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An investigation into the development of knowledge and strategies for the teaching of visual literacy in under-resourced Eastern Cape schools

  • Authors: Mbelani, Madeyandile
  • Date: 2014
  • Subjects: Uncatalogued
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/64401 , vital:28540
  • Description: This thesis reports on a multiple case study PhD project that aimed to investigate meaningful and critical development of knowledge and strategies to teach visual literacy, a component of English First Additional Language (FAL) in six under-resourced schools of the Eastern Cape of South Africa. The study begins by locating visual literacy within a broad framework of literacy as a social practice, and discusses its importance. Further, it discusses complexities of making sense of and teaching visual literacy, especially for the majority of in-service teachers who experienced visual literacy neither as learners nor as teacher trainees. The gap between the curriculum and teachers’ classroom practices is what triggered this study to adopt a transformative paradigm. The main research question is, “How can teacher professional development in English Language Teaching advance in-service teachers’ knowledge of and strategies for meaningful and critical teaching and learning of visual literacy?” To respond to this question, I drew on cultural historical activity theory (CHAT) and critical realism (CR) to design four phases of this study that incorporated the seven stages of an expansive learning cycle. These phases focussed on exploring and expanding teachers’ sense making and teaching of visual literacy. I collected data through interviews, document analysis, videoed lessons and change laboratory (CL) workshops. I designed a data analysis tool that brought together CHAT, CR, multimodal social semiotics, critical discourse analysis and pedagogical discourse to make sense of the data. Through a process of reflexivity, the study illuminated layers of factors that constrained meaningful and critical teaching of visual literacy in the empirical, the actual and the real domains of reality. These factors include teachers’ unconscious reproduction of discourses of domination, their intolerance of diverse cultural discourses, resistance to curriculum change, and the fact that they are comfortable with the status quo. I brought these factors to CL workshops for expansive learning. The study contributes in-depth insight into English FAL in-service teacher development in the area of visual literacy. By locating the study within meaning making and teaching of visual literacy, it was possible to interrogate access, diversity, domination and design in teachers’ classroom practices. As a result of this study participants were made aware of the extent to which these factors enabled or hindered meaningful and critical teaching. Participants repositioned themselves as subjects of the activity system, thereby mobilising their agency to take control of the structures and cultures that condition their teaching.
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An investigation into the nature of grade 4 learners’ evolving mathematics learning dispositions: a case study of 3 learners participating in an after school mathematics club

  • Authors: Hewana, Diliza Ronald
  • Date: 2014
  • Subjects: Mathematics -- Study and teaching (Elementary) -- Case studies , Mathematics -- Study and teaching (Elementary) -- Psychological aspects , After-school programs -- South Africa -- Grahamstown , Students -- Attitudes -- Case studies , Education, Elementary -- South Africa -- Grahamstown
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1983 , http://hdl.handle.net/10962/d1013140
  • Description: Through a qualitative case study approach this research investigated the nature of three Grade 4 learners’ mathematical learning dispositions. It further explored how these dispositions evolve within the context of their participation in a weekly after school mathematics club over time. Of particular significance the research drew on the dispositional frameworks of Kilpatrick, Swafford and Findell’s (2001) and Carr & Claxton (2002) and pointed to ways in which these framework can be usefully brought together to provide a richer picture of learning dispositions. Kilpatrick, Swafford and Findell’s (2001) framework of mathematical proficiency involves five interrelated strands of which productive disposition is the fifth strand and largely underresearched (Graven, 2012). This strand is defined as ‘the tendency to see sense in mathematics, to perceive it as both useful and worthwhile, to believe that steady effort in learning mathematics pays off, and to see oneself as an effective learner and doer of mathematics’ (Kilpatrick, Swafford and Findell, 2001, p. 131). Carr & Claxton (2002) similarly argue for the importance of learning dispositions and point to the importance of resilience, playfulness and resourcefulness as three key indicators. The research outlines findings of the three case study learners in terms of data obtained from a questionnaire and interview about students’ learning dispositions. The interview asked learners various questions including for example, complete the sentence ‘Maths is…’, describe an effective learner of mathematics and say what you do if you don’t know an answer. The instrument was first administered orally and learners were asked to write their answers (in May 2012) and a year later it was administered as an interview by the club facilitator (in May 2013). While there is the limitation of comparison due to the different ways in which learners responded in 2012 (written) and 2013 (oral) the shifting nature of responses in certain respects provides some indication of shifts towards increasingly productive dispositions. Additionally the research analysed detailed transcripts of video recordings of several club sessions over a five-month period. Findings suggest ways of extending dispositional frameworks and that learners have restricted dispositions particularly in terms of sense making and resourcefulness across time. The findings also suggest shifts in dispositions over time especially in terms of seeing steady effort as paying off.
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An investigation into understanding of academic literacies of students registered in Early Childhood Development courses

