English morphological awareness and reading comprehension in deaf and hearing grade 3 to 7 learners from Lesotho
- Authors: Tšehla, Puleng Magret
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/${Handle} , vital:73169
- Description: There is a noticeable literacy crisis observed in both Deaf and hearing learners from Lesotho. This study investigates the English Morphological Awareness and reading comprehension of 26 Deaf and 82 hearing learners enrolled in grades 3 to 7 in two schools in Lesotho. This study employs a correlational cross-sectional quantitative design. Each participant completed two literacy assessment tasks: a reading comprehension task and a Morphological Awareness task. The Morphological Awareness task encompassed five subtasks that assessed the learners’ inflectional, derivational, and compound awareness. The results of these assessments are analysed through appropriate statistical analyses. In addition, errors made by the Deaf and hearing learners on the literacy assessments are compared and analysed. This analysis determines the types of errors made by each group and identifies the factors that influence these errors. The performance of both groups in terms of task scores, in general, was low. Deaf learners and hearing learners’ performance on the tasks was similar. This outcome contradicts most previous studies, which indicate that Deaf learners typically exhibit lower levels of Morphological Awareness development and reading comprehension compared to their hearing counterparts. The results of this study also suggest that there is a statistically significant relationship between Morphological Awareness and reading comprehension in both groups. Finally, Deaf and hearing learners made similar errors on the tasks. There was some evidence of influence from both the Deaf and hearing learners’ first languages (Sesotho and Lesotho Sign Language, respectively). The study demonstrates the need for more explicit morphological instruction to improve both Deaf and hearing learners’ literacy. , Thesis (MA) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Tšehla, Puleng Magret
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/${Handle} , vital:73169
- Description: There is a noticeable literacy crisis observed in both Deaf and hearing learners from Lesotho. This study investigates the English Morphological Awareness and reading comprehension of 26 Deaf and 82 hearing learners enrolled in grades 3 to 7 in two schools in Lesotho. This study employs a correlational cross-sectional quantitative design. Each participant completed two literacy assessment tasks: a reading comprehension task and a Morphological Awareness task. The Morphological Awareness task encompassed five subtasks that assessed the learners’ inflectional, derivational, and compound awareness. The results of these assessments are analysed through appropriate statistical analyses. In addition, errors made by the Deaf and hearing learners on the literacy assessments are compared and analysed. This analysis determines the types of errors made by each group and identifies the factors that influence these errors. The performance of both groups in terms of task scores, in general, was low. Deaf learners and hearing learners’ performance on the tasks was similar. This outcome contradicts most previous studies, which indicate that Deaf learners typically exhibit lower levels of Morphological Awareness development and reading comprehension compared to their hearing counterparts. The results of this study also suggest that there is a statistically significant relationship between Morphological Awareness and reading comprehension in both groups. Finally, Deaf and hearing learners made similar errors on the tasks. There was some evidence of influence from both the Deaf and hearing learners’ first languages (Sesotho and Lesotho Sign Language, respectively). The study demonstrates the need for more explicit morphological instruction to improve both Deaf and hearing learners’ literacy. , Thesis (MA) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2024
- Full Text:
- Date Issued: 2024-04-04
Functional significance of mixed-species groups for zebra (Equus quagga) in savanna habitats
- Corry-Roberts, Carys Alexandra
- Authors: Corry-Roberts, Carys Alexandra
- Date: 2024-04-04
- Subjects: Herding behavior in animals , Zebras Food , Foraging , Zebras Behavior , Zebras Conservation , Herbivores Habitat
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434925 , vital:73116
- Description: Globally, herbivore populations are facing decline, which threatens their crucial role within the ecosystems they inhabit. Herbivores are essential to ecosystem structure and function because they act as prey for higher trophic levels, cycle soil nutrients, and alter vegetation structure. Understanding the drivers that shape herbivore habitat use and selection are therefore critical for making informed conservation and management decisions. Like all prey species, herbivores must balance a trade-off between acquiring resources and avoiding predation which is influenced by a number of species-specific intrinsic traits and various ecological drivers. Herbivores can also track risk over space and time, and certain habitat structures and landscape features can influence risk perception; this is termed the landscape of fear. To mitigate the risk-reward trade-off, herbivores employ a suite of behavioural responses. Group formation is likely the most well-documented of these responses. However, grouping results in the information-competition trade-off, wherein group members may obtain valuable information regarding the location of resources and/or the risk of predation, but may suffer from increased competition, especially among larger group sizes. Mixed-species groups—an assemblage of two or more species in close spatial association—have the potential to mitigate some of the competitive costs of larger conspecific groups and enhance the anti-predator and/or foraging benefits of grouping. African savannas provide a particularly useful natural laboratory to study mixed-species groups, due to the high diversity of prey species and habitat heterogeneity present. Previous studies have investigated the mixed-species effect within these systems, but have yet to quantify some of the identity-dependent costs and benefits associated with mixed-species herding. Thus, the overall aim of my study was to quantify the functional significance of mixed-species groups for zebra (Equus quagga) herding with two of their most common herding partners, impala (Aepyceros melampus) and wildebeest (Connochaetes taurinus). My study was conducted at multiple spatial scales in the southern portion of the Kruger National Park, South Africa between 2021 and 2022. I found that mixed-species herding altered zebra landscape use, resulting in a quantifiable intensification of habitat use compared to when they herd with conspecifics. I did not observe significant habitat expansion for zebra in mixed-species herds compared to single-species herds, likely because the anti-predator benefits of mixed-species herding convey enhanced foraging opportunities in already-safe habitats. Zebra foraging with impala achieved greater foraging success and experienced lower levels of competition, compared to zebra foraging with wildebeest. However, compared to foraging with conspecifics, the levelled landscape of fear zebra experienced when foraging with wildebeest resulted in increased foraging success across the landscape. My findings highlight the context-dependency of the costs and benefits associated with different herding partners for zebra, and suggest that in mixed-species herds with wildebeest, zebra experience increased potential fitness benefits compared to herding with impala or conspecifics. Overall, the findings of my study suggest that mixed-species herding is an important tool in the suite of anti-predator behaviours employed by prey species, and one with significant implications for survivorship, habitat use, and ultimately, community level interactions. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Corry-Roberts, Carys Alexandra
- Date: 2024-04-04
- Subjects: Herding behavior in animals , Zebras Food , Foraging , Zebras Behavior , Zebras Conservation , Herbivores Habitat
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434925 , vital:73116
- Description: Globally, herbivore populations are facing decline, which threatens their crucial role within the ecosystems they inhabit. Herbivores are essential to ecosystem structure and function because they act as prey for higher trophic levels, cycle soil nutrients, and alter vegetation structure. Understanding the drivers that shape herbivore habitat use and selection are therefore critical for making informed conservation and management decisions. Like all prey species, herbivores must balance a trade-off between acquiring resources and avoiding predation which is influenced by a number of species-specific intrinsic traits and various ecological drivers. Herbivores can also track risk over space and time, and certain habitat structures and landscape features can influence risk perception; this is termed the landscape of fear. To mitigate the risk-reward trade-off, herbivores employ a suite of behavioural responses. Group formation is likely the most well-documented of these responses. However, grouping results in the information-competition trade-off, wherein group members may obtain valuable information regarding the location of resources and/or the risk of predation, but may suffer from increased competition, especially among larger group sizes. Mixed-species groups—an assemblage of two or more species in close spatial association—have the potential to mitigate some of the competitive costs of larger conspecific groups and enhance the anti-predator and/or foraging benefits of grouping. African savannas provide a particularly useful natural laboratory to study mixed-species groups, due to the high diversity of prey species and habitat heterogeneity present. Previous studies have investigated the mixed-species effect within these systems, but have yet to quantify some of the identity-dependent costs and benefits associated with mixed-species herding. Thus, the overall aim of my study was to quantify the functional significance of mixed-species groups for zebra (Equus quagga) herding with two of their most common herding partners, impala (Aepyceros melampus) and wildebeest (Connochaetes taurinus). My study was conducted at multiple spatial scales in the southern portion of the Kruger National Park, South Africa between 2021 and 2022. I found that mixed-species herding altered zebra landscape use, resulting in a quantifiable intensification of habitat use compared to when they herd with conspecifics. I did not observe significant habitat expansion for zebra in mixed-species herds compared to single-species herds, likely because the anti-predator benefits of mixed-species herding convey enhanced foraging opportunities in already-safe habitats. Zebra foraging with impala achieved greater foraging success and experienced lower levels of competition, compared to zebra foraging with wildebeest. However, compared to foraging with conspecifics, the levelled landscape of fear zebra experienced when foraging with wildebeest resulted in increased foraging success across the landscape. My findings highlight the context-dependency of the costs and benefits associated with different herding partners for zebra, and suggest that in mixed-species herds with wildebeest, zebra experience increased potential fitness benefits compared to herding with impala or conspecifics. Overall, the findings of my study suggest that mixed-species herding is an important tool in the suite of anti-predator behaviours employed by prey species, and one with significant implications for survivorship, habitat use, and ultimately, community level interactions. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
