Normative indicators for a black, Xhosa speaking population without tertiary education on four tests used to access malingering
- Authors: Wong, Andrea Jane
- Date: 2009
- Subjects: Malingering Neuropsychological tests Language and languages -- Ability testing Educational tests and measurements Education evaluation Xhosa (African people) -- Education
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3088 , http://hdl.handle.net/10962/d1002597
- Description: Malingering has become an increasing concern in neuropsychological assessment in recent years, and a wide range of tests have been designed and examined for the purpose of detecting malingering. Cut-off scores have been recommended for these tests in order to provide indications of malingering performances. However, the derived scores have been in respect of westernised populations of people with relatively high levels of education who speak English as their first language. Accordingly, the current study aimed to attain normative data and cut-off scores for four commonly employed neuropsychological tools, administered in English, on a population of black, South African, Xhosa-speaking people (N = 33), who attended a former DET-type school in the Eastern Cape, with a Grade 11-12 level of education, in the age range of 18 - 40 years. The targeted measures included the TOMM, the Rey-15 Item Memory Test, the Digit Span subtest of the WAIS-III, and the Trail Making Test. The obtained scores were poorer than the previously published cut-offs for at least one component of each of the tests investigated, except the TOMM. The fmdings of this study highlight the important role that the factors of culture, quality of education, and language play in neuropsychological test performance.
- Full Text:
- Authors: Wong, Andrea Jane
- Date: 2009
- Subjects: Malingering Neuropsychological tests Language and languages -- Ability testing Educational tests and measurements Education evaluation Xhosa (African people) -- Education
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3088 , http://hdl.handle.net/10962/d1002597
- Description: Malingering has become an increasing concern in neuropsychological assessment in recent years, and a wide range of tests have been designed and examined for the purpose of detecting malingering. Cut-off scores have been recommended for these tests in order to provide indications of malingering performances. However, the derived scores have been in respect of westernised populations of people with relatively high levels of education who speak English as their first language. Accordingly, the current study aimed to attain normative data and cut-off scores for four commonly employed neuropsychological tools, administered in English, on a population of black, South African, Xhosa-speaking people (N = 33), who attended a former DET-type school in the Eastern Cape, with a Grade 11-12 level of education, in the age range of 18 - 40 years. The targeted measures included the TOMM, the Rey-15 Item Memory Test, the Digit Span subtest of the WAIS-III, and the Trail Making Test. The obtained scores were poorer than the previously published cut-offs for at least one component of each of the tests investigated, except the TOMM. The fmdings of this study highlight the important role that the factors of culture, quality of education, and language play in neuropsychological test performance.
- Full Text:
Organizational culture and innovation: the case of the Namibian National Institute for Educational Development
- Piepmeyer, Gernot Maximilian
- Authors: Piepmeyer, Gernot Maximilian
- Date: 2009
- Subjects: National Institute for Educational Development (Namibia) Corporate culture -- Namibia Organizational behavior -- Namibia Technological innovations -- Namibia Education -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1685 , http://hdl.handle.net/10962/d1003568
- Description: The purpose of my research is to diagnose the organizational culture of the National Institute for Educational Development [NIED] , in particular to determine whether it is conducive to innovation, as was envisaged at the time of its inception. The diagnosis of NIED's organizational culture was done by using a hybrid qualitative and quantitative case study. A questionnaire, the Cameron and Quinn's Organizational Culture Assessment Instrument [OCAI], was given to all professional members at NIED, while six members of the NIED organization were interviewed. It emerged from the data, first, that the characteristics of the dominant NIED culture, using Cameron and Quinn's six dimensions of culture that produced an "overall culture profile" of NIED, are not likely to enhance innovativeness. Nevertheless, there is a strong preference towards a culture type favourable to innovation. Second, there are cultural factors antithetical to an innovative organizational culture. These include poor information flow and a lack of communication, negligible crossfunction interaction and freedom, and constraining hierarchical and bureaucratic structures. Third, NIED has, in the form of a "green paper," a set of critical norms, values and assumptions that characterize the culture of innovative organizations. Finally, there is evidence of the presence of cultural characteristics conducive to an innovative organizational culture. These include: learning how to learn; being pro-active in initiating change and innovativeness; and sustaining momentum, consistency and perseverance. The discrepancy between the existing organizational culture and the preferred organizational culture revealed by the overall cultural profile can be explained by the fact that the norms, values and assumptions that characterize the culture of innovative organizations and the cultural characteristics conducive to an innovative organizational culture are not fully infused into the whole organization. There is a tension between NIED's bureaucratic nature and its innovative mission. Organizational culture change, where NIED's structures and processes are aligned with its espoused vision and mission, is needed in order for it to be better placed to achieve its original pioneering mandate.
- Full Text:
- Authors: Piepmeyer, Gernot Maximilian
- Date: 2009
- Subjects: National Institute for Educational Development (Namibia) Corporate culture -- Namibia Organizational behavior -- Namibia Technological innovations -- Namibia Education -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1685 , http://hdl.handle.net/10962/d1003568
- Description: The purpose of my research is to diagnose the organizational culture of the National Institute for Educational Development [NIED] , in particular to determine whether it is conducive to innovation, as was envisaged at the time of its inception. The diagnosis of NIED's organizational culture was done by using a hybrid qualitative and quantitative case study. A questionnaire, the Cameron and Quinn's Organizational Culture Assessment Instrument [OCAI], was given to all professional members at NIED, while six members of the NIED organization were interviewed. It emerged from the data, first, that the characteristics of the dominant NIED culture, using Cameron and Quinn's six dimensions of culture that produced an "overall culture profile" of NIED, are not likely to enhance innovativeness. Nevertheless, there is a strong preference towards a culture type favourable to innovation. Second, there are cultural factors antithetical to an innovative organizational culture. These include poor information flow and a lack of communication, negligible crossfunction interaction and freedom, and constraining hierarchical and bureaucratic structures. Third, NIED has, in the form of a "green paper," a set of critical norms, values and assumptions that characterize the culture of innovative organizations. Finally, there is evidence of the presence of cultural characteristics conducive to an innovative organizational culture. These include: learning how to learn; being pro-active in initiating change and innovativeness; and sustaining momentum, consistency and perseverance. The discrepancy between the existing organizational culture and the preferred organizational culture revealed by the overall cultural profile can be explained by the fact that the norms, values and assumptions that characterize the culture of innovative organizations and the cultural characteristics conducive to an innovative organizational culture are not fully infused into the whole organization. There is a tension between NIED's bureaucratic nature and its innovative mission. Organizational culture change, where NIED's structures and processes are aligned with its espoused vision and mission, is needed in order for it to be better placed to achieve its original pioneering mandate.
- Full Text:
Phenolic compounds in water and the implications for rapid detection of indicator micro-organisms using ß-D-Galactosidase and ß-D-Glucuronidase
- Authors: Abboo, Sagaran
- Date: 2009
- Subjects: Water -- Purification -- Biological treatment , Pollutants -- Biodegradation , Phenol , Organic water pollutants , Water quality biological assessment , Water -- Pollution
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3978 , http://hdl.handle.net/10962/d1004037 , Water -- Purification -- Biological treatment , Pollutants -- Biodegradation , Phenol , Organic water pollutants , Water quality biological assessment , Water -- Pollution
- Description: Faecal contamination in water is detected using appropriate microbial models such as total coliforms, faecal coliforms and E. coli. Βeta-D-Galactosidase (β-GAL) and Beta-D-glucuronidase (β-GUD) are two marker enzymes that are used to test for the presence of total coliforms and E. coli in water samples, respectively. Various assay methods have been developed using chromogenic and fluorogenic substrates. In this study, the chromogenic substrates chlorophenol red β-D-galactopyranoside (CPRG) for β-GAL and p-nitrophenyl-β-D-galactopyranoside (PNPG) for β-GUD were used. Potential problems associated with this approach include interference from other organisms present in the environment (e.g. plants, algae and other bacteria), as well as the presence of certain chemicals, such as phenolic compounds in water. Phenolic compounds are present in the aquatic environment due to their extensive industrial applications. The USA Enviromental Protection Agency (EPA) lists 11 Priority Pollutant Phenols (PPP) due to their high level of toxicity. This study investigated the interfering effects of the eleven PPP found in water on the enzyme activities of both the β-GAL and β-GUD enzyme assays. The presence of these PPP in the β-GAL and β-GUD enzyme assays showed that over and underestimation of activity may occur due to inhibition or activation of these enzymes. Three types of inhibition to enzyme activities were identified from double reciprocal Lineweaver-Burk plots. The inhibition constants (Ki) were determined for all inhibitory phenolic compounds from appropriate secondary plots. Furthermore, this study presented a validated reverse phase high performance liquid chromatography (RP-HPLC) method, developed for the simultaneous detection, separation and determination of all eleven phenolic compounds found in the environment. This method demonstrated good linearity, reproducibility, accuracy and sensitivity. Environmental water samples were collected from rivers, streams, industrial sites and wastewater treatment plant effluent. These samples were extracted and concentrated using a solid phase extraction (SPE) procedure prior to analysis employing the newly developed HPLC method in this study. Seasonal variations on the presence of the PPP in the environment were observed at certain collection sites. The concentrations found were between 0.033 μg/ml for 2,4-dinitrophenol in a running stream to 0.890 mg/ml for pentachlorophenol from an tannery industrial site. These concentrations of phenolic compounds found in these environments were able to interfere with the β-GAL and β-GUD enzyme assays.
- Full Text:
- Authors: Abboo, Sagaran
- Date: 2009
- Subjects: Water -- Purification -- Biological treatment , Pollutants -- Biodegradation , Phenol , Organic water pollutants , Water quality biological assessment , Water -- Pollution
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3978 , http://hdl.handle.net/10962/d1004037 , Water -- Purification -- Biological treatment , Pollutants -- Biodegradation , Phenol , Organic water pollutants , Water quality biological assessment , Water -- Pollution
- Description: Faecal contamination in water is detected using appropriate microbial models such as total coliforms, faecal coliforms and E. coli. Βeta-D-Galactosidase (β-GAL) and Beta-D-glucuronidase (β-GUD) are two marker enzymes that are used to test for the presence of total coliforms and E. coli in water samples, respectively. Various assay methods have been developed using chromogenic and fluorogenic substrates. In this study, the chromogenic substrates chlorophenol red β-D-galactopyranoside (CPRG) for β-GAL and p-nitrophenyl-β-D-galactopyranoside (PNPG) for β-GUD were used. Potential problems associated with this approach include interference from other organisms present in the environment (e.g. plants, algae and other bacteria), as well as the presence of certain chemicals, such as phenolic compounds in water. Phenolic compounds are present in the aquatic environment due to their extensive industrial applications. The USA Enviromental Protection Agency (EPA) lists 11 Priority Pollutant Phenols (PPP) due to their high level of toxicity. This study investigated the interfering effects of the eleven PPP found in water on the enzyme activities of both the β-GAL and β-GUD enzyme assays. The presence of these PPP in the β-GAL and β-GUD enzyme assays showed that over and underestimation of activity may occur due to inhibition or activation of these enzymes. Three types of inhibition to enzyme activities were identified from double reciprocal Lineweaver-Burk plots. The inhibition constants (Ki) were determined for all inhibitory phenolic compounds from appropriate secondary plots. Furthermore, this study presented a validated reverse phase high performance liquid chromatography (RP-HPLC) method, developed for the simultaneous detection, separation and determination of all eleven phenolic compounds found in the environment. This method demonstrated good linearity, reproducibility, accuracy and sensitivity. Environmental water samples were collected from rivers, streams, industrial sites and wastewater treatment plant effluent. These samples were extracted and concentrated using a solid phase extraction (SPE) procedure prior to analysis employing the newly developed HPLC method in this study. Seasonal variations on the presence of the PPP in the environment were observed at certain collection sites. The concentrations found were between 0.033 μg/ml for 2,4-dinitrophenol in a running stream to 0.890 mg/ml for pentachlorophenol from an tannery industrial site. These concentrations of phenolic compounds found in these environments were able to interfere with the β-GAL and β-GUD enzyme assays.
