Emancipatory spaces in the post-colony : South Africa and the case for AbM and UPM
- Authors: Tselapedi, Thapelo
- Date: 2012
- Subjects: Local government -- South Africa -- Grahamstown Postcolonialism -- South Africa -- Grahamstown Apartheid -- South Africa Civil society -- South Africa -- Grahamstown Social movements -- South Africa -- Grahamstown South Africa -- Economic conditions -- 1991- South Africa -- Economic policy South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2839 , http://hdl.handle.net/10962/d1004451
- Description: This thesis is about the relationship between local government, grassroots organisations and the organisation of power resulting from the interaction of the two. Exploring this relationship this thesis investigates whether the actions of grassroots movements can bring local government in line with their developmental role as accorded to them by the Constitution. The assumption embedded in this question is that the current balance of power at the local level exists outside of the service of the historically disadvantaged. Following on from that, the thesis explores, through different modes of analysis, theoretical and historical, the policy and constitutional framework for local government, and then it unravels the context set by the political economy of South Africa. The aim is to make a significant attempt at understanding the possible implications of the interventions grassroots movements make in the public space. The thesis does this also by looking at the strengths and weaknesses of the strategies of the UDF to makes an assessment of the possible endurance of post-apartheid grassroots movements. Since civil society ‘suffers’ from nationalist politics, with its own corporatist institutions, the thesis searches deep within or arguably 'outside of civil society', subjecting AbM and UPM to academic critique, to see how movements embedded among the poor and carrying the political instrument of anger and marginalisation, can dislodge the power of capital. More importantly, the thesis situates the post-apartheid moment within postcolonial politics; navigating through the legacy of Colonialism of a Special Type (CSP), the thesis explores the limits and opportunities at the disposal of grassroots movements. From a different perspective, the thesis is an examination of the organisation and movement of power and the spaces within which power and ideas are contested. Drawing on the political and economic engagements, dubbed the Dar Es Salaam debates, in the 1970’s and 1980’s spurred on by Issa Shivji, the late Prof Dani Wadada Nabudere and Mahmood Mandani, the conclusions of this thesis develops these engagements, essentially making a case for the continued centrality of the post-apartheid state. However, the thesis also asserts the indubitable role that both grassroots movements and civil society need to play, not necessarily in the democratisation of the state, though that goes without saying, but in taking the post-colonial state on its own terms. Consequently, the thesis puts forward the idea that issue-based mobilisation does exactly this, and in the manner that acknowledges the state’s centrality and makes paramount the self-organisation (popular assemblies) of ordinary people in public affairs. The thesis categorically concludes that the centrality of the post-apartheid state and its progressive outlook (constitutional values) is contingent on organs of popular assemblies which need to take the state on its (progressive) terms.
- Full Text:
- Date Issued: 2012
- Authors: Tselapedi, Thapelo
- Date: 2012
- Subjects: Local government -- South Africa -- Grahamstown Postcolonialism -- South Africa -- Grahamstown Apartheid -- South Africa Civil society -- South Africa -- Grahamstown Social movements -- South Africa -- Grahamstown South Africa -- Economic conditions -- 1991- South Africa -- Economic policy South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2839 , http://hdl.handle.net/10962/d1004451
- Description: This thesis is about the relationship between local government, grassroots organisations and the organisation of power resulting from the interaction of the two. Exploring this relationship this thesis investigates whether the actions of grassroots movements can bring local government in line with their developmental role as accorded to them by the Constitution. The assumption embedded in this question is that the current balance of power at the local level exists outside of the service of the historically disadvantaged. Following on from that, the thesis explores, through different modes of analysis, theoretical and historical, the policy and constitutional framework for local government, and then it unravels the context set by the political economy of South Africa. The aim is to make a significant attempt at understanding the possible implications of the interventions grassroots movements make in the public space. The thesis does this also by looking at the strengths and weaknesses of the strategies of the UDF to makes an assessment of the possible endurance of post-apartheid grassroots movements. Since civil society ‘suffers’ from nationalist politics, with its own corporatist institutions, the thesis searches deep within or arguably 'outside of civil society', subjecting AbM and UPM to academic critique, to see how movements embedded among the poor and carrying the political instrument of anger and marginalisation, can dislodge the power of capital. More importantly, the thesis situates the post-apartheid moment within postcolonial politics; navigating through the legacy of Colonialism of a Special Type (CSP), the thesis explores the limits and opportunities at the disposal of grassroots movements. From a different perspective, the thesis is an examination of the organisation and movement of power and the spaces within which power and ideas are contested. Drawing on the political and economic engagements, dubbed the Dar Es Salaam debates, in the 1970’s and 1980’s spurred on by Issa Shivji, the late Prof Dani Wadada Nabudere and Mahmood Mandani, the conclusions of this thesis develops these engagements, essentially making a case for the continued centrality of the post-apartheid state. However, the thesis also asserts the indubitable role that both grassroots movements and civil society need to play, not necessarily in the democratisation of the state, though that goes without saying, but in taking the post-colonial state on its own terms. Consequently, the thesis puts forward the idea that issue-based mobilisation does exactly this, and in the manner that acknowledges the state’s centrality and makes paramount the self-organisation (popular assemblies) of ordinary people in public affairs. The thesis categorically concludes that the centrality of the post-apartheid state and its progressive outlook (constitutional values) is contingent on organs of popular assemblies which need to take the state on its (progressive) terms.
- Full Text:
- Date Issued: 2012
Experiences of operating room nurses in their work environment at a state hospital in Ethiopia
- Authors: Woldehawariat, Negat
- Date: 2012
- Subjects: Operating room nurses -- Ethiopia , Operating rooms -- Ethiopia , Work environment -- Ethiopia
- Language: English
- Type: Thesis , Masters , MCur
- Identifier: vital:10024 , http://hdl.handle.net/10948/d1008177 , Operating room nurses -- Ethiopia , Operating rooms -- Ethiopia , Work environment -- Ethiopia
- Description: Operating room nursing skills are some of the most demanding skills in the nursing profession. At the moment nurses trained in operating room technique are in very short supply in Ethiopia, due to the exodus of nurses to better working environments with more reasonable payment. This is especially noticeable in one of the state hospitals in Addis Ababa, Ethiopia, as emerged in conversations with the head nurse of the operating room in this hospital about the high turnover rate, as well as the high absenteeism rate amongst the nurses working in the operating room. Nurses working in the operating room also expressed unhappiness in their work environment which could cause them to look for other jobs or to be absent from duty. The nurses were facing numerous problems in their work environment such as work overload due to staff shortage, stress due to shortage of supplies because they are not able to do their job as much as the need requires. The researcher identified the need to explore the challenges that the operating room nurses are experiencing in their work environment. The researcher used the following questions to meet the research objectives: What are the experiences of the operating room nurses in their work environment?; What potential assistance would such nurses need to better cope with the problems they experience in their work environment? The research study aimed to explore and describe the experience of operating room nurses in their work environment and on the basis of the findings to develop guidelines to assist the operating room nurses in coping more effectively with their work environment. The researcher used a qualitative approach with an explorative, descriptive and contextual design. Fifteen registered nurses were selected using purposive sampling. Informed consent was obtained from the participants and permission from the Ethics Committee of the Nelson Mandela Metropolitan University, as well as Yekatit 12 Hospital. Data were gathered using face to face interviews and field notes were taken to determine the experiences of the participants. Data were analyzed using Tesch's method of descriptive data analysis (in Creswell, 2003:13). Two main themes with two sub-themes related to the experience of the registered nurses working in the operating room of the state hospital were identified. Main theme one focused on the non-conducive work environment and it focused on the lack of support from management and the problems experienced in the environment. It was found that OR nurses had good working relationships among the nursing staff. Main theme two focused on the limited training opportunities in OR techniques. The sub-themes described the limited exposure to new technology and the quality of nursing education which the participants felt was not taken seriously in Ethiopia. Based on the identified themes guidelines were formulated to assist the registered nurses working in the operating room of a state hospital in Ethiopia. Utilization of these guidelines should assist the registered nurses to cope more effectively with their work environment. Recommendation were made, further research and limitations identified.
- Full Text:
- Date Issued: 2012
- Authors: Woldehawariat, Negat
- Date: 2012
- Subjects: Operating room nurses -- Ethiopia , Operating rooms -- Ethiopia , Work environment -- Ethiopia
- Language: English
- Type: Thesis , Masters , MCur
- Identifier: vital:10024 , http://hdl.handle.net/10948/d1008177 , Operating room nurses -- Ethiopia , Operating rooms -- Ethiopia , Work environment -- Ethiopia
- Description: Operating room nursing skills are some of the most demanding skills in the nursing profession. At the moment nurses trained in operating room technique are in very short supply in Ethiopia, due to the exodus of nurses to better working environments with more reasonable payment. This is especially noticeable in one of the state hospitals in Addis Ababa, Ethiopia, as emerged in conversations with the head nurse of the operating room in this hospital about the high turnover rate, as well as the high absenteeism rate amongst the nurses working in the operating room. Nurses working in the operating room also expressed unhappiness in their work environment which could cause them to look for other jobs or to be absent from duty. The nurses were facing numerous problems in their work environment such as work overload due to staff shortage, stress due to shortage of supplies because they are not able to do their job as much as the need requires. The researcher identified the need to explore the challenges that the operating room nurses are experiencing in their work environment. The researcher used the following questions to meet the research objectives: What are the experiences of the operating room nurses in their work environment?; What potential assistance would such nurses need to better cope with the problems they experience in their work environment? The research study aimed to explore and describe the experience of operating room nurses in their work environment and on the basis of the findings to develop guidelines to assist the operating room nurses in coping more effectively with their work environment. The researcher used a qualitative approach with an explorative, descriptive and contextual design. Fifteen registered nurses were selected using purposive sampling. Informed consent was obtained from the participants and permission from the Ethics Committee of the Nelson Mandela Metropolitan University, as well as Yekatit 12 Hospital. Data were gathered using face to face interviews and field notes were taken to determine the experiences of the participants. Data were analyzed using Tesch's method of descriptive data analysis (in Creswell, 2003:13). Two main themes with two sub-themes related to the experience of the registered nurses working in the operating room of the state hospital were identified. Main theme one focused on the non-conducive work environment and it focused on the lack of support from management and the problems experienced in the environment. It was found that OR nurses had good working relationships among the nursing staff. Main theme two focused on the limited training opportunities in OR techniques. The sub-themes described the limited exposure to new technology and the quality of nursing education which the participants felt was not taken seriously in Ethiopia. Based on the identified themes guidelines were formulated to assist the registered nurses working in the operating room of a state hospital in Ethiopia. Utilization of these guidelines should assist the registered nurses to cope more effectively with their work environment. Recommendation were made, further research and limitations identified.
- Full Text:
- Date Issued: 2012
On the design of concentrator photovoltaic modules
- Authors: Schultz, Ross Dane
- Date: 2012
- Subjects: Photovoltaic cells -- Design and construction , Photovoltaic cells
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10546 , http://hdl.handle.net/10948/d1015766 , Photovoltaic cells -- Design and construction , Photovoltaic cells
- Description: High concentration photovoltaics (HCPV) promise a more efficient, higher power output than traditional photovoltaic modules. This is achieved by concentrating sunlight onto a small 1 cm2 triple junction (CTJ) InGaP/InGaAs/Ge cell by using precision optics. In order to achieve high performance, careful and informed design decisions must be made in the development of a HCPV module . This project investigated the design of a HCPV module and is divided into sections that concentrate on the optical design, thermal dissipation and electrical characterization of a concentration triple junction cell. The first HCPV module (Module I) design was based on the Sandia III Baseline Fresnel module which comprised of a Fresnel lens and truncated reflective secondary as the optical elements. The parameters of the CTJ cell in Module I increased with increased concentration. This included the short circuit current, open circuit voltage, power and efficiency. The best performance achieved was at 336 times operational concentration which produced 10.3 W per cell, a cell efficiency of 38.4 percent, and module efficiency of 24.2 percent Investigation of the optical subsystem revealed that the optics played a large role in the operation of the CTJ cell. Characterization of the optical elements showed a transmission loss of 15 percent of concentrated sunlight for the irradiance of which 66 percent of the loss occurred in wavelength region where the InGaP subcell is active. Characterization of the optical subsystem indicated regions of non-uniform irradiance and spectral intensity across the CTJ cell surface. The optical subsystem caused the InGaP subcell of the series monolithic connected CTJ cell to be current limiting. This was confirmed by the CTJ cell having the same short circuit current as the InGaP subcell. The performance of the CTJ cell decreased with an increase in operational temperature. A form of thermal dissipation was needed as 168 times more heat needs to be dissipated when compared to a flat plate photovoltaic module. The thermal dissipation was achieved by passive means with a heat sink which reduced the operational temperature of the CTJ cell from 50 oC to 21 oC above ambient. Cell damage was noted in Module I due to bubbles in the encapsulation epoxy bursting from a high, non-uniform intensity distribution. The development of the second module (Module II) employed a pre-monitoring criteria that characterized the CTJ cells and eliminated faulty cells from the system. These criteria included visual inspection of the cell, electroluminescence and one sun current-voltage (I-V) characteristic curves. Module II was designed as separate units which comprised of a Fresnel lens, refractive secondary, CTJ cell and heatsink. The optimal configuration between the two modules were compared. The CTJ cells in module II showed no form of degradation in the I-V characteristics and in the detected defects. The units under thermal and optical stress showed a progressive degradation. A feature in the I-V curve at V > Vmax was noted for the thermally stressed unit. This feature in the I-V curve may be attributed to the breakdown of the Ge subcell in the CTJ cell. Based on the results obtained from the two experimental HCPV modules, recommendations for an optimal HCPV module were made.
