Factors constraining and enabling the adoption of a disruptive technology by African small, micro, and medium enterprises for the Fourth Industrial Revolution: The case of mobile money
- Authors: Tarr, Dillon
- Date: 2022-10-14
- Subjects: Disruptive technologies , Mobile commerce , Industry 4.0 , Small business Africa, Sub-Saharan , Diffusion of innovations Africa, Sub-Saharan , Technological innovations Management
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/357709 , vital:64770
- Description: The Fourth Industrial Revolution (4IR) is set to disrupt existing economic and social structures through the use of cyber-physical systems that result from a fusion of the digital, biological, and physical spheres. The fifth and current long wave of innovation is going through such a digital revolution in the ongoing deployment period which is being driven by the generalpurpose technologies of Artificial Intelligence and the Internet of Things, among other cyberphysical systems. The impact of mobile money in the access of financial services has shown how disruptive incremental innovations in mobile and digital technologies can be. The transformational power of mobile money in financial access is due to its use as an accessible financial tool that utilizes mobile devices to send and/or receive money over great distances. With the 4IR looming, this thesis determines the factors that enable and constrain the adoption of a disruptive technology amongst Sub-Saharan African small, micro, and medium enterprises (SMMEs). Therefore, due to its impact on financial inclusion and the formalization of SMMEs, mobile money is used as an indicator for the adoption of 4IR disruptive digital technologies. The adoption of mobile money was evaluated using secondary data from a survey conducted by Research ICT Africa, which surveyed 4408 SMMEs in nine African countries. The Diffusion of Innovations (DOI) model and the Unified Theory of Acceptance and Use of Technology (UTAUT) model were used to identify the factors enabling and constraining the adoption of a disruptive technology, in this case mobile money. Factors included gender, vocational training, business skills training, tertiary education, services, performance expectancy, social media, location, and nine African countries (Kenya, Mozambique, Ghana, Nigeria, Rwanda, South Africa, Tanzania, Uganda, and Senegal). The factors were grouped into owner characteristics, firm attributes and country attributes. SMME owners with business skills (49%) showed the highest level of adoption in terms of owner characteristics, Kenyan SMMEs (21%) had the highest adoption between the countries surveyed, and social media (62%) showed the highest adoption in terms of firm attributes followed by the formal variable (47%). In general, only 29% of SMMEs surveyed adopted mobile money. The study found that women SMME owners were more likely to be affected by business formality when adopting a disruptive technology compared to male owned SMMEs. This is because informality often exacerbates other barriers/challenges women face such as lower access to finance, lower ability to exercise property, business, and labour rights, and lower visibility. The results also demonstrate that vocational training is more important than general tertiary education for the ii adoption of a disruptive technology such as mobile money. Furthermore, when using social media as a tool for business advice SMME owners were more likely to adopt the disruptive technology. The study suggests that to encourage African SMMEs to adequately adopt disruptive technologies of the 4IR, more women owned SMMEs need to enter the formal economy, and vocational training targeted at business skills must be promoted amongst all SMME owners. Eastern African SMMEs were found to be more likely to adopt mobile money compared to other African regions. The finding demonstrates the need for more African countries (particularly outside of the Eastern African region) to encourage innovation by addressing the four enablers of mobile connectivity (i.e. infrastructure, affordability, consumer readiness, and mobile services) which will in effect lead to economic growth and development. The study shows that to address country/regional differences, in addition to building the required infrastructure in terms of mobile internet connectivity, countries should increase the local relevancy of disruptive technologies between SMMEs. To achieve this the study suggests increasing mobile social media penetration rates. This is because when social media is used as a tool for business advice SMME owners are more likely to adopt a disruptive technology (as is the case with mobile money) due to the social influence of social media. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Tarr, Dillon
- Date: 2022-10-14
- Subjects: Disruptive technologies , Mobile commerce , Industry 4.0 , Small business Africa, Sub-Saharan , Diffusion of innovations Africa, Sub-Saharan , Technological innovations Management
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/357709 , vital:64770
- Description: The Fourth Industrial Revolution (4IR) is set to disrupt existing economic and social structures through the use of cyber-physical systems that result from a fusion of the digital, biological, and physical spheres. The fifth and current long wave of innovation is going through such a digital revolution in the ongoing deployment period which is being driven by the generalpurpose technologies of Artificial Intelligence and the Internet of Things, among other cyberphysical systems. The impact of mobile money in the access of financial services has shown how disruptive incremental innovations in mobile and digital technologies can be. The transformational power of mobile money in financial access is due to its use as an accessible financial tool that utilizes mobile devices to send and/or receive money over great distances. With the 4IR looming, this thesis determines the factors that enable and constrain the adoption of a disruptive technology amongst Sub-Saharan African small, micro, and medium enterprises (SMMEs). Therefore, due to its impact on financial inclusion and the formalization of SMMEs, mobile money is used as an indicator for the adoption of 4IR disruptive digital technologies. The adoption of mobile money was evaluated using secondary data from a survey conducted by Research ICT Africa, which surveyed 4408 SMMEs in nine African countries. The Diffusion of Innovations (DOI) model and the Unified Theory of Acceptance and Use of Technology (UTAUT) model were used to identify the factors enabling and constraining the adoption of a disruptive technology, in this case mobile money. Factors included gender, vocational training, business skills training, tertiary education, services, performance expectancy, social media, location, and nine African countries (Kenya, Mozambique, Ghana, Nigeria, Rwanda, South Africa, Tanzania, Uganda, and Senegal). The factors were grouped into owner characteristics, firm attributes and country attributes. SMME owners with business skills (49%) showed the highest level of adoption in terms of owner characteristics, Kenyan SMMEs (21%) had the highest adoption between the countries surveyed, and social media (62%) showed the highest adoption in terms of firm attributes followed by the formal variable (47%). In general, only 29% of SMMEs surveyed adopted mobile money. The study found that women SMME owners were more likely to be affected by business formality when adopting a disruptive technology compared to male owned SMMEs. This is because informality often exacerbates other barriers/challenges women face such as lower access to finance, lower ability to exercise property, business, and labour rights, and lower visibility. The results also demonstrate that vocational training is more important than general tertiary education for the ii adoption of a disruptive technology such as mobile money. Furthermore, when using social media as a tool for business advice SMME owners were more likely to adopt the disruptive technology. The study suggests that to encourage African SMMEs to adequately adopt disruptive technologies of the 4IR, more women owned SMMEs need to enter the formal economy, and vocational training targeted at business skills must be promoted amongst all SMME owners. Eastern African SMMEs were found to be more likely to adopt mobile money compared to other African regions. The finding demonstrates the need for more African countries (particularly outside of the Eastern African region) to encourage innovation by addressing the four enablers of mobile connectivity (i.e. infrastructure, affordability, consumer readiness, and mobile services) which will in effect lead to economic growth and development. The study shows that to address country/regional differences, in addition to building the required infrastructure in terms of mobile internet connectivity, countries should increase the local relevancy of disruptive technologies between SMMEs. To achieve this the study suggests increasing mobile social media penetration rates. This is because when social media is used as a tool for business advice SMME owners are more likely to adopt a disruptive technology (as is the case with mobile money) due to the social influence of social media. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2022
- Full Text:
- Date Issued: 2022-10-14
Social upgrading or dependency?: Investigating the implications of the inclusion of commercial wine farms within South African Fairtrade certification
- Authors: Bell, Joshua
- Date: 2022-10-14
- Subjects: Competition, Unfair South Africa , Wine industry South Africa Employees , Unfair labor practices South Africa , Fairtrade International , International trade , Economic development Moral and ethical aspects South Africa , Wine industry Moral and ethical aspects South Africa , Work environment South Africa
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/327155 , vital:61086 , DOI 10.21504/10962/327155
- Description: The South African wine industry is one of the oldest sectors of the country’s economy, beginning in the early years of South African colonialism in the 17th century through the use of slave and slave-like labour. As an industry that has been defined by farm paternalism and dependency, the South African wine industry has had to demonstrate changes from its history of extreme racial and gendered exploitation to an industry that reflects the democratic values of a new South Africa. Ethical certifications are considered one way through which the post-apartheid South African wine industry can demonstrate that it has moved away from its historical practices and is now characterised by practices of decent work and social transformation. An important certificatory label that allows local wine producers entry into global wine production networks is Fairtrade International. While Fairtrade certification is often reserved for small-scale producers, this certification has been extended to large-scale, commercial producers within the South African wine industry despite its history of farm paternalism and dependency. This research asks if this inclusion promotes decent work through social upgrading or if it offers a platform for the continuation of farm dependency under the guise of ‘Fairtrade’. In this study, social upgrading has been defined through a ‘bottom-up’ approach that prioritises workers’ independence as a key means of improvement. Four key pillars are applied as embodying the concept of social upgrading: regular employment with set working hours; legally enforceable worker rights; social protection through collective and individual bargaining power; and non-discriminatory social dialogue that promotes significant socio-economic progression. A key finding of this research is that practices of dependency and paternalism continue on some large-scale commercial farms, despite their Fairtrade certification. Furthermore, the findings suggest that the benefits that farmworkers receive lock farmworkers into their position on the farm with marginally improved conditions and cease if workers depart from the Fairtrade wine farm. This suggests that, at best, this inclusion of commercial farmers within Fairtrade certification appears to create a top-down form of social upgrading that locks farmworkers into their position on the farm with marginally improved conditions and beneath a glass ceiling of development. At worst, this Fairtrade inclusion facilitates a global poverty network through paternalism and dependency under the guise of ‘Fairtrade’. As a result, where meaningful, bottom-up social upgrading may occur on South African wine farms, the study suggests that this is despite the presence of Fairtrade and not a result of it. , Thesis (PhD) -- Faculty of Humanities, Political and Interntional Studies, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Bell, Joshua
- Date: 2022-10-14
- Subjects: Competition, Unfair South Africa , Wine industry South Africa Employees , Unfair labor practices South Africa , Fairtrade International , International trade , Economic development Moral and ethical aspects South Africa , Wine industry Moral and ethical aspects South Africa , Work environment South Africa
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/327155 , vital:61086 , DOI 10.21504/10962/327155
- Description: The South African wine industry is one of the oldest sectors of the country’s economy, beginning in the early years of South African colonialism in the 17th century through the use of slave and slave-like labour. As an industry that has been defined by farm paternalism and dependency, the South African wine industry has had to demonstrate changes from its history of extreme racial and gendered exploitation to an industry that reflects the democratic values of a new South Africa. Ethical certifications are considered one way through which the post-apartheid South African wine industry can demonstrate that it has moved away from its historical practices and is now characterised by practices of decent work and social transformation. An important certificatory label that allows local wine producers entry into global wine production networks is Fairtrade International. While Fairtrade certification is often reserved for small-scale producers, this certification has been extended to large-scale, commercial producers within the South African wine industry despite its history of farm paternalism and dependency. This research asks if this inclusion promotes decent work through social upgrading or if it offers a platform for the continuation of farm dependency under the guise of ‘Fairtrade’. In this study, social upgrading has been defined through a ‘bottom-up’ approach that prioritises workers’ independence as a key means of improvement. Four key pillars are applied as embodying the concept of social upgrading: regular employment with set working hours; legally enforceable worker rights; social protection through collective and individual bargaining power; and non-discriminatory social dialogue that promotes significant socio-economic progression. A key finding of this research is that practices of dependency and paternalism continue on some large-scale commercial farms, despite their Fairtrade certification. Furthermore, the findings suggest that the benefits that farmworkers receive lock farmworkers into their position on the farm with marginally improved conditions and cease if workers depart from the Fairtrade wine farm. This suggests that, at best, this inclusion of commercial farmers within Fairtrade certification appears to create a top-down form of social upgrading that locks farmworkers into their position on the farm with marginally improved conditions and beneath a glass ceiling of development. At worst, this Fairtrade inclusion facilitates a global poverty network through paternalism and dependency under the guise of ‘Fairtrade’. As a result, where meaningful, bottom-up social upgrading may occur on South African wine farms, the study suggests that this is despite the presence of Fairtrade and not a result of it. , Thesis (PhD) -- Faculty of Humanities, Political and Interntional Studies, 2022
