In-betweenness: a postcolonial exploration of sociocultural intergenerational learning through cattle as a medium of cultural expression in Mpembeni, KwaZulu-Natal
- Authors: Masuku, Lynette Sibongile
- Date: 2019
- Subjects: Postcolonialism , Environmental education -- South Africa , Community education -- South Africa -- KwaZulu Natal , Non-formal education -- South Africa -- KwaZulu Natal , Agricultural education -- South Africa -- KwaZulu Natal , Livestock -- Handling -- South Africa -- KwaZulu Natal , Cattle -- Handling -- South Africa -- KwaZulu Natal , Cattle herding -- South Africa -- KwaZulu Natal , Life skills -- Study and teaching -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/68181 , vital:29213
- Description: This case study was conducted in a small rural community called Mpembeni, in South Africa’s KwaZulu-Natal province. It was motivated by my observation of high levels of competence in ‘cattle knowledge’ amongst children coupled with a simultaneous failure at school. I view schools as integral parts of the community and consider them as being influenced by the community, which they in turn influence. This study set out to understand that which embodied informal learning in home/pasture-based contexts as well as formalised learning processes in schools. I used Sociocultural theory as the most congruent of educational theories to surface and illuminate the intergenerational learning processes that were taking place in the area. This warranted my use of research investigation methods that could, in non-intrusive ways, expose the everyday community practices that related to cattle as a particular medium of cultural expression. Ethnography, sourced from anthropology, aided by ethnomethods, was not only compatible with my study and the way in which I wanted to write out the research report, but also with my educational theory and its counterhegemonic intents. To understand the colonialities that framed the discord that embodied home and school as learning contexts, I used postcolonial theory, not only as a lens but as a counterhegemonic response. This theory also informed my research methodology as well as afforded me the reflexivity tools for an examination of my own intergenerational learning and the relational identities of myself as ‘Other’ in the lives of the research participants. It further facilitated the exploration of the potential for potential hybrid third spaces within the bubbling meeting nodes of the socio-cultural context of school and home/pasture based settings of learning. I observed cattle herding related practices, interviewed children, their parents and/or carers, dipping tank managers, livestock inspectors, community elders and members. I also analysed some of the written and unwritten content that made up the formal and informal based learning processes and reviewed some of the most recent South African Curriculum Statements and related texts on the representations of cattle. I sought views from teachers on their interactions with the people of Mpembeni, whose children they taught. I also explored axes of tension, silences and presences on anything related to cattle in schools. I argue and make a case for the development of thought by African scholars to advance Africa’s education rather than aid mimicry and the importation of theories of little congruence and relevance to the African context and Africa’s future. The study has made some contributions to new knowledge. This is in its exploration of sociocultural intergenerational methods and techniques that are employed for learning in community contexts, highlighting the importance of surfacing and understanding of children’s knowledge and experiences. The study has gone further to deliberate the in-betweenness of school and home learning environments, highlighting and unsilencing silenced, peripherised, new, old, considered irrelevant in the past, context and time congruent and liberatory knowledges. I propose that the knowledges located in these cleavages of difference be utilised to transform and create learning bridges between home and school environments. I propose that those ways of knowing that see others as nothings, be exposed and unlearned. Methods of learning that naturally unfold at home could be replicated at school with a recognition of the intergenerational methods, techniques, practices and the learning values in a critically constructive manner that narrows difference and othering.
- Full Text:
- Date Issued: 2019
- Authors: Masuku, Lynette Sibongile
- Date: 2019
- Subjects: Postcolonialism , Environmental education -- South Africa , Community education -- South Africa -- KwaZulu Natal , Non-formal education -- South Africa -- KwaZulu Natal , Agricultural education -- South Africa -- KwaZulu Natal , Livestock -- Handling -- South Africa -- KwaZulu Natal , Cattle -- Handling -- South Africa -- KwaZulu Natal , Cattle herding -- South Africa -- KwaZulu Natal , Life skills -- Study and teaching -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/68181 , vital:29213
- Description: This case study was conducted in a small rural community called Mpembeni, in South Africa’s KwaZulu-Natal province. It was motivated by my observation of high levels of competence in ‘cattle knowledge’ amongst children coupled with a simultaneous failure at school. I view schools as integral parts of the community and consider them as being influenced by the community, which they in turn influence. This study set out to understand that which embodied informal learning in home/pasture-based contexts as well as formalised learning processes in schools. I used Sociocultural theory as the most congruent of educational theories to surface and illuminate the intergenerational learning processes that were taking place in the area. This warranted my use of research investigation methods that could, in non-intrusive ways, expose the everyday community practices that related to cattle as a particular medium of cultural expression. Ethnography, sourced from anthropology, aided by ethnomethods, was not only compatible with my study and the way in which I wanted to write out the research report, but also with my educational theory and its counterhegemonic intents. To understand the colonialities that framed the discord that embodied home and school as learning contexts, I used postcolonial theory, not only as a lens but as a counterhegemonic response. This theory also informed my research methodology as well as afforded me the reflexivity tools for an examination of my own intergenerational learning and the relational identities of myself as ‘Other’ in the lives of the research participants. It further facilitated the exploration of the potential for potential hybrid third spaces within the bubbling meeting nodes of the socio-cultural context of school and home/pasture based settings of learning. I observed cattle herding related practices, interviewed children, their parents and/or carers, dipping tank managers, livestock inspectors, community elders and members. I also analysed some of the written and unwritten content that made up the formal and informal based learning processes and reviewed some of the most recent South African Curriculum Statements and related texts on the representations of cattle. I sought views from teachers on their interactions with the people of Mpembeni, whose children they taught. I also explored axes of tension, silences and presences on anything related to cattle in schools. I argue and make a case for the development of thought by African scholars to advance Africa’s education rather than aid mimicry and the importation of theories of little congruence and relevance to the African context and Africa’s future. The study has made some contributions to new knowledge. This is in its exploration of sociocultural intergenerational methods and techniques that are employed for learning in community contexts, highlighting the importance of surfacing and understanding of children’s knowledge and experiences. The study has gone further to deliberate the in-betweenness of school and home learning environments, highlighting and unsilencing silenced, peripherised, new, old, considered irrelevant in the past, context and time congruent and liberatory knowledges. I propose that the knowledges located in these cleavages of difference be utilised to transform and create learning bridges between home and school environments. I propose that those ways of knowing that see others as nothings, be exposed and unlearned. Methods of learning that naturally unfold at home could be replicated at school with a recognition of the intergenerational methods, techniques, practices and the learning values in a critically constructive manner that narrows difference and othering.
- Full Text:
- Date Issued: 2019
Perspectives on land and water politics at Mushandike Irrigation Scheme, Masvingo, Zimbabwe
- Authors: Mafukidze, Jonathan
- Date: 2019
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/76479 , vital:30573
- Description: Access to, control and ownership of land and water, amongst other natural resources in Zimbabwe, shape and affect rural lives, livelihoods, social relations and social organisation. Rural poverty has been entrenched and exacerbated by, amongst other factors, highly restricted access to these scarce resources. Historically, Zimbabwe’s rural areas (such as communal areas, smallholder irrigation schemes and resettlement areas) have existed as sites of struggles where contestations and negotiations over access to, control or ownership of these resources have taken place. Resultantly, multifaceted and dynamic social relations have been weaved and contested social spaces carved out. In rural Zimbabwe, contestations have tended to be complex, nuanced and intricate, working themselves out in different ways across time and space. In their heightened and more visible state, they have been characterised by violent physical expressions which, in the history of the country, involved two wars of liberation, the First Chimurenga (1896-1897) and the Second Chimurenga (1960s to 1980). The most recent violent manifestation was through nation-wide land invasions, politically christened the Third Chimurenga, which peaked in 2000 and continued sporadically to this day. Few studies on smallholder irrigation schemes in Zimbabwe have focused on understanding how contestations for access to scarce land and water resources are framed and negotiated at the local level. Cognisant of this lacuna, this thesis uses social constructionism in examining, as a case study, Mushandike Smallholder Irrigation Scheme in Masvingo Province in order to understand and analyse how land and water politics occur at the local level. The study deploys a qualitative research methodology approach in examining local water and land politics, which involved original irrigation beneficiaries and more recent land invaders. Findings of the thesis indicate that land and water shortages have increased considerably in the past two decades at the irrigation scheme due to the influx of land invaders into the scheme. This influx has had a negative impact on agricultural production and other livelihood strategies. Both scheme members and land invaders lay claim to land and water at Mushandike. These claims are intricately constructed and contested, and they are linked to broader issues such as partisan party-politics, policy developments, and tradition, origin, indigeneity and belonging. Though the struggles over land and water at Mushandike are firmly rooted in the concrete conditions of existence and experiences of beneficiaries and land invaders, external actors such as political leaders, state bureaucrats and traditional chiefs tend to complicate and intensify the contestations.
- Full Text:
- Date Issued: 2019
- Authors: Mafukidze, Jonathan
- Date: 2019
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/76479 , vital:30573
- Description: Access to, control and ownership of land and water, amongst other natural resources in Zimbabwe, shape and affect rural lives, livelihoods, social relations and social organisation. Rural poverty has been entrenched and exacerbated by, amongst other factors, highly restricted access to these scarce resources. Historically, Zimbabwe’s rural areas (such as communal areas, smallholder irrigation schemes and resettlement areas) have existed as sites of struggles where contestations and negotiations over access to, control or ownership of these resources have taken place. Resultantly, multifaceted and dynamic social relations have been weaved and contested social spaces carved out. In rural Zimbabwe, contestations have tended to be complex, nuanced and intricate, working themselves out in different ways across time and space. In their heightened and more visible state, they have been characterised by violent physical expressions which, in the history of the country, involved two wars of liberation, the First Chimurenga (1896-1897) and the Second Chimurenga (1960s to 1980). The most recent violent manifestation was through nation-wide land invasions, politically christened the Third Chimurenga, which peaked in 2000 and continued sporadically to this day. Few studies on smallholder irrigation schemes in Zimbabwe have focused on understanding how contestations for access to scarce land and water resources are framed and negotiated at the local level. Cognisant of this lacuna, this thesis uses social constructionism in examining, as a case study, Mushandike Smallholder Irrigation Scheme in Masvingo Province in order to understand and analyse how land and water politics occur at the local level. The study deploys a qualitative research methodology approach in examining local water and land politics, which involved original irrigation beneficiaries and more recent land invaders. Findings of the thesis indicate that land and water shortages have increased considerably in the past two decades at the irrigation scheme due to the influx of land invaders into the scheme. This influx has had a negative impact on agricultural production and other livelihood strategies. Both scheme members and land invaders lay claim to land and water at Mushandike. These claims are intricately constructed and contested, and they are linked to broader issues such as partisan party-politics, policy developments, and tradition, origin, indigeneity and belonging. Though the struggles over land and water at Mushandike are firmly rooted in the concrete conditions of existence and experiences of beneficiaries and land invaders, external actors such as political leaders, state bureaucrats and traditional chiefs tend to complicate and intensify the contestations.
- Full Text:
- Date Issued: 2019
Intersectionality and complexity in the representation of ‘queer’ sexualities and genders in African women’s short fiction
- Authors: Du Preez, Jenny Boźena
- Date: 2019
- Subjects: Sexual minority culture , Sexual minorities' writings , African fiction -- Women authors -- History and criticism , Gender identity in literature , Short stories, South African , Feminism in literature , Political poetry , Eroticism in literature , Lesbianism in literature
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/119047 , vital:34697
- Description: This thesis sets out to contribute to the growing body of knowledge about queer sexualities and genders in Africa by examining their depiction in selected post-2000 African women’s short fiction written in English. Post-2000, the short story form has become the primary vehicle for queer representations by African women writers, and is thus an important development in the burgeoning body of queer literature by African writers. Broadly speaking, this literary formation can be defined as anti-homophobic, feminist and politically pragmatic. Using an intersectional lens, this thesis sets out to examine four significant strands in the political work these stories engage in. The chapters are structured around four main points of contention that have particular significance at the intersection of ‘queer’, ‘women’ and ‘Africa’. Firstly, I examine South African short stories that perform what I call queer conversations with history: imaginatively asserting a queer South African history, writing back against a male-dominated and heterosexist literary canon and, in doing so, contributing to the reimagination of the contemporary South African nation. Secondly, I analyse short stories from Africa that foreground the family, both as social formation and ideology. I examine how these stories ‘fracture’ this powerful and naturalised heterosexist concept by depicting the tensions and contradictions that queer characters experience in relation to family. Thirdly, I consider short stories from various African contexts that work to reconceptualise queer sexuality in relation to religious discourse in order to challenge homophobic and patriarchal religious authority. Finally, I examine queer, feminist erotic short stories by African women writers that challenges various colonialist, racist, sexist and lesbophobic discourses that have historically stifled the portrayal of sex and erotic experience between women.
- Full Text:
- Date Issued: 2019
- Authors: Du Preez, Jenny Boźena
- Date: 2019
- Subjects: Sexual minority culture , Sexual minorities' writings , African fiction -- Women authors -- History and criticism , Gender identity in literature , Short stories, South African , Feminism in literature , Political poetry , Eroticism in literature , Lesbianism in literature
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/119047 , vital:34697
- Description: This thesis sets out to contribute to the growing body of knowledge about queer sexualities and genders in Africa by examining their depiction in selected post-2000 African women’s short fiction written in English. Post-2000, the short story form has become the primary vehicle for queer representations by African women writers, and is thus an important development in the burgeoning body of queer literature by African writers. Broadly speaking, this literary formation can be defined as anti-homophobic, feminist and politically pragmatic. Using an intersectional lens, this thesis sets out to examine four significant strands in the political work these stories engage in. The chapters are structured around four main points of contention that have particular significance at the intersection of ‘queer’, ‘women’ and ‘Africa’. Firstly, I examine South African short stories that perform what I call queer conversations with history: imaginatively asserting a queer South African history, writing back against a male-dominated and heterosexist literary canon and, in doing so, contributing to the reimagination of the contemporary South African nation. Secondly, I analyse short stories from Africa that foreground the family, both as social formation and ideology. I examine how these stories ‘fracture’ this powerful and naturalised heterosexist concept by depicting the tensions and contradictions that queer characters experience in relation to family. Thirdly, I consider short stories from various African contexts that work to reconceptualise queer sexuality in relation to religious discourse in order to challenge homophobic and patriarchal religious authority. Finally, I examine queer, feminist erotic short stories by African women writers that challenges various colonialist, racist, sexist and lesbophobic discourses that have historically stifled the portrayal of sex and erotic experience between women.
- Full Text:
- Date Issued: 2019
Pyramidal deliberative democracy
- Authors: Danielsen, James
- Date: 2019
- Subjects: Democracy , Information technology -- Political aspects , Internet in public administration , Political participation -- Computer network resources , World politics
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/74502 , vital:30309
- Description: This dissertation has two main objectives. First, to outline an ICT-facilitated model of democracy called ‘pyramidal democracy’ that reconciles deliberative democracy with mass engagement. Second, to suggest how this model of democracy might engender the democratisation of the global economy and thus the provision of a basic level of economic security for all global citizens. At the core of the model is the pyramidal deliberative network, a means of organising citizens into small online deliberative groups and linking these groups together by means of an iterative process of delegate-selection and group-formation. The pyramidal network enables citizens to aggregate their preferences in a deliberative manner, and then project social power by authorizing the delegates at the top-tier of the pyramidal network to communicate their social demands to elected officials or to other points of authority. The envisioned outcome is the democratisation of the public sphere by means of the proliferation of deliberative networks in the government, market, and civil society spheres. Transnational pyramidal networks may make it feasible to instantiate a new citizen-based schema of global governance and, thereby, facilitate the reform of the United Nations and enable a transition towards global peace, sustainability, and distributive justice. Distributive justice might be achieved by means of implementing the six components of a democratised economy: participatory budgeting, fee-and-dividend taxes, a basic income, monetary reform, workplace democracy, and the sharing economy. Taken together, these components might enable the universal provision of a social minimum – a universal basic income sufficient for basic security and real freedom. Taken to its logical conclusion, a democratised economy may also enable a transition towards a post-scarcity economic order characterised by a maximal stock of humanmade and natural capital that would not exceed the sustainable carrying capacity of the earth.
