An investigation into the structure and process of forgiveness following gross human rights violations
- Authors: Adonis, Cyril Kenneth
- Date: 1999
- Subjects: Human rights , Forgiveness -- South Africa , South Africa. Truth and Reconciliation Commission , Amnesty -- South Africa , Reconciliation
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2921 , http://hdl.handle.net/10962/d1002430 , Human rights , Forgiveness -- South Africa , South Africa. Truth and Reconciliation Commission , Amnesty -- South Africa , Reconciliation
- Description: This study focuses on the structure and process of forgiveness as experienced by individuals, from the East London and surrounding areas, who either suffered gross human rights violations or who are related to someone who suffered gross human rights violations during the Apartheid era. Those who participated in the study testified at the Truth and Reconciliation Commission and expressed forgiveness towards the perpetrators of the violations. The aims of the study were to reveal: the participants' structure cif forgiveness, i.e. how they define forgiveness; the process of forgiveness, i.e. the changes that took place from the time of the violation up until the participants forgave the perpetrators: and, the relation. if any. between the participants' structure and process of forgiveness. It is argued that mainstream Psychology has neglected to study forgiveness because the subject matter is incompatible with the natural scientific method. For this reason, the study was approached from a hermeneutical paradigm. This was motivated by its ability to explicate the meaning and content of phenomena. Unstructured qualitative interviews were conducted with the participants. Data was analyzed using a multi-layered process of progressively deeper interpretation, employing a reading guide technique. Results indicated that authentic forgiveness is an unconditional commitment on the part of victims and survivors to relate positively towards the perpetrators. The relationship should include non-bitterness, non-vengeance, unconditional love and respect for their human rights. Another significant dimension of the structure of forgiveness is the fact that the desire for the truth is not abandoned although forgiveness has taken place. Forgiveness also does not take away the effects of the violation. This means that one does not forget although forgiveness has been granted. Results further indicate that the forgiveness process is highly complex, individualized and not instantaneous. The individuals have to deal with various intrapersonal conflicts and anxieties as a result of the violation, before forgiveness is explored as an option, and before they can finally forgive. Significant interrelations between the structure and process of forgiveness were also identified.
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- Date Issued: 1999
Cumulative mild head injury in rugby: cognitive test profiles of professional rugby and cricket players
- Authors: Ancer, Ruth Lauren
- Date: 1999
- Subjects: Head -- Wounds and injuries , Rugby football injuries , Cricket injuries , Cognitive therapy , Neuropsychological tests
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2925 , http://hdl.handle.net/10962/d1002434 , Head -- Wounds and injuries , Rugby football injuries , Cricket injuries , Cognitive therapy , Neuropsychological tests
- Description: This study investigates the effects of cumulative concussive and subconcussive mild head injury on the cognitive functioning of professional rugby players. A comprehensive battery of neuropsychological tests was administered to 26 professional rugby players and a noncontact sport control group of 21 professional cricket players. The test performances of the rugby players were compared to those of the cricket players. Within the rugby group, forward and backline players were compared. An analysis of mean score differences between the rugby and cricket group failed to support the presence of brain damage effects in the rugby group. However, there was significantly increased variability of scores for the rugby players compared with the cricket players on tests particularly sensitive to cognitive deficit associated with mild head injury. This invalidates the null indications of average effects, indicating that a notable proportion of rugby players’ performances were falling off relative to the rest of the rugby players on tests vulnerable to the cognitive effects of diffuse brain damage. Mean score comparisons within the rugby group indicated that it was the subgroup of forward players, in particular, whose test performances revealed deficits suggestive of cerebral damage. Specifically, deficits were found in working memory, visuoperceptual tracking, verbal memory and visual memory, a pattern of deficits commensurate with cumulative mild head injury. The theoretical perspectives of Satz’s (1997) Brain Reserve Capacity Theory and Jordan’s (1997) ‘Shuttle’ model of variability are drawn upon in order to elucidate research findings and suggestions for future research are provided.
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- Date Issued: 1999
Studies on captive rearing of spotted grunter, pommadasys commersonnii (Pisces : Haemulidae) under ambient conditions
- Authors: Bacela, Ntobeko
- Date: 1999
- Subjects: Grunts (Fishes)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5322 , http://hdl.handle.net/10962/d1005167 , Grunts (Fishes)
- Description: The effects of stocking density, size grading, feeding frequency and ambient temperature on the growth performance and size variation of spotted grunter, Pomadasys commersonnii were investigated. The time that would be required to rear the species to market size was modelled. An area where maximum growth rate could be achieved under ambient temperature conditions, and therefore the location of a commercial farm within the distribution range of spotted grunter along the coast of South Africa, was predicted. The growth performance of spotted grunter was not significantly affected by stocking density. Growth performance seemed to improve with increasing stocking density. Competitive behaviour was absent among fish in the various stocking densities. Growth in terms of fork length and body weight was not significantly different between stocking densities. The highest specific growth rate, best food consumption, food conversion ratio and protein efficiency ratio of the fish were recorded at a density of 6.4 kg/m³, whereas the best condition factor was recorded at a density of 3.8 kg/m³. The lack of significant difference in many of the growth parameters between the various stocking densities suggest that juvenile spotted grunter could be reared at densities higher than 6.4 kg/m³. Further investigations are needed to determine the optimal initial stocking density of juvenile spotted grunter under ambient temperature and photoperiod conditions. Replacing the largest fish with average sized fish did not have a significant effect on the specific growth rate and competitive behaviour based on the relationship between the coefficient of variation and average size. Feeding frequency had a sIgnificant effect on food consumption, food conversion and protein efficiency ratio, and not on size increase, specific growth rate and condition factor. Its effect on competitive behaviour could not be conclusively explained. The best food conversion ratio recorded when feeding once a day showed that although the fish consumed a limited amount of food, they utilised the food that was fed most effectively. It is suggested that the fish be fed three times a day. The survival of juvenile spotted grunter was 95.6 % when feeding three times a day compared to 90 and 90.2 % when feeding once and five times a day, respectively. Fluctuating ambient temperature had a dramatic effect on specific growth rate and food consumption of spotted grunter. Growth modelling showed that the fish could be reared to a market size of 550 g (270 mm FL) in 19 months under ambient temperature conditions (23.2°C) at Richard's Bay. The optimal predicted rearing period of 19 months is approximately seven months less than that calculated for fish in the wild, and can possibly, be reduced further by feeding a balanced diet. The overall food consumption (on a dry weight basis) in the three size classes ranged from 0.15 ± 0.16 to 0.38 ± 0.35 % body weight per day. Food conversion ratio improved with increasing fish size. This relationship was attributed to diet quality and more specifically, the protein : energy ratio. As a result, fish in the large size class had the best overall protein efficiency ratio. Maximum specific growth rates of1.5, 0.84 and 0.74 % body weight per day were recorded from the small, medium and large size classes in the peak of summer with average daily temperature ranging from 21 to 22°C. Positive slopes in the coefficient of variation against fish size in the large size class indicated the presence of competitive behaviour which was attributed to the onset of adolescence. The information from this study can be used for pilot production of spotted grunter. Further research should be undertaken to investigate captive reproduction of the species.