  • Authors: Hackmack, Karin Erna
  • Date: 2014
  • Subjects: Academic writing -- Study and teaching -- South Africa -- Grahamstown , Discourse analysis , Information literacy -- Study and teaching (Higher) , Information literacy -- Social aspects , Early childhood education -- Study and teaching (Higher) -- South Africa -- Grahamstown , Education -- Study and teaching (Higher) -- South Africa -- Grahamstown
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1996 , http://hdl.handle.net/10962/d1013548
  • Description: Purpose and research questions- This research was based on students enrolled on courses at Rhodes University's Centre for Social Development, an Institute delivering Early Childhood Development courses in the Grahamstown area. Having provided the students with access to a career path and its courses, it was imperative to assist the students to develop a standard of academic literacy comparable to that of in-service education students, in the Intermediate and Senior Phases. This study was influenced by Gee's (2004) definition of literacy as 'mastery over a discourse'. Gee (1990) termed discourse as the socially accepted way of thinking, believing and being. The study therefore investigated the enablers which assisted students to produce academic texts. This was achieved by finding out how the students and the course facilitators construct academic literacy; in other words what their discourses were regarding academic literacy. In order to ascertain this information, the students and the course facilitators were asked what reading and writing the students had done prior to enrolling on the course, what they had brought to the course, what the students and the course facilitators thought comprised a successful academic assignment, and how the students were supported in their academic literacy during the course. Data was gathered through interviews with both students and course facilitators, analysis of course assignments, and assessment reports written by the course facilitators. This data was analysed, looking for discourses on similarities and contradictions. Critical Discourse analysis was used to investigate the discourses that the course facilitators and students were using. Findings: It was evident from the data that the autonomous view of literacy was predominantly used. The course facilitators and, to a limited extent, the students, saw literacy as a set of technical skills that needed to be mastered. The students and course facilitators did not take into account that literacy is a social practice, and that literacy occurs within a particular social context and cultural context. The course facilitators tended to hold a deficit discourse related to the perception of inferior education under Bantu Education, which was seen as an inhibiting factor to academic literacy and academic success. The discourse of second language was also an issue that both the course facilitators and the students noted which prevented students' academic literacy. Christie's (1985) Received Tradition of Literacy, which focused on the forms and functions of literacy, was a discourse that both the students and the course facilitators ascribed to. Conclusions and recommendations: The course facilitators' and students' discourses were very similar, both being embedded within the autonomous and deficit models of literacy. It is recommended that course facilitators become cognisant with the models of academic literacy and that they become aware of the various discourses evident on the course and articulate these discourses for themselves. Furthermore they should assist the students by clearly articulating and unpacking the course requirements regarding academic literary.
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An investigation into XSets of primitive behaviours for emergent behaviour in stigmergic and message passing antlike agents

  • Authors: Chibaya, Colin
  • Date: 2014
  • Subjects: Ants -- Behavior -- Computer programs , Insects -- Behavior -- Computer programs , Ant communities -- Behavior , Insect societies
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4698 , http://hdl.handle.net/10962/d1012965
  • Description: Ants are fascinating creatures - not so much because they are intelligent on their own, but because as a group they display compelling emergent behaviour (the extent to which one observes features in a swarm which cannot be traced back to the actions of swarm members). What does each swarm member do which allows deliberate engineering of emergent behaviour? We investigate the development of a language for programming swarms of ant agents towards desired emergent behaviour. Five aspects of stigmergic (pheromone sensitive computational devices in which a non-symbolic form of communication that is indirectly mediated via the environment arises) and message passing ant agents (computational devices which rely on implicit communication spaces in which direction vectors are shared one-on-one) are studied. First, we investigate the primitive behaviours which characterize ant agents' discrete actions at individual levels. Ten such primitive behaviours are identified as candidate building blocks of the ant agent language sought. We then study mechanisms in which primitive behaviours are put together into XSets (collection of primitive behaviours, parameter values, and meta information which spells out how and when primitive behaviours are used). Various permutations of XSets are possible which define the search space for best performer XSets for particular tasks. Genetic programming principles are proposed as a search strategy for best performer XSets that would allow particular emergent behaviour to occur. XSets in the search space are evolved over various genetic generations and tested for abilities to allow path finding (as proof of concept). XSets are ranked according to the indices of merit (fitness measures which indicate how well XSets allow particular emergent behaviour to occur) they achieve. Best performer XSets for the path finding task are identifed and reported. We validate the results yield when best performer XSets are used with regard to normality, correlation, similarities in variation, and similarities between mean performances over time. Commonly, the simulation results yield pass most statistical tests. The last aspect we study is the application of best performer XSets to different problem tasks. Five experiments are administered in this regard. The first experiment assesses XSets' abilities to allow multiple targets location (ant agents' abilities to locate continuous regions of targets), and found out that best performer XSets are problem independent. However both categories of XSets are sensitive to changes in agent density. We test the influences of individual primitive behaviours and the effects of the sequences of primitive behaviours to the indices of merit of XSets and found out that most primitive behaviours are indispensable, especially when specific sequences are prescribed. The effects of pheromone dissipation to the indices of merit of stigmergic XSets are also scrutinized. Precisely, dissipation is not causal. Rather, it enhances convergence. Overall, this work successfully identify the discrete primitive behaviours of stigmergic and message passing ant-like devices. It successfully put these primitive behaviours together into XSets which characterize a language for programming ant-like devices towards desired emergent behaviour. This XSets approach is a new ant language representation with which a wider domain of emergent tasks can be resolved.
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An investigation of a mathematics recovery programme for multiplicative reasoning to a group of learners in the South African context : a case study approach

