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BODIPY dyes for application in the photo-oxidation of pollutants, photodynamic antimicrobial chemotherapy, and nonlinear optics

  • Authors: Kelechi, Lebechi Augustus
  • Date: 2020
  • Subjects: Dyes and dyeing -- Chemistry , Fluorescent probes , Fluorescence spectroscopy
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/140298 , vital:37859
  • Description: The synthesis and structural characterization of a series of BODIPY dyes to analyze both the effects of halogenations at the 2,6-positions and the introduction of styryl groups at the 3,5-positions. The photophysical properties of these dyes were investigated to determine their suitability as singlet oxygen-generating photosensitiser dyes for application in photocatalytic degradation of azo dyes and in photodynamic antimicrobial chemotherapy (PACT). Upon halogenation, the dyes showed high to moderate singlet oxygen quantum yields. The potential utility of electrospun polystyrene (PS) nanofibres embedded with halogenated BODIPY dyes for the photocatalytic degradation of Orange G and Methyl Orange from textile industry effluents were investigated. A comparison of the singlet oxygen quantum yield of the BODIPY dyes in solution and when embedded in the PS nanofibres support demonstrates that its photosensitiser properties are maintained in the nanofibre mats. The photocatalytic degradation properties of the PS nanofibres for Orange G and Methyl Orange were determined by using a 530 nm and 660 nm light-emitting diodes. The rate of photodegradation increases with both the Orange G and Methyl Orange concentrations and follows pseudo-first-order kinetics. The PACT activities of brominated BODIPYs on Escherichia coli and Staphylococcus aureus were investigated. Log reduction values of over 9 were obtained during the photoinactivation of Staphylococcus aureus. To be able to red-shift the main spectral band of the BODIPY dyes into the therapeutic window, styryl groups were introduced at the 3,5-positions through a modified Knoevenagel condensation reaction. Because the red-shifted spectral band lies above 532 nm, the second harmonic of the Nd:YAG laser, there is very minute absorption at this wavelength. One of the novel brominated BODIPY dyes was investigated for its potential utility as optical limiting materials in nonlinear optics (NLO), and the dyes demonstrated typical nonlinear absorption behaviour characterised by reverse saturable absorption (RSA) in Z-scan measurements. Excellent optical limiting parameters were obtained for third-order susceptibility and hyperpolarisability.
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Building a flexible and inexpensive multi-layer switch for software-defined networks

  • Authors: Magwenzi, Tinashe
  • Date: 2020
  • Subjects: Software-defined networking (Computer network technology) , Telecommunication -- Switching systems , OpenFlow (Computer network protocol) , Local area networks (Computer networks)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/142841 , vital:38122
  • Description: Software-Defined Networking (SDN) is a paradigm which enables the realisation of programmable network through the separation of the control logic from the forwarding functions. This separation is a departure from the traditional architecture. Much of the work done in SDN enabled devices has concentrated on higher end, high speed networks (10s GBit/s 100s GBit/s), rather than the relatively low bandwidth links (10s MBit/s to a few GBit/s) which are seen, for example, in South Africa. As SDN is increasingly becoming more accepted, due to its advantages over the traditional networks, it has been adopted for industrial purposes such as networking in data centres and network providers. The demand for programmable networks is increasing but is limited by the ability of providers to upgrade their infrastructure. In addition, as access to the Internet has become less expensive, the use of Internet is increasing in academic institutions, NGOs, and small to medium enterprises. This thesis details a means of building and managing a small scale Software-Defined Network using commodity hardware and open source tools. Core to the SDN Network illustrated in this thesis is the prototype of a multi-layer SDN switch. The proposed device is targeted to serve lower bandwidth communication (in relation to commercially produced high speed SDN-enabled devices). The performance of the prototype multilayer switch had shown to achieve: data-rates of up to 99.998%, average latencies that are under 40µs during forwarding/switching and under 100µs during routing while using packet sizes between 64 bytes and 1518 bytes, and a jitter of less than 15µs during all tests. This research explores in detail the design, development, and management of a multi-layer switch and its placement and integration in small scale SDN network. This includes testing of Layer 2 forwarding and Layer 3 routing, OpenFlow compliance testing, the management of the switch using created SDN applications, and real life network functionality such as forwarding, routing and VLAN networking to demonstrate its real world applicability.
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Chasing Eden: Margaret Atwood’s MaddAddam trilogy and the value of reading in a technological age

