Solid-phase extraction based sample preparation for the determination of drug and organic pollutant residue
- Authors: Pule, Bellah Oreeditse
- Date: 2011 , 2011-02-08
- Subjects: Food contamination , Drugs -- Analysis , Pharmaceutical chemistry , Extraction (Chemistry) , Sorbents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4406 , http://hdl.handle.net/10962/d1006711 , Food contamination , Drugs -- Analysis , Pharmaceutical chemistry , Extraction (Chemistry) , Sorbents
- Description: This thesis presents solid phase extraction (SPE) methodologies based on mixed-mode polymeric sorbents; a mixed mode strong anion exchanger (Agilent SampliQ SAX) and a mixed mode strong cation exchanger (Agilent SampliQ SCX). Furthermore, dispersive-SPE based on a quick, easy, cheap, effective, rugged and safe (QuEChERS) method was assessed for applicability in the determination of drug residues. The mixed-mode polymeric sorbents were evaluated for the simultaneous fractionation of drugs that exhibit diverse polarities with acidic, basic and neutral functionalities in biological matrices (plasma and urine). The polymeric skeleton of these sorbents entails an exchanger group and therefore provides two retention mechanisms, strong cation or anion exchange retention mechanisms with hydrophobic interactions. It was demonstrated that with a sequential elution protocol for sample clean-up analytes were fractionated into acidic, basic and neutral classes. The SAX was employed for analysis of ketoprofen, naproxen (acidic drugs), nortriptyline (basic) and secobarbital (neutral) from urine sample. The SCX was used for fractionating phenobarbital, p-toluamide (acidic), amphetamine, m-toluidine (basic) and acetaminophen (neutral drug) from plasma sample. QuEChERS method was employed for quantitative determination of 16 polycyclic aromatic hydrocarbons (PAHs) from fish fillets and soil; 9 sulfonamides (SAs) from chicken muscles and acrylamide (AA) in cooking oil. The analyte recoveries ranged from 79.6 - 109% with RSDs ranging from 0.06 - 1.9% at three different fortification levels. Good linearity (r2 > 0.9990) was attained for most analytes. The limits of detection and quantification ranged from 0.03 - 0.84 μg/ml and 0.81 - 1.89 μg/ml respectively for analytes in biological samples. LODs and LOQs for analytes in food and environmental samples ranged from 0.02 to 0.39 and 0.25 to 1.30 ng/g respectively.
- Full Text:
- Authors: Pule, Bellah Oreeditse
- Date: 2011 , 2011-02-08
- Subjects: Food contamination , Drugs -- Analysis , Pharmaceutical chemistry , Extraction (Chemistry) , Sorbents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4406 , http://hdl.handle.net/10962/d1006711 , Food contamination , Drugs -- Analysis , Pharmaceutical chemistry , Extraction (Chemistry) , Sorbents
- Description: This thesis presents solid phase extraction (SPE) methodologies based on mixed-mode polymeric sorbents; a mixed mode strong anion exchanger (Agilent SampliQ SAX) and a mixed mode strong cation exchanger (Agilent SampliQ SCX). Furthermore, dispersive-SPE based on a quick, easy, cheap, effective, rugged and safe (QuEChERS) method was assessed for applicability in the determination of drug residues. The mixed-mode polymeric sorbents were evaluated for the simultaneous fractionation of drugs that exhibit diverse polarities with acidic, basic and neutral functionalities in biological matrices (plasma and urine). The polymeric skeleton of these sorbents entails an exchanger group and therefore provides two retention mechanisms, strong cation or anion exchange retention mechanisms with hydrophobic interactions. It was demonstrated that with a sequential elution protocol for sample clean-up analytes were fractionated into acidic, basic and neutral classes. The SAX was employed for analysis of ketoprofen, naproxen (acidic drugs), nortriptyline (basic) and secobarbital (neutral) from urine sample. The SCX was used for fractionating phenobarbital, p-toluamide (acidic), amphetamine, m-toluidine (basic) and acetaminophen (neutral drug) from plasma sample. QuEChERS method was employed for quantitative determination of 16 polycyclic aromatic hydrocarbons (PAHs) from fish fillets and soil; 9 sulfonamides (SAs) from chicken muscles and acrylamide (AA) in cooking oil. The analyte recoveries ranged from 79.6 - 109% with RSDs ranging from 0.06 - 1.9% at three different fortification levels. Good linearity (r2 > 0.9990) was attained for most analytes. The limits of detection and quantification ranged from 0.03 - 0.84 μg/ml and 0.81 - 1.89 μg/ml respectively for analytes in biological samples. LODs and LOQs for analytes in food and environmental samples ranged from 0.02 to 0.39 and 0.25 to 1.30 ng/g respectively.
- Full Text:
South African money market volatility, asymmetry and retail interest pass-through
- Authors: Fadiran, Gideon Oluwatobi
- Date: 2011
- Subjects: Money market -- South Africa Interest rates -- South Africa Monetary policy -- South Africa Econometric models Banks and banking -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:993 , http://hdl.handle.net/10962/d1002728
- Description: The purpose of this paper is to examine the interest rate transmission mechanism for South Africa as an emerging economy in a pre-repo and repo system. It explains how the money market rate is transmitted to the retail interest rates both in the long-run and short-run and tests the symmetric and asymmetric interest rate pass-through using the Scholnick (1996) ECM and the Wang and Lee (2009) ECM-EGARCH (1, 1)-M methodology. This permitted the examination of the impact of interest rate volatility, along with the leverage effect. An incomplete pass-through is found in the short-run. From the entire sample period, a symmetric adjustment is found in the deposit rate, which had upward rigidity adjustment, while an asymmetric adjustment is found in the lending rate, with a downward rigidity adjustment. All the adjustments supported the collusive pricing arrangements. According to the conditional variance estimation of the ECM-EGARCH (1, 1), negative volatility impact and leverage effect are present and influential only in the deposit interest rate adjustment process in South Africa.
- Full Text:
- Authors: Fadiran, Gideon Oluwatobi
- Date: 2011
- Subjects: Money market -- South Africa Interest rates -- South Africa Monetary policy -- South Africa Econometric models Banks and banking -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:993 , http://hdl.handle.net/10962/d1002728
- Description: The purpose of this paper is to examine the interest rate transmission mechanism for South Africa as an emerging economy in a pre-repo and repo system. It explains how the money market rate is transmitted to the retail interest rates both in the long-run and short-run and tests the symmetric and asymmetric interest rate pass-through using the Scholnick (1996) ECM and the Wang and Lee (2009) ECM-EGARCH (1, 1)-M methodology. This permitted the examination of the impact of interest rate volatility, along with the leverage effect. An incomplete pass-through is found in the short-run. From the entire sample period, a symmetric adjustment is found in the deposit rate, which had upward rigidity adjustment, while an asymmetric adjustment is found in the lending rate, with a downward rigidity adjustment. All the adjustments supported the collusive pricing arrangements. According to the conditional variance estimation of the ECM-EGARCH (1, 1), negative volatility impact and leverage effect are present and influential only in the deposit interest rate adjustment process in South Africa.
- Full Text:
SphereZyme (TM) technology for enhanced enzyme immobilisation application in biosensors
- Authors: Molawa, Letshego Gloria
- Date: 2011
- Subjects: Immobilized enzymes , Hydrolases , Hydrolysis , SphereZyme , Biosensors , Proteolytic enzymes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3989 , http://hdl.handle.net/10962/d1004048 , Immobilized enzymes , Hydrolases , Hydrolysis , SphereZyme , Biosensors , Proteolytic enzymes
- Description: Self-immobilisation enzyme technologies, such as SphereZyme™, suffer from the lack of applicability to hydrolyse large substrates. Solid support immobilisation is usually a method of choice, to produce a stable biocatalyst for large substrates hydrolysis in the industry. In order to investigate this limitation, a commercial protease called Alcalase® was chosen as a model enzyme due to its natural activity (hydrolysis of large substrates-proteins). Prior to immobilising through the SphereZyme™ technology, Alcalase® was partially purified through dialysis followed by CM Sepharose™ FF cation exchanger. Sample contaminants, such as salts and stabilisers can inhibit protein crosslinking by reacting with glutaraldehyde. Alcalase® was successfully separated into 3 proteases with the major peak correlating to a positive control run on native PAGE, indicating that it was likely subtilisin Carlsberg. A 16% alkaline protease activity for azo-casein hydrolysis was retained when 5% v/v PEI: 25% v/v glutaraldehyde solution was used as a crosslinking agent in Alcalase® SphereZyme™ production. An increase in activity was also observed for monomeric substrates (PNPA) where the highest was 55%. The highest % activities maintained when 0.33 M EDA: 25% v/v glutaraldehyde solution was initially used as crosslinking agent were 4.5% and 1.6% for monomeric and polymeric substrates, respectively. PEI is a hydrophilic branched polymer with an abundance of amine groups compared to EDA. A comparison study of immobilisation efficiencies of SphereZyme™, Eupergit® and Dendrispheres was also performed for large substrate biocatalysis. The two latter technologies are solid-support immobilisation methods. Dendrispheres reached its maximum loading capacity in the first 5 minute of the one hour binding time. Twenty minutes was chosen as a maximum binding time since there was constant protein maintained on the solid support and no enzyme loss was observed during the 1 hour binding time. PEI at pH 11.5, its native pH, gave the highest immobilisation yield and specific activity over the PEI pH range of 11.5 to 7. SphereZyme™ had the highest ratio for azocasein hydrolysis followed by Dendrispheres and Eupergit®. The SphereZyme™ was also shown to be applicable to biosensors for phenol detection. Different modifications of glassy carbon electrode (GCE) were evaluated as a benchmark for the fabrication of SphereZyme™ modified phenol biosensor. GCE modified with laccase SphereZyme™ entrapped in cellulose membrane was the best modification due to the broad catechol range (<0.950 mM), high correlation coefficient (R2, 0.995) and relative high sensitivity factor (0.305 μA.mM-1). This type of biosensor was also shown to be electroactive at pH 7.0 for which its control, free laccase, lacked electroactivity. From the catalytic constants calculated, GCE modified with laccase SphereZyme™ entrapped in cellulose membrane also gave the highest effectiveness factor (Imax/Km app) of 1.84 μA.mM-1. The modified GCE with Alcalase® SphereZyme™ was relatively more sensitive than GCE modified with free Alcalase®.