High-altitude temporary systems and macroinvertebrate composition in La Nina cycle, Maloti-Drakensberg
- Authors: Moyo, Sibusisiwe
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434963 , vital:73119
- Description: The Maloti-Drakensberg Mountain is an important water catchment area for South Africa and Lesotho. It is rich in biodiversity in terms of endemic flora and fauna and has a high density of temporary wetlands in the form of Afromontane tarns and rock pools. There is, however, limited information on the distribution of macroinvertebrates in these ecosystems and environmental factors that drives their composition. To that end, this study investigated macroinvertebrate diversity and the effect of environmental factors on community assemblage in the Maloti-Drakensberg Mountain temporary wetlands, specifically tarns and rock pools. The main aims were to describe the abundance, diversity, and distribution of macroinvertebrates in temporary wetlands in the Maloti-Drakensberg Mountain. Furthermore, it aimed to investigate the effect of environmental variables on habitat structuring, spatial variations, and macroinvertebrate community composition in tarns and rockpools in the Maloti-Drakensberg Mountain. Seventy temporary wetlands (29 tarns and 41 rock pools) were surveyed over a once-off sampling (3 March – 7 April 2022). The wetlands were from 3 provinces including Eastern Cape, Free State, and KwaZulu-Natal. 15278 individual macroinvertebrates from 13 orders, 35 families, and 46 genera were collected and identified. Species accumulation curves incorporating both tarns and rock pools showed that observed results were significantly lower than Chao 1 and Chao 2 estimates meaning that the sampled sites were not enough to provide a comprehensive picture of the biodiversity in the region. This was also observed for rock pools when the temporary wetlands were analysed separately, however, the Chao 1 and Chao 2 values for tarns were almost equal to the observed values implying that sampled sites were enough to give a detailed picture of macroinvertebrate composition in tarns. Tarns and rock pools were significantly different in terms of species richness and Shannon-Wiener diversity index but showed no significant differences for relative abundance and Pielou’s evenness. Of the 35 families identified, 19 were considered core taxa with Dytiscidae and Corixidae being the most dominant. Additionally, there was moderate Nestedness metric based on Overlap and Decreasing Fill (NODF) value of 33.05369, with 32 out of 35 families being idiosyncratic. Predators were the dominant feeding group with omnivores being the least common. Non-Metric multi-Dimensional Scaling (NMDS) and PERMANOVA results showed that tarns and rock pools supported distinctly different macroinvertebrate communities per wetland type and location respectively. Physicochemically, tarns and rock pools were significantly different in terms of water temperature, depth, area, and chlorophyll-a concentration with tarns exhibiting higher values. Temporary wetlands in the sampled localities differed in terms of pH, EC, DO, water temperature, altitude, and phosphate. Principal Component Analysis showed that tarns were positively associated with area and depth whereas rock pools with phosphate. Akaike’s Information Criterion (AICc) selection showed that area, pH, and water temperature were significantly influencing community assemblage in temporary wetlands. Furthermore, area significantly influenced all four measured biodiversity indices: relative abundance, species richness, Pielou’s evenness and Shannon-Wiener Index, with water temperature also influencing relative abundance and altitude, species richness. Overall, the species composition showed that the sites were sampled later in the hydroperiod as evidenced by the dominance of active dispersers. The extended distribution of Prosthetops gladiator in the Eastern Cape highlights the need for extensive surveys to provide valuable insight into the distribution patterns of macroinvertebrates in the region. Furthermore, the interplay between physicochemical variables and biodiversity indices emphasized area, water temperature and pH as significant factors. However, their limited explanatory power suggests that obscure factors also influence the diversity cementing the need for further exploration of these enigmatic systems. Taxonomic challenges, especially regarding large branchiopods, hindered precise species distribution and conservation status determination. This study is the first to provide a comprehensive list of macroinvertebrates from temporary wetlands in the Maloti-Drakensberg Mountain. These results establish a valuable baseline for future biological monitoring studies, particularly in assessing species composition and responses to anthropogenic activities. It is a timeous study considering the sensitivity of these systems to climate change as they act as sentinel sites hence the need for foundational data on which to make future projections. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Moyo, Sibusisiwe
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434963 , vital:73119
- Description: The Maloti-Drakensberg Mountain is an important water catchment area for South Africa and Lesotho. It is rich in biodiversity in terms of endemic flora and fauna and has a high density of temporary wetlands in the form of Afromontane tarns and rock pools. There is, however, limited information on the distribution of macroinvertebrates in these ecosystems and environmental factors that drives their composition. To that end, this study investigated macroinvertebrate diversity and the effect of environmental factors on community assemblage in the Maloti-Drakensberg Mountain temporary wetlands, specifically tarns and rock pools. The main aims were to describe the abundance, diversity, and distribution of macroinvertebrates in temporary wetlands in the Maloti-Drakensberg Mountain. Furthermore, it aimed to investigate the effect of environmental variables on habitat structuring, spatial variations, and macroinvertebrate community composition in tarns and rockpools in the Maloti-Drakensberg Mountain. Seventy temporary wetlands (29 tarns and 41 rock pools) were surveyed over a once-off sampling (3 March – 7 April 2022). The wetlands were from 3 provinces including Eastern Cape, Free State, and KwaZulu-Natal. 15278 individual macroinvertebrates from 13 orders, 35 families, and 46 genera were collected and identified. Species accumulation curves incorporating both tarns and rock pools showed that observed results were significantly lower than Chao 1 and Chao 2 estimates meaning that the sampled sites were not enough to provide a comprehensive picture of the biodiversity in the region. This was also observed for rock pools when the temporary wetlands were analysed separately, however, the Chao 1 and Chao 2 values for tarns were almost equal to the observed values implying that sampled sites were enough to give a detailed picture of macroinvertebrate composition in tarns. Tarns and rock pools were significantly different in terms of species richness and Shannon-Wiener diversity index but showed no significant differences for relative abundance and Pielou’s evenness. Of the 35 families identified, 19 were considered core taxa with Dytiscidae and Corixidae being the most dominant. Additionally, there was moderate Nestedness metric based on Overlap and Decreasing Fill (NODF) value of 33.05369, with 32 out of 35 families being idiosyncratic. Predators were the dominant feeding group with omnivores being the least common. Non-Metric multi-Dimensional Scaling (NMDS) and PERMANOVA results showed that tarns and rock pools supported distinctly different macroinvertebrate communities per wetland type and location respectively. Physicochemically, tarns and rock pools were significantly different in terms of water temperature, depth, area, and chlorophyll-a concentration with tarns exhibiting higher values. Temporary wetlands in the sampled localities differed in terms of pH, EC, DO, water temperature, altitude, and phosphate. Principal Component Analysis showed that tarns were positively associated with area and depth whereas rock pools with phosphate. Akaike’s Information Criterion (AICc) selection showed that area, pH, and water temperature were significantly influencing community assemblage in temporary wetlands. Furthermore, area significantly influenced all four measured biodiversity indices: relative abundance, species richness, Pielou’s evenness and Shannon-Wiener Index, with water temperature also influencing relative abundance and altitude, species richness. Overall, the species composition showed that the sites were sampled later in the hydroperiod as evidenced by the dominance of active dispersers. The extended distribution of Prosthetops gladiator in the Eastern Cape highlights the need for extensive surveys to provide valuable insight into the distribution patterns of macroinvertebrates in the region. Furthermore, the interplay between physicochemical variables and biodiversity indices emphasized area, water temperature and pH as significant factors. However, their limited explanatory power suggests that obscure factors also influence the diversity cementing the need for further exploration of these enigmatic systems. Taxonomic challenges, especially regarding large branchiopods, hindered precise species distribution and conservation status determination. This study is the first to provide a comprehensive list of macroinvertebrates from temporary wetlands in the Maloti-Drakensberg Mountain. These results establish a valuable baseline for future biological monitoring studies, particularly in assessing species composition and responses to anthropogenic activities. It is a timeous study considering the sensitivity of these systems to climate change as they act as sentinel sites hence the need for foundational data on which to make future projections. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
Home is in the wandering
- Authors: Purdon, Bradley Michael
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435547 , vital:73167
- Description: Submitted in partial fulfilment of the requirements for the degree of Master of Arts in Creative Writing , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Purdon, Bradley Michael
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435547 , vital:73167
