The influence of electronic-consumer experience (e-CX) on consumer post-purchase outcomes of South African e-commerce retail organisations
- Authors: Williams, Alyssa Shawntay
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/434828 , vital:73108
- Description: Access restricted. Expected release in 2026. , Thesis (PhD) -- Faculty of Commerce, Management, 2024
- Full Text:
- Date Issued: 2024-04-03
- Authors: Williams, Alyssa Shawntay
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/434828 , vital:73108
- Description: Access restricted. Expected release in 2026. , Thesis (PhD) -- Faculty of Commerce, Management, 2024
- Full Text:
- Date Issued: 2024-04-03
The influence of strategic leadership on the performance of small and medium-sized enterprises as mediated by strategy implementation
- Authors: January, Nceba
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434723 , vital:73099
- Description: Small and medium-sized enterprises (SMEs) are viewed as the cornerstone of socio-economic development in many economies globally. The progressive contribution of SMEs to the global economy is irrefutable and enshrined in poverty alleviation, inclusive economic growth, and job creation strategies pursued by many economies worldwide. SMEs are primarily the form of enterprise that accounts for over 90% of all businesses; thus, Small and Medium-sized Enterprises are the main source of employment. SMEs' contribution to value creation is estimated to be above 50% on average. In emerging countries, particularly South Africa, SMEs contribute approximately 45% of the total employment and 33% of the Gross Domestic Product (GDP). In most countries, Small and Medium-sized Enterprises contribute to more than 50% of employment and GDP, and these figures become significantly higher when the informal small business sector is included. World Bank estimated 600 million jobs needed by 2030, making SME development a high priority for many governments worldwide. Despite globally acknowledged SME contributions, small businesses are still faced with many challenges that have ramifications on their survival, growth, and performance. Studies highlighted challenges such as lack of access to finance and funding modalities, appropriate technology and infrastructure, markets and social networks, and lack of research and development, strategic management skills, and inability to perform managerial tasks, among others. Recent studies have been conducted on many of these challenges; however, there is little known about the strategic management challenges that face SMEs and their business performance. Several studies were conducted on some of these strategic management challenges, such as strategic planning, strategic orientation, strategic agility, organisational flexibility, and total quality management. However, a review of studies relevant to SMEs and their performance is silent on the argument regarding the influence of strategic leadership on the performance of SMEs, especially when key drivers of effective strategy implementation mediate strategic leadership. Thus, this study investigated the influence of strategic leadership on the performance of SMEs as mediated by strategy implementation in Nelson Mandela Bay (NMB). A detailed theoretical investigation was conducted on the nature and role of strategic leadership, strategy implementation, and business performance of SMEs. Strategic leadership represents the independent variables of this study, namely: strategic direction, balanced organisational controls, organisational culture, organisation’s resource portfolio, and ethical practice, followed by the mediating variable (strategy implementation) and the dependent variable (business performance). An empirical investigation was also conducted to test the significant influence between these variables. This study adopted a positivistic approach using a quantitative research method. The sample size of the study was 390 respondents. Self-developed and structured questionnaires were physically distributed to 315 SME owners and managers in NMB using a convenience sampling method. Only 229 returned questionnaires were suitable and relevant to this study; thus, a 72.69% response rate was achieved. Returned questionnaires were cleansed, coded, and transferred to a statistical data analysis software called Statistica, version 14.0, for quantitative data analyses. The validity and reliability of the measuring instrument were confirmed using Exploratory Factor Analysis and the calculation of Cronbach’s alpha coefficients. Descriptive statistics was calculated to summarise the empirical data on demographic variables and the main variables of this study. Pearson’s correlations were calculated to determine the correlations between the main variables of this study, and the results confirmed that there is a positive influence between strategic leadership, strategy implementation, and business performance of SMEs. A multiple linear regression analysis was conducted to test the significance of the influence between the main variables of the study. A regression analysis outcome revealed that some of the strategic leadership activities (strategic direction, balanced organisational controls, and organisational culture) have a statistically significant positive influence on the business performance of SMEs. Furthermore, a statistically significant positive influence does exist between strategy implementation and business performance of SMEs. This study’s recommendations were suggested to SME owners/managers. Firstly, to formulate and develop a clear long-term vision of the business for the next 3 to 5 years. Align resources to key areas of business operation and set internal controls that will help set standards of desired performance and ultimately achieve them. Secondly, to formulate and implement shared values that connect employees to the business purpose and the way it is conducted. These shared values must be underpinned by a unique, valuable, and incomparable culture against competitors to gain a competitive edge. Furthermore, consider using rewards to recognise employees who embody the shared values of the business and are committed to the success of the business because of its culture. Thirdly, ensure both strategic and financial controls support strategy implementation and guide employees to achieve performance objectives. Use balanced scorecards to assess the effectiveness of controls in the business and put corrective measures to address performance gaps. Last but not least, invest in staff development and training, technological infrastructure, and set sound processes and systems for the business operation, establish structures that have clear lines of reporting, authority, and delegation. , Thesis (MCom) -- Faculty of Commerce, Management, 2024
- Full Text:
- Date Issued: 2024-04-03
- Authors: January, Nceba
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434723 , vital:73099
- Description: Small and medium-sized enterprises (SMEs) are viewed as the cornerstone of socio-economic development in many economies globally. The progressive contribution of SMEs to the global economy is irrefutable and enshrined in poverty alleviation, inclusive economic growth, and job creation strategies pursued by many economies worldwide. SMEs are primarily the form of enterprise that accounts for over 90% of all businesses; thus, Small and Medium-sized Enterprises are the main source of employment. SMEs' contribution to value creation is estimated to be above 50% on average. In emerging countries, particularly South Africa, SMEs contribute approximately 45% of the total employment and 33% of the Gross Domestic Product (GDP). In most countries, Small and Medium-sized Enterprises contribute to more than 50% of employment and GDP, and these figures become significantly higher when the informal small business sector is included. World Bank estimated 600 million jobs needed by 2030, making SME development a high priority for many governments worldwide. Despite globally acknowledged SME contributions, small businesses are still faced with many challenges that have ramifications on their survival, growth, and performance. Studies highlighted challenges such as lack of access to finance and funding modalities, appropriate technology and infrastructure, markets and social networks, and lack of research and development, strategic management skills, and inability to perform managerial tasks, among others. Recent studies have been conducted on many of these challenges; however, there is little known about the strategic management challenges that face SMEs and their business performance. Several studies were conducted on some of these strategic management challenges, such as strategic planning, strategic orientation, strategic agility, organisational flexibility, and total quality management. However, a review of studies relevant to SMEs and their performance is silent on the argument regarding the influence of strategic leadership on the performance of SMEs, especially when key drivers of effective strategy implementation mediate strategic leadership. Thus, this study investigated the influence of strategic leadership on the performance of SMEs as mediated by strategy implementation in Nelson Mandela Bay (NMB). A detailed theoretical investigation was conducted on the nature and role of strategic leadership, strategy implementation, and business performance of SMEs. Strategic leadership represents the independent variables of this study, namely: strategic direction, balanced organisational controls, organisational culture, organisation’s resource portfolio, and ethical practice, followed by the mediating variable (strategy implementation) and the dependent variable (business performance). An empirical investigation was also conducted to test the significant influence between these variables. This study adopted a positivistic approach using a quantitative research method. The sample size of the study was 390 respondents. Self-developed and structured questionnaires were physically distributed to 315 SME owners and managers in NMB using a convenience sampling method. Only 229 returned questionnaires were suitable and relevant to this study; thus, a 72.69% response rate was achieved. Returned questionnaires were cleansed, coded, and transferred to a statistical data analysis software called Statistica, version 14.0, for quantitative data analyses. The validity and reliability of the measuring instrument were confirmed using Exploratory Factor Analysis and the calculation of Cronbach’s alpha coefficients. Descriptive statistics was calculated to summarise the empirical data on demographic variables and the main variables of this study. Pearson’s correlations were calculated to determine the correlations between the main variables of this study, and the results confirmed that there is a positive influence between strategic leadership, strategy implementation, and business performance of SMEs. A multiple linear regression analysis was conducted to test the significance of the influence between the main variables of the study. A regression analysis outcome revealed that some of the strategic leadership activities (strategic direction, balanced organisational controls, and organisational culture) have a statistically significant positive influence on the business performance of SMEs. Furthermore, a statistically significant positive influence does exist between strategy implementation and business performance of SMEs. This study’s recommendations were suggested to SME owners/managers. Firstly, to formulate and develop a clear long-term vision of the business for the next 3 to 5 years. Align resources to key areas of business operation and set internal controls that will help set standards of desired performance and ultimately achieve them. Secondly, to formulate and implement shared values that connect employees to the business purpose and the way it is conducted. These shared values must be underpinned by a unique, valuable, and incomparable culture against competitors to gain a competitive edge. Furthermore, consider using rewards to recognise employees who embody the shared values of the business and are committed to the success of the business because of its culture. Thirdly, ensure both strategic and financial controls support strategy implementation and guide employees to achieve performance objectives. Use balanced scorecards to assess the effectiveness of controls in the business and put corrective measures to address performance gaps. Last but not least, invest in staff development and training, technological infrastructure, and set sound processes and systems for the business operation, establish structures that have clear lines of reporting, authority, and delegation. , Thesis (MCom) -- Faculty of Commerce, Management, 2024
- Full Text:
- Date Issued: 2024-04-03
The private collection: aura, the cult of celebrity and, the construct of value in saleable works of art
- Authors: Ellis, Yvette Tamsin
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434574 , vital:73086
- Description: A tenet of the twenty-first century is the monetisation of everything due to commercialisation. The effects of this commercialisation have crept into every aspect of our lives, and although in the art world it has mostly been underhanded in its adoption, the traces of commercialisations touch are still evident in its functioning. Due to this underhandedness there hasn't been much thought put into what 'the monetisation of everything' truly implies for the industry, or how the value of the art object devoted to commercialisation may look like. The Private Collection (exhibition title of the practical component for submission in MFA completion) addresses the concept of object value and, more specifically, how that value is created within the art world through mechanisms of commercialisation that include celebrity cult, functioning of possession (through collecting), and taste. Research into Walter Benjamin's theory of the authenticity of the work of art, and in particular his concept of "aura," has helped inform the creation of a marketing strategy propelled by value driven mechanisms found within the Art Market for The Private Collection. Particular emphasis is placed on how brand value drives sales in this thesis. Thus, The Private Collection: Aura, the Cult of Celebrity, and the Construct of Value in Saleable Works of Art, defines The Private Collection as a tailored system built expressly for engagement with economic forces inside the art industry. As a result, the position of this study is based on the marketability of the object through particular driving forces that have seeped into the value system of the saleable work of art. The position of this thesis is that in this commercialist system, driving forces of value can be sustained within instances of the multiple. The project additionally supports this in maintaining that interaction from a fine art perspective would be limited if restricted to orthodox approaches (a gallery showing, and one print works), which is why a more economically interactive approach (e-commerce) was decided on for the exhibition component. The Private Collection offers an observation that the worth of a saleable work of art has become a warped representation of the commercial context we find ourselves in and that value is only awarded through particular kingmakers of the system. The practical component of this submission can be viewed online by clicking the image below. Please note that the website is not optimised for phone or tablet use, please instead view it on a computer (preferably a desktop) in full screen mode. , Thesis (MFA) -- Faculty of Humanities, Fine Art, 2024
