PhD / Doctoral

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Open Access
3D cine DENSE MRI: ventricular segmentation and myocardial stratin analysis
(2013) Auger, Daniel A; Spottiswoode, Bruce S
Includes abstract. Includes bibliographical references.
Open Access
The 52 and 60 kD Ro/SS-A : antigens where are they? : do anti-Ro/SS-A autoantibodies cause cutaneous disease?
(1998) Yell, Jennifer Anne
Systemic lupus erythematosus, considered a multifactorial autoimmune disease, is a disease affecting many systems, with associated immunological abnormalities. It has a striking diversity of clinical patterns, pathologies and prognoses. Genetic factors determine the inherited baseline, on which environmental, hormonal and infectious triggers act to produce autoantibodies. Ro antibodies have been considered pathogenic in subacute cutaneous and neonatal lupus erythematosus. I affinity-purified antibodies to the 52 kD Ro from immunised rabbits (whole 52 kD protein) and human sera (using two immunodominant regions of the protein). I affinity-purified antibodies to the 60 kD Ro from immunised rabbits (whole 60 kD protein) and human sera (using two immunodominant regions of the protein, as well as the total "native" protein). Using these purified antibodies, with immunofluorescence on normal neonatal human keratinocytes, I showed that the 52 kD Ro is mainly cytoplasmic and the 60 kD Ro is mostly nuclear, with some fine cytoplasmic staining. I looked at the capacity of these purified antibodies to penetrate living keratinocytes under various conditions (hormones, drugs and vitamins). No antibody penetration was found, although one whole serum gave low levels of intracellular fluorescence. I studied the putative membrane translocation of 52 kD and 60 kD Ro under conditions of stress (UV A or UVB with or without hormones, drugs, vitamins and heat shock). I could not identify translocation of the 52 or 60 kD antigens with purified antibodies, although some whole sera showed fluorescence. I can find no evidence that antibodies directed against the 52 and 60 kD Ro antigens cause cutaneous disease.
Open Access
6-deoxy-6-amino chitosan: A plant defence priming biopolymer that enhances resistance against Botrytis cinerea in tomato and Fusarium verticillioides in maize
(2024) Moola, Naadirah; Rafudeen, Mohamed; Jardine Mogamat
Aminochitosan, derived from chitosan, features enhanced water solubility, and improved antifungal efficacy attributed to an additional amine group at the C-6 position, hinting at its superior antifungal potential compared to native chitosan. This PhD thesis aimed to explore the optimal concentration of aminochitosan and its molecular weight fractions for enhanced antifungal and priming properties in the tomato/Botrytis cinerea and maize/ Fusarium verticillioides pathosystems. In the B. cinerea pathosystem, various concentrations of aminochitosan were assessed for their antifungal effectiveness against B. cinerea growth and sporulation. Additionally, in planta studies were conducted to phenotype and quantify temporal stress responses using both qualitative and quantitative chlorophyll fluorescence imaging as well as DAB assays combined with microscopy. Despite batch-to-batch variations, aminochitosan consistently inhibited fungal growth and sporulation in a dose-dependent manner. In planta, aminochitosan pre-treatment induced robust defence responses in tomato leaves, resulting in a resistant phenotype that was mediated through a combination of enhanced photosynthetic efficiency as evidenced by enhanced Fv/Fm and chlorophyll content. The DAB assays suggested that these resistant phenotypes were also ROS-independent (H2O2 specifically) due to the strong positive impact of direct inhibition. The resistant phenotype and optimal efficacy of the aminochitosan MW fractions was observed at 3.5-15 kDa for antifungal efficacy and 15-20 kDa for in planta efficacy. Consequently, leaf senescence, hypersensitive responses and therefore necrosis were mitigated suggesting that aminochitosan primed defence responses in both mock and B. cinerea inoculated leaves. A temporal, label-free quantitative proteomic analysis revealed the differential priming of key molecular mechanisms underpinning aminochitosan primed states both with and without B. cinerea infection at 6 and 9 hpi in the tomato/B. cinerea pathosystem. Aminochitosan treatment (1 mg/mL) differentially regulated proteins as early as 6 hpi with some of the induced responses being sustained up to 9 hpi. Additionally, several proteins were oppositely regulated between aminochitosan pre-treatment and B. cinerea infection, indicating differential regulation patterns between the “primed state” and the “triggered state”. The proteomic data therefore partially validated the ‘priming' capacity of aminochitosan in 5- week-old tomato leaves, specifically diamino 3 when used as a foliar spray at a concentration of 1 mg/mL. The bimodal effects of aminochitosan in a maize/Fusarium verticillioides pathosystem were investigated by assessing the direct antifungal efficacy and elicitation of plant defence properties in planta. Aminochitosan displayed significant antifungal activity on both radial growth and sporulation at a minimum concentration of 1 mg/mL. Aminochitosan was also assessed in planta as preventative or curative treatments in maize seedlings infected with F. verticillioides at two time points. In the preventative treatment, salicylic acid accumulated during the early stages of infection (biotrophic phase) whereas in the curative treatment, jasmonic acid accumulated during the necrotrophic phase. In summary, we demonstrated that water-soluble aminochitosan possesses key properties that enable plant priming in addition to its superior direct antifungal activity compared to native chitosan. We also identified the optimal molecular weights and concentrations necessary for achieving maximum and 50% inhibition activity
Open Access
A biochemical study of some of the hydrolases to be found in the latex of the pawpaw, Carica papaya L
(1968) Skelton, Gerald S; Kench, J E
Using fresh papaya latex as the starting material, this thesis describes methods for the isolation and purification of three major proteinases by column adsorption chromatography; a comparative study of certain salient chemical and physical properties of these enzymes is presented. Reference is made to some conflicting results in the literature concerning papain studies, and an effort has been made in this work, by further experimentation, to account for some of the discrepancies. A supplementary study of biochemical interest has been the collecting of latex from the same growing fruit at fixed time intervals : analysis of the samples shows the changes in the yields of latex and enzyme content during the six months that the fruit takes to ripen.
