited research has been conducted on the components of the RNA degradosome under conditions of stress. The aim of this study was to understand the role played by enolase in the assembly of the degradosome under conditions of stress, as well as investigating the protein levels of molecular chaperones under these conditions. The RNA degradosome was successfully purified through its scaffold protein using nickel-affinity chromatography. In vivo studies were performed to investigate the protein levels of DnaK and GroEL present in the degradosome under conditions of heat stress, and whether GroEL could functionally replace DnaK in the degradosome. To investigate the recruitment of enolase to the degradosome under heat stress, a subcellular fractionation was performed to determine the localization of enolase upon heat shock in vivo. The elevated temperature resulted in an increased concentration of enolase in the membrane fraction. To determine whether there is an interaction between enolase and DnaK, enolase activity assays were conducted in vitro. The effect of DnaK on enolase activity was measured upon quantifying DnaK and adding it to the enolase assays. For the first time it was observed that the activity of enolase increased with the addition of substoichiometric amounts of DnaK. This indicates that DnaK may be interacting with the RNA degradosome via enolase.
- Full Text:
- Date Issued: 2010
Isomorphism, institutional entrepreneurship and total quality management (TQM) : a case study in the implementation of quality management standards and excellence models in South African developmental local government
- Authors: Naidoo, Pravine
- Date: 2010
- Subjects: Local government -- South Africa -- Eastern Cape Political entrepreneurship -- South Africa -- Eastern Cape Total quality management Municipal services -- South Africa -- Eastern Cape -- Management Municipal services -- Customer services -- South Africa -- Eastern Cape Political leadership -- South Africa -- Eastern Cape Organizational effectiveness
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1193 , http://hdl.handle.net/10962/d1007141
- Description: Within the new constitutional order, South African local government has been afforded specific status and is protected as a distinctive sphere of government in terms of the Constitution Act 108 of 1996. Municipalities are no longer a mere function of national or provincial governments. In addition to this entrenched status, the Constitution and other developmental local government legislation vests local government with specific functions and responsibilities as part of the process of building a new democracy and promoting socio-economic development and upliftment. Consequently, local government managers are under constant pressure to improve the performance and quality of service delivery. They are expected to satisfy a number of stakeholders, achieve increases in efficiency, as well as attain developmental service delivery goals as contained in their Integrated Development Plan (IDP). Quality management standards and excellence models in support of the total quality management (TQM) philosophy are relatively new public management approaches that changes traditional organisational decision-making practices to deliver services to its customers in more effective and efficient ways. In essence, quality management standards and excellence models are performance management methodological practices, techniques and tools designed to meet and exceed public requirements. It accomplishes this through determining what constitutes excellence in customer service, and then empowering employees to a never-ending search for quality improvement in the delivery of services, in terms of the continuous improvement and continuous process improvement philosophies, of which total quality management (TQM) is premised on. Consequently, quality management standards and excellence models (such as the ISO 9001: 2008 QMS, ISO 14001: 2004 EMS, EFQM and SAEF Excellence Models) as methodological practices, techniques or tools in support of the critical factors (CFs) of the total quality management (TQM) philosophy, namely: (1) customer-based approach, (2) senior management commitment and leadership, (3) quality planning, (4) management based on facts, (5) continuous improvement, (6) involvement of all members of the organisation, (7) education and training, (8) teamwork, (9) communication systems, (10) learning, (11) process management, (12) co-operation with suppliers, and (13) organisational awareness and concern for the social and environmental context, can provide a framework by which to achieve the goals of effective and efficient service delivery in developmental local government, as they foster a culture of performance and accountability. Local government managers could use these quality and excellence methodological practices, techniques and tools, as a starting point to improve efficiencies in their municipalities, as the programmes afford them an opportunity to systematically evaluate the municipality and determine what leads to organisational success and deliverables. Institutional theory suggests that organisations are both influenced by and can influence the society in which they operate. Institutional theorists believe that the motivation for a change in internal practices might not only be performance related, but may primarily be to enhance or maintain the legitimacy of the respective institution. Institutional theory also focuses on the social contract that exists between the institution and society. This social contract is believed to represent the expectations of society. From an institutional point of view, it has been suggested that institutions may change and adopt the norms of society to appear legitimate to that society. This infers that when societal norms and values change, institutions will be expected to change. These societal pressures combined with legislative changes, require institutional entrepreneurs to respond to these isomorphic pressures, and will work to preserve the institution's legitimacy by incorporating, or at least appearing to incorporate, new practices, norms and values. The aim of this research study was to analyse within an institutional theory framework, the implementation of quality management standards and excellence models in support of the total quality management (TQM) philosophy and developmental local government within two South African municipalities. The research investigation has been undertaken within the social constructionist paradigm and using the case study method. Interviews and documents were the data sources and thematic analysis was used as a tool to analyse the data by applying a theory-driven coding procedure. The findings from the two research sites, namely Makana Municipality in Grahamstown and Drakenstein Municipality in Paarl reveal that the implementation of quality management standards and excellence models in support of the total quality management (TQM) philosophy in both municipalities was not a smooth process and there were many challenges such as political instability, lack of commitment on the part of the senior leadership and management, staff and skills shortages, resistance by staff to implementation and resource constraints. Institutional theory has proved to be useful in understanding why the Makana and Drakenstein Municipalities implemented quality management standards and excellence models. Because of coercive, mimetic and normative isomorphic pressures affecting the Makana and Drakenstein municipalities, change was imperative if these institutions were to remain relevant and legitimate in order to address its service delivery mandate of effectiveness and efficiency. Institutional theory provided a theoretical lens to understand and appreciate the pressures that affected the municipalities because of its new developmental mandate as encapsulated in new municipal legislation. It also assisted in understanding how institutional entrepreneurs responded to these pressures to conform. The implementation of quality management standards and excellence models in the Makana and Drakenstein municipalities was adversely affected by volatility amongst the political leadership of both municipalities. The successful implementation of these standards and models would require collective action from the political, bureaucratic and procedural entrepreneurs in order to enhance effective, efficient and accountable service delivery. However, in both the Makana and Drakenstein municipalities, institutional entrepreneurs, namely councillors and officials were not working together as a collective to implement quality management standards and excellence models. Evidence has shown that the absence of stable political leadership and noncooperation and collaboration amongst institutional entrepreneurs contributed significantly to the non-institutionalisation of quality management standards and excellence models in these Municipalities. This implies that legitimacy has not been achieved, due to institutional entrepreneurs not collaborating and collectively working with each other to implement the quality management standards and excellence models. Thus, this research study suggests that the strategic and collective role of the political and administrative leadership as institutional entrepreneurs is critical if the municipality is to achieve its aims and objectives, namely effective, efficient, and accountable service delivery in developmental local government. Recommendations in respect of future research and to practitioners have also been offered.
- Full Text:
- Date Issued: 2010
- Authors: Naidoo, Pravine
- Date: 2010
- Subjects: Local government -- South Africa -- Eastern Cape Political entrepreneurship -- South Africa -- Eastern Cape Total quality management Municipal services -- South Africa -- Eastern Cape -- Management Municipal services -- Customer services -- South Africa -- Eastern Cape Political leadership -- South Africa -- Eastern Cape Organizational effectiveness
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1193 , http://hdl.handle.net/10962/d1007141
- Description: Within the new constitutional order, South African local government has been afforded specific status and is protected as a distinctive sphere of government in terms of the Constitution Act 108 of 1996. Municipalities are no longer a mere function of national or provincial governments. In addition to this entrenched status, the Constitution and other developmental local government legislation vests local government with specific functions and responsibilities as part of the process of building a new democracy and promoting socio-economic development and upliftment. Consequently, local government managers are under constant pressure to improve the performance and quality of service delivery. They are expected to satisfy a number of stakeholders, achieve increases in efficiency, as well as attain developmental service delivery goals as contained in their Integrated Development Plan (IDP). Quality management standards and excellence models in support of the total quality management (TQM) philosophy are relatively new public management approaches that changes traditional organisational decision-making practices to deliver services to its customers in more effective and efficient ways. In essence, quality management standards and excellence models are performance management methodological practices, techniques and tools designed to meet and exceed public requirements. It accomplishes this through determining what constitutes excellence in customer service, and then empowering employees to a never-ending search for quality improvement in the delivery of services, in terms of the continuous improvement and continuous process improvement philosophies, of which total quality management (TQM) is premised on. Consequently, quality management standards and excellence models (such as the ISO 9001: 2008 QMS, ISO 14001: 2004 EMS, EFQM and SAEF Excellence Models) as methodological practices, techniques or tools in support of the critical factors (CFs) of the total quality management (TQM) philosophy, namely: (1) customer-based approach, (2) senior management commitment and leadership, (3) quality planning, (4) management based on facts, (5) continuous improvement, (6) involvement of all members of the organisation, (7) education and training, (8) teamwork, (9) communication systems, (10) learning, (11) process management, (12) co-operation with suppliers, and (13) organisational awareness and concern for the social and environmental context, can provide a framework by which to achieve the goals of effective and efficient service delivery in developmental local government, as they foster a culture of performance and accountability. Local government managers could use these quality and excellence methodological practices, techniques and tools, as a starting point to improve efficiencies in their municipalities, as the programmes afford them an opportunity to systematically evaluate the municipality and determine what leads to organisational success and deliverables. Institutional theory suggests that organisations are both influenced by and can influence the society in which they operate. Institutional theorists believe that the motivation for a change in internal practices might not only be performance related, but may primarily be to enhance or maintain the legitimacy of the respective institution. Institutional theory also focuses on the social contract that exists between the institution and society. This social contract is believed to represent the expectations of society. From an institutional point of view, it has been suggested that institutions may change and adopt the norms of society to appear legitimate to that society. This infers that when societal norms and values change, institutions will be expected to change. These societal pressures combined with legislative changes, require institutional entrepreneurs to respond to these isomorphic pressures, and will work to preserve the institution's legitimacy by incorporating, or at least appearing to incorporate, new practices, norms and values. The aim of this research study was to analyse within an institutional theory framework, the implementation of quality management standards and excellence models in support of the total quality management (TQM) philosophy and developmental local government within two South African municipalities. The research investigation has been undertaken within the social constructionist paradigm and using the case study method. Interviews and documents were the data sources and thematic analysis was used as a tool to analyse the data by applying a theory-driven coding procedure. The findings from the two research sites, namely Makana Municipality in Grahamstown and Drakenstein Municipality in Paarl reveal that the implementation of quality management standards and excellence models in support of the total quality management (TQM) philosophy in both municipalities was not a smooth process and there were many challenges such as political instability, lack of commitment on the part of the senior leadership and management, staff and skills shortages, resistance by staff to implementation and resource constraints. Institutional theory has proved to be useful in understanding why the Makana and Drakenstein Municipalities implemented quality management standards and excellence models. Because of coercive, mimetic and normative isomorphic pressures affecting the Makana and Drakenstein municipalities, change was imperative if these institutions were to remain relevant and legitimate in order to address its service delivery mandate of effectiveness and efficiency. Institutional theory provided a theoretical lens to understand and appreciate the pressures that affected the municipalities because of its new developmental mandate as encapsulated in new municipal legislation. It also assisted in understanding how institutional entrepreneurs responded to these pressures to conform. The implementation of quality management standards and excellence models in the Makana and Drakenstein municipalities was adversely affected by volatility amongst the political leadership of both municipalities. The successful implementation of these standards and models would require collective action from the political, bureaucratic and procedural entrepreneurs in order to enhance effective, efficient and accountable service delivery. However, in both the Makana and Drakenstein municipalities, institutional entrepreneurs, namely councillors and officials were not working together as a collective to implement quality management standards and excellence models. Evidence has shown that the absence of stable political leadership and noncooperation and collaboration amongst institutional entrepreneurs contributed significantly to the non-institutionalisation of quality management standards and excellence models in these Municipalities. This implies that legitimacy has not been achieved, due to institutional entrepreneurs not collaborating and collectively working with each other to implement the quality management standards and excellence models. Thus, this research study suggests that the strategic and collective role of the political and administrative leadership as institutional entrepreneurs is critical if the municipality is to achieve its aims and objectives, namely effective, efficient, and accountable service delivery in developmental local government. Recommendations in respect of future research and to practitioners have also been offered.