  • Authors: Bosman, Zoë June
  • Date: 2020
  • Subjects: Atwood, Margaret, 1939- MaddAddam trilogy , Speculative fiction -- History and criticism , Capitalism in literature , Dystopias in literature , Science fiction -- History and criticism , Technology in literature
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/145796 , vital:38467
  • Description: This thesis is focussed on Margaret Atwood’s MaddAddam trilogy: Oryx and Crake (2003) The Year of the Flood (2009) and MaddAddam (2013). Detailing Atwood’s own specifications as to why these texts should be categorised as works of speculative fiction, the thesis examines how this literary genre, and Atwood’s MaddAddam trilogy in particular, is uniquely capable of encouraging readers to interrogate critically the socio-economic, environmental, and ethical problems to which she, and the contemporary reader, bear witness in the present technological age. With reference to Atwood’s essays and critical writings, Darko Suvin’s Metamorphoses of Science Fiction, and Wolfgang Iser’s The Act of Reading, this project explores the value of reading speculative fiction and details how Atwood has constructed the fictional, yet plausible, possible future world of her trilogy by extrapolating our current scientific capabilities, environmental challenges, and political configurations to their logical conclusions. It explores the close relationship that exists between the near-future world of Atwood’s texts and the contemporary context from which she has drawn her subject matter, and argues that the trilogy demonstrates graphically the long-term consequences of capitalism, sustainability, and the doctrine of human exceptionalism, which this project, following Yuval Harari, defines as orthodox guiding narratives: fictions that humanity has created, and which structure our perception of reality and guide our behaviour. The project maintains that Atwood’s trilogy presents the reader with a hypothetical future that looks towards and beyond the end of contemporary technological society in order to urge her reader to imagine, and actualize, alternatives to the scenarios that these texts depict. The most significant question Atwood’s texts ask is whether contemporary technological society is willing and able to transform in order to avert the ecological apocalypse that is the logical conclusion to the Anthropocene?
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Chirema Chine Mazano Chinotamba Chakazendama Madziro

  • Authors: Mapondera, Wallen
  • Date: 2020
  • Subjects: Art, Zimbabwean , Art -- Economic aspects -- Zimbabwe , Artists -- Zimbabwe , Takadiwa, Moffet , Nyandoro, Gareth , Clottey, Serge Attiku , Mapondera, Wallen -- Exhibitions
  • Language: English
  • Type: text , Thesis , Masters , MFA
  • Identifier: http://hdl.handle.net/10962/147457 , vital:38638
  • Description: This mini-thesis has developed as a practice-based supporting document to the exhibition Chirema Chine Mazano Chinotamba Chakazendama Madziro. The exhibition responds to how people become innovative in finding alternative means of survival and staying relevant in an economically depressed country. Zimbabwe is often the first country that comes to mind when people talk about hyperinflation; the situation was and still is intolerable, but somehow its citizens find means to pull through. Unemployment and poverty are the main causes of physical and mental problems for an individual. With this thesis, I highlight the innovations employed by Zimbabweans as a way of keeping themselves busy. I approach this through analysing the Zimbabwean general public’s creative reactions, and by tracing Zimbabwean visual artists’ use of found objects as a reaction to the country’s economic hardships. As people have been pushed to find alternative ways of survival, Zimbabwean artists in particular also shifted from using conventional art materials due to their unavailability. They began to redefine what art material is by employing objects in their artworks that previously had a non-art function. As such, there is a growing need to recognise, classify and document the shifts and establish platforms to generate growth of these innovations. In this minithesis I discuss my own practice, and I analyse the works of Moffat Takadiwa, Gareth Nyandoro and Serge Attiku Clottey.
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Choreographies of protest performance as recruitment to activism and the movement of perception during the 2015 re-emergence of student activism at Rhodes University

  • Authors: Qoza, Phiwokazi
  • Date: 2020
  • Subjects: College students -- Political activity -- South Africa , Student protesters -- South Africa , Student movements -- South Africa , Higher education and state -- South Africa , Performance art -- Political aspects -- South Africa , Protest songs -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/141692 , vital:37997
  • Description: It has been argued that individuals participate in activism due to an identification with the preferences and interests of an emerging group of actors or in solidarity with a pre-existing network that has resorted to a number of protest repertoires in order to make claims or demands. Additionally, an emerging instance of protest is often linked to an image of previous protest events through the employment of a combination of master frames which function as discursive articulation of the encounter in familiar terms, creating a frame resonance which recruits adherents and constituents. To understand why some bystanders to protest transcended to actors in protest and the development of frames within a protest cycle, a performance ethnography is employed to observe and analyse choreographies of protest which took place at an institution of higher education in South Africa during the 2015 re-emergence of wide-spread student activism. It is found that in encountering an atmosphere of protest there emerged a relation of feeling, referred to as “feeling the vibe or atmosphere”, which those who became protest performers resolved in ways which increased their capacity to act in favour of co-constituting that atmosphere. During the encounter between the bystander body and the atmosphere of protest, non-linear somatic communication, characterised by active and passive gestures and postures, occurred through which protest performers developed contact and connection with other bodies as a result of the displacement of space. This thesis suggests that participation in activism can be about going with the flow of movement in an uncertain and ambiguous moment and is not limited to an identification with the pre-existing organization of preferences and interests as a frame of resonance emerges to signify somatic communication which differentiated bodies in the duration of protest performance. Therefore, this thesis uses the theory of affect to situate student activism in-between the politics of performance and the performance of politics whereupon the rhythm of song creates an opening for the kinaesthetic to create form from spontaneous movement of the body as an event of the movement of perception and the perception of movement.
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Combination ecosystem green engineering and early life history processes to enhance the intertidal biodiversity in the Port of East London

