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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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A hydrogeological investigation of Grahamstown, assessing both the dynamics and quality of the local groundwater system

  • Authors: Smetherham, Kyle Norman
  • Date: 2019
  • Subjects: Hydrogeology -- South Africa -- Makhanda , Water quality -- South Africa -- Makhanda , Groundwater -- Quality -- South Africa -- Makhanda
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/94444 , vital:31045
  • Description: In many parts of South Africa, complete allocation of surface water reservoirs together with current drought conditions has led to serious water shortages and subsequent awareness regarding the importance to save water. Grahamstown is no different, with water problems relating to low supply and high demand being compounded by insufficient treatment capacity and aging infrastructure. Groundwater is an alternative water resource that could potentially act as a supplementary and/or emergency supply to the town, reducing the reliability on surface reservoirs. Groundwater however, is a hidden resource and requires an understanding of various aquifer properties and continuous monitoring and modelling so not to permanently disrupt the natural system but rather achieve sustainable management. Grahamstown is situated towards the northern extent of the Cape Fold Belt (CFB) system, within a synclinal fold structure. The local geology forms two local aquifer systems beneath Grahamstown that directly influence both the dynamics and quality of the groundwater. These underground reservoirs are the Witpoort and Dwyka aquifers and can be described as a semi-confined, fractured, quartzitic sandstone aquifer and an unconfined, fractured, tillite aquifer, respectively. Separating these aquifer systems is a shale aquitard, although due to the fractured nature of the rocks in the region there is most likely some groundwater interaction between them. Evaluation of geological formations together with the monitoring of 31 local boreholes presented a valuable conceptualisation of the local system and allowed for the application of methods to estimate recharge. Recharge estimation is one of the most crucial factors when managing aquifer systems as it can be used to determine what proportion of rainfall contributes to the subsurface reservoir and therefore, the sustainable amount that can be extracted. Various methods have been developed to estimate recharge, however due to the uncertainty surrounding groundwater systems, especially fractured aquifers, it was important to apply multiple methods to validate results. The water-table fluctuation (WTF) and cumulative rainfall departure (CRD) are two methods that were used in the present study to determine recharge. These methods rely on water-table changes in boreholes and specifically how they respond to rainfall events. Along with the WTF and CRD methods, a modelling approach was also used to estimate recharge which focused on the dynamics of a natural groundwater outlet, termed the Fairview Spring. This natural spring system is located just outside the main town of Grahamstown, within the Witpoort aquifer system, and is an important water resource to many residents due to poor supply and quality of municipal water. Monitoring the discharge of this spring allowed for the development of a model which attempts to recreate the discharge conditions observed. Along with groundwater recharge, other processes added to the model include evapotranspiration, storage, interflow spring outflow and groundwater outflow. Several different model simulation scenarios provided valuable insight into the greater groundwater dynamics. In terms of groundwater quality, nine borehole samples and one spring sample were analysed for major ions (Ca, Na, K, Cl, Mg, SO4, HCO3), metals (Cu, Fe, Mn) as well as pH and electrical conductivity. Overall electrical conductivity levels and major ion concentrations were lower in the Witpoort aquifer indicating a better groundwater quality compared to that of the Dwyka aquifer. Of the three metals included in the analysis, Mn proved to be the most significant and the highest concentrations were produced for samples that intersected the shale aquitard unit, suggesting that Mn-containing groundwater is drawn from this geological layer. Development of a supplementary and/or emergency groundwater supply requires careful consideration of the geology, quantity, quality, and recharge in the study site. All these aspects were assessed as well as deliberation into the potential infrastructural costs involved. Through conceptualisation of the system; evidence gathered during basic monitoring; and a simple spring model, the current study aimed to explore certain management strategies and recommend potential options going forward. The hidden nature of the resource together with the heterogeneity of fracture networks creates an inevitable uncertainty surrounding the system. Proper development and management of the aquifer can only be achieved if the system is continually monitored, modelled and utilised sustainably.
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A local portrait of South African counselling psychologists’ endorsement of the values and scope of practice of their profession in relation to their career satisfaction

