Just stories?: Epistemic (in)justice and everyday resistance in the digital stories of family literacy practices by Grade 1-5 workers at a South African University
- Authors: Viedge, Jane Margaret
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/432308 , vital:72860
- Description: This thesis sets out to establish in what ways digital storytelling (DST) revealed instances of epistemic (in)justices inherent in the family literacy intervention experiences of four Black, working-class parents employed at a South African University1. Additionally, it explores how DST might be used by the participants (self-labelled the Storytelling Family Literacy - SFL Advocates) to correct any harm done. The context for the research is based on the deep-rooted harms of Bantu education in which Black South Africans were denied equal access to resources such as literacy practices. I investigated these aims by using the theories of DST, Communication for Social Change (C4SC) and epistemic (in)justice. As a participatory media practice supporting communications in marginalised communities, DST’s broad purpose is to assist these communities in telling stories of their lived experiences in ways that change dominant and, therefore, unchallenged views about them (Servaes & Malikhao 2014). In facilitating DST workshops with the SFL Advocates, I searched for evidence of epistemic (in)justice to enhance our (all stakeholders) understanding of their literacy experiences in ways that addressed their credibility status as ‘knowers’ (Fricker, 2007). Viewed through this lens, utilising DST provided a mechanism for understanding the impact of social interventions in a university setting that aimed to correct past injustices. The process involved online and face-to-face workshops with the participants during the Covid-19 Lockdown. The online format hampered data collection processes, and I resorted to face-to-face interactions for the workshops and interviews. These interactions were distinctly different from those I had experienced with participants in previous workshops, and they became a key focus in my analysis. Using narrative inquiry with critical realist and interpretive analysis techniques to interrogate the data, I discovered DST has both weaknesses and strengths as a C4SC communication tool. My findings revealed participants who, in the moment of leading their children and communities through the family literacy intervention, could claim to have redressed epistemic harms from the legacy of Apartheid education. However, by reflecting on this moment, the participants brought to light an epistemic harm that had been previously left unspoken: their sense of restored credibility as knowledge-bearers during the intervention was deeply shaken when the programme ended because they felt abandoned by the university. Therefore, the epistemic (in)justice lens unveiled hidden injustices that curtailed the participants’ ability to participate fully in the DST workshops. They described suffering the effects of pernicious and arbitrary acts of epistemic injustice at the hands of the University. Their participation in my workshops was erratic, and their stories were incomplete. As a result, I experienced difficulty analysing what I perceived as a lack of data. Moreover, despite my independent researcher status, my positionality as participant-observer was problematic as the participants may have perceived me as representative of the University and its institutional power. I responded to the problematic data by including a new theoretical framework in my analysis: the theory of everyday resistance (Vinthagen & Johansson, 2013). Combined with epistemic (in)justice theory and Vivienne’s ideas of using DST for everyday activism, I theorised how the participants negotiated their expressions of identity in epistemically unjust spaces. To put institutional epistemic injustice in perspective in the context of the University, I drew on Fricker’s three models of epistemic justice that enable fair and free conditions for marginalised workers to communicate for social change. , Thesis (MA) -- Faculty of Humanities, Journalism and Media Studies, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Viedge, Jane Margaret
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/432308 , vital:72860
- Description: This thesis sets out to establish in what ways digital storytelling (DST) revealed instances of epistemic (in)justices inherent in the family literacy intervention experiences of four Black, working-class parents employed at a South African University1. Additionally, it explores how DST might be used by the participants (self-labelled the Storytelling Family Literacy - SFL Advocates) to correct any harm done. The context for the research is based on the deep-rooted harms of Bantu education in which Black South Africans were denied equal access to resources such as literacy practices. I investigated these aims by using the theories of DST, Communication for Social Change (C4SC) and epistemic (in)justice. As a participatory media practice supporting communications in marginalised communities, DST’s broad purpose is to assist these communities in telling stories of their lived experiences in ways that change dominant and, therefore, unchallenged views about them (Servaes & Malikhao 2014). In facilitating DST workshops with the SFL Advocates, I searched for evidence of epistemic (in)justice to enhance our (all stakeholders) understanding of their literacy experiences in ways that addressed their credibility status as ‘knowers’ (Fricker, 2007). Viewed through this lens, utilising DST provided a mechanism for understanding the impact of social interventions in a university setting that aimed to correct past injustices. The process involved online and face-to-face workshops with the participants during the Covid-19 Lockdown. The online format hampered data collection processes, and I resorted to face-to-face interactions for the workshops and interviews. These interactions were distinctly different from those I had experienced with participants in previous workshops, and they became a key focus in my analysis. Using narrative inquiry with critical realist and interpretive analysis techniques to interrogate the data, I discovered DST has both weaknesses and strengths as a C4SC communication tool. My findings revealed participants who, in the moment of leading their children and communities through the family literacy intervention, could claim to have redressed epistemic harms from the legacy of Apartheid education. However, by reflecting on this moment, the participants brought to light an epistemic harm that had been previously left unspoken: their sense of restored credibility as knowledge-bearers during the intervention was deeply shaken when the programme ended because they felt abandoned by the university. Therefore, the epistemic (in)justice lens unveiled hidden injustices that curtailed the participants’ ability to participate fully in the DST workshops. They described suffering the effects of pernicious and arbitrary acts of epistemic injustice at the hands of the University. Their participation in my workshops was erratic, and their stories were incomplete. As a result, I experienced difficulty analysing what I perceived as a lack of data. Moreover, despite my independent researcher status, my positionality as participant-observer was problematic as the participants may have perceived me as representative of the University and its institutional power. I responded to the problematic data by including a new theoretical framework in my analysis: the theory of everyday resistance (Vinthagen & Johansson, 2013). Combined with epistemic (in)justice theory and Vivienne’s ideas of using DST for everyday activism, I theorised how the participants negotiated their expressions of identity in epistemically unjust spaces. To put institutional epistemic injustice in perspective in the context of the University, I drew on Fricker’s three models of epistemic justice that enable fair and free conditions for marginalised workers to communicate for social change. , Thesis (MA) -- Faculty of Humanities, Journalism and Media Studies, 2023
- Full Text:
- Date Issued: 2023-10-13
M3: Mining Mini-Halos with MeerKAT
- Authors: Trehaeven, Keegan Somerset
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424754 , vital:72181
- Description: This work aims to showcase the MeerKAT telescope’s capabilities and related calibration and imaging software in studying the emission of radio mini-halos. These diffuse radio synchrotron sources surround a Brightest Cluster Galaxy (BCG) in relatively relaxed clusters out to a few 100 kpc in size. They are difficult to image because of their relatively low surface brightness and small angular size. Hence, they could not be studied in great detail by previous generations of radio telescopes and much about their nature, particularly the exact production mechanism, is not yet fully understood. Thus, for the first time, MeerKAT observed a sample of five galaxy clusters to investigate the central radio mini-halo in each. Studying these sources requires the deepest images generated from the data and the effective subtraction of any projected sources obscuring or contaminating the underlying diffuse emission. Therefore, I describe the data reduction used to create third-generation calibrated, primary beam corrected, point source subtracted Stokes I L-band continuum images of these clusters. For first- and second-generation calibration, I use the CARACal pipeline, which implements software optimised explicitly for MeerKAT data. For third-generation calibration, I use the faceted approach of killMS and DDFacet, and then I perform visibility-plane point source subtraction to disentangle the compact and diffuse emissions. I then measured the size, flux density, in-band spectral properties, and radio power of the central mini-halos. I present the first new mini-halo detection by MeerKAT (MACS J2140.2-2339, Trehaeven et al. accepted), the first spectral index maps of these mini-halos, which show very interesting distributions, and a ∼100 kpc II southern extension to the ACO 3444 mini-halo previously unseen in archival VLA data. Thereafter, I present a multi-wavelength case study for two complementary mini-halos from our sample and show via a radio-to-X-ray spatial correlation test that they might be caused by different particle (re)-acceleration mechanisms. Through these initial science results, I have shown that future observations of radio mini-halos with MeerKAT are an exciting prospect that can lead to a better understanding of the fundamental physics behind these sources. , Thesis (MSc) -- Faculty of Science, Physics and Electronics, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Trehaeven, Keegan Somerset