- Full Text:
- Date Issued: 2010
Wattle we do? alien eradication and the 'ecology of fear' on the fringes of a world heritage site, South Africa
- Authors: Merron, James Lawrence
- Date: 2010
- Subjects: Wattles (Plants) -- South Africa -- Eastern Cape Invasive plants -- South Africa -- Eastern Cape South Africa -- Social conditions -- 1994- South Africa -- Politics and government -- 1994- Environmental degradation -- South Africa -- Eastern Cape World Heritage areas -- South Africa -- Eastern Cape Environmentalism -- South Africa -- Eastern Cape -- Social aspects Environmentalism -- South Africa -- Eastern Cape -- Political aspects Social ecology -- South Africa -- Eastern Cape Human ecology -- South Africa -- Eastern Cape Applied anthropology -- South Africa -- Eastern Cape Sustainable development -- South Africa -- Eastern Cape -- Social aspects Nature -- Effect of human beings on -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2092 , http://hdl.handle.net/10962/d1002655
- Description: In their article ―Naturing the Nation: Aliens, the Apocalypse and the Post Colonial State (2001) Jean and John Comaroff look at ―the contemporary predicament of South Africa through the prism of environmental catastrophe. Through it they reveal the context in which alien plants have become an urgent affair of the state. Following their lead, I show how alien plants (particularly Australian wattle) continue to provide grounds for new social and political aspirations in South Africa, though in a different setting. With reference to a group of private landowners on the fringe of a World Heritage Site -- the Baviaanskloof Mega-Reserve, Eastern Cape, South Africa -- I show how an increasingly apocalyptic and xenophobic environmental agenda has influenced local activists seeking to address social and ecological issues in tandem with alien-eradication. These local activists adhere to a particular brand of environmentalism which Milton (1993) argues can be considered a social, cultural and religious phenomenon. The subjects of my main empirical investigation offer practical ways of achieving a transformational end through a new ritual activity in relation to a spread and exchange of environmental ideas and practices on a world-wide scale. On the ground this group practices ecosocietal restoration through which they aspire to mend the bond between people and the land in a spiritual and moral sense, bolstering intrinsic incentives for environmental stewardship and achieving ―cultural reconciliation in an attempt to reimagine what South Africa could be.
- Full Text:
- Date Issued: 2010
- Authors: Merron, James Lawrence
- Date: 2010
- Subjects: Wattles (Plants) -- South Africa -- Eastern Cape Invasive plants -- South Africa -- Eastern Cape South Africa -- Social conditions -- 1994- South Africa -- Politics and government -- 1994- Environmental degradation -- South Africa -- Eastern Cape World Heritage areas -- South Africa -- Eastern Cape Environmentalism -- South Africa -- Eastern Cape -- Social aspects Environmentalism -- South Africa -- Eastern Cape -- Political aspects Social ecology -- South Africa -- Eastern Cape Human ecology -- South Africa -- Eastern Cape Applied anthropology -- South Africa -- Eastern Cape Sustainable development -- South Africa -- Eastern Cape -- Social aspects Nature -- Effect of human beings on -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2092 , http://hdl.handle.net/10962/d1002655
- Description: In their article ―Naturing the Nation: Aliens, the Apocalypse and the Post Colonial State (2001) Jean and John Comaroff look at ―the contemporary predicament of South Africa through the prism of environmental catastrophe. Through it they reveal the context in which alien plants have become an urgent affair of the state. Following their lead, I show how alien plants (particularly Australian wattle) continue to provide grounds for new social and political aspirations in South Africa, though in a different setting. With reference to a group of private landowners on the fringe of a World Heritage Site -- the Baviaanskloof Mega-Reserve, Eastern Cape, South Africa -- I show how an increasingly apocalyptic and xenophobic environmental agenda has influenced local activists seeking to address social and ecological issues in tandem with alien-eradication. These local activists adhere to a particular brand of environmentalism which Milton (1993) argues can be considered a social, cultural and religious phenomenon. The subjects of my main empirical investigation offer practical ways of achieving a transformational end through a new ritual activity in relation to a spread and exchange of environmental ideas and practices on a world-wide scale. On the ground this group practices ecosocietal restoration through which they aspire to mend the bond between people and the land in a spiritual and moral sense, bolstering intrinsic incentives for environmental stewardship and achieving ―cultural reconciliation in an attempt to reimagine what South Africa could be.
- Full Text:
- Date Issued: 2010
Broadening the tax base: a case for the informal real estate sector in Zambia
- Authors: Siame, Chilengwe George
- Date: 2010
- Subjects: Real property and taxation -- Zambia Tax administration and procedure -- Zambia Rental housing -- Taxation -- Law and legislation -- Zambia Informal sector (Economics) -- Taxation -- Law and legislation -- Zambia
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:732 , http://hdl.handle.net/10962/d1003852
- Description: The main objective of the study was to analyze the potential tax collection from the informal rental housing market in Zambia, using household level rental housing data collected for the Lusaka Urban District by the Central Statistical Office (CSO) as a basis for computation and extrapolation to the national level. This data was used to analyze household monthly expenditure on housing (rent), the total number of households in rented accommodation, and the tax regime applicable on rental income, to estimate the potential tax revenue that could be realized from this emerging sector. The estimates indicate that about K9.7 billion revenue could be collected on income from rental housing in Lusaka Urban District alone and a total of K83 billion nationally per annum. This represents about 0.4 percent of the country’s GDP in 2007. Compliance needs to be improved and legislation revised to ensure that the landlords are compelled to remit tax to the Zambia Revenue Authority. The current legislation makes enforcement and compliance difficult as it places the statutory tax burden on tenants, who are very mobile. It is, therefore, recommended that the landlord is made responsible for the payment of taxes due on rental income and that any compliance requirements be enforced against the real estate/property that is generating the income. This study also examines the performance of the presumptive taxation regime in Zambia The study uses data from the Zambia Revenue Authority on revenue collection from presumptive taxes which were introduced to capture income from the informal sectors. The presumptive taxes already introduced in Zambia include: base tax, advance income tax and turnover tax for minibuses and taxi operators. To analyze the performance of the presumptive tax regime, the study utilizes data on imports made by those not registered for taxes, to estimate how much revenue could be generated by imposing a 3 percent turnover tax on the value of their imports at importation. The analysis shows that the Zambia Revenue Authority increased revenue collection from K5.3 billion in 2004 to K33.5 billion in 2007. This improvement in revenue collection is far below the potential, however, which is estimated at over K501 billion on imports of unregistered traders alone. To collect this revenue and expand the tax base, the tax authority needs to improve the administration of advance income tax on unregistered importers, and raise the advance income tax rate to a level where the importer is indifferent between paying the advance tax at the border and paying turnover tax inland.
- Full Text:
- Date Issued: 2010
- Authors: Siame, Chilengwe George
- Date: 2010
- Subjects: Real property and taxation -- Zambia Tax administration and procedure -- Zambia Rental housing -- Taxation -- Law and legislation -- Zambia Informal sector (Economics) -- Taxation -- Law and legislation -- Zambia
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:732 , http://hdl.handle.net/10962/d1003852
- Description: The main objective of the study was to analyze the potential tax collection from the informal rental housing market in Zambia, using household level rental housing data collected for the Lusaka Urban District by the Central Statistical Office (CSO) as a basis for computation and extrapolation to the national level. This data was used to analyze household monthly expenditure on housing (rent), the total number of households in rented accommodation, and the tax regime applicable on rental income, to estimate the potential tax revenue that could be realized from this emerging sector. The estimates indicate that about K9.7 billion revenue could be collected on income from rental housing in Lusaka Urban District alone and a total of K83 billion nationally per annum. This represents about 0.4 percent of the country’s GDP in 2007. Compliance needs to be improved and legislation revised to ensure that the landlords are compelled to remit tax to the Zambia Revenue Authority. The current legislation makes enforcement and compliance difficult as it places the statutory tax burden on tenants, who are very mobile. It is, therefore, recommended that the landlord is made responsible for the payment of taxes due on rental income and that any compliance requirements be enforced against the real estate/property that is generating the income. This study also examines the performance of the presumptive taxation regime in Zambia The study uses data from the Zambia Revenue Authority on revenue collection from presumptive taxes which were introduced to capture income from the informal sectors. The presumptive taxes already introduced in Zambia include: base tax, advance income tax and turnover tax for minibuses and taxi operators. To analyze the performance of the presumptive tax regime, the study utilizes data on imports made by those not registered for taxes, to estimate how much revenue could be generated by imposing a 3 percent turnover tax on the value of their imports at importation. The analysis shows that the Zambia Revenue Authority increased revenue collection from K5.3 billion in 2004 to K33.5 billion in 2007. This improvement in revenue collection is far below the potential, however, which is estimated at over K501 billion on imports of unregistered traders alone. To collect this revenue and expand the tax base, the tax authority needs to improve the administration of advance income tax on unregistered importers, and raise the advance income tax rate to a level where the importer is indifferent between paying the advance tax at the border and paying turnover tax inland.
- Full Text:
- Date Issued: 2010
A proxy approach to protocol interoperability within digital audio networks
- Authors: Igumbor, Osedum Peter
- Date: 2010
- Subjects: Digital communications , Local area networks (Computer networks) , Computer sound processing , Computer networks , Computer network protocols
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4601 , http://hdl.handle.net/10962/d1004852 , Digital communications , Local area networks (Computer networks) , Computer sound processing , Computer networks , Computer network protocols
- Description: Digital audio networks are becoming the preferred solution for the interconnection of professional audio devices. Prominent amongst their advantages are: reduced noise interference, signal multiplexing, and a reduction in the number of cables connecting networked devices. In the context of professional audio, digital networks have been used to connect devices including: mixers, effects units, preamplifiers, breakout boxes, computers, monitoring controllers, and synthesizers. Such networks are governed by protocols that define the connection management rocedures, and device synchronization processes of devices that conform to the protocols. A wide range of digital audio network control protocols exist, each defining specific hardware requirements of devices that conform to them. Device parameter control is achieved by sending a protocol message that indicates the target parameter, and the action that should be performed on the parameter. Typically, a device will conform to only one protocol. By implication, only devices that conform to a specific protocol can communicate with each other, and only a controller that conforms to the protocol can control such devices. This results in the isolation of devices that conform to disparate protocols, since devices of different protocols cannot communicate with each other. This is currently a challenge in the professional music industry, particularly where digital networks are used for audio device control. This investigation seeks to resolve the issue of interoperability between professional audio devices that conform to different digital audio network protocols. This thesis proposes the use of a proxy that allows for the translation of protocol messages, as a solution to the interoperability problem. The proxy abstracts devices of one protocol in terms of another, hence allowing all the networked devices to appear as conforming to the same protocol. The proxy receives messages on behalf of the abstracted device, and then fulfills them in accordance with the protocol that the abstracted device conforms to. Any number of protocol devices can be abstracted within such a proxy. This has the added advantage of allowing a common controller to control devices that conform to the different protocols.
