Freshwater invasive alien crayfish species in South Africa: testing eDNA assessment and DNA barcoding
- Mdidimba, Nonkazimulo Dorothea
- Authors: Mdidimba, Nonkazimulo Dorothea
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424413 , vital:72151
- Description: The expansion of the wild populations of the two invasive alien crayfish species, i.e., Cherax quadricarinatus and Procambarus clarkii in South Africa is of high concern. Given this, innovative and improved monitoring methods are required to be explored in order to effectively detect and manage their spread. Environmental DNA (eDNA) has shown promising and reliable results to detect and monitor alien crayfish in freshwater systems even at low densities. This research study aimed to field-test the application of eDNA for detecting and monitoring invasive alien freshwater crayfish species (IAFCs) in South African freshwater systems (Chapter 2). Further, this study also aimed to confirm the true taxonomic identity of the IAFCs in South African freshwater systems by using DNA barcoding to avoid potential misidentifications with morphological identification alone (Chapter 3). Also, ectocommensal temnocephalans and leeches attached to the crayfishes were also identified with DNA barcoding. The mitochondrial COI gene fragment of the crayfishes and the ectocommensal temnocephalans and leeches was amplified, sequenced, and used for species identification. For eDNA monitoring of C. cainii, C. quadricarinatus and P. clarkii, water samples were collected from Eastern Cape, Free State and KwaZulu Natal sites that are known to house these species. The current study did not detect the eDNA of the wild populations of both C. quadricarinatus and P. clarkii. This failure was encountered despite employing several methods, such as, end-point polymerase chain reaction (PCR), quantitative PCR (qPCR) and next-generation sequencing (NGS). The eDNA assessment to detect IAFCs in the wild populations is discussed in detail, and corrective measures suggested (Chapter 2). However, only C. cainii was able to be detected by eDNA. Cherax cainii is housed/farmed in an aquaculture facility (Vaughn Bursey’s Stock Farm in Eastern Cape) with large number of individuals per pond. For this, NGS was able to detect C. cainii but the other two methods, end-point PCR and qPCR were not able to detect the species. Based on the results, refinement of eDNA monitoring methods for the South African freshwater systems is recommended. Evaluation of different DNA collection methods, preservation, DNA extraction kits and primer design to obtain effective eDNA detection is discussed as possible sources of error. Interestingly, the newly established population of P. clarkii in Mimosa Dam in Free State was infested with alien leeches, that were confirmed by DNA barcoding to be Helobdella europaea and Helobdella octatestica. Consequently, this study reports for the first time in South Africa the presence of this alien freshwater leeches. The presence of alien leeches and P. clarkii suggests a double invasion in Mimosa Dam, P. clarkii seems to continue expanding its range in the country. However, the long-established population of P. clarkii in Driehoek Farm in Mpumalanga, which has been in the country for over 30 years did not have any leech or temnocephalan infestation. This could suggest several interesting ecological phenomena, including environmental filtering over time of the co-invaders, differential source populations, and post-introduction adaptation. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mdidimba, Nonkazimulo Dorothea
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424413 , vital:72151
- Description: The expansion of the wild populations of the two invasive alien crayfish species, i.e., Cherax quadricarinatus and Procambarus clarkii in South Africa is of high concern. Given this, innovative and improved monitoring methods are required to be explored in order to effectively detect and manage their spread. Environmental DNA (eDNA) has shown promising and reliable results to detect and monitor alien crayfish in freshwater systems even at low densities. This research study aimed to field-test the application of eDNA for detecting and monitoring invasive alien freshwater crayfish species (IAFCs) in South African freshwater systems (Chapter 2). Further, this study also aimed to confirm the true taxonomic identity of the IAFCs in South African freshwater systems by using DNA barcoding to avoid potential misidentifications with morphological identification alone (Chapter 3). Also, ectocommensal temnocephalans and leeches attached to the crayfishes were also identified with DNA barcoding. The mitochondrial COI gene fragment of the crayfishes and the ectocommensal temnocephalans and leeches was amplified, sequenced, and used for species identification. For eDNA monitoring of C. cainii, C. quadricarinatus and P. clarkii, water samples were collected from Eastern Cape, Free State and KwaZulu Natal sites that are known to house these species. The current study did not detect the eDNA of the wild populations of both C. quadricarinatus and P. clarkii. This failure was encountered despite employing several methods, such as, end-point polymerase chain reaction (PCR), quantitative PCR (qPCR) and next-generation sequencing (NGS). The eDNA assessment to detect IAFCs in the wild populations is discussed in detail, and corrective measures suggested (Chapter 2). However, only C. cainii was able to be detected by eDNA. Cherax cainii is housed/farmed in an aquaculture facility (Vaughn Bursey’s Stock Farm in Eastern Cape) with large number of individuals per pond. For this, NGS was able to detect C. cainii but the other two methods, end-point PCR and qPCR were not able to detect the species. Based on the results, refinement of eDNA monitoring methods for the South African freshwater systems is recommended. Evaluation of different DNA collection methods, preservation, DNA extraction kits and primer design to obtain effective eDNA detection is discussed as possible sources of error. Interestingly, the newly established population of P. clarkii in Mimosa Dam in Free State was infested with alien leeches, that were confirmed by DNA barcoding to be Helobdella europaea and Helobdella octatestica. Consequently, this study reports for the first time in South Africa the presence of this alien freshwater leeches. The presence of alien leeches and P. clarkii suggests a double invasion in Mimosa Dam, P. clarkii seems to continue expanding its range in the country. However, the long-established population of P. clarkii in Driehoek Farm in Mpumalanga, which has been in the country for over 30 years did not have any leech or temnocephalan infestation. This could suggest several interesting ecological phenomena, including environmental filtering over time of the co-invaders, differential source populations, and post-introduction adaptation. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
From euphoria to disenchantment: the intangible in Black post-apartheid South African fiction
- Authors: Kenqu, Amanda Yoliswa
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432466 , vital:72873
- Description: Access restricted. Exptected release date 2025. , Thesis (PhD) -- Faculty of Humanities, Literary Studies in English, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Kenqu, Amanda Yoliswa
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432466 , vital:72873
- Description: Access restricted. Exptected release date 2025. , Thesis (PhD) -- Faculty of Humanities, Literary Studies in English, 2023
- Full Text:
- Date Issued: 2023-10-13
From more sustainable isocyanide-based multicomponent reactions to spiro-heterocyclic compound syntheses
- Authors: Salami, Sodeeq Aderotimi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432229 , vital:72853 , DOI 10.21504/10962/432229
- Description: The global pharmaceutical industry has undergone profound transformations in the past two decades in the search for new drugs. For this reason, most pharmaceutical companies made significant investments not only in the development of new drugs but new methodologies. Modern drug development is confronted with the challenge of developing chemical reactions that are highly capable of providing most of the elements of structural complexity and diversity with the fewest possible synthetic steps for the specific target with the most intriguing properties. The discovery of more sustainable, environmentally friendly reactions capable of forming multiple bonds in a single step has been a challenge in organic synthesis over the years. Many organic chemists have recently started focusing on creative ways of reducing environmental pollution. The use of hazardous solvents has been reduced or eliminated in research to limit harm to both people and the environment. The pursuit of this goal has drawn many organic chemists to the study of various sustainable synthetic techniques including catalysis, aqueous organic reactions and mechanochemistry. The scope of this thesis was to apply sustainable techniques to design multicomponent synthetic protocols for the Passerini reaction and further apply these new protocols to construct spiro-heterocyclic compounds, all based on green chemistry principles. There is a need to develop rapid, efficient, and versatile strategies for the synthesis of bioactive molecules via multicomponent reactions. This project tried to avoid some of the pitfalls of traditional approaches, such as toxicity, low yield, long reaction times, harsh conditions, experimental complexity, and limited functionalization scope. This was achieved by focussing on the use of isonitriles and isothiocyanates as key reactive intermediates, and making extensive use of aqueous reaction conditions, mechanochemistry and microwave activation. , Thesis (PhD) -- Faculty of Science, Chemistry, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Salami, Sodeeq Aderotimi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432229 , vital:72853 , DOI 10.21504/10962/432229
- Description: The global pharmaceutical industry has undergone profound transformations in the past two decades in the search for new drugs. For this reason, most pharmaceutical companies made significant investments not only in the development of new drugs but new methodologies. Modern drug development is confronted with the challenge of developing chemical reactions that are highly capable of providing most of the elements of structural complexity and diversity with the fewest possible synthetic steps for the specific target with the most intriguing properties. The discovery of more sustainable, environmentally friendly reactions capable of forming multiple bonds in a single step has been a challenge in organic synthesis over the years. Many organic chemists have recently started focusing on creative ways of reducing environmental pollution. The use of hazardous solvents has been reduced or eliminated in research to limit harm to both people and the environment. The pursuit of this goal has drawn many organic chemists to the study of various sustainable synthetic techniques including catalysis, aqueous organic reactions and mechanochemistry. The scope of this thesis was to apply sustainable techniques to design multicomponent synthetic protocols for the Passerini reaction and further apply these new protocols to construct spiro-heterocyclic compounds, all based on green chemistry principles. There is a need to develop rapid, efficient, and versatile strategies for the synthesis of bioactive molecules via multicomponent reactions. This project tried to avoid some of the pitfalls of traditional approaches, such as toxicity, low yield, long reaction times, harsh conditions, experimental complexity, and limited functionalization scope. This was achieved by focussing on the use of isonitriles and isothiocyanates as key reactive intermediates, and making extensive use of aqueous reaction conditions, mechanochemistry and microwave activation. , Thesis (PhD) -- Faculty of Science, Chemistry, 2023
- Full Text:
- Date Issued: 2023-10-13
Gender, informality and urban livelihoods: eamining the livelihood strategies adopted by Black female street vendors in Makhanda, Eastern Cape
- Authors: Khoele, Lineo
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/431474 , vital:72775
