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Blue ring of fire

  • Authors: O’Flaherty, Craig
  • Date: 2018
  • Subjects: Creative writing (Higher education) -- South Africa , South African poetry (English) -- 21st century
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/63615 , vital:28448
  • Description: My poems are reflections of shape, colour and emotions expressed through imagery. Their unsentimental landscape-realism echo my own feelings as well as broader human dimensions of contradiction and uncertainty, without trying to resolve them. In the same way that photography is the art of 'painting with light', my poems seek a language that evokes light and darkness. They aspire to what Keats said when writing about ‘negative capability’: “Poetical character has no self, it is anything and nothing, it has no character and enjoys light and shade”. My poems explore what I have learned about form – how line-length, syntax and musicality can add grace and energy to language. Poets that have influenced me include the classical Chinese poets such as Du Fu and Li Po, and the Generation of 27 Spanish poets, such as Antonio Machado and Leon Felipe.
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BODIPY dyes for singlet oxygen and optical limiting applications

  • Authors: Harris, Jessica
  • Date: 2018
  • Subjects: Photosensitizing compounds , Active oxygen -- Physiological effect , Photochemotherapy , Cancer -- Treatment , Nonlinear optics , BODIPY (Boron-dipyrromethene)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/58002 , vital:27014
  • Description: A series of structurally related BODIPY dyes were synthesised and characterised. Their photophysical properties were studied in order to determine whether they would be suitable candidates for use as photosensitisers in the photodynamic therapy (PDT) treatment of cancer. The synthesis of two highly fluorescent BODIPY cores was achieved via the acid-catalysed condensation of a pyrrole and a functionalised aldehyde. In order to promote intersystem crossing, and hence improve the singlet oxygen generation of these dyes, bromine atoms were added at the 2,6-positions of the BODIPY core. These dibrominated analogues showed good singlet oxygen quantum yields, and excellent photostability in ethanol. In order to red-shift the main spectral bands of the BODIPY dyes towards the therapeutic window, vinyl/ styryl groups were introduced at the 3-, 5-, and 7-positions via a modified Knoevengal condensation reaction. The addition of vinyl/ styryl groups to the BODIPY core caused an increase in fluorescence quantum yield as well as a decrease in singlet oxygen quantum yield with respect to the dibrominated analogues. However, two of the red-shifted BODIPY dyes still showed moderate singlet oxygen quantum yields. The use of BODIPY dyes in nonlinear optics (NLO) was explored. The nonlinear optical characterisations and optical limiting properties of a series of 3,5-dithienylenevinylene BODIPY dyes were studied, both in dimethylformamide (DMF) solution and when embedded in poly(bisphenol A carbonate) (PBC) as thin films. The 3,5-dithienylenevinylene BODIPY dyes showed typical nonlinear absorption behaviour, with reverse saturable absorption (RSA) profiles, indicating that they have potential as optical limiters. The second-order hyperpolarizability (Y), and third-order nonlinear susceptibility (/m[/(3)]) values are also reported for these dyes. The optical limiting values of one of the BODIPY dyes in solution, and two of the BODIPY-embedded PBC films, were below the maximum threshold of 0.95 J-cm-2. The effect of addition of substituents on the electronic structure of the BODIPY dyes was investigated using TD-DFT calculations. The calculated trends closely followed those determined experimentally.
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Bringing us back

  • Authors: Dhliwayo, Mercy
  • Date: 2018
  • Subjects: South African fiction (English) -- 21st century , Short stories, South African (English) -- 21st century
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/63077 , vital:28361
  • Description: My thesis takes the form of a collection of short stories set mostly in Zimbabwe and South Africa under the current political, social and economic climate. The themes I explore include forced migrations, identity, family disintegration and destitution. I use non-linear narration inspired by my reading of Dambudzo Marechera and Lidia Yuknavitch’s use of photographic imagery, in Black Sunlight and The Small Backs of Children respectively, to heighten my thematic concerns. The poetry in their language also serves as a source of inspiration, as does the graphic imagery used by Ayi Kwei Armah. In addition, I draw on the fragmented form used by Deepak Unnikrishnan to explore migration in his collection, Temporary People and Miljenko Jergovic’s investigation of violence and displacement in Sarajevo Marlboro.
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Challenging Biblical boundaries: Jeanette Winterson’s postmodern feminist subversion of Biblical discourse in Oranges are not the only fruit (1985) and Boating for beginners (1985)

