Bioinformatic analysis of Aminoacyl tRNA Synthetases as potential antimalarial drug targets
- Authors: Nyamai, Dorothy Wavinya
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/164579 , vital:41142 , doi:10.21504/10962/164579
- Description: Thesis (PhD)--Rhodes University, Faculty of Science, Biochemistry and Microbiology, 2020
- Full Text:
- Date Issued: 2020
- Authors: Nyamai, Dorothy Wavinya
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/164579 , vital:41142 , doi:10.21504/10962/164579
- Description: Thesis (PhD)--Rhodes University, Faculty of Science, Biochemistry and Microbiology, 2020
- Full Text:
- Date Issued: 2020
BODIPY dyes for use in nonlinear optics and optical sensing
- Authors: Kubheka, Gugu Patience
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/163352 , vital:41032 , doi:10.21504/10962/163352
- Description: Thesis (PhD)--Rhodes University, Faculty of Science, Department of Chemistry, 2020.
- Full Text:
- Date Issued: 2020
- Authors: Kubheka, Gugu Patience
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/163352 , vital:41032 , doi:10.21504/10962/163352
- Description: Thesis (PhD)--Rhodes University, Faculty of Science, Department of Chemistry, 2020.
- Full Text:
- Date Issued: 2020
Carnivore intra-guild competition in Selati Game Reserve, Limpopo Province, South Africa
- Authors: Comley, Jessica
- Date: 2020
- Subjects: Hyenas -- Behavior -- South Africa , Hyenas -- South Africa , Hyenas -- Ecology -- South Africa , Top predators -- South Africa , Top predators -- Ecology -- South Africa , Animal communities -- South Africa , Animal behavior -- South Africa , Mutualism (Biology) -- South Africa , Coexistence of species -- South Africa , Game farms -- South Africa , Selati Game Reserve (South Africa)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/115558 , vital:34163
- Description: Carnivore intra-guild interactions can be important drivers of carnivore community composition and ecosystem functioning. Large carnivores are particularly important since they occupy the highest trophic levels and can exert extensive influences on subordinate carnivores and prey species. Given Africa’s rapidly expanding human population, enclosed reserves such as those found in South Africa, may become increasingly important for carnivore conservation. A major concern, however, is that the interactions and co-existence of multiple carnivores in these systems is poorly understood. Additionally, the majority of reserves in South Africa are small ( 400km²), potentially increasing the likelihood of competition. My research aimed to provide insight into the interactions and co-existence of a multi-carnivore community within a small, enclosed reserve in South Africa (Selati Game Reserve). I tackled this task by using a combination of field techniques including camera trap surveys, ungulate transect surveys, aerial count surveys, location data collected from collared large carnivores and scat and kill site analyses. I found that carnivore-carnivore interactions, and their associated impacts, varied within the carnivore guild and that co-existence may be due to trade-offs between various risks (i.e. interference and exploitative competition) and benefits (i.e. resources such as food and space). My findings also revealed that large carnivores, such as lions (Panthera leo), spotted hyaenas (Crocuta crocuta) and leopards (Panthera pardus) do not have homogenous effects and that site-specific research on multiple-carnivores is integral for conserving biodiversity and ecosystem dynamics. Lions were the dominant large carnivore (in terms of intra-guild predation, space use and resource use) despite being outnumbered seven to one by spotted hyaenas. Leopard occupancy was negatively influenced by lions and leopard diet overlapped almost completely (91%) with spotted hyaenas, suggesting increased kleptoparasitism of leopard kills by spotted hyaenas. While my study provides valuable insight into the complexity of carnivore intra-guild competition in a small, enclosed reserve it also highlights major research gaps and emphasises the need for ecosystem-based research throughout southern Africa to fully understand how multiple sympatric carnivores co-exist in these systems.
- Full Text:
- Date Issued: 2020
- Authors: Comley, Jessica
- Date: 2020
- Subjects: Hyenas -- Behavior -- South Africa , Hyenas -- South Africa , Hyenas -- Ecology -- South Africa , Top predators -- South Africa , Top predators -- Ecology -- South Africa , Animal communities -- South Africa , Animal behavior -- South Africa , Mutualism (Biology) -- South Africa , Coexistence of species -- South Africa , Game farms -- South Africa , Selati Game Reserve (South Africa)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/115558 , vital:34163
- Description: Carnivore intra-guild interactions can be important drivers of carnivore community composition and ecosystem functioning. Large carnivores are particularly important since they occupy the highest trophic levels and can exert extensive influences on subordinate carnivores and prey species. Given Africa’s rapidly expanding human population, enclosed reserves such as those found in South Africa, may become increasingly important for carnivore conservation. A major concern, however, is that the interactions and co-existence of multiple carnivores in these systems is poorly understood. Additionally, the majority of reserves in South Africa are small ( 400km²), potentially increasing the likelihood of competition. My research aimed to provide insight into the interactions and co-existence of a multi-carnivore community within a small, enclosed reserve in South Africa (Selati Game Reserve). I tackled this task by using a combination of field techniques including camera trap surveys, ungulate transect surveys, aerial count surveys, location data collected from collared large carnivores and scat and kill site analyses. I found that carnivore-carnivore interactions, and their associated impacts, varied within the carnivore guild and that co-existence may be due to trade-offs between various risks (i.e. interference and exploitative competition) and benefits (i.e. resources such as food and space). My findings also revealed that large carnivores, such as lions (Panthera leo), spotted hyaenas (Crocuta crocuta) and leopards (Panthera pardus) do not have homogenous effects and that site-specific research on multiple-carnivores is integral for conserving biodiversity and ecosystem dynamics. Lions were the dominant large carnivore (in terms of intra-guild predation, space use and resource use) despite being outnumbered seven to one by spotted hyaenas. Leopard occupancy was negatively influenced by lions and leopard diet overlapped almost completely (91%) with spotted hyaenas, suggesting increased kleptoparasitism of leopard kills by spotted hyaenas. While my study provides valuable insight into the complexity of carnivore intra-guild competition in a small, enclosed reserve it also highlights major research gaps and emphasises the need for ecosystem-based research throughout southern Africa to fully understand how multiple sympatric carnivores co-exist in these systems.
- Full Text:
- Date Issued: 2020
Child marriage as a hindrance to the realisation of child rights in Zimbabwe: consolidated approaches towards eradication
- Authors: Ndhlovu, Ntandokayise
- Date: 2020
- Subjects: Teenage marriage Children's rights
- Language: English
- Type: Thesis , Doctoral , LLD
- Identifier: http://hdl.handle.net/10353/18359 , vital:42256
- Description: Child marriage is defined as any marriage where one of the spouses is younger than 18 years old. A number of deep, complex, interrelated and interlinked factors are responsible for the practice in Zimbabwe and elsewhere. These include the weak enforcement of existing laws, legal contradictions, slow alignment of laws to the Constitution and international child rights, entrenched harmful religious and cultural practices, and acute poverty. It was at the fulcrum of this dissertation thus to examine the unfair limitations caused by child marriage, on the realisation and enjoyment of child rights in Zimbabwe. The United Nations International Children’s Emergency Fund reported an estimated 31 percent prevalence of the scourge in the country. These percentages translate to millions of children, and the numbers could be on the rise. Child marriage has intense consequences for the realisation and enjoyment of rights by many children in Zimbabwe. Of note, child marriage ends childhoods. It impairs the children’s right to education, minimises their economic opportunities and fair chances in life, and increases their vulnerability to domestic violence, marital rape and sexually transmitted diseases. The grave ramifications of child marriage, in terms of the realisation of child rights have led to a number of international, regional and national efforts to curb this scourge. However, owing to an array of multifaceted and complex causes, the practice remains highly prevalent in Zimbabwe. After decades of side-lining, child rights in Zimbabwe, have finally gained constitutional protection under the 2013 Constitution. While the comprehensive protection of child rights as justiciable rights is an acceptable standard, a plethora of practices such as child marriage are a practical and real threat to the realisation of these rights. Therefore, it is incumbent upon Zimbabwe to ensure that child rights as stipulated in the Constitution are respected, promoted, protected and fulfilled. The elimination of child marriage is a daunting yet possible task. Through desktop based qualitative research, this dissertation ascertained the main drivers of the practice in the country, and its impact on the realisation of fundamental child rights in Zimbabwe. The study further explored the contribution, as well as the insufficiencies of International and African Human Rights systems, to the protection of children from child marriage. It also assesses the prospects and challenges of the existing domestic (legislative and constitutional norms) in protecting child rights in the Southern African country. The impetus behind this iii examination is to recommend a comprehensive and holistic effort to curb child marriage and suggest a consolidated legal and non-legal approach to end it
- Full Text:
- Date Issued: 2020
- Authors: Ndhlovu, Ntandokayise
- Date: 2020
- Subjects: Teenage marriage Children's rights
- Language: English
- Type: Thesis , Doctoral , LLD
- Identifier: http://hdl.handle.net/10353/18359 , vital:42256
- Description: Child marriage is defined as any marriage where one of the spouses is younger than 18 years old. A number of deep, complex, interrelated and interlinked factors are responsible for the practice in Zimbabwe and elsewhere. These include the weak enforcement of existing laws, legal contradictions, slow alignment of laws to the Constitution and international child rights, entrenched harmful religious and cultural practices, and acute poverty. It was at the fulcrum of this dissertation thus to examine the unfair limitations caused by child marriage, on the realisation and enjoyment of child rights in Zimbabwe. The United Nations International Children’s Emergency Fund reported an estimated 31 percent prevalence of the scourge in the country. These percentages translate to millions of children, and the numbers could be on the rise. Child marriage has intense consequences for the realisation and enjoyment of rights by many children in Zimbabwe. Of note, child marriage ends childhoods. It impairs the children’s right to education, minimises their economic opportunities and fair chances in life, and increases their vulnerability to domestic violence, marital rape and sexually transmitted diseases. The grave ramifications of child marriage, in terms of the realisation of child rights have led to a number of international, regional and national efforts to curb this scourge. However, owing to an array of multifaceted and complex causes, the practice remains highly prevalent in Zimbabwe. After decades of side-lining, child rights in Zimbabwe, have finally gained constitutional protection under the 2013 Constitution. While the comprehensive protection of child rights as justiciable rights is an acceptable standard, a plethora of practices such as child marriage are a practical and real threat to the realisation of these rights. Therefore, it is incumbent upon Zimbabwe to ensure that child rights as stipulated in the Constitution are respected, promoted, protected and fulfilled. The elimination of child marriage is a daunting yet possible task. Through desktop based qualitative research, this dissertation ascertained the main drivers of the practice in the country, and its impact on the realisation of fundamental child rights in Zimbabwe. The study further explored the contribution, as well as the insufficiencies of International and African Human Rights systems, to the protection of children from child marriage. It also assesses the prospects and challenges of the existing domestic (legislative and constitutional norms) in protecting child rights in the Southern African country. The impetus behind this iii examination is to recommend a comprehensive and holistic effort to curb child marriage and suggest a consolidated legal and non-legal approach to end it
- Full Text:
- Date Issued: 2020
CO2-induced woody thickening depends strongly on interacting abiotic and biotic factors
- Authors: Raubenheimer, Sarah Lynn
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/164646 , vital:41151 , doi:10.21504/10962/164646
- Description: Thesis (PhD)--Rhodes University, Faculty of Science, Botany, 2020
- Full Text:
- Date Issued: 2020
- Authors: Raubenheimer, Sarah Lynn
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/164646 , vital:41151 , doi:10.21504/10962/164646
- Description: Thesis (PhD)--Rhodes University, Faculty of Science, Botany, 2020
- Full Text:
- Date Issued: 2020
Commercial maritime higher education needs in South Africa
- Authors: Allison, Lee-Anne
- Date: 2020
- Subjects: Education, Higher -- Curricula , Education, Higher -- Research Merchant marine Shipping -- Economic aspects
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/50350 , vital:42111
- Description: Seaborne cargo trade accounts for over 80% of the physical volume of global trade. Maritime transport thus fulfils an integral function in the economy of the world. South Africa generates approximately 3.5% of the world’s seaborne trade by value and 1.61% by tonnage; but the business of shipping all that cargo is undertaken by foreign firms. Operation Phakisa, the Comprehensive Maritime Transport Policy and the South African Maritime Road Map, in pursuance of the National Development Plan, aim to revive the commercial maritime sector. In order to meet the demand for the skills and innovative abilities sought at executive and managerial levels in the commercial maritime sector, higher education in the knowledge of maritime business is increasingly becoming a prerequisite. Investment in higher education of quality and relevance in the maritime field would contribute to achieving the goals of the government for harnessing the potential of South Africa’s blue economy. The literature is researched in order to establish an authoritative view that the knowledge and the inspiration for entrepreneurial activity in the maritime sector can be imparted through higher education; and for example, that a viable shipping sector can contribute to the growth of a country’s economy. The South African maritime sector is then described. The commercial maritime higher education available at universities and other institutions of higher learning in South Africa, as well as in other African countries and elsewhere in the world, is examined, in order to be able to identify the degree and diploma courses available. Maritime courses imply not only the content of the educational material, but also the method whereby the knowledge is instilled in learners, and which extends well beyond the classroom. A survey, by way of the personal interviews of leaders in maritime business, maritime government affairs, and academics teaching maritime topics, is then undertaken to ascertain their views on the education required to promote the maritime sector in South Africa, using the list of subjects available for study worldwide, to assist their choice. The literature research and the interview survey by design also enable the secondary aims of the study to be achieved. Those aims include determining how awareness of the maritime domain could be raised and how co-operation between academia, business and government, known as the triple helix could be organised, to promote the growth of the maritime sector. The results of the survey are analysed and tabulated, in order to illustrate the extent of the agreement between those interviewed and the conclusions reached. These conclusions establish: that the commercial maritime education currently available in South Africa, is inadequate to meet the aim of the government to the sector; that a post-graduate degree in the specified maritime studies incorporating a period of internship, and following on a first degree in business subjects, is required; that a triple helix of co-operation between academia, business and the government is essential to grow the commercial maritime sector in which South African entrepreneurs educated in such business will have the advantage; that greater awareness of the maritime domain is essential in South Africa if entrepreneurship in maritime business is to be cultivated; and that such awareness can be cultivated in various ways; but it should start by including more maritime topics in the current school curricula.
