Investigating teachers’ perceptions on translanguaging pedagogy in a multilingual intermediate ESL classroom: a comparative study of two primary schools in Namibia
- Authors: Rheeder, Veneza Memory
- Date: 2023-10-13
- Subjects: Translanguaging (Linguistics) , Second language acquisition , Multilingual education Namibia , Primary school teachers Attitudes , Native language and education Namibia , Primary school teaching Namibia
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/419760 , vital:71673
- Description: International literature has tested the effectiveness of translanguaging as a pedagogic tool to enhance learning in a bilingual classroom; however, with the recent curriculum reform and education sector policy, there is no direct claim in the National policy frameworks on the prominence of translanguaging as an effective tool in classroom pedagogy in Namibian schools. This research attempted to investigate the role of translanguaging as a pedagogic tool to enhance learning in the multilingual intermediate English Second Language (ESL) phase as the Language of Learning and Teaching (LoLT) for the intermediate phase, Grades 4-7, in the Erongo Region, Namibia. The study is within the interpretive paradigm and adopts a qualitative methodology using a qualitative multi-case study approach of exploring and understanding differences and similarities between cases. Data collection consisted mainly of open-ended interviews and observations (purposive sampling) of the participating teachers. The research sites and study participants were purposely selected as both schools, diversely located in urban and rural contexts of the region, are enacting the National Language Policy as proposed. This entails using Mother Tongue Instruction (MTI) from Grades 0-3 and then transitioning to English-monolingual instruction from Grades 4 onwards. The study was designed to investigate the role of translanguaging pedagogy in enhancing learning in the Second Language (L2) classroom, without prejudice of social classes - the elite and marginalized communities. It investigated the extent to which teachers’ use of translanguaging pedagogy enhances ESL learning as the LoLT to intermediate phase learners transitioning from MTI to English-only instruction. The main theories underpinning this study are the Vygotskian and Translanguaging theories supported by Krashen and Cummins’ Cognitive Underlying Proficiency (CUP) Model. The outcomes of the study reveal that in both schools translanguaging was supported by content subject teachers and English LoLT teachers and that it positively contributed to improving learner understanding of important concepts in several subjects. However, Mother Tongue (MT) teachers did not support the use of translanguaging and believed that it slowed down the learning of English. , Thesis (MEd) -- Faculty of Education, Institute for the Study of Englishes in Africa, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Rheeder, Veneza Memory
- Date: 2023-10-13
- Subjects: Translanguaging (Linguistics) , Second language acquisition , Multilingual education Namibia , Primary school teachers Attitudes , Native language and education Namibia , Primary school teaching Namibia
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/419760 , vital:71673
- Description: International literature has tested the effectiveness of translanguaging as a pedagogic tool to enhance learning in a bilingual classroom; however, with the recent curriculum reform and education sector policy, there is no direct claim in the National policy frameworks on the prominence of translanguaging as an effective tool in classroom pedagogy in Namibian schools. This research attempted to investigate the role of translanguaging as a pedagogic tool to enhance learning in the multilingual intermediate English Second Language (ESL) phase as the Language of Learning and Teaching (LoLT) for the intermediate phase, Grades 4-7, in the Erongo Region, Namibia. The study is within the interpretive paradigm and adopts a qualitative methodology using a qualitative multi-case study approach of exploring and understanding differences and similarities between cases. Data collection consisted mainly of open-ended interviews and observations (purposive sampling) of the participating teachers. The research sites and study participants were purposely selected as both schools, diversely located in urban and rural contexts of the region, are enacting the National Language Policy as proposed. This entails using Mother Tongue Instruction (MTI) from Grades 0-3 and then transitioning to English-monolingual instruction from Grades 4 onwards. The study was designed to investigate the role of translanguaging pedagogy in enhancing learning in the Second Language (L2) classroom, without prejudice of social classes - the elite and marginalized communities. It investigated the extent to which teachers’ use of translanguaging pedagogy enhances ESL learning as the LoLT to intermediate phase learners transitioning from MTI to English-only instruction. The main theories underpinning this study are the Vygotskian and Translanguaging theories supported by Krashen and Cummins’ Cognitive Underlying Proficiency (CUP) Model. The outcomes of the study reveal that in both schools translanguaging was supported by content subject teachers and English LoLT teachers and that it positively contributed to improving learner understanding of important concepts in several subjects. However, Mother Tongue (MT) teachers did not support the use of translanguaging and believed that it slowed down the learning of English. , Thesis (MEd) -- Faculty of Education, Institute for the Study of Englishes in Africa, 2023
- Full Text:
- Date Issued: 2023-10-13
Investigation into methods of recovering campylobacter spp. from river water samples
- Authors: Ngoni, Nandipha
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424177 , vital:72130
- Description: Campylobacter species are slender, gram-negative, rod-shaped, spiral- or curved-shaped with single or pairs of flagella. They are the leading cause of diarrheal disease globally, consumption of and contact with water contaminated by faeces is a major risk factor for transmission of these organisms to humans. Rivers used for recreation and domestic and agricultural activities represent all the risk factors for Campylobacter spp. pollution and human exposure. Campylobacter spp. However, effective methods to recover Campylobacter spp. from river water samples are lacking, indicating the need for the development of more efficient methods of detection and isolation of these organisms from environmental water samples. Campylobacter detection in a water sample is critical to ascertain potential risks to humans. The aim of this study was to determine a suitable method for the detection of Campylobacter spp. from river water samples and the objectives were to (i) to evaluate the performance of different methods used for the recovery of Campylobacter spp. from environmental water samples based on Campylobacter colony count and PCR identification results, (ii) isolate and enumerate Campylobacter cells from river water samples, and (iii) identify Campylobacter spp. in river water samples. The Bloukrans River was chosen for this study because it is suspected to be contaminated by faecal inputs from nearby informal settlements without adequate sanitation, as well as untreated/insufficiently treated effluents from nearby wastewater treatment plants. First, the physicochemical quality of the river water and the presence of faecal contamination were assessed to confirm suitability for Campylobacter spp. survival and presence. Then different approaches to sample, concentrate and recover Campylobacter spp. from river water samples were assessed. The different methods assessed were (i) direct enrichment of water samples without prior concentration, (ii) prior concentration of water samples by centrifugation followed by membrane filtration of supernatant, and after that, pooling the residue and pellet together for enrichment, (iii) sampling by the Moore Swab technique. For all three methods, enrichment in Bolton broth supplemented with Bolton antibiotics was conducted. This was followed by plating on modified cefoperazone charcoal deoxycholate agar (mCCDA) and incubation under a microaerophilic atmosphere at 42°C for 48 h. Colony morphology, Gram staining and polymerase chain reaction (PCR) were used to identify and characterize the microorganisms. The growth of blue colonies on the mFc agar surface confirmed presence and faecal pollution of the Bloukrans River. The physicochemical properties, based on the range of pH measured at different sites of the river (between acidic 3.45 to 6.42 and alkaline 7.2 to 8.74) indicate that Campylobacter spp. can thrive in the river. Based on the results from enumeration and sequencing of colonies recovered by each method, it was discovered that the most suitable method to recover Campylobacter spp. from river water samples is by prior centrifugation (14,000 × g for 30 minutes) followed by membrane filtration of the supernatant, and subsequent pooling of the residue and pellet. The pooled residue and pellet might have increased Campylobacter spp. concentrations aiding more growth during the enrichment of Campylobacter spp. from the river water samples. Results from enumerating Campylobacter spp. cells from river water samples indicate that Campylobacter spp. are present in Bloukrans River. The sequence obtained from the PCR product indicates that the species found were Campylobacter jejuni (96% homology as evaluated by BLAST). This study provided a procedure effective for obtaining a satisfactory quantitative recovery of Campylobacter spp. from environmental waters, a critical need for quantitative microbial risk assessment studies. , Thesis (MSc) -- Faculty of Science, Institute for Water Research, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Ngoni, Nandipha
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424177 , vital:72130
- Description: Campylobacter species are slender, gram-negative, rod-shaped, spiral- or curved-shaped with single or pairs of flagella. They are the leading cause of diarrheal disease globally, consumption of and contact with water contaminated by faeces is a major risk factor for transmission of these organisms to humans. Rivers used for recreation and domestic and agricultural activities represent all the risk factors for Campylobacter spp. pollution and human exposure. Campylobacter spp. However, effective methods to recover Campylobacter spp. from river water samples are lacking, indicating the need for the development of more efficient methods of detection and isolation of these organisms from environmental water samples. Campylobacter detection in a water sample is critical to ascertain potential risks to humans. The aim of this study was to determine a suitable method for the detection of Campylobacter spp. from river water samples and the objectives were to (i) to evaluate the performance of different methods used for the recovery of Campylobacter spp. from environmental water samples based on Campylobacter colony count and PCR identification results, (ii) isolate and enumerate Campylobacter cells from river water samples, and (iii) identify Campylobacter spp. in river water samples. The Bloukrans River was chosen for this study because it is suspected to be contaminated by faecal inputs from nearby informal settlements without adequate sanitation, as well as untreated/insufficiently treated effluents from nearby wastewater treatment plants. First, the physicochemical quality of the river water and the presence of faecal contamination were assessed to confirm suitability for Campylobacter spp. survival and presence. Then different approaches to sample, concentrate and recover Campylobacter spp. from river water samples were assessed. The different methods assessed were (i) direct enrichment of water samples without prior concentration, (ii) prior concentration of water samples by centrifugation followed by membrane filtration of supernatant, and after that, pooling the residue and pellet together for enrichment, (iii) sampling by the Moore Swab technique. For all three methods, enrichment in Bolton broth supplemented with Bolton antibiotics was conducted. This was followed by plating on modified cefoperazone charcoal deoxycholate agar (mCCDA) and incubation under a microaerophilic atmosphere at 42°C for 48 h. Colony morphology, Gram staining and polymerase chain reaction (PCR) were used to identify and characterize the microorganisms. The growth of blue colonies on the mFc agar surface confirmed presence and faecal pollution of the Bloukrans River. The physicochemical properties, based on the range of pH measured at different sites of the river (between acidic 3.45 to 6.42 and alkaline 7.2 to 8.74) indicate that Campylobacter spp. can thrive in the river. Based on the results from enumeration and sequencing of colonies recovered by each method, it was discovered that the most suitable method to recover Campylobacter spp. from river water samples is by prior centrifugation (14,000 × g for 30 minutes) followed by membrane filtration of the supernatant, and subsequent pooling of the residue and pellet. The pooled residue and pellet might have increased Campylobacter spp. concentrations aiding more growth during the enrichment of Campylobacter spp. from the river water samples. Results from enumerating Campylobacter spp. cells from river water samples indicate that Campylobacter spp. are present in Bloukrans River. The sequence obtained from the PCR product indicates that the species found were Campylobacter jejuni (96% homology as evaluated by BLAST). This study provided a procedure effective for obtaining a satisfactory quantitative recovery of Campylobacter spp. from environmental waters, a critical need for quantitative microbial risk assessment studies. , Thesis (MSc) -- Faculty of Science, Institute for Water Research, 2023
- Full Text:
- Date Issued: 2023-10-13
Investigation of brewery waste grains and microbial fuel cells as value-additive technologies improving solvent production yields in Clostridium acetobutylicum (ATCC 824) fermentation
- Authors: Du Toit, Ryan Guillaume
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424643 , vital:72171
