Localisation of Theiler's Murine Encephalomyelitis virus non-structural proteins 2B, 2C, 2BC and 3A in BHK-21 cells, and the effect of amino acid substitutions in 2C on localisation and virus replication
- Authors: Murray, Lindsay
- Date: 2007
- Subjects: Encephalomyelitis -- Genetic aspects , Amino acid sequence , Picornaviruses , Viruses -- Reproduction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4090 , http://hdl.handle.net/10962/d1007722 , Encephalomyelitis -- Genetic aspects , Amino acid sequence , Picornaviruses , Viruses -- Reproduction
- Description: The picornavirus family includes significant human and animal viruses such as poliovirus (PV), human rhinovirus (HRV) and foot-and-mouth-disease virus (FMDV). Current disease treatment and control strategies are limited by an incomplete understanding of the interactions between the non-structural, replicative picornavirus proteins and host cell components. To investigate these interactions, Theiler's murine encephalomyelitis virus (TMEV) 2B, 2C, 2BC and 3A proteins were transiently expressed in BHK-21 cells and detected by indirect immunostaining and laser-scanning or epifluorescence microscopy. The signal of the 2B protein overlapped with that of the ER marker protein, ERp60, as well as that of the peripheral Golgi marker protein, β-COP. The 2C protein overlapped with ERp60 in a faint reticular stain, and localised to large punctate structures that partially overlapped with β-COP at higher levels of expression. The 2BC protein located to large perinuclear structures that overlapped exclusively with β-COP. The TMEV 3A protein signal overlapped with both ERp60 and β-COP stains, in addition in cells expressing the 3A protein the ER appeared swollen and bulbous while the Golgi was dispersed in some cells. 2C and 2BC proteins with C-terminal deletions localised in the same manner as the wild type proteins indicating that the localisation signals that determine subcellular localisation of the proteins are within the N-terminal 60 amino acids of the 2C protein. The significance of the high degree of conservation of the N-terminal domain of the 2C protein throughout the Picornaviridae was investigated through the introduction of amino acid substitution mutations at highly conserved residues in the N-terminal domain of 2C into the viral cDNA. Upon transfection of the viral RNA into BHK-21 cells, it was observed that substitution of amino acid residues 8, 18 and 29 abolished the ability of TMEV to induce cytopathic effect (CPE), while substitution of residues 4, 14 and 23 only attenuated the ability of TMEV to induce CPE. To determine whether amino acid substitution mutations would affect the localisation of the 2C protein, 2C proteins with substitution mutations at amino acids 4, 8, 14, 18, 23 and 29 were transiently expressed in BHK-21 cells and detected by indirect imrnunostaining and examination by laser-scanning confocal and epifluorescence microscopy. The 2C mutant 4, 8 and 29 proteins showed slightly altered localisation patterns compared to the wild type protein with a significant portion of the proteins localising in a perinuclear stain suggesting possible localisation to the nuclear envelop. The 2C mutant 14 and 18 proteins localised to a diffuse pattern in BHK-21 cells while the 2C mutant 23 protein located to small punctate structures that partially overlapped with the ERp60 stain but were completely separate from the β-COP stain. Finally, a hydrophilic, antigenic region of the 2C protein was expressed in frame with an N-terminal GST tag and was successfully purified on a pilot-scale and detected by Western analysis. This 2C178 peptide will be used to generate antibodies against the 2C and 2BC proteins for use in future studies. This study has furthered our knowledge of the localisation of the picornavirus 2B, 2C, 2BC and 3A proteins in host cells and identified a possible link between this localisation and an ability of TMEV to replicate in BHK-21 cells.
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Making visual literacy meaningful in a rural context: an action research case study
- Authors: Mbelani, Madeyandile
- Date: 2007
- Subjects: Visual literacy -- Study and teaching (Secondary) -- South Africa -- Eastern Cape -- Case studies Education -- Research -- Case studies Education -- Research -- South Africa -- Eastern Cape Rural schools -- Research -- Case studies Rural schools -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1668 , http://hdl.handle.net/10962/d1003551
- Description: This thesis reports on a collaborative action research case study into the teaching of visual literacy to Grade 10 learners in a rural high school in the Eastern Cape, South Africa. Visual literacy is one of the critical aspects that have been incorporated in the teaching of English First Additional Language as required by the National Curriculum Statement (Grade 10-12), which has been implemented in Grade 10 as from 2006. With the aim of improving learners’ performance in visual literacy I designed a visual literacy unit that consisted of lesson plans running over 7 periods in 10 school days. In implementing the unit the learners were first grouped and then exposed to visual grammar and visual texts and then they critically viewed such texts and designed their own. Data was collected daily in the form of individual learner journals, researcher’s journal/diary, and copies were kept of activities done by learners (individually or in groups). Also, two teachers were invited as non-participant observers to each visit a lesson. Learner focus groups were conducted and critical friends were interviewed, tape recorded and transcribed. A camera was used to take still photographs to show learner activities in groups and during group presentations. The data revealed that visual literacy could be taught meaningfully in a rural high school as the learners could identify, cut, paste and discuss elements of visual language and they finally designed their own advertisements in groups. In the analysis of data the following factors emerged as hindrances for successful teaching of visual literacy in a rural high school: lack of resources; learners’ lack of a foundation in visual literacy from Grades 7-9; and problems revolving around time management and pacing. As action research comes in spirals, this research represented the first one and the researcher found the study an eye opener and a foundation to build on in the second spiral (that is not part of this research).
