The spatial evolution of the chemotaxis proteins of the Bacillus subtilis group
- Authors: Yssel, Anna Elizabeth Johanna
- Date: 2011
- Subjects: Chemotaxis , Bacillus subtilis , Bacillus (Bacteria) , Homology (Biology) , Plants -- Microbiology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4027 , http://hdl.handle.net/10962/d1004087 , Chemotaxis , Bacillus subtilis , Bacillus (Bacteria) , Homology (Biology) , Plants -- Microbiology
- Description: The aim of this work was to study spatial evolution of the chemotaxis proteins of a group of plant-associated soil-dwelling bacteria vernacularly referred to as the B. subtilis group. This was achieved by creating homology models for the chemotaxis proteins if a suitable template was available, and by analysing the selective forces (positive, purifying or neutral) acting upon the chemotaxis proteins. Chemotaxis is the phenomenon in which bacteria direct their movement towards more favourable conditions, and is critical for processes such as obtaining nutrients, escaping toxic compounds, host colonization and bio-film formation. Members of the B. subtilis group exhibit different preferences for certain host plants, and it is therefore feasible that their chemotactic machinery are fine-tuned to respond optimally to the conditions of the various niches that the strains inhabit. Homology models were inferred for the plant growth promoting B. amyloliquefaciens FZB42 proteins CheB, CheC, CheD, CheR, CheW and CheY. The interactions between: CheC-CheD, the P1 and P2 domains of CheA with CheY and CheB, and the P4 and P5 domains of CheA with CheW were also modelled. The hydrophobic interactions contributing to intra- and inter-protein contacts were analysed. The models of the interactions between CheB and the various domains of CheA are of particular interest, because to date no structures have been solved that show an interaction between a histidine kinase (such as CheA) and a multidomain response regulator (such as CheB). Furthermore, evidence that phospho-CheB may inhibit the formation of phospho-CheY by competitively binding to the P2 domain of CheA is also presented. Proteins were analysed to determine if individual amino acid sites are under positive, neutral or purifying selection. The Methyl Accepting Chemotaxis Proteins (MCPs), CheA and CheV were also analyzed, but due to a lack of suitable templates, no homology models were constructed. Site-specific positive and purifying selection were estimated by comparing the ratios of non-synonymous to synonymous substitutions at each site in the sequences for the chemotaxis proteins as well as for the receptors McpA, McpB, and McpC. Homology models were coloured according to intensity of selective forces. It was found that the chemotaxis proteins of member of the B. subtilis group are under strong evolutionary constraints, hence it is unlikely that positive selection in these proteins are responsible for the differences in habitat preference that these organism exhibit.
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- Date Issued: 2011
Elephants, compassion, and the largesse of literature
- Authors: Wylie, Dan
- Date: 2011
- Language: English
- Type: Text
- Identifier: vital:582 , http://hdl.handle.net/10962/d1018924
- Description: [From the text] Why is it that we do not raise a monument, a mausoleum, nor even a humble gravestone, to mark the death of every elephant? We habitually, even compulsively, do this for other humans, occasionally for treasured pets. Yet we do not do it for the most charismatic, gigantic, culturally resonant land animal we will ever encounter. Why not? Some possible answers. One: too much work. Another: we regard other animals as less conscious than ourselves; we are the only creatures who deserve to have our deaths so commemorated. A third: wild animals are part of wild ecosystems; it is ‘natural’ for them to die and to be reabsorbed namelessly back into those ecosystems. We humans, on the other hand, consider ourselves somehow separate from those ecosystems: we shield ourselves from ‘Nature’ with bricks and literatures while we live, with marble and epitaphs after we die.
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- Date Issued: 2011
Post-impoundment population dynamics of non-native common carp Cyprinus Carpio in relation to two large native cyprinids in Lake Gariep, South Africa
- Authors: Winker, Henning
- Date: 2011
- Subjects: Cyprinidae -- South Africa -- Gariep Dam Carp -- South Africa -- Gariep Dam Fish populations -- South Africa -- Gariep Dam Fishes -- Physiology -- South Africa -- Gariep Dam Barbus aeneus -- South Africa -- Gariep Dam Mudfishes -- South Africa -- Gariep Dam Freshwater fishes -- South Africa -- Gariep Dam
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5311 , http://hdl.handle.net/10962/d1005156
- Description: To contribute to the understanding of the invasion biology of common carp Cyprinus carpio in southern Africa, this thesis investigated the life history, relative abundance, long-term population demographics and trophic niche utilisations of non-native common carp C. carpio in relation to two endemic cyprinids, Orange River mudfish Labeo capensis and smallmouth yellowfish Labeobarbus aeneus in South Africa‟s largest impoundment, Lake Gariep. The growth zone deposition rates in astericus otoliths of the three species were validated as biannual for C. carpio and as annual for L. capensis and L. aeneus, which allowed for reliable estimation of lengths-at-age upon which growth, age-at-maturity and mortality rates could be estimated. Cyprinus carpio exhibited fast growth, matured relatively early at two years of age and attained a maximum age of seven years. Labeo capensis grew significantly slower, but attained older ages of up to 12 years. Females showed notably delayed maturation at approximately six years of age. The life history parameter estimates for L. aeneus were similar to those of L. capensis. These species-specific life history characteristics contributed to a substantially higher population growth potential of C. carpio compared to L. capensis and L. aeneus. Delta-lognormal and delta-gamma Generalized Linear Models (GLMs) were used to analyse patterns of