- Full Text:
- Date Issued: 2022-10-14
The distribution and perceptions of invasive alien plants in small towns in the Eastern Cape province, South Africa
- Authors: Seboko, Tshepiso Collen
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/${Handle} , vital:65669
- Description: Invasive alien plants (IAP) of different life forms have major effects on biodiversity, ecosystem functioning, economies, and livelihoods worldwide. There is evidence that IAP are rapidly increasing around the world, and the negative impacts associated with them are expected to worsen due to continuing land transformation, climate change, and urbanisation. Yet, information on the distribution, abundance, knowledge, and perceptions of IAP is limited, especially in small towns. Most previous research has largely focused on rural settings and larger cities, thus hindering the effective control and management of IAP in smaller urban settings. It is therefore important to assess the distribution of IAP to provide useful information to guide clearing and mitigation efforts to reduce the impacts and proliferation of IAP in smaller urban settings. Consequently, the aim of the study was to determine the distribution, composition, abundance, and perceptions of woody IAP in small towns in the Eastern Cape province of South Africa and assess how and why they may differ within and between towns. To achieve this aim, a drive by road survey was undertaken across all suburbs and land use types in 12 small towns located in the Eastern Cape province of South Africa. The 12 randomly selected small towns were, Adelaide, Alexandria, Barkley East, Bedford, Burgersdorp, Cathcart, Kirkwood, Middelburg, Paterson, Somerset East, St. Francis Bay and Willowmore. All woody IAP visible from the surveyed roads were counted across all suburbs and land use types within each town. A total of 38 427 woody IAP were enumerated, with 56 species across different land use types and suburbs in all towns. Affluent suburbs accounted for 58% of the IAP enumerated, while the Reconstructed Development Programme (RDP) suburbs accounted for only 5%. In terms of the land use type, most of the IAP were encountered in the residential areas (54%), as compared to, road verges (32%) and public urban green spaces (PUGS) (14%). Of the 12 towns, Middleburg had the highest number of woody IAP, with 5 573 individuals, while Paterson had the lowest number with 947. The most common IAP species across all towns was Melia azedarach with 4 384 individuals, followed by Pinus elliotti (4 051), and Jacaranda mimosifolia (3 640). Spathodea campanulata, Ardisia crenata, and Parkinsonia aculeata had the lowest number of individuals with only two individuals each across all towns. This study also assessed the knowledge, perceptions, and willingness of urban residents to control IAP in their home yards using household surveys. A total of 240 household surveys were administered in the 12 towns. The results showed that more than half of the respondents (59%) had no knowledge of IAP, while 14% had neutral knowledge and only 2% had high knowledge. Forty percent of the respondents agreed that IAP pose a problem to the environment whilst 11% did not think IAP posed a problem to the environment, and 49% stated that they do not know. Most of the respondents (91%) perceived IAP positively, and stated that they benefit from the IAP, with the most mentioned benefit being shade (50%). Almost two-thirds of the respondents (65%) were willing to report on the IAP in their yards to the relevant authorities that deal with the control and management of IAP. Over half (56%) of the respondents were willing to have the IAP removed from their gardens, with the most stated reason for removal was because the IAP caused damage to property (13%). Respondents thought that the local government (35%) or district government (30%) should be responsible for the control and management of IAP. Overall, the study showed that IAP species were most common in residential land use type and affluent suburbs. These findings can assist the relevant authorities that deal with IAP, regarding which plant species, suburbs, and land use types to prioritise regarding awareness and investment for control and management. This will also help explore alternative indigenous species that can be used as replacements that may offer the same benefits derived from IAP by urban residents. , Thesis (MSc) -- Faculty of Science, Environmental Science, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Seboko, Tshepiso Collen
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/${Handle} , vital:65669
- Description: Invasive alien plants (IAP) of different life forms have major effects on biodiversity, ecosystem functioning, economies, and livelihoods worldwide. There is evidence that IAP are rapidly increasing around the world, and the negative impacts associated with them are expected to worsen due to continuing land transformation, climate change, and urbanisation. Yet, information on the distribution, abundance, knowledge, and perceptions of IAP is limited, especially in small towns. Most previous research has largely focused on rural settings and larger cities, thus hindering the effective control and management of IAP in smaller urban settings. It is therefore important to assess the distribution of IAP to provide useful information to guide clearing and mitigation efforts to reduce the impacts and proliferation of IAP in smaller urban settings. Consequently, the aim of the study was to determine the distribution, composition, abundance, and perceptions of woody IAP in small towns in the Eastern Cape province of South Africa and assess how and why they may differ within and between towns. To achieve this aim, a drive by road survey was undertaken across all suburbs and land use types in 12 small towns located in the Eastern Cape province of South Africa. The 12 randomly selected small towns were, Adelaide, Alexandria, Barkley East, Bedford, Burgersdorp, Cathcart, Kirkwood, Middelburg, Paterson, Somerset East, St. Francis Bay and Willowmore. All woody IAP visible from the surveyed roads were counted across all suburbs and land use types within each town. A total of 38 427 woody IAP were enumerated, with 56 species across different land use types and suburbs in all towns. Affluent suburbs accounted for 58% of the IAP enumerated, while the Reconstructed Development Programme (RDP) suburbs accounted for only 5%. In terms of the land use type, most of the IAP were encountered in the residential areas (54%), as compared to, road verges (32%) and public urban green spaces (PUGS) (14%). Of the 12 towns, Middleburg had the highest number of woody IAP, with 5 573 individuals, while Paterson had the lowest number with 947. The most common IAP species across all towns was Melia azedarach with 4 384 individuals, followed by Pinus elliotti (4 051), and Jacaranda mimosifolia (3 640). Spathodea campanulata, Ardisia crenata, and Parkinsonia aculeata had the lowest number of individuals with only two individuals each across all towns. This study also assessed the knowledge, perceptions, and willingness of urban residents to control IAP in their home yards using household surveys. A total of 240 household surveys were administered in the 12 towns. The results showed that more than half of the respondents (59%) had no knowledge of IAP, while 14% had neutral knowledge and only 2% had high knowledge. Forty percent of the respondents agreed that IAP pose a problem to the environment whilst 11% did not think IAP posed a problem to the environment, and 49% stated that they do not know. Most of the respondents (91%) perceived IAP positively, and stated that they benefit from the IAP, with the most mentioned benefit being shade (50%). Almost two-thirds of the respondents (65%) were willing to report on the IAP in their yards to the relevant authorities that deal with the control and management of IAP. Over half (56%) of the respondents were willing to have the IAP removed from their gardens, with the most stated reason for removal was because the IAP caused damage to property (13%). Respondents thought that the local government (35%) or district government (30%) should be responsible for the control and management of IAP. Overall, the study showed that IAP species were most common in residential land use type and affluent suburbs. These findings can assist the relevant authorities that deal with IAP, regarding which plant species, suburbs, and land use types to prioritise regarding awareness and investment for control and management. This will also help explore alternative indigenous species that can be used as replacements that may offer the same benefits derived from IAP by urban residents. , Thesis (MSc) -- Faculty of Science, Environmental Science, 2022
- Full Text:
- Date Issued: 2022-10-14
Drifting towards death: a South African patient safety incident through an HFE Systems lens
- Authors: Agar, Sarah Leigh
- Date: 2022-10-14
- Subjects: Patients Safety measures , Medical errors Prevention , Human engineering , Medical care South Africa
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362716 , vital:65356
- Description: Patient Safety Incidents (PSI) are a frequent occurrence within the South African public healthcare system wherein a patient is unnecessarily maimed, harmed, killed, or put through significant trauma, emotional or physical. These incidents have a significant impact on the performance of the system and the well-being of individuals involved. Often PSI are the result of multiple system failings that provide the necessary preconditions for the PSI to occur. Thus, to provide appropriate patient safety recommendations to address and aid in the prevention of future PSI it is necessary to apply a systems approach to PSI analysis. A systems approach supports a ‘bigger picture’ view of an incident which includes looking beyond the immediate causes of a PSI and taking the different levels of the healthcare system into consideration during incident analysis. Human Factors and Ergonomics (HFE) is at its core a systems discipline and has been successfully applied to multiple fields including healthcare. HFE offers multiple incident analysis tools grounded in systems theory. The Life Esidimeni incident, a PSI that resulted in the death of 144 MHCU, is the biggest PSI in recent South African history and is therefore an important potential case study for the application of HFE systems tools within the South African healthcare context (an area that is lacking in existing literature). The objectives of this research were to (i) Systematically uncover the causal factors that led to the outcome of the of the Life Esidimeni incident; (ii) Identify critical faults, and gaps within the healthcare system that led to the Life Esidimeni PSI; and (iii) Provide proactive recommendations for future prevention of PSI. To fulfil these objectives a descriptive case study research method design was adopted using a qualitative systems-based tool, AcciMap. The application of AcciMap to Life Esidimeni enabled both the sharp end and blunt end causal factors that contributed to the outcome of the incident to be identified. Importantly this provided insight into the critical faults and gaps of the South African public healthcare system. The results of the AcciMap indicated that there were four main broad systemic faults in the system. These broad areas were categorized as key themes, which include: (i) competency, (ii) safeguards, (iii) time pressures, and (iv) vertical integration. From these key themes recommendations aimed at addressing the critical faults and gaps in the system and preventing future PSI were made. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Agar, Sarah Leigh
- Date: 2022-10-14
- Subjects: Patients Safety measures , Medical errors Prevention , Human engineering , Medical care South Africa
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362716 , vital:65356
- Description: Patient Safety Incidents (PSI) are a frequent occurrence within the South African public healthcare system wherein a patient is unnecessarily maimed, harmed, killed, or put through significant trauma, emotional or physical. These incidents have a significant impact on the performance of the system and the well-being of individuals involved. Often PSI are the result of multiple system failings that provide the necessary preconditions for the PSI to occur. Thus, to provide appropriate patient safety recommendations to address and aid in the prevention of future PSI it is necessary to apply a systems approach to PSI analysis. A systems approach supports a ‘bigger picture’ view of an incident which includes looking beyond the immediate causes of a PSI and taking the different levels of the healthcare system into consideration during incident analysis. Human Factors and Ergonomics (HFE) is at its core a systems discipline and has been successfully applied to multiple fields including healthcare. HFE offers multiple incident analysis tools grounded in systems theory. The Life Esidimeni incident, a PSI that resulted in the death of 144 MHCU, is the biggest PSI in recent South African history and is therefore an important potential case study for the application of HFE systems tools within the South African healthcare context (an area that is lacking in existing literature). The objectives of this research were to (i) Systematically uncover the causal factors that led to the outcome of the of the Life Esidimeni incident; (ii) Identify critical faults, and gaps within the healthcare system that led to the Life Esidimeni PSI; and (iii) Provide proactive recommendations for future prevention of PSI. To fulfil these objectives a descriptive case study research method design was adopted using a qualitative systems-based tool, AcciMap. The application of AcciMap to Life Esidimeni enabled both the sharp end and blunt end causal factors that contributed to the outcome of the incident to be identified. Importantly this provided insight into the critical faults and gaps of the South African public healthcare system. The results of the AcciMap indicated that there were four main broad systemic faults in the system. These broad areas were categorized as key themes, which include: (i) competency, (ii) safeguards, (iii) time pressures, and (iv) vertical integration. From these key themes recommendations aimed at addressing the critical faults and gaps in the system and preventing future PSI were made. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2022
- Full Text:
- Date Issued: 2022-10-14
The incorporation of GeoGebra as a visualisation tool to teach calculus in teacher education institutions: the Zambian case
- Authors: Kangwa, Lemmy
- Date: 2022-10-14
- Subjects: GeoGebra , Calculus Study and teaching (Secondary) Zambia , Visual learning
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/405470 , vital:70174 , DOI
