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The involvement of TRAP1 in the mitochondrial localization of STAT3 in mammalian cells

  • Authors: Kadye, Rose
  • Date: 2014
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/55760 , vital:26731
  • Description: STAT3 (signal transducer and activator of transcription 3), an oncogene and transcription factor of genes involved in cellular differentiation, proliferation and immune function, that classically localizes in the cytosol and nucleus has also been found in the mitochondria. However, STAT3 does not have a mitochondrial transit peptide, and its mechanism for mitochondrial localization is unknown. Cytosolic Hsp90s chaperone STAT3 to the nucleus therefore we investigated the involvement of the nuclear-encoded mitochondrial Hsp90 molecular chaperone tumor necrosis receptor associated protein 1 (TRAP1) in STAT3’s mitochondrial localization. Using TRAP1 transient over-expression, STAT3 inhibitor S3I- 201 and Hsp90 inhibitor geldanamycin, we demonstrate that TRAP1 and STAT3 co-localize and co-immunoprecipitates in mammalian systems. Taken together with the observation that STAT3 potentially directly interacts with TRAP1, these data suggest that TRAP1 plays a role in the mitochondrial localization of STAT3.
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The Kansanshi Cu-Au deposit, Domes region, Zambia : geology, mineralisation and alteration characteristics in the main pit

  • Authors: Chinyuku, Donald Tichaona
  • Date: 2014
  • Subjects: Kansanshi Mine -- Zambia , Copper mines and mining -- Zambia , Gold mines and mining -- Zambia , Gold -- Assaying -- Zambia , Geology -- Zambia , Mineralogy -- Zambia , Tillite
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5051 , http://hdl.handle.net/10962/d1011758 , Kansanshi Mine -- Zambia , Copper mines and mining -- Zambia , Gold mines and mining -- Zambia , Gold -- Assaying -- Zambia , Geology -- Zambia , Mineralogy -- Zambia , Tillite
  • Description: The Kansanshi Cu-Au deposit located in the Domes region of the North West province of Zambia is characterised by structurally controlled high angle veins and associated alteration halos. The northwest trending Kansanshi antiform flanks the Solwezi syncline to the north and hosts the Kansanshi deposit and consists of tillites and metasedimentary rocks. Mineralisation is associated with Neoproterozoic Pan African deformation events experienced during the formation of the Lufilian fold belt; however recent findings confirm that structures in the form of reverse and normal faults and drag folds are critical controls on mineralisation within the deposit, Main pit in particular. Low angle faults occurring below the current pit are believed to have served as major fluid pathways during mineralisation. Age dating data from the Kansanshi deposit suggest that mineralisation took place between 512 and 503 Ma indicating that the event was associated with metamorphism. Two types of alteration are dominant within the Main pit (Kansanshi deposit) with the type and intensity of alteration being largely controlled by lithological units. Albite alteration occurs dominantly in phyllites and schists whereas dolomitisation is prevalent in calcareous units. Alteration is associated with mineralisation, and therefore is used as a condition for predicting vein or disseminated mineralisation. The high Au tenor at Kansanshi can be attributed to gold grains occurring in association with melonite (NiTe₂) and microfractured pyrite intergrown with chalcopyrite in sulphide and quartz dominated veins and veinlets. Analysis of gold grade distribution within the Main pit shows a clear concentration of the element along the major north-south trending structures like the 4800 and 5400 zones, possibly through supergene enrichment in the oxide-transition-sulphide zones. It is imperative that exploration for Kansanshi-type deposits will require geochemical and geophysical studies, understanding of the geology of an area to identify the three lithostratigraphic units (red beds, evaporites and reducing strata).
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The large scale bioinformatics analysis of auxiliary activity family 9 enzymes

  • Authors: Moses, Vuyani
  • Date: 2014
  • Subjects: Bioinformatics -- Analysis , Cellulose -- Biodegradation , Biomass energy
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4145 , http://hdl.handle.net/10962/d1016356
  • Description: Biofuels have been proposed to be a suitable replacement to the already depleting fossil fuels. The complex structures of plant biomasses present a challenge the production of biofuels due to recalcitrance. The complex cellulose structure and hydrogen bonding between repeat units of cellulose is believed to be a major contributor to the recalcitrance of cellulose. Fungal organisms come equipped with various oxidative enzymes involved in degradation of plant biomass. The exact mechanism of cellulose degradation remains elusive. The GH61 is a group of proteins which are PMOs. GH61 sequences where previously described as endoglucanases due to weak endoglucanase activity. These enzymes were later found not possess any enzyme activity of their own however they could enhance the activity of other cellulose degrading enzymes. As a result reclassification of these enzymes as AA9 has been implemented. AA9 proteins have been reported to share structural homology with the bacterial AA10 group of enzymes. Based on cleavage products that are produced when AA9 proteins interact with cellulose, AA9 proteins have been grouped into three types. To date the exact mechanism and the sequence and structural basis for differentiating between the various AA9 types remains unknown. Using various bionformatic techniques sequence and structural elements were identified for distinguishing between the AA9 types. A large dataset of sequences was obtained from the Pfam database from UNIPROT entries. Due to high divergence of AA9 sequences, a smaller dataset with the more divergent sequences removed was created. The inclusion of the reference sequences to the data set was done to observe which sequences belong to a certain type. Phylogenetic analysis was able to group AA9 proteins into three distinct groups. MSA and motif analysis revealed that the N-Terminus of these proteins is mostly responsible for type specificity. Structural analysis of AA9 PDB structures and homology models allowed the effect of physicochemical properties to be gauged structurally. The presence of 310 helices and aromatic residues the surface of AA9 sequences is an observation which still warrants further investigation.
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The leadership competencies subordinates value : an exploratory study across gender and national culture