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Measuring the RFI environment of the South African SKA site
- Authors: Manners, Paul John
- Date: 2007
- Subjects: Radio telescopes , Radio telescopes -- South Africa , Radio astronomy , Radio astronomy -- South Africa , Square Kilometer Array (Spacecraft) , Radio -- Interference -- Measurement
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5474 , http://hdl.handle.net/10962/d1005259 , Radio telescopes , Radio telescopes -- South Africa , Radio astronomy , Radio astronomy -- South Africa , Square Kilometer Array (Spacecraft) , Radio -- Interference -- Measurement
- Description: The Square Kilometre Array (SKA) Project is an international effort to build the world’s largest radio telescope. It will be 100 times more sensitive than any other radio telescope currently in existence and will consist of thousands of dishes placed at baselines up to 3000 km. In addition to its increased sensitivity it will operate over a very wide frequency range (current specification is 100 MHz - 22 GHz) and will use frequency bands not primarily allocated to radio astronomy. Because of this the telescope needs to be located at a site with low levels of radio frequency interference (RFI). This implies a site that is remote and away from human activity. In bidding to host the SKA, South Africa was required to conduct an RFI survey at its proposed site for a period of 12 months. Apart from this core site, where more than half the SKA dishes may potentially be deployed, the measurement of remote sites in Southern Africa was also required. To conduct measurements at these sites, three mobile measurement systems were designed and built by the South African SKA Project. The design considerations, implementation and RFI measurements recorded during this campaign will be the focus for this dissertation.
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Mores, fault and fides: are these acceptable criteria when income tax deductions are claimed
- Authors: Swanepoel, Marius G
- Date: 2007
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:889 , http://hdl.handle.net/10962/d1001643
- Description: The two “pillars” on which taxable income is based are the definition of “gross income” in section 1 of the Income Tax Act, 58 of 1962, and the “general deduction formula” comprising the preamble to section 11, section 11(a) and section 23(g) of the Act. Many of the terms used in these sections are not defined in the Income Tax Act. Case law in relation to these sections reveals that morality issues, the negligence of taxpayers and the good faith of taxpayers have from time to time been treated as relevant considerations by the courts, both abroad and in South Africa, in allowing or disallowing deductions from the gross income of taxpayers. In some instances this occurred apparently unwittingly. In other instances, earlier decisions were followed without a thorough consideration of the correctness of the underlying reasoning or of the criteria which were applied in the earlier decisions. In relation to the definition of “gross income”, however, fides, mores and fault have not been a consideration. In CIR v Delagoa Bay Cigarette Co Ltd 1918 TPD 391 Bristowe, J stated: “I do not think it is material for the purpose of this case whether the business carried on by the company is legal or illegal.” There were a number of cases heard in relation to income from illegal activities (for example, COT v G, 1981 (4) SA 167 (ZA), 43 SATC 159, and ITC 291, 7 SATC 335, which related to the misappropriation of funds, ITC 1545, 54 SATC 464, which dealt with the proceeds of the sale of stolen diamonds and ITC 1624, 59 SATC 373, which dealt with overcharging customers). In these cases, the question turned on whether or not the amounts were received by the taxpayers for their own benefit and therefore to be included in gross income, or whether the taxpayers incurred a concomitant liability to repay the amounts, and did not involve the question of fides, mores or fault. The research concludes that, providing an even-handed approach is applied to both income and expense considerations, fides and mores may continue to play a role as a useful yardstick in this context. However, that fault, particularly the causal negligence of taxpayers in the process of sustaining a loss or incurring expenditure whilst conducting their income generating operations, has effectively been jettisoned as an irrelevant consideration, is a salutary development which has contributed to legal certainty.
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Nguni fermented foods: working with indigenous knowledge in the Life Sciences: a case study
- Authors: Hanisi, Nosipho
- Date: 2007
- Subjects: Life sciences -- Study and teaching (Secondary) -- South Africa -- Case studies Environmental education -- South Africa -- Case studies Fermented foods -- Case studies Fermentation Indigenous peoples -- Case studies Nguni (African people) -- Social life and customs. Xhosa (African people) -- Social life and customs. Ethnoscience
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1957 , http://hdl.handle.net/10962/d1008372
- Description: This study examines learning interactions around indigenous ways of knowing associated with fermented grain foods (the making of umqombothi) and the concept of alcoholic fermentation in the Grade 11 Life Sciences curriculum. As an environmental education study it also investigates the cultural significances of the fermented grain food and how learners might make better lifestyle choices. The inclusion of indigenous ways of knowing in the Life Sciences curriculum (FET band) created spaces and opportunities for the use of both knowledge's in sociocultural context and the structured propositions of the learning area in order to construct knowledge. This stimulated learners' understanding of fermentation and also led to a valuing of social context as well as the cultural capital embedded in the indigenous ways of knowing. The study suggests that parental involvement contributed to this valuing of intergenerational ways of knowing. Learners also deliberated how colonial interpretations of Nguni culture and the religious beliefs of Christians had served to marginalise and foster a widening urban rejection of isiXhosa cultural practices related to fermented foods. In their learning and discussion, learners developed new insights and respect for isiXhosa fermentation practices (ukudidiyela) that bring out the food value and nutrition in the grain. The data illustrates that lesson activity that drew on relevant Learning Outcomes and Assessment Standards to integrate Indigenous Knowledge practices in a Life Sciences learning programme, served to enhance learner understanding of alcoholic fermentation. They also document a revaluing of cultural heritage and learners bringing up the problem of alcohol abuse in the community. Curriculum work with Indigenous Knowledge thus not only assisted learners to grasp the science but to use this alongside a valued cultural knowledge capital to deliberate and act on a local concern.
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Occult forces -- lived identities: witchcraft, spirit possession and cosmology amongst the Mayeyi of Namibia's Caprivi Strip
- Authors: Von Maltitz, Emil Arthur
- Date: 2007
- Subjects: Yeye (African people) , Yeye (African people) -- Namibia -- History , Occultism -- Namibia , Witchcraft -- Namibia , Spirit possession -- Namibia , Cosmology
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2121 , http://hdl.handle.net/10962/d1013279
- Description: Around Africa there seems to be an increasing disillusion with 'development', seen under the rubric of teleological 'progress', which is touted by post-colonial governments as being the cure for Africa's ailments and woes. Numerous authors have pointed out that this local disillusion, and the attempt to manage the inequities that arise through development and modernity, can be seen to be understood and acted upon by local peoples through the idiom of witchcraft beliefs and fears (see Geschiere & Fisiy 2001; Geschiere 1997; Nyamnjoh 2001; Comaroff & Comaroff 1993; Ashforth 2005) and spirit possession nanatives (see Luig 1999; Gezon 1999), or more simply, occult beliefs and praxis (Moore & Sanders 2001). The majority of the Mayeyi of Namibia's Eastern Caprivi perceive that development is the only way their regiOn and people can survive and succeed in a modernising world. At ~he same time there is also a seeming reluctance to move towards perceiving witchcraft as a means of accumulation (contra Geschiere 1997). This notion of the 'witchcraft of wealth' is emerging, but for the most part witches are seen as the enemies of development, while spirit possession narratives speak to the desire for development and of the identity of the group vis-a-vis the rest of the world. The thesis presented argues that, although modernity orientated analyses enable occult belief to be used as a lens through which to 1..mderstand 'modernity's malcontents' (Comaroff & Comaroff 1993), they can only go so far in explaining the intricacies of witchcraft and spirit possession beliefs themselves. The dissertation argues that one should return to the analysis of the cosmological underpinnings of witchcraft belief and spirit possession, taken together as complementary phenomena, in seeking to understand the domain of the occult. By doing so the thesis argues that a more comprehensive anthropological understanding is obtained of occult belief and practice, the ways in which the domain of the occult is constituted and the ways in which it is a reflection or commentary on a changing world.
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Opportunities for eco-efficiency at Summerpride Foods Ltd.: a pineapple processing factory
- Authors: Venters, Bruce Russell Ainsley
- Date: 2007
- Subjects: Summerpride Foods Ltd. (South Africa) Environmental protection -- South Africa Industries -- Environmental aspects -- South Africa Pineapple industry -- South Africa Environmental policy -- South Africa Sustainable development -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:787 , http://hdl.handle.net/10962/d1003908
- Description: International awareness and demands for the protection of the environment by the public on industry has only been pushed into the limelight in the past couple of decades. Prior to this it could be argued that it was accepted that environmental protection and economic development were at odds. However it has since been recognised that there is a need to achieve environmental sustainability, the concept of which was released in the 1987 Brundtland Report released by the United Nations. There are a number of ways that industry can reduce its impact on the environment and thus help reach this goal. While some advocated that stricter legislation would result in greater innovation by industry in “cleaning-up” its act, such as the Porter Hypothesis, there were also a number of new concepts and voluntary industry codes being developed. These new practices and codes have been promoted by organisations such as the International Chamber of Commerce and include technological improvements within organisations and improved resource productivity. The aim of this case study research was to find out what the environmental policy and related performance of Summerpride Foods Ltd, a pineapple processing factory in East London was and does an understanding of its environmental performance provide insights for improved efficiency. This involved the identification and analysis of what resources were used during the processing of pineapples as well as making recommendations that would result in increased efficiencies of their use. Due to the number of resources identified, only the use of water and coal which were ranked as having the highest impact were investigated further. The literature review showed that there are industry moves to applying cleaner production and eco-efficiency concepts as a means to attaining environmental sustainability. There are a number of voluntary environmental management system standards and codes that organisations can subscribe to with most probably the ISO 14001 standard being the most internationally recognised. There are many benefits to organisations adopting such standards. The use of lifecycle assessments is a useful tool that can be used to assess the environmental impact of a product through its entire life and thus enable one to identify all resources used and their impact, as well as to provide the information required to quantify areas where the greatest improvements can be made. The results of this research showed that at the start of the study, there was no formal environmental policy in place at Summerpride Foods Ltd and that this was starting to become a requirement with some customers. The detailed results which focused on water and coal usage showed that current operating methods do not recognise the importance of any wastage and that there are a number of changes that could be made that would not only result in better efficiency of use but would also result in substantial financial savings to the organisation. Summerpride Foods Ltd currently has a number of systems in place that help reduce its impact on the environment but these are not formally recorded. Summerpride Foods Ltd should adopt the principles of eco-efficiency and record all systems that impact on the environment. This would be the first step to attaining a formal environmental management system accreditation which due the increasing competitiveness of the international market in which Summerpride Foods Ltd operates, would give it a degree of advantage over those competing pineapples processing factories that do not have such accreditation.
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Particle precipitation effects on the South African ionosphere
- Authors: Sibanda, Patrick
- Date: 2007
- Subjects: Ionosphere -- South Africa , Precipitation (Chemistry) -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5481 , http://hdl.handle.net/10962/d1005267 , Ionosphere -- South Africa , Precipitation (Chemistry) -- South Africa
- Description: Particle precipitation involves the injection of energetic particles into the ionosphere which could increase the ionisation and conductivity of the upper atmosphere. The goal of this study was to examine the ionospheric response and changes due to particle precipitation in the region over South Africa, using a combination of groundbased and satellite instruments. Particle precipitation events were identified from satellite particle flux measurements of the Defence Meteorological Satellite Program (DMSP). Comprehensive studies were done on the events of 5 April, 2000 and 7 October, 2000. Analysis of the data from the satellite instruments indicates that no particle precipitation was observed over the South African region during these events and that it is unlikely to occur during other such events. To validate the data, methods and tools used in this study, precipitation in the South Atlantic anomaly (SAA) region is used. Satellite ion density measurements revealed that strong density enhancements occurred over the SAA region at satellite altitudes during the precipitation events, but this did not occur in the South African region. The measurements also revealed how the ionisation enhancements in the SAA region correlated with geomagnetic and solar activities. Particle precipitation and convective electric fields are two major magnetospheric energy sources to the upper atmosphere in the auroral and the SAA regions. These increase dramatically during geomagnetic storms and can disturb thermospheric circulation in the atmosphere and alter the rates of production and recombination of the ionised species. Ionosonde observations at Grahamstown, South Africa (33.30S, 26.50E), provided the data to build a picture of the response of the ionosphere over the South African region to particle precipitation during the precipitation events. This analysis showed that, within the confines of the available data, no direct connections between particle precipitation events and disturbances in the ionosphere over this region were revealed.
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Past trauma, anxious future a case-based evaluation of the Ehlers and Clark model for PTSD applied in Africa
- Authors: Van der Linde, Francois
- Date: 2007
- Subjects: Cognitive therapy Post-traumatic stress disorder -- Africa Rape trauma syndrome -- Treatment -- Africa Rape victims -- Africa Anxiety -- Treatment Depression, Mental -- Treatment Post-traumatic stress disorder -- Patients Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3075 , http://hdl.handle.net/10962/d1002584
- Description: This research report documents the therapeutic intervention undertaken with a 23-year-old Swazi rape victim. The format of this research report takes the form of a case study that follows the principles proposed by Fishman (2005). Its aim is to document the treatment process of an individual of African decent in order to establish whether the treatment model can be effective in clinical settings and in contexts and cultural settings different from that in which it was developed. The Ehlers and Clark (2000) cognitive therapy model for post-traumatic stress disorder (PTSD) was utilised to assess, conceptualise, and treat the case. The client entered therapy three years after being raped for a third time. The case formulation identified factors maintaining the disorder as well as how other traumatic and abusive events earlier in her life influenced her response to the rapes. Data consisted off audio-tape recordings and detailed written synopses of each assessment and therapy session, psychometric measurement instruments and self-report scales completed throughout the intervention, material written by the client, and a research interview conducted by an independent party. She was treated for PTSD and comorbid depression over a period of five months in accordance with the principles described by Ehlers and Clark and a narrative of the treatment process was written. The case narrative in conjunction with quantitative data suggested that this model assisted the client in initiating a healing process. As such the model was found to be both effective and transportable to an African context. Various points of discussion are highlighted, including the challenges of working with PTSD and comorbid major depression, the client-therapist relationship, and that a client and therapist from different cultures, backgrounds, and with different home languages can work together effectively using the Ehlers and Clark model.
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Population structure, growth and recruitment of two exploited infralittoral molluscs (Haliotis midae and Turbo sarmaticus) along the south east coast, South Africa
- Authors: Proudfoot, Lee-Anne
- Date: 2007
- Subjects: Abalones -- South Africa , Abalones -- Growth -- South Africa , Turbinidae -- South Africa , Mollusks -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5744 , http://hdl.handle.net/10962/d1005430 , Abalones -- South Africa , Abalones -- Growth -- South Africa , Turbinidae -- South Africa , Mollusks -- South Africa
- Description: The two most frequently exploited species along the south east coast of South Africa are the gastropods, Haliotis midae (abalone) and Turbo sarmaticus (alikreukel). H. midae is a high valued commercial species, and suffers intense levels of illegal fishing. T. sarmaticus however, has no commercial value but is the preferred food item for impoverished subsistence communities. Owing to the fact that no legal commercial fishery exists for either species along the south coast, very few studies have been undertaken, especially in the heavily exploited infralittoral. Infralittoral size frequency distributions for both species revealed significant variation in density and size among sites of varying exploitation pressure. Densities ranged between 0 – 2.23 m⁻² (H. midae) and 0.03 – 4.93 m⁻² (T. sarmaticus) and maximum shell lengths ranged from 49.4 – 153.5 mm (H. midae) and 28.3 – 104.4 mm (T. sarmaticus). Relatively high densities and large sizes were found in marine reserves and secluded areas, and low densities and small sizes at sites near to large population centres and within the former Ciskei homeland region. Mean size of the largest 10% of the population, total density and sexually mature density were significantly related to exploitation predictors for both species. In addition, densities of H. midae juveniles were significantly related to exploitation predictors, suggesting that recruitment may be suppressed at the most exploited sites. Exploitation of T. sarmaticus tended to be localized with refuge and subtidal populations persisting. H. midae exploitation was however, far more extensive and intense. Growth of H. midae was investigated using three methods; mark-recapture, cohort analysis and growth banding analysis at Kowie Rocks, Port Alfred. The most useful of these methods for determining growth was a new technique described for growth banding analysis; which was validated using cohort analysis and measurements of shells of known age. This technique was less time consuming and labour intensive than previously described methods. Abalone growth was best described by the Schnute (1981) growth function. Systematic geographic variation in growth was observed for 10 sites along the South African coastline. Significant differences in growth among sites existed for animals between 0-4 years (P < 0.0001) and 4-6 years (P < 0.0001), and in the mean maximum sizes attained (P < 0.001). In general, abalone from the south east/east coast were found to have faster growth rates, smaller mean maximum sizes and attained sexual maturity earlier than those along the south west/ west coast. Haliotis midae recruit and juvenile densities were found to differ significantly among sites of varying exploitation pressure (P < 0.0001) and among months for recruit densities (P < 0.001). Exploited sites had low recruit and juvenile densities compared to unexploited sites and peak recruitment occurred during October/ November 2005. Recruit densities were significantly related to infralittoral adult densities during two of the three sampling months (P<0.05), when recruitment was low. No relationship was observed during the period of high recruitment, with all sites receiving high recruit densities. It was concluded that variation in recruit densities was the result of a combination of both density-dependent relationships (i.e. local spawner density and temporal variability in recruitment intensity) and the possible dispersal capabilities of H. midae. In addition, it was concluded that at present recruitment overfishing was not occurring along the south east coast. Post-recruitment mortality rates were variable but relatively constant, with hypothetical percentage survival and density curves revealing high rates and similar mortality curves among sites. Variation in juvenile densities was consequently a result of initial recruit densities and not variation in post-recruitment mortality. T. sarmaticus populations were found to be regionally sustainable and persisted along the south east coast due to adjacent intertidal and subtidal refuge populations. However, H. midae populations are becoming decimated along the south east coast. From the information obtained in this study new management proposals were suggested and discussed, such as closed areas and region-based management fisheries together with stock enhancement. These suggestions may prove to be feasible alternatives to present management strategies.
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Pricing exotic options using C++
- Authors: Nhongo, Tawuya D R
- Date: 2007
- Subjects: C++ (Computer program language) , Monte Carlo method , Simulation methods , Options (Finance) -- Mathematical models , Pricing -- Mathematical models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5577 , http://hdl.handle.net/10962/d1008373 , C++ (Computer program language) , Monte Carlo method , Simulation methods , Options (Finance) -- Mathematical models , Pricing -- Mathematical models
- Description: This document demonstrates the use of the C++ programming language as a simulation tool in the efficient pricing of exotic European options. Extensions to the basic problem of simulation pricing are undertaken including variance reduction by conditional expectation, control and antithetic variates. Ultimately we were able to produce a modularized, easily extend-able program which effectively makes use of Monte Carlo simulation techniques to price lookback, Asian and barrier exotic options. Theories of variance reduction were validated except in cases where we used control variates in combination with the other variance reduction techniques in which case we observed increased variance. Again, the main aim of this half thesis was to produce a C++ program which would produce stable pricings of exotic options.
