The heuristic significance of enacted visualisation
- Authors: Samson, Duncan Alistair
- Date: 2012
- Subjects: Heuristic Visualization Problem solving Pattern perception Problem solving -- Ability testing Mathematics -- Study and teaching Education -- Research Interdisciplinary approach to knowledge
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1552 , http://hdl.handle.net/10962/d1003434
- Description: This study is centred on an analysis of pupils' lived experience while engaged in the generalisation of linear sequences/progressions presented in a pictorial context. The study is oriented within the conceptual framework of qualitative research, and is anchored within an interpretive paradigm. A case study methodological strategy was adopted, the research participants being the members of a mixed gender, high ability Grade 9 class of 23 pupils at an independent school in South Africa. The analytical framework is structured around a combination of complementary multiple perspectives provided by three theoretical ideas, enactivism, figural apprehension, and knowledge objectification. An important aspect of this analytical framework is the sensitivity it shows to the visual, phenomenological and semiotic aspects of figural pattern generalisation. It is the central thesis of this study that the combined complementary multiple perspectives of enactivism, figural apprehension and knowledge objectification provide a powerful depth of analysis to the exploration of the inter-relationship between the embodied processes of pattern generalisation and the visualisation of pictorial cues. The richly textured tapestry of activity captured through a multi-systemic semiotic analysis of participants' generalisation activity stands testament to this central thesis. Insights gleaned from this study are presented as practical strategies which support and encourage a multiple representational approach to pattern generalisation in the pedagogical context of the classroom.
- Full Text:
- Date Issued: 2012
- Authors: Samson, Duncan Alistair
- Date: 2012
- Subjects: Heuristic Visualization Problem solving Pattern perception Problem solving -- Ability testing Mathematics -- Study and teaching Education -- Research Interdisciplinary approach to knowledge
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1552 , http://hdl.handle.net/10962/d1003434
- Description: This study is centred on an analysis of pupils' lived experience while engaged in the generalisation of linear sequences/progressions presented in a pictorial context. The study is oriented within the conceptual framework of qualitative research, and is anchored within an interpretive paradigm. A case study methodological strategy was adopted, the research participants being the members of a mixed gender, high ability Grade 9 class of 23 pupils at an independent school in South Africa. The analytical framework is structured around a combination of complementary multiple perspectives provided by three theoretical ideas, enactivism, figural apprehension, and knowledge objectification. An important aspect of this analytical framework is the sensitivity it shows to the visual, phenomenological and semiotic aspects of figural pattern generalisation. It is the central thesis of this study that the combined complementary multiple perspectives of enactivism, figural apprehension and knowledge objectification provide a powerful depth of analysis to the exploration of the inter-relationship between the embodied processes of pattern generalisation and the visualisation of pictorial cues. The richly textured tapestry of activity captured through a multi-systemic semiotic analysis of participants' generalisation activity stands testament to this central thesis. Insights gleaned from this study are presented as practical strategies which support and encourage a multiple representational approach to pattern generalisation in the pedagogical context of the classroom.
- Full Text:
- Date Issued: 2012
The ichthyofauna of the Wilderness Lakes System, Western Cape, with particular emphasis on alien fish species and their establishment success
- Authors: Olds, Alexis Amy
- Date: 2012
- Subjects: Introduced fishes -- South Africa -- Wilderness , Estuarine fishes -- South Africa -- Wilderness , Mozambique tilapia -- South Africa -- Wilderness , Western mosquitofish -- South Africa -- Wilderness , Carp -- South Africa -- Wilderness , Largemouth bass -- South Africa -- Wilderness , Estuarine fishes -- Effect of exotic animals on -- South Africa -- Wilderness , Fish communities -- South Africa -- Wilderness
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5288 , http://hdl.handle.net/10962/d1005132 , Introduced fishes -- South Africa -- Wilderness , Estuarine fishes -- South Africa -- Wilderness , Mozambique tilapia -- South Africa -- Wilderness , Western mosquitofish -- South Africa -- Wilderness , Carp -- South Africa -- Wilderness , Largemouth bass -- South Africa -- Wilderness , Estuarine fishes -- Effect of exotic animals on -- South Africa -- Wilderness , Fish communities -- South Africa -- Wilderness
- Description: Freshwater fish species have been introduced into freshwater systems around the world, primarily for aquaculture, ornamental fish trade and sport fishing. Their introduction into estuarine systems is uncommon however, instances do occur and their establishment success and impacts on these estuarine systems is not well documented. The extent of invasion by four freshwater fishes in a RAMSAR listed estuarine system, the Wilderness Lakes, Western Cape was investigated. This thesis determined the relative abundance and distribution of alien fishes in relation to the native fish biota, their establishment success in the system, what factors inhibited their establishment and whether the introduction of alien fishes negatively impacted the native fish biota. The distribution and abundance of fishes were assessed primarily using fyke nets, seine nets and gill nets in each of the lakes, interconnecting channels and the Touw Estuary. The fish fauna was made up of euryhaline marine species comprising 46%, native estuarine species comprising 18%, catadromous species comprising 7% and freshwater alien species comprising 29% of the total biomass sampled. A total of 26 species were sampled in the system, three of which were considered alien; Oreochromis mossambicus, Gambusia affinis and Cyprinus carpio, and Micropterus salmoides were not sampled but confirmed in the system. Establishment success was determined by evidence of: a sustainable breeding population, a wide distribution, abundant in the sampling area, and all size classes of fish sampled. Gambusia affinis and Oreochromis mossambicus have been recorded in the system for a minimum of 13 and 26 years respectively. They were widely distributed and highly abundant and are established in the system. Micropterus salmoides was first recorded in the system in 1985 but abundances have remained low with fish appearing to be limited to Island Lake and Langvlei. Reproduction appeared to be limited by higher salinity and these factors indicated that this was a casual species which relies on repeated introductions for population maintenance. Cyprinus carpio spawned successfully in 2010 and was widely distributed but abundances were still low with a total of 15 fish being sampled throughout the system, and was thus in the establishing phase. As these are considered freshwater alien species, the physico-chemical parameters in the estuarine environment inhibiting the establishment success of the alien fishes were investigated. Gambusia affinis and O. mossambicus were not limited by the physical environment, and while O. mossambicus cannot tolerate temperatures below 11⁰C, temperatures only dropped below its tolerance for a total of two days between February 2010 and February 2011. Cyprinus carpio and M. salmoides were restricted by salinity in Rondevlei and Langvlei but could tolerate salinity in Island Lake and the Touw Estuary during closed mouth phases. While adults appeared to tolerate the salinity in the system, egg and larval development could be affected thus reducing the viability of the population. The abundance of alien fishes did not negatively impact the abundance of native fish species. The interactions between the native and alien fish biota tended towards biotic acceptance where, as alien abundance increased so did native fish abundance. The impacts of the alien fishes on the native fish biota were assessed by comparing the fish community from a study completed in 1985 to the findings of this study. From these two studies there were no apparent negative impacts on the native fish biota and the fish community composition would most likely be structured by estuarine mouth opening events.
- Full Text:
- Date Issued: 2012
- Authors: Olds, Alexis Amy
- Date: 2012
- Subjects: Introduced fishes -- South Africa -- Wilderness , Estuarine fishes -- South Africa -- Wilderness , Mozambique tilapia -- South Africa -- Wilderness , Western mosquitofish -- South Africa -- Wilderness , Carp -- South Africa -- Wilderness , Largemouth bass -- South Africa -- Wilderness , Estuarine fishes -- Effect of exotic animals on -- South Africa -- Wilderness , Fish communities -- South Africa -- Wilderness
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5288 , http://hdl.handle.net/10962/d1005132 , Introduced fishes -- South Africa -- Wilderness , Estuarine fishes -- South Africa -- Wilderness , Mozambique tilapia -- South Africa -- Wilderness , Western mosquitofish -- South Africa -- Wilderness , Carp -- South Africa -- Wilderness , Largemouth bass -- South Africa -- Wilderness , Estuarine fishes -- Effect of exotic animals on -- South Africa -- Wilderness , Fish communities -- South Africa -- Wilderness
- Description: Freshwater fish species have been introduced into freshwater systems around the world, primarily for aquaculture, ornamental fish trade and sport fishing. Their introduction into estuarine systems is uncommon however, instances do occur and their establishment success and impacts on these estuarine systems is not well documented. The extent of invasion by four freshwater fishes in a RAMSAR listed estuarine system, the Wilderness Lakes, Western Cape was investigated. This thesis determined the relative abundance and distribution of alien fishes in relation to the native fish biota, their establishment success in the system, what factors inhibited their establishment and whether the introduction of alien fishes negatively impacted the native fish biota. The distribution and abundance of fishes were assessed primarily using fyke nets, seine nets and gill nets in each of the lakes, interconnecting channels and the Touw Estuary. The fish fauna was made up of euryhaline marine species comprising 46%, native estuarine species comprising 18%, catadromous species comprising 7% and freshwater alien species comprising 29% of the total biomass sampled. A total of 26 species were sampled in the system, three of which were considered alien; Oreochromis mossambicus, Gambusia affinis and Cyprinus carpio, and Micropterus salmoides were not sampled but confirmed in the system. Establishment success was determined by evidence of: a sustainable breeding population, a wide distribution, abundant in the sampling area, and all size classes of fish sampled. Gambusia affinis and Oreochromis mossambicus have been recorded in the system for a minimum of 13 and 26 years respectively. They were widely distributed and highly abundant and are established in the system. Micropterus salmoides was first recorded in the system in 1985 but abundances have remained low with fish appearing to be limited to Island Lake and Langvlei. Reproduction appeared to be limited by higher salinity and these factors indicated that this was a casual species which relies on repeated introductions for population maintenance. Cyprinus carpio spawned successfully in 2010 and was widely distributed but abundances were still low with a total of 15 fish being sampled throughout the system, and was thus in the establishing phase. As these are considered freshwater alien species, the physico-chemical parameters in the estuarine environment inhibiting the establishment success of the alien fishes were investigated. Gambusia affinis and O. mossambicus were not limited by the physical environment, and while O. mossambicus cannot tolerate temperatures below 11⁰C, temperatures only dropped below its tolerance for a total of two days between February 2010 and February 2011. Cyprinus carpio and M. salmoides were restricted by salinity in Rondevlei and Langvlei but could tolerate salinity in Island Lake and the Touw Estuary during closed mouth phases. While adults appeared to tolerate the salinity in the system, egg and larval development could be affected thus reducing the viability of the population. The abundance of alien fishes did not negatively impact the abundance of native fish species. The interactions between the native and alien fish biota tended towards biotic acceptance where, as alien abundance increased so did native fish abundance. The impacts of the alien fishes on the native fish biota were assessed by comparing the fish community from a study completed in 1985 to the findings of this study. From these two studies there were no apparent negative impacts on the native fish biota and the fish community composition would most likely be structured by estuarine mouth opening events.