- Description: This study sought to examine livelihood strategies adopted by black female street vendors in Makhanda, Eastern Cape. The street vending activities that were undertaken by the research participants included selling: cooked foods, fresh fruit and vegetables, eggs, and beauty products. This study used the Sustainable Livelihood Approach (SLA) to examine the livelihood strategies of black female street vendors in Makhanda. The SL approach was chosen as an ideal framework for a study of this nature as it holistically and traditionally focuses on vulnerable population groups around the world. More importantly, the SLA gives agency to these vulnerable groups, as it prioritizes their innovative techniques in mobilizing diverse assets at their disposal in order to survive. The study is, therefore, ideal as it also gives agency to selected black female street vendors by examining how they utilized diverse assets at their disposal to sustain their livelihoods. This study seeks to contribute to the ongoing debate on urban livelihoods and the informal economy in South Africa, focusing particularly on the different methods or strategies employed by black female street vendors to enhance the sustainability of street vending as a livelihood. Due to the nature of this study, which seeks to capture the lived experiences of the selected black female street vendors in Makhanda, qualitative research methodologies were used to collect and analyse data. This study proved street vending to be a survival strategy that is used by black unskilled women in pursuit of livelihoods. It argues that, faced with the socio-economic realities associated with high unemployment, street vending can be used by many to best support their households. When it comes to livelihood strategies, this study found that, livelihood diversification is the most common livelihood strategy adopted by street vendors in Makhanda, with the only difference being the type of diversification adopted. Two forms of livelihood diversification strategies were identified in this study, and these included: product diversification and income diversification. The conclusion drawn from the findings argues that the selected street vendors in Makhanda strategically used different assets accessible to them to enhance and sustain their livelihoods. The study found that despite the different structural challenges faced by street vendors in Makhanda, the selected black female street vendors are able to meet their livelihood outcomes and support their families through engaging in street vending. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Khoele, Lineo
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/431474 , vital:72775
- Description: This study sought to examine livelihood strategies adopted by black female street vendors in Makhanda, Eastern Cape. The street vending activities that were undertaken by the research participants included selling: cooked foods, fresh fruit and vegetables, eggs, and beauty products. This study used the Sustainable Livelihood Approach (SLA) to examine the livelihood strategies of black female street vendors in Makhanda. The SL approach was chosen as an ideal framework for a study of this nature as it holistically and traditionally focuses on vulnerable population groups around the world. More importantly, the SLA gives agency to these vulnerable groups, as it prioritizes their innovative techniques in mobilizing diverse assets at their disposal in order to survive. The study is, therefore, ideal as it also gives agency to selected black female street vendors by examining how they utilized diverse assets at their disposal to sustain their livelihoods. This study seeks to contribute to the ongoing debate on urban livelihoods and the informal economy in South Africa, focusing particularly on the different methods or strategies employed by black female street vendors to enhance the sustainability of street vending as a livelihood. Due to the nature of this study, which seeks to capture the lived experiences of the selected black female street vendors in Makhanda, qualitative research methodologies were used to collect and analyse data. This study proved street vending to be a survival strategy that is used by black unskilled women in pursuit of livelihoods. It argues that, faced with the socio-economic realities associated with high unemployment, street vending can be used by many to best support their households. When it comes to livelihood strategies, this study found that, livelihood diversification is the most common livelihood strategy adopted by street vendors in Makhanda, with the only difference being the type of diversification adopted. Two forms of livelihood diversification strategies were identified in this study, and these included: product diversification and income diversification. The conclusion drawn from the findings argues that the selected street vendors in Makhanda strategically used different assets accessible to them to enhance and sustain their livelihoods. The study found that despite the different structural challenges faced by street vendors in Makhanda, the selected black female street vendors are able to meet their livelihood outcomes and support their families through engaging in street vending. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2023
- Full Text:
- Date Issued: 2023-10-13
Halogenated Aza-BODIPY dyes for photodynamic anticancer and antimicrobial activity studies
- Magwaza, Temlandvo Matshidiso
- Authors: Magwaza, Temlandvo Matshidiso
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424514 , vital:72160
- Description: This thesis reports on the synthesis and characterisation of differently substituted aza-BODIPY dyes for use in photodynamic antimicrobial chemotherapy (PACT) and photodynamic therapy (PDT) activity studies. The aza-BODIPY dyes were synthesised by adding phenyl and naphthyl rings at the 3,5-positions of the aza-BODIPY core, with methylthiolphenyl (9a and 9b, respectively) or thien-2-yl rings (9c and 9d, respectively) at the 1,7-positions. 9a-c were iodinated at the 2-position to form 10a-c, respectively, while 9d was diiodinated at the 2,6-positions to form 10d. The methylthiolphenyl-substituted dyes (10a and 10b) were successfully conjugated to gold nanoparticles (AuNPs) to form nanoparticles conjugates (10a-AuNPs and 10b-AuNPs), while attempts to conjugate the thien-2-yl-substituted dyes were unsuccessful. The photophysicochemical properties of 9a-d, 10a-d and nanoconjugates 10a-AuNPs and 10b-AuNPs were investigated to determine their suitability for use in the applications. Adding heavy atoms such as iodine at the 2,6-positions of the aza-BODIPY led to enhanced singlet oxygen generation since these dyes displayed moderate to high singlet oxygen quantum yields. None of the dyes exhibited any fluorescence. The PACT activity studies for 9c-d, 10a-d, and the 10a-AuNPs and 10b-AuNPs were carried out against Staphylococcus aureus and Escherichia coli with a Thorlabs M660L3 light-emitting diode (LED) with an irradiance of 280 mW/cm2 for all dyes other than 10d. A Thorlabs M730L4 LED with an irradiance of 160 mW/cm2 was used for 10d. Time dependence studies were only carried out against Staphylococcus aureus, so very low log reductions were observed against Escherichia coli in initial concentration studies. The 10a-AuNP and 10b-AuNP nanoconjugates exhibited high antimicrobial activity with a log reduction of 9.41 and 0.00% viable colonies, while the iodinated aza-BODIPY had a log reduction of 8.94. The in vitro photodynamic therapy activities and dark cytotoxicity were investigated against human MCF-7 breast cancer cells for dyes 9c-d and 10c-d with a Thorlabs M660L3 LED (280 mW/cm2) for all dyes. The dark cytotoxicity was minimal in each case with IC50 > 50. Iodinated dyes 10c and 10d had IC50 values of 11.6 and 8.2 μM, respectively, and non-iodinated dyes 9c and 9d had IC50 values of 12.5 and 19.2 μM. The heavy atom effect associated with the iodine atoms increases the singlet oxygen quantum yield and enhances the suitability of the dyes for photodynamic therapy. , Thesis (MSc) -- Faculty of Science, Chemistry, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Magwaza, Temlandvo Matshidiso
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424514 , vital:72160
- Description: This thesis reports on the synthesis and characterisation of differently substituted aza-BODIPY dyes for use in photodynamic antimicrobial chemotherapy (PACT) and photodynamic therapy (PDT) activity studies. The aza-BODIPY dyes were synthesised by adding phenyl and naphthyl rings at the 3,5-positions of the aza-BODIPY core, with methylthiolphenyl (9a and 9b, respectively) or thien-2-yl rings (9c and 9d, respectively) at the 1,7-positions. 9a-c were iodinated at the 2-position to form 10a-c, respectively, while 9d was diiodinated at the 2,6-positions to form 10d. The methylthiolphenyl-substituted dyes (10a and 10b) were successfully conjugated to gold nanoparticles (AuNPs) to form nanoparticles conjugates (10a-AuNPs and 10b-AuNPs), while attempts to conjugate the thien-2-yl-substituted dyes were unsuccessful. The photophysicochemical properties of 9a-d, 10a-d and nanoconjugates 10a-AuNPs and 10b-AuNPs were investigated to determine their suitability for use in the applications. Adding heavy atoms such as iodine at the 2,6-positions of the aza-BODIPY led to enhanced singlet oxygen generation since these dyes displayed moderate to high singlet oxygen quantum yields. None of the dyes exhibited any fluorescence. The PACT activity studies for 9c-d, 10a-d, and the 10a-AuNPs and 10b-AuNPs were carried out against Staphylococcus aureus and Escherichia coli with a Thorlabs M660L3 light-emitting diode (LED) with an irradiance of 280 mW/cm2 for all dyes other than 10d. A Thorlabs M730L4 LED with an irradiance of 160 mW/cm2 was used for 10d. Time dependence studies were only carried out against Staphylococcus aureus, so very low log reductions were observed against Escherichia coli in initial concentration studies. The 10a-AuNP and 10b-AuNP nanoconjugates exhibited high antimicrobial activity with a log reduction of 9.41 and 0.00% viable colonies, while the iodinated aza-BODIPY had a log reduction of 8.94. The in vitro photodynamic therapy activities and dark cytotoxicity were investigated against human MCF-7 breast cancer cells for dyes 9c-d and 10c-d with a Thorlabs M660L3 LED (280 mW/cm2) for all dyes. The dark cytotoxicity was minimal in each case with IC50 > 50. Iodinated dyes 10c and 10d had IC50 values of 11.6 and 8.2 μM, respectively, and non-iodinated dyes 9c and 9d had IC50 values of 12.5 and 19.2 μM. The heavy atom effect associated with the iodine atoms increases the singlet oxygen quantum yield and enhances the suitability of the dyes for photodynamic therapy. , Thesis (MSc) -- Faculty of Science, Chemistry, 2023
- Full Text:
- Date Issued: 2023-10-13
Health communication for antimicrobial resistance and stewardship in the Makana Local Municipality, South Africa
- Authors: Sharma, Samridhi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/431531 , vital:72783
- Description: Access restricted. Expected release date 2025. , Thesis (PhD) -- Faculty of Pharmacy, Pharmacy, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Sharma, Samridhi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/431531 , vital:72783
- Description: Access restricted. Expected release date 2025. , Thesis (PhD) -- Faculty of Pharmacy, Pharmacy, 2023
- Full Text:
- Date Issued: 2023-10-13
HI View of the Norma Galaxy Cluster with MeerKAT
- Authors: Mophahlane, Koketso Vincent
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/432530 , vital:72878
- Description: Studies reveal that galaxies assemble into clusters as gas-rich, active star-forming disks and eventually settle in the virialized core as quenched early-type galaxies with depleted gas. To examine environmental effects responsible for the quenched population in the cluster core, we exploit the higher sensitivity of the MeerKAT telescope to probe Hi properties of galaxies in the Norma cluster. The Norma cluster is an ideal laboratory for this study since it is a rich and massive cluster of nearby galaxies. The Hi data cube used covers a velocity range of 483 − 11, 113 km/s, with a noise rms sensitivity of 0.09 mJy/beam and an angular resolution of ∼ 14.65′′ × 9.28′′. A total of 25 reliable Hi sources were detected over the entire velocity range. The Hi detections reveal two major galaxy overdensities located at vrad ∼ 2096 − 7646 km/s and vrad ∼ 10, 000 km/s. The first is associated with the Norma cluster gravitational potential and indicates a substructure in its velocity distribution; the other is a population of background galaxies. In this work, the Norma cluster has 13 cluster members detected in Hi and 130 galaxies from optical surveys. The spatial distribution of cluster members covers a field that is 2/3 × RA, where RA = 2.02 Mpc at cz = 4871 km/s. From the spatial distribution, optical galaxies are densely populated in the central regions, while most galaxies in Hi were detected on the outskirts. From the phase-space diagram, 6 galaxies detected in Hi are found in the virialised region, while the rest of the detections are infalling for the first time. Hi detections that are not yet virialised have asymmetrical morphologies, while virialised detections have truncated gas disks. Most cluster members that were found to have asymmetrical gas disks are also Hi deficient by 0.8 − 1.2 dex but show excess SFR efficiency for the amount of Hi detected. The results demonstrate that the initial phase of galaxy-ICM interactions might be responsible for morphological transformation and enhancement of star formation activity. , Thesis (MSc) -- Faculty of Science, Physics and Electronics, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mophahlane, Koketso Vincent