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Public sector industrial relations in the context of alliance politics: the case of Makana Local Municipality, South Africa (1994-2006)
- Authors: Makwembere, Sandra
- Date: 2007
- Subjects: Makana Municipality , South African Municipal Workers Union , African National Congress , Cosatu , South African Communist Party , Local government -- South Africa -- Eastern Cape , Industrial relations -- South Africa -- Eastern Cape , Labor unions -- South Africa , South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3301 , http://hdl.handle.net/10962/d1003089 , Makana Municipality , South African Municipal Workers Union , African National Congress , Cosatu , South African Communist Party , Local government -- South Africa -- Eastern Cape , Industrial relations -- South Africa -- Eastern Cape , Labor unions -- South Africa , South Africa -- Politics and government -- 1994-
- Description: This thesis is in the field of Industrial Relations. It concerns a micro-level investigation of the dynamics of public sector industrial relations in post-apartheid South Africa. It focuses on the Tripartite Alliance between the African National Congress (ANC), the South African Communist Party (SACP) and the Congress of South African Trade Unions (COSATU) and explores what the Alliance relationship has meant for the traditional roles of employees and their representatives on the one hand, and employers and their representatives on the other. The thesis examines the political, organisational and societal contradictions and implications for COSATU public sector union affiliates and their members in their relationship to the ANC as an ally (via the Alliance) and the context in which ANC members form part of management (in government). The South African Municipal Workers’ Union (SAMWU) was used as an archetype of a COSATU public sector union affiliate that engages with the State as employer at the municipal level. It is a case study of Makana Local Municipality (Eastern Cape Province, South Africa) using qualitative research techniques and content analysis to derive the relevant information. The author conducted a series of in-depth interviews of key informants and observations at Makana Local Municipality were done. Based on the empirical data obtained from the investigation, the thesis argues that the traditional roles in the employment relationship at the workplace have been affected by the political alliance. Industrial relations roles have become increasingly vague especially since many within local government share ANC/SACP memberships with members of the trade union. The study also highlights that within an increasingly globalising post-apartheid environment, the Alliance provides mixture of benefits and challenges for workplace negotiations and employment relations in ways that macro-level analyses of employer-employee relationships do not always capture.
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Reading the Sowetan's mediation of the public's response to the Jacob Zuma rape trial: a critical discourse analysis
- Authors: Stent, Alison
- Date: 2007
- Subjects: Zuma, Jacob -- Trials, litigation etc Zuma, Jacob -- Public opinion Sowetan (Johannesburg, South Africa) Populism -- South Africa Social choice -- South Africa Social justice -- South Africa Ethnicity -- Political aspects -- South Africa Rape -- Public opinion Women -- Crimes against -- South Africa Sex discrimination against women -- South Africa Trials (Rape) -- South Africa Rape in mass media Crime and the press -- South Africa Mass media and women -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3485 , http://hdl.handle.net/10962/d1002940
- Description: In this minithesis I conduct a critical discourse analysis to take on a double-pronged task. On the one hand I explore the social phenomenon of the contestation between supporters of then-ANC deputy president Jacob Zuma and supporters of his rape accuser. The trial, which took place in the Johannesburg High Court between mid-February and early May 2006, stirred intense public interest, both locally and internationally. The performance of thousands of Zuma’s supporters and a far smaller number of gender rights lobby groups, both of whom kept a presence outside the court building throughout the trial, received similar attention. Second, I examine how the Sowetan, a national daily tabloid with a black, middle-class readership, mediated the trial through pictures of the theatre outside the court and letters to the editor. The study is informed by post-Marxist and cultural studies perspectives, both approaches that are concerned with issues of power, ideology and the circulation of meaning within specific sociocultural contexts. A rudimentary thematic content analysis draws out some of the main themes from the material, while the critical discourse analysis is located within a theoretical framework based on concepts from Laclau & Mouffe’s theory of meaning, which assumes a power struggle between contesting positions seeking to invalidate one another and to either challenge or support existing hegemonies. This is further informed by, first, Laclau’s theorisation of populism, which assumes that diverse groupings can unite under a demagogue’s banner in shared antagonism towards existing power, and second, by concepts from Mamdani’s theorisation of power and resistance in colonial and post-colonial Africa, which explicates three overarching ideological discourses of human rights, social justice and traditional ethnic practices. The study, then, explores how these three discourses were operationalised by the localised contestations over the trial.
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Relating indigenous knowledge practices and science concepts : an exploratory case study in a secondary school teacher-training programme
- Authors: Mandikonza, Caleb
- Date: 2007
- Subjects: Ethnoscience -- Study and teaching (Secondary) -- Zimbabwe Science -- Study and teaching (Secondary) -- Zimbabwe Teachers -- Training of -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1918 , http://hdl.handle.net/10962/d1007321
- Description: This study reports research on how student teachers in Science at Mutare Teachers' College in Zimbabwe worked with indigenous knowledge practices in relation to science concepts in the secondary school syllabus. The study was conducted among first-year science students and involved them in developing science learning activities for a peer-teaching process that was part of their course. The research was undertaken during a review ofthe college syllabus and as a study to inform the Secondary Teacher Training Environmental Education Programme (ST²EEP). The research design involved the researcher in participant observations and interviews with rural people to document indigenous knowledge practices and to develop materials for the students to work with in the lessons design part of the study. The student teachers used the documented practices to generate learning activities and lesson plans to teach the science concepts they had identified. A peer review session and focus group interviews followed the lesson presentations. Findings from the research point to the rural community being a repository of diverse indigenous knowledge practices. Student teachers showed that they had prior knowledge of both indigenous knowledge practices and science concepts when they come to class. Student teachers were able to relate indigenous knowledge practices and science concepts in ways that have the potential to enhance the learning of science in rural school contexts that lack laboratories and science equipment. The scope of the study does not allow for anything beyond tentative conclusions that point to the need for further work to be undertaken with student teachers and for the research to be extended to teaching and learning interactions in schools. Recommendations are also made for further resource-based work to be undertaken within the forthcoming St²eep implementation phase in 2007.