- Full Text:
- Date Issued: 2019
- Authors: Danielsen, James
- Date: 2019
- Subjects: Democracy , Information technology -- Political aspects , Internet in public administration , Political participation -- Computer network resources , World politics
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/74502 , vital:30309
- Description: This dissertation has two main objectives. First, to outline an ICT-facilitated model of democracy called ‘pyramidal democracy’ that reconciles deliberative democracy with mass engagement. Second, to suggest how this model of democracy might engender the democratisation of the global economy and thus the provision of a basic level of economic security for all global citizens. At the core of the model is the pyramidal deliberative network, a means of organising citizens into small online deliberative groups and linking these groups together by means of an iterative process of delegate-selection and group-formation. The pyramidal network enables citizens to aggregate their preferences in a deliberative manner, and then project social power by authorizing the delegates at the top-tier of the pyramidal network to communicate their social demands to elected officials or to other points of authority. The envisioned outcome is the democratisation of the public sphere by means of the proliferation of deliberative networks in the government, market, and civil society spheres. Transnational pyramidal networks may make it feasible to instantiate a new citizen-based schema of global governance and, thereby, facilitate the reform of the United Nations and enable a transition towards global peace, sustainability, and distributive justice. Distributive justice might be achieved by means of implementing the six components of a democratised economy: participatory budgeting, fee-and-dividend taxes, a basic income, monetary reform, workplace democracy, and the sharing economy. Taken together, these components might enable the universal provision of a social minimum – a universal basic income sufficient for basic security and real freedom. Taken to its logical conclusion, a democratised economy may also enable a transition towards a post-scarcity economic order characterised by a maximal stock of humanmade and natural capital that would not exceed the sustainable carrying capacity of the earth.
- Full Text:
- Date Issued: 2019
A critical realist exploration of the culture of resistance in educational technology integration practices at a South African university
- Authors: Tshuma, Nompilo
- Date: 2019
- Subjects: Critical realism , Educational technology -- South Africa , Education, Higher -- Effect of technological innovations on -- South Africa , College teachers -- South Africa , College teaching -- Sociological aspects -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/72318 , vital:30033
- Description: This thesis seeks to address a number of troubling concerns related to research and practice in the field of educational technology in South African higher education. Firstly, educational technology research has been criticised for a lack of theoretical rigour resulting in perspectives that are tightly focused mostly on practice but fail to adequately interrogate the socio-political complexities of integrating educational technology. Secondly, while research in the field has been criticised for failing to adequately contextualise the study of educational technology, it also fails to interrogate the impact of colonial legacies and Western-developed technologies on integration practices. Thirdly, there seems to be a disconnect between academics’ practices and choices with educational technology, and the expectations and assumptions of educational technologists. As such, this thesis predominantly follows inductive reasoning where literature and theory are applied to the empirical situation retrospectively in order to avoid the potential influences and biases of mostly Western-driven discourses on educational technology integration practices. Critical realism is used to ‘underlabour’ this study. This meta-theory asserts that there are multiple perspectives of an independent reality, and the work of research is to use these perspectives to draw closer to an understanding of that reality. As such, it allows me to interrogate my perspectives firstly, and secondly those of my research participants, about factors that constrain educational technology integration in the South African context through the use of theory (abstract concepts) and data (research participants’ multiple perspectives). However, critical realism is somewhat cautious in how to access this reality. Therefore, a critical ethnographic epistemology is employed to strengthen critical realism’s aim of accessing knowledge. A critical epistemology emphasises exposing hidden power structures, value judgements as well as self-knowledge and reflexivity. The thesis thus shows how a critical realist ontology could be complemented by a critical ethnographic methodology, particularly in critically-orientated research that has an emancipatory focus which seeks to uncover the socio-political context within which educational technology practices take place. A key argument is that critical realism can be employed as an ontological underlabourer for critical research because of: 1) its immanent critique of traditionally-accepted philosophies, 2) its emphasis on critique of our knowledge claims and value judgements, 3) its insistence that knowledge of the social world necessarily precedes emancipation, and 4) its different conceptions of power (oppressive power and transformatory power). This critical ethnographic research is conducted in a South African university with eight female academics. Data collection is in the form of interviews, observations and reflections, as well as informal and work-related interactions. At each data collection moment, I have had to be reflexively aware of my positionality as an educational technologist, the impact of a colonially-motivated methodology and an ethically-aware approach that seeks to put the needs of the research participants first. Critical ethnography’s meaning-making and critical realism’s abduction and retroduction are used to analyse and make sense of the data. In my attempt to contextualise the study’s findings, I first uncover structural forces and their impact on the academic role before attempting to correlate this with educational technology practices. The study’s findings point to two main structural forces in the socio-political context of South African higher education: the teaching/research tension and the elevation of one dominant culture. In terms of the teaching/research tension, the female academics in this study have to balance the urgent teaching function with the valued research function. They struggle to find this balance because of ambiguous messages from different structures, their passion for teaching, oppressive departmental dynamics and the pressures of their career trajectory. The elevation of one dominant culture is demonstrated through both oppressive cultural practices and untransformed curricula. The study shows that academics mitigate these structural constraints mostly through subtle every day resistance that seeks to mitigate their effect on both the academics and, where applicable, their students. Archer’s morphogenetic/morphostatic cycle is used retrospectively, in response to fieldwork, to conceptualise why this resistance comes about. A resistance framework developed using Archer is then used to understand educational technology choices and practices. The results of the research show that while academics are often pictured as resistant to technology as a response to different barriers, they actually often employ technology to resist structural forces. That is, with this thesis I show that there is a focus on resistance with technology rather than resistance to technology. The study shows how the research participants resist structural forces (teaching tension and dominant culture) by using technology to create safe and responsive learning spaces. As such, this thesis challenges educational technologists to re-think the way they support academics by recommending support strategies that acknowledge both the structural forces in the South African higher education context, as well as the culture of resistance, both of which impact academics’ educational technology choices and practices.
- Full Text:
- Date Issued: 2019
- Authors: Tshuma, Nompilo
- Date: 2019
- Subjects: Critical realism , Educational technology -- South Africa , Education, Higher -- Effect of technological innovations on -- South Africa , College teachers -- South Africa , College teaching -- Sociological aspects -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/72318 , vital:30033
- Description: This thesis seeks to address a number of troubling concerns related to research and practice in the field of educational technology in South African higher education. Firstly, educational technology research has been criticised for a lack of theoretical rigour resulting in perspectives that are tightly focused mostly on practice but fail to adequately interrogate the socio-political complexities of integrating educational technology. Secondly, while research in the field has been criticised for failing to adequately contextualise the study of educational technology, it also fails to interrogate the impact of colonial legacies and Western-developed technologies on integration practices. Thirdly, there seems to be a disconnect between academics’ practices and choices with educational technology, and the expectations and assumptions of educational technologists. As such, this thesis predominantly follows inductive reasoning where literature and theory are applied to the empirical situation retrospectively in order to avoid the potential influences and biases of mostly Western-driven discourses on educational technology integration practices. Critical realism is used to ‘underlabour’ this study. This meta-theory asserts that there are multiple perspectives of an independent reality, and the work of research is to use these perspectives to draw closer to an understanding of that reality. As such, it allows me to interrogate my perspectives firstly, and secondly those of my research participants, about factors that constrain educational technology integration in the South African context through the use of theory (abstract concepts) and data (research participants’ multiple perspectives). However, critical realism is somewhat cautious in how to access this reality. Therefore, a critical ethnographic epistemology is employed to strengthen critical realism’s aim of accessing knowledge. A critical epistemology emphasises exposing hidden power structures, value judgements as well as self-knowledge and reflexivity. The thesis thus shows how a critical realist ontology could be complemented by a critical ethnographic methodology, particularly in critically-orientated research that has an emancipatory focus which seeks to uncover the socio-political context within which educational technology practices take place. A key argument is that critical realism can be employed as an ontological underlabourer for critical research because of: 1) its immanent critique of traditionally-accepted philosophies, 2) its emphasis on critique of our knowledge claims and value judgements, 3) its insistence that knowledge of the social world necessarily precedes emancipation, and 4) its different conceptions of power (oppressive power and transformatory power). This critical ethnographic research is conducted in a South African university with eight female academics. Data collection is in the form of interviews, observations and reflections, as well as informal and work-related interactions. At each data collection moment, I have had to be reflexively aware of my positionality as an educational technologist, the impact of a colonially-motivated methodology and an ethically-aware approach that seeks to put the needs of the research participants first. Critical ethnography’s meaning-making and critical realism’s abduction and retroduction are used to analyse and make sense of the data. In my attempt to contextualise the study’s findings, I first uncover structural forces and their impact on the academic role before attempting to correlate this with educational technology practices. The study’s findings point to two main structural forces in the socio-political context of South African higher education: the teaching/research tension and the elevation of one dominant culture. In terms of the teaching/research tension, the female academics in this study have to balance the urgent teaching function with the valued research function. They struggle to find this balance because of ambiguous messages from different structures, their passion for teaching, oppressive departmental dynamics and the pressures of their career trajectory. The elevation of one dominant culture is demonstrated through both oppressive cultural practices and untransformed curricula. The study shows that academics mitigate these structural constraints mostly through subtle every day resistance that seeks to mitigate their effect on both the academics and, where applicable, their students. Archer’s morphogenetic/morphostatic cycle is used retrospectively, in response to fieldwork, to conceptualise why this resistance comes about. A resistance framework developed using Archer is then used to understand educational technology choices and practices. The results of the research show that while academics are often pictured as resistant to technology as a response to different barriers, they actually often employ technology to resist structural forces. That is, with this thesis I show that there is a focus on resistance with technology rather than resistance to technology. The study shows how the research participants resist structural forces (teaching tension and dominant culture) by using technology to create safe and responsive learning spaces. As such, this thesis challenges educational technologists to re-think the way they support academics by recommending support strategies that acknowledge both the structural forces in the South African higher education context, as well as the culture of resistance, both of which impact academics’ educational technology choices and practices.
- Full Text:
- Date Issued: 2019
Using a multi-method approach to understand the movement patterns and the associated environmental correlates of an iconic West African recreational fish
- Authors: Winkler, Alexander Claus
- Date: 2019
- Subjects: Carangidae fishing , Carangidae -- Migration , Carangidae -- Namibia , Carangidae -- Angola , Fish tagging , Carangidae -- Benguela Current , Underwater acoustic telemetry , Ocean temperature -- Physiological effect , Fishes -- Effect of temperature on
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/76530 , vital:30597
- Description: The leerfish (Lichia amia), is a large, primarily coastal recreational fish species with a distribution extending from Portugal down the west coast of African to southern Mozambique. Owing to its large size (30 kg), strong fighting abilities and habit of taking surface artificial lures, this species has taken on an iconic stature among shore-based recreational anglers. Its reputation has made it an important angling tourism species that makes an important contribution to the economy of developing countries. For example, the species brought US$243 per harvested kilogramme into the local southern Angola economy. Despite its high value, little is known about its movement patterns in the northern Benguela coastal region, a region which includes southern Angola and northern Namibia. While much is known about the migratory patterns of the South African stock of L. amia, recent molecular studies have shown that the northern Benguela stock of L. amia has been isolated from the South African population for at least two million years, a consequence of the development of the cold Lüderitz upwelling cell in southern Namibia. Although the global population of L. amia is considered a single species, prominent biogeographic barriers within its distribution and subtle morphological differences between specimens captured within its tropical versus warm-temperate distribution suggest otherwise. A multi-method approach incorporating passive acoustic telemetry (PAT), recreational catch-per-unit-effort (CPUE) and conventional tagging (CT) in southern Angola, as well as recreational fisher-ecological knowledge (FEK) from Namibia, was used to investigate the large-scale movement patterns of L. amia within the northern Benguela coastal region. While each method had its own associated limitations, the combination provided a holistic picture of the population's seasonal migratory patterns. Furthermore, PAT successfully identified partial migration with 25% vs 75% of monitored fish exhibiting resident (movements < 100 km) or migratory (movements > 100 km) behaviour, respectively. Further behavioural diversity was observed with ‘resident’, ‘roaming’ and ‘embayment’ contingents identified based on varying levels of affinity to certain habitats. The presence of both resident and migratory individuals within the northernmost study during June and July, combined with available biological information, suggested that area-specific spawning may take place. While PAT, CPUE and CT largely aligned in determining area specific high-area use, results from network analyses and mixed effects models conducted on the PAT data supported the spawning hypothesis, with anomalous behaviour around specific receivers during the spawning season. All fish, regardless of behavioural contingent, displayed similar movement behaviour during the spawning season and this was driven by factors generally associated with reproduction, such as lunar illumination. Interestingly, these drivers were different from those that determined the area specific use of individuals outside of the spawning season. The environmental drivers of longshore migration into the northern study site were identified as a decline in water temperature and shorter day lengths. The results of this study highlight the importance of using a multi-method approach in determining migratory movement behaviour, area specific area use, and stock structure of key fisheries species. The identification of different behavioural contingents highlights the importance of acknowledging individual variation in movement and habitat-use patterns. This is particularly relevant as future climate change and spatiotemporal variation in fishing effort may artificially skew natural selection processes to favour certain behavioural groups. This study also highlighted the importance of scientists forming relationships with resource-users, such as recreational angling lodges in areas where limited research has been conducted. This is particularly relevant within the West African context where little is known about many of the fish species that are being increasingly targeted by tourism angling ventures.
