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Informal learning in local farming practices by rural women in the Lake Chilwa Basin, Malawi: towards coping and adaptation to climate variability and climate change

  • Authors: Mphepo, Gibson Yadunda
  • Date: 2020
  • Subjects: Women -- Non-formal education - Malawi , Non-formal education -- Malawi , Women -- Malawi -- Social conditions , Crops and climate -- Malawi , Agricultural extension work -- Government policy -- Malawi , Environmental education -- Malawi
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/167540 , vital:41490
  • Description: Evidence reveals that informal learning is a neglected research area, globally and nationally. Informal learning, like formal and non-formal learning, is context specific. In the case of my study, the context was in local maize cultivation and the associated local farming practices which are also neglected. Research has shown that rural women in Malawi are significant change agents in socio-economic sectors, yet they are heavily affected by inequality. For example, extreme weather events of droughts and floods in the Lake Chilwa Basin, disproportionately affect more women than men because of their traditional gendered roles such as home care. The complexity of the dualistic nature of being change agents and victims of injustices at the same time offers a catalytic opportunity for potentially transformative social learning for transformative adaptation. Against this backdrop, I conducted a study to investigate and expand informal learning processes to contribute to building the resilience of women and other community members in Domasi and Nsanama Extension Planning Areas (EPA) within the Lake Chilwa Basin. Specifically, the study answered the following question: “How do drought and inter-seasonal dry spells influence informal learning processes to enable transformation adaptation among rural women cultivating maize in the Lake Chilwa Basin, Malawi?” To address the question, the first stage was to review local farming practices and the associated informal learning processes in Malawi. I then used third generation Cultural Historical Activity Theory (CHAT) as an overarching theoretical framework to guide the subsequent research processes which were split into three main phases: mirror data collection for expansive learning, formative change laboratory workshops, and data analysis and reflection. CHAT is a theoretical framework that helps us comprehend and analyze the relationship between the human mind (i.e. what people think and feel) and activity (what people do). It is a formative and activist learning theory that posits learning as occurring through collective activities to meet or change a common object (Mukute and Lotz-Sisitka, 2012, p. 345). For Koszalka and Wu, 2001(p. 493), within a CHAT framework, knowledge is socially constructed by individual learners, building on existing historical experiences, within the learners’ context. To construct this knowledge, learners use technology or mediating tools, as Vygotsky (1978) calls them. To collect mirror data, I conducted focus group discussions, observation studies, and document analysis. I also conducted key informant interviews with selected extension workers responsible for the two case study sites. The hub of my research constituted change laboratory workshops to expand learning through four of the seven expansive learning actions, namely questioning, analysis, modeling and testing the model. One of the essential procedures I relied on to expand learning during these change laboratory workshops was identification and analysis of contradictions that were mirrored back to women. The use of contradictions as fertile ground for learning is premised on Engstrom’s arguments that contradictions form a catalyst for learning. Data were analysed using two approaches: layered and power relations. A layered analysis is a step-by-step process of understanding a situation from the lower to a higher level (mature stage). For my research, this meant understanding sequential learning from questioning (session 1 – lower level) to testing the model (session 8 – higher level). The second data analysis approach, power relations, relates to the Women Empowerment in Agriculture Index (WEAI), a measure of the degree of women empowerment, their agency and inclusion in farming (Ruth et al., 2013, p. 3). I used this type of power analysis tool because my research was agriculture based. Both data analysis approaches relied on N-vivo which is a form of computer-based qualitative data management software. The software was ideal for my study which was also mostly qualitative. During phase 1 of data collection, I identified five local farming practices associated with local maize cultivation, a focus of my study. These practices were slash and burn (mphanje); traditional insect pest control measures; soil fertility enhancement techniques through kuojeka (crop residue incorporation) and livestock manure; traditional weather forecasts; and multiple cropping (mixed and sequential cropping). Among these, the most preferred by the women I interacted with were kuojeka, livestock manure and mixed cropping. I discovered that these local farming practices are informally learned mainly through word of mouth, observation, trials, women-dominated social networks and drama. I also discovered that some of these informal learning pathways are catalyzed by drought and dry spells. For example, during the 1949 and 2002 drought periods, women reported that they had learned new types of coping strategies such as the use of sawdust and banana root flour in place of maize flour to prepare nsima, a staple food in Malawi. During phase 2, change laboratory workshops, I identified 19 contradictions associated with local farming practices, most of which were related to the Government of Malawi bias towards modern farming practices such as hybrids. Other contradictions were related to traditional structures and norms and religion and traditional beliefs. Solutions were suggested for each of the contradictions. Some of these solutions were tested for their workability. These included setting up diversity blocks (demonstration plots) for local maize cultivation under irrigation and engagement of the youth through WhatsApp groups for the first time at the study sites. The results of the tests show that there is potential to transform local farming practices at the study sites and build social resilience against drought and dry spells. For example, from a local maize demonstration plot in Nsanama Extension Planning Area (EPA), farmers learned that kafula local maize is fast maturing and therefore cushions them against hunger as they wait for the main harvest in later months. Eighty-eight households shared local maize seed harvested from the demonstration gardens for upscaling. The Head of Nsanama EPA had also set up another demonstration garden in 2018-2019 growing season consisting of kafula at Nsanama EPA Headquarters for further informal learning purposes. This research has contributed new knowledge to the existing knowledge base about local farming practices and informal learning. These contributions are in the form of methods I used as well as results obtained. Among the key highlights of my contribution to the knowledge base is the development of scenarios as double stimulation tools for the emerging local farming activity system which emanates from the new model solutions resulting from change laboratory workshops. To the best of my knowledge, this was the first time rural communities were engaged in scenario development in Malawi. The first scenarios of this type were developed in 2010 for the Malawi State of Environment and Outlook Report and the process involved middle to senior managers of various institutions in Malawi. Through historical analysis, my research identified local crops that existed in the past but which are currently non-existent or rare. My study also identified unique local farming practices that even puzzled professionals, including the use of ripe banana peels of makumbuka and sukari to eradicate nansongole grass and native bamboos respectively. Both plant species are considered a nuisance in that they colonize land for cultivation. A breakthrough for radical transformation of local farming practices via informal learning requires development and review of relevant policies in Malawi. Such a process requires evidence. This research has provided background information for this process. For those policies already developed, this research has provided information that can help guide implementation of the generalized list of activities outlined in implementation plans of the respective policies.
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  • Date Issued: 2020

Initiating biological control for Nymphaea mexicana zuccarini (Nymphaeaceae) in South Africa