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424754 , vital:72181
- Description: This work aims to showcase the MeerKAT telescope’s capabilities and related calibration and imaging software in studying the emission of radio mini-halos. These diffuse radio synchrotron sources surround a Brightest Cluster Galaxy (BCG) in relatively relaxed clusters out to a few 100 kpc in size. They are difficult to image because of their relatively low surface brightness and small angular size. Hence, they could not be studied in great detail by previous generations of radio telescopes and much about their nature, particularly the exact production mechanism, is not yet fully understood. Thus, for the first time, MeerKAT observed a sample of five galaxy clusters to investigate the central radio mini-halo in each. Studying these sources requires the deepest images generated from the data and the effective subtraction of any projected sources obscuring or contaminating the underlying diffuse emission. Therefore, I describe the data reduction used to create third-generation calibrated, primary beam corrected, point source subtracted Stokes I L-band continuum images of these clusters. For first- and second-generation calibration, I use the CARACal pipeline, which implements software optimised explicitly for MeerKAT data. For third-generation calibration, I use the faceted approach of killMS and DDFacet, and then I perform visibility-plane point source subtraction to disentangle the compact and diffuse emissions. I then measured the size, flux density, in-band spectral properties, and radio power of the central mini-halos. I present the first new mini-halo detection by MeerKAT (MACS J2140.2-2339, Trehaeven et al. accepted), the first spectral index maps of these mini-halos, which show very interesting distributions, and a ∼100 kpc II southern extension to the ACO 3444 mini-halo previously unseen in archival VLA data. Thereafter, I present a multi-wavelength case study for two complementary mini-halos from our sample and show via a radio-to-X-ray spatial correlation test that they might be caused by different particle (re)-acceleration mechanisms. Through these initial science results, I have shown that future observations of radio mini-halos with MeerKAT are an exciting prospect that can lead to a better understanding of the fundamental physics behind these sources. , Thesis (MSc) -- Faculty of Science, Physics and Electronics, 2023
- Full Text:
- Date Issued: 2023-10-13
Marine plastic pollution impacts on ecosystem services and livelihoods in South Africa: a review and stakeholder perceptions
- Authors: Yose, Papama
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424743 , vital:72180
- Description: Marine plastic pollution is one of the major environmental problems globally, with adverse impacts on marine ecosystem services, functions and benefits and people. Yet, compared to plastic pollution impacts on terrestrial ecosystems, the impacts of plastic waste on marine ecosystems are little studied and poorly understood in South Africa. In response, research interest on the ecological and economic impacts of marine plastic pollution has grown rapidly but socio-cultural impacts remain poorly conceptualized and little understudied. This trend is arguably driven by the dominance of a quantitative paradigm which is arguably inadequate to respond to dynamic socio-cultural issues and contexts. Further, in South Africa, marine ecosystems are used by diverse groups of people ranging from subsistence users, tourism operators, commercial fishers and recreational users, meaning that addressing marine plastic pollution requires a multi-stakeholder approach. However, few studies explore the perceptions of diverse stakeholders regarding marine plastic pollution, its impacts and potential interventions. Against this background, the objective of the thesis are twofold: (a) to argue for a more nuanced understanding of marine plastic pollution impacts on human well-being in order to strengthen conceptualization of impacts that goes beyond direct and quantitatively measured impacts (ecological, health and economic) but considers the socio-cultural dimensions of impacts (lifestyle disruptions, mental health costs and cultural and heritage impacts), and (b) examine stakeholders’ perceptions of marine plastic pollution, its impacts and potential interventions in South Africa. Drawing on case studies, this study provides a working definition of the socio-cultural impacts of marine plastic pollution and a conceptual framework for categorizing the impacts. It highlights three dimensions of the socio-cultural impacts of marine plastic pollution (lifestyle, mental health, and cultural and heritage impacts). It also illustrates connections between marine ecosystems and marine-based livelihood activities with the social and cultural dimensions of human wellbeing to show the links between marine environments and socio-cultural contexts. Concerning stakeholder perceptions, the study showed a tendency to associate marine plastic pollution with immediate, noticeable and easily quantifiable ecological impacts such as entanglement and ingestion of marine organisms, economic impacts and social impacts (e.g., loss of aesthetic appeal). However, secondary impacts such as loss of marine biodiversity and social impacts such as human health, were largely unknown. Moreover, there was heterogeneity in perceptions of marine plastic pollution impacts among the stakeholder groups. Prospective studies researching marine plastic pollution impacts should consider divergent and diverse perceptions of different stakeholders to capture the real costs of marine plastic pollution. , Thesis (MSc) -- Faculty of Science, Environmental Science, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Yose, Papama
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424743 , vital:72180
- Description: Marine plastic pollution is one of the major environmental problems globally, with adverse impacts on marine ecosystem services, functions and benefits and people. Yet, compared to plastic pollution impacts on terrestrial ecosystems, the impacts of plastic waste on marine ecosystems are little studied and poorly understood in South Africa. In response, research interest on the ecological and economic impacts of marine plastic pollution has grown rapidly but socio-cultural impacts remain poorly conceptualized and little understudied. This trend is arguably driven by the dominance of a quantitative paradigm which is arguably inadequate to respond to dynamic socio-cultural issues and contexts. Further, in South Africa, marine ecosystems are used by diverse groups of people ranging from subsistence users, tourism operators, commercial fishers and recreational users, meaning that addressing marine plastic pollution requires a multi-stakeholder approach. However, few studies explore the perceptions of diverse stakeholders regarding marine plastic pollution, its impacts and potential interventions. Against this background, the objective of the thesis are twofold: (a) to argue for a more nuanced understanding of marine plastic pollution impacts on human well-being in order to strengthen conceptualization of impacts that goes beyond direct and quantitatively measured impacts (ecological, health and economic) but considers the socio-cultural dimensions of impacts (lifestyle disruptions, mental health costs and cultural and heritage impacts), and (b) examine stakeholders’ perceptions of marine plastic pollution, its impacts and potential interventions in South Africa. Drawing on case studies, this study provides a working definition of the socio-cultural impacts of marine plastic pollution and a conceptual framework for categorizing the impacts. It highlights three dimensions of the socio-cultural impacts of marine plastic pollution (lifestyle, mental health, and cultural and heritage impacts). It also illustrates connections between marine ecosystems and marine-based livelihood activities with the social and cultural dimensions of human wellbeing to show the links between marine environments and socio-cultural contexts. Concerning stakeholder perceptions, the study showed a tendency to associate marine plastic pollution with immediate, noticeable and easily quantifiable ecological impacts such as entanglement and ingestion of marine organisms, economic impacts and social impacts (e.g., loss of aesthetic appeal). However, secondary impacts such as loss of marine biodiversity and social impacts such as human health, were largely unknown. Moreover, there was heterogeneity in perceptions of marine plastic pollution impacts among the stakeholder groups. Prospective studies researching marine plastic pollution impacts should consider divergent and diverse perceptions of different stakeholders to capture the real costs of marine plastic pollution. , Thesis (MSc) -- Faculty of Science, Environmental Science, 2023
- Full Text:
- Date Issued: 2023-10-13
Native-range studies on insect herbivores associated with African Lovegrass (Eragrostis curvula) in South Africa: prospects for biological control in Australia
- Authors: Yell, Liam Dougal
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424446 , vital:72154
