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VIVA Comrade Moss

  • Authors: NUMSA
  • Date: 25 April
  • Subjects: NUMSA
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/109640 , vital:33163 , SALHA 14b : NUMSA
  • Description: The last 'Trial Update" reported on Comrade Moss’s case until mid-March. This report covers the period from that time up until 25th April.STADLER - "ANC EXPERT" Brigadier Stadler testified that the ANC had made certain calls to organisations within the country which, according to his "research", had been followed by organisations in the country. As examples he gave the ANC’s call for ungovernability, the formation of organs of people’s power and the destruction of town councils. During cross-examination Stadler conceded that he was not able to give examples of any direct link between the ANC and organisations inside the coutry but he said an inference could be drawn by looking at the ANC’s call and the behaviour of organisations inside the country.
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  • Date Issued: 25 April

The prevalence of insufficient iodine intake in pregnancy in Africa: Protocol for a systematic review and meta-analysis

  • Authors: Charles Bitamazire Businge , Benjamin Longo-Mbenza , Andre Pascal Kengne
  • Date: 22-8-2019
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/11260/3387 , vital:43338 , https://systematicreviewsjournal.biomedcentral.com/articles/10.1186/s13643-019-1092-7#citeas
  • Description: Background: Insufficient iodine intake in pregnancy is associated with many adverse pregnancy outcomes. About 90% of African countries are at risk of iodine deficiency due to poor soils and dietary goitrogens. Pregnancy predisposes to insufficient iodine nutrition secondary to increased physiological demand and increased renal loss. Iodine deficiency is re-emerging in countries thought to be replete with pregnant women being the most affected. This review seeks to identify the degree of iodine nutrition in pregnancy on the entire African continent before and after the implementation of national iodization programmes. Methods: A systematic search of published literature will be conducted for observational studies that directly determined the prevalence of insufficient iodine intake among pregnant women in Africa. Electronic databases and grey literature will be searched for baseline data before the implementation of population-based iodine supplementation and for follow-up data up to December 2018. Screening of identified articles and data extraction will be conducted independently by two investigators. Risk of bias and methodological quality of the included studies will be assessed using a risk of bias tool. Appropriate meta-analytic techniques will be used to pool prevalence estimates from studies with similar features, overall and by major characteristics including the region of the study, time period (before and after implementation of iodization programmes), sample size and age. Heterogeneity of the estimates across studies will be quantified and publication bias investigated. This protocol is reported according to Preferred Reporting Items for Systematic reviews and Meta-Analysis protocols (PRISMA-P) 2015 guidelines. Discussion This review will help ascertain the impact of national iodization programmes on the iodine nutrition status in pregnancy in Africa and advise policy on the necessity for monitoring and mitigating iodine deficiency in pregnancy in Africa. This review is part of a thesis that will be submitted to the Faculty of Health Sciences, University of Cape Town, for the award of a PhD in Medicine whose protocol has been granted ethics approval (UCT HREC 135/2018). In addition, the results will be published in a peer-reviewed journal.
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  • Date Issued: 22-8-2019

A decision-making model to guide securing blockchain deployments

  • Authors: Cronje, Gerhard Roets
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/10962/188865 , vital:44793
  • Description: Satoshi Nakamoto, the pseudo-identity accredit with the paper that sparked the implementation of Bitcoin, is famously quoted as remarking, electronically of course, that “If you don’t believe it or don’t get it, I don’t have time to try and convince you, sorry” (Tsapis, 2019, p. 1). What is noticeable, 12 years after the famed Satoshi paper that initiated Bitcoin (Nakamoto, 2008), is that blockchain at the very least has staying power and potentially wide application. A lesser known figure Marc Kenisberg, founder of Bitcoin Chaser which is one of the many companies formed around the Bitcoin ecosystem, summarised it well saying “…Blockchain is the tech - Bitcoin is merely the first mainstream manifestation of its potential” (Tsapis, 2019, p. 1). With blockchain still trying to reach its potential and still maturing on its way towards a mainstream technology the main question that arises for security professionals is how do I ensure we do it securely? This research seeks to address that question by proposing a decision-making model that can be used by a security professional to guide them through ensuring appropriate security for blockchain deployments. This research is certainly not the first attempt at discussing the security of the blockchain and will not be the last, as the technology around blockchain and distributed ledger technology is still rapidly evolving. What this research does try to achieve is not to delve into extremely specific areas of blockchain security, or get bogged down in technical details, but to provide a reference framework that aims to cover all the major areas to be considered. The approach followed was to review the literature regarding blockchain and to identify the main security areas to be addressed. It then proposes a decision-making model and tests the model against a fictitious but relevant real-world example. It concludes with learnings from this research. The reader can be the judge, but the model aims to be a practical valuable resource to be used by any security professional, to navigate the security aspects logically and understandably when being involved in a blockchain deployment. In contrast to the Satoshi quote, this research tries to convince the reader and assist him/her in understanding the security choices related to every blockchain deployment. , Thesis (MSc) -- Faculty of Science, Computer Science, 2021
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  • Date Issued: 2021-10

A sustainability practices educational intervention in response to environmental matters of concern amongst Makhanda youth

