Negotiating marginalisation: A socio-economic history of the Kalanga of Mangwe, Zimbabwe, 1940-2015
- Authors: Nyathi, Innocent
- Date: 2022-10-14
- Subjects: Marginalisation , Kalanga (African people) Race identity Zimbabwe , Ethnicity Zimbabwe , Zimbabwe Economic conditions , Zimbabwe Social conditions , Kalanga language (Botswana and Zimbabwe)
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/408705 , vital:70518 , DOI 10.21504/10962/408705
- Description: The thesis explores the relationship between ethnicity, marginalisation, and survival mechanisms amongst the Kalanga people of Mangwe (southwestern Zimbabwe) from the 1940s up until the turn of the 21st century. The study showed how the Kalanga of Mangwe have used ethnicity as a concept to not only claim access to resources but also develop alternative survival strategies that help them seek to navigate their experiences of marginalisation by both the state and the hegemonic position of the Ndebele who dominate the region politically and linguistically. Using evidence from activities such as cross border migration and the mopane economy, I showed how the Kalanga express their displeasure at being dominated through engagement, as was shown in their attempt to fight for their language, for example in the 1940s through regionalised Kalanga organisations as the Kalanga Language and Cultural Development Society (KLCDS), to disengagement such as migration and illegal informal cross border trade. Using ‘conviviality’ and ‘the everyday’, as well as borrowing from the Race Relations Theory (RRT) of Robert Ezra Park as theoretical underpinnings, I demonstrated how amongst the Kalanga of Mangwe ethnic identity can lead to competition for resources, which in turn leads to marginalisation and discrimination which influences their social, political and economic choices that may in turn reinforce ethnic identity in a cycle like scenario. Everyday economic and social activities amongst the Kalanga of Mangwe that appear mundane and ordinary to an uninterested observer, help shape the everyday discourse of the Kalanga as they navigate marginalisation. , Thesis (PhD) -- Faculty of Humanities, History, 2022
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- Date Issued: 2022-10-14
An African language in the public sphere – the use of isiZulu on Yilungelo Lakho online platforms
- Authors: Bramdeo, Aasra
- Date: 2022-10-14
- Subjects: Zulu language , News Web sites South Africa , South African Broadcasting Corporation , Facebook (Firm) , Social media and journalism South Africa , Public sphere South Africa , Mass media and language South Africa , Yilungelo Lakho
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405919 , vital:70219
- Description: The South African Broadcasting Corporation (SABC) is mandated as the public broadcaster to provide news content in all South Africa’s official languages. While this has been a challenge on traditional broadcast platforms, online resources, such as social media pages, present an opportunity for the SABC to support the creation and sharing of content in African languages. With relatively little national news and current affairs content available online in indigenous languages, this study investigates the way that SABC News online offerings in the isiZulu language have the potential to contribute to public debates in terms of Habermas’ concept of a public sphere and its adaptation to the online domain, taking into consideration scholarly critiques of its suitability in the African context. The SABC News Current Affairs programme Yilungelo Lakho serves as a case study to examine the potential for the SABC to share African-language news content online. The programme is broadcast primarily in the Nguni languages, and the online audience on Facebook often choose to respond in isiZulu or other African languages. Semi-structured indepth interviews were conducted with three members of the production team and three contributors to the Facebook page. A textual analysis of Facebook posts across 13 episodes, with a total of 497 comments from 306 online contributors highlights the manner in which online interaction promotes or hampers the inclusion of isiZulu speakers in SABC News and Current Affairs discussions, rational deliberation on the SABC Current Affairs programme, and fragmentation and overlap across different online platforms. While multilingual interactions on the Yilungelo Lakho Facebook page make for complex curation, the findings suggest the need for African language content to support public discussions and point to an opportunity for the public broadcaster to fulfil its mandate. , Thesis (MA) -- Faculty of Humanities, School of Journalism and Media Studies, 2022
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- Date Issued: 2022-10-14
Constraints on Cr-PGE Mineralisation Models: Geochemical and petrological studies in the Middle Group 1 and 3 Chromitites, Western Limb, Bushveld Complex, South Africa
- Authors: Arunachellan, Yogendran
- Date: 2022-10-14
- Subjects: Chromite South Africa Bushveld Complex , Mineralogy South Africa Bushveld Complex , Geochemical surveys South Africa Bushveld Complex
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362730 , vital:65357
- Description: The Bushveld Complex in South Africa has been of interest in various research groups for decades, along with diverse theories regarding its origin, formation, and emplacement. These theories include magma mixing, contamination, and changes in the chamber's ephemeral parameters. Of interest for our current study is the formation of the middle group chromitite layers in the Western Limb. In this research, we aimed to determine the emplacement mechanism of the MG group chromitites by scrutinising the MG 1 and MG 3 layers. In core KD 151, the focus was placed on the MG 3 and MG 1 chromitite layers and their associated silicate rocks; on these regions of the core, time was spent for detailed observations. The differences and similarities of these layers were explored as the study advanced. The objectives were to determine the in-situ or proximal crystallisation of the chromitite by evaluating mineral textures and compositions. This required that we determine the characteristics of the immediate HW (hanging wall) and FW (footwall) to these chromitites, with insights into the relationship that anorthositic zones may offer and examine the PGE profiles of the chromitites in contrasting lithological settings. The sampled borehole was in the Western Limb of the Bushveld Complex; the immediate HW, chromitite layers and FW were divided into sections (2.5 x 5 cm) along selected horizons for a microscale study. The preliminary results of a study on the sub-economic Middle Group (MG) layers within the Critical Zone (CZ), contrasting the MG 1 (Lower CZ) and MG 3 (Upper CZ) chromitite layers of the Rustenburg Layered Suite of the Bushveld Complex, South Africa were analysed. The MG 3 and 1 suites of silicate rocks show disequilibrium textures between the pyroxenes and plagioclase, forming discontinuous olivine rims. These reaction rims are interpreted as products of magmatic aqueous fluid-facilitated reactions with minerals in a sub-solidus state. Deformation of the plagioclase was also noted in MG 1; this fracturing indicates either the transportation of these minerals or compaction by an overlying crystal mush. The MG 3 package of plagioclase, pyroxene and chromite compositions range from An67-78, En71-86 and Cr# of 68-84, respectively. The MG 1 package of plagioclase, pyroxene and chromite compositions are An64-91, En79-88 and Cr# of 70-80, respectively. The Cu/Pd ratio decreases from the base of the FW as it approaches the base of the chromitite, then remains low within the chromitite layer and finally increases upwards in the HW. These trends are observed in both the MG 3 and 1 package, therefore not influenced by the sulphide control. There is a decrease in both IPGE and PPGE upwards as the HW progresses into the chromitite. The FW levels of Ir and Ru increase upwards immediately adjacent to the FW contact, while Pd and Rh concentrations decrease. The whole-rock Mg# indicates a decrease in the MG 3 with a uniform increase in the HW and an erratic upward increase observed in the FW. The chondrite normalised PGE plots show a bell-shaped curve which is evident for the En content of the pyroxenes and the content of plagioclase with the highest values in the chromitite layer itself. The Cr# of the chromite decreases upwards with the highest values along the FW. The Cu/Pd ratio for MG 1 indicates chromitite control rather than sulphide control of the PGE. The whole-rock Mg# decreases in MG 1 with higher uniform values observed in the HW and FW. The geochemical and petrological data from the MG group study revealed that in situ fractional crystallisation seems unlikely as the sole mechanism for their formation in the CZ. A model is suggested in which the migration and transport of a magmatic slurry type suspension with accompanying hydrous fluids would likely have resulted in the emplacement of these chromitite packages along with the PGE mineralisation of the chromitites. , Thesis (MSc) -- Faculty of Science, Geology, 2022
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- Date Issued: 2022-10-14
Puma (Puma concolor) diet and habitat use in south-west New Mexico
- Authors: Bernard, Kelly Monica Tandi