- Full Text:
- Date Issued: 2024-04-03
- Authors: Ellis, Yvette Tamsin
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434574 , vital:73086
- Description: A tenet of the twenty-first century is the monetisation of everything due to commercialisation. The effects of this commercialisation have crept into every aspect of our lives, and although in the art world it has mostly been underhanded in its adoption, the traces of commercialisations touch are still evident in its functioning. Due to this underhandedness there hasn't been much thought put into what 'the monetisation of everything' truly implies for the industry, or how the value of the art object devoted to commercialisation may look like. The Private Collection (exhibition title of the practical component for submission in MFA completion) addresses the concept of object value and, more specifically, how that value is created within the art world through mechanisms of commercialisation that include celebrity cult, functioning of possession (through collecting), and taste. Research into Walter Benjamin's theory of the authenticity of the work of art, and in particular his concept of "aura," has helped inform the creation of a marketing strategy propelled by value driven mechanisms found within the Art Market for The Private Collection. Particular emphasis is placed on how brand value drives sales in this thesis. Thus, The Private Collection: Aura, the Cult of Celebrity, and the Construct of Value in Saleable Works of Art, defines The Private Collection as a tailored system built expressly for engagement with economic forces inside the art industry. As a result, the position of this study is based on the marketability of the object through particular driving forces that have seeped into the value system of the saleable work of art. The position of this thesis is that in this commercialist system, driving forces of value can be sustained within instances of the multiple. The project additionally supports this in maintaining that interaction from a fine art perspective would be limited if restricted to orthodox approaches (a gallery showing, and one print works), which is why a more economically interactive approach (e-commerce) was decided on for the exhibition component. The Private Collection offers an observation that the worth of a saleable work of art has become a warped representation of the commercial context we find ourselves in and that value is only awarded through particular kingmakers of the system. The practical component of this submission can be viewed online by clicking the image below. Please note that the website is not optimised for phone or tablet use, please instead view it on a computer (preferably a desktop) in full screen mode. , Thesis (MFA) -- Faculty of Humanities, Fine Art, 2024
- Full Text:
- Date Issued: 2024-04-03
The relationship between Environmental, Social, Governance (ESG) and Corporate Financial Performance (CFP)
- Authors: Bendeman, Justin John
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434701 , vital:73097
- Description: Restricted access. Expected release date 2025. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2024
- Full Text:
- Date Issued: 2024-04-03
- Authors: Bendeman, Justin John
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434701 , vital:73097
- Description: Restricted access. Expected release date 2025. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2024
- Full Text:
- Date Issued: 2024-04-03
The relationship between leadership and employee engagement in an automotive original equipment manufacturer in South Africa
- Authors: Slater, Bronwyn Lereen
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434756 , vital:73102
- Description: The manufacturing industry is one of the greatest contributors to the South African economy. Owing to a competitive and complex automotive climate, it is suggested that only a few automotive manufacturing organisations will remain viable in the coming years, without the optimal reliance on human capital resources to navigate an unpredictable and unfolding landscape. In securing a sustainable future, the engagement of these human capital resources is necessitated. This competitive landscape has resulted in the call for adaptive and flexible leadership. Leadership behaviour is categorised into three streams, namely, transformational leadership, transactional leadership, and non-leadership, which is referred to as laissez-faire leadership. Employee engagement is defined as the extent to which an employee is committed to, and involved in, their operational function and the organisation, whilst portraying a willingness to perform and contribute beyond that which is expected of them. The purpose of this research was to explore the relationship between leadership and employee engagement in an Original Equipment Manufacturer (OEM) in South Africa. This OEM operates in the Eastern Cape and Gauteng Provinces of South Africa. Globally, the OEM launched a leadership journey to facilitate a shared value system that supported a vision towards organisational success, by focusing on transformed ways of working and acting, as a global collective team. The outcome of this desired journey yielded eight Leadership Principles. These Leadership Principles are referred to, and included in the research study, to gain a more robust internal perspective of the leadership behaviours that are most advocated within the OEM, in relation to employee engagement. The objective of this research therefore was to establish the relationship between leadership and employee engagement in the respective OEM, by investigating the impact of transformational leadership and transactional leadership on employee engagement. A triangulation approach was adopted to analyse the data, using a combination of qualitative and quantitative research methodologies. The result when testing the reliability coefficient scores of the leadership instrument described a poor measure for transactional leadership, and a good measure for transformational leadership. Therefore, the results that stemmed from the statistical analysis in relation to transactional leadership could not be trusted. However, in the context of this research, it was found that there is a statistically significant relationship between transformational leadership and employee engagement. Whilst utilising the qualitative research methodology, it was found that there is a limited definition-based relationship between transactional leadership and the eight Leadership Principles. However, there is a definition-based relationship between the Leadership Principles and transformational leadership, owing to similarities found in the definition descriptions between at least six of the eight Leadership Principles. In the investigation of whether there is a definition-based relationship between the Leadership Principles and employee engagement, it was found that a limited definition-based relationship between the eight Leadership Principles and engagement existed. The research therefore met its objectives in determining a relationship between leadership and employee engagement in an Original Equipment Manufacturer in South Africa. , Thesis (MCom) -- Faculty of Commerce, Management, 2024
- Full Text:
- Date Issued: 2024-04-03
- Authors: Slater, Bronwyn Lereen
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434756 , vital:73102
- Description: The manufacturing industry is one of the greatest contributors to the South African economy. Owing to a competitive and complex automotive climate, it is suggested that only a few automotive manufacturing organisations will remain viable in the coming years, without the optimal reliance on human capital resources to navigate an unpredictable and unfolding landscape. In securing a sustainable future, the engagement of these human capital resources is necessitated. This competitive landscape has resulted in the call for adaptive and flexible leadership. Leadership behaviour is categorised into three streams, namely, transformational leadership, transactional leadership, and non-leadership, which is referred to as laissez-faire leadership. Employee engagement is defined as the extent to which an employee is committed to, and involved in, their operational function and the organisation, whilst portraying a willingness to perform and contribute beyond that which is expected of them. The purpose of this research was to explore the relationship between leadership and employee engagement in an Original Equipment Manufacturer (OEM) in South Africa. This OEM operates in the Eastern Cape and Gauteng Provinces of South Africa. Globally, the OEM launched a leadership journey to facilitate a shared value system that supported a vision towards organisational success, by focusing on transformed ways of working and acting, as a global collective team. The outcome of this desired journey yielded eight Leadership Principles. These Leadership Principles are referred to, and included in the research study, to gain a more robust internal perspective of the leadership behaviours that are most advocated within the OEM, in relation to employee engagement. The objective of this research therefore was to establish the relationship between leadership and employee engagement in the respective OEM, by investigating the impact of transformational leadership and transactional leadership on employee engagement. A triangulation approach was adopted to analyse the data, using a combination of qualitative and quantitative research methodologies. The result when testing the reliability coefficient scores of the leadership instrument described a poor measure for transactional leadership, and a good measure for transformational leadership. Therefore, the results that stemmed from the statistical analysis in relation to transactional leadership could not be trusted. However, in the context of this research, it was found that there is a statistically significant relationship between transformational leadership and employee engagement. Whilst utilising the qualitative research methodology, it was found that there is a limited definition-based relationship between transactional leadership and the eight Leadership Principles. However, there is a definition-based relationship between the Leadership Principles and transformational leadership, owing to similarities found in the definition descriptions between at least six of the eight Leadership Principles. In the investigation of whether there is a definition-based relationship between the Leadership Principles and employee engagement, it was found that a limited definition-based relationship between the eight Leadership Principles and engagement existed. The research therefore met its objectives in determining a relationship between leadership and employee engagement in an Original Equipment Manufacturer in South Africa. , Thesis (MCom) -- Faculty of Commerce, Management, 2024
- Full Text:
- Date Issued: 2024-04-03
The Zimbabwe National Gender Policy (NGP) 2013–2017 and Women’s Economic Empowerment (WEE): a study of small-scale gold miners in the Bubi and Gwanda rural districts, Zimbabwe
- Moyo, Phoebe Michelle Zibusiso Sandi
- Authors: Moyo, Phoebe Michelle Zibusiso Sandi
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/434638 , vital:73092 , DOI 10.21504/10962/434638
- Description: The study examines the impact of Zimbabwe’s second National Gender Policy (NGP) 2013-2017 under the Ministry of Women’s Affairs, Gender and Community Development on women’s access to and control over productive resources in the artisanal and small-scale gold mining sector in Bubi and Gwanda rural districts of Zimbabwe. Despite the implementation of the NGP over the past fourteen years, its effect on the economic empowerment of women has not been investigated adequately. Women’s economic empowerment (WEE) is recognized as a crucial development strategy. However, it faces challenges related to the tensions between structure and agency. Some perceive WEE as an entrepreneurial concept focusing on equal access and control over productive resources like credit, equipment, skills, and business training. Others argue that WEE should encompass more than just resource access and control by addressing structural factors that hinder women’s agency e.g. unequal social relations between men and women, patriarchy, unpaid care work, and sociocultural norms. The study employed a hybrid lens, combining structure and agency to analyse the implementation of the NGP’s empowerment programs. Drawing on Kabeer’s (1994) Social Relations Approach (SRA), the study utilized two key concepts from the SRA, namely social relations and institutional analysis, to examine the interaction between the NGP and various institutions (market, community, and family) where women are located. To gain a comprehensive understanding of the ways in which the NGP has supported or impeded WEE among the female small-scale gold miners in Bubi and Gwanda, a qualitative approach was employed as an investigative method. The findings indicated that the NGP adopts a liberal or agency centred approach to WEE. This approach emphasizes women’s agency and their ability to fulfil their potential in the public sphere. The NGP has facilitated access to credit, equipment, skills, and business training. However, the evidence also highlighted the uneven implementation of the NGP’s empowerment programs between the Bubi and Gwanda districts. Overall, the evidence revealed that, while the NGP has addressed gender inequalities to a limited degree, it has also reinforced class inequalities. The NGP’s empowerment programs have overlooked the structural factors that keep women in subordinate positions, such as the unequal social relations that exist between men and women, patriarchy, unpaid care work and sociocultural norms. , Thesis (PhD) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-04-03