  • Authors: Musiyiwa, Fungayi Lona
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/188364 , vital:44747
  • Description: This study responded to urbanisation as one of the challenges affecting youths’ lifestyles in this century. Children and youth around the world are living in overpopulated, polluted and unsafe environments which fail to produce opportunities for learning, play and recreation (World Health Organisation [WHO], 2017). This study explored these issues in the context of Makhanda with an intervention to engage youth in sustainability practices, to help them to strengthen sustainable lifestyles. The participants in this research were members of two eco-clubs from two schools in Makhanda ranging in age from 12-14 years (primary school) and 15-17 years (high school). The study explored how learning processes within a club intervention contributed to the well- being of participating youth and their capacity to live sustainable and fulfilling lives. The research explored (with participants) eight themes as matters of concern namely, ‘education’, ‘home-life’, ‘energy use’, ‘mobility’, ‘leisure and communication’, ‘waste’, ‘water’ and ‘food’. Detailed case narratives exploring Wals’ social learning stages were used to explore the themes. These themes were explored through photo narratives of the youths’ lives and matters of concern in sustainability issues, risks and practices emanating from the Makhanda context. The pedagogical framework for the intervention was guided by Wals’ social learning framework for mobilizing sustainability practices. Social learning interaction took place through all the stages of the framework and the challenges and potentials of the educational intervention were explored in relation to each stage. From the six themes suggested above the youth chose food and water as themes to take forward as a response project. The project pursued was a vegetable garden in which the youth were actively engaged in order to seek and try out sustainable ways of living. An interpretive approach was used within the interpretive paradigm. Qualitative data were generated through focus group discussions, observations, individual interviews and document analysis. Practice architectures theory was used analytically to explore the dynamics of the emergent sustainability practices initiated by the eco-club youth. I used it as a change method and a tool for initiating social learning actions for ‘sustainability practices’ projects. The study indicated that the youth’s key challenges affecting sustainability of their lifestyles are: lack of access to basic infrastructure, recreational facilities, electricity supply, transport, security and water. In this study, it was clear that much of the youth’s involvement in these matters of concern and sustainability issues was at the level of participating in the six themes through Wals’ social learning processes. This allowed youths to develop their knowledge and skills on how to participate in the gardening project rather than simply focusing on the environmental matters of concern in question. The Handprint Resource Books have been designed for educators who are looking for practical ideas to work with in the learning areas of the National Curriculum. The focus is on sustainability practices that can be taken up within the perspective that each learning area brings to environment and sustainability concerns. The use of the Handprint Resource Books promoted active youth participation and interaction encouraging youth to be reflective thinkers, which led to understanding of the issues and the sustainability practices that emerged during the discussions. The Handprint Resource Books focused on sustainability practices within the learning area of environment and sustainability concerns. Due to her facilitation skills, an environmental expert’s presentation on a sustainability topic enabled youths to select the intended project. The involvement of youth in the implementation of the vegetable garden as a sustainability practice empowered youth to be more confident in engaging in a collective action for change as they developed the capability to share and start their own vegetable gardens at their homes. , Thesis (MEd) -- Faculty of Education, Environmental Learning Research Centre, 2021
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  • Date Issued: 2021-10

An interpretive analysis of the experiences of adults working as university support staff

  • Authors: Zini, Thembela Nomonde
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/10962/188888 , vital:44795
  • Description: Work means different things to different people and the different meanings they make of their work has the unique ability of contributing to a sense of identity. Support staff have to negotiate their personal identities and social identities to develop a work identity in the complex South African context that has its unique challenges. Exploring how support staff make sense of their experiences, when it comes to their identities, reveals what identity work strategies they use. An interpretative phenomenological method of inquiry was employed as an initial research method to explore the aspects that impact on the identity formation of support staff at Rhodes University. The study aims to investigate how support staff have constructed a work identity through their constructions of their experiences. Six participants were recruited through a purposive sampling method and data were collected using semi-structured interviews. The study revealed that support staff use the following identity work strategies to negotiate their identities: Financial, Personality, Career mobility, Roles, Status and Esteem, Subjective wellbeing. These themes were derived from the narratives of the participants, using the emphases in the data and suggest that support staff use identity work strategies both outside and within the workplace, when constructing their work identities. The study illustrates that as people ascribe different meanings to work, they will define and negotiate their identities in the workplace based upon those meanings. Identity work is indeed challenging for support staff because they need to use identity strategies that are enhancing to their self-esteem. Identity work is a challenging task because of the many tensions and demands of modern society, as adults negotiate their needs to provide for families and to find ways to construct their job status in positive ways. , Thesis (MA) -- Faculty of Humanities, Psychology, 2021
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  • Date Issued: 2021-10

Evaluation of Megabruchidius tonkineus (Coleoptera: Chrysomelidae: Bruchinae), a candidate biological control agent for Gleditsia triacanthos L. (Fabaceae) in South Africa

  • Authors: Salgado Astudillo, Sara Elizabeth
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/188386 , vital:44749
  • Description: Gleditsia triacanthos L. (Fabaceae) (honey locust) is a fast-growing, deciduous tree indigenous to the United States of America. Introduced around the world as an ornamental tree, it has become invasive in a number of countries. Where it is invasive, G. triacanthos competes and replaces indigenous species; it creates dense stands along watercourses, posing a significant environmental threat. In South Africa, G. triacanthos is regarded as one of the country’s fastest spreading weeds. Gleditsia triacanthos produces numerous seeds contained in large hanging pods. Once dislodged from the pods, the seeds are dispersed by birds and mammals, including livestock, which eat the pods. It has been suggested that the seeds should be the target for biological control programme. Some invasive alien plant species are characterised by their ability to spread and establish in new ecosystems because they tolerate a wide range of environmental conditions. In order to predict areas of likely invasion, species distribution models (SDMs) are used to identify areas climatically suitable for their invasion, so enabling better targeted control of the plant species. Gleditsia triacanthos adapts to a wide range of climates and soil types, and tolerates salinity, drought and frost. Currently primarily restricted to the Grassland Biome of South Africa, G. triacanthos has doubled its distribution area in the past 15 years, and it is not known how far the species will spread. In this study we used two different modelling programmes, CLIMEX and MaxEnt, to predict areas where G. triacanthos could find favourable growing conditions; both SDMs showed that most of the country is suitable for G. triacanthos and that it will probably continue to spread, if left unmanaged, into new bioregions, such as the Karoo. In South Africa, the Asian seed-feeding bruchid, Megabruchidius tonkineus (Pic, 1914) (Coleoptera: Chrysomelidae: Bruchinae) has been recorded in the plant’s seed pods and has been considered as a biological control agent. The insect was not released as part of a formal biological control programme and neither host-specificity nor impact studies were conducted on the species prior to its discovery. In 2017 a decision was made to re-consider its status as a Abstract biological control agent until further details of its biology, host specificity, and impact on the seeds of G. triacanthos in South Africa were available. This study shows that Megabruchidius tonkineus has established across the entire G. triacanthos population in South Africa damaging approximately 9% of seeds. Laboratory studies show that, Megabruchidius tonkineus completes its larval development in the seeds of G. triacanthos in about 66.80 ± 0.6880 SE days before eclosing. In addition, the adult females oviposit on the following Fabaceae species: Arachis hypogaea, Albizia, julibrissin, Cicer arietinum, Pisum sativum, Dipogon lignosus, Peltophorum africanum, Podalyria buxifolia Senegalia burkei, Umtiza listerina and Vachellia sieberiana. However, larval development was limited to G. triacanthos. It is concluded that the seed-feeding beetle is not a threat to native Fabaceae species in South Africa, however, it does not damage enough G. triacanthos seeds to be considered a valuable biological control agent at this stage, and additional seed-feeding biological control agents should be considered to reduce the number of G. triacanthos seeds entering the environment. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2021
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  • Date Issued: 2021-10