- Description: The production of the solvent compounds acetone, ethanol and butanol through fermentation of organic feedstocks using Clostridia species could be a promising route for biofuel production. However, the cost of raw materials, low yields and the complexity of anaerobic fermentation continue to hinder this means of generating these compounds. The research presented in this Thesis investigated low-cost interventions that could decrease the costs of production and to direct the synthesis of fuel compounds using microbial fuel cells. Low-cost anaerobic chambers were designed and constructed for the propagation and manipulation of Clostridium acetobutylicum, selected as a low-risk microbial catalyst. Fermentation was monitored using in situ pH measurements and a combination of turbidity measurements, nutrient assays (especially total carbohydrates) and HPLC-RI detection as a means of monitoring the consumption of nutrients (glucose), production of precursor compounds (butyric acid) and the formation of solvent molecules (acetone/ethanol and butanol) during fermentation by this organism. Brewer’s spent grains were tested as a sustainable and low-cost feedstock for solvent production, comparing the effects of sterilising before fermentation, or allowing resident microflora to remain during Clostridium-catalysed solvent production. Sterilised spent grains significantly improved the production of solvent molecules (e.g. 12.97 ± 0.38 g/L of butanol yielded, compared to 0.40 ± 0.33 g/L for defined media sampled during the solventogenic phase); compared to these, the use of non-sterilised brewer’s grain decreased both the reproducibility and yields of fermentation (8.66 ± 1.6 g/L of butanol). Microbial fuel cells were studied as a possible means of altering electron transfer to/from electrode-attached Clostridia to control the metabolic shift in bacteria from acidogenesis to solventogenesis. The base line MFC (11.00 ± 4.69 g/L) fermentation experiment did produce higher acetone/ethanol than the baseline batch experiment MB (5.47 ± 4.48 g/L), indicating an improvement to solvent production in C. acetobutylicum (ATCC 824) in a MFC fermentation. In this study, MFC-1 demonstrated remarkable superiority over MB in terms of butyric acid production, yielding significantly higher concentrations while also improving acetone and ethanol production. However, the enhanced butyric acid production did not correspond to significantly increased butanol yields when compared to batch fermentation of chemically defined media. These findings highlight the potential of MFC-1 as an efficient approach for enhancing the fermentative production of valuable compounds, with a particular focus on butyric acid and acetone/ethanol. , Thesis (MSc) -- Faculty of Science, Biotechnology Innovation Centre, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Du Toit, Ryan Guillaume
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424643 , vital:72171
- Description: The production of the solvent compounds acetone, ethanol and butanol through fermentation of organic feedstocks using Clostridia species could be a promising route for biofuel production. However, the cost of raw materials, low yields and the complexity of anaerobic fermentation continue to hinder this means of generating these compounds. The research presented in this Thesis investigated low-cost interventions that could decrease the costs of production and to direct the synthesis of fuel compounds using microbial fuel cells. Low-cost anaerobic chambers were designed and constructed for the propagation and manipulation of Clostridium acetobutylicum, selected as a low-risk microbial catalyst. Fermentation was monitored using in situ pH measurements and a combination of turbidity measurements, nutrient assays (especially total carbohydrates) and HPLC-RI detection as a means of monitoring the consumption of nutrients (glucose), production of precursor compounds (butyric acid) and the formation of solvent molecules (acetone/ethanol and butanol) during fermentation by this organism. Brewer’s spent grains were tested as a sustainable and low-cost feedstock for solvent production, comparing the effects of sterilising before fermentation, or allowing resident microflora to remain during Clostridium-catalysed solvent production. Sterilised spent grains significantly improved the production of solvent molecules (e.g. 12.97 ± 0.38 g/L of butanol yielded, compared to 0.40 ± 0.33 g/L for defined media sampled during the solventogenic phase); compared to these, the use of non-sterilised brewer’s grain decreased both the reproducibility and yields of fermentation (8.66 ± 1.6 g/L of butanol). Microbial fuel cells were studied as a possible means of altering electron transfer to/from electrode-attached Clostridia to control the metabolic shift in bacteria from acidogenesis to solventogenesis. The base line MFC (11.00 ± 4.69 g/L) fermentation experiment did produce higher acetone/ethanol than the baseline batch experiment MB (5.47 ± 4.48 g/L), indicating an improvement to solvent production in C. acetobutylicum (ATCC 824) in a MFC fermentation. In this study, MFC-1 demonstrated remarkable superiority over MB in terms of butyric acid production, yielding significantly higher concentrations while also improving acetone and ethanol production. However, the enhanced butyric acid production did not correspond to significantly increased butanol yields when compared to batch fermentation of chemically defined media. These findings highlight the potential of MFC-1 as an efficient approach for enhancing the fermentative production of valuable compounds, with a particular focus on butyric acid and acetone/ethanol. , Thesis (MSc) -- Faculty of Science, Biotechnology Innovation Centre, 2023
- Full Text:
- Date Issued: 2023-10-13
Kant and the experience of skepticism: rranscendental arguments, skepticism, and a version of the problem of the justification of foundational assumptions
- Authors: Grecia, Hadley
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425078 , vital:72207
- Description: Immanuel Kant is a key thinker in the History of Western Philosophy whose ideas continue to fascinate contemporary English-speaking academic philosophers. One such idea is Kant's conception of transcendental arguments. Although these arguments do not originate in Kant's philosophy, Kant's conception of them occupies a special place in the English-speaking literature on the topic. A growing trend in this literature is to claim that Kant's transcendental arguments are unique because they aim to achieve an anti-skeptical end through deductive means. I call the basic assumption behind readings of transcendental arguments like these the deductive/anti-skeptical assumption. This assumption claims that deduction is the best means to achieve an anti-skeptical end. In this thesis, I argue that accepting this assumption is one way to misinterpret transcendental arguments because—even though it seems compelling at first blush—it must be false. The resultant twist is that transcendental arguments cannot be deductive, which, in turn, means that understanding that Kant's transcendental arguments are not deductive in nature is itself no small detail for understanding the version of Kant's 'not-deductive' solution to skepticism developed here. , Thesis (MA) -- Faculty of Humanities, Philosophy, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Grecia, Hadley
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425078 , vital:72207
- Description: Immanuel Kant is a key thinker in the History of Western Philosophy whose ideas continue to fascinate contemporary English-speaking academic philosophers. One such idea is Kant's conception of transcendental arguments. Although these arguments do not originate in Kant's philosophy, Kant's conception of them occupies a special place in the English-speaking literature on the topic. A growing trend in this literature is to claim that Kant's transcendental arguments are unique because they aim to achieve an anti-skeptical end through deductive means. I call the basic assumption behind readings of transcendental arguments like these the deductive/anti-skeptical assumption. This assumption claims that deduction is the best means to achieve an anti-skeptical end. In this thesis, I argue that accepting this assumption is one way to misinterpret transcendental arguments because—even though it seems compelling at first blush—it must be false. The resultant twist is that transcendental arguments cannot be deductive, which, in turn, means that understanding that Kant's transcendental arguments are not deductive in nature is itself no small detail for understanding the version of Kant's 'not-deductive' solution to skepticism developed here. , Thesis (MA) -- Faculty of Humanities, Philosophy, 2023
- Full Text:
- Date Issued: 2023-10-13
Leverage points for meaningful participatory governance: lessons from the Tsitsa River catchment, South Africa
- Authors: Fry, Anthony St Leger
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/431714 , vital:72798 , DOI 10.21504/10962/431714
- Description: South Africa underwent the renowned transition into a representative multiracial democracy in 1994. While there has been notable progress in many developmental aspects of South African society, many inherited dilemmas persist, and myriad novel ones are emerging. In land and water governance, the nascent institutions do not reflect the visions laid out in the pioneering and substantive legislation, policies, and guidelines generated in the post-1994 period. Unaddressed dilemmas include widespread failures in local water governance, persistent inequality of access to land and water, poor or non-existent service delivery in rural areas, underdeveloped institutions for integrated and inclusive water resource management, and pernicious divisions between institutions. Overcoming these challenges, which are embedded in complex social-ecological systems across South Africa, will require the collaborative effort of diverse actors from different levels and sectors of society. So how do we foster meaningful participation in ways that are not tyrannical, tokenistic, or manipulative? How do we build local institutions that make sense in the broader political system and in the lives of rural residents? How do we support institutions that meaningfully include diverse voices and enable tangible development outcomes? This thesis explores these questions as part of the Tsitsa Project, a transdisciplinary landscape management project working in the Tsitsa River Catchment (TsRC) in the rural parts of the Eastern Cape province of South Africa. Based on the valuable water resources, severe ecosystem degradation, overlapping traditional and democratic governance systems, and impoverished population, the TsRC is a worthwhile candidate for in-depth study paired with innovative efforts towards systemic development. The single place-based case study approach drew on systems thinking within an evolving transdisciplinary methodology. Qualitative data were collected through extended fieldwork and analysed through an adaptive and iterative approach. Governance mapping elucidated the multiple levels of governance, and a systemic analysis explored meaningful participation at the local level through causal diagramming and observation-based narratives. From the findings, a synthetic analysis identified high leverage points to enable participatory governance interventions to have more sustained impacts. Governance manifestations in the TsRC generally align with existing descriptions of the fractures and associated dilemmas across South Africa, with the added complexities of being a rural landscape in which democratic and traditional governance systems overlap and interact. Local participatory institutions need to endure the broader instability and dysfunction. Interventions must, therefore, be oriented towards trust building and shared understanding while using more practical interventions that provide tangible outcomes, enable in-practice capacity development, and support platforms for all actors to experience and practice meaningful participation together. This thesis aims to unearth the lessons that one small rural catchment might hold for the governance of complex, contested land and for water governance contexts more broadly. , Thesis (PhD) -- Faculty of Science, Institute for Water Research, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Fry, Anthony St Leger
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/431714 , vital:72798 , DOI 10.21504/10962/431714
- Description: South Africa underwent the renowned transition into a representative multiracial democracy in 1994. While there has been notable progress in many developmental aspects of South African society, many inherited dilemmas persist, and myriad novel ones are emerging. In land and water governance, the nascent institutions do not reflect the visions laid out in the pioneering and substantive legislation, policies, and guidelines generated in the post-1994 period. Unaddressed dilemmas include widespread failures in local water governance, persistent inequality of access to land and water, poor or non-existent service delivery in rural areas, underdeveloped institutions for integrated and inclusive water resource management, and pernicious divisions between institutions. Overcoming these challenges, which are embedded in complex social-ecological systems across South Africa, will require the collaborative effort of diverse actors from different levels and sectors of society. So how do we foster meaningful participation in ways that are not tyrannical, tokenistic, or manipulative? How do we build local institutions that make sense in the broader political system and in the lives of rural residents? How do we support institutions that meaningfully include diverse voices and enable tangible development outcomes? This thesis explores these questions as part of the Tsitsa Project, a transdisciplinary landscape management project working in the Tsitsa River Catchment (TsRC) in the rural parts of the Eastern Cape province of South Africa. Based on the valuable water resources, severe ecosystem degradation, overlapping traditional and democratic governance systems, and impoverished population, the TsRC is a worthwhile candidate for in-depth study paired with innovative efforts towards systemic development. The single place-based case study approach drew on systems thinking within an evolving transdisciplinary methodology. Qualitative data were collected through extended fieldwork and analysed through an adaptive and iterative approach. Governance mapping elucidated the multiple levels of governance, and a systemic analysis explored meaningful participation at the local level through causal diagramming and observation-based narratives. From the findings, a synthetic analysis identified high leverage points to enable participatory governance interventions to have more sustained impacts. Governance manifestations in the TsRC generally align with existing descriptions of the fractures and associated dilemmas across South Africa, with the added complexities of being a rural landscape in which democratic and traditional governance systems overlap and interact. Local participatory institutions need to endure the broader instability and dysfunction. Interventions must, therefore, be oriented towards trust building and shared understanding while using more practical interventions that provide tangible outcomes, enable in-practice capacity development, and support platforms for all actors to experience and practice meaningful participation together. This thesis aims to unearth the lessons that one small rural catchment might hold for the governance of complex, contested land and for water governance contexts more broadly. , Thesis (PhD) -- Faculty of Science, Institute for Water Research, 2023
- Full Text:
- Date Issued: 2023-10-13
Personnages dans l’espace, Personnages comme espace: une analyse du conte « Barbe Bleue » par Charles Perrault et les révisions de Tahar Ben Jelloun et d’Amélie Nothomb
- Authors: Jimu, Kundai Michelle
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: French
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424943 , vital:72195
