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An investigation on the effects of Afrocentric missense variations on the structure and function of CYP2A6 protein
Full text linkPharmacogenomics, the foundation of personalized medicine distinguishes patients into different categories based on their response to the risk of a disease. Cytochrome P450 (CYPs) proteins are a family of enzymes critical in the metabolism of drugs and other substances. Genetic polymorphisms in CYPs can result in different enzymatic activity in individuals influencing the efficacy and toxicity of drugs. One of the CYPs which primarily metabolizes nicotine and other pharmaceutical drugs such as Artemisinin and Artesunate, Pilocarpine, Valproic Acid and Letrozole is CYP2A6. The gene encoding the protein is highly polymorphic and this can affect the rate of metabolism of drugs in individuals. Previously most studies unveiled connections between CYP2A6 variants and nicotine. Implications concerning the effects of specific missense variations in CYP2A6 drug metabolism have deficiencies. This study aimed to critically examine the structural and functional implications of 13 CYP2A6 allele variations on CYP2A6 protein using Bioinformatics techniques. Methods used were template selection, mutagenesis, parameter assignment and protonation. Molecular Dynamics to get insights regarding protein behavior at an atomic level, clustering to identify conformations during a simulation and DSSP for secondary structure analysis to monitor how secondary structures evolve. Berendsen and Parinello-Rahman barostats at production run were used for comparison. A global analysis was conducted to identify structural transitions (RMSD, RMSF, and Rg), clustering, and secondary structure prediction. Results from Berendsen barostat were inconsistent compared to Parrinello-Rahman barostat implying that CYP2A6 is sensitive to the pressure coupling parameter for precise and accurate results. Our clustering results showed each system in one conformation, fluctuations and shifts on the C-D, H-I loops and F, G, and L helices on variants I149M, F118l, K476R, and E390K_N418D_E419D. This indicated a potential loss of function limiting the protein’s ability to conformational flexibility for catalysis and substrate recognition. Certain regions of CYP2A6 became more rigid due to variations, which could have a negative impact on the catalytic activity, regulatory interactions, and general function of the enzyme in metabolism. Globally the variations did not cause large changes to the protein, there is need for a local analysis using Dynamic Residue Networks to study how residue interactions affect the function of CYP2A6.Thesis (MSc) -- Faculty of Science, Biochemistry, Microbiology and Bioinformatics, 202
Mbonalelo kha vhurangaphanda ha vhafumakadzi: young Vhavenḓa women’s views on their traditional leadership roles historically and post-1994
No full textThis is a qualitative research study that examines how young Vhavenḓa women in post-apartheid South Africa views different traditional leadership roles that Vhavenḓa women have historically played and continue to play in Venḓa society. Therefore, the research question that this Master of Arts (MA) research study sought to research is the following: How do young, 21st-century Vhavenḓa women view the traditional leadership roles historically and currently held by Vhavenḓa women in Vhavenḓa society? To grapple with this research question, this study employed a combination of purposive and snowball sampling strategies to recruit seven research participants. Research participants were interviewed using a semi-structured interview approach, which allowed the researcher to build rapport with research participants. Data was manually coded into five themes, namely: 1) The Role of Makhadzi in Traditional Leadership Among the Venḓa Community, 2) The Role of Vhakoma in Traditional Leadership Among the Venḓa Community, 3) The Role of Vhakololo in Traditional Leadership Among the Venḓa Community, 4) The customary practice of male primogeniture and how it contradicts the South African Constitution post-1994, and 5) The socialisation process that puts boys and men on a leadership pedestal. The data was then analysed and discussed in Chapters Four and Five through an Africana Womanist theoretical framework. An important finding in this study is that makhadzi, the father’s sister and also a woman who is a custodian of traditional leadership, is the traditional role that all the participants recognised as the leadership role that Vhavenḓa women have historically played and continue to play. Another role identified by participants as significant within the Venḓa leadership structure is Vhakoma, the Queen Mother and the chief's mother. However, there was limited familiarity with the role of Vhakololo, the royal members or people born into the royal family, as only one participant identified it as a leadership role traditionally occupied by Vhavenḓa women. Research participants suggested that colonial modernity contributes to a lack of knowledge about their culture. Another important finding of this study is that in post-1994 South Africa, there has been a tension between customary practices such as male primogeniture and the South African Constitution. Consequently, some women leaders have used the courts to challenge this practice. Ultimately, this study contributes to the discourse about women’s empowerment and the dismantling of patriarchal structures that undermine women's potential as leaders in the Venḓa context.Thesis (MA) -- Faculty of Humanities, Political and International Studies, 202
The emergence of classical worlds from a quantum universe