Nurturing an identity of land custodianship of young people through a biodiversity learning programme: The Moletele Youth Learning Programme

  • Authors: Mponwana, William Oupa
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/10962/188820 , vital:44789
  • Description: This study was an exploration of value creation through scaffolding in a context specific learning programme with young people within the Moletele Communal Property Association (CPA) who own land through the land reform programme in South Africa. The study aimed to support the development the identity of land custodianship amongst young people by developing their skills and competencies in a situated learning context. The study also informed ongoing support work through the RESILIM-O resilience building project implemented by the Association for Water and Rural Development (AWARD) to help the Moletele Community Property Association to better understand the implications of biodiversity and land use for developing sustainable beneficiation projects and planning. A case study approach was adopted through a learning programme with young people as an in-depth exploration of the complexities of land and biodiversity. Data were collected during sessions in the learning programme where we used a spiral framework to facilitate learning focusing on four themes for primary data: knowledge competence, technical skills, self-organization and collective agency which are linked to building an identity of custodianship. Semi structured interviews were conducted at the end of the learning programme as a secondary data source. The study found that scaffolding remained an important process throughout the learning programme, and different types of scaffolding was needed to support the learning processes and themes. Furthermore, different types of value were created over time through the interactions and activities of the learning programme. The study also found that young people have a desire to participate in their communal property association. Lastly the study revealed that building custodianship as an identity is a continuous, long term process that needs commitment of time, resources and supportive learning processes, for an identity of custodianship to emerge. , Thesis (MEd) -- Faculty of Education, Education, 2021
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  • Date Issued: 2021-10

Potential of the Gravel Filter Towers, Pilot-scale Filter system and Biochar/Clay adsorbents for Bio-Physicochemical remediation and Desalination of greywater

  • Authors: Bani, Siphumze
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/188375 , vital:44748
  • Description: Thesis embargoed until 2023 , Thesis (MSc) -- Faculty of Science, Rhodes University Biotechnology Innovation Centre, 2021
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  • Date Issued: 2021-10

Potential Synergism between Entomopathogenic Fungi and Entomopathogenic Nematodes for the control of false codling moth (Thaumatotibia leucotreta)

  • Authors: Prinsloo, Samantha Lee
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/10962/188832 , vital:44790
  • Description: False codling moth, Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) (FCM), is a major phytosanitary pest of citrus in South Africa. Sufficient control measures for the soil-dwelling life stages of FCM have yet to be identified and owing to restrictions on the use of insecticides, non-chemical control options have been investigated including the use of entomopathogenic fungi (EPF) and entomopathogenic nematodes (EPN). Laboratory and field trials on an indigenous EPF, Metarhizium anisopliae FCM Ar 23 B3, have shown that this isolate is capable of inducing mortality in FCM soil-dwelling life stages. Other agents that have been highlighted as potential controls for soil-dwelling FCM life stages are the EPN species Steinernema yirgalemense 157-C, S. jeffreyense J194 and H. noenieputensis 158-C. This study conducted laboratory bioassays to assess the virulence of these four control agents on fifth instar FCM, in 24-well plates. These results reaffirmed the virulence of the four microbial control agents at their recommended doses of 50 IJs (EPN) and 1×107 conidia/ml (EPF) against fifth instar FCM with 80 to 96% larval mortality recorded. The EPF isolate exhibited the lowest mortality whilst S. yirgalemense induced the greatest mortality. In addition, the lethal concentration (LC) values for each isolate were determined using dose response bioassays. These values were previously unknown for all EPN species and for the EPF isolate based on the methodology used in this study. The LC50 results in order from lowest to highest EPN IJ concentration requirements were 4.38 IJs (S. yirgalemense), 4.47 IJs (S. jeffreyense) and 7.11 IJs (H. noenieputensis). The EPF isolate exhibited an LC50 of 3.42×105 conidia/ml. Lastly, research has shown that the combination of two control agents may increase control of late instar lepidopteran and coleopteran larvae, through synergistic interactions. Thus, the interactions that occurred between the combination of these EPN species with the EPF isolate were determined. This study found that when all three EPN species were combined simultaneously and sequentially with the EPF isolate M. anisopliae FCM AR 23 B3, additive interactions took place with exception of the simultaneous application of S. yirgalemense and H. noenieputensis, with the EPF and S. jeffreyense applied 24 h post EPF application. For the former, a synergistic interaction was found, whilst for the latter two, an antagonistic interaction. Although no strongly synergistic interactions were observed, additive interactions have been shown to reach a synergistic level when certain parameters are changed. Moving forward, a uniform methodology for conducting EPF/EPN interaction experiments has been suggested. It has also been recommended that due to the additive interactions observed in this study, laboratory soil-bioassays and field trials should be carried out for all three EPN species in combination with the EPF isolate. This research will inevitably facilitate the constant knowledge into management strategies for the phytosanitary pest, FCM in South African citrus. , Thesis (MSc) -- Science, Zoology and Entomology, 2021
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  • Date Issued: 2021-10

Practicing conciliation: Towards a practical application of the Equal Weight View

  • Authors: Hartley, Danyel Jordan
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/188341 , vital:44745
  • Description: The Equal Weight View is a frequently discussed position in the philosophy of disagreement. It holds that when someone disagrees with an epistemic peer, they should adjust their belief to be closer to their peer’s belief. While the reasons for adopting this response to disagreement have been debated, there has been less discussion about its utility as a tool for handling real-world disagreements. In this thesis I pursue a version of the Equal Weight View which is useful in practice. I argue that traditional applications of the Equal Weight View do not reflect its underlying principles when they are used to resolve real-world disagreements. I develop an idealized application of the Equal Weight View that addresses the problems traditional applications face in real-world scenarios. Unfortunately, addressing these problems results in an application that is unrealistically cognitively demanding. The application trades being insensitive to the environment it would be used in for being insensitive to the limits of its user. I suggest that we might be able to save the idealized application and work around those limits by either externalizing or simplifying the most demanding aspects of the application. Externalization is best achieved by making use of some kind of computer assistance. Simplification involves replacing taxing data tracking and computation with heuristic methods. While neither approach is ideal, I argue that both get us closer to resolving disagreements in accordance with the underlying principles of the Equal Weight View than traditional applications do. , Thesis (MA) -- Faculty of Humanities, Philosophy, 2021
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  • Date Issued: 2021-10