  • Authors: Mafanya, Sandisiwer
  • Date: 2020
  • Subjects: Biotic communities -- South Africa -- East London , Perna -- Ecology --South Africa -- South Africa-- East London , Mexilhao mussel -- Ecology -- South Africa -- East London , Habitat (Ecology) -- Modification -- South Africa -- East London , Benthic animals -- Effect of habitat modification on -- South Africa -- East London , Harbors -- Environmental aspects -- South Africa -- East London
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/166376 , vital:41357
  • Description: Marine coastal ecosystems are highly impacted by anthropogenic activities, including the development of, and practices within, harbours and/or ports. Artificial structures associated with harbours have a different chemical composition, texture and orientation than that of the natural benthic habitats they have replaced, and are therefore not generally favourable for the settlement and occurrence of indigenous species. Attempts are being made to identify what structures and materials can be used to aid in the rehabilitation of native species within harbours. The aim of this study was to investigate the effects of utilising environmentally-friendly artificial structures (tiles) with varying complexity (crevices and ridges with different depths) with ecological engineers (the indigenous bivalve Perna perna), on the associated benthic biodiversity within an international port in South Africa (Port of East London). The objectives of the study were to test the effects of artificial habitat complexity and the presence of bivalves on 1) the growth, mortality and biomass of a selected model species of ecosystem engineer (P. perna), and 2) the associated intertidal biodiversity. Tiles seeded with bivalves (P. perna) were deployed at two sites in the Port of East London and monitored monthly over a period of 12 months (November 2016-October 2017) to assess survival, growth and associated biodiversity. Environmental variables were also measured every month. The results of the three-way repeated measures ANOVAs indicated that tile treatment (especially high complexity of 2.5 and 5 cm) had an effect on the diversity of mobile species, length, height and biomass of the bivalves used as model ecosystem engineer, indicating the potentials for protection from wave dislodgement and refuge provision. Treatment (especially flat tiles) also had an effect on sessile/sedentary species diversity, indicating the greater proportion of space provided by these non-complex tiles. In addition, month had an effect on the mortality, height and biomass of the bivalves. Mortality was highest in October 2017, while the growth in height and biomass of P. perna were largest in January and October 2017 respectively. The use of artificial tiles also had a positive effect on the survival, growth, and biomass of bivalves (especially the length, weight and dry weight in 2.5 cm and 5 cm complexity). Additionally, this research investigated patterns of settlement and recruitment of the local bivalve population (P. perna) in the Port of East London and adjacent natural coastline to understand the early life history temporal and spatial dynamics of this model ecosystem engineer species. Settlement and recruitment were assessed every month by deploying and replacing artificial collectors for a total period of 19 months (November 2016-May 2018). The results of the two-way ANOVAs indicated that month and site (port vs natural) had an effect on settlement and recruitment of bivalves. Settlement and recruitment of bivalves were highest in July 2017 (port) and March 2018 (natural rocky shore). This study has highlighted that the use of artificial concrete tiles with increased complexity, as well as the investigation of the early stages of mussel populations could be important to consider in a framework of rehabilitation of urban coastal environments such as the Port of East London. Ecological engineering (in terms of increased complexity and heterogeneity) has indeed the potentials to be incorporated in South African programmes aiming at improving natural biodiversity in coastal urban environments. Nonetheless, the spatio-temporal variability of early driver of mussel populations (settlement and recruitment) is also an important feature to be closely monitored if biodiversity in South African coastal armouring is to be enhanced effectively and in the long term.
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Combining DNA barcoding and morphology to identify larval fishes from the nearshore environment off the south-east coast of South Africa

  • Authors: Somana, Zinzi Sinazo
  • Date: 2020
  • Subjects: Fishes -- Larvae -- South Africa -- Identification , Fishes -- Genetics -- Research -- Technique , Fishes -- South Africa -- Classification , Genetic markers
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/144605 , vital:38362
  • Description: The early life history stages of most marine fish species are undescribed. The problem is, most of these fishes have pelagic larvae which are minute, delicate forms. Linking the larval stage to an adult counterpart is extremely challenging as larvae are morphologically different from the adults. Historically, larval fish identification relied solely on distinguishing morphological characteristics and meristic measurements, which has resulted in taxonomic confusion and misidentification. The introduction of the deoxyribonucleic acid (DNA) barcoding technique as an alternative approach has been successful in positively identifying larval fishes. The correct identification of larval specimens is the key to a better understanding of larval ecology, which underpins the success of any adult fish population. This study aimed to positively identify larval fishes of the south-east coast of South Africa using morphological characteristics and DNA barcoding. Larval and eggs specimens for this study were collected from the shallow nearshore waters of the south-east coast of South Africa. A total of 177 larval specimens were used for morphological analysis. Body shape, gut shape, pigmentation and morphometric measurements (such as body depth, preanal length and total body length) were used to identify each specimen to the family level. In addition, a fragment of mitochondrial cytochrome c oxidase subunit 1 gene (COI) was adopted for sequencing to identify larval fish specimens and fish eggs. Sequences generated from this study were compared to those in the Barcode of Life Database (BOLD). When there were no close matches to a sequence, the GenBank nucleic acid sequence database, maintained by the National Center for Biotechnology Information (NCBI), was used as an alternative. A total of 18 different families were identified through morphology. Seventy-seven of the 177 larval specimens were not subjected to morphological identification due to physical damage. The majority of larvae identified using morphological characteristics belonged to either the Sparidae, Tripterygiidae or Gobiesocidae fish families. Through DNA barcoding, 12 fish families, 16 genera and 18 different species were identified. Ten DNA barcodes (categorised as ‘no match’) from 10 different larval specimens were not identified through any of the online databases. Therefore, the 2% threshold value was used to identify members of the same species. The K2P genetic distance relationships were calculated among the no match sequences and downloaded probability matches from NCBI. This resulted in two unknown specimens assigned to the Blenniidae and Gobiidae. All other taxa were identified to species level, except specimens representing the Gobiidae and Tripterygiidae families. Based on the K2P genetic distances Gobiidae representatives were categorised as members of the Caffrogobius genus. Twenty-eight barcodes represented specimens from the Tripterygiidae. DNA barcode data from COI was analysed using the standard phylogenetic procedures in MEGA6 to examine relationships and differentiation among sequences. These could not be identified to the lowest taxonomic rank due to limited sequence data to compare them with. The sequence data from these specimens gave different results in the two online databases. BOLD results were to family level (Tripterygiidae) and NCBI to the species level (Clinidae: Pavoclinus profundus). Results in this study confirmed the efficiency of the DNA barcoding technique in species level identification of fish larvae. The evidence from genetic barcodes of the Tripterygiidae specimens, supported by morphological characteristics, suggests the need for thorough research to identify the individuals to the species level. The fact that this study identified taxonomically problematic Gobiidae and Tripterygiidae specimens suggests that studies similar to this may highlight additional diversity and help to resolve the taxonomy of other species in these families. However, the lack of reference sequence data from the adult specimens, and especially those with cryptic diversity, were both shortcomings for the positive identification of larvae. With that being said, it shows the necessity for more research to be conducted on barcoding of larvae in general as to accommodate all kinds of species from biodiversity to economic perspectives.
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Come listen quickly