  • Authors: Erasmus, Shirley
  • Date: 2018
  • Subjects: Winterson, Jeanette, 1959- -- Criticism and interpretation , Bible -- Feminist criticism , Bible -- Criticism, interpretation, etc , Postmodernism -- Religious aspects , Winterson, Jeanette, 1959- -- Oranges are not the only fruit , Winterson, Jeanette, 1959- -- Boating for beginners , Patriarchy in literature , Sex discrimination in literature
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/59121 , vital:27430
  • Description: This thesis investigates the subversion of Biblical discourse in Jeanette Winterson’s first two novels, Oranges are Not the Only Fruit and Boating for Beginners. By rewriting Biblical stories Winterson challenges traditional Western religious discourses and their rules for heteronormative social and sexual behaviours and desires. Winterson’s texts respond to the patriarchal nature of socially pervasive texts, such as the Bible, by encouraging her readers to regard these texts with suspicion, thus highlighting what can be seen as a ‘postmodern concern’ with the notion of ‘truth’. Chapter One of this thesis comprises a discussion of Biblical boundaries. These boundaries, I argue, are a process of historical oppression which serves to subjugate and control women, a practice inherent in the Bible and modern society. The Biblical boundaries within which women are expected to live, are carefully portrayed in Oranges and then comically and blasphemously mocked in Boating. Chapter One also argues that Winterson’s sexuality plays an important role in the understanding of her texts, despite her desire for her sexuality to remain ‘outside’ her writing. Chapter Two of this thesis, examines the mix of fact and fiction in Oranges, in order to create a new genre: fictional memoir. The chapter introduces the concept of the ‘autobiographical pact’ and the textual agreement which Winterson creates with her readers. In this chapter, I examine Winterson’s powerful subversion of Biblical discourse, through her narration of Jeanette’s ‘coming out’ within a Biblical framework. Chapter Three of this thesis examines Winterson’s second book, Boating, and the serious elements of this comic book. This chapter studies the various postmodern narrative techniques used in Boating in order to subvert Biblical and historical discourse. Chapter Three highlights Winterson’s postmodern concern with the construction of history as ‘truth’. Finally, Chapter Four compares Oranges and Boating, showing the texts as differing, yet equally relevant textual counterparts. This chapter examines the anti-feminine characters in both texts and Winterson’s ability to align her reader with a feminist or lesbian viewpoint. This thesis argues that Winterson’s first two texts deliberately challenge Biblical discourse in favour of a postmodern feminist viewpoint.
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Characterisation of surfaces modified with phthalocyanines through click chemistry for applications in electrochemical sensing

  • Authors: O'Donoghue, Charles St John Nqwabuko
  • Date: 2018
  • Subjects: Electrodes, Carbon , Phthalocyanines , X-ray photoelectron spectroscopy , Electrochemistry , Electrochemical sensors , Hydrazine , Click chemistry
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/58046 , vital:27038
  • Description: One form of surface modification was primarily investigated in this work on glassy carbon electrodes. The form of modification is comprised of a series of steps in which electrografting is first applied to the glassy carbon surface, which is then followed up with click chemistry to ultimately immobilise a phthalocyanine onto the surface. The modified glassy carbon electrodes and surfaces were characterised with a combination of scanning electrochemical microscopy, X-ray photoelectron spectroscopy and various electrochemical methods. In this work, three alkyne substituted phthalocyanines were used. Two novel phthalocyanines, with nickel and cobalt metal centres, were studied alongside a manganese phthalocyanine reported in literature. Each of the three phthalocyanines was modified at the peripheral position with a 1-hexyne group, via a glycosidic bond, yielding the terminal alkyne groups that were used for subsequent click reactions. In situ diazotisation was used to graft 4-azidoaniline groups to the surface of the glassy carbon electrode. The azide bearing 4- azidoaniline groups were thus used to anchor the tetra substituted phthalocyanines to the surface of the electrodes. This method yielded successful modification of the electrodes and lead to their application in sensing studies. The modified electrodes were primarily used to catalyse the common agricultural oxidising agent hydrazine.
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Chasing shadow and make believe

  • Authors: Mofokeng, Reikanne
  • Date: 2018
  • Subjects: Creative writing (Higher education) -- South Africa , South African fiction (English) -- 21st century , Science fiction, South African (English) -- 21st century
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/63626 , vital:28449
  • Description: My thesis is a science fiction novella. It follows the story of an adolescent boy, Shadow, and a little girl, Makebelieve, in an ahistorical future. The world that they traverse is earth, after being nursed back to health, by technologically advanced Southern African societies. A series of inexplicable astronomical events leads to their being hunted down. Through the travels of Shadow and Makebelieve I show how the world and the societies around them operate. I am inspired by Samuel R Delaney’s Aye, Gomorrah and Derrick Bell’s The Space Traders, because of their prowess in world building and exploration of complex and innovative ideas.
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Chemical weathering on selected nunataks in western Dronning Maud Land, Antarctica

