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    Demersal fish distribution in the shallow marine nearshore and estuarine seascape of Algoa Bay: Nursery areas and the effect of environmental drivers

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    Estuaries and shallow marine nearshore areas are highly productive and valuable ecosystems, which provide numerous habitats for fish and support fundamental ecological links with other environments. Assessing fish distribution across estuarine and marine nearshore habitats is important to identify ecologically important habitats and develop effective management strategies for coastal fishes, many of which are important fishery species. Despite this, only a few studies have focussed on fish community patterns across an estuary and marine nearshore gradient concurrently, particularly including early life history stages, to determine the nursery value of both environments, and to examine whether these two coastal environments have distinct fish assemblages in relation to physical factors. The main aim of this study was to assess the environmental drivers of demersal fish communities in soft-bottom benthic habitats in two permanently open estuaries and adjacent marine nearshore areas (5 – 10 m) of Algoa Bay, South Africa, as well as to assess the relative roles of these two habitats as settlement and nursery areas for demersal fish species. A 1.5 m, conical shoeless beam trawl net was used to sample the demersal fish community concurrently in each habitat between July 2017 and September 2019. Sampling was conducted in July 2017, February, March, May, July, August, October and November 2019 and February, April and September 2019. DNA barcoding was used to verify identification of the early life history stages of fish caught in the estuarine and marine nearshore areas of Algoa Bay. In addition, since the two estuaries (Swartkops and Sundays) are heavily polluted, the effect of low dissolved oxygen and hypoxia and associated shifts in spatial distribution of demersal species was investigated. The two sampled estuaries had a higher abundance of demersal fishes, with a total of 6437 fishes (28 species) caught (3752 and 2685 individuals with 24 and 20 species recorded in the Sundays and Swartkops estuaries, respectively). Species richness was higher in the marine nearshore of Algoa Bay, with 29 species (797 individuals) caught. Of the 7234 individuals caught, the identification of 100 specimens, in either a larval or early juvenile phase, were uncertain and therefore DNA barcoding was used to verify their identification. Of these 100 individuals, 86 were positively identified to species level using COI sequences. Fourteen failed to amplify by PCR and could only be identified morphologically. The marine nearshore sites were dominated by species which spawn in the marine environment and are not dependent on estuaries (marine species and marine estuary-opportunists), whilst the estuaries were dominated by estuarine spawners or marine spawners dependent on estuaries to some degree. Two discrete demersal fish assemblages were identified representing the marine nearshore and the estuary, with no significant differences observed between the two estuaries (Sundays and Swartkops). The differences observed between the marine nearshore and estuary were mostly driven by salinity, turbidity, silt and organic content of the sediment. These distinct fish assemblages might be considered as indicators for the respective environments they inhabit. Both habitats were dominated by early life history stages (larvae to juveniles), indicating the nursery function of both habitats. Early life stages collectively comprised 97% of the catch in the marine nearshore and 68% in the estuary. Young-of-the-year (YOY) juveniles ( 20 μg Chl-a l-1) that result in instances of bottom water oxygen depletion (< 4 mg/l). During the present study in the Sundays Estuary, low oxygen waters were recorded in the middle reaches (Site S5) mostly during summer (four months of low DO conditions). In the Swartkops Estuary, low dissolved oxygen was recorded in the upper reaches during spring. The lowest dissolved oxygen concentration recorded was 0.5 mg/l and 2.4 mg/l in the bottom waters of the Sundays and Swartkops estuaries, respectively. Selected dominant species were only absent from areas where dissolved oxygen was < 1 mg/l and present in the adjacent sites (for example Site S4, and S3) where DO was higher mostly during January 2019. As such, the low dissolved oxygen concentrations recorded in the Swartkops Estuary did not have a noticeable impact on fish distribution, although the total abundance of species did show a slight decline when dissolved oxygen was < 3 mg/l. This study demonstrates the importance of concurrently examining estuarine and nearshore marine habitats in order to identify ecologically important habitats, which has important implications for the development of effective management strategies for coastal fish populations, particularly in the light of anthropogenic change. In addition, in order to identify nursery hotspots it is crucial to correctly identify all the species occupying these areas. As such, this study confirms the importance of also using DNA barcoding for fish identification, particularly for the early life history stages of cryptic species (e.g. Argyrosomus inodorus and Argyrosomus japonicus).Thesis (PhD) -- Faculty of Science, Ichthyology & Fisheries Sciences, 202