- Description: Dans un couple, la négociation de l’espace domestique est contesté. Dans le conte « La Barbe Bleue » (1697) de Charles Perrault, cette négociation de l’espace est particulièrement dangereuse. Le mari a un espace privé à lui, interdite à sa femme, dans lequel il cache un secret sinistre : il a tué toutes les épouses précédentes. L’existence de cette pièce menace l’équilibre du foyer, mettant en question le droit à un espace privé, et révélant le danger de garder un secret quand on vit en couple. Quand l’épouse franchit le seuil de la pièce interdite, son mari se met en colère et s’apprête à la tuer. Il s’ensuit une lutte acharnée entre homme et femme, devenus adversaires. Puisque la chambre interdite joue un rôle capital dans ce récit, cela suggère que les éléments spatiaux jouent un rôle significatif au sein du couple. Alors, on vise à analyser le cadre domestique et son rôle dans le rapport entre les personnages. Avant leur mariage, l’épouse avait déjà une idée que Barbe Bleue n’était pas honorable, ce qui remet en question sa décision d’épouser cet homme. Au même temps, on se demande pourquoi l’époux aurait tué toutes les épouses précédentes. Cela incite le lecteur à chercher à mieux comprendre les personnages. A cette fin, on vise à considérer les personnages comme des espaces, eux aussi, ce qui permettra une analyse approfondie de leur caractère et de leurs rapports personnels. Nous ferons la comparaison du conte perraultien avec les versions contemporaines de notre époque de Tahar Ben Jelloun et d’Amélie Nothomb. Dans la version jellounienne, l’intrigue se déroule dans un cadre musulman et maghrébin, tandis que le récit nothombien se situe à Paris. Ces ouvrages présentent donc des perspectives neuves sur Barbe Bleue et sa dernière épouse, et sur le cadre dans lequel ils se trouvent. , For a couple, negotiating the spatial dynamics of their home can be a challenging feat. In the story of “Bluebeard” (1697) by Charles Perrault, this negotiation is presented in an even more grim light. The husband sets aside a private room for himself, off-limits to his wife, in which he conceals a deadly secret, that he has murdered his previous wives. The very existence of this forbidden chamber threatens the stability of the household and raises the question about whether secret unshared spaces between partners are tenable, and indeed whether spouses have the right to keep secrets. When the wife enters this forbidden room and discovers the corpses of his previous wives she provokes the anger of her husband, who then attempts to kill her as punishment. A fierce struggle ensues between husband and wife, who have now become adversaries. Because the forbidden chamber plays a key role in this story, this tells us that space is very important to the relationship between the couple. Thus, we intend to explore the domestic sphere and its role in the relationship between the characters. Prior to their marriage, the wife already has an indication as to her husband’s dubious character, which calls into question her decision to marry him. We also wonder why Bluebeard might have murdered his previous wives. To understand them better, the characters will be considered as spaces, an approach which has the potential to offer a deeper and more holistic analysis of their characters and their personal relationships. We will be comparing Perrault’s tale to two revisions by Tahar Ben Jelloun and Amélie Nothomb, which place the story into different contexts: the Islamic world and modern-day Paris respectively. These two revisions provide interesting and new perspectives on the couple in the domestic space and the ways in which the characters are represented. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Jimu, Kundai Michelle
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: French
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424943 , vital:72195
- Description: Dans un couple, la négociation de l’espace domestique est contesté. Dans le conte « La Barbe Bleue » (1697) de Charles Perrault, cette négociation de l’espace est particulièrement dangereuse. Le mari a un espace privé à lui, interdite à sa femme, dans lequel il cache un secret sinistre : il a tué toutes les épouses précédentes. L’existence de cette pièce menace l’équilibre du foyer, mettant en question le droit à un espace privé, et révélant le danger de garder un secret quand on vit en couple. Quand l’épouse franchit le seuil de la pièce interdite, son mari se met en colère et s’apprête à la tuer. Il s’ensuit une lutte acharnée entre homme et femme, devenus adversaires. Puisque la chambre interdite joue un rôle capital dans ce récit, cela suggère que les éléments spatiaux jouent un rôle significatif au sein du couple. Alors, on vise à analyser le cadre domestique et son rôle dans le rapport entre les personnages. Avant leur mariage, l’épouse avait déjà une idée que Barbe Bleue n’était pas honorable, ce qui remet en question sa décision d’épouser cet homme. Au même temps, on se demande pourquoi l’époux aurait tué toutes les épouses précédentes. Cela incite le lecteur à chercher à mieux comprendre les personnages. A cette fin, on vise à considérer les personnages comme des espaces, eux aussi, ce qui permettra une analyse approfondie de leur caractère et de leurs rapports personnels. Nous ferons la comparaison du conte perraultien avec les versions contemporaines de notre époque de Tahar Ben Jelloun et d’Amélie Nothomb. Dans la version jellounienne, l’intrigue se déroule dans un cadre musulman et maghrébin, tandis que le récit nothombien se situe à Paris. Ces ouvrages présentent donc des perspectives neuves sur Barbe Bleue et sa dernière épouse, et sur le cadre dans lequel ils se trouvent. , For a couple, negotiating the spatial dynamics of their home can be a challenging feat. In the story of “Bluebeard” (1697) by Charles Perrault, this negotiation is presented in an even more grim light. The husband sets aside a private room for himself, off-limits to his wife, in which he conceals a deadly secret, that he has murdered his previous wives. The very existence of this forbidden chamber threatens the stability of the household and raises the question about whether secret unshared spaces between partners are tenable, and indeed whether spouses have the right to keep secrets. When the wife enters this forbidden room and discovers the corpses of his previous wives she provokes the anger of her husband, who then attempts to kill her as punishment. A fierce struggle ensues between husband and wife, who have now become adversaries. Because the forbidden chamber plays a key role in this story, this tells us that space is very important to the relationship between the couple. Thus, we intend to explore the domestic sphere and its role in the relationship between the characters. Prior to their marriage, the wife already has an indication as to her husband’s dubious character, which calls into question her decision to marry him. We also wonder why Bluebeard might have murdered his previous wives. To understand them better, the characters will be considered as spaces, an approach which has the potential to offer a deeper and more holistic analysis of their characters and their personal relationships. We will be comparing Perrault’s tale to two revisions by Tahar Ben Jelloun and Amélie Nothomb, which place the story into different contexts: the Islamic world and modern-day Paris respectively. These two revisions provide interesting and new perspectives on the couple in the domestic space and the ways in which the characters are represented. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2023
- Full Text:
- Date Issued: 2023-10-13
Phylogeography of two small owl species in South Africa: population genetics and phenotypic variation in the African Barred Owlet (Glaucidium capense) and the African Scops Owl (Otus senegalensis)
- Authors: Balmer, Jonathan Peter
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424369 , vital:72147
- Description: Embargoed. Expected release date in 2025. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Balmer, Jonathan Peter
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424369 , vital:72147
- Description: Embargoed. Expected release date in 2025. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
Porphyrinoid dyes for photodynamic anticancer and antimicrobial therapy treatments
- Authors: Soy, Rodah Cheruto
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432252 , vital:72855 , DOI 10.21504/10962/432252
- Description: The search for alternative therapies and non-toxic photosensitizer drugs that can efficiently generate cytotoxic reactive oxygen species for biomedical applications, such as in alternative photodynamic therapy (PDT) for cancer treatment and photodynamic antimicrobial chemotherapy (PACT) for drug-resistant bacteria treatment is on the rise. Nevertheless, the lack of photosensitizer dyes that absorb light strongly within the therapeutic window (620−850 nm) that can locally target the tumor and bacterial cells and generate singlet oxygen efficiently are some of the main challenges in PDT and PACT treatment. This study sought to address the challenges that impede PDT and PACT from realizing their full potential by synthesizing a series of meso-aryltetrapyrrolic photosensitizer dyes that absorb light within the therapeutic window. These include meso-tetraarylporphyrin (Por), A3-type meso-triarylcorrole (Cor), meso-tetraarylchlorin (Chl), and N-confused meso-tetraarylporphyrin (NCP) dyes with 4-thiomethylphenyl (1), thien-3-yl (2), thien-2-yl (3), 5-bromo-thien-2-yl (4), 4-methoxyphenyl (5), 3-methoxyphenyl (6), 4-hydroxyphenyl (7) and 4-hydroxy-3-methoxyphenyl (8) meso-aryl rings. Por, Cor, Chl and NCP dyes and and their Ga(III), P(V), In(III) and/or Sn(IV) complexes with 1-8, 1-4, 5-8 and 5 meso-aryl rings were studied, along with two A2B-type Ga(III) meso-triarylcorroles with pentafluorophenyl rings at the A2 positions and 3,6-di-t-butyl-9H-carbazole (9) or N-butyl-4-carbazole (10) rings at the B position that were prepared in the laboratory of Prof. Xu Liang of Jiangsu University in the People’s Republic of China. The carbazole nitrogen of 10-GaCor was quaternized at Rhodes University with ethyl iodide to form a cationic species (10-GaCor-Q) for PDT and PACT activity studies. The structures of the synthesized dyes were confirmed using UV-visible absorption and 1H NMR spectroscopy, and MALDI-TOF-mass spectrometry. 1-4-InPor In(III) porphyrins, 1-4-PVCor, 1-4-GaCor A3 PV and GaIII corrole dyes were also conjugated to gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs) via sulfur-gold and sulfur-silver affinities. The successful conjugation of the dyes onto the nanoparticles to form dye-AuNP or dye-AgNP nanoassemblies was confirmed using transmission electron microscopy (TEM), energy dispersive X-ray (EDX) spectroscopy, X-ray powered diffraction (XRD), and (X-ray photon spectroscopy) XPS. The photophysicochemical, photostability, and lipophilicity properties of the dyes and their PDT and PACT activities were investigated, and the structure-property relationships were analyzed. This was accomplished by analyzing the changes in the properties of the dyes due to the meso-aryl substituents, central ions, molecular symmetry, and heavy atom effects. Time-dependent-density functional theory (TD-DFT) calculations were also used to further probe the electronic and optical spectroscopic properties of the dyes. The analysis of the photophysicochemical, photostability, and lipophilicity data for the synthesized dyes demonstrated that there are inherent structure-property relationships for the dyes studied. The TD-DFT calculations also assisted in rationalizing the observed optical spectroscopic data for the dyes. The introduction of different meso-aryl substituents resulted in minor absorption spectral changes on the parent structures of the dyes due to their inductive and mesomeric effects, while the insertion of Ga(III), In(III), and Sn(IV) electropositive metal centers resulted in marked red shifts of the B bands due to favorable interactions with the porphyrin or porphyrinoid ligand core. The lower symmetries of the corrole, chlorin, and N-confused porphyrin dyes resulted in enhanced absorption properties within the therapeutic window relative to porphyrins. The heavy atom effect from the Ga(III), In(III), and Sn(IV) central ions, the meso-aryl groups, and the external heavy atom effect from the AuNPs and AgNPs significantly reduced the fluorescence quantum yield values of the dyes resulting in high singlet oxygen quantum yields. The dye complexes also exhibited properly balanced lipophilic properties and high photostabilities. The P(V) ion of the A3 PV corrole dyes reduced the aggregation effects, enhanced cellular uptake, and lowered the lipophilicity values relative to the A3 GaIII corrole dyes. The porphyrin and porphyrinoid complexes studied exhibited relatively low in vitro dark cytotoxicity toward MCF-7 cancer cells, which is enhanced for AuNP nanoconjugates of 1-InPor, 1-3-PVCor, and 1-3-GaCor. The dyes also have low in vitro dark cytotoxicity toward planktonic and biofilm cells of S. aureus and E. coli. The complexes also exhibited favorable PDT and PACT activities toward MCF-7 cancer cells, and planktonic and biofilm S. aureus and E. coli bacteria due to their high singlet oxygen quantum yields. AuNP and AgNP nanoconjugates of 1-4-InPor, 1-4-PVCor, and 1-4-GaCor exhibited enhanced PDT and PACT activities due to the favorable synergistic effects of nanoparticles. The PDT and PACT activities of A3 PV corrole dyes and the nanoconjugates of 1-4-PVCor are slightly higher than those of A3-type GaIII corroles and their nanoconjugates due to decreased aggregation effects and enhanced PS drug uptake. The cationic 10-GaCor-Q species also exhibit favorable PDT and PACT activities in contrast to the neutral 9-10-GaCor dyes due to enhanced PS drug penetration into the tumor or bacteria cells. The complexes also exhibited high Log10 reduction values for planktonic S. aureus suggesting that the dyes are highly efficient PS dyes. The activities of the complexes toward planktonic E. coli bacteria are moderate except for 10-GaCor-Q, 2-4-PVCor-AgNPs, and 5-8-SnChl chlorins exhibiting relatively favorable activity with > 3 Log10 CFU.mL−1 values. The dyes also exhibit moderate activities toward the S. aureus and E. coli biofilm cells, which are lower than for the planktonic cells, as shown by their lower Log10 reduction values. The data demonstrate that the low symmetry corrole, chlorin, and N-confused porphyrin complexes that absorb light strongly within the therapeutic window have significantly enhanced PDT and PACT activities relative to their porphyrin analogs. , Thesis (PhD) -- Faculty of Science, Chemistry, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Soy, Rodah Cheruto
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432252 , vital:72855 , DOI 10.21504/10962/432252