  • Authors: Ngobeni, Nhlori
  • Date: 2019
  • Subjects: Counseling psychology -- South Africa , Counseling psychologists -- South Africa , Psychology -- South Africa , Psychologists -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/94350 , vital:31038
  • Description: The 2011 revision to the scope of practice of counselling psychology in South Africa has renewed debates about what is it that should distinguish counselling psychology as a distinctive area of practice and research in South Africa. This study reports the findings of a survey of a sample of 228 South African registered counselling psychologists, including the extent to which they endorse the traditional values of their category, the extent to which they endorse the current scope of practice for counselling psychology, and measures of career satisfaction. Findings are that women and white practitioners comprise the large majority of the category. Counselling psychologists strongly endorse most of the traditional values of the category and are generally highly satisfied with their careers. Surprisingly, given these findings, only a large minority indicate that they would choose counselling psychology again knowing what they know now. Most significant, the findings of a multiple regression analysis indicate that endorsement of the scope of practice most strongly predicts career satisfaction scores, followed closely by black racial identification, years of experience, and then endorsement of counselling psychology values. Logistic regression analysis to predict which counselling psychologists would choose counselling psychology again knowing what they know now, revealed that only endorsement of counselling psychology values and endorsement of the scope practice made a significant contribution to predictions. This study provides a snapshot of the current status of South African counselling psychology today and it remains that in the next ten years, there will be significant changes as the category changes across the globe.
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A multi-threading software countermeasure to mitigate side channel analysis in the time domain

  • Authors: Frieslaar, Ibraheem
  • Date: 2019
  • Subjects: Computer security , Data encryption (Computer science) , Noise generators (Electronics)
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/71152 , vital:29790
  • Description: This research is the first of its kind to investigate the utilisation of a multi-threading software-based countermeasure to mitigate Side Channel Analysis (SCA) attacks, with a particular focus on the AES-128 cryptographic algorithm. This investigation is novel, as there has not been a software-based countermeasure relying on multi-threading to our knowledge. The research has been tested on the Atmel microcontrollers, as well as a more fully featured system in the form of the popular Raspberry Pi that utilises the ARM7 processor. The main contributions of this research is the introduction of a multi-threading software based countermeasure used to mitigate SCA attacks on both an embedded device and a Raspberry Pi. These threads are comprised of various mathematical operations which are utilised to generate electromagnetic (EM) noise resulting in the obfuscation of the execution of the AES-128 algorithm. A novel EM noise generator known as the FRIES noise generator is implemented to obfuscate data captured in the EM field. FRIES comprises of hiding the execution of AES-128 algorithm within the EM noise generated by the 512 Secure Hash Algorithm (SHA) from the libcrypto++ and OpenSSL libraries. In order to evaluate the proposed countermeasure, a novel attack methodology was developed where the entire secret AES-128 encryption key was recovered from a Raspberry Pi, which has not been achieved before. The FRIES noise generator was pitted against this new attack vector and other known noise generators. The results exhibited that the FRIES noise generator withstood this attack whilst other existing techniques still leaked out secret information. The visual location of the AES-128 encryption algorithm in the EM spectrum and key recovery was prevented. These results demonstrated that the proposed multi-threading software based countermeasure was able to be resistant to existing and new forms of attacks, thus verifying that a multi-threading software based countermeasure can serve to mitigate SCA attacks.
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A novel axially palladium (II)-Schiff base complex substituted silicon (IV) phthalocyanine

  • Authors: Sen, Pinar , Nyokong, Tebello
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/186813 , vital:44536 , xlink:href="https://doi.org/10.1016/j.poly.2019.114135"
  • Description: In this study, a novel silicon(IV) phthalocyanine is reported for the first time as a phthalocyanine derivative bearing axially a palladium(II)-Schiff base complex. The photophysical and photochemical properties of the new Si(IV)Pc, such as absorption, fluorescence, singlet oxygen quantum yields, triplet state quantum yields and exited state lifetimes were measured in DMSO. The new silicon phthalocyanine displayed very low fluorescence, showing efficient intersystem crossing resulting in high triplet and high singlet oxygen quantum yields in DMSO. When compared with the unsubstituted SiPcCl2, the singlet oxygen quantum yield value (UD = 0.47) in relation to the triplet quantum yield (UT = 0.82), which is an important determinant for PDT applications, increased. The photodynamic antimicrobial chemotherapy activity (PACT) of new Si(IV)Pc towards Staphylococcus aureus was determined in comparison to the unsubstituted SiPcCl2. The results of the photodynamic antimicrobial effect study demonstrated that the Pd(II) complex substituted SiPc (5) possesses excellent photodynamic activity with a reduction percentage value of 99.94% and a log red value of 3.26.
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A novel technique for artificial pack formation in African wild dogs using odour familiarity:

  • Authors: Marneweck, Courtney J , Marchal, Antoine F J , Marneweck, David G , Beverley, Grant , Davies-Mostert, Harriet T , Parker, Daniel M
  • Date: 2019
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/150060 , vital:38935 , https://doi.org/10.3957/056.049.0116
  • Description: Reintroductions are recognized tools for species recovery. However, operations are costly, difficult to implement, and failures are common and not always understood. Their success for group-living species depends on the mimicry of natural processes that promote social integration. Due to fragmented landscapes, human mediated (i.e. artificial) group formation is often required.
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A phenomenological study of Senior Primary school teachers’ understandings of an English Across the Curriculum approach to language teaching in Namibia

  • Authors: Kambonde, Emily
  • Date: 2019
  • Subjects: English teachers -- Training of -- Namibia , English language -- Study and teaching (Elementary) -- Namibia
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/92381 , vital:30718
  • Description: This is a phenomenological study designed to investigate English teachers’ understandings of the concept of English Across the Curriculum (EAC), and the extent to which such understandings inform their pedagogic practices at the Senior Primary phase, in a Namibian context. The study was located within the qualitative, interpretive paradigm, using a multi-method approach of semi-structured interviews, classroom observations and documentary evidence as research instruments. The participants were three English second-language teachers at a primary school in a suburban area. Findings from the study revealed that there were several understandings of EAC, and though there might have been an underlying understanding of the concept, classroom practices were incongruent with what EAC requires. It was also found that there are documents based on social constructivist and Genre Theory in the National Professional Standards for teachers, but teachers were not familiar with the content of these documents and they were not used by teachers as guiding documents on how they need to implement EAC. It is recommended that English teachers receive continuous professional development courses on language development theories and EAC, as well as specific training to implement EAC so that “every teacher can be a language teacher”.
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A physiological study on a commercial reef fish to quantify the relationship between exploitation and climate change resilience

  • Authors: Duncan, Murray Ian
  • Date: 2019
  • Subjects: Chrysoblephus laticeps -- Climatic factors , Chrysoblephus laticeps -- Physiology , Sparidae -- South Africa -- Climatic factors , Reef fishes -- South Africa -- Climatic factors , Fish populations -- South Africa -- Climatic factors , Fish populations -- Measurement , Fish populations -- Monitoring , Fisheries -- South Africa -- Environmental aspects , Ocean temperature -- Physiological effect -- South Africa
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/76541 , vital:30599
  • Description: The persistence of harvested fish populations in the Anthropocene will be determined, above all, by how they respond to the interacting effects of climate change and fisheries exploitation. Predicting how populations will respond to both these threats is essential for any adaptive and sustainable management strategy. The response of fish populations to climate change is underpinned by physiological rates and tolerances, and emerging evidence suggests there may be physiological-based selection in capture fisheries. By quantifying important physiological rates of a model species, the endemic seabream, Chrysoblephus laticeps, across ecologically relevant thermal gradients and from populations subjected to varying intensities of commercial exploitation, this thesis aimed to 1) provide the first physiologically grounded climate resilience assessment for a South African linefish species, and 2) elucidate whether exploitation can drive populations to less physiologically resilient states in response to climate change. To identify physiologically limiting sea temperatures and to determine if exploitation alters physiological trait distributions, an intermittent flow respirometry experiment was used to test the metabolic response of spatially protected and exploited populations of C. laticeps to acute thermal variability. Exploited populations showed reduced metabolic phenotype diversity, fewer high-performance aerobic scope phenotypes, and a significantly lower aerobic scope curve across all test temperatures. Although both populations maintained a relatively high aerobic scope across a wide thermal range, their metabolic rates were compromised when extreme cold events were simulated (8 °C), suggesting that predicted future increases in upwelling frequency and intensity may be the primary limiting factor in a more thermally variable future ocean. The increment widths of annuli in the otoliths of C. laticeps from contemporary and historic collections were measured, as a proxy for the annual growth rate of exploited and protected populations. Hierarchical mixed models were used to partition growth variation within and among individuals and ascribe growth to intrinsic and extrinsic effects. The best model for the protected population indicated that the growth response of C. laticeps was poorer during years characterised by a high cumulative upwelling intensity, and better during years characterised by higher mean autumn sea surface temperatures. The exploited population growth chronology was too short to identify an extrinsic growth driver. The growth results again highlight the role of thermal variability in modulating the response of C. laticeps to its ambient environment and indicate that the predicted increases in upwelling frequency and intensity may constrain future growth rates of this species. A metabolic index (ϕ), representing the ratio of O2 supply to demand at various temperatures and oxygen concentrations, was estimated for exploited and protected populations of C. laticeps and used to predict future distribution responses. There was no difference in the laboratory calibrations of ϕ between populations, and all data was subsequently combined into a single piecewise (12 °C) calibrated ϕ model. To predict the distribution of C. laticeps, ϕ was projected across a high-resolution ocean model of the South African coastal zone, and a species distribution model implemented using the random forest algorithm and C. laticeps occurrence points. The future distribution of C. laticeps was estimated by predicting trained models across ocean model projections up to 2100. The best predictor of C. laticeps’ current distribution was minimum monthly ϕ and future predictions indicated only a slight range contraction on either edge of C. laticeps’ distribution by 2100. In order to provide policy makers, currently developing climate change management frameworks for South Africa’s ocean, with a usable output, the results of all research chapters were combined into a marine spatial model. The spatial model identified areas where C. laticeps is predicted to be resilient to climate change in terms of physiology, growth and distribution responses, which can then be prioritised for adaptation measures, such as spatial protection from exploitation. While these results are specific to C. laticeps, the methodology developed to identify areas of climate resilience has broad applications across taxa. From a global perspective, perhaps the most salient points to consider from this case study are the evidence of selective exploitation on physiological traits and the importance of environmental variability, rather than long-term mean climate changes, in affecting organism performance. These ideas are congruent with the current paradigm shift in how we think of the ocean, selective fisheries, and how they relate to organism climate resilience.
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A pilot wide-field VLBI survey of the GOODS-North field