- Authors: Moyo, Phoebe Michelle Zibusiso Sandi
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/434638 , vital:73092 , DOI 10.21504/10962/434638
- Description: The study examines the impact of Zimbabwe’s second National Gender Policy (NGP) 2013-2017 under the Ministry of Women’s Affairs, Gender and Community Development on women’s access to and control over productive resources in the artisanal and small-scale gold mining sector in Bubi and Gwanda rural districts of Zimbabwe. Despite the implementation of the NGP over the past fourteen years, its effect on the economic empowerment of women has not been investigated adequately. Women’s economic empowerment (WEE) is recognized as a crucial development strategy. However, it faces challenges related to the tensions between structure and agency. Some perceive WEE as an entrepreneurial concept focusing on equal access and control over productive resources like credit, equipment, skills, and business training. Others argue that WEE should encompass more than just resource access and control by addressing structural factors that hinder women’s agency e.g. unequal social relations between men and women, patriarchy, unpaid care work, and sociocultural norms. The study employed a hybrid lens, combining structure and agency to analyse the implementation of the NGP’s empowerment programs. Drawing on Kabeer’s (1994) Social Relations Approach (SRA), the study utilized two key concepts from the SRA, namely social relations and institutional analysis, to examine the interaction between the NGP and various institutions (market, community, and family) where women are located. To gain a comprehensive understanding of the ways in which the NGP has supported or impeded WEE among the female small-scale gold miners in Bubi and Gwanda, a qualitative approach was employed as an investigative method. The findings indicated that the NGP adopts a liberal or agency centred approach to WEE. This approach emphasizes women’s agency and their ability to fulfil their potential in the public sphere. The NGP has facilitated access to credit, equipment, skills, and business training. However, the evidence also highlighted the uneven implementation of the NGP’s empowerment programs between the Bubi and Gwanda districts. Overall, the evidence revealed that, while the NGP has addressed gender inequalities to a limited degree, it has also reinforced class inequalities. The NGP’s empowerment programs have overlooked the structural factors that keep women in subordinate positions, such as the unequal social relations that exist between men and women, patriarchy, unpaid care work and sociocultural norms. , Thesis (PhD) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-04-03
Tradition and change in the Imfene dance of the amaMpondo in the Ntabankulu district of the Eastern Cape province
- Authors: Mtsini, Nontuthuzelo
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434791 , vital:73105
- Description: Access restricted. Expected release 2025. , Thesis (MMus) -- Faculty of Humanities, Music and Musicology, 2024
- Full Text:
- Date Issued: 2024-04-03
- Authors: Mtsini, Nontuthuzelo
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434791 , vital:73105
- Description: Access restricted. Expected release 2025. , Thesis (MMus) -- Faculty of Humanities, Music and Musicology, 2024
- Full Text:
- Date Issued: 2024-04-03
Yield curve and business cycle dynamics in South Africa: new evidence from a Markov switching model
- Authors: Rotich, Mercyline Chepkemoi
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434739 , vital:73101
- Description: Globally, several empirical studies have demonstrated the ability of the yield spread to predict a recession in a country. In South Africa, previous studies have not only shown the yield curve's predictive power but have further demonstrated that it outperforms other commonly used variables, such as the growth rate of real money supply, changes in stock prices, and the index of leading economic indicators. However, some recent studies have shown that the yield spread (the spread between 10-year bonds and 3-month Treasury bills) gave false signals of recession. In this study, we explore the possible reasons for the false signals of the yield spread by addressing the following questions. Does the yield spread used matter? Does the measure of the business cycle used matter? And do the estimation techniques used matter? To address the first question, unlike the previous studies, this paper uses four different yield spreads- depicting short-term, medium-term, and long-term government bonds against the backdrop of a changing structure of bond holding, which reflects the increasing risk eversion of investors in South Africa. Second, the paper used different measures of business cycles, namely industrial production index, lagging, coincident, and leading economic indicators. The empirical models were estimated using both univariate and multivariate Markov switching models. As economic theory suggests, the univariate Markov switching model was used to determine if each variable exhibits a significant regime switching. The multivariate Markov switching model was estimated for each business cycle and yield spread variable, with each of the other variables serving as a non-switching explanatory variable, thereby addressing potential endogeneity concerns and the predictive power of the explanatory variable. Finally, the multivariate Markov switching model was estimated for three monthly sample periods, a full sample for 1986 to 2022, and two sub-samples – 1986 to 2009 and 2010 to 2022. This analysis consistently reveals significant regime-switching behavior across all the series thus, affirming the superiority of the regime switching model over the standard model used in previous studies. By analyzing the transition probabilities and the expected durations between these regimes, we find that including the spreads in the business cycle model improves the models’ predictability, with the medium-term bonds spread performing better than the usual long-term spread. The smoothed regime probability of the best-performing models is compared with the SARB recession dates; the two closely resemble each other, proving that the Markov switching model can help predict the turning points in the business cycle in South Africa. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2024
- Full Text:
- Date Issued: 2024-04-03
- Authors: Rotich, Mercyline Chepkemoi
- Date: 2024-04-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434739 , vital:73101
- Description: Globally, several empirical studies have demonstrated the ability of the yield spread to predict a recession in a country. In South Africa, previous studies have not only shown the yield curve's predictive power but have further demonstrated that it outperforms other commonly used variables, such as the growth rate of real money supply, changes in stock prices, and the index of leading economic indicators. However, some recent studies have shown that the yield spread (the spread between 10-year bonds and 3-month Treasury bills) gave false signals of recession. In this study, we explore the possible reasons for the false signals of the yield spread by addressing the following questions. Does the yield spread used matter? Does the measure of the business cycle used matter? And do the estimation techniques used matter? To address the first question, unlike the previous studies, this paper uses four different yield spreads- depicting short-term, medium-term, and long-term government bonds against the backdrop of a changing structure of bond holding, which reflects the increasing risk eversion of investors in South Africa. Second, the paper used different measures of business cycles, namely industrial production index, lagging, coincident, and leading economic indicators. The empirical models were estimated using both univariate and multivariate Markov switching models. As economic theory suggests, the univariate Markov switching model was used to determine if each variable exhibits a significant regime switching. The multivariate Markov switching model was estimated for each business cycle and yield spread variable, with each of the other variables serving as a non-switching explanatory variable, thereby addressing potential endogeneity concerns and the predictive power of the explanatory variable. Finally, the multivariate Markov switching model was estimated for three monthly sample periods, a full sample for 1986 to 2022, and two sub-samples – 1986 to 2009 and 2010 to 2022. This analysis consistently reveals significant regime-switching behavior across all the series thus, affirming the superiority of the regime switching model over the standard model used in previous studies. By analyzing the transition probabilities and the expected durations between these regimes, we find that including the spreads in the business cycle model improves the models’ predictability, with the medium-term bonds spread performing better than the usual long-term spread. The smoothed regime probability of the best-performing models is compared with the SARB recession dates; the two closely resemble each other, proving that the Markov switching model can help predict the turning points in the business cycle in South Africa. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2024
- Full Text:
- Date Issued: 2024-04-03
Assessing rural senior primary school natural science teachers’ TPACK: a case study
- Authors: Silvanus, Secilia Tulikefo
- Date: 2024-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/423902 , vital:72103
- Description: In today's world, technology has changed how people live and behave. The influence of technology contemplates a similar change in the education processes of teaching and learning. Many governments worldwide invest hugely in providing technological tools and facilities and training teachers to improve teaching and learning. The availability and access to technologies in schools seem to offer teachers opportunities to develop technological knowledge and integrate technology into teaching. Literature indicates that teachers must possess technological pedagogical content knowledge (TPACK) to integrate technology into teaching and learning processes effectively. However, other scholars have also suggested that teachers' TPACK develops and is shaped by many contexts. This study, therefore, sought to assess the rural senior primary Natural science teachers' TPACK. This qualitative case study was conducted with senior primary Natural science teachers in the educational circuit of Endola. An interpretive paradigm underpinned the study. The study employed semi-structured questionnaires, semi-structured interviews, focus group interviews, and observation to collect the data. The study used the TPACK as a theoretical and analytical framework. The study results showed that participants had a firmer grasp of subject content (CK) and traditional teaching methods (Pedagogical Knowledge - PK and Pedagogical Content Knowledge - PCK) compared to technological knowledge (TK) and technology-based pedagogies (Technological Pedagogical Knowledge - TPK, Technological Content Knowledge - TCK, and Technological Pedagogical Content Knowledge (TPCK). Findings support that the participants draw upon sources of Technological Pedagogical Content Knowledge (TPACK) closely aligned with Content Knowledge (CK), Technological Content Knowledge (TCK), and Technological Pedagogical Knowledge (TPK) to integrate technology. The study included inadequate professional development, teachers' attitudes, insufficient hardware and internet connectivity, limited technological knowledge, time constraints, and restricted access to technology tools and resources as obstacles for teachers attempting to incorporate technology into their classrooms effectively. Furthermore, the data highlights ICT training and teachers' interest as enablers that motivated participants to integrate technology into their teaching practices. Therefore, the study recommends professional development programs focusing on providing science teachers with practical skills to utilise different technologies and address common technical issues. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text:
- Date Issued: 2024-04
- Authors: Silvanus, Secilia Tulikefo
- Date: 2024-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/423902 , vital:72103
- Description: In today's world, technology has changed how people live and behave. The influence of technology contemplates a similar change in the education processes of teaching and learning. Many governments worldwide invest hugely in providing technological tools and facilities and training teachers to improve teaching and learning. The availability and access to technologies in schools seem to offer teachers opportunities to develop technological knowledge and integrate technology into teaching. Literature indicates that teachers must possess technological pedagogical content knowledge (TPACK) to integrate technology into teaching and learning processes effectively. However, other scholars have also suggested that teachers' TPACK develops and is shaped by many contexts. This study, therefore, sought to assess the rural senior primary Natural science teachers' TPACK. This qualitative case study was conducted with senior primary Natural science teachers in the educational circuit of Endola. An interpretive paradigm underpinned the study. The study employed semi-structured questionnaires, semi-structured interviews, focus group interviews, and observation to collect the data. The study used the TPACK as a theoretical and analytical framework. The study results showed that participants had a firmer grasp of subject content (CK) and traditional teaching methods (Pedagogical Knowledge - PK and Pedagogical Content Knowledge - PCK) compared to technological knowledge (TK) and technology-based pedagogies (Technological Pedagogical Knowledge - TPK, Technological Content Knowledge - TCK, and Technological Pedagogical Content Knowledge (TPCK). Findings support that the participants draw upon sources of Technological Pedagogical Content Knowledge (TPACK) closely aligned with Content Knowledge (CK), Technological Content Knowledge (TCK), and Technological Pedagogical Knowledge (TPK) to integrate technology. The study included inadequate professional development, teachers' attitudes, insufficient hardware and internet connectivity, limited technological knowledge, time constraints, and restricted access to technology tools and resources as obstacles for teachers attempting to incorporate technology into their classrooms effectively. Furthermore, the data highlights ICT training and teachers' interest as enablers that motivated participants to integrate technology into their teaching practices. Therefore, the study recommends professional development programs focusing on providing science teachers with practical skills to utilise different technologies and address common technical issues. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text:
- Date Issued: 2024-04
Technological Pedagogical Content Knowledge (TPACK): investigating senior primary mathematics teachers’ integration of technology in the classroom in Okahao educational circuit
- Shikesho, Hilya Ndahambelela
- Authors: Shikesho, Hilya Ndahambelela
- Date: 2024-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/423913 , vital:72104
- Description: Access restricted. Expected release date 2025. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text:
- Date Issued: 2024-04
- Authors: Shikesho, Hilya Ndahambelela
- Date: 2024-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/423913 , vital:72104
- Description: Access restricted. Expected release date 2025. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text:
- Date Issued: 2024-04
Systematic effects and mitigation strategies in observations of cosmic re-ionisation with the Hydrogen Epoch of Reionization Array
- Authors: Charles, Ntsikelelo
- Date: 2024
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432605 , vital:72886 , DOI 10.21504/10962/432605
- Description: The 21 cm transition from neutral Hydrogen promises to be the best observational probe of the Epoch of Reionisation (EoR). It has driven the construction of the new generation of lowfrequency radio interferometric arrays, including the Hydrogen Epoch of Reionization Array (HERA). The main difficulty in measuring the 21 cm signal is the presence of bright foregrounds that require very accurate interferometric calibration. However, the non-smooth instrumental response of the antenna as a result of mutual coupling complicates the calibration process by introducing non-smooth calibration errors. Additionally, incomplete sky models are typically used in calibration due to the limited depth and resolution of current source catalogues. Combined with the instrumental response, the use of incomplete sky models during calibration can result in non-smooth calibration errors. These, overall, impart spectral structure on smooth foregrounds, leading to foreground power leakage into the EoR window. In this thesis we explored the use of fringe rate filters (Parsons et al., 2016) as a mean to mitigate calibration errors resulting from the effects of mutual coupling and the use of an incomplete sky model during calibration. We found that the use of a simple notch filter mitigates calibration errors reducing the foreground power leakage into the EoR window by a factor of ∼ 102. Thyagarajan et al. (2018) proposed the use of closure phase quantities as a means to detect the 21 cm signal, which has the advantage of being independent (to first order) from calibration errors and, therefore, bypasses the need for accurate calibration. In this thesis, we explore the impact of primary beam patterns affected by mutual coupling on the closure phase. We found that primary beams affected by mutual coupling lead to a leakage of foreground power into the EoR window, which can be up to ∼ 104 times and is mainly caused by the unsmooth spectral structure primary of primary beam sidelobes affected by mutual coupling. This power leakage was confined to k < 0.3 pseudo h Mpc−1. Lastly, we also proposed and demonstrated an analysis technique that can be used to derive a flux scale correction in post-calibrated HERA data. We found that after applying flux scale correction to calibrated HERA data, the bandpass error reduces significantly, with an improvement of 6%. The derived flux scale correction was antenna-independent, and it can be applied to fix the overall visibility spectrum scale of H4C data post-calibration in a fashion similar to Jacobs et al. (2013). , Thesis (PhD) -- Faculty of Science, Physics and Electronics, 2024
- Full Text:
- Date Issued: 2024
- Authors: Charles, Ntsikelelo
- Date: 2024
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432605 , vital:72886 , DOI 10.21504/10962/432605
- Description: The 21 cm transition from neutral Hydrogen promises to be the best observational probe of the Epoch of Reionisation (EoR). It has driven the construction of the new generation of lowfrequency radio interferometric arrays, including the Hydrogen Epoch of Reionization Array (HERA). The main difficulty in measuring the 21 cm signal is the presence of bright foregrounds that require very accurate interferometric calibration. However, the non-smooth instrumental response of the antenna as a result of mutual coupling complicates the calibration process by introducing non-smooth calibration errors. Additionally, incomplete sky models are typically used in calibration due to the limited depth and resolution of current source catalogues. Combined with the instrumental response, the use of incomplete sky models during calibration can result in non-smooth calibration errors. These, overall, impart spectral structure on smooth foregrounds, leading to foreground power leakage into the EoR window. In this thesis we explored the use of fringe rate filters (Parsons et al., 2016) as a mean to mitigate calibration errors resulting from the effects of mutual coupling and the use of an incomplete sky model during calibration. We found that the use of a simple notch filter mitigates calibration errors reducing the foreground power leakage into the EoR window by a factor of ∼ 102. Thyagarajan et al. (2018) proposed the use of closure phase quantities as a means to detect the 21 cm signal, which has the advantage of being independent (to first order) from calibration errors and, therefore, bypasses the need for accurate calibration. In this thesis, we explore the impact of primary beam patterns affected by mutual coupling on the closure phase. We found that primary beams affected by mutual coupling lead to a leakage of foreground power into the EoR window, which can be up to ∼ 104 times and is mainly caused by the unsmooth spectral structure primary of primary beam sidelobes affected by mutual coupling. This power leakage was confined to k < 0.3 pseudo h Mpc−1. Lastly, we also proposed and demonstrated an analysis technique that can be used to derive a flux scale correction in post-calibrated HERA data. We found that after applying flux scale correction to calibrated HERA data, the bandpass error reduces significantly, with an improvement of 6%. The derived flux scale correction was antenna-independent, and it can be applied to fix the overall visibility spectrum scale of H4C data post-calibration in a fashion similar to Jacobs et al. (2013). , Thesis (PhD) -- Faculty of Science, Physics and Electronics, 2024
- Full Text:
- Date Issued: 2024
A comprehensive review of the taxonomic diversity within the freshwater catfish genus Parauchenoglanis (Siluriformes, Auchenoglanididae)
- Authors: Sithole, Yonela
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/402992 , vital:69912
- Description: Thesis embargoed. To be released early 2026. , Thesis (PhD) -- Faculty of Science, Ichthyology & Fisheries Science, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Sithole, Yonela
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/402992 , vital:69912
- Description: Thesis embargoed. To be released early 2026. , Thesis (PhD) -- Faculty of Science, Ichthyology & Fisheries Science, 2023
- Full Text:
- Date Issued: 2023-10-13
A council of women
- Authors: Sobekwa, Lelethu Anathi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435988 , vital:73218
- Description: This thesis comprises extracts of life writing written in short prose forms. The work reads like a novella and I have been inspired by Margaret Patton Chapman’s approach to the novella, where she condenses “the telling of a long story time wise”, so that a story occurring over two years can be told over two pages. The thesis explores relationships between mother, daughter, grandmother and granddaughter, each with different life experiences and each teaching the next generation about how to navigate life as politically, socially and economically disadvantaged women. I have also drawn inspiration from authors such as NoViolet Bulawayo who explores the hypocrisies of the church and the government in We Need New Names. In Kate Bernheimer’s “Fairy Tale is Form, Form is Fairy Tale” she writes about fairy tales adopting “intuitive logic” or telling in the form of “this happens and then this happens” while the explanation behind the events is not spelt out but rather exists between the lines. My thesis adopts this style of writing by allowing the reader to understand what is being said without over-simplifying. To this end, I have used the concept of place modelled on Es’kia Mphahlele’s In Corner B, where characters are inscribed in relation to the spaces they inhabit. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Sobekwa, Lelethu Anathi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435988 , vital:73218
- Description: This thesis comprises extracts of life writing written in short prose forms. The work reads like a novella and I have been inspired by Margaret Patton Chapman’s approach to the novella, where she condenses “the telling of a long story time wise”, so that a story occurring over two years can be told over two pages. The thesis explores relationships between mother, daughter, grandmother and granddaughter, each with different life experiences and each teaching the next generation about how to navigate life as politically, socially and economically disadvantaged women. I have also drawn inspiration from authors such as NoViolet Bulawayo who explores the hypocrisies of the church and the government in We Need New Names. In Kate Bernheimer’s “Fairy Tale is Form, Form is Fairy Tale” she writes about fairy tales adopting “intuitive logic” or telling in the form of “this happens and then this happens” while the explanation behind the events is not spelt out but rather exists between the lines. My thesis adopts this style of writing by allowing the reader to understand what is being said without over-simplifying. To this end, I have used the concept of place modelled on Es’kia Mphahlele’s In Corner B, where characters are inscribed in relation to the spaces they inhabit. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2023
- Full Text:
- Date Issued: 2023-10-13
A molecular investigation of stem-galling Tetramesa Walker (Hymenoptera: Eurytomidae) on African grasses: applications to biological control
- Van Steenderen, Clarke Julian Mignon
- Authors: Van Steenderen, Clarke Julian Mignon
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432565 , vital:72881 , DOI 10.21504/10962/432565
- Description: South Africa is a larger donor than receiver of alien grasses, where approximately 15% (_ 165 spp.) of the country's native grass species have become naturalised elsewhere. Many of these grasses have become serious invaders, causing significant damage to native species, habitat structure, and ecosystem functioning. Biological control is a sustainable and cost-effective method for the control of invasive weeds, but its application to invasive grasses has been approached with trepidation in the past due to the fears of a lack of host-specific herbivores that may cause non-target damage to agriculturally-important crops. The Tetramesa Walker genus (Hymenoptera: Eurytomidae) is one of three genera in the family that feed exclusively on grasses, and have a record of being host-specific to a particular species, or complex of closely-related congeners. There are over 200 described Tetramesa species, but this taxonomic effort has occurred almost exclusively in the Northern Hemisphere. Only about 2% of the described species are from Africa, with none from southern Africa despite the high diversity of grasses in the region. The low morphological variability between many Tetramesa groups has made identification difficult, where there may in fact be multiple undiscovered cryptic species. This thesis generated genetic sequence data (mitochondrial COI and nuclear 28S) that revealed at least eight native southern African Tetramesa taxa that are new to science, focusing particularly on the assemblages associated with Eragrostis curvula Nees (African lovegrass) and Sporobolus pyramidalis Beauv. and S. natalensis Steud. (giant rat's tail grass) which are alien invasive pests in Australia. Approximately 200 eurytomid wasps were collected and sequenced from 19 grass species across six South African provinces. Additionally, 27 grass species were sequenced using four gene regions (rps16-trnK, rps16, rpl32-trnL, and ITS), which were added to existing sequence data to build a dataset comprising over 700 sequences. Field host ranges and the use of host grass genetic proxies were important in making inferences about the host-specificity of eurytomid wasps of interest. Nine Tetramesa groups appeared to be host-specific to a single grass species, while six Tetramesa were associated with multiple species in a single grass genus. Since S. pyramidalis, S. natalensis, S. africanus, Hyparrhenia hirta, E. trichophora, and Andropogon gayanus are weeds elsewhere, there are at least six potential Tetramesa biological control agents that have been identified. A high diversity of Tetramesa on grasses within the Eragrostis genus was reported, with at least four taxa associated with E. curvula. It is currently uncertain whether these taxa represent different cryptic species or intraspecific populations that are the result of geographic sub-structuring. No-choice host-specificity testing using Tetramesa sp. 4 on E. curvula revealed that the wasp could complete its lifecycle on two non-target African grasses; namely E. plana and E. planiculmis. The wasp was also recorded on other Eragrostis species in the field (namely E. biflora and E. capensis). Using grass genetic sequences obtained in this study, it was found that there are four native Australian Eragrostis species that are more closely related to target E. curvula than to the non-target E. plana and E. planiculmis. This suggests that Tetramesa sp. 4 may not be suitably host-specific for use as a biological control agent. Further host-specificity testing on these native Australian species is required, however, before this insect is ruled out completely. The Tetramesa on S. pyramidalis (Tetramesa sp. 1), and the unidentified Sporobolus species presumed to be S. africanus, were suitably host-specific to be used as biological control agents. Since it was unclear whether some phylogenetic clades were true species or intraspecific populations, which is essential to understand when selecting agents for biological control, a new piece of software, SPEDE-sampler", was developed. It offers users of the Generalised Mixed Yule Coalescent (GMYC) species delimitation model a means of assessing the degree to which sampling effects such as data size and parameter choice can influence species diversity estimates. When applied to the Tetramesa data set, the software assisted in identifying which groups may contain cryptic species, uncovering that the COI marker is affected more by singletons than the 28S marker (i.e. species diversity tends to be overestimated), and confirming putative Tetramesa taxa that could be useful for biological control programmes going forward. This thesis has provided evidence that South Africa contains a diverse assemblage of Tetramesa and other eurytomids that are closely associated with their grass hosts, and that many of these taxa hold promise for grass biological control. This work has also highlighted the importance of integrative taxonomy in the discovery of novel taxa, and that biological control practitioners need to be aware of the caveats of each line of evidence used in the delimitation of putative species. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Van Steenderen, Clarke Julian Mignon
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432565 , vital:72881 , DOI 10.21504/10962/432565
- Description: South Africa is a larger donor than receiver of alien grasses, where approximately 15% (_ 165 spp.) of the country's native grass species have become naturalised elsewhere. Many of these grasses have become serious invaders, causing significant damage to native species, habitat structure, and ecosystem functioning. Biological control is a sustainable and cost-effective method for the control of invasive weeds, but its application to invasive grasses has been approached with trepidation in the past due to the fears of a lack of host-specific herbivores that may cause non-target damage to agriculturally-important crops. The Tetramesa Walker genus (Hymenoptera: Eurytomidae) is one of three genera in the family that feed exclusively on grasses, and have a record of being host-specific to a particular species, or complex of closely-related congeners. There are over 200 described Tetramesa species, but this taxonomic effort has occurred almost exclusively in the Northern Hemisphere. Only about 2% of the described species are from Africa, with none from southern Africa despite the high diversity of grasses in the region. The low morphological variability between many Tetramesa groups has made identification difficult, where there may in fact be multiple undiscovered cryptic species. This thesis generated genetic sequence data (mitochondrial COI and nuclear 28S) that revealed at least eight native southern African Tetramesa taxa that are new to science, focusing particularly on the assemblages associated with Eragrostis curvula Nees (African lovegrass) and Sporobolus pyramidalis Beauv. and S. natalensis Steud. (giant rat's tail grass) which are alien invasive pests in Australia. Approximately 200 eurytomid wasps were collected and sequenced from 19 grass species across six South African provinces. Additionally, 27 grass species were sequenced using four gene regions (rps16-trnK, rps16, rpl32-trnL, and ITS), which were added to existing sequence data to build a dataset comprising over 700 sequences. Field host ranges and the use of host grass genetic proxies were important in making inferences about the host-specificity of eurytomid wasps of interest. Nine Tetramesa groups appeared to be host-specific to a single grass species, while six Tetramesa were associated with multiple species in a single grass genus. Since S. pyramidalis, S. natalensis, S. africanus, Hyparrhenia hirta, E. trichophora, and Andropogon gayanus are weeds elsewhere, there are at least six potential Tetramesa biological control agents that have been identified. A high diversity of Tetramesa on grasses within the Eragrostis genus was reported, with at least four taxa associated with E. curvula. It is currently uncertain whether these taxa represent different cryptic species or intraspecific populations that are the result of geographic sub-structuring. No-choice host-specificity testing using Tetramesa sp. 4 on E. curvula revealed that the wasp could complete its lifecycle on two non-target African grasses; namely E. plana and E. planiculmis. The wasp was also recorded on other Eragrostis species in the field (namely E. biflora and E. capensis). Using grass genetic sequences obtained in this study, it was found that there are four native Australian Eragrostis species that are more closely related to target E. curvula than to the non-target E. plana and E. planiculmis. This suggests that Tetramesa sp. 4 may not be suitably host-specific for use as a biological control agent. Further host-specificity testing on these native Australian species is required, however, before this insect is ruled out completely. The Tetramesa on S. pyramidalis (Tetramesa sp. 1), and the unidentified Sporobolus species presumed to be S. africanus, were suitably host-specific to be used as biological control agents. Since it was unclear whether some phylogenetic clades were true species or intraspecific populations, which is essential to understand when selecting agents for biological control, a new piece of software, SPEDE-sampler", was developed. It offers users of the Generalised Mixed Yule Coalescent (GMYC) species delimitation model a means of assessing the degree to which sampling effects such as data size and parameter choice can influence species diversity estimates. When applied to the Tetramesa data set, the software assisted in identifying which groups may contain cryptic species, uncovering that the COI marker is affected more by singletons than the 28S marker (i.e. species diversity tends to be overestimated), and confirming putative Tetramesa taxa that could be useful for biological control programmes going forward. This thesis has provided evidence that South Africa contains a diverse assemblage of Tetramesa and other eurytomids that are closely associated with their grass hosts, and that many of these taxa hold promise for grass biological control. This work has also highlighted the importance of integrative taxonomy in the discovery of novel taxa, and that biological control practitioners need to be aware of the caveats of each line of evidence used in the delimitation of putative species. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
A study on visual inspection of citrus sorters in a packhouse in the Eastern Cape of South Africa
- Authors: Maher, Christopher Richard
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424256 , vital:72137
- Description: Background and Purpose. The South African citrus industry is a major global producer of citrus as well as the second largest exporter of citrus fruit in the world. This industry provides employment to an estimated 112 000 workers in South Africa and is vital in providing economic opportunities to communities such as those in the Sunday’s River Valley in the Eastern Cape province of South Africa due to the low employment and education levels within this province. Citrus sorting is a visual inspection task that requires workers to sustain attention and remain vigilant for the duration of a working shift. Their role in the packhouse is to ensure that no defective products are packed for export or the local market and that the fruit meets the customers’ expectations. Since the demands of sorting citrus are poorly understood, this study attempted to assess the effect that sorting citrus has on vigilance performance as well as attempt to quantify perceived workload while taking into account different contextual factors that affect perceptions of this working task. Methods. This study was conducted within a citrus packhouse in the Eastern Cape province of South Africa. The sample was comprised of individuals employed by the packhouse as citrus sorters. In addition to a recruitment and information session, testing was conducted at three intervals during a working shift on four consecutive days. Each time, indicators of vigilance, such as correct responses, sensitivity, reaction time, false alarms and misses, were collected during a 5-minute computerised version of the Mackworth Clock-test, while perceived workload was assessed with the NASA-TLX scale, and sleepiness was recording using the WITS Sleepiness Scale. Furthermore, an open-ended question was asked to further understand factors affecting the ability of participants to concentrate during their task of sorting. Results. 18 participants consented to participate in this study. 16 of these individuals identified as female with an average age of 30 years (± 7). 83% of participants were of Black African descent and were isiXhosa speakers, while 17% of participants were of Coloured descent and Afrikaans speakers. This study found that performance, as measured by the percentage of correct responses, sensitivity and reaction time on the 5-minute long Mackworth Clock Test was not significantly affected as time-on-task for sorting citrus increased during a working shift, neither did performance on the vigilance test change as days of the week proceeded. However, ‘misses’ during the vigilance test were found to significantly decrease over the course of a working shift, thus contradicting the expected outcomes of this study. Perceived workload of sorting citrus, as well as perceived sleepiness, significantly increased with time-on-task during the course of a working shift. The major contributions for this increase in perceived workload while sorting citrus were derived from the Mental Demand and Physical Demand sub-scale for the NASA-TLX. However, responses from the open-ended question indicated that participants generally enjoyed their work, although there were factors, such as the nature of fruit and social set-up of work, that negatively affected this perception. Discussion. The results from this study contradicted the researcher’s expectations. It was anticipated that measures of correct responses and sensitivity would decrease and misses, and reaction time would increase with time-on-task for sorting citrus, yet vigilance indicators from the Mackworth Clock Test generally indicated no change in vigilance, and, according to “misses” even improved with time-on-task. A likely explanation for this is that the use of a 5-minute Mackworth Clock-test was unsuitable in this context, or rather, the time of this test was not long enough to induce a ‘vigilance decrement’. Furthermore, in order to administer this vigilance test, participants were taken off the production line and led to a testing room which most likely increased their levels of arousal, thus affecting performance on the vigilance test. However, even though perceived sleepiness was found to significantly increase over the course of a working shift, these data correlated poorly with the vigilance results, thus contradicting the expected outcomes of the study. Mental demand significantly increased, possibly due to the demand of attentional informational processing required for sorting, as well as various environmental factors present within the packhouse. Physical demand, too, significantly increased as workers were required to remain standing throughout their working task as well as to make use of their upper extremities to remove defective fruit. Correlation analyses showed significantly weak correlation for Mackworth Clock Test variables and sleepiness ratings to all other variables. NASA-TLX variables, however, generally showed significantly moderate correlations with one another. Conclusion. It remains unclear how vigilance changes and sustained attention while sorting citrus, since the experiment did not show changes in performance. This is largely attributed to the methodological set-up which could have increased arousal and therefore affected vigilance. It is recommended that future studies research vigilance and sustained attention during the sorting itself, rather than attempting to infer vigilance results from a computerised vigilance test. Perceived workload of sorting, however, increased over the course of a working shift due to significant increases in perceptions of the physical and mental demands of sorting. Future studies should address concerns relating to the physical demand of sorting. Furthermore, it would be beneficial to compare responses of day and night shift sorters to further understand how the relationship between these variables may change. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Maher, Christopher Richard
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424256 , vital:72137
- Description: Background and Purpose. The South African citrus industry is a major global producer of citrus as well as the second largest exporter of citrus fruit in the world. This industry provides employment to an estimated 112 000 workers in South Africa and is vital in providing economic opportunities to communities such as those in the Sunday’s River Valley in the Eastern Cape province of South Africa due to the low employment and education levels within this province. Citrus sorting is a visual inspection task that requires workers to sustain attention and remain vigilant for the duration of a working shift. Their role in the packhouse is to ensure that no defective products are packed for export or the local market and that the fruit meets the customers’ expectations. Since the demands of sorting citrus are poorly understood, this study attempted to assess the effect that sorting citrus has on vigilance performance as well as attempt to quantify perceived workload while taking into account different contextual factors that affect perceptions of this working task. Methods. This study was conducted within a citrus packhouse in the Eastern Cape province of South Africa. The sample was comprised of individuals employed by the packhouse as citrus sorters. In addition to a recruitment and information session, testing was conducted at three intervals during a working shift on four consecutive days. Each time, indicators of vigilance, such as correct responses, sensitivity, reaction time, false alarms and misses, were collected during a 5-minute computerised version of the Mackworth Clock-test, while perceived workload was assessed with the NASA-TLX scale, and sleepiness was recording using the WITS Sleepiness Scale. Furthermore, an open-ended question was asked to further understand factors affecting the ability of participants to concentrate during their task of sorting. Results. 18 participants consented to participate in this study. 16 of these individuals identified as female with an average age of 30 years (± 7). 83% of participants were of Black African descent and were isiXhosa speakers, while 17% of participants were of Coloured descent and Afrikaans speakers. This study found that performance, as measured by the percentage of correct responses, sensitivity and reaction time on the 5-minute long Mackworth Clock Test was not significantly affected as time-on-task for sorting citrus increased during a working shift, neither did performance on the vigilance test change as days of the week proceeded. However, ‘misses’ during the vigilance test were found to significantly decrease over the course of a working shift, thus contradicting the expected outcomes of this study. Perceived workload of sorting citrus, as well as perceived sleepiness, significantly increased with time-on-task during the course of a working shift. The major contributions for this increase in perceived workload while sorting citrus were derived from the Mental Demand and Physical Demand sub-scale for the NASA-TLX. However, responses from the open-ended question indicated that participants generally enjoyed their work, although there were factors, such as the nature of fruit and social set-up of work, that negatively affected this perception. Discussion. The results from this study contradicted the researcher’s expectations. It was anticipated that measures of correct responses and sensitivity would decrease and misses, and reaction time would increase with time-on-task for sorting citrus, yet vigilance indicators from the Mackworth Clock Test generally indicated no change in vigilance, and, according to “misses” even improved with time-on-task. A likely explanation for this is that the use of a 5-minute Mackworth Clock-test was unsuitable in this context, or rather, the time of this test was not long enough to induce a ‘vigilance decrement’. Furthermore, in order to administer this vigilance test, participants were taken off the production line and led to a testing room which most likely increased their levels of arousal, thus affecting performance on the vigilance test. However, even though perceived sleepiness was found to significantly increase over the course of a working shift, these data correlated poorly with the vigilance results, thus contradicting the expected outcomes of the study. Mental demand significantly increased, possibly due to the demand of attentional informational processing required for sorting, as well as various environmental factors present within the packhouse. Physical demand, too, significantly increased as workers were required to remain standing throughout their working task as well as to make use of their upper extremities to remove defective fruit. Correlation analyses showed significantly weak correlation for Mackworth Clock Test variables and sleepiness ratings to all other variables. NASA-TLX variables, however, generally showed significantly moderate correlations with one another. Conclusion. It remains unclear how vigilance changes and sustained attention while sorting citrus, since the experiment did not show changes in performance. This is largely attributed to the methodological set-up which could have increased arousal and therefore affected vigilance. It is recommended that future studies research vigilance and sustained attention during the sorting itself, rather than attempting to infer vigilance results from a computerised vigilance test. Perceived workload of sorting, however, increased over the course of a working shift due to significant increases in perceptions of the physical and mental demands of sorting. Future studies should address concerns relating to the physical demand of sorting. Furthermore, it would be beneficial to compare responses of day and night shift sorters to further understand how the relationship between these variables may change. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2023
- Full Text:
- Date Issued: 2023-10-13
African linguistic phenomenology as illustrated through the Setswana language
- Authors: Modisakeng, Lemogang
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425089 , vital:72208
- Description: Embargoed. Expected release date 2025. , Thesis (MA) -- Faculty of Humanities, Philosophy, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Modisakeng, Lemogang
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425089 , vital:72208
- Description: Embargoed. Expected release date 2025. , Thesis (MA) -- Faculty of Humanities, Philosophy, 2023
- Full Text:
- Date Issued: 2023-10-13
African population prevalent genetic variations of dihydropyrimidine dehydrogenase as the 5-flourouracil cancer drug metabolizing enzyme: computational approaches towards pharmacogenomics studies
- Authors: Tendwa, Maureen Bilinga
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432263 , vital:72856 , DOI 10.21504/10962/432270
- Description: In an era of newly emerging cases of non-communicable diseases such as cancer, research is vital for both the medical and economic well-being of humanity. Pharmacogenomics has laidthegroundworkfor the identification of potential genes in cancer progression and treatment outcome investigations. Researchers are increasingly discovering heterogeneity in the efficacy and toxicity responses of drugmetabolizing enzymes (DMEs) in diverse patient populations receiving anti-cancer therapy. DMEs comprise of Phase I (Cytochrome P450s) and Phase II (glutathione-S-transferases (GSTs), UDP-glucuronosyltransferases (UGTs), and dihydropyrimidine dehydrogenases (DPD)enzymes. The main cause of disparity in DME treatment outcomes is genetic variation,which causes missense mutations leading to structural and kinetic properties of the enzyme. These modifications have a deleterious impact on the pharmacodynamics and pharmacokinetics of drugs through multiple mechanisms. Presently, most cancer medicines are manufacturedin developed countries based on the genetic background of non-African subpopulations. Thus, these drugs may not be optimally effective or can cause adverse side effects. Even though heterogeneity in toxicity and efficacy of these drugs has been observed in African descent, the basis of this population variance remains partially understood. For instance,a deficiencyof DPD, the first-rate limiting metabolizing enzyme in the pyrimidinepathway, causes severe toxicity when exposed to 5-fluorouracil (5-FU) chemotherapy. However, minimum studies have been conducted to unravel itsmolecular mechanismwhich may unravel the observed drug treatment outcomes.The aim of this pharmacogenomics study was to determine the underlying mechanism by which DPD missense mutations, which are associated with an African ancestry subpopulation, provoke dysfunctional 5-FU metabolism, resulting in drug toxicity. This knowledge will be critical in designing drug modulators to aid in the restoration of DPD function, a hallmark of precision medicine. Therefore, in the first part of the research we identified and reviewed the general role of Phase I and Phase II cancer drug metabolizing enzymes. We then used World Health Organization (WHO) essential medicine and drug.com to authenticate the usage of 5-FU as an anti-cancer treatment agent. The 3D structure and chemical structure of the agent was then downloaded from the Drug bank. Subsequently, Human Mutation Analysis - Variant Analysis PORtal (HUMA) and Mendelian Inheritance in Man (OMIM) were used to obtain data on DPD non-synonymous genetic variants. Additionally, the aggregate information of DPD missense mutations and their relation to human health were extracted from ClinVar and Pharmacogenomics Knowledge Base (PharmKGB). This information, along with additional data from single nucleotide polymorphisms (dbSNP), 1000 Genomes Project and Exome Sequencing Project (ESP MAF) considering variants classified based on their minor allele frequency (MAF) of 0.001, as well as research articles, consolidated information on missense mutations associated with African subpopulations. Finally, the wild type (WT) and detected mutation sequences were obtained from the Universal Protein Resources database (UniProt). However, because the 3D structure of human DPD was missing, the dimeric wild type (WT) human 3-dimensional (3D) structure was modeled via MODELLER using the pig’s structure as a template. PRIMO, HHpred, and the Protein Data Bank (PDB) were all used to locate the suitable template. As a result, six clinical (C29R, M166V, Y186C, S534N, I543V, and D949V) and thirteen non-clinical (S201R, K259E, D342N, D432N, S492L, R592Q, A664S, G674D, A721T, V732G, T768K, R886C, and L993R) mutations were discovered. Using AMBER tools, we then determined accurate force field parameters for each monomer of DPD protein's Fe2+ centers. Following the creation of each mutation model structure in Discovery Studio, the resulting AMBER force field parameters were inferred. For each model structure, a drug free (inactive/open-conformation) and drug bound (active/closed-conformation) model structure was created (WT and mutations). The model structures were validated using the consensus of three validation programs, namely ERRAT, PROCHECK, and ProSA. Similarly, the impact on structural functionalities was predicted by consensus from Variant Analysis Porta (VAPOR) web server, which include three support vector machines (SVM)-based tools; PhD-SNP, MUpro, and I-Mutation. After protonation in the H++ web server, the six clinical and thirteen non-clinical (six active site and seven non-active site) mutations identified were then exposed to 600 ns molecular dynamic (MD) simulation. The non-clinical data was divided into two categories to better understand the impact of the mutation based on its position in the protein: six catalytic-domain (R592Q, A664S, G674D, A721T, V732G, and T768K) and seven remote (S201R, K259E, D342N, D432N, S492L, R886C, and L993R) missense mutations. The post-MD analysis was done using the typical existing computational global investigations [RMSD, all versus all RMSD, RMSF, RG, hydrogen bonds (H-bonds) and dynamic cross correlation (DCC)]. In addition, we used in silico tools newly developed within the Research Unit in Bioinformatics (RUBI) group, such as comparative essential dynamics (ED)-principal component analysis and dynamic residue network (DRN) multi-metric [betweenness centrality (BC), closeness centrality (CC), degree of centrality (DC), eigen-centrality (EC) and Katz centrality (KC)] analysis algorithms. From the analysis, it was observed that the loop regions of the mutation proteins had increased loop flexibility, particularly around the catalytic loop, which could account for the enhanced asymmetric behavior of the mutation’s monomers compared to the WT. Notably, the A664S mutant showed relatively lower fluctuations, deviating from the observed heightened flexibility in other mutants. A general decrease in hydrogen bonds was observed in the 5-FU binding environment of the mutations compared to the WT. In particular, 5-FU contact analysis of the WT versus the mutation revealed a reduction in contact between core 5-FU binding residues and catalytic residues Cys671 and Ser670, which form hydrogen bonds that initiate DPD catalytic action. Additionally, BC was used to quantify the importance of a protein residue based on how often it acted as a bridge along the shortest paths between other residues. It reflected the potential control or influence a residue may have over communication between different parts of a protein structure. DC assesses the number of connections or interactions a residue had with other residues in the protein, indicating its overall connectivity within the structure. In both drug free and drug bound state, DPD data from the active site hubs' BC and DC revealed a dimeric asymmetric communication pathway per monomer involving a cluster of newly introduced hubs ensemble along the oxidoreduction conduit from NADPH to 5-FU. The two BC communication pathways were located more on the interior of the oxidoreduction conduit, while the two DC communication pathways were located on the exterior. In both cases, one pathway dominated the other. Partially lost function reported in mutation systems could be credited to the compensation communication response to the catalytic site via the least compromised routes. Similar patterns were observed in allosteric communication pathways to the active site induced by remote mutations. Mutations may have destabilized the active-loop and 5-FU binding environment, resulting in a compensatory mechanism seen by the addition of new hubs to the communication network. Surprisingly, EC hubs in the WT were found within the catalytic site domain, indicating that the region is important in 5-FU metabolism. EC measured the importance of a residue by considering both its own degree of connectivity and the degrees of connectivity with its neighboring residues, highlighting its significance in information flow and communication. Herein, EC hubs in mutant systems were found to lose this importance, with active site domain mutations suffering the most. This could explain why non-clinical catalytic domain mutations R592Q, A664S, and G674D, as well as clinical catalytic domain mutations S534N and I543V, experienced drug exit in one of their monomers during simulation. In contrast, there was no 5-FU exit in the non-clinical remote domain. Additionally, aside from the active site, KC hubs were also found around the cofactors, indicating that these components were equally important in DPD overall function. KC combines the concepts of both degree centrality and eigen-centrality, it incorporated both direct and indirect interactions to evaluate the importance of a residue, assigning higher centrality to residues that have connections to other highly central residues. Hence, providing a more comprehensive measure of influence within the protein network. More importantly, CC is known to measure how efficiently a residue can interact with other residues in the protein, considering the shortest path lengths. It indicates the proximity of a residue to others, suggesting its potential for information transfer or functional integration. CC revealed that the majority of persistent hubs were found within the protein-cores known as cold-spots. Overall, this study highlighted the communication pathways triggered by active site domain mutations, as well as the allosteric communication pathways triggered by each remote mutation in both drug free and drug bound states of the DPD enzyme. Both clinical and non-clinical mutations revealed each protein's adaptive compensation mechanism, which results in partial function loss. In each case, the communication network of the different monomers changed from inactive to activated DPD protein. Cold-spot areas were discovered to contain key persistent residues involved in protein function and stability. These areas have been proposed as potential targets for new or repurposed pharmacological modulators that can restore enzyme function. In the pursuit of precision medicine, it also lays the groundwork for detecting and explaining the molecular mechanisms of other drug metabolizing enzymes related to the African-descent subpopulation. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Tendwa, Maureen Bilinga
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432263 , vital:72856 , DOI 10.21504/10962/432270
- Description: In an era of newly emerging cases of non-communicable diseases such as cancer, research is vital for both the medical and economic well-being of humanity. Pharmacogenomics has laidthegroundworkfor the identification of potential genes in cancer progression and treatment outcome investigations. Researchers are increasingly discovering heterogeneity in the efficacy and toxicity responses of drugmetabolizing enzymes (DMEs) in diverse patient populations receiving anti-cancer therapy. DMEs comprise of Phase I (Cytochrome P450s) and Phase II (glutathione-S-transferases (GSTs), UDP-glucuronosyltransferases (UGTs), and dihydropyrimidine dehydrogenases (DPD)enzymes. The main cause of disparity in DME treatment outcomes is genetic variation,which causes missense mutations leading to structural and kinetic properties of the enzyme. These modifications have a deleterious impact on the pharmacodynamics and pharmacokinetics of drugs through multiple mechanisms. Presently, most cancer medicines are manufacturedin developed countries based on the genetic background of non-African subpopulations. Thus, these drugs may not be optimally effective or can cause adverse side effects. Even though heterogeneity in toxicity and efficacy of these drugs has been observed in African descent, the basis of this population variance remains partially understood. For instance,a deficiencyof DPD, the first-rate limiting metabolizing enzyme in the pyrimidinepathway, causes severe toxicity when exposed to 5-fluorouracil (5-FU) chemotherapy. However, minimum studies have been conducted to unravel itsmolecular mechanismwhich may unravel the observed drug treatment outcomes.The aim of this pharmacogenomics study was to determine the underlying mechanism by which DPD missense mutations, which are associated with an African ancestry subpopulation, provoke dysfunctional 5-FU metabolism, resulting in drug toxicity. This knowledge will be critical in designing drug modulators to aid in the restoration of DPD function, a hallmark of precision medicine. Therefore, in the first part of the research we identified and reviewed the general role of Phase I and Phase II cancer drug metabolizing enzymes. We then used World Health Organization (WHO) essential medicine and drug.com to authenticate the usage of 5-FU as an anti-cancer treatment agent. The 3D structure and chemical structure of the agent was then downloaded from the Drug bank. Subsequently, Human Mutation Analysis - Variant Analysis PORtal (HUMA) and Mendelian Inheritance in Man (OMIM) were used to obtain data on DPD non-synonymous genetic variants. Additionally, the aggregate information of DPD missense mutations and their relation to human health were extracted from ClinVar and Pharmacogenomics Knowledge Base (PharmKGB). This information, along with additional data from single nucleotide polymorphisms (dbSNP), 1000 Genomes Project and Exome Sequencing Project (ESP MAF) considering variants classified based on their minor allele frequency (MAF) of 0.001, as well as research articles, consolidated information on missense mutations associated with African subpopulations. Finally, the wild type (WT) and detected mutation sequences were obtained from the Universal Protein Resources database (UniProt). However, because the 3D structure of human DPD was missing, the dimeric wild type (WT) human 3-dimensional (3D) structure was modeled via MODELLER using the pig’s structure as a template. PRIMO, HHpred, and the Protein Data Bank (PDB) were all used to locate the suitable template. As a result, six clinical (C29R, M166V, Y186C, S534N, I543V, and D949V) and thirteen non-clinical (S201R, K259E, D342N, D432N, S492L, R592Q, A664S, G674D, A721T, V732G, T768K, R886C, and L993R) mutations were discovered. Using AMBER tools, we then determined accurate force field parameters for each monomer of DPD protein's Fe2+ centers. Following the creation of each mutation model structure in Discovery Studio, the resulting AMBER force field parameters were inferred. For each model structure, a drug free (inactive/open-conformation) and drug bound (active/closed-conformation) model structure was created (WT and mutations). The model structures were validated using the consensus of three validation programs, namely ERRAT, PROCHECK, and ProSA. Similarly, the impact on structural functionalities was predicted by consensus from Variant Analysis Porta (VAPOR) web server, which include three support vector machines (SVM)-based tools; PhD-SNP, MUpro, and I-Mutation. After protonation in the H++ web server, the six clinical and thirteen non-clinical (six active site and seven non-active site) mutations identified were then exposed to 600 ns molecular dynamic (MD) simulation. The non-clinical data was divided into two categories to better understand the impact of the mutation based on its position in the protein: six catalytic-domain (R592Q, A664S, G674D, A721T, V732G, and T768K) and seven remote (S201R, K259E, D342N, D432N, S492L, R886C, and L993R) missense mutations. The post-MD analysis was done using the typical existing computational global investigations [RMSD, all versus all RMSD, RMSF, RG, hydrogen bonds (H-bonds) and dynamic cross correlation (DCC)]. In addition, we used in silico tools newly developed within the Research Unit in Bioinformatics (RUBI) group, such as comparative essential dynamics (ED)-principal component analysis and dynamic residue network (DRN) multi-metric [betweenness centrality (BC), closeness centrality (CC), degree of centrality (DC), eigen-centrality (EC) and Katz centrality (KC)] analysis algorithms. From the analysis, it was observed that the loop regions of the mutation proteins had increased loop flexibility, particularly around the catalytic loop, which could account for the enhanced asymmetric behavior of the mutation’s monomers compared to the WT. Notably, the A664S mutant showed relatively lower fluctuations, deviating from the observed heightened flexibility in other mutants. A general decrease in hydrogen bonds was observed in the 5-FU binding environment of the mutations compared to the WT. In particular, 5-FU contact analysis of the WT versus the mutation revealed a reduction in contact between core 5-FU binding residues and catalytic residues Cys671 and Ser670, which form hydrogen bonds that initiate DPD catalytic action. Additionally, BC was used to quantify the importance of a protein residue based on how often it acted as a bridge along the shortest paths between other residues. It reflected the potential control or influence a residue may have over communication between different parts of a protein structure. DC assesses the number of connections or interactions a residue had with other residues in the protein, indicating its overall connectivity within the structure. In both drug free and drug bound state, DPD data from the active site hubs' BC and DC revealed a dimeric asymmetric communication pathway per monomer involving a cluster of newly introduced hubs ensemble along the oxidoreduction conduit from NADPH to 5-FU. The two BC communication pathways were located more on the interior of the oxidoreduction conduit, while the two DC communication pathways were located on the exterior. In both cases, one pathway dominated the other. Partially lost function reported in mutation systems could be credited to the compensation communication response to the catalytic site via the least compromised routes. Similar patterns were observed in allosteric communication pathways to the active site induced by remote mutations. Mutations may have destabilized the active-loop and 5-FU binding environment, resulting in a compensatory mechanism seen by the addition of new hubs to the communication network. Surprisingly, EC hubs in the WT were found within the catalytic site domain, indicating that the region is important in 5-FU metabolism. EC measured the importance of a residue by considering both its own degree of connectivity and the degrees of connectivity with its neighboring residues, highlighting its significance in information flow and communication. Herein, EC hubs in mutant systems were found to lose this importance, with active site domain mutations suffering the most. This could explain why non-clinical catalytic domain mutations R592Q, A664S, and G674D, as well as clinical catalytic domain mutations S534N and I543V, experienced drug exit in one of their monomers during simulation. In contrast, there was no 5-FU exit in the non-clinical remote domain. Additionally, aside from the active site, KC hubs were also found around the cofactors, indicating that these components were equally important in DPD overall function. KC combines the concepts of both degree centrality and eigen-centrality, it incorporated both direct and indirect interactions to evaluate the importance of a residue, assigning higher centrality to residues that have connections to other highly central residues. Hence, providing a more comprehensive measure of influence within the protein network. More importantly, CC is known to measure how efficiently a residue can interact with other residues in the protein, considering the shortest path lengths. It indicates the proximity of a residue to others, suggesting its potential for information transfer or functional integration. CC revealed that the majority of persistent hubs were found within the protein-cores known as cold-spots. Overall, this study highlighted the communication pathways triggered by active site domain mutations, as well as the allosteric communication pathways triggered by each remote mutation in both drug free and drug bound states of the DPD enzyme. Both clinical and non-clinical mutations revealed each protein's adaptive compensation mechanism, which results in partial function loss. In each case, the communication network of the different monomers changed from inactive to activated DPD protein. Cold-spot areas were discovered to contain key persistent residues involved in protein function and stability. These areas have been proposed as potential targets for new or repurposed pharmacological modulators that can restore enzyme function. In the pursuit of precision medicine, it also lays the groundwork for detecting and explaining the molecular mechanisms of other drug metabolizing enzymes related to the African-descent subpopulation. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
An analysis of power relations, affiliation and individuation in selected coup, secession, and inaugural speeches of Nigerian leaders, 1960-2015
- Authors: Unegbu, Osondu Chukwuemeka
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432399 , vital:72867 , DOI 10.21504/10962/432399
- Description: This study examines the positioning of Zimbabwe and the United Kingdom (UK) in the language of news articles about diplomatic relations between the two countries published in two prominent Zimbabwean newspapers, The Herald and The Standard, between 2016 and 2020, using Systemic Functional Linguistics (SFL) and Legitimation Code Theory (LCT). Zimbabwe's present diplomatic discourses are a product of its colonial and post-independence history. This thesis places The Herald and The Standard within the larger context of the Zimbabwean media landscape as a state-owned and a privately owned newspaper, respectively. It contends that the two newspapers influence the positioning of Zimbabwe and the United Kingdom in public spheres where readers engage with the news concerning diplomatic ties. The research begins with a corpus-based examination of 42 news articles published between 2016 and 2020 in The Herald and The Standard. The investigation identified several angles through which Zimbabwe and the UK are positioned in the coverage. Zimbabwe is positioned through reference to its reform agenda, intentions for free and fair elections, and its diplomatic re-engagement drive. The UK is positioned as a source of development funding and new trade agreements, while improved diplomatic relations and the removal of restrictive measures against Zimbabwe are anticipated. Fine-grained analysis was conducted on four articles, two from each newspaper, selected to reflect the trends found in the corpus analysis. The fine-grained analyses showed how linguistic resources contributed to the positioning of the UK and Zimbabwe. Complementary analyses of these articles were conducted using LCT and SFL to describe how readers' knowledge of diplomatic relations is built using language in The Herald and The Standard. The study used the concepts of constellations and cosmologies from LCT to demonstrate how diplomatic knowledge is built in these news articles. In the articles, the constellations are related to policies such as Zimbabwe's reform agenda, people (diplomats and government officials) and moral judgments. Both newspapers contain both positive and negative positioning of Zimbabwe and the UK. However, The Standard is generally critical of removing the UK's sanctions on Zimbabwe and of the Zimbabwean government's reform agenda. Meanwhile, The Herald justifies Zimbabwe's Fast-track Land Reform Programme as resulting from Britain's refusal to fund a land redistribution programme as per the 1979 Lancaster House Agreement. The use of SFL's Appraisal framework helps to examine the linguistic resources used by The Herald and The Standard to describe the positioning of the two countries in relation to each other. Lexical strings help to establish diplomatic positioning in the news articles. These couple with Appraisal to accomplish individuation and affiliation. Affect and Judgement resources revealed the decisions taken by the UK to solve the conflict by encouraging the implementation of a reform agenda by Zimbabwe. Negative evaluation is consistently used to disalign with sanctions. The emerging patterns in the data show that diplomats representing the UK affiliate with Zimbabwe's stated economic and political reforms, and the government of Zimbabwe affiliates with the new trade agreement between Zimbabwe and the UK. At the same time, the UK diplomats individuate away from human rights abuses and the Fast-track Land Reform Programme. Affiliation strengthens confidence in diplomatic ties between Zimbabwe and the UK because the emphasis is placed on restoring them despite the conditions attached. The Herald and The Standard position Zimbabwe as a reformed country ready to implement policies to improve citizens' lives and as a country violating human rights and the rule of law. They position the UK as asserting power over Zimbabwe, willing to resolve the crisis through its foreign policy, and credited for assisting Zimbabwe. This strengthens re-engagement in diplomatic relations and commercial trade between the UK and Zimbabwe. In light of these findings, Zimbabweans are encouraged to cultivate an awareness that enables them to reflect on the challenges associated with diplomatic discourses and the implications for critically analysing the re-engagement initiative. They can promote re-engagement by being cognisant of specific values portrayed in The Herald and The Standard and challenging these values in the light of policy transformation to revive the relations between the two countries. The re-engagement process requires a transformation in Zimbabwe's modus operandi to improve the country's positioning in the diplomatic relations between it and the UK. , Thesis (PhD) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Unegbu, Osondu Chukwuemeka
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432399 , vital:72867 , DOI 10.21504/10962/432399
- Description: This study examines the positioning of Zimbabwe and the United Kingdom (UK) in the language of news articles about diplomatic relations between the two countries published in two prominent Zimbabwean newspapers, The Herald and The Standard, between 2016 and 2020, using Systemic Functional Linguistics (SFL) and Legitimation Code Theory (LCT). Zimbabwe's present diplomatic discourses are a product of its colonial and post-independence history. This thesis places The Herald and The Standard within the larger context of the Zimbabwean media landscape as a state-owned and a privately owned newspaper, respectively. It contends that the two newspapers influence the positioning of Zimbabwe and the United Kingdom in public spheres where readers engage with the news concerning diplomatic ties. The research begins with a corpus-based examination of 42 news articles published between 2016 and 2020 in The Herald and The Standard. The investigation identified several angles through which Zimbabwe and the UK are positioned in the coverage. Zimbabwe is positioned through reference to its reform agenda, intentions for free and fair elections, and its diplomatic re-engagement drive. The UK is positioned as a source of development funding and new trade agreements, while improved diplomatic relations and the removal of restrictive measures against Zimbabwe are anticipated. Fine-grained analysis was conducted on four articles, two from each newspaper, selected to reflect the trends found in the corpus analysis. The fine-grained analyses showed how linguistic resources contributed to the positioning of the UK and Zimbabwe. Complementary analyses of these articles were conducted using LCT and SFL to describe how readers' knowledge of diplomatic relations is built using language in The Herald and The Standard. The study used the concepts of constellations and cosmologies from LCT to demonstrate how diplomatic knowledge is built in these news articles. In the articles, the constellations are related to policies such as Zimbabwe's reform agenda, people (diplomats and government officials) and moral judgments. Both newspapers contain both positive and negative positioning of Zimbabwe and the UK. However, The Standard is generally critical of removing the UK's sanctions on Zimbabwe and of the Zimbabwean government's reform agenda. Meanwhile, The Herald justifies Zimbabwe's Fast-track Land Reform Programme as resulting from Britain's refusal to fund a land redistribution programme as per the 1979 Lancaster House Agreement. The use of SFL's Appraisal framework helps to examine the linguistic resources used by The Herald and The Standard to describe the positioning of the two countries in relation to each other. Lexical strings help to establish diplomatic positioning in the news articles. These couple with Appraisal to accomplish individuation and affiliation. Affect and Judgement resources revealed the decisions taken by the UK to solve the conflict by encouraging the implementation of a reform agenda by Zimbabwe. Negative evaluation is consistently used to disalign with sanctions. The emerging patterns in the data show that diplomats representing the UK affiliate with Zimbabwe's stated economic and political reforms, and the government of Zimbabwe affiliates with the new trade agreement between Zimbabwe and the UK. At the same time, the UK diplomats individuate away from human rights abuses and the Fast-track Land Reform Programme. Affiliation strengthens confidence in diplomatic ties between Zimbabwe and the UK because the emphasis is placed on restoring them despite the conditions attached. The Herald and The Standard position Zimbabwe as a reformed country ready to implement policies to improve citizens' lives and as a country violating human rights and the rule of law. They position the UK as asserting power over Zimbabwe, willing to resolve the crisis through its foreign policy, and credited for assisting Zimbabwe. This strengthens re-engagement in diplomatic relations and commercial trade between the UK and Zimbabwe. In light of these findings, Zimbabweans are encouraged to cultivate an awareness that enables them to reflect on the challenges associated with diplomatic discourses and the implications for critically analysing the re-engagement initiative. They can promote re-engagement by being cognisant of specific values portrayed in The Herald and The Standard and challenging these values in the light of policy transformation to revive the relations between the two countries. The re-engagement process requires a transformation in Zimbabwe's modus operandi to improve the country's positioning in the diplomatic relations between it and the UK. , Thesis (PhD) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2023
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- Date Issued: 2023-10-13
An exploration into how Grade 3 Foundation Phase teachers implement differentiated instructional practices in their mathematics classrooms
- Authors: Jack, Nomzamo Bridget
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424057 , vital:72120
- Description: Today’s teaching space is more diverse than before. As a result, differentiated instruction is considered helpful in supporting learner diversity. This teaching approach considers socio-cultural, multiple intelligences, and learning styles also termed learning preferences of learners. It is against this view that I wanted to investigate the implementation of differentiated instruction teaching practices in the Foundation Phase. This study explored differentiated teaching strategies and procedures in mathematics teaching, and I observed four Grade 3 teachers. The theoretical framework underlying this study was the theory of practice architectures. This study is located within an interpretivist paradigm within which I employed a case study research design. The collection of the data sets was through observations and semi-structured interviews. For an analysis of observations, I used a deductive approach. On the other hand, for the semi-structured interviews, I use an inductive approach to discover patterns and themes that I applied during the data analysis process. The validation process was done by giving interview transcripts and a summary of discussions to respondents to verify their responses and check for any misinterpretations. Rich data sets were analysed concerning the research questions, which were as follows: What are the current differentiated instruction teaching practices used by Grade 3 Mathematics teachers? How can the teachers’ differentiated instruction teaching practices be understood in terms of doings, sayings and relatings? How are differentiated instruction teaching practices made visible through the lens of the Theory of Practice Architecture? The findings from the study revealed that the use of learners’ everyday language influences their understanding of mathematics terminology. The study discovered that learners were more comfortable using English to make sense of mathematics terms instead of using isiXhosa, the Language of Learning and Teaching in the Foundation Phase. Additionally, linking learning to learners’ everyday English language enabled them to learn mathematics terms in a relaxed and non-threatening situation, while isiXhosa seemed to constrain learning. Further, the findings revealed that teachers were unclear about differentiated instruction. That was evident when they did not know the elements of differentiated instruction. Thus, the study recommends that teachers need to be supported through workshops to enable them to enact differentiated instruction in their teaching. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Jack, Nomzamo Bridget
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424057 , vital:72120
- Description: Today’s teaching space is more diverse than before. As a result, differentiated instruction is considered helpful in supporting learner diversity. This teaching approach considers socio-cultural, multiple intelligences, and learning styles also termed learning preferences of learners. It is against this view that I wanted to investigate the implementation of differentiated instruction teaching practices in the Foundation Phase. This study explored differentiated teaching strategies and procedures in mathematics teaching, and I observed four Grade 3 teachers. The theoretical framework underlying this study was the theory of practice architectures. This study is located within an interpretivist paradigm within which I employed a case study research design. The collection of the data sets was through observations and semi-structured interviews. For an analysis of observations, I used a deductive approach. On the other hand, for the semi-structured interviews, I use an inductive approach to discover patterns and themes that I applied during the data analysis process. The validation process was done by giving interview transcripts and a summary of discussions to respondents to verify their responses and check for any misinterpretations. Rich data sets were analysed concerning the research questions, which were as follows: What are the current differentiated instruction teaching practices used by Grade 3 Mathematics teachers? How can the teachers’ differentiated instruction teaching practices be understood in terms of doings, sayings and relatings? How are differentiated instruction teaching practices made visible through the lens of the Theory of Practice Architecture? The findings from the study revealed that the use of learners’ everyday language influences their understanding of mathematics terminology. The study discovered that learners were more comfortable using English to make sense of mathematics terms instead of using isiXhosa, the Language of Learning and Teaching in the Foundation Phase. Additionally, linking learning to learners’ everyday English language enabled them to learn mathematics terms in a relaxed and non-threatening situation, while isiXhosa seemed to constrain learning. Further, the findings revealed that teachers were unclear about differentiated instruction. That was evident when they did not know the elements of differentiated instruction. Thus, the study recommends that teachers need to be supported through workshops to enable them to enact differentiated instruction in their teaching. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2023
- Full Text:
- Date Issued: 2023-10-13
An exploration of Black women’s motivations for pursuing sociology at Rhodes University
- Authors: Vezi, Indiphile Siyanda
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425220 , vital:72220
- Description: Enbargoed. Expected release date 2025. , Thesis (MA) -- Faculty of Humanities, Sociology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Vezi, Indiphile Siyanda
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425220 , vital:72220
- Description: Enbargoed. Expected release date 2025. , Thesis (MA) -- Faculty of Humanities, Sociology, 2023
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- Date Issued: 2023-10-13