Open Access
A biophysical, biochemical and serological study of selected members of the enteroviruses
(1969) Smith, Martin Sidney
The purpose of this investigation was to study the biophysical and biochemical properties of some of the enteroviruses. Previous work in this laboratory on several members o.f this large sub-group of the Picornaviruses had emphasised the importance of a more detailed examination of some of the surface properties of representative strains of enteroviruses, by currently available techniques.
Open Access
A biscuit fortified with iron, iodine and B-carotene as a strategy to address micronutrient deficiencies in primary school children
(2001) Van Stuijvenberg, Martha Elizabeth; Hussey, G. D.; Benade, A. J. S
Deficiencies of vitamin A, iron, and iodine continue to be prevalent in developing countries worldwide and can, in addition to the classic consequences such as nutritional anaemia, goitre, cretinism, xerophthalmia and blindness caused by severe deficiencies, also affect the growth, development and immunity of young children. The various internationally acknowledged strategies for combating micronutrient deficiencies include high-dose supplementation, food fortification, dietary diversification and nutrition education. The aim of this research was to evaluate a micronutrient-fortified biscuit as a strategy to address micronutrient deficiencies in primary school children from a poor rural community. The research comprised three phases. During the first phase the effect of a biscuit fortified with iron, iodine, and B-carotene on the vitamin A, iron and iodine status of 115 children was evaluated and compared with 113 controls, in a randomised placebo-controlled trial. To enhance the absorption of iron a vitamin C-fortified cold drink was given together with the biscuit. Anthropometric status, cognitive function and morbidity were assessed as secondary outcomes. The 12-month intervention resulted in a significant improvement in serum retinol, serum ferritin, transferrin saturation, haemoglobin and urinary iodine excretion. Morbidity and cognitive function, particularly the cognitive function in the children presenting with low iron status and with goitre! at baseline, were also favourably affected. Linear growth was positively affected only in the children with marginal iron stores at baseline. During the second phase of this study the long-term effectiveness of the biscuit programme, in terms of elimination of micronutrient deficiencies, compliance, acceptability and sustainability, was evaluated in a longitudinal study over a period of 30 months. In addition, cross-sectional data on vitamin A and iron status from subsequent studies conducted in the same school at 33, 42 and 45 months after the start of the original biscuit intervention, during which time the fortified biscuit continued to be distributed at the school, are reported. Although micronutrient status improved significantly during the 12 months of the first study, all variables (except urinary iodine) returned to pre-intervention levels when the schools reopened after the summer holiday. Serum retinol increased again during the next nine months, but was significantly lower in a subsequent survey, carried out directly after the summer holiday; this pattern was repeated in two further cross-sectional surveys. Iron status showed no recovery during a subsequent intervention period when the vitamin C-fortified cold drink was supplied on a less frequent basis, or during the period that ferrous bisglycinate was used as iron fortificant. Because of the compulsory iodisation of salt, that came into effect halfway through the first phase of the study, improved iodine status, as measured by urinary iodine excretion, was maintained. In the third phase of the research, red palm oil, a rich natural source of B-carotene, was examined as an alternative vitamin A fortificant in the biscuit. This study contained elements of both a randomised placebo-controlled trial and an equivalence trial. The biscuit with a red palm oil-based shortening was shown to be as effective as the biscuit with fl-carotene from a synthetic source in improving the vitamin A status of these children. In conclusion, the results of the studies described in this thesis showed that a micronutient-fortified biscuit is a feasible, practical and effective way of improving the micronutrient status of primary school children from a poor rural community. Long-term evaluation of this programme, however, showed that improved micronutrient status is not sustained during the long summer school holidays, and it is suggested that the biscuit programme is supplemented with other strategies, such as local food production programmes and nutrition education. Red palm oil, with all of its additional qualities (i.e. no trans fatty acids; rich source of antioxidants), appears to be an attractive alternative for use as a vitamin A fortificant. The choice of the iron compound to be used in the biscuit, however, needs further investigation.