Full text linkHow does a classical world emerge from a quantum world? Can this emergence occur without invoking non-unitary processes such as measurements? Recently, an approach that makes use of just a Hilbert space and the associated Hamiltonian to explain the emergence of a classical world has been proposed. To understand this approach, we will require a clear understanding of the nature of measurements in quantum theory and the different interpretations of it. We then progress onto discussions regarding quantum Darwinism and related _elds of knowledge and how they \bypass" the problem of measurement in quantum theory. Then, we discuss how, using the appropriate choice of factorization of a Hilbert space into a system and an environment and using an acceptable basis observable, we can obtain a quasi-classical state of a system. This approach has previously been applied to study one limit (when interactions dominate the Hamiltonian), but we generalize by applying it to the opposite limit (when interactions are minimal) and suggest a method for the general case (when interactions are neither minimal nor dominant). We then look at Hilbert space fundamentalism, which is the idea that a vector in Hilbert space is the fundamental nature of reality. Hilbert space fundamentalism is a generalized application that takes the idea of the emergence of a classical world from a quantum one and applies it to the Universe as a whole. This leads to the question: could Hilbert space fundamentalism be a candidate for the fundamental theory? Before we evaluate Hilbert space fundamentalism as a candidate fundamental theory, we analyze the theory and inquire as to what makes something a fundamental theory. To understand Hilbert space fundamentalism, we see what a model of the world it predicts looks like. This is done by proposing a mapping from a fundamental Hilbert space to emergent space times utilizing entanglement and the aforementioned recently proposed approach that makes use of Hilbert spaces and Hamiltonians to explain the emergence of classical worlds. To determine if Hilbert space fundamentalism could be a fundamental theory, a set of criteria (completeness in all domains, self-contained, and that speci_c theories emerge from it) is noted. We find that Hilbert space fundamentalism, when viewed through these criteria, cannot be the fundamental theory.Thesis (MSc) -- Faculty of Science, Physics and Electronics, 202
Exploring the impact of sub-ambient CO2 concentrations on Oxalis growth: implications for food sustainability among Pleistocene human foragers in the Greater Cape Floristic Region
Full text linkHumans inhabiting the glacial refugia of the Cape Floristic Region during the Middle Pleistocene are believed to have relied on underground storage organs (USOs) as a crucial carbohydrate source. While previous research has highlighted the nutritional potential of these plants for early human gatherers, such studies are typically conducted under modern climatic conditions and do not account for the reduced plant productivity and USO yields associated with the lower atmospheric CO₂ concentrations characteristic of Pleistocene glacial periods. To evaluate the impact of CO₂ availability on plant productivity, I cultivated two Oxalis species—O. pes-caprae and O. punctata, both known to have been harvested by early foragers—under CO₂ concentrations ranging from 180 ppm to 400 ppm. Results showed that glacial-level CO₂ concentrations significantly reduced bulb production in O. pes-caprae and photosynthetic rates in both species. Using these findings to model Pleistocene foraging behaviour, I estimate that human foragers would have needed to spend an additional 8 hours gathering food to meet their daily dietary requirements of 2000 calories, suggesting the need for alternative food sources to supplement their diet. These findings emphasise the importance of considering historical plant growth conditions, particularly atmospheric CO₂ levels, when reconstructing past human diets. Failure to account for these factors may represent a significant gap in our understanding of human subsistence strategies during glacial periods.Thesis (MSc) -- Faculty of Science, Botany, 202
Transformative learning in geography education: international perspectives and practices
Full text linkThis paper critically reflects on how transformative learning (TL) is described both conceptually and as a process in the literature in different fields and national contexts. We articulate a definition of TL and justify why geography education is an ideal vehicle for enabling it. This is followed by a series of case studies explaining how TL can be and is being implemented in the curriculum topic of climate change in different countries. The findings of the analysis of the case studies are used to make propositions for further development and enactment of TL in geography education. The insights provided by this paper may help to move the field forward by opening new avenues of research and providing opportunities for cultivating a stronger geography education voice in global discourses about the types of learning required in a time of socio-ecological crisis and rapid societal change. Furthermore, it may provide practical ideas for improving learning and enhancing teaching practices which curriculum developers, learning resource producers, and practitioners may find useful
Bridging cultures in science education: leveraging lesson study approach for indigenous knowledge integration in a township school
Full text linkThe South African Curriculum Assessment and Policy Statement (CAPS) encourages science teachers to use culturally responsive pedagogies in their teaching. This should be done by integrating Indigenous Knowledge (IK) in science teaching to make it accessible and relevant to learners. However, the policy falls short of giving clear details on how this ought to be done. For instance, the school textbooks hardly contain any IK and there are few or no readily available teaching resources either. To complicate matters, many science teachers have not been trained on how to integrate IK into science teaching. As a result, most of them do not integrate any IK during their science lessons. It is against this backdrop that this study aimed to leverage the use of a Lesson Study approach when working with science teachers on how to integrate IK to mediate learning of the topics of waves and sound and redox reactions in a township school. Underpinned by the indigenous research and transformative paradigms, a qualitative case study approach in a form of participatory action research was adopted. Six science teachers from a township school, five Indigenous Knowledge