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A case-series evaluation of the impact and processes of a service-learning programme on and for caregivers and their children with neurodevelopmental disabilities

  • Authors: Cooke, Nicole
  • Date: 2019
  • Subjects: Developmentally disabled children -- Care , Caregivers -- Training of , Service learning -- Case studies
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/96691 , vital:31309
  • Description: This thesis presents a series of three case studies from data collected as part of a research project exploring the process and impact of a service-learning programme with caregivers and their children with neurodevelopmental disabilities. Following a descriptive case series design, both quantitative and qualitative data are presented to create a comprehensive and rich understanding of each case. In particular, the data tracks change processes in the subjective well-being of the caregiver, the quality of the caregiver-child relationship and the functional development of the child over a twenty-one-week period of receiving public health services and an eight-week period of adding the service-learning programme. The paper also presents qualitative data on the caregivers’ perceptions of and experiences of the public services and the servicelearning programme that the caregivers and their children received. The findings provide important insight into the caregivers’ perceptions of giving and receiving care, with the caregivers’ experiencing significant levels of distress and prominent barriers to accessing healthcare that were seemingly eased with the addition of the service-learning programme. The findings also point to a notable disparity between the quantitative findings and the qualitative interviews with questions being raised about the research being viewed as an intervention in itself.
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A Century of South African Theatre

  • Authors: Krueger, Anton
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/229623 , vital:49694 , xlink:href="https://doi.org/10.1080/10137548.2020.1716515"
  • Description: In many ways, this is an updated repackaging of Loren Kruger's seminal work of 20 years ago, Plays, Pageants and the Drama of South Africa (1999). The material has been extensively revised and reworked using similar categories as the first book, including: pageantry and representations of nationhood, neo-colonial theatre, urbanization and its consequences; the rise of Afrikaans theatre; theatres of resistance; black consciousness; and contemporary theatre. Some of these sections have been extended (such as a longer discussion of HIE Dhlomo) and there is also a completely new section which has not been published elsewhere on current theatre trends (cleverly titled “The Constitution of South African Theatre at the Present Time”).
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A comparative study of CERBER, MAKTUB and LOCKY Ransomware using a Hybridised-Malware analysis

  • Authors: Schmitt, Veronica
  • Date: 2019
  • Subjects: Microsoft Windows (Computer file) , Data protection , Computer crimes -- Prevention , Computer security , Computer networks -- Security measures , Computers -- Access control , Malware (Computer software)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/92313 , vital:30702
  • Description: There has been a significant increase in the prevalence of Ransomware attacks in the preceding four years to date. This indicates that the battle has not yet been won defending against this class of malware. This research proposes that by identifying the similarities within the operational framework of Ransomware strains, a better overall understanding of their operation and function can be achieved. This, in turn, will aid in a quicker response to future attacks. With the average Ransomware attack taking two hours to be identified, it shows that there is not yet a clear understanding as to why these attacks are so successful. Research into Ransomware is limited by what is currently known on the topic. Due to the limitations of the research the decision was taken to only examined three samples of Ransomware from different families. This was decided due to the complexities and comprehensive nature of the research. The in depth nature of the research and the time constraints associated with it did not allow for proof of concept of this framework to be tested on more than three families, but the exploratory work was promising and should be further explored in future research. The aim of the research is to follow the Hybrid-Malware analysis framework which consists of both static and the dynamic analysis phases, in addition to the digital forensic examination of the infected system. This allows for signature-based findings, along with behavioural and forensic findings all in one. This information allows for a better understanding of how this malware is designed and how it infects and remains persistent on a system. The operating system which has been chosen is the Microsoft Window 7 operating system which is still utilised by a significant proportion of Windows users especially in the corporate environment. The experiment process was designed to enable the researcher the ability to collect information regarding the Ransomware and every aspect of its behaviour and communication on a target system. The results can be compared across the three strains to identify the commonalities. The initial hypothesis was that Ransomware variants are all much like an instant cake box consists of specific building blocks which remain the same with the flavouring of the cake mix being the unique feature.
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A comparative study of the singlet oxygen generation capability of a zinc phthalocyanine linked to graphene quantum dots through π-π stacking and covalent conjugation when embedded in asymmetric polymer membranes