Open Access
A case study exploring an occupational perspective of social inclusion among young adults dually afflicted with substance use disorder and HIV/AIDS in Zimbabwe
(2021) Nhunzvi, Clement; Galvaan, Roshan; Langhaug, Lisa; Harding, Richard
Background: Curtailing adverse social determinants of health is pivotal to achieving the 2030 Agenda for Sustainable Development`s vision for a healthy and inclusive society. In Zimbabwe, fulfilling Vision 2030 may involve adopting socially inclusive approaches, particularly for young people dually afflicted with HIV and substance use disorders. However, social inclusion remains conceptually unclear and underutilized in relation to marginalized groups in low resource settings. This study sought to explore and understand how dually afflicted young adults with substance use disorders and HIV in Zimbabwe experienced and negotiated their social inclusion. Methods: This study utilised a qualitative instrumental case study design. Primary qualitative and quantitative data were collected to develop a thorough understanding of the case of an occupational perspective of social inclusion among dually afflicted young adults in Zimbabwe. The multiple methods used in this study included: i) narrative inquiry with five dually afflicted young adults; ii) in-depth interviews with five key informants; iii) document analysis of seven policies; and, iv) exploratory cross-sectional survey of social inclusion and associated factors (n=105). These multiple methods and sources contributed to the study`s trustworthiness. Multi-level case study analysis was applied as follows; 1st level: narrative analysis of each of the five young adults` stories, descriptive analysis of key informant interviews, document analysis and descriptive statistical analysis of the cross-sectional survey data. 2nd level: thematic case analysis drawing from all four data sources. 3rd level: theorised conceptual occupational constructs. Findings: Five narratives illustrated how using agency and having occupational choices were central to the young adults` experience and negotiation of social inclusion. The overarching Case theme was “Navigating an already troubled life: Striving for belonging and well-being”. This consists of three categories: 1) Dealing with a context of mixed realities, 2) Trying to adjust to new challenges and, 3) Life on the margins. These findings show how dually afflicted young adults in Zimbabwe respond and resist the influences of dominant discourses through dynamic and interconnected actions that shape their realities. Conclusion: The study describes and explains how dually afflicted young adults experienced and negotiated their social inclusion. The data affirms the role of agency and proposes a more critical view of occupational choice, activist occupational choice, in understanding social inclusion. As an emergent concept it is categorized by occupational choices, largely defying standard norms of engagement, and aims to break away from oppressive systems and problematic situations. Recognising the diverse manifestation of agency yields an appreciation for how occupations that are indigenous, collective, and resist oppression contributes to experiences of social inclusion.
Open Access
A case study exploring disability inclusion within the Muslim Ummah in South Africa
(2023) Mayat, Nafisa Essop; Amosun, Seyi Ladele; Galvaan Roshan
Religion and spirituality are central to the way many people, including persons with disabilities, make sense of both the world itself, and their place in that world. However, in most scholarship focusing on disability, religion, as a way of understanding and dealing with disability, is side-lined or absent (Imhoff, 2017). Islam has a long rich history in South Africa and is currently one of the major religions here (Mahida, 2012). Followers of Islam are commonly referred to as members of the Muslim Ummah as a collective, an Ummah that includes persons with disabilities and non-disabled persons. Given the paucity of research focusing on disability in the Muslim Ummah in South Africa, this study sets out to gain insight into the way disability inclusion is enacted within the Muslim Ummah in South Africa. The research question asks: How is disability inclusion interpreted, experienced and enacted by people within the Muslim Ummah in South Africa? Adopting an interpretative qualitative research approach and applying an intrinsic case study method, the research was conducted with members of the Ummah in three major cities in South Africa, viz. Durban, Johannesburg and Cape Town. Data was generated from persons with disabilities, family members of persons with disabilities, the Ulema and a non-disabled person from the Ummah from each city. In-depth face-to-face interviews and a review of three Muslim publications were used as data gathering mechanisms. Interviews were held with seven persons with disabilities, either a physical or sensory disability, five family members of participants with disabilities, six Ulema and three non-disabled persons. All participants were aged 18 and older. Data was analysed by looking for themes that emerged from the data. Three themes, “Seen as Inferior'', “Carrying the Weight for Inclusion” and “We Are Not Doing Enough”, each with two sub-themes, emerged from the analysis. “Seen as Inferior'' and its two sub- themes, ‘' Gaze of Othering and ‘'The Deep Impact of Disability'', highlight the way in which persons with disabilities are viewed as inferior within the Ummah and how this is reflected in the gaze of non-disabled persons on persons with disabilities and their families, and the impact of this gaze. ‘'Carrying the Weight For Inclusion” emphasises the responsibility that persons with disabilities have assumed in order to be accepted into and included in the Ummah and this is demonstrated through the two sub-themes, “The Unspoken Responsibility of Negotiating Persons with Disabilities” and ‘'Negotiating the Effort to be at the Masjid”. “We Are Not Doing Enough” explains that although some aspects of inclusion are evident within the Muslim Ummah, the pace of change is very slow and inclusion remains inadequate. Sub-themes ‘'Inclusion could Create Ease and Belonging” and “Still a Journey to Travel to be Included” capture the way disability inclusion is interpreted and experienced by the participants of the study, highlighting that much work is still needed to attain full inclusion and to create ease and belonging for persons with disabilities within the Ummah. The discussion explains how the dominant discourse around disability is one that reflects an ableist, normative, colonial narrative. This narrative influences how disability inclusion is enacted within the Ummah, belabouring a move to full inclusion. The phenomenon of an unconscious exclusion of persons with disabilities within the Ummah is discussed as it emerges from this dominant discourse, together with the silence that sustains the continuation of the exclusion. The ways in which this unconscious exclusion plays out in many spaces and places significant to the lives of persons with disabilities are identified. It is proposed that, in order to achieve full inclusion and belonging for persons with disabilities within the Ummah, there needs to be a re-shaping in the thinking around disability through generating new knowledge and by challenging the dominance of the normative, ableist narrative. Informed by a decolonial turn, pathways towards full inclusion and belonging of persons with disabilities within the Ummah are proposed. It is suggested that collective action by both persons with disabilities and non-disabled persons within the Ummah is needed for full inclusion and belonging to transpire. The pathway to full inclusion and belonging would enable systemic change around disability within the Ummah to ensue and it would help move the de-colonisation project forward.