  • Authors: Reid, Megan
  • Date: 2020
  • Subjects: Nymphaea mexicana zuccarini -- Biological control -- South Africa , Nymphaeaceae -- Biological control -- South Africa , Invasive plants -- Biological control -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/144510 , vital:38352
  • Description: Nymphaea mexicana Zuccarini (Nymphaeaceae) is an aquatic plant originating from south-eastern USA that is becoming increasingly invasive in South Africa as other invasive aquatic plants are being managed successfully through biological control. Mechanical and chemical control of aquatic weeds is expensive, damaging to the environment, and only effective in the short term, so biological control is more desirable as a management strategy for N. mexicana. The biological control of invasive alien plants requires that agents are host specific so that non-target risks are mitigated. For success to be achieved, it is important to ensure that the genetic structure of invasive populations is clarified so that agents can be collected from populations in the native range that match genetically to populations in the invasive range. This is especially important in cases where the morphology of invasive alien plants does not reflect genetic differences between populations. A previous study of the genetic structure of the invasive populations of N. mexicana in South Africa suggests the presence of hybrid forms of the plant in South Africa, with only one of these populations matching with samples from the native range. However, the study only used samples from two sites in the native range using amplified fragment length polymorphisms (AFLPs), so it was necessary to conduct further genetic analyses using samples from more sites in the native range. Hence, the first aim of this study was to develop a better understanding of the genetic structure of N. mexicana populations in the native and invaded range. Genetic samples were collected from sites in the native range during field surveys for potential biological control agents, and inter-simple sequence repeats (ISSRs) were used to compare the genetic structure of invasive and native populations of N. mexicana in South Africa. The results from these analyses suggest that seven of the 14 investigated invasive populations of N. mexicana in South Africa are genetically similar to populations in the native range, while the remaining seven populations are likely to be hybrid forms of the plant. This knowledge will be useful to target populations for biological control and highlights the need for further genetic analyses to determine the parentage of these hybrids so that biological control efforts are more likely to be successful. The initiation of a biological control programme requires that a series of steps are taken in order to maximise the likelihood that this form of intervention will be successful. The first few steps include: identification of the target weed and its genetic structure; exploration in the native range for potential biological control agents; and prioritisation of these agents based on factors such as climatic and genetic compatibility, feeding damage, abundance, and likely host range. Hence, the second aim of this study was to conduct surveys for potential biological control agents in the native range of N. mexicana, and to prioritise these agents. Field surveys were conducted between August and October in 2018 at 17 sites in Florida, Louisiana, and Texas, USA. Sites were selected based on climatic similarity of native sites compared to invasive sites by use of MaxEnt modelling. Native N. mexicana plants were searched for natural enemies, and these were prioritised based on feeding damage, abundance, incidence, and observations of field host range. Two species were prioritised: Bagous americanus LeConte (Coleoptera: Curculionidae) and Megamelus toddi Beamer (Hemiptera: Delphacidae). These species will be imported into quarantine facilities at Rhodes University for host specificity tests to be conducted. Understanding the factors that contribute to the successful establishment of biological control agents is important to improve the efficiency and reduce the costs incurred during the initiation of biological control programmes. Acquiring knowledge of the factors that predict the efficacy of biological control agents is similarly important, and these factors are discussed in the last chapter of this study. The challenges of the biological control of hybrids are also considered, and recommendations are made for the control of N. mexicana and other plants in South Africa.
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  • Date Issued: 2020

Integrating local knowledge when mediating learning of food preservation in a Namibian multicultural Grade 6 class

  • Authors: Shetunyenga, Shetunyenga Fillipus
  • Date: 2020
  • Subjects: Food -- Preservation -- Study and teaching (Elementary) -- Namibia , Ethnoscience -- Study and teaching (Elementary) -- Namibia , Ethnoscience -- Namibia , Education, Elementary -- Namibia , Multicultural education -- Namibia
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/163602 , vital:41052
  • Description: The challenge posed by multicultural classrooms has been acknowledged in many studies. Some scholars believe that the knowledge learners bring to school from their homes or community forms a basis for the knowledge to be acquired at school. That is, if learners’ cultural experiences and/or indigenous knowledge are integrated into teaching of science, learners might make good sense of science. Even though the Namibian National Curriculum has responded well to the calls of recognising and integrating indigeno us knowledge during teaching and learning, it has failed to provide guidance on how this should be done. Therefore, there is a need to minimise the gap between the intention of the National Curriculum and the implementation of this intended curriculum at classroom level. It is against this background that this study sought to investigate whether or not learners’ conceptions and attitudes are influenced by integrating local or indigenous knowledge when teaching food preservation in a Namibian multicultural classroom context. Underpinned by an interpretive paradigm, the study took the form of a mixed-method case study approach. It was conducted at an urban combined school in the Oshana region, Namibia. The sample consisted of 29 Grade 6 learners doing Agricultural Science, the grade 6 Agricultural Science teacher and four community members from different cultural groups. The community members were invited to demonstrate how they culturally preserve mahangu (wheat), fish, milk, and meat in their respective cultures. Data were generated using the pre-and post-intervention questionnaires, a group activity, observations (videotaped lessons) and learners’ journal reflections. Quantitative data from the pre- and post-intervention questionnaires were analysed deductively and presented in tables and graphs. On the other hand, a thematic approach was used to inductively analyse qualitative data, where Vygotsky’s (1978) socio-cultural theory was used as a theoretical lens focusing on culture, mediation, and social interactions. The findings of this study revealed that learners’ conceptions, attitudes, and interest shifted positively as a result of the integration of local or indigenous knowledge on food preservation. Additionally, during the presentations by the community members, learners were actively engaged, asking questions and showing interest in learning about other cultures. The study thus recommends that Agricultural Science or science teachers should, where possible, make efforts to integrate local or indigenous knowledge in their multicultural classrooms.
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  • Date Issued: 2020

Invasion status and impact potential of Florida bass Micropterus floridanus in South Africa

  • Authors: Khosa, Dumisani
  • Date: 2020
  • Subjects: Micropterus floridanus , Florida largemouth bass -- South Africa , Black bass -- South Africa , Micropterus floridanus -- South Africa -- Habitat , Florida largemouth bass -- South Africa -- Habitat , Black bass -- South Africa -- Habitat , Introduced fishes -- Environmental aspects -- South Africa
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/165733 , vital:41276
  • Description: In South Africa, the introduction of alien fishes was largely driven by the development of recreational fishing opportunities. Government-backed programmes resulted in the introduction of four Black Bass species: Micropterus salmoides, Micropterus dolomieu, Micropterus punctulatus and Micropterus floridanus. These species are regarded as the primary threat to native biota and there is an urgent need to assess their spread and impacts. This thesis focuses on: assessing the current distribution of all four Black Basses; using genetic techniques to establish the extent of hybridisation between M. salmoides and M. floridanus, and using functional responses to assess the impact potential of M. salmoides and M. floridanus under the context dependence of temperatures and habitat complexity. Maximum entropy modelling of habitat suitability for Black Bass highlighted that M. salmoides had broad climatic suitability across South Africa, while suitability for M. dolomieu and M. punctulatus was restricted to the Cape Fold Ecoregion. An extensive area-based invasion debt was observed for all Micropterus spp. To better understand the dynamics of hybridisation between M. salmoides and M. floridanus, 38 species-diagnostic single nucleotide polymorphism was used to screen Black Bass populations from the Breede River and Kowie River catchments. Micropterus salmoides alleles were more prevalent than M. floridanus in both the Breede River catchments (69.1% and 30.9%, respectively) and Kowie River catchments (63.3% and 36.7%, respectively). However, isolated populations found in dams (reservoirs) remained free from hybridisation. To compare resource utilisation (i.e. per capita effects) between M. salmoides and M. floridanus, two experimental chapters were designed. Chapter 4 focuses on how temperature mitigates per capita effects between the two Black Basses. There was a significant decrease in per capita effects for M. salmoides with increasing temperatures, while the converse was true for M. floridanus. Chapter 5 gives an account of the influence of habitat complexity on per capita effects. The results showed that habitat complexity did mitigate per capita effects, specifically on M. floridanus, which showed a significant drop in per capita effects; however, no significant difference was recorded for M. salmoides. In the two experimental chapters, M. floridanus exhibited a superior per capita effect compared to M. salmoides, implying higher predation impact on native biota.
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  • Date Issued: 2020

