Geology, regional diamond exploration and diamond provenance of the proterozoic diamondiferous Umkondo conglomerates, Umkondo group, eastern Zimbabwe
- Authors: Zhou, Takawira
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3598 , vital:20528
- Description: The Umkondo Sedimentary Basin in eastern Zimbabwe has been studied by various individuals and organizations since 1901. Their interest had been in finding limestone and beryl and base metal deposits, especially copper, iron and uranium, but these occurrences had proved to be of no economic value (Watson, 1969). The recent discovery of placer diamonds within the Proterozoic basal conglomerates of the Umkondo Sedimentary Basin has now attracted worldwide interest in the basin’s diamond economic potential, in understanding of the geology, and the diamond provenance of the Umkondo conglomerates. The Umkondo Sedimentary Basin basal conglomerate placer deposit might narrowly be defined as a mega-placer because of its sheer large size and high grades, especially on the 70,000 hectare western margin diamond dispersion halo where alluvial diamonds are being mined. Bluck, et al., (2005, pp 213) defines a diamond mega-placer as: . . . a number of linked deposits that are a result of one or a continuous process of transportation and deposition and holds or have held at least >= 50 million carats at >= 95% gem quality, for example, the Orange-Vaal dispersal, off the Kaapvaal craton in South Africa. On craton placers are residual, and transient placers are eroded and deposited into the exit drainage, while terminal placers, the final depositories of diamonds with the highest chances of being mega-placers are deposited into terminal basins like oceans and foreland basins. Though data is limited at the moment, the Umkondo conglomerates caratage is likely to run into hundreds of millions of carats, with a diamond gem content of between twenty and twenty-five percent, as is indicated from recent diamond production data. The greater part of the Umkondo diamonds are likely to be lodged beneath the deep gravels of the Middle and Lower Save River basin, because small remnant tilted mountain blocks and inselbergs forming the caps of hills are what remains of the host conglomerate on the western margin of the Umkondo Basin. Areas to be examined in this document will be the geology; the mode of formation of the Umkondo basin and its sedimentary system; the regional kimberlite exploration around the basin; and diamond production in the Marange diamond field, in order to come up with indications of the provenance of the diamonds within the Umkondo conglomerates. The kimberlite clusters in and around the Umkondo sedimentary basin have all proved to be barren or only nominally diamondiferous and that the kimberlites are between 200Ma and 500Ma and thus much younger than the greater than 1.1Ga Umkondo diamondiferous conglomerates. Studies so far undertaken have not managed to point to the origin, or provenance, of the Umkondo or Marange diamonds, which were discovered on the western edge of the Umkondo Basin and in the east of the basin below the Chimanimani Mountains along the Haroni River. This paper is an attempt to clear up some of the misconceptions surrounding the Marange diamond deposit and to raise interest in the urgent rquirement to study and understand the Umkondo Basin and the origin of its diamonds. The only meaningful studies on diamond occurrence and diamond exploration of the basin were undertaken from 1996 to 2006 by Kimberlitic Searches Zimbabwe (Pvt) Ltd, the then Zimbabwe kimberlite exploration arm of De Beers, Zimbabwe, in their quest to find kimberlites, which were thought to be related to the Umkondo alluvial diamond deposit. As will be shown in the following chapters, many of the discovered kimberlites range from very low grade to non-diamondiferous, and are much younger than the Umkondo conglomerates, whose diamonds are in turn a great deal older. Thus the basic question concerning the origin or provenance of the Umkondo placer diamonds still remains unresolved. Because of the sheer size of the basin, modern, wide-area-coverage, geophysical exploration methods become appropriate to effectively generate diamond potential targets for further examination. This document will attempt to collate various data available to paint a true picture of the state of exploration within the Umkondo Basin.