Quantifying the ecological and socioeconomic implications of a recovery/collapse of South Africa’s West Coast rock lobster fishery

  • Authors: Eggers, Jessica Marguerite
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/10962/188854 , vital:44792
  • Description: The West Coast rock lobster (WCRL) Jasus lalandii fishery is South Africa’s third most valuable fishery, but the stock is currently at less than 2% of its pristine biomass. Scientists are warning that if no measures are taken, the WCRL could face commercial extinction. The necessary reductions in the global Total allowable Catch (TAC) seen in past years have had large economic implications for the WCRL value chain, but research into the socio-economic aspects of this fishery is limited. This study, therefore, aims to establish an overview of the economic revenue over the seasons 2016/17 – 2018/19 by exploring changes and trends in the net seasonal income (NSI) for the fishery, sectors within the fishery and different stakeholders. It also investigates the prospects for the sectors and different actors in this fishery over the seasons 2019/2020 - 2030/31 through analysis of the net present value (NPV) under three proposed global TAC management scenarios (global TAC of 640 tonnes, 1084 tonnes and 1280 tonnes). Data concerning costs and incomes as well as dynamics, mechanisms and concerns surrounding the fishery were collected from stakeholders in the different sectors through interviews and surveys. Further, official records from DEFF (catches, actors, vessels and quotas) and projections made by the Marine Resource Assessment (MARAM) team at the University of Cape Town (rates of recovery of the resource and future catches under the different TAC scenarios) were obtained and analysed. Cost and income data were summarised and models characterising the economic flows within the fishery were created. Calculations regarding the NSI and NPV were made using Monte Carlo simulations to account for the uncertainty surrounding many of the input variables. Results show that while the fishery as a whole made economic profits for the three seasons, the decreasing quotas in 2018/19 had a disproportionately negative impact on some of the representative individuals examined within the different sectors. The projections indicate that while each of the sectors as a whole would continue to make profits largely proportional to their allocation under the different TAC scenarios, many vessel owners in the fishery are likely to face economic losses or very marginal gains under the lower quota options, while the NPV for quota holders who outsource the catching of their quota are likely to be proportionally less affected by the changes in global TAC. This dynamic is important to consider for the future of this fishery. If the resource is to recover, and fishing activity is to continue equitably under the decreased quotas that the recovery of the biomass necessitates, the socio-economic context and the dynamics within which the fishers operate must be considered and studied more extensively and socio-economic consequences of a lower global TAC mitigated while improving the ecological status of the resource. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2021
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  • Date Issued: 2021-10

Queer as Africa: Representations of queer lives in selected Nigerian, Kenyan, and South African literature and film

  • Authors: Wilson, Jon Stephen Edward
  • Date: 2021-10
  • Subjects: Africans in literature , Africans in motion pictures , Homosexuality in literature , Homosexuality in motion pictures , Sexual minorities in literature , Sexual minorities in motion pictures , African literature -- History and criticism , Motion pictures, African -- History and criticism , Sexual minorities -- South Africa -- Public opinion , Sexual minorities -- Kenya -- Public opinion , Sexual minorities -- Nigeria -- Public opinion , Sexual minorities -- South Africa -- Social conditions , Sexual minorities -- Kenya -- Social conditions , Sexual minorities -- Nigeria -- Social conditions
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/187428 , vital:44651
  • Description: This thesis contests the notion that nonnormative sexualities are ‘un-African’ by examining a range of representations of queer African lives on film and in literature, produced by Africans for Africans, as a means to interrogate the role played by the interconnected histories of colonialism, religion, and the policing of queer intimacy, specifically in Kenya, Nigeria, and South Africa. Through a close reading of a selection of texts from these three countries, this thesis takes a cultural-historical approach to exploring the complex struggles engaged in by queer people in Africa to protections under the law, and to represent themselves in literary and cinematic narratives. The first chapter is focused on the Kenyan film Rafiki (2018), directed by Wanuri Kahiu, which tells the story of queer love between two young Kenyan women who face the vehement condemnation of their relationship from their homophobic community. The film was banned in Kenya, but the director was granted a temporary injunction by Kenya’s high court in order for it to be screened in Nairobi. This made Rafiki the first queer film ever to be screened in Kenya, and viable for an Academy Award nomination. The second chapter focuses on the bold assertion of a queer African identity through the short story collections Queer Africa: New and Collected Fiction (2013) and Queer Africa 2: New Stories (2017). Written by various authors from the African continent, and compiled and edited by Karen Martin and Makhosazana Xaba, both collections offer a wide variety of fictional narratives focused on queer experiences in Africa. The second chapter has a focus on stories from Kenyan and Nigerian authors and explores notions of home, queer belonging, and visibility. The third chapter presents a close reading of the South African film Inxeba (2017), also known as The Wound, directed by John Trengove and adapted by Trengove and Thando Mgqolozana from Mgqolozana’s novel, A Man Who Is Not A Man (2009). The film depicts the traditional Xhosa initiation ritual, ulwaluko, and is set in the rural Eastern Cape. Inxeba is an important case study in the history of queer representation in Africa, as the film hit a nerve with many, interrogating what South Africans believe about culture, traditions, masculinity, and the right of artists to represent sacred ritual in art. This thesis pays attention to the historical entanglements between homophobia, imperialism, and Christianity – relationships that continue to affect the experiences of queer people in Africa and attitudes towards them and interrogates why queer individuals are still being left out of efforts towards creating a new normal in postcolonial Africa. This thesis suggests that increased visibility is a key aspect of queer activism in Africa – through the act of representation, sharing lived experiences, and telling queer stories. , Thesis (MA) -- Faculty of Humanities, Literary Studies in English, 2021
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  • Date Issued: 2021-10

