African mead biotechnology and indigenous knowledge systems in iQhilika process development
- Authors: Cambray, Garth Anton
- Date: 2005
- Subjects: Biotechnology Indigenous peoples -- Africa Ethnoscience -- Africa Mead -- Africa Brewing -- Microbiology Honeybee Honey
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3929 , http://hdl.handle.net/10962/d1003988
- Description: While the production of mead, a fermented honey beverage, has declined in popularity around the world in recent centuries, a substantial mead industry continues to exist in Africa with an estimated annual production of 1 to 1.7 billion litres. This is largely an ‘invisible industry’, and has functioned outside the formal economy due to proscription of indigenous beverages during colonial times. The traditional African mead industry is, however, also now under pressure due to the environmental degradation of scarce natural ingredients, urbanisation and loss of indigenous knowledge systems (IKS) and, with time, the beverage will likely follow the declining trend of mead consumption observed elsewhere. An analysis of early reports of African mead production suggested that the Khoi-San, among the earliest inhabitants of the continent, are the originators of the mead making techniques which use fibrous plant materials derived from specific plant species, to facilitate mead fermentation in some way. The Eastern Cape represents a region with a large body of Khoi-San IKS preserved in their descendants among the Afrikaans and Xhosa populations. A survey to establish a baseline of mead-making technology in the Eastern Cape was undertaken, and involved interviewing traditional mead makers across an area of roughly 100 000 km2, showing that the mead, iQhilika(Xhosa) Kari (Khoi-San/Afrikaans), is produced using a very similar process throughout the region. This involves the roots of a Trichodiadema sp. plant (imoela – Xhosa, karimoer – Afrikaans/Khoi-San), honey, extract of brood and/or pollen and water. Various other fruit sugar sources were also found to be added at times producing seasonal beverages with unique organoleptic properties. A model traditional iQhilika production operation was investigated in order to describe the main features of the process. Biomass immobilised on Trichodiadema root segments was found to be distributed evenly through the profile of the bioreactor resulting in a well mixed fermentation and a productivity of 0.74 g EtOH/l/h. In the initial stages of fermentation, the ethanol yield was highest in the mid-regions of the bioreactor, but with time the regions closer to the surface, which had atmospheric contact had a higher yield. This phenomenon was attributed to aerobic fatty acid synthesis which allowed the yeast close to the surface to function more efficiently despite rising ethanol concentrations. The mead contained 44.25 g/l (7 % volume) ethanol produced in a fermentation time of 43.5 h. Yeast biomass in the traditional process was either immobilised in the form of flocs or attached to the Trichodiadema intonsum support. Electron microscopy revealed that the cells were covered in a layer of extra-cellular polymeric substance apparently assisting the immobilization, and which was populated by a consortium of yeasts and bacteria. Yeasts isolated from iQhilika brewed in two regions separated by 350 km were found to be very closely related Saccharomyces cerevisiae strains as determined by molecular genetic analysis. The traditional beverage was found to contain populations of Lactic acid bacteria (LAB), which are known spoilage organisms in other beverages. Spoilage characteristics of these organisms matched descriptions of spoilage provided by the IKS survey. Other possibly beneficial LAB, which may contribute useful flavour compounds, were also found to be present in the system. The basic functional aspects of the traditional process were used to design a continuous bench-scale tower bioreactor and process development was based on the IKS survey. This consisted of a packed bed bioreactor, consisting of 2 mm3 T. intonsum root segments, immobilising a novel Saccharomyces cerevisiae strain isolated from a traditional batch of iQhilika. The bioreactor performed well with a yield of close to the theoretical maximum and an ethanol productivity of 3.45 g EtOH/l/h. The parameters of the 5.6 l/d bench-scale bioreactor were used to design a full-scale production bioreactor with a planned maximum output of 330 l/d. This bioreactor had a productivity of 0.19 g EtOH/l/h. The organoleptic properties of the product produced were considered by a taste panel to be better than those of the product of the bench-scale tower bioreactor. This research was based on the development of IKS which imposed a number of constraints and obligations on the project to ensure environmental, and social, in addition to financial viability of the scale-up operation. Makana Meadery was established in partnership with Rhodes University as an empowerment company which, in addition to undertaking the commercialisation of the iQhilika process, would also develop methods for the production of scarce ingredients traditionally unsustainably sourced from fragile ecosystems, provide beekeeping training and the manufacture of beehives.
- Full Text:
- Date Issued: 2005
- Authors: Cambray, Garth Anton
- Date: 2005
- Subjects: Biotechnology Indigenous peoples -- Africa Ethnoscience -- Africa Mead -- Africa Brewing -- Microbiology Honeybee Honey
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3929 , http://hdl.handle.net/10962/d1003988
- Description: While the production of mead, a fermented honey beverage, has declined in popularity around the world in recent centuries, a substantial mead industry continues to exist in Africa with an estimated annual production of 1 to 1.7 billion litres. This is largely an ‘invisible industry’, and has functioned outside the formal economy due to proscription of indigenous beverages during colonial times. The traditional African mead industry is, however, also now under pressure due to the environmental degradation of scarce natural ingredients, urbanisation and loss of indigenous knowledge systems (IKS) and, with time, the beverage will likely follow the declining trend of mead consumption observed elsewhere. An analysis of early reports of African mead production suggested that the Khoi-San, among the earliest inhabitants of the continent, are the originators of the mead making techniques which use fibrous plant materials derived from specific plant species, to facilitate mead fermentation in some way. The Eastern Cape represents a region with a large body of Khoi-San IKS preserved in their descendants among the Afrikaans and Xhosa populations. A survey to establish a baseline of mead-making technology in the Eastern Cape was undertaken, and involved interviewing traditional mead makers across an area of roughly 100 000 km2, showing that the mead, iQhilika(Xhosa) Kari (Khoi-San/Afrikaans), is produced using a very similar process throughout the region. This involves the roots of a Trichodiadema sp. plant (imoela – Xhosa, karimoer – Afrikaans/Khoi-San), honey, extract of brood and/or pollen and water. Various other fruit sugar sources were also found to be added at times producing seasonal beverages with unique organoleptic properties. A model traditional iQhilika production operation was investigated in order to describe the main features of the process. Biomass immobilised on Trichodiadema root segments was found to be distributed evenly through the profile of the bioreactor resulting in a well mixed fermentation and a productivity of 0.74 g EtOH/l/h. In the initial stages of fermentation, the ethanol yield was highest in the mid-regions of the bioreactor, but with time the regions closer to the surface, which had atmospheric contact had a higher yield. This phenomenon was attributed to aerobic fatty acid synthesis which allowed the yeast close to the surface to function more efficiently despite rising ethanol concentrations. The mead contained 44.25 g/l (7 % volume) ethanol produced in a fermentation time of 43.5 h. Yeast biomass in the traditional process was either immobilised in the form of flocs or attached to the Trichodiadema intonsum support. Electron microscopy revealed that the cells were covered in a layer of extra-cellular polymeric substance apparently assisting the immobilization, and which was populated by a consortium of yeasts and bacteria. Yeasts isolated from iQhilika brewed in two regions separated by 350 km were found to be very closely related Saccharomyces cerevisiae strains as determined by molecular genetic analysis. The traditional beverage was found to contain populations of Lactic acid bacteria (LAB), which are known spoilage organisms in other beverages. Spoilage characteristics of these organisms matched descriptions of spoilage provided by the IKS survey. Other possibly beneficial LAB, which may contribute useful flavour compounds, were also found to be present in the system. The basic functional aspects of the traditional process were used to design a continuous bench-scale tower bioreactor and process development was based on the IKS survey. This consisted of a packed bed bioreactor, consisting of 2 mm3 T. intonsum root segments, immobilising a novel Saccharomyces cerevisiae strain isolated from a traditional batch of iQhilika. The bioreactor performed well with a yield of close to the theoretical maximum and an ethanol productivity of 3.45 g EtOH/l/h. The parameters of the 5.6 l/d bench-scale bioreactor were used to design a full-scale production bioreactor with a planned maximum output of 330 l/d. This bioreactor had a productivity of 0.19 g EtOH/l/h. The organoleptic properties of the product produced were considered by a taste panel to be better than those of the product of the bench-scale tower bioreactor. This research was based on the development of IKS which imposed a number of constraints and obligations on the project to ensure environmental, and social, in addition to financial viability of the scale-up operation. Makana Meadery was established in partnership with Rhodes University as an empowerment company which, in addition to undertaking the commercialisation of the iQhilika process, would also develop methods for the production of scarce ingredients traditionally unsustainably sourced from fragile ecosystems, provide beekeeping training and the manufacture of beehives.
- Full Text:
- Date Issued: 2005
Aspects of the ecology and management of the Soupfin shark (Galeorhinus galeus) in South Africa
- Authors: McCord, Meaghen Erica
- Date: 2005
- Subjects: Soupfin shark -- South Africa , Soupfin shark -- Ecology -- South Africa , Fishery management -- South Africa , Shark fisheries -- Management -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5223 , http://hdl.handle.net/10962/d1005066 , Soupfin shark -- South Africa , Soupfin shark -- Ecology -- South Africa , Fishery management -- South Africa , Shark fisheries -- Management -- South Africa
- Description: Global trends in teleost fisheries indicate significant population declines. Thus, alternative fisheries are being developed to meet the growing economic and nutritional demands of the expanding human population. Recently, it has been established that elasmobranch fisheries may fulfill these demands. As many elasmobranchs possess life-history characteristics that make them particularly vulnerable to overfishing, it is imperative to develop management strategies prior to the inception of these fisheries to ensure sustainable resource utilisation. In South Africa, elasmobranchs have been commercially exploited since the 1930s. Although generally considered an under-exploited resource, the potential for growth within these fisheries has been recognized. In 2005, the commercial shark fishery will undergo a transition from medium to long-term rights allocations. This represents an ideal opportunity for scientists and managers to develop precautionary species-specific management plans for commercially exploitable elasmobranch species. The soupfin shark (Galeorhinus galeus) is one of the principal target species in South Africa’s shark fisheries. Given its inherent susceptibility to overexploitation, G. galeus was selected as a management priority by South Africa’s regional fisheries organisation. The purpose of this study was to examine and describe the stock status of G. galeus in South Africa, and to develop a precautionary fishery management plan to ensure the sustainability of this resource. Age, growth, and mortality calculations for G. galeus were made from research survey data collected between 1996 and 1999. A small sample size precluded independent analyses of females. The maximum recorded age for G. galeus was 33 years. Estimated von Bertalanffy growth parameters from observed length-at-age for males and combined sexes were: L∞ 1542.8 mm TL, K 0.21 year⁻¹ , t₀ -2.79 year⁻¹ and L∞ 1560.3 mm TL, K 0.19 year¹, t₀ -3.03 year⁻¹, respectively. The age-at-50% maturity was determined to be 6 years, corresponding to 1011 mm TL for males and 1100 mm TL for combined sexes. Natural mortality was calculated as 0.126 yr⁻¹. The rate of instantaneous total mortality was calculated as 0.27 yr⁻¹. Catch trend analysis showed that catches and CPUE of G. galeus are increasing in the demersal longline fishery, and decreasing in the handline fishery. Decreasing catches and CPUE were observed in fishery-independent research survey data. The status of the soupfin shark stock was modelled using per-recruit analysis. The SB/R model indicated the soupfin shark is being optimally exploited and spawner biomass is at 43% of preexploitation levels. Current fishing levels ( F = 0.14 yr⁻¹) approximate the Fsb₄₀ level (F = 0.17 yr¹); thus, an increase in fishing pressure may lead to stock collapse. It was determined that the current age-at-capture (7.9 years) should be increased to 10 years, or 1420 mm TL, to maximize yield and minimize the possibility of recruitment failure. The results of this study indicate a need for immediate scientific and management intervention in South Africa’s soupfin shark fishery. An assessment report and fishery management plan for G. galeus was compiled, and several management options were proposed. These include the implementation of licence and size restrictions, as well as seasonal/area closures. The potential for an experimental gillnet fishery should be investigated.