- Full Text:
- Date Issued: 2019
- Authors: Winkler, Alexander Claus
- Date: 2019
- Subjects: Carangidae fishing , Carangidae -- Migration , Carangidae -- Namibia , Carangidae -- Angola , Fish tagging , Carangidae -- Benguela Current , Underwater acoustic telemetry , Ocean temperature -- Physiological effect , Fishes -- Effect of temperature on
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/76530 , vital:30597
- Description: The leerfish (Lichia amia), is a large, primarily coastal recreational fish species with a distribution extending from Portugal down the west coast of African to southern Mozambique. Owing to its large size (30 kg), strong fighting abilities and habit of taking surface artificial lures, this species has taken on an iconic stature among shore-based recreational anglers. Its reputation has made it an important angling tourism species that makes an important contribution to the economy of developing countries. For example, the species brought US$243 per harvested kilogramme into the local southern Angola economy. Despite its high value, little is known about its movement patterns in the northern Benguela coastal region, a region which includes southern Angola and northern Namibia. While much is known about the migratory patterns of the South African stock of L. amia, recent molecular studies have shown that the northern Benguela stock of L. amia has been isolated from the South African population for at least two million years, a consequence of the development of the cold Lüderitz upwelling cell in southern Namibia. Although the global population of L. amia is considered a single species, prominent biogeographic barriers within its distribution and subtle morphological differences between specimens captured within its tropical versus warm-temperate distribution suggest otherwise. A multi-method approach incorporating passive acoustic telemetry (PAT), recreational catch-per-unit-effort (CPUE) and conventional tagging (CT) in southern Angola, as well as recreational fisher-ecological knowledge (FEK) from Namibia, was used to investigate the large-scale movement patterns of L. amia within the northern Benguela coastal region. While each method had its own associated limitations, the combination provided a holistic picture of the population's seasonal migratory patterns. Furthermore, PAT successfully identified partial migration with 25% vs 75% of monitored fish exhibiting resident (movements < 100 km) or migratory (movements > 100 km) behaviour, respectively. Further behavioural diversity was observed with ‘resident’, ‘roaming’ and ‘embayment’ contingents identified based on varying levels of affinity to certain habitats. The presence of both resident and migratory individuals within the northernmost study during June and July, combined with available biological information, suggested that area-specific spawning may take place. While PAT, CPUE and CT largely aligned in determining area specific high-area use, results from network analyses and mixed effects models conducted on the PAT data supported the spawning hypothesis, with anomalous behaviour around specific receivers during the spawning season. All fish, regardless of behavioural contingent, displayed similar movement behaviour during the spawning season and this was driven by factors generally associated with reproduction, such as lunar illumination. Interestingly, these drivers were different from those that determined the area specific use of individuals outside of the spawning season. The environmental drivers of longshore migration into the northern study site were identified as a decline in water temperature and shorter day lengths. The results of this study highlight the importance of using a multi-method approach in determining migratory movement behaviour, area specific area use, and stock structure of key fisheries species. The identification of different behavioural contingents highlights the importance of acknowledging individual variation in movement and habitat-use patterns. This is particularly relevant as future climate change and spatiotemporal variation in fishing effort may artificially skew natural selection processes to favour certain behavioural groups. This study also highlighted the importance of scientists forming relationships with resource-users, such as recreational angling lodges in areas where limited research has been conducted. This is particularly relevant within the West African context where little is known about many of the fish species that are being increasingly targeted by tourism angling ventures.
- Full Text:
- Date Issued: 2019
Towards a norm of compliance in recreational fisheries
- Authors: Bova, Christopher S
- Date: 2019
- Subjects: Fishing -- Management -- South Africa , Fishery law and legislation -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/95909 , vital:31213
- Description: The activity of fishing can be traced back to prehistoric times. However, only in the last century has there been a focus on the management of fisheries. Fishery regulations are tools used by resource managers with the aim of protecting the long-term sustainability of fishery resources. Although there is an overwhelming amount of evidence demonstrating the decline of fisheries, non-compliance with these regulations by fishers continues to manifest, which can exacerbate the negative ecological impacts of fisheries. Popular methods towards the measurement of noncompliance in fisheries derived from previous human dimensions literature may be flawed. Theories on improving compliance behaviour have typically relied on theory, which has at times proved paradoxical. Addressing the issues of non-compliance within a fishery of interest requires measuring the levels of non-compliance within the fishery and determining the relevant sociopsychological drivers behind the non-compliant behaviour. The data collection methods used during these assessments are limited in human dimensions research and are often case and context specific, requiring researchers to identify which approach is most practical for the specific fishery of interest. By identifying relevant behavioural drivers of non-compliance, a more effective approach aimed at improving compliance can be tailored. The recreational marine-based shore fishery (MBSF) in South Africa is not impervious to noncomplaint behaviour. In fact, it has been estimated to have relatively high rates of non-compliance. This high level of non-compliance makes the South African MBSF a unique and optimal context in which to undertake research that aims to formulate a framework towards compliance assessments and that develops a suitable approach for improving compliance rates. Using surveys to obtain compliance data can provide a range of details about violators, however they are susceptible to social desirability bias (SDB). Choosing the best method for controlling SDB required an assessment of existing methods for doing so. In this first part of the study, only fishers who were covertly observed breaking the rules were surveyed, using one of three methods for reducing SDB, to ground-truth the responses. Ground-truthing was done to determine which method would be most effective for a large-scale study within the same fishery. Of the methods used, which include the direct questioning method (DQM), the random response technique (RRT) and the ballot box method (BBM), all contained some level of SDB. However, the BBM provided a significantly higher level of response accuracy (79.6% ± 11.9) than the DQM (46.5% ± 14.9) and the RRT (44.3% ± 12.5). Random-stratified roving creel compliance surveys that employed the BBM were then undertaken at various locations along South Africa’s coastline to estimate current rates of non-compliance, and the face-to-face results were compared to results from an identical online survey to determine the suitability of online surveys as a replacement. The results indicated that online surveys only represent a subgroup of the fisher population within the MBSF, suggesting that face-to-face survey methods are required to obtain a more comprehensive sample and a more robust estimate of noncompliance. The results, based on 453 face-to-face surveys, showed a high level of overall self-reported noncompliance (48.3%) within the fishery. Responses to Likert scale survey questions on various aspects of the fishery, including angler motivations for fishing, were then modelled to test the relationship between the anglers’ responses and their compliance behaviour. In the South African MBSF context, the most significant behavioural drivers behind non-compliance related to normative concepts. Specifically, the poor perceptions of management and value-based legitimacy as well as low levels of moral obligation to adhere to the regulations appeared to contribute most to the observed non-compliant behaviour. Angler motivations for fishing also played a significant role in determining the compliance behaviour of anglers, with those fishing for food being more likely to violate regulations. In most countries, regardless of economic context, interventions to improve recreational fishery compliance have been developed around the instrumental concept. However, these findings suggest that for recreational fisheries, managers would do well to evaluate the impact of normative concepts on compliance and to design interventions aimed at addressing these. In the case of the South African MBSF, interventions that address angler perceptions of legitimacy and aim to correct misperceptions about social norms of compliance may provide a more practical and cost- effective method for improving poor compliance behaviour.
- Full Text:
- Date Issued: 2019
- Authors: Bova, Christopher S
- Date: 2019
- Subjects: Fishing -- Management -- South Africa , Fishery law and legislation -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/95909 , vital:31213
- Description: The activity of fishing can be traced back to prehistoric times. However, only in the last century has there been a focus on the management of fisheries. Fishery regulations are tools used by resource managers with the aim of protecting the long-term sustainability of fishery resources. Although there is an overwhelming amount of evidence demonstrating the decline of fisheries, non-compliance with these regulations by fishers continues to manifest, which can exacerbate the negative ecological impacts of fisheries. Popular methods towards the measurement of noncompliance in fisheries derived from previous human dimensions literature may be flawed. Theories on improving compliance behaviour have typically relied on theory, which has at times proved paradoxical. Addressing the issues of non-compliance within a fishery of interest requires measuring the levels of non-compliance within the fishery and determining the relevant sociopsychological drivers behind the non-compliant behaviour. The data collection methods used during these assessments are limited in human dimensions research and are often case and context specific, requiring researchers to identify which approach is most practical for the specific fishery of interest. By identifying relevant behavioural drivers of non-compliance, a more effective approach aimed at improving compliance can be tailored. The recreational marine-based shore fishery (MBSF) in South Africa is not impervious to noncomplaint behaviour. In fact, it has been estimated to have relatively high rates of non-compliance. This high level of non-compliance makes the South African MBSF a unique and optimal context in which to undertake research that aims to formulate a framework towards compliance assessments and that develops a suitable approach for improving compliance rates. Using surveys to obtain compliance data can provide a range of details about violators, however they are susceptible to social desirability bias (SDB). Choosing the best method for controlling SDB required an assessment of existing methods for doing so. In this first part of the study, only fishers who were covertly observed breaking the rules were surveyed, using one of three methods for reducing SDB, to ground-truth the responses. Ground-truthing was done to determine which method would be most effective for a large-scale study within the same fishery. Of the methods used, which include the direct questioning method (DQM), the random response technique (RRT) and the ballot box method (BBM), all contained some level of SDB. However, the BBM provided a significantly higher level of response accuracy (79.6% ± 11.9) than the DQM (46.5% ± 14.9) and the RRT (44.3% ± 12.5). Random-stratified roving creel compliance surveys that employed the BBM were then undertaken at various locations along South Africa’s coastline to estimate current rates of non-compliance, and the face-to-face results were compared to results from an identical online survey to determine the suitability of online surveys as a replacement. The results indicated that online surveys only represent a subgroup of the fisher population within the MBSF, suggesting that face-to-face survey methods are required to obtain a more comprehensive sample and a more robust estimate of noncompliance. The results, based on 453 face-to-face surveys, showed a high level of overall self-reported noncompliance (48.3%) within the fishery. Responses to Likert scale survey questions on various aspects of the fishery, including angler motivations for fishing, were then modelled to test the relationship between the anglers’ responses and their compliance behaviour. In the South African MBSF context, the most significant behavioural drivers behind non-compliance related to normative concepts. Specifically, the poor perceptions of management and value-based legitimacy as well as low levels of moral obligation to adhere to the regulations appeared to contribute most to the observed non-compliant behaviour. Angler motivations for fishing also played a significant role in determining the compliance behaviour of anglers, with those fishing for food being more likely to violate regulations. In most countries, regardless of economic context, interventions to improve recreational fishery compliance have been developed around the instrumental concept. However, these findings suggest that for recreational fisheries, managers would do well to evaluate the impact of normative concepts on compliance and to design interventions aimed at addressing these. In the case of the South African MBSF, interventions that address angler perceptions of legitimacy and aim to correct misperceptions about social norms of compliance may provide a more practical and cost- effective method for improving poor compliance behaviour.
- Full Text:
- Date Issued: 2019
Nonlinear optical responses of targeted phthalocyanines when conjugated with nanomaterials or fabricated into polymer thin films
- Authors: Nwaji, Njemuwa Njoku
- Date: 2019
- Subjects: Electrochemistry , Phthalocyanines , Nanoparticles , Bioconjugates , Thin films , Polymers , Nonlinear optics , Nonlinear optical spectroscopy , Nanostructured materials , Raman effect
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/71625 , vital:29926
- Description: A number of zinc, gallium and indium metallophthalocyanines (MPcs) with diverse substituents have been synthesized and characterized using various characterization tools such as proton nuclear magnetic resonance (1HNMR), matrix assisted laser desorption time of flight (MALDI-TOF) mass spectrometry, Fourier-transformed infra-red (FT-IR), Ultraviolet-visible (Uv-vis) spectrophotometry, magnetic circular dichroism and CHNS elemental analysis. The time dependent density functional theory was employed to probe the origin of spectroscopic information in these complexes. Complexes with gallium and indium as central metal showed higher triplet quantum yield compared to the zinc derivatives. Some of the MPcs were covalently linked to nanomaterials such as CdTe, CdTeSe, CdTeSe/ZnO, graphene quantum dots (GQDs) as well as metallic gold (AuNPs) and silver (AgNPs) nanoparticles. Others were either surface assembled onto AuNPs and AgNPs or embedded into polystyrene as polymer source. The phthalocyanine-nanomaterial composites (Pc-NMCs) were characterized with FT-IR, UV-visible spectrophotometry, transmission electron microscopy (TEM), dynamic light scattering (DLS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffractometry (XRD). The thickness of the thin films was determined by utilization of the knife edge attachment of the A Bruker D8 Discover X-ray diffraction. The optical limiting properties (using the open-aperture Z-scan technique) of the MPcs and the Pc-NMCs were investigated. The investigated MPcs complexes generally showed good optical limiting properties. The nonlinear optical response of the MPcs were improved in the presence of nanomaterials such as the semiconductor quantum dots (SQDs), graphene quantum dots (GQDs) as well as metallic AuNPs and AgNPs with MPc-QDs showing the best optical limiting behavior. The optical limiting properties of the MPcs were greatly enhanced in the presence of polymer thin films.
- Full Text:
- Date Issued: 2019
- Authors: Nwaji, Njemuwa Njoku
- Date: 2019
- Subjects: Electrochemistry , Phthalocyanines , Nanoparticles , Bioconjugates , Thin films , Polymers , Nonlinear optics , Nonlinear optical spectroscopy , Nanostructured materials , Raman effect
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/71625 , vital:29926
- Description: A number of zinc, gallium and indium metallophthalocyanines (MPcs) with diverse substituents have been synthesized and characterized using various characterization tools such as proton nuclear magnetic resonance (1HNMR), matrix assisted laser desorption time of flight (MALDI-TOF) mass spectrometry, Fourier-transformed infra-red (FT-IR), Ultraviolet-visible (Uv-vis) spectrophotometry, magnetic circular dichroism and CHNS elemental analysis. The time dependent density functional theory was employed to probe the origin of spectroscopic information in these complexes. Complexes with gallium and indium as central metal showed higher triplet quantum yield compared to the zinc derivatives. Some of the MPcs were covalently linked to nanomaterials such as CdTe, CdTeSe, CdTeSe/ZnO, graphene quantum dots (GQDs) as well as metallic gold (AuNPs) and silver (AgNPs) nanoparticles. Others were either surface assembled onto AuNPs and AgNPs or embedded into polystyrene as polymer source. The phthalocyanine-nanomaterial composites (Pc-NMCs) were characterized with FT-IR, UV-visible spectrophotometry, transmission electron microscopy (TEM), dynamic light scattering (DLS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffractometry (XRD). The thickness of the thin films was determined by utilization of the knife edge attachment of the A Bruker D8 Discover X-ray diffraction. The optical limiting properties (using the open-aperture Z-scan technique) of the MPcs and the Pc-NMCs were investigated. The investigated MPcs complexes generally showed good optical limiting properties. The nonlinear optical response of the MPcs were improved in the presence of nanomaterials such as the semiconductor quantum dots (SQDs), graphene quantum dots (GQDs) as well as metallic AuNPs and AgNPs with MPc-QDs showing the best optical limiting behavior. The optical limiting properties of the MPcs were greatly enhanced in the presence of polymer thin films.