- Full Text:
- Date Issued: 2020
- Authors: Allison, Lee-Anne
- Date: 2020
- Subjects: Education, Higher -- Curricula , Education, Higher -- Research Merchant marine Shipping -- Economic aspects
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/50350 , vital:42111
- Description: Seaborne cargo trade accounts for over 80% of the physical volume of global trade. Maritime transport thus fulfils an integral function in the economy of the world. South Africa generates approximately 3.5% of the world’s seaborne trade by value and 1.61% by tonnage; but the business of shipping all that cargo is undertaken by foreign firms. Operation Phakisa, the Comprehensive Maritime Transport Policy and the South African Maritime Road Map, in pursuance of the National Development Plan, aim to revive the commercial maritime sector. In order to meet the demand for the skills and innovative abilities sought at executive and managerial levels in the commercial maritime sector, higher education in the knowledge of maritime business is increasingly becoming a prerequisite. Investment in higher education of quality and relevance in the maritime field would contribute to achieving the goals of the government for harnessing the potential of South Africa’s blue economy. The literature is researched in order to establish an authoritative view that the knowledge and the inspiration for entrepreneurial activity in the maritime sector can be imparted through higher education; and for example, that a viable shipping sector can contribute to the growth of a country’s economy. The South African maritime sector is then described. The commercial maritime higher education available at universities and other institutions of higher learning in South Africa, as well as in other African countries and elsewhere in the world, is examined, in order to be able to identify the degree and diploma courses available. Maritime courses imply not only the content of the educational material, but also the method whereby the knowledge is instilled in learners, and which extends well beyond the classroom. A survey, by way of the personal interviews of leaders in maritime business, maritime government affairs, and academics teaching maritime topics, is then undertaken to ascertain their views on the education required to promote the maritime sector in South Africa, using the list of subjects available for study worldwide, to assist their choice. The literature research and the interview survey by design also enable the secondary aims of the study to be achieved. Those aims include determining how awareness of the maritime domain could be raised and how co-operation between academia, business and government, known as the triple helix could be organised, to promote the growth of the maritime sector. The results of the survey are analysed and tabulated, in order to illustrate the extent of the agreement between those interviewed and the conclusions reached. These conclusions establish: that the commercial maritime education currently available in South Africa, is inadequate to meet the aim of the government to the sector; that a post-graduate degree in the specified maritime studies incorporating a period of internship, and following on a first degree in business subjects, is required; that a triple helix of co-operation between academia, business and the government is essential to grow the commercial maritime sector in which South African entrepreneurs educated in such business will have the advantage; that greater awareness of the maritime domain is essential in South Africa if entrepreneurship in maritime business is to be cultivated; and that such awareness can be cultivated in various ways; but it should start by including more maritime topics in the current school curricula.
- Full Text:
- Date Issued: 2020
Commercial maritime higher education needs in South Africa
- Authors: Allison, Lee-Ann
- Date: 2020
- Subjects: Marine resources
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/47496 , vital:40117
- Description: Seaborne cargo trade accounts for over 80% of the physical volume of global trade. Maritime transport thus fulfills an integral function in the economy of the world. South Africa generates approximately 3.5% of the world’s seaborne trade by value and 1.61% by tonnage, but the business of shipping all that cargo is undertaken by foreign firms. Operation Phakisa, the Comprehensive Maritime Transport Policy, and the South African Maritime Road Map, in pursuance of the National Development Plan, aim to revive the commercial maritime sector. In order to meet the demand for the skills and innovative abilities sought at executive and managerial levels in the commercial maritime sector, higher education in the knowledge of maritime business is increasingly becoming a prerequisite. Investment in higher education of quality and relevance in the maritime field would contribute to achieving the goals of the government for harnessing the potential of South Africa’s blue economy. The literature is researched in order to establish an authoritative view that the knowledge and the inspiration for entrepreneurial activity in the maritime sector can be imparted through higher education; and for example, that a viable shipping sector can contribute to the growth of a country’s economy. The South African maritime sector is then described. The commercial maritime higher education available at universities and other institutions of higher learning in South Africa, as well as in other African countries and elsewhere in the world, is examined, in order to be able to identify the degree and diploma courses available. Maritime courses imply not only the content of the educational material, but also the method whereby the knowledge is instilled in learners, and which extends well beyond the classroom. A survey, by way of the personal interviews of leaders in maritime business, maritime government affairs, and academics teaching maritime topics, is then undertaken to ascertain their views on the education required to promote the maritime sector in South Africa, using the list of subjects available for study worldwide, to assist their choice. The literature research and the interview survey by design also enable the secondary aims of the study to be achieved. Those aims include determining how awareness of the maritime domain could be raised and how co-operation between academia, business, and government, known as the triple helix could be organized, to promote the growth of the maritime sector. The results of the survey are analyzed and tabulated, in order to illustrate the extent of the agreement between those interviewed and the conclusions reached. These conclusions establish: (i) that the commercial maritime education currently available in South Africa, is inadequate to meet the aim of the government to the sector; (ii) that a post-graduate degree iv in the specified maritime studies incorporating a period of internship, and following on the first degree in business subjects, is required; (iii) that a triple helix of co-operation between academia, business, and the government is essential to grow the commercial maritime sector in which South African entrepreneurs educated in such business will have the advantage; (iv) that greater awareness of the maritime domain is essential in South Africa if entrepreneurship in maritime business is to be cultivated; and (v)that such awareness can be cultivated in various ways; but it should start by including more maritime topics in the current school curricula.
- Full Text:
- Date Issued: 2020
- Authors: Allison, Lee-Ann
- Date: 2020
- Subjects: Marine resources
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/47496 , vital:40117
- Description: Seaborne cargo trade accounts for over 80% of the physical volume of global trade. Maritime transport thus fulfills an integral function in the economy of the world. South Africa generates approximately 3.5% of the world’s seaborne trade by value and 1.61% by tonnage, but the business of shipping all that cargo is undertaken by foreign firms. Operation Phakisa, the Comprehensive Maritime Transport Policy, and the South African Maritime Road Map, in pursuance of the National Development Plan, aim to revive the commercial maritime sector. In order to meet the demand for the skills and innovative abilities sought at executive and managerial levels in the commercial maritime sector, higher education in the knowledge of maritime business is increasingly becoming a prerequisite. Investment in higher education of quality and relevance in the maritime field would contribute to achieving the goals of the government for harnessing the potential of South Africa’s blue economy. The literature is researched in order to establish an authoritative view that the knowledge and the inspiration for entrepreneurial activity in the maritime sector can be imparted through higher education; and for example, that a viable shipping sector can contribute to the growth of a country’s economy. The South African maritime sector is then described. The commercial maritime higher education available at universities and other institutions of higher learning in South Africa, as well as in other African countries and elsewhere in the world, is examined, in order to be able to identify the degree and diploma courses available. Maritime courses imply not only the content of the educational material, but also the method whereby the knowledge is instilled in learners, and which extends well beyond the classroom. A survey, by way of the personal interviews of leaders in maritime business, maritime government affairs, and academics teaching maritime topics, is then undertaken to ascertain their views on the education required to promote the maritime sector in South Africa, using the list of subjects available for study worldwide, to assist their choice. The literature research and the interview survey by design also enable the secondary aims of the study to be achieved. Those aims include determining how awareness of the maritime domain could be raised and how co-operation between academia, business, and government, known as the triple helix could be organized, to promote the growth of the maritime sector. The results of the survey are analyzed and tabulated, in order to illustrate the extent of the agreement between those interviewed and the conclusions reached. These conclusions establish: (i) that the commercial maritime education currently available in South Africa, is inadequate to meet the aim of the government to the sector; (ii) that a post-graduate degree iv in the specified maritime studies incorporating a period of internship, and following on the first degree in business subjects, is required; (iii) that a triple helix of co-operation between academia, business, and the government is essential to grow the commercial maritime sector in which South African entrepreneurs educated in such business will have the advantage; (iv) that greater awareness of the maritime domain is essential in South Africa if entrepreneurship in maritime business is to be cultivated; and (v)that such awareness can be cultivated in various ways; but it should start by including more maritime topics in the current school curricula.