- Full Text:
- Date Issued: 2005
- Authors: McCord, Meaghen Erica
- Date: 2005
- Subjects: Soupfin shark -- South Africa , Soupfin shark -- Ecology -- South Africa , Fishery management -- South Africa , Shark fisheries -- Management -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5223 , http://hdl.handle.net/10962/d1005066 , Soupfin shark -- South Africa , Soupfin shark -- Ecology -- South Africa , Fishery management -- South Africa , Shark fisheries -- Management -- South Africa
- Description: Global trends in teleost fisheries indicate significant population declines. Thus, alternative fisheries are being developed to meet the growing economic and nutritional demands of the expanding human population. Recently, it has been established that elasmobranch fisheries may fulfill these demands. As many elasmobranchs possess life-history characteristics that make them particularly vulnerable to overfishing, it is imperative to develop management strategies prior to the inception of these fisheries to ensure sustainable resource utilisation. In South Africa, elasmobranchs have been commercially exploited since the 1930s. Although generally considered an under-exploited resource, the potential for growth within these fisheries has been recognized. In 2005, the commercial shark fishery will undergo a transition from medium to long-term rights allocations. This represents an ideal opportunity for scientists and managers to develop precautionary species-specific management plans for commercially exploitable elasmobranch species. The soupfin shark (Galeorhinus galeus) is one of the principal target species in South Africa’s shark fisheries. Given its inherent susceptibility to overexploitation, G. galeus was selected as a management priority by South Africa’s regional fisheries organisation. The purpose of this study was to examine and describe the stock status of G. galeus in South Africa, and to develop a precautionary fishery management plan to ensure the sustainability of this resource. Age, growth, and mortality calculations for G. galeus were made from research survey data collected between 1996 and 1999. A small sample size precluded independent analyses of females. The maximum recorded age for G. galeus was 33 years. Estimated von Bertalanffy growth parameters from observed length-at-age for males and combined sexes were: L∞ 1542.8 mm TL, K 0.21 year⁻¹ , t₀ -2.79 year⁻¹ and L∞ 1560.3 mm TL, K 0.19 year¹, t₀ -3.03 year⁻¹, respectively. The age-at-50% maturity was determined to be 6 years, corresponding to 1011 mm TL for males and 1100 mm TL for combined sexes. Natural mortality was calculated as 0.126 yr⁻¹. The rate of instantaneous total mortality was calculated as 0.27 yr⁻¹. Catch trend analysis showed that catches and CPUE of G. galeus are increasing in the demersal longline fishery, and decreasing in the handline fishery. Decreasing catches and CPUE were observed in fishery-independent research survey data. The status of the soupfin shark stock was modelled using per-recruit analysis. The SB/R model indicated the soupfin shark is being optimally exploited and spawner biomass is at 43% of preexploitation levels. Current fishing levels ( F = 0.14 yr⁻¹) approximate the Fsb₄₀ level (F = 0.17 yr¹); thus, an increase in fishing pressure may lead to stock collapse. It was determined that the current age-at-capture (7.9 years) should be increased to 10 years, or 1420 mm TL, to maximize yield and minimize the possibility of recruitment failure. The results of this study indicate a need for immediate scientific and management intervention in South Africa’s soupfin shark fishery. An assessment report and fishery management plan for G. galeus was compiled, and several management options were proposed. These include the implementation of licence and size restrictions, as well as seasonal/area closures. The potential for an experimental gillnet fishery should be investigated.
- Full Text:
- Date Issued: 2005
Developing an environmental education strategy framework: a case study of the Endangered Wildlife Trust (EWT)
- Authors: O'Grady, Janis
- Date: 2005
- Subjects: Endangered Wildlife Trust Environmental education -- South Africa Conservation of natural resources -- South Africa Biodiversity -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1494 , http://hdl.handle.net/10962/d1003375
- Description: The study focused on the development of an environmental education (EE) strategy framework in the Endangered Wildlife Trust (EWT) of South Africa. Evidence shows that the roles of conservation and biodiversity education could potentially be merged towards producing a practical strategy, beneficial to the organisation and its individual staff members. Questionnaires, interviews and the individual perceptions of staff members, as well as the analysis of relevant documents, suggested that the potential for the practice of EE towards the development of an EE strategy within the organisation is substantial. EWT staff members can contribute towards a change in the way that South Africans think about conservation and nature. Environmental ethics need to be promoted and understood by all. Within the EWT, environmental education activities are in place and diverse, yet they lack any form of monitoring and evaluation. The Trust is already practicing a form of EE but the potential to do more and the opportunities for expansion are unlimited.
- Full Text:
- Date Issued: 2005
- Authors: O'Grady, Janis
- Date: 2005
- Subjects: Endangered Wildlife Trust Environmental education -- South Africa Conservation of natural resources -- South Africa Biodiversity -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1494 , http://hdl.handle.net/10962/d1003375
- Description: The study focused on the development of an environmental education (EE) strategy framework in the Endangered Wildlife Trust (EWT) of South Africa. Evidence shows that the roles of conservation and biodiversity education could potentially be merged towards producing a practical strategy, beneficial to the organisation and its individual staff members. Questionnaires, interviews and the individual perceptions of staff members, as well as the analysis of relevant documents, suggested that the potential for the practice of EE towards the development of an EE strategy within the organisation is substantial. EWT staff members can contribute towards a change in the way that South Africans think about conservation and nature. Environmental ethics need to be promoted and understood by all. Within the EWT, environmental education activities are in place and diverse, yet they lack any form of monitoring and evaluation. The Trust is already practicing a form of EE but the potential to do more and the opportunities for expansion are unlimited.
- Full Text:
- Date Issued: 2005
Development of the South African monetary banking sector and money market
- Authors: Patel, Aadil Suleman
- Date: 2005
- Subjects: South African Reserve Bank , Banks and banking -- South Africa , Money market -- South Africa , Economic development -- South Africa , Monetary policy -- South Africa , South Africa -- Economic conditions , Financial institutions -- South Africa , Money -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:997 , http://hdl.handle.net/10962/d1002732 , South African Reserve Bank , Banks and banking -- South Africa , Money market -- South Africa , Economic development -- South Africa , Monetary policy -- South Africa , South Africa -- Economic conditions , Financial institutions -- South Africa , Money -- South Africa
- Description: This thesis presents a theoretical analysis of developments in the South African monetary banking sector and money market. In the first section, evolution of the political, social and economic environments over the past few decades are discussed to provide the reader with an idea of some factors responsible for the underdeveloped nature of this market. It has been argued that the domestic political and economic landscape is relatively stable. Nevertheless, factors such as Zimbabwe’s political and ensuing economic turmoil, coupled with numerous financial crises in other developing nations have had negative consequences on domestic financial market development and economic growth. The current state of monetary policy is also analysed, within the economic environment, and various policy considerations have been put forth concerning the inflation targeting policy. The thesis then goes on to scrutinise the statutory and institutional environments within which the monetary banking institutions operate. Recent changes in the regulations governing the operations of these institutions are identified, together with the consequences of such laws on banking institutions and possible amendments have been suggested. In particular, a system of Asset Based Reserve Requirements (ABRR) has been recommended, in place of the current cash reserve requirement, to ensure regulators create a level playing field in the financial sector. The system can also provide authorities with the necessary control required to direct funds to the most desirable sectors of the economy. Development of the interbank market and the effect of reduced banking competition on the efficacy of the South African Reserve Bank’s refinancing operations and inflation targeting policy are also considered. Finally, the thesis analyses some effects of financial development on the South African economy, and whether it is in the best interests of the country to pursue financial reforms with such vigour. While financial development may bring South Africa closer to international standards of best practice, the timing and extent of the reforms will be critical to guarantee success.
- Full Text:
- Date Issued: 2005
- Authors: Patel, Aadil Suleman
- Date: 2005
- Subjects: South African Reserve Bank , Banks and banking -- South Africa , Money market -- South Africa , Economic development -- South Africa , Monetary policy -- South Africa , South Africa -- Economic conditions , Financial institutions -- South Africa , Money -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:997 , http://hdl.handle.net/10962/d1002732 , South African Reserve Bank , Banks and banking -- South Africa , Money market -- South Africa , Economic development -- South Africa , Monetary policy -- South Africa , South Africa -- Economic conditions , Financial institutions -- South Africa , Money -- South Africa
- Description: This thesis presents a theoretical analysis of developments in the South African monetary banking sector and money market. In the first section, evolution of the political, social and economic environments over the past few decades are discussed to provide the reader with an idea of some factors responsible for the underdeveloped nature of this market. It has been argued that the domestic political and economic landscape is relatively stable. Nevertheless, factors such as Zimbabwe’s political and ensuing economic turmoil, coupled with numerous financial crises in other developing nations have had negative consequences on domestic financial market development and economic growth. The current state of monetary policy is also analysed, within the economic environment, and various policy considerations have been put forth concerning the inflation targeting policy. The thesis then goes on to scrutinise the statutory and institutional environments within which the monetary banking institutions operate. Recent changes in the regulations governing the operations of these institutions are identified, together with the consequences of such laws on banking institutions and possible amendments have been suggested. In particular, a system of Asset Based Reserve Requirements (ABRR) has been recommended, in place of the current cash reserve requirement, to ensure regulators create a level playing field in the financial sector. The system can also provide authorities with the necessary control required to direct funds to the most desirable sectors of the economy. Development of the interbank market and the effect of reduced banking competition on the efficacy of the South African Reserve Bank’s refinancing operations and inflation targeting policy are also considered. Finally, the thesis analyses some effects of financial development on the South African economy, and whether it is in the best interests of the country to pursue financial reforms with such vigour. While financial development may bring South Africa closer to international standards of best practice, the timing and extent of the reforms will be critical to guarantee success.
- Full Text:
- Date Issued: 2005
An investigation of instructional leadership in a Namibian teacher training college
- Alexander, Christa Henriette
- Authors: Alexander, Christa Henriette
- Date: 2005
- Subjects: Windhoek College of Education Educational leadership -- Namibia Education -- Namibia Teachers -- Training of -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1634 , http://hdl.handle.net/10962/d1003516
- Description: This thesis investigates how instructional leaders at the Windhoek College of Education (in Namibia) make sense of their roles. The Windhoek College of Education (WCE) was selected for this study because that is where I work, therefore it would be easy to observe some of the responses provided by the interviewees. It was also observed that instructional leadership is little researched in Namibia and hence study would contribute towards understanding the various perceptions that instructional leaders have of their roles. There is a need for information about the skills and tasks required to support practices of instructional leadership so that the best possible instruction can be provided. The thesis examines and presents such skills. A qualitative research framework, in particular an interpretative approach was used for the study. As my research is concerned with people’s perceptions, it is located in the interpretative paradigm. Semi-structured, open-ended interview questions were asked in order to gather information on how the participants make meaning of their roles as instructional leaders. The sample for the study consisted of eleven instructional leaders over different levels, i.e., executive leaders, leaders on middle-management level and leaders on classroom-instructional level. The findings indicated a narrow view of instructional leadership at the college. Factors contributing to this narrowness are addressed, e.g., the way concepts such as delegation, guidance and monitoring/supervision are perceived. The findings also addressed certain expectations that are needed from instructional leaders in order to ensure efficiency in their practice. The study concludes by recommending alternative, expansive ways of thinking about instructional leadership.
- Full Text:
- Date Issued: 2005
- Authors: Alexander, Christa Henriette
- Date: 2005
- Subjects: Windhoek College of Education Educational leadership -- Namibia Education -- Namibia Teachers -- Training of -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1634 , http://hdl.handle.net/10962/d1003516
- Description: This thesis investigates how instructional leaders at the Windhoek College of Education (in Namibia) make sense of their roles. The Windhoek College of Education (WCE) was selected for this study because that is where I work, therefore it would be easy to observe some of the responses provided by the interviewees. It was also observed that instructional leadership is little researched in Namibia and hence study would contribute towards understanding the various perceptions that instructional leaders have of their roles. There is a need for information about the skills and tasks required to support practices of instructional leadership so that the best possible instruction can be provided. The thesis examines and presents such skills. A qualitative research framework, in particular an interpretative approach was used for the study. As my research is concerned with people’s perceptions, it is located in the interpretative paradigm. Semi-structured, open-ended interview questions were asked in order to gather information on how the participants make meaning of their roles as instructional leaders. The sample for the study consisted of eleven instructional leaders over different levels, i.e., executive leaders, leaders on middle-management level and leaders on classroom-instructional level. The findings indicated a narrow view of instructional leadership at the college. Factors contributing to this narrowness are addressed, e.g., the way concepts such as delegation, guidance and monitoring/supervision are perceived. The findings also addressed certain expectations that are needed from instructional leaders in order to ensure efficiency in their practice. The study concludes by recommending alternative, expansive ways of thinking about instructional leadership.