An investigation of parameter relationships in a high-speed digital multimedia environment

  • Authors: Chigwamba, Nyasha
  • Date: 2014
  • Subjects: Multimedia communications , Digital communications , Local area networks (Computer networks) , Computer network architectures , Computer network protocols , Computer sound processing , Sound -- Recording and reproducing -- Digital techniques
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4725 , http://hdl.handle.net/10962/d1021153
  • Description: With the rapid adoption of multimedia network technologies, a number of companies and standards bodies are introducing technologies that enhance user experience in networked multimedia environments. These technologies focus on device discovery, connection management, control, and monitoring. This study focused on control and monitoring. Multimedia networks make it possible for devices that are part of the same network to reside in different physical locations. These devices contain parameters that are used to control particular features, such as speaker volume, bass, amplifier gain, and video resolution. It is often necessary for changes in one parameter to affect other parameters, such as a synchronised change between volume and bass parameters, or collective control of multiple parameters. Thus, relationships are required between the parameters. In addition, some devices contain parameters, such as voltage, temperature, and audio level, that require constant monitoring to enable corrective action when thresholds are exceeded. Therefore, a mechanism for monitoring networked devices is required. This thesis proposes relationships that are essential for the proper functioning of a multimedia network and that should, therefore, be incorporated in standard form into a protocol, such that all devices can depend on them. Implementation mechanisms for these relationships were created. Parameter grouping and monitoring capabilities within mixing console implementations and existing control protocols were reviewed. A number of requirements for parameter grouping and monitoring were derived from this review. These requirements include a formal classification of relationship types, the ability to create relationships between parameters with different underlying value units, the ability to create relationships between parameters residing on different devices on a network, and the use of an event-driven mechanism for parameter monitoring. These requirements were the criteria used to govern the implementation mechanisms that were created as part of this study. Parameter grouping and monitoring mechanisms were implemented for the XFN protocol. The mechanisms implemented fulfil the requirements derived from the review of capabilities of mixing consoles and existing control protocols. The formal classification of relationship types was implemented within XFN parameters using lists that keep track of the relationships between each XFN parameter and other XFN parameters that reside on the same device or on other devices on the network. A common value unit, known as the global unit, was defined for use as the value format within value update messages between XFN parameters that have relationships. Mapping tables were used to translate the global unit values to application-specific (universal) units, such as decibels (dB). A mechanism for bulk parameter retrieval within the XFN protocol was augmented to produce an event-driven mechanism for parameter monitoring. These implementation mechanisms were applied to an XFN-protocol-compliant graphical control application to demonstrate their usage within an end user context. At the time of this study, the XFN protocol was undergoing standardisation within the Audio Engineering Society. The AES-64 standard has now been approved. Most of the implementation mechanisms resulting from this study have been incorporated into this standard.
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An investigation of protocol command translation as a means to enable interoperability between networked audio devices

  • Authors: Igumbor, Osedum Peter
  • Date: 2014
  • Subjects: Streaming audio Data transmission systems Computer network protocols Computer networks -- Management Command languages (Computer science)
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4689 , http://hdl.handle.net/10962/d1011128
  • Description: Digital audio networks allow multiple channels of audio to be streamed between devices. This eliminates the need for many different cables to route audio between devices. An added advantage of digital audio networks is the ability to configure and control the networked devices from a common control point. Common control of networked devices enables a sound engineer to establish and destroy audio stream connections between networked devices that are distances apart. On a digital audio network, an audio transport technology enables the exchange of data streams. Typically, an audio transport technology is capable of transporting both control messages and audio data streams. There exist a number of audio transport technologies. Some of these technologies implement data transport by exchanging OSI/ISO layer 2 data frames, while others transport data within OSI/ISO layer 3 packets. There are some approaches to achieving interoperability between devices that utilize different audio transport technologies. A digital audio device typically implements an audio control protocol, which enables it process configuration and control messages from a remote controller. An audio control protocol also defines the structure of the messages that are exchanged between compliant devices. There are currently a wide range of audio control protocols. Some audio control protocols utilize layer 3 audio transport technology, while others utilize layer 2 audio transport technology. An audio device can only communicate with other devices that implement the same control protocol, irrespective of a common transport technology that connects the devices. The existence of different audio control protocols among devices on a network results in a situation where the devices are unable to communicate with each other. Furthermore, a single control application is unable to establish or destroy audio stream connections between the networked devices, since they implement different control protocols. When an audio engineer is designing an audio network installation, this interoperability challenge restricts the choice of devices that can be included. Even when audio transport interoperability has been achieved, common control of the devices remains a challenge. This research investigates protocol command translation as a means to enable interoperability between networked audio devices that implement different audio control protocols. It proposes the use of a command translator that is capable of receiving messages conforming to one protocol from any of the networked devices, translating the received message to conform to a different control protocol, then transmitting the translated message to the intended target which understands the translated protocol message. In so doing, the command translator enables common control of the networked devices, since a control application is able to configure and control devices that conform to different protocols by utilizing the command translator to perform appropriate protocol translation.
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An investigation of stakeholder participation and learning in two schools within the Seychelles Eco-School programme