Commonplaces

  • Authors: Orsmond, Joseph Granger
  • Date: 2020
  • Subjects: South African fiction (English) -- 21st century
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/144061 , vital:38307
  • Description: My thesis is a collection of short to medium length poems. All of the subject matter is sustained by reflections, anecdotes or stories. The pieces in the collection are concerned with experiences linked to the seemingly ordinary and mundane. In this regard, I am inspired by how Alan Ziegler (in “Tales of Teaching” and Love at First Sight) and Raymond Carver (All of Us: The collected Poems) find stories in subject matter which is so commonplace, that it is often ignored creatively. Likewise, the lyricism and modes of expression of William Carlos Williams, Federico García Lorca and Luis Cernuda have informed how I write and structure my poetry.
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Constructions of United States government development funding in response to the global gag rule

  • Authors: Molobela, Reabetswe Lee-Anne
  • Date: 2020
  • Subjects: Pro-choice movement -- South Africa , Abortion -- Law and legislation -- South Africa , Abortion -- Moral and ethical aspects -- South Africa , Abortion -- Psychological aspects , Reproductive rights -- South Africa , Economic assistance, American -- South Africa , Non-governmental organizations -- South Africa , Discourse analysis , Social constructionism , Global Gag Rule
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/148295 , vital:38727
  • Description: Despite South Africa’s progressive abortion law, barriers to safe abortion are numerous and exist at both the macro and micro level. Barriers include abortion stigma, discrimination, strong moral judgements against abortion within society and conscientious objection among health care workers. Furthermore, women’s lack of knowledge regarding the legal status of abortion and the voluminous illegal advertisements of back street abortions undermines the legislation and promotes unsafe abortions. Sexual and reproductive health rights (SRHR) non-governmental organizations (NGOs) have served as a link between service and people by providing information about safe abortion to women, especially in rural areas and have received funding from various platforms including United States government. However, the United States government has established the global gag rule which forbids foreign non-governmental organizations receiving United States government funding from using United States government and non-United States funds for abortion related activities. The global gag rule has been reinstated and extended by the current United States president. As such the global gag rule is expected to have an adverse effect on sexual and reproductive health rights in South Africa and on Sexual and reproductive health rights non-governmental organizations. The aim of the study is to highlight the constructions and responses to the global gag rule by sexual and reproductive health rights non-government organization workers in the South African context. This study used semi-structured individual interviews to collect data through purposive and snowball sampling of 10 South African Sexual and reproductive health rights non-governmental organizations workers. The study is situated within the social constructionist framework with emphasis on Fairclough’s three aspects of the constructive effects of discourse as an analytic tool in conjunction with Braun and Clarke’s social constructionist thematic analysis. The results of the study reflect on participants’ construction of United States government as imposing conservative agendas and taking regressive steps towards Sexual and reproductive health rights, which have in turn invoked indirect and direct resistance from non-governmental organizations. Additionally, NGO workers have constructed subject positions that highlight the vulnerability of non-governmental organizations dependency on United States government 1funding as it destabilizes and fragments civil society organization while it compromises the effectiveness of non-governmental organizations in serving the needs of intended communities. United States government is also constructed as strengthening abortion stigma and strengthening barriers to safe abortion that already exist in the country.
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Creative production and existential thought: a feminist existential analysis of South African visual artist Berni Searle’s artwork