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Reviewing the use of environmental audits for environmental learning in school contexts: a case study of environmental auditing processes within a professional development course
- Authors: Hoffmann, Patricia Anne
- Date: 2007
- Subjects: Environmental auditing -- Study and teaching -- South Africa -- Case studies Environmental education -- South Africa -- Case studies Sustainable development -- Study and teaching -- South Africa -- Case studies Professional education -- South Africa -- Case studies Teachers -- Training of -- South Africa -- Case studies Educational change -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1746 , http://hdl.handle.net/10962/d1003630
- Description: This case study focuses on the use of environmental audits for learning, by teachers participating in the Schools and Sustainability professional development course in Durban, South Africa. It reviews ways in which audits were choreographed and used for lessons within school contexts. It explores ways in which audits shaped meaning-making interactions and environmental learning processes. This is an interpretive case study, characterized by a moderate realist perspective. Data were generated through interviews with teachers, field observations, photographs, document analysis, and group interviews with learners. Data were analyzed using the general comparative method. The research takes place in the context of educational transformation in South Africa. Some of the challenges accompanying the shift to Outcomes Based Education seem to be associated with naïve interpretations of constructivism and a view of reality as socially constructed and relative. This seems to have influenced ways in which audits are being undertaken in school contexts. This study argues that a realist orientation to auditing may be a more useful process for engaging with the world and enhancing the way learners perceive and respond to environmental risk. Ideas about reality-congruence and the interacting processes of involvement and detachment are of central importance in understanding processes of knowledge construction and meaning making in this study. The study draws on the work of Elias (1987) and Latour (1999) to shed light on the significance of auditing processes in which a close engagement with reality, coupled with a measure of detachment, can lead to the construction of a more reality-congruent account and a more realistic assessment of the environmental issue in focus. Key findings of the study suggest that the effectiveness of environmental auditing as a pedagogical process was influenced by the teachers’ intentions, knowledge and skills, choreography of the audit, nature of the teaching and learning interactions, and ways in which teachers and learners engaged with the findings. The study recommends that auditing activities should be carefully structured and mediated by teachers to be meaningful and to enable learners to identify environmental issues, gather data, engage in critical reflection and deliberate appropriate responses for social and environmental transformation.
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Roles : "I am as intently observed as the people photograph"
- Authors: Pelser, Monique Myren
- Date: 2007
- Subjects: Hugo, Pieter Portrait photography Self-portraits Photography, Artistic -- Philosophy
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2457 , http://hdl.handle.net/10962/d1007647
- Description: With this dissertation I propose an investigation of how the photographic portrait attempts to construct and confirm identity through the representation of types. Drawing from theoretical texts by Roland Barthes and Robert Sobieszek and engaging with my own process of self-portraiture, as a means of troubling the usual power relations involved between the photographer and the sitter, I will demonstrate the dialectical nature of these roles involved in photographic portraiture. Looking at Pieter Hugo's portraits of judges in Botswana permits me to deal with issues of masquerade and how fashions and uniforms mask an individual allowing him/her to perform roles and stereotypes in society. Referring to another set of Hugo's images from his ongoing series Looking Aside, I will explore the paradoxical nature of the portrait through the dialectic of the 'self 'and 'other' subject and object split through an exploration of notions of skin and prosthetic skin and the relationship to the liminal space 'opened' between subject and object, or viewer and image.
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Satellite television use among Zimbabwean professionals : an investigation into audience consumption of SABC Africa's '60 Minutes live in Africa'
- Authors: Mugoni, Petronella Chipo
- Date: 2007
- Subjects: Direct broadcast satellite television -- Zimbabwe Television viewers -- Zimbabwe Television viewers -- Zimbabwe -- Case studies Television broadcasting of news -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3512 , http://hdl.handle.net/10962/d1007707
- Description: Within the context of debates surrounding the consumption of global media by local audiences in Third World countries, this study explores the reasons behind satellite television subscription, and consumption of international news among a sample of young professional men and women in contemporary Zimbabwe. The study seeks to uncover how the research participants respond to news broadcast on SABC Africa's '60 minutes live in Africa', a programme which they can only access via satellite television in their country. Working within the frame of audience studies which insists on understanding media consumption and reception in context, this study examines how the respondents, situated within the specific Zimbabwe context, characterised as it is by serious social, economic and political challenges, respond to both regional news and news about their country on '60 minutes live in Africa'. Within the frame of qualitative research the study employs a two-stage sampling procedure and data collection strategy to uncover the factors that underpin international media consumption and reception by professional men and women situated in a country undergoing rapid change. The findings of the study point to the various social and individual factors that underlie media consumption choices as well as to the different socially patterned reasons why local audiences are either attracted to, or reject global media. The study found that SABC Africa's '60 minutes live in Africa' is more popular and better received than Western-broadcast programmes on channels such as BBC, CNN, and Sky News among Zimbabwean professionals. I also uncovered some evidence that cultural proximity and relevance are of supreme importance in determining which media audiences chose to consume and what level of engagement they bring to their reception of global media. These and other findings directly confront media models that privilege beliefs in cultural imperialism and the dominance of Western media and their effects on Third World audiences.