- Full Text:
- Date Issued: 2012
- Authors: Schultz, Ross Dane
- Date: 2012
- Subjects: Photovoltaic cells -- Design and construction , Photovoltaic cells
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10546 , http://hdl.handle.net/10948/d1015766 , Photovoltaic cells -- Design and construction , Photovoltaic cells
- Description: High concentration photovoltaics (HCPV) promise a more efficient, higher power output than traditional photovoltaic modules. This is achieved by concentrating sunlight onto a small 1 cm2 triple junction (CTJ) InGaP/InGaAs/Ge cell by using precision optics. In order to achieve high performance, careful and informed design decisions must be made in the development of a HCPV module . This project investigated the design of a HCPV module and is divided into sections that concentrate on the optical design, thermal dissipation and electrical characterization of a concentration triple junction cell. The first HCPV module (Module I) design was based on the Sandia III Baseline Fresnel module which comprised of a Fresnel lens and truncated reflective secondary as the optical elements. The parameters of the CTJ cell in Module I increased with increased concentration. This included the short circuit current, open circuit voltage, power and efficiency. The best performance achieved was at 336 times operational concentration which produced 10.3 W per cell, a cell efficiency of 38.4 percent, and module efficiency of 24.2 percent Investigation of the optical subsystem revealed that the optics played a large role in the operation of the CTJ cell. Characterization of the optical elements showed a transmission loss of 15 percent of concentrated sunlight for the irradiance of which 66 percent of the loss occurred in wavelength region where the InGaP subcell is active. Characterization of the optical subsystem indicated regions of non-uniform irradiance and spectral intensity across the CTJ cell surface. The optical subsystem caused the InGaP subcell of the series monolithic connected CTJ cell to be current limiting. This was confirmed by the CTJ cell having the same short circuit current as the InGaP subcell. The performance of the CTJ cell decreased with an increase in operational temperature. A form of thermal dissipation was needed as 168 times more heat needs to be dissipated when compared to a flat plate photovoltaic module. The thermal dissipation was achieved by passive means with a heat sink which reduced the operational temperature of the CTJ cell from 50 oC to 21 oC above ambient. Cell damage was noted in Module I due to bubbles in the encapsulation epoxy bursting from a high, non-uniform intensity distribution. The development of the second module (Module II) employed a pre-monitoring criteria that characterized the CTJ cells and eliminated faulty cells from the system. These criteria included visual inspection of the cell, electroluminescence and one sun current-voltage (I-V) characteristic curves. Module II was designed as separate units which comprised of a Fresnel lens, refractive secondary, CTJ cell and heatsink. The optimal configuration between the two modules were compared. The CTJ cells in module II showed no form of degradation in the I-V characteristics and in the detected defects. The units under thermal and optical stress showed a progressive degradation. A feature in the I-V curve at V > Vmax was noted for the thermally stressed unit. This feature in the I-V curve may be attributed to the breakdown of the Ge subcell in the CTJ cell. Based on the results obtained from the two experimental HCPV modules, recommendations for an optimal HCPV module were made.
- Full Text:
- Date Issued: 2012
A self-reflexive investigation into effective translation strategies with reference to Jeanne Goosen's Louoond
- Authors: Minnaar, Rae-Ann
- Date: 2012
- Subjects: Translating and interpreting -- South Africa , Afrikaans fiction -- Translating -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8364 , http://hdl.handle.net/10948/d1008401 , Translating and interpreting -- South Africa , Afrikaans fiction -- Translating -- South Africa
- Description: This dissertation is a self-reflexive study into effective translation strategies. The study focuses primarily on the translation strategies by Vinay and Darbelnet (1995), namely direct and oblique strategies of translation. The strategies are used in the translation of Jeanne Goosen‘s novel Louoond (1987). The novel was chosen on account of the writer‘s unique writing style and the challenges it poses for the prospective translator. One of the key objectives of this study was to comprehensively illustrate Vinay and Darbelnet‘s strategies of translation when translating the novel. The theoretical framework of this study is an analysis of Vinay and Darbelnet‘s translation strategies. The study also aims to give insight into what is meant by translation, translation theory, literary theory and literary translation. The translation of the novel is the final product, but in order to illustrate each procedure of Vinay and Darbelnet (1995) examples were taken from this final product. The chapters that follow illustrate the strategies of Vinay and Darbelnet (1995) as used in the translation of an Afrikaans text (SL) into English (TL). Conclusions can then be drawn as to whether full equivalence was obtained and whether the translation is deemed successful.
- Full Text:
- Date Issued: 2012
- Authors: Minnaar, Rae-Ann
- Date: 2012
- Subjects: Translating and interpreting -- South Africa , Afrikaans fiction -- Translating -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8364 , http://hdl.handle.net/10948/d1008401 , Translating and interpreting -- South Africa , Afrikaans fiction -- Translating -- South Africa
- Description: This dissertation is a self-reflexive study into effective translation strategies. The study focuses primarily on the translation strategies by Vinay and Darbelnet (1995), namely direct and oblique strategies of translation. The strategies are used in the translation of Jeanne Goosen‘s novel Louoond (1987). The novel was chosen on account of the writer‘s unique writing style and the challenges it poses for the prospective translator. One of the key objectives of this study was to comprehensively illustrate Vinay and Darbelnet‘s strategies of translation when translating the novel. The theoretical framework of this study is an analysis of Vinay and Darbelnet‘s translation strategies. The study also aims to give insight into what is meant by translation, translation theory, literary theory and literary translation. The translation of the novel is the final product, but in order to illustrate each procedure of Vinay and Darbelnet (1995) examples were taken from this final product. The chapters that follow illustrate the strategies of Vinay and Darbelnet (1995) as used in the translation of an Afrikaans text (SL) into English (TL). Conclusions can then be drawn as to whether full equivalence was obtained and whether the translation is deemed successful.
- Full Text:
- Date Issued: 2012
Megaherbivores in succulent thicket: resource use and implications
- Authors: Landman, Marietjie
- Date: 2012
- Subjects: Elephants , African elephant , Black rhinoceros , Succulent plants
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10689 , http://hdl.handle.net/10948/d1007956 , Elephants , African elephant , Black rhinoceros , Succulent plants
- Description: This study aims to develop a predictive understanding of the resource use, impacts and interactions of elephant Loxodonta africana and black rhinoceros Diceros bicornis in the succulent thickets of the Eastern Cape, South Africa. While these megaherbivores typically dominate the biomass, elephant are more abundant, such that their impacts off-set that of all other herbivores. Consequently, this thesis has three main foci: first, developing a mechanistic understanding of the influences of elephant; second, developing predictive insights into elephant impacts on plant communities; finally, an understanding of the knockon-effects of the impacts for coexisting rhinoceros. Thus, by documenting the diet and dietary preferences of elephant, I firstly show that only about 18 percent of the species previously thought vulnerable to herbivory, occur in the diet. This refutes the generally held belief that elephant herbivory is the primary driver of decline among plants, and emphasizes the likely contribution of other mechanisms (e.g. trampling, knock-on-effects, etc.). Thus, the accurate prediction of the impacts caused by elephant requires an understanding of previously marginalized mechanisms. From here, I quantify >50 years of impacts on the thicket shrub community and test their spatial and temporal extent near water. I confirm the vulnerability of thicket to transformation (particularly near water) as the accumulated influences of elephant reduce community composition and structure, and predict that these impacts will eventually bring about landscape-level degradation and a significant loss of biodiversity. Importantly, results show an uneven distribution of effects between elements of this community: from community composition and structure, to the structure of individual canopy species and ecological functioning. While these findings confound our interpretation of the extent of the impacts, it demonstrates the importance of explicitly recognizing biodiversity and heterogeneity for the conservation management of elephant. Finally, I test the consequences of the impacts for coexisting rhinoceros. While I show that this causes rhinoceros to change their foraging strategies in the presence of elephant at high densities, I also show that elephant may facilitate access to food for rhinoceros at reduced densities. These findings indicate the importance of elephant in driving the structure and composition of the thicket shrub community and the consequences of this for coexisting large herbivores. Thus, developing a predictive understanding of the spatial and temporal variations of elephant impacts between elements of biodiversity and the mechanisms driving these changes are key to their management. This implies that the effective conservation management of elephant can only be achieved through the careful, scientific design of monitoring programmes.
- Full Text:
- Date Issued: 2012
- Authors: Landman, Marietjie
- Date: 2012
- Subjects: Elephants , African elephant , Black rhinoceros , Succulent plants
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10689 , http://hdl.handle.net/10948/d1007956 , Elephants , African elephant , Black rhinoceros , Succulent plants
- Description: This study aims to develop a predictive understanding of the resource use, impacts and interactions of elephant Loxodonta africana and black rhinoceros Diceros bicornis in the succulent thickets of the Eastern Cape, South Africa. While these megaherbivores typically dominate the biomass, elephant are more abundant, such that their impacts off-set that of all other herbivores. Consequently, this thesis has three main foci: first, developing a mechanistic understanding of the influences of elephant; second, developing predictive insights into elephant impacts on plant communities; finally, an understanding of the knockon-effects of the impacts for coexisting rhinoceros. Thus, by documenting the diet and dietary preferences of elephant, I firstly show that only about 18 percent of the species previously thought vulnerable to herbivory, occur in the diet. This refutes the generally held belief that elephant herbivory is the primary driver of decline among plants, and emphasizes the likely contribution of other mechanisms (e.g. trampling, knock-on-effects, etc.). Thus, the accurate prediction of the impacts caused by elephant requires an understanding of previously marginalized mechanisms. From here, I quantify >50 years of impacts on the thicket shrub community and test their spatial and temporal extent near water. I confirm the vulnerability of thicket to transformation (particularly near water) as the accumulated influences of elephant reduce community composition and structure, and predict that these impacts will eventually bring about landscape-level degradation and a significant loss of biodiversity. Importantly, results show an uneven distribution of effects between elements of this community: from community composition and structure, to the structure of individual canopy species and ecological functioning. While these findings confound our interpretation of the extent of the impacts, it demonstrates the importance of explicitly recognizing biodiversity and heterogeneity for the conservation management of elephant. Finally, I test the consequences of the impacts for coexisting rhinoceros. While I show that this causes rhinoceros to change their foraging strategies in the presence of elephant at high densities, I also show that elephant may facilitate access to food for rhinoceros at reduced densities. These findings indicate the importance of elephant in driving the structure and composition of the thicket shrub community and the consequences of this for coexisting large herbivores. Thus, developing a predictive understanding of the spatial and temporal variations of elephant impacts between elements of biodiversity and the mechanisms driving these changes are key to their management. This implies that the effective conservation management of elephant can only be achieved through the careful, scientific design of monitoring programmes.
- Full Text:
- Date Issued: 2012
A comparative study on the sensitive detection of hydroxyl radical using thiol-capped CdTe and CdTe/ZnS quantum dots
- Adegoke, Oluwasesan, Nyokong, Tebello
- Authors: Adegoke, Oluwasesan , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/242778 , vital:51077 , xlink:href="https://doi.org/10.1007/s10895-012-1089-2"
- Description: Four types of water-soluble luminescent quantum dots (QDs) whose surface was functionlaized with thioglycolic acid (TGA), 3-mercaptopropionic acid (MPA), or glutathione (GSH), were investigated for the sensitive and selective detection of hydroxyl radical (●OH) in aqueous media. It was found that the type of capping agent and QD influenced the sensitivity of the probe. The order of sensitivity of the probe was: GSH-CdTe@ZnS > MPA-CdTe@ZnS > TGA-CdTe > MPA-CdTe QDs. Under the optimum conditions, a limit of detection as low as 8.5 × 10-8 M was obtained using GSH-CdTe@ZnS. The effects of foreign reactive oxygen species and the Fenton reactants and products as possible interferences on the proposed probe were negligible for CdTe@ZnS QDs. Besides, experimental results indicated that CdTe@ZnS QDs were more attractive for the selective recognition of ●OH than CdTe QDs. The mechanistic reaction pathway between the QDs and ●OH is proposed.