- Full Text:
Photophysical and photochemical behaviour of metallophthalocyanines effect of nanoparticles and molecules of biological importance
- Authors: Idowu, Mopelola Abidemi
- Date: 2009
- Subjects: Electrochemistry Phthalocyanines Nanoparticles
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4329 , http://hdl.handle.net/10962/d1004990
- Description: Syntheses, spectral, photophysical and photochemical studies of some neutral, anionic and cationic metallophthalocyanine derivatives are presented. The effects of central metal ions, solvents, aggregation, surfactant, nanoparticles and bovine serum albumin on the photophysical and photochemical behaviour are investigated. Mercaptocarboxylic acid stabilized CdTe quantum dots (QDs) were used as energy donors to anionic water-soluble MPcs through Förster resonance energy transfer (FRET). Energy transfer (ET) from the QDs to the MPcs occurred upon photoexcitation of the QDs. An enhancement in efficiency of ET with the nature of the cappings on the QDs was observed with few occurrences of a non-Förster type ET. QDs were found to improve the photophysicochemical behaviour of the MPcs, with the possibility of indirect production of singlet oxygen (Φ[subscript Δ]) via FRET mechanism. Interaction of the QDs with cationic water-souble MPcs produced ion-pair complexes resulting in aggregates due to strong electronic coupling. The stoichiometry of the reaction and association constants are evaluated by the continuous variation method. Improved photophysicochemical behaviour with no spectral alterations was observed in MPcs in the presence of magnetic fluid. Complexes showed high triplet quantum yields with corresponding long lifetimes and high photostability. Elucidation of the results of the interaction of bovine serum albumin (BSA) with MPcs or QDs is presented. Increased efficiency of Φ[subscript Δ] generation of MPcs in the presence of BSA coupled with large binding constants, suggesting strong interaction of the MPcs with BSA was observed. Enhanced emission intensity of QDs when linked to or in a mixture with BSA due to radiationless recombination at the surface vacancies was also observed. The study revealed positive deviation from Stern-Volmer relationship suggesting the occurrence of static and dynamic mechanisms of quenching together. Fluorescence quenching of the MPcs by benzoquinone, analysed by Stern-Volmer relationship is also presented; the results were employed in determining fluorescence lifetimes of the complexes. Photoelectrochemical characteristics of MPc-sensitized electrodeposited ZnO thin films were studied; ZnOCPc / ZnO films have been improved to an incident photon-to-currentconversion (IPCE) value of 31.1 % with an absorbed photon-to-current conversion (APCE) of 59.6 %. The best obtained so far with phthalocyanine-type sensitizers on nanocrystalline ZnO films. Fluorescent-magnetic nanocomposite with excellent photophysical properties which can be exploited for combined photodynamic and hyperthermia therapies is also presented.
- Full Text:
- Authors: Idowu, Mopelola Abidemi
- Date: 2009
- Subjects: Electrochemistry Phthalocyanines Nanoparticles
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4329 , http://hdl.handle.net/10962/d1004990
- Description: Syntheses, spectral, photophysical and photochemical studies of some neutral, anionic and cationic metallophthalocyanine derivatives are presented. The effects of central metal ions, solvents, aggregation, surfactant, nanoparticles and bovine serum albumin on the photophysical and photochemical behaviour are investigated. Mercaptocarboxylic acid stabilized CdTe quantum dots (QDs) were used as energy donors to anionic water-soluble MPcs through Förster resonance energy transfer (FRET). Energy transfer (ET) from the QDs to the MPcs occurred upon photoexcitation of the QDs. An enhancement in efficiency of ET with the nature of the cappings on the QDs was observed with few occurrences of a non-Förster type ET. QDs were found to improve the photophysicochemical behaviour of the MPcs, with the possibility of indirect production of singlet oxygen (Φ[subscript Δ]) via FRET mechanism. Interaction of the QDs with cationic water-souble MPcs produced ion-pair complexes resulting in aggregates due to strong electronic coupling. The stoichiometry of the reaction and association constants are evaluated by the continuous variation method. Improved photophysicochemical behaviour with no spectral alterations was observed in MPcs in the presence of magnetic fluid. Complexes showed high triplet quantum yields with corresponding long lifetimes and high photostability. Elucidation of the results of the interaction of bovine serum albumin (BSA) with MPcs or QDs is presented. Increased efficiency of Φ[subscript Δ] generation of MPcs in the presence of BSA coupled with large binding constants, suggesting strong interaction of the MPcs with BSA was observed. Enhanced emission intensity of QDs when linked to or in a mixture with BSA due to radiationless recombination at the surface vacancies was also observed. The study revealed positive deviation from Stern-Volmer relationship suggesting the occurrence of static and dynamic mechanisms of quenching together. Fluorescence quenching of the MPcs by benzoquinone, analysed by Stern-Volmer relationship is also presented; the results were employed in determining fluorescence lifetimes of the complexes. Photoelectrochemical characteristics of MPc-sensitized electrodeposited ZnO thin films were studied; ZnOCPc / ZnO films have been improved to an incident photon-to-currentconversion (IPCE) value of 31.1 % with an absorbed photon-to-current conversion (APCE) of 59.6 %. The best obtained so far with phthalocyanine-type sensitizers on nanocrystalline ZnO films. Fluorescent-magnetic nanocomposite with excellent photophysical properties which can be exploited for combined photodynamic and hyperthermia therapies is also presented.
- Full Text:
Photosynthetic and evolutionary determinants of the response of selected C3 and C4 (NADP-ME) grasses to fire
- Authors: Martin, Tarryn
- Date: 2009
- Subjects: Photosynthesis , Carbon -- Metabolism , Grasses -- Adaptation , Plants -- Effect of fires on , Grasses -- Research , Grasses -- Physiology , Grasses -- Evolution , Grasslands -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4211 , http://hdl.handle.net/10962/d1003780 , Photosynthesis , Carbon -- Metabolism , Grasses -- Adaptation , Plants -- Effect of fires on , Grasses -- Research , Grasses -- Physiology , Grasses -- Evolution , Grasslands -- Research
- Description: Species possess characteristics that are considered adapted to burning and these allow them to outcompete species and dominate in fire prone environments. It has therefore been proposed that fire might have played a critical role in the observed expansion of the grasslands, during the late Miocene. The aim of this study was (i) to investigate whether plant response to fire was a result of physiology or (ii) whether it was due to phylogenetic history. This was achieved by doing a pair-wise comparison between Panicoideae (and Panicoideae) and non-Panicoideae (Danthonioideae and Aristidoideae) species. Pre-fire characteristics, that would enhance fire frequency and assist with plant recovery after burning, were compared across phylogenies and photosynthetic type. Post fire plant recovery was then followed in a field and pot comparison which examined the re-growth of the leaf canopy area, leaf mass, above-ground biomass and the cost of this to the below-ground biomass. The pre-fire characteristics showed both a photosynthetic and phylogenetic response. It was found that the species showed a greater canopy death during winter and had a lower moisture content than the species. These characteristics would potentially contribute towards a larger fuel load in the species. However, the comparison of the dead standing biomass at the end of winter and the below-ground biomass, showed a phylogenetic response with the Panicoideae having a proportionally larger dead standing biomass and below-ground biomass than the non-Panicoideae. These results suggest that not only did the Panicoideae have a larger potential fuel load but that they also shunted carbon below-ground, enabling a fast recovery after being burned. The post-fire results were more strongly determined by phylogeny than by photosynthetic type. The Panicoideae recovered faster and more completely than the non-Panicoideae grasses, possibly contributing to their success and expansion under conditions of increased fire frequency. Although recovery of the and Panicoideae were similar, frequently burnt grasslands are dominated by the Panicoideae. Hence, this dominance cannot be explained by differences in their fire responses and may be determined by the post-fire environmental conditions that potentially advantage species possessing the photosynthetic pathway. Panicoideae dominance is limited to mesic environments where fire is the likely driver of grassland expansion while more arid environments are dominated by non-Panicoideae species. Representative species from these non-Panicoid subfamilies showed poor recovery after fire. This suggests that factors other than fire were the likely drivers of these xeric grassland expansions. The ability of these subfamilies, and particularly the species, to cope with drought remains a likely selective mechanism that requires further research.
- Full Text:
- Authors: Martin, Tarryn
- Date: 2009
- Subjects: Photosynthesis , Carbon -- Metabolism , Grasses -- Adaptation , Plants -- Effect of fires on , Grasses -- Research , Grasses -- Physiology , Grasses -- Evolution , Grasslands -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4211 , http://hdl.handle.net/10962/d1003780 , Photosynthesis , Carbon -- Metabolism , Grasses -- Adaptation , Plants -- Effect of fires on , Grasses -- Research , Grasses -- Physiology , Grasses -- Evolution , Grasslands -- Research
- Description: Species possess characteristics that are considered adapted to burning and these allow them to outcompete species and dominate in fire prone environments. It has therefore been proposed that fire might have played a critical role in the observed expansion of the grasslands, during the late Miocene. The aim of this study was (i) to investigate whether plant response to fire was a result of physiology or (ii) whether it was due to phylogenetic history. This was achieved by doing a pair-wise comparison between Panicoideae (and Panicoideae) and non-Panicoideae (Danthonioideae and Aristidoideae) species. Pre-fire characteristics, that would enhance fire frequency and assist with plant recovery after burning, were compared across phylogenies and photosynthetic type. Post fire plant recovery was then followed in a field and pot comparison which examined the re-growth of the leaf canopy area, leaf mass, above-ground biomass and the cost of this to the below-ground biomass. The pre-fire characteristics showed both a photosynthetic and phylogenetic response. It was found that the species showed a greater canopy death during winter and had a lower moisture content than the species. These characteristics would potentially contribute towards a larger fuel load in the species. However, the comparison of the dead standing biomass at the end of winter and the below-ground biomass, showed a phylogenetic response with the Panicoideae having a proportionally larger dead standing biomass and below-ground biomass than the non-Panicoideae. These results suggest that not only did the Panicoideae have a larger potential fuel load but that they also shunted carbon below-ground, enabling a fast recovery after being burned. The post-fire results were more strongly determined by phylogeny than by photosynthetic type. The Panicoideae recovered faster and more completely than the non-Panicoideae grasses, possibly contributing to their success and expansion under conditions of increased fire frequency. Although recovery of the and Panicoideae were similar, frequently burnt grasslands are dominated by the Panicoideae. Hence, this dominance cannot be explained by differences in their fire responses and may be determined by the post-fire environmental conditions that potentially advantage species possessing the photosynthetic pathway. Panicoideae dominance is limited to mesic environments where fire is the likely driver of grassland expansion while more arid environments are dominated by non-Panicoideae species. Representative species from these non-Panicoid subfamilies showed poor recovery after fire. This suggests that factors other than fire were the likely drivers of these xeric grassland expansions. The ability of these subfamilies, and particularly the species, to cope with drought remains a likely selective mechanism that requires further research.
