Exploring resilience in undergraduate nursing students at a nursing education institution in the Eastern Cape, South Africa
- Authors: Blatti, Jenny
- Date: 2024-12
- Subjects: Nursing students -- South Africa -- Eastern Cape -- Psychology , Nursing -- Study and teaching -- South Africa , Nursing schools -- Faculty -- South Africa -- Eastern Cape
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69805 , vital:78036
- Description: Undergraduate nursing students worldwide experience stress and anxiety due to the demands of nursing education, which include challenges related to academic workloads and the clinical environment. This, in turn, may impede programme completion and continuation in nursing careers. Resilience is recognised as an effective attribute for nursing students in adapting to stressors and has been found to have a beneficial impact on learning experiences, academic performance, and professional practice. Despite numerous research studies conducted on resilience in the health professions, there remains little empirical work that has explored undergraduate nursing students' understanding and experience of their resilience. The purpose of this study was thus to explore undergraduate nursing students’ perceptions of their resilience at a nursing education institution in the Eastern Cape, South Africa, and to compile recommendations for a resilience training programme in undergraduate nursing education. A qualitative, explorative, descriptive, and contextual research design was implemented, with the study underpinned by the Resilience Ecological Stress Model. Third and fourth-year nursing students were recruited by purposive sampling, following which data was collected online by means of eleven individual semi-structured interviews conducted and recorded on the Microsoft (MS) Teams platform. Data was analysed using Braun and Clarke’s six steps of reflexive thematic analysis, generating codes and themes. The following themes were identified: participants’ perceptions of their challenges while studying nursing, participants’ understanding and experience of resilience, and participants’ views on the unique requirements of the degree in nursing. Findings indicated that nursing students perceive resilience as a beneficial attribute in mitigating the stress and anxiety evoked by their diverse challenges. Recommendations for nursing education were formulated based on the theoretical framework constructs and the findings of the study. , Thesis (MCur) -- Faculty of Health Sciences, School of Clinical Care & Medicinal Sciences, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Blatti, Jenny
- Date: 2024-12
- Subjects: Nursing students -- South Africa -- Eastern Cape -- Psychology , Nursing -- Study and teaching -- South Africa , Nursing schools -- Faculty -- South Africa -- Eastern Cape
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69805 , vital:78036
- Description: Undergraduate nursing students worldwide experience stress and anxiety due to the demands of nursing education, which include challenges related to academic workloads and the clinical environment. This, in turn, may impede programme completion and continuation in nursing careers. Resilience is recognised as an effective attribute for nursing students in adapting to stressors and has been found to have a beneficial impact on learning experiences, academic performance, and professional practice. Despite numerous research studies conducted on resilience in the health professions, there remains little empirical work that has explored undergraduate nursing students' understanding and experience of their resilience. The purpose of this study was thus to explore undergraduate nursing students’ perceptions of their resilience at a nursing education institution in the Eastern Cape, South Africa, and to compile recommendations for a resilience training programme in undergraduate nursing education. A qualitative, explorative, descriptive, and contextual research design was implemented, with the study underpinned by the Resilience Ecological Stress Model. Third and fourth-year nursing students were recruited by purposive sampling, following which data was collected online by means of eleven individual semi-structured interviews conducted and recorded on the Microsoft (MS) Teams platform. Data was analysed using Braun and Clarke’s six steps of reflexive thematic analysis, generating codes and themes. The following themes were identified: participants’ perceptions of their challenges while studying nursing, participants’ understanding and experience of resilience, and participants’ views on the unique requirements of the degree in nursing. Findings indicated that nursing students perceive resilience as a beneficial attribute in mitigating the stress and anxiety evoked by their diverse challenges. Recommendations for nursing education were formulated based on the theoretical framework constructs and the findings of the study. , Thesis (MCur) -- Faculty of Health Sciences, School of Clinical Care & Medicinal Sciences, 2024
- Full Text:
- Date Issued: 2024-12
Exploring the factors that influence productivity at the Ford Motor company engine plant in Gqeberha
- Authors: Reed, Ferdi
- Date: 2024-12
- Subjects: Ford Motor Company of South Africa , Industrial productivity , Automobile industry and trade -- Capital productivity -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69936 , vital:78244
- Description: This study examines productivity at the Ford Motor Company Engine Plant in Gqeberha, focusing on workplace challenges, employee morale, training programs, job flexibility, and leadership styles. The primary objective is to identify factors influencing productivity within this context, and the study aims to provide insights into improving employee engagement and operational efficiency. Conceptually, the research is underpinned by three main theories: the Theory of Constraints, Herzberg’s Two-Factor and Transformational Leadership. Together, these theories provided a comprehensive lens for analysing and addressing productivity dynamics at the Ford Motor Company Engine Plant in Gqeberha. The study utilised a qualitative research design using in-depth interviews as the data collection instrument. The qualitative data were analysed to find recurring themes about the perceptions of productivity at the plant. These results helped to provide a more nuanced understanding of how workers perceive the factors that determine productivity. The research findings highlighted several key factors impacting productivity. Effective leadership, especially transformational leadership, was shown to significantly enhance productivity by fostering a motivated and engaged workforce. Employee morale emerged as another crucial factor, with motivated and satisfied employees demonstrating higher productivity levels. A supportive work environment, along with opportunities for recognition and growth, was essential in maintaining high morale. Interviews with employees highlighted the critical role of effective leadership, particularly transformational leadership, in fostering a motivated and efficient workforce. Leaders who actively engage with their teams and provide clear guidance were found to enhance productivity significantly. Employee morale emerged as another crucial factor, with motivated and satisfied employees demonstrating higher productivity levels. The research underscored the importance of a supportive work environment, recognition, and growth opportunities in boosting employee morale. Training and development programs were also pivotal, with comprehensive training enhancing employee confidence and competence, leading to improved performance.Job flexibility, including flexible working hours and remote work options, was linked to better work-life balance, reduced burnout, and increased job satisfaction. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
Exploring the factors that influence productivity at the Ford Motor company engine plant in Gqeberha
- Authors: Reed, Ferdi
- Date: 2024-12
- Subjects: Ford Motor Company of South Africa , Industrial productivity , Automobile industry and trade -- Capital productivity -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69936 , vital:78244
- Description: This study examines productivity at the Ford Motor Company Engine Plant in Gqeberha, focusing on workplace challenges, employee morale, training programs, job flexibility, and leadership styles. The primary objective is to identify factors influencing productivity within this context, and the study aims to provide insights into improving employee engagement and operational efficiency. Conceptually, the research is underpinned by three main theories: the Theory of Constraints, Herzberg’s Two-Factor and Transformational Leadership. Together, these theories provided a comprehensive lens for analysing and addressing productivity dynamics at the Ford Motor Company Engine Plant in Gqeberha. The study utilised a qualitative research design using in-depth interviews as the data collection instrument. The qualitative data were analysed to find recurring themes about the perceptions of productivity at the plant. These results helped to provide a more nuanced understanding of how workers perceive the factors that determine productivity. The research findings highlighted several key factors impacting productivity. Effective leadership, especially transformational leadership, was shown to significantly enhance productivity by fostering a motivated and engaged workforce. Employee morale emerged as another crucial factor, with motivated and satisfied employees demonstrating higher productivity levels. A supportive work environment, along with opportunities for recognition and growth, was essential in maintaining high morale. Interviews with employees highlighted the critical role of effective leadership, particularly transformational leadership, in fostering a motivated and efficient workforce. Leaders who actively engage with their teams and provide clear guidance were found to enhance productivity significantly. Employee morale emerged as another crucial factor, with motivated and satisfied employees demonstrating higher productivity levels. The research underscored the importance of a supportive work environment, recognition, and growth opportunities in boosting employee morale. Training and development programs were also pivotal, with comprehensive training enhancing employee confidence and competence, leading to improved performance.Job flexibility, including flexible working hours and remote work options, was linked to better work-life balance, reduced burnout, and increased job satisfaction. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
Exploring the nature of the parent-child relationship and well- being of adolescents in families with a current history of maternal mental illness in a semi-urban area in East London, Eastern Cape
- Authors: Phakane, Siphokazi
- Date: 2024-12
- Subjects: Parent and child , Adolescent psychology , Mental illness
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69838 , vital:78039
- Description: Parent mental illness can detrimentally impact family functioning, thereby leading to increased conflicts, reduced adaptability, limited cohesion, and disorganised everyday planning (Smith, 2018). However, the specific effects of maternal mental illness on the relationship between mothers and adolescents, as well as on adolescent social and psychological development, remain unclear (Jones & Brown, 2020). This study aimed to explore and describe the nature of the parent-child relationship and the well-being of adolescents in families with a current history of maternal mental illness. Drawing from Bowlby's Ethological Theory of Attachment (1969) and from Ainsworth’s Attachment Theory (1970), qualitative research methods were employed to delve into these dynamics. The participants encompassed mothers aged between 30 to 60 with a current history of mental illness and adolescents aged between 15 to 18 residing with a mother with a current history of mental illness, and who is in remission. The study was conducted in a semi-urban area in East London, which is characterised by high unemployment rates, low education levels, and social stressors impacting mental health and family dynamics (Clark et al., 2019). Data collection involved face-to-face interviews, as well as utilising non-probability purposive and snowball sampling techniques. Braun and Clarke's (2006) framework was utilised for data interpretation, thus ensuring the adherence to the research ethics and to the trustworthiness standards as outlined by Lincoln and Guba (1985). The findings revealed both challenges and strengths in these families. The adolescents expressed concerns about the lack of parental support, coerced autonomy, and communication barriers. However, they also reported positive experiences of companionship and nurturing from their mothers. Emotional regulation difficulties and socio-economic challenges were prevalent, thus highlighting the need for tailored targeted support interventions to address the complex issues that are faced by the adolescents in the families which are affected by maternal mental illness. Overall, this research contributes to a deeper understanding of the nuanced , Thesis (MA) -- Faculty of Health Sciences, School of Behavioural & Lifestyle Sciences, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Phakane, Siphokazi
- Date: 2024-12
- Subjects: Parent and child , Adolescent psychology , Mental illness
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69838 , vital:78039
- Description: Parent mental illness can detrimentally impact family functioning, thereby leading to increased conflicts, reduced adaptability, limited cohesion, and disorganised everyday planning (Smith, 2018). However, the specific effects of maternal mental illness on the relationship between mothers and adolescents, as well as on adolescent social and psychological development, remain unclear (Jones & Brown, 2020). This study aimed to explore and describe the nature of the parent-child relationship and the well-being of adolescents in families with a current history of maternal mental illness. Drawing from Bowlby's Ethological Theory of Attachment (1969) and from Ainsworth’s Attachment Theory (1970), qualitative research methods were employed to delve into these dynamics. The participants encompassed mothers aged between 30 to 60 with a current history of mental illness and adolescents aged between 15 to 18 residing with a mother with a current history of mental illness, and who is in remission. The study was conducted in a semi-urban area in East London, which is characterised by high unemployment rates, low education levels, and social stressors impacting mental health and family dynamics (Clark et al., 2019). Data collection involved face-to-face interviews, as well as utilising non-probability purposive and snowball sampling techniques. Braun and Clarke's (2006) framework was utilised for data interpretation, thus ensuring the adherence to the research ethics and to the trustworthiness standards as outlined by Lincoln and Guba (1985). The findings revealed both challenges and strengths in these families. The adolescents expressed concerns about the lack of parental support, coerced autonomy, and communication barriers. However, they also reported positive experiences of companionship and nurturing from their mothers. Emotional regulation difficulties and socio-economic challenges were prevalent, thus highlighting the need for tailored targeted support interventions to address the complex issues that are faced by the adolescents in the families which are affected by maternal mental illness. Overall, this research contributes to a deeper understanding of the nuanced , Thesis (MA) -- Faculty of Health Sciences, School of Behavioural & Lifestyle Sciences, 2024
- Full Text:
- Date Issued: 2024-12
Extending psychological praxis within South Africa: exploring healers’ perceptions of treatment plurality
- Authors: Yew-Siong, Lauren
- Date: 2024-12
- Subjects: Traditional medicine -- South Africa , Psychology -- Africa , Clinical health psychology
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/69771 , vital:78032
- Description: The prevailing psychological praxis in South Africa predominantly follows western paradigms for defining, classifying, and diagnosing health and illness; falling short in encompassing the diverse mental healthcare reality. Scarce resources, inadequate infrastructure, and the interplay of religio-cultural beliefs intersect, shaping how psychological disturbances are perceived and how treatment is sought- especially for patients who do not ascribe to one treatment modality, or one paradigm. Therefore, this study explored ideas and notions surrounding treatment plurality held by healers (that being psychologists, psychiatrists, and traditional healers), within the South African context. The research utilised a qualitative exploratory-descriptive research methodology with a phenomenological research design. The researcher then employed purposive and snowball sampling to recruit participants. Thereafter, the researcher conducted online semi-structured interviews, and applied Braun and Clarke's (2006) thematic analysis to analyse the data. The following themes were then unpacked: 1) Healers’ perceptions of treatment plurality; 2) The need for collaboration between various disciplines; 3) Education as a key factor in pluralism; 4) Healer ethics and malpractice; 5) The lack of governmental funding and resources. The results suggest the need for a pluralistic mental healthcare approach in South Africa, bridging western and traditional practices. Yet, challenges stemming from inadequate governmental funding, resources, policies, and ethical guidelines hinder its development and implementation. Therefore, it would take more than one set of guidelines to implement pluralistic treatment within South African mental healthcare. For this purpose, the researcher decided to create a blueprint for various developments that is needed to make a pluralistic approach a reality in South Africa. These findings encouraged the researcher to develop: 1) Guidelines for the Provision of Collaborative Care in Mental Healthcare Services; 2) Guidelines for South African governmental policy that foster pluralism and collaborative care in the mental healthcare system; 3) A pluralistic medical aid scheme; 4) A module blueprint that could potentially be included in a professional master’s programme, as well as the inclusion of a theory the researcher has developed, named the Pluralism-oriented Mental Healthcare Theory. , Thesis (PhD) -- Faculty of Health Sciences, School of Behavioural & Lifestyle Sciences, 2023
- Full Text:
- Date Issued: 2024-12
- Authors: Yew-Siong, Lauren
- Date: 2024-12
- Subjects: Traditional medicine -- South Africa , Psychology -- Africa , Clinical health psychology
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/69771 , vital:78032
- Description: The prevailing psychological praxis in South Africa predominantly follows western paradigms for defining, classifying, and diagnosing health and illness; falling short in encompassing the diverse mental healthcare reality. Scarce resources, inadequate infrastructure, and the interplay of religio-cultural beliefs intersect, shaping how psychological disturbances are perceived and how treatment is sought- especially for patients who do not ascribe to one treatment modality, or one paradigm. Therefore, this study explored ideas and notions surrounding treatment plurality held by healers (that being psychologists, psychiatrists, and traditional healers), within the South African context. The research utilised a qualitative exploratory-descriptive research methodology with a phenomenological research design. The researcher then employed purposive and snowball sampling to recruit participants. Thereafter, the researcher conducted online semi-structured interviews, and applied Braun and Clarke's (2006) thematic analysis to analyse the data. The following themes were then unpacked: 1) Healers’ perceptions of treatment plurality; 2) The need for collaboration between various disciplines; 3) Education as a key factor in pluralism; 4) Healer ethics and malpractice; 5) The lack of governmental funding and resources. The results suggest the need for a pluralistic mental healthcare approach in South Africa, bridging western and traditional practices. Yet, challenges stemming from inadequate governmental funding, resources, policies, and ethical guidelines hinder its development and implementation. Therefore, it would take more than one set of guidelines to implement pluralistic treatment within South African mental healthcare. For this purpose, the researcher decided to create a blueprint for various developments that is needed to make a pluralistic approach a reality in South Africa. These findings encouraged the researcher to develop: 1) Guidelines for the Provision of Collaborative Care in Mental Healthcare Services; 2) Guidelines for South African governmental policy that foster pluralism and collaborative care in the mental healthcare system; 3) A pluralistic medical aid scheme; 4) A module blueprint that could potentially be included in a professional master’s programme, as well as the inclusion of a theory the researcher has developed, named the Pluralism-oriented Mental Healthcare Theory. , Thesis (PhD) -- Faculty of Health Sciences, School of Behavioural & Lifestyle Sciences, 2023
- Full Text:
- Date Issued: 2024-12
Factors affecting consumer purchase intentions towards traditional small grain foods in Zimbabwe
- Authors: Moyo, Arnold
- Date: 2024-12
- Subjects: Consumer behavior -- Zimbabwe , Consumer satisfaction -- Zimbabwe , Consumers' preferences -- Zimbabwe
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/70067 , vital:78289
- Description: The consumption of traditional small grain foods in Zimbabwe is low and declining. This trend persists despite their nutritional, economic, socio-cultural and environmental benefits. Increasing the consumer demand for traditional small grain foods in Zimbabwe requires empirically based marketing interventions, which, in turn, rely on a holistic understanding of the factors affecting traditional small grain food consumption in the country. However, consumer-focused research that aims to stimulate consumer purchase intentions is both sparse and fragmented. This study addresses this sparsity and fragmentation of research by exploring multiple factors affecting consumer purchase intentions towards traditional small grain foods in Zimbabwe. The overarching purpose of the study was to enhance the understanding of context-specific factors affecting consumer purchase intentions towards traditional small grain foods in Zimbabwe. Pursuant to this aim, four objectives were developed. These are: (i) to identify relevant personal, environmental and food-related factors affecting consumer purchase intentions towards traditional small grain foods; (ii) to examine the extent to which identified factors affect consumer purchase intentions towards traditional small grain foods in Zimbabwe; (iii) to propose an integrated model to guide marketing practitioners and retailers on how to design marketing interventions that stimulate consumer purchase intentions towards traditional small grain foods; and (iv) to recommend marketing strategies that retailers and traditional food marketers could implement to promote consumer purchase intentions towards traditional small grain foods in Zimbabwe. Informed by the stated objectives, the study embraced a positivist paradigm and descriptive design. The hypothesised framework of the study was premised on integrating the Food Preference and Consumption Model, the Consumer Behaviour Model with respect to food and the Theory of Planned Behaviour. Primary data were collected through a survey of 386 respondents selected from Zimbabwe's 10 provinces using quota sampling at the provincial level based on each province's contribution to the national population of 15,178,957. Convenience sampling was used within each province. Data analysis was conducted using IBM SPSS v.26 for covariance-based structural equation modelling and SmartPLS 4 for partial least squares-based structural equation modelling, which was a double-quantitative complementary triangulation approach and was a novel methodology in consumer behaviour studies relating to traditional foods. Ten context-relevant factors affecting consumer purchase intentions were identified, seven of which had a significant influence on purchase intentions. Analysed data led to the development, testing and validation of two novel, explanatory, predictive and context-specific models for consumer purchase intentions towards traditional small grain foods in Zimbabwe (the lower-order component and higher-order component Traditional Small Grain Food Preference models). The study contributes a new measurement instrument and model to consumer behaviour literature, particularly in Africa where related research is sparce. The study makes an additional theoretical contribution by utilising a double quantitative complementary triangulation method of data analysis. Results of the study enables marketers to optimise their resource allocation by prioritising the most influential determinants of consumer purchase intentions. Results on significant demographic differences in purchase intentions demonstrated the need for a more targeted, segmentation-driven approach to marketing strategy formulation by tailoring the marketing mix, communication message and channels and positioning strategies, to the unique needs and preferences of distinct consumer segments. , Thesis (PhD) -- Faculty of Business and Economic Sciences, School of Management Sciences, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Moyo, Arnold
- Date: 2024-12
- Subjects: Consumer behavior -- Zimbabwe , Consumer satisfaction -- Zimbabwe , Consumers' preferences -- Zimbabwe
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/70067 , vital:78289
- Description: The consumption of traditional small grain foods in Zimbabwe is low and declining. This trend persists despite their nutritional, economic, socio-cultural and environmental benefits. Increasing the consumer demand for traditional small grain foods in Zimbabwe requires empirically based marketing interventions, which, in turn, rely on a holistic understanding of the factors affecting traditional small grain food consumption in the country. However, consumer-focused research that aims to stimulate consumer purchase intentions is both sparse and fragmented. This study addresses this sparsity and fragmentation of research by exploring multiple factors affecting consumer purchase intentions towards traditional small grain foods in Zimbabwe. The overarching purpose of the study was to enhance the understanding of context-specific factors affecting consumer purchase intentions towards traditional small grain foods in Zimbabwe. Pursuant to this aim, four objectives were developed. These are: (i) to identify relevant personal, environmental and food-related factors affecting consumer purchase intentions towards traditional small grain foods; (ii) to examine the extent to which identified factors affect consumer purchase intentions towards traditional small grain foods in Zimbabwe; (iii) to propose an integrated model to guide marketing practitioners and retailers on how to design marketing interventions that stimulate consumer purchase intentions towards traditional small grain foods; and (iv) to recommend marketing strategies that retailers and traditional food marketers could implement to promote consumer purchase intentions towards traditional small grain foods in Zimbabwe. Informed by the stated objectives, the study embraced a positivist paradigm and descriptive design. The hypothesised framework of the study was premised on integrating the Food Preference and Consumption Model, the Consumer Behaviour Model with respect to food and the Theory of Planned Behaviour. Primary data were collected through a survey of 386 respondents selected from Zimbabwe's 10 provinces using quota sampling at the provincial level based on each province's contribution to the national population of 15,178,957. Convenience sampling was used within each province. Data analysis was conducted using IBM SPSS v.26 for covariance-based structural equation modelling and SmartPLS 4 for partial least squares-based structural equation modelling, which was a double-quantitative complementary triangulation approach and was a novel methodology in consumer behaviour studies relating to traditional foods. Ten context-relevant factors affecting consumer purchase intentions were identified, seven of which had a significant influence on purchase intentions. Analysed data led to the development, testing and validation of two novel, explanatory, predictive and context-specific models for consumer purchase intentions towards traditional small grain foods in Zimbabwe (the lower-order component and higher-order component Traditional Small Grain Food Preference models). The study contributes a new measurement instrument and model to consumer behaviour literature, particularly in Africa where related research is sparce. The study makes an additional theoretical contribution by utilising a double quantitative complementary triangulation method of data analysis. Results of the study enables marketers to optimise their resource allocation by prioritising the most influential determinants of consumer purchase intentions. Results on significant demographic differences in purchase intentions demonstrated the need for a more targeted, segmentation-driven approach to marketing strategy formulation by tailoring the marketing mix, communication message and channels and positioning strategies, to the unique needs and preferences of distinct consumer segments. , Thesis (PhD) -- Faculty of Business and Economic Sciences, School of Management Sciences, 2024
- Full Text:
- Date Issued: 2024-12
Factors affecting the selection of customs brokerage service providers in the automotive manufacturing industry of South Africa
- Authors: Taai, Eric
- Date: 2024-12
- Subjects: International trade , Foreign trade regulation -- South Africa , Automobile industry and trade -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69902 , vital:78171
- Description: Any firm participating in the import and export of goods needs to be aware of the customs and tax implications of these activities. Few firms have internal staff who are qualified in this area; thus, they tend to outsource this function to external Customs Brokerage Service providers who can submit customs declarations on behalf of traders to Customs for their imported or exported goods. The main aim of this study was to identify how firms choose their preferred Customs Brokerage Service since these external service providers play a critical role in the efficient and effective functioning of firms relying on imports and exports as part of their logistics value chain. The study sought to identify which key factors influenced the selection of a customs broker. The main research question was: What are the factors that should be considered when selecting a customs brokerage service provider in the South African automotive manufacturing industry? Forty-one respondents participated in this study. This research study undertook positivistic research using quantitative methods of analysis based on the statistical examination of quantitative research data. The quantitative processes of this research study are comprehensively explored in Chapter 3. The main results of this study statistically identified the following independent factors influencing Customs Broker selection: Cost of Service, Relationship Orientation, Technological System, Key Performance Indicators, and Size, as each factor exhibits a significantly positive effect on Customs Broker selection. This study has surveyed, identified, and established these factors that the South African automotive manufacturers should consider when selecting a customs broker service provider. The number of customs experts, consultants, and specialists was firmly confirmed as an important aspect to consider under the factor Size of a Customs Broker. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Taai, Eric
- Date: 2024-12
- Subjects: International trade , Foreign trade regulation -- South Africa , Automobile industry and trade -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69902 , vital:78171
- Description: Any firm participating in the import and export of goods needs to be aware of the customs and tax implications of these activities. Few firms have internal staff who are qualified in this area; thus, they tend to outsource this function to external Customs Brokerage Service providers who can submit customs declarations on behalf of traders to Customs for their imported or exported goods. The main aim of this study was to identify how firms choose their preferred Customs Brokerage Service since these external service providers play a critical role in the efficient and effective functioning of firms relying on imports and exports as part of their logistics value chain. The study sought to identify which key factors influenced the selection of a customs broker. The main research question was: What are the factors that should be considered when selecting a customs brokerage service provider in the South African automotive manufacturing industry? Forty-one respondents participated in this study. This research study undertook positivistic research using quantitative methods of analysis based on the statistical examination of quantitative research data. The quantitative processes of this research study are comprehensively explored in Chapter 3. The main results of this study statistically identified the following independent factors influencing Customs Broker selection: Cost of Service, Relationship Orientation, Technological System, Key Performance Indicators, and Size, as each factor exhibits a significantly positive effect on Customs Broker selection. This study has surveyed, identified, and established these factors that the South African automotive manufacturers should consider when selecting a customs broker service provider. The number of customs experts, consultants, and specialists was firmly confirmed as an important aspect to consider under the factor Size of a Customs Broker. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
Failure of autonomous maintenance program at the Gqeberha food manufacturing plant
- Authors: Moloi, Tshepo
- Date: 2024-12
- Subjects: Automatic control , Process control , Food industry and trade -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/70078 , vital:78290
- Description: The main emphasis of this research is on the identification of the main factors explaining the difficulties and failure of Autonomous Maintenance (AM) program implementation from the year 2018 to 2024. This qualitative study focuses on a Port Elizabeth, South Africa food processing company that has implemented an AM program. The lack of success attained in staff training after the implementation phase drove this investigation. This study was carried out to provide first-hand evidence of the pragmatic difficulties in the execution of the AM program. Three main goals defined the research: first, to find the problems that emerged during the AM implementation; second, to investigate the inadequacy of the training program in equipping workers with the necessary skills and competencies to successfully carry out AM; and thirdly, to get valuable opinions on possible enhancements or alternative approaches to the implementation phase of AM from operators, line leaders, and analysts. There is an existing research vacuum as nothing is known about how training affects the implementation of AM in food processing plants especially in South Africa. Purposive sampling selected thirty persons. Thirteen process operators, nine technical operators, six-line leaders, two preventive maintenance owners, and a senior management representative made comprised the group. Extensive in-person interviews with operators, line leaders, and top management gathered the data. Thematic analysis was used to examine the data even further to pinpoint the main themes that emerged. Six main topics found in this research best capture the difficulties faced by a food processing company using AM. The problems were poor training, limited time and resources, lack of motivation and rewards, ineffective communication, involvement, and accountability; management gave production priority over autonomous maintenance; and there was no culture of dedication. Several factors contribute to the ineffectiveness of the training program in enabling employees with the required skills to implement AM: the lack of practical examples to support theoretical ideas, limited resources, trainers lacking expertise in their respective fields, which limits understanding. The main emphasis of this research is on the identification of the main factors explaining the difficulties throughout the implementation period. Moreover, this research improves the body of information already in use by stressing the inadequacies of the training program in developing important skills. Helping AM operators and line supervisors understand the difficulties they faced is the primary goal of the research. Top executives will be offered the recommendations for improving and maximizing the AM program. Understanding the training needs for operators will help production managers and human resources professionals to guarantee their successful training and efficient application of the program. Operations management experts in academia have thorough understanding of AM including theoretical ideas, pragmatic implementation, and the difficulties using successful strategies. The key limitation was the narrow focus of the research, which mainly looked at people within the production line of the model line to understand the problems that emerged during the implementation of autonomous maintenance. The generalisation of the results to the whole workforce is not achieved due to the exclusion of employees from other areas of the factory. The company wants to start a thorough training program with a cross-functional team to enhance operator communication. The main topics explaining the problems in the training program is another disadvantage. This will be a strong basis for further studies. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Moloi, Tshepo
- Date: 2024-12
- Subjects: Automatic control , Process control , Food industry and trade -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/70078 , vital:78290
- Description: The main emphasis of this research is on the identification of the main factors explaining the difficulties and failure of Autonomous Maintenance (AM) program implementation from the year 2018 to 2024. This qualitative study focuses on a Port Elizabeth, South Africa food processing company that has implemented an AM program. The lack of success attained in staff training after the implementation phase drove this investigation. This study was carried out to provide first-hand evidence of the pragmatic difficulties in the execution of the AM program. Three main goals defined the research: first, to find the problems that emerged during the AM implementation; second, to investigate the inadequacy of the training program in equipping workers with the necessary skills and competencies to successfully carry out AM; and thirdly, to get valuable opinions on possible enhancements or alternative approaches to the implementation phase of AM from operators, line leaders, and analysts. There is an existing research vacuum as nothing is known about how training affects the implementation of AM in food processing plants especially in South Africa. Purposive sampling selected thirty persons. Thirteen process operators, nine technical operators, six-line leaders, two preventive maintenance owners, and a senior management representative made comprised the group. Extensive in-person interviews with operators, line leaders, and top management gathered the data. Thematic analysis was used to examine the data even further to pinpoint the main themes that emerged. Six main topics found in this research best capture the difficulties faced by a food processing company using AM. The problems were poor training, limited time and resources, lack of motivation and rewards, ineffective communication, involvement, and accountability; management gave production priority over autonomous maintenance; and there was no culture of dedication. Several factors contribute to the ineffectiveness of the training program in enabling employees with the required skills to implement AM: the lack of practical examples to support theoretical ideas, limited resources, trainers lacking expertise in their respective fields, which limits understanding. The main emphasis of this research is on the identification of the main factors explaining the difficulties throughout the implementation period. Moreover, this research improves the body of information already in use by stressing the inadequacies of the training program in developing important skills. Helping AM operators and line supervisors understand the difficulties they faced is the primary goal of the research. Top executives will be offered the recommendations for improving and maximizing the AM program. Understanding the training needs for operators will help production managers and human resources professionals to guarantee their successful training and efficient application of the program. Operations management experts in academia have thorough understanding of AM including theoretical ideas, pragmatic implementation, and the difficulties using successful strategies. The key limitation was the narrow focus of the research, which mainly looked at people within the production line of the model line to understand the problems that emerged during the implementation of autonomous maintenance. The generalisation of the results to the whole workforce is not achieved due to the exclusion of employees from other areas of the factory. The company wants to start a thorough training program with a cross-functional team to enhance operator communication. The main topics explaining the problems in the training program is another disadvantage. This will be a strong basis for further studies. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
Formulation of Fish Feed for Aquaculture using Olive Pomace Extract as an Antioxidant
- Authors: Koza, Nondumiso Norma
- Date: 2024-12
- Subjects: Fishes -- Feeding and feeds , Fishes -- Ecology , Sustainable aquaculture
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69318 , vital:77205
- Description: Olive pomace is a significant by-product of the olive oil extraction process and is an environmental issue in olive-producing countries. This project aimed to add extracts from olive pomace as an antioxidant to a fish feed formulation without compromising growth performance and meat quality, thereby contributing to the aquaculture industry. To produce the olive pomace extracts, Coratina cultivar olives were collected from a farm near Oudtshoorn, and the fresh pomace was immediately frozen at -22oC for preservation. The extracts were obtained using a large-scale extraction method using a solvent blend of n-heptane, ethanol, and water. A pressure filtration and centrifuge method were then applied to separate any residue from the extracts. An HPLC method was developed to characterise the extracts' content, identifying various bioactive compounds such as squalene, α-tocopherol, and water-soluble polyphenols like oleuropein, hydroxytyrosol, and tyrosol. In a fish feeding trial it was concluded that the fish fed with the feed without olive pomace gained more weight than those fed the feed with the added pomace extract. Overall, the results indicate that fish sustained on the feed without the olive pomace extract ate more food, consuming more energy to support weight gain but that this did not necessarily translate to an improved feed conversion ratio. The morphometric variables suggest that fish used in the trial remained healthy, implying that there may be a taste or palatability difference between feeds that could explain why less of the feed with olive pomace extract was eaten. Overall, the observed feed conversion ratio values were somewhat lower than the expected values for tilapia (FCR: 1.5-2.0). The peroxide value of fish feed with an addition of 0.3% olive pomace extract was lower than that of the feed without olive pomace extract after 12 weeks of stability testing at room temperature. The results showed a value of 1.48 MeqO2/kg for the feed containing olive pomace extract compared to the peroxide value for the fish feed without olive pomace extract, which was 2.75 MeqO2/kg. This indicates that the nutritional content of the feed was preserved. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Koza, Nondumiso Norma
- Date: 2024-12
- Subjects: Fishes -- Feeding and feeds , Fishes -- Ecology , Sustainable aquaculture
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69318 , vital:77205
- Description: Olive pomace is a significant by-product of the olive oil extraction process and is an environmental issue in olive-producing countries. This project aimed to add extracts from olive pomace as an antioxidant to a fish feed formulation without compromising growth performance and meat quality, thereby contributing to the aquaculture industry. To produce the olive pomace extracts, Coratina cultivar olives were collected from a farm near Oudtshoorn, and the fresh pomace was immediately frozen at -22oC for preservation. The extracts were obtained using a large-scale extraction method using a solvent blend of n-heptane, ethanol, and water. A pressure filtration and centrifuge method were then applied to separate any residue from the extracts. An HPLC method was developed to characterise the extracts' content, identifying various bioactive compounds such as squalene, α-tocopherol, and water-soluble polyphenols like oleuropein, hydroxytyrosol, and tyrosol. In a fish feeding trial it was concluded that the fish fed with the feed without olive pomace gained more weight than those fed the feed with the added pomace extract. Overall, the results indicate that fish sustained on the feed without the olive pomace extract ate more food, consuming more energy to support weight gain but that this did not necessarily translate to an improved feed conversion ratio. The morphometric variables suggest that fish used in the trial remained healthy, implying that there may be a taste or palatability difference between feeds that could explain why less of the feed with olive pomace extract was eaten. Overall, the observed feed conversion ratio values were somewhat lower than the expected values for tilapia (FCR: 1.5-2.0). The peroxide value of fish feed with an addition of 0.3% olive pomace extract was lower than that of the feed without olive pomace extract after 12 weeks of stability testing at room temperature. The results showed a value of 1.48 MeqO2/kg for the feed containing olive pomace extract compared to the peroxide value for the fish feed without olive pomace extract, which was 2.75 MeqO2/kg. This indicates that the nutritional content of the feed was preserved. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-12
Graphene@microalgae-based nanohybrid structures as adsorbents for removal of Cr(VI) ions in aqueous solutions
- Authors: Mulovhedzi, Rolivhuwa
- Date: 2024-12
- Subjects: Nanoscience , Nanotechnology , Nonaqueous solvents
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69404 , vital:77252
- Description: iv ABSTRACT The efficient removal of heavy metals using carbon-based nanoadsorbents poses a substantial challenge in the domain of water purification. Graphene-based materials have been extensively utilised in the treatment of water and wastewater due to their tremendous surface areas, porosity, turntable nature to different functional groups, and photo-catalytic properties. In this project, graphene oxide (GO) was synthesised via the modified Hummers method. A similar method was used to produce nitrogen-doped graphene oxide (NGO), with urea as the nitrogen precursor. Utilising biomass materials to dope graphene-based nanocomposites can effectively enhance their application in water treatment. In this work, graphene oxide-microalgae (GO@Algae) and N-doped graphene oxide-microalgae (NGO@Algae) nanocomposites were synthesised by combining GO or NGO with green Scenedesmus microalgae. This was done through a solution self-assembly mixing method using ultrasonication. The resulting nanocomposites were used to remove Cr(VI) from water solutions. The influence of microalgae content deposited on GO and NGO nanosheets at different weight ratios (1:1, 3:1, and 1:3) on the chemical, structural, morphological, and thermal characteristics of nanoadsorbents was evaluated using various techniques such as Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The flat nanosheet-like morphology of GO@Algae and NGO@Algae nanostructured materials was observed through SEM, confirming microalgae's incorporation within the GO and NGO matrices. The thermal stability and surface area properties of GO and NGO nanocomposite materials decreased with the incorporation of microalgae content. The incorporation of microalgae into GO nanosheets showed enhancements in chemical and structural properties due to the presence of the strong covalent interaction (oxygen and nitrogen-containing groups) between the interfaces of nanocomposites. XPS and FT-IR analyses revealed the existence of amides, carboxylic acids, and phosphates, which exhibited positive charges below the pH 2.03 point-of-zero charge. The second phase of the study involved assessing the adsorption capabilities of the GO, NGO nanosheets, and GO@Algae and NGO@Algae nanocomposites in removing Cr(VI)from the water solution. Adsorption parameters such as the effect of solution pH, contact time, adsorbent dosage and metal ion concentrations were evaluated for Cr(VI) removal. When comparing GO, NGO, GO@Algae, and NGO@Algae, it was found that GO@Algae and NGO@Algae exhibited superior adsorption performance due to the available functional groups and well-developed pores. Additionally, a mixed ratio of GO or NGO and algae at a ratio of 1:3 was found to be the most suitable for GO@Algae and NGO@Algae. The adsorption efficiency of nanostructured materials for Cr(VI) is significantly influenced by their surface charge, porosity and specific surface area. The results revealed that the adsorption capabilities of GO@Algae (1:3) and NGO@Algae (1:3) were 2.24 and 2.01 times higher than GO and NGO which were 1.64 and 1.89, respectively, at a solution of pH 2 where HCrO4− species are predominant compared to a solution of pH 5 which predominate a mix of Cr2O72− and CrO42- species. The enhanced performance of the GO@Algae and NGO@Algae nanocomposites is attributed due to their increased surface functionalities and porosity. The adsorption of Cr(VI) ions by the GO/NGO@Algae nanocomposites declined with increasing initial concentration of Cr(VI) species in the water medium. The adsorption kinetics data for GO, NGO, GO@Algae (1:3), and NGO@Algae (1:3) exhibited a good fit with the pseudo-second-order model (R2 > 0.995) suggesting that chemisorption governed the adsorption process. Similarly, the isotherm adsorption findings showed a good fit with the Freundlich model (R2 > 0.961). The findings indicated that the adsorption mechanism process was characterised by monolayer adsorption onto a heterogeneous adsorbent surface. Furthermore, the GO@Algae (1:3) was found to have the maximum adsorption capacity of 10.85 mg/g surpassing the capacities of both unmodified and NGO@Algae counterparts. The application of GO@Algae and NGO@Algae has the potential to promote the green reuse of graphene-based nanomaterials. In summary, GO@Algae and NGO@Algae show great potential as eco-friendly adsorbents for the feasible treatment of heavy metal-contaminated water. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Mulovhedzi, Rolivhuwa
- Date: 2024-12
- Subjects: Nanoscience , Nanotechnology , Nonaqueous solvents
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69404 , vital:77252
- Description: iv ABSTRACT The efficient removal of heavy metals using carbon-based nanoadsorbents poses a substantial challenge in the domain of water purification. Graphene-based materials have been extensively utilised in the treatment of water and wastewater due to their tremendous surface areas, porosity, turntable nature to different functional groups, and photo-catalytic properties. In this project, graphene oxide (GO) was synthesised via the modified Hummers method. A similar method was used to produce nitrogen-doped graphene oxide (NGO), with urea as the nitrogen precursor. Utilising biomass materials to dope graphene-based nanocomposites can effectively enhance their application in water treatment. In this work, graphene oxide-microalgae (GO@Algae) and N-doped graphene oxide-microalgae (NGO@Algae) nanocomposites were synthesised by combining GO or NGO with green Scenedesmus microalgae. This was done through a solution self-assembly mixing method using ultrasonication. The resulting nanocomposites were used to remove Cr(VI) from water solutions. The influence of microalgae content deposited on GO and NGO nanosheets at different weight ratios (1:1, 3:1, and 1:3) on the chemical, structural, morphological, and thermal characteristics of nanoadsorbents was evaluated using various techniques such as Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The flat nanosheet-like morphology of GO@Algae and NGO@Algae nanostructured materials was observed through SEM, confirming microalgae's incorporation within the GO and NGO matrices. The thermal stability and surface area properties of GO and NGO nanocomposite materials decreased with the incorporation of microalgae content. The incorporation of microalgae into GO nanosheets showed enhancements in chemical and structural properties due to the presence of the strong covalent interaction (oxygen and nitrogen-containing groups) between the interfaces of nanocomposites. XPS and FT-IR analyses revealed the existence of amides, carboxylic acids, and phosphates, which exhibited positive charges below the pH 2.03 point-of-zero charge. The second phase of the study involved assessing the adsorption capabilities of the GO, NGO nanosheets, and GO@Algae and NGO@Algae nanocomposites in removing Cr(VI)from the water solution. Adsorption parameters such as the effect of solution pH, contact time, adsorbent dosage and metal ion concentrations were evaluated for Cr(VI) removal. When comparing GO, NGO, GO@Algae, and NGO@Algae, it was found that GO@Algae and NGO@Algae exhibited superior adsorption performance due to the available functional groups and well-developed pores. Additionally, a mixed ratio of GO or NGO and algae at a ratio of 1:3 was found to be the most suitable for GO@Algae and NGO@Algae. The adsorption efficiency of nanostructured materials for Cr(VI) is significantly influenced by their surface charge, porosity and specific surface area. The results revealed that the adsorption capabilities of GO@Algae (1:3) and NGO@Algae (1:3) were 2.24 and 2.01 times higher than GO and NGO which were 1.64 and 1.89, respectively, at a solution of pH 2 where HCrO4− species are predominant compared to a solution of pH 5 which predominate a mix of Cr2O72− and CrO42- species. The enhanced performance of the GO@Algae and NGO@Algae nanocomposites is attributed due to their increased surface functionalities and porosity. The adsorption of Cr(VI) ions by the GO/NGO@Algae nanocomposites declined with increasing initial concentration of Cr(VI) species in the water medium. The adsorption kinetics data for GO, NGO, GO@Algae (1:3), and NGO@Algae (1:3) exhibited a good fit with the pseudo-second-order model (R2 > 0.995) suggesting that chemisorption governed the adsorption process. Similarly, the isotherm adsorption findings showed a good fit with the Freundlich model (R2 > 0.961). The findings indicated that the adsorption mechanism process was characterised by monolayer adsorption onto a heterogeneous adsorbent surface. Furthermore, the GO@Algae (1:3) was found to have the maximum adsorption capacity of 10.85 mg/g surpassing the capacities of both unmodified and NGO@Algae counterparts. The application of GO@Algae and NGO@Algae has the potential to promote the green reuse of graphene-based nanomaterials. In summary, GO@Algae and NGO@Algae show great potential as eco-friendly adsorbents for the feasible treatment of heavy metal-contaminated water. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-12
Ground- and marine water inputs into supratidal microbialite systems along the Nelson Mandela Bay coastline
- Authors: O’Connell, Tristin Wade
- Date: 2024-12
- Subjects: Groundwater -- South Africa -- Nelson Mandela Bay , Earth sciences , Geology
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69415 , vital:77253
- Description: Extant supratidal microbialite systems are especially numerous and well-developed along the rocky coastline of Nelson Mandela Bay (NMB), South Africa. Precipitating in a hydrological environment formed by the input of constant, fresh groundwater discharge and periodic marine water intrusion these systems form part of the longest uninterrupted geological record of life on Earth (~3.4 billion years ago). Microbialites are layered organosedimentary deposits which potentially provide a window into historical environmental conditions. This study focusses on the fresh groundwater and saline marine water inputs of these microbialite pools, and the corresponding microbialite accretion rates. Severe regional drought in the NMB area resulted in rapid anthropogenic groundwater abstraction of the coastal aquifers on which the microbialite systems rely for groundwater inflow. This study provides insight into the current state of the coastal aquifers of NMB through the quantification of groundwater discharge via microbialite systems in terms of volume and flow rate. This is paired with in situ hourly microbialite pool water temperature and conductivity data to determine the effect of marine intrusion and the role of tidal flushing in these pools. A spatial assessment of groundwater discharge conducted using quantitative and semi-quantitative measurement techniques indicated that the total discharge of the study area is ~45.8 L/s or 3.8 ML/d. Over 1,500 freshwater seeps were identified, of which 78% showed microbialite deposits. Topography of the coast indicated that this might influence the flowrate. Calcareous sediment of sandy beaches within the study area supported lower discharge, while rocky shores with lithified rock had higher discharge. Seasonal differences in the volume discharged were evident, with winter having higher flowrates. Flow paths and discharge rates are affected by inland lithological differences and indicate variability linked to rainfall events that show lag effects depending on aquifer origins. This study is the first spatial analysis of the volume of groundwater discharging through microbialite-fed seeps. Marine intrusion and the corresponding pool flushing dynamics identified three types of microbailite systems: groundwater-dominant, dynamic input, and fast-reacting sites. A novel measurement technique for microbialite accretion determined accretion rates for systems under varying pool conditions. Although the average accretion rates of the Nelson Mandela Bay microbialites were in the order of erosion of 0.35 mm per year, there was significant variability in these measurements likely linked to differential localised vulnerability to storm events or responses to groundwater ix flow variability. It remains to be determined whether these factors are definitive risks to the sensitive supratidal microbialite systems. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: O’Connell, Tristin Wade
- Date: 2024-12
- Subjects: Groundwater -- South Africa -- Nelson Mandela Bay , Earth sciences , Geology
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69415 , vital:77253
- Description: Extant supratidal microbialite systems are especially numerous and well-developed along the rocky coastline of Nelson Mandela Bay (NMB), South Africa. Precipitating in a hydrological environment formed by the input of constant, fresh groundwater discharge and periodic marine water intrusion these systems form part of the longest uninterrupted geological record of life on Earth (~3.4 billion years ago). Microbialites are layered organosedimentary deposits which potentially provide a window into historical environmental conditions. This study focusses on the fresh groundwater and saline marine water inputs of these microbialite pools, and the corresponding microbialite accretion rates. Severe regional drought in the NMB area resulted in rapid anthropogenic groundwater abstraction of the coastal aquifers on which the microbialite systems rely for groundwater inflow. This study provides insight into the current state of the coastal aquifers of NMB through the quantification of groundwater discharge via microbialite systems in terms of volume and flow rate. This is paired with in situ hourly microbialite pool water temperature and conductivity data to determine the effect of marine intrusion and the role of tidal flushing in these pools. A spatial assessment of groundwater discharge conducted using quantitative and semi-quantitative measurement techniques indicated that the total discharge of the study area is ~45.8 L/s or 3.8 ML/d. Over 1,500 freshwater seeps were identified, of which 78% showed microbialite deposits. Topography of the coast indicated that this might influence the flowrate. Calcareous sediment of sandy beaches within the study area supported lower discharge, while rocky shores with lithified rock had higher discharge. Seasonal differences in the volume discharged were evident, with winter having higher flowrates. Flow paths and discharge rates are affected by inland lithological differences and indicate variability linked to rainfall events that show lag effects depending on aquifer origins. This study is the first spatial analysis of the volume of groundwater discharging through microbialite-fed seeps. Marine intrusion and the corresponding pool flushing dynamics identified three types of microbailite systems: groundwater-dominant, dynamic input, and fast-reacting sites. A novel measurement technique for microbialite accretion determined accretion rates for systems under varying pool conditions. Although the average accretion rates of the Nelson Mandela Bay microbialites were in the order of erosion of 0.35 mm per year, there was significant variability in these measurements likely linked to differential localised vulnerability to storm events or responses to groundwater ix flow variability. It remains to be determined whether these factors are definitive risks to the sensitive supratidal microbialite systems. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2024
- Full Text:
- Date Issued: 2024-12
Gymnopilus junonius and Rhodofomitopsis lilacinogilva: In vitro evaluation of antimycobacterial activity, safety assessment and isolation of active compounds
- Authors: Didloff, Jenske
- Date: 2024-12
- Subjects: Antibacterial agents , Plants, Useful -- South Africa , Medicinal plants -- South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/68840 , vital:77122
- Description: Tuberculosis remains a significant public health challenge due to the complexity and compliance issues of its treatment, the prevalence of latent infections, the high rate of HIV co-infection, and the spread of drug-resistant strains. This highlights the need to search for new antimycobacterial drugs. Natural products have historically been used as sources for the discovery of pharmaceuticals. Although medicinal macrofungi have been exploited in traditional folk medicines for the treatment of various diseases, research into their antimycobacterial activity remains limited.The aim of this study was to isolate, identify, and characterise the antimycobacterial compound(s) present in ethanol fruiting body extracts of Gymnopilus junonius (Fr.) P.D. Orton (Hymenogastraceae) and Rhodofomitopsis lilacinogilva (Berk.) B.K. Cui, M.L. Han, & Y.C. Dai (Fomitopsidaceae), as well as to investigate their mechanism of action and potential toxicity using in vitro and in vivo screening methods.Bioassay-guided fractionation was conducted using column chromatography and preparative thin-layer chromatography to isolate the active antimycobacterial fraction/compound from ethanol extracts of G. junonius and R. lilacinogilva. Antimycobacterial activity against M. tuberculosis H37Rv was screened using a resazurin microplate assay (REMA). The chemical structure was elucidated employing 1D-(1H NMR) and 2D NMR spectroscopy (HSQC, HMBC) techniques, along with High- Performance Liquid Chromatography High-Resolution Electron Spray Ionisation Mass Spectrometry (HPLC-HRESI-MS). Transmission electron microscopy (TEM) was utilised to observe the ultrastructural changes in M. tuberculosis induced by the active fraction/compound. Toxicity assessment was performed on African green monkeykidney (Vero) and human hepatoma (C3A) cell lines using various staining techniques to observe the potential risk for hepatotoxicity (CellRox orange, TMRE, and MTG staining) and genotoxicity (NucRed staining). In vivo toxicity of extracts was evaluated using a zebrafish embryo/larvae model to observe developmental and teratogenic effects.The bioassay-guided fractionation of G. junonius and R. lilacinogilva extracts yielded an active compound and a fraction displaying inhibitory activity against M. tuberculosis, with MIC values of 31.25 μg/mL and 250 μg/mL, respectively. Gymnopilene was identified as the main active compound isolated from G. junonius, while fraction 8 from R. lilacinogilva contained a predominant constituent resembling a pachymic acid derivative. Transmission electron microscopy revealed ultrastructural damage to M. tuberculosis cells upon treatment with gymnopilene and fraction 8, which was observed as the disruption and disintegration of the cell wall. In vitro toxicity assessment indicated a reduction in the cell density in both Vero and C3A cell lines following exposure to the fractions/gymnopilene. Although there were no significant alterations in the production of reactive oxygen species, changes in mitochondrial dynamics were observed. Genotoxic assessment showed no significant changes. In vivo toxicity assessment showed no significant effects for G. junonius against the zebrafish embryos/larvae, whereas R. lilacinogilva remained toxic and induced developmental abnormalities over a 72-hour time period.The findings of this study highlight the potential of macrofungi as a valuable source of bioactive compounds, confirming the significance of natural products in drug discovery. Notably, this research represents the first to demonstrate that the predominant compound, gymnopilene, isolated from G. junonius exhibits inhibitory activity against M. tuberculosis, contributing to the novelty of the study. Furthermore, the study expands our understanding of the antimycobacterial properties of the selected macrofungal species, G. junonius and R. lilacinogilva, by demonstrating the ultrastructural damage to M. tuberculosis cell wall induced by treatment. However, it is important to recognise the potential toxicity identified through in vitro and/or in vivo screening assays. The observed toxicity may hamper their suitability formdrug development. Future investigations could explore the inclusion of additional in vitro based models, perhaps more complex and physiologically relevant models alongside the in vivo screening model to assess the therapeutic potential of isolated fractions/compounds. , Thesis (PhD) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Didloff, Jenske
- Date: 2024-12
- Subjects: Antibacterial agents , Plants, Useful -- South Africa , Medicinal plants -- South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/68840 , vital:77122
- Description: Tuberculosis remains a significant public health challenge due to the complexity and compliance issues of its treatment, the prevalence of latent infections, the high rate of HIV co-infection, and the spread of drug-resistant strains. This highlights the need to search for new antimycobacterial drugs. Natural products have historically been used as sources for the discovery of pharmaceuticals. Although medicinal macrofungi have been exploited in traditional folk medicines for the treatment of various diseases, research into their antimycobacterial activity remains limited.The aim of this study was to isolate, identify, and characterise the antimycobacterial compound(s) present in ethanol fruiting body extracts of Gymnopilus junonius (Fr.) P.D. Orton (Hymenogastraceae) and Rhodofomitopsis lilacinogilva (Berk.) B.K. Cui, M.L. Han, & Y.C. Dai (Fomitopsidaceae), as well as to investigate their mechanism of action and potential toxicity using in vitro and in vivo screening methods.Bioassay-guided fractionation was conducted using column chromatography and preparative thin-layer chromatography to isolate the active antimycobacterial fraction/compound from ethanol extracts of G. junonius and R. lilacinogilva. Antimycobacterial activity against M. tuberculosis H37Rv was screened using a resazurin microplate assay (REMA). The chemical structure was elucidated employing 1D-(1H NMR) and 2D NMR spectroscopy (HSQC, HMBC) techniques, along with High- Performance Liquid Chromatography High-Resolution Electron Spray Ionisation Mass Spectrometry (HPLC-HRESI-MS). Transmission electron microscopy (TEM) was utilised to observe the ultrastructural changes in M. tuberculosis induced by the active fraction/compound. Toxicity assessment was performed on African green monkeykidney (Vero) and human hepatoma (C3A) cell lines using various staining techniques to observe the potential risk for hepatotoxicity (CellRox orange, TMRE, and MTG staining) and genotoxicity (NucRed staining). In vivo toxicity of extracts was evaluated using a zebrafish embryo/larvae model to observe developmental and teratogenic effects.The bioassay-guided fractionation of G. junonius and R. lilacinogilva extracts yielded an active compound and a fraction displaying inhibitory activity against M. tuberculosis, with MIC values of 31.25 μg/mL and 250 μg/mL, respectively. Gymnopilene was identified as the main active compound isolated from G. junonius, while fraction 8 from R. lilacinogilva contained a predominant constituent resembling a pachymic acid derivative. Transmission electron microscopy revealed ultrastructural damage to M. tuberculosis cells upon treatment with gymnopilene and fraction 8, which was observed as the disruption and disintegration of the cell wall. In vitro toxicity assessment indicated a reduction in the cell density in both Vero and C3A cell lines following exposure to the fractions/gymnopilene. Although there were no significant alterations in the production of reactive oxygen species, changes in mitochondrial dynamics were observed. Genotoxic assessment showed no significant changes. In vivo toxicity assessment showed no significant effects for G. junonius against the zebrafish embryos/larvae, whereas R. lilacinogilva remained toxic and induced developmental abnormalities over a 72-hour time period.The findings of this study highlight the potential of macrofungi as a valuable source of bioactive compounds, confirming the significance of natural products in drug discovery. Notably, this research represents the first to demonstrate that the predominant compound, gymnopilene, isolated from G. junonius exhibits inhibitory activity against M. tuberculosis, contributing to the novelty of the study. Furthermore, the study expands our understanding of the antimycobacterial properties of the selected macrofungal species, G. junonius and R. lilacinogilva, by demonstrating the ultrastructural damage to M. tuberculosis cell wall induced by treatment. However, it is important to recognise the potential toxicity identified through in vitro and/or in vivo screening assays. The observed toxicity may hamper their suitability formdrug development. Future investigations could explore the inclusion of additional in vitro based models, perhaps more complex and physiologically relevant models alongside the in vivo screening model to assess the therapeutic potential of isolated fractions/compounds. , Thesis (PhD) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-12
Impact of an educational intervention on hygiene knowledge and practices among municipal waste and sanitation workers in Nelson Mandela Bay, South Africa
- Authors: Ntunja, Alive
- Date: 2024-12
- Subjects: Public health , Hygiene , Environmental health
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69738 , vital:78015
- Description: Municipal waste and sanitation workers (street sweepers, latrine cleaners, and waste transporters) play a crucial role in maintaining public health by providing a safe and clean environment. They accomplish this by performing tasks such as sweeping streets, collecting domestic waste regularly, pit latrine cleaning, cleaning public toilets, and operating waste collection trucks. Nonetheless, they play an important role in mitigating health-related challenges by ensuring a clean and healthy environment through correct waste collection and disposal practices. Therefore, safe waste collection is a critical undertaking that safeguards the health and living conditions of individuals worldwide. However, their hygiene-related knowledge and practices remain low due to a lack of educational intervention programmes on hygiene. Therefore, the study investigated the impact of an educational intervention on hygiene knowledge and practices amongst municipal waste and sanitation workers in Nelson Mandela Bay Municipality (NMBM). The study used a quasi-experimental study, one group, (pre- and post-test) design, using an educational intervention. A total of 201 municipal waste and sanitation workers were conveniently sampled in the study from all five municipal waste depots and six wastewater treatment plants in the NMBM. A self-administered, structured, hard-copy questionnaire was used to collect the participants’ demographic data and a pre-intervention assessment on hygiene-related knowledge and practices. An educational intervention based on existing literature and national environmental cleaning guidelines and policies was implemented, and after a minimum gap of two months following the intervention, participants were asked to complete the postintervention questionnaire. The collected data was captured in a QuestionPro survey platform and analysed in Microsoft Office 365 (2019 version) and R software (version 4.4.1). The knowledge and practice items were further evaluated for internal reliability using the Cronbach’s alpha technique. Inferential statistics were used to analyse and describe the data, including tests such as Pearson’s correlations, student t-tests, analysis of variance (ANOVA) and multivariable linear regression analysis. A total of 201 participants, comprising 148 (73.6%) males and 53 (26.4%) females, participated in the study. Of the 201 participants, 95 (47.3%) indicated that 2 they had never heard of hygiene-related diseases. The study participants had poor knowledge and practices regarding hygiene prior to the educational intervention. Based on the paired samples t-test, there was a significant difference post-intervention phase in the mean scores for hygiene knowledge of 4.0 (±4.8), p<0.001 as well as hygiene practice scores of 4.3 (±3.4), p<0.001. Output obtained from the multivariable linear regression analysis revealed that participants working in Depot (A) (β=-2.82, p=0.005) were less knowledgeable about hygiene compared to those in Depot (B) in the pre-intervention phase. Participants who have not heard of hygiene-related diseases (β=-3.05, p<0.001) were significantly less knowledgeable about hygiene than their counterparts who have previously heard about hygiene-related diseases. Participants older than 51 years of age had poorer knowledge (b=-0.09, p=0.919) regarding hygiene when compared to the participants who were 18-30 years old. Furthermore, only female participants (b=1.44, p=0.022) and the Coloured ethnic group (b=1.44, p=0.050) had good hygiene practices when handling waste, compared to male participants and those of Black African ethnicity. The study's findings highlight the significant positive impact of an implemented educational intervention programme amongst municipal waste and sanitation workers on improving their knowledge of hygiene-related diseases and hygiene practices when discharging their duties. However, predictor factors such as working environment, educational training background, age, and race significantly influenced the impact of the implemented educational programme. The ongoing implementation of similar initiatives is highly recommended amongst municipal waste and sanitation workers, thus preventing hygiene-related infections amongst the studied population and fostering a healthier environment. , Thesis (MSc) -- Faculty of Science, School of Behavioural & Lifestyle Sciences, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Ntunja, Alive
- Date: 2024-12
- Subjects: Public health , Hygiene , Environmental health
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69738 , vital:78015
- Description: Municipal waste and sanitation workers (street sweepers, latrine cleaners, and waste transporters) play a crucial role in maintaining public health by providing a safe and clean environment. They accomplish this by performing tasks such as sweeping streets, collecting domestic waste regularly, pit latrine cleaning, cleaning public toilets, and operating waste collection trucks. Nonetheless, they play an important role in mitigating health-related challenges by ensuring a clean and healthy environment through correct waste collection and disposal practices. Therefore, safe waste collection is a critical undertaking that safeguards the health and living conditions of individuals worldwide. However, their hygiene-related knowledge and practices remain low due to a lack of educational intervention programmes on hygiene. Therefore, the study investigated the impact of an educational intervention on hygiene knowledge and practices amongst municipal waste and sanitation workers in Nelson Mandela Bay Municipality (NMBM). The study used a quasi-experimental study, one group, (pre- and post-test) design, using an educational intervention. A total of 201 municipal waste and sanitation workers were conveniently sampled in the study from all five municipal waste depots and six wastewater treatment plants in the NMBM. A self-administered, structured, hard-copy questionnaire was used to collect the participants’ demographic data and a pre-intervention assessment on hygiene-related knowledge and practices. An educational intervention based on existing literature and national environmental cleaning guidelines and policies was implemented, and after a minimum gap of two months following the intervention, participants were asked to complete the postintervention questionnaire. The collected data was captured in a QuestionPro survey platform and analysed in Microsoft Office 365 (2019 version) and R software (version 4.4.1). The knowledge and practice items were further evaluated for internal reliability using the Cronbach’s alpha technique. Inferential statistics were used to analyse and describe the data, including tests such as Pearson’s correlations, student t-tests, analysis of variance (ANOVA) and multivariable linear regression analysis. A total of 201 participants, comprising 148 (73.6%) males and 53 (26.4%) females, participated in the study. Of the 201 participants, 95 (47.3%) indicated that 2 they had never heard of hygiene-related diseases. The study participants had poor knowledge and practices regarding hygiene prior to the educational intervention. Based on the paired samples t-test, there was a significant difference post-intervention phase in the mean scores for hygiene knowledge of 4.0 (±4.8), p<0.001 as well as hygiene practice scores of 4.3 (±3.4), p<0.001. Output obtained from the multivariable linear regression analysis revealed that participants working in Depot (A) (β=-2.82, p=0.005) were less knowledgeable about hygiene compared to those in Depot (B) in the pre-intervention phase. Participants who have not heard of hygiene-related diseases (β=-3.05, p<0.001) were significantly less knowledgeable about hygiene than their counterparts who have previously heard about hygiene-related diseases. Participants older than 51 years of age had poorer knowledge (b=-0.09, p=0.919) regarding hygiene when compared to the participants who were 18-30 years old. Furthermore, only female participants (b=1.44, p=0.022) and the Coloured ethnic group (b=1.44, p=0.050) had good hygiene practices when handling waste, compared to male participants and those of Black African ethnicity. The study's findings highlight the significant positive impact of an implemented educational intervention programme amongst municipal waste and sanitation workers on improving their knowledge of hygiene-related diseases and hygiene practices when discharging their duties. However, predictor factors such as working environment, educational training background, age, and race significantly influenced the impact of the implemented educational programme. The ongoing implementation of similar initiatives is highly recommended amongst municipal waste and sanitation workers, thus preventing hygiene-related infections amongst the studied population and fostering a healthier environment. , Thesis (MSc) -- Faculty of Science, School of Behavioural & Lifestyle Sciences, 2024
- Full Text:
- Date Issued: 2024-12
Impact of artificial intelligence and digitalisation on lean manufacturing and its drive for industrial revolution and smart factories
- Authors: Ninan, Abel
- Date: 2024-12
- Subjects: Artificial intelligence , Lean manufacturing -- South Africa , Manufacturing industries -- South Africa -- Automation
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/70001 , vital:78272
- Description: Digitalisation with the development and rising of Artificial Intelligence has hugely transformed the Lean Manufacturing environment and enhanced the transition to Industry 4.0 and Smart factories. Organisations in South Africa are faced with a large variety of issues as they make the shift to Industry 4.0 and Smart Factories, with some problems being based on political will and expertise. This research looks at how developments in Digitalisation and Artificial Intelligence can be integrated and relate with Lean Manufacturing methodologies, which can enhance productivity but at the same time reduce waste, while fostering continuous improvement. The focus is on Lean Manufacturing processes, which can be optimised and enhanced through data analytics, and predictive technologies, through the combination of Artificial Intelligence and emerging technologies in the digital space. The future industrial revolution could be enhanced by development in these areas, which can create and revolutionise production to become more efficient, flexible, and reactive. The research is based on a qualitative approach and involved the analysis of current literature as well as in depth interviews of 15 participants who were chosen based on their work experience and industry, they fall in. This research aims to identify current and possible future relationships between Lean Manufacturing, Digitalisation, Industry 4.0 and SMART factories. The research further attempts to understand how Digitalisation and AI together with emerging technologies can improve and enhance Lean capabilities, operational efficiencies, and contribute to the development and rise of Smart factories. Organisations in South Africa are faced with a large variety of issues as they make the shift to Industry 4.0 and Smart Factories, with some problems being based on political will and expertise. Lean Manufacturing has many benefits in solving these problems because of its emphasis on both process optimisation and waste reduction. Lean Manufacturing improves manufacturing productivity, promotes morale, lowers costs, increases profitability, and optimises space and inventory management by getting rid of non-value-adding operations. These various advantages are further enhanced by the incorporation of digitalisation, which turns manual operations into digital ones and improves data accessibility, cuts waste, and enables real-time monitoring. Large amounts of data are easier to monitor and analyse using digital technologies than they are with old manual approaches. Digitalisation and Lean Manufacturing concepts work together to optimize processes and provide artificial intelligence the ability to use processed data for predictive analytics and self-making. AI helps to create autonomous, self-sufficient Smart Factories by enabling the discovery and removal of non-value-adding operations via its rapid analysis of historical and real-time data. The combination of Industry 4.0, Digitalization, AI, and Lean Manufacturing creates a cooperative and collaborative environment where technology boosts productivity and competitiveness in the manufacturing sector. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Ninan, Abel
- Date: 2024-12
- Subjects: Artificial intelligence , Lean manufacturing -- South Africa , Manufacturing industries -- South Africa -- Automation
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/70001 , vital:78272
- Description: Digitalisation with the development and rising of Artificial Intelligence has hugely transformed the Lean Manufacturing environment and enhanced the transition to Industry 4.0 and Smart factories. Organisations in South Africa are faced with a large variety of issues as they make the shift to Industry 4.0 and Smart Factories, with some problems being based on political will and expertise. This research looks at how developments in Digitalisation and Artificial Intelligence can be integrated and relate with Lean Manufacturing methodologies, which can enhance productivity but at the same time reduce waste, while fostering continuous improvement. The focus is on Lean Manufacturing processes, which can be optimised and enhanced through data analytics, and predictive technologies, through the combination of Artificial Intelligence and emerging technologies in the digital space. The future industrial revolution could be enhanced by development in these areas, which can create and revolutionise production to become more efficient, flexible, and reactive. The research is based on a qualitative approach and involved the analysis of current literature as well as in depth interviews of 15 participants who were chosen based on their work experience and industry, they fall in. This research aims to identify current and possible future relationships between Lean Manufacturing, Digitalisation, Industry 4.0 and SMART factories. The research further attempts to understand how Digitalisation and AI together with emerging technologies can improve and enhance Lean capabilities, operational efficiencies, and contribute to the development and rise of Smart factories. Organisations in South Africa are faced with a large variety of issues as they make the shift to Industry 4.0 and Smart Factories, with some problems being based on political will and expertise. Lean Manufacturing has many benefits in solving these problems because of its emphasis on both process optimisation and waste reduction. Lean Manufacturing improves manufacturing productivity, promotes morale, lowers costs, increases profitability, and optimises space and inventory management by getting rid of non-value-adding operations. These various advantages are further enhanced by the incorporation of digitalisation, which turns manual operations into digital ones and improves data accessibility, cuts waste, and enables real-time monitoring. Large amounts of data are easier to monitor and analyse using digital technologies than they are with old manual approaches. Digitalisation and Lean Manufacturing concepts work together to optimize processes and provide artificial intelligence the ability to use processed data for predictive analytics and self-making. AI helps to create autonomous, self-sufficient Smart Factories by enabling the discovery and removal of non-value-adding operations via its rapid analysis of historical and real-time data. The combination of Industry 4.0, Digitalization, AI, and Lean Manufacturing creates a cooperative and collaborative environment where technology boosts productivity and competitiveness in the manufacturing sector. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
Investigate how ethical organisational behaviour in service delivery at the Gqeberha labour centre can be improved
- Authors: Khahlana, Lwazi
- Date: 2024-12
- Subjects: Corporate culture , Business ethics , Psychology, Industrial
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/70231 , vital:78331
- Description: The public service is often perceived and experienced as not meeting the expectations of the public. The Gqeberha Labour Centre (GQE LC) is not exempted to prevalence of unethical work behaviours in service delivery. The GQE LC is the Department of Employment and Labour (DEL) branch. The purpose of the study is to investigate how ethical organisational behaviour in service delivery at GQE LC can be improved. The study applied qualitative approach through an interpretivism paradigm. The study used purposive sampling strategy. The sample size had ten participants, seven professionals and three management. The data was collected making use of semi-structured interviews that were done one-on-one. A Computer-Assisted Qualitative Data Analysis Software was used to transcribe the data. The data analysis was done manually using thematic analysis. The findings on leadership role in the improvement of ethical organisational behaviour, indicated training is one of the key roles to be implemented by leadership; leadership should be exemplary on ethical organisational behaviour; new employees should be onboarded on ethical organisational behaviour as soon as they are employed. The finding improvement and mitigation of causes and negative outcomes of unethical behaviour, indicated whistleblowing should be encouraged; unethical behaviour be sanctioned and continuous training on ethical organisational behaviour. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Khahlana, Lwazi
- Date: 2024-12
- Subjects: Corporate culture , Business ethics , Psychology, Industrial
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/70231 , vital:78331
- Description: The public service is often perceived and experienced as not meeting the expectations of the public. The Gqeberha Labour Centre (GQE LC) is not exempted to prevalence of unethical work behaviours in service delivery. The GQE LC is the Department of Employment and Labour (DEL) branch. The purpose of the study is to investigate how ethical organisational behaviour in service delivery at GQE LC can be improved. The study applied qualitative approach through an interpretivism paradigm. The study used purposive sampling strategy. The sample size had ten participants, seven professionals and three management. The data was collected making use of semi-structured interviews that were done one-on-one. A Computer-Assisted Qualitative Data Analysis Software was used to transcribe the data. The data analysis was done manually using thematic analysis. The findings on leadership role in the improvement of ethical organisational behaviour, indicated training is one of the key roles to be implemented by leadership; leadership should be exemplary on ethical organisational behaviour; new employees should be onboarded on ethical organisational behaviour as soon as they are employed. The finding improvement and mitigation of causes and negative outcomes of unethical behaviour, indicated whistleblowing should be encouraged; unethical behaviour be sanctioned and continuous training on ethical organisational behaviour. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
Investigating the implementation of teaching strategies used by foundation phase teachers in multilingual classrooms
- Authors: Green, Marizanne
- Date: 2024-12
- Subjects: Multiculturalism -- Study and teaching , Language and languages -- Study and teaching , Education, Bilingual -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/68322 , vital:76974
- Description: In South Africa, there are eleven official languages: English and Afrikaans and nine indigenous languages. However, the dominant language of learning and teaching in multilingual classrooms is English. Teachers are not all equipped to cater for a multilingual classroom that is conducive to learning. Hence, it is important that teaching strategies teachers used need to support learners’ access to knowledge and their language proficiency through the learning process. This qualitative case study aimed at investigating the teaching strategies used by Foundation Phase teachers in multilingual classrooms. The study was guided by an interpretivist paradigm which was helpful in providing in-depth knowledge on multilingual Foundation Phase classrooms and the teaching strategies that teachers implement. The study used a purposive sampling strategy with 4 Foundation phase teachers teaching Grades R-4. Drawing upon classroom observations and semi-structured individual interviews as the primary methods of data collection, the study explored the teaching strategies teachers use in multilingual foundation phase classrooms. A thematic data analysis was employed. Findings revealed a need for inclusive practices in FP multilingual classrooms, need to support learning using various teaching strategies, need to recognize realities in multilingual classrooms and a role that stakeholders can play in learning. Recommendations are provided for SGB’s, Curriculum designers, FP teachers and parents. , Thesis (MEd) -- Faculty of Education, School of Primary School Education, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Green, Marizanne
- Date: 2024-12
- Subjects: Multiculturalism -- Study and teaching , Language and languages -- Study and teaching , Education, Bilingual -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/68322 , vital:76974
- Description: In South Africa, there are eleven official languages: English and Afrikaans and nine indigenous languages. However, the dominant language of learning and teaching in multilingual classrooms is English. Teachers are not all equipped to cater for a multilingual classroom that is conducive to learning. Hence, it is important that teaching strategies teachers used need to support learners’ access to knowledge and their language proficiency through the learning process. This qualitative case study aimed at investigating the teaching strategies used by Foundation Phase teachers in multilingual classrooms. The study was guided by an interpretivist paradigm which was helpful in providing in-depth knowledge on multilingual Foundation Phase classrooms and the teaching strategies that teachers implement. The study used a purposive sampling strategy with 4 Foundation phase teachers teaching Grades R-4. Drawing upon classroom observations and semi-structured individual interviews as the primary methods of data collection, the study explored the teaching strategies teachers use in multilingual foundation phase classrooms. A thematic data analysis was employed. Findings revealed a need for inclusive practices in FP multilingual classrooms, need to support learning using various teaching strategies, need to recognize realities in multilingual classrooms and a role that stakeholders can play in learning. Recommendations are provided for SGB’s, Curriculum designers, FP teachers and parents. , Thesis (MEd) -- Faculty of Education, School of Primary School Education, 2024
- Full Text:
- Date Issued: 2024-12
Investigating the purported medicinal properties of cannabinoid containing products available for human consumption in South Africa
- Authors: Stark, Nicole Jade
- Date: 2024-12
- Subjects: Thin layer chromatography , Tetrahydrocannabinol , Cannabinoids
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69716 , vital:78013
- Description: Cannabis has until recently, in some countries, been classified as an illicit, illegal drug. In South Africa, the sale of marijuana (Cannabis sativa) is still illegal, but there has been an amendment of legislation in the governing of the use of marijuana in that the private use of marijuana was decriminalised in September 2018. This has led to questions about whether the recreational use of Cannabis should be legalised and what is the potential social implications of this legislation moving forward (Mokwena, 2019). This study aimed to assess whether the indications and consequently the concentrations associated with the declared purported use of cannabinoid containing products correspond with the information declared on the label and conform to the regulatory limits set out for these products. The objectives of this study were to explore: the range of products available in South Africa, the prescribed use and dosage of the product and to test the accuracy of the reported information on the product labelling regarding the cannabinoid content. This investigation pursued a quantitative approach that is empirical and comprised of laboratory-based experiments. A minimum of seven samples of different liquid preparations of products, reported to contain cannabinoids and being sold without the need for a prescription or licence were tested with the aid of Thin Layer Chromatography (TLC), to separate individual compounds from the many that could be found in these Cannabis products. The results of this testing of cannabidiol (CBD) and tetrahydrocannabinol (THC) and, where applicable, their concentrations were determined. Using the data collected and review of available literature, assessments were made as to whether the products tested conform to the regulatory standards and contained the cannabinoids as stated on the labelling. From the data obtained findings were that not all products currently available on the South African market correspond to the information reported on the label or conform to the regulatory standards. , Thesis (MPharm) -- Faculty of Health Sciences, School of Clinical Care & Medicinal Sciences, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Stark, Nicole Jade
- Date: 2024-12
- Subjects: Thin layer chromatography , Tetrahydrocannabinol , Cannabinoids
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69716 , vital:78013
- Description: Cannabis has until recently, in some countries, been classified as an illicit, illegal drug. In South Africa, the sale of marijuana (Cannabis sativa) is still illegal, but there has been an amendment of legislation in the governing of the use of marijuana in that the private use of marijuana was decriminalised in September 2018. This has led to questions about whether the recreational use of Cannabis should be legalised and what is the potential social implications of this legislation moving forward (Mokwena, 2019). This study aimed to assess whether the indications and consequently the concentrations associated with the declared purported use of cannabinoid containing products correspond with the information declared on the label and conform to the regulatory limits set out for these products. The objectives of this study were to explore: the range of products available in South Africa, the prescribed use and dosage of the product and to test the accuracy of the reported information on the product labelling regarding the cannabinoid content. This investigation pursued a quantitative approach that is empirical and comprised of laboratory-based experiments. A minimum of seven samples of different liquid preparations of products, reported to contain cannabinoids and being sold without the need for a prescription or licence were tested with the aid of Thin Layer Chromatography (TLC), to separate individual compounds from the many that could be found in these Cannabis products. The results of this testing of cannabidiol (CBD) and tetrahydrocannabinol (THC) and, where applicable, their concentrations were determined. Using the data collected and review of available literature, assessments were made as to whether the products tested conform to the regulatory standards and contained the cannabinoids as stated on the labelling. From the data obtained findings were that not all products currently available on the South African market correspond to the information reported on the label or conform to the regulatory standards. , Thesis (MPharm) -- Faculty of Health Sciences, School of Clinical Care & Medicinal Sciences, 2024
- Full Text:
- Date Issued: 2024-12
Investigation of potential in-situ polymerization reactions for use in lithium-ion batteries
- Authors: Dube, Tafara
- Date: 2024-12
- Subjects: Lithium ion batteries , Lithium cells , Electrochemistry
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/68851 , vital:77127
- Description: With the rise in popularity of electric vehicles and portable electronic devices, having a reliable, lightweight, and long-lasting battery is crucial. This has led to the mass commercialisation of lithium-ion batteries (LIB’s) because they offer several advantages over other battery technologies. Over the years, one of the concerns was with the ease with which the batteries can burn or explode when subjected to certain extreme conditions. In order to build trust in these products and to expand the technology into more diverse applications, safety aspects of the batteries has become of widespread concern resulting in a key area of research. One aspect of improving the safety is by reducing the flammability of the battery by the addition of certain chemicals that stop or suppress the thermal runaway effect. However, this in-turn reduces the battery’s capacity and life-cycle performance. Researchers have used the idea of encapsulating these chemicals thereby physically separating them within the lithium-ion battery (LIB) electrolyte system with a minimum effect on performance. This research aims to explore use of R-diols and R-amines as additives that upon a thermal trigger would react with the lithium-ion battery electrolyte to stop the effect of the thermal runaway by forming carbamate derivatives which are gel-like or form solid aggregates. The R-diols or R-amines can react with electrolyte at higher temperatures with the lithium-hexafluorophosphate acting as a catalyst. This change in the physical state of the electrolyte increases the resistance inside the battery which then hinders ion movement and forms a physical barrier to reduce the effect of short circuiting when the separator or other components are damaged due to higher temperatures. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Dube, Tafara
- Date: 2024-12
- Subjects: Lithium ion batteries , Lithium cells , Electrochemistry
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/68851 , vital:77127
- Description: With the rise in popularity of electric vehicles and portable electronic devices, having a reliable, lightweight, and long-lasting battery is crucial. This has led to the mass commercialisation of lithium-ion batteries (LIB’s) because they offer several advantages over other battery technologies. Over the years, one of the concerns was with the ease with which the batteries can burn or explode when subjected to certain extreme conditions. In order to build trust in these products and to expand the technology into more diverse applications, safety aspects of the batteries has become of widespread concern resulting in a key area of research. One aspect of improving the safety is by reducing the flammability of the battery by the addition of certain chemicals that stop or suppress the thermal runaway effect. However, this in-turn reduces the battery’s capacity and life-cycle performance. Researchers have used the idea of encapsulating these chemicals thereby physically separating them within the lithium-ion battery (LIB) electrolyte system with a minimum effect on performance. This research aims to explore use of R-diols and R-amines as additives that upon a thermal trigger would react with the lithium-ion battery electrolyte to stop the effect of the thermal runaway by forming carbamate derivatives which are gel-like or form solid aggregates. The R-diols or R-amines can react with electrolyte at higher temperatures with the lithium-hexafluorophosphate acting as a catalyst. This change in the physical state of the electrolyte increases the resistance inside the battery which then hinders ion movement and forms a physical barrier to reduce the effect of short circuiting when the separator or other components are damaged due to higher temperatures. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-12
ISO 9001 certification as a catalyst for enhancing product quality at a manufacturing plant in Gqeberha
- Authors: Runesu, Mashoko
- Date: 2024-12
- Subjects: ISO 9001 Standard , Quality control -- Standards , Quality of products
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69925 , vital:78243
- Description: This research explores the role of ISO 9001 certification as a catalyst for enhancing product quality at a manufacturing plant in Gqeberha. ISO 9001, an internationally recognised standard for quality management systems, provides a framework for consistent product quality and continuous improvement. While prior studies have shown that ISO 9001 certification creates a signalling effect, attracting customers by projecting an image of high product quality, the impact of this certification on actual product quality remains unclear. This study addresses this gap by investigating the variables necessary to enhance product quality through ISO 9001 implementation in a manufacturing context. The research seeks to answer the question: What variables should be incorporated in the implementation of ISO 9001 certification to improve product quality in a manufacturing company in Gqeberha? Specifically, the study focuses on the influence of four ISO 9001 principles, namely customer focus, leadership, engagement of people, and improvement, on product quality. A pragmatic research philosophy was adopted, utilising a quantitative approach to better understand the relationship between these principles and product quality. Both literature review and empirical results confirm that all four principles significantly impact product quality with a unit change in any of these principles or variables resulting in a 0,550-to-0,721-unit changes in product quality. Based on these results, the study recommends that companies accredited to ISO 9001 standard should integrate these principles into their daily operations. If the ISO 9001 standard is implemented with emphasis on following these guiding principles, a company will not only achieve and sustain improvements in product quality, but this can be a valuable strategic tool for competitiveness in the global marketplace. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Runesu, Mashoko
- Date: 2024-12
- Subjects: ISO 9001 Standard , Quality control -- Standards , Quality of products
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/69925 , vital:78243
- Description: This research explores the role of ISO 9001 certification as a catalyst for enhancing product quality at a manufacturing plant in Gqeberha. ISO 9001, an internationally recognised standard for quality management systems, provides a framework for consistent product quality and continuous improvement. While prior studies have shown that ISO 9001 certification creates a signalling effect, attracting customers by projecting an image of high product quality, the impact of this certification on actual product quality remains unclear. This study addresses this gap by investigating the variables necessary to enhance product quality through ISO 9001 implementation in a manufacturing context. The research seeks to answer the question: What variables should be incorporated in the implementation of ISO 9001 certification to improve product quality in a manufacturing company in Gqeberha? Specifically, the study focuses on the influence of four ISO 9001 principles, namely customer focus, leadership, engagement of people, and improvement, on product quality. A pragmatic research philosophy was adopted, utilising a quantitative approach to better understand the relationship between these principles and product quality. Both literature review and empirical results confirm that all four principles significantly impact product quality with a unit change in any of these principles or variables resulting in a 0,550-to-0,721-unit changes in product quality. Based on these results, the study recommends that companies accredited to ISO 9001 standard should integrate these principles into their daily operations. If the ISO 9001 standard is implemented with emphasis on following these guiding principles, a company will not only achieve and sustain improvements in product quality, but this can be a valuable strategic tool for competitiveness in the global marketplace. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-12
Low-income area electrification systems
- Authors: Tshabeni, Thulisa
- Date: 2024-12
- Subjects: Rural electrification -- Economic aspects -- South Africa , Rural electrification -- South Africa , Remote area power supply systems -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/68807 , vital:77115
- Description: This research investigated electrification systems for low-income, informal settlement areas via grid extension, photovoltaic mini-grids and solar home system (SHS). Six electrification systems were analysed; four mini-grid systems, a 100 W solar home system and a grid extension. All have different maximum power capacities and differ in the way they contribute to sustainable development. Affordability for the consumer of the total energy required (electrical and other sources) is a key factor for the sustainability of any electrification system. Two battery technologies, lithium-ion and lead acid batteries were compared for each system based on technical and economic performance. The study determined that despite the intial very high cost, lithium-ion batteries can achieve a lower levelized cost of electricity (LCOE) due to their long life span. It was found that the batteries cost between 58% and 95% of the project’s capital cost. The battery cost occurs not only in the capital cost, but in the replacement cost. This cost is so high, that it makes all the solar systems uneconomic. This research found that extending the national power grid is still much more economically viable than all other PV electrification systems, but it requires land tenure. The issue of land tenure could be solved by making some agreement with the land owner for rental. It was found that the PV systems could only be economic if they increased the income of the communities substantially. , Thesis (MEg) -- Faculty of Engineering, the Built Environment, and Technology, School of Engineering, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Tshabeni, Thulisa
- Date: 2024-12
- Subjects: Rural electrification -- Economic aspects -- South Africa , Rural electrification -- South Africa , Remote area power supply systems -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/68807 , vital:77115
- Description: This research investigated electrification systems for low-income, informal settlement areas via grid extension, photovoltaic mini-grids and solar home system (SHS). Six electrification systems were analysed; four mini-grid systems, a 100 W solar home system and a grid extension. All have different maximum power capacities and differ in the way they contribute to sustainable development. Affordability for the consumer of the total energy required (electrical and other sources) is a key factor for the sustainability of any electrification system. Two battery technologies, lithium-ion and lead acid batteries were compared for each system based on technical and economic performance. The study determined that despite the intial very high cost, lithium-ion batteries can achieve a lower levelized cost of electricity (LCOE) due to their long life span. It was found that the batteries cost between 58% and 95% of the project’s capital cost. The battery cost occurs not only in the capital cost, but in the replacement cost. This cost is so high, that it makes all the solar systems uneconomic. This research found that extending the national power grid is still much more economically viable than all other PV electrification systems, but it requires land tenure. The issue of land tenure could be solved by making some agreement with the land owner for rental. It was found that the PV systems could only be economic if they increased the income of the communities substantially. , Thesis (MEg) -- Faculty of Engineering, the Built Environment, and Technology, School of Engineering, 2024
- Full Text:
- Date Issued: 2024-12
Portfolio effect and bet-hedging adaptations in sea turtles
- Authors: Hoekstra, Shaun
- Date: 2024-12
- Subjects: Wildlife conservation , Sea turtles -- South Africa , Animal behavior
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/68873 , vital:77153
- Description: A great proportion of marine species are at risk of going extinct as a result of profound changes in the world’s oceans, primarily driven by human activities. Sea turtles are not exempt from this fate. Despite sea turtles being exposed to a range of environmental conditions and threats that vary in frequency and intensity, these ancient marine reptiles have persisted for millennia. In the past, sea turtles have been able to adapt to natural perturbations while other animal groups have not. The ability of sea turtles to adapt to contemporary changes in conditions, produced by human activities, has become limited. The persistence of sea turtles may be explained by the application of a concept termed “portfolio effect”. An aggregate system is more stable and less prone to fluctuations over time (i.e. portfolio effect) if a diversity of finer components comprises the entire system and displays asynchronous fluctuations over time. Biological entities (e.g. species measured by the abundance trend) may achieve long-term stability even though the individual components (e.g. populations measured in abundance trend) display weak or negative correlations with each other in space and time. Different sea turtle populations may display independent trends in abundances over time, resulting in a portfolio effect at species levels. Trends in sea turtle abundances may be affected by individual behaviour. The adoption of bet-hedging adaptations may enable populations to thrive despite environmental changes or stochasticity, by lowering short-term fitness in exchange for maximising long-term fitness. Individual sea turtles may exhibit bet-hedging adaptations through changes in their temporal nesting behaviour, including the remigration interval. Since remigration interval length regulates the number of nesting females per nesting season, changes in remigration interval will affect abundance trends. The ability of individuals to change their remigration interval allows them to “skip” the breeding migration when environmental conditions seem unfavourable. The overall aim of this thesis was to investigate potential reasons for observed sea turtle abundance trends at species, population, and rookery levels. I tested whether the portfolio effect applies to sea turtles by analysing and interpreting spatiotemporal trends in loggerhead (Caretta caretta) and leatherback (Dermochelys coriacea) abundances at the population and species levels using global datasets. The application of bet-hedging strategies was tested at a local level using data from the long-term monitoring program for South African nesting sea turtles. The majority of loggerhead rookeries displayed an increase in abundance over time, while most leatherback rookeries declined (Chapter 2). Population growth rates also differed among rookeries within Regional Management Units (RMUs) (Chapter 2). This diversity in abundance trends among rookeries suggested spatiotemporal variation in environmental conditions, threats and/or level of protection accompanying sea turtles. The species-level growth rate for both species displayed an overall increase in abundance over time. However, larger (more turtles) leatherback rookeries/RMUs experienced more rapid declines in abundance compared to smaller rookeries/RMUs, resulting in a recent species-level decline. Uncorrelated trends in abundances at the RMU-level could have stabilised species-level trends. Differences in the remigration intervals as a possible bet-hedging adaptation could potentially explain differences in population recovery rates between South Africa’s loggerhead and leatherback sea turtles (Chapter 3), but found no evidence that individuals from either species exhibit bet-hedging adaptations. Loggerheads, however, have increased their remigration intervals over time, while leatherbacks have not. These increases were accompanied by declines in adult body size (previously established) which could be an effect of diminishing foraging area quality. The increased remigration interval shown by loggerheads may be a response rather than an adaptation to the prevailing environmental conditions that impact their food supply in their foraging areas. The population growth rate of leatherback sea turtles may surpass that of the loggerheads in the near future, although there is a global decline in abundance (Chapter 2). This dissertation provides information on possible reasons for observed trends in sea turtle abundances at various levels of biological organisation. While a variety of factors have the potential to influence trends in sea turtle abundance, the possible occurrence of portfolio effects and investigating nesting behaviour may resolve any uncertainties regarding the reasons for observed trends in abundance. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2024
- Full Text:
- Date Issued: 2024-12
- Authors: Hoekstra, Shaun
- Date: 2024-12
- Subjects: Wildlife conservation , Sea turtles -- South Africa , Animal behavior
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/68873 , vital:77153
- Description: A great proportion of marine species are at risk of going extinct as a result of profound changes in the world’s oceans, primarily driven by human activities. Sea turtles are not exempt from this fate. Despite sea turtles being exposed to a range of environmental conditions and threats that vary in frequency and intensity, these ancient marine reptiles have persisted for millennia. In the past, sea turtles have been able to adapt to natural perturbations while other animal groups have not. The ability of sea turtles to adapt to contemporary changes in conditions, produced by human activities, has become limited. The persistence of sea turtles may be explained by the application of a concept termed “portfolio effect”. An aggregate system is more stable and less prone to fluctuations over time (i.e. portfolio effect) if a diversity of finer components comprises the entire system and displays asynchronous fluctuations over time. Biological entities (e.g. species measured by the abundance trend) may achieve long-term stability even though the individual components (e.g. populations measured in abundance trend) display weak or negative correlations with each other in space and time. Different sea turtle populations may display independent trends in abundances over time, resulting in a portfolio effect at species levels. Trends in sea turtle abundances may be affected by individual behaviour. The adoption of bet-hedging adaptations may enable populations to thrive despite environmental changes or stochasticity, by lowering short-term fitness in exchange for maximising long-term fitness. Individual sea turtles may exhibit bet-hedging adaptations through changes in their temporal nesting behaviour, including the remigration interval. Since remigration interval length regulates the number of nesting females per nesting season, changes in remigration interval will affect abundance trends. The ability of individuals to change their remigration interval allows them to “skip” the breeding migration when environmental conditions seem unfavourable. The overall aim of this thesis was to investigate potential reasons for observed sea turtle abundance trends at species, population, and rookery levels. I tested whether the portfolio effect applies to sea turtles by analysing and interpreting spatiotemporal trends in loggerhead (Caretta caretta) and leatherback (Dermochelys coriacea) abundances at the population and species levels using global datasets. The application of bet-hedging strategies was tested at a local level using data from the long-term monitoring program for South African nesting sea turtles. The majority of loggerhead rookeries displayed an increase in abundance over time, while most leatherback rookeries declined (Chapter 2). Population growth rates also differed among rookeries within Regional Management Units (RMUs) (Chapter 2). This diversity in abundance trends among rookeries suggested spatiotemporal variation in environmental conditions, threats and/or level of protection accompanying sea turtles. The species-level growth rate for both species displayed an overall increase in abundance over time. However, larger (more turtles) leatherback rookeries/RMUs experienced more rapid declines in abundance compared to smaller rookeries/RMUs, resulting in a recent species-level decline. Uncorrelated trends in abundances at the RMU-level could have stabilised species-level trends. Differences in the remigration intervals as a possible bet-hedging adaptation could potentially explain differences in population recovery rates between South Africa’s loggerhead and leatherback sea turtles (Chapter 3), but found no evidence that individuals from either species exhibit bet-hedging adaptations. Loggerheads, however, have increased their remigration intervals over time, while leatherbacks have not. These increases were accompanied by declines in adult body size (previously established) which could be an effect of diminishing foraging area quality. The increased remigration interval shown by loggerheads may be a response rather than an adaptation to the prevailing environmental conditions that impact their food supply in their foraging areas. The population growth rate of leatherback sea turtles may surpass that of the loggerheads in the near future, although there is a global decline in abundance (Chapter 2). This dissertation provides information on possible reasons for observed trends in sea turtle abundances at various levels of biological organisation. While a variety of factors have the potential to influence trends in sea turtle abundance, the possible occurrence of portfolio effects and investigating nesting behaviour may resolve any uncertainties regarding the reasons for observed trends in abundance. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2024
- Full Text:
- Date Issued: 2024-12