- Full Text:
- Date Issued: 2012
The impact of clothing and protective gear on biophysical, physiological, perceptual and performance responses of rugby players during a simulated rugby protocol
- Authors: Cannon, Michael-John
- Date: 2012
- Subjects: Protective clothing -- Rugby football -- Health aspects -- Research , Rugby football injuries -- Prevention -- Research , Sports injuries -- Prevention -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5124 , http://hdl.handle.net/10962/d1005202 , Protective clothing -- Rugby football -- Health aspects -- Research , Rugby football injuries -- Prevention -- Research , Sports injuries -- Prevention -- Research
- Description: Background: Clothing and protective gear worn during intermittent exercise has shown to increase physiological and perceptual responses, and negatively impact performance capacities, due to increased heat strain, suggested to hasten the onset of fatigue. However, the mechanisms of fatigue experienced in rugby remain unclear. Objectives: The aim of this study was establish whether clothing and protective gear worn during a simulated rugby protocol impacts players‘ biophysical, physiological, perceptual and performance responses. Methods: 15 registered university and school first XV rugby players with a mean (± SD) age of 20.9 years (± 1.9) volunteered to participate in the study. Testing was performed in a controlled laboratory setting, with temperatures having to be within the range of 16º C-22º C. The mean (± SD) ambient temperature was 17.6º C (± 1.6) for the control condition and 17.3º C (1.5) for the experimental condition. The mean (± SD) relative humidity was 65.2 % (± 9.5) for the control condition and 66.3 % (± 10.0) for the experimental condition. Player‘s performed two protocols of 80-minutes; a control condition (minimal clothing and protective gear) and an experimental condition (full clothing and protective gear). Physiological, perceptual and performance responses were measured at set intervals during the protocol, while biophysical responses were measured pre-, at half-time and post-protocol during a 3-minute EMG treadmill protocol. Results: Muscle activity significantly (p< 0.05) increased with increasing running speeds. There were no significant (p> 0.05) differences for muscle activity between conditions, except for the semitendinosus muscle, which was significantly (p< 0.05) higher during the control condition while running at high speeds. Players‘ heart rates, core temperatures and perceptual responses were significantly (p< 0.05) higher during the experimental condition, compared to the control condition. Performance responses were significantly (p< 0.05) lower during the experimental condition. Conclusion: The main driver of physiological and perceptual responses was the exercise itself. However, the additional clothing and protective gear exacerbated the responses, particularly towards the end stages of the protocol. This negatively impacted players‘ performance. Muscle activity appeared to be unaffected by increased body temperatures. However, core temperatures never reached critically high levels during either condition.
- Full Text:
- Date Issued: 2012
- Authors: Cannon, Michael-John
- Date: 2012
- Subjects: Protective clothing -- Rugby football -- Health aspects -- Research , Rugby football injuries -- Prevention -- Research , Sports injuries -- Prevention -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5124 , http://hdl.handle.net/10962/d1005202 , Protective clothing -- Rugby football -- Health aspects -- Research , Rugby football injuries -- Prevention -- Research , Sports injuries -- Prevention -- Research
- Description: Background: Clothing and protective gear worn during intermittent exercise has shown to increase physiological and perceptual responses, and negatively impact performance capacities, due to increased heat strain, suggested to hasten the onset of fatigue. However, the mechanisms of fatigue experienced in rugby remain unclear. Objectives: The aim of this study was establish whether clothing and protective gear worn during a simulated rugby protocol impacts players‘ biophysical, physiological, perceptual and performance responses. Methods: 15 registered university and school first XV rugby players with a mean (± SD) age of 20.9 years (± 1.9) volunteered to participate in the study. Testing was performed in a controlled laboratory setting, with temperatures having to be within the range of 16º C-22º C. The mean (± SD) ambient temperature was 17.6º C (± 1.6) for the control condition and 17.3º C (1.5) for the experimental condition. The mean (± SD) relative humidity was 65.2 % (± 9.5) for the control condition and 66.3 % (± 10.0) for the experimental condition. Player‘s performed two protocols of 80-minutes; a control condition (minimal clothing and protective gear) and an experimental condition (full clothing and protective gear). Physiological, perceptual and performance responses were measured at set intervals during the protocol, while biophysical responses were measured pre-, at half-time and post-protocol during a 3-minute EMG treadmill protocol. Results: Muscle activity significantly (p< 0.05) increased with increasing running speeds. There were no significant (p> 0.05) differences for muscle activity between conditions, except for the semitendinosus muscle, which was significantly (p< 0.05) higher during the control condition while running at high speeds. Players‘ heart rates, core temperatures and perceptual responses were significantly (p< 0.05) higher during the experimental condition, compared to the control condition. Performance responses were significantly (p< 0.05) lower during the experimental condition. Conclusion: The main driver of physiological and perceptual responses was the exercise itself. However, the additional clothing and protective gear exacerbated the responses, particularly towards the end stages of the protocol. This negatively impacted players‘ performance. Muscle activity appeared to be unaffected by increased body temperatures. However, core temperatures never reached critically high levels during either condition.
- Full Text:
- Date Issued: 2012
The implications of rural-urban migration on employment and household income with particular reference to Lesotho
- Authors: Damane, Moeti
- Date: 2012
- Subjects: Rural-urban migration -- Employment -- Lesotho Informal sector (Economics) -- Lesotho Lesotho -- Economic conditions
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1002 , http://hdl.handle.net/10962/d1002737
- Description: The research investigates the impact of internal rural - urban migration III Lesotho on household income and employment. Using data gathered from the 2002/03 household survey, the 2006 nationwide census and a questionnaire on rural - urban migration in Lesotho administered to 500 respondents in Maseru and Leribe, we estimate a logit model of the probability of employment in Lesotho in 2008 given a set of independent variables. The independent variables are respondent's work experience; years of education completed; employment status in 2004; employment status in 2008; gender; job skill level; place of residence in 2004 and a categorical variable that measures whether or not the respondent is a rural - urban migrant. The results suggest that migration and work experience have no significant impact on an individual's likelihood of being employed in the country's formal sector. Also, it was found that the higher the level of education an individual has, the less likely are their chances of employment in the country's formal sector because of the lack of formal jobs in the urban areas. Over 50% of Lesotho's workforce employed in the urban areas was discovered to work in the informal sector. The study concludes that there is a lack of jobs in Lesotho's urban formal sector that results in a thriving informal sector. The advantages of informal sector jobs to the rural - urban migrant include an increase in their standard of living as well as that of their family members left behind in the rural areas but the disadvantages include low levels of investor confidence that lead to a decrease in overall economic development and growth in the country.
- Full Text:
- Date Issued: 2012
- Authors: Damane, Moeti
- Date: 2012
- Subjects: Rural-urban migration -- Employment -- Lesotho Informal sector (Economics) -- Lesotho Lesotho -- Economic conditions
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1002 , http://hdl.handle.net/10962/d1002737
- Description: The research investigates the impact of internal rural - urban migration III Lesotho on household income and employment. Using data gathered from the 2002/03 household survey, the 2006 nationwide census and a questionnaire on rural - urban migration in Lesotho administered to 500 respondents in Maseru and Leribe, we estimate a logit model of the probability of employment in Lesotho in 2008 given a set of independent variables. The independent variables are respondent's work experience; years of education completed; employment status in 2004; employment status in 2008; gender; job skill level; place of residence in 2004 and a categorical variable that measures whether or not the respondent is a rural - urban migrant. The results suggest that migration and work experience have no significant impact on an individual's likelihood of being employed in the country's formal sector. Also, it was found that the higher the level of education an individual has, the less likely are their chances of employment in the country's formal sector because of the lack of formal jobs in the urban areas. Over 50% of Lesotho's workforce employed in the urban areas was discovered to work in the informal sector. The study concludes that there is a lack of jobs in Lesotho's urban formal sector that results in a thriving informal sector. The advantages of informal sector jobs to the rural - urban migrant include an increase in their standard of living as well as that of their family members left behind in the rural areas but the disadvantages include low levels of investor confidence that lead to a decrease in overall economic development and growth in the country.
- Full Text:
- Date Issued: 2012
The integration of mapwork and environmental issues using local context in FET Geography: an investigation of current pedagogic practices to inform professional development
- Authors: Batyi, Kekeletso Rejoyce
- Date: 2012
- Subjects: Geography -- South Africa -- Grahamstown -- Study and teaching (Secondary) Maps -- Study and teaching (Secondary) -- South Africa -- Grahamstown Environmental education -- Study and teaching (Secondary) -- South Africa -- Grahamstown Teachers -- Training of -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1580 , http://hdl.handle.net/10962/d1003462
- Description: This is an interpretative case study of four Grahamstown Education District Further Education and Training (FET) schools. The study sets out to investigate how Geography teachers integrate mapwork and environmental issues using local context, with the intention of providing insights for future professional development. Data for this study were generated using qualitative methods such as document analysis, semi-structured interviews and lesson observations. Interviews were conducted with geography teachers, the subject advisor and a workshop facilitator. The evidence generated in the study revealed that contrary to the integrative design of the curriculum, there is a superficial integration of mapwork and environmental issues as well as a cursory reference to and use of local context. This was noted in both professional development support workshops and classroom practice. The study finds that efforts to improve performance in geography need to pay closer attention to curriculum policy that calls for an integration and localization of knowledge and skills for coherence and relevance. It also notes that there is a need for a focus on real-world problem solving in social, economic, cultural and physical environments through the use of inquiry-based local fieldwork. Local investigations provide an integrative space for content and skills as well as being an important point of reference from which learners can compare and contrast issues in other places such as provincial, national, continental, and global locations. A professional development programme that emphasizes integration and contextualization alongside the current focus on basic skills training is proposed to improve what teachers are delivering in the classroom and to support enquiry-based fieldwork and research to strengthen a place-based relevance in local, national and international contexts. Finally an exemplar for professional development is briefly developed for the topic of soil erosion.
- Full Text:
- Date Issued: 2012
- Authors: Batyi, Kekeletso Rejoyce
- Date: 2012
- Subjects: Geography -- South Africa -- Grahamstown -- Study and teaching (Secondary) Maps -- Study and teaching (Secondary) -- South Africa -- Grahamstown Environmental education -- Study and teaching (Secondary) -- South Africa -- Grahamstown Teachers -- Training of -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1580 , http://hdl.handle.net/10962/d1003462
- Description: This is an interpretative case study of four Grahamstown Education District Further Education and Training (FET) schools. The study sets out to investigate how Geography teachers integrate mapwork and environmental issues using local context, with the intention of providing insights for future professional development. Data for this study were generated using qualitative methods such as document analysis, semi-structured interviews and lesson observations. Interviews were conducted with geography teachers, the subject advisor and a workshop facilitator. The evidence generated in the study revealed that contrary to the integrative design of the curriculum, there is a superficial integration of mapwork and environmental issues as well as a cursory reference to and use of local context. This was noted in both professional development support workshops and classroom practice. The study finds that efforts to improve performance in geography need to pay closer attention to curriculum policy that calls for an integration and localization of knowledge and skills for coherence and relevance. It also notes that there is a need for a focus on real-world problem solving in social, economic, cultural and physical environments through the use of inquiry-based local fieldwork. Local investigations provide an integrative space for content and skills as well as being an important point of reference from which learners can compare and contrast issues in other places such as provincial, national, continental, and global locations. A professional development programme that emphasizes integration and contextualization alongside the current focus on basic skills training is proposed to improve what teachers are delivering in the classroom and to support enquiry-based fieldwork and research to strengthen a place-based relevance in local, national and international contexts. Finally an exemplar for professional development is briefly developed for the topic of soil erosion.