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Securing media streams in an Asterisk-based environment and evaluating the resulting performance cost
- Authors: Clayton, Bradley
- Date: 2007 , 2007-01-08
- Subjects: Asterisk (Computer file) , Computer networks -- Security measures , Internet telephony -- Security measures
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4647 , http://hdl.handle.net/10962/d1006606 , Asterisk (Computer file) , Computer networks -- Security measures , Internet telephony -- Security measures
- Description: When adding Confidentiality, Integrity and Availability (CIA) to a multi-user VoIP (Voice over IP) system, performance and quality are at risk. The aim of this study is twofold. Firstly, it describes current methods suitable to secure voice streams within a VoIP system and make them available in an Asterisk-based VoIP environment. (Asterisk is a well established, open-source, TDM/VoIP PBX.) Secondly, this study evaluates the performance cost incurred after implementing each security method within the Asterisk-based system, using a special testbed suite, named DRAPA, which was developed expressly for this study. The three security methods implemented and studied were IPSec (Internet Protocol Security), SRTP (Secure Real-time Transport Protocol), and SIAX2 (Secure Inter-Asterisk eXchange 2 protocol). From the experiments, it was found that bandwidth and CPU usage were significantly affected by the addition of CIA. In ranking the three security methods in terms of these two resources, it was found that SRTP incurs the least bandwidth overhead, followed by SIAX2 and then IPSec. Where CPU utilisation is concerned, it was found that SIAX2 incurs the least overhead, followed by IPSec, and then SRTP.
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Securing softswitches from malicious attacks
- Authors: Opie, Jake Weyman
- Date: 2007
- Subjects: Internet telephony -- Security measures , Computer networks -- Security measures , Digital telephone systems , Communication -- Technological innovations , Computer network protocols , TCP/IP (Computer network protocol) , Switching theory
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4683 , http://hdl.handle.net/10962/d1007714 , Internet telephony -- Security measures , Computer networks -- Security measures , Digital telephone systems , Communication -- Technological innovations , Computer network protocols , TCP/IP (Computer network protocol) , Switching theory
- Description: Traditionally, real-time communication, such as voice calls, has run on separate, closed networks. Of all the limitations that these networks had, the ability of malicious attacks to cripple communication was not a crucial one. This situation has changed radically now that real-time communication and data have merged to share the same network. The objective of this project is to investigate the securing of softswitches with functionality similar to Private Branch Exchanges (PBX) from malicious attacks. The focus of the project will be a practical investigation of how to secure ILANGA, an ASTERISK-based system under development at Rhodes University. The practical investigation that focuses on ILANGA is based on performing six varied experiments on the different components of ILANGA. Before the six experiments are performed, basic preliminary security measures and the restrictions placed on the access to the database are discussed. The outcomes of these experiments are discussed and the precise reasons why these attacks were either successful or unsuccessful are given. Suggestions of a theoretical nature on how to defend against the successful attacks are also presented.
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Securitisation and its application to low cost housing finance in South Africa
- Authors: Zimbwa, Allan Golden
- Date: 2007
- Subjects: South Africa. Constitution , Human rights -- Government policy -- South Africa , Right to housing -- South Africa , Housing -- Law and legislation -- South Africa , Housing policy -- South Africa , Low income housing -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1011 , http://hdl.handle.net/10962/d1002746 , South Africa. Constitution , Human rights -- Government policy -- South Africa , Right to housing -- South Africa , Housing -- Law and legislation -- South Africa , Housing policy -- South Africa , Low income housing -- South Africa
- Description: Section 26 of the Constitution of South Africa Act 108 of 1996 provides that housing is a basic human right and that the government must take reasonable legislative and other measures to achieve the realisation of this right. A number of measures were taken to try to resolve this socio-economic issue. A number of housing institutions were established , various pieces of legislation were passed and housing subsidies were provided. However, housing backlogs remain a challenge. In March 1994 the housing backlog was estimated between 1,3 and 1,8 million units. When more than a million houses were provided by 2001 , the housing backlog had increased to between 2 and 3 million houses. To date subsidies in excess of R29 billion have been spent on housing provision. A study by the Department of Housing concluded that, at the current rate of increase of housing funding vis-a-vis the growing backlog and rapid urbanisation, the household backlog will not be changed in ten years' time. The United States of America (USA) had a similar low cost housing problem, but securitisation alleviated it with the participation of government agencies Fannie Mae, Ginnie Mae and Freddie Mac. In South Africa, the NHFC tried to emulate the USA model by establishing Gateway Home Loans (Pty) Limited (Gateway) in 1999. Gateway, however, was not a success. This research investigates whether securitisation can be applied in South Africa to alleviate the low cost housing issue. The study finds that there is a credit availability gap for the low income sector earning less than R8 000 per month because of the perceived risk of default and unwillingness by banks to lend to this sector. The increase in housing backlog that continues unabated, inadequate housing finance system to low income earners, the lessons learnt from the failure of Gateway, the success factors of the USA securitisation model and the sound and sophisticated South African financial system are the rationale for applying securitisation. A proposal of how to effectively apply securitisation to low cost housing in South Africa is provided with recommendations to revive the primary market.
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