- Full Text:
- Date Issued: 2019
Application of computational methods in elucidating the isomerization step in the biosynthesis of coumarins
- Authors: Tshiwawa, Tendamudzimu
- Date: 2019
- Subjects: Coumarins , Isomerization , Biosynthesis , Organic compounds -- Synthesis , Cinnamic acid
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/67646 , vital:29124
- Description: The identity of the enzyme(s) responsible for the biosynthetic transformation of cinnamic acid derivatives to important, naturally occurring coumarins has yet to be established. This study constitutes a high-level theoretical analysis of the possibility that a recently reported molecular mechanism of the synthesis of coumarins from Baylis-Hillman adducts, may provide a viable model for three critical phases in the biosynthetic pathway Particular attention has been given to the first of these phases: i) E→Z isomerisation of the cinnamic acid precursor; ii) Cyclisation (lactonisation) to the hemi-acetal intermediate; and ii) Dehydration to afford the coumarin derivative. In order to accomplish this analysis, an enzyme capable, theoretically, of effecting this E→Z isomerisation required identification, and its potential involvement in the transformation mechanism explored. Combined Molecular Mechanics and high-level Quantum Mechanical/DFT calculations were used to access complementary models of appropriate complexes and relevant processes within the enzyme active sites of a range of eleven Chalcone Isomerase (CHI) enzyme candidates, the structures of which were downloaded from the Protein Data Bank. Detailed B3LYP/6-31+G(d,p) calculations have provided pictures of the relative populations of conformations within the ensemble of conformations available at normal temperatures. Conformations of several protonation states of cinnamic acid derivatives have been studied in this way, and the results obtained showed that coupled protonation and deprotonation of (E)-o-coumaric acid provides a viable approach to achieve the E→Z isomerization. In silico docking of the B3LYP/6-31+G(d,p) optimized (E)-o-coumaric acid derivatives in the active sites of each of the candidate CHI enzymes (CHI) revealed that (E)-o-coumaric acid fits well within the active sites of Medicago Sativa CHI crystallographic structures with 1FM8 showing best potential for not only accommodating (E)-o-coumaric acid , but also providing appropriate protein active site residues to effect the simultaneous protonation and deprotonation of the substrate , two residues being optimally placed to facilitate these critical processes. Further exploration of the chemical properties and qualities of selected CHI enzymes, undertaken using High Throughput Virtual Screening (HTVS), confirmed 1FM8 as a viable choice for further studies of the enzyme-catalysed E→Z isomerization of (E)-o-coumaric acid. A molecular dynamics study, performed to further evaluate the evolution of (E)-o-coumaric acid in the CHI active site over time, showed that the ligand in the 1FM8 active site is not only stable, but also that the desired protein-ligand interactions persist throughout the simulation period to facilitate the E→Z isomerization. An integrated molecular orbital and molecular mechanics (ONIOM) study of the 1FM8-(E)-o-coumaric acid complex, involving the direct protonation and deprotonation of the ligand by protein residues; has provided a plausible mechanism for the E → Z isomerization of (E)-o-coumaric acid within the 1FM8 active site; a transition state complex (with an activation energy of ca. 50 kCal.mol-1) has been located and its connection with both the (E)- and (Z)-o-coumaric acid isomer has been confirmed by Intrinsic Reaction Coordinate (IRC) calculations. More realistic models of the 1FM8-(E)-o-coumaric acid complex, with the inclusion of water solvent molecules, have been obtained at both the QM/MM and adaptive QM/MM levels which simulate the dynamic active site at the QM level. The results indicate that the simultaneous protonation and deprotonation of (E)-o-coumaric acid within the CHI enzyme is a water-mediated process – a conclusion consistent with similar reported processes. Visual inspection of the 1FM8-(Z)-o-coumaric acid complex reveals both the necessary orientation of the phenolic and carboxylic acid moieties of the (Z)-o-coumaric acid and the presence of appropriate, proximal active site residues with the potential to permit catalysis of the subsequent lactonisation and dehydration steps required to generate coumarin.
- Full Text:
- Date Issued: 2019
- Authors: Tshiwawa, Tendamudzimu
- Date: 2019
- Subjects: Coumarins , Isomerization , Biosynthesis , Organic compounds -- Synthesis , Cinnamic acid
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/67646 , vital:29124
- Description: The identity of the enzyme(s) responsible for the biosynthetic transformation of cinnamic acid derivatives to important, naturally occurring coumarins has yet to be established. This study constitutes a high-level theoretical analysis of the possibility that a recently reported molecular mechanism of the synthesis of coumarins from Baylis-Hillman adducts, may provide a viable model for three critical phases in the biosynthetic pathway Particular attention has been given to the first of these phases: i) E→Z isomerisation of the cinnamic acid precursor; ii) Cyclisation (lactonisation) to the hemi-acetal intermediate; and ii) Dehydration to afford the coumarin derivative. In order to accomplish this analysis, an enzyme capable, theoretically, of effecting this E→Z isomerisation required identification, and its potential involvement in the transformation mechanism explored. Combined Molecular Mechanics and high-level Quantum Mechanical/DFT calculations were used to access complementary models of appropriate complexes and relevant processes within the enzyme active sites of a range of eleven Chalcone Isomerase (CHI) enzyme candidates, the structures of which were downloaded from the Protein Data Bank. Detailed B3LYP/6-31+G(d,p) calculations have provided pictures of the relative populations of conformations within the ensemble of conformations available at normal temperatures. Conformations of several protonation states of cinnamic acid derivatives have been studied in this way, and the results obtained showed that coupled protonation and deprotonation of (E)-o-coumaric acid provides a viable approach to achieve the E→Z isomerization. In silico docking of the B3LYP/6-31+G(d,p) optimized (E)-o-coumaric acid derivatives in the active sites of each of the candidate CHI enzymes (CHI) revealed that (E)-o-coumaric acid fits well within the active sites of Medicago Sativa CHI crystallographic structures with 1FM8 showing best potential for not only accommodating (E)-o-coumaric acid , but also providing appropriate protein active site residues to effect the simultaneous protonation and deprotonation of the substrate , two residues being optimally placed to facilitate these critical processes. Further exploration of the chemical properties and qualities of selected CHI enzymes, undertaken using High Throughput Virtual Screening (HTVS), confirmed 1FM8 as a viable choice for further studies of the enzyme-catalysed E→Z isomerization of (E)-o-coumaric acid. A molecular dynamics study, performed to further evaluate the evolution of (E)-o-coumaric acid in the CHI active site over time, showed that the ligand in the 1FM8 active site is not only stable, but also that the desired protein-ligand interactions persist throughout the simulation period to facilitate the E→Z isomerization. An integrated molecular orbital and molecular mechanics (ONIOM) study of the 1FM8-(E)-o-coumaric acid complex, involving the direct protonation and deprotonation of the ligand by protein residues; has provided a plausible mechanism for the E → Z isomerization of (E)-o-coumaric acid within the 1FM8 active site; a transition state complex (with an activation energy of ca. 50 kCal.mol-1) has been located and its connection with both the (E)- and (Z)-o-coumaric acid isomer has been confirmed by Intrinsic Reaction Coordinate (IRC) calculations. More realistic models of the 1FM8-(E)-o-coumaric acid complex, with the inclusion of water solvent molecules, have been obtained at both the QM/MM and adaptive QM/MM levels which simulate the dynamic active site at the QM level. The results indicate that the simultaneous protonation and deprotonation of (E)-o-coumaric acid within the CHI enzyme is a water-mediated process – a conclusion consistent with similar reported processes. Visual inspection of the 1FM8-(Z)-o-coumaric acid complex reveals both the necessary orientation of the phenolic and carboxylic acid moieties of the (Z)-o-coumaric acid and the presence of appropriate, proximal active site residues with the potential to permit catalysis of the subsequent lactonisation and dehydration steps required to generate coumarin.
- Full Text:
- Date Issued: 2019
The impact of policies on development-induced resettlement processes and outcomes: a Lesotho-India comparative study
- Tsietsi, Teboho Priscilla Mosuoe
- Authors: Tsietsi, Teboho Priscilla Mosuoe
- Date: 2019
- Subjects: Forced migration -- Lesotho , Forced migration -- India , Dams -- Social aspects -- Lesotho , Dams -- Social aspects -- India , Irrigation projects -- Economic aspects -- Lesotho , Irrigation projects -- Economic aspects -- India , Land settlement -- Government policy -- Lesotho , Land settlement -- Government policy -- India
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/72307 , vital:30032
- Description: The practice of Development-Induced Displacement and Resettlement (DIDR), historically, has often led to negative consequences for those affected by development projects, including but not limited to, the construction of large dams. Although DIDR arises from the need to provide goods and services that characterise development, it often leaves those who are forced to give up their assets, resources, and long standing social networks in dire socio-economic conditions as a result of resettlement. In many such cases, the provision for losses suffered by those primarily affected is often insufficient, leading to further losses experienced as a result of the complete life change experienced by those affected by resettlement. Research has shown that the insufficiency of such provisions for losses is attributable to not only the value of the provision itself, but also the manner in which resettlement processes are implemented. While early on, researchers believed that the development of policies would have a significant, positive impact on the practice of resettlement and its outcomes, evidence would later show that the development of policies alone is not a panacea for all challenges associated with forced resettlement. Further research revealed that resettlement is characterised by inherent and active complexities which are often at play, and may impede effective implementation. Hence, while the development of policies is essential, both the development and implementation of policies must be undertaken in a manner that seeks to actively address the inherent complexities of resettlement. This thesis aims to explore the implementation of resettlement policies in two case studies, where in one case, resettlement was informed by national policy, and in the other, by policies developed by a parastatal tasked with the responsibility of executing resettlement. The study makes a comparative analysis between the two cases, and explores the factors at play in the implementation of resettlement policies – whether such factors serve to facilitate or impede effective implementation – as well as the nature of the outcomes on the ground. As an overarching goal, the research aims to provide a basis upon which a framework for the development of a national level policy of resettlement may be developed. In this regard, the thesis undertakes a comparison of the Indian resettlement case with the Lesotho case. The former, in addition to having developed a resettlement policy at the national level, has a long history of experience in forced resettlement and displacement, from which invaluable lessons have been learned. The latter, on the other hand, has no resettlement policy at the national level, although the country has also experienced forced resettlement dating back to nearly three decades ago. Although India and Lesotho have distinct social, cultural, economic and demographic characteristics, research has shown that the complexities of forced resettlement, and their outcomes on affected people, are largely applicable across the different contexts. Hence, certain dimensions and lessons can be transferable from the Indian case to the Lesotho case, and vice versa. However, for the purpose of this thesis, the focus is on providing a basis for national policy development in Lesotho, in light of Indian policies and practice. The empirical basis of the thesis is an ethnographic study undertaken in relation to the Chandil Dam resettlement case in Jharkhand, India and the Mohale Dam resettlement case in Maseru, Lesotho. The thesis engaged both qualitative and quantitative research methods, as well as four, complementary theoretical tools that analyse the effects of forced resettlement on affected people. The thesis reveals that the negative consequences of forced resettlement resulting from its inherent complexities continue to manifest with concerning effects on the lives of those affected. It shows that the implementation of policies is a complex process that requires collaborative effort from a wide range of stakeholders in a given context. National policies of resettlement are, thus, instrumental in this regard, as they can create an enabling environment for the facilitation of collaborative efforts towards sustainable livelihood re-establishment for those who involuntarily suffer losses to resettlement.
- Full Text:
- Date Issued: 2019
- Authors: Tsietsi, Teboho Priscilla Mosuoe
- Date: 2019
- Subjects: Forced migration -- Lesotho , Forced migration -- India , Dams -- Social aspects -- Lesotho , Dams -- Social aspects -- India , Irrigation projects -- Economic aspects -- Lesotho , Irrigation projects -- Economic aspects -- India , Land settlement -- Government policy -- Lesotho , Land settlement -- Government policy -- India
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/72307 , vital:30032
- Description: The practice of Development-Induced Displacement and Resettlement (DIDR), historically, has often led to negative consequences for those affected by development projects, including but not limited to, the construction of large dams. Although DIDR arises from the need to provide goods and services that characterise development, it often leaves those who are forced to give up their assets, resources, and long standing social networks in dire socio-economic conditions as a result of resettlement. In many such cases, the provision for losses suffered by those primarily affected is often insufficient, leading to further losses experienced as a result of the complete life change experienced by those affected by resettlement. Research has shown that the insufficiency of such provisions for losses is attributable to not only the value of the provision itself, but also the manner in which resettlement processes are implemented. While early on, researchers believed that the development of policies would have a significant, positive impact on the practice of resettlement and its outcomes, evidence would later show that the development of policies alone is not a panacea for all challenges associated with forced resettlement. Further research revealed that resettlement is characterised by inherent and active complexities which are often at play, and may impede effective implementation. Hence, while the development of policies is essential, both the development and implementation of policies must be undertaken in a manner that seeks to actively address the inherent complexities of resettlement. This thesis aims to explore the implementation of resettlement policies in two case studies, where in one case, resettlement was informed by national policy, and in the other, by policies developed by a parastatal tasked with the responsibility of executing resettlement. The study makes a comparative analysis between the two cases, and explores the factors at play in the implementation of resettlement policies – whether such factors serve to facilitate or impede effective implementation – as well as the nature of the outcomes on the ground. As an overarching goal, the research aims to provide a basis upon which a framework for the development of a national level policy of resettlement may be developed. In this regard, the thesis undertakes a comparison of the Indian resettlement case with the Lesotho case. The former, in addition to having developed a resettlement policy at the national level, has a long history of experience in forced resettlement and displacement, from which invaluable lessons have been learned. The latter, on the other hand, has no resettlement policy at the national level, although the country has also experienced forced resettlement dating back to nearly three decades ago. Although India and Lesotho have distinct social, cultural, economic and demographic characteristics, research has shown that the complexities of forced resettlement, and their outcomes on affected people, are largely applicable across the different contexts. Hence, certain dimensions and lessons can be transferable from the Indian case to the Lesotho case, and vice versa. However, for the purpose of this thesis, the focus is on providing a basis for national policy development in Lesotho, in light of Indian policies and practice. The empirical basis of the thesis is an ethnographic study undertaken in relation to the Chandil Dam resettlement case in Jharkhand, India and the Mohale Dam resettlement case in Maseru, Lesotho. The thesis engaged both qualitative and quantitative research methods, as well as four, complementary theoretical tools that analyse the effects of forced resettlement on affected people. The thesis reveals that the negative consequences of forced resettlement resulting from its inherent complexities continue to manifest with concerning effects on the lives of those affected. It shows that the implementation of policies is a complex process that requires collaborative effort from a wide range of stakeholders in a given context. National policies of resettlement are, thus, instrumental in this regard, as they can create an enabling environment for the facilitation of collaborative efforts towards sustainable livelihood re-establishment for those who involuntarily suffer losses to resettlement.
- Full Text:
- Date Issued: 2019
Stakeholder relationship management of a Chinese Mining Organisation in Zimbabwe
- Authors: Chodokufa, Kudakwashe
- Date: 2019
- Subjects: Industrial management -- Zimbabwe , Mineral industries -- Zimbabwe -- Management , Investments, Chinese -- Zimbabwe
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/115127 , vital:34080
- Description: Media reports and research has pointed out problems in the way that Chinese mining organisations in Zimbabwe are managing stakeholder relationships. The problems ranging from disgruntled communities and allegations of labour violations. Taking into account the impact that China’s FDI has had on the ailing Zimbabwean economy research into the management of stakeholder relationships becomes imperative to understand how Chinese mining organisations build and manage stakeholder relationships. A review of stakeholder theory has revealed that there is not much emphasis by researchers on how organisations manage their stakeholder relationships, but rather on the identification and analysis of stakeholders. Research that has focused on stakeholder relationships has focused on different elements found in stakeholder relationship management and not necessarily on how stakeholder relationships should be managed. On the other hand, stakeholder theory does not seem to include social licence to operate which is important in stakeholder relationship management within the mining context. The purpose of this study is to develop a multidimensional stakeholder relationship management process for the Chinese mining organisation in Zimbabwe, showing dynamic interactions between multiple stakeholder networks with complementary, competitive and/or cooperative interests, while taking into account the possibility that interests may vary according to the underlying context. Thirteen semi-structured in-depth interviews were conducted with three stakeholder groups of a Chinese mining organisation as identified from the literature, namely employees, government and the community. The critical incident technique (CIT) was adopted in developing the interview questions and facilitated the data collection process. Participants described 36 critical incidents. According to multiple stakeholders, the findings suggest that, the Chinese managers built the relationship with multiple stakeholders through friendship, negotiation, pretend not to understand, referral, singing a contract, started with problems, they just arrived and through the government. With the same relationship being managed by the Chinese managers by being hard, rough and ruthless, authoritative, Chinese way of doing things, used avoidance, lack of competency, through a third party and resolving conflict when managing stakeholder relationships. Showing that the building and managing of stakeholder relationships is socially constructed and experienced differently by stakeholders. The positive and negative relationship characteristics influenced how stakeholder relationships are managed by the selected Chinese mining organisation. In the presence of positive relationship characteristics which included, friendship,there was flexibility, power dynamics, accountability depends on situations, commitment a show of investment, do cooperate to a certain extent, trust began with an open mind, shared values: hardwork and profit, shared values: culture was associated with the Chinese managing the relationship through being kind, supportive, motivating and understanding; complaint; through a third party; controlling; Chinese way of doing things; and performance and reward management of stakeholder relationships. Whilst negative relationship characteristics which included fear, their hearts were hardened, Chinese had power, intimidaton, not accountable, lack of commitment, communication understanding, connotations and intretations, communication done through a third party; no cooperation want to cut coners; trust are they conveying what is being said; deception and misrepresentation; trust depends on experience; being told lies and not transparent were associated with negative (being authoritative; hard, rough and ruthless; avoidance; blame shifting and pushy) stakeholder relationship management by the Chinese managers. Hence, a proposition that negative or positive relationship characteristics result in negative or positive stakeholder relationship management by the Chinese managers was propossed. The following challenges were experienced in the management of stakeholder relationships namely, communication, corruption, cheating, political environment, working conditions and broken promises. The dynamic multidimensional stakeholder relationship management process was subsequently revised to accommodate the new relationship characteristics and their positive and negative influence on how stakeholder relationships are managed. The main contribution of this study is the dynamic multidimensional stakeholder relationship management process which was developed within the context of a Chinese mining organisation in Africa. It is recommended that practitioners utilise the dynamic multidimensional stakeholder relationship management process to assist them in understanding and conducting research on stakeholder relationships. Further research is suggested on developing the research proposition made in the study and to empirically test the dynamic multidimension stakeholder relationship management process in other industries that posses different or similar contexts as this study.