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- Date Issued: 1999
Printmaking at the Dakawa Art and Craft Project : the impact of ANC cultural policy and Swedish practical implementation on two printmakers trained during South Africa's transformation years
- Authors: Baillie, Giselle Katherine
- Date: 1999
- Subjects: Prints -- Technique Dakawa art and craft project Printmakers -- South Africa -- Grahamstown Prints -- Technique -- Study and teaching
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2394 , http://hdl.handle.net/10962/d1002190
- Description: In 1998, the national Department of Arts, Culture, Science and Technology published a document aimed at the growth of culture industries in South Africa (DACST, "Creative South Africa", July 1998). Focussing on aspects of economic growth which this development could generate for South Africa, it nonetheless points to issues of cultural understanding which need to be addressed. Projects aimed at the development of arts and culture in South Africa have followed troubled paths. While projects aimed at establishing discourse for this development have succeeded on many levels, the imperatives of showcasing, rather than implementing cultural concepts appropriate to South African contexts, have tended to dominate. When the Dakawa Art and Craft Project was established by the ANC, in 1992, in Grahamstown, as the locus for the deve! opment of an arts and culture discourse in the liberated South Africa, all seemed set for success. Yet, less than four years after opening, the Project was closed. While speculatory reasons for closure tended to focus on financial and administrative problems, the basis for this closure had its roots in problems of cultural understanding manifesting themselves at the Project. These reflected a lack of cultural understanding on the part of the ANC and SIDA, the Swedish administrators sent to the Project, and the lack of clear cultural guidelines on the part of the trainees to the Project itself. These reasons for the Project's failure are integral to an understanding of arts add culture development and needs in South Africa today. As other projects, aimed at the same issues of development grow, an understanding of the history of the Project's failure is essential, for it poses questions still in need of answers. Part One examines the historical significance of the Dakawa Art and Craft Project between 1982 and 1994, recording the reasons for its establishment, the path of implementation it followed, and the cultural misunderstandings it posed to development. Part Two examines the cultural context of the trainees to the Project, followed by an account of the printmaking teaching practice, and the effects of cultural concepts on two printmakers trained during the Project's initial establishment, at the time of South Africa's political transformation.
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- Date Issued: 1999
Size-fractionated phytoplankton biomass and primary production in the Southern Ocean
- Authors: Balarin, Marianne G
- Date: 1999
- Subjects: Biomass -- Analysis , Phytoplankton , Atlantic Ocean
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5765 , http://hdl.handle.net/10962/d1005453 , Biomass -- Analysis , Phytoplankton , Atlantic Ocean
- Description: The factors controlling primary production in the Southern Ocean were investigated over two years during two cruises of the South African National Antarctic Program (SANAP). The first cruise was conducted to the region of the eastern Atlantic sector of the Southern Ocean during the collaborative Scandinavian/South African Antarctic expedition conducted in austral summer (DecemberIFebruary) 1997-1998. Production studies were conducted in the vicinity of the Marginal Ice Zone (MIZ), Interfrontal Zone (IFZ) and Antarctic Polar Front(APF). The second cruise was conducted during the Third Marion Island Oceanographic Survey (MIOS III) to the region of the Sub-Antarctic Prince Edward Islands in austral autumn (April/May) 1998. Size-fractionated production rates were estimated by 14C incorporation using standard JGOFS protocols. Oceanographic data from the first cruise suggest that the three regions can be divided into two distinct regimes. Stations occupied in the vicinity of the MIZ and the APF were characterised by a shallow mixed layer depth « 40m) while at the IFZ-stations, the mixed layer depth exceeded the 1% light depth. Microphytoplankton dominated integrated chlorophyll-a biomass in the MIZ (total chlorophyll a ranged between 15.4 and 41.3 mg Chi-a. m-2) and at the APF (range between 10.7 and 31.4 mg Chi-a. m-2) , comprising > 50% of total chlorophyll-a at all these stations. Xl Within the IFZ (2 stations), nanophytoplankton dominated total integrated Chl-a biomass (range between 5.6 and 8.8 mg Chi-a. m-2) comprising, on average, 36% of the total. Picophytoplankton comprised an average of 12% of the total Chl-a biomass (range between 3.1 and 5.9 mg Chi-a. m-2) in the MIZ, 36% in the IFZ (range between 6.4 and 7.8 mg Chl-a . m-2) and 20% in the vicinity of the APF (range between 6.8 and 10.6 mg Chi-a. m-2). Total integrated primary production ranged between 316 and 729 mg C . m-2. d-1 at stations occupied in the vicinity of the MIZ, and between 292 and 317 mg C . m·2• d-l within the IFZ. At stations occupied in the region of the APF, total integrated production ranged between 708 and 926 mg C . m-2• dol. The contribution of various size fractions to total productivity generally displayed the same pattern as integrated Chl-a biomass. Microphytoplankton formed the most important contributor to total production at stations occupied in the MIZ and at the APF. Within the IFZ, nanophytoplankton dominated total daily production. Nutrient data suggest that concentrations of macro nutrients within the upper water column were above the threshold where growth would be limited. Preliminary results showed that concentrations of iron (Fe) were highest in the southern region of the MIZ and in the vicinity of the APF. During the second cruise, conducted in the vicinity of the Sub-Antarctic Front (SAF) and in the upstream, inter-island and downstream regions of the Prince Edward Islands, there was evidence of fresh water run-off