  • Authors: Gondongwe, Sharon
  • Date: 2014
  • Subjects: Leadership , Organizational behavior , Organizational behavior -- Cross-cultural studies , Organizational behavior -- Sex differences
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:1203 , http://hdl.handle.net/10962/d1015673
  • Description: The effectiveness of leadership is largely dependent on whether the leadership competencies exhibited by leaders are congruent with the value system endorsed by subordinates. One of the ways in which leaders can influence subordinates is by understanding the leadership competencies valued by subordinates. Gender and national culture are two of the many factors that have an influence on the leadership competencies valued by subordinates. A large amount of research has been conducted to determine if, indeed, gender and national culture influence the leadership competencies subordinates' value. However, most of this research has been conducted in Europe and North America, places in which national cultures differ significantly from those prevailing in African countries. This study, from a South African and Zimbabwean perspective, attempted to ascertain if gender and national culture influence the leadership competencies they value in their leaders. Existing studies have indicated that gender and national culture do not influence the leadership competencies valued in a leader. The findings of this study are in accordance with previous research and agree that gender and national culture do not influence the leadership competencies valued in a leader. The results of this study indicated that male and female subordinates value similar leadership competencies. With respect to national culture, both South African and Zimbabwean subordinates value similar leadership competencies. Based on the findings of this study, regardless of gender and national culture, all subordinates value a leader who is loyal, visionary, openly embodies integrity, and is a leader who empowers subordinates.
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The life history traits of the arctiine moth Pareuchaetes insulata, a biological control agent of Chromolaena odorata in South Africa

  • Authors: Uyi, Osariyekemwen O , Zachariades, Costas , Hill, Martin P
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/406170 , vital:70244 , xlink:href="https://hdl.handle.net/10520/EJC160238"
  • Description: Pareuchaetes insulata (Walker) (Lepidoptera: Erebidae: Arctiinae) was released in KwaZulu-Natal, South Africa, as a biological control agent against Chromolaena odorata (L.) King and Robinson (Asteraceae) between 2001 and 2009. Although the moth did establish at one out of some 30 release sites, its population level is generally low in the field. Two closely related biological control agents, P. pseudoinsulata Rego Barros and P. aurata aurata (Butler) had previously failed to establish despite several years of releases. Studies of life history traits of P. insulata (males and females) were conducted to determine whether several aspects of its developmental and reproductive biology can explain its poor performance, and to compare the development and reproductive biology of P. insulata with the two other closely related species. At 25 °C, overall mortality of immature stages was generally low (below 12 %). Although the duration of the larval life stage was statistically longer for females, overall they eclosed as adults before the males (i.e. protogyny). Pupal mass, growth rate and total leaf area consumed were higher in females. Mated females laid 74% of their eggs on the first four nights following eclosion and lived an average of 5.92 ± 0.19 days. The moth also showed good biological attributes such as high fecundity (number of eggs), egg hatchability and female mating success (the number of matings that resulted in fertile eggs). Significant positive correlations were detected between insect performance metrics and leaf consumption and between fecundity and pupal mass. A 23 % greater lifetime reproductive output (387.62 ± 19.50 eggs per female) for P. insulata compared with P. aurata aurata was recorded. We hypothesize that the absence of protandry in P. insulata might have contributed to the low population levels of the moth in the field. The results of this study contribute to our understanding of the life history traits of erebid moths in the subfamily Arctiinae deployed for the biological control of C. odorata.
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The lived experiences of HIV-positive women in poverty