relative abundance of L. capensis, L. aeneus and C. carpio. The application of these GLMs was necessary to account for large proportions of zeros and strong skewness in the catch-per-unit-effort (CPUE) from experimental gillnet and fisheries-dependent angler surveys. Confidence intervals around predicted abundance indices were obtained through the development of a generalised parametric bootstrap procedure. The resulting standardised abundance indices were coupled with results from analysis of stable isotope ratios of fish tissues and potential food resources and revealed that C. carpio was mainly confined to soft-bottom habitats, where it predominantly foraged on benthic invertebrates. Labeo capensis was abundant in a wide range of benthic habitats and was consumed basal food resources such as detritus. Labeobarbus aeneus was found to feed mostly on pelagic zooplankton. There were no significant interspecific differences in trophic niche space, suggesting limited resource competition among the three species. Standardised historical and contemporary gillnet CPUE data indicated slow population growth rates of L. capensis and L. aeneus during the first ten years postimpoundment, but showed high biomass levels some four decades after impoundment. These results could be corroborated by stochastic age-structured production model (ASPM) simulations. In contrast to the two endemic species, the gillnet CPUE of C. carpio showed a clear „boom and bust‟ pattern, which, based on ASPM simulations, could be best explained by increased food availability during the first five years postimpoundment, followed by suboptimal conditions thereafter. Together, these results provided evidence that the establishment of the C. carpio population did not prevent the slow but successful long-term establishment of the two large endemic cyprinids. Both endemic fishes revealed specialised feeding within the impoundment.
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- Date Issued: 2011
A comparative analysis of the intermediary systems in South Africa, Namibia, Zimbabwe and Ethiopia
- Authors: Wilkerson, Tendai Marowa
- Date: 2011
- Subjects: Juvenile courts -- South Africa , Juvenile courts -- Namibia , Juveline courts -- Zimbabwe , Juvenile courts -- Ethiopia , Children -- Legal status, laws, etc. -- South Africa , Children -- Legal status, laws, etc. -- Namibia , Children -- Legal status, laws, etc. -- Zimbabwe , Children -- Legal status, laws, etc. -- Ethiopia , Child witnesses -- South Africa , Child witnesses -- Namibia , Child witnesses -- Zimbabwe , Child witnesses -- Ethiopia , Mediation -- Law and legislation -- South Africa , Mediation -- Law and legislation -- Namibia , Mediation -- Law and legislation -- Zimbabwe , Mediation -- Law and legislation -- Ethiopia , Children's rights -- South Africa , Children's rights -- Namibia , Children's rights -- Zimbabwe , Children's rights -- Ethiopia
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3698 , http://hdl.handle.net/10962/d1003213 , Juvenile courts -- South Africa , Juvenile courts -- Namibia , Juveline courts -- Zimbabwe , Juvenile courts -- Ethiopia , Children -- Legal status, laws, etc. -- South Africa , Children -- Legal status, laws, etc. -- Namibia , Children -- Legal status, laws, etc. -- Zimbabwe , Children -- Legal status, laws, etc. -- Ethiopia , Child witnesses -- South Africa , Child witnesses -- Namibia , Child witnesses -- Zimbabwe , Child witnesses -- Ethiopia , Mediation -- Law and legislation -- South Africa , Mediation -- Law and legislation -- Namibia , Mediation -- Law and legislation -- Zimbabwe , Mediation -- Law and legislation -- Ethiopia , Children's rights -- South Africa , Children's rights -- Namibia , Children's rights -- Zimbabwe , Children's rights -- Ethiopia
- Description: Prior to 1990, very few countries in the world offered special protection to child witnesses interfacing with the justice system. There were no legal provisions permitting testimonial accommodations for children in court. The courtroom experience was significantly traumatic for the children. With the international focus shifting from protecting and upholding the rights of the accused in the courtroom towards a more victim-centred approach, various international and regional instruments have strongly dvocated that children deserve special protection because of their vulnerability. In order for the courts to be able to elicit accurate evidence from the child without further traumatizing the child, research has shown that the child needs assistance. An intermediary may be defined as a person who facilitates communication between the child and the courtroom in a manner that takes into account the child‟s cognitive and developmental limitations. The thesis was prompted by the need to make a contribution to the currently limited body of literature on the intermediary systems in South Africa, Namibia, Zimbabwe and Ethiopia by investigating how the systems can be improved and sustained in a way that helps to protect the child witness in court. Despite the problems the South African courts have had in identifying the appropriate interpretation of its intermediary legislation, the country emerges as a clear leader for the steps it took by creating a positive legal framework within which child protection issues are addressed and introducing the concept of the intermediary. This concept proved to be an inspiration to its neighbours, Namibia and Zimbabwe. The influence of the South African intermediary legislation is evident in the Namibian and Zimbabwean legislation. Although Namibian legislators have drafted laws that permit intermediary assistance in court, there are as yet no intermediaries appointed. In Ethiopia, although there is no discernible intermediary legislation, the country has managed to establish an intermediary system. As a result of the analysis conducted, it is evident that the efficacy of the intermediary system is dependent on the presence of an enabling legislation, its clarity and ease of interpretation, the sensitisation of court role players on child vulnerabilities, the significance of intermediary assistance, and finally a government's commitment towards the implementation process.
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- Date Issued: 2011
Vocabulary development in a grade 7 class using dictionary skills: an action research project
- Authors: Wells, Stephanie Alice
- Date: 2011
- Subjects: English language -- Study and teaching (Elementary) -- South Africa -- Eastern Cape Vocabulary -- Study and teaching (Elementary) -- South Africa -- Eastern Cape English language Dictionaries -- Polyglot -- Study and teaching (Elementary) -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1822 , http://hdl.handle.net/10962/d1003708
- Description: As I was involved as a voluntary, part-time teacher in a local, semi-rural school in the Eastern Cape, South Africa, I became increasingly aware of the learners' lack of English literacy. I therefore decided to do a practical research on vocabulary development, focusing on dictionary skills. In this thesis I describe how I implemented a vocabulary development programme as an Action Research project. My research group was a grade 7 class of English First Additional Language learners who had minimal exposure to English at school and in their communities. The class was a mixture of Afrikaans and isiXhosa home language speakers and the medium of instruction was Afrikaans. The school served a low-income community and was poorly resourced. As dictionary skills is a requirement of the national curriculum, I used 10 time-tabled lessons over a 5 week period to introduce the learners to dictionaries. My data sources were a journal detailing my reflections on each lesson; a video-recording of the lessons; small group interviews after each lesson which were audio-recorded; tasksheets on the work covered in class and questionnaires asking the learners for written responses to the lessons. The class teacher who filmed the lessons was also asked for feedback during and after the programme. My goals were to assess my teaching approach in these circumstances and to what extent the outcomes were positive for the learners. As I had come from a background of English Home Language teaching in good, well-resourced schools I found I had to question many of my assumptions. Although I was an experienced, qualified and confident teacher, I was continually having to reassess my teaching methods which were being challenged by very different classroom conditions. The outcomes of the research show why I was not able to achieve what I had thought I could in the time given.
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- Date Issued: 2011
Bayesian logistic regression models for credit scoring
- Authors: Webster, Gregg
- Date: 2011
- Subjects: Bayesian statistical decision theory Credit scoring systems Regression analysis Logistic regression analysis Monte Carlo method Markov processes Financial institutions
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:5574 , http://hdl.handle.net/10962/d1005538
- Description: The Bayesian approach to logistic regression modelling for credit scoring is useful when there are data quantity issues. Data quantity issues might occur when a bank is opening in a new location or there is change in the scoring procedure. Making use of prior information (available from the coefficients estimated on other data sets, or expert knowledge about the coefficients) a Bayesian approach is proposed to improve the credit scoring models. To achieve this, a data set is split into two sets, “old” data and “new” data. Priors are obtained from a model fitted on the “old” data. This model is assumed to be a scoring model used by a financial institution in the current location. The financial institution is then assumed to expand into a new economic location where there is limited data. The priors from the model on the “old” data are then combined in a Bayesian model with the “new” data to obtain a model which represents all the available information. The predictive performance of this Bayesian model is compared to a model which does not make use of any prior information. It is found that the use of relevant prior information improves the predictive performance when the size of the “new” data is small. As the size of the “new” data increases, the importance of including prior information decreases
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- Date Issued: 2011
An investigation into knowledge and change in a Grade 9 environmental research project
- Authors: Webber, Susan Marion
- Date: 2011
- Subjects: Environmental education -- Activity programs -- South Africa Environmental education -- Evaluation -- South Africa Environmental education -- Study and teaching (Secondary) -- South Africa Sustainable development -- Evaluation -- South Africa Sustainable development -- Study and teaching (Secondary) -- South Africa Active learning -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1597 , http://hdl.handle.net/10962/d1003479
- Description: This study considers a Grade 9 Integrated Environmental Research Project which was implemented as a vehicle to induce knowledge-based change in learners. It was noted that change did not occur as hoped, and this study was undertaken to review the Grade 9 Project in order to improve it and to probe the apparent gap between knowledge and action. The study generated evidence on the learning processes within the project. This revealed a number of contradictions and tensions which limit change initiatives within the local environment. Notable here was a contradictory mandate between undertaking a research-based change project and responding to the rubric of assessment which was not linked to the research done. It was found that faced with this dual mandate, learners chose to focus on the assessment-laden mandate as this was the ultimate agenda that would reap the reward within the traditional school environment. The study examines the gap between knowledge and practice to probe ways in which to close this gap in the context of an environmental research assignment. The outcome is a recommendation that we as the project designers review the evidence of tensions and contradictions revealed in the study to reflect on the underlying purpose of the project and reshape it in light of recent literature on the challenges of social learning and change.
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- Date Issued: 2011
After Baines
- 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
Stewardship as an educational process of social learning and change: two case studies conducted in the Western Cape
- Authors: Walker, Clara Isabella
- Date: 2011
- Subjects: Environmental education -- South Africa -- Western Cape Conservation of natural resources -- South Africa -- Western Cape Natural resources -- South Africa -- Western Cape -- Management Social learning -- South Africa -- Western Cape Sustainable development -- South Africa -- Western Cape Cape Nature Stewardship Programme (South Africa) Biodiversity Stewardship Programme (South Africa)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1772 , http://hdl.handle.net/10962/d1003657
- Description: Stewardship in South Africa, as it is being implemented within the framework of the Biodiversity Stewardship Programme (BSP), is an attempt by conservation agencies to engage landowners in the voluntary securing of parcels of biodiverse land, through signing a contract for a certain time period, not to develop the landscape in ways that will impact negatively on the biodiversity of the area in question. The focus of this study is the relationship between biodiversity stewardship and social learning, as I hope to ascertain how stewardship practices are helping to resolve the current problems of biodiversity loss in the Western Cape. The overall aim of this research is to gain an understanding of how, in its capacity as a conservation education process, the Cape Nature Stewardship Programme can foster social learning amongst the landowners involved in its implementation, by leading them to a better understanding of their environmental responsibilities. Data was generated through the use of interviews and informal discussions with participants together with document analysis, such as brochures, pamphlets and presentations. My approach to the analysis of my data was two-phased. In the first phase, I analysed the data generated from the interview process and from reviewing the documents the stewardship officials supplied me with. The second phase involved looking into the results of the two case studies, and formulating analytical statements which were then used to review the case evidence within a social learning perspective, derived from Wals (2007). In constructing an analytical framework for the interpretation of my data, I drew heavily on Wals' (2007) notion of social learning occurring in sequential activities. I used this insight as a lens through which to trace the educational effects of the implementation of the CNSP in the two case study areas.The research highlighted evidence that Stewardship initiatives should be based on the foundation of social learning and invest time and effort in building an environmental knowledge capital amongst the landowners involved. By equipping them with these necessary conservation skills, one creates a 'community of practice' where those individuals adopt a sustainability habitus contributing towards a change and environmental understanding and practises in field.
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- Date Issued: 2011
The nexilitas factor: host-guest relationships in small owner managed commercial accommodation facilities in contemporary South Africa
- Authors: Von Lengeling, Volkher Heinrich Christoph
- Date: 2011
- Subjects: Hospitality industry -- South Africa Interpersonal relations Social interaction Liminality Consumer behavior Home-based businesses -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2093 , http://hdl.handle.net/10962/d1002656
- Description: The commercialization of hospitality established arguably the oldest profession. Historically small commercial hospitality establishments, known as inns in the western world, were of ill repute. Perhaps connected to their reputation, this category of accommodation facility has been seriously neglected as an area of academic inquiry, particularly from the perspective of the host. While there has been a huge growth in the interdisciplinary field of tourism studies in recent decades, little attention has been paid to the role of the host in the host-guest relationship at whatever level of analysis. This thesis seeks to redress the balance. Hospitality is a basic form of social bonding. This type of bonding, where a hierarchy between strangers is implicit (as with hosts and guests), may be termed ‘nexilitas’; nexilitas is a form of social bonding in liminal circumstances. To that extent it is comparable to ‘communitas’ which describes social bonding between equals in certain liminal circumstances. The difference is that nexilitas is a form of bonding between individuals in a complex power relationship. The host controls the hospitality space, but custom also empowers the guest with certain expectations, especially in the commercial context. The thesis identifies the various forms of hospitality – traditional ‘true’ or ‘pure’ hospitality, social hospitality, cultural hospitality and commercial hospitality – and discusses these critically in their historical and cross-cultural contexts, with emphasis on the perspective of the host. The passage of hospitality is then traced through the three phases of preliminality, liminality and post-liminality and discussed along the themes anticipation, arrival and accommodation and finally departure of the guest. While the historical and ethnographic review is mainly based on written histories and the experiences of other anthropologists as guests as well as ethnographers, the passage of hospitality draws on the multi-sited auto-anthropological experiences of the author, both as host and as ethnographer of contemporary South African hosts in small owner-managed commercial hospitality establishments.
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- Date Issued: 2011
Perceptions and constructions of cholera in the Eastern Province Herald and Daily Dispatch, 1980-2003
- Authors: Van Zyl, Kylie
- Date: 2011
- Subjects: Daily Dispatch (East London, South Africa) Eastern Province Herald (Port Elizabeth, South Africa) Journalism -- South Africa -- 20th century Journalism -- South Africa -- 21st century Cholera -- Reporting -- South Africa Epidemics -- Reporting -- South Africa Mass media -- Moral and ethical aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2566 , http://hdl.handle.net/10962/d1002419
- Description: While the growing literature on South Africa’s healthcare and epidemics has often mentioned cholera in passing, there is as yet little academic work dedicated to it. This thesis addresses that deficit by examining the causes, spread and extent of cholera in South Africa between 1980 and 2003. Furthermore, it examines cholerarelated coverage in two newspapers, the Daily Dispatch and the Eastern Province Herald to determine how cholera and people with cholera were represented, and show how changes in the coverage of two major epidemics between 1980 and 2003 exemplify the political transition in South Africa, reflect changing political ideologies and reveal the shifting role of media within this period. The thesis argues three main points. Firstly, that representations of cholera and those who were sick with cholera were based on long-standing tropes connecting disease, class and ‘race’. Secondly, that policy-making based on these tropes influenced the unfair distribution and quality of health resources along racial lines, resulting in cholera outbreaks during the apartheid era. Failure to address these inequities post-apartheid, and the replacement of racial bias with discrimination on the grounds of socioeconomic development, resulted in further cholera outbreaks. Thirdly, using Alan Bell’s newspaper-discourse analysis framework to examine cholera-related articles the thesis compares and contrasts apartheid and postapartheid coverage in the two newspapers. This analysis reveals that during the 1980s the coverage was uncritical of the government’s handling of the epidemic or of its racially-discriminatory healthcare system. The newspapers uncritically accepted government-employed medical professionals as the final authorities on the epidemic, excluding alternative viewpoints. The coverage also “blamed the victim”, constructing affected “black” groups as potential threats to healthy “white” communities. Conversely, post–1994 coverage was criticised the government’s handling of the epidemic and the state of the public healthcare system. Government-employed medical professionals or spokespeople were not accepted as incontestable authorities and a range of sources were included. The coverage also shifted blame for the outbreaks to the government and its failure to address public health service delivery and rural development problems. The thesis shows the historical threat to the health of communities posed by uncaring governments.