- Description: Submitted in partial fulfilment of the requirements for the degree of Master of Arts in Creative Writing , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-04-04
Identifying the factors that influence parents and caregivers to commit child maltreatment: systematic review
- Authors: Dipholo, Mamdlalose Emily
- Date: 2024-04-04
- Subjects: Abusive parents , Child abuse Psychological aspects , Child caregivers , Systematic review , Holistic paradigm
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435421 , vital:73156
- Description: Child maltreatment, encompassing various forms of abuse and neglect, poses a significant global public health concern. This study provides a comprehensive examination of the multifaceted dimensions of child maltreatment, including physical, emotional, and sexual abuse, as well as neglect. The impact of maltreatment on the developing child is profound, resulting in a range of adverse physical and mental health outcomes, developmental delays, behavioural challenges, and social difficulties. The aim of this study was to comprehensively review and synthesise peer-reviewed research on the factors influencing parents and caregivers in committing child maltreatment. This systematic review identified the multifaceted factors influencing parents and caregivers to engage in child maltreatment. Using a social ecological framework, ten key themes emerged, namely poverty and lack of access to services, intergenerational transmission of abuse, childhood trauma, substance abuse, domestic violence, neighbourhood violence, cultural practices, social factors, children’s individual factors, and caregivers' mental health concerns. Personal history, caregiver’s mental health, substance abuse, poor awareness of self-protection, and gender emerged as significant individual-level contributors. Non biological caregivers and domestic violence were identified as relationship-level factors. At the community level, poverty, lack of access to services, unemployment, and neighbourhood violence were found to impact child maltreatment. Cultural values and the intergenerational transmission of abuse were reported as influential societal-level factors. The study underscores the complex interplay of personal, environmental, and cultural influences in child maltreatment, highlighting the need for comprehensive strategies to address this critical issue. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Dipholo, Mamdlalose Emily
- Date: 2024-04-04
- Subjects: Abusive parents , Child abuse Psychological aspects , Child caregivers , Systematic review , Holistic paradigm
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435421 , vital:73156
- Description: Child maltreatment, encompassing various forms of abuse and neglect, poses a significant global public health concern. This study provides a comprehensive examination of the multifaceted dimensions of child maltreatment, including physical, emotional, and sexual abuse, as well as neglect. The impact of maltreatment on the developing child is profound, resulting in a range of adverse physical and mental health outcomes, developmental delays, behavioural challenges, and social difficulties. The aim of this study was to comprehensively review and synthesise peer-reviewed research on the factors influencing parents and caregivers in committing child maltreatment. This systematic review identified the multifaceted factors influencing parents and caregivers to engage in child maltreatment. Using a social ecological framework, ten key themes emerged, namely poverty and lack of access to services, intergenerational transmission of abuse, childhood trauma, substance abuse, domestic violence, neighbourhood violence, cultural practices, social factors, children’s individual factors, and caregivers' mental health concerns. Personal history, caregiver’s mental health, substance abuse, poor awareness of self-protection, and gender emerged as significant individual-level contributors. Non biological caregivers and domestic violence were identified as relationship-level factors. At the community level, poverty, lack of access to services, unemployment, and neighbourhood violence were found to impact child maltreatment. Cultural values and the intergenerational transmission of abuse were reported as influential societal-level factors. The study underscores the complex interplay of personal, environmental, and cultural influences in child maltreatment, highlighting the need for comprehensive strategies to address this critical issue. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-04-04
Insights: elucidation of squalene monooxygenase inhibitors for lowering cholesterol in cardiovascular diseases
- Authors: Leoma, Mofeli Benedict
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434861 , vital:73111
- Description: Statins have been used to lower high cholesterol levels in the past few decades. However, several studies have shown that some people taking statins experience side effects over time, especially elderly patients, women of childbirth possibility, and children. Several studies have shown that the majority of people with underlying cardiovascular complications caused by high cholesterol are at a greater risk of fatality due to COVID-19, regardless of age and sex. The literature suggests that antimycotic squalene monooxygenase inhibitors, terbinafine and its derivatives, and anticholesterolemic squalene monooxygenase (SM) inhibitors could be another option and a safer remedy for lowering cholesterol in mammals. Molecular docking calculations, molecular dynamics (MD) simulations, molecular mechanics generalized born surface area (MM-GBSA) calculations, quantum mechanics/molecular mechanics calculations (QM/MM), and density functional theory (DFT) calculations were used in this study. An early stage in drug discovery, in which small molecular hits from high- throughput screening (HTS) are evaluated and undergo limited optimization to identify promising lead compounds, is referred to as lead generation. To address the first step of lead generation, the number of compounds to be tested was narrowed down, and the hit compounds that could be taken for further tests were obtained. Thus, the molecular docking technique was taken advantage of, which assisted us in identifying the antimycotic ligand SDZ 18, which had a good binding affinity of about -8,4 kcal mol−1. Another widely employed strategy, the molecular mechanics-generalized born surface area (MM-GBSA), was used to investigate the binding free energies of the protein-ligand complexes to validate the binding affinities obtained from molecular docking. Despite the excellent docking results, it must be emphasized that the stability of the ligand in the binding pocket must be investigated. To address this, the protein-ligand complexes were then taken through molecular dynamics for 100 ns simulations calculations which showed that the inhibitors stayed in the binding pocket with the RMSD values below 3.5 Å for most systems. This provided insight into a realistic model because the docked complexes were placed in conditions closer to the physiological environment at 300 K and 1.01325 bar, and in an explicitly solvated dynamic environment. Density functional theory (DFT) at the B3LPY level of theory using the standard 6-31G(d,p) basis set was used to assess the reactivity and other properties of the SM inhibitors. ONIOM calculations were performed to explain what was happening at the microscopic level by calculating the total energy of the complex. The aim of this project was to efficiently uncover the non-physical aspects of SM inhibitors with the help of computational techniques to identify new drugs that can lower high cholesterol levels. From a theoretical perspective, the results obtained from docking indicated that the antimycotic ligands SDZ SBA 586 18 and TNSA 84 (trisnor-squalene alcohol ) have good binding affinities, and the MM-GBSA method provided free energy calculations. MD results indicated that the stability of the ligand in the binding pocket was achieved during the 100 ns simulations. The HOMO-LUMO energy gaps obtained from DFT calculations provided information on the reactivity of the ligands. Other insights into the protein-ligand complexes were obtained from a hybrid ONIOM QM/MM study. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Leoma, Mofeli Benedict
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434861 , vital:73111
- Description: Statins have been used to lower high cholesterol levels in the past few decades. However, several studies have shown that some people taking statins experience side effects over time, especially elderly patients, women of childbirth possibility, and children. Several studies have shown that the majority of people with underlying cardiovascular complications caused by high cholesterol are at a greater risk of fatality due to COVID-19, regardless of age and sex. The literature suggests that antimycotic squalene monooxygenase inhibitors, terbinafine and its derivatives, and anticholesterolemic squalene monooxygenase (SM) inhibitors could be another option and a safer remedy for lowering cholesterol in mammals. Molecular docking calculations, molecular dynamics (MD) simulations, molecular mechanics generalized born surface area (MM-GBSA) calculations, quantum mechanics/molecular mechanics calculations (QM/MM), and density functional theory (DFT) calculations were used in this study. An early stage in drug discovery, in which small molecular hits from high- throughput screening (HTS) are evaluated and undergo limited optimization to identify promising lead compounds, is referred to as lead generation. To address the first step of lead generation, the number of compounds to be tested was narrowed down, and the hit compounds that could be taken for further tests were obtained. Thus, the molecular docking technique was taken advantage of, which assisted us in identifying the antimycotic ligand SDZ 18, which had a good binding affinity of about -8,4 kcal mol−1. Another widely employed strategy, the molecular mechanics-generalized born surface area (MM-GBSA), was used to investigate the binding free energies of the protein-ligand complexes to validate the binding affinities obtained from molecular docking. Despite the excellent docking results, it must be emphasized that the stability of the ligand in the binding pocket must be investigated. To address this, the protein-ligand complexes were then taken through molecular dynamics for 100 ns simulations calculations which showed that the inhibitors stayed in the binding pocket with the RMSD values below 3.5 Å for most systems. This provided insight into a realistic model because the docked complexes were placed in conditions closer to the physiological environment at 300 K and 1.01325 bar, and in an explicitly solvated dynamic environment. Density functional theory (DFT) at the B3LPY level of theory using the standard 6-31G(d,p) basis set was used to assess the reactivity and other properties of the SM inhibitors. ONIOM calculations were performed to explain what was happening at the microscopic level by calculating the total energy of the complex. The aim of this project was to efficiently uncover the non-physical aspects of SM inhibitors with the help of computational techniques to identify new drugs that can lower high cholesterol levels. From a theoretical perspective, the results obtained from docking indicated that the antimycotic ligands SDZ SBA 586 18 and TNSA 84 (trisnor-squalene alcohol ) have good binding affinities, and the MM-GBSA method provided free energy calculations. MD results indicated that the stability of the ligand in the binding pocket was achieved during the 100 ns simulations. The HOMO-LUMO energy gaps obtained from DFT calculations provided information on the reactivity of the ligands. Other insights into the protein-ligand complexes were obtained from a hybrid ONIOM QM/MM study. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-04-04