  • Authors: Msengana, Sweetlener Thobeka
  • Date: 2014
  • Subjects: HIV-positive women -- South Africa -- Grahamstown , HIV infections -- Psychological aspects -- South Africa -- Grahamstown , HIV infections -- Social aspects -- South Africa -- Grahamstown , Poor -- South Africa -- Grahamstown , Poverty -- Social aspects -- South Africa -- Grahamstown , Poverty -- Psychological aspects -- South Africa -- Grahamstown , Stigma (Social psychology) -- South Africa -- Grahamstown
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3240 , http://hdl.handle.net/10962/d1013269
  • Description: The focus of this study was on the experiences of a small sample of local women who are HIVpositive and are living in poverty. The researcher was interested in exploring the psychological and social experiences of these women using Interpretive Phenomenological Analysis. This research aimed at giving these women a voice to express their first-hand, personal accounts of living with HIV in poverty. Data was analysed for meaningful units, which were interpreted inductively and hermeneutically, and categorised into super-ordinate themes. Six themes within the participants' experiences of living with HIV were determined, namely: (I) experiences of diagnosis, (2) disclosure experiences, (3) stigma, (4) ARV experiences, (5) experiences of social support and (6) poverty. This research found that after an HIV-positive diagnosis, most women experience a variety of emotional reactions. These reactions however seem to change overtime into positive acceptance of the HIV diagnosis. Most of the women in this study preferred to use partial disclosure than to fully disclose their HJV-positive status openly to families, friends and to their community. Reasons for not using full disclosure included fear of discrimination and stigma, which included a fear of being rejected or being blamed for their status and a fear of losing relationships. It was also evident from the findings that most of the women had experienced stigma directly and therefore partial disclosure was used as a coping mechanism to protect the self from further harm. It was also revealed that stigma not only has a negative impact on disclosure but also on social support and ARV experiences. Because ofHIV-related stigma, lack of social support was a struggle that almost all the women in this study had experienced. Lack of understandings about their medication also had a negative impact of the ARV experiences. Stigmas along with poverty are the major struggles that HIV -positive women have to deal with in their day to day living. The findings of this study reveal a need for further research in this experiential area as well as campaigns and education around issues such as stigma, medication, and emotional difficulties associated with HIV.
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The meanings of citizenship: media use and democracy in South Africa

  • Authors: Wasserman, Herman , Garman, Anthea
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/159901 , vital:40354 , https://doi.org/10.1080/02533952.2014.929304
  • Description: In 1994, South Africans embarked on a project to create new meanings of citizenship in order to transcend the disenfranchisement and divisions created by apartheid. This article examines the context in which new forms of citizenship are evolving in South Africa and how South African citizens use the media to give meaning to concepts such as “an active public sphere,” “civic agency” and “participatory politics.” The objective of the research is to provide information about the way in which the media contribute to the quality of democracy in South Africa through mediating citizenship in a way that improves prospects for citizens to exert influence over public decisions.
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The media, Equal Education and school learners : an investigation of the possibility of 'political listening' in the South African education crisis

  • Authors: Mufamadi, Azwihangwisi Eugene
  • Date: 2014
  • Subjects: Equal Education (Nonprofit organisation) Journalism, Educational -- South Africa Educational equalization -- South Africa Journalism -- Political aspects -- South Africa Education -- Citizen participation Educational change -- South Africa Qualitative research
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3524 , http://hdl.handle.net/10962/d1011874
  • Description: This study sets out to investigate democratic participation in South Africa and the role that media play and can potentially play within this context. It considers a social movement, as one way in which citizens can organise themselves and make their voices heard to improve their chances of making a meaningful contribution to democracy. It employs Susan Bickford's theory of 'political listening', which offers a potential solution to the lack of political representativeness and inclusiveness, by focusing on the way citizens relate to each other through speaking, listening and dialogue. This study examines whether the interaction between learners and the social movement Equal Education could be considered 'political listening', and the current and possible role of the media within this context of participation. The study also attempts to develop and make a contribution to the language of description for the theory of political listening in order to map it onto the data. Using evidence or data gathered through observation of Equal Education's youth group meetings with learners and in-depth interviews with learners, youth group facilitators, Equal Education staff members and journalists, this study shows how the interaction amongst learners and between Equal Education and learners could be considered political listening and how the social movement works as a democratic project which offers learners an opportunity to exercise their citizenship. Furthermore, it also details the current role of the media and possible role of the media as perceived by Equal Education, learners and by journalists who report on Equal Education's activities. The study does not make conclusive claims about whether 'political listening' occurs between Equal Education and learners and the media because the study is exploratory in nature and involves a lot of trial and error when it comes to applying the theory of political listening to interview and textual data, which is a communication context that the theory is only beginning to chart.
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The natural history of the humpback dolphin, Sousa chinensis, in KwaZulu-Natal, South Africa : age, growth and reproduction

  • Authors: Nolte, Zianca
  • Date: 2014
  • Subjects: Sousa -- South Africa -- KwaZulu-Natal , Dolphins -- Behavior -- South Africa -- KwaZulu-Natal , Dolphins -- Age determination -- South Africa -- KwaZulu-Natal , Dolphins -- Development -- South Africa -- KwaZulu-Natal , Dolphins -- South Africa -- KwaZulu-Natal -- Reproduction , Dolphins -- Physiology -- South Africa -- KwaZulu-Natal
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5878 , http://hdl.handle.net/10962/d1013178
  • Description: Globally, inshore cetaceans are being threatened by a number of anthropogenic activities. The Indo-Pacific humpback dolphin, Sousa chinensis, is currently listed as ‘near threatened’ by the International Union for the Conservation of Nature (IUCN). In order to be able to advise on management and conservation strategies, knowledge on the life history of the species is required. To date very little is known about the biology of humpback dolphins. The aim of the present study was to determine basic life history parameters, including age, growth and reproduction of humpback dolphins incidentally caught in shark nets. Age was estimated by counting the growth layer groups (GLGs) in the dentine and cementum of sectioned and stained teeth. Both a Von Bertalanffy and a Gompertz growth curve fitted well to the data, but for comparison with previous studies on Sousa, the Gompertz growth function was adopted to describe the relationship between length and age for KwaZulu-Natal populations. Length at birth was estimated between 104.33 and 111.57 cm for males and females, respectively. Asymptotic length was reached at 266.48 cm and 239.29 cm for males and females, respectively. This corresponds to the attainment of physical maturity at 24 GLGs in males and 16 GLGs in females. Asymptotic mass for males could not be determined, while for females it occurred around 160 kg. The maximum age estimates and recorded lengths were 24 GLGs and 279 cm for males and 17.7 GLGs and 249 cm for females. Differences in length-at-age and mass-at-age for S. chinensis suggest sexual dimorphism. The attainment of sexual maturity in males occurred between 9 and 10 GLGs, corresponding to 230 cm total body length and 140 kg. The maximum combined testis mass of mature males comprised 0.42% of total body mass, and a roving male mating system was proposed. In females, sexual maturity occurred around 7.6 GLG, between 220 and 222 cm and 104 - 140 kg. The ovulation rate is estimated at 0.2 ovulations per annum, suggesting a calving interval of five years. It is evident from the results obtained in the present study that geographical differences exist in the life history parameters of S. chinensis. As a result, regional conservation and management strategies are imperative. Results from this study can therefore assist in assessing the status of existing population structures in the KwaZulu-Natal coastal waters, and the implementation of regional mitigation strategies to ensure the continued survival of humpback dolphins in the region.
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The networking of chaperones by co-chaperones: control of cellular protein homeostasis

  • Authors: Edkins, Adrienne L , Blatch, Gregory L
  • Date: 2014
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/165107 , vital:41209 , ISBN 978-3-319-11731-7
  • Description: Co-chaperones are important mediators of the outcome of chaperone assisted protein homeostasis, which is a dynamic balance between the integrated processes of protein folding, degradation and translocation. The Networking of Chaperones by Co-chaperones describes how the function of the major molecular chaperones is regulated by a cohort of diverse non-client proteins, known as co-chaperones. The second edition includes the current status of the field and descriptions of a number of novel co-chaperones that have been recently identified. This new edition has a strong focus on the role of co-chaperones in human disease and as putative drug targets. The book will be a resource for both newcomers and established researchers in the field of cell stress and chaperones, as well as those interested in cross-cutting disciplines such as cellular networks and systems biology.
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The origin of endorheic pans on the African erosion surface North of Grahamstown, South Africa

  • Authors: Alistoun, Judith Robyn
  • Date: 2014
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4775 , http://hdl.handle.net/10962/d1011048
  • Description: Pans on the African Erosion Surface near Grahamstown are small features, which, perhaps due to their small size have been neglected by researchers. From the outset the striking difference of these pans relative to other pans in southern Africa, is that the host rock is silcrete, a highly resistant rock well known as being associated with deeply weathered plateaus. The dominant origin theory for pans in southern Africa was developed by Goudie and Thomas (1985), and focuses on mechanisms relating to erosion and deflation. This model does not fit in well with the pans that have formed on substrate that has largely been unaffected by erosion in recent geological history (thousands to 10 000 years). As such this study examined the role of prolonged chemical weathering of Dwyka Tillite, that has led to the formation of silcrete. The hypothesis was that such deep weathering is responsible for local scale volume changes, which have in turn led to the formation of a depression. The centre of the pan indicated the highest concentration of Al₂O₃ and kaolinite at mid depths, and their concentrations decreased vertically away from these depths, and laterally towards the margins of the pan. Similar results were noted for SiO₂, while CaO and MgO (and calcite and dolomite) were highest at mid depths along the margins of the pan, and decreased laterally toward the centre of the pan. Results indicated that there was a positive relationship in the centre of the pan between: - the degree of chemical weathering and volume losses, - relative elevation of the pan and volume changes. Geochemically and mineralogically, there was a link between the high concentrations of Ca and Mg carbonates and volume gains in the margin of the pans. It is proposed that transpiration of vegetation along the margin of the pan caused the lateral movement of solutes, and the selective exclusion of these solutes by plants was associated with carbonate precipitation, leading to the creation of local relief. These results provide evidence to suggest that weathering and precipitation processes occurring over geological time scales are responsible for minor scale relief features, whose origin has been mistakenly attributed to deflation processes occurring over hundreds to thousands of years.
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The perceived visual impacts and attitudes of the Grahamstown community towards the Waainek Wind-Farm

  • Authors: Cruickshank, Kyle Mark
  • Date: 2014
  • Subjects: Renewable energy sources -- South Africa -- Grahamstown Wind power plants -- South Africa -- Grahamstown -- Public opinion Wind power plants -- Social aspects -- South Africa -- Grahamstown Wind power plants -- Environmental aspects -- South Africa -- Grahamstown Wind power plants -- Economic aspects -- South Africa Wind turbines -- South Africa
  • Language: English
  • Type: Thesis , Masters , MEcon
  • Identifier: vital:1085 , http://hdl.handle.net/10962/d1011768
  • Description: Renewable energy has become an important feature of most modern economies with clean and non-exhaustible sources of power being given a greater significance. Wind energy is one of the favoured renewable, as it is (2013) generally the cheapest and most mature technology available for commercial use. The South African government, as outlined by the Department of Energy's Integrated Resource Plan (IRP), aims to install 5 GW (Gigawatts) of wind energy by 2020. However, South Africa has had little experience in the wind energy industry which is limited to two projects, Klipheuwel (2002) and Darling (2008). Much effort has been dedicated to calculating balance sheet costs, which carries uncertainty due to the high reliance on country specific and site specific variables. An aspect which deserves more attention, and is often ignored, is the public‟s attitudes towards local wind farm developments, which have been known to "make or break" a project during the planning stages. Public backlashes have mostly been concerned with the visual "intrusiveness" of wind farms in the landscape. Detrimental effects on scenery, while seemingly innocuous, are acknowledged as being the single largest barrier to successful wind farm development. Individuals within an area become sentimentally attached to their surroundings, where significant rapid changes in the landscape are viewed as "damage". Economics recognises such declines in scenic resources as market failures, where an externalised cost is passed on to the public and is often not accounted for by private parties responsible for the liability. The primary objective therefore was to measure the magnitude of the visual impact, caused by the Waainek Wind Farm, on the Grahamstown community. Conventional NIMBY¹ (not in my back yard) reasoning, which seeks to explain local wind farm resistance, has attracted criticism with regard to its simplistic approach to wind farm problem identification. Contemporary arguments propose that NIMBY is a poor explanation for the trouble experienced on the local level because it groups problems into one all-encompassing term, leaving much of the discontent unexplained. Instead, the NIMBY explanation is really a broad set of unattended problems, largely resulting from the unsound practices present in the public participation process. Insufficient community involvement and disparities in the negotiation power structures have become the recent focus in wind farm literature. Essentially, these disparities force opposition groups to select factors which may seem more serious to developers, leading to ineffective remedial measures because the core underlying problems are not being remedied. Thus these considerations formed an additional area of investigation. No NIMBY effect was found for the Grahamstown community, as support for both the local and general level was roughly 80%. The public participation process on the other hand revealed that while many found the practices of the developer to be unfair, attitudes towards the wind farm were not adversely affected, especially for the lower income Grahamstown East areas. While the public participation process in this instance did not have any effect on people’s attitudes, careful inspection of the circumstances need to be given. Wind farms are new to South Africa, where the novelty and benefits are the focus of enthusiasm. Job opportunities as well as clean energy are positive drivers for attitudes; however given time, once the anticipation for wind farms dulls, real problems may be revealed. Thus it is crucial to implement good practice procedures during the public participation process, especially when national adoption rates of wind energy are low. Early implementation of an effective public participation process system will ensure that when major problems do arise in future projects, experience and institutional processes would have had ample opportunity to evolve appropriately over a period of time. The double bounded Contingent Valuation Method was used to value the impact of the wind farm on the Waainek scenery through a hypothetical scenario based procedure which presented pictures of the landscape before and after the wind farm had been installed. Based on the perceived impact of the wind farm, respondents were asked their Willingness to Pay to relocate the development, based solely on visual impacts. Learning design Contingent Valuation (Bateman et al., 2008) is a novel technique employed to familiarize respondents with the hypothetical market institution as well as the scenic goods being valued. Average Willingness to Pay was found to be R67 per month, with a final total monthly negative visual impact of R104,000 to R121,000 per month for the entire Grahamstown community. Grahamstown Central (middle-high income) residents were more likely to pay than Grahamstown East (low-middle income) East residents because of socio-economic differences present in each area. A ranking exercise determined that while negative visual impacts are present, the overall benefits derived from the wind farm are potentially much higher. Additionally, positive scenic improvements were found, but were not measured due to time constraints, and would have worked to reduce the net visual impact of the Waainek Wind Farm. ¹Problem where individuals support the general concept of wind power, but when it comes to local implementation, opposition to the development arises within the same group.
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The personality of an entrepreneur : a psychobiography of Steve Jobs

  • Authors: Ndoro, Tinashe T R
  • Date: 2014
  • Subjects: Jobs, Steve, 1955-2011 -- Psychology , Personality assessment , Psychology -- Biographical methods , Businesspeople -- Psychology , Psychohistory , Entrepreneurship -- United States , Businesspeople -- United States
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:833 , http://hdl.handle.net/10962/d1013215
  • Description: From Integrative Summary: There has been a growing interest in successful entrepreneurs. Research on entrepreneurship has focused on the identification of personality variables that would assist in the prediction of entrepreneurial success. The present study moves away from attempting to predict entrepreneurial success and instead focuses on exploring and describing the personality of a successful entrepreneur. A psychobiographical case study was adopted by the researcher to explore and describe the extent to which Steve Jobs demonstrated the entrepreneurial characteristics identified by Rauch and Frese (2007). A personality trait approach to entrepreneurship was adopted in the study. The study also attempted to explore the socio-cultural and economic context within which Jobs practised his entrepreneurial activities. Jobs was a successful entrepreneur who co-founded Apple and founded NeXT and Pixar, which were all companies that transformed various technological industries. His entrepreneurial orientation allowed him to produce innovative products that transformed society in various sectors which included personal computing, mobile phones, music, retail stores and films (Isaacson, 2011). A qualitative approach was adopted in the study. The data collection and analysis was guided by the three linked sub-processes proposed by Miles and Huberman (2002) which involved data reduction, data display and conclusion drawing and verification. The findings of this study showed that Jobs demonstrated, at varying levels, all the entrepreneurial characteristics identified by Rauch and Frese (2007) which included a need of achievement, risk-taking, innovativeness, autonomy, locus of control and self-efficacy. The researcher however noted that the desire for autonomy, risk-taking, innovativeness and self-efficacy were the most dominant characteristics driving his entrepreneurial orientation. The research thesis adopted the structure of a teaching case which can be used to explore and discuss the personality trait perspective to entrepreneurship in a classroom setting. The findings of the study can be recognised as positively contributing to the growing field of psychobiographical research on exceptional individuals, including entrepreneurs. The study can be considered as a foundation for future studies which will add to the body of knowledge relating to entrepreneurship and personality.
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The plasmodium falciparum exported Hsp40 co-chaperone, PFA0660w

  • Authors: Daniyan, Michael Oluwatoyin
  • Date: 2014
  • Subjects: Molecular chaperones Heat shock proteins Proteins -- Analysis Proteins -- Structure Plasmodium Plasmodium falciparum Malaria -- Prevention -- Research
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4108 , http://hdl.handle.net/10962/d1011780
  • Description: Plasmodium falciparum is the pathogen that is responsible for the most virulent, severe and dangerous form of human malaria infection, accounting for nearly a million deaths every year. To survive and develop in the unusual environment of the red blood cells, the parasite causes structural remodelling of the host cell and biochemical changes through the export of virulence factors. Among the exportome are the molecular chaperones of the heat shock protein family, of which Hsp40s and Hsp70s are prominent. PF A0660w, a type II P. falciparum Hsp40, has been shown to be exported in complex with PfHsp70-x into the infected erythrocyte, suggesting possible functional interactions. However, the chaperone properties of PF A0660w and its interactions with proteins of parasite and human origin are yet to be investigated. Using a codon optimised coding region, PF A0660w was successfully expressed in E. coli M 15 [pREP4] cells. However, the expressed protein was largely deposited as insoluble pellet, and analysis of the pellets revealed a high percentage of PF A0660w, characteristic of inclusion body formation. PF A0660w was purified from inclusion bodies using additive enhanced solubilisation and refolding buffers followed by nickel affinity chromatography. SDS-PAGE and western analysis revealed that the purified protein was of high purity. Size exclusion chromatography showed that the protein existed as a monomer in solution and the secondary structure analysis using Fourier transformed infrared spectroscopy (FTIR) confirmed the success of the refolding approach. Its monomeric state suggests that PF A0660w may be functionally different from other Hsp40 that form dimers and that for PF A0660w, dimer formation may not be needed to maintain the stability of the protein in solution, but may occur in response to functional necessities during its interaction with partner Hsp70. PFA0660w was able to significantly stimulate the ATPase activity ofPfl-Isp70-x but not Pfl-Isp70-1 or human Hsp70 (HsHsp70), suggesting a specific functional interaction. Also, PF A0660w produced a dose dependent suppression of rhodanese aggregation and cooperated with Pfl-Isp70-1, PfHsp70-x and HsHsp70 to cause enhanced aggregation suppression. Its ability to independently suppress aggregation may help to maintain substrates in an unfolded conformation for eventual transfer to partner Hsp70s during refolding processes. Also, the in vivo characterisation using a PF A0660w peptide specific antibody confirmed that PF A0660w was exported into the cytosol of infected erythrocytes. Its lack of induction upon heat shock suggests that PF A0660w may not be involved in the response of the parasite to heat stress. Overall, this study has provided the first heterologous over-expression, purification and biochemical evidence for the possible functional role of PF A0660w, and has thereby provided the needed background for further exploration of this protein as a potential target for drug discovery.
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The post-secondary education system: Towards policy formulation for equality and development

  • Authors: Badat, Saleem
  • Date: 2014
  • Language: English
  • Type: Text
  • Identifier: vital:7861 , http://hdl.handle.net/10962/d1016410
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The potential and reality of the Living Lab model of ICT for Development (ICT4D) in the rural development context : the case of Siyakhula Living Lab, Dwesa, Eastern Cape, South Africa

  • Authors: Mosuoe, Teboho Priscilla
  • Date: 2014
  • Subjects: Siyakhula Living Lab , Information technology -- South Africa -- Dwesa-Cwebe , Communication in economic development -- South Africa -- Dwesa-Cwebe , Rural development projects -- South Africa -- Dwesa-Cwebe , Rural development -- Economic aspects -- South Africa -- Dwesa-Cwebe , Rural development -- South Africa -- Dwesa-Cwebe -- Sociological aspects , Rural development projects -- Evaluation , Social networks -- South Africa -- Dwesa-Cwebe
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:3381 , http://hdl.handle.net/10962/d1013289
  • Description: This thesis explores the contribution of Information and Communication Technology (ICT) in rural development processes. Within the framework of social capital theory, and in the context of the information society, the study examines how the collaborative and innovative model of ICT for Development (ICT4D) can enhance social networks and information channels in rural communities, thereby enabling the active participation of rural community members in their own development processes. The study examines networks and information channels both within the rural communities under investigation and between these communities and other sectors in the society. The thesis studies the case of the Siyakhula Living Lab (SLL), an ICT4D initiative in the Mbashe Municipality of the Eastern Cape Province of South Africa. During the investigation, four types of networks were identified: local organisations, social institutions, collective community projects and social ties. It was found that the Living Lab has so far influenced the creation of new forms of networks through the common spaces (computer labs) which have been made available by the Living Lab. The study further showed that the use of computers has enabled other community members to partake in the wider community of online/virtual social networks, allowing them to communicate and share information with those outside their own communities. The study also showed that the Living Lab has enabled the networking of these communities with other sectors such as academia. It was, however, found that so far the existence of the Living Lab has not influenced the already existing local networks in these communities. Also, the study showed that the relationship between these rural communities and their government and industry partners as stakeholders in the Living Lab is currently ineffective. Nevertheless, this situation has a potential to change in the future as there are ICT applications which have been developed through collaboration with rural community members, which will assist in enhancing communication between these rural communities and other stakeholders. The study finally revealed that social networks do contribute to the functioning of communities by providing both monetary and social support to community members, even though, in effect, the monetary benefits are somewhat limited by a number of factors. It is revealed that the engagement of ICT could go a long way in improving social and economic activities, governance and service delivery, as well as education in these communities.
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The preparation of antigen for the generation of polyclonal antibodies against the capsid subunit, VP1, and the viral protease, 3Cpro, of Theiler's murine encephalomyelitis virus (TMEV)

  • Authors: Moetlhoa, Boitumelo
  • Date: 2014
  • Subjects: Enteroviruses , Encephalomyelitis , Antigens
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4118 , http://hdl.handle.net/10962/d1013225
  • Description: The Picornaviridae is a family of viruses of economic importance that have a major impact on human and animal health. Some of the major genera found in the Picornaviridae family are Enterovirus which includes Poliovirus (PV) and Human Rhinovirus (HRV), Cardiovirus which includes Theiler’s murine encephalomyelitis virus (TMEV) and Saffold virus (SAFV), Aphthovirus of which the Foot and Mouth disease virus (FMDV) is a member and Hepatovirus which includes Hepatitis A virus (HAV). Picornaviruses have a single stranded, positive sense RNA genome which is approximately 7.5-8.4 kb pairs in size. The picornavirus genome is translated into a large polyprotein and is proteolytically cleaved by viral proteases namely 2Apro, 3Cpro and 3CDpro into mature viral structural and non-structural polypeptides encoded by the P1, P2 and P3 domains. Picornaviruses utilise host cell machinery and cellular pathways for entry and uncoating, genome replication and capsid assembly. In our laboratory, we are studying the mechanisms by which TMEV interacts with host cell components and our recent research shows that molecular chaperones are required for a production infection. To follow up on this observation, the overall aim of this study was to prepare antigen for the generation of polyclonal antibodies against the TMEV VP1 and 3Cpro proteins. To this end, the TMEV VP1 and 3Cpro amino acid sequences were analysed to identify hydrophobic, hydrophilic and antigenic regions. Homology modelling was performed in order to predict linear B cell epitopes exposed on the surface of the protein structures. The full length coding sequences of VP1 and 3Cpro were selected for amplification by the PCR and cloning into pQE-80L for expression in a bacterial system. Time course induction studies of recombinant VP1 and 3Cpro showed that the proteins were maximally expressed at 6 hrs and 4 hrs respectively. Recombinant VP1 was solubilised using the detergent, Sarcosyl and purified by Nickel affinity chromatography under native conditions. Because recombinant VP1 co-purified with an unidentified protein, the pET expression system was used. Although no protein of the estimated size was observed by SDS-PAGE analysis in the time course induction study, Western analysis using anti-His6 (2) antibodies detected a signal of ~35 kDa. Solubility studies resulted in the presence of two protein bands in the insoluble fraction resolved between 35 and 40 kDa. Recombinant 3Cpro expressed in a bacterial system was predominantly present in the insoluble fraction. Treatment with Sarcosyl had no effect on the solubility of the recombinant protein and it was therefore purified under denaturing conditions using 8M urea. Following dialysis, 3Cpro was used for immunisation of rabbits. Crude anti-TMEV 3Cpro antibodies were able to detect as little as 107 ng of bacterially expressed antigen at a dilution of 1:100 000 by Western analysis. The presence of contaminating proteins was reduced using pre-cleared anti-TMEV 3Cpro antibodies. The antibodies were unable to detect virally expressed 3Cpro in BHK-21 cell lysate supernatant. In an attempt to determine whether TMEV 3Cpro is present in the insoluble fraction, anti-TMEV 3Cpro antibodies were tested using total protein prepared from infected and mock-infected cell lysates. Once again, no protein band the size of 3Cpro was detected. The antibodies were further tested for detection of 3Cpro in TMEV-infected cells by indirect immunofluorescence and confocal microscopy. A diffuse cytoplasmic and perinuclear distribution, as well as nuclear staining, was observed in infected BHK-21 cells. This staining pattern resembled that observed for the HRV, FMDV and EMCV 3Cpro in similar experiments. Further experiments are required to confirm specificity of these antibodies for virally-expressed 3Cpro by Western analysis and indirect immunofluorescence.
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The presumption of gult created by Section 235(2) of the Tax Administration Act: a constitutional and comparative perspective

  • Authors: Faifi, Farai
  • Date: 2014
  • Subjects: Guilt (Law) -- South Africa , Presumption of innocence -- South Africa , Income tax -- Law and legislation -- South Africa , Human rights -- Taxation -- South Africa , Taxpayer compliance -- Moral and ethical aspects -- South Africa , Taxation -- South Africa
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:907 , http://hdl.handle.net/10962/d1012979
  • Description: This research examined the legal nature of the presumption of guilt created by section 235(2) of the South African Tax Admiration Act and considered whether or not its practical application violates the taxpayer’s fundamental right contained in section 35(3) of the Constitution, which gives every accused taxpayer the right to a fair trial, including the right to be presumed innocent. The research also provided clarity on the constitutionality of this presumption because it has been widely criticised for unjustifiably violating the taxpayer's constitutional right to a fair trial. The conclusion reached is that the presumption created by section 235(2) of the Tax Administration Act constitutes an evidentiary burden rather than a reverse onus. It does not create the possibility of conviction, unlike a reverse onus where conviction is possible, despite the existence of a reasonable doubt. Therefore, it does not violate the accused taxpayer’s the right to a fair trial and the right to be presumed innocent and hence it is constitutional. Accordingly, the chances that the accused taxpayer will succeed in challenging the constitutionality of section 235(2) of the Act are slim.
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The principle of complementarity : a critical analysis of Article 17 of the Rome Statute from an African perspective

  • Authors: Mohami, Thapelo Adelice
  • Date: 2014
  • Subjects: Complementarity (International law) , Rome Statute of the International Criminal Court (1998 July 17) , International Criminal Court , Criminal jurisdiction -- Africa , International crimes -- Africa , Crimes against humanity -- Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:3720 , http://hdl.handle.net/10962/d1013326
  • Description: This thesis attempts to address perennial concerns, mostly raised in some quarters in Africa, pertaining to the development of the complementarity regime established by the Rome Statute of the International Criminal Court. It grapples with a very important question, whether the principle of complementarity, embodied in article 17 of the Rome Statute, was formulated and is being applied by the ICC in a manner that upholds the ideals and theories upon which the regime was founded. The principle of complementarity is designed to mediate the imperatives of State sovereignty and a legitimate international criminal justice system. Essentially, complementarity gives States latitude to try genocide, crimes against humanity, war crimes and aggression nationally, with the ICC only intervening where States are either unable or unwilling to prosecute genuinely. Africa constitutes the biggest regional block of membership to the Rome Statute, however, over the years; support for the ICC on the African continent has waned. It has been argued in some quarters that the ICC is anti-African and that it has interpreted and applied complementarity in a manner that diminishes State sovereignty. The thesis argues that this tension may also be due to textual deficiencies inherent within the Rome Statute, in the provisions that embody this principle. It therefore examines complementarity from a theoretical perspective to provide a comprehensive account of the system contemplated by the drafters of the Rome Statute. In this regard, the thesis argues for expansion of States’ ability at the national level to deal with international crimes without compromising international criminal justice processes or threatening State sovereignty. This is suggested as a way of relieving the tension that has characterised the relationship between African States and the ICC. The thesis further sketches out some of the complexities inherent in the modalities through which the Court may exercise its complementary jurisdiction, particularly within the African continent, given that legal systems in most African countries are particularly weak. It thus dissects the provisions that outline the principle of complementarity in tandem with the Court’s interpretation and application of complementarity in practice. Furthermore, through an exploratory survey of the referral of the Situation in Uganda, and the ICC Prosecutor’s proprio motu investigation of the Situation in Kenya, the thesis illustrates how a positive approach to complementarity can help establish a healthy cooperative synergy between the ICC and States, thereby promoting a functional expeditious criminal justice system. This will go a long way towards assuaging State’s fears that the ICC merely pays lip service to complementarity and arbitrarily supersedes national jurisdiction.
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the programmable bride

  • Authors: Krueger, Anton
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/229698 , vital:49701 , xlink:href="https://hdl.handle.net/10520/EJC156969"
  • Description: the man gently opens his machine and finding an agreeable port for his firm flash, he eagerly installs the software he's been waiting on for so very long... once booted up, the man takes his first tentative steps, finding his bride perfect in every way, already completely in love with him, and dreamy... the man tenderly reaches out for her-she understands him so well, she's concerned about his needs, she wants to know how he feels, wants only to please him, she only-/but-there's an interruption/somebody's on the stairs, someone's knocking at his door-the man is forced to close her down a little too abruptly, shutting the machine to attend to other matters while he's away he can't wait to get back, he thinks about her all the time; he longs to flip his laptop lid up, to open her again... but when finally he silently prises open the instrument of his heart's desires, she seems a little disorientated... he didn't shut her down properly …
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