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Volatility transmission across South African financial markets: does the bull – bear distinction matter?

- Jaramba, Toddy

Authors: Jaramba, Toddy
Date: 2011
Subjects: Finance -- South Africa , Financial institutions -- South Africa , Monetary policy -- South Africa , Portfolio management -- South Africa , Stock exchanges -- South Africa , Foreign exchange -- Mathematical models , Bond market -- South Africa
Language: English
Type: Thesis , Masters , MCom
Identifier: vital:1106 , http://hdl.handle.net/10962/d1013396
Description: The volatility transmission in financial markets has important implications for investment decision making, portfolio diversification and overall macroeconomic stability. This paper analyses volatility transmission across four South African financial markets that is the stock, bond, money and foreign exchange markets, using daily data for the period 2000-2010. It also shows whether the volatilities in the SA financial markets present a different behaviour in bull and bear market phases. The effects of the international markets volatility to the local markets volatility was also looked at in this study. To obtain estimates of market volatility, the study experimented with various volatility models that include the GARCH, EGARCH and TARCH. To examine volatility interaction and the transmission of volatility shocks, a VAR model was estimated together with block exogeneity, impulse response and variance decomposition. The study found that there is limited volatility transmission across the SA financial markets. The study also found that the money market is the most exogenous of all markets since the other three financial markets volatility is insignificant to the money market (see impulse response results). For the bond market, volatility transmission was characterized with a decreasing trend. With regard to international markets volatility, it concluded that, the shocks in the international markets will eventually affect the movement in the local markets. The results also highlighted that, world and local markets are important in accelerating the volatility transmission in SA financial markets depending on whether they are in their bull or bear phases. In the case of South Africa, the study found that volatility transmission across markets is higher during bear market periods than bull market periods. Basing on the study results which show that the volatility transmission is limited across SA financial markets, the implication to local and international investors is that there is a greater potential for diversifying risk by investing in different South African financial markets.
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Date Issued: 2011

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The photophysical properties of low symmetry phthalocyanines in conjunction with quantum dots

- D'Souza, Sarah

Authors: D'Souza, Sarah
Date: 2011
Subjects: Phthalocyanines , Photochemistry , Zinc , Quantum dots , Spectrum analysis , Nanoparticles
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4331 , http://hdl.handle.net/10962/d1004992 , Phthalocyanines , Photochemistry , Zinc , Quantum dots , Spectrum analysis , Nanoparticles
Description: he synthesis, extensive spectroscopic characterization and photophysical studies of low symmetry zinc phthalocyanine have been conducted. Comparisons have been made taking into consideration the influence of the solvent properties as well as substituent type and position. Photosensitizing properties of the zinc phthalocyanine derivatives in the presence of thiol capped CdTe quantum dots (QDs) were compared. The QDs were used as energy transfer donors and to facilitate with energy transfer through Förster resonance energy transfer (FRET) from the QDs to the MPcs. The linkage of unsymmetrically substituted 4-monoaminophenoxy zinc phthalocyanine (ZnAPPc) to CdTe quantum dots capped with mercaptopropionic acid (MPA), L-cysteine (L-cys) or thioglycolic acid (TGA) has been achieved using the coupling agents ethyl-N3 dimethylaminopropyl)carbodiimide (EDC) and N-hydroxy succinimide (NHS), which facilitate formation of an amide bond to form the QD-ZnAPPc-linked complex. The formation of the amide bond was confirmed using UV-Vis, Raman and IR spectroscopies, as well as AFM (atomic force microscopy). Förster resonance energy transfer (FRET) resulted in stimulated emission of ZnAPPc in both the linked (QDZnAPPc-linked) and mixed (QD:ZnAPPc-mixed) conjugates for MPA only. The linked L-cys and TGA complexes (QD-ZnAPPc-linked) gave the largest FRET efficiencies hence showing the advantages of covalent linking. Fluorescence quantum yields of QDs were decreased in QD:ZnAPPc-mixed and QD:ZnAPPc-linked. High triplet state quantum yields were obtained for the linked QD-phthalocyanine derivatives (ZnAPPc)and monoaminozinc phthalocyanine (ZnAPc) compared to when ZnAPPc and ZnAPc were mixed with MPA QDs without a chemical bond.
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Date Issued: 2011

