Bones of contention : contestations over human remains in the Eastern Cape
- Authors: Mkhize, Nomalanga
- Date: 2007
- Subjects: Dead -- Political aspects -- South Africa Human body -- Symbolic aspects Human remains (Archaeology) -- Repatriation Human remains (Archaeology) -- Repatriation -- South Africa -- Eastern Cape Xhosa (African people) -- Social life and customs Eastern Cape (South Africa) -- Social life and customs Eastern Cape (South Africa) -- History
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2597 , http://hdl.handle.net/10962/d1007665
- Description: This thesis examines three contestations involving human remains which have arisen in the Eastern Cape over the past fifteen years. It shows that the value or meaning attached to human remains is constructed through the socio-historical dynamics out of which these contestations arise. The meaning and value of human remains is neither inherent nor neutral. In Ndancama's case, the need for housing in Fingo Village led hundreds of poor residents to settle on the township's Old Cemetery in 1972. Basic material needs trumped concerns for those buried in the cemetery. When the post-apartheid municipality sought to provide sewerage and housing infrastructure for Ndancama in 2003, its development plans were constrained by new heritage legislation which protects historic cemeteries. Residents insisted that their infrastructural needs were of primary importance. In 1993, the unearthing of human remains at the Old Military Cemetery in King William's Town created a thirteen year long saga which was only resolved with the reburial of the remains in 2006. The presence of the remains proved problematic for a number of reasons. Local authorities failed to rebury the remains speedily. The burden to store them fell on the Kaffrarian Museum which came under fire because this was considered unethical in the postapartheid era. The identity of the remains became a bone of contention in 2006 when the new Amathole District Municipality concluded that the remains were those of victims who died in the 1856-57 Great Cattle Killing. The remains and their reburial became symbols of past injustice and present restoration of African heritage. The 1996 quest by 'Nicholas Gcaleka', a 'self-styled' chief and traditional healer, to search for King Hintsa's skull in the United Kingdom provoked unprecedented public engagement with the incomplete narrative on the fate of Hintsa's body. The power to represent history, and the methods through which historical truth is discovered were at the heart of the contestation. Elites such as the Xhosa Royal and the white scientific establishment were considered neither credible nor authoritative on this historical matter. Public support for Gcaleka revealed that many South Africans sought just recompense for colonial injustices.
- Full Text:
- Date Issued: 2007
- Authors: Mkhize, Nomalanga
- Date: 2007
- Subjects: Dead -- Political aspects -- South Africa Human body -- Symbolic aspects Human remains (Archaeology) -- Repatriation Human remains (Archaeology) -- Repatriation -- South Africa -- Eastern Cape Xhosa (African people) -- Social life and customs Eastern Cape (South Africa) -- Social life and customs Eastern Cape (South Africa) -- History
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2597 , http://hdl.handle.net/10962/d1007665
- Description: This thesis examines three contestations involving human remains which have arisen in the Eastern Cape over the past fifteen years. It shows that the value or meaning attached to human remains is constructed through the socio-historical dynamics out of which these contestations arise. The meaning and value of human remains is neither inherent nor neutral. In Ndancama's case, the need for housing in Fingo Village led hundreds of poor residents to settle on the township's Old Cemetery in 1972. Basic material needs trumped concerns for those buried in the cemetery. When the post-apartheid municipality sought to provide sewerage and housing infrastructure for Ndancama in 2003, its development plans were constrained by new heritage legislation which protects historic cemeteries. Residents insisted that their infrastructural needs were of primary importance. In 1993, the unearthing of human remains at the Old Military Cemetery in King William's Town created a thirteen year long saga which was only resolved with the reburial of the remains in 2006. The presence of the remains proved problematic for a number of reasons. Local authorities failed to rebury the remains speedily. The burden to store them fell on the Kaffrarian Museum which came under fire because this was considered unethical in the postapartheid era. The identity of the remains became a bone of contention in 2006 when the new Amathole District Municipality concluded that the remains were those of victims who died in the 1856-57 Great Cattle Killing. The remains and their reburial became symbols of past injustice and present restoration of African heritage. The 1996 quest by 'Nicholas Gcaleka', a 'self-styled' chief and traditional healer, to search for King Hintsa's skull in the United Kingdom provoked unprecedented public engagement with the incomplete narrative on the fate of Hintsa's body. The power to represent history, and the methods through which historical truth is discovered were at the heart of the contestation. Elites such as the Xhosa Royal and the white scientific establishment were considered neither credible nor authoritative on this historical matter. Public support for Gcaleka revealed that many South Africans sought just recompense for colonial injustices.
- Full Text:
- Date Issued: 2007
An investigation of the response of entities in the South African JSE ICT sector in 2005 to environmental sustainability reporting
- Authors: Rafferty, Kevin Lee
- Date: 2007
- Subjects: Information technology -- South Africa Communication in organizations -- South Africa Sustainable development -- South Africa Social responsibility of business -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:753 , http://hdl.handle.net/10962/d1003874
- Description: Pressure is on organisations the world over to report to their stakeholders, not only on their economic performance, but also on their environmental and social performance. In South Africa the King II code of corporate governance provides the guidance and impetus for this integrated “triple bottom line” sustainability reporting. The ICT sector in South Africa has been cited as lagging behind other sectors with regards to sustainability reporting, particularly in environmental sustainability reporting. Many ICT organisations would appear to be using their office and service based existence as reasons for having little or no impact on the environment. The study of the impacts of ICT on environmental sustainability in this research suggests that this is not necessarily the case. An assessment tool based on the internationally recognised Global Reporting Initiative Guidelines was developed in this research to investigate the level of environmental sustainability reporting in the South African ICT sector. The investigation showed the level of environmental sustainability reporting in the sector’s 2005 annual reports to be low. To get an indication of the level of reporting in more developed countries, a small sample of international ICT and service organisations was assessed using the tool, which showed significantly higher levels of environmental sustainability reporting. A set of ICT specific environmental sustainability performance indicators are proposed to enhance and encourage more significant levels of environmental sustainability reporting in South Africa.
- Full Text:
- Date Issued: 2007
- Authors: Rafferty, Kevin Lee
- Date: 2007
- Subjects: Information technology -- South Africa Communication in organizations -- South Africa Sustainable development -- South Africa Social responsibility of business -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:753 , http://hdl.handle.net/10962/d1003874
- Description: Pressure is on organisations the world over to report to their stakeholders, not only on their economic performance, but also on their environmental and social performance. In South Africa the King II code of corporate governance provides the guidance and impetus for this integrated “triple bottom line” sustainability reporting. The ICT sector in South Africa has been cited as lagging behind other sectors with regards to sustainability reporting, particularly in environmental sustainability reporting. Many ICT organisations would appear to be using their office and service based existence as reasons for having little or no impact on the environment. The study of the impacts of ICT on environmental sustainability in this research suggests that this is not necessarily the case. An assessment tool based on the internationally recognised Global Reporting Initiative Guidelines was developed in this research to investigate the level of environmental sustainability reporting in the South African ICT sector. The investigation showed the level of environmental sustainability reporting in the sector’s 2005 annual reports to be low. To get an indication of the level of reporting in more developed countries, a small sample of international ICT and service organisations was assessed using the tool, which showed significantly higher levels of environmental sustainability reporting. A set of ICT specific environmental sustainability performance indicators are proposed to enhance and encourage more significant levels of environmental sustainability reporting in South Africa.
- Full Text:
- Date Issued: 2007
Hermeneutics and memory in selected works by Willem Boshoff
- Authors: Tryon, Denzil Jordan
- Date: 2007
- Subjects: Boshoff, Willem, 1951- Hermeneutics Memory in art Art, Modern -- 20th century -- South Africa Installations (Art) -- South Africa
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2433 , http://hdl.handle.net/10962/d1004453
- Description: From Introduction: Willem Boshoff was born in Vereeniging, South Africa, in 1951. The son of a carpenter, Boshoff developed an early interest in art. Although never taught formally by his father, he nevertheless acquired a knowledge of the craft of carpentry, a skill which he continues to utilize in much of his art-making today. Boshoff studied at the Johannesburg College of Art, and obtained a Master's Diploma in Technology in Fine Art in 1984. He taught at that institution for twelve years, becoming a full-time art practitioner in 1996. He produced some significant works prior to and during the time of his teaching tenure, including his KykAfrikaans visual poetry in 1979-1980, Bangboek between 1977-1986, and the researching and writing of the Dictionary of Perplexing English in 1986 (ending in 1999). In this study I will discuss Willem Boshoff's careful employment of language and materials, througb which he propagates his "study of ignorance" (Williamson and Jamal 1996:148). I will investigate two major works by Boshoff, namely The Writing in the Sand and The Blind Alphabet in Chapters 1 and 2 respectively. Both of these installations are concerned fundamentally with the subversion of power relationships and elitism. As I will show, both works offer an opportunity to investigate their objectives in relation to discourses surrounding language and hermeneutics. My study includes a third chapter, in which I discuss my own work entitled The Bread of the Presence in relation to Boshoff's own methodologies. As will be demonstrated with particular reference to The Blind Alphabet and my own work, a discussion of memory proves to be of some relevance within this dialogue.
- Full Text:
- Date Issued: 2007
- Authors: Tryon, Denzil Jordan
- Date: 2007
- Subjects: Boshoff, Willem, 1951- Hermeneutics Memory in art Art, Modern -- 20th century -- South Africa Installations (Art) -- South Africa
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2433 , http://hdl.handle.net/10962/d1004453
- Description: From Introduction: Willem Boshoff was born in Vereeniging, South Africa, in 1951. The son of a carpenter, Boshoff developed an early interest in art. Although never taught formally by his father, he nevertheless acquired a knowledge of the craft of carpentry, a skill which he continues to utilize in much of his art-making today. Boshoff studied at the Johannesburg College of Art, and obtained a Master's Diploma in Technology in Fine Art in 1984. He taught at that institution for twelve years, becoming a full-time art practitioner in 1996. He produced some significant works prior to and during the time of his teaching tenure, including his KykAfrikaans visual poetry in 1979-1980, Bangboek between 1977-1986, and the researching and writing of the Dictionary of Perplexing English in 1986 (ending in 1999). In this study I will discuss Willem Boshoff's careful employment of language and materials, througb which he propagates his "study of ignorance" (Williamson and Jamal 1996:148). I will investigate two major works by Boshoff, namely The Writing in the Sand and The Blind Alphabet in Chapters 1 and 2 respectively. Both of these installations are concerned fundamentally with the subversion of power relationships and elitism. As I will show, both works offer an opportunity to investigate their objectives in relation to discourses surrounding language and hermeneutics. My study includes a third chapter, in which I discuss my own work entitled The Bread of the Presence in relation to Boshoff's own methodologies. As will be demonstrated with particular reference to The Blind Alphabet and my own work, a discussion of memory proves to be of some relevance within this dialogue.