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Goeie maniere en etiket
- Authors: Van Staden, Antoinique
- Date: 2016
- Language: Afrikaans , English
- Type: Thesis , Masters , MA
- Identifier: vital:6011 , http://hdl.handle.net/10962/d1021226
- Description: This bilingual collection of short stories combines the fairy tale form and the Bizarro genre to explore the value system ingrained in me at a very early age via my conservative Afrikaans upbringing. To my mind the four characteristics of the fairy tale form as identified by Kate Bernheimer (in her path-breaking essay “Fairy Tale is form, Form is Fairy Tale”) namely flatness, abstraction, intuitive logic and normalized magic, also apply to the Bizarro genre. This intersection is exemplified by some of Bernheimer's own fiction, as well as the fiction of Aimee Bender and Lucy Corin, among others, all of whom have influenced my writing. , Hierdie tweetalige versameling kortverhale kombineer sprokieselemente met die van die Bizarro-genre, om die waardesisteem wat van kleins af deur my konserwatiewe Afrikaanse opvoeding by my ingeprent is, te ondersoek. Die vier eienskappe van die sprokie word deur Kate Bernheimer in haar baanbrekende opstel Fairy tale is form, Form is fairy tale uitgelê as: ’n onbetrokke verteller, abstraksie, instinktiewe logika en genormaliseerde towerkuns. Na my mening is dié vier eienskappe ook op die Bizarro-genre van toepassing. Hierdie oorvleuling is sigbaar in Bernheimer se fiksie en ook onder andere Lucy Corin en Aimee Bender s'n – skrywers wat my werk beïnvloed het. , This thesis is presented in two parts: Afrikaans and English.
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Grace “The story of a wise cat and a cruel man.”
- Authors: Phepheng, Maruping
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:6005 , http://hdl.handle.net/10962/d1021213
- Description: Morgan, a widower and police detective, is quickly promoted from constable to captain after a series of successful criminal investigations, creating enemies in the process. One of the convicted and incarcerated is Paper, a gang leader with a violent upbringing. After a lucky release from prison, Paper, now Morgan’s fierce foe, plots to hurt him in the worst way possible – by killing his only son. The story is narrated by a cat named Grace, whose presence and companionship comes from another dimension and helps Morgan to keep sane.
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Gradient high performance liquid chromatographic method for the simultaneous analysis of efavirenz, emtricitabine and tenofovir
- Authors: Koekemoer, Sonya Mariana
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54679 , vital:26599
- Description: In 2014, approximately 6.8 million people in South Africa were HIV-positive, and the majority of those affected are aged 15 or older. A fixed-dose combination (FDC) antiretroviral (ARV) dosage form containing one non-nucleotide reverse transcriptase inhibitor (efavirenz) and two nucleotide reverse transcriptase inhibitors (emtricitabine and tenofovir) was licensed in South Africa in April 2013. New consolidated guidelines for HIV management and prevention of mother to child transmission (PMTCT) were published by the South African Department of Health in December 2014 and the FDC is now the recommended first-line treatment for HIV-positive patients. According to these guidelines all such people aged 15 and older, and weighing more than 40 kg, with a CD4 count of ≤ 500/ μl will be eligible for antiretroviral therapy (ART) using the FDC. In addition every pregnant and breastfeeding woman is eligible for lifelong ART regardless of CD4 count and EFV can be used as first-line treatment for pregnant women regardless of the length of gestation state of the pregnancy at that time. The use of this simplified regime is likely to promote much needed and improved adherence to therapy. An investigation into the development of a stability-indicating reversed-phase high performance liquid chromatography (RP-HPLC) method for the simultaneous quantitation of EFV, FTC and TNF was undertaken. Isocratic HPLC analysis was found to be unsuitable due to the highly polar FTC molecule eluting in the void. Therefore a gradient HPLC method was developed and validated. The method was validated according to the International Conference on Harmonisation, now known as International Council for Harmonization (ICH). Correlation coefficients > 0.999 were obtained for each assessment of linearity and FTC, TNF and EFV are linear in the range 0.4-40 μg/ml, 0.6-60 μg/ml and 1.2-120 μg/ml. The equation of the best-fit least squares regression lines for FTC, TNF and EFV were y = 0.0191x+0.0007, y = 0.0163x+0.0116 and y = 0.01x+0.016, respectively. The method is accurate as the y-intercept was < 2% of the detector response for all ARV, and the method is precise in terms of intra- and inter-assay precision as all % RSD < 2%. The stability-indicating nature of the method was demonstrated under acidic, alkaline and oxidative stress in addition to UV exposure and elevated temperatures, and the individual chromatograms were overlaid using Empower® 3 Software to establish whether there was interference with the peaks of interest. The forced degradation studies demonstrated the selectivity of the method for the ARV compounds. The