from the islands, (i.e. decreased salinities and increased concentrations of ammonia and nitrate). Oceanographic data collected at the various production stations indicated that the upper water column was well mixed throughout the survey. Total integrated biomass during the study ranged between 8.5 and 20.1 mg Chi-a. m-2• No distinct patterns in total Chl-a biomass were evident. Picophytoplankton dominated total biomass comprising> 45 % of total pigment at all stations. Nanophytoplankton were the second most important contributor to total integrated biomass. Generally xu microphytoplankton contributed < 10 % of total ChI-a. Total daily integrated production was highest (442.6 mg Chi-a. m-2) at the single station occupied in the vicinity of the SAF. Outside this region, total areal production was lower, ranging from 94.5 to 353.0 mg C . m-2. d-1. With the exception of the station occupied in the vicinity of the SAF, total productivity was dominated by nanophytoplankton, which comprised between 48 and 66% of the total. Concentrations of macronutrients did not appear to be limiting to phytoplankton growth. The absence of a phytoplankton bloom in the vicinity of the islands appears to have been related to water column stability, which was influenced by the prevailing oceanographic regime during the survey. Previous studies have shown that when the SAF lies in close proximity to the islands, advecting forces prevail, resulting in the islands functioning as a flow-through system. During this study, the SAF lay immediately north of the islands. As a consequence no water was trapped in the leeward side of the islands. The results of the two cruises suggest that phytoplankton production in the four systems investigated: the Marginal Ice Zone (MIZ), Antarctic Polar Front (APF), Inter Frontal Zone (IFZ) and Prince Edward Islands (PEl), was largely controlled by water column stability. It is probable that the availability of iron, particularly in the region of the MIZ and APF, may have further contributed to the elevated production recorded in these two regions.
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- Date Issued: 1999
An investigation of a framework to evaluate computer supported collaborative work
- Authors: Beauvais, Erik Alexander Maoui
- Date: 1999
- Subjects: Computer networks , Teams in the workplace -- Data processing , Technology -- Data processing , Information technology -- Economic aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:1135 , http://hdl.handle.net/10962/d1002763 , Computer networks , Teams in the workplace -- Data processing , Technology -- Data processing , Information technology -- Economic aspects
- Description: Rapidly changing technology constantly modifies the way in which tasks are conceived and executed. Furthermore, leading organisations also encourage the use of new technology to support and establish innovative ways of doing business. For example, technology has helped to drive the globalization and tighter integration of world markets. This has facilitated, and even necessitated, business organisations to compete for work across national borders. For geographically dispersed organisations, collaboration has become critical. But this has presented time and space work complexities. Communication and collaboration technologies, for example, are needed to support such emerging co-operative business practices. The short development cycle of technology, communication and collaborative technologies included, leaves little time for testing and less for understanding the impact of new technology. To compound the problem, no established formulae exist for matching technology with work: over-investment is a waste of resources, while under-investment could lead to work failure. This research proposes a framework to assist organisations in selecting the appropriate level of technology with the work required. In this study, the methodology developed by the Evaluation Working Group, the DARPA Intelligent Collaboration and Visualization program is extended, and a matrix framework is constructed which compares the success of generic work tasks against a range of technology resources. The framework is tested using a low resource configuration, with selected work task types generally found in software development. (The Joint Application Development (JAD) methodology for software development is used as the contextual basis of the experiment.) All activities are evaluated according to selected measure components of success. A collection of research methods known as ethnography is used to examine and test the framework. Methods employed include questionnaires, interviews, interaction analysis and ethnomethodology. The results indicate that even at a low resource level, given selected criteria, collaborative technology successfully supports certain collaborative work activities. Findings also indicate that softer people issues require much more attention in order for technology to support natural collaborative work. Finally, user defined parameter testing has indicated that the framework functions as expected and designed.
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- Date Issued: 1999
The importance of personal and collective resources in coping with stressors related to industrial action at the Coldstream sawmill
- Authors: Besseling, Elizabeth Anne
- Date: 1999
- Subjects: Stress (Psychology) , Stress (Physiology) , Industrial relations -- South Africa -- Case studies , Coldstream (South africa)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2932 , http://hdl.handle.net/10962/d1002441 , Stress (Psychology) , Stress (Physiology) , Industrial relations -- South Africa -- Case studies , Coldstream (South africa)
- Description: The main purpose of the study is to investigate whether the stress response moderators served as effective variables in reducing the stress of the strike. For instance, if individuals differ in' their ability to actualise resources, does someone with a high SOC utilise friendships or supportive relationships more than someone with a low SOC? Does someone who has a high score for religious practice become less depressed when faced with a significant stressor than someone less involved in church activities?