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/432530 , vital:72878
- Description: Studies reveal that galaxies assemble into clusters as gas-rich, active star-forming disks and eventually settle in the virialized core as quenched early-type galaxies with depleted gas. To examine environmental effects responsible for the quenched population in the cluster core, we exploit the higher sensitivity of the MeerKAT telescope to probe Hi properties of galaxies in the Norma cluster. The Norma cluster is an ideal laboratory for this study since it is a rich and massive cluster of nearby galaxies. The Hi data cube used covers a velocity range of 483 − 11, 113 km/s, with a noise rms sensitivity of 0.09 mJy/beam and an angular resolution of ∼ 14.65′′ × 9.28′′. A total of 25 reliable Hi sources were detected over the entire velocity range. The Hi detections reveal two major galaxy overdensities located at vrad ∼ 2096 − 7646 km/s and vrad ∼ 10, 000 km/s. The first is associated with the Norma cluster gravitational potential and indicates a substructure in its velocity distribution; the other is a population of background galaxies. In this work, the Norma cluster has 13 cluster members detected in Hi and 130 galaxies from optical surveys. The spatial distribution of cluster members covers a field that is 2/3 × RA, where RA = 2.02 Mpc at cz = 4871 km/s. From the spatial distribution, optical galaxies are densely populated in the central regions, while most galaxies in Hi were detected on the outskirts. From the phase-space diagram, 6 galaxies detected in Hi are found in the virialised region, while the rest of the detections are infalling for the first time. Hi detections that are not yet virialised have asymmetrical morphologies, while virialised detections have truncated gas disks. Most cluster members that were found to have asymmetrical gas disks are also Hi deficient by 0.8 − 1.2 dex but show excess SFR efficiency for the amount of Hi detected. The results demonstrate that the initial phase of galaxy-ICM interactions might be responsible for morphological transformation and enhancement of star formation activity. , Thesis (MSc) -- Faculty of Science, Physics and Electronics, 2023
- Full Text:
- Date Issued: 2023-10-13
High-resolution hydraulic modelling as an approach to planning rehabilitation interventions in unchanneled valley-bottom palmiet wetlands: a case study of the Kromme River
- Authors: Langner, Wiebke
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424610 , vital:72168
- Description: This study employs high-resolution hydraulic modelling techniques to inform the planning of rehabilitation interventions in unchanneled valley-bottom palmiet wetlands, using the upper Kromme River wetlands as a case study. It investigates the impact of geomorphic processes on the morphology of the valley, how changes in valley morphology affect the flow characteristics (velocity, stream power, depth) of the river, and how these changes affect the geomorphic dynamics of the wetlands. An aerial LiDAR survey was conducted for a 23km-long reach of the upper Kromme River where the wetlands are situated. A high-resolution (5 m) DTM was created from the LiDAR data to examine the valley morphology. Focusing on three major wetland basins, the relationship between valley morphology and geomorphic processes was examined using high-resolution imagery that accompanied the LiDAR survey and Google Satellite imagery. The hydraulic modelling software HEC-RAS was used to investigate the spatial variation in velocity, stream power, and water depth down the surveyed length of the river. The model outputs provide insight into the effect of valley morphology on flow characteristics. The river appears to have a graded longitudinal profile, such that there is a systematic reduction in slope down its length. Water flowing down the river works, through the processes of erosion and deposition, to control the longitudinal slope, channel planform, and geometry to create a valley with a gentle longitudinal slope (approximately 1%) and a broad, near-horizontal valley-bottom in the mountainous landscape of the Cape Fold Mountains. The overall form of the Kromme River valley and wetlands is primarily a consequence of repeated cycles of cutting and filling. Tributary alluvial fans control the initiation of gully erosion in the wetlands, but their effect is diminished in a downstream direction. Despite a 10-fold increase in discharge down the 23km length of river for a given flood magnitude, there is no significant increase in flow velocity, stream power, or depth in a downstream direction. Consequently, the kinetic energy of the water in the lower wetland basin is surprisingly low. These conditions favour the establishment of palmiet. Flows in eroded reaches are much higher than in non-eroded reaches where discharge is spread across a broad valley bottom. In terms of palmiet establishment and regeneration, this means that areas dominated by depositional processes are best suited to the establishment of palmiet. Based on this information, optimal sites to trial new wetland rehabilitation strategies that employ palmiet were selected. This work supports the importance of understanding the role of geomorphology in wetland structure and dynamics when approaching wetland rehabilitation and is likely to be more sympathetic to natural processes than current interventions. , Thesis (MSc) -- Faculty of Science, Geography, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Langner, Wiebke
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424610 , vital:72168
- Description: This study employs high-resolution hydraulic modelling techniques to inform the planning of rehabilitation interventions in unchanneled valley-bottom palmiet wetlands, using the upper Kromme River wetlands as a case study. It investigates the impact of geomorphic processes on the morphology of the valley, how changes in valley morphology affect the flow characteristics (velocity, stream power, depth) of the river, and how these changes affect the geomorphic dynamics of the wetlands. An aerial LiDAR survey was conducted for a 23km-long reach of the upper Kromme River where the wetlands are situated. A high-resolution (5 m) DTM was created from the LiDAR data to examine the valley morphology. Focusing on three major wetland basins, the relationship between valley morphology and geomorphic processes was examined using high-resolution imagery that accompanied the LiDAR survey and Google Satellite imagery. The hydraulic modelling software HEC-RAS was used to investigate the spatial variation in velocity, stream power, and water depth down the surveyed length of the river. The model outputs provide insight into the effect of valley morphology on flow characteristics. The river appears to have a graded longitudinal profile, such that there is a systematic reduction in slope down its length. Water flowing down the river works, through the processes of erosion and deposition, to control the longitudinal slope, channel planform, and geometry to create a valley with a gentle longitudinal slope (approximately 1%) and a broad, near-horizontal valley-bottom in the mountainous landscape of the Cape Fold Mountains. The overall form of the Kromme River valley and wetlands is primarily a consequence of repeated cycles of cutting and filling. Tributary alluvial fans control the initiation of gully erosion in the wetlands, but their effect is diminished in a downstream direction. Despite a 10-fold increase in discharge down the 23km length of river for a given flood magnitude, there is no significant increase in flow velocity, stream power, or depth in a downstream direction. Consequently, the kinetic energy of the water in the lower wetland basin is surprisingly low. These conditions favour the establishment of palmiet. Flows in eroded reaches are much higher than in non-eroded reaches where discharge is spread across a broad valley bottom. In terms of palmiet establishment and regeneration, this means that areas dominated by depositional processes are best suited to the establishment of palmiet. Based on this information, optimal sites to trial new wetland rehabilitation strategies that employ palmiet were selected. This work supports the importance of understanding the role of geomorphology in wetland structure and dynamics when approaching wetland rehabilitation and is likely to be more sympathetic to natural processes than current interventions. , Thesis (MSc) -- Faculty of Science, Geography, 2023
- Full Text:
- Date Issued: 2023-10-13
HOP abundance affects nuclear pore components and the export of protein and RNA cargo
- Authors: Oladipo, Hannah Oluwakemi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432192 , vital:72850
- Description: Access restricted. Expected release date 2025. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Oladipo, Hannah Oluwakemi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432192 , vital:72850
- Description: Access restricted. Expected release date 2025. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
Identification of novel Arf1 GTPase inhibitors for cancer target validation
- Authors: Mqwathi, Nomxolisi Vuyokasi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424666 , vital:72173
- Description: The key regulators of both anterograde and retrograde vesicular traffic, adenosine diphosphate-ribosylation factors (Arfs), also coordinate various signalling pathways and regulate cellular processes required for cell survival and function. In addition to its role in mediating secretory trafficking in the Golgi apparatus, the involvement of Arf1 in signalling pathways that contribute to the formation and progression of cancer has become apparent, and the overexpression and deregulation of Arf1 activity has been associated with cancer cell invasion, proliferation and metastasis. As with other small GTPases, Arf1 must cycle back and forth between an inactive (GDP-bound) and active (GTP-bound) conformation to carry out its function. However, the cycle of Arf1 inactivation and activation is controlled by Arf GTPase activating proteins (Arf-GAPs) that stimulate Arf1 to hydrolyse the bound GTP to GDP and Arf guanine nucleotide exchange factors (Arf-GEFs) that facilitate GDP for GTP exchange on Arf1, respectively. The identification of Arf1 inhibitors that indirectly disrupt Arf1 function by blocking its interaction with Arf-GAPs or Arf-GEFs has generated interest in their use as possible anti-cancer agents. The suppression of Arf1 activation (by targeting Arf-GEFs) has been investigated as a potential cancer therapeutic target and resulted in inhibitor compounds that have micromolar-range activity against cancer cells and targets and promising results in mouse models, but experience problems with bioavailability when used in vivo. This motivates the search for novel Arf1 inhibitors for validation purposes to question whether Arf1 is a viable target for cancer therapy. The purpose of the study was to employ a recently developed colourimetric screening assay to identify inhibitors of Arf1 activation (Arf-GEF inhibitors) and deactivation (Arf-GAP inhibitors), with a focus on evaluating the potential of Arf1 deactivation as an entirely novel anti-cancer target. The proteins required for the assay (Arf1, Arf-GEF and -GAP domains and a reporter protein, GST-GGA3) were expressed in E. coli. and purified using affinity chromatography. The assay could detect the activation of Arf1 by the catalytic Sec7 domain of the three Arf-GEFs chosen for this study, but reproducibility was compromised by the occasional spontaneous activation of Arf1 in the absence of the Arf-GEFs. By contrast, the assay could reproducibly detect Arf1 deactivation by an Arf-GAP domain (Arf-GAP1GAP) and was subsequently used to screen a library of α-helix mimetics. Thirteen hit compounds with IC50 values ranging from 0.53 to 20.95 μM were found to inhibit Arf-GAP1GAP-mediated stimulation of GTP hydrolysis by Arf1-GTP in this assay format, however, they did not effectively suppress the proliferation of three tested cell lines (HeLa, MCF-7 and MCF-12A). Interestingly, the results obtained from fluorescence microscopy studies suggested that the compounds disrupt Golgi structure and Arf1 localisation, presumably by keeping Arf1 in its active conformation by blocking Arf-GAP1 function. This suggests that the compounds affect Arf1 function in cells, and may be used to explore the feasibility of targeting Arf1 deactivation for anti-cancer purposes in a wider range of cell lines and experiments. It has been reported that Arf-GAP1 inhibition is associated with the suppression of cell migration, and the potential of the compounds as metastasis inhibitors may also be explored. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mqwathi, Nomxolisi Vuyokasi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424666 , vital:72173