- Full Text:
- Date Issued: 2012
The isolation, quantification and synthetic modification of antiplasmodial natural products from sargassum heterophyllum
- Authors: Munedzimwe, Tatenda Carol
- Date: 2012
- Subjects: Malaria -- Developing countries -- Prevention , Antimalarials
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3871 , http://hdl.handle.net/10962/d1018252
- Description: Malaria is one of the most deadly parasitic diseases known to man. Although the number of malaria cases reported each year is decreasing, this disease continues to pose health and economic problems mainly in developing countries. Significant progress has been made in the fight against this disease. This includes the discovery and development of potent antimalarial agents. However, the development of resistance to most of these potent antimalarials has made the development of new antiplasmodial agents of paramount importance. Several promising antiplasmodial agents have been found from the marine environment. Amongst these are the tetraprenylated toluquinols from the brown alga: Sargassum heterophyllum. These metabolites have been reported to exhibit a range of antiplasmodial activity; however, the mechanisms by which these compounds bring about their antiplasmodial activity and the pharmacophoric groups responsible for such activity are unknown. Two species of Sargassum algae were encountered during the course of this project. From the investigation of the geographical and seasonal variation of metabolites of S. heterophyllum and S. elegans we established that there were no significant intra and inter site variations amongst metabolite profiles of both species both within and between the sampled seasons. These results enabled us to establish that the collection of both species from three different sites on the eastern coast of South Africa namely; Kenton on Sea, Port Alfred and Noordhoek in autumn, winter or spring would qualitatively yield the same metabolites. A comparison of metabolite profiles of both species also revealed no qualitative differences between metabolites of S. heterophyllum and S. elegans. The quantities of selected prenylated metabolites extracted from S. heterophyllum using four different extraction techniques was also assessed using qNMR as the method of quantification. This led to the identification of optimal extraction techniques and conditions for the extraction of sargahydroquinoic acid (1.38), sargaquinoic aid (1.39) and sargachromenol (2.10) from S. heterophyllum. From this study, the extraction of algae by soxhlet extraction using EtOH as the extraction solvent led to the extraction of the highest quantities of sargahydroquinoic acid. The potential of other extraction techniques such as microwave assisted extraction, to yield high quantities of the selected metabolites were also identified. With gram quantities of sargahydroquinoic acid (1.38) in hand, this compound was modified by oxidation, reduction, acetylation, methylation and cyclization reactions to yield nine derivatives. The derivatives and four naturally occurring prenylated toluquinols were assessed for antiplasmodial and cytotoxic activity against the FCR-3 Gambian Chloroquine resistant strain of P. falciparum and the MDA-MB-231 breast carcinoma cell line respectively. Comparison of antiplasmodial data for all twelve compounds showed that the hydroquinone moeity of sargahydroquinoic acid (1.38) is important for antiplasmodial activity while esterification of the carboxylic acid group in 1.38 resulted in more potent antiplasmodial compounds. Of all twelve compounds, compound 5.2, the hydroquinone methyl ester of 1.38 was found to be the most potent antiplasmodial compound with an IC₅₀ value of 1.94 μM and a selectivity index of 22.68.
- Full Text:
- Date Issued: 2012
- Authors: Munedzimwe, Tatenda Carol
- Date: 2012
- Subjects: Malaria -- Developing countries -- Prevention , Antimalarials
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3871 , http://hdl.handle.net/10962/d1018252
- Description: Malaria is one of the most deadly parasitic diseases known to man. Although the number of malaria cases reported each year is decreasing, this disease continues to pose health and economic problems mainly in developing countries. Significant progress has been made in the fight against this disease. This includes the discovery and development of potent antimalarial agents. However, the development of resistance to most of these potent antimalarials has made the development of new antiplasmodial agents of paramount importance. Several promising antiplasmodial agents have been found from the marine environment. Amongst these are the tetraprenylated toluquinols from the brown alga: Sargassum heterophyllum. These metabolites have been reported to exhibit a range of antiplasmodial activity; however, the mechanisms by which these compounds bring about their antiplasmodial activity and the pharmacophoric groups responsible for such activity are unknown. Two species of Sargassum algae were encountered during the course of this project. From the investigation of the geographical and seasonal variation of metabolites of S. heterophyllum and S. elegans we established that there were no significant intra and inter site variations amongst metabolite profiles of both species both within and between the sampled seasons. These results enabled us to establish that the collection of both species from three different sites on the eastern coast of South Africa namely; Kenton on Sea, Port Alfred and Noordhoek in autumn, winter or spring would qualitatively yield the same metabolites. A comparison of metabolite profiles of both species also revealed no qualitative differences between metabolites of S. heterophyllum and S. elegans. The quantities of selected prenylated metabolites extracted from S. heterophyllum using four different extraction techniques was also assessed using qNMR as the method of quantification. This led to the identification of optimal extraction techniques and conditions for the extraction of sargahydroquinoic acid (1.38), sargaquinoic aid (1.39) and sargachromenol (2.10) from S. heterophyllum. From this study, the extraction of algae by soxhlet extraction using EtOH as the extraction solvent led to the extraction of the highest quantities of sargahydroquinoic acid. The potential of other extraction techniques such as microwave assisted extraction, to yield high quantities of the selected metabolites were also identified. With gram quantities of sargahydroquinoic acid (1.38) in hand, this compound was modified by oxidation, reduction, acetylation, methylation and cyclization reactions to yield nine derivatives. The derivatives and four naturally occurring prenylated toluquinols were assessed for antiplasmodial and cytotoxic activity against the FCR-3 Gambian Chloroquine resistant strain of P. falciparum and the MDA-MB-231 breast carcinoma cell line respectively. Comparison of antiplasmodial data for all twelve compounds showed that the hydroquinone moeity of sargahydroquinoic acid (1.38) is important for antiplasmodial activity while esterification of the carboxylic acid group in 1.38 resulted in more potent antiplasmodial compounds. Of all twelve compounds, compound 5.2, the hydroquinone methyl ester of 1.38 was found to be the most potent antiplasmodial compound with an IC₅₀ value of 1.94 μM and a selectivity index of 22.68.
- Full Text:
- Date Issued: 2012
The jazz divas an analysis of the musical careers of six New Brighton vocalists
- Authors: Butete, Netsayi
- Date: 2012
- Subjects: Jazz musicians -- Research -- South Africa -- Port Elizabeth Ethnomusicology -- Research -- South Africa Sex discrimination against women -- South Africa Sex discrimination in employment -- South Africa Apartheid -- South Africa
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2633 , http://hdl.handle.net/10962/d1002298
- Description: There has been insufficient academic research on the music of the Eastern Cape in general and Port Elizabeth and New Brighton in particular. This study, as part of the International Library of African Music (ILAM)lRed Location Museum Music History Project (ILAMIRLMHP) - an oral history intervention to save the music history of New Brighton from extinction through research and documentation of the memories of veteran musicians - is focused on jazz vocalists. The primary objective of my study is to investigate, critically analyze, interpret and document the career experiences of six New Brighton jazz vocalists in the context of performing in the Port Elizabeth music industry during the apartheid and the post-apartheid eras. The secondary objectives are to stimulate research interests in music students and ethnomusicologists to pursue research on the music of Port Elizabeth and the Eastern Cape and to inspire and motivate the vocalists to continue making music with renewed zeal. A qualitative research paradigm informed the field research necessary for this study. The fieldwork paved the way for an eclectic framework of analysis grounded in Pierre Bourdieu's notions of habitus, field and capital, examining the impact of the context on the vocalists' habitus which influenced how they viewed and interpreted their past and current experiences in the performance field. Data obtained through extensive interviewing of New Brighton's contemporary female vocalists and their male counterparts revealed that they have no opportunity to make commercial recordings. The musicians have to migrate to Johannesburg to have successful music careers, although personality politics, greed and lack of professionalism also work against the musicians' success. The data shows that New Brighton musicians, both male and female, do not have enough performance opportunities and there are fewer chances to tour now than there were from the 1960s through the 1980s. As in the apartheid era, female vocalists are still discriminated against in terms of pay, and men discriminate in how they pay other male musicians. Analysis of the vocalists' jazz compositions revealed that their song lyrics depict a bona fide urban African culture and reflect the emotional needs of the society in which they live.
- Full Text:
- Date Issued: 2012
- Authors: Butete, Netsayi
- Date: 2012
- Subjects: Jazz musicians -- Research -- South Africa -- Port Elizabeth Ethnomusicology -- Research -- South Africa Sex discrimination against women -- South Africa Sex discrimination in employment -- South Africa Apartheid -- South Africa
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2633 , http://hdl.handle.net/10962/d1002298
- Description: There has been insufficient academic research on the music of the Eastern Cape in general and Port Elizabeth and New Brighton in particular. This study, as part of the International Library of African Music (ILAM)lRed Location Museum Music History Project (ILAMIRLMHP) - an oral history intervention to save the music history of New Brighton from extinction through research and documentation of the memories of veteran musicians - is focused on jazz vocalists. The primary objective of my study is to investigate, critically analyze, interpret and document the career experiences of six New Brighton jazz vocalists in the context of performing in the Port Elizabeth music industry during the apartheid and the post-apartheid eras. The secondary objectives are to stimulate research interests in music students and ethnomusicologists to pursue research on the music of Port Elizabeth and the Eastern Cape and to inspire and motivate the vocalists to continue making music with renewed zeal. A qualitative research paradigm informed the field research necessary for this study. The fieldwork paved the way for an eclectic framework of analysis grounded in Pierre Bourdieu's notions of habitus, field and capital, examining the impact of the context on the vocalists' habitus which influenced how they viewed and interpreted their past and current experiences in the performance field. Data obtained through extensive interviewing of New Brighton's contemporary female vocalists and their male counterparts revealed that they have no opportunity to make commercial recordings. The musicians have to migrate to Johannesburg to have successful music careers, although personality politics, greed and lack of professionalism also work against the musicians' success. The data shows that New Brighton musicians, both male and female, do not have enough performance opportunities and there are fewer chances to tour now than there were from the 1960s through the 1980s. As in the apartheid era, female vocalists are still discriminated against in terms of pay, and men discriminate in how they pay other male musicians. Analysis of the vocalists' jazz compositions revealed that their song lyrics depict a bona fide urban African culture and reflect the emotional needs of the society in which they live.