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- Date Issued: 1999
An experimental study of the effect of Acacia mearnsii (black wattle trees) on streamflow in the Sand River, Eastern Cape
- Authors: Beyers, Gregory John
- Date: 1999
- Subjects: Wattles (Plants) -- South Africa , Wattles (Plants) -- South Africa -- Eastern Cape , Sand river (South africa) , Streamflow , Streamflow -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4832 , http://hdl.handle.net/10962/d1005507 , Wattles (Plants) -- South Africa , Wattles (Plants) -- South Africa -- Eastern Cape , Sand river (South africa) , Streamflow , Streamflow -- South Africa
- Description: This thesis explores the effect of Acacia mearnsii on streamflow in the Eastern Cape. There is a need for data on the localised effects of removing alien trees from the riparian zones within the Fynbos Biome. Fynbos catchments throughout the Western and Eastern Cape yield large quantities of good quality water which is an essential resource in the region. To convince local land owners to manage their riparian zones, small scale experimental results will prove invaluable to assure them of the immediate advantages for themselves and for downstream water users. Three permanent weirs were built 500 m apart to monitor the effect of removing A. mearnsii on streamflow in the Sand River, Eastern Cape. Consecutive weirs allowed for the comparison of streamflow between a cleared and uncleared section of the river without significant differences in riparian conditions, channel morphology and vegetation densities. A site survey confirmed comparable densities of A. mearnsii in both sections. A sample of trees was weighed and a relationship was found between diameter at breast height and above ground wet biomass. Between the first two weirs, 2.5 ha of riparian zone was cleared amounting to approximately 160tlha. Streamflow was monitored from the 10th of January 1996 to the 9th of September 1996. The average streamflow reduction for the duration of the experiment was 15.1 m³/ha/day or 551 mm per annum. Initially, after a period of above average rainfall, streamflow was augmented by discharge from the riparian zone but as conditions dried out, there was a net uptake of water with the highest average uptake of 23. 7m³/ha/day in June. A comparison between weather conditions and streamflow reduction indicated there is a complex relationship, with evidence of A. mearnsii exhibiting control of water loss during dry conditions. Acacia mearnsii trees in the riparian zone have been shown to cause significant streamflow reduction. Permanent weirs were found to be appropriate for this type of study. There is a need for further research on the effect of alien trees in riparian zones around South Africa as there is potential for significant increases in streamflow.
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- Date Issued: 1999
Development of integrated biological processing for the biodesalination of sulphate- and metal-rich wastewaters
- Authors: Boshoff, Genevieve Ann
- Date: 1999
- Subjects: Sewage -- Purification -- Biological treatment Sulfates Mineral industries -- Environmental aspects
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3899 , http://hdl.handle.net/10962/d1003958
- Description: The substantial pollution threat to the South African environment from acid mine drainage (AMD) effluents has been well documented. Due to the juvenile nature of acidity in these flows, any remediation strategies implemented will need to function effectively and at low cost for long periods of time. The widespread use of sulphate reducing biological systems for the treatment of such effluents, and in particular large volume flows, has been limited. The supply of inexpensive electron donor and carbon sources, as well as appropriate reactor designs capable of handling large volume flows, have been identified as among the principal factors limiting development of this technology. The broad aim of the research programme reported here was to undertake an evaluation of the feasibility of an algal-bacterial integrated ponding system for the treatment of AMD, and the waste stabilisation pond (WSP) as an appropriate reactor design for this application. The study attempted to demonstrate the feasibility of individual unit operations in a proposed process train using complex organic carbon serving as the electron donor source for the sulphate reducing bacteria (SRB). Studies were undertaken as laboratory and pilot-scale investigations. Tannery effluent was shown to be a functional carbon source for biological sulphate reduction, with effective removal of sulphate and organics being recorded. In turn, the use of biological sulphate reduction for the treatment of tannery effluent was demonstrated. Algal biomass was shown in laboratory studies to function as an effective carbon source for biological sulphate reduction. It is known that micro-algae produce large quantities of photosynthate which is released to the growth medium under conditions of physiological stress. The potential for the use of photosynthate production in high rate algal ponding systems and its manipulation and use as a sustainable carbon source for sulphate reduction was investigated. Growth of a mixed culture of Dunaliella under conditions of light, temperature and salinity stress demonstrated production of large quantities of organic carbon. However, growth was inhibited at high temperatures. An elevation of salinity levels led to a decrease in growth of Dunaliella, but to increased organic carbon production. Spirulina spp., on the other hand, grew well at higher temperatures but showed the highest organic carbon production, and release to the medium, under low light conditions. These results led to a proposed process for the integration of algal ponding into an integrated system for the treatment of AMD. The algal biomass may be fed into the anaerobic digester as a carbon source, or it may be passed into a High Rate Algal Pond (HRAP) where it is stressed to enhance the organic carbon content. This can then be fed into the anaerobic digester as a carbon source. The impact of high levels of sulphide in the water feeding to the algal growth compartment was investigated. Spirulina spp. isolated from a tannery waste stabilisation pond was shown to be a sulphidophilic strain of cyanobacterium, capable of being adapted to high concentrations of sulphide. Dunaliella salina on the other hand was less tolerant. These results demonstrated the practical use of algal biomass providing an oxygen-rich cap for odour control on the surface of the facultative pond as well for the secondary treatment of sulphide-rich overflow to the High Rate Algal Pond. The ability of micro-algae to elevate the pH of their surrounding environment was evaluated as a functional precipitant and neutralisation reagent for acidic metal containing wastewater. Spirulina spp. was shown to perform effectively. D. salina was less functional in this environment. Anacystis spp. was effective in elevating the pH of a defined medium as well as a zinc-rich effluent. These results indicated the practicality of a neutralising function for algal ponds in the treatment of AMD. Metal removal in the system was found to be a combined function of sulphide precipitation, removal by binding to micro-algal biomass and extracellular polymeric substances. The feasibility of waste stabilisation ponding technology use for the treatment of large volume AMD effluents was provisionally demonstrated. It was shown that complex carbon sources would be used as efficient electron donors for sulphate reduction. The integration of algal ponding into the system provides for the generation of a sustainable carbon source, odour control with the recycling of oxygen-rich water onto the top of the facultative pond, secondary treatment of the anaerobic digester overflow, and the neutralisation of the incoming acidic effluents and removal of heavy metals. Integration of the individual unit operations, the feasibility of which has been provisionally demonstrated in this study, into a continuous process train is being investigated in follow-upstudies.