- Full Text:
- Date Issued: 2012
- Authors: Adegoke, Oluwasesan , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/242778 , vital:51077 , xlink:href="https://doi.org/10.1007/s10895-012-1089-2"
- Description: Four types of water-soluble luminescent quantum dots (QDs) whose surface was functionlaized with thioglycolic acid (TGA), 3-mercaptopropionic acid (MPA), or glutathione (GSH), were investigated for the sensitive and selective detection of hydroxyl radical (●OH) in aqueous media. It was found that the type of capping agent and QD influenced the sensitivity of the probe. The order of sensitivity of the probe was: GSH-CdTe@ZnS > MPA-CdTe@ZnS > TGA-CdTe > MPA-CdTe QDs. Under the optimum conditions, a limit of detection as low as 8.5 × 10-8 M was obtained using GSH-CdTe@ZnS. The effects of foreign reactive oxygen species and the Fenton reactants and products as possible interferences on the proposed probe were negligible for CdTe@ZnS QDs. Besides, experimental results indicated that CdTe@ZnS QDs were more attractive for the selective recognition of ●OH than CdTe QDs. The mechanistic reaction pathway between the QDs and ●OH is proposed.
- Full Text:
- Date Issued: 2012
Towards integrated catchment management : challenges surrounding implementation in the Gamtoos River catchment
- Authors: Materechera, Fenji
- Date: 2012
- Subjects: Watershed management -- South Africa , Watershed management -- South Africa -- Citizen participation , Integrated water development -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10664 , http://hdl.handle.net/10948/d1018553
- Description: Water resource management has become a pertinent issue of global environmental concern in response to the conditions of a growing global population, increasing development and a limited freshwater supply. It is against the backdrop of such conditions that effective water resource management has gained popularity in seeking to ensure that the needs of the growing population will be met and secured for future generations. The notion of integrated water resource management (IWRM) is a perspective on water resource management that has evolved out of the global opinion that social and ecological systems are linked and therefore cannot be managed separately. The department of water affairs (DWA) in South Africa highlights the importance of approaching management of water resources from a catchment perspective which forms the basis for a particular integrated approach to management called integrated catchment management (ICM). ICM recognizes the catchment as the correct administrative unit for management. It integrates water resources and the land that forms the catchment area in planning and management. Researchers have described the implementation of ICM as being complicated and difficult. This is no exception to South Africa. Principles of ICM have received widespread prominence in South Africa as they have been incorporated into national water policy. Actual implementation however is still in its infancy. The study is therefore a case study of ICM with respect to factors influencing implementation amongst different stakeholders. The study aims to explore the theme of implementation of ICM within the context of the Gamtoos River Catchment with a view toward identifying and addressing challenges that may be more broadly applicable. The study adopts an inductive, exploratory approach to the connection between theory and practice. A systems-based framework characterized by sequential steps similar to that employed in a case study conducted by Bellamy et al. (2001) in Queensland Australia is used to facilitate the evaluation of ICM in the Gamtoos River Catchment. The evaluation is achieved through a three step process of exploration in the current study. Triangulation is applied to the choice of methods of analysis which involves the use of a global analysis method, the use of learning scenarios and a grounded theory method. Findings reveal seven core themes which help to provide a detailed, contextual understanding relating to the status quo for ICM in the catchment. Results from a grounded theory analysis summarized the main challenges to implementation into five broad categories. Based on this analysis method and the application of the three learning scenarios for the Gamtoos River Catchment, the extent to which these challenges exist was discovered. The state of ICM in the catchment was classified as falling within a condition of a level of success being achieved with room for improvement to a condition of optimal ICM. The study concludes that based on the context of ICM being an example of a Complex Adaptive Systems (CAS), this state of ICM in the Gamtoos River Catchment is subject to change. This therefore necessitates the consideration of approaches to implementation that are adaptive to change. Findings may serve to inform decision making on how ICM can be effectively implemented elsewhere in a South African context.
- Full Text:
- Date Issued: 2012
- Authors: Materechera, Fenji
- Date: 2012
- Subjects: Watershed management -- South Africa , Watershed management -- South Africa -- Citizen participation , Integrated water development -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10664 , http://hdl.handle.net/10948/d1018553
- Description: Water resource management has become a pertinent issue of global environmental concern in response to the conditions of a growing global population, increasing development and a limited freshwater supply. It is against the backdrop of such conditions that effective water resource management has gained popularity in seeking to ensure that the needs of the growing population will be met and secured for future generations. The notion of integrated water resource management (IWRM) is a perspective on water resource management that has evolved out of the global opinion that social and ecological systems are linked and therefore cannot be managed separately. The department of water affairs (DWA) in South Africa highlights the importance of approaching management of water resources from a catchment perspective which forms the basis for a particular integrated approach to management called integrated catchment management (ICM). ICM recognizes the catchment as the correct administrative unit for management. It integrates water resources and the land that forms the catchment area in planning and management. Researchers have described the implementation of ICM as being complicated and difficult. This is no exception to South Africa. Principles of ICM have received widespread prominence in South Africa as they have been incorporated into national water policy. Actual implementation however is still in its infancy. The study is therefore a case study of ICM with respect to factors influencing implementation amongst different stakeholders. The study aims to explore the theme of implementation of ICM within the context of the Gamtoos River Catchment with a view toward identifying and addressing challenges that may be more broadly applicable. The study adopts an inductive, exploratory approach to the connection between theory and practice. A systems-based framework characterized by sequential steps similar to that employed in a case study conducted by Bellamy et al. (2001) in Queensland Australia is used to facilitate the evaluation of ICM in the Gamtoos River Catchment. The evaluation is achieved through a three step process of exploration in the current study. Triangulation is applied to the choice of methods of analysis which involves the use of a global analysis method, the use of learning scenarios and a grounded theory method. Findings reveal seven core themes which help to provide a detailed, contextual understanding relating to the status quo for ICM in the catchment. Results from a grounded theory analysis summarized the main challenges to implementation into five broad categories. Based on this analysis method and the application of the three learning scenarios for the Gamtoos River Catchment, the extent to which these challenges exist was discovered. The state of ICM in the catchment was classified as falling within a condition of a level of success being achieved with room for improvement to a condition of optimal ICM. The study concludes that based on the context of ICM being an example of a Complex Adaptive Systems (CAS), this state of ICM in the Gamtoos River Catchment is subject to change. This therefore necessitates the consideration of approaches to implementation that are adaptive to change. Findings may serve to inform decision making on how ICM can be effectively implemented elsewhere in a South African context.
- Full Text:
- Date Issued: 2012
Comparative biogeography and ecology of freshwater fishes in the Breede and associated river systems, South Africa
- Authors: Chakona, Albert
- Date: 2012
- Subjects: Freshwater fishes -- South Africa -- Breede River , Freshwater fishes -- South Africa -- Geographical distribution , Freshwater fishes -- Ecology , Feshwater fishes -- Genetics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5372 , http://hdl.handle.net/10962/d1015694
- Description: Distribution patterns and levels of genetic diversity in extant taxa are a product of complex palaeogeographic processes and climatic oscillations as well as the species’ intrinsic ecological adaptations. The Cape Floristic Region of South Africa presents a unique system for studying the processes that promote species diversification and distribution patterns. This region has a high degree of endemism of both terrestrial and aquatic biota and is clearly isolated from neighbouring areas by the Cape Fold Mountains and the Great Escarpment. The objective of this study was to firstly examine the ecology of freshwater fishes belonging to the genera Galaxias, Pseudobarbus and Sandelia in the south-western CFR. This was followed by an assessment of the genetic diversity of these taxa. Unique lineages were identified and their distribution was mapped. The work aimed to explore the role of the region’s complex palaeogeographic and climatic history as well as the role of the species’ ecological adaptations in driving lineage diversification and shaping contemporary distribution patterns. The four main components of the study can be summarised as follows: 1. Habitat associations of three widely distributed lineages of Galaxias zebratus Pseudobarbus burchelli and Sandelia capensis were evaluated at multiple localities in minimally disturbed mountain tributaries of the Breede, Duiwenhoks and Goukou River systems. The lineages have distinct habitat associations which were related to differences in their morphological traits. The slender-bodied Galaxias ‘nebula’ and the fusiform-shaped Pseudobarbus ‘Breede’ are capable of exploiting upper reaches with faster water velocity. By contrast, the laterally compressed Sandelia ‘eastern’ is restricted to lower reaches, making this lineage more susceptible to a wide array of impacts. 2. A recently discovered lineage of Galaxias zebratus, (Galaxias ‘nebula’), was found to be capable of tolerating emersion for a prolonged period of time. This is the first time that such capabilities have been documented in an African galaxiid. These adaptations have implications for the interpretation of Galaxias ‘nebula’s wide distribution range. 3. The phylogeography of Galaxias ‘nebula’ across its entire distribution range was investigated using two mitochondrial genes (cytochrome c oxidase subunit I (COI) and cytochrome b (cyt b)). This lineage has a complex evolutionary history that was influenced by both intrinsic and extrinsic factors. Rare events such as episodic drainage connections during Pleistocene and Holocene pluvial periods, possibly augmented by river confluences during periods of lower sea-levels and river capture events seem to be the most credible explanation for the extensive contemporary distribution and the relatively shallow genetic divergence between different river systems. 4. Mitochondrial cyt b sequences were used (i) to assess genetic diversity in G. zebratus, P. burchelli and S. capensis from the south-western CFR and (ii) to determine the roles of intrinsic ecological adaptations and extrinsic landscape and climatic changes in promoting genetic diversification and shaping present day distribution patterns of lineages in the three taxa. Marine incursions during periods of major sea-level transgressions are proposed to have isolated populations in upland refugia, thereby driving allopatric divergence in these species. Subsequent connections of rivers during wetter periods and lower sea-levels are proposed to have facilitated post-speciation dispersal of lineages to attain present day distribution patterns. While detailed morphological studies and further genetic analysis are needed to substantiate the taxonomic status of the newly discovered lineages of Galaxias zebratus, Pseudobarbus burchelli and Sandelia capensis, results of the present study indicate that the south-western CFR represents a previously unrecognised centre of freshwater fish diversity and microendemism in the broader Cape Floristic Region. Accurate identification of lineages and comprehensive mapping of their distribution is a fundamental pre-requisite for ecological studies, assessing conservation status and implementation of appropriate conservation measures.