- Full Text:
- Authors: Molawa, Letshego Gloria
- Date: 2011
- Subjects: Immobilized enzymes , Hydrolases , Hydrolysis , SphereZyme , Biosensors , Proteolytic enzymes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3989 , http://hdl.handle.net/10962/d1004048 , Immobilized enzymes , Hydrolases , Hydrolysis , SphereZyme , Biosensors , Proteolytic enzymes
- Description: Self-immobilisation enzyme technologies, such as SphereZyme™, suffer from the lack of applicability to hydrolyse large substrates. Solid support immobilisation is usually a method of choice, to produce a stable biocatalyst for large substrates hydrolysis in the industry. In order to investigate this limitation, a commercial protease called Alcalase® was chosen as a model enzyme due to its natural activity (hydrolysis of large substrates-proteins). Prior to immobilising through the SphereZyme™ technology, Alcalase® was partially purified through dialysis followed by CM Sepharose™ FF cation exchanger. Sample contaminants, such as salts and stabilisers can inhibit protein crosslinking by reacting with glutaraldehyde. Alcalase® was successfully separated into 3 proteases with the major peak correlating to a positive control run on native PAGE, indicating that it was likely subtilisin Carlsberg. A 16% alkaline protease activity for azo-casein hydrolysis was retained when 5% v/v PEI: 25% v/v glutaraldehyde solution was used as a crosslinking agent in Alcalase® SphereZyme™ production. An increase in activity was also observed for monomeric substrates (PNPA) where the highest was 55%. The highest % activities maintained when 0.33 M EDA: 25% v/v glutaraldehyde solution was initially used as crosslinking agent were 4.5% and 1.6% for monomeric and polymeric substrates, respectively. PEI is a hydrophilic branched polymer with an abundance of amine groups compared to EDA. A comparison study of immobilisation efficiencies of SphereZyme™, Eupergit® and Dendrispheres was also performed for large substrate biocatalysis. The two latter technologies are solid-support immobilisation methods. Dendrispheres reached its maximum loading capacity in the first 5 minute of the one hour binding time. Twenty minutes was chosen as a maximum binding time since there was constant protein maintained on the solid support and no enzyme loss was observed during the 1 hour binding time. PEI at pH 11.5, its native pH, gave the highest immobilisation yield and specific activity over the PEI pH range of 11.5 to 7. SphereZyme™ had the highest ratio for azocasein hydrolysis followed by Dendrispheres and Eupergit®. The SphereZyme™ was also shown to be applicable to biosensors for phenol detection. Different modifications of glassy carbon electrode (GCE) were evaluated as a benchmark for the fabrication of SphereZyme™ modified phenol biosensor. GCE modified with laccase SphereZyme™ entrapped in cellulose membrane was the best modification due to the broad catechol range (<0.950 mM), high correlation coefficient (R2, 0.995) and relative high sensitivity factor (0.305 μA.mM-1). This type of biosensor was also shown to be electroactive at pH 7.0 for which its control, free laccase, lacked electroactivity. From the catalytic constants calculated, GCE modified with laccase SphereZyme™ entrapped in cellulose membrane also gave the highest effectiveness factor (Imax/Km app) of 1.84 μA.mM-1. The modified GCE with Alcalase® SphereZyme™ was relatively more sensitive than GCE modified with free Alcalase®.
- Full Text:
Staged authenticities an exploration of the representations of AmaXhosa culture within the main programme of the National Arts Festival, 2009
- Reeve, Zoë Rose Louise Patricia
- Authors: Reeve, Zoë Rose Louise Patricia
- Date: 2011
- Subjects: Standard Bank National Arts Festival Performing arts festivals -- South Africa -- Grahamstown Xhosa (African people) -- Music -- Social aspects Performing arts festivals -- Social aspects -- South Africa -- Grahamstown Cultural property -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2146 , http://hdl.handle.net/10962/d1002378
- Description: This thesis investigates the presentation of AmaXhosa traditional dancing and music on the stages of the National Arts Festival (NAF), Main Programme, of South Africa in 2009. Four productions featuring AmaXhosa traditional dancing and music, as well as a fine art exhibition, are analysed to determine how the AmaXhosa culture is being portrayed, what is considered authentic and how these productions may affect the memory of the AmaXhosa nation. In an attempt to understand the position of these productions within the NAF the South African cultural context as well as the NAF is examined. The post-apartheid, post-rainbow nation, South African cultural context is discussed and how the NAF could contribute towards creating a more unified South African identity. Incorporated and inscribed memory categories are related to how one could determine authenticity in traditional indigenous productions. A cautionary note on incorporated memory is linked to efficacy, while a loss of incorporated memory within the AmaXhosa society may result in ritual acts being orientated towards entertainment. If the private culture is consistently displayed in the public realm then it is inevitable that the ways in which the AmaXhosa recollect their history will be altered. The contribution of the transitional spaces of theatres and proscenium arch stages to the choreography and incorporated memory of the performers relates to the collective recollection of the AmaXhosa. Bearing this in mind, this thesis suggests that the NAF is playing a dual role in the evolution of the AmaXhosa. It is both positively contributing to the economic upliftment of a sector of the population and exposing people to this rich and multilayered culture. However, it is also impacting the efficacy of the private culture and fracturing the traditional knowledge of the AmaXhosa by assisting in the inscription of their performance forms. , This thesis consists of three parts (1 pdf document and two video mp4 files)
- Full Text:
- Authors: Reeve, Zoë Rose Louise Patricia
- Date: 2011
- Subjects: Standard Bank National Arts Festival Performing arts festivals -- South Africa -- Grahamstown Xhosa (African people) -- Music -- Social aspects Performing arts festivals -- Social aspects -- South Africa -- Grahamstown Cultural property -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2146 , http://hdl.handle.net/10962/d1002378
- Description: This thesis investigates the presentation of AmaXhosa traditional dancing and music on the stages of the National Arts Festival (NAF), Main Programme, of South Africa in 2009. Four productions featuring AmaXhosa traditional dancing and music, as well as a fine art exhibition, are analysed to determine how the AmaXhosa culture is being portrayed, what is considered authentic and how these productions may affect the memory of the AmaXhosa nation. In an attempt to understand the position of these productions within the NAF the South African cultural context as well as the NAF is examined. The post-apartheid, post-rainbow nation, South African cultural context is discussed and how the NAF could contribute towards creating a more unified South African identity. Incorporated and inscribed memory categories are related to how one could determine authenticity in traditional indigenous productions. A cautionary note on incorporated memory is linked to efficacy, while a loss of incorporated memory within the AmaXhosa society may result in ritual acts being orientated towards entertainment. If the private culture is consistently displayed in the public realm then it is inevitable that the ways in which the AmaXhosa recollect their history will be altered. The contribution of the transitional spaces of theatres and proscenium arch stages to the choreography and incorporated memory of the performers relates to the collective recollection of the AmaXhosa. Bearing this in mind, this thesis suggests that the NAF is playing a dual role in the evolution of the AmaXhosa. It is both positively contributing to the economic upliftment of a sector of the population and exposing people to this rich and multilayered culture. However, it is also impacting the efficacy of the private culture and fracturing the traditional knowledge of the AmaXhosa by assisting in the inscription of their performance forms. , This thesis consists of three parts (1 pdf document and two video mp4 files)
- Full Text:
Stewardship as an educational process of social learning and change: two case studies conducted in the Western Cape
- Authors: Walker, Clara Isabella
- Date: 2011
- Subjects: Environmental education -- South Africa -- Western Cape Conservation of natural resources -- South Africa -- Western Cape Natural resources -- South Africa -- Western Cape -- Management Social learning -- South Africa -- Western Cape Sustainable development -- South Africa -- Western Cape Cape Nature Stewardship Programme (South Africa) Biodiversity Stewardship Programme (South Africa)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1772 , http://hdl.handle.net/10962/d1003657
- Description: Stewardship in South Africa, as it is being implemented within the framework of the Biodiversity Stewardship Programme (BSP), is an attempt by conservation agencies to engage landowners in the voluntary securing of parcels of biodiverse land, through signing a contract for a certain time period, not to develop the landscape in ways that will impact negatively on the biodiversity of the area in question. The focus of this study is the relationship between biodiversity stewardship and social learning, as I hope to ascertain how stewardship practices are helping to resolve the current problems of biodiversity loss in the Western Cape. The overall aim of this research is to gain an understanding of how, in its capacity as a conservation education process, the Cape Nature Stewardship Programme can foster social learning amongst the landowners involved in its implementation, by leading them to a better understanding of their environmental responsibilities. Data was generated through the use of interviews and informal discussions with participants together with document analysis, such as brochures, pamphlets and presentations. My approach to the analysis of my data was two-phased. In the first phase, I analysed the data generated from the interview process and from reviewing the documents the stewardship officials supplied me with. The second phase involved looking into the results of the two case studies, and formulating analytical statements which were then used to review the case evidence within a social learning perspective, derived from Wals (2007). In constructing an analytical framework for the interpretation of my data, I drew heavily on Wals' (2007) notion of social learning occurring in sequential activities. I used this insight as a lens through which to trace the educational effects of the implementation of the CNSP in the two case study areas.The research highlighted evidence that Stewardship initiatives should be based on the foundation of social learning and invest time and effort in building an environmental knowledge capital amongst the landowners involved. By equipping them with these necessary conservation skills, one creates a 'community of practice' where those individuals adopt a sustainability habitus contributing towards a change and environmental understanding and practises in field.
- Full Text:
- Authors: Walker, Clara Isabella
- Date: 2011
- Subjects: Environmental education -- South Africa -- Western Cape Conservation of natural resources -- South Africa -- Western Cape Natural resources -- South Africa -- Western Cape -- Management Social learning -- South Africa -- Western Cape Sustainable development -- South Africa -- Western Cape Cape Nature Stewardship Programme (South Africa) Biodiversity Stewardship Programme (South Africa)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1772 , http://hdl.handle.net/10962/d1003657
- Description: Stewardship in South Africa, as it is being implemented within the framework of the Biodiversity Stewardship Programme (BSP), is an attempt by conservation agencies to engage landowners in the voluntary securing of parcels of biodiverse land, through signing a contract for a certain time period, not to develop the landscape in ways that will impact negatively on the biodiversity of the area in question. The focus of this study is the relationship between biodiversity stewardship and social learning, as I hope to ascertain how stewardship practices are helping to resolve the current problems of biodiversity loss in the Western Cape. The overall aim of this research is to gain an understanding of how, in its capacity as a conservation education process, the Cape Nature Stewardship Programme can foster social learning amongst the landowners involved in its implementation, by leading them to a better understanding of their environmental responsibilities. Data was generated through the use of interviews and informal discussions with participants together with document analysis, such as brochures, pamphlets and presentations. My approach to the analysis of my data was two-phased. In the first phase, I analysed the data generated from the interview process and from reviewing the documents the stewardship officials supplied me with. The second phase involved looking into the results of the two case studies, and formulating analytical statements which were then used to review the case evidence within a social learning perspective, derived from Wals (2007). In constructing an analytical framework for the interpretation of my data, I drew heavily on Wals' (2007) notion of social learning occurring in sequential activities. I used this insight as a lens through which to trace the educational effects of the implementation of the CNSP in the two case study areas.The research highlighted evidence that Stewardship initiatives should be based on the foundation of social learning and invest time and effort in building an environmental knowledge capital amongst the landowners involved. By equipping them with these necessary conservation skills, one creates a 'community of practice' where those individuals adopt a sustainability habitus contributing towards a change and environmental understanding and practises in field.