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- Date Issued: 1999
Towards modelling the formation of ore bodies initial results dealing with the fluid mechanical aspects of magma chamber convection
- Authors: Botha, André Erasmus
- Date: 1999
- Subjects: Ore deposits , Fluid mechanics , Magmatism
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5492 , http://hdl.handle.net/10962/d1005278 , Ore deposits , Fluid mechanics , Magmatism
- Description: This thesis forms part of a larger effort which aims to establish the means of assessing the fluid mechanical behaviour of magma 1 as it cools inside a magma chamber surrounded by porous country rock. The reason for doing so is to advance the understanding of some types of mineral deposits; for example,the Platinum Group Elements (PGEs). The magma is modelled with the governing equations for a single-phase incompressible Newtonian fluid with variable viscosity and density. In this thesis, thermal conductivity and specific heat are approximated as constants and the country rock is treated as a conducting solid so as to save on computational time in the initial phases of the project. A basic review of the relevant literature is presented as background material and three basic models of magma chambers are discussed: crystal settling, compositional convection and double diffusive convection.The results presented in this thesis are from finite element calculations by a commercial computer code: ANSYS 5.4. This code has been employed in industry for over 26 years and has a long and successful benchmark history. In this context, finite element methods that are applicable to the code are discussed in chapter 5. In chapter 6, results that were obtained in the course of this research are presented. The thesis concludes with an indication of the possible geological significance of the results and various refinements that should be made to future models.
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- Date Issued: 1999
Physiological and non-physiological induction of gastrointestinal differentiation
- Authors: Brauns, Seth Clint Aron
- Date: 1999
- Subjects: Gastrointestinal system -- Differentiation , Gastrointestinal system -- Physiology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:11089 , http://hdl.handle.net/10948/d1015521
- Description: The human colonic carcinoma cell lines HT-29 and Caco-2 both exhibit structural and functional differentiation under appropriate culture conditions. HT-29 can be induced to differentiate by treatment with short-chain fatty acids or acetoacetate. Caco-2 cells differentiate spontaneously upon contact inhibition. In this study HT-29 cells were treated with 5 mM acetate, propionate, butyrate and acetoacetate (physiological inducers) to assess their effects on the expression of carbonic anhydrase 1, sucrase-isomaltase and alkaline phosphatase which are reported to be markers of gastrointestinal differentiation. The maturation induction observed was compared to that of the spontaneous differentiation observed in Caco-2 cells. Assays were performed over an 18 day period. Results showed a close correlation (p < 0.05) between HT-29 and Caco-2 cell on days 4 and 12. These results indicate that differentiation reported in both cell lines is comparable and can be used as a basis for further comparative studies. In addition, parallel experiments to the above were conducted using a selection of nine rationally designed cyclic dipeptides (CDPs) potential drug entities which were chosen as non-physiological inducers. The results showed that the cyclic dipeptides were able to induce the gastrointestinal phenotype as observed in HT-29 cells treated with physiological inducers. Studies on the effects of energy-related metabolism in HT-29 and Caco-2 cells as induced by physiological and non-physiological inducers indicated that energy metabolism is a significant role player in gastrointestinal differentiation. The results reported show a decrease in ATP concentrations indicating that the cyclic dipeptides, like physiological inducers, affect the energy state of the HT-29 cells and thus may effect the differentiation of these cells. A positive correlation was found between histone phsophorylation and differentiation confirming that histone phsophorylation was partly responsible for the decrease in ATP concentrations. It is suggested that the induction of differentiation in HT- 29 cells could be either due to non-specific transcription of genes by activation of a chromatin switch or specific by the activation of signal transduction pathways based on the flux of ATP through the cells. Differential display RT-PCR is probably the most sensitive method that could be used to validate the suggestion of either a nonspecific transcription of genes or a specific differentiation reported for HT-29 cells.
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- Date Issued: 1999
Evaluation of a 'defouling on demand' strategy for the ultrafiltration of brown water using activatable enzymes
- Authors: Buchanan, K
- Date: 1999
- Subjects: Water -- Purification , Ultrafiltration , Enzymes , Membranes (Technology)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3904 , http://hdl.handle.net/10962/d1003963 , Water -- Purification , Ultrafiltration , Enzymes , Membranes (Technology)
- Description: New approaches to the application of membranes for the production of potable water are constantly being sought after in anticipation of future demands for increasingly rigorous water quality standards and reduced environmental impact. A major limitation, however, is membrane fouling, which manifests itself as a continual reduction in flux over time and thus restricts the practical implementation to restore flux. Mechanical and chemical methods have been implemented to restore flux to ultrafiltration systems, but these either result in a break in the process operation or lead to membrane damage or additional pollution problems. This project was aimed to develop a 'defouling on demand' stategy for cleaning membranes used during brown water ultrafiltration. The process involves the use of activatable peroxidase enzymes, which were immobilised onto flat sheet polysulphone membranes. Following flux decline which reaches a critical level with the build-up of the foulant layer, the immobilised enzyme layer was activated by the addition of a chemical activator solution, in this case hydrogen peroxidase and manganous sulphate. Manganese peroxidase was found to be the most effective enzyme at alleviating fouling by degrading the foulant layer formed on the membrane surface and hence restored flux to the ultrafiltration system. A 93% flux improvement was observed when manganese peroxidase was activated when 800uM manganous sulphate, 100mM hydrogen peroxide were added in the presence of a manganese chelator, lactate. The concept and the potential benefits this system holds will be discussed in further detail.