Interlingual and intercultural communication discordances as impediments to the provision of quality public healthcare services: cases of Cecilia Makiwane Hospital, Nkqubela Chest Hospital and Frere Hospital
- Authors: Hlitane, Nkosekaya
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435501 , vital:73163
- Description: This study seeks to explore interlingual and intercultural discordances between clinicians and patients during treatment processes in selected public hospitals in the Eastern Cape. The two languages under investigation are English and isiXhosa. Intercultural communication refers to a phenomenon in which people who speak different native languages are engaged in a conversation (Gudykunst 1993). , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Hlitane, Nkosekaya
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435501 , vital:73163
- Description: This study seeks to explore interlingual and intercultural discordances between clinicians and patients during treatment processes in selected public hospitals in the Eastern Cape. The two languages under investigation are English and isiXhosa. Intercultural communication refers to a phenomenon in which people who speak different native languages are engaged in a conversation (Gudykunst 1993). , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-04-04
Investigating changes in pineapple (Aananas comosus) cultivation in the Eastern Cape, South Africa, from 1984 to 2020
- Authors: Marriner, Paul Joseph
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435354 , vital:73150
- Description: Land use and land cover change (LULCC) resulting from agricultural activities have significantly impacted landscape transformation and fragmentation. The Albany Thicket Biome in the Eastern Cape Province stands out for its exceptional vegetation diversity and remarkable rates of species endemism. However, the relationship between agricultural activities and the Albany Thicket Biome has not received sufficient attention in the literature, creating a significant gap in understanding the extent of landscape transformation and the vegetation's recovery rate. This study aims to address this gap by utilising remote sensing technologies to investigate the LULCC specifically caused by pineapple cultivation in the Lower Albany area between 1984 and 2020. Analysis, using remotely sensed imagery and spatial analytical tools, provide accurate identification of pineapple fields and enable monitoring of their effects on LULCC dynamics across a wide spatial and temporal scale. Complementary field assessments examined the impacts of pineapple cultivation on land use and cover. Twelve image classifiers were tested to identify the most appropriate technique for mapping pineapple fields, and the Supervised Pixel-based Support Vector Machine (SVM) image classifier was found to be the most suitable. Utilising Landsat 4, 5, 7, and 8 satellite imagery, 27 land cover maps were created, spanning the period from 1984 to 2020. Additionally, field verification was conducted at 59 randomly generated sites to validate the findings. Spatial analysis of the data revealed that the pineapple industry in the study area has expanded by 733 hectares since 1984. Significant land use changes were observed, including converting land to wildlife ranches, grazing areas, and alternative agricultural practices. The land cover analysis identified the emergence of pioneer species in former pineapple fields, suggesting the potential for Albany Thicket regrowth if appropriately managed. This research contributes to a better understanding of the impacts of pineapple cultivation on the Albany Thicket Biome and provides valuable insights for land use planning and monitoring efforts. A comprehensive assessment of LULCC dynamics can be achieved by utilising remote sensing techniques, informing sustainable land management practices in the study area and beyond. , Thesis (MSc) -- Faculty of Science, Geography, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Marriner, Paul Joseph
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435354 , vital:73150
- Description: Land use and land cover change (LULCC) resulting from agricultural activities have significantly impacted landscape transformation and fragmentation. The Albany Thicket Biome in the Eastern Cape Province stands out for its exceptional vegetation diversity and remarkable rates of species endemism. However, the relationship between agricultural activities and the Albany Thicket Biome has not received sufficient attention in the literature, creating a significant gap in understanding the extent of landscape transformation and the vegetation's recovery rate. This study aims to address this gap by utilising remote sensing technologies to investigate the LULCC specifically caused by pineapple cultivation in the Lower Albany area between 1984 and 2020. Analysis, using remotely sensed imagery and spatial analytical tools, provide accurate identification of pineapple fields and enable monitoring of their effects on LULCC dynamics across a wide spatial and temporal scale. Complementary field assessments examined the impacts of pineapple cultivation on land use and cover. Twelve image classifiers were tested to identify the most appropriate technique for mapping pineapple fields, and the Supervised Pixel-based Support Vector Machine (SVM) image classifier was found to be the most suitable. Utilising Landsat 4, 5, 7, and 8 satellite imagery, 27 land cover maps were created, spanning the period from 1984 to 2020. Additionally, field verification was conducted at 59 randomly generated sites to validate the findings. Spatial analysis of the data revealed that the pineapple industry in the study area has expanded by 733 hectares since 1984. Significant land use changes were observed, including converting land to wildlife ranches, grazing areas, and alternative agricultural practices. The land cover analysis identified the emergence of pioneer species in former pineapple fields, suggesting the potential for Albany Thicket regrowth if appropriately managed. This research contributes to a better understanding of the impacts of pineapple cultivation on the Albany Thicket Biome and provides valuable insights for land use planning and monitoring efforts. A comprehensive assessment of LULCC dynamics can be achieved by utilising remote sensing techniques, informing sustainable land management practices in the study area and beyond. , Thesis (MSc) -- Faculty of Science, Geography, 2024
- Full Text:
- Date Issued: 2024-04-04
Investigating playing-related musculoskeletal disorders in South African instrumental musicians
- Authors: Green, Erryn Mae
- Date: 2024-04-04
- Subjects: Musculoskeletal disorder , Musculoskeletal system Diseases , Musicians Wounds and injuries , Musicians Health and hygiene , Human engineering South Africa , Musicians Health risk assessment , Biomechanics , Musical instruments , Music genre
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435310 , vital:73146
- Description: This study, one of the first studies in SA to investigate PRMD in a wideranging sample of instrumental musicians using a validated self-report tool, shows that PRMDs are highly prevalent among a range of SA musicians and have a considerably negative effect on musicians’ performance ability and quality of life. However, making inferences about most affected genre or instrumental group was challenging due to the small sample sizes in some categories. The results from this study confirm that the nature of PRMD development is indeed multi-factorial, with factors numerous individual and playing-related factors playing a role in the development of PRMDs in SA musicians. Better support and education on health promotion for musicians, including awareness of and prevention strategies for PRMDs in the SA context are needed which may reduce the prevalence of PRMDs. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Green, Erryn Mae
- Date: 2024-04-04
- Subjects: Musculoskeletal disorder , Musculoskeletal system Diseases , Musicians Wounds and injuries , Musicians Health and hygiene , Human engineering South Africa , Musicians Health risk assessment , Biomechanics , Musical instruments , Music genre
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435310 , vital:73146
- Description: This study, one of the first studies in SA to investigate PRMD in a wideranging sample of instrumental musicians using a validated self-report tool, shows that PRMDs are highly prevalent among a range of SA musicians and have a considerably negative effect on musicians’ performance ability and quality of life. However, making inferences about most affected genre or instrumental group was challenging due to the small sample sizes in some categories. The results from this study confirm that the nature of PRMD development is indeed multi-factorial, with factors numerous individual and playing-related factors playing a role in the development of PRMDs in SA musicians. Better support and education on health promotion for musicians, including awareness of and prevention strategies for PRMDs in the SA context are needed which may reduce the prevalence of PRMDs. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2024
- Full Text:
- Date Issued: 2024-04-04
Investigating unimodal isolated signer-independent sign language recognition
- Authors: Marais, Marc Jason
- Date: 2024-04-04
- Subjects: Convolutional neural network , Sign language recognition , Human activity recognition , Pattern recognition systems , Neural networks (Computer science)
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435343 , vital:73149