    Pair of knitted green and black slippers with pom poms

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    A pair of knitted green and black slippers which were a special gift received in 1988 when Dr Bam returned home from Switzerland. These slippers were made by women in the women prison in Limpopo in South Africa and given to Dr Bam when as a special gift. Dr Bam was smuggled into prison. The smuggling was on Sundays.Photo of original objectDonated/gifted to Nelson Mandela University Archives by Dr Brigalia BamForms part of: Brigalia Bam collectio

    Golden yellow circular doily

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    Golden yellow circular crochet doily, created by Ms Bam Senior.Donated/gifted to Nelson Mandela University Archives by Dr Brigilia BamForms part of: Brigalia Bam collectio

    Integrating blockchain and microgrid technology to enable peer-to-peer energy trading: a business process model

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    Traditional centralised energy systems are coming under increasing pressure because of decarbonisation, decentralisation, and digitisation. A lack of energy security and the inability to manage bi-directional electricity flows constitute two of the biggest challenges faced by centralised systems. Furthermore, in South Africa, the country’s energy system remains monopolised with one large utility satisfying most of the country’s electricity demand. This study is motivated by the need to address energy security within such a monopolised market. To redress the problems highlighted above, this study explores how blockchain and microgrid technology can be integrated to enable decentralised energy production and trading in South Africa. As such, this study develops a fully integrated blockchain-based microgrid energy trading system model. The functional requirements of the system are presented in the form of a business process model. Amongst other benefits, an active blockchain-based microgrid energy trading system provides a means to bolster energy security for the systems’ users. A unique aspect of this study’s approach to energy trading is the utilisation of blockchain’s native tokenizing capabilities. Prosumer energy tokens are minted to create a digital currency for local peer-to-peer energy exchange. A commons-rule based approach is adopted for governing energy resources. As such, this study demonstrates that commons-based solutions provide a feasible alternative to market and profit driven trading for organizing local energy exchange. The primary deliverable of this study satisfies the request of various blockchain researchers for blockchain research to focus on holistic conceptualisations, rather than on the minutiae of blockchain technicalities. Eight core functional requirements of a blockchain energy trading system were identified prior to the construction of the process model. The functional requirements were elicited during a scoping review as a part of the secondary data collection process. Expert review was utilised to verify the functional requirements of the blockchain energy trading system. Once the experts were identified, each expert completed a questionnaire with the intention to verify the requirements. The above process constituted the expert review process for the study. Additionally, the syntactic correctness of the business process model was verified by a business process modelling expert. Weber’s Theory of Evaluation constitutes the theoretical underpinning for the evaluation of the system parts. This study contributes the first publicly accessible business process models of a blockchain-based microgrid energy trading system. This study seeks to advance the discussion of a more integrative and cross disciplinary approach concerning blockchain research, particularly as it pertains to microgrid energy trading.Thesis (MCom) -- Faculty of Commerce, Department of Information Systems, 202

    The challenges and opportunities in ESG integration in investment activities for private equity firms/funds in South Africa

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    Responsible Investing (RI) is an investment strategy that considers not only the economic but also the environmental, social and governance (ESG) issues in the investment analysis and post-investment activities. The consideration of ESG issues is aimed at generating long-term risk-adjusted financial returns and a positive social and environmental impact. This research seeks to contribute to the study of responsible investment (RI), as it relates to private equity investments, an area not well researched. This research also seeks to contribute to the academic literature on responsible institutional investment in South Africa; the opportunities it presents to optimise portfolios, as well as the means with which the challenges faced in integrating ESG factors in investment activities may be overcome. More specifically, the challenges and opportunities for the integration of ESG factors in the investment process were investigated through the experiences of a small sample of South African private equity firms. The sample of private equity firms that participated in this research are signatories of the United Nations Principles of Responsible Investing (UNPRI). Representatives of the participating firms were interviewed in line with the qualitative research design and the post-positivist paradigm of this research. The research design and paradigm are chosen to explore the experiences of practitioners in their integration of ESG issues in the investment process. This research shows that the challenges to ESG integration for the private equity firms considered have remained largely consistent over the last ten years. The challenges include industry skills and knowledge gap and the lack of reliable and comparable ESG data at the portfolio company level. The Opportunities presented, by adopting responsible investing as an investment strategy, are rooted in protecting the downside (risk management) and in finding new value creation opportunities. In summary, it was found that the participating firms continue to face significant capacity challenges in overcoming the challenges to mainstreaming ESG in investment processes. Further research may explore whether the challenges and opportunities that persist from the findings of this research are pervasive throughout the entire sector and whether innovative ways have been found to overcome the challenges have been found by private equity firms that are not signatories of the UNPRI.Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 202