- Full Text:
- Date Issued: 2010
- Authors: Igumbor, Osedum Peter
- Date: 2010
- Subjects: Digital communications , Local area networks (Computer networks) , Computer sound processing , Computer networks , Computer network protocols
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4601 , http://hdl.handle.net/10962/d1004852 , Digital communications , Local area networks (Computer networks) , Computer sound processing , Computer networks , Computer network protocols
- Description: Digital audio networks are becoming the preferred solution for the interconnection of professional audio devices. Prominent amongst their advantages are: reduced noise interference, signal multiplexing, and a reduction in the number of cables connecting networked devices. In the context of professional audio, digital networks have been used to connect devices including: mixers, effects units, preamplifiers, breakout boxes, computers, monitoring controllers, and synthesizers. Such networks are governed by protocols that define the connection management rocedures, and device synchronization processes of devices that conform to the protocols. A wide range of digital audio network control protocols exist, each defining specific hardware requirements of devices that conform to them. Device parameter control is achieved by sending a protocol message that indicates the target parameter, and the action that should be performed on the parameter. Typically, a device will conform to only one protocol. By implication, only devices that conform to a specific protocol can communicate with each other, and only a controller that conforms to the protocol can control such devices. This results in the isolation of devices that conform to disparate protocols, since devices of different protocols cannot communicate with each other. This is currently a challenge in the professional music industry, particularly where digital networks are used for audio device control. This investigation seeks to resolve the issue of interoperability between professional audio devices that conform to different digital audio network protocols. This thesis proposes the use of a proxy that allows for the translation of protocol messages, as a solution to the interoperability problem. The proxy abstracts devices of one protocol in terms of another, hence allowing all the networked devices to appear as conforming to the same protocol. The proxy receives messages on behalf of the abstracted device, and then fulfills them in accordance with the protocol that the abstracted device conforms to. Any number of protocol devices can be abstracted within such a proxy. This has the added advantage of allowing a common controller to control devices that conform to the different protocols.
- Full Text:
- Date Issued: 2010
Israel and Palestine: some critical international relations perspectives on the 'two-state' solution
- Authors: Pienaar, Ashwin Mark
- Date: 2010
- Subjects: Arab-Israeli conflict Jewish-Arab relations Nationalism -- Israel Nationalism -- Palestine Land settlement -- West Bank Land settlement -- Gaza Strip Realism Liberalism Palestinian Arabs -- Politics and government -- 20th century Israel -- Politics and government -- 20th century Israel -- Foreign relations -- Palestine Palestine -- Foreign relations -- Israel
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2820 , http://hdl.handle.net/10962/d1003030
- Description: This research questions whether Israel and Palestine should be divided into two states. Viewed through the International Relations (IR) theories of Realism and Liberalism, the ‘Two-State’ solution is the orthodox policy for Israel and Palestine. But Israelis and Palestinians are interspersed and share many of the same resources making it difficult to create two states. So, this research critiques the aforementioned IR theories which underpin the ‘Two-State’ solution. The conclusion reached is that there ought to be new thinking on how to resolve the Israel-Palestine issue.
- Full Text:
- Date Issued: 2010
Israel and Palestine: some critical international relations perspectives on the 'two-state' solution
- Authors: Pienaar, Ashwin Mark
- Date: 2010
- Subjects: Arab-Israeli conflict Jewish-Arab relations Nationalism -- Israel Nationalism -- Palestine Land settlement -- West Bank Land settlement -- Gaza Strip Realism Liberalism Palestinian Arabs -- Politics and government -- 20th century Israel -- Politics and government -- 20th century Israel -- Foreign relations -- Palestine Palestine -- Foreign relations -- Israel
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2820 , http://hdl.handle.net/10962/d1003030
- Description: This research questions whether Israel and Palestine should be divided into two states. Viewed through the International Relations (IR) theories of Realism and Liberalism, the ‘Two-State’ solution is the orthodox policy for Israel and Palestine. But Israelis and Palestinians are interspersed and share many of the same resources making it difficult to create two states. So, this research critiques the aforementioned IR theories which underpin the ‘Two-State’ solution. The conclusion reached is that there ought to be new thinking on how to resolve the Israel-Palestine issue.
- Full Text:
- Date Issued: 2010
Studies on mixed-species colonies of honeybees, Apis cerana and Apis mellifera
- Authors: Yang, Ming-Xian
- Date: 2010
- Subjects: Bees Apis cerana Honeybee Honeybee -- Behavior Bee culture Honeybee -- Physiology Insect societies Animal communication Bees -- Nests
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5779 , http://hdl.handle.net/10962/d1005467
- Description: The honeybees Apis cerana and Apis mellifera are derived from the same ancestral base about two million years ago. With speciation and evolution, they have acquired many advanced living skills in common, but have also evolved very different living strategies due to different distributions. This thesis is an intensive study of the biology of the mixed-species colonies of these species, the aims of which were to investigate their behavioural relationships and uncover the evolutionary conserved features of their behaviours subsequent to speciation. The results show that the two species can form a stable society to perform normal tasks. First, workers of both species in the mixed-colonies could form the typical retinue behaviour to hetero-species queens, thus indicating that queen pheromones could be spread to and by both species. Secondly, both species did not show significantly different ovarian activation under hetero-species queens, suggesting that the queen pheromones more likely play a role of "honest signal" rather than a "repression" substance in the honeybee colonies. Thirdly, both species could mutually decode each other‘s waggle dances, with unexpectedly low misunderstanding; revealing that the dance language in a dark environment is quite adaptive for cavity-nesting honeybees. Fourthly, workers of both species could cooperate with each other in comb construction, although the combs they built contain many irregular cells. Interestingly, A. cerana workers could be stimulated by A. mellifera workers to perform this task, thus confirming self-organization theory in the colony. Fifthly, A. mellifera workers behaved more "defectively" in thermoregulation, but perhaps because A. cerana workers are more sensitive to changes in hive temperature. Given these differences in strategy, A. mellifera workers‘ performance might in fact reduce conflicts. Lastly, when faced with threats of predatory wasps, both species engaged in aggressive defence. Although they did not learn from each other‘s responses, species-specific strategies were adopted by each of them so that the defence of the mixed-colonies is very effective. I conclude that the two species can adapt to each other‘s efforts and task allocation is reasonably organized allowing mixed-species colonies to reach stability. These results suggest that all of the social behaviours discussed here were highly conserved following speciation. This thesis could provide some clues for the study of honeybee evolution from open-nesting to the transition of cavity-nesting.
- Full Text:
- Date Issued: 2010
- Authors: Yang, Ming-Xian
- Date: 2010
- Subjects: Bees Apis cerana Honeybee Honeybee -- Behavior Bee culture Honeybee -- Physiology Insect societies Animal communication Bees -- Nests
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5779 , http://hdl.handle.net/10962/d1005467
- Description: The honeybees Apis cerana and Apis mellifera are derived from the same ancestral base about two million years ago. With speciation and evolution, they have acquired many advanced living skills in common, but have also evolved very different living strategies due to different distributions. This thesis is an intensive study of the biology of the mixed-species colonies of these species, the aims of which were to investigate their behavioural relationships and uncover the evolutionary conserved features of their behaviours subsequent to speciation. The results show that the two species can form a stable society to perform normal tasks. First, workers of both species in the mixed-colonies could form the typical retinue behaviour to hetero-species queens, thus indicating that queen pheromones could be spread to and by both species. Secondly, both species did not show significantly different ovarian activation under hetero-species queens, suggesting that the queen pheromones more likely play a role of "honest signal" rather than a "repression" substance in the honeybee colonies. Thirdly, both species could mutually decode each other‘s waggle dances, with unexpectedly low misunderstanding; revealing that the dance language in a dark environment is quite adaptive for cavity-nesting honeybees. Fourthly, workers of both species could cooperate with each other in comb construction, although the combs they built contain many irregular cells. Interestingly, A. cerana workers could be stimulated by A. mellifera workers to perform this task, thus confirming self-organization theory in the colony. Fifthly, A. mellifera workers behaved more "defectively" in thermoregulation, but perhaps because A. cerana workers are more sensitive to changes in hive temperature. Given these differences in strategy, A. mellifera workers‘ performance might in fact reduce conflicts. Lastly, when faced with threats of predatory wasps, both species engaged in aggressive defence. Although they did not learn from each other‘s responses, species-specific strategies were adopted by each of them so that the defence of the mixed-colonies is very effective. I conclude that the two species can adapt to each other‘s efforts and task allocation is reasonably organized allowing mixed-species colonies to reach stability. These results suggest that all of the social behaviours discussed here were highly conserved following speciation. This thesis could provide some clues for the study of honeybee evolution from open-nesting to the transition of cavity-nesting.
- Full Text:
- Date Issued: 2010
The advent of the 'Festivore' an exploration of South African audience attendance in the performing arts at the National Arts Festival
- Authors: Antrobus, Richard Roy
- Date: 2010
- Subjects: Standard Bank National Arts Festival -- Economic aspects , Arts -- Economic aspects , Performing arts festivals -- Economic aspects -- South Africa -- Grahamstown , Arts -- South Africa -- Economic aspects , Arts -- South Africa -- Finance , Arts -- South Africa -- Political aspects , Arts audiences -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2130 , http://hdl.handle.net/10962/d1002362
- Description: In South Africa, the performing arts have contributed to enhancing national identity and distinctiveness despite coming up against weak legislation, policy and infrastructure to support their growth and proliferation (Fredericks, 2005: 9). Coupled with a decline in both government and consumer support and the contradictory disparity between valuing the arts and the funding of the arts, theatre companies can no longer rely on the comfort of external subsidies and financial support. In order to be economically viable and sustainable to ensure their survival, there is an increasing demand for theatre companies to look to novel ways of increasing audience demand for theatre and improving audience attendance. However, instead of risking artistic integrity and the performance product to satisfy the market, this research suggests that promotion and development of theatre at arts festivals provides a platform to access a wider theatre-going public, which therefore facilitates a change in the market focus toward appreciation of the product (production). It explores leading arguments pertaining to the attendance of arts and cultural events, namely, Peterson and Simkus (1992), later updated by Peterson‟s (2005)„omnivore-univore‟ argument. The argument purports cultural consumption as binary in nature: either significant and diverse or limited, if not absent altogether. Supported by a number of case-studies, including Chan and Goldthorpe (2005) and Montgomery and Robinson (2008) and Snowball et al. (2009), the investigation challenges Bourdieu‟s (1984) theory on cultural distinction as well as the homology and individualisation argument. In determining the factors that influence cultural taste and consumer behaviour, including motivators and inhibitors of attendance and a predominant emphasis on audience risk and information asymmetry, the research was placed in a local context, providing an overview of the socio-economic theatre environment in South Africa. It investigated the nature, structure and impact of local festivals (as events) in changing audience demand and theatre attendance. With specific reference to the South African National Arts Festival (NAF) the research notes the effects of Hauptfleisch‟s „eventification‟ phenomenon on univore attenders and therefore expands the omnivore-univore theory to include a new breed of attender: the “Festivore”. A case study explored the “Festivore” hypothesis through empirical research, surveys and face-to-face qualitative interviews and on-seat questionnaire responses by festival attenders. Personal interviews and communication was also carried out with leading experts in the field. The data was then analysed using SPSS 13 electronic statistical analysis programme to determine the socio-demographics and the factors that affect theatre attendance of existing, as well as potential target, theatre audiences at the National Arts Festival The study concluded that South African theatre attenders are generally omnivorous consumers and that, more importantly, there seems to be a shift towards „festivorous‟ consumption. Furthermore, evidence supports the development and proliferation of festivals as a means not only to support and promote the arts in South Africa but, more importantly, to generate new theatre audiences and entrench theatre attendance into South African culture.