Open Access
A case study of emerging practice in speech-language therapy in a community practice context
(2019) Abrahams, Kristen; Kathard, Harsha; Pillay, Mershen; Harty, Michal
Background: The profession of speech-language therapy (SLT) continues to struggle with challenges around equity and service delivery. The dominant medical model, characterised by one-on-one, individualised health care, is struggling to serve the large population in need of services. As such, there is a need to reconceptualise SLT practices toward a social justice focus. The study used clinical education as the entry point of exploration into how emerging professional practices (EPPs) may be developed. Aims/Objectives: The study aimed to describe and analyse a case study of an emerging professional practice in SLT as part of a university-school partnership in a peri-urban settlement in South Africa. The objectives were: 1. To describe and analyse the practice methods of the EPP, 2. To describe and analyse the educational and knowledge bases which support the EPP, and 3. To describe and analyse the underlying epistemology, ontology and methodology underpinnings shaping the EPP. Method: A qualitative case study methodology, guided by critical theory and decoloniality, was used. Final year SLT students were the primary participants for the study. Data were collected in the form of document analyses, participant observations, interviews, photovoice, and experiential drawings from a number of stakeholders (including SLT students, a school principal, a project coordinator, a library assistant and a clinical educator) from January to December 2017. The data were analysed using reflexive interpretation (Alvesson & Sköldberg, 2009) as a guiding frame. Findings: The three-level analysis process was used to generate the thesis offering. The first level of analysis was the construction of the overall case narrative - documenting the practice methods of the EPP through the experiences of the SLT students. The second level of analysis used thematic analysis approach to identify key themes emerging from the case narrative. Four key themes were explored in the form of narratives, collages and paintings. The third level of analysis used decoloniality (i.e. coloniality of power, knowledge and being) and the Relationship of Labouring Affinities (RoLA) as critical lenses to deepen my understanding of the case. Through using both RoLA and decoloniality, dialogue emerged as a critical form of engagement toward developing EPPs. The study specifically puts forward the concept of critical dialoguing as a necessary process for conscientisation and change. Conclusion: The findings of the study illuminated how SLT students navigated through their experiences of disruption of their traditional practice. The findings weave together participant narratives, drawings and collages to engage the reader in the EPP. The findings showed how critical engagement with political, historical, social and linguistic influences underlying their work in communication, facilitated new learning and insight into SLT practice. The thesis offering discusses the role of critical dialoguing in opening up space for critical discussions about the profession. In conclusion, supported disruption provided students with a platform to interrogate current SLT practices, re-examine the viability of practices to serve populations, and reflect on how the SLT profession can adapt and change with the changing needs of the population.
Open Access
A chronicle of cultural transformation: ethnography of Badagry Ogu musical practices
(2020) Kunnuji, Joseph; Bruinders, Sylvia
This thesis examines the musical practices of Badagry Ogu people from both historical and contemporary perspectives and provides strategies for their further integration into the changing social and economic landscape characteristic of 21st-century Lagos. Badagry emerged as a Nigerian town bordering the Republic of Benin in the 19th-century colonial delineation processes, which neglected ethnic frontiers. Consequently, Badagry Ogu people, being a minority ethnic group and geographically peripheral in Nigeria, have been politically, economically and socially marginalized for generations. Using ethnographic methods in studying selected indigenous musical bands (Gogoke, Gigoyoyo, Kristitin and Akran Ajogan), a biographical sketch of master drummer Hunpe Hunga, and an applied ethnomusicology method of collaborative music composition and arrangement, I chronicle the musical heritage of Badagry Ogu people. In addition, I suggest an approach for its recontextualisation into different creative economies. I engage Thomas Turino's framework for identity and social analysis, including the concepts of cultural cohorts and cultural formations, in exploring the different attitudes, among Badagry Ogu people, towards indigenous music. I advocate for and outline a contemporary approach for musical recontextualisation as a means of inclusivity and economically empowering performers of indigenous Ogu music in Badagry. This thesis includes my additional arrangements to the studio recordings of Gogoke. The recontextualisation process, which commenced with Gogoke's recording of indigenous instruments and vocals in Badagry Lagos Nigeria, reached its full fruition in the overdubs of Western musical instruments in Cape Town, South Africa. To further explore the theme of inclusivity, I examine current gender practices in Ogu communities evident in the gendered musical practices of contemporary Badagry. With its indepth analysis of Ogu genres, musical instruments, gender issues and a framework for recontextualising African indigenous musics, this thesis, while filling the gap in the study of ethnic minorities in Nigeria, is a significant contribution of the nuanced artistic practices of Badagry Ogu people to African music scholarship.
Open Access
A clinico-pathological study of schistosomiasis in South Central Africa.