- Description: The key regulators of both anterograde and retrograde vesicular traffic, adenosine diphosphate-ribosylation factors (Arfs), also coordinate various signalling pathways and regulate cellular processes required for cell survival and function. In addition to its role in mediating secretory trafficking in the Golgi apparatus, the involvement of Arf1 in signalling pathways that contribute to the formation and progression of cancer has become apparent, and the overexpression and deregulation of Arf1 activity has been associated with cancer cell invasion, proliferation and metastasis. As with other small GTPases, Arf1 must cycle back and forth between an inactive (GDP-bound) and active (GTP-bound) conformation to carry out its function. However, the cycle of Arf1 inactivation and activation is controlled by Arf GTPase activating proteins (Arf-GAPs) that stimulate Arf1 to hydrolyse the bound GTP to GDP and Arf guanine nucleotide exchange factors (Arf-GEFs) that facilitate GDP for GTP exchange on Arf1, respectively. The identification of Arf1 inhibitors that indirectly disrupt Arf1 function by blocking its interaction with Arf-GAPs or Arf-GEFs has generated interest in their use as possible anti-cancer agents. The suppression of Arf1 activation (by targeting Arf-GEFs) has been investigated as a potential cancer therapeutic target and resulted in inhibitor compounds that have micromolar-range activity against cancer cells and targets and promising results in mouse models, but experience problems with bioavailability when used in vivo. This motivates the search for novel Arf1 inhibitors for validation purposes to question whether Arf1 is a viable target for cancer therapy. The purpose of the study was to employ a recently developed colourimetric screening assay to identify inhibitors of Arf1 activation (Arf-GEF inhibitors) and deactivation (Arf-GAP inhibitors), with a focus on evaluating the potential of Arf1 deactivation as an entirely novel anti-cancer target. The proteins required for the assay (Arf1, Arf-GEF and -GAP domains and a reporter protein, GST-GGA3) were expressed in E. coli. and purified using affinity chromatography. The assay could detect the activation of Arf1 by the catalytic Sec7 domain of the three Arf-GEFs chosen for this study, but reproducibility was compromised by the occasional spontaneous activation of Arf1 in the absence of the Arf-GEFs. By contrast, the assay could reproducibly detect Arf1 deactivation by an Arf-GAP domain (Arf-GAP1GAP) and was subsequently used to screen a library of α-helix mimetics. Thirteen hit compounds with IC50 values ranging from 0.53 to 20.95 μM were found to inhibit Arf-GAP1GAP-mediated stimulation of GTP hydrolysis by Arf1-GTP in this assay format, however, they did not effectively suppress the proliferation of three tested cell lines (HeLa, MCF-7 and MCF-12A). Interestingly, the results obtained from fluorescence microscopy studies suggested that the compounds disrupt Golgi structure and Arf1 localisation, presumably by keeping Arf1 in its active conformation by blocking Arf-GAP1 function. This suggests that the compounds affect Arf1 function in cells, and may be used to explore the feasibility of targeting Arf1 deactivation for anti-cancer purposes in a wider range of cell lines and experiments. It has been reported that Arf-GAP1 inhibition is associated with the suppression of cell migration, and the potential of the compounds as metastasis inhibitors may also be explored. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
Identification of novel therapeutic agents targeting Kaposi's sarcoma-associated herpesvirus (KSHV) lytic replication
- Authors: Okpara, Michael Obinna
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432181 , vital:72849
- Description: Access restricted. Expected release date 2025. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Okpara, Michael Obinna
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432181 , vital:72849
- Description: Access restricted. Expected release date 2025. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
Implementing a sexual and reproductive citizenship intervention refinement instrument for youth sexuality education: a formative evaluation
- Authors: Mthethwa, Thobile
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425008 , vital:72201
- Description: While Out of School sexuality education (SE) programmes in South Africa have attempted to bridge the gap in the number of young people who receive SE, there is still a large number of youth between the age groups of 15 to 24 years who lack adequate sexual knowledge. The manner in which sex education is taught and its accessibility is accompanied by challenges, in particular in relation to empowerment. To better understand the effectiveness of sexual education programmes, evaluations of their content is needed. Therefore, the purpose of this study was to investigate whether and how an Out of school SE programme run by Partners in Sexual Health (PSH) promotes understandings of sexual and reproductive citizenship. A formative evaluation of their sexual and reproductive health and rights (SRHR) facilitator’s manual was conducted (owing to COVID the actual programme was not run in the year data for this thesis were collected). To help perform the formative evaluation, the feminist sexual and reproductive citizenship (SRC) framework as conceptualized by Macleod and Vincent (2014) was used. The SRC framework consists of five key principles that, it is suggested, need to be adopted for SE programmes to be inclusive, namely, citizenship as status and practice, differentiated citizenship, private and public interstice, and politics of recognition, redistribution and reparation. An additional principle of inclusive and process-based educational practices was added into the five key principles. To analyse data, template analysis was used which enabled the researcher to create a priori of themes using the Masizixhobise toolkit which is informed by the SRC framework. Findings from this study reveal the interconnectedness between the different citizenship principles. Moreover, while the PSH SRHR programme promotes principles of the SRC framework, there are aspects of the SRC that are lacking from the programme. Therefore, the SRHR manual needs to take into account a spectrum of issues which include but are not limited to the incorporation of sexually diverse differently-abled individuals' sexual experiences and challenges when it comes to accessing SE. This means for SE programmes to achieve inclusivity and to be empowering, they need to encourage individuals to be agentic beings, engage in informed decision-making and encourage young people to take up their rights. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mthethwa, Thobile
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425008 , vital:72201
- Description: While Out of School sexuality education (SE) programmes in South Africa have attempted to bridge the gap in the number of young people who receive SE, there is still a large number of youth between the age groups of 15 to 24 years who lack adequate sexual knowledge. The manner in which sex education is taught and its accessibility is accompanied by challenges, in particular in relation to empowerment. To better understand the effectiveness of sexual education programmes, evaluations of their content is needed. Therefore, the purpose of this study was to investigate whether and how an Out of school SE programme run by Partners in Sexual Health (PSH) promotes understandings of sexual and reproductive citizenship. A formative evaluation of their sexual and reproductive health and rights (SRHR) facilitator’s manual was conducted (owing to COVID the actual programme was not run in the year data for this thesis were collected). To help perform the formative evaluation, the feminist sexual and reproductive citizenship (SRC) framework as conceptualized by Macleod and Vincent (2014) was used. The SRC framework consists of five key principles that, it is suggested, need to be adopted for SE programmes to be inclusive, namely, citizenship as status and practice, differentiated citizenship, private and public interstice, and politics of recognition, redistribution and reparation. An additional principle of inclusive and process-based educational practices was added into the five key principles. To analyse data, template analysis was used which enabled the researcher to create a priori of themes using the Masizixhobise toolkit which is informed by the SRC framework. Findings from this study reveal the interconnectedness between the different citizenship principles. Moreover, while the PSH SRHR programme promotes principles of the SRC framework, there are aspects of the SRC that are lacking from the programme. Therefore, the SRHR manual needs to take into account a spectrum of issues which include but are not limited to the incorporation of sexually diverse differently-abled individuals' sexual experiences and challenges when it comes to accessing SE. This means for SE programmes to achieve inclusivity and to be empowering, they need to encourage individuals to be agentic beings, engage in informed decision-making and encourage young people to take up their rights. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-10-13
In-silico investigation of the effects of genetic mutations on the structural dynamics of thiopurine s-methyltransferase and their implications on the metabolism of 6-mercaptopurine
- Authors: Mwaniki, Rehema Mukami
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/432553 , vital:72880