Custodians1 (IKCs), one critical friend (isiXhosa and English teacher from the same school) and three university lecturers and a school principal from Zambia who conducted various workshops, and I were the participants in this study. Qualitative data was generated using interviews (semi-structured and stimulated recall interviews), document analysis, workshop discussions, observations (participatory and classroom observations) and journal reflections. Vygotsky’s sociocultural theory, Shulman’s pedagogical content knowledge, specifically Topic-specific Pedagogical Content Knowledge (TSPCK) and Ogunniyi’s Contiguity Argumentation Theory (CAT) were used as complementary theoretical frameworks. A thematic approach to data analysis was employed to come up with sub-themes and themes. The main findings of the study revealed that through collaboration with Indigenous Knowledge Custodians and tapping into their cultural heritage the integration of IK into science lessons was possible. Thus, this study showed that leveraging the use of a Lesson Study approach when working with science teachers on how to integrate IK to mediate learning of the topics of waves and sound and redox reactions in a township school, shifted the science teachers’ Zone of Proximal Development and Pedagogical Content Knowledge positively. Also, this study revealed that the integration of IK promotes learner talk or argumentation. Moreover, the use of isiXhosa our home language proved to be an invaluable cultural tool for effective communication in this study. The study thus recommends that transformational professional learning communities (PLCs) be established in township schools and that teachers should work in collaboration with IKCs to learn about IK which could be integrated into other science topics. Furthermore, the study recommends that teachers should be trained in document analysis and how to use the TSPCK components to unpack the curriculum. This might help the teachers to understand the curriculum needs better, plan better, and hopefully teach better. Thus, the contention of this study is that teacher preparedness is inextricably linked to learner achievement.Thesis (PhD) -- Faculty of Education, Secondary and Post School Education, 202
Three decades of change: exploring colonial legacies and shifts within processes of admission at South African Universities of Technology
Full text linkGiven South Africa’s complex legacy of inequality, access to higher education remains a priority for the government, higher education institutions and the public. And while significant progress has been made in terms of increased participation and expanded opportunities, particularly at Universities of Technology (UoTs), disparities remain. This particular type of institution has played a key role in contributing to the redress agenda through their less stringent admission requirements, but they remain underexamined in broader higher education literature. Despite these contributions, marginalised or working-class communities in rural and impoverished areas continue to face significant challenges in accessing higher education. Set against a global backdrop where similar patterns of admission have emerged, it becomes important to understand how and why the processes of admission in UoTs have emerged through the last three decades. In so doing, this study seeks to contribute to the conversation around social justice in higher education, offering insights that could reshape the understanding of why things are the way they are. This study draws on Critical Realism more broadly and the tools of Social Realism specifically to explore how South Africa’s particular colonial legacy remains one of many hidden mechanisms on which we build our reality. Using various documentation and qualitative data generated through interviews, which was analysed using Social Realism’s morphogenetic framework, I have endeavoured to tell the story of how, Universities of Technologies and their processes of admission have changed over the last three decades. In so doing I have shown, through using a metaphor of ‘The House Modernity Built’ how although much change has happened, hidden structures and cultures have worked to maintain a certain status quo, thereby constraining redress. This study has outlined the emergence of UoTs and their processes of admission as we understand them today. Through this I have presented an argument which suggests that the higher education sector continues to be structured in a hierarchical manner with UoTs located at the bottom. Mechanisms manifesting from a broader neoliberal environment, such as the higher education funding formula and global university ranking systems have placed UoTs in a position where they need to ‘catch up’, having consequences on the way in which processes of admission have been conceptualised. This has seen English becoming a marker of quality, and diploma offerings being replaced with degree equivalents carrying higher admission criteria, all of which work to compromise the redress needed in South African higher education.Thesis (PhD) -- Faculty of Education, Centre for Higher Education Research, Teaching and Learning, 202
Mainstreaming equitable decision-making under uncertainty at the Water User Association level using a reallocation model in the Western Cape, South Africa
Full text linkThis thesis demonstrates how uncertainty can be explicitly incorporated into equitable decision-making in ungauged basins to support fair water reallocation strategies among conflicting uses and reduce vulnerability to water shortages. First, a methodological framework is developed to collect the required socio-economic data. Second, a role-playing game (RPG) is developed in collaboration with stakeholders to increase awareness and assess the implications of different allocation strategies and stakeholder actions. Thirdly, a reallocation decision-support system (Water-Sharing Tool) with dam storage and uncertainty is tested to inform strategic water planning under dry conditions. The study was carried out in collaboration with stakeholders in the upper reaches of the Koue Bokkeveld, Western Cape, South Africa. The study area is a winter rainfall area with commercial farming activities targeting the domestic and cross-border markets. Irrigation from numerous farm dams and run-of-river extraction compete with in-stream environmental protection targets for streamflow. The study area can be described as resource-poor in terms of institutional capacity, with water management decisions taken individually at a farm level. The key water users are the environment, farmers, lifestyle farmers (residents), and weekenders. The farmer group has three sub-groups: corporate-owned farms, family-owned commercial farms, and downstream less well-resourced farmers. Results from the user risk profiles show that the least influential actors reside downstream and are more vulnerable to water shortages, which could be attributed to upstream developments and their productivity-driven nature. The thesis pulls together the socio-economic data, the information contributed by the stakeholders during the RPG, uncertain natural runoff estimates, and water demands. It evaluates these using the Water Sharing Model to map water users’ vulnerability under four different management strategies and assesses equitable reallocation outcomes of the proposed strategies to different users. The magnitude and frequency of decision risks and the underlying uncertainty in the water supply are quantified. As expected, results suggest peak risks during months with the lowest streamflow, with negative implications for fruit production in the catchment. Results also showed the negative supply effects of upstream infrastructure development on downstream users and ecosystems. Game results with the farmers suggested different crop choices in dry periods between upstream and downstream farmers. Downstream farmers were surprisingly more willing to forego their dry season entitlements under water-sharing strategies that resulted in serious production losses upstream, prioritising social stability over their own profits. Farmers reflected on the game as an educational tool to enhance system understanding. The study confirms that decision-makers' understanding of the implications of water allocation decisions and the surrounding uncertainty is critical to meeting justice/fairness objectives.Thesis (PhD) -- Faculty of Science, Institute for Water Research, 202
Stimulating Namibian learners’ democratic participation and leadership in a senior primary rural school: a participatory action research study
Full text linkThis study investigates the democratic participation and leadership opportunities of primary school learners within the Namibian education system, as outlined in the Basic Education Act. 3 of 2020. While the Act emphasises the involvement of secondary school learners in decision making, primary school learners are largely overlooked. Despite policies recognising children as democratic participants in education, implementation remains inconsistent, with secondary school learners often restricted to tokenistic leadership roles. To address this imbalance, the study explores leadership opportunities for primary school learners, seeking to understand the underlying factors contributing to the gap in democratic leadership at the primary school level. Grounded in a critical paradigm, this qualitative research draws upon Kurt Lewin's field theory and theory of change, using participatory action research (PAR) to promote transformation. The research followed a two-phase design. In phase 1, data was collected through individual interviews with teachers and focus group discussions with learners. Phase 2 adopted PAR to assess how engaging learners in the research process stimulated democratic participation and leadership development. Data were gathered through reflective journals maintained by both the learners and the researcher. Abductive analysis of the data, informed by Lewin’s theoretical framework, the Lundy model of participation, Hart’s ladder of participation and leadership theory, revealed varying understandings of democratic participation among participants. For many, it was equated with learners' freedom of expression, collective decision making and leadership autonomy. However, while learners were afforded opportunities to lead school-initiated activities such as cleaning campaigns, sports events and class monitoring, their involvement in the initiation of these activities remained limited. The study found that learner leadership could be significantly enhanced through greater involvement in collective decision making, motivation and recognition by teachers, and increased leadership autonomy. Nonetheless, barriers such as age differences, peer pressure, limited time and teachers’ negative attitudes impeded the realisation of these objectives. The study contributes significant insights into learner leadership in Africa, particularly in the under-researched context of senior primary school leadership. It highlights the need for greater equity in leadership opportunities between primary and secondary learners and advocates a transformative school environment that fosters multiple leadership pathways based on individual cognitive development.Thesis (MEd) -- Faculty of Education, Secondary and Post School Education, 202
Macroinvertebrate colonisation of macroplastic litter in minimally disturbed river sites, Eastern Cape, South Africa
Full text linkMacroplastic pollution remains a growing global environmental concern, and our understanding of its interaction with aquatic organisms is underdeveloped. It is also less clear how hydraulic biotopes influence macroinvertebrates colonisation of macroplastic relative to natural substrates. We investigated temporal and spatial patterns of macroinvertebrate colonisation on macroplastic litters in contrasting stream hydraulic biotopes (riffle, pool, and run) in minimally impacted headwater streams of Eastern Cape, South Africa. Plastic substrates of different proportions of natural and plastic litter were deployed across four sites. The Substrate group included 100% natural substrates (NS), 50% natural material and 50% plastic litters (NP), and 100% plastic (PD) litters. Each substrate group was deployed in riffle, pool, and run habitats for six months at each site