- Full Text:
- Date Issued: 2019
- Authors: Chodokufa, Kudakwashe
- Date: 2019
- Subjects: Industrial management -- Zimbabwe , Mineral industries -- Zimbabwe -- Management , Investments, Chinese -- Zimbabwe
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/115127 , vital:34080
- Description: Media reports and research has pointed out problems in the way that Chinese mining organisations in Zimbabwe are managing stakeholder relationships. The problems ranging from disgruntled communities and allegations of labour violations. Taking into account the impact that China’s FDI has had on the ailing Zimbabwean economy research into the management of stakeholder relationships becomes imperative to understand how Chinese mining organisations build and manage stakeholder relationships. A review of stakeholder theory has revealed that there is not much emphasis by researchers on how organisations manage their stakeholder relationships, but rather on the identification and analysis of stakeholders. Research that has focused on stakeholder relationships has focused on different elements found in stakeholder relationship management and not necessarily on how stakeholder relationships should be managed. On the other hand, stakeholder theory does not seem to include social licence to operate which is important in stakeholder relationship management within the mining context. The purpose of this study is to develop a multidimensional stakeholder relationship management process for the Chinese mining organisation in Zimbabwe, showing dynamic interactions between multiple stakeholder networks with complementary, competitive and/or cooperative interests, while taking into account the possibility that interests may vary according to the underlying context. Thirteen semi-structured in-depth interviews were conducted with three stakeholder groups of a Chinese mining organisation as identified from the literature, namely employees, government and the community. The critical incident technique (CIT) was adopted in developing the interview questions and facilitated the data collection process. Participants described 36 critical incidents. According to multiple stakeholders, the findings suggest that, the Chinese managers built the relationship with multiple stakeholders through friendship, negotiation, pretend not to understand, referral, singing a contract, started with problems, they just arrived and through the government. With the same relationship being managed by the Chinese managers by being hard, rough and ruthless, authoritative, Chinese way of doing things, used avoidance, lack of competency, through a third party and resolving conflict when managing stakeholder relationships. Showing that the building and managing of stakeholder relationships is socially constructed and experienced differently by stakeholders. The positive and negative relationship characteristics influenced how stakeholder relationships are managed by the selected Chinese mining organisation. In the presence of positive relationship characteristics which included, friendship,there was flexibility, power dynamics, accountability depends on situations, commitment a show of investment, do cooperate to a certain extent, trust began with an open mind, shared values: hardwork and profit, shared values: culture was associated with the Chinese managing the relationship through being kind, supportive, motivating and understanding; complaint; through a third party; controlling; Chinese way of doing things; and performance and reward management of stakeholder relationships. Whilst negative relationship characteristics which included fear, their hearts were hardened, Chinese had power, intimidaton, not accountable, lack of commitment, communication understanding, connotations and intretations, communication done through a third party; no cooperation want to cut coners; trust are they conveying what is being said; deception and misrepresentation; trust depends on experience; being told lies and not transparent were associated with negative (being authoritative; hard, rough and ruthless; avoidance; blame shifting and pushy) stakeholder relationship management by the Chinese managers. Hence, a proposition that negative or positive relationship characteristics result in negative or positive stakeholder relationship management by the Chinese managers was propossed. The following challenges were experienced in the management of stakeholder relationships namely, communication, corruption, cheating, political environment, working conditions and broken promises. The dynamic multidimensional stakeholder relationship management process was subsequently revised to accommodate the new relationship characteristics and their positive and negative influence on how stakeholder relationships are managed. The main contribution of this study is the dynamic multidimensional stakeholder relationship management process which was developed within the context of a Chinese mining organisation in Africa. It is recommended that practitioners utilise the dynamic multidimensional stakeholder relationship management process to assist them in understanding and conducting research on stakeholder relationships. Further research is suggested on developing the research proposition made in the study and to empirically test the dynamic multidimension stakeholder relationship management process in other industries that posses different or similar contexts as this study.
- Full Text:
- Date Issued: 2019
Large scale spatio-temporal forcing of pelagic-coastal coupling: disentangling the effects of environmental change on intertidal invertebrate recruitment
- Authors: Muñiz, Carlota Fernández
- Date: 2019
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/75317 , vital:30400
- Description: Marine systems are driven by the relationships among organisms and environmental conditions. Anthropogenic-induced changes during the past decades have started to alter climatic drivers which have the potential to alter the physical, chemical and biological environment. In coastal systems, biogeography is influenced by the temporal variability in the conditions of the water mass. In addition, many marine benthic organisms develop in the water mass and rely on the conditions that link the pelagic and benthic systems for population maintenance. Such pelagic-coastal coupling indicates that changes in the trophic system during development can be transferred to the adult populations through changes in propagule supply. Thus, changes in environmental conditions can influence benthic populations directly (e.g. through larval advection) or indirectly, through their influence on the phytoplankton community (e.g. through the development of HABs). The South African coastline shows clear alongshore patterns of faunal biomass and species richness. On the south coast, strong longitudinal patterns of recruitment of intertidal organisms exist, with areas of particularly high recruitment. HABs of unprecedented spatio-temporal magnitude have recently developed along the south coast, including the areas where benthic recruitment is most intense. The present thesis used these blooms to study changes in intertidal recruitment directly or indirectly associated with their occurrence. Using a combination of remote sensing data to study the environmental conditions of the water mass in the innermost part of the Agulhas Bank, and estimates of mussel and barnacle recruitment rates to integrate the effects of conditions in the water mass during larval development, this thesis aimed to: (1) understand the conditions that triggered the development of an HAB of the dinoflagellate Lingulodinium polyedrum during summer of 2014, (2) determine the direct or indirect effects of that bloom on recruitment of intertidal organisms, and understand the factors that affect recruitment along the coast, (3) determine if the environmental factors during bloom development produced any carryover effects on recruit growth and mortality, and (4) determine the factors that drive changes in community biomass and composition along the south coast, the long-term trends in those factors, and possible changes experienced in recent years. Water column stability during spring, before the development of the red tide, followed by alternating periods of upwelling and relaxation during summer and autumn, seemed to promote the development and persistence of L. polyedrum. Recruitment of mussels and barnacles was estimated during the reproductive season of mussels in 2014, coinciding with the red tide, and during the following year. Alongshore patterns in recruitment were found, with higher mussel recruitment in the absence of the red tide and the opposite pattern in barnacles. Alongshore patterns in SST and chlorophyll matching those of recruitment were also found, with higher SSTs and lower chlorophyll during the red tide than the following year. Growth and mortality rates in barnacles did not differ between years during the first five months after settlement. This suggests that the factors which produced differences in recruitment between years did not produce carryover effects detectable at the temporal scales studied. Further analysis of 15 years of satellite-derived environmental data showed significant cooling trends potentially driven by a long-term seasonal acceleration of the Agulhas Current in autumn around two upwelling centres on the south coast, coinciding temporally with the reproductive period of mussels and barnacles, and spatially with the areas of highest recruitment. In addition, the comparison of SST and chl-a conditions during the first and the second half of the period of study showed that seasonality of both variables has changed in large areas over the shelf, with increasing importance of shorter-term variability, which would in turn decrease environmental predictability. Thus, the conditions observed during the present study, particularly during 2015, when upwelling seemed to be more intense, may presage the potential effects of identified long-term cooling trends at the upwelling centres. Although the general trend shows cooling around those areas, conditions can vary greatly among years, favouring different taxa. Changes in the Agulhas Current System are affected by changes in distant areas in the Indian Ocean basin. Such tele-connection is unlikely to be unique to this system and indicates the importance of understanding trends in major large scale climatic drivers and their regional effects in order to make predictions about coastal systems.
- Full Text:
- Date Issued: 2019
- Authors: Muñiz, Carlota Fernández
- Date: 2019
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/75317 , vital:30400
- Description: Marine systems are driven by the relationships among organisms and environmental conditions. Anthropogenic-induced changes during the past decades have started to alter climatic drivers which have the potential to alter the physical, chemical and biological environment. In coastal systems, biogeography is influenced by the temporal variability in the conditions of the water mass. In addition, many marine benthic organisms develop in the water mass and rely on the conditions that link the pelagic and benthic systems for population maintenance. Such pelagic-coastal coupling indicates that changes in the trophic system during development can be transferred to the adult populations through changes in propagule supply. Thus, changes in environmental conditions can influence benthic populations directly (e.g. through larval advection) or indirectly, through their influence on the phytoplankton community (e.g. through the development of HABs). The South African coastline shows clear alongshore patterns of faunal biomass and species richness. On the south coast, strong longitudinal patterns of recruitment of intertidal organisms exist, with areas of particularly high recruitment. HABs of unprecedented spatio-temporal magnitude have recently developed along the south coast, including the areas where benthic recruitment is most intense. The present thesis used these blooms to study changes in intertidal recruitment directly or indirectly associated with their occurrence. Using a combination of remote sensing data to study the environmental conditions of the water mass in the innermost part of the Agulhas Bank, and estimates of mussel and barnacle recruitment rates to integrate the effects of conditions in the water mass during larval development, this thesis aimed to: (1) understand the conditions that triggered the development of an HAB of the dinoflagellate Lingulodinium polyedrum during summer of 2014, (2) determine the direct or indirect effects of that bloom on recruitment of intertidal organisms, and understand the factors that affect recruitment along the coast, (3) determine if the environmental factors during bloom development produced any carryover effects on recruit growth and mortality, and (4) determine the factors that drive changes in community biomass and composition along the south coast, the long-term trends in those factors, and possible changes experienced in recent years. Water column stability during spring, before the development of the red tide, followed by alternating periods of upwelling and relaxation during summer and autumn, seemed to promote the development and persistence of L. polyedrum. Recruitment of mussels and barnacles was estimated during the reproductive season of mussels in 2014, coinciding with the red tide, and during the following year. Alongshore patterns in recruitment were found, with higher mussel recruitment in the absence of the red tide and the opposite pattern in barnacles. Alongshore patterns in SST and chlorophyll matching those of recruitment were also found, with higher SSTs and lower chlorophyll during the red tide than the following year. Growth and mortality rates in barnacles did not differ between years during the first five months after settlement. This suggests that the factors which produced differences in recruitment between years did not produce carryover effects detectable at the temporal scales studied. Further analysis of 15 years of satellite-derived environmental data showed significant cooling trends potentially driven by a long-term seasonal acceleration of the Agulhas Current in autumn around two upwelling centres on the south coast, coinciding temporally with the reproductive period of mussels and barnacles, and spatially with the areas of highest recruitment. In addition, the comparison of SST and chl-a conditions during the first and the second half of the period of study showed that seasonality of both variables has changed in large areas over the shelf, with increasing importance of shorter-term variability, which would in turn decrease environmental predictability. Thus, the conditions observed during the present study, particularly during 2015, when upwelling seemed to be more intense, may presage the potential effects of identified long-term cooling trends at the upwelling centres. Although the general trend shows cooling around those areas, conditions can vary greatly among years, favouring different taxa. Changes in the Agulhas Current System are affected by changes in distant areas in the Indian Ocean basin. Such tele-connection is unlikely to be unique to this system and indicates the importance of understanding trends in major large scale climatic drivers and their regional effects in order to make predictions about coastal systems.
- Full Text:
- Date Issued: 2019
Regional thickening as game-changing: examining transnational activities of gender and women-focused civil society actors for region-building in Southern Africa
- Authors: Nedziwe, Cecilia Lwiindi
- Date: 2019
- Subjects: International relations , Southern Africa Development Community , Regionalism -- Africa, Southern , Africa, Southern -- Foreign relations -- 1994- , Women in development -- Africa, Southern , Women -- Social conditions -- Africa, Southern , Women -- Political activity -- Africa, Southern , Women in public life -- Africa, Southern , Civil society -- Africa, Southern
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/95420 , vital:31154
- Description: This thesis argues that norms, in general, have proliferated in a neo-liberalising context since the 1990s, in particular norms on gender, and how they have changed to indicate new agency and influence, amounts to game change. Despite growing transnational activities, regionalisation and the increasing interface between state and non-state regionalism in a transnational context since the advent of liberalisation and democratisation, analyses in regional International Relations (IR) studies, so far, largely maintain linear logic. The increasing non-state processes, and their connection to state processes in norm creation, norm adaptation, norm diffusion and implementation around broad questions of security including in the area of gender, amount to regional thickening. Regional thickening revealed in terms of increasing regionalisation, regionalism, and region-ness whose effect is game-changing challenges mainstream linear approaches in regional IR studies. Game-changing here, refers to, processes promoting the development of norms mentioned above in the interest of contributing to improved security across a region. This study is focused on Southern Africa, defined here, as the Southern African Development Community (SADC) region. This study’s analytical approach is informed by alternatives to mainstream approaches, emphasising processes, rather than linearity inherent in regional IR studies. By privileging the actual game-changing processes, interactions, and agency around the norm development cycle, this study examines how regional thickening in a transnational context promotes game-changing activities, promoting the development of the norm cycle, seeking to have improved security. A mixed method approach involving gathering of information from multiple primary and secondary sources are used. The study found transnational activities and regionalisation of gender and women-focused civil society actors, game-changing. These civil society actors organised in two ways. First, by way of advocacy and in seeking representation within intergovernmental policymaking structures at a regional level. Second, by way of organising around transnational communities in a transnational context in the interest of addressing gendered insecurities at localised levels. Regional thickening as game-changing here pointed to a growing recognition and participation of civil society actors in intergovernmental policymaking spaces as having created a groundswell for game change at localised levels. This led to policy development, adaptation, diffusion, and implementation by both state and non-state actors contributing to norm changes, improved social policies, and to greater security. The actual changes emerging from these actors’ activities on the ground are in terms of unlearning patriarchal behaviours, opening up development for women, and increasing their living standards, education, health, and their freedom. In assessing the transnational environment on gendered insecurity in Southern Africa, this thesis developed an innovative framework of regional thickening as game-changing. This framework plots how game-changing developed, evolved, and its importance in addressing gendered insecurity. The thesis has proposed that game-changing transnational activities and regionalisation that change, and diffuse norms to break learnt behaviour, have helped disrupt rigid institutionalisation, and are aiding to bring non-linear discourses to the fore.