  • Authors: Mokwena, Palesa
  • Date: 2020
  • Subjects: Women artists -- South Africa , Women artists, Black -- South Africa , Existentialism and art , Feminism and art -- South Africa , Searle, Berni
  • Language: English
  • Type: text , Thesis , Masters , MFA
  • Identifier: http://hdl.handle.net/10962/148005 , vital:38701
  • Description: Through an analysis of the work of South African artist Berni Searle, my study will investigate feminist existential ideas and concepts that have been explored by various creative producers in and outside of Europe/South Africa through different forms of creative productions and under different epistemological categories. ‘Canons’ of European existentialist/feminist thought often exclude the existence of feminist existential knowledge productions and producers outside of Europe. In conducting this study, I am responding to the past and present separatist and identitarian categorisations of creative productions from black/African creative producers, particularly women creative producers in South Africa, creating an alternative canonisation around their selected works. Although canons have been and can be used to drive separatist and identitarian categorisations, it is my hope to elucidate a discourse around the preservations and acknowledgements of South African creative and knowledge productions through a feminist existential framework that canonises important black feminist existentialist works and thereby brings to light their intellectual contributions over and above their identities. My development of a South African feminist existentialism is an attempt to graft a more intersectional, holistic framework to introduce in the feminist and existential discourses, and to proffer a new intersectional holistic paradigm of discussing categories that do not limit creative productions. To frame this research, I will reflect on the politics of historical and contemporary South African society as it is reflected in the works of the chosen creative producers and theorists and to question how we respond as creative feminist existentialists to contemporary South African struggles and how such a lens can be activated as a creative-theoretical tool of investigation.
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Critical success factors in implementing projects on restituted land parcels in South Africa

  • Authors: Whiting, Christoper Whiting
  • Date: 2020
  • Subjects: Community development -- Management -- South Africa , Community development -- Management -- South Africa -- Case studies , Economic development projects -- Management -- South Africa , Economic development projects -- Management -- South Africa -- Case studies , Land reform -- South Africa -- Economic aspects , Land reform beneficiaries -- South Africa -- Case studies , Restitution -- South Africa -- Case studies
  • Language: English
  • Type: text , Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/167697 , vital:41504
  • Description: Currently there is a perception in South Africa that projects undertaken on parcels of restituted land are experiencing a much higher failure than success rate. There are, however, a few projects that are reaping the rewards and uplifting their communities, as intended by the land redistribution program. One community in particular, located in Mpumalanga, called community A, is presently undertaking a development project. This development project is one of the most successful restituted land parcel projects ever in South Africa. The purpose of the study is to determine the critical success factors in this community development project that have allowed it to enjoy such high levels of success. Are these critical success factors different from the generic industry critical success factors and, if so, what are they? As informed through literature, the critical success factors focused on in this study are as follows: the influence of management, project communication, knowledge management, the role of senior management, business strategy, project success measurements, and training and development. For the empirical study, a physical questionnaire was handed to 35 management members currently employed in the community development project. The questionnaire requested the demographics of all participants and asked them to rate, using a five-point Likert scale, their perceptions of the present project activities and of the importance of the project activities mentioned in making the project successful. Participants had to indicate the extent to which they agreed with each statement in the questionnaire. The responses obtained from the survey were presented and analysed. The study found that the critical success factor “role of senior management” was the largest problem area in the restituted land development project. “Training and development opportunities” came in second, with both factor areas showing large variances. Recommendations have been given on how to address both these problematic areas in the development project and how future restituted land parcel projects can better utilize these factors to ensure successful project implementation and long-term project success.
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Crossing shades

  • Authors: Singh, Shareen
  • Date: 2020
  • Subjects: South African fiction (English) -- 21st century
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/145049 , vital:38404
  • Description: This collection of stories draw on culture, history, memory, musings and imagination. The stories are set primarily in South Africa but includes travels to other countries. I explore journeys to different worlds and minds. I challenge the reader to see how place and time influence our ways of seeing, living and evolving. I use different forms and tones that resonate with the subjective nature of each creative piece. My writing includes formal prose as well as works that experiment with fragments, vignettes and flash fiction.
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Cyclooxygenase-1 as an anti-stroke target: potential inhibitor identification and non-synonymous single nucleotide polymorphism analysis

  • Authors: Muronzi, Tendai
  • Date: 2020
  • Subjects: Cerebrovascular disease , Cerebrovascular disease -- Treatment , Cerebrovascular disease -- Chemotherapy , Cyclooxygenases , High throughput screening (Drug development) , Drug development , Molecular dynamics , South African Natural Compounds Database , ZINC database
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/143404 , vital:38243
  • Description: Stroke is the third leading cause of death worldwide, with 87% of cases being ischemic stroke. The two primary therapeutic strategies to reduce post-ischemic brain damage are cellular and vascular approaches. The vascular strategy aims to rapidly re-open obstructed blood vessels, while the cellular approach aims to interfere with the signalling pathways that facilitate neuron damage and death. Unfortunately, popular vascular treatments have adverse side effects, necessitating the need for alternative chemotherapeutics. In this study, cyclooxygenase-1 (COX-1), which plays a significant role in the post- ischemic neuroinflammation and neuronal death, was targeted for identification of novel drug compounds and to assess the effect of nsSNPs on its structure and function. In a drug discovery part, ligands from the South African Natural Compounds Database (SANCDB-https://sancdb.rubi.ru.ac.za/) and ZINC database (http://zinc15.docking.org/) were used for high-throughput virtual screening (HVTS) against COX-1. Additionally, five nsSNPs were being investigated to assess their impact on protein structure and function. Three of these SNPs were in the COX-1 dimer interface. Molecular docking and molecular dynamics simulations revealed asymmetric nature of the protein. Several ligands, peculiar to each monomer, exhibited favourable binding energies in the respective active sites. SNP analysis indicated effects on inter-monomer interactions and protein stability.
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Decent work and informal employment: the case of Bulawayo Metropolitan Province (Central Business District) Zimbabwe