- Full Text:
- Date Issued: 2005
An investigation into perceptions of learner participation in the governance of secondary schools
- Authors: Nongubo, Mphuthumi J
- Date: 2005
- Subjects: Education and state -- South Africa , School management and organization -- South Africa , Education, Secondary -- South Africa , Student government -- South Africa , Student participation in administration -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2007 , http://hdl.handle.net/10962/d1015747
- Description: The question of learner participation or involvement in school governance has been a thorny issue in South Africa for decades. This study investigated secondary learners’ participation in the governance of their schools through representation by the Representative Council of Learners (RCLs), formerly known as school representative councils (SRCs). The study attempted to find out how learners participation is perceived by both the RCLs and the School Management Teams (SMTs). The study was conducted in five secondary schools in the Eastern Cape townships of Grahamstown. The research participants were members of School Management Teams and Representative Councils of Learners from these schools. The study was oriented in an interpretive paradigm following a qualitative approach. Questionnaires and in-depth semi-structured interviews were used to explore the perceptions of the two groups involved. The Department of Education documents that sanction RCL participation were referred to throughout and especially when analysing the respondents’ views. The main finding of the study is that learner involvement in school governance is still problematic, though it is presently provided for by policies that govern schools, including the South African Schools Act and the Guides for Representative Councils of Learners of 1999, in which their roles are outlined. The findings of the study reveal an indecisive and autocratic mindset among educators regarding the issue of learner involvement in governance and management. Furthermore, the Department of Education documents in place betray a narrow conception of RCL participation in school governance and still display an element of mistrust towards the learners concerning their roles in governance. As a result of these forces, the democratic potential of learner participation is undermined, and RCLs compromised as legitimate stakeholders.
- Full Text:
- Date Issued: 2005
- Authors: Nongubo, Mphuthumi J
- Date: 2005
- Subjects: Education and state -- South Africa , School management and organization -- South Africa , Education, Secondary -- South Africa , Student government -- South Africa , Student participation in administration -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2007 , http://hdl.handle.net/10962/d1015747
- Description: The question of learner participation or involvement in school governance has been a thorny issue in South Africa for decades. This study investigated secondary learners’ participation in the governance of their schools through representation by the Representative Council of Learners (RCLs), formerly known as school representative councils (SRCs). The study attempted to find out how learners participation is perceived by both the RCLs and the School Management Teams (SMTs). The study was conducted in five secondary schools in the Eastern Cape townships of Grahamstown. The research participants were members of School Management Teams and Representative Councils of Learners from these schools. The study was oriented in an interpretive paradigm following a qualitative approach. Questionnaires and in-depth semi-structured interviews were used to explore the perceptions of the two groups involved. The Department of Education documents that sanction RCL participation were referred to throughout and especially when analysing the respondents’ views. The main finding of the study is that learner involvement in school governance is still problematic, though it is presently provided for by policies that govern schools, including the South African Schools Act and the Guides for Representative Councils of Learners of 1999, in which their roles are outlined. The findings of the study reveal an indecisive and autocratic mindset among educators regarding the issue of learner involvement in governance and management. Furthermore, the Department of Education documents in place betray a narrow conception of RCL participation in school governance and still display an element of mistrust towards the learners concerning their roles in governance. As a result of these forces, the democratic potential of learner participation is undermined, and RCLs compromised as legitimate stakeholders.
- Full Text:
- Date Issued: 2005
A case study of stakeholders' perceptions of the management implications of the discipline provisions of the 1996 Schools Act in a rural Eastern Cape high school
- Authors: Luggya, Daniel
- Date: 2005
- Subjects: High school students -- Discipline -- South Africa -- Eastern Cape Discipline of children -- South Africa -- Eastern Cape School discipline -- South Africa -- Eastern Cape Corporal punishment -- South Africa -- Eastern Cape School management and organization -- South Africa -- Eastern Cape School discipline -- Law and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1897 , http://hdl.handle.net/10962/d1006156
- Description: South Africa's education management system has undergone a long history of transformation from the promulgation of the Bantu Education Act of 1953 to the realisation of democracy, and in this context, the South Mrican Schools Act (SASA) of l996. Apartheid legislation and the new democratic legislation have had a profound impact on the education leadership and management of schools, in which authoritarian management practices have been replaced by democratic management practices. However, democratic management practices have not yet had a significant effect in the leadership and management of schools, especially in the schools of previously disadvantaged areas. This thesis seeks to examine perceptions held by education stakeholders in the light of the rights of students as stipulated in the discipline provisions of the Schools Act of 1996, in one of the rural high schools in the Northern Region of the Eastern Cape Province. One of the most important discipline provisions is the ban on corporal punishment in schools. My intention in carrying out this research was not to generalise my findings but to understand the experiences and perceptions of the stakeholders in this school regarding the discipline provisions of the SASA. The data suggest that authoritarian education practices, especially corporal punishment, are still a factor in the maintenance of student discipline in this rural school. Stakeholders still believe in the use of corporal punishment as the only way of maintaining discipline and an orderly environment for teaching and learning. Such beliefs, assumptions and values concerning the use of corporal punishment are held by the principal, teachers, students and parents and have not changed since 1996. Beliefs, assumptions and values on the exclusive use of power by the principal on issues of suspension and expulsion are still being held by the above stakeholders in the school. The vision of the SASA that schools become autonomous institutions with democratic leadership and management practices does not seem to be practical because of the centralisation of power in the hands of the Provincial Head of the Education Department. This centralisation of power denies the principal and other stakeholders of the school the power to decide on crucial matters like the expulsion of misbehaving students, because it is the provincial Head who decides on the seriousness of offences committed by misbehaving students and subsequent expulsions. Apart from the location of power in the Provincial Head of the Education Department, the stakeholders of this school are also powerless on expulsion of students, or any other form of punishment because of the implication of the "right" to education in the Bill of Rights in the Constitution of the Republic of South Africa. The education department has to devise programmes that change the beliefs and assumptions of stakeholders on corporal punishment and decision-making on expulsions and suspensions. Unfortunately corporal punishment persists because parents use it in the home and support its use in school. Programmes on alternatives to corporal punishment are required for the smooth implementation of the SASA.
- Full Text:
- Date Issued: 2005
- Authors: Luggya, Daniel
- Date: 2005
- Subjects: High school students -- Discipline -- South Africa -- Eastern Cape Discipline of children -- South Africa -- Eastern Cape School discipline -- South Africa -- Eastern Cape Corporal punishment -- South Africa -- Eastern Cape School management and organization -- South Africa -- Eastern Cape School discipline -- Law and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1897 , http://hdl.handle.net/10962/d1006156
- Description: South Africa's education management system has undergone a long history of transformation from the promulgation of the Bantu Education Act of 1953 to the realisation of democracy, and in this context, the South Mrican Schools Act (SASA) of l996. Apartheid legislation and the new democratic legislation have had a profound impact on the education leadership and management of schools, in which authoritarian management practices have been replaced by democratic management practices. However, democratic management practices have not yet had a significant effect in the leadership and management of schools, especially in the schools of previously disadvantaged areas. This thesis seeks to examine perceptions held by education stakeholders in the light of the rights of students as stipulated in the discipline provisions of the Schools Act of 1996, in one of the rural high schools in the Northern Region of the Eastern Cape Province. One of the most important discipline provisions is the ban on corporal punishment in schools. My intention in carrying out this research was not to generalise my findings but to understand the experiences and perceptions of the stakeholders in this school regarding the discipline provisions of the SASA. The data suggest that authoritarian education practices, especially corporal punishment, are still a factor in the maintenance of student discipline in this rural school. Stakeholders still believe in the use of corporal punishment as the only way of maintaining discipline and an orderly environment for teaching and learning. Such beliefs, assumptions and values concerning the use of corporal punishment are held by the principal, teachers, students and parents and have not changed since 1996. Beliefs, assumptions and values on the exclusive use of power by the principal on issues of suspension and expulsion are still being held by the above stakeholders in the school. The vision of the SASA that schools become autonomous institutions with democratic leadership and management practices does not seem to be practical because of the centralisation of power in the hands of the Provincial Head of the Education Department. This centralisation of power denies the principal and other stakeholders of the school the power to decide on crucial matters like the expulsion of misbehaving students, because it is the provincial Head who decides on the seriousness of offences committed by misbehaving students and subsequent expulsions. Apart from the location of power in the Provincial Head of the Education Department, the stakeholders of this school are also powerless on expulsion of students, or any other form of punishment because of the implication of the "right" to education in the Bill of Rights in the Constitution of the Republic of South Africa. The education department has to devise programmes that change the beliefs and assumptions of stakeholders on corporal punishment and decision-making on expulsions and suspensions. Unfortunately corporal punishment persists because parents use it in the home and support its use in school. Programmes on alternatives to corporal punishment are required for the smooth implementation of the SASA.
- Full Text:
- Date Issued: 2005
Action research on an organization development intervention in a secondary school in the Erongo education region of Namibia
- Authors: Neshila, Selma
- Date: 2005
- Subjects: Education -- Namibia , Educational change -- Namibia , Education and state -- Namibia , School management and organization -- Namibia
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:1418 , http://hdl.handle.net/10962/d1003299
- Description: Organisations that will not, that resist, that cannot, that are incapable, that lack the confidence or that believe it’s not possible to change are likely to stagnate and die (Smith: work in progress). Since independence in March 1990, the new Namibian Government has realized that the quality, efficiency and effectiveness of Namibian schools depends on the ability of teachers and other stakeholders to be innovators and facilitators of change, especially through effective communication, effective meetings, working through conflict, solving problems and making decisions. Organization Development (OD) is an effective, planned change approach for improving organization workgroup processes. Resting on a foundation of values and assumptions about people and organizations, OD promotes collaboration, interdependence and interconnectedness, empowerment, participation and involvement in problem solving and decision-making for all members. Based primarily on a normative, re-educative strategy and secondarily on a rational-empirical strategy, OD assumes that people will change if and when they realize that change is advantageous to them. OD makes use of interventions to determine areas requiring change. The intervention used for my research included a survey-data-feedback (SDF) where data was gathered, analyzed and fed back to the participants. The data was used as a basis for problem solving and training in organizational processes of communication. The case study involved 23 teachers. Journal entries, observation, formal and non-formal interviews as well as focus interviews were used as data collection tools. Participants wanted to see immediate organizational changes thus it was important to remind them that OD is a long-term change approach and that there is no quick fix. Initially, participants were used to the norm of fault finding to determine areas requiring change. However, a year later, during problem solving sessions, I observed collaborative and positive involvement by all participants. Finally, the outcome of the intervention based on the data from the communication workshop and the problem-solving meetings revealed that participants want OD to be institutionalized in all Namibian schools.