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- Date Issued: 1999
Dramatic learning : a case study of theatre for development and environmental education
- Authors: Burt, Jane Caroline
- Date: 1999
- Subjects: Drama in education -- South Africa Environmental education -- Study and teaching (Elementary)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1501 , http://hdl.handle.net/10962/d1003383
- Description: The aim of my research was to introduce drama, in the form of theatre for development processes, to local Grahamstown Primary School teachers, and to work closely with one teacher to explore theatre for development in the classroom, as a means of introducing both environmental education and learner-centred, constructivist teaching methodologies. I started my research by interviewing Primary School principals as well as sending out questionnaires to teachers, to survey their understanding and practice of drama and environmental education in the school curriculum and to invite them to participate in the research project. In collaboration with Educational Drama and Theatre students, I developed two workshops to introduce theatre for development processes such as image theatre and role-play to the teachers. Nine teachers attended this workshop which was video-taped. After the workshop I gave two lessons at a local school, in partnership with a teacher. Throughout this process I kept a research journal. All action components of the research were followed up with individual interviews, group discussions and a focus group. Although the study gave rise to multiple themes, I chose to highlight two: Firstly, Curriculum 2005 advocates a move towards more learner-centred,constructivist and process-orientated pedagogies. All of the participants in this study, including myself, had intentions of adopting a new approach tq education and teaching but found that we often reverted back to earlier learnt roles of product-orientated, text-based, authoritarian approaches to education which we originally had rejected. Secondly, I reflect on how we set out viewing environmental education, education, drama and research as a process and yet all the participants, including myself, continually tried to 'put on' the perfect performance in the form of a drama, a learning experience and research. This project was a participatory research project. The textwork of the research reflects a post-structural orientation. It has been written in the form of a drama to represent the many voices of the participants, but also to question the role of research in society and make research more accessible to non-academic readers. I also intend to perform the research process at a later stage.
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- Date Issued: 1999
An investigation into the implementation of group work, as a method of social work intervention, in health settings in South Africa
- Authors: Caires, Juliet Margarita
- Date: 1999
- Subjects: Social group work , Community health services -- South Africa , Medical care -- South Africa
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:691 , http://hdl.handle.net/10962/d1006373 , Social group work , Community health services -- South Africa , Medical care -- South Africa
- Description: This research aims to discover whether social workers employed in health settings in South Africa use group work as a method of intervention with patients. It attempts to explore in which hospitals (or particular patient populations) group work is considered possible, and to discover to what extent social workers in health settings consider group work to be beneficial to patients. It also attempts to discover some of the potential difficulties experienced in initiating group work in medical settings. An effort is also made to establish, from social workers active and experienced in the field of medical social work,what place group work might have in the broader context of health services in the future. Data was obtained through the use of mailed questionnaires, which were sent to 186 health settings, across South Africa. These settings were chosen according to the following priorities: i) those known to have social workers ii) services offered (e.g. oncology, psychotherapy) iii) size of the setting iv) geographical location (both urban and rural in all nine provinces). The sample included general public and private hospitals, psychiatric hospitals (both public and private), mining hospitals and other health settings such as old age homes and facilities for the mentally retarded and for alcohol and drug rehabilitation (accompanied by a medical facility). Responses were received from 90 health settings, with 64 of these being completed questionnaires. The majority of responses came from public hospitals, and the least from the mining hospital category. Findings of this study indicate that group work is used by 50% of the health settings in South Africa. Groups are most often therapeutic or educational in nature, are run on average once a week for an hour, and are usually of open membership. Group work is not used in some health settings, most commonly due to insufficient time (on the part of the social worker). From the findings, it seems that many more social workers would like to run groups for patients than they do presently. The benefits of group work are acknowledged by the majority of this study's sample of social workers, and if solutions could be found to problems such as heavy caseloads and insufficient time, more social workers would choose to use group work than are doing so currently. Group work is considered to be a feasible method, both in the hospitals and at primary health care level. With South Africa's growing emphasis on primary health care, and the proposed inclusion (by the Department of Health) of social work services at this level, it is important that social workers find a way in which to meet the needs of patients at both levels. With group work, this may be possible.
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- Date Issued: 1999
An economic analysis of eradicating alien vegetation as an alternative to conventional water supply schemes: a case study of the Krom and Kouga
- Authors: Carpenter, Robert Charles
- Date: 1999
- Subjects: Alien plants -- South Africa , Water-supply -- South Africa , Kouga River (South Africa)
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1000 , http://hdl.handle.net/10962/d1002735 , Alien plants -- South Africa , Water-supply -- South Africa , Kouga River (South Africa)
- Description: South Africa is classified as an arid to semi-arid region and water scarcity in South Africa has been identified as a key factor limiting socioeconomic development in the next century. In the Algoa region, the total urban plus agricultural water demand is expected to exceed the supply by the year 2005. The Kouga Working for Water Project aims to increase the base flow to the existing dams which supply the Port Elizabeth metropolitan area through the eradication of invasive alien trees in the riparian areas of the Krom and Kouga catchments. This thesis analyses the economic efficiency of optimal catchment management as a water supply scheme. A cost-benefit analysis is conducted for the Kouga eradication programme, and its desirability is evaluated in terms of the net present value (NPV) and the internal rate of return (IRR) criteria. In order to compare the cost-e~i.ciency of the eradication programme to alternative water supply augmentation schemes the Unit Reference Value (URV) is calculated for the project. The NPV for the project is calculated using a discount rate of 7% and amounts to nearly R24 million. This positive NPV indicates that the project is economically desirable in that it results in the improvement of human welfare. The IRR decision rule supports this finding. The URV of the eradication scheme is found to be competitive to that generated by more conventional schemes. Considered in the evaluation of the project are a host of environmental benefits that accompany the eradication of alien vegetation. This is in contrast to alternative schemes which result in several detrimental impacts to the environment. The economic analysis concludes that the eradication of alien vegetation is an efficient and desirable alternative water supply augmentation scheme. The conclusions drawn from the analysis of the eradication programme in this catchment area can be extended to other catchment areas, with the aim of promoting the most efficient supply of water.
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- Date Issued: 1999
A comparison of the views of South African and American photojournalists to the digital manipulation of news photographs
- Authors: Cass, Taryn May
- Date: 1999
- Subjects: Photojournalists , Photojournalism , Digital media -- Management , Photography -- Digital techniques , Digital media , Photojournalism -- Moral and ethical aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3420 , http://hdl.handle.net/10962/d1002873 , Photojournalists , Photojournalism , Digital media -- Management , Photography -- Digital techniques , Digital media , Photojournalism -- Moral and ethical aspects
- Description: Digital technology has now become pervasive at most publications in South Africa and in America. Pictures are routinely digitised by publications for ease of handling in the layout process, and this makes it relatively easy to alter or manipulate the pictures using computer software programmes. This thesis attempts to gauge the views of South African photojournalists about the digital manipulation of news photographs, and compare these to the views of American photojournalists. It is based on the hypothesis that South African and American photojournalists have different views of what is acceptable manipulation of news photographs, and that their reasons for this will also be different. This thesis also suggests that the manipulation of news photographs is ethically problematic and can damage the credibility of both the photojournalist and the publication in which the photographs appear. The study involves a comparison of the results from a questionnaire given to South African photojournalists and a similar questionnaire given to American photojournalists. The questionnaires were then supplemented by interviews with six South African photojournalists. The thesis then draws conclusions from the responses to the questionnaires and interviews. These conclusions partially support the initial hypothesis, in that there are some differences between the views of South African and American photojournalists, but, on the whole, these are remarkably similar. Photojournalists do seem to find the manipulation of news photographs to be ethically problematic, but they may find the manipulation of other kinds of images (eg fashion or soft news) to be acceptable. South African photographers also find the manipulation of images by other means (eg different lenses or darkroom techniques) to be more acceptable than Americans do. Although the underlying reasons for these views may differ, maintaining the credibility of the photographer and the publication does seem to be the major issue for avoiding digital manipulation. South African photographers seemed to think that if the photographer had done his or her job well, there would be no need for manipulation, and both groups (but especially the Americans) felt that manipulation could often be equated to lying to the reader, and that this might damage their reputation, and that of their publications.
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- Date Issued: 1999
Insubordination in the workplace
- Authors: Chadd, Kevin Mark
- Date: 1999
- Subjects: Employees -- Dismissal of -- Law and legislation -- South Africa , Labor laws and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3668 , http://hdl.handle.net/10962/d1003183 , Employees -- Dismissal of -- Law and legislation -- South Africa , Labor laws and legislation -- South Africa
- Description: This thesis traces the development of insubordination in the employment relationship. The essence of the relationship is that the employee, by contracting out his or her productive capacity, occupies a subordinate position. The primary aim is to locate and define the nature of subordination and to investigate how the breach of this position would justify dismissal as interpreted and applied by the courts. This is achieved by investigating dismissal for insubordination under the common law contract of employment, the unfair labour practice jurisdiction and the 1995 Labour Relations Act. Initially the obligation of the employee to be subordinate, an essential term of the contract of employment, is located and defined by using the tests of Control, Organisation and Dominant Impression, which theoretically indicate the true nature of insubordination. Insubordination under the common law is equated with disobedience to the lawful and reasonable instructions of the employer which were given in good faith and fell squarely within the contractual relationship. Insubordination under the unfair labour practice jurisdiction was equated with a challenge to the authority of the employer of which disobedience was a manifestation of such intention. Instructions given by the employer under the unfair labour practice jurisdiction had to be lawful, reasonable and fair. What was fair depended on the surrounding circumstances of the dismissal and a wilful and unreasonable refusal of the employee to obey the valid instructions of the employer justified dismissal Under the 1995 Labour Relations Act it is submitted that insubordination will be dealt with in essentially the same manner as under the previous jurisdiction, subject to the Act's objectives and purposes. The disobedience of the employee is to be tolerated if that employee is attempting to achieve the Act's objectives, and any dismissal as a result of the disobedience could be unfair, because the employer's conduct fiustrates the purpose of the Act. Therefore, the contractual right of the employer to expect subordination from the employee may have been whittled away to such an extent over time that it seems superficial to regard subordination as an essential term of the contract of employment.
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- Date Issued: 1999
An investigation into the effect of military influences on the theology and form of The Spiritual Exercise of Ignatius of Loyola
- Authors: Christie, David Osborne
- Date: 1999
- Subjects: Ignatius, of Loyola, Saint, 1491-1556. Exercitia spiritualia
- Language: English
- Type: Thesis , Masters , MTh
- Identifier: vital:1241 , http://hdl.handle.net/10962/d1008540
- Description: The purpose of this thesis is to investigate the influences of a military nature affecting the life of Ignatius of Loyola up to the time he wrote The Spiritual Exercises, and to assess whether such influences may have affected the theology and form of The Spiritual Exercises. The investigation opens with an apologetic on why the author considers it desirable to examine The Spiritual Exercises from this point of view. Thereafter a review of the life of Ignatius up to the time he wrote The Exercises is undertaken to identify which sources may have provided influences of a military nature or nuance, and to examine what possible effect these had upon Ignatius. The potential sources of influence examined include Ignatius's family background and the milieu in which he grew up, the attitude of his mentors in particular and society in general to the profession of arms, and Ignatius's own response to this attitude. From the age of twenty-five to thirty Ignatius was employed on duties of a principally military nature until he was severely wounded at the Battle of Pamplona in 1521. Therefore his military experience is examined together with an attempt to assess the degree, if any, of his spirituality at that point in his life. This is followed by an investigation of the literary sources available to Ignatius from the time of his wounding up to the time when he wrote The Spiritual Exercises at Manresa. Thereafter an examination of the changes which took place in his psyche and spirit, from the time he was wounded up to the time he wrote The Spiritual Exercises is undertaken, in order to ascertain whether his attitude to military concepts immediately prior to writing The Exercises had changed from his pre-Pamplona days. The Spiritual Exercises are then examined to consider which portions, if any, were affected in form or theology by military influences or nuances. The conclusion reached is that whereas The Spiritual Exercises are in no way a military treatise, the form is affected to a reasonable degree by Ignatius's experiences of, and attitude to, the military life, whereas the theology is affected only slightly.