- Description: Sign language serves as the mode of communication for the Deaf and Hard of Hearing community, embodying a rich linguistic and cultural heritage. Recent Sign Language Recognition (SLR) system developments aim to facilitate seamless communication between the Deaf community and the broader society. However, most existing systems are limited by signer-dependent models, hindering their adaptability to diverse signing styles and signers, thus impeding their practical implementation in real-world scenarios. This research explores various unimodal approaches, both pose-based and vision-based, for isolated signer-independent SLR using RGB video input on the LSA64 and AUTSL datasets. The unimodal RGB-only input strategy provides a realistic SLR setting where alternative data sources are either unavailable or necessitate specialised equipment. Through systematic testing scenarios, isolated signer-independent SLR experiments are conducted on both datasets, primarily focusing on AUTSL – a signer-independent dataset. The vision-based R(2+1)D-18 model emerged as the top performer, achieving 90.64% accuracy on the unseen AUTSL dataset test split, closely followed by the pose-based Spatio- Temporal Graph Convolutional Network (ST-GCN) model with an accuracy of 89.95%. Furthermore, these models achieved comparable accuracies at a significantly lower computational demand. Notably, the pose-based approach demonstrates robust generalisation to substantial background and signer variation. Moreover, the pose-based approach demands significantly less computational power and training time than vision-based approaches. The proposed unimodal pose-based and vision-based systems were concluded to both be effective at classifying sign classes in the LSA64 and AUTSL datasets. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Marais, Marc Jason
- Date: 2024-04-04
- Subjects: Convolutional neural network , Sign language recognition , Human activity recognition , Pattern recognition systems , Neural networks (Computer science)
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435343 , vital:73149
- Description: Sign language serves as the mode of communication for the Deaf and Hard of Hearing community, embodying a rich linguistic and cultural heritage. Recent Sign Language Recognition (SLR) system developments aim to facilitate seamless communication between the Deaf community and the broader society. However, most existing systems are limited by signer-dependent models, hindering their adaptability to diverse signing styles and signers, thus impeding their practical implementation in real-world scenarios. This research explores various unimodal approaches, both pose-based and vision-based, for isolated signer-independent SLR using RGB video input on the LSA64 and AUTSL datasets. The unimodal RGB-only input strategy provides a realistic SLR setting where alternative data sources are either unavailable or necessitate specialised equipment. Through systematic testing scenarios, isolated signer-independent SLR experiments are conducted on both datasets, primarily focusing on AUTSL – a signer-independent dataset. The vision-based R(2+1)D-18 model emerged as the top performer, achieving 90.64% accuracy on the unseen AUTSL dataset test split, closely followed by the pose-based Spatio- Temporal Graph Convolutional Network (ST-GCN) model with an accuracy of 89.95%. Furthermore, these models achieved comparable accuracies at a significantly lower computational demand. Notably, the pose-based approach demonstrates robust generalisation to substantial background and signer variation. Moreover, the pose-based approach demands significantly less computational power and training time than vision-based approaches. The proposed unimodal pose-based and vision-based systems were concluded to both be effective at classifying sign classes in the LSA64 and AUTSL datasets. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-04-04
It's all in your head
- Namukuta, Sonia Charity Sajjabi
- Authors: Namukuta, Sonia Charity Sajjabi
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435536 , vital:73166
- Description: My thesis is a collection of short stories that delve into the multifaceted nature of death, with a specific emphasis on murder, violence, death and their profound aftermath, including themes of loss, grief, and trauma. These stories offer diverse perspectives, narrated by perpetrators, voiceless victims, and those left to pick up the shattered pieces. Additionally, some stories are seen through the eyes of those tasked with handling the bodies. Often set in unnamed locations, they delve into imaginary and fantastical worlds, while remaining grounded in recognisable situations and spaces. I draw inspiration from popular and genre fiction such as horror, crime fiction and true crime stories, but approach my writing from a psychological lens, employing stylistic experimentation to challenge readers' expectations. The power of silence is a recurring motif. Rather than focusing on unearthing facts or revealing the "truth" like crime fiction often does, my narratives delve into what isn't or at times cannot be told — the unsayable. Some of my stories explore silence inherent in violence, grief, and the inability to articulate one's experience in the face of a violent act or a life prematurely ended. Others delve into the silence of untold stories and the dark secrets of the perpetrators. By exploring these contrasting perspectives, I aim to offer a nuanced exploration of death and its aftermath. The writing styles of Stephen Graham Jones, Lydia Davis, and Kuzhali Manickavel influence my work. Lydia Davis, known for her mastery of very short, flash fiction, ranging from single sentences to a paragraph or two, inspires me with her precise observations of the human condition. Her minimalist prose, carefully selecting and arranging words and sentences, encapsulates the power of less-is-more storytelling. Manickavel creates surreal yet tangible worlds, combining idiosyncratic, intense and eerie elements with unfiltered expression. Drawing from her ability to blur the lines between the surreal and the real, I infuse my stories with a sense of disquieting authenticity. Stephen Graham Jones stands out for his ability to explore morbid themes in a compelling and unconventional manner. His experimentation with horror fiction tropes, the visceral realism of his prose, and his complex characters inspire me to capture the unsettling feeling that something dreadful has occurred without explicitly detailing the facts and intricacies. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Namukuta, Sonia Charity Sajjabi
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435536 , vital:73166
- Description: My thesis is a collection of short stories that delve into the multifaceted nature of death, with a specific emphasis on murder, violence, death and their profound aftermath, including themes of loss, grief, and trauma. These stories offer diverse perspectives, narrated by perpetrators, voiceless victims, and those left to pick up the shattered pieces. Additionally, some stories are seen through the eyes of those tasked with handling the bodies. Often set in unnamed locations, they delve into imaginary and fantastical worlds, while remaining grounded in recognisable situations and spaces. I draw inspiration from popular and genre fiction such as horror, crime fiction and true crime stories, but approach my writing from a psychological lens, employing stylistic experimentation to challenge readers' expectations. The power of silence is a recurring motif. Rather than focusing on unearthing facts or revealing the "truth" like crime fiction often does, my narratives delve into what isn't or at times cannot be told — the unsayable. Some of my stories explore silence inherent in violence, grief, and the inability to articulate one's experience in the face of a violent act or a life prematurely ended. Others delve into the silence of untold stories and the dark secrets of the perpetrators. By exploring these contrasting perspectives, I aim to offer a nuanced exploration of death and its aftermath. The writing styles of Stephen Graham Jones, Lydia Davis, and Kuzhali Manickavel influence my work. Lydia Davis, known for her mastery of very short, flash fiction, ranging from single sentences to a paragraph or two, inspires me with her precise observations of the human condition. Her minimalist prose, carefully selecting and arranging words and sentences, encapsulates the power of less-is-more storytelling. Manickavel creates surreal yet tangible worlds, combining idiosyncratic, intense and eerie elements with unfiltered expression. Drawing from her ability to blur the lines between the surreal and the real, I infuse my stories with a sense of disquieting authenticity. Stephen Graham Jones stands out for his ability to explore morbid themes in a compelling and unconventional manner. His experimentation with horror fiction tropes, the visceral realism of his prose, and his complex characters inspire me to capture the unsettling feeling that something dreadful has occurred without explicitly detailing the facts and intricacies. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-04-04
Lemons or Lemonade? Examining the economic and social outcomes of engaging in the export-driven citrus value chain of South Africa for selected commercial citrus farmers and farm workers in the Raymond Mhlaba Municipal District, Eastern Cape
- Authors: Sizani, Simbulele
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435553 , vital:73168
- Description: This study examines the economic and social outcomes of participating in a global citrus value chain for selected commercial farmers and farm workers in Raymond Mhlaba Municipal District in the Eastern Cape, South Africa. A global chain refers to international production sharing through cross-border trade. Multilateral organizations (and some prominent global chain scholars) that support neoliberal economic globalization perceive global chains as ideal channels of economic and social upgrading for participants, particularly those from the global South. From the abovementioned perspective, global chains enhance efficiency through inter-firm relations that promote the distribution of technology and access to capital, thus leading to economic and social upgrading in developing countries. Economic upgrading, on the one hand, can briefly be described as the movement of supplier firms from lower to higher-value activities in global chains. Social upgrading, on the other hand, is the improvement of employment conditions and outcomes of workers employed by supplier firms at the production node of global chains. This study adopts the dual theoretical framework (Global Chain Framework and Labour Process Theory) proposed by Newsome, Taylor, Bair and Rainnie (2015) in their seminal book ‘Putting Labour in its Place: Labour Process Analysis and Global Value Chains’. This dual framework is ideal because it conceptualizes the spheres of trade exchange and production, which are the primary research sites of this study. Qualitative research methods were adopted and utilized to collect and analyse data in this study. These methods were ideal for this study, as they captured the subjective accounts of the selected commercial citrus farmers and farm workers in the Raymond Mhlaba Municipal District in the Eastern Cape, South Africa. The findings in this study showed that the outcomes of these selected commercial citrus farmers and farm workers in this region are variegated, meaning that, there is evidence of economic upgrading, social upgrading and social downgrading as well. Amongst farm workers in the region, only a small group of (mostly older male) farm workers enjoyed social upgrading, whilst the majority of seasonal (mostly female) farm workers experiences social downgrading. The findings in this study showed that the variegated economic and social outcomes of the selected commercial farmers and farm workers were primarily determined by their economic class and position within the citrus value chain of South Africa. These findings highlight the importance of positionality in determining the fate of participants in global chains. , Thesis (MA) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Sizani, Simbulele