    The effectiveness of networking and collaboration in creative hubs: a case of Hub@Goethe

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    This research took the form of a case study investigating the effectiveness of a single hub in South Africa, namely Hub@Goethe in Johannesburg. The context of the creative economy and creative industries provided insight into the experiences of creative cultural labourers in the new economic model. The context emphasised the research problem which considered the difficulties experienced by creative and cultural entrepreneurs and their career paths who, through labour precarity, remain isolated from the market, without access to physical spaces, network connections and business knowledge to realise their business ideas. The literature reviewed revealed how co-working office spaces, creative spaces and hubs provide creative entrepreneurs with the spatial infrastructure, amenities, and network access to mitigate challenges in the creative cultural sectors. These spaces offer a multitude of different amenities which is specific to their community’s needs. Guided by the theory of social capital and structural holes reviewed in the literature, the effectiveness was assessed by the hub’s ability to provide network access benefits or resource endowments. The research looked at whether the hub could provide creative cultural entrepreneurs with resource benefits such as a) access to social interactions, collaboration, and knowledge sharing, b) access to business or professional skills-based education programmes and mentorship, c) access to market and d) generation both social and economic benefit. The research adopted a qualitative approach, seeking insights into the creative entrepreneurs’ experiences at the hub utilising one-to-one interviews. The thematic analysis confirmed that the hub was effective overall in providing entrepreneurs with access to benefits or resource endowments embedded in the network, confirming that hubs may be an effective tool in mitigating difficulties experienced by creative entrepreneurs in the creative industries. The research also showed areas of improvement where the hub could increase its experienced effectiveness, especially in reference to routes to market. The research findings inferred the importance of physical space, proximity and accessibility has on collaborative practices amongst creative entrepreneurs within the hub space.Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 202

    Magnitude

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    My thesis is a collection of lyric, narrative, and prose poetry directed towards two forms of death – physical death and the disavowal of the self. Many poems focus on the death of my mother, and the work required after loss to sort through a family’s life in my Harare childhood home. This associative exploration draws together childhood memories, encounters with physical objects, letters, and songs, as well as with the city and its people. Tadeusz Rózewicz’s Mother Departs has influenced my approach to writing of my mother’s death, particularly how to grant her a voice in the telling. I also draw on the poetry of Harmony Holiday and Pascal Petite, in their attention to the complexities and emotional dangers of the mother-daughter bond. Other poems draw on the work of Adrienne Rich, Audre Lorde, Judy Grahn, Ocean Vuong, and Saeed Jones, in terms of imagining queer life into poetry, the use of the erotic as a means of empowerment, and developing a queer political identity, to examine various aspects of queer love, including the heartaches associated with self-denial.Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 202

    Design, synthesis, characterization and evaluation of Chitosan-based hydrogel for controlled drug delivery system

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    Hepatitis B infection is a deadly infectious disease caused by the hepatitis B virus and is responsible for many deaths every year worldwide. Despite medication and vaccines against hepatitis B infection, it still presents high morbidity and mortality among populations. This is partly due to factors such as a long medication period of the existing treatments, resulting in poor patient compliance and leading to treatment failure. In addition, this situation can be responsible for the observed emerging drug resistance. Hence, novel drugs and drug delivery systems are needed to tackle this matter. Many strategies have been used to develop long-acting drug delivery systems treatment for several infectious diseases. Hydrogel drug delivery systems have shown interesting results as controlled drug delivery systems for several drugs. Therefore, the present study aimed to develop chitosan grafted poly (acrylamide-co-acrylic acid) hydrogel and apply it as a pH-sensitive controlled delivery system of tenofovir disoproxil fumarate (TDF). TDF is a nucleoside reverse transcriptase inhibitor used as first-line treatment of hepatitis B chronic infection and in the treatment of other viral infections. The free-radical polymerization method was utilized to modify chitosan by grafting acrylamide and acrylic acid and using N, N’-methylene bisacrylamide as the crosslinking agent to prepare the hydrogel, followed by an optimization of parameters that could affect the swelling capacity. The prepared chitosan-g-poly(acrylamide-co-acrylic acid) hydrogel was characterized using Fourier Transmission Infra-red spectroscopy (FTIR), X-Ray Diffraction (XRD), Thermal Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Energy-dispersive X-ray spectroscopy (EDS), Scanning Electron Microscopy (SEM), and was evaluated for cytotoxicity using a HeLa cell assay. TDF was used as a drug model, it was loaded by the swelling equilibrium method, following by the investigation of the release profile of TDF-loaded hydrogel at pH 1.2 and 7.4. A successful synthesis of chitosan grafted poly(acrylamide-co-acrylic acid) hydrogel was confirmed by Fourier Transmission Infra-red spectroscopy (FTIR), X-Ray Diffraction Spectroscopy (XRD), Thermal Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Energy-dispersive X-ray spectroscopy (EDS) and Scanning Electron Microscopy (SEM). Optimization results showed that the ratio of monomers impacted the swelling ratio of the hydrogel and both the concentration of the crosslinking agent, and the reaction initiator also affected the swelling ratio. The synthesized hydrogels were sensitive to pH and ionic strength. Hydrogel swelling was lower in acidic solutions and higher in neutral and basic solutions and decreased with the increasing ionic strength. Furthermore, SEM results revealed that hydrogel have a rough and fibrous surface structure with numerous pores. Cytotoxicity studies demonstrated that the hydrogel was non-cytotoxic at 50 μg/ml against HeLa cells which suggested a good biocompatibility of the material. TDF was loaded and released from the hydrogels and showed an encapsulation efficiency and drug loading percentage ranging from 81-96% and 8-10%, respectively. TDF release profile was found to be low in buffer solution of pH 1.2 (in the range of 5-10%) and much higher (38-53%) at pH 7.4 within 96 hours. TDF maintained its chemical integrity after release and the hydrogels can therefore be proposed as a new controlled-release drug delivery system for hepatitis B treatment.Thesis (MSc) -- Faculty of Science, Chemistry, 202