- Description: Thiopurine S-methyltransferase (TPMT) is a cytosolic enzyme that catalyzes the S-methylation of aromatic and heterocyclic sulfhydryl compounds such as 6-mercaptopurine (6MP), 6-thioguanine (6TG) and azathioprine (AZA) which is first converted to 6MP through reduction by glutathione S- transferases (GST). The compounds, generally referred to as thiopurines, are immunosuppressants used to treat childhood acute lymphoblastic leukemia (ALL), autoimmune disorders and transplant rejection. Thiopurines are prodrugs which require metabolic activation to give thioguanine nucleotides that exert their cytotoxic effects by incorporation into DNA or inhibiting purine synthesis. The methylation reaction by TPMT utilizing S-adenosylmethionine (SAM) as the methyl donor prevents their conversion to these toxic compounds. The catalytic activity of TPMT in metabolising these compounds has been associated with occurrence of genetic variations. The variations that result to missense mutations cause amino-acid changes and in turn alter the polypeptide sequence of the protein. This could alter functionality and structural dynamics of the enzyme. This study sought to understand the underlying mechanism by which 7 specially selected mutations impede metabolic activity of the enzyme on 6-MP using in silico techniques. VAPOR and PredictSNP were used to predict the effects of single nucleotide polymorphisms (SNPs) on the stability and function of the enzyme. Of the 7 mutations, only H227Q was predicted to be functionally benign while the rest (L49S, L69V, A80P, R163H, R163C and R163P) were predicted to be deleterious or associated with disease. All the SNPs were predicted to destabilize the enzyme. Molecular dynamics (MD) simulations were preformed to mimic the behaviour of the apo, holo and drug-bound WT and mutant enzymes in vivo. This was followed by post-MD analysis to identify changes in the local and global motions of the protein in the presence of mutations and changes in intra-protein communication networks through contact map and centrality metrics calculations. RMSD and Rg analyses were performed to assess changes in global motions and compactness of the enzyme in the apo, holo and drug-bound states and in the presence of mutations. These revealed that binding of the ligand had a stabilizing effect on the WT enzyme evident from more steady trends from the analyses across trajectories in the holo and drug-bound enzymes compared to the apoenzyme. The occurrence of mutations had an effect on the global motions and compactness of the enzyme across the trajectories. Most mutations resulted in destabilized systems and less compact structures shown by unsteady RMSD and Rg across trajectories respectively. The drugbound systems appeared to be more stable in most of the systems meaning that the binding of 6MP stabilized the enzyme regardless of the presence of a mutation. RMSF analysis recorded local changes in residue flexibility due to the presence of mutations in all the systems. All the drug-bound mutant systems lost flexibility on the αAhelix which caps the active site. This could have an effect on drug binding and result to defective drug metabolism. The A80P mutation resulted to a more rigid structure from both global and local motions compared to the WT enzyme which could be associated with its nearly loss of function in vivo and in vitro. Dynamic cross correlation calculations were performed to assess how the atoms moved together. Correlated, anti-correlated and areas of no correlations were recorded in all the systems and in similar places when compared to each other. This meant that occurrence of mutations had no effect on how the atoms moved together. Contact map analysis showed that occurrence of mutations caused changes in interactions around the positions where the mutations occurred, which could have an effect on protein structural dynamics. The A80P substitution which occurred on the surface away from the binding site was identified as an allosteric mutation that resulted to changes in the catalytic site. Contact maps for the drug-cofactor complex in the mutant systems in comparison with the WT protein revealed changes that could suggest reorientation of the drug at the catalytic site. This could be an implication to altered drug metabolism. Eigenvector centrality (EC) and betweenness centrality (BC) for the most equilibrated portions of the trajectories were calculated for all the studied systems to identify residues connected to the most important residues and those that were spanned the most in shortest paths connecting other residues. Areas that scored highest in these metrics where mostly found in regions surrounding the catalytic site. Top 5% centrality hubs calculations showed loss of major hubs due to mutations with gaining of new ones. This means that mutations affected communication networks within the protein. The gained hubs were in areas close-by the lost ones which could have been an attempt of the protein to accommodate the mutations. Persistent top 5% BC hubs were identified at positions 90 and 151 while one persistent top 5% EC hub was identified at position 70. This positions play important roles in shaping the catalytic site and are in direct contact with the ligands. It was concluded that in silico techniques and analysis applied in this study revealed possible mechanisms in which genetic variations affected the structural dynamics of TMPT enzyme an affecte 6MP metabolism. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mwaniki, Rehema Mukami
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/432553 , vital:72880
- Description: Thiopurine S-methyltransferase (TPMT) is a cytosolic enzyme that catalyzes the S-methylation of aromatic and heterocyclic sulfhydryl compounds such as 6-mercaptopurine (6MP), 6-thioguanine (6TG) and azathioprine (AZA) which is first converted to 6MP through reduction by glutathione S- transferases (GST). The compounds, generally referred to as thiopurines, are immunosuppressants used to treat childhood acute lymphoblastic leukemia (ALL), autoimmune disorders and transplant rejection. Thiopurines are prodrugs which require metabolic activation to give thioguanine nucleotides that exert their cytotoxic effects by incorporation into DNA or inhibiting purine synthesis. The methylation reaction by TPMT utilizing S-adenosylmethionine (SAM) as the methyl donor prevents their conversion to these toxic compounds. The catalytic activity of TPMT in metabolising these compounds has been associated with occurrence of genetic variations. The variations that result to missense mutations cause amino-acid changes and in turn alter the polypeptide sequence of the protein. This could alter functionality and structural dynamics of the enzyme. This study sought to understand the underlying mechanism by which 7 specially selected mutations impede metabolic activity of the enzyme on 6-MP using in silico techniques. VAPOR and PredictSNP were used to predict the effects of single nucleotide polymorphisms (SNPs) on the stability and function of the enzyme. Of the 7 mutations, only H227Q was predicted to be functionally benign while the rest (L49S, L69V, A80P, R163H, R163C and R163P) were predicted to be deleterious or associated with disease. All the SNPs were predicted to destabilize the enzyme. Molecular dynamics (MD) simulations were preformed to mimic the behaviour of the apo, holo and drug-bound WT and mutant enzymes in vivo. This was followed by post-MD analysis to identify changes in the local and global motions of the protein in the presence of mutations and changes in intra-protein communication networks through contact map and centrality metrics calculations. RMSD and Rg analyses were performed to assess changes in global motions and compactness of the enzyme in the apo, holo and drug-bound states and in the presence of mutations. These revealed that binding of the ligand had a stabilizing effect on the WT enzyme evident from more steady trends from the analyses across trajectories in the holo and drug-bound enzymes compared to the apoenzyme. The occurrence of mutations had an effect on the global motions and compactness of the enzyme across the trajectories. Most mutations resulted in destabilized systems and less compact structures shown by unsteady RMSD and Rg across trajectories respectively. The drugbound systems appeared to be more stable in most of the systems meaning that the binding of 6MP stabilized the enzyme regardless of the presence of a mutation. RMSF analysis recorded local changes in residue flexibility due to the presence of mutations in all the systems. All the drug-bound mutant systems lost flexibility on the αAhelix which caps the active site. This could have an effect on drug binding and result to defective drug metabolism. The A80P mutation resulted to a more rigid structure from both global and local motions compared to the WT enzyme which could be associated with its nearly loss of function in vivo and in vitro. Dynamic cross correlation calculations were performed to assess how the atoms moved together. Correlated, anti-correlated and areas of no correlations were recorded in all the systems and in similar places when compared to each other. This meant that occurrence of mutations had no effect on how the atoms moved together. Contact map analysis showed that occurrence of mutations caused changes in interactions around the positions where the mutations occurred, which could have an effect on protein structural dynamics. The A80P substitution which occurred on the surface away from the binding site was identified as an allosteric mutation that resulted to changes in the catalytic site. Contact maps for the drug-cofactor complex in the mutant systems in comparison with the WT protein revealed changes that could suggest reorientation of the drug at the catalytic site. This could be an implication to altered drug metabolism. Eigenvector centrality (EC) and betweenness centrality (BC) for the most equilibrated portions of the trajectories were calculated for all the studied systems to identify residues connected to the most important residues and those that were spanned the most in shortest paths connecting other residues. Areas that scored highest in these metrics where mostly found in regions surrounding the catalytic site. Top 5% centrality hubs calculations showed loss of major hubs due to mutations with gaining of new ones. This means that mutations affected communication networks within the protein. The gained hubs were in areas close-by the lost ones which could have been an attempt of the protein to accommodate the mutations. Persistent top 5% BC hubs were identified at positions 90 and 151 while one persistent top 5% EC hub was identified at position 70. This positions play important roles in shaping the catalytic site and are in direct contact with the ligands. It was concluded that in silico techniques and analysis applied in this study revealed possible mechanisms in which genetic variations affected the structural dynamics of TMPT enzyme an affecte 6MP metabolism. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
International students’ experiences of othering in tertiary education in South Africa: an exploratory study
- Authors: Lobakeng, Tsholofelo
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424986 , vital:72199
- Description: Despite rising cases of xenophobia in South Africa, international students remain committed to enrolling in its universities. Surprisingly, there is limited research looking into xenophobia in tertiary institutions. Therefore, the present study aimed to contribute to the scarcity of knowledge on the experiences of international students in South Africa. Thus, the study explored experiences of Othering among international students in tertiary education in South Africa and how they make sense of these experiences. Purposive and snowballing sampling techniques were employed to recruit international students (N=5) from Botswana, China, Zambia, and Zimbabwe. Data was collected through semi-structured, face-to-face online interviews. Participants reported experiencing a variety of non-violent forms of Othering, such as feeling excluded due to the intentional use of local languages in both classroom and social settings; being rejected by local students who refused to work with them; and being accused of stealing opportunities from local students. At an institutional level, participants reported systemic Othering rooted in unsupportive policies and practices that led to a negative and oppressive environment. The findings support previous research studies that purport the Othering of international students in higher education in South Africa mainly manifests through non-violent and covert forms. Moreover, participants attributed Othering of immigrants to racism, a perceived lack of exposure to diversity among locals, perceived lack of compassion for immigrants, and the tendency to scapegoat immigrants for the lack of employment opportunities in the country. The findings underscore the intricate nature of Othering and the need for further research to gain a greater understanding of this complex phenomenon. Furthermore, the findings highlight the importance of implementing effective strategies of inclusion and integration of international students at these institutions of higher learning. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Lobakeng, Tsholofelo
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424986 , vital:72199