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435553 , vital:73168
- Description: This study examines the economic and social outcomes of participating in a global citrus value chain for selected commercial farmers and farm workers in Raymond Mhlaba Municipal District in the Eastern Cape, South Africa. A global chain refers to international production sharing through cross-border trade. Multilateral organizations (and some prominent global chain scholars) that support neoliberal economic globalization perceive global chains as ideal channels of economic and social upgrading for participants, particularly those from the global South. From the abovementioned perspective, global chains enhance efficiency through inter-firm relations that promote the distribution of technology and access to capital, thus leading to economic and social upgrading in developing countries. Economic upgrading, on the one hand, can briefly be described as the movement of supplier firms from lower to higher-value activities in global chains. Social upgrading, on the other hand, is the improvement of employment conditions and outcomes of workers employed by supplier firms at the production node of global chains. This study adopts the dual theoretical framework (Global Chain Framework and Labour Process Theory) proposed by Newsome, Taylor, Bair and Rainnie (2015) in their seminal book ‘Putting Labour in its Place: Labour Process Analysis and Global Value Chains’. This dual framework is ideal because it conceptualizes the spheres of trade exchange and production, which are the primary research sites of this study. Qualitative research methods were adopted and utilized to collect and analyse data in this study. These methods were ideal for this study, as they captured the subjective accounts of the selected commercial citrus farmers and farm workers in the Raymond Mhlaba Municipal District in the Eastern Cape, South Africa. The findings in this study showed that the outcomes of these selected commercial citrus farmers and farm workers in this region are variegated, meaning that, there is evidence of economic upgrading, social upgrading and social downgrading as well. Amongst farm workers in the region, only a small group of (mostly older male) farm workers enjoyed social upgrading, whilst the majority of seasonal (mostly female) farm workers experiences social downgrading. The findings in this study showed that the variegated economic and social outcomes of the selected commercial farmers and farm workers were primarily determined by their economic class and position within the citrus value chain of South Africa. These findings highlight the importance of positionality in determining the fate of participants in global chains. , Thesis (MA) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-04-04
Managing releases of Anagyrus vladimiri (Triapitsyn) to augment biocontrol of the citrus mealybug Planococcus citri (Risso) in South African citrus orchards
- Authors: Mommsen, Wayne Trevor
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434952 , vital:73118
- Description: In May 2019, South Korean inspectors rejected numerous grapefruit consignments from Letsitele, Hoedspruit and Onderberg in South Arica, because of live mealybug found on fruit. Growers expressed deep concern as mealybug management to a phytosanitary level was almost unattainable. Regular spray interventions for control of citrus black spot fungus, Phyllosticta citricarpa, and citrus thrips, Scirtothrips aurantii, cause repercussions in mealybug populations because they undermine the naturally occurring biocontrol complex. As part of an Integrated Pest Management (IPM) strategy, release of commercially produced parasitoids is common practice, to augment the naturally occurring beneficial insect populations. Prior knowledge of the harmful effects of insecticides on parasitoids is essential to IPM planning and the success of the biocontrol component in such a programme. Timing of augmentative releases to coincide with the phenology of citrus and the mealybug pest is also considered important for the successful establishment and control. Consequently, field trials were conducted to compare efficacy of early vs. late releases of Anagyrus vladimiri (Triapitsyn), an effective parasitoid of the citrus mealybug, Planococcus citri (Risso). Semi-field bioassays were conducted concurrently to determine the impact of various thripicides on A. vladimiri. The impact of sulfoxaflor, spinetoram, spirotetramat and prothiofos were rated harmless, as A. vladimiri mortality was lower than 25% after coming into contact with aged residues between 7 and 14 days old. October and November releases of A. vladimiri resulted in early parasitism and lowered peak-infestation of mealybug. January releases are possibly too late in grapefruit and lemon, open field, orchards, considering parasitism by A. vladimiri peaked in February. In mandarin orchards under net, percentage parasitism of 3rd instar mealybug increased a month later. Notably, at harvest, the difference in efficacy between treatments was not clear. This could be explained by high levels of natural parasitism observed in the treated and untreated orchards, which emphasises the importance of conservation biocontrol. In a second season, the proportion of hyperparasitoids captured (61%) from samples of mealybug-infested fruit was larger than the proportion of primary parasitoids, Anagyrus vladimiri, Coccidoxenoides perminutus (Girault) and Leptomastix dactylopii (Howard) (39%), which was far lower than the captures of eclosing primary parasitoids the previous season, which was 60%. The new discovery of Pseudaphycus sp. in citrus orchards in South Africa could be a key in explaining the uncontrollable levels of mealybug experienced and has drawn attention to a need for further understanding of ecological factors that influence biological control in citrus. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Mommsen, Wayne Trevor
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434952 , vital:73118
- Description: In May 2019, South Korean inspectors rejected numerous grapefruit consignments from Letsitele, Hoedspruit and Onderberg in South Arica, because of live mealybug found on fruit. Growers expressed deep concern as mealybug management to a phytosanitary level was almost unattainable. Regular spray interventions for control of citrus black spot fungus, Phyllosticta citricarpa, and citrus thrips, Scirtothrips aurantii, cause repercussions in mealybug populations because they undermine the naturally occurring biocontrol complex. As part of an Integrated Pest Management (IPM) strategy, release of commercially produced parasitoids is common practice, to augment the naturally occurring beneficial insect populations. Prior knowledge of the harmful effects of insecticides on parasitoids is essential to IPM planning and the success of the biocontrol component in such a programme. Timing of augmentative releases to coincide with the phenology of citrus and the mealybug pest is also considered important for the successful establishment and control. Consequently, field trials were conducted to compare efficacy of early vs. late releases of Anagyrus vladimiri (Triapitsyn), an effective parasitoid of the citrus mealybug, Planococcus citri (Risso). Semi-field bioassays were conducted concurrently to determine the impact of various thripicides on A. vladimiri. The impact of sulfoxaflor, spinetoram, spirotetramat and prothiofos were rated harmless, as A. vladimiri mortality was lower than 25% after coming into contact with aged residues between 7 and 14 days old. October and November releases of A. vladimiri resulted in early parasitism and lowered peak-infestation of mealybug. January releases are possibly too late in grapefruit and lemon, open field, orchards, considering parasitism by A. vladimiri peaked in February. In mandarin orchards under net, percentage parasitism of 3rd instar mealybug increased a month later. Notably, at harvest, the difference in efficacy between treatments was not clear. This could be explained by high levels of natural parasitism observed in the treated and untreated orchards, which emphasises the importance of conservation biocontrol. In a second season, the proportion of hyperparasitoids captured (61%) from samples of mealybug-infested fruit was larger than the proportion of primary parasitoids, Anagyrus vladimiri, Coccidoxenoides perminutus (Girault) and Leptomastix dactylopii (Howard) (39%), which was far lower than the captures of eclosing primary parasitoids the previous season, which was 60%. The new discovery of Pseudaphycus sp. in citrus orchards in South Africa could be a key in explaining the uncontrollable levels of mealybug experienced and has drawn attention to a need for further understanding of ecological factors that influence biological control in citrus. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
MeerKAT observations of the Abell 141 galaxy cluster
- Authors: Stanbury, Savannah Mae
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435378 , vital:73152
- Description: This study is aimed at being an overview and investigation of the behaviour and morphology of radio quiet (RQ) active galactic nuclei (AGN) in the radio and optical/near-infrared (NIR) bands. It is hoped that a concise description of the relation that exists between accretion activity and star formation (SF) will be achieved through utilization of multiwavelength astronomy analysis. This analysis includes the processing of data acquired from the MeerKAT International GHz Tiered Extragalactic Exploration survey (MIGHTEE), the Southern African Large Telescope (SALT), the Hyper Suprime Camera (HSC) mounted on the Subaru telescope and the VISTA telescope. In this thesis, several targets were observed using SALT spectroscopy, but a redshift of only one of them was obtained. Lastly, it was established that for the sample of RQ AGN studied, the AGN contribute a large fraction of the radio emission observed. , Thesis (MSc) -- Faculty of Science, Physics and Electronics, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Stanbury, Savannah Mae
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435378 , vital:73152
- Description: This study is aimed at being an overview and investigation of the behaviour and morphology of radio quiet (RQ) active galactic nuclei (AGN) in the radio and optical/near-infrared (NIR) bands. It is hoped that a concise description of the relation that exists between accretion activity and star formation (SF) will be achieved through utilization of multiwavelength astronomy analysis. This analysis includes the processing of data acquired from the MeerKAT International GHz Tiered Extragalactic Exploration survey (MIGHTEE), the Southern African Large Telescope (SALT), the Hyper Suprime Camera (HSC) mounted on the Subaru telescope and the VISTA telescope. In this thesis, several targets were observed using SALT spectroscopy, but a redshift of only one of them was obtained. Lastly, it was established that for the sample of RQ AGN studied, the AGN contribute a large fraction of the radio emission observed. , Thesis (MSc) -- Faculty of Science, Physics and Electronics, 2024