- Description: This qualitative case study investigated teacher educators’ (lecturers) use of the dynamic mathematics software, GeoGebra, to teach calculus in three teacher education institutions (TEIs) in Zambia. Visualisation, a key characteristic of GeoGebra, is increasingly gaining recognition of playing a critical role in mathematics teaching and learning, especially in problem solving tasks. It is considered a powerful didactical tool for students to construct mental and physical representations that can enhance conceptual understanding of mathematics. GeoGebra is a visualisation tool that can be used for problem-oriented teaching and foster mathematical experiments and discoveries. GeoGebra’s inherent visualisation characteristics align well with the teaching of calculus, the mathematical domain of this study. The study (whose research methodology was underpinned by the interpretive paradigm) was undertaken with a broader goal of designing and implementing GeoGebra applets and instructional materials on various calculus topics. The study is located within the “Teaching and Learning Mathematics with GeoGebra (TLMG) project” – a project that involves mathematics teachers and lecturers in Zambia. The case in this study is the six mathematics lecturers who co-designed and used GeoGebra applets to teach derivatives and integrals to pre-service mathematics teachers in TEIs. The unit of analysis therefore is the six lecturers’ use of GeoGebra as a visualisation tool to teach calculus to enhance conceptual understanding, their perceptions and experiences of using GeoGebra and the enabling and constraining factors of using GeoGebra to teach and learn mathematics. The data for the study were video recordings of observations and interviews of lecturers. The data was analysed thematically and was guided and informed by an analytical framework adopted from the theory of constructivism – the umbrella theoretical framework of this study – and the models of Technological Pedagogical Content Knowledge (TPACK), and the Technology Acceptance Model (TAM). A detailed analysis of the lecturers’ interactions with the applets enabled me to gain insights into the participants’ experiences and perceptions of GeoGebra applets in the teaching and learning process. The findings of the study revealed that the visualisation characteristics of GeoGebra generally enhanced the conceptual understanding of calculus. It also revealed that adequate training, coupled with sufficient knowledge of the subject matter in calculus, were necessary for lecturers to use GeoGebra effectively, and that the lack of resources and expertise were major hindrances in the use of GeoGebra to teach mathematics in TEIs. It also revealed that there is a need to equip GeoGebra with other features that would make it more versatile, and suggested a teaching approach that would complement the use of conventional methods and GeoGebra to provide a link between abstract and concrete concepts of calculus. , Thesis (PhD) -- Faculty of Education, Education, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Kangwa, Lemmy
- Date: 2022-10-14
- Subjects: GeoGebra , Calculus Study and teaching (Secondary) Zambia , Visual learning
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/405470 , vital:70174 , DOI
- Description: This qualitative case study investigated teacher educators’ (lecturers) use of the dynamic mathematics software, GeoGebra, to teach calculus in three teacher education institutions (TEIs) in Zambia. Visualisation, a key characteristic of GeoGebra, is increasingly gaining recognition of playing a critical role in mathematics teaching and learning, especially in problem solving tasks. It is considered a powerful didactical tool for students to construct mental and physical representations that can enhance conceptual understanding of mathematics. GeoGebra is a visualisation tool that can be used for problem-oriented teaching and foster mathematical experiments and discoveries. GeoGebra’s inherent visualisation characteristics align well with the teaching of calculus, the mathematical domain of this study. The study (whose research methodology was underpinned by the interpretive paradigm) was undertaken with a broader goal of designing and implementing GeoGebra applets and instructional materials on various calculus topics. The study is located within the “Teaching and Learning Mathematics with GeoGebra (TLMG) project” – a project that involves mathematics teachers and lecturers in Zambia. The case in this study is the six mathematics lecturers who co-designed and used GeoGebra applets to teach derivatives and integrals to pre-service mathematics teachers in TEIs. The unit of analysis therefore is the six lecturers’ use of GeoGebra as a visualisation tool to teach calculus to enhance conceptual understanding, their perceptions and experiences of using GeoGebra and the enabling and constraining factors of using GeoGebra to teach and learn mathematics. The data for the study were video recordings of observations and interviews of lecturers. The data was analysed thematically and was guided and informed by an analytical framework adopted from the theory of constructivism – the umbrella theoretical framework of this study – and the models of Technological Pedagogical Content Knowledge (TPACK), and the Technology Acceptance Model (TAM). A detailed analysis of the lecturers’ interactions with the applets enabled me to gain insights into the participants’ experiences and perceptions of GeoGebra applets in the teaching and learning process. The findings of the study revealed that the visualisation characteristics of GeoGebra generally enhanced the conceptual understanding of calculus. It also revealed that adequate training, coupled with sufficient knowledge of the subject matter in calculus, were necessary for lecturers to use GeoGebra effectively, and that the lack of resources and expertise were major hindrances in the use of GeoGebra to teach mathematics in TEIs. It also revealed that there is a need to equip GeoGebra with other features that would make it more versatile, and suggested a teaching approach that would complement the use of conventional methods and GeoGebra to provide a link between abstract and concrete concepts of calculus. , Thesis (PhD) -- Faculty of Education, Education, 2022
- Full Text:
- Date Issued: 2022-10-14
Big T’s and small T’s: an explorative study on trauma narratives in South Africa
- Authors: Naidoo, Rinisa
- Date: 2022-10-14
- Subjects: Psychic trauma , Anthropology , Mental health South Africa , Apartheid South Africa Personal narratives , Culture Psychological aspects
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/408641 , vital:70512
- Description: The 21st century has seen a dramatic increase in chronic non-infectious diseases, especially in the area of mental health. Medical anthropologists have seen a rise in the development of mental illnesses in both developed and developing nations. There is, however, little research conducted on trauma narratives that do not stem from political violence from an anthropological lens. South Africa has various understandings of trauma depending on the cultural context and it is crucial to examine these narratives as this provides vital information of the daily lived experiences of trauma survivors. Key themes draw on issues of trauma denialism, communicating distress, traumatic symptoms and the development of mental illnesses as a result of traumatic exposure. The data was analysed through Goffman’s (1959) Presentation of Self in Everyday Life illustrating various ways how survivors present themselves depending on the particular audience. This research employed both qualitative and quantitative research methods to gather a holistic understanding of trauma survivors. With the use of semi-structured interviews of Stressful Life Events Questionnaire coupled with observations of online support groups for trauma survivors, this research has provided rich ethnographic evidence of the impact that culture has on trauma narratives illustrating a clear normalcy of trauma present in South Africa. , Thesis (MSocSci) -- Faculty of Humanities, Anthropology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Naidoo, Rinisa
- Date: 2022-10-14
- Subjects: Psychic trauma , Anthropology , Mental health South Africa , Apartheid South Africa Personal narratives , Culture Psychological aspects
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/408641 , vital:70512
- Description: The 21st century has seen a dramatic increase in chronic non-infectious diseases, especially in the area of mental health. Medical anthropologists have seen a rise in the development of mental illnesses in both developed and developing nations. There is, however, little research conducted on trauma narratives that do not stem from political violence from an anthropological lens. South Africa has various understandings of trauma depending on the cultural context and it is crucial to examine these narratives as this provides vital information of the daily lived experiences of trauma survivors. Key themes draw on issues of trauma denialism, communicating distress, traumatic symptoms and the development of mental illnesses as a result of traumatic exposure. The data was analysed through Goffman’s (1959) Presentation of Self in Everyday Life illustrating various ways how survivors present themselves depending on the particular audience. This research employed both qualitative and quantitative research methods to gather a holistic understanding of trauma survivors. With the use of semi-structured interviews of Stressful Life Events Questionnaire coupled with observations of online support groups for trauma survivors, this research has provided rich ethnographic evidence of the impact that culture has on trauma narratives illustrating a clear normalcy of trauma present in South Africa. , Thesis (MSocSci) -- Faculty of Humanities, Anthropology, 2022
- Full Text:
- Date Issued: 2022-10-14
Profiling Rhodes University students’ substance use during the Covid-19 pandemic lockdown: comparing the AUDIT and CCAPS-62 substance abuse sub-scale
- Authors: Goosen, Jeslyn Chrismaré
- Date: 2022-10-14
- Subjects: College students Substance use South Africa Makhanda , College students Alcohol use South Africa Makhanda , College students Mental health South Africa Makhanda , College students Attitudes , College students Economic conditions , COVID-19 (Disease) , Rhodes University
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405974 , vital:70224
- Description: Students are vulnerable to academic distress and mental health concerns. Many struggle to effectively cope with the many demands placed on them from various factions; included but not limited to institutional demands, financial concerns, and parental expectations. With the most recent outbreak of the SARS-Co V-2 (better known as the COVID-19 pandemic) many students have struggled to effectively cope with the changes relating to the nationwide lockdown. Universities had to change the way in which they provide students with the necessary academic material, and many had to return to their familial homes. This had a deleterious effect on the way students performed their daily activities and coping. A rise in impaired mental health was noted. Many students used alcohol as a means of coping during this tumultuous and unprecedented time. Undergraduate students at Rhodes University were asked to complete a survey questionnaire via SurveyMonkey, an online survey service. Data was collected over a ten-day period during July 2020. The AUDIT and the CCAPS-62 Substance Use subscale were used to measure their alcohol intake during lockdown and results was compared. Results indicated a significant positive correlation between the CCAPS-62 substance use subscale and the AUDIT (r = 0.80, n = 930, p < 0.01). Outcomes identified that men tend to drink more than females, and white students tend to drink more than black students. Findings suggests that the CCAPS-62 a multidimensional instrument measuring general distress among students could positively contribute to the reliability and validity of the measure used in a multicultural and multilingual society such as South Africa. , Thesis (MA) -- Faculty of Humanities, Psychology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Goosen, Jeslyn Chrismaré
- Date: 2022-10-14
- Subjects: College students Substance use South Africa Makhanda , College students Alcohol use South Africa Makhanda , College students Mental health South Africa Makhanda , College students Attitudes , College students Economic conditions , COVID-19 (Disease) , Rhodes University
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405974 , vital:70224
- Description: Students are vulnerable to academic distress and mental health concerns. Many struggle to effectively cope with the many demands placed on them from various factions; included but not limited to institutional demands, financial concerns, and parental expectations. With the most recent outbreak of the SARS-Co V-2 (better known as the COVID-19 pandemic) many students have struggled to effectively cope with the changes relating to the nationwide lockdown. Universities had to change the way in which they provide students with the necessary academic material, and many had to return to their familial homes. This had a deleterious effect on the way students performed their daily activities and coping. A rise in impaired mental health was noted. Many students used alcohol as a means of coping during this tumultuous and unprecedented time. Undergraduate students at Rhodes University were asked to complete a survey questionnaire via SurveyMonkey, an online survey service. Data was collected over a ten-day period during July 2020. The AUDIT and the CCAPS-62 Substance Use subscale were used to measure their alcohol intake during lockdown and results was compared. Results indicated a significant positive correlation between the CCAPS-62 substance use subscale and the AUDIT (r = 0.80, n = 930, p < 0.01). Outcomes identified that men tend to drink more than females, and white students tend to drink more than black students. Findings suggests that the CCAPS-62 a multidimensional instrument measuring general distress among students could positively contribute to the reliability and validity of the measure used in a multicultural and multilingual society such as South Africa. , Thesis (MA) -- Faculty of Humanities, Psychology, 2022
- Full Text:
- Date Issued: 2022-10-14
The implementation of a mobile application to decrease occupational sitting through goal setting and social comparison
- Authors: Tsaoane, Moipone Lipalesa
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/365544 , vital:65758
- Description: Background: Feedback proves to be a valuable tool in behaviour change as it is said to increase compliance and improve the effectiveness of interventions. Interventions that focus on decreasing sedentary behaviour as an independent factor from physical activity are necessary, especially for office workers who spend most of their day seated. There is insufficient knowledge regarding the effectiveness of feedback as a tool to decrease sedentary behaviour. This project implemented a tool that can be used to determine this. To take advantage of the cost-effectiveness and scalability of digital technologies, a mobile application was selected as the mode of delivery. Method: The application was designed as an intervention, using the Theoretical Domains Framework. It was then implemented into a fully functioning application through an agile development process, using Xam- arin.Forms framework. Due to challenges with this framework, a second application was developed using the React Native framework. Pilot studies were used for testing, with the final one consisting of Rhodes University employees. Results: The Xamarin.Forms application proved to be unfeasible; some users experienced fatal errors and crashes. The React Native application worked as desired and produced accurate and consistent step count readings, proving feasible from a functionality standpoint. The agile methodology enabled the developer to focus on implementing and testing one component at a time, which made the development process more manageable. Conclusion: Future work must conduct empirical studies to determine if feedback is an effective tool compared to a control group and which type of feedback (between goal-setting and social comparison) is most effective. , Thesis (MSc) -- Faculty of Science, Computer Science, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Tsaoane, Moipone Lipalesa