- Full Text:
- Date Issued: 2020
Comparative analysis of the known Hop1b and the novel Hop1a isoforms of the Hop gene
- Authors: Makhubu, Portia
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/164311 , vital:41108 , doi:10.21504/10962/164311
- Description: Thesis (PhD)--Rhodes University, Faculty of Science, Biochemistry and Microbiology, 2020
- Full Text:
- Date Issued: 2020
- Authors: Makhubu, Portia
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/164311 , vital:41108 , doi:10.21504/10962/164311
- Description: Thesis (PhD)--Rhodes University, Faculty of Science, Biochemistry and Microbiology, 2020
- Full Text:
- Date Issued: 2020
Comprehensive characterization of the antidiabetic potential of selected plants and macrofungi from Africa using an in vitro target-directed screening platform and cellomics
- Authors: Pringle, Nadine Alex
- Date: 2020
- Subjects: Hypoglycemic agents
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/46750 , vital:39653
- Description: Several synthetic antidiabetic drugs have been developed to date, however, most are accompanied by adverse side-effects while remaining expensive and largely inaccessible to the vast majority of those who need it. To provide enough scientific evidence to support the inclusion of more affordable African antidiabetic medicinal plants and macrofungi into healthcare programs, this study sought out to develop a comprehensive in vitro antidiabetic target-directed screening platform incorporating high content screening and analysis/ cellomics. To test the success of this model, the potential antidiabetic mechanisms of five plants (Aspalathus linearis, Brachylaena discolor, Carpobrotus deliciosus, Sutherlandia frutescens and Tarchonanthus camphoratus) and two macrofungal species (Ganoderma lucidum and Hericium erinaceus) were explored. The screening model consisted of approximately 22 assays exploring the antidiabetic effects of selected aqueous and ethanolic extracts in five well-characterised antidiabetic targets: the intestine, liver, skeletal muscle, adipose tissue/ obesity and pancreatic β-cells. These targets were further categorised and scored under three mechanistic classes/ therapeutic targets (postprandial hyperglycaemia; insulin resistance and inflammation; pancreatic β-cell function) to elucidate their potential mechanisms of action and select appropriate animal models for future studies. Almost any normal or diabetic rodent model would be suitable to explore the antidiabetic potential of extracts such as A. linearis, B. discolor ethanol, C. deliciosus ethanol or T. camphoratus which obtained high cumulative scores under postprandial hyperglycaemia while high fat diet and genetic models of obesity appear more suited towards extracts such as H. erinaceus aqueous that obtained their highest cumulative score under insulin resistance. In general, a combination of rodent models ranging from non-obese models to models of obesity and β-cell destruction presenting symptoms from all three mechanistic classes should be considered due to the pleiotropic nature of the tested extracts, however, establishing appropriate experimental designs is crucial. To demonstrate the versatility of the screening platform and emphasise the importance of in vitro screening pertaining to diabetic complications, a more detailed biochemical investigation into the potential therapeutic benefits of A. linearis in the treatment of diabetic wounds was conducted. Several properties supporting the therapeutic potential of rooibos were highlighted with the green and fermented extracts presenting distinctly different characteristics. The pro-inflammatory nature of fermented rooibos may have therapeutic value for wounds characterised with a delayed initial inflammatory phase, such as early diabetic wounds while the green extract appears more suited to wounds burdened with excessive inflammation as it attenuated COX-2 levels and effectively protected fibroblasts against oxidative stress. To date, this appears to be the most comprehensive antidiabetic screening platform in existence and consequently provides the only feasible solution that will enable natural product antidiabetic research to progress to the point where natural products can be commercialised and incorporated into meaningful healthcare programs. Future research should be focussed towards further expanding this model by incorporating additional targets, more sophisticated cell culturing techniques, multiplexed high content screening assays and carrying out combination treatments that explore the antidiabetic effects of two or more crude extracts to establish whether they are capable of acting in a synergistic manner.
- Full Text:
- Date Issued: 2020
- Authors: Pringle, Nadine Alex
- Date: 2020
- Subjects: Hypoglycemic agents
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/46750 , vital:39653
- Description: Several synthetic antidiabetic drugs have been developed to date, however, most are accompanied by adverse side-effects while remaining expensive and largely inaccessible to the vast majority of those who need it. To provide enough scientific evidence to support the inclusion of more affordable African antidiabetic medicinal plants and macrofungi into healthcare programs, this study sought out to develop a comprehensive in vitro antidiabetic target-directed screening platform incorporating high content screening and analysis/ cellomics. To test the success of this model, the potential antidiabetic mechanisms of five plants (Aspalathus linearis, Brachylaena discolor, Carpobrotus deliciosus, Sutherlandia frutescens and Tarchonanthus camphoratus) and two macrofungal species (Ganoderma lucidum and Hericium erinaceus) were explored. The screening model consisted of approximately 22 assays exploring the antidiabetic effects of selected aqueous and ethanolic extracts in five well-characterised antidiabetic targets: the intestine, liver, skeletal muscle, adipose tissue/ obesity and pancreatic β-cells. These targets were further categorised and scored under three mechanistic classes/ therapeutic targets (postprandial hyperglycaemia; insulin resistance and inflammation; pancreatic β-cell function) to elucidate their potential mechanisms of action and select appropriate animal models for future studies. Almost any normal or diabetic rodent model would be suitable to explore the antidiabetic potential of extracts such as A. linearis, B. discolor ethanol, C. deliciosus ethanol or T. camphoratus which obtained high cumulative scores under postprandial hyperglycaemia while high fat diet and genetic models of obesity appear more suited towards extracts such as H. erinaceus aqueous that obtained their highest cumulative score under insulin resistance. In general, a combination of rodent models ranging from non-obese models to models of obesity and β-cell destruction presenting symptoms from all three mechanistic classes should be considered due to the pleiotropic nature of the tested extracts, however, establishing appropriate experimental designs is crucial. To demonstrate the versatility of the screening platform and emphasise the importance of in vitro screening pertaining to diabetic complications, a more detailed biochemical investigation into the potential therapeutic benefits of A. linearis in the treatment of diabetic wounds was conducted. Several properties supporting the therapeutic potential of rooibos were highlighted with the green and fermented extracts presenting distinctly different characteristics. The pro-inflammatory nature of fermented rooibos may have therapeutic value for wounds characterised with a delayed initial inflammatory phase, such as early diabetic wounds while the green extract appears more suited to wounds burdened with excessive inflammation as it attenuated COX-2 levels and effectively protected fibroblasts against oxidative stress. To date, this appears to be the most comprehensive antidiabetic screening platform in existence and consequently provides the only feasible solution that will enable natural product antidiabetic research to progress to the point where natural products can be commercialised and incorporated into meaningful healthcare programs. Future research should be focussed towards further expanding this model by incorporating additional targets, more sophisticated cell culturing techniques, multiplexed high content screening assays and carrying out combination treatments that explore the antidiabetic effects of two or more crude extracts to establish whether they are capable of acting in a synergistic manner.
- Full Text:
- Date Issued: 2020
Computer aided approaches against Human African Trypanosomiasis
- Authors: Kimuda, Magambo Phillip
- Date: 2020
- Subjects: African trypanosomiasis , African trypanosomiasis -- Chemotherapy , Genomics , Macrophage migration inhibitory factor , Trypanosoma brucei , Pteridines , Tetrahydrofolate dehydrogenase , Adenylic acid , Molecular dynamics , Principal components analysis , Bioinformatics , Single nucleotide polymorphisms , Single Nucleotide Variants , Candidate Gene Association Study (CGAS)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142542 , vital:38089
- Description: The thesis presented here is divided into two parts under a common theme that is the use of computer based tools, genomics, and in vitro experiments to develop innovative ways of tackling Human African Trypanosomiasis (HAT). Part I of this thesis focused on the human host genetic determinants while Part II focused on the discovery of novel chemotherapeutics against the parasite. Part I is further sub-divided into two parts: The first involves a Candidate Gene Association Study (CGAS) on an African population to identify genetic determinants associated with disease and/or susceptibility to HAT. The second involves studying the effects of missense Single Nucleotide Variants (SNVs) on protein structure, dynamics, and function using Macrophage Migration Inhibitory Factor (MIF) as a case study. Part II is also sub-divided into two parts: The first involves a computer based rational drug discovery of potential inhibitors against the Trypanosoma the folate pathway; particularly by targeting Trypanosoma brucei Pteridine Reductase (TbPTR1) which is an enzyme used by trypanosomes to overcome T. brucei Dihydrofolate Reductase (TbDHFR) inhibition. Lastly the derivation of CHARMM force-field parameters that can be used to accurately model the geometry and dynamics of the T. brucei Phosphodiesterase B1 enzyme (TbrPDEB1) bimetallic active site center. The derived parameters were then used in MD simulations to characterise protein-ligand residue interactions that are important in TbrPDEB1 inhibition with the goal of targeting the cyclic Adenosine Monophosphate (cAMP) signalling pathway. In the CGAS we were unable to detect any genetic associations in the Ugandan cohort analysed that passed correction for multiple testing in spite of the study being sufficiently powered. Additionally, our study found no association of the Apo lipoprotein 1 (APOL1) G2 allele association with protection against acute HAT that has been previously reported. Future investigations for example, Genome Wide Association Studies using larger samples sizes (>3000 cases and controls) are required. Macrophage migration inhibitory factor (MIF) is a cytokine that is important in both innate and adaptive immunity that has been shown to play a role in T. brucei pathogenicity using murine models. A total of 27 missense SNVs were modelled using homology modelling to create MIF protein mutants that were investigated using in silico effect prediction tools, molecular dynamics (MD), Principal Component Analysis (PCA), and Dynamic Residue Network (DRN) analysis. Our results demonstrate that mutations P2Q, I5M, P16Q, L23F, T24S, T31I, Y37H, H41P, M48V, P44L, G52C, S54R, I65M, I68T, S75F, N106S, and T113S caused significant conformational changes. Further, DRN analysis showed that residues P2, T31, Y37, G52, I65, I68, S75, N106, and T113S are part of a similar local residue interaction network with functional significance. These results show how polymorphisms such as missense SNVs can affect protein conformation, dynamics, and function. Trypanosomes are auxotrophic for folates and pterins but require them for survival. They scavenge them from their hosts. PTR1 is a multifunctional enzyme that is unique to trypanosomatids that reduces both pterins and folates. In the presence of DHFR inhibitors, PTR1 is over-expressed thus providing an escape from the effects of DHFR inhibition. Both TbPTR1 and TbDHFR are pharmacologically and genetically validated drug targets. In this study 5742 compounds were screened using molecular docking, and 13 promising binding modes were further analysed using MD simulations. The trajectories were analysed using RMSD, Rg, RMSF, PCA, Essential Dynamics Analysis (EDA), Molecular Mechanics Poisson–Boltzmann surface area (MM-PBSA) binding free energy calculations, and DRN analysis. The computational screening approach allowed us to identify five of the compounds, named RUBi004, RUBi007, RUBi014, RUBi016 and RUBi018 that exhibited antitrypanosomal growth activities against trypanosomes in culture with IC50 values of 12.5 ± 4.8 μM, 32.4 ± 4.2 μM, 5.9 ± 1.4 μM, 28.2 ± 3.3 μM, and 9.7 ± 2.1 μM, respectively. Further when used in combination with WR99210 a known TbDHFR inhibitor RUBi004, RUBi007, RUBi014 and RUBi018 showed antagonism while RUBi016 showed an additive effect. These results indicate that the four compounds might be competing with TbDHFR while RUBi016 might be more specific for TbPTR1. These compounds provide scaffolds that can be further optimised to improve their potency and specificity. Lastly, using a systematic approach we derived CHARMM force-field parameters to accurately describe the TbrPDEB1 bi-metal catalytic center. For dynamics, we employed mixed bonded and non-bonded approach. We optimised the structure using a two-layer QM/MM ONIOM (B3LYP/6-31(g): UFF). The TbrPDEB1 bi-metallic center bonds, angles, and dihedrals were parameterized by fitting the energy profiles from Potential Energy Surface (PES) scans to the CHARMM potential energy function. The parameters were validated by means of MD simulations and analysed using RMSD, Rg, RMSF, hydrogen bonding, bond/angle/dihedral evaluations, EDA, PCA, and DRN analysis. The force-field parameters were able to accurately reproduce the geometry and dynamics of the TbrPDEB1 bi-metal catalytic center during MD simulations. Molecular docking was used to identify 6 potential hits, that inhibited trypanosome growth in vitro. The derived force-field parameters were used to simulate the 6 protein-ligand complexes with the aim of elucidating crucial protein-ligand residue interactions. Using the most potent ligand RUBi022 that had an IC50 of 14.96 μM we were able to identify key residue interactions that can be of use in in silico prediction of potential TbrPDEB1 inhibitors. Overall we demonstrate how bioinformatics tools can complement current disease eradication strategies. Future work will focus on identifying variants identified in Genome Wide Association Studies and partnering with wet labs to carry out further enzyme-ligand activity relationship studies, structure determination or characterisation of appropriate protein-ligand complexes by crystallography, and site specific mutation studies