- Full Text:
Phylogeography and epifauna of two intertidal seaweeds on the coast of South Africa
- Authors: Mmonwa, Lucas Kolobe
- Date: 2009
- Subjects: Phylogeography -- South Africa , Marine algae -- South Africa , Red algae -- South Africa , Gelidium -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5738 , http://hdl.handle.net/10962/d1005424 , Phylogeography -- South Africa , Marine algae -- South Africa , Red algae -- South Africa , Gelidium -- South Africa
- Description: Southern African biogeographic boundaries delimit the phylogeographic distribution of some coastal and estuarine invertebrates. This study investigated the impact of these boundaries on the phylogeographic distribution of two intertidal red seaweeds, Gelidium pristoides and Hypnea spicifera using the mitochondrial Cox2-3 spacer and the nuclear ITS1 regions. G. pristoides spores have short distance-dispersal, while long distance-dispersal is more likely in H. spicifera via spores and drifting fertile thallus fragments. Both markers revealed a south-western and south-eastern lineage within G. pristoides but the breaks between lineages do not coincide with any recognised biogeographic limits. The Cox2-3 spacer revealed a boundary between the two lineages at the Alexandria Coastal Dunefield (ACD) and ITS1 at the Gamtoos-Van Stadens Dunefields (GVD) which is approximately 80km west of the ACD. The minor difference between the two markers regarding location of the phylogeographic boundary is probably due to the dating differences between the two dunefields. The ACD as developed currently is superimposed on the ancient dunefields which formed during the Pleistocene, coinciding with the Cox2-3 spacer sequences divergence which dates back 500,000 - 580,000 years. The GVD formed during the Holocene (6,500 - 4,000 years ago), coinciding with the ITS1 sequences divergence which dates 4,224 - 4,928 years ago. Thus, these phylogeographic boundaries probably appeared without the influence of biogeographic boundaries, but rather due to the lack of suitable habitat in the dunefields, coupled with short dispersal-distances of the spores. Analysis of the ITS1 and Cox2-3 spacer regions in H. spicifera revealed that the species is characterized by uniform genetic structure along the coastline. This reflects the species`s potential for long range expansion as it inhabits both the intertidal and subtidal zones; and this presumably leads to high gene flow among populations. The ITS1 sequences showed minimal genetic variation of one substitution between the gametophyte and tetrasporophyte generations within H. spicifera. This suggests the predominance of asexual reproduction, which reduces gene flow and fixes alleles between generations. ANOSIM and Bray-Curtis cluster analyses showed scale-dependant variation in the abundances of epifauna (mainly amphipod, isopod, mollusc and polychaete species) on G. pristoides. At small local (within site) and large (among sites) scales, there were weak and no structure in epifaunal abundances respectively. However, at larger, biogeographic scales, samples from the same biogeographic region tended to be clustered together. Thus, there was a group containing predominantly south coast samples and a group containing east coast samples mixed with the remaining south coast samples. Such scale-dependant variation in epifaunal abundances is probably due to the effects of factors driving species richness at small local (within site) scales (e.g. wave exposure, seaweed biomass) and at larger, biogeographic scales (e.g. surface sea temperature). Moreover, at very small (individual samples) scales; there was no correlation between epifauna composition and genotype of the seaweed. Seaweed samples characterized by distinct ITS1 or Cox2-3 spacer sequences did not show any significant differences in epifaunal composition. Although the distributional pattern of the epifaunal community observed at large biogeographic scale is not clear, it seems to be associated with the biogeographic regions. However, phylogeographic distribution of Gelidium pristoides is not connected to biogeographic regions. Thus, at larger, biogeographic scales, there is no correlation between phylogeographic distribution of G. pristoides and distribution of the associated fauna
- Full Text:
- Authors: Mmonwa, Lucas Kolobe
- Date: 2009
- Subjects: Phylogeography -- South Africa , Marine algae -- South Africa , Red algae -- South Africa , Gelidium -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5738 , http://hdl.handle.net/10962/d1005424 , Phylogeography -- South Africa , Marine algae -- South Africa , Red algae -- South Africa , Gelidium -- South Africa
- Description: Southern African biogeographic boundaries delimit the phylogeographic distribution of some coastal and estuarine invertebrates. This study investigated the impact of these boundaries on the phylogeographic distribution of two intertidal red seaweeds, Gelidium pristoides and Hypnea spicifera using the mitochondrial Cox2-3 spacer and the nuclear ITS1 regions. G. pristoides spores have short distance-dispersal, while long distance-dispersal is more likely in H. spicifera via spores and drifting fertile thallus fragments. Both markers revealed a south-western and south-eastern lineage within G. pristoides but the breaks between lineages do not coincide with any recognised biogeographic limits. The Cox2-3 spacer revealed a boundary between the two lineages at the Alexandria Coastal Dunefield (ACD) and ITS1 at the Gamtoos-Van Stadens Dunefields (GVD) which is approximately 80km west of the ACD. The minor difference between the two markers regarding location of the phylogeographic boundary is probably due to the dating differences between the two dunefields. The ACD as developed currently is superimposed on the ancient dunefields which formed during the Pleistocene, coinciding with the Cox2-3 spacer sequences divergence which dates back 500,000 - 580,000 years. The GVD formed during the Holocene (6,500 - 4,000 years ago), coinciding with the ITS1 sequences divergence which dates 4,224 - 4,928 years ago. Thus, these phylogeographic boundaries probably appeared without the influence of biogeographic boundaries, but rather due to the lack of suitable habitat in the dunefields, coupled with short dispersal-distances of the spores. Analysis of the ITS1 and Cox2-3 spacer regions in H. spicifera revealed that the species is characterized by uniform genetic structure along the coastline. This reflects the species`s potential for long range expansion as it inhabits both the intertidal and subtidal zones; and this presumably leads to high gene flow among populations. The ITS1 sequences showed minimal genetic variation of one substitution between the gametophyte and tetrasporophyte generations within H. spicifera. This suggests the predominance of asexual reproduction, which reduces gene flow and fixes alleles between generations. ANOSIM and Bray-Curtis cluster analyses showed scale-dependant variation in the abundances of epifauna (mainly amphipod, isopod, mollusc and polychaete species) on G. pristoides. At small local (within site) and large (among sites) scales, there were weak and no structure in epifaunal abundances respectively. However, at larger, biogeographic scales, samples from the same biogeographic region tended to be clustered together. Thus, there was a group containing predominantly south coast samples and a group containing east coast samples mixed with the remaining south coast samples. Such scale-dependant variation in epifaunal abundances is probably due to the effects of factors driving species richness at small local (within site) scales (e.g. wave exposure, seaweed biomass) and at larger, biogeographic scales (e.g. surface sea temperature). Moreover, at very small (individual samples) scales; there was no correlation between epifauna composition and genotype of the seaweed. Seaweed samples characterized by distinct ITS1 or Cox2-3 spacer sequences did not show any significant differences in epifaunal composition. Although the distributional pattern of the epifaunal community observed at large biogeographic scale is not clear, it seems to be associated with the biogeographic regions. However, phylogeographic distribution of Gelidium pristoides is not connected to biogeographic regions. Thus, at larger, biogeographic scales, there is no correlation between phylogeographic distribution of G. pristoides and distribution of the associated fauna
- Full Text:
Polymers, catalysts and nanostructures a hybrid approach to biomolecule detection
- Authors: Frith, Kelly-Anne
- Date: 2009
- Subjects: Polymers , Nanostructured materials , Biomolecules , Tryptophan , Melatonin , Electrodes , Electrochemistry , Tryptophan oxygenase
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3980 , http://hdl.handle.net/10962/d1004039 , Polymers , Nanostructured materials , Biomolecules , Tryptophan , Melatonin , Electrodes , Electrochemistry , Tryptophan oxygenase
- Description: The main goals in electroanalytical sensing are towards improved sensitivity and selectivity, or specificity, of an analyte. There are several approaches to achieving these goals with the main approach being modification of an electrode surface with synthetic or natural catalysts (enzymes), polymers and also utilisation of nanostructured materials. At present, there is a strong movement towards hybrid sensing which couple different properties of two or more surface modification approaches. In this thesis, a range of these surface modifications were explored for analysis and detection of two main analytes: the amino acid, tryptophan (Trp); and, the neurotransmitter, dopamine (DA). Specifically, this thesis aimed to utilise these methods to enhance the sensitivity and selectivity for Trp over an interferent, the indoleamine, melatonin (Mel); and, DA over the vitamin, ascorbic acid (AA). For Trp detection, immobilisation of an enzyme, Tryptophanase (Trpase) resulted in poor selectivity for the analyte. However, enhanced sensitivity and selectivity was achieved through pH manipulation of the electrolyte medium at a Nafion®-modified electrode surface for both Trp and Mel. At pH 3.0, the Mel and Trp anodic peak potentials were sufficiently resolved allowing for an LOD of 1.60 and 1.62 nM,respectively, and permitting the accurate analysis of Trp in a dietary supplement containing Mel. Multi-walled carbon nanotubes (MWCNTs) suspended in Nafion® exhibited further increases in the signal responses of these analytes at pH 3.0 and 7.4 with minimal change in the resolution of the anodic peaks. A lower sensitivity was, therefore, observed at the Nafion® and MWCNT modified electrode compared to the Nafion®-modified electrode at pH 3.0 with LODs of 0.59 and 0.80 nM exhibited for Trp and Mel, respectively. Enhanced selectivity for Trp in the presence of Mel can be achieved with MWCNTs in the presence of metallotetrasulphonated phthalocyanines (MTSPcs) particularly at pH 3.0, owing to cation exchange effects. However, the lack of sensitivity towards Trp, and even Mel, at this CoTSPc and MWCNT modified electrode remains a drawback. For DA, detection at the MWCNT and Nafion® surface resulted in improved sensitivity over that of both the bare electrode (613.0 nM) and the Nafion® modified electrode (1045.1 nM) with a calculated LOD of 133.9 nM at this layer. Furthermore, improvements in the selectivity of DA were achieved at the Nafion® and MWCNT modified electrode as exclusion of AA (150 μM) was achieved. At the MWCNT and CoTSPc surface, AA was excluded up to 130 μM with sensitivity for DA extending as low as 14.3 nM, far greater than observed for Trp and Mel. These concentrations are well within physiological concentration ranges and represent the most significant solution yet in terms of AA exclusion and enhanced sensitivity for DA. An examination of the surface layering by impedance spectroscopy and atomic force microscopy indicates that the success of the hybrid sensor utilising CoTSPc and MWCNTs lay in improved dispersion of MWCNTs and improved electron transfer kinetics, facilitated by the net charge of the materials present. This thesis, thus, showed the utility of a judicious selection of synthetic and biological catalysts, polymers and carbon nanomaterials towards a hybrid approach to the electrochemical sensing of Trp, Mel, DA and AA with focus on sensitivity and selectivity of these analytes.