- Full Text:
- Date Issued: 2010
- Authors: Antrobus, Richard Roy
- Date: 2010
- Subjects: Standard Bank National Arts Festival -- Economic aspects , Arts -- Economic aspects , Performing arts festivals -- Economic aspects -- South Africa -- Grahamstown , Arts -- South Africa -- Economic aspects , Arts -- South Africa -- Finance , Arts -- South Africa -- Political aspects , Arts audiences -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2130 , http://hdl.handle.net/10962/d1002362
- Description: In South Africa, the performing arts have contributed to enhancing national identity and distinctiveness despite coming up against weak legislation, policy and infrastructure to support their growth and proliferation (Fredericks, 2005: 9). Coupled with a decline in both government and consumer support and the contradictory disparity between valuing the arts and the funding of the arts, theatre companies can no longer rely on the comfort of external subsidies and financial support. In order to be economically viable and sustainable to ensure their survival, there is an increasing demand for theatre companies to look to novel ways of increasing audience demand for theatre and improving audience attendance. However, instead of risking artistic integrity and the performance product to satisfy the market, this research suggests that promotion and development of theatre at arts festivals provides a platform to access a wider theatre-going public, which therefore facilitates a change in the market focus toward appreciation of the product (production). It explores leading arguments pertaining to the attendance of arts and cultural events, namely, Peterson and Simkus (1992), later updated by Peterson‟s (2005)„omnivore-univore‟ argument. The argument purports cultural consumption as binary in nature: either significant and diverse or limited, if not absent altogether. Supported by a number of case-studies, including Chan and Goldthorpe (2005) and Montgomery and Robinson (2008) and Snowball et al. (2009), the investigation challenges Bourdieu‟s (1984) theory on cultural distinction as well as the homology and individualisation argument. In determining the factors that influence cultural taste and consumer behaviour, including motivators and inhibitors of attendance and a predominant emphasis on audience risk and information asymmetry, the research was placed in a local context, providing an overview of the socio-economic theatre environment in South Africa. It investigated the nature, structure and impact of local festivals (as events) in changing audience demand and theatre attendance. With specific reference to the South African National Arts Festival (NAF) the research notes the effects of Hauptfleisch‟s „eventification‟ phenomenon on univore attenders and therefore expands the omnivore-univore theory to include a new breed of attender: the “Festivore”. A case study explored the “Festivore” hypothesis through empirical research, surveys and face-to-face qualitative interviews and on-seat questionnaire responses by festival attenders. Personal interviews and communication was also carried out with leading experts in the field. The data was then analysed using SPSS 13 electronic statistical analysis programme to determine the socio-demographics and the factors that affect theatre attendance of existing, as well as potential target, theatre audiences at the National Arts Festival The study concluded that South African theatre attenders are generally omnivorous consumers and that, more importantly, there seems to be a shift towards „festivorous‟ consumption. Furthermore, evidence supports the development and proliferation of festivals as a means not only to support and promote the arts in South Africa but, more importantly, to generate new theatre audiences and entrench theatre attendance into South African culture.
- Full Text:
- Date Issued: 2010
The relationship between organisational culture and financial performance: an exploratory study in a selected financial institution in South Africa
- Authors: Swanepoel, Sybel
- Date: 2010
- Subjects: Corporate culture -- South Africa Financial institutions -- South Africa Banks and banking -- South Africa Economic development -- South Africa Organizational behavior -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:760 , http://hdl.handle.net/10962/d1003881
- Description: This research investigates the relationship between organisational culture and financial performance in a selected financial services institution in South Africa. The banking sector as part of the financial services industry contributes to economic growth in the economy. The banking sector in South Africa is highly concentrated, but also highly competitive. It is important for banks to retain their competitiveness and increased global competition places further pressure on banks to perform financially in order to satisfy the demands of shareholders. The literature reviewed and previous studies both suggest that organisational culture is an important variable that influences organisational performance. For purposes of this research, organisational performance will be measured in terms of financial performance. The concepts of organisational culture and financial performance are discussed and a questionnaire based on Hall’s (1988) theory of organisational competence is used to determine the strength of the levels of the dimensions of competence as indicators of organisational culture within the selected financial institution. The financial performance of the branches within the organisation is determined by calculating certain selected financial performance ratios, namely cost-to-income ratio, cumulative leverage and contribution per employee. A correlation analysis is conducted in order to establish whether there is a statistically significant relationship between organisational culture and financial performance. A conclusion is drawn that there is a statistically significant relationship between the organisational culture and the financial performance of the branches of the selected institution and recommendations are made as to how financial performance can be improved by strengthening the dimensions of competence as indicators of organisational culture. These recommendations include specific actions that can be taken by leaders to improve commitment, collaboration and creativity.
- Full Text:
- Date Issued: 2010
- Authors: Swanepoel, Sybel
- Date: 2010
- Subjects: Corporate culture -- South Africa Financial institutions -- South Africa Banks and banking -- South Africa Economic development -- South Africa Organizational behavior -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:760 , http://hdl.handle.net/10962/d1003881
- Description: This research investigates the relationship between organisational culture and financial performance in a selected financial services institution in South Africa. The banking sector as part of the financial services industry contributes to economic growth in the economy. The banking sector in South Africa is highly concentrated, but also highly competitive. It is important for banks to retain their competitiveness and increased global competition places further pressure on banks to perform financially in order to satisfy the demands of shareholders. The literature reviewed and previous studies both suggest that organisational culture is an important variable that influences organisational performance. For purposes of this research, organisational performance will be measured in terms of financial performance. The concepts of organisational culture and financial performance are discussed and a questionnaire based on Hall’s (1988) theory of organisational competence is used to determine the strength of the levels of the dimensions of competence as indicators of organisational culture within the selected financial institution. The financial performance of the branches within the organisation is determined by calculating certain selected financial performance ratios, namely cost-to-income ratio, cumulative leverage and contribution per employee. A correlation analysis is conducted in order to establish whether there is a statistically significant relationship between organisational culture and financial performance. A conclusion is drawn that there is a statistically significant relationship between the organisational culture and the financial performance of the branches of the selected institution and recommendations are made as to how financial performance can be improved by strengthening the dimensions of competence as indicators of organisational culture. These recommendations include specific actions that can be taken by leaders to improve commitment, collaboration and creativity.
- Full Text:
- Date Issued: 2010
Cost-effective, post-mining environmental restoration of an open-cast phosphate mine at Langebaanweg, South Africa
- Authors: Van Eeden, Joseph Deon
- Date: 2010
- Subjects: Abandoned mined lands reclamation -- South Africa -- Langebaan , Phosphate mines and mining -- Environmental aspects -- South Africa -- Langebaan , Phytoremediation -- South Africa -- Langebaan
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4232 , http://hdl.handle.net/10962/d1003801 , Abandoned mined lands reclamation -- South Africa -- Langebaan , Phosphate mines and mining -- Environmental aspects -- South Africa -- Langebaan , Phytoremediation -- South Africa -- Langebaan
- Description: Approaching the ecological rehabilitation of an open-cast phosphate mine in the West Coast of South Africa during the post-operational phase presented some challenges. The area was extensively modified during the mining operations. Soils from different layers were mixed with topsoil being covered by subsoil, overburden dumps and tailing dams being constructed resulting in extensive cross-zoned soils. Large areas of subsoil areas were exposed on the mine floor with localized and small scale salinity being evident. The modified topography as well as the complex new surface material posed a challenge in terms of identifying suitable local species that could be used to rehabilitate the post-mining environment. The mine area was heavily infested with woody alien invasive plants, such as Acacia cyclops, established in an attempt to reduce the dust and little natural vegetation cover was present. In the arid west coast environment, the four-month-long winter growing season is followed by hot and windy dry summers (Chapter 2) presenting a challenge reestablishing local vegetation in modified soils. Moreover, little was known about the local vegetation in terms of their propagation and use in stabilization techniques as an alternative to exotic vegetation such as the A. cyclops, which had been more often used in revegetation projects. A study was conducted to determine the most efficient and cost-effective methods of vegetative rehabilitation of the Chemfos site (Chapter 1). A review of the literature available at the time as well as approaches that were successfully implemented in other Western Cape rehabilitation projects such as the Du Toitskloof Pass and the Sishen–Saldanha railway line (Chapter 3), were considered. Previous studies on the west coast dunes at Blaauwberg had shown using Marram grass as a dune stabilizer was most successful. Marram grass was tested in trials alongside local grasses, such as Chaetobromus dregeanus and Ehrharta villosa, that showed potential but had not been formally evaluated. The environmental context of Chemfos (Chapter 2) as well as the Conceptual Rehabilitation Plan that considered the modified environment, soils and closure objectives of the mine, were reviewed to determine the most pressing rehabilitationrelated questions that required answers. This led to the final experimental design that was implemented mid-winter in 1996 (Chapter 5). The trials were implemented in the areas perceived to be the most difficult to rehabilitate, namely the mobile sands in the tailings dam and the exposed subsoil or mine floor areas. The use of brushwood together with specific plants and seeds appropriate for the use in either sandy soil or subsoil were evaluated in a variety of combinations and application densities to determine the most effective treatment combination at the minimum effective density. The best initial cover of the tailings dam were recorded in the Ammophila arenaria trials but the use of the local grass species Ehrharta villosa, performed better from year two onwards and was much cheaper to establish. On the subsoil, the trials where a cover of topsoil was used performed better than the combination trials. This indicated that topsoil placement on post-operational phase shaped subsoils during the mining operation to be the most desirable treatment. Initial results of the trials were used as a basis for developing the rehabilitation techniques that were rolled out across the Chemfos landscape. The approaches were refined as indications of trial responses became evident. Lessons learned were incorporated in the adaptive management approach that was followed and the rehabilitation techniques (Chapter 6) were continually re-evaluated and adjusted. This resulted in a significant step towards achieving the overall research objective of finding cost-effective approaches to rehabilitation. Components such as refinement of the seed collection and processing techniques (Chapter 7) where the post-harvest processing cost was significantly reduced by introducing specially designed drying racks. Processing techniques were adjusted to suit the different species, and a variety of mechanical processing options were explored. The scale of the Chemfos project led to the development of new techniques of manufacturing a smoke-derived germination stimulant (Chapter 8) since commercial availability of these products was very limited. The development of FireGrow assisted in the overall aim of reducing cost by increasing germination of seed in the rehabilitation sites using a very cost-effective smoke concentrate. Socio-economical aspects were considered during the implementation as well as the post-closure phases of the rehabilitation and BHPBilliton invested through the agency of the SAMANCOR Trust. This led to the development of livelihoods of the staff that remained in the area and that lived in the mine village. The demography of the population has changed over time in the Green Village as well as the skills that the inhabitants have developed. Thus, the new economic opportunities that were pursued have brought a new lease on life beyond the lifespan of the mine (Chapter 9) once the closure certificate had been issued.
- Full Text:
- Date Issued: 2010
- Authors: Van Eeden, Joseph Deon
- Date: 2010
- Subjects: Abandoned mined lands reclamation -- South Africa -- Langebaan , Phosphate mines and mining -- Environmental aspects -- South Africa -- Langebaan , Phytoremediation -- South Africa -- Langebaan
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4232 , http://hdl.handle.net/10962/d1003801 , Abandoned mined lands reclamation -- South Africa -- Langebaan , Phosphate mines and mining -- Environmental aspects -- South Africa -- Langebaan , Phytoremediation -- South Africa -- Langebaan
- Description: Approaching the ecological rehabilitation of an open-cast phosphate mine in the West Coast of South Africa during the post-operational phase presented some challenges. The area was extensively modified during the mining operations. Soils from different layers were mixed with topsoil being covered by subsoil, overburden dumps and tailing dams being constructed resulting in extensive cross-zoned soils. Large areas of subsoil areas were exposed on the mine floor with localized and small scale salinity being evident. The modified topography as well as the complex new surface material posed a challenge in terms of identifying suitable local species that could be used to rehabilitate the post-mining environment. The mine area was heavily infested with woody alien invasive plants, such as Acacia cyclops, established in an attempt to reduce the dust and little natural vegetation cover was present. In the arid west coast environment, the four-month-long winter growing season is followed by hot and windy dry summers (Chapter 2) presenting a challenge reestablishing local vegetation in modified soils. Moreover, little was known about the local vegetation in terms of their propagation and use in stabilization techniques as an alternative to exotic vegetation such as the A. cyclops, which had been more often used in revegetation projects. A study was conducted to determine the most efficient and cost-effective methods of vegetative rehabilitation of the Chemfos site (Chapter 1). A review of the literature available at the time as well as approaches that were successfully implemented in other Western Cape rehabilitation projects such as the Du Toitskloof Pass and the Sishen–Saldanha railway line (Chapter 3), were considered. Previous studies on the west coast dunes at Blaauwberg had shown using Marram grass as a dune stabilizer was most successful. Marram grass was tested in trials alongside local grasses, such as Chaetobromus dregeanus and Ehrharta villosa, that showed potential but had not been formally evaluated. The environmental context of Chemfos (Chapter 2) as well as the Conceptual Rehabilitation Plan that considered the modified environment, soils and closure objectives of the mine, were reviewed to determine the most pressing rehabilitationrelated questions that required answers. This led to the final experimental design that was implemented mid-winter in 1996 (Chapter 5). The trials were implemented in the areas perceived to be the most difficult to rehabilitate, namely the mobile sands in the tailings dam and the exposed subsoil or mine floor areas. The use of brushwood together with specific plants and seeds appropriate for the use in either sandy soil or subsoil were evaluated in a variety of combinations and application densities to determine the most effective treatment combination at the minimum effective density. The best initial cover of the tailings dam were recorded in the Ammophila arenaria trials but the use of the local grass species Ehrharta villosa, performed better from year two onwards and was much cheaper to establish. On the subsoil, the trials where a cover of topsoil was used performed better than the combination trials. This indicated that topsoil placement on post-operational phase shaped subsoils during the mining operation to be the most desirable treatment. Initial results of the trials were used as a basis for developing the rehabilitation techniques that were rolled out across the Chemfos landscape. The approaches were refined as indications of trial responses became evident. Lessons learned were incorporated in the adaptive management approach that was followed and the rehabilitation techniques (Chapter 6) were continually re-evaluated and adjusted. This resulted in a significant step towards achieving the overall research objective of finding cost-effective approaches to rehabilitation. Components such as refinement of the seed collection and processing techniques (Chapter 7) where the post-harvest processing cost was significantly reduced by introducing specially designed drying racks. Processing techniques were adjusted to suit the different species, and a variety of mechanical processing options were explored. The scale of the Chemfos project led to the development of new techniques of manufacturing a smoke-derived germination stimulant (Chapter 8) since commercial availability of these products was very limited. The development of FireGrow assisted in the overall aim of reducing cost by increasing germination of seed in the rehabilitation sites using a very cost-effective smoke concentrate. Socio-economical aspects were considered during the implementation as well as the post-closure phases of the rehabilitation and BHPBilliton invested through the agency of the SAMANCOR Trust. This led to the development of livelihoods of the staff that remained in the area and that lived in the mine village. The demography of the population has changed over time in the Green Village as well as the skills that the inhabitants have developed. Thus, the new economic opportunities that were pursued have brought a new lease on life beyond the lifespan of the mine (Chapter 9) once the closure certificate had been issued.
- Full Text:
- Date Issued: 2010
The role of teachers' resource centres from the perspective of school managers and teachers
- Authors: Mbambo, Markus S
- Date: 2010
- Subjects: Education -- Namibia Teaching -- Aids and devices -- Namibia Resource programs (Education) -- Namibia Teachers -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1754 , http://hdl.handle.net/10962/d1003638
- Description: This study aimed to investigate the role played by the Teachers’ Resource Centre (TRC) in Namibia in helping schools to provide quality education. The TRC concept began in Britain in the 1960s, where it was introduced as a means of supporting the professional development of teachers and giving them access to a range of educational resources. From the 1970s, the concept was promoted further afield as an effective strategy for dealing with teachers’ needs. TRCs emerged in Namibia in the 1980s under the auspices of the then Department of Education of the South African government. By 1989, only four TRCs were in existence, namely, Katutura, Tsumeb, Otjiwarongo and Rundu, plus one in the whites-only training college in Windhoek. In September 1991, the Ministry of Education and Culture (MEC) in Namibia produced a five-year plan that led to the diversification of the TRC network in Namibia. Yet, despite the now widespread existence of TRCs, little is known of whether and to what extent their services are helping teachers to provide quality education. This constitutes a gap in the literature that this study hopes in part to fill. The study was conducted using a case study approach in three schools in the Kavango region of Namibia. It made use of questionnaires, interviews, focus group discussions and data analysis to gather and interpret data. The study’s finding is that TRCs are indeed beneficial to schools in their vicinity, despite their current limited capacities. However, TRCs should be better able to redress the poor quality of education in many schools due to a lack of resources, de-motivated teachers and other factors. This study therefore recommends that enough funds be made available for the TRCs to acquire the resources they need adequately to support quality educational processes. Furthermore, the study found that it is imperative for individuals in TRCs and schools to learn how to facilitate relevant transformation in their organisations’ efficiency and effectiveness. Thus the study recommends a transformational leadership approach as most appropriate for managing learning and bringing about successful change in these organisations. The significance of this research is that it sheds some light on the effectiveness of TRCs as a strategy for supporting teachers in the delivery of quality teaching. It also suggests potential areas in which stakeholders might usefully cooperate in their endeavours to realise quality education.
- Full Text:
- Date Issued: 2010
- Authors: Mbambo, Markus S
- Date: 2010
- Subjects: Education -- Namibia Teaching -- Aids and devices -- Namibia Resource programs (Education) -- Namibia Teachers -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1754 , http://hdl.handle.net/10962/d1003638
- Description: This study aimed to investigate the role played by the Teachers’ Resource Centre (TRC) in Namibia in helping schools to provide quality education. The TRC concept began in Britain in the 1960s, where it was introduced as a means of supporting the professional development of teachers and giving them access to a range of educational resources. From the 1970s, the concept was promoted further afield as an effective strategy for dealing with teachers’ needs. TRCs emerged in Namibia in the 1980s under the auspices of the then Department of Education of the South African government. By 1989, only four TRCs were in existence, namely, Katutura, Tsumeb, Otjiwarongo and Rundu, plus one in the whites-only training college in Windhoek. In September 1991, the Ministry of Education and Culture (MEC) in Namibia produced a five-year plan that led to the diversification of the TRC network in Namibia. Yet, despite the now widespread existence of TRCs, little is known of whether and to what extent their services are helping teachers to provide quality education. This constitutes a gap in the literature that this study hopes in part to fill. The study was conducted using a case study approach in three schools in the Kavango region of Namibia. It made use of questionnaires, interviews, focus group discussions and data analysis to gather and interpret data. The study’s finding is that TRCs are indeed beneficial to schools in their vicinity, despite their current limited capacities. However, TRCs should be better able to redress the poor quality of education in many schools due to a lack of resources, de-motivated teachers and other factors. This study therefore recommends that enough funds be made available for the TRCs to acquire the resources they need adequately to support quality educational processes. Furthermore, the study found that it is imperative for individuals in TRCs and schools to learn how to facilitate relevant transformation in their organisations’ efficiency and effectiveness. Thus the study recommends a transformational leadership approach as most appropriate for managing learning and bringing about successful change in these organisations. The significance of this research is that it sheds some light on the effectiveness of TRCs as a strategy for supporting teachers in the delivery of quality teaching. It also suggests potential areas in which stakeholders might usefully cooperate in their endeavours to realise quality education.
- Full Text:
- Date Issued: 2010
The effects of booster breaks during a sedentary night shift on physiological, psychomotor, psycho-physiological, and cognitive performance over a 3 night shift habituation phase
- Authors: Lombard, Wesley Ross
- Date: 2010
- Subjects: Night work , Shift systems , Performance , Exercise , Exercise -- Physiological aspects , Exercise -- Psychological aspects , Cognition -- Effect of exercise on , Motor ability
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5116 , http://hdl.handle.net/10962/d1005194 , Night work , Shift systems , Performance , Exercise , Exercise -- Physiological aspects , Exercise -- Psychological aspects , Cognition -- Effect of exercise on , Motor ability
- Description: Despite extensive research into shift work, workers working under rotating shift conditions are still plagued by the effects of the desynchronisation resulting from working against their natural circadian rhythms. Additionally, modern industries are shifting towards tasks requiring greater cognitive demand with less manual labour incorporated into the tasks. Research into operator based tasks, and hence those of a sedentary cognitive base both during day and night shifts, has been focusing on the effectiveness of the standard rest/break schedule. Research indicating that the standard rest break schedule is often ineffective in eliminating operator discomfort and performance deterioration, with these affects argued to be more pronounced during a night shift schedule. Therefore current research set out to investigate alternative rest break schedules, incorporating a short bout of physical activity and stretching exercises which are proposed to enhance performance and subjective mood, while eliminating operator discomfort for sedentary based cognitive tasks. Three conditions were tested during a three day habituation shift cycle within a laboratory, incorporating two night shift groups (control and experimental) and a control day shift group. Twelve subjects made up each group, with the two night shift groups completing the shift schedule together. The control groups followed a typical 8 hour shift schedule while the experimental group performed a booster break (exercise and stretches) activity for 7.5 minutes every hour during the night shift schedule. Over the course of the shift, subjects completed a battery of six tests providing data on physiological measurements (heart rate and temperature), performance criteria (reaction time responses, memory and neurobiological) and subjective measures. Responses obtained for all the different parameters measured indicated a strong circadian influence for the majority of the variables, indicating the course of natural down regulation within physiological and performance criteria over the night shift. The booster break significantly improved reaction time performance, subjective ratings and resulted in a high sustainable activity level. Day shift comparisons indicating that within subjective measures and reaction time performance, the booster break resulted in similar responses to those of the day shift workers, while the control night shift groups reported significantly lowers results. Additionally, the booster break had positive influences during the circadian nadir, significantly improving parameters of performance and subjective ratings of sleepiness. The results of this study indicating which variables are strong predictors and indicators of the oscillations in performance and subjective ratings due to the circadian changes. The booster break interventions had positive effects on subjective ratings and reaction time performance, while also being argued to decrease the burden placed on the cardiac system as a result of increased sympathetic tone during the night shift, while additionally resulting in similar responses to those of day shift workers. Further studies are required, however, to provide conclusive evidence particularly within a working situation over a longer shift schedule.
- Full Text:
- Date Issued: 2010
- Authors: Lombard, Wesley Ross
- Date: 2010
- Subjects: Night work , Shift systems , Performance , Exercise , Exercise -- Physiological aspects , Exercise -- Psychological aspects , Cognition -- Effect of exercise on , Motor ability
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5116 , http://hdl.handle.net/10962/d1005194 , Night work , Shift systems , Performance , Exercise , Exercise -- Physiological aspects , Exercise -- Psychological aspects , Cognition -- Effect of exercise on , Motor ability
- Description: Despite extensive research into shift work, workers working under rotating shift conditions are still plagued by the effects of the desynchronisation resulting from working against their natural circadian rhythms. Additionally, modern industries are shifting towards tasks requiring greater cognitive demand with less manual labour incorporated into the tasks. Research into operator based tasks, and hence those of a sedentary cognitive base both during day and night shifts, has been focusing on the effectiveness of the standard rest/break schedule. Research indicating that the standard rest break schedule is often ineffective in eliminating operator discomfort and performance deterioration, with these affects argued to be more pronounced during a night shift schedule. Therefore current research set out to investigate alternative rest break schedules, incorporating a short bout of physical activity and stretching exercises which are proposed to enhance performance and subjective mood, while eliminating operator discomfort for sedentary based cognitive tasks. Three conditions were tested during a three day habituation shift cycle within a laboratory, incorporating two night shift groups (control and experimental) and a control day shift group. Twelve subjects made up each group, with the two night shift groups completing the shift schedule together. The control groups followed a typical 8 hour shift schedule while the experimental group performed a booster break (exercise and stretches) activity for 7.5 minutes every hour during the night shift schedule. Over the course of the shift, subjects completed a battery of six tests providing data on physiological measurements (heart rate and temperature), performance criteria (reaction time responses, memory and neurobiological) and subjective measures. Responses obtained for all the different parameters measured indicated a strong circadian influence for the majority of the variables, indicating the course of natural down regulation within physiological and performance criteria over the night shift. The booster break significantly improved reaction time performance, subjective ratings and resulted in a high sustainable activity level. Day shift comparisons indicating that within subjective measures and reaction time performance, the booster break resulted in similar responses to those of the day shift workers, while the control night shift groups reported significantly lowers results. Additionally, the booster break had positive influences during the circadian nadir, significantly improving parameters of performance and subjective ratings of sleepiness. The results of this study indicating which variables are strong predictors and indicators of the oscillations in performance and subjective ratings due to the circadian changes. The booster break interventions had positive effects on subjective ratings and reaction time performance, while also being argued to decrease the burden placed on the cardiac system as a result of increased sympathetic tone during the night shift, while additionally resulting in similar responses to those of day shift workers. Further studies are required, however, to provide conclusive evidence particularly within a working situation over a longer shift schedule.
- Full Text:
- Date Issued: 2010
Validation of high frequency propagation prediction models over Africa
- Authors: Tshisaphungo, Mpho
- Date: 2010
- Subjects: Ionospheric radio wave propagation , Ionospheric radio wave propagation -- Forecasting , Radio meteorology , Radio wave propagation -- Africa , Ionosphere -- Africa -- Radio waves , Atmospheric physics -- Africa , Shortwave radio -- Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5553 , http://hdl.handle.net/10962/d1015239
- Description: The ionosphere is an important factor in high frequency (HF) radio propagation providing an opportunity to study ionospheric variability as well as the space weather conditions under which HF communication can take place. This thesis presents the validation of HF propagation conditions for the Ionospheric Communication Enhanced Profile Analysis and Circuit (ICEPAC) and Advanced Stand Alone Prediction System (ASAPS) models over Africa by comparing predictions with the measured data obtained from the International Beacon Project (IBP). Since these models were not developed using information on the African region, a more accurate HF propagation prediction tool is required. Two IBP transmitter stations are considered, Ruaraka, Kenya (1.24°S, 36.88°E) and Pretoria, South Africa (25.45°S, 28.10°E) with one beacon receiver station located in Hermanus, South Africa (34.27°S, 19.l2°E). The potential of these models in terms of HF propagation conditions is illustrated. An attempt to draw conclusions for future improvement of the models is also presented. Results show a low prediction accuracy for both ICEPAC and ASAPS models, although ICEPAC provided more accurate predictions for daily HF propagation conditions. This thesis suggests that the development of a new HF propagation prediction tool for the African region or the modification of one of the existing models to accommodate the African region, taking into account the importance of the African ionospheric region, should be considered as an option to ensure more accurate HF Propagation predictions over this region.
- Full Text:
- Date Issued: 2010
- Authors: Tshisaphungo, Mpho
- Date: 2010
- Subjects: Ionospheric radio wave propagation , Ionospheric radio wave propagation -- Forecasting , Radio meteorology , Radio wave propagation -- Africa , Ionosphere -- Africa -- Radio waves , Atmospheric physics -- Africa , Shortwave radio -- Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5553 , http://hdl.handle.net/10962/d1015239
- Description: The ionosphere is an important factor in high frequency (HF) radio propagation providing an opportunity to study ionospheric variability as well as the space weather conditions under which HF communication can take place. This thesis presents the validation of HF propagation conditions for the Ionospheric Communication Enhanced Profile Analysis and Circuit (ICEPAC) and Advanced Stand Alone Prediction System (ASAPS) models over Africa by comparing predictions with the measured data obtained from the International Beacon Project (IBP). Since these models were not developed using information on the African region, a more accurate HF propagation prediction tool is required. Two IBP transmitter stations are considered, Ruaraka, Kenya (1.24°S, 36.88°E) and Pretoria, South Africa (25.45°S, 28.10°E) with one beacon receiver station located in Hermanus, South Africa (34.27°S, 19.l2°E). The potential of these models in terms of HF propagation conditions is illustrated. An attempt to draw conclusions for future improvement of the models is also presented. Results show a low prediction accuracy for both ICEPAC and ASAPS models, although ICEPAC provided more accurate predictions for daily HF propagation conditions. This thesis suggests that the development of a new HF propagation prediction tool for the African region or the modification of one of the existing models to accommodate the African region, taking into account the importance of the African ionospheric region, should be considered as an option to ensure more accurate HF Propagation predictions over this region.
- Full Text:
- Date Issued: 2010
Rhodes University Research Report 2010
- Rhodes University, Roberts, Jaine
- Authors: Rhodes University , Roberts, Jaine
- Date: 2010
- Language: English
- Type: Text
- Identifier: vital:565 , http://hdl.handle.net/10962/d1011968
- Description: From Introduction: In 2010, the total subsidy earning accredited research output count for Rhodes University of 615.3 units represents an increase of 9% on the previous year. By far the major contributor to this growth was the significant increase in both PhD (37.5% up on 2009) and Masters by thesis students (34.5% up on 2009). Rhodes contributed 3.3% of all accredited research output in the public higher education sector in 2010 (0.1% up on 2009). With 1.9% of academic staff in the system, Rhodes retained its place amongst the top three most productive universities as measured by accredited publications per academic. Rhodes exceeds the DHET research output norm for universities by 53%. In 2010, the total accredited publication output count for Rhodes University of 325.33 units represented a decline over 2009 of 7.3 percent. This followed two years of steep growth during which accredited research publication output grew by 28%. Accredited publication output for 2010 consisted mainly of journals at 89.9%, with conference proceedings at 7.2% and books and book chapters at 2.9% making far smaller contributions. This mix is roughly in line with the sector as a whole. It has been recognised that books and book chapters are underappreciated in relation to journals, and recommendations to increase the weighted points that they attract as proposed by ASSAf1 are awaiting approval by the DHET. and book chapters submitted, because the hurdle of independent reviewing is not always met by the publishing avenues chosen by authors. The University has become increasingly reliant on research funding in recent years as a larger proportion of its budget, and attention at university council level is being given to ensuring that appropriate systems and support structures for researchers are in place. I add my warm thanks and congratulations to all of our researchers, funders, collaborators and partners who contributed to the excellent research results of 2010. , A Publication of the Rhodes Research Office,compiled and edited by Jaine Roberts
- Full Text:
- Date Issued: 2010
- Authors: Rhodes University , Roberts, Jaine
- Date: 2010
- Language: English
- Type: Text
- Identifier: vital:565 , http://hdl.handle.net/10962/d1011968
- Description: From Introduction: In 2010, the total subsidy earning accredited research output count for Rhodes University of 615.3 units represents an increase of 9% on the previous year. By far the major contributor to this growth was the significant increase in both PhD (37.5% up on 2009) and Masters by thesis students (34.5% up on 2009). Rhodes contributed 3.3% of all accredited research output in the public higher education sector in 2010 (0.1% up on 2009). With 1.9% of academic staff in the system, Rhodes retained its place amongst the top three most productive universities as measured by accredited publications per academic. Rhodes exceeds the DHET research output norm for universities by 53%. In 2010, the total accredited publication output count for Rhodes University of 325.33 units represented a decline over 2009 of 7.3 percent. This followed two years of steep growth during which accredited research publication output grew by 28%. Accredited publication output for 2010 consisted mainly of journals at 89.9%, with conference proceedings at 7.2% and books and book chapters at 2.9% making far smaller contributions. This mix is roughly in line with the sector as a whole. It has been recognised that books and book chapters are underappreciated in relation to journals, and recommendations to increase the weighted points that they attract as proposed by ASSAf1 are awaiting approval by the DHET. and book chapters submitted, because the hurdle of independent reviewing is not always met by the publishing avenues chosen by authors. The University has become increasingly reliant on research funding in recent years as a larger proportion of its budget, and attention at university council level is being given to ensuring that appropriate systems and support structures for researchers are in place. I add my warm thanks and congratulations to all of our researchers, funders, collaborators and partners who contributed to the excellent research results of 2010. , A Publication of the Rhodes Research Office,compiled and edited by Jaine Roberts
- Full Text:
- Date Issued: 2010
Multilingualism and ICT education at Rhodes University: an exploratory study
- Authors: Dalvit, Lorenzo
- Date: 2010
- Subjects: Educational technology -- South Africa Educational equalization -- South Africa Digital divide -- South Africa Information technology -- Social aspects -- South Africa Educational innovations Information technology -- Study and teaching Language and education -- South Africa Native language and education -- South Africa Rhodes University -- Students -- Attitudes Computer science -- Study and teaching (Higher)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1673 , http://hdl.handle.net/10962/d1003556
- Description: In South Africa, the linguistic hegemony of English over the African languages in the academic field reproduces unequal power relationships between their speakers. The present study shows that an intervention shaped by a counterhegemonic ideology can change the attitudes of Black university students, key players in spearheading social change. Usign statistical analysis and survey methodologies, this research explored the hegemonic role of English as the only language of learning and teaching (LoLT) in the discipline of Computer Science (CS) at Rhodes University. The study found that those speakers of an African language who are the most disadvantaged by the use of English as LoLT are also the most likely to resist a more extensive use of their mother tongue as an alternative. A group of such students were involved in the development and use of an online glossary of CS terms translated, explained and exemplified in an African language (isiXhosa). This experience increased the support for the use of African languages as additional LoLT, even in the Englishdominated field of study of Computer Science. This is an initial step towards promoting linguistic equality between English and African languages and social equality between their speakers.
- Full Text:
- Date Issued: 2010
- Authors: Dalvit, Lorenzo
- Date: 2010
- Subjects: Educational technology -- South Africa Educational equalization -- South Africa Digital divide -- South Africa Information technology -- Social aspects -- South Africa Educational innovations Information technology -- Study and teaching Language and education -- South Africa Native language and education -- South Africa Rhodes University -- Students -- Attitudes Computer science -- Study and teaching (Higher)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1673 , http://hdl.handle.net/10962/d1003556
- Description: In South Africa, the linguistic hegemony of English over the African languages in the academic field reproduces unequal power relationships between their speakers. The present study shows that an intervention shaped by a counterhegemonic ideology can change the attitudes of Black university students, key players in spearheading social change. Usign statistical analysis and survey methodologies, this research explored the hegemonic role of English as the only language of learning and teaching (LoLT) in the discipline of Computer Science (CS) at Rhodes University. The study found that those speakers of an African language who are the most disadvantaged by the use of English as LoLT are also the most likely to resist a more extensive use of their mother tongue as an alternative. A group of such students were involved in the development and use of an online glossary of CS terms translated, explained and exemplified in an African language (isiXhosa). This experience increased the support for the use of African languages as additional LoLT, even in the Englishdominated field of study of Computer Science. This is an initial step towards promoting linguistic equality between English and African languages and social equality between their speakers.
- Full Text:
- Date Issued: 2010
Development and assessment of minocycline sustained release capsule formulations
- Sachikonye, Tinotenda Chipo Victoria
- Authors: Sachikonye, Tinotenda Chipo Victoria
- Date: 2010
- Subjects: Drugs -- Controlled release , Drugs -- Dosage forms , Capsules (Pharmacy) , Drugs -- Administration , Acne -- Treatment , Tetracyclines , Antibiotics -- Side effects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3854 , http://hdl.handle.net/10962/d1013127
- Description: The use of minocycline for the treatment of a broad range of systemic infections and for severe acne has been associated with vestibular side effects. The severity of side effects may lead to poor adherence to therapy by patients. The use of sustained release formulations of minocycline that display slow dissolution of minocycline following administration may be beneficial in reducing the incidence and severity of side effects. Therefore, sustained release capsule dosage forms containing 100 mg minocycline (base) were manufactured and assessed for use as sustained release oral dosage forms of minocycline. Minocycline sustained release capsules were manufactured based on matrix technologies using hydroxypropylmethyl cellulose (HPMC) and Compritol® as release retarding polymers. The rate and extent of minocycline release from the capsules was evaluated using USP Apparatus 1 and samples were analysed using a validated High Performance Liquid Chromatographic (HPLC) method with ultraviolet (UV) detection. Differences in the rate and extent of minocycline release from formulations manufactured using HPMC or Compritol® were influenced by the concentration of polymer used in the formulations. The rate and extent of minocycline release was faster and greater when low concentrations of polymer were used in formulations. The effect of different excipients on the release pattern(s) of minocycline and particularly their potential to optimise minocycline release from experimental formulations was investigated. The use of diluents such as lactose and microcrystalline cellulose (MCC) revealed that lactose facilitated minocycline release when HPMC was used as the polymer matrix. In contrast, the use of lactose as diluent resulted in slower release of minocycline from Compritol® based formulations. The addition of sodium starch glycolate to HPMC based formulations resulted in slower release of minocycline than when no sodium starch glycolate was used. Compritol® based formulations were observed to release minocycline faster following addition of sodium starch glycolate and Poloxamer 188 to experimental formulations. In vitro dissolution profiles were compared to a target or reference profile using the difference and similarity factors, ƒ1 and ƒ2 , and a one way analysis of variance (ANOVA). In addition, the mechanism of minocycline release was elucidated following fitting of dissolution data to the Korsmeyer-Peppas, Higuchi and Zero order models. Minocycline release kinetics were best described by the Korsmeyer-Peppas model and the values of the release exponent, n (italics), revealed that drug release was a result of the combined effects of minocycline diffusion through matrices and erosion of the matrices. These in vitro dissolution profiles were better fit to the Higuchi model than to the Zero order model. Two formulations that displayed a fit to the Zero order model were identified for further studies as potential dosage forms for sustained release minocycline.
- Full Text:
- Date Issued: 2010
- Authors: Sachikonye, Tinotenda Chipo Victoria
- Date: 2010
- Subjects: Drugs -- Controlled release , Drugs -- Dosage forms , Capsules (Pharmacy) , Drugs -- Administration , Acne -- Treatment , Tetracyclines , Antibiotics -- Side effects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3854 , http://hdl.handle.net/10962/d1013127
- Description: The use of minocycline for the treatment of a broad range of systemic infections and for severe acne has been associated with vestibular side effects. The severity of side effects may lead to poor adherence to therapy by patients. The use of sustained release formulations of minocycline that display slow dissolution of minocycline following administration may be beneficial in reducing the incidence and severity of side effects. Therefore, sustained release capsule dosage forms containing 100 mg minocycline (base) were manufactured and assessed for use as sustained release oral dosage forms of minocycline. Minocycline sustained release capsules were manufactured based on matrix technologies using hydroxypropylmethyl cellulose (HPMC) and Compritol® as release retarding polymers. The rate and extent of minocycline release from the capsules was evaluated using USP Apparatus 1 and samples were analysed using a validated High Performance Liquid Chromatographic (HPLC) method with ultraviolet (UV) detection. Differences in the rate and extent of minocycline release from formulations manufactured using HPMC or Compritol® were influenced by the concentration of polymer used in the formulations. The rate and extent of minocycline release was faster and greater when low concentrations of polymer were used in formulations. The effect of different excipients on the release pattern(s) of minocycline and particularly their potential to optimise minocycline release from experimental formulations was investigated. The use of diluents such as lactose and microcrystalline cellulose (MCC) revealed that lactose facilitated minocycline release when HPMC was used as the polymer matrix. In contrast, the use of lactose as diluent resulted in slower release of minocycline from Compritol® based formulations. The addition of sodium starch glycolate to HPMC based formulations resulted in slower release of minocycline than when no sodium starch glycolate was used. Compritol® based formulations were observed to release minocycline faster following addition of sodium starch glycolate and Poloxamer 188 to experimental formulations. In vitro dissolution profiles were compared to a target or reference profile using the difference and similarity factors, ƒ1 and ƒ2 , and a one way analysis of variance (ANOVA). In addition, the mechanism of minocycline release was elucidated following fitting of dissolution data to the Korsmeyer-Peppas, Higuchi and Zero order models. Minocycline release kinetics were best described by the Korsmeyer-Peppas model and the values of the release exponent, n (italics), revealed that drug release was a result of the combined effects of minocycline diffusion through matrices and erosion of the matrices. These in vitro dissolution profiles were better fit to the Higuchi model than to the Zero order model. Two formulations that displayed a fit to the Zero order model were identified for further studies as potential dosage forms for sustained release minocycline.
- Full Text:
- Date Issued: 2010
Economic consequences of ecological change: restoration options for the Mfolozi floodplain and implications for Lake St. Lucia, South Africa
- Authors: Collings, Sandy Lyn
- Date: 2010
- Subjects: Lake ecology -- South Africa -- Saint Lucia, Lake , Ecology -- Economic aspects -- South Africa -- Kwazulu-Natal , Wetland ecology -- South Africa -- Kwazulu-Natal , Ecosystem services -- South Africa -- Kwazulu-Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4744 , http://hdl.handle.net/10962/d1006950 , Lake ecology -- South Africa -- Saint Lucia, Lake , Ecology -- Economic aspects -- South Africa -- Kwazulu-Natal , Wetland ecology -- South Africa -- Kwazulu-Natal , Ecosystem services -- South Africa -- Kwazulu-Natal
- Description: Lake St Lucia in northern KwaZulu-Natal, South Africa, experiences severe ecological stress during dry periods largely as a result of diminishing freshwater supplies and conditions of hypersalinity. Possible intervention involves diverting the Mfolozi River to the St Lucia Lake system. However, due to high sediment loading, water from the Mfolozi river requires considerable filtration before a link can be established. A suggested option considered in this study is to restore the existing sugarcane farmlands on the Mfolozi Floodplain (~20 800 ha) to previous wetland conditions to reinstate a sediment removal function amongst other benefits. Proposed restoration will have a direct impact on the industries currently supported by the iSimangaliso Wetland Park and the Mfolozi Floodplain (tourism, sugar, conservation). to understand a measure of such impacts, ecosystem services for both Lake St Lucia and the Mfolozi Floodplain were analysed (flood alleviation, water provision, water purification, sediment regulation, tourism, fisheries, vegetation for harvest, existence, cultural and research). Annual economic values for each ecosystem service were determined by means of valuation methods that included benefit transfer and replacement cost. Results showed a current annual minimum value of the Mfolozi Floodplain and Lake St Lucia as greater than R21 million and R1.1 billion respectively. Partial restoration of the floodplain (~6 000 ha) is expected to increase the sum of all ecosystem services values by approximately 26% for the Mfolozi Floodplain and by 23% for the St Lucia System. Full restoration (~20 800 ha) increases the total ecosystem services value by 88% and 50% for the Mfolozi Floodplain and St Lucia System respectively. Results showed that economic values for existence, fisheries, tourism and water provision increase by the greatest percentage for the St Lucia System under both restoration scenarios. Partial and full restoration of the floodplain will result in the greatest increases in economic value for the services existence, tourism, fisheries and the harvesting of vegetation on the Mfolozi Floodplain.
- Full Text:
- Date Issued: 2010
- Authors: Collings, Sandy Lyn
- Date: 2010
- Subjects: Lake ecology -- South Africa -- Saint Lucia, Lake , Ecology -- Economic aspects -- South Africa -- Kwazulu-Natal , Wetland ecology -- South Africa -- Kwazulu-Natal , Ecosystem services -- South Africa -- Kwazulu-Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4744 , http://hdl.handle.net/10962/d1006950 , Lake ecology -- South Africa -- Saint Lucia, Lake , Ecology -- Economic aspects -- South Africa -- Kwazulu-Natal , Wetland ecology -- South Africa -- Kwazulu-Natal , Ecosystem services -- South Africa -- Kwazulu-Natal
- Description: Lake St Lucia in northern KwaZulu-Natal, South Africa, experiences severe ecological stress during dry periods largely as a result of diminishing freshwater supplies and conditions of hypersalinity. Possible intervention involves diverting the Mfolozi River to the St Lucia Lake system. However, due to high sediment loading, water from the Mfolozi river requires considerable filtration before a link can be established. A suggested option considered in this study is to restore the existing sugarcane farmlands on the Mfolozi Floodplain (~20 800 ha) to previous wetland conditions to reinstate a sediment removal function amongst other benefits. Proposed restoration will have a direct impact on the industries currently supported by the iSimangaliso Wetland Park and the Mfolozi Floodplain (tourism, sugar, conservation). to understand a measure of such impacts, ecosystem services for both Lake St Lucia and the Mfolozi Floodplain were analysed (flood alleviation, water provision, water purification, sediment regulation, tourism, fisheries, vegetation for harvest, existence, cultural and research). Annual economic values for each ecosystem service were determined by means of valuation methods that included benefit transfer and replacement cost. Results showed a current annual minimum value of the Mfolozi Floodplain and Lake St Lucia as greater than R21 million and R1.1 billion respectively. Partial restoration of the floodplain (~6 000 ha) is expected to increase the sum of all ecosystem services values by approximately 26% for the Mfolozi Floodplain and by 23% for the St Lucia System. Full restoration (~20 800 ha) increases the total ecosystem services value by 88% and 50% for the Mfolozi Floodplain and St Lucia System respectively. Results showed that economic values for existence, fisheries, tourism and water provision increase by the greatest percentage for the St Lucia System under both restoration scenarios. Partial and full restoration of the floodplain will result in the greatest increases in economic value for the services existence, tourism, fisheries and the harvesting of vegetation on the Mfolozi Floodplain.
- Full Text:
- Date Issued: 2010
Improving explanation writing skills of junior secondary learners in life sciences: a case study
- Authors: Josua, Helena Megameno N
- Date: 2010
- Subjects: Writing skills English language -- Study and teaching (Secondary) -- South Africa English language -- Writing -- Study and teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1570 , http://hdl.handle.net/10962/d1003452
- Description: Learners in the Junior Secondary Phase (Grades 8 to 10) are often required to answer open-ended questions which require a response in the form of an explanation. As frequently reported in the external examiners' reports of Life Sciences, learners do not write adequate explanations as responses to explanatory questions. This thesis reports on action research based on my experience as a Life Sciences teacher trying to address this problem. Therefore, the purpose of this study was to develop suitable, manageable and effective strategies that I could implement in order to improve my teaching of explanation writing skills of in the Junior Secondary school learners with a view to enhance curriculum content knowledge in Life Sciences. The intervention was carried out in a Grade 10 Life Sciences class which consisted of 35 learners. The first cycle consisted of seven lessons carried out over two weeks in normal school time. The main sources of data from my lesson interventions were the learners' written work, their journal entries, the researcher's journal, the field notes from the non-participant observer and interviews with two focus groups. Both the interviews and the lessons were recorded and transcribed. The research data reveals that the ability of the Junior Secondary learners to write explanations was hindered by language problems. In addition, a lack of integration of language issues into the subject content was a contributing factor to their inadequate writing skills. Spelling errors and lack of expression in English second language contribute to the problem of writing good explanations. The data has also revealed that learners‟ writing skills can be improved by implementing suitable teaching strategies, such as the curriculum cycle as proposed by Gibbons (2002). The curriculum cycle can be modified to fit the learners' needs and the real teaching situation. The amount of practice required to master the skill of writing in the genre of explanations should be considered.
- Full Text:
- Date Issued: 2010
- Authors: Josua, Helena Megameno N
- Date: 2010
- Subjects: Writing skills English language -- Study and teaching (Secondary) -- South Africa English language -- Writing -- Study and teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1570 , http://hdl.handle.net/10962/d1003452
- Description: Learners in the Junior Secondary Phase (Grades 8 to 10) are often required to answer open-ended questions which require a response in the form of an explanation. As frequently reported in the external examiners' reports of Life Sciences, learners do not write adequate explanations as responses to explanatory questions. This thesis reports on action research based on my experience as a Life Sciences teacher trying to address this problem. Therefore, the purpose of this study was to develop suitable, manageable and effective strategies that I could implement in order to improve my teaching of explanation writing skills of in the Junior Secondary school learners with a view to enhance curriculum content knowledge in Life Sciences. The intervention was carried out in a Grade 10 Life Sciences class which consisted of 35 learners. The first cycle consisted of seven lessons carried out over two weeks in normal school time. The main sources of data from my lesson interventions were the learners' written work, their journal entries, the researcher's journal, the field notes from the non-participant observer and interviews with two focus groups. Both the interviews and the lessons were recorded and transcribed. The research data reveals that the ability of the Junior Secondary learners to write explanations was hindered by language problems. In addition, a lack of integration of language issues into the subject content was a contributing factor to their inadequate writing skills. Spelling errors and lack of expression in English second language contribute to the problem of writing good explanations. The data has also revealed that learners‟ writing skills can be improved by implementing suitable teaching strategies, such as the curriculum cycle as proposed by Gibbons (2002). The curriculum cycle can be modified to fit the learners' needs and the real teaching situation. The amount of practice required to master the skill of writing in the genre of explanations should be considered.
- Full Text:
- Date Issued: 2010
Beyond Afrocentricism and Orientalism contemporary representations of transnational identities in the works of Nontsikelelo "Lolo" Veleko and Tracy Payne
- Authors: Pycroft, Hayley
- Date: 2010
- Subjects: Veleko, Nontsikelelo -- Criticism and interpretation Payne, Tracy, 1965- -- Criticism and interpretation Afrocentrism Orientalism Art and race Art and society Gender identity in art Art -- Political aspects Photographers -- South Africa Painters -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2420 , http://hdl.handle.net/10962/d1002216
- Description: South African photographer Nontsikelelo “Lolo” Veleko and South African painter Tracy Payne explore different ways of communicating African realities. The visual imagery of these two artists focuses a lot on movement, challenging the rigidity of boundaries set by Western social constructs. In their work, Veleko and Payne critique the limitations of terms such as “authenticity.” It is extremely difficult to portray shifting notions of contemporary African identity in light of the stain of colonial philosophies which have, in times past, exoticised and appropriated the African body and ascribed conventions of “authenticity” to African representations. Undermining the burden of Western boundaries1, Veleko and Payne redefine what it means to operate in Africa today. Veleko seeks additional cultural realities to complicate her identity as a woman living in Africa while Payne uses concepts of movement to question the validity of structures which advocate an either/ or binary such as “East” and “West” and “masculinity” and “femininity”. By subtly merging aspects of these binaries in their representations, Veleko and Payne bring transnational possibilities to light by undermining the restrictions inscribed in the social and political history of (South) Africa with regard to collective and individual identities. Constructs of gender have contributed to a heightened sense of “African” “masculinity,” forming a stereotype of the African body which is difficult to break free from. Considering the notion of transnationalism and the issue of moving beyond boundaries, borrowing aspects of different cultures in attempt to better define a sense of self, Veleko and Payne engage in the sampling of different lifestyles and perspectives to better define their individualities. This thesis seeks to provide an analysis of the visual language used by Veleko and Payne to promote fluid “African” identities.
- Full Text:
- Date Issued: 2010
- Authors: Pycroft, Hayley
- Date: 2010
- Subjects: Veleko, Nontsikelelo -- Criticism and interpretation Payne, Tracy, 1965- -- Criticism and interpretation Afrocentrism Orientalism Art and race Art and society Gender identity in art Art -- Political aspects Photographers -- South Africa Painters -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2420 , http://hdl.handle.net/10962/d1002216
- Description: South African photographer Nontsikelelo “Lolo” Veleko and South African painter Tracy Payne explore different ways of communicating African realities. The visual imagery of these two artists focuses a lot on movement, challenging the rigidity of boundaries set by Western social constructs. In their work, Veleko and Payne critique the limitations of terms such as “authenticity.” It is extremely difficult to portray shifting notions of contemporary African identity in light of the stain of colonial philosophies which have, in times past, exoticised and appropriated the African body and ascribed conventions of “authenticity” to African representations. Undermining the burden of Western boundaries1, Veleko and Payne redefine what it means to operate in Africa today. Veleko seeks additional cultural realities to complicate her identity as a woman living in Africa while Payne uses concepts of movement to question the validity of structures which advocate an either/ or binary such as “East” and “West” and “masculinity” and “femininity”. By subtly merging aspects of these binaries in their representations, Veleko and Payne bring transnational possibilities to light by undermining the restrictions inscribed in the social and political history of (South) Africa with regard to collective and individual identities. Constructs of gender have contributed to a heightened sense of “African” “masculinity,” forming a stereotype of the African body which is difficult to break free from. Considering the notion of transnationalism and the issue of moving beyond boundaries, borrowing aspects of different cultures in attempt to better define a sense of self, Veleko and Payne engage in the sampling of different lifestyles and perspectives to better define their individualities. This thesis seeks to provide an analysis of the visual language used by Veleko and Payne to promote fluid “African” identities.
- Full Text:
- Date Issued: 2010
Metallophthalocyanines as electrocatalysts and superoxide dismutase mimics
- Authors: Matemadombo, Fungisai
- Date: 2010
- Subjects: Mimicry (Chemistry) Electrocatalysis Superoxide dismutase Electrochemistry Phthalocyanines
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4325 , http://hdl.handle.net/10962/d1004985
- Description: Syntheses, spectral, electrochemical, and spectroelectrochemical studies of iron, cobalt, and manganese phthalocyanines are reported. The novel coordination of cobalt tetracarboxy metallophthalocyanine to an electrode premodified with aryl radicals and its use in the detection of thiocyanate are reported. This work describes the catalytic activity of cobalt phthalocyanine (CoPc) derivatives adsorbed onto glassy carbon electrodes for the electrocatalytical detection of nitrite, Lcysteine, and melatonin. The modified electrodes efficiently detected nitrite. The CoPc derivative modified electrodes proficiently detected L-cysteine whereas an un-modified electrode could not. This work presents the innovative electrochemical detection of melatonin using electrodes adsorbed with CoPc derivatives. These electrodes detected melatonin at more favorable electrochemical parameters relative to an un-modified gold electrode. The limits of melatonin detection of the modified electrodes lay in the 10⁻⁷ to 10⁻⁶ M region. The modified electrodes accurately detected capsule melatonin concentrations as specified by the supplier and could differentiate between a mixture of melatonin, tryptophan, and ascorbic acid. They reliably detected nitrite, L-cysteine, and melatonin in the 10⁻⁴ to 10⁻² M region. Metallophthalocyanine complexes substituted with thio groups were employed as self assembled monolayers (SAMs). Voltammetry, impedance, atomic force microscopy, and scanning electrochemical microscopy proved that the SAMs all act as selective and efficient barriers to ion permeability. All the SAMs in this work can be used as effective electrochemical sensors of nitrite and L-cysteine in the 10⁻⁴ to 10⁻² M region with competitive limits of detection whereas an un-modified electrode cannot detect Lcysteine. The manganese phthalocyanine SAM modified electrodes are arguably better nitrite and L-cysteine electrocatalysts relative to their iron and cobalt counterparts. Manganese phthalocyanines were used as superoxide dismutase (SOD) mimics. All manganese phthalocyanine complexes in this work acted as SOD mimics in an enzymatic system of superoxide production. From cellular studies, complexes 6d, 6e, 8d, 8e act as intracellular SOD mimics and are without significantly high cellular toxicity.
- Full Text:
- Date Issued: 2010
- Authors: Matemadombo, Fungisai
- Date: 2010
- Subjects: Mimicry (Chemistry) Electrocatalysis Superoxide dismutase Electrochemistry Phthalocyanines
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4325 , http://hdl.handle.net/10962/d1004985
- Description: Syntheses, spectral, electrochemical, and spectroelectrochemical studies of iron, cobalt, and manganese phthalocyanines are reported. The novel coordination of cobalt tetracarboxy metallophthalocyanine to an electrode premodified with aryl radicals and its use in the detection of thiocyanate are reported. This work describes the catalytic activity of cobalt phthalocyanine (CoPc) derivatives adsorbed onto glassy carbon electrodes for the electrocatalytical detection of nitrite, Lcysteine, and melatonin. The modified electrodes efficiently detected nitrite. The CoPc derivative modified electrodes proficiently detected L-cysteine whereas an un-modified electrode could not. This work presents the innovative electrochemical detection of melatonin using electrodes adsorbed with CoPc derivatives. These electrodes detected melatonin at more favorable electrochemical parameters relative to an un-modified gold electrode. The limits of melatonin detection of the modified electrodes lay in the 10⁻⁷ to 10⁻⁶ M region. The modified electrodes accurately detected capsule melatonin concentrations as specified by the supplier and could differentiate between a mixture of melatonin, tryptophan, and ascorbic acid. They reliably detected nitrite, L-cysteine, and melatonin in the 10⁻⁴ to 10⁻² M region. Metallophthalocyanine complexes substituted with thio groups were employed as self assembled monolayers (SAMs). Voltammetry, impedance, atomic force microscopy, and scanning electrochemical microscopy proved that the SAMs all act as selective and efficient barriers to ion permeability. All the SAMs in this work can be used as effective electrochemical sensors of nitrite and L-cysteine in the 10⁻⁴ to 10⁻² M region with competitive limits of detection whereas an un-modified electrode cannot detect Lcysteine. The manganese phthalocyanine SAM modified electrodes are arguably better nitrite and L-cysteine electrocatalysts relative to their iron and cobalt counterparts. Manganese phthalocyanines were used as superoxide dismutase (SOD) mimics. All manganese phthalocyanine complexes in this work acted as SOD mimics in an enzymatic system of superoxide production. From cellular studies, complexes 6d, 6e, 8d, 8e act as intracellular SOD mimics and are without significantly high cellular toxicity.
- Full Text:
- Date Issued: 2010