- Full Text:
- Date Issued: 2020
- Authors: Kimuda, Magambo Phillip
- Date: 2020
- Subjects: African trypanosomiasis , African trypanosomiasis -- Chemotherapy , Genomics , Macrophage migration inhibitory factor , Trypanosoma brucei , Pteridines , Tetrahydrofolate dehydrogenase , Adenylic acid , Molecular dynamics , Principal components analysis , Bioinformatics , Single nucleotide polymorphisms , Single Nucleotide Variants , Candidate Gene Association Study (CGAS)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142542 , vital:38089
- Description: The thesis presented here is divided into two parts under a common theme that is the use of computer based tools, genomics, and in vitro experiments to develop innovative ways of tackling Human African Trypanosomiasis (HAT). Part I of this thesis focused on the human host genetic determinants while Part II focused on the discovery of novel chemotherapeutics against the parasite. Part I is further sub-divided into two parts: The first involves a Candidate Gene Association Study (CGAS) on an African population to identify genetic determinants associated with disease and/or susceptibility to HAT. The second involves studying the effects of missense Single Nucleotide Variants (SNVs) on protein structure, dynamics, and function using Macrophage Migration Inhibitory Factor (MIF) as a case study. Part II is also sub-divided into two parts: The first involves a computer based rational drug discovery of potential inhibitors against the Trypanosoma the folate pathway; particularly by targeting Trypanosoma brucei Pteridine Reductase (TbPTR1) which is an enzyme used by trypanosomes to overcome T. brucei Dihydrofolate Reductase (TbDHFR) inhibition. Lastly the derivation of CHARMM force-field parameters that can be used to accurately model the geometry and dynamics of the T. brucei Phosphodiesterase B1 enzyme (TbrPDEB1) bimetallic active site center. The derived parameters were then used in MD simulations to characterise protein-ligand residue interactions that are important in TbrPDEB1 inhibition with the goal of targeting the cyclic Adenosine Monophosphate (cAMP) signalling pathway. In the CGAS we were unable to detect any genetic associations in the Ugandan cohort analysed that passed correction for multiple testing in spite of the study being sufficiently powered. Additionally, our study found no association of the Apo lipoprotein 1 (APOL1) G2 allele association with protection against acute HAT that has been previously reported. Future investigations for example, Genome Wide Association Studies using larger samples sizes (>3000 cases and controls) are required. Macrophage migration inhibitory factor (MIF) is a cytokine that is important in both innate and adaptive immunity that has been shown to play a role in T. brucei pathogenicity using murine models. A total of 27 missense SNVs were modelled using homology modelling to create MIF protein mutants that were investigated using in silico effect prediction tools, molecular dynamics (MD), Principal Component Analysis (PCA), and Dynamic Residue Network (DRN) analysis. Our results demonstrate that mutations P2Q, I5M, P16Q, L23F, T24S, T31I, Y37H, H41P, M48V, P44L, G52C, S54R, I65M, I68T, S75F, N106S, and T113S caused significant conformational changes. Further, DRN analysis showed that residues P2, T31, Y37, G52, I65, I68, S75, N106, and T113S are part of a similar local residue interaction network with functional significance. These results show how polymorphisms such as missense SNVs can affect protein conformation, dynamics, and function. Trypanosomes are auxotrophic for folates and pterins but require them for survival. They scavenge them from their hosts. PTR1 is a multifunctional enzyme that is unique to trypanosomatids that reduces both pterins and folates. In the presence of DHFR inhibitors, PTR1 is over-expressed thus providing an escape from the effects of DHFR inhibition. Both TbPTR1 and TbDHFR are pharmacologically and genetically validated drug targets. In this study 5742 compounds were screened using molecular docking, and 13 promising binding modes were further analysed using MD simulations. The trajectories were analysed using RMSD, Rg, RMSF, PCA, Essential Dynamics Analysis (EDA), Molecular Mechanics Poisson–Boltzmann surface area (MM-PBSA) binding free energy calculations, and DRN analysis. The computational screening approach allowed us to identify five of the compounds, named RUBi004, RUBi007, RUBi014, RUBi016 and RUBi018 that exhibited antitrypanosomal growth activities against trypanosomes in culture with IC50 values of 12.5 ± 4.8 μM, 32.4 ± 4.2 μM, 5.9 ± 1.4 μM, 28.2 ± 3.3 μM, and 9.7 ± 2.1 μM, respectively. Further when used in combination with WR99210 a known TbDHFR inhibitor RUBi004, RUBi007, RUBi014 and RUBi018 showed antagonism while RUBi016 showed an additive effect. These results indicate that the four compounds might be competing with TbDHFR while RUBi016 might be more specific for TbPTR1. These compounds provide scaffolds that can be further optimised to improve their potency and specificity. Lastly, using a systematic approach we derived CHARMM force-field parameters to accurately describe the TbrPDEB1 bi-metal catalytic center. For dynamics, we employed mixed bonded and non-bonded approach. We optimised the structure using a two-layer QM/MM ONIOM (B3LYP/6-31(g): UFF). The TbrPDEB1 bi-metallic center bonds, angles, and dihedrals were parameterized by fitting the energy profiles from Potential Energy Surface (PES) scans to the CHARMM potential energy function. The parameters were validated by means of MD simulations and analysed using RMSD, Rg, RMSF, hydrogen bonding, bond/angle/dihedral evaluations, EDA, PCA, and DRN analysis. The force-field parameters were able to accurately reproduce the geometry and dynamics of the TbrPDEB1 bi-metal catalytic center during MD simulations. Molecular docking was used to identify 6 potential hits, that inhibited trypanosome growth in vitro. The derived force-field parameters were used to simulate the 6 protein-ligand complexes with the aim of elucidating crucial protein-ligand residue interactions. Using the most potent ligand RUBi022 that had an IC50 of 14.96 μM we were able to identify key residue interactions that can be of use in in silico prediction of potential TbrPDEB1 inhibitors. Overall we demonstrate how bioinformatics tools can complement current disease eradication strategies. Future work will focus on identifying variants identified in Genome Wide Association Studies and partnering with wet labs to carry out further enzyme-ligand activity relationship studies, structure determination or characterisation of appropriate protein-ligand complexes by crystallography, and site specific mutation studies
- Full Text:
- Date Issued: 2020
Conceptualisations of and responses to plagiarism in the South African higher education system
- Mphahlele, Martha Matee (Amanda)
- Authors: Mphahlele, Martha Matee (Amanda)
- Date: 2020
- Subjects: Plagiarism , Plagiarism -- Prevention -- South Africa , Education, Higher -- Moral and ethical aspects , Education, Higher -- South Africa , Cheating (Education) -- South Africa , College students -- Legal status, laws, etc. -- South Africa , College discipline -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/162642 , vital:40963
- Description: Violations of academic integrity are a cause for concern in universities around the world and plagiarism is one of the most significant examples of these academic integrity issues with which universities are grappling . The approach taken to managing plagiarism depends to a large extent on the understanding of the phenomenon within institutions. This study investigated how plagiarism is conceptualised and responded to in the South African Higher Education system and how this impacts on teaching and learning. Data was collected from 25 out of the 26 South African public universities; the missing university had just been established and did not yet have policies or processes in place. The data was primarily in the form of documents known in these institutions as ‘plagiarism policies’, along with a wealth of other related policies and reports. This was supplemented by interviews as a means of verifying the document analysis with seven plagiarism committee members from across the three institutional types in South Africa, namely: traditional universities, comprehensive universities, and universities of technology. Using Bhaskar’s (2008) critical realism as a metatheory and Archer’s (1995) social realism as both a substantive theory and analytical framework, the experiences and events of plagiarism management were critically examined. Critical realism consider s these experiences and events at the level of the e mpirical and the actual , in order to identify the mechanisms at the l evel of the r eal from which these emerge. Social realism argues that when undertaking such an analysis in the social world, this entails identifying the emergent properties of both the parts (structure and culture) and people (agents). Therefore, the data was analysed using Archer’s analytical dualism to identify structural, cultural and agential mechanisms shaping the understanding of plagiarism and the practices associated with managing the phenomenon. The study found that dominant in the sector was an un derstanding of plagiarism as always being an intentional act, with implications for teaching and learning practices, which then focused on identifying and punishing incidents of plagiarism in student writing. A legal discourse was found to permeate the universities’ plagiarism management systems, such that most procedures replicated the legal framework. This was seen to undermine the identity of universities as teaching and learning spaces and of students as novice members of the disciplinary fields. The study further highlighted that due to plagiarism being perceived as an intentional act, punishment in almost all universities is prioritised as the key means of attending to plagiarism in the se institutions. This emerged as a structural constraint to students’ acquisition of academic writing norms. Such understandings and approaches were seen to be complementary to the risk-aversion of many institutions in a globalised era of university rankings. As increased bureaucracy has been put in place to attend to incidents of plagiarism, including obligatory reporting thereof, an unintentional consequence emerged, where it was at times simpler for academics to ignore incidences of plagiarism than to act on them. Turnitin was frequently referred to across the data as the preferred text - matching tool, but Turnitin together with other text-matching tools , was often used in a way that complemented the understanding of plagiarism as always being an intentional act. The stu dy found that text - matching software was largely misunderstood to be plagiarism software, where the similarity index was perceived to be a measure of plagiarism. This led to an understanding that students needed to paraphrase texts in order to avoid detect ion by the program me, and this may inadvertently encourage plagiarism , as students are taught to write towards the software. The research found that in those instances where educational responses to plagiarism were in place, they often demonstrated a lack of understanding of academic literacies development and the extent to which norms of knowledge production are disciplinary specific. Most (but not all) of the data about educational responses focused on add-on workshops and the signing of a declaration form, indicating that the student has not plagiarised. The workshops were seen to emphasise technical skills, such as the punctuation norms of referencing, and were often offered in a generic format by people outside of the target disciplines. These workshops were found to ignore the connection between the technical skills of referencing and the norms of knowledge construction, with a potential deleterious effect on the development of authorial identity. Finally, the data showed a few instances where particular institutions acknowledged that plagiarism occurs along a continuum, where on one side is intentional plagiarism associated with cheating and requiring punishment, and on the other side is unintentional plagiarism, which is understood to require an educational response , and was seen to emerge from either a lack of understanding of academic literacy norms , or from negligence. Literacy development with regard to taking on the norms of knowledge-making in the academy was seen to be a complex and lengthy process that was fundamental to educational endeavours of facilitating epistemological access, while cases of negligence were seen to be mainly caused by technical oversight rather than a lack of access to the relevant knowledge production norms. The study concludes by arguing that cases of intentional plagiarism require quick and appropriate punishment, but that there also needs to be an institution-wide understanding that unintentional plagiarism often emerges from students failing to access the specific knowledge-making norms of the discipline. There is thus a need for academics to be aware of the complexities related to taking on literacy practices, and who also understand the role of feedback in this process. But it ought not to be assumed that academics would have such insights simply by virtue of their expertise in the discipline. These academics need to have carefully constructed staff development support, as they take on such pedagogical approaches. The study argues that the dominant conceptualisation of plagiarism in the domain of culture as an intentional act and the complementary policies and processes in the domain of structure as focusing on detecting and punishing incidents of plagiarism, fail to address plagiarism in appropriate educational ways.