- Full Text:
- Authors: Frith, Kelly-Anne
- Date: 2009
- Subjects: Polymers , Nanostructured materials , Biomolecules , Tryptophan , Melatonin , Electrodes , Electrochemistry , Tryptophan oxygenase
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3980 , http://hdl.handle.net/10962/d1004039 , Polymers , Nanostructured materials , Biomolecules , Tryptophan , Melatonin , Electrodes , Electrochemistry , Tryptophan oxygenase
- Description: The main goals in electroanalytical sensing are towards improved sensitivity and selectivity, or specificity, of an analyte. There are several approaches to achieving these goals with the main approach being modification of an electrode surface with synthetic or natural catalysts (enzymes), polymers and also utilisation of nanostructured materials. At present, there is a strong movement towards hybrid sensing which couple different properties of two or more surface modification approaches. In this thesis, a range of these surface modifications were explored for analysis and detection of two main analytes: the amino acid, tryptophan (Trp); and, the neurotransmitter, dopamine (DA). Specifically, this thesis aimed to utilise these methods to enhance the sensitivity and selectivity for Trp over an interferent, the indoleamine, melatonin (Mel); and, DA over the vitamin, ascorbic acid (AA). For Trp detection, immobilisation of an enzyme, Tryptophanase (Trpase) resulted in poor selectivity for the analyte. However, enhanced sensitivity and selectivity was achieved through pH manipulation of the electrolyte medium at a Nafion®-modified electrode surface for both Trp and Mel. At pH 3.0, the Mel and Trp anodic peak potentials were sufficiently resolved allowing for an LOD of 1.60 and 1.62 nM,respectively, and permitting the accurate analysis of Trp in a dietary supplement containing Mel. Multi-walled carbon nanotubes (MWCNTs) suspended in Nafion® exhibited further increases in the signal responses of these analytes at pH 3.0 and 7.4 with minimal change in the resolution of the anodic peaks. A lower sensitivity was, therefore, observed at the Nafion® and MWCNT modified electrode compared to the Nafion®-modified electrode at pH 3.0 with LODs of 0.59 and 0.80 nM exhibited for Trp and Mel, respectively. Enhanced selectivity for Trp in the presence of Mel can be achieved with MWCNTs in the presence of metallotetrasulphonated phthalocyanines (MTSPcs) particularly at pH 3.0, owing to cation exchange effects. However, the lack of sensitivity towards Trp, and even Mel, at this CoTSPc and MWCNT modified electrode remains a drawback. For DA, detection at the MWCNT and Nafion® surface resulted in improved sensitivity over that of both the bare electrode (613.0 nM) and the Nafion® modified electrode (1045.1 nM) with a calculated LOD of 133.9 nM at this layer. Furthermore, improvements in the selectivity of DA were achieved at the Nafion® and MWCNT modified electrode as exclusion of AA (150 μM) was achieved. At the MWCNT and CoTSPc surface, AA was excluded up to 130 μM with sensitivity for DA extending as low as 14.3 nM, far greater than observed for Trp and Mel. These concentrations are well within physiological concentration ranges and represent the most significant solution yet in terms of AA exclusion and enhanced sensitivity for DA. An examination of the surface layering by impedance spectroscopy and atomic force microscopy indicates that the success of the hybrid sensor utilising CoTSPc and MWCNTs lay in improved dispersion of MWCNTs and improved electron transfer kinetics, facilitated by the net charge of the materials present. This thesis, thus, showed the utility of a judicious selection of synthetic and biological catalysts, polymers and carbon nanomaterials towards a hybrid approach to the electrochemical sensing of Trp, Mel, DA and AA with focus on sensitivity and selectivity of these analytes.
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Predictability of Geomagnetically Induced Currents using neural networks
- Authors: Lotz, Stefan
- Date: 2009
- Subjects: Advanced Composition Explorer (Artificial satellite) , Geomagnetism , Electromagnetic induction , Neural networks (Computer science) , Artificial intelligence
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5483 , http://hdl.handle.net/10962/d1005269 , Advanced Composition Explorer (Artificial satellite) , Geomagnetism , Electromagnetic induction , Neural networks (Computer science) , Artificial intelligence
- Description: It is a well documented fact that Geomagnetically Induced Currents (GIC’s) poses a significant threat to ground-based electric conductor networks like oil pipelines, railways and powerline networks. A study is undertaken to determine the feasibility of using artificial neural network models to predict GIC occurrence in the Southern African power grid. The magnitude of an induced current at a specific location on the Earth’s surface is directly related to the temporal derivative of the geomagnetic field (specifically its horizontal components) at that point. Hence, the focus of the problem is on the prediction of the temporal variations in the horizontal geomagnetic field (@Bx/@t and @By/@t). Artificial neural networks are used to predict @Bx/@t and @By/@t measured at Hermanus, South Africa (34.27◦ S, 19.12◦ E) with a 30 minute prediction lead time. As input parameters to the neural networks, insitu solar wind measurements made by the Advanced Composition Explorer (ACE) satellite are used. The results presented here compare well with similar models developed at high-latitude locations (e.g. Sweden, Finland, Canada) where extensive GIC research has been undertaken. It is concluded that it would indeed be feasible to use a neural network model to predict GIC occurrence in the Southern African power grid, provided that GIC measurements, powerline configuration and network parameters are made available.
- Full Text:
- Authors: Lotz, Stefan
- Date: 2009
- Subjects: Advanced Composition Explorer (Artificial satellite) , Geomagnetism , Electromagnetic induction , Neural networks (Computer science) , Artificial intelligence
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5483 , http://hdl.handle.net/10962/d1005269 , Advanced Composition Explorer (Artificial satellite) , Geomagnetism , Electromagnetic induction , Neural networks (Computer science) , Artificial intelligence
- Description: It is a well documented fact that Geomagnetically Induced Currents (GIC’s) poses a significant threat to ground-based electric conductor networks like oil pipelines, railways and powerline networks. A study is undertaken to determine the feasibility of using artificial neural network models to predict GIC occurrence in the Southern African power grid. The magnitude of an induced current at a specific location on the Earth’s surface is directly related to the temporal derivative of the geomagnetic field (specifically its horizontal components) at that point. Hence, the focus of the problem is on the prediction of the temporal variations in the horizontal geomagnetic field (@Bx/@t and @By/@t). Artificial neural networks are used to predict @Bx/@t and @By/@t measured at Hermanus, South Africa (34.27◦ S, 19.12◦ E) with a 30 minute prediction lead time. As input parameters to the neural networks, insitu solar wind measurements made by the Advanced Composition Explorer (ACE) satellite are used. The results presented here compare well with similar models developed at high-latitude locations (e.g. Sweden, Finland, Canada) where extensive GIC research has been undertaken. It is concluded that it would indeed be feasible to use a neural network model to predict GIC occurrence in the Southern African power grid, provided that GIC measurements, powerline configuration and network parameters are made available.
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Preservation or exploitation? : a study of the development of the mining rights legislation on the Witwatersrand goldfields from 1886 to 2008
- Authors: Stott, Joan
- Date: 2009
- Subjects: Ostrom, Elinor Chamber of Mines of South Africa Gold mines and mining -- South Africa -- Witwatersrand -- History Mineral industries -- Finance -- South Africa Mining law -- South Africa
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:988 , http://hdl.handle.net/10962/d1002723
- Description: Elinor Ostrom (2005: 238) assumes that in understanding the make up and behaviour of institutional systems governing natural resources: “Resource users are explicitly thought of as rational egoists who plunder local resources so as to maximise their own short-term benefits. Government officials are implicitly depicted, on the other hand, as seeking, the more general public interest, having the relevant information at hand and the capability of designing optimal policies.” This thesis examines the validity of this assumption through an historical analysis of the deep-level gold mining industry of the Witwatersrand, South Africa. The main focus of the assessment is on the institutions of ownership – that is, the development of mining rights and title legislation between 1886 and 2008. The study looks at the legislations’ transformation and implementation from the perspective of the gold mining industry – made up of the mining finance houses and the Chamber of Mines of South Africa – and that of the state. The transformation of the mining industry’s institutional framework was both a choice by government as well as that of the firms in the mining industry. The theoretical framework is constructed from four areas of economic thought. These include: the neoclassical and Keynesian schools of macroeconomic thought; industrial organisation and its relevance to the relationship between firms and the market; institutional and new institutional economics; and finally property rights. The determinants of policy design and the impact of such design on firms and industry is examined. The development, implementation and use of the aforementioned legislation is examined from two perspectives, namely, that of preserver or exploiter. Throughout the history of this prominent South African industry, the motivation for action from the industry or government has oscillated between the two extremes of preserver or exploiter over the time period examined. The conclusion is drawn on an overall and broad focus of actions – with a strong focus on the most recent developments in mining legislation – post-1992.
- Full Text:
- Authors: Stott, Joan
- Date: 2009
- Subjects: Ostrom, Elinor Chamber of Mines of South Africa Gold mines and mining -- South Africa -- Witwatersrand -- History Mineral industries -- Finance -- South Africa Mining law -- South Africa
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:988 , http://hdl.handle.net/10962/d1002723
- Description: Elinor Ostrom (2005: 238) assumes that in understanding the make up and behaviour of institutional systems governing natural resources: “Resource users are explicitly thought of as rational egoists who plunder local resources so as to maximise their own short-term benefits. Government officials are implicitly depicted, on the other hand, as seeking, the more general public interest, having the relevant information at hand and the capability of designing optimal policies.” This thesis examines the validity of this assumption through an historical analysis of the deep-level gold mining industry of the Witwatersrand, South Africa. The main focus of the assessment is on the institutions of ownership – that is, the development of mining rights and title legislation between 1886 and 2008. The study looks at the legislations’ transformation and implementation from the perspective of the gold mining industry – made up of the mining finance houses and the Chamber of Mines of South Africa – and that of the state. The transformation of the mining industry’s institutional framework was both a choice by government as well as that of the firms in the mining industry. The theoretical framework is constructed from four areas of economic thought. These include: the neoclassical and Keynesian schools of macroeconomic thought; industrial organisation and its relevance to the relationship between firms and the market; institutional and new institutional economics; and finally property rights. The determinants of policy design and the impact of such design on firms and industry is examined. The development, implementation and use of the aforementioned legislation is examined from two perspectives, namely, that of preserver or exploiter. Throughout the history of this prominent South African industry, the motivation for action from the industry or government has oscillated between the two extremes of preserver or exploiter over the time period examined. The conclusion is drawn on an overall and broad focus of actions – with a strong focus on the most recent developments in mining legislation – post-1992.
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Protein secondary structure prediction using neural networks and support vector machines
- Authors: Tsilo, Lipontseng Cecilia
- Date: 2009
- Subjects: Neural networks (Computer science) , Support vector machines , Proteins -- Structure -- Mathematical models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5569 , http://hdl.handle.net/10962/d1002809 , Neural networks (Computer science) , Support vector machines , Proteins -- Structure -- Mathematical models
- Description: Predicting the secondary structure of proteins is important in biochemistry because the 3D structure can be determined from the local folds that are found in secondary structures. Moreover, knowing the tertiary structure of proteins can assist in determining their functions. The objective of this thesis is to compare the performance of Neural Networks (NN) and Support Vector Machines (SVM) in predicting the secondary structure of 62 globular proteins from their primary sequence. For each NN and SVM, we created six binary classifiers to distinguish between the classes’ helices (H) strand (E), and coil (C). For NN we use Resilient Backpropagation training with and without early stopping. We use NN with either no hidden layer or with one hidden layer with 1,2,...,40 hidden neurons. For SVM we use a Gaussian kernel with parameter fixed at = 0.1 and varying cost parameters C in the range [0.1,5]. 10- fold cross-validation is used to obtain overall estimates for the probability of making a correct prediction. Our experiments indicate for NN and SVM that the different binary classifiers have varying accuracies: from 69% correct predictions for coils vs. non-coil up to 80% correct predictions for stand vs. non-strand. It is further demonstrated that NN with no hidden layer or not more than 2 hidden neurons in the hidden layer are sufficient for better predictions. For SVM we show that the estimated accuracies do not depend on the value of the cost parameter. As a major result, we will demonstrate that the accuracy estimates of NN and SVM binary classifiers cannot distinguish. This contradicts a modern belief in bioinformatics that SVM outperforms other predictors.