method was applied to assay and in vitro dissolution studies of commercially available tablets. The amount of each active ingredient released from Atripla® was determined and compared to the amount of each drug released from Aspen Efavirenz® and Truvada® (a combination of FTC and TNF). The percent FTC released from Atripla® and Truvada® was similar based on the acceptance criteria for immediate-release BCS class 1 compounds. Statistical analysis was undertaken to compare the dissolution profiles of FTC, TNF and EFV. The percent of these compounds released in these studies indicate that bioequivalence testing would be required to declare these products interchangeable. The validated RP-HPLC and in vitro dissolution test method are suitable for routine quality control testing of solid oral dosage forms containing EFV, FTC and TNF, and as the dissolution method can discriminate between different formulations of the same molecule, these tools can also be used for analysis during formulation development studies. The method is not suitable for the analysis of the ARV plasma due to lack of sensitivity and an inability to quantitate the compounds at the required concentration levels. The use of HPLC with mass spectroscopy for quantitation would enhance the sensitivity of the method and may eliminate the quantitation of the molecules in the presence of interference that was observed when using UV detection. Fixed dose combination tablets are convenient for patient therapy and it is likely that in the future more molecules will be formulated into such dosage forms. However formulations such as these can pose significant difficulties when developing and using analytical methods for the quantitation of all compounds in the dosage form at the same time, in particular when the compounds have vastly different physico-chemical properties that impact the quality of a separation and therefore the analysis. Therefore when embarking on the development of FDC product cognisance of the difficulties of developing single methods for the analyses is required and approaches to overcome these difficulties should be considered.
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Hearing things
- Authors: Claassen, José
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:6019 , http://hdl.handle.net/10962/d1021243
- Description: William Carlos Williams wrote: "It isn't what the poet says that counts as a work of art, it's what he makes, with such intensity of purpose that it lives with an intrinsic movement of its own to verify its authenticity." I would like to think that my poems only borrow life from my pen, taking on an identity and music of their own with the help of some ‘making’ on my part. My poems embrace a continuum of human experience from the intrapersonal to the societal. Using imagistic and cinematic forms, they preserve the vitality of their sources, from the music of cityscapes, to the texture of emotions, to the narratives of particular characters.
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Historical perspectives and future directions for access to land, water and related ecosystem services in the Lower Sundays River Valley, South Africa: implications for human well being
- Authors: Chadzingwa, Karabo
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/442 , vital:19959
- Description: The legacy of South Africa’s history has facilitated unequal access to land and water resources. In the Lower Sundays River Valley (LSRV), a predominantly commercial farming area, differential access to land and water has impacted aspects of ecosystem service access and human well‐being for disenfranchised families over time. Despite the social, political and economic reform efforts in the past two decades, severe inertia towards efforts attempting to increase equitable access to land and water has been experienced. As a result, communities have mobilized and claimed their land from the government through the land restitution process. Based on a mixed‐methods approach, this research explores the ways in which access to land and water over time has influenced current levels of human well‐being among disenfranchised families. Provisioning and cultural ecosystem services were identified as key areas of loss as a result of forced evictions from land. Freedom of choice was a central and cross‐cutting theme regarding the ability to change levels of human well‐being. Although the loss of ecosystem services associated with land and water had an impact on households, the ecosystem services which are regarded as fundamental to human well‐being do not seem to have been lost. The study recommends the wide use of freedom of choice as an indicator for well‐being in the LSRV, as well as a consideration of subjective, objective and psychological measures of well‐being with regards to natural resources and ecosystem services access. Key agents in fostering desirable pathways toward equity and sustainability in the LSRV are identified with stakeholders as private businesses; inclusive governance; empowered and skilled individuals, as well as NGOs.
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How do editors' attitudes and their perceptions of readers' interests combine with other factors to influence the publication of articles on the natural sciences in the Daily Dispatch?