- Full Text:
- Date Issued: 2007
Co-engaged learning : Xhosa women's narratives on traditional foods
- Authors: Jolly, Rachel
- Date: 2007
- Subjects: Xhosa (African people) -- Social life and customs -- South Africa -- Grahamstown Women, Xhosa -- South Africa -- Grahamstown Nutrition -- Study and teaching -- South Africa -- Grahamstown Ethnoscience -- Study and teaching -- South Africa -- Grahamstown AIDS (Disease) -- South Africa -- Grahamstown HIV infections -- South Africa -- Grahamstown Environmental education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1450 , http://hdl.handle.net/10962/d1003331
- Description: This interpretive case study examines Grahamstown East Xhosa women's narratives on the nutritional value of traditional foods. It reviews reflexive learning interactions apparent in the co-engaged narratives of food preparation practices. The research design incorporates methods of reflective co-engagement through which a small team of women were approached as 'co-researchers' in order to work together on shared, local knowledge capital and nutrition concerns. It draws on findings generated using a combination of semi-structured interviews, cooking demonstrations, videography, photographs and field observations as methods of data collection. Data were member-checked and reviewed in a rural context before the emerging evidence was analyzed using Bassey's (1999) analytical statements. Contextual factors influencing the study are high poverty, unemployment and HIV/AIDS prevalence where nutrition levels have been found to be low. The women making up the study have spent the majority of their lives in the peri-urban area of Grahamstown and in some cases, are more than one generation removed from rural living and its associated knowledge. The accompanying shift to modernization was found to influence the interplay between their narratives and practice. Indigenous Knowledge is often characterized by being situated in practice with the knowledge-holders often not 'knowing that they know.' This study concludes that it is not possible to assume that knowledge can always be consciously expressed, especially when that knowledge is embedded in practice. Related to this, co-engagement and diversity among the group gave rise to greater disequilibrium as well as making the knowledge more explicit and hence, available for reflection. The study suggests that through the process of co-engagement and deliberation around indigenous ways of knowing, agency and cultural identity appears to be enabled and strengthened.
- Full Text:
- Date Issued: 2007
- Authors: Jolly, Rachel
- Date: 2007
- Subjects: Xhosa (African people) -- Social life and customs -- South Africa -- Grahamstown Women, Xhosa -- South Africa -- Grahamstown Nutrition -- Study and teaching -- South Africa -- Grahamstown Ethnoscience -- Study and teaching -- South Africa -- Grahamstown AIDS (Disease) -- South Africa -- Grahamstown HIV infections -- South Africa -- Grahamstown Environmental education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1450 , http://hdl.handle.net/10962/d1003331
- Description: This interpretive case study examines Grahamstown East Xhosa women's narratives on the nutritional value of traditional foods. It reviews reflexive learning interactions apparent in the co-engaged narratives of food preparation practices. The research design incorporates methods of reflective co-engagement through which a small team of women were approached as 'co-researchers' in order to work together on shared, local knowledge capital and nutrition concerns. It draws on findings generated using a combination of semi-structured interviews, cooking demonstrations, videography, photographs and field observations as methods of data collection. Data were member-checked and reviewed in a rural context before the emerging evidence was analyzed using Bassey's (1999) analytical statements. Contextual factors influencing the study are high poverty, unemployment and HIV/AIDS prevalence where nutrition levels have been found to be low. The women making up the study have spent the majority of their lives in the peri-urban area of Grahamstown and in some cases, are more than one generation removed from rural living and its associated knowledge. The accompanying shift to modernization was found to influence the interplay between their narratives and practice. Indigenous Knowledge is often characterized by being situated in practice with the knowledge-holders often not 'knowing that they know.' This study concludes that it is not possible to assume that knowledge can always be consciously expressed, especially when that knowledge is embedded in practice. Related to this, co-engagement and diversity among the group gave rise to greater disequilibrium as well as making the knowledge more explicit and hence, available for reflection. The study suggests that through the process of co-engagement and deliberation around indigenous ways of knowing, agency and cultural identity appears to be enabled and strengthened.
- Full Text:
- Date Issued: 2007
An investigation into the deployment of IEEE 802.11 networks
- Janse van Rensburg, Johanna Hendrina
- Authors: Janse van Rensburg, Johanna Hendrina
- Date: 2007
- Subjects: Local area networks (Computer networks)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4596 , http://hdl.handle.net/10962/d1004839 , Local area networks (Computer networks)
- Description: Currently, the IEEE 802.11 standard is the leading technology in the Wireless Local Area Network (WLAN) market. It provides flexibility and mobility to users, which in turn, increase productivity. Opposed to traditional fixed Local Area Network (LAN) technologies, WLANs are easier to deploy and have lower installation costs. Unfortunately, there are problems inherent within the technology and standard that inhibits its performance. Technological problems can be attributed to the physical medium of a WLAN, the electromagnetic (EM) wave. Standards based problems include security issues and the MAC layer design. However the impact of these problems can be mitigated with proper planning and design of the WLAN. To do this, an understanding of WLAN issues and the use of WLAN software tools are necessary. This thesis discusses WLAN issues such as security and electromagnetic wave propagation and introduces software that can aid the planning, deployment and maintenance of a WLAN. Furthermore the planning, implementation and auditing phases of a WLAN lifecylce are discussed. The aim being to provide an understanding of the complexities involved to deploy and maintain a secure and reliable WLAN.
- Full Text:
- Date Issued: 2007
- Authors: Janse van Rensburg, Johanna Hendrina
- Date: 2007
- Subjects: Local area networks (Computer networks)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4596 , http://hdl.handle.net/10962/d1004839 , Local area networks (Computer networks)
- Description: Currently, the IEEE 802.11 standard is the leading technology in the Wireless Local Area Network (WLAN) market. It provides flexibility and mobility to users, which in turn, increase productivity. Opposed to traditional fixed Local Area Network (LAN) technologies, WLANs are easier to deploy and have lower installation costs. Unfortunately, there are problems inherent within the technology and standard that inhibits its performance. Technological problems can be attributed to the physical medium of a WLAN, the electromagnetic (EM) wave. Standards based problems include security issues and the MAC layer design. However the impact of these problems can be mitigated with proper planning and design of the WLAN. To do this, an understanding of WLAN issues and the use of WLAN software tools are necessary. This thesis discusses WLAN issues such as security and electromagnetic wave propagation and introduces software that can aid the planning, deployment and maintenance of a WLAN. Furthermore the planning, implementation and auditing phases of a WLAN lifecylce are discussed. The aim being to provide an understanding of the complexities involved to deploy and maintain a secure and reliable WLAN.
- Full Text:
- Date Issued: 2007
Genesis of environmental education policy in Botswana: construction and interpretation
- Ketlhoilwe, Mphemelang Joseph
- Authors: Ketlhoilwe, Mphemelang Joseph
- Date: 2007
- Subjects: Environmental education -- Botswana Education and state -- Botswana
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1549 , http://hdl.handle.net/10962/d1003431
- Description: This study is based on the 1994 Revised National Policy on Education (Botswana Government, 1994) that introduced environmental education into the Botswana’s education system. The main goals of this study were to understand the genealogy of and to critically analyze governmentality associated with environmental education policy in Botswana. Drawing on a post-structural genealogical approach to the subject matter (following Foucault) global historical events and their influence on policy in Botswana, views on environmental education and interpretation, and power relations in environmental education policy discourses were investigated. An investigation was conducted through document analysis, interviews, focus group discussions and observations. The analysis revealed that power relations have historically transcended environmental education policy discourses from global, regional to national levels. The exercise of power through international bodies, and bilateral and multilateral agreements has impacted on Botswana enabling her to enact policies to address socio-ecological crises or regulating them to sustainably utilize natural resources. However, evidence has shown that although Botswana accepted and introduced environmental education, structures were not ready for its implementation and hence some contextual problems are experienced by teachers in schools. The Revised National Policy on Education (RNPE) was constructed through a consultative process, but the final decision on what goes into the policy text was decided from the top (i.e. by the Ministry of Education senior officials). It emerged from this study that Botswana has inconsistently adopted sustainability and conservation-protection discourses in environmental education policy. The mix of the two discourses shows continuity of the protectionist-conservationist discourses and emergence of the current sustainable use discourse, creating a complex discourse environment. The study also revealed that in including these primarily western scientific discourses, other discourses were marginalized or excluded, which revealed continuity with colonial education discourses. The findings also revealed variance in the understanding of environmental education. The majority of the teachers understood and normalised new knowledge in environmental education as Environmental Science or Science, and equated environmental management activities with environmental education. Teachers deployed new governmentalities and normalizing strategies by following the traditional conservation and science epistemological and pedagogical discourses. They exercised various self-governing strategies to respond to the RNPE requirement regarding environmental education. The findings highlight the need for re-conceptualization of environmental education at macro(at Ministry of Education) and micro level. There is a need to harmonize the variation in policy interpretations and clarification of the conservation/environmental education and sustainability discourses running parallel in schools or to work more explicitly with multiple discourses. It has also emerged that teacher support mechanisms need review to enhance policy implementation. The study recommends that further and explicit analysis of environmental education discourses is critical for shaping the future of environmental education policy development and interpretation within Botswana’s education system.
- Full Text:
- Date Issued: 2007
- Authors: Ketlhoilwe, Mphemelang Joseph
- Date: 2007
- Subjects: Environmental education -- Botswana Education and state -- Botswana
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1549 , http://hdl.handle.net/10962/d1003431
- Description: This study is based on the 1994 Revised National Policy on Education (Botswana Government, 1994) that introduced environmental education into the Botswana’s education system. The main goals of this study were to understand the genealogy of and to critically analyze governmentality associated with environmental education policy in Botswana. Drawing on a post-structural genealogical approach to the subject matter (following Foucault) global historical events and their influence on policy in Botswana, views on environmental education and interpretation, and power relations in environmental education policy discourses were investigated. An investigation was conducted through document analysis, interviews, focus group discussions and observations. The analysis revealed that power relations have historically transcended environmental education policy discourses from global, regional to national levels. The exercise of power through international bodies, and bilateral and multilateral agreements has impacted on Botswana enabling her to enact policies to address socio-ecological crises or regulating them to sustainably utilize natural resources. However, evidence has shown that although Botswana accepted and introduced environmental education, structures were not ready for its implementation and hence some contextual problems are experienced by teachers in schools. The Revised National Policy on Education (RNPE) was constructed through a consultative process, but the final decision on what goes into the policy text was decided from the top (i.e. by the Ministry of Education senior officials). It emerged from this study that Botswana has inconsistently adopted sustainability and conservation-protection discourses in environmental education policy. The mix of the two discourses shows continuity of the protectionist-conservationist discourses and emergence of the current sustainable use discourse, creating a complex discourse environment. The study also revealed that in including these primarily western scientific discourses, other discourses were marginalized or excluded, which revealed continuity with colonial education discourses. The findings also revealed variance in the understanding of environmental education. The majority of the teachers understood and normalised new knowledge in environmental education as Environmental Science or Science, and equated environmental management activities with environmental education. Teachers deployed new governmentalities and normalizing strategies by following the traditional conservation and science epistemological and pedagogical discourses. They exercised various self-governing strategies to respond to the RNPE requirement regarding environmental education. The findings highlight the need for re-conceptualization of environmental education at macro(at Ministry of Education) and micro level. There is a need to harmonize the variation in policy interpretations and clarification of the conservation/environmental education and sustainability discourses running parallel in schools or to work more explicitly with multiple discourses. It has also emerged that teacher support mechanisms need review to enhance policy implementation. The study recommends that further and explicit analysis of environmental education discourses is critical for shaping the future of environmental education policy development and interpretation within Botswana’s education system.