- Full Text:
- Date Issued: 2012
- Authors: Chakona, Albert
- Date: 2012
- Subjects: Freshwater fishes -- South Africa -- Breede River , Freshwater fishes -- South Africa -- Geographical distribution , Freshwater fishes -- Ecology , Feshwater fishes -- Genetics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5372 , http://hdl.handle.net/10962/d1015694
- Description: Distribution patterns and levels of genetic diversity in extant taxa are a product of complex palaeogeographic processes and climatic oscillations as well as the species’ intrinsic ecological adaptations. The Cape Floristic Region of South Africa presents a unique system for studying the processes that promote species diversification and distribution patterns. This region has a high degree of endemism of both terrestrial and aquatic biota and is clearly isolated from neighbouring areas by the Cape Fold Mountains and the Great Escarpment. The objective of this study was to firstly examine the ecology of freshwater fishes belonging to the genera Galaxias, Pseudobarbus and Sandelia in the south-western CFR. This was followed by an assessment of the genetic diversity of these taxa. Unique lineages were identified and their distribution was mapped. The work aimed to explore the role of the region’s complex palaeogeographic and climatic history as well as the role of the species’ ecological adaptations in driving lineage diversification and shaping contemporary distribution patterns. The four main components of the study can be summarised as follows: 1. Habitat associations of three widely distributed lineages of Galaxias zebratus Pseudobarbus burchelli and Sandelia capensis were evaluated at multiple localities in minimally disturbed mountain tributaries of the Breede, Duiwenhoks and Goukou River systems. The lineages have distinct habitat associations which were related to differences in their morphological traits. The slender-bodied Galaxias ‘nebula’ and the fusiform-shaped Pseudobarbus ‘Breede’ are capable of exploiting upper reaches with faster water velocity. By contrast, the laterally compressed Sandelia ‘eastern’ is restricted to lower reaches, making this lineage more susceptible to a wide array of impacts. 2. A recently discovered lineage of Galaxias zebratus, (Galaxias ‘nebula’), was found to be capable of tolerating emersion for a prolonged period of time. This is the first time that such capabilities have been documented in an African galaxiid. These adaptations have implications for the interpretation of Galaxias ‘nebula’s wide distribution range. 3. The phylogeography of Galaxias ‘nebula’ across its entire distribution range was investigated using two mitochondrial genes (cytochrome c oxidase subunit I (COI) and cytochrome b (cyt b)). This lineage has a complex evolutionary history that was influenced by both intrinsic and extrinsic factors. Rare events such as episodic drainage connections during Pleistocene and Holocene pluvial periods, possibly augmented by river confluences during periods of lower sea-levels and river capture events seem to be the most credible explanation for the extensive contemporary distribution and the relatively shallow genetic divergence between different river systems. 4. Mitochondrial cyt b sequences were used (i) to assess genetic diversity in G. zebratus, P. burchelli and S. capensis from the south-western CFR and (ii) to determine the roles of intrinsic ecological adaptations and extrinsic landscape and climatic changes in promoting genetic diversification and shaping present day distribution patterns of lineages in the three taxa. Marine incursions during periods of major sea-level transgressions are proposed to have isolated populations in upland refugia, thereby driving allopatric divergence in these species. Subsequent connections of rivers during wetter periods and lower sea-levels are proposed to have facilitated post-speciation dispersal of lineages to attain present day distribution patterns. While detailed morphological studies and further genetic analysis are needed to substantiate the taxonomic status of the newly discovered lineages of Galaxias zebratus, Pseudobarbus burchelli and Sandelia capensis, results of the present study indicate that the south-western CFR represents a previously unrecognised centre of freshwater fish diversity and microendemism in the broader Cape Floristic Region. Accurate identification of lineages and comprehensive mapping of their distribution is a fundamental pre-requisite for ecological studies, assessing conservation status and implementation of appropriate conservation measures.
- Full Text:
- Date Issued: 2012
The influence of copreneurial relationships on the restaurant industry : a study in the Nelson Mandela Metropole
- Von Hoffman, Ethen Langeford
- Authors: Von Hoffman, Ethen Langeford
- Date: 2012
- Subjects: Couple-owned business enterprises -- Management , Entrepreneurship -- South Africa , Small business -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8839 , http://hdl.handle.net/10948/d1020003
- Description: Entrepreneurship plays an important role in the South African economy, especially in light of the recent global recession. For family businesses, namely copreneurs in the restaurant industry, to be afforded a better opportunity to perform better and be viable and sustainable, a deeper understanding and insight into their dynamics is required. Researching and implementing strategies or recommendations to improve the influence of copreneurial relationships in the restaurant industry is fundamentally important to the growth and sustainability of restaurants in the hospitality industry, in the Nelson Mandela Metropole (NMM). However, no known studies have been performed in this area of copreneurship. This study sought to present exploratory research in the rapidly expanding and critically important sector family business, namely copreneurships specifically in the restaurant industry in the NMM, in South Africa. The primary research objective of this study is to gain a deeper understanding and insight into the influence of copreneurial relationships in the restaurant industry in the NMM. A phenomenological, or qualitative, research paradigm, through the use of focused one-on-one interviews, was employed to probe and analyse relational factors of copreneurial relationships. A qualifying questionnaire was constructed to determine the most effective sample for the study followed by an extensive questionnaire constructed to probe into the demographics and the specifically identified relational factors of the ten qualifying copreneurships. The collected data was then analysed and inferences were derived from the findings of the study. The findings revealed that what restaurant copreneurships perceive to be the most important relationship factors are very closely linked to the relationship factors perceived important to personally work on and improve. Of the relational factors considered for this study, namely: Commitment, communication, conflict, division of labour, emotional attachment, relationship bond, respect, spousal harmony, trust and the spousal values system, several factors stood out as those baring greatest influence on copreneurial relationships and their business. This study, from an analysis of the collected interview data and subsequent findings, determined communication to stand out above all other factors as being the most critical to copreneurial relationships. All other factors emanated as important but division of labour, values system, respect and relationship bond were revealed as extremely important, just behind communication. In light of these findings, as well as the discovery of other affecting factors, the study concluded that the viability and sustainability of restaurant copreneurships is of paramount significance. In order to facilitate this, copreneurial couples must cherish their relationships with each other, understand the dynamics of the relational factors affecting their relationships, invoke relational improvements for their viability and sustainability, not neglect family responsibilities and preservation in light of business needs and work together as a team.
- Full Text:
- Date Issued: 2012
- Authors: Von Hoffman, Ethen Langeford
- Date: 2012
- Subjects: Couple-owned business enterprises -- Management , Entrepreneurship -- South Africa , Small business -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8839 , http://hdl.handle.net/10948/d1020003
- Description: Entrepreneurship plays an important role in the South African economy, especially in light of the recent global recession. For family businesses, namely copreneurs in the restaurant industry, to be afforded a better opportunity to perform better and be viable and sustainable, a deeper understanding and insight into their dynamics is required. Researching and implementing strategies or recommendations to improve the influence of copreneurial relationships in the restaurant industry is fundamentally important to the growth and sustainability of restaurants in the hospitality industry, in the Nelson Mandela Metropole (NMM). However, no known studies have been performed in this area of copreneurship. This study sought to present exploratory research in the rapidly expanding and critically important sector family business, namely copreneurships specifically in the restaurant industry in the NMM, in South Africa. The primary research objective of this study is to gain a deeper understanding and insight into the influence of copreneurial relationships in the restaurant industry in the NMM. A phenomenological, or qualitative, research paradigm, through the use of focused one-on-one interviews, was employed to probe and analyse relational factors of copreneurial relationships. A qualifying questionnaire was constructed to determine the most effective sample for the study followed by an extensive questionnaire constructed to probe into the demographics and the specifically identified relational factors of the ten qualifying copreneurships. The collected data was then analysed and inferences were derived from the findings of the study. The findings revealed that what restaurant copreneurships perceive to be the most important relationship factors are very closely linked to the relationship factors perceived important to personally work on and improve. Of the relational factors considered for this study, namely: Commitment, communication, conflict, division of labour, emotional attachment, relationship bond, respect, spousal harmony, trust and the spousal values system, several factors stood out as those baring greatest influence on copreneurial relationships and their business. This study, from an analysis of the collected interview data and subsequent findings, determined communication to stand out above all other factors as being the most critical to copreneurial relationships. All other factors emanated as important but division of labour, values system, respect and relationship bond were revealed as extremely important, just behind communication. In light of these findings, as well as the discovery of other affecting factors, the study concluded that the viability and sustainability of restaurant copreneurships is of paramount significance. In order to facilitate this, copreneurial couples must cherish their relationships with each other, understand the dynamics of the relational factors affecting their relationships, invoke relational improvements for their viability and sustainability, not neglect family responsibilities and preservation in light of business needs and work together as a team.
- Full Text:
- Date Issued: 2012
An analysis of pacing and sequencing of reading instruction in three grade 1 classrooms where isiXhosa is the language of learning and teaching
- Authors: Masola, Athambile
- Date: 2012
- Subjects: Reading (Elementary) -- Study and teaching -- Foreign speakers -- Research -- South Africa Literacy -- Education (Primary) -- Research -- South Africa English language -- Study and teaching -- South Africa -- Foreign speakers
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1420 , http://hdl.handle.net/10962/d1003301
- Description: Reading development in the Foundation Phase (FP) is central to children’s success as they progress through school. However, evaluations in South Africa such as the Annual National Assessments (ANAs) and the Progress in International Reading Literacy Study (PIRLS) (2006) show that reading achievement in the Foundation Phase is low, especially for children learning with African languages as their home language. This thesis examines pacing and sequencing in three Grade 1 literacy classes where isiXhosa is the language of learning and teaching (LOLT). The research took the form of a case study, focusing on the teachers’ classroom practice and how they understand their practice. Documents related to reading development in the Foundation Phase are analysed with regard to pacing and sequencing, examining how the curriculum frames literacy for teachers in the Foundation Phase. The teachers’ understanding in relation to their social context is also an important part of this research. In the thesis the way in which the teachers sequence and pace learning is analysed, drawing on Bernstein’s notions of internal and external framing, and Bourdieu’s notion of the habitus. The intended curriculum and the implemented curriculum are then compared. The results confirm that in low socio‐economic status (SES) schools, the level of poverty has an impact on teaching practice. The results also show that pacing and sequencing are reliant on the degree of planning amongst teachers. The level of development amongst learners also plays a role in how teachers organise their practice in order to differentiate the teaching of reading for all learners. The understanding that teachers have about their teaching practice are layered and influenced by their experiences, history and memories as teachers. The thesis concludes that there is a need to develop teachers’ understanding of planning and organising the teaching of reading, especially when the learners are from poor communities and do not get support in the home. In order for teachers to improve their practice, it is important for them to have the opportunity to reflect on and understand their practice.
- Full Text:
- Date Issued: 2012
- Authors: Masola, Athambile
- Date: 2012
- Subjects: Reading (Elementary) -- Study and teaching -- Foreign speakers -- Research -- South Africa Literacy -- Education (Primary) -- Research -- South Africa English language -- Study and teaching -- South Africa -- Foreign speakers
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1420 , http://hdl.handle.net/10962/d1003301
- Description: Reading development in the Foundation Phase (FP) is central to children’s success as they progress through school. However, evaluations in South Africa such as the Annual National Assessments (ANAs) and the Progress in International Reading Literacy Study (PIRLS) (2006) show that reading achievement in the Foundation Phase is low, especially for children learning with African languages as their home language. This thesis examines pacing and sequencing in three Grade 1 literacy classes where isiXhosa is the language of learning and teaching (LOLT). The research took the form of a case study, focusing on the teachers’ classroom practice and how they understand their practice. Documents related to reading development in the Foundation Phase are analysed with regard to pacing and sequencing, examining how the curriculum frames literacy for teachers in the Foundation Phase. The teachers’ understanding in relation to their social context is also an important part of this research. In the thesis the way in which the teachers sequence and pace learning is analysed, drawing on Bernstein’s notions of internal and external framing, and Bourdieu’s notion of the habitus. The intended curriculum and the implemented curriculum are then compared. The results confirm that in low socio‐economic status (SES) schools, the level of poverty has an impact on teaching practice. The results also show that pacing and sequencing are reliant on the degree of planning amongst teachers. The level of development amongst learners also plays a role in how teachers organise their practice in order to differentiate the teaching of reading for all learners. The understanding that teachers have about their teaching practice are layered and influenced by their experiences, history and memories as teachers. The thesis concludes that there is a need to develop teachers’ understanding of planning and organising the teaching of reading, especially when the learners are from poor communities and do not get support in the home. In order for teachers to improve their practice, it is important for them to have the opportunity to reflect on and understand their practice.