- Full Text:
- Authors: Tsilo, Lipontseng Cecilia
- Date: 2009
- Subjects: Neural networks (Computer science) , Support vector machines , Proteins -- Structure -- Mathematical models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5569 , http://hdl.handle.net/10962/d1002809 , Neural networks (Computer science) , Support vector machines , Proteins -- Structure -- Mathematical models
- Description: Predicting the secondary structure of proteins is important in biochemistry because the 3D structure can be determined from the local folds that are found in secondary structures. Moreover, knowing the tertiary structure of proteins can assist in determining their functions. The objective of this thesis is to compare the performance of Neural Networks (NN) and Support Vector Machines (SVM) in predicting the secondary structure of 62 globular proteins from their primary sequence. For each NN and SVM, we created six binary classifiers to distinguish between the classes’ helices (H) strand (E), and coil (C). For NN we use Resilient Backpropagation training with and without early stopping. We use NN with either no hidden layer or with one hidden layer with 1,2,...,40 hidden neurons. For SVM we use a Gaussian kernel with parameter fixed at = 0.1 and varying cost parameters C in the range [0.1,5]. 10- fold cross-validation is used to obtain overall estimates for the probability of making a correct prediction. Our experiments indicate for NN and SVM that the different binary classifiers have varying accuracies: from 69% correct predictions for coils vs. non-coil up to 80% correct predictions for stand vs. non-strand. It is further demonstrated that NN with no hidden layer or not more than 2 hidden neurons in the hidden layer are sufficient for better predictions. For SVM we show that the estimated accuracies do not depend on the value of the cost parameter. As a major result, we will demonstrate that the accuracy estimates of NN and SVM binary classifiers cannot distinguish. This contradicts a modern belief in bioinformatics that SVM outperforms other predictors.
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Public discourses on choice of termination of pregnancy in a rural area of the Eastern Cape Province in South Africa
- Authors: Sigcau, Nomakhosi
- Date: 2009
- Subjects: Abortion -- South Africa -- Eastern Cape Abortion -- Public opinion Abortion -- Moral and ethical aspects Abortion -- Social aspects Abortion -- Psychological aspects Discourse analysis -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3055 , http://hdl.handle.net/10962/d1002564
- Description: A period of ten years has elapsed since the Choice on Termination of Pregnancy Act came into effect. Little has been done in South Africa to investigate public discourses concerning termination of pregnancy since the implementation of the Act. The social context and the quality of available support systems determine the outcome of the women’s feelings after the abortion. Knowledge about the social context is important, as it will help to understand the complexities and nuances of abortion. The aim of the research is to explore public discourses on Choice on Termination of Pregnancy (CTOP), and the potential implications of these discourses on the use of the CTOP service. The sample consisted of 23 black isiXhosa-speaking participants from the rural area of the Eastern Cape Province in South Africa. Four focus groups coming from different age groups (between the ages 18 and 52) with both men and women participated in the study. Fictitious vignettes that tap into two different scenarios regarding abortion based on women’s stories were used. Discourses that emerged from people’s text are explained, described and interpreted through a discourse analysis. Since the study was interested in public discourses it led to the discovery of 17 interpretative repertoires as follows: social stigma, abortion equated to murder, degradation of society, pregnancy as an irresponsible act, conditional acceptance, TOP in the context of marriage, future potentiality invested in the foetus, dehumanizing foetus into a clot, shared decision making responsibility, gender dynamics interpretative repertoire, negative post abortion consequences, the scolding versus the supportive nurse interpretative repertoire, alternatives interpretative repertoire, rights versus no responsibility interpretative repertoire, more knowledge needed, male and female or generational differentiation repertoire, and the positive effects repertoire. Abortion is opposed on religious and cultural grounds. TOP has been legalized in South Africa but with this a debate and conflicting views have arisen. These variations in people’s discourses may limit access to TOP for women who need the service.
- Full Text:
- Authors: Sigcau, Nomakhosi
- Date: 2009
- Subjects: Abortion -- South Africa -- Eastern Cape Abortion -- Public opinion Abortion -- Moral and ethical aspects Abortion -- Social aspects Abortion -- Psychological aspects Discourse analysis -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3055 , http://hdl.handle.net/10962/d1002564
- Description: A period of ten years has elapsed since the Choice on Termination of Pregnancy Act came into effect. Little has been done in South Africa to investigate public discourses concerning termination of pregnancy since the implementation of the Act. The social context and the quality of available support systems determine the outcome of the women’s feelings after the abortion. Knowledge about the social context is important, as it will help to understand the complexities and nuances of abortion. The aim of the research is to explore public discourses on Choice on Termination of Pregnancy (CTOP), and the potential implications of these discourses on the use of the CTOP service. The sample consisted of 23 black isiXhosa-speaking participants from the rural area of the Eastern Cape Province in South Africa. Four focus groups coming from different age groups (between the ages 18 and 52) with both men and women participated in the study. Fictitious vignettes that tap into two different scenarios regarding abortion based on women’s stories were used. Discourses that emerged from people’s text are explained, described and interpreted through a discourse analysis. Since the study was interested in public discourses it led to the discovery of 17 interpretative repertoires as follows: social stigma, abortion equated to murder, degradation of society, pregnancy as an irresponsible act, conditional acceptance, TOP in the context of marriage, future potentiality invested in the foetus, dehumanizing foetus into a clot, shared decision making responsibility, gender dynamics interpretative repertoire, negative post abortion consequences, the scolding versus the supportive nurse interpretative repertoire, alternatives interpretative repertoire, rights versus no responsibility interpretative repertoire, more knowledge needed, male and female or generational differentiation repertoire, and the positive effects repertoire. Abortion is opposed on religious and cultural grounds. TOP has been legalized in South Africa but with this a debate and conflicting views have arisen. These variations in people’s discourses may limit access to TOP for women who need the service.
- Full Text:
Purification and characterization of fructosyltransferase for the synthesis of short-chain fructo-oligosaccharides and investigation into thier anti-carcinogenic properties
- Authors: Nemukula, Aluwani
- Date: 2009
- Subjects: Oligosaccharides , Polygalacturonase , Aspergillus , Fructose , Inulin , Cancer -- Prevention , Cancer -- Research , Carcinogens , High performance liquid chromatography
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3927 , http://hdl.handle.net/10962/d1003986 , Oligosaccharides , Polygalacturonase , Aspergillus , Fructose , Inulin , Cancer -- Prevention , Cancer -- Research , Carcinogens , High performance liquid chromatography
- Description: There is a growing attention in the synthesis of fructo-oligosaccharides (FOS) due to their excellent bio-functional and health-promoting properties. The current production processes are limited to chemical hydrolysis reactions of plant extracts, which are often associated with several drawbacks. In this study, fructosyltransferase (FTase) and polygalacturonase (PGase) activities, present in a commercial enzyme preparation (Pectinex® Ultra SP-L) sourced from Aspergillus aculeatus, have been separated and fully purified by anion-exchange and sizeexclusion chromatography. The FTase possesses fructosyl transfer activity for FOS synthesis and the PGase has pectin hydrolytic activity. Fructosyltransferase is a single-band protein with a molecular weight of 85 kDa, whereas PGase is a distinct protein of 40 kDa. The temperature and pH optima of FTase were 60 ºC and 6.0, with a half-life of 8 h; while that for PGase were 40 ºC and 6.0, respectively. FTase was slightly inhibited in the presence of Ni²⁺, Mg²⁺ and urea; but PGase was more susceptible to divalent ions such as Ca²⁺, Mg²⁺ and Mn²⁺. The kinetic parameters (Km and Vmax) of FTase for the hydrolysis of β-(2→1) linkages from sucrose were 752.3 mM and 120.5 μmol.min⁻¹.mL⁻¹, respectively; whereas the same parameters for pectin hydrolysis by PGase were 13.0 mg.mL⁻¹ and 263 μmol.min-1.mL⁻¹, respectively. The purified FTase was able to transfer fructosyl residues from sucrose, synthesizing the corresponding chains of FOS. PGase was relatively stable at 40 ºC (t½ > 3 h), depolymerizing the pectin backbone while releasing the inulins from within the chicory roots. Analysis of various mixtures of FOS by mass spectrometry, HPLC and ¹H-NMR was undertaken. Results indicated that MS with electrospray ionization and ¹H-NMR are capable of providing relative quantitative data of the FOS present in the mixtures. The pharmaceutical effects of various sc-FOS (0.5%, v/v) and SCFA (0.3%, v/v) on certain bacterial enzymes (β-glucuronidase, urease and β-glucosidase) associated with the formation of carcinogens were also studied. These enzyme activities were not directly influenced by the sc-FOS, but were found to be remarkably decreased by SCFA, pointing toward the prebiotic effect of FOS in intestinal microflora modulation.
- Full Text:
- Authors: Nemukula, Aluwani
- Date: 2009
- Subjects: Oligosaccharides , Polygalacturonase , Aspergillus , Fructose , Inulin , Cancer -- Prevention , Cancer -- Research , Carcinogens , High performance liquid chromatography
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3927 , http://hdl.handle.net/10962/d1003986 , Oligosaccharides , Polygalacturonase , Aspergillus , Fructose , Inulin , Cancer -- Prevention , Cancer -- Research , Carcinogens , High performance liquid chromatography
- Description: There is a growing attention in the synthesis of fructo-oligosaccharides (FOS) due to their excellent bio-functional and health-promoting properties. The current production processes are limited to chemical hydrolysis reactions of plant extracts, which are often associated with several drawbacks. In this study, fructosyltransferase (FTase) and polygalacturonase (PGase) activities, present in a commercial enzyme preparation (Pectinex® Ultra SP-L) sourced from Aspergillus aculeatus, have been separated and fully purified by anion-exchange and sizeexclusion chromatography. The FTase possesses fructosyl transfer activity for FOS synthesis and the PGase has pectin hydrolytic activity. Fructosyltransferase is a single-band protein with a molecular weight of 85 kDa, whereas PGase is a distinct protein of 40 kDa. The temperature and pH optima of FTase were 60 ºC and 6.0, with a half-life of 8 h; while that for PGase were 40 ºC and 6.0, respectively. FTase was slightly inhibited in the presence of Ni²⁺, Mg²⁺ and urea; but PGase was more susceptible to divalent ions such as Ca²⁺, Mg²⁺ and Mn²⁺. The kinetic parameters (Km and Vmax) of FTase for the hydrolysis of β-(2→1) linkages from sucrose were 752.3 mM and 120.5 μmol.min⁻¹.mL⁻¹, respectively; whereas the same parameters for pectin hydrolysis by PGase were 13.0 mg.mL⁻¹ and 263 μmol.min-1.mL⁻¹, respectively. The purified FTase was able to transfer fructosyl residues from sucrose, synthesizing the corresponding chains of FOS. PGase was relatively stable at 40 ºC (t½ > 3 h), depolymerizing the pectin backbone while releasing the inulins from within the chicory roots. Analysis of various mixtures of FOS by mass spectrometry, HPLC and ¹H-NMR was undertaken. Results indicated that MS with electrospray ionization and ¹H-NMR are capable of providing relative quantitative data of the FOS present in the mixtures. The pharmaceutical effects of various sc-FOS (0.5%, v/v) and SCFA (0.3%, v/v) on certain bacterial enzymes (β-glucuronidase, urease and β-glucosidase) associated with the formation of carcinogens were also studied. These enzyme activities were not directly influenced by the sc-FOS, but were found to be remarkably decreased by SCFA, pointing toward the prebiotic effect of FOS in intestinal microflora modulation.