- Description: The search for alternative therapies and non-toxic photosensitizer drugs that can efficiently generate cytotoxic reactive oxygen species for biomedical applications, such as in alternative photodynamic therapy (PDT) for cancer treatment and photodynamic antimicrobial chemotherapy (PACT) for drug-resistant bacteria treatment is on the rise. Nevertheless, the lack of photosensitizer dyes that absorb light strongly within the therapeutic window (620−850 nm) that can locally target the tumor and bacterial cells and generate singlet oxygen efficiently are some of the main challenges in PDT and PACT treatment. This study sought to address the challenges that impede PDT and PACT from realizing their full potential by synthesizing a series of meso-aryltetrapyrrolic photosensitizer dyes that absorb light within the therapeutic window. These include meso-tetraarylporphyrin (Por), A3-type meso-triarylcorrole (Cor), meso-tetraarylchlorin (Chl), and N-confused meso-tetraarylporphyrin (NCP) dyes with 4-thiomethylphenyl (1), thien-3-yl (2), thien-2-yl (3), 5-bromo-thien-2-yl (4), 4-methoxyphenyl (5), 3-methoxyphenyl (6), 4-hydroxyphenyl (7) and 4-hydroxy-3-methoxyphenyl (8) meso-aryl rings. Por, Cor, Chl and NCP dyes and and their Ga(III), P(V), In(III) and/or Sn(IV) complexes with 1-8, 1-4, 5-8 and 5 meso-aryl rings were studied, along with two A2B-type Ga(III) meso-triarylcorroles with pentafluorophenyl rings at the A2 positions and 3,6-di-t-butyl-9H-carbazole (9) or N-butyl-4-carbazole (10) rings at the B position that were prepared in the laboratory of Prof. Xu Liang of Jiangsu University in the People’s Republic of China. The carbazole nitrogen of 10-GaCor was quaternized at Rhodes University with ethyl iodide to form a cationic species (10-GaCor-Q) for PDT and PACT activity studies. The structures of the synthesized dyes were confirmed using UV-visible absorption and 1H NMR spectroscopy, and MALDI-TOF-mass spectrometry. 1-4-InPor In(III) porphyrins, 1-4-PVCor, 1-4-GaCor A3 PV and GaIII corrole dyes were also conjugated to gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs) via sulfur-gold and sulfur-silver affinities. The successful conjugation of the dyes onto the nanoparticles to form dye-AuNP or dye-AgNP nanoassemblies was confirmed using transmission electron microscopy (TEM), energy dispersive X-ray (EDX) spectroscopy, X-ray powered diffraction (XRD), and (X-ray photon spectroscopy) XPS. The photophysicochemical, photostability, and lipophilicity properties of the dyes and their PDT and PACT activities were investigated, and the structure-property relationships were analyzed. This was accomplished by analyzing the changes in the properties of the dyes due to the meso-aryl substituents, central ions, molecular symmetry, and heavy atom effects. Time-dependent-density functional theory (TD-DFT) calculations were also used to further probe the electronic and optical spectroscopic properties of the dyes. The analysis of the photophysicochemical, photostability, and lipophilicity data for the synthesized dyes demonstrated that there are inherent structure-property relationships for the dyes studied. The TD-DFT calculations also assisted in rationalizing the observed optical spectroscopic data for the dyes. The introduction of different meso-aryl substituents resulted in minor absorption spectral changes on the parent structures of the dyes due to their inductive and mesomeric effects, while the insertion of Ga(III), In(III), and Sn(IV) electropositive metal centers resulted in marked red shifts of the B bands due to favorable interactions with the porphyrin or porphyrinoid ligand core. The lower symmetries of the corrole, chlorin, and N-confused porphyrin dyes resulted in enhanced absorption properties within the therapeutic window relative to porphyrins. The heavy atom effect from the Ga(III), In(III), and Sn(IV) central ions, the meso-aryl groups, and the external heavy atom effect from the AuNPs and AgNPs significantly reduced the fluorescence quantum yield values of the dyes resulting in high singlet oxygen quantum yields. The dye complexes also exhibited properly balanced lipophilic properties and high photostabilities. The P(V) ion of the A3 PV corrole dyes reduced the aggregation effects, enhanced cellular uptake, and lowered the lipophilicity values relative to the A3 GaIII corrole dyes. The porphyrin and porphyrinoid complexes studied exhibited relatively low in vitro dark cytotoxicity toward MCF-7 cancer cells, which is enhanced for AuNP nanoconjugates of 1-InPor, 1-3-PVCor, and 1-3-GaCor. The dyes also have low in vitro dark cytotoxicity toward planktonic and biofilm cells of S. aureus and E. coli. The complexes also exhibited favorable PDT and PACT activities toward MCF-7 cancer cells, and planktonic and biofilm S. aureus and E. coli bacteria due to their high singlet oxygen quantum yields. AuNP and AgNP nanoconjugates of 1-4-InPor, 1-4-PVCor, and 1-4-GaCor exhibited enhanced PDT and PACT activities due to the favorable synergistic effects of nanoparticles. The PDT and PACT activities of A3 PV corrole dyes and the nanoconjugates of 1-4-PVCor are slightly higher than those of A3-type GaIII corroles and their nanoconjugates due to decreased aggregation effects and enhanced PS drug uptake. The cationic 10-GaCor-Q species also exhibit favorable PDT and PACT activities in contrast to the neutral 9-10-GaCor dyes due to enhanced PS drug penetration into the tumor or bacteria cells. The complexes also exhibited high Log10 reduction values for planktonic S. aureus suggesting that the dyes are highly efficient PS dyes. The activities of the complexes toward planktonic E. coli bacteria are moderate except for 10-GaCor-Q, 2-4-PVCor-AgNPs, and 5-8-SnChl chlorins exhibiting relatively favorable activity with > 3 Log10 CFU.mL−1 values. The dyes also exhibit moderate activities toward the S. aureus and E. coli biofilm cells, which are lower than for the planktonic cells, as shown by their lower Log10 reduction values. The data demonstrate that the low symmetry corrole, chlorin, and N-confused porphyrin complexes that absorb light strongly within the therapeutic window have significantly enhanced PDT and PACT activities relative to their porphyrin analogs. , Thesis (PhD) -- Faculty of Science, Chemistry, 2023
- Full Text:
- Date Issued: 2023-10-13
Relating vegetation distribution to cycles of erosion and deposition in the Kromme River wetlands
- Authors: Jarvis, Samuel Cameron
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424582 , vital:72166
- Description: The role of geomorphic disturbance has been increasingly recognized as fundamental in the creation and functioning of wetlands. This is true of the Kromme River wetland which has been formed through repeated cycles of erosion and deposition. However, the response – and influence – of wetland plants to these sorts of disturbance has not been investigated. This study sought to fill this knowledge gap by classifying vegetation communities over a range of hydrological and geomorphic disturbance regimes that have happened over the last few decades, and relating those vegetation communities to environmental factors. The study identified seven vegetation communities based on their species composition and abundance, which were related to geomorphic disturbance events. A conceptual model that accounts for vegetation distribution in the Kromme wetland was developed. Soil saturation was the most important factor explaining vegetation community distribution, which, in turn, is influenced by cycles of erosion and deposition. Following an erosional event on the valley floor, Prionium serratum dominated wetland is converted to a number of other vegetation communities. On the floodplain surface adjacent to the eroded gully, the Prionium serratum dominated wetland is transformed over time to Cynodon dactylon and Sporobolus fimbriatus communities. Prionium serratum clumps immediately adjacent to the recently incised gullies are able to persist, having sufficient access to water. Within the newly formed gullies, Juncus lomatophyllus colonizes the gully beds flooded to a shallow depth, Miscanthus capensis colonizes the gully bars and Setaria incrassata colonizes the exposed gully banks. Localised depositional features close to the thalweg in the gully are colonized by Prionium serratum seedlings and vegetative propagules. These plants represent the regenerating phase of Prionium serratum wetland, which also colonizes depositional floodouts downstream of the newly-formed gully. The Stenotaphrum secundatum community dominates drier, more elevated areas of the floodout. Over time, as the gully fills, Prionium serratum expands beyond the gully onto the valley floor, to replace the floodplain communities Cynodon dactylon and Sporobolus fimbriatus. Over time, Prionium serratum is thought to colonize the valley floor as the gully fills, stabilising it and promoting diffuse flow. Many restoration efforts in damaged palmiet wetlands have been focused on the preservation of intact palmiet communities upstream of erosional headcuts, with limited understanding of vegetation dynamics associated with the cut-and-fill cycles that naturally occur in these wetlands. Understanding the regeneration of Prionium serratum following erosional events is thus important for wetland restoration, as it should focus more attention on promoting palmiet restoration on depositional floodouts downstream of eroded gullies. A secondary aim of this study was to explore the possibility of mapping palmiet communities in Kromme River wetland using remote sensing techniques. Using a combination of ground-truthed data from this and previous studies in the Kromme River wetland, together with raster layers derived from a LiDAR survey, an overlay analysis was developed to effectively map the distribution of the Prionium serratum dominated community. The overlay was created using a machine learning library in RStudios known as Rpart. The results found that the model were 91% effective in classifying the distribution of the Prionium serratum community. A secondary finding was that the inclusion of a Relative Elevation Model in the overlay analysis allowed for the identification of Prionium serratum communities vulnerable to degradation following previous geomorphic disturbance events and those Prionium serratum communities that are likely to persist following a geomorphic disturbance event. , Thesis (MSc) -- Faculty of Science, Geography, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Jarvis, Samuel Cameron
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424582 , vital:72166
- Description: The role of geomorphic disturbance has been increasingly recognized as fundamental in the creation and functioning of wetlands. This is true of the Kromme River wetland which has been formed through repeated cycles of erosion and deposition. However, the response – and influence – of wetland plants to these sorts of disturbance has not been investigated. This study sought to fill this knowledge gap by classifying vegetation communities over a range of hydrological and geomorphic disturbance regimes that have happened over the last few decades, and relating those vegetation communities to environmental factors. The study identified seven vegetation communities based on their species composition and abundance, which were related to geomorphic disturbance events. A conceptual model that accounts for vegetation distribution in the Kromme wetland was developed. Soil saturation was the most important factor explaining vegetation community distribution, which, in turn, is influenced by cycles of erosion and deposition. Following an erosional event on the valley floor, Prionium serratum dominated wetland is converted to a number of other vegetation communities. On the floodplain surface adjacent to the eroded gully, the Prionium serratum dominated wetland is transformed over time to Cynodon dactylon and Sporobolus fimbriatus communities. Prionium serratum clumps immediately adjacent to the recently incised gullies are able to persist, having sufficient access to water. Within the newly formed gullies, Juncus lomatophyllus colonizes the gully beds flooded to a shallow depth, Miscanthus capensis colonizes the gully bars and Setaria incrassata colonizes the exposed gully banks. Localised depositional features close to the thalweg in the gully are colonized by Prionium serratum seedlings and vegetative propagules. These plants represent the regenerating phase of Prionium serratum wetland, which also colonizes depositional floodouts downstream of the newly-formed gully. The Stenotaphrum secundatum community dominates drier, more elevated areas of the floodout. Over time, as the gully fills, Prionium serratum expands beyond the gully onto the valley floor, to replace the floodplain communities Cynodon dactylon and Sporobolus fimbriatus. Over time, Prionium serratum is thought to colonize the valley floor as the gully fills, stabilising it and promoting diffuse flow. Many restoration efforts in damaged palmiet wetlands have been focused on the preservation of intact palmiet communities upstream of erosional headcuts, with limited understanding of vegetation dynamics associated with the cut-and-fill cycles that naturally occur in these wetlands. Understanding the regeneration of Prionium serratum following erosional events is thus important for wetland restoration, as it should focus more attention on promoting palmiet restoration on depositional floodouts downstream of eroded gullies. A secondary aim of this study was to explore the possibility of mapping palmiet communities in Kromme River wetland using remote sensing techniques. Using a combination of ground-truthed data from this and previous studies in the Kromme River wetland, together with raster layers derived from a LiDAR survey, an overlay analysis was developed to effectively map the distribution of the Prionium serratum dominated community. The overlay was created using a machine learning library in RStudios known as Rpart. The results found that the model were 91% effective in classifying the distribution of the Prionium serratum community. A secondary finding was that the inclusion of a Relative Elevation Model in the overlay analysis allowed for the identification of Prionium serratum communities vulnerable to degradation following previous geomorphic disturbance events and those Prionium serratum communities that are likely to persist following a geomorphic disturbance event. , Thesis (MSc) -- Faculty of Science, Geography, 2023
- Full Text:
- Date Issued: 2023-10-13
Spatial analysis of littoral and demersal fish assemblages within the Knysna Estuary system
- Authors: Meiklejohn, Andrew Keith
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424334 , vital:72144