- Full Text:
Stories from forest, river and mountain : exploring children's cultural environmental narratives and their role in the transmission of cultural connection to and protection of biodiversity
- Authors: Alexander, Jamie Kim
- Date: 2011
- Subjects: Children and the environment -- South Africa -- Eastern Cape , Conservation of natural resources -- South Africa -- Eastern Cape -- Citizen participation , Environmental education -- South Africa -- Eastern Cape , Human ecology -- South Africa -- Eastern Cape , Oral tradition -- South Africa -- Eastern Cape , Social learning -- South Africa -- Eastern Cape , Traditional ecological knowledge -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:6061 , http://hdl.handle.net/10962/d1015267
- Description: Preservationist conservation created a legacy of national parks and protected areas that were surrounded by local people dispossessed of their land and denied the rights to use the resources they had previously relied upon. Although conservation is now shifting towards a more participatory approach, research gaps still exist in determining the meaning of 'the environment' and the role of local means of conservation in rural communities in South Africa. This study focused on children's cultural environmental narratives from two rural villages in the Eastern Cape, South Africa. Children from grades 4, 7 and 10 were involved in the study, and adult family members, local experts and village elders were included in the study to allow for comparison between children's and adult's narratives and to realise what Local Ecological Knowledge (LEK) was being passed on. This thesis considers children's use of the environment for play and their sense of place as key methods in ascertaining children's environmental narratives and perceptions. At both field sites, local experts and community elders possessed a wealth of cultural environmental narratives, but these narratives were not necessarily being passed on. Changing household structures and other socio-economic factors influence cultural environmental practices, which in turn have an impact on the cultural environmental narratives being passed down. In many cases, parents' safety fears strongly impacted upon children's access to the environment, resulting in gendered environmental knowledge. The study compared differing vegetation types and degrees of environmental access. The differing environments produced similar cultural environmental narratives, leading to new understandings in community environment relationships. Children living near the state administered forest had significantly less environmental knowledge, bringing about questions of sustainable bio-cultural diversity in the future. The recognition of cultural environmental values is especially important in the rural areas of South Africa, where unemployment and increased poverty levels have led to greater dependence on natural resources for social, economic and cultural purposes. It is proposed that local cultural environmental narratives and landscape perceptions be included into community conservation and environmental education policies and programmes to provide local solutions to the problem of biodiversity conservation in local contexts.
- Full Text:
- Authors: Alexander, Jamie Kim
- Date: 2011
- Subjects: Children and the environment -- South Africa -- Eastern Cape , Conservation of natural resources -- South Africa -- Eastern Cape -- Citizen participation , Environmental education -- South Africa -- Eastern Cape , Human ecology -- South Africa -- Eastern Cape , Oral tradition -- South Africa -- Eastern Cape , Social learning -- South Africa -- Eastern Cape , Traditional ecological knowledge -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:6061 , http://hdl.handle.net/10962/d1015267
- Description: Preservationist conservation created a legacy of national parks and protected areas that were surrounded by local people dispossessed of their land and denied the rights to use the resources they had previously relied upon. Although conservation is now shifting towards a more participatory approach, research gaps still exist in determining the meaning of 'the environment' and the role of local means of conservation in rural communities in South Africa. This study focused on children's cultural environmental narratives from two rural villages in the Eastern Cape, South Africa. Children from grades 4, 7 and 10 were involved in the study, and adult family members, local experts and village elders were included in the study to allow for comparison between children's and adult's narratives and to realise what Local Ecological Knowledge (LEK) was being passed on. This thesis considers children's use of the environment for play and their sense of place as key methods in ascertaining children's environmental narratives and perceptions. At both field sites, local experts and community elders possessed a wealth of cultural environmental narratives, but these narratives were not necessarily being passed on. Changing household structures and other socio-economic factors influence cultural environmental practices, which in turn have an impact on the cultural environmental narratives being passed down. In many cases, parents' safety fears strongly impacted upon children's access to the environment, resulting in gendered environmental knowledge. The study compared differing vegetation types and degrees of environmental access. The differing environments produced similar cultural environmental narratives, leading to new understandings in community environment relationships. Children living near the state administered forest had significantly less environmental knowledge, bringing about questions of sustainable bio-cultural diversity in the future. The recognition of cultural environmental values is especially important in the rural areas of South Africa, where unemployment and increased poverty levels have led to greater dependence on natural resources for social, economic and cultural purposes. It is proposed that local cultural environmental narratives and landscape perceptions be included into community conservation and environmental education policies and programmes to provide local solutions to the problem of biodiversity conservation in local contexts.
- Full Text:
Studies in South African marine molluscan chemistry
- Authors: Bromley, Candice Leigh
- Date: 2011
- Subjects: Mollusks -- South Africa , Marine invertebrates -- South Africa , Marine metabolites -- South Africa , Chemical oceanography -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4356 , http://hdl.handle.net/10962/d1005021
- Description: This thesis investigates the variability occurring in the secondary metabolites produced by three South African marine molluscs. Chapter Two discusses the isolation and spectroscopic structure elucidation of the metabolites isolated from two Siphonaria species. The re-investigation of Siphonaria capensis yielded siphonarienfuranone (2.2) as the only common polypropionate isolated from both the 1998 and 2009 collections of S. capensis from the same areas suggesting possible seasonal or genetic variation in polypropionate production. The sterol cholest-7-en-3,5,7- triol (2.33) was also isolated form the 2009 collection of S. capensis and this is the first time this compound has been isolated from a Siphonaria species. The second species, Siphonaria oculus is closely related to S. capensis and the investigation into the former’s secondary metaboliteproduction revealed 2.2 as a major metabolite suggesting an inter-species overlap in polypropionate production. Three new polypropionate metabolites, 2.35, 2.36 and 2.37 were also isolated from S. oculus. An unsuccessful attempt was made to establish the absolute configuration of 2.37 using the modified Mosher’s method and the limited amount of 2.37 available prevented any further attempts at resolving the absolute configuration of this compound. The 1H NMR analysis of the defensive mucus collected directly from S. oculus revealed the presence of the acyclic polypropionate 2.37 as a minor metabolite. The absence of characteristic signals for the furanone containing compounds 2.2, 2.35 and 2.36, might suggest that these compounds cyclise from a hypothetical acyclic precursor (2.38) during standard work up of bulk acetone extracts of Siphonaria species. Chapter Three discusses the re-isolation and spectroscopic structure elucidation of the metabolites isolated from the nudibranch, Leminda millecra. Three known natural products, millecrone A (3.1), 8-hydroxycalamenene (3.6) and cubebenone (3.8) were re-isolated from our 2010 collection of L. millecra, as well as the new minor metabolite 8-acetoxycalamenene (3.16). The cytotoxic prenylated toluquinones and toluhydroquinones (3.9-3.15) initially isolated from the 1998 collection of L. millecra were not found in the 2010 collection supporting the hypothesis that these compounds may be of fungal origin. L. millecra clearly shows variability in the compounds sequestered by this species with millecrone A (3.1) being the only common metabolite in the three investigations of L. millecra to date. An unsuccessful attempt was made to establish the absolute configuration of 3.1, 3.6 and 3.8 through initial LAH reduction of the ketone moiety contained in 3.1 and 3.8 and esterification of the resultant diastereomeric alcohol mixtures and the phenol functionality in 3.6 with (1S)-camphanic chloride. Crystallisation of the (S)- camphanate esters of 3.6 and 3.8 for X-ray analysis were unsuccessful, while the unexpected conjugate addition of a hydride in 3.1 resulted in complex diastereomeric mixtures which could not be separated by HPLC.
- Full Text:
- Authors: Bromley, Candice Leigh
- Date: 2011
- Subjects: Mollusks -- South Africa , Marine invertebrates -- South Africa , Marine metabolites -- South Africa , Chemical oceanography -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4356 , http://hdl.handle.net/10962/d1005021
- Description: This thesis investigates the variability occurring in the secondary metabolites produced by three South African marine molluscs. Chapter Two discusses the isolation and spectroscopic structure elucidation of the metabolites isolated from two Siphonaria species. The re-investigation of Siphonaria capensis yielded siphonarienfuranone (2.2) as the only common polypropionate isolated from both the 1998 and 2009 collections of S. capensis from the same areas suggesting possible seasonal or genetic variation in polypropionate production. The sterol cholest-7-en-3,5,7- triol (2.33) was also isolated form the 2009 collection of S. capensis and this is the first time this compound has been isolated from a Siphonaria species. The second species, Siphonaria oculus is closely related to S. capensis and the investigation into the former’s secondary metaboliteproduction revealed 2.2 as a major metabolite suggesting an inter-species overlap in polypropionate production. Three new polypropionate metabolites, 2.35, 2.36 and 2.37 were also isolated from S. oculus. An unsuccessful attempt was made to establish the absolute configuration of 2.37 using the modified Mosher’s method and the limited amount of 2.37 available prevented any further attempts at resolving the absolute configuration of this compound. The 1H NMR analysis of the defensive mucus collected directly from S. oculus revealed the presence of the acyclic polypropionate 2.37 as a minor metabolite. The absence of characteristic signals for the furanone containing compounds 2.2, 2.35 and 2.36, might suggest that these compounds cyclise from a hypothetical acyclic precursor (2.38) during standard work up of bulk acetone extracts of Siphonaria species. Chapter Three discusses the re-isolation and spectroscopic structure elucidation of the metabolites isolated from the nudibranch, Leminda millecra. Three known natural products, millecrone A (3.1), 8-hydroxycalamenene (3.6) and cubebenone (3.8) were re-isolated from our 2010 collection of L. millecra, as well as the new minor metabolite 8-acetoxycalamenene (3.16). The cytotoxic prenylated toluquinones and toluhydroquinones (3.9-3.15) initially isolated from the 1998 collection of L. millecra were not found in the 2010 collection supporting the hypothesis that these compounds may be of fungal origin. L. millecra clearly shows variability in the compounds sequestered by this species with millecrone A (3.1) being the only common metabolite in the three investigations of L. millecra to date. An unsuccessful attempt was made to establish the absolute configuration of 3.1, 3.6 and 3.8 through initial LAH reduction of the ketone moiety contained in 3.1 and 3.8 and esterification of the resultant diastereomeric alcohol mixtures and the phenol functionality in 3.6 with (1S)-camphanic chloride. Crystallisation of the (S)- camphanate esters of 3.6 and 3.8 for X-ray analysis were unsuccessful, while the unexpected conjugate addition of a hydride in 3.1 resulted in complex diastereomeric mixtures which could not be separated by HPLC.
- Full Text:
Teaching reading in Rukwangali in four Grade 3 Namibian classrooms : a case study
- Authors: Siyave, Theresia Nerumbu
- Date: 2011
- Subjects: Reading (Elementary) -- Namibia Reading teachers -- Training of -- Namibia Kwangali language -- Study and teaching (Elementary) -- Namibia Literacy -- Study and teaching (Elementary) -- Namibia Native language and education -- Study and teaching (Elementary) -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1798 , http://hdl.handle.net/10962/d1003683
- Description: This study aims to explore four grade 3 teachers’ understanding of teaching reading in Rukwangali, a home language in Namibia in Kavango region and to observe the strategies they use as well as the activities they set for their learners. During my School Based Studies (SBS), I noticed that learners were not reading with understanding. My interest was also stimulated by a study carried out in Namibia that found that the literacy levels for Namibian learners were poor compared to those of other African countries. This is a qualitative case study carried out within an interpretive paradigm. It seeks to understand the meaning that people attached to human actions. I selected the participants purposefully and in terms of convenience, as all three schools selected are situated in Rundu, the town in which I work as a college lecturer. The research tools I employed were semi-structured interviews, document analysis, classroom observation, and stimulated recall discussions on the lessons I observed. I used a variety of methods to triangulate data and enhance validity. This study reveals that teachers use multiple methods to teach reading. These methods include phonics and syllabification to help struggling learners to decode difficult and long (polysyllabic) words and the look-and-say method for whole word recognition and meaning making at word and sentence level. In addition, they also use the thematic approach to teaching and learning to expand learners’ vocabulary and enhance their understanding of the texts they read and to make their lessons learnercentred. However, the problems of language, lack of reading books written in Rukwangali and large class sizes constrain the teachers from teaching in a more learner-centred way. Therefore, the study gives some tentative recommendations to remedy this situation.