- Full Text:
- Date Issued: 2012
An assessment of the implementation of intervention programmes which ensure the right to education for orphans in King Williams Town District
- Authors: Ntshuntshe, Zoleka
- Date: 2012
- Subjects: Student assistance programs
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24661 , vital:63399
- Description: The purpose of the study was to assess the implementation of intervention programmes that ensure the right to education for orphans in schools in the King William’s Town District. Data from the study revealed that there were a number of challenges faced by orphans with regards to accessing social grants and this affected their school performance negatively. Some of the challenges were (1) even though orphans were receiving the social grant, it was inadequate to provide for their home and school needs; (2) there was lack of information by applicants to access documents they needed to apply for social grants. This was an impediment to access to funds from social grants. (3) The long distances travelled by people to reach social services posed obstacles to those wishing to apply for grants. (4) Applicants lacked proper documentation such as birth certificates and parents’ death certificates which could impede application processes for social grants and (5) Lack of monitoring of social grants resulted in the misuse of funds by some caregivers. In the schools it was also established that there was irregular distribution of food parcels which resulted from some people who gave food to their families and friends, leaving the needy ones out. The No fee policy however was a success as most learners were able to remain in school. With regard to school attendance, some of the challenges were: (1) that some learners were struggling to buy school books as this was not covered by the policy. (2) There was slow implementation of scholar nutrition programme with some schools in quintile 1-3 still not being able to benefit from the programme. (3) Scholar transport was not available to most of the learners and (4) learners were without counseling services, since teachers were not trained in psychosocial support. Nonetheless, social workers were adequately trained to provide psychosocial support to learners. In addition, non governmental organizations contributed a vital service by providing orphans with uniforms and food. However their work was limited by resources and funding. The study was situated in the interpretive paradigm which seeks to construct detailed descriptions of reality. The qualitative methods were suitable for data collection purposes because they allowed the use of interviews which collected detailed, authentic information of what goes on in the schools. It was therefore the best method for the research study which seeks to assess implementation of intervention programmes for orphans as they related the challenges they encounter in the implementation of intervention programmes in their schools. Purposive sampling was used to select 8 orphans, 8 caregivers, 4 principals, 4 teachers and 4 social workers from the 4 schools in the district. The study recommends that the Child Support Grant be reviewed upwards and that monitoring be strengthened so that grants are not misused. It is further recommended that the department of social services synchronize its information dissemination strategies with other stakeholder departments, such as the department of education so as to benefit orphans. It is also recommended that the No fee policy be strengthened by such additions as providing books for orphans and other vulnerable children in schools. Finally the study recommends scholar transport to be implemented as learners still have to walk long distances to school. , Thesis (MEd) -- Faculty of Education, 2012
- Full Text:
- Date Issued: 2012
- Authors: Ntshuntshe, Zoleka
- Date: 2012
- Subjects: Student assistance programs
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24661 , vital:63399
- Description: The purpose of the study was to assess the implementation of intervention programmes that ensure the right to education for orphans in schools in the King William’s Town District. Data from the study revealed that there were a number of challenges faced by orphans with regards to accessing social grants and this affected their school performance negatively. Some of the challenges were (1) even though orphans were receiving the social grant, it was inadequate to provide for their home and school needs; (2) there was lack of information by applicants to access documents they needed to apply for social grants. This was an impediment to access to funds from social grants. (3) The long distances travelled by people to reach social services posed obstacles to those wishing to apply for grants. (4) Applicants lacked proper documentation such as birth certificates and parents’ death certificates which could impede application processes for social grants and (5) Lack of monitoring of social grants resulted in the misuse of funds by some caregivers. In the schools it was also established that there was irregular distribution of food parcels which resulted from some people who gave food to their families and friends, leaving the needy ones out. The No fee policy however was a success as most learners were able to remain in school. With regard to school attendance, some of the challenges were: (1) that some learners were struggling to buy school books as this was not covered by the policy. (2) There was slow implementation of scholar nutrition programme with some schools in quintile 1-3 still not being able to benefit from the programme. (3) Scholar transport was not available to most of the learners and (4) learners were without counseling services, since teachers were not trained in psychosocial support. Nonetheless, social workers were adequately trained to provide psychosocial support to learners. In addition, non governmental organizations contributed a vital service by providing orphans with uniforms and food. However their work was limited by resources and funding. The study was situated in the interpretive paradigm which seeks to construct detailed descriptions of reality. The qualitative methods were suitable for data collection purposes because they allowed the use of interviews which collected detailed, authentic information of what goes on in the schools. It was therefore the best method for the research study which seeks to assess implementation of intervention programmes for orphans as they related the challenges they encounter in the implementation of intervention programmes in their schools. Purposive sampling was used to select 8 orphans, 8 caregivers, 4 principals, 4 teachers and 4 social workers from the 4 schools in the district. The study recommends that the Child Support Grant be reviewed upwards and that monitoring be strengthened so that grants are not misused. It is further recommended that the department of social services synchronize its information dissemination strategies with other stakeholder departments, such as the department of education so as to benefit orphans. It is also recommended that the No fee policy be strengthened by such additions as providing books for orphans and other vulnerable children in schools. Finally the study recommends scholar transport to be implemented as learners still have to walk long distances to school. , Thesis (MEd) -- Faculty of Education, 2012
- Full Text:
- Date Issued: 2012
An assessment of rural women's co-operatives in the Tsojana Village as regards meeting the objectives of sustainable livelihood and socio-economic development
- Authors: Ntsaluba, Joyce Thembela
- Date: 2012
- Subjects: Women in cooperative societies -- South Africa -- Queenstown , Women in development -- South Africa -- Queenstown
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9141 , http://hdl.handle.net/10948/d1018758
- Description: This thesis is based on an in-depth assessment of the three rural women co-operatives in the Tsojana village, within the Intsika Yethu Local Municipality, which is the largest and most rural municipality within the Chris Hani District Municipality. 95 percent of households in this municipality live in rural areas or villages (Integrated Development Plan (IDP), 2010-2011). Rural areas are characterised by high levels of poverty, deprivation, poor infrastructure, and poor linkages to markets. Rural women are the ones experiencing poverty at first hand due to the fact that they are less mobile; when food crisis hits, men tend to leave to look for work or income in towns/cities, while women stay behind to look after their families (Moyo-Mhlanga, 2001). In 1975, the World Bank addressed the question of how women can become effective in economic development, hence the establishment of Women in Development Projects to encourage them to be more involved in income-generating activities like rural projects, co-operatives (co-ops) and self-help groups. A co-operative is an autonomous association of people who join voluntarily to meet their socio-economic and cultural needs through a jointly-owned and democratically-controlled enterprise (International Labour Organization (ILO), 2002). The United Nations (UN) recognized the contribution cooperatives can make to achieve the Millennium Development Goals (MDGs) through productive employment, eradicating poverty, enhancing social integration and promoting the advancement of women. This research study was motivated by the fact that- there are various women development projects/co-operatives in Tsojana Administrative Area (A/A) which aim to improve the lives of the rural people for the better, but most of these co-ops are not sustainable and financially viable. Rural women have realized that in order to sustain development they have to integrate themselves into village development structures, as in various co-operatives, informal rural entrepreneurs and agricultural and non-farm income-generating activities. The study proposes to investigate the reasons for the failure of these co-ops to create sustainable rural livelihoods. The study further attempts to explore development strategies that will assist to transform and advance the co-ops towards sustainable development for all. It also aims to explore strategies that will alleviate poverty, create jobs, and address all factors of underdevelopment and deprivation. The overall methodological approach in this study is qualitative in nature, as it is based on the understanding of the situation from the participant‟s point of view, or perspective. It seeks to describe, investigate and explore aspects of development projects, and to also understand the aspects of socio-economic life of rural women. It combines three traditions of enquiry, i.e. case study, phenomenology, and ethnography. A non-probability type of sampling, in particular purposive sampling, was used for the study because the researcher‟s samples are based on her judgement. Interpretive research paradigm was used to allow the researcher to study meaningful social action, not just the external or observable behaviour of people, and various research tools were used to collect data. These co-operatives have been identified as struggling for survival, and lacking training, and material and financial resources. The co-operatives require support for expansion and modernizing their operations.
- Full Text:
- Date Issued: 2012
- Authors: Ntsaluba, Joyce Thembela
- Date: 2012
- Subjects: Women in cooperative societies -- South Africa -- Queenstown , Women in development -- South Africa -- Queenstown
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9141 , http://hdl.handle.net/10948/d1018758
- Description: This thesis is based on an in-depth assessment of the three rural women co-operatives in the Tsojana village, within the Intsika Yethu Local Municipality, which is the largest and most rural municipality within the Chris Hani District Municipality. 95 percent of households in this municipality live in rural areas or villages (Integrated Development Plan (IDP), 2010-2011). Rural areas are characterised by high levels of poverty, deprivation, poor infrastructure, and poor linkages to markets. Rural women are the ones experiencing poverty at first hand due to the fact that they are less mobile; when food crisis hits, men tend to leave to look for work or income in towns/cities, while women stay behind to look after their families (Moyo-Mhlanga, 2001). In 1975, the World Bank addressed the question of how women can become effective in economic development, hence the establishment of Women in Development Projects to encourage them to be more involved in income-generating activities like rural projects, co-operatives (co-ops) and self-help groups. A co-operative is an autonomous association of people who join voluntarily to meet their socio-economic and cultural needs through a jointly-owned and democratically-controlled enterprise (International Labour Organization (ILO), 2002). The United Nations (UN) recognized the contribution cooperatives can make to achieve the Millennium Development Goals (MDGs) through productive employment, eradicating poverty, enhancing social integration and promoting the advancement of women. This research study was motivated by the fact that- there are various women development projects/co-operatives in Tsojana Administrative Area (A/A) which aim to improve the lives of the rural people for the better, but most of these co-ops are not sustainable and financially viable. Rural women have realized that in order to sustain development they have to integrate themselves into village development structures, as in various co-operatives, informal rural entrepreneurs and agricultural and non-farm income-generating activities. The study proposes to investigate the reasons for the failure of these co-ops to create sustainable rural livelihoods. The study further attempts to explore development strategies that will assist to transform and advance the co-ops towards sustainable development for all. It also aims to explore strategies that will alleviate poverty, create jobs, and address all factors of underdevelopment and deprivation. The overall methodological approach in this study is qualitative in nature, as it is based on the understanding of the situation from the participant‟s point of view, or perspective. It seeks to describe, investigate and explore aspects of development projects, and to also understand the aspects of socio-economic life of rural women. It combines three traditions of enquiry, i.e. case study, phenomenology, and ethnography. A non-probability type of sampling, in particular purposive sampling, was used for the study because the researcher‟s samples are based on her judgement. Interpretive research paradigm was used to allow the researcher to study meaningful social action, not just the external or observable behaviour of people, and various research tools were used to collect data. These co-operatives have been identified as struggling for survival, and lacking training, and material and financial resources. The co-operatives require support for expansion and modernizing their operations.
- Full Text:
- Date Issued: 2012
Perceptions of commerce graduates from a selected higher education institution
- Authors: Kaliika, Michael
- Date: 2012
- Subjects: Education, Higher -- Curricula -- South Africa -- Evaluation Business education -- Curricula -- South Africa -- Evaluation Business education graduates -- South Africa -- Attitudes
- Type: Thesis , Masters , MCom
- Identifier: vital:1188 , http://hdl.handle.net/10962/d1004358
- Description: The role of higher education in developing human capital and contributing to economic growth, competitive advantage and societal progress of any country is well documented. The direct link between the economic performance of a country and the level of education of its citizens cannot be repudiated. Furthermore, the demands of a growing economy, governmental pressure and the competitive international business environment have put pressure on South African businesses. This is aggravated by a “skills crisis” and the need to deliver more goods and services to increasingly more diverse customers. There is consensus amongst experts that the shortage of skills and high-level managerial human resources in South Africa constitute a major threat to the country’s future economic development and productivity growth. As the business world becomes increasingly sophisticated and challenging, so does the need to continuously review and assess the business qualifications that equip managers to cope with the challenges facing them. The competencies that come with a Commerce degree are relevant in every corner of society from managing successful private companies, public organisations, for governments to be able to contribute to the greatest good of society, to socially effective not- for- profit organisations. Despite the importance of a degree in Commerce there are some criticisms about the degree and Commerce graduates. The problem statement of this study is therefore vested in the continuum of praise and criticisms of Commerce graduates and the Commerce curriculum and, the reported imbalances between higher education institutions and the needs of the labour market. The question is whether such praise and criticisms are justified and whether higher education institutions specifically meet the requirements and expectations of both the graduates themselves and of business practice. The primary research objective of this study was, therefore, to obtain the opinions of Commerce graduates and Commerce graduate employers on the overall perception of Commerce graduates produced by a prominent HEI in the Eastern Cape Province in South iv Africa. To achieve this objective and based on in-depth analysis of secondary sources, two independent empirical surveys, aimed at two population strata were conducted, namely: • The Commerce graduates with known email addresses (N = 1 870) were extracted from the HEI’s alumni database. A total of 231 usable questionnaires were received from these Commerce graduates. • The employers with known addresses (N = 85) were extracted from the selected HEIs Career Centre database. A total of 47 usable questionnaires were received from the employers of the Commerce graduates. The main findings in this research pertain to aspects concerning core courses in the Commerce curriculum offered by the selected HEI, management skills and traits as required in the work environment, commerce curriculum outcomes and perceived experience as a student in the Faculty of Commerce at the selected HEI and Employer perceptions on the profile of the Commerce graduate. In this regard, the main findings are therefore summarised below: • Both graduates and employers assigned high relative importance scores to seventeen of the 19 core courses, supporting the multi-functionary interdisciplinary approach to the Commerce curriculum. Concerns were expressed by the Commerce graduates with the quality of tuition they had received in most of the core courses. Likewise, employers were not always satisfied with the Commerce graduates’ proficiency in some of the core courses, relative to the importance of core courses for running a business. • The Commerce graduates and employers strongly endorsed and supported the importance of the 43 management skills and traits in the work environment. Commerce graduates expressed concerns about the extent to which their management skills and traits had been developed through tuition. Concerns about the proficiency of the Commerce graduates in all the management skills and traits, relative to the importance in the work place, were conveyed by the employers. • On average the perceptions on the outcome of studies in the Faculty of Commerce were very highly regarded by the Commerce graduates. The highest mean score was for the item “Studying in the Faculty of Commerce contributed to an increase in my knowledge and abilities.”• The perceived experience of Commerce graduates as students in the Faculty of Commerce at the selected HEI was very highly regarded, implying that the selected HEI was meeting the expectations of its Commerce graduates. • Employer perceptions of what would constitute an ideal Commerce graduate were not fully met by the profile of the actual Commerce graduate from the selected HEI.