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/365544 , vital:65758
- Description: Background: Feedback proves to be a valuable tool in behaviour change as it is said to increase compliance and improve the effectiveness of interventions. Interventions that focus on decreasing sedentary behaviour as an independent factor from physical activity are necessary, especially for office workers who spend most of their day seated. There is insufficient knowledge regarding the effectiveness of feedback as a tool to decrease sedentary behaviour. This project implemented a tool that can be used to determine this. To take advantage of the cost-effectiveness and scalability of digital technologies, a mobile application was selected as the mode of delivery. Method: The application was designed as an intervention, using the Theoretical Domains Framework. It was then implemented into a fully functioning application through an agile development process, using Xam- arin.Forms framework. Due to challenges with this framework, a second application was developed using the React Native framework. Pilot studies were used for testing, with the final one consisting of Rhodes University employees. Results: The Xamarin.Forms application proved to be unfeasible; some users experienced fatal errors and crashes. The React Native application worked as desired and produced accurate and consistent step count readings, proving feasible from a functionality standpoint. The agile methodology enabled the developer to focus on implementing and testing one component at a time, which made the development process more manageable. Conclusion: Future work must conduct empirical studies to determine if feedback is an effective tool compared to a control group and which type of feedback (between goal-setting and social comparison) is most effective. , Thesis (MSc) -- Faculty of Science, Computer Science, 2022
- Full Text:
- Date Issued: 2022-10-14
Identification of novel compounds against Plasmodium falciparum Cytochrome bc1 Complex inhibiting the trans-membrane electron transfer pathway: an In Silico study
- Authors: Chebon, Lorna Jemosop
- Date: 2022-10-14
- Subjects: Malaria , Plasmodium falciparum , Molecular dynamics , Antimalarials , Molecules Models , Docking , Cytochromes , Drug resistance , Computer simulation , Drugs Computer-aided design , System analysis
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/365666 , vital:65774 , DOI https://doi.org/10.21504/10962/365666
- Description: Malaria continues to be a burden globally with a myriad of challenges deterring eradication efforts. With most antimalarials facing drug resistance, such as atovaquone (ATQ), alternative compounds that can withstand resistance are warranted. The Plasmodium falciparum cytochrome b (PfCytb), a subunit of P. falciparum cytochrome bc1 complex, is a validated drug target. Structurally, cytochrome b, cytochrome c1, and iron sulphur protein (ISP) subunits form the catalytic domain of the protein complex having heme bL, heme bH and iron-sulphur [2FE-2S] cluster cofactors. These cofactos have redox centres to aid in the electron transfer (ET) process. These subunits promote ET mainly through the enzyme’s ubiquinol oxidation (Qo) and ubiquinone reduction (Qi) processes in the catalytic domain. ATQ drug has been used in the prevention and treatment of uncomplicated malaria by targeting PfCytb protein. Once the mitochondrial transmembrane ET pathway is inhibited, it causes a collapse in its membrane potential. Previously reported ATQ drug resistance has been associated with the point mutations Y268C, Y268N and Y268S. Thus, in finding alternatives to the ATQ drug, this research aimed to: i) employ in silico approaches incorporating protein into phospholipid bilayer for the first time to understand the parasites’ resistance mechanism; ii) determine any sequence and structural differences that could be explored in drug design studies; and iii) screen for PfCytb-iron sulphur protein (Cytb-ISP) hit compounds from South African natural compound database (SANCDB) and Medicines for Malaria Venture (MMV) that can withstand the identified mutations. Using computational tools, comparative sequence and structural analyses were performed on the cytochrome b protein, where the ultimate focus was on P. falciparum cytochrome b and its human homolog. Through multiple sequence alignment, motif discovery and phylogeny, differences between P. falciparum and H. sapiens cytochrome b were identified. Protein modelling of both P. falciparum and H. sapiens cytochrome b - iron sulphur protein (PfCytb-ISP and HsCytb-ISP) was performed. Results showed that at the sequence level, there were few amino acid residue differences because the protein is highly conserved. Important to note is the four-residue deletion in Plasmodium spp. absent in the human homolog. Motif analysis discovered five unique motifs in P. falciparum cytochrome b protein which were mapped onto the predicted protein model. These motifs were not in regions of functional importance; hence their function is still unknown. At a structural level, the four-residue deletion was observed to alter the Qo substrate binding pocket as reported in previous studies and confirmed in this study. This deletion resulted in a 0.83 Å structural displacement. Also, there are currently no in silico studies that have performed experiments with P. falciparum cytochrome b protein incorporated into a phospholipid bilayer. Using 350 ns molecular dynamics (MD) simulations of the holo and ATQ-bound systems, the study highlighted the resistance mechanism of the parasite protein where the loss of active site residue-residue interactions was identified, all linked to the three mutations. The identified compromised interactions are likely to destabilise the protein’s function, specifically in the Qo substrate binding site. This showed the possible effect of mutations on ATQ drug activity, where all three mutations were reported to share a similar resistance mechanism. Thereafter, this research work utilised in silico approaches where both Qo active site and interface pocket were targeted by screening the South African natural compounds database (SANCDB) and Medicines for Malaria Venture (MMV) compounds to identify novel selective hits. SANCDB compounds are known for their structural complexity that preserves the potency of the drug molecule. Both SANCDB and MMV compounds have not been explored as inhibitors against the PfCytb drug target. Molecular docking, molecular dynamics (MD) simulations, principal component, and dynamic residue network (DRN; global and local) analyses were utilised to identify and confirm the potential selective inhibitors. Docking results identified compounds that bound selectively onto PfCytb-ISP with a binding energy ≤ -8.7 kcal/mol-1. Further, this work validated a total of eight potential selective compounds to inhibit PfCytb-ISP protein (Qo active site) not only in the wild-type but also in the presence of the point mutations Y268C, Y268N and Y268S. The selective binding of these hit compounds could be linked to the differences reported at sequence/residue level in chapter 3. DRN and residue contact map analyses of the eight compounds in holo and ligand-bound systems revealed reduced residue interactions and decreased protein communication. This suggests that the eight compounds show the possibility of inhibiting the parasite and disrupting important residue-residue interactions. Additionally, 13 selective compounds were identified to bind at the protein’s heterodimer interface, where global and local analysis confirmed their effect on active site residues (distal location) as well as on the communication network. Based on the sequence differences between PfCytb and the human homolog, these findings suggest these selective compounds as potential allosteric modulators of the parasite enzyme, which may serve as possible replacements of the already resistant ATQ drug. Therefore, these findings pave the way for further in vitro studies to establish their anti-plasmodial inhibition levels. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Chebon, Lorna Jemosop
- Date: 2022-10-14
- Subjects: Malaria , Plasmodium falciparum , Molecular dynamics , Antimalarials , Molecules Models , Docking , Cytochromes , Drug resistance , Computer simulation , Drugs Computer-aided design , System analysis
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/365666 , vital:65774 , DOI https://doi.org/10.21504/10962/365666
- Description: Malaria continues to be a burden globally with a myriad of challenges deterring eradication efforts. With most antimalarials facing drug resistance, such as atovaquone (ATQ), alternative compounds that can withstand resistance are warranted. The Plasmodium falciparum cytochrome b (PfCytb), a subunit of P. falciparum cytochrome bc1 complex, is a validated drug target. Structurally, cytochrome b, cytochrome c1, and iron sulphur protein (ISP) subunits form the catalytic domain of the protein complex having heme bL, heme bH and iron-sulphur [2FE-2S] cluster cofactors. These cofactos have redox centres to aid in the electron transfer (ET) process. These subunits promote ET mainly through the enzyme’s ubiquinol oxidation (Qo) and ubiquinone reduction (Qi) processes in the catalytic domain. ATQ drug has been used in the prevention and treatment of uncomplicated malaria by targeting PfCytb protein. Once the mitochondrial transmembrane ET pathway is inhibited, it causes a collapse in its membrane potential. Previously reported ATQ drug resistance has been associated with the point mutations Y268C, Y268N and Y268S. Thus, in finding alternatives to the ATQ drug, this research aimed to: i) employ in silico approaches incorporating protein into phospholipid bilayer for the first time to understand the parasites’ resistance mechanism; ii) determine any sequence and structural differences that could be explored in drug design studies; and iii) screen for PfCytb-iron sulphur protein (Cytb-ISP) hit compounds from South African natural compound database (SANCDB) and Medicines for Malaria Venture (MMV) that can withstand the identified mutations. Using computational tools, comparative sequence and structural analyses were performed on the cytochrome b protein, where the ultimate focus was on P. falciparum cytochrome b and its human homolog. Through multiple sequence alignment, motif discovery and phylogeny, differences between P. falciparum and H. sapiens cytochrome b were identified. Protein modelling of both P. falciparum and H. sapiens cytochrome b - iron sulphur protein (PfCytb-ISP and HsCytb-ISP) was performed. Results showed that at the sequence level, there were few amino acid residue differences because the protein is highly conserved. Important to note is the four-residue deletion in Plasmodium spp. absent in the human homolog. Motif analysis discovered five unique motifs in P. falciparum cytochrome b protein which were mapped onto the predicted protein model. These motifs were not in regions of functional importance; hence their function is still unknown. At a structural level, the four-residue deletion was observed to alter the Qo substrate binding pocket as reported in previous studies and confirmed in this study. This deletion resulted in a 0.83 Å structural displacement. Also, there are currently no in silico studies that have performed experiments with P. falciparum cytochrome b protein incorporated into a phospholipid bilayer. Using 350 ns molecular dynamics (MD) simulations of the holo and ATQ-bound systems, the study highlighted the resistance mechanism of the parasite protein where the loss of active site residue-residue interactions was identified, all linked to the three mutations. The identified compromised interactions are likely to destabilise the protein’s function, specifically in the Qo substrate binding site. This showed the possible effect of mutations on ATQ drug activity, where all three mutations were reported to share a similar resistance mechanism. Thereafter, this research work utilised in silico approaches where both Qo active site and interface pocket were targeted by screening the South African natural compounds database (SANCDB) and Medicines for Malaria Venture (MMV) compounds to identify novel selective hits. SANCDB compounds are known for their structural complexity that preserves the potency of the drug molecule. Both SANCDB and MMV compounds have not been explored as inhibitors against the PfCytb drug target. Molecular docking, molecular dynamics (MD) simulations, principal component, and dynamic residue network (DRN; global and local) analyses were utilised to identify and confirm the potential selective inhibitors. Docking results identified compounds that bound selectively onto PfCytb-ISP with a binding energy ≤ -8.7 kcal/mol-1. Further, this work validated a total of eight potential selective compounds to inhibit PfCytb-ISP protein (Qo active site) not only in the wild-type but also in the presence of the point mutations Y268C, Y268N and Y268S. The selective binding of these hit compounds could be linked to the differences reported at sequence/residue level in chapter 3. DRN and residue contact map analyses of the eight compounds in holo and ligand-bound systems revealed reduced residue interactions and decreased protein communication. This suggests that the eight compounds show the possibility of inhibiting the parasite and disrupting important residue-residue interactions. Additionally, 13 selective compounds were identified to bind at the protein’s heterodimer interface, where global and local analysis confirmed their effect on active site residues (distal location) as well as on the communication network. Based on the sequence differences between PfCytb and the human homolog, these findings suggest these selective compounds as potential allosteric modulators of the parasite enzyme, which may serve as possible replacements of the already resistant ATQ drug. Therefore, these findings pave the way for further in vitro studies to establish their anti-plasmodial inhibition levels. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2022
- Full Text:
- Date Issued: 2022-10-14
Lateral and vertical mineral-chemical variation in high-grade ores of the Kalahari Manganese Field, and implications for ore genesis and geometallurgy
- Authors: Motilaodi, Donald
- Date: 2022-10-14
- Subjects: Manganese ores , Geometallurgy , Hydrothermal alteration , Petrology , Mineralogy , Geochemistry
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362972 , vital:65379
- Description: The Kalahari Manganese Field (KMF) is a world-class resource of manganese ore hosted by the Paleoproterozoic Hotazel banded iron formation. KMF ores are categorised into two main types, i.e., low-grade, carbonate rich, braunitic ore (Mn≤40wt%) and carbonate-free, high-grade, Ca-braunite+hausmannite ore (Mn≥44wt%). High-grade ores, also known as Wessels type from the homonymous mine in the northernmost KMF, are thought to have formed from variable degrees of hydrothermal carbonate and silica leaching from a low-grade ore precursor, termed Mamatwan-type after the homonymous mine in the southernmost KMF. This project aims to conduct a mineralogical and mineral-chemical study of representative manganese ore samples from a suite of drillcores intersecting both the upper and the lower layers in the northern KMF, covering the areas of Wessels, N’chwaning and Gloria mines. Petrographically, the high-grade Mn ore displays great variability in three-dimensional space. Texturally, the ores exhibit a great variety of textures which may or may not show preservation of the laminated and ovoidal textures that typify the postulated low-grade protore. There is also significant variation in the mineralogical and geochemical characteristics of the high-grade Mn ores both vertically and laterally. Vertical variation includes, probably for the first time, variability between the upper and lower ore layers within individual drillcores of the Hotazel sequence. Mineralogically, the ores contain variable modal abundances of the ore-forming minerals braunite (I, II, “new”) and hausmannite, and much less so of bixbyite, marokite and manganite. Common accessories include andradite, barite and low-Mn carbonate minerals. Chemically, the dominant ore minerals braunite and hausmannite, contain Fe up to 22 and 15wt% respectively, which accounts for the bulk of the iron contained in the ores. Braunite compositions also exhibit a large range with respect to their ratio of Ca/Si. Mineral-specific trace element concentrations for the same minerals measured by LA-ICP-MS, reveal generally large variations from one element to the other. When normalized against the trace element composition of bulk low-grade precursor ore, strong enrichments are recorded for both hausmannite and braunite in selected alkali/alkali earth elements, transition metals and lanthanides, such as Sc, Co, Zn, Cu, Pb, La, and Ce. These are akin to enrichments recorded in average high-grade ore. Although there is also no obvious relationship between Fe content in both hausmannite and braunite and their trace element abundances, the drillcore that captures high-grade ore with the highest trace element concentrations appears to be located most proximal to a major fault. Results collectively suggest that high-grade Mn ores of the KMF have undergone a complex hydrothermal history with a clear and significant metasomatic addition of trace elements into ore-forming minerals. First order trends in the mineralogical and mineral-chemical distribution of the ores in space, suggest hausmannite-dominated ores near the Hotazel suboutcrop, and an apparent decline in ore quality with braunite II-andradite-barite-calcite ores as the major graben fault is approached in a southwesterly direction. The latter trend appears to be at odds with prevailing fault-controlled alteration models. Elucidating that hydrothermal history of the Wessels-type high grade Mn ores of the KMF, will be crucial to understanding the compositional controls of these ores in space, and the potential impact thereof in terms of geometallurgy. , Thesis (MSc) -- Faculty of Science, Geology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Motilaodi, Donald
- Date: 2022-10-14
- Subjects: Manganese ores , Geometallurgy , Hydrothermal alteration , Petrology , Mineralogy , Geochemistry
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362972 , vital:65379
- Description: The Kalahari Manganese Field (KMF) is a world-class resource of manganese ore hosted by the Paleoproterozoic Hotazel banded iron formation. KMF ores are categorised into two main types, i.e., low-grade, carbonate rich, braunitic ore (Mn≤40wt%) and carbonate-free, high-grade, Ca-braunite+hausmannite ore (Mn≥44wt%). High-grade ores, also known as Wessels type from the homonymous mine in the northernmost KMF, are thought to have formed from variable degrees of hydrothermal carbonate and silica leaching from a low-grade ore precursor, termed Mamatwan-type after the homonymous mine in the southernmost KMF. This project aims to conduct a mineralogical and mineral-chemical study of representative manganese ore samples from a suite of drillcores intersecting both the upper and the lower layers in the northern KMF, covering the areas of Wessels, N’chwaning and Gloria mines. Petrographically, the high-grade Mn ore displays great variability in three-dimensional space. Texturally, the ores exhibit a great variety of textures which may or may not show preservation of the laminated and ovoidal textures that typify the postulated low-grade protore. There is also significant variation in the mineralogical and geochemical characteristics of the high-grade Mn ores both vertically and laterally. Vertical variation includes, probably for the first time, variability between the upper and lower ore layers within individual drillcores of the Hotazel sequence. Mineralogically, the ores contain variable modal abundances of the ore-forming minerals braunite (I, II, “new”) and hausmannite, and much less so of bixbyite, marokite and manganite. Common accessories include andradite, barite and low-Mn carbonate minerals. Chemically, the dominant ore minerals braunite and hausmannite, contain Fe up to 22 and 15wt% respectively, which accounts for the bulk of the iron contained in the ores. Braunite compositions also exhibit a large range with respect to their ratio of Ca/Si. Mineral-specific trace element concentrations for the same minerals measured by LA-ICP-MS, reveal generally large variations from one element to the other. When normalized against the trace element composition of bulk low-grade precursor ore, strong enrichments are recorded for both hausmannite and braunite in selected alkali/alkali earth elements, transition metals and lanthanides, such as Sc, Co, Zn, Cu, Pb, La, and Ce. These are akin to enrichments recorded in average high-grade ore. Although there is also no obvious relationship between Fe content in both hausmannite and braunite and their trace element abundances, the drillcore that captures high-grade ore with the highest trace element concentrations appears to be located most proximal to a major fault. Results collectively suggest that high-grade Mn ores of the KMF have undergone a complex hydrothermal history with a clear and significant metasomatic addition of trace elements into ore-forming minerals. First order trends in the mineralogical and mineral-chemical distribution of the ores in space, suggest hausmannite-dominated ores near the Hotazel suboutcrop, and an apparent decline in ore quality with braunite II-andradite-barite-calcite ores as the major graben fault is approached in a southwesterly direction. The latter trend appears to be at odds with prevailing fault-controlled alteration models. Elucidating that hydrothermal history of the Wessels-type high grade Mn ores of the KMF, will be crucial to understanding the compositional controls of these ores in space, and the potential impact thereof in terms of geometallurgy. , Thesis (MSc) -- Faculty of Science, Geology, 2022
- Full Text:
- Date Issued: 2022-10-14
Exploring integration for the topic of stoichiometry in South African natural sciences and physical sciences school curricula
- Authors: Mgolozeli, Kwanele
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405330 , vital:70162
- Description: Many developing countries, including South Africa, have identified the provision and implementation of strong science curricula as central to their developmental needs. Stoichiometry is a fundamental chemistry topic because the concepts involved form the basis of later topics such as chemical equilibrium, rates of reactions, redox reactions, and acid-base reactions. School students consistently demonstrate lack of understanding of stoichiometry-related concepts and skills such as the particulate nature of matter and related mathematical problem-solving. The poor performance of high school students in central science topics such as stoichiometry is problematic for their further study of chemistry and for the country meeting its need for science graduates. Successive examiner reports pointed to the lack of integration of stoichiometry concepts across the grades being the main problem. However, no study could be found which explores how stoichiometry is integrated in the South African Natural Sciences and Physical Sciences curriculum across the grades. This provided the rationale for the current study. The case study reported in this thesis thus aimed to explore integration of stoichiometry concepts in South African Natural Sciences and Physical Sciences school curricula. It involved document analysis as the method of collecting data. The research adopted the social realist paradigm, with its realist ontology and relativist epistemology. Legitimation Code Theory provided the theoretical framing. Chemistry concepts that are foundational to the understanding of stoichiometry according to literature, were chosen as root concepts for the concept mapping undertaken to identify types of integration. The concept maps revealed four stoichiometry integration themes: integration of stoichiometry concepts with symbols, integration of stoichiometry concepts with explanations, integration with applications in a chemistry context, and integration with an everyday context. These themes provided integration categories. A semantic gravity translation device was then developed for characterising the types of integration in terms of the degree of contextualisation. The results of this study show that stoichiometry integration of weaker semantic gravity is legitimated more strongly over other semantic gravity codes in the Natural Sciences and Physical Sciences curricula across all grade levels. While this has advantages in terms of knowledge-building potential, the consequence is that the integration occurs at very abstract levels that are far removed from learners’ everyday lives. The practical implication for curriculum developers involves increasing the instances of integration of stoichiometry concepts at stronger levels of semantic gravity, for a more even semantic gravity range of integration types. Natural Sciences and Physical Sciences teachers also need to source and include real-life examples for explanations and applications of stoichiometry concepts when teaching, in light of current curriculum documents focusing more on abstract forms of integration. Methodologically, this study contributes to the increased utility of semantic gravity through its exploration of integration in relation to knowledge-building potential of curriculum for hierarchical knowledge structures such as chemistry. , Thesis (MEd) -- Faculty of Education, Education, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Mgolozeli, Kwanele
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405330 , vital:70162
- Description: Many developing countries, including South Africa, have identified the provision and implementation of strong science curricula as central to their developmental needs. Stoichiometry is a fundamental chemistry topic because the concepts involved form the basis of later topics such as chemical equilibrium, rates of reactions, redox reactions, and acid-base reactions. School students consistently demonstrate lack of understanding of stoichiometry-related concepts and skills such as the particulate nature of matter and related mathematical problem-solving. The poor performance of high school students in central science topics such as stoichiometry is problematic for their further study of chemistry and for the country meeting its need for science graduates. Successive examiner reports pointed to the lack of integration of stoichiometry concepts across the grades being the main problem. However, no study could be found which explores how stoichiometry is integrated in the South African Natural Sciences and Physical Sciences curriculum across the grades. This provided the rationale for the current study. The case study reported in this thesis thus aimed to explore integration of stoichiometry concepts in South African Natural Sciences and Physical Sciences school curricula. It involved document analysis as the method of collecting data. The research adopted the social realist paradigm, with its realist ontology and relativist epistemology. Legitimation Code Theory provided the theoretical framing. Chemistry concepts that are foundational to the understanding of stoichiometry according to literature, were chosen as root concepts for the concept mapping undertaken to identify types of integration. The concept maps revealed four stoichiometry integration themes: integration of stoichiometry concepts with symbols, integration of stoichiometry concepts with explanations, integration with applications in a chemistry context, and integration with an everyday context. These themes provided integration categories. A semantic gravity translation device was then developed for characterising the types of integration in terms of the degree of contextualisation. The results of this study show that stoichiometry integration of weaker semantic gravity is legitimated more strongly over other semantic gravity codes in the Natural Sciences and Physical Sciences curricula across all grade levels. While this has advantages in terms of knowledge-building potential, the consequence is that the integration occurs at very abstract levels that are far removed from learners’ everyday lives. The practical implication for curriculum developers involves increasing the instances of integration of stoichiometry concepts at stronger levels of semantic gravity, for a more even semantic gravity range of integration types. Natural Sciences and Physical Sciences teachers also need to source and include real-life examples for explanations and applications of stoichiometry concepts when teaching, in light of current curriculum documents focusing more on abstract forms of integration. Methodologically, this study contributes to the increased utility of semantic gravity through its exploration of integration in relation to knowledge-building potential of curriculum for hierarchical knowledge structures such as chemistry. , Thesis (MEd) -- Faculty of Education, Education, 2022
- Full Text:
- Date Issued: 2022-10-14
Mechanistic analysis of two cytotoxic thiazolidinones as novel inhibitors of Triple-Negative Breast Cancer
- Authors: Vukea, Nyeleti
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/365734 , vital:65780
- Description: Thesis embargoes. Expected release date early 2025. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Vukea, Nyeleti
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/365734 , vital:65780
- Description: Thesis embargoes. Expected release date early 2025. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2022
- Full Text:
- Date Issued: 2022-10-14
The development of teachers’ pedagogical content knowledge (PCK) in the mediation of chemical equilibrium: A formative interventionist study
- Authors: Manamike, Tasara
- Date: 2022-10-14
- Subjects: Chemical equilibrium , Chemistry Study and teaching (Secondary) Nambia , Expansive learning , Career development Nambia , Professional learning communities Nambia , Pedagogical content knowledge , Cultural-historical activity theory
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405300 , vital:70159
- Description: Persistent student errors in understanding chemical equilibrium as shown by poor student achievement in national examinations reflect student difficulties in learning and deficiencies in teaching methodologies. Studies which have been conducted in Namibia have explored the teaching of chemical equilibrium and revealed that teachers seem not to have adequate pedagogical content knowledge (PCK) for mediating chemical equilibrium and therefore there is a need for continuing professional development (CPD). However, it seems the CPD facilitators also find this topic difficult and are unsure of which methods are really effective owing to the disagreements among teachers and researchers. In addition, current CPD practices ostensibly fail to address the teachers’ needs because the facilitators have their own commitments and accountabilities and may ignore teachers’ contexts. It is against this backdrop that I conducted this formative interventionist study to improve teachers’ PCK for mediating chemical equilibrium through expansive learning (learning something that does not yet exist). A blend of the interpretivist and critical paradigm underpinned this study, which assumed a transactional epistemology. The qualitative case study research design was used to gather in-depth information about the multiple realities of the participants, bearing in mind that teaching is idiosyncratic, and the teaching approaches or strategies employed heavily depend on the contexts. Accordingly, the cultural historical activity theory was used to guide the teachers’ activities during the intervention for generating the data which were analysed using the topic-specific pedagogical content knowledge. The study revealed that the participants faced challenges in their teaching, namely: (i) students’ difficulties with comprehension and (ii) teachers’ instructional problems or deficiencies in instructional skills. The findings also revealed that the intervention enabled the participants to collectively transform their practices and therefore address the major challenges in their practices, that is, they expansively learnt how to effectively teach chemical equilibrium. , Thesis (MEd) -- Faculty of Education, Education, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Manamike, Tasara
- Date: 2022-10-14
- Subjects: Chemical equilibrium , Chemistry Study and teaching (Secondary) Nambia , Expansive learning , Career development Nambia , Professional learning communities Nambia , Pedagogical content knowledge , Cultural-historical activity theory
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405300 , vital:70159
- Description: Persistent student errors in understanding chemical equilibrium as shown by poor student achievement in national examinations reflect student difficulties in learning and deficiencies in teaching methodologies. Studies which have been conducted in Namibia have explored the teaching of chemical equilibrium and revealed that teachers seem not to have adequate pedagogical content knowledge (PCK) for mediating chemical equilibrium and therefore there is a need for continuing professional development (CPD). However, it seems the CPD facilitators also find this topic difficult and are unsure of which methods are really effective owing to the disagreements among teachers and researchers. In addition, current CPD practices ostensibly fail to address the teachers’ needs because the facilitators have their own commitments and accountabilities and may ignore teachers’ contexts. It is against this backdrop that I conducted this formative interventionist study to improve teachers’ PCK for mediating chemical equilibrium through expansive learning (learning something that does not yet exist). A blend of the interpretivist and critical paradigm underpinned this study, which assumed a transactional epistemology. The qualitative case study research design was used to gather in-depth information about the multiple realities of the participants, bearing in mind that teaching is idiosyncratic, and the teaching approaches or strategies employed heavily depend on the contexts. Accordingly, the cultural historical activity theory was used to guide the teachers’ activities during the intervention for generating the data which were analysed using the topic-specific pedagogical content knowledge. The study revealed that the participants faced challenges in their teaching, namely: (i) students’ difficulties with comprehension and (ii) teachers’ instructional problems or deficiencies in instructional skills. The findings also revealed that the intervention enabled the participants to collectively transform their practices and therefore address the major challenges in their practices, that is, they expansively learnt how to effectively teach chemical equilibrium. , Thesis (MEd) -- Faculty of Education, Education, 2022
- Full Text:
- Date Issued: 2022-10-14
Don’t let the little man live in your head for free: an interpretive phenomenological analysis of seafarers with reportedly high levels of well-being
- Authors: Brown, Lauren Natalie
- Date: 2022-10-14
- Subjects: Seafaring life Psychological aspects , Sailors Mental health , Well-being , Phenomenology , Work environment
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/327653 , vital:61140 , DOI 10.21504/10962/327653
- Description: The mental health of seafarers has become a growing issue of concern and has attracted the attention of researchers in recent times. Seafarers are predominantly men, spend months at sea with little to no contact with loved ones ashore, and usually must reside in confined spaces that often contain substantial levels of noise and heat. The underlying causes of mental illness among seafarers are known. Some of the causes include sleep deprivation, occupational stress, marital/relationship problems, fatigue, the threat of piracy, psychosocial workload, loneliness, social isolation, separation from families, lack of shore leave, cultural issues, and job security. Despite these stressors, there are many men and women seafarers who flourish in the industry and enjoy their careers. Very little research has been conducted into the well-being practices of those seafarers who enjoy high levels of well-being. This study explores the lived experiences of a group of seafarers with reportedly high levels of psychological well-being, as well as their experiences of workplace stressors and mental health interventions offered by the industry. This study is an interpretive phenomenological analysis, which is epistemologically underpinned by phenomenology, hermeneutics and idiography. Results revealed four focus areas: general lived experiences across two worlds and how this relates to identity, what seafarers with reportedly high levels of psychological well-being experience as stressors, well-being practices of these seafarers and how these seafarers experience and make sense of mental health interventions they have come across. , Thesis (PhD) -- Faculty of Humanities, Psychology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Brown, Lauren Natalie
- Date: 2022-10-14
- Subjects: Seafaring life Psychological aspects , Sailors Mental health , Well-being , Phenomenology , Work environment
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/327653 , vital:61140 , DOI 10.21504/10962/327653
- Description: The mental health of seafarers has become a growing issue of concern and has attracted the attention of researchers in recent times. Seafarers are predominantly men, spend months at sea with little to no contact with loved ones ashore, and usually must reside in confined spaces that often contain substantial levels of noise and heat. The underlying causes of mental illness among seafarers are known. Some of the causes include sleep deprivation, occupational stress, marital/relationship problems, fatigue, the threat of piracy, psychosocial workload, loneliness, social isolation, separation from families, lack of shore leave, cultural issues, and job security. Despite these stressors, there are many men and women seafarers who flourish in the industry and enjoy their careers. Very little research has been conducted into the well-being practices of those seafarers who enjoy high levels of well-being. This study explores the lived experiences of a group of seafarers with reportedly high levels of psychological well-being, as well as their experiences of workplace stressors and mental health interventions offered by the industry. This study is an interpretive phenomenological analysis, which is epistemologically underpinned by phenomenology, hermeneutics and idiography. Results revealed four focus areas: general lived experiences across two worlds and how this relates to identity, what seafarers with reportedly high levels of psychological well-being experience as stressors, well-being practices of these seafarers and how these seafarers experience and make sense of mental health interventions they have come across. , Thesis (PhD) -- Faculty of Humanities, Psychology, 2022
- Full Text:
- Date Issued: 2022-10-14
Electrocatalytic activity of symmetric and asymmetric Co(II) and Mn(III) porphyrins in the presence of graphene quantum dots towards the oxidation of hydrazine
- Authors: Jokazi, Mbulelo
- Date: 2022-10-14
- Subjects: Electrocatalysis , Hydrazine , Quantum dots , Graphene , Porphyrins
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362894 , vital:65372
- Description: The influence of metal porphyrins in electro-oxidation of hydrazine is explored. A series of symmetric and asymmetric porphyrins alone and in the presence of graphene quantum dots (GQDs) are employed in this work. Tetra 4-aminophenyl porphyrin, manganese tetra 4-aminophenyl porphyrin, manganese tetra 4-aminophenyl porphyrin--GQDs, and manganese tetra 4-aminophenyl porphyrin@GQDs are the symmetric porphyrins. The asymmetric porphyrin and composites are 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins, manganese 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins, cobalt 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins, manganese 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins--GQDs, and cobalt 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins--GQDs. These complexes were synthesized and characterized accordingly and applied for electrocatalysis. The electrocatalytic experiments were carried out using glassy carbon electrode and the modification was through drop-dry method. The porphyrin and GQDs synthesized were characterized using UV-Vis spectroscopy, Mass spectrometry, X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and energy dispersive x-ray spectroscopy. The modified electrodes were characterized using cyclic voltammetry and electrochemical Impedance spectroscopy. The introduction of metal ion in the center of the porphyrin improved electrocatalysis. The presence of push-pull substituents in the porphyrin lowered the oxidation potential and improved the catalysis. The presence of GQDs improved catalysis in both symmetric and asymmetric porphyrin compared to individual components. Cobalt porphyrins showed better activity than manganese porphyrin. , Thesis (MSc) -- Faculty of Science, Chemistry, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Jokazi, Mbulelo
- Date: 2022-10-14
- Subjects: Electrocatalysis , Hydrazine , Quantum dots , Graphene , Porphyrins
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362894 , vital:65372
- Description: The influence of metal porphyrins in electro-oxidation of hydrazine is explored. A series of symmetric and asymmetric porphyrins alone and in the presence of graphene quantum dots (GQDs) are employed in this work. Tetra 4-aminophenyl porphyrin, manganese tetra 4-aminophenyl porphyrin, manganese tetra 4-aminophenyl porphyrin--GQDs, and manganese tetra 4-aminophenyl porphyrin@GQDs are the symmetric porphyrins. The asymmetric porphyrin and composites are 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins, manganese 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins, cobalt 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins, manganese 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins--GQDs, and cobalt 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins--GQDs. These complexes were synthesized and characterized accordingly and applied for electrocatalysis. The electrocatalytic experiments were carried out using glassy carbon electrode and the modification was through drop-dry method. The porphyrin and GQDs synthesized were characterized using UV-Vis spectroscopy, Mass spectrometry, X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and energy dispersive x-ray spectroscopy. The modified electrodes were characterized using cyclic voltammetry and electrochemical Impedance spectroscopy. The introduction of metal ion in the center of the porphyrin improved electrocatalysis. The presence of push-pull substituents in the porphyrin lowered the oxidation potential and improved the catalysis. The presence of GQDs improved catalysis in both symmetric and asymmetric porphyrin compared to individual components. Cobalt porphyrins showed better activity than manganese porphyrin. , Thesis (MSc) -- Faculty of Science, Chemistry, 2022
- Full Text:
- Date Issued: 2022-10-14
The meanings of the social media practices of African women engaged in multi-level marketing in Makhanda
- Authors: Tembani, Khuselwa Anda
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/365588 , vital:65762
- Description: In their efforts for a place in the economy, many South African women have embraced opportunities in the informal sector such as selling products for big Multi-Level Marketers (MLMs), who generally operate on a pyramid structure of commissions. This qualitative study investigates the meanings African women engaged in MLMs in Makhanda make of such work and examines how they construct notions of progress and success through their social media practices. The study was conducted in the strictest lockdown period and pioneered a research method that used Zoom to facilitate screen sharing on mobile phones to create an online version of the scroll-back method for Facebook. As expected for women working in a society increasingly integrated in a global neoliberal order, many of the meanings the women construct are rooted in neoliberal discourses that celebrate hyper-individualism and competition. This firstly includes constructing success through personal stories of self-appreciation, through which these women embody the MLM’s brand, while simultaneously improving their position in the market as sellers. Secondly, the women invest considerable effort on social media in constructing MLM work as epitomising stability in the context of the growing precarity that characterises their everyday lives. However, other meanings draw on the local African context. Here the women make sense of the inequalities that characterise the MLM pyramid structures, by constructing top players in the upline as a symbolic vanguard trailblazing freedom from a racist past through showcasing paths out of poverty. More interestingly, success is constructed as both resulting from and serving collective ways of being rooted in the discourse of African humanism. Here success is recognised as emerging from dense place-based networks in the neighbourhood built on trust and obligation, now replicated on social media. In conclusion, the study speculates that the worlds of meaning facilitated by MLMs might provide ways for neoliberal and traditional discourses to find points of synergy, and so serve as entry points into a neoliberal order that interestingly nevertheless draws on communal cultures of obligation and patronage. , Thesis (MA) -- Faculty of Humanities, School of Journalism and Media Studies, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Tembani, Khuselwa Anda
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/365588 , vital:65762
- Description: In their efforts for a place in the economy, many South African women have embraced opportunities in the informal sector such as selling products for big Multi-Level Marketers (MLMs), who generally operate on a pyramid structure of commissions. This qualitative study investigates the meanings African women engaged in MLMs in Makhanda make of such work and examines how they construct notions of progress and success through their social media practices. The study was conducted in the strictest lockdown period and pioneered a research method that used Zoom to facilitate screen sharing on mobile phones to create an online version of the scroll-back method for Facebook. As expected for women working in a society increasingly integrated in a global neoliberal order, many of the meanings the women construct are rooted in neoliberal discourses that celebrate hyper-individualism and competition. This firstly includes constructing success through personal stories of self-appreciation, through which these women embody the MLM’s brand, while simultaneously improving their position in the market as sellers. Secondly, the women invest considerable effort on social media in constructing MLM work as epitomising stability in the context of the growing precarity that characterises their everyday lives. However, other meanings draw on the local African context. Here the women make sense of the inequalities that characterise the MLM pyramid structures, by constructing top players in the upline as a symbolic vanguard trailblazing freedom from a racist past through showcasing paths out of poverty. More interestingly, success is constructed as both resulting from and serving collective ways of being rooted in the discourse of African humanism. Here success is recognised as emerging from dense place-based networks in the neighbourhood built on trust and obligation, now replicated on social media. In conclusion, the study speculates that the worlds of meaning facilitated by MLMs might provide ways for neoliberal and traditional discourses to find points of synergy, and so serve as entry points into a neoliberal order that interestingly nevertheless draws on communal cultures of obligation and patronage. , Thesis (MA) -- Faculty of Humanities, School of Journalism and Media Studies, 2022
- Full Text:
- Date Issued: 2022-10-14
Production of mannooligosaccharides from pineapple pulp and pine sawdust using Aspergillus niger derived Man26A and determination of their prebiotic effect
- Authors: Hlalukana, Nosipho Pretty
- Date: 2022-10-14
- Subjects: Oligosaccharides , Prebiotics , Lignocellulose , Mannans
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362853 , vital:65368
- Description: Lignocellulosic biomass is the most abundant source of renewable biomass on earth. Lignocellulosic biomass consists of cellulose, hemicelluloses and lignin. These can be used as a source of renewable fuel as well as other value-added products . Mannans are part of the hemicellulose fraction of lignocellulosic biomass and are the major hemicellulosic polysaccharide fraction in softwoods, where they are found as galactoglucomannans and as glucomannans. Mannans are also found in hardwoods in the form of glucomannans. Mannans can be enzymatically hydrolysed using endo-mannanases to produce of short chain mannooligosaccharides (MOS). MOS have received significant attention for their prebiotic properties, as they promote the growth of probiotic bacteria, which have positively affects on gut health. This study focused on the production of prebiotic MOS from lignocellulosic biomass waste (LBW) and an evaluation of the prebiotic potential of the produced MOS. An Aspergillus niger derived endo-mannanase, Man26A, was fractionated and biochemically analysed. Purified Man26A had a fold purification of 1.25 and a yield of 41.1%. SDS-PAGE analysis of the enzyme revealed that it had a molecular weight of 46 kDa. The pH and temperature optima of Man26A were determined and the pH optimum was found to be pH 4.0 (but the enzyme displayed high activity over a broad acidic pH range, with up to 90% of the activity retained between pH 3.0 and 7.0). The temperature optimum was 50℃. The enzyme was shown to have the highest specific activity on locust bean gum (52.27 U/mg) and ivory nut mannan (57.25 U/mg), compared to guar gum (29.07 U/mg), which indicated that it was affected by the substitution pattern of the mannans. Man26A produced MOS of different diversity on model mannan substrates, where the MOS produced were mannobiose, mannotriose, and mannotetraose for ivory nut mannan, mannobiose, mannotriose, mannotetraose, and mannopentaose and MOS with a higher degree of polymerisation for locust bean gum, and mannobiose, mannotriose, mannotetraose, mannopentaose, and mannohexose and MOS with a higher degree of polymerisation for guar gum, as determined by thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Pretreatment and characterisation of pineapple pulp (PP) and pine sawdust (PSD) was conducted, and the impact of the pretreatment procedures was analysed using Megazyme sugar kits, thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and microscopic analysis using scanning electron microscopy (SEM) and light microscopy. Compositional analysis of the carbohydrates present in both substrates revealed that they had a glucan content of 36.41 and 50.47% for untreated PP and PSD, respectively. Their respective mannan content was 6.74 and 11.59% and was deemed sufficient for the production of MOS via enzymatic hydrolysis. TGA analysis revealed that untreated and sodium chlorite-acetic acid delignified samples decomposed at approximately the same time, and had a negligible ash content at 600℃, while delignified plus phosphoric acid swollen substrates decomposed at a faster rate, but had a residual ash content at 600℃. FTIR analysis of the substrates revealed slight changes in the structures of untreated and pretreated samples. SEM analysis of PP and PSD showed a change in the morphology of the substrates with subsequent pretreatment steps. Histochemical analysis for lignin for PP and PSD showed successful delignification upon pretreatment. Untreated and sodium chlorite delignified PP and PSD released low amounts of reducing sugars compared to delignified + phosphoric acid swollen substrates. The delignified + phosphoric acid swollen substrates were used for further experiments. MOS produced from delignified and phosphoric acid swollen (Del + PAS) PP and PSD at 0.1 mg/ml enzyme loading and 80 mg/ml (8% (w/v)) substrate concentration, ran between mannose and mannobiose and between mannobiose and manotriose on TLC, with low concentrations of MOS running between mannotetraose and mannopentaose. HPLC analysis of the MOS revealed that Del + PAS PP produced mannose to mannohexose, while Del + PAS PSD produced mannose, mannobiose, and mannotetraose. The MOS were analysed using FTIR, to determine whether the MOS produced contained any acetyl groups, which were present for Del + PAS PSD at 1706 cm-1. The MOS were stable at different pHs, and at temperatures below 200℃. The MOS were also found to be stable in a simulated gastrointestinal environment, in the presence of bile salts and digestive enzymes. The prebiotic effect of the MOS derived from Del + PAS PP and PSD was evaluated. MOS had a proliferative effect on probiotic bacteria (Lactobacillus bulgaricus, Bacillus subtilis and Streptococcus thermophilus). The production of short chain fatty acids (SCFAs) was evaluated on TLC, where no SCFAs were observed on the plate. The effect of MOS on the adhesion ability of bacteria revealed that they do not positively influence the adhesion of probiotic bacteria. The antioxidant activities of 1 mg/ml MOS produced from both substrates were determined to be approximately 15% using the ABTS radical scavenging assay, compared to a radical scavenging activity of 45% for the 0.02 mg/ml gallic acid standard. This study demonstrated that biomass waste could be used to produce prebiotic MOS, which play a positive role in gut ecology and provide health benefits. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Hlalukana, Nosipho Pretty
- Date: 2022-10-14
- Subjects: Oligosaccharides , Prebiotics , Lignocellulose , Mannans
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362853 , vital:65368
- Description: Lignocellulosic biomass is the most abundant source of renewable biomass on earth. Lignocellulosic biomass consists of cellulose, hemicelluloses and lignin. These can be used as a source of renewable fuel as well as other value-added products . Mannans are part of the hemicellulose fraction of lignocellulosic biomass and are the major hemicellulosic polysaccharide fraction in softwoods, where they are found as galactoglucomannans and as glucomannans. Mannans are also found in hardwoods in the form of glucomannans. Mannans can be enzymatically hydrolysed using endo-mannanases to produce of short chain mannooligosaccharides (MOS). MOS have received significant attention for their prebiotic properties, as they promote the growth of probiotic bacteria, which have positively affects on gut health. This study focused on the production of prebiotic MOS from lignocellulosic biomass waste (LBW) and an evaluation of the prebiotic potential of the produced MOS. An Aspergillus niger derived endo-mannanase, Man26A, was fractionated and biochemically analysed. Purified Man26A had a fold purification of 1.25 and a yield of 41.1%. SDS-PAGE analysis of the enzyme revealed that it had a molecular weight of 46 kDa. The pH and temperature optima of Man26A were determined and the pH optimum was found to be pH 4.0 (but the enzyme displayed high activity over a broad acidic pH range, with up to 90% of the activity retained between pH 3.0 and 7.0). The temperature optimum was 50℃. The enzyme was shown to have the highest specific activity on locust bean gum (52.27 U/mg) and ivory nut mannan (57.25 U/mg), compared to guar gum (29.07 U/mg), which indicated that it was affected by the substitution pattern of the mannans. Man26A produced MOS of different diversity on model mannan substrates, where the MOS produced were mannobiose, mannotriose, and mannotetraose for ivory nut mannan, mannobiose, mannotriose, mannotetraose, and mannopentaose and MOS with a higher degree of polymerisation for locust bean gum, and mannobiose, mannotriose, mannotetraose, mannopentaose, and mannohexose and MOS with a higher degree of polymerisation for guar gum, as determined by thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Pretreatment and characterisation of pineapple pulp (PP) and pine sawdust (PSD) was conducted, and the impact of the pretreatment procedures was analysed using Megazyme sugar kits, thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and microscopic analysis using scanning electron microscopy (SEM) and light microscopy. Compositional analysis of the carbohydrates present in both substrates revealed that they had a glucan content of 36.41 and 50.47% for untreated PP and PSD, respectively. Their respective mannan content was 6.74 and 11.59% and was deemed sufficient for the production of MOS via enzymatic hydrolysis. TGA analysis revealed that untreated and sodium chlorite-acetic acid delignified samples decomposed at approximately the same time, and had a negligible ash content at 600℃, while delignified plus phosphoric acid swollen substrates decomposed at a faster rate, but had a residual ash content at 600℃. FTIR analysis of the substrates revealed slight changes in the structures of untreated and pretreated samples. SEM analysis of PP and PSD showed a change in the morphology of the substrates with subsequent pretreatment steps. Histochemical analysis for lignin for PP and PSD showed successful delignification upon pretreatment. Untreated and sodium chlorite delignified PP and PSD released low amounts of reducing sugars compared to delignified + phosphoric acid swollen substrates. The delignified + phosphoric acid swollen substrates were used for further experiments. MOS produced from delignified and phosphoric acid swollen (Del + PAS) PP and PSD at 0.1 mg/ml enzyme loading and 80 mg/ml (8% (w/v)) substrate concentration, ran between mannose and mannobiose and between mannobiose and manotriose on TLC, with low concentrations of MOS running between mannotetraose and mannopentaose. HPLC analysis of the MOS revealed that Del + PAS PP produced mannose to mannohexose, while Del + PAS PSD produced mannose, mannobiose, and mannotetraose. The MOS were analysed using FTIR, to determine whether the MOS produced contained any acetyl groups, which were present for Del + PAS PSD at 1706 cm-1. The MOS were stable at different pHs, and at temperatures below 200℃. The MOS were also found to be stable in a simulated gastrointestinal environment, in the presence of bile salts and digestive enzymes. The prebiotic effect of the MOS derived from Del + PAS PP and PSD was evaluated. MOS had a proliferative effect on probiotic bacteria (Lactobacillus bulgaricus, Bacillus subtilis and Streptococcus thermophilus). The production of short chain fatty acids (SCFAs) was evaluated on TLC, where no SCFAs were observed on the plate. The effect of MOS on the adhesion ability of bacteria revealed that they do not positively influence the adhesion of probiotic bacteria. The antioxidant activities of 1 mg/ml MOS produced from both substrates were determined to be approximately 15% using the ABTS radical scavenging assay, compared to a radical scavenging activity of 45% for the 0.02 mg/ml gallic acid standard. This study demonstrated that biomass waste could be used to produce prebiotic MOS, which play a positive role in gut ecology and provide health benefits. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2022
- Full Text:
- Date Issued: 2022-10-14
The role of visualisation in redefining the pedagogy of fractions in mathematics classrooms among senior primary school teachers
- Authors: Ausiku, Charity Makwiliro
- Date: 2022-10-14
- Subjects: Mathematics Study and teaching (Elementary) Namibia , Fractions Study and teaching (Elementary) Namibia , Visualization , Visual learning , Dual-coding hypothesis , Constructivism (Education) Namibia
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/405456 , vital:70173 , DOI 10.21504/10962/405456
- Description: This mixed methods study explored the impact of the use of a visualisation approach on the pedagogy of eight teacher participants who were involved in the Rundu Campus Fraction Project (RCFP). The aim of this study was to determine the extent to which participants incorporated visualisation processes in the pedagogy of fractions, in view of their exposure to visualisation activities in the RCFP. Since fractions are difficult to teach and learn, visualisation was considered as an alternative approach to the pedagogy of fractions because it presents learners with opportunities to improve their proportional and spatial reasoning. This study was founded on the premise that the incorporation of both verbal and nonverbal cues can enhance the teaching and learning of fractions rather than the use of a single cue. Hence, the two theories underpinning this study are the Dual Coding Theory and the Constructivist Theory. While the Dual Coding Theory advocates for the use of verbal and nonverbal codes, the Constructivist theory states that meaningful learning occurs when learners are presented with opportunities to construct their own knowledge. Thus, the two codes are intertwined. In other words, the active construction of knowledge among learners is aided by using constructivist teaching approaches through the incorporation of both verbal and nonverbal codes. Although this study was predominantly qualitative, quantitative methods were also used in the data collection process. A questionnaire was administered to identify teacher participants for this study, based on their teaching orientations. Their views on best practices in mathematics classrooms in general and the incorporation of visualisation processes in particular, were instrumental in the selection of participants for this study. In addition, observations and semi-structured interviews were also used as research methods. Twenty-five lesson samples were video recorded, transcribed and analysed using both qualitative and quantitative methods. Moreover, each of the eight participants was exposed to a set of pre- and post-observation interviews during which they were expected to express their views on the selection, incorporation and impact of visualisation processes on the teaching of fractions. Data sets from all three instruments were analysed using both quantitative and qualitative methods. The findings indicate that the RCFP had an impact on the teaching strategies employed by the participants as they all incorporated visualisation processes into their teaching to some extent. In some lessons, the visual code was effectively blended into the verbal code while in others, the purpose of and connection between the two codes was not evident. Hence, although all the participants embraced the incorporation of visualisation in the pedagogy of mathematics, some of them struggled to find its rightful position in the teaching of fractions. The findings suggest that despite the participants’ eagerness to use visualisation in their fraction lessons, some of them did not have adequate knowledge to successfully merge it with the conventional verbal code. Thus, for the integration of visuals to be impactful, it should be carefully merged in the teaching of fractions by taking into account various factors. , Thesis (PhD) -- Faculty of Education, Education, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Ausiku, Charity Makwiliro
- Date: 2022-10-14
- Subjects: Mathematics Study and teaching (Elementary) Namibia , Fractions Study and teaching (Elementary) Namibia , Visualization , Visual learning , Dual-coding hypothesis , Constructivism (Education) Namibia
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/405456 , vital:70173 , DOI 10.21504/10962/405456
- Description: This mixed methods study explored the impact of the use of a visualisation approach on the pedagogy of eight teacher participants who were involved in the Rundu Campus Fraction Project (RCFP). The aim of this study was to determine the extent to which participants incorporated visualisation processes in the pedagogy of fractions, in view of their exposure to visualisation activities in the RCFP. Since fractions are difficult to teach and learn, visualisation was considered as an alternative approach to the pedagogy of fractions because it presents learners with opportunities to improve their proportional and spatial reasoning. This study was founded on the premise that the incorporation of both verbal and nonverbal cues can enhance the teaching and learning of fractions rather than the use of a single cue. Hence, the two theories underpinning this study are the Dual Coding Theory and the Constructivist Theory. While the Dual Coding Theory advocates for the use of verbal and nonverbal codes, the Constructivist theory states that meaningful learning occurs when learners are presented with opportunities to construct their own knowledge. Thus, the two codes are intertwined. In other words, the active construction of knowledge among learners is aided by using constructivist teaching approaches through the incorporation of both verbal and nonverbal codes. Although this study was predominantly qualitative, quantitative methods were also used in the data collection process. A questionnaire was administered to identify teacher participants for this study, based on their teaching orientations. Their views on best practices in mathematics classrooms in general and the incorporation of visualisation processes in particular, were instrumental in the selection of participants for this study. In addition, observations and semi-structured interviews were also used as research methods. Twenty-five lesson samples were video recorded, transcribed and analysed using both qualitative and quantitative methods. Moreover, each of the eight participants was exposed to a set of pre- and post-observation interviews during which they were expected to express their views on the selection, incorporation and impact of visualisation processes on the teaching of fractions. Data sets from all three instruments were analysed using both quantitative and qualitative methods. The findings indicate that the RCFP had an impact on the teaching strategies employed by the participants as they all incorporated visualisation processes into their teaching to some extent. In some lessons, the visual code was effectively blended into the verbal code while in others, the purpose of and connection between the two codes was not evident. Hence, although all the participants embraced the incorporation of visualisation in the pedagogy of mathematics, some of them struggled to find its rightful position in the teaching of fractions. The findings suggest that despite the participants’ eagerness to use visualisation in their fraction lessons, some of them did not have adequate knowledge to successfully merge it with the conventional verbal code. Thus, for the integration of visuals to be impactful, it should be carefully merged in the teaching of fractions by taking into account various factors. , Thesis (PhD) -- Faculty of Education, Education, 2022
- Full Text:
- Date Issued: 2022-10-14
Exploration of remote work and wellbeing of academics in a South African tertiary institution
- Authors: Chikutu, Michelle
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405963 , vital:70223
- Description: Thesis embargoed. To be released in 2024. , Thesis (MA) -- Faculty of Humanities, Psychology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Chikutu, Michelle
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405963 , vital:70223
- Description: Thesis embargoed. To be released in 2024. , Thesis (MA) -- Faculty of Humanities, Psychology, 2022
- Full Text:
- Date Issued: 2022-10-14
An investigation into water and sanitation in the Eastern Cape Province and potential for implementation of biotechnology platforms
- Authors: Gumunyu, Wilbert
- Date: 2022-10-14
- Subjects: Sewage South Africa Eastern Cape , Sanitation South Africa Eastern Cape , Algae Biotechnology , Biotechnology , Sewage Purification Biological treatment , Algal biofuels
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362830 , vital:65366
- Description: In contemporary South Africa, a country in transition, destruction rather than reconstruction seems commonplace. Electricity supply is at an all-time low and ‘load shedding’ is an almost daily occurrence. Similarly, more fragility of water delivery and sanitation service is being reported with the likelihood of ‘water shedding’ a soon-to-be reality. In view of the ever-increasing reported mismanagement of South Africa’s water and sanitation infrastructure, which is likely nearing the point of collapse if not already collapsed, this thesis set out to interrogate at a provincial and municipal level the status of water and sanitation in Chris Hani District Municipality (CHDM), Eastern Cape Province. One major driver behind this study was to evaluate provincial and municipal water/wastewater infrastructure as a platform to support implementation of locally developed bioprocess technologies. First, publicly available historical data was used to derive a baseline or benchmark from which to determine gains/losses in compliance, water quality and efficiency. The period 2009-2013/4 during which Blue and Green Drop reporting was routine, was used as an appropriate start point. Data thus derived indicated that, at provincial and district municipality (DM) level, potable water supply was by bulk water schemes and, sanitation was typically by waste stabilization pond (WSP) treatment of municipal sewage. The derived benchmark for the period 2009-2013/14 indicated that most plants were not compliant (~75% of the Eastern Cape Province water treatment plants (WTP) operating between average performance to critical state), operated either at- or above design capacity (Eastern Cape Province, 16%; CHDM, 19%). A large number of plants for the province (62.4%) and district (81.25%) had hydraulic design capacity or average daily flows that were unknown (information not provided in available literature or plant reports) and final effluent did not always meet the general standard (70.3% of the CHDM wastewater treatment works (WWTW)). To determine the contemporary state (2020 - 2022) of water and sanitation within CHDM, a scoping exercise of WTP and WWTW in selected local municipalities was carried out. This was done along a west-east transect by appraising WTP and WWTW in the towns of Cradock, Tarkastad, Komani, Tsomo, Cacadu, and Ngcobo. Furthermore, targeted assessment of the Queenstown WTP and the Cradock WWTW was used to derive real-time data on the status of water and sanitation infrastructure. Results showed that water and sanitation services within CHDM had, in the years between 2009-2013/14 to date, deteriorated. Freshwater demand significantly exceeded capability of water supply schemes, where demand was as much as three times greater than reported available supply. For most WWTW, operation was in excess of capacity and between 1.52 and 12 times installed hydraulic loading. The targeted scoping exercise revealed that Queenstown WTP is a moderate risk plant (Cumulative risk rating, CRR = 11 and maximum risk rating, MRR = 47.8%), whereas Cradock WWTW was in working condition but with challenges and some infrastructural dysfunction. Assessment of water/effluent quality revealed that turbidity and TOC were above SANS 241 general limit. Non-compliance in terms of nitrate/nitrite-N, ammonium-N, phosphate-P, TSS, total coliforms, E. Coli, and free chlorine was evident at Cradock WWTW. Unstructured interviews with plant operators corroborated these findings. The overwhelming support for bulk schemes for potable water provision and WSP for sanitation indicated a partially water secure municipal district but derelict in terms of its sanitation services. The later, it was concluded, in particular provides an ideal opportunity for implementation of platform technologies to support bioprocesses for entrepreneurship, employment, economic benefit and to secure a closed circular economy for regional water and sanitation through valorisation of co-product streams. Among the co-product streams considered in this thesis are biomass, biogas, biofertilizers, biofuels and several high value chemical products. , Thesis (MSc) -- Faculty of Science, Institute for Environmental Biotechnology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Gumunyu, Wilbert
- Date: 2022-10-14
- Subjects: Sewage South Africa Eastern Cape , Sanitation South Africa Eastern Cape , Algae Biotechnology , Biotechnology , Sewage Purification Biological treatment , Algal biofuels
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362830 , vital:65366
- Description: In contemporary South Africa, a country in transition, destruction rather than reconstruction seems commonplace. Electricity supply is at an all-time low and ‘load shedding’ is an almost daily occurrence. Similarly, more fragility of water delivery and sanitation service is being reported with the likelihood of ‘water shedding’ a soon-to-be reality. In view of the ever-increasing reported mismanagement of South Africa’s water and sanitation infrastructure, which is likely nearing the point of collapse if not already collapsed, this thesis set out to interrogate at a provincial and municipal level the status of water and sanitation in Chris Hani District Municipality (CHDM), Eastern Cape Province. One major driver behind this study was to evaluate provincial and municipal water/wastewater infrastructure as a platform to support implementation of locally developed bioprocess technologies. First, publicly available historical data was used to derive a baseline or benchmark from which to determine gains/losses in compliance, water quality and efficiency. The period 2009-2013/4 during which Blue and Green Drop reporting was routine, was used as an appropriate start point. Data thus derived indicated that, at provincial and district municipality (DM) level, potable water supply was by bulk water schemes and, sanitation was typically by waste stabilization pond (WSP) treatment of municipal sewage. The derived benchmark for the period 2009-2013/14 indicated that most plants were not compliant (~75% of the Eastern Cape Province water treatment plants (WTP) operating between average performance to critical state), operated either at- or above design capacity (Eastern Cape Province, 16%; CHDM, 19%). A large number of plants for the province (62.4%) and district (81.25%) had hydraulic design capacity or average daily flows that were unknown (information not provided in available literature or plant reports) and final effluent did not always meet the general standard (70.3% of the CHDM wastewater treatment works (WWTW)). To determine the contemporary state (2020 - 2022) of water and sanitation within CHDM, a scoping exercise of WTP and WWTW in selected local municipalities was carried out. This was done along a west-east transect by appraising WTP and WWTW in the towns of Cradock, Tarkastad, Komani, Tsomo, Cacadu, and Ngcobo. Furthermore, targeted assessment of the Queenstown WTP and the Cradock WWTW was used to derive real-time data on the status of water and sanitation infrastructure. Results showed that water and sanitation services within CHDM had, in the years between 2009-2013/14 to date, deteriorated. Freshwater demand significantly exceeded capability of water supply schemes, where demand was as much as three times greater than reported available supply. For most WWTW, operation was in excess of capacity and between 1.52 and 12 times installed hydraulic loading. The targeted scoping exercise revealed that Queenstown WTP is a moderate risk plant (Cumulative risk rating, CRR = 11 and maximum risk rating, MRR = 47.8%), whereas Cradock WWTW was in working condition but with challenges and some infrastructural dysfunction. Assessment of water/effluent quality revealed that turbidity and TOC were above SANS 241 general limit. Non-compliance in terms of nitrate/nitrite-N, ammonium-N, phosphate-P, TSS, total coliforms, E. Coli, and free chlorine was evident at Cradock WWTW. Unstructured interviews with plant operators corroborated these findings. The overwhelming support for bulk schemes for potable water provision and WSP for sanitation indicated a partially water secure municipal district but derelict in terms of its sanitation services. The later, it was concluded, in particular provides an ideal opportunity for implementation of platform technologies to support bioprocesses for entrepreneurship, employment, economic benefit and to secure a closed circular economy for regional water and sanitation through valorisation of co-product streams. Among the co-product streams considered in this thesis are biomass, biogas, biofertilizers, biofuels and several high value chemical products. , Thesis (MSc) -- Faculty of Science, Institute for Environmental Biotechnology, 2022
- Full Text:
- Date Issued: 2022-10-14