- Description: The Knysna Estuary is a unique system as it is the only “estuarine bay” system in the warm-temperate region of South Africa and is the largest estuary system on the southern coastline of South Africa. The Knysna Estuary has been identified as the estuary with the highest conversation priority in South Africa. The volume of research undertaken on the Knysna Estuary has led to it being rated “excellent” in terms of research productivity. However, despite this, surprisingly little work has been undertaken and published around the dynamics of fish assemblages occurring in the system, with little to no research assessing the demersal fish assemblage. The last widespread fish sampling effort that has been published was conducted in 1994, highlighting the need for an updated fish assessment with a focused sampling effort targeting both the littoral and demersal fish populations. The identification of key habitats for estuarine fish assemblages is essential for addressing estuarine conservation needs. Despite the importance of spatial data in addressing conservation planning, few estuarine studies have used spatial analyses in Geographic Information Systems (GIS) to identify conservation priority areas. Such information is critical for effective estuarine management plans. The aim of this project was to identify juvenile fish density hotspots to inform future systematic conservation planning. This study made use of two methods of sampling, seine netting to target the littoral fish assemblage and beam trawling to target demersal fish species. Two dedicated sampling trips for each sampling method were undertaken in June 2021 and March 2022 for Seine net sampling and November 2021 and March 2022 for Beam trawl sampling. Fish were identified to species level, measured (mm TL) and categorised into life history stages (i.e. settlement stage, juvenile and adult) and thereafter assigned into their various estuarine association guilds. A total of 47 species were recorded, with 42 species were caught in the seine net sampling and 24 species in the beam trawl sampling. The results from this study showed the vast extent of marine dominance in the Knysna Estuary, with marine estuarine-opportunist (MEO) species dominating catches (richness) from both sampling methods. The spatial analysis highlighted the importance of the lower “marine bay” region of the system, with the majority of estuarine guilds showing a high abundance in this region. Key fishery species and dominant fish species were identified during this study, the dominant species during the sampling effort were identified as ecologically important fish species and were dominated by adult specimens. The key fishery species sampled during this study were dominated by juvenile specimens. This highlights the role of the Knysna Estuary as a nursery area for juvenile fishery species and the contribution of the estuary to the estuarine and adjacent coastal fisheries. Key hotspots were identified for fishery species, these being the “Ashmead Channel” in the marine bay region and the “Belvidere” section of the lagoon region. Ashmead channel is sheltered backwater area while the Belvidere section is some distance from the main river channel, reducing the anthropogenic impact on these areas. The low anthropogenic utilization of these areas along with weaker water current in these regions was linked to the usage of these region by key fishery species. These areas were highlighted as important conservation hotspots with both currently not adequately protected under the current habitat sensitivity management model. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Meiklejohn, Andrew Keith
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424334 , vital:72144
- Description: The Knysna Estuary is a unique system as it is the only “estuarine bay” system in the warm-temperate region of South Africa and is the largest estuary system on the southern coastline of South Africa. The Knysna Estuary has been identified as the estuary with the highest conversation priority in South Africa. The volume of research undertaken on the Knysna Estuary has led to it being rated “excellent” in terms of research productivity. However, despite this, surprisingly little work has been undertaken and published around the dynamics of fish assemblages occurring in the system, with little to no research assessing the demersal fish assemblage. The last widespread fish sampling effort that has been published was conducted in 1994, highlighting the need for an updated fish assessment with a focused sampling effort targeting both the littoral and demersal fish populations. The identification of key habitats for estuarine fish assemblages is essential for addressing estuarine conservation needs. Despite the importance of spatial data in addressing conservation planning, few estuarine studies have used spatial analyses in Geographic Information Systems (GIS) to identify conservation priority areas. Such information is critical for effective estuarine management plans. The aim of this project was to identify juvenile fish density hotspots to inform future systematic conservation planning. This study made use of two methods of sampling, seine netting to target the littoral fish assemblage and beam trawling to target demersal fish species. Two dedicated sampling trips for each sampling method were undertaken in June 2021 and March 2022 for Seine net sampling and November 2021 and March 2022 for Beam trawl sampling. Fish were identified to species level, measured (mm TL) and categorised into life history stages (i.e. settlement stage, juvenile and adult) and thereafter assigned into their various estuarine association guilds. A total of 47 species were recorded, with 42 species were caught in the seine net sampling and 24 species in the beam trawl sampling. The results from this study showed the vast extent of marine dominance in the Knysna Estuary, with marine estuarine-opportunist (MEO) species dominating catches (richness) from both sampling methods. The spatial analysis highlighted the importance of the lower “marine bay” region of the system, with the majority of estuarine guilds showing a high abundance in this region. Key fishery species and dominant fish species were identified during this study, the dominant species during the sampling effort were identified as ecologically important fish species and were dominated by adult specimens. The key fishery species sampled during this study were dominated by juvenile specimens. This highlights the role of the Knysna Estuary as a nursery area for juvenile fishery species and the contribution of the estuary to the estuarine and adjacent coastal fisheries. Key hotspots were identified for fishery species, these being the “Ashmead Channel” in the marine bay region and the “Belvidere” section of the lagoon region. Ashmead channel is sheltered backwater area while the Belvidere section is some distance from the main river channel, reducing the anthropogenic impact on these areas. The low anthropogenic utilization of these areas along with weaker water current in these regions was linked to the usage of these region by key fishery species. These areas were highlighted as important conservation hotspots with both currently not adequately protected under the current habitat sensitivity management model. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2023
- Full Text:
- Date Issued: 2023-10-13
Stimulating continuous professional development and teacher leadership in a rural Namibian school: a participatory action research
- Authors: Mario, Kangende Mebin
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424075 , vital:72121
- Description: Namibia values democratic and quality education. One way to improve quality education is by allowing teachers autonomy and offering continuous professional development (CPD) to teachers. Historically, the CPD programmes on offer in Namibia were centralised and generic, using a ‘one-size-fits-all’ approach offered as mini workshops to train teachers. In 2012, a decentralised method of school-based CPD program was initiated in schools, to give opportunities to schools to identify, plan, implement and evaluate their own professional needs. However, a recent study indicated that these initiatives have failed due to poor leadership, a lack of training and support as well as limited knowledge of principals in running CPD initiatives. Against this backdrop, my study aimed at engaging in a participatory action research process with teachers and SMT members in a rural combined school in the Kavango West region to stimulate the failed school-based CPD program and develop teacher leadership. My study therefore aligned with the international recommendations that school-based CPD be built around the notions of distributed leadership and teacher leadership (Smulyan, 2016; Hunzicker, 2018). The three-step model of change and action research developed by Kurt Lewin served as the underpinning theory for this study. The study was situated within a critical paradigm and driven by the question: “Does the involvement in participatory action research process stimulate a school-based CPD programme and develop teacher leadership?” The study involved two phases. The contextual profiling stage generated data through the analysis of documents, focus group interviews, and observation. Phase 2 engaged the participant in participatory action research to stimulate school-based CPD and develop teacher leadership. Thematic analysis supported by both inductive and deductive methods was used to analyse the data. The findings from phase one indicated that CPD was interpreted differently by the participants and confirmed that there was no CPD program in the school. Using Grant's (2017) model of teacher leadership, the findings further revealed that although teacher leadership was practised in all four zones, it was strongest in the classroom and initiated through delegated practices. Using Angelle and Dehart (2010), constraining forces included negative teachers’ attitudes, limited knowledge, skills, and confidence as well as a school culture of distrust. Phase 2 revealed that participatory action research can be a useful stimulus for school-based CPD. A tangible output from the PAR sessions was a template for the internal policy for school-based continuous teacher development. In addition, the findings from the sessions indicated the significance of supportive leadership to ensure the efficacy of school-based CPD and teacher leadership. , Thesis (MEd) -- Faculty of Education, Primary and Early Childhood Education, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mario, Kangende Mebin
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424075 , vital:72121
- Description: Namibia values democratic and quality education. One way to improve quality education is by allowing teachers autonomy and offering continuous professional development (CPD) to teachers. Historically, the CPD programmes on offer in Namibia were centralised and generic, using a ‘one-size-fits-all’ approach offered as mini workshops to train teachers. In 2012, a decentralised method of school-based CPD program was initiated in schools, to give opportunities to schools to identify, plan, implement and evaluate their own professional needs. However, a recent study indicated that these initiatives have failed due to poor leadership, a lack of training and support as well as limited knowledge of principals in running CPD initiatives. Against this backdrop, my study aimed at engaging in a participatory action research process with teachers and SMT members in a rural combined school in the Kavango West region to stimulate the failed school-based CPD program and develop teacher leadership. My study therefore aligned with the international recommendations that school-based CPD be built around the notions of distributed leadership and teacher leadership (Smulyan, 2016; Hunzicker, 2018). The three-step model of change and action research developed by Kurt Lewin served as the underpinning theory for this study. The study was situated within a critical paradigm and driven by the question: “Does the involvement in participatory action research process stimulate a school-based CPD programme and develop teacher leadership?” The study involved two phases. The contextual profiling stage generated data through the analysis of documents, focus group interviews, and observation. Phase 2 engaged the participant in participatory action research to stimulate school-based CPD and develop teacher leadership. Thematic analysis supported by both inductive and deductive methods was used to analyse the data. The findings from phase one indicated that CPD was interpreted differently by the participants and confirmed that there was no CPD program in the school. Using Grant's (2017) model of teacher leadership, the findings further revealed that although teacher leadership was practised in all four zones, it was strongest in the classroom and initiated through delegated practices. Using Angelle and Dehart (2010), constraining forces included negative teachers’ attitudes, limited knowledge, skills, and confidence as well as a school culture of distrust. Phase 2 revealed that participatory action research can be a useful stimulus for school-based CPD. A tangible output from the PAR sessions was a template for the internal policy for school-based continuous teacher development. In addition, the findings from the sessions indicated the significance of supportive leadership to ensure the efficacy of school-based CPD and teacher leadership. , Thesis (MEd) -- Faculty of Education, Primary and Early Childhood Education, 2023
- Full Text:
- Date Issued: 2023-10-13
The activity and foraging patterns of the western rock elephant shrew (Elephantulus rupestris)
- Authors: Jackson, Emily Anne
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424402 , vital:72150
- Description: The increase, and prolonged periods, of high ambient temperatures are cause for concern for small mammals living in arid areas of Southern Africa. In this study, I aimed to determine the effect of high environmental temperatures on the activity, body temperature maintenance and foraging behaviour in a population of Western rock elephant shrew, Elephantulus rupestris, in the Eastern Cape, South Africa. I found that E. rupestris maintained stable body temperatures (Tb = 37.31 °C ± 0.64) over a range of environmental temperatures (Tair = 5° to 33.9 °C), indicating their ability to remain normothermic during the heat of the day. Under cool, mild and hot air temperatures, E. rupestris were predominantly active in the morning and night, being the least active during midday. This shift in activity time, known as polyphasic activity, is common amongst Macroscelidea species and is a mechanism for escaping thermal extremes. To determine the effect of temperature on foraging behaviour, I ran giving-up density (GUD) experiments on E. rupestris under a range of environmental conditions. GUD experiments yielded no conclusive results as animals did not show a significant preference for foraging under certain thermal conditions, and rather foraged under a variety of air temperatures. Overall, E. rupestris showed risk adverse behaviour, trading-off thermoregulation with foraging and activity for self-preservation during hot periods of the day. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Jackson, Emily Anne
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424402 , vital:72150
- Description: The increase, and prolonged periods, of high ambient temperatures are cause for concern for small mammals living in arid areas of Southern Africa. In this study, I aimed to determine the effect of high environmental temperatures on the activity, body temperature maintenance and foraging behaviour in a population of Western rock elephant shrew, Elephantulus rupestris, in the Eastern Cape, South Africa. I found that E. rupestris maintained stable body temperatures (Tb = 37.31 °C ± 0.64) over a range of environmental temperatures (Tair = 5° to 33.9 °C), indicating their ability to remain normothermic during the heat of the day. Under cool, mild and hot air temperatures, E. rupestris were predominantly active in the morning and night, being the least active during midday. This shift in activity time, known as polyphasic activity, is common amongst Macroscelidea species and is a mechanism for escaping thermal extremes. To determine the effect of temperature on foraging behaviour, I ran giving-up density (GUD) experiments on E. rupestris under a range of environmental conditions. GUD experiments yielded no conclusive results as animals did not show a significant preference for foraging under certain thermal conditions, and rather foraged under a variety of air temperatures. Overall, E. rupestris showed risk adverse behaviour, trading-off thermoregulation with foraging and activity for self-preservation during hot periods of the day. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
The contentious relationship between feminist scholarship and university sexual violence policies: 1980-2021
- Authors: Roberts, Lily May
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425267 , vital:72224
- Description: This thesis tracks the historically contentious relationship between feminist scholarship and university sexual violence policies. It examines the rise of the managerial university in South Africa, and the overlapping development of sexual violence policies through feminist activism from the early 1990s. Through an examination of the sexual violence policies of the University of Cape Town, the University of the Witwatersrand, Rhodes University, Stellenbosch University, and the University of the Western Cape, this thesis argues that these policies are aimed at ‘managing’ the process of reporting, rather than dismantling the broader structures – both within the university and society as a whole – that lead to and enable sexual violence. In this way, sexual violence policies are governed by a managerial discourse, limiting the possibility of addressing the dismantling of structures and discourses that perpetuate sexual violence, which, as I argue, is fundamentally opposed to the intellectual and political project of feminist scholarship from which these sexual violence policies initially emerged. However, this thesis also argues that feminist scholarship is not immune to the influence of managerialism, as discourses of efficiency and effectiveness have shaped Gender and Women’s Studies, where feminist scholarship is often located. I use the #RUReferenceList protests that drew on black feminist scholarship and came under managerial control as an example of the contentious relationship between managerialism and feminist activism. , Thesis (MA) -- Faculty of Humanities, History, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Roberts, Lily May
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425267 , vital:72224
- Description: This thesis tracks the historically contentious relationship between feminist scholarship and university sexual violence policies. It examines the rise of the managerial university in South Africa, and the overlapping development of sexual violence policies through feminist activism from the early 1990s. Through an examination of the sexual violence policies of the University of Cape Town, the University of the Witwatersrand, Rhodes University, Stellenbosch University, and the University of the Western Cape, this thesis argues that these policies are aimed at ‘managing’ the process of reporting, rather than dismantling the broader structures – both within the university and society as a whole – that lead to and enable sexual violence. In this way, sexual violence policies are governed by a managerial discourse, limiting the possibility of addressing the dismantling of structures and discourses that perpetuate sexual violence, which, as I argue, is fundamentally opposed to the intellectual and political project of feminist scholarship from which these sexual violence policies initially emerged. However, this thesis also argues that feminist scholarship is not immune to the influence of managerialism, as discourses of efficiency and effectiveness have shaped Gender and Women’s Studies, where feminist scholarship is often located. I use the #RUReferenceList protests that drew on black feminist scholarship and came under managerial control as an example of the contentious relationship between managerialism and feminist activism. , Thesis (MA) -- Faculty of Humanities, History, 2023
- Full Text:
- Date Issued: 2023-10-13
The development and op timisation of a Theiler’s murine encephalomyelitis virus antiviral assay
- Authors: Naidoo, Urisha Tirah
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424677 , vital:72174
- Description: Picornaviruses belong to the Picornaviridae family which are one of the largest and most diverse family of RNA viruses that cause a broad spectrum of infections in both humans and animals. These diseases range from severe infections such as poliomyelitis, meningitis, myocarditis to mild illnesses such as the common cold. Picornavirus outbreaks are a worldwide threat as they are continuously occurring. A recent outbreak of foot-and-mouth disease caused by a picornavirus occurred in South Africa, resulting in a temporary ban on the movement of cattle. Currently, the FDA has not approved any antiviral drugs against this virus, increasing the urgency for identifying effective antivirals. Picornaviruses have similar genomes and capsid organisation as such, those that are non-hazardous to humans can be used as a model system. A Theiler’s murine encephalomyelitis virus (TMEV) strain GDVII and Baby Hamster Kidney fibroblasts (BHK-21 cells) was used as a replication system to develop and optimise a medium-throughput antiviral screening assay. The TMEV GDVII replication system in BHK-21 cells was validated, and preliminary experiments were performed that were necessary for the development of the TMEV GDVII antiviral assay. This was achieved by conducting a CPE assay to visually monitor the onset and development of CPE induced by TMEV GDVII. Plaque assays accurately quantified the number of infectious virus particles required for calculating the MOI in downstream experiments. Lastly, indirect immunofluorescence and Western blot analysis detected the expression of viral proteins using previously generated antibodies against the TMEV GDVII VP1 capsid and 2C protein, thereby confirming infection in BHK-21 cells. The development of robust and reproducible assays is an essential component in antiviral drug discovery. Therefore, the confirmed replication system was then used as a foundation to develop a medium-throughput CPE-based TMEV GDVII antiviral assay whereby the parameters were optimised to produce one of high quality. Firstly, the quantitation of viral-induced CPE was examined and confirmed in a 96-well plate using resazurin as a cell viability indicator. Each parameter was tested at varying conditions, and the optimal was concluded as 2 % FBS in the assay media, a 15 000 cells/well seeding density, infecting the cells with TMEV GDVII at an MOI of 0.00625 and measuring resazurin at an endpoint of 72 hpi. Furthermore, the parameters were ii validated by calculating the Z’- factor, which consistently produced scores above 0.5, indicative of a reliable, robust, reproducible antiviral assay. Currently, there are no inhibitors against TMEV GDVII that have been reported or confirmed in cell lines, animal models or clinical trials. Therefore, once the optimal assay parameters were selected, it presented an opportunity to assess whether potential compounds, including itraconazole (ITZ) and dipyridamole (DIP), possessed antiviral activity that could firstly, be utilised as a control inhibitor when screening compounds against TMEV GDVII and secondly, contribute to research on this virus. Additionally, the previously produced anti-TMEV GDVII capsid antibody was shown to neutralise viral infection and was also included as a potential control. The sensitivity of the cells towards DMSO, a solution in which the compounds were solubilised, was first investigated. It was found that concentrations above 1 % are toxic to the cells; as such, the final DMSO concentrations were always kept below 1 % when screening compounds. Lastly, the generation of dose-response curves aided in the conclusion that the antibody was the most suitable control inhibitor as it displayed potent antiviral activity and no cytotoxicity towards the cells. In contrast, ITZ and DIP did not possess effective antiviral action and were toxic to cells at high concentrations. Finally, after all the components of the medium-throughput TMEV GDVII antiviral assay were identified, it was possible to screen 24 compounds from a coumarin and marine natural product library for cell cytotoxicity and antiviral activity. After generating dose-response curves, it was concluded that no compound effectively inhibited virus-induced CPE, and most were toxic to cells at relatively high concentrations. In conclusion, this is the first study that describes the development and optimisation of a robust medium-throughput CPE-based antiviral assay that has immense potential to screen other libraries of compounds for antiviral activity against TMEV GDVII. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Naidoo, Urisha Tirah
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424677 , vital:72174
- Description: Picornaviruses belong to the Picornaviridae family which are one of the largest and most diverse family of RNA viruses that cause a broad spectrum of infections in both humans and animals. These diseases range from severe infections such as poliomyelitis, meningitis, myocarditis to mild illnesses such as the common cold. Picornavirus outbreaks are a worldwide threat as they are continuously occurring. A recent outbreak of foot-and-mouth disease caused by a picornavirus occurred in South Africa, resulting in a temporary ban on the movement of cattle. Currently, the FDA has not approved any antiviral drugs against this virus, increasing the urgency for identifying effective antivirals. Picornaviruses have similar genomes and capsid organisation as such, those that are non-hazardous to humans can be used as a model system. A Theiler’s murine encephalomyelitis virus (TMEV) strain GDVII and Baby Hamster Kidney fibroblasts (BHK-21 cells) was used as a replication system to develop and optimise a medium-throughput antiviral screening assay. The TMEV GDVII replication system in BHK-21 cells was validated, and preliminary experiments were performed that were necessary for the development of the TMEV GDVII antiviral assay. This was achieved by conducting a CPE assay to visually monitor the onset and development of CPE induced by TMEV GDVII. Plaque assays accurately quantified the number of infectious virus particles required for calculating the MOI in downstream experiments. Lastly, indirect immunofluorescence and Western blot analysis detected the expression of viral proteins using previously generated antibodies against the TMEV GDVII VP1 capsid and 2C protein, thereby confirming infection in BHK-21 cells. The development of robust and reproducible assays is an essential component in antiviral drug discovery. Therefore, the confirmed replication system was then used as a foundation to develop a medium-throughput CPE-based TMEV GDVII antiviral assay whereby the parameters were optimised to produce one of high quality. Firstly, the quantitation of viral-induced CPE was examined and confirmed in a 96-well plate using resazurin as a cell viability indicator. Each parameter was tested at varying conditions, and the optimal was concluded as 2 % FBS in the assay media, a 15 000 cells/well seeding density, infecting the cells with TMEV GDVII at an MOI of 0.00625 and measuring resazurin at an endpoint of 72 hpi. Furthermore, the parameters were ii validated by calculating the Z’- factor, which consistently produced scores above 0.5, indicative of a reliable, robust, reproducible antiviral assay. Currently, there are no inhibitors against TMEV GDVII that have been reported or confirmed in cell lines, animal models or clinical trials. Therefore, once the optimal assay parameters were selected, it presented an opportunity to assess whether potential compounds, including itraconazole (ITZ) and dipyridamole (DIP), possessed antiviral activity that could firstly, be utilised as a control inhibitor when screening compounds against TMEV GDVII and secondly, contribute to research on this virus. Additionally, the previously produced anti-TMEV GDVII capsid antibody was shown to neutralise viral infection and was also included as a potential control. The sensitivity of the cells towards DMSO, a solution in which the compounds were solubilised, was first investigated. It was found that concentrations above 1 % are toxic to the cells; as such, the final DMSO concentrations were always kept below 1 % when screening compounds. Lastly, the generation of dose-response curves aided in the conclusion that the antibody was the most suitable control inhibitor as it displayed potent antiviral activity and no cytotoxicity towards the cells. In contrast, ITZ and DIP did not possess effective antiviral action and were toxic to cells at high concentrations. Finally, after all the components of the medium-throughput TMEV GDVII antiviral assay were identified, it was possible to screen 24 compounds from a coumarin and marine natural product library for cell cytotoxicity and antiviral activity. After generating dose-response curves, it was concluded that no compound effectively inhibited virus-induced CPE, and most were toxic to cells at relatively high concentrations. In conclusion, this is the first study that describes the development and optimisation of a robust medium-throughput CPE-based antiviral assay that has immense potential to screen other libraries of compounds for antiviral activity against TMEV GDVII. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
The effect of piospheres on the ecology of insectivorous birds and their arthropod prey
- Authors: Balmer, Natasha Louise
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424380 , vital:72148
- Description: Desertification is the degradation of arid ecosystems that result in the loss of biodiversity. Piospheres are areas of local degradation around a central point due to overgrazing and increased herbivore presence. There is a paucity of information regarding the effect of localised degradation on arthropods and insectivorous birds. Both of these organisms play crucial roles in ecosystem functioning and stability and can be used as models to study ecosystem functioning. I investigated the effect of piospheres on arthropods and birds in the Eastern Cape province of South Africa. I found that the abundance and diversity of arthropods were significantly reduced inside the piospheres due to the lack of vegetation. Termites were a group specifically negatively impacted by piospheres, with a significant reduction in their presence inside the piosphere. The family composition of arthropods also changed inside and outside the piospheres, with Caelifera, Diptera and Formicidae being the most dominant groups. The diversity of birds was also significantly reduced due to the degradation inside the piospheres. Looking at insectivorous birds, I found that the reduction in both vegetation and arthropod prey availability resulted in non-random avoidance of piospheres. This shows that piospheres negatively impact both arthropods and birds. The results from my study are supported by other literature studying the effects of habitat degradation associated with desertification. Due to the similarities of degradation between piospheres and desertification I make the argument that piospheres can be studied as localised models of desertification. The decrease in vegetation and arthropod abundance and diversity was found to further impact the feeding success of insectivorous birds. Using piospheres as a model for desertification, I found that the foraging effort of birds is significantly reduced within a degraded area due to the lack of vegetation providing safety to arthropod prey species. In addition to this, the foraging efficiency of insectivorous birds is significantly reduced inside the piospheres due to the decreased arthropod abundance and diversity. This shows that inside the piospheres birds spend less time searching for insects and have fewer successful feeds. This has implications for desertification of arid environments where birds face hyperthermia. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Balmer, Natasha Louise
