Investigations of the bioavailability/bioequivalence of topical corticosteroid formulations containing clobetasol propionate using the human skin blanching assay, tape stripping and microdialysis
- Authors: Au, Wai Ling
- Date: 2010
- Subjects: Adrenocortical hormones -- Bioavailability , Drugs -- Therapeutic equivalency , Adrenocortical hormones -- Effectiveness , Adrenocortical hormones -- Testing , Adrenocortical hormones -- Side effects , Transdermal medication
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3743 , http://hdl.handle.net/10962/d1003221 , Adrenocortical hormones -- Bioavailability , Drugs -- Therapeutic equivalency , Adrenocortical hormones -- Effectiveness , Adrenocortical hormones -- Testing , Adrenocortical hormones -- Side effects , Transdermal medication
- Description: Currently, clinical trials in patients are required by most regulatory authorities for the assessment of bioequivalence of topical products where the drug is not intended for systemic absorption. Hence there is a dire need for suitable methods for the assessment of bioavailability and bioequivalence of such products since clinical safety and efficacy studies are expensive, time-consuming and require very large numbers of patients. Except for topical corticosteroid products where the human skin blanching assay/vasoconstrictor assay has been approved by the US FDA for bioequivalence assessment of those products, no other method has been “officially” approved for use in those investigations. However, a few alternative methods such as tape stripping and microdialysis have been pursued and considered to have the potential for use in ioequivalence/bioavailability studies. The human skin blanching assay was used to assess the bioequivalence of commercially available topical products containing 0.05% clobetasol propionate. Both visual and chromameter data were obtained and a commercially available topical corticosteroid product, Dermovate® cream was used as both the “Test” and the “Reference” product. The results indicated that both visual and chromametric assessments were comparable to each other and that either could be used for the assessment of the bioequivalence of topical products containing clobetasol propionate. The screening procedure was optimized to identify potential “detectors” for inclusion in the bioequivalence studies. This resulted in fewer subjects being required in a bioequivalence pivotal study, still having the necessary power to confirm bioequivalence using the human skin blanching assay. Another objective of this research was to re-visit tape stripping and other possible alternative methods such as dermal microdialysis and to optimize these procedures for bioequivalence assessment of topical formulations where the drug is not intended for systemic absorption. In the past few decades, tape stripping has been used to investigate bioavailability/bioequivalence of various topical formulations. This technique involves the removal of the stratum corneum to assess drug penetration through the skin. A draft FDA guidance for tape stripping was initially published but was subsequently withdrawn due to high variability and poor reproducibility. This research project used an optimized tape stripping procedure to determine bioavailability and establish bioequivalence between three commercially available formulations containing 0.05 % m/m clobetasol propionate. Furthermore, tape stripping was validated by undertaking a study to assess the bioequivalence of a 0.05% topical cream formulation (Dermovate® cream) using the same cream as both the “Test” and “Reference” product, in which bioequivalence was confirmed. The findings highlight the potential of tape stripping as an alternative method for the assessment of bioequivalence of clobetasol propionate formulations and may possibly be extended for use in other topical products. Microdialysis is another useful technique that can assess the penetration of topically applied substances which diffuses through the stratum corneum and into the dermis. Microdialysis has previously been successfully used for in vivo bioavailability and bioequivalence assessments of topical formulations. However, the drugs which were under investigation were all hydrophilic in nature. A major problem with the use of microdialysis for the assessment of lipophilic substances is the binding/adherence of the substance to the membrane and other components of the microdialysis system. As a result, this necessitates the development of a microdialysis system which can be used to assess lipophilic drugs. Intralipid® 20% was investigated and successfully utilized as a perfusate to recover a lipophilic topical corticosteroid, clobetasol propionate, in microdialysis studies. Hence, the bioavailability of clobetasol propionate from an extemporaneous preparation was determined in healthy human volunteers using microdialysis. These findings indicate that in vivo microdialysis can be used to assess lipophilic drug penetration through the skin. A novel approach to investigate drug release from topical formulations containing 0.05% clobetasol propionate using in vitro microdialysis was also undertaken. The in vitro findings were found to be in agreement with the results obtained using tape stripping to assess bioequivalence of the same commercially available products, namely Dermovate® cream, Dovate® Cream and Dermovate® ointment. These results indicate the potential to correlate in vitro with in vivo data for bioequivalence assessment of such topical dosage forms.
- Full Text:
- Date Issued: 2010
- Authors: Au, Wai Ling
- Date: 2010
- Subjects: Adrenocortical hormones -- Bioavailability , Drugs -- Therapeutic equivalency , Adrenocortical hormones -- Effectiveness , Adrenocortical hormones -- Testing , Adrenocortical hormones -- Side effects , Transdermal medication
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3743 , http://hdl.handle.net/10962/d1003221 , Adrenocortical hormones -- Bioavailability , Drugs -- Therapeutic equivalency , Adrenocortical hormones -- Effectiveness , Adrenocortical hormones -- Testing , Adrenocortical hormones -- Side effects , Transdermal medication
- Description: Currently, clinical trials in patients are required by most regulatory authorities for the assessment of bioequivalence of topical products where the drug is not intended for systemic absorption. Hence there is a dire need for suitable methods for the assessment of bioavailability and bioequivalence of such products since clinical safety and efficacy studies are expensive, time-consuming and require very large numbers of patients. Except for topical corticosteroid products where the human skin blanching assay/vasoconstrictor assay has been approved by the US FDA for bioequivalence assessment of those products, no other method has been “officially” approved for use in those investigations. However, a few alternative methods such as tape stripping and microdialysis have been pursued and considered to have the potential for use in ioequivalence/bioavailability studies. The human skin blanching assay was used to assess the bioequivalence of commercially available topical products containing 0.05% clobetasol propionate. Both visual and chromameter data were obtained and a commercially available topical corticosteroid product, Dermovate® cream was used as both the “Test” and the “Reference” product. The results indicated that both visual and chromametric assessments were comparable to each other and that either could be used for the assessment of the bioequivalence of topical products containing clobetasol propionate. The screening procedure was optimized to identify potential “detectors” for inclusion in the bioequivalence studies. This resulted in fewer subjects being required in a bioequivalence pivotal study, still having the necessary power to confirm bioequivalence using the human skin blanching assay. Another objective of this research was to re-visit tape stripping and other possible alternative methods such as dermal microdialysis and to optimize these procedures for bioequivalence assessment of topical formulations where the drug is not intended for systemic absorption. In the past few decades, tape stripping has been used to investigate bioavailability/bioequivalence of various topical formulations. This technique involves the removal of the stratum corneum to assess drug penetration through the skin. A draft FDA guidance for tape stripping was initially published but was subsequently withdrawn due to high variability and poor reproducibility. This research project used an optimized tape stripping procedure to determine bioavailability and establish bioequivalence between three commercially available formulations containing 0.05 % m/m clobetasol propionate. Furthermore, tape stripping was validated by undertaking a study to assess the bioequivalence of a 0.05% topical cream formulation (Dermovate® cream) using the same cream as both the “Test” and “Reference” product, in which bioequivalence was confirmed. The findings highlight the potential of tape stripping as an alternative method for the assessment of bioequivalence of clobetasol propionate formulations and may possibly be extended for use in other topical products. Microdialysis is another useful technique that can assess the penetration of topically applied substances which diffuses through the stratum corneum and into the dermis. Microdialysis has previously been successfully used for in vivo bioavailability and bioequivalence assessments of topical formulations. However, the drugs which were under investigation were all hydrophilic in nature. A major problem with the use of microdialysis for the assessment of lipophilic substances is the binding/adherence of the substance to the membrane and other components of the microdialysis system. As a result, this necessitates the development of a microdialysis system which can be used to assess lipophilic drugs. Intralipid® 20% was investigated and successfully utilized as a perfusate to recover a lipophilic topical corticosteroid, clobetasol propionate, in microdialysis studies. Hence, the bioavailability of clobetasol propionate from an extemporaneous preparation was determined in healthy human volunteers using microdialysis. These findings indicate that in vivo microdialysis can be used to assess lipophilic drug penetration through the skin. A novel approach to investigate drug release from topical formulations containing 0.05% clobetasol propionate using in vitro microdialysis was also undertaken. The in vitro findings were found to be in agreement with the results obtained using tape stripping to assess bioequivalence of the same commercially available products, namely Dermovate® cream, Dovate® Cream and Dermovate® ointment. These results indicate the potential to correlate in vitro with in vivo data for bioequivalence assessment of such topical dosage forms.
- Full Text:
- Date Issued: 2010
Residents’ perspectives on township tourism in Mondesa, Swakopmund, Namibia
- Auala, Lovisa Sisco Ndapanda
- Authors: Auala, Lovisa Sisco Ndapanda
- Date: 2019
- Subjects: Tourism — Namibia
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/42448 , vital:36661
- Description: Township tourism is regarded as one of the fastest growing tourist activities in Namibia (Buning, Legant, Schauwinhold, Steinbrink & Subenguth, 2016:14). This research study presents an exploratory inquiry that seeks an in-depth understanding of residents’perspectives on township tourism in Mondesa, Swakopmund, Namibia.In order to conceptualise the extent to which the residents’needs are being met through the benefits derived from township tourism. The residents’ perspectives on township tourism in Mondesa areexplored with respect to the benefits and costs derived from township tourism, participation in township tourism, and interaction with tourist during a township tour and consultation on township tourismwhich forms part of the research questions ofthe study. By applying the Social Exchange Theory (SET) in this study, the relationships between the variables that influence the residents perceived benefit and costs of township tourism in Mondesa are explored further in depth in combination with Pretty’s Typology of participation and Scheyne’s typology of community empowerment in tourism (Ap, 1992: 668; Mason, 2003:119; Sharpley and Telfer, 2002:152;Cooper, Fletcher, Gilbert & Wanhill, 1993:91).These variables are namely; social, economic, psychological, environmental, cultural, Manipulative, passive, educational and political factors. They form part of the conceptual framework of the study.This study followed a qualitative research approachandmultiple data sources were collected including semi-structured interviews with residents from Mondesa:these included residents involved in township tourism and those not involved in township tourism. To triangulate the data collection, semi-structured interviews were conducted with representatives from tourism industry and government bodies related to townshiptourism. Data analysis was done through the facilitation of Atlas tiaqualitative data analysis software and deductive codes were established from the literature(variables from the conceptual framework)and themes were developed from the research questions.The findings indicate that residents who are not involved in township tourism arenot influenced by the benefit and cost equation of the social exchange theory (Andriotis, 2005:69). Therefore residents not involved in township tourism are positive about tourism irrespective of whether they benefit directly from financial gain through tourism. The findingsfurtheremphasis oncommunity benefitsfrom township tourism being as important, than individual benefits. This study also provides knowledge that meaningful interaction between tourist and residents has the ability to reduce the apartheid paradigm of racial division and discrimination, which was the basis of the formation of townships.Residents’ misconception about white people are changed due to their personal interaction and cultural exchange with white tourist during a township tour. Anothersignificant findings to emerge from this study is the ability for township tourism to transform the lives of residents living in townships through the intrinsic benefits derived from township tourism. Township tourism has the ability to contribute to positive human exchange through interaction between residents and tourists. By sharing a positive cultural exchange, strong relationships are built between the tourists and residents, which may provide long term sustainability of township tourism. The positive personal transformational effect on residents through interaction with tourists is contributing to residents’ socio-economic well-being. Therefore township tourism has the ability to quantitatively and qualitatively address the alleviationof poverty in townshipsand fostering understanding and mutual respect among peoples of the world.The studyconcluded with a framework of guidelines toaid key stakeholders in the development and planning of township tourism and encourages the practice of sustainable tourism in townships.
- Full Text:
- Date Issued: 2019
- Authors: Auala, Lovisa Sisco Ndapanda
- Date: 2019
- Subjects: Tourism — Namibia
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/42448 , vital:36661
- Description: Township tourism is regarded as one of the fastest growing tourist activities in Namibia (Buning, Legant, Schauwinhold, Steinbrink & Subenguth, 2016:14). This research study presents an exploratory inquiry that seeks an in-depth understanding of residents’perspectives on township tourism in Mondesa, Swakopmund, Namibia.In order to conceptualise the extent to which the residents’needs are being met through the benefits derived from township tourism. The residents’ perspectives on township tourism in Mondesa areexplored with respect to the benefits and costs derived from township tourism, participation in township tourism, and interaction with tourist during a township tour and consultation on township tourismwhich forms part of the research questions ofthe study. By applying the Social Exchange Theory (SET) in this study, the relationships between the variables that influence the residents perceived benefit and costs of township tourism in Mondesa are explored further in depth in combination with Pretty’s Typology of participation and Scheyne’s typology of community empowerment in tourism (Ap, 1992: 668; Mason, 2003:119; Sharpley and Telfer, 2002:152;Cooper, Fletcher, Gilbert & Wanhill, 1993:91).These variables are namely; social, economic, psychological, environmental, cultural, Manipulative, passive, educational and political factors. They form part of the conceptual framework of the study.This study followed a qualitative research approachandmultiple data sources were collected including semi-structured interviews with residents from Mondesa:these included residents involved in township tourism and those not involved in township tourism. To triangulate the data collection, semi-structured interviews were conducted with representatives from tourism industry and government bodies related to townshiptourism. Data analysis was done through the facilitation of Atlas tiaqualitative data analysis software and deductive codes were established from the literature(variables from the conceptual framework)and themes were developed from the research questions.The findings indicate that residents who are not involved in township tourism arenot influenced by the benefit and cost equation of the social exchange theory (Andriotis, 2005:69). Therefore residents not involved in township tourism are positive about tourism irrespective of whether they benefit directly from financial gain through tourism. The findingsfurtheremphasis oncommunity benefitsfrom township tourism being as important, than individual benefits. This study also provides knowledge that meaningful interaction between tourist and residents has the ability to reduce the apartheid paradigm of racial division and discrimination, which was the basis of the formation of townships.Residents’ misconception about white people are changed due to their personal interaction and cultural exchange with white tourist during a township tour. Anothersignificant findings to emerge from this study is the ability for township tourism to transform the lives of residents living in townships through the intrinsic benefits derived from township tourism. Township tourism has the ability to contribute to positive human exchange through interaction between residents and tourists. By sharing a positive cultural exchange, strong relationships are built between the tourists and residents, which may provide long term sustainability of township tourism. The positive personal transformational effect on residents through interaction with tourists is contributing to residents’ socio-economic well-being. Therefore township tourism has the ability to quantitatively and qualitatively address the alleviationof poverty in townshipsand fostering understanding and mutual respect among peoples of the world.The studyconcluded with a framework of guidelines toaid key stakeholders in the development and planning of township tourism and encourages the practice of sustainable tourism in townships.