- Description: Despite rising cases of xenophobia in South Africa, international students remain committed to enrolling in its universities. Surprisingly, there is limited research looking into xenophobia in tertiary institutions. Therefore, the present study aimed to contribute to the scarcity of knowledge on the experiences of international students in South Africa. Thus, the study explored experiences of Othering among international students in tertiary education in South Africa and how they make sense of these experiences. Purposive and snowballing sampling techniques were employed to recruit international students (N=5) from Botswana, China, Zambia, and Zimbabwe. Data was collected through semi-structured, face-to-face online interviews. Participants reported experiencing a variety of non-violent forms of Othering, such as feeling excluded due to the intentional use of local languages in both classroom and social settings; being rejected by local students who refused to work with them; and being accused of stealing opportunities from local students. At an institutional level, participants reported systemic Othering rooted in unsupportive policies and practices that led to a negative and oppressive environment. The findings support previous research studies that purport the Othering of international students in higher education in South Africa mainly manifests through non-violent and covert forms. Moreover, participants attributed Othering of immigrants to racism, a perceived lack of exposure to diversity among locals, perceived lack of compassion for immigrants, and the tendency to scapegoat immigrants for the lack of employment opportunities in the country. The findings underscore the intricate nature of Othering and the need for further research to gain a greater understanding of this complex phenomenon. Furthermore, the findings highlight the importance of implementing effective strategies of inclusion and integration of international students at these institutions of higher learning. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-10-13
Investigating pedagogical practices of English First Additional Language educators in Grade 12 short stories: a case study
- Authors: Jabe, Sizwe
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424052 , vital:72119
- Description: The focus of this study was to investigate pedagogical practices of English First Additional Language educators in teaching Grade 12 short stories. An interpretive qualitative case study of three educators from three high schools in Chris Hani West district, in Eastern Cape were purposefully selected. Lesson observations, semi-structured interviews, and document analysis (lesson plans) with three English FAL educators were used to collect data. Shulman’s (1986) Pedagogical Content Knowledge was used as the theoretical framework and analytical tool for the study. Data revealed ineffective teaching strategies and on-the-surface subject matter knowledge that hampers the critical teaching of short stories. It also showed that educators have limited knowledge of learners’ learning difficulties and how to address them. The study recommends less teacher talk that was observed in many classes, to be replaced by extended discussions on the part of the learners. Educators should establish a variety of contemporary teaching strategies which put critical thinking and active learning before examination preparation. Lastly, educators, in their teaching of short stories, should consult various resources and attend content workshops to keep subject knowledge up to date. , Thesis (MEd) -- Faculty of Humanities, Study of Englishes of Africa, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Jabe, Sizwe
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424052 , vital:72119
- Description: The focus of this study was to investigate pedagogical practices of English First Additional Language educators in teaching Grade 12 short stories. An interpretive qualitative case study of three educators from three high schools in Chris Hani West district, in Eastern Cape were purposefully selected. Lesson observations, semi-structured interviews, and document analysis (lesson plans) with three English FAL educators were used to collect data. Shulman’s (1986) Pedagogical Content Knowledge was used as the theoretical framework and analytical tool for the study. Data revealed ineffective teaching strategies and on-the-surface subject matter knowledge that hampers the critical teaching of short stories. It also showed that educators have limited knowledge of learners’ learning difficulties and how to address them. The study recommends less teacher talk that was observed in many classes, to be replaced by extended discussions on the part of the learners. Educators should establish a variety of contemporary teaching strategies which put critical thinking and active learning before examination preparation. Lastly, educators, in their teaching of short stories, should consult various resources and attend content workshops to keep subject knowledge up to date. , Thesis (MEd) -- Faculty of Humanities, Study of Englishes of Africa, 2023
- Full Text:
- Date Issued: 2023-10-13
Investigation into methods of recovering campylobacter spp. from river water samples
- Authors: Ngoni, Nandipha
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424177 , vital:72130
- Description: Campylobacter species are slender, gram-negative, rod-shaped, spiral- or curved-shaped with single or pairs of flagella. They are the leading cause of diarrheal disease globally, consumption of and contact with water contaminated by faeces is a major risk factor for transmission of these organisms to humans. Rivers used for recreation and domestic and agricultural activities represent all the risk factors for Campylobacter spp. pollution and human exposure. Campylobacter spp. However, effective methods to recover Campylobacter spp. from river water samples are lacking, indicating the need for the development of more efficient methods of detection and isolation of these organisms from environmental water samples. Campylobacter detection in a water sample is critical to ascertain potential risks to humans. The aim of this study was to determine a suitable method for the detection of Campylobacter spp. from river water samples and the objectives were to (i) to evaluate the performance of different methods used for the recovery of Campylobacter spp. from environmental water samples based on Campylobacter colony count and PCR identification results, (ii) isolate and enumerate Campylobacter cells from river water samples, and (iii) identify Campylobacter spp. in river water samples. The Bloukrans River was chosen for this study because it is suspected to be contaminated by faecal inputs from nearby informal settlements without adequate sanitation, as well as untreated/insufficiently treated effluents from nearby wastewater treatment plants. First, the physicochemical quality of the river water and the presence of faecal contamination were assessed to confirm suitability for Campylobacter spp. survival and presence. Then different approaches to sample, concentrate and recover Campylobacter spp. from river water samples were assessed. The different methods assessed were (i) direct enrichment of water samples without prior concentration, (ii) prior concentration of water samples by centrifugation followed by membrane filtration of supernatant, and after that, pooling the residue and pellet together for enrichment, (iii) sampling by the Moore Swab technique. For all three methods, enrichment in Bolton broth supplemented with Bolton antibiotics was conducted. This was followed by plating on modified cefoperazone charcoal deoxycholate agar (mCCDA) and incubation under a microaerophilic atmosphere at 42°C for 48 h. Colony morphology, Gram staining and polymerase chain reaction (PCR) were used to identify and characterize the microorganisms. The growth of blue colonies on the mFc agar surface confirmed presence and faecal pollution of the Bloukrans River. The physicochemical properties, based on the range of pH measured at different sites of the river (between acidic 3.45 to 6.42 and alkaline 7.2 to 8.74) indicate that Campylobacter spp. can thrive in the river. Based on the results from enumeration and sequencing of colonies recovered by each method, it was discovered that the most suitable method to recover Campylobacter spp. from river water samples is by prior centrifugation (14,000 × g for 30 minutes) followed by membrane filtration of the supernatant, and subsequent pooling of the residue and pellet. The pooled residue and pellet might have increased Campylobacter spp. concentrations aiding more growth during the enrichment of Campylobacter spp. from the river water samples. Results from enumerating Campylobacter spp. cells from river water samples indicate that Campylobacter spp. are present in Bloukrans River. The sequence obtained from the PCR product indicates that the species found were Campylobacter jejuni (96% homology as evaluated by BLAST). This study provided a procedure effective for obtaining a satisfactory quantitative recovery of Campylobacter spp. from environmental waters, a critical need for quantitative microbial risk assessment studies. , Thesis (MSc) -- Faculty of Science, Institute for Water Research, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Ngoni, Nandipha
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424177 , vital:72130
- Description: Campylobacter species are slender, gram-negative, rod-shaped, spiral- or curved-shaped with single or pairs of flagella. They are the leading cause of diarrheal disease globally, consumption of and contact with water contaminated by faeces is a major risk factor for transmission of these organisms to humans. Rivers used for recreation and domestic and agricultural activities represent all the risk factors for Campylobacter spp. pollution and human exposure. Campylobacter spp. However, effective methods to recover Campylobacter spp. from river water samples are lacking, indicating the need for the development of more efficient methods of detection and isolation of these organisms from environmental water samples. Campylobacter detection in a water sample is critical to ascertain potential risks to humans. The aim of this study was to determine a suitable method for the detection of Campylobacter spp. from river water samples and the objectives were to (i) to evaluate the performance of different methods used for the recovery of Campylobacter spp. from environmental water samples based on Campylobacter colony count and PCR identification results, (ii) isolate and enumerate Campylobacter cells from river water samples, and (iii) identify Campylobacter spp. in river water samples. The Bloukrans River was chosen for this study because it is suspected to be contaminated by faecal inputs from nearby informal settlements without adequate sanitation, as well as untreated/insufficiently treated effluents from nearby wastewater treatment plants. First, the physicochemical quality of the river water and the presence of faecal contamination were assessed to confirm suitability for Campylobacter spp. survival and presence. Then different approaches to sample, concentrate and recover Campylobacter spp. from river water samples were assessed. The different methods assessed were (i) direct enrichment of water samples without prior concentration, (ii) prior concentration of water samples by centrifugation followed by membrane filtration of supernatant, and after that, pooling the residue and pellet together for enrichment, (iii) sampling by the Moore Swab technique. For all three methods, enrichment in Bolton broth supplemented with Bolton antibiotics was conducted. This was followed by plating on modified cefoperazone charcoal deoxycholate agar (mCCDA) and incubation under a microaerophilic atmosphere at 42°C for 48 h. Colony morphology, Gram staining and polymerase chain reaction (PCR) were used to identify and characterize the microorganisms. The growth of blue colonies on the mFc agar surface confirmed presence and faecal pollution of the Bloukrans River. The physicochemical properties, based on the range of pH measured at different sites of the river (between acidic 3.45 to 6.42 and alkaline 7.2 to 8.74) indicate that Campylobacter spp. can thrive in the river. Based on the results from enumeration and sequencing of colonies recovered by each method, it was discovered that the most suitable method to recover Campylobacter spp. from river water samples is by prior centrifugation (14,000 × g for 30 minutes) followed by membrane filtration of the supernatant, and subsequent pooling of the residue and pellet. The pooled residue and pellet might have increased Campylobacter spp. concentrations aiding more growth during the enrichment of Campylobacter spp. from the river water samples. Results from enumerating Campylobacter spp. cells from river water samples indicate that Campylobacter spp. are present in Bloukrans River. The sequence obtained from the PCR product indicates that the species found were Campylobacter jejuni (96% homology as evaluated by BLAST). This study provided a procedure effective for obtaining a satisfactory quantitative recovery of Campylobacter spp. from environmental waters, a critical need for quantitative microbial risk assessment studies. , Thesis (MSc) -- Faculty of Science, Institute for Water Research, 2023