- Full Text:
- Date Issued: 2012
- Authors: Kaliika, Michael
- Date: 2012
- Subjects: Education, Higher -- Curricula -- South Africa -- Evaluation Business education -- Curricula -- South Africa -- Evaluation Business education graduates -- South Africa -- Attitudes
- Type: Thesis , Masters , MCom
- Identifier: vital:1188 , http://hdl.handle.net/10962/d1004358
- Description: The role of higher education in developing human capital and contributing to economic growth, competitive advantage and societal progress of any country is well documented. The direct link between the economic performance of a country and the level of education of its citizens cannot be repudiated. Furthermore, the demands of a growing economy, governmental pressure and the competitive international business environment have put pressure on South African businesses. This is aggravated by a “skills crisis” and the need to deliver more goods and services to increasingly more diverse customers. There is consensus amongst experts that the shortage of skills and high-level managerial human resources in South Africa constitute a major threat to the country’s future economic development and productivity growth. As the business world becomes increasingly sophisticated and challenging, so does the need to continuously review and assess the business qualifications that equip managers to cope with the challenges facing them. The competencies that come with a Commerce degree are relevant in every corner of society from managing successful private companies, public organisations, for governments to be able to contribute to the greatest good of society, to socially effective not- for- profit organisations. Despite the importance of a degree in Commerce there are some criticisms about the degree and Commerce graduates. The problem statement of this study is therefore vested in the continuum of praise and criticisms of Commerce graduates and the Commerce curriculum and, the reported imbalances between higher education institutions and the needs of the labour market. The question is whether such praise and criticisms are justified and whether higher education institutions specifically meet the requirements and expectations of both the graduates themselves and of business practice. The primary research objective of this study was, therefore, to obtain the opinions of Commerce graduates and Commerce graduate employers on the overall perception of Commerce graduates produced by a prominent HEI in the Eastern Cape Province in South iv Africa. To achieve this objective and based on in-depth analysis of secondary sources, two independent empirical surveys, aimed at two population strata were conducted, namely: • The Commerce graduates with known email addresses (N = 1 870) were extracted from the HEI’s alumni database. A total of 231 usable questionnaires were received from these Commerce graduates. • The employers with known addresses (N = 85) were extracted from the selected HEIs Career Centre database. A total of 47 usable questionnaires were received from the employers of the Commerce graduates. The main findings in this research pertain to aspects concerning core courses in the Commerce curriculum offered by the selected HEI, management skills and traits as required in the work environment, commerce curriculum outcomes and perceived experience as a student in the Faculty of Commerce at the selected HEI and Employer perceptions on the profile of the Commerce graduate. In this regard, the main findings are therefore summarised below: • Both graduates and employers assigned high relative importance scores to seventeen of the 19 core courses, supporting the multi-functionary interdisciplinary approach to the Commerce curriculum. Concerns were expressed by the Commerce graduates with the quality of tuition they had received in most of the core courses. Likewise, employers were not always satisfied with the Commerce graduates’ proficiency in some of the core courses, relative to the importance of core courses for running a business. • The Commerce graduates and employers strongly endorsed and supported the importance of the 43 management skills and traits in the work environment. Commerce graduates expressed concerns about the extent to which their management skills and traits had been developed through tuition. Concerns about the proficiency of the Commerce graduates in all the management skills and traits, relative to the importance in the work place, were conveyed by the employers. • On average the perceptions on the outcome of studies in the Faculty of Commerce were very highly regarded by the Commerce graduates. The highest mean score was for the item “Studying in the Faculty of Commerce contributed to an increase in my knowledge and abilities.”• The perceived experience of Commerce graduates as students in the Faculty of Commerce at the selected HEI was very highly regarded, implying that the selected HEI was meeting the expectations of its Commerce graduates. • Employer perceptions of what would constitute an ideal Commerce graduate were not fully met by the profile of the actual Commerce graduate from the selected HEI.
- Full Text:
- Date Issued: 2012
The meaning of place of 'effective management' in the context of South African domestic tax law
- Authors: Daniels, Paul
- Date: 2012
- Subjects: Double taxation -- Treaties , Management
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:8960 , http://hdl.handle.net/10948/d1018822
- Description: South Africa has a residence based system of taxation in which South African tax residents are taxed on their worldwide income. A company or other artificial person is regarded as a South African resident for tax purposes if it is incorporated, established or formed in South Africa or if its ‗effective management‘ is located in South Africa. Where a tax treaty determines in terms of its tie breaker rule that an artificial person is not resident in South Africa for treaty purposes, the company will also not be regarded as a tax resident in terms of South African domestic law. Treaties to which South Africa is party will often use the effective management‘ as the tie-breaker where a person other than an individual is resident in both Contracting states in terms of the respective states‘ domestic laws. The tests of ‗incorporation, established and formed‘ provide simplicity and certainty to governments but are easily open to manipulation by taxpayers. Therefore, the legislature found it necessary to incorporate effective management‘ as a test for residency into the Act. Effective management‘ is a substance over form concept which be described as a function which embodies the periodic, most senior executive management functions, which are required for the management of the affairs of the entity as whole. The test of effective management‘ by its very nature is concerned with where the crucial decisions are made in order to make a business function. To identify the location of effective management‘ it is necessary to enquire who calls the shots‘ in the context of the management of the company as opposed to who controls the company notwithstanding that there may in certain instances be overlap between the two functions. It is submitted that any person who, on the face of it seems unconnected to a company, could effectively manage‘ a company if that person is, in substance, responsible for the most senior executive management functions of the company. The discussion paper issued by SARS recognises the principal difficulties experienced with its current interpretation of the concept and makes valuable points, concessions and recommendations. It also recognised that the 'calling of shots' by the most senior executive is a critical marker of effective management‘ and that control of a company is irrelevant in determining effective management‘. To determine who effectively manages‘ a company each situation would have to be analysed on its own as it is not possible to create a definitive rule on the concept. In many cases the nature of the entity and its modus operandi would have to be taken into account to determine effective management.
- Full Text:
- Date Issued: 2012
- Authors: Daniels, Paul
- Date: 2012
- Subjects: Double taxation -- Treaties , Management
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:8960 , http://hdl.handle.net/10948/d1018822
- Description: South Africa has a residence based system of taxation in which South African tax residents are taxed on their worldwide income. A company or other artificial person is regarded as a South African resident for tax purposes if it is incorporated, established or formed in South Africa or if its ‗effective management‘ is located in South Africa. Where a tax treaty determines in terms of its tie breaker rule that an artificial person is not resident in South Africa for treaty purposes, the company will also not be regarded as a tax resident in terms of South African domestic law. Treaties to which South Africa is party will often use the effective management‘ as the tie-breaker where a person other than an individual is resident in both Contracting states in terms of the respective states‘ domestic laws. The tests of ‗incorporation, established and formed‘ provide simplicity and certainty to governments but are easily open to manipulation by taxpayers. Therefore, the legislature found it necessary to incorporate effective management‘ as a test for residency into the Act. Effective management‘ is a substance over form concept which be described as a function which embodies the periodic, most senior executive management functions, which are required for the management of the affairs of the entity as whole. The test of effective management‘ by its very nature is concerned with where the crucial decisions are made in order to make a business function. To identify the location of effective management‘ it is necessary to enquire who calls the shots‘ in the context of the management of the company as opposed to who controls the company notwithstanding that there may in certain instances be overlap between the two functions. It is submitted that any person who, on the face of it seems unconnected to a company, could effectively manage‘ a company if that person is, in substance, responsible for the most senior executive management functions of the company. The discussion paper issued by SARS recognises the principal difficulties experienced with its current interpretation of the concept and makes valuable points, concessions and recommendations. It also recognised that the 'calling of shots' by the most senior executive is a critical marker of effective management‘ and that control of a company is irrelevant in determining effective management‘. To determine who effectively manages‘ a company each situation would have to be analysed on its own as it is not possible to create a definitive rule on the concept. In many cases the nature of the entity and its modus operandi would have to be taken into account to determine effective management.
- Full Text:
- Date Issued: 2012
Efficacy of organic and synthetic insecticides on the control of cotton pests: The bollworm complex, Helicoverpa armigera, Diparopsis castanea, Earias insulana (Noctuidae) and the leafhopper, Jacobiell
- Malinga, Lawrence Nkosikhona
- Authors: Malinga, Lawrence Nkosikhona
- Date: 2012
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11791 , http://hdl.handle.net/10353/d1006798
- Description: A research was conducted on cotton to test different plant extracts with potential insecticidal properties against bollworms (Noctuidae) and leafhoppers (Cicadellidae) for the use by small-scale, cotton farmers. The study was carried out during the 2006/07 and 2007/08 seasons at ARC Institute for Industrial Crops, Rustenburg (25°39.0 S, 27°14.4 E) in the North West Province of South Africa. Four organic insecticides, tobacco (Nicotiana tabacium), khaki weed (Tagetes minuta), thorn apple (Datura stramonium) and garlic (Allium sativum) were compared with two chemical treatments, Mospilan® (acetamiprid) and Decis® (deltamethrin), and an untreated control. The cultivar, DeltaOPAL, was planted and the trial conducted using standard practices. Overall, Decis® and tobacco treatments exhibited significantly less bollworm larvae than the other treatments. Tobacco was the most promising biological pesticide against American bollworm (Helicoverpa armigera) and spiny bollworm (Earias insulana) larvae. All the treatments were significantly effective against the red bollworm (Diparopsis castanea) larvae, but Decis® and Mospilan® provided the best control. Although khaki weed, garlic and thorn apple were promising biological pesticides against the bollworm complex, tobacco was the most effective organic treatment. Mospilan® seemed to be more effective on the control of leafhoppers (Jacobiella fascialis), followed by Decis® and tobacco. Among the plant extracts, tobacco and garlic gave higher seed cotton yields compared to the khaki weed and thorn apple during both study seasons. In 2006/07, none of the treatments reached the corresponding economic threshold levels (ETLs). In contrast, in 2007/08, only rarely were the treatments (mostly Decis® and Mospilan®) below the corresponding ETLs. These differences were attributed to the higher rainfall recorded during the 2007/08 season, which reduced the effectiveness of the treatments by partly washing away the pesticidal applications. In addition, a high weed infestation also created competition for nutrients in the soil, thus resulting in lower (0.50-1.25 ton/ha in 2007/08 vs 2.50-5.00 ton/ha in 2006/07), but acceptable cotton seed yields. In conclusion, it is suggested that some plant extracts (particularly from tobacco and garlic) can be used as a cheaper and more environment-friendly alternative to chemical insecticides for the control of bollworms and leafhoppers, although it has been demonstrated that their efficacy do not reach the one of chemical treatments. Further research in the near future is recommended.
- Full Text:
- Date Issued: 2012
- Authors: Malinga, Lawrence Nkosikhona
- Date: 2012
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11791 , http://hdl.handle.net/10353/d1006798
- Description: A research was conducted on cotton to test different plant extracts with potential insecticidal properties against bollworms (Noctuidae) and leafhoppers (Cicadellidae) for the use by small-scale, cotton farmers. The study was carried out during the 2006/07 and 2007/08 seasons at ARC Institute for Industrial Crops, Rustenburg (25°39.0 S, 27°14.4 E) in the North West Province of South Africa. Four organic insecticides, tobacco (Nicotiana tabacium), khaki weed (Tagetes minuta), thorn apple (Datura stramonium) and garlic (Allium sativum) were compared with two chemical treatments, Mospilan® (acetamiprid) and Decis® (deltamethrin), and an untreated control. The cultivar, DeltaOPAL, was planted and the trial conducted using standard practices. Overall, Decis® and tobacco treatments exhibited significantly less bollworm larvae than the other treatments. Tobacco was the most promising biological pesticide against American bollworm (Helicoverpa armigera) and spiny bollworm (Earias insulana) larvae. All the treatments were significantly effective against the red bollworm (Diparopsis castanea) larvae, but Decis® and Mospilan® provided the best control. Although khaki weed, garlic and thorn apple were promising biological pesticides against the bollworm complex, tobacco was the most effective organic treatment. Mospilan® seemed to be more effective on the control of leafhoppers (Jacobiella fascialis), followed by Decis® and tobacco. Among the plant extracts, tobacco and garlic gave higher seed cotton yields compared to the khaki weed and thorn apple during both study seasons. In 2006/07, none of the treatments reached the corresponding economic threshold levels (ETLs). In contrast, in 2007/08, only rarely were the treatments (mostly Decis® and Mospilan®) below the corresponding ETLs. These differences were attributed to the higher rainfall recorded during the 2007/08 season, which reduced the effectiveness of the treatments by partly washing away the pesticidal applications. In addition, a high weed infestation also created competition for nutrients in the soil, thus resulting in lower (0.50-1.25 ton/ha in 2007/08 vs 2.50-5.00 ton/ha in 2006/07), but acceptable cotton seed yields. In conclusion, it is suggested that some plant extracts (particularly from tobacco and garlic) can be used as a cheaper and more environment-friendly alternative to chemical insecticides for the control of bollworms and leafhoppers, although it has been demonstrated that their efficacy do not reach the one of chemical treatments. Further research in the near future is recommended.
- Full Text:
- Date Issued: 2012
Plantar pressure and impulse profiles of students from a South African university
- Authors: Kramer, Mark
- Date: 2012
- Subjects: Human mechanics , Foot -- Movements , Joints -- ange of motion , eng
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10095 , http://hdl.handle.net/10948/d1010606 , Human mechanics , Foot -- Movements , Joints -- ange of motion
- Description: Most activities of daily living and numerous modes of physical activity incorporate some form of ambulation, of which the foot and ankle constitute the first link in the kinetic chain. A change in foot or ankle structure may therefore have subsequent effects on the superincumbent joints of the human body such as the knee, hip and lower back. Plantar pressure and impulse measurements can therefore provide greater insight into the mechanics of the foot under load-bearing conditions with regards to the areas and regions of the foot that exhibit the largest pressure values and impulse figures. Hence, it is of importance to establish normative data so as to obtain a frame of reference to identify those individuals that fall outside these norms and may exhibit a larger probability of injury. Aim and Objectives: The primary aim was to identify and compare the plantar pressure distribution patterns and impulse values of students of a South African university of different gender and race groups. To realise this aim two specific objectives were set. The first was to determine whether height, weight, body mass index (BMI), gender, race, and the level of physical activity were related to the pressure and impulse values obtained, and the second was to generate reference tables from the normative data gathered. Method: The RS Footscan system was used to measure the pressure and impulse values of the foot. The characteristics that were analysed were height, weight, body mass index and the level of physical activity of the participant and their respective association with plantar pressure and impulse values obtained. This information was then used to establish normative data. A quasi-experimental study design utilising convenience sampling was implemented as the intention was to investigate as single instance in as natural a manner as possible. Convenience sampling was used with predefined inclusion and exclusion criteria. A total of 180 participants were utilised in this study and were subdivided as follows: Gender: Males (n = 90); Females (n = 90); Race: African black (n = 60); white (n = 60) and coloured (n = 60). Each race group therefore comprised of 30 males and 30 females respectively. The anthropometric profile of participants was as follows: Age (S.D.) = 22.21 (S.D. ± 2.93) years; Height (S.D.) = 169.69 (S.D. ± 8.91) cm; Weight (S.D.) = 66.97 (S.D. ± 12.01) kg; BMI (S.D.) = 23.16 (S.D. ± 3.15) kg/m2. Participants were asked to complete a questionnaire prior to testing that would identify all exclusion criteria consisting of: the presence of foot pain or deformity, acute lower extremity trauma, lower extremity surgery, exhibited problems of performance including eye, ear or cognitive impairment, diabetes mellitus or other neurological neuropathy, or the use of walking aids. Anthropometric measurements were then taken for those participants that qualified for the study. Participants were required to perform approximately five warm-up trials to familiarise themselves with the testing equipment before testing commenced. A total of ten successful trails were subsequently recorded for each participant, with three footprints being recorded per trial on the pressure platform, thereby comprising 30 footprints (15 left foot and 15 right foot) per participant that were analysed regarding pressure and impulse values. The two-step gait initiation protocol was implemented which was proven to be a valid and reliable means of assessing gait. Participants were instructed to walk at a comfortable walking speed between 1.19 – 1.60 m/s to ensure conformity between all participants as between-trial gait velocities were proven to be significantly variable. The foot was subdivided into ten anatomical areas focusing on the great toe, lesser toes, metatarsal 1, metatarsal 2, metatarsal 3, metatarsal 4, metatarsal 5, midfoot, medial heel and lateral heel. These ten areas were then grouped into one of three regions, namely the forefoot region (great toe, lesser toes, and all five metatarsal head areas), midfoot region (midfoot area), and rearfoot/heel region (medial and lateral heel areas). Once all relevant data was gathered, corrected and analysed it was used to establish normative data tables pertaining to the various gender and race groups. Results: Of the ten individual pressure and impulse areas, the second and third metatarsal heads demonstrated the highest mean peak pressure and impulse values. Once grouped into one of the three regions, the heel region was ascribed with the largest impulse and pressure values. It was established that statistically and practically significant racial pressure differences were apparent in the left and right forefoot and midfoot regions, with black and coloured individuals yielding the highest values, whereas white participants yielded the lowest. The same was true with regards to impulse figures in that both statistical and practical significant levels were established in the forefoot and midfoot regions. Black and coloured participants exhibited larger impulse values than the white participants. The level of physical activity was found to be associated with both pressure and impulse values over the various regions of the foot. Black individuals that were largely inactive as well as moderately active coloured participants yielded the highest pressure and impulse values, which were found to be statistically and practically significant over the forefoot regions. Conversely, white participants of all physical activity levels as well as coloured participants of both low and high physical activity levels exhibited the lowest pressure values over the forefoot region, which were also found to be statistically and practically significant. The anthropometric variables of height, weight and BMI were found to relate statistically to pressure and impulse values under the various regions of the foot, but none were found to be of any practical significance (r < .30). Conclusion: It was clearly established that both gender and race specific differences existed regarding plantar pressure and impulse values of the normal foot. Plantar pressure and impulse values were also associated with the level of physical activity of the individual, thereby indicating that the level of physical activity could be a contributing factor to altered pressure and impulse values. Anthropometric variables such as height, weight and BMI could not solely account for the variances observed in pressure and impulse. Further research is required to determine whether pressure or impulse values above or below those obtained predispose an individual to injury and to contrast between various activity or sporting codes and the effect of these on plantar pressure and impulse figures. Finally, from the collected data one was able to establish reference tables for the specific gender and race groups for both plantar pressure and impulse values. This enables one to classify individuals based on the pressure and impulse values generated.
- Full Text:
- Date Issued: 2012
- Authors: Kramer, Mark
- Date: 2012
- Subjects: Human mechanics , Foot -- Movements , Joints -- ange of motion , eng
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10095 , http://hdl.handle.net/10948/d1010606 , Human mechanics , Foot -- Movements , Joints -- ange of motion
- Description: Most activities of daily living and numerous modes of physical activity incorporate some form of ambulation, of which the foot and ankle constitute the first link in the kinetic chain. A change in foot or ankle structure may therefore have subsequent effects on the superincumbent joints of the human body such as the knee, hip and lower back. Plantar pressure and impulse measurements can therefore provide greater insight into the mechanics of the foot under load-bearing conditions with regards to the areas and regions of the foot that exhibit the largest pressure values and impulse figures. Hence, it is of importance to establish normative data so as to obtain a frame of reference to identify those individuals that fall outside these norms and may exhibit a larger probability of injury. Aim and Objectives: The primary aim was to identify and compare the plantar pressure distribution patterns and impulse values of students of a South African university of different gender and race groups. To realise this aim two specific objectives were set. The first was to determine whether height, weight, body mass index (BMI), gender, race, and the level of physical activity were related to the pressure and impulse values obtained, and the second was to generate reference tables from the normative data gathered. Method: The RS Footscan system was used to measure the pressure and impulse values of the foot. The characteristics that were analysed were height, weight, body mass index and the level of physical activity of the participant and their respective association with plantar pressure and impulse values obtained. This information was then used to establish normative data. A quasi-experimental study design utilising convenience sampling was implemented as the intention was to investigate as single instance in as natural a manner as possible. Convenience sampling was used with predefined inclusion and exclusion criteria. A total of 180 participants were utilised in this study and were subdivided as follows: Gender: Males (n = 90); Females (n = 90); Race: African black (n = 60); white (n = 60) and coloured (n = 60). Each race group therefore comprised of 30 males and 30 females respectively. The anthropometric profile of participants was as follows: Age (S.D.) = 22.21 (S.D. ± 2.93) years; Height (S.D.) = 169.69 (S.D. ± 8.91) cm; Weight (S.D.) = 66.97 (S.D. ± 12.01) kg; BMI (S.D.) = 23.16 (S.D. ± 3.15) kg/m2. Participants were asked to complete a questionnaire prior to testing that would identify all exclusion criteria consisting of: the presence of foot pain or deformity, acute lower extremity trauma, lower extremity surgery, exhibited problems of performance including eye, ear or cognitive impairment, diabetes mellitus or other neurological neuropathy, or the use of walking aids. Anthropometric measurements were then taken for those participants that qualified for the study. Participants were required to perform approximately five warm-up trials to familiarise themselves with the testing equipment before testing commenced. A total of ten successful trails were subsequently recorded for each participant, with three footprints being recorded per trial on the pressure platform, thereby comprising 30 footprints (15 left foot and 15 right foot) per participant that were analysed regarding pressure and impulse values. The two-step gait initiation protocol was implemented which was proven to be a valid and reliable means of assessing gait. Participants were instructed to walk at a comfortable walking speed between 1.19 – 1.60 m/s to ensure conformity between all participants as between-trial gait velocities were proven to be significantly variable. The foot was subdivided into ten anatomical areas focusing on the great toe, lesser toes, metatarsal 1, metatarsal 2, metatarsal 3, metatarsal 4, metatarsal 5, midfoot, medial heel and lateral heel. These ten areas were then grouped into one of three regions, namely the forefoot region (great toe, lesser toes, and all five metatarsal head areas), midfoot region (midfoot area), and rearfoot/heel region (medial and lateral heel areas). Once all relevant data was gathered, corrected and analysed it was used to establish normative data tables pertaining to the various gender and race groups. Results: Of the ten individual pressure and impulse areas, the second and third metatarsal heads demonstrated the highest mean peak pressure and impulse values. Once grouped into one of the three regions, the heel region was ascribed with the largest impulse and pressure values. It was established that statistically and practically significant racial pressure differences were apparent in the left and right forefoot and midfoot regions, with black and coloured individuals yielding the highest values, whereas white participants yielded the lowest. The same was true with regards to impulse figures in that both statistical and practical significant levels were established in the forefoot and midfoot regions. Black and coloured participants exhibited larger impulse values than the white participants. The level of physical activity was found to be associated with both pressure and impulse values over the various regions of the foot. Black individuals that were largely inactive as well as moderately active coloured participants yielded the highest pressure and impulse values, which were found to be statistically and practically significant over the forefoot regions. Conversely, white participants of all physical activity levels as well as coloured participants of both low and high physical activity levels exhibited the lowest pressure values over the forefoot region, which were also found to be statistically and practically significant. The anthropometric variables of height, weight and BMI were found to relate statistically to pressure and impulse values under the various regions of the foot, but none were found to be of any practical significance (r < .30). Conclusion: It was clearly established that both gender and race specific differences existed regarding plantar pressure and impulse values of the normal foot. Plantar pressure and impulse values were also associated with the level of physical activity of the individual, thereby indicating that the level of physical activity could be a contributing factor to altered pressure and impulse values. Anthropometric variables such as height, weight and BMI could not solely account for the variances observed in pressure and impulse. Further research is required to determine whether pressure or impulse values above or below those obtained predispose an individual to injury and to contrast between various activity or sporting codes and the effect of these on plantar pressure and impulse figures. Finally, from the collected data one was able to establish reference tables for the specific gender and race groups for both plantar pressure and impulse values. This enables one to classify individuals based on the pressure and impulse values generated.