- Full Text:
- Date Issued: 2020
- Authors: Mphahlele, Martha Matee (Amanda)
- Date: 2020
- Subjects: Plagiarism , Plagiarism -- Prevention -- South Africa , Education, Higher -- Moral and ethical aspects , Education, Higher -- South Africa , Cheating (Education) -- South Africa , College students -- Legal status, laws, etc. -- South Africa , College discipline -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/162642 , vital:40963
- Description: Violations of academic integrity are a cause for concern in universities around the world and plagiarism is one of the most significant examples of these academic integrity issues with which universities are grappling . The approach taken to managing plagiarism depends to a large extent on the understanding of the phenomenon within institutions. This study investigated how plagiarism is conceptualised and responded to in the South African Higher Education system and how this impacts on teaching and learning. Data was collected from 25 out of the 26 South African public universities; the missing university had just been established and did not yet have policies or processes in place. The data was primarily in the form of documents known in these institutions as ‘plagiarism policies’, along with a wealth of other related policies and reports. This was supplemented by interviews as a means of verifying the document analysis with seven plagiarism committee members from across the three institutional types in South Africa, namely: traditional universities, comprehensive universities, and universities of technology. Using Bhaskar’s (2008) critical realism as a metatheory and Archer’s (1995) social realism as both a substantive theory and analytical framework, the experiences and events of plagiarism management were critically examined. Critical realism consider s these experiences and events at the level of the e mpirical and the actual , in order to identify the mechanisms at the l evel of the r eal from which these emerge. Social realism argues that when undertaking such an analysis in the social world, this entails identifying the emergent properties of both the parts (structure and culture) and people (agents). Therefore, the data was analysed using Archer’s analytical dualism to identify structural, cultural and agential mechanisms shaping the understanding of plagiarism and the practices associated with managing the phenomenon. The study found that dominant in the sector was an un derstanding of plagiarism as always being an intentional act, with implications for teaching and learning practices, which then focused on identifying and punishing incidents of plagiarism in student writing. A legal discourse was found to permeate the universities’ plagiarism management systems, such that most procedures replicated the legal framework. This was seen to undermine the identity of universities as teaching and learning spaces and of students as novice members of the disciplinary fields. The study further highlighted that due to plagiarism being perceived as an intentional act, punishment in almost all universities is prioritised as the key means of attending to plagiarism in the se institutions. This emerged as a structural constraint to students’ acquisition of academic writing norms. Such understandings and approaches were seen to be complementary to the risk-aversion of many institutions in a globalised era of university rankings. As increased bureaucracy has been put in place to attend to incidents of plagiarism, including obligatory reporting thereof, an unintentional consequence emerged, where it was at times simpler for academics to ignore incidences of plagiarism than to act on them. Turnitin was frequently referred to across the data as the preferred text - matching tool, but Turnitin together with other text-matching tools , was often used in a way that complemented the understanding of plagiarism as always being an intentional act. The stu dy found that text - matching software was largely misunderstood to be plagiarism software, where the similarity index was perceived to be a measure of plagiarism. This led to an understanding that students needed to paraphrase texts in order to avoid detect ion by the program me, and this may inadvertently encourage plagiarism , as students are taught to write towards the software. The research found that in those instances where educational responses to plagiarism were in place, they often demonstrated a lack of understanding of academic literacies development and the extent to which norms of knowledge production are disciplinary specific. Most (but not all) of the data about educational responses focused on add-on workshops and the signing of a declaration form, indicating that the student has not plagiarised. The workshops were seen to emphasise technical skills, such as the punctuation norms of referencing, and were often offered in a generic format by people outside of the target disciplines. These workshops were found to ignore the connection between the technical skills of referencing and the norms of knowledge construction, with a potential deleterious effect on the development of authorial identity. Finally, the data showed a few instances where particular institutions acknowledged that plagiarism occurs along a continuum, where on one side is intentional plagiarism associated with cheating and requiring punishment, and on the other side is unintentional plagiarism, which is understood to require an educational response , and was seen to emerge from either a lack of understanding of academic literacy norms , or from negligence. Literacy development with regard to taking on the norms of knowledge-making in the academy was seen to be a complex and lengthy process that was fundamental to educational endeavours of facilitating epistemological access, while cases of negligence were seen to be mainly caused by technical oversight rather than a lack of access to the relevant knowledge production norms. The study concludes by arguing that cases of intentional plagiarism require quick and appropriate punishment, but that there also needs to be an institution-wide understanding that unintentional plagiarism often emerges from students failing to access the specific knowledge-making norms of the discipline. There is thus a need for academics to be aware of the complexities related to taking on literacy practices, and who also understand the role of feedback in this process. But it ought not to be assumed that academics would have such insights simply by virtue of their expertise in the discipline. These academics need to have carefully constructed staff development support, as they take on such pedagogical approaches. The study argues that the dominant conceptualisation of plagiarism in the domain of culture as an intentional act and the complementary policies and processes in the domain of structure as focusing on detecting and punishing incidents of plagiarism, fail to address plagiarism in appropriate educational ways.
- Full Text:
- Date Issued: 2020
Conceptualising community radio: from global histories to the Kenyan example
- Authors: Korir, Geoffrey Kiplimo
- Date: 2020
- Subjects: Community radio , Community radio -- Kenya , Community development -- Kenya , Social change -- Kenya , Radio broadcasting -- Kenya
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/165766 , vital:41279
- Description: This study sets out to gain insight into the way that the establishment of community radio in Kenya is located within the global history of ideas about such radio. The first four chapters in this study provide terms of reference for this examination through a series of literature reviews. It sets out, firstly, to locate the internationally shared conceptualisaiton of community radio within an existing spectrum of approaches to social analysis. It proposes that community radio can be located at the critical, emancipatory end of this spectrum. It then maps out the global circulation of ideas about community radio and proposes that such circulation was informed by the broader history of critical, emancipatory social analysis. The final literature review then deals with community radio in Kenya and examines the way in which the establishment of this sector was shaped by the social and political history of this country. It is argued that the establishment of a community radio sector became possible only when support for emancipatory approaches to media became acceptable in Kenya, in context of the establishment of multiparty democracy. It is proposed, further, that the articulation of a vision for community radio in Kenya depended in part on the existence of international support for such radio and in part on the efforts of local actors in civil society. The empirical component then focuses on the way global ideas about community radio have become realised in Kenya. The study achieves this purpose by drawing on qualitative interviews with individuals from within civil society who have participated in the history of the establishment and growth of community radio in Kenya. These individuals demonstrate consciousness of the internationally shared set of principles that can facilitate a successful establishment of community radio. However, they are also sceptical of the assumption that guidelines for community radio are universally applicable. They point, in particular, to the challenges involved in the realisation of these guidelines in an environment in which economic resources are limited, and which is characterised by extreme social inequality and conflict. The study concludes that it is individuals such as these participants, who are embedded within the local context, who are best placed to articulate locally appropriate alternatives to these guidelines.
- Full Text:
- Date Issued: 2020
- Authors: Korir, Geoffrey Kiplimo
- Date: 2020
- Subjects: Community radio , Community radio -- Kenya , Community development -- Kenya , Social change -- Kenya , Radio broadcasting -- Kenya
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/165766 , vital:41279
- Description: This study sets out to gain insight into the way that the establishment of community radio in Kenya is located within the global history of ideas about such radio. The first four chapters in this study provide terms of reference for this examination through a series of literature reviews. It sets out, firstly, to locate the internationally shared conceptualisaiton of community radio within an existing spectrum of approaches to social analysis. It proposes that community radio can be located at the critical, emancipatory end of this spectrum. It then maps out the global circulation of ideas about community radio and proposes that such circulation was informed by the broader history of critical, emancipatory social analysis. The final literature review then deals with community radio in Kenya and examines the way in which the establishment of this sector was shaped by the social and political history of this country. It is argued that the establishment of a community radio sector became possible only when support for emancipatory approaches to media became acceptable in Kenya, in context of the establishment of multiparty democracy. It is proposed, further, that the articulation of a vision for community radio in Kenya depended in part on the existence of international support for such radio and in part on the efforts of local actors in civil society. The empirical component then focuses on the way global ideas about community radio have become realised in Kenya. The study achieves this purpose by drawing on qualitative interviews with individuals from within civil society who have participated in the history of the establishment and growth of community radio in Kenya. These individuals demonstrate consciousness of the internationally shared set of principles that can facilitate a successful establishment of community radio. However, they are also sceptical of the assumption that guidelines for community radio are universally applicable. They point, in particular, to the challenges involved in the realisation of these guidelines in an environment in which economic resources are limited, and which is characterised by extreme social inequality and conflict. The study concludes that it is individuals such as these participants, who are embedded within the local context, who are best placed to articulate locally appropriate alternatives to these guidelines.
- Full Text:
- Date Issued: 2020
Conflict related sexual violence against males:recognition by and responses of humanitarian organizations in Africa
- Authors: Akurut, Catherine
- Date: 2020
- Subjects: Male rape victims -- Africa , Gender in conflict management --Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/46648 , vital:39605
- Description: The study investigated the knowledge, attitudes, and experiences of humanitarian service providers concerning the recognition of and response to the phenomenon of male victims of conflict-related sexual violence against males. Sources of literature in respect to the awareness, understanding, and recognition of conflict-related sexual violence against males were explored. Perceptions about the recognition of male victims were discovered. Response strategies available to male victims were explored through the experiences of humanitarian organisation representatives, including, inter alia, programme managers, gender-based violence advisers, protection officers and activists. Mechanisms to augment any existing practices to allow for the care of and support for male victims were examined. A qualitative research approach was used to explore the topic of this study. Data was collected using semi-structured interview questions that were developed. And document review was also used as the second means of data collection. The research participants were recruited using purposive sampling, which was complemented by snowballing until data saturation. Triangulation was used by combining the two data collection methods to avoid relying on one source. A narrative literature review was aimed to obtain further information about the phenomenon of conflict-related sexual violence against males.
- Full Text:
- Date Issued: 2020
- Authors: Akurut, Catherine
- Date: 2020
- Subjects: Male rape victims -- Africa , Gender in conflict management --Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/46648 , vital:39605
- Description: The study investigated the knowledge, attitudes, and experiences of humanitarian service providers concerning the recognition of and response to the phenomenon of male victims of conflict-related sexual violence against males. Sources of literature in respect to the awareness, understanding, and recognition of conflict-related sexual violence against males were explored. Perceptions about the recognition of male victims were discovered. Response strategies available to male victims were explored through the experiences of humanitarian organisation representatives, including, inter alia, programme managers, gender-based violence advisers, protection officers and activists. Mechanisms to augment any existing practices to allow for the care of and support for male victims were examined. A qualitative research approach was used to explore the topic of this study. Data was collected using semi-structured interview questions that were developed. And document review was also used as the second means of data collection. The research participants were recruited using purposive sampling, which was complemented by snowballing until data saturation. Triangulation was used by combining the two data collection methods to avoid relying on one source. A narrative literature review was aimed to obtain further information about the phenomenon of conflict-related sexual violence against males.
- Full Text:
- Date Issued: 2020
Conservation biology of an apex predator in the Anthropocene : poaching, pastoralism and lions in multi-use landscapes, South-Eastern Africa
- Authors: Everatt, Kristoffer T
- Date: 2020
- Subjects: Conservation biology -- Africa, Southern
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/48290 , vital:40839
- Description: Many of the world’s apex predators are experiencing catastrophic declines as a result of competition with humans. Understanding the mechanisms and ecosystem impacts of apex predator declines is a fundamental ecological question crucial to conserving the Earth’s biodiversity and functioning ecosystems. In this thesis I used the African lion Panthera leo, as a model species to investigate the impacts of anthropogenic pressures on the conservation and ecology of an apex predator. Specifically, I investigated the relative and cumulative influences of pastoralism and poaching on lion occurrence, population connectivity, ecological role, space use, prey selection and viability across a 73 000 km2 multi-use landscape in southern Africa. Using landscape occupancy spoor surveys, I tested the hypotheses that lions were most limited by either interference or by exploitative competition with humans and identified thresholds of lion tolerance to human activities. My results showed that lions occupied only a fraction of the landscape and were limited by a combination of interference and exploitative competition with humans. Interference competition with pastoralism however was the biggest driver limiting lion occupancy, creating a clear disturbance threshold for lions cumulating in their near complete loss from the landscape. I employed call-up surveys, pride monitoring and mortality analysis to investigate the numerical impacts of anthropogenic pressures on the viability of a lion sub-population. I found that persecution by pastoralists was the greatest source of lion mortalities across the landscape. However, the targeted poaching of lions for body parts had emerged as the greatest threat to lions in a nominally protected National Park where I documented a steep population decline and collapse of lion prides. I used GPS tracking and diet analysis of lions at the human-wildlands interface to test if lions foraged optimally or were constrained by competition with humans. I fount that individual lions appeared to select for prey and habitat optimally, while also showing some level of risk avoidance towards anthropogenic pressures. I then considered landscape resistances to test if sink habitats may provide connectivity between sources or act as ecological traps. I found that potential connectivity for lions between the region’s two source populations was limited by a loss of habitat and prey. Furthermore, the impacts of by-catch in snares risked transforming the few remaining potential conservation corridors into ecological traps. Finally, I examined interactions between lions and syntopic mesopredators across gradients of anthropogenic pressures to test if the functional role of lions was affected by human pressures. I found that lions showed limited suppression of mesopredators, however, anthropogenic pressures increased lion’s interactions with syntopic predators. As an apex predator, lions have evolved limited capacity to mitigate top-down competitive pressures, however, like many of the world’s apex predators, they are becoming increasingly limited by anthropogenic pressures. This study provides a predictive understanding of an apex predator’s ecological responses to top-down anthropogenic pressures which can be applied globally to the question of conservation in the Anthropocene.