- Description: Eragrostis curvula (Schrad.) Nees. (African Lovegrass) is an African native species of grass that was intentionally introduced for pasture in Australia. It has since escaped cultivation and has become widespread and highly invasive. Eragrostis curvula has been recorded in every state and territory in Australia where it has altered fire regimes, disrupted nutrient cycles and can reduce livestock carrying capacity by up to 50%. The Centre for Biological Control at Rhodes University and the New South Wales Department of Primary Industries have been working in collaboration to identify and screen herbivorous insects as biological control agents for E. curvula in Australia. Native-range surveys were conducted between 2021 and 2022 on E. curvula at twenty-two sites across South Africa to identify herbivorous natural enemies associated with it. Species accumulation curves were generated to ensure adequate sampling was performed to identify all the insects associated with E. curvula. Twenty-nine non-target grass species were surveyed simultaneously to determine the field-host range of the natural enemies associated with the target weed. Herbivorous natural enemies were prioritised as possible biological control agents against E. curvula in Australia based on field-host range, predicted efficacy and climatic suitability. Four insect species were consistently found on E. curvula, two of which were herbivorous, as well as a parasitoid and a detritivore. Species accumulation curves show that the insect community was adequately sampled in South Africa. The two herbivorous insects were identified to the lowest taxonomic level using COI barcoding. Both species are undescribed phytophagous wasps in the genus Tetramesa (Hymenoptera: Eurytomidae). Because Tetramesa species have been shown to be host specific and highly damaging in previous biological control programs for other invasive grass weeds, we assessed their suitability as candidate biological control agents for use on E. curvula in Australia. Both Tetramesa species (“sp. 4” and “sp. 5”) were found on several native congeners under field conditions in South Africa. Congeneric South African-native non-target grass species were used as phylogenetic proxies to assess the risk posed to Australian native Eragrostis species. This highlighted three non-target Australian native Eragrostis species, namely: E. parviflora (R. Br.) Trin., E. leptocarpa Benth. fl., and E. trachycarpa Benth., that are at risk of being attacked by the two candidate agents based on their phylogenetic proximity to E. curvula. Predicted efficacy trials were conducted at five long-term repeat survey sites and revealed that Tetramesa sp. 4 does not reduce the probability of E. curvula tiller survival or reproduction, while Tetramesa sp. 5 does not reduce the probability of tiller reproduction but does increase the probability of tiller survival. This result was unexpected and may be a plant compensatory response to herbivory. The sites where both Tetramesa species were collected in South Africa are climatically similar to the invaded range of E. curvula in Australia, and as such, the Tetramesa spp. are likely to be suitably adapted to the climate where they would be released in Australia. These results suggest that both Tetramesa species associated with E. curvula may have too broad a host range to be used as biological control agents in Australia. However, further quarantine-based host-range assessments on Australian native Eragrostis species are recommended to confirm this. The field-based methods used in this study have reduced the number of insect and plant species that host-range assessments will be required to be performed on, thus preventing wasted resources. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Yell, Liam Dougal
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424446 , vital:72154
- Description: Eragrostis curvula (Schrad.) Nees. (African Lovegrass) is an African native species of grass that was intentionally introduced for pasture in Australia. It has since escaped cultivation and has become widespread and highly invasive. Eragrostis curvula has been recorded in every state and territory in Australia where it has altered fire regimes, disrupted nutrient cycles and can reduce livestock carrying capacity by up to 50%. The Centre for Biological Control at Rhodes University and the New South Wales Department of Primary Industries have been working in collaboration to identify and screen herbivorous insects as biological control agents for E. curvula in Australia. Native-range surveys were conducted between 2021 and 2022 on E. curvula at twenty-two sites across South Africa to identify herbivorous natural enemies associated with it. Species accumulation curves were generated to ensure adequate sampling was performed to identify all the insects associated with E. curvula. Twenty-nine non-target grass species were surveyed simultaneously to determine the field-host range of the natural enemies associated with the target weed. Herbivorous natural enemies were prioritised as possible biological control agents against E. curvula in Australia based on field-host range, predicted efficacy and climatic suitability. Four insect species were consistently found on E. curvula, two of which were herbivorous, as well as a parasitoid and a detritivore. Species accumulation curves show that the insect community was adequately sampled in South Africa. The two herbivorous insects were identified to the lowest taxonomic level using COI barcoding. Both species are undescribed phytophagous wasps in the genus Tetramesa (Hymenoptera: Eurytomidae). Because Tetramesa species have been shown to be host specific and highly damaging in previous biological control programs for other invasive grass weeds, we assessed their suitability as candidate biological control agents for use on E. curvula in Australia. Both Tetramesa species (“sp. 4” and “sp. 5”) were found on several native congeners under field conditions in South Africa. Congeneric South African-native non-target grass species were used as phylogenetic proxies to assess the risk posed to Australian native Eragrostis species. This highlighted three non-target Australian native Eragrostis species, namely: E. parviflora (R. Br.) Trin., E. leptocarpa Benth. fl., and E. trachycarpa Benth., that are at risk of being attacked by the two candidate agents based on their phylogenetic proximity to E. curvula. Predicted efficacy trials were conducted at five long-term repeat survey sites and revealed that Tetramesa sp. 4 does not reduce the probability of E. curvula tiller survival or reproduction, while Tetramesa sp. 5 does not reduce the probability of tiller reproduction but does increase the probability of tiller survival. This result was unexpected and may be a plant compensatory response to herbivory. The sites where both Tetramesa species were collected in South Africa are climatically similar to the invaded range of E. curvula in Australia, and as such, the Tetramesa spp. are likely to be suitably adapted to the climate where they would be released in Australia. These results suggest that both Tetramesa species associated with E. curvula may have too broad a host range to be used as biological control agents in Australia. However, further quarantine-based host-range assessments on Australian native Eragrostis species are recommended to confirm this. The field-based methods used in this study have reduced the number of insect and plant species that host-range assessments will be required to be performed on, thus preventing wasted resources. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
Octa carboxy metal (II) phthalocyanine covalent films as pH sensitive electrochemical sensor for neurotransmitters
- Authors: Moyo, Iphithuli
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424525 , vital:72161
- Description: Octa acyl chloride metallophthalocyanines of cobalt (CoOAClPc) and iron (FeOAClPc) were synthesized and characterized using spectroscopic and electrochemical techniques. The metallophthalocyanines were fabricated as thin films onto phenylethylamine (PEA) pre-grafted Au electrode following a covalent amide reaction. The spectroscopic and electrochemical characterization confirmed the modification of the bare Au with PEA monolayer thin film (Au-PEA) and the covalent immobilization of MOAClPc to yield Au-PEA-MOAClPc (where M is Co and Fe). The acyl chloride functional groups were hydrolyzed forming pH sensitive thin films of terminal carboxylic acid (-COOH) functional groups (Au-PEA-MOCAPc). The Au-PEA-MOCAPc electrode exhibited pH selectivity and sensitivity properties towards the negatively charged [Fe(CN)6]3-/4- and positively charged [Ru(NH3)6]2+/3+ redox probes. The Au-PEA-MOCAPc electrodes were studied for their electrocatalytic and electroanalytical properties towards the detection of catecholamine neurotransmitters; dopamine (DA), epinephrine (EP) and norepinephrine (NOR). The electrodes were further investigated in the screening of ascorbic and uric acids by means of pH sensitive functional groups. The modification process exhibited good reproducibility. Excellent electrocatalytic and electroanalytical properties were observed. The limits of detection (LOD) determined using 3σ/m was found to be 64 nM, 0.22 μM and 0.17 μM for DA, EP and NOR respectively using Au-PEA-CoOCAPc. For Au-PEA-FeOCAPc, the LOD was found to 0.24 μM, 0.45 μM and 0.34 μM for DA, EP and NOR respectively. The Au-PEA-MOCAPc electrodes screened off the strong interferents, ascorbic and uric acid. The Au-PEA-FeOCAPc electrode was evaluated for its potential application in real sample analysis using new born calf serum, and it showed excellent percentage recoveries. , Thesis (MSc) -- Faculty of Science, Chemistry, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Moyo, Iphithuli
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424525 , vital:72161
- Description: Octa acyl chloride metallophthalocyanines of cobalt (CoOAClPc) and iron (FeOAClPc) were synthesized and characterized using spectroscopic and electrochemical techniques. The metallophthalocyanines were fabricated as thin films onto phenylethylamine (PEA) pre-grafted Au electrode following a covalent amide reaction. The spectroscopic and electrochemical characterization confirmed the modification of the bare Au with PEA monolayer thin film (Au-PEA) and the covalent immobilization of MOAClPc to yield Au-PEA-MOAClPc (where M is Co and Fe). The acyl chloride functional groups were hydrolyzed forming pH sensitive thin films of terminal carboxylic acid (-COOH) functional groups (Au-PEA-MOCAPc). The Au-PEA-MOCAPc electrode exhibited pH selectivity and sensitivity properties towards the negatively charged [Fe(CN)6]3-/4- and positively charged [Ru(NH3)6]2+/3+ redox probes. The Au-PEA-MOCAPc electrodes were studied for their electrocatalytic and electroanalytical properties towards the detection of catecholamine neurotransmitters; dopamine (DA), epinephrine (EP) and norepinephrine (NOR). The electrodes were further investigated in the screening of ascorbic and uric acids by means of pH sensitive functional groups. The modification process exhibited good reproducibility. Excellent electrocatalytic and electroanalytical properties were observed. The limits of detection (LOD) determined using 3σ/m was found to be 64 nM, 0.22 μM and 0.17 μM for DA, EP and NOR respectively using Au-PEA-CoOCAPc. For Au-PEA-FeOCAPc, the LOD was found to 0.24 μM, 0.45 μM and 0.34 μM for DA, EP and NOR respectively. The Au-PEA-MOCAPc electrodes screened off the strong interferents, ascorbic and uric acid. The Au-PEA-FeOCAPc electrode was evaluated for its potential application in real sample analysis using new born calf serum, and it showed excellent percentage recoveries. , Thesis (MSc) -- Faculty of Science, Chemistry, 2023