- Full Text:
- Authors: Siyave, Theresia Nerumbu
- Date: 2011
- Subjects: Reading (Elementary) -- Namibia Reading teachers -- Training of -- Namibia Kwangali language -- Study and teaching (Elementary) -- Namibia Literacy -- Study and teaching (Elementary) -- Namibia Native language and education -- Study and teaching (Elementary) -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1798 , http://hdl.handle.net/10962/d1003683
- Description: This study aims to explore four grade 3 teachers’ understanding of teaching reading in Rukwangali, a home language in Namibia in Kavango region and to observe the strategies they use as well as the activities they set for their learners. During my School Based Studies (SBS), I noticed that learners were not reading with understanding. My interest was also stimulated by a study carried out in Namibia that found that the literacy levels for Namibian learners were poor compared to those of other African countries. This is a qualitative case study carried out within an interpretive paradigm. It seeks to understand the meaning that people attached to human actions. I selected the participants purposefully and in terms of convenience, as all three schools selected are situated in Rundu, the town in which I work as a college lecturer. The research tools I employed were semi-structured interviews, document analysis, classroom observation, and stimulated recall discussions on the lessons I observed. I used a variety of methods to triangulate data and enhance validity. This study reveals that teachers use multiple methods to teach reading. These methods include phonics and syllabification to help struggling learners to decode difficult and long (polysyllabic) words and the look-and-say method for whole word recognition and meaning making at word and sentence level. In addition, they also use the thematic approach to teaching and learning to expand learners’ vocabulary and enhance their understanding of the texts they read and to make their lessons learnercentred. However, the problems of language, lack of reading books written in Rukwangali and large class sizes constrain the teachers from teaching in a more learner-centred way. Therefore, the study gives some tentative recommendations to remedy this situation.
- Full Text:
Teaching struggling adolescent readers in Namibia : a case study
- Authors: Simanga, Elizabeth Miyaze
- Date: 2011
- Subjects: Reading (Secondary) -- Namibia Reading comprehension -- Study and teaching (Secondary) -- Namibia Reading -- Remedial teaching -- Namibia Reading teachers -- Training of -- Namibia Second language acquisition -- Namibia English language -- Study and teaching -- Foreign speakers -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1876 , http://hdl.handle.net/10962/d1005639
- Description: Though research has been conducted on many issues since Namibia's independence in 1990, none of these studies has investigated how English Second Language (ESL) teachers teach and support struggling adolescent readers (SARs) to read. Utilising qualitative research techniques such as classroom observations, semi-structured interviews and document analysis, this case study looked at strategies, methods, and resources used by five ESL secondary school teachers to teach SARs to read in two regions in Namibia, Caprivi and Otjozondjupa regions. Two of the five participants were male teachers. The presence of SARs in the classes observed was established by using informal methods such as the ESL teachers' experience (Caprivi region), while a sample of questions from PIRLS 2001 (Mullis, Martin, Gonzalez, & Kennedy (2003) was compiled to form a test used in the Otjozondjupa region. The findings show that despite undergoing initial teacher training and majoring in English, the five ESL secondary school teachers were not trained to teach SARs either how to read or how to support them. In addition, the study found that there was a shortage of reading materials in all five selected schools.
- Full Text:
- Authors: Simanga, Elizabeth Miyaze
- Date: 2011
- Subjects: Reading (Secondary) -- Namibia Reading comprehension -- Study and teaching (Secondary) -- Namibia Reading -- Remedial teaching -- Namibia Reading teachers -- Training of -- Namibia Second language acquisition -- Namibia English language -- Study and teaching -- Foreign speakers -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1876 , http://hdl.handle.net/10962/d1005639
- Description: Though research has been conducted on many issues since Namibia's independence in 1990, none of these studies has investigated how English Second Language (ESL) teachers teach and support struggling adolescent readers (SARs) to read. Utilising qualitative research techniques such as classroom observations, semi-structured interviews and document analysis, this case study looked at strategies, methods, and resources used by five ESL secondary school teachers to teach SARs to read in two regions in Namibia, Caprivi and Otjozondjupa regions. Two of the five participants were male teachers. The presence of SARs in the classes observed was established by using informal methods such as the ESL teachers' experience (Caprivi region), while a sample of questions from PIRLS 2001 (Mullis, Martin, Gonzalez, & Kennedy (2003) was compiled to form a test used in the Otjozondjupa region. The findings show that despite undergoing initial teacher training and majoring in English, the five ESL secondary school teachers were not trained to teach SARs either how to read or how to support them. In addition, the study found that there was a shortage of reading materials in all five selected schools.
- Full Text:
Testing the existence and direction of "spill-over" of mussel recruits beyond the boundaries of marine protected areas
- Authors: Ludford, Adam
- Date: 2011
- Subjects: Marine parks and reserves -- South Africa -- Transkei , Marine resources conservation -- South Africa -- Transkei , Mussels -- Ecology -- South Africa -- Transkei , Mexilhao mussel -- Reproduction -- South Africa -- Transkei , Mexilhao mussel -- Behavior -- South Africa -- Transkei
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5786 , http://hdl.handle.net/10962/d1005474 , Marine parks and reserves -- South Africa -- Transkei , Marine resources conservation -- South Africa -- Transkei , Mussels -- Ecology -- South Africa -- Transkei , Mexilhao mussel -- Reproduction -- South Africa -- Transkei , Mexilhao mussel -- Behavior -- South Africa -- Transkei
- Description: Landscape ecology helps in predicting the influence of habitat fragmentation on populations. Marine protected areas (MPAs) are expected to create areas of good quality patches and so improve connectivity among shores. MPAs are believed not only to protect adult populations, but also to enhance recruitment both within MPAs and on surrounding exploited shores, therefore improving their ability to recover from overexploitation. As such, MPAs are a preferred management tool for the conservation of natural populations. Although MPAs have been demonstrated to enhance adult abundances, little work has been done on their ability to provide so called "spill-over" of recruits nor has the generality of the influence of MPAs been investigated in a single region with multiple control sites. The Transkei region, on the east coast of South Africa, and the intertidal mussel, Perna perna, offer an ideal system to test the generality of the influence of MPAs on surrounding shores, due to the presence of multiple MPAs and exploited control sites. Patterns of adult abundance were surveyed at four MPAs and two comparably sized exploited control sites. Adult abundances were, in general, found to be higher within MPAs than at exploited control sites, with adult abundances decreasing towards the edge of MPAs and decreasing even more on the outside shores. To simplify the sorting procedure for samples of mussel recruits, a new method using fractionated elutriation was devised and tested. This new method was found to be more accurate, although not statistically significant but also substantially more time consuming. The increase in accuracy although not statistically significant could be biologically significant, especially when looking at low numbers. This new method could, therefore, be very useful especially when [...] is low. Recruitment was estimated over three months during the main reproductive season at two of the MPAs and at appropriate control sites. I predicted that recruitment patterns would mirror the patterns found in adult abundances and that there would be directionality in patterns of recruitment, with northern sites having greater recruitment due to the direction of near-shore ocean currents. Contrary to this, there were no correlations between adult abundance and recruitment for any of the months or sites, with no clear spatial pattern of recruitment in any of the three months. There was, however, a slight trend of greater recruitment at northern sites. To explain the lack of consistency in recruitment and adult abundances, wind data were used to examine the near-shore surface currents in this area, with theoretical surface currents showing similar patterns to those observed for recruitment. From a landscape perspective, the good patches created by MPAs supply recruits to the surrounding matrix but the low quality of habitat in the matrix prevents rehabilitation. The quality of the matrix must therefore be first improved by reseeding these shores. These results emphasise that while MPAs may function in protecting adult abundances, their influence on supplying recruits and hence recovery of near-by exploited shores may be overestimated. This lack of influence on near-by exploited shores highlights the need for reseeding of shores in conjunction with suitable management plans.
- Full Text:
- Authors: Ludford, Adam
- Date: 2011
- Subjects: Marine parks and reserves -- South Africa -- Transkei , Marine resources conservation -- South Africa -- Transkei , Mussels -- Ecology -- South Africa -- Transkei , Mexilhao mussel -- Reproduction -- South Africa -- Transkei , Mexilhao mussel -- Behavior -- South Africa -- Transkei
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5786 , http://hdl.handle.net/10962/d1005474 , Marine parks and reserves -- South Africa -- Transkei , Marine resources conservation -- South Africa -- Transkei , Mussels -- Ecology -- South Africa -- Transkei , Mexilhao mussel -- Reproduction -- South Africa -- Transkei , Mexilhao mussel -- Behavior -- South Africa -- Transkei
- Description: Landscape ecology helps in predicting the influence of habitat fragmentation on populations. Marine protected areas (MPAs) are expected to create areas of good quality patches and so improve connectivity among shores. MPAs are believed not only to protect adult populations, but also to enhance recruitment both within MPAs and on surrounding exploited shores, therefore improving their ability to recover from overexploitation. As such, MPAs are a preferred management tool for the conservation of natural populations. Although MPAs have been demonstrated to enhance adult abundances, little work has been done on their ability to provide so called "spill-over" of recruits nor has the generality of the influence of MPAs been investigated in a single region with multiple control sites. The Transkei region, on the east coast of South Africa, and the intertidal mussel, Perna perna, offer an ideal system to test the generality of the influence of MPAs on surrounding shores, due to the presence of multiple MPAs and exploited control sites. Patterns of adult abundance were surveyed at four MPAs and two comparably sized exploited control sites. Adult abundances were, in general, found to be higher within MPAs than at exploited control sites, with adult abundances decreasing towards the edge of MPAs and decreasing even more on the outside shores. To simplify the sorting procedure for samples of mussel recruits, a new method using fractionated elutriation was devised and tested. This new method was found to be more accurate, although not statistically significant but also substantially more time consuming. The increase in accuracy although not statistically significant could be biologically significant, especially when looking at low numbers. This new method could, therefore, be very useful especially when [...] is low. Recruitment was estimated over three months during the main reproductive season at two of the MPAs and at appropriate control sites. I predicted that recruitment patterns would mirror the patterns found in adult abundances and that there would be directionality in patterns of recruitment, with northern sites having greater recruitment due to the direction of near-shore ocean currents. Contrary to this, there were no correlations between adult abundance and recruitment for any of the months or sites, with no clear spatial pattern of recruitment in any of the three months. There was, however, a slight trend of greater recruitment at northern sites. To explain the lack of consistency in recruitment and adult abundances, wind data were used to examine the near-shore surface currents in this area, with theoretical surface currents showing similar patterns to those observed for recruitment. From a landscape perspective, the good patches created by MPAs supply recruits to the surrounding matrix but the low quality of habitat in the matrix prevents rehabilitation. The quality of the matrix must therefore be first improved by reseeding these shores. These results emphasise that while MPAs may function in protecting adult abundances, their influence on supplying recruits and hence recovery of near-by exploited shores may be overestimated. This lack of influence on near-by exploited shores highlights the need for reseeding of shores in conjunction with suitable management plans.