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- Date Issued: 1999
The psychological adjustment of middle managers after revolutionary organisational change
- Authors: Coates, Nicholas Robert
- Date: 1999
- Subjects: Psychology, Industrial -- South Africa Organizational change -- South Africa Organizational change -- Psychological aspects Management -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3190 , http://hdl.handle.net/10962/d1008554
- Description:
With the accelerated process of political and socio-economic transformation in South Africa, revolutionary organisational change has become a given in contemporary South African business life (Human & Horwitz, 1992). For revolutionary organisational change to succeed in South Africa, middle managers who represent the 'cement' of the organisation, need to adjust at the individual level. However, the literature on organisational change remains curiously silent about individual adjustment (Ashford, 1988). The goals of the research were firstly, to recount the middle manager's perceptions and experiences of revolutionary organisational change. Secondly, to detail the psychological re-
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- Date Issued: 1999
Fish population dynamics in a temporarily open/closed South African estuary
- Authors: Cowley, Paul D (Paul Denfer), 1964-
- Date: 1999
- Subjects: Fish populations Estuarine ecology -- South Africa -- Eastern Cape Estuarine fishes -- Ecology -- South Africa Fish populations -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5354 , http://hdl.handle.net/10962/d1008543
- Description: The primary aim of this study was to investigate the population dynamics of the fishes associated with a small (17.5 hectares) temporarily open/closed estuary on the south east coast of South Africa. The results are based on the findings of an intensive sampling programme conducted over a period of four years in the East Kleinemonde estuary (33° 32' S : 27° 03' E). By adopting a quantitative approach, this study addresses the need for information on estuarine-associated fish population sizes, standing stock (biomass) estimates and productivity. The ichthyoplankton assemblage in the surf zone adjacent to the mouth of the estuary was dominated by postflexion larvae representing at least 21 taxa in 14 families. Rhabdosargus holubi of sizes ranging between 9 mm and 21 mm BL was the most abundant species with a mean density of 7.3 individuals per 100 m'. This species, which accounted for 77.6% of the catch composition, was recorded throughout the year but revealed a distinct peak in abundance in spring (August - September). The ichthyofaunal community within the East Kleinemonde estuary was dominated by juvenile marine-spawning species and typical of a warm temperate southern African estuary. A total of 30 species in 17 families was recorded, including the endangered estuarine pipefish Syngnathus watermeyeri. Multivariate analyses (classification and ordination) of the catch assemblages revealed a high degree of similarity (> 70%) throughout the estuary, with two distinct groups being identified on the basis of substratum type. The sampling stations near the mouth with a sandy substratum were distinguished from all other sampling sites in the estuary. The dominant estuarine-spawning species were represented by all life-history stages, suggesting that they bred successfully in the estuary. This group was numerically and gravimetrically dominated by the two zooplanktivorous shoaling species Gilchristella aestuaria and Atherina breviceps with density extrapolated population size estimates of 420 973 and 198 275 individuals, and biomass estimates of 1.6 and 0.6 g m⁻² respectively. The total population size of all estuarine-spawning species with a mean biomass 00.4 g m⁻² was estimated at 754 217 individuals. Population size estimates of the marine-spawning species were calculated using data obtained from three independent mark-recapture experiments. The assumptions for the mark-recapture analyses were adequately met and it was concluded that the techniques provided reliable estimates of population size. However, estimates obtained from density extrapolation revealed enormous variability and were considered to be unreliable. The total population size was estimated at 63 342, 18 592 and 13 5 192 during the three mark-recapture experiments respectively. The numerically dominant species during all three experiments was Rhabdosargus holubi. Biomass production of the marine-spawning species was evaluated over a 123 day census period when population sizes and estimates of growth rates were known. Productivity for all fishes with a standing stock of 26.2 g m⁻² was calculated at 4.5 g m⁻² month01 Rhabdosargus holubi accounted for more than 75% of the total marine fish productivity. This study draws attention to the success of Rhabdosargus holubi in the East Kleinemonde estuary, which is ascribed to aspects of its biology. These include an extended breeding season, the ability to recruit into the estuary under adverse open mouth conditions and its omnivorous food habits. The dominance of this migratory species suggests that it plays an important role in the transfer of energy to the coastal marine environment when the mouth of the East Kleinemonde estuary opens. Predation by birds and a dominant piscivorous fish (Lichia amia) was quantitatively assessed over a period of two years. Monthly food consumption by all piscivorous birds revealed large temporal variability, ranging from 32 to 466 kg month-I An unusual invasion of Cape cormorants during the winter of 1994 accounted for large scale mortality (2246 kg of fish) over a relatively short period. The predatory impact of this episodic event was reflected in the findings of the fish mark-recapture experiments, which revealed a 70% reduction in the total population of marine-spawning fishes (above a certain minimum size) in the estuary subsequent to this invasion. Monthly food consumption by the Lichia amia population in the estuary was calculated at 68 and 58 kg month-I for two distinct time periods when the population size was known. These findings suggest that this species is the top piscivorous predator in the East Kleinemonde estuary. Finally, the findings of this study highlight the temporal variability of fish populations within a single estuary. It is suggested that predation and estuary mouth conditions are the main factors influencing the abundance (and its variability) of individual species in the East Kleinemonde estuary.
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- Date Issued: 1999