- Full Text:
- Date Issued: 2023-10-13
Origin and metallogenic significance of alkali metasomatism in the Paleoproterozoic Mapedi Formation, Kalahari Manganese Field, South Africa
- Authors: Ikwen, Emmanuella Biye
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424632 , vital:72170
- Description: The occurrence of alkali-rich metasomatic assemblages has been widely reported in various regions of the Kalahari Manganese Field (KMF). This alkali metasomatism has been characterized by the secondary introduction of elements such as K, Na, Li, Ba, P, V, Zn, As, amongst others. This study further explores the possibility of widespread alkali metasomatism in the KMF by reporting on and examining the occurrence of sugilite and other alkali-rich minerals at the contact between the Transvaal and Olifantshoek Supergroups in the Hotazel Mine area of the north-eastern KMF. The lithologies observed at the contact show macroscopic (such as cross cutting veins) and microscopic evidence of hydrothermal alteration. Using analytical methods such as X-ray diffraction, X-ray fluorescence, and scanning electron microscopy, results showed that in the north-eastern region of the KMF, the metasomatism observed at the Transvaal-Olifantshoek contact is mainly characterized by enrichment in sodium, and the occurrence of sodium minerals, predominantly in the form of aegirine. The aegirine forms exclusively in the quartzites of the Mapedi Formation along with minerals such as sugilite, baryte, banalsite, amongst others. Albite also occurs within the quartzites, but also within the Mapedi red shales. The secondary nature of these minerals is established by geochemical comparisons with pristine, as well as alkali-metasomatized samples of the same formation which were obtained from other parts of the KMF and Postmasburg. These comparisons showed that the Mapedi quartzites in the north-eastern KMF have undergone extensive oxidation compared to samples of the same formation which were obtained from Postmasburg. The north-eastern quartzites have an average hematite abundance of 17 wt.% compared to Postmasburg quartzite which have an average of 7 wt.% hematite. Furthermore, some quartzite samples contained up to 40 wt.% in hematite content. The comparisons also showed that Mapedi quartzites from the north-eastern KMF are substantially more sodium enriched compared to Mapedi quartzites from the Postmasburg region, which on average have sodium oxide content below detection limits. Geochemical comparisons were made between pristine Hotazel Formation samples from north-western KMF (Gloria Mine) and samples obtained from the north-eastern KMF (Hotazel Mine). Results showed that the samples obtained from the top of the Hotazel Formation (in the Hotazel mine area) are likely altered hematite lutite and not Banded Iron Formation, evident by their substantially high manganese oxide content (over 30 wt.% in some cases). When compared to pristine samples, the lutite also showed evidence of hydrothermal alteration, predominantly in the form of phosphate and barium enrichment, evident by the occurrence of baryte and apatite. The alkali metasomatism occurring at the contact between the Transvaal and Olifantshoek Supergroups was shown to be predominantly characterized by enrichment in Na, K, Li, Al, Ba, Sr, and P. The metasomatism characterized in this study was also proposed to possibly post-date an earlier metasomatic event which was characterized by leaching of silica and extensive oxidation of the rocks observed at the Transvaal-Olifantshoek contact in the north-eastern KMF. The occurrence of the alkali-rich minerals outlined above geochemically parallels other alkali-rich metasomatic assemblages reported in other parts of the KMF, as well as in the Postmasburg Manganese Field. Thus, based on the consistent occurrence of secondary, alkali-rich mineral assemblages across the KMF, characterized by the common occurrence of aegirine along with minerals such as sugilite and albite, there is evidence of a large-scale alkali metasomatism in the KMF. This study also explores the possible role that the Transvaal-Olifantshoek unconformity might have played in acting as a major conduit for fluid propagation because the observed mineral assemblages occur right at the contact between the Hotazel and Mapedi Formations. The occurrence of the alkali-rich minerals predominantly around the unconformity, as well as the relative depletion of phosphates in stratigraphically deeper parts of the Hotazel suggest that the fluid metasomatism was aided by the Olifantshoek-Transvaal unconformity surface. This study concludes that there is evidence for a strong link between the metasomatism occurring at the contact between the Hotazel and Mapedi formations (in the north-eastern KMF) and what is observed in the broader KMF region. , Thesis (MSc) -- Faculty of Science, Geology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Ikwen, Emmanuella Biye
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424632 , vital:72170
- Description: The occurrence of alkali-rich metasomatic assemblages has been widely reported in various regions of the Kalahari Manganese Field (KMF). This alkali metasomatism has been characterized by the secondary introduction of elements such as K, Na, Li, Ba, P, V, Zn, As, amongst others. This study further explores the possibility of widespread alkali metasomatism in the KMF by reporting on and examining the occurrence of sugilite and other alkali-rich minerals at the contact between the Transvaal and Olifantshoek Supergroups in the Hotazel Mine area of the north-eastern KMF. The lithologies observed at the contact show macroscopic (such as cross cutting veins) and microscopic evidence of hydrothermal alteration. Using analytical methods such as X-ray diffraction, X-ray fluorescence, and scanning electron microscopy, results showed that in the north-eastern region of the KMF, the metasomatism observed at the Transvaal-Olifantshoek contact is mainly characterized by enrichment in sodium, and the occurrence of sodium minerals, predominantly in the form of aegirine. The aegirine forms exclusively in the quartzites of the Mapedi Formation along with minerals such as sugilite, baryte, banalsite, amongst others. Albite also occurs within the quartzites, but also within the Mapedi red shales. The secondary nature of these minerals is established by geochemical comparisons with pristine, as well as alkali-metasomatized samples of the same formation which were obtained from other parts of the KMF and Postmasburg. These comparisons showed that the Mapedi quartzites in the north-eastern KMF have undergone extensive oxidation compared to samples of the same formation which were obtained from Postmasburg. The north-eastern quartzites have an average hematite abundance of 17 wt.% compared to Postmasburg quartzite which have an average of 7 wt.% hematite. Furthermore, some quartzite samples contained up to 40 wt.% in hematite content. The comparisons also showed that Mapedi quartzites from the north-eastern KMF are substantially more sodium enriched compared to Mapedi quartzites from the Postmasburg region, which on average have sodium oxide content below detection limits. Geochemical comparisons were made between pristine Hotazel Formation samples from north-western KMF (Gloria Mine) and samples obtained from the north-eastern KMF (Hotazel Mine). Results showed that the samples obtained from the top of the Hotazel Formation (in the Hotazel mine area) are likely altered hematite lutite and not Banded Iron Formation, evident by their substantially high manganese oxide content (over 30 wt.% in some cases). When compared to pristine samples, the lutite also showed evidence of hydrothermal alteration, predominantly in the form of phosphate and barium enrichment, evident by the occurrence of baryte and apatite. The alkali metasomatism occurring at the contact between the Transvaal and Olifantshoek Supergroups was shown to be predominantly characterized by enrichment in Na, K, Li, Al, Ba, Sr, and P. The metasomatism characterized in this study was also proposed to possibly post-date an earlier metasomatic event which was characterized by leaching of silica and extensive oxidation of the rocks observed at the Transvaal-Olifantshoek contact in the north-eastern KMF. The occurrence of the alkali-rich minerals outlined above geochemically parallels other alkali-rich metasomatic assemblages reported in other parts of the KMF, as well as in the Postmasburg Manganese Field. Thus, based on the consistent occurrence of secondary, alkali-rich mineral assemblages across the KMF, characterized by the common occurrence of aegirine along with minerals such as sugilite and albite, there is evidence of a large-scale alkali metasomatism in the KMF. This study also explores the possible role that the Transvaal-Olifantshoek unconformity might have played in acting as a major conduit for fluid propagation because the observed mineral assemblages occur right at the contact between the Hotazel and Mapedi Formations. The occurrence of the alkali-rich minerals predominantly around the unconformity, as well as the relative depletion of phosphates in stratigraphically deeper parts of the Hotazel suggest that the fluid metasomatism was aided by the Olifantshoek-Transvaal unconformity surface. This study concludes that there is evidence for a strong link between the metasomatism occurring at the contact between the Hotazel and Mapedi formations (in the north-eastern KMF) and what is observed in the broader KMF region. , Thesis (MSc) -- Faculty of Science, Geology, 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
Phytoplankton and aquatic macroinvertebrate assemblages from coastal and inland lakes of South Africa
- Authors: Nkibi, Esethu
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424435 , vital:72153
- Description: Freshwater lakes are generally defined as permanent natural standing water bodies, with some of them having a direct and indirect connection with groundwater, rivers, and the ocean. Freshwater lakes provide essential socio-economic and ecological goods and services including recreation, aesthetic, support aquatic biodiversity, food in a form of fisheries and water for domestic use. Given their critical role in sustainability in providing socio-economic services, freshwater lakes are among the most threatened ecosystems globally due to intense human impacts over the last decades. South Africa has limited freshwater lakes, which according to the National Biodiversity Assessment (NBA 2018), we know little about their current biology except historic aquatic biodiversity studies conducted in the early 1940s. There are no management strategies in place to protect and conserve freshwater lake biodiversity and important ecosystem services. This thesis aims to: (1) produce a biodiversity inventory of phytoplankton and aquatic macroinvertebrate species and, (2) investigate important environmental drivers responsible for phytoplankton and aquatic macroinvertebrate species composition from six South African freshwater lakes. It was hypothesized that the three lake types will show different phytoplankton and aquatic macroinvertebrates species composition attributed by the geographical region (coastal and inland lake) and related physico-chemical parameters. Study sites consisted of two Northern KwaZulu-Natal coastal lakes (hereafter Coastal Lakes, CL) i.e., Lake Sibaya, Lake Mzingazi; two fresh inland lakes (hereafter Fresh Inland Lakes, FIL) i.e., Lake Banagher fresh and Lake Tevrede Se Pan; and two inland salt lakes (hereafter Salt Inland Lakes, SIL) i.e., Lake Banagher salt and Lake Chrissiesmeer, all inland lakes are situated in Mpumalanga province, together with other Pans making up the Mpumalanga Lake District of South Africa. The study sites were categorized based on their geographical position i.e., coastal vs inland and physico-chemical characteristics i.e., the presence and absence of aquatic vegetation, dominate substrate, salinity and different physico-chemical concentration i.e., Temperature, Dissolved Oxygen. Aquatic macroinvertebrates were collected from four littoral zone sites (< 1-meter depth) around each lake, whereas phytoplankton samples were collected from four water column sites (> 5-meters depth) and (0.5-meter depth) from the water surface at each lake during summer and winter season. The results were consistent with our hypothesis that both phytoplankton and aquatic macroinvertebrate species composition were influenced by physico-chemical parameters and that the differences in salinity concentration and aquatic vegetation between CL, FIL, and SIL were the driving factors for phytoplankton and aquatic macroinvertebrate species composition. In summary, one hundred and twenty-two phytoplankton taxa were collected and identified during this study, belonging to seven Phyla which included Chlorophyta, Bacillariophyta, Cyanophyta, Chrysophyta, Dinophyta, Euglenophyta, and Cryptophyta. The most abundant phytoplankton groups were Bacillariophyta and Chlorophyta. Phytoplankton relative taxa abundance, Pielou’s evenness, taxa richness, and Shannon diversity were significantly different between lake types. Aquatic macroinvertebrates, on the other hand, summed up to 10 orders, 67 families, and 80 taxa. The most abundant group were the order Coleoptera, Hemiptera, Odonata, and Gastropoda. Aquatic macroinvertebrate relative taxa abundance, taxa richness, and Shannon diversity were also significantly different between lake types. Aquatic macroinvertebrate relative taxa abundance, Pielous evenness, and Shannon diversity index were not significant between seasons, and only taxa richness was significant. Canonical analysis of principal coordinates (CAP) results further showed unique and distinct phytoplankton and aquatic macroinvertebrates community composition between lake types. The present study provides baseline biodiversity inventory (or species list) for important lake ecosystems biological indicators i.e., phytoplankton and aquatic macroinvertebrates and species composition in relation to lake type for six freshwater lakes in South Africa. Furthermore, the study provides empirical evidence that will inform policy and the development of management strategies for freshwater lakes in South Africa which is currently missing. The current study will also contribute to the next National Biodiversity Assessment Report (2024), concerning the freshwater lakes biological data deficiency noted in the previous NBA (2018) report. The study will also fill up the gaps to better understand species composition in lake systems and how they function which is currently limited. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Nkibi, Esethu
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424435 , vital:72153
- Description: Freshwater lakes are generally defined as permanent natural standing water bodies, with some of them having a direct and indirect connection with groundwater, rivers, and the ocean. Freshwater lakes provide essential socio-economic and ecological goods and services including recreation, aesthetic, support aquatic biodiversity, food in a form of fisheries and water for domestic use. Given their critical role in sustainability in providing socio-economic services, freshwater lakes are among the most threatened ecosystems globally due to intense human impacts over the last decades. South Africa has limited freshwater lakes, which according to the National Biodiversity Assessment (NBA 2018), we know little about their current biology except historic aquatic biodiversity studies conducted in the early 1940s. There are no management strategies in place to protect and conserve freshwater lake biodiversity and important ecosystem services. This thesis aims to: (1) produce a biodiversity inventory of phytoplankton and aquatic macroinvertebrate species and, (2) investigate important environmental drivers responsible for phytoplankton and aquatic macroinvertebrate species composition from six South African freshwater lakes. It was hypothesized that the three lake types will show different phytoplankton and aquatic macroinvertebrates species composition attributed by the geographical region (coastal and inland lake) and related physico-chemical parameters. Study sites consisted of two Northern KwaZulu-Natal coastal lakes (hereafter Coastal Lakes, CL) i.e., Lake Sibaya, Lake Mzingazi; two fresh inland lakes (hereafter Fresh Inland Lakes, FIL) i.e., Lake Banagher fresh and Lake Tevrede Se Pan; and two inland salt lakes (hereafter Salt Inland Lakes, SIL) i.e., Lake Banagher salt and Lake Chrissiesmeer, all inland lakes are situated in Mpumalanga province, together with other Pans making up the Mpumalanga Lake District of South Africa. The study sites were categorized based on their geographical position i.e., coastal vs inland and physico-chemical characteristics i.e., the presence and absence of aquatic vegetation, dominate substrate, salinity and different physico-chemical concentration i.e., Temperature, Dissolved Oxygen. Aquatic macroinvertebrates were collected from four littoral zone sites (< 1-meter depth) around each lake, whereas phytoplankton samples were collected from four water column sites (> 5-meters depth) and (0.5-meter depth) from the water surface at each lake during summer and winter season. The results were consistent with our hypothesis that both phytoplankton and aquatic macroinvertebrate species composition were influenced by physico-chemical parameters and that the differences in salinity concentration and aquatic vegetation between CL, FIL, and SIL were the driving factors for phytoplankton and aquatic macroinvertebrate species composition. In summary, one hundred and twenty-two phytoplankton taxa were collected and identified during this study, belonging to seven Phyla which included Chlorophyta, Bacillariophyta, Cyanophyta, Chrysophyta, Dinophyta, Euglenophyta, and Cryptophyta. The most abundant phytoplankton groups were Bacillariophyta and Chlorophyta. Phytoplankton relative taxa abundance, Pielou’s evenness, taxa richness, and Shannon diversity were significantly different between lake types. Aquatic macroinvertebrates, on the other hand, summed up to 10 orders, 67 families, and 80 taxa. The most abundant group were the order Coleoptera, Hemiptera, Odonata, and Gastropoda. Aquatic macroinvertebrate relative taxa abundance, taxa richness, and Shannon diversity were also significantly different between lake types. Aquatic macroinvertebrate relative taxa abundance, Pielous evenness, and Shannon diversity index were not significant between seasons, and only taxa richness was significant. Canonical analysis of principal coordinates (CAP) results further showed unique and distinct phytoplankton and aquatic macroinvertebrates community composition between lake types. The present study provides baseline biodiversity inventory (or species list) for important lake ecosystems biological indicators i.e., phytoplankton and aquatic macroinvertebrates and species composition in relation to lake type for six freshwater lakes in South Africa. Furthermore, the study provides empirical evidence that will inform policy and the development of management strategies for freshwater lakes in South Africa which is currently missing. The current study will also contribute to the next National Biodiversity Assessment Report (2024), concerning the freshwater lakes biological data deficiency noted in the previous NBA (2018) report. The study will also fill up the gaps to better understand species composition in lake systems and how they function which is currently limited. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
Quantifying the training demands of an amateur women’s Rugby union team using Global Positioning System
- Authors: Mbane, Nomabhelu
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424289 , vital:72140