- Authors: Lang, Steven
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3893 , vital:20553
- Description: This half-thesis examines how editorial values and perceptions determine the quantity and nature of science articles published in the Daily Dispatch, a newspaper distributed through large parts of the Eastern Cape in South Africa. It was predicated on the notion that South African media in general does not cover the natural sciences adequately. In order to test this assumption I decided to investigate the production and publication of science content at the Daily Dispatch as a test case. This study‘s theoretical framework draws on the normative roles of the media in a democracy developed by Christians et al. (2009) and the models of science journalism described by Secko et al. (2012) to demonstrate how two parallel conceptions of democracy set diverse journalistic objectives and engender different types of science content. Having applied an essentially political framework, this thesis uses the Hierarchy of Influences Model devised by Reese and Shoemaker‘s (2014) to explore how an array of forces acting inside and outside the news organisation can shape the publication of science articles. A quantitative content analysis is used to ascertain the number of science articles published in the first six months of 2014. It investigates which science fields received the most coverage, and how prominently the articles are positioned. As the Daily Dispatch does not have any staff dedicated to the science beat, the analysis finds out who produces the science articles that are published. The second phase of this research is a series of interviews with senior editorial staff members aimed at probing the editorial thought processes that determine when and whether specific science stories should be covered. The personal views and biases of the editorial leadership are pivotal to this research because although the newspaper commissioned surveys to determine readership preferences, there were no questions about the sciences. Senior reporters were adamant that they worked for a political newspaper and that as a significant proportion of their readership lived in socio-economically deprived circumstances, they were bound to give priority to articles aimed at improving the lot of their readers. The third phase is a qualitative content analysis of selected articles designed to reveal how science articles are constructed. The final element of this thesis, which ultimately provides an answer to the research question, draws together conclusions from the previous phases to demonstrate the linkage between editorial values and the production of science content.
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How do social and personal identity, sense of place, connectedness to nature and environmental understanding influence the implementation of collective, large-scale biodiversity stewardship initiatives in South Africa?
- Authors: Potts, Tracey Ann
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3663 , vital:20534
- Description: Biodiversity stewardship is a mechanism that is used to conserve high value biodiversity assets. Biodiversity stewardship programmes focus on areas that are under immediate threat from development or under medium to long term threat from degradation or transformation that will result in habitat loss. Biodiversity stewardship provides a solution to the resource crisis being faced by many state and provincial conservation agencies, NGO’s (Non-Governmental Organisations) and PBO’s (Public Benefit Organisations) in that it facilitates the declaration, and the subsequent improved conservation management, of private or communally owned land whilst still retaining the existing tenure. The rate of habitat loss can often be slowed, or even reversed, by proactively securing these areas and facilitating management decision-making with a focus on biodiversity outcomes without the capital investment required by the State to purchase the land. In return for conservation management actions, certain land-use restrictions and the associated opportunity costs, the State offers a suite of incentives and benefits that are, where possible, tailored to meet the needs of the landowner. Particular regions of South Africa lend themselves well to the development of biodiversity stewardship initiatives which are designed to secure ecological processes and ecosystems across a landscape or an ecological feature at scales of tens of thousands of hectares. When developing landscape level biodiversity stewardship initiatives, negotiations tend to be focussed on groups of landowners. This requires collaboration and the collective alignment of natural resource management decision-making and conservation actions amongst neighbours. Gaining a better understanding of how the social constructs of ecological understanding, place attachment, connectedness to nature, occupational identity and social and personal identity influence decision-making, behaviour and group structure is a critically important factor when developing a tool to predict the likelihood of landowners to collectively commit to long-term, legally binding biodiversity stewardship programmes. The overarching hypothesis was that the social constructs listed above influence group dynamics within the context of collective pro-conservation behaviour. Social dynamics associated with large-scale biodiversity stewardship initiatives become complex when multiple landowners are involved. Could social cohesion and group culture be influenced by aspects of identity and do these in turn develop into barriers or motivators to coordinated and sustained conservation efforts? Further influences on the successful implementation of landscape scale biodiversity stewardship initiatives could include ecological understanding, connectedness to nature and place attachment. Structured interviews were held with the landowners engaged in two separate large-scale biodiversity stewardship sites, the Compassberg Protected Environment and the Baviaanskloof Hartland, in the Eastern Cape Province of South Africa. The interviews were followed up with surveys containing psychometric scales related to the influence of ecological understanding, place attachment, connectedness to nature and aspects of identity on commitment to collective long-term, large-scale biodiversity stewardship initiatives. The results from a set of non-parametric (exact) Wilcoxon rank-sum tests showed that scores on the new ecological paradigm scale and the place attachment scale latent variables were significantly different at the two study sites, at the 10% level of significance. Demographic differences between the two study sites influenced group dynamics, collective decision-making and commitment. The relationship between the latent variables (the five psychometric scales measured) and the ancillary variables (the demographic data describing the respondents) cannot be considered conclusive; however they do provide relatively useful insights into the development of a scale or tool to measure conservation opportunity. The thesis concludes with a proposed conservation opportunity assessment tool that can be utilised alongside the existing, well refined, conservation priority assessment tools to assist in decision-making when planning large, landscape scale biodiversity stewardship initiatives in South Africa.