- Full Text:
- Date Issued: 2019
- Authors: Nedziwe, Cecilia Lwiindi
- Date: 2019
- Subjects: International relations , Southern Africa Development Community , Regionalism -- Africa, Southern , Africa, Southern -- Foreign relations -- 1994- , Women in development -- Africa, Southern , Women -- Social conditions -- Africa, Southern , Women -- Political activity -- Africa, Southern , Women in public life -- Africa, Southern , Civil society -- Africa, Southern
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/95420 , vital:31154
- Description: This thesis argues that norms, in general, have proliferated in a neo-liberalising context since the 1990s, in particular norms on gender, and how they have changed to indicate new agency and influence, amounts to game change. Despite growing transnational activities, regionalisation and the increasing interface between state and non-state regionalism in a transnational context since the advent of liberalisation and democratisation, analyses in regional International Relations (IR) studies, so far, largely maintain linear logic. The increasing non-state processes, and their connection to state processes in norm creation, norm adaptation, norm diffusion and implementation around broad questions of security including in the area of gender, amount to regional thickening. Regional thickening revealed in terms of increasing regionalisation, regionalism, and region-ness whose effect is game-changing challenges mainstream linear approaches in regional IR studies. Game-changing here, refers to, processes promoting the development of norms mentioned above in the interest of contributing to improved security across a region. This study is focused on Southern Africa, defined here, as the Southern African Development Community (SADC) region. This study’s analytical approach is informed by alternatives to mainstream approaches, emphasising processes, rather than linearity inherent in regional IR studies. By privileging the actual game-changing processes, interactions, and agency around the norm development cycle, this study examines how regional thickening in a transnational context promotes game-changing activities, promoting the development of the norm cycle, seeking to have improved security. A mixed method approach involving gathering of information from multiple primary and secondary sources are used. The study found transnational activities and regionalisation of gender and women-focused civil society actors, game-changing. These civil society actors organised in two ways. First, by way of advocacy and in seeking representation within intergovernmental policymaking structures at a regional level. Second, by way of organising around transnational communities in a transnational context in the interest of addressing gendered insecurities at localised levels. Regional thickening as game-changing here pointed to a growing recognition and participation of civil society actors in intergovernmental policymaking spaces as having created a groundswell for game change at localised levels. This led to policy development, adaptation, diffusion, and implementation by both state and non-state actors contributing to norm changes, improved social policies, and to greater security. The actual changes emerging from these actors’ activities on the ground are in terms of unlearning patriarchal behaviours, opening up development for women, and increasing their living standards, education, health, and their freedom. In assessing the transnational environment on gendered insecurity in Southern Africa, this thesis developed an innovative framework of regional thickening as game-changing. This framework plots how game-changing developed, evolved, and its importance in addressing gendered insecurity. The thesis has proposed that game-changing transnational activities and regionalisation that change, and diffuse norms to break learnt behaviour, have helped disrupt rigid institutionalisation, and are aiding to bring non-linear discourses to the fore.
- Full Text:
- Date Issued: 2019
Governing pregnancy in South Africa: political and health debate, policy and procedures
- Authors: Du Plessis, Ulandi
- Date: 2019
- Subjects: South Africa. Department of Health (1994- ) , Maternal health services -- South Africa , Mothers -- Mortality -- South Africa , Prenatal care -- South Africa , African mothers -- Mortality -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/76552 , vital:30600
- Description: South Africa democratised in 1994. However, due to the discriminatory and segregationist character of the preceding regime, vast swathes of the country’s spaces and people entered the democratic period heavily deprived of essential government services. This was the case with health care in general, including maternal health care. There were also little to no national data available on maternal deaths, especially among the black population. One of the first tasks of the new National Department of Health (NDoH) was to target the high maternal mortality rate. The NDoH made maternal deaths notifiable by law and instituted auditing and information gathering systems in the health sector; health infrastructure was expanded exponentially, and maternal health care was made free. Despite this, the last 24 years have seen the maternal mortality escalate. The latest statistics show that between 1200 and 1300 women die in the South African public health sector each year during pregnancy and the puerperium. This puts the current institutional maternal mortality rate (MMR) at around 154/100 000 live births. The international target for ‘developing’ countries was to reduce the MMR rate by three quarters by 2015, which would have meant a reduction to 38/100 000 live births. The aim of this dissertation is to examine how the democratic South African government (influenced heavily by global health thinking) has laboured to reduce that statistic. I analyse, using Foucauldian discourse analysis, all relevant health and maternal health policies, procedural documents and reports produced by and for the NDoH in the last 24 years. I draw on Foucauldian concepts, specifically those related to Foucault’s work on governmentality. In this dissertation I introduce a new perspective towards the maternal health practices implemented in South Africa, practices that have generally remained unquestioned, been perceived as self-evident, and thus often escaping critical analysis. Through an analysis of the intended operation of the public antenatal clinic (within the larger institutional system) I show how ‘development’ has come to operate as a truth regime in South Africa – facilitating the introduction of liberal governmentality (including some advanced liberal practices) into public health service provision.
- Full Text:
- Date Issued: 2019
- Authors: Du Plessis, Ulandi
- Date: 2019
- Subjects: South Africa. Department of Health (1994- ) , Maternal health services -- South Africa , Mothers -- Mortality -- South Africa , Prenatal care -- South Africa , African mothers -- Mortality -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/76552 , vital:30600
- Description: South Africa democratised in 1994. However, due to the discriminatory and segregationist character of the preceding regime, vast swathes of the country’s spaces and people entered the democratic period heavily deprived of essential government services. This was the case with health care in general, including maternal health care. There were also little to no national data available on maternal deaths, especially among the black population. One of the first tasks of the new National Department of Health (NDoH) was to target the high maternal mortality rate. The NDoH made maternal deaths notifiable by law and instituted auditing and information gathering systems in the health sector; health infrastructure was expanded exponentially, and maternal health care was made free. Despite this, the last 24 years have seen the maternal mortality escalate. The latest statistics show that between 1200 and 1300 women die in the South African public health sector each year during pregnancy and the puerperium. This puts the current institutional maternal mortality rate (MMR) at around 154/100 000 live births. The international target for ‘developing’ countries was to reduce the MMR rate by three quarters by 2015, which would have meant a reduction to 38/100 000 live births. The aim of this dissertation is to examine how the democratic South African government (influenced heavily by global health thinking) has laboured to reduce that statistic. I analyse, using Foucauldian discourse analysis, all relevant health and maternal health policies, procedural documents and reports produced by and for the NDoH in the last 24 years. I draw on Foucauldian concepts, specifically those related to Foucault’s work on governmentality. In this dissertation I introduce a new perspective towards the maternal health practices implemented in South Africa, practices that have generally remained unquestioned, been perceived as self-evident, and thus often escaping critical analysis. Through an analysis of the intended operation of the public antenatal clinic (within the larger institutional system) I show how ‘development’ has come to operate as a truth regime in South Africa – facilitating the introduction of liberal governmentality (including some advanced liberal practices) into public health service provision.
- Full Text:
- Date Issued: 2019
The Afropolitan flâneur: literary representations of the city and contemporary urban identities in selected African and transnational texts
- Authors: Leff, Carol Willa
- Date: 2019
- Subjects: City and town life in literature , African literature (English) -- History and criticism , Flaneurs in literature
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/115082 , vital:34076
- Description: When an individual walks the urban landscape there is a unique symbiosis between self and city. It is through walking the cityscape and observing the crowd and the surrounding environment that the archetypal literary figure of the European flâneur acts as a mirror of a particular time and space. But how might such a flâneur walk and observe the city in contemporary African and transnational literary texts? I argue that there is a literary re-imagining and repurposing of the flâneur figure which has hitherto not been acknowledged and explored: an Afropolitan flâneur. ‘Afropolitan’ is a term popularised by Taiye Selasi in a 2005 essay to refer to a ‘scattered tribe’ of ‘Africans of the world’ (n. pag.). In this dissertation, the entanglement of the Afropolitan subject and the European flâneur brings together past and present, Africa and the West. I first provide a historical and theoretical framework to illustrate how the flâneur figure ‘migrated’ from Europe to Africa, and how this figure is to be understood as a literary construct, in relation to current considerations of Afropolitanism. I go on to discuss a wide range of texts that engage with Afropolitan flâneurs who traverse cities in Africa (such as Johannesburg, Cape Town and Lagos), or global north cities (New York, Paris and London). While some of the Afropolitan flâneurs depicted in these texts are migrants or homeless individuals who struggle to adapt easily to a new environment, others, despite being more privileged, also sometimes experience uncomfortable assimilation in their new or strange city space. There are also those who seem to feel equally at home wherever they find themselves. As these Afropolitan flâneurs walk their way through the urban landscape in the texts under examination, they reflect different ways of being in the city. By problematising the binaries of local/global, national/transnational, black/white, slum/paradise, this dissertation seeks to address issues of belonging or not belonging and gestures towards new ways of understanding what it means to be an African in the world.
- Full Text:
- Date Issued: 2019
- Authors: Leff, Carol Willa
- Date: 2019
- Subjects: City and town life in literature , African literature (English) -- History and criticism , Flaneurs in literature
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/115082 , vital:34076
- Description: When an individual walks the urban landscape there is a unique symbiosis between self and city. It is through walking the cityscape and observing the crowd and the surrounding environment that the archetypal literary figure of the European flâneur acts as a mirror of a particular time and space. But how might such a flâneur walk and observe the city in contemporary African and transnational literary texts? I argue that there is a literary re-imagining and repurposing of the flâneur figure which has hitherto not been acknowledged and explored: an Afropolitan flâneur. ‘Afropolitan’ is a term popularised by Taiye Selasi in a 2005 essay to refer to a ‘scattered tribe’ of ‘Africans of the world’ (n. pag.). In this dissertation, the entanglement of the Afropolitan subject and the European flâneur brings together past and present, Africa and the West. I first provide a historical and theoretical framework to illustrate how the flâneur figure ‘migrated’ from Europe to Africa, and how this figure is to be understood as a literary construct, in relation to current considerations of Afropolitanism. I go on to discuss a wide range of texts that engage with Afropolitan flâneurs who traverse cities in Africa (such as Johannesburg, Cape Town and Lagos), or global north cities (New York, Paris and London). While some of the Afropolitan flâneurs depicted in these texts are migrants or homeless individuals who struggle to adapt easily to a new environment, others, despite being more privileged, also sometimes experience uncomfortable assimilation in their new or strange city space. There are also those who seem to feel equally at home wherever they find themselves. As these Afropolitan flâneurs walk their way through the urban landscape in the texts under examination, they reflect different ways of being in the city. By problematising the binaries of local/global, national/transnational, black/white, slum/paradise, this dissertation seeks to address issues of belonging or not belonging and gestures towards new ways of understanding what it means to be an African in the world.
- Full Text:
- Date Issued: 2019
Rural food security in Mutare District, Zimbabwe, 1947-2010
- Authors: Kusena, Bernard
- Date: 2019
- Subjects: Mutare (Zimbabwe) -- History , Zimbabwe -- History , Food security -- Zimbabwe , Poverty -- Zimbabwe , Rural pooer -- Zimbabwe , Crop losses -- Zimbabwe , Food relief -- Zimbabwe
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/92865 , vital:30757
- Description: By taking Mutare District as its lens to explore the dynamics of rural food security in Zimbabwe, this thesis assesses the role of the state in tackling hunger among its rural populations. It examines the impact of colonial and post-colonial food policy on efforts to combat food insecurity. The thesis explores the uneasy options pursued by rural communities in response to droughts and other threats of hunger. It identifies and ranks crop failure as the chief culprit to the district’s efforts towards food security. The thesis illustrates the contestations between the state and its rural people over which sustainable approaches to adopt in order to end hunger and how such debates continually shaped policy. It grapples with questions about the various understandings of food security advanced by scholars within the rural African context. It demonstrates, for instance, that the post-colonial state inherited an erstwhile crop production structure which shunned food crops in favour of cash crops. There was obvious bias against local preferences for a robust, home-grown food regime which did not put rural livelihoods at risk of starvation. The thesis also argues that food can be used as an instrument of war as evidenced during the liberation struggle when the vast majority of people residing in rural areas, particularly women and children, were pushed to the edges of survival. In addition, the thesis demonstrates that the infamous Marange diamonds turned out to be a curse rather than a blessing due to the state’s lack of transparency in the beneficiation chain. It concludes by a detailed examination of the political economy of food aid, demonstrating why donors have not succeeded for long to combat hunger in the district. In light of this background, the thesis provides a more nuanced analysis of the whole question of rural food security using archival material, newspapers, government and civil society reports, interviews and field observation. The thesis benefits from the use of a multi-pronged theoretical framework to capture the disparate themes that form the bedrock of this study.
- Full Text:
- Date Issued: 2019
- Authors: Kusena, Bernard
- Date: 2019
- Subjects: Mutare (Zimbabwe) -- History , Zimbabwe -- History , Food security -- Zimbabwe , Poverty -- Zimbabwe , Rural pooer -- Zimbabwe , Crop losses -- Zimbabwe , Food relief -- Zimbabwe
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/92865 , vital:30757
- Description: By taking Mutare District as its lens to explore the dynamics of rural food security in Zimbabwe, this thesis assesses the role of the state in tackling hunger among its rural populations. It examines the impact of colonial and post-colonial food policy on efforts to combat food insecurity. The thesis explores the uneasy options pursued by rural communities in response to droughts and other threats of hunger. It identifies and ranks crop failure as the chief culprit to the district’s efforts towards food security. The thesis illustrates the contestations between the state and its rural people over which sustainable approaches to adopt in order to end hunger and how such debates continually shaped policy. It grapples with questions about the various understandings of food security advanced by scholars within the rural African context. It demonstrates, for instance, that the post-colonial state inherited an erstwhile crop production structure which shunned food crops in favour of cash crops. There was obvious bias against local preferences for a robust, home-grown food regime which did not put rural livelihoods at risk of starvation. The thesis also argues that food can be used as an instrument of war as evidenced during the liberation struggle when the vast majority of people residing in rural areas, particularly women and children, were pushed to the edges of survival. In addition, the thesis demonstrates that the infamous Marange diamonds turned out to be a curse rather than a blessing due to the state’s lack of transparency in the beneficiation chain. It concludes by a detailed examination of the political economy of food aid, demonstrating why donors have not succeeded for long to combat hunger in the district. In light of this background, the thesis provides a more nuanced analysis of the whole question of rural food security using archival material, newspapers, government and civil society reports, interviews and field observation. The thesis benefits from the use of a multi-pronged theoretical framework to capture the disparate themes that form the bedrock of this study.