- Description: Rugby union is a dynamic sport that has grown to not only be played by men but by women too. The professionalisation of the sport that happened in 1995 developed the game immeasurably including the focus given to its scientific research. This is important as literature on the demands of the game has become vital in improving the performance of Rugby union players (Deutch et al., 1998; Kay and Gill, 2004; Kruger, 2012). Scientific evidence-based data on the physical and physiological demands is imperative in the planning and setting up of training regimes (Deutch et al., 1998; Kay and Gill, 2004; Kruger, 2012). Unfortunately, the growth in the participation of women’s Rugby union has not been matched with scientific evidence-based literature that seeks to improve the performance of this population of players. Therefore, due to the unavailability of match-play during the COVID-19 outbreak, this study aimed to quantify the physical and physiological demands of training sessions of amateur women’s Rugby union players from the Sarah Baartman District, South Africa using Global Positioning System (GPS). The training’ data collected was compared to previous literature, including studies that also focused on match-play. Furthermore, players were categorized into forwards and backs, allowing for the comparison between the two playing categories. An exploratory, descriptive, observational, and comparative research design was used for the current study. The physical and physiological demands of eighteen women Rugby union players (eight forwards and ten backs) aged between 18 – 36 years old were assessed during training (for a total of nine sessions). To inform the participants’ characteristics, the players’ demographic, and anthropometric characteristics (age, stature, and body mass) were obtained. Using GPS and Zephyr technology the players’ training physical (time spent in speed zones, maximum speed, total distance travelled, number of impacts in the various impact zones) and physiological (heart rate) demands were explored. Statistical analysis methods including descriptive, independent t-test, one-way and two-way ANOVA tests were employed to analyse the data and evaluate the differences between forwards and backs. The mean age and stature for all players was 25,44±5,6 years and 1,60±0,06 m respectively, with no significant differences found between backs and forwards. With regards to body mass, forwards weighed 82,0±9,4 kg while backs weighed significantly lighter at 58,0±5,8 kg. Significant differences (p < 0,05) were found for all players in the time spent in speed zones and the number of impacts in impact zones. When all forwards’ and backs’ physical and physiological demands were compared the results showed no significant differences. The average time spent in all six speed zones combined was 11,41 and 11,62 mins for forwards and backs, respectively. The maximum speeds reached by forwards (21,35±5,72 km/h) and backs (22,85±3,88 km/h) were similar. All players combined travelled an average total distance of 2,14±0,76 km. The total number of impacts in all six impact zones, totalled 116 impacts for forwards and 97 for backs. Heart rate responses recorded for forwards and backs were 139±15 bpm and 134±13 bpm. Based on the findings of this study, the training intensity of amateur women’s Rugby union was lower than the demands experienced in the training and match-play of previous research. It was also observed that there was no specificity with regards to the training programs allocated between forwards and backs of this study. Further research on amateur women’s Rugby union is required to characterise training and match-play demands of these players. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mbane, Nomabhelu
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424289 , vital:72140
- Description: Rugby union is a dynamic sport that has grown to not only be played by men but by women too. The professionalisation of the sport that happened in 1995 developed the game immeasurably including the focus given to its scientific research. This is important as literature on the demands of the game has become vital in improving the performance of Rugby union players (Deutch et al., 1998; Kay and Gill, 2004; Kruger, 2012). Scientific evidence-based data on the physical and physiological demands is imperative in the planning and setting up of training regimes (Deutch et al., 1998; Kay and Gill, 2004; Kruger, 2012). Unfortunately, the growth in the participation of women’s Rugby union has not been matched with scientific evidence-based literature that seeks to improve the performance of this population of players. Therefore, due to the unavailability of match-play during the COVID-19 outbreak, this study aimed to quantify the physical and physiological demands of training sessions of amateur women’s Rugby union players from the Sarah Baartman District, South Africa using Global Positioning System (GPS). The training’ data collected was compared to previous literature, including studies that also focused on match-play. Furthermore, players were categorized into forwards and backs, allowing for the comparison between the two playing categories. An exploratory, descriptive, observational, and comparative research design was used for the current study. The physical and physiological demands of eighteen women Rugby union players (eight forwards and ten backs) aged between 18 – 36 years old were assessed during training (for a total of nine sessions). To inform the participants’ characteristics, the players’ demographic, and anthropometric characteristics (age, stature, and body mass) were obtained. Using GPS and Zephyr technology the players’ training physical (time spent in speed zones, maximum speed, total distance travelled, number of impacts in the various impact zones) and physiological (heart rate) demands were explored. Statistical analysis methods including descriptive, independent t-test, one-way and two-way ANOVA tests were employed to analyse the data and evaluate the differences between forwards and backs. The mean age and stature for all players was 25,44±5,6 years and 1,60±0,06 m respectively, with no significant differences found between backs and forwards. With regards to body mass, forwards weighed 82,0±9,4 kg while backs weighed significantly lighter at 58,0±5,8 kg. Significant differences (p < 0,05) were found for all players in the time spent in speed zones and the number of impacts in impact zones. When all forwards’ and backs’ physical and physiological demands were compared the results showed no significant differences. The average time spent in all six speed zones combined was 11,41 and 11,62 mins for forwards and backs, respectively. The maximum speeds reached by forwards (21,35±5,72 km/h) and backs (22,85±3,88 km/h) were similar. All players combined travelled an average total distance of 2,14±0,76 km. The total number of impacts in all six impact zones, totalled 116 impacts for forwards and 97 for backs. Heart rate responses recorded for forwards and backs were 139±15 bpm and 134±13 bpm. Based on the findings of this study, the training intensity of amateur women’s Rugby union was lower than the demands experienced in the training and match-play of previous research. It was also observed that there was no specificity with regards to the training programs allocated between forwards and backs of this study. Further research on amateur women’s Rugby union is required to characterise training and match-play demands of these players. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2023
- Full Text:
- Date Issued: 2023-10-13
Quantifying the work demands of municipal waste workers to determine physical workload and perception
- Authors: Mamabolo, Lerato
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424267 , vital:72138
- Description: Objective: This study aimed to quantify physical and perceptual workloads through the nature of the work demands of municipal waste workers. Waste workers investigated were waste collectors, street sweepers [or public cleansers], drivers and mechanics. Methods: 154 City of Tshwane municipal waste workers volunteered to participate in the study. Observation-based tools were used to measure physical workload namely, the RAMP 1 and 2, REBA and RULA, and the hand-held dynamometer was used for pushing and pulling tasks. Subjective perceptual questionnaires were used to measure Perceptual load namely the NASA TLX and the QWIQ. Results: Differences in physical workload were evident between the occupation groups. Round bin collection was the waste collection type pertaining to the highest work-related risk of musculoskeletal development. Public cleansers and flatbed truck collectors' results displayed lower task-related risks associated in relation to the other occupations. Significant differences were found between the groups, particularly between waste collectors and drivers [had high workload outputs] in relation to public cleansers [low workload] for both perceptual workload tools. A significant difference was found in the mental and physical demands, as well as the organisational constraints and quantitative workloads. Mechanics showed no significant differences between groups but had high levels of frustration. Conclusion: A relationship between physical and perceived workload intensity is evident. development of musculoskeletal diseases and injury shall incur if measures are not reinstated. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mamabolo, Lerato
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424267 , vital:72138
- Description: Objective: This study aimed to quantify physical and perceptual workloads through the nature of the work demands of municipal waste workers. Waste workers investigated were waste collectors, street sweepers [or public cleansers], drivers and mechanics. Methods: 154 City of Tshwane municipal waste workers volunteered to participate in the study. Observation-based tools were used to measure physical workload namely, the RAMP 1 and 2, REBA and RULA, and the hand-held dynamometer was used for pushing and pulling tasks. Subjective perceptual questionnaires were used to measure Perceptual load namely the NASA TLX and the QWIQ. Results: Differences in physical workload were evident between the occupation groups. Round bin collection was the waste collection type pertaining to the highest work-related risk of musculoskeletal development. Public cleansers and flatbed truck collectors' results displayed lower task-related risks associated in relation to the other occupations. Significant differences were found between the groups, particularly between waste collectors and drivers [had high workload outputs] in relation to public cleansers [low workload] for both perceptual workload tools. A significant difference was found in the mental and physical demands, as well as the organisational constraints and quantitative workloads. Mechanics showed no significant differences between groups but had high levels of frustration. Conclusion: A relationship between physical and perceived workload intensity is evident. development of musculoskeletal diseases and injury shall incur if measures are not reinstated. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 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
Remote sensing as a monitoring solution for water hyacinth (Pontederia crassipes) in the context of the biological control programme at Hartbeespoort Dam
- Authors: Kinsler, David Louis
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424599 , vital:72167