  • Authors: Mafukidze, Donovan M , Nyokong, Tebello
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/187461 , vital:44655 , xlink:href="https://doi.org/10.1016/j.molstruc.2018.11.096"
  • Description: Following the establishment of graphene quantum dots as potential phthalocyanine supports in photoactive membrane preparation for phthalocyanines lacking linkage functional groups, the practical efficiency of p-p stacking versus covalent linkage was investigated. Synthesized materials were characterized using FT-IR, Raman, powder X-ray diffraction, and UVeVis spectroscopies and also by transmission electron and scanning electron microscopies. Phthalocyanine loadings onto graphene quantum dots of 0.40 mg/mg and 0.14 mg/mg (Pc mass/conjugate mass) for the p-p stacked and covalent linked conjugates respectively were observed. Covalent linkage to graphene quantum dots proved to be functionally superior to p-p linkage, where singlet oxygen quantum yield value of the phthalocyanine in the membrane for the covalent linked conjugate was approximately twice that of the p-p stacked membrane.
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A computational analysis to decipher the pathways of stability, uncoating and antigenicity of human enterovirus capsids

  • Authors: Ross, Caroline Jane
  • Date: 2019
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/114788 , vital:34035 , 10.21504/10962/114788
  • Description: Expected release date-April 2021
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A content analysis of psychology Masters theses from South African universities

  • Authors: Robson, Brian
  • Date: 2019
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/113924 , vital:33845
  • Description: Expected release date-April 2022
  • Full Text: false

A continental-scale validation of ecosystem service models

A corporate social responsibility (CSR) analysis of the transformation of the mobile telephone industry of South Africa

  • Authors: Nyamande, Godfrey
  • Date: 2019
  • Subjects: Social responsibility of business -- South Africa , Cell phone systems -- Moral and ethical aspects -- South Africa , Mobile communication systems -- Moral and ethicsl aspects -- South Africa , Telecommunication -- Moral and ethicsl aspects -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/93887 , vital:30967
  • Description: Corporate Social Responsibility (CSR) requires companies to fulfil certain responsibilities in society that are outside of the core operational activities of the company. The socio-economic dynamics of the region or country that the company operates from, as well as the pressures those stakeholders tend to apply, have a bearing on the direction that the CSR development takes. Mirvis and Googins (2006) described the CSR developmental path followed by international companies. Before that Carroll (1991) had suggested a developmental pyramid that suggested that philanthropy represented the highest level of CSR development. This pyramid was later revised by Visser (2005) in order to suit the African environment. In South Africa CSR development is mainly driven by legislation through the BEE Act of 2003. This has resulted in the birth of industry charters that guide the development of CSR in different industries. To fulfil the requirements of the charter and score vital B-BBEE points, companies have to engage with both internal and external stakeholders, holistically. One such industry is the telecommunications industry, which formed the basis for this research, with special emphasis on the mobile telecommunications industry. The research set out to explore how the industry charter and company practices compared with the existing literature on CSR. The aim of this research was therefore to analyse the existing CSR practices in the mobile telecommunication industry in South Africa, where the B-BBEE Act plays a pivotal role in influencing practice. Using publically available documents, this research conducted an analysis of the B-BBEE components in the telecommunications charter as the catalyst to development of CSR in the South African mobile telecommunications industry, with the three dominant companies, - MTN, Vodacom and Cell C – being utilised as case studies. Key research findings were that transformation is still low in terms of equitable gender and racial representation at the top management level. The industry charter attempts to address these and other social challenges and economic problems. However, it does not address ecological issues that may emanate from the industry operations. Therefore, a CSR assessment framework that addresses all stakeholders for sustainable economic development is proposed.
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A correlational analysis investigating relationships between gender role ideology and attitudes towards gender-based violence

  • Authors: Krutani, Siposetu
  • Date: 2019
  • Subjects: Women -- Violence against -- South Africa , Sex role -- Psychological aspects -- South Africa , Male domination (Social structure) -- South Africa , Rhodes University -- Students -- Attitudes , Rape in universities and colleges -- South Africa , Social movements -- South Africa -- Makhanda , Women college students -- Violence against -- South Africa , Male college students -- South Africa -- Attitudes , Women college students -- Psychology -- South Africa , Male college students -- Psychology -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/96658 , vital:31305
  • Description: This study forms part of a larger project investigating attitudes towards intimate partner violence, dating violence and other forms of gender-based violence with the Rhodes University context. The primary purpose was to establish a baseline descriptive understanding of participants‟ attitudes towards and perceptions of gender-based violence. With the aim to generate results that would somehow inform the larger project, the current study sought to investigate whether a relationship exists between gender-role ideology and attitudes towards gender-based violence amongst a university population which was inclusive of registered students and employees of the university (n = 308). Four samples were categorised: student sample, academic staff sample, administrative support staff sample and operational support staff sample. A once-off, cross sectional survey design was used to obtain the data. The results of the study revealed that the participants in the study uphold largely non-traditional gender-role ideologies, are generally intolerant of dating violence and are rejecting of rape myths. As predicted in the literature, the study revealed that demographics such as gender, religion, age, level of education, number of years spent in the institution, race, and student accommodation have an impact on the relationship between adherence to traditional gender-role ideology and tolerance towards dating violence, as well as on the relationship between adherence to traditional gender-role ideology and rape myth acceptance and the relationship between rape myth acceptance and tolerance towards dating violence. The study contributes to the growing body of knowledge on gender-based violence in institutions of higher learning and could help improve sexual violence prevention programmes in such contexts.
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A critical analysis of A2 Fast Track Lowveld sugar cane farms in Zimbabwe in global value chains: interrogating the lives of farmers and farm labourers

  • Authors: Chingono, Kudakwashe Rejoice
  • Date: 2019
  • Subjects: International trade , Sugar trade -- Zimbabwe , Sugar growing -- Zimbabwe -- Social aspects , Agriculture -- Zimbabwe -- Social aspects
  • Language: English
  • Type: text , Thesis , Masters , MSocSci
  • Identifier: http://hdl.handle.net/10962/93933 , vital:30972
  • Description: The sugar cane industry has for many years been a lucrative business with a booming global market. In Zimbabwe, the sugar cane industry is no exception, as it has been regarded as one of the most efficient in the region and even in the world. The sugar cane farms and mills in Zimbabwe are located in Triangle and Chiredzi, in the south-eastern part of the country and they are under the ownership of Tongaat Hullet and the Zimbabwean A2 farmers. The focus of this is on the A2 fast track farms in Hippo Valley, which are now owned by black farmers but as out-growers for Tongaat Hullet. The crucial question addressed in the thesis is whether the A2 sugar cane farmers and their workers, located at the production end of the sugar cane global value chain, are benefitting from their involvement in this value chain. A number of scholars argue that global value chains lead to economic and social upgrading at the production end of the chain, based on thoughts contained in modernisation and trickledown theory. There is an assumption, then, that integration into the global economy leads to economic upgrading which translates into social upgrading. In drawing upon critical global value theorists, bolstered by the Marxist perspective, considers the importance of a more critical view of global value chains in relation to the sugar cane industry in Zimbabwe, with the particular focus on A2 farms. Thus, the main objective of the thesis is to consider the lives and livelihoods of A2 sugar cane farmers and sugar cane workers through a case study, in the context of global value chains and arguments around economic and social upgrading. This is pursued through a case study of six A2 farms, which involved interviewing farmers, supervisors, and both permanent and temporary workers. The thesis concludes that there is no significant evidence of social upgrading amongst the labour force, and that the A2 farmers are in constant tension with Tongaat Hullet in seeking to engage in economic upgrading of their status as commercial farmers.
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A critical analysis of development NGO programmes in rural areas: a case study of East Cape Agricultural Research Project in South Africa

  • Authors: Sanyangore, Agnes
  • Date: 2019
  • Subjects: East Cape Agricultural Research Project , Non-governmental organization -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa -- Eastern Cape , Land reform -- South Africa -- Eastern Cape , Land tenure -- South Africa -- Eastern Cape
  • Language: English
  • Type: text , Thesis , Masters , MSocSc
  • Identifier: http://hdl.handle.net/10962/96187 , vital:31248
  • Description: For a number of decades now, development non-governmental organisations (DNGOs) have been central to the world-wide development system which involves funding from international donors. Overall, DNGOs rely quite fundamentally on their donors for organisational sustainability, such that upward accountability to donors is inevitable. At the same time, as development agents, DNGOs are often celebrated for the deep participatory methodologies used when engaging with the beneficiaries of their programmes, leading to significant downward accountability – as least potentially. Often, for DNGOs, an awkward tension between upward and downward accountability exists. This thesis considers this tension by examining a DNGO in South Africa, namely, the East Cape Agricultural Research Project (ECARP), which focuses on questions around land redistribution. ECARP works with farm labourers and dwellers on commercial farms and small-scale farmers on redistributed farms. In the context of a broader understanding of ECARP’s mission, capacities and programmes, the thesis looks specifically at ECARP’s food security and sovereignty programme amongst small-scale farmers on redistributed farms. By drawing upon Interface theory, the thesis discusses in detail the diverse manner in which ECARP uses participatory methodologies in this particular programme. The thesis concludes that there is a reasonable degree of downward accountability in this programme, but that this does not distract from the fact that ECARP remains within the tension-riddled space marked by dual demands for accountability.
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A critical analysis of selected teachers’ perceptions and experiences of the role that visualisation processes play in their Van Hiele level 1 teaching to migrate their learners to the next Van Hiele level

  • Authors: Munichinga, Ben Muyambango
  • Date: 2019
  • Subjects: Hiele, Pierre M. van. Structure and insight , Visualization , Mathematics -- Study and teaching (Secondary) -- Namibia , Geometry -- Study and teaching (Secondary) -- Namibia , Mathematics -- Study and teaching (Secondary) -- Activity programs -- Namibia
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/96735 , vital:31313
  • Description: Learning is a process that involves building on prior knowledge, enriching and exchanging existing understanding where learners’ knowledge base is scaffolded in the construction of knowledge. Research on the teaching and learning of geometry in mathematics suggests that physical manipulation experiences, especially of shapes, is an important process in learning at all ages. The focus of the study was the migration of Grade 8 learners from one Van Hiele level to the next as a result of teachers incorporating visualisation processes and Van Hiele phases of instructions in their teaching. The study underpinned by the social constructivist’s theory, therefore aimed at teachers developing visual materials and using Van Hiele’s phases of instruction to teach two dimensional figures in Geometry. The study was carried out in Namibia, Zambezi region in Bukalo circuit. It involved four schools, with 93 learners and three teacher participants. The research is an interpretive case study of a planned intervention programme, which took a four weeks to complete. Participating learners wrote a Van Hiele Geometric test prior and post the intervention programme to determine their geometric level of thought. Participating teachers all received training on visualisation in mathematics and the Van Hiele theory before the intervention. During the intervention, teacher planned and each taught three lessons on two-dimensional figures. Qualitative data was collected from classroom observation, stimulus recall interviews and focus group interviews. Quantitative data came from the pre and post-test of learners. This study found that on average, Grade 8 learners who participated in the study were operating at levels lower than expected of pupils at their stage of schooling. This study also found that, visualisation processes and the Van Hiele phases are effective when used in geometry lessons to migrate learners from lower Van Hiele levels to higher. For teachers in the same circuit, partnership and planning of difficult topics on an agreed regular basis is recommended. When planning lessons teachers are encouraged to take advantage of the Van Hiele phases of instructions. This study thus recommends the incorporation of visualisation strategies of teaching geometry in particular at primary and lower secondary levels. Mathematics teachers are further encouraged to design visual materials such as Geoboards to use for every topic in geometry. Such visual materials should be carefully developed and evaluated to ensure that their use in the classroom is effectively linked to concepts under discussion in a given lesson.
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A critical realist exploration of the culture of resistance in educational technology integration practices at a South African university

  • Authors: Tshuma, Nompilo
  • Date: 2019
  • Subjects: Critical realism , Educational technology -- South Africa , Education, Higher -- Effect of technological innovations on -- South Africa , College teachers -- South Africa , College teaching -- Sociological aspects -- South Africa
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/72318 , vital:30033
  • Description: This thesis seeks to address a number of troubling concerns related to research and practice in the field of educational technology in South African higher education. Firstly, educational technology research has been criticised for a lack of theoretical rigour resulting in perspectives that are tightly focused mostly on practice but fail to adequately interrogate the socio-political complexities of integrating educational technology. Secondly, while research in the field has been criticised for failing to adequately contextualise the study of educational technology, it also fails to interrogate the impact of colonial legacies and Western-developed technologies on integration practices. Thirdly, there seems to be a disconnect between academics’ practices and choices with educational technology, and the expectations and assumptions of educational technologists. As such, this thesis predominantly follows inductive reasoning where literature and theory are applied to the empirical situation retrospectively in order to avoid the potential influences and biases of mostly Western-driven discourses on educational technology integration practices. Critical realism is used to ‘underlabour’ this study. This meta-theory asserts that there are multiple perspectives of an independent reality, and the work of research is to use these perspectives to draw closer to an understanding of that reality. As such, it allows me to interrogate my perspectives firstly, and secondly those of my research participants, about factors that constrain educational technology integration in the South African context through the use of theory (abstract concepts) and data (research participants’ multiple perspectives). However, critical realism is somewhat cautious in how to access this reality. Therefore, a critical ethnographic epistemology is employed to strengthen critical realism’s aim of accessing knowledge. A critical epistemology emphasises exposing hidden power structures, value judgements as well as self-knowledge and reflexivity. The thesis thus shows how a critical realist ontology could be complemented by a critical ethnographic methodology, particularly in critically-orientated research that has an emancipatory focus which seeks to uncover the socio-political context within which educational technology practices take place. A key argument is that critical realism can be employed as an ontological underlabourer for critical research because of: 1) its immanent critique of traditionally-accepted philosophies, 2) its emphasis on critique of our knowledge claims and value judgements, 3) its insistence that knowledge of the social world necessarily precedes emancipation, and 4) its different conceptions of power (oppressive power and transformatory power). This critical ethnographic research is conducted in a South African university with eight female academics. Data collection is in the form of interviews, observations and reflections, as well as informal and work-related interactions. At each data collection moment, I have had to be reflexively aware of my positionality as an educational technologist, the impact of a colonially-motivated methodology and an ethically-aware approach that seeks to put the needs of the research participants first. Critical ethnography’s meaning-making and critical realism’s abduction and retroduction are used to analyse and make sense of the data. In my attempt to contextualise the study’s findings, I first uncover structural forces and their impact on the academic role before attempting to correlate this with educational technology practices. The study’s findings point to two main structural forces in the socio-political context of South African higher education: the teaching/research tension and the elevation of one dominant culture. In terms of the teaching/research tension, the female academics in this study have to balance the urgent teaching function with the valued research function. They struggle to find this balance because of ambiguous messages from different structures, their passion for teaching, oppressive departmental dynamics and the pressures of their career trajectory. The elevation of one dominant culture is demonstrated through both oppressive cultural practices and untransformed curricula. The study shows that academics mitigate these structural constraints mostly through subtle every day resistance that seeks to mitigate their effect on both the academics and, where applicable, their students. Archer’s morphogenetic/morphostatic cycle is used retrospectively, in response to fieldwork, to conceptualise why this resistance comes about. A resistance framework developed using Archer is then used to understand educational technology choices and practices. The results of the research show that while academics are often pictured as resistant to technology as a response to different barriers, they actually often employ technology to resist structural forces. That is, with this thesis I show that there is a focus on resistance with technology rather than resistance to technology. The study shows how the research participants resist structural forces (teaching tension and dominant culture) by using technology to create safe and responsive learning spaces. As such, this thesis challenges educational technologists to re-think the way they support academics by recommending support strategies that acknowledge both the structural forces in the South African higher education context, as well as the culture of resistance, both of which impact academics’ educational technology choices and practices.
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A design experiment exploring the influence of visual and kinesthetic tools in learning Grade 8 linear algebra in a Namibian secondary school

  • Authors: Kalua, Enos
  • Date: 2019
  • Subjects: Algebra -- Study and teaching (Secondary)-- Namibia , Mathematics -- Study and teaching (Secondary)-- Namibia , Information visualization , Visual learning -- Case studies
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/92683 , vital:30724
  • Description: Based on a broad literature review, understanding algebra is a challenge among learners in middle schools around the world. Early researches also indicated that algebra is often taught through inherent symbols and procedures. This does not exclude Namibian learners in secondary schools whom I have worked with for over 10 years. Examination reports (2014, 2016 and 2017) serve as evidence that learners performed poorly (below 45%) in the area of algebra, with these reports indicating that teachers need to strongly emphasise the issue of solving linear equations. Therefore, this study presents a proposed design research in an attempt to help learners develop meaningful understanding of linear algebra at Grade 8 level. Eight learners whose ages ranged from 13 - 14 years from one Namibian secondary school in Oshikoto region, in northern Namibia, were the participants in this study. The learners represented different groups of learning abilities, ranging from low learning abilities to high learning abilities. The designed programme for this intervention consisting of eight lessons was planned for three weeks and the lessons were conducted in the afternoon to avoid any interruption with normal learning hours. The study used four tools for data collection, namely, benchmark tests (pre-test and post-test), observation, focus groups and unstructured interviews. The data collected for this study was inductively analysed. The purpose of this study was to determine whether and how the specific visual and kinaesthetic teaching tools (diagrams, expansion box and balance method) used may have contributed to learners’ understanding of algebraic concepts and techniques (variables, expressions and equations). The study used diagrams (geometrical plane shapes) for separating terms, an expansion box for expanding brackets and the balance method for solving linear equations. The study revealed the use of diagrams helped the learners in understanding the separation of variable and constant terms when simplifying expressions through addition and/or subtraction. Moreover, the study also revealed that the use of an expansion box was useful for the learners in understanding expansion of brackets in expressions with more than one term. Regarding the use of the balance method, the study showed that learners were already able to solve linear equations by the transfer method, hence, the balance method was not necessary.
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A development method for deriving reusable concurrent programs from verified CSP models

  • Authors: Dibley, James
  • Date: 2019
  • Subjects: CSP (Computer program language) , Sequential processing (Computer science) , Go (Computer program language) , CSPIDER (Open source tool)
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/72329 , vital:30035
  • Description: This work proposes and demonstrates a novel method for software development that applies formal verification techniques to the design and implementation of concurrent programs. This method is supported by a new software tool, CSPIDER, which translates machine-readable Communicating Sequential Processes (CSP) models into encapsulated, reusable components coded in the Go programming language. In relation to existing CSP implementation techniques, this work is only the second to implement a translator and it provides original support for some CSP language constructs and modelling approaches. The method is evaluated through three case studies: a concurrent sorting array, a trialdivision prime number generator, and a component node for the Ricart-Agrawala distributed mutual exclusion algorithm. Each of these case studies presents the formal verification of safety and functional requirements through CSP model-checking, and it is shown that CSPIDER is capable of generating reusable implementations from each model. The Ricart-Agrawala case study demonstrates the application of the method to the design of a protocol component. This method maintains full compatibility with the primary CSP verification tool. Applying the CSPIDER tool requires minimal commitment to an explicitly defined modelling style and a very small set of pre-translation annotations, but all of these measures can be instated prior to verification. The Go code that CSPIDER produces requires no intervention before it may be used as a component within a larger development. The translator provides a traceable, structured implementation of the CSP model, automatically deriving formal parameters and a channel-based client interface from its interpretation of the CSP model. Each case study demonstrates the use of the translated component within a simple test development.
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A dynamics based analysis of allosteric modulation in heat shock proteins

  • Authors: Penkler, David Lawrence
  • Date: 2019
  • Subjects: Heat shock proteins , Molecular chaperones , Allosteric regulation , Homeostasis , Protein kinases , Transcription factors , Adenosine triphosphatase , Cancer -- Chemotherapy , Molecular dynamics , High throughput screening (Drug development)
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/115948 , vital:34273
  • Description: The 70 kDa and 90 kDa heat shock proteins (Hsp70 and Hsp90) are molecular chaperones that play central roles in maintaining cellular homeostasis in all organisms of life with the exception of archaea. In addition to their general chaperone function in protein quality control, Hsp70 and Hsp90 cooperate in the regulation and activity of some 200 known natively folded protein clients which include protein kinases, transcription factors and receptors, many of which are implicated as key regulators of essential signal transduction pathways. Both chaperones are considered to be large multi-domain proteins that rely on ATPase activity and co-chaperone interactions to regulate their conformational cycles for peptide binding and release. The unique positioning of Hsp90 at the crossroads of several fundamental cellular pathways coupled with its known association with diverse oncogenic peptide clients has brought the molecular chaperone under increasing interest as a potential anti-cancer target that is crucially implicated with all eight hallmarks of the disease. Current orthosteric drug discovery efforts aimed at the inhibition of the ATPase domain of Hsp90 have been limited due to high levels of associated toxicity. In an effort to circumnavigate this, the combined focus of research efforts is shifting toward alternative approaches such as interference with co-chaperone binding and the allosteric inhibition/activation of the molecular chaperone. The overriding aim of this thesis was to demonstrate how the computational technique of Perturbation response scanning (PRS) coupled with all-atom molecular dynamics simulations (MD) and dynamic residue interaction network (DRN) analysis can be used as a viable strategy to efficiently scan and accurately identify allosteric control element capable of modulating the functional dynamics of a protein. In pursuit of this goal, this thesis also contributes to the current understanding of the nucleotide dependent allosteric mechanisms at play in cellular functionality of both Hsp70 and Hsp90. All-atom MD simulations of E. coli DnaK provided evidence of nucleotide driven modulation of conformational dynamics in both the catalytically active and inactive states. PRS analysis employed on these trajectories demonstrated sensitivity toward bound nucleotide and peptide substrate, and provided evidence of a putative allosterically active intermediate state between the ATPase active and inactive conformational states. Simultaneous binding of ATP and peptide substrate was found to allosterically prime the chaperone for interstate conversion regardless of the transition direction. Detailed analysis of these allosterically primed states revealed select residue sites capable of selecting a coordinate shift towards the opposite conformational state. In an effort to validate these results, the predicted allosteric hot spot sites were cross-validated with known experimental works and found to overlap with functional sites implicated in allosteric signal propagation and ATPase activation in Hsp70. This study presented for the first time, the application of PRS as a suitable diagnostic tool for the elucidation and quantification of the allosteric potential of select residues to effect functionally relevant global conformational rearrangements. The PRS methodology described in this study was packaged within the Python programming environment in the MD-TASK software suite for command-line ease of use and made freely available. Homology modelling techniques were used to address the lack of experimental structural data for the human cytosolic isoform of Hsp90 and for the first time provided accurate full-length structural models of human Hsp90α in fully-closed and partially-open conformations. Long-range all-atom MD simulations of these structures revealed nucleotide driven modulation of conformational dynamics in Hsp90. Subsequent DRN and PRS analysis of these MD trajectories allowed for the quantification and elucidation of nucleotide driven allosteric modulation in the molecular chaperone. A detailed PRS analysis revealed allosteric inter-domain coupling between the extreme terminals of the chaperone in response to external force perturbations at either domain. Furthermore PRS also identified several individual residue sites that are capable of selecting conformational rearrangements towards functionally relevant states which may be considered to be putative allosteric target sites for future drug discovery efforts Molecular docking techniques were employed to investigate the modulation of conformational dynamics of human Hsp90α in response to ligand binding interactions at two identified allosteric sites at the C-terminal. High throughput screening of a small library of natural compounds indigenous to South Africa revealed three hit compounds at these sites: Cephalostatin 17, 20(29)-Lupene-3β isoferulate and 3'-Bromorubrolide F. All-atom MD simulations on these protein-ligand complexes coupled with DRN analysis and several advanced trajectory based analysis techniques provided evidence of selective allosteric modulation of Hsp90α conformational dynamics in response to the identity and location of the bound ligands. Ligands bound at the four-helix bundle presented as putative allosteric inhibitors of Hsp90α, driving conformational dynamics in favour of dimer opening and possibly dimer separation. Meanwhile, ligand interactions at an adjacent sub-pocket located near the interface between the middle and C-terminal domains demonstrated allosteric activation of the chaperone, modulating conformational dynamics in favour of the fully-closed catalytically active conformational state. Taken together, the data presented in this thesis contributes to the understanding of allosteric modulation of conformational dynamics in Hsp70 and Hsp90, and provides a suitable platform for future biochemical and drug discovery studies. Furthermore, the molecular docking and computational identification of allosteric compounds with suitable binding affinity for allosteric sites at the CTD of human Hsp90α provide for the first time “proof-of-principle” for the use of PRS in conjunction with MD simulations and DRN analysis as a suitable method for the rapid identification of allosteric sites in proteins that can be probed by small molecule interaction. The data presented in this section could pave the way for future allosteric drug discovery studies for the treatment of Hsp90 associated pathologies.
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A framework for scoring and tagging NetFlow data

  • Authors: Sweeney, Michael John
  • Date: 2019
  • Subjects: NetFlow , Big data , High performance computing , Event processing (Computer science)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/65022 , vital:28654
  • Description: With the increase in link speeds and the growth of the Internet, the volume of NetFlow data generated has increased significantly over time and processing these volumes has become a challenge, more specifically a Big Data challenge. With the advent of technologies and architectures designed to handle Big Data volumes, researchers have investigated their application to the processing of NetFlow data. This work builds on prior work wherein a scoring methodology was proposed for identifying anomalies in NetFlow by proposing and implementing a system that allows for automatic, real-time scoring through the adoption of Big Data stream processing architectures. The first part of the research looks at the means of event detection using the scoring approach and implementing as a number of individual, standalone components, each responsible for detecting and scoring a single type of flow trait. The second part is the implementation of these scoring components in a framework, named Themis1, capable of handling high volumes of data with low latency processing times. This was tackled using tools, technologies and architectural elements from the world of Big Data stream processing. The performance of the framework on the stream processing architecture was shown to demonstrate good flow throughput at low processing latencies on a single low end host. The successful demonstration of the framework on a single host opens the way to leverage the scaling capabilities afforded by the architectures and technologies used. This gives weight to the possibility of using this framework for real time threat detection using NetFlow data from larger networked environments.
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A functional ontology for information systems

  • Authors: Motara, Yusuf, M , Van der Schyff, Karl
  • Date: 2019
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/428936 , vital:72547 , https://hdl.handle.net/10520/EJC-1d75ba3e4a
  • Description: The ontology of information systems — the way in which knowledge claims, and thus theories, are conceptualised and represented — is of particular importance in the information systems field, due to its reliance on relations between entities. This work proposes, demonstrates, and evaluates an alternative ontology for theory description which is arguably more powerful and more expressive than the dominant ontological model.
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A Genealogy of Puberty Science: Monsters, Abnormals, and Everyone Else

  • Authors: Pinto, Pedro , Macleod, Catriona I
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/434065 , vital:73029 , ISBN 9781315142098 , https://doi.org/10.4324/9781315142098
  • Description: A Genealogy of Puberty Science explores the modern invention of puberty as a scientific object. Drawing on Foucault’s genealogical analytic, Pinto and Macleod trace the birth of puberty science in the early 1800s and follow its expansion and shifting discursive frameworks over the course of two centuries. Offering a critical inquiry into the epistemological and political roots of our present pubertal complex, this book breaks the almost complete silence concerning puberty in critical theories and research about childhood and adolescence. Most strikingly, the book highlights the failure of ongoing medical debates on early puberty to address young people’s sexual and reproductive embodiment and citizenships. A Genealogy of Puberty Science will be of great interest to academics, researchers and postgraduate students in the fields of child and adolescent health research, critical psychology, developmental psychology, health psychology, feminist and gender studies, medical history, science and technology studies, and sexualities and reproduction studies.
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A historical sociolinguistic study on the conceptualisation and application of justice and law kwisizwe samaXhosa as documented in and extracted From SEK Mqhayi And W.W. Gqoba’s selected writings

  • Authors: Ntshingana, Sanele
  • Date: 2019
  • Subjects: Gqoba, William Wellington , Mqhayi, S. E. K. , Xhosa literature -- History and criticism , Law in literature , Justice in literature
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/115339 , vital:34115
  • Description: This study seeks to investigate the original meanings contained in lexical terms relating to law (umthetho) and justice (ubulungisa) and their application in the precolonial Xhosa social society as they make appearance in SEK Mqhayi’s novel Ityala lamawele (1914) and WW Gqoba’s Isizwe esinembali, (1873-188/2015). Both of these works were written and initially published at the early point of contact of amaXhosa with the art of writing, and so are set in a ‘traditional’ setting (in the case of Mqhayi) and at early contact with European societies in Eastern Nguni region. This academic endeavour is undertaken by employing critical discourse theoretical framework. The purpose is to investigate the conceptualisation of law and justice amongst amaXhosa, and the extent to which this conceptualisation reflects the philosophical worldview of amaXhosa, as embedded in their language. The paper makes inferences about conceptualisation of law and justice in precolonial Xhosa social settings, and offers proposals on what this conceptual understanding could mean if its potential contribution to the contemporary understanding and application of law and justice in South Africa could be tapped into. The motivation for this study emanates from the current intellectual contestations in higher education that today’s curricula present western knowledge systems as universal while marginalising indigenous epistemologies in teaching, learning and research practices. At the centre of these debates is how research, social and scientific thinking in humanities, is profoundly shaped by imported, racist, western “canonical” texts and theories. The arguments presented by various scholars argue that this enterprise firmly roots the collective imagination of students about the past and present in racist Eurocentric schematic frames, thus creating a problem of identity loss, and an intentional distortion of historical truths. The space for knowledge systems and experiences reflecting African memory and imagination is not only neglected, but distorted too. In this context, the study seeks to delve deeper into how African languages can be used to reconstruct knowledge systems that reflect African ways of understanding society as part of creating a curriculum that depicts “multiversal” ways of knowing (Tisani 2000; Santos, 2014). This study makes several findings, chief amongst which is that the legal and justice systems of the precolonial Xhosa society was both corrective as opposed to today’s punitive court system that South Africa inherited, largely from the West. It seeks to prove that AmaXhosa’s precolonial legal and justice system was focused more on reintegrating the offender back into society. The study further will show how the precolonial amaXhosa justice system was embedded in the concepts of ubulungisa (correct and re-intergrate) and isohlwayo (that which brings one to basics). Through discourse analysis of the early literary isiXhosa texts, the thesis discovers that the application of ubulungisa amongst amaXhosa back then was consistent with the philosophies embedded in the concepts. By exposing the collaboration networks between the white missionaries and the colonial administrators of the nineteenth century, the thesis will show how conspiracies were directed at erasing and displacing these indigenous epistemologies and to replacing them with colonial memories. To this end, missionary accounts, explorer diary entries and reports and early lexicographic material were produced and archived. Furthermore, this study makes a proposition that early written Xhosa texts be entrenched in the today’s curricula in order inform the process of making sense of the social experiences and knowledge systems of the indigenous people of South Africa, from the precolonial-past to the present. Throughout the study, the thesis presents a proposition these early Xhosa texts be studied in relation to their intellectual contributions. This, it is hoped, will boldly challenge the canonised knowledge and racist assumptions about the African knowledge systems and experiences.
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