- Full Text:
- Date Issued: 2020
- Authors: Everatt, Kristoffer T
- Date: 2020
- Subjects: Conservation biology -- Africa, Southern
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/48290 , vital:40839
- Description: Many of the world’s apex predators are experiencing catastrophic declines as a result of competition with humans. Understanding the mechanisms and ecosystem impacts of apex predator declines is a fundamental ecological question crucial to conserving the Earth’s biodiversity and functioning ecosystems. In this thesis I used the African lion Panthera leo, as a model species to investigate the impacts of anthropogenic pressures on the conservation and ecology of an apex predator. Specifically, I investigated the relative and cumulative influences of pastoralism and poaching on lion occurrence, population connectivity, ecological role, space use, prey selection and viability across a 73 000 km2 multi-use landscape in southern Africa. Using landscape occupancy spoor surveys, I tested the hypotheses that lions were most limited by either interference or by exploitative competition with humans and identified thresholds of lion tolerance to human activities. My results showed that lions occupied only a fraction of the landscape and were limited by a combination of interference and exploitative competition with humans. Interference competition with pastoralism however was the biggest driver limiting lion occupancy, creating a clear disturbance threshold for lions cumulating in their near complete loss from the landscape. I employed call-up surveys, pride monitoring and mortality analysis to investigate the numerical impacts of anthropogenic pressures on the viability of a lion sub-population. I found that persecution by pastoralists was the greatest source of lion mortalities across the landscape. However, the targeted poaching of lions for body parts had emerged as the greatest threat to lions in a nominally protected National Park where I documented a steep population decline and collapse of lion prides. I used GPS tracking and diet analysis of lions at the human-wildlands interface to test if lions foraged optimally or were constrained by competition with humans. I fount that individual lions appeared to select for prey and habitat optimally, while also showing some level of risk avoidance towards anthropogenic pressures. I then considered landscape resistances to test if sink habitats may provide connectivity between sources or act as ecological traps. I found that potential connectivity for lions between the region’s two source populations was limited by a loss of habitat and prey. Furthermore, the impacts of by-catch in snares risked transforming the few remaining potential conservation corridors into ecological traps. Finally, I examined interactions between lions and syntopic mesopredators across gradients of anthropogenic pressures to test if the functional role of lions was affected by human pressures. I found that lions showed limited suppression of mesopredators, however, anthropogenic pressures increased lion’s interactions with syntopic predators. As an apex predator, lions have evolved limited capacity to mitigate top-down competitive pressures, however, like many of the world’s apex predators, they are becoming increasingly limited by anthropogenic pressures. This study provides a predictive understanding of an apex predator’s ecological responses to top-down anthropogenic pressures which can be applied globally to the question of conservation in the Anthropocene.
- Full Text:
- Date Issued: 2020
Conserving land for people: transformative adaptive co-management of sustainable protected areas in the eastern Democratic Republic of Congo
- Authors: Kalyongo, Kujirakwinja Deo
- Date: 2020
- Subjects: Protected areas -- Congo (Democratic Republic) , Protected areas -- Government policy -- Congo (Democratic Republic) , Protected areas -- Management -- Congo (Democratic Republic) , Conservation of natural resources -- Congo (Democratic Republic)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/165912 , vital:41296
- Description: Conservation practices and approaches in the Democratic Republic of Congo (DRC), as in other parts of the world, have evolved from traditional to fortress and collaborative contemporary approaches such as adaptive co-management. These approaches aim to include multiple decision-makers using diversified resources and, existing formal and informal governance structures. Collaborative approaches also consider conflict resolution and external factors that can influence conservation outputs and outcomes. In the DRC context, conflicts over resources are related not only to resource access and power but also to the ineffectiveness of collaborative approaches that exclude stakeholders such as local communities. These conflicts have negatively affected protected areas and weakened the management and governance of protected areas. Therefore, evolving approaches such as adaptive co-management that consider power relations, the multi-scaled involvement of actors and learning loops to adjust strategies are seen as better options to improve the governance of protected areas and minimise the degradation of key ecosystems. My research explored the gazettement processes of three protected areas in the eastern DRC (Itombwe, Kabobo and Okapi Reserves). I focused on the influence of social-political, historical and psychological factors on the management and governance of protected areas in the DRC. In addition, the research reveals the inclusive gazettement processes of protected areas is the foundation of successful co-management approaches. I found that values and good governance practices play a key role in influencing local perceptions and support to conservation interventions. Whilst some conservation practitioners believe that economic benefits to communities are the most predominant motivating factor, I found that good conservation management practices can motivate communities to support protected area management. Bad management practices were related not only to inadequate conservation approaches and practices but also to factors such as corruption, inadequate law enforcement and the inappropriate equipment of rangers. Therefore, I suggest that long term protected area management in DRC should consider how the value of resources for communities and protected areas have been changing throughout the history of conservation, and how to best share power and responsibilities with local resource users and stakeholders. This is only possible if conservation practices and approaches, governance process and institutions are transformed at multiple levels.
- Full Text:
- Date Issued: 2020
- Authors: Kalyongo, Kujirakwinja Deo
- Date: 2020
- Subjects: Protected areas -- Congo (Democratic Republic) , Protected areas -- Government policy -- Congo (Democratic Republic) , Protected areas -- Management -- Congo (Democratic Republic) , Conservation of natural resources -- Congo (Democratic Republic)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/165912 , vital:41296
- Description: Conservation practices and approaches in the Democratic Republic of Congo (DRC), as in other parts of the world, have evolved from traditional to fortress and collaborative contemporary approaches such as adaptive co-management. These approaches aim to include multiple decision-makers using diversified resources and, existing formal and informal governance structures. Collaborative approaches also consider conflict resolution and external factors that can influence conservation outputs and outcomes. In the DRC context, conflicts over resources are related not only to resource access and power but also to the ineffectiveness of collaborative approaches that exclude stakeholders such as local communities. These conflicts have negatively affected protected areas and weakened the management and governance of protected areas. Therefore, evolving approaches such as adaptive co-management that consider power relations, the multi-scaled involvement of actors and learning loops to adjust strategies are seen as better options to improve the governance of protected areas and minimise the degradation of key ecosystems. My research explored the gazettement processes of three protected areas in the eastern DRC (Itombwe, Kabobo and Okapi Reserves). I focused on the influence of social-political, historical and psychological factors on the management and governance of protected areas in the DRC. In addition, the research reveals the inclusive gazettement processes of protected areas is the foundation of successful co-management approaches. I found that values and good governance practices play a key role in influencing local perceptions and support to conservation interventions. Whilst some conservation practitioners believe that economic benefits to communities are the most predominant motivating factor, I found that good conservation management practices can motivate communities to support protected area management. Bad management practices were related not only to inadequate conservation approaches and practices but also to factors such as corruption, inadequate law enforcement and the inappropriate equipment of rangers. Therefore, I suggest that long term protected area management in DRC should consider how the value of resources for communities and protected areas have been changing throughout the history of conservation, and how to best share power and responsibilities with local resource users and stakeholders. This is only possible if conservation practices and approaches, governance process and institutions are transformed at multiple levels.
- Full Text:
- Date Issued: 2020
Consumer behaviour regarding stock market participation in South Africa
- Authors: Mbewe, Wise
- Date: 2020
- Subjects: Financial Literacy -- South Africa , Stock ownership -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50328 , vital:42107
- Description: South Africa (SA) has a highly sophisticated financial services sector that contributes significantly to the economy. A stock market forms a significant component of the financial sector of any economy. While the Johannesburg Stock Exchange (JSE) has managed to arouse interest of many South Africans, there appears to be apathy and inertia when it comes to actual participation in the stock market by South African consumers. Stock market non-participation is considered a “puzzle” in microeconomics and finance literature because it is not easy to explain the reason why many consumers, in spite of high stock returns, do not own listed shares. Thus, the primary objective of this study was to investigate consumer behaviour regarding stock market participation in SA by considering the antecedents and outcomes of stock market participation in SA.The study presented a theoretical literature review on the factors influencing stock market participation in SA. From the literature review, three sets of variables classified as independent variables, an intervening variable and dependent variables were identified. The independent variables (Demographic characteristics; Financial literacy; Investment risk tolerance; Communication; and Consumer trust) were identified as possibly influencing the intervening variable (Stock market participation) and ultimately the dependent variables (Client satisfaction and loyalty, Financial sustainability and Repurchase intentions). These variables were used to construct a hypothesised model and research hypotheses. The study further presented the research methodology (following a positivistic paradigm and quantitative research method), and the results of this study. In order to establish the influence of the independent variables on stock market participation, as well as ultimate influences on the dependent variables, an empirical investigation was conducted. Since it was not possible to reach all members of the target population, the population of this study was South African consumers located in four of the nine provinces, namely, Eastern Cape, Western Cape, Kwa-Zulu Natal and Gauteng. A sample of 510 respondents participated in the study.
- Full Text:
- Date Issued: 2020
- Authors: Mbewe, Wise
- Date: 2020
- Subjects: Financial Literacy -- South Africa , Stock ownership -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50328 , vital:42107
- Description: South Africa (SA) has a highly sophisticated financial services sector that contributes significantly to the economy. A stock market forms a significant component of the financial sector of any economy. While the Johannesburg Stock Exchange (JSE) has managed to arouse interest of many South Africans, there appears to be apathy and inertia when it comes to actual participation in the stock market by South African consumers. Stock market non-participation is considered a “puzzle” in microeconomics and finance literature because it is not easy to explain the reason why many consumers, in spite of high stock returns, do not own listed shares. Thus, the primary objective of this study was to investigate consumer behaviour regarding stock market participation in SA by considering the antecedents and outcomes of stock market participation in SA.The study presented a theoretical literature review on the factors influencing stock market participation in SA. From the literature review, three sets of variables classified as independent variables, an intervening variable and dependent variables were identified. The independent variables (Demographic characteristics; Financial literacy; Investment risk tolerance; Communication; and Consumer trust) were identified as possibly influencing the intervening variable (Stock market participation) and ultimately the dependent variables (Client satisfaction and loyalty, Financial sustainability and Repurchase intentions). These variables were used to construct a hypothesised model and research hypotheses. The study further presented the research methodology (following a positivistic paradigm and quantitative research method), and the results of this study. In order to establish the influence of the independent variables on stock market participation, as well as ultimate influences on the dependent variables, an empirical investigation was conducted. Since it was not possible to reach all members of the target population, the population of this study was South African consumers located in four of the nine provinces, namely, Eastern Cape, Western Cape, Kwa-Zulu Natal and Gauteng. A sample of 510 respondents participated in the study.
- Full Text:
- Date Issued: 2020
Contesting boundaries: a case of municipal demarcation disputes in Vuwani Vhembe District
- Authors: Khowa, Thandeka Promise
- Date: 2020
- Subjects: Geographical boundaries
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50767 , vital:42670
- Description: The research study in Vuwani Vhembe district sought to investigate demarcation disputes, the relationship between service delivery and demarcation disputes. The study further investigates the role of municipal demarcation board and local government adherence to sound governance principles and the causes of the demarcation dispute in Vuwani. The study additionally examines the conceptions and misconceptions, their impact on the current demarcation disputes in Vuwani. It further intended to establish the role and involvement of Vuwani stakeholders such as traditional structures/ leaders, civil unions, community members etc. in the processes of demarcating Vuwani. “What is the cause of Vuwani community member’s rejection of the re-demarcation, which is said to correct the past spatial injustices and promote municipal sizing, thus enabling better performance in service provision by municipalities?” The study employed a mixed-method involving the use of both quantitative (mini-survey) and qualitative (use of in-depth, semi structures interviews and focus group discussions). Research findings suggest that re-demarcation is a sensitive aspect/process in South Africa, mainly due to the past Apartheid era. There was forceful removal of people from their land supported by Apartheid legislation such as the Native Land Act 1913, Group Act 1950, Native Resettlement Act 1954 etc. Thus, fears of the past Apartheid system cloud any attempt to correct spatial injustices of the country. The new democratic South African government, therefore, needs to be cautious in its acts to correct the spatial injustices, thus adhering to sound governance principles. Findings reveal that several misconceptions and lack of adherence of good governance principles by the Municipal Demarcation Board and Local government have, to some extent, fueled the demarcation disputes in Vuwani. Municipal performance in the rendering of service delivery has a major impact and contributes to the community’s acceptance or rejection of demarcation/ amalgamations. The study further reveals that in Vuwani municipal performance with the establishment of the new Collins Chabane municipality has been clouded by fear of the unknown as this form of “demarcation of establishing a new municipality” altogether is relatively new. Rural land authority, the role of traditional leaders, ethnicity ties have all been found to have contributed to the disputes in Vuwani. Limpopo Province is home to three ethnic groups, namely, vaVhenda, baPedi and xiTsonga. The study findings have presented traits of tribalism as contributing to on-going demarcation disputes in Vuwani.
- Full Text:
- Date Issued: 2020
- Authors: Khowa, Thandeka Promise
- Date: 2020
- Subjects: Geographical boundaries
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50767 , vital:42670
- Description: The research study in Vuwani Vhembe district sought to investigate demarcation disputes, the relationship between service delivery and demarcation disputes. The study further investigates the role of municipal demarcation board and local government adherence to sound governance principles and the causes of the demarcation dispute in Vuwani. The study additionally examines the conceptions and misconceptions, their impact on the current demarcation disputes in Vuwani. It further intended to establish the role and involvement of Vuwani stakeholders such as traditional structures/ leaders, civil unions, community members etc. in the processes of demarcating Vuwani. “What is the cause of Vuwani community member’s rejection of the re-demarcation, which is said to correct the past spatial injustices and promote municipal sizing, thus enabling better performance in service provision by municipalities?” The study employed a mixed-method involving the use of both quantitative (mini-survey) and qualitative (use of in-depth, semi structures interviews and focus group discussions). Research findings suggest that re-demarcation is a sensitive aspect/process in South Africa, mainly due to the past Apartheid era. There was forceful removal of people from their land supported by Apartheid legislation such as the Native Land Act 1913, Group Act 1950, Native Resettlement Act 1954 etc. Thus, fears of the past Apartheid system cloud any attempt to correct spatial injustices of the country. The new democratic South African government, therefore, needs to be cautious in its acts to correct the spatial injustices, thus adhering to sound governance principles. Findings reveal that several misconceptions and lack of adherence of good governance principles by the Municipal Demarcation Board and Local government have, to some extent, fueled the demarcation disputes in Vuwani. Municipal performance in the rendering of service delivery has a major impact and contributes to the community’s acceptance or rejection of demarcation/ amalgamations. The study further reveals that in Vuwani municipal performance with the establishment of the new Collins Chabane municipality has been clouded by fear of the unknown as this form of “demarcation of establishing a new municipality” altogether is relatively new. Rural land authority, the role of traditional leaders, ethnicity ties have all been found to have contributed to the disputes in Vuwani. Limpopo Province is home to three ethnic groups, namely, vaVhenda, baPedi and xiTsonga. The study findings have presented traits of tribalism as contributing to on-going demarcation disputes in Vuwani.
- Full Text:
- Date Issued: 2020
Creating Citizen-Science for Groundwater Monitoring prior to potential Shale Gas Development in Cradock (South-Eastern Karoo, South Africa)
- Authors: Dhliwayo, Nyaradzo
- Date: 2020
- Subjects: Natural gas -- Prospecting -- Environmental aspects -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/48224 , vital:40526
- Description: Citizen Science is an integral tool for community engagement in scientific project design, implementation, data interpretation and reporting, in the quest to promote local capacity development as well as scientific knowledge. Based on the relevance of public engagement in aspects of the natural environment and associated scientific issues associated with the risks and opportunities of potential Shale Gas Development (SGD), a Citizen-Science (CS) study was designed in the Eastern Karoo region of South Africa linked to a Shale Gas Baseline Study initiated by the Africa Earth Observatory Network (AEON). As the pilot area of the baseline study, the town of Cradock was chosen to be the study area for this research; and CS was used to facilitate the identification of the Cradock community’s abilities to monitor the effects of potential SGD in this region. The development of new knowledge, skills and support, as well as a deeper understanding of the community’s role in Citizen Science studies, was also facilitated by this process. This study demonstrates the feasibility of integrating Citizen Science into existing community structures in Africa, thereby encouraging community engagement in the developmental programmes through participatory methods. Using a collaborative Action-Research Approach, consistent community roundtable meetings and key informant interviews served as invaluable platforms for the establishment of a 7-member community working group, that played the liaison role between the researcher and the Cradock community in the CS implementation process. Coupled with this was the recruitment and the training of eight young citizens in conducting a hydro-census and groundwater sampling for six boreholes within the identified Cradock commonage farms, as well as two boreholes on the farm of an identified emergent farmer. The engagements between the researcher, AEON scientists, the community working group and the community at large, enabled the successful implementation of CS training in two groundwater monitoring aspects and the testing of eleven water quality parameters. The training process was combined with the design and the development of a customised ‘Xoras’ Online Application, which was used to capture and share the hydro-census data recorded. Experiential learning in hydro-census and groundwater sampling resulted subsequently in an increased understanding and awareness of these aspects (Figure A). Even if SGD does not materialise in the South-Eastern Karoo, CS training will enable communities in the Shale-Gas Development precincts to participate in local decision-making forums on ground water, health, or on any related regional development projects. It is anticipated that the adoption of CS will ix promote future community engagements, especially about water across this water-scarce region, allowing for greater community-voice representation in resource-policy decisions related to potential Shale-Gas and related natural resource industries in the Karoo.
- Full Text:
- Date Issued: 2020
- Authors: Dhliwayo, Nyaradzo
- Date: 2020
- Subjects: Natural gas -- Prospecting -- Environmental aspects -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/48224 , vital:40526
- Description: Citizen Science is an integral tool for community engagement in scientific project design, implementation, data interpretation and reporting, in the quest to promote local capacity development as well as scientific knowledge. Based on the relevance of public engagement in aspects of the natural environment and associated scientific issues associated with the risks and opportunities of potential Shale Gas Development (SGD), a Citizen-Science (CS) study was designed in the Eastern Karoo region of South Africa linked to a Shale Gas Baseline Study initiated by the Africa Earth Observatory Network (AEON). As the pilot area of the baseline study, the town of Cradock was chosen to be the study area for this research; and CS was used to facilitate the identification of the Cradock community’s abilities to monitor the effects of potential SGD in this region. The development of new knowledge, skills and support, as well as a deeper understanding of the community’s role in Citizen Science studies, was also facilitated by this process. This study demonstrates the feasibility of integrating Citizen Science into existing community structures in Africa, thereby encouraging community engagement in the developmental programmes through participatory methods. Using a collaborative Action-Research Approach, consistent community roundtable meetings and key informant interviews served as invaluable platforms for the establishment of a 7-member community working group, that played the liaison role between the researcher and the Cradock community in the CS implementation process. Coupled with this was the recruitment and the training of eight young citizens in conducting a hydro-census and groundwater sampling for six boreholes within the identified Cradock commonage farms, as well as two boreholes on the farm of an identified emergent farmer. The engagements between the researcher, AEON scientists, the community working group and the community at large, enabled the successful implementation of CS training in two groundwater monitoring aspects and the testing of eleven water quality parameters. The training process was combined with the design and the development of a customised ‘Xoras’ Online Application, which was used to capture and share the hydro-census data recorded. Experiential learning in hydro-census and groundwater sampling resulted subsequently in an increased understanding and awareness of these aspects (Figure A). Even if SGD does not materialise in the South-Eastern Karoo, CS training will enable communities in the Shale-Gas Development precincts to participate in local decision-making forums on ground water, health, or on any related regional development projects. It is anticipated that the adoption of CS will ix promote future community engagements, especially about water across this water-scarce region, allowing for greater community-voice representation in resource-policy decisions related to potential Shale-Gas and related natural resource industries in the Karoo.
- Full Text:
- Date Issued: 2020
Data transport over optical fibre for ska using advanced modulation flexible spectrum technology
- Authors: Dlamini, Phumla Patience
- Date: 2020
- Subjects: Fiber optics
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/50666 , vital:42329
- Description: Flexible Spectrum Dense Wavelength Division Multiplexed (DWDM) optical fibre networks are next-generation technology for handling extremely high data rates of the kind produced by MeerKAT and SKA.We optimise the flexible spectrum for real-time dynamic channel wavelength assignment, to ensure optimum network performance. We needed to identify and develop novel hardware and dynamic algorithms for these networks to function optimally to perform critical tasks. Such tasks include wavelength assignment, signal routing, network restoration and network protection. The antennas of the Square Kilometre Array (SKA) network connect to the correlator and data processor in a simple point-to-point fixed configuration. The connection of the astronomer users to the data processor, however, requires a more complex network architecture. This is because the network has users scattered around South Africa, Africa and the whole world. This calls for upgrade of the classical fixed wavelength spectrum grids, to flexible spectrum grid that has improved capacity, reliable, simple and cost-effectiveness through sharing of network infrastructure. The exponential growth of data traffic in current optical communication networks requires higher capacity for the bandwidth demands at a reduced cost per bit. All-optical signal processing is a promising technique to improve network resource utilisation and resolve wavelength contention associated with the flexible spectrum. Flexible Spectrum Dense Wavelength Division Multiplexed (DWDM) optical fibre networks are next-generation technology for handling extremely high data rates of the kind produced by MeerKAT and SKA. Each DWDM channel is capable of 10 Gbps transmission rate, which is sliceable into finer flexible grid 12.5 GHz granularity to offer the network elastic spectrum and channel spacing capable of signal routing and wavelength switching for the scalability of aggregate bandwidth. The variable-sized portions of the flexible spectrum assignment to end users at different speeds depend on bandwidth demand, allowing efficient utilisation of the spectrum resources. The entire bandwidth of dynamic optical connections must be contiguously allocated. However, there is an introduction of spectrum fragmentation due to spectrum contiguity related to the optical channels having different width. Thus large traffic demands are likely to experience blocking regardless of available bandwidth. To minimise the congestion and cost-effectively obtain high performance, the optical network must be reconfigurable, achievable by adding wavelength as an extra degree of freedom for effectiveness. This can introduce colourless, directionless and contentionless reconfigurability to route individual wavelengths from fibre to fibre across multiple nodes to avoid wavelength blocking/collisions, increasing the flexibility and capacity of a network. For these networks to function optimally, novel hardware and dynamic algorithms identification and development is a critical task. Such tasks include wavelength assignment, signal routing, network restoration and network protection. In this work, we for the first time to our knowledge proposed a spectrum defragmentation technique through reallocation of the central frequency of the optical transmitter, to increase the probability of finding a sufficient continuous spectrum. This is to improve network resource utilisation, capacity and resolve wavelength contention associated with a flexible spectrum in optical communication networks. The following chapter provides details on a flexible spectrum in optical fibre networks utilising DWDM, optimising transmitter-receivers, advanced modulation formats, coherent detection, reconfigurable optical add and drop multiplexer (ROADM) technology to implement hardware and middleware platforms which address growing bandwidth demands for scalability, flexibility and cost-efficiency. A major attribute is tunable lasers, an essential component for future flexible spectrum with application to wavelength switching, routing, wavelength conversion and ROADM for the multi-node optical network through spectrum flexibility and cost-effective sharing of fibre links, transmitters and receivers. Spectrum slicing into fine granular sub-carriers and assigning several frequency slots to accommodate diverse traffic demands is a viable approach. This work experimentally presents a spectral efficient technique for bandwidth variability, wavelength allocation, routing, defragmentation and wavelength selective switches in the nodes of a network, capable of removing the fixed grid spacing using low cost, high bandwidth, power-efficient and wavelength-tunable vertical-cavity surface-emitting laser (VCSEL) transmitter directly modulated with 10 Gbps data. This to ensure that majority of the spectrum utilisation at finer channel spacing, wastage of the spectrum resource as caused by the wavelength continuity constraint reduction and it improves bandwidth utilisation. The technique is flexible in terms of modulation formats and accommodates various formats with spectrally continuous channels, fulfilling the future bandwidth demands with transmissions beyond 100 Gbps per channel while maintaining spectral efficiency.