- Full Text:
- Date Issued: 2019
Investigating and expanding learning across activity system boundaries in improved cook stove innovation diffusion and adoption in Malawi
- Jalasi, Experencia Madalitso
- Authors: Jalasi, Experencia Madalitso
- Date: 2019
- Subjects: Stoves, Wood -- Technological innovations -- Malawi , Biomass stoves -- Malawi , Economic development projects -- Environmental aspects -- Malawi , Rural development projects -- Environmental aspects -- Malawi
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/68170 , vital:29212
- Description: This study investigates and expands learning within and between activity systems working with Improved Cook Stoves (hereafter ICS) in Malawi. The study focuses on how existing learning interactions among ICS actors can be expanded using expansive learning processes, mobilised through Boundary Crossing Change Laboratories (BCCL) to potentially inform more sustained uptake and utilisation of the ICS technology. The ICS, as a socio-technical innovation, seeks to respond to climate change mitigation and adaptation efforts in the country. However, sustained uptake and utilisation has been problematic. The study is located in the field of Environmental Education, with emphasis on the diffusion and adoption of socio-technical innovations in the context of ICS technology. The study addresses societal environmental health risks faced by people using traditional biomass fuels indoors on open fires, commonly referred to as Three Stone Fire (hereafter TSF) through formative intervention supported by Developmental Work Research (hereafter DWR) or Expansive Learning. The study was conducted in three climate change hotspot districts in Malawi: Balaka, Dedza and Mzimba. The case studies are in each of the three administrative regions of the country. Chapita Village case study is in Balaka district, in the Southern region; Waziloya Makwakwa Village is in Mzimba district in the Northern region; and Chilije Village in Dedza district in the Central region. In order to engage the potential for transformation in study areas, I divided the study into two phases. The first phase involved collection of ethnographic data to more deeply understand the context of the problem including existing learning approaches. This informed the second phase, which focused on expansive learning processes in the Chapita and Waziloya Makwakwa case studies. The study used a formative intervention approach, which focused on supporting the actors to manage the challenges they were facing and work out the problematic situations in their joint activity. The study employed a qualitative intensive research design because it aimed at in-depth understanding of uptake and utilisation of ICS. This was an important foundation for improving the existing situations through co-creating solutions with research participants. With this generative and action-oriented approach, the study employed a multiple embedded case study design. CHAT and Critical Realism were the two main theories that I employed as they resonated with the transformative interest of the study through focusing on learning as an emancipatory process with potential for transformation of human practices. In addition, I used the methodological theory of Expansive Learning from CHAT to guide the expansive learning processes. With the critical realist framing of the study, I employed a critical realist analytical framework, and used inductive, abductive and retroductive analyses.The major findings of the study indicate that broadly, uptake and utilisation of ICS is problematic, hence unsustained. The findings indicate that the majority of end-users in Chapita and Chilije case studies switched between TSF and ICS, or abandoned the ICS, which was not the case in Waziloya Makwakwa case study. The underlying causal mechanisms that appear to explain and influence end-users’ actions in all the case studies were the search for convenience during the cooking activity. Further, findings revealed that learning interactions among activity systems were unidirectional which provides evidence for top-down approaches prevalent in cook stove dissemination. The findings also indicated that most of the learning taking place was informative, not transformative. It was also inadequate, particularly for end-users. A causal mechanism that appears to shape how actors are learning ICS technology is poverty, which results in over-reliance on donor-driven projects. Findings also reveal that contradictions in the learning, uptake and utilisation of ICS influence the profile of uptake and utilisation of ICSs. Further, the change-oriented learning processes, as carried out in the Chapita and Waziloya Makwakwa case studies, have shown their potential in expanding learning interactions among ICS actors, evoking and supporting their transformative agency and enhancing their reflexivity. These processes are crucial in development and sustaining learning and change in the uptake and utilisation of ICS innovation. The main contribution of the study is methodological. It contributes broadly to diffusion and adoption of socio-technical innovations through change-oriented expansive learning processes. The study generated an Innovative Extension and Communicative Methodology, which foregrounds interaction and learning and links the socio-technical innovation intention and socio-technical innovation uptake and utilisation that potentially informs the dissemination and implementation of ICS projects. Further, the study contributes to community education by mobilising communities to address contradictions, absences, or ills in the society via change-oriented learning processes. The societal ills facing the case study sites and the areas around them, caused by climate change and variability and deforestation exacerbate the lives of rural women who are afflicted by conditions of poverty. The study contributes to global and local efforts and initiatives to address environmental health risks faced by people using traditional biomass fuels indoors on TSF and climate change mitigation and adaptation. This study has found out that putting the agency of the end-user in the centre in socio-technical transitions through context-based problem resolution and rigorous deliberate1 mediated processes of participation and learning, which allows multivoicedness and takes power relations into account, catalyses transformative agency, reflexivity, collaboration and learning capacity of ICS actors for sustained uptake and utilisation of the ICS socio-technical innovation.
- Full Text:
- Date Issued: 2019
- Authors: Jalasi, Experencia Madalitso
- Date: 2019
- Subjects: Stoves, Wood -- Technological innovations -- Malawi , Biomass stoves -- Malawi , Economic development projects -- Environmental aspects -- Malawi , Rural development projects -- Environmental aspects -- Malawi
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/68170 , vital:29212
- Description: This study investigates and expands learning within and between activity systems working with Improved Cook Stoves (hereafter ICS) in Malawi. The study focuses on how existing learning interactions among ICS actors can be expanded using expansive learning processes, mobilised through Boundary Crossing Change Laboratories (BCCL) to potentially inform more sustained uptake and utilisation of the ICS technology. The ICS, as a socio-technical innovation, seeks to respond to climate change mitigation and adaptation efforts in the country. However, sustained uptake and utilisation has been problematic. The study is located in the field of Environmental Education, with emphasis on the diffusion and adoption of socio-technical innovations in the context of ICS technology. The study addresses societal environmental health risks faced by people using traditional biomass fuels indoors on open fires, commonly referred to as Three Stone Fire (hereafter TSF) through formative intervention supported by Developmental Work Research (hereafter DWR) or Expansive Learning. The study was conducted in three climate change hotspot districts in Malawi: Balaka, Dedza and Mzimba. The case studies are in each of the three administrative regions of the country. Chapita Village case study is in Balaka district, in the Southern region; Waziloya Makwakwa Village is in Mzimba district in the Northern region; and Chilije Village in Dedza district in the Central region. In order to engage the potential for transformation in study areas, I divided the study into two phases. The first phase involved collection of ethnographic data to more deeply understand the context of the problem including existing learning approaches. This informed the second phase, which focused on expansive learning processes in the Chapita and Waziloya Makwakwa case studies. The study used a formative intervention approach, which focused on supporting the actors to manage the challenges they were facing and work out the problematic situations in their joint activity. The study employed a qualitative intensive research design because it aimed at in-depth understanding of uptake and utilisation of ICS. This was an important foundation for improving the existing situations through co-creating solutions with research participants. With this generative and action-oriented approach, the study employed a multiple embedded case study design. CHAT and Critical Realism were the two main theories that I employed as they resonated with the transformative interest of the study through focusing on learning as an emancipatory process with potential for transformation of human practices. In addition, I used the methodological theory of Expansive Learning from CHAT to guide the expansive learning processes. With the critical realist framing of the study, I employed a critical realist analytical framework, and used inductive, abductive and retroductive analyses.The major findings of the study indicate that broadly, uptake and utilisation of ICS is problematic, hence unsustained. The findings indicate that the majority of end-users in Chapita and Chilije case studies switched between TSF and ICS, or abandoned the ICS, which was not the case in Waziloya Makwakwa case study. The underlying causal mechanisms that appear to explain and influence end-users’ actions in all the case studies were the search for convenience during the cooking activity. Further, findings revealed that learning interactions among activity systems were unidirectional which provides evidence for top-down approaches prevalent in cook stove dissemination. The findings also indicated that most of the learning taking place was informative, not transformative. It was also inadequate, particularly for end-users. A causal mechanism that appears to shape how actors are learning ICS technology is poverty, which results in over-reliance on donor-driven projects. Findings also reveal that contradictions in the learning, uptake and utilisation of ICS influence the profile of uptake and utilisation of ICSs. Further, the change-oriented learning processes, as carried out in the Chapita and Waziloya Makwakwa case studies, have shown their potential in expanding learning interactions among ICS actors, evoking and supporting their transformative agency and enhancing their reflexivity. These processes are crucial in development and sustaining learning and change in the uptake and utilisation of ICS innovation. The main contribution of the study is methodological. It contributes broadly to diffusion and adoption of socio-technical innovations through change-oriented expansive learning processes. The study generated an Innovative Extension and Communicative Methodology, which foregrounds interaction and learning and links the socio-technical innovation intention and socio-technical innovation uptake and utilisation that potentially informs the dissemination and implementation of ICS projects. Further, the study contributes to community education by mobilising communities to address contradictions, absences, or ills in the society via change-oriented learning processes. The societal ills facing the case study sites and the areas around them, caused by climate change and variability and deforestation exacerbate the lives of rural women who are afflicted by conditions of poverty. The study contributes to global and local efforts and initiatives to address environmental health risks faced by people using traditional biomass fuels indoors on TSF and climate change mitigation and adaptation. This study has found out that putting the agency of the end-user in the centre in socio-technical transitions through context-based problem resolution and rigorous deliberate1 mediated processes of participation and learning, which allows multivoicedness and takes power relations into account, catalyses transformative agency, reflexivity, collaboration and learning capacity of ICS actors for sustained uptake and utilisation of the ICS socio-technical innovation.
- Full Text:
- Date Issued: 2019
Charting freedom: inequality beliefs, preferences for redistribution, and distributive social policy in contemporary South Africa
- Authors: Roberts, Benjamin J
- Date: 2019
- Subjects: South Africa -- Economic conditions South Africa -- Economic policy South Africa -- Social policy , Democracy -- Economic conditions -- South Africa Race discrimination -- South Africa Poverty -- South Africa Equality -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/64999 , vital:28644
- Description: While the transition to democracy in South Africa extended civil and political rights and freedoms to all South Africans, there has been disagreement over the preferred nature and scope of social rights within post-apartheid society, reflecting debates over the trajectory of economic policy. Appreciable developmental gains have been made by the state over the last quarter-century, yet the challenges of poverty, unemployment and inequality persist, coupled with mounting popular discontent with the pace of transformation and political accountability. This has led to fundamental questions about social justice, restitution, and the kind of society we wish to promote. Appeals for a more inclusive, transformative social policy have also emerged, arguing that a wider vision of society is required involving multiple government responsibilities and informed by an ethic of equality and social solidarity. Against this background, in this thesis I study the views of the South African public towards economic inequality, general preferences for government-led redistribution, as well as support for social policies intended to promote racial and economic transformation. The research has been guided by several overarching questions: To what extent do South Africans share common general beliefs about material inequality? Does the public exhibit a preference for government redistribution in principle? And how unified or polarised are South Africans in their support for specific redress policies in the country? Responding to these questions has been achieved by drawing on unique, nationally representative data from the South African Social Attitudes Survey (SASAS), which has enabled me to chart social attitudes over a period of almost fifteen years between late 2003 and early 2017. Use has also been made of social citizenship as a guiding conceptual framework to understanding social policy predispositions and analysing attitudinal change. The results demonstrate that the public is united in its awareness of and deep concern about economic inequality. Since the early 2000s, a significant majority has consistently expressed the view that the income gap in the country is too large, articulated a strong preference for a more equitable social structure, and acknowledged the class and social tensions that economic inequality has produced. There is also a preference for a narrowing of earnings disparities, a more generous minimum wage, and regulatory limits on executive pay. While this suggests a desire for fair and legitimate remuneration, the analysis also reveals that South Africans are willing to tolerate fairly high levels of inequality. Nonetheless, these beliefs are generally interpreted as a desire for a more equitable and fair society. This preference for change is reflected in a fairly strong belief that government should assume responsibility for reducing material disparities. One’s social position, mobility history, awareness of inequality, political leaning and racial attitudes all have a bearing on how weak and strong this predisposition is, but the normative demand for political redistribution remains fairly widely shared irrespective of these individual traits. Greater polarisation is however evident with respect to redistributive social policy, especially measures designed to overcome historical racial injustice (affirmative action, sports quotas, and land reform). These intergroup differences converge considerably when referring to class-based policy measures. One surprising finding is the evidence that South Africa’s youngest generation, the so-called ‘Born Frees’, tend to adopt a similar predisposition to redress policy as older generations, thus confounding expectations of a post-apartheid value change. I conclude by arguing that there seems to be a firmer basis for a social compact about preferences for interventions designed to produce a more just society than is typically assumed. Intractably high levels of economic inequality during the country’s first quarter-century of democracy is resulting in a growing recognition of the need for a stronger policy emphasis on economic inequality in South Africa over coming decades if the vision enshrined in the Freedom Charter and the Constitution is to be realised. South Africans may not be able to fully agree about the specific elements that constitute a socially just response to economic inequality. Yet, the common identification of and concern with redressable injustice, coupled with a broad-based commitment to government redistribution and classbased social policies, could serve as a foundation on which to rekindle the solidaristic spirit of 1994 and forge progress towards a more equitable society.
- Full Text:
- Date Issued: 2019
- Authors: Roberts, Benjamin J
- Date: 2019
- Subjects: South Africa -- Economic conditions South Africa -- Economic policy South Africa -- Social policy , Democracy -- Economic conditions -- South Africa Race discrimination -- South Africa Poverty -- South Africa Equality -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/64999 , vital:28644
- Description: While the transition to democracy in South Africa extended civil and political rights and freedoms to all South Africans, there has been disagreement over the preferred nature and scope of social rights within post-apartheid society, reflecting debates over the trajectory of economic policy. Appreciable developmental gains have been made by the state over the last quarter-century, yet the challenges of poverty, unemployment and inequality persist, coupled with mounting popular discontent with the pace of transformation and political accountability. This has led to fundamental questions about social justice, restitution, and the kind of society we wish to promote. Appeals for a more inclusive, transformative social policy have also emerged, arguing that a wider vision of society is required involving multiple government responsibilities and informed by an ethic of equality and social solidarity. Against this background, in this thesis I study the views of the South African public towards economic inequality, general preferences for government-led redistribution, as well as support for social policies intended to promote racial and economic transformation. The research has been guided by several overarching questions: To what extent do South Africans share common general beliefs about material inequality? Does the public exhibit a preference for government redistribution in principle? And how unified or polarised are South Africans in their support for specific redress policies in the country? Responding to these questions has been achieved by drawing on unique, nationally representative data from the South African Social Attitudes Survey (SASAS), which has enabled me to chart social attitudes over a period of almost fifteen years between late 2003 and early 2017. Use has also been made of social citizenship as a guiding conceptual framework to understanding social policy predispositions and analysing attitudinal change. The results demonstrate that the public is united in its awareness of and deep concern about economic inequality. Since the early 2000s, a significant majority has consistently expressed the view that the income gap in the country is too large, articulated a strong preference for a more equitable social structure, and acknowledged the class and social tensions that economic inequality has produced. There is also a preference for a narrowing of earnings disparities, a more generous minimum wage, and regulatory limits on executive pay. While this suggests a desire for fair and legitimate remuneration, the analysis also reveals that South Africans are willing to tolerate fairly high levels of inequality. Nonetheless, these beliefs are generally interpreted as a desire for a more equitable and fair society. This preference for change is reflected in a fairly strong belief that government should assume responsibility for reducing material disparities. One’s social position, mobility history, awareness of inequality, political leaning and racial attitudes all have a bearing on how weak and strong this predisposition is, but the normative demand for political redistribution remains fairly widely shared irrespective of these individual traits. Greater polarisation is however evident with respect to redistributive social policy, especially measures designed to overcome historical racial injustice (affirmative action, sports quotas, and land reform). These intergroup differences converge considerably when referring to class-based policy measures. One surprising finding is the evidence that South Africa’s youngest generation, the so-called ‘Born Frees’, tend to adopt a similar predisposition to redress policy as older generations, thus confounding expectations of a post-apartheid value change. I conclude by arguing that there seems to be a firmer basis for a social compact about preferences for interventions designed to produce a more just society than is typically assumed. Intractably high levels of economic inequality during the country’s first quarter-century of democracy is resulting in a growing recognition of the need for a stronger policy emphasis on economic inequality in South Africa over coming decades if the vision enshrined in the Freedom Charter and the Constitution is to be realised. South Africans may not be able to fully agree about the specific elements that constitute a socially just response to economic inequality. Yet, the common identification of and concern with redressable injustice, coupled with a broad-based commitment to government redistribution and classbased social policies, could serve as a foundation on which to rekindle the solidaristic spirit of 1994 and forge progress towards a more equitable society.
- Full Text:
- Date Issued: 2019
Investigating mathematical proficiency testing in Namibian school high stakes mathematics examinations: an exploratory study
- Authors: Ndjendja, Elizabeth
- Date: 2019
- Subjects: Education and state -- Namibia , Educational tests and measurements -- Namibia , Mathematics -- Curricula -- Namibia , Mathematics -- Study and teaching -- Namibia , Namibia. Ministry of Education -- Examinations
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/92887 , vital:30759
- Description: The Namibian government has put processes in place to continuously improve its education system in line with educational development in the world. The education reform efforts are administered and coordinated by the Ministry of Education, Arts and Culture. At the centre of these reform efforts are curriculum policy documents and subject syllabuses with the intention of improving the teaching and learning process in the classrooms. These reform efforts appears to overlook the positive influence high stakes assessment has on the teaching and learning process. The study reported in this thesis was designed to investigate the feasibility of assessing separate elements of mathematical proficiency in the high stakes Mathematics assessment in Namibia. The study was designed as a developmental, exploratory research that collected and analysed both qualitative and quantitative data in order to respond to issues raised by five specific research objectives. The data collected enabled the adaptation of some assessment tools in order to distinctly assess selected mathematical proficiency categories. The results further indicated that the envisaged proficiency assessment system could be used to characterise the examination question papers and revealed insights into the conceptualisation of the current assessment system. The results further indicated the visible distinguishability of different elements of proficiency through the developed tools and the learners’ responses to the NSSCO examination. Finally, constrains and affordance which the original assessment system has in relation to the developed system were revealed and addressed. In closing, the research suggested changes and possible adaptation of assessment tools to ensure the proper assessment of mathematical proficiency aspects through high stakes assessment. Immerging issues that needed further research were also highlighted.
- Full Text:
- Date Issued: 2019
- Authors: Ndjendja, Elizabeth
- Date: 2019
- Subjects: Education and state -- Namibia , Educational tests and measurements -- Namibia , Mathematics -- Curricula -- Namibia , Mathematics -- Study and teaching -- Namibia , Namibia. Ministry of Education -- Examinations
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/92887 , vital:30759
- Description: The Namibian government has put processes in place to continuously improve its education system in line with educational development in the world. The education reform efforts are administered and coordinated by the Ministry of Education, Arts and Culture. At the centre of these reform efforts are curriculum policy documents and subject syllabuses with the intention of improving the teaching and learning process in the classrooms. These reform efforts appears to overlook the positive influence high stakes assessment has on the teaching and learning process. The study reported in this thesis was designed to investigate the feasibility of assessing separate elements of mathematical proficiency in the high stakes Mathematics assessment in Namibia. The study was designed as a developmental, exploratory research that collected and analysed both qualitative and quantitative data in order to respond to issues raised by five specific research objectives. The data collected enabled the adaptation of some assessment tools in order to distinctly assess selected mathematical proficiency categories. The results further indicated that the envisaged proficiency assessment system could be used to characterise the examination question papers and revealed insights into the conceptualisation of the current assessment system. The results further indicated the visible distinguishability of different elements of proficiency through the developed tools and the learners’ responses to the NSSCO examination. Finally, constrains and affordance which the original assessment system has in relation to the developed system were revealed and addressed. In closing, the research suggested changes and possible adaptation of assessment tools to ensure the proper assessment of mathematical proficiency aspects through high stakes assessment. Immerging issues that needed further research were also highlighted.
- Full Text:
- Date Issued: 2019
A dynamics based analysis of allosteric modulation in heat shock proteins
- Authors: Penkler, David Lawrence
- Date: 2019
- Subjects: Heat shock proteins , Molecular chaperones , Allosteric regulation , Homeostasis , Protein kinases , Transcription factors , Adenosine triphosphatase , Cancer -- Chemotherapy , Molecular dynamics , High throughput screening (Drug development)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/115948 , vital:34273
- Description: The 70 kDa and 90 kDa heat shock proteins (Hsp70 and Hsp90) are molecular chaperones that play central roles in maintaining cellular homeostasis in all organisms of life with the exception of archaea. In addition to their general chaperone function in protein quality control, Hsp70 and Hsp90 cooperate in the regulation and activity of some 200 known natively folded protein clients which include protein kinases, transcription factors and receptors, many of which are implicated as key regulators of essential signal transduction pathways. Both chaperones are considered to be large multi-domain proteins that rely on ATPase activity and co-chaperone interactions to regulate their conformational cycles for peptide binding and release. The unique positioning of Hsp90 at the crossroads of several fundamental cellular pathways coupled with its known association with diverse oncogenic peptide clients has brought the molecular chaperone under increasing interest as a potential anti-cancer target that is crucially implicated with all eight hallmarks of the disease. Current orthosteric drug discovery efforts aimed at the inhibition of the ATPase domain of Hsp90 have been limited due to high levels of associated toxicity. In an effort to circumnavigate this, the combined focus of research efforts is shifting toward alternative approaches such as interference with co-chaperone binding and the allosteric inhibition/activation of the molecular chaperone. The overriding aim of this thesis was to demonstrate how the computational technique of Perturbation response scanning (PRS) coupled with all-atom molecular dynamics simulations (MD) and dynamic residue interaction network (DRN) analysis can be used as a viable strategy to efficiently scan and accurately identify allosteric control element capable of modulating the functional dynamics of a protein. In pursuit of this goal, this thesis also contributes to the current understanding of the nucleotide dependent allosteric mechanisms at play in cellular functionality of both Hsp70 and Hsp90. All-atom MD simulations of E. coli DnaK provided evidence of nucleotide driven modulation of conformational dynamics in both the catalytically active and inactive states. PRS analysis employed on these trajectories demonstrated sensitivity toward bound nucleotide and peptide substrate, and provided evidence of a putative allosterically active intermediate state between the ATPase active and inactive conformational states. Simultaneous binding of ATP and peptide substrate was found to allosterically prime the chaperone for interstate conversion regardless of the transition direction. Detailed analysis of these allosterically primed states revealed select residue sites capable of selecting a coordinate shift towards the opposite conformational state. In an effort to validate these results, the predicted allosteric hot spot sites were cross-validated with known experimental works and found to overlap with functional sites implicated in allosteric signal propagation and ATPase activation in Hsp70. This study presented for the first time, the application of PRS as a suitable diagnostic tool for the elucidation and quantification of the allosteric potential of select residues to effect functionally relevant global conformational rearrangements. The PRS methodology described in this study was packaged within the Python programming environment in the MD-TASK software suite for command-line ease of use and made freely available. Homology modelling techniques were used to address the lack of experimental structural data for the human cytosolic isoform of Hsp90 and for the first time provided accurate full-length structural models of human Hsp90α in fully-closed and partially-open conformations. Long-range all-atom MD simulations of these structures revealed nucleotide driven modulation of conformational dynamics in Hsp90. Subsequent DRN and PRS analysis of these MD trajectories allowed for the quantification and elucidation of nucleotide driven allosteric modulation in the molecular chaperone. A detailed PRS analysis revealed allosteric inter-domain coupling between the extreme terminals of the chaperone in response to external force perturbations at either domain. Furthermore PRS also identified several individual residue sites that are capable of selecting conformational rearrangements towards functionally relevant states which may be considered to be putative allosteric target sites for future drug discovery efforts Molecular docking techniques were employed to investigate the modulation of conformational dynamics of human Hsp90α in response to ligand binding interactions at two identified allosteric sites at the C-terminal. High throughput screening of a small library of natural compounds indigenous to South Africa revealed three hit compounds at these sites: Cephalostatin 17, 20(29)-Lupene-3β isoferulate and 3'-Bromorubrolide F. All-atom MD simulations on these protein-ligand complexes coupled with DRN analysis and several advanced trajectory based analysis techniques provided evidence of selective allosteric modulation of Hsp90α conformational dynamics in response to the identity and location of the bound ligands. Ligands bound at the four-helix bundle presented as putative allosteric inhibitors of Hsp90α, driving conformational dynamics in favour of dimer opening and possibly dimer separation. Meanwhile, ligand interactions at an adjacent sub-pocket located near the interface between the middle and C-terminal domains demonstrated allosteric activation of the chaperone, modulating conformational dynamics in favour of the fully-closed catalytically active conformational state. Taken together, the data presented in this thesis contributes to the understanding of allosteric modulation of conformational dynamics in Hsp70 and Hsp90, and provides a suitable platform for future biochemical and drug discovery studies. Furthermore, the molecular docking and computational identification of allosteric compounds with suitable binding affinity for allosteric sites at the CTD of human Hsp90α provide for the first time “proof-of-principle” for the use of PRS in conjunction with MD simulations and DRN analysis as a suitable method for the rapid identification of allosteric sites in proteins that can be probed by small molecule interaction. The data presented in this section could pave the way for future allosteric drug discovery studies for the treatment of Hsp90 associated pathologies.
- Full Text:
- Date Issued: 2019
- Authors: Penkler, David Lawrence
- Date: 2019
- Subjects: Heat shock proteins , Molecular chaperones , Allosteric regulation , Homeostasis , Protein kinases , Transcription factors , Adenosine triphosphatase , Cancer -- Chemotherapy , Molecular dynamics , High throughput screening (Drug development)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/115948 , vital:34273
- Description: The 70 kDa and 90 kDa heat shock proteins (Hsp70 and Hsp90) are molecular chaperones that play central roles in maintaining cellular homeostasis in all organisms of life with the exception of archaea. In addition to their general chaperone function in protein quality control, Hsp70 and Hsp90 cooperate in the regulation and activity of some 200 known natively folded protein clients which include protein kinases, transcription factors and receptors, many of which are implicated as key regulators of essential signal transduction pathways. Both chaperones are considered to be large multi-domain proteins that rely on ATPase activity and co-chaperone interactions to regulate their conformational cycles for peptide binding and release. The unique positioning of Hsp90 at the crossroads of several fundamental cellular pathways coupled with its known association with diverse oncogenic peptide clients has brought the molecular chaperone under increasing interest as a potential anti-cancer target that is crucially implicated with all eight hallmarks of the disease. Current orthosteric drug discovery efforts aimed at the inhibition of the ATPase domain of Hsp90 have been limited due to high levels of associated toxicity. In an effort to circumnavigate this, the combined focus of research efforts is shifting toward alternative approaches such as interference with co-chaperone binding and the allosteric inhibition/activation of the molecular chaperone. The overriding aim of this thesis was to demonstrate how the computational technique of Perturbation response scanning (PRS) coupled with all-atom molecular dynamics simulations (MD) and dynamic residue interaction network (DRN) analysis can be used as a viable strategy to efficiently scan and accurately identify allosteric control element capable of modulating the functional dynamics of a protein. In pursuit of this goal, this thesis also contributes to the current understanding of the nucleotide dependent allosteric mechanisms at play in cellular functionality of both Hsp70 and Hsp90. All-atom MD simulations of E. coli DnaK provided evidence of nucleotide driven modulation of conformational dynamics in both the catalytically active and inactive states. PRS analysis employed on these trajectories demonstrated sensitivity toward bound nucleotide and peptide substrate, and provided evidence of a putative allosterically active intermediate state between the ATPase active and inactive conformational states. Simultaneous binding of ATP and peptide substrate was found to allosterically prime the chaperone for interstate conversion regardless of the transition direction. Detailed analysis of these allosterically primed states revealed select residue sites capable of selecting a coordinate shift towards the opposite conformational state. In an effort to validate these results, the predicted allosteric hot spot sites were cross-validated with known experimental works and found to overlap with functional sites implicated in allosteric signal propagation and ATPase activation in Hsp70. This study presented for the first time, the application of PRS as a suitable diagnostic tool for the elucidation and quantification of the allosteric potential of select residues to effect functionally relevant global conformational rearrangements. The PRS methodology described in this study was packaged within the Python programming environment in the MD-TASK software suite for command-line ease of use and made freely available. Homology modelling techniques were used to address the lack of experimental structural data for the human cytosolic isoform of Hsp90 and for the first time provided accurate full-length structural models of human Hsp90α in fully-closed and partially-open conformations. Long-range all-atom MD simulations of these structures revealed nucleotide driven modulation of conformational dynamics in Hsp90. Subsequent DRN and PRS analysis of these MD trajectories allowed for the quantification and elucidation of nucleotide driven allosteric modulation in the molecular chaperone. A detailed PRS analysis revealed allosteric inter-domain coupling between the extreme terminals of the chaperone in response to external force perturbations at either domain. Furthermore PRS also identified several individual residue sites that are capable of selecting conformational rearrangements towards functionally relevant states which may be considered to be putative allosteric target sites for future drug discovery efforts Molecular docking techniques were employed to investigate the modulation of conformational dynamics of human Hsp90α in response to ligand binding interactions at two identified allosteric sites at the C-terminal. High throughput screening of a small library of natural compounds indigenous to South Africa revealed three hit compounds at these sites: Cephalostatin 17, 20(29)-Lupene-3β isoferulate and 3'-Bromorubrolide F. All-atom MD simulations on these protein-ligand complexes coupled with DRN analysis and several advanced trajectory based analysis techniques provided evidence of selective allosteric modulation of Hsp90α conformational dynamics in response to the identity and location of the bound ligands. Ligands bound at the four-helix bundle presented as putative allosteric inhibitors of Hsp90α, driving conformational dynamics in favour of dimer opening and possibly dimer separation. Meanwhile, ligand interactions at an adjacent sub-pocket located near the interface between the middle and C-terminal domains demonstrated allosteric activation of the chaperone, modulating conformational dynamics in favour of the fully-closed catalytically active conformational state. Taken together, the data presented in this thesis contributes to the understanding of allosteric modulation of conformational dynamics in Hsp70 and Hsp90, and provides a suitable platform for future biochemical and drug discovery studies. Furthermore, the molecular docking and computational identification of allosteric compounds with suitable binding affinity for allosteric sites at the CTD of human Hsp90α provide for the first time “proof-of-principle” for the use of PRS in conjunction with MD simulations and DRN analysis as a suitable method for the rapid identification of allosteric sites in proteins that can be probed by small molecule interaction. The data presented in this section could pave the way for future allosteric drug discovery studies for the treatment of Hsp90 associated pathologies.
- Full Text:
- Date Issued: 2019