- Full Text:
- Date Issued: 2005
- Authors: Neshila, Selma
- Date: 2005
- Subjects: Education -- Namibia , Educational change -- Namibia , Education and state -- Namibia , School management and organization -- Namibia
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:1418 , http://hdl.handle.net/10962/d1003299
- Description: Organisations that will not, that resist, that cannot, that are incapable, that lack the confidence or that believe it’s not possible to change are likely to stagnate and die (Smith: work in progress). Since independence in March 1990, the new Namibian Government has realized that the quality, efficiency and effectiveness of Namibian schools depends on the ability of teachers and other stakeholders to be innovators and facilitators of change, especially through effective communication, effective meetings, working through conflict, solving problems and making decisions. Organization Development (OD) is an effective, planned change approach for improving organization workgroup processes. Resting on a foundation of values and assumptions about people and organizations, OD promotes collaboration, interdependence and interconnectedness, empowerment, participation and involvement in problem solving and decision-making for all members. Based primarily on a normative, re-educative strategy and secondarily on a rational-empirical strategy, OD assumes that people will change if and when they realize that change is advantageous to them. OD makes use of interventions to determine areas requiring change. The intervention used for my research included a survey-data-feedback (SDF) where data was gathered, analyzed and fed back to the participants. The data was used as a basis for problem solving and training in organizational processes of communication. The case study involved 23 teachers. Journal entries, observation, formal and non-formal interviews as well as focus interviews were used as data collection tools. Participants wanted to see immediate organizational changes thus it was important to remind them that OD is a long-term change approach and that there is no quick fix. Initially, participants were used to the norm of fault finding to determine areas requiring change. However, a year later, during problem solving sessions, I observed collaborative and positive involvement by all participants. Finally, the outcome of the intervention based on the data from the communication workshop and the problem-solving meetings revealed that participants want OD to be institutionalized in all Namibian schools.
- Full Text:
- Date Issued: 2005
The politics of humanitarian organizations neutrality and solidarity: the case of the ICRC and MSF during the 1994 Rwandan genocide
- Authors: Delvaux, Denise
- Date: 2005
- Subjects: International Committee of the Red Cross -- History , Médecins sans frontières (Association) , Humanitarian intervention , Neutrality -- Rwanda , Solidarity -- Rwanda , Genocide -- Rwanda -- History -- 20th century , Genocide -- Rwanda , Rwanda -- History -- Civil War, 1994 , Rwanda -- Politics and government
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2769 , http://hdl.handle.net/10962/d1002979 , International Committee of the Red Cross -- History , Médecins sans frontières (Association) , Humanitarian intervention , Neutrality -- Rwanda , Solidarity -- Rwanda , Genocide -- Rwanda -- History -- 20th century , Genocide -- Rwanda , Rwanda -- History -- Civil War, 1994 , Rwanda -- Politics and government
- Description: With the seemingly infinite existence of complex emergencies and the overwhelming presence of humanitarian organizations responding to such crises, it is essential that the assumptions, precepts, and actions of humanitarian organizations be critically examined and understood. The aim of this thesis is to explore differing traditions within humanitarian thought: neutrality and solidarity. In the process, this thesis will determine whether it is possible to maintain clear ideologies in the context of a complex emergency and whether the existence of different humanitarian ideologies results in a dichotomy or polarization of humanitarian action. This study is of great import as it delves into the contemporary literature claiming that humanitarianism is currently in a state of crisis – the unsustainability of competing humanitarian ideologies operating together in a complex emergency. Primary documents from both the International Committee of the Red Cross (ICRC) and Médecins Sans Frontières (MSF) regarding their operations in the 1994 Rwandan complex emergency were examined in order to provide a foundation for the theoretical investigation. Although the ICRC and MSF occupy seemingly polarized positions in the neutrality – solidarity debate, the investigation into their humanitarian activities during the 1994 genocide and the resulting refugee crisis reflected the difficulties of providing relief based upon humanitarian ideals. Due to the complex realities of the 1994 Rwandan crisis, the ideological notions dividing the ICRC and MSF were overshadowed by the simple humanitarian desire to aid those in need.
- Full Text:
- Date Issued: 2005
- Authors: Delvaux, Denise
- Date: 2005
- Subjects: International Committee of the Red Cross -- History , Médecins sans frontières (Association) , Humanitarian intervention , Neutrality -- Rwanda , Solidarity -- Rwanda , Genocide -- Rwanda -- History -- 20th century , Genocide -- Rwanda , Rwanda -- History -- Civil War, 1994 , Rwanda -- Politics and government
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2769 , http://hdl.handle.net/10962/d1002979 , International Committee of the Red Cross -- History , Médecins sans frontières (Association) , Humanitarian intervention , Neutrality -- Rwanda , Solidarity -- Rwanda , Genocide -- Rwanda -- History -- 20th century , Genocide -- Rwanda , Rwanda -- History -- Civil War, 1994 , Rwanda -- Politics and government
- Description: With the seemingly infinite existence of complex emergencies and the overwhelming presence of humanitarian organizations responding to such crises, it is essential that the assumptions, precepts, and actions of humanitarian organizations be critically examined and understood. The aim of this thesis is to explore differing traditions within humanitarian thought: neutrality and solidarity. In the process, this thesis will determine whether it is possible to maintain clear ideologies in the context of a complex emergency and whether the existence of different humanitarian ideologies results in a dichotomy or polarization of humanitarian action. This study is of great import as it delves into the contemporary literature claiming that humanitarianism is currently in a state of crisis – the unsustainability of competing humanitarian ideologies operating together in a complex emergency. Primary documents from both the International Committee of the Red Cross (ICRC) and Médecins Sans Frontières (MSF) regarding their operations in the 1994 Rwandan complex emergency were examined in order to provide a foundation for the theoretical investigation. Although the ICRC and MSF occupy seemingly polarized positions in the neutrality – solidarity debate, the investigation into their humanitarian activities during the 1994 genocide and the resulting refugee crisis reflected the difficulties of providing relief based upon humanitarian ideals. Due to the complex realities of the 1994 Rwandan crisis, the ideological notions dividing the ICRC and MSF were overshadowed by the simple humanitarian desire to aid those in need.
- Full Text:
- Date Issued: 2005
An analysis of the compliance approach used by revenue authorities with specific reference to case selection and risk profiling
- Nel, M J
- Authors: Nel, M J
- Date: 2005
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:878 , http://hdl.handle.net/10962/d1001632
- Description: The vision of probably all revenue authorities is to promote compliance with the provisions of the taxation laws and to ensure responsible enforcement by the revenue authorities, thereby contributing to the economic well being of the country. As with virtually all revenue authorities the South African Revenue Services has to a large extent implemented the self-assessment approach to tax assessments. Because this system depends on this process of selfassessment, an effective risk-based audit approach is required to ensure that tax compliance and responsible enforcement is adhered to. An effective case selection methodology is required for revenue authorities to make informed choices on how best to direct their activities in order to address areas of greatest risk. Given these imperatives, the purpose of this study is to examine the case selection methodologies used by certain revenue authorities, including the South African Revenue Services, and to focus on the key elements of case selection: the use of computerised database systems, industry profiles, third party data and the role of the risk profiler. The results of the study indicate that the case selection methodology of the South African Revenue Services is lacking in some areas. Computerised risk analysis is limited to a certain classes of taxpayers and other aspects of concern are also highlighted in this study.
- Full Text:
- Date Issued: 2005
- Authors: Nel, M J
- Date: 2005
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:878 , http://hdl.handle.net/10962/d1001632
- Description: The vision of probably all revenue authorities is to promote compliance with the provisions of the taxation laws and to ensure responsible enforcement by the revenue authorities, thereby contributing to the economic well being of the country. As with virtually all revenue authorities the South African Revenue Services has to a large extent implemented the self-assessment approach to tax assessments. Because this system depends on this process of selfassessment, an effective risk-based audit approach is required to ensure that tax compliance and responsible enforcement is adhered to. An effective case selection methodology is required for revenue authorities to make informed choices on how best to direct their activities in order to address areas of greatest risk. Given these imperatives, the purpose of this study is to examine the case selection methodologies used by certain revenue authorities, including the South African Revenue Services, and to focus on the key elements of case selection: the use of computerised database systems, industry profiles, third party data and the role of the risk profiler. The results of the study indicate that the case selection methodology of the South African Revenue Services is lacking in some areas. Computerised risk analysis is limited to a certain classes of taxpayers and other aspects of concern are also highlighted in this study.
- Full Text:
- Date Issued: 2005
Geology, structure and mineralization of the Onguati area, Karibib district, central Namibia
- Authors: Viljoen, Wayne
- Date: 2005
- Subjects: Geology -- Namibia -- Karibib , Geology, Structural -- Namibia -- Karibib , Mines and mineral resources -- Namibia -- Karibib
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4964 , http://hdl.handle.net/10962/d1005576 , Geology -- Namibia -- Karibib , Geology, Structural -- Namibia -- Karibib , Mines and mineral resources -- Namibia -- Karibib
- Description: The study area is situated in the Southern Central Zone of the intracontinental Pan-African Damara Orogen, approximately 20km NNE of Navachab Gold Mine in the Karibib district of Namibia. Mesothermal vein systems with Cu-Fe±Au mineralization are hosted by amphibolite facies calcitic and dolomitic marbles belonging to the Navachab Member of the Karibib Formation, and are best developed around the defunct Onguati Copper Mine, Brown Mountain and Western Workings areas. The Onguati study area is located in the saddle region of a moderately-to-gently inclined anticlinorium that experienced significant flattening during NNW-SSE-directed compression. The parallelogram arrangement of ENE- and NNE-trending thrusts and reverse faults that surround the Onguati study area may have developed when the direction of greatest principle subregional stress was oriented WSW-ESE. These structures define part of a Riedel shear system and later faults may have developed in the position of R and P shears respectively. Significant strain partitioning occurred between the ductile calcitic marbles which host the best developed, shear-related vein systems and the more competent dolomitic marbles. The thickness distributions of veins in the marbles of the Onguati Mine, Brown Mountain and Western Workings areas conform to a fractal or power-law distribution, The most intensely mineralized vein systems in the Onguati Mine and Western Workings calcitic marbles share similar low fractal dimensions (D-values) of 0.41 and 0.37 respectively. Veins In the calcitic and dolomitic marbles of the Brown Mountain area and in the dolomitic marbles of Western Workings have elevated D-values (>0.60) and are poorly mineralized. The low D-values «0.40) of the well mineralized vein systems reflect the higher degree of fracture connectivity. These vein systems were capable of efficiently draining and localizing large volumes of mineralizing fluids from crustal-scale structures. A metamorphic devolatization model is proposed where the entire Damaran metasedimentary and meta-volcanic package is seen as a large source area of very low concentrations of Cu, Au and other metals. Localization of deformation into crustal-scale faults and shear zones led to regional-scale hydrothermal fluid flow and focussing into the upstream fracture networks of the Onguati study area. Strong mineralization resulted when fluids encountered the reactive marble lithologies
- Full Text:
- Date Issued: 2005
- Authors: Viljoen, Wayne
- Date: 2005
- Subjects: Geology -- Namibia -- Karibib , Geology, Structural -- Namibia -- Karibib , Mines and mineral resources -- Namibia -- Karibib
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4964 , http://hdl.handle.net/10962/d1005576 , Geology -- Namibia -- Karibib , Geology, Structural -- Namibia -- Karibib , Mines and mineral resources -- Namibia -- Karibib
- Description: The study area is situated in the Southern Central Zone of the intracontinental Pan-African Damara Orogen, approximately 20km NNE of Navachab Gold Mine in the Karibib district of Namibia. Mesothermal vein systems with Cu-Fe±Au mineralization are hosted by amphibolite facies calcitic and dolomitic marbles belonging to the Navachab Member of the Karibib Formation, and are best developed around the defunct Onguati Copper Mine, Brown Mountain and Western Workings areas. The Onguati study area is located in the saddle region of a moderately-to-gently inclined anticlinorium that experienced significant flattening during NNW-SSE-directed compression. The parallelogram arrangement of ENE- and NNE-trending thrusts and reverse faults that surround the Onguati study area may have developed when the direction of greatest principle subregional stress was oriented WSW-ESE. These structures define part of a Riedel shear system and later faults may have developed in the position of R and P shears respectively. Significant strain partitioning occurred between the ductile calcitic marbles which host the best developed, shear-related vein systems and the more competent dolomitic marbles. The thickness distributions of veins in the marbles of the Onguati Mine, Brown Mountain and Western Workings areas conform to a fractal or power-law distribution, The most intensely mineralized vein systems in the Onguati Mine and Western Workings calcitic marbles share similar low fractal dimensions (D-values) of 0.41 and 0.37 respectively. Veins In the calcitic and dolomitic marbles of the Brown Mountain area and in the dolomitic marbles of Western Workings have elevated D-values (>0.60) and are poorly mineralized. The low D-values «0.40) of the well mineralized vein systems reflect the higher degree of fracture connectivity. These vein systems were capable of efficiently draining and localizing large volumes of mineralizing fluids from crustal-scale structures. A metamorphic devolatization model is proposed where the entire Damaran metasedimentary and meta-volcanic package is seen as a large source area of very low concentrations of Cu, Au and other metals. Localization of deformation into crustal-scale faults and shear zones led to regional-scale hydrothermal fluid flow and focussing into the upstream fracture networks of the Onguati study area. Strong mineralization resulted when fluids encountered the reactive marble lithologies
- Full Text:
- Date Issued: 2005
Investigation into the biological removal of sulphate from ethanol distillery wastewater using sulphate-reducing prokaryotes
- Authors: Smuts, Lizl
- Date: 2005
- Subjects: Sewage -- Purification -- Biological treatment , Prokaryotes , Sulfates , Distilleries -- Waste disposal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3941 , http://hdl.handle.net/10962/d1004000 , Sewage -- Purification -- Biological treatment , Prokaryotes , Sulfates , Distilleries -- Waste disposal
- Description: Ethanol production wastewater is known to be toxic, and is not easily biodegradable. It also consists of a variety of coloured components adding to the complex composition of this wastewater. Disposal of this wastewater into water courses is not recommended and yet is performed all over the world. Investigation of this wastewater found that there was a high concentration of sulphate which, in the presence of sulphate-reducing prokaryotes can cause sulphide corrosion of cement. The concentration of sulphate in the wastewater was approximately 2770 mg/L. It was also found that the wastewater pH was very low and discharge of the wastewater into the wastewater treatment works caused a negative impact on the overall quality of the final wastewater discharged to sea. It was found using FISH techniques that there were no sulphate-reducing prokaryotes present in the wastewaters but that a sulphate-reducing population existed on the sewer wall. An anaerobic contact process was designed to treat this wastewater targeting sulphate reduction to sulphide, to be converted into elemental sulphur and to increase the wastewater pH. The process did not achieve this aim and only approximately 20-30 % reduction in sulphate from the wastewater was achieved with little to no change in the pH. A 95 % reduction in sulphate concentration was needed in order to reach acceptable discharge limits. Sulphate reduction could not be carried out, even under ideal laboratory conditions. It was found that the barrier causing the digester failure was the high concentration of phenols present in the wastewater (3.3 g/L) together with the production of high concentrations of volatile fatty acids (on average 13 g acetic/L). These two components are known to cause digester failure, especially phenols, and phenols are usually only degraded by fungal species. It was concluded that the wastewater itself was not amenable to this method of biological treatment.
- Full Text:
- Date Issued: 2005
- Authors: Smuts, Lizl
- Date: 2005
- Subjects: Sewage -- Purification -- Biological treatment , Prokaryotes , Sulfates , Distilleries -- Waste disposal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3941 , http://hdl.handle.net/10962/d1004000 , Sewage -- Purification -- Biological treatment , Prokaryotes , Sulfates , Distilleries -- Waste disposal
- Description: Ethanol production wastewater is known to be toxic, and is not easily biodegradable. It also consists of a variety of coloured components adding to the complex composition of this wastewater. Disposal of this wastewater into water courses is not recommended and yet is performed all over the world. Investigation of this wastewater found that there was a high concentration of sulphate which, in the presence of sulphate-reducing prokaryotes can cause sulphide corrosion of cement. The concentration of sulphate in the wastewater was approximately 2770 mg/L. It was also found that the wastewater pH was very low and discharge of the wastewater into the wastewater treatment works caused a negative impact on the overall quality of the final wastewater discharged to sea. It was found using FISH techniques that there were no sulphate-reducing prokaryotes present in the wastewaters but that a sulphate-reducing population existed on the sewer wall. An anaerobic contact process was designed to treat this wastewater targeting sulphate reduction to sulphide, to be converted into elemental sulphur and to increase the wastewater pH. The process did not achieve this aim and only approximately 20-30 % reduction in sulphate from the wastewater was achieved with little to no change in the pH. A 95 % reduction in sulphate concentration was needed in order to reach acceptable discharge limits. Sulphate reduction could not be carried out, even under ideal laboratory conditions. It was found that the barrier causing the digester failure was the high concentration of phenols present in the wastewater (3.3 g/L) together with the production of high concentrations of volatile fatty acids (on average 13 g acetic/L). These two components are known to cause digester failure, especially phenols, and phenols are usually only degraded by fungal species. It was concluded that the wastewater itself was not amenable to this method of biological treatment.
- Full Text:
- Date Issued: 2005
Ligand isotope vibrational spectroscopic and DFT studies of Pt(II) and Cu(I) complexes
- Authors: Medina, Gerardo Juan
- Date: 2005
- Subjects: Ligands Spectrum analysis Vibrational spectra Infrared spectroscopy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4324 , http://hdl.handle.net/10962/d1004982
- Description: Ligand-isotope labelling studies were performed on Zeise’s salt derivatives with pyridine N-oxide and quinoline N-oxide, their perdeuterated and O-18 isotopomers, C₂D₄ and ¹³CO, and the results of the vibrational analyses are reported. The isotopomers are modelled utilizing DFT calculations at the B3LYP level with the 6-31 G** basis set, and a pseudopotential level for the Pt atom. The calculated and observed structure and vibrational spectra correlate well. The crystal structures of [Pt(C₂2H₄)(pyO)Cl₂] and [Pt(CO)(quinO)Br₂] are reported. The frequency for the νPt-O vibration, ambiguously assigned in the literature, is here assigned unequivocally at 400 cm⁻¹. Previously observed, but inadequately described phenomena are addressed: the νN-O vibration in substituted quinoline N-oxides has been assigned previously at significantly different frequencies, depending on the nature of the substituent. This suggests that there is no specific mid-ir band associated with a high N-O character. A suitable explanation is presented for this phenomenon, showing that in low symmetry systems (eg. quinO) the N-O stretch is dispersed among several modes, whereas in high symmetry systems (eg. pyO) only a few limited modes have a high N-O character. A theoretical study of Cu(I) carbonyl compounds with macrocyclic ligands is presented. Local and global HSAB parameters applied to the donor and Cu atoms are used to explain the observed reactivities and the available spectroscopic data. Extended to [Cu(CO){H₂N(CH₂)[subscript n]NH(CH₂)[subscript m] NH₂}] BPh₄ (where n = 2, m = 2, 3 and n =3, m = 3, 4) and their -d₅ and ¹³CO isotopomers, subtle differences obtained experimentally for the CO stretching frequency in this series have been reproduced in the DFT calculations at the B3LYP level, using the 6-31 G* and 6-31 G** basis sets. Several properties (ligand pK[subscript a] values, νCO frequencies, etc.) correlate with some HSAB descriptors. Vibrational analyses are presented of Cu(I) carbonyl Schiff-base derivatives of N-Benzylidene-N’-[2-(benzyilidene-amino)-ethyl]-ethane-1,2-diamine, {2,2N3(C₆H₄R)₂}, and their -d₅ and ¹³CO isotopomers. The crystal structure of [Cu(CO){2,2N3(C₆H₅)₂}]BPh₄ is reported. From geometry optimizations and the HSAB descriptors, spectroscopic trends ([n]Cu-N and [nu]CO) are related to calculated global hardness and the Hammett substituent parameters, and are discussed in terms of σ-donation and π-backbonding of Cu- CO.
- Full Text:
- Date Issued: 2005
- Authors: Medina, Gerardo Juan
- Date: 2005
- Subjects: Ligands Spectrum analysis Vibrational spectra Infrared spectroscopy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4324 , http://hdl.handle.net/10962/d1004982
- Description: Ligand-isotope labelling studies were performed on Zeise’s salt derivatives with pyridine N-oxide and quinoline N-oxide, their perdeuterated and O-18 isotopomers, C₂D₄ and ¹³CO, and the results of the vibrational analyses are reported. The isotopomers are modelled utilizing DFT calculations at the B3LYP level with the 6-31 G** basis set, and a pseudopotential level for the Pt atom. The calculated and observed structure and vibrational spectra correlate well. The crystal structures of [Pt(C₂2H₄)(pyO)Cl₂] and [Pt(CO)(quinO)Br₂] are reported. The frequency for the νPt-O vibration, ambiguously assigned in the literature, is here assigned unequivocally at 400 cm⁻¹. Previously observed, but inadequately described phenomena are addressed: the νN-O vibration in substituted quinoline N-oxides has been assigned previously at significantly different frequencies, depending on the nature of the substituent. This suggests that there is no specific mid-ir band associated with a high N-O character. A suitable explanation is presented for this phenomenon, showing that in low symmetry systems (eg. quinO) the N-O stretch is dispersed among several modes, whereas in high symmetry systems (eg. pyO) only a few limited modes have a high N-O character. A theoretical study of Cu(I) carbonyl compounds with macrocyclic ligands is presented. Local and global HSAB parameters applied to the donor and Cu atoms are used to explain the observed reactivities and the available spectroscopic data. Extended to [Cu(CO){H₂N(CH₂)[subscript n]NH(CH₂)[subscript m] NH₂}] BPh₄ (where n = 2, m = 2, 3 and n =3, m = 3, 4) and their -d₅ and ¹³CO isotopomers, subtle differences obtained experimentally for the CO stretching frequency in this series have been reproduced in the DFT calculations at the B3LYP level, using the 6-31 G* and 6-31 G** basis sets. Several properties (ligand pK[subscript a] values, νCO frequencies, etc.) correlate with some HSAB descriptors. Vibrational analyses are presented of Cu(I) carbonyl Schiff-base derivatives of N-Benzylidene-N’-[2-(benzyilidene-amino)-ethyl]-ethane-1,2-diamine, {2,2N3(C₆H₄R)₂}, and their -d₅ and ¹³CO isotopomers. The crystal structure of [Cu(CO){2,2N3(C₆H₅)₂}]BPh₄ is reported. From geometry optimizations and the HSAB descriptors, spectroscopic trends ([n]Cu-N and [nu]CO) are related to calculated global hardness and the Hammett substituent parameters, and are discussed in terms of σ-donation and π-backbonding of Cu- CO.
- Full Text:
- Date Issued: 2005
The therapist as a "bad object": the use of countertransference enactment to facilitate communication in therapy
- Authors: Webster, Penny
- Date: 2005
- Subjects: Countertransference (Psychology) Countertransference (Psychology) -- Therapeutic use Communication -- Psychological aspects Psychotherapist and patient Psychoanalysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3083 , http://hdl.handle.net/10962/d1002592
- Description: Psychoanalysis as it exists today is not constituted by a single theoretical framework describing pathology and indicating a specific set of interventions. Since Freud originally conceptualised psychoanalytic understanding of pathology and psychoanalysis as a mode of intervention, there have been many revisions and reformulations of his theory. This thesis has attempted to integrate some psychoanalytic ideas regarding personality formation, psychopathology and psychotherapeutic intervention (Fairbairn, 1952; Ogden, 1992, 1994), with interpersonal (strategic / structural) ideas regarding intervention (Minuchin, 1974; Sullivan, 1940, 1953, 1964). In order to do so, the thesis used the relational psychoanalytic perspective, as depicted by Aron (1996) and Mitchell and Aron (1999), as an overarching conceptual framework. The focus from these points of view is the patient's internalized relationship patterns and the therapist's participation in their repetition. It is held that internalized relationship patterns are not only based on, but can be changed by, lived experience. From this perspective, the goal of therapy is to enhance the patient's capacity to reflect and think about experience, and therefore, to communicate about it. This means a change in the patient's predominant mode of communication. Ogden's (1994) modes of communication were described. The thesis suggested that Ogden's modes of communication can be stretched or translated into the types of communication outlined by Langs (1978). This thesis aimed to explore the deliberate use of countertransference responses to facilitate communication in the beginning stages of therapy with patients functioning predominantly in the paranoid-schizoid mode (Ogden, 1992). Patients who operate in this mode are often unable to tolerate interpretation and therefore traditional approaches to intervention are not effective. A "strategic / structural relational psychoanalytic" approach to treatment was proposed. It was suggested that therapists utilize joining and accommodation techniques as described by Minuchin (1974) and alter their style of interaction to match that of the various object relational constellations that they have managed to identify within the patient via their countertransference responses. It was hypothesized that patients need their therapists to be similar to their original objects in order to feel safe in the therapeutic environment and that this may facilitate communication in the beginning stages of therapy. The research utilized a qualitative research approach. Qualitative research methods attempt to use data gathered phenomenologically, always acknowledging the researcher's biases when gathering the data. The data gathered is then interpreted according to various theories or hermeneutic lenses. The hypothesis mentioned above has been investigated by analyzing three cases in terms of the research questions based on Langs' (1978) classification of communication. The thesis described the difficulties inherent in collecting clinical data from psychologists working from within a psychoanalytic framework. Eventually three sets of therapy details and verbatim therapy transcripts were obtained, provided in the thesis and analyzed in terms of the research questions. However evidence for the success of the hypothesized alternate approach was not found in this research study. It was suggested that other possible methods might be useful to investigate the hypothesized approach further.
- Full Text:
- Date Issued: 2005
- Authors: Webster, Penny
- Date: 2005
- Subjects: Countertransference (Psychology) Countertransference (Psychology) -- Therapeutic use Communication -- Psychological aspects Psychotherapist and patient Psychoanalysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3083 , http://hdl.handle.net/10962/d1002592
- Description: Psychoanalysis as it exists today is not constituted by a single theoretical framework describing pathology and indicating a specific set of interventions. Since Freud originally conceptualised psychoanalytic understanding of pathology and psychoanalysis as a mode of intervention, there have been many revisions and reformulations of his theory. This thesis has attempted to integrate some psychoanalytic ideas regarding personality formation, psychopathology and psychotherapeutic intervention (Fairbairn, 1952; Ogden, 1992, 1994), with interpersonal (strategic / structural) ideas regarding intervention (Minuchin, 1974; Sullivan, 1940, 1953, 1964). In order to do so, the thesis used the relational psychoanalytic perspective, as depicted by Aron (1996) and Mitchell and Aron (1999), as an overarching conceptual framework. The focus from these points of view is the patient's internalized relationship patterns and the therapist's participation in their repetition. It is held that internalized relationship patterns are not only based on, but can be changed by, lived experience. From this perspective, the goal of therapy is to enhance the patient's capacity to reflect and think about experience, and therefore, to communicate about it. This means a change in the patient's predominant mode of communication. Ogden's (1994) modes of communication were described. The thesis suggested that Ogden's modes of communication can be stretched or translated into the types of communication outlined by Langs (1978). This thesis aimed to explore the deliberate use of countertransference responses to facilitate communication in the beginning stages of therapy with patients functioning predominantly in the paranoid-schizoid mode (Ogden, 1992). Patients who operate in this mode are often unable to tolerate interpretation and therefore traditional approaches to intervention are not effective. A "strategic / structural relational psychoanalytic" approach to treatment was proposed. It was suggested that therapists utilize joining and accommodation techniques as described by Minuchin (1974) and alter their style of interaction to match that of the various object relational constellations that they have managed to identify within the patient via their countertransference responses. It was hypothesized that patients need their therapists to be similar to their original objects in order to feel safe in the therapeutic environment and that this may facilitate communication in the beginning stages of therapy. The research utilized a qualitative research approach. Qualitative research methods attempt to use data gathered phenomenologically, always acknowledging the researcher's biases when gathering the data. The data gathered is then interpreted according to various theories or hermeneutic lenses. The hypothesis mentioned above has been investigated by analyzing three cases in terms of the research questions based on Langs' (1978) classification of communication. The thesis described the difficulties inherent in collecting clinical data from psychologists working from within a psychoanalytic framework. Eventually three sets of therapy details and verbatim therapy transcripts were obtained, provided in the thesis and analyzed in terms of the research questions. However evidence for the success of the hypothesized alternate approach was not found in this research study. It was suggested that other possible methods might be useful to investigate the hypothesized approach further.
- Full Text:
- Date Issued: 2005
An exploration of understandings and expectations around differentiation in mathematics, science and technology education
- Authors: Cherub, Fauzia
- Date: 2005
- Subjects: Education -- South Africa Educational evaluation -- South Africa Comparative education Mathematics -- Study and teaching -- South Africa Science -- Study and teaching -- South Africa Technology -- Study and teaching -- South Africa Education and state -- South Africa Differentiation (Sociology) Competency-based education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1947 , http://hdl.handle.net/10962/d1008179
- Description: The exploratory study presented in this thesis is a case study, interpretive in nature and located in the qualitative paradigm. The conceptual focus is on differentiation, recognizing that learners vary from one another and so will need educators to consider a wide range of factors to enable learners to learn. The objectives of the study are: • To identify what Whole School Evaluation (WSE) supervisors understand by the term differentiation (conceptual) • To identify how WSE supervisors expect differentiation to be achieved by educators (conceptual). [n order to contextualise this research, a further objective was considered necessary: • To identify the roles of WSE supervisors (contextual) This was set in the context of mathematics, science and technology education. The study was carried out with a group of ten WSE supervisors who were involved in evaluating Mathematics, Science and or Technology education in the GET (General Education and Training) Band. Analysis of questionnaires and documents led to the identification of supervisory roles, while analysis of semi-structured interviews revealed a range of dimensions related to differentiation understandings and expectations. These dimensions have been developed into a typology which is then drawn upon in the development of a new conceptual model of differentiation, particularly relevant to the South African context. Findings presented in the study represent an attempt to understand and make recommendations related to policy, practice, research, curriculum and learning support material (LSM) development, training and evaluation. Textual layering in the form of reflective footnotes and issue boxes. plus specific reflective sections in the main text e.g. limitations and assumptions, help the text to achieve this goal. While the study was focused on the context of mathematics, science and technology education, it became apparent that the findings could be applied across all the learning areas.
- Full Text:
- Date Issued: 2005
- Authors: Cherub, Fauzia
- Date: 2005
- Subjects: Education -- South Africa Educational evaluation -- South Africa Comparative education Mathematics -- Study and teaching -- South Africa Science -- Study and teaching -- South Africa Technology -- Study and teaching -- South Africa Education and state -- South Africa Differentiation (Sociology) Competency-based education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1947 , http://hdl.handle.net/10962/d1008179
- Description: The exploratory study presented in this thesis is a case study, interpretive in nature and located in the qualitative paradigm. The conceptual focus is on differentiation, recognizing that learners vary from one another and so will need educators to consider a wide range of factors to enable learners to learn. The objectives of the study are: • To identify what Whole School Evaluation (WSE) supervisors understand by the term differentiation (conceptual) • To identify how WSE supervisors expect differentiation to be achieved by educators (conceptual). [n order to contextualise this research, a further objective was considered necessary: • To identify the roles of WSE supervisors (contextual) This was set in the context of mathematics, science and technology education. The study was carried out with a group of ten WSE supervisors who were involved in evaluating Mathematics, Science and or Technology education in the GET (General Education and Training) Band. Analysis of questionnaires and documents led to the identification of supervisory roles, while analysis of semi-structured interviews revealed a range of dimensions related to differentiation understandings and expectations. These dimensions have been developed into a typology which is then drawn upon in the development of a new conceptual model of differentiation, particularly relevant to the South African context. Findings presented in the study represent an attempt to understand and make recommendations related to policy, practice, research, curriculum and learning support material (LSM) development, training and evaluation. Textual layering in the form of reflective footnotes and issue boxes. plus specific reflective sections in the main text e.g. limitations and assumptions, help the text to achieve this goal. While the study was focused on the context of mathematics, science and technology education, it became apparent that the findings could be applied across all the learning areas.
- Full Text:
- Date Issued: 2005
Formulation and assessment of verapamil sustained release tablets
- Khamanga, Sandile Maswazi Malungelo
- Authors: Khamanga, Sandile Maswazi Malungelo
- Date: 2005
- Subjects: Verapamil , Tablets (Medicine) , Drugs -- Administration , Cardiovascular agents , Calcium -- Antagonists , Drugs -- Controlled release
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3869 , http://hdl.handle.net/10962/d1018236
- Description: The oral route of drug administration is most extensively used due to the obvious ease of administration. Verapamil hydrochloride is a WHO listed phenylalkylarnine, L-type calcium channel antagonist that is mainly indicated for cardiovascular disorders such as angina pectoris, supraventricular tachycardia and hypertension. Due to its relatively short half-life of approximately 4.0 hours, the formulation of a sustained-release dosage form is useful to improve patient compliance and to achieve predictable and optimized therapeutic plasma concentrations. Direct compression and wet granulation were initially used as methods for tablet manufacture. The direct compression method of manufacture produced tablets that exhibited formulation and manufacturing difficulties. Mini-tablets containing veraparnil hydrochloride were then prepared by wet granulation using Surelease® E-7-19010.and Eudragit® NE 30D as the granulating agents after which the granules were incorporated with an hydrophilic matrix material, Carbopol® 974P NF. Granule and powder blends were evaluated using the angle of repose, loose and tapped bulk density, Can's compressibility index, Hausner's ratio and drug content. Granules with good flow properties and satisfactory compressibility were used for further studies. Tablets were subjected to thickness, diameter and weight variation tests, crushing strength, tensile strength, friability and content uniformity studies. Tablets that showed acceptable pharmaco-technical properties were selected for further analysis. Drug content uniformity and dissolution release rates were determined using a validated isocratic HPLC method. Initially, USP apparatus 1 and 3 dissolution apparatus were used to determine in-vitro drug release rates from the formulations over a 22-hour period. USP apparatus 3 was finally selected as it offers the advantages of mimicking, in part, the changes in the physicochemical environment experienced by products in the gastro-intestinal tract. Differences in release rates between the test formulations and a commercially available product, Isoptin® SR were observed at different pH's using USP apparatus 1. The release of veraparnil hydrochloride from matrix tablets was pH dependent and was markedly reduced at higher pH values. This may be due, in part, to the poor solubility of veraparnil hydrochloride at these pH values and also the possible interaction of verapamil hydrochloride with anionic polymers used in these formulations. Swelling and erosion behaviour of the tablets were evaluated and differences in behaviour were observed which may be attributed to the physico-chemical characteristics of the polymers used in this study. In-vitro dissolution profiles were characterized by the difference (j1) and similarity factor (j2) and also by a new similarity factor, Sct. In addition, the mechanism of drug release from these dosage forms was mainly evaluated using the Korsmeyer-Peppas model and the kinetics of drug release assessed using other models, including Zero order, First order, Higuchi, HixsonCrowell, Weibull and the Baker-Lonsdale model. Dissolution kinetics were best described by application of the Weibull model, and the Korsmeyer-Peppas model. The release exponent, n, confirmed that drug release from these dosage forms was due to the mixed effects of diffusion and swelling and therefore, anomalous release kinetics are predominant. In conclusion, two test batches were found to be comparable to the reference product Isoptin® SR with respect to their in-vitro release profiles.
- Full Text:
- Date Issued: 2005
- Authors: Khamanga, Sandile Maswazi Malungelo
- Date: 2005
- Subjects: Verapamil , Tablets (Medicine) , Drugs -- Administration , Cardiovascular agents , Calcium -- Antagonists , Drugs -- Controlled release
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3869 , http://hdl.handle.net/10962/d1018236
- Description: The oral route of drug administration is most extensively used due to the obvious ease of administration. Verapamil hydrochloride is a WHO listed phenylalkylarnine, L-type calcium channel antagonist that is mainly indicated for cardiovascular disorders such as angina pectoris, supraventricular tachycardia and hypertension. Due to its relatively short half-life of approximately 4.0 hours, the formulation of a sustained-release dosage form is useful to improve patient compliance and to achieve predictable and optimized therapeutic plasma concentrations. Direct compression and wet granulation were initially used as methods for tablet manufacture. The direct compression method of manufacture produced tablets that exhibited formulation and manufacturing difficulties. Mini-tablets containing veraparnil hydrochloride were then prepared by wet granulation using Surelease® E-7-19010.and Eudragit® NE 30D as the granulating agents after which the granules were incorporated with an hydrophilic matrix material, Carbopol® 974P NF. Granule and powder blends were evaluated using the angle of repose, loose and tapped bulk density, Can's compressibility index, Hausner's ratio and drug content. Granules with good flow properties and satisfactory compressibility were used for further studies. Tablets were subjected to thickness, diameter and weight variation tests, crushing strength, tensile strength, friability and content uniformity studies. Tablets that showed acceptable pharmaco-technical properties were selected for further analysis. Drug content uniformity and dissolution release rates were determined using a validated isocratic HPLC method. Initially, USP apparatus 1 and 3 dissolution apparatus were used to determine in-vitro drug release rates from the formulations over a 22-hour period. USP apparatus 3 was finally selected as it offers the advantages of mimicking, in part, the changes in the physicochemical environment experienced by products in the gastro-intestinal tract. Differences in release rates between the test formulations and a commercially available product, Isoptin® SR were observed at different pH's using USP apparatus 1. The release of veraparnil hydrochloride from matrix tablets was pH dependent and was markedly reduced at higher pH values. This may be due, in part, to the poor solubility of veraparnil hydrochloride at these pH values and also the possible interaction of verapamil hydrochloride with anionic polymers used in these formulations. Swelling and erosion behaviour of the tablets were evaluated and differences in behaviour were observed which may be attributed to the physico-chemical characteristics of the polymers used in this study. In-vitro dissolution profiles were characterized by the difference (j1) and similarity factor (j2) and also by a new similarity factor, Sct. In addition, the mechanism of drug release from these dosage forms was mainly evaluated using the Korsmeyer-Peppas model and the kinetics of drug release assessed using other models, including Zero order, First order, Higuchi, HixsonCrowell, Weibull and the Baker-Lonsdale model. Dissolution kinetics were best described by application of the Weibull model, and the Korsmeyer-Peppas model. The release exponent, n, confirmed that drug release from these dosage forms was due to the mixed effects of diffusion and swelling and therefore, anomalous release kinetics are predominant. In conclusion, two test batches were found to be comparable to the reference product Isoptin® SR with respect to their in-vitro release profiles.
- Full Text:
- Date Issued: 2005
A history of the direct taxation of the African people of Kenya, 1895-1973
- Authors: Tarus, Isaac Kipsang
- Date: 2005
- Subjects: Mau Mau -- History Taxation -- Kenya Tax collection -- Kenya Fiscal policy -- Kenya Kenya -- Economic policy Kenya -- History -- 1895-1963
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2561 , http://hdl.handle.net/10962/d1002414
- Description: This study examines the origin, the manifestation and impact of the direct taxation of Africans in Kenya. While the state had several reasons for imposing taxation on Africans, the basic factor weighed on the need for a definitive source of revenue. For most of the colonial period, this aggregated to about 37½ percent of the total revenues. The thesis shows how taxes were collected from Africans, how this led to participation in the cash economy and how they continually resisted and evaded such taxation. Tax collection was synonymous with colonialism and this was manifested through the central role of chiefs, who used taxes and force to coerce Africans into migrant wage labour. Through taxation policies, legislation and African resourcefulness, migrant wage labour served the needs of a colonial capitalist settler economy. In this way, the colonial state revealed its capacity for dominance, power and exploitation. Evidence has been adduced to show that African taxation was an important factor in Kenya’s administrative, political and economic development. The policy of African taxation, land loss and poor working conditions are remembered as having interfered with African mechanisms for accumulating wealth. One of the main objections of the payment of taxes was the manner of its collection. Those unable to pay were imprisoned or detained while many took to instant flight at the sight of the tax collector. The thesis shows that in spite of all these harsh tax collection methods, peasants remained largely resilient and industrious. The Mau Mau movement was the culmination of various peasant grievances in which the colonial state used steep taxation as a counter-insurgency measure. Kenya’s independence in 1963, however, never altered the predatory nature of the state. Subtle, opportunistic and overt ways continued to be used to extract taxes from the peasants and the working class. It was not until 1973 that the much-hated colonial poll tax that had been renamed as graduated poll tax was abolished and replaced by indirect taxation. Finally, taxation like other colonial legacies has endured and has become one of the most important sources of revenue for the government to manage its fiscal policies.
- Full Text:
- Date Issued: 2005
- Authors: Tarus, Isaac Kipsang
- Date: 2005
- Subjects: Mau Mau -- History Taxation -- Kenya Tax collection -- Kenya Fiscal policy -- Kenya Kenya -- Economic policy Kenya -- History -- 1895-1963
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2561 , http://hdl.handle.net/10962/d1002414
- Description: This study examines the origin, the manifestation and impact of the direct taxation of Africans in Kenya. While the state had several reasons for imposing taxation on Africans, the basic factor weighed on the need for a definitive source of revenue. For most of the colonial period, this aggregated to about 37½ percent of the total revenues. The thesis shows how taxes were collected from Africans, how this led to participation in the cash economy and how they continually resisted and evaded such taxation. Tax collection was synonymous with colonialism and this was manifested through the central role of chiefs, who used taxes and force to coerce Africans into migrant wage labour. Through taxation policies, legislation and African resourcefulness, migrant wage labour served the needs of a colonial capitalist settler economy. In this way, the colonial state revealed its capacity for dominance, power and exploitation. Evidence has been adduced to show that African taxation was an important factor in Kenya’s administrative, political and economic development. The policy of African taxation, land loss and poor working conditions are remembered as having interfered with African mechanisms for accumulating wealth. One of the main objections of the payment of taxes was the manner of its collection. Those unable to pay were imprisoned or detained while many took to instant flight at the sight of the tax collector. The thesis shows that in spite of all these harsh tax collection methods, peasants remained largely resilient and industrious. The Mau Mau movement was the culmination of various peasant grievances in which the colonial state used steep taxation as a counter-insurgency measure. Kenya’s independence in 1963, however, never altered the predatory nature of the state. Subtle, opportunistic and overt ways continued to be used to extract taxes from the peasants and the working class. It was not until 1973 that the much-hated colonial poll tax that had been renamed as graduated poll tax was abolished and replaced by indirect taxation. Finally, taxation like other colonial legacies has endured and has become one of the most important sources of revenue for the government to manage its fiscal policies.
- Full Text:
- Date Issued: 2005
Investigating call control using MGCP in conjuction with SIP and H.323
- Authors: Jacobs, Ashley
- Date: 2005 , 2005-03-14
- Subjects: Communication -- Technological innovations , Digital telephone systems , Computer networks , Computer network protocols , Internet telephony
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4631 , http://hdl.handle.net/10962/d1006516 , Communication -- Technological innovations , Digital telephone systems , Computer networks , Computer network protocols , Internet telephony
- Description: Telephony used to mean using a telephone to call another telephone on the Public Switched Telephone Network (PSTN), and data networks were used purely to allow computers to communicate. However, with the advent of the Internet, telephony services have been extended to run on data networks. Telephone calls within the IP network are known as Voice over IP. These calls are carried by a number of protocols, with the most popular ones currently being Session Initiation Protocol (SIP) and H.323. Calls can be made from the IP network to the PSTN and vice versa through the use of a gateway. The gateway translates the packets from the IP network to circuits on the PSTN and vice versa to facilitate calls between the two networks. Gateways have evolved and are now split into two entities using the master/slave architecture. The master is an intelligent Media Gateway Controller (MGC) that handles the call control and signalling. The slave is a "dumb" Media Gateway (MG) that handles the translation of the media. The current gateway control protocols in use are Megaco/H.248, MGCP and Skinny. These protocols have proved themselves on the edge of the network. Furthermore, since they communicate with the call signalling VoIP protocols as well as the PSTN, they have to be the lingua franca between the two networks. Within the VoIP network, the numbers of call signalling protocols make it difficult to communicate with each other and to create services. This research investigates the use of Gateway Control Protocols as the lowest common denominator between the call signalling protocols SIP and H.323. More specifically, it uses MGCP to investigate service creation. It also considers the use of MGCP as a protocol translator between SIP and H.323. A service was created using MGCP to allow H.323 endpoints to send Short Message Service (SMS) messages. This service was then extended with minimal effort to SIP endpoints. This service investigated MGCP’s ability to handle call control from the H.323 and SIP endpoints. An MGC was then successfully used to perform as a protocol translator between SIP and H.323.
- Full Text:
- Date Issued: 2005
- Authors: Jacobs, Ashley
- Date: 2005 , 2005-03-14
- Subjects: Communication -- Technological innovations , Digital telephone systems , Computer networks , Computer network protocols , Internet telephony
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4631 , http://hdl.handle.net/10962/d1006516 , Communication -- Technological innovations , Digital telephone systems , Computer networks , Computer network protocols , Internet telephony
- Description: Telephony used to mean using a telephone to call another telephone on the Public Switched Telephone Network (PSTN), and data networks were used purely to allow computers to communicate. However, with the advent of the Internet, telephony services have been extended to run on data networks. Telephone calls within the IP network are known as Voice over IP. These calls are carried by a number of protocols, with the most popular ones currently being Session Initiation Protocol (SIP) and H.323. Calls can be made from the IP network to the PSTN and vice versa through the use of a gateway. The gateway translates the packets from the IP network to circuits on the PSTN and vice versa to facilitate calls between the two networks. Gateways have evolved and are now split into two entities using the master/slave architecture. The master is an intelligent Media Gateway Controller (MGC) that handles the call control and signalling. The slave is a "dumb" Media Gateway (MG) that handles the translation of the media. The current gateway control protocols in use are Megaco/H.248, MGCP and Skinny. These protocols have proved themselves on the edge of the network. Furthermore, since they communicate with the call signalling VoIP protocols as well as the PSTN, they have to be the lingua franca between the two networks. Within the VoIP network, the numbers of call signalling protocols make it difficult to communicate with each other and to create services. This research investigates the use of Gateway Control Protocols as the lowest common denominator between the call signalling protocols SIP and H.323. More specifically, it uses MGCP to investigate service creation. It also considers the use of MGCP as a protocol translator between SIP and H.323. A service was created using MGCP to allow H.323 endpoints to send Short Message Service (SMS) messages. This service was then extended with minimal effort to SIP endpoints. This service investigated MGCP’s ability to handle call control from the H.323 and SIP endpoints. An MGC was then successfully used to perform as a protocol translator between SIP and H.323.
- Full Text:
- Date Issued: 2005
Strategic leadership within the Duke of Edinburgh's International Award Association between 1988 and 2004
- Authors: Andrew, Craig Bruce
- Date: 2005
- Subjects: Duke of Edinburgh's Award (Organization) Duke of Edinburgh's Award -- History Nonprofit organizations -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:764 , http://hdl.handle.net/10962/d1003885
- Description: Providing strategic leadership for global Not-for-Profit organisations poses great challenges to the leadership structures of these voluntary organisations. This study looks at the phenomenon of strategic leadership in the Duke of Edinburgh’s (DOE) International Award Association (IAA) as a global Not-for-Profit Organisation (NPO). The main aim of the research was an in-depth examination of the processes involved in leadership at the top level in a global NPO. Eight strategic leaders from the top management team were interviewed. Further information was generated from a study of the Annual Reports spanning the 15 year period (1988/9 – 2003/4), and key strategic documents were used as supporting material. The research was conducted in a phenomenological paradigm, using the case study research method. Care was taken to minimize possible researcher bias and interpretations, as the researcher has been associated with this organisation for the past 18 years. It was found that the Royal Family play extremely valuable and multifaceted roles in the organisation. The triumvirate of The Royals; The Secretary General’s; and The Trustees; works well as individual ‘great groups’ yet when necessary, they form a collective collaborative grouping to effect strategic leadership for the IAA. The two main themes to emerge from the findings were the nature of the DOE as a global NPO and the role of strategic leadership in the DOE Award. The DOE Award has demonstrated that it has many unique strategic leadership features and is using these features to become more business-like in the application of its new strategic vision. The individual ‘great groups’ offer sound leadership throughout the process of overseeing and running the business of the DOE Award yet, when necessary and appropriate, these great groups appear to work collectively, perhaps in an unstructured manner, as the triumvirate of power. Their collective collaborative leadership is a unique feature of the DOE Award. The highly interactive role of the Royal Family is unique and sets the DOE Award apart from other similar youth organisations globally. The nature of the loose association of National Award Authorities all subscribing to the rules and conditions of association is also a very unique feature of this NPO. The DOE Award is not a movement organisation but is guided by its service ethic. The DOE Award is a service organisation in which the strategic leadership plays a crucial role yet the constitutional power resides with the International Award Association membership. This IAA membership meets every three years at the World Forum Triennium to approve all new policy and procedures.