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In vitro toxicity testing of zinc tetrasulfophthalocyanines in fibroblast and keratinocyte cells for the treatment of melanoma cancer by photodynamic therapy

- Maduray, Kaminee, Karsten, Alta, Odhay, Bharti, Nyokong, Tebello

Authors: Maduray, Kaminee , Karsten, Alta , Odhay, Bharti , Nyokong, Tebello
Date: 2011
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/247588 , vital:51597 , xlink:href="https://doi.org/10.1016/j.jphotobiol.2011.01.020"
Description: A series of water-soluble tetrasulfonated metallophthalocyanines (MPcs) dyes have been studied to be used as a drug or photosensitizer (PS) in photodynamic therapy (PDT) for the treatment of cancers. During PDT the PS is administrated intravenously or topically to the patient before laser light at an appropriate wavelength is applied to the cancerous area to activate the PS. The activated PS will react with oxygen typically present in the cancerous tissue to generate reactive oxygen species for the destruction of the cancerous tissue. This in vitro study aimed at investigating the cytotoxic effects of different concentrations of zinc tetrasulfophthalocyanines (ZnTSPc) activated with a diode laser (λ = 672 nm) on melanoma, keratinocyte and fibroblast cells. To perform this study 3 × 104 cells/ml were seeded in 24-well plates and allowed to attach overnight, after which cells were treated with different concentrations of ZnTSPc. After 2 h, cells were irradiated with a constant light dose of 4.5 J/cm2. Post-irradiated cells were incubated for 24 h before cell viability was measured using the CellTiter-Blue Viability Assay. Data indicated high concentrations of ZnTSPc (60–100 μg/ml) in its inactive state are cytotoxic to the melanoma cancer cells. Also, results showed that photoactivated ZnTSPc (50 μg/ml) was able to reduce the cell viability of melanoma, fibroblast and keratinocyte cells to 61%, 81% and 83% respectively. At this photosensitizing concentration the efficacy the treatment light dose of 4.5 J/cm2 against other light doses of 2.5 J/cm2, 7.5 J/cm2 and 10 J/cm2 on the different cell lines were analyzed. ZnTSPc at a concentration of 50 μg/ml activated with a light dose of 4.5 J/cm2 was the most efficient for the killing of melanoma cancer cells with reduced killing effects on healthy normal skin cells in comparison to the other treatment light doses. Melanoma cancer cells after PDT with a photosensitizing concentration of 50 μg/ml and a treatment light dose of 4.5 J/cm2 showed certain apoptosis characteristics such as chromatin condensation and fragmentation of the nucleus. This concludes that low concentrations of ZnTSPc activated with the appropriate light dose can be used to induce cell death in melanoma cells with the occurrence of minimal damage to surrounding healthy tissue.
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Date Issued: 2011

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Towards a critical understanding of media assistance for "new media" development

- Mathurine, Jude

Authors: Mathurine, Jude
Date: 2011
Subjects: Mass media -- Technological innovations , Mass media -- Political aspects
Language: English
Type: Thesis , Masters , MA
Identifier: vital:3459 , http://hdl.handle.net/10962/d1002914 , Mass media -- Technological innovations , Mass media -- Political aspects
Description: The field of media assistance has grown ever more complex with the inclusion of ‘new media’ networks, channels, tools and practices (such as the Internet, satellite television, mobile devices, social media and citizen journalism) to the media development mix. Adding to the ferment is the increasing convergence between the formerly discrete terrains of ICT for development, media for development and (mass) media development. Much of the discussion regarding the utility and objectives of media development in general and ‘new media’ in particular has been viewed through a modernist and techno-determinist prism which offers a limited ideological view of media development and its objects and consequently, a limited set of communication approaches and strategies. This study contextualises the assumptions of media development historically and critically, with particular focus on new media’s roles and relationships with the media environment, and its objectives democratisation and development. Through the application of literature, theory and various research studies, this thesis establishes a broader view of new media’s role and diverse consequences for media development, democracy and development. The study recommends greater collaboration, contextual research and theorisation of media development and new media as part of mixed media systems and cognisant of the multi-dimensional natures of its objects of democracy and development. One implication is the need for professionalisation of the media development and media assistance sector. In relation to the influences of new media on media use and the media as an institution, it motivates the need to address digital divides and emphasise the sustainability of the practice of journalism.
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Date Issued: 2011

