Challenges facing probation officers working with young persons in conflict with the law
- Authors: Volsak, Nobubele
- Date: 2001
- Subjects: Probation officers Probation officers -- Attitudes -- South Africa -- Eastern Cape Juvenile delinquents Probation
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:710 , http://hdl.handle.net/10962/d1006534
- Description: This study aimed at focusing on the challenges facing probation officers working with young persons in conflict with the law, in the Eastern region, which forms part of the Eastern Cape Province. The main purpose of the study was to explore the experiences of probation officers in terms of the legislation that they are using when making decisions pertaining to young persons and the types of programmes that they offer to young persons for diversion and prevention purposes. The researcher also wanted to generate a greater understanding of the resources which probation officers have and need in order to run their programmes successfully to young persons, as well as to explore their feelings about working with young persons. The researcher did some literature review in relation to this field, where it became evident that probation services in respect of young persons in conflict with the law, is a relatively new field of specialisation in South Africa. This field started around 1995 as a result of the Inter - Ministerial Committee (IMC) on young people at risk, which was set up to respond and manage the crisis of more than one thousand children who were released from prisons and police cells. The IMC then, identified probation officers as leading role players in dealing with young persons in conflict with the law. An exploratory (non - experimental) design was used to carry out the research. A qualitative research method was also used as it attempts to describe and explain social reality from the points of view of the participants. This is because the researcher was interested to find out the experiences of probation officers in relation to their work with young persons. A non - probability purposive sample of all (11) probation officers was used. A semi - structured interview schedule with both closed and open - ended questions was used to collect data. All the information gathered from those personal interviews, was analysed by hand because the researcher wanted to interpret and produce social explanations. The findings of this small - scale study have revealed that there are a number of challenges facing probation officers. For example presently there is no comprehensive legislation for the management of young persons caught up in the criminal justice system. Instead, limited provisions are spread throughout a number of separate statutes, which make it difficult for probation officers to apply them. This study has also revealed that there is a shortage of human and material resources, which somehow impact negatively on how probation officers render services to their clientele. All probation officers in this study have positive feelings and attitudes about their work despite the fact that there are some challenges facing them that need to be addressed. Specific recommendations have been made based on the findings of this study, which could contribute to the development of probation services in respect of young persons in conf lict with the law
- Full Text:
- Date Issued: 2001
- Authors: Volsak, Nobubele
- Date: 2001
- Subjects: Probation officers Probation officers -- Attitudes -- South Africa -- Eastern Cape Juvenile delinquents Probation
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:710 , http://hdl.handle.net/10962/d1006534
- Description: This study aimed at focusing on the challenges facing probation officers working with young persons in conflict with the law, in the Eastern region, which forms part of the Eastern Cape Province. The main purpose of the study was to explore the experiences of probation officers in terms of the legislation that they are using when making decisions pertaining to young persons and the types of programmes that they offer to young persons for diversion and prevention purposes. The researcher also wanted to generate a greater understanding of the resources which probation officers have and need in order to run their programmes successfully to young persons, as well as to explore their feelings about working with young persons. The researcher did some literature review in relation to this field, where it became evident that probation services in respect of young persons in conflict with the law, is a relatively new field of specialisation in South Africa. This field started around 1995 as a result of the Inter - Ministerial Committee (IMC) on young people at risk, which was set up to respond and manage the crisis of more than one thousand children who were released from prisons and police cells. The IMC then, identified probation officers as leading role players in dealing with young persons in conflict with the law. An exploratory (non - experimental) design was used to carry out the research. A qualitative research method was also used as it attempts to describe and explain social reality from the points of view of the participants. This is because the researcher was interested to find out the experiences of probation officers in relation to their work with young persons. A non - probability purposive sample of all (11) probation officers was used. A semi - structured interview schedule with both closed and open - ended questions was used to collect data. All the information gathered from those personal interviews, was analysed by hand because the researcher wanted to interpret and produce social explanations. The findings of this small - scale study have revealed that there are a number of challenges facing probation officers. For example presently there is no comprehensive legislation for the management of young persons caught up in the criminal justice system. Instead, limited provisions are spread throughout a number of separate statutes, which make it difficult for probation officers to apply them. This study has also revealed that there is a shortage of human and material resources, which somehow impact negatively on how probation officers render services to their clientele. All probation officers in this study have positive feelings and attitudes about their work despite the fact that there are some challenges facing them that need to be addressed. Specific recommendations have been made based on the findings of this study, which could contribute to the development of probation services in respect of young persons in conf lict with the law
- Full Text:
- Date Issued: 2001
Change management implications of a retrenchment strategy in a selected section of a telecommunications organisation
- Authors: Aucamp, Mertz
- Date: 2001
- Subjects: Organizational change -- Management , Downsizing of organizations -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10847 , http://hdl.handle.net/10948/46 , Organizational change -- Management , Downsizing of organizations -- South Africa
- Description: An audit report by the Australian National Audit Office (ANAO) indicated that a company needs to ensure that support is provided to those employees who remain after a staff reduction process and that their needs are managed effectively. One of the recommendations by ANAO for companies that are embarking on restructuring and future staff reduction programs, is the facilitation of change management workshops, or intervention to prepare the staff to manage change. A literature study revealed that no change management model existed that specifically focused on the “survivors” of a retrenchment or restructuring strategy in a company. The literature study was therefore used to assist in developing a change management in Telkom SA. Pre-assessment and post-assessment questionnaires were developed to test the employees’ abilities to manage change and their understanding of the changes that the telecommunications industry is facing. The findings of the survey showed a high level of employee tolerance to change and illuminated the value that was added by the developed change management model.
- Full Text:
- Date Issued: 2001
- Authors: Aucamp, Mertz
- Date: 2001
- Subjects: Organizational change -- Management , Downsizing of organizations -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10847 , http://hdl.handle.net/10948/46 , Organizational change -- Management , Downsizing of organizations -- South Africa
- Description: An audit report by the Australian National Audit Office (ANAO) indicated that a company needs to ensure that support is provided to those employees who remain after a staff reduction process and that their needs are managed effectively. One of the recommendations by ANAO for companies that are embarking on restructuring and future staff reduction programs, is the facilitation of change management workshops, or intervention to prepare the staff to manage change. A literature study revealed that no change management model existed that specifically focused on the “survivors” of a retrenchment or restructuring strategy in a company. The literature study was therefore used to assist in developing a change management in Telkom SA. Pre-assessment and post-assessment questionnaires were developed to test the employees’ abilities to manage change and their understanding of the changes that the telecommunications industry is facing. The findings of the survey showed a high level of employee tolerance to change and illuminated the value that was added by the developed change management model.
- Full Text:
- Date Issued: 2001
Changes in the abundance of cells in the anterior pituitary gland and the possible roles of luteinizing hormone, prolactin and progesterone in the control of delayed implantation in the straw-coloured fruit bat (Eidolon helvum)
- Simbauni, J A, Bernard, Ric T F
- Authors: Simbauni, J A , Bernard, Ric T F
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447131 , vital:74586 , https://doi.org/10.1080/15627020.2001.11657115
- Description: Eidolon helvum (Megachiroptera) is a large frugivorous bat found in equatorial and tropical Africa. The reproductive cycle is characterized by a three-month period of delayed implantation and the total length of pregnancy may be as much as 10 months. A histochemical study of the gonadotrophs and mammotrophs of the anterior pituitary, in conjunction with assays of LH-like, progesterone-like and prolactin-like immunoreactivity in the plasma suggest that during delayed implantation the gonadotrophs were inactive while the mammotrophs were active and plasma PRL-like immunoreactivity high. We interpret this as indicating that, in the straw-coloured fruit bat, implantation was inhibited by high levels of prolactin and, as such, the endocrine control of delayed implantation may be quite different from that described for other mammals.
- Full Text:
- Date Issued: 2001
- Authors: Simbauni, J A , Bernard, Ric T F
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447131 , vital:74586 , https://doi.org/10.1080/15627020.2001.11657115
- Description: Eidolon helvum (Megachiroptera) is a large frugivorous bat found in equatorial and tropical Africa. The reproductive cycle is characterized by a three-month period of delayed implantation and the total length of pregnancy may be as much as 10 months. A histochemical study of the gonadotrophs and mammotrophs of the anterior pituitary, in conjunction with assays of LH-like, progesterone-like and prolactin-like immunoreactivity in the plasma suggest that during delayed implantation the gonadotrophs were inactive while the mammotrophs were active and plasma PRL-like immunoreactivity high. We interpret this as indicating that, in the straw-coloured fruit bat, implantation was inhibited by high levels of prolactin and, as such, the endocrine control of delayed implantation may be quite different from that described for other mammals.
- Full Text:
- Date Issued: 2001
Chemical studies of chromone derivatives
- Authors: Sabbagh, Liezel Veronica
- Date: 2001
- Subjects: Benzopyrans Heterocyclic compounds -- Derivatives Coumarins
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4424 , http://hdl.handle.net/10962/d1006899
- Description:
This study has focussed on several aspects of chromone chemistry, viz., (i) the influence of remote substituents on the basicity of 2-(N,N-dimethylamino)chromones, (ii) MoritaBaylis-Hillman reactions of substituted chromone-3-carbaldehydes and (iii) an investigation into the application of chromone chemistry in the total synthesis of the marine natural product, Rietone A. Selected 2-(N,N-dimethylamino )chromones were prepared using two different methods; firstly, via cyclisation of salicylate-derived N,N-dimethyl-3;.(2-hydroxyphenyl)-3- oxopropanamide precursors and, secondly, via 2-hydroxyacetophenone boron difluoride complexes. ¹³C NMR analysis of the 6- and 7-methoxy-2-(N,N-dimethylamino)chromones confirmed that protonation occurs at the chromone carbonyl oxygen rather than the amino nitrogen - a conclusion supported by mol~cular orbital calculations. Potentiometric analysis of 2-(N,N-dimethylamino )chromones in ethanol-water afforded pKa (pK [subscript a]) values in the range 2.22 - 2.52. The observed trend has been rationalised in terms of substituent effects with the aid of molecular orbital calculations at the semi-empirical and ab initio levels, while hydrogen-bonding effects have been used to account for the apparently anomalous result obtained for the 6-nitro derivative. A series of seven substituted chromone-3-carbaldehydes, prepared by the application of Vilsmeier-Haack methodology to the corresponding 2-hydroxyacetophenones, have been examined as substrates for Morita-Baylis-Hillman reactions, using DABCO as the catalyst and three different activated alkenes, viz., methyl acrylate, methyl vinyl ketone and acrylonitrile. In all cases, with the exception of 6-nitrochromone-3-carbaldehyde, the reactions have been shown to afford the expected Morita-Baylis-Hillman products. Use of methyl acrylate and methyl vinyl ketone as the activated alkene has been observed to afford additional, unprecedented dimeric products, which have been unambiguously characterised using a combination of single crystal X-ray analysis and spectroscopic (high resolution MS and NMR) techniques. Different dimer-like adducts have been isolated from reactions in which acrylonitrile was used as the activated alkene, and the structures of these novel products have-been determined
- Full Text:
- Date Issued: 2001
- Authors: Sabbagh, Liezel Veronica
- Date: 2001
- Subjects: Benzopyrans Heterocyclic compounds -- Derivatives Coumarins
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4424 , http://hdl.handle.net/10962/d1006899
- Description:
This study has focussed on several aspects of chromone chemistry, viz., (i) the influence of remote substituents on the basicity of 2-(N,N-dimethylamino)chromones, (ii) MoritaBaylis-Hillman reactions of substituted chromone-3-carbaldehydes and (iii) an investigation into the application of chromone chemistry in the total synthesis of the marine natural product, Rietone A. Selected 2-(N,N-dimethylamino )chromones were prepared using two different methods; firstly, via cyclisation of salicylate-derived N,N-dimethyl-3;.(2-hydroxyphenyl)-3- oxopropanamide precursors and, secondly, via 2-hydroxyacetophenone boron difluoride complexes. ¹³C NMR analysis of the 6- and 7-methoxy-2-(N,N-dimethylamino)chromones confirmed that protonation occurs at the chromone carbonyl oxygen rather than the amino nitrogen - a conclusion supported by mol~cular orbital calculations. Potentiometric analysis of 2-(N,N-dimethylamino )chromones in ethanol-water afforded pKa (pK [subscript a]) values in the range 2.22 - 2.52. The observed trend has been rationalised in terms of substituent effects with the aid of molecular orbital calculations at the semi-empirical and ab initio levels, while hydrogen-bonding effects have been used to account for the apparently anomalous result obtained for the 6-nitro derivative. A series of seven substituted chromone-3-carbaldehydes, prepared by the application of Vilsmeier-Haack methodology to the corresponding 2-hydroxyacetophenones, have been examined as substrates for Morita-Baylis-Hillman reactions, using DABCO as the catalyst and three different activated alkenes, viz., methyl acrylate, methyl vinyl ketone and acrylonitrile. In all cases, with the exception of 6-nitrochromone-3-carbaldehyde, the reactions have been shown to afford the expected Morita-Baylis-Hillman products. Use of methyl acrylate and methyl vinyl ketone as the activated alkene has been observed to afford additional, unprecedented dimeric products, which have been unambiguously characterised using a combination of single crystal X-ray analysis and spectroscopic (high resolution MS and NMR) techniques. Different dimer-like adducts have been isolated from reactions in which acrylonitrile was used as the activated alkene, and the structures of these novel products have-been determined
- Full Text:
- Date Issued: 2001
Clustering as a strategy for manufacturing performance in the Eastern Cape Automotive industry
- Makuwaza, Gwynneth Chandakaita
- Authors: Makuwaza, Gwynneth Chandakaita
- Date: 2001
- Subjects: Automobile industry and trade , Automobile industry and trade -- South Africa -- Eastern Cape , Automobile industry and trade -- South Africa -- Eastern Cape -- Performance
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:937 , http://hdl.handle.net/10962/d1002670 , Automobile industry and trade , Automobile industry and trade -- South Africa -- Eastern Cape , Automobile industry and trade -- South Africa -- Eastern Cape -- Performance
- Description: South Africa's current industrial policy focuses on the economy at two levels: a sectoral and spatial level. The former relates to the manner in which industrial policy is concentrating on particular sectors i.e. industrial clusters. This shift in industrial policy from targeting individual industries to an emphasis on industrial clusters, has complemented the change in focus to export promotion under trade policy. Furthermore, there has been increasing recognition of the need to improve industry performance and competitiveness in order to successfully implement export growth. Industry clusters are considered as having the potential to increase manufacturing performance and can provide the basis for sustainable competitive advantage for nations. Consequently the concept of industry clusters was introduced in South Africa in 1997. Because industry clusters are relatively new in South Africa, most of the cluster initiatives in various sectors of the economy are in their early stages of development. Nevertheless, some are already showing signs of potential success in increasing competitiveness in particular sectors. This thesis uses Porter's "diamond" framework apprdach to investigate whether clustering has improved the manufacturing performance of the motor industry in the Eastern Cape. International experience from both developed and developing countries will illustrate the potential of clustering as a powerful strategy in increasing manufacturing performance and consequently competitiveness. Ultimately this should lead to long-term economic development, especially if government adopts clusterbased economic development policies. Information from a survey conducted on both the motor vehicle assemblers and component suppliers is used in this study. The findings reveal that it is mainly the motor vehicle assemblers who have experienced some improvements in manufacturing performance. The components sector on the other hand has not experienced any such improvements. This thesis concludes with the recommendation that it is important to develop cluster policy as a broader and dynamic view of competition. The main emphasis under such policy would be a move from targeting particular industries and providing subsidies towards focusing attention to all clusters in the economy. To effectively apply such a policy requires the repositioning of national, local and provincial government in order to become more involved in regional development issues. Moreover, the various levels of government need to incorporate cluster policy into their competitive strategies.
- Full Text:
- Date Issued: 2001
- Authors: Makuwaza, Gwynneth Chandakaita
- Date: 2001
- Subjects: Automobile industry and trade , Automobile industry and trade -- South Africa -- Eastern Cape , Automobile industry and trade -- South Africa -- Eastern Cape -- Performance
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:937 , http://hdl.handle.net/10962/d1002670 , Automobile industry and trade , Automobile industry and trade -- South Africa -- Eastern Cape , Automobile industry and trade -- South Africa -- Eastern Cape -- Performance
- Description: South Africa's current industrial policy focuses on the economy at two levels: a sectoral and spatial level. The former relates to the manner in which industrial policy is concentrating on particular sectors i.e. industrial clusters. This shift in industrial policy from targeting individual industries to an emphasis on industrial clusters, has complemented the change in focus to export promotion under trade policy. Furthermore, there has been increasing recognition of the need to improve industry performance and competitiveness in order to successfully implement export growth. Industry clusters are considered as having the potential to increase manufacturing performance and can provide the basis for sustainable competitive advantage for nations. Consequently the concept of industry clusters was introduced in South Africa in 1997. Because industry clusters are relatively new in South Africa, most of the cluster initiatives in various sectors of the economy are in their early stages of development. Nevertheless, some are already showing signs of potential success in increasing competitiveness in particular sectors. This thesis uses Porter's "diamond" framework apprdach to investigate whether clustering has improved the manufacturing performance of the motor industry in the Eastern Cape. International experience from both developed and developing countries will illustrate the potential of clustering as a powerful strategy in increasing manufacturing performance and consequently competitiveness. Ultimately this should lead to long-term economic development, especially if government adopts clusterbased economic development policies. Information from a survey conducted on both the motor vehicle assemblers and component suppliers is used in this study. The findings reveal that it is mainly the motor vehicle assemblers who have experienced some improvements in manufacturing performance. The components sector on the other hand has not experienced any such improvements. This thesis concludes with the recommendation that it is important to develop cluster policy as a broader and dynamic view of competition. The main emphasis under such policy would be a move from targeting particular industries and providing subsidies towards focusing attention to all clusters in the economy. To effectively apply such a policy requires the repositioning of national, local and provincial government in order to become more involved in regional development issues. Moreover, the various levels of government need to incorporate cluster policy into their competitive strategies.
- Full Text:
- Date Issued: 2001
Cognitive behavioural treatment of chronic fatigue syndrome: an in-depth case study
- Authors: Rusch, Mary L
- Date: 2001
- Subjects: Chronic fatigue syndrome , Chronic fatigue syndrome -- Psychological aspects , Chronic fatigue syndrome -- Exercise therapy , Chronic fatigue syndrome -- Treatment
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3046 , http://hdl.handle.net/10962/d1002555
- Description: Chronic Fatigue Syndrome (CFS) is a chronic disabling condition characterised by persistent physical and mental fatigue, and a variety of somatic, psychological and neurological symptoms. The aetiology of CFS is unknown and the cause of the illness remains controversial. Cognitive-behavioural therapy (CBT) is a non-pharmacological treatment approach that has been shown to be effective in treating patients with CFS. It is based on a model that hypothesises that certain maladaptive thoughts and dysfunctional beliefs may contribute to self-defeating behaviour that perpetuates symptoms and disability, and thereby impedes recovery. The main aim of this study was to critically examine the cognitive-behavioural approach of CFS outlined by Sharpe, Chalder, Palmer & Wessely (1997) by conducting three in-depth case studies. An additional aim was to present a full cognitive developmental case conceptualisation of CFS based on the theories of Leahy (1996) and Young (1994). This case study evaluated the effectiveness of a CBT treatment programme in a 48-year-old Caucasian woman diagnosed with CFS for three years. The treatment consisted of sixteen sessions of CBT and was evaluated both quantitatively and qualitatively. On the basis of this study, a set of core maladaptive schema in the area of disconnection and rejection was identified. In addition, it was found that specific compensatory schemas had developed to offset the core maladaptive schemas and that this compensatory strategy played an important role in maintaining the condition. The results also showed a significant decline in fatigue coupled with a moderate decline in functional disability and depression. A one-month follow-up interview revealed evidence of a substantial consolidation of therapeutic gains in that the improvements observed at the end of the treatment were sustained. Finally, the feasibility of incorporating a cognitive-developmental and/or schema-focused model into the standard CBT treatment model is discussed and the case study method as a research toll is evaluated in light of the findings.
- Full Text:
- Date Issued: 2001
- Authors: Rusch, Mary L
- Date: 2001
- Subjects: Chronic fatigue syndrome , Chronic fatigue syndrome -- Psychological aspects , Chronic fatigue syndrome -- Exercise therapy , Chronic fatigue syndrome -- Treatment
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3046 , http://hdl.handle.net/10962/d1002555
- Description: Chronic Fatigue Syndrome (CFS) is a chronic disabling condition characterised by persistent physical and mental fatigue, and a variety of somatic, psychological and neurological symptoms. The aetiology of CFS is unknown and the cause of the illness remains controversial. Cognitive-behavioural therapy (CBT) is a non-pharmacological treatment approach that has been shown to be effective in treating patients with CFS. It is based on a model that hypothesises that certain maladaptive thoughts and dysfunctional beliefs may contribute to self-defeating behaviour that perpetuates symptoms and disability, and thereby impedes recovery. The main aim of this study was to critically examine the cognitive-behavioural approach of CFS outlined by Sharpe, Chalder, Palmer & Wessely (1997) by conducting three in-depth case studies. An additional aim was to present a full cognitive developmental case conceptualisation of CFS based on the theories of Leahy (1996) and Young (1994). This case study evaluated the effectiveness of a CBT treatment programme in a 48-year-old Caucasian woman diagnosed with CFS for three years. The treatment consisted of sixteen sessions of CBT and was evaluated both quantitatively and qualitatively. On the basis of this study, a set of core maladaptive schema in the area of disconnection and rejection was identified. In addition, it was found that specific compensatory schemas had developed to offset the core maladaptive schemas and that this compensatory strategy played an important role in maintaining the condition. The results also showed a significant decline in fatigue coupled with a moderate decline in functional disability and depression. A one-month follow-up interview revealed evidence of a substantial consolidation of therapeutic gains in that the improvements observed at the end of the treatment were sustained. Finally, the feasibility of incorporating a cognitive-developmental and/or schema-focused model into the standard CBT treatment model is discussed and the case study method as a research toll is evaluated in light of the findings.
- Full Text:
- Date Issued: 2001
Community knowledge, cohesion and environmental sustainability : an educational case study in Clarkson
- Authors: Uithaler, Eldrid Marlon
- Date: 2001
- Subjects: Community life -- South Africa Social participation -- South Africa Community development -- South Africa Competency-based education -- South Africa Competency-based education -- Curricula
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1453 , http://hdl.handle.net/10962/d1003334
- Description: An ethnographic case study was done in the rural community of Clarkson which lies at the foot of the Tsitsikamma Mountains in the Eastern Cape, South Africa. Rural communities gathered and developed local wisdom on the natural resources around them. The study shows that in the past, life in Clarkson was characterised by such shared wisdom, an abundance of natural resources, as well as strong community cohesion. With the advent of modern lifestyles community cohesion and practices were disrupted and today, people living in Clarkson are less dependent on each other and on local resources. This study suggests that some of the past wisdom, community knowledge, practices and skills that existed for ages in Clarkson, can still be useful today in the context of environmental sustainability. The incorporation of this knowledge into the new outcomes-based education curriculum in South Africa and the local school curriculum, is explored.
- Full Text:
- Date Issued: 2001
- Authors: Uithaler, Eldrid Marlon
- Date: 2001
- Subjects: Community life -- South Africa Social participation -- South Africa Community development -- South Africa Competency-based education -- South Africa Competency-based education -- Curricula
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1453 , http://hdl.handle.net/10962/d1003334
- Description: An ethnographic case study was done in the rural community of Clarkson which lies at the foot of the Tsitsikamma Mountains in the Eastern Cape, South Africa. Rural communities gathered and developed local wisdom on the natural resources around them. The study shows that in the past, life in Clarkson was characterised by such shared wisdom, an abundance of natural resources, as well as strong community cohesion. With the advent of modern lifestyles community cohesion and practices were disrupted and today, people living in Clarkson are less dependent on each other and on local resources. This study suggests that some of the past wisdom, community knowledge, practices and skills that existed for ages in Clarkson, can still be useful today in the context of environmental sustainability. The incorporation of this knowledge into the new outcomes-based education curriculum in South Africa and the local school curriculum, is explored.
- Full Text:
- Date Issued: 2001
Comparative photosensitised transformation of polychlorophenols with different sulphonated metallophthalocyanine complexes in aqueous medium
- Ozoemena, Kenneth, Kuznetsova, Nina, Nyokong, Tebello
- Authors: Ozoemena, Kenneth , Kuznetsova, Nina , Nyokong, Tebello
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/291520 , vital:56883 , xlink:href="https://doi.org/10.1016/S1381-1169(01)00243-6"
- Description: The relative efficiencies for the oxidation of trichlorophenol (TCP) and pentachlorophenol (PCP), sensitised by sulphonated phthalocyanine complexes containing Zn, Al, Sn and Si as central metals, were studied in aqueous solutions. For the first time, sulphonated silicon and tin phthalocyanines were synthesised and their activity towards photosensitisation of singlet oxygen and photo-oxidation of polychlorophenols was examined. The efficiency of the sensitised photo-oxidative degradation of polychlorophenols depends not only on singlet oxygen quantum yield of sensitiser, but also on its stability. The influence of substrate structure and the pH of the solution on the photo-oxidation efficiency, as well as on the sensitiser photodegradation were studied. It was found that the contribution of the Type II (singlet oxygen-mediated) mechanism to the relative efficiency of the photosensitised photo-oxidation of the phenol, decreased from phenol to p-chlorophenol, TCP and PCP, whereas Type I radical pathway increased. The results obtained for PCP give evidence that electron transfer from the excited sensitiser to the substrate in its unionised form is responsible for enhanced sensitiser photodegradation.
- Full Text:
- Date Issued: 2001
- Authors: Ozoemena, Kenneth , Kuznetsova, Nina , Nyokong, Tebello
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/291520 , vital:56883 , xlink:href="https://doi.org/10.1016/S1381-1169(01)00243-6"
- Description: The relative efficiencies for the oxidation of trichlorophenol (TCP) and pentachlorophenol (PCP), sensitised by sulphonated phthalocyanine complexes containing Zn, Al, Sn and Si as central metals, were studied in aqueous solutions. For the first time, sulphonated silicon and tin phthalocyanines were synthesised and their activity towards photosensitisation of singlet oxygen and photo-oxidation of polychlorophenols was examined. The efficiency of the sensitised photo-oxidative degradation of polychlorophenols depends not only on singlet oxygen quantum yield of sensitiser, but also on its stability. The influence of substrate structure and the pH of the solution on the photo-oxidation efficiency, as well as on the sensitiser photodegradation were studied. It was found that the contribution of the Type II (singlet oxygen-mediated) mechanism to the relative efficiency of the photosensitised photo-oxidation of the phenol, decreased from phenol to p-chlorophenol, TCP and PCP, whereas Type I radical pathway increased. The results obtained for PCP give evidence that electron transfer from the excited sensitiser to the substrate in its unionised form is responsible for enhanced sensitiser photodegradation.
- Full Text:
- Date Issued: 2001
Comparison of extent and transformation of South Africa’s woodland biome from two national databases
- Thompson, M W, Vink, E R, Fairbanks, D H K, Ballance, A, Shackleton, Charlie M
- Authors: Thompson, M W , Vink, E R , Fairbanks, D H K , Ballance, A , Shackleton, Charlie M
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6661 , http://hdl.handle.net/10962/d1007085
- Description: [From introduction] The recent completion of the South African National Land-Cover Database and the Vegetation Map of South Africa, Swaziland and Lesotho, allows for the first time a comparison to be made on a national scale between the current and potential distribution of ‘natural’ vegetation resources. This article compares the distribution and location of woodland-type vegetation categories defined within the National Land-Cover data and the equivalent ‘Savanna-thicket Biomes’ class defined within the Vegetation Mapdata. Significant differences were found, both in terms of the total areal extent, as well as the actual spatial distribution of these two data sets. These differences are a measure of the inherent mapping accuracies of each source, but rather an illustration of boundary delineation distinctions that are a result of different data sources, mapping objectives and information classes, that must be noted when comparing two essentially similar information sets.
- Full Text:
- Date Issued: 2001
Comparison of extent and transformation of South Africa’s woodland biome from two national databases
- Authors: Thompson, M W , Vink, E R , Fairbanks, D H K , Ballance, A , Shackleton, Charlie M
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6661 , http://hdl.handle.net/10962/d1007085
- Description: [From introduction] The recent completion of the South African National Land-Cover Database and the Vegetation Map of South Africa, Swaziland and Lesotho, allows for the first time a comparison to be made on a national scale between the current and potential distribution of ‘natural’ vegetation resources. This article compares the distribution and location of woodland-type vegetation categories defined within the National Land-Cover data and the equivalent ‘Savanna-thicket Biomes’ class defined within the Vegetation Mapdata. Significant differences were found, both in terms of the total areal extent, as well as the actual spatial distribution of these two data sets. These differences are a measure of the inherent mapping accuracies of each source, but rather an illustration of boundary delineation distinctions that are a result of different data sources, mapping objectives and information classes, that must be noted when comparing two essentially similar information sets.
- Full Text:
- Date Issued: 2001
Configuring convergence : southern African websites looking at American experience
- Authors: Berger, Guy
- Date: 2001
- Language: English
- Type: text
- Identifier: vital:535 , http://hdl.handle.net/10962/d1008553 , ISBN 0-86810-379-9
- Description: I want the Web to win. Africa’s news sites on the Internet need to succeed and survive. They’re a small guarantee against global marginalisation, and a critical intersection across our continent’s domestic divides. But the outlook is not good. At a conference I went to in Berkeley in April 2001, a venture capitalist had this to say: "If I were to make a speech on when there’ll be investment in new media again, it would be a rather short topic." The alarming closures and retrenchments at news websites in the USA are sending scary signals to our fledgling efforts back here. Starting and growing media enterprises of any sort in African conditions has never been easy. Long starved of investment, our cyberpublishing now faces even greater pressures as old media – newspapers, radio and TV – try to make ends meet under mounting threats. Advertising is shrinking, local costs are rising and currency falls are fuelling the price of imported production factors. Consumers have less cash to spend. Governments are giving even greater problems in some cases. Will we still be here in the morning, and in what condition? This booklet suggests the way forward is for new media to converge with selected partners, old media and new.
- Full Text:
- Date Issued: 2001
- Authors: Berger, Guy
- Date: 2001
- Language: English
- Type: text
- Identifier: vital:535 , http://hdl.handle.net/10962/d1008553 , ISBN 0-86810-379-9
- Description: I want the Web to win. Africa’s news sites on the Internet need to succeed and survive. They’re a small guarantee against global marginalisation, and a critical intersection across our continent’s domestic divides. But the outlook is not good. At a conference I went to in Berkeley in April 2001, a venture capitalist had this to say: "If I were to make a speech on when there’ll be investment in new media again, it would be a rather short topic." The alarming closures and retrenchments at news websites in the USA are sending scary signals to our fledgling efforts back here. Starting and growing media enterprises of any sort in African conditions has never been easy. Long starved of investment, our cyberpublishing now faces even greater pressures as old media – newspapers, radio and TV – try to make ends meet under mounting threats. Advertising is shrinking, local costs are rising and currency falls are fuelling the price of imported production factors. Consumers have less cash to spend. Governments are giving even greater problems in some cases. Will we still be here in the morning, and in what condition? This booklet suggests the way forward is for new media to converge with selected partners, old media and new.
- Full Text:
- Date Issued: 2001
Confronting the African nightmare: Yael Farber’s SeZaR (theatre review)
- Authors: Wright, Laurence
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:7046 , http://hdl.handle.net/10962/d1007388
- Description: Yael Farber’s adaptation of Julius Caesar marks something of a breakthrough in South African Shakespeare productions. The key achievement is that the play is no longer about Rome or Renaissance England, nor is it about processes of cultural translation or trendy theatrical Africanisation, largely cosmetic. This production is, in a generous way, squarely and pointedly about Africa.
- Full Text:
- Date Issued: 2001
- Authors: Wright, Laurence
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:7046 , http://hdl.handle.net/10962/d1007388
- Description: Yael Farber’s adaptation of Julius Caesar marks something of a breakthrough in South African Shakespeare productions. The key achievement is that the play is no longer about Rome or Renaissance England, nor is it about processes of cultural translation or trendy theatrical Africanisation, largely cosmetic. This production is, in a generous way, squarely and pointedly about Africa.
- Full Text:
- Date Issued: 2001
Consideration of the effect of nutritional status and disease patterns on the work output amongst Black South African workers involved in manual materials handling (MMH) tasks
- Authors: Christie, Candice J
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6746 , http://hdl.handle.net/10962/d1009315
- Description: The prevalence of malnutrition amongst low-income earning South Africans has been well documented and is reported to be particularly high amongst Black South African males. This, combined with poor living conditions associated with their poor socio-economic status, results in an increased prevalence of infectious diseases amongst this sector of the population. Additionally, Black South African males are most often employed by companies requiring them to carry out heavy manual materials handling tasks. It would appear that limited research has focused on the relationship between inadequate dietary intake combined with poor health status and the impact this may have on the performance of manual workers. Energy intake is in all probability considerably less than energy expenditure.
- Full Text:
- Date Issued: 2001
- Authors: Christie, Candice J
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6746 , http://hdl.handle.net/10962/d1009315
- Description: The prevalence of malnutrition amongst low-income earning South Africans has been well documented and is reported to be particularly high amongst Black South African males. This, combined with poor living conditions associated with their poor socio-economic status, results in an increased prevalence of infectious diseases amongst this sector of the population. Additionally, Black South African males are most often employed by companies requiring them to carry out heavy manual materials handling tasks. It would appear that limited research has focused on the relationship between inadequate dietary intake combined with poor health status and the impact this may have on the performance of manual workers. Energy intake is in all probability considerably less than energy expenditure.
- Full Text:
- Date Issued: 2001
Construction and characterization of carbon paste ultra-microelectrodes
- Oni, Joshua, Westbroek, Philippe, Nyokong, Tebello
- Authors: Oni, Joshua , Westbroek, Philippe , Nyokong, Tebello
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/291531 , vital:56884 , xlink:href="https://doi.org/10.1016/S1388-2481(01)00212-0"
- Description: The construction and characterization of carbon paste ultra-microelectrodes is reported. Besides a disc-shaped electrode, a carbon paste band electrode is studied. It was found that for both electrode configurations steady-state currents were obtained but that with the type of electrode material used for the band electrode, the upper limit of ultra-microelectrode dimensions, which could be used was 100–150 μm. Smaller dimensions for the band electrodes resulted in a high resistance due to the limited conductivity of the carbon paste, when using the optimal paste composition. With cyclic voltammetry, the oxidation of [Fe(CN)6]4− was studied at individual constructed electrodes and at ensembles of individual electrodes. Detection limits of less than 10−6moll−1 were obtained. Using the data of the same curves it was possible to test if the electrodes have errors and about 20% of the constructed electrodes did not pass this test. Finally it was found that these electrodes show good stability.
- Full Text:
- Date Issued: 2001
- Authors: Oni, Joshua , Westbroek, Philippe , Nyokong, Tebello
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/291531 , vital:56884 , xlink:href="https://doi.org/10.1016/S1388-2481(01)00212-0"
- Description: The construction and characterization of carbon paste ultra-microelectrodes is reported. Besides a disc-shaped electrode, a carbon paste band electrode is studied. It was found that for both electrode configurations steady-state currents were obtained but that with the type of electrode material used for the band electrode, the upper limit of ultra-microelectrode dimensions, which could be used was 100–150 μm. Smaller dimensions for the band electrodes resulted in a high resistance due to the limited conductivity of the carbon paste, when using the optimal paste composition. With cyclic voltammetry, the oxidation of [Fe(CN)6]4− was studied at individual constructed electrodes and at ensembles of individual electrodes. Detection limits of less than 10−6moll−1 were obtained. Using the data of the same curves it was possible to test if the electrodes have errors and about 20% of the constructed electrodes did not pass this test. Finally it was found that these electrodes show good stability.
- Full Text:
- Date Issued: 2001
Continuity and change in Xhosa historiography during the nineteenth century : an exploration through textual analysis
- Tisani, Nomathamsanqa Cynthia
- Authors: Tisani, Nomathamsanqa Cynthia
- Date: 2001
- Subjects: Xhosa (African people) -- History
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2563 , http://hdl.handle.net/10962/d1002416
- Description: This study is an exploration of the making of Xhosa historiography from the end of the eighteenth century to the close of the nineteenth century. Continuity and change are key features that are identifiable in the writing of Xhosa history over the period. Selected documents provide evidence on how different writers built on the works of their predecessors. At the same time, over a period of hundred years, due to changing socio-political contexts, new ideas and perceptions crept into Xhosa history. European writers, who dominated the writing of Xhosa history, were made up of colonial officials, missionaries, and travellers. Sharing a common European Christian background these writers brought along their particular understanding of history, and held assumptions about the indigenous people and their past. However such assumptions were always in a state of flux. South-east Africans were also major contributors to the making of Xhosa history. Their oral traditions were important sources from which Xhosa history was produced. The African and European encounter in the making of Xhosa history meanHhat historioracy and historiography came together in the production of Xhosa history. At the end of the eighteenth century there were a handful of European travellers who explored the interior of southern Africa and recorded their observations of indigenous communities. These observations of south-east Africans, whom they divided into three racial groups, formed the basis of later writings about the indigenous communiti~s. The beginning of the nineteenth century brought the establishment of British rule at the C,ppe. This introduced new players into the African-European drama that was being acted out on the frontier. Colonial officials set out to inform themselves about the indigenous people, and this meant writing up their history. From the 1820s missionaries were a main source of information on amaXhosa. Xhosa history produced under the missionary influence included works by African converts, among whom Noyi was the most noteworthy. As British imperialism gained ground from the middle of the nineteenth century, history was increasingly used by British officials as a tool to justify their colonial expansion. Under Governor Grey there was a deliberate production of a Xhosa history that depicted amaXhosa as having a barbaric past and in need of civilisation. Theal who consulted Dutch and British archives as well as oral tradition made a major contribution to the writing of Xhosa history. But Theal later began to select evidence to show that amaXhosa were recent immigrants into southeast Africa. During the last quarter ofthe nineteenth century a band of literate Africans, using newspapers like Isigidimi and later Imvo Zabantsundu, embarked on writing African history. This study highlights the development of certain themes in Xhosa history, themes which remained central in later years. The royal theme became pivotal and in the process displaced other histories in African communities, like clan histories. This study has also traced the roots of some historical myths. For example claims by early travellers about an empty land fed into the migration theme which sought to explain amaXhosa as recent immigrants into south-east Africa. Xhosa historiography, just like its European counterpart, marginalised ordinary people, especially women, and became primarily an account of the lives and activities of ruling men.
- Full Text:
- Date Issued: 2001
- Authors: Tisani, Nomathamsanqa Cynthia
- Date: 2001
- Subjects: Xhosa (African people) -- History
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2563 , http://hdl.handle.net/10962/d1002416
- Description: This study is an exploration of the making of Xhosa historiography from the end of the eighteenth century to the close of the nineteenth century. Continuity and change are key features that are identifiable in the writing of Xhosa history over the period. Selected documents provide evidence on how different writers built on the works of their predecessors. At the same time, over a period of hundred years, due to changing socio-political contexts, new ideas and perceptions crept into Xhosa history. European writers, who dominated the writing of Xhosa history, were made up of colonial officials, missionaries, and travellers. Sharing a common European Christian background these writers brought along their particular understanding of history, and held assumptions about the indigenous people and their past. However such assumptions were always in a state of flux. South-east Africans were also major contributors to the making of Xhosa history. Their oral traditions were important sources from which Xhosa history was produced. The African and European encounter in the making of Xhosa history meanHhat historioracy and historiography came together in the production of Xhosa history. At the end of the eighteenth century there were a handful of European travellers who explored the interior of southern Africa and recorded their observations of indigenous communities. These observations of south-east Africans, whom they divided into three racial groups, formed the basis of later writings about the indigenous communiti~s. The beginning of the nineteenth century brought the establishment of British rule at the C,ppe. This introduced new players into the African-European drama that was being acted out on the frontier. Colonial officials set out to inform themselves about the indigenous people, and this meant writing up their history. From the 1820s missionaries were a main source of information on amaXhosa. Xhosa history produced under the missionary influence included works by African converts, among whom Noyi was the most noteworthy. As British imperialism gained ground from the middle of the nineteenth century, history was increasingly used by British officials as a tool to justify their colonial expansion. Under Governor Grey there was a deliberate production of a Xhosa history that depicted amaXhosa as having a barbaric past and in need of civilisation. Theal who consulted Dutch and British archives as well as oral tradition made a major contribution to the writing of Xhosa history. But Theal later began to select evidence to show that amaXhosa were recent immigrants into southeast Africa. During the last quarter ofthe nineteenth century a band of literate Africans, using newspapers like Isigidimi and later Imvo Zabantsundu, embarked on writing African history. This study highlights the development of certain themes in Xhosa history, themes which remained central in later years. The royal theme became pivotal and in the process displaced other histories in African communities, like clan histories. This study has also traced the roots of some historical myths. For example claims by early travellers about an empty land fed into the migration theme which sought to explain amaXhosa as recent immigrants into south-east Africa. Xhosa historiography, just like its European counterpart, marginalised ordinary people, especially women, and became primarily an account of the lives and activities of ruling men.
- Full Text:
- Date Issued: 2001
Credit accessibility and rural development in the former Ciskei: an overview of Keiskammahoek
- Authors: Kimemia, Peter Njau
- Date: 2001
- Subjects: Credit -- Research -- South Africa -- Ciskei , Rural development -- South Africa -- Ciskei , Poor -- South Africa -- Ciskei , Poor -- Developing countries
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3312 , http://hdl.handle.net/10962/d1003100 , Credit -- Research -- South Africa -- Ciskei , Rural development -- South Africa -- Ciskei , Poor -- South Africa -- Ciskei , Poor -- Developing countries
- Description: This study focuses on the issue of credit accessibility for the rural poor. Taking cognisance of the critical role played by innovative micro-lending mechanisms in the sphere of rural development, the study reaffirms the need to enhance access to financial services by rural communities. However, it also reveals the fact that there are numerous impediments to access to credit for the people living in parts of the Keiskammahoek District of the former Ciskei. Key among the impediments has been lack of awareness about the existence and the activities of micro-lending institutions. This has, in a large measure been blamed for many of the rural poor people's failure to approach such institutions for funding. As a result, the affected people's efforts to fully actualize themselves economically have to a certain extent been hampered. Consequently, as its core argument, this study views as crucial the need to tackle all the attendant impediments. It also suggests that as the first step, the government, NGOs as well as formal and informal lending institutions should endeavour to disseminate the requisite information on micro-financing and in enhancing the affected people's institutional capacity to effectively use credit obtained for commercially productive ventures. Without sorting out the basics first, credit extension even when easily availed may not have the desired impact. At worst, it may actually complicate the poverty situation as the people grapple with piling debts.
- Full Text:
- Date Issued: 2001
- Authors: Kimemia, Peter Njau
- Date: 2001
- Subjects: Credit -- Research -- South Africa -- Ciskei , Rural development -- South Africa -- Ciskei , Poor -- South Africa -- Ciskei , Poor -- Developing countries
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3312 , http://hdl.handle.net/10962/d1003100 , Credit -- Research -- South Africa -- Ciskei , Rural development -- South Africa -- Ciskei , Poor -- South Africa -- Ciskei , Poor -- Developing countries
- Description: This study focuses on the issue of credit accessibility for the rural poor. Taking cognisance of the critical role played by innovative micro-lending mechanisms in the sphere of rural development, the study reaffirms the need to enhance access to financial services by rural communities. However, it also reveals the fact that there are numerous impediments to access to credit for the people living in parts of the Keiskammahoek District of the former Ciskei. Key among the impediments has been lack of awareness about the existence and the activities of micro-lending institutions. This has, in a large measure been blamed for many of the rural poor people's failure to approach such institutions for funding. As a result, the affected people's efforts to fully actualize themselves economically have to a certain extent been hampered. Consequently, as its core argument, this study views as crucial the need to tackle all the attendant impediments. It also suggests that as the first step, the government, NGOs as well as formal and informal lending institutions should endeavour to disseminate the requisite information on micro-financing and in enhancing the affected people's institutional capacity to effectively use credit obtained for commercially productive ventures. Without sorting out the basics first, credit extension even when easily availed may not have the desired impact. At worst, it may actually complicate the poverty situation as the people grapple with piling debts.
- Full Text:
- Date Issued: 2001
Cumulative mild head injury in rugby: a comparison of cognitive deficit and postconcussive symptomatology between schoolboy rugby players and non-contact sport controls
- Authors: Beilinsohn, Taryn
- Date: 2001
- Subjects: Rugby football injuries , Head -- Wounds and injuries -- Psychology , Head -- Wounds and injuries -- Complications , Brain damage
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2931 , http://hdl.handle.net/10962/d1002440 , Rugby football injuries , Head -- Wounds and injuries -- Psychology , Head -- Wounds and injuries -- Complications , Brain damage
- Description: This study investigates the cumulative effects of concussive and subconcussive mild head injury on the cognitive functioning of schoolboy rugby players. A comprehensive battery of neuropsychological tests and a self-report postconcussive questionnaire were administered to top level schoolboy rugby players (n=47), and a non-contact sport control group of top level schoolboy hockey players (n=34). Group comparisons of the percentage of individuals with cognitive deficit were carried out between i) the schoolboy rugby and the schoolboy hockey players, ii) the rugby forward and the rugby backline players; iii) the rugby forward and the schoolboy hockey players and, iv) the rugby backline and the schoolboy hockey players. Results on the neuropsychological test battery did not provide any substantial evidence of a higher level of neuropsychological impairment in the rugby players relative to the control group, or in the rugby forward players relative to the rugby backline players. Results obtained on the postconcussive symptom questionnaire provided tentative indications that the rugby players do report a greater frequency of postconcussive symptomatology. The symptoms most frequently reported were being easily angered, memory problems, clumsy speech and sleep difficulties. It was hypothesized that the absence of cognitive impairment in the schoolboy rugby players compared with that noted for professional players was due to their younger age, relatively high IQ and education level and a less intensive level of physical participation in the sport, and hence less accumulated exposure to the game, thereby decreasing their exposure to mild head injuries. From a theoretical perspective, these pre-existing conditions were considered to act as protective factors against reductions in brain reserve capacity and concomitant susceptibility to the onset of neuropsychological dysfunction.
- Full Text:
- Date Issued: 2001
- Authors: Beilinsohn, Taryn
- Date: 2001
- Subjects: Rugby football injuries , Head -- Wounds and injuries -- Psychology , Head -- Wounds and injuries -- Complications , Brain damage
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2931 , http://hdl.handle.net/10962/d1002440 , Rugby football injuries , Head -- Wounds and injuries -- Psychology , Head -- Wounds and injuries -- Complications , Brain damage
- Description: This study investigates the cumulative effects of concussive and subconcussive mild head injury on the cognitive functioning of schoolboy rugby players. A comprehensive battery of neuropsychological tests and a self-report postconcussive questionnaire were administered to top level schoolboy rugby players (n=47), and a non-contact sport control group of top level schoolboy hockey players (n=34). Group comparisons of the percentage of individuals with cognitive deficit were carried out between i) the schoolboy rugby and the schoolboy hockey players, ii) the rugby forward and the rugby backline players; iii) the rugby forward and the schoolboy hockey players and, iv) the rugby backline and the schoolboy hockey players. Results on the neuropsychological test battery did not provide any substantial evidence of a higher level of neuropsychological impairment in the rugby players relative to the control group, or in the rugby forward players relative to the rugby backline players. Results obtained on the postconcussive symptom questionnaire provided tentative indications that the rugby players do report a greater frequency of postconcussive symptomatology. The symptoms most frequently reported were being easily angered, memory problems, clumsy speech and sleep difficulties. It was hypothesized that the absence of cognitive impairment in the schoolboy rugby players compared with that noted for professional players was due to their younger age, relatively high IQ and education level and a less intensive level of physical participation in the sport, and hence less accumulated exposure to the game, thereby decreasing their exposure to mild head injuries. From a theoretical perspective, these pre-existing conditions were considered to act as protective factors against reductions in brain reserve capacity and concomitant susceptibility to the onset of neuropsychological dysfunction.
- Full Text:
- Date Issued: 2001
Deconstructing the Transvaal Supergroup, South Africa: implications for Palaeoproterozoic palaeoclimate models
- Moore, John M, Tsikos, Harilaos, Polteau, S
- Authors: Moore, John M , Tsikos, Harilaos , Polteau, S
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6078 , http://hdl.handle.net/10962/d1006122
- Description: Current correlations between the Pretoria and Postmasburg Groups of the Transvaal Supergroup are shown to be invalid. The Postmasburg Group is also demonstrated to be broadly conformable with the underlying Ghaap Group and therefore considerably older (~2.4 Ga) than previously supposed. The new stratigraphy documents an extensive (100 Ma) and continuous cold-climate episode with a glacial maximum at the Makganyene Formation diamictite. Iron formations of the underlying Asbesheuwels and Koegas Subgroups and overlying Hotazel Formation have similar origins, related, respectively, to the onset and cessation of the glacial event. This interpretation of the Transvaal Supergroup stratigraphy has significant implications for various Palaeoproterozoic environmental models and for the timing of the development of an oxygenated atmosphere.
- Full Text:
- Date Issued: 2001
- Authors: Moore, John M , Tsikos, Harilaos , Polteau, S
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6078 , http://hdl.handle.net/10962/d1006122
- Description: Current correlations between the Pretoria and Postmasburg Groups of the Transvaal Supergroup are shown to be invalid. The Postmasburg Group is also demonstrated to be broadly conformable with the underlying Ghaap Group and therefore considerably older (~2.4 Ga) than previously supposed. The new stratigraphy documents an extensive (100 Ma) and continuous cold-climate episode with a glacial maximum at the Makganyene Formation diamictite. Iron formations of the underlying Asbesheuwels and Koegas Subgroups and overlying Hotazel Formation have similar origins, related, respectively, to the onset and cessation of the glacial event. This interpretation of the Transvaal Supergroup stratigraphy has significant implications for various Palaeoproterozoic environmental models and for the timing of the development of an oxygenated atmosphere.
- Full Text:
- Date Issued: 2001
Design and positioning of controls : the old and the new industrial approaches
- Authors: Dirkse van Schalkwyk, C J
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6750 , http://hdl.handle.net/10962/d1009330
- Description: While copious amounts of research exist with regard to positioning of controls, very little research covers the design shape of the controls. This paper demonstrates the importance of control positioning and design within industrial settings. Furthermore it aims to highlight the changes in industries with regard to control design and positioning. This paper is a review paper and thus much is based on findings by other authors. However, the changes in the industrial practices referred to by the author are from knowledge gained while visiting numerous industries in South Africa.
- Full Text:
- Date Issued: 2001
- Authors: Dirkse van Schalkwyk, C J
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6750 , http://hdl.handle.net/10962/d1009330
- Description: While copious amounts of research exist with regard to positioning of controls, very little research covers the design shape of the controls. This paper demonstrates the importance of control positioning and design within industrial settings. Furthermore it aims to highlight the changes in industries with regard to control design and positioning. This paper is a review paper and thus much is based on findings by other authors. However, the changes in the industrial practices referred to by the author are from knowledge gained while visiting numerous industries in South Africa.
- Full Text:
- Date Issued: 2001
Design, synthesis and characterization of novel rhenium(V) and technetium(V) complexes as potential radiopharmaceuticals
- Authors: Hlabela, Patrick Simon
- Date: 2001
- Subjects: Radiopharmaceuticals , Rhenium , Technetium
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4306 , http://hdl.handle.net/10962/d1004964 , Radiopharmaceuticals , Rhenium , Technetium
- Description: A number of bidentate N, N-diethyl-N' -(R ')benzoylthiourea ligands (where R' = H,CH₃,CI,OCH₃ and N0₂) have been synthesized, as well as the three Re(V) precursor complexes, ReOCl₃(PPh₃)₂,[ReO₂(py)₄]CI and [n-Bu₄N] [ReOCI₄J. The reaction of N,N-diethyl-N'-benzoylthiourea (LH) with these three metal precursor complexes in methanol in the presence of a base gave a novel mixed-ligand complex bis(N,N-diethyl-N'-benzoylthioureato)methoxyoxorhenium(V), [ReO(L)₂(OMe)] (1). In the absence of a base and under an inert atmosphere, the reaction between [n-Bu₄N][ReOCI₄] and LH yielded bis(N,N-diethyl-N'-benzoylthioureato)chlorooxorhenium(V), [ReO(L)₂CI] (lb). The reaction of LH with [ReO₂(py)₄]CI in ethanol and iso-propanol in the presence of sodium acetate gave the novel mixed ligand complexes bis(N,N-diethyl-N'benzoylthioureato) ethoxyoxorhenium(V), [ReO(L)₂(OEt)] (6) and bis(N,N-diethyl-N'benzoylthioureato)(iso-propoxy)oxorhenium(V), [ReO(L)₂(OiPr)] (7), respectively. An oxygen bridged dirhenium complex, [(L)₂0Re-O-ReO(L)₂] (15) was obtained when the reaction was carried out in acetonitrile. A series of mixed ligand Re(V)-oxo complexes using N, N-diethyl-Nʾ-(R' )benzoylthiourea (LR'),N,N-morpholino-N' -(R')benzoylthiourea (morph-LR') and 8-(N-(R')benzoylthiocarbamoyl)-1,4-dioxa-8-azaspiro[4.5]decane ligands (spiro-LR') (where R' = H,CH₃,CI, OCH₃ and N0₂) ((1)(14) have been prepared by the reaction of [ReO₂(py)₄]CI and the ligand in the presence of sodium acetate in methanol. The solution state chemistry of these complexes has shown that complexes(1)-(14) (with the exception of (1b)) undergo dimerization in solution to give complex (15) in the presence of water. Preliminary ¹H NMR kinetics studies of the dimerization of (1), (6) and (7) to (15) have shown that the rate of dimerization decreases in the order (7) > (6) > (1). The rate of dimerization has also been compared for complexes (1), [ReO(morph-L)₂(OMe)] (8) and [ReO(spiro-L)₂(OMe)] (13) and the rate of dimerization was found to be fastest for (13). The crystal structures of (1), [ReO(LN0₂)₂(OMe)] (4), (6) and (15) have been determined. The Re(V)-oxo complexes (1), (4) and (6) have a slightly distorted octahedral geometry with the two acylthiourea ligands binding in a cis arrangement in the equatorial plane of the octahedron. The alkoxy and oxo ligands occupy the axial positions and are situated trans to each other. The crystal and molecular structure of complex (15), consist of two slightly distorted octahedral [ReO(L)₂] moieties bridged by an oxygen atom with a Re-O-Re bond angle of 175.2(2)°. The preliminary studies done in the present study have indicated that the complexation chemistry of technetium(V) with the N,N-diethyl-benzoylthiourea is different to that of rhenium (V). The reaction between [n-BuN₄][TcOCl₄] and N,N-diethyl-N'-benzoylthiourea yielded the square pyramidal cationic complex [TcO(L)₂]Cl. By contrast the octahedral methoxy complex [ReO(L )₂( OMe)] was obtained when the analogous Re(V)-oxo precursor, [n-Bu₄N] [ReOCI₄], was reacted with N,N-diethyl-N'-benzoylthiourea under the same reaction conditions.
- Full Text:
- Date Issued: 2001
- Authors: Hlabela, Patrick Simon
- Date: 2001
- Subjects: Radiopharmaceuticals , Rhenium , Technetium
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4306 , http://hdl.handle.net/10962/d1004964 , Radiopharmaceuticals , Rhenium , Technetium
- Description: A number of bidentate N, N-diethyl-N' -(R ')benzoylthiourea ligands (where R' = H,CH₃,CI,OCH₃ and N0₂) have been synthesized, as well as the three Re(V) precursor complexes, ReOCl₃(PPh₃)₂,[ReO₂(py)₄]CI and [n-Bu₄N] [ReOCI₄J. The reaction of N,N-diethyl-N'-benzoylthiourea (LH) with these three metal precursor complexes in methanol in the presence of a base gave a novel mixed-ligand complex bis(N,N-diethyl-N'-benzoylthioureato)methoxyoxorhenium(V), [ReO(L)₂(OMe)] (1). In the absence of a base and under an inert atmosphere, the reaction between [n-Bu₄N][ReOCI₄] and LH yielded bis(N,N-diethyl-N'-benzoylthioureato)chlorooxorhenium(V), [ReO(L)₂CI] (lb). The reaction of LH with [ReO₂(py)₄]CI in ethanol and iso-propanol in the presence of sodium acetate gave the novel mixed ligand complexes bis(N,N-diethyl-N'benzoylthioureato) ethoxyoxorhenium(V), [ReO(L)₂(OEt)] (6) and bis(N,N-diethyl-N'benzoylthioureato)(iso-propoxy)oxorhenium(V), [ReO(L)₂(OiPr)] (7), respectively. An oxygen bridged dirhenium complex, [(L)₂0Re-O-ReO(L)₂] (15) was obtained when the reaction was carried out in acetonitrile. A series of mixed ligand Re(V)-oxo complexes using N, N-diethyl-Nʾ-(R' )benzoylthiourea (LR'),N,N-morpholino-N' -(R')benzoylthiourea (morph-LR') and 8-(N-(R')benzoylthiocarbamoyl)-1,4-dioxa-8-azaspiro[4.5]decane ligands (spiro-LR') (where R' = H,CH₃,CI, OCH₃ and N0₂) ((1)(14) have been prepared by the reaction of [ReO₂(py)₄]CI and the ligand in the presence of sodium acetate in methanol. The solution state chemistry of these complexes has shown that complexes(1)-(14) (with the exception of (1b)) undergo dimerization in solution to give complex (15) in the presence of water. Preliminary ¹H NMR kinetics studies of the dimerization of (1), (6) and (7) to (15) have shown that the rate of dimerization decreases in the order (7) > (6) > (1). The rate of dimerization has also been compared for complexes (1), [ReO(morph-L)₂(OMe)] (8) and [ReO(spiro-L)₂(OMe)] (13) and the rate of dimerization was found to be fastest for (13). The crystal structures of (1), [ReO(LN0₂)₂(OMe)] (4), (6) and (15) have been determined. The Re(V)-oxo complexes (1), (4) and (6) have a slightly distorted octahedral geometry with the two acylthiourea ligands binding in a cis arrangement in the equatorial plane of the octahedron. The alkoxy and oxo ligands occupy the axial positions and are situated trans to each other. The crystal and molecular structure of complex (15), consist of two slightly distorted octahedral [ReO(L)₂] moieties bridged by an oxygen atom with a Re-O-Re bond angle of 175.2(2)°. The preliminary studies done in the present study have indicated that the complexation chemistry of technetium(V) with the N,N-diethyl-benzoylthiourea is different to that of rhenium (V). The reaction between [n-BuN₄][TcOCl₄] and N,N-diethyl-N'-benzoylthiourea yielded the square pyramidal cationic complex [TcO(L)₂]Cl. By contrast the octahedral methoxy complex [ReO(L )₂( OMe)] was obtained when the analogous Re(V)-oxo precursor, [n-Bu₄N] [ReOCI₄], was reacted with N,N-diethyl-N'-benzoylthiourea under the same reaction conditions.
- Full Text:
- Date Issued: 2001
Design, synthesis and evaluation of silver-specific ligands
- Authors: Daubinet, André
- Date: 2001
- Subjects: Ligands Ligands -- Design Ligands -- Analysis Ligands -- Evaluation Silver -- Metallurgy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4308 , http://hdl.handle.net/10962/d1004966
- Description: Several series of ligands, designed to chelate silver(I) specifically in the presence of base metals, have been synthesised. The ligands include: - dithiodiamide compounds, prepared by the condensation of acetanilide derivatives with 1,2-dibromoethane; propanenitrile and propanoic ester derivatives prepared from pyridine-2-carbaldehyde via the Morita-Baylis-Hillman reaction; and novel malonamide ligands from the reaction of diethyl malonate with a range of primary amines. The malonamide derivatives were prepared under both conventional thermal and microwave-assisted conditions, the latter proving to be highly efficient. The ligands were all characterised using a combination of spectroscopic and, where appropriate, elemental analysis; in one case, the structural assignment was confirmed by single-crystal X-ray analysis. The fragmentation patterns in the electron-impact mass spectra of the malonamide derivatives have been explored using high-resolution and meta-stable peak scanning techniques. Complexes of the malonamide ligands with copper(II) and silver(I) have been synthesised, and examination of these complexes has revealed distinct differences in their co-ordination preferences towards silver(I) and copper(II). Tentative, computer-modelled structures for the complexes have been proposed using the available spectroscopic and elemental analysis data. Computer modelling, at the Molecular Mechanics level, has also been used to assess the capacity of the ligand systems to adopt conformations suitable for the chelation of tetrahedral silver(I). Solvent extraction studies have been undertaken using aqueous metal ion solutions and various organic solvents. The dithiodiamide derivatives typically presented solubility problems, but one of the ligands, N,N´-bis(3-chlorophenyl)-3,6-dithiaoctanediamide, exhibited significant but slow extraction of silver(I) into toluene. The malonamide derivatives, however, proved to be readily soluble in ethyl acetate and, in some cases, exhibited good to excellent selectivity for silver(I) in the presence of the base metals copper and lead. Atomic absorption analysis revealed rapid equilibration times (<15 min) and high extraction efficiencies over a wide pH range (2.78 - 9.0). Metal selectivity has been determined by ICP-MS analysis of the residual silver, copper and lead present in the aqueous phase after 15 min, and one of the ligands, N,N´-bis(2-benzylsulfanylethyl)malonamide, exhibits excellent (≥ 96 %) silver(I) specificity.
- Full Text:
- Date Issued: 2001
- Authors: Daubinet, André
- Date: 2001
- Subjects: Ligands Ligands -- Design Ligands -- Analysis Ligands -- Evaluation Silver -- Metallurgy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4308 , http://hdl.handle.net/10962/d1004966
- Description: Several series of ligands, designed to chelate silver(I) specifically in the presence of base metals, have been synthesised. The ligands include: - dithiodiamide compounds, prepared by the condensation of acetanilide derivatives with 1,2-dibromoethane; propanenitrile and propanoic ester derivatives prepared from pyridine-2-carbaldehyde via the Morita-Baylis-Hillman reaction; and novel malonamide ligands from the reaction of diethyl malonate with a range of primary amines. The malonamide derivatives were prepared under both conventional thermal and microwave-assisted conditions, the latter proving to be highly efficient. The ligands were all characterised using a combination of spectroscopic and, where appropriate, elemental analysis; in one case, the structural assignment was confirmed by single-crystal X-ray analysis. The fragmentation patterns in the electron-impact mass spectra of the malonamide derivatives have been explored using high-resolution and meta-stable peak scanning techniques. Complexes of the malonamide ligands with copper(II) and silver(I) have been synthesised, and examination of these complexes has revealed distinct differences in their co-ordination preferences towards silver(I) and copper(II). Tentative, computer-modelled structures for the complexes have been proposed using the available spectroscopic and elemental analysis data. Computer modelling, at the Molecular Mechanics level, has also been used to assess the capacity of the ligand systems to adopt conformations suitable for the chelation of tetrahedral silver(I). Solvent extraction studies have been undertaken using aqueous metal ion solutions and various organic solvents. The dithiodiamide derivatives typically presented solubility problems, but one of the ligands, N,N´-bis(3-chlorophenyl)-3,6-dithiaoctanediamide, exhibited significant but slow extraction of silver(I) into toluene. The malonamide derivatives, however, proved to be readily soluble in ethyl acetate and, in some cases, exhibited good to excellent selectivity for silver(I) in the presence of the base metals copper and lead. Atomic absorption analysis revealed rapid equilibration times (<15 min) and high extraction efficiencies over a wide pH range (2.78 - 9.0). Metal selectivity has been determined by ICP-MS analysis of the residual silver, copper and lead present in the aqueous phase after 15 min, and one of the ligands, N,N´-bis(2-benzylsulfanylethyl)malonamide, exhibits excellent (≥ 96 %) silver(I) specificity.
- Full Text:
- Date Issued: 2001