- Description: Water hyacinth (Pontederia crassipes (C.Mart.) Solms (Pontederiaceae)) is a significant aquatic weed both globally and in South Africa. Despite notable success with biological control of other invasive macrophytes, the plant remains as a problematic weed in many aquatic systems in South Africa, particularly due to the eutrophic status of many of its water systems, as well as the plant’s tolerance to cooler climatic conditions than most of its existing biological control agents. Hartbeespoort Dam, located about 30 kilometres west of Pretoria, South Africa, has been infamously infested with water hyacinth for decades, which impacts the important socioeconomic utility of the dam and functioning of natural ecological processes in the system. The dam has a long history of efforts to control water hyacinth, which include widespread herbicidal spray, mechanical removal and classical biological control programmes since the early 1990s - mostly with limited or short-lived success. However, after the introduction of a new, cold-tolerant biological control agent, Megamelus scutellaris Berg (Hemiptera: Delphacidae) in 2018 with an inundative release strategy, the water hyacinth dropped significantly from a maximum cover of about 45 percent (819 hectares) down to less than two percent (40 hectares) over a three-month period (November 2019 – January 2020). This was significant, as it marked the first successful biological control of water hyacinth in a eutrophic, temperate system in South Africa. However, due to the scale of Hartbeespoort Dam (1820 hectares) and the high spatiotemporal variation of the floating mats across time and space, quantifying and monitoring these rapid changes has proved difficult. In response to this problem, this thesis proposed a remote sensing solution to address the need for accurate, timely and readily accessible monitoring data of the water hyacinth population on the dam. Leveraging the temporally frequent (< 5 days revisit time) Sentinel-2 multispectral satellite data, as well as the powerful cloud-computing resources of Google Earth Engine, this thesis developed and deployed a relatively simple and robust index-based decision tree classification method to demonstrate the value of these technologies as an effective monitoring and analysis tool for monitoring large macrophyte infestations. To this end, several challenges had to be overcome in order to produce easily accessible data that was accurate and reliable. For example, due to the size of the Sentinel-2 Level-1C image dataset from August 2015 to March 2021 (n = 654), an automated process of filtering out clouded images was required. Additionally, the co-presence of algal and cyanobacterial blooms necessitated the development of a novel index, coined the Algae Resistant Macrophyte Index (ARMI), to deal with the challenges of accurate macrophyte detection. The high spatiotemporal variability of the floating mats meant that a typical, location-based confusion matrix as a means of assessing the accuracy of the decision tree classifier required a different approach which compared the total classified areas with higher resolution images. This thesis aims to demonstrate the utility of remote sensing tools to provide effective monitoring information to managers, researchers and other stakeholders. There is scope to expand to more areas in South Africa and beyond and may prove an invaluable tool to augment and support on-going and future macrophyte monitoring programmes. , Thesis (MSc) -- Faculty of Science, Geography, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Kinsler, David Louis
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424599 , vital:72167
- Description: Water hyacinth (Pontederia crassipes (C.Mart.) Solms (Pontederiaceae)) is a significant aquatic weed both globally and in South Africa. Despite notable success with biological control of other invasive macrophytes, the plant remains as a problematic weed in many aquatic systems in South Africa, particularly due to the eutrophic status of many of its water systems, as well as the plant’s tolerance to cooler climatic conditions than most of its existing biological control agents. Hartbeespoort Dam, located about 30 kilometres west of Pretoria, South Africa, has been infamously infested with water hyacinth for decades, which impacts the important socioeconomic utility of the dam and functioning of natural ecological processes in the system. The dam has a long history of efforts to control water hyacinth, which include widespread herbicidal spray, mechanical removal and classical biological control programmes since the early 1990s - mostly with limited or short-lived success. However, after the introduction of a new, cold-tolerant biological control agent, Megamelus scutellaris Berg (Hemiptera: Delphacidae) in 2018 with an inundative release strategy, the water hyacinth dropped significantly from a maximum cover of about 45 percent (819 hectares) down to less than two percent (40 hectares) over a three-month period (November 2019 – January 2020). This was significant, as it marked the first successful biological control of water hyacinth in a eutrophic, temperate system in South Africa. However, due to the scale of Hartbeespoort Dam (1820 hectares) and the high spatiotemporal variation of the floating mats across time and space, quantifying and monitoring these rapid changes has proved difficult. In response to this problem, this thesis proposed a remote sensing solution to address the need for accurate, timely and readily accessible monitoring data of the water hyacinth population on the dam. Leveraging the temporally frequent (< 5 days revisit time) Sentinel-2 multispectral satellite data, as well as the powerful cloud-computing resources of Google Earth Engine, this thesis developed and deployed a relatively simple and robust index-based decision tree classification method to demonstrate the value of these technologies as an effective monitoring and analysis tool for monitoring large macrophyte infestations. To this end, several challenges had to be overcome in order to produce easily accessible data that was accurate and reliable. For example, due to the size of the Sentinel-2 Level-1C image dataset from August 2015 to March 2021 (n = 654), an automated process of filtering out clouded images was required. Additionally, the co-presence of algal and cyanobacterial blooms necessitated the development of a novel index, coined the Algae Resistant Macrophyte Index (ARMI), to deal with the challenges of accurate macrophyte detection. The high spatiotemporal variability of the floating mats meant that a typical, location-based confusion matrix as a means of assessing the accuracy of the decision tree classifier required a different approach which compared the total classified areas with higher resolution images. This thesis aims to demonstrate the utility of remote sensing tools to provide effective monitoring information to managers, researchers and other stakeholders. There is scope to expand to more areas in South Africa and beyond and may prove an invaluable tool to augment and support on-going and future macrophyte monitoring programmes. , 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 application of statistical classification to predict sovereign default
- Authors: Vele, Rendani
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424563 , vital:72164
- Description: When considering sovereign loans, it is imperative for a financial institution to have a good understanding of the sovereign they are transacting with. Defaults can occur if proper evaluation steps are not considered. To aid in the prediction of potential sovereign defaults, financial institutions, together with grading companies, quantify the risk associated with issuing a loan to a sovereign by developing sovereign default early warning systems (EWS). Various classification models are considered in this study to develop sovereign default EWS. These models are the binary logit, probit, Bayesian additive regression trees, and artificial neural networks. This study investigates the predictive performance of the various classification techniques. Sovereign information is not readily available, so missing data techniques are considered in order to counter the data availability issue. Sovereign defaults are rare, which results in an imbalance in the distribution of the binary dependent variable. To assess data sets with such characteristics, metrics for imbalanced data are considered for model performance comparison. From the findings, the Bayesian additive regression technique generated better results than the other techniques when considering a basic data analysis. Moreover when cross-validation was considered, the neural network technique performed best. In addition, regional models had better results than the global model when considering model predictive capability. The significance of this study is to develop sovereign default prediction models using various classification techniques focused on enhancing previous literature and analysis through the application of Bayesian additive regression trees. , Thesis (MSc) -- Faculty of Science, Statistics, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Vele, Rendani
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424563 , vital:72164
- Description: When considering sovereign loans, it is imperative for a financial institution to have a good understanding of the sovereign they are transacting with. Defaults can occur if proper evaluation steps are not considered. To aid in the prediction of potential sovereign defaults, financial institutions, together with grading companies, quantify the risk associated with issuing a loan to a sovereign by developing sovereign default early warning systems (EWS). Various classification models are considered in this study to develop sovereign default EWS. These models are the binary logit, probit, Bayesian additive regression trees, and artificial neural networks. This study investigates the predictive performance of the various classification techniques. Sovereign information is not readily available, so missing data techniques are considered in order to counter the data availability issue. Sovereign defaults are rare, which results in an imbalance in the distribution of the binary dependent variable. To assess data sets with such characteristics, metrics for imbalanced data are considered for model performance comparison. From the findings, the Bayesian additive regression technique generated better results than the other techniques when considering a basic data analysis. Moreover when cross-validation was considered, the neural network technique performed best. In addition, regional models had better results than the global model when considering model predictive capability. The significance of this study is to develop sovereign default prediction models using various classification techniques focused on enhancing previous literature and analysis through the application of Bayesian additive regression trees. , Thesis (MSc) -- Faculty of Science, Statistics, 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 dissipation of marital assets pending a divorce order in South Africa: a proposal for reform