(1948) Gelfand, Michael
A study of bilharziasis as a whole, based largely on pathological and clinical experience, has not been attempted in Africa outside of Egypt. The most impressive work in Egypt in this connection is that Fairley on the experimental infection of monkeys, which he published in 1920. Elsewhere in Africa, a number of smaller publications dealing with a particular or restricted clinical branch of schistosomiasis has been contributed by various authors, notably from South Africa. Th most important of these is Cawston. Valuable contributions from the Congo were made by such workers as Fisher and Chesterman. From West Africa particular mention must be made of Blacklock, and from Nyasaland of Dye and Gopsill. Interesting clincial papers have also been published on bilharziasis from East Africa.
Open Access
A collection of diverse theoretical, philosophical and sociological writings on various aspects of the sonata principle
(1974) Christopher Ballentine
The diverse works presented in these two volumes bear a sit;nificant relationship· to ca.ch other and to a common underlying theme, whi.ch may be said to be an attempt to enlarge our aYmreness of the nature and the possibilities of the Sonata Principle. All were expressly written for publication; one has already been published.
Open Access
A collective self-governance framework for urban facilities management settings: application at public transport interchanges in economically depressed areas in Cape Town
(2024) Miller, Mxolisi; Michell, Kathleen
Government investment in urban infrastructure and facilities, such as public transport interchanges, benefits local communities. However, the literature suggests that equivalent investments in governance and management of public transport interchanges must accompany the infrastructure investment to avoid physical and functional obsolescence. This study examined the willingness of the users of public transport interchanges, such as minibus taxi operators and informal traders, to participate in the collective self-governance of their public transport interchanges. Furthermore, this study closed the knowledge gap regarding the psychosocial-economic factors motivating minibus taxi operators and informal traders' willingness to participate in public transport interchange collective self-governance institutions. This research is approached from the perspective of integrating the three pillars of facilities management: people, place, and process, with special focus on the last pillar (in the context of collective self-governance). This study merged the Social Identity Model for Collective Action (SIMCA), Place Attachment Theory, and Elinor Ostrom's Design Principles for Self-Governance of Common-Pool Resources to form the theoretical framework. The merging of these three theories produced five critical constructs that were utilised to develop the conceptual framework: place attachment, group-based anger, group identification, group efficacy, and collective selfgovernance. Furthermore, the conceptual framework postulated eight hypothesised relationships for this study. These hypotheses were quantitatively tested using survey questionnaires and convenience sampling methods. The surveys were carried out at four public transport interchanges in economically depressed areas of Cape Town: Dunoon, Mitchell's Plain, Nyanga, and Khayelitsha. The survey targeted the minibus taxi operators and the informal traders at these public transport interchanges. A total of 316 questionnaires were found suitable and included in the study. The survey data was analysed using Partial Least SquaresStructural Equation Modelling (PLS-SEM), Smart PLS Version 3 software. The study findings revealed that all eight hypothesised relationships were statistically significant. As a result, it was determined that each of the theorised relationships were crucial for the functioning of the collective self-governance framework; consequently, they were all retained. In addition, the study found that users' emotional attachment to public transport interchanges leads to their willingness to participate in collective self-governance institutions. However, the framework developed in this study argues that while this relationship exists it is mediated by three psychological and cognitive factors, namely, 1) users identify themselves as part of a collective; 2) users' willingness to preserve, maintain and protect the public transport interchange; and 3) users' beliefs in their collective abilities to resolve public transport interchange challenges. The study findings further show that the collective self-governance framework has significant explanatory and predictive power (R2 and Q2 values, respectively). These findings provide empirical evidence that confirms that the minibus taxi operators and informal traders who responded to this study showed a strong willingness to participate in collective selfgovernance institutions at the public transport interchanges. In addition, the reliability and validity collective self-governance framework was confirmed by testing it at multi-public transport interchanges and with multi-groups of minibus taxi operators and informal traders using PLS-SEM and One-Way ANOVA. Finally, this study makes several original contributions to the urban facilities management literature. Firstly, merging The Social Identity Model for Collective Action (SIMCA), Place Attachment Theory, and Elinor Ostrom's Design Principles for Self-Governance of CommonPool Resources into one framework is a major theoretical contribution. Secondly, the psychosocial-economic factors motivating minibus taxi operators and informal traders' willingness to participate in public transport interchange collective self-governance institutions constitute an original contribution. Thirdly, the development and testing of the eight hypotheses in this study, also represent a unique empirical contribution. Fourthly, this study makes a significant methodological contribution to the urban facilities management literature using PLS-SEM and One-Way ANOVA using multi-site, multi-group study areas. Lastly, this study will likely encourage practitioners and policymakers to consider collective self-governance as one of the governance modes for public transport interchanges. This study suggests that minibus taxi operators and informal traders would consider collective self-governance of their public transport interchanges if policymakers and practitioners presented them with the opportunity to do so.
Open Access
A commentary on book 6 of Achilles Tatius Leucippe and Clitophon
(2022) Bentel, Berenice; Chandler, Clive
Achilles Tatius' novel, Leucippe and Clitophon (2nd c. CE), is a product of the literary experimentation in prose fiction during the Greek intellectual renaissance under the Roman Empire known as the Second Sophistic. For all appearances, the story follows the usual narrative course of the ancient Greek erotic adventure novels: boy meets girl, love occurs at first sight, and Fate attempts to keep them apart, triggering an odyssey of bizarre escapades and daring exploits that reaches its inevitable happy conclusion with their reunion and marriage. Achilles Tatius, however, takes each of these tropes far beyond their usual scope, displaying a ludic (and at times ludicrous) panache for defying the genre. This thesis provides the first extensive literary and philological commentary devoted exclusively to the Sixth Book of the novel. I examine both Achilles' unconventional approach to genre and storytelling, and his play on prevailing theories of psychology, physiology, and philosophy to enrich and enliven his narrative.