- Date: 2022-10-14
- Subjects: Puma Food New Mexico , Puma Habitat New Mexico , Puma Nutrition New Mexico , Puma Conservation New Mexico , Carnivorous animals New Mexico , Red deer , Elk , Mule deer , Ungulates
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362752 , vital:65359
- Description: The puma (Puma concolor) is a wide-ranging large felid species occupying an extensive geographic range throughout North and South America, and site-specific research on their diet is important for local management. Like other large felids, puma diet may differ between sexes due to size dimorphism, and between seasons due to changes in prey vulnerability and availability. This study assessed the influence of sex and season on puma diet in south-west New Mexico in terms of prey species and prey size categories. Pumas specialised on mule deer and elk throughout the year, and killed a range of other species of different sizes. The diet of the smaller female puma was nested within the diet of males, supporting the size-nested strategy. The effect of puma sex on prey species and size categories was independent of season, and vice versa, and the probability of a female making a medium-sized kill such as mule deer was higher than for males, while the probability of an extra-large kill such as elk was substantially greater for males. The probability of pumas killing either mule deer or elk in each season was similar, and greater than other species categories. Additionally, individual puma strongly influenced all prey species and size categories killed. The results from this study concur with previous findings on the importance of mule deer and elk in puma diet, and suggest that puma predation may also impact a number of other species, particularly smaller herbivores like collared peccary, and mesocarnivores such as skunks. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2022
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- Date Issued: 2022-10-14
“Around Hip Hop” : rethinking and reconstructing urban youth identities in South Africa - a case study of Fingo Village, Makhanda
- Authors: Futshane, Luniko
- Date: 2022-10-14
- Subjects: Hip-hop South Africa Makhanda , Urban youth South Africa Makhanda , Youth development South Africa Makhanda , Social change , Multiculturalism , Black Consciousness Movement of South Africa
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406760 , vital:70305
- Description: The main objective of this thesis is to investigate how conscious hip hop culture is used to reconstruct and influence urban youth identities in South Africa, in the case of Fingo Village, Makhanda. In addition, it aims to understand how the South African conscious hip hop scene, appropriated from the West, can be used to shape the identities of the urban youth, instead of the materialistic commercial/mainstream gangsta rap that is currently dominating popular culture and media today. Kellner’s (1995: 10) multicultural critical approach is appropriate for this thesis, as it “provides a critical multiculturalist politics and media pedagogy that aims to make people sensitive to the relations of power and domination which are encoded in cultural texts, such as those of television and film, or new technologies and media such as Internet, and social networking”. Moreover, in the words of Cvetkovich and Kellner (cited in Dolby, 2010:11), this dissertation “investigates the increasing influence of global popular culture and its possibility to equip the urban youth with new sources of identification”, as well as opportunities for social change. In Makhanda, rappers, community activists, B-Boy crews, graffiti artists, spoken-word poets, photographers, and journalists all assembled in Fingo Village for the social event Around Hip Hop, at the multipurpose Fingo square, between 2011 and 2019. Today, Around Hip Hop is an arts based organization that produces hip hop mixtapes, short documentaries, and educational events aimed at creating a cross-cultural exchange and increasing awareness of South African politics. Around Hip Hop has hosted various events, dialogues, and performances where hip hop is used as a cultural expression, which continuously creates spaces for the urban youth to rethink and reconstruct their identities; not only as artists, but as audience members as well. Events, such as The Return of the Cypher, Intyatyamo Elityeni, and Business beyond Fingo Festival all form part of Around Hip Hop. The Return of the Cypher is an open music event, where rappers, usually gathered in a circular formation with one or more artists performing in the middle, showcase their skills. Semi-structured interviews were conducted with eight local hip hop artists in Makhanda, in order to investigate how conscious hip hop is used to rethink and reconstruct urban youth identities. , Thesis (MA) -- Faculty of Humanities, Sociology, 2022
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- Date Issued: 2022-10-14
The invisible teacher: The teacher envisaged in the Curriculum and Assessment Policy Statement (CAPS) English First Additional Language (EFAL) Further Education and Training (FET) Phase
- Authors: Dowejko, Diane Agnieszka
- Date: 2022-10-14
- Subjects: Educational sociology South Africa , Systemic functional linguistics , Curriculum-based assessment South Africa , Linguistic analysis (Linguistics) , Educational evaluation South Africa
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406714 , vital:70301
- Description: Educational policy documents, which are intended to enlighten teachers about what they should teach and how they should assess learners, contain both language and knowledge. How this knowledge is construed through language may reveal the kind of teacher envisaged by the document, and the assumptions made regarding the dispositions of these educators. There is a plethora of research on the relationship between the Curriculum and Assessment Policy Statement for English First Additional Language in the Further Education and Training Phase (CAPS-EFAL) and its impact on the learner in the classroom, but little evidence of research related to how curriculum documents envisage the teacher, and linguistic research pertaining to CAPS-EFAL. This research aims to use linguistic analysis to discover how the teacher is envisaged in this document, while speaking to the broader subject of the relationship between teacher and curriculum policy. This study adopts a framework which inspects this language using Systemic Functional Linguistics to analyse language in relation to its functions in social contexts, and the instructional knowledge built in CAPS-EFAL through applying elements of Legitimation Code Theory, analysing processes of knowledge production and recontextualisation. An investigation of the language revealed assumptions that the envisaged teacher is one who is already highly trained in aspects of language teaching and classroom methodology and pedagogy. While the analysis also revealed a high level of guidance for the teacher, there was a strong focus on the knowledge within the curriculum, and several assumptions made regarding the teacher’s prior knowledge before encountering or utilising the document. The analysis also revealed that CAPS-EFAL acknowledges that the teacher requires a sound knowledge of technical terminology related to language teaching, as well as general classroom pedagogies and routines. In addition, the document assumes that the disposition of the teacher is one who can make decisions without the need for absolute confirmation or authority from curriculum documentation. Overall, the analysis revealed an élite code in terms of Specialization; CAPS-EFAL is therefore based on the legitimacy of both specialised knowledge and the disposition of the teacher. , Thesis (MA) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2022
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- Date Issued: 2022-10-14
Characterising the sleep wake behaviour of late adolescents living in rural and township areas surrounding Alice in the Eastern Cape of South Africa
- Authors: Dlepu, Phelokazi
- Date: 2022-10-14
- Subjects: Teenagers Sleep South Africa Alice , Rural teenagers South Africa Alice , Sleep-wake cycle
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362808 , vital:65364
- Description: Introduction: School going adolescents have been identified as a group that is at risk of obtaining insufficient sleep due to shortened and irregular sleep, all of which can affect the overall wellbeing of adolescents. While there has been extenstive research on adolescent sleep around the world, research in South Africa has been limited. Of the research performed in this context, most has been conducted in city or urban contexts, but there has been comparatively less research on sleep in adolescents from rural and township areas. Therefore, this study focused on characterising and comparing the sleep-wake behaviour of late adolescents from selected rural and township areas in Alice in the Eastern Cape of South Africa. Methods: An adapted version School Sleep Habits Survey (SSHS) was included in the study and assessed demographic, academic, sleep-wake behaviour, lifestyle, and behavioural information of adolescents from rural and township schools in and around Alice. The survey was distributed physically to all the learners from four co-educational rural and township schools. The responses to the survey were analysed with descriptive and non-parametric inferential statistics, as all data were not normally distributed. Results: A total of 123 learners completed the survey. All the participants were in Grade 12, aged 16 to 26 years (median =18, IQR= 18-19) from rural (n=28) and township (n=95) schools. Seventy-four female and 49 male learners participated in the study. Within the sample, there were also a group of participants who were not adolescents (n=22) whose age ranged between 20 and 26. Reported sleep during both the week and weekend (7hours) was lower than both the recommended duration for adolescents and their own self-reported sleep need of a median of 8 hours and 14 minutes. Bedtimes were significantly earlier on weekdays than weekends. The need to do homework and feeling sleepy were cited as the main reasons for going to sleep during the week and the weekends. Wake times on weekdays and weekends did not differ, with most learners citing being woken up by an alarm clock as the main reason for waking during both weekdays and weekends. Most learners (n=47; 38%) reported walking to get to school, while 41 (33%) relied on public transport to get to school. There were no significant effects of gender or of being rural and township scholars in relation to their sleep variables. Comparisons between non-adolescents and adolescents revealed that non-adolescents reported sleeping longer (7 hours and 30 minutes) compared to adolescents (7 hours) than adolescents did on weekends. As a group, the learners in this sample were morningness-orientated in terms of chronotype, presented with low day time sleepiness, some evidence of sleep-wake behaviour problems and of depressive mood symptoms. Nearly half (n=53; 43%) the group reported napping occasionally on school days. In terms of caffeine consumption, just over half (n=64; 52%) of the learners reported never consuming caffeinated substances such as soda, coffee, or tea. Conclusions: The reported sleep duration of learners in this study was consistent on both the week and weekend but was shorter than the recommended 8-10 hours for late adolescents. While learners in this sample reported early bedtimes, sleep was likely curtailed by the early rise times due to the contextual constraints where scholars had to commute, by either walking or taking public transport, to make the early school start times. There was a high prevalence of sleep disturbances in this sample however, the effects of this (increased daytime sleepiness) were lower which can be attributed to low reported prevalence of caffeine consumption combined with the high prevalence of reported day time napping on school days and weekends. While only a snapshot, the results of this study support previous research that has highlighted the challenges that many adolescents across the globe experience when it comes to obtaining enough sleep. The results of this study highlighted the need for more research to understand the sleep-wake behaviours of learners and their lifestyles more objectively. Given the early starts for many participants in this study, interventions such as delaying school start times may help to improve the amount of sleep that learners get during the week. However, extensive consultations would be needed to ensure that systemic changes that aim to improve sleep of adolescents are applicable for the context of rural and townships areas in South Africa. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2022
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- Date Issued: 2022-10-14
Land degradation and livelihood strategies in rural Zimbabwe: the case of two A1 farms in Shurugwi District
- Authors: Nciizah, Tendai
- Date: 2022-10-14
- Subjects: Land degradation Zimbabwe , Sustainable livelihood , Shurugwi District , Conservation of natural resources Zimbabwe , Land reform Zimbabwe
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/365989 , vital:65808 , https://doi.org/10.21504/10962/365989
- Description: Land degradation is a global phenomenon which is having serious negative consequences for rural livelihoods, which depend quite fundamentally on land and its resources. At the same time, one of the key conditions contributing to land degradation relates to rural livelihood practices, insofar as these practices fail to protect the land. Hence, there sometimes exists a mutually-reinforcing process of decline, in relation to both land vitality and livelihoods vitality over time. This thesis seeks to investigate and understand this complex land-livelihoods process through a case study of two fast track farms in the Shurugwi District of contemporary Zimbabwe. In the year 2000, the Zimbabwean government introduced the fast track land reform programme which fundamentally reconfigured the rural landscape. In particular, it led to the formation of A1 farms (containing small-scale farming units called A1 plots), onto which people were resettled for purposes of enhancing their livelihoods. The case study focuses on two A1 farms in the district, namely, Selukwe Peak and Adare farms. Through a longitudinal study of land and livelihoods on these A1 farms, this study seeks to identify the multi-faceted character of land degradation on the farms, the multi-layered conditions (or causes) facilitating land degradation (specifically, the farm-based livelihood practices) and the effects of this land degradation on these very livelihood practices. This includes a focus on farmers’ understandings of land degradation and how these understandings may or may not condition livelihood practices on the two farms. Of particular importance is the presence of not only agricultural practices, but also high levels of illegal and legal mining on the farms and in the surrounding areas. In pursuing this study, the thesis draws upon the Sustainable Livelihoods Approach alongside Margaret Archer’s morphogenetic sociological perspective. Combined, they provide an intricate understanding of the relevance of both structure and agency to the analysis. A qualitative methodology was used, and this involved a questionnaire survey, in- depth interviews, life histories, focus group discussions and transect walks. The study concludes that the livelihood strategies undertaken by the villagers of Selukwe Peak and Adare farms are key causes of land degradation, as are the land-degrading activities of illegal and legal miners. The A1 villagers are aware that their activities are causing land degradation but they continue these activities because they are pushed by circumstances beyond their control. Hence, both proximate and underlying causes are of some significance in understanding land degradation and livelihoods on the two farms, and their interrelationships. , Thesis (PhD) -- Faculty of Humanities, Sociology, 2022
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- Date Issued: 2022-10-14
Investigating the roles of HOP isoforms in KSHV biology
- Authors: Matandirotya, Lorraine Tariro
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/365257 , vital:65721
- Description: Thesis embargoed. Possible release date set for early 2025. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2022
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- Date Issued: 2022-10-14
Cape Fold Ecoregion fish community ecology and responses to stressors
- Authors: Broom, Casey Jay
- Date: 2022-10-14
- Subjects: Cyprinidae South Africa Western Cape , Freshwater fishes South Africa Western Cape , Cyprinidae Habitat South Africa Western Cape , Food chains (Ecology) , Restoration ecology South Africa Western Cape , Riparian restoration South Africa Western Cape
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/365644 , vital:65772 , DOI https://doi.org/10.21504/10962/365644
- Description: Freshwater fishes are in global decline and fish as a group are the most imperilled of all vertebrates. Freshwater systems are among the most threatened globally, largely owing to their comparatively high species and habitat diversity while occupying a minute fraction of the Earth’s surface. In South Africa, invasion by non-native fishes has had a devastating effect on freshwater systems across the country. Numerous other stressors and anthropogenic impacts continue to impact these systems, including habitat degradation, water abstraction and global change effects. In general, South African freshwater systems are under-studied and there is a lack of baseline biological and ecological studies on many freshwater fish species. The Cape Fold Ecoregion (CFE) of South Africa is a particularly vulnerable region, with many range-restricted species and highly fragmented native fish ranges following high invasion rates. Within the CFE, the Olifants-Doring River System (ODRS) is of primary concern owing to the high endemism and imperilled status of its freshwater fish species. The Rondegat River in the ODRS is of notable conservation value, as it hosts populations of important endemic CFE species. This river is unique, being the site of the first alien fish eradication programme of its kind in South Africa. Thus the Rondegat River, and in particular its imperilled cyprinid assemblage, is used here as a case study of the responses and community dynamics of recovering freshwater fish species. The members of this cyprinid assemblage are Sedercypris calidus, Pseudobarbus phlegethon and Labeobarbus seeberi. Sedercypris calidus and L. seeberi are listed by the International Union for the Conservation of Nature (IUCN) as “Near-Threatened”, while P. phlegethon is listed as “Endangered”. Understanding the dynamics and responses to understudied vulnerable fish communities in the wake of restoration efforts was the overarching goal of this thesis. The first chapter served as a review of current knowledge of the CFE, the Rondegat River, the myriad stressors that have impacted on or are projected to affect this region, and the freshwater fish species on which those stressors act. My first investigations served as an extension of the existing Rondegat River monitoring programme, making use of remote underwater video (RUV) data to assess relative abundance and habitat associations of the focal species (Chapter 2). A relatively limited spatial range of P. phlegethon was established, which was suggested to be a result of relatively highly specialised habitat requirements and sensitivity to disturbance. Sedercypris calidus was confirmed as a relatively more abundant and ubiquitous species across the length of the Rondegat River, sharing much of the lower and middle reaches with L. seeberi. I sought to use experimental trials of functional response, as a proxy for feeding performance, across representative temperatures and relevant prey types, in the spatially overlapping S. calidus and L. seeberi (Chapter 3). Labeobarbus seeberi generally outcompeted S. calidus across temperature treatments and prey types. The ecomorphology and diet of all three species were used to construct trophic profiles, which suggested that there was a high degree of feeding capacity overlap between L. seeberi and S. calidus, while P. phlegethon diverged from the other two species (Chapter 4). Gut content suggested that all three species overlapped broadly in diet. This indicated that the realised trophic niche of these species is similar, despite some morphological specialisation. I then used RUV data to investigate in-situ feeding behaviours, with the aim to disentangle the nuances of community dynamics and mechanisms of coexistence in the cyprinid assemblage (Chapter 5). I found that, despite the higher feeding performance of L. seeberi (Chapter 3) and its overlaps in diet and feeding capacity with S. calidus (Chapter 4), S. calidus is able to mitigate competitive pressures through foraging mode switching and exploitation of allochthonous food inputs. Evidence for further habitat and prey selectivity in Pseudobarbus phlegethon was gathered based on dependence on complex habitats and pool refugia for the majority of its feeding, supporting this species as a headwater specialist; alongside signals of its spatial and habitat use patterns (Chapter 2). While S. calidus and L. seeberi were found to be less habitat-specific than P. phlegethon, caution was noted in the potential for ongoing stressors, such as habitat destruction, loss of river connectivity and global change effects, to impact on the reproductive success of these two species. Stressors affecting the habitats and sensitive invertebrate taxa upon which all three species depend continue to threaten the Rondegat system, highlighting the need to maintain ecosystem integrity through conservation interventions. There remains significant scope to maintain restoration efforts in the Rondegat River and other river systems of the CFE, through direct conservation actions, enhanced community awareness, indigenous riparian vegetation restoration and involvement of local stakeholders in various conservation-centred activities. , Thesis (PhD) -- Faculty of Science, Ichthyology and Fisheries Science, 2022
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- Date Issued: 2022-10-14
Teaching in times of crisis: understanding the uneven effects of the COVID-19 lockdowns on teaching practices in Zimbabwe – a case study of Marondera
- Authors: Nhliziyo, Sarah Mazvita
- Date: 2022-10-14
- Subjects: COVID-19 Pandemic, 2020- Zimbabwe , Lockdown , Social distancing (Public health) and education Zimbabwe , Educational equalization Zimbabwe , COVID-19 Pandemic, 2020- Economic aspects , Teaching Social aspects Zimbabwe
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/408682 , vital:70516
- Description: The COVID-19 pandemic has exposed the fragility of economies in times of a global crisis while simultaneously increasing inequalities between and within countries. The pandemic responses have varied between countries with some being extremely proactive and others being quite reluctant to respond. Though it is largely a health crisis, its impact has far reaching effects that have been felt in many sectors of society including education. Billions of scholars at varying levels were forced out of school abruptly globally and unfortunately some have not been able to return to schools. The differential impact of COVID-19 in education is evident not only at a global level, but national level as well. The primary focus of this research is the impact of COVID-19 on the teaching practices applied in Zimbabwean schools. Zimbabwe, a developing nation in the southern region of Africa, has a long history of a thriving education sector recognised internationally. However, in the wake of the pandemic, the research attempts to understand the experiences of teachers in private and government schools in the hope of showing the dilapidation and unevenness of the sector, across the private-public divide. COVID-19 comes at a time when the country’s economy and healthcare system continue to exhibit signs of struggle and collapse. The research made use of qualitative research methods and in-depth interviews with teachers from public and schools around the town of Marondera. The research concluded that there are wide gaps in the quality of education delivered to students in private and government schools, and that the COVID-19 lockdowns in Zimbabwe not only demonstrate these gaps but also exacerbated them. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2022
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- Date Issued: 2022-10-14
An investigation of language choice on Twitter: the case of isiXhosa-speaking users and the o jewa ke eng? Trend
- Authors: Nkunzi, Zindzi
- Date: 2022-10-14
- Subjects: Twitter , Social media South Africa , Social media and society South Africa , Xhosa language Usage , Mass media and language South Africa , Language choice , Language shift , Language attitude
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406331 , vital:70259
- Description: The study critically examines and discusses language choice on twitter, a social media platform that has a vast number of people from different language groups. This diverse platform allows people to tweet, communicate, and share information online. There are tweets that trend and attract more engagement across different language groups. O jewa ke eng? which translates to ‘what’s bothering you?’ is one of those tweets, and it is communicated in Sesotho. (More discussion about the tweet in the introduction section that follows). According to Eisenstein, O’ Connor, Smith & Xing (2010) & Eisenstein (2016), “the popularity and ubiquity of social media allows access to a wide variety of spontaneous language enabling researchers to study language variation across space and time at large scale”, (Preotiuc-Pietro & Ungar, 2018: 1534). The introduction to the internet and socially mediated platforms such as Twitter and others has changed how information is produced and consumed. Social media allow people to communicate and engage in languages they are comfortable and familiar with. The study discusses language choice at three levels: language choice between isiXhosa verses English; isiXhosa verses other African languages and isiXhosa verses other varieties. The study is pursued with the overarching aim to investigate the possibility of African languages such as isiXhosa being used as dominant languages on social media. Thus, the study explores language use by isiXhosa speaking users on twitter that engaged with the tweet. Moreover, the study investigated why they choose to use one language over the other or multiple languages. To give a broader perspective on the study, language choice, language shift and language attitude are discussed and critically evaluated. Theoretically, the concept of code-switching and code-mixing is used when looking at bilingualism and multilingualism. It is imperative to look at multilingualism because the prevalent use of English is no longer a barrier to communication, social media platforms have created a space where African language users are able to engage in their native languages. Moreover, the study explores the use of standard and non-standard isiXhosa languages. There are varieties of languages such as tsotsitaal, slang and others, and these language varieties are not recognised as standard, used in educational settings and so on. In doing so, language attitude is used as the concept to investigate what propels isiXhosa users to or not to use these language varieties in the online communities. The study is explored with the aim to investigate whether social media either grows and preserves African languages online or these platforms are detrimental to these languages, as the language utilised on them is casual and vague, in terms of both spoken and written speech. , Olu phando luvavanya kwaye luxoxa nzulu ngokhetho lolwimi kuTwitter, ikhasi lonxibelelwano elinenani elikhulu labantu abavela kumaqela eelwimi ezahlukeneyo. Eli khasi labantu abohlukeneyo libavumela ukuba babhale, banxibelelane, kwaye babelane ngolwazi kwi-intanethi. Kukho ii-tweets (imibhalwana emifutshane) ezihamba phambili kwaye zitsala uthethathethwano phakathi kumaqela eelwimi ezahlukeneyo. O jewa ke eng? ethetha ukuthi, ‘ukhathazwa yintoni?’ yenye yezo tweets (yalo mibhalwana mifutshane), kwaye idluliselwe ngesiSuthu. (Ingxoxo engakumbi malunga ne-tweet (nombhalwana omfutshane) ifumaneka kwicandelo lentshayelelo elilandelayo). Ngokutsho kukaEisenstein, O’ Connor, Smith & Xing (2010) kunye noEisenstein (2016), “ukuduma kunye nobuninzi beendaba zoluntu kubangela ezo ndaba ukuba zinwenwele kwiindidi ezininzi zeelwimi nezivumela abaphandi ukuba bafunde ngokwahlukana kolwimi kwindawo kunye nexesha…”, (Preotiuc-Pietro & Ungar, 2008: 1534). Ulwaziso kwi-intanethi kunye namakhasi onxibelelwano oluntu afana ne-Twitter kunye namanye, luyitshintshile indlela ulwazi oluveliswa ngayo kunye nendlela olusetyenziswa ngayo. Amakhasi onxibelelwano oluntu avumela abantu ukuba banxibelelane kwaye bazibandakanye ngeelwimi abakhululekileyo ukuzisebenzisa nabaqhelene nazo Olu phando luxoxa ngokukhethwa kolwimi kumanqanaba amathathu: ukukhethwa kolwimi phakathi kwesiXhosa kunye nesiNgesi, isiXhosa kunye nezinye iilwimi ziseNtu, kwakunye nesiXhosa kunye nezinye iindidi zolwimi. Olu phando luqhutywa ngeyona njongo iphambili yokuphanda ukuba ngaba iilwimi zesiNtu ezifana nesiXhosa zingasetyenziswa njengeelwimi eziphambili kamakhasi onxibelelwano na. Kungoko, uphando luphonononga ukusetyenziswa kolwimi ngabo bantetho isisiXhosa kuTwitter abanxibelelana ne-tweet (nombhalo omfutshane). Olu phando, lukwaphanda ukuba kutheni bekhetha ukusebenzisa ulwimi oluthile kunolunye okanye iilwimi ezininzi. Ukunika umbono ngokuthe gabalala ngolu phando, ukukhethwa kolwimi, utshintsho lolwimi, kunye nesimo sengqondo solwimi ziyaxoxwa kwaye zihlolwa ngokunzulu. Ngokwethiyori, ingqikelelo yokutshintshatshintsha iilwimi kunye nokuxuba iilwimi (ukusebenzisa iilwimi ezahlukeneyo kumgca okanye umbhalo omnye) ziyasetyenziswa xa kujongwa ukusetyenziswa kweelwimi ezimbini kunye neelwimi ezininzi. Kunyanzelekile ukuba kujongwe ukusetyenziswa kweelwimi ezininzi kuba ukuxhaphaka kokusetyenziswa kwesiNgesi akusengomqobo kunxibelelwano, amakhasi onxibelelwano (amaqonga osasazo) oluntu avule indawo apho abasebenzisi beelwimi zesiNtu bakwaziyo ukuthetha ngeelwimi zabo zomthonyama. Ngaphezu koko, olu phando luphonononga ukusetyenziswa kweelwimi zesiXhosa ezisemgangathweni nezingekho mgangathweni. Kukho iintlobo ngeentlobo zeelwimi ezifana neTsotsitaal, ulwimi lwe-slang nezinye, kwaye ezi ntlobo zeelwimi aziqatshelwa njengeelwimi ezisemgangathweni, ezisetyenziswa kumajelo emfundo njalo njalo. Ngokwenza oko, isimo sengqondo solwimi sisetyenziswa njengengcamango yokuphanda ukuba yintoni eyenza abasebenzisi besiXhosa basebenzise okanye bangasebenzisi ezi ntlobo zeelwimi kwi-intanethi. Olu phononongo luphononongwa ngeenjongo zokuphanda apho amaqonga onxibelelwano akhula kwaye agcine khona iilwimi zesiNtu kwi-intanethi okanye lamaqonga onxibelelwano abubungozi kwezilwimi, njengoko ulwimi olusetyenziswa kula maqonga luqhelekile kwaye alucacanga, ngokwentetho ethethwayo nebhaliweyo. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
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- Date Issued: 2022-10-14
Regulation of Oct4 expression during cell stress
- Authors: Samson, William John
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/365712 , vital:65778
- Description: Thesis embargoed. Expected release date early 2025. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2022
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- Date Issued: 2022-10-14
The process of thicket encroachment in semi-arid savanna: community patterns and biotic interactions
- Authors: Nell, Rhys
- Date: 2022-10-14
- Subjects: Scrub encroachment , Savanna ecology , Biotic interaction , Plant nutrients , Plant-water relationships
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/364966 , vital:65666
- Description: Bush encroachment in savannas is widespread in South Africa and is concerning, from both socio-economic and conservation viewpoints, as it affects ecosystem services, functioning and productivity. This phenomenon depends on multiple factors such as history, vegetation, management and environmental conditions, and their interplay. Encroachment into savannas has been relatively well-documented, however understanding of the different roles of tree-tree interactions between species that occur during this process is still limited. This includes the interactions causing spatial patterning, or how interactions and outcomes change over time in terms of encroachment succession from open savanna to closed-canopy thicket. The main objectives of this research are to document thicket establishment in a savanna ecosystem and consider the ecological roles of the key woody species and the abiotic properties of their micro-sites. Determining interactive effects of species co-occurrence is critical to understanding or predicting patterns and changes in biodiversity, nutrient distribution and available water resources. It is also imperative in determining correct and effective land management practices, particularly for reducing bush encroachment and its negative effect on rangelands. All data were collected on Endwell farm, located in the Smaldeel region of the Eastern Cape, South Africa. Endwell farm is a semi-arid savanna with a mean annual rainfall of 730 mm. First, I examine and describe the thicket encroachment process by exploring the associations between species and their size classes in the field. This was done by using plot-based belt transects and looking at changes in species size-class compositions from early to late successional stages. Association rules (market basket) analysis was used to identify the most common species size-class association patterns. The association between the savanna tree Vachellia karroo and the thicket pioneer Scutia myrtina was the most prevalent at all stages, with V. karroo being central to all associations in the first stage of encroachment; during later stages of encroachment, associations shift to incorporating other thicket pioneer species. The demography and clump formation of S. myrtina was strongly linked to associations with V. karroo to initiate bush clump formation. Results suggest that mature V. karroo facilitate the establishment and growth of S. myrtina. These two species were the focus of more detailed investigations to explore the nature and magnitude of their interspecific interactions. I then examined the effects of pairwise tree interactions between V. karroo and S. myrtina on soil and leaf nutrient content. I measureddifferences betweeninter-canopy and sub-canopy soil nutrient content, and the effect of associations on plant leaf nutrients, between pair-size combinations and individual controls. Results confirmed that pair-size tree interactions affected both soil nutrient and leaf nutrient content. All individuals increased soil K, N and organic C in the sub-canopy, while association with V. karrooincreased S. myrtinafoliar N, Pand K. In contrast, association with S. myrtinaloweredV. karroofoliar N, P and K. Small S. myrtina individuals werefound to benefit most from establishing and growing next to a large V. karroo individual, through mechanisms affecting soil and foliar nutrients. Scutia myrtina individuals establishing in association with smaller size classes of V. karroo showed no significant effects. I tested for positive and negative effects of pairwise tree interactions between Vachellia karroo and Scutia myrtina on available soil water and plant water potential (Ψ). This was done by looking at differences betweeninter-canopy and sub-canopy soil moisture and bulk density and associations on plant water stress (pre-dawn and mid-day leaf Ψ), between pair-size combinations and individual controls. I also selectively removed large V. karroo individuals from pairs to confirm the effects of competition andfacilitation. Similar to other studies, results confirmed positive and negative effects of pairwise tree interactions. Small S. myrtina individuals weremost facilitated by establishing and growing up next to a large V. karroo individual, through mechanisms affecting soil water content, bulk density and leaf Ψ. Scutia myrtina establishing in association with other size classes of V. karroo were much less facilitated, showing no significant effects. In contrast, large S. myrtina showed competitive interactions with V. karroo. , Thesis (MSc) -- Faculty of Science, Botany, 2022
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- Date Issued: 2022-10-14
Elele nje usathetha: Ukukhapha as an expression of amaXhosa language world-sense
- Authors: Dana, Zikho
- Date: 2022-10-14
- Subjects: Xhosa language Discourse analysis , Guides (Spiritualism) , Grief Religious aspects , Historical linguistics , Xhosa language Religious aspects , Xhosa (African people) Death , Death Religious aspects
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406309 , vital:70257
- Description: This study examines ukukhapha as an expression of amaXhosa language world-sense. Firstly, it examines how ukukhapha as a rite of passage to accompany the spirit of the deceased from the physical realm into the spiritual realm maintains the nexus between the living and the dead. Secondly, it explores ukukhapha as a ritual of collective mourning. Both dimensions of the study are pursued using language as a point of departure. This study draws on four key texts written across different times in history, namely: Intlalo kaXhosa (The Social Life of amaXhosa) by Tiyo Burnside (TB) Soga (1974); the three volume Greater Dictionary of isiXhosa (1989, 2003 and 2006); Nokuzola Mndende’s (2002) PhD thesis entitled: Signifying practices: AmaXhosa ritual speech; and Khaya Dlanga’s (2015) memoire: To Quote Myself. This thesis examines ukukhapha in the context of death to establish how amaXhosa speak about death and how this shapes their understanding and its practice. Discourse analysis is employed to clarify some practices and examples of ukukhapha. It’s also used to trace the evolution of ukukhapha over time in isiXhosa. It is utilized as a reservoir of knowledge epitomizing the world-sense of amaXhosa rather than solely as a means of communication. This study reveals that while ukukhapha as a ritual slaughtering of an ox to accompany the deceased is found in literature, its examination as a practice of communal and collective grief is scanty. The four key texts studied in this thesis reveal that ukukhapha goes beyond a mere ritual slaughtering of a sacrificial beast to accompany the spirit of the deceased to the ancestral realm. It is a practice that has allowed amaXhosa to collectively grief. Furthermore, it has provided the bereaved various forms of support which are pivotal in maintaining and strengthening kinship and communal ties among the living. This study further reveals that for the Africans in general, and for amaXhosa in particular, death is not the end of life. It is a continuation of life where the deceased morphs and graduates to an ancestor who joins a larger community of ancestors who act as intermediaries between the living and uMdali, the Creator. The findings demonstrate that through ukukhapha, there is no bifurcation between gender and age, rather they complement each other as the successful execution of the mourning period and farewell of a loved one is dependent on the roles played by both women and men respectively. , Olu phando luceba ukuphonononga ukukhapha njengendlela yokuphila equlathwe kulwimi lwamaXhosa. Okokuqala, luzakuphanda indlela ukukhapha njengesiko lokukhapha umphefumlo womfi ukusukela kwelenyama ukuya kwelemimoya kugcina ngayo ubudlelwane phakathi kwabaphilayo nabaleli ukuthula. Okwesibini, luzakuphanda ukukhapha njengesiko lokuzila ndawoni nye. Zombini ezi nkalo zizakuvelelwa ngokugxila kulwimi. Olu phando lucaphula kwimibhalo emine engundoqo kumaxesha ohlukileyo kwimbali, iquka: Intlalo kaXhosa owabhalwa nguTiyo Burnside Soga (ngowe1974); isichazi-magama esinemiqulu emithathu iThe Greater Dictionary of isiXhosa (ngowama-1989, owama-2003 nowama-2006); ithisisi yePhD kaNokuzola Mndende (ngowama-2002) ebizwa Signifying practices: amaXhosa ritual speech; nencwadi engunomalisa wobom, ebhalwe nguKhaya Dlanga (ngowama-2015) ebizwa To Quote Myself. Le thisisi isebenzisa ukukhapha kwilixa lokufa ukuphanda indlela amaXhosa athetha ngkufa, nokuba le ndlela yokuthetha iyichaphazela njani indlela abakuqonda ngayo ukufa nendlela abakhaphana ngayo. IDiscourse Analysis isetyenziswa njengesixhobo sokucacisa ukukhapha. Iphinde isetyenziswe ukunika imizekelo yeli siko nendlela yokuphila kwakunye nendlela ukukhapha kutshintshe ngayo ekuhambeni kwexesha kulwimi lwesiXhosa njengokuba sizakusetyenziswa njengovimba wolwazi, endaweni yokusetyenziswa njengesixhobo sonxibelelwano kuphela. Olu phando lubonisa ukuba njengokuba ukukhapha njengesiko lokuphalaza igazi lenkomo ukukhapha umfi kubhaliwe ngako kuncwadi, indlela abaphilayo enyameni abakhaphana ngayo iyasilela kuncwadi. Le mibhalo mine echongiweyo nephononongiweyo kolu phando ivelisa ukuba ukukhapha akuphelelanga ekuphalazeni igazi lenkomo kuphela njengesiko lokukhapha umfi ukuze awelele kweleminyanya, yindlela eyavumela amaXhosa ukuba azile ngemanyano apho uluntu luxhasa abafelweyo ngeendlela ezahlukeneyo ezithi zomeleze imanyano phakathi kwabazalanayo noluntu lwabaphilayo. Olu phando lutyhila into yokuba kumaAfrika jikelele, ingakumbi amaXhosa, ukufa ayikuko ukuphela kobom, nto nje luhambo olugqithisa umfi kubom obulandelayo apho ongeza kwinani kwelezinyanya apho izinyanya zilikhonco phakathi koMdali nabaphilayo. Iziphumo ngokukhapha zibonisa ukuba akukho ukuchasana phakathi kwesini neminyaka, nto nje, le miba mibini iyathungelana ekuncediseni nasekuqinisekiseni ukuba abafazi namadoda benza iindima zabo ngokufanelekileyo ekuqinisekiseni ukuba ixesha lezila nokubeka umfi kwikhaya lakhe lokugqibela ziyimpumelelo. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
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- Date Issued: 2022-10-14
In vitro pharmacological screening of thiazolidinedione-derivatives on diabetes and Alzheimer’s potential therapeutic targets
- Authors: Arineitwe, Charles
- Date: 2022-10-14
- Subjects: Diabetes Treatment , Alzheimer's disease Treatment , Antioxidants Therapeutic use , Rosiglitazone , Hypoglycemic agents , In vitro screening , Thiazolidinedione Derivatives
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/232171 , vital:49968
- Description: There is an increased prevalence of diabetes and other non-communicable diseases in Sub-Saharan Africa and globally. In South Africa, the prevalence of type 2 Diabetes mellitus is currently estimated at 9.0% in people aged 30 and older and is expected to increase. Diabetes-related complications result in acute alterations in the mental state due to poor metabolic control as well as greater rates of decline in cognitive functioning with age, higher prevalence of depression and increased risk of Alzheimer’s disease. Alzheimer’s disease is the most common form of dementia in older adults and possibly contributes to 60 - 70% of cases. Alzheimer’s disease remains incurable, its progression inevitable with the currently available symptomatic therapies being palliative while the treatment of diabetes relies on insulin preparations and other glucose-lowering agents. Current treatment options have numerous side effects such as hypoglycaemia, diarrhoea, weight gain and abnormal liver function. This has geared the investigation of new generations of small molecules which exhibit improved efficacy and safety profiles. On this basis, several studies have shown that thiazolidinediones and their corresponding derivatives exhibit a broad spectrum of biological activities including anti-inflammatory, and antioxidant activities. Furthermore, recent evidence from experimental, epidemiological, and clinical studies highlight the utility of antioxidants for treating diabetes and its complications. Interestingly, there is increasing evidence that links diabetes and Alzheimer’s disease due to their pathophysiology and suppressing glycaemia has been shown to be beneficial in Alzheimer’s disease treatment. Accordingly, the aim of this study, was to evaluate the anti-diabetic and anti-Alzheimer’s properties of four novel synthesized thiazolidinedione-derivatives owing to their antioxidant properties. Methods The aim of this study was achieved through performing ferric reducing antioxidant power activity, 2,2’-Diphenyl-1-Picry Hydrazyl radical scavenging activity, α-amylase inhibition, α-glucosidase inhibition, aldose reductase inhibition, protein tyrosine phosphatase-1B inhibition, dipeptidyl peptidase-4 inhibition, acetylcholinesterase inhibition, matrix metalloproteinase-1 inhibition, and β-amyloid aggregation inhibition assays. In addition, peroxisome proliferator-activated receptor-γ activation was performed through docking studies. To establish physicochemical properties of TZD derivatives investigated, further in-silico studies were done using SwissADME tools. Results To this end, in-vitro and in-silico studies were successfully performed. In-silico ADME profiling predicted these derivatives to be drug-like with moderate to good solubility in the GI and not blood-brain barrier permeable. Furthermore, docking of these molecules against PPARγ predicted a similar mode of action to that of thiazolidinediones using Rosiglitazone as the standard drug with TZDD2 and TZDD4 forming equivalent conformations to that of Rosiglitazone in the same binding site and TZDD3 having an equivalent LBE to that of Rosiglitazone (-8.84 and -8.63kcal/mol respectively). In-vitro evaluation predicted a moderate antioxidant activity with TZDD2 and 3 exhibiting the highest FRAP activity and DPPH radical scavenging activity. Furthermore, enzymatic inhibition assays showed a relative inhibition activity with TZDD3 exhibited > 100% inhibition in concentrations ≥ 30 μg/mL and TZDD1, 2 and 4 exhibited ≥ 50% inhibition activity in all the concentrations (10, 20, 30, 40 and 50 μg/mL) in the α-amylase inhibition assay. Similarly, in the α-glucosidase inhibition assay, all the four derivatives exhibited a concentration dependent activity with TZDD3 showing the most activity. All the four derivatives exhibited ≥ 30% inhibition in the aldose reductase inhibition assay except TZDD1 at 10 μg/mL. TZDD4 exhibited a concentration dependent inhibition activity in the protein tyrosine phosphatase-1B inhibition assay. Interestingly, TZDD3 showed a decreasing inhibition activity as its concentration increased from 10 μg/mL through to 50 μg/mL. In the dipeptidyl peptidase–4 inhibition assay, TZDD2 and TZDD4 exhibited ≥ 20% inhibition activity across all the concentrations and in the acetylcholinesterase assay, TZDD1, 3 and 4 exhibited ≥ 25% across all the concentrations. Interestingly, in the matrix metalloproteinase-1 inhibition assay, some of these derivatives exhibited partial activation activity and partial inhibition with TZDD1 showing activation in concentrations 10 and 20 μg/mL and inhibition in concentrations 30, 40 and 50 μg/mL. TZDD4 showed activation in all the concentrations. In the β-amyloid aggregation assay, all the four derivatives showed inhibition activity ≥ 10% except TZDD1 at 50 μg/mL. Conclusions Diabetes mellitus and Alzheimer’s disease are a type of pathology of global concern, and several researchers worldwide have strived to search for novel therapeutic treatments and prevention for diabetes as well as Alzheimer’s disease. Recent studies provide a direct link v between diabetes mellitus and Alzheimer’s disease, and the need to find novel drugs that can mitigate these two is of increasing interest. In our search for antidiabetic and anti-Alzheimer’s activity, TZD derivatives (TZDD1, TZDD2, TZDD3 and TZDD4) exhibited good antioxidant activity, anti-hyperglycaemic activity and a relatively promising anti-Alzheimer’s activity. This was observed from the in vitro evaluation performed which included α – amylase, α – glucosidase, aldose reductase, PTP1B, DPP4, amyloid β aggregation, and AChE inhibition assays. Furthermore, docking of the derivatives against PPARγ predicted a similar molecular interaction to that of thiazolidinediones using Rosiglitazone as the standard drug. Furthermore, in silico ADME profiling predicted the derivatives to have moderate to good solubility in the GI (good GI bioavailability), and also exhibited excellent drug likeness. However, they are predicted not permeate the BBB. Further in silico studies and in vivo should be conducted to establish toxicities, as well as drug delivery to the brain for effective therapeutic effect against Alzheimer’s disease. , Thesis (MSc) -- Faculty of Pharmacy, Pharmacology, 2022
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- Date Issued: 2022-10-14
Mentoring as social learning value creation in two South African environmental organisations: a social realist analysis
- Authors: Hiestermann, Michelle
- Date: 2022-10-14
- Subjects: Social realism , Social learning , Mentoring , Environmental education South Africa
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/366248 , vital:65846 , https://doi.org/10.21504/10962/366248
- Description: South Africa is facing overwhelming crises of educational quality, record rates of unemployment (especially amongst youth) and environmental issues and risks, further exacerbated by the Covid-19 pandemic. Environmental education research that addresses these challenges is critical to ensuring that future generations thrive in a warming climate. South Africa needs environmental leaders; we therefore need to understand and explore the possibilities of mentoring young professionals in environmental organisations in South Africa. Several initiatives have been developed to contribute to the mentoring of young professionals in South African environmental organisations. This study drew on a critical realist ontology, social realist meta-theory and domain specific theory on mentoring and evaluation to explore mentoring as a value creating proposition in two environmental organisations in South Africa that were part of the national Groen Sebenza youth employment creation programme which had a strong focus on mentoring. To strengthen conceptual analytical tools on mentoring, I undertook an immanent critique of domain specific mentoring theory to develop a more appropriate foundation for mentoring theory in the environmental sector that was not subject to the historical influence of human capital theory only (which has tended to dominate the field’s literature). I then developed in-depth understanding of mentoring in two case study contexts, namely a non-profit environmental organisation and an environmental consulting company, using qualitative research approaches that included contextual profiling, case study research and mirror data workshops. Analytically, I considered the case data drawing on the value creation evaluation framework of Wenger-Trayner and Wenger-Trayner (2014) which itself was developing as an analytical framework as the study developed. I strengthened the analytical framework with social realist interpretations drawing on Archer (1995). This offered me a way of developing an in-depth understanding of the factors which constrain or enable the value creation possibilities of mentoring, with a view to inform human capacity development initiatives that support mentoring in the environment sector. It was possible to explain the value creation possibilities of mentoring within two case study environmental organisations through considering mentoring as a social learning process of value creation and this overcame some of the shortfalls identified in other early learning theories as well as theories of mentoring. The research revealed how mentoring can provide a value creation social learning trajectory for unemployed youth. A social realist perspective explained how young professionals expanded their primary agency, through full participation in workplace communities of practice, to find their identity as corporate agents in the workplace with their mentors. In this research, Social Realist ontology, theory and methodology was able to achieve what Human Capital Theory could not and provided an account of the interplay of structure, culture and agency over time, through emergent properties and the separation of structure and agency. Thus, it was possible to avoid conflation and the limitation of theory of the present tense, with a deeper, ontologically robust explanation of mentoring as social learning and social change and a social realist orientation to human capacity development. South Africa has a history of oppression, inequality and injustice and requires social processes that are reflexive, critical, emancipatory and transformative. Therefore, this research required theory and approaches that could explain mentoring of unemployed youth, as a common good initiative for a more just and sustainable society. As shown in this study, a Social Realist approach can uncover the underlying generative mechanisms and make the implicit more explicit in research, policy and strategy, offering a robust alternative to the tenets of Human Capital Theory that have driven much mentoring research in South Africa and elsewhere to date. , Thesis (PhD) -- Faculty of Education, Education, 2022
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- Date Issued: 2022-10-14
Stock structure of Patagonian toothfish Dissostichus eleginoides (Smitt 1898, family Nototheniidae) in the Southwest Atlantic
- Authors: Lee, Brendon
- Date: 2022-10-14
- Subjects: Otoliths , Patagonian toothfish Geographical distribution , Fish tagging , Biogeography , Microstructure , Microchemistry
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/365599 , vital:65763 , DOI https://doi.org/10.21504/10962/365599
- Description: The identification of discrete self-sustaining productive units in marine populations is essential for achieving sustainable fisheries objectives. Marine fish populations frequently exhibit dynamic characteristics across their life-histories, displaying variability in spatial structure and mixing patterns, both within and among populations. The incoherent application of management boundaries on biological populations can bias stock assessment results and have important implications on sustainable fisheries management. Patagonian toothfish (Dissostichus eleginoides) is a long-lived, slow-growing, late-maturing, deep-sea, benthopelagic species. It forms the basis of important and highly lucrative industrial and artisanal fisheries across its distribution. Patagonian toothfish have complex life-histories characterised by high dispersal potential during the egg and larval phase, a wide depth range because of their ontogenetic migratory behaviour, and large adult size that is capable of undertaking long-distance active movements (>200 km). These characteristics provide opportunities for high levels of connectivity, and as such, the stock structure is not well understood. We applied an integrated, multidisciplinary approach to provide an improved understanding of the complex stock structure dynamics for Patagonian toothfish on the Patagonian Shelf, specifically in relation to the shelf, slope, and deep-sea plains around the Falkland Islands. Research results were focused on aspects pertaining to (1) geographic variation in phenotypic characters (otolith shape); (2) a description of the spatial-temporal distribution patterns; (3) the active movements of deep-sea adults (tag-recapture study); and (4) the identification of early life-history dispersal through otolith microstructure and microchemical chronologies. Results from the study indicate high regional connectivity during the early life-history stages derived from at least two spawning contingents into spatially discrete nursery areas (cohort groups) on the Falklands Shelf. Fish followed distinct ontogenetic pathways into deeper waters adjacent to the areas wherein juvenile settlement into a demersal habitat occurred. There is little to no evidence of mixing among cohort groups during their ontogenetic migration into deep-sea adult habitats, reflecting a mixed population based on oceanographically defined egg and larval dispersal. The majority of the adult component of the population continue to display high site fidelity. However, between 9 and 25% of the population, consisting predominantly of larger reproductively capable adults undertake long-distance dispersal behaviour, identified as home-range relocations from the adult deep-sea habitats towards three of the known southern spawning grounds in the region. Results are suggestive of a requirement for improved collaborative efforts for regionally-based management approaches with careful consideration of local stock contingents. Future monitoring and research priorities should focus on the identification of reproductive potential, dispersal pathways and settlement patterns of stock contingents to inform the dynamics of mixed stock origins across the Patagonian region. While many aspects regarding the stock structure remain unresolved, results derived from the current studies can be used to inform the development of management measures to ensure the continued recovery and sustainable management of Patagonian toothfish within the region. , Thesis (PhD) -- Faculty of Science, Ichthyology and Fisheries Science, 2022
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- Date Issued: 2022-10-14
The role of Facebook in a survivor’s post-assault life: rape on campuses, women activists, and mental health
- Authors: Witi, Sinethemba Juliet
- Date: 2022-10-14
- Subjects: Online social networks , Rape in universities and colleges South Africa Makhanda , Student movements South Africa Makhanda , College students Mental health South Africa Makhanda , Sex crimes South Africa Makhanda , Social media and college students South Africa Makhanda , Intersectionality (Sociology) , Womanism
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405952 , vital:70222
- Description: The rise of Social Networking Sites (SNSs) has raised concerns about the negative impact social media platforms, and in particular Facebook, has on their users. Research has linked the excessive use of Facebook with mental health challenges such as loneliness, depression, and stress. This research examined how Yolanda Dyantyi, a gender rights activist registered as a student from 2015 to 2017 at Rhodes University, used Facebook as an outlet following the #RUreferencelist protests and her subsequent permanent exclusion from the institution for her role in the protests. The study explored Dyanti’s use of Facebook, examining in particular her ongoing activism, her mental health challenges, and her struggles to re-establish herself in a community after the exclusion from Rhodes. The study employed an intersectional feminist theoretical framework and drew on a qualitative content analysis, a semi-structured interview, and the scroll back method to review the Facebook posts she had made. A thematic analysis of the data showed that Dyantyi is a multifaceted, and evolving Facebook user and contrary to existing research her prolific use of Facebook has had positive effects on her mental health and has enabled her to build social capital. The study suggests that activism is an important component to research alongside studies of mental health on such media platforms. , Thesis (MA) -- Faculty of Humanities, School of Journalism and Media Studies, 2022
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- Date Issued: 2022-10-14
Development and optimisation of a qPCR assay for the enumeration of Cryptophlebia leucotreta granulovirus (CrleGV) used for commercial applications
- Authors: Mela, Thuthula
- Date: 2022-10-14
- Subjects: Cryptophlebia leucotreta granulovirus , Cryptophlebia leucotreta , Late expression factor 8 (LEF-8) , Late expression factor 9 , Dark field microscopy , Genomic DNA , Polymerase chain reaction , Plasmids
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362949 , vital:65377
- Description: The citrus industry contributes significantly to the South African agricultural sector. Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is highly important to the South African citrus industry as it is classified as a phytosanitary pest by most international markets. Thaumatotibia leucotreta has caused an estimated annual loss of up to R100 million to the industry. In order to control T. leucotreta in South Africa, an integrated pest management (IPM) programme has been used. One of the components of this programme is Cryptophlebia leucotreta granulovirus (CrleGV), which has been formulated to a registered biopesticide namely Cryptogran and has been successfully applied in the field for over 15 years. To use CrleGV as biopesticides, quantification of the viral particles is required to perform bioassays for field trials and formulation, among other applications. Darkfield microscopy is a traditional method used for the quantification of CrleGV; however, the method is characterised as being subjective, tedious, labour intensive, and time-consuming. This study aims to develop and optimise a qPCR technique to accurately quantify CrleGV-SA OBs using plasmid DNA for downstream applications. Firstly, lef-8, lef-9, and granulin conserved genes from CrleGV-SA and CrleGV-CV3 genome sequences were analysed by performing multiple alignments to evaluate the degree of identity between these genes. This was done to design two sets of oligonucleotides (internal and external) from regions with the highest identity. Subsequently, in silico testing was done to evaluate the designed oligonucleotides to determine whether they specifically bind to the selected target regions. Secondly, three sets of DNA plasmids (pJET1.2-Gran, pJET1.2-lef-9, and pJET1.2-lef-8) were constructed, each containing a target region for either granulin, lef-9, and lef-8 genes for use as standards in a downstream qPCR assay. This was achieved by first extracting gDNA from CrleGV-SA OBs and using the gDNA as a template to PCR amplify the target regions of the selected gene regions with the designed oligonucleotides. Subsequently, the PCR amplified regions were then directly ligated into the pJET1.2/blunt vector, and the plasmids were confirmed by colony PCR, restriction enzyme digestion, and Sanger sequencing. Thirdly, two different methods of CrleGV-SA gDNA extraction were compared to determine which method has the best yields in terms of concentration. The extraction methods compared were the Quick-DNA Miniprep Plus kit according to manufacturer’s instructions (Method 1a), pre-treatment with Na2CO3 prior to using the Quick-DNA Miniprep Plus kit (Method 1b), pre- treatment with Na2CO3, and neutralisation with Tris-HCl prior to gDNA extraction using the Quick-DNA Miniprep Plus kit (Method 1c) and the CTAB method (Method 2). The gDNA concentration and purity for all samples were determined using a Nanodrop spectrophotometer. Method 1c (Na2CO3 and Tris-HCl pre-treated plus Quick-DNA Miniprep Plus kit) was the most efficient at extracting genomic DNA compared with the other methods, resulting in the highest DNA concentration in short processing time. Fourthly, plasmid standards were evaluated for use in the qPCR assay. This was done as it was important to consider the efficacy of the oligonucleotides; including the ability of the oligonucleotides to anneal to the appropriate segment of DNA without extensive formation of oligonucleotides dimers, non-specific annealing, or formation of secondary structure. In addition, it was done to ensure that highly accurate standard curves were generated. The standard curves were to be utilised in the downstream qPCR assay to determine the quantity of test samples by interpolation, reading from the values within the standard curve. Lastly, darkfield microscopy and qPCR methods of enumeration were compared to verify their accuracy and determine the most consistent and comparable method. This was achieved by quantifying the purified, crude-purified, and viral formulated CrleGV-SA suspensions using these methods. Subsequently, a statistical analysis was conducted to compare the results produced by the two enumeration methods. The obtained results showed that the granulin, lef- 8 and lef-9 qPCR values did not significantly differ from the darkfield microscopy results. The findings of this study revealed that the two assays, lef-8 qPCR and lef-9 qPCR, were more robust, sensitive, and efficient for the quantification of CrleGV-SA. Thus, this study has successfully developed a qPCR assay that is comparable with the traditional darkfield microscopy counting technique. This is the first study to use the qPCR technique to enumerate CrleGV-SA using plasmid standards. The developed qPCR assay is reliable, rapid, and cost- effective and has a great potential to be used as an alternative method to darkfield microscopy in the laboratory and commercial settings. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2022
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- Date Issued: 2022-10-14