  • Authors: Knox, Jenna Tracy
  • Date: 2018
  • Subjects: Glacial climates -- Antarctica -- Queen Maud Land , Glaciology -- Antarctica -- Queen Maud Land , Chemical weathering -- Antarctica -- Queen Maud Land , Atmospheric carbon dioxide -- Environmental aspects , Climatic changes -- Antarctica -- Queen Maud Land , Nunataks -- Antarctica -- Queen Maud Land
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/61658 , vital:28046
  • Description: High latitude areas are sensitive to the impacts of climate change, and it is expected that the impact of greenhouse warming will be much higher in the polar regions than in any other climatic zones, with the most highly affected area being that of the Antarctic rim (Barsch, 1993). Weathering and pedogenic processes respond to variations in climate, with models predicting that chemical weathering may increase synchronously with global carbon dioxide levels increase, due to dissolution rates and the erosional impact of hydrological cycles in warming climates (Anderson & Anderson, 2010). As liquid water becomes more available in Antarctica the potential for chemical weathering, due to a less moisture-limited environment and increased temperatures, increases (Convey et al., 2009). Weathering processes are important for soil formation and the production of fine-grained material, with chemical weathering being an active constituent of this. Increased rates of soil formation are likely to occur, with global climate changes resulting in greater chemical weathering occurring in Antarctica. Opportunistic sampling was conducted during the Austral summer of 2016/2017, whereby rock, snow and meltwater samples were taken at various sites within the western portion of Dronning Maud Land of Antarctica. Rock samples were placed in resin, and cut with a diamond saw to create thin sections. Optical microscopy and scanning transmission electron microscopy (STEM) were used to analyse mineral weight percentage with depth. Twelve soil samples were dried and weighed, sieved and statistically represented according to particle size. Inductively coupled plasma mass spectrometry (ICP-MS) determined the geochemical analysis for 10 water and snow samples. Rock hardness was inferred through the use of an Equotip, with rebound values recorded for multiple rock faces and samples. Thermal regimes of rock temperature was further recorded using a FLIR infrared camera, and documented for each rock face over a 24 hour period at 2 hourly intervals. The products of increased chemical weathering were evident from particle size analysis; samples were very poorly sorted in nature, and undergo in situ weathering, whereby products were not removed by erosional processes. Weathering rinds were found to be siliceous and ferric, depending on parent lithology. Ferric ratios increased in wt.% from the substrate rock to the external surface, creating the red, iron rich crusts noted on the hand specimens. The observable chemical weathering was found adjacent to intrusions through Precambrian dolerites. Geochemical analysis revealed thin, carbonaceous features, with impurity-rich layers, characteristic of speleothem formation. Carbonaceous layers did not follow underlying substrate features, rather deposited at the external surface, upon which, further precipitation growth could occur, creating karst features. Extensive gypsum coatings (>2mm) under BSE imagery were identified, with the abundance of gypsum salts (below surface level) and rock coatings indicating active sulphuric acid weathering, in western Dronning Maud Land, Antarctica. Were mechanical processes faster than chemical, weathering rinds and solution features on silicate rocks would be uncommon in the Antarctic, periglacial landscape. However, this is not the case as the existence of these landforms implies that chemical weathering may occur faster than mechanical weathering processes (Pope et al., 1995). In a changing world, one needs to monitor these processes at a micro-scale in order to fully understand how periglacial environments react to global climatic changes, and the subsequent impacts on these sensitive environments.
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Citizen science, treatment and microbial compliance monitoring in rainwater harvesting in Namibia

  • Authors: Angala, Hallo Angaleni Nameya
  • Date: 2018
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/62082 , vital:28105
  • Description: Expected release date-April 2020
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Constructing an EMF radiation Hygeia framework and model to demonstrate a public interest override

  • Authors: Lech, James Chrystopher
  • Date: 2018
  • Subjects: Electromagnetic fields , Electromagnetic fields -- Health aspects , Electromagnetic fields -- Measurement , Public interest , Radiation -- Measurement , HYGEIA , Promotion of Access to Information Act (PAIA)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/58695 , vital:27364
  • Description: Scientific views on EMF radiation dosimetry and models increasingly suggest that even a tiny increase in the incidence of diseases resulting from exposure to EMF radiation could have broad¹ implications for public health, social accounting and the economy. In South Africa (SA) there is no national EMF radiation exposure protection standard, statutory monitoring or regulations. Multinational High Court deliberations indicate the need for public interest EMF radiation exposure protection standards in South Africa. Domestic citizens, academics, as well as regulatory and legislative practitioners, are unable to effectively monitor and investigate EMF radiation exposure emissions from infrastructure sources, because industries refuse to provide the required data. Industries have, since 2003, continually obstructed access to the data and the establishment of a national EMF radiation standard, citing that it would be in conflict with their strategic economic interests. The demonstration of a public interest override (PIO) function is legislatively required to gain access to the required data. This study constructed (1) a framework and (2) a model to perform test simulations against the (3) PIO criteria to demonstrate a PIO function and tested one PIO simulation scenario. Testing the PIO scenario firstly required the construction of a public interest framework, drawing input from multiple disciplines. The framework literature review used systematic case law and scientific-technical analysis whilst the framework science sought to understand the connections, feedbacks, and trajectories that occur as a result of natural and human system processes and exchanges. The EMF radiation exposure system functions to support human wellbeing needs and to explore the benefits and losses associated with alternative futures with the goal to uncover the current and future limits thereof. In the second instance a HYGEIA² model was selected as a base investigation and forecast simulation tool. The study had to uncover the key attributes and parameters necessary to construct and to run successful EMF radiation exposure simulations. Thereafter the HYGEIA model was modified to specifically identify and evaluate EMF radiation exposure hazard conditions. Through subsequent simulation runs, the constructed framework was then tested. Requested anthroposphere information was synthesized within a systems model to forecast ecosystem services and human-use dynamics under alternative scenarios. The simulation used the model, the model references and the framework for guidelines, thus allowing multiple simulation / demonstration runs for different contexts or scenarios. The third step was the construction of a PIO checklist which guides criteria testing and provides a means of gaining pertinent information for further studies, based on this dissertation. Framework EMF radiation policy inputs into the model were intersected with identified vulnerable area facilities which were selected based on international criteria. The research output revealed potential EMF radiation violations which served as system feedback inputs in support of a demonstrated PIO function. The research recommends that the identified EMF radiation exposure violations of public health undergo a Promotion of Access to Information Act (PAIA) judicial review process to confirm the research findings. The judicial qualification of a PAIA PIO function of ‘substances released into the environment’ and ‘public safety or environmental risk’ would enable access to EMF radiation emissions data essential to future studies.
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Dangerous liaisons or critical alliances: student perceptions of community engagement at Rhodes University, South Africa

  • Authors: Levy, Simone Arielle
  • Date: 2018
  • Subjects: Rhodes University -- Students -- Public services , Community and college -- South Africa -- Eastern Cape , Education, Higher -- Social aspects -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/57411 , vital:26907
  • Description: Community Engagement (CE) in South Africa is an increasingly important feature of the relationship between the university and a broader community, and may aid in bridging the entrenched social divisions of this nation. This will only be possible if CE succeeds in uniting the knowledge production interests of the university and the broader community. Through CE, knowledge production and dissemination from within the university should be made more relevant and applicable because it is based on a relationship or engagement with a community. Based on the perceptions of student volunteers in a CE programme at a South African university, this thesis set out to ask whether or not students are transformed through university-community collaboration. This research examines the perceptions and motivations of student volunteers entering community partnership programmes. More importantly, it asks whether these engagements are merely a “weekend special” consisting of shallow engagements, which last only a few hours a week that provide institutional window dressing; or well-intended engagements through which students build meaningful relationships and experience learning opportunities that prepare them for real world civic participation. As this thesis focuses on the student perspective, it explores whether or not CE has an impact, both personally and educationally or academically, on the lives of individual student volunteers. The literature on CE argues that students’ participation in CE opportunities should enhance academic learning, personal growth and promote a sense of citizenship or civic responsibility. Based on the perceptions of a small group of student volunteers at one university, this thesis identifies possible successes and limitations of CE volunteering programmes in order to see if what is promoted in the literature or institutional policies is being experienced or achieved in practice at universities. I argue that students are indeed transformed through processes of CE, often in unexpected ways, and despite many difficulties. Therefore, if CE provides students with more holistic learning opportunities while attending universities for academic ends, it is important to look at in what ways this is achieved.
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De-identification of personal information for use in software testing to ensure compliance with the Protection of Personal Information Act

  • Authors: Mark, Stephen John
  • Date: 2018
  • Subjects: Data processing , Information technology -- Security measures , Computer security -- South Africa , Data protection -- Law and legislation -- South Africa , Data encryption (Computer science) , Python (Computer program language) , SQL (Computer program language) , Protection of Personal Information Act (POPI)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/63888 , vital:28503
  • Description: Encryption of Personally Identifiable Information stored in a Structured Query Language Database has been difficult for a long time. This is owing to block-cipher encryption algorithms changing the length and type of the input data when encrypted, which cannot subsequently be stored in the database without altering its structure. As the enactment of the South African Protection of Personal Information Act, No 4 of 2013 (POPI), was set in motion with the appointment of the Information Regulators Office in December 2016, South African companies are intensely focused on implementing compliance strategies and processes. The legislation, promulgated in 2013, encompasses the processing and storage of personally identifiable information (PII), ensuring that corporations act responsibly when collecting, storing and using individuals’ personal data. The Act comprises eight broad conditions that will become legislation once the new Information Regulator’s office is fully equipped to carry out their duties. POPI requires that individuals’ data should be kept confidential from all but those who specifically have permission to access the data. This means that not all members of IT teams should have access to the data unless it has been de-identified. This study tests an implementation of the Fixed Feistel 1 algorithm from the National Institute of Standards and Technology (NIST) “Special Publication 800-38G: Recommendation for Block Cipher Modes of Operation : Methods for Format-Preserving Encryption” using the LibFFX Python library. The Python scripting language was used for the experiments. The research shows that it is indeed possible to encrypt data in a Structured Query Language Database without changing the database schema using the new Format-Preserving encryption technique from NIST800-38G. Quality Assurance software testers can then run their full set of tests on the encrypted database. There is no reduction of encryption strength when using the FF1 encryption technique, compared to the underlying AES-128 encryption algorithm. It further shows that the utility of the data is not lost once it is encrypted.
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Demographic change in the Upper Tsitsa Catchment: the integration of census and land cover data for 2001 and 2011

  • Authors: Hodgson, Danuta Lorina
  • Date: 2018
  • Subjects: Land use -- South Africa -- Eastern Cape , Watersheds -- South Africa -- Eastern Cape , Thematic maps -- South Africa -- Eastern Cape , Population density -- South Africa -- Eastern Cape , Mzimvubu River Watershed (South Africa) -- Census , Upper Tsitsa Catchment (South Africa)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/57296 , vital:26870
  • Description: The purpose of this research was to determine if the integration of census and land cover data could provide evidence of spatial patterns and temporal change for the Upper Tsitsa Catchment. This thesis contributed to academic literature with regards to dasymetric mapping and provided a database for the Ntabelanga and Laleni Ecological Infrastructure Project. The study took place in the Upper Tsitsa Catchment which is located in the north-eastern region of the Eastern Cape and falls within the uMzimvubu Catchment. South Africa National Population Censuses for 2001 and 2011 and the National Land Cover data sets for 2000 and 2013/14 were used to create dasymetric maps depicting demographic changes over time for the catchment area. Spatial statistics were performed on the dasymetric and choropleth map to determine the accuracy of the data that was created. From the results, it was found that although the statistics were skewed, the method was more accurate in displaying the population densities, which was noted during the sampling process of the spatial analysis. It was found that there had been a decrease in the population density within the catchment. This affected the density of several other variables such as population race group, language and employment status statistics as decreases in these values could be due to individuals migrating out of the catchment as well as socio-economic upliftment, such as having better access to services. The use of dasymetric mapping allowed an accurate representation of the population density from the census data to be created. The results of the dasymetric mapping were more accurate as they depicted where the population within the enumeration areas were located, and recognised that some areas were populated while some areas were not. To conclude, it was found that using dasymetric mapping provided reliable and useful data about population density and enables comparison over time.
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Designing and prototyping WebRTC and IMS integration using open source tools

  • Authors: Motsumi, Tebagano Valerie
  • Date: 2018
  • Subjects: Internet Protocol multimedia subsystem , Session Initiation Protocol (Computer network protocol) , Computer software -- Development , Web Real-time Communications (WebRTC)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/63245 , vital:28386
  • Description: WebRTC, or Web Real-time Communications, is a collection of web standards that detail the mechanisms, architectures and protocols that work together to deliver real-time multimedia services to the web browser. It represents a significant shift from the historical approach of using browser plugins, which over time, have proven cumbersome and problematic. Furthermore, it adopts various Internet standards in areas such as identity management, peer-to-peer connectivity, data exchange and media encoding, to provide a system that is truly open and interoperable. Given that WebRTC enables the delivery of multimedia content to any Internet Protocol (IP)-enabled device capable of hosting a web browser, this technology could potentially be used and deployed over millions of smartphones, tablets and personal computers worldwide. This service and device convergence remains an important goal of telecommunication network operators who seek to enable it through a converged network that is based on the IP Multimedia Subsystem (IMS). IMS is an IP-based subsystem that sits at the core of a modern telecommunication network and acts as the main routing substrate for media services and applications such as those that WebRTC realises. The combination of WebRTC and IMS represents an attractive coupling, and as such, a protracted investigation could help to answer important questions around the technical challenges that are involved in their integration, and the merits of various design alternatives that present themselves. This thesis is the result of such an investigation and culminates in the presentation of a detailed architectural model that is validated with a prototypical implementation in an open source testbed. The model is built on six requirements which emerge from an analysis of the literature, including previous interventions in IMS networks and a key technical report on design alternatives. Furthermore, this thesis argues that the client architecture requires support for web-oriented signalling, identity and call handling techniques leading to a potential for IMS networks to natively support these techniques as operator networks continue to grow and develop. The proposed model advocates the use of SIP over WebSockets for signalling and DTLS-SRTP for media to enable one-to-one communication and can be extended through additional functions resulting in a modular architecture. The model was implemented using open source tools which were assembled to create an experimental network testbed, and tests were conducted demonstrating successful cross domain communications under various conditions. The thesis has a strong focus on enabling ordinary software developers to assemble a prototypical network such as the one that was assembled and aims to enable experimentation in application use cases for integrated environments.
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Developing a citizen technician based approach to suspended sediment monitoring in the Tsitsa River catchment, Eastern Cape, South Africa

  • Authors: Bannatyne, Laura Joan
  • Date: 2018
  • Subjects: Sediments (Geology) -- Management , Sediments (Geology) -- South Africa -- Eastern Cape , Watersheds -- South Africa -- Eastern Cape , Suspended sediments -- South Africa -- Eastern Cape , Suspended sediments -- Monitoring -- Citizen participation , Tsitsa River
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/62593 , vital:28211
  • Description: Suspended sediment (SS) in channels is spatiotemporally heterogeneous and, over the long term, is known to be moved predominantly by flood flows with return periods of ~1 - 1.5 years. Flood flows in the Tsitsa catchment (Eastern Cape Province, South Africa) are unpredictable, and display a wide range of discharges. Direct, flood-focused SS sampling at sub-catchment scale was required to provide a SS baseline against which to monitor the impact on SS of catchment rehabilitation interventions, to determine the relative contributions of sub-catchments to SS loads and yields at the site of the proposed Ntabelanga Dam wall, and to verify modelled SS baselines, loads and yields. Approaches to SS sampling relying on researcher presence and/or installed equipment to adequately monitor SS through flood flows were precluded by cost, and the physical and socioeconomic conditions in the project area. A citizen technician (CT)-based flood-focused approach to direct SS sampling was developed and implemented. It was assessed in terms of its efficiency and effectiveness, the proficiency of the laboratory analysis methods, and the accuracy of the resulting SS data. A basic laboratory protocol for SSC analysis was developed, but is not the focus of this thesis. Using basic sampling equipment and smartphone-based reporting protocols, local residents at eleven points on the Tsitsa River and its major tributaries were employed as CTs. They were paid to take water samples during daylight hours at sub-daily timestep, with the emphasis on sampling through flood flows. The method was innovative in that it opted for manual sampling against a global trend towards instrumentation. Whilst the management of CTs formed a significant project component, the CTs benefitted directly through remuneration and work experience opportunities. The sampling method was evaluated at four sites from December 2015 - May 2016. The CTs were found to have efficiently and effectively sampled SS through a range of water levels, particularly in the main Tsitsa channel. An acceptable level of proficiency and accuracy was achieved, and many flood events were successfully defined by multiple data points. The method was chiefly limited by the inability of CTs to sample overnight rises and peaks occurring as a result of afternoon thunderstorms, particularly in small tributaries. The laboratory process was responsible for some losses in proficiency and accuracy. Improved laboratory quality control was therefore recommended. The CT-based approach can be adapted to other spatial and temporal scales in other areas, and to other environmental monitoring applications.
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Developing and testing the congruency of selected biological indicators and an existing tool designed to assess wetland health in agricultural settings in the KZN Midlands

  • Authors: Kubheka, Patrick Skhumbuzo
  • Date: 2018
  • Subjects: Wetland conservation -- South Africa -- KwaZulu-Natal , Wetland management -- South Africa -- KwaZulu-Natal , Wetland ecology -- South Africa -- KwaZulu-Natal , Ecosystem services -- South Africa -- KwaZulu-Natal , Environmental monitoring -- South Africa -- KwaZulu-Natal , Water quality biological assessment -- South Africa -- KwaZulu-Natal
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/58310 , vital:27211
  • Description: Despite the fact that wetlands have been understood to be important for a wide range of ecosystem services, wetlands continue to be degraded globally. There has been a growing need to develop biomonitoring tools that reflect the present ecological state of wetlands, but very few attempts have been made in South Africa to achieve this, and those that have attempted this have generally achieved limited success. This study was conducted to develop and test the congruency of four selected biological indicators (dragonflies, frogs, macroinveterbrates and plants) in relation to the assessment of present ecological state using an existing method in South Africa, "WET-Health". WET-Health assessments rely primarily on transformations to a wetland that result from human impacts in both the catchment and the wetland itself. Using the tool, a health score is obtained that is consistent with the Department of Water Affairs (DWA) current "present ecological state” as applied to river health assessment. The study was conducted in agricultural settings of the Midlands of KwaZulu-Natal based on 13 wetlands. The selected wetlands were scored using WET - Health and grouped in four different ecological condition classes (A, B, C and D). Physical characteristics (wetland area, mean depth), biological characteristics (species cover/abundance, presence and species richness), and chemical characteristics (ammonia, pH, sulphate, nitrogen and phosphate) were also recorded in the selected wetlands. Nineteen different species of dragonfly were recorded in this study. The study demonstrated that dragonflies are a promising bioindicator of wetland present ecological state as the dragonfly index was found to be closely correlated with WET- Health scores. Open water bodies within the selected wetlands were the focus of dragonfly sampling, as male dragonflies are territorial and they will patrol or be found around this habitat. Emergent vegetation dominated by sedges formed the focus of macroinvertebrate sampling in this study because greater numbers of macroinvertebrate families were found in this biotope in comparison to open water areas with no emergent vegetation. A total of 47 macroinvertebrate families were recorded in this study, but SASS5 scores based on macroinvetebrates showed no correlation with WET-Health scores. A total of 10 different frog species were recorded in this study. All the species were common frog species found in most parts of the country. Frog species richness and occurrence showed no correlation with WET- Health scores. A total of twenty samples of two meter radius were measured per wetland and sampled for plant species and estimation of cover-abundance of each species per sample. Over 50 different plant species were recorded in this study, and both species accumulation and species richness showed a degree of correlation with WET-Health scores. All the wetlands in class A had generally higher species accumulation rate and species richness compared to the other wetland classes. In addition to testing the congruency of four selected biological indicators with WET- Health, water quality was measured in all the wetlands. Wetlands in class A were associated with improved water quality as the water passes through the wetland. However, wetlands in class C and D did not show consistently improved water quality between the apex and the toe of these wetlands. In some cases the water quality deteriorated as it passed through wetlands in these two classes.
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Developing leadership and learner voice: a formative intervention in a Learner Representative Council in a Namibian secondary school

  • Authors: Haipa, Vistorina
  • Date: 2018
  • Subjects: School management and organization -- Namibia , Educational leadership -- Namibia , Education, Secondary -- Namibia , Student government -- Namibia , Student participation in administration -- Namibia , Student participation in administration -- Law and legislation -- Namibia , Cultural Historical Activity Theory
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/62188 , vital:28136
  • Description: Learner participation in leadership in Namibian schools was legislated in 2001 through the Namibian Education Act, No. 16 of 2001. This has then become a requirement for all secondary schools to establish a Learner Representative Council (LRC). However, this legislation only gives mandates to schools with grade 8-12. Despite the impetus of having a LRC in secondary schools, learner leadership and voice remains limited, given that we are 26 years into our democracy. This awakened my interest to conduct a study aimed at developing leadership and voice within the LRC in a Namibian secondary school. Additionally, this study was conducted to contribute to filling the gap in literature of Cultural Historical Activity Theory (CHAT) studies in the field of Education Leadership and Management. In this critical case orientation, the LRC were the subjects and the object of the activity was voice and leadership development within the LRC. I investigated participants’ perspectives on LRC leadership opportunities that existed in the case study school as well as factors that enabled and constrained leadership and voice development within the LRC of Omukumo (pseudonym) Secondary School in the northern part of Namibia. My study adopted a formative intervention design, using qualitative methodologies such as document analysis, observation, interviews, questionnaires and Change Laboratory Workshops. This study was framed by the second generation of CHAT. CHAT in this study was used as a methodological and analytical tool to surface the contradictions. Additionally, data were analysed by means of constructing categories and themes. Five sets of findings emerged: (1) a lack of conceptual awareness of the construct ‘learner leadership’: learner leadership was understood in terms of the LRC, (2) LRC members were not really acknowledged as equal participants in the school decision-making due to unequal power relations between the teachers and the LRC members, (3) misinterpretation of LRC policy that speak about the establishment of learners club and inadequate LRC training hindered the development of voice and leadership within the LRC, (4) the overall leadership role assigned to the LRC was to oversee the adherence of the school rules, and last (5) learner leadership and voice was still developing in the case study school. My key recommendation based on the research findings is the need for on-going LRC training at regional level; a need for large scale comparative studies between two African countries (Namibia, & South Africa) on the topic of learner leadership development and last, a need for workshops to train teachers on the implementation of national policies in schools, in particular those that speak to issues of learner voice and leadership.
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Development and assessment of a smart thermosetting intranasal hydrogel for lamotrigine

  • Authors: Melamane, Siyabonga
  • Date: 2018
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/62975 , vital:28349
  • Description: Expected release date-April 2020
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Development and assessment of gastroretentive sustained release captopril micro-balloons

  • Authors: Oridota, Omoyosola Omolola
  • Date: 2018
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/63491 , vital:28419
  • Description: Expected release date-April 2020
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Development and evaluation of a web application employing artificial neural networks to facilitate the prediction of antiretroviral drug resistance in patients infected with HIV-1 subtype B

  • Authors: Nabatanzi, Margaret
  • Date: 2018
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/63396 , vital:28406
  • Description: Expected release date-April 2019
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Development and optimisation of a novel Plasmodium falciparum Hsp90-Hop interaction assay

  • Authors: Wambua, Lynn
  • Date: 2018
  • Subjects: Plasmodium falciparum , Molecular chaperones , Heat shock proteins , Protein-protein interactions , Antimalarials
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/62626 , vital:28216
  • Description: Protein-protein interactions are involved in a range of disease processes and thus have become the focus of many drug discovery programs. Widespread drug resistance to all currently used antimalarial drugs drives the search for alternative drug targets with novel mechanisms of action that offer new therapeutic options. Molecular chaperones such as heat shock proteins facilitate protein folding, play a role in protein trafficking and prevent protein misfolding in cells under stress. Heat shock protein 90 (Hsp90) is a well-studied chaperone that has been the focus of cancer drug development with moderate success. In Plasmodium falciparum (P. falciparum), heat shock proteins are thought to play a vital role in parasite survival of the physiologically diverse habitats of the parasite lifecycle and because Hsp90 is prominently expressed in P. falciparum, the chaperone is considered a potentially ideal drug target. Hsp90 function in cells is regulated by interactions with co-chaperones, which includes Heat shock protein 70-Heat shock protein 90 organising protein (Hop). As opposed to directly inhibiting Hsp90 activity, targeting Hsp90 interaction with Hop has recently been suggested as an alternative method of Hsp90 inhibition that has not been explored in P. falciparum. The aim of this research project was to demonstrate PfHsp90 and PfHop robustly interact in vitro and to facilitate high-throughput screening of PfHsp90-PfHop inhibitors by developing and optimising a novel plate capture Hsp90-Hop interaction assay. To establish the assay, the respective domains of the proteins that mediate Hsp90-Hop interaction were used (Hsp90 C- terminal domain and Hop TPR2A domain). The human Hsp90 C-terminal domain and glutathione-S-transferase (GST) coding sequences were cloned into pET-28a(+) and murine and P. falciparum TPR2A sequences into pGEX-4T-1 plasmids to enable expression of histidine-tagged and GST fusion proteins, respectively, in Escherichia coli. The P. falciparum Hsp90 C-terminal domain sequence cloned into pET-28a(+) was supplied by GenScript. The constructs were transformed into T7 Express lysYcompetent E. coli cells and subsequent small- scale expression studies showed the recombinant proteins were expressed in a soluble form allowing for subsequent protein purification. Purification of the recombinant proteins was achieved using nickel-NTA and glutathione affinity chromatography for the His-tagged (Hsp90 C-terminal domains and GST) and GST fusion proteins (TPR2A domains), respectively. The purified proteins were used to establish and optimise mammalian and P. falciparum Hsp90- Hop interaction assays on nickel-coated plates by immobilising the His-tagged C-terminal domains on the plates and detecting the binding of the GST-TPR2A domains using a colorimetric GST enzyme assay. Z’-factor values above 0.5 were observed for both assays indicating good separation between the protein interaction signals and negative control background signals, although relatively high background signals were observed for the mammalian interaction due to non-specific binding of murine TPR2A to the plate. Designed human and P. falciparum TPR peptides were observed to be effective inhibitors of the mammalian and P. falciparum interactions, demonstrating the assay’s ability to respond to inhibitor compounds. Comparison of assay performance using GST assay kit reagents and lab- prepared reagents showed the assay was more efficient using lab-prepared reagents, however, lower GST signals were observed when comparing assay performance using a custom prepared Ni-NTA plate to a purchased Ni-NTA plate. The Hsp90-Hop interaction assays were also performed using an alternative assay format in which the GST-TPR2A fusion proteins were immobilised on glutathione-coated plates and binding of the His-tagged C-terminal domains detected with a nickel-horseradish peroxidase (HRP) conjugate and a colorimetric HRP substrate. The assay showed higher interaction signals for the P. falciparum proteins but comparatively low signals for the mammalian proteins. Z’-factor values for the assay were above 0.8 for both protein sets, suggesting this assay format is superior to the GST assay. However, further optimisation of this assay format is required. This study demonstrated direct binding of PfHsp90-PfHop in vitro and established a novel and robust PfHsp90-PfHop interaction assay format that can be used in future screening campaigns.
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