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424380 , vital:72148
- Description: Desertification is the degradation of arid ecosystems that result in the loss of biodiversity. Piospheres are areas of local degradation around a central point due to overgrazing and increased herbivore presence. There is a paucity of information regarding the effect of localised degradation on arthropods and insectivorous birds. Both of these organisms play crucial roles in ecosystem functioning and stability and can be used as models to study ecosystem functioning. I investigated the effect of piospheres on arthropods and birds in the Eastern Cape province of South Africa. I found that the abundance and diversity of arthropods were significantly reduced inside the piospheres due to the lack of vegetation. Termites were a group specifically negatively impacted by piospheres, with a significant reduction in their presence inside the piosphere. The family composition of arthropods also changed inside and outside the piospheres, with Caelifera, Diptera and Formicidae being the most dominant groups. The diversity of birds was also significantly reduced due to the degradation inside the piospheres. Looking at insectivorous birds, I found that the reduction in both vegetation and arthropod prey availability resulted in non-random avoidance of piospheres. This shows that piospheres negatively impact both arthropods and birds. The results from my study are supported by other literature studying the effects of habitat degradation associated with desertification. Due to the similarities of degradation between piospheres and desertification I make the argument that piospheres can be studied as localised models of desertification. The decrease in vegetation and arthropod abundance and diversity was found to further impact the feeding success of insectivorous birds. Using piospheres as a model for desertification, I found that the foraging effort of birds is significantly reduced within a degraded area due to the lack of vegetation providing safety to arthropod prey species. In addition to this, the foraging efficiency of insectivorous birds is significantly reduced inside the piospheres due to the decreased arthropod abundance and diversity. This shows that inside the piospheres birds spend less time searching for insects and have fewer successful feeds. This has implications for desertification of arid environments where birds face hyperthermia. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
The impacts of game farming on worker’s livelihoods: a case of a private game reserve in South Africa’s Eastern Cape Province
- Authors: Ngcoza, Nkosiphendule Mbasa
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425182 , vital:72217
- Description: Land use shifts from commercial agricultural farming to game farming through wildlife tourism, has been prevalent in post-apartheid South Africa. Scholars have argued that wildlife tourism to be more profitable than other forms of commercial farming. As such, game farming has been promoted as a community-engaged vehicle for rural development through the creation of better employment opportunities. This study explored the implications of these shifts on the livelihoods of farm workers living on the game farms. Unlike labour tenants, farm workers who live on the private game, earn a wage. However, farm workers’ accommodation on the game farm is dependent on them being employed on the farm. The aim of the study was to explore the impacts of game farms on the livelihoods of farm workers since the shift from commercial agricultural practices to tourism services in the form of private game reserves. A case study research design was used to gather in-depth information about the multiple realities of the participants, not only about their employment relationships, but also their experiences living on the property on which they are employed. I collected data mainly through semi-structured interviews. I also collected and analysed company documents. The study adopted a Sustainable Livelihoods Framework as a theoretical schema to analyse the livelihood assets readily available to the farm dwellers and the various livelihood strategies they used to make ends meet. The findings of the study revealed that residing on the game farm, although it provided access to free accommodation, tended to pose several challenges to the workers, including i) exploitative employment structures and ii) insecure land rights. The findings also revealed human capital development initiatives mandated for employees were not formally documented. As a result, employees were confined in their current employment. Consequently, the study revealed that participants who had been employed by the game farm for over a decade showed little evidence of enhanced livelihoods. The livelihood strategies of the participants were their basic employment wage, the use of money borrowing systems through stokvels, and informal trading such as selling sweets and chips in the game reserve villages where other workers live with their families. , Thesis (MA) -- Faculty of Humanities, Sociology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Ngcoza, Nkosiphendule Mbasa
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425182 , vital:72217
- Description: Land use shifts from commercial agricultural farming to game farming through wildlife tourism, has been prevalent in post-apartheid South Africa. Scholars have argued that wildlife tourism to be more profitable than other forms of commercial farming. As such, game farming has been promoted as a community-engaged vehicle for rural development through the creation of better employment opportunities. This study explored the implications of these shifts on the livelihoods of farm workers living on the game farms. Unlike labour tenants, farm workers who live on the private game, earn a wage. However, farm workers’ accommodation on the game farm is dependent on them being employed on the farm. The aim of the study was to explore the impacts of game farms on the livelihoods of farm workers since the shift from commercial agricultural practices to tourism services in the form of private game reserves. A case study research design was used to gather in-depth information about the multiple realities of the participants, not only about their employment relationships, but also their experiences living on the property on which they are employed. I collected data mainly through semi-structured interviews. I also collected and analysed company documents. The study adopted a Sustainable Livelihoods Framework as a theoretical schema to analyse the livelihood assets readily available to the farm dwellers and the various livelihood strategies they used to make ends meet. The findings of the study revealed that residing on the game farm, although it provided access to free accommodation, tended to pose several challenges to the workers, including i) exploitative employment structures and ii) insecure land rights. The findings also revealed human capital development initiatives mandated for employees were not formally documented. As a result, employees were confined in their current employment. Consequently, the study revealed that participants who had been employed by the game farm for over a decade showed little evidence of enhanced livelihoods. The livelihood strategies of the participants were their basic employment wage, the use of money borrowing systems through stokvels, and informal trading such as selling sweets and chips in the game reserve villages where other workers live with their families. , Thesis (MA) -- Faculty of Humanities, Sociology, 2023
- Full Text:
- Date Issued: 2023-10-13
The obligation of South Africa to provide social security to refugees and asylum seekers during the COVID-19 pandemic
- Authors: Dekeda, Awethu Zethu
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424119 , vital:72125
- Description: Covid-19 a novel pandemic, has wreaked havoc globally, threatening the livelihoods of all, including refugees and asylum seekers. Like all other countries globally, South Africa has gone to great lengths to mitigate the challenges that this pandemic has caused. However, it is far from clear whether these responses are according due regard to the rights of some of the most vulnerable in society, amongst which are refugees. This thesis deals with South Africa’s obligation to provide social security to refugees during the Covid-19 pandemic. It specifically assesses whether South Africa's responses to the Covid-19 pandemic were in adherence to fundamental refugee law principles relevant to the protection of refugees. The study commences with a general introduction, followed by an analysis of the international human rights and refugee law framework relevant to protection of refugees. This framework is used to assess South Africa’s responses. Subsequently, the discussion delves into South Africa’s own national framework on social security. Using the standards identified in both the national and international frameworks, the thesis then proceeds to measure South Africa’s Covid-19 related responses regarding social security to resolve the issue of whether South Africa adhered to these standards in as far the protection of refugees’ right to social security is concerned. , Thesis (LLM) -- Faculty of Law, Law, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Dekeda, Awethu Zethu
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424119 , vital:72125
- Description: Covid-19 a novel pandemic, has wreaked havoc globally, threatening the livelihoods of all, including refugees and asylum seekers. Like all other countries globally, South Africa has gone to great lengths to mitigate the challenges that this pandemic has caused. However, it is far from clear whether these responses are according due regard to the rights of some of the most vulnerable in society, amongst which are refugees. This thesis deals with South Africa’s obligation to provide social security to refugees during the Covid-19 pandemic. It specifically assesses whether South Africa's responses to the Covid-19 pandemic were in adherence to fundamental refugee law principles relevant to the protection of refugees. The study commences with a general introduction, followed by an analysis of the international human rights and refugee law framework relevant to protection of refugees. This framework is used to assess South Africa’s responses. Subsequently, the discussion delves into South Africa’s own national framework on social security. Using the standards identified in both the national and international frameworks, the thesis then proceeds to measure South Africa’s Covid-19 related responses regarding social security to resolve the issue of whether South Africa adhered to these standards in as far the protection of refugees’ right to social security is concerned. , Thesis (LLM) -- Faculty of Law, Law, 2023
- Full Text:
- Date Issued: 2023-10-13
The perspectives of some amaXhosa healthcare workers regarding mental distress: an interpretive phenomenological analysis
- Authors: Ngqamfana, Siphosethu
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425031 , vital:72203
- Description: Mental distress is a universal phenomenon experienced by many individuals despite age, race, gender, occupation, or socio-cultural context and is slowly becoming a major contributor to the burden of disease in South Africa. However, mental distress fails to take precedence in SA because of inherent intricacies in understandings about it, as a result of ways of being conceptualised and interpreted differently across cultures. This research study explored amaXhosa healthcare workers’ understandings, knowledge, practices, and attitudes regarding mental distress amongst some amaXhosa people. The study aimed to investigate what mental distress means for some people who belong to the amaXhosa ethnic group, to uncover how they conceptualise mental distress, seek help or what behaviours prevent help-seeking. It aimed to highlight any prevalent attitudes of stigma and discrimination, to build insight into overlooked aspects in psychotherapy practice especially when dealing with non-western populations. The study utilised interpretative phenomenological analysis (IPA) as its analytical lens; to explore and to enter as far as possible into the worlds of participants to generate rich data and in-depth analysis. Four participants were recruited through both purposive and snowball sampling and data were gathered using individual semi-structured interviews. From the data collected, the findings illustrate a limited understanding of mental distress amongst some amaXhosa people due to lack of education and awareness on the subject, leading to the apparent silence in discussing such matters and inadvertently predisposing it to being viewed as taboo. The predominant themes as evidenced by the data were the use of language that sensationalises mental distress; misinformation; Afrocentric beliefs that rationalise mental distress; alienation and segregation of those affected; and the primary healthcare system as a source of reinforcing prevalent stigma and discrimination. The findings show a link between constructs around mental distress and the prevalent socioiii cultural environment, denoting that some perspectives can be linked to observations or modelling in childhood, from people in the respective communities in which people live. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Ngqamfana, Siphosethu
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425031 , vital:72203