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- Date Issued: 2011
Quantifying crop damage by Grey crowned crane balearica regulorum regulorum and evaluating changes in crane distribution in the North Eastern Cape, South Africa
- Authors: Van Niekerk, Mark Harry
- Date: 2011
- Subjects: Cranes (Birds) -- South Africa -- Eastern Cape , Cranes (Birds) -- Geographical distribution -- South Africa -- Eastern Cape , Cranes (Birds) -- Behavior -- South Africa -- Eastern Cape , Cranes (Birds) -- Food -- South Africa -- Eastern Cape , Corn -- Effect of grazing on -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5749 , http://hdl.handle.net/10962/d1005436 , Cranes (Birds) -- South Africa -- Eastern Cape , Cranes (Birds) -- Geographical distribution -- South Africa -- Eastern Cape , Cranes (Birds) -- Behavior -- South Africa -- Eastern Cape , Cranes (Birds) -- Food -- South Africa -- Eastern Cape , Corn -- Effect of grazing on -- South Africa -- Eastern Cape
- Description: Complaints of crop damage by cranes on planted maize in the North Eastern Cape, South Africa, have been increasing since the mid-1990‘s, and in some instances severe losses have been reported. Crop damage by the Grey Crowned Crane Balearica regulorum regulorum near the town of Maclear (31º04´S 28º22´E), has been quantified over two growing seasons, and assessed relative to losses caused by foraging Cape Crows Corvus capensis and other feeding damage assumed to be caused by insects. Twelve fields were selected based on previous patterns of crop depredation. Maize seed in seven of the fields was treated with the chemical ‗Gaucho‘ and five fields were planted with untreated maize. In order to determine the source of losses, twenty quadrats (4 m x 4 m) randomly distributed within each field were visited on average every second day, for a period of up to twenty eight days. Results indicate that seed treatments do act as a deterrent to feeding by both cranes and crows, however crane damage is generally insignificant compared to other sources of damage. My study also reviewed past sightings data of the Grey Crowned Crane in an effort to determine if the conversion of former grassland to plantations in this region may have increased foraging activity in maize fields. The data did not allow for clear-cut conclusions regarding changes in distribution or population trends. Conclusions provide direct input into the management of agricultural areas by enabling landowners to take steps to mitigate crop damage. These mitigation measures may either involve the application of seed treatments, or the planting of low risk crops in high risk areas. Future studies should consider the ppossible detrimental effects of chemical seed treatments on crane biology.
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- Date Issued: 2011
The use of learning support materials in the rural schools of Maputaland, Kwa-Zulu Natal
- Authors: Van der Merwe, Michelle
- Date: 2011
- Subjects: Environmental education -- South Africa -- Maputaland African Coelacanth Ecosystem Programme Coelacanthiformes -- South Africa -- Maputaland Teaching -- Aids and devices -- South Africa -- Maputaland Environmental education -- Curricula -- South Africa -- Maputaland
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1815 , http://hdl.handle.net/10962/d1003701
- Description: The African Coelacanth Ecosystem Programme (ACEP) was established in 2002 after the discovery of a colony of coelacanths off the Maputaland coast at Sodwana Bay, KwaZulu Natal. The environmental education and awareness sub-programme developed learning support materials (LSM's) for use in schools and the materials were disseminated annually through teacher education workshops. This study aimed to uncover the use of these LSM's in the rural schools of Maputaland. The active learning framework was used to analyse the materials. Collectively, the ACEP materials cover a range of active learning aspects; however alignment with the curriculum has resulted in an increased focus on experiments, accompanied by a loss of environmental content and a narrowing scope for active environmental learning. Workshop questionnaires and four school case studies revealed the patterns of practice of use of materials in schools. The stated use of materials by teachers is not fully realized in the actual classroom practice which centres on learning content and concept definitions. There is no culture of use of materials in the schools following the annual introduction of ACEP materials. It was also found that the marine and coastal knowledge holding power is outside the realm of the teachers' practice and control. The findings of this study come at a time when there is uncertainty over the future of South African education and the curriculum. This research may inform the environmental education and coastal and marine education field as to their role in education and more specifically the development of learning support materials.
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- Date Issued: 2011
An analysis of sources and predictability of geomagnetic storms
- Authors: Uwamahoro, Jean
- Date: 2011
- Subjects: Ionospheric storms Solar flares Interplanetary magnetic fields Magnetospheric substorms Coronal mass ejections Space environment Neural networks (Computer science)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5451 , http://hdl.handle.net/10962/d1005236
- Description: Solar transient eruptions are the main cause of interplanetary-magnetospheric disturbances leading to the phenomena known as geomagnetic storms. Eruptive solar events such as coronal mass ejections (CMEs) are currently considered the main cause of geomagnetic storms (GMS). GMS are strong perturbations of the Earth’s magnetic field that can affect space-borne and ground-based technological systems. The solar-terrestrial impact on modern technological systems is commonly known as Space Weather. Part of the research study described in this thesis was to investigate and establish a relationship between GMS (periods with Dst ≤ −50 nT) and their associated solar and interplanetary (IP) properties during solar cycle (SC) 23. Solar and IP geoeffective properties associated with or without CMEs were investigated and used to qualitatively characterise both intense and moderate storms. The results of this analysis specifically provide an estimate of the main sources of GMS during an average 11-year solar activity period. This study indicates that during SC 23, the majority of intense GMS (83%) were associated with CMEs, while the non-associated CME storms were dominant among moderate storms. GMS phenomena are the result of a complex and non-linear chaotic system involving the Sun, the IP medium, the magnetosphere and ionosphere, which make the prediction of these phenomena challenging. This thesis also explored the predictability of both the occurrence and strength of GMS. Due to their nonlinear driving mechanisms, the prediction of GMS was attempted by the use of neural network (NN) techniques, known for their non-linear modelling capabilities. To predict the occurrence of storms, a combination of solar and IP parameters were used as inputs in the NN model that proved to predict the occurrence of GMS with a probability of 87%. Using the solar wind (SW) and IP magnetic field (IMF) parameters, a separate NN-based model was developed to predict the storm-time strength as measured by the global Dst and ap geomagnetic indices, as well as by the locally measured K-index. The performance of the models was tested on data sets which were not part of the NN training process. The results obtained indicate that NN models provide a reliable alternative method for empirically predicting the occurrence and strength of GMS on the basis of solar and IP parameters. The demonstrated ability to predict the geoeffectiveness of solar and IP transient events is a key step in the goal towards improving space weather modelling and prediction.
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- Date Issued: 2011
"Too tired to speak?": investigating the reception of Radio Grahamstown's Lunchtime Live show as a means of linking local communities to power
- Authors: Tsarwe, Stanley Zvinaiye
- Date: 2011
- Subjects: Community radio -- South Africa -- Grahamstown Radio broadcasting -- South Africa -- Grahamstown Radio journalism -- South Africa -- Grahamstown Mass media -- Political aspects -- South Africa -- Grahamstown Grahamstown (South Africa) -- Economic conditions -- 21st century Grahamstown (South Africa) -- Social conditions -- 21st century Civil society -- South Africa -- Grahamstown Political participation -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3488 , http://hdl.handle.net/10962/d1002943
- Description: This study sets out to investigate Lunchtime Live, a twice-weekly, one-hour long current affairs show broadcast on a small community radio station, Radio Grahamstown, to understand its role in the local public sphere, and its value in helping civil society’s understanding of and involvement in the power structures and political activities in Grahamstown. Lunchtime Live seeks to cultivate a collective identity and promote public participation in the public affairs of Grahamstown. As a key avenue of investigation, this study seeks to test theory against practice, by evaluating Lunchtime Live’s aspirations against the audiences’ perception of it. This investigation uses qualitative content analysis of selected episodes of recorded transcripts of the shows that aired between August 2010 and March 2011, together with the audiences’ verbalised experiences of this programme through focus group discussions. The study principally uses qualitative research informed by reception theory. The research reveals three key findings. First, that resonance rather than resistance is the more dominant ‘stance’ or ‘attitude’ towards the content of Lunchtime Live. Residents interviewed agreed that the programme is able to give a “realistic” representation of their worldview, and thus is able to articulate issues that affect their lives. Second, that whilst the programme is helping establish links between members of the civil society as well as between civil society and their political representatives, residents feel that local democracy is failing to bring qualitative improvements to their everyday lives and that more ‘participation’ is unlikely to change this. Most respondents blame this on a lack of political will, incompetence, corruption and populist rhetoric by politicians who fail to deliver on the mantra of ‘a better life for all’ in the socioeconomic sphere. The study finds a scepticism and even cynicism that participatory media seems to be able to do little to dilute. Thirdly, in spite of the largely positive view about Lunchtime Live’s capacity to be a platform for public engagement, its participatory potential is structurally constrained by the material privations of most of its listeners. Given that in order to participate in talk shows and discussions audience members have to phone in, economic deprivation often precludes this. It is clear from this research that despite shows such as Lunchtime Live that are exploring new techniques of popular involvement, the voice of the ordinary people still struggles to be heard.
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- Date Issued: 2011
The design and synthesis of multidentate N-heterocyclic carbenes as metathesis catalyst ligands
- Authors: Truscott, Byron John
- Date: 2011
- Subjects: Carbenes (Methylene compounds) , Heterocyclic compounds , Ligands , Ligands -- Design , Metathesis (Chemistry) , Catalysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4304 , http://hdl.handle.net/10962/d1004962 , Carbenes (Methylene compounds) , Heterocyclic compounds , Ligands , Ligands -- Design , Metathesis (Chemistry) , Catalysis
- Description: This study has focused on the design and preparation of bi– and tridentate N–Heterocyclic Carbene (NHC) ligands in order to investigate the effect of a multidentate approach to the formation, stability and catalytic activity of coordination complexes. Chapters 1 – 3 provide background information of relevant catalysis, carbene and coordination chemistry, followed by previous work performed within our research group. In Chapter 4 attention is given to the synthetic aspects of the research conducted, comprising two distinct approaches to the preparation of unsymmetrical saturated and unsaturated NHCs. Firstly, an investigation of the saturated NHC ligands yielded three novel, unsymmetrical pro–ligands, viz., two halopropyl imidazolinium salts and a bidentate hydroxypropyl imidazolinium salt. Secondly, eight imidazolium salts have been generated, including a hydroxypropyl analogue and novel decyl and tridentate malonyl derivatives. These compounds were prepared using microwave–assisted methodology for the alkylation of N– mesitylimidazole – an approach that drastically reduced reaction times (from 8 hours – 7 days to ca. 0.5 – 2 hours) and facilitated isolation of the imidazolium salts. Many of the compounds prepared in this study are novel and were fully characterized using HRMS and 1– and 2–D NMR analysis. Coordination studies using a selection of the prepared pro–ligands afforded an alkoxy–NHC silver derivative and four novel Ru–complexes, viz., Grubbs II–type Ru–complexes containing:– chloropropyl imidazolinylidene; propenyl imidazolylidene; and bidentate alkoxypropyl imidazolylidene ligands. Furthermore, a well–defined benzyl mesitylimidazolylidene Ru–complex has been isolated, which exhibited good stability in air. DFT–level geometry–optimization studies, using the Accelrys DMol3 package have given valuable insights into the likely geometries of the prepared and putative catalysts.
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- Date Issued: 2011
A case study of the strategic leadership displayed by Kevin Hedderwick at Famous Brands between 2004-2009
- Authors: Tom, Lubabalo Alexander
- Date: 2011
- Subjects: Hedderwick, Kevin Famous Brands Leadership -- South Africa Case studies Strategic planning -- South Africa Case studies Corporate culture -- South Africa Case studies Organizational behavior -- South Africa Case studies Financial management -- South Africa Case studies Food industry and trade -- South Africa Case studies
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:772 , http://hdl.handle.net/10962/d1003893
- Description: Research studies and the review of academic literature has found that strategic leadership had a direct impact on organisational climate, and that climate in turn accounted for nearly one third of the financial results of organisations (Goleman, 2000). The conclusion from research conducted across 13 industries established that over a 20 year period, leadership accounted for more variations in performance than any other variable (Northouse, 2006). This thesis confines its research to a case study on Famous Brands. Famous Brands is currently one of Africa’s leading Quick Service Restaurant and Casual Dining franchisors and is also represented in the United Kingdom. The Group also has a manufacturing arm and supplies its franchisees, the retail trade and the broader hospitality industry with a wide range of meat, sauce, bakery, ice cream, fruit juice and mineral water products. At the time when the company’s name changed from Steers Holdings to Famous Brand in 2004, Kevin Hedderwick was appointed as Chief Operating Officer. The research examines how Kevin Hedderwick has exercised strategic leadership and thereby influenced Famous Brands’ performance. Hedderwick displays qualities, attributes and behaviours that are characterized by the phenomenon of “strategic leadership”. A quantitative analysis of Famous Brands financial performance (between 2005 and 2009) was undertaken. Further qualitative descriptions were used to further give meaning to the financial results. The success experienced by Famous Brands since Hedderwick’s appointment, seem to suggest that strategic choices and initiatives have been met with great success. The research is presented in the form of a case study that can be developed into a teaching case to be used in the classroom to illustrate the exercise of strategic leadership. The researcher explored a qualitative research framework by collecting and assimilating data from available documentation, and from a formal interview that was conducted with Mr Hedderwick. Information was also obtained from interviews that were conducted with other senior executives and influential personnel. This research concludes that the success of organisations is dependent on the interventions of a strategic leader who displays a specialist set of skills and behaviours. These strategic leaders have the ability to successfully influence their employees, thereby creating an enabling environment for the implementation of their strategic choices.
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- Date Issued: 2011
Dryland conservation areas, indigenous people, livelihoods and natural resource values in South Africa: the case of Kgalagadi Transfrontier Park
- Authors: Thondhlana, Gladman
- Date: 2011
- Subjects: Human ecology -- Kgalagadi Transfrontier Park (Botswana and South Africa) Arid regions biodiversity conservation -- Kgalagadi Transfrontier Park (Botswana and South Africa) Arid regions agriculture -- Kgalagadi Transfrontier Park (Botswana and South Africa) Indigenous peoples -- Ecology -- Kgalagadi Transfrontier Park (Botswana and South Africa) Natural resources conservation areas -- Kgalagadi Transfrontier Park (Botswana and South Africa) Natural resources -- Government policy -- Kgalagadi Transfrontier Park (Botswana and South Africa) Natural resources -- Kgalagadi Transfrontier Park (Botswana and South Africa) -- Management
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4777 , http://hdl.handle.net/10962/d1011732
- Description: Contemporary conservation and development understanding in both policy and academic circles espouses that natural resources have a significant contribution to the livelihoods of local people and that knowledge of this can better foster conservation policies that are consistent with livelihood and ecological needs. This thesis is based on research conducted in the southern Kalahari region, South Africa among the San and Mier communities bordering Kgalagadi Transfrontier Park. It looks at the importance of natural resources to the San and Mier community groups and ascertains the extent of resource use and its value within broader livelihood portfolios. It also focuses on the cultural values of natural resources and interactions among institutions and actors and how these shape natural resource governance and livelihood outcomes. Overall, natural resources represent an important livelihood source contributing up to 32 % and 9 % of the total income of the San and Mier respectively or up to 46 % and 23 % if livestock incomes are included. However, the dependence on, diversification patterns and distribution of natural resource income vary substantially between and within the two communities. With regards to the cultural values attached to natural resources by the San and Mier, the findings show that these arise from an incredibly diverse and sometimes conflicting array of values that punctuate the two communities’ way of life and they are inextricably linked to resource use. Lastly, governance of natural resources in the co-managed Park and communitymanaged resettlement farms is characterised by complex institutional arrangements, compounded by the existence of multiple actors that have multiple and sometimes conflicting objectives – as shaped by different meanings and interpretations of natural resources. Heightened inter- and intra-community conflicts are common, notably resource use conflicts between the San and Mier and between the San ‘modernist’ and ‘traditionalist’ groups. This demonstrates that the communities’ livelihood dynamics in general and the dependence on natural resources in particular, are closely linked with ecological, economic and social factors including history, culture and present livelihood needs. By exploring the social-environment interactions, the study highlights the complexities and diversity of resource use for livelihoods that should be taken into consideration for both conservation and development policy interventions and research. The main argument of the study is that the contribution of natural resources to local livelihood portfolios in co- and community-managed areas, can be better understood through a consideration of cultural dynamics and institutional arrangements since these condition natural resource access, value and use.
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- Date Issued: 2011
The contribution made by Mr Justice EF Watermeyer to South African tax jurisprudence
- Authors: Thackwell, Robert Colin
- Date: 2011
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: vital:881 , http://hdl.handle.net/10962/d1001635
- Description: The objective of this thesis is to highlight the colossal contributions made by the late Justice Watermeyer to South African tax jurisprudence. His contributions are viewed from a practical application point of view as well as from a statutory interpretative perspective. The style and technique with which he delivered his judgments are also considered to be a contribution in their own right. The core of this thesis is the analysis of seven of Justice Watermeyer‟s most influential judgments. The development and application of the principle or principles developed in each of these seven judgments is then traced chronologically through case law up until recent judgments. It is most notable that each and every phrase contained in section 11(a) of the Income Tax Act has been interpreted by Justice Watermeyer. These interpretations are still viewed as correct statements of the applicable law and will continue to be referred to on a regular basis given the fact that section 11(a) is one of the most widely contested provisions in the Income Tax Act. Several references to his approach to statutory interpretation are made through the course of the case analyses. Whilst significant evidence of a purposive oriented approach to interpretation appears in some judgments, such evidence is lacking in others. An absolute or conclusive submission in terms of his approach to statutory interpretation is not sufficiently supported. His style of judgment is also referred to and commented on, with particular focus placed on his use of illustrative examples. The contribution to South African tax law by Justice Watermeyer is found to be nothing short of enormous. He was and continues to be influential with respect to section 11(a),the definition of gross income in section 1, common law principles of tax avoidance as well as the interpretation of statutory laws of tax avoidance. It is anticipated that some of his interpretations with respect to statutory rules of tax avoidance will be referred to when the relatively new anti-avoidance provisions become the subject of litigation.
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- Date Issued: 2011
An interpretative phenomenological analysis of the experiences of HIV-positive lay counsellors working in the voluntary counselling and testing settings
- Authors: Teng, James Wei Jie
- Date: 2011
- Subjects: HIV-positive persons Peer counseling Health counseling Health counselors -- Mental health Hiv-positive persons -- Counseling of HIV-positive persons -- Mental health HIV infections -- Psychological aspects Lay analysis (Psychoanalysis)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3070 , http://hdl.handle.net/10962/d1002579
- Description: The purpose of this study was to present and understand the experiences of HIV-positive lay counsellors working in Voluntary Counselling and Testing (VCT) settings. Specifically exploring and understanding the utilisation of personal experiences within counselling encounters, the practice of peer counselling within VCT, and the challenges experienced by HIV-positive lay counsellors within VCT settings. This study, employing a qualitative interpretative phenomenological methodology required a small sample of practicing HIV-positive lay counsellors, who were selected and interviewed on their experiences utilising semi-structured interviewing. Data was analysed for meaning units, which were interpreted inductively and hermeneutically, and categorised into super-ordinate themes. Three superordinate themes within the participants’ experiences of providing VCT services were determined, namely: ‘diagnosis and disclosure experiences’, ‘peer counselling’, and ‘challenges’. This research found that the experiences of providing peer counselling depended upon identification with their client’s negative appraisal of their diagnosis experiences. Whether through empathic connections generated through the shared experience of discovering a seropositive status, or through countertransferential reactions induced through their client’s yearning for care and support. This required the counsellor to selfdisclose within counselling encounters in order to provide personal experiences of living with HIV/AIDS. Successful implementation of peer counselling provided recently diagnosed individuals with knowledge surrounding HIV/AIDS, coping skills to manage the daily physiological and psychological challenges, facilitation and adherence to treatment, social assistance, ongoing relationships, inspiring hope, and the creation of positive appraisals. However the informal utilisation of task-shifting within lay healthcare cadres, and the lack of governmental recognition for the emotional labour provided within VCT indicated that HIVpositive lay counsellors require ongoing training, support and remuneration to limit potential occupational stress, resignation, and burnout.
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- Date Issued: 2011