- Full Text:
- Date Issued: 2023-10-13
InVisible freedom fighter: a critical analysis of portrayals of women in archival photographs, independence monuments and contemporary art in Zambia (Northern Rhodesia) and Zimbabwe (Southern Rhodesia)
- Authors: Kalichini, Gladys Melina
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432433 , vital:72870 , DOI 10.21504/10962/432433
- Description: This doctoral dissertation in art history develops a notion of invisibility by critically analysing processes in which narratives about women are either concealed or uncovered in visual portrayals relating to the independence of Zambia (former Northern Rhodesia) and Zimbabwe (previously Southern Rhodesia). This study concentrates on three main visual categories that include archival photographs, national monuments, and visual art. It critically engages with concepts of memory and history through a framework of gender. The concept of invisibility developed in this thesis articulates a dynamic process in which independence narratives evolve over time, sometimes revealing memories associated with women and at other times rendering women invisible. National liberation in many African states is dominantly accredited to the political parties that were in power at the time of independence. In Zambia, the United National Independence Party (UNIP) is acknowledged for spearheading efforts to overthrow the colonial administration, while in Zimbabwe it is the Zimbabwe African National Union – Patriotic Front (ZANU – PF). Both political parties were headed by men, and the majority of their memberships was also comprised of men; as such, the dominant narratives largely illuminate the stories of men associated with these political parties. The overarching argument of this doctoral dissertation is that there is a gender bias inherent in dominant independence struggles narratives that are communicated through cultural heritage sites such as monuments and archives. In this study, art and art making inform theory as the methodological approach takes the direction in which selected artworks and visual materials are employed as a starting point of considering concepts that relate to the visibilities of stories about women. This approach cogitates the function of art, visual culture, and art history in the production of knowledges that foster in-depth understandings of concepts that explain social phenomena such as historical erasure. This doctoral dissertation in art history is divided into two parts, A and B, that conceptually complement each other. In section A which comprises of chapters one and two, the study develops an alternative visual archive that surveys the involvements of six specific women in the attainment of national independence in their respective countries, and critically analyses the Freedom Statue in Zambia and the National Heroes Acre in Zimbabwe as monuments dedicated to commemorating the independence struggle in the two countries. In Chapters three to five which form the second section of this dissertation, the emphasis of the discussion is on how selected visual artworks of three selected artists disrupt, counter or engage with dominant historical accounts that either exclude or marginalise narratives about women. The three artists include myself, Gladys Kalichini, and Zimbabwean born artists Kudzanai Chiurai and Gresham Tapiwa Nyaude. This thesis offers a culturally rich conversation about visual representations of social, political and cultural roles women performed in the colonial times in Northern and Southern Rhodesia and gives insight into the evolution of the luminosity of contemporary performances of women’s social collectives in Zambia and Zimbabwe. , Thesis (PhD) -- Faculty of Humanities, Fine Art, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Kalichini, Gladys Melina
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432433 , vital:72870 , DOI 10.21504/10962/432433
- Description: This doctoral dissertation in art history develops a notion of invisibility by critically analysing processes in which narratives about women are either concealed or uncovered in visual portrayals relating to the independence of Zambia (former Northern Rhodesia) and Zimbabwe (previously Southern Rhodesia). This study concentrates on three main visual categories that include archival photographs, national monuments, and visual art. It critically engages with concepts of memory and history through a framework of gender. The concept of invisibility developed in this thesis articulates a dynamic process in which independence narratives evolve over time, sometimes revealing memories associated with women and at other times rendering women invisible. National liberation in many African states is dominantly accredited to the political parties that were in power at the time of independence. In Zambia, the United National Independence Party (UNIP) is acknowledged for spearheading efforts to overthrow the colonial administration, while in Zimbabwe it is the Zimbabwe African National Union – Patriotic Front (ZANU – PF). Both political parties were headed by men, and the majority of their memberships was also comprised of men; as such, the dominant narratives largely illuminate the stories of men associated with these political parties. The overarching argument of this doctoral dissertation is that there is a gender bias inherent in dominant independence struggles narratives that are communicated through cultural heritage sites such as monuments and archives. In this study, art and art making inform theory as the methodological approach takes the direction in which selected artworks and visual materials are employed as a starting point of considering concepts that relate to the visibilities of stories about women. This approach cogitates the function of art, visual culture, and art history in the production of knowledges that foster in-depth understandings of concepts that explain social phenomena such as historical erasure. This doctoral dissertation in art history is divided into two parts, A and B, that conceptually complement each other. In section A which comprises of chapters one and two, the study develops an alternative visual archive that surveys the involvements of six specific women in the attainment of national independence in their respective countries, and critically analyses the Freedom Statue in Zambia and the National Heroes Acre in Zimbabwe as monuments dedicated to commemorating the independence struggle in the two countries. In Chapters three to five which form the second section of this dissertation, the emphasis of the discussion is on how selected visual artworks of three selected artists disrupt, counter or engage with dominant historical accounts that either exclude or marginalise narratives about women. The three artists include myself, Gladys Kalichini, and Zimbabwean born artists Kudzanai Chiurai and Gresham Tapiwa Nyaude. This thesis offers a culturally rich conversation about visual representations of social, political and cultural roles women performed in the colonial times in Northern and Southern Rhodesia and gives insight into the evolution of the luminosity of contemporary performances of women’s social collectives in Zambia and Zimbabwe. , Thesis (PhD) -- Faculty of Humanities, Fine Art, 2023
- Full Text:
- Date Issued: 2023-10-13
Jazz pedagogical strategies: an A/R/Tographic investigation into the implementation of the South African jazz CAPS syllabus
- Authors: Rungan, Natalie
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432488 , vital:72875 , DOI 10.21504/10962/432488
- Description: The Jazz stream of the Curriculum and Assessment Policy Statement Further Education and Training music curriculum was introduced in South Africa in 2012 (DBE, 2011a). Despite the intentions of the government to promote diversity, social transformation, and inclusion, subject music is still weighted towards Western Art Music, perpetuating past biases of a Eurocentric model for music education. This study, which uses a mixed-method approach, seeks to create strategies to advance Jazz education in South Africa through an a/r/tographic analysis of the author’s Jazz pedagogical methods at Durban High School in KwaZulu Natal, South Africa. Key approaches include curriculum theory, currere, a/r/tography, among others. After reviewing Jazz pedagogy in the U.S.A. and South Africa as a starting point, using Pinar’s (1994) method of currere, the author demonstrates how past personal music educational processes have led to present Jazz pedagogical methods. Six original compositions were written that outline the influences that infused these methods and added to the creative output related to this research. Interviews were conducted with key stakeholders in the Jazz community to gain perspective about the current state of Jazz education, and with students to provide insight into their reactions to the Jazz stream of CAPS. This presents new information about the curriculum from a learners’ perspective. Ethical clearance for research with children was sought and received (Appendix A). Findings show that the ability of learners to recognise the value in, and identity relating to, their African culture through Jazz points to a pivotal departure from previous Eurocentric music education models. However, despite South Africa being positioned as one of the only countries offering Jazz as a subject choice to high school learners, the selection of Jazz in the subject of Music remains underutilised. This study concludes that for Jazz education to advance in South African high schools, there needs to be intentional engagement with Jazz professionals at the high school level. , Thesis (PhD) -- Faculty of Humanities, Music and Musicology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Rungan, Natalie
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432488 , vital:72875 , DOI 10.21504/10962/432488
- Description: The Jazz stream of the Curriculum and Assessment Policy Statement Further Education and Training music curriculum was introduced in South Africa in 2012 (DBE, 2011a). Despite the intentions of the government to promote diversity, social transformation, and inclusion, subject music is still weighted towards Western Art Music, perpetuating past biases of a Eurocentric model for music education. This study, which uses a mixed-method approach, seeks to create strategies to advance Jazz education in South Africa through an a/r/tographic analysis of the author’s Jazz pedagogical methods at Durban High School in KwaZulu Natal, South Africa. Key approaches include curriculum theory, currere, a/r/tography, among others. After reviewing Jazz pedagogy in the U.S.A. and South Africa as a starting point, using Pinar’s (1994) method of currere, the author demonstrates how past personal music educational processes have led to present Jazz pedagogical methods. Six original compositions were written that outline the influences that infused these methods and added to the creative output related to this research. Interviews were conducted with key stakeholders in the Jazz community to gain perspective about the current state of Jazz education, and with students to provide insight into their reactions to the Jazz stream of CAPS. This presents new information about the curriculum from a learners’ perspective. Ethical clearance for research with children was sought and received (Appendix A). Findings show that the ability of learners to recognise the value in, and identity relating to, their African culture through Jazz points to a pivotal departure from previous Eurocentric music education models. However, despite South Africa being positioned as one of the only countries offering Jazz as a subject choice to high school learners, the selection of Jazz in the subject of Music remains underutilised. This study concludes that for Jazz education to advance in South African high schools, there needs to be intentional engagement with Jazz professionals at the high school level. , Thesis (PhD) -- Faculty of Humanities, Music and Musicology, 2023
- Full Text:
- Date Issued: 2023-10-13
Just stories?: Epistemic (in)justice and everyday resistance in the digital stories of family literacy practices by Grade 1-5 workers at a South African University
- Authors: Viedge, Jane Margaret
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/432308 , vital:72860