- Full Text:
- Date Issued: 2007
Combined and additive effects of assembly tasks and constrained body postures
- Authors: Skelton, Sarah Anne
- Date: 2007
- Subjects: Musculoskeletal system -- Diseases , Human engineering , Posture , Posture disorders , Work -- Physiological aspects , Occupational diseases , Manual work , Job stress
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5107 , http://hdl.handle.net/10962/d1005185 , Musculoskeletal system -- Diseases , Human engineering , Posture , Posture disorders , Work -- Physiological aspects , Occupational diseases , Manual work , Job stress
- Description: Despite extensive research into musculoskeletal disorders (MSDs) they continue to plague workers. Manual materials handling (MMH), in particular the concurrence of load manipulation and awkward body posture, has been identified as a key factor in the onset of MSDs. Only a few studies have looked at the interaction between manipulation tasks and working posture during assembly tasks and as a result their relationship has not been widely explored. Assessing the stresses resulting from individual task factors and body posture in isolation and adding them together may be too simplified to estimate an overall risk profile, since this does not take into account that there may be a non-linear interaction in strain responses when manipulation task and body posture interact. Therefore, the present study investigated biophysical, physiological and psychophysical responses to combined tasks, rather than individual tasks of body posture and manipulative tasks. The objective of the research was to establish the interactive effects of constrained body postures and manipulative tasks and to identify whether a cumulative or compensatory reaction occurs during this interaction. Nine conditions were assessed in a laboratory setting, which included combinations of three working postures (standing, sitting and stooping) and three assembly tasks (torque wrenching, precision and no task). Thirty-six subjects were required to complete all nine conditions, with each condition lasting ninety seconds. Muscle activity was recorded for seven muscles from the upper extremity, trunk and lower extremity regions and was complemented by physiological (heart rate, tidal volume, minute ventilation, oxygen consumption, energy expenditure and breathing frequency) and psychophysical (body discomfort) data. At the completion of all nine conditions subjects completed a retrospective psychophysical rating questionnaire pertaining to discomfort felt during the conditions. Responses obtained for the different task and posture combinations revealed compensatory reactions (additive > combined) for most of the conditions assessed for the biomechanical and physiological responses. In the majority of cases for muscle activity, no significant differences were found between the combined and the additive effects (p < 0.05), while for the physiological responses there were mostly significant differences observed. Psychophysical responses indicated that there was a significant difference overall between the additive and combined effects. The results of this study demonstrate that in order to identify risk areas, manipulation tasks and constrained working postures may be considered either in isolation and added together (additive) or as a combined task, since there were very few significant differences observed between these two effects. Further studies are required, however, to provide conclusive evidence.
- Full Text:
- Date Issued: 2007
- Authors: Skelton, Sarah Anne
- Date: 2007
- Subjects: Musculoskeletal system -- Diseases , Human engineering , Posture , Posture disorders , Work -- Physiological aspects , Occupational diseases , Manual work , Job stress
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5107 , http://hdl.handle.net/10962/d1005185 , Musculoskeletal system -- Diseases , Human engineering , Posture , Posture disorders , Work -- Physiological aspects , Occupational diseases , Manual work , Job stress
- Description: Despite extensive research into musculoskeletal disorders (MSDs) they continue to plague workers. Manual materials handling (MMH), in particular the concurrence of load manipulation and awkward body posture, has been identified as a key factor in the onset of MSDs. Only a few studies have looked at the interaction between manipulation tasks and working posture during assembly tasks and as a result their relationship has not been widely explored. Assessing the stresses resulting from individual task factors and body posture in isolation and adding them together may be too simplified to estimate an overall risk profile, since this does not take into account that there may be a non-linear interaction in strain responses when manipulation task and body posture interact. Therefore, the present study investigated biophysical, physiological and psychophysical responses to combined tasks, rather than individual tasks of body posture and manipulative tasks. The objective of the research was to establish the interactive effects of constrained body postures and manipulative tasks and to identify whether a cumulative or compensatory reaction occurs during this interaction. Nine conditions were assessed in a laboratory setting, which included combinations of three working postures (standing, sitting and stooping) and three assembly tasks (torque wrenching, precision and no task). Thirty-six subjects were required to complete all nine conditions, with each condition lasting ninety seconds. Muscle activity was recorded for seven muscles from the upper extremity, trunk and lower extremity regions and was complemented by physiological (heart rate, tidal volume, minute ventilation, oxygen consumption, energy expenditure and breathing frequency) and psychophysical (body discomfort) data. At the completion of all nine conditions subjects completed a retrospective psychophysical rating questionnaire pertaining to discomfort felt during the conditions. Responses obtained for the different task and posture combinations revealed compensatory reactions (additive > combined) for most of the conditions assessed for the biomechanical and physiological responses. In the majority of cases for muscle activity, no significant differences were found between the combined and the additive effects (p < 0.05), while for the physiological responses there were mostly significant differences observed. Psychophysical responses indicated that there was a significant difference overall between the additive and combined effects. The results of this study demonstrate that in order to identify risk areas, manipulation tasks and constrained working postures may be considered either in isolation and added together (additive) or as a combined task, since there were very few significant differences observed between these two effects. Further studies are required, however, to provide conclusive evidence.
- Full Text:
- Date Issued: 2007
Treatment of wine distillery wastewaters by high rate anaerobic digestion and submerged membrane systems
- Authors: Melamane, Xolisa Lorraine
- Date: 2007
- Subjects: Wine and wine making -- Waste disposal Sewage -- Purification -- Anaerobic treatment Membrane reactors Bioreactors
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3963 , http://hdl.handle.net/10962/d1004022
- Description: Experiences in treating wine distillery wastewaters (WDWs) contribute to the field of oenology as many oenologists are concerned with the selection, efficiency and economy of their wastewaters. Wine distillery wastewaters are strongly acidic, have high chemical oxygen demand (COD), high polyphenol content and are highly variable. Primary attention was focussed on sustainable biological treatment of raw wine distillery wastewater (RWDW) and fungally pre-treated wine distillery wastewater (FTWDW) by energy-efficient high rate anaerobic digestion (AD). This study also explored the development of a novel dual-stage anaerobic digestion ultrafiltration (ADUF) process, using a ceramic submerged membrane bioreactor (SMBR) in the treatment of both RWDW and FTWDW. The first stage was for the selection of microorganisms that were able to treat the toxic pollutants from WDWs. It was operated at a high feed-to-microorganism ratio. The second stage, a secondary digester, was operated like a typical membrane bioreactor at a low feed-to-microorganism ratio to sustain a stable efficient population for a long period. The characteristics of RWDW were as follows: pH 3.83, 15 000 mg/l soluble COD (CODs) and 5229 mg/l of phenols. After pre-treatment of RWDW with Trametes pubescens, starting parameters for FTWDW were as follows: pH 6.7, 7000 mg/l soluble COD (CODS) and 1440 mg/l of phenols. During operation of a high rate anaerobic digester for RWDW treatment, K2HPO4 was required for buffering the digester. Volatile fatty acid concentrations were <300 mg/l throughout the study, indicating degradation of organic acids present. Mean CODS removal efficiency for the 130 day study was 87 %, while the mean polyphenol removal efficiency was 85 %. Addition of 50 mg/l Fe3+ increased the removal efficiencies of CODS to 97 % and of polyphenols to 99 %. High removal efficiencies of CODS and polyphenols were attributed to the addition of macronutrients and micronutrients that caused pH stability and stimulated microbial activity. The CODS removal efficiency of high rate anaerobic digestion of FTWDW reached 99.5%. During FTWDW digestion, pH buffering was achieved using K2HPO4. A combination of a SMBR and a secondary digester was tested for the treatment of RWDW and FTWDW during a 30 day study. Results for RWDW showed that pH buffering was achieved by dosing the feed stream with CaCO3 and K2HPO4. Buffering proved to be significant for optimum performance of the system in removal of soluble CODS, and volatile fatty acids (VFAs). Different batches of RWDW used for feeding the reactor had variable compositions with respect to concentrations of nitrates, ammonium and total phenolic compounds. Ammonium accumulated in the secondary digester after 14 days of system operation, indicated the time required for the establishment of anaerobic conditions in the system. Dosing of the SMBR treating FTWDW with CaCO3 and K2HPO4 buffered the pH; iii this proved significant for optimum performance of the system in removal of CODS. The system eliminated an average of 86 (± 4) % of CODS present in the FTWDW. The residual CODS levels in the effluent were approximately 400 mg/l, significantly lower than the concentrations observed when treating RWDW, indicating that fungal pre-treatment might have provided additional nutrients for removal of recalcitrant components of the wastewater. The resulting effluent was rich in nitrates and phosphates and might be used as a fertiliser. Alternatively, a membrane process, such as reverse osmosis (RO) or nanofiltration (NF) could be applied to raise the water quality to meet the levels required for reuse. Biomass samples were obtained from the four treatment systems and population shifts characterization using phospholipids fatty acids (PLFA) and 16S rRNA analysis to provide an indication of limitations within the microbial population. The values of the concentrations of the individual PLFAs detected in the samples indicated that ten bacterial species were present, with the GC content of the 16S rRNA increasing from 1 to 10. Analysis of denaturing gradient gel electrophoresis DGGE data indicated that the composition of the archeal community changed the consortia used for both RWDW and FTWDW treatment. Changes in band intensities indicated the presence of different components of the archeal communities. The results were not conclusive in terms of species identity as cloning, sequencing and phylogenetic analyses were not performed, but they did indicate microbial population shifts and species diversity for high rate anaerobic digestion. The results also confirmed prevalence of relatively few species during operation of SMBRs for treatment of RWDW and FTWDW, which suggested that the microorganisms that survived were either tolerant of toxic components of RWDW and FTWDW or they were able to remove polyphenols.