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Improving the organisational perfomance of school by increasing the effectiveness of school management teams

- Balie, Isaac Ronald

Authors: Balie, Isaac Ronald
Date: 2011
Subjects: School management teams -- South Africa -- Eastern Cape , School management and organization -- South Africa -- Eastern Cape , School boards -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , MBA
Identifier: vital:8584 , http://hdl.handle.net/10948/1612 , School management teams -- South Africa -- Eastern Cape , School management and organization -- South Africa -- Eastern Cape , School boards -- South Africa -- Eastern Cape
Description: The principal together with the school management team (SMT) of a public school is responsible for ensuring that all areas in the school function effectively. Effective school-based management is no longer a choice in South Africa but, rather, a must. Seventeen years into democracy, the Grade 12 pass rates in the Eastern Cape for the past three years were 50.6% in 2008, 51.0% in 2009 and 58.3% in 2010. Although there has been an improvement over the last three years, the Eastern Cape was still number seven out of the nine provinces in 2010. Against this background the question arose as to whether the schools in the Eastern Cape were effectively managed. The primary objective of the study is therefore to improve the organisational performance of public schools in the Uitenhage education district by investigating the relationship between the perceived effective implementation of basic managerial tasks (planning, organising, leading and controlling), on the one hand, and organisational performance of schools, on the other hand. Convenience sampling was used to select 100 out of a possible 139 senior management team members from 26 public schools in the Uitenhage education district. The sample was stratified to include principals, deputy principals and heads of departments. The empirical results revealed that the management tasks, leading and controlling, were the main determinants of the organisational performance of participating schools. The empirical results showed that planning and organising do not have a significant influence on the organisational performance of these schools. The managerial implications of the results are discussed and recommendations are made on the basis of these discussions.
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Date Issued: 2011

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From physics to music: an analysis of the role of overtones in the improvement of choral tone

- Starker, Leonard Bonn

Authors: Starker, Leonard Bonn
Date: 2011
Subjects: Choral singing , Choral singing -- Intonation , Choral singing -- Instruction and study , Voice culture
Language: English
Type: Thesis , Masters , MMus
Identifier: vital:8518 , http://hdl.handle.net/10948/d1012937
Description: Numerous studies exist examining the link in solo singers between timbre and overtone spectra. The purpose of this study is to examine if similar results can be obtained by applying the same techniques to choral singing. The study is aimed at non-scientific readers and therefore introduces the subject with background to the relevant physics. In this study a number of recorded samples of choirs were taken from www.youtube.com and analyzed. The analysis included computation of long-term average spectra (LTAS) and singing power ratio‟s (SPR), which provided an indication of the relative energy in the higher overtone region of every choir. This was compared to a binary value judgment of the choirs. The results indicate that the SPR as applied to soloists cannot be directly applied to choirs. A link between SPR and a perceived “good” choral tone could exist but would have to be interpreted differently than in the case of soloists. It was also found that a possible link could exist between frequency peaks in LTAS and a choir‟s intonation.
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Date Issued: 2011

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Investigating the socio economic impact of electrification in Mnquma Municipality

- Jobela, Sonwabo

Authors: Jobela, Sonwabo
Date: 2011
Subjects: Electrification -- Social aspects -- South Africa -- Eastern Cape , Electrification -- Economic aspects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , MA
Identifier: vital:9090 , http://hdl.handle.net/10948/d1011507 , Electrification -- Social aspects -- South Africa -- Eastern Cape , Electrification -- Economic aspects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
Description: The aim of this research was to investigate the socio economic impact of electrification in Mnquma Municipality in the province of Eastern Cape. Mnquma Municipality has a backlog of about 25475 households that have not yet been electrified. There is a high demand of electricity in villages that have not yet been electrified. Eskom Southern Region has about 5 Million electrified households. The year 2012 was declared as year of universal access of electricity in South Africa. In the last three years amount of electrified households has been coming down at alarming rate. It is against this background that the study sought to investigate the socio economic impact of electrification of households. This study is a comparative study where two villages are compared. One village is electrified whilst the other village is not electrified. The study is based on the questionnaire opinion survey where respondents‟ views and opinion are solicited to test if electricity improves the socio economic conditions of Mnquma households. The study confirmed the findings of the research if electrification has improved the socio economic condition and if electricity is a preferred source of energy. The study proposed recommendations encompasses strategic responses to check if Government is achieving the desired goal through electrification of households.
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Date Issued: 2011

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Gender oppression and possibilities of empowerment: images of women in African literature with specific reference to Mariama Ba's So long a letter, Buchi Emecheta's The Joys of motherhood and Tsitsi Dangarembga's Nervous conditions

- Nyanhongo, Mazvita Mollin

Authors: Nyanhongo, Mazvita Mollin
Date: 2011
Subjects: Women and literature -- Africa Women and literature -- Africa Women and literature -- Africa Women and literature -- Africa Women and literature -- Africa African literature -- Women authors Women -- Africa -- Literary collections
Language: English
Type: Thesis , Masters , MA
Identifier: http://hdl.handle.net/10353/6411 , vital:29659
Description: This study consists of a comparative analysis of three novels by three prominent African women writers which cast light on the ways in which women are oppressed by traditional and cultural norms in three different African countries. These three primary texts also explore the ways in which African women‟s lives are affected by other issues, such as colonialism and economic factors, and this study discusses this. An analysis of these novels reveals that the interconnectedness of racial, class and gender issues exacerbates the oppression of many African women, thereby lessening the opportunities for them to attain self-realization. This study goes on to investigate whether there are possibilities of empowerment for the women in the primary texts, and examining the reasons why some women fail to transcend their situations of oppression. The primary novels will be discussed in different chapters, which explore the problems with which various women are beset, and discuss the extent to which the various women in the novels manage to attain empowerment. In conclusion, this study compares and contrasts the ways in which the women in the primary texts are oppressed and highlights the reasons why some women are able to attain empowerment, whilst others are unable to do so. It also shows that many women are beset with comparable forms of oppression, but they may choose to react to these situations differently. Over and above these issues, the study seeks to draw attention to the fact that women need to come together and contribute to the ways in which they can attain various forms ofempowerment.
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Date Issued: 2011

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Action competence and waste management: a case study of learner agency in two Grahamstown eco-schools

- Chiphwanya, Nellie Chimwemwe

Authors: Chiphwanya, Nellie Chimwemwe
Date: 2011
Subjects: Environmental education -- South Africa -- Grahamstown -- Case studies Environmental education -- Study and teaching (Primary) -- South Africa -- Grahamstown -- Case studies Student-centered learning -- South Africa -- Grahamstown -- Case studies Refuse and refuse disposal -- Environmental aspects -- South Africa -- Grahamstown -- Case studies Recycling (Waste, etc) -- South Africa -- Grahamstown -- Case studies Active learning -- South Africa -- Grahamstown -- Case studies Competency based education -- South Africa -- Grahamstown -- Case studies
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1956 , http://hdl.handle.net/10962/d1008308
Description: There has been a growing need in environmental education to develop students' ability and will to take part in democratic processes that enable them take environmental action in their local environment. This study examined learner action competence in waste management practices in two primary school contexts in the Eastern Cape, South Africa. An interpretive case study design is used to probe how learner participation in Eco-School waste management practices enabled the acquisition of knowledge in purposeful learning and action experiences that developed the vision and agency of informed action. The research was centred on two guiding questions: 1. How informed, purposeful and action-orientated is learner participation in Eco-School waste management activities? 2. What Eco-School waste management activities are fostering active participation towards a learner-led agency? Educators in the two schools were interviewed and Eco-School portfolios were examined for evidence of the learning activities and learner achievement. This provided the contextual data for reviewing focus group interviews to probe what was significant to learners, what they came to know and how they had contributed to the process of developing better waste management in the Eco-School context. The evidence generated in the study was used to identify the roles of the various players, the significant activities and processes that enabled and constrained the emergence of learner-led agency. The main findings in the study were that teacher intentionality and school management ethos were significant in engaging learners in meaningful waste management activities in both cases. The study also revealed that although most of the waste management activities in both cases were teacher-initiated, there were spaces open for learner initiatives. However, it appeared that the activity based waste management practices mostly allowed learners to learn how to do waste management more than allowing them to find out more about the scope and nature of ii the problem of waste. This then resulted in learners talking more about what they were doing with waste than talking about what they knew about waste. There were differences in the way in which learners approached waste in the two cases. In the one case, Kingswood Junior School learners used waste artistically and carried out activities that allowed for better use of waste resources like paper while in the other School, Grahamstown SDA School, learners approached waste as a resource for making money. However, in both cases, learners appeared to enjoy the positive experiences of doing things that contributed to a cleaner environment and were of benefit to others and this gave them a sense of pride to share their experiences with others. This study was significant as it allowed me to probe learner participation and examine the development of their action competence through listening to the voices of the learners themselves and understanding what was important to them about the knowledge they gained and their vision of better waste management.
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Date Issued: 2011

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Evaluate the effectiveness of the bus rapid transit system within the context of the local economic development in reference to the Nelson Mandela Bay municipality

- Fudu, Nonkanyiso

Authors: Fudu, Nonkanyiso
Date: 2011
Subjects: Port Elizabeth (South Africa) -- Economic conditions , Transportation , Transportation -- Technological innovations
Language: English
Type: Thesis , Masters , MA
Identifier: vital:9087 , http://hdl.handle.net/10948/d1010422 , Port Elizabeth (South Africa) -- Economic conditions , Transportation , Transportation -- Technological innovations
Description: The Nelson Mandela Bay Municipality implemented a new regulated public transport system with the objective to support the Economic and Social development of the City. The system will be done by transforming current diversified minibus taxi and bus operations into integrated city wide system which will provide the citizens with efficient, affordable, accessible and safe public transport services. The decision was based on the 2006 Public Transport Plan (PTP) prepared by Nelson Mandela Bay Municipality. The long term strategy is based on the Nelson Mandela Bay 2020 Vision taking into account national and provincial transport policies. (Public Transport Operational Plan Draft 2008). The plan has been developed by the municipality in collaboration with the Eastern Cape Department of Roads and transport supported by the National Department of Transport.
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Date Issued: 2011

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Stories from forest, river and mountain : exploring children's cultural environmental narratives and their role in the transmission of cultural connection to and protection of biodiversity

- Alexander, Jamie Kim

Authors: Alexander, Jamie Kim
Date: 2011
Subjects: Children and the environment -- South Africa -- Eastern Cape , Conservation of natural resources -- South Africa -- Eastern Cape -- Citizen participation , Environmental education -- South Africa -- Eastern Cape , Human ecology -- South Africa -- Eastern Cape , Oral tradition -- South Africa -- Eastern Cape , Social learning -- South Africa -- Eastern Cape , Traditional ecological knowledge -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , MA
Identifier: vital:6061 , http://hdl.handle.net/10962/d1015267
Description: Preservationist conservation created a legacy of national parks and protected areas that were surrounded by local people dispossessed of their land and denied the rights to use the resources they had previously relied upon. Although conservation is now shifting towards a more participatory approach, research gaps still exist in determining the meaning of 'the environment' and the role of local means of conservation in rural communities in South Africa. This study focused on children's cultural environmental narratives from two rural villages in the Eastern Cape, South Africa. Children from grades 4, 7 and 10 were involved in the study, and adult family members, local experts and village elders were included in the study to allow for comparison between children's and adult's narratives and to realise what Local Ecological Knowledge (LEK) was being passed on. This thesis considers children's use of the environment for play and their sense of place as key methods in ascertaining children's environmental narratives and perceptions. At both field sites, local experts and community elders possessed a wealth of cultural environmental narratives, but these narratives were not necessarily being passed on. Changing household structures and other socio-economic factors influence cultural environmental practices, which in turn have an impact on the cultural environmental narratives being passed down. In many cases, parents' safety fears strongly impacted upon children's access to the environment, resulting in gendered environmental knowledge. The study compared differing vegetation types and degrees of environmental access. The differing environments produced similar cultural environmental narratives, leading to new understandings in community environment relationships. Children living near the state administered forest had significantly less environmental knowledge, bringing about questions of sustainable bio-cultural diversity in the future. The recognition of cultural environmental values is especially important in the rural areas of South Africa, where unemployment and increased poverty levels have led to greater dependence on natural resources for social, economic and cultural purposes. It is proposed that local cultural environmental narratives and landscape perceptions be included into community conservation and environmental education policies and programmes to provide local solutions to the problem of biodiversity conservation in local contexts.
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Date Issued: 2011

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Ill at ease in our translated world ecocriticism, language, and the natural environment in the fiction of Michael Ondaatje, Amitav Ghosh, David Malouf and Wilma Stockenström

- Johnson, Eleanore

Authors: Johnson, Eleanore
Date: 2011
Subjects: Ondaatje, Michael, 1943- The English patient Ghosh, Amitav. The hungry tide Malouf, David, 1934- An imaginary life Stockenström, Wilma. The expedition to the Baobab tree Ecocriticism Human ecology in literature Nature in literature
Language: English
Type: Thesis , Masters , MA
Identifier: vital:2234 , http://hdl.handle.net/10962/d1002277
Description: This thesis explores the thematic desire to establish an ecological human bond with nature in four contemporary novels: The English Patient by Michael Ondaatje, The Hungry Tide by Amitav Ghosh, An Imaginary Life by David Malouf, and The Expedition to The Baobab Tree by Wilma Stockenström. These authors share a concern with the influence that language has on human perception, and one of the most significant ways they attempt to connect with the natural world is through somehow escaping, or transcending, what they perceive to be the divisive tendencies of language. They all suggest that human perception is not steered entirely by a disembodied mind, which constructs reality through linguistic and cultural lenses, but is equally influenced by physical circumstances and embodied experiences. They explore the potential of corporeal reciprocity and empathy as that which enables understanding across cultural barriers, and a sense of ecologically intertwined kinship with nature. They all struggle to reconcile their awareness of the potential danger of relating to nature exclusively through language, with a desire to speak for the natural world in literature. I have examined whether they succeed in doing so, or whether they contradict their thematic suspicion of language with their literary medium. I have prioritised a close ecocritical reading of the novels and loosely situated the authors’ approach to nature and language within the broad theoretical frameworks of radical ecology, structuralism and poststructuralism. I suggest that these novels are best analysed in the context of an ecocritical mediation between poststructuralist conceptions of nature as inaccessible cultural construct, and the naïve conception of unmediated, pre-reflective interaction with the natural world. I draw especially on the phenomenological theories of Maurice Merleau-Ponty, whose insistence that perception is always both embodied and culturally mediated truly renders culture and nature irreducible, intertwined categories. By challenging historical dualisms like mind/body and culture/nature, the selected novels suggest a more fluid and discursive understanding of the perceived conflict between language and nature, whilst problematizing the perception of language as merely a cultural artefact. Moreover, they are examples of the kind of literature that has the potential to positively influence our human conception of nature, and adapt us better to our ecological context on a planet struggling for survival.
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Date Issued: 2011

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Randomization in a two armed clinical trial: an overview of different randomization techniques

- Batidzirai, Jesca Mercy

Authors: Batidzirai, Jesca Mercy
Date: 2011
Subjects: Clinical trials -- Statistical methods , Biometry , Sampling (Statistics)
Language: English
Type: Thesis , Masters , MSc (Biostatistics and Epidemiology)
Identifier: vital:11781 , http://hdl.handle.net/10353/395 , Clinical trials -- Statistical methods , Biometry , Sampling (Statistics)
Description: Randomization is the key element of any sensible clinical trial. It is the only way we can be sure that the patients have been allocated into the treatment groups without bias and that the treatment groups are almost similar before the start of the trial. The randomization schemes used to allocate patients into the treatment groups play a role in achieving this goal. This study uses SAS simulations to do categorical data analysis and comparison of differences between two main randomization schemes namely unrestricted and restricted randomization in dental studies where there are small samples, i.e. simple randomization and the minimization method respectively. Results show that minimization produces almost equally sized treatment groups, but simple randomization is weak in balancing prognostic factors. Nevertheless, simple randomization can also produce balanced groups even in small samples, by chance. Statistical power is also improved when minimization is used than in simple randomization, but bigger samples might be needed to boost the power.
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Date Issued: 2011

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Hierarchical spatial organization and prioritization of wetlands: a conceptual model for wetland rehabilitation in South Africa

- Sieben, E J J, Ellery, William F N, Kotze, Donovan C, Rountree, M

Authors: Sieben, E J J , Ellery, William F N , Kotze, Donovan C , Rountree, M
Date: 2011
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/144399 , vital:38342 , DOI: 10.1007/s11273-011-9212-8
Description: Wetland rehabilitation planning needs to take into account many different aspects of the wetland and its context. In South Africa, much emphasis is placed on the delivery of ecosystem services, poverty relief and skills development for those involved in labour-intensive rehabilitation measures. A framework is presented that facilitates decision-making with regards to wetland rehabilitation planning. This starts with prioritizing which wetlands need attention within a catchment. This is followed by decisions regarding which rehabilitation measures would be effective in improving certain ecosystem services based upon the aims of rehabilitation and the social context of the surrounding catchment.
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Date Issued: 2011

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Perceptions of school managers regarding knowledge sharing practices in the FET (Grade 10-12) schools in the butterworth District

- Mkabile, Bulelwa

Authors: Mkabile, Bulelwa
Date: 2011
Subjects: School principals -- Education (FET) -- Schools
Language: English
Type: Thesis , Masters , M Ed
Identifier: vital:18440 , http://hdl.handle.net/11260/d1007249
Description: Education reforms and the constant changes in the curriculum require school managers and educators to keep abreast of the changes and developments. In order to achieve quality education in this Information Age, there is a need to share knowledge, resources, and good practices and ensure twinning of schools. The purpose of this study was to explore perceptions, beliefs and experiences of school managers regarding knowledge sharing in schools. Qualitative methods were used to collect and analyse the data. In accordance with the qualitative approach, a phenomenological design was adopted. Data was gathered through interviews from a sample of six school managers of Further Education and Training (Grade 10 -12) schools. The findings of the study revealed that school managers perceive their role as important for the success of knowledge sharing in schools. They attribute the good performance in their schools to the educators‟ willingness to share knowledge. However, trust, good relations and respect determined the willingness to share and with whom to share knowledge in schools. School managers believe that availability of Information and Communication Technology (ICT) infrastructural resources could improve knowledge sharing practices in schools. Staff meetings, subject meetings, workshops and notice boards were identified as some of the strategies currently used for sharing knowledge. The support of the district officials and other education specialists has contributed in helping schools deal with education reforms. Communities of practice are recommended in order to improve and encourage the sharing of tacit and implicit knowledge in schools. Researchers believe that professional communities of practice enhance sharing and provide greater opportunities for knowledge creation. Policy developers, curriculum planners and district officials need to develop and adopt creative and innovative strategies to ensure effective distribution and sharing of knowledge and information among school managers and educators in schools.
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Date Issued: 2011

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An analysis of the reliability of the 22kV distribution network of the Nelson Mandela Bay Municipality

- Lamour, Bernhardt Gustave

Authors: Lamour, Bernhardt Gustave
Date: 2011
Subjects: Electrical power distribution -- Reliability -- Nelson Mandela Bay Municipality , Electric power system -- Quality control , Electrical apparatus and appliances -- Maintenance and repair
Language: English
Type: Thesis , Masters , MTech
Identifier: vital:9596 , http://hdl.handle.net/10948/1537 , Electrical power distribution -- Reliability -- Nelson Mandela Bay Municipality , Electric power system -- Quality control , Electrical apparatus and appliances -- Maintenance and repair
Description: This dissertation is a systematic study of the 22kV Nelson Mandela Bay Municipality (NMBM) electricity power distribution network reliability evaluation and improvements to be applied. Reliability evaluation of electric power systems has traditionally been an integral part of planning and operation. Changes in the electricity utility, coupled with aging electrical apparatus, create a need for more realistic techniques for power system reliability modelling. This work presents a reliability evaluation technique that combines set literature and evaluation criteria. In analysing system reliability, this research takes into account the reasons for many outages and voltage dips and seeks to find mitigating approaches that are financially justified. The study analyses the power system in terms of the methodology developed, using power system reliability techniques, power quality evaluation, protection analyses and evaluating the network against maintenance interventions and programs, manpower availability and weather conditions contributing to the outages. In evaluating the power system various techniques are used to determine if the power network operates within the NRS standards, namely, reliability calculations, testing of protection equipment, interrogation of power quality instruments and modeling the network on Digsilent. This study will look at all the important factors influencing power system reliability, analysing the network in terms of the methodology and recommend improvements.
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Date Issued: 2011

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A framework to enhance the mobile user experience in an Mlearning interaction

- Botha, Adele

Authors: Botha, Adele
Date: 2011
Subjects: Educational technology , Information technology , Educational innovations , Teaching -- Aids and devices
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:9753 , http://hdl.handle.net/10948/d1008163 , Educational technology , Information technology , Educational innovations , Teaching -- Aids and devices
Description: The new millennium is witness to a telecommunications world that is vastly different from even the recent past with developments in the mobile sector having dramatically changed the Information and Communication Technology (ICT) landscape. Mobile cellular technology has proliferated faster than any previous technology and is now the most ubiquitous technology in the world. The focus of this thesis is the development of a framework to enhance the Mobile User Experience in an Mlearning interaction. This research is contextualised by the goal-oriented use of mobile cellular technologies in a formal educational environment. As such the study, although residing in the field of Human-Computer Interaction (HCI), acknowledges issues arising in the Education Domain as a specific field of application. The aim of the research was to investigate the components of a framework to enhance the Mobile User Experience in an Mlearning interaction. The development of the framework was facilitated by the exploration of: the Mobile User Experience factors and their impact, on the Mobile User Experience of learners participating in a goal-oriented Mlearning interaction. These critical factors were documented in terms of the Mobile User Experience components, and the relationships of these components to each other as well as the Mobile User Experience of an Mlearning interaction. The research, grounded in a phenomenological research philosophy, applied an inductive reasoning approach, and was operationalised through a single case study methodology. A qualitative research strategy was considered appropriate, as the phenomenon of User Experience is linked to the hedonistic attributes of the interaction. This study was conducted in four phases with focus on three embedded units of analysis. The three units of analysis were identified as: The learner as end user in an Mlearning interaction; The educator as designer of the Mlearning interaction; and The Mlearning interaction. The research revealed that the Mobile User Experience of an Mlearning interaction is affected by the mobile user, mobile use, mobile device, mobile business practices, mobile networks, mobile interaction and mobile context. Within the Mlearning interaction the significant components are the learners as mobile users, the enhance interactions, removal of barriers to the interaction, goal-oriented nature of the interaction and the ducational context. Identifying these components and their associated Mobile User Experience factors and impacts, present the main contribution of this thesis. In conclusion, the limitations of the study are documented and topics for future research are outlined.
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Date Issued: 2011

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After Baines

- Walters, John Attwood Vereker

Authors: Walters, John Attwood Vereker
Date: 2011
Subjects: Baines, Thomas, 1820-1875 Baines, Thomas, 1820-1875 -- Biography Painting, South African -- Exhibitions Painters -- South Africa -- Biography
Language: English
Type: Thesis , Masters , MFA
Identifier: vital:2432 , http://hdl.handle.net/10962/d1004368
Description: By researching the life and work of Thomas Baines (1820 - 1875) in relation to a broader discourse of painting and the lived experience of being a 'white' male in a post-apartheid South Africa, I explore the ways in which this figure from the past has provoked the three series of artworks I have produced for my Master of Fine Art exhibition. This study has been divided into two parts, represented by the two chapters contained herein. Chapter One includes a critical retelling of Baines' biography and a discussion of the primary ways in which I have engaged with both the life and the working practice of this artist. I also address my own personal complicity in the constructions of 'the figure of Baines' as I have framed him both visually and textually during my work for this degree. Chapter Two describes some of the practicalities of my working process as a visual artist, including how I understand the theoretical and conceptual concerns which I raise in Chapter One to be visually manifest in my work. In this chapter, I also discuss my work in relation to the work of the contemporary South African artists William Kentridge and Johannes Phokela. The artistic practice of one artist imitating another artist's work is also explored as a central conceptual thread which could be seen to weave my verbal and visual production together.
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Date Issued: 2011

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