The ataxia protein sacsin is a functional co-chaperone that protects against polyglutamine-expanded ataxin-1
- Parfitt, David A, Michael, Gregory J, Vermeulen, Esmeralda G M, Prodromou, Natalia V, Webb, Tom R, Gallo, Jean-Marc, Cheetham, Michael E, Nicoll, William S, Blatch, Gregory L, Chapple, J Paul
- Authors: Parfitt, David A , Michael, Gregory J , Vermeulen, Esmeralda G M , Prodromou, Natalia V , Webb, Tom R , Gallo, Jean-Marc , Cheetham, Michael E , Nicoll, William S , Blatch, Gregory L , Chapple, J Paul
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6485 , http://hdl.handle.net/10962/d1006262 , http://hmg.oxfordjournals.org/content/18/9/1556
- Description: An extensive protein–protein interaction network has been identified between proteins implicated in inherited ataxias. The protein sacsin, which is mutated in the early-onset neurodegenerative disease autosomal recessive spastic ataxia of Charlevoix-Saguenay, is a node in this interactome. Here, we have established the neuronal expression of sacsin and functionally characterized domains of the 4579 amino acid protein. Sacsin is most highly expressed in large neurons, particularly within brain motor systems, including cerebellar Purkinje cells. Its subcellular localization in SH-SY5Y neuroblastoma cells was predominantly cytoplasmic with a mitochondrial component. We identified a putative ubiquitin-like (UbL) domain at the N-terminus of sacsin and demonstrated an interaction with the proteasome. Furthermore, sacsin contains a predicted J-domain, the defining feature of DnaJ/Hsp40 proteins. Using a bacterial complementation assay, the sacsin J-domain was demonstrated to be functional. The presence of both UbL and J-domains in sacsin suggests that it may integrate the ubiquitin–proteasome system and Hsp70 function to a specific cellular role. The Hsp70 chaperone machinery is an important component of the cellular response towards aggregation prone mutant proteins that are associated with neurodegenerative diseases. We therefore investigated the effects of siRNA-mediated sacsin knockdown on polyglutamine-expanded ataxin-1. Importantly, SACS siRNA did not affect cell viability with GFP-ataxin-1[30Q], but enhanced the toxicity of GFP-ataxin- 1[82Q], suggesting that sacsin is protective against mutant ataxin-1. Thus, sacsin is an ataxia protein and a regulator of the Hsp70 chaperone machinery that is implicated in the processing of other ataxialinked proteins.
- Full Text:
- Date Issued: 2009
- Authors: Parfitt, David A , Michael, Gregory J , Vermeulen, Esmeralda G M , Prodromou, Natalia V , Webb, Tom R , Gallo, Jean-Marc , Cheetham, Michael E , Nicoll, William S , Blatch, Gregory L , Chapple, J Paul
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6485 , http://hdl.handle.net/10962/d1006262 , http://hmg.oxfordjournals.org/content/18/9/1556
- Description: An extensive protein–protein interaction network has been identified between proteins implicated in inherited ataxias. The protein sacsin, which is mutated in the early-onset neurodegenerative disease autosomal recessive spastic ataxia of Charlevoix-Saguenay, is a node in this interactome. Here, we have established the neuronal expression of sacsin and functionally characterized domains of the 4579 amino acid protein. Sacsin is most highly expressed in large neurons, particularly within brain motor systems, including cerebellar Purkinje cells. Its subcellular localization in SH-SY5Y neuroblastoma cells was predominantly cytoplasmic with a mitochondrial component. We identified a putative ubiquitin-like (UbL) domain at the N-terminus of sacsin and demonstrated an interaction with the proteasome. Furthermore, sacsin contains a predicted J-domain, the defining feature of DnaJ/Hsp40 proteins. Using a bacterial complementation assay, the sacsin J-domain was demonstrated to be functional. The presence of both UbL and J-domains in sacsin suggests that it may integrate the ubiquitin–proteasome system and Hsp70 function to a specific cellular role. The Hsp70 chaperone machinery is an important component of the cellular response towards aggregation prone mutant proteins that are associated with neurodegenerative diseases. We therefore investigated the effects of siRNA-mediated sacsin knockdown on polyglutamine-expanded ataxin-1. Importantly, SACS siRNA did not affect cell viability with GFP-ataxin-1[30Q], but enhanced the toxicity of GFP-ataxin- 1[82Q], suggesting that sacsin is protective against mutant ataxin-1. Thus, sacsin is an ataxia protein and a regulator of the Hsp70 chaperone machinery that is implicated in the processing of other ataxialinked proteins.
- Full Text:
- Date Issued: 2009
The attitudes and perceptions of students at a South African university towards binge drinking
- Authors: Mokgethi, Lerato
- Date: 2009
- Subjects: College students -- Alcohol use -- South Africa , Alcoholism -- Treatment -- South Africa , Drug abuse -- Treatment -- South Africa , Binge drinking
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9858 , http://hdl.handle.net/10948/1560 , College students -- Alcohol use -- South Africa , Alcoholism -- Treatment -- South Africa , Drug abuse -- Treatment -- South Africa , Binge drinking
- Description: The focus of this treatise is to explore the attitudes and perceptions of university students towards binge drinking at a South African University. Binge drinking among university students is a serious concern, prevalent on many campuses and ingrained on university campuses worldwide. The aims of this study were (a) to describe students’ understanding of binge drinking, (b) to explore and describe university students’ attitudes towards and perceptions of binge drinking, and (c) to explore the contextual factors relating to binge drinking within a university setting. An exploratory, qualitative approach was utilized. The collection of data was initiated using a biographical questionnaire to identify participants relevant to the study. The data collection process continued with semi‐structured focus group interviews. Data was collected by conducting four focus group sessions with two separate groups of students between the ages of 18 and 25 and residing on a university campus. Data analysis was conducted in accordance with the principles and guidelines of Tesch’s (as cited in Creswell, 1994) eight steps in qualitative data analysis. The results of this study indicate the following: there is lack of knowledge and understanding of binge drinking, students have positive perceptions of binge drinking and there is a perception that the university environment promotes binge drinking. In order to address binge drinking, strategies need to be implemented in the student, family, university and community context.
- Full Text:
- Date Issued: 2009
- Authors: Mokgethi, Lerato
- Date: 2009
- Subjects: College students -- Alcohol use -- South Africa , Alcoholism -- Treatment -- South Africa , Drug abuse -- Treatment -- South Africa , Binge drinking
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9858 , http://hdl.handle.net/10948/1560 , College students -- Alcohol use -- South Africa , Alcoholism -- Treatment -- South Africa , Drug abuse -- Treatment -- South Africa , Binge drinking
- Description: The focus of this treatise is to explore the attitudes and perceptions of university students towards binge drinking at a South African University. Binge drinking among university students is a serious concern, prevalent on many campuses and ingrained on university campuses worldwide. The aims of this study were (a) to describe students’ understanding of binge drinking, (b) to explore and describe university students’ attitudes towards and perceptions of binge drinking, and (c) to explore the contextual factors relating to binge drinking within a university setting. An exploratory, qualitative approach was utilized. The collection of data was initiated using a biographical questionnaire to identify participants relevant to the study. The data collection process continued with semi‐structured focus group interviews. Data was collected by conducting four focus group sessions with two separate groups of students between the ages of 18 and 25 and residing on a university campus. Data analysis was conducted in accordance with the principles and guidelines of Tesch’s (as cited in Creswell, 1994) eight steps in qualitative data analysis. The results of this study indicate the following: there is lack of knowledge and understanding of binge drinking, students have positive perceptions of binge drinking and there is a perception that the university environment promotes binge drinking. In order to address binge drinking, strategies need to be implemented in the student, family, university and community context.
- Full Text:
- Date Issued: 2009
The binding roots of free speech
- Authors: Boughey, Thomas John George
- Date: 2009
- Subjects: Freedom of speech
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2849 , http://hdl.handle.net/10962/d1006255
- Description: This thesis argues that the modern notion of free-speech was born within the Westphalian nation-state. It suggests that the legal rights framework - particular to the Westphalian nationstate - not only legitimizes and legalizes the right to free-speech, but also enables us to invoke legally the necessary limitations that demand the limitation of free-speech in certain contexts. However, such a legal-rights framework is exclusive to the nation-state and cannot be enforced on an international level, outside of the nation-state boundary. With reference to examples on an international level, this thesis demonstrates that calls for the limitation of free-speech are indeed legitimate and necessary but cannot be enforced on an international level for the reasons just mentioned. In order to address this problem, this thesis proposes a framework - based on a Kantian model - that enables us to invoke the limitation of free-speech on an international level without appealing to a legal-rights discourse to do so.
- Full Text:
- Date Issued: 2009
- Authors: Boughey, Thomas John George
- Date: 2009
- Subjects: Freedom of speech
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2849 , http://hdl.handle.net/10962/d1006255
- Description: This thesis argues that the modern notion of free-speech was born within the Westphalian nation-state. It suggests that the legal rights framework - particular to the Westphalian nationstate - not only legitimizes and legalizes the right to free-speech, but also enables us to invoke legally the necessary limitations that demand the limitation of free-speech in certain contexts. However, such a legal-rights framework is exclusive to the nation-state and cannot be enforced on an international level, outside of the nation-state boundary. With reference to examples on an international level, this thesis demonstrates that calls for the limitation of free-speech are indeed legitimate and necessary but cannot be enforced on an international level for the reasons just mentioned. In order to address this problem, this thesis proposes a framework - based on a Kantian model - that enables us to invoke the limitation of free-speech on an international level without appealing to a legal-rights discourse to do so.
- Full Text:
- Date Issued: 2009
The both-and edition:
- Authors: Garman, Anthea
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/158817 , vital:40231 , https://hdl.handle.net/10520/EJC139955
- Description: I was driving down the N2 from Cape Town towards the airport recently and scanning the turn-offs for Vanguard Drive, when suddenly I noticed among the shacks that line the road some really interesting buildings. These were not the pale pink matchboxes that periodically spring up in rows alongside the derelict housing that millions of South Africans call home. They were multi-levelled, had large windows and looked like an architect might have had something to do with them. I was heartened at the sight of housing – at last – with humanity in mind. But as I reread the 2010 pieces in this edition, I’m reminded by Jane Duncan in particular (“Whose World Cup?” page 23) that prettifying the ghastly spaces in our world cup cities that will be visible to those international tourists is high on the agenda for our government. But then, I reason, at least someone will benefit from living along the noisy and congested airport route!.
- Full Text:
- Date Issued: 2009
- Authors: Garman, Anthea
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/158817 , vital:40231 , https://hdl.handle.net/10520/EJC139955
- Description: I was driving down the N2 from Cape Town towards the airport recently and scanning the turn-offs for Vanguard Drive, when suddenly I noticed among the shacks that line the road some really interesting buildings. These were not the pale pink matchboxes that periodically spring up in rows alongside the derelict housing that millions of South Africans call home. They were multi-levelled, had large windows and looked like an architect might have had something to do with them. I was heartened at the sight of housing – at last – with humanity in mind. But as I reread the 2010 pieces in this edition, I’m reminded by Jane Duncan in particular (“Whose World Cup?” page 23) that prettifying the ghastly spaces in our world cup cities that will be visible to those international tourists is high on the agenda for our government. But then, I reason, at least someone will benefit from living along the noisy and congested airport route!.
- Full Text:
- Date Issued: 2009
The capacity of emerging civil engineering construction contractors
- Ramokolo, Bruce Sabelo Mpumelelo
- Authors: Ramokolo, Bruce Sabelo Mpumelelo
- Date: 2009
- Subjects: Civil engineering -- Contracts -- South Africa -- Port Elizabeth , Construction industry -- South Africa -- Port Elizabeth -- Management , Construction contracts -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9693 , http://hdl.handle.net/10948/873 , Civil engineering -- Contracts -- South Africa -- Port Elizabeth , Construction industry -- South Africa -- Port Elizabeth -- Management , Construction contracts -- South Africa -- Port Elizabeth
- Description: Construction management competencies are essential to realise sound practices among and to realise optimum performance by, inter alia, emerging civil engineering contractors. Such competencies enable a clear focus on the business of construction and the management of projects, with increased efficiency and reduced costs as a benefit. The objective of the MSc (Built Environment) treatise study were to determine the current practices and performance of emerging civil engineering construction contractors operating in the Nelson Mandela Bay Metropole. The descriptive method was adopted in the empirical study. The salient findings of the study are: most of the emerging civil engineering construction contracting organisations lack construction management competencies; construction resources are inappropriately managed leading to construction failures; most of the emerging civil engineering construction contracting organisations lack adequate supervision resulting to poor workmanship; there is a shortage of skilled labour amongst emerging civil engineering construction contractors; procurement processes are inappropriate leading to under capacitated emerging civil engineering construction contracting organisations being awarded contracts; most emerging civil engineering construction contracting organisations lack the requisite aptitude for construction; there is a lack of capacity at all management levels of emerging civil engineering construction organisations in managing the business of construction and that of projects; the nine functions of organisations are not comprehensively represented, and self-ratings indicate inadequacy relative to the management function of control, and relative to certain activities of the organising function. Conclusions include that emerging civil engineering construction contracting organisations need to be comprised of technical teams that possess adequate competencies and that use the construction technology to its full use enabling their organisations to stay abreast of their competitors. Recommendations that can contribute towards improving the status quo include: formal civil engineering and construction management education, resources must be present and training should be promoted throughout the industry at all levels of management to ensure proper supervision and correct use of adequately trained labour, skilled or semi-skilled, incapacitated emerging civil engineering construction contractors should be awarded contracts through appropriately and structured procurement procedures, adequate aptitude in construction should be promoted and enhanced in order to realise conceptualisation and visualisation capabilities, comply with legislation, maintain records and communicate using state of the art technology, optimally manage the finances, have the requisite resources and undertake the work efficiently, interact with the respective publics, and market the organisation to ensure sustainability thereof.
- Full Text:
- Date Issued: 2009
- Authors: Ramokolo, Bruce Sabelo Mpumelelo
- Date: 2009
- Subjects: Civil engineering -- Contracts -- South Africa -- Port Elizabeth , Construction industry -- South Africa -- Port Elizabeth -- Management , Construction contracts -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9693 , http://hdl.handle.net/10948/873 , Civil engineering -- Contracts -- South Africa -- Port Elizabeth , Construction industry -- South Africa -- Port Elizabeth -- Management , Construction contracts -- South Africa -- Port Elizabeth
- Description: Construction management competencies are essential to realise sound practices among and to realise optimum performance by, inter alia, emerging civil engineering contractors. Such competencies enable a clear focus on the business of construction and the management of projects, with increased efficiency and reduced costs as a benefit. The objective of the MSc (Built Environment) treatise study were to determine the current practices and performance of emerging civil engineering construction contractors operating in the Nelson Mandela Bay Metropole. The descriptive method was adopted in the empirical study. The salient findings of the study are: most of the emerging civil engineering construction contracting organisations lack construction management competencies; construction resources are inappropriately managed leading to construction failures; most of the emerging civil engineering construction contracting organisations lack adequate supervision resulting to poor workmanship; there is a shortage of skilled labour amongst emerging civil engineering construction contractors; procurement processes are inappropriate leading to under capacitated emerging civil engineering construction contracting organisations being awarded contracts; most emerging civil engineering construction contracting organisations lack the requisite aptitude for construction; there is a lack of capacity at all management levels of emerging civil engineering construction organisations in managing the business of construction and that of projects; the nine functions of organisations are not comprehensively represented, and self-ratings indicate inadequacy relative to the management function of control, and relative to certain activities of the organising function. Conclusions include that emerging civil engineering construction contracting organisations need to be comprised of technical teams that possess adequate competencies and that use the construction technology to its full use enabling their organisations to stay abreast of their competitors. Recommendations that can contribute towards improving the status quo include: formal civil engineering and construction management education, resources must be present and training should be promoted throughout the industry at all levels of management to ensure proper supervision and correct use of adequately trained labour, skilled or semi-skilled, incapacitated emerging civil engineering construction contractors should be awarded contracts through appropriately and structured procurement procedures, adequate aptitude in construction should be promoted and enhanced in order to realise conceptualisation and visualisation capabilities, comply with legislation, maintain records and communicate using state of the art technology, optimally manage the finances, have the requisite resources and undertake the work efficiently, interact with the respective publics, and market the organisation to ensure sustainability thereof.
- Full Text:
- Date Issued: 2009
The challenges of education and development in twenty-first century South Africa
- Authors: Badat, Saleem
- Date: 2009
- Language: English
- Type: Conference paper , text
- Identifier: vital:7121 , http://hdl.handle.net/10962/d1006569
- Description: From the introduction: I have chosen to address the theme of The Challenges of Education and Development in the Twenty First Century. This is not only an extremely important theme but also one that is both complex and broad and can be approached in many different ways. With respect to complexity, the concepts of education and development, like the concepts of freedom and democracy, are defined in various ways and have a variety of meanings associated with them. Moreover, notions of education and development are not neutral in that they are embedded in different views of the world and society, including views on what constitutes a just and good society. Further, the choices, policies, actions and practices that are associated with particular conceptions of education and development are not benign in that they have real and differential effects on different social classes and groups in society. , Keynote Address at the 15th Annual Conference of the Headmasters of the Traditional State Boy’s Schools of South Africa’ Queens College, Queenstown, 26 August 2009.
- Full Text:
- Date Issued: 2009
- Authors: Badat, Saleem
- Date: 2009
- Language: English
- Type: Conference paper , text
- Identifier: vital:7121 , http://hdl.handle.net/10962/d1006569
- Description: From the introduction: I have chosen to address the theme of The Challenges of Education and Development in the Twenty First Century. This is not only an extremely important theme but also one that is both complex and broad and can be approached in many different ways. With respect to complexity, the concepts of education and development, like the concepts of freedom and democracy, are defined in various ways and have a variety of meanings associated with them. Moreover, notions of education and development are not neutral in that they are embedded in different views of the world and society, including views on what constitutes a just and good society. Further, the choices, policies, actions and practices that are associated with particular conceptions of education and development are not benign in that they have real and differential effects on different social classes and groups in society. , Keynote Address at the 15th Annual Conference of the Headmasters of the Traditional State Boy’s Schools of South Africa’ Queens College, Queenstown, 26 August 2009.
- Full Text:
- Date Issued: 2009
The choice of idols from a social psychological perspective
- Authors: Lupke, Lynette M
- Date: 2009
- Subjects: Identity (Psychology) , Idols and images , Social interaction
- Language: English
- Type: Thesis , Masters , M Soc Sc (Psych)
- Identifier: vital:11606 , http://hdl.handle.net/10353/132 , Identity (Psychology) , Idols and images , Social interaction
- Description: The study of adolescents’ idols has an over 100-year tradition. The meta-analysis of Teigen, Normann, Bjorkheim and Helland (2000) showed that idols, which are commonly understood as role models, changed over the last century which is attributed to changes in the social context. The present paper argues that Social Identity Theory (Tajfel & Turner, 1979, 1986) offers an appropriate theoretical framework to conceptualize social context by hypothesising a functional relationship between idols and identity management strategies moderated by the status position of the adolescent’s group s/he belongs to. The hypothesised functional relationship was tested in two studies with white and black adolescent South Africans. The results of the two studies supported our assumptions that the functional relationship between idols and identity management strategies is indeed moderated by status position. The results also indicate that Social Identity Theory seems to be an appropriate theoretical framework when social context is particularly conceptualised as social change.
- Full Text:
- Date Issued: 2009
- Authors: Lupke, Lynette M
- Date: 2009
- Subjects: Identity (Psychology) , Idols and images , Social interaction
- Language: English
- Type: Thesis , Masters , M Soc Sc (Psych)
- Identifier: vital:11606 , http://hdl.handle.net/10353/132 , Identity (Psychology) , Idols and images , Social interaction
- Description: The study of adolescents’ idols has an over 100-year tradition. The meta-analysis of Teigen, Normann, Bjorkheim and Helland (2000) showed that idols, which are commonly understood as role models, changed over the last century which is attributed to changes in the social context. The present paper argues that Social Identity Theory (Tajfel & Turner, 1979, 1986) offers an appropriate theoretical framework to conceptualize social context by hypothesising a functional relationship between idols and identity management strategies moderated by the status position of the adolescent’s group s/he belongs to. The hypothesised functional relationship was tested in two studies with white and black adolescent South Africans. The results of the two studies supported our assumptions that the functional relationship between idols and identity management strategies is indeed moderated by status position. The results also indicate that Social Identity Theory seems to be an appropriate theoretical framework when social context is particularly conceptualised as social change.
- Full Text:
- Date Issued: 2009
The consequences of unlawful and prohibited contracts of employment in labour law
- Authors: Salim, Raya Said
- Date: 2009
- Subjects: Contracts for work and labor -- South Africa , Labor contract -- South Africa , Labor laws and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10222 , http://hdl.handle.net/10948/1041 , Contracts for work and labor -- South Africa , Labor contract -- South Africa , Labor laws and legislation -- South Africa
- Description: The purpose of having labour laws in South Africa is to regulate employment contracts and the relationship between the employer and the employee. Once a legally binding contract comes into being the Labour Relations Act of 1995 automatically applies alongside the Basic Conditions of Employment Act and various other labour legislations. Common law rules play a vital role in the formation of an employment contract. For an ordinary contract to have legal effect, four basic requirements need to be met. Briefly, parties to the contract must have reached consensus, parties’ performance of their obligations must be possible, the conclusion and objectives of the contract must be lawful and that both parties to the contract must have the necessary capacity to conclude the contract. Once these requirements have been met one is said to have concluded a valid contract. Nevertheless for the purposes of this study, we focus specifically on the employment contract. Aside from the general common law requirements for a valid contract, for an employment contract to be recognised and protected by labour legislations, it is important to distinguish an employee from an independent contractor since only the former enjoys legal remedies afforded by labour law. Common law contractual rights and duties automatically apply once an employment relationship is established in addition to the rights and duties specified in the contract itself. Common law rules regarding morality plays a major role in our modern day societies, as shall be discussed the workforce has not been left untouched by this important principle. Morality greatly influences a society’s view concerning acceptable and unacceptable behaviour or practices. It goes without saying that a contract should not be contrary to the moral views of the society in which the parties find themselves in. A contract can be complying with all the statutory requirements for a valid employment contract; however it may at the same time be tainted with illegality as the object of performance is considered immoral in the society such as an employment contract to perform prostitution. Conversely, another scenario may involve a party to an employment contract who is a child below the age of 15 years old; the contract is invalid as it contravenes section 43 of the Basic Conditions of Employment Act. Despite clear statutory prohibitions this practice may be perfectly acceptable in the eyes and minds of the society. The purpose of this study is to evaluate prohibited and unlawful contracts of employments, how the law (both common law and statutory law) treats such contracts in the sense that; whether they are protected or not and to what extent these laws have been developed to influence modern attitudes concerning such contracts. One stark example is illustrated through case law where the court had to determine the validity of an employment contract concluded between an employer and an illegal immigrant.
- Full Text:
- Date Issued: 2009
- Authors: Salim, Raya Said
- Date: 2009
- Subjects: Contracts for work and labor -- South Africa , Labor contract -- South Africa , Labor laws and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10222 , http://hdl.handle.net/10948/1041 , Contracts for work and labor -- South Africa , Labor contract -- South Africa , Labor laws and legislation -- South Africa
- Description: The purpose of having labour laws in South Africa is to regulate employment contracts and the relationship between the employer and the employee. Once a legally binding contract comes into being the Labour Relations Act of 1995 automatically applies alongside the Basic Conditions of Employment Act and various other labour legislations. Common law rules play a vital role in the formation of an employment contract. For an ordinary contract to have legal effect, four basic requirements need to be met. Briefly, parties to the contract must have reached consensus, parties’ performance of their obligations must be possible, the conclusion and objectives of the contract must be lawful and that both parties to the contract must have the necessary capacity to conclude the contract. Once these requirements have been met one is said to have concluded a valid contract. Nevertheless for the purposes of this study, we focus specifically on the employment contract. Aside from the general common law requirements for a valid contract, for an employment contract to be recognised and protected by labour legislations, it is important to distinguish an employee from an independent contractor since only the former enjoys legal remedies afforded by labour law. Common law contractual rights and duties automatically apply once an employment relationship is established in addition to the rights and duties specified in the contract itself. Common law rules regarding morality plays a major role in our modern day societies, as shall be discussed the workforce has not been left untouched by this important principle. Morality greatly influences a society’s view concerning acceptable and unacceptable behaviour or practices. It goes without saying that a contract should not be contrary to the moral views of the society in which the parties find themselves in. A contract can be complying with all the statutory requirements for a valid employment contract; however it may at the same time be tainted with illegality as the object of performance is considered immoral in the society such as an employment contract to perform prostitution. Conversely, another scenario may involve a party to an employment contract who is a child below the age of 15 years old; the contract is invalid as it contravenes section 43 of the Basic Conditions of Employment Act. Despite clear statutory prohibitions this practice may be perfectly acceptable in the eyes and minds of the society. The purpose of this study is to evaluate prohibited and unlawful contracts of employments, how the law (both common law and statutory law) treats such contracts in the sense that; whether they are protected or not and to what extent these laws have been developed to influence modern attitudes concerning such contracts. One stark example is illustrated through case law where the court had to determine the validity of an employment contract concluded between an employer and an illegal immigrant.
- Full Text:
- Date Issued: 2009
The conservation and management of freshwater fishes in the Greater Addo Elephant National Park
- Authors: Traas, Graham Ronald Louis
- Date: 2009
- Subjects: Addo Elephant National Park (South Africa) , Freshwater fishes -- South Africa -- Eastern Cape , Fishery conservation -- South Africa -- Eastern Cape , Fishery management -- South Africa -- Eastern Cape , Estuarine fishes -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5247 , http://hdl.handle.net/10962/d1005090 , Addo Elephant National Park (South Africa) , Freshwater fishes -- South Africa -- Eastern Cape , Fishery conservation -- South Africa -- Eastern Cape , Fishery management -- South Africa -- Eastern Cape , Estuarine fishes -- South Africa -- Eastern Cape
- Description: Freshwater fish are the most imperilled vertebrate group with a high projected extinction rate. In general, the world's freshwater ichthyofauna is in a poor state and is threatened by habitat destruction, pollution, the effects of alien species, damming, water extraction and overfishing. Within South Africa, legislation supporting the conservation of aquatic habitats and its associated fauna is strong, but there is a lack of capacity and poor co-ordination between agencies responsible for the conservation and management. The Greater Addo Elephant National Park (GAENP) includes the upper catchments of five of the Sundays River tributaries. Since the optimal method of conserving freshwater aquatic biota is to conserve the headwaters of either the river or its tributaries, there is an opportunity to conserve the native ichthyofauna of the Sundays River system. The principal objective of this thesis was, therefore, to provide information pertinent to the conservation and management of the fishes in the Sundays River system. Sixteen species of freshwater and estuarine fish were sampled, of which eight were alien. Species composition in each of the rivers, with the exception of the Kabouga River, had changed significantly from previous studies. The distribution ranges of several indigenous species had reduced, while those of some alien species was increased. Two species not previously recorded, Labeo capensis and Gambusia affinis, were sampled. Alien species were sampled from all the tributaries. Diversity indices and community assemblage models were identified as approaches for monitoring the ichthyofauna in this species depauperate system. Diversity indices were not recommended for use as a monitoring tool, as they provided insufficient detail on community composition and structure. A modified depletion estimator was applied to multiple pass electrofishing data to determine the effects of various physico-chemical variables on the absolute abundance of Pseudobarbus afer, an endangered species. Pseudobarbus afer density was found to be positively correlated to the presence of boulders. Where P. afer were present, they were abundant. Of the total sampled catch, 21.8% was comprised of alien fishes. Clarias gariepinus was the most successful invader having penetrated all but one of the tributaries. Micropterus salmoides changed the species composition of the Wit River significantly through predation, and is potentially the most dangerous of the alien species in the Sundays River system, capable of extirpating a population of P. afer in as little as three days. Only one man-made barrier to the upstream migration of alien fishes was present on the tributaries, and several addition barriers are required to safeguard the populations of indigenous fish in the headwaters of these tributaries. Several management and conservation tools are presented and discussed, including river rehabilitation, translocation, eradication of alien species, erection of barrier weirs and captive breeding programmes. Public awareness and education is stressed because without support from the communities surrounding the GAENP, management plans for conservation of the indigenous ichthyofauna will, in all likelihood, fail.
- Full Text:
- Date Issued: 2009
- Authors: Traas, Graham Ronald Louis
- Date: 2009
- Subjects: Addo Elephant National Park (South Africa) , Freshwater fishes -- South Africa -- Eastern Cape , Fishery conservation -- South Africa -- Eastern Cape , Fishery management -- South Africa -- Eastern Cape , Estuarine fishes -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5247 , http://hdl.handle.net/10962/d1005090 , Addo Elephant National Park (South Africa) , Freshwater fishes -- South Africa -- Eastern Cape , Fishery conservation -- South Africa -- Eastern Cape , Fishery management -- South Africa -- Eastern Cape , Estuarine fishes -- South Africa -- Eastern Cape
- Description: Freshwater fish are the most imperilled vertebrate group with a high projected extinction rate. In general, the world's freshwater ichthyofauna is in a poor state and is threatened by habitat destruction, pollution, the effects of alien species, damming, water extraction and overfishing. Within South Africa, legislation supporting the conservation of aquatic habitats and its associated fauna is strong, but there is a lack of capacity and poor co-ordination between agencies responsible for the conservation and management. The Greater Addo Elephant National Park (GAENP) includes the upper catchments of five of the Sundays River tributaries. Since the optimal method of conserving freshwater aquatic biota is to conserve the headwaters of either the river or its tributaries, there is an opportunity to conserve the native ichthyofauna of the Sundays River system. The principal objective of this thesis was, therefore, to provide information pertinent to the conservation and management of the fishes in the Sundays River system. Sixteen species of freshwater and estuarine fish were sampled, of which eight were alien. Species composition in each of the rivers, with the exception of the Kabouga River, had changed significantly from previous studies. The distribution ranges of several indigenous species had reduced, while those of some alien species was increased. Two species not previously recorded, Labeo capensis and Gambusia affinis, were sampled. Alien species were sampled from all the tributaries. Diversity indices and community assemblage models were identified as approaches for monitoring the ichthyofauna in this species depauperate system. Diversity indices were not recommended for use as a monitoring tool, as they provided insufficient detail on community composition and structure. A modified depletion estimator was applied to multiple pass electrofishing data to determine the effects of various physico-chemical variables on the absolute abundance of Pseudobarbus afer, an endangered species. Pseudobarbus afer density was found to be positively correlated to the presence of boulders. Where P. afer were present, they were abundant. Of the total sampled catch, 21.8% was comprised of alien fishes. Clarias gariepinus was the most successful invader having penetrated all but one of the tributaries. Micropterus salmoides changed the species composition of the Wit River significantly through predation, and is potentially the most dangerous of the alien species in the Sundays River system, capable of extirpating a population of P. afer in as little as three days. Only one man-made barrier to the upstream migration of alien fishes was present on the tributaries, and several addition barriers are required to safeguard the populations of indigenous fish in the headwaters of these tributaries. Several management and conservation tools are presented and discussed, including river rehabilitation, translocation, eradication of alien species, erection of barrier weirs and captive breeding programmes. Public awareness and education is stressed because without support from the communities surrounding the GAENP, management plans for conservation of the indigenous ichthyofauna will, in all likelihood, fail.
- Full Text:
- Date Issued: 2009
The contribution of municipal commonage to local people's livelihoods in small South African towns
- Authors: Davenport, Nicholas Ashbury
- Date: 2009
- Subjects: Land tenure -- South Africa , Land reform -- South Africa , Property -- South Africa , Property rights -- South Africa , Commons -- South Africa -- Eastern Cape , Natural resources, Communal -- Management -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Households -- Economic aspects -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4749 , http://hdl.handle.net/10962/d1006976 , Land tenure -- South Africa , Land reform -- South Africa , Property -- South Africa , Property rights -- South Africa , Commons -- South Africa -- Eastern Cape , Natural resources, Communal -- Management -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Households -- Economic aspects -- South Africa -- Eastern Cape
- Description: To redress past discrepancies in land tenure, the ANC government acknowledged that land needs to be made accessible to the previously disadvantaged, announcing that commonage would be a pillar of their land reform programme. Municipal commonage is land granted by the state to municipalities for urban households to use. Presently many urbanites in South Africa seek a livelihood from commonage. However, there has been no livelihood valuation of the contribution commonage makes to previously disadvantaged households. Thus there is a need to calculate the benefits of the commonage programme. Through a two phase approach, this thesis investigated firstly, the proportion of township households which use commonage; and the main characteristics of those households. Secondly, the thesis looks at the extent to which commonage contributes to users' livelihoods and the dominant livelihood strategies pursued by user households. Data was collected for three towns in the Eastern Cape province of South Africa; Bathurst, Fort Beaufort, and Grahamstown. Firstly it was found that between 27-70% of households used commonage, with the largest town having the lowest proportion of users, and vice versa for the smallest town. In terms of household characteristics, each study town was unique. Both Bathurst and Grahamstown user households were poorer than non-using households, however all Fort Beaufort households were considered poor. To assess the benefits of the commonage programme, the marketed and non-marketed consumptive direct-use values of land-based livelihoods on commonage were calculated via the 'own reported values' method. Commonage contributions to total livelihoods ranged between 14-20%. If the contributors from commonage were excluded, over 10% of households in each study town would drop to living below the poverty line. Additionally, commonage was being used productively, with the productivity at each study town being worth over R1 000 per hectare and over R4.7 million per commonage. Finally, a typology of subsistence/survivalist commonage users is presented, with four types being identified. Overall, results suggest that commonage use has increased over the last decade. Moreover, due to food inflation and urbanisation the use of commonage is expected to increase further, highlighting the need for holistic commonage management plans to be created, which should include strategies such as sustainable grazing regimes and natural resource management.
- Full Text:
- Date Issued: 2009
- Authors: Davenport, Nicholas Ashbury
- Date: 2009
- Subjects: Land tenure -- South Africa , Land reform -- South Africa , Property -- South Africa , Property rights -- South Africa , Commons -- South Africa -- Eastern Cape , Natural resources, Communal -- Management -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Households -- Economic aspects -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4749 , http://hdl.handle.net/10962/d1006976 , Land tenure -- South Africa , Land reform -- South Africa , Property -- South Africa , Property rights -- South Africa , Commons -- South Africa -- Eastern Cape , Natural resources, Communal -- Management -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Households -- Economic aspects -- South Africa -- Eastern Cape
- Description: To redress past discrepancies in land tenure, the ANC government acknowledged that land needs to be made accessible to the previously disadvantaged, announcing that commonage would be a pillar of their land reform programme. Municipal commonage is land granted by the state to municipalities for urban households to use. Presently many urbanites in South Africa seek a livelihood from commonage. However, there has been no livelihood valuation of the contribution commonage makes to previously disadvantaged households. Thus there is a need to calculate the benefits of the commonage programme. Through a two phase approach, this thesis investigated firstly, the proportion of township households which use commonage; and the main characteristics of those households. Secondly, the thesis looks at the extent to which commonage contributes to users' livelihoods and the dominant livelihood strategies pursued by user households. Data was collected for three towns in the Eastern Cape province of South Africa; Bathurst, Fort Beaufort, and Grahamstown. Firstly it was found that between 27-70% of households used commonage, with the largest town having the lowest proportion of users, and vice versa for the smallest town. In terms of household characteristics, each study town was unique. Both Bathurst and Grahamstown user households were poorer than non-using households, however all Fort Beaufort households were considered poor. To assess the benefits of the commonage programme, the marketed and non-marketed consumptive direct-use values of land-based livelihoods on commonage were calculated via the 'own reported values' method. Commonage contributions to total livelihoods ranged between 14-20%. If the contributors from commonage were excluded, over 10% of households in each study town would drop to living below the poverty line. Additionally, commonage was being used productively, with the productivity at each study town being worth over R1 000 per hectare and over R4.7 million per commonage. Finally, a typology of subsistence/survivalist commonage users is presented, with four types being identified. Overall, results suggest that commonage use has increased over the last decade. Moreover, due to food inflation and urbanisation the use of commonage is expected to increase further, highlighting the need for holistic commonage management plans to be created, which should include strategies such as sustainable grazing regimes and natural resource management.
- Full Text:
- Date Issued: 2009
The coordination chemistry of Rhenium(V) with multidentate no-donor ligands
- Authors: Abrahams, Abubak'r
- Date: 2009
- Subjects: Rhenium , Ligands
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10370 , http://hdl.handle.net/10948/912 , Rhenium , Ligands
- Description: The neutral distorted octahedral complexes [ReOCl(L)] {H2L = N,N-bis(2- hydroxybenzyl)-2-(2-aminoethyl)dimethylamine (H2had), N,N-bis(2-hydroxybenzyl) aminomethylpyridine (H2hap); N,N-bis(2-hydroxybenzyl)-2-(2-aminoethyl)pyridine (H2hae)} were prepared by the reaction of trans-[ReOCl3(PPh3)2] with a twofold molar excess of H2L in ethanol. The X-ray structure determinations of [ReOCl(had)] and [ReOCl(hap)] were performed, and in both complexes the chloride is coordinated trans to the tripodal tertiary amino nitrogen, with a phenolate oxygen trans to the oxo oxygen. Treatment of trans-[ReO2(py)4]I with two equivalents and one equivalent each of H2had in acetone afforded the iodide salts of the oxypyridinium-ammonium zwitterions N1-(2-hydroxybenzyl)-N2,N2- dimethyl-N1-((2-oxypyridinium)-1-methyl)ethane-1,2-diamine [Hhpd]+ and N2,N2- dimethyl-N1-bis((2-oxypyridinium)-1-methyl)ethane-1,2-diamine [dod]+ respectively. In [Hhpd]I, one of the 2-hydroxyphenyl groups of H2had is substituted by an oxypyridinium group, and in [dod]I, both 2-hydroxyphenyl groups are converted. The X-ray crystal structure determination of the starting material H2had, [Hhpd]I and [dod]I reveals trigonal pyramidal geometries around the central amino nitrogen. The complex salt [ReO(bsa)]PF6 (H2bsa=bis(N-methylsalicylicylideneiminopropyl) amine) was prepared from the reaction of cis-[ReO2I(PPh3)2] with H2bsa in toluene. The dianionic pentadentate ligand bsa is coordinated to the ReO3+ moiety via one secondary amino and two imino nitrogens, and two anionic phenolate oxygens. The complex was characterized by spectroscopy and analytical data, and the structure has been determined by single-crystal X-ray diffraction analysis. The complex exhibits a distorted octahedral geometry around the central rhenium(V) ion, with the basal plane being defined by a phenolate oxygen, two imino nitrogens and the secondary amino. ix A. Abrahams Nelson Mandela Metropolitan University The reaction of a two-fold molar excess of the potentially NN-donor ligand 2,2’- dipyridylamine (dpa) with trans-[ReO(OEt)Cl2(PPh3)2] in ethanol led to the isolation of [ReOCl2(OEt)(dpa)]. The X-ray crystal structure shows that the NN-chelated dpa is coordinated in the equatorial plane cis to the oxo and ethoxo groups, which are in trans positions relative to each other. The treatment of trans- [ReOCl3(PPh3)2] with a tenfold molar excess of dpa in ethanol at the refluxing temperature yielded the trans-dioxo complex [ReO2(dpa)2]Cl, but with a twofold molar excess only (μ-O)[{ReOCl2(dpa)}2] was isolated. Repeating the latter reaction with (n-Bu4N)[ReOCl4] as starting material in ethanol at room temperature a dark green product, also with the formulation (μ-O)[{ReOCl2(dpa)}2], was isolated. The reaction of equimolar quantities of bis(pyridin-2-yl)methyl)amine (HBPA) with (n-Bu4N)[ReOCl4] in acetone at room temperature led to the isolation of the sixcoordinate rhenium(V) complex [ReOCl(H2O)(BPA)]Cl. IR, NMR and X-ray crystallographic results indicate that BPA is coordinated as a tridentate uninegative chelate, with deprotonation of the amine nitrogen. The water molecule is coordinated trans to the oxo group, with the Re=O and Re-OH2 bond distances equal to 1.663(9) and 2.21(1) Å respectively. Complexes of the general formula [ReOX2{(C5H4N)CH(O)CH2(C5H4N)}] (X = Cl, I) were prepared by the reactions of trans-[ReOCl3(PPh3)2] and trans- [ReOI2(OEt)(PPh3)2] with cis-1,2-di-(2-pyridyl)ethylene (DPE) in ethanol and benzene in air. Experimental evidence shows that the coordinated DPE ligand has undergone addition of water at the ethylenic carbons, and that the (C5H4N)CH(O)CH2(C5H4N) moiety acts as a uninegative tridentate NON-donor ligand. The X-ray crystal structures of both complexes show a distorted octahedral geometry around the rhenium(V) centre. The treatment of trans-[ReOCl3(PPh3)2] with H2dbd in a 2:1 molar ratio in acetonitrile led to the isolation of the ligand-bridged dimer (μ-dbd)[ReOCl2(PPh3)]2. The X-ray crystal structure of the complex reveals a dinuclear structure in which two rhenium(V) ions are bridged by the dbd ligand. Each rhenium ion is in a x A. Abrahams Nelson Mandela Metropolitan University distorted octahedral geometry. The basal plane is defined by a phosphorus atom of the PPh3 group, two chlorides cis to each other, and a pyridyl nitrogen atom of dbd. The oxo group and alcoholate oxygen of dbd lie in trans axial positions. The complexes cis-[ReOX2(msa)(PPh3)] (X = Cl, Br, I) were prepared from trans- [ReOCl3(PPh3)2], trans-[ReOBr3(PPh3)2] or trans-[ReOI2(OEt)(PPh3)2] with 2-(1- iminoethyl)phenol (Hmsa) in acetonitrile. An X-ray crystallographic study shows that the bonding distances and angles in the comlexes are nearly identical, and that the two halides in each complex are coordinated cis to each other in the equatorial plane cis to the oxo group. The oxo-bridged dinuclear rhenium(V) complex [(μ-O){ReOCl(amp)}2] was prepared by the reaction of trans-[ReOCl3(PPh3)2] and 6-amino-3-methyl-1-phenyl- 4-azahept-2-ene-1-one (Hamp) in acetone. The characterization of the complex by elemental analysis, infrared and 1H NMR spectroscopy and X-ray crystallography shows that amp is coordinated as a monoanionic NNO-donor chelate as an amino-amido ketone. However, the reaction of the similar ligand 7- amino-4,7-dimethyl-5-aza-3-octen-2-one (Hada) with [Re(CO)5Br] produced the product fac-[Re(CO)3Br(Hada)], with Hada coordinated as a neutral NN-donor amino-imino-ketone.
- Full Text:
- Date Issued: 2009
- Authors: Abrahams, Abubak'r
- Date: 2009
- Subjects: Rhenium , Ligands
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10370 , http://hdl.handle.net/10948/912 , Rhenium , Ligands
- Description: The neutral distorted octahedral complexes [ReOCl(L)] {H2L = N,N-bis(2- hydroxybenzyl)-2-(2-aminoethyl)dimethylamine (H2had), N,N-bis(2-hydroxybenzyl) aminomethylpyridine (H2hap); N,N-bis(2-hydroxybenzyl)-2-(2-aminoethyl)pyridine (H2hae)} were prepared by the reaction of trans-[ReOCl3(PPh3)2] with a twofold molar excess of H2L in ethanol. The X-ray structure determinations of [ReOCl(had)] and [ReOCl(hap)] were performed, and in both complexes the chloride is coordinated trans to the tripodal tertiary amino nitrogen, with a phenolate oxygen trans to the oxo oxygen. Treatment of trans-[ReO2(py)4]I with two equivalents and one equivalent each of H2had in acetone afforded the iodide salts of the oxypyridinium-ammonium zwitterions N1-(2-hydroxybenzyl)-N2,N2- dimethyl-N1-((2-oxypyridinium)-1-methyl)ethane-1,2-diamine [Hhpd]+ and N2,N2- dimethyl-N1-bis((2-oxypyridinium)-1-methyl)ethane-1,2-diamine [dod]+ respectively. In [Hhpd]I, one of the 2-hydroxyphenyl groups of H2had is substituted by an oxypyridinium group, and in [dod]I, both 2-hydroxyphenyl groups are converted. The X-ray crystal structure determination of the starting material H2had, [Hhpd]I and [dod]I reveals trigonal pyramidal geometries around the central amino nitrogen. The complex salt [ReO(bsa)]PF6 (H2bsa=bis(N-methylsalicylicylideneiminopropyl) amine) was prepared from the reaction of cis-[ReO2I(PPh3)2] with H2bsa in toluene. The dianionic pentadentate ligand bsa is coordinated to the ReO3+ moiety via one secondary amino and two imino nitrogens, and two anionic phenolate oxygens. The complex was characterized by spectroscopy and analytical data, and the structure has been determined by single-crystal X-ray diffraction analysis. The complex exhibits a distorted octahedral geometry around the central rhenium(V) ion, with the basal plane being defined by a phenolate oxygen, two imino nitrogens and the secondary amino. ix A. Abrahams Nelson Mandela Metropolitan University The reaction of a two-fold molar excess of the potentially NN-donor ligand 2,2’- dipyridylamine (dpa) with trans-[ReO(OEt)Cl2(PPh3)2] in ethanol led to the isolation of [ReOCl2(OEt)(dpa)]. The X-ray crystal structure shows that the NN-chelated dpa is coordinated in the equatorial plane cis to the oxo and ethoxo groups, which are in trans positions relative to each other. The treatment of trans- [ReOCl3(PPh3)2] with a tenfold molar excess of dpa in ethanol at the refluxing temperature yielded the trans-dioxo complex [ReO2(dpa)2]Cl, but with a twofold molar excess only (μ-O)[{ReOCl2(dpa)}2] was isolated. Repeating the latter reaction with (n-Bu4N)[ReOCl4] as starting material in ethanol at room temperature a dark green product, also with the formulation (μ-O)[{ReOCl2(dpa)}2], was isolated. The reaction of equimolar quantities of bis(pyridin-2-yl)methyl)amine (HBPA) with (n-Bu4N)[ReOCl4] in acetone at room temperature led to the isolation of the sixcoordinate rhenium(V) complex [ReOCl(H2O)(BPA)]Cl. IR, NMR and X-ray crystallographic results indicate that BPA is coordinated as a tridentate uninegative chelate, with deprotonation of the amine nitrogen. The water molecule is coordinated trans to the oxo group, with the Re=O and Re-OH2 bond distances equal to 1.663(9) and 2.21(1) Å respectively. Complexes of the general formula [ReOX2{(C5H4N)CH(O)CH2(C5H4N)}] (X = Cl, I) were prepared by the reactions of trans-[ReOCl3(PPh3)2] and trans- [ReOI2(OEt)(PPh3)2] with cis-1,2-di-(2-pyridyl)ethylene (DPE) in ethanol and benzene in air. Experimental evidence shows that the coordinated DPE ligand has undergone addition of water at the ethylenic carbons, and that the (C5H4N)CH(O)CH2(C5H4N) moiety acts as a uninegative tridentate NON-donor ligand. The X-ray crystal structures of both complexes show a distorted octahedral geometry around the rhenium(V) centre. The treatment of trans-[ReOCl3(PPh3)2] with H2dbd in a 2:1 molar ratio in acetonitrile led to the isolation of the ligand-bridged dimer (μ-dbd)[ReOCl2(PPh3)]2. The X-ray crystal structure of the complex reveals a dinuclear structure in which two rhenium(V) ions are bridged by the dbd ligand. Each rhenium ion is in a x A. Abrahams Nelson Mandela Metropolitan University distorted octahedral geometry. The basal plane is defined by a phosphorus atom of the PPh3 group, two chlorides cis to each other, and a pyridyl nitrogen atom of dbd. The oxo group and alcoholate oxygen of dbd lie in trans axial positions. The complexes cis-[ReOX2(msa)(PPh3)] (X = Cl, Br, I) were prepared from trans- [ReOCl3(PPh3)2], trans-[ReOBr3(PPh3)2] or trans-[ReOI2(OEt)(PPh3)2] with 2-(1- iminoethyl)phenol (Hmsa) in acetonitrile. An X-ray crystallographic study shows that the bonding distances and angles in the comlexes are nearly identical, and that the two halides in each complex are coordinated cis to each other in the equatorial plane cis to the oxo group. The oxo-bridged dinuclear rhenium(V) complex [(μ-O){ReOCl(amp)}2] was prepared by the reaction of trans-[ReOCl3(PPh3)2] and 6-amino-3-methyl-1-phenyl- 4-azahept-2-ene-1-one (Hamp) in acetone. The characterization of the complex by elemental analysis, infrared and 1H NMR spectroscopy and X-ray crystallography shows that amp is coordinated as a monoanionic NNO-donor chelate as an amino-amido ketone. However, the reaction of the similar ligand 7- amino-4,7-dimethyl-5-aza-3-octen-2-one (Hada) with [Re(CO)5Br] produced the product fac-[Re(CO)3Br(Hada)], with Hada coordinated as a neutral NN-donor amino-imino-ketone.
- Full Text:
- Date Issued: 2009
The covariation of South African and foreign equity returns during bull and bear runs : implications for portfolio diversification
- Authors: Mhlanga, Godfrey
- Date: 2009
- Subjects: Stock exchanges -- South Africa , Portfolio management -- South Africa , Investments -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:944 , http://hdl.handle.net/10962/d1002678
- Description: This study examines the pattern of covariation of the industrial index returns of South Africa and foreign industrial sectors. This follows recent increase in national equity correlations and increases in the influence of industry effects in portfolio diversification. The covariation pattern in returns across industries and countries during both bull and bear runs is examined using correlation analysis to determine if there is a difference between the two epochs. The study presents preliminary evidence of the covariation between sectors during a bear and a bull run. Return covariation among sectors is impelled to a greater extent by country-specific factors than by industry-specific factors, implying the segmentation of industrial sectors. Thus, South African investors can in general gain more if a portfolio comprising shares across industries and countries is held, even if these investors buy shares from similar industries.
- Full Text:
- Date Issued: 2009
- Authors: Mhlanga, Godfrey
- Date: 2009
- Subjects: Stock exchanges -- South Africa , Portfolio management -- South Africa , Investments -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:944 , http://hdl.handle.net/10962/d1002678
- Description: This study examines the pattern of covariation of the industrial index returns of South Africa and foreign industrial sectors. This follows recent increase in national equity correlations and increases in the influence of industry effects in portfolio diversification. The covariation pattern in returns across industries and countries during both bull and bear runs is examined using correlation analysis to determine if there is a difference between the two epochs. The study presents preliminary evidence of the covariation between sectors during a bear and a bull run. Return covariation among sectors is impelled to a greater extent by country-specific factors than by industry-specific factors, implying the segmentation of industrial sectors. Thus, South African investors can in general gain more if a portfolio comprising shares across industries and countries is held, even if these investors buy shares from similar industries.
- Full Text:
- Date Issued: 2009
The cultural determinants of success in Indian owned family businesses
- Authors: Adams, Leigh Christie
- Date: 2009
- Subjects: Family-owned business enterprises -- Management , Indian business enterprises , Small business -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8543 , http://hdl.handle.net/10948/1258 , Family-owned business enterprises -- Management , Indian business enterprises , Small business -- Management
- Description: Family owned businesses play a vital role in the economy of a country, therefore their sustainability and succession is a topic that requires adequate research and analysis. This is required to determine the impact and contribution at a socioeconomic level and future development of the family owned business. Within the Nelson Mandela Metropolitan area previous research has been conducted analysing the above with regard to Greek family businesses. There is a little evidence to suggest similar studies have been conducted on Indian owned family businesses, specifically businesses operating at a third generation level. This research will therefore analyse Indian owned family businesses that are at a minimum level of third generation within the Nelson Mandela Metropolitan area. The purpose is to investigate whether there is any specific cultural attributes of the Indian culture which have contributed to their success.
- Full Text:
- Date Issued: 2009
- Authors: Adams, Leigh Christie
- Date: 2009
- Subjects: Family-owned business enterprises -- Management , Indian business enterprises , Small business -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8543 , http://hdl.handle.net/10948/1258 , Family-owned business enterprises -- Management , Indian business enterprises , Small business -- Management
- Description: Family owned businesses play a vital role in the economy of a country, therefore their sustainability and succession is a topic that requires adequate research and analysis. This is required to determine the impact and contribution at a socioeconomic level and future development of the family owned business. Within the Nelson Mandela Metropolitan area previous research has been conducted analysing the above with regard to Greek family businesses. There is a little evidence to suggest similar studies have been conducted on Indian owned family businesses, specifically businesses operating at a third generation level. This research will therefore analyse Indian owned family businesses that are at a minimum level of third generation within the Nelson Mandela Metropolitan area. The purpose is to investigate whether there is any specific cultural attributes of the Indian culture which have contributed to their success.
- Full Text:
- Date Issued: 2009
The current state of Black female empowerment in the construction industry measured against broad-based Black economic empowerment scorecard
- Authors: Podges, Joan Winnifred
- Date: 2009
- Subjects: Women -- Employment -- South Africa , Women executives -- South Africa , Business enterprises, Black -- South Africa , Women, Black -- South Africa , Sex discrimination in employment -- South Africa , Women-owned business enterprises -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8675 , http://hdl.handle.net/10948/1161 , Women -- Employment -- South Africa , Women executives -- South Africa , Business enterprises, Black -- South Africa , Women, Black -- South Africa , Sex discrimination in employment -- South Africa , Women-owned business enterprises -- South Africa
- Description: The Government of South Africa has placed a lot of emphasis on economic growth and the involvement of Black people in the mainstream of the economy. The implementation of Broad-Based Black Economic Empowerment (B-BBEE) created opportunities for direct empowerment of Black females in ownership and management. The Construction Industry is being challenged to increase the number of Black females in management and ownership levels. Due to the nature of the Industry, only a small population of females considers Construction as a career option. The Industry has also lost a significant number of skilled Engineers and is experiencing a shortage of skilled managers in Middle and Senior Management Levels. The research problem questioned the current state of empowerment for Black women in the Construction Industry as measured against the B-BBEE Scorecard. The literature review focused on the requirements of the B-BBEE scorecard and Construction Charter. The second phase focused on gender equality and the achievements of women in Construction. The research design was done by using questionnaires to the South African Federation of Civil Engineering Contractors (Safcec) members in the Eastern Cape. The research design and survey aimed to determine the status of empowerment in the Construction Industry. With reference to both the literature review and the empirical findings the state of female empowerment can be determined. Therefore iv recommendations and opportunities for further research in this regard can be identified.
- Full Text:
- Date Issued: 2009
- Authors: Podges, Joan Winnifred
- Date: 2009
- Subjects: Women -- Employment -- South Africa , Women executives -- South Africa , Business enterprises, Black -- South Africa , Women, Black -- South Africa , Sex discrimination in employment -- South Africa , Women-owned business enterprises -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8675 , http://hdl.handle.net/10948/1161 , Women -- Employment -- South Africa , Women executives -- South Africa , Business enterprises, Black -- South Africa , Women, Black -- South Africa , Sex discrimination in employment -- South Africa , Women-owned business enterprises -- South Africa
- Description: The Government of South Africa has placed a lot of emphasis on economic growth and the involvement of Black people in the mainstream of the economy. The implementation of Broad-Based Black Economic Empowerment (B-BBEE) created opportunities for direct empowerment of Black females in ownership and management. The Construction Industry is being challenged to increase the number of Black females in management and ownership levels. Due to the nature of the Industry, only a small population of females considers Construction as a career option. The Industry has also lost a significant number of skilled Engineers and is experiencing a shortage of skilled managers in Middle and Senior Management Levels. The research problem questioned the current state of empowerment for Black women in the Construction Industry as measured against the B-BBEE Scorecard. The literature review focused on the requirements of the B-BBEE scorecard and Construction Charter. The second phase focused on gender equality and the achievements of women in Construction. The research design was done by using questionnaires to the South African Federation of Civil Engineering Contractors (Safcec) members in the Eastern Cape. The research design and survey aimed to determine the status of empowerment in the Construction Industry. With reference to both the literature review and the empirical findings the state of female empowerment can be determined. Therefore iv recommendations and opportunities for further research in this regard can be identified.
- Full Text:
- Date Issued: 2009
The Darfur conflict from the perspective of the rebel justice and equality movement
- Authors: Heleta, Savo
- Date: 2009
- Subjects: Peace-building -- Sudan -- Darfur , Genocide -- Sudan -- Darfur , Sudan -- History -- Darfur Conflict, 2003-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8222 , http://hdl.handle.net/10948/970 , Peace-building -- Sudan -- Darfur , Genocide -- Sudan -- Darfur , Sudan -- History -- Darfur Conflict, 2003-
- Description: In 2003, a conflict broke out in Darfur, Sudan’s western province, between the mainly “African” rebels and the government forces and their proxy “Arab” militias. It is estimated that about 200,000 people have so far died in the conflict from fighting, disease, and starvation. The UN and aid agencies estimate that over two million Darfurians, out of the population of about six million, are living in refugee camps. Even though the majority of all deaths in Darfur have occurred in 2003 and 2004, the conflict is nowhere near the end. Even after more than five years since the Darfur conflict began, there is hardly any comprehensive information about the rebels’ aims, objectives, and plans for the future. We cannot fully understand the conflict and plan peace negotiations between the warring parties if we do not know enough about the rebels. This study has critically explored the aims and perspectives of the Justice and Equality Movement, currently the most powerful Darfur rebel movement. The author has used the first-hand information gathered through interviews with the representatives of the rebel movement and additional data about the conflict and the rebels collected through an extensive literature analysis to portray the movement and its aims, perspectives, and plans for the future. Using the grounded theory approach as the data analysis tool, the author has presented key findings about the Darfur conflict from the perspective of the Justice and Equality Movement that have emerged from the data collected in this study.
- Full Text:
- Date Issued: 2009
- Authors: Heleta, Savo
- Date: 2009
- Subjects: Peace-building -- Sudan -- Darfur , Genocide -- Sudan -- Darfur , Sudan -- History -- Darfur Conflict, 2003-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8222 , http://hdl.handle.net/10948/970 , Peace-building -- Sudan -- Darfur , Genocide -- Sudan -- Darfur , Sudan -- History -- Darfur Conflict, 2003-
- Description: In 2003, a conflict broke out in Darfur, Sudan’s western province, between the mainly “African” rebels and the government forces and their proxy “Arab” militias. It is estimated that about 200,000 people have so far died in the conflict from fighting, disease, and starvation. The UN and aid agencies estimate that over two million Darfurians, out of the population of about six million, are living in refugee camps. Even though the majority of all deaths in Darfur have occurred in 2003 and 2004, the conflict is nowhere near the end. Even after more than five years since the Darfur conflict began, there is hardly any comprehensive information about the rebels’ aims, objectives, and plans for the future. We cannot fully understand the conflict and plan peace negotiations between the warring parties if we do not know enough about the rebels. This study has critically explored the aims and perspectives of the Justice and Equality Movement, currently the most powerful Darfur rebel movement. The author has used the first-hand information gathered through interviews with the representatives of the rebel movement and additional data about the conflict and the rebels collected through an extensive literature analysis to portray the movement and its aims, perspectives, and plans for the future. Using the grounded theory approach as the data analysis tool, the author has presented key findings about the Darfur conflict from the perspective of the Justice and Equality Movement that have emerged from the data collected in this study.
- Full Text:
- Date Issued: 2009
The design and synthesis of novel HIV-1 protease inhibitors
- Authors: Tukulula, Matshawandile
- Date: 2009
- Subjects: Protease Inhibitors HIV infections -- Treatment AIDS (Disease) -- Treatment HIV (Viruses) Indolizine -- Derivatives Heterocyclic compounds -- Derivatives Nuclear magnetic resonance Quinoline
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4305 , http://hdl.handle.net/10962/d1004963
- Description: This study has focused on the synthesis of truncated analogues of the hydroxyethylene dipeptide isosteres, such as Ritonavir®, currently in clinical use as HIV-1 protease inhibitors. The reactions of pyridine-2- and quinoline-2-carbaldehydes with methyl acrylate, in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) or 3- hydroxyquinuclidine (3-HQ) as nucleophilic catalysts, have afforded a series of Baylis- Hillman adducts, acetylation and cyclisation of which have provided access to a series of indolizine-2-carboxylate esters. The carboxylic acids, obtained by base-catalyzed hydrolysis of these esters, have been coupled with various protected (and unprotected) amino compounds using the peptide coupling agent, 1,1’-carbonyldiimidazole (CDI), to afford a series of indolizine-2-carboxamides as indolizine-based truncated Ritonavir® analogues in quantitative yield. Aza-Michael reactions of pyridine-3-carbaldehydederived Baylis-Hillman adducts with various amino compounds have provided access to a range of pyridine-based products as mixtures of diastereomeric aza-Michael products. The assignment of the relative stereochemistry of the aza-Michael products has been established using 1-D and 2-NOESY experiments and computer modelling techniques. Computer modelling studies have also been conducted on selected aza-Michael products using ACCELRYS Cerius2 software, followed by interactive docking into the HIV-1 protease receptor site, using AUTODOCK 4.0. The docking studies have revealed hydrogen-bonding interactions between the enzyme and the synthetic ligands. Saturation Transfer Difference (STD) NMR experiments have also indicated binding of some of the aza-Michael products to the HIV-1 protease subtype C enzyme, thus indicating their binding and possible inhibitory potential.
- Full Text:
- Date Issued: 2009
- Authors: Tukulula, Matshawandile
- Date: 2009
- Subjects: Protease Inhibitors HIV infections -- Treatment AIDS (Disease) -- Treatment HIV (Viruses) Indolizine -- Derivatives Heterocyclic compounds -- Derivatives Nuclear magnetic resonance Quinoline
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4305 , http://hdl.handle.net/10962/d1004963
- Description: This study has focused on the synthesis of truncated analogues of the hydroxyethylene dipeptide isosteres, such as Ritonavir®, currently in clinical use as HIV-1 protease inhibitors. The reactions of pyridine-2- and quinoline-2-carbaldehydes with methyl acrylate, in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) or 3- hydroxyquinuclidine (3-HQ) as nucleophilic catalysts, have afforded a series of Baylis- Hillman adducts, acetylation and cyclisation of which have provided access to a series of indolizine-2-carboxylate esters. The carboxylic acids, obtained by base-catalyzed hydrolysis of these esters, have been coupled with various protected (and unprotected) amino compounds using the peptide coupling agent, 1,1’-carbonyldiimidazole (CDI), to afford a series of indolizine-2-carboxamides as indolizine-based truncated Ritonavir® analogues in quantitative yield. Aza-Michael reactions of pyridine-3-carbaldehydederived Baylis-Hillman adducts with various amino compounds have provided access to a range of pyridine-based products as mixtures of diastereomeric aza-Michael products. The assignment of the relative stereochemistry of the aza-Michael products has been established using 1-D and 2-NOESY experiments and computer modelling techniques. Computer modelling studies have also been conducted on selected aza-Michael products using ACCELRYS Cerius2 software, followed by interactive docking into the HIV-1 protease receptor site, using AUTODOCK 4.0. The docking studies have revealed hydrogen-bonding interactions between the enzyme and the synthetic ligands. Saturation Transfer Difference (STD) NMR experiments have also indicated binding of some of the aza-Michael products to the HIV-1 protease subtype C enzyme, thus indicating their binding and possible inhibitory potential.
- Full Text:
- Date Issued: 2009
The development and evaluation of a programme to promote sensitive pscyhotherapeutic practice with gay men and lesbians
- Authors: Coetzee, Catherine Ann
- Date: 2009
- Subjects: Psychotherapy -- Practice -- South Africa Psychoanalysis and homosexuality -- South Africa Homosexuality -- Social aspects -- South Africa Homosexuality -- Psychological aspects -- South Africa Psychotherapy -- Moral and ethical aspects -- South Africa Psychologists -- Training of -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2952 , http://hdl.handle.net/10962/d1002461
- Description: Clinical psychology’s relevance and future viability depend on its ability to render services that are relevant and sensitive to multicultural and minority issues. Lesbian, gay, bisexual and transgendered people are one such group that professional psychology – both in South Africa and abroad - has identified as having unique treatment needs for which psychologists require specialised knowledge and skills in order to render appropriate treatment. Competence to treat non-heterosexual patients has been framed in terms of a gay affirmative paradigm which has as its basic tenet the recognition that same-gender orientation is not pathological but rather a healthy alternative to heterosexuality. From this perspective being “gay friendly” or “gay accepting” is not enough. To implement a gay affirmative approach in practice, practitioners must have resolved their possible prejudice and heterosexist bias and have the requisite knowledge of concerns unique to lesbian, gay, and bisexual (LGB) individuals to be able to apply their skills in a culturally sensitive manner. Although more American post-graduate psychology programmes are addressing sexual diversity, their failure to produce psychologists who feel competent to treat lesbian/gay or bisexual individuals has highlighted the need to develop effective training strategies based on empirical nvestigation. The dearth of comparable data about local South African psychology training prompted this inquiry which had four broad aims namely, (i) to establish to what extent trainees’ prior training had equipped them with the knowledge, awareness, and skills to approach their work with non-heterosexual patients in a gay affirmative manner, and (ii) to implement and (iii) to evaluate to what extent a brief structured training programme is effective in engaging the trainees; in increasing knowledge, in raising awareness, and in changing specific attitudes and imparting specific skills required for treating lesbian and gay patients.; and (iv) what, if any, recommendations should be made for the future with respect to training of sychologists in this area? The field of sexual orientation research has been expanded to include issues pertaining to bisexual, transgendered and intersexed people, but serious time constraints meant that issues pertaining to these groups could not be addressed in depth. Although the exclusion of these groups is problematic and may be seen as reinforcing their invisibility, it was decided to focus primarily on gay and lesbian issues s an introduction to same-sex orientation. It is envisaged that bisexual and transgender issues would be dealt with in depth in more advanced training. Nine trainee psychologists employed at hospitals in the greater Cape Town area volunteered to participate in the programme which comprised a series of two-hour experiential workshops offered once a week over six weeks. The study employed both quantitative and qualitative data analysis methods. The first stage entailed gathering information to better understand trainees’ existing level of competence. Individual interviews were conducted prior to the course to obtain data about their attitudes and perceptions regarding the need for such specialised training, and how qualified they considered themselves to be to treat LGB patients, and their experience in this regard. For the purpose of the over-all analysis information was also gathered about pertinent personal and social characteristics of the trainees, as well as their contact with lesbian/gay persons. In addition, an attitude survey and the Lesbian, Gay, and Bisexual Counselling Self-efficacy Scale (LGB-CSI) were administered to obtain benchmarks against which change could be measured. The second stage involved the implementation of the educational programme and gathering information about trainees’ responses to its various components. This stage concentrated on discovering how individual trainees reacted to material on lesbian, gay, and bisexual issues and how they used the programme to improve their self-awareness and skills. The results indicate that local psychology training might not address same-gender orientation adequately, thus reinforcing trainees’ belief that sexual orientation is irrelevant, and that their generalist training equips them to work with gay/lesbian/bisexual patients. While the training strengthened existing positive attitudes, it was less effective in changing blatant antigay prejudice. However, both quantitative and qualitative data suggest that the programme increased individuals’ awareness and insight into their previously unrecognised heterosexist biases and created greater understanding of the effects of stigmatisation on sexual minority individuals. In addition, the training increased trainee’s sense of competence to provide affirmative treatment as evidenced by the significant differences between the pre- and post-training mean scores on the Relationship, Knowledge, and Advocacy Scales and between the mid- and post-training means scores on the Assessment and Awareness Scales of the LGB-CSI. Despite the limited generalisability of these findings on account of possible sampling bias, the need and value of such training was confirmed by trainees’ recommendation that this programme should be a mandatory offering in the first year of clinical psychology training.
- Full Text:
- Date Issued: 2009
- Authors: Coetzee, Catherine Ann
- Date: 2009
- Subjects: Psychotherapy -- Practice -- South Africa Psychoanalysis and homosexuality -- South Africa Homosexuality -- Social aspects -- South Africa Homosexuality -- Psychological aspects -- South Africa Psychotherapy -- Moral and ethical aspects -- South Africa Psychologists -- Training of -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2952 , http://hdl.handle.net/10962/d1002461
- Description: Clinical psychology’s relevance and future viability depend on its ability to render services that are relevant and sensitive to multicultural and minority issues. Lesbian, gay, bisexual and transgendered people are one such group that professional psychology – both in South Africa and abroad - has identified as having unique treatment needs for which psychologists require specialised knowledge and skills in order to render appropriate treatment. Competence to treat non-heterosexual patients has been framed in terms of a gay affirmative paradigm which has as its basic tenet the recognition that same-gender orientation is not pathological but rather a healthy alternative to heterosexuality. From this perspective being “gay friendly” or “gay accepting” is not enough. To implement a gay affirmative approach in practice, practitioners must have resolved their possible prejudice and heterosexist bias and have the requisite knowledge of concerns unique to lesbian, gay, and bisexual (LGB) individuals to be able to apply their skills in a culturally sensitive manner. Although more American post-graduate psychology programmes are addressing sexual diversity, their failure to produce psychologists who feel competent to treat lesbian/gay or bisexual individuals has highlighted the need to develop effective training strategies based on empirical nvestigation. The dearth of comparable data about local South African psychology training prompted this inquiry which had four broad aims namely, (i) to establish to what extent trainees’ prior training had equipped them with the knowledge, awareness, and skills to approach their work with non-heterosexual patients in a gay affirmative manner, and (ii) to implement and (iii) to evaluate to what extent a brief structured training programme is effective in engaging the trainees; in increasing knowledge, in raising awareness, and in changing specific attitudes and imparting specific skills required for treating lesbian and gay patients.; and (iv) what, if any, recommendations should be made for the future with respect to training of sychologists in this area? The field of sexual orientation research has been expanded to include issues pertaining to bisexual, transgendered and intersexed people, but serious time constraints meant that issues pertaining to these groups could not be addressed in depth. Although the exclusion of these groups is problematic and may be seen as reinforcing their invisibility, it was decided to focus primarily on gay and lesbian issues s an introduction to same-sex orientation. It is envisaged that bisexual and transgender issues would be dealt with in depth in more advanced training. Nine trainee psychologists employed at hospitals in the greater Cape Town area volunteered to participate in the programme which comprised a series of two-hour experiential workshops offered once a week over six weeks. The study employed both quantitative and qualitative data analysis methods. The first stage entailed gathering information to better understand trainees’ existing level of competence. Individual interviews were conducted prior to the course to obtain data about their attitudes and perceptions regarding the need for such specialised training, and how qualified they considered themselves to be to treat LGB patients, and their experience in this regard. For the purpose of the over-all analysis information was also gathered about pertinent personal and social characteristics of the trainees, as well as their contact with lesbian/gay persons. In addition, an attitude survey and the Lesbian, Gay, and Bisexual Counselling Self-efficacy Scale (LGB-CSI) were administered to obtain benchmarks against which change could be measured. The second stage involved the implementation of the educational programme and gathering information about trainees’ responses to its various components. This stage concentrated on discovering how individual trainees reacted to material on lesbian, gay, and bisexual issues and how they used the programme to improve their self-awareness and skills. The results indicate that local psychology training might not address same-gender orientation adequately, thus reinforcing trainees’ belief that sexual orientation is irrelevant, and that their generalist training equips them to work with gay/lesbian/bisexual patients. While the training strengthened existing positive attitudes, it was less effective in changing blatant antigay prejudice. However, both quantitative and qualitative data suggest that the programme increased individuals’ awareness and insight into their previously unrecognised heterosexist biases and created greater understanding of the effects of stigmatisation on sexual minority individuals. In addition, the training increased trainee’s sense of competence to provide affirmative treatment as evidenced by the significant differences between the pre- and post-training mean scores on the Relationship, Knowledge, and Advocacy Scales and between the mid- and post-training means scores on the Assessment and Awareness Scales of the LGB-CSI. Despite the limited generalisability of these findings on account of possible sampling bias, the need and value of such training was confirmed by trainees’ recommendation that this programme should be a mandatory offering in the first year of clinical psychology training.
- Full Text:
- Date Issued: 2009
The development and evaluation of gaze selection techniques
- Authors: Van Tonder, Martin Stephen
- Date: 2009
- Subjects: Human-computer interaction , User interfaces (Computer systems) , Gaze
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10469 , http://hdl.handle.net/10948/882 , Human-computer interaction , User interfaces (Computer systems) , Gaze
- Description: Eye gaze interaction enables users to interact with computers using their eyes. A wide variety of eye gaze interaction techniques have been developed to support this type of interaction. Gaze selection techniques, a class of eye gaze interaction techniques which support target selection, are the subject of this research. Researchers developing these techniques face a number of challenges. The most significant challenge is the limited accuracy of eye tracking equipment (due to the properties of the human eye). The design of gaze selection techniques is dominated by this constraint. Despite decades of research, existing techniques are still significantly less accurate than the mouse. A recently developed technique, EyePoint, represents the state of the art in gaze selection techniques. EyePoint combines gaze input with keyboard input. Evaluation results for this technique are encouraging, but accuracy is still a concern. Early trigger errors, resulting from users triggering a selection before looking at the intended target, were found to be the most commonly occurring errors for this technique. The primary goal of this research was to improve the usability of gaze selection techniques. In order to achieve this goal, novel gaze selection techniques were developed. New techniques were developed by combining elements of existing techniques in novel ways. Seven novel gaze selection techniques were developed. Three of these techniques were selected for evaluation. A software framework was developed for implementing and evaluating gaze selection techniques. This framework was used to implement the gaze selection techniques developed during this research. Implementing and evaluating all of the techniques using a common framework ensured consistency when comparing the techniques. The novel techniques which were developed were evaluated against EyePoint and the mouse using the framework. The three novel techniques evaluated were named TargetPoint, StaggerPoint and ScanPoint. TargetPoint combines motor space expansion with a visual feedback highlight whereas the StaggerPoint and TargetPoint designs explore novel approaches to target selection disambiguation. A usability evaluation of the three novel techniques alongside EyePoint and the mouse revealed some interesting trends. TargetPoint was found to be more usable and accurate than EyePoint. This novel technique also proved more popular with test participants. One aspect of TargetPoint which proved particularly popular was the visual feedback highlight, a feature which was found to be a more effective method of combating early trigger errors than existing approaches. StaggerPoint was more efficient than EyePoint, but was less effective and satisfying. ScanPoint was the least popular technique. The benefits of providing a visual feedback highlight and test participants' positive views thereof contradict views expressed in existing research regarding the usability of visual feedback. These results have implications for the design of future gaze selection techniques. A set of design principles was developed for designing new gaze selection techniques. The designers of gaze selection techniques can benefit from these design principles by applying them to their techniques
- Full Text:
- Date Issued: 2009
- Authors: Van Tonder, Martin Stephen
- Date: 2009
- Subjects: Human-computer interaction , User interfaces (Computer systems) , Gaze
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10469 , http://hdl.handle.net/10948/882 , Human-computer interaction , User interfaces (Computer systems) , Gaze
- Description: Eye gaze interaction enables users to interact with computers using their eyes. A wide variety of eye gaze interaction techniques have been developed to support this type of interaction. Gaze selection techniques, a class of eye gaze interaction techniques which support target selection, are the subject of this research. Researchers developing these techniques face a number of challenges. The most significant challenge is the limited accuracy of eye tracking equipment (due to the properties of the human eye). The design of gaze selection techniques is dominated by this constraint. Despite decades of research, existing techniques are still significantly less accurate than the mouse. A recently developed technique, EyePoint, represents the state of the art in gaze selection techniques. EyePoint combines gaze input with keyboard input. Evaluation results for this technique are encouraging, but accuracy is still a concern. Early trigger errors, resulting from users triggering a selection before looking at the intended target, were found to be the most commonly occurring errors for this technique. The primary goal of this research was to improve the usability of gaze selection techniques. In order to achieve this goal, novel gaze selection techniques were developed. New techniques were developed by combining elements of existing techniques in novel ways. Seven novel gaze selection techniques were developed. Three of these techniques were selected for evaluation. A software framework was developed for implementing and evaluating gaze selection techniques. This framework was used to implement the gaze selection techniques developed during this research. Implementing and evaluating all of the techniques using a common framework ensured consistency when comparing the techniques. The novel techniques which were developed were evaluated against EyePoint and the mouse using the framework. The three novel techniques evaluated were named TargetPoint, StaggerPoint and ScanPoint. TargetPoint combines motor space expansion with a visual feedback highlight whereas the StaggerPoint and TargetPoint designs explore novel approaches to target selection disambiguation. A usability evaluation of the three novel techniques alongside EyePoint and the mouse revealed some interesting trends. TargetPoint was found to be more usable and accurate than EyePoint. This novel technique also proved more popular with test participants. One aspect of TargetPoint which proved particularly popular was the visual feedback highlight, a feature which was found to be a more effective method of combating early trigger errors than existing approaches. StaggerPoint was more efficient than EyePoint, but was less effective and satisfying. ScanPoint was the least popular technique. The benefits of providing a visual feedback highlight and test participants' positive views thereof contradict views expressed in existing research regarding the usability of visual feedback. These results have implications for the design of future gaze selection techniques. A set of design principles was developed for designing new gaze selection techniques. The designers of gaze selection techniques can benefit from these design principles by applying them to their techniques
- Full Text:
- Date Issued: 2009
The development of a commercial production process for p-menthane-3,8-diol
- Authors: Rust, Nico
- Date: 2009
- Subjects: Insect pests -- Control , Repellents
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:10427 , http://hdl.handle.net/10948/d1018273
- Description: The synthesis of p-menthane-3,8-diol via the acid-catalyzed cyclization of citronellal in a dilute aqueous sulphuric acid medium was investigated using conventional batch and continuous systems in order to develop a commercial production process for said p-menthane-3,8-diol (PMD). The batch studies conducted during the first part of this study showed that the formation of PMD from citronellal occurs via an intra-molecular Prins reaction that results in the formation of both the desired PMD product, as well as the partially hydrated isopulegol. It was shown that the formationof the by- product, PMD-acetal, results from the reaction between an intermediate, 5-methyl-2- isopropylcyclohexanol, and the citronellal starting material, and not from the reaction between PMD and citronellal as previously reported. Kinetic studies confirmed the existence of a complicated kinetic model. The formation of PMD from citronellal displayed typical pseudo first order kinetics up to conversions of 70 after which the kinetic model becomes complicated as the result of the establishment of quasi equilibrium reactions between PMD and isopulegol (dehydration of PMD and hydration of isopulegol) and between PMD the PMD-acetal, both systems being acid catalysed. The PMD-acetal formation reaction appears to be second order with respect to PMD. Scale-up studies of the batch process to 30L and 50L scales showed that it would be extremely difficult to limit the level of PMD-acetal formation below the desired level of 1 percent, even if citronellal conversions are restricted to about 50 percent. During studies conducted on a commercially availablemicro-structured organic synthesis plant (OSP) it was shown that it is possible to perform the PMD reaction as a continuous process. The results obtained showed that the use of a micro-mixer such as the caterpillar micro-mixer did not provide enough residence time in order for desirable conversions (- 40 percent) to be obtained. By combining themicro-mixer with delay-loops of different thicknesses and lengths, and using increasing reaction temperatures, it was shown that the conversion of citronellal could be improved to some extent, but compared poorly to the expected conversions for a well-stirred batch reactor. By packing selected delay loops with inert SiC particles, improved mass transfer was observed between the organic and aqueous phases as reflected in the increased conversion of citronellal. Using the observations that were made during the use of the OSP, a continuous-flow, tubular reactor system was designed and constructed. Advanced statistical techniques were used to investigate the effect of variables such as temperature, acid concentration, reactor length, flow rate and the organic to aqueous ratio on the rate and selectivity of the reaction. Mathematical models were derived for citronellal conversion, yield of PMD and yield of PMD- acetals, and used to predict the concentrations of citronellal, PMD and PMD-acetals at set experimental conditions. The results obtained showed that it was possible to obtain a product which approached desired specifications.Downstream processing of the PMD reaction mixture as it exits the reactor requires phase separation and neutralization of the acid catalyst solution, followed by further work-up to recover unreacted starting material and intermediates for recycle back to the synthesis reactor, followed by purification of crude PMD to the desired specification. The study showed that neutralization, prior or after phase separation, does not affect the selectivity of the PMD to such a great extent, but does influence the relative conversion due to extended contact of the catalyst with the organic phase after the reaction is terminated. Recovery of unreacted citronellal and isopulegol could be achieved by a simple vacuum evaporation step, which may either be carried out in a batch manner using traditional distillation equipment, or in a continuous process using wiped-film (short path) techniques. It was also shown that selective crystallization of PMD from the crude product mixture by addition of a solvent, such as heptanes or hexane proved to be the best way of achieving the desired product specification.
- Full Text:
- Date Issued: 2009
- Authors: Rust, Nico
- Date: 2009
- Subjects: Insect pests -- Control , Repellents
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:10427 , http://hdl.handle.net/10948/d1018273
- Description: The synthesis of p-menthane-3,8-diol via the acid-catalyzed cyclization of citronellal in a dilute aqueous sulphuric acid medium was investigated using conventional batch and continuous systems in order to develop a commercial production process for said p-menthane-3,8-diol (PMD). The batch studies conducted during the first part of this study showed that the formation of PMD from citronellal occurs via an intra-molecular Prins reaction that results in the formation of both the desired PMD product, as well as the partially hydrated isopulegol. It was shown that the formationof the by- product, PMD-acetal, results from the reaction between an intermediate, 5-methyl-2- isopropylcyclohexanol, and the citronellal starting material, and not from the reaction between PMD and citronellal as previously reported. Kinetic studies confirmed the existence of a complicated kinetic model. The formation of PMD from citronellal displayed typical pseudo first order kinetics up to conversions of 70 after which the kinetic model becomes complicated as the result of the establishment of quasi equilibrium reactions between PMD and isopulegol (dehydration of PMD and hydration of isopulegol) and between PMD the PMD-acetal, both systems being acid catalysed. The PMD-acetal formation reaction appears to be second order with respect to PMD. Scale-up studies of the batch process to 30L and 50L scales showed that it would be extremely difficult to limit the level of PMD-acetal formation below the desired level of 1 percent, even if citronellal conversions are restricted to about 50 percent. During studies conducted on a commercially availablemicro-structured organic synthesis plant (OSP) it was shown that it is possible to perform the PMD reaction as a continuous process. The results obtained showed that the use of a micro-mixer such as the caterpillar micro-mixer did not provide enough residence time in order for desirable conversions (- 40 percent) to be obtained. By combining themicro-mixer with delay-loops of different thicknesses and lengths, and using increasing reaction temperatures, it was shown that the conversion of citronellal could be improved to some extent, but compared poorly to the expected conversions for a well-stirred batch reactor. By packing selected delay loops with inert SiC particles, improved mass transfer was observed between the organic and aqueous phases as reflected in the increased conversion of citronellal. Using the observations that were made during the use of the OSP, a continuous-flow, tubular reactor system was designed and constructed. Advanced statistical techniques were used to investigate the effect of variables such as temperature, acid concentration, reactor length, flow rate and the organic to aqueous ratio on the rate and selectivity of the reaction. Mathematical models were derived for citronellal conversion, yield of PMD and yield of PMD- acetals, and used to predict the concentrations of citronellal, PMD and PMD-acetals at set experimental conditions. The results obtained showed that it was possible to obtain a product which approached desired specifications.Downstream processing of the PMD reaction mixture as it exits the reactor requires phase separation and neutralization of the acid catalyst solution, followed by further work-up to recover unreacted starting material and intermediates for recycle back to the synthesis reactor, followed by purification of crude PMD to the desired specification. The study showed that neutralization, prior or after phase separation, does not affect the selectivity of the PMD to such a great extent, but does influence the relative conversion due to extended contact of the catalyst with the organic phase after the reaction is terminated. Recovery of unreacted citronellal and isopulegol could be achieved by a simple vacuum evaporation step, which may either be carried out in a batch manner using traditional distillation equipment, or in a continuous process using wiped-film (short path) techniques. It was also shown that selective crystallization of PMD from the crude product mixture by addition of a solvent, such as heptanes or hexane proved to be the best way of achieving the desired product specification.
- Full Text:
- Date Issued: 2009
The development of a practical diet for juvenile dusky kob, Argyrosomus japonicus, for the South African mariculture industry
- Authors: Woolley, Lindsey
- Date: 2009
- Subjects: Fishes -- Nutrition -- Requirements , Fishes -- Food , Fishes -- Growth , Fish culture , Argyrosomus -- Nutrition , Sciaenidae -- Nutrition
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5257 , http://hdl.handle.net/10962/d1005100 , Fishes -- Nutrition -- Requirements , Fishes -- Food , Fishes -- Growth , Fish culture , Argyrosomus -- Nutrition , Sciaenidae -- Nutrition
- Description: The lack of locally manufactured marine finfish diets motivated the current project, which aimed to develop a practical diet specifically formulated for dusky kob. The first growth trial investigated the effect of pellet texture (i.e. hard versus soft pellets) and the inclusion of an additional binder, test treatments were compared to two reference diets. There was no significant difference in weight gain between fish fed the hard or soft pellets (p=0.17), over nine weeks. The fish fed the local trout feed weighed significantly less than those fed the test diets (p=0.003). There was no significant difference in leaching rate amongst treatments (p=0.45). A hard pelleted diet without gelatin is recommended in the commercial culture of dusky kob. Pellets with different physical shapes were tested to determine the effect of shape on settling speeds. A square shaped pellet had a slower sinking rate compared to a round shaped pellet (p<0.0001). Juvenile dusky kob, held in cages, fed the square pellets grew significantly faster than the fish fed the round pellet, with a mean weight gain of 16.81 ± 0.45 g (p=0.018). A growth trial was used to optimize the protein to energy (PE) ratio by adjusting dietary protein and lipid levels. Fish fed the diets with high levels of protein (46 % protein) achieved the better growth rates (125 % weight gain) compared to the lower protein diets (92 % weight gain) (p<0.0001). There was no significant difference in total ammonia production (TAN) level for the 46 and 42 % protein diets (p=0.68). The overall performance of the prototype diet was investigated in a closed recirculating system. Growth and FCR of the fish fed the prototype diet was on a par to those fed the commercially available diet currently used in the local farming industry. There was no significant difference in the blood chemistry for fish held at increased stocking densities. The prototype diet is suitable for use in recirculating systems, as there were no negative effects on water quality parameters. This study has laid a foundation for the manufacture of a practical commercial dusky kob diet in South Africa.
- Full Text:
- Date Issued: 2009
- Authors: Woolley, Lindsey
- Date: 2009
- Subjects: Fishes -- Nutrition -- Requirements , Fishes -- Food , Fishes -- Growth , Fish culture , Argyrosomus -- Nutrition , Sciaenidae -- Nutrition
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5257 , http://hdl.handle.net/10962/d1005100 , Fishes -- Nutrition -- Requirements , Fishes -- Food , Fishes -- Growth , Fish culture , Argyrosomus -- Nutrition , Sciaenidae -- Nutrition
- Description: The lack of locally manufactured marine finfish diets motivated the current project, which aimed to develop a practical diet specifically formulated for dusky kob. The first growth trial investigated the effect of pellet texture (i.e. hard versus soft pellets) and the inclusion of an additional binder, test treatments were compared to two reference diets. There was no significant difference in weight gain between fish fed the hard or soft pellets (p=0.17), over nine weeks. The fish fed the local trout feed weighed significantly less than those fed the test diets (p=0.003). There was no significant difference in leaching rate amongst treatments (p=0.45). A hard pelleted diet without gelatin is recommended in the commercial culture of dusky kob. Pellets with different physical shapes were tested to determine the effect of shape on settling speeds. A square shaped pellet had a slower sinking rate compared to a round shaped pellet (p<0.0001). Juvenile dusky kob, held in cages, fed the square pellets grew significantly faster than the fish fed the round pellet, with a mean weight gain of 16.81 ± 0.45 g (p=0.018). A growth trial was used to optimize the protein to energy (PE) ratio by adjusting dietary protein and lipid levels. Fish fed the diets with high levels of protein (46 % protein) achieved the better growth rates (125 % weight gain) compared to the lower protein diets (92 % weight gain) (p<0.0001). There was no significant difference in total ammonia production (TAN) level for the 46 and 42 % protein diets (p=0.68). The overall performance of the prototype diet was investigated in a closed recirculating system. Growth and FCR of the fish fed the prototype diet was on a par to those fed the commercially available diet currently used in the local farming industry. There was no significant difference in the blood chemistry for fish held at increased stocking densities. The prototype diet is suitable for use in recirculating systems, as there were no negative effects on water quality parameters. This study has laid a foundation for the manufacture of a practical commercial dusky kob diet in South Africa.
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- Date Issued: 2009