- Description: Mental distress is a universal phenomenon experienced by many individuals despite age, race, gender, occupation, or socio-cultural context and is slowly becoming a major contributor to the burden of disease in South Africa. However, mental distress fails to take precedence in SA because of inherent intricacies in understandings about it, as a result of ways of being conceptualised and interpreted differently across cultures. This research study explored amaXhosa healthcare workers’ understandings, knowledge, practices, and attitudes regarding mental distress amongst some amaXhosa people. The study aimed to investigate what mental distress means for some people who belong to the amaXhosa ethnic group, to uncover how they conceptualise mental distress, seek help or what behaviours prevent help-seeking. It aimed to highlight any prevalent attitudes of stigma and discrimination, to build insight into overlooked aspects in psychotherapy practice especially when dealing with non-western populations. The study utilised interpretative phenomenological analysis (IPA) as its analytical lens; to explore and to enter as far as possible into the worlds of participants to generate rich data and in-depth analysis. Four participants were recruited through both purposive and snowball sampling and data were gathered using individual semi-structured interviews. From the data collected, the findings illustrate a limited understanding of mental distress amongst some amaXhosa people due to lack of education and awareness on the subject, leading to the apparent silence in discussing such matters and inadvertently predisposing it to being viewed as taboo. The predominant themes as evidenced by the data were the use of language that sensationalises mental distress; misinformation; Afrocentric beliefs that rationalise mental distress; alienation and segregation of those affected; and the primary healthcare system as a source of reinforcing prevalent stigma and discrimination. The findings show a link between constructs around mental distress and the prevalent socioiii cultural environment, denoting that some perspectives can be linked to observations or modelling in childhood, from people in the respective communities in which people live. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-10-13
The relevance of career counselling in higher education: a study following students at a South African university
- Authors: Lewis, Christine
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432347 , vital:72863 , DOI 10.21504/10962/432348
- Description: Very few students in South Africa (SA) receive adequate career counselling at school and often arrive at institutions of higher learning without a clear sense of what their prospective careers will entail. The limited access to career counselling and assessment is further compounded by criticisms of popular career assessment instruments used in SA, where the primary goal of career counselling and assessment is to match clients to careers for job placement. This approach no longer serves the needs of a diverse SA population and disregards contextual influences on careers. Therefore, a need exists to understand and inform career counselling interventions and to guard against the provision of de-contextualised and contextually insensitive approaches. Moreover, changes in the workplace, where career change has become the norm as the world of work has moved away from stability and permanency to fluidity, calls for a contemporary response from career counselling theories, practitioners as well as researchers, to equip clients with the necessary skills to respond to these changes. Thus, SA institutions of higher learning need to innovate their practices to more inclusively, effectively, and justly serve the needs of a diverse student population for work success in a developing nation and a complex world. This study aimed to evaluate the relevance and effectiveness of a university’s career counselling services from the students’ perspectives. It focuses on gaining an indication of the perceived effectiveness of assessment measures used, and to ascertain the influences that impact on individual students’ career decision-making over the course of undergraduate studies. Due to the increasing recognition for the need to develop a contextualised approach to career development interventions, this study included the SACII, a locally developed interest inventory as part of a career assessment battery, with a group of university students. A pragmatic approach using mixed-methods was used. Multiple case studies of the career trajectories of a cohort of undergraduate students who had undertaken career assessments at the university career centre, were tracked longitudinally over the course of undergraduate studies. Data were generated through vignettes that included the 13 participants' career assessment reports, a service evaluation questionnaire and two successive follow-up interviews. Each participant's first follow-up interview occurred six months after their career assessment feedback session; and the second follow-up was in the final year of undergraduate studies, after eighteen months. Descriptive statistical analysis summarised the basic features of the quantitative data from the evaluation questionnaire. Thematic analysis was used for organisation and analysis of the follow-up interview data. Findings were that the career counselling and assessment facilitated greater self-knowledge in relation to career decision-making, assisted with selecting degree major subjects and enhanced career planning abilities. Using locally developed assessment measures in career counselling proved to be useful. Exploring career development from an overarching developmental contextual framework that is applicable and well-suited to the SA context provided a deeper understanding of contextual influences that impact on students' career decision-making processes. , Thesis (PhD) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Lewis, Christine
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432347 , vital:72863 , DOI 10.21504/10962/432348
- Description: Very few students in South Africa (SA) receive adequate career counselling at school and often arrive at institutions of higher learning without a clear sense of what their prospective careers will entail. The limited access to career counselling and assessment is further compounded by criticisms of popular career assessment instruments used in SA, where the primary goal of career counselling and assessment is to match clients to careers for job placement. This approach no longer serves the needs of a diverse SA population and disregards contextual influences on careers. Therefore, a need exists to understand and inform career counselling interventions and to guard against the provision of de-contextualised and contextually insensitive approaches. Moreover, changes in the workplace, where career change has become the norm as the world of work has moved away from stability and permanency to fluidity, calls for a contemporary response from career counselling theories, practitioners as well as researchers, to equip clients with the necessary skills to respond to these changes. Thus, SA institutions of higher learning need to innovate their practices to more inclusively, effectively, and justly serve the needs of a diverse student population for work success in a developing nation and a complex world. This study aimed to evaluate the relevance and effectiveness of a university’s career counselling services from the students’ perspectives. It focuses on gaining an indication of the perceived effectiveness of assessment measures used, and to ascertain the influences that impact on individual students’ career decision-making over the course of undergraduate studies. Due to the increasing recognition for the need to develop a contextualised approach to career development interventions, this study included the SACII, a locally developed interest inventory as part of a career assessment battery, with a group of university students. A pragmatic approach using mixed-methods was used. Multiple case studies of the career trajectories of a cohort of undergraduate students who had undertaken career assessments at the university career centre, were tracked longitudinally over the course of undergraduate studies. Data were generated through vignettes that included the 13 participants' career assessment reports, a service evaluation questionnaire and two successive follow-up interviews. Each participant's first follow-up interview occurred six months after their career assessment feedback session; and the second follow-up was in the final year of undergraduate studies, after eighteen months. Descriptive statistical analysis summarised the basic features of the quantitative data from the evaluation questionnaire. Thematic analysis was used for organisation and analysis of the follow-up interview data. Findings were that the career counselling and assessment facilitated greater self-knowledge in relation to career decision-making, assisted with selecting degree major subjects and enhanced career planning abilities. Using locally developed assessment measures in career counselling proved to be useful. Exploring career development from an overarching developmental contextual framework that is applicable and well-suited to the SA context provided a deeper understanding of contextual influences that impact on students' career decision-making processes. , Thesis (PhD) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-10-13
The use of dynamic software to potentially enhance conceptual understanding and a productive disposition in the visual learning of algebra: an interventionist case study
- Authors: Junius, Daniel Franscius
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/431542 , vital:72784 , DOI 10.21504/10962/431542
- Description: Over the decades, the didactics and practice of teaching mathematics has offered many unique challenges and opportunities for exploration and understanding. The introduction and development of technology into mathematics is one of the occurrences which has also contributed to a new discourse in teaching mathematics – in this case the teaching of algebra. Algebra is still seen as a gatekeeper and remains as one of the key reasons for a negative disposition amongst learners towards learning the subject. Across the globe psychologists, philosophers and educators continue to engage in debates and research projects in search of answers and solutions for the improvement of algebra teaching and an improvement in dispositions towards learning algebra. This thesis reports on a research project that focused on the use of dynamic software to enhance the conceptual understanding and productive dispositions of selected learners through the visual learning of abstract algebraic concepts. The research was executed as an interventionist case study. A case study methodological strategy was adopted with two groups of 30 Grade 9 learners. One group was a Grade 9 mathematics class of a school in Windhoek who scored above average in algebra but showed a very low disposition score, while the other group was made up of learners from a community project who scored high on the disposition scale but achieved below average results in algebra. The analytical framework of the case study is structured around a combination of complementary algebraic topics presented through visual learning, with GeoGebra as a medium of instruction. With the focus on visualisation and the use of technology the study investigated and attempted to understand how participants processed and internalised algebraic concepts to make sense of abstract algebraic concepts and eventually gain sustained conceptual understanding. The study was framed by the theoretical theories of constructivism and the Dual Coding Theory. For the collection of data, a mixed methods approach was adopted following three cycles. Three algebraic topics were taught with GeoGebra applets yielding both qualitative and quantitative data, through the observation of participants, screen captures and reflective interviews, using instruments designed specifically for the study and collecting quantitative achievement test results. The study, a journey that both the participants and the researcher embarked upon, revealed that the use of technology enhanced conceptual understanding for both groups and both groups showed a positive change in disposition towards learning algebra. The intervention with GeoGebra consistently and progressively improved in terms of conceptual understanding and dispositions towards learning algebra significant improvements in results were achieved. The findings showed that this approach to teaching algebra yielded positive results and gave new insights into visual teaching with technology. New opportunities for further research were created. , Thesis (PhD) -- Faculty of Education, Secondary and Post-School Education, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Junius, Daniel Franscius
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/431542 , vital:72784 , DOI 10.21504/10962/431542
- Description: Over the decades, the didactics and practice of teaching mathematics has offered many unique challenges and opportunities for exploration and understanding. The introduction and development of technology into mathematics is one of the occurrences which has also contributed to a new discourse in teaching mathematics – in this case the teaching of algebra. Algebra is still seen as a gatekeeper and remains as one of the key reasons for a negative disposition amongst learners towards learning the subject. Across the globe psychologists, philosophers and educators continue to engage in debates and research projects in search of answers and solutions for the improvement of algebra teaching and an improvement in dispositions towards learning algebra. This thesis reports on a research project that focused on the use of dynamic software to enhance the conceptual understanding and productive dispositions of selected learners through the visual learning of abstract algebraic concepts. The research was executed as an interventionist case study. A case study methodological strategy was adopted with two groups of 30 Grade 9 learners. One group was a Grade 9 mathematics class of a school in Windhoek who scored above average in algebra but showed a very low disposition score, while the other group was made up of learners from a community project who scored high on the disposition scale but achieved below average results in algebra. The analytical framework of the case study is structured around a combination of complementary algebraic topics presented through visual learning, with GeoGebra as a medium of instruction. With the focus on visualisation and the use of technology the study investigated and attempted to understand how participants processed and internalised algebraic concepts to make sense of abstract algebraic concepts and eventually gain sustained conceptual understanding. The study was framed by the theoretical theories of constructivism and the Dual Coding Theory. For the collection of data, a mixed methods approach was adopted following three cycles. Three algebraic topics were taught with GeoGebra applets yielding both qualitative and quantitative data, through the observation of participants, screen captures and reflective interviews, using instruments designed specifically for the study and collecting quantitative achievement test results. The study, a journey that both the participants and the researcher embarked upon, revealed that the use of technology enhanced conceptual understanding for both groups and both groups showed a positive change in disposition towards learning algebra. The intervention with GeoGebra consistently and progressively improved in terms of conceptual understanding and dispositions towards learning algebra significant improvements in results were achieved. The findings showed that this approach to teaching algebra yielded positive results and gave new insights into visual teaching with technology. New opportunities for further research were created. , Thesis (PhD) -- Faculty of Education, Secondary and Post-School Education, 2023
- Full Text:
- Date Issued: 2023-10-13