- Full Text:
- Date Issued: 2007
- Authors: Melamane, Xolisa Lorraine
- Date: 2007
- Subjects: Wine and wine making -- Waste disposal Sewage -- Purification -- Anaerobic treatment Membrane reactors Bioreactors
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3963 , http://hdl.handle.net/10962/d1004022
- Description: Experiences in treating wine distillery wastewaters (WDWs) contribute to the field of oenology as many oenologists are concerned with the selection, efficiency and economy of their wastewaters. Wine distillery wastewaters are strongly acidic, have high chemical oxygen demand (COD), high polyphenol content and are highly variable. Primary attention was focussed on sustainable biological treatment of raw wine distillery wastewater (RWDW) and fungally pre-treated wine distillery wastewater (FTWDW) by energy-efficient high rate anaerobic digestion (AD). This study also explored the development of a novel dual-stage anaerobic digestion ultrafiltration (ADUF) process, using a ceramic submerged membrane bioreactor (SMBR) in the treatment of both RWDW and FTWDW. The first stage was for the selection of microorganisms that were able to treat the toxic pollutants from WDWs. It was operated at a high feed-to-microorganism ratio. The second stage, a secondary digester, was operated like a typical membrane bioreactor at a low feed-to-microorganism ratio to sustain a stable efficient population for a long period. The characteristics of RWDW were as follows: pH 3.83, 15 000 mg/l soluble COD (CODs) and 5229 mg/l of phenols. After pre-treatment of RWDW with Trametes pubescens, starting parameters for FTWDW were as follows: pH 6.7, 7000 mg/l soluble COD (CODS) and 1440 mg/l of phenols. During operation of a high rate anaerobic digester for RWDW treatment, K2HPO4 was required for buffering the digester. Volatile fatty acid concentrations were <300 mg/l throughout the study, indicating degradation of organic acids present. Mean CODS removal efficiency for the 130 day study was 87 %, while the mean polyphenol removal efficiency was 85 %. Addition of 50 mg/l Fe3+ increased the removal efficiencies of CODS to 97 % and of polyphenols to 99 %. High removal efficiencies of CODS and polyphenols were attributed to the addition of macronutrients and micronutrients that caused pH stability and stimulated microbial activity. The CODS removal efficiency of high rate anaerobic digestion of FTWDW reached 99.5%. During FTWDW digestion, pH buffering was achieved using K2HPO4. A combination of a SMBR and a secondary digester was tested for the treatment of RWDW and FTWDW during a 30 day study. Results for RWDW showed that pH buffering was achieved by dosing the feed stream with CaCO3 and K2HPO4. Buffering proved to be significant for optimum performance of the system in removal of soluble CODS, and volatile fatty acids (VFAs). Different batches of RWDW used for feeding the reactor had variable compositions with respect to concentrations of nitrates, ammonium and total phenolic compounds. Ammonium accumulated in the secondary digester after 14 days of system operation, indicated the time required for the establishment of anaerobic conditions in the system. Dosing of the SMBR treating FTWDW with CaCO3 and K2HPO4 buffered the pH; iii this proved significant for optimum performance of the system in removal of CODS. The system eliminated an average of 86 (± 4) % of CODS present in the FTWDW. The residual CODS levels in the effluent were approximately 400 mg/l, significantly lower than the concentrations observed when treating RWDW, indicating that fungal pre-treatment might have provided additional nutrients for removal of recalcitrant components of the wastewater. The resulting effluent was rich in nitrates and phosphates and might be used as a fertiliser. Alternatively, a membrane process, such as reverse osmosis (RO) or nanofiltration (NF) could be applied to raise the water quality to meet the levels required for reuse. Biomass samples were obtained from the four treatment systems and population shifts characterization using phospholipids fatty acids (PLFA) and 16S rRNA analysis to provide an indication of limitations within the microbial population. The values of the concentrations of the individual PLFAs detected in the samples indicated that ten bacterial species were present, with the GC content of the 16S rRNA increasing from 1 to 10. Analysis of denaturing gradient gel electrophoresis DGGE data indicated that the composition of the archeal community changed the consortia used for both RWDW and FTWDW treatment. Changes in band intensities indicated the presence of different components of the archeal communities. The results were not conclusive in terms of species identity as cloning, sequencing and phylogenetic analyses were not performed, but they did indicate microbial population shifts and species diversity for high rate anaerobic digestion. The results also confirmed prevalence of relatively few species during operation of SMBRs for treatment of RWDW and FTWDW, which suggested that the microorganisms that survived were either tolerant of toxic components of RWDW and FTWDW or they were able to remove polyphenols.
- Full Text:
- Date Issued: 2007
Karen Horney : a psychobiographical study
- Authors: Green, Sarah-Jane
- Date: 2007
- Subjects: Horney, Karen, 1885-1952 Women psychologists Levinson, Daniel J., d.1994 Levinson, Daniel J., d.1994 -- The seasons of a woman's life
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3186 , http://hdl.handle.net/10962/d1008374
- Description: This psychobiography on the life of Karen Horney is an exploratory-descriptive study that aims to explore and describe Horney's life structure development according to Daniel Levinson's (1996) theory of adult development. The method of research uses a qualitative single-case research design that studies her life over her entire lifespan and highlights the individual characteristics of Horney in a holistic manner within her socio-historical context. A purposive sampling procedure was used to select Karen Horney as the subject of the research and only published data was analyzed in the research. Multiple sources of data are used to obtain the information in this research, including an autobiography and three biographies written by three different authors. This data is organized according to the temporal sequence of her lifespan and the developmental periods and time frame of Levinson's theory. Horney's life is described and explored to highlight those areas of her life that conform to the developmental theory and those aspects of her life that are not included in the theoretical constructs of Levinson 's theory. By exploring the significant relationships that Horney developed throughout her life with family, friends, work colleagues, community and religious affiliations, and the important issues in her development, this study verifies Levinson's theory by corroborating his conceptualisation of adult development as a process of sequential stages divided into four main eras of development, linked by three periods of transition. A shortcoming of Levinson's theory relates to his omission of self-esteem issues and religious concerns as relevant factors experienced during the era of pre-adulthood and spiritual concerns during the era of late adulthood.
- Full Text:
- Date Issued: 2007
- Authors: Green, Sarah-Jane
- Date: 2007
- Subjects: Horney, Karen, 1885-1952 Women psychologists Levinson, Daniel J., d.1994 Levinson, Daniel J., d.1994 -- The seasons of a woman's life
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3186 , http://hdl.handle.net/10962/d1008374
- Description: This psychobiography on the life of Karen Horney is an exploratory-descriptive study that aims to explore and describe Horney's life structure development according to Daniel Levinson's (1996) theory of adult development. The method of research uses a qualitative single-case research design that studies her life over her entire lifespan and highlights the individual characteristics of Horney in a holistic manner within her socio-historical context. A purposive sampling procedure was used to select Karen Horney as the subject of the research and only published data was analyzed in the research. Multiple sources of data are used to obtain the information in this research, including an autobiography and three biographies written by three different authors. This data is organized according to the temporal sequence of her lifespan and the developmental periods and time frame of Levinson's theory. Horney's life is described and explored to highlight those areas of her life that conform to the developmental theory and those aspects of her life that are not included in the theoretical constructs of Levinson 's theory. By exploring the significant relationships that Horney developed throughout her life with family, friends, work colleagues, community and religious affiliations, and the important issues in her development, this study verifies Levinson's theory by corroborating his conceptualisation of adult development as a process of sequential stages divided into four main eras of development, linked by three periods of transition. A shortcoming of Levinson's theory relates to his omission of self-esteem issues and religious concerns as relevant factors experienced during the era of pre-adulthood and spiritual concerns during the era of late adulthood.
- Full Text:
- Date Issued: 2007
An investigation of the key mechanisms that promote whole school development in a secondary school pilot project context
- Authors: Westraad, Susan Fiona
- Date: 2007
- Subjects: Education -- South Africa Education, Secondary -- South Africa Education and state -- South Africa School improvement programs -- South Africa Educational change -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1414 , http://hdl.handle.net/10962/d1003291
- Description: Providing relevant and quality schooling for all South African learners is the paramount goal of the South African National Department of Education. South Africa 's historical and current socio-economic contexts provide many challenges for both the Department of Education and schools in this endeavour to provide quality teaching and learning. These challenges impact directly and indirectly on what happens in the classroom. Since 1994 a plethora of education and training policy has been introduced in South Africa to redress historical imbalances; to introduce a new education and training framework and approach; and to provide guidelines, principles and procedures for addressing some of the challenges that impact on schools. The National Whole School Evaluation Policy provides the legislative framework for the establishment of a quality assurance process in South African schools based on accountability and support. The subsequent Integrated Quality Management System attempts to provide a framework for integrating school evaluation and performance measurement. Policy frameworks are in place to guide quality assurance and school improvement, however, the reality of implementing this at a grass roots level is particularly challenging. The General Motors (GM) South Africa Foundation, a non-governmental development organisation, established by General Motors (GM) South Africa, commenced with the piloting the Learning Schools Initiative to investigate some of the challenges of whole school development and evaluation. This research documents the Learning Schools Initiative's intervention with the initial two pilot secondary schools situated in Port Elizabeth (Nelson Mandela Bay) over a four-year period. It reviews the relevant school reform and school development literature and adopts a critical realist evaluative research approach to investigate the key mechanisms that promote whole school development and change in this context. In keeping with this approach, the results of the research are analysed and discussed within a context-menchanism-outcome configuration that involves the identification of the key mechanisms that bring about desired outcome/s in a specific context. Seven key generative mechanisms are identified as critical at a school and classroom level (i) school culture, (ii) school structures, (iii) effective leadership and management, (iv) personal growth and meaning, (v) restoration of relationships, (vi) professional development of educators, and development of capacity to work together, and (vii) support and accountability. The need to structure school development interventions around the triggering of identified key mechanisms is also identified as an important overarching mechanism. Suggestions are made for further research required to facilitate a deeper understanding of how to bring about meaningful change that results in quality teaching and learning in South African schools.
- Full Text:
- Date Issued: 2007
- Authors: Westraad, Susan Fiona
- Date: 2007
- Subjects: Education -- South Africa Education, Secondary -- South Africa Education and state -- South Africa School improvement programs -- South Africa Educational change -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1414 , http://hdl.handle.net/10962/d1003291
- Description: Providing relevant and quality schooling for all South African learners is the paramount goal of the South African National Department of Education. South Africa 's historical and current socio-economic contexts provide many challenges for both the Department of Education and schools in this endeavour to provide quality teaching and learning. These challenges impact directly and indirectly on what happens in the classroom. Since 1994 a plethora of education and training policy has been introduced in South Africa to redress historical imbalances; to introduce a new education and training framework and approach; and to provide guidelines, principles and procedures for addressing some of the challenges that impact on schools. The National Whole School Evaluation Policy provides the legislative framework for the establishment of a quality assurance process in South African schools based on accountability and support. The subsequent Integrated Quality Management System attempts to provide a framework for integrating school evaluation and performance measurement. Policy frameworks are in place to guide quality assurance and school improvement, however, the reality of implementing this at a grass roots level is particularly challenging. The General Motors (GM) South Africa Foundation, a non-governmental development organisation, established by General Motors (GM) South Africa, commenced with the piloting the Learning Schools Initiative to investigate some of the challenges of whole school development and evaluation. This research documents the Learning Schools Initiative's intervention with the initial two pilot secondary schools situated in Port Elizabeth (Nelson Mandela Bay) over a four-year period. It reviews the relevant school reform and school development literature and adopts a critical realist evaluative research approach to investigate the key mechanisms that promote whole school development and change in this context. In keeping with this approach, the results of the research are analysed and discussed within a context-menchanism-outcome configuration that involves the identification of the key mechanisms that bring about desired outcome/s in a specific context. Seven key generative mechanisms are identified as critical at a school and classroom level (i) school culture, (ii) school structures, (iii) effective leadership and management, (iv) personal growth and meaning, (v) restoration of relationships, (vi) professional development of educators, and development of capacity to work together, and (vii) support and accountability. The need to structure school development interventions around the triggering of identified key mechanisms is also identified as an important overarching mechanism. Suggestions are made for further research required to facilitate a deeper understanding of how to bring about meaningful change that results in quality teaching and learning in South African schools.