Investigating conceptual teaching of word problems through visualisation processes: a case of selected Grad 9 mathematics teachers

  • Authors: John, Ssennyomo Bernard
  • Date: 2020
  • Subjects: Mathematics -- Study and teaching (Secondary) -- South Africa , Pythagorean theorem -- Study and teaching (Secondary) , Mathematics teachers -- South Africa , Visualization
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/167497 , vital:41486
  • Description: This study investigated how selected grade 9 mathematics teachers used visualisation strategies to conceptually teach Pythagoras' theorem word problems as a result of an intervention program. This research project is an integral component of the ViProMaths project whose goal is to research the effective use of visualisation strategies in the mathematics classroom in the Southern African region. This case study of mathematics teachers in the John Taolo Gaetsewe (JTG) District in the Northern Cape Province, used a social constructivist theory. The study is grounded within an interpretive paradigm and used an explanatory sequential mixed methods design. It surveyed eighty-seven mathematics teachers from all the secondary schools in the JTG District, focusing on their experiences when using visualisation approaches to teach Pythagoras’ theorem word problems. After the survey, three teachers purposively selected from three different schools in the district took part in the intervention programme. I used a survey questionnaire, classroom observations and interviews to collect the data from the study participants. The data were analysed quantitatively and qualitatively. The findings from survey data revealed that while teachers in the JTG District acknowledge the importance and value of visualisation strategies in the teaching of Pythagoras’ theorem word problems, many of them are either using visuals minimally or not using them at all. Challenges such as lack of resources in schools, time constrains, a lack of support from subject advisers, among others were noted. This thus necessitated a need for an intervention with some teachers in the district, specifically focusing on the use of visualisation tools and skills to teach Pythagoras’ theorem word problems for conceptual understanding. Lessons observations showed that all observed teachers used visual models to generate images and used the models to develop mathematical ideas. The teachers used the images to create platforms for classroom discussions. The discussions were driven by questions which teachers asked both for ascertaining learners’ prior knowledge and for finding out if they understood what the teachers were teaching. Interviews revealed that teachers’ perceptions had changed because they now know how to make and use different models to build on learners’ prior knowledge, extend what they are teaching to real life and make sense of Pythagoras’ proposition in multiple ways and to establish connections among a rich set of mathematics concepts when teaching Pythagoras’ theorem word problems. This study concludes that the use of visual strategies has the potential of enhancing conceptual teaching of Pythagoras’ theorem word problems. The implications for teachers are that learners need to be taught how to create visual representations (both internally and externally) of the relations between objects in a word problem as this will help them in maximising understanding. Furthermore, it is hoped that the results of this study could be used by various stake holders who include inter alia, mathematics subject advisers and teacher training institutions to improve the teaching of Pythagoras’ theorem word problems.
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  • Date Issued: 2020

Investigating how teacher leadership can be developed among teachers in a rural school Namibia

  • Authors: Shapange, Laban
  • Date: 2020
  • Subjects: Technical education -- South Africa , Vocational education -- South Africa , Educational leadership -- South Africa , Postsecondary education -- South Africa -- Administration
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/144728 , vital:38374
  • Description: In established democracies, the notion of ‘singular’ school leadership practised by the principal has been challenged and a more expansive approach to leadership, which includes teacher leadership, is now widely accepted. However, in Namibia, as with many countries on the African continent, the idea of ‘singular’ school leadership embedded in the position of principal still prevails. Effective leadership is generally accepted as being core to effective school improvement. The evidence from the school improvement literature constantly highlights that productive leaders exercise an indirect influence on a school’s ability and potential to improve and enhance the achievement of learners. This influence does not necessarily come from senior managers only, but partly lies in the strength of middle level leaders and teachers. Research has shown that when teachers assume shared leadership in the redesign of the school, mentor their colleagues, engage in problem solving at the school level and provide professional growth opportunities for their colleagues, they can be effective in bringing about positive change. These findings triggered my interest to study the potential of this approach to teacher leadership development in Namibia. In this context, this study investigated how teacher leadership can be developed among the teachers in a combined school in rural Namibia. The study examined both the understanding of the concept and the practices of teacher leadership among the teachers and school management team and also aimed at bringing about transformation in their practice. The study was a qualitative case study, which took an interventionist approach, framed by Cultural Historical Activity Theory as the theoretical and analytical framework. In addition, the study also used Grant’s Model of Teacher Leadership as an analytical tool. Eleven teachers and three members of the management team took part in the study as research participants and were selected by means of the purposive sampling method. Data were generated from two different phases. The first phase of the study examined perceptions and practices of leadership, while in the second phase of the study, a series of intervention Change Laboratory Workshops were conducted. Document analysis, observations, focus group interviews and closed-ended questionnaires were used as data gathering tools. The study lasted for a period of six weeks. Data were analysed using inductive and abductive approaches. The main findings of the study revealed that teacher leadership is understood as an ability to influence and inspire both learners and other teachers. Furthermore, although the participants demonstrated an understanding of teacher leadership as a concept, their understanding of teacher leaders’ roles was more on classroom management and control of learners. Teacher leadership development was understood as the process of empowering teachers to take-up various roles and delegated functions through school structures such as committees and within the community. The study further revealed a number of cultural-historic contextual tensions that led to constraints of teacher leadership practice in the case study school. For example, school management team members were seen as a barrier to teacher leadership practice and development. Factors such as limited involvement of teachers in decision-making in the school and lack of school-based continuous professional development programmes for teachers emerged as causes that constrained teacher leadership practice and development in the case study school. The Change Laboratory Workshop findings suggested that in the participants’ view, the revival of the different school committees would especially make a positive contribution to teacher leadership practice and development at the case study school.
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  • Date Issued: 2020

Investigating meaningful and critical teaching of poetry in English First Additional Language: a case of two Grade 11 classrooms in Lusikisiki District, Eastern Cape

  • Authors: Dlamini, Sibongile Melody
  • Date: 2020
  • Subjects: Poetry -- Study and teaching (Secondary) -- South Africa -- Lusikisiki , Second language acquisition , Critical discourse analysis , Literacy -- South Africa -- Lusikisiki , Culturally relevant pedagogy -- South Africa -- Lusikisiki
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/130636 , vital:36449
  • Description: Poetry stands out among literary genres as a rich resource for language teaching and learning (Danesh & Shirkhani, 2015). However, according to some reports on Grade 12 English First Additional Language in the Eastern Cape, poetry is a particularly challenging genre to both teachers and learners. This background has given rise to this study, which aimed to investigate the critical and meaningful teaching of poetry in Grade 11, a class preparing learners for Grade 12. This interpretive qualitative case study drew on Vygotsky’s (1978) socio-cultural theory of cognitive development, which states that learners’ best knowledge is produced when co-operative learning takes place, with the help of the teacher. Purposive sampling was used to select two high schools from Lusikisiki district in the Eastern Cape, and one Grade 11 class and one teacher from each school. Lesson observations, document analysis, semi-structured interviews with the teachers, and focus group discussions with the learners were used to collect data. Cultural-Historical Activity Theory, Critical Discourse Analysis, Dutta’s (2001) model of poetry learning, as well as insights from Vygotsky’s socio-cultural theory were used to analyse data. In addition, Four Reader Roles by Freebody and Luke (1990) were employed as a data analysis tool to find out the degree to which the poetry teaching developed learners into code breakers, text users, text participants and text analysts. The data revealed that both teachers and learners had a limited understanding of and negative attitudes towards poetry, and this affects the way teachers teach as well as how learners learn poetry. It also indicated that a teacher-centred approach constrains meaning and critical poetry teaching and learning. The findings suggested that in place of the traditional way of poetry teaching, teachers need to learn, develop and use innovative teaching strategies to strengthen poetry understanding in learners.
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  • Date Issued: 2020