Open Access
A common maritime regime for the South China Sea
(1994) Sun, Kuan-Ming; Devine, D J
The South China Sea is a semi-enclosed sea in two respects. In terms of the geographical reality, the region is readily separable from the waters surrounding it. Moreover, it falls under the 1982 Law of the Sea Convention, which requires littoral states to cooperate in the maritime sphere. At present, a number of problems beset the region.
Open Access
A comparative analysis of metaphorical expressions used by rural and urban Ndebele speakers: the contribution of S'ncamtho
(2018) Ndlovu, Sambulo; Hurst, Ellen
This thesis explores language expansion and change through metaphorical expressions that originate with urban youth varieties. It focuses on the impact of S'ncamtho, an Ndebele-based urban youth variety of Bulawayo in Zimbabwe along the variables of rural/urban, sex, age and level of education. The thesis uses Cognitive Metaphor Theory to build on research on metaphor in urban youth varieties to answer the overarching question; how is S'ncamtho impacting Ndebele? It confirms that sex and sexuality, music and partying, love and relationships are popular themes in S'ncamtho. The thesis identifies relexicalisation and replacement of metaphoric vehicles as the main metaphor derivational strategies in S'ncamtho and confirms the existence of clearly discernible genres of metaphor in S'ncamtho which are proverbs, sayings, aphorisms and euphemistic metaphors. While S'ncamtho and other youth varieties in Africa have been identified as urban varieties, the study brings in the dimension of measuring the spread of S'ncamtho to peri-urban and rural areas. Data from questionnaire tests, interviews and observations is analysed using the Idiom Familiarity and Comprehension Judgement Method to measure the impact and spread of S'ncamtho metaphors. The guiding theory in evaluating the spread of S'ncamtho metaphors is a Social Psychology framework- Social Impact Theory (SIT). The thesis argues that S'ncamtho metaphors spread outside Bulawayo’s high density male youth to female and older Ndebele speakers in and outside the city, it identifies male youth in the age cohort 15- 35 years as more familiar and using more S'ncamtho metaphors compared to females and older males in urban, peri-urban and rural areas. It also reveals that S'ncamtho metaphor familiarity declines with age and distance from Bulawayo, and that generally females use less S'ncamtho compared to males and the young are more familiar with S'ncamtho compared to adults. The research reveals that there is no significant difference between rural and urban professionals in S'ncamtho metaphor familiarity and this confirms that improved communication networks impact on the spread of S'ncamtho as professional people frequent Bulawayo for pay and other services. However, the study also noted that there are still more people who have negative attitudes towards S'ncamtho, compared to those who view its impact positively. The thesis argues that the popularity of S'ncamtho has seen S'ncamtho metaphors operating in professions including journalism, health professions, teaching and religious professions. Furthermore, attitudes are changing as some people have begun to view S'ncamtho positively outside the criminal prejudices.
Open Access
A Comparative Analysis of the Performance and the Microbial Ecology of Biological Sulphate Reducing Reactor Systems
(2020) Hessler, Tomas; Huddy, Robert; Harrison, Susan
Acid rock drainage (ARD) is defined as acidic waste-water contaminated with sulphate and heavy metals which is generated through the oxidation of sulphidic ores in the presence of water and oxygen. Mining activities accelerate this process by bringing these ores to the surface where they are further crushed and, eventually end up in waste rock dumps and tailing impoundments where they continue to generate ARD into perpetuity. Active mining operations are mandated to prevent the discharge of ARD into the environment. This ARD is commonly remediated by expensive yet highly effective active treatment strategies such as high-density sludge processes and reverse osmosis. South Africa has an extensive history of gold and coal mining which has left abandoned mine workings with associated waste rock dumps throughout northern and eastern parts of the country. As many of these mines have long been abandoned, the responsibility to mitigate the environmental impact of the generated ARD lies solely with government. Although these diffuse sites often generate smaller volumes of less aggressive ARD compared to that generated through mine water rebound, the sheer number and the continual ARD generation from these sites is a severe threat to South Africa's already poor water security. Biological sulphate reduction (BSR) has long been considered an attractive option for the longterm remediation of these low-volume sources of ARD – but its implementation has shown mixed success. BSR is a process catalysed through the innate metabolism of sulphate-reducing bacteria (SRB) which coexist within complex microbial communities. SRB themselves are a highly diverse group of anaerobic microorganisms which use sulphate as a terminal electron acceptor. The sulphide and bicarbonate produced during BSR can be used to precipitate heavy metals and aid in the neutralisation of the ARD, respectively. The implementation of BSR is, therefore, a comprehensive remediation strategy for diffuse sources of ARD. The study of BSR, using various reactor configurations and operating conditions shows much promise. However, the microbial ecology of the complex communities within BSR systems, and their links to the performance of BSR processes, has received far less attention in published literature. This is not a result of underappreciation of the role microbial communities but rather a historical lack of tools, specifically high-throughput techniques, available to assess complex microbial consortia. It is asserted that the success of a sustainable BSR process developed for the long-term remediation of ARD requires an in-depth understanding the microbial communities associated with this process. The identification of the microorganisms which are key to the process, thosewhich threaten the stability of the community and the optimal growth conditions of these microorganisms, can be used to inform how these bioreactors are designed and operated. This study investigated the performance and microbial ecology of several continuous BSR reactors using culture-independent metagenomic sequencing approaches. The performance and microbial ecology of these reactors were evaluated at a range of hydraulic residence times (HRT) over the course of approximately 1000 days of continuous operation, from five- through to one-day(s). The tested reactor configurations included a continuous stirred tank reactor (CSTR), an up-flow anaerobic packed bed reactor (UAPBR) and a linear flow channel reactor (LFCR) that were each operated in duplicate and supplemented with either lactate or acetate as an electron donor. The different reactor configurations and supplied electron donors, as well as the varied applied HRT, generated a range of microenvironments which were hypothesised to lead to the divergence of the initial microbial community of the inoculum and generate numerous distinct microbial communities throughout and across the reactor systems. 