- Full Text:
- Date Issued: 2007
Molecular characterisation of the chaperone properties of Plasmodium falciparum heat shock protein 70
- Authors: Shonhai, Addmore
- Date: 2007
- Subjects: Heat shock proteins Plasmodium falciparum Protein folding Proteins -- Purification Molecular chaperones Malaria -- Prevention
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3977 , http://hdl.handle.net/10962/d1004036
- Description: Heat shock protein 70 (called DnaK in prokaryotes) is one of the most prominent groups of chaperones whose role is to prevent and reverse protein misfolding. PfHsp70 is a heatinducible cytoplasm/nuclear localised Plasmodium falciparum Hsp70. PfHsp70 is thought to confer chaperone cytoprotection to P. falciparum during the development of malaria fever. The objective of this study was to examine the chaperone properties of PfHsp70 using a bioinformatics approach, coupled to in vivo and in vitro analysis. Structural motifs that qualify PfHsp70 as a typical Hsp70 chaperone were identified. Although PfHsp70 has a higher similarity to human Hsc70 than E. coli DnaK, in vivocomplementation assays showed that PfHsp70 was able to reverse the thermosensitivity of E. coli dnaK756 (a temperature sensitive strain whose DnaK is functionally compromised). Two residues (V401 and Q402) in the linker region of PfHsp70 that are critical for its in vivo function were identified. Constructs were generated that encoded the ATPase domain of PfHsp70 and the peptide binding domain of E. coli DnaK (to generate PfK chimera); and the ATPase domain of E. coli DnaK fused to the peptide binding domain of PfHsp70 (KPf). The two chimeras were tested for their ability to reverse the thermosensitivity of E. coli dnaK756 cells. Whilst KPf was able to reverse the thermosensitivity of the E. coli dnaK756 cells, PfK could not. Previously, PfHsp70 purification involved urea denaturation. Using a detergent, polyethylenimine (PEI), PfHsp70 was natively purified. Natively purified PfHsp70 had a basal ATPase activity approximately two times higher than the previously reported activity for the protein purified through urea denaturation. PfJ4, a type II Hsp40, could not stimulate the ATPase activity of PfHsp70 in vitro. Arch and hydrophobic pocket substitutions (A419Y, Y444A and V451F) were introduced in the PfHsp70 peptide binding domain. Similar substitutions were also introduced in the KPf chimera. PfHsp70-V451F (hydrophobic pocket mutant) had marginally compromised in vivo function. However, a similar mutation (V436F), introduced in KPf abrogated the in vivo function of this chimera. The arch and hydrophobic pocket derivatives of PfHsp70 exhibited marginally compromised in vivo function, whilst equivalent mutations in KPf did not affect its in vivo function. The ability of PfHsp70 and its arch/hydrophobic pocket mutants to suppress the heatinduced aggregation of malate dehydrogenase (MDH) in vitro was investigated. Whilst PfHsp70 arch mutants displayed marginal functional loss in vivo, data from in vitro studies revealed that their functional deficiencies were more severe. This is the first study in which an Hsp70 from a parasitic eukaryote was able to suppress the thermosensitivity of an E. coli DnaK mutant strain. Findings from the in vivo and in vitro assays conducted on PfHsp70 suggest that this protein plays a key role in the life-cycle of P. falciparum. Furthermore, this study raised insights that are pertinent to the current dogma on the Hsp70 mechanism of action.
- Full Text:
- Date Issued: 2007
- Authors: Shonhai, Addmore
- Date: 2007
- Subjects: Heat shock proteins Plasmodium falciparum Protein folding Proteins -- Purification Molecular chaperones Malaria -- Prevention
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3977 , http://hdl.handle.net/10962/d1004036
- Description: Heat shock protein 70 (called DnaK in prokaryotes) is one of the most prominent groups of chaperones whose role is to prevent and reverse protein misfolding. PfHsp70 is a heatinducible cytoplasm/nuclear localised Plasmodium falciparum Hsp70. PfHsp70 is thought to confer chaperone cytoprotection to P. falciparum during the development of malaria fever. The objective of this study was to examine the chaperone properties of PfHsp70 using a bioinformatics approach, coupled to in vivo and in vitro analysis. Structural motifs that qualify PfHsp70 as a typical Hsp70 chaperone were identified. Although PfHsp70 has a higher similarity to human Hsc70 than E. coli DnaK, in vivocomplementation assays showed that PfHsp70 was able to reverse the thermosensitivity of E. coli dnaK756 (a temperature sensitive strain whose DnaK is functionally compromised). Two residues (V401 and Q402) in the linker region of PfHsp70 that are critical for its in vivo function were identified. Constructs were generated that encoded the ATPase domain of PfHsp70 and the peptide binding domain of E. coli DnaK (to generate PfK chimera); and the ATPase domain of E. coli DnaK fused to the peptide binding domain of PfHsp70 (KPf). The two chimeras were tested for their ability to reverse the thermosensitivity of E. coli dnaK756 cells. Whilst KPf was able to reverse the thermosensitivity of the E. coli dnaK756 cells, PfK could not. Previously, PfHsp70 purification involved urea denaturation. Using a detergent, polyethylenimine (PEI), PfHsp70 was natively purified. Natively purified PfHsp70 had a basal ATPase activity approximately two times higher than the previously reported activity for the protein purified through urea denaturation. PfJ4, a type II Hsp40, could not stimulate the ATPase activity of PfHsp70 in vitro. Arch and hydrophobic pocket substitutions (A419Y, Y444A and V451F) were introduced in the PfHsp70 peptide binding domain. Similar substitutions were also introduced in the KPf chimera. PfHsp70-V451F (hydrophobic pocket mutant) had marginally compromised in vivo function. However, a similar mutation (V436F), introduced in KPf abrogated the in vivo function of this chimera. The arch and hydrophobic pocket derivatives of PfHsp70 exhibited marginally compromised in vivo function, whilst equivalent mutations in KPf did not affect its in vivo function. The ability of PfHsp70 and its arch/hydrophobic pocket mutants to suppress the heatinduced aggregation of malate dehydrogenase (MDH) in vitro was investigated. Whilst PfHsp70 arch mutants displayed marginal functional loss in vivo, data from in vitro studies revealed that their functional deficiencies were more severe. This is the first study in which an Hsp70 from a parasitic eukaryote was able to suppress the thermosensitivity of an E. coli DnaK mutant strain. Findings from the in vivo and in vitro assays conducted on PfHsp70 suggest that this protein plays a key role in the life-cycle of P. falciparum. Furthermore, this study raised insights that are pertinent to the current dogma on the Hsp70 mechanism of action.
- Full Text:
- Date Issued: 2007
Evaluation of fishway designs for use at the ebb and flow region of rivers in the Eastern Cape, South Africa
- Authors: Lewis, Hylton Varian
- Date: 2007
- Subjects: Fishways -- South Africa -- Eastern Cape , Fishways -- Design and construction , Aquatic ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5279 , http://hdl.handle.net/10962/d1005123 , Fishways -- South Africa -- Eastern Cape , Fishways -- Design and construction , Aquatic ecology -- South Africa -- Eastern Cape
- Description: Fishways are devices that are increasingly being used worldwide to assist aquatic biofauna to migrate through man-made barriers such as weirs and large-scale dams that are used for water storage, electricity generation etc. and have a negative impact on both the upstream and downstream movement of aquatic organisms. Fishways are usually low gradient channels with evenly placed chambers which allow such migrating aquatic species minimal stress on their passage over these barriers. Despite the existence of national and regional policies for their provision, their construction has often been inhibited through a lack of local assessment of the available designs, and use of ineffective international designs. As part of a larger national research programme, sponsored by the Water Research Commission, to develop a protocol for fishway design and implementation, this study sought to investigate the suitability of vertical slot and sloping baffle designs to assist the migrations of juvenile catadromic fish species in the ebb and flow region of rivers in the Eastern Cape, South Africa. These fishways were initially tested under controlled conditions at the Experimental Fish Farm at the Department of Ichthyology and Fisheries Science, Rhodes University using various fish species. Using the performance data thus collected they were then installed and monitored in the field for the catadromic Myxus capensis (freshwater mullet) and Monodactylus falciformis (cape moony) migrations during March and November of 2005 at the Kowie River ebb and flow weir. The laboratory tests showed that there was a significantly higher level of migration success in the vertical slot compared with the sloping baffle fishway under all conditions (F=82.157; p<0.001). There was, however, a slow decline in levels of success with increased discharge in the vertical slot fishway. This was in contrast to the sloping baffle design where success increased as discharge increased at a steep gradient (F=74.894; p<0.005). The level of success with the M. capensis was related to the size of the fish for both systems with success increasing from the small to the large fish (F=17.755; p<0.001). For the M. falciformis higher levels of success were found to occur in the vertical slot fishway compared to the sloping baffle fishway (F=11.792; p<0.00086), with no significant differences being found with an increase in discharge. Field data indicated similar trends with higher migration success using the vertical slot fishway. M. capensis were better able to negotiate both devices compared to the M. falciformis and overall levels of success were higher for both species in the field than under laboratory conditions where the migration urge may have declined.
- Full Text:
- Date Issued: 2007
- Authors: Lewis, Hylton Varian
- Date: 2007
- Subjects: Fishways -- South Africa -- Eastern Cape , Fishways -- Design and construction , Aquatic ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5279 , http://hdl.handle.net/10962/d1005123 , Fishways -- South Africa -- Eastern Cape , Fishways -- Design and construction , Aquatic ecology -- South Africa -- Eastern Cape
- Description: Fishways are devices that are increasingly being used worldwide to assist aquatic biofauna to migrate through man-made barriers such as weirs and large-scale dams that are used for water storage, electricity generation etc. and have a negative impact on both the upstream and downstream movement of aquatic organisms. Fishways are usually low gradient channels with evenly placed chambers which allow such migrating aquatic species minimal stress on their passage over these barriers. Despite the existence of national and regional policies for their provision, their construction has often been inhibited through a lack of local assessment of the available designs, and use of ineffective international designs. As part of a larger national research programme, sponsored by the Water Research Commission, to develop a protocol for fishway design and implementation, this study sought to investigate the suitability of vertical slot and sloping baffle designs to assist the migrations of juvenile catadromic fish species in the ebb and flow region of rivers in the Eastern Cape, South Africa. These fishways were initially tested under controlled conditions at the Experimental Fish Farm at the Department of Ichthyology and Fisheries Science, Rhodes University using various fish species. Using the performance data thus collected they were then installed and monitored in the field for the catadromic Myxus capensis (freshwater mullet) and Monodactylus falciformis (cape moony) migrations during March and November of 2005 at the Kowie River ebb and flow weir. The laboratory tests showed that there was a significantly higher level of migration success in the vertical slot compared with the sloping baffle fishway under all conditions (F=82.157; p<0.001). There was, however, a slow decline in levels of success with increased discharge in the vertical slot fishway. This was in contrast to the sloping baffle design where success increased as discharge increased at a steep gradient (F=74.894; p<0.005). The level of success with the M. capensis was related to the size of the fish for both systems with success increasing from the small to the large fish (F=17.755; p<0.001). For the M. falciformis higher levels of success were found to occur in the vertical slot fishway compared to the sloping baffle fishway (F=11.792; p<0.00086), with no significant differences being found with an increase in discharge. Field data indicated similar trends with higher migration success using the vertical slot fishway. M. capensis were better able to negotiate both devices compared to the M. falciformis and overall levels of success were higher for both species in the field than under laboratory conditions where the migration urge may have declined.
- Full Text:
- Date Issued: 2007
The role of achievement motivation on the interlanguage fossilization of middle-aged English-as-a-second-language learners
- Authors: Vujisic, Zoran
- Date: 2007
- Subjects: Second language acquisition Language and languages -- Study and teaching Fossilization (Linguistics) Interlanguage (Language learning) English language -- Study and teaching -- Foreign speakers Motivation in education
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2368 , http://hdl.handle.net/10962/d1003748
- Description: Second language acquisition (SLA) is seldom entirely successful with adult learners. It has been suggested that all second language (L2) learners, in the process of mastering a target language (TL), develop a linguistic system that is self-contained and different from both the learner's native language and the TL. This system is referred to as 'interlanguage' (lL). In the process of SLA, IL evolves into an ever-closer approximation of the TL, and ideally, a learner's IL should continue to advance until it becomes equivalent to the TL. However, it has been observed that somewhere in the L2 learning process, IL may reach one or more plateaus during which the development of the IL is delayed or arrested. A permanent cessation of progress toward the TL is referred to as 'fossilization'. Researchers in SLA agree that motivation is one of the key factors influencing language-learning success and studies suggest that some language learning motivation may be related to the need for achievement. The purpose of this research was to establish if adult ESL learners are aware of fossilization and, to examine if motivation, and more specifically achievement motivation, is a factor in IL fossilization. The participants in this study consisted of 15 ESL learners in Puerto Rico who had at least eight years of formal ESL training. The instrument used to gather information included a questionnaire to obtain demographical and qualifying data, an 'English Language Proficiency Evaluation' to determine levels of IL fossilization, a 'Measure of Achievement Motivation' to ascertain achievement motive, and individual and group interviews in order to ascertain perception(s) regarding the role of motivation on fossilization and perceptions regarding the barriers to achieving TL competency. The research demonstrated that there is a moderate to strong positive relationship between IL fossilization and achievement motivation, i.e., high achievement motive is correlated to TL competency and descending levels of achievement motive are correlated to ascending levels of IL fossilization. The findings have significant implications for both ESL learning and instruction, and suggest that not all IL fossilization may be permanent.
- Full Text:
- Date Issued: 2007
- Authors: Vujisic, Zoran
- Date: 2007
- Subjects: Second language acquisition Language and languages -- Study and teaching Fossilization (Linguistics) Interlanguage (Language learning) English language -- Study and teaching -- Foreign speakers Motivation in education
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2368 , http://hdl.handle.net/10962/d1003748
- Description: Second language acquisition (SLA) is seldom entirely successful with adult learners. It has been suggested that all second language (L2) learners, in the process of mastering a target language (TL), develop a linguistic system that is self-contained and different from both the learner's native language and the TL. This system is referred to as 'interlanguage' (lL). In the process of SLA, IL evolves into an ever-closer approximation of the TL, and ideally, a learner's IL should continue to advance until it becomes equivalent to the TL. However, it has been observed that somewhere in the L2 learning process, IL may reach one or more plateaus during which the development of the IL is delayed or arrested. A permanent cessation of progress toward the TL is referred to as 'fossilization'. Researchers in SLA agree that motivation is one of the key factors influencing language-learning success and studies suggest that some language learning motivation may be related to the need for achievement. The purpose of this research was to establish if adult ESL learners are aware of fossilization and, to examine if motivation, and more specifically achievement motivation, is a factor in IL fossilization. The participants in this study consisted of 15 ESL learners in Puerto Rico who had at least eight years of formal ESL training. The instrument used to gather information included a questionnaire to obtain demographical and qualifying data, an 'English Language Proficiency Evaluation' to determine levels of IL fossilization, a 'Measure of Achievement Motivation' to ascertain achievement motive, and individual and group interviews in order to ascertain perception(s) regarding the role of motivation on fossilization and perceptions regarding the barriers to achieving TL competency. The research demonstrated that there is a moderate to strong positive relationship between IL fossilization and achievement motivation, i.e., high achievement motive is correlated to TL competency and descending levels of achievement motive are correlated to ascending levels of IL fossilization. The findings have significant implications for both ESL learning and instruction, and suggest that not all IL fossilization may be permanent.
- Full Text:
- Date Issued: 2007
Occult forces -- lived identities: witchcraft, spirit possession and cosmology amongst the Mayeyi of Namibia's Caprivi Strip
- Authors: Von Maltitz, Emil Arthur
- Date: 2007
- Subjects: Yeye (African people) , Yeye (African people) -- Namibia -- History , Occultism -- Namibia , Witchcraft -- Namibia , Spirit possession -- Namibia , Cosmology
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2121 , http://hdl.handle.net/10962/d1013279
- Description: Around Africa there seems to be an increasing disillusion with 'development', seen under the rubric of teleological 'progress', which is touted by post-colonial governments as being the cure for Africa's ailments and woes. Numerous authors have pointed out that this local disillusion, and the attempt to manage the inequities that arise through development and modernity, can be seen to be understood and acted upon by local peoples through the idiom of witchcraft beliefs and fears (see Geschiere & Fisiy 2001; Geschiere 1997; Nyamnjoh 2001; Comaroff & Comaroff 1993; Ashforth 2005) and spirit possession nanatives (see Luig 1999; Gezon 1999), or more simply, occult beliefs and praxis (Moore & Sanders 2001). The majority of the Mayeyi of Namibia's Eastern Caprivi perceive that development is the only way their regiOn and people can survive and succeed in a modernising world. At ~he same time there is also a seeming reluctance to move towards perceiving witchcraft as a means of accumulation (contra Geschiere 1997). This notion of the 'witchcraft of wealth' is emerging, but for the most part witches are seen as the enemies of development, while spirit possession narratives speak to the desire for development and of the identity of the group vis-a-vis the rest of the world. The thesis presented argues that, although modernity orientated analyses enable occult belief to be used as a lens through which to 1..mderstand 'modernity's malcontents' (Comaroff & Comaroff 1993), they can only go so far in explaining the intricacies of witchcraft and spirit possession beliefs themselves. The dissertation argues that one should return to the analysis of the cosmological underpinnings of witchcraft belief and spirit possession, taken together as complementary phenomena, in seeking to understand the domain of the occult. By doing so the thesis argues that a more comprehensive anthropological understanding is obtained of occult belief and practice, the ways in which the domain of the occult is constituted and the ways in which it is a reflection or commentary on a changing world.
- Full Text:
- Date Issued: 2007
- Authors: Von Maltitz, Emil Arthur
- Date: 2007
- Subjects: Yeye (African people) , Yeye (African people) -- Namibia -- History , Occultism -- Namibia , Witchcraft -- Namibia , Spirit possession -- Namibia , Cosmology
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2121 , http://hdl.handle.net/10962/d1013279
- Description: Around Africa there seems to be an increasing disillusion with 'development', seen under the rubric of teleological 'progress', which is touted by post-colonial governments as being the cure for Africa's ailments and woes. Numerous authors have pointed out that this local disillusion, and the attempt to manage the inequities that arise through development and modernity, can be seen to be understood and acted upon by local peoples through the idiom of witchcraft beliefs and fears (see Geschiere & Fisiy 2001; Geschiere 1997; Nyamnjoh 2001; Comaroff & Comaroff 1993; Ashforth 2005) and spirit possession nanatives (see Luig 1999; Gezon 1999), or more simply, occult beliefs and praxis (Moore & Sanders 2001). The majority of the Mayeyi of Namibia's Eastern Caprivi perceive that development is the only way their regiOn and people can survive and succeed in a modernising world. At ~he same time there is also a seeming reluctance to move towards perceiving witchcraft as a means of accumulation (contra Geschiere 1997). This notion of the 'witchcraft of wealth' is emerging, but for the most part witches are seen as the enemies of development, while spirit possession narratives speak to the desire for development and of the identity of the group vis-a-vis the rest of the world. The thesis presented argues that, although modernity orientated analyses enable occult belief to be used as a lens through which to 1..mderstand 'modernity's malcontents' (Comaroff & Comaroff 1993), they can only go so far in explaining the intricacies of witchcraft and spirit possession beliefs themselves. The dissertation argues that one should return to the analysis of the cosmological underpinnings of witchcraft belief and spirit possession, taken together as complementary phenomena, in seeking to understand the domain of the occult. By doing so the thesis argues that a more comprehensive anthropological understanding is obtained of occult belief and practice, the ways in which the domain of the occult is constituted and the ways in which it is a reflection or commentary on a changing world.
- Full Text:
- Date Issued: 2007
A preliminary examination of selected biological links between four Eastern Cape estuaries and the inshore marine environment
- Authors: Vorwerk, Paul D
- Date: 2007
- Subjects: Estuaries -- South Africa -- Eastern Cape Marine fishes -- South Africa -- Eastern Cape Marine ecology -- South Africa -- Eastern Cape Estuarine ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5747 , http://hdl.handle.net/10962/d1005434
- Description: The coastal transition zone (CTZ), which links the terrestrial and marine environments, has been identified as a region of high biological diversity and elevated production. Results of studies conducted in the northern hemisphere indicate that the links between estuaries and the adjacent marine environment is critical to ecological functioning within the CTZ. This study assessed the influence of selected estuaries with different hydrodynamic characteristics on the adjacent marine environment along the south-eastern coastline of southern Africa. Four estuaries were examined, including two permanently open systems, the fresh water deprived Kariega and fresh water dominated Great Fish, and two temporarily open/closed estuaries (TOCE), the Kasouga and East Kleinemonde. Results of the study indicated that outflow of estuarine water from the Great Fish Estuary contributed to a plume of less saline water being evident within the adjacent marine environment. The plume of water was associated with increased zooplankton biomass and particulate organic matter (POM) and chlorophyll-a concentrations. Adjacent to the Kariega Estuary, no evidence of fresh water outflow into the marine environment was observed. However, in the sea directly opposite the mouth of the estuary an increase in zooplankton abundance and biomass was evident. Results of numerical analyses indicated that the increase in zooplankton abundance observed adjacent to the mouth of both permanently open estuaries could not be attributed to the export of zooplankton from the estuary, but rather the accumulation of marine species within the region. The mechanisms responsible for this accumulation were not determined, but it was thought to be associated with increased food availability in the estuarine frontal zone. A similar, but less dramatic biological response was also observed in the marine environment adjacent to the two TOCEs. It is suggested that the increase in biological activity within these regions could be ascribed to seepage of estuarine or ground water through the sand bar that separates these estuaries from the sea. Results of stable carbon isotope analyses indicated that both the Great Fish and Kariega estuaries exported carbon to the nearshore marine environment. The area influenced by estuarine derived carbon was dependent on the volume of estuarine outflow to the marine environment. Adjacent to the fresh water dominated Great Fish Estuary, estuarine derived carbon was recorded up to 12km from the mouth, while adjacent to the fresh water deprived Kariega, estuarine derived carbon was only evident directly opposite the mouth. The recruitment of macrozooplankton (> 2cm) into the fresh water deprived Kariega Estuary was in the range recorded for other permanently open southern African estuaries with higher fresh water flow rates. This indicates that the mechanisms which allow estuarine dependent larvae to locate and enter estuaries are not related to fresh water inflow. In conclusion, this study has demonstrated that despite their small size relative to European and North American systems, South African permanently open and temporarily open/closed estuaries also influence biological activity within the adjacent nearshore marine environment.
- Full Text:
- Date Issued: 2007
- Authors: Vorwerk, Paul D
- Date: 2007
- Subjects: Estuaries -- South Africa -- Eastern Cape Marine fishes -- South Africa -- Eastern Cape Marine ecology -- South Africa -- Eastern Cape Estuarine ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5747 , http://hdl.handle.net/10962/d1005434
- Description: The coastal transition zone (CTZ), which links the terrestrial and marine environments, has been identified as a region of high biological diversity and elevated production. Results of studies conducted in the northern hemisphere indicate that the links between estuaries and the adjacent marine environment is critical to ecological functioning within the CTZ. This study assessed the influence of selected estuaries with different hydrodynamic characteristics on the adjacent marine environment along the south-eastern coastline of southern Africa. Four estuaries were examined, including two permanently open systems, the fresh water deprived Kariega and fresh water dominated Great Fish, and two temporarily open/closed estuaries (TOCE), the Kasouga and East Kleinemonde. Results of the study indicated that outflow of estuarine water from the Great Fish Estuary contributed to a plume of less saline water being evident within the adjacent marine environment. The plume of water was associated with increased zooplankton biomass and particulate organic matter (POM) and chlorophyll-a concentrations. Adjacent to the Kariega Estuary, no evidence of fresh water outflow into the marine environment was observed. However, in the sea directly opposite the mouth of the estuary an increase in zooplankton abundance and biomass was evident. Results of numerical analyses indicated that the increase in zooplankton abundance observed adjacent to the mouth of both permanently open estuaries could not be attributed to the export of zooplankton from the estuary, but rather the accumulation of marine species within the region. The mechanisms responsible for this accumulation were not determined, but it was thought to be associated with increased food availability in the estuarine frontal zone. A similar, but less dramatic biological response was also observed in the marine environment adjacent to the two TOCEs. It is suggested that the increase in biological activity within these regions could be ascribed to seepage of estuarine or ground water through the sand bar that separates these estuaries from the sea. Results of stable carbon isotope analyses indicated that both the Great Fish and Kariega estuaries exported carbon to the nearshore marine environment. The area influenced by estuarine derived carbon was dependent on the volume of estuarine outflow to the marine environment. Adjacent to the fresh water dominated Great Fish Estuary, estuarine derived carbon was recorded up to 12km from the mouth, while adjacent to the fresh water deprived Kariega, estuarine derived carbon was only evident directly opposite the mouth. The recruitment of macrozooplankton (> 2cm) into the fresh water deprived Kariega Estuary was in the range recorded for other permanently open southern African estuaries with higher fresh water flow rates. This indicates that the mechanisms which allow estuarine dependent larvae to locate and enter estuaries are not related to fresh water inflow. In conclusion, this study has demonstrated that despite their small size relative to European and North American systems, South African permanently open and temporarily open/closed estuaries also influence biological activity within the adjacent nearshore marine environment.
- Full Text:
- Date Issued: 2007
Particle precipitation effects on the South African ionosphere
- Authors: Sibanda, Patrick
- Date: 2007
- Subjects: Ionosphere -- South Africa , Precipitation (Chemistry) -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5481 , http://hdl.handle.net/10962/d1005267 , Ionosphere -- South Africa , Precipitation (Chemistry) -- South Africa
- Description: Particle precipitation involves the injection of energetic particles into the ionosphere which could increase the ionisation and conductivity of the upper atmosphere. The goal of this study was to examine the ionospheric response and changes due to particle precipitation in the region over South Africa, using a combination of groundbased and satellite instruments. Particle precipitation events were identified from satellite particle flux measurements of the Defence Meteorological Satellite Program (DMSP). Comprehensive studies were done on the events of 5 April, 2000 and 7 October, 2000. Analysis of the data from the satellite instruments indicates that no particle precipitation was observed over the South African region during these events and that it is unlikely to occur during other such events. To validate the data, methods and tools used in this study, precipitation in the South Atlantic anomaly (SAA) region is used. Satellite ion density measurements revealed that strong density enhancements occurred over the SAA region at satellite altitudes during the precipitation events, but this did not occur in the South African region. The measurements also revealed how the ionisation enhancements in the SAA region correlated with geomagnetic and solar activities. Particle precipitation and convective electric fields are two major magnetospheric energy sources to the upper atmosphere in the auroral and the SAA regions. These increase dramatically during geomagnetic storms and can disturb thermospheric circulation in the atmosphere and alter the rates of production and recombination of the ionised species. Ionosonde observations at Grahamstown, South Africa (33.30S, 26.50E), provided the data to build a picture of the response of the ionosphere over the South African region to particle precipitation during the precipitation events. This analysis showed that, within the confines of the available data, no direct connections between particle precipitation events and disturbances in the ionosphere over this region were revealed.
- Full Text:
- Date Issued: 2007
- Authors: Sibanda, Patrick
- Date: 2007
- Subjects: Ionosphere -- South Africa , Precipitation (Chemistry) -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5481 , http://hdl.handle.net/10962/d1005267 , Ionosphere -- South Africa , Precipitation (Chemistry) -- South Africa
- Description: Particle precipitation involves the injection of energetic particles into the ionosphere which could increase the ionisation and conductivity of the upper atmosphere. The goal of this study was to examine the ionospheric response and changes due to particle precipitation in the region over South Africa, using a combination of groundbased and satellite instruments. Particle precipitation events were identified from satellite particle flux measurements of the Defence Meteorological Satellite Program (DMSP). Comprehensive studies were done on the events of 5 April, 2000 and 7 October, 2000. Analysis of the data from the satellite instruments indicates that no particle precipitation was observed over the South African region during these events and that it is unlikely to occur during other such events. To validate the data, methods and tools used in this study, precipitation in the South Atlantic anomaly (SAA) region is used. Satellite ion density measurements revealed that strong density enhancements occurred over the SAA region at satellite altitudes during the precipitation events, but this did not occur in the South African region. The measurements also revealed how the ionisation enhancements in the SAA region correlated with geomagnetic and solar activities. Particle precipitation and convective electric fields are two major magnetospheric energy sources to the upper atmosphere in the auroral and the SAA regions. These increase dramatically during geomagnetic storms and can disturb thermospheric circulation in the atmosphere and alter the rates of production and recombination of the ionised species. Ionosonde observations at Grahamstown, South Africa (33.30S, 26.50E), provided the data to build a picture of the response of the ionosphere over the South African region to particle precipitation during the precipitation events. This analysis showed that, within the confines of the available data, no direct connections between particle precipitation events and disturbances in the ionosphere over this region were revealed.
- Full Text:
- Date Issued: 2007
A model for a context aware machine-based personal memory manager and its implementation using a visual programming environment
- Authors: Tsegaye, Melekam Asrat
- Date: 2007
- Subjects: Visual programming (Computer science) Memory management (Computer science) Memory -- Data processing
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4640 , http://hdl.handle.net/10962/d1006563
- Description: Memory is a part of cognition. It is essential for an individual to function normally in society. It encompasses an individual's lifetime experience, thus defining his identity. This thesis develops the concept of a machine-based personal memory manager which captures and manages an individual's day-to-day external memories. Rather than accumulating large amounts of data which has to be mined for useful memories, the machine-based memory manager automatically organizes memories as they are captured to enable their quick retrieval and use. The main functions of the machine-based memory manager envisioned in this thesis are the support and the augmentation of an individual's biological memory system. In the thesis, a model for a machine-based memory manager is developed. A visual programming environment, which can be used to build context aware applications as well as a proof-of-concept machine-based memory manager, is conceptualized and implemented. An experimental machine-based memory manager is implemented and evaluated. The model describes a machine-based memory manager which manages an individual's external memories by context. It addresses the management of external memories which accumulate over long periods of time by proposing a context aware file system which automatically organizes external memories by context. It describes how personal memory management can be facilitated by machine using six entities (life streams, memory producers, memory consumers, a memory manager, memory fragments and context descriptors) and the processes in which these entities participate (memory capture, memory encoding and decoding, memory decoding and retrieval). The visual programming environment represents a development tool which contains facilities that support context aware application programming. For example, it provides facilities which enable the definition and use of virtual sensors. It enables rapid programming with a focus on component re-use and dynamic composition of applications through a visual interface. The experimental machine-based memory manager serves as an example implementation of the machine-based memory manager which is described by the model developed in this thesis. The hardware used in its implementation consists of widely available components such as a camera, microphone and sub-notebook computer which are assembled in the form of a wearable computer. The software is constructed using the visual programming environment developed in this thesis. It contains multiple sensor drivers, context interpreters, a context aware file system as well as memory retrieval and presentation interfaces. The evaluation of the machine-based memory manager shows that it is possible to create a machine which monitors the states of an individual and his environment, and manages his external memories, thus supporting and augmenting his biological memory.
- Full Text:
- Date Issued: 2007
- Authors: Tsegaye, Melekam Asrat
- Date: 2007
- Subjects: Visual programming (Computer science) Memory management (Computer science) Memory -- Data processing
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4640 , http://hdl.handle.net/10962/d1006563
- Description: Memory is a part of cognition. It is essential for an individual to function normally in society. It encompasses an individual's lifetime experience, thus defining his identity. This thesis develops the concept of a machine-based personal memory manager which captures and manages an individual's day-to-day external memories. Rather than accumulating large amounts of data which has to be mined for useful memories, the machine-based memory manager automatically organizes memories as they are captured to enable their quick retrieval and use. The main functions of the machine-based memory manager envisioned in this thesis are the support and the augmentation of an individual's biological memory system. In the thesis, a model for a machine-based memory manager is developed. A visual programming environment, which can be used to build context aware applications as well as a proof-of-concept machine-based memory manager, is conceptualized and implemented. An experimental machine-based memory manager is implemented and evaluated. The model describes a machine-based memory manager which manages an individual's external memories by context. It addresses the management of external memories which accumulate over long periods of time by proposing a context aware file system which automatically organizes external memories by context. It describes how personal memory management can be facilitated by machine using six entities (life streams, memory producers, memory consumers, a memory manager, memory fragments and context descriptors) and the processes in which these entities participate (memory capture, memory encoding and decoding, memory decoding and retrieval). The visual programming environment represents a development tool which contains facilities that support context aware application programming. For example, it provides facilities which enable the definition and use of virtual sensors. It enables rapid programming with a focus on component re-use and dynamic composition of applications through a visual interface. The experimental machine-based memory manager serves as an example implementation of the machine-based memory manager which is described by the model developed in this thesis. The hardware used in its implementation consists of widely available components such as a camera, microphone and sub-notebook computer which are assembled in the form of a wearable computer. The software is constructed using the visual programming environment developed in this thesis. It contains multiple sensor drivers, context interpreters, a context aware file system as well as memory retrieval and presentation interfaces. The evaluation of the machine-based memory manager shows that it is possible to create a machine which monitors the states of an individual and his environment, and manages his external memories, thus supporting and augmenting his biological memory.
- Full Text:
- Date Issued: 2007
The artistic path to virtue
- Authors: Sher, Gavin
- Date: 2007
- Subjects: Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2732 , http://hdl.handle.net/10962/d1004370 , Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Description: Most people share a strong intuition that there is much to be learned from great literature and other forms of narrative art. This intuition is, however, philosophically contentious. Plato was the first to argue against the possibility of learning anything from narrative art, but he founded a tradition that persists to the present day. I will engage in this debate in order to examine the role narratives might be able to play in acquiring virtue on Aristotle's ethical account, as it is presented in Nicomachean Ethics. I will claim that narratives have so long seemed a problematic source of learning because philosophers have traditionally approached the issue in the wrong way. They have typically tried to show how we might acquire propositional knowledge through our engagement with art, but this approach has failed because of insoluble problems involved in satisfying the justification criterion. Fictions may be rescued from their problematic status by realising that what we truly get from them is, instead, a type of knowledge-how. I will argue that Aristotelian virtue is itself a kind of knowledge-how and so the type of learning that takes place in engaging with narratives has a role to play in its acquisition and exercise. Virtue depends on types of reasoning that are themselves kinds of knowledge-how and which are employed and improved in engaging with narrative art. These types of reasoning will be described as conceptual, emotional and imaginative understanding. I will show how each is important in relation to virtue and how each is a kind of knowledge-how that may be improved through exposure to narrative art.