- Full Text:
- Date Issued: 2019
Socio-ecological, contextual effects in Raven’s Colour Progressive Matrices scores: Developing an index for guiding test selection and interpretation
- Authors: August, Justin Oswin
- Date: 2020
- Subjects: Ecological Systems Theory
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/46401 , vital:39563
- Description: With the changing landscape in South Africa to a full democracy, increased research has been undertaken in the psychometric field on local and national normative studies regarding various assessment measures. Given that the Raven’s Coloured Progressive Matrices (CPM)is purported to be culture-free and not heavily dependent on verbal and language skills;it has been extensively normed throughout the world for various population groups. While norms for normal populations of children have been developed in South Africa, these studies were based on race and gender predominantly and without taking into consideration the effects of socio-ecological factors on test performance. The research study aimed to understand the influence of socio-ecological factors on the expression of cognitive scores amongst a geographically diverse sample of South African learners. Through this study, research on the interplay between context and cognition was to be located within the Ecological Systems model of Bronfenbrenner. A secondary aim of the study was to develop an index that will guide test selection and interpretation of assessment results, taking into account the influence of socio-ecological factors and providing a conceptual framework for future test development. The study employed a quantitative methodology on a South African sample consisting of primary school children aged between the ages of 6 years to 11 years. The sample was drawn from schools in the Port Elizabeth areain South Africa that wereclassified into low, medium and high opportunity, based on context. The results indicated that the type of school had a significant impact on test performance, suggesting that contextual factors were influential in this process.The item analysisconductedfurther indicated that learners from a low opportunity school performed significantly lower than the other two schoolsin the sample. The index development provides a foundation for further research that would enhance the interpretation of test results. In the South African context, this is considered important, given our political history and our diversity wherea“one size fits all” approach is not possible.
- Full Text:
- Date Issued: 2020
- Authors: August, Justin Oswin
- Date: 2020
- Subjects: Ecological Systems Theory
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/46401 , vital:39563
- Description: With the changing landscape in South Africa to a full democracy, increased research has been undertaken in the psychometric field on local and national normative studies regarding various assessment measures. Given that the Raven’s Coloured Progressive Matrices (CPM)is purported to be culture-free and not heavily dependent on verbal and language skills;it has been extensively normed throughout the world for various population groups. While norms for normal populations of children have been developed in South Africa, these studies were based on race and gender predominantly and without taking into consideration the effects of socio-ecological factors on test performance. The research study aimed to understand the influence of socio-ecological factors on the expression of cognitive scores amongst a geographically diverse sample of South African learners. Through this study, research on the interplay between context and cognition was to be located within the Ecological Systems model of Bronfenbrenner. A secondary aim of the study was to develop an index that will guide test selection and interpretation of assessment results, taking into account the influence of socio-ecological factors and providing a conceptual framework for future test development. The study employed a quantitative methodology on a South African sample consisting of primary school children aged between the ages of 6 years to 11 years. The sample was drawn from schools in the Port Elizabeth areain South Africa that wereclassified into low, medium and high opportunity, based on context. The results indicated that the type of school had a significant impact on test performance, suggesting that contextual factors were influential in this process.The item analysisconductedfurther indicated that learners from a low opportunity school performed significantly lower than the other two schoolsin the sample. The index development provides a foundation for further research that would enhance the interpretation of test results. In the South African context, this is considered important, given our political history and our diversity wherea“one size fits all” approach is not possible.
- Full Text:
- Date Issued: 2020
Socio-ecological, contextual effects in Raven’s Colour Progressive Matrices scores: developing an index for guiding test selection and interpretation
- Authors: August, Justin Oswin
- Date: 2019
- Subjects: Psychological testing
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50214 , vital:42071
- Description: With the changing landscape in South Africa to full democracy, increased research has been undertaken in the psychometric field on local and national normative studies regarding various assessment measures. Given that the Raven’s Coloured Progressive Matrices (CPM) is purported to be culture-free and not heavily dependent on verbal and language skills; it has been extensively normed throughout the world for various population groups. While norms for normal populations of children have been developed in South Africa, these studies were based on race and gender predominantly and without taking into consideration the effects of socio-ecological factors on test performance. The research study aimed to understand the influence of socio-ecological factors on the expression of cognitive scores amongst a geographically diverse sample of South African learners. Through this study, research on the interplay between context and cognition was to be located within the Ecological Systems model of Bronfenbrenner. A secondary aim of the study was to develop an index that will guide test selection and interpretation of assessment results, taking into account the influence of socio-ecological factors and providing a conceptual framework for future test development. The study employed a quantitative methodology on a South African sample consisting of primary school children aged between the ages of 6 years to 11 years. The sample was drawn from schools in the Port Elizabeth area in South Africa that were classified into low, medium, and high opportunity, based on context. The results indicated that the type of school had a significant impact on test performance, suggesting that contextual factors were influential in this process. The item analysis conducted further indicated that learners from a low opportunity school performed significantly lower than the other two schools in the sample. The index development provides a foundation for further research that would enhance the interpretation of test results. In the South African context, this is considered important, given our political history and our diversity where a “one size fits all” approach is not possible.
- Full Text:
- Date Issued: 2019
- Authors: August, Justin Oswin
- Date: 2019
- Subjects: Psychological testing
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50214 , vital:42071
- Description: With the changing landscape in South Africa to full democracy, increased research has been undertaken in the psychometric field on local and national normative studies regarding various assessment measures. Given that the Raven’s Coloured Progressive Matrices (CPM) is purported to be culture-free and not heavily dependent on verbal and language skills; it has been extensively normed throughout the world for various population groups. While norms for normal populations of children have been developed in South Africa, these studies were based on race and gender predominantly and without taking into consideration the effects of socio-ecological factors on test performance. The research study aimed to understand the influence of socio-ecological factors on the expression of cognitive scores amongst a geographically diverse sample of South African learners. Through this study, research on the interplay between context and cognition was to be located within the Ecological Systems model of Bronfenbrenner. A secondary aim of the study was to develop an index that will guide test selection and interpretation of assessment results, taking into account the influence of socio-ecological factors and providing a conceptual framework for future test development. The study employed a quantitative methodology on a South African sample consisting of primary school children aged between the ages of 6 years to 11 years. The sample was drawn from schools in the Port Elizabeth area in South Africa that were classified into low, medium, and high opportunity, based on context. The results indicated that the type of school had a significant impact on test performance, suggesting that contextual factors were influential in this process. The item analysis conducted further indicated that learners from a low opportunity school performed significantly lower than the other two schools in the sample. The index development provides a foundation for further research that would enhance the interpretation of test results. In the South African context, this is considered important, given our political history and our diversity where a “one size fits all” approach is not possible.
- Full Text:
- Date Issued: 2019
A value-based approach to promoting excellence in mathematics education
- Authors: Austin, Pamela Winifred
- Date: 2010
- Subjects: Mathematics -- Study and teaching -- South Africa , Inquiry-based learning -- South Africa , Active learning -- South Africa , Effective teaching -- South Africa , Self-efficacy
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9482 , http://hdl.handle.net/10948/1656 , Mathematics -- Study and teaching -- South Africa , Inquiry-based learning -- South Africa , Active learning -- South Africa , Effective teaching -- South Africa , Self-efficacy
- Description: This research study has emerged as a result of my concern regarding the apparent low self-efficacy amongst initial teacher education students in my mathematics education classes. It also reflects a reported renewed interest in values, and the promotion of excellence in education. The effects of a values-based approach to mathematics education towards improving students’ self-efficacy and promoting excellence have been investigated, grounded within my ontology of excellence in mathematics education, which incorporates the values of respect, fairness, accountability, honesty and compassion. An inquiry-based teaching and learning approach formed the framework within which the study took place. Notions of ‘new scholarship’, premised on the view that teaching is about engagement in participatory learning, and the development of communities of creative students, provided the theoretical framework. Both quantitative and qualitative data gathering methods were used. Data-collection tools included affective-disposition statements, interviews, journal entries, as well as a video recording of a mathematics education lesson. The quantitative and qualitative data generated suggest improved levels of self-efficacy amongst the students who participated in the study. The data also suggest that a valuesbased approach to teaching can be used as an effective approach by mathematics teachers – and mathematics teacher educators – for the purpose of promoting the pursuit of excellence. As teacher education worldwide is currently characterised by a lack of vitality in teacher preparation (Grossman, 2008), the findings of this study should provide insights for teacher educators, teachers and policy makers who wish to promote mathematics self-efficacy, excellence and facilitate enhanced vitality within the teaching profession.
- Full Text:
- Date Issued: 2010
- Authors: Austin, Pamela Winifred
- Date: 2010
- Subjects: Mathematics -- Study and teaching -- South Africa , Inquiry-based learning -- South Africa , Active learning -- South Africa , Effective teaching -- South Africa , Self-efficacy
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9482 , http://hdl.handle.net/10948/1656 , Mathematics -- Study and teaching -- South Africa , Inquiry-based learning -- South Africa , Active learning -- South Africa , Effective teaching -- South Africa , Self-efficacy
- Description: This research study has emerged as a result of my concern regarding the apparent low self-efficacy amongst initial teacher education students in my mathematics education classes. It also reflects a reported renewed interest in values, and the promotion of excellence in education. The effects of a values-based approach to mathematics education towards improving students’ self-efficacy and promoting excellence have been investigated, grounded within my ontology of excellence in mathematics education, which incorporates the values of respect, fairness, accountability, honesty and compassion. An inquiry-based teaching and learning approach formed the framework within which the study took place. Notions of ‘new scholarship’, premised on the view that teaching is about engagement in participatory learning, and the development of communities of creative students, provided the theoretical framework. Both quantitative and qualitative data gathering methods were used. Data-collection tools included affective-disposition statements, interviews, journal entries, as well as a video recording of a mathematics education lesson. The quantitative and qualitative data generated suggest improved levels of self-efficacy amongst the students who participated in the study. The data also suggest that a valuesbased approach to teaching can be used as an effective approach by mathematics teachers – and mathematics teacher educators – for the purpose of promoting the pursuit of excellence. As teacher education worldwide is currently characterised by a lack of vitality in teacher preparation (Grossman, 2008), the findings of this study should provide insights for teacher educators, teachers and policy makers who wish to promote mathematics self-efficacy, excellence and facilitate enhanced vitality within the teaching profession.
- Full Text:
- Date Issued: 2010
Coastal dune ecology and management in the Eastern Cape
- Authors: Avis, Anthony Mark
- Date: 1993
- Subjects: Sand dune ecology -- South Africa Shore protection -- South Africa Coastal zone management -- South Africa Sand dunes -- South Africa Sand dune plants -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4185 , http://hdl.handle.net/10962/d1003753
- Description: The importance of understanding the ecological functioning of coastal dune systems is emphasized as being fundamental to the correct management of the dune landscape. Dune vegetation along the Eastern Cape coastline, from Cape St Francis in the west to Kei Mouth in the east was described in terms of the distribution and phytochorological affinities of the taxa. At a regional scale species distribution was strongly influenced by both the climate, particularly rainfall, and the phytochorological affinities of the taxa. Seven communities were defined using TWINSPAN, and the interrelationships between these communities in anyone area appeared to be linked to a successional gradient. Dune Slacks are thought to play a key role in this successional sequence, and a temporal study of this community led to a conceptual model of plant succession in these dunefields. Climate, particularly rainfall and wind, are major factors influencing plant succession. Wind-borne sand causes the slacks to migrate in an easterly direction under the influence of the predominantly westerly winds, although easterly winds, mainly in summer months may reverse these trends. Autogenic changes appeared to be important in this succession, and a comparative study of a good example of a primary succession at Mtunzini in Natal was undertaken to elucidate the main mechanism of change. Eight communities that were identified here were concluded to be distnbuted along a gradient of increasing age, with successional changes predictable, linear and directional. Species were grouped in distinct zones along the continuum and edaphic changes (decrease in soil pH, increase in organic matter and exchangeable bases) were related to the community based changes in species composition. The mechanism of change supported the facilitation model of plant succession which is a modification of the original Clementsian concept. Similar results were found in the Eastern Cape, but due to the harsh environment, multiple pathways of succession exist. Data from this study lent support to the model of plant succession developed earlier, and confinned that the dune slacks played an important role in this facilitation by acting as centres of diversity. The foredunes were found to have an indirect role in protecting these slacks from salt spray and sand movement. The central theme of the management studies was to investigate the ecological consequences of recreational pressure within the dune environment. Current levels of beach utilization at East London were lower than other beaches in South Africa, but a general trend of increasing utilization due to sociopolitical changes can be expected. The suitability of questionnaire surveys to assess aspects such as the adequacy of facilities, perceptual carrying capacity and the beach users opinion of natural vegetation and preference for particular beaches was demonstrated. The dune vegetation was found to be sensitive to human trampling, but at current levels, the ecological carrying capacity will not be exceeded since results of the aerial census counts and questionnaire survey revealed that few people entered sensitive zones such as the coastal forest. More detailed long term studies on the susceptibility of dune vegetation to both trampling and off-road vehicle impacts revealed a low resilience of dune plant communities to these effects. Although susceptibility differed between the three communities tested, generally the greatest amount of damage occurred after the first few passages, and vehicles caused a more significant decrease in height when compared to trampling. Recovery rates were slow and low levels of repeated damage were sufficient to retard or prevent the recovery of the plants. Stricter control of vehicle use on beaches is therefore required, and in high use zones the ecological carrying capacity should be increased by providing access tracks if possible, or if not possible, by restricting access. A historical account of the process of dune stabilization showed that although first initiated in 1845, indigenous species were only used in the past three decades. The use of alien species has resulted in problems such as a reduction in the ecological integrity and aesthetic appeal of coastal systems. The techniques applied in the stabilization of drift sands with indigenous vegetation have been successful, as revealed by a quantitative survey of 17 sites in the Eastern Cape. Sites were grouped by multivariate analysis on the basis of their species composition, and variability between sites was dependent on the types of species planted. Selection of suitable species is therefore important and is discussed with respect to their natural distribution along the coast. The long term objective of stabilization should be the creation of functional, diverse, aesthetic ecosystems, since the intrinsic and economic value of the dune landscape for tourism lies therein. However, detailed studies should be undertaken prior to implementing a manipulative process such as dune stabilization, since ecological processes may be disrupted. An understanding of such processes is therefore important if one wishes to effectively manage the dune landscape.