16S rRNA gene amplicon sequencing was used to assess the microbial community structure of the numerous populations across the reactor systems and monitor how these communities responded to the change in the applied HRT. Genome-resolved metagenomics was employed in parallel to recover the genomes of all predominant microorganisms identified through gene amplicon sequencing. This allowed the interrogation of the composition of the respective microbial communities as well as the genetic potential of each microorganism and encompassing the communities represented within specific reactor environments. The CSTRs were selected as these systems are characterised as well-mixed, support solely suspended biomass and kinetic equilibriums are achieved rapidly. This allows the performance of these reactors to be predictable and provides a benchmark to which the LFCRs and UAPBRs could be compared. The lactate-supplemented CSTR performed largely as anticipated based on available literature, demonstrating a maintained sulphate conversion of approximately 55% over the course of the study. The reactor achieved a maximum observed volumetric sulphate reduction rate (VSRR) of 17 mg/ℓ.h at a one-day HRT. The system supported a low SRB diversity, constituted almost entirely by a Desulfomicrobium and two Desulfovibrio operational taxonomic units (OTUs). The acetate-supplemented CSTR was able to maintain sulphate reducing performance at HRT where complete washout of SRB had been predicted based on literature. This reactor exhibited a maximum VSRR of 10.8 mg/ℓ.h at a 1.5-day HRT and was dominated by the same Desulfovibrio and Desulfomicrobium observed in the lactate-supplemented CSTR, along with several other SRB genera at lower abundance. The LFCRs demonstrated an approximately ten-fold greater biomass retention than the corresponding CSTRs. This was facilitated through the incorporation of carbon microfibres, whichfacilitated microbial colonisation and biofilm formation within the reactors. Surprisingly, the lactate-supplemented LFCR, underperformed compared to the lactate-supplemented CSTR, achieving a maximum VSRR of 14.8 mg/ℓ.h at a one-day HRT. This reduced performance, in spite of the enhanced biomass retention, was concluded to result from the out-competition of lactateoxidising SRB in the reactor by Veillonella and Enterobacter OTUs. The acetate-supplemented LFCR exhibited a period of underperformance before recovering and subsequently demonstrated a maximum VSRR of 17.1 mg/ℓ.h at a one-day HRT. Evaluations of the microbial communities of this system during the HRT study revealed a dramatic shift in the SRB communities from being dominated by Desulfatitalea and Desulfovibrio to being dominated predominantly by Desulfomicrobium and Desulfobacter. The UAPBRs are governed by plug-flow which resulted in the generation of gradients of decreasing substrates and increasing products throughout the height of the reactors. This, as hypothesised, resulted in the stratification of the microbial communities throughout the height of these reactors. This allowed many associations to be made between specific microorganisms and their ideal growth environments. Both UAPBRs demonstrated competitive sulphate reducing performance. The lactate-supplemented UAPBR proved especially successful as this system was able to maintain >95% sulphate conversion at one-day HRT, corresponding with a VSRR of 40.1 mg/ℓ.h. The performance of this reactor was attributed to the significant quantity of retained biomass and the successful harbouring of lactate-oxidising SRB towards the inlet zone of the reactor as well as propionate- and acetate-oxidising SRB towards the effluent zones of the reactor. The acetatesupplemented UAPBR exhibited a maximum VSRR of 23.2 mg/ℓ.h at a one-day HRT and a maximum sulphate conversion of 79% at a 2.3-day HRT. The stratification of the microbial communities within the acetate-supplemented UAPBR was less pronounced than the lactatesupplemented UAPBR, as a result of the fewer available volatile fatty acid species. However, the stratification which was observed in this system could be used to postulate the growth kinetics associated with the identified SRB – a Desulfobulbus was associated with rapid acetate oxidation in the inlet zone while a Desulfatitalea and a Desulfosarcina could be implicated in sulphate scavenging in the effluent zone of this reactor. This proved particularly valuable for elucidating the roles of these same SRB in the well-mixed reactor systems. Genome-resolved metagenomics was employed to recover the genomes of the microorganisms identified in these systems and determine the metabolic potential of these microorganisms. Hydrogen-evolving hydrogenase genes were found to be widespread in genomes not capable of sulphate reduction. In contrast, hydrogen-consuming hydrogenases as well as autotrophic gene pathways were common amongst SRB genomes. The ubiquity of hydrogenase genes in these environments indicated that inter-species hydrogen transfer was an important feature within thesemicrobial communities. The dual consumption of both acetate and hydrogen was concluded to have facilitated the maintained sulphate reducing performance of the acetate-supplemented reactor systems at short HRT where system failure had been predicted. Indices of replication (iRep) were used to estimate the instantaneous growth rates of the microorganisms from metagenomic shotgun sequencing datasets. This revealed that, at a four-day HRT, the microorganisms within the biofilms were comparably active to planktonic microorganisms. This, together with the dynamic changes in the composition of these biofilms during the HRT study, suggests these biofilms are even more active and competitive than previously thought. The combined use of next-generation gene amplicon sequencing and genome-resolved metagenomics has given unprecedented insights into the microbial communities of BSR reactor systems. Using this approach, it was possible to uncover a seldom discussed form of hydrogen cycling within BSR systems and has shown that there is no ‘one-size-fits-all' approach when inoculating BSR reactors. The SRB within these systems were often highly specialised to particular environments, specific electron donors and each showed differing growth kinetics. The success of long-term, semi-passive BSR reactor systems would benefit greatly from the tailoring of SRB inoculums informed by the chosen reactor configuration and operating conditions. The outcomes of the kinetic reactor experiments have led to several recommendations for the design and operation of these systems.