- Full Text:
- Date Issued: 2024-04-04
Paul and the soul: an analysis of the Apostle’s anthropology
- Authors: Pluke, Dylan Hay
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435506 , vital:73164
- Description: It may be no exaggeration to say that every aspect of the Apostle Paul’s thought is debated. This is certainly the case for his anthropology, which is to say his beliefs regarding the nature of the human person. There is intense debate concerning what Paul believed about the human person. This is especially so when arguing about whether or not Paul believed in a human soul. In the thesis that follows, I use a linguistic analysis of Paul’s writings as well as those of two of his putative backgrounds, to determine what he believed regarding the nature of the human soul. The results of this analysis are that, of the potential backgrounds that may have influenced the Apostle, the Jewish background into which he was born is the most pertinent, and that neither of the two words that Paul uses mean soul, in the sense of something which is immaterial and survives death. Rather, the psyche refers to one’s life, and the pneuma to the part of the person that connects one with God and which will replace the psyche and animate the person in the new age to come. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Pluke, Dylan Hay
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435506 , vital:73164
- Description: It may be no exaggeration to say that every aspect of the Apostle Paul’s thought is debated. This is certainly the case for his anthropology, which is to say his beliefs regarding the nature of the human person. There is intense debate concerning what Paul believed about the human person. This is especially so when arguing about whether or not Paul believed in a human soul. In the thesis that follows, I use a linguistic analysis of Paul’s writings as well as those of two of his putative backgrounds, to determine what he believed regarding the nature of the human soul. The results of this analysis are that, of the potential backgrounds that may have influenced the Apostle, the Jewish background into which he was born is the most pertinent, and that neither of the two words that Paul uses mean soul, in the sense of something which is immaterial and survives death. Rather, the psyche refers to one’s life, and the pneuma to the part of the person that connects one with God and which will replace the psyche and animate the person in the new age to come. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-04-04
Perceptions of registered counselors’ ability to process clients’ narrated dreams during counselling
- Authors: Mpondo, Nontutuzelo
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435468 , vital:73160
- Description: Research related to South African registered counsellors (RCs) have yet to show how RCs incorporate dreamwork in their counselling sessions. Dreamwork has largely been relegated to the periphery of clinical psychological practice, posing a challenge as clients on other levels of counselling practice bring dream material to mental health practitioners often lacking confidence and competence to respond effectively to this material. Clients' discussion of dreams can be beneficial in the counselling process. However, there appears to be a gap in educational opportunities for practitioners to develop skills and competency in working with dreams. This study's objective was to contribute to the sparse research material in this area. A qualitative research approach with an exploratory design using semi-structured interviews was used to explore and understand the meaning RCs ascribed to their work with dreams and clients. Purposive sampling was used to recruit 5 participants. Social constructionism was used as a theoretical framework for understanding and interpreting the data, and the data was analysed using thematic analysis. This knowledge is geared towards providing insight into what extent university or college curriculum covered content related to dreams, dreamwork, dream theories, and dream models, and to what extent RC's training prepared them to provide essential primary psychological services related to distress arising from dreams. This research highlighted how RCs engaged and perceived their competency with dream material. This study also highlighted that RCs were interested in dreamwork training and believed it would enhance their confidence and effectiveness in working with dream material during their sessions. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-04-04
Perceptions of registered counselors’ ability to process clients’ narrated dreams during counselling
- Authors: Mpondo, Nontutuzelo
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435468 , vital:73160
- Description: Research related to South African registered counsellors (RCs) have yet to show how RCs incorporate dreamwork in their counselling sessions. Dreamwork has largely been relegated to the periphery of clinical psychological practice, posing a challenge as clients on other levels of counselling practice bring dream material to mental health practitioners often lacking confidence and competence to respond effectively to this material. Clients' discussion of dreams can be beneficial in the counselling process. However, there appears to be a gap in educational opportunities for practitioners to develop skills and competency in working with dreams. This study's objective was to contribute to the sparse research material in this area. A qualitative research approach with an exploratory design using semi-structured interviews was used to explore and understand the meaning RCs ascribed to their work with dreams and clients. Purposive sampling was used to recruit 5 participants. Social constructionism was used as a theoretical framework for understanding and interpreting the data, and the data was analysed using thematic analysis. This knowledge is geared towards providing insight into what extent university or college curriculum covered content related to dreams, dreamwork, dream theories, and dream models, and to what extent RC's training prepared them to provide essential primary psychological services related to distress arising from dreams. This research highlighted how RCs engaged and perceived their competency with dream material. This study also highlighted that RCs were interested in dreamwork training and believed it would enhance their confidence and effectiveness in working with dream material during their sessions. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-04-04
Performance evaluation of baseline-dependent window functions with several weighing functions
- Authors: Vanqa, Kamvulethu
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435850 , vital:73206
- Description: Radio interferometric data volume is exponentially increasing with the potential to cause slow processing and data storage issues for radio observations recorded at high time and frequency resolutions. This necessitates that a sort of data compression is imposed. The conventional method to compress the data is averaging across time and frequency. However, this results in amplitude loss and source distortion at the edges of the field of view. To reduce amplitude loss and source distortion, baseline-dependent window functions (BDWFs) are proposed in theliterature. BDWFs are visibility data compression methods using window functions to retainthe signals within a field of interest (FoI) and to suppress signals outside this FoI. However,BDWFs are used with window functions as discussed in the signal processing field without any optimisation. This thesis evaluates the performance of BDWFs and then proposes to use machine learning with gradient descent to optimize the window functions employed in BDWFs. Results show that the convergence of the objective function is limited due to the band-limited nature of the window functions in the Fourier space. BDWFs performance is also investigated and discussed using several weighting schemes. Results show that there exists an optimal parameter tuning (not necessarily unique) that suggests an optimal combination of BDWFs and density sampling. With this, ∼ 4 % smearing is observed within the FoI, and ∼ 80 % source suppression is achieved outside the FoI using the MeerKAT telescope at 1.4 GHz, sampled at 1 s and 184.3 kHz then averaged with BDWFs to achieve a compression factor of 4 in time and 3 in frequency. , Thesis (MA) -- Faculty of Science, Mathematics, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Vanqa, Kamvulethu
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435850 , vital:73206
- Description: Radio interferometric data volume is exponentially increasing with the potential to cause slow processing and data storage issues for radio observations recorded at high time and frequency resolutions. This necessitates that a sort of data compression is imposed. The conventional method to compress the data is averaging across time and frequency. However, this results in amplitude loss and source distortion at the edges of the field of view. To reduce amplitude loss and source distortion, baseline-dependent window functions (BDWFs) are proposed in theliterature. BDWFs are visibility data compression methods using window functions to retainthe signals within a field of interest (FoI) and to suppress signals outside this FoI. However,BDWFs are used with window functions as discussed in the signal processing field without any optimisation. This thesis evaluates the performance of BDWFs and then proposes to use machine learning with gradient descent to optimize the window functions employed in BDWFs. Results show that the convergence of the objective function is limited due to the band-limited nature of the window functions in the Fourier space. BDWFs performance is also investigated and discussed using several weighting schemes. Results show that there exists an optimal parameter tuning (not necessarily unique) that suggests an optimal combination of BDWFs and density sampling. With this, ∼ 4 % smearing is observed within the FoI, and ∼ 80 % source suppression is achieved outside the FoI using the MeerKAT telescope at 1.4 GHz, sampled at 1 s and 184.3 kHz then averaged with BDWFs to achieve a compression factor of 4 in time and 3 in frequency. , Thesis (MA) -- Faculty of Science, Mathematics, 2024
- Full Text:
- Date Issued: 2024-04-04
Political competition and local government debt: implications for human development: A case study of Eastern Cape municipalities
- Authors: Matapuri, Fadzai Valerie
- Date: 2024-04-04
- Subjects: Local government South Africa Eastern Cape , Municipal finance South Africa Eastern Cape , Public administration South Africa Eastern Cape , Municipal services South Africa Eastern Cape , Electoral competition , Human development