- Full Text:
- Date Issued: 2020
- Authors: Dlamini, Phumla Patience
- Date: 2020
- Subjects: Fiber optics
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/50666 , vital:42329
- Description: Flexible Spectrum Dense Wavelength Division Multiplexed (DWDM) optical fibre networks are next-generation technology for handling extremely high data rates of the kind produced by MeerKAT and SKA.We optimise the flexible spectrum for real-time dynamic channel wavelength assignment, to ensure optimum network performance. We needed to identify and develop novel hardware and dynamic algorithms for these networks to function optimally to perform critical tasks. Such tasks include wavelength assignment, signal routing, network restoration and network protection. The antennas of the Square Kilometre Array (SKA) network connect to the correlator and data processor in a simple point-to-point fixed configuration. The connection of the astronomer users to the data processor, however, requires a more complex network architecture. This is because the network has users scattered around South Africa, Africa and the whole world. This calls for upgrade of the classical fixed wavelength spectrum grids, to flexible spectrum grid that has improved capacity, reliable, simple and cost-effectiveness through sharing of network infrastructure. The exponential growth of data traffic in current optical communication networks requires higher capacity for the bandwidth demands at a reduced cost per bit. All-optical signal processing is a promising technique to improve network resource utilisation and resolve wavelength contention associated with the flexible spectrum. Flexible Spectrum Dense Wavelength Division Multiplexed (DWDM) optical fibre networks are next-generation technology for handling extremely high data rates of the kind produced by MeerKAT and SKA. Each DWDM channel is capable of 10 Gbps transmission rate, which is sliceable into finer flexible grid 12.5 GHz granularity to offer the network elastic spectrum and channel spacing capable of signal routing and wavelength switching for the scalability of aggregate bandwidth. The variable-sized portions of the flexible spectrum assignment to end users at different speeds depend on bandwidth demand, allowing efficient utilisation of the spectrum resources. The entire bandwidth of dynamic optical connections must be contiguously allocated. However, there is an introduction of spectrum fragmentation due to spectrum contiguity related to the optical channels having different width. Thus large traffic demands are likely to experience blocking regardless of available bandwidth. To minimise the congestion and cost-effectively obtain high performance, the optical network must be reconfigurable, achievable by adding wavelength as an extra degree of freedom for effectiveness. This can introduce colourless, directionless and contentionless reconfigurability to route individual wavelengths from fibre to fibre across multiple nodes to avoid wavelength blocking/collisions, increasing the flexibility and capacity of a network. For these networks to function optimally, novel hardware and dynamic algorithms identification and development is a critical task. Such tasks include wavelength assignment, signal routing, network restoration and network protection. In this work, we for the first time to our knowledge proposed a spectrum defragmentation technique through reallocation of the central frequency of the optical transmitter, to increase the probability of finding a sufficient continuous spectrum. This is to improve network resource utilisation, capacity and resolve wavelength contention associated with a flexible spectrum in optical communication networks. The following chapter provides details on a flexible spectrum in optical fibre networks utilising DWDM, optimising transmitter-receivers, advanced modulation formats, coherent detection, reconfigurable optical add and drop multiplexer (ROADM) technology to implement hardware and middleware platforms which address growing bandwidth demands for scalability, flexibility and cost-efficiency. A major attribute is tunable lasers, an essential component for future flexible spectrum with application to wavelength switching, routing, wavelength conversion and ROADM for the multi-node optical network through spectrum flexibility and cost-effective sharing of fibre links, transmitters and receivers. Spectrum slicing into fine granular sub-carriers and assigning several frequency slots to accommodate diverse traffic demands is a viable approach. This work experimentally presents a spectral efficient technique for bandwidth variability, wavelength allocation, routing, defragmentation and wavelength selective switches in the nodes of a network, capable of removing the fixed grid spacing using low cost, high bandwidth, power-efficient and wavelength-tunable vertical-cavity surface-emitting laser (VCSEL) transmitter directly modulated with 10 Gbps data. This to ensure that majority of the spectrum utilisation at finer channel spacing, wastage of the spectrum resource as caused by the wavelength continuity constraint reduction and it improves bandwidth utilisation. The technique is flexible in terms of modulation formats and accommodates various formats with spectrally continuous channels, fulfilling the future bandwidth demands with transmissions beyond 100 Gbps per channel while maintaining spectral efficiency.
- Full Text:
- Date Issued: 2020
Database and guide for Lesotho wool and mohair production and quality
- Authors: Maqalika, Papali Elizabeth
- Date: 2020
- Subjects: Mohair -- Dissertations -- Lesotho , Wool -- Dissertations -- Lesotho Textile fabrics -- Lesotho Textile industry -- Lesotho
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/49148 , vital:41605
- Description: Lesotho produces significant quantities of Merino apparel wool and mohair, both of a quality that allows them to compete on the global market and to make a significant contribution to the economy of the country. Nevertheless, very little production and quality data and trends of these fibres have been documented. This is a serious disadvantage in terms of international trading and benchmarking as well as attempts to improve the production and quality of Lesotho wool and mohair. In the light of the aforementioned, the available production and quality data of the past 10 years have been captured and analysed for trends and also benchmarking, where considered applicable. The main focus is on fibre diameter (fineness), staple length, and yield since they largely determine fibre quality, application and price. Some quality related tests were undertaken to fill certain important gaps in the available data. In addition, prickle and medullation were evaluated on representative wool and mohair samples, respectively, because they represent important quality measures for apparel wool and mohair, respectively. It was found that Lesotho wool and mohair are of a fairly good and internationally competitive quality, with the wool having an average fibre diameter (MFD) of ≈20μm, an average staple length of about 64mm, an average VM level of about 4%, an average yield of about 57%, and the annual production being about 4 million kilograms greasy. The average staple length of the mohair was about 140mm, average MFD about 29μm and the average medullation, which unless otherwise specified, refers to the objectionable medullated fibres (kemp type) including the flat medullated fibre, relatively high at about 5.7%. The latter is certainly an area of concern which needs attention and improvement. It was found that the prickle level (Comfort Factor), of some of the wools tested was of such a level as to make the wool suitable for wearing against the skin. With respect to mohair, there is considerable scope to substantially reduce the level of objectionable medullated (kemp style) fibre level through the appropriate breeding interventions. Production of both wool and mohair has increased slightly over the ten years covered by this study. It also became apparent that Lesotho wool and mohair quality and production are greatly influenced by the farming practices and climatic conditions. Greater adoption of the merino sheep breed, sheds/barns and sheep coats are suggested as ways to reduce mortality rate (due to extremely cold temperatures), improve quality and increase yield and production. Some farming practices such as the lack of barns, supplementary feeding and veterinary care present constraints in terms of production of both wool and mohair. The districts in the Highlands region had the highest production of mostly wool, this being ascribed to better pastures, climatic and other conditions conducive to wool and mohair production. Both wool and mohair are considered to have potential for improved quality and production, which could be affected by appropriate interventions by the Small Agricultural and Development Project (SADP) and others through National Wool and Mohair Growers Association (NWMGA). Nevertheless, since the wool and mohair growers (farmers) do not form part of these and other interventions, they do not readily adopt the various strategies and decisions and do not receive the associated benefits immediately. It is therefore advised that local farmers, relevant educators and researchers be represented in policy and other decision making forums. In this way, educational campaigns will be demand driven with greater chance of adoption and success.
- Full Text:
- Date Issued: 2020
- Authors: Maqalika, Papali Elizabeth
- Date: 2020
- Subjects: Mohair -- Dissertations -- Lesotho , Wool -- Dissertations -- Lesotho Textile fabrics -- Lesotho Textile industry -- Lesotho
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/49148 , vital:41605
- Description: Lesotho produces significant quantities of Merino apparel wool and mohair, both of a quality that allows them to compete on the global market and to make a significant contribution to the economy of the country. Nevertheless, very little production and quality data and trends of these fibres have been documented. This is a serious disadvantage in terms of international trading and benchmarking as well as attempts to improve the production and quality of Lesotho wool and mohair. In the light of the aforementioned, the available production and quality data of the past 10 years have been captured and analysed for trends and also benchmarking, where considered applicable. The main focus is on fibre diameter (fineness), staple length, and yield since they largely determine fibre quality, application and price. Some quality related tests were undertaken to fill certain important gaps in the available data. In addition, prickle and medullation were evaluated on representative wool and mohair samples, respectively, because they represent important quality measures for apparel wool and mohair, respectively. It was found that Lesotho wool and mohair are of a fairly good and internationally competitive quality, with the wool having an average fibre diameter (MFD) of ≈20μm, an average staple length of about 64mm, an average VM level of about 4%, an average yield of about 57%, and the annual production being about 4 million kilograms greasy. The average staple length of the mohair was about 140mm, average MFD about 29μm and the average medullation, which unless otherwise specified, refers to the objectionable medullated fibres (kemp type) including the flat medullated fibre, relatively high at about 5.7%. The latter is certainly an area of concern which needs attention and improvement. It was found that the prickle level (Comfort Factor), of some of the wools tested was of such a level as to make the wool suitable for wearing against the skin. With respect to mohair, there is considerable scope to substantially reduce the level of objectionable medullated (kemp style) fibre level through the appropriate breeding interventions. Production of both wool and mohair has increased slightly over the ten years covered by this study. It also became apparent that Lesotho wool and mohair quality and production are greatly influenced by the farming practices and climatic conditions. Greater adoption of the merino sheep breed, sheds/barns and sheep coats are suggested as ways to reduce mortality rate (due to extremely cold temperatures), improve quality and increase yield and production. Some farming practices such as the lack of barns, supplementary feeding and veterinary care present constraints in terms of production of both wool and mohair. The districts in the Highlands region had the highest production of mostly wool, this being ascribed to better pastures, climatic and other conditions conducive to wool and mohair production. Both wool and mohair are considered to have potential for improved quality and production, which could be affected by appropriate interventions by the Small Agricultural and Development Project (SADP) and others through National Wool and Mohair Growers Association (NWMGA). Nevertheless, since the wool and mohair growers (farmers) do not form part of these and other interventions, they do not readily adopt the various strategies and decisions and do not receive the associated benefits immediately. It is therefore advised that local farmers, relevant educators and researchers be represented in policy and other decision making forums. In this way, educational campaigns will be demand driven with greater chance of adoption and success.
- Full Text:
- Date Issued: 2020