- Mahlangu, Busisiwe Hlophane Maria
- Authors: Mahlangu, Busisiwe Hlophane Maria
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424130 , vital:72126
- Description: Dissipation of marital assets takes place where one spouses uses the marital assets with the intention to frustrate the equitable distribution at the dissolution of marriage. This kind of behaviour usually occurs when one spouse anticipates a divorce or when the final divorce order is pending. In this context then, this thesis aims to critically analyse the effectiveness of the legal remedies available to spouses who are negatively affected by the dissipation of marital assets in marriage in community of property and marriage out of community of property with accrual. In this thesis the question is asked: does the current law adequately protect one spouse from another spouse unfairly hiding or dissipating assets from their estate to prevent the equitable distribution of these assets to the other spouse on divorce? In order to answer this question, this thesis proceeds by examining each of the remedies in detail, looking specifically at the statutory remedies set out in the Matrimonial Property Act 88 of 1984, specifically those contained in ss 8, 15 and 20 of that Act. It also considers remedies found in the common law. Ultimately, the study finds that these remedies do not provide adequate protection to spouses affected by the dissipation of marital assets and looks at the particular reasons for this finding. The study then concludes by proposing reforms to provide better protection to affected spouses. These legal reforms include: amending the legislative framework, changing the determinative date of the accrual, legislating a requirement for full disclosure of assets in terms s 8(1) of the Matrimonial Property Act and, finally, advocating for a flexible interpretation of the requirements of s 20 of the Matrimonial Property Act and the common law anti-dissipation remedy. , Thesis (LLM) -- Faculty of Law, Law, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mahlangu, Busisiwe Hlophane Maria
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424130 , vital:72126
- Description: Dissipation of marital assets takes place where one spouses uses the marital assets with the intention to frustrate the equitable distribution at the dissolution of marriage. This kind of behaviour usually occurs when one spouse anticipates a divorce or when the final divorce order is pending. In this context then, this thesis aims to critically analyse the effectiveness of the legal remedies available to spouses who are negatively affected by the dissipation of marital assets in marriage in community of property and marriage out of community of property with accrual. In this thesis the question is asked: does the current law adequately protect one spouse from another spouse unfairly hiding or dissipating assets from their estate to prevent the equitable distribution of these assets to the other spouse on divorce? In order to answer this question, this thesis proceeds by examining each of the remedies in detail, looking specifically at the statutory remedies set out in the Matrimonial Property Act 88 of 1984, specifically those contained in ss 8, 15 and 20 of that Act. It also considers remedies found in the common law. Ultimately, the study finds that these remedies do not provide adequate protection to spouses affected by the dissipation of marital assets and looks at the particular reasons for this finding. The study then concludes by proposing reforms to provide better protection to affected spouses. These legal reforms include: amending the legislative framework, changing the determinative date of the accrual, legislating a requirement for full disclosure of assets in terms s 8(1) of the Matrimonial Property Act and, finally, advocating for a flexible interpretation of the requirements of s 20 of the Matrimonial Property Act and the common law anti-dissipation remedy. , Thesis (LLM) -- Faculty of Law, Law, 2023
- Full Text:
- Date Issued: 2023-10-13
The effectiveness of prolonged exposure therapy for the treatment of PTSD and suicide ideation: a case study
- Authors: Mhlane, Zuziwe Gloria
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424997 , vital:72200
- Description: Post-Traumatic Stress Disorder (PTSD) is regarded as a public health burden in South Africa (SA) (Atwoli et al., 2013; Kagee, Bantjies & Saal 2017; Koenen et al.; 2017; Williams et al., 2007). According to McGowan & Kagee (2013), young adults in SA are a high-risk group of trauma. Exposure to trauma is also associated to comorbid conditions such as depression, anxiety suicidal ideation (SI) experienced by a large population (Bantjes, McGowan, Kagee & Steel, 2016). Prolonged Exposure (PE) is empirically supported and evaluated trauma therapy for PTSD (Foa, Hembree, & Rothbaum, 2007). However, there has been limited to no studies conducted to evaluate the effectiveness of PE in SA. Therefore, this study investigated whether PE is effective treatment for PTSD symptom reduction and suicide ideation in South Africa. Three participants were recruited from Focus on the Family SA (FOTF SA SA) through purposive sampling, and single-case experimental design (SCED) was utilised. PE was implemented online through zoom for 6 sessions on each client. At baseline, all the participants met the criteria for PTSD as per the Post-traumatic stress disorder symptom scale interview for DSM-5 (PSSI-5): Participant 1 (PSSI-5 - 63), Participant 2 (PSSI-5 - 53), Participant 3 (PSSI-5 - 63) and the clinical cut off score is 23. Furthermore, all participants were screened for suicide ideation (SI) using the Beck Suicide Inventory (BSI). All participants’ BSI score ranges were mild to moderate. Participants were also screened for depression using the Beck Depression Inventory second edition (BDI-II) and anxiety using the Beck Anxiety Inventory (BAI). The score ranges for both BDI-II and BAI were moderate to severe. The Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) was also used to assess general psychological distress. The CORE-OM scores for all the participants for trauma, depression and anxiety were severe. However, the risk to self/SI for all the participants was minimal. During the intervention phase, all the participants scores showed a downtrend of PTSD symptomology, as per the Post-traumatic Stress Disorder Checklist for DSM-5 (PCL-5). The PCL-5 scores went down from PCL-5 score of 58 to final session PCL-5 score of 3. The clinical cut off score is 31-33. They were also screened using the BSI, BDI and BAI and the score ranges were mild. The CORE-OM scores for trauma, anxiety, depression, and risk to self/SI were also minimal. Overall, the preliminary result of this study supports the notion that adults with symptoms of PTSD and SI had improved at the end of a brief 6-session PE intervention. The comorbid depression also showed a downtrend. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mhlane, Zuziwe Gloria
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424997 , vital:72200
- Description: Post-Traumatic Stress Disorder (PTSD) is regarded as a public health burden in South Africa (SA) (Atwoli et al., 2013; Kagee, Bantjies & Saal 2017; Koenen et al.; 2017; Williams et al., 2007). According to McGowan & Kagee (2013), young adults in SA are a high-risk group of trauma. Exposure to trauma is also associated to comorbid conditions such as depression, anxiety suicidal ideation (SI) experienced by a large population (Bantjes, McGowan, Kagee & Steel, 2016). Prolonged Exposure (PE) is empirically supported and evaluated trauma therapy for PTSD (Foa, Hembree, & Rothbaum, 2007). However, there has been limited to no studies conducted to evaluate the effectiveness of PE in SA. Therefore, this study investigated whether PE is effective treatment for PTSD symptom reduction and suicide ideation in South Africa. Three participants were recruited from Focus on the Family SA (FOTF SA SA) through purposive sampling, and single-case experimental design (SCED) was utilised. PE was implemented online through zoom for 6 sessions on each client. At baseline, all the participants met the criteria for PTSD as per the Post-traumatic stress disorder symptom scale interview for DSM-5 (PSSI-5): Participant 1 (PSSI-5 - 63), Participant 2 (PSSI-5 - 53), Participant 3 (PSSI-5 - 63) and the clinical cut off score is 23. Furthermore, all participants were screened for suicide ideation (SI) using the Beck Suicide Inventory (BSI). All participants’ BSI score ranges were mild to moderate. Participants were also screened for depression using the Beck Depression Inventory second edition (BDI-II) and anxiety using the Beck Anxiety Inventory (BAI). The score ranges for both BDI-II and BAI were moderate to severe. The Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) was also used to assess general psychological distress. The CORE-OM scores for all the participants for trauma, depression and anxiety were severe. However, the risk to self/SI for all the participants was minimal. During the intervention phase, all the participants scores showed a downtrend of PTSD symptomology, as per the Post-traumatic Stress Disorder Checklist for DSM-5 (PCL-5). The PCL-5 scores went down from PCL-5 score of 58 to final session PCL-5 score of 3. The clinical cut off score is 31-33. They were also screened using the BSI, BDI and BAI and the score ranges were mild. The CORE-OM scores for trauma, anxiety, depression, and risk to self/SI were also minimal. Overall, the preliminary result of this study supports the notion that adults with symptoms of PTSD and SI had improved at the end of a brief 6-session PE intervention. The comorbid depression also showed a downtrend. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-10-13
The effects of exploitation on the activity of Chrysoblephus laticeps in a thermally variable environment
- Authors: Mlotshwa, Nonhle Thubelihle
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424346 , vital:72145
- Description: Embargoed. Expected release date 2025. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mlotshwa, Nonhle Thubelihle
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424346 , vital:72145
- Description: Embargoed. Expected release date 2025. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2023
- Full Text:
- Date Issued: 2023-10-13