The construction of phthalocyanine- carbon nanoparticle conjugates for applications in photodynamic therapy and non-linear optics

  • Authors: Matshitse, Refilwe
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/188397 , vital:44750 , 10.21504/10962/188397
  • Description: The syntheses and characterization of symmetric and asymmetric Pcs functionalized at the peripheral position and sometimes positively charged are reported. The Pcs had either H2, zinc or silicon as central metals and have pyridyloxy, benzothiozole phenoxy, and respective cationic analogues as ring substituents. The Pcs were linked to carbon based nanoparticles such as graphene quantum dots, carbon dots, and detonation nanodiamonds (DNDs) via an ester, amide bond and/or π - π stacking. The physicochemical characteristics of the Pcs were assessed when alone and when in a conjugated system. Both symmetrically and asymmetrically substituted benzothiozole Pcs when quaternised displayed higher triplet and singlet oxygen quantum yields than their unquaternised counterparts. Linkage to carbon nanoparticles (especially to detonation nanodiamonds) had an increasing effect on triplet and singlet oxygen quantum yield. However, a general decrease in singlet oxygen quantum yield on linkage to doped detonation nanodiamonds was associated with the screening effect of DNDs. Heteroatom doped DNDs-Pc nanohybrids have less singlet oxygen than Pcs alone due to molecular structural stability associated with strain that is relatively reduced upon linking Pcs. The In vitro dark cytotoxicity and photodynamic therapy of selected Pc complexes and conjugates against MCF-7 cells was tested. All studied Pc complexes and conjugates showed minimum dark toxicity making them applicable for PDT. When Pc complexes are alone, there is less phototoxicity with >22% cell viability at concentrations ≤ 50 μg/mL relative to conjugates with <22% cell viability at concentrations ≤ 50 μg/mL. There was no direct relationship between PDT and singlet oxygen quantum yields. Nonlinear optical characteristics of complexes was improved upon conjugation of DNDs. Absorbance, input energy, percentage loading, central metal, substituent of Pc and nature of interaction (covalent, noncovalent) are amongst some of the factors that influence nonlinear absorption properties of materials used in this study. All materials followed reverse saturable absorption through two photon absorption mechanism at the excitation wavelength of 532 nm. Aggregates reduce excited state lifetime and Beff under high concentrations/absorbance. A direct relationship between absorbance and Beff of DNDs nanoconjugated systems at low concentrations result in increased optical limiting characteristics of materials. The findings from this work show the importance of linking (nonlinear optics and photodynamic therapy) and doping (photodynamic therapy) photosensitisers such as phthalocyanines and sometimes boron dipyrromethenes onto carbon based nanoparticles for the enhanced characteristics in variable applications. , Thesis (PhD) -- Faculty of Science, Chemistry, 2021
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  • Date Issued: 2021-10

The Effects of Monaural Beat Technology on Learners' Experiences of Music Performance Anxiety (MPA)

  • Authors: Flanagan, Jayson Edward
  • Date: 2021-10
  • Subjects: Performance anxiety Alternative treatment , School music South Africa Makhanda , Music students South Africa Makhanda Examinations , Beats (Acoustics) Psychological aspects , Monaural Beat Technology
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/10962/188419 , vital:44752
  • Description: Music performance anxiety (MPA) is related to the experience of persisting, distressful, apprehensions about and/or actual impairment of performance skills in a public context, to a degree unwarranted given the individual’s musical aptitude, training and level of preparation (Salmon 1990). This research project set out to investigate learners’ subjective experiences of the effects of monaural beat (MB) vibrational frequencies on their experiences of MPA. The research project was a qualitative study based on a phenomenological research paradigm, which fundamentally aims to explore an experience in its own terms (Smith et al. 2009). The research participants consisted of four subject music pupils at St Andrew’s College and The Diocesan School for Girls and were interviewed through in-depth, semi-structured interviews over two practical examinations. The results suggested that various factors contribute to the experience of music performance anxiety, such as the performers’ perceptions of audience reactions, as well as the context of the performance. Self-esteem and the performer’s fragile sense of self-worth and self-confidence also play an important role in influencing their music performance anxiety. However, listening to monaural beats during a performance has the ability to lower levels of music performance anxiety by eliciting the following effects: an improved sense of confidence within the listeners; a sense of calm; the monaural beats working on a passive awareness level that allows the beat to operate at a sub-conscious level; the ability to focus better on the task at hand as well as benefit the listener in non-musical contexts such as studying; general concentration or ordinary tasks such as gardening or going for a run. The research suggests that listening to monaural beats during a musical performance can benefit the performer by lowering levels of MPA. As a result, the performer will experience an improved sense of confidence, calmness and the ability to focus better on the task at hand. Monaural beats have also shown to be a useful method of dealing with MPA instead of resorting to pharmaceutical drugs or other methods of coping such as playing games for distraction. , Thesis (MMus) -- Faculty of Humanities, Music and Musicology, 2021
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  • Date Issued: 2021-10

The factors to be considered by the competition authorities when a fine may cause the firm to exit

  • Authors: Quilliam, Layne Edwin
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/10962/188408 , vital:44751
  • Description: The Competition Act empowers the Competition Tribunal to levy fines against a firm for certain contraventions of the Act. Such fines are statutorily capped to prevent the fine from causing the firm’s exit. This maximum is based on the overarching principle of fairness which precludes a fine, on its own, from destroying a firm’s business. However, the Competition Appeal Court acknowledged in 2013 that fines below this cap may still cause a firm to exit. The purpose of this paper is to propose the factors that should be considered when determining a firm’s ability to pay such a below-cap fine. These factors are the calculation of the fine, probable exit, causation of exit and the competitive effect of the firm’s exit. The fining provisions of the Act are initially explored to provide context for the discussion and are then compared to equivalent provisions in Europe. Liquidation and business rescue proceedings are then described as the most common forms of a firm’s exit from the market. Methods for determining the causal relationship between the fine and the firm’s exit are explored through delictual law’s factual and legal causation. The competitive effects of the firm’s exit are premised on the purpose of the Competition Act and are evaluated through the Competition Act’s merger provisions, specifically, the failing firm factor. These proposed factors are then tested through hypothetical facts to analyse their possible interactions and efficacy. , Thesis (LLM) -- Faculty of Law, Law, 2021
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  • Date Issued: 2021-10