- Full Text:
- Date Issued: 1993
- Authors: Avis, Anthony Mark
- Date: 1993
- Subjects: Sand dune ecology -- South Africa Shore protection -- South Africa Coastal zone management -- South Africa Sand dunes -- South Africa Sand dune plants -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4185 , http://hdl.handle.net/10962/d1003753
- Description: The importance of understanding the ecological functioning of coastal dune systems is emphasized as being fundamental to the correct management of the dune landscape. Dune vegetation along the Eastern Cape coastline, from Cape St Francis in the west to Kei Mouth in the east was described in terms of the distribution and phytochorological affinities of the taxa. At a regional scale species distribution was strongly influenced by both the climate, particularly rainfall, and the phytochorological affinities of the taxa. Seven communities were defined using TWINSPAN, and the interrelationships between these communities in anyone area appeared to be linked to a successional gradient. Dune Slacks are thought to play a key role in this successional sequence, and a temporal study of this community led to a conceptual model of plant succession in these dunefields. Climate, particularly rainfall and wind, are major factors influencing plant succession. Wind-borne sand causes the slacks to migrate in an easterly direction under the influence of the predominantly westerly winds, although easterly winds, mainly in summer months may reverse these trends. Autogenic changes appeared to be important in this succession, and a comparative study of a good example of a primary succession at Mtunzini in Natal was undertaken to elucidate the main mechanism of change. Eight communities that were identified here were concluded to be distnbuted along a gradient of increasing age, with successional changes predictable, linear and directional. Species were grouped in distinct zones along the continuum and edaphic changes (decrease in soil pH, increase in organic matter and exchangeable bases) were related to the community based changes in species composition. The mechanism of change supported the facilitation model of plant succession which is a modification of the original Clementsian concept. Similar results were found in the Eastern Cape, but due to the harsh environment, multiple pathways of succession exist. Data from this study lent support to the model of plant succession developed earlier, and confinned that the dune slacks played an important role in this facilitation by acting as centres of diversity. The foredunes were found to have an indirect role in protecting these slacks from salt spray and sand movement. The central theme of the management studies was to investigate the ecological consequences of recreational pressure within the dune environment. Current levels of beach utilization at East London were lower than other beaches in South Africa, but a general trend of increasing utilization due to sociopolitical changes can be expected. The suitability of questionnaire surveys to assess aspects such as the adequacy of facilities, perceptual carrying capacity and the beach users opinion of natural vegetation and preference for particular beaches was demonstrated. The dune vegetation was found to be sensitive to human trampling, but at current levels, the ecological carrying capacity will not be exceeded since results of the aerial census counts and questionnaire survey revealed that few people entered sensitive zones such as the coastal forest. More detailed long term studies on the susceptibility of dune vegetation to both trampling and off-road vehicle impacts revealed a low resilience of dune plant communities to these effects. Although susceptibility differed between the three communities tested, generally the greatest amount of damage occurred after the first few passages, and vehicles caused a more significant decrease in height when compared to trampling. Recovery rates were slow and low levels of repeated damage were sufficient to retard or prevent the recovery of the plants. Stricter control of vehicle use on beaches is therefore required, and in high use zones the ecological carrying capacity should be increased by providing access tracks if possible, or if not possible, by restricting access. A historical account of the process of dune stabilization showed that although first initiated in 1845, indigenous species were only used in the past three decades. The use of alien species has resulted in problems such as a reduction in the ecological integrity and aesthetic appeal of coastal systems. The techniques applied in the stabilization of drift sands with indigenous vegetation have been successful, as revealed by a quantitative survey of 17 sites in the Eastern Cape. Sites were grouped by multivariate analysis on the basis of their species composition, and variability between sites was dependent on the types of species planted. Selection of suitable species is therefore important and is discussed with respect to their natural distribution along the coast. The long term objective of stabilization should be the creation of functional, diverse, aesthetic ecosystems, since the intrinsic and economic value of the dune landscape for tourism lies therein. However, detailed studies should be undertaken prior to implementing a manipulative process such as dune stabilization, since ecological processes may be disrupted. An understanding of such processes is therefore important if one wishes to effectively manage the dune landscape.
- Full Text:
- Date Issued: 1993
Isolation, characterisation of terpenoids and biosynthesis of silver nanoparticles of acacia mearnsii de wild and acacia Karroo Hayne and their Bioassays
- Authors: Avoseh, Opeyemi Nudewhenu
- Date: 2015
- Language: English
- Type: Thesis , Doctoral , PhD (Chemistry)
- Identifier: vital:11355 , http://hdl.handle.net/10353/d1021292
- Description: Great wealth of traditional knowledge about the use of plants had been transferred from generation to generations leading to the present day drug discovery and invention of new scientific methods of isolation, purification and identification. With the discovery of new diseases and drug-resistant organisms, there is no other source or deposit of lead compounds or drugs than the plant kingdom. As a result of this, about 25% of the current drug administered owe their origin to plant sources with the view to reduce the carcinogenic effect of synthetic drugs. Volatile terpenoids among other broad spectrum of natural product had been implicated to show high therapeutic properly. In the present study, selected locally-used medicinal plants were exploited for the presence of potent bioactive compounds and ability to form nanoparticles with distinctive property for use as chemoprotective agent against inflammation, tumors, cancer and other chronic diseases. Acacia mearnsii De Wild and Acacia karroo Hayne studied in this report are known to be invasive species with no proper regulation to conserve and preserve them. However, ethnopharmacology report of these plant species in the Southern Africa region reveals that they are good antiseptic, anti-diarrhea, anti-inflammation and a forage for livestock. These plants were subjected to volatile extraction protocol of some parts of the plants (stem and leaves) followed by examination of the anti-inflammation capacity of the extracts using an animal model. In addition, the bye-product (hydrosol) from the stem bark of each species possess a high reducing and stabilizing property leading to synthesis of silver nanoparticles, followed by investigation of the anti-inflammation potential of the synthesized silver nanoparticles using animal model. The volatile oils of the leaves and stem bark of Acacia mearnsii De Wild obtained by hydro-distillation were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). Twenty, Thirty-Eight, Twenty-nine and Thirty-Eight components accounting for 93.8%, 92.1%, 78.5% and 90.9% of the total oils of the fresh, dry leaves and fresh, dry stem bark respectively. The major components of the oil were octadecyl alcohol (25.5%) and phytol (10.5%); cis-verbenol (29.5%); phytol (10.1%) and phytol (23.4%) for the fresh leaves, dried leaves, and fresh stem, dry stem bark respectively. Oral administration of essential oils at the dose of 2% showed significant (p<0.05) anti-inflammatory properties in the albumin induced test model in rats. Oils from the fresh leaves and dry stems inhibited inflammation beyond 4 h post treatment. Furthermore, the chemical composition of the essential oils obtained by hydro-distillation from the leaves and stem bark (dry and fresh) of Acacia karroo Hayne, analysed by GC-MS, shows that hexanal (10.67%) and ß-ionone (9.74%) were dominant in the dried leaves, β-pinene (14.30%), and (Z)-2-Hexen-1-ol (10.21%) in the fresh leaves while Octacosane (10.59%) and phytol (23.38%) were dominant in the dry and fresh stem respectively. The anti-inflammation ability of these oils after an albumin-induced inflammation on wistar rats, shows a significant effect at the 1st h of treatment with a significance of P< 0.01 for all part plants, while the fresh leaves shows further inhibitory activities at the 2nd h of analysis. Silver nanoparticles (AgNPs) were successfully synthesized from AgNO3 through a green route using the aqueous extract (hydrosols) of Acacia mearnsii De Wild and Acacia karroo Hayne as reducing agent and as well as capping agent. The Acacia-mediated AgNPs were characterized with the use of UV-vis absorption spectroscopy, Fourier Transform Spectroscopy (FT-IR), Transmission electron microscope (TEM), Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDX), and X-ray Diffractometry (XRD). A spherical, 10-40 nm diameter silver nanoparticles were synthesized with very low level of stability for the AMDS and the AKDS-AgNPs. In addition, nociceptive activity with a mice rat reveals higher inhibition at the neurogenic phase for the AKDS-AgNPs, while AMDS-AgNPs exhibited a high inhibition at the inflammatory phase. The potent anti-inflammatory activity of essential oils of A. mearnsii De Wild and A. karroo Hayne hereby confirmed its traditional use in treating various inflammatory diseases, while the inflammatory studies on the synthesized AgNPs reveals a very active compound which can be used as a potent opioid or non-steroidal anti-inflammatory drug (NSAID).
- Full Text:
- Date Issued: 2015
- Authors: Avoseh, Opeyemi Nudewhenu
- Date: 2015
- Language: English
- Type: Thesis , Doctoral , PhD (Chemistry)
- Identifier: vital:11355 , http://hdl.handle.net/10353/d1021292
- Description: Great wealth of traditional knowledge about the use of plants had been transferred from generation to generations leading to the present day drug discovery and invention of new scientific methods of isolation, purification and identification. With the discovery of new diseases and drug-resistant organisms, there is no other source or deposit of lead compounds or drugs than the plant kingdom. As a result of this, about 25% of the current drug administered owe their origin to plant sources with the view to reduce the carcinogenic effect of synthetic drugs. Volatile terpenoids among other broad spectrum of natural product had been implicated to show high therapeutic properly. In the present study, selected locally-used medicinal plants were exploited for the presence of potent bioactive compounds and ability to form nanoparticles with distinctive property for use as chemoprotective agent against inflammation, tumors, cancer and other chronic diseases. Acacia mearnsii De Wild and Acacia karroo Hayne studied in this report are known to be invasive species with no proper regulation to conserve and preserve them. However, ethnopharmacology report of these plant species in the Southern Africa region reveals that they are good antiseptic, anti-diarrhea, anti-inflammation and a forage for livestock. These plants were subjected to volatile extraction protocol of some parts of the plants (stem and leaves) followed by examination of the anti-inflammation capacity of the extracts using an animal model. In addition, the bye-product (hydrosol) from the stem bark of each species possess a high reducing and stabilizing property leading to synthesis of silver nanoparticles, followed by investigation of the anti-inflammation potential of the synthesized silver nanoparticles using animal model. The volatile oils of the leaves and stem bark of Acacia mearnsii De Wild obtained by hydro-distillation were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). Twenty, Thirty-Eight, Twenty-nine and Thirty-Eight components accounting for 93.8%, 92.1%, 78.5% and 90.9% of the total oils of the fresh, dry leaves and fresh, dry stem bark respectively. The major components of the oil were octadecyl alcohol (25.5%) and phytol (10.5%); cis-verbenol (29.5%); phytol (10.1%) and phytol (23.4%) for the fresh leaves, dried leaves, and fresh stem, dry stem bark respectively. Oral administration of essential oils at the dose of 2% showed significant (p<0.05) anti-inflammatory properties in the albumin induced test model in rats. Oils from the fresh leaves and dry stems inhibited inflammation beyond 4 h post treatment. Furthermore, the chemical composition of the essential oils obtained by hydro-distillation from the leaves and stem bark (dry and fresh) of Acacia karroo Hayne, analysed by GC-MS, shows that hexanal (10.67%) and ß-ionone (9.74%) were dominant in the dried leaves, β-pinene (14.30%), and (Z)-2-Hexen-1-ol (10.21%) in the fresh leaves while Octacosane (10.59%) and phytol (23.38%) were dominant in the dry and fresh stem respectively. The anti-inflammation ability of these oils after an albumin-induced inflammation on wistar rats, shows a significant effect at the 1st h of treatment with a significance of P< 0.01 for all part plants, while the fresh leaves shows further inhibitory activities at the 2nd h of analysis. Silver nanoparticles (AgNPs) were successfully synthesized from AgNO3 through a green route using the aqueous extract (hydrosols) of Acacia mearnsii De Wild and Acacia karroo Hayne as reducing agent and as well as capping agent. The Acacia-mediated AgNPs were characterized with the use of UV-vis absorption spectroscopy, Fourier Transform Spectroscopy (FT-IR), Transmission electron microscope (TEM), Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDX), and X-ray Diffractometry (XRD). A spherical, 10-40 nm diameter silver nanoparticles were synthesized with very low level of stability for the AMDS and the AKDS-AgNPs. In addition, nociceptive activity with a mice rat reveals higher inhibition at the neurogenic phase for the AKDS-AgNPs, while AMDS-AgNPs exhibited a high inhibition at the inflammatory phase. The potent anti-inflammatory activity of essential oils of A. mearnsii De Wild and A. karroo Hayne hereby confirmed its traditional use in treating various inflammatory diseases, while the inflammatory studies on the synthesized AgNPs reveals a very active compound which can be used as a potent opioid or non-steroidal anti-inflammatory drug (NSAID).
- Full Text:
- Date Issued: 2015
Enhancing productivity and market participation for poverty reduction and shared prosperity in South Africa
- Authors: Avuletey, Richard
- Date: 2017
- Subjects: Poverty -- South Africa Economic development -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/13978 , vital:39736
- Description: There have been several attempts by the South Africa government to improve the agricultural productivity on smallholder farms since the end of apartheid. In spite of the government support, agricultural productivity has stagnated for several years across the Eastern Cape rural communities including Mthatha and Qamata. The aim of this study was to understand the roles played by irrigation adoption and market participation in addressing poverty reduction and shared prosperity levels of smallholder farmers in Eastern Cape of South Africa. Data were collected using purposive and random sampling approach through the use of the snowball method. To collect data, a questionnaire was designed and administered through face-to-face interviews. Overall, 200 farmers were interviewed both at Mthatha and Qamata irrigation scheme to represent the farmers in the area. The collected data were analysed using both parametric and non-parametric methods. The non-parametric methods used include descriptive analysis, estimation of gross margins as a proxy for profitability. The Stochastic Frontier Analysis (SFA), Binomial Logistic Regression (BLR), Ordinary Least Squares (OLS), tobit censored regression and propensity score matching (PSM) were the parametric methods used in the study. Profit efficiency was measured using the normalized transcendent logarithmic profit frontier approach (Cobb-douglas). Stochastic Production Frontier (SPF) technique was used to determine the technical efficiency of individual farmers and to identify the major factors that influence technical efficiency. Binomial logistic regression was used to determine factors affecting irrigation adoption and market participation among smallholder farmers. OLS was used to estimate the impact of institutional characteristics, socio-economic and agronomic factors on smallholder farmers’ level of market participation for selected crop enterprises. Lastly, tobit regression and propensity score matching (PSM) analyses were used to estimate the impact of irrigation technology adoption on poverty reduction in the province. The results of the descriptive statistics of the overall sample revealed an average age of 61 years, and mean household size of 4.6 persons with majority of the household head having at least obtained some primary school education (59.5percent). Most of the household heads interviewed were men (68.5percent). Most farmers are single (65percent) with regard to their marital status. Farming is viewed as major source of livelihood for smallholders with an average income of R12523.37 for overall sample and income of R15559.80 and R5795.59 per crop season, respectively, for irrigators and non irrigators. Smallholder irrigators generated a higher gross margin of R7585.26, R21966.89 and R6266.07 from maize, cabbage and potato enterprises, respectively, compared to their non irrigator counterparts in maize (R131.39), cabbage (R10938.04) and potato (R3433.31) enterprises. The results of the frontier profit model revealed mean profit efficiency of 90percent, 99.99percent and 99.99percent, respectively, for maize, cabbage and potato.The binary logistic regression model for irrigation adoption indicated that years in school, cooperative membership, off-farm income, credit access and distance to market significantly explain smallholder farmers’ irrigation adoption decision. On the other hand, age of household head, market support, farm size, livestock income and distance to market were the key variables that accounted for smallholder farmers’ market participation adoption behaviour. The findings from the stochastic production frontier (SPF) indicate that smallholder farmers are technically efficient in maize and cabbage enterprises both at 99.99percent. Lastly, the findings from the Tobit regression and propensity score matching are consistent across the two methods, suggesting that being a member of irrigation adoption has a positive significant impact on income of smallholder farmers. Irrigation and market participation appear to have a significant and positive impact on smallholder poverty reduction (measured by crop income) for those farmers engaged in them. The findings from this study provide useful practical insights for policy makers, farm advisers and researchers in the design of effective and efficient policies, programmes and projects which can affect the adoption of irrigation technology and market participation.
- Full Text:
- Date Issued: 2017
- Authors: Avuletey, Richard
- Date: 2017
- Subjects: Poverty -- South Africa Economic development -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/13978 , vital:39736
- Description: There have been several attempts by the South Africa government to improve the agricultural productivity on smallholder farms since the end of apartheid. In spite of the government support, agricultural productivity has stagnated for several years across the Eastern Cape rural communities including Mthatha and Qamata. The aim of this study was to understand the roles played by irrigation adoption and market participation in addressing poverty reduction and shared prosperity levels of smallholder farmers in Eastern Cape of South Africa. Data were collected using purposive and random sampling approach through the use of the snowball method. To collect data, a questionnaire was designed and administered through face-to-face interviews. Overall, 200 farmers were interviewed both at Mthatha and Qamata irrigation scheme to represent the farmers in the area. The collected data were analysed using both parametric and non-parametric methods. The non-parametric methods used include descriptive analysis, estimation of gross margins as a proxy for profitability. The Stochastic Frontier Analysis (SFA), Binomial Logistic Regression (BLR), Ordinary Least Squares (OLS), tobit censored regression and propensity score matching (PSM) were the parametric methods used in the study. Profit efficiency was measured using the normalized transcendent logarithmic profit frontier approach (Cobb-douglas). Stochastic Production Frontier (SPF) technique was used to determine the technical efficiency of individual farmers and to identify the major factors that influence technical efficiency. Binomial logistic regression was used to determine factors affecting irrigation adoption and market participation among smallholder farmers. OLS was used to estimate the impact of institutional characteristics, socio-economic and agronomic factors on smallholder farmers’ level of market participation for selected crop enterprises. Lastly, tobit regression and propensity score matching (PSM) analyses were used to estimate the impact of irrigation technology adoption on poverty reduction in the province. The results of the descriptive statistics of the overall sample revealed an average age of 61 years, and mean household size of 4.6 persons with majority of the household head having at least obtained some primary school education (59.5percent). Most of the household heads interviewed were men (68.5percent). Most farmers are single (65percent) with regard to their marital status. Farming is viewed as major source of livelihood for smallholders with an average income of R12523.37 for overall sample and income of R15559.80 and R5795.59 per crop season, respectively, for irrigators and non irrigators. Smallholder irrigators generated a higher gross margin of R7585.26, R21966.89 and R6266.07 from maize, cabbage and potato enterprises, respectively, compared to their non irrigator counterparts in maize (R131.39), cabbage (R10938.04) and potato (R3433.31) enterprises. The results of the frontier profit model revealed mean profit efficiency of 90percent, 99.99percent and 99.99percent, respectively, for maize, cabbage and potato.The binary logistic regression model for irrigation adoption indicated that years in school, cooperative membership, off-farm income, credit access and distance to market significantly explain smallholder farmers’ irrigation adoption decision. On the other hand, age of household head, market support, farm size, livestock income and distance to market were the key variables that accounted for smallholder farmers’ market participation adoption behaviour. The findings from the stochastic production frontier (SPF) indicate that smallholder farmers are technically efficient in maize and cabbage enterprises both at 99.99percent. Lastly, the findings from the Tobit regression and propensity score matching are consistent across the two methods, suggesting that being a member of irrigation adoption has a positive significant impact on income of smallholder farmers. Irrigation and market participation appear to have a significant and positive impact on smallholder poverty reduction (measured by crop income) for those farmers engaged in them. The findings from this study provide useful practical insights for policy makers, farm advisers and researchers in the design of effective and efficient policies, programmes and projects which can affect the adoption of irrigation technology and market participation.
- Full Text:
- Date Issued: 2017
Development of styrene based imprinted sorbents for selective clean-up of metalloporphyrins in organic media
- Authors: Awokoya, Kehinde Nurudeen
- Date: 2014
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/54521 , vital:26580
- Description: Most crude oils contain traces of vanadium and nickel complex with porphyrins (VTPP and NTPP) within their asphaltene fraction. Although these metals are only present in trace quantities, they have a significant and detrimental impact on the refining process by degrading the quality of intermediate and end products. Therefore, their selective removal is highly desirable. This thesis presents the development of nickel porphyrin, nickel vanadyl porphyrin imprinted nanofibers and vanadyl porphyrin imprinted polymer (MIP) particles for application as selective sorbents. Computational model based on the combination of molecular dynamics simulations and quantum mechanics was successfully applied to the styrene functional monomer selection. The particle was prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The morphologies, thermal stabilities and porosities of the imprinted sorbents were studied using SEM, TGA, and BET nitrogen gas adsorption. Chloroform was found to swell the polymer particles to a higher degree than methanol and acetonitrile. The adsorption characteristics of the imprinted sorbents best fitted with Freundlich isotherm model. The imprinted sorbents recorded high extraction efficiencies (EEs) of > 99 % in selectively extracting the metalloporphyrins. The impact of the template on the affinity of recognition for NTPP was evaluated. The results showed that the NTPP adsorption capacity increased as the molar ratio of NTPP to styrene was increased from 1:1 to 3:1. The optimal ratio of template to functional monomer which yielded the best specific affinity and highest recovery (99.9 %) was 3:1. The effects of trifluoroacetic acid (TFA), dichloromethane (DCM), dimethyl sulphoxide (DMSO), pentane (PEN) on electro-spinnability of the polymer solutions and the morphological appearance of the nanofibers were investigated. The imprinted nanofibers exhibited the same selectivity specialism for both NTPP and VTPP. A remarkable stability in relation to reusability was observed when imprinted nanofibers were used, as they could be reused nine times without incurring any significant loss in removal efficiency. The results were validated by analysing a certified reference material. The imprinted sorbents were therefore found to be selective sorbents that are well suited for handling trace metals in organic media.
- Full Text:
- Date Issued: 2014
- Authors: Awokoya, Kehinde Nurudeen
- Date: 2014
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/54521 , vital:26580
- Description: Most crude oils contain traces of vanadium and nickel complex with porphyrins (VTPP and NTPP) within their asphaltene fraction. Although these metals are only present in trace quantities, they have a significant and detrimental impact on the refining process by degrading the quality of intermediate and end products. Therefore, their selective removal is highly desirable. This thesis presents the development of nickel porphyrin, nickel vanadyl porphyrin imprinted nanofibers and vanadyl porphyrin imprinted polymer (MIP) particles for application as selective sorbents. Computational model based on the combination of molecular dynamics simulations and quantum mechanics was successfully applied to the styrene functional monomer selection. The particle was prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The morphologies, thermal stabilities and porosities of the imprinted sorbents were studied using SEM, TGA, and BET nitrogen gas adsorption. Chloroform was found to swell the polymer particles to a higher degree than methanol and acetonitrile. The adsorption characteristics of the imprinted sorbents best fitted with Freundlich isotherm model. The imprinted sorbents recorded high extraction efficiencies (EEs) of > 99 % in selectively extracting the metalloporphyrins. The impact of the template on the affinity of recognition for NTPP was evaluated. The results showed that the NTPP adsorption capacity increased as the molar ratio of NTPP to styrene was increased from 1:1 to 3:1. The optimal ratio of template to functional monomer which yielded the best specific affinity and highest recovery (99.9 %) was 3:1. The effects of trifluoroacetic acid (TFA), dichloromethane (DCM), dimethyl sulphoxide (DMSO), pentane (PEN) on electro-spinnability of the polymer solutions and the morphological appearance of the nanofibers were investigated. The imprinted nanofibers exhibited the same selectivity specialism for both NTPP and VTPP. A remarkable stability in relation to reusability was observed when imprinted nanofibers were used, as they could be reused nine times without incurring any significant loss in removal efficiency. The results were validated by analysing a certified reference material. The imprinted sorbents were therefore found to be selective sorbents that are well suited for handling trace metals in organic media.
- Full Text:
- Date Issued: 2014
Functional changes of the vasculature in HIV/AIDS patients on Haart and Haart Naïve HIV participants
- Authors: Awotedu, Kofoworola Olajire
- Date: 2013
- Subjects: Cardiovascular system -- Diseases HIV infections -- Treatment
- Language: English
- Type: Thesis , Doctoral , Ph D
- Identifier: http://hdl.handle.net/11260/185 , vital:21366
- Description: The present study sought to explore the functional changes that occur in the vasculature of HIV positive participants of African origin in Mthatha district of South africa which might lead to increased risk in their cardiovascular system. Available literature shows that arterial stiffness plays an important role in cardiovascular events such as stroke, vasculitis and myocardial infarction. Measurement of (aortic pulse wave velocity; PWV) provides some of the strongest evidence concerning the prognostic significance of large artery stiffening. This study was aimed at investigating the relationship between anthropometry, age, E-Selectin level, cytokine levels, haemodynamic variables, blood counts and blood lipid profile with pulse wave velocity. Some traditional cardiovascular risk factors such as alcohol, and smoking were also taken into account. This was a cross-sectional study comprising of 169 participants (62 males and 107 females). 63 were HIV negative (group A), 54 HIV positive on treatment (group B), and 52 were HIV positive not on treatment (group C). Pulse wave velocity (PWV) was assessed using the Sphygmocor Vx. Statistically, ANOVA was used for variables with normal distribution and non parametric tests were used for variables with skewed distribution. Notable significant differences were seen in the means of the following variables across all the 3 groups. Conclusion: This study showed that HIV infected patients with or without antiretroviral therapy have increase arterial stiffness which is associated with an increased cardiovascular risk. The sphygmocor is an accurate, non invassive and useful tool in the evaluation of arterial stiffness and its use in clinical practice should be encouraged. PWV and the augmentation index (AIx) are the two major non- iv invasive methods of assessing arterial stiffness. Life style modification should be incorporated into the management of HIV patients so as the continuous monitoring of their haematological and lipid profile.
- Full Text:
- Date Issued: 2013
Functional changes of the vasculature in HIV/AIDS patients on Haart and Haart Naïve HIV participants
- Authors: Awotedu, Kofoworola Olajire
- Date: 2013
- Subjects: Cardiovascular system -- Diseases HIV infections -- Treatment
- Language: English
- Type: Thesis , Doctoral , Ph D
- Identifier: http://hdl.handle.net/11260/185 , vital:21366
- Description: The present study sought to explore the functional changes that occur in the vasculature of HIV positive participants of African origin in Mthatha district of South africa which might lead to increased risk in their cardiovascular system. Available literature shows that arterial stiffness plays an important role in cardiovascular events such as stroke, vasculitis and myocardial infarction. Measurement of (aortic pulse wave velocity; PWV) provides some of the strongest evidence concerning the prognostic significance of large artery stiffening. This study was aimed at investigating the relationship between anthropometry, age, E-Selectin level, cytokine levels, haemodynamic variables, blood counts and blood lipid profile with pulse wave velocity. Some traditional cardiovascular risk factors such as alcohol, and smoking were also taken into account. This was a cross-sectional study comprising of 169 participants (62 males and 107 females). 63 were HIV negative (group A), 54 HIV positive on treatment (group B), and 52 were HIV positive not on treatment (group C). Pulse wave velocity (PWV) was assessed using the Sphygmocor Vx. Statistically, ANOVA was used for variables with normal distribution and non parametric tests were used for variables with skewed distribution. Notable significant differences were seen in the means of the following variables across all the 3 groups. Conclusion: This study showed that HIV infected patients with or without antiretroviral therapy have increase arterial stiffness which is associated with an increased cardiovascular risk. The sphygmocor is an accurate, non invassive and useful tool in the evaluation of arterial stiffness and its use in clinical practice should be encouraged. PWV and the augmentation index (AIx) are the two major non- iv invasive methods of assessing arterial stiffness. Life style modification should be incorporated into the management of HIV patients so as the continuous monitoring of their haematological and lipid profile.
- Full Text:
- Date Issued: 2013
A framework for grain commodity trading decision support in South Africa
- Authors: Ayankoya, Kayode Anthony
- Date: 2016
- Subjects: Grain trade -- South Africa Commodity exchanges -- South Africa Food industry and trade -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/11437 , vital:26925
- Description: In several countries around the world, grain commodities are traded as assets on stock exchanges. This indicate that the market and effectively the prices of the grain commodities in such countries, are controlled by several local and international economic, political and social factors that are rapidly changing. As a result, the prices of some grain commodities are volatile and trading in such commodities are prone to price-related risks. There are different trading strategies for minimising price-related risks and maximising profits. But empirical research suggests that making the right decision for effective grain commodities trading has been a difficult task for stakeholders due to high volatility of grain commodities prices. Studies have shown that this is more challenging among grain commodities farmers because of their lack of skills and the time to sift through and make sense of the datasets on the plethora of factors that influence the grain commodities market. This thesis focused on providing an answer for the main research problem that grain farmers in South Africa do not take full advantage of all the available strategies for trading their grain commodities because of the complexities associated with monitoring the large datasets that influence the grain commodities market. The main objective set by this study is to design a framework that can be followed to collect, integrate and analyse datasets that influence trading decisions of grain farmers in South Africa about grain commodities. This study takes advantage of the developments in Big Data and Data Science to achieve the set objective using the Design Science Research (DSR) methodology. The prediction of future prices of grain commodities for the different trading strategies was identified as an important factor for making better decisions when trading grain commodities and the key factors that influence the prices were identified. This was followed by a critical review of the literature to determine how the concepts of Big Data and Data Science can be leveraged for an effective grain commodities trading decision support. This resulted in a proposed framework for grain commodities trading. The proposed framework suggested an investigation of the factors that influence the prices of grain commodities as the basis for acquiring the relevant datasets. The proposed framework suggested the adoption of the Big Data approach in acquiring, preparing and integrating relevant datasets from several sources. Furthermore, it was suggested that algorithmic models for predicting grain commodities prices can be developed on top of the data layer of the proposed framework to provide real-time decision support. The proposed framework suggests the need for a carefully designed visualisation of the result and the collected data that promotes user experience. Lastly, the proposed framework included a technology consideration component to support the Big Data and Data Science approach of the framework. To demonstrate that the proposed framework addressed the main problem of this research, datasets from several sources on trading white maize in South Africa and the factors that influence market were streamed, integrated and analysed. Backpropagation Neural Network algorithm was used for modelling the prices of white maize for spot and futures trading strategies were predicted. There are other modelling techniques such as the Box-Jenkins statistical time series analysis methodology. But, Neural Networks was identified as more suitable for time series data with complex patterns and relationships. A demonstration system was setup to provide effective decision support by using near real-time data to provide a dynamic predictive analytics for the spot and December futures contract prices of white maize in South Africa. Comparative analysis of predictions made using the model from the proposed framework to actual data indicated a significant degree of accuracy. A further evaluation was carried out by asking experienced traders to make predictions for the spot and December futures contract prices of white maize. The result of the exercise indicated that the predictions from the developed model were much closer to the actual prices. This indicated that the proposed framework is technically capable and generally useful. It also shows that the proposed framework can be used to provide decision support about trading grain commodities to stakeholders with lesser skills, experience and resources. The practical contribution of this thesis is that relevant datasets from several sources can be streamed into an integrated data source in real-time, which can be used as input for a real-time learning algorithmic model for predicting grain commodities prices. This will make it possible for a predictive analytics that responds to market volatility thereby providing an effective decision support for grain commodities trading. Another practical contribution of this thesis is a proposed framework that can be followed for developing a Decision Support System for trading in grain commodities. This thesis made theoretical contributions by building on the information processing theory and the decision making theory. The theoretical contribution of this thesis consists of the identification of Big Data approach, tools and techniques for eradicating uncertainty and equivocality in grain commodities trading decision making process.
- Full Text:
- Date Issued: 2016
- Authors: Ayankoya, Kayode Anthony
- Date: 2016
- Subjects: Grain trade -- South Africa Commodity exchanges -- South Africa Food industry and trade -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/11437 , vital:26925
- Description: In several countries around the world, grain commodities are traded as assets on stock exchanges. This indicate that the market and effectively the prices of the grain commodities in such countries, are controlled by several local and international economic, political and social factors that are rapidly changing. As a result, the prices of some grain commodities are volatile and trading in such commodities are prone to price-related risks. There are different trading strategies for minimising price-related risks and maximising profits. But empirical research suggests that making the right decision for effective grain commodities trading has been a difficult task for stakeholders due to high volatility of grain commodities prices. Studies have shown that this is more challenging among grain commodities farmers because of their lack of skills and the time to sift through and make sense of the datasets on the plethora of factors that influence the grain commodities market. This thesis focused on providing an answer for the main research problem that grain farmers in South Africa do not take full advantage of all the available strategies for trading their grain commodities because of the complexities associated with monitoring the large datasets that influence the grain commodities market. The main objective set by this study is to design a framework that can be followed to collect, integrate and analyse datasets that influence trading decisions of grain farmers in South Africa about grain commodities. This study takes advantage of the developments in Big Data and Data Science to achieve the set objective using the Design Science Research (DSR) methodology. The prediction of future prices of grain commodities for the different trading strategies was identified as an important factor for making better decisions when trading grain commodities and the key factors that influence the prices were identified. This was followed by a critical review of the literature to determine how the concepts of Big Data and Data Science can be leveraged for an effective grain commodities trading decision support. This resulted in a proposed framework for grain commodities trading. The proposed framework suggested an investigation of the factors that influence the prices of grain commodities as the basis for acquiring the relevant datasets. The proposed framework suggested the adoption of the Big Data approach in acquiring, preparing and integrating relevant datasets from several sources. Furthermore, it was suggested that algorithmic models for predicting grain commodities prices can be developed on top of the data layer of the proposed framework to provide real-time decision support. The proposed framework suggests the need for a carefully designed visualisation of the result and the collected data that promotes user experience. Lastly, the proposed framework included a technology consideration component to support the Big Data and Data Science approach of the framework. To demonstrate that the proposed framework addressed the main problem of this research, datasets from several sources on trading white maize in South Africa and the factors that influence market were streamed, integrated and analysed. Backpropagation Neural Network algorithm was used for modelling the prices of white maize for spot and futures trading strategies were predicted. There are other modelling techniques such as the Box-Jenkins statistical time series analysis methodology. But, Neural Networks was identified as more suitable for time series data with complex patterns and relationships. A demonstration system was setup to provide effective decision support by using near real-time data to provide a dynamic predictive analytics for the spot and December futures contract prices of white maize in South Africa. Comparative analysis of predictions made using the model from the proposed framework to actual data indicated a significant degree of accuracy. A further evaluation was carried out by asking experienced traders to make predictions for the spot and December futures contract prices of white maize. The result of the exercise indicated that the predictions from the developed model were much closer to the actual prices. This indicated that the proposed framework is technically capable and generally useful. It also shows that the proposed framework can be used to provide decision support about trading grain commodities to stakeholders with lesser skills, experience and resources. The practical contribution of this thesis is that relevant datasets from several sources can be streamed into an integrated data source in real-time, which can be used as input for a real-time learning algorithmic model for predicting grain commodities prices. This will make it possible for a predictive analytics that responds to market volatility thereby providing an effective decision support for grain commodities trading. Another practical contribution of this thesis is a proposed framework that can be followed for developing a Decision Support System for trading in grain commodities. This thesis made theoretical contributions by building on the information processing theory and the decision making theory. The theoretical contribution of this thesis consists of the identification of Big Data approach, tools and techniques for eradicating uncertainty and equivocality in grain commodities trading decision making process.
- Full Text:
- Date Issued: 2016
Mannich base metal complexes and their thiocyanate analogues as catalysts in the oxidation of Catechol
- Authors: Ayeni, Ayowole Olaolu
- Date: 2018
- Subjects: Mannich bases , Catechol , Catechol -- Oxidation , Thiocyanates , Catalysts
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62339 , vital:28156
- Description: The study focused on the design of new Cu(II) and Fe(III) complexes, with or without thiocyanate (NCS-), as possible candidates of catechol oxidation using 3,5-di-tert-butyl catechol (3,5-DTBC) as substrate. Two classes of Mannich bases were studied depending on the active methylene group from which they were formed, being either p-cresol or acetaminophen. The ligands were characterised by 1H and 13C NMR spectroscopy. Crystal structures of three of the ligands are newly reported, along with detailed discussion of polymorphism observed in one of the ligands, and the nature of the hydrogen within the ligands in the solid state as well as in solution. The Mannich bases behaved as bidentate (NO), tridentate (NNO) and tetradentate (NNOO) ligands on coordination to Cu(II) and Fe(III) ions in which the hydroxyl group may be protonated or deprotonated. Coordination was determined by IR spectroscopy, investigating shifts in vOH, vC-O and in vCNC of the Mannich bases. The vCNC stretching frequencies v1 and v2 of asymmetrical piperazine Mannich bases were observed to shift upward in few cases upon complexation and this is attributed to (chair-boat) conformational change. The mode of coordination of the thiocyanate was determined by IR spectroscopy. Of the forty metal complexes investigated, six groups of metal complexes were identified as follows: (i) Ma(Ln)aClb-cH2O; (ii) Ma(HLn)a(NCS)aClb; (iii) Ma(Ln)a(NCS)aClb; (iv) Ma(HLn)aClb-cH2O; (v) Ma(Ln)a(NCS)a-cH2O; (vi) Ma(HLn)a(NCS)a-cH2O where a = 1 - 2 ; b = 1 - 4, c = 1 - 8. Molar conductivity values of 4.38 - 161.77 Q-1.cm2.mol-1 for the Cu(II) and Fe(III) complexes in DMSO showed that they range from non-electrolytes to 1:1 and 1:2 electrolytes. Electronic spectra for the ligands and the complexes were conducted in DMF and DMSO. The ligands are characterised by and n→n* and n→n* transitions. Intraligand charge transfer transitions peculiar to the nitro group were observed at about 430 nm for the nitro containing ligands. On coordination, these bands overshadowed the d-d transitions particularly for the nitro-Mannich bases. On complexation, ligand to metal charge transfer transitions associated with the hydroxyl were observed between 320 - 420 nm. Charge transfer transitions associated with the thiocyanates were also observed and discussed. The d-d transitions for high spin Fe(III) complexes are spin forbidden and generally uninformative. Those of Cu(II) are spin allowed and allow tentative structural proposals. Square planar and octahedral geometry are generally prevalent in the Cu(II) complexes with trigonal bipyramidal observed in few instances. The Fe(III) complexes are generally octahedral. Thirty-nine of the forty synthesised Cu(II) and Fe(III) complexes were catalytically active on the substrate (3,5-DTBC) in DMF with turnover rates (kcat) reported in the range of 1.86 ± 0.09 to 112.32 ± 3.72 h-1. From this pool of complexes, sixteen isostructural pairs were identified in terms of geometry, molecular formula and the source of the Mannich base and the following conclusions were made: The presence of thiocyanate in the metal complexes reduce catecholase activity; the Cu(II) complexes generally have better activity but the Fe(III) complexes become more relatively active with highly electron donating groups while the Cu(II) complexes become less; dinuclear complexes have greater activity than the mononuclear.
- Full Text:
- Date Issued: 2018
- Authors: Ayeni, Ayowole Olaolu
- Date: 2018
- Subjects: Mannich bases , Catechol , Catechol -- Oxidation , Thiocyanates , Catalysts
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62339 , vital:28156
- Description: The study focused on the design of new Cu(II) and Fe(III) complexes, with or without thiocyanate (NCS-), as possible candidates of catechol oxidation using 3,5-di-tert-butyl catechol (3,5-DTBC) as substrate. Two classes of Mannich bases were studied depending on the active methylene group from which they were formed, being either p-cresol or acetaminophen. The ligands were characterised by 1H and 13C NMR spectroscopy. Crystal structures of three of the ligands are newly reported, along with detailed discussion of polymorphism observed in one of the ligands, and the nature of the hydrogen within the ligands in the solid state as well as in solution. The Mannich bases behaved as bidentate (NO), tridentate (NNO) and tetradentate (NNOO) ligands on coordination to Cu(II) and Fe(III) ions in which the hydroxyl group may be protonated or deprotonated. Coordination was determined by IR spectroscopy, investigating shifts in vOH, vC-O and in vCNC of the Mannich bases. The vCNC stretching frequencies v1 and v2 of asymmetrical piperazine Mannich bases were observed to shift upward in few cases upon complexation and this is attributed to (chair-boat) conformational change. The mode of coordination of the thiocyanate was determined by IR spectroscopy. Of the forty metal complexes investigated, six groups of metal complexes were identified as follows: (i) Ma(Ln)aClb-cH2O; (ii) Ma(HLn)a(NCS)aClb; (iii) Ma(Ln)a(NCS)aClb; (iv) Ma(HLn)aClb-cH2O; (v) Ma(Ln)a(NCS)a-cH2O; (vi) Ma(HLn)a(NCS)a-cH2O where a = 1 - 2 ; b = 1 - 4, c = 1 - 8. Molar conductivity values of 4.38 - 161.77 Q-1.cm2.mol-1 for the Cu(II) and Fe(III) complexes in DMSO showed that they range from non-electrolytes to 1:1 and 1:2 electrolytes. Electronic spectra for the ligands and the complexes were conducted in DMF and DMSO. The ligands are characterised by and n→n* and n→n* transitions. Intraligand charge transfer transitions peculiar to the nitro group were observed at about 430 nm for the nitro containing ligands. On coordination, these bands overshadowed the d-d transitions particularly for the nitro-Mannich bases. On complexation, ligand to metal charge transfer transitions associated with the hydroxyl were observed between 320 - 420 nm. Charge transfer transitions associated with the thiocyanates were also observed and discussed. The d-d transitions for high spin Fe(III) complexes are spin forbidden and generally uninformative. Those of Cu(II) are spin allowed and allow tentative structural proposals. Square planar and octahedral geometry are generally prevalent in the Cu(II) complexes with trigonal bipyramidal observed in few instances. The Fe(III) complexes are generally octahedral. Thirty-nine of the forty synthesised Cu(II) and Fe(III) complexes were catalytically active on the substrate (3,5-DTBC) in DMF with turnover rates (kcat) reported in the range of 1.86 ± 0.09 to 112.32 ± 3.72 h-1. From this pool of complexes, sixteen isostructural pairs were identified in terms of geometry, molecular formula and the source of the Mannich base and the following conclusions were made: The presence of thiocyanate in the metal complexes reduce catecholase activity; the Cu(II) complexes generally have better activity but the Fe(III) complexes become more relatively active with highly electron donating groups while the Cu(II) complexes become less; dinuclear complexes have greater activity than the mononuclear.
- Full Text:
- Date Issued: 2018
Molecular epidemiology of vibrio pathogens in selected surface waters and treated final effluents of wastewater treatment plants in Chris Hani District Municipality in the Eastern Cape Province, South Africa
- Authors: Ayodeji, Onsula Charles
- Date: 2018
- Subjects: Sewage disposal plants Sewage -- Purification Water -- Purification -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , Microbiology
- Identifier: http://hdl.handle.net/10353/10464 , vital:35478
- Description: Access to clean and safe water is essential for the survival of human beings. Nevertheless pollution from wastewater treatment plants (WWTPs) effluents often impacts the microbiological qualities of surface waters. Availability of freshwater resources is indispensable for preventing waterborne diseases. The current study evaluated the physicochemical properties and abundance of Vibrio species in selected rivers and WWTPs in the Eastern Cape Province of South Africa, over a one year sampling regime (December, 2016 to November, 2017). Water samples were collected monthly at designated locations along the banks of two rivers, treated effluents from 500 m upstream and downstream discharge points of two WWTPs and examined for physicochemical qualities, prevalence of Vibrio pathogens and their antibiogram profiles using both cultural and molecular techniques. The findings reveal the qualities of Tsomo and Great Fish river qualities with respect to electrical conductivity (EC) (137.75 – 377.69 mg/l), total suspended solids (TSS) (52.00 – 725.19 mg/l) and temperature (12.7 – 23 oC) and the treated effluents of WW-AD and WW-CR WWTPs with respect to EC (525.73 – 1071.89 mg/l), free chlorine (0.00 mg/l – 0.68 mg/l), temperature (12.4 – 28.8 oC), TSS (14.67 – 276.44 mg/l) exceeds the permissible limits set for effluent discharged to freshwater by South Africa guidelines. Other physicochemical qualities such as turbidity (63.11 – 797.17 NTU), BOD (3.30 – 5.26 mg/l) and TDS (68.88 – 148.14 mg/l) for Tsomo and Great Fish river and turbidity (20.33 – 310 NTU), biological oxygen demand (BOD) (1.28 – 4.96 mg/l), and total dissolve solid (TDS) (262.89 – 534.89 mg/l) for WWTPs WW-AD and WW-CR did not comply with WHO and EU standards as no regulation is set for them in the South African guidelines for domestic water usage. Statistical analysis revealed that pH, electrical conductivities, dissolved oxygen and total dissolved solid were significantly different whereas temperature did not differ significantly with respect to the four seasons (P < 0.05). The Vibrio densities for Great Fish river ranged between 0 and 3.29 log10 CFU/ml with the highest obtained in the spring. The Tsomo River Vibrio densities varied between 0 to 3.56 log10 CFU/ml and the maximum densities recorded during summer. The presumptive Vibrio densities in WW-AD and WW-CR WWTPs ranged from 0 to 3.67 log10 CFU/ml and 0 to 4.42 log10 CFU/ml with autumn and spring having the highest loads respectively. Molecular identification of the presumptive Vibrio species revealed 424 positive for the Vibrio genus. Of these, 21.69 percent, 11.79 percent, 8.25 percent and 2.12 percent were confirmed as V. cholerae, V. mimicus, V. parahaemolyticus and V. fluvialis respectively. The presence of potentially Vibrio pathogens in the rivers and treated effluents suggests potential public health threat to the communities relying on receiving watersheds where the effluents are discharged. Results of antibiotic sensitivity testing revealed high sensitivities against Ofloxacin (85.54 percent), Cefuroxime (81.93 percent), and Ciprofloxacin (74.70 percent), whereas resistance against other antibiotics follow this order: Imipenem (42.17 percent), Amoxicillin-Clavulanic Acid (54.17 percent), Ampicillin (63.54 percent), Nitrofurantoin (71.79 percent) and Polymyxin B (97.44 percent). Surprisingly, the resistance of Vibrio species against the known effective Carbapenems was relatively high (Meropenem (38.54 percent) and Imipenem (58.88 percent). Multiple antibiotic resistance phenotypes (MARP) of the isolates were resistant to two or more antibiotics whereas the calculated multiple antibiotic resistance index (MARI) ranged from 0.2 to 0.7. The observed high multiple antibiotics index suggest the recovered Vibrio pathogens are of high antimicrobial usage origin. Increase in antimicrobial resistance profiles towards conventionally used antibiotics as indicated in this study calls for adequate sanitation facilities and proper surveillance programs towards monitoring of antimicrobial resistance determinants in wastewater treatment effluents and receiving watersheds. This will in turn enhance early detection of resistant strains of public health importance, and supports the prompt notification and investigation of outbreaks. It further advocates the need for constant monitoring programme by the relevant regulatory agencies to ensure total compliance of the wastewater treatment facilities to the stipulated standards.
- Full Text:
- Date Issued: 2018
- Authors: Ayodeji, Onsula Charles
- Date: 2018
- Subjects: Sewage disposal plants Sewage -- Purification Water -- Purification -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , Microbiology
- Identifier: http://hdl.handle.net/10353/10464 , vital:35478
- Description: Access to clean and safe water is essential for the survival of human beings. Nevertheless pollution from wastewater treatment plants (WWTPs) effluents often impacts the microbiological qualities of surface waters. Availability of freshwater resources is indispensable for preventing waterborne diseases. The current study evaluated the physicochemical properties and abundance of Vibrio species in selected rivers and WWTPs in the Eastern Cape Province of South Africa, over a one year sampling regime (December, 2016 to November, 2017). Water samples were collected monthly at designated locations along the banks of two rivers, treated effluents from 500 m upstream and downstream discharge points of two WWTPs and examined for physicochemical qualities, prevalence of Vibrio pathogens and their antibiogram profiles using both cultural and molecular techniques. The findings reveal the qualities of Tsomo and Great Fish river qualities with respect to electrical conductivity (EC) (137.75 – 377.69 mg/l), total suspended solids (TSS) (52.00 – 725.19 mg/l) and temperature (12.7 – 23 oC) and the treated effluents of WW-AD and WW-CR WWTPs with respect to EC (525.73 – 1071.89 mg/l), free chlorine (0.00 mg/l – 0.68 mg/l), temperature (12.4 – 28.8 oC), TSS (14.67 – 276.44 mg/l) exceeds the permissible limits set for effluent discharged to freshwater by South Africa guidelines. Other physicochemical qualities such as turbidity (63.11 – 797.17 NTU), BOD (3.30 – 5.26 mg/l) and TDS (68.88 – 148.14 mg/l) for Tsomo and Great Fish river and turbidity (20.33 – 310 NTU), biological oxygen demand (BOD) (1.28 – 4.96 mg/l), and total dissolve solid (TDS) (262.89 – 534.89 mg/l) for WWTPs WW-AD and WW-CR did not comply with WHO and EU standards as no regulation is set for them in the South African guidelines for domestic water usage. Statistical analysis revealed that pH, electrical conductivities, dissolved oxygen and total dissolved solid were significantly different whereas temperature did not differ significantly with respect to the four seasons (P < 0.05). The Vibrio densities for Great Fish river ranged between 0 and 3.29 log10 CFU/ml with the highest obtained in the spring. The Tsomo River Vibrio densities varied between 0 to 3.56 log10 CFU/ml and the maximum densities recorded during summer. The presumptive Vibrio densities in WW-AD and WW-CR WWTPs ranged from 0 to 3.67 log10 CFU/ml and 0 to 4.42 log10 CFU/ml with autumn and spring having the highest loads respectively. Molecular identification of the presumptive Vibrio species revealed 424 positive for the Vibrio genus. Of these, 21.69 percent, 11.79 percent, 8.25 percent and 2.12 percent were confirmed as V. cholerae, V. mimicus, V. parahaemolyticus and V. fluvialis respectively. The presence of potentially Vibrio pathogens in the rivers and treated effluents suggests potential public health threat to the communities relying on receiving watersheds where the effluents are discharged. Results of antibiotic sensitivity testing revealed high sensitivities against Ofloxacin (85.54 percent), Cefuroxime (81.93 percent), and Ciprofloxacin (74.70 percent), whereas resistance against other antibiotics follow this order: Imipenem (42.17 percent), Amoxicillin-Clavulanic Acid (54.17 percent), Ampicillin (63.54 percent), Nitrofurantoin (71.79 percent) and Polymyxin B (97.44 percent). Surprisingly, the resistance of Vibrio species against the known effective Carbapenems was relatively high (Meropenem (38.54 percent) and Imipenem (58.88 percent). Multiple antibiotic resistance phenotypes (MARP) of the isolates were resistant to two or more antibiotics whereas the calculated multiple antibiotic resistance index (MARI) ranged from 0.2 to 0.7. The observed high multiple antibiotics index suggest the recovered Vibrio pathogens are of high antimicrobial usage origin. Increase in antimicrobial resistance profiles towards conventionally used antibiotics as indicated in this study calls for adequate sanitation facilities and proper surveillance programs towards monitoring of antimicrobial resistance determinants in wastewater treatment effluents and receiving watersheds. This will in turn enhance early detection of resistant strains of public health importance, and supports the prompt notification and investigation of outbreaks. It further advocates the need for constant monitoring programme by the relevant regulatory agencies to ensure total compliance of the wastewater treatment facilities to the stipulated standards.
- Full Text:
- Date Issued: 2018
"Speak American"! or language, power and education in Dearborn, Michigan: a case study of Arabic heritage learners and their community
- Authors: Ayouby, Kenneth Kahtan
- Date: 2004
- Subjects: Arabic language -- Study and teaching (Higher) -- Michigan -- Dearborn , Education and language -- Michigan -- Dearborn
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:11015 , http://hdl.handle.net/10948/369 , Arabic language -- Study and teaching (Higher) -- Michigan -- Dearborn , Education and language -- Michigan -- Dearborn
- Description: This study examines the history and development of the “Arabic as a foreign language” (AFL) programme in Dearborn Public Schools (in Michigan, the United States) in its socio-cultural and political context. More specifically, this study examines the significance of Arabic to the Arab immigrant and ethnic community in Dearborn in particular, but with reference to meanings generated and associated to Arabic by non- Arabs in the same locale. Although this study addresses questions similar to research conducted on Arab Americans in light of anthropological and sociological theoretical constructs, it is, however, unique in examining education and Arabic pedagogy in Dearborn from an Arab American studies and an educational multi-cultural perspective, predicated on/and drawing from Edward Said’s critique of Orientalism, Paulo Freire’s ideas about education, and Henry Giroux’s concern with critical pedagogy. In the American mindscape, the "East" has been the theatre of the exotic, the setting of the Other from colonial times to the present. The Arab and Muslim East have been constructed to represent an opposite of American culture, values and life. Through the agency of conflation, Arab (and Muslim) Americans are accordingly lumped together with people from abroad, making for their status as permanent outsiders. Thus, if the American Self represents an ideal, the inhabitants of this oppositional world of Arabs and Islam (an Anti-world) represent an Anti-self. A source of fear and object of hate and prejudice, this Anti-self is the object of derision and anything connected with it (e.g. language, customs, religion, etc.) becomes suspect and is devalued by association. This document has two objectives: First, to present an historical account of this context, and, secondly, to shed light on how and why things that are associated with Arab Americans in Dearborn are devalued. This is achieved by addressing the developments of meanings (of actions and symbols) in their American context, and how they have shaped (and still shape) the local culture's depiction of and understanding of Arab (and Muslim) Americans. Therefore, Arab American issues of language, culture and societal interactions should be understood as constituting a stream of American life, which represent a dimension of the total American experience, past and present, that is best understood through the paradigm of American studies. Viewing this experience as a cultural whole rather than as a series of unrelated fragments (e.g. immigration waves and settlement patterns, religious and state affiliations, assimilation and preservation debates), Arab American culture and issues begin to shine through as an organic and holistic experience whose characteristics are shared with other groups, suggesting research on this community is equally generalisable to others. ii As an academic work, this document promotes an understanding of the Arab American experience from an interdisciplinary point of view through focusing on the phenomenon of language in the community with emphasis placed on the AFL experience at school. Therefore, it is a broadly-framed outlook that permits, in an introductory way, a view of the richness of the Arab American experience, particularly in Dearborn, Michigan, as part of the American experience. Data were collected using two surveys, one for AFL students at a high school, and another was administered to adults in the community—in Dearborn. In addition, an action-research-based effort, individual personal interviews and focus groups were conducted with stakeholders in the community: parents/community members, teachers/school personnel and students, utilising personal involvement in understanding and analysing the data. Also, the study referred to archival and documentary evidence available in the school system. Four hypotheses regarding importance/significance and utility of Arabic were offered and tested by means of qualitative, interpretive analysis. Findings included: (1) Arab Americans valued Arabic as an emblem of their community in Dearborn, suggesting its employment as an indicator of political empowerment. (2) Conversely, in the non-Arab community Arabic was observed as a mark of the Other, and an artefact of ethnic retrenchment and rejection of assimilation. (3) Interestingly, however, development of English language competence emerged as a major concern in the community, outweighing Arabic language preservation. (4) While, language maintenance efforts in the community were observed as minimal, especially at the organisational level, and support for such programmes was marginal to nil. (5) Additionally, Arabic, while not the object of a desire to master as a medium of communication, was observed to signify a special symbol of heritage for Arab American youth in the Dearborn community, who may have rejected their parents’ ideas about learning Arabic, but had developed their own. (6) What is more, Arab American youth were observed developing a viable hybridised identity, whose mainstay is being “Arabic”, despite the dominance of English and Euro-Anglo cultural norms. (7) At the institutional level, Arabic was observed devalued in the school setting due to its association with Arabs, Islam, Arab Americans, and immigration. (8) Moreover, relations between Arab Americans and non-Arab Americans in the school system seems to have been equally impacted by this process of devaluation, furthering the cause of stigmatisation, prejudice and racism.
- Full Text:
- Date Issued: 2004
- Authors: Ayouby, Kenneth Kahtan
- Date: 2004
- Subjects: Arabic language -- Study and teaching (Higher) -- Michigan -- Dearborn , Education and language -- Michigan -- Dearborn
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:11015 , http://hdl.handle.net/10948/369 , Arabic language -- Study and teaching (Higher) -- Michigan -- Dearborn , Education and language -- Michigan -- Dearborn
- Description: This study examines the history and development of the “Arabic as a foreign language” (AFL) programme in Dearborn Public Schools (in Michigan, the United States) in its socio-cultural and political context. More specifically, this study examines the significance of Arabic to the Arab immigrant and ethnic community in Dearborn in particular, but with reference to meanings generated and associated to Arabic by non- Arabs in the same locale. Although this study addresses questions similar to research conducted on Arab Americans in light of anthropological and sociological theoretical constructs, it is, however, unique in examining education and Arabic pedagogy in Dearborn from an Arab American studies and an educational multi-cultural perspective, predicated on/and drawing from Edward Said’s critique of Orientalism, Paulo Freire’s ideas about education, and Henry Giroux’s concern with critical pedagogy. In the American mindscape, the "East" has been the theatre of the exotic, the setting of the Other from colonial times to the present. The Arab and Muslim East have been constructed to represent an opposite of American culture, values and life. Through the agency of conflation, Arab (and Muslim) Americans are accordingly lumped together with people from abroad, making for their status as permanent outsiders. Thus, if the American Self represents an ideal, the inhabitants of this oppositional world of Arabs and Islam (an Anti-world) represent an Anti-self. A source of fear and object of hate and prejudice, this Anti-self is the object of derision and anything connected with it (e.g. language, customs, religion, etc.) becomes suspect and is devalued by association. This document has two objectives: First, to present an historical account of this context, and, secondly, to shed light on how and why things that are associated with Arab Americans in Dearborn are devalued. This is achieved by addressing the developments of meanings (of actions and symbols) in their American context, and how they have shaped (and still shape) the local culture's depiction of and understanding of Arab (and Muslim) Americans. Therefore, Arab American issues of language, culture and societal interactions should be understood as constituting a stream of American life, which represent a dimension of the total American experience, past and present, that is best understood through the paradigm of American studies. Viewing this experience as a cultural whole rather than as a series of unrelated fragments (e.g. immigration waves and settlement patterns, religious and state affiliations, assimilation and preservation debates), Arab American culture and issues begin to shine through as an organic and holistic experience whose characteristics are shared with other groups, suggesting research on this community is equally generalisable to others. ii As an academic work, this document promotes an understanding of the Arab American experience from an interdisciplinary point of view through focusing on the phenomenon of language in the community with emphasis placed on the AFL experience at school. Therefore, it is a broadly-framed outlook that permits, in an introductory way, a view of the richness of the Arab American experience, particularly in Dearborn, Michigan, as part of the American experience. Data were collected using two surveys, one for AFL students at a high school, and another was administered to adults in the community—in Dearborn. In addition, an action-research-based effort, individual personal interviews and focus groups were conducted with stakeholders in the community: parents/community members, teachers/school personnel and students, utilising personal involvement in understanding and analysing the data. Also, the study referred to archival and documentary evidence available in the school system. Four hypotheses regarding importance/significance and utility of Arabic were offered and tested by means of qualitative, interpretive analysis. Findings included: (1) Arab Americans valued Arabic as an emblem of their community in Dearborn, suggesting its employment as an indicator of political empowerment. (2) Conversely, in the non-Arab community Arabic was observed as a mark of the Other, and an artefact of ethnic retrenchment and rejection of assimilation. (3) Interestingly, however, development of English language competence emerged as a major concern in the community, outweighing Arabic language preservation. (4) While, language maintenance efforts in the community were observed as minimal, especially at the organisational level, and support for such programmes was marginal to nil. (5) Additionally, Arabic, while not the object of a desire to master as a medium of communication, was observed to signify a special symbol of heritage for Arab American youth in the Dearborn community, who may have rejected their parents’ ideas about learning Arabic, but had developed their own. (6) What is more, Arab American youth were observed developing a viable hybridised identity, whose mainstay is being “Arabic”, despite the dominance of English and Euro-Anglo cultural norms. (7) At the institutional level, Arabic was observed devalued in the school setting due to its association with Arabs, Islam, Arab Americans, and immigration. (8) Moreover, relations between Arab Americans and non-Arab Americans in the school system seems to have been equally impacted by this process of devaluation, furthering the cause of stigmatisation, prejudice and racism.
- Full Text:
- Date Issued: 2004
Joint Modelling Inference for Longitudinal and Time To Event Data with Application to Biomarkers in Medical and Clinical Studies
- Authors: Azeez, Adeboye Nurudeen
- Date: 2020
- Subjects: Biochemical markers Bayesian statistical decision theory
- Language: English
- Type: Thesis , Doctoral , PhD (Biostatistics)
- Identifier: http://hdl.handle.net/10353/18476 , vital:42543
- Description: In the past couple of decades, longitudinal and survival data analysis have emerged as important and popular concepts of biostatistics and statistics for disease modelling. In recent years, these two statistics concepts have been combined to develop a joint model for longitudinal and survival data analysis. The Joint model is a simultaneous modelling application of longitudinal and survival data while taking into account a possible association between them. In this thesis, three sub-topics (Conditional score approach, estimating equation approach, and modified Cholesky decomposition approach) are utilised to model the association if the independence assumption is violated. Using the conditional score approach, the study investigated the association between longitudinal covariates and the time-to-event process to examine the within-subject measurement error that could influence estimation when the assumption of normality and mutual independence is violated. Given the assumption violation, I proposed an estimating equation approach based on the conditional score to relax parametric distributional assumptions for repeated measures of random effects. I jointly modelled the time-dependent biomarkers and event times using the Cox model with intermittent time-dependent covariates measure, in which the longitudinal model was used to characterize the biomarker underlying (unobservable) trajectory and incorporated as a latent time-dependent covariate in the survival model to predict failure times. Estimates of the parameters were obtained by a restricted maximum likelihood estimate (REML). A modified Cholesky decomposition method was used to capture the within-subject covariance for a positive definite and symmetric matrix, with the assumption that the observed data from different subjects are independent. I illustrated the proposed method by a real data set from a lung study and simulation. An extension to the joint model of longitudinal-survival data was also proposed, in which the longitudinal data has a cumulative and weighted effect on the hazard event function. Using a Bayesian parametric method, I proposed a skewed weighted probability density function to estimate the parameters. The weighted cumulative effect used enabled different longitudinal profiles to be incorporated over time in calculating the hazard ratio between the subjects. The proposed functions provide greater flexibility for modelling the association structure of different longitudinal and survival sub-model. The focus was on the association between the biomarker (serum creatinine, sCr) and the development of end-stage renal disease (ESRD). Since the effect of sCr biomarker is anticipated to be a cumulative effect, with the development of sCr biomarker over time leading to progressively higher damage of the kidney. The approach was applied a simulation for validation of the proposed method
- Full Text:
- Date Issued: 2020
- Authors: Azeez, Adeboye Nurudeen
- Date: 2020
- Subjects: Biochemical markers Bayesian statistical decision theory
- Language: English
- Type: Thesis , Doctoral , PhD (Biostatistics)
- Identifier: http://hdl.handle.net/10353/18476 , vital:42543
- Description: In the past couple of decades, longitudinal and survival data analysis have emerged as important and popular concepts of biostatistics and statistics for disease modelling. In recent years, these two statistics concepts have been combined to develop a joint model for longitudinal and survival data analysis. The Joint model is a simultaneous modelling application of longitudinal and survival data while taking into account a possible association between them. In this thesis, three sub-topics (Conditional score approach, estimating equation approach, and modified Cholesky decomposition approach) are utilised to model the association if the independence assumption is violated. Using the conditional score approach, the study investigated the association between longitudinal covariates and the time-to-event process to examine the within-subject measurement error that could influence estimation when the assumption of normality and mutual independence is violated. Given the assumption violation, I proposed an estimating equation approach based on the conditional score to relax parametric distributional assumptions for repeated measures of random effects. I jointly modelled the time-dependent biomarkers and event times using the Cox model with intermittent time-dependent covariates measure, in which the longitudinal model was used to characterize the biomarker underlying (unobservable) trajectory and incorporated as a latent time-dependent covariate in the survival model to predict failure times. Estimates of the parameters were obtained by a restricted maximum likelihood estimate (REML). A modified Cholesky decomposition method was used to capture the within-subject covariance for a positive definite and symmetric matrix, with the assumption that the observed data from different subjects are independent. I illustrated the proposed method by a real data set from a lung study and simulation. An extension to the joint model of longitudinal-survival data was also proposed, in which the longitudinal data has a cumulative and weighted effect on the hazard event function. Using a Bayesian parametric method, I proposed a skewed weighted probability density function to estimate the parameters. The weighted cumulative effect used enabled different longitudinal profiles to be incorporated over time in calculating the hazard ratio between the subjects. The proposed functions provide greater flexibility for modelling the association structure of different longitudinal and survival sub-model. The focus was on the association between the biomarker (serum creatinine, sCr) and the development of end-stage renal disease (ESRD). Since the effect of sCr biomarker is anticipated to be a cumulative effect, with the development of sCr biomarker over time leading to progressively higher damage of the kidney. The approach was applied a simulation for validation of the proposed method
- Full Text:
- Date Issued: 2020
Biological control initiatives against Lantana camara L. (Verbenaceae) in South Africa : an assessment of the present status of the programme, and an evaluation of Coelocephalapion camarae Kissinger (Coleoptera: Brentidae) and Falconia intermedia (Distant) (Heteroptera: Miridae), two new candidate natural enemies for release on the weed
- Authors: Baars, Jan-Robert
- Date: 2003
- Subjects: Lantana camara Lantana camera -- South Africa Biological pest control agents -- South Africa Beetles -- South Africa Hemiptera -- South Africa Weeds -- Biological control -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5647 , http://hdl.handle.net/10962/d1005329
- Description: Lantana camara (lantana), a thicket-forming shrub, a number of different varieties of which were introduced into South Africa as ornamental plants but which has become a serious invasive weed. Conventional control measures for lantana are expensive and ineffective and it has therefore been targeted for biological control since 1961. To date, eleven biological control agent species have become established on lantana in South Africa. However, most agents persist at low densities and only occasionally impact plant populations. Three species regularly cause significant damage, but only reach sufficiently high numbers by midsummer after populations crash during the winter. Overall, the impact of the biological control programme on the weed is negligible and this has been ascribed to the poor selection of agents for release, the accumulation of native parasitoids, differences in insect preference for different varieties of the weed and variable climatic conditions over the weed’s range. This study suggests that the importance of varietal preferences has been over-estimated. A predictive bioclimatic modelling technique showed that most of the agents established in South Africa have a wide climatic tolerance and that the redistribution and importation of new climatypes of these agents will not improve the level of control. Additional agents are required to improve the biocontrol in the temperate conditions, and also to increase damage in the sub-tropical areas where most of the agents are established and where the weed retains its leaves year round. New candidate agents that possess biological attributes that favour a high intrinsic rate of increase, a high impact per individual and that improve the synchrony between the weed and the agent in climatic conditions that promote the seasonal leaflessness of plants should receive prior consideration. A survey in Jamaica indicated that additional biological control agents are available in the region of origin but that care should be taken to prioritise the most effective agents. The various selection systems currently available in weed biocontrol produce contradictory results in the priority assigned to candidate agents and a new selection system is proposed. The biology and host range of two new candidate natural enemies, the leaf-galling weevil, Coelocephalapion camarae and the leaf-sucking mirid, Falconia intermedia were investigated for the biocontrol of lantana. The studies indicated that these have considerable biocontrol potential, in that the weevil has a wide climatic tolerance and has the potential to survive the host leaflessness typical of temperate conditions, while the mirid has a high intrinsic rate of increase, and the potential for several generations a year. Both agents caused a high level of damage to the leaves, with the weevil galling the vascular tissue in the leaf-petiole and the mirid causing chlorotic speckling of the leaves. During laboratory trials both agents accepted indigenous species in the genus Lippia. However, under multiple choice conditions these agents showed a significant and strong oviposition preference for lantana. A risk assessment and post release field trials indicated that F. intermedia is likely to attack some Lippia species in the presence of lantana, but the levels of damage are predicted to be relatively low. A possible low incidence of damage to indigenous species was considered a justifiable ‘trade-off’ for the potentially marked impact on L. camara. Preference and performance studies on the two candidate agents suggested that most of the South African lantana varieties are suitable host plants. The mirid preferred certain varieties in multiple choice experiments, but this is unlikely to affect its impact under field conditions. Permission for release was accordingly sought for both species. Finally, the challenges facing the biological control programme and the potential for improving the control of L. camara in South Africa are considered.
- Full Text:
- Date Issued: 2003
- Authors: Baars, Jan-Robert
- Date: 2003
- Subjects: Lantana camara Lantana camera -- South Africa Biological pest control agents -- South Africa Beetles -- South Africa Hemiptera -- South Africa Weeds -- Biological control -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5647 , http://hdl.handle.net/10962/d1005329
- Description: Lantana camara (lantana), a thicket-forming shrub, a number of different varieties of which were introduced into South Africa as ornamental plants but which has become a serious invasive weed. Conventional control measures for lantana are expensive and ineffective and it has therefore been targeted for biological control since 1961. To date, eleven biological control agent species have become established on lantana in South Africa. However, most agents persist at low densities and only occasionally impact plant populations. Three species regularly cause significant damage, but only reach sufficiently high numbers by midsummer after populations crash during the winter. Overall, the impact of the biological control programme on the weed is negligible and this has been ascribed to the poor selection of agents for release, the accumulation of native parasitoids, differences in insect preference for different varieties of the weed and variable climatic conditions over the weed’s range. This study suggests that the importance of varietal preferences has been over-estimated. A predictive bioclimatic modelling technique showed that most of the agents established in South Africa have a wide climatic tolerance and that the redistribution and importation of new climatypes of these agents will not improve the level of control. Additional agents are required to improve the biocontrol in the temperate conditions, and also to increase damage in the sub-tropical areas where most of the agents are established and where the weed retains its leaves year round. New candidate agents that possess biological attributes that favour a high intrinsic rate of increase, a high impact per individual and that improve the synchrony between the weed and the agent in climatic conditions that promote the seasonal leaflessness of plants should receive prior consideration. A survey in Jamaica indicated that additional biological control agents are available in the region of origin but that care should be taken to prioritise the most effective agents. The various selection systems currently available in weed biocontrol produce contradictory results in the priority assigned to candidate agents and a new selection system is proposed. The biology and host range of two new candidate natural enemies, the leaf-galling weevil, Coelocephalapion camarae and the leaf-sucking mirid, Falconia intermedia were investigated for the biocontrol of lantana. The studies indicated that these have considerable biocontrol potential, in that the weevil has a wide climatic tolerance and has the potential to survive the host leaflessness typical of temperate conditions, while the mirid has a high intrinsic rate of increase, and the potential for several generations a year. Both agents caused a high level of damage to the leaves, with the weevil galling the vascular tissue in the leaf-petiole and the mirid causing chlorotic speckling of the leaves. During laboratory trials both agents accepted indigenous species in the genus Lippia. However, under multiple choice conditions these agents showed a significant and strong oviposition preference for lantana. A risk assessment and post release field trials indicated that F. intermedia is likely to attack some Lippia species in the presence of lantana, but the levels of damage are predicted to be relatively low. A possible low incidence of damage to indigenous species was considered a justifiable ‘trade-off’ for the potentially marked impact on L. camara. Preference and performance studies on the two candidate agents suggested that most of the South African lantana varieties are suitable host plants. The mirid preferred certain varieties in multiple choice experiments, but this is unlikely to affect its impact under field conditions. Permission for release was accordingly sought for both species. Finally, the challenges facing the biological control programme and the potential for improving the control of L. camara in South Africa are considered.
- Full Text:
- Date Issued: 2003
Visual narratives of division in contemporary Palestinian art and social space
- Authors: Baasch, Rachel Mary
- Date: 2017
- Subjects: Art, Palestinian Arab , Art, Palestinian Arab -- Political aspects , Art and society -- Palestine
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/41770 , vital:25132
- Description: This study analyses artworks by contemporary Palestinian artists that respond to visual narratives of division in social space from a perspective grounded in a South African context. The state of Israel is built on Historic Palestine. Political Zionism has created an ideological narrative of division that positions people of the Jewish faith as the rightful heirs to the land on which Palestinians have lived for centuries. In order to execute their vision of an exclusively Jewish nation state, the founding pioneers of political Zionism colonised and ethnically cleansed Historic Palestine, establishing Israel in 1948. To sustain the exclusive claim to Palestinian land, Israel has divided the space and the people in it at every possible level. The greatest testament to these efforts is the Israeli apartheid wall and checkpoint security system that can be described as a monumental visual narrative of division. With each second that passes, Israel claims more Palestinian land and expands on existing fences, walls and barriers. It is no secret that the Occupied Palestinian Territories are rapidly transforming into open-air prisons. Israel has stolen the Palestinian horizon line and replaced it with a concrete wall that blocks out light, vision and optimism. Within the shadows of these conflicted, traumatised sites of division, Palestinian artists seek openings, cracks and loopholes that signal the possibility for physical and psychological transgression of these seemingly impenetrable structures of division. I have developed a creative methodology that can be understood through the metaphor of ‘looking with the skin’ as a way to identify and analyse visual narratives of division and artistic responses to sites of division in Palestinian social space. Looking with the skin combines aspects of participant observation (specifically the emphasis on engaged fieldwork) from the discipline of Anthropology with the method of visual analysis from the discipline of Art History. In my application of this method through primary fieldwork conducted within the Occupied Palestinian West Bank Territory from 2013 and 2014, I have learnt that Israel’s colonisation, military occupation and system of apartheid directly impacts the ability of Palestinian artists to make and disseminate their work as well as the choice of content within their artwork. The artworks analysed in this thesis by the artists Khaled Jarrar, Y ael Bartana, Larissa Sansour, Hasan Darahgmeh, Fareh Saleh and Emily Jacir can be positioned in relation to artworks by artists based within a South African context, namely Thando Mama, Serge Alain Nitegeka and Doung Anwar Jahangeer. In this thesis I present a combination of my own photographic documentation of sites of division with the West Bank OPT in relation to the specific artworks made by the artists mentioned above. In my analysis of the photographic documentation and the artists’ work I highlight similarities, parallels, threads and intersecting narratives that connect different artists to one another and to the sites of division they are responding to within their artistic practice. This study carves a small conceptual pathway through ideological and physical walls from South Africa to Palestine through the study of contemporary art and visual culture.
- Full Text:
- Date Issued: 2017
- Authors: Baasch, Rachel Mary
- Date: 2017
- Subjects: Art, Palestinian Arab , Art, Palestinian Arab -- Political aspects , Art and society -- Palestine
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/41770 , vital:25132
- Description: This study analyses artworks by contemporary Palestinian artists that respond to visual narratives of division in social space from a perspective grounded in a South African context. The state of Israel is built on Historic Palestine. Political Zionism has created an ideological narrative of division that positions people of the Jewish faith as the rightful heirs to the land on which Palestinians have lived for centuries. In order to execute their vision of an exclusively Jewish nation state, the founding pioneers of political Zionism colonised and ethnically cleansed Historic Palestine, establishing Israel in 1948. To sustain the exclusive claim to Palestinian land, Israel has divided the space and the people in it at every possible level. The greatest testament to these efforts is the Israeli apartheid wall and checkpoint security system that can be described as a monumental visual narrative of division. With each second that passes, Israel claims more Palestinian land and expands on existing fences, walls and barriers. It is no secret that the Occupied Palestinian Territories are rapidly transforming into open-air prisons. Israel has stolen the Palestinian horizon line and replaced it with a concrete wall that blocks out light, vision and optimism. Within the shadows of these conflicted, traumatised sites of division, Palestinian artists seek openings, cracks and loopholes that signal the possibility for physical and psychological transgression of these seemingly impenetrable structures of division. I have developed a creative methodology that can be understood through the metaphor of ‘looking with the skin’ as a way to identify and analyse visual narratives of division and artistic responses to sites of division in Palestinian social space. Looking with the skin combines aspects of participant observation (specifically the emphasis on engaged fieldwork) from the discipline of Anthropology with the method of visual analysis from the discipline of Art History. In my application of this method through primary fieldwork conducted within the Occupied Palestinian West Bank Territory from 2013 and 2014, I have learnt that Israel’s colonisation, military occupation and system of apartheid directly impacts the ability of Palestinian artists to make and disseminate their work as well as the choice of content within their artwork. The artworks analysed in this thesis by the artists Khaled Jarrar, Y ael Bartana, Larissa Sansour, Hasan Darahgmeh, Fareh Saleh and Emily Jacir can be positioned in relation to artworks by artists based within a South African context, namely Thando Mama, Serge Alain Nitegeka and Doung Anwar Jahangeer. In this thesis I present a combination of my own photographic documentation of sites of division with the West Bank OPT in relation to the specific artworks made by the artists mentioned above. In my analysis of the photographic documentation and the artists’ work I highlight similarities, parallels, threads and intersecting narratives that connect different artists to one another and to the sites of division they are responding to within their artistic practice. This study carves a small conceptual pathway through ideological and physical walls from South Africa to Palestine through the study of contemporary art and visual culture.
- Full Text:
- Date Issued: 2017
Influence of the macro-economic environment on the construction sector's contribution to the South African economy, 1984 to 2011
- Authors: Babalola, Adewumi Joseph
- Date: 2016
- Subjects: Construction industry -- Economic aspects Economic development Environmental economics
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/5618 , vital:20916
- Description: The construction sector serves as the engine of growth to the South Africa economy because of its catalytic role in the growth and development of the country. This study focuses mainly on the influence of the macro-economic environment on the contribution of the private sector to construction in the South Africa economy from 1984 to 2011. Government construction work is considered to be an injection into the economy; in this regard, state construction is regarded as public investment in the economy; and therefore, it is anti-cyclic (Keynes, 1936). The aim of this study has been to develop an econometric model for predicting the influence of the macroeconomic environment on the contribution of the private sector to the construction sector in the South Africa economy. The research design adopted in this study was an “ex-post facto” type, otherwise known as a causal-comparative design. The data were extracted from the published sources of the South African National Statistics, namely SARB, Stats SA and Quantec SA. The estimation technique used in this study was the ARDL model using quarterly data from 1984 to 2011. This is because in the construction sector, the influence of the independent variables is always felt over time – rather than all at once. The results of this study show that there is a long run causal relationship between inflation rate, interest rate, real exchange rate, GDP and gdp in the construction sector. The descriptive statistical analysis shows that there is a negative relationship between variables inflation rate and interest rate and the private sector spending in construction. However, economic growth as well as growth in the construction sector has a positive relationship with the private sector spending in construction. Likewise, the real exchange rate and labour productivity in construction have a negative relationship with the private sector’s spending in construction and they are statistically insignificant. The variance decomposition analysis show that the private sector spending in construction explains about 75 per cent of it variations, followed by inflation rate that explains 21 per cent on the average; while the remaining variations, comprising about 4 per cent, were shared among the other independent variables, such as GDP, GDP in construction, the interest rate and the real exchange rate. It was discovered that only the inflation rate does Granger-cause the private sector spending in construction. From the finding it can be concluded that inflation rate is a significant explanatory variable in explaining the variation in the dependent variable during period under review. Policy recommendations are as follows: firstly, the monetary authorities in South Africa should embark on sound policies that would bring about low prices of the construction materials. This would ensure growth and development in the construction sector; secondly, a stimulating development plan that would encourage private sector investment in properties and infrastructural development must be instituted; thirdly, an alternative policy to the present inflation targeting is recommended that would bring about low inflation, high growth, low unemployment and stable exchange rate; fourthly, the present policy on interest rate must be reviewed to allow for more participation in construction projects by the private sectors of the economy; fifthly, due to the fact that fluctuation in the crude oil prices in the international market is one of the major factors causing high inflation rate in South Africa, government must source local alternative products that would bring down prices of construction materials.
- Full Text:
- Date Issued: 2016
- Authors: Babalola, Adewumi Joseph
- Date: 2016
- Subjects: Construction industry -- Economic aspects Economic development Environmental economics
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/5618 , vital:20916
- Description: The construction sector serves as the engine of growth to the South Africa economy because of its catalytic role in the growth and development of the country. This study focuses mainly on the influence of the macro-economic environment on the contribution of the private sector to construction in the South Africa economy from 1984 to 2011. Government construction work is considered to be an injection into the economy; in this regard, state construction is regarded as public investment in the economy; and therefore, it is anti-cyclic (Keynes, 1936). The aim of this study has been to develop an econometric model for predicting the influence of the macroeconomic environment on the contribution of the private sector to the construction sector in the South Africa economy. The research design adopted in this study was an “ex-post facto” type, otherwise known as a causal-comparative design. The data were extracted from the published sources of the South African National Statistics, namely SARB, Stats SA and Quantec SA. The estimation technique used in this study was the ARDL model using quarterly data from 1984 to 2011. This is because in the construction sector, the influence of the independent variables is always felt over time – rather than all at once. The results of this study show that there is a long run causal relationship between inflation rate, interest rate, real exchange rate, GDP and gdp in the construction sector. The descriptive statistical analysis shows that there is a negative relationship between variables inflation rate and interest rate and the private sector spending in construction. However, economic growth as well as growth in the construction sector has a positive relationship with the private sector spending in construction. Likewise, the real exchange rate and labour productivity in construction have a negative relationship with the private sector’s spending in construction and they are statistically insignificant. The variance decomposition analysis show that the private sector spending in construction explains about 75 per cent of it variations, followed by inflation rate that explains 21 per cent on the average; while the remaining variations, comprising about 4 per cent, were shared among the other independent variables, such as GDP, GDP in construction, the interest rate and the real exchange rate. It was discovered that only the inflation rate does Granger-cause the private sector spending in construction. From the finding it can be concluded that inflation rate is a significant explanatory variable in explaining the variation in the dependent variable during period under review. Policy recommendations are as follows: firstly, the monetary authorities in South Africa should embark on sound policies that would bring about low prices of the construction materials. This would ensure growth and development in the construction sector; secondly, a stimulating development plan that would encourage private sector investment in properties and infrastructural development must be instituted; thirdly, an alternative policy to the present inflation targeting is recommended that would bring about low inflation, high growth, low unemployment and stable exchange rate; fourthly, the present policy on interest rate must be reviewed to allow for more participation in construction projects by the private sectors of the economy; fifthly, due to the fact that fluctuation in the crude oil prices in the international market is one of the major factors causing high inflation rate in South Africa, government must source local alternative products that would bring down prices of construction materials.
- Full Text:
- Date Issued: 2016
'Environmental policy to community action': methodology and approaches in community-based environmental education programmes in Uganda
- Authors: Babikwa, Daniel J
- Date: 2004
- Subjects: Environmental education -- Uganda -- Case studies Education and state -- Uganda Community development -- Uganda -- Case studies Sustainable development -- Uganda -- Case studies Environmental policy -- Uganda -- Case studies
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1518 , http://hdl.handle.net/10962/d1003400
- Description: This research was conducted in Luwero, a rural district in central Uganda, over a period of three years, half of which entailed fulltime engagement in a participatory action research process with VEDCO, an indigenous NGO. The study focuses on the educational processes involved in the translation of Uganda's environmental policy into action at community level. It looks at community-based education and development activities run by VEDCO among smallholder farmers. The study addressed four objectives. For the first objective I developed a conceptual framework through a review of theories informing education in general and environmental education, adult education, community education, and community development in particular. The second objective was to conduct a situational analysis to identify contextual issues related to policy implementation at community level. The third objective was to engage in a participatory action research process with the NGO in the farming community in response to the identified contextual issues, and the fourth was to explore and comment on environmental education methods used within a community context. PRA techniques, interviews, and other participatory data collection methods were used to generate the data. The study reveals contradictions that limit NGO capacity to make appropriate use of participatory education processes in implementing policy-related training at community level. Elements in the National Plan for the Modernisation of Agriculture, for example, conflicted with the principle of sustainable development underlying the policy. VEDCO itself was changing from a social-welfare-oriented organisation into a commercial enterprise pursuing economic goals, which conflicted with its social goals. The capitalist development ideology of the donor was being adopted by VEDCO, which contradicted the goals of people-centred development. This was exacerbated by VEDCO's dependency on donor funds for its activities. Contextual issues like people's history; poverty, gender and inconsistent land policies further complicated the policy implementation processes. There were also inconsistencies in the epistemological assumptions and didactic approaches evident in the implementation. The study shows that the intended emancipatory education processes are more often supplanted by technicist methodologies. Thus, it exposes the underlying historical, ideological and epistemological tensions and contradictions within the field of education, particularly in relation to the `paradigmatic' orientations (neo-classical, liberal and socially critical/emancipatory) outlined in the literature. Conclusions are made at two levels: in relation to the study goals, of examining policy implementation at community level and in terms of the study's contribution to the understanding of current education theory in the context of sustainable development among communities.
- Full Text:
- Date Issued: 2004
- Authors: Babikwa, Daniel J
- Date: 2004
- Subjects: Environmental education -- Uganda -- Case studies Education and state -- Uganda Community development -- Uganda -- Case studies Sustainable development -- Uganda -- Case studies Environmental policy -- Uganda -- Case studies
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1518 , http://hdl.handle.net/10962/d1003400
- Description: This research was conducted in Luwero, a rural district in central Uganda, over a period of three years, half of which entailed fulltime engagement in a participatory action research process with VEDCO, an indigenous NGO. The study focuses on the educational processes involved in the translation of Uganda's environmental policy into action at community level. It looks at community-based education and development activities run by VEDCO among smallholder farmers. The study addressed four objectives. For the first objective I developed a conceptual framework through a review of theories informing education in general and environmental education, adult education, community education, and community development in particular. The second objective was to conduct a situational analysis to identify contextual issues related to policy implementation at community level. The third objective was to engage in a participatory action research process with the NGO in the farming community in response to the identified contextual issues, and the fourth was to explore and comment on environmental education methods used within a community context. PRA techniques, interviews, and other participatory data collection methods were used to generate the data. The study reveals contradictions that limit NGO capacity to make appropriate use of participatory education processes in implementing policy-related training at community level. Elements in the National Plan for the Modernisation of Agriculture, for example, conflicted with the principle of sustainable development underlying the policy. VEDCO itself was changing from a social-welfare-oriented organisation into a commercial enterprise pursuing economic goals, which conflicted with its social goals. The capitalist development ideology of the donor was being adopted by VEDCO, which contradicted the goals of people-centred development. This was exacerbated by VEDCO's dependency on donor funds for its activities. Contextual issues like people's history; poverty, gender and inconsistent land policies further complicated the policy implementation processes. There were also inconsistencies in the epistemological assumptions and didactic approaches evident in the implementation. The study shows that the intended emancipatory education processes are more often supplanted by technicist methodologies. Thus, it exposes the underlying historical, ideological and epistemological tensions and contradictions within the field of education, particularly in relation to the `paradigmatic' orientations (neo-classical, liberal and socially critical/emancipatory) outlined in the literature. Conclusions are made at two levels: in relation to the study goals, of examining policy implementation at community level and in terms of the study's contribution to the understanding of current education theory in the context of sustainable development among communities.
- Full Text:
- Date Issued: 2004
Political education as a determinant of university students’ political participation in the Eastern Cape, South Africa
- Authors: Badaru, Kazeem Ajasa
- Date: 2019
- Subjects: Citizenship -- Study and teaching -- South Africa Democracy and education -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/15793 , vital:40524
- Description: Globally, there is a downward trend in youths’ political interest and participation in the learning of political education in their school curricula as a measure to combat the apparent dangers posed by the declining young citizens’ participation in the political processes.This study therefore investigated political education as a determinant of university students’ political participation in the Province of the Eastern Cape, South Africa. The study employed a mixed methods design. Using the probability sampling technique, a sample of 375 participants was randomly selected from one university in the Eastern Cape Province while semi-structured interviews were conducted among five (5) purposively selected members of the same university’s Student Representative Council (SRC) executive committee. Simple descriptive statistics such as frequency counts and percentages were used to summarize all categories of variables; while Pearson correlation statistics, Chi-square and Ordinary least square regression were used to examine the relationship between dependent and independent variables at a 95percent confidence interval. Alpha values less than 0.05 were considered to be statistically significant. Thematic content analysis was performed on the qualitative data. The quantitative analysis revealed that students’ level of political awareness was high; 98.1percent of them were aware of their rights to vote and be voted for. Students’ political judgment was positively correlated with participation in campus (r =0.182) and national politics (r = 0.030) respectively. Most of the students agreed to take part in the 2018 SRC (78.8percent) and 2019 national elections (77.9percent) respectively. Political interest was significantly correlated with participation in campus (r = 0.375) and national politics (r =0. 404). The findings from the multivariate analysis showed that political interest (<0.001), parents’ political involvement (<0.001) and year of study (<0.001) were the significant determinants of students’ participation in politics. The qualitative findings also showed that there was a positive relationship between political education and students’ participation in politics. Since political interest and family are element and agent of political education respectively, it is concluded that political education is to a large extent a determinant of university students’ political participation. It is recommended that the universities, the Department of Higher Education and Training (DHET) and other stakeholders should do a thorough review of the university education curricula and programmes to ensure that political education is adequately accommodated and taken care of in a way that would increase students’ interest, awareness and participation in politics. When this is amply done, students’ cognitive skills and capacities would be enhanced to increase their participation in the political processes in South Africa.
- Full Text:
- Date Issued: 2019
- Authors: Badaru, Kazeem Ajasa
- Date: 2019
- Subjects: Citizenship -- Study and teaching -- South Africa Democracy and education -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/15793 , vital:40524
- Description: Globally, there is a downward trend in youths’ political interest and participation in the learning of political education in their school curricula as a measure to combat the apparent dangers posed by the declining young citizens’ participation in the political processes.This study therefore investigated political education as a determinant of university students’ political participation in the Province of the Eastern Cape, South Africa. The study employed a mixed methods design. Using the probability sampling technique, a sample of 375 participants was randomly selected from one university in the Eastern Cape Province while semi-structured interviews were conducted among five (5) purposively selected members of the same university’s Student Representative Council (SRC) executive committee. Simple descriptive statistics such as frequency counts and percentages were used to summarize all categories of variables; while Pearson correlation statistics, Chi-square and Ordinary least square regression were used to examine the relationship between dependent and independent variables at a 95percent confidence interval. Alpha values less than 0.05 were considered to be statistically significant. Thematic content analysis was performed on the qualitative data. The quantitative analysis revealed that students’ level of political awareness was high; 98.1percent of them were aware of their rights to vote and be voted for. Students’ political judgment was positively correlated with participation in campus (r =0.182) and national politics (r = 0.030) respectively. Most of the students agreed to take part in the 2018 SRC (78.8percent) and 2019 national elections (77.9percent) respectively. Political interest was significantly correlated with participation in campus (r = 0.375) and national politics (r =0. 404). The findings from the multivariate analysis showed that political interest (<0.001), parents’ political involvement (<0.001) and year of study (<0.001) were the significant determinants of students’ participation in politics. The qualitative findings also showed that there was a positive relationship between political education and students’ participation in politics. Since political interest and family are element and agent of political education respectively, it is concluded that political education is to a large extent a determinant of university students’ political participation. It is recommended that the universities, the Department of Higher Education and Training (DHET) and other stakeholders should do a thorough review of the university education curricula and programmes to ensure that political education is adequately accommodated and taken care of in a way that would increase students’ interest, awareness and participation in politics. When this is amply done, students’ cognitive skills and capacities would be enhanced to increase their participation in the political processes in South Africa.
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- Date Issued: 2019