- Description: This thesis sets out to establish in what ways digital storytelling (DST) revealed instances of epistemic (in)justices inherent in the family literacy intervention experiences of four Black, working-class parents employed at a South African University1. Additionally, it explores how DST might be used by the participants (self-labelled the Storytelling Family Literacy - SFL Advocates) to correct any harm done. The context for the research is based on the deep-rooted harms of Bantu education in which Black South Africans were denied equal access to resources such as literacy practices. I investigated these aims by using the theories of DST, Communication for Social Change (C4SC) and epistemic (in)justice. As a participatory media practice supporting communications in marginalised communities, DST’s broad purpose is to assist these communities in telling stories of their lived experiences in ways that change dominant and, therefore, unchallenged views about them (Servaes & Malikhao 2014). In facilitating DST workshops with the SFL Advocates, I searched for evidence of epistemic (in)justice to enhance our (all stakeholders) understanding of their literacy experiences in ways that addressed their credibility status as ‘knowers’ (Fricker, 2007). Viewed through this lens, utilising DST provided a mechanism for understanding the impact of social interventions in a university setting that aimed to correct past injustices. The process involved online and face-to-face workshops with the participants during the Covid-19 Lockdown. The online format hampered data collection processes, and I resorted to face-to-face interactions for the workshops and interviews. These interactions were distinctly different from those I had experienced with participants in previous workshops, and they became a key focus in my analysis. Using narrative inquiry with critical realist and interpretive analysis techniques to interrogate the data, I discovered DST has both weaknesses and strengths as a C4SC communication tool. My findings revealed participants who, in the moment of leading their children and communities through the family literacy intervention, could claim to have redressed epistemic harms from the legacy of Apartheid education. However, by reflecting on this moment, the participants brought to light an epistemic harm that had been previously left unspoken: their sense of restored credibility as knowledge-bearers during the intervention was deeply shaken when the programme ended because they felt abandoned by the university. Therefore, the epistemic (in)justice lens unveiled hidden injustices that curtailed the participants’ ability to participate fully in the DST workshops. They described suffering the effects of pernicious and arbitrary acts of epistemic injustice at the hands of the University. Their participation in my workshops was erratic, and their stories were incomplete. As a result, I experienced difficulty analysing what I perceived as a lack of data. Moreover, despite my independent researcher status, my positionality as participant-observer was problematic as the participants may have perceived me as representative of the University and its institutional power. I responded to the problematic data by including a new theoretical framework in my analysis: the theory of everyday resistance (Vinthagen & Johansson, 2013). Combined with epistemic (in)justice theory and Vivienne’s ideas of using DST for everyday activism, I theorised how the participants negotiated their expressions of identity in epistemically unjust spaces. To put institutional epistemic injustice in perspective in the context of the University, I drew on Fricker’s three models of epistemic justice that enable fair and free conditions for marginalised workers to communicate for social change. , Thesis (MA) -- Faculty of Humanities, Journalism and Media Studies, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Viedge, Jane Margaret
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/432308 , vital:72860
- Description: This thesis sets out to establish in what ways digital storytelling (DST) revealed instances of epistemic (in)justices inherent in the family literacy intervention experiences of four Black, working-class parents employed at a South African University1. Additionally, it explores how DST might be used by the participants (self-labelled the Storytelling Family Literacy - SFL Advocates) to correct any harm done. The context for the research is based on the deep-rooted harms of Bantu education in which Black South Africans were denied equal access to resources such as literacy practices. I investigated these aims by using the theories of DST, Communication for Social Change (C4SC) and epistemic (in)justice. As a participatory media practice supporting communications in marginalised communities, DST’s broad purpose is to assist these communities in telling stories of their lived experiences in ways that change dominant and, therefore, unchallenged views about them (Servaes & Malikhao 2014). In facilitating DST workshops with the SFL Advocates, I searched for evidence of epistemic (in)justice to enhance our (all stakeholders) understanding of their literacy experiences in ways that addressed their credibility status as ‘knowers’ (Fricker, 2007). Viewed through this lens, utilising DST provided a mechanism for understanding the impact of social interventions in a university setting that aimed to correct past injustices. The process involved online and face-to-face workshops with the participants during the Covid-19 Lockdown. The online format hampered data collection processes, and I resorted to face-to-face interactions for the workshops and interviews. These interactions were distinctly different from those I had experienced with participants in previous workshops, and they became a key focus in my analysis. Using narrative inquiry with critical realist and interpretive analysis techniques to interrogate the data, I discovered DST has both weaknesses and strengths as a C4SC communication tool. My findings revealed participants who, in the moment of leading their children and communities through the family literacy intervention, could claim to have redressed epistemic harms from the legacy of Apartheid education. However, by reflecting on this moment, the participants brought to light an epistemic harm that had been previously left unspoken: their sense of restored credibility as knowledge-bearers during the intervention was deeply shaken when the programme ended because they felt abandoned by the university. Therefore, the epistemic (in)justice lens unveiled hidden injustices that curtailed the participants’ ability to participate fully in the DST workshops. They described suffering the effects of pernicious and arbitrary acts of epistemic injustice at the hands of the University. Their participation in my workshops was erratic, and their stories were incomplete. As a result, I experienced difficulty analysing what I perceived as a lack of data. Moreover, despite my independent researcher status, my positionality as participant-observer was problematic as the participants may have perceived me as representative of the University and its institutional power. I responded to the problematic data by including a new theoretical framework in my analysis: the theory of everyday resistance (Vinthagen & Johansson, 2013). Combined with epistemic (in)justice theory and Vivienne’s ideas of using DST for everyday activism, I theorised how the participants negotiated their expressions of identity in epistemically unjust spaces. To put institutional epistemic injustice in perspective in the context of the University, I drew on Fricker’s three models of epistemic justice that enable fair and free conditions for marginalised workers to communicate for social change. , Thesis (MA) -- Faculty of Humanities, Journalism and Media Studies, 2023
- Full Text:
- Date Issued: 2023-10-13
Kenyan comedy: transmogrifying stereotypes and fashioning a ‘Kenyanness’ of aesthetic escapism
- Authors: Lumasia, Patrick Chesi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432477 , vital:72874 , DOI 10.21504/10962/432477
- Description: Despite the proliferation of stereotypes in Kenyan comedy, little research exists to show the two intersect to shape a peculiar notion of ‘Kenyanness’. Indeed, Kenyan comedy, besides reproducing and playing on the quotidian and the historical, is heavily invested with ethnic and gender stereotypes that reflect the Kenyan milieu as it intersects with the global. This comedy is oftentimes seen by some critics as detrimental to Kenyan society because it supposedly shapes and reinforces ethnic and/or gender relations in the country. However, this study contends that Kenyan comedy is open to multiple interpretations and meaning contestations that are not necessarily clear to the comedians and audiences due to the asymmetry that abounds between the production and consumption ends of the comedy’s spectrum. The comedy is therefore ambivalent. This research seeks to demonstrate that Kenyan comedy—as a form of entertainment and critique of society—does not seek to fix and reify Kenyan identities. Instead, the comedy frees these identities from the presumed vice-hold, constricting world of stereotypes by disrupting the linearity of the stereotypes, thereby unsettling the hierarchical structure of hegemonic ideology embedded in them through postmodern humour: a form of humour amenable to postmodern sensibilities. To this end, the comedy offers Kenyans momentary escape into a comedic utopia, through which, they address pertinent issues affecting their nationhood, even as they endeavor to fashion a ‘Kenyanness’ of aesthetic escapism that is celebratory of the country’s rich socio-cultural diversity. The study employs Jörg Schweinitz’s (2011) stereotype theory and the postpositivist realist theory of identity in its study of stand-up, scripted episodic and topical comedy as transposed on to YouTube. Specifically, the thesis considers: the Churchill Show (2012 – 2022) that aired on NTV; 2012–2022; The Real Househelps of Kawangware (2014–2021) on KTN/NTV; Auntie Boss (2016–2021) on NTV; The Wicked Edition and The Trending Trend Talkers (2014–). , Thesis (PhD) -- Faculty of Humanities, Literary Studies in English, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Lumasia, Patrick Chesi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432477 , vital:72874 , DOI 10.21504/10962/432477
- Description: Despite the proliferation of stereotypes in Kenyan comedy, little research exists to show the two intersect to shape a peculiar notion of ‘Kenyanness’. Indeed, Kenyan comedy, besides reproducing and playing on the quotidian and the historical, is heavily invested with ethnic and gender stereotypes that reflect the Kenyan milieu as it intersects with the global. This comedy is oftentimes seen by some critics as detrimental to Kenyan society because it supposedly shapes and reinforces ethnic and/or gender relations in the country. However, this study contends that Kenyan comedy is open to multiple interpretations and meaning contestations that are not necessarily clear to the comedians and audiences due to the asymmetry that abounds between the production and consumption ends of the comedy’s spectrum. The comedy is therefore ambivalent. This research seeks to demonstrate that Kenyan comedy—as a form of entertainment and critique of society—does not seek to fix and reify Kenyan identities. Instead, the comedy frees these identities from the presumed vice-hold, constricting world of stereotypes by disrupting the linearity of the stereotypes, thereby unsettling the hierarchical structure of hegemonic ideology embedded in them through postmodern humour: a form of humour amenable to postmodern sensibilities. To this end, the comedy offers Kenyans momentary escape into a comedic utopia, through which, they address pertinent issues affecting their nationhood, even as they endeavor to fashion a ‘Kenyanness’ of aesthetic escapism that is celebratory of the country’s rich socio-cultural diversity. The study employs Jörg Schweinitz’s (2011) stereotype theory and the postpositivist realist theory of identity in its study of stand-up, scripted episodic and topical comedy as transposed on to YouTube. Specifically, the thesis considers: the Churchill Show (2012 – 2022) that aired on NTV; 2012–2022; The Real Househelps of Kawangware (2014–2021) on KTN/NTV; Auntie Boss (2016–2021) on NTV; The Wicked Edition and The Trending Trend Talkers (2014–). , Thesis (PhD) -- Faculty of Humanities, Literary Studies in English, 2023
- Full Text:
- Date Issued: 2023-10-13