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435874 , vital:73208
- Description: South African Municipalities are currently in a precarious financial situation. The financial distress has intensified so much that local governments are on the brink of collapse. Municipalities in South Africa currently owe over 35.5 billion rands. Reports from the Auditor-General of South Africa portrayed a grim picture of the state of financial affairs in municipalities; only 33 municipalities out of 278 had received a clean audit, with over 30 billion rands in expenditure declared irregular. The report further revealed that there were numerous cases of non-compliance with key legislation in municipalities. The poor financial audits across the country have stressed the severe lack of accountability, government issues and political turmoil. Due to this state of affairs, municipalities cannot deliver services such as sanitation, electricity, and water. As a result, many service delivery protests have occurred over the years. Political factors have been highlighted as the leading cause of these local government woes. This study aims to investigate the relationship between political competition and local government debt and its effect on human development in Eastern Cape municipalities. The study used a panel data set for 32 municipalities and electoral data from 2009 to 2016. The panel vector autoregression model, generalized least squares, fixed and random effects methods were used to investigate the relationship between political competition and local government debt. The study found a positive unidirectional relationship between political competition and local debt. This was found using the normalized Herfindahl index, debt to asset, tress index, human development index, population and poverty variables. Moreover, estimated results showed that local governments in the eastern cape were characterised by a political monopoly that, in turn, increased local government debt through growth-hindering policies adopted by political leaders. Resulting in economic concentration, which hinders local economic growth and human development. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Matapuri, Fadzai Valerie
- Date: 2024-04-04
- Subjects: Local government South Africa Eastern Cape , Municipal finance South Africa Eastern Cape , Public administration South Africa Eastern Cape , Municipal services South Africa Eastern Cape , Electoral competition , Human development
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435874 , vital:73208
- Description: South African Municipalities are currently in a precarious financial situation. The financial distress has intensified so much that local governments are on the brink of collapse. Municipalities in South Africa currently owe over 35.5 billion rands. Reports from the Auditor-General of South Africa portrayed a grim picture of the state of financial affairs in municipalities; only 33 municipalities out of 278 had received a clean audit, with over 30 billion rands in expenditure declared irregular. The report further revealed that there were numerous cases of non-compliance with key legislation in municipalities. The poor financial audits across the country have stressed the severe lack of accountability, government issues and political turmoil. Due to this state of affairs, municipalities cannot deliver services such as sanitation, electricity, and water. As a result, many service delivery protests have occurred over the years. Political factors have been highlighted as the leading cause of these local government woes. This study aims to investigate the relationship between political competition and local government debt and its effect on human development in Eastern Cape municipalities. The study used a panel data set for 32 municipalities and electoral data from 2009 to 2016. The panel vector autoregression model, generalized least squares, fixed and random effects methods were used to investigate the relationship between political competition and local government debt. The study found a positive unidirectional relationship between political competition and local debt. This was found using the normalized Herfindahl index, debt to asset, tress index, human development index, population and poverty variables. Moreover, estimated results showed that local governments in the eastern cape were characterised by a political monopoly that, in turn, increased local government debt through growth-hindering policies adopted by political leaders. Resulting in economic concentration, which hinders local economic growth and human development. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2024
- Full Text:
- Date Issued: 2024-04-04
Social justice implications of the language of the court judgment genre and its development in pre- and post-independence Zimbabwe
- Authors: Nemaramba, Dylan
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435605 , vital:73172
- Description: Access restricted. Expected release in 2026. , Thesis (PhD) -- Humanities, Linguistics and Applied Language Studies, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Nemaramba, Dylan
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435605 , vital:73172
- Description: Access restricted. Expected release in 2026. , Thesis (PhD) -- Humanities, Linguistics and Applied Language Studies, 2024
- Full Text:
- Date Issued: 2024-04-04
The effect of Gracilaria gracilis (Rhodophyta) on growth and behaviour of farmed abalone Haliotis midae when included in the abalone diet
- Madlala, Njabulo Praiseworth
- Authors: Madlala, Njabulo Praiseworth
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435332 , vital:73148
- Description: Abalone feed naturally on algae, but commercial abalone farms rely on formulated feed. The inclusion of algae with the formulated feed in the diet improves growth, health and feed conversion ratio (FCR). However, the kelp that is currently included in the feed is wild harvested and this resource is limited and under increasing pressure. Thus, there is a need to develop an alternative sustainable source of algae. The aim was to use Gracilaria gracilis algae (that was produced with mussel in an integrated multitrophic aquaculture system; IMTA) which was then included into abalone feeds and its influence on abalone growth, FCR and behaviour was evaluated. Sea-based G. gracilis was harvested off an existing IMTA system, manufactured into Abfeed® and fed to abalone to determine growth efficiency. Abalone (30 - 40 g abalone-1) originated from the same cohort at Whale Rock Abalone Farm (Pty) Ltd., Hermanus. Abalone were fed either: Abfeed® S34 only with no algae (G0, the control); Abfeed® with sea-based IMTA G. gracilis included in the formulated feed at 0.75 % (G0.75); 1.50 % (G1.50); 3.00 % (G3.00); 6.00 % (G6.00); and 12.00 % (G12.00) inclusion; and Abfeed® S34 with fresh-live G. gracilis (cultured at Whale Rock Abalone Farm (Pty) Ltd.; Gfresh + S34s). Abalone shell length, whole body mass and FCR were measured at a four-months interval over eight months (two growth cycles). Differences in behaviour (i.e., level of activity and feeding activity) were also monitored and comparing between treatments. There was significant difference in mean whole-body mass between treatments (RMANOVA, F(6, 29) = 3.71, p = 0.007). Abalone fed the diet with the highest inclusion of dry G. gracilis (G12.00) had a lower mean whole-body mass value (74.13 ± 2.94 g abalone-1) than abalone from all the other diets after eight months. There was a negative relationship between the condition factor and dry G. gracilis inclusion rate for the first growth cycle (y = - 0.0044x + 1.222, R2 = 0.24, p=0.009) and second-growth cycle (y = - 0.0096x + 1.2233, R2 = 0.51, p = 0.00002). Abalone receiving fresh G. gracilis were less quiescent and more alert on the first hours after food distribution (p < 0.05). The same proportion of abalone with G0, G0.75, and G6.00 G. gracilis inclusion were feeding all along the 9 hours post-feeding. This study will potentially reduce the dependence of abalone farms on wild-harvested kelp in formulated feed. This will improve their contribution to a more environmentally sustainable global production of sea food products, making them more competitive on international markets. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Madlala, Njabulo Praiseworth
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435332 , vital:73148
- Description: Abalone feed naturally on algae, but commercial abalone farms rely on formulated feed. The inclusion of algae with the formulated feed in the diet improves growth, health and feed conversion ratio (FCR). However, the kelp that is currently included in the feed is wild harvested and this resource is limited and under increasing pressure. Thus, there is a need to develop an alternative sustainable source of algae. The aim was to use Gracilaria gracilis algae (that was produced with mussel in an integrated multitrophic aquaculture system; IMTA) which was then included into abalone feeds and its influence on abalone growth, FCR and behaviour was evaluated. Sea-based G. gracilis was harvested off an existing IMTA system, manufactured into Abfeed® and fed to abalone to determine growth efficiency. Abalone (30 - 40 g abalone-1) originated from the same cohort at Whale Rock Abalone Farm (Pty) Ltd., Hermanus. Abalone were fed either: Abfeed® S34 only with no algae (G0, the control); Abfeed® with sea-based IMTA G. gracilis included in the formulated feed at 0.75 % (G0.75); 1.50 % (G1.50); 3.00 % (G3.00); 6.00 % (G6.00); and 12.00 % (G12.00) inclusion; and Abfeed® S34 with fresh-live G. gracilis (cultured at Whale Rock Abalone Farm (Pty) Ltd.; Gfresh + S34s). Abalone shell length, whole body mass and FCR were measured at a four-months interval over eight months (two growth cycles). Differences in behaviour (i.e., level of activity and feeding activity) were also monitored and comparing between treatments. There was significant difference in mean whole-body mass between treatments (RMANOVA, F(6, 29) = 3.71, p = 0.007). Abalone fed the diet with the highest inclusion of dry G. gracilis (G12.00) had a lower mean whole-body mass value (74.13 ± 2.94 g abalone-1) than abalone from all the other diets after eight months. There was a negative relationship between the condition factor and dry G. gracilis inclusion rate for the first growth cycle (y = - 0.0044x + 1.222, R2 = 0.24, p=0.009) and second-growth cycle (y = - 0.0096x + 1.2233, R2 = 0.51, p = 0.00002). Abalone receiving fresh G. gracilis were less quiescent and more alert on the first hours after food distribution (p < 0.05). The same proportion of abalone with G0, G0.75, and G6.00 G. gracilis inclusion were feeding all along the 9 hours post-feeding. This study will potentially reduce the dependence of abalone farms on wild-harvested kelp in formulated feed. This will improve their contribution to a more environmentally sustainable global production of sea food products, making them more competitive on international markets. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-04-04