- Full Text:
Racism and law : implementing the right to equality in selected South African equality courts
- Authors: Krüger, Rósaan
- Date: 2009
- Subjects: South Africa Promotion of Equality and Prevention of Unfair Discrimination Act, 2000 , Equality -- South Africa , Discrimination -- Law and legislation -- South Africa , Racism -- Law and legislation -- South Africa , Apartheid -- Law and legislation -- South Africa , Constitutional law -- South Africa , South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3677 , http://hdl.handle.net/10962/d1003192 , South Africa Promotion of Equality and Prevention of Unfair Discrimination Act, 2000 , Equality -- South Africa , Discrimination -- Law and legislation -- South Africa , Racism -- Law and legislation -- South Africa , Apartheid -- Law and legislation -- South Africa , Constitutional law -- South Africa , South Africa -- Politics and government -- 1994-
- Description: Racism has informed South African society since colonial times. Racist beliefs found expression in the laws of colonial and apartheid South Africa and shaped both state and society. The constitutional state that South Africa has become since 1994, is based on the values of ‘human dignity’, ‘the achievement of equality’ and ‘nonracialism’, among others. Law formed the basis of the racist state prior to 1994, and now law has a fundamental role to play in the transformation of the state and society in an egalitarian direction by addressing socio-economic inequalities on the one hand, and by changing patterns of behaviour based on racist beliefs forged in the past, on the other. This thesis examines one of the legal instruments that is intended to contribute to transformation in the latter sense, namely the Promotion of Equality and Prevention of Unfair Discrimination Act 4 of 2000 (the Equality Act), with specific reference to the issue of racism. The provisions of this Act and the framework for its operation against the background of South Africa’s racist past, and within the broader framework of international and constitutional law, are examined. These two legal frameworks are analysed for the purpose of determining the standards set by international and constitutional law regarding racial equality in order to determine whether the Equality Act measures up. This thesis also incorporates an analysis of the practical application of the provisions of the Equality Act to complaints of racism in selected equality courts. The theoretical analysis of the Act’s provisions and their application in the equality courts point to various problematic formulations and obstacles which negatively affect the application of the provisions and thus hamper social change. The thesis concludes with recommendations for refining the Act’s provisions and its application.
- Full Text:
- Authors: Krüger, Rósaan
- Date: 2009
- Subjects: South Africa Promotion of Equality and Prevention of Unfair Discrimination Act, 2000 , Equality -- South Africa , Discrimination -- Law and legislation -- South Africa , Racism -- Law and legislation -- South Africa , Apartheid -- Law and legislation -- South Africa , Constitutional law -- South Africa , South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3677 , http://hdl.handle.net/10962/d1003192 , South Africa Promotion of Equality and Prevention of Unfair Discrimination Act, 2000 , Equality -- South Africa , Discrimination -- Law and legislation -- South Africa , Racism -- Law and legislation -- South Africa , Apartheid -- Law and legislation -- South Africa , Constitutional law -- South Africa , South Africa -- Politics and government -- 1994-
- Description: Racism has informed South African society since colonial times. Racist beliefs found expression in the laws of colonial and apartheid South Africa and shaped both state and society. The constitutional state that South Africa has become since 1994, is based on the values of ‘human dignity’, ‘the achievement of equality’ and ‘nonracialism’, among others. Law formed the basis of the racist state prior to 1994, and now law has a fundamental role to play in the transformation of the state and society in an egalitarian direction by addressing socio-economic inequalities on the one hand, and by changing patterns of behaviour based on racist beliefs forged in the past, on the other. This thesis examines one of the legal instruments that is intended to contribute to transformation in the latter sense, namely the Promotion of Equality and Prevention of Unfair Discrimination Act 4 of 2000 (the Equality Act), with specific reference to the issue of racism. The provisions of this Act and the framework for its operation against the background of South Africa’s racist past, and within the broader framework of international and constitutional law, are examined. These two legal frameworks are analysed for the purpose of determining the standards set by international and constitutional law regarding racial equality in order to determine whether the Equality Act measures up. This thesis also incorporates an analysis of the practical application of the provisions of the Equality Act to complaints of racism in selected equality courts. The theoretical analysis of the Act’s provisions and their application in the equality courts point to various problematic formulations and obstacles which negatively affect the application of the provisions and thus hamper social change. The thesis concludes with recommendations for refining the Act’s provisions and its application.
- Full Text:
Recontextualising issues in the 'NISTCOL" environmental education curriculum module for Primary Diploma by Distance Learning in Zambia
- Authors: Moose, John
- Date: 2009
- Subjects: Environmental education -- Zambia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1722 , http://hdl.handle.net/10962/d1003605
- Description: This study investigated the recontextualising of the NISTCOL environmental education curriculum module for the Primary Teachers’ Diploma by Distance Learning (PTDDL) in Zambia. It focused on three case sites, the NISTCOL EE curriculum module for PTDDL and the University of Zambia, the National In-Service Teacher’s College (NISTCOL) and four basic schools: chalimbana, Bimbe, Chongwe and Silver Rest. The study looked at teacher professional development in environmental education in Zambia. The aims and goals were to investigate the NISTCOL EE curriculum and identifying issues that were associated with lecturers in the recontextualising process and further examine what issues were associated with curriculum recontextualisation in Zambian schools. For the conceptual constructs, the research drew on Bernstein’s (1990) framework of pedagogic discourse, it traced how the pedagogic discourse was de-located from the field of production and re-located into the pedagogic practice of each stated case above. It further examined the continuities, discontinuities and changes in the official environmental discourse as it was recontextualised. The study particularly focused on Bernstein’s conceptual constructs of selective appropriation and ideological transformation. In each case the Bernstein framework is used to analyze the process to identify recontextualising issues influencing pedagogical practice in the Zambian schools and college. The study revealed that each case under focus was unique but through examining the environmental discourse and pedagogical discourse in each case recontextalising issues were identified. Each case was influenced by different factors, such as lack of policy synergy, lack of EE vision at national level in Zambia, experience and knowledge, ideologies and emphasis, and depth of engagement. These factors provided me with a deeper insight into the curriculum recontextualising processes in Zambian schools.
- Full Text:
- Authors: Moose, John
- Date: 2009
- Subjects: Environmental education -- Zambia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1722 , http://hdl.handle.net/10962/d1003605
- Description: This study investigated the recontextualising of the NISTCOL environmental education curriculum module for the Primary Teachers’ Diploma by Distance Learning (PTDDL) in Zambia. It focused on three case sites, the NISTCOL EE curriculum module for PTDDL and the University of Zambia, the National In-Service Teacher’s College (NISTCOL) and four basic schools: chalimbana, Bimbe, Chongwe and Silver Rest. The study looked at teacher professional development in environmental education in Zambia. The aims and goals were to investigate the NISTCOL EE curriculum and identifying issues that were associated with lecturers in the recontextualising process and further examine what issues were associated with curriculum recontextualisation in Zambian schools. For the conceptual constructs, the research drew on Bernstein’s (1990) framework of pedagogic discourse, it traced how the pedagogic discourse was de-located from the field of production and re-located into the pedagogic practice of each stated case above. It further examined the continuities, discontinuities and changes in the official environmental discourse as it was recontextualised. The study particularly focused on Bernstein’s conceptual constructs of selective appropriation and ideological transformation. In each case the Bernstein framework is used to analyze the process to identify recontextualising issues influencing pedagogical practice in the Zambian schools and college. The study revealed that each case under focus was unique but through examining the environmental discourse and pedagogical discourse in each case recontextalising issues were identified. Each case was influenced by different factors, such as lack of policy synergy, lack of EE vision at national level in Zambia, experience and knowledge, ideologies and emphasis, and depth of engagement. These factors provided me with a deeper insight into the curriculum recontextualising processes in Zambian schools.
- Full Text:
Redress : debates informing exhibitions and acquisitions in selected South African public art galleries (1990-1994)
- Authors: Cook, Shashi Chailey
- Date: 2009
- Subjects: South African National Gallery Exhibitions Durban Art Gallery Exhibitions Joahnnesburg Art Gallery Exhibitions Art -- South Africa -- Exhibitions Art, South African Exhibitions South Africa History Exhibitions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2399 , http://hdl.handle.net/10962/d1002195
- Description: This thesis centres on the debates informing the progress of three public art galleries in South Africa between 1990 and 1994. This was a period of great change in the country, spanning from the unbanning of left-wing political parties and Nelson Mandela’s release from prison, to the first democratic elections which resulted in his inauguration as President of South Africa. The study focuses specifically on the Johannesburg Art Gallery, the South African National Gallery, and the Durban Art Gallery, delineating the events and exhibitions held, the programmes initiated, and the artists represented by these galleries during this post-apartheid/pre-democracy phase of the country’s history. The debates relevant to these galleries linked to those prevalent in the arts, museology, and politics at the time. Many contemporary South African artists called attention to apartheid oppression and human rights abuses during the 1980s. After 1990, with these pressures alleviating, there was a stage of uncertainty as to the role, responsibility, and focus of visual art in a post-‘struggle’ context, however there was also an unprecedented upswing in interest and investment in it. On a practical level, the administration of the arts was being re-evaluated and contested by both independent and politically-aligned arts groups. Public art museums and sponsored art competitions and exhibitions made increasing efforts to be ‘representative’ of South Africans of all races, cultures, creeds, sexes and genders. The many conferences, committees, and conventions created during this transitional era focused on the creation of policies that would assist in nation-building; historical and cultural redress and regeneration; and the education and representation of previously disadvantaged groups. This coincided with a revolution in museological discourses internationally, from the theorization of a museum as a place of commemoration and conservation, to a forum for discussion and revision between both academic and non-academic communities. With the sharing of the process of constructing history and knowledge, came the challenging dynamics involved in the representation of identity and history. In all of these groups - the arts, museology, and South African politics - the predominant issue seemed to be a negotiation between the bid to open up control to more parties, and the reluctance of some parties to relinquish control. While the emphasis is on significant changes that were implemented in the transitional period, the study locates the changes at the Johannesburg Art Gallery, the South African National Gallery and the Durban Art Gallery within their historical, geographical, and socio-political context. Various artists working in these locations during this era are also discussed, as the changes in their status, and the progressions in their subject matter, materials, and concerns are interesting to examine more nuanced definitions of the ‘political’, probing the politics of identity, sexuality, gender, race, geography, and belief systems. Some artists also focused specifically on post-apartheid preoccupations with territory, trauma, conflict, memory and freedom. This kind of artwork was assiduously acquired during the early ‘90s by public art galleries, whose exhibitions and collecting focus and policies were undergoing considerable revision and redress. This thesis examines these changes in light of their socio-political contexts, as well as in light of shifting national and international imperatives and conceptions of museums and museum practice.
