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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

Mobilising indigenous technologies of making oshikundu and uumboloto to motivate and enable sense making of the topic carbon dioxide by grade 8 rural school learners

  • Authors: Nandjedi, Fredinard Nghinaounditala
  • Date: 2022-10-14
  • Subjects: Science Study and teaching (Secondary) Social aspects Namibia , Culturally relevant pedagogy Namibia , Ethnoscience Namibia , Carbon dioxide
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/405357 , vital:70164
  • Description: Poor performance in Science has been noted in most rural schools and this has become a concern to education planners and implementers. Part of the failure is said to be caused by inadequate school resources, under-preparedness of teachers to teach Science, poor command of the Language of Learning and Teaching, negative attitudes that are accompanied by lack of insights into the value of Science, low self-efficacy, and poor-quality environments for learning Science. In this regard, literature has revealed that many Science teachers in Namibia do not consider learners’ local indigenous knowledge (IK) also known as indigenous technology to mediate learning. Yet, it is a requirement of the Namibian Science curriculum. I assume that this could be due in part to the fact that the Science curriculum is not explicit on how IK should be integrated into Science teaching. It is against this backdrop that this study sought to explore the opportunities IK integration into Science may offer in mediating learning and sense-making on the topic of carbon dioxide (CO2). Learners’ indigenous technological practices of making oshikundu and uumboloto were used as vehicles of learning. This qualitative case study is underpinned by the interpretive and indigenous research paradigms. Within the indigenous research paradigm, I focused on the Ubuntu perspective. This study was conducted at a rural under-resourced school in the Ohangwena region in Namibia. Thirty Grade 8 learners, one science teacher and two expert community members were involved as participants. Data were gathered using focus group interviews (sharing circles), group activities, participatory observations, and journal reflections. Data interpretation and analysis were done using Vygotsky’s sociocultural theory and Ogunniyi’s contiguity argumentative theory. A thematic approach to data analysis was adopted. That is, an inductive approach was employed whereby sub-themes were identified, and thereafter common sub-themes were combined into themes. The findings of this study revealed that the process of making oshikundu and uumboloto can be used to enable learners to make sense of the topic of CO2 and other related concepts. Furthermore, the study revealed that hands-on practical activities done with easily accessible resources which are related to learners’ indigenous technologies help learners learn Science easily. The study thus recommends that educators should use oshikundu and/or uumboloto to mediate learning of topics such as CO2. Science teachers should always try to tap into learners’ socio-cultural backgrounds in their lessons to enhance better understanding of Science concepts. , Thesis (MEd) -- Faculty of Education, Education, 2022
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  • Date Issued: 2022-10-14

Mobilising the indigenous technology of making soap to mediate learning of saponification in organic chemistry

  • Authors: Neporo, Johannes Kanyetu
  • Date: 2022-10-14
  • Subjects: Chemistry Study and teaching (Secondary) Social aspects Namibia , Culturally relevant pedagogy Namibia , Ethnoscience Namibia , Saponification , Ubuntu (Philosophy) , Pedagogical content knowledge
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/405368 , vital:70165
  • Description: Scholars across the world are advocating for culturally responsive pedagogies that allow for the integration of indigenous knowledge (IK) in science teaching. This is in the hope of making science accessibleand relevant to learners from different social, economic and cultural backgrounds. Although the Namibian curriculum welcomes the integration of IK in teaching, it, however, does not stipulate how it should be implemented. It is against this backdrop that this interventionist study aimed to mobilise the indigenous technology of making soap to mediate the learning of saponification in organic chemistry. This study is underpinned by the interpretive and indigenous research paradigms. Within these paradigms, it employed a qualitative case study research design. The study was conducted in Walvis Bay in Namibia with four Grade 11 chemistry teachers, two expert community members and a critical friend who were purposively and conveniently sampled. Data were gathered using semi-structured interviews, semi-structured questionnaires, workshop discussions, participatory observation, stimulated recall interviews and journal reflections. Vygotsky’s Socio-Cultural Theory (SCT) and Shulman’s Pedagogical Content Knowledge (PCK) were used as theoretical frameworks. Within PCK, Mavhunga and Rollnick’s Topic-Specific Pedagogical Content Knowledge (TSPCK) served as an analytical framework. A thematic approach to data analysis was employed. That is, data were analysed inductively to come up with sub-themes. Thereafter, common sub-themes were combined to form themes. The findings of the study revealed that the Grade 11 chemistry teachers demonstrated positive attitudes toward the integration of IK in their teaching. However, they seemed not tohave pedagogical insights on how to do it. Despite this, they learnt, interacted and participated actively during the two expert community members’ presentation workshops on making soap. That subsequently enabled them to co-developan exemplar lesson plan on saponification that integrated IK. This study implies that there is a need for Chemistry teachers to be empowered on how to make science accessible and relevant to learners’ socio-cultural backgrounds. The study thus recommends that higher education institutions and educational authorities reform and amend the curriculum to cater for the integration of IK. The study further recommends that Chemistry teachers should tap into the cultural heritage of expert community members in mediating the learning of science concepts. Lastly, Chemistry teachers are encouraged to form professional learning communities to develop themselves professionally. , Thesis (MEd) -- Faculty of Education, Education, 2022
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  • Date Issued: 2022-10-14

Molecular identification of potential ciprofloxacin degrading bacteria and determination of its possible breakdown intermediates in rivers, Eastern Cape

  • Authors: Ncgauzele, Zenande Rose
  • Date: 2022-10-14
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/403003 , vital:69913
  • Description: Thesis embargoed. To be released early 2026. , Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2023
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  • Date Issued: 2022-10-14

Movement patterns of the iconic giant kingfish Caranx ignobilis from Southern Africa

  • Authors: Dixon, Russell Bruce
  • Date: 2022-10-14
  • Subjects: Caranx Africa, Southern , Caranx Migration , Underwater acoustic telemetry , Carangidae Africa, Southern , Fish tagging
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/362797 , vital:65363
  • Description: Giant kingfish Caranx ignobilis, the largest species in the family Carangidae, are global icons as apex marine predators. They are widespread in tropical to subtropical regions globally, where they are of high importance to ecosystems and fisheries. During summer, adults aggregate for spawning, making them vulnerable to overfishing. The world’s largest recorded C. ignobilis aggregation is in southern Mozambique. Some of these aggregating individuals (an unknown proportion) have been recorded passing into South African waters. Furthermore, a unique aggregation of adult C. ignobilis in South Africa’s Mtentu Estuary has attracted global attention but remains unexplained, hence warranting investigation. Research on C. ignobilis globally has shown relatively small home ranges. Research in southern Africa has been limited and inconclusive. Thus, the broad aim of this study is to describe the movement patterns of C. ignobilis from southern Africa. Long-term (36 years) mark-recapture data from the Oceanographic Research Institute’s Co-operative Fish Tagging Project, comprising 3 729 tagged C. ignobilis and 144 recaptures, were analysed. While 74% of recaptures were recorded < 1 km from the tagging location, long-distance movements of up to 419 km were also recorded (mean = 15 km). Although adults moved significantly (p < 0.01) greater distances than juveniles, they also displayed high levels of site fidelity. Seasonal trends included evidence of a summer migration; however, there was still considerable uncertainty regarding exact movements. Therefore, 43 C. ignobilis were acoustically tagged and subsequently monitored along the east coast for over five years with the Acoustic Tracking Array Platform’s passive receiver array. All acoustically tagged adult C. ignobilis migrated to southern Mozambique each year (with minor exceptions), from distances of up to 632 km. When not migrating, South African-based fish showed consistent inter-annual fidelity to individual home ranges. Although coastal home range length (excluding migrations) varied considerably between individuals, even the mean length (92 km) was greater than any previously recorded C. ignobilis home range, globally. In contrast to the southern Mozambique aggregation, the Mtentu Estuary aggregation seems to comprise of individuals showing fidelity to that region. The passive tracking of eight acoustically tagged individuals in the Mtentu Estuary revealed clear trends. Statistical modelling showed that estuarine presence was strongly associated with periods of cold coastal upwelling. Diel movement patterns showed that the utilisation of warm surface waters ~ 4 km upstream during the day was followed by nightly departures to the mouth or sea. Thus, it is likely that this majestic aggregation is for thermal refuge; specifically, for daily re-warming after feeding in cold waters at night. Findings from this study are of global ecological interest and have direct applications for local fisheries management and the development of sustainable eco-tourism. Protecting these vulnerable aggregations is of the utmost importance for the future of this species in southern Africa. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2022
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  • Date Issued: 2022-10-14

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

On legal expressivism, incorporeal injuries and the equal protection clause: an analysis through the lens of the Civil Union Act

  • Authors: Tsele, Michael Vuyo
  • Date: 2022-10-14
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/405434 , vital:70171
  • Description: Thesis embargoed. To be released in 2024. , Thesis (LLM) -- Faculty of Law, Law, 2022
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  • Date Issued: 2022-10-14

Orthographic knowledge in isiXhosa and its relation to phonological processing, letter-sound knowledge, reading and spelling

  • Authors: Daries, Mikaela Ann
  • Date: 2022-10-14
  • Subjects: Xhosa language Orthography and spelling , Phonological awareness , Psycholinguistics , Oral reading Usage , Literacy South Africa , Reading Phonetic method
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/406703 , vital:70300
  • Description: Despite international research confirming its importance, writing and related metalinguistic skills have often been neglected in comparison to reading in literacy research (Cunningham et al., 2001; Castles & Coltheart, 2004; Nag, 2007; Roman et al., 2009; Zhao et al., 2017). On a national level there are very few studies that have explored the writing aspect of literacy in South Africa, and none that has investigated orthographic knowledge in a Southern Bantu language, such as isiXhosa. In an attempt to address this gap, this thesis explores orthographic knowledge and its components in isiXhosa. In particular, it seeks to investigate the unique predictors of word specific and general orthographic knowledge as well as their role for reading and spelling in isiXhosa while controlling for phonological awareness (PA), rapid automatized naming (RAN), and letter-sound knowledge. Furthermore, the thesis attempts to situate its findings within the main premises of the self-teaching hypothesis and dual route approach to orthographic processing in order to contribute to linguistic theories of reading with cross-linguistic evidence (Jorm & Share, 1983; Share & Jorm, 1987; Share, 1995; Grainger & Ziegler, 2011). A quantitative cross-sectional study was conducted with 140 isiXhosa home language third grade learners in which word specific and general orthographic knowledge tasks were specifically designed. These tasks were administered along with oral reading fluency (ORF), spelling, PA, RAN, and letter-sound knowledge. The findings revealed that letter-sound knowledge and PA contributed the largest variance towards both word specific and general orthographic knowledge. Further, word specific orthographic knowledge and letter-sound knowledge were the only significant predictors of spelling. Similarly, both word specific and letter-sound knowledge were significant predictors of reading, along with RAN and general orthographic knowledge. Quantile linear regression analyses revealed that word specific orthographic knowledge was a robust predictor of spelling and letter-sound knowledge was a robust predictor of reading across ability levels confirming the importance for word specific orthographic knowledge for spelling and letter-sound knowledge for reading in isiXhosa. In relation to the two reading theories considered in this thesis, the findings reflect similarities between the assertions of the self-teaching hypothesis and current thesis with suggestions made for further inquiry. The dual route approach to orthographic processing provides insights into the potential processing of orthographic information while reading in isiXhosa. The findings of this study confirm the importance of orthographic knowledge for reading and spelling for languages with transparent orthographies such as isiXhosa. , Thesis (MA) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2022
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  • Date Issued: 2022-10-14

Oversight mechanisms and service delivery: a case study of municipal public accounts committee oversight of electricity services in Raymond Mhlaba Local Municipality

  • Authors: Mpofu, Sibabalwe
  • Date: 2022-10-14
  • Subjects: Municipal services South Africa , Local government South Africa , Local service delivery , Public sector , Oversight , Economics Sociological aspects , Government accountability South Africa
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/408671 , vital:70515
  • Description: South Africa, as a post-apartheid state is still grappling with socio-economic inequalities such as poverty, unemployment, and inequality. Local government is mandated to play a developmental role and has a responsibility to redress these socio-economic inequalities at grassroots level. According to the Constitution of South Africa, the local government sphere is obligated to adopt and practice good governance. Whilst good governance means different things to different people, this study argues that good governance is characterised by transparency and accountability, and the use of public resources in an accountable and sustainable manner in order to ensure the progressive realisation of the needs of the municipal residents. This study explores the relationship between oversight and service delivery by examining the Municipal Public Accounts Committee’s oversight of electricity services in Raymond Mhlaba Municipality (herein referred to as RMM) in South Africa’s Eastern Cape Province. It makes use of a case-study research design to inform its data collection and analysis. Officials responsible for electricity service provision and councillors responsible for overseeing the performance of electricity services in RMM were interviewed. These interviews were analysed together with a document analysis of RMM, and a review of relevant local government legislation. The research findings indicate that the Municipal Public Accounts Committee (herein referred to as the MPAC) in RMM failed to engage in effective oversight due to (1) a lack of familiarity with the municipality’s plans for electricity services, (2) a lack of familiarity with the targets for revenue collection and expenditure management for electricity services, and (3) a lack of rigorous oversight and monitoring of the municipality’s spending and implementation of targets set out in its electricity plans. This study, therefore, reflects the realities of non-effective oversight in municipalities in the Eastern Cape and proposes a model which can improve some of the dire oversight practices which are prevalent in rural municipalities such as RMM. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2022
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  • Date Issued: 2022-10-14

Photodynamic anticancer and antimicrobial activities of π-extended BODIPY dyes and cationic mitochondria-targeted porphyrins

  • Authors: Chiyumba, Choonzo Nachoobe
  • Date: 2022-10-14
  • Subjects: Dyes and dyeing Chemistry , Mitochondria , Cancer Chemotherapy , Porphyrins , Molecules Models , Photochemotherapy
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/362785 , vital:65362
  • Description: Cancer is among the most devastating diseases and is mainly caused by gene mutation. This could be hereditary, or the mutation could be stimulated due to a lifestyle one lives, such as smoking, which induces lung cancer. The high morbidity rates of cancer are attributed to it being metastatic. The relatively poor physicochemical properties of existing drugs have caused treatment to be ineffective. Photofrin®, Foscan®, and Photogem® are some of the porphyrin-based derivatives approved by the Food and Drug Administration (FDA) for use in photodynamic therapy (PDT). Despite having such drugs, the quest to find better cancer drugs is still ongoing and 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) dyes are among the molecules that are being studied as potential photosensitisers (PS) in PDT. However, these molecules suffer from poor solubility and ineffective generation of singlet oxygen, the main ingredient in PDT treatment. Furthermore, photosensitisers used in PDT face a problem with hypoxic conditions associated with cancer cells, which causes the generation of singlet oxygen to be relatively low. The PS also suffer from the untargeted treatment, increasing their toxicity. Therefore, the main aim of this study was to improve the bioavailability of BODIPY dyes. Thus, a series of BODPIY dyes were synthesised with hydrogen bond accepting atoms and heavy atoms that enhance singlet oxygen generation. Additionally, to override hypoxia conditions, porphyrins with mitochondria targeting properties were synthesised since it has been well established that the mitochondria will always have a decent amount of oxygen in cancerous cells. When employed as PS in PDT studies, these molecules have better cytotoxic abilities than BODIPY dyes, and this potency was credited to their mitochondria targeting ability and efficient singlet oxygen generation. Finally, this study reports the synthesis of di- and mono-substituted BODIPY dyes with improved solubility and porphyrins substituted with triphenyl phosphine, a mitochondria targeting moiety. On the other hand, the work further illustrates the synthesis of β-substituted cationic porphyrin with mitochondria targeting properties. , Thesis (MSc) -- Faculty of Science, Chemistry, 2022
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  • Date Issued: 2022-10-14

Poems caught in dreams

  • Authors: Jafta, Nthabiseng Rose JahRose
  • Date: 2022-10-14
  • Subjects: Creative writing (Higher education) South Africa , South African poetry (English) 21st century
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/406249 , vital:70252
  • Description: My thesis is a collection of Lyrical and Prose Poetry. I am strongly influenced by Marina Tsvetaeva’s observation that “The condition of creation is a condition of dreaming.” As a writer I want to contribute to human knowledge by drawing from a wide literary ancestry, participating in a community of distinct voices and styles to capture and preserve the language of dreams. I fuse inherited knowledge, visions, dreams, my own experiences and what I have discovered through listening to music, reading and my own experiments in exploring poetry in dreams, thoughts and lived experiences. I am inspired by Sindiwe Magona, how she chose to express her spirituality and personal narratives into her work, and Aimé Césaire’s vision “The ground of poetic knowledge, [is] an astonishing mobilization of all human and cosmic forces.” I particularly enjoy intense forms of expression that hold substance and provoke one to elevate in knowledge and in writing. Exploring these combination of forces from these writers affords me an opportunity to write my dreams as reality. Exploring the characters, the different scenes, symbols and colours as poems flashing super/naturally yet leave one with fathomable felt, though sometimes hazy interpretations. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
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  • Date Issued: 2022-10-14

Population dynamics, fire, and reproductive ecology of Oldenburgia grandis (Asteraceae), an unusual fynbos tree endemic to the Eastern Cape

  • Authors: Mostert, Emma Charlotte
  • Date: 2022-10-14
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/365268 , vital:65722
  • Description: Thesis embargoed. Possible release date set for early 2024. , Thesis (MSc) -- Faculty of Science, Botany, 2022
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  • Date Issued: 2022-10-14

Portraits

Production of mannooligosaccharides from pineapple pulp and pine sawdust using Aspergillus niger derived Man26A and determination of their prebiotic effect

  • Authors: Hlalukana, Nosipho Pretty
  • Date: 2022-10-14
  • Subjects: Oligosaccharides , Prebiotics , Lignocellulose , Mannans
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/362853 , vital:65368
  • Description: Lignocellulosic biomass is the most abundant source of renewable biomass on earth. Lignocellulosic biomass consists of cellulose, hemicelluloses and lignin. These can be used as a source of renewable fuel as well as other value-added products . Mannans are part of the hemicellulose fraction of lignocellulosic biomass and are the major hemicellulosic polysaccharide fraction in softwoods, where they are found as galactoglucomannans and as glucomannans. Mannans are also found in hardwoods in the form of glucomannans. Mannans can be enzymatically hydrolysed using endo-mannanases to produce of short chain mannooligosaccharides (MOS). MOS have received significant attention for their prebiotic properties, as they promote the growth of probiotic bacteria, which have positively affects on gut health. This study focused on the production of prebiotic MOS from lignocellulosic biomass waste (LBW) and an evaluation of the prebiotic potential of the produced MOS. An Aspergillus niger derived endo-mannanase, Man26A, was fractionated and biochemically analysed. Purified Man26A had a fold purification of 1.25 and a yield of 41.1%. SDS-PAGE analysis of the enzyme revealed that it had a molecular weight of 46 kDa. The pH and temperature optima of Man26A were determined and the pH optimum was found to be pH 4.0 (but the enzyme displayed high activity over a broad acidic pH range, with up to 90% of the activity retained between pH 3.0 and 7.0). The temperature optimum was 50℃. The enzyme was shown to have the highest specific activity on locust bean gum (52.27 U/mg) and ivory nut mannan (57.25 U/mg), compared to guar gum (29.07 U/mg), which indicated that it was affected by the substitution pattern of the mannans. Man26A produced MOS of different diversity on model mannan substrates, where the MOS produced were mannobiose, mannotriose, and mannotetraose for ivory nut mannan, mannobiose, mannotriose, mannotetraose, and mannopentaose and MOS with a higher degree of polymerisation for locust bean gum, and mannobiose, mannotriose, mannotetraose, mannopentaose, and mannohexose and MOS with a higher degree of polymerisation for guar gum, as determined by thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Pretreatment and characterisation of pineapple pulp (PP) and pine sawdust (PSD) was conducted, and the impact of the pretreatment procedures was analysed using Megazyme sugar kits, thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and microscopic analysis using scanning electron microscopy (SEM) and light microscopy. Compositional analysis of the carbohydrates present in both substrates revealed that they had a glucan content of 36.41 and 50.47% for untreated PP and PSD, respectively. Their respective mannan content was 6.74 and 11.59% and was deemed sufficient for the production of MOS via enzymatic hydrolysis. TGA analysis revealed that untreated and sodium chlorite-acetic acid delignified samples decomposed at approximately the same time, and had a negligible ash content at 600℃, while delignified plus phosphoric acid swollen substrates decomposed at a faster rate, but had a residual ash content at 600℃. FTIR analysis of the substrates revealed slight changes in the structures of untreated and pretreated samples. SEM analysis of PP and PSD showed a change in the morphology of the substrates with subsequent pretreatment steps. Histochemical analysis for lignin for PP and PSD showed successful delignification upon pretreatment. Untreated and sodium chlorite delignified PP and PSD released low amounts of reducing sugars compared to delignified + phosphoric acid swollen substrates. The delignified + phosphoric acid swollen substrates were used for further experiments. MOS produced from delignified and phosphoric acid swollen (Del + PAS) PP and PSD at 0.1 mg/ml enzyme loading and 80 mg/ml (8% (w/v)) substrate concentration, ran between mannose and mannobiose and between mannobiose and manotriose on TLC, with low concentrations of MOS running between mannotetraose and mannopentaose. HPLC analysis of the MOS revealed that Del + PAS PP produced mannose to mannohexose, while Del + PAS PSD produced mannose, mannobiose, and mannotetraose. The MOS were analysed using FTIR, to determine whether the MOS produced contained any acetyl groups, which were present for Del + PAS PSD at 1706 cm-1. The MOS were stable at different pHs, and at temperatures below 200℃. The MOS were also found to be stable in a simulated gastrointestinal environment, in the presence of bile salts and digestive enzymes. The prebiotic effect of the MOS derived from Del + PAS PP and PSD was evaluated. MOS had a proliferative effect on probiotic bacteria (Lactobacillus bulgaricus, Bacillus subtilis and Streptococcus thermophilus). The production of short chain fatty acids (SCFAs) was evaluated on TLC, where no SCFAs were observed on the plate. The effect of MOS on the adhesion ability of bacteria revealed that they do not positively influence the adhesion of probiotic bacteria. The antioxidant activities of 1 mg/ml MOS produced from both substrates were determined to be approximately 15% using the ABTS radical scavenging assay, compared to a radical scavenging activity of 45% for the 0.02 mg/ml gallic acid standard. This study demonstrated that biomass waste could be used to produce prebiotic MOS, which play a positive role in gut ecology and provide health benefits. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2022
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  • Date Issued: 2022-10-14

Profiling Rhodes University students’ substance use during the Covid-19 pandemic lockdown: comparing the AUDIT and CCAPS-62 substance abuse sub-scale

  • Authors: Goosen, Jeslyn Chrismaré
  • Date: 2022-10-14
  • Subjects: College students Substance use South Africa Makhanda , College students Alcohol use South Africa Makhanda , College students Mental health South Africa Makhanda , College students Attitudes , College students Economic conditions , COVID-19 (Disease) , Rhodes University
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/405974 , vital:70224
  • Description: Students are vulnerable to academic distress and mental health concerns. Many struggle to effectively cope with the many demands placed on them from various factions; included but not limited to institutional demands, financial concerns, and parental expectations. With the most recent outbreak of the SARS-Co V-2 (better known as the COVID-19 pandemic) many students have struggled to effectively cope with the changes relating to the nationwide lockdown. Universities had to change the way in which they provide students with the necessary academic material, and many had to return to their familial homes. This had a deleterious effect on the way students performed their daily activities and coping. A rise in impaired mental health was noted. Many students used alcohol as a means of coping during this tumultuous and unprecedented time. Undergraduate students at Rhodes University were asked to complete a survey questionnaire via SurveyMonkey, an online survey service. Data was collected over a ten-day period during July 2020. The AUDIT and the CCAPS-62 Substance Use subscale were used to measure their alcohol intake during lockdown and results was compared. Results indicated a significant positive correlation between the CCAPS-62 substance use subscale and the AUDIT (r = 0.80, n = 930, p < 0.01). Outcomes identified that men tend to drink more than females, and white students tend to drink more than black students. Findings suggests that the CCAPS-62 a multidimensional instrument measuring general distress among students could positively contribute to the reliability and validity of the measure used in a multicultural and multilingual society such as South Africa. , Thesis (MA) -- Faculty of Humanities, Psychology, 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

Reforging Ockham’s Razor: an enquiry into the ontology of parsimony arguments

  • Authors: Dichmont, Thomas
  • Date: 2022-10-14
  • Subjects: Logic , Metaphysics , Ontology , Knowledge, Theory of , Epistemology , Philosophy and science , Occam's razor
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/406736 , vital:70303
  • Description: Nearly every philosopher in English-speaking world has heard of Ockham’s Razor, which is given in one of two ways, don’t multiply entities beyond necessity and all things being equal choose the simpler explanation. Yet it is unclear from the scholarship whether the use of Ockham’s Razor is justified in science and philosophy. However, if it can be shown to ‘get’ us truth, it would gain an unequivocal justification, as disputes that are continued after the parties to the substantive truth of one or the other are defined as frivolous. Alternative, one may contend that explanation could have other criteria of success. The implication of a direct connection between the razor and truth comes with ontological commitments, namely a commitment to realism (about universals) and philosophical theism. This is contrary to the razor’s use as a tool of nominalism and naturalism. I argue in this thesis there that the only possible non-circular justification for Ockham’s Razor is truth and that therefore certain philosophical positions are excluded from using the razor to animate their positions. There is an additional, second criteria for the success of our inquiry, namely the justification must in some way be consistent with the razor, which means the chosen explanation for the razor, must be simpler than any of its rivals and not have superfluous entities, otherwise our justification would be contrary to the advice of the razor. We are presented with a Scylla and Charybdis type problem, we avoid a circularity on the one hand and on the other we must not contradict the razor itself, these are contrary intellectual impulses. So firstly I will look at disciplines outside philosophy for some initial inspiration. If we could answer this question in a ‘non’ philosophical way, the problem would have solved itself in a way that require little change of practice. If lawyers or scientist can account for the razor properly, there is not really a problem of justification, at least not a philosophical one. Second, I consider the realist and theist positions, namely an argument of Aristotle’s in the Posterior Analytics and part of Aquinas’ On the Divine Simplicity. Further, I consider the work of Ockham as a nominalist. Lastly, I consider modern and contemporary philosophy, in the form of Hume, Quine and Sober (a modern writer on the razor). The aim here is to ‘stress test’ the philosophical resources of the various systems and analyse the results to see if they can produce a non-circular result. , Thesis (MA) -- Faculty of Humanities, Philosophy, 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

Revitalisation and indigenisation of the Science curriculum through drum making, drumming, music and dance

  • Authors: Liveve, Angelius Kanyanga
  • Date: 2022-10-14
  • Subjects: Curriculum change Namibia , Science Study and teaching (Secondary) Namibia , Traditional ecological knowledge Namibia , Drum Performance , Drum making , Pedagogical content knowledge , Social learning
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/405482 , vital:70175 , DOI 10.21504/10962/405482
  • Description: The integration of IK is a common phenomenon in many postcolonial states, where it is viewed as a means to redress the injustices of the colonial era. It is believed that the recognition of IK in education represents an acknowledgement of diversity and other ways of knowing. In Namibia, for instance, the National Curriculum for Basic Education encourages the integration of IK in Science teaching. However, this goal is still far from being achieved because the curriculum seems to be silent on how teachers should integrate IK into their teaching. As a result, research shows that many Science teachers in Namibia seem to find it difficult to integrate IK into their science teaching because they were not properly trained to do so during both their pre-service and in-service training. This suggests that there is a dire need to empower science teachers who are implementers of the curriculum on appropriate pedagogical content knowledge on how to integrate IK into their science teaching in particular. It is against this backdrop that this interventionist study sought to explore how to mobilise the indigenous technology of drum making, drumming, music and dance for cultural revitalisation and indigenisation of the science curriculum. The study is underpinned by an interpretivist paradigm and augmented with an indigenous research paradigm. The interpretivist paradigm enabled me to understand the teachers’ perspectives in their contexts. On the other hand, within the indigenous research paradigm, I used the Ubuntu perspective which afforded each of us an opportunity to understand each other’s ways of knowing, doing and being. Within these two complementary paradigms, a qualitative case study approach was employed. The case study was in the form of intervention with six Grade 10 Physics teachers from three senior secondary schools in the Kavango West Region in Namibia. Moreover, a critical friend who was a lecturer at the university and expert community members of the Unongo Cultural Youth Group who are the custodians of the cultural heritage. Data were generated using semi-structured interviews, workshop discussions (audio-recorded), observations (participatory and lesson observations), stimulated recall interviews as well as journal reflections. Vygotsky’s Socio-cultural Theory, Ogunniyi’s Contiguity Argumentation Theory and Mavhunga and Rollnick’s Topic-specific Pedagogical Content Knowledge were used as the theoretical lenses in this study. The data gathered were analysed thematically and then categorised into sub-themes and themes. The findings of the study revealed that tapping into the cultural heritage of community members through giving them a voice has great potential to revitalise and indigenise the science curriculum. It also emerged in this study that storytelling is a potential instructional strategy to make science accessible and relevant to learners. The use of the indigenous technology of drum making, drumming, music and dance contributed to the Physics teachers’ agency and empowered them to co-develop their learning and teaching support materials in the form of exemplar lesson plans that integrated IK. Moreover, their pedagogical content knowledge was enhanced through enacting such exemplar lessons and thereafter reflecting on them. The study thus recommends that those in academia should promote the use of indigenous technologies as hubs for mediating the learning of science concepts. It also recommends that learners should be taken out of their science classrooms into the community to learn IK and wisdom from expert community members, something which could assist them in understanding the science taught at school. This might also benefit teachers in effectively implementing the integration of IK in schools and thereby use learners’ cultural heritage as a starting point to enrich meaningful and authentic learning. , Thesis (PhD) -- Faculty of Education, Education, 2022
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  • Date Issued: 2022-10-14

Rural households’ perceptions of an invasive alien species rosa rubiginosa l. (rosehip) and the role it plays in rural livelihoods in Lesotho

  • Authors: Makhorole, Thato Violet
  • Date: 2022-10-14
  • Subjects: Rose hips Lesotho , Invasive plants Lesotho , Rural poor Lesotho , Probit model , Principal components analysis
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/403069 , vital:69919
  • Description: Despite the vast research on the negative impacts of invasive alien species on the environment, these species remain part of the rural communities due to their numerous livelihood uses. Thus, more research is required, focusing mainly on the impacts of invasive alien species on the livelihoods of rural communities. This study investigated the community perceptions of rosehip (Rosa rubiginosa) and its contribution to rural communities as an invasive alien species. Four community councils, Pitseng, Matlameng, Limamarela and Mphorosane in the Leribe District Lesotho, were assessed. The study followed the pragmatism paradigm. The contribution of rosehip to rural livelihoods was analysed by comparing income from rosehip with other income sources. The study used simple random sampling and snowball sampling to select a representative of 160 respondents. The primary data was collected using semi-structured questionnaires. Moreover, SPSS and Stata statistical package programs were used for statistical analyses. The results showed that rosehip's livelihood benefits, its negative impacts, the length of time it has been available in the area, and its abundance highly influence the social, economic and environmental perception of rural communities. Furthermore, the study revealed that although the income from rosehip is extremely low and available for only three months of the year, the income plays an important part to the poorer households who have no other income sources. The study found that the main reason for engagement in rosehip harvesting despite its challenging nature was unemployment. The study also revealed that rosehip is part of the risk-reducing strategy or income diversification. Some households used it to complement other sources of income, such as agricultural production. Rosehip trade, if well-controlled, has the potential to alleviate rural poverty by creating job opportunities, providing a source of household income, and acting as a safety net in the face of shocks such as limited job opportunities and food shortages. In conclusion, households’ perceptions of rosehip have proven that rosehip is a valuable resource that provides a supplementary income that contributes towards alleviating poverty in Lesotho’s rural communities. The study recommends the private sector to establish and manages small agro-processing industries focusing on products used daily. The study also encourages environmental education and indigenous knowledge among community members, which would include knowledge and recognition of invasive alien species and their potential benefits and threats. , Thesis (MEcon) -- Faculty of Commerce, Economics and Economic History, 2022
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  • Date Issued: 2022-10-14
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