  • Authors: Akoto-Danso, Alexander
  • Date: 2019
  • Subjects: Radio astronomy , Very long baseline interferometry , Radio interometers , Imaging systems in astronomy , Hubble Space Telescope (Spacecraft) -- Observations
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/72296 , vital:30027
  • Description: Very Long Baseline Interferometry (VLBI) has significant advantages in disentangling active galactic nuclei (AGN) from star formation, particularly at intermediate to high-redshift due to its high angular resolution and insensitivity to dust. Surveys using VLBI arrays are only just becoming practical over wide areas with numerous developments and innovations (such as multi-phase centre techniques) in observation and data analysis techniques. However, fully automated pipelines for VLBI data analysis are based on old software packages and are unable to incorporate new calibration and imaging algorithms. In this work, the researcher developed a pipeline for VLBI data analysis which integrates a recent wide-field imaging algorithm, RFI excision, and a purpose-built source finding algorithm specifically developed for the 64kx64k wide-field VLBI images. The researcher used this novel pipeline to process 6% (~ 9 arcmin2 of the total 160 arcmin2) of the data from the CANDELS GOODS- North extragalactic field at 1.6 GHz. The milli-arcsec scale images have an average rms of a ~ 10 uJy/beam. Forty four (44) candidate sources were detected, most of which are at sub-mJy flux densities, having brightness temperatures and luminosities of >5x105 K and >6x1021 W Hz-1 respectively. This work demonstrates that automated post-processing pipelines for wide-field, uniform sensitivity VLBI surveys are feasible and indeed made more efficient with new software, wide-field imaging algorithms and more purpose-built source- finders. This broadens the discovery space for future wide-field surveys with upcoming arrays such as the African VLBI Network (AVN), MeerKAT and the Square Kilometre Array (SKA).
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A platform for women’s experiences? a case of the hip hop scene in Grahamstown, Eastern Cape

  • Authors: Kabwato, Sasha Nyasha
  • Date: 2019
  • Subjects: Hip-hop -- South Africa -- Makhanda , Popular culture -- South Africa -- Makhanda , Rap musicians -- South Africa -- Makhanda , Musicians, Black -- South Africa -- Makhanda , Women musicians, Black -- South Africa -- Makhanda , Women, Black -- South Africa -- Makhanda -- Psychology
  • Language: English
  • Type: text , Thesis , Masters , MSocSc
  • Identifier: http://hdl.handle.net/10962/96503 , vital:31287
  • Description: The main aim of this research is to examine the hip hop scene in Grahamstown, Eastern Cape and whether hip hop can serve as a significant platform to discuss women’s lived experiences. This study also places focus on how female rappers construct their rap personas, as well as how they are perceived by their male counterparts. In order to understand the multifaceted viewpoints, it was necessary to interview both male and female hip hop artists. Eight interviews were conducted with eight young black rappers who are actively involved in the Grahamstown hip hop scene. It was found that hip hop, like any other art form, is a significant platform for women to express themselves, however gender constraints limit who is willing to listen to and promote their music. Male rappers advocate for women to talk about their stories, yet are more unlikely to listen because it does not relate to their struggles. In addition, there seem to be four specific tropes that female rappers choose to construct their identities from. Female rappers tend to create their personas around: Queen Mother, Fly Sista, Bitch with Attitude, and Lesbian. However, these categories are fluid and it was found that women navigate these categories depending on their audience and message they want to convey at a particular moment. Lastly, there is a split between Grahamstown West (Rhodes University) and Grahamstown East (township). University students are unlikely to perform in the township, and township residents rarely perform at organised events in Grahamstown West. In addition, Rhodes University students are more likely to feature on the university run radio station, rather than Radio Grahamstown, the local community radio.
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A return to common-sense: why ecology needs transcendental realism

  • Authors: Price, Leigh
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/390324 , vital:68538 , xlink:href="https://doi.org/10.1080/14767430.2019.1580178"
  • Description: Empirical realist ecologists, such as C. S. Holling, face significant methodological contradictions; for instance, they must cope with the problem that ecological models and theories of climate change, resilience and succession cannot make predictions in open systems. Generally, they respond to this problem by supplementing their empirical realism with transcendental idealism: they therefore say that their models are simply metaphorical or heuristic, that is, 'not true' in that they are not empirical. Thus, they explicitly deny an ontology for what their models are about. Nevertheless, in their practice, ecologists act as if their theories do have an ontology and thus tell us something truthful about the real world. This discrepancy leaves ecology vulnerable to unnecessary critique, such as that climate science is not real science. Transcendental realism offers a solution because it releases ecologists from the requirement to make predictions; but it does so without denying ontology. This provides several advantages to ecologists.
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