The synthesis and characterisation of Sn(IV) porphyrin derivatives and their potential application in anti-cancer and antimicrobial photodynamic therapy

  • Authors: Dingiswayo, Somila
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/10962/188843 , vital:44791
  • Description: In photodynamic therapy (PDT), the activation of light-sensitive drugs in tumour cells produces reactive singlet oxygen species, which cause tumour destruction through a cascade of biochemical reactions. Over the years, the wavelength of activation has been shown to be a critical factor in the penetration of light. Hence the properties of photosensitiser dyes in this context shape their ability to treat deep-seated tumours. In this study, the synthesis, structural characterisation and photophysicochemical properties of a series of Sn(IV) porphyrins with meso-methylthiophenyl rings that have been prepared to study their PDT and photodynamic antimicrobial chemotherapy (PACT) activity properties are reported. The series of Sn(IV) complexes is comprised of a porphyrin (1-Sn), a corrole (2-Sn), a chlorin (3-Sn) and an N-confused porphyrin (4-Sn). Herein, the low symmetry Sn(IV) porphyrin derivatives are shown to have excellent singlet oxygen generation capabilities, and lifetimes of the triplet excited states were in the microsecond range. For example, 4-Sn had a singlet oxygen quantum yield (ФΔ) and an excited triplet state lifetime (τT) of 0.88 and 27 μs, respectively. The complexes were studied using UV-visible and magnetic circular dichroism (MCD) spectroscopies. Interestingly, the positive-to-negative sign sequences of the Faraday B0 terms of 2-Sn and 3-Sn reveal that the structural modifications involved break the degeneracy of the MOs derived from the 1eg* LUMO of the porphyrin 1-Sn. In contrast, a conventional negative-to-positive sign sequence is observed for 4-Sn, since the confusion of a pyrrole moiety also results in a large separation of the 1a1u and 1a2u MOs of the porphyrin 1-Sn that are derived from the HOMO of a C16H162−parent hydrocarbon perimeter. The trends in the electronic structures of the Sn(IV) complexes were further investigated through a series of time-dependent density functional theory calculations, so that the suitability of the different types of complex for use in singlet oxygen applications could be further explored. During in vitro photodynamic antimicrobial chemotherapy (PACT) studies, chlorin derivative 3-Sn had the highest activity towards S. aureus and E. coli with log10 reductions of 10.5 and 8.74, respectively. The unusually high activity of 3-Sn against E.coli suggests that the interaction of neutral photosensitisers with gram-negativebacteria is more complex than previously understood. Anti-cancer PDT studies demonstrated that the photosensitisers had negligible dark cytotoxicity. Upon photoirradiation, the Sn(IV) complexes consistently exhibited IC50 values lower than 15 μM against MCF-7 adenocarcinoma cells. An IC50 value of 1.4 μM for 4-Sn after activation at the deep-red region of the spectrum demonstrates that complexes of this type merit further in-depth investigation. The results provide evidence that the low-symmetry Sn(IV) chlorins and N-confused porphyrins merit further in-depth study for use in singlet oxygen applications. , Thesis (MSc) -- Faculty of Science, Chemistry, 2021
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  • Date Issued: 2021-10

The use of African languages in traditional courts: a Luyengweni case study

  • Authors: Nyakambi, Ntombizethu
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/10962/188810 , vital:44788
  • Description: Forensic linguistics is a relatively new field in South Africa. This field which forms part of the applied linguistic discipline seeks to look at the application of linguistic knowledge, methods and insights to the forensic context of the law. This is a forensic linguistic study that seeks to look at the use of African languages in the traditional courts. The researcher explored the traditional courts of Luyengweni, a rural area situated in KwaBhaca at Mount Frere in the Eastern Cape. The concept of African languages usage is explored within the boundaries of customary laws as outlined in Section 6 of the South African Constitution of 1996. To fully elicit the use of African languages in the traditional courts of Luyengweni this study employed an exploratory qualitative research design method. This research method allows for data to be collected from the participants using semi-structured interviews, observation and other qualitative methods of data instrumentation. Relevant community members of Luyengweni such as Chiefs and their councillors, ordinary members of the community and the court secretary were interviewed by the researcher and the data was translated, transcribed and analysed. The thesis made use of a thematic analysis. These themes showed that the use of African languages in traditional courts is still relevant, however, the imbalances of language use in both common and customary law need to be addressed. The study revealed that the traditional courts still serve as law institutions that people trust to bring about justice, therefore language use as one of the pivotal tools in the justice system needs to be considered for effective justice to be carried out. , Thesis (MA) -- Faculty of Humanities, African Languages, 2021
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  • Date Issued: 2021-10

To fail at becoming South African: Moral blindness, liminality, and Rainbowism

  • Authors: Moletsane, Dimpho
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/188352 , vital:44746
  • Description: This thesis, broadly speaking, concerns personal & national moral transformation and being-becoming. It draws generally from multiple disciplines that I have gained insights from throughout my undergraduate experience, including discourse theories in journalism, postcolonial theories in literature, and nationalism in political theory, among others. In particular, it follows done work by the Rhodes University Allan Gray Centre for Leadership Ethics (AGCLE) and aims to take a place among research conducted as part of a broader project entitled ‘Understanding and Overcoming Moral Blindness: the impact of IiNtetho zoBomi—Conversations about Life’ (hereafter ‘ZoBomi’). The goal of ZoBomi is to foster ethical agency among its participants. This work involves developing an awareness of the psychosocial realities of our lives that can work to interrupt our ability to function in ways that we would most truly want to upon reflection, as well as the stake we have in controlling the impact of these realities on our lives. And thus questions such as ‘How do we want to live?’, ‘What kinds of people do we want to be?’; ‘What gets in our way of being the kinds of people we most truly want to be upon reflection?’ are engaged and addressed throughout the course. The aim of ZoBomi is not to merely tell participants (from a position of authority orexpertise1) that they are such ethical agents who care about who they are and how they live and act in the world; about the importance of coming to a better understanding of the human predicament, of themselves, one another, and their social reality. Instead, ZoBomi aims to show to its participants the extent to which “organising and taking responsibility for our lives is something that we want to do once we have given the matter considered attention, even though doing so may be (and typically is) emotionally taxing”. , Thesis (MA) -- Faculty of Humanities, Philosophy, 2021
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  • Date Issued: 2021-10

Towards Reconfiguring the Agricultural Expert System (AES) for Black Small to Medium Farmer Development for Commercialization: A progressively focused policy literature review and social learning dialogue in the Eastern Cape Raymond Mhlaba Local Municipality

  • Authors: Maqwelane, Lwanda
  • Date: 2021-10
  • Subjects: Uncatalogued
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/10962/188876 , vital:44794
  • Description: This study focuses on the agricultural expert system (AES), its inherited and potential reframing capabilities for the development, growth and transition of black small to medium farmers (BSMF) into the commercial sector. The study was conducted as a critical analytical policy review of implemented policies pre-and post 1994 that subsequently highlighted the thematic continuities and discontinuities of policy reform and the subsequent impact on BSMFs using the AES as a conceptual lens. The study aimed working with stakeholders in the AES in the Raymond Mhlaba Local Municipality as a case study to critically engage and question the AES and its contemporary framing and potential reframing and continued impact on the BSMFs development. This was conducted through a dialogical social learning process in partnership with diverse voices that cut across the contemporary agrarian landscape that included “universities, think tanks, vocational training providers, standards-setting agencies, trade associations that provide specialized training, education, information, research and technical support” (Porter, 2000, p.17). The data for the social learning dialogue process was generated through an iterative analysis of dialogical social learning workshops, focus groups and semi-structured interviews. The analysis focused on the framing (Chapters 2, 3, and 5) and reframing of the AES (Chapter 6). Through dynamic engagement within the knowledge hub (contextual social learning and literature), the study surfaces a potential alternative discourse that actively includes the BSMFs as a crucial component of the commercial sector AES as the analysis shows these are largely excluded. This alternative discourse occurred through dialogical interactions with all participants via a pro-actively constituted social learning process, enriched and deepened by literature as indicated above. Main recommendations of the study are: 1. The AES must be framed to address the holistic value chain of BSMFs to help address underlying policy dualism, 2. Public Private Partnerships are needed to support BSMFs development and these should adopt a social learning approach that is reflective of complex realities 3. There is need for better understanding of roles and contributions of stakeholders in the AES to avoid duplications. , Thesis (MEd) -- Faculty of Education, Education, 2021
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  • Date Issued: 2021-10

Uncoupling the exploitation and climate change effects on the biology of Cape monkfish, Lophius vomerinus Valenciennes 1837 in Namibia

  • Authors: Erasmus, Victoria Ndinelago
  • Date: 2021-10
  • Subjects: Lophius -- Namibia , Lophius -- Climatic factors -- Namibia , Lophius -- Effect of human beings on -- Namibia , Lophius -- Food -- Namibia , Lophius -- Reproduction -- Namibia , Lophius -- Age -- Namibia , Lophius -- Growth -- Namibia , Lophius -- Habitat -- Namibia , Lophius -- Conservation -- Namibia , Fisheries -- Namibia , Overfishing -- Namibia , Fishery management -- Namibia , Lophius vomerinus (Valenciennes, 1837) , Cape monkfish
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/188329 , vital:44744 , 10.21504/10962/188329
  • Description: Cape monkfish, Lophius vomerinus Valenciennes 1837, has supported the Namibian fishing industry for decades, historically as by-catch and recently as a target species. This species is also an important predator in this region. With increasing levels of exploitation and unprecedented climate change, an understanding of the changes in the long-term biological parameters of this species is critical. To date, there has been a scarcity of spatio-temporal studies that have examined and compared the biological aspects of Cape monkfish in relation to climate change and exploitation pressure. Investigations into changes in feeding habits, reproduction strategy, age and growth can provide valuable information for the sustainable management and conservation of this species. This thesis aimed to improve our understanding of the impacts of exploitation and climate variability on the biological parameters of Cape monkfish in the Namibian marine waters, thereby contributing to efforts directed at sustainable harvest and management of this resource. This was achieved through temporal and spatial comparisons of feeding, reproductive scope, age and growth, and catch statistics. The study used data collected during the monkfish swept-area biomass surveys of 2001–2005 and for 2007–2018, hake (deep-water hake Merluccius paradoxus Franca 1960 and shallow-water hake M. capensis Castelnau 1861) swept-area biomass surveys of 2017 and 2019, port sampling programme data collected from April 2014 to December 2019, and monkfish commercial fishing activities collected between April 2001 and December 2019. Based on historical feeding data (1986 – 1987) and contemporary feeding data (2015-2018), Cape monkfish feeds on a variety of prey species from seven groups: Teleost, Cephalopoda, Crustacea, Echinoidea, Elasmobranchii, Gastropod and Porifera. The diet was characterised by a high prevalence of empty stomachs (43.9%), showing low feeding intensity, but most prevalent in juveniles (52.9%). Although the diet composition varied at different life stages, Teleosts (especially deep-water hake Merluccius paradoxus Franca 1960) were the main constituents of the diet for all size classes as per the Index of Relative Importance (%IRI). The results highlight the particular importance of the deep-water hake M. paradoxus (by %IRI) in the diet of Cape monkfish across all size classes. There is a clear dominance of hake in both studies, which means that any overexploitation or climate-driven population decline in hake will most likely have an impact on Cape monkfish. Feeding composition was dependent on the season (p < 0.05), with the type and quantity of prey ingested changing seasonally, showing the ability of Cape monkfish to adjust its diet, depending on possible environmental parameters which consequently influence prey availability. In general, the spatial and temporal variability of the main prey items suggests that the species is highly opportunistic with a broad trophic adaptability. Comparison of historical and contemporary stomach content data indicates that Cape monkfish appear to have changed their diet, probably reflecting the availability of forage species over time and space, possibly due to climate change, fishing pressure, or both. The broad trophic adaptability for Cape monkfish highlights their adaptive potential to increasing anthropogenic stressors such as climate change. However, the dominance of the commercially important deep-water hake, M. paradoxus, in the diet during contemporary times highlights that complex trophic interactions may play a role in altering the northern Benguela fisheries. The general male to female sex ratio was measured at 1:1.67, with significant variation across depth, size class, and year (p < 0.05). Comparison of length at 50% maturity (L50) for Cape monkfish between historical (2004–2006) and contemporary time (2015–2019) showed no significant differences in both sexes, with no significant changes in the L50 for females (χ2 = 1.53, df = 1, p = 0.2154), and males (χ2 = 0.41, df = 1, p = 0.5204) between the two periods. The monthly gonadosomatic index (GSI) showed that Cape monkfish spawn throughout the year with peaks between July and September for females and August for males, similar to those observed 20 years ago. Spawning hotspot areas were identified and were consistently located between 22⁰ and 25⁰S in deeper water (> 250 m) for the 2001–2018 time series. Comparison of the contemporary (2015–2019) proportions of developing, ripe and spent gonads to the historical study data (1996 – 2000) show minimal differences. Ripe ovaries capable of spawning (Stage IV) were dominant in July (23.8%) and August (26.2%), while ripe testes were prevalent in April (52.5%) and November (28.5%). The discovery of the veil (a gelatinous, flat ribbon structure containing individual eggs) off Namibia for the first time (during this study) is a significant because this result provides important reproduction activities information of this species, which were never recorded off Namibia. The location where the veil was discovered, off Swakopmund (22⁰30'S, 13⁰25'E), provides further evidence of the identified spawning hotspot areas, this location is also identified as a monkfish consecutive hotspot fishing area. The ages, growth rates, and length-weight relationships were compared between fish collected during monkfish commercial fishing activities between 1996 and 1998 (Period 1) and during monkfish routine monitoring surveys from 2014 to 2016 (Period 2). A total of 607 (size range: 9–96 cm total length (TL)) and 852 (size range: 9–96 cm TL) Cape monkfish were aged by reading sectioned illicia, during Periods 1 and 2, respectively. The length-weight relationships were W = 0.012L3.035 (r2 = 0.98) and W = 0.014L 2.989 (r2 = 0.98) for females and males, respectively, during Period 1, and W = 0.01L2.97 (r2 = 0.98) and W = 0.01L 3.03 (r2 = 0.98) for females and males, respectively, in Period 2. The growth of Cape monkfish (in cm) for combined sexes was described by Lt = 94(1 − e(−0.10(t−(-0.31))) in Period 1 and Lt = 98(1 − e(−0.10(t−(-0.33))) in Period 2. Females grew significantly faster during Period 1 (LRT results from Maartens et al., 1999), while male and female growth was not significantly different during Period 2 (F = 0.65, p = 0.58). There were no significant differences between the male and female growth curve in Period 2 (F = 0.65, p = 0.58). Although the growth curves are similar between Period 1 and Period 2, the larger fish are in Period 2 are lighter than those in Period 1. This finding is important to the monkfish fishing industry because fish is sold by weight. This finding may suggest that although the fish grow similarly by length, changes in the environmental conditions may have resulted in a reduced condition of the fish. In terms of mean age, the historical Period 1 had a slightly lower mean age of 4.40 compared with a mean age of 5.49 during Period 2. Slight differences were also observed in the age structure between the two periods, with 2-year-olds (20.3%) the most abundant age class in the historical period while 5-year-old fish (18.3%) were most abundant in Period 2. Although the spatial distribution of the catch was not available for Period 1, 0-year-old fish were distributed from 22⁰ to 24⁰S, and 25⁰ to 26⁰S in shallower waters of 166–290 m during Period 2. Only fish between 5 and 16 years old were found off the documented historical nursery area off 28º S. The similar growth curves and spatial overlap of nursery habitats between Period 1 and Period 2 suggest that Cape monkfish may be fairly resilient to the rapid environmental change reported in this region and to the extensive levels of exploitation for the species. However, the recent spatial shifts in the nursery areas are sensitive to disturbance and may indicate that these changes could be having an impact on the early life stages of the species. Continued monitoring may be necessary to understand the consequences of these spatial shifts for the age and growth and resilience of the species. Analysis of the overall spatial and temporal catches of monkfish (both Cape monkfish and shortspine African monkfish) off Namibia between 1998 and 2018 identified noticeable spatio-temporal trends. The pattern of fishing activities for Cape monkfish is heterogeneous, with identified ‘hotspots’ in specific areas. Of particular importance is the consecutive hotspot, between 1998 to 2018 for monkfish fishing activities between 25⁰ and 26⁰ S. The kernel density analysis indicated that the area around 24⁰S, and between 26º and 27 ⁰S, between Walvis Bay and Lüderitz, had the highest total catch densities (~300 kg/km2), suggesting that this is the core of the stock abundance. Annual monkfish catches have fluctuated since the inception of the fishery in 1994, with a drastic decline in the catch recorded after 2003 through to 2018. Generally, there has been an underutilisation of the total allowable catch (TAC) for most of the years. The decrease in catches and the underutilisation of the TAC might be indicative of the reduction in the stock abundance. However, external factors such as lack of capacity of the fishing industry and the administration can contribute to underutilisation of TAC. Basic regression analysis between total monthly catches and monthly sea surface temperature (SST) yielded low r-squared values indicate that in all three grids, only ~ 1% of the variation is explained between SST and total monkfish catches in these areas. The most prominent points to consider from this study are the results of the comparative feeding study (Chapter 3), reproductive indicators (Chapter 4) and age and growth (Chapter 5). Certainly, there have been changes in feeding, demography, and distribution of the species in the last two decades – climate-driven changes were recorded in the feeding habits of Cape monkfish, spatially and temporally – but despite the changes in prey species composition, distribution and abundance in various habits and periods, Cape monkfish was able to switch prey species, reflecting wide trophic adaptability. The dominance of M. paradoxus at all size classes in all analysed habitats is a significant result because. The peak spawning period has remained the same between July and September, as previously reported in Period 1. The consecutive spawning hotspots were identified in the areas between 22º and 25ºS. From a fisheries management perspective, the spawning ground and spawning season should be protected (by means of closure). The evidence of changes in length at 50% maturity presented in this study hints at both climate change and extensive exploitation pressure. The discovery of the veil for the first time in this study is very important; however, it might be sampling related and not driven by climate or exploitation pressure. Finally, the change in the Cape monkfish distribution discussed in Chapter 6 may be attributed to a shift in the distribution or fishing effort as a consequence of shallow water depletion. , Thesis (PhD) -- Faculty of Science, Ichthyology and Fisheries Science, 2021
  • Full Text:
  • Date Issued: 2021-10
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