- Full Text:
- Date Issued: 2005
- Authors: Andrew, Craig Bruce
- Date: 2005
- Subjects: Duke of Edinburgh's Award (Organization) Duke of Edinburgh's Award -- History Nonprofit organizations -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:764 , http://hdl.handle.net/10962/d1003885
- Description: Providing strategic leadership for global Not-for-Profit organisations poses great challenges to the leadership structures of these voluntary organisations. This study looks at the phenomenon of strategic leadership in the Duke of Edinburgh’s (DOE) International Award Association (IAA) as a global Not-for-Profit Organisation (NPO). The main aim of the research was an in-depth examination of the processes involved in leadership at the top level in a global NPO. Eight strategic leaders from the top management team were interviewed. Further information was generated from a study of the Annual Reports spanning the 15 year period (1988/9 – 2003/4), and key strategic documents were used as supporting material. The research was conducted in a phenomenological paradigm, using the case study research method. Care was taken to minimize possible researcher bias and interpretations, as the researcher has been associated with this organisation for the past 18 years. It was found that the Royal Family play extremely valuable and multifaceted roles in the organisation. The triumvirate of The Royals; The Secretary General’s; and The Trustees; works well as individual ‘great groups’ yet when necessary, they form a collective collaborative grouping to effect strategic leadership for the IAA. The two main themes to emerge from the findings were the nature of the DOE as a global NPO and the role of strategic leadership in the DOE Award. The DOE Award has demonstrated that it has many unique strategic leadership features and is using these features to become more business-like in the application of its new strategic vision. The individual ‘great groups’ offer sound leadership throughout the process of overseeing and running the business of the DOE Award yet, when necessary and appropriate, these great groups appear to work collectively, perhaps in an unstructured manner, as the triumvirate of power. Their collective collaborative leadership is a unique feature of the DOE Award. The highly interactive role of the Royal Family is unique and sets the DOE Award apart from other similar youth organisations globally. The nature of the loose association of National Award Authorities all subscribing to the rules and conditions of association is also a very unique feature of this NPO. The DOE Award is not a movement organisation but is guided by its service ethic. The DOE Award is a service organisation in which the strategic leadership plays a crucial role yet the constitutional power resides with the International Award Association membership. This IAA membership meets every three years at the World Forum Triennium to approve all new policy and procedures.
- Full Text:
- Date Issued: 2005
An investigation into the antidepressant activity of hypericum perforatum
- Authors: Stephens, Linda Lee
- Date: 2005
- Subjects: Hypericum perforatum -- Physiological effect Hypericum perforatum -- Therapeutic use Antidepressants
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3793 , http://hdl.handle.net/10962/d1003271
- Description: Hypericum perforatum is a herbal medicine that has been used for centuries for the treatment of depression. Many studies have been conducted in the Northern hemisphere on the efficacy of the HP extracts produced there. These studies include clinical trials and pharmacological investigations using a standardised HP extract or a fraction of the HP extract containing certain compounds, such as hypericin, pseudohypericin, hyperforin and several of the flavonoids thought to be responsible for the antidepressant activity. The mechanism of action of HP and its constituents is still not completely clear and it is speculated that the antidepressant activity is the result of several of the compounds acting synergistically. HP is indigenous to and also cultivated in the Western Cape of South Africa. Extracts from these plants are sold in the local health shops and there are no previous studies evaluating the efficacy of these products. The aim of this thesis is to investigate the antidepressant activity of one of these products and two of its constituents, quercetin and caffeic acid, to gain further insight into their mode of antidepressant action and to compare these results with similar studies which used a standardised extract produced in the northern hemisphere. The first study investigated the effect of HP, quercetin and caffeic acid on pineal metabolism. Changes in the synthesis of melatonin produced by the pineal gland have been implicated in depression. The results showed an increase in the level of melatonin produced in the animals treated with quercetin, which suggests that this compound may mediate antidepressant activity through such a mechanism. There are no previous reports on the in vivo effects of HP or any of its constituents on pineal metabolism. The second study investigated the effect of HP, quercetin and caffeic acid on the activity of the liver enzyme, tryptophan-2,3-dioxygenase (TDO). Inhibition of this enzyme has been shown to increase plasma levels of tryptophan, a precursor of serotonin and thereby result in increased serotonin levels in the brain. Low levels of serotonin in the brain have been implicated in depression. This study revealed significant inhibition of TDO by caffeic acid and this suggests that this constituent of HP could be contributing to its antidepressant activity through such a mechanism. There are no previous reports investigating the in vivo effect of HP or any of its constituents on TDO activity. Modulation of the levels of indoleamines, serotonin (5-HT) and dopamine (DA) as well as the metabolites, 3,4 dihydroxyphenyl acetic acid (DOPAC), 5-hydroxyindole acetic acid (5-HIAA) and homovallinic acid (HVA) in the brain have been implicated in the neuropharmacology of depression. Different studies using enzyme-linked immunosorbant assay (ELISA), high performance liquid chromatography with electrochemical detection (HPLC-ECD) and liquid chromatography-mass spectrometry (LC-MS) were used to determine changes in the levels of these indoleamines brought about after treatment with HP caffeic acid and quercetin. The results of the ELISA study showed significant increases in 5-HT levels in the brains of the animals treated with caffeic acid and quercetin. The results of the HPLC-ECD studies also revealed significant increases in 5-HT levels and a decrease in the turnover of 5-HT in the animals treated with quercetin. A significant increase in DA levels in the animals treated with quercetin was shown in both the HPLC-ECD and LC-MS studies. There was also an increase in DA turnover in the animals treated with HP shown in the HPLC-ECD and LC-MS studies. These results suggest that HP and its constituents, quercetin and caffeic acid mediate their antidepressant effects through serotonergic and dopaminergic neurotransmission. Adaptive changes in the density of b-adrenergic (b-AR), 5-HT2 and N-methyl-D-aspartate (NMDA) receptors have been implicated in depression. Several studies, investigating the effect of treatment with HP and quercetin on these different receptor densities, were undertaken using radioactive binding assays. Treatment with HP resulted in significant down regulation of b-AR and NMDA receptor densities and up-regulation of 5HT2 receptors. The effects on the b-AR and 5-HT2 receptors are similar to the results reported using HP in the Northern hemisphere, but the effect on the NMDA receptors is novel providing insight into the mode of action of HP. Apoptosis of neuronal cells has been implicated in neuro-degenerative and depressive disorders. Detection of apoptosis, using fluorescent microscopy observed through the labelling of DNA strand breaks, showed a decrease in the amount of apoptosis in the animals treated with HP and quercetin. This adds further support for the use of HP as an antidepressant and these results are similar to results reported from the Northern hemisphere. The results of all these studies suggest that the quality of the locally produced tincture is similar in efficacy to that of the standardised product of the Northern hemisphere.
- Full Text:
- Date Issued: 2005
- Authors: Stephens, Linda Lee
- Date: 2005
- Subjects: Hypericum perforatum -- Physiological effect Hypericum perforatum -- Therapeutic use Antidepressants
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3793 , http://hdl.handle.net/10962/d1003271
- Description: Hypericum perforatum is a herbal medicine that has been used for centuries for the treatment of depression. Many studies have been conducted in the Northern hemisphere on the efficacy of the HP extracts produced there. These studies include clinical trials and pharmacological investigations using a standardised HP extract or a fraction of the HP extract containing certain compounds, such as hypericin, pseudohypericin, hyperforin and several of the flavonoids thought to be responsible for the antidepressant activity. The mechanism of action of HP and its constituents is still not completely clear and it is speculated that the antidepressant activity is the result of several of the compounds acting synergistically. HP is indigenous to and also cultivated in the Western Cape of South Africa. Extracts from these plants are sold in the local health shops and there are no previous studies evaluating the efficacy of these products. The aim of this thesis is to investigate the antidepressant activity of one of these products and two of its constituents, quercetin and caffeic acid, to gain further insight into their mode of antidepressant action and to compare these results with similar studies which used a standardised extract produced in the northern hemisphere. The first study investigated the effect of HP, quercetin and caffeic acid on pineal metabolism. Changes in the synthesis of melatonin produced by the pineal gland have been implicated in depression. The results showed an increase in the level of melatonin produced in the animals treated with quercetin, which suggests that this compound may mediate antidepressant activity through such a mechanism. There are no previous reports on the in vivo effects of HP or any of its constituents on pineal metabolism. The second study investigated the effect of HP, quercetin and caffeic acid on the activity of the liver enzyme, tryptophan-2,3-dioxygenase (TDO). Inhibition of this enzyme has been shown to increase plasma levels of tryptophan, a precursor of serotonin and thereby result in increased serotonin levels in the brain. Low levels of serotonin in the brain have been implicated in depression. This study revealed significant inhibition of TDO by caffeic acid and this suggests that this constituent of HP could be contributing to its antidepressant activity through such a mechanism. There are no previous reports investigating the in vivo effect of HP or any of its constituents on TDO activity. Modulation of the levels of indoleamines, serotonin (5-HT) and dopamine (DA) as well as the metabolites, 3,4 dihydroxyphenyl acetic acid (DOPAC), 5-hydroxyindole acetic acid (5-HIAA) and homovallinic acid (HVA) in the brain have been implicated in the neuropharmacology of depression. Different studies using enzyme-linked immunosorbant assay (ELISA), high performance liquid chromatography with electrochemical detection (HPLC-ECD) and liquid chromatography-mass spectrometry (LC-MS) were used to determine changes in the levels of these indoleamines brought about after treatment with HP caffeic acid and quercetin. The results of the ELISA study showed significant increases in 5-HT levels in the brains of the animals treated with caffeic acid and quercetin. The results of the HPLC-ECD studies also revealed significant increases in 5-HT levels and a decrease in the turnover of 5-HT in the animals treated with quercetin. A significant increase in DA levels in the animals treated with quercetin was shown in both the HPLC-ECD and LC-MS studies. There was also an increase in DA turnover in the animals treated with HP shown in the HPLC-ECD and LC-MS studies. These results suggest that HP and its constituents, quercetin and caffeic acid mediate their antidepressant effects through serotonergic and dopaminergic neurotransmission. Adaptive changes in the density of b-adrenergic (b-AR), 5-HT2 and N-methyl-D-aspartate (NMDA) receptors have been implicated in depression. Several studies, investigating the effect of treatment with HP and quercetin on these different receptor densities, were undertaken using radioactive binding assays. Treatment with HP resulted in significant down regulation of b-AR and NMDA receptor densities and up-regulation of 5HT2 receptors. The effects on the b-AR and 5-HT2 receptors are similar to the results reported using HP in the Northern hemisphere, but the effect on the NMDA receptors is novel providing insight into the mode of action of HP. Apoptosis of neuronal cells has been implicated in neuro-degenerative and depressive disorders. Detection of apoptosis, using fluorescent microscopy observed through the labelling of DNA strand breaks, showed a decrease in the amount of apoptosis in the animals treated with HP and quercetin. This adds further support for the use of HP as an antidepressant and these results are similar to results reported from the Northern hemisphere. The results of all these studies suggest that the quality of the locally produced tincture is similar in efficacy to that of the standardised product of the Northern hemisphere.
- Full Text:
- Date Issued: 2005