    Perceptions of Role Players in the Pharmaceutical Manufacturing Sector in South Africa Regarding the Proposal of a National Health Insurance System

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    The proposed implementation of National Health Insurance (NHI) is attracting considerable interest among healthcare workers, as observed in the large quantity of available literary evidence. The available research is mainly focused on the perceptions of healthcare workers, working under the proposed NHI reform. Based on a literature gap observed in recently published articles on perceptions of healthcare professionals regarding the implementation of NHI, the researcher aimed to assess the opinions of key stakeholders in the pharmaceutical manufacturing sector in South Africa. This study employed a qualitative approach, using semi-structured interviews with key stakeholders employed in the pharmaceutical manufacturing sector. Their perceptions regarding the NHI were analysed and interpreted through thematic analysis in order to determine whether they have a positive or a negative perception towards the introduction of the NHI reform in South Africa. The majority of role players are in full support of NHI and there was a consensus amongst the participants that there will be great opportunities for the pharmaceutical manufacturing sector. Regarding the capabilities relating to capacity to supply, participants felt that South Africa’s pharmaceutical manufacturing sector has sufficient infrastructure to support the roll out of the NHI. Furthermore, participants felt positive about increased accessibility to pharmaceutical care by all South Africans, regardless of race, social and economic status.Thesis (MA) -- Faculty of Health Sciences, 202

    Towards a sustainable food management system: Exploring indigenous food practices of sorghum grain in the Moshana village, Northwest, South Africa

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    This research study explores indigenous sorghum food management practices as a pathway towards sustainable food systems. The level of hunger is ever-increasing, and so is the global population. Regions less industrialized and developed suffer the most as they host growing populations and most of the worlds undernourished. Further intensified in this problem are a culling and unforgiving food systems run by a few conglomerates and a knowledge system driven by a histography of ‘othering’ even in its knowledge creation process. Although there exist institutions such as the United Nations Food and Agricultural programs, these remain relegated to policy and intergovernmental level, in the process, not being mindful of the real food issues faced at the grassroots level. This research study centralizes indigenous food practices to make sense of how rural and indigenous livelihoods such as those located in the Moshana village thrive and survive in a monopolized and urban-centred food climate like South Africa. By interviewing 12 participants, living, and taking part in the Moshana village food systems and employing stringent face-to-face semi-structured interviews, we present an indigenous food system as experienced and shared by Moshana Village Community members. The findings present an array of indigenous and food management practices, perspectives through an African ecological philosophical view. Conceptually inspired by the works of Vandana Shiva and many global south thinkers on seeds, grains and sustainable indigenous food systems, this study hopes to reinsert back the centrality of food in the growing field of African Sociology. The findings clearly show that elderly women are preserving the Sorghum knowledge and preservation processes. These practices have assisted the Moshana Village community members to cope with food shortages and lockdown restrictions during the strict COVID-19 lockdown in South Africa. The study concludes with clear need for the archiving and intergenerational communication of food management within the rural communities.Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 202

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