- Full Text:
- Date Issued: 2007
- Authors: Sher, Gavin
- Date: 2007
- Subjects: Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2732 , http://hdl.handle.net/10962/d1004370 , Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Description: Most people share a strong intuition that there is much to be learned from great literature and other forms of narrative art. This intuition is, however, philosophically contentious. Plato was the first to argue against the possibility of learning anything from narrative art, but he founded a tradition that persists to the present day. I will engage in this debate in order to examine the role narratives might be able to play in acquiring virtue on Aristotle's ethical account, as it is presented in Nicomachean Ethics. I will claim that narratives have so long seemed a problematic source of learning because philosophers have traditionally approached the issue in the wrong way. They have typically tried to show how we might acquire propositional knowledge through our engagement with art, but this approach has failed because of insoluble problems involved in satisfying the justification criterion. Fictions may be rescued from their problematic status by realising that what we truly get from them is, instead, a type of knowledge-how. I will argue that Aristotelian virtue is itself a kind of knowledge-how and so the type of learning that takes place in engaging with narratives has a role to play in its acquisition and exercise. Virtue depends on types of reasoning that are themselves kinds of knowledge-how and which are employed and improved in engaging with narrative art. These types of reasoning will be described as conceptual, emotional and imaginative understanding. I will show how each is important in relation to virtue and how each is a kind of knowledge-how that may be improved through exposure to narrative art.
- Full Text:
- Date Issued: 2007
Transcending state-centrism: new regionalism and the future of Southern African regional integration
- Authors: Blaauw, Lesley
- Date: 2007
- Subjects: Southern African Development Community Southern African Customs Union Southern African Development Coordination Conference Regionalism -- Africa, Southern Africa, Southern -- Economic integration
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2761 , http://hdl.handle.net/10962/d1002971
- Description: This dissertation argues that in the 1990s and beyond, the character and functions of regions and regionalism have experienced a major transformation. This requires a reconceptualisation of regions and regionalism that transcends state-centrism. The argument here is that the definition of regions and regionalism needs to recognise that other actors also participate in the construction of regions and the practise of regionalism. Up to now, however, theories of integration incompletely deal with outcomes appropriate to developing countries, states and regions. In the context where people remain vulnerable to top-down forms of regionalism driven by the forces of globalisation, this calls for a new approach in the analytical study of regionalism in a transnational context. The contention is that new regionalism, and its variant, developmental regionalism pay attention to the role those organised civil society actors and those marginalised by both globalisation and regionalisation play in promoting regionalism in a transnational context. Historically, state-centric regionalism in southern Africa was not aimed at achieving developmental objectives. In the case of SACU, the argument is that South Africa used its economic strength in a hegemonial way. To counter-act apartheid South Africa’s economic hegemony, SADCC was formed. SADCC achieved limited success in the fields of infrastructural development and in attracting donor aid. The end of the Cold War and the downfall of apartheid compelled these organisations to recast their objectives and purpose. For SACU this meant changing from an organisation dominated by South Africa to a fully-fledged inter-state one. Disconcertedly, however, about the reforms undertook by SACU, is that the disposition of member states remain important in determining the content and scope of regionalism. SADC, on the other hand, has also not sufficiently reform itself to achieve the ambitious goals it set-out for itself. Moreover, while SADC has since its inception in 1992 set-out to involve non-state actors in its regional integration efforts, limited institutional reform in 2000 and beyond, and elites at the forefront of institutional restructuring make it difficult for non-state actors to contribute to sustainable regional integration. In conclusion, this dissertation maintains that sustainable regionalist orders are best built by recognising that beyond the geometry of state-sovereignty, civil society organisations with a regional focus and the ordinary people of the region also contribute to regioness and as such to the re-conceptualisation of regional community in southern Africa.
- Full Text:
- Date Issued: 2007
Transcending state-centrism: new regionalism and the future of Southern African regional integration
- Authors: Blaauw, Lesley
- Date: 2007
- Subjects: Southern African Development Community Southern African Customs Union Southern African Development Coordination Conference Regionalism -- Africa, Southern Africa, Southern -- Economic integration
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2761 , http://hdl.handle.net/10962/d1002971
- Description: This dissertation argues that in the 1990s and beyond, the character and functions of regions and regionalism have experienced a major transformation. This requires a reconceptualisation of regions and regionalism that transcends state-centrism. The argument here is that the definition of regions and regionalism needs to recognise that other actors also participate in the construction of regions and the practise of regionalism. Up to now, however, theories of integration incompletely deal with outcomes appropriate to developing countries, states and regions. In the context where people remain vulnerable to top-down forms of regionalism driven by the forces of globalisation, this calls for a new approach in the analytical study of regionalism in a transnational context. The contention is that new regionalism, and its variant, developmental regionalism pay attention to the role those organised civil society actors and those marginalised by both globalisation and regionalisation play in promoting regionalism in a transnational context. Historically, state-centric regionalism in southern Africa was not aimed at achieving developmental objectives. In the case of SACU, the argument is that South Africa used its economic strength in a hegemonial way. To counter-act apartheid South Africa’s economic hegemony, SADCC was formed. SADCC achieved limited success in the fields of infrastructural development and in attracting donor aid. The end of the Cold War and the downfall of apartheid compelled these organisations to recast their objectives and purpose. For SACU this meant changing from an organisation dominated by South Africa to a fully-fledged inter-state one. Disconcertedly, however, about the reforms undertook by SACU, is that the disposition of member states remain important in determining the content and scope of regionalism. SADC, on the other hand, has also not sufficiently reform itself to achieve the ambitious goals it set-out for itself. Moreover, while SADC has since its inception in 1992 set-out to involve non-state actors in its regional integration efforts, limited institutional reform in 2000 and beyond, and elites at the forefront of institutional restructuring make it difficult for non-state actors to contribute to sustainable regional integration. In conclusion, this dissertation maintains that sustainable regionalist orders are best built by recognising that beyond the geometry of state-sovereignty, civil society organisations with a regional focus and the ordinary people of the region also contribute to regioness and as such to the re-conceptualisation of regional community in southern Africa.
- Full Text:
- Date Issued: 2007
Development and in vitro evaluation of a clobetasol 17-propionate topical cream formulation
- Authors: Wa Kasongo, Kasongo
- Date: 2007
- Subjects: Adrenocortical hormones , Adrenocortical hormones -- Physiological effect , Drugs -- Testing , Drug development , Dermatopharmacology
- Language: English
- Type: Thesis , Masters , MPharm
- Identifier: vital:3799 , http://hdl.handle.net/10962/d1003277 , Adrenocortical hormones , Adrenocortical hormones -- Physiological effect , Drugs -- Testing , Drug development , Dermatopharmacology
- Description: One of the primary contributing factors to the escalating costs of health care is the high cost of innovator pharmaceutical products. As a consequence, health authorities in various countries and in particular in the developing world have identified generic prescribing and generic substitution as possible strategies to contain the escalating costs of health care provision. There is therefore a need for formulation scientists in developing countries to invest more time in the research and development of generic formulations. Clobetasol 17-propionate (CP) generic cream formulations containing 0.05% w/w of the drug were manufactured and characterized using in vitro testing. Formulation development studies were preceded by the development and validation of an RP-HPLC with UV detection for the quantitation and characterization of CP in innovator and generic cream formulations during formulation development and assessment studies. Furthermore the in vitro release ates of CP release from innovator and generic cream formulations were monitored using a validated in vitro release test method developed in these studies. The formulation of CP cream products was accomplished using a variety of commercially available mixed primary emulsifiers, such as Estol® 1474, Ritapro® 200, Emulcire® 61 WL and Gelot® 64. Successful formulations were selected based on their ability to remain physically stable immediately after manufacture and for 24 hours after storage at room temperature (22°C). Estol® 1474 was found to produce an unstable cream and was therefore not investigated further. The other three emulgents produced stable creams, but only the in vitro release profile of CP from a cream manufactured to contain Gelot® 64 was found to be statistically similar to that of the innovator formulation. Therefore the cream containing Gelot® 64 was selected as the most appropriate prototype generic cream formulation and was characterized in vitro in terms of CP content, viscosity, pH and in vitro release rate. Data generated from these studies were compared to those of the innovator product, Dermovate® cream, using statistical methods. The CP content, pH and in vitro release rate data of the CP formulation were similar to those of the innovator product, however the intrinsic viscosity of Dermovate® cream was almost three (3) times greater than the intrinsic viscosity of the test formulation developed using Gelot® 64. The CP cream formulation developed in these studies was stored for 4 weeks at 40 ± 2°C and 25 ± 5% RH in an incubator and the formulation was found to be stable. A formulation has been developed and assessed and found to be suitable for use as a topical semi-solid dosage form for CP.
- Full Text:
- Date Issued: 2007
- Authors: Wa Kasongo, Kasongo
- Date: 2007
- Subjects: Adrenocortical hormones , Adrenocortical hormones -- Physiological effect , Drugs -- Testing , Drug development , Dermatopharmacology
- Language: English
- Type: Thesis , Masters , MPharm
- Identifier: vital:3799 , http://hdl.handle.net/10962/d1003277 , Adrenocortical hormones , Adrenocortical hormones -- Physiological effect , Drugs -- Testing , Drug development , Dermatopharmacology
- Description: One of the primary contributing factors to the escalating costs of health care is the high cost of innovator pharmaceutical products. As a consequence, health authorities in various countries and in particular in the developing world have identified generic prescribing and generic substitution as possible strategies to contain the escalating costs of health care provision. There is therefore a need for formulation scientists in developing countries to invest more time in the research and development of generic formulations. Clobetasol 17-propionate (CP) generic cream formulations containing 0.05% w/w of the drug were manufactured and characterized using in vitro testing. Formulation development studies were preceded by the development and validation of an RP-HPLC with UV detection for the quantitation and characterization of CP in innovator and generic cream formulations during formulation development and assessment studies. Furthermore the in vitro release ates of CP release from innovator and generic cream formulations were monitored using a validated in vitro release test method developed in these studies. The formulation of CP cream products was accomplished using a variety of commercially available mixed primary emulsifiers, such as Estol® 1474, Ritapro® 200, Emulcire® 61 WL and Gelot® 64. Successful formulations were selected based on their ability to remain physically stable immediately after manufacture and for 24 hours after storage at room temperature (22°C). Estol® 1474 was found to produce an unstable cream and was therefore not investigated further. The other three emulgents produced stable creams, but only the in vitro release profile of CP from a cream manufactured to contain Gelot® 64 was found to be statistically similar to that of the innovator formulation. Therefore the cream containing Gelot® 64 was selected as the most appropriate prototype generic cream formulation and was characterized in vitro in terms of CP content, viscosity, pH and in vitro release rate. Data generated from these studies were compared to those of the innovator product, Dermovate® cream, using statistical methods. The CP content, pH and in vitro release rate data of the CP formulation were similar to those of the innovator product, however the intrinsic viscosity of Dermovate® cream was almost three (3) times greater than the intrinsic viscosity of the test formulation developed using Gelot® 64. The CP cream formulation developed in these studies was stored for 4 weeks at 40 ± 2°C and 25 ± 5% RH in an incubator and the formulation was found to be stable. A formulation has been developed and assessed and found to be suitable for use as a topical semi-solid dosage form for CP.
- Full Text:
- Date Issued: 2007