- Full Text:
- Date Issued: 2012
The life history and fishery assessment of largespot pompano, Trachinotus botla, in northern KwaZulu-Natal, South Africa
- Authors: Parker, Denham
- Date: 2012
- Subjects: Trachinotus -- South Africa -- KwaZulu-Natal , Carangidae -- South Africa -- KwaZulu-Natal , Fishing -- South Africa -- KwaZulu-Natal , Fishery management -- South Africa -- KwaZulu-Natal , Fishing -- Economic aspects -- South Africa -- KwaZulu-Natal , Fish stock assessment -- South Africa -- KwaZulu-Natal , Trachinotus -- Growth -- South Africa -- KwaZulu-Natal , Trachinotus -- Breeding -- South Africa -- KwaZulu-Natal , Trachinotus -- Food -- South Africa -- KwaZulu-Natal , Host-parasite relationships -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5296 , http://hdl.handle.net/10962/d1005141 , Trachinotus -- South Africa -- KwaZulu-Natal , Carangidae -- South Africa -- KwaZulu-Natal , Fishing -- South Africa -- KwaZulu-Natal , Fishery management -- South Africa -- KwaZulu-Natal , Fishing -- Economic aspects -- South Africa -- KwaZulu-Natal , Fish stock assessment -- South Africa -- KwaZulu-Natal , Trachinotus -- Growth -- South Africa -- KwaZulu-Natal , Trachinotus -- Breeding -- South Africa -- KwaZulu-Natal , Trachinotus -- Food -- South Africa -- KwaZulu-Natal , Host-parasite relationships -- South Africa -- KwaZulu-Natal
- Description: Largespot pompano, Trachinotus botla, is a surf zone carangid with a cosmopolitan distribution in subtropical and tropical waters. Within South Africa, the species occurs along the KwaZulu-Natal coastline where it is a popular recreational fishing target. Recreational fishing in southern Africa has developed significantly in recent years, and is now regarded as an industry with huge economic potential. The long-term contribution of South African recreational fisheries to local economies is reliant upon sustainable exploitation through effective management. Trachinotus botla was found to grow rapidly with maximum observed age of six years. Otolith growth zone deposition was validated using edge analysis. Growth was similar between males and females until ~350 mm FL after which females continued to grow while growth in males slowed. The resulting overall sex ratio was slightly female-biased (1 male: 1.3 females). Trachinotus botla matures early with all fish considered to be mature at 290 mm FL, which corresponds to an age of three years. A protracted spawning season was observed ranging from November to February and there was evidence to suggest that T. botla is a serial spawner. Dietary analysis indicates that T. botla is an opportunistic predator with a catholic diet. The opportunistic utilization of “superabundant” prey items is a fundamental characteristic of the species feeding habits. An ontogenetic dietary shift was observed at approximately 300 mm FL that was linked to a shift in habitat preference. This thesis provided the first evidence that infection by the tongue-replacing isopod, Cymothoa borbonica, reduces the growth rate of wild host fish populations despite not affecting the diet, feeding habits and feeding frequency of their hosts. These results also highlighted the inadequacy of condition factor as a proxy for quantifying the effects of cymothoids on their hosts, and identified the need to incorporate host age when assessing the effects of parasite infection. Information on the life-cycle of C. borbonica, including estimates of the hypothesized “infectious” period and its longevity were obtained through analysis of parasite infection patterns as a function of host age and length. An assessment of the T. botla shore fishery of KwaZulu-Natal using historical catch data revealed that the fishery is stable. Productivity of the T. botla fishery increased towards the north of KwaZulu-Natal. Distinct seasonal variations in the T. botla fishery were also noted with catches peaking in summer months and lowest during winter. A per-recruit assessment revealed that the species is currently underexploited (SBR = 62% of pristine levels), and fishing mortality rate could be doubled before reaching the spawner biomass-per recruit target reference point of FSB₄₀. A combination of the life history characteristics of species, the nature of the recreational shore fishery together with the current management regulation of 5 fish person⁻¹ day⁻¹ has ensured the sustainable utilization of the T. botla resource in KwaZulu-Natal.
- Full Text:
- Date Issued: 2012
- Authors: Parker, Denham
- Date: 2012
- Subjects: Trachinotus -- South Africa -- KwaZulu-Natal , Carangidae -- South Africa -- KwaZulu-Natal , Fishing -- South Africa -- KwaZulu-Natal , Fishery management -- South Africa -- KwaZulu-Natal , Fishing -- Economic aspects -- South Africa -- KwaZulu-Natal , Fish stock assessment -- South Africa -- KwaZulu-Natal , Trachinotus -- Growth -- South Africa -- KwaZulu-Natal , Trachinotus -- Breeding -- South Africa -- KwaZulu-Natal , Trachinotus -- Food -- South Africa -- KwaZulu-Natal , Host-parasite relationships -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5296 , http://hdl.handle.net/10962/d1005141 , Trachinotus -- South Africa -- KwaZulu-Natal , Carangidae -- South Africa -- KwaZulu-Natal , Fishing -- South Africa -- KwaZulu-Natal , Fishery management -- South Africa -- KwaZulu-Natal , Fishing -- Economic aspects -- South Africa -- KwaZulu-Natal , Fish stock assessment -- South Africa -- KwaZulu-Natal , Trachinotus -- Growth -- South Africa -- KwaZulu-Natal , Trachinotus -- Breeding -- South Africa -- KwaZulu-Natal , Trachinotus -- Food -- South Africa -- KwaZulu-Natal , Host-parasite relationships -- South Africa -- KwaZulu-Natal
- Description: Largespot pompano, Trachinotus botla, is a surf zone carangid with a cosmopolitan distribution in subtropical and tropical waters. Within South Africa, the species occurs along the KwaZulu-Natal coastline where it is a popular recreational fishing target. Recreational fishing in southern Africa has developed significantly in recent years, and is now regarded as an industry with huge economic potential. The long-term contribution of South African recreational fisheries to local economies is reliant upon sustainable exploitation through effective management. Trachinotus botla was found to grow rapidly with maximum observed age of six years. Otolith growth zone deposition was validated using edge analysis. Growth was similar between males and females until ~350 mm FL after which females continued to grow while growth in males slowed. The resulting overall sex ratio was slightly female-biased (1 male: 1.3 females). Trachinotus botla matures early with all fish considered to be mature at 290 mm FL, which corresponds to an age of three years. A protracted spawning season was observed ranging from November to February and there was evidence to suggest that T. botla is a serial spawner. Dietary analysis indicates that T. botla is an opportunistic predator with a catholic diet. The opportunistic utilization of “superabundant” prey items is a fundamental characteristic of the species feeding habits. An ontogenetic dietary shift was observed at approximately 300 mm FL that was linked to a shift in habitat preference. This thesis provided the first evidence that infection by the tongue-replacing isopod, Cymothoa borbonica, reduces the growth rate of wild host fish populations despite not affecting the diet, feeding habits and feeding frequency of their hosts. These results also highlighted the inadequacy of condition factor as a proxy for quantifying the effects of cymothoids on their hosts, and identified the need to incorporate host age when assessing the effects of parasite infection. Information on the life-cycle of C. borbonica, including estimates of the hypothesized “infectious” period and its longevity were obtained through analysis of parasite infection patterns as a function of host age and length. An assessment of the T. botla shore fishery of KwaZulu-Natal using historical catch data revealed that the fishery is stable. Productivity of the T. botla fishery increased towards the north of KwaZulu-Natal. Distinct seasonal variations in the T. botla fishery were also noted with catches peaking in summer months and lowest during winter. A per-recruit assessment revealed that the species is currently underexploited (SBR = 62% of pristine levels), and fishing mortality rate could be doubled before reaching the spawner biomass-per recruit target reference point of FSB₄₀. A combination of the life history characteristics of species, the nature of the recreational shore fishery together with the current management regulation of 5 fish person⁻¹ day⁻¹ has ensured the sustainable utilization of the T. botla resource in KwaZulu-Natal.
- Full Text:
- Date Issued: 2012
The making of business news in Africa: a case study of Cameroon Tribune newspaper
- Authors: Tawe, Ngamale Emmanuel
- Date: 2012
- Subjects: Journalism -- Cameroon Mass media -- Cameroon Journalism, Commercial -- Cameroon Cameroon Tribune (Cameroon) Journalism, Commercial -- Sociological aspects -- Cameroon Journalism, Commercial -- Social aspects -- Cameroon Journalism, Commercial -- Economic aspects -- Cameroon Journalism, Commercial -- Political aspects -- Cameroon Cameroon -- Economic conditions Elite (Social sciences)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3487 , http://hdl.handle.net/10962/d1002942
- Description: Since the emergence of business journalism as a genre within the broad spectrum of news reporting, most of the scholarly works into its development have focused on growth in the western (that is developed) world. This indicates that very limited research has been done in the field of business journalism in the developing economies. Thus there exist gaps in understanding the practice of business journalism in Africa and part of this is rooted in how the practice is defined. This study aims to shed light on the practice of business journalism in this African context. It explores the onset and development of business journalism and its evolution in Africa. The main focus in this case study was to understand the definition of business news in the specific context of the Cameroon Tribune. Individual in-depth interviews were used as the main (primary) data collection method along with observation and cursory reading as complementary (secondary) methods. This study is influenced by the sociology of news production which foregrounds theoretical frames such as news construction and gatekeeping. Findings from this study reveal that business news at the Cameroon Tribune is elitist, essentially defined around personality and, is in the most part, development news. Additional findings indicate that the absence of any editorial guidelines leaves most reporters secondguessing how to please management with socialised values mostly acquired through peer learning. In conclusion, this study advances the necessity for the Africanisation of business news. This would entail reporting financial, economic, consumer, and corporate affairs, from a vocabulary and composition context that unveils much exchange taking place in the lives of many Africans.
- Full Text:
- Date Issued: 2012
- Authors: Tawe, Ngamale Emmanuel
- Date: 2012
- Subjects: Journalism -- Cameroon Mass media -- Cameroon Journalism, Commercial -- Cameroon Cameroon Tribune (Cameroon) Journalism, Commercial -- Sociological aspects -- Cameroon Journalism, Commercial -- Social aspects -- Cameroon Journalism, Commercial -- Economic aspects -- Cameroon Journalism, Commercial -- Political aspects -- Cameroon Cameroon -- Economic conditions Elite (Social sciences)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3487 , http://hdl.handle.net/10962/d1002942
- Description: Since the emergence of business journalism as a genre within the broad spectrum of news reporting, most of the scholarly works into its development have focused on growth in the western (that is developed) world. This indicates that very limited research has been done in the field of business journalism in the developing economies. Thus there exist gaps in understanding the practice of business journalism in Africa and part of this is rooted in how the practice is defined. This study aims to shed light on the practice of business journalism in this African context. It explores the onset and development of business journalism and its evolution in Africa. The main focus in this case study was to understand the definition of business news in the specific context of the Cameroon Tribune. Individual in-depth interviews were used as the main (primary) data collection method along with observation and cursory reading as complementary (secondary) methods. This study is influenced by the sociology of news production which foregrounds theoretical frames such as news construction and gatekeeping. Findings from this study reveal that business news at the Cameroon Tribune is elitist, essentially defined around personality and, is in the most part, development news. Additional findings indicate that the absence of any editorial guidelines leaves most reporters secondguessing how to please management with socialised values mostly acquired through peer learning. In conclusion, this study advances the necessity for the Africanisation of business news. This would entail reporting financial, economic, consumer, and corporate affairs, from a vocabulary and composition context that unveils much exchange taking place in the lives of many Africans.
- Full Text:
- Date Issued: 2012
The participation of teachers in the management and decision-making of three schools in the Kavango region of Namibia: a case study
- Authors: Muronga, Michael Muduva
- Date: 2012
- Subjects: Educational leadership -- Namibia -- Kavango School management and organization -- Namibia -- Kavango Teachers -- Namibia -- Kavango Teacher participation in administration -- Namibia -- Kavango Teachers -- Training of -- Namibia -- Kavango
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1688 , http://hdl.handle.net/10962/d1003571
- Description: The purpose of the research was to investigate stakeholders’ perceptions and experiences of teachers’ participation in school management and decision-making. Teachers’ involvement is a contested issue in schools. The goal was to find out to what extent and in what way teachers participate in school issues, as well as gain insight and understanding on the effects of participation of teachers in schools and how principals enhance democratic practice for quality education. The research was a case study conducted within the interpretive qualitative paradigm. I used document analysis, semi-structured interviews and observation to collect data for validity purposes and to counter subjectivity. The findings revealed at least a significant progress in terms of the Education Act, no 16 of 2001 requirement, of teachers’ participation in management and decision-making in schools, which has been an issue in the past. The study revealed that decisions are taken after consultation through consensus. The study revealed that the participation approach promotes ownership and commitment of staff to higher performance and common goals. The findings emerged that participative management has advantages for achieving higher performance through collaboration, consultation, and broader participation. The foremost findings include school principals’ roles in enhancing a collegial management approach by delegating, sharing leadership and responsibilities, and establishing organisation structures and committees involving teachers. Meetings serve as a platform for communication and sharing of information with stakeholders. However, there were also signs of tensions amid school management teams (SMTs) and teachers on participation in school matters in all aspects. Furthermore, its time-consuming nature, authoritarianism and accountability emerged as major challenges affecting the implementation of the participative approach. In addition to that, the study revealed that lack of knowledge and skills, unwillingness to involve others and to participate affects the implementation of the theory. As a result, the study recommends to the policies makers and the Ministry of Education to organize training for all stakeholders on participative management to empower them. Moreover, the study recommends to regional managers, inspectors, and advisory teachers (AT) to provide information to institutions responsible for teacher training to accommodate the theory into their curriculum. School principals should undergo training programmes or in-service training for participative leadership purposes to enhance their leadership capacity and to carry out their responsibilities effectively.
- Full Text:
- Date Issued: 2012
- Authors: Muronga, Michael Muduva
- Date: 2012
- Subjects: Educational leadership -- Namibia -- Kavango School management and organization -- Namibia -- Kavango Teachers -- Namibia -- Kavango Teacher participation in administration -- Namibia -- Kavango Teachers -- Training of -- Namibia -- Kavango
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1688 , http://hdl.handle.net/10962/d1003571
- Description: The purpose of the research was to investigate stakeholders’ perceptions and experiences of teachers’ participation in school management and decision-making. Teachers’ involvement is a contested issue in schools. The goal was to find out to what extent and in what way teachers participate in school issues, as well as gain insight and understanding on the effects of participation of teachers in schools and how principals enhance democratic practice for quality education. The research was a case study conducted within the interpretive qualitative paradigm. I used document analysis, semi-structured interviews and observation to collect data for validity purposes and to counter subjectivity. The findings revealed at least a significant progress in terms of the Education Act, no 16 of 2001 requirement, of teachers’ participation in management and decision-making in schools, which has been an issue in the past. The study revealed that decisions are taken after consultation through consensus. The study revealed that the participation approach promotes ownership and commitment of staff to higher performance and common goals. The findings emerged that participative management has advantages for achieving higher performance through collaboration, consultation, and broader participation. The foremost findings include school principals’ roles in enhancing a collegial management approach by delegating, sharing leadership and responsibilities, and establishing organisation structures and committees involving teachers. Meetings serve as a platform for communication and sharing of information with stakeholders. However, there were also signs of tensions amid school management teams (SMTs) and teachers on participation in school matters in all aspects. Furthermore, its time-consuming nature, authoritarianism and accountability emerged as major challenges affecting the implementation of the participative approach. In addition to that, the study revealed that lack of knowledge and skills, unwillingness to involve others and to participate affects the implementation of the theory. As a result, the study recommends to the policies makers and the Ministry of Education to organize training for all stakeholders on participative management to empower them. Moreover, the study recommends to regional managers, inspectors, and advisory teachers (AT) to provide information to institutions responsible for teacher training to accommodate the theory into their curriculum. School principals should undergo training programmes or in-service training for participative leadership purposes to enhance their leadership capacity and to carry out their responsibilities effectively.
- Full Text:
- Date Issued: 2012
The praxis of responsible investment in South Africa: a holistic case study of Evolution One Fund
- Zaulochnaya Ya-Brouwer, Irina
- Authors: Zaulochnaya Ya-Brouwer, Irina
- Date: 2012
- Subjects: Social responsibility of business -- South Africa Investments -- Moral and ethical aspects -- South Africa Institutional investments -- Moral and ethical aspects -- South Africa Private equity funds -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:778 , http://hdl.handle.net/10962/d1003899
- Description: At the beginning of the 21st century the public interest in environmental and social sustainability, and corporate governance grew exponentially fuelled by recurring ecological and financial crises. The market demand for cleaner production and corporate transparency created opportunities for sustainability entrepreneurs in a variety of industries, including financial markets and investment management. An increasing number of financial institutions across the world now offer ethical or socially responsible products to meet the environmental, social and governance (ESG) aspirations of their clients. In the US, according to the Social Investment Forum (SIF), responsible investment (RI) assets reached US$ 2,29 trillion in 2007 (Mitchell, 2008). The European Sustainable Investment Forum (EuroSIF) estimated that total European SRI assets reached EUR 5 trillion in 2009 (Wheelan, 2010). In June 2011 the International Finance Corporation (IFC) reported that at the end of 2010 professional sustainable investment under management in South Africa approximately equalled US$ 122,6 billion (IFC, 2011:44). The statistics describing the rapid growth in the ESG-type investments are, however, complicated by the variety of names and definitions used to describe this emerging type of investment and a general market uncertainty about what constitutes the practice of RI. The purpose of this case study is to better understand responsible investment principles and practice as seen through the eyes of a South African private equity fund, which specializes in clean technology.
- Full Text:
- Date Issued: 2012
- Authors: Zaulochnaya Ya-Brouwer, Irina
- Date: 2012
- Subjects: Social responsibility of business -- South Africa Investments -- Moral and ethical aspects -- South Africa Institutional investments -- Moral and ethical aspects -- South Africa Private equity funds -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:778 , http://hdl.handle.net/10962/d1003899
- Description: At the beginning of the 21st century the public interest in environmental and social sustainability, and corporate governance grew exponentially fuelled by recurring ecological and financial crises. The market demand for cleaner production and corporate transparency created opportunities for sustainability entrepreneurs in a variety of industries, including financial markets and investment management. An increasing number of financial institutions across the world now offer ethical or socially responsible products to meet the environmental, social and governance (ESG) aspirations of their clients. In the US, according to the Social Investment Forum (SIF), responsible investment (RI) assets reached US$ 2,29 trillion in 2007 (Mitchell, 2008). The European Sustainable Investment Forum (EuroSIF) estimated that total European SRI assets reached EUR 5 trillion in 2009 (Wheelan, 2010). In June 2011 the International Finance Corporation (IFC) reported that at the end of 2010 professional sustainable investment under management in South Africa approximately equalled US$ 122,6 billion (IFC, 2011:44). The statistics describing the rapid growth in the ESG-type investments are, however, complicated by the variety of names and definitions used to describe this emerging type of investment and a general market uncertainty about what constitutes the practice of RI. The purpose of this case study is to better understand responsible investment principles and practice as seen through the eyes of a South African private equity fund, which specializes in clean technology.
- Full Text:
- Date Issued: 2012
The role of culture in enabling or constraining the use of technology in higher education teaching and learning: the Commerce Curriculum Project
- Mostert, Markus, Snowball, Jeanette D, Boughey, Chrissie
- Authors: Mostert, Markus , Snowball, Jeanette D , Boughey, Chrissie
- Date: 2012
- Language: English
- Type: conference paper , text
- Identifier: http://hdl.handle.net/10962/61073 , vital:27945
- Description: This paper draws on a project located in one faculty at a South African university which aimed to use Information and Communication Technologies (ICTs) to enhance teaching and learning. More specifically, the paper uses Archer’s (1995, 1996, 2000, 1998) ‘analytical dualism’ and ‘morphogenesis’ to explore the way individuals involved in the project were able to exercise agency in departments which were relatively hostile to the goals they were aiming to pursue despite the wider cultural domain encompassing many ideas which construct the use of ICTs as significant in promoting student learning. The paper thus contributes to the culture/agency subtheme of the HECU6 conference. The paper begins by providing some background to the project before moving on to an exploration of the way Archer’s theoretical work was used to analyse data collected by project leaders.
- Full Text:
- Date Issued: 2012
- Authors: Mostert, Markus , Snowball, Jeanette D , Boughey, Chrissie
- Date: 2012
- Language: English
- Type: conference paper , text
- Identifier: http://hdl.handle.net/10962/61073 , vital:27945
- Description: This paper draws on a project located in one faculty at a South African university which aimed to use Information and Communication Technologies (ICTs) to enhance teaching and learning. More specifically, the paper uses Archer’s (1995, 1996, 2000, 1998) ‘analytical dualism’ and ‘morphogenesis’ to explore the way individuals involved in the project were able to exercise agency in departments which were relatively hostile to the goals they were aiming to pursue despite the wider cultural domain encompassing many ideas which construct the use of ICTs as significant in promoting student learning. The paper thus contributes to the culture/agency subtheme of the HECU6 conference. The paper begins by providing some background to the project before moving on to an exploration of the way Archer’s theoretical work was used to analyse data collected by project leaders.
- Full Text:
- Date Issued: 2012
The role of Hsp90/Hsp70 organising protein (Hop) in the Proliferation, Survival and Migration of Breast Cancer Cells.
- Authors: Willmer, Tarryn
- Date: 2012
- Subjects: Cancer -- Treatment , Heat shock proteins , Cancer cells , Breast -- Cancer
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4130 , http://hdl.handle.net/10962/d1015720
- Description: Hop (the Hsp90/Hsp70 organising protein) is a co-chaperone that acts as an adapter between the major molecular chaperones Hsp90 and Hsp70 during the cellular assembly of the Hsp90 complex. The Hsp90 complex regulates the stability and conformational maturation of a range of important cellular proteins, many of which are deregulated in cancer. In this study, we hypothesised that Hop knockdown inhibits proliferation and migration of cancer cells. We characterised the expression of Hop in cell models of different cancerous status, and provided evidence that Hop was upregulated in tumour cells compared to normal cell counterparts. Using an RNA interference approach, a 60-90% knockdown of Hop was achieved for up to 144 hours in the MDA-MB-231 and Hs578T breast cancer cell lines. Hop knockdown resulted in downregulation of the Hsp90 client proteins, Akt and Stat3, as well as a change in the expression of other Hsp90 co-chaperones, p23, Cdc37 and Aha1, while no change in the levels of Hsp90 or Hsp70 was observed. Silencing of Hop impaired cell proliferation in Hs578T cells but an increase in proliferation in MDA-MB-231, suggesting that the role of Hop in cancer cell proliferation was dependent on type of cancer cell. Hop knockdown in Hs578T and MDA-MB- 231 cells did not lead to any significant changes in the half maximal inhibitory concentrations (IC50) of selected small molecule inhibitors (paclitaxel, geldanamycin and novobiocin) in these cell lines after 72 hours. Hop knockdown cells were however, more sensitive than control cells to the Hsp90 inhibitors geldanamycin and novobiocin at earlier time points and in the presence of the drug transporter inhibitor, verapamil. Hop knockdown caused a decrease in cell migration as measured by the wound healing assay in both Hs578T and MDA-MB-231 cells. Hop was present in purified pseudopodia fractions of migrating cells, and immunofluorescence analysis showed that Hop colocalised with actin at the leading edges of pseudopodia, points of adhesion and at intercellular junctions of cells that have been stimulated to migrate with the chemokine stromal derived factor-1. Hop was able to bind to actin in vitro using actin cosedimentation assays, and silencing of Hop dramatically reduced the capacity of Hs578T cells to form pseudopodia. These results establish a correlation between Hop and actin dynamics, pseudopodia formation and migration in the context of Hop silencing, and collectively suggest that Hop plays a role in cancer cell migration. This study presents experimental evidence for a promising alternative to targeting Hsp90 and Hsp70 chaperones, a novel drug target in cancer therapy.
- Full Text:
- Date Issued: 2012
- Authors: Willmer, Tarryn
- Date: 2012
- Subjects: Cancer -- Treatment , Heat shock proteins , Cancer cells , Breast -- Cancer
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4130 , http://hdl.handle.net/10962/d1015720
- Description: Hop (the Hsp90/Hsp70 organising protein) is a co-chaperone that acts as an adapter between the major molecular chaperones Hsp90 and Hsp70 during the cellular assembly of the Hsp90 complex. The Hsp90 complex regulates the stability and conformational maturation of a range of important cellular proteins, many of which are deregulated in cancer. In this study, we hypothesised that Hop knockdown inhibits proliferation and migration of cancer cells. We characterised the expression of Hop in cell models of different cancerous status, and provided evidence that Hop was upregulated in tumour cells compared to normal cell counterparts. Using an RNA interference approach, a 60-90% knockdown of Hop was achieved for up to 144 hours in the MDA-MB-231 and Hs578T breast cancer cell lines. Hop knockdown resulted in downregulation of the Hsp90 client proteins, Akt and Stat3, as well as a change in the expression of other Hsp90 co-chaperones, p23, Cdc37 and Aha1, while no change in the levels of Hsp90 or Hsp70 was observed. Silencing of Hop impaired cell proliferation in Hs578T cells but an increase in proliferation in MDA-MB-231, suggesting that the role of Hop in cancer cell proliferation was dependent on type of cancer cell. Hop knockdown in Hs578T and MDA-MB- 231 cells did not lead to any significant changes in the half maximal inhibitory concentrations (IC50) of selected small molecule inhibitors (paclitaxel, geldanamycin and novobiocin) in these cell lines after 72 hours. Hop knockdown cells were however, more sensitive than control cells to the Hsp90 inhibitors geldanamycin and novobiocin at earlier time points and in the presence of the drug transporter inhibitor, verapamil. Hop knockdown caused a decrease in cell migration as measured by the wound healing assay in both Hs578T and MDA-MB-231 cells. Hop was present in purified pseudopodia fractions of migrating cells, and immunofluorescence analysis showed that Hop colocalised with actin at the leading edges of pseudopodia, points of adhesion and at intercellular junctions of cells that have been stimulated to migrate with the chemokine stromal derived factor-1. Hop was able to bind to actin in vitro using actin cosedimentation assays, and silencing of Hop dramatically reduced the capacity of Hs578T cells to form pseudopodia. These results establish a correlation between Hop and actin dynamics, pseudopodia formation and migration in the context of Hop silencing, and collectively suggest that Hop plays a role in cancer cell migration. This study presents experimental evidence for a promising alternative to targeting Hsp90 and Hsp70 chaperones, a novel drug target in cancer therapy.
- Full Text:
- Date Issued: 2012
The role of leadership in implementing service delivery initiatives: a case study of Buffalo City Municipality
- Authors: Mthembu, Bhekisisa Jacob
- Date: 2012
- Subjects: Local government -- South Africa -- Buffalo City Municipal services -- Management -- South Africa -- Buffalo City Public administration -- South Africa -- Buffalo City Political leadership -- South Africa -- Buffalo City Buffalo City (South Africa) -- Officials and employees Municipal officials and employees -- South Africa -- Buffalo City Municipal services -- South Africa -- Buffalo -- Citizen participation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:781 , http://hdl.handle.net/10962/d1003902
- Description: In terms of the South African Government Structure, Local Government is entrusted with the service delivery mandate. Furthermore, Local Government, being the closest sphere of government to the people, is expected to enhance service delivery to the communities within its jurisdiction. Local Government has for the past four years, undergone numerous transformation processes, ranging from Local Authorities, to Transitional Local Councils and to Municipalities. Having mentioned that, Buffalo City Metropolitan Municipality, in particular, has recently acquired metropolitan status, which requires another transformation protocol. At the same time this automatically raises the bar on the service delivery expectations by the communities. In general, Local Government has been extensively supported by the National and Provincial Governments to deliver superior services to communities. This has happened through numerous pieces of legislations such as the Municipal Structures Act 117 of 1998, the Municipal Systems Act 32 of 2000, the Municipal Finance Management Act 56 of 2003 and the Constitution of the Republic of South Africa, act 108 of 1996. In 1997, the South African Government introduced a White Paper on the Transformation of the Public Service. This was to re-emphasis on the performance enhancing role of both the political and administrative leadership in the implementation of service delivery mandates. The need was identified that communities require an assurance that their needs are taken care of by the leadership of the municipalities. It is therefore the role of leadership to ensure effective implementation of service delivery initiatives and to promote a culture of performance among the administrative officials of the municipality. The aim of this study is to critically investigate the role of leadership: A case study of Buffalo City Metropolitan Municipality (BCMM), with the view that BCMM is considered one of the high capacity municipalities within the Eastern Cape Province. During the literature review, it became evident that different people and scholars, dating back in the early 90’s, view leadership in different forms. In sourcing the information for this research, structured interviews were conducted with five Directors, five Executive Mayoral Councillors and five Ward Councillors. The interviews were an extensive consultation process which resulted in over 30 hours of engagement with research participants, with an average of 2 hours per structured interview. A four week period was allocated and effectively utilised for this exercise. The research provides recommendations for further research on other related components of the subject such as the intended role as compared to the current role fulfilled by both administrative and political leadership, and suggested solutions to the current problems in Municipalities, in order to ensure their sustainability within Local Government. The research findings identified the need for the leadership to take the leading role in service delivery initiatives in order to address the service delivery challenges in local government. Political leadership need to enhance the public participation process to ensure the community is on board regarding the progress of their respective projects and planning processes.
- Full Text:
- Date Issued: 2012
- Authors: Mthembu, Bhekisisa Jacob
- Date: 2012
- Subjects: Local government -- South Africa -- Buffalo City Municipal services -- Management -- South Africa -- Buffalo City Public administration -- South Africa -- Buffalo City Political leadership -- South Africa -- Buffalo City Buffalo City (South Africa) -- Officials and employees Municipal officials and employees -- South Africa -- Buffalo City Municipal services -- South Africa -- Buffalo -- Citizen participation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:781 , http://hdl.handle.net/10962/d1003902
- Description: In terms of the South African Government Structure, Local Government is entrusted with the service delivery mandate. Furthermore, Local Government, being the closest sphere of government to the people, is expected to enhance service delivery to the communities within its jurisdiction. Local Government has for the past four years, undergone numerous transformation processes, ranging from Local Authorities, to Transitional Local Councils and to Municipalities. Having mentioned that, Buffalo City Metropolitan Municipality, in particular, has recently acquired metropolitan status, which requires another transformation protocol. At the same time this automatically raises the bar on the service delivery expectations by the communities. In general, Local Government has been extensively supported by the National and Provincial Governments to deliver superior services to communities. This has happened through numerous pieces of legislations such as the Municipal Structures Act 117 of 1998, the Municipal Systems Act 32 of 2000, the Municipal Finance Management Act 56 of 2003 and the Constitution of the Republic of South Africa, act 108 of 1996. In 1997, the South African Government introduced a White Paper on the Transformation of the Public Service. This was to re-emphasis on the performance enhancing role of both the political and administrative leadership in the implementation of service delivery mandates. The need was identified that communities require an assurance that their needs are taken care of by the leadership of the municipalities. It is therefore the role of leadership to ensure effective implementation of service delivery initiatives and to promote a culture of performance among the administrative officials of the municipality. The aim of this study is to critically investigate the role of leadership: A case study of Buffalo City Metropolitan Municipality (BCMM), with the view that BCMM is considered one of the high capacity municipalities within the Eastern Cape Province. During the literature review, it became evident that different people and scholars, dating back in the early 90’s, view leadership in different forms. In sourcing the information for this research, structured interviews were conducted with five Directors, five Executive Mayoral Councillors and five Ward Councillors. The interviews were an extensive consultation process which resulted in over 30 hours of engagement with research participants, with an average of 2 hours per structured interview. A four week period was allocated and effectively utilised for this exercise. The research provides recommendations for further research on other related components of the subject such as the intended role as compared to the current role fulfilled by both administrative and political leadership, and suggested solutions to the current problems in Municipalities, in order to ensure their sustainability within Local Government. The research findings identified the need for the leadership to take the leading role in service delivery initiatives in order to address the service delivery challenges in local government. Political leadership need to enhance the public participation process to ensure the community is on board regarding the progress of their respective projects and planning processes.
- Full Text:
- Date Issued: 2012
The solo piano music of Einojuhani Rautavaara
- Authors: Matambo, Lotta Eleonoora
- Date: 2012
- Subjects: Rautavaara, Einojuhani, 1928 -- Piano music -- Criticism and interpretation Piano music -- History and criticism
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2646 , http://hdl.handle.net/10962/d1002311
- Description: Einojuhani Rautavaara's oeuvre is characterised by four distinctive creative periods, each demonstrating a remarkable variety of compositional idioms and styles. His application of multifaceted elements, often within a single work leading to notions of postmodernism, is derived from multifarious sources, such as (Finnish) folklore, Orthodox mysticism and a wide variety of standard twentieth century compositional techniques. Furthermore, Rautavaara regularly quotes from his own material, thus creating elements of auto-allusions within his oeuvre; a predisposition which forms an essential part of his compositional aesthetic. Analyses of eight piano works (1952-2007) provide a cross-section of Rautavaara's output which, together with a consideration of biographical factors and analytical focus on the intertextual elements of his writing, offers a rationale for determining the development of his musical identity. The analyses conclude that intertextual elements, which appear through a diverse array of expressive modes (such as mysticism, nationalism and constructivism) are an essential part of Rautavaara's eclectic compositional style and contribute to an understanding of the on-going development of his musical identity.
- Full Text:
- Date Issued: 2012
- Authors: Matambo, Lotta Eleonoora
- Date: 2012
- Subjects: Rautavaara, Einojuhani, 1928 -- Piano music -- Criticism and interpretation Piano music -- History and criticism
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2646 , http://hdl.handle.net/10962/d1002311
- Description: Einojuhani Rautavaara's oeuvre is characterised by four distinctive creative periods, each demonstrating a remarkable variety of compositional idioms and styles. His application of multifaceted elements, often within a single work leading to notions of postmodernism, is derived from multifarious sources, such as (Finnish) folklore, Orthodox mysticism and a wide variety of standard twentieth century compositional techniques. Furthermore, Rautavaara regularly quotes from his own material, thus creating elements of auto-allusions within his oeuvre; a predisposition which forms an essential part of his compositional aesthetic. Analyses of eight piano works (1952-2007) provide a cross-section of Rautavaara's output which, together with a consideration of biographical factors and analytical focus on the intertextual elements of his writing, offers a rationale for determining the development of his musical identity. The analyses conclude that intertextual elements, which appear through a diverse array of expressive modes (such as mysticism, nationalism and constructivism) are an essential part of Rautavaara's eclectic compositional style and contribute to an understanding of the on-going development of his musical identity.
- Full Text:
- Date Issued: 2012
The strategic alignment maturity of business and information technology at Volkswagen South Africa
- Authors: Naidoo, Lavendra
- Date: 2012
- Subjects: Industrial management -- South Africa Industrial management Business enterprises -- Information technology -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:789 , http://hdl.handle.net/10962/d1003910
- Description: During the past three decades Information Technology (IT) has been constantly evolving and has emerged into a significant component and enabler of most organisations strategy, to the point that modern day organisations are intrinsically dependent on IT (Peppard and Ward, 2004). Henderson and Venkatraman (1993) advocate that for an organisation to be successful in a dynamic and competitive business environment it is imperative that there is an effective and efficient IT strategy that enables the business strategy and processes. Volkswagen South Africa (VWSA)in 2007 launched its corporate strategy, 1:10:100 – 2010 At the end of this stated period 2010, VWSA achieved several of its objectives, namely surpassing its competitors in passenger vehicle sales volume, improving its customer satisfaction, achieving a higher level of local parts content per unit, developing its people and improving its infrastructure and processes.
- Full Text:
- Date Issued: 2012
- Authors: Naidoo, Lavendra
- Date: 2012
- Subjects: Industrial management -- South Africa Industrial management Business enterprises -- Information technology -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:789 , http://hdl.handle.net/10962/d1003910
- Description: During the past three decades Information Technology (IT) has been constantly evolving and has emerged into a significant component and enabler of most organisations strategy, to the point that modern day organisations are intrinsically dependent on IT (Peppard and Ward, 2004). Henderson and Venkatraman (1993) advocate that for an organisation to be successful in a dynamic and competitive business environment it is imperative that there is an effective and efficient IT strategy that enables the business strategy and processes. Volkswagen South Africa (VWSA)in 2007 launched its corporate strategy, 1:10:100 – 2010 At the end of this stated period 2010, VWSA achieved several of its objectives, namely surpassing its competitors in passenger vehicle sales volume, improving its customer satisfaction, achieving a higher level of local parts content per unit, developing its people and improving its infrastructure and processes.
- Full Text:
- Date Issued: 2012
The structural arrangements in local government and their role in promoting community participation in basic service delivery: a case study of Emalahleni and Intsika Yethu local municipalities in the Chris Hani District Municipality area
- Authors: Nqwemeshe, Nomvuyo
- Date: 2012
- Subjects: Local government -- South Africa -- Eastern Cape , Municipal services -- South Africa -- Eastern Cape -- Citizen participation , Water utilities -- South Africa -- Eastern Cape -- Citizen participation , Water-supply -- South Africa -- Eastern Cape -- Citizen participation , Community development -- South Africa -- Eastern Cape , Economic development projects -- Evaluation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3315 , http://hdl.handle.net/10962/d1003103
- Description: This study analyses the effectiveness of community participation in service delivery. The area of study, the Chris Ham District Municipality (CHDM), is a Water Services Authority, responsible for ensuring access to water services (water and sanitation) by all communities within its jurisdiction. There are eight local municipalities within the CHDM. The objective of this study is to determine whether systems are in place in local government to promote participation by communities in service delivery projects and whether these systems are being utilised efficiently by the role-players concerned. The role-players in this research are people who are involved in community development programmes of the municipality (municipal staff in the relevant departments of the municipalities under study, the social facilitators, civil society organisations, ward committees, ward councillors, traditional authorities as well as the representatives of communities (Project Steering Committees) who are beneficiaries of the projects under study). The projects that are under study were selected from a readily available list of CHDM capital projects that appear in the 2003/2004 financial year funding plan and are running. The findings of the study at both levels (local and district) show that the municipal environment is not conducive to promoting community participation. This is linked to factors such as the structural arrangements, whereby the offices relevant for promoting community participation are not fully occupied, which provided evidence that community participation is not prioritised. There is lack of coordination of programmes within the local government spheres as well within departments of the DM and strategies for community participation have been found to be non-effective. At project level lack of community participation is linked to the utilisation of ward committees as the only mechanism for community participation regardless of its un-equal and party biased representation. This study therefore concludes that although the systems to promote community participation are in place, they are not effective.
- Full Text:
- Date Issued: 2012
- Authors: Nqwemeshe, Nomvuyo
- Date: 2012
- Subjects: Local government -- South Africa -- Eastern Cape , Municipal services -- South Africa -- Eastern Cape -- Citizen participation , Water utilities -- South Africa -- Eastern Cape -- Citizen participation , Water-supply -- South Africa -- Eastern Cape -- Citizen participation , Community development -- South Africa -- Eastern Cape , Economic development projects -- Evaluation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3315 , http://hdl.handle.net/10962/d1003103
- Description: This study analyses the effectiveness of community participation in service delivery. The area of study, the Chris Ham District Municipality (CHDM), is a Water Services Authority, responsible for ensuring access to water services (water and sanitation) by all communities within its jurisdiction. There are eight local municipalities within the CHDM. The objective of this study is to determine whether systems are in place in local government to promote participation by communities in service delivery projects and whether these systems are being utilised efficiently by the role-players concerned. The role-players in this research are people who are involved in community development programmes of the municipality (municipal staff in the relevant departments of the municipalities under study, the social facilitators, civil society organisations, ward committees, ward councillors, traditional authorities as well as the representatives of communities (Project Steering Committees) who are beneficiaries of the projects under study). The projects that are under study were selected from a readily available list of CHDM capital projects that appear in the 2003/2004 financial year funding plan and are running. The findings of the study at both levels (local and district) show that the municipal environment is not conducive to promoting community participation. This is linked to factors such as the structural arrangements, whereby the offices relevant for promoting community participation are not fully occupied, which provided evidence that community participation is not prioritised. There is lack of coordination of programmes within the local government spheres as well within departments of the DM and strategies for community participation have been found to be non-effective. At project level lack of community participation is linked to the utilisation of ward committees as the only mechanism for community participation regardless of its un-equal and party biased representation. This study therefore concludes that although the systems to promote community participation are in place, they are not effective.
- Full Text:
- Date Issued: 2012
The symmetry group of a model of hyperbolic plane geometry and some associated invariant optimal control problems
- Authors: Henninger, Helen Clare
- Date: 2012
- Subjects: Geometry , Symmetry groups , Symmetry (Mathematics)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5432 , http://hdl.handle.net/10962/d1018232
- Description: In this thesis we study left-invariant control offine systems on the symmetry group of a. model of hyperbolic plane geometry, the matrix Lie group SO(1, 2)₀. We determine that there are 10 distinct classes of such control systems and for typical elements of two of these classes we provide solutions of the left-invariant optimal wntrol problem with quauratic costs. Under the identification of the Lie allgebra .so(l, 2) with Minkowski spacetime R¹̕'², we construct a controllabilility criterion for all left-invariant control affine systems on 50(1. 2)₀ which in the inhomogeneous case depends only on the presence or absence of an element in the image of the system's trace in R¹̕ ²which is identifiable using the inner product. For the solutions of both the optimal control problems, we provide explicit expressions in terms of Jacobi elliptic functions for the solutions of the reduced extremal equations and determine the nonlinear stability of the equilibrium points.
- Full Text:
- Date Issued: 2012
- Authors: Henninger, Helen Clare
- Date: 2012
- Subjects: Geometry , Symmetry groups , Symmetry (Mathematics)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5432 , http://hdl.handle.net/10962/d1018232
- Description: In this thesis we study left-invariant control offine systems on the symmetry group of a. model of hyperbolic plane geometry, the matrix Lie group SO(1, 2)₀. We determine that there are 10 distinct classes of such control systems and for typical elements of two of these classes we provide solutions of the left-invariant optimal wntrol problem with quauratic costs. Under the identification of the Lie allgebra .so(l, 2) with Minkowski spacetime R¹̕'², we construct a controllabilility criterion for all left-invariant control affine systems on 50(1. 2)₀ which in the inhomogeneous case depends only on the presence or absence of an element in the image of the system's trace in R¹̕ ²which is identifiable using the inner product. For the solutions of both the optimal control problems, we provide explicit expressions in terms of Jacobi elliptic functions for the solutions of the reduced extremal equations and determine the nonlinear stability of the equilibrium points.
- Full Text:
- Date Issued: 2012
The synthesis and breast cancer inhibitory activity of cinnamic acid analogues based on the halogenated monoterpene pharmacophore
- Authors: Chiwakata, Maynard Tendai
- Date: 2012
- Subjects: Halocarbons , Cancer -- Treatment , Breast -- Cancer -- Treatment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3866 , http://hdl.handle.net/10962/d1016129
- Description: Breast cancer is one of the leading causes of death, with mortality rate estimates of 465 000 deaths per annum. It is estimated that 1.3 million women are diagnosed with the disease each year especially in the developing countries. Current chemotherapy relies on the use of high doses of non-specific toxic agents that possess adverse side effects and compromise patient’s compliance and adherence to treatment. Paclitaxel, one of the common drugs used in breast cancer chemotherapy results in sensory and motor neuropathy, whilst hormonal therapy e.g. Herceptin causes severe cardiovascular, gastrointestinal and cutaneous side effects. There has been a demand in developing newer cancer agents that demonstrate selective cytoxicity with minimal effect on normal body tissue. Numerous studies have shown that marine organisms produce a wide range of halogenated compounds that possess cytotoxic properties, and hence can be a source of new drug hits or leads for cancer therapy. Halomon, a polyhalogenated monoterpene from Portieria hornemannii, displayed interesting activity against brain, renal and lung cancer tumours with selective/differential cytotoxicity. This inspired us to focus our project on halogenated monoterpenes isolated from the same Rhodophyta class as P. hornemannii but with particular attention to Plocamium species. Several metabolites have been isolated from P. cornutum, P. corallorhiza and P. suhrii that possess interesting cytotoxicities against a breast cancer cell line (MCF7) and an oesophageal cancer line (WHCO1). The aim of the project was therefore centred at isolating target compounds for preliminary structure-activity studies against a breast cancer cell line, and use this information to synthesize a series of analogues that are more stable than the natural products and yet as active using a fragment-based type approach to map out pharmacophoric elements. Five metabolites were isolated from P. cornutum and five from P. corallorhiza. Cell-based assays were conducted using an MTT assay kit against MCF7 and MDA-MB-231 breast cancer cell lines and (1E,3E,5S,6R)-1,5,6-trichloro-2-(dichloromethyl)-6-methylocta-1,3,7-triene, isolated from P. cornutum was the most active with IC50 values of 3.0 μM and 6.15 μM respectively. Introduction of a terminal aromatic ring to enhance stability, together with varying substituents (H, CH3, CF3, Br, CN, CHO, CHCl2) on position 7 of the molecule, gave rise to a series of cinnamate ester derivatives inspired by (1E,3E,5S,6R)-1,5,6-trichloro-2-(dichloromethyl)-6-methylocta-1,3,7-triene. The analogues were synthesized from their benzaldehyde precursors via Aldol condensation, esterification and Wittig reactions. Their carboxylic acid counterparts were synthesized by hydrolysis of the parent esters in an attempt to promote water solubilities of the analogues. Biological activity assays were then conducted with the cinnamate analogues against the MDA-MB-231 breast cancer cell line using an MTT assay kit. Ester derivatives with -CHO and -CHCl2 functionalities had IC50 values of 43.45 μM and 100.01 μM respectively whilst the other ester derivatives were inactive. It was concluded that either an aldehyde (-CHO) or gem-dichlorides (-CHCl2) is specifically required for cytotoxic activity to be observed. None of the carboxylic acids were active which could have been due to failure of the compounds to enter the breast cancer cells and reach the target site because of their polar nature. Compounds with -CHO and -CHCl2 functionalities were therefore selected for future SARs studies.
- Full Text:
- Date Issued: 2012
- Authors: Chiwakata, Maynard Tendai
- Date: 2012
- Subjects: Halocarbons , Cancer -- Treatment , Breast -- Cancer -- Treatment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3866 , http://hdl.handle.net/10962/d1016129
- Description: Breast cancer is one of the leading causes of death, with mortality rate estimates of 465 000 deaths per annum. It is estimated that 1.3 million women are diagnosed with the disease each year especially in the developing countries. Current chemotherapy relies on the use of high doses of non-specific toxic agents that possess adverse side effects and compromise patient’s compliance and adherence to treatment. Paclitaxel, one of the common drugs used in breast cancer chemotherapy results in sensory and motor neuropathy, whilst hormonal therapy e.g. Herceptin causes severe cardiovascular, gastrointestinal and cutaneous side effects. There has been a demand in developing newer cancer agents that demonstrate selective cytoxicity with minimal effect on normal body tissue. Numerous studies have shown that marine organisms produce a wide range of halogenated compounds that possess cytotoxic properties, and hence can be a source of new drug hits or leads for cancer therapy. Halomon, a polyhalogenated monoterpene from Portieria hornemannii, displayed interesting activity against brain, renal and lung cancer tumours with selective/differential cytotoxicity. This inspired us to focus our project on halogenated monoterpenes isolated from the same Rhodophyta class as P. hornemannii but with particular attention to Plocamium species. Several metabolites have been isolated from P. cornutum, P. corallorhiza and P. suhrii that possess interesting cytotoxicities against a breast cancer cell line (MCF7) and an oesophageal cancer line (WHCO1). The aim of the project was therefore centred at isolating target compounds for preliminary structure-activity studies against a breast cancer cell line, and use this information to synthesize a series of analogues that are more stable than the natural products and yet as active using a fragment-based type approach to map out pharmacophoric elements. Five metabolites were isolated from P. cornutum and five from P. corallorhiza. Cell-based assays were conducted using an MTT assay kit against MCF7 and MDA-MB-231 breast cancer cell lines and (1E,3E,5S,6R)-1,5,6-trichloro-2-(dichloromethyl)-6-methylocta-1,3,7-triene, isolated from P. cornutum was the most active with IC50 values of 3.0 μM and 6.15 μM respectively. Introduction of a terminal aromatic ring to enhance stability, together with varying substituents (H, CH3, CF3, Br, CN, CHO, CHCl2) on position 7 of the molecule, gave rise to a series of cinnamate ester derivatives inspired by (1E,3E,5S,6R)-1,5,6-trichloro-2-(dichloromethyl)-6-methylocta-1,3,7-triene. The analogues were synthesized from their benzaldehyde precursors via Aldol condensation, esterification and Wittig reactions. Their carboxylic acid counterparts were synthesized by hydrolysis of the parent esters in an attempt to promote water solubilities of the analogues. Biological activity assays were then conducted with the cinnamate analogues against the MDA-MB-231 breast cancer cell line using an MTT assay kit. Ester derivatives with -CHO and -CHCl2 functionalities had IC50 values of 43.45 μM and 100.01 μM respectively whilst the other ester derivatives were inactive. It was concluded that either an aldehyde (-CHO) or gem-dichlorides (-CHCl2) is specifically required for cytotoxic activity to be observed. None of the carboxylic acids were active which could have been due to failure of the compounds to enter the breast cancer cells and reach the target site because of their polar nature. Compounds with -CHO and -CHCl2 functionalities were therefore selected for future SARs studies.
- Full Text:
- Date Issued: 2012
The synthesis of fructooligosaccharides by the fructofuranosidase FopAp from Aspergillus niger
- Pindura, Mitchell Kingsley Chido
- Authors: Pindura, Mitchell Kingsley Chido
- Date: 2012
- Subjects: Aspergillus niger , Oligosaccharides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4158 , http://hdl.handle.net/10962/d1018267
- Description: Fructooligosaccharides (FOS) are short-chain fructans with a terminal glucose moiety and are found naturally in many plant species. Besides their wide use as an alternative sweetener in food and beverage industry, FOS have shown great potential as neutraceuticals against diabetes, colon cancer and bowel disease. The uses of FOS are dependent on the degree of polymerisation that they exhibit. β-fructofuranosidase (FFase) and fructosyltransferase (FTase) enzymes are capable of synthesing FOS from carbohydrate raw materials such as chicory and sugar beet. The aim of this study was to investigate the synthesis of FOS of a pre-defined chain length, from sucrose, by the enzyme FopAp; a β-fructofuranosidase from Aspergillus niger. ATCC 20611. The crude enzyme FopAp was successfully purified, with a yield of 78.20 %, by ammonium sulphate precipitation and anion exchange chromatography. Two protein fractions, named FA and FB were shown to exhibit FFase activity. SDS PAGE analysis revealed two proteins with molecular weights of 112 kDa and 78 kDa, which were identified as a FFase and a hydrolase. Temperature and pH optima of 20 ºC and 9, respectively, were observed for the transfructosylation activity in the FFase. The purified FFase exhibited a half life of 1.5 hrs under optimal conditions. Substrate kinetic studies indicated a high hydrolytic activity at low sucrose concentrations, with Vmax and Km of 1.25 μmol/ml/min and 3.28 mM, respectively. Analysis by response surface methodology identified temperature and pH to be significant factors for the production of kestose and nystose, at a 95 % level of confidence. These findings were confirmed by neural networks constructed to identify optimal conditions of FOS synthesis.FOS synthesis was found to be optimal between pH 6 and pH 9 at 25 ºC. The factor of reaction time was found to be insignificant within the selected experimental constraints, for both FOS species. The findings of this investigation are very important as the foundations of a commercially viable synthetic process for the production of FOS.
- Full Text:
- Date Issued: 2012
- Authors: Pindura, Mitchell Kingsley Chido
- Date: 2012
- Subjects: Aspergillus niger , Oligosaccharides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4158 , http://hdl.handle.net/10962/d1018267
- Description: Fructooligosaccharides (FOS) are short-chain fructans with a terminal glucose moiety and are found naturally in many plant species. Besides their wide use as an alternative sweetener in food and beverage industry, FOS have shown great potential as neutraceuticals against diabetes, colon cancer and bowel disease. The uses of FOS are dependent on the degree of polymerisation that they exhibit. β-fructofuranosidase (FFase) and fructosyltransferase (FTase) enzymes are capable of synthesing FOS from carbohydrate raw materials such as chicory and sugar beet. The aim of this study was to investigate the synthesis of FOS of a pre-defined chain length, from sucrose, by the enzyme FopAp; a β-fructofuranosidase from Aspergillus niger. ATCC 20611. The crude enzyme FopAp was successfully purified, with a yield of 78.20 %, by ammonium sulphate precipitation and anion exchange chromatography. Two protein fractions, named FA and FB were shown to exhibit FFase activity. SDS PAGE analysis revealed two proteins with molecular weights of 112 kDa and 78 kDa, which were identified as a FFase and a hydrolase. Temperature and pH optima of 20 ºC and 9, respectively, were observed for the transfructosylation activity in the FFase. The purified FFase exhibited a half life of 1.5 hrs under optimal conditions. Substrate kinetic studies indicated a high hydrolytic activity at low sucrose concentrations, with Vmax and Km of 1.25 μmol/ml/min and 3.28 mM, respectively. Analysis by response surface methodology identified temperature and pH to be significant factors for the production of kestose and nystose, at a 95 % level of confidence. These findings were confirmed by neural networks constructed to identify optimal conditions of FOS synthesis.FOS synthesis was found to be optimal between pH 6 and pH 9 at 25 ºC. The factor of reaction time was found to be insignificant within the selected experimental constraints, for both FOS species. The findings of this investigation are very important as the foundations of a commercially viable synthetic process for the production of FOS.
- Full Text:
- Date Issued: 2012