Open Access
A comparative analysis of the regulations governing mobile money services in South Africa and Zimbabwe and their impact on sustainable financial inclusion of the poor and vulnerable people
(2022) Mavhuru, Luck; Hutchison, Andrew
Mobile money services refer to service where a mobile phone is used to provide banking services with little or no involvement of traditional banks. This service has become a powerful tool for bringing unbanked and underbanked people into the formal financial sector. The roll out and success of the service in question has not been smooth in some countries due to stringent financial regulations. The purpose of this study was to conduct a comparative legal analysis of how financial regulations have enhanced or hindered mobile money services adoption in South Africa and Zimbabwe and the extent to which this has helped to increase financial inclusion. Through a comparative analysis of primary and secondary sources of law, this study observed that South Africa and Zimbabwe have contrasting mobile money services fortunes which can be attributed to the regulatory approaches adopted by the two countries towards the mobile money services. South African adopted a no regulation approach requiring any entity that engages in mobile money services to do so within the confines of existing financial regulations. As a result of this, mobile money services have made little to no contribution to the fight against financial exclusion in South Africa. On the other hand, this research found that Zimbabwe has a thriving mobile money service sector. This can be attributed to the test and learn regulatory approach adopted by the country's regulators. At the time of writing this thesis, MTN and Vodacom in South Africa are relaunching their mobile money services after discontinuing the services 5 years ago. Rigid financial regulations were fingered as one of the causes of failure of the first attempt. The author hopes in highlighting the regulatory shortfalls of the approach adopted by South Africa in regulating mobile money services, this thesis will help policy makers, regulators and industry players to develop robust and inclusive mobile money regulatory eco-systems which promote financial inclusion as is the case with Zimbabwe.
Open Access
A comparative study of China's foreign direct investment in Africa: regulation, policy, and legal cooperation
(2023) Lefifi, Tebogo; Ordor, Ada; Kalula Evance
A new era of Africa-China legal cooperation in Foreign Direct Investments (FDI) was inaugurated following the successful founding of The Forum on China Africa Cooperation (FOCAC) in 2000. In 2015, China became a capital exporter and adopted a new global strategy to reverse the hegemony comprising norm-making and advising law reforms in developing countries. However, a comprehensive approach is still lacking to determining and understanding the potential impact and influence of China's outbound FDI (OFDI) policy, laws and regulations on Africa's economic development agenda and legal environment. Previous research has interpreted China's increasing outward foreign direct investment OFDI as a byproduct of China's market- or resource-seeking agenda and failed to consider the legal aspects of the relationship. Contrarily, this study argues that China's OFDI influence introduces a novel type of south-south legal transplant that will shape prospective African legislative initiatives, ideologies, and norms. By examining China' legal transplant experience and FDI governance model ideology, this research aims to provide a comprehensive understanding of China's influence on Africa's future legal reforms. The analysis explicitly explores Africa's transplant of China's cyber sovereignty governance model. The study utilises a desktop research study methods using a combination of primary and secondary sources. The data is gathered from research from various sources in official government websites, action plans documents, academic literature, and case studies. A comparative analysis of the benefits and drawbacks of China's and Africa's experiences with FDI regulation and legal transplant are key considerations to the study. The findings of the study reveal and highlight the benefits and challenges of legal cooperation through OFDI and present recommendations for the development of laws with Africa-China characteristics. The research will guide Africa's policy response to regulating Chinese investments in the Continent and guide lawmakers in transplanting laws from China.
Open Access
A comparative study of stochastic models in biology
(1997) Brandão, Anabela de Gusmão; Zucchini, Walter; Underhill, Les
In many instances, problems that arise in biology do not fall under any category for which standard statistical techniques are available to be able to analyse them. Under these situations, specifics methods have to be developed to solve and answer questions put forward by biologists. In this thesis four different problems occurring in biology are investigated. A stochastic model is built in each case which describes the problem at hand. These models are not only effective as a description tool but also afford strategies consistent with conventional model selection processes to deal with the standard statistical hypothesis testing situations. The abstracts of the papers resulting from these problems are presented below.

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