- Full Text:
Textual representations of migrants and the process of migration in selected South African media a combined critical discourse analysis and corpus linguistics study
- Authors: Crymble, Leigh
- Date: 2011
- Subjects: Immigrants in mass media -- South Africa Mass media and foreign workers -- South Africa Refugees -- Press coverage -- South Africa Xenophobia in mass media -- South Africa Critical discourse analysis Corpora (Linguistics) Sunday Times (Johannesburg, South Africa) City Press (Johannesburg, South Africa) Mail & Guardian
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2342 , http://hdl.handle.net/10962/d1002624
- Description: South Africa has long been associated with racial and ethnic issues surrounding prejudice and discrimination and despite a move post-1994 to a democratic ‘rainbow nation’ society, the country has remained plagued by unequal power relations. One such instance of inequality relates to the marginalisation of migrants which has been realised through xenophobic attitudes and actions, most notably the violence that swept across the country in 2008. Several reasons have been suggested in an attempt to explain the cause of the violence, including claims that migrants are taking ‘our jobs and our women’, migrants are ‘illegal and criminal’ and bringing ‘disease and contamination’ with them from their countries of origin. Although widely accepted that many, if not all, of these beliefs are based on ignorance and hearsay, these extensive generalisations shape and reinforce prejudiced ideologies about migrant communities. It is thus only when confronted with evidence that challenges this dominant discourse, that South Africans are able to reconsider their views. Williams (2008) suggests that for many South Africans, Africa continues to be the ‘dark continent’ that is seen as an ominous, threatening force of which they have very little knowledge. For this reason, anti-immigrant sentiment in a South African context has traditionally been directed at African foreigners. In this study I examine the ways in which African migrants and migrant communities, as well as the overall processes of migration, are depicted by selected South African print media: City Press, Mail & Guardian and Sunday Times. Using a combined Corpus Linguistics and Critical Discourse Analysis approach, I investigate the following questions: How are migrants and the process of migration into South Africa represented by these established newspapers between 2006 and 2010? Are there any differences or similarities between these representations? In particular, what ideologies regarding migrants and migrant communities underlie these representations? My analysis focuses on the landscape of public discourse about migration with an exploration of the rise and fall of the terminologies used to categorise migrants and the social implications of these classifications. Additionally, I analyse the expansive occurrences of negative representations of migrants, particularly through the use of ‘othering’ pronouns ‘us’ versus ‘them’ and through the use of metaphorical language which largely depicts these individuals as en masse natural disasters. I conclude that these discursive elements play a crucial role in contributing to an overall xenophobic rhetoric. Despite subtle differences between the three newspapers which can be accounted for based on their political persuasions and agendas, it is surprising to note how aligned these publications are with regard to their portrayal of migrants. With a few exceptions, this representation positions these individuals as powerless and disenfranchised and maintains the status quo view of migrants as burdens on the South African economy and resources. Overall, the newspaper articles contribute to mainstream dominant discourse on migrants and migration with the underlying ideology that migrants are responsible for the hardships suffered by South African citizens. Thus, this study contributes significantly to existing bodies of research detailing discourse on migrants and emphasises the intrinsic links between language, ideology and society.
- Full Text:
- Authors: Crymble, Leigh
- Date: 2011
- Subjects: Immigrants in mass media -- South Africa Mass media and foreign workers -- South Africa Refugees -- Press coverage -- South Africa Xenophobia in mass media -- South Africa Critical discourse analysis Corpora (Linguistics) Sunday Times (Johannesburg, South Africa) City Press (Johannesburg, South Africa) Mail & Guardian
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2342 , http://hdl.handle.net/10962/d1002624
- Description: South Africa has long been associated with racial and ethnic issues surrounding prejudice and discrimination and despite a move post-1994 to a democratic ‘rainbow nation’ society, the country has remained plagued by unequal power relations. One such instance of inequality relates to the marginalisation of migrants which has been realised through xenophobic attitudes and actions, most notably the violence that swept across the country in 2008. Several reasons have been suggested in an attempt to explain the cause of the violence, including claims that migrants are taking ‘our jobs and our women’, migrants are ‘illegal and criminal’ and bringing ‘disease and contamination’ with them from their countries of origin. Although widely accepted that many, if not all, of these beliefs are based on ignorance and hearsay, these extensive generalisations shape and reinforce prejudiced ideologies about migrant communities. It is thus only when confronted with evidence that challenges this dominant discourse, that South Africans are able to reconsider their views. Williams (2008) suggests that for many South Africans, Africa continues to be the ‘dark continent’ that is seen as an ominous, threatening force of which they have very little knowledge. For this reason, anti-immigrant sentiment in a South African context has traditionally been directed at African foreigners. In this study I examine the ways in which African migrants and migrant communities, as well as the overall processes of migration, are depicted by selected South African print media: City Press, Mail & Guardian and Sunday Times. Using a combined Corpus Linguistics and Critical Discourse Analysis approach, I investigate the following questions: How are migrants and the process of migration into South Africa represented by these established newspapers between 2006 and 2010? Are there any differences or similarities between these representations? In particular, what ideologies regarding migrants and migrant communities underlie these representations? My analysis focuses on the landscape of public discourse about migration with an exploration of the rise and fall of the terminologies used to categorise migrants and the social implications of these classifications. Additionally, I analyse the expansive occurrences of negative representations of migrants, particularly through the use of ‘othering’ pronouns ‘us’ versus ‘them’ and through the use of metaphorical language which largely depicts these individuals as en masse natural disasters. I conclude that these discursive elements play a crucial role in contributing to an overall xenophobic rhetoric. Despite subtle differences between the three newspapers which can be accounted for based on their political persuasions and agendas, it is surprising to note how aligned these publications are with regard to their portrayal of migrants. With a few exceptions, this representation positions these individuals as powerless and disenfranchised and maintains the status quo view of migrants as burdens on the South African economy and resources. Overall, the newspaper articles contribute to mainstream dominant discourse on migrants and migration with the underlying ideology that migrants are responsible for the hardships suffered by South African citizens. Thus, this study contributes significantly to existing bodies of research detailing discourse on migrants and emphasises the intrinsic links between language, ideology and society.
- Full Text:
The contribution made by Mr Justice EF Watermeyer to South African tax jurisprudence
- Authors: Thackwell, Robert Colin
- Date: 2011
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: vital:881 , http://hdl.handle.net/10962/d1001635
- Description: The objective of this thesis is to highlight the colossal contributions made by the late Justice Watermeyer to South African tax jurisprudence. His contributions are viewed from a practical application point of view as well as from a statutory interpretative perspective. The style and technique with which he delivered his judgments are also considered to be a contribution in their own right. The core of this thesis is the analysis of seven of Justice Watermeyer‟s most influential judgments. The development and application of the principle or principles developed in each of these seven judgments is then traced chronologically through case law up until recent judgments. It is most notable that each and every phrase contained in section 11(a) of the Income Tax Act has been interpreted by Justice Watermeyer. These interpretations are still viewed as correct statements of the applicable law and will continue to be referred to on a regular basis given the fact that section 11(a) is one of the most widely contested provisions in the Income Tax Act. Several references to his approach to statutory interpretation are made through the course of the case analyses. Whilst significant evidence of a purposive oriented approach to interpretation appears in some judgments, such evidence is lacking in others. An absolute or conclusive submission in terms of his approach to statutory interpretation is not sufficiently supported. His style of judgment is also referred to and commented on, with particular focus placed on his use of illustrative examples. The contribution to South African tax law by Justice Watermeyer is found to be nothing short of enormous. He was and continues to be influential with respect to section 11(a),the definition of gross income in section 1, common law principles of tax avoidance as well as the interpretation of statutory laws of tax avoidance. It is anticipated that some of his interpretations with respect to statutory rules of tax avoidance will be referred to when the relatively new anti-avoidance provisions become the subject of litigation.
- Full Text:
- Authors: Thackwell, Robert Colin
- Date: 2011
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: vital:881 , http://hdl.handle.net/10962/d1001635
- Description: The objective of this thesis is to highlight the colossal contributions made by the late Justice Watermeyer to South African tax jurisprudence. His contributions are viewed from a practical application point of view as well as from a statutory interpretative perspective. The style and technique with which he delivered his judgments are also considered to be a contribution in their own right. The core of this thesis is the analysis of seven of Justice Watermeyer‟s most influential judgments. The development and application of the principle or principles developed in each of these seven judgments is then traced chronologically through case law up until recent judgments. It is most notable that each and every phrase contained in section 11(a) of the Income Tax Act has been interpreted by Justice Watermeyer. These interpretations are still viewed as correct statements of the applicable law and will continue to be referred to on a regular basis given the fact that section 11(a) is one of the most widely contested provisions in the Income Tax Act. Several references to his approach to statutory interpretation are made through the course of the case analyses. Whilst significant evidence of a purposive oriented approach to interpretation appears in some judgments, such evidence is lacking in others. An absolute or conclusive submission in terms of his approach to statutory interpretation is not sufficiently supported. His style of judgment is also referred to and commented on, with particular focus placed on his use of illustrative examples. The contribution to South African tax law by Justice Watermeyer is found to be nothing short of enormous. He was and continues to be influential with respect to section 11(a),the definition of gross income in section 1, common law principles of tax avoidance as well as the interpretation of statutory laws of tax avoidance. It is anticipated that some of his interpretations with respect to statutory rules of tax avoidance will be referred to when the relatively new anti-avoidance provisions become the subject of litigation.
- Full Text:
The critical natural capital of the Buffalo City Municipality, South Africa : harnessing local action for biodiversity conservation
- Authors: Hagen, Brett
- Date: 2011
- Subjects: Natural resources -- South Africa -- Buffalo City , Biodiversity conservation -- South Africa -- Buffalo City , Ecosystem services -- South Africa -- Buffalo City , Nature conservation -- South Africa -- Buffalo City , Environmental protection -- South Africa -- Buffalo City , Environmental degradation -- South Africa -- Buffalo City , Restoration ecology -- South Africa -- Buffalo City
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4753 , http://hdl.handle.net/10962/d1007075 , Natural resources -- South Africa -- Buffalo City , Biodiversity conservation -- South Africa -- Buffalo City , Ecosystem services -- South Africa -- Buffalo City , Nature conservation -- South Africa -- Buffalo City , Environmental protection -- South Africa -- Buffalo City , Environmental degradation -- South Africa -- Buffalo City , Restoration ecology -- South Africa -- Buffalo City
- Description: Globally, ecosystems provide services of almost twice the value of global gross national product (Costanza et al., 2006). The Buffalo City Municipality (BCM), South Africa contains biodiversity of national and international importance (Pierce, 2003; Pierce et al., 2005). Despite this, the municipality continues to experience loss of both urban and rural biodiversity (Buffalo City Municipality, 2006a). This study sought to determine the status of biodiversity, and the potential for ecosystem services to contribute to conservation, within the BCM. Biodiversity features, including ecosystem type, species of special concern and biodiversity processes, were identified and mapped using a GIS to produce a biodiversity priority index for the BCM. Current transformation status was then mapped to determine the level of ecosystem degradation within the BCM. Priority biodiversity areas as well as individual biodiversity features were spatially overlain against current transformation status and protected areas and analysed using a GIS to determine the level of degradation and protection of BCM biodiversity. In total 3.5 % of total BCM biodiversity was protected. Of the 24 ecosystem types, 11 (45%) had less than 1% under protection, while 16 (67%) had less than five percent protected. Not restorable areas, thus completely lost to biodiversity conservation, comprised just less than a quarter of the total BCM area while un-impacted areas comprised just 12.3%. Twenty five ecosystem services were identified as being provided by intact natural ecosystems within the BCM. The natural capital providing these services was identified and mapped to produce an ecosystem service index (ESI) using a GIS. This ecosystem service index and the biodiversity priority index were overlain to determine their level of correlation. Overall ESI correlation with priority biodiversity was weak although several individual ecosystem services, including carbon sequestration, showed correlation. Using the above data layers an implementation plan and conservation framework was proposed to assist the coordination of local conservation action within the BCM. It is concluded that ecosystem services are a potentially useful tool for conservationists at the local level seeking to ensure that biodiversity has relevance to and receives protection from broader society.
- Full Text:
- Authors: Hagen, Brett
- Date: 2011
- Subjects: Natural resources -- South Africa -- Buffalo City , Biodiversity conservation -- South Africa -- Buffalo City , Ecosystem services -- South Africa -- Buffalo City , Nature conservation -- South Africa -- Buffalo City , Environmental protection -- South Africa -- Buffalo City , Environmental degradation -- South Africa -- Buffalo City , Restoration ecology -- South Africa -- Buffalo City
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4753 , http://hdl.handle.net/10962/d1007075 , Natural resources -- South Africa -- Buffalo City , Biodiversity conservation -- South Africa -- Buffalo City , Ecosystem services -- South Africa -- Buffalo City , Nature conservation -- South Africa -- Buffalo City , Environmental protection -- South Africa -- Buffalo City , Environmental degradation -- South Africa -- Buffalo City , Restoration ecology -- South Africa -- Buffalo City
- Description: Globally, ecosystems provide services of almost twice the value of global gross national product (Costanza et al., 2006). The Buffalo City Municipality (BCM), South Africa contains biodiversity of national and international importance (Pierce, 2003; Pierce et al., 2005). Despite this, the municipality continues to experience loss of both urban and rural biodiversity (Buffalo City Municipality, 2006a). This study sought to determine the status of biodiversity, and the potential for ecosystem services to contribute to conservation, within the BCM. Biodiversity features, including ecosystem type, species of special concern and biodiversity processes, were identified and mapped using a GIS to produce a biodiversity priority index for the BCM. Current transformation status was then mapped to determine the level of ecosystem degradation within the BCM. Priority biodiversity areas as well as individual biodiversity features were spatially overlain against current transformation status and protected areas and analysed using a GIS to determine the level of degradation and protection of BCM biodiversity. In total 3.5 % of total BCM biodiversity was protected. Of the 24 ecosystem types, 11 (45%) had less than 1% under protection, while 16 (67%) had less than five percent protected. Not restorable areas, thus completely lost to biodiversity conservation, comprised just less than a quarter of the total BCM area while un-impacted areas comprised just 12.3%. Twenty five ecosystem services were identified as being provided by intact natural ecosystems within the BCM. The natural capital providing these services was identified and mapped to produce an ecosystem service index (ESI) using a GIS. This ecosystem service index and the biodiversity priority index were overlain to determine their level of correlation. Overall ESI correlation with priority biodiversity was weak although several individual ecosystem services, including carbon sequestration, showed correlation. Using the above data layers an implementation plan and conservation framework was proposed to assist the coordination of local conservation action within the BCM. It is concluded that ecosystem services are a potentially useful tool for conservationists at the local level seeking to ensure that biodiversity has relevance to and receives protection from broader society.
- Full Text:
The democratisation of art CAP as an alternative art space in South Africa
- Authors: Lochner, Eben
- Date: 2011
- Subjects: Arts and society -- South Africa Democracy and the arts -- South Africa Art -- Political aspects -- South Africa Apartheid and art -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2409 , http://hdl.handle.net/10962/d1002205
- Description: While formal arts education was inaccessible to many during Apartheid, community-based centres played a significant role in the training of previously disadvantaged artists. By engaging in a socio-political critique of the history of South African art, this thesis argues that even though alternative art spaces are often marginalised, they remain essential to the diversification and democratisation of contemporary South African art today with its re-entry into the international art scene. According to Lize van Robbroeck (2004:52), “some of the fundamental ideals of community arts need to be revised to enrich, democratize and diversify [South Africa's] cultural practice.” The aim of my Thesis is to investigate this statement in relation to the contribution the Community Arts Project (CAP) in Cape Town (1977-2003). CAP and other art centres have played an indispensable role in the establishment of black artists and in producing a locally reflective artistic practice in South Africa, even into the 21st century. Through researching the changes the organisation underwent between the 1980s and 1990s, the ways in which such art centres constantly need to respond to the changing sociopolitical landscape around them become clear. Within South Africa these centres were seen to play a significant part in the liberation struggle and then later in nation building. While these centres were well supported by foreign donors in the late 1980s, such funding was withdrawn in 1991 and the majority of art centres collapsed, illustrating to some degree that the training of artist was not valued outside the context of the struggle against apartheid. By interviewing key people and by reading documentation stored at the Manuscripts and Archives department of UCT I have discovered some of the different benefits and hindrances of working in community art centres both during and after Apartheid. This thesis argues that these centres still play a vital role in contributing to the development of South Africa's local art practice and should not be relegated to the sideline.
- Full Text:
- Authors: Lochner, Eben
- Date: 2011
- Subjects: Arts and society -- South Africa Democracy and the arts -- South Africa Art -- Political aspects -- South Africa Apartheid and art -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2409 , http://hdl.handle.net/10962/d1002205
- Description: While formal arts education was inaccessible to many during Apartheid, community-based centres played a significant role in the training of previously disadvantaged artists. By engaging in a socio-political critique of the history of South African art, this thesis argues that even though alternative art spaces are often marginalised, they remain essential to the diversification and democratisation of contemporary South African art today with its re-entry into the international art scene. According to Lize van Robbroeck (2004:52), “some of the fundamental ideals of community arts need to be revised to enrich, democratize and diversify [South Africa's] cultural practice.” The aim of my Thesis is to investigate this statement in relation to the contribution the Community Arts Project (CAP) in Cape Town (1977-2003). CAP and other art centres have played an indispensable role in the establishment of black artists and in producing a locally reflective artistic practice in South Africa, even into the 21st century. Through researching the changes the organisation underwent between the 1980s and 1990s, the ways in which such art centres constantly need to respond to the changing sociopolitical landscape around them become clear. Within South Africa these centres were seen to play a significant part in the liberation struggle and then later in nation building. While these centres were well supported by foreign donors in the late 1980s, such funding was withdrawn in 1991 and the majority of art centres collapsed, illustrating to some degree that the training of artist was not valued outside the context of the struggle against apartheid. By interviewing key people and by reading documentation stored at the Manuscripts and Archives department of UCT I have discovered some of the different benefits and hindrances of working in community art centres both during and after Apartheid. This thesis argues that these centres still play a vital role in contributing to the development of South Africa's local art practice and should not be relegated to the sideline.
- Full Text:
The demography and population dynamics of a re-introduced black rhinoceros population on the Great Fish River Reserve, Eastern Cape Province
- Authors: Fike, Bradley Robin
- Date: 2011
- Subjects: Black rhinoceros -- South Africa -- Great Fish River Valley , Population biology -- South Africa -- Great Fish River Valley , Black rhinoceros -- Habitat -- South Africa -- Great Fish River Valley , Black rhinoceros -- Adaptation -- South Africa -- Great Fish River Valley , Black rhinoceros -- Ecology -- South Africa -- Great Fish River Valley
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5948 , http://hdl.handle.net/10962/d1020869
- Description: The re-introduction of black rhinoceros onto the Great Fish River Reserve in the Eastern Cape, following the species absence for over a century, created an opportunity to study this species in the thicket biome, and in particular the succulent thicket of the Great Fish River valley. The thicket biome is quite different from the habitats in which other extant populations of these animals are found and where studies of their demography have been undertaken. Data collection occurred from May 1986, with the arrival of the first four animals to December 2008, when the population was estimated to be 144 individuals. A variety of monitoring techniques were used including direct ground observations, aerial helicopter census, aerial monitoring by microlight aircraft, camera traps and opportunistic observations, each with its own advantages and disadvantages. The combination of methods and effort has resulted in the population being recognized as completely known with up to 97% of the animals being located at least once per year with a mean frequency of sightings of 11.5 per animal per year. In 2008, the population was about 20% juvenile, 36% sub-adult and 44% adult with a female biased sex ratio of 1.3 females per male. Mean age at first birth was about 80 months and this increased significantly with increasing density of black rhinoceroses. Mean intercalf interval was about 28 months and 41% of adult females gave birth each year. Mortality rates were low for juveniles, higher for sub-adults and higher for males than females. There was a weak but significant positive effect of density on male mortality. Population growth rate was about 10% and was not significantly affected by density. These results suggest that this population is beginning to show the first indications of density dependant constraints and that harvesting should be implemented in order to maintain the productive tempo. A secondary goal of the Management Plan will then be realized as the population functions as a donor to establish founder populations elsewhere within the Diceros bicornis minor range.
- Full Text:
- Authors: Fike, Bradley Robin
- Date: 2011
- Subjects: Black rhinoceros -- South Africa -- Great Fish River Valley , Population biology -- South Africa -- Great Fish River Valley , Black rhinoceros -- Habitat -- South Africa -- Great Fish River Valley , Black rhinoceros -- Adaptation -- South Africa -- Great Fish River Valley , Black rhinoceros -- Ecology -- South Africa -- Great Fish River Valley
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5948 , http://hdl.handle.net/10962/d1020869
- Description: The re-introduction of black rhinoceros onto the Great Fish River Reserve in the Eastern Cape, following the species absence for over a century, created an opportunity to study this species in the thicket biome, and in particular the succulent thicket of the Great Fish River valley. The thicket biome is quite different from the habitats in which other extant populations of these animals are found and where studies of their demography have been undertaken. Data collection occurred from May 1986, with the arrival of the first four animals to December 2008, when the population was estimated to be 144 individuals. A variety of monitoring techniques were used including direct ground observations, aerial helicopter census, aerial monitoring by microlight aircraft, camera traps and opportunistic observations, each with its own advantages and disadvantages. The combination of methods and effort has resulted in the population being recognized as completely known with up to 97% of the animals being located at least once per year with a mean frequency of sightings of 11.5 per animal per year. In 2008, the population was about 20% juvenile, 36% sub-adult and 44% adult with a female biased sex ratio of 1.3 females per male. Mean age at first birth was about 80 months and this increased significantly with increasing density of black rhinoceroses. Mean intercalf interval was about 28 months and 41% of adult females gave birth each year. Mortality rates were low for juveniles, higher for sub-adults and higher for males than females. There was a weak but significant positive effect of density on male mortality. Population growth rate was about 10% and was not significantly affected by density. These results suggest that this population is beginning to show the first indications of density dependant constraints and that harvesting should be implemented in order to maintain the productive tempo. A secondary goal of the Management Plan will then be realized as the population functions as a donor to establish founder populations elsewhere within the Diceros bicornis minor range.
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The design and synthesis of multidentate N-heterocyclic carbenes as metathesis catalyst ligands
- Authors: Truscott, Byron John
- Date: 2011
- Subjects: Carbenes (Methylene compounds) , Heterocyclic compounds , Ligands , Ligands -- Design , Metathesis (Chemistry) , Catalysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4304 , http://hdl.handle.net/10962/d1004962 , Carbenes (Methylene compounds) , Heterocyclic compounds , Ligands , Ligands -- Design , Metathesis (Chemistry) , Catalysis
- Description: This study has focused on the design and preparation of bi– and tridentate N–Heterocyclic Carbene (NHC) ligands in order to investigate the effect of a multidentate approach to the formation, stability and catalytic activity of coordination complexes. Chapters 1 – 3 provide background information of relevant catalysis, carbene and coordination chemistry, followed by previous work performed within our research group. In Chapter 4 attention is given to the synthetic aspects of the research conducted, comprising two distinct approaches to the preparation of unsymmetrical saturated and unsaturated NHCs. Firstly, an investigation of the saturated NHC ligands yielded three novel, unsymmetrical pro–ligands, viz., two halopropyl imidazolinium salts and a bidentate hydroxypropyl imidazolinium salt. Secondly, eight imidazolium salts have been generated, including a hydroxypropyl analogue and novel decyl and tridentate malonyl derivatives. These compounds were prepared using microwave–assisted methodology for the alkylation of N– mesitylimidazole – an approach that drastically reduced reaction times (from 8 hours – 7 days to ca. 0.5 – 2 hours) and facilitated isolation of the imidazolium salts. Many of the compounds prepared in this study are novel and were fully characterized using HRMS and 1– and 2–D NMR analysis. Coordination studies using a selection of the prepared pro–ligands afforded an alkoxy–NHC silver derivative and four novel Ru–complexes, viz., Grubbs II–type Ru–complexes containing:– chloropropyl imidazolinylidene; propenyl imidazolylidene; and bidentate alkoxypropyl imidazolylidene ligands. Furthermore, a well–defined benzyl mesitylimidazolylidene Ru–complex has been isolated, which exhibited good stability in air. DFT–level geometry–optimization studies, using the Accelrys DMol3 package have given valuable insights into the likely geometries of the prepared and putative catalysts.
- Full Text:
- Authors: Truscott, Byron John
- Date: 2011
- Subjects: Carbenes (Methylene compounds) , Heterocyclic compounds , Ligands , Ligands -- Design , Metathesis (Chemistry) , Catalysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4304 , http://hdl.handle.net/10962/d1004962 , Carbenes (Methylene compounds) , Heterocyclic compounds , Ligands , Ligands -- Design , Metathesis (Chemistry) , Catalysis
- Description: This study has focused on the design and preparation of bi– and tridentate N–Heterocyclic Carbene (NHC) ligands in order to investigate the effect of a multidentate approach to the formation, stability and catalytic activity of coordination complexes. Chapters 1 – 3 provide background information of relevant catalysis, carbene and coordination chemistry, followed by previous work performed within our research group. In Chapter 4 attention is given to the synthetic aspects of the research conducted, comprising two distinct approaches to the preparation of unsymmetrical saturated and unsaturated NHCs. Firstly, an investigation of the saturated NHC ligands yielded three novel, unsymmetrical pro–ligands, viz., two halopropyl imidazolinium salts and a bidentate hydroxypropyl imidazolinium salt. Secondly, eight imidazolium salts have been generated, including a hydroxypropyl analogue and novel decyl and tridentate malonyl derivatives. These compounds were prepared using microwave–assisted methodology for the alkylation of N– mesitylimidazole – an approach that drastically reduced reaction times (from 8 hours – 7 days to ca. 0.5 – 2 hours) and facilitated isolation of the imidazolium salts. Many of the compounds prepared in this study are novel and were fully characterized using HRMS and 1– and 2–D NMR analysis. Coordination studies using a selection of the prepared pro–ligands afforded an alkoxy–NHC silver derivative and four novel Ru–complexes, viz., Grubbs II–type Ru–complexes containing:– chloropropyl imidazolinylidene; propenyl imidazolylidene; and bidentate alkoxypropyl imidazolylidene ligands. Furthermore, a well–defined benzyl mesitylimidazolylidene Ru–complex has been isolated, which exhibited good stability in air. DFT–level geometry–optimization studies, using the Accelrys DMol3 package have given valuable insights into the likely geometries of the prepared and putative catalysts.
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The development and assessment of a fixed dose combination tablet of Ranitidine and Metronidazole
- Authors: King'ori, Loti David
- Date: 2011 , 2011-04-07
- Subjects: Ulcers -- Treatment , Ranitidine -- Evaluation , Metronidazole -- Evaluation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3858 , http://hdl.handle.net/10962/d1013359
- Description: The oral route of drug administration is convenient since it is acceptable to most patients and the manufacturing processes used to produce tablets and capsules are relatively simple when compared to those used to manufacture other types of dosage forms. Metronidazole (MTZ) and Ranitidine (RTD) have been used in combination, as part of triple therapy for the treatment of ulcers. However the use of large numbers of tablets and long duration of therapy makes adherence to drug treatment challenging for patients. Therefore the formulation of a fixed dose combination (FDC) of MTZ and RTD may improve patient adherence to therapy and consequently may reduce morbidity and mortality due to ulcers. A stability indicating HPLC method for the simultaneous analysis of MTZ and RTD was developed and validated according to the International Conference on Harmonization (ICH) guidelines. The method was sensitive, selective, precise, accurate and linear.Preformulation studies were performed on the active pharmaceutical ingredients (API) alone and in combination with potential excipients. Differential scanning calorimetry (DSC) studies revealed a potential interaction between MTZ and RTD, however the interaction was not apparent following IR analysis of the same samples. DSC analyses of the API in combination with potential excipients revealed that the compounds were compatible with most materials with the exception of a binary mixture of RTD and Dibasic calcium phosphate (DCP) that exhibited a potential interaction. Thermal gravimetric analysis (TGA) of MTZ and RTD revealed that both compounds exhibited thermal stability. The Carrs Index (CI) and Hausner Ratio (HR) values of MTZ and RTD indicated that both compounds exhibited poor flow and compressibility properties, whereas the CI and HR values for (Microcrystalline cellulose) MCC and DCP indicated better flowability and compressibility characteristics.Direct compression and wet granulation processes were assessed to identify a suitable method of manufacture of FDC tablets of MTZ and RTD. The blends were evaluated using bulk and tapped density and the resultant tablets were evaluated for weight uniformity, crushing strength, tensile strength and disintegration time. The wet granulation method of manufacture produced tablets that showed acceptable pharmacotechnical properties: this approach was therefore used as the method of manufacture of FDC tablets of MTZ and RTD. Tablet formulations comprised of API, viz. MTZ and RTD and different compositions of MCC, DCP, Sodium starch glycolate (SSG) and Croscarmellose sodium (CCS), were manufactured in order to screen for an appropriate diluent and disintegrant composition for use in response surface studies. Assays of tablet content and in vitro drug release were undertaken using the validated HPLC method. Tablets in which MCC and CCS were used appeared to produce better assay and dissolution results as compared to those manufactured using DCP and SSG. Consequently a formulation comprised of MCC and CCS was selected and used in studies in which the effect(s) of level two formulation and composition changes as described in the Scale and Post Approval Changes for Immediate Release (SUPAC-IR) Guidelines on tablet disintegration and in vitro release were assessed. A Box-Behnken statistical design was used for the investigation of the effect of input factors, viz. CCS, (Polyvinyl pyrollidone K30) PVP-K30 and magnesium stearate on measured responses, viz. disintegration time and percent drug release in 10 minutes (Q10). CCS appeared to have an inverse linear relationship on disintegration time and a linear relationship with the Q10 for MTZ and RTD, whereas PVP-K30 and magnesium stearate appeared to have an antagonistic effect on the measured responses. Furthermore CCS and magnesium stearate exhibited an interaction that had an agonistic effect on the Q10 value for RTD. A numerical optimization approach was used to predict a formulation composition that would produce tablets that exhibited a disintegration time and Q10 values for MTZ and RTD that fell within the constraints set in our laboratory. The resultant model was found to be accurate and had a percent prediction error of < 5% for all measured response variables.FDC tablets of MTZ and RTD have been successfully produced. The disintegration of the tablet and dissolution of the API were within compendial specifications and the tablets are of suitable quality and have the potential to be further investigated to reduce the pill burden in the treatment of ulcers.
- Full Text:
- Authors: King'ori, Loti David
- Date: 2011 , 2011-04-07
- Subjects: Ulcers -- Treatment , Ranitidine -- Evaluation , Metronidazole -- Evaluation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3858 , http://hdl.handle.net/10962/d1013359
- Description: The oral route of drug administration is convenient since it is acceptable to most patients and the manufacturing processes used to produce tablets and capsules are relatively simple when compared to those used to manufacture other types of dosage forms. Metronidazole (MTZ) and Ranitidine (RTD) have been used in combination, as part of triple therapy for the treatment of ulcers. However the use of large numbers of tablets and long duration of therapy makes adherence to drug treatment challenging for patients. Therefore the formulation of a fixed dose combination (FDC) of MTZ and RTD may improve patient adherence to therapy and consequently may reduce morbidity and mortality due to ulcers. A stability indicating HPLC method for the simultaneous analysis of MTZ and RTD was developed and validated according to the International Conference on Harmonization (ICH) guidelines. The method was sensitive, selective, precise, accurate and linear.Preformulation studies were performed on the active pharmaceutical ingredients (API) alone and in combination with potential excipients. Differential scanning calorimetry (DSC) studies revealed a potential interaction between MTZ and RTD, however the interaction was not apparent following IR analysis of the same samples. DSC analyses of the API in combination with potential excipients revealed that the compounds were compatible with most materials with the exception of a binary mixture of RTD and Dibasic calcium phosphate (DCP) that exhibited a potential interaction. Thermal gravimetric analysis (TGA) of MTZ and RTD revealed that both compounds exhibited thermal stability. The Carrs Index (CI) and Hausner Ratio (HR) values of MTZ and RTD indicated that both compounds exhibited poor flow and compressibility properties, whereas the CI and HR values for (Microcrystalline cellulose) MCC and DCP indicated better flowability and compressibility characteristics.Direct compression and wet granulation processes were assessed to identify a suitable method of manufacture of FDC tablets of MTZ and RTD. The blends were evaluated using bulk and tapped density and the resultant tablets were evaluated for weight uniformity, crushing strength, tensile strength and disintegration time. The wet granulation method of manufacture produced tablets that showed acceptable pharmacotechnical properties: this approach was therefore used as the method of manufacture of FDC tablets of MTZ and RTD. Tablet formulations comprised of API, viz. MTZ and RTD and different compositions of MCC, DCP, Sodium starch glycolate (SSG) and Croscarmellose sodium (CCS), were manufactured in order to screen for an appropriate diluent and disintegrant composition for use in response surface studies. Assays of tablet content and in vitro drug release were undertaken using the validated HPLC method. Tablets in which MCC and CCS were used appeared to produce better assay and dissolution results as compared to those manufactured using DCP and SSG. Consequently a formulation comprised of MCC and CCS was selected and used in studies in which the effect(s) of level two formulation and composition changes as described in the Scale and Post Approval Changes for Immediate Release (SUPAC-IR) Guidelines on tablet disintegration and in vitro release were assessed. A Box-Behnken statistical design was used for the investigation of the effect of input factors, viz. CCS, (Polyvinyl pyrollidone K30) PVP-K30 and magnesium stearate on measured responses, viz. disintegration time and percent drug release in 10 minutes (Q10). CCS appeared to have an inverse linear relationship on disintegration time and a linear relationship with the Q10 for MTZ and RTD, whereas PVP-K30 and magnesium stearate appeared to have an antagonistic effect on the measured responses. Furthermore CCS and magnesium stearate exhibited an interaction that had an agonistic effect on the Q10 value for RTD. A numerical optimization approach was used to predict a formulation composition that would produce tablets that exhibited a disintegration time and Q10 values for MTZ and RTD that fell within the constraints set in our laboratory. The resultant model was found to be accurate and had a percent prediction error of < 5% for all measured response variables.FDC tablets of MTZ and RTD have been successfully produced. The disintegration of the tablet and dissolution of the API were within compendial specifications and the tablets are of suitable quality and have the potential to be further investigated to reduce the pill burden in the treatment of ulcers.
- Full Text:
The development and implementation of a mental toughness training programme for young cricketers
- Authors: Pattison, Stuart
- Date: 2011
- Subjects: Cricket -- Psychological aspects -- South Africa -- Grahamstown , Cricket -- Training -- South Africa -- Grahamstown , Cricket players -- Mental health -- South Africa -- Grahamstown , Mental discipline , Toughness (Personality trait) , Success -- Psychological aspects , Personal coaching -- South Africa -- Grahamstown , School sports -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3037 , http://hdl.handle.net/10962/d1002546 , Cricket -- Psychological aspects -- South Africa -- Grahamstown , Cricket -- Training -- South Africa -- Grahamstown , Cricket players -- Mental health -- South Africa -- Grahamstown , Mental discipline , Toughness (Personality trait) , Success -- Psychological aspects , Personal coaching -- South Africa -- Grahamstown , School sports -- South Africa -- Grahamstown
- Description: Modern research being conducted on Mental Toughness is now shifting away from efforts aimed at developing definitions for the construct and instead moving toward efforts at understanding its development. This particular research study focuses on the development and implementation of a Mental Toughness programme designed specifically for, and tailored exclusively to, the needs of schoolboy cricket at Kingswood College in Grahamstown, Eastern Cape. The programme development was an intricate process and the research procedure was guided by the Organisational Development Process model. Data from a focus group as well as various individual interviews were integrated with currently existing Mental Toughness literature and theory to devise this particular Mental Toughness programme. The programme entails educating the athletes on six specific mental skills and incorporates elements of practical application as well as awareness of the importance and influence of Mental Toughness and mental training in a sporting sphere. The programme took the form of mental skills workshops held over a three week period. An analysis was conducted post-programme to document the experience of the athletes as a result of exposure to the programme. Results drawn from the array of analysis procedures were used to help identify the level of success of the Mental Toughness intervention as well as help validify current Mental Toughness models. In addition to highlighting the benefits as a result of the programme experience, various recommendations were drawn in order to shed light on the programme limitations and assist future researchers with understanding the intricacies behind better and more efficient programme implementation.
- Full Text:
- Authors: Pattison, Stuart
- Date: 2011
- Subjects: Cricket -- Psychological aspects -- South Africa -- Grahamstown , Cricket -- Training -- South Africa -- Grahamstown , Cricket players -- Mental health -- South Africa -- Grahamstown , Mental discipline , Toughness (Personality trait) , Success -- Psychological aspects , Personal coaching -- South Africa -- Grahamstown , School sports -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3037 , http://hdl.handle.net/10962/d1002546 , Cricket -- Psychological aspects -- South Africa -- Grahamstown , Cricket -- Training -- South Africa -- Grahamstown , Cricket players -- Mental health -- South Africa -- Grahamstown , Mental discipline , Toughness (Personality trait) , Success -- Psychological aspects , Personal coaching -- South Africa -- Grahamstown , School sports -- South Africa -- Grahamstown
- Description: Modern research being conducted on Mental Toughness is now shifting away from efforts aimed at developing definitions for the construct and instead moving toward efforts at understanding its development. This particular research study focuses on the development and implementation of a Mental Toughness programme designed specifically for, and tailored exclusively to, the needs of schoolboy cricket at Kingswood College in Grahamstown, Eastern Cape. The programme development was an intricate process and the research procedure was guided by the Organisational Development Process model. Data from a focus group as well as various individual interviews were integrated with currently existing Mental Toughness literature and theory to devise this particular Mental Toughness programme. The programme entails educating the athletes on six specific mental skills and incorporates elements of practical application as well as awareness of the importance and influence of Mental Toughness and mental training in a sporting sphere. The programme took the form of mental skills workshops held over a three week period. An analysis was conducted post-programme to document the experience of the athletes as a result of exposure to the programme. Results drawn from the array of analysis procedures were used to help identify the level of success of the Mental Toughness intervention as well as help validify current Mental Toughness models. In addition to highlighting the benefits as a result of the programme experience, various recommendations were drawn in order to shed light on the programme limitations and assist future researchers with understanding the intricacies behind better and more efficient programme implementation.
- Full Text:
The development and technologizing of selected Sepedi ICT terminology
- Authors: Magagane, Raesetja Linah
- Date: 2011
- Subjects: Northern Sotho language -- Terms and phrases Northern Sotho language -- Terminology Northern Sotho language -- Computer-assisted instruction Communication -- Technological innovations
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3581 , http://hdl.handle.net/10962/d1002156
- Description: It is my wish that the Sepedi language speakers, through the development and technologization of certain Sepedi ICT terminology, are able to operate a computer in their own language, and implement the new developed and technologized ICT terminology (technologization). The pupils and students at their various institutions should be made comfortable in using the developed and technologized Sepedi language terminology. In the long run the Sepedi language speakers should be ensured access to the web in order to find information about Sepedi language, culture and terms in disciplines such as ICT. It is recommended in this thesis that higher learning institutions offer bursaries to students to develop all South African languages in such a manner that they can be used in all high status functions.
- Full Text:
- Authors: Magagane, Raesetja Linah
- Date: 2011
- Subjects: Northern Sotho language -- Terms and phrases Northern Sotho language -- Terminology Northern Sotho language -- Computer-assisted instruction Communication -- Technological innovations
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3581 , http://hdl.handle.net/10962/d1002156
- Description: It is my wish that the Sepedi language speakers, through the development and technologization of certain Sepedi ICT terminology, are able to operate a computer in their own language, and implement the new developed and technologized ICT terminology (technologization). The pupils and students at their various institutions should be made comfortable in using the developed and technologized Sepedi language terminology. In the long run the Sepedi language speakers should be ensured access to the web in order to find information about Sepedi language, culture and terms in disciplines such as ICT. It is recommended in this thesis that higher learning institutions offer bursaries to students to develop all South African languages in such a manner that they can be used in all high status functions.
- Full Text:
The development of an in vitro system for the production of drug metabolites using microsomal enzymes from bovine liver
- Authors: Morrison, Roxanne
- Date: 2011
- Subjects: Drugs -- Metabolism , Xenobiotics -- Metabolism , Metabolites , Drugs -- Testing , Toxicity testing -- In vitro , Doping in horse racing -- Control -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4087 , http://hdl.handle.net/10962/d1007698 , Drugs -- Metabolism , Xenobiotics -- Metabolism , Metabolites , Drugs -- Testing , Toxicity testing -- In vitro , Doping in horse racing -- Control -- Research
- Description: Drug metabolism is a specialised subset of xenobiotic metabolism, pertaining to the breakdown and elimination of pharmaceutical drugs. The enzymes involved in these pathways are the cytochrome P450 family of isozymes. Metabolism is an important factor in determining the pharmacological effects of drugs. The main aim of this study was to develop a system whereby the major metabolites of drugs can be produced in vitro. An in vitro system was developed and optimised using commercially prepared microsomes from rat liver and coumarin (by monitoring its conversion to 7-hydroxycoumarin) as a model. The optimum running conditions for the incubations were 50 μM coumarin, 50 μg protein/ml microsomes, 1 mM NADP⁺, 5 mM G6P and 1U/ml G6PDH incubated for 30 minutes at 38℃. The HPLC method for the detection of coumarin and 7-hydroxycoumarin was also validated with respect to linearity, reproducibility, precision, accuracy and lower limits of detection and quantification. The system developed was then tested using microsomes prepared from fresh bovine liver on these ten drugs of interest in doping control in horse racing: diazepam, nordiazepam, oxazepam, promazine, acepromazine, chlorpromazine, morphine, codeine, etoricoxib and lumiracoxib. The bovine liver microsomes were prepared using differential centrifugation and had activity on a par with the commercial preparations. This in vitro system metabolised the drugs and produced both phase I and II metabolites, similar to those observed in humans and horses in vivo. For example, the major metabolites of the benzodiazepine drug, diazepam, nordiazepam, temazepam and oxazepam as well as the glucuronidated phase II products were all found after incubations with the bovine liver microsomes. The metabolism of the drugs was also investigated in silico using the computational procedure, MetaSite. MetaSite was able to successfully predict known metabolites for most of the drugs studied. Differences were observed from the in vitro incubations and this is most likely due to MetaSite using only human cytochrome P450s for analysis.
- Full Text:
- Authors: Morrison, Roxanne
- Date: 2011
- Subjects: Drugs -- Metabolism , Xenobiotics -- Metabolism , Metabolites , Drugs -- Testing , Toxicity testing -- In vitro , Doping in horse racing -- Control -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4087 , http://hdl.handle.net/10962/d1007698 , Drugs -- Metabolism , Xenobiotics -- Metabolism , Metabolites , Drugs -- Testing , Toxicity testing -- In vitro , Doping in horse racing -- Control -- Research
- Description: Drug metabolism is a specialised subset of xenobiotic metabolism, pertaining to the breakdown and elimination of pharmaceutical drugs. The enzymes involved in these pathways are the cytochrome P450 family of isozymes. Metabolism is an important factor in determining the pharmacological effects of drugs. The main aim of this study was to develop a system whereby the major metabolites of drugs can be produced in vitro. An in vitro system was developed and optimised using commercially prepared microsomes from rat liver and coumarin (by monitoring its conversion to 7-hydroxycoumarin) as a model. The optimum running conditions for the incubations were 50 μM coumarin, 50 μg protein/ml microsomes, 1 mM NADP⁺, 5 mM G6P and 1U/ml G6PDH incubated for 30 minutes at 38℃. The HPLC method for the detection of coumarin and 7-hydroxycoumarin was also validated with respect to linearity, reproducibility, precision, accuracy and lower limits of detection and quantification. The system developed was then tested using microsomes prepared from fresh bovine liver on these ten drugs of interest in doping control in horse racing: diazepam, nordiazepam, oxazepam, promazine, acepromazine, chlorpromazine, morphine, codeine, etoricoxib and lumiracoxib. The bovine liver microsomes were prepared using differential centrifugation and had activity on a par with the commercial preparations. This in vitro system metabolised the drugs and produced both phase I and II metabolites, similar to those observed in humans and horses in vivo. For example, the major metabolites of the benzodiazepine drug, diazepam, nordiazepam, temazepam and oxazepam as well as the glucuronidated phase II products were all found after incubations with the bovine liver microsomes. The metabolism of the drugs was also investigated in silico using the computational procedure, MetaSite. MetaSite was able to successfully predict known metabolites for most of the drugs studied. Differences were observed from the in vitro incubations and this is most likely due to MetaSite using only human cytochrome P450s for analysis.
- Full Text: