Enabling e-learning 2.0 in information security education: a semantic web approach
- Authors: Goss, Ryan Gavin
- Date: 2009
- Subjects: Data protection , Computers -- Access control , Electronic data processing -- Security measures , Electronic data processing departments -- Security measures
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9771 , http://hdl.handle.net/10948/909 , Data protection , Computers -- Access control , Electronic data processing -- Security measures , Electronic data processing departments -- Security measures
- Description: The motivation for this study argued that current information security ed- ucation systems are inadequate for educating all users of computer systems world wide in acting securely during their operations with information sys- tems. There is, therefore, a pervasive need for information security knowledge in all aspects of modern life. E-Learning 2.0 could possi- bly contribute to solving this problem, however, little or no knowledge currently exists regarding the suitability and practicality of using such systems to infer information security knowledge to learners.
- Full Text:
- Date Issued: 2009
- Authors: Goss, Ryan Gavin
- Date: 2009
- Subjects: Data protection , Computers -- Access control , Electronic data processing -- Security measures , Electronic data processing departments -- Security measures
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9771 , http://hdl.handle.net/10948/909 , Data protection , Computers -- Access control , Electronic data processing -- Security measures , Electronic data processing departments -- Security measures
- Description: The motivation for this study argued that current information security ed- ucation systems are inadequate for educating all users of computer systems world wide in acting securely during their operations with information sys- tems. There is, therefore, a pervasive need for information security knowledge in all aspects of modern life. E-Learning 2.0 could possi- bly contribute to solving this problem, however, little or no knowledge currently exists regarding the suitability and practicality of using such systems to infer information security knowledge to learners.
- Full Text:
- Date Issued: 2009
Enhancing learner centred education through the eco-schools framework: case studies of eco-schools practice in South Africa and Namibia
- Authors: Haingura, Rudolph
- Date: 2009
- Subjects: Education -- South Africa -- Case studies Education -- Namibia -- Case studies Educational change -- South Africa -- Case studies Educational change -- Namibia -- Case studies Teachers -- Training of -- South Africa -- Case studies Teachers -- Training of -- Namibia -- Case studies Environmental education -- South Africa -- Case studies Environmental education -- Namibia -- Case studies School improvement programs
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1509 , http://hdl.handle.net/10962/d1003391
- Description: Since the early 1990’s both South Africa and Namibia have been engaged in educational reform processes to address the discriminatory impacts and orientations of education under Bantu Education which were implemented in both countries prior to independence (Namibia in 1990, and South Africa in 1994). A feature of both educational reform processes is the underpinning theory of learning which draws on social constructivism, and which is articulated as learner centred education. This approach to teaching and learning infuses both policy frameworks. Another common feature is the introduction of environmental education into the formal education systems of both countries, a process which has been championed by development assistance, and which has been supported by programmes such as the Eco-Schools programme which is an international environmental education initiative started after the Rio Earth Summit in 1992, and implemented in a number of countries, including South Africa. The programme has also been piloted in some schools in Namibia. To date no research has been done on the way in which the Eco-Schools framework (its practices, organizing principles, evaluation processes etc.) enhance learner centred education. This study therefore aimed to investigate and understand how the Eco-Schools framework can enhance learner centred education. The study was conducted in 2007 in three Eco-Schools in Namibia and four Eco-Schools in South Africa in the context of the broader national programmes of implementing learner centred education policies, and environmental education histories. The study used a case study methodology, using observation, interviews, and document analysis as the main methods for data generation. The analytical process followed two stages: the first involved an inductive analysis using categories which were organized into a series of analytical memos. The second phase of data analysis involved recontextualising the data drawing on theory and contextual insights to provide insights that address the research question, using analytical statements. The main findings of the study are that the Eco-Schools framework provides numerous opportunities to enhance learner centred education, through contextualization of learning, through strengthening school-community interactions, and through enabling active involvement of learners in decision making and a range of contextually meaningful Eco-Schools practices. The study also showed that the Eco-Schools framework allows for empowerment of learners in relation to diverse needs, and also allows for learner initiated contributions, although this aspect was not well developed in the schools that were included in this study. The study also found that the benefits of Eco-Schools in terms of enhancing learner centred education were limited to only a few learners who were involved in club activities or who were being taught by enthusiastic teachers who were participating in the Eco-Schools programme. The study showed that these benefits can be more widely shared if more teachers were to get involved, and if the Eco-Schools programme were better understood in relation to the curriculum requirements of various subjects and learning areas, and if the Eco-Schools practices could be more successfully integrated across the curriculum. The study also showed that various forms of support were required for implementing the Eco-Schools programme, most notably the support of the Principal, and the Department of Education. The study also identified that parents and other stakeholders in the school were supportive of the Eco-Schools programme since it was perceived to have relevance to learning, as well as the community. The results broadly confirmed that the implementation of Eco-Schools using a whole school, values based and active learning approach promotes a school culture which enhances learner centred education more broadly across the school. The study also found that the Eco-Schools programme added a new dimension to existing discourses on learner centred education, which could be described as a community linked or situated approach to learner centred education.
- Full Text:
- Date Issued: 2009
- Authors: Haingura, Rudolph
- Date: 2009
- Subjects: Education -- South Africa -- Case studies Education -- Namibia -- Case studies Educational change -- South Africa -- Case studies Educational change -- Namibia -- Case studies Teachers -- Training of -- South Africa -- Case studies Teachers -- Training of -- Namibia -- Case studies Environmental education -- South Africa -- Case studies Environmental education -- Namibia -- Case studies School improvement programs
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1509 , http://hdl.handle.net/10962/d1003391
- Description: Since the early 1990’s both South Africa and Namibia have been engaged in educational reform processes to address the discriminatory impacts and orientations of education under Bantu Education which were implemented in both countries prior to independence (Namibia in 1990, and South Africa in 1994). A feature of both educational reform processes is the underpinning theory of learning which draws on social constructivism, and which is articulated as learner centred education. This approach to teaching and learning infuses both policy frameworks. Another common feature is the introduction of environmental education into the formal education systems of both countries, a process which has been championed by development assistance, and which has been supported by programmes such as the Eco-Schools programme which is an international environmental education initiative started after the Rio Earth Summit in 1992, and implemented in a number of countries, including South Africa. The programme has also been piloted in some schools in Namibia. To date no research has been done on the way in which the Eco-Schools framework (its practices, organizing principles, evaluation processes etc.) enhance learner centred education. This study therefore aimed to investigate and understand how the Eco-Schools framework can enhance learner centred education. The study was conducted in 2007 in three Eco-Schools in Namibia and four Eco-Schools in South Africa in the context of the broader national programmes of implementing learner centred education policies, and environmental education histories. The study used a case study methodology, using observation, interviews, and document analysis as the main methods for data generation. The analytical process followed two stages: the first involved an inductive analysis using categories which were organized into a series of analytical memos. The second phase of data analysis involved recontextualising the data drawing on theory and contextual insights to provide insights that address the research question, using analytical statements. The main findings of the study are that the Eco-Schools framework provides numerous opportunities to enhance learner centred education, through contextualization of learning, through strengthening school-community interactions, and through enabling active involvement of learners in decision making and a range of contextually meaningful Eco-Schools practices. The study also showed that the Eco-Schools framework allows for empowerment of learners in relation to diverse needs, and also allows for learner initiated contributions, although this aspect was not well developed in the schools that were included in this study. The study also found that the benefits of Eco-Schools in terms of enhancing learner centred education were limited to only a few learners who were involved in club activities or who were being taught by enthusiastic teachers who were participating in the Eco-Schools programme. The study showed that these benefits can be more widely shared if more teachers were to get involved, and if the Eco-Schools programme were better understood in relation to the curriculum requirements of various subjects and learning areas, and if the Eco-Schools practices could be more successfully integrated across the curriculum. The study also showed that various forms of support were required for implementing the Eco-Schools programme, most notably the support of the Principal, and the Department of Education. The study also identified that parents and other stakeholders in the school were supportive of the Eco-Schools programme since it was perceived to have relevance to learning, as well as the community. The results broadly confirmed that the implementation of Eco-Schools using a whole school, values based and active learning approach promotes a school culture which enhances learner centred education more broadly across the school. The study also found that the Eco-Schools programme added a new dimension to existing discourses on learner centred education, which could be described as a community linked or situated approach to learner centred education.
- Full Text:
- Date Issued: 2009
Environmental education policy support in Southern Africa: a case story of SADC REEP
- Gumede, Sibusisiwe Marie-Louise
- Authors: Gumede, Sibusisiwe Marie-Louise
- Date: 2009
- Subjects: SADC Regional Environmental Education Programme Environmental education -- Africa, Southern Education -- Africa, Southern Education and state -- Africa, Southern Teaching -- Aids and devices -- Africa, Southern
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1515 , http://hdl.handle.net/10962/d1003397
- Description: The study takes place in the context of the Southern African Development Community’s Regional Environmental Education Programme (SADC REEP). The SADC REEP is a programme of the Food Agriculture and Natural Resources Directorate of the SADC Secretariat. The programme is implemented through four components namely policy, networking, training and learning support materials development. The bulk of the policy budget is in the form of seed funding to support policy initiatives in the member states. The intention of this study is to illuminate factors that influence the deployment and use of seed funding to support environmental education policy processes within the SADC REEP. To sharpen the understanding of the context within which these activities take place, the study looks at the global and regional landscape of policy events and their influence on policy in the sub-region. The study also looks at the landscape of the fields within which environmental education is embedded, the power relations, and the notion of agency in environmental education policy processes. The discourse in environmental education policy processes is analyzed by drawing on Bourdieu’s constructivist structuralism to highlight some of the social and institutional complexities in dynamic fields, capital and policy context. The research takes a qualitative interpretative approach using case study methodology to explore the processes and influences that have a bearing on the SADC REEP policy sub-component, specifically the deployment and use of seed funding for policy initiatives. The findings show the complexity of the variables at play in shaping the processes of developing and reviewing environmental education policies in the sub-region. These variables include discourse that is used, economics and politics of the responsible institutions and actors, as well as relationships between the environmental field and education field. The results point towards a need to clearly understand the policy context within which the SADC REEP is operating in order to make correct assumptions, to develop realist expectations, and to put in place appropriate mechanisms that will effect the expectations. The study recommends further probing of the relationship between the actors and networks in relation to the success of policy processes. It also recommends a further exploration of the SADC REEP’s open-ended approach with respect to articulating the monitoring and consolidation of the successes in supporting environmental education policy processes.
- Full Text:
- Date Issued: 2009
- Authors: Gumede, Sibusisiwe Marie-Louise
- Date: 2009
- Subjects: SADC Regional Environmental Education Programme Environmental education -- Africa, Southern Education -- Africa, Southern Education and state -- Africa, Southern Teaching -- Aids and devices -- Africa, Southern
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1515 , http://hdl.handle.net/10962/d1003397
- Description: The study takes place in the context of the Southern African Development Community’s Regional Environmental Education Programme (SADC REEP). The SADC REEP is a programme of the Food Agriculture and Natural Resources Directorate of the SADC Secretariat. The programme is implemented through four components namely policy, networking, training and learning support materials development. The bulk of the policy budget is in the form of seed funding to support policy initiatives in the member states. The intention of this study is to illuminate factors that influence the deployment and use of seed funding to support environmental education policy processes within the SADC REEP. To sharpen the understanding of the context within which these activities take place, the study looks at the global and regional landscape of policy events and their influence on policy in the sub-region. The study also looks at the landscape of the fields within which environmental education is embedded, the power relations, and the notion of agency in environmental education policy processes. The discourse in environmental education policy processes is analyzed by drawing on Bourdieu’s constructivist structuralism to highlight some of the social and institutional complexities in dynamic fields, capital and policy context. The research takes a qualitative interpretative approach using case study methodology to explore the processes and influences that have a bearing on the SADC REEP policy sub-component, specifically the deployment and use of seed funding for policy initiatives. The findings show the complexity of the variables at play in shaping the processes of developing and reviewing environmental education policies in the sub-region. These variables include discourse that is used, economics and politics of the responsible institutions and actors, as well as relationships between the environmental field and education field. The results point towards a need to clearly understand the policy context within which the SADC REEP is operating in order to make correct assumptions, to develop realist expectations, and to put in place appropriate mechanisms that will effect the expectations. The study recommends further probing of the relationship between the actors and networks in relation to the success of policy processes. It also recommends a further exploration of the SADC REEP’s open-ended approach with respect to articulating the monitoring and consolidation of the successes in supporting environmental education policy processes.
- Full Text:
- Date Issued: 2009
Epistemological access as an open question in education
- Authors: Lotz-Sisitka, Heila
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:21219 , http://hdl.handle.net/10962/7123 , http://joe.ukzn.ac.za/Libraries/No_46_June_2009/Epistemological_access_as_an_open_question_in_education.sflb.ashx
- Description: In his book Learning to Teach in South Africa Morrow (2007)1 argues that teacher education’s ultimate aim is to enable epistemological access2 to knowledge in the modern world, and that there is a need to find new ways of thinking about teaching in South Africa if we are to meet the challenge of enabling all learners to gain such epistemological access. Morrow relates problems of epistemological access to the dominance of an empiricist epistemology in education, and he also comments on how this is obscured by the ideologies of Outcomes Based Education and learner-centred education (with attendant constructivist, relativist assumptions about knowledge). These problems, he argues, have come to shape curriculum thinking, and hence teaching practice, creating a muddled epistemological context in which teaching practices are taking place. He argues for a realist focus but he does not elaborate on what such a realist focus might mean for enabling epistemological access or for associated teaching practice or for teacher education. He does, however, propose that systematic learning is a necessary way forward.
- Full Text:
- Date Issued: 2009
- Authors: Lotz-Sisitka, Heila
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:21219 , http://hdl.handle.net/10962/7123 , http://joe.ukzn.ac.za/Libraries/No_46_June_2009/Epistemological_access_as_an_open_question_in_education.sflb.ashx
- Description: In his book Learning to Teach in South Africa Morrow (2007)1 argues that teacher education’s ultimate aim is to enable epistemological access2 to knowledge in the modern world, and that there is a need to find new ways of thinking about teaching in South Africa if we are to meet the challenge of enabling all learners to gain such epistemological access. Morrow relates problems of epistemological access to the dominance of an empiricist epistemology in education, and he also comments on how this is obscured by the ideologies of Outcomes Based Education and learner-centred education (with attendant constructivist, relativist assumptions about knowledge). These problems, he argues, have come to shape curriculum thinking, and hence teaching practice, creating a muddled epistemological context in which teaching practices are taking place. He argues for a realist focus but he does not elaborate on what such a realist focus might mean for enabling epistemological access or for associated teaching practice or for teacher education. He does, however, propose that systematic learning is a necessary way forward.
- Full Text:
- Date Issued: 2009
eServices provisioning in a community development context through a JADE MAS platform
- Thinyane, Mamello, Terzoli, Alfredo, Clayton, Peter G
- Authors: Thinyane, Mamello , Terzoli, Alfredo , Clayton, Peter G
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430836 , vital:72720 , 10.1109/ICTD.2009.5426697
- Description: A growing proliferation of ICT4D interventions has necessitated the ex-ploration of innovative solutions for the provisioning of eServices in ru-ral, marginalized communities. The challenges currently faced in these interventions include: situating the developed applications within the cultural and ethnographic context of the target communities, integrating greater levels of granularity and flexibility within the applications for in-creased context sensitivity, handling the intermittence and instability of supporting infrastructural services. These are the challenges that we address in the context of ICT4D intervention undertaken in a rural community in the Eastern Cape province of South Africa. We explore the design and implementation of a Multi-Agent System (MAS) for this community as a platform for provisioning of context-sensitive eServ-ices, and highlight some observations with regards to the applicability and adequacy of the solution.
- Full Text:
- Date Issued: 2009
- Authors: Thinyane, Mamello , Terzoli, Alfredo , Clayton, Peter G
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430836 , vital:72720 , 10.1109/ICTD.2009.5426697
- Description: A growing proliferation of ICT4D interventions has necessitated the ex-ploration of innovative solutions for the provisioning of eServices in ru-ral, marginalized communities. The challenges currently faced in these interventions include: situating the developed applications within the cultural and ethnographic context of the target communities, integrating greater levels of granularity and flexibility within the applications for in-creased context sensitivity, handling the intermittence and instability of supporting infrastructural services. These are the challenges that we address in the context of ICT4D intervention undertaken in a rural community in the Eastern Cape province of South Africa. We explore the design and implementation of a Multi-Agent System (MAS) for this community as a platform for provisioning of context-sensitive eServ-ices, and highlight some observations with regards to the applicability and adequacy of the solution.
- Full Text:
- Date Issued: 2009
Establishing experimental systems for studying the replication biology of Providence virus
- Authors: Walter, Cheryl Tracy
- Date: 2009
- Subjects: Insects -- Viruses Insects -- Diseases Insects -- Parasites Host-virus relationships RNA viruses DNA Insects as carriers of disease
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3928 , http://hdl.handle.net/10962/d1003987
- Description: Providence virus (PrV) is a member of the Tetraviridae, a family of small, positive sense, single-stranded RNA viruses, which characteristically infect the midgut tissue of heliothine larvae. PrV is the only known tetravirus that replicates in cultured insect cells. The virus comprises a monopartite genome resembling members of the genus Betatetravirus with the capsid precursor protein undergoing autoproteolytic cleavage at its C-terminus consistent with other tetravirus capsid precursor proteins. Analysis of viral cDNA predicted the presence of three potential overlapping gene products (from 5` to 3`): (1) p130, a protein of unrecognized nucleotide or amino acid homology with a 2A-like processing site at its N-terminus; (2) p104, the replicase ORF, which was found to be phylogenetically related to tombus-and umbraviruses replicases. The presence of a read-through stop signal in the p104 ORF was proposed to produce and amino terminal product with a predicted MW of 40 kDa (p40) and (3) the capsid protein precursor (81 kDa) which has two 2A-like processing sites at its N-terminus. Metabolic radiolabelling of viral translation products in persistently infected MG8 cells and in vitro translation of the individual ORFs were performed in order to analyse the expression of PrV gene products. p130 was translated with no evidence of 2A-like processing. Two products of 40 kDa and 104 kDa were translated from the p104 ORF, indicating that the read-through stop signal was likely to be functional. Finally, the capsid protein precursor ORF produced a major translation product of 68 kDa corresponding to the capsid protein precursor as well a peptide of 15 kDa that was attributed to the activity of the second 2A-like site at the N-terminus of the p81 ORF. The subcellular distribution of viral RNA (vRNA) and p40 in MG8 cells was investigated using immunofluorescence and biochemical fractionation. The results showed that p40/p104 and vRNA accumulated in polarized, punctate structures in some but not all MG8 cells and in some cases, co-localization was observed. This thesis concludes that PrV is a novel tetravirus with significant similarities plant carmolike viruses that should be re-classified at the family level.
- Full Text:
- Date Issued: 2009
- Authors: Walter, Cheryl Tracy
- Date: 2009
- Subjects: Insects -- Viruses Insects -- Diseases Insects -- Parasites Host-virus relationships RNA viruses DNA Insects as carriers of disease
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3928 , http://hdl.handle.net/10962/d1003987
- Description: Providence virus (PrV) is a member of the Tetraviridae, a family of small, positive sense, single-stranded RNA viruses, which characteristically infect the midgut tissue of heliothine larvae. PrV is the only known tetravirus that replicates in cultured insect cells. The virus comprises a monopartite genome resembling members of the genus Betatetravirus with the capsid precursor protein undergoing autoproteolytic cleavage at its C-terminus consistent with other tetravirus capsid precursor proteins. Analysis of viral cDNA predicted the presence of three potential overlapping gene products (from 5` to 3`): (1) p130, a protein of unrecognized nucleotide or amino acid homology with a 2A-like processing site at its N-terminus; (2) p104, the replicase ORF, which was found to be phylogenetically related to tombus-and umbraviruses replicases. The presence of a read-through stop signal in the p104 ORF was proposed to produce and amino terminal product with a predicted MW of 40 kDa (p40) and (3) the capsid protein precursor (81 kDa) which has two 2A-like processing sites at its N-terminus. Metabolic radiolabelling of viral translation products in persistently infected MG8 cells and in vitro translation of the individual ORFs were performed in order to analyse the expression of PrV gene products. p130 was translated with no evidence of 2A-like processing. Two products of 40 kDa and 104 kDa were translated from the p104 ORF, indicating that the read-through stop signal was likely to be functional. Finally, the capsid protein precursor ORF produced a major translation product of 68 kDa corresponding to the capsid protein precursor as well a peptide of 15 kDa that was attributed to the activity of the second 2A-like site at the N-terminus of the p81 ORF. The subcellular distribution of viral RNA (vRNA) and p40 in MG8 cells was investigated using immunofluorescence and biochemical fractionation. The results showed that p40/p104 and vRNA accumulated in polarized, punctate structures in some but not all MG8 cells and in some cases, co-localization was observed. This thesis concludes that PrV is a novel tetravirus with significant similarities plant carmolike viruses that should be re-classified at the family level.
- Full Text:
- Date Issued: 2009
Establishing explicit perspectives of personality for a sample of Xhosa-speaking South Africans
- Authors: Nopote, Nomvuyiseko Minty
- Date: 2009
- Subjects: Personality assessment -- South Africa Cross-cultural studies , Psychological tests -- South Africa -- Cross-cultural studies , Language and languages -- Ability testing -- South Africa , Xhosa language -- South Africa -- Comparison
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9892 , http://hdl.handle.net/10948/1145 , Personality assessment -- South Africa Cross-cultural studies , Psychological tests -- South Africa -- Cross-cultural studies , Language and languages -- Ability testing -- South Africa , Xhosa language -- South Africa -- Comparison
- Description: Cross-cultural assessment in South Africa has become more prominent since the first democratic elections held in April 1994, as stronger demands for the cultural appropriateness of psychological tests have been made. The use of psychometric testing, including personality assessment in the workplace, is now strictly controlled by legislation, among others the Constitution of the Republic of South Africa (Act 108 of 1996), the Labour Relations Act (66 of 1995), and the Employment Equity Act (55 of 1998), and the Health Professions Act (56 of 1974). The present study forms part of the development process of the South African Personality Inventory (SAPI), which seeks to explore the indigenous personality structure of all the 11 official language groups found in South Africa and to then develop a personality inventory based on this. The present study aimed to explore and describe the personality facets and clusters that were found among a sample of 95 Xhosa-speaking South Africans. An exploratory descriptive research method was used and participants were selected by means of non-probability purposive sampling. Data were gathered by administering a biographical questionnaire and a tape-recorded 10- item interview questionnaire. Content analysis was used to analyse and reduce the data obtained from interviews into personality descriptors. Of the 1872 personality-descriptive words obtained from the interview questions, 164 facets of different personality characteristics were finally configured as a consequence of a data-reduction process. These facets were further categorised into a total of 37 personality sub-clusters and nine personality clusters which were labelled as Extraversion, Soft-heartedness, Conscientiousness, Emotional Stability, Intellect, Openness, Integrity, Relationship Harmony and Facilitating. These clusters and their sub-clusters resonate well with significant aspects and values of the Xhosa culture (e.g., Ubuntu). There also seems to be a moderate correspondence between the clusters and sub-clusters identified in the Xhosa-speaking sample and factors of the Five-Factor Model, especially with respect to the six clusters of Extraversion, Soft-heartedness, Conscientiousness, Emotional Stability, Intellect, and Openness. Nonetheless, differences in the composition of the clusters/facets were found, some of which are due to the more unique facets and sub-facets of personality identified in the Xhosa-speaking sample. The limitations of the study are identified and suggestions are made for further research.
- Full Text:
- Date Issued: 2009
- Authors: Nopote, Nomvuyiseko Minty
- Date: 2009
- Subjects: Personality assessment -- South Africa Cross-cultural studies , Psychological tests -- South Africa -- Cross-cultural studies , Language and languages -- Ability testing -- South Africa , Xhosa language -- South Africa -- Comparison
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9892 , http://hdl.handle.net/10948/1145 , Personality assessment -- South Africa Cross-cultural studies , Psychological tests -- South Africa -- Cross-cultural studies , Language and languages -- Ability testing -- South Africa , Xhosa language -- South Africa -- Comparison
- Description: Cross-cultural assessment in South Africa has become more prominent since the first democratic elections held in April 1994, as stronger demands for the cultural appropriateness of psychological tests have been made. The use of psychometric testing, including personality assessment in the workplace, is now strictly controlled by legislation, among others the Constitution of the Republic of South Africa (Act 108 of 1996), the Labour Relations Act (66 of 1995), and the Employment Equity Act (55 of 1998), and the Health Professions Act (56 of 1974). The present study forms part of the development process of the South African Personality Inventory (SAPI), which seeks to explore the indigenous personality structure of all the 11 official language groups found in South Africa and to then develop a personality inventory based on this. The present study aimed to explore and describe the personality facets and clusters that were found among a sample of 95 Xhosa-speaking South Africans. An exploratory descriptive research method was used and participants were selected by means of non-probability purposive sampling. Data were gathered by administering a biographical questionnaire and a tape-recorded 10- item interview questionnaire. Content analysis was used to analyse and reduce the data obtained from interviews into personality descriptors. Of the 1872 personality-descriptive words obtained from the interview questions, 164 facets of different personality characteristics were finally configured as a consequence of a data-reduction process. These facets were further categorised into a total of 37 personality sub-clusters and nine personality clusters which were labelled as Extraversion, Soft-heartedness, Conscientiousness, Emotional Stability, Intellect, Openness, Integrity, Relationship Harmony and Facilitating. These clusters and their sub-clusters resonate well with significant aspects and values of the Xhosa culture (e.g., Ubuntu). There also seems to be a moderate correspondence between the clusters and sub-clusters identified in the Xhosa-speaking sample and factors of the Five-Factor Model, especially with respect to the six clusters of Extraversion, Soft-heartedness, Conscientiousness, Emotional Stability, Intellect, and Openness. Nonetheless, differences in the composition of the clusters/facets were found, some of which are due to the more unique facets and sub-facets of personality identified in the Xhosa-speaking sample. The limitations of the study are identified and suggestions are made for further research.
- Full Text:
- Date Issued: 2009
Establishment of translocated populations of smallmouth yellowfish, Labeobarbus aeneus (Pisces: Cyprinidae), in lentic and lotic habitats in the Great Fish River system, South Africa
- Weyl, Olaf L F, Stadtlander, Timo, Booth, Anthony J
- Authors: Weyl, Olaf L F , Stadtlander, Timo , Booth, Anthony J
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124418 , vital:35607 , https://doi.org/10.3377/004.044.0109
- Description: As a result of numerous introductions and translocations of fishes, South Africa has recently been identified as a fish invasion hotspot (Leprieur et al. 2008). In freshwater ecosystems invasion by alien species is considered a leading mechanism driving environmental change (Clavero & Garcia- Berthou 2005; Garcia-Berthou et al. 2005). In South Africa, documented effects of fish invasions include the extirpation of indigenous fishes through predation (Cambray 2003), changes in invertebrate community structure (Lowe et al. 2008) and hybridization (Canonico et al. 2005). As a result, the management of alien species is a high national priority (National Environmental Management: Biodiversity Act 2004). Such management requires an understanding of the biology, ecology and establishment success of fishes outside their native range.
- Full Text:
- Date Issued: 2009
- Authors: Weyl, Olaf L F , Stadtlander, Timo , Booth, Anthony J
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124418 , vital:35607 , https://doi.org/10.3377/004.044.0109
- Description: As a result of numerous introductions and translocations of fishes, South Africa has recently been identified as a fish invasion hotspot (Leprieur et al. 2008). In freshwater ecosystems invasion by alien species is considered a leading mechanism driving environmental change (Clavero & Garcia- Berthou 2005; Garcia-Berthou et al. 2005). In South Africa, documented effects of fish invasions include the extirpation of indigenous fishes through predation (Cambray 2003), changes in invertebrate community structure (Lowe et al. 2008) and hybridization (Canonico et al. 2005). As a result, the management of alien species is a high national priority (National Environmental Management: Biodiversity Act 2004). Such management requires an understanding of the biology, ecology and establishment success of fishes outside their native range.
- Full Text:
- Date Issued: 2009
Ethical decision-making in the therapeutic space : a psychoanalytic view
- Authors: Silove, Melanie
- Date: 2009
- Subjects: Decision making -- Moral and ethical aspects , Psychotherapy -- Moral and ethical aspects , Psychotherapists -- Professional ethics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3273 , http://hdl.handle.net/10962/d1020873
- Description: This study examined the ethical decision-making process as it transpired in the everyday context of the therapeutic space. In-depth interviews explored the subjective experiences of six South African psychologists, practicing as psychoanalytic psychotherapists, and their efforts to resolve real-life ethical dilemmas. The theoretical framework used to interpret the data subsumed professional literature in psychology on principle-based ethical decision-making as well as contemporary psychoanalytic debates on the phenomenon of countertransference enactments. A review of ethics codes, survey research and seminal decision-making frameworks suggests that ethical dilemmas have traditionally been resolved by recourse to an objective and impartial “principle ethics” perspective. Empirical evidence shows, however, that logical thinking and the rational application of codes, principles and standards are often insufficient to secure ethical action. The establishment of reflective space and the core theoretical notion of “ethical decision-making enactments” were proposed in order to address the subjective, irrational and unconscious dimension of professional decision-making. This study used a broadly hermeneutic research method which transformed participants‟ descriptions of engagement with real-life dilemmas into a psychoanalytically informed interpretive account of ethical decision-making. Twelve aspirational ethical principles were found to guide participants‟ daily analytic work. Beneficence was the principle most strongly identified with and nonmaleficence was the most neglected ethical principle. Unprocessed countertransference responses were shown to drive earlier prereflective phases of the ethical decision-making process. Mature ethical judgment was predicated upon the retrospective analysis of enactment phenomena. Dissatisfaction was expressed by all participants with regard to the role of professional resources in aiding the resolution of stressful ethical dilemmas. Risk factors for compromised professional decision-making included the paucity and perceived irrelevance of postgraduate ethics training, supervisory failure to confront the ethical and countertransference dimensions of common dilemmas and professional isolation. Rather than eliciting the hope of emotional support and greater insight, professional resources on the contrary mostly appeared to induce anxiety, mistrust and fearfulness. Based on the data and the literature, a pragmatic psychoanalytically informed ethical decision-making model was finally generated. The model, which considers both principle ethics as well as countertransference phenomena, offers a preliminary contribution to professional dialogue on the development and evaluation of empirically based decision-making frameworks. Practical recommendations are made for both the revision of the current South African ethics code and for improving the postqualifying ethics education of psychoanalytic practitioners and supervisors. The limitations of the data are discussed and directions for future research initiatives are proposed.
- Full Text:
- Date Issued: 2009
- Authors: Silove, Melanie
- Date: 2009
- Subjects: Decision making -- Moral and ethical aspects , Psychotherapy -- Moral and ethical aspects , Psychotherapists -- Professional ethics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3273 , http://hdl.handle.net/10962/d1020873
- Description: This study examined the ethical decision-making process as it transpired in the everyday context of the therapeutic space. In-depth interviews explored the subjective experiences of six South African psychologists, practicing as psychoanalytic psychotherapists, and their efforts to resolve real-life ethical dilemmas. The theoretical framework used to interpret the data subsumed professional literature in psychology on principle-based ethical decision-making as well as contemporary psychoanalytic debates on the phenomenon of countertransference enactments. A review of ethics codes, survey research and seminal decision-making frameworks suggests that ethical dilemmas have traditionally been resolved by recourse to an objective and impartial “principle ethics” perspective. Empirical evidence shows, however, that logical thinking and the rational application of codes, principles and standards are often insufficient to secure ethical action. The establishment of reflective space and the core theoretical notion of “ethical decision-making enactments” were proposed in order to address the subjective, irrational and unconscious dimension of professional decision-making. This study used a broadly hermeneutic research method which transformed participants‟ descriptions of engagement with real-life dilemmas into a psychoanalytically informed interpretive account of ethical decision-making. Twelve aspirational ethical principles were found to guide participants‟ daily analytic work. Beneficence was the principle most strongly identified with and nonmaleficence was the most neglected ethical principle. Unprocessed countertransference responses were shown to drive earlier prereflective phases of the ethical decision-making process. Mature ethical judgment was predicated upon the retrospective analysis of enactment phenomena. Dissatisfaction was expressed by all participants with regard to the role of professional resources in aiding the resolution of stressful ethical dilemmas. Risk factors for compromised professional decision-making included the paucity and perceived irrelevance of postgraduate ethics training, supervisory failure to confront the ethical and countertransference dimensions of common dilemmas and professional isolation. Rather than eliciting the hope of emotional support and greater insight, professional resources on the contrary mostly appeared to induce anxiety, mistrust and fearfulness. Based on the data and the literature, a pragmatic psychoanalytically informed ethical decision-making model was finally generated. The model, which considers both principle ethics as well as countertransference phenomena, offers a preliminary contribution to professional dialogue on the development and evaluation of empirically based decision-making frameworks. Practical recommendations are made for both the revision of the current South African ethics code and for improving the postqualifying ethics education of psychoanalytic practitioners and supervisors. The limitations of the data are discussed and directions for future research initiatives are proposed.
- Full Text:
- Date Issued: 2009
Evaluating remuneration and reward systems at lobels bread, Zimbabwe
- Authors: Mtazu, Pauline Sibusisiwe
- Date: 2009
- Subjects: Wages -- Zimbabwe , Compensation management -- Zimbabwe , Performance -- Management , Wages and labor productivity -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8682 , http://hdl.handle.net/10948/1136 , Wages -- Zimbabwe , Compensation management -- Zimbabwe , Performance -- Management , Wages and labor productivity -- Zimbabwe
- Description: To gain workforce support and commitment, organisations should offer remuneration and rewards that are internally and externally equitable, as inequity in remuneration is the source of employee discontent and turnover. To succeed, organisations have to communicate the total value of rewards allocated to employees. Communication is the foundation of reward management and organisational success. Communication helps employees to understand that the rewards they receive are worth having. Remuneration and rewards communicate the value that organisations place on their employees. To deliver the proper messages, remuneration objectives and strategies should be aligned with the overall business strategy of the organisation. Alignment enables organisations to deliver the right type of rewards to the right people, at the right time, and for the right reasons. The only way the organisation can deliver the correct reward and remuneration, is to implement a total reward system together with a total pay system. Effective total pay system covers base pay, skills and competency pay, variable performance pay, recognition, and benefits. Total reward system cover investment in people, development and training, performance management, and career management. To motivate and retain employees, and to improve organisation’s profitability, a right mix of total pay and total rewards should be made available to employees as employees’ needs differ. With this information, an empirical study was developed and conducted at Lobels Bread in Zimbabwe. The results of this survey indicated that Lobels Bread uses traditional base pay system and benefits as a way of motivating and retaining its employees. This pay system seems to be insufficient to motivate and retain employees. To motivate and retain employees, the company should implement a total reward system, which includes total pay system, investment in people, career enhancement, open communications, involvement, and performance management.
- Full Text:
- Date Issued: 2009
- Authors: Mtazu, Pauline Sibusisiwe
- Date: 2009
- Subjects: Wages -- Zimbabwe , Compensation management -- Zimbabwe , Performance -- Management , Wages and labor productivity -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8682 , http://hdl.handle.net/10948/1136 , Wages -- Zimbabwe , Compensation management -- Zimbabwe , Performance -- Management , Wages and labor productivity -- Zimbabwe
- Description: To gain workforce support and commitment, organisations should offer remuneration and rewards that are internally and externally equitable, as inequity in remuneration is the source of employee discontent and turnover. To succeed, organisations have to communicate the total value of rewards allocated to employees. Communication is the foundation of reward management and organisational success. Communication helps employees to understand that the rewards they receive are worth having. Remuneration and rewards communicate the value that organisations place on their employees. To deliver the proper messages, remuneration objectives and strategies should be aligned with the overall business strategy of the organisation. Alignment enables organisations to deliver the right type of rewards to the right people, at the right time, and for the right reasons. The only way the organisation can deliver the correct reward and remuneration, is to implement a total reward system together with a total pay system. Effective total pay system covers base pay, skills and competency pay, variable performance pay, recognition, and benefits. Total reward system cover investment in people, development and training, performance management, and career management. To motivate and retain employees, and to improve organisation’s profitability, a right mix of total pay and total rewards should be made available to employees as employees’ needs differ. With this information, an empirical study was developed and conducted at Lobels Bread in Zimbabwe. The results of this survey indicated that Lobels Bread uses traditional base pay system and benefits as a way of motivating and retaining its employees. This pay system seems to be insufficient to motivate and retain employees. To motivate and retain employees, the company should implement a total reward system, which includes total pay system, investment in people, career enhancement, open communications, involvement, and performance management.
- Full Text:
- Date Issued: 2009
Evaluating text preprocessing to improve compression on maillogs
- Otten, Fred, Irwin, Barry V W, Thinyane, Hannah
- Authors: Otten, Fred , Irwin, Barry V W , Thinyane, Hannah
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430138 , vital:72668 , https://doi.org/10.1145/1632149.1632157
- Description: Maillogs contain important information about mail which has been sent or received. This information can be used for statistical purposes, to help prevent viruses or to help prevent SPAM. In order to satisfy regula-tions and follow good security practices, maillogs need to be monitored and archived. Since there is a large quantity of data, some form of data reduction is necessary. Data compression programs such as gzip and bzip2 are commonly used to reduce the quantity of data. Text preprocessing can be used to aid the compression of English text files. This paper evaluates whether text preprocessing, particularly word replacement, can be used to improve the compression of maillogs. It presents an algorithm for constructing a dictionary for word replacement and provides the results of experiments conducted using the ppmd, gzip, bzip2 and 7zip programs. These tests show that text prepro-cessing improves data compression on maillogs. Improvements of up to 56 percent in compression time and up to 32 percent in compression ratio are achieved. It also shows that a dictionary may be generated and used on other maillogs to yield reductions within half a percent of the results achieved for the maillog used to generate the dictionary.
- Full Text:
- Date Issued: 2009
- Authors: Otten, Fred , Irwin, Barry V W , Thinyane, Hannah
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430138 , vital:72668 , https://doi.org/10.1145/1632149.1632157
- Description: Maillogs contain important information about mail which has been sent or received. This information can be used for statistical purposes, to help prevent viruses or to help prevent SPAM. In order to satisfy regula-tions and follow good security practices, maillogs need to be monitored and archived. Since there is a large quantity of data, some form of data reduction is necessary. Data compression programs such as gzip and bzip2 are commonly used to reduce the quantity of data. Text preprocessing can be used to aid the compression of English text files. This paper evaluates whether text preprocessing, particularly word replacement, can be used to improve the compression of maillogs. It presents an algorithm for constructing a dictionary for word replacement and provides the results of experiments conducted using the ppmd, gzip, bzip2 and 7zip programs. These tests show that text prepro-cessing improves data compression on maillogs. Improvements of up to 56 percent in compression time and up to 32 percent in compression ratio are achieved. It also shows that a dictionary may be generated and used on other maillogs to yield reductions within half a percent of the results achieved for the maillog used to generate the dictionary.
- Full Text:
- Date Issued: 2009
Evaluating the effect of the disability policy on the public and the workers, the case of the Eastern Cape Provincial Legislature during 2007-2008
- Authors: Mbutuma, Pumza
- Date: 2009
- Subjects: People with disabilities -- Legal status, laws, etc. -- South Africa -- Eastern Cape , People with disabilities -- South Africa -- Eastern Cape , People with disabilities -- Government policy , People with disabilities -- Rehabilitation -- South Africa
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: vital:11629 , http://hdl.handle.net/10353/d1001237 , People with disabilities -- Legal status, laws, etc. -- South Africa -- Eastern Cape , People with disabilities -- South Africa -- Eastern Cape , People with disabilities -- Government policy , People with disabilities -- Rehabilitation -- South Africa
- Description: The evaluation of the implementation of disability policies is a result of the low rate of public participation in the Eastern Cape Provincial Legislature’s programs as well as the low number of disabled persons who are employed. Institutions like Parliaments and Legislatures are law making institutions, some of their tasks in to attract comments, suggestions and ideas from all interested parties to participate in the law making process. They also have a responsibility to conduct vigorous oversight over the provincial government departments; this includes issues like compliance with the relevant policies and regulations. The data was collect from three different groupings namely the staff of ECPL, the members of provincial legislature as well as the general public which includes disabled persons. It was clear from the findings that the management and the MPL, who are decision makers of the institution, have a very shallow knowledge of the disability policies and regulations. There is a disability strategy which was made for all the legislatures and National Parliament; however the strategy has not been implemented in ECPL. The institution has to create a special programs unit that will promote equality in line with the Bill of Rights which enshrines the rights of all people in the country and affirms the democratic values of human dignity, equality and freedom. The recommendations that were made included education and awareness programs and compliance with regulations like the Employment Equity Act that seeks to unsure that the employment equity targets are met.
- Full Text:
- Date Issued: 2009
- Authors: Mbutuma, Pumza
- Date: 2009
- Subjects: People with disabilities -- Legal status, laws, etc. -- South Africa -- Eastern Cape , People with disabilities -- South Africa -- Eastern Cape , People with disabilities -- Government policy , People with disabilities -- Rehabilitation -- South Africa
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: vital:11629 , http://hdl.handle.net/10353/d1001237 , People with disabilities -- Legal status, laws, etc. -- South Africa -- Eastern Cape , People with disabilities -- South Africa -- Eastern Cape , People with disabilities -- Government policy , People with disabilities -- Rehabilitation -- South Africa
- Description: The evaluation of the implementation of disability policies is a result of the low rate of public participation in the Eastern Cape Provincial Legislature’s programs as well as the low number of disabled persons who are employed. Institutions like Parliaments and Legislatures are law making institutions, some of their tasks in to attract comments, suggestions and ideas from all interested parties to participate in the law making process. They also have a responsibility to conduct vigorous oversight over the provincial government departments; this includes issues like compliance with the relevant policies and regulations. The data was collect from three different groupings namely the staff of ECPL, the members of provincial legislature as well as the general public which includes disabled persons. It was clear from the findings that the management and the MPL, who are decision makers of the institution, have a very shallow knowledge of the disability policies and regulations. There is a disability strategy which was made for all the legislatures and National Parliament; however the strategy has not been implemented in ECPL. The institution has to create a special programs unit that will promote equality in line with the Bill of Rights which enshrines the rights of all people in the country and affirms the democratic values of human dignity, equality and freedom. The recommendations that were made included education and awareness programs and compliance with regulations like the Employment Equity Act that seeks to unsure that the employment equity targets are met.
- Full Text:
- Date Issued: 2009
Evaluating the IRI topside model for the South African region: An overview of the modelling techniques
- Sibanda, Patrick, McKinnell, Lee-Anne
- Authors: Sibanda, Patrick , McKinnell, Lee-Anne
- Date: 2009
- Language: English
- Type: text , Article
- Identifier: vital:6810 , http://hdl.handle.net/10962/d1004303
- Description: The representation of the topside ionosphere (the region above the F2 peak) is critical because of the limited experimental data available. Over the years, a wide range of models have been developed in an effort to represent the behaviour and the shape of the electron density (Ne) profile of the topside ionosphere. Various studies have been centred around calculating the vertical scale height (VSH) and have included (a) obtaining VSH from Global Positioning System (GPS) derived total electron content (TEC), (b) calculating the VSH from ground-based ionosonde measurements, (c) using topside sounder vertical Ne profiles to obtain the VSH. One or a combination of the topside profilers (Chapman function, exponential function, sech-squared (Epstein) function, and/or parabolic function) is then used to reconstruct the topside Ne profile. The different approaches and the modelling techniques are discussed with a view to identifying the most adequate approach to apply to the South African region’s topside modelling efforts. The IRI-2001 topside model is evaluated based on how well it reproduces measured topside profiles over the South African region. This study is a first step in the process of developing a South African topside ionosphere model.
- Full Text:
- Date Issued: 2009
- Authors: Sibanda, Patrick , McKinnell, Lee-Anne
- Date: 2009
- Language: English
- Type: text , Article
- Identifier: vital:6810 , http://hdl.handle.net/10962/d1004303
- Description: The representation of the topside ionosphere (the region above the F2 peak) is critical because of the limited experimental data available. Over the years, a wide range of models have been developed in an effort to represent the behaviour and the shape of the electron density (Ne) profile of the topside ionosphere. Various studies have been centred around calculating the vertical scale height (VSH) and have included (a) obtaining VSH from Global Positioning System (GPS) derived total electron content (TEC), (b) calculating the VSH from ground-based ionosonde measurements, (c) using topside sounder vertical Ne profiles to obtain the VSH. One or a combination of the topside profilers (Chapman function, exponential function, sech-squared (Epstein) function, and/or parabolic function) is then used to reconstruct the topside Ne profile. The different approaches and the modelling techniques are discussed with a view to identifying the most adequate approach to apply to the South African region’s topside modelling efforts. The IRI-2001 topside model is evaluated based on how well it reproduces measured topside profiles over the South African region. This study is a first step in the process of developing a South African topside ionosphere model.
- Full Text:
- Date Issued: 2009
Evaluating the success of total productive maintenance at Faurecia interior systems
- Faber, John Cornelius Jacobus
- Authors: Faber, John Cornelius Jacobus
- Date: 2009
- Subjects: Total productive maintenance -- South Africa , Total quality management -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8670 , http://hdl.handle.net/10948/1206 , Total productive maintenance -- South Africa , Total quality management -- South Africa
- Description: Manufacturing processes should operate at optimal levels in order to remain competitive in current economic environment. The optimal manufacturing performance can be achieved by overall equipment efficiency which is also a measurement for Total Productive Maintenance (TPM). The successful implementation of TPM has been evaluated at Faurecia Interior Systems. The research consisted out of a literature review into the elements and benefits of TPM. A questionnaire was sent to all operator level personnel at Faurecia Interior Systems to establish their views on the implementation level of TPM at the East London site. In conclusion, this research paper has also led to the development of recommendations which should improve TPM at the site.
- Full Text:
- Date Issued: 2009
- Authors: Faber, John Cornelius Jacobus
- Date: 2009
- Subjects: Total productive maintenance -- South Africa , Total quality management -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8670 , http://hdl.handle.net/10948/1206 , Total productive maintenance -- South Africa , Total quality management -- South Africa
- Description: Manufacturing processes should operate at optimal levels in order to remain competitive in current economic environment. The optimal manufacturing performance can be achieved by overall equipment efficiency which is also a measurement for Total Productive Maintenance (TPM). The successful implementation of TPM has been evaluated at Faurecia Interior Systems. The research consisted out of a literature review into the elements and benefits of TPM. A questionnaire was sent to all operator level personnel at Faurecia Interior Systems to establish their views on the implementation level of TPM at the East London site. In conclusion, this research paper has also led to the development of recommendations which should improve TPM at the site.
- Full Text:
- Date Issued: 2009
Evaluating uncertainty in water resources estimation in Southern Africa : a case study of South Africa
- Authors: Sawunyama, Tendai
- Date: 2009
- Subjects: Water supply -- South Africa , Water supply -- Africa, Southern , Hydrology -- South Africa , Hydrology -- Africa, Southern , Hydrologic models , Hydrology research -- South Africa , Hydrology research -- Africa, Southern , Rain and rainfall -- Mathematical models , Runoff -- Mathematical models
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6035 , http://hdl.handle.net/10962/d1006176
- Description: Hydrological models are widely used tools in water resources estimation, but they are simple representations of reality and are frequently based on inadequate input data and uncertainties in parameter values. Data observation networks are expensive to establish and maintain and often beyond the resources of most developing countries. Consequently, measurements are difficult to obtain and observation networks in many countries are shrinking, hence obtaining representative observations in space and time remains a challenge. This study presents some guidelines on the identification, quantification and reduction of sources of uncertainty in water resources estimation in southern Africa, a data scarce region. The analyses are based on example sub-basins drawn from South Africa and the application of the Pitman hydrological model. While it has always been recognised that estimates of water resources availability for the region are subject to possible errors, the quantification of these uncertainties has never been explicitly incorporated into the methods used in the region. The motivation for this study was therefore to contribute to the future development of a revised framework for water resources estimation that does include uncertainty. The focus was on uncertainties associated with climate input data, parameter estimation (and recognizing the uncertainty due model structure deficiencies) methods and water use data. In addition to variance based measures of uncertainty, this study also used a reservoir yield based statistic to evaluate model output uncertainty, which represents an integrated measure of flow regime variations and one that can be more easily understood by water resources managers. Through a sensitivity analysis approach, the results of the individual contribution of each source of uncertainty suggest regional differences and that clear statements about which source of uncertainty is likely to dominate are not generally possible. Parameter sensitivity analysis was used in identifying parameters which are important withinspecific sub-basins and therefore those to focus on in uncertainty analysis. The study used a simple framework for evaluating the combined contribution of uncertainty sources to model outputs that is consistent with the model limitations and data available, and that allows direct quantitative comparison between model outputs obtained by using different sources of information and methods within Spatial and Time Series Information Modelling (SPATSIM) software. The results from combining the sources of uncertainties showed that parameter uncertainty dominates the contribution to model output uncertainty. However, in some parts of the country especially those with complex topography, which tend to experience high rainfall spatial variability, rainfall uncertainty is equally dominant, while the contributions of evaporation and water use data uncertainty are relatively small. While the results of this study are encouraging, the weaknesses of the methods used to quantify uncertainty (especially subjectivity involved in evaluating parameter uncertainty) should not be neglected and require further evaluations. An effort to reduce data and parameter uncertainty shows that this can only be achieved if data access at appropriate scale and quality improves. Perhaps the focus should be on maintaining existing networks and concentrating research efforts on making the most out of the emerging data products derived from remote sensing platforms. While this study presents some initial guidelines for evaluating uncertainty in South Africa, there is need to overcome several constraints which are related to data availability and accuracy, the models used and the capacity or willingness to adopt new methods that incorporate uncertainty. The study has provided a starting point for the development of new approaches to modelling water resources in the region that include uncertain estimates.
- Full Text:
- Date Issued: 2009
- Authors: Sawunyama, Tendai
- Date: 2009
- Subjects: Water supply -- South Africa , Water supply -- Africa, Southern , Hydrology -- South Africa , Hydrology -- Africa, Southern , Hydrologic models , Hydrology research -- South Africa , Hydrology research -- Africa, Southern , Rain and rainfall -- Mathematical models , Runoff -- Mathematical models
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6035 , http://hdl.handle.net/10962/d1006176
- Description: Hydrological models are widely used tools in water resources estimation, but they are simple representations of reality and are frequently based on inadequate input data and uncertainties in parameter values. Data observation networks are expensive to establish and maintain and often beyond the resources of most developing countries. Consequently, measurements are difficult to obtain and observation networks in many countries are shrinking, hence obtaining representative observations in space and time remains a challenge. This study presents some guidelines on the identification, quantification and reduction of sources of uncertainty in water resources estimation in southern Africa, a data scarce region. The analyses are based on example sub-basins drawn from South Africa and the application of the Pitman hydrological model. While it has always been recognised that estimates of water resources availability for the region are subject to possible errors, the quantification of these uncertainties has never been explicitly incorporated into the methods used in the region. The motivation for this study was therefore to contribute to the future development of a revised framework for water resources estimation that does include uncertainty. The focus was on uncertainties associated with climate input data, parameter estimation (and recognizing the uncertainty due model structure deficiencies) methods and water use data. In addition to variance based measures of uncertainty, this study also used a reservoir yield based statistic to evaluate model output uncertainty, which represents an integrated measure of flow regime variations and one that can be more easily understood by water resources managers. Through a sensitivity analysis approach, the results of the individual contribution of each source of uncertainty suggest regional differences and that clear statements about which source of uncertainty is likely to dominate are not generally possible. Parameter sensitivity analysis was used in identifying parameters which are important withinspecific sub-basins and therefore those to focus on in uncertainty analysis. The study used a simple framework for evaluating the combined contribution of uncertainty sources to model outputs that is consistent with the model limitations and data available, and that allows direct quantitative comparison between model outputs obtained by using different sources of information and methods within Spatial and Time Series Information Modelling (SPATSIM) software. The results from combining the sources of uncertainties showed that parameter uncertainty dominates the contribution to model output uncertainty. However, in some parts of the country especially those with complex topography, which tend to experience high rainfall spatial variability, rainfall uncertainty is equally dominant, while the contributions of evaporation and water use data uncertainty are relatively small. While the results of this study are encouraging, the weaknesses of the methods used to quantify uncertainty (especially subjectivity involved in evaluating parameter uncertainty) should not be neglected and require further evaluations. An effort to reduce data and parameter uncertainty shows that this can only be achieved if data access at appropriate scale and quality improves. Perhaps the focus should be on maintaining existing networks and concentrating research efforts on making the most out of the emerging data products derived from remote sensing platforms. While this study presents some initial guidelines for evaluating uncertainty in South Africa, there is need to overcome several constraints which are related to data availability and accuracy, the models used and the capacity or willingness to adopt new methods that incorporate uncertainty. The study has provided a starting point for the development of new approaches to modelling water resources in the region that include uncertain estimates.
- Full Text:
- Date Issued: 2009
Evaluation of a plant-herbivore system in determining potential efficacy of a candidate biological control agent, cornops aquaticum for water hyacinth, eichhornia crassipes
- Authors: Bownes, Angela
- Date: 2009
- Subjects: Water hyacinth -- Control -- South Africa , Eichhornia crassipedes , Pontederiaceae , Grasshoppers , Biological pest control agents -- South Africa , Weeds -- Biological control -- South Africa , Invasive plants -- Biological control -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5687 , http://hdl.handle.net/10962/d1005373
- Description: Water hyacinth, Eichhornia crassipes Mart. Solms-Laubach (Pontederiaceae), a freefloating aquatic macrophyte of Neotropical origin, was introduced into South Africa as an ornamental aquarium plant in the early 1900’s. By the 1970’s it had reached pest proportions in dams and rivers around the country. Due to the sustainability, cost efficiency and low environmental risk associated with biological control, this has been a widely used method in an attempt to reduce infestations to below the threshold where they cause economic and ecological damage. To date, five arthropod and one pathogen biocontrol agents have been introduced for the control of water hyacinth but their impact has been variable. It is believed that their efficacy is hampered by the presence of highly eutrophic systems in South Africa in which plant growth is prolific and the negative effects of herbivory are therefore mitigated. It is for these reasons that new, potentially more damaging biocontrol agents are being considered for release. The water hyacinth grasshopper, Cornops aquaticum Brüner (Orthoptera: Acrididae), which is native to South America and Mexico, was brought into quarantine in Pretoria, South Africa in 1995. Although the grasshopper was identified as one of the most damaging insects associated with water hyacinth in its native range, it has not been considered as a biocontrol agent for water hyacinth anywhere else in the world. After extensive host-range testing which revealed it to be safe for release, a release permit for this candidate agent was issued in 2007. However, host specificity testing is no longer considered to be the only important component of pre-release screening of candidate biocontrol agents. Investigating biological and ecological aspects of the plant-herbivore system that will assist in determination of potential establishment, efficacy and the ability to build up good populations in the recipient environment are some of the important factors. This thesis is a pre-release evaluation of C. aquaticum to determine whether it is sufficiently damaging to water hyacinth to warrant its release. It investigated interactions between the grasshopper and water hyacinth under a range of nutrient conditions found in South African water bodies as well as the impact of the grasshopper on the competitive performance of water hyacinth. Both plant growth rates and the response of water hyacinth to herbivory by the grasshopper were influenced by nutrient availability to the plants. The ability of water hyacinth to compensate for loss of tissue through herbivory was greater under eutrophic nutrient conditions. However, a negative linear relationship was found between grasshopper biomass and water hyacinth performance parameters such as biomass accumulation and leaf production, even under eutrophic conditions. Water hyacinth’s compensatory ability in terms of its potential to mitigate to detrimental effects of insect feeding was dependent on the amount of damage caused by herbivory by the grasshopper. Plant biomass and the competitive ability of water hyacinth in relation to another freefloating aquatic weed species were reduced by C. aquaticum under eutrophic nutrient conditions, in a short space of time. It was also found that grasshopper feeding and characteristics related to their population dynamics such as fecundity and survival were significantly influenced by water nutrient availability and that environmental nutrient availability will influence the control potential of this species should it be released in South Africa. Cornops aquaticum shows promise as a biocontrol agent for water hyacinth but additional factors that were not investigated in this study such as compatibility with the South African climate and the current water hyacinth biocontrol agents need to be combined with these data to make a decision on its release. Possible management options for this species if it is to be introduced into South Africa are discussed.
- Full Text:
- Date Issued: 2009
- Authors: Bownes, Angela
- Date: 2009
- Subjects: Water hyacinth -- Control -- South Africa , Eichhornia crassipedes , Pontederiaceae , Grasshoppers , Biological pest control agents -- South Africa , Weeds -- Biological control -- South Africa , Invasive plants -- Biological control -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5687 , http://hdl.handle.net/10962/d1005373
- Description: Water hyacinth, Eichhornia crassipes Mart. Solms-Laubach (Pontederiaceae), a freefloating aquatic macrophyte of Neotropical origin, was introduced into South Africa as an ornamental aquarium plant in the early 1900’s. By the 1970’s it had reached pest proportions in dams and rivers around the country. Due to the sustainability, cost efficiency and low environmental risk associated with biological control, this has been a widely used method in an attempt to reduce infestations to below the threshold where they cause economic and ecological damage. To date, five arthropod and one pathogen biocontrol agents have been introduced for the control of water hyacinth but their impact has been variable. It is believed that their efficacy is hampered by the presence of highly eutrophic systems in South Africa in which plant growth is prolific and the negative effects of herbivory are therefore mitigated. It is for these reasons that new, potentially more damaging biocontrol agents are being considered for release. The water hyacinth grasshopper, Cornops aquaticum Brüner (Orthoptera: Acrididae), which is native to South America and Mexico, was brought into quarantine in Pretoria, South Africa in 1995. Although the grasshopper was identified as one of the most damaging insects associated with water hyacinth in its native range, it has not been considered as a biocontrol agent for water hyacinth anywhere else in the world. After extensive host-range testing which revealed it to be safe for release, a release permit for this candidate agent was issued in 2007. However, host specificity testing is no longer considered to be the only important component of pre-release screening of candidate biocontrol agents. Investigating biological and ecological aspects of the plant-herbivore system that will assist in determination of potential establishment, efficacy and the ability to build up good populations in the recipient environment are some of the important factors. This thesis is a pre-release evaluation of C. aquaticum to determine whether it is sufficiently damaging to water hyacinth to warrant its release. It investigated interactions between the grasshopper and water hyacinth under a range of nutrient conditions found in South African water bodies as well as the impact of the grasshopper on the competitive performance of water hyacinth. Both plant growth rates and the response of water hyacinth to herbivory by the grasshopper were influenced by nutrient availability to the plants. The ability of water hyacinth to compensate for loss of tissue through herbivory was greater under eutrophic nutrient conditions. However, a negative linear relationship was found between grasshopper biomass and water hyacinth performance parameters such as biomass accumulation and leaf production, even under eutrophic conditions. Water hyacinth’s compensatory ability in terms of its potential to mitigate to detrimental effects of insect feeding was dependent on the amount of damage caused by herbivory by the grasshopper. Plant biomass and the competitive ability of water hyacinth in relation to another freefloating aquatic weed species were reduced by C. aquaticum under eutrophic nutrient conditions, in a short space of time. It was also found that grasshopper feeding and characteristics related to their population dynamics such as fecundity and survival were significantly influenced by water nutrient availability and that environmental nutrient availability will influence the control potential of this species should it be released in South Africa. Cornops aquaticum shows promise as a biocontrol agent for water hyacinth but additional factors that were not investigated in this study such as compatibility with the South African climate and the current water hyacinth biocontrol agents need to be combined with these data to make a decision on its release. Possible management options for this species if it is to be introduced into South Africa are discussed.
- Full Text:
- Date Issued: 2009
Evaluation of an implemented quality management system (QMS) at one of the South African government departments: employee perceptions of the effect of the QMS intervention
- Authors: Maluleke, Yinywane Leon
- Date: 2009
- Subjects: Total quality management in government Public administration -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:739 , http://hdl.handle.net/10962/d1003859
- Description: This study is about the employee perceptions of the effect of the Quality Management System intervention that was implemented at one of South Africa’s government departments. This organisation’s Quality Management System being one of the first in the government or public sector in South Africa to be implemented, creates the possibility for this Quality Management System model to be used to develop Quality Management Systems in other departments or organisations belonging to the government or the public sector in South Africa and the Southern African region. According to Madu & Kuei (1995), Quality Management System describes a situation where all business functions are involved in a process of continuous quality improvement. This implies that the development and implementation of Quality Management Systems in government departments and the public sector will improve the quality of services delivery. The findings of this study indicated that a Quality Management System can be used to improve the level of service delivery in the public sector. The Quality Management System should be planned developed and implemented over a period of time in five phases (i) Phase 1 - Determination of the scope of Quality Management System implementation (ii) Phase 2 – Training (iii) Phase 3 – Development of Procedures (iv) Phase 4 – Pilot implementation of procedures (v) Phase 5 – Evaluation of Quality Management System and rollout. It usually takes three or more years to establish an organisation-wide Quality Management System, although technical improvement to the workflow can be as quickly as six to eight months. And finally, for the Quality Management System to be developed, implemented and maintained successfully, Maximisation of Performance objectives, Good Leadership, Motivation of staff, Implementation of Change Management, Employee Involvement, Long-term Top Management Commitment, Provision of Training, Introduction of Quality Improvement Projects, Measuring Quality Management System Progress and Reward Accomplishment, are the fundamental concepts or principles that should be considered.
- Full Text:
- Date Issued: 2009
- Authors: Maluleke, Yinywane Leon
- Date: 2009
- Subjects: Total quality management in government Public administration -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:739 , http://hdl.handle.net/10962/d1003859
- Description: This study is about the employee perceptions of the effect of the Quality Management System intervention that was implemented at one of South Africa’s government departments. This organisation’s Quality Management System being one of the first in the government or public sector in South Africa to be implemented, creates the possibility for this Quality Management System model to be used to develop Quality Management Systems in other departments or organisations belonging to the government or the public sector in South Africa and the Southern African region. According to Madu & Kuei (1995), Quality Management System describes a situation where all business functions are involved in a process of continuous quality improvement. This implies that the development and implementation of Quality Management Systems in government departments and the public sector will improve the quality of services delivery. The findings of this study indicated that a Quality Management System can be used to improve the level of service delivery in the public sector. The Quality Management System should be planned developed and implemented over a period of time in five phases (i) Phase 1 - Determination of the scope of Quality Management System implementation (ii) Phase 2 – Training (iii) Phase 3 – Development of Procedures (iv) Phase 4 – Pilot implementation of procedures (v) Phase 5 – Evaluation of Quality Management System and rollout. It usually takes three or more years to establish an organisation-wide Quality Management System, although technical improvement to the workflow can be as quickly as six to eight months. And finally, for the Quality Management System to be developed, implemented and maintained successfully, Maximisation of Performance objectives, Good Leadership, Motivation of staff, Implementation of Change Management, Employee Involvement, Long-term Top Management Commitment, Provision of Training, Introduction of Quality Improvement Projects, Measuring Quality Management System Progress and Reward Accomplishment, are the fundamental concepts or principles that should be considered.
- Full Text:
- Date Issued: 2009
Evaluation of the effect of Pelargonium reniforme Curtis extract on alcohol induced liver damage in Nkonkobe Municipality Eastern Cape Province South Africa
- Authors: Adewusi, Emmanuel Adekanmi
- Date: 2009
- Subjects: Plants -- Therapeutic use , Alcoholism -- South Africa -- Eastern Cape , Hepatolenticular degeneration , Pelargoniums , Plant extracts , Plant bioassay , Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Ethnobotany)
- Identifier: vital:11883 , http://hdl.handle.net/10353/263 , Plants -- Therapeutic use , Alcoholism -- South Africa -- Eastern Cape , Hepatolenticular degeneration , Pelargoniums , Plant extracts , Plant bioassay , Medicinal plants -- South Africa -- Eastern Cape
- Description: Alcohol abuse is a very common practice (just like in many other parts of the world) in Nkonkobe Municipality, Eastern Cape Province, South Africa. This is associated with liver disease. An ethnobotanical survey of plants used for the treatment of alcohol-induced liver damage in Nkonkobe Municipality was conducted. During the survey and also from information gathered in the literature, Pelargonium reniforme Curtis, was prominently mentioned, among other plants, as the species used generally for the treatment of alcohol-induced liver damage. This project was designed to evaluate the effects of the plant on alcohol-induced liver damage, including its antioxidant and antimicrobial properties. It also involves safety evaluation studies to determine if the plant is safe for consumption. Studies using rats of the Wistar strain were carried out to determine the protective and curative effects of P. reniforme on alcohol-induced liver damage. Results obtained showed that the plant extract can protect the liver cells as well as enhance recovery from tissue damage. The plant also showed good antimicrobial and antioxidant activity and this further validates its use in the treatment of liver diseases. Safety evaluation studies of the extract were carried out by investigating the effects of the oral administration on some haematological and biochemical parameters in male Wistar rats. The results obtained from the study suggest that the plant extract is not toxic at the doses used and is therefore safe for medicinal uses. The results of the various bioassays carried out in this project have justified the traditional uses of P. reniforme for the treatment of alcohol-induced liver damage.
- Full Text:
- Date Issued: 2009
- Authors: Adewusi, Emmanuel Adekanmi
- Date: 2009
- Subjects: Plants -- Therapeutic use , Alcoholism -- South Africa -- Eastern Cape , Hepatolenticular degeneration , Pelargoniums , Plant extracts , Plant bioassay , Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Ethnobotany)
- Identifier: vital:11883 , http://hdl.handle.net/10353/263 , Plants -- Therapeutic use , Alcoholism -- South Africa -- Eastern Cape , Hepatolenticular degeneration , Pelargoniums , Plant extracts , Plant bioassay , Medicinal plants -- South Africa -- Eastern Cape
- Description: Alcohol abuse is a very common practice (just like in many other parts of the world) in Nkonkobe Municipality, Eastern Cape Province, South Africa. This is associated with liver disease. An ethnobotanical survey of plants used for the treatment of alcohol-induced liver damage in Nkonkobe Municipality was conducted. During the survey and also from information gathered in the literature, Pelargonium reniforme Curtis, was prominently mentioned, among other plants, as the species used generally for the treatment of alcohol-induced liver damage. This project was designed to evaluate the effects of the plant on alcohol-induced liver damage, including its antioxidant and antimicrobial properties. It also involves safety evaluation studies to determine if the plant is safe for consumption. Studies using rats of the Wistar strain were carried out to determine the protective and curative effects of P. reniforme on alcohol-induced liver damage. Results obtained showed that the plant extract can protect the liver cells as well as enhance recovery from tissue damage. The plant also showed good antimicrobial and antioxidant activity and this further validates its use in the treatment of liver diseases. Safety evaluation studies of the extract were carried out by investigating the effects of the oral administration on some haematological and biochemical parameters in male Wistar rats. The results obtained from the study suggest that the plant extract is not toxic at the doses used and is therefore safe for medicinal uses. The results of the various bioassays carried out in this project have justified the traditional uses of P. reniforme for the treatment of alcohol-induced liver damage.
- Full Text:
- Date Issued: 2009
Evolutionary development and functional role of plant natriuretic peptide (PNP)-B
- Authors: Hove, Runyararo Memory
- Date: 2009
- Subjects: Plant hormones , Peptides , Plant gene expression , Peptide hormones , Peptides -- Separation
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11251 , http://hdl.handle.net/10353/155 , Plant hormones , Peptides , Plant gene expression , Peptide hormones , Peptides -- Separation
- Description: Plant natriuretic peptides (PNP) are novel peptides which, like in vertebrates, have been shown to have a function associated with water and salt homeostasis. Two PNP-encoding genes have been identified and isolated from Arabidopsis thaliana, namely; AtPNP-A and AtPNP-B. In this study, the focus was on PNP-B, which has not been extensively studied. Bioinformatic analysis was done on the AtPNP-B gene. This included the bioinformatic study of its primary structure, secondary structure, tertiary structure, transcription factor binding sites (TFBS) and its relation to other known proteins. The AtPNP-B gene was shown to be a 510 bp long, including a predicted 138 bp intron. AtPNP-B was also shown to have some sequence similarity with AtPNP-A and CjBAp12. The TFBS for AtPNP-B and OsJPNP-B were compared and they comprised of TFBS that are related to water homeostasis and pathogenesis. This suggested two possible functions; water stress and homeostasis and a pathogenesis related function for PNP-B. Following bioinformatic analysis, the heterologous expression of the AtPNP-B was attempted to investigate whether the AtPNP-B gene encoded a functional protein and to determine the functional role of PNP-B. However, expression was unsuccessful. An evolutionary study was then carried out which revealed that there were some plants without the intron such as, rice, leafy spurge, oilseed rape, onion, poplar, sugar cane, sunflower and tobacco. These plants would therefore be used for expression and functional studies in the future. The evolutionary studies also revealed that PNP-B had a relationship with expansins and the endoglucanase family 45. Other PNP-B related molecules were also obtained from other plant genomes and therefore used in the construction of a phylogenetic tree. The phylogenetic tree revealed that AtPNP-B clustered in the same group as CjBAp12 while AtPNP-A had its own cluster group. There were also other PNP-B like molecules that clustered in the same group as expansins (α- and β-). Thus, we postulate that, like PNP-A, PNP-B also has a possible function in water and salt homeostasis. However, due to the clustering iii of AtPNP-B into the same group as CjBAp12, a possible role of PNP-B in pathogenesis-related response is also postulated.
- Full Text:
- Date Issued: 2009
- Authors: Hove, Runyararo Memory
- Date: 2009
- Subjects: Plant hormones , Peptides , Plant gene expression , Peptide hormones , Peptides -- Separation
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11251 , http://hdl.handle.net/10353/155 , Plant hormones , Peptides , Plant gene expression , Peptide hormones , Peptides -- Separation
- Description: Plant natriuretic peptides (PNP) are novel peptides which, like in vertebrates, have been shown to have a function associated with water and salt homeostasis. Two PNP-encoding genes have been identified and isolated from Arabidopsis thaliana, namely; AtPNP-A and AtPNP-B. In this study, the focus was on PNP-B, which has not been extensively studied. Bioinformatic analysis was done on the AtPNP-B gene. This included the bioinformatic study of its primary structure, secondary structure, tertiary structure, transcription factor binding sites (TFBS) and its relation to other known proteins. The AtPNP-B gene was shown to be a 510 bp long, including a predicted 138 bp intron. AtPNP-B was also shown to have some sequence similarity with AtPNP-A and CjBAp12. The TFBS for AtPNP-B and OsJPNP-B were compared and they comprised of TFBS that are related to water homeostasis and pathogenesis. This suggested two possible functions; water stress and homeostasis and a pathogenesis related function for PNP-B. Following bioinformatic analysis, the heterologous expression of the AtPNP-B was attempted to investigate whether the AtPNP-B gene encoded a functional protein and to determine the functional role of PNP-B. However, expression was unsuccessful. An evolutionary study was then carried out which revealed that there were some plants without the intron such as, rice, leafy spurge, oilseed rape, onion, poplar, sugar cane, sunflower and tobacco. These plants would therefore be used for expression and functional studies in the future. The evolutionary studies also revealed that PNP-B had a relationship with expansins and the endoglucanase family 45. Other PNP-B related molecules were also obtained from other plant genomes and therefore used in the construction of a phylogenetic tree. The phylogenetic tree revealed that AtPNP-B clustered in the same group as CjBAp12 while AtPNP-A had its own cluster group. There were also other PNP-B like molecules that clustered in the same group as expansins (α- and β-). Thus, we postulate that, like PNP-A, PNP-B also has a possible function in water and salt homeostasis. However, due to the clustering iii of AtPNP-B into the same group as CjBAp12, a possible role of PNP-B in pathogenesis-related response is also postulated.
- Full Text:
- Date Issued: 2009
Exchange rate pass‐through to import prices in South Africa: is there asymmetry?
- Karoro, Tapiwa D, Aziakpono, Meshach J, Cattaneo, Nicolette S
- Authors: Karoro, Tapiwa D , Aziakpono, Meshach J , Cattaneo, Nicolette S
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/469753 , vital:77291 , https://doi.org/10.1111/j.1813-6982.2009.01216.x
- Description: This paper examines the magnitude and speed of exchange rate pass‐through (ERPT) to import prices in South Africa. It further explores whether the direction and size of changes in the exchange rate have different pass‐through effects on import prices, i.e. whether the exchange rate pass‐through is symmetric or asymmetric. The findings of the study suggest that ERPT in South Africa is incomplete but relatively high. Furthermore, ERPT is found to be higher in periods of rand depreciation than appreciation, which supports the binding quantity constraint theory. There is also evidence to suggest that pass‐through is slightly higher in periods of small changes than large changes in the exchange rate in harmony with the menu cost theory when the invoices are denominated in the exporters' currency.
- Full Text:
- Date Issued: 2009
- Authors: Karoro, Tapiwa D , Aziakpono, Meshach J , Cattaneo, Nicolette S
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/469753 , vital:77291 , https://doi.org/10.1111/j.1813-6982.2009.01216.x
- Description: This paper examines the magnitude and speed of exchange rate pass‐through (ERPT) to import prices in South Africa. It further explores whether the direction and size of changes in the exchange rate have different pass‐through effects on import prices, i.e. whether the exchange rate pass‐through is symmetric or asymmetric. The findings of the study suggest that ERPT in South Africa is incomplete but relatively high. Furthermore, ERPT is found to be higher in periods of rand depreciation than appreciation, which supports the binding quantity constraint theory. There is also evidence to suggest that pass‐through is slightly higher in periods of small changes than large changes in the exchange rate in harmony with the menu cost theory when the invoices are denominated in the exporters' currency.
- Full Text:
- Date Issued: 2009