  • Authors: Emilie, Shane Antonio
  • Date: 2014
  • Subjects: Environmental education -- Seychelles Schools -- Environmental aspects -- Seychelles Education, Primary -- Parent participation -- Seychelles Education, Secondary -- Parent participation -- Seychelles Student participation in administration -- Education (Primary) -- Seychelles Student participation in administration -- Education (Secondary) -- Seychelles Student participation in curriculum planning -- Education (Primary) -- Seychelles Student participation in curriculum planning -- Education (Secondary) -- Seychelles Education, Primary -- Seychelles Education, Secondary -- Seychelles
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1969 , http://hdl.handle.net/10962/d1011961
  • Description: The aim of this study was to investigate stakeholder participation and learning in the Seychelles Eco-School programme within a primary school context and a secondary school context. Findings from each Eco-School have been presented in two case studies with the goal to explore and describe how teachers, students, parents and organizations are participating and learning in the Eco-School programme. Six elements of school community were used to deepen understanding of the participatory and learning processes in each Eco-School, namely, leadership, management and administration, curriculum planning, teaching and learning, resource use and management, management of physical surrounds of the school and networks and partnerships. Some of the contextual variables in each Eco-School that were constraining and enabling stakeholder participation and learning in the programme have also been explored within this study. Data in this study was generated from historical documents analysed, semi-structured interviews, focus group discussions and field notes. Data was also generated from questionnaires completed by organizations involved in the programme at each Eco- School. Data was analysed in two phases, the first phase involved reading across data generated from the methods mentioned above to organize the data under broad themes in relation to the elements of school community. The second phase of analysis involved the use of the conceptual framework of situating learning in a community of practice to interpret and discuss the participatory and learning processes across the two cases. The study showed that in each Eco-School there is a community of practice with the active involvement of teachers and students and the occasional involvement of parents and organizations. Students and adults are learning as they engage together in classroom and field-work interactions, environmental projects, environmental activities to commemorate environmental theme days, environmental campaigns and co-curricular activities through the practices of each Eco-School community. It was also discovered that students and adults are making different contributions in the Eco-School community based on their level of participation in the programme. It is hoped that the findings in this research contribute information regarding community participation in environmental education programmes like the Seychelles Eco-School programme. In addition, findings will inform the Seychelles Government and its partners to consider the possibility of enhancing school and community partnerships to respond to some of the challenges of participation and learning in the Eco-School programme.
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An investigation of the intention to leave or stay of health care professionals at St. Andrews Hospital

  • Authors: Amanambu, Rochelle Aneeta
  • Date: 2014
  • Subjects: Medical personnel -- Job satisfaction -- South Africa -- Eastern Cape -- Case studies Medical personnel -- Job stress -- South Africa -- Eastern Cape -- Case studies Hospitals -- South Africa -- Eastern Cape -- Administration Hospitals -- Medical staff -- South Africa -- Eastern Cape Hospitals -- Officials and employees -- South Africa -- Eastern Cape -- Turnover Health services administration -- South Africa -- Eastern Cape Health planning -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:823 , http://hdl.handle.net/10962/d1011091
  • Description: Background: The demand for and retention of talent worldwide is aggravated by revolutionary trends that include global competition, demographic changes and technological advances. In South Africa this phenomenon according to Frost (2002) is further challenged by the emigration of skilled people; the relative scarcity of specialist and managerial employees; employment equity and affirmative action procedures. But the development of strategies first requires an understanding of the factors which influence decisions to leave or stay particularly in rural and remote areas. St. Andrews Hospital is a rural district hospital in Ugu District, KZN. Its remoteness from urban areas and the lack of resources contributes towards challenges of attracting and retaining health care professionals to the area. It is the aim of this study to identify the ten most prevalent turnover and retention factors in a rural district hospital with the intention of making recommendations towards strategies to mitigate turnover and improve retention of health care professionals. This study will not only serve the local Human Resource Department but may also be used to inform district and provincial policies as well as departments’ decisions in the design or the review of current retention strategies aimed at reducing turnover. Method: The survey method was used to collect the primary data by distribution of self-administered questionnaires to Health Care Professionals at St. Andrews Hospital. Of the one hundred and fifty questionnaires distributed, one hundred and seven were returned (71% response rate) and formed the basis of the study. Results: Based on the impact scores, the top three turnover factors identified were, the way the organisation is led by top management (0.934); the size of the workload (0.862); and the way problems are dealt with by managers in the organisation (0.817). No statistically significant relationships were found between turnover factors and biographical variable. Availability of quality health services was ranked as the external factor that had the highest influence (78%) on turnover, while geographical location was ranked the lowest. The main reason given by respondents for leaving their previous employment was promotion, followed by distance and personal/family reasons. The top three retention factors identified from the impact scores were the quality of relationships with colleagues (1.698); the amount of support received from managers and colleagues (1.484); and the level of engagement and involvement with the job (1.390). This demonstrates that the salary package often thought to be a first priority factor Mobley, Horner and Hollingsworth (1978); Mobley (1982) and Herzberg (2003) is far less of a determining factor at St. Andrews Hospital than management support, job involvement and person-organisation fit as well as the social relationships formed in the workplace. A positive relationship was found between leadership and job dimension factors at the 1% level of significance. This supports the strong social bond (person-organisation fit) formed in the work environment between management and colleagues that supports retention and increases level of commitment. An important result of the study was that 46% of the respondents were thinking of leaving the town within the year while 29% were considering resigning from St. Andrews Hospital within the year. Conclusion: The results reveal a complex interaction of factors impacting on turnover and retention. The Human Resource Management function has a pivotal role to play in improving its ability to attract and retain professionals through developing comprehensive strategies based on external and internal and environmental factors. The study conveys to the St. Andrews Hospital management that turnover and retention factors are unique to the location and the working environment and differs amongst Health Care Professionals – this should be deliberated on when formulating Hospital Human Resource retention policies.
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An investigation of the potential anti-diabetic (insulinomimetic) activity of anti-oxidant compounds derived from Sargassum heterophyllum

  • Authors: Nyambe, Mutenta Nsokolo
  • Date: 2014
  • Subjects: Sargassum , Diabetes -- Chemotherapy , Diabetes -- Africa , Antioxidants -- Therapeutic use , Marine algae , Endemic plants -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3874 , http://hdl.handle.net/10962/d1021020
  • Description: In Africa, non-communicable diseases such as diabetes mellitus have been generally neglected. This problem has worsened over the years owing to continuous threats from infectious diseases such as HIV/AIDS, tuberculosis and malaria. Despite this, statistics have shown that by 2030, the African region will have the highest proportional increase in diabetes prevalence. Over 80% of all diabetic deaths occur in developing countries probably not only due to poor equity of access to medication but also due to limited efficacy and side effects associated with the commonly available anti-diabetic agents. Therefore, this creates the desperate need for the development of new anti-diabetic agents that are more efficacious and can be sourced from within the continent. With oxidative stress as a suggested mechanism underlying the cause of diabetes mellitus and diabetic complications, the discovery of natural anti-oxidants that prevent free radical mediated damage is important for developing new treatment strategies. Marine algae have been identified as good sources for natural anti-oxidants. Unfortunately, very few studies have embarked on the discovery of marine-derived anti-oxidant compounds with potential anti-diabetic activity. In this project, we investigated the potential anti-oxidant activity of the South African endemic algae Stypopodium multipartitum, Dictyopterus ligulata, Cystophora fibriosa, Bifurcariopsis capensis, Sargassum sp. and Sargassum heterophyllum. From these studies, Sargassum heterophyllum yielded prenylated compounds, the main compound being sargahydroquinoic acid (3.6) and the carotenoid metabolite fucoxanthin (3.8), which are in part responsible for the radical scavenging activity of the crude extract. Sargahydroquinoic acid (3.6) and fucoxanthin (3.8) also exhibited significant anti-inflammatory activity. Sargaquinoic acid (3.1), sargachromenoic acid (3.9) and sarganaphthoquinoic acid (3.10) were then semi-synthesized from sargahydroquinoic acid (3.6) and their in-vitro cytotoxicity profiles evaluated using Chang Liver, HT-29, Caco-2 and 3T3-L1 cell lines prior to antidiabetic testing. From the semi-synthetic derivatives, sargachromenoic acid (3.9) exhibited the most potent anti-oxidant activity (IC₅₀ = 6.99 μg/mL). After the evaluation of antidiabetic activity using 3T3-L1 preadipocyte differentiation, sarganaphthoquinoic acid (3.10) showed the most potent insulinomimetic activity at 1.19 μM by inducing a PPARγ response similar to that of rosiglitazone at 1 μM.
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An investigation of the role of mitochondrial STAT3 and modulation of Reactive Oxygen Species in adipocyte differentiation

  • Authors: Kramer, Adam Hildyard
  • Date: 2014
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/54632 , vital:26595
  • Description: Stem cells have the ability to differentiate into a myriad of different cell types. The understanding of the differentiation process is of paramount importance if we are to use these cells in the lab as well as in therapeutics. Here, the levels and localization of the signal transducer and activator of transcription 3 (STAT3), with particular attention focused on the mitochondrial serine 727 phosphorylated form of STAT3 (pSTAT3S727) during differentiation, was investigated. Using the murine preadipocyte progenitor cell line 3T3-L1, as well as adipose derived human mesenchymal stem cells (HMSC-ad) as differentiation models, the relative levels of Reactive Oxygen Species (ROS) and the levels and localization of STAT3 were investigated during the differentiation process. ROS is known to play an important signalling role during differentiation and is well reported during the events of adipogenesis. ROS are generated as a by-product in the Electron Transport Chain (ETC), and it has recently been reported that pSTAT3S727 plays an important role at complex I of the ETC. Various techniques including fluorescence confocal microscopy, flow cytometry and Western blots were utilized to investigate the non-canonical role STAT3 plays during adipogenesis. Mitochondrial isolations were performed to investigate the levels of STAT3 in the mitochondria during differentiation. Further to this, an impedance based real time differentiation assay was developed using the xCELLigence Real Time Cell Analyser to monitor differentiation and the affects various compounds, including a STAT3 inhibitor, have on differentiation. Results indicate that upon induction of differentiation, levels of mitochondrial pSTAT3S727 dramatically decrease and leave the mitochondria. This corresponds to increasing levels of ROS. The canonical active form of STAT3 following phosphorylation on tyrosine 705 (pSTAT3Y705) was found to decrease and lose its nuclear localization. These initial results indicate that STAT3 plays an important non-canonical role in the mitochondria during differentiation.
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An investigation of the XMOS XSl architecture as a platform for development of audio control standards

  • Authors: Dibley, James
  • Date: 2014
  • Subjects: Microcontrollers -- Research , Streaming audio -- Standards -- Research , Computer sound processing -- Research , Computer network protocols -- Standards -- Research , Communication -- Technological innovations -- Research
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4694 , http://hdl.handle.net/10962/d1011789 , Microcontrollers -- Research , Streaming audio -- Standards -- Research , Computer sound processing -- Research , Computer network protocols -- Standards -- Research , Communication -- Technological innovations -- Research
  • Description: This thesis investigates the feasiblity of using a new microcontroller architecture, the XMOS XS1, in the research and development of control standards for audio distribution networks. This investigation is conducted in the context of an emerging audio distribution network standard, Ethernet Audio/Video Bridging (`Ethernet AVB'), and an emerging audio control standard, AES-64. The thesis describes these emerging standards, the XMOS XS1 architecture (including its associated programming language, XC), and the open-source implementation of an Ethernet AVB streaming audio device based on the XMOS XS1 architecture. It is shown how the XMOS XS1 architecture and its associated features, focusing on the XC language's mechanisms for concurrency, event-driven programming, and integration of C software modules, enable a powerful implementation of the AES-64 control standard. Feasibility is demonstrated by the implementation of an AES-64 protocol stack and its integration into an XMOS XS1-based Ethernet AVB streaming audio device, providing control of Ethernet AVB features and audio hardware, as well as implementations of advanced AES-64 control mechanisms. It is demonstrated that the XMOS XS1 architecture is a compelling platform for the development of audio control standards, and has enabled the implementation of AES-64 connection management and control over standards-compliant Ethernet AVB streaming audio devices where no such implementation previously existed. The research additionally describes a linear design method for applications based on the XMOS XS1 architecture, and provides a baseline implementation reference for the AES-64 control standard where none previously existed.
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An investigation of Wikipedia translation as an additive pedagogy for Oshikwanyama first language learning

  • Authors: Hautemo, Aletta Mweneni
  • Date: 2014
  • Subjects: Kuanyama language -- Study and teaching (Secondary) -- Computer-assisted instruction , Kuanyama language -- Machine translating -- Namibia , Language and languages -- Study and teaching (Secondary) -- Computer-assisted instruction , Computer-assisted instruction -- Study and teaching (Secondary) -- Namibia , Information technology -- Study and teaching (Secondary) -- Namibia , Educational technology -- Namibia , Wikipedia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1982 , http://hdl.handle.net/10962/d1013139
  • Description: The integration of Information and Communication Technology in the indigenous language classroom lags behind compared to other subjects. In many ways, indigenous language teachers find it difficult and to some extent, impossible to integrate ICT into their classroom activities. The focus of this study is to explore the ways in which ICT could be used as a learning tool in an Oshikwanyama First Language classroom. I investigated the use of Wikipedia translation as an additional teaching and learning tool. I concentrated on the impact that ICT tools have on learning, and the motivation it has on learners to learn Oshikwanyama. This qualitative case study was conducted in an urban school in northern Namibia. The adoption of ICT at the school is good as there is a full-fledged computer lab with unlimited wireless internet access. This was a requirement for the project to enable the participants to work online. I purposefully chose higher-level learners (Secondary phase) for this study. I conducted a survey with them on their access to and use of ICT devices in their daily lives, and thereafter conducted a basic computer workshop and a Wikipedia translation project with them. My research findings show that although the use of ICT is part of the learners’ lives, most of the communication through ICT devices is done in English not Oshikwanyama. Wikipedia translation offers a stimulating learning platform for learners to learn Oshikwanyama and English at the same time and this improved their performance in both languages. Furthermore, the Wikipedia translation, which was done collaboratively, gave learners the confidence to work with other learners to create knowledge. Lastly, Wikipedia translation motivates learners to learn Oshikwanyama and use it in their daily ICT interaction.
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Analysis of the interaction of Hsp90 with the extracellular matrix protein fibronectin (FN)

  • Authors: Hunter, Morgan Campbell
  • Date: 2014
  • Subjects: Heat shock proteins , Fibronectins , Extracellular matrix proteins , Breast -- Cancer
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4170 , http://hdl.handle.net/10962/d1020960
  • Description: Mounting evidence suggests that Hsp90 is present and functionally active in the extracellular space. The biological function of extracellular Hsp90 (eHsp90) remains relatively uncharacterized compared to that of intracellular Hsp90. eHsp90 has been shown to interact with a finite number of extracellular proteins, however, despite the identification of eHsp90 interacting proteins, the function of eHsp90 in these complexes is unknown. Several reports suggest a role for eHsp90α in cell migration and invasion. Reported targets for eHsp90 stimulated cell migration include MMPs, LRP-1, tyrosine kinase receptors and possible others unidentified. Limited studies report a role for eHsp90β. Recently, Hsp90α and Hsp90β were isolated in a complex containing fibronectin (FN) on the surface of MDA-MB-231 breast cancer cells. Herein, we report direct binding of Hsp90α and Hsp90β to FN using a solid phase binding assay and surface plasmon resonance (SPR) spectroscopy. SPR spectroscopy showed that Hsp90β bound the 70 kDa amino-terminal fragment of FN (FN70), but that binding of FN to Hsp90β was not limited to FN70. Confocal microscopy showed regions of colocalization of Hsp90 with extracellular FN matrix fibrils in Hs578T breast cancer cell lines. Treatment of Hs578T breast cancer cells with novobiocin (an Hsp90 inhibitor) and an LRP-1 blocking antibody resulted in a loss of FN matrix and FN endocytosis (novobiocin treated). Addition of exogenous Hsp90β was able to recover such effect after both treatments. FN was shown to colocalize with intracellular LRP-1 in novobiocin treated Hs578T cells. Immunoprecipitation of an LRP-1 containing complex showed the presence of Hsp90 and 70 and 120+ kDa FN fragments. Treatment of Hs578T cells with novobiocin increased the level of FN120+ bound in LRP-1 immunoprecipitate. Exogenous Hsp90β decreased the level of low and high molecular weight FN fragments in a complex with LRP-1, despite the fact that higher levels of lower molecular weight FN fragments were detected in this cell lysate compared to the other treatments. We report FN as a novel interacting protein of eHsp90. Taken together, we provide evidence for a direct role of eHsp90β in FN matrix remodeling. We suggest that Hsp90 plays a direct role in FN matrix dynamics through interaction with FN and LRP-1. The identification of FN as a novel interacting protein of eHsp90 suggests a role for Hsp90 in FN matrix remodeling, which is important for a number of fundamental cellular processes including cell migration and metastasis.
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Analysis of transcription factor binding specificity using ChIP-seq data.

  • Authors: Kibet, Caleb Kipkurui
  • Date: 2014
  • Subjects: Transcription factors , Chronic myeloid leukemia , Antioncogenes , Cancer cells -- Growth -- Regulation
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4115 , http://hdl.handle.net/10962/d1013131
  • Description: Transcription factors (TFs) are key regulators of gene expression whose failure has been implicated in many diseases, including cancer. They bind at various sites at different specificity depending on the prevailing cellular conditions, disease, development stage or environmental conditions of the cell. TF binding specificity is how well a TF distinguishes functional sites from potential non-functional sites to form a useful regulatory network. Owing to its role in diseases, various techniques have been used to determine TF binding specificity in vitro and in vivo, including chromatin immuno-precipitation followed by massively parallel sequencing (ChIP-seq). ChIP-seq is an in vivo technique that considers how the chromatin landscape affects TF binding. Motif enrichment analysis (MEA) tools are used to identify motifs that are over-represented in ChIP-seq peak regions. One such tool, CentriMo, finds over-represented motifs at the center since peak calling software are biased to declaring binding regions centered at the TF binding site. In this study, we investigate the use of CentriMo and other MEA tools to determine the difference in motif enrichment attributed presence of Chronic Myeloid leukemia (CML)), treatment with Interferon (IFN) and Dexamethasone (DEX) compared to control based on Fisher’s exact test; using uniform peaks ChIP-seq data generated by the ENCODE consortium. CentriMo proved to be capable. We observed differential motif enrichment of TFs with tumor promoter activity: YY1, CEBPA, Egr1, Cmyc family, Gata1 and JunD in K562 while Stat1, Irf1, and Runx1 in Gm12878. Enrichment of CTCF in Gm12878 with YY1 as the immuno-precipitated (ChIP-ed) factor and the presence of significant spacing (SpaMo analysis) of CTCF and YY1 in Gm12878 but not in K562 could show that CTCF, as a repressor, helps in maintaining the required YY1 level in a normal cell line. IFN might reduce Cmyc and the Jun family of TFs binding via the repressive action of CTCF and E2f2. We also show that the concentration of DEX treatment affects motif enrichment with 50nm being an optimum concentration for Gr binding by maintaining open chromatin via AP1 TF. This study has demonstrated the usefulness of CentriMo for TF binding specificity analysis.
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Antimicrobial properties and isotope investigations of South African honey

  • Authors: Khan, F , Hill, Jaclyn M , Kaehler, Sven , Allsopp, M , van Vuuren, S
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/444539 , vital:74249 , https://doi.org/10.1111/jam.12533
  • Description: The therapeutic potential of honey for the treatment of wound infections is well documented. However, South African (SA) honey has been poorly explored as an antimicrobial agent and given the well‐established antimicrobial properties of the indigenous plant species from SA, there is the potential that honey from this geographical region may exhibit noteworthy anti‐infective properties. In this study, the antimicrobial properties of 42 SA honey samples were determined.
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Application of carbon black and iron phthalocyanine composites in bioelectricity production at a brewery wastewater fed microbial fuel cell

  • Authors: Mshoperi, Edith , Fogel, Ronen , Limson, Janice L
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/431050 , vital:72740 , xlink:href="https://doi.org/10.1016/j.electacta.2013.11.01"
  • Description: Aerobic cathode microbial fuel cells (MFCs) have been widely researched to provide bioremediation of wastewaters, coupled to sustainable energy production. In order to effectively accomplish this aim, suitable catalysts and catalyst supports for oxygen reduction reaction (ORR) are required. While iron phthaloycanine (FePc), supported on multi-walled carbon nanotubes has previously been studied for this function, cost of industrial production may hinder this. Importantly, this study examines the use of several available grades of carbon black for their relative suitability to perform as supports for FePc in MFC formats. Voltammetric studies showed that the different grades of carbon black provided varying lowering of the ORR overpotential, between ∼160 and ∼270 mV relative to unmodified GCEs, and an optimum grade (N326) was selected for further study. Carbon black/FePC composite electrodes exhibited comparable lowering of the ORR overpotential (606 mV) to potentials previously reported to nanotube/FePc composites (620 mV), as well as lowered charge-transfer resistance compared to electrodes solely modified with FePc. When applied as cathode modifiers in dual chambered MFCs utilising Enterobacter cloacae, the combined use of carbon black and FePc provided greater power densities than either alone; composite electrodes obtaining ∼400% power density, compared to unmodified electrodes. Modification of the anode with carbon black further increased power density, generating power densities an order of magnitude larger than those obtained at unmodified electrodes. The ability of beer brewery waste water (BBWW) to generate power at these modified surfaces yielded permissible power densities (∼40% that of reinforced clostridial media). Differences observed, in particular under agitation, are attributed to variations in nutrient content and nutrient complexity, between the two fuel substrates.
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Applications of lead phthalocyanines embedded in electrospun fibers for the photoinactivation of Escherichia coli in water

  • Authors: Osifeko, Olawale L , Nyokong, Tebello
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/189898 , vital:44945 , xlink:href="https://doi.org/10.1016/j.dyepig.2014.05.010"
  • Description: Lead (II) pyridyloxyphthalocyanine (PbTpyPc) and its quaternized form (PbTepyPc) were synthesized and the photophysical behavior examined. Low fluorescence quantum yields (ΦF) of 0.01 and 0.02 were observed for PbTepyPc and PbTpyPc, respectively. The singlet oxygen quantum yields (ΦΔ) were 0.60 and 0.68, for PbTepyPc and PbTpyPc, respectively using DPBF as a quencher in DMF. Singlet oxygen production of the embedded sensitizers in electrospun fiber were quantified using ADMA and were found to be ΦΔ = 0.41 and ΦΔ = 0.21 for PbTepyPc and PbTpyPc, respectively. Photodynamic inactivation of Escherichia coli (E. coli) with the quaternized photosensitizer at 5 μM, totally inactivated the E. coli (with log CFU = 10 decrease). Only 0.4 log CFU decrease was obtained with PbTpyPc. The embedded non-quaternized photosensitizer (PbTpyPc) was less active on the gram negative bacteria but the quaternized photosensitizer (PbTepyPc) was effective towards inactivation of E. coli.
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Applications of lead phthalocyanines embedded in electrospun fibers for the photoinactivation of Escherichia coli in water

  • Authors: Osifeko, Olawale L , Nyokong, Tebello
  • Date: 2014
  • Language: English
  • Type: Article
  • Identifier: vital:7304 , http://hdl.handle.net/10962/d1020381
  • Description: Lead (II) pyridyloxyphthalocyanine (PbTpyPc) and its quaternized form (PbTepyPc) were synthesized and the photophysical behavior examined. Low fluorescence quantum yields (ΦF) of 0.01 and 0.02 were observed for PbTepyPc and PbTpyPc, respectively. The singlet oxygen quantum yields (ΦΔ) were 0.60 and 0.68, for PbTepyPc and PbTpyPc, respectively using DPBF as a quencher in DMF. Singlet oxygen production of the embedded sensitizers in electrospun fiber were quantified using ADMA and were found to be ΦΔ = 0.41 and ΦΔ = 0.21 for PbTepyPc and PbTpyPc, respectively. Photodynamic inactivation of Escherichia coli (E. coli) with the quaternized photosensitizer at 5 μM, totally inactivated the E. coli (with log CFU = 10 decrease). Only 0.4 log CFU decrease was obtained with PbTpyPc. The embedded non-quaternized photosensitizer (PbTpyPc) was less active on the gram negative bacteria but the quaternized photosensitizer (PbTepyPc) was effective towards inactivation of E. coli. , Original publication is available at http://dx.doi.org/10.1016/j.dyepig.2014.05.010
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Apprehension of bias and the spectacle of the fair-minded observer: a survey of recent commonwealth and South African decisions on pre-judgment

  • Authors: Okpaluba, Chuks , Juma, Laurence
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/126107 , vital:35850 , http://specjuris.ufh.ac.za/apprehension-bias-and-spectacle-fair-minded-observer-survey-recent-commonwealth-and-south-african
  • Description: A perusal of contemporary Commonwealth case law reveals that allegations of bias or apprehension of bias tend to revolve around the pecuniary or other interests of the Judge arising from kinship, previous relationship, or association with party or counsel.1Apparent bias could also be inferred from the judge‘s conduct or utterances, especially, his/her criticisms or cumulative criticisms of a party during proceedings or in adjudication.2In other instances, a judge‘s previous knowledge or association with the case in court, or of an important witness, may disqualify him/her from sitting or passing judgment in the case.3
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