  • Authors: Bob, Shaka Keny
  • Date: 2020
  • Subjects: Labor -- Zimbabwe , Informal sector (Economics) -- Zimbabwe , Job creation -- Zimbabwe , Poor -- Zimbabwe -- Employment , Labor policy -- Zimbabwe , Football coaches -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/115241 , vital:34104
  • Description: Zimbabwe, similar to other developing countries experiences a high level of informal employment. However, most informal jobs are situated in very poor working conditions and are characterised by decent work deficits. Despite the fact that various studies have shown the importance of the informal economy in that it provides livelihood earning opportunities for the majority of people in the Global South, it has remained a largely forgotten sector in policy making in most countries. It is, therefore, important that informal work be taken seriously and efforts must be made to improve working conditions for the urban working poor in the developing world. The purpose of this study is to investigate on the self-reported experiences of informal workers to understand their perspectives surrounding the concept of decent work in the Zimbabwean context. The case study is the Bulawayo metropolitan province, and this study targeted informal workers who trade within the central business district. The study also aimed to measure the decent work deficit scores between two economic sectors (food and clothing traders). This was done by testing the suitability of the Edward Webster Decent Work Deficit Index as a methodology of measuring decent work at a micro level. The analysis is based on a mixed methods study which was carried out through the use of a semi-structured survey. The study revealed that decent work for the sampled informal workers meant work related improvements, insurances and risk management, right of expression and business advancement skills which closely resembles the International Labour Organisation's conceptualisation of decent work. The study also highlighted that childcare assistance and disability insurance are concepts which remained excluded in the current conceptualisation of decent work. The thesis offers a new policy angle which shows that to promote decent work the concept of heterogeneity must be adopted because inequalities persist within the informal economy. The study also suggested that the Edward Webster Decent Work Deficit Index can be used as an appropriate methodology of monitoring the progress towards achieving decent work at the micro level i.e. industry or individual level. This is because since the formation of the decent work concept; the International Labour Organisation has only provided a methodology of how to measure the progress of decent work at the county level. The survey findings revealed that food vendors scored more poorly on the decent work deficit index compared to the clothing traders. The study also identified that food vendors and clothing traders are faced with different challenges which suggests that policy makers must take that into consideration when attempting to design policies or programmes which are aimed at assisting informal workers.
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Default in payment, an application of statistical learning techniques

  • Authors: Gcakasi, Lulama
  • Date: 2020
  • Subjects: Credit -- South Africa -- Risk assessment , Risk management -- Statistical methods -- South Africa , Credit -- Management -- Statistical methods , Commercial statistics
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/141547 , vital:37984
  • Description: The ability of financial institutions to detect whether a customer will default on their credit card payment is essential for its profitability. To that effect, financial institutions have credit scoring systems in place to be able to estimate the credit risk associated with a customer. Various classification models are used to develop credit scoring systems such as k-nearest neighbours, logistic regression and classification trees. This study aims to assess the performance of different classification models on the prediction of credit card payment default. Credit data is usually of high dimension and as a result dimension reduction techniques, namely principal component analysis and linear discriminant analysis, are used in this study as a means to improve model performance. Two classification models are used, namely neural networks and support vector machines. Model performance is evaluated using accuracy and area under the curve (AUC). The neuarl network classifier performed better than the support vector machine classifier as it produced higher accuracy rates and AUC values. Dimension reduction techniques were not effective in improving model performance but did result in less computationally expensive models.
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Design, formulation and evalauation of liposomes co-loaded with human serum Albumin and Rifampicin