- Full Text:
- Authors: Cook, Shashi Chailey
- Date: 2009
- Subjects: South African National Gallery Exhibitions Durban Art Gallery Exhibitions Joahnnesburg Art Gallery Exhibitions Art -- South Africa -- Exhibitions Art, South African Exhibitions South Africa History Exhibitions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2399 , http://hdl.handle.net/10962/d1002195
- Description: This thesis centres on the debates informing the progress of three public art galleries in South Africa between 1990 and 1994. This was a period of great change in the country, spanning from the unbanning of left-wing political parties and Nelson Mandela’s release from prison, to the first democratic elections which resulted in his inauguration as President of South Africa. The study focuses specifically on the Johannesburg Art Gallery, the South African National Gallery, and the Durban Art Gallery, delineating the events and exhibitions held, the programmes initiated, and the artists represented by these galleries during this post-apartheid/pre-democracy phase of the country’s history. The debates relevant to these galleries linked to those prevalent in the arts, museology, and politics at the time. Many contemporary South African artists called attention to apartheid oppression and human rights abuses during the 1980s. After 1990, with these pressures alleviating, there was a stage of uncertainty as to the role, responsibility, and focus of visual art in a post-‘struggle’ context, however there was also an unprecedented upswing in interest and investment in it. On a practical level, the administration of the arts was being re-evaluated and contested by both independent and politically-aligned arts groups. Public art museums and sponsored art competitions and exhibitions made increasing efforts to be ‘representative’ of South Africans of all races, cultures, creeds, sexes and genders. The many conferences, committees, and conventions created during this transitional era focused on the creation of policies that would assist in nation-building; historical and cultural redress and regeneration; and the education and representation of previously disadvantaged groups. This coincided with a revolution in museological discourses internationally, from the theorization of a museum as a place of commemoration and conservation, to a forum for discussion and revision between both academic and non-academic communities. With the sharing of the process of constructing history and knowledge, came the challenging dynamics involved in the representation of identity and history. In all of these groups - the arts, museology, and South African politics - the predominant issue seemed to be a negotiation between the bid to open up control to more parties, and the reluctance of some parties to relinquish control. While the emphasis is on significant changes that were implemented in the transitional period, the study locates the changes at the Johannesburg Art Gallery, the South African National Gallery and the Durban Art Gallery within their historical, geographical, and socio-political context. Various artists working in these locations during this era are also discussed, as the changes in their status, and the progressions in their subject matter, materials, and concerns are interesting to examine more nuanced definitions of the ‘political’, probing the politics of identity, sexuality, gender, race, geography, and belief systems. Some artists also focused specifically on post-apartheid preoccupations with territory, trauma, conflict, memory and freedom. This kind of artwork was assiduously acquired during the early ‘90s by public art galleries, whose exhibitions and collecting focus and policies were undergoing considerable revision and redress. This thesis examines these changes in light of their socio-political contexts, as well as in light of shifting national and international imperatives and conceptions of museums and museum practice.
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Regulating franchise operations in South Africa : a study of the existing legal framework with suggestions for reform.
- Authors: Woker, Tanya Ann
- Date: 2009
- Subjects: Franchise Association of Southern Africa , Franchises (Retail trade) -- Law and legislation -- South Africa , South Africa. Dept. of Trade and Industry , Common law -- South Africa , Commercial law -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3721 , http://hdl.handle.net/10962/d1015719
- Description: This thesis analyses the existing legal framework that applies to franchising in South Africa today. The study begins with an examination of the history and nature of the franchise contract, focusing particularly on the nature of the franchise relationship. This study is undertaken in order to substantiate the argument that franchising is a unique method of doing business. There is a need therefore to recognise that the franchise contract is a special contract in its own right, just like contracts of sale, lease, insurance and suretyship. The study then goes on to examine the problems which are experienced in the sector, as well as the law which must provide solutions to these problems. The research will show that in a modern commercial world the existing legal framework, especially the common law, cannot adequately deal with many of these problems. The complex relationship between franchising and competition law is also explored. A common thread that emerges from franchise disputes is the lack of protection afforded to the interests of franchisees. Franchisees tend to be at the mercy of economically stronger franchisors, hence the belief that there is a need for a stronger regulatory framework. The study then shifts to proposals for reform. In 2000 the Department of Trade and Industry (DTI) established the Franchise Steering Committee in conjunction with the Franchise Association of South Africa (FASA) to review the regulatory environment. This Committee drafted franchise legislation which aimed to bring the regulation of the sector under the control of the DTI. This legislation has not been implemented and the DTI has changed its strategy. Instead of dealing with franchising independently, franchising will fall within the scope of consumer protection legislation. Both the consumer protection legislation and the legislation proposed by the Franchise Steering Committee are thoroughly examined and explained. Shortcomings in the proposals are highlighted and an alternative approach is recommended. It is proposed that franchise-specific legislation should be introduced but that this legislation should establish a system of co-regulation between the government and the franchise sector.
- Full Text:
- Authors: Woker, Tanya Ann
- Date: 2009
- Subjects: Franchise Association of Southern Africa , Franchises (Retail trade) -- Law and legislation -- South Africa , South Africa. Dept. of Trade and Industry , Common law -- South Africa , Commercial law -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3721 , http://hdl.handle.net/10962/d1015719
- Description: This thesis analyses the existing legal framework that applies to franchising in South Africa today. The study begins with an examination of the history and nature of the franchise contract, focusing particularly on the nature of the franchise relationship. This study is undertaken in order to substantiate the argument that franchising is a unique method of doing business. There is a need therefore to recognise that the franchise contract is a special contract in its own right, just like contracts of sale, lease, insurance and suretyship. The study then goes on to examine the problems which are experienced in the sector, as well as the law which must provide solutions to these problems. The research will show that in a modern commercial world the existing legal framework, especially the common law, cannot adequately deal with many of these problems. The complex relationship between franchising and competition law is also explored. A common thread that emerges from franchise disputes is the lack of protection afforded to the interests of franchisees. Franchisees tend to be at the mercy of economically stronger franchisors, hence the belief that there is a need for a stronger regulatory framework. The study then shifts to proposals for reform. In 2000 the Department of Trade and Industry (DTI) established the Franchise Steering Committee in conjunction with the Franchise Association of South Africa (FASA) to review the regulatory environment. This Committee drafted franchise legislation which aimed to bring the regulation of the sector under the control of the DTI. This legislation has not been implemented and the DTI has changed its strategy. Instead of dealing with franchising independently, franchising will fall within the scope of consumer protection legislation. Both the consumer protection legislation and the legislation proposed by the Franchise Steering Committee are thoroughly examined and explained. Shortcomings in the proposals are highlighted and an alternative approach is recommended. It is proposed that franchise-specific legislation should be introduced but that this legislation should establish a system of co-regulation between the government and the franchise sector.
- Full Text:
Repetitive symbolic play as a therapeutic process
- Authors: Campbell, Megan
- Date: 2009
- Subjects: Play therapy Symbolic play Child psychology Developmental psychology
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2944 , http://hdl.handle.net/10962/d1002453
- Description: Child centred play therapy theory explains that the facilitative environment of the relationship between child and play therapist allows the child the opportunity to confront emotional pain imbedded in lived, relational experiences, and in so doing process and gain mastery over it. However very little research exists into how the child, through his use of repetitive, symbolic play, as a therapeutic process, achieves this resolution. This research project aims to address this gap in research by exploring and describing repetitive symbolic play as a therapeutic process within child centred play therapy that facilitates change in the child‟s sense of self, assisting him towards healthy adjustment. The research project uses a young boys‟ therapeutic process as a case study, employing a qualitative research design that draws from interpretative research. Fourteen repetitive play sequence themes were analysed within the context of the case formulation and follow-up feedback meetings that took place throughout the therapy process. Using a hermeneutic enquiry the researcher illustrates how the child‟s sense of self, dependent on his perceptions of his external environment, became far more congruent, as evident through his behaviour, when his environment, first in play therapy, then at home and at school became more consistent, supportive and nurturing. Within this facilitative environment the researcher then describes how the child used repetitive symbolic play to address and process emotional issues relating to earlier experiences within his external environment. Hermeneutic analysis suggests that the child‟s use of repetitive symbolic play within the facilitative relationship between him and his therapist became a therapeutic process in and of itself that contributed towards self-directed healing, and change within his sense of self, that promoted healthier adjustment within his environment.
- Full Text:
- Authors: Campbell, Megan
- Date: 2009
- Subjects: Play therapy Symbolic play Child psychology Developmental psychology
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2944 , http://hdl.handle.net/10962/d1002453
- Description: Child centred play therapy theory explains that the facilitative environment of the relationship between child and play therapist allows the child the opportunity to confront emotional pain imbedded in lived, relational experiences, and in so doing process and gain mastery over it. However very little research exists into how the child, through his use of repetitive, symbolic play, as a therapeutic process, achieves this resolution. This research project aims to address this gap in research by exploring and describing repetitive symbolic play as a therapeutic process within child centred play therapy that facilitates change in the child‟s sense of self, assisting him towards healthy adjustment. The research project uses a young boys‟ therapeutic process as a case study, employing a qualitative research design that draws from interpretative research. Fourteen repetitive play sequence themes were analysed within the context of the case formulation and follow-up feedback meetings that took place throughout the therapy process. Using a hermeneutic enquiry the researcher illustrates how the child‟s sense of self, dependent on his perceptions of his external environment, became far more congruent, as evident through his behaviour, when his environment, first in play therapy, then at home and at school became more consistent, supportive and nurturing. Within this facilitative environment the researcher then describes how the child used repetitive symbolic play to address and process emotional issues relating to earlier experiences within his external environment. Hermeneutic analysis suggests that the child‟s use of repetitive symbolic play within the facilitative relationship between him and his therapist became a therapeutic process in and of itself that contributed towards self-directed healing, and change within his sense of self, that promoted healthier adjustment within his environment.
- Full Text:
Restoration of degraded subtropical thickets in the Baviaanskloof Megareserve, South Africa: the role of carbon stocks and Portulacaria afra survivorship
- Authors: Powell, Michael John
- Date: 2009
- Subjects: Portulacaria afra -- South Africa -- Eastern Cape , Portulacaceae -- South Africa -- Eastern Cape , Biodiversity conservation -- South Africa -- Eastern Cape , Plant conservation -- South Africa -- Eastern Cape , Shrubs -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Baviaanskloof (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4764 , http://hdl.handle.net/10962/d1007164 , Portulacaria afra -- South Africa -- Eastern Cape , Portulacaceae -- South Africa -- Eastern Cape , Biodiversity conservation -- South Africa -- Eastern Cape , Plant conservation -- South Africa -- Eastern Cape , Shrubs -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Baviaanskloof (South Africa)
- Description: The semi-arid forms of subtropical thicket in the Eastern and Western Cape have been heavily degraded through unsustainable pastoralism over the last century or more. The degraded areas exhibit a significant loss of above-ground and belowground carbon stocks, and consequently provide an opportunity for restoration through the formal and informal carbon markets. A prerequisite for the attainment of carbon credits is to ensure sound carbon stock baselines prior to effecting restoration. I report on the carbon stocks (including sub-pools) for a number of intact subtropical thicket types, as well as the differentials between the intact and degraded states (including the sub-pools). Total carbon stocks (TCS in t C ha⁻¹) for intact vegetation (to a soil depth 0–25 cm), ranged from 87.73±6.51 to 70.64±17.24. For degraded vegetation (including old lands), TCS (t C ha⁻¹) ranged from 34.05±3.61 to 21.03±2.70. For all vegetation types, the differentials in TCS along the degradation gradient (0–25 cm) are highly significant and strengthen the possibility for carbon credit financing to catalyse the restoration of the degraded semi-arid subtropical thickets. This study has shown a mean loss of 57.23 t C ha⁻¹ in Baviaanskloof spekboom thickets, when measured to a soil depth of 25 cm. Portulacaria afra is a key species within the semi-arid subtropical thickets, being a canopy dominant and a driver of soil nutrient status, but has been largely lost from the degraded landscapes. Degraded semi-arid subtropical thicket vegetation lacks regeneration via seedling recruitment; restoration therefore requires the manual replanting of P. afra using cut truncheons. Survivorship trials were undertaken infield in 2005 to establish restoration protocols for P. afra, with survivorship being recorded in 2006 and 2008. Overall survivorship for all treatments was found to be 43.2±2.8% in 2006, dropping to 35.8±2.7% in 2008. Planting posture (flat or upright) showed the most significant results of all the factors tested in 2006 and 2008. Micro-damming also influenced survivorship in that micro-damming was associated with marginally higher survivorship (47.4 ±2.0% with damming vs. 39.1±1.5% without damming in 2006, and 39.3±1.9% vs. 32.3±1.5% in 2008). Higher planting density only showed a significant positive impact on survivorship in 2008. Neither stem diameter nor clumping significantly affected degree of survival. A key finding in the study has been the non-static nature of P. afra truncheon survivorship, even after being well established (three years since planting). The results from the study will guide the restoration protocols for the restoration of degraded subtropical thickets, where P. afra requires replanting.