- Full Text:
- Date Issued: 2012
Public participation in integrated development planning, New Brighton, Nelson Mandela Bay Municipality : 2006-2010
- Authors: Mbewana, Stembiso Matthews
- Date: 2012
- Subjects: Local government -- South Africa -- Port Elizabeth -- Citizen participation , Local governement -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: vital:8178 , http://hdl.handle.net/10948/1775 , Local government -- South Africa -- Port Elizabeth -- Citizen participation , Local governement -- South Africa -- Port Elizabeth
- Description: The most important difference between the new form of local government and that of the past is the creative and dynamic “developmental role” for local government to ensure maximum impact on poverty alleviation within resource constraints, and to address spatially entrenched socio‐economic inequalities. This needs to take place within the framework of integrated development planning, which is linked to the annual budgeting cycles. The IDP process is intended to provide communities with opportunities for participation in articulating, monitoring, reviewing and evaluating their needs. The aim of the research was to establish to what extent cooperation between the communities and the ward committees in the ward of New Brighton exists, with specific reference to consultation and participation in terms of IDP. A qualitative study was undertaken and literature review on public participation in terms of the IDP was conducted. Relevant secondary data was sourced and structured interviews were conducted with councillors representing New Brighton. Focus group interviews were also conducted with ward committee members from New Brighton. The research revealed that the priorities and genuine needs of the communities were often ignored by the Nelson Mandela Bay Municipality. There is no correlation between the genuine needs of the communities and those perceived to be the needs of the communities by the public officials. Challenges on public participation in IDP process were also found to be associated with the relationship between the councillors and public officials on what constitute the genuine needs of the communities.
- Full Text:
- Date Issued: 2012
- Authors: Mbewana, Stembiso Matthews
- Date: 2012
- Subjects: Local government -- South Africa -- Port Elizabeth -- Citizen participation , Local governement -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: vital:8178 , http://hdl.handle.net/10948/1775 , Local government -- South Africa -- Port Elizabeth -- Citizen participation , Local governement -- South Africa -- Port Elizabeth
- Description: The most important difference between the new form of local government and that of the past is the creative and dynamic “developmental role” for local government to ensure maximum impact on poverty alleviation within resource constraints, and to address spatially entrenched socio‐economic inequalities. This needs to take place within the framework of integrated development planning, which is linked to the annual budgeting cycles. The IDP process is intended to provide communities with opportunities for participation in articulating, monitoring, reviewing and evaluating their needs. The aim of the research was to establish to what extent cooperation between the communities and the ward committees in the ward of New Brighton exists, with specific reference to consultation and participation in terms of IDP. A qualitative study was undertaken and literature review on public participation in terms of the IDP was conducted. Relevant secondary data was sourced and structured interviews were conducted with councillors representing New Brighton. Focus group interviews were also conducted with ward committee members from New Brighton. The research revealed that the priorities and genuine needs of the communities were often ignored by the Nelson Mandela Bay Municipality. There is no correlation between the genuine needs of the communities and those perceived to be the needs of the communities by the public officials. Challenges on public participation in IDP process were also found to be associated with the relationship between the councillors and public officials on what constitute the genuine needs of the communities.
- Full Text:
- Date Issued: 2012
Winston Leonard Spencer Churchill: a psychobiographical study
- Authors: Moolman, Bilué Anton
- Date: 2012
- Subjects: Churchill, Winston -- 1874-1965 , Psychology -- Biographical methods
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9903 , http://hdl.handle.net/10948/d1009434 , Churchill, Winston -- 1874-1965 , Psychology -- Biographical methods
- Description: Psychobiography is a qualitative approach to exploring and understanding the life story of an individual through the lens of psychological theory. The application of theory is typically conducted on the finished lives of well-known or enigmatic people. This study explores and describes the psychological development across the lifespan of Winston Leonard Spencer Churchill, by applying the Individual Psychology of Alfred Adler. Winston Churchill voted the greatest Briton of the twentieth century, was an author, painter, adventure, soldier, politician and Prime Minister that led the United Kingdom during World War Two. Extensive data has been examined in this work to ensure an accurate description of Winston Churchill‘s life. Alexander‘s model of identifying salient themes was used to analyse the data within a conceptual framework derived from the theory. Churchill‘s difficult childhood motivated him to succeed, his passion for the nation of Britain and his dislike of the Nazi regime meant that Churchill was always abreast with current affairs, anticipating every possible scenario of attack. When the time came to fight the Nazi‘s Churchill was ready to die for his country. The research findings highlight Churchill‘s ability to rise above his childhood stigmas and surpass all expectations and so cementing his name into the history of a country he loved and a democratic world he hoped for. Alfred Adler‘s Individual Psychology proposes that an individual‘s potential weaknesses can be used as a means to strive and achieve greatness within their sphere of influence.
- Full Text:
- Date Issued: 2012
- Authors: Moolman, Bilué Anton
- Date: 2012
- Subjects: Churchill, Winston -- 1874-1965 , Psychology -- Biographical methods
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9903 , http://hdl.handle.net/10948/d1009434 , Churchill, Winston -- 1874-1965 , Psychology -- Biographical methods
- Description: Psychobiography is a qualitative approach to exploring and understanding the life story of an individual through the lens of psychological theory. The application of theory is typically conducted on the finished lives of well-known or enigmatic people. This study explores and describes the psychological development across the lifespan of Winston Leonard Spencer Churchill, by applying the Individual Psychology of Alfred Adler. Winston Churchill voted the greatest Briton of the twentieth century, was an author, painter, adventure, soldier, politician and Prime Minister that led the United Kingdom during World War Two. Extensive data has been examined in this work to ensure an accurate description of Winston Churchill‘s life. Alexander‘s model of identifying salient themes was used to analyse the data within a conceptual framework derived from the theory. Churchill‘s difficult childhood motivated him to succeed, his passion for the nation of Britain and his dislike of the Nazi regime meant that Churchill was always abreast with current affairs, anticipating every possible scenario of attack. When the time came to fight the Nazi‘s Churchill was ready to die for his country. The research findings highlight Churchill‘s ability to rise above his childhood stigmas and surpass all expectations and so cementing his name into the history of a country he loved and a democratic world he hoped for. Alfred Adler‘s Individual Psychology proposes that an individual‘s potential weaknesses can be used as a means to strive and achieve greatness within their sphere of influence.
- Full Text:
- Date Issued: 2012
Evaluation of noise levels of micro-wind turbines using a randomised experiment
- Authors: Clohessy, Chantelle May
- Date: 2012
- Subjects: Wind turbines -- Noise , Wind turbines -- valuation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10508 , http://hdl.handle.net/10948/d1015974
- Description: One of the biggest environmental concerns of a wind turbine is the wind turbine noise (Prospathopoulos and Voutsinas, 2007). This study assesses the noise impacts of wind turbines on the environment by comparing the micro-wind turbine noise to traditional accepted surrounding sounds. The collection of the sound level data was done by using a randomised experiment. The sound level data was then fitted to a General Linear Model to determine the relationship between the sound levels generated at a given site to the time of day, wind speed, wind direction and distance from the sound source. An additional study was conducted to determine the relationship between wind speed and the sound levels of wind turbines. The distribution of frequency components of wind turbine sound was also determined.
- Full Text:
- Date Issued: 2012
- Authors: Clohessy, Chantelle May
- Date: 2012
- Subjects: Wind turbines -- Noise , Wind turbines -- valuation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10508 , http://hdl.handle.net/10948/d1015974
- Description: One of the biggest environmental concerns of a wind turbine is the wind turbine noise (Prospathopoulos and Voutsinas, 2007). This study assesses the noise impacts of wind turbines on the environment by comparing the micro-wind turbine noise to traditional accepted surrounding sounds. The collection of the sound level data was done by using a randomised experiment. The sound level data was then fitted to a General Linear Model to determine the relationship between the sound levels generated at a given site to the time of day, wind speed, wind direction and distance from the sound source. An additional study was conducted to determine the relationship between wind speed and the sound levels of wind turbines. The distribution of frequency components of wind turbine sound was also determined.
- Full Text:
- Date Issued: 2012
Development of molecularly imprinted polymer based solid phase extraction sorbents for the selective cleanup of food and pharmaceutical residue samples
- Authors: Batlokwa, Bareki Shima
- Date: 2012
- Subjects: Sorbents -- Research Nanofibers -- Research Aflatoxins -- Research Electrospinning -- Research Extraction (Chemistry) -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4309 , http://hdl.handle.net/10962/d1004967
- Description: This thesis presents the development of chlorophyll, cholic acid, aflatoxin B1 molecularly imprinted polymer (MIP) particles and cholic acid MIP nanofibers for application as selective solid phase extraction (SPE) sorbents. The particles were prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The AFB1 MIP particles were compared with an aflatoxin specific immunoextraction sorbent in cleaning-up and pre-concentrating aflatoxins from nut extracts. They both recorded high extraction efficiencies (EEs) of > 97 % in selectively extracting the aflatoxins (AFB1, AFB2, AFG1 and AFG2). High reproducibility marked by the low %RSDs of < 1% and low LODs of ≤ 0.02 ng/g were calculated in all cases. The LODs were within the monitoring requirements of the European Commission. The results were validated with a peanut butter certified reference material. The chlorophyll MIP on the other hand selectively removed chlorophyll that would otherwise interfere during pesticide residue analysis (PRA) from > 0.6 to <0.09 Au in green plants extracts. The extracted chlorophyll was removed to far below the level of ≥ 0.399 Au that is usually associated with interference during PRA. Furthermore, the MIP demonstrated better selectivity by removing only chlorophyll (> 99%) in the presence of planar pesticides than the currently employed graphitized carbon black (GCB) that removed both the chlorophyll (> 88%) and planar pesticides (> 89%). For the interfering cholic acid during drug residue analysis, cholic acid MIP electrospun nanofibers demonstrated to be more sensitive and possessing higher loading capacity than the MIP particles. 100% cholic acid was removed by the nanofibers from standard solutions relative to 80% by the particles. This showed that the nanofibers have better performance than the micro particles and as such have potential to replace the particle based SPE sorbents that are currently in use. All the templates were optimally removed from the prepared MIPs by employing a novel pressurized hot water extraction template removal method that was used for the first time in this thesis. The method employed only water, an environmentally friendly solvent to remove templates to ≥ 99.6% with template residual bleeding of ≤ 0.02%.
- Full Text:
- Date Issued: 2012
- Authors: Batlokwa, Bareki Shima
- Date: 2012
- Subjects: Sorbents -- Research Nanofibers -- Research Aflatoxins -- Research Electrospinning -- Research Extraction (Chemistry) -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4309 , http://hdl.handle.net/10962/d1004967
- Description: This thesis presents the development of chlorophyll, cholic acid, aflatoxin B1 molecularly imprinted polymer (MIP) particles and cholic acid MIP nanofibers for application as selective solid phase extraction (SPE) sorbents. The particles were prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The AFB1 MIP particles were compared with an aflatoxin specific immunoextraction sorbent in cleaning-up and pre-concentrating aflatoxins from nut extracts. They both recorded high extraction efficiencies (EEs) of > 97 % in selectively extracting the aflatoxins (AFB1, AFB2, AFG1 and AFG2). High reproducibility marked by the low %RSDs of < 1% and low LODs of ≤ 0.02 ng/g were calculated in all cases. The LODs were within the monitoring requirements of the European Commission. The results were validated with a peanut butter certified reference material. The chlorophyll MIP on the other hand selectively removed chlorophyll that would otherwise interfere during pesticide residue analysis (PRA) from > 0.6 to <0.09 Au in green plants extracts. The extracted chlorophyll was removed to far below the level of ≥ 0.399 Au that is usually associated with interference during PRA. Furthermore, the MIP demonstrated better selectivity by removing only chlorophyll (> 99%) in the presence of planar pesticides than the currently employed graphitized carbon black (GCB) that removed both the chlorophyll (> 88%) and planar pesticides (> 89%). For the interfering cholic acid during drug residue analysis, cholic acid MIP electrospun nanofibers demonstrated to be more sensitive and possessing higher loading capacity than the MIP particles. 100% cholic acid was removed by the nanofibers from standard solutions relative to 80% by the particles. This showed that the nanofibers have better performance than the micro particles and as such have potential to replace the particle based SPE sorbents that are currently in use. All the templates were optimally removed from the prepared MIPs by employing a novel pressurized hot water extraction template removal method that was used for the first time in this thesis. The method employed only water, an environmentally friendly solvent to remove templates to ≥ 99.6% with template residual bleeding of ≤ 0.02%.
- Full Text:
- Date Issued: 2012