  • Authors: Bapolisi, Alain Murhimalika
  • Date: 2020
  • Subjects: Liposomes , Serum albumin , Rifampin , Mycobacterium tuberculosis
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/161780 , vital:40670
  • Description: Tuberculosis (TB) is a devastating infectious disease caused by Mycobacterium tuberculosis and is the leading cause of death from a single infectious agent. The high morbidity and mortality rates of TB are partly due to factors such as the lengthy regimen (of 6–24 months), the development of drug resistance, and the pathogen location within the macrophages. These, with poor physiochemical properties of existing drugs hamper the effectiveness of the treatment despite the existence of potent antibiotics such as Rifampicin (Rif). Hydrophobicity plagues many drugs, including Rif, which are then particularly affected due to inherently poor intracellular availability. Novel drug delivery approaches are therefore needed in order to optimize the cytotoxic potential of said antitubercular drugs. To improve the bioavailability of hydrophobic drugs, numerous delivery strategies have been developed. Amongst these, the coordination of cytotoxic drugs to therapeutic proteins have shown some success for improved efficacy in the management of illnesses including infectious diseases. Of therapeutic proteins, Human Serum Albumin (HSA) is an attractive drug carrier with interestingbenefits such as low immunogenicity, antioxidant properties and improving cellular uptake ofdrugs through HSA-specific binding sites which are expressed on most cells including macrophages, where M. tuberculosis often resides. Hence, combination of Rif to HSA (Rif-HSA)seems a promising approach for improved intracellular delivery of Rif. However, the in vivo stability of colloidal protein-based therapeutics is mostly challenging and an effective vehicle is needed to control the biological fate of such conjugates.Liposomes seem to be appropriate carriers for the Rif-HSA complex due to their reputable applicability for encapsulating diverse materials (i.e., hydrophobic and hydrophilic compounds or small and complex molecules) and preventing chemical and biological degradation of the cargo. Therefore, the main objective of this study was to simultaneously encapsulate Rif and HSA in liposomes, which, to the best of our knowledge, has not been done before. The dual liposomes (Rif-HSA-lip) were made by a modified “Reverse Phase Evaporation” method (REV), following a Design of Experiments (DOE) approach to determine which factors impact the formulation. In addition, liposomes were made from crude soybean lecithin (CSL), rather than expensive and highly purified lipids. The liposomes were fully characterised, and the encapsulation efficiency (î) was monitored using high-performance liquid chromatography (HPLC). The results were correlated with factors such as organic and aqueous phase composition, as well as the in vitro release profile of Rif. Transmission electron microscopy (TEM) results confirmed the formation of spherical dual liposomes nanoparticles of roughly 200 nm. Dynamic light scattering (DLS) and Zeta potential measurements showed a negative charge (<–45 mV) and with satisfactory polydispersity (PDI<0.5). HSA dramatically improved the aqueous solubility of Rif (from1.9 mg/ml in water to around 4.3 mg/ml in HSA 10% solution) mainly due to Rif-HSA hydrophobic interactions. This resulted in a good î of almost 60% for Rif, despite the presence of bulky HSA in the lipid bilayer. These details were confirmed using proton nuclear magnetic resonance (1H NMR) and Fourier-transform infrared spectroscopy (FTIR). Furthermore, energy dispersive X-ray (EDX) and DLS data suggested the presence of HSA poking out on the surface of liposomes, which is encouraging for potential targeted delivery in the future. The in vitro release studies also depicted a substantial improvement in the diffusion of Rif in dual liposomes versus free Rif, from 65% after 12 hours for free Rif to 95% after only 5 hours for Rif- HSA-lip. Finally, stability studies conducted over 30 days at room temperature, showed that the freeze-dried formulations of Rif-HSA-lip exhibited good shelf stability over liposomes with no HSA. This study represents an illustrative example of co-loading of antibiotics and proteins into liposomes, which could encourage further development of novel nanoparticulate tools for the effective management of both drug-susceptible and -resistant infectious diseases such as TB.
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Design, formulation and evaluation of liposomes co-loaded with human serum albumin and rifampicin

  • Authors: Bapolisi, Alain Murhimalika
  • Date: 2020
  • Subjects: Liposomes , Rifampin , Antitubercular agents , Serum albumin , Albumins , Tuberculosis -- Treatment
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/163179 , vital:41016
  • Description: Tuberculosis (TB) is a devastating infectious disease caused by Mycobacterium tuberculosis and is the leading cause of death from a single infectious agent. The high morbidity and mortality rates of TB are partly due to factors such as the lengthy regimen (of 6–24 months), the development of drug resistance, and the pathogen location within the macrophages. These, with poor physiochemical properties of existing drugs hamper the effectiveness of the treatment despite the existence of potent antibiotics such as Rifampicin (Rif). Hydrophobicity plagues many drugs, including Rif, which are then particularly affected due to inherently poor intracellular availability. Novel drug delivery approaches are therefore needed in order to optimize the cytotoxic potential of said antitubercular drugs. To improve the bioavailability of hydrophobic drugs, numerous delivery strategies have been developed. Amongst these, the coordination of cytotoxic drugs to therapeutic proteins have shown some success for improved efficacy in the management of illnesses including infectious diseases. Of therapeutic proteins, Human Serum Albumin (HSA) is an attractive drug carrier with interesting benefits such as low immunogenicity, antioxidant properties and improving cellular uptake of drugs through HSA-specific binding sites which are expressed on most cells including macrophages, where M. tuberculosis often resides. Hence, combination of Rif to HSA (Rif-HSA) seems a promising approach for improved intracellular delivery of Rif. However, the in vivo stability of colloidal protein-based therapeutics is mostly challenging and an effective vehicle is needed to control the biological fate of such conjugates. Liposomes seem to be appropriate carriers for the Rif-HSA complex due to their reputable applicability for encapsulating diverse materials (i.e., hydrophobic and hydrophilic compounds or small and complex molecules) and preventing chemical and biological degradation of the cargo. Therefore, the main objective of this study was to simultaneously encapsulate Rif and HSA in liposomes, which, to the best of our knowledge, has not been done before. The dual liposomes (Rif-HSA-lip) were made by a modified “Reverse Phase Evaporation” method (REV), following a Design of Experiments (DOE) approach to determine which factors impact the formulation. In addition, liposomes were made from crude soybean lecithin (CSL), rather than expensive and highly purified lipids. iv The liposomes were fully characterised, and the encapsulation efficiency (î) was monitored using high-performance liquid chromatography (HPLC). The results were correlated with factors such as organic and aqueous phase composition, as well as the in vitro release profile of Rif. Transmission electron microscopy (TEM) results confirmed the formation of spherical dual liposomes nanoparticles of roughly 200 nm. Dynamic light scattering (DLS) and Zeta potential measurements showed a negative charge (<–45 mV) and with satisfactory polydispersity (PDI<0.5). HSA dramatically improved the aqueous solubility of Rif (from1.9 mg/ml in water to around 4.3 mg/ml in HSA 10% solution) mainly due to Rif-HSA hydrophobic interactions. This resulted in a good î of almost 60% for Rif, despite the presence of bulky HSA in the lipid bilayer. These details were confirmed using proton nuclear magnetic resonance (1H NMR) and Fourier-transform infrared spectroscopy (FTIR). Furthermore, energy dispersive X-ray (EDX) and DLS data suggested the presence of HSA poking out on the surface of liposomes, which is encouraging for potential targeted delivery in the future. The in vitro release studies also depicted a substantial improvement in the diffusion of Rif in dual liposomes versus free Rif, from 65% after 12 hours for free Rif to 95% after only 5 hours for Rif- HSA-lip. Finally, stability studies conducted over 30 days at room temperature, showed that the freeze-dried formulations of Rif-HSA-lip exhibited good shelf stability over liposomes with no HSA. This study represents an illustrative example of co-loading of antibiotics and proteins into liposomes, which could encourage further development of novel nanoparticulate tools for the effective management of both drug-susceptible and -resistant infectious diseases such as TB.
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Detecting the transnational space: metaphysical detecting in Kazuo Ishiguro’s When we were orphans, Michiel Heyns’s Lost ground, and Amitav Gosh’s The Calcutta chromosome

  • Authors: Botes, Niki
  • Date: 2020
  • Subjects: Literature and transnationalism , Detective and mystery stories -- History and criticism , Ishiguro, Kazuo, 1954- , Ishiguro, Kazuo, 1954- -- When we were orpahns , Heyns, Michiel , Heyns, Michiel -- Lost ground , Ghosh, Amitav, 1956- , Ghosh, Amitav, 1956- -- The Calcutta chromosome
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/140971 , vital:37933
  • Description: The transnational detectives in the three primary texts under scrutiny—Kazuo Ishiguro’s When We Were Orphans, Michiel Heyns’s Lost Ground, and Amitav Ghosh’s The Calcutta Chromosome—are regarded as metaphysical detectives in this thesis. As transnational figures, they criss-cross physical and national borders, but their investigations also often require the crossing of epistemological and ontological borders, as well as thinking outside of binaries. The fictional transnational, postcolonial worlds presented in these texts all feature a lack of change and the persistence of the socio-economic inequalities and discriminations of the colonial or, in the case of Lost Ground, the apartheid past. This thesis will argue that the three texts foreground the inability to break free from conceptual frameworks and a lack in human relationships as two possible reasons why the communities and societies in question have not been able to affect change. To solve the various mysteries in the texts, the transnational detectives need to find new ways of knowing and being. The lessons that these detectives learn and the personal changes they experience serve as synecdoche for how a better tomorrow for the transnational, postcolonial world could possibly be achieved. The methodology employed in this thesis involves a comparative reading of the three primary texts. To analyse and interpret these texts, this thesis draws on the philosophies of postmodern philosophers such as Martin Heidegger, Michel Foucault, Jacques Derrida, and Emmanuel Levinas, as well as postcolonial theorists like Edward Said, Gayatri Chakravorty Spivak, and Homi K. Bhabha. The thesis will contend that especially Derrida’s work on deconstruction, which forms the conceptual basis for Bhabha’s notion of the ‘third space,’ as well as Levinas’s anti-totalitarian approach with regard to the ethical relationship between the self and the other, are viable better ways of knowing and being in the transnational, postcolonial worlds presented in the texts. Derrida’s notion of différance and the trace, as well as Bhabha’s third space, this thesis contends, completely destabilises binary thinking and offers ways to think outside of the limited frameworks of ideological discourse. This thesis also posits that Levinas’s metaphysical and pluralistic interpretation of how the self should, and can, relate to the other, presents a better way of forming human relationships and has the potential to affect positive change.
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Developing an organisational culture in support of organisational capacity for change: the case of a South African bank

  • Authors: Dhoba, Howard
  • Date: 2020
  • Subjects: Corporate culture , Bank management , Organizational change
  • Language: English
  • Type: text , Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/141247 , vital:37956
  • Description: Business organisations are increasingly being exposed to challenging environmental pressures. It has been widely acknowledged and observed that an organisation that crafts an effective organisational culture should be well positioned to react to these threatening changes, and to proactively seize opportunities to adapt and learn. This research study seeks to investigate how an organisational culture that supports organisational capacity for change can be developed. It analyses what a banking organisation’s espoused culture is made up of and how it was formulated. A thematic analysis of how the bank’s aspirational and innovative culture contributes to the organisation’s capacity for change is also presented. Organisational management should take a leading role in developing the values and practices that foster participation, which are then imparted to the entire organisation. The research study thus only focused on analysing the development of organisational culture from the management perspective. An interpretivist research approach was adopted, with a case study design as the research method. Data was gathered through conducting personal interviews with twelve managers from a Retail and Business Banking cluster of one of the big South African banks. Numerous interventions were employed in the organisation to develop espoused values, aspirational culture and to encourage all employees to champion innovations and constantly search for better ways to offer delighting value propositions to clients. The research findings can assist managers and organisational leaders in building their organisational capacity for change through developing an effective organisational culture that supports change initiatives. Since the research study only focused on analysing the development of organisational culture from the perspective of management, further research studies may involve employees as well, due to the fact that everyone is expected to take an active role for an organisation to display the overall capability to effectively respond to a progressively volatile environment. The research was able to reveal how key initiatives that are designed from theoretical constructs can be used to deliver on an innovative organisational culture that contributes to organisational capability for change.
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