An intervention on supporting teachers’ understanding of and mediation of learning of stoichiometry in selected schools in the Zambezi Region
- Authors: Denuga, Desalu Dedayo
- Date: 2020
- Subjects: Stoichiometry -- Study and teaching (Secondary) -- Namibia , Chemistry -- Study and teaching (