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Hungry on arrival
- Authors: Mofokeng, Kabelo
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:6020 , http://hdl.handle.net/10962/d1021244
- Description: My collection embraces different kinds of poetry, I also write my own journey through my home in Pimville Soweto, the urban sounds and multilingual speech patterns as I move through it. Other poems draw on the Sesotho culture and tradition which still runs strongly in my family, and here I integrate the different kinds of sounds and associations of Sesotho and English in the same poem. I am inspired by the works and lives of artists and poets such as, Mafika Gwala, Jackson Hlungwani, and Herbie Tsoaeli amongst others. Other poems emerging are dense and self-reflective manifesting a transitional period whereby the poet experiments with form and style in the manner of Arthur Nortje and Angifi Dladla.
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I have gone away many times
- Authors: Metileni, Moses Nzama Khaizen
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:6010 , http://hdl.handle.net/10962/d1021225
- Description: I search for beauty and for myself amidst the debris and ruin and violence, so my poems are mainly grounded narratives that combine the lyrical and the political, celebration and lament. They reconnect with nature, the now ravaged landscapes that gave me my first impulse to make songs, poetry, and art. My poems also draw on my Xitsonga culture – its folklore, proverbs, idioms, parables, and clan praise songs. Stylistically I am influenced by Mahmoud Darwish’s and Garcia Lorca’s musical structures, while Aimé Césaire has shown me how to write a long poem in both abstract and concrete registers, and Yehuda Amichai how to write with a questioning style, dislodging accepted dogma. Local influences are Mzi Mahola and James Magaisa, with their critique and celebration of culture. I pick up fragments elsewhere, as I go.
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Ideas of poetic form: aspects of the Romantic-Symbolist tradition
- Authors: Oldert, David
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/54554 , vital:26587
- Description: The subject of the work is some of the formal and technical developments of modern poetry in the Romantic-Symbolist tradition. These developments were stimulated partly by the ideas of the non-intellectual Symbol inherited from the Romantics and the idea that poetry could be a musical medium inherited from some of the French Symbolists. Their combined influence led to a number of technical problems in the structuring of imagery and the handling of syntax. The work begins, therefore, by tracing the philosophical assumptions behind the ideas of the Symbol and of the musical analogy. I then go on to examine two of the difficulties that these ideas produced. One is the tension between the analogical structure of a poem’s imagery and its metaphorical texture: quite simply, the more compressed and complex a poet’s metaphors become, the more they tend to disrupt the poem’s structure of imagery. The other problem is obscurity, which is caused by insufficient objectification of private images in a symbolic structure, and by fused metaphor, which is essentially a metaphor with an obscured ground of resemblance. Finally, I show how these difficulties were solved by poets outside the tradition who used a more articulate kind of syntax, yet who also managed to combine that syntax with the ideal of symbolic form. The implicit argument, then, is that the Romantic-Symbolist ideas of form, and the New Critics’ theories of form which were largely based on them, are able to elucidate an essentially different kind of poetry, and thus have some degree of truth and use beyond the tradition that generated them.
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Identification of potential novel roles for Hsp70/Hsp90 organising protein (Hop) using proteomic analysis in human cells
- Authors: Wingate, Ianthe
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64758 , vital:28598
- Description: Expected release date-May 2018
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If I still want to breathe
- Authors: Billie, Ayanda
- Date: 2016
- Language: English , Xhosa
- Type: Thesis , Masters , MA
- Identifier: vital:6012 , http://hdl.handle.net/10962/1021231
- Description: One theme of this collection is the joy and the deep seated grief of my community of Kwa-Nobuhle; the brightness of hope on the faces on children running around our streets, the strides made by their mothers, the confusion of factory workers who are lost in darkness since the dawn of new dispensation. Then there are more personal poems: my own joys as well as the difficulties that have kept me from sleep and strangled my dreams as a writer, even though like Mafika Gwala, I believe that “words are born the way mothers beget children/words are born to survive time”. My style is influenced by imagistic, mystic and soulful poetry, such as the haunting Spanish voice of Garcia Lorca who wrote “I lose myself in the heart of certain children” and the absorbing isiXhosa voice of S E K Mqhayi. In response to their poetry my offering will be words that enliven us; my style will be what I see in the mirror, through the window, the sound of rain on my zinc roof and what frightens me. , Ndixomoloze ndiboph’ amaxonya, ndisenza eli linge lokuzama ukuxhathalaza kulo msinga uzakutshayela ulwimi lwethu. Nantso ke incwadana ndiyithe qhiwu ngendebe endiyithiye ngegama elithi Umhlaba Umanzi. Umhlaba umanzi ziinyembezi zabalilayo, umanzi kukubila kwabasebenzi besombha eludakeni, ufumile ziinkathazo zeminyaka zesizukulwana sesizukulwana. Injongo endifuna ukuyifezekisa ngeli nqaku yeyokuba umntu achole ntwana ithile ngokujonga imeko esiphila kuzo gabalala, ekuhlaleni, emakhayeni ethu nakwii ndawo esixelenga kuzo. Mhlawumbi kuyakuvuseleleka iingcinga neenkumbulo zamhla-mnene, okanye ibophe nezilonda ezimanzi. Ukwanda kwaliwa ngumthakathi. . . Nangomso. , This thesis is presented in two parts: English and isiXhosa.
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Impact of sectoral determinations in previously unregulated sectors: a case study of domestic work in Grahamstown
- Authors: Nxokweni, Saphokazi
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/3761 , vital:20542
- Description: Domestic labour is widely recognized as one of the most vulnerable labour sectors, both nationally and internationally. In South Africa, sectoral determination 7 was specifically developed to protect domestic workers’ rights and provide them with the means to negotiate with and hold employers to account. However, research over the past years has demonstrated that, while some areas of domestic labour have improved, many workers are still locked in exploitative labour relationships. This research shows that it may seem as if there are significant changes in this sector since the introduction of the sectoral determination, but paternalistic orientations, one-of-the-family myths, and food distribution suggest otherwise. The research concluded that continuities of exploitative and discriminatory practices are still prominent in the employment relationship when viewed through the lens of paternalistic care, food distribution, and the ‘one-of-the-family’ myth.
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Improved singlet oxygen generation by a novel bodipy dye and a study of upconverison nanoparticles mixed with a functionalized bodipy compound
- Authors: Wildervanck, Martijn Johannes
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3718 , vital:20538
- Description: This research explores the use of the versatile 4,4-difluoro-4-boro-3a,4a-diaza-s-indacene (BODIPY) dyes and the modification of their spectroscopic properties. The synthesis of a tetramethyl-BODIPY bearing a sterically hindered meso-phenyl ring with an ethynyl functional group at the para-position was compared to that of its freely rotating counterpart with no methyl substituents on the BODIPY core, with the fluorescence properties in particular proving to be markedly different. These phenyl-ethynyl-substituted BODIPYs were used as the starting materials for the synthesis of novel BODIPY dyes for sensor applications via Sonogashira coupling reactions at the ethynyl position, but this resulted instead in the serendipitous synthesis of a novel BODIPY dimer in which the para-positions of the meso-phenyl rings are linked by a diethynyl bridge. Following iodination at the 2, 6-positions, the dimer was found to have a singlet oxygen quantum yield of 0.88, compared to the value of 0.86 that was obtained for the analogous monomer. Since the εmax values for the main spectral bands of the dimers are significantly higher, the compounds may be of interest for singlet oxygen generation applications. A second study was carried out on the interaction between methyl ester functionalized BODIPY dyes and upconversion nanoparticles (UCNPs) to explore the possible use of BODIPY-UCNP conjugates in biomedical applications. The singlet oxygen generation properties of the BODIPY were tested following iodination at the 2, 6-positions, a singlet oxygen quantum yield value of 0.86 was obtained. Three sets of oleate capped UCNPs were synthesized with different diameters and were rendered water dispersible with the addition of a silica shell. The necessary scaffolding for conjugation to the BODIPY was provided by amine groups following functionalization of this shell. All of the sets of oleate capped and silica coated UCNPs were characterized by transmission electron microscopy (TEM) and X-ray diffractometry (XRD) and their emission properties were studied upon excitation at 978 nm with a diode laser with a Picoquant Fluotime 300 spectrophotometer that enables the measurement of anti-Stokes emission. The potential utility of UCNP-BODIPY conjugates for singlet oxygen applications, such as PDT, was then assessed.
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In silico analysis of the effects of non-synonymous single nucleotide polymorphisms on the human macrophage migration inhibitory factor gene and their possible role in human African trypanosomiasis susceptibility
- Authors: Kimuda, Magambo Philip
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3047 , vital:20355
- Description: Human African trypanosomiasis (HAT) is a public health problem in sub-Saharan Africa, with approximately 10,000 cases being reported per year. The Macrophage Migration Inhibitory Factor (MIF) which is encoded by a functionally polymorphic gene is important in both innate andadaptive immune responses, and has been implicated in affecting the outcome and processes of several inflammatory conditions. A recent study in mice to that effect showed that MIF deficient and anti-MIF antibody treated mice showed lowered inflammatory responses, liver damage and anaemia than the wild type mice when experimentally challenged with Trypanosomes. These findings could mean that the transcript levels and/or polymorphisms in this gene can possibly affect individual risk to trypanosomiasis. This is especially of interest because there have been reports of spontaneous recovery i.e self-cure/resistance in some HAT cases in West Africa. Prior to this discovery the general paradigm was that trypanosomiasis is fatal if left untreated. The aim of this study was to gain insights into how human genetic variation in forms of nonsynonymous SNPs affects the MIF structure and function and possibly HAT susceptibility. NsSNPs in the mif gene were obtained from dbSNP. Through homology modeling, SNP prediction tools, protein interface analysis, alanine scanning, changes in free energy of folding, protein interactions calculator (PIC), and molecular dynamics simulations, SNP effects on the protein structure and function were studied. The study cohort comprised of human genome sequence data from 50 North Western Uganda Lugbara endemic individuals of whom 20 were cases (previous HAT patients) and 30 were controls (HAT free individuals). None of the 26 nsSNPs retrieved from dbSNP (July 2015) were present in the mif gene region in the study cohort. Out of the eight variants called in the mif coding region there was only one missense variant rs36065127 whose clinical significance is unknown. It was not possible to test for association of this variant with HAT due to its low global MAF that was less than 0.05. Alanine scanning provided a fast and computationally cheap means of quickly assessing nsSNPs of importance. NsSNPs that were interface residues were more likely to be hotspots (important in protein stability). Assessment of possible compensatory mutations using PIC analysis showed that some nsSNP sites were interacting with others, but this requires further experimentation. Analysis of changes in free energy using FOLDX was not enough to predict which nsSNPs would adversely affect protein structure, function and kinetics. The MD simulations were unfortunately too short to glean any meaningful inferences. This was the first genetic study carried out on the people of Lugbara ethnicity from North Western Uganda.
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Industrial policy, institutions and industrial financing in South Africa: the role of the IDC and DBSA, and lessons from Brazil’s BNDES
- Authors: Fumbata, Nandipha
- Date: 2016
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1132 , http://hdl.handle.net/10962/d1021278
- Description: Institutions, particularly development finance institutions (DFIs) have been instrumental in economic development and the implementation of industrial policy throughout history. In 2007, the South African government identified the country’s DFIs as key to the implementation of its new industrial policy framework with the main objective of job creation. This thesis examines the impact that South Africa’s DFIs, particularly the IDC and the DBSA, have had on employment creation from 2010 to 2014. A comparative institutional approach is adopted in a case study analysis examining the role of the state in industrial financing. The financing activities of Brazil’s BNDES are explored by comparison to determine if there are possible lessons for South Africa. An analysis of the DFIs’ financial and annual reports and government policy documents is conducted. The political settlements framework is used as a basis for understanding the balance of power within the country and the impact this has had on the country’s industrial policy and industrial finance. The thesis finds that the financing activities of South Africa’s DFIs, particularly the IDC, have been directed at large scale capital intensive projects, with a large portion of disbursements channelled towards mining and mineral beneficiation. These sectors have also facilitated the most number of jobs. Even though the activities of the country’s DFIs are consistent with South Africa’s industrial policy and have facilitated job creation, it is evident that these efforts have not been on a scale that is large enough to reduce unemployment. Despite the DFIs’ efforts, there has been an increase in the number of unemployed South Africans between 2010 and 2014.
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Inequality in South Africa: a possible solution within the labour market
- Authors: Ferreira, John-Edward
- Date: 2016
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/4047 , vital:20594
- Description: This study sets out to identify the most effective way in which persistently and unacceptably high levels of inequality can be reduced in South Africa. Three alternative approaches were identified from the literature and their impact explored statistically. They are: the introduction of a ‘Social Solidarity Grant’; a decrease in unemployment by 5%; and a narrowing of the skill premium through an expansion of tertiary education. It is important to note that the study makes no attempt at explaining how these outcomes might be implemented or achieved. Rather, it sets out to determine only the effect that such policies may have on measured inequality. It was found that while the introduction of a new grant had a significant effect on inequality, this effect however, was once-off. The grant would be financed by individuals in the top decile through tax increases, which would be a complicated endeavour. Both job creation and a narrowing of the skills premium were significantly effective in decreasing inequality. The narrowing of the skills premium showed more promise due to its accelerating effectiveness in decreasing inequality over time and the fact that it directly addresses the problem of wage differentials. It was noted that the extreme levels of poverty and unemployment in South Africa may dampen enthusiasm for policies that narrow the skills premium to reduce inequality. These characteristics make job creation a more popular policy option because of the positive impact on poverty and unemployment as well as on inequality.
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Information security concerns around enterprise bring your own device adoption in South African higher education institutions
- Authors: Sauls, Gershwin Ashton
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3619 , vital:20530
- Description: The research carried out in this thesis is an investigation into the information security concerns around the use of personally-owned mobile devices within South African universities. This concept, which is more commonly known as Bring Your Own Device or BYOD has raised many data loss concerns for organizational IT Departments across various industries worldwide. Universities as institutions are designed to facilitate research and learning and as such, have a strong culture toward the sharing of information which complicates management of these data loss concerns even further. As such, the objectives of the research were to determine the acceptance levels of BYOD within South African universities in relation to the perceived security risks. Thereafter, an investigation into which security practices, if any, that South African universities are using to minimize the information security concerns was carried out by means of a targeted online questionnaire. An extensive literature review was first carried out to evaluate the motivation for the research and to assess advantages of using Smartphone and Tablet PC’s for work related purposes. Thereafter, to determine security concerns, other surveys and related work was consulted to determine the relevant questions needed by the online questionnaire. The quantity of comprehensive academic studies concerning the security aspects of BYOD within organizations was very limited and because of this reason, the research took on a highly exploratory design. Finally, the research deliberated on the results of the online questionnaire and concluded with a strategy for the implementation of a mobile device security strategy for using personally-owned devices in a work-related environment.
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Internal fingerprint extraction
- Authors: Darlow, Luke Nicholas
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/2959 , vital:20347
- Description: Fingerprints are a non-invasive biometric that possess significant advantages. However, they are subject to surface erosion and damage; distortion upon scanning; and are vulnerable to fingerprint spoofing. The internal fingerprint exists as the undulations of the papillary junction - an intermediary layer of skin - and provides a solution to these disadvantages. Optical coherence tomography is used to capture the internal fingerprint. A depth profile of the papillary junction throughout the OCT scans is first constructed using fuzzy c-means clustering and a fine-tuning procedure. This information is then used to define localised regions over which to average pixels for the resultant internal fingerprint. When compared to a ground-truth internal fingerprint zone, the internal fingerprint zone detected automatically is within the measured bounds of human error. With a mean- squared-error of 21.3 and structural similarity of 96.4%, the internal fingerprint zone was successfully found and described. The extracted fingerprints exceed their surface counterparts with respect to orientation certainty and NFIQ scores (both of which are respected fingerprint quality assessment criteria). Internal to surface fingerprint correspondence and internal fingerprint cross correspondence were also measured. A larger scanned region is shown to be advantageous as internal fingerprints extracted from these scans have good surface correspondence (75% had at least one true match with a surface counterpart). It is also evidenced that internal fingerprints can constitute a fingerprint database. 96% of the internal fingerprints extracted had at least one corresponding match with another internal fingerprint. When compared to surface fingerprints cropped to match the internal fingerprints’ representative area and locality, the internal fingerprints outperformed these cropped surface counterparts. The internal fingerprint is an attractive biometric solution. This research develops a novel approach to extracting the internal fingerprint and is an asset to the further development of technologies surrounding fingerprint extraction from OCT scans. No earlier work has extracted or tested the internal fingerprint to the degree that this research has.
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