- Full Text:
- Authors: Powell, Michael John
- Date: 2009
- Subjects: Portulacaria afra -- South Africa -- Eastern Cape , Portulacaceae -- South Africa -- Eastern Cape , Biodiversity conservation -- South Africa -- Eastern Cape , Plant conservation -- South Africa -- Eastern Cape , Shrubs -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Baviaanskloof (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4764 , http://hdl.handle.net/10962/d1007164 , Portulacaria afra -- South Africa -- Eastern Cape , Portulacaceae -- South Africa -- Eastern Cape , Biodiversity conservation -- South Africa -- Eastern Cape , Plant conservation -- South Africa -- Eastern Cape , Shrubs -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Baviaanskloof (South Africa)
- Description: The semi-arid forms of subtropical thicket in the Eastern and Western Cape have been heavily degraded through unsustainable pastoralism over the last century or more. The degraded areas exhibit a significant loss of above-ground and belowground carbon stocks, and consequently provide an opportunity for restoration through the formal and informal carbon markets. A prerequisite for the attainment of carbon credits is to ensure sound carbon stock baselines prior to effecting restoration. I report on the carbon stocks (including sub-pools) for a number of intact subtropical thicket types, as well as the differentials between the intact and degraded states (including the sub-pools). Total carbon stocks (TCS in t C ha⁻¹) for intact vegetation (to a soil depth 0–25 cm), ranged from 87.73±6.51 to 70.64±17.24. For degraded vegetation (including old lands), TCS (t C ha⁻¹) ranged from 34.05±3.61 to 21.03±2.70. For all vegetation types, the differentials in TCS along the degradation gradient (0–25 cm) are highly significant and strengthen the possibility for carbon credit financing to catalyse the restoration of the degraded semi-arid subtropical thickets. This study has shown a mean loss of 57.23 t C ha⁻¹ in Baviaanskloof spekboom thickets, when measured to a soil depth of 25 cm. Portulacaria afra is a key species within the semi-arid subtropical thickets, being a canopy dominant and a driver of soil nutrient status, but has been largely lost from the degraded landscapes. Degraded semi-arid subtropical thicket vegetation lacks regeneration via seedling recruitment; restoration therefore requires the manual replanting of P. afra using cut truncheons. Survivorship trials were undertaken infield in 2005 to establish restoration protocols for P. afra, with survivorship being recorded in 2006 and 2008. Overall survivorship for all treatments was found to be 43.2±2.8% in 2006, dropping to 35.8±2.7% in 2008. Planting posture (flat or upright) showed the most significant results of all the factors tested in 2006 and 2008. Micro-damming also influenced survivorship in that micro-damming was associated with marginally higher survivorship (47.4 ±2.0% with damming vs. 39.1±1.5% without damming in 2006, and 39.3±1.9% vs. 32.3±1.5% in 2008). Higher planting density only showed a significant positive impact on survivorship in 2008. Neither stem diameter nor clumping significantly affected degree of survival. A key finding in the study has been the non-static nature of P. afra truncheon survivorship, even after being well established (three years since planting). The results from the study will guide the restoration protocols for the restoration of degraded subtropical thickets, where P. afra requires replanting.
- Full Text:
Restructuring of the Port Elizabeth Hospital Complex: a perspective from the planned change management approach
- Authors: Qwesha, Babalwa
- Date: 2009
- Subjects: Hospitals -- Administration -- South Africa -- Port Elizabeth Organizational change -- Management -- South Africa Case studies
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:762 , http://hdl.handle.net/10962/d1003883
- Description: The research objectives which underpin this study were threefold. Firstly was to analyze the Port Elizabeth Hospital Complex (PEHC) restructuring process from a planned changed management perspective in particular the three stage model of Lewin (1951) which include unfreezing the current equilibrium, moving to a new position and refreezing in the new position. Secondly was to analyze how unforeseen circumstances were dealt with. Thirdly was to analyse the setting of objectives and measurements of targets to monitor progress. The study is based on the restructuring that took place in the PEHC which was called “Rationalization”. The research indicates that the development and implementation of the rationalization cannot be understood from the perspective of the three stage model of Lewin (1951). The conclusion was based on the manager’s perceptions of their analysis of the restructuring in the light of the theory of the three stage model of Lewin (1951). The study has shown that: · Rationalisation began by gathering information on the shortcomings of the structure of the three hospitals, but did not understand the degree of readiness to change. · The timescales for achieving rationalization were not clearly defined. · It was driven from the top with clear objectives and no timescales. · There was no structure that prepared the employees to go through the process of rationalisation. · There was lack of capacity of middle managers to respond to the workers in an encouraging way. · Rationalisation sub-committees had limited time to meet with employees at the sectional level. · External stakeholder involvement was not mobilized to its full potential. · Rationalisation was not an open process that involved both formal and informal employees. · Budget constraints and staff shortages were not informed by the restructuring needs. · Workers did not feel secure about the current and future work practises. · There was no feeling that the change will be beneficial to their wellbeing and to the organisation’s goals and mission · There was no monitoring and evaluation put in place to track progress. · There was centralisation of even the most basic administrative functions. The study seems to imply that the restructuring in the PEHC bears no resemblance to the Lewin (1951) planned change model and therefore cannot be understood from the perspective of this model. Given the initiative to rationalize, the PEHC management can learn from the model of Lewin (1951) planned change.
- Full Text:
- Authors: Qwesha, Babalwa
- Date: 2009
- Subjects: Hospitals -- Administration -- South Africa -- Port Elizabeth Organizational change -- Management -- South Africa Case studies
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:762 , http://hdl.handle.net/10962/d1003883
- Description: The research objectives which underpin this study were threefold. Firstly was to analyze the Port Elizabeth Hospital Complex (PEHC) restructuring process from a planned changed management perspective in particular the three stage model of Lewin (1951) which include unfreezing the current equilibrium, moving to a new position and refreezing in the new position. Secondly was to analyze how unforeseen circumstances were dealt with. Thirdly was to analyse the setting of objectives and measurements of targets to monitor progress. The study is based on the restructuring that took place in the PEHC which was called “Rationalization”. The research indicates that the development and implementation of the rationalization cannot be understood from the perspective of the three stage model of Lewin (1951). The conclusion was based on the manager’s perceptions of their analysis of the restructuring in the light of the theory of the three stage model of Lewin (1951). The study has shown that: · Rationalisation began by gathering information on the shortcomings of the structure of the three hospitals, but did not understand the degree of readiness to change. · The timescales for achieving rationalization were not clearly defined. · It was driven from the top with clear objectives and no timescales. · There was no structure that prepared the employees to go through the process of rationalisation. · There was lack of capacity of middle managers to respond to the workers in an encouraging way. · Rationalisation sub-committees had limited time to meet with employees at the sectional level. · External stakeholder involvement was not mobilized to its full potential. · Rationalisation was not an open process that involved both formal and informal employees. · Budget constraints and staff shortages were not informed by the restructuring needs. · Workers did not feel secure about the current and future work practises. · There was no feeling that the change will be beneficial to their wellbeing and to the organisation’s goals and mission · There was no monitoring and evaluation put in place to track progress. · There was centralisation of even the most basic administrative functions. The study seems to imply that the restructuring in the PEHC bears no resemblance to the Lewin (1951) planned change model and therefore cannot be understood from the perspective of this model. Given the initiative to rationalize, the PEHC management can learn from the model of Lewin (1951) planned change.
- Full Text:
Rights, duties and remedies under the United Nations Convention on Contracts for the International Sale of Goods: an investigation into the CISG's compatibility with South African law
- Authors: Oosthuizen, Beverley-Claire
- Date: 2009
- Subjects: United Nations Convention on Contracts for the International Sale of Goods (1980) , Sales -- South Africa , Commercial law -- South Africa , South Africa -- Law and legislation
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3691 , http://hdl.handle.net/10962/d1003206 , United Nations Convention on Contracts for the International Sale of Goods (1980) , Sales -- South Africa , Commercial law -- South Africa , South Africa -- Law and legislation
- Description: This thesis analyses the compatibility of the United Nations Convention on Contracts for the International Sale of Goods (CISG) with the South African law of sale. An initial examination of the historical development of the CISG reveals its ambitions of becoming the primary source of law governing international contracts of sale. The goal of this research is to determine whether South Africa should ratify the CISG. The CISG has been ratified by most of the leading trading States in the world. In order to gain a better understanding of the advantages and disadvantages of ratification, a comparative study has been undertaken. The stance taken toward the CISG by the United Kingdom and Germany has been examined. The United Kingdom has staunchly avoided ratifying the CISG, despite having agreed thereto a number of years ago. Germany however has taken a different approach and has welcomed the CISG. The experiences of these foreign States serve as a useful guide when assessing the specific challenges that exist in South Africa concerning the adoption of the CISG. The most important aspect of this study is the direct comparison between the legal provisions housed in the CISG and their counterparts under South African law. A careful investigation has been conducted into the rights, duties, and remedies under the CISG. This investigation is followed by an examination of the corresponding rights, duties, and remedies under the South African domestic law of sale. It is evident from these explorations that the rights and duties under the CISG strongly resemble those under South African law. The direct comparison revealed however that certain remedies found in the CISG do not have a counterpart under South African law. Despite this discrepancy, there are no legal principles in the CISG that are completely unknown in South African law. While certain remedies housed in the CISG cannot be found in an identical form under South African law, sufficiently similar legal principles can be found, which frequently lead to the same results as those under the CISG. This study is concluded with a recommendation concerning South Africa’s adoption of the CISG.
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- Authors: Oosthuizen, Beverley-Claire
- Date: 2009
- Subjects: United Nations Convention on Contracts for the International Sale of Goods (1980) , Sales -- South Africa , Commercial law -- South Africa , South Africa -- Law and legislation
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3691 , http://hdl.handle.net/10962/d1003206 , United Nations Convention on Contracts for the International Sale of Goods (1980) , Sales -- South Africa , Commercial law -- South Africa , South Africa -- Law and legislation
- Description: This thesis analyses the compatibility of the United Nations Convention on Contracts for the International Sale of Goods (CISG) with the South African law of sale. An initial examination of the historical development of the CISG reveals its ambitions of becoming the primary source of law governing international contracts of sale. The goal of this research is to determine whether South Africa should ratify the CISG. The CISG has been ratified by most of the leading trading States in the world. In order to gain a better understanding of the advantages and disadvantages of ratification, a comparative study has been undertaken. The stance taken toward the CISG by the United Kingdom and Germany has been examined. The United Kingdom has staunchly avoided ratifying the CISG, despite having agreed thereto a number of years ago. Germany however has taken a different approach and has welcomed the CISG. The experiences of these foreign States serve as a useful guide when assessing the specific challenges that exist in South Africa concerning the adoption of the CISG. The most important aspect of this study is the direct comparison between the legal provisions housed in the CISG and their counterparts under South African law. A careful investigation has been conducted into the rights, duties, and remedies under the CISG. This investigation is followed by an examination of the corresponding rights, duties, and remedies under the South African domestic law of sale. It is evident from these explorations that the rights and duties under the CISG strongly resemble those under South African law. The direct comparison revealed however that certain remedies found in the CISG do not have a counterpart under South African law. Despite this discrepancy, there are no legal principles in the CISG that are completely unknown in South African law. While certain remedies housed in the CISG cannot be found in an identical form under South African law, sufficiently similar legal principles can be found, which frequently lead to the same results as those under the CISG. This study is concluded with a recommendation concerning South Africa’s adoption of the CISG.
- Full Text: