Developing a model for establishing, implementing, and maintaining learnerships in South Africa
- Authors: Hamlet, Brian
- Date: 2005
- Subjects: Employees -- Training of -- South Africa , Experiential learning -- South Africa , Education, Cooperative -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9377 , http://hdl.handle.net/10948/156 , Employees -- Training of -- South Africa , Experiential learning -- South Africa , Education, Cooperative -- South Africa
- Description: The research problem in this study was to identify how successful the methods are that organisations use within the Manufacturing Engineering and Related Services Education and Training Authorities (MERSETA) chambers to develop, implement and maintain learnerships. To achieve this aim a literature examination to determine the aspects of workplace learning were explored, including the various perspectives of learning, together with an investigation into workplace learning. Further, apprenticeships, traineeships, learnerships were discussed; including the concepts vocational education and training standards, and competence explored. Finally a process model for effective learnership implementation was presented based on international approaches together with the South African models and current practices. - v - The process learnership model served as a basis for drawing up a survey questionnaire to establish the extent to which organisations agreed or disagreed with the learnership model developed. The survey was limited to the “automobile” and “new tyre” chambers of the MERSETA. The results obtained from the empirical study indicted a high degree of agreement with the process model for effective learnership implementation. The results obtained from the quantitative data, and qualitative data were used to adapt the learnership process model, and produce a six-phase integrated learnership model. From the survey it become evident that organisations needed to be sensitised and educated as to learnerships before considering more seriously learnership implementation. Further, it emerged that learnerships cannot only be effective within a process approach, and that it should also take place within a positive “organisational learning culture”. Organisations and Sector Education and Training Authorities (SETAs) can now use the six-phase integrated learnership model with confidence, as there was a high degree of agreement with the learnership model that was developed as part of this research study. The six-phase integrated learnership model has been comprehensively developed and surveyed by organisations that are currently implementing learnerships on a large scale. Organisations and SETAs can now give effect to the Skills Development Act No. 97 of 1998, and contribute to the National skills Development Strategy of 2001, which aims to improve the workplace skills of all South Africans.
- Full Text:
- Date Issued: 2005
- Authors: Hamlet, Brian
- Date: 2005
- Subjects: Employees -- Training of -- South Africa , Experiential learning -- South Africa , Education, Cooperative -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9377 , http://hdl.handle.net/10948/156 , Employees -- Training of -- South Africa , Experiential learning -- South Africa , Education, Cooperative -- South Africa
- Description: The research problem in this study was to identify how successful the methods are that organisations use within the Manufacturing Engineering and Related Services Education and Training Authorities (MERSETA) chambers to develop, implement and maintain learnerships. To achieve this aim a literature examination to determine the aspects of workplace learning were explored, including the various perspectives of learning, together with an investigation into workplace learning. Further, apprenticeships, traineeships, learnerships were discussed; including the concepts vocational education and training standards, and competence explored. Finally a process model for effective learnership implementation was presented based on international approaches together with the South African models and current practices. - v - The process learnership model served as a basis for drawing up a survey questionnaire to establish the extent to which organisations agreed or disagreed with the learnership model developed. The survey was limited to the “automobile” and “new tyre” chambers of the MERSETA. The results obtained from the empirical study indicted a high degree of agreement with the process model for effective learnership implementation. The results obtained from the quantitative data, and qualitative data were used to adapt the learnership process model, and produce a six-phase integrated learnership model. From the survey it become evident that organisations needed to be sensitised and educated as to learnerships before considering more seriously learnership implementation. Further, it emerged that learnerships cannot only be effective within a process approach, and that it should also take place within a positive “organisational learning culture”. Organisations and Sector Education and Training Authorities (SETAs) can now use the six-phase integrated learnership model with confidence, as there was a high degree of agreement with the learnership model that was developed as part of this research study. The six-phase integrated learnership model has been comprehensively developed and surveyed by organisations that are currently implementing learnerships on a large scale. Organisations and SETAs can now give effect to the Skills Development Act No. 97 of 1998, and contribute to the National skills Development Strategy of 2001, which aims to improve the workplace skills of all South Africans.
- Full Text:
- Date Issued: 2005
Developing an environmental education strategy framework: a case study of the Endangered Wildlife Trust (EWT)
- Authors: O'Grady, Janis
- Date: 2005
- Subjects: Endangered Wildlife Trust Environmental education -- South Africa Conservation of natural resources -- South Africa Biodiversity -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1494 , http://hdl.handle.net/10962/d1003375
- Description: The study focused on the development of an environmental education (EE) strategy framework in the Endangered Wildlife Trust (EWT) of South Africa. Evidence shows that the roles of conservation and biodiversity education could potentially be merged towards producing a practical strategy, beneficial to the organisation and its individual staff members. Questionnaires, interviews and the individual perceptions of staff members, as well as the analysis of relevant documents, suggested that the potential for the practice of EE towards the development of an EE strategy within the organisation is substantial. EWT staff members can contribute towards a change in the way that South Africans think about conservation and nature. Environmental ethics need to be promoted and understood by all. Within the EWT, environmental education activities are in place and diverse, yet they lack any form of monitoring and evaluation. The Trust is already practicing a form of EE but the potential to do more and the opportunities for expansion are unlimited.
- Full Text:
- Date Issued: 2005
- Authors: O'Grady, Janis
- Date: 2005
- Subjects: Endangered Wildlife Trust Environmental education -- South Africa Conservation of natural resources -- South Africa Biodiversity -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1494 , http://hdl.handle.net/10962/d1003375
- Description: The study focused on the development of an environmental education (EE) strategy framework in the Endangered Wildlife Trust (EWT) of South Africa. Evidence shows that the roles of conservation and biodiversity education could potentially be merged towards producing a practical strategy, beneficial to the organisation and its individual staff members. Questionnaires, interviews and the individual perceptions of staff members, as well as the analysis of relevant documents, suggested that the potential for the practice of EE towards the development of an EE strategy within the organisation is substantial. EWT staff members can contribute towards a change in the way that South Africans think about conservation and nature. Environmental ethics need to be promoted and understood by all. Within the EWT, environmental education activities are in place and diverse, yet they lack any form of monitoring and evaluation. The Trust is already practicing a form of EE but the potential to do more and the opportunities for expansion are unlimited.
- Full Text:
- Date Issued: 2005
Developing strategies for creating an environmental focus in a school: narrating the change process
- Authors: Hope, Megan Samantha
- Date: 2005
- Subjects: Environmental education Educational change School environment
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1946 , http://hdl.handle.net/10962/d1008093
- Description: Effective environmental education goes beyond raising environmental awareness and developing positive environmental values, to the encouragement of personal responsibility and action in response to contextual environmental issues in particular. The whole school approach has been advocated as the best approach to environmental education, based on the assumption that the values and attitudes espoused in the classroom need to be reflected in the day-to-day school practice. By practising what they teach, schools reinforce values with action. In contrast, inconsistencies between the formal and non-formal curriculum may lead young people to question the integrity of their teachers or condition them to accept such inconsistencies as cultural and social norms, which in turn may lead to apathy about the environment. Adjustments to the ethos of a school to foreground the environment, both within the curriculum , the management of the school and the behaviour of teachers, pupils and support staff, is not a straightforward undertaking. Institutional factors influence the change process in schools and each school presents a unique context. It is, therefore, difficult to develop a general strategy for the evolution of an environmental ethos. This case study narrates an attempt to implement a change towards an improved environmental focus in a school, and focuses on developing an understanding of how available resources can assist this process while engaging with complexity of change.
- Full Text:
- Date Issued: 2005
- Authors: Hope, Megan Samantha
- Date: 2005
- Subjects: Environmental education Educational change School environment
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1946 , http://hdl.handle.net/10962/d1008093
- Description: Effective environmental education goes beyond raising environmental awareness and developing positive environmental values, to the encouragement of personal responsibility and action in response to contextual environmental issues in particular. The whole school approach has been advocated as the best approach to environmental education, based on the assumption that the values and attitudes espoused in the classroom need to be reflected in the day-to-day school practice. By practising what they teach, schools reinforce values with action. In contrast, inconsistencies between the formal and non-formal curriculum may lead young people to question the integrity of their teachers or condition them to accept such inconsistencies as cultural and social norms, which in turn may lead to apathy about the environment. Adjustments to the ethos of a school to foreground the environment, both within the curriculum , the management of the school and the behaviour of teachers, pupils and support staff, is not a straightforward undertaking. Institutional factors influence the change process in schools and each school presents a unique context. It is, therefore, difficult to develop a general strategy for the evolution of an environmental ethos. This case study narrates an attempt to implement a change towards an improved environmental focus in a school, and focuses on developing an understanding of how available resources can assist this process while engaging with complexity of change.
- Full Text:
- Date Issued: 2005
Development and analysis of a friction stir spot welding process for aluminium
- Authors: Stephen, Michael George
- Date: 2005
- Subjects: Friction welding , Electric welding , Aluminum alloys -- Welding
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9631 , http://hdl.handle.net/10948/1351 , Friction welding , Electric welding , Aluminum alloys -- Welding
- Description: Friction Stir Spot Welding (FSSW) has been developed from the conventional Friction Stir Welding (FSW) process, developed at The Welding Institute (TWI). FSSWs have been done without the keyhole being eliminated. Elimination of the keyhole would result in the process being more commercially viable. This dissertation focuses on an attempt of eliminating the keyhole using a retractable pin tool as well as a comparison of the weld integrity of a FSSW to that of a conventional Resistance Spot Weld (RSW). Welds were conducted on aluminium alloy 6063 T4. Comparisons between different weld procedures were done. Further analysis of the weld integrity between FSSW and RSW were conducted, comparing tensile strengths, microstructure and hardness. For the above welding procedure to take place, the current retractable pin tool, patented by PE Technikon, was redesigned. Problems associated during the welding process and the results obtained are documented. Reasons for the keyhole not being eliminated as well as recommendations for future work in the attempt to remove the keyhole are discussed.
- Full Text:
- Date Issued: 2005
- Authors: Stephen, Michael George
- Date: 2005
- Subjects: Friction welding , Electric welding , Aluminum alloys -- Welding
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9631 , http://hdl.handle.net/10948/1351 , Friction welding , Electric welding , Aluminum alloys -- Welding
- Description: Friction Stir Spot Welding (FSSW) has been developed from the conventional Friction Stir Welding (FSW) process, developed at The Welding Institute (TWI). FSSWs have been done without the keyhole being eliminated. Elimination of the keyhole would result in the process being more commercially viable. This dissertation focuses on an attempt of eliminating the keyhole using a retractable pin tool as well as a comparison of the weld integrity of a FSSW to that of a conventional Resistance Spot Weld (RSW). Welds were conducted on aluminium alloy 6063 T4. Comparisons between different weld procedures were done. Further analysis of the weld integrity between FSSW and RSW were conducted, comparing tensile strengths, microstructure and hardness. For the above welding procedure to take place, the current retractable pin tool, patented by PE Technikon, was redesigned. Problems associated during the welding process and the results obtained are documented. Reasons for the keyhole not being eliminated as well as recommendations for future work in the attempt to remove the keyhole are discussed.
- Full Text:
- Date Issued: 2005
Development and assessment of medicines information for antiretroviral therapy in Sub-Saharan Africa
- Authors: Mwingira, Betty
- Date: 2005
- Subjects: AIDS (Disease) -- Africa, Sub-Saharan , AIDS (Disease) -- Treatment -- Africa, Sub-Saharan , AIDS (Disease) -- Juvenile literature -- Africa, Sub-Saharan , HIV infections -- Treatment -- Africa, Sub-Saharan , HIV infections -- Africa, Sub-Saharan , Antiretroviral agents -- Africa, Sub-Saharan , HIV-positive persons -- Care -- Africa, Sub-Saharan , Hiv-positive persons -- Medical care -- Africa, Sub-Saharan , AIDS (Disease) -- Study and teaching -- Africa, Sub-Saharan
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3779 , http://hdl.handle.net/10962/d1003257 , AIDS (Disease) -- Africa, Sub-Saharan , AIDS (Disease) -- Treatment -- Africa, Sub-Saharan , AIDS (Disease) -- Juvenile literature -- Africa, Sub-Saharan , HIV infections -- Treatment -- Africa, Sub-Saharan , HIV infections -- Africa, Sub-Saharan , Antiretroviral agents -- Africa, Sub-Saharan , HIV-positive persons -- Care -- Africa, Sub-Saharan , Hiv-positive persons -- Medical care -- Africa, Sub-Saharan , AIDS (Disease) -- Study and teaching -- Africa, Sub-Saharan
- Full Text:
- Date Issued: 2005
Development and assessment of medicines information for antiretroviral therapy in Sub-Saharan Africa
- Authors: Mwingira, Betty
- Date: 2005
- Subjects: AIDS (Disease) -- Africa, Sub-Saharan , AIDS (Disease) -- Treatment -- Africa, Sub-Saharan , AIDS (Disease) -- Juvenile literature -- Africa, Sub-Saharan , HIV infections -- Treatment -- Africa, Sub-Saharan , HIV infections -- Africa, Sub-Saharan , Antiretroviral agents -- Africa, Sub-Saharan , HIV-positive persons -- Care -- Africa, Sub-Saharan , Hiv-positive persons -- Medical care -- Africa, Sub-Saharan , AIDS (Disease) -- Study and teaching -- Africa, Sub-Saharan
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3779 , http://hdl.handle.net/10962/d1003257 , AIDS (Disease) -- Africa, Sub-Saharan , AIDS (Disease) -- Treatment -- Africa, Sub-Saharan , AIDS (Disease) -- Juvenile literature -- Africa, Sub-Saharan , HIV infections -- Treatment -- Africa, Sub-Saharan , HIV infections -- Africa, Sub-Saharan , Antiretroviral agents -- Africa, Sub-Saharan , HIV-positive persons -- Care -- Africa, Sub-Saharan , Hiv-positive persons -- Medical care -- Africa, Sub-Saharan , AIDS (Disease) -- Study and teaching -- Africa, Sub-Saharan
- Full Text:
- Date Issued: 2005
Development of an experimental system to investigate the interaction between the Helicoverpa armigera stunt virus capsid protein and viral RNA
- Authors: Nel, Andrew James Mascré
- Date: 2005
- Subjects: Helicoverpa armigera , RNA viruses
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3946 , http://hdl.handle.net/10962/d1004005 , Helicoverpa armigera , RNA viruses
- Description: Tetraviruses are entomopathogenic viruses that propagate solely in lepidopteran hosts. Viruses of this group possess non-enveloped 38- to 40-nm capsids arranged in T = 4 surface symmetry. The viral genome consists of one or two single stranded positive sense RNA strands, which define the two genera of this family, the monopartite betatetraviruses and the bipartite omegatetraviruses. Two extensively studied members of the tetraviruses are the omegatetraviruses, Helicoverpa armigera stunt virus (HaSV) and the closely related Nudaurelia capensis ω virus (NωV). The larger genomic strand of HaSV (RNA1) encodes the viral replicase, while the other (RNA2) encodes the 71-kDa capsid precursor protein (p71). The pro-capsid is assembled from 240 copies of p71, which undergo a maturation auto-catalytic cleavage into the 64-kDa (p64) capsid protein and a 7-kDa peptide (p7) forming the capsid shell. The mechanism for the recognition and packaging of the viral genome is poorly understood for these viruses. The principle objective of the research described in this study was to develop in vitro and in vivo experimental systems to investigate interactions between the N terminal domain of HaSV p71 and viral RNAs. More specifically, the two positively charged clusters of predominantly arginine residues that are conserved amongst tetraviruses and the structurally analologous nodaviruses capsid protomers’ N terminal domains were investigated. An in vitro RNA-protein “pull down” system was developed using the rapid protein purification technique of the IMPACTTM-CN system. The coding sequence of the N terminal domain of p71 was fused to that of a chitin binding affinity tag (intein). This fusion protein was used as protein bait for the viral RNA. It was proposed that if RNA interacted with the fusion protein, it would be pulled down by the mass of affinity matrix and be precipitated and fluoresce when analysed by agarose gel electrophoresis using ethidium bromide. Despite optimisation of the in vitro assay, results were affected by the interaction between the intein-tag and nucleic acids, the state of the expressed fusion protein (in particular self-cleavage) and the excessive fluorescence present on the gels. The ADH2-GAPDH yeast expression system was used to investigate the in vivo assembly of p71 containing deletions of either one or both clusters within N terminal domain. It was found that all p71 mutants were expressed with the exception of the mutant containing a deletion of the second cluster. The reasons for this still require further investigation. The expressed p71 mutants were not processed into p64 and were degraded in vivo. In addition, an experimental attempt to purify assembled p71 mutant VLPs was unsuccessful. The assembly defect of p71 mutants emphasised the significance of the clusters, which are possibly required for interaction with viral RNAs for efficient VLP assembly. The results of this study suggest that an alternative tag or in vitro RNA-protein interaction assay be used. In addition, further experiments are required to investigate whether the co-expression of full length viral RNAs are required to rescue the in vivo assembly defect of p71 mutants into VLPs.
- Full Text:
- Date Issued: 2005
- Authors: Nel, Andrew James Mascré
- Date: 2005
- Subjects: Helicoverpa armigera , RNA viruses
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3946 , http://hdl.handle.net/10962/d1004005 , Helicoverpa armigera , RNA viruses
- Description: Tetraviruses are entomopathogenic viruses that propagate solely in lepidopteran hosts. Viruses of this group possess non-enveloped 38- to 40-nm capsids arranged in T = 4 surface symmetry. The viral genome consists of one or two single stranded positive sense RNA strands, which define the two genera of this family, the monopartite betatetraviruses and the bipartite omegatetraviruses. Two extensively studied members of the tetraviruses are the omegatetraviruses, Helicoverpa armigera stunt virus (HaSV) and the closely related Nudaurelia capensis ω virus (NωV). The larger genomic strand of HaSV (RNA1) encodes the viral replicase, while the other (RNA2) encodes the 71-kDa capsid precursor protein (p71). The pro-capsid is assembled from 240 copies of p71, which undergo a maturation auto-catalytic cleavage into the 64-kDa (p64) capsid protein and a 7-kDa peptide (p7) forming the capsid shell. The mechanism for the recognition and packaging of the viral genome is poorly understood for these viruses. The principle objective of the research described in this study was to develop in vitro and in vivo experimental systems to investigate interactions between the N terminal domain of HaSV p71 and viral RNAs. More specifically, the two positively charged clusters of predominantly arginine residues that are conserved amongst tetraviruses and the structurally analologous nodaviruses capsid protomers’ N terminal domains were investigated. An in vitro RNA-protein “pull down” system was developed using the rapid protein purification technique of the IMPACTTM-CN system. The coding sequence of the N terminal domain of p71 was fused to that of a chitin binding affinity tag (intein). This fusion protein was used as protein bait for the viral RNA. It was proposed that if RNA interacted with the fusion protein, it would be pulled down by the mass of affinity matrix and be precipitated and fluoresce when analysed by agarose gel electrophoresis using ethidium bromide. Despite optimisation of the in vitro assay, results were affected by the interaction between the intein-tag and nucleic acids, the state of the expressed fusion protein (in particular self-cleavage) and the excessive fluorescence present on the gels. The ADH2-GAPDH yeast expression system was used to investigate the in vivo assembly of p71 containing deletions of either one or both clusters within N terminal domain. It was found that all p71 mutants were expressed with the exception of the mutant containing a deletion of the second cluster. The reasons for this still require further investigation. The expressed p71 mutants were not processed into p64 and were degraded in vivo. In addition, an experimental attempt to purify assembled p71 mutant VLPs was unsuccessful. The assembly defect of p71 mutants emphasised the significance of the clusters, which are possibly required for interaction with viral RNAs for efficient VLP assembly. The results of this study suggest that an alternative tag or in vitro RNA-protein interaction assay be used. In addition, further experiments are required to investigate whether the co-expression of full length viral RNAs are required to rescue the in vivo assembly defect of p71 mutants into VLPs.
- Full Text:
- Date Issued: 2005
Development of experimental systems for studying the biology of Nudaurelia capensis ß virus
- Authors: Walter, Cheryl Tracy
- Date: 2005
- Subjects: Imbrasia cytherea , Insects -- Viruses , RNA viruses , DNA
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3948 , http://hdl.handle.net/10962/d1004007 , Imbrasia cytherea , Insects -- Viruses , RNA viruses , DNA
- Description: After 20 years, Nudaurelia ß virus (NßV) was re-isolated from a population of Nudaurelia capensis larvae exhibiting similar symptoms to those described in 1974 for a tetravirus infection. NßV is a member of the Tetraviridae, a family of positive sense insect RNA viruses that exclusively infect Lepidopteran insects. In addition to NbV, there was evidence that the insects were infected with another small RNA virus. SDS-PAGE and Western analysis revealed two proteins (p56 and p58), that cross-reacted with anti-NbV antibodies. Transmission Electron Microscopy (TEM) analysis showed the presence of particles exhibiting a morphology described for NbV and majority of particles of a diameter of 37 nm. In addition there was a second, minor population of particles with a diameter of 34 nm, which also exhibited the characteristic pitted surface of NßV, raising the possibility of two species of NßV in the N. capensis population. To further investigate this, cDNA corresponding to the 3` end of the replicase gene as well as the entire capsid gene of NbV was synthesized and sequenced. Alignments of the cDNA sequence showed a 99.46 % identity to the published sequence of NbV. Two amino acid substitutions were observed in the capsid coding sequence, one of which was a conservative substitution. Both of these substitutions were found in the b-sandwich domain of the capsid protein. Inspection of the capsid coding sequence showed a second methionine (Met50) at the VCAP amino terminus raising the possibility that p56 might arise from a translation product starting at this site. To investigate this, a full length and truncated capsid coding sequence starting at Met50, were expressed in a baculovirus expression system. VLPs were examined by TEM and Western analysis showed the presence of virus like particles with NßV morphology, but smaller in diameter than the wild-type with an average of 33.33 nm, similar to the smaller particles observed in the virus preparations of NßV. This result supported the hypothesis that NßV translates a smaller coat protein from the second in-frame methionine residue.
- Full Text:
- Date Issued: 2005
- Authors: Walter, Cheryl Tracy
- Date: 2005
- Subjects: Imbrasia cytherea , Insects -- Viruses , RNA viruses , DNA
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3948 , http://hdl.handle.net/10962/d1004007 , Imbrasia cytherea , Insects -- Viruses , RNA viruses , DNA
- Description: After 20 years, Nudaurelia ß virus (NßV) was re-isolated from a population of Nudaurelia capensis larvae exhibiting similar symptoms to those described in 1974 for a tetravirus infection. NßV is a member of the Tetraviridae, a family of positive sense insect RNA viruses that exclusively infect Lepidopteran insects. In addition to NbV, there was evidence that the insects were infected with another small RNA virus. SDS-PAGE and Western analysis revealed two proteins (p56 and p58), that cross-reacted with anti-NbV antibodies. Transmission Electron Microscopy (TEM) analysis showed the presence of particles exhibiting a morphology described for NbV and majority of particles of a diameter of 37 nm. In addition there was a second, minor population of particles with a diameter of 34 nm, which also exhibited the characteristic pitted surface of NßV, raising the possibility of two species of NßV in the N. capensis population. To further investigate this, cDNA corresponding to the 3` end of the replicase gene as well as the entire capsid gene of NbV was synthesized and sequenced. Alignments of the cDNA sequence showed a 99.46 % identity to the published sequence of NbV. Two amino acid substitutions were observed in the capsid coding sequence, one of which was a conservative substitution. Both of these substitutions were found in the b-sandwich domain of the capsid protein. Inspection of the capsid coding sequence showed a second methionine (Met50) at the VCAP amino terminus raising the possibility that p56 might arise from a translation product starting at this site. To investigate this, a full length and truncated capsid coding sequence starting at Met50, were expressed in a baculovirus expression system. VLPs were examined by TEM and Western analysis showed the presence of virus like particles with NßV morphology, but smaller in diameter than the wild-type with an average of 33.33 nm, similar to the smaller particles observed in the virus preparations of NßV. This result supported the hypothesis that NßV translates a smaller coat protein from the second in-frame methionine residue.
- Full Text:
- Date Issued: 2005
Development of the South African monetary banking sector and money market
- Authors: Patel, Aadil Suleman
- Date: 2005
- Subjects: South African Reserve Bank , Banks and banking -- South Africa , Money market -- South Africa , Economic development -- South Africa , Monetary policy -- South Africa , South Africa -- Economic conditions , Financial institutions -- South Africa , Money -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:997 , http://hdl.handle.net/10962/d1002732 , South African Reserve Bank , Banks and banking -- South Africa , Money market -- South Africa , Economic development -- South Africa , Monetary policy -- South Africa , South Africa -- Economic conditions , Financial institutions -- South Africa , Money -- South Africa
- Description: This thesis presents a theoretical analysis of developments in the South African monetary banking sector and money market. In the first section, evolution of the political, social and economic environments over the past few decades are discussed to provide the reader with an idea of some factors responsible for the underdeveloped nature of this market. It has been argued that the domestic political and economic landscape is relatively stable. Nevertheless, factors such as Zimbabwe’s political and ensuing economic turmoil, coupled with numerous financial crises in other developing nations have had negative consequences on domestic financial market development and economic growth. The current state of monetary policy is also analysed, within the economic environment, and various policy considerations have been put forth concerning the inflation targeting policy. The thesis then goes on to scrutinise the statutory and institutional environments within which the monetary banking institutions operate. Recent changes in the regulations governing the operations of these institutions are identified, together with the consequences of such laws on banking institutions and possible amendments have been suggested. In particular, a system of Asset Based Reserve Requirements (ABRR) has been recommended, in place of the current cash reserve requirement, to ensure regulators create a level playing field in the financial sector. The system can also provide authorities with the necessary control required to direct funds to the most desirable sectors of the economy. Development of the interbank market and the effect of reduced banking competition on the efficacy of the South African Reserve Bank’s refinancing operations and inflation targeting policy are also considered. Finally, the thesis analyses some effects of financial development on the South African economy, and whether it is in the best interests of the country to pursue financial reforms with such vigour. While financial development may bring South Africa closer to international standards of best practice, the timing and extent of the reforms will be critical to guarantee success.
- Full Text:
- Date Issued: 2005
- Authors: Patel, Aadil Suleman
- Date: 2005
- Subjects: South African Reserve Bank , Banks and banking -- South Africa , Money market -- South Africa , Economic development -- South Africa , Monetary policy -- South Africa , South Africa -- Economic conditions , Financial institutions -- South Africa , Money -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:997 , http://hdl.handle.net/10962/d1002732 , South African Reserve Bank , Banks and banking -- South Africa , Money market -- South Africa , Economic development -- South Africa , Monetary policy -- South Africa , South Africa -- Economic conditions , Financial institutions -- South Africa , Money -- South Africa
- Description: This thesis presents a theoretical analysis of developments in the South African monetary banking sector and money market. In the first section, evolution of the political, social and economic environments over the past few decades are discussed to provide the reader with an idea of some factors responsible for the underdeveloped nature of this market. It has been argued that the domestic political and economic landscape is relatively stable. Nevertheless, factors such as Zimbabwe’s political and ensuing economic turmoil, coupled with numerous financial crises in other developing nations have had negative consequences on domestic financial market development and economic growth. The current state of monetary policy is also analysed, within the economic environment, and various policy considerations have been put forth concerning the inflation targeting policy. The thesis then goes on to scrutinise the statutory and institutional environments within which the monetary banking institutions operate. Recent changes in the regulations governing the operations of these institutions are identified, together with the consequences of such laws on banking institutions and possible amendments have been suggested. In particular, a system of Asset Based Reserve Requirements (ABRR) has been recommended, in place of the current cash reserve requirement, to ensure regulators create a level playing field in the financial sector. The system can also provide authorities with the necessary control required to direct funds to the most desirable sectors of the economy. Development of the interbank market and the effect of reduced banking competition on the efficacy of the South African Reserve Bank’s refinancing operations and inflation targeting policy are also considered. Finally, the thesis analyses some effects of financial development on the South African economy, and whether it is in the best interests of the country to pursue financial reforms with such vigour. While financial development may bring South Africa closer to international standards of best practice, the timing and extent of the reforms will be critical to guarantee success.
- Full Text:
- Date Issued: 2005
Diet and daily ration of two nototheniid fish on the shelf of the sub-Antarctic Prince Edward Islands
- Bushula, T, Pakhomov, Evgeny A, Kaehler, Sven, Davis, S, Kalin, R M
- Authors: Bushula, T , Pakhomov, Evgeny A , Kaehler, Sven , Davis, S , Kalin, R M
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6948 , http://hdl.handle.net/10962/d1011977
- Description: The seasonal dietary composition and estimates of daily consumption rate of Lepidonotothen larseni and Gobionotothen marionensis juveniles were obtained for the first time using fish collected near sub-Antarctic Prince Edward Islands during April 1999–2003. The diet of L. larseni consisted mainly of pelagic prey, with copepods and arrow worms making up the most significant prey groups and accounting for 46% and 40% of prey mass, respectively. The diet of G. marionensis was more diverse than that of L. larseni and was composed mainly of benthic prey, including bottom-dwelling decapods (Nauticaris marionis) and sedentary polychaetes, which accounted for 54% and 30% of prey mass, respectively. During the present study, dietary overlap between juveniles of L. larseni and G. marionensis was very low (<5%) indicating that competition for food resources between them was negligible. They not only relied on different prey species, both also exhibited different diel feeding regimes. Daily consumption rate of L. larseni and G. marionensis juveniles was estimated to be 4.5% and 5.2% of body dry mass, respectively. Stomach contents and stable isotope analyses suggested, that both L. larseni and G. marionensis occupy the forth-trophic level of the sub-Antarctic food web but depend mainly on allochthonous and autochthonous (kelp derived) organic matter, respectively.
- Full Text:
- Date Issued: 2005
- Authors: Bushula, T , Pakhomov, Evgeny A , Kaehler, Sven , Davis, S , Kalin, R M
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6948 , http://hdl.handle.net/10962/d1011977
- Description: The seasonal dietary composition and estimates of daily consumption rate of Lepidonotothen larseni and Gobionotothen marionensis juveniles were obtained for the first time using fish collected near sub-Antarctic Prince Edward Islands during April 1999–2003. The diet of L. larseni consisted mainly of pelagic prey, with copepods and arrow worms making up the most significant prey groups and accounting for 46% and 40% of prey mass, respectively. The diet of G. marionensis was more diverse than that of L. larseni and was composed mainly of benthic prey, including bottom-dwelling decapods (Nauticaris marionis) and sedentary polychaetes, which accounted for 54% and 30% of prey mass, respectively. During the present study, dietary overlap between juveniles of L. larseni and G. marionensis was very low (<5%) indicating that competition for food resources between them was negligible. They not only relied on different prey species, both also exhibited different diel feeding regimes. Daily consumption rate of L. larseni and G. marionensis juveniles was estimated to be 4.5% and 5.2% of body dry mass, respectively. Stomach contents and stable isotope analyses suggested, that both L. larseni and G. marionensis occupy the forth-trophic level of the sub-Antarctic food web but depend mainly on allochthonous and autochthonous (kelp derived) organic matter, respectively.
- Full Text:
- Date Issued: 2005
Dimensions of guest house service: perceptions of owners and expectations of business travellers
- Wang, Yi
- Authors: Wang, Yi
- Date: 2005
- Subjects: Hospitality industry -- Customer relations , Boardinghouses -- Customer services -- South Africa , Consumer satisfaction -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9354 , http://hdl.handle.net/10948/d1006215 , Hospitality industry -- Customer relations , Boardinghouses -- Customer services -- South Africa , Consumer satisfaction -- South Africa
- Description: The need for successful management of a guest house in the increasingly competitive hospitality industry in South Africa, compels guest house owners to understand their customers’ needs and deliver service of acceptable quality. The objective of the research is to find out what business travellers expect from a guest house and how these expectations compare with the perceptions of guest house owners in Port Elizabeth. Conclusions drawn from this research would also benefit guest house owners in other parts of the country. A literature review was conducted to provide an understanding of the nature of service and the role “evidence of service” can play in the perception of quality. The empirical study aimed at comparing business travellers’ expectations of guest house service with guest house owners’ perceptions of their guests’ expectations. The empirical findings showed that business travellers deemed secure parking and professionalism of staff as the most important attributes, while guest house owners thought it would be friendliness of front desk staff and efficient handling of complaints. Moreover, both groups indicated that cleanliness of rooms and services performed by staff adequately the first time, were of particular importance. It was also found that the importance rating of the different service dimensions were not significantly influenced by the business travellers’ gender, managerial position, nights of stay or by the guest house grading. The study proposes that guest house owners continue to focus on strategies for training and developing competent employees, simplify the steps of service delivery and improve on the standards of the servcie to ensure that business facilities are in line with the expectations of business travelers.
- Full Text:
- Date Issued: 2005
- Authors: Wang, Yi
- Date: 2005
- Subjects: Hospitality industry -- Customer relations , Boardinghouses -- Customer services -- South Africa , Consumer satisfaction -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9354 , http://hdl.handle.net/10948/d1006215 , Hospitality industry -- Customer relations , Boardinghouses -- Customer services -- South Africa , Consumer satisfaction -- South Africa
- Description: The need for successful management of a guest house in the increasingly competitive hospitality industry in South Africa, compels guest house owners to understand their customers’ needs and deliver service of acceptable quality. The objective of the research is to find out what business travellers expect from a guest house and how these expectations compare with the perceptions of guest house owners in Port Elizabeth. Conclusions drawn from this research would also benefit guest house owners in other parts of the country. A literature review was conducted to provide an understanding of the nature of service and the role “evidence of service” can play in the perception of quality. The empirical study aimed at comparing business travellers’ expectations of guest house service with guest house owners’ perceptions of their guests’ expectations. The empirical findings showed that business travellers deemed secure parking and professionalism of staff as the most important attributes, while guest house owners thought it would be friendliness of front desk staff and efficient handling of complaints. Moreover, both groups indicated that cleanliness of rooms and services performed by staff adequately the first time, were of particular importance. It was also found that the importance rating of the different service dimensions were not significantly influenced by the business travellers’ gender, managerial position, nights of stay or by the guest house grading. The study proposes that guest house owners continue to focus on strategies for training and developing competent employees, simplify the steps of service delivery and improve on the standards of the servcie to ensure that business facilities are in line with the expectations of business travelers.
- Full Text:
- Date Issued: 2005
Discourses surrounding 'race', equity, disadvantage and transformation in times of rapid social change : higher education in post-apartheid South Africa
- Authors: Robus, Donovan
- Date: 2005
- Subjects: Rhodes University , University of Fort Hare , Universities and colleges -- Mergers -- South Africa , Education, Higher -- South Africa , Education and state -- South Africa , Apartheid -- South Africa , Discourse analysis -- Methodology , Discrimination in education -- South Africa , Educational change -- South Africa
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3142 , http://hdl.handle.net/10962/d1007196 , Rhodes University , University of Fort Hare , Universities and colleges -- Mergers -- South Africa , Education, Higher -- South Africa , Education and state -- South Africa , Apartheid -- South Africa , Discourse analysis -- Methodology , Discrimination in education -- South Africa , Educational change -- South Africa
- Description: Since the dismantling of Apartheid in South Africa in 1994, the South African socio-political and economic landscape has been characterised by rapid change. In the ten years since the 'new' democratic South Africa emerged, transformation has become a dominant discourse that has driven much action and practice in a variety of public areas. One of the areas of focus for transformation has been Higher Education whereby the Department of Education aimed to do away with disparity caused by Apartheid segregation by reducing the number of Higher Education institutions from 36 to 21. This research draws on Foucauldian theory and post-colonial theories (in particular Edward Said and Frantz Fanon), and the concept of racialisation in an analysis of the incorporation of Rhodes University's East London campus into the University of Fort Hare. Ian Parker's discourse analytic approach which suggests that discourses support institutions, reproduce power relations and have ideological effects, was utilised to analyse the talk of students and staff at the three sites affected by the incorporation (viz. Rhodes, Grahamstown, Rhodes, East London and Fort Hare) as well as newspaper articles and public statements made by the two institutions. What emerged was that in post-Apartheid South Africa, institutional and geographic space is still racialised with virtually no reference to the historical and contextual foundations from which this emerged being made. In positioning space and institutions in this racialised manner a discourse of 'white' excellence and 'black' failure emerges with the notion of competence gaining legitimacy through an appeal to academic standards. In addition to this, transformation emerges as a signifier of shifting boundaries in a post-Apartheid society where racialised institutional, spatial and social boundaries evidently still exist discursively.
- Full Text:
- Date Issued: 2005
- Authors: Robus, Donovan
- Date: 2005
- Subjects: Rhodes University , University of Fort Hare , Universities and colleges -- Mergers -- South Africa , Education, Higher -- South Africa , Education and state -- South Africa , Apartheid -- South Africa , Discourse analysis -- Methodology , Discrimination in education -- South Africa , Educational change -- South Africa
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3142 , http://hdl.handle.net/10962/d1007196 , Rhodes University , University of Fort Hare , Universities and colleges -- Mergers -- South Africa , Education, Higher -- South Africa , Education and state -- South Africa , Apartheid -- South Africa , Discourse analysis -- Methodology , Discrimination in education -- South Africa , Educational change -- South Africa
- Description: Since the dismantling of Apartheid in South Africa in 1994, the South African socio-political and economic landscape has been characterised by rapid change. In the ten years since the 'new' democratic South Africa emerged, transformation has become a dominant discourse that has driven much action and practice in a variety of public areas. One of the areas of focus for transformation has been Higher Education whereby the Department of Education aimed to do away with disparity caused by Apartheid segregation by reducing the number of Higher Education institutions from 36 to 21. This research draws on Foucauldian theory and post-colonial theories (in particular Edward Said and Frantz Fanon), and the concept of racialisation in an analysis of the incorporation of Rhodes University's East London campus into the University of Fort Hare. Ian Parker's discourse analytic approach which suggests that discourses support institutions, reproduce power relations and have ideological effects, was utilised to analyse the talk of students and staff at the three sites affected by the incorporation (viz. Rhodes, Grahamstown, Rhodes, East London and Fort Hare) as well as newspaper articles and public statements made by the two institutions. What emerged was that in post-Apartheid South Africa, institutional and geographic space is still racialised with virtually no reference to the historical and contextual foundations from which this emerged being made. In positioning space and institutions in this racialised manner a discourse of 'white' excellence and 'black' failure emerges with the notion of competence gaining legitimacy through an appeal to academic standards. In addition to this, transformation emerges as a signifier of shifting boundaries in a post-Apartheid society where racialised institutional, spatial and social boundaries evidently still exist discursively.
- Full Text:
- Date Issued: 2005
Draft Gender Indicators
- COSATU
- Authors: COSATU
- Date: 2005
- Subjects: COSATU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/172109 , vital:42160
- Description: Women in both the trade union movement and the formal work environment face obstacles which inhibit the progress of their concerns. Despite a range of gender resolutions passed at trade union congresses and the equality clauses inherent in the constitution and labour legislation, issues of particular concern to women are not mainstreamed in trade union negotiations. In instances where issues such as maternity benefits are fully integrated, women workers may still face difficult choices when it comes to ensuring that rights and labour laws are adhered to in the workplace. Many women workers often find that their position at work has been changed while they have been off on maternity leave, or they have been included in a retrenchment negotiation while away. An important question to ask in building a framework of gender indicators for collective bargaining, are what are the obstacles in trade unions which inhibit women’s active participation in collective bargaining?
- Full Text:
- Date Issued: 2005
- Authors: COSATU
- Date: 2005
- Subjects: COSATU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/172109 , vital:42160
- Description: Women in both the trade union movement and the formal work environment face obstacles which inhibit the progress of their concerns. Despite a range of gender resolutions passed at trade union congresses and the equality clauses inherent in the constitution and labour legislation, issues of particular concern to women are not mainstreamed in trade union negotiations. In instances where issues such as maternity benefits are fully integrated, women workers may still face difficult choices when it comes to ensuring that rights and labour laws are adhered to in the workplace. Many women workers often find that their position at work has been changed while they have been off on maternity leave, or they have been included in a retrenchment negotiation while away. An important question to ask in building a framework of gender indicators for collective bargaining, are what are the obstacles in trade unions which inhibit women’s active participation in collective bargaining?
- Full Text:
- Date Issued: 2005
Duress in the Roman-Dutch law of obligations
- Authors: Glover, Graham B
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6337 , http://hdl.handle.net/10962/d1012402
- Description: [From the introduction]: The institutional writers and practitioners of 16th, 17th and 18th century Roman- Dutch law looked to the Roman law of obligations to form the foundation upon which they erected their structure of private law. During the course of the reception, the idea was that Roman law was supposed to be referred to and applied only where the indigenous law did not already cater for a legal problem.
- Full Text:
- Date Issued: 2005
- Authors: Glover, Graham B
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6337 , http://hdl.handle.net/10962/d1012402
- Description: [From the introduction]: The institutional writers and practitioners of 16th, 17th and 18th century Roman- Dutch law looked to the Roman law of obligations to form the foundation upon which they erected their structure of private law. During the course of the reception, the idea was that Roman law was supposed to be referred to and applied only where the indigenous law did not already cater for a legal problem.
- Full Text:
- Date Issued: 2005
Effective management of an information technology professional's career
- Authors: Tedder, Derek
- Date: 2005
- Subjects: Information technology -- Vocational guidance , Information technology -- Management , Knowledge management , Career development , Computer Science -- Vocational guidance , System analysis -- Vocational guidance
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1148 , http://hdl.handle.net/10962/d1004543 , Information technology -- Vocational guidance , Information technology -- Management , Knowledge management , Career development , Computer Science -- Vocational guidance , System analysis -- Vocational guidance
- Description: The human resource is constantly cited as an organisation's greatest asset. In a rapidly changing technological environment this is most applicable to the Information Technology (IT) function. Organisations are experiencing IT human resource problems such as low satisfaction, early plateauing, high turnover, burnout, limited advancement potential, nominal corporate commitment, supervisory aversion, poor organisational culture, and exceptional compensation. These problems are directly related to the IT professional's career. There is a lack of information and awareness surrounding IT careers to deal effectively with these problems. The research aims to create increased awareness of IT careers and the inherent problems through the development of a career management model. The research aims to identify the factors that influence IT careers, provide career management with a means to measure compatibility of the factors, and suggest solutions to incompatibility. The solving of this problem will be of mutual benefit to both organisations and individuals as they seek to better manage IT careers. After reviewing research literature relating to career anchors, IT job types, IT skills portfolios, and career dynamics a model for Effective IT Career Management (EITCM) has been constructed. The model represents the dynamic interactions between individual, organisational, and dependent factors. The model examines the compatibility of these interacting factors by measuring the levels of relevant career variables. The model suggests appropriate career management techniques to increase the compatibility of the interacting factors. An empirical study was designed and launched online to provide data that would confirm the seven Critical Success Factors (CSF) relating to the proposed model. The responses from the members of the Computer Society of South Africa (CSSA) allowed the seven hypotheses derived from the CSFs to be tested. The results of the empirical study were positive but required modification to five of the CSFs before they could be confirmed. The EITCM model was modified to reflect the improved CSFs. An awareness of career influencing factors combined with active career management is advantageous to both IT professionals and their organisations.
- Full Text:
- Date Issued: 2005
- Authors: Tedder, Derek
- Date: 2005
- Subjects: Information technology -- Vocational guidance , Information technology -- Management , Knowledge management , Career development , Computer Science -- Vocational guidance , System analysis -- Vocational guidance
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1148 , http://hdl.handle.net/10962/d1004543 , Information technology -- Vocational guidance , Information technology -- Management , Knowledge management , Career development , Computer Science -- Vocational guidance , System analysis -- Vocational guidance
- Description: The human resource is constantly cited as an organisation's greatest asset. In a rapidly changing technological environment this is most applicable to the Information Technology (IT) function. Organisations are experiencing IT human resource problems such as low satisfaction, early plateauing, high turnover, burnout, limited advancement potential, nominal corporate commitment, supervisory aversion, poor organisational culture, and exceptional compensation. These problems are directly related to the IT professional's career. There is a lack of information and awareness surrounding IT careers to deal effectively with these problems. The research aims to create increased awareness of IT careers and the inherent problems through the development of a career management model. The research aims to identify the factors that influence IT careers, provide career management with a means to measure compatibility of the factors, and suggest solutions to incompatibility. The solving of this problem will be of mutual benefit to both organisations and individuals as they seek to better manage IT careers. After reviewing research literature relating to career anchors, IT job types, IT skills portfolios, and career dynamics a model for Effective IT Career Management (EITCM) has been constructed. The model represents the dynamic interactions between individual, organisational, and dependent factors. The model examines the compatibility of these interacting factors by measuring the levels of relevant career variables. The model suggests appropriate career management techniques to increase the compatibility of the interacting factors. An empirical study was designed and launched online to provide data that would confirm the seven Critical Success Factors (CSF) relating to the proposed model. The responses from the members of the Computer Society of South Africa (CSSA) allowed the seven hypotheses derived from the CSFs to be tested. The results of the empirical study were positive but required modification to five of the CSFs before they could be confirmed. The EITCM model was modified to reflect the improved CSFs. An awareness of career influencing factors combined with active career management is advantageous to both IT professionals and their organisations.
- Full Text:
- Date Issued: 2005
Effects of central metal on the photophysical and photochemical properties of non-transition metal sulfophthalocyanine
- Ogunsipe, Abimbola, Nyokong, Tebello
- Authors: Ogunsipe, Abimbola , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289337 , vital:56623 , xlink:href="https://doi.org/10.1142/S1088424605000186"
- Description: The photophysical and photochemical properties and quenching (by 1,4-benzoquinone) of metallophthalocyanine sulfonates of aluminium (AlPcSmix), zinc (ZnPcSmix), silicon (SiPcSmix), germanium (GePcSmix) and tin (SnPcSmix) are presented. The quantum yield values of fluorescence (ΦF), triplet state (ΦT), singlet oxygen (ΦΔ) and photodegradation (Φd) were determined and the observed trends in their variation among the complexes discussed in terms of aggregation and the heavy atom effect. 1,4-benzoquinone effectively quenched the fluorescence of the complexes. Quenching analyses gave positive deviations from Stern-Volmer behavior, suggesting the existence of static quenching in addition to dynamic quenching. The static and dynamic components of the quenching were separated using a modified Stern-Volmer equation and the “sphere of action quenching model”. The quenching constant was found to be a function of the radius of the central metal ion.
- Full Text:
- Date Issued: 2005
- Authors: Ogunsipe, Abimbola , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289337 , vital:56623 , xlink:href="https://doi.org/10.1142/S1088424605000186"
- Description: The photophysical and photochemical properties and quenching (by 1,4-benzoquinone) of metallophthalocyanine sulfonates of aluminium (AlPcSmix), zinc (ZnPcSmix), silicon (SiPcSmix), germanium (GePcSmix) and tin (SnPcSmix) are presented. The quantum yield values of fluorescence (ΦF), triplet state (ΦT), singlet oxygen (ΦΔ) and photodegradation (Φd) were determined and the observed trends in their variation among the complexes discussed in terms of aggregation and the heavy atom effect. 1,4-benzoquinone effectively quenched the fluorescence of the complexes. Quenching analyses gave positive deviations from Stern-Volmer behavior, suggesting the existence of static quenching in addition to dynamic quenching. The static and dynamic components of the quenching were separated using a modified Stern-Volmer equation and the “sphere of action quenching model”. The quenching constant was found to be a function of the radius of the central metal ion.
- Full Text:
- Date Issued: 2005
Electro-oxidation of phenol and its derivatives on poly-Ni (OH) TPhPyPc modified vitreous carbon electrodes
- Obirai, Joseph, Bedioui, Fethi, Nyokong, Tebello
- Authors: Obirai, Joseph , Bedioui, Fethi , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289353 , vital:56625 , xlink:href="https://doi.org/10.1016/j.jelechem.2004.11.006"
- Description: The electrochemical oxidation of phenol and its derivatives using poly-nickel hydroxy tetraphenoxypyrrolephthalocyanine (poly-Ni(OH)TPhPyPc) modified vitreous carbon electrodes are described. The films were formed by the electro-transformation of the electropolymerized pyrrole-substituted phenoxyphthalocyanine poly-NiTPhPyPc modified electrode in aqueous 0.1 M NaOH solution. The poly-Ni(OH)TPhPyPc films showed better stability and resistance to electrode fouling compared to poly-NiTPhPyPc and unmodified electrodes. The resistance to surface fouling and stability can be attributed to the structure of the ring substituent on the phthalocyanine macrocycle and to the particular O–Ni–O bridged architecture of the nickel phthalocyanine film.
- Full Text:
- Date Issued: 2005
- Authors: Obirai, Joseph , Bedioui, Fethi , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289353 , vital:56625 , xlink:href="https://doi.org/10.1016/j.jelechem.2004.11.006"
- Description: The electrochemical oxidation of phenol and its derivatives using poly-nickel hydroxy tetraphenoxypyrrolephthalocyanine (poly-Ni(OH)TPhPyPc) modified vitreous carbon electrodes are described. The films were formed by the electro-transformation of the electropolymerized pyrrole-substituted phenoxyphthalocyanine poly-NiTPhPyPc modified electrode in aqueous 0.1 M NaOH solution. The poly-Ni(OH)TPhPyPc films showed better stability and resistance to electrode fouling compared to poly-NiTPhPyPc and unmodified electrodes. The resistance to surface fouling and stability can be attributed to the structure of the ring substituent on the phthalocyanine macrocycle and to the particular O–Ni–O bridged architecture of the nickel phthalocyanine film.
- Full Text:
- Date Issued: 2005
Electrocatalytic oxidation and detection of hydrazine at gold electrode modified with iron phthalocyanine complex linked to mercaptopyridine self-assembled monolayer
- Ozoemena, Kenneth I, Nyokong, Tebello
- Authors: Ozoemena, Kenneth I , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/286065 , vital:56235 , xlink:href="https://doi.org/10.1016/j.talanta.2005.02.030"
- Description: Electrocatalytic oxidation and detection of hydrazine in pH 7.0 conditions were studied by using gold electrode modified with self-assembled monolayer (SAM) films of iron phthalocyanine (FePc) complex axially ligated to a preformed 4-mercaptopyridine SAMs. The anodic oxidation of hydrazine in neutral pH conditions with FePc-linked-mercaptopyridine-SAM-modified gold electrode occurred at low overpotential (0.35 V versus Ag|AgCl) and the treatment of the voltammetric data showed that it was a pure diffusion-controlled reaction with the involvement of one electron in the rate-determining step. The mechanism for the interaction of hydrazine with the FePc-SAM is proposed to involve the Fe(III)Pc/Fe(II)Pc redox process. Using cyclic voltammetry (CV) and Osteryoung square wave voltammetry (OSWV), hydrazine was detected over a linear concentration range of 1.3 × 10−5 to 9.2 × 10−5 mol/L with low limits of detection (ca. 5 and 11 μM for OSWV and CV, respectively). At concentrations higher than 1.2 × 10−4 mol/L the anodic peak potential shifted to 0.40 V (versus Ag|AgCl), and this was interpreted to be due to kinetic limitations resulting from the saturation of hydrazine and its oxidation products onto the redox-active monolayer film. This type of metallophthalocyanine-SAM-based electrode is a highly promising electrochemical sensor given its ease of fabrication, good catalytic activity, stability, sensitivity and simplicity.
- Full Text:
- Date Issued: 2005
- Authors: Ozoemena, Kenneth I , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/286065 , vital:56235 , xlink:href="https://doi.org/10.1016/j.talanta.2005.02.030"
- Description: Electrocatalytic oxidation and detection of hydrazine in pH 7.0 conditions were studied by using gold electrode modified with self-assembled monolayer (SAM) films of iron phthalocyanine (FePc) complex axially ligated to a preformed 4-mercaptopyridine SAMs. The anodic oxidation of hydrazine in neutral pH conditions with FePc-linked-mercaptopyridine-SAM-modified gold electrode occurred at low overpotential (0.35 V versus Ag|AgCl) and the treatment of the voltammetric data showed that it was a pure diffusion-controlled reaction with the involvement of one electron in the rate-determining step. The mechanism for the interaction of hydrazine with the FePc-SAM is proposed to involve the Fe(III)Pc/Fe(II)Pc redox process. Using cyclic voltammetry (CV) and Osteryoung square wave voltammetry (OSWV), hydrazine was detected over a linear concentration range of 1.3 × 10−5 to 9.2 × 10−5 mol/L with low limits of detection (ca. 5 and 11 μM for OSWV and CV, respectively). At concentrations higher than 1.2 × 10−4 mol/L the anodic peak potential shifted to 0.40 V (versus Ag|AgCl), and this was interpreted to be due to kinetic limitations resulting from the saturation of hydrazine and its oxidation products onto the redox-active monolayer film. This type of metallophthalocyanine-SAM-based electrode is a highly promising electrochemical sensor given its ease of fabrication, good catalytic activity, stability, sensitivity and simplicity.
- Full Text:
- Date Issued: 2005
Electropolymerized Pyrrole-Substituted Manganese Phthalocyanine Films for the Electroassisted Biomimetic Catalytic Reduction of Molecular Oxygen
- Rodrigues, Nazaré Pereira, Obirai, Joe, Nyokong, Tebello, Bedioui, Fethi
- Authors: Rodrigues, Nazaré Pereira , Obirai, Joe , Nyokong, Tebello , Bedioui, Fethi
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289372 , vital:56626 , xlink:href="https://doi.org/10.1002/elan.200403064"
- Description: We report for the first time on the electroassisted biomimetic activation of molecular oxygen by a newly prepared electropolymerized polypyrrole-manganese phthalocyanine film. The prepared films and their intervention in the electroassisted catalytic reduction of molecular oxygen were analyzed by cyclic voltammetry and UV-visible spectrophotometry on optically transparent electrodes. The obtained results demonstrate the probable existence of the key-steps responsible for the suggested formation of the highly reactive manganese oxo intermediate.
- Full Text:
- Date Issued: 2005
- Authors: Rodrigues, Nazaré Pereira , Obirai, Joe , Nyokong, Tebello , Bedioui, Fethi
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289372 , vital:56626 , xlink:href="https://doi.org/10.1002/elan.200403064"
- Description: We report for the first time on the electroassisted biomimetic activation of molecular oxygen by a newly prepared electropolymerized polypyrrole-manganese phthalocyanine film. The prepared films and their intervention in the electroassisted catalytic reduction of molecular oxygen were analyzed by cyclic voltammetry and UV-visible spectrophotometry on optically transparent electrodes. The obtained results demonstrate the probable existence of the key-steps responsible for the suggested formation of the highly reactive manganese oxo intermediate.
- Full Text:
- Date Issued: 2005
Enabling reflexivity and the development of reflexive competence within course processes: a case study of an environmental education professional development course
- Authors: Raven, Glenda C
- Date: 2005
- Subjects: Rhodes University / Gold Fields Course in Environmental Education Environmental education -- Research -- South Africa Environmental education -- South Africa -- Curricula Competency-based education -- South Africa Education and state -- South Africa Education -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1507 , http://hdl.handle.net/10962/d1003389
- Description: This research was undertaken in the context of socio-economic transformation in South Africa, and more specifically, in the context of change in education policy. To support socio-economic transformation in South Africa after the first democratic elections in 1994, a competence-based National Qualifications Framework (NQF) was introduced in 1995. In responding to the particular socio-historical context of South Africa, the South African NQF is underpinned by the notion of applied competence, integrating practical, foundational and reflexive competence, which is the key and distinguishing feature of this competence-based framework. In this context of transformation, the research was aimed at an in-depth exploration of the notion of reflexivity and reflexive competence, and course processes that enable its development, with a view to providing curriculum development insights for learning programme development in the competence-based NQF, more broadly, and environmental education professional development programmes, more specifically. To enable these aims, the research was undertaken in the context of the Rhodes University / Gold Fields Participatory Course in Environmental Education (RU/GF course), as a case example of a professional development course that aims to develop critically reflexive practitioners. Within an interpretivist orientation, a multiple-embedded case study approach was used to gain insight into the relationship between course processes, reflexivity and the development of reflexive competence to clarify and provide a critical perspective on how competence develops in the context of the course. Data was collected over a period of one year using observation, interviewing and document analysis as the primary data collection techniques. Data was analysed through various phases and layers to inform data generation and the synthesising of data for further interpretation. Through the literature review undertaken within the study, various significant insights emerged around the notion of reflexivity and reflexive competence. Firstly, there appears to be a need to distinguish between reflexivity as social processes of change (social actions and interactions within social systems, structures and processes) and reflexive competence (a range of integrative elements of competence) that provides the evidence of an engagement within social processes of change. The second key insight emerging is the significance of social structure in shaping participation in reflexive processes, thus emphasising the duality of structure as both the medium for, and outcome of reflexive social actions and interactions and so challenges the deterministic conception of social structure. Further, the significance of an epistemologically framed notion of reflexivity and reflexive competence emerged, in the context of responding to the complex and uncertain quality of socio-ecological risks and in supporting change in context. Reflexivity, distinguished from processes of critical reflection, foregrounds a critical exploration of both knowledge and unawareness. As such a reinterpretation of reflexive competence is offered as a process of potential challenge to dominant and reigning forms of reasoning (knowledge frameworks) and consequent principles of ordering. Through this reframing of reflexive competence, the potential exists to destabilise dominant forms of reasoning and principles of ordering to create a broader scope of possibilities for action and change in context. This reframing of reflexive competence in the context of transformation in South Africa has critical implications for engaging within processes of learning programme design in the NQF to support an engagement within reflexive processes of change and the development of a range of integrative elements of reflexive competence. In this light, the study attempts to make the following contribution to curriculum deliberations within the context of environmental education and the NQF in relation to reflexivity, reflexive competence and change: ♦ Reflexivity is conceptualised as social processes of change with reflexive competence providing evidence of engagement within these social processes of change; ♦ An epistemologically framed conception of reflexivity and reflexive competence recognises how rules of reason and the ordering of the ‘reasonable’ person come to shape social life; and so ♦ Change is conceptualised as ruptures and breaks in dominant knowledge frames and the power relations embedded in these; ♦ Unawareness emerges as a key dimension within reflexive environmental education processes in responding to the unpredictable and uncertain nature of risks; ♦ An epistemological framing of reflexivity and reflexive competence highlights the need to develop open processes of learning to support the critical exploration of knowledge and unawareness; and ♦ Within this framing of reflexivity and reflexive competence, the difficulty emerges in specifically predefining reflexive competence to inform standard setting processes within a context of intended change. In framing data within this emerging conception of reflexivity and reflexive competence, a review of course processes highlighted potential areas for reorienting the RU/GF course to support change in context, for which I make specific recommendations. Drawing on the review of course processes in the RU/GF course, and in light of the reframing of reflexivity and reflexive competence, I further offer summative discussions as ‘possible implications’ for learning programme design in the South African competence-based NQF, broadly and environmental education professional development programmes in this framework, more specifically.
- Full Text:
- Date Issued: 2005
- Authors: Raven, Glenda C
- Date: 2005
- Subjects: Rhodes University / Gold Fields Course in Environmental Education Environmental education -- Research -- South Africa Environmental education -- South Africa -- Curricula Competency-based education -- South Africa Education and state -- South Africa Education -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1507 , http://hdl.handle.net/10962/d1003389
- Description: This research was undertaken in the context of socio-economic transformation in South Africa, and more specifically, in the context of change in education policy. To support socio-economic transformation in South Africa after the first democratic elections in 1994, a competence-based National Qualifications Framework (NQF) was introduced in 1995. In responding to the particular socio-historical context of South Africa, the South African NQF is underpinned by the notion of applied competence, integrating practical, foundational and reflexive competence, which is the key and distinguishing feature of this competence-based framework. In this context of transformation, the research was aimed at an in-depth exploration of the notion of reflexivity and reflexive competence, and course processes that enable its development, with a view to providing curriculum development insights for learning programme development in the competence-based NQF, more broadly, and environmental education professional development programmes, more specifically. To enable these aims, the research was undertaken in the context of the Rhodes University / Gold Fields Participatory Course in Environmental Education (RU/GF course), as a case example of a professional development course that aims to develop critically reflexive practitioners. Within an interpretivist orientation, a multiple-embedded case study approach was used to gain insight into the relationship between course processes, reflexivity and the development of reflexive competence to clarify and provide a critical perspective on how competence develops in the context of the course. Data was collected over a period of one year using observation, interviewing and document analysis as the primary data collection techniques. Data was analysed through various phases and layers to inform data generation and the synthesising of data for further interpretation. Through the literature review undertaken within the study, various significant insights emerged around the notion of reflexivity and reflexive competence. Firstly, there appears to be a need to distinguish between reflexivity as social processes of change (social actions and interactions within social systems, structures and processes) and reflexive competence (a range of integrative elements of competence) that provides the evidence of an engagement within social processes of change. The second key insight emerging is the significance of social structure in shaping participation in reflexive processes, thus emphasising the duality of structure as both the medium for, and outcome of reflexive social actions and interactions and so challenges the deterministic conception of social structure. Further, the significance of an epistemologically framed notion of reflexivity and reflexive competence emerged, in the context of responding to the complex and uncertain quality of socio-ecological risks and in supporting change in context. Reflexivity, distinguished from processes of critical reflection, foregrounds a critical exploration of both knowledge and unawareness. As such a reinterpretation of reflexive competence is offered as a process of potential challenge to dominant and reigning forms of reasoning (knowledge frameworks) and consequent principles of ordering. Through this reframing of reflexive competence, the potential exists to destabilise dominant forms of reasoning and principles of ordering to create a broader scope of possibilities for action and change in context. This reframing of reflexive competence in the context of transformation in South Africa has critical implications for engaging within processes of learning programme design in the NQF to support an engagement within reflexive processes of change and the development of a range of integrative elements of reflexive competence. In this light, the study attempts to make the following contribution to curriculum deliberations within the context of environmental education and the NQF in relation to reflexivity, reflexive competence and change: ♦ Reflexivity is conceptualised as social processes of change with reflexive competence providing evidence of engagement within these social processes of change; ♦ An epistemologically framed conception of reflexivity and reflexive competence recognises how rules of reason and the ordering of the ‘reasonable’ person come to shape social life; and so ♦ Change is conceptualised as ruptures and breaks in dominant knowledge frames and the power relations embedded in these; ♦ Unawareness emerges as a key dimension within reflexive environmental education processes in responding to the unpredictable and uncertain nature of risks; ♦ An epistemological framing of reflexivity and reflexive competence highlights the need to develop open processes of learning to support the critical exploration of knowledge and unawareness; and ♦ Within this framing of reflexivity and reflexive competence, the difficulty emerges in specifically predefining reflexive competence to inform standard setting processes within a context of intended change. In framing data within this emerging conception of reflexivity and reflexive competence, a review of course processes highlighted potential areas for reorienting the RU/GF course to support change in context, for which I make specific recommendations. Drawing on the review of course processes in the RU/GF course, and in light of the reframing of reflexivity and reflexive competence, I further offer summative discussions as ‘possible implications’ for learning programme design in the South African competence-based NQF, broadly and environmental education professional development programmes in this framework, more specifically.
- Full Text:
- Date Issued: 2005
Enzymatic recovery of rhodium(III) from aqueous solution and industrial effluent using sulphate reducing bacteria: role of a hydrogenase enzyme
- Authors: Ngwenya, Nonhlanhla
- Date: 2005
- Subjects: Enzymes , Rhodium , Enzymes -- Industrial applications , Sulfur bacteria , Hydrogenation , Hydragenase , Factory and trade waste -- Purification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3956 , http://hdl.handle.net/10962/d1004015 , Enzymes , Rhodium , Enzymes -- Industrial applications , Sulfur bacteria , Hydrogenation , Hydragenase , Factory and trade waste -- Purification
- Description: In an attempt to overcome the high maintenance and costs associated with traditional physico-chemical methods, much work is being done on the application of enzymes for the recovery of valuable metals from solutions and industrial effluents. One of the most widely studied enzymatic metal recovery systems uses hydrogenase enzymes, particularly from sulphate reducing bacteria (SRB). While it is known that hydrogenases from SRB mediate the reductive precipitation of metals, the mechanism of enzymatic reduction, however, is not yet fully understood. The main aim of the present study was to investigate the role of a hydrogenase enzyme in the removal of rhodium from both aqueous solution and industrial effluent. A quantitative analysis of the rate of removal of rhodium(III) by a resting SRB consortium under different initial rhodium and biomass concentrations, pH, temperature, presence and absence of SRB cells and electron donor, was studied. Rhodium speciation was found to be the main factor controlling the rate of removal of rhodium from solution. SRB cells were found to have a higher affinity for anionic rhodium species, as compared to both cationic and neutral species, which become abundant when speciation equilibrium was reached. Consequently, a pH-dependant rate of rhodium removal from solution was observed. The maximum SRB uptake capacity for rhodium was found to be 66 mg rhodium per g of resting SRB biomass. Electron microscopy studies revealed a time-dependant localization and distribution of rhodium precipitates, initially intracellularly and then extracellularly, suggesting the involvement of an enzymatic reductive precipitation process. A hydrogenase enzyme capable of reducing rhodium(III) from solution was isolated and purified by PEG, DEAE-Sephacel anion exchanger and Sephadex G200 gel exclusion. A distinct protein band with a molecular weight of 62kDa was obtained when the hydrogenase containing fractions were subjected to a 10% SDS-PAGE. Characterization studies indicated that the purified hydrogenase had an optimum pH and temperature of 8 and 40°C, respectively. A maximum of 88% of the initial rhodium in solution was removed when the purified hydrogenase was incubated under hydrogen. Due to the low pH of the industrial effluent (1.31), the enzymatic reduction of rhodium by the purified hydrogenase was greatly retarded. It was apparent that industrial effluent pretreatment was necessary before the application an enzymatic treatment method. In the present study, however, it has been established that SRB are good candidates for the enzymatic recovery of rhodium from both solution and effluent.
- Full Text:
- Date Issued: 2005
- Authors: Ngwenya, Nonhlanhla
- Date: 2005
- Subjects: Enzymes , Rhodium , Enzymes -- Industrial applications , Sulfur bacteria , Hydrogenation , Hydragenase , Factory and trade waste -- Purification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3956 , http://hdl.handle.net/10962/d1004015 , Enzymes , Rhodium , Enzymes -- Industrial applications , Sulfur bacteria , Hydrogenation , Hydragenase , Factory and trade waste -- Purification
- Description: In an attempt to overcome the high maintenance and costs associated with traditional physico-chemical methods, much work is being done on the application of enzymes for the recovery of valuable metals from solutions and industrial effluents. One of the most widely studied enzymatic metal recovery systems uses hydrogenase enzymes, particularly from sulphate reducing bacteria (SRB). While it is known that hydrogenases from SRB mediate the reductive precipitation of metals, the mechanism of enzymatic reduction, however, is not yet fully understood. The main aim of the present study was to investigate the role of a hydrogenase enzyme in the removal of rhodium from both aqueous solution and industrial effluent. A quantitative analysis of the rate of removal of rhodium(III) by a resting SRB consortium under different initial rhodium and biomass concentrations, pH, temperature, presence and absence of SRB cells and electron donor, was studied. Rhodium speciation was found to be the main factor controlling the rate of removal of rhodium from solution. SRB cells were found to have a higher affinity for anionic rhodium species, as compared to both cationic and neutral species, which become abundant when speciation equilibrium was reached. Consequently, a pH-dependant rate of rhodium removal from solution was observed. The maximum SRB uptake capacity for rhodium was found to be 66 mg rhodium per g of resting SRB biomass. Electron microscopy studies revealed a time-dependant localization and distribution of rhodium precipitates, initially intracellularly and then extracellularly, suggesting the involvement of an enzymatic reductive precipitation process. A hydrogenase enzyme capable of reducing rhodium(III) from solution was isolated and purified by PEG, DEAE-Sephacel anion exchanger and Sephadex G200 gel exclusion. A distinct protein band with a molecular weight of 62kDa was obtained when the hydrogenase containing fractions were subjected to a 10% SDS-PAGE. Characterization studies indicated that the purified hydrogenase had an optimum pH and temperature of 8 and 40°C, respectively. A maximum of 88% of the initial rhodium in solution was removed when the purified hydrogenase was incubated under hydrogen. Due to the low pH of the industrial effluent (1.31), the enzymatic reduction of rhodium by the purified hydrogenase was greatly retarded. It was apparent that industrial effluent pretreatment was necessary before the application an enzymatic treatment method. In the present study, however, it has been established that SRB are good candidates for the enzymatic recovery of rhodium from both solution and effluent.
- Full Text:
- Date Issued: 2005