Investigating visual literacy development through advertisements: a case of Grade 7 English Language Teaching in Mount Frere District, Eastern Cape

  • Authors: Mbuqe, Zolile Patrick
  • Date: 2020
  • Subjects: Visual literacy , English language -- Study and teaching -- Audio-visual aids , Second language acquisition -- South Africa , English language -- Study and teaching -- Activity programs , Advertising -- Study and teaching , Visual learning , English language -- Study and teaching -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/143458 , vital:38248
  • Description: Although the Curriculum and Assessment Policy Statement lists visual literacy as one of the aspects of English First Additional Language in Grades 4-12, many teachers face challenges in teaching it. This study aimed to investigate visual literacy development through advertisements. Drawing on Cultural Historical Activity Theory, this qualitative intervention designed two research phases in which data was collected and analysed. The first phase, a pre-intervention, included lesson observation, analysis of documents and post-lesson semi-structured interviews. Based on Phase One findings and using advertisements as an entry point in developing visual literacy, Phase Two occurred at a change laboratory workshop and engaged eight teachers with the dynamics of meaning making and teaching. This data was analysed using elements of social semiotics and Serafini’s resource practices. The key findings are that despite low visual literacy understanding and practices, rigorous formative intervention indicated advancement in teachers’ understanding of visual literacy. In addition, through this intervention, teachers developed agency in dealing with schooling adversities such as lack of resources and knowledge hence further formative intervention research in visual literacy is recommended for both EFAL subject advisors and teachers.
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  • Date Issued: 2020

Investigation into the influence of an alien plant species on the soil microbiota of the sub-Antarctic, Marion Island

  • Authors: Pienaar, Robert Daniel
  • Date: 2020
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/124039 , vital:35531
  • Description: Embargo applied. Embargo period to expire in April of 2021.
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  • Date Issued: 2020

Investigations into biological control options for Lycium ferocissimum Miers, African Boxthorn (Solanaceae) for Australia

  • Authors: Mauda, Evans Vusani
  • Date: 2020
  • Subjects: Lycium ferocissimum , Solanaceae -- Biological control -- Australia , Weeds -- Control -- Australia , Invasive plants -- Biological control -- Australia , Insects as biological pest control agents -- Australia , Insect-plant relationships
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/167142 , vital:41441
  • Description: Lycium ferocissimum Miers (Solanaceae) (African boxthorn or boxthorn) is a shrub native to South Africa,and has become naturalised and invasive in Australia and New Zealand. The plant is listed on the Noxious Weed List for Australian States and territories. Although other control methods are available, biological control presents a potentially sustainable intervention for reducing populations of this weed in Australia. In South Africa, the plant has been recorded from two allopatric populations, one in the Eastern Cape Province, the other in the Western Cape Provinces, however, there taxonomic and morphological uncertainties are reported in the literature. Therefore, before native range surveys for potential biological control agents could be considered, the taxonomic uncertainty needed to be resolved. The two geographically distinct areas, as well as the Australia population were sampled to assess morphological and genetic variation. All samples collected in Australia were confirmed as L.ferocissimum, with no evidence of hybridisation with any other Lycium species. Nuclear and chloroplast genetic diversity within L.ferocissimum across South Africa was high, and Australia was low, with no evidence of genetic seperation. One ehaplotypes found across Australia was found at only two sites in South Africa, both in the Western Cape, suggesting that the Australian lineage may have originated from this region. Ten samples from South Africa, putatively identified in the field as L.ferocissimum, were genetically characterised as different (unidentified) Lycium species. The majority of plants sampled were confirmed as L.ferocissimum, sharing a common haplotype (haplotype 5) with sampled specimens from Australia. Morphological analyses across different Lycium species in South Africa did not identify any leaf or floral characteristics unique to L.ferocissimum, and thus morphological identification in the native range remains problematic. Surveys for phytophagous in sects on L.ferocissimum were carried out regularly over a two-year period in the two regions. The number of insect species found in the Eastern Cape Province (55) was higher than in the Western Cape Province (41), but insect diversity based on Shannon indices was highest in the Western Cape Province. Indicator species analysis revealed eight insect herbivore species driving the differences in the herbivore communities between the two provinces. Based on insect distribution, abundance, feeding preference and available literature, three species were prioritised as potential biological control agents. These include the leaf-chewing beetles, Cassida distinguenda Spaeth (Chrysomelidae) and Cleta eckloni Mulsant (Coccinellidae), and the leaf-mining weevil, Neoplatygaster serietuberculata Gyllenhal (Curculionidae). Native range studies such as this are perhaps the most technically difficult and logistically time-consuming part of the biological control programme. Yet, the entire outcome of a programme depends on the suite of potential agents feeding on the weed. The information gained during this stage significantly contributed to the prioritization of agents for further host-range testing and possible release. Here we showed how molecular and genetic characterisations of the target weed can be us ed to accurately define the identity and phylogeny of the target species. In addition, the study also highlighted the importance of considering plant morphology and how phenotypic plasticity may influence infield plant identifications while conducting native range surveys. By gaining further information during long-term and wide spread native range surveys we were not just able to provide a list of herbivorous insect fauna and fungi associated with the plant, but were able to prioritise the phytophagous species that held the most potential as biological control agents.
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  • Date Issued: 2020

IsiXhosa as the language of teaching and learning mathematics in Grade Six: investigating the mother tongue based bilingual education mathematics pilot in the Eastern Cape Province, South Africa

  • Authors: Mbude, Naledi Ntombizanele
  • Date: 2020
  • Subjects: Mathematics -- Study and teaching (Elementary) -- South Africa , Education, Bilingual -- South Africa , Native language and education -- South Africa , Language policy -- South Africa
  • Language: English
  • Type: text , Thesis , Doctoral , PHD
  • Identifier: http://hdl.handle.net/10962/143262 , vital:38215
  • Description: This study is an investigation on lessons learnt when the language of learners is maintained for teaching and learning mathematics beyond Grade 3 for another 3 years. It is undertaken in Cofimvaba, a rural village of the Eastern Cape in South Africa. We investigate lessons that can be learnt from the Mother Tongue based- Bilingual Education (MTbBE) strategy, that can be replicated. South Africa post-1994 has a Language-in-Education Policy (1997) that provides for the use of all official languages as Languages of Teaching and Learning (LoLT), this has remained on paper as the schooling system focusses on an early –exit model of three years of the Mother Tongue Education (MTE) for the Foundation Phase (FP) then exit to English instruction in Grade 4; this applies to African language learners only. English and Afrikaans speakers have mother tongue education from cradle to university; a benefit they have enjoyed pre- and post-apartheid. Various studies have been conducted to understand the relationship between language and mathematics learning as it is crucial to design mathematics instruction for students who are English Learners (ELs) and/or bilingual. However, in South Africa, there had not been a direct exploration of the achievement of learners in mathematics when their mother tongue is used and sustained throughout the first six years of learning mathematics, while English is a supportive resource. This is the focus of this study. The study lends itself to the adoption of a mixed methods design (QUALT+QUANT), while also employing documents, observation and test scores of learners to obtain data. Content analysis and thematic analysis approaches were used in analyzing the qualitative-type data while a statistical approach was used in the analysis of quantitative data. The main aim of the study was to establish whether in the Cofimvaba pilot, there is any evidence to make a case for extending Mother Tongue Based-bilingual Education (MTBBE) beyond Grade 3 for black African children. Another aim, was to highlight and document the effort that was the first of its kind in South Africa, undertaken in a small rural area to develop isiXhosa as language of Mathematics and Science. The most salient of this effort was the fact that it was underpinned by deliberate theoretical and empirical foundations central to language policy and planning. The finding of this study is that the use of isiXhosa for MTbBE was effective for boosting mathematical and science skills in the mother tongue and English in Grade 6 as demonstrated in Chapter 7 and 8. Lastly, this study demonstrates the power of political will and how a decision backed by financial investment can transform the wider system despite the challenges of transformation. For the first time in the history of education; a poor department has stuck to its guns; unwearied by the negativity surrounding the development of African languages. It committed to the cause of improving the academic achievement of the poorest of the poor. Historically, in implementing a Mathematics Curriculum, the Department of Education (both officials and teachers) has never efficiently implemented the LiEP (1997) in the manner spelt out in its policy documents viz, multilingualism as the norm. The focus has been on a perspective of learners who are learning and must English, then mathematics and ways to get them to know English at all costs. This view creates inequities in the classroom because it places emphasis on what learners don’t know or can’t do. In contrast, this study proposes a sociocultural perspective that shifts away from deficiency models of bilingual learners and instead focuses on describing the resources bilingual students use to communicate mathematically (Moskovich, 1988). Without this shift we will have a limited view of these learners and will design instruction that neglects the competencies they bring to mathematics classrooms. If, instead, we learn to recognize the mathematical ideas these students express in spite of their accents, code-switching, or missing vocabulary, then instruction can build on students’ competencies and resources (Moskovich, 1998). This study recommends a plethora of strategies that must be taken by the Department of Education to widen epistemological access to mathematics for African language learners using MTbBE as a viable strategy.
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  • Date Issued: 2020

It's my hand that wrote!

  • Authors: Magade, Mncedi
  • Date: 2020
  • Subjects: South African fiction (English) -- 21st century
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/142551 , vital:38090
  • Description: This collection of short stories experiments with the idea of the text as it constitutes the world just as much as it is constituted by the world. These short stories use the text as a way to respond to struggles faced by people whose identities do not conform to society’s standards. The stories in here navigate between fantastic and experiential writing which allows the text to speak in its own language. The writing is influenced by that of Mthuthuzeli Matshoba for the realist approach in telling the stories. Ayi Kwei Armah’s writing in Fragments for experientialism that focuses on the dead and the living and which makes specific references to the idea of home – particularly for those who always find it hard to belong. And that of Bruce Sterling’s creation of explosive imagery in science fiction that sticks in the reader’s mind as portrayed in his short story we see things differently. Angela Carter’s brilliance in writing short stories and her approach to magical realism has also been a powerful influence. In telling these stories using a hybrid/fluid approach, I hope to come to terms with being a different “being”. It is to find ways of telling myself that it is okay to be queer, that to be a misfit is no sin. To say this in a language that gives meaning to my own struggles of being. This work is a combination of three disjointed moments of the narrator’s life experiences which are exposed in three sections; It’s My Hand That Wrote, (Un)Tying The Knot and Thoughts. The aim of creating these three moments is to let the reader dive a variety of “truths” of the narrator’s life, instead of aiming to achieve a coherent single “Truth” about one’s life. It’s My Hand That Wrote explores both the unusual and inconsistency of life in a chaotic but explorative fashion.
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  • Date Issued: 2020

Johannesburg as dystopia: South African science fiction as political criticism

  • Authors: Kirsten, Ashton Lauren
  • Date: 2020
  • Subjects: Science fiction, South African -- History and criticism , Johannesburg (South Africa) -- Fiction , Science fiction films -- History and criticism , Dystopias in literature , Dystopian films , Politics in literature , Politics in motion pictures , Beukes, Lauren -- Zoo City , Blomkamp, Neill, 1979- -- Chappie , Miller, Andrew K., 1974 or 1975- -- Dub steps
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/147671 , vital:38659
  • Description: This thesis will interrogate the spatial dynamics and configurations of one of the country’s most prominent cities: Johannesburg. Johannesburg has been, and continues to be, a central focus in the nation’s imaginary. There is a trend within South African science fiction (sf) – both literature and film – to portray Johannesburg as a dystopian, post-law, poverty-stricken space as a means of conceptualising the socioeconomic situation within the country. This study will isolate Johannesburg-based works of sf and interrogate why authors and filmmakers disproportionately return to this setting. Investigated are three contemporary works, namely, Zoo City (2010) by Lauren Beukes, Neill Blomkamp’s film, Chappie (2015), and Dub Steps (2015) by Andrew Miller. This study explores the ways in which South African works of sf serve as social and political critique in the post-apartheid era of financial disparity, the formation of new boundaries, divisions of space and privilege, and the dereliction of critical infrastructure. The primary methodology of this thesis is that of Marxist literary analysis (specifically with reference to Louis Althusser’s theoretical models), which will be conducted alongside discussions of authentic history of the country as well as political developments in order to illustrate how South African sf critically engages with, and succinctly critiques, its context. The aesthetics of African sf are inseparable from the politics of the past and the current moment and through the aesthetics of the future, South Africans can reimagine the politics of the now. This study therefore also revisits a selection of non-sf Johannesburg-set novels published post-1925 and argues that these texts can be studied as early examples of South African dystopian writing. In doing so, this study illustrates that dystopian writing about and in South Africa is not an advent of the 21st century, but an extension of a long history of critical engagement. This thesis suggests that the dystopian genre is helpful in reframing the issues of the present (and the past) so that some form of meaningful change is theorized. The underlying impulse of dystopian cultural production is ultimately hopeful: a worse context is imagined to warn society of its follies so that these shortcomings and issues can be corrected, thereby avoiding the disastrous world(s) portrayed in the fiction. In this way, this study contends that local sf should not be inextricably linked to the melancholia that thoughts of dystopia bring about. Rather, the nuanced criticism contained within these dystopian texts is testament to the country’s ever-enduring spirit of change and transformation.
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  • Date Issued: 2020

Journeying home, exile and transnationalism in Noni Jabavu and Sisonke Msimang’s memoirs

  • Authors: Masola, Athambile
  • Date: 2020
  • Subjects: Home in literature , Exile (Punishment) in literature , Women authors, Black -- South Africa -- History and criticism , Jabavu, Noni -- Criticism and interpretation , Msimang, Sisonke -- Criticism and interpretation
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/166529 , vital:41376
  • Description: This thesis examines the memoirs of two South Africa female writers: Noni Jabavu and Sisonke Msimang. In analysing their memoirs, this thesis sets out to contribute to the scholarship which centres the voices of Black women writers. It explores how both writers interrogate the concepts of home, exile and transnationalism. My focus is on the ways in which the writers theorise questions of belonging, and the extent to which their writing provides the opportunity to give voice to the complex nature of belonging. I read the narratives from these two writers alongside each other, as Noni Jabavu is Sisonke Msimang’s literary ancestor. By looking at their works alongside each other, this thesis becomes an intergenerational conversation between the past and the present. Using Black feminist thought and migratory subjectivity, this thesis examines the ways in which these writers connect the personal and the political. Noni and Sisonke navigate the private spaces of home in conversation with the political experience of exile and the nation. In the second chapter, I explore home as ekhaya, isizwe and an imaginary homeland. Ekhaya is the isiXhosa word denoting the family home, where there is a network of family rather than a nuclear family. Home is also isizwe: the isiXhosa word which evokes the nation state, which takes on layered meanings in the context of colonialism and apartheid. Home can also be an imaginary homeland, which is an imagined version of home after a long absence such as exile. In the third chapter, I examine three forms of exile: internal exile, estrangement and political exile. Finally, in chapter four, I analyse transnationalism: a border-crossing which raises questions of power, mobility and kinship. Looking at home, exile and transnationalism together allows for an exploration which challenges taken-for-granted ideas about place and identity. These memoirs illuminate the ways in which Black women constitute and reconstitute their identities according to the places which they access through travel.
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  • Date Issued: 2020

Learning about volunteering: an exploration of literacy volunteers' experiences

  • Authors: Yendall, Kaitlin Amy
  • Date: 2020
  • Subjects: Literacy -- Study and teaching -- South Africa , Literacy programs -- South Africa , Voluntarism -- South Africa , Volunteer workers in community development -- Training of , Service learning , Language and education -- South Africa , Language arts (Primary) , English language -- Study and teaching (Elementary) , Volunteer workers in Education -- Training of
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/138336 , vital:37623
  • Description: After almost 25 years of democracy in South Africa, not everyone has access to the same quality education. The responsibility of creating a literate society however cannot rely on the national government and schools alone, but instead needs to fall on the shoulders of various stakeholders. Volunteers in particular have an important role to play in remedying the current literacy crisis experienced in South Africa. This study takes the form of a case study approach and examines the experiences of Project Read literacy volunteers. A telephonic survey and two focus group discussions were conducted in order to determine who it is that volunteers for the programme; what prompts these particular individuals to volunteer; the perceived benefits of volunteering; and how volunteers report on their volunteering experiences. Although the Project Read programme is focused on the early literacy development of learners, volunteers seemed to undergo a developmental process themselves – something they had not anticipated at the start of their volunteering journey. This study illustrates the power of meaningful relationships in breaking down artificial categories and in bringing about important change with regards to the perceptions and attitudes of individuals towards community engagement. It is hoped that the data generated through this study will assist in recruiting and retaining more literacy volunteers through feedback to the NGO. In this way more children will be assisted to enhance their literacy competencies, from which they can build and achieve.
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  • Date Issued: 2020

Macro-locational determinants and motive of Chinese foreign direct investment in Cameroon

  • Authors: Andangnui, Quintabella
  • Date: 2020
  • Subjects: Investments, Foreign -- Cameroon , Investments, Chinese -- Cameroon , Corporations, Foreign -- Cameroon , Industrial location -- Cameroon
  • Language: English
  • Type: text , Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10962/163157 , vital:41014
  • Description: This research falls under the general themes of macro-locational determinants and motives of Foreign Direct Investment (FDI) and the challenges faced by FDIs. Specifically, the research focuses on macro-locational determinants of FDI and the motives of Chinese FDI in Cameroon, and the challenges faced by Chinese FDI in Cameroon. This research is motivated by China’s interest in African countries as well as the reciprocal interest in Chinese FDI by African countries, especially Cameroon. While various FDI theories and previous empirical studies indicate that macro-locational determinants of FDI constitute a country’s principal comparative advantage to attract FDI, there is still no universally acceptable set of macro-locational determinants of FDI. Furthermore, some empirical studies assert that Chinese FDI does not follow conventional FDI theories or western approaches to FDI, especially when investing in African countries. It is suggested that some widely accepted macro-locational determinants of FDI are frequently ignored by Chinese FDI. While FDI theories identify four motives for FDI (resource-, market-, efficiency-, and strategic asset-seeking) as the main motives for investing in a foreign country, the motives for Chinese FDI, especially in Africa, have been questioned by some scholars, the media and politicians, due to the significant but seemingly counterintuitive investments made by Chinese state-owned FDI in politically unstable resource-rich African countries. Furthermore, differences in the motives of Chinese privately owned and state-owned firms identified in previous empirical studies have raised concerns, particularly regarding the motives of state-owned Chinese firms in Africa which suggest a stance of neo-colonialism by Chinese state-owned FDI. The research aims to identify the significant macro-locational determinants of Chinese FDI in Cameroon, to provide clarity on the motives of Chinese FDI and to identify the challenges faced by Chinese FDI in Cameroon. To achieve the aim of this research, hypothetical relationships based on FDI theory and previous empirical research were formulated between Chinese FDI and the proposed macro-locational determinants of FDI and the four identified motives of FDI. In this research, a positivist research paradigm using quantitative methods was followed. Accordingly, the research design and methodology was underpinned by the positivist paradigm. A descriptive and analytical survey methodology was utilised, using both primary and secondary data sources. Secondary data was collected from reliable and credible databases for the period 2004 to 2018 to generate a time series to test the hypothetical relationships pertaining to the macro-locational determinants of Chinese FDI in Cameroon. To test the hypothetical relationships pertaining to the motives of Chinese FDI and to identify the challenges of Chinese FDI in Cameroon, primary data was collected by means of a questionnaire using convenience and snowball sampling techniques. The validity of the findings on the macro-locational determinants of FDI was confirmed through unit root and cointegration tests. Confirmatory Factor Analysis (CFA) and Cronbach’s alpha coefficients were used to ensure the validity and reliability of the findings on the motives of FDI. To assess the hypothetical relationships on the motives for Chinese FDI, the hypothetical relationship on the macro-locational determinants of FDI was determined using Ordinary Least Square (OLS) regression, t-tests, one-way ANOVA, descriptive statistics and logistic regression. In addition, descriptive statistics were used to analyse the data on the challenges of Chinese FDI. The findings indicated that the main macro-locational determinants of Chinese FDI in Cameroon included market size, political risk, limited trade openness, real effective exchange rate, interest rate and human capital. The findings also indicated that market-seeking constitutes the main motive of privately owned Chinese FDI in Cameroon. The findings also indicated that the top four challenges faced by Chinese FDI in Cameroon include corruption, the ambiguity of the legal system of Cameroon, the difficulty to negotiate with government and privatisation officials and high levels of taxes. The findings of this research serve as a test of theory, given that they determine whether the macro-locational determinants identified from FDI theories are also significant macro-locational determinants of Chinese FDI. Furthermore, the findings have the potential to assist in policy formulation aimed at encouraging Chinese FDI into Cameroon. The findings could also assist the Cameroonian government to allocate national resources efficiently by prioritising identified macro-locational determinants. The findings provide clarity on the motives of Chinese FDI in Cameroon and could assist the government to negotiate better deals that may enable Cameroon to benefit optimally from Chinese FDI.
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  • Date Issued: 2020

Making South African tertiary education multilingual: the implementation, monitoring and evaluation of SANTED Multilingualism Projects 2007 – 2010

  • Authors: Nosilela, Bulelwa
  • Date: 2020
  • Subjects: South Africa-Norway Tertiary Education Development Programme , Language policy -- South Africa , Multilingual education -- South Africa , Language and education -- South Africa , Education, Higher -- Social aspects -- South Africa
  • Language: English
  • Type: text , Thesis , Doctoral , PHD
  • Identifier: http://hdl.handle.net/10962/140513 , vital:37895
  • Description: This thesis focuses on multilingualism as it applies to education, particularly higher education in South Africa. The thesis suggests that language must be seen as critical in education (Obanya, 2004; Wolff, 2006). This thesis also suggests that there is a link between a person’s general competence in an educational environment, and that person’s language competence. In support of other scholars, this thesis also finds that learners from low social classes in society have a restricted linguistic code and therefore the learners from these social classes lack the ability to express themselves in an elaborative manner in a cognitive situation while learners from upper social class have an elaborate linguistic repertoire in the language of instruction, namely English. Even though general policy in South Africa and Africa as a whole recognises this relationship between language and education, this thesis finds that very little is being done to implement these well-meaning policies. The SANTED (South Africa-Norway-Tertiary-Education) programme, which forms the focus of this thesis, is seen as an exception. While there is an increase in the number of learners and students accessing centres of learning, especially those from historically-disadvantaged backgrounds (CHE Higher Education Monitor, 2008), there is at the same time rigorous debate in South Africa at the moment as to whether these learners and students benefit optimally from knowledge offered in centres of learning, and are therefore, not accomplishing success expected from them (Boughey, 2008). This thesis suggests that at the centre of this debate is the understanding that, while there are a variety of factors that might affect their success, for example social and economic status, schooling background in case of students in higher education, language plays a pivotal role. This thesis analyses the challenges and successes which faced the SANTED programme at a number of South African institutions where language issues were brought to the centre of the learning process. The thesis also assesses best practices in various African countries and makes recommendations regarding language-use in Higher Education, as part of a transformationprocess. The collaboration between the South African and Norwegian governments provided impetus to policy implementation. It also had other focus areas such as capacity building, access, success and retention and collaboration with Southern African Developing Countries (SADC). This thesis shows, through a critical analysis of SANTED, that it represented an important intervention regarding the promotion of multilingualism.
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  • Date Issued: 2020

Managing the invasive aquatic plant Sagittaria platyphylla (Engelm.) J.G. Sm(Alismataceae): problems and prospects

  • Authors: Ndlovu, Mpilonhle Sinothando
  • Date: 2020
  • Subjects: Aquatic weeds -- Biological control -- South Africa , Sagittaria latifolia -- Biological control -- South Africa , Noxious weeds -- Biological control -- South Africa , Invasive plants -- Biological control -- South Africa , Listronotus , Insects as biological pest control agents
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/167121 , vital:41439
  • Description: Sagittaria platyphylla (Engelm.) J.G.Sm. (Alismataceae), commonly known as Delta arrowhead, is an invasive aquatic macrophyte native to southern United States of America (USA) that has become a serious weed in freshwater systems in South Africa, New Zealand, Australia, and recently China. In South Africa, the plant was first detected in Krantzkloof Nature Reserve, KwaZulu-Natal Province in 2008, and due to its known impact in other countries, it was listed as a Category 1a invader species under the National Environmental Management: Biodiversity Act 2004 (NEM: BA). This listing required mechanical and chemical control methods to be implemented by the South African National Biodiversity Institute’s (SANBI), Invasive Species Programme (ISP), with the aim of eradicating the weed. Despite the eradication efforts, by 2016, the weed was recognized as one of the country’s top 10 worst and fastest spreading invasive alien plants. Since its introduction in 2008, the plant has spread both within and between sites in South Africa, increasing from one site in 2008 to 72 sites by 2019. Once introduced into lotic systems, the plant spread rapidly downstream, in some cases up to 120km within six years, with an average of 10 km per year. Extirpation over the last ten years was only possible at a limited number of sites. Under the current management approach, the invasion is foreseen to spread to new sites within a 5 km radius of the current populations. Due to the failure of conventional control mechanisms, biological control is currently being considered as a potential control option. Four potential biological control agents are under investigation, but none have been released. Amongst them is the fruit and flower feeding weevil Listronotus appendiculatus Bohm. (Coleoptera: Curculionidae) which showed most potential as a suitable biological control agent. This study demonstrated that L. appendiculatus herbivory negatively influenced the overall fitness of S. platyphylla by reducing the plant’s growth rate and above ground biomass. Listronotus appendiculatus herbivory also reduced the plant’s size and the potential to kill adult plants. Most importantly, L. appendiculatus larval feeding damage significantly reduce viable-germinating seeds, the weed’s primary dispersal mechanism. Therefore, a biological control programme is advised to be integrated within the current management plan.
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  • Date Issued: 2020

Market timing and portfolio returns: an empirical analysis of the potential profitability of buy-sell strategies, based on South African equities 2009-2018

  • Authors: Mulweli, Ramulongo
  • Date: 2020
  • Subjects: Johannesburg Stock Exchange , Stocks -- Charts, diagrams, etc. , Investment analysis -- South Africa , Stocks -- South Africa , Stocks -- South Africa -- Cast studies
  • Language: English
  • Type: text , Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10962/144487 , vital:38350
  • Description: South Africa’s financial markets have become larger and more complex over recent decades. The number of market participants who are using technical analysis techniques to predict the market’s movement has been growing rapidly. This research aims to investigate if historical share prices can be used when forecasting the market’s direction and to examine the profitability of the Japanese candlestick patterns. The study is based on ten companies selected from the JSE top 40 2019 composition. These are Aspen Pharmacy Holding, Capitec Bank Holding LTD, Discovery LTD, Kumba Iron Ore LTD, Mondi PLC, Mr. Price Group LTD, MTN Group LTD, Naspers LTD, SASOL LTD, and Shoprite Holdings LTD. These were selected from the JSE top 40 based on market capitalization and sector. This research analyzes eight candlestick reversal patterns; four are bullish patterns namely: doji star, hammer, bullish engulfing and the piercing lines and the other four are bearish patterns namely: shooting star, hanging man, bearish engulfing and the dark cloud cover. The ARCH and GARCH models are used to test for correlation between past share prices and future share prices and the binomial test and the mean return calculations were used to test the profitability of candlestick patterns. The sample is from Thomson DataStream 2019 and IRESS SA 2019 and covers ten years with 2496 observations starting from 02 January 2009 to 31 December 2018. The findings from the ARCH and GARCH tests revealed that there is a serial correlation between the returns from the previous day and the returns for the current day. The results from the mean returns and the binomial tests show strong evidence that the shooting star, hanging man, bearish engulfing and the bulling engulfing are statistically significant in predicting the share price movements. On the other hand, there was no evidence that the dark cloud cover, piercing lines, and the bullish doji can predict share price movements. Additionally, further studies on this topic could be improved by adding different candlestick patterns and the total number of companies analyzed. The results could also be improved by analyzing the candlestick reversal patterns when they are used with other trading rules such as support resistance levels and oscillators.
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  • Date Issued: 2020

Mechanism of action of non-synonymous single nucleotide variations associated with α-carbonic anhydrases II, IV and VIII

  • Authors: Sanyanga, T. Allan
  • Date: 2020
  • Subjects: Carbonic anhydrase , Carbonic anhydrase -- Therapeutic use , Nucleotides
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/167346 , vital:41470
  • Description: The carbonic anhydrase (CA) group of enzymes are Zinc (Zn2+) metalloproteins responsible for the reversible hydration of CO2 to bicarbonate (BCT or HCO− 3 ) and protons (H+) for the facilitation of acid-base balance and homeostasis within the body. Across all organisms, a minimum of six CA families exist, including, α (alpha), β (beta), γ (gamma), δ (delta), η (eta) and ζ (zeta). Some organisms can have more than one family, with exception to humans that contain the α family solely. The α-CA family comprises of 16 isoforms (CA-I to CA-XV) including the CA-VIII, CA-X and CA-XI acatalytic isoforms. Of the catalytic isoforms, CA-II and CA-IV possess one of the fastest rates of reaction, and any disturbances to the function of these enzymes results in CA deficiencies and undesirable phenotypes. CA-II deficiencies result in osteopetrosis with renal tubular acidosis and cerebral calcification, whereas CA-IV deficiencies result in retinitis pigmentosa 17 (RP17). Phenotypic effects generally manifest as a result of poor protein folding and function due to the presence of non-synonymous single nucleotide variations (nsSNVs). Even within the acatalytic isoforms such as CA-VIII that llosterically regulates the affinity of inositol triphosphate (IP3) for the IP3 receptor type 1 (ITPR1) and regulates calcium (Ca2+) signalling, the presence of SNVs also causes phenotypes cerebellar ataxia, mental retardation, and dysequilibrium syndrome 3 (CAMRQ3). Currently the majority of research into the CAs is focused on the inhibition of these proteins to achieve therapeutic effects in patients via the control of HCO− production or reabsorption as observed in glaucoma and diuretic medications. Little research has therefore been devoted into the identification of stabilising or activating compound that could rescue protein function in the case of deficiencies. The main aim of this research was to identify and characterise the effects of nsSNVs on the structure and function of CA-II, CA-IV and CA-VIII to set a foundation for rare disease studies into the CA group of proteins. Combined bioinformatics approaches divided into four main objectives were implemented. These included variant identification, sequence analysis and protein characterisation, force field (FF) parameter generation, molecular dynamics (MD) simulation and dynamic residue network analysis (DRN). Six variants for each of the CA-II, CA-IV and CA-VIII proteins with pathogenic annotations were identified from the HUMA and Ensembl databases. These included the pathogenic variants K18E, K18Q, H107Y, P236H, P236R and N252D for CA-II. CA-IV included the pathogenic R69H, R219C and R219S, and benign N86K, N177K and V234I variants. CA-VIII included pathogenic S100A, S100P, G162R and R237Q, and benign S100L and E109D variants. CA-II has been more extensively studied than CA-IV and CA-VIII, therefore residues essential to its function and stability are known. To discover important residues and regions within the CA-IV and CA-VIII proteins sequence and motif analysis was performed across the α-CA family, using CA-II as a reference. Sequence analysis identified multiple conserved residues between the two acatalytic CA-II and CA-IV, and the acatalytic CA-VIII isoforms that were proposed to be essential for protein stability. With exception to the benign N86K CA-IV variant, none of the other pathogenic or benign CA-II, CA-IV and CA-VIII SNVs were located at functionally or structurally important residues. Motif analysis identified 11 conserved and important motifs within the α-CA family. Several of the identified variants were located on these motifs including K18E, K18Q, H107Y and N252D (CA-II); N86K, R219C, R219S and V234I (CA-IV); and E109D, G162R and R237Q (CA-VIII). As there were no x-ray crystal structures of the variant proteins, homology modelling was performed to calculate the protein structures for characterisation. In CA-VIII, the substitution of Ser for Pro at position 100 (variant S100P) resulted in destruction of the β-sheet that the SNV was located on. Little is known about the mechanism of interaction between CA-VIII and ITPR1, and residues involved. SiteMap and CPORT were used to identify binding site amino for CA-VIII and results identified 38 potential residues. Traditional FFs are incapable of performing MD simulations of metalloproteins. The AMBER ff14SB FF was extended and Zn2+ FF parameters calculated to add support for metalloprotein MD simulations. In the protein, Zn2+ was noted to have a charge less than +1. Variant effects on protein structure were then investigated using MD simulations. Root mean square deviation (RMSD) and radius of gyration (Rg) results indicated subtle SNV effects to the variant global structure in CA-II and CA-IV. However, with regards to CA-VIII RMSD analysis highlighted that variant presence was associated with increases to the structural rigidity of the protein. Principal component analysis (PCA) in conjunction with free energy analysis was performed to observe variant effects on protein conformational sampling in 3D space. The binding of BCT to CA-II induced greater protein conformational sampling and was associated with higher free energy. In CA-IV and CA-VIII PCA analysis revealed key differences in the mechanism of action of pathogenic and benign SNVs. In CA-IV, wild-type (WT) and benign variant protein structures clustered into single low energy well hinting at the presence of more stable structures. Pathogenic variants were associated with higher free energy and proteins sampled more conformations without settling into a low energy well. PCA analysis of CA-VIII indicated the opposite to CA-IV. Pathogenic variants were clustered into low energy wells, while the WT and benign variants showed greater conformational sampling. Dynamic cross correlation (DCC) analysis was performed using the MD-TASK suite to determine variant effects on residue movement. CA-II WT protein revealed that BCT and CO2 were associated with anti-correlated and correlated residue movement, highlighting at opposite mechanisms. In CA-IV and CA-VIII variant presence resulted in a change to residue correlation compared to the WT proteins. DRN analysis was performed to investigate SNV effects of residue accessibility and communication. Results demonstrated that SNVs are associated with allosteric effects on the CA protein structures, and effects are located on the stability assisting residues of the aromatic clusters and the active site of the proteins. CA-II studies discovered that Glu117 is the most important residue for communication, and variant presence results in a decrease to the usage of the residue. This effect was greatest in the CA-II H107Y SNV, and suggests that variants could have an effect on Zn2+ dissociation from the active site. Decreases to the usage of Zn2+ coordinating residues were also noted. Where this occurred, compensatory increases to the usage of other primary and secondary coordination residues were observed, that could possibly assist with the maintenance of Zn2+ within the active site. The CA-IV variants R69H and R219C highlighted potentially similar pathogenic mechanisms, whereas N86K and N177K hinted at potentially similar benign mechanisms. Within CA-VIII, variant presence was associated with changes to the accessibility of the N-terminal binding site residues. The benign CA-VIII variants highlighted possible compensatory mechanisms, whereby as one group of N-terminal residues loses accessibility, there was an increase to the accessibility of other binding site residues to possibly balance the effect. Catalytically, the proton shuttle residue His64 in CA-II was found to occupy a novel conformation named the “faux in” that brought the imidazole group even closer to the Zn2+ compared to the “in” conformation. Overall, compared to traditional MD simulations the incorporation of DRN allowed more detailed investigations into the variant mechanisms of action. This highlights the importance of network analysis in the study of the effects of missense mutations on the structure and function of proteins. Investigations of diseases at the molecular level is essential in the identification of disease pathogenesis and assists with the development of specifically tailored and better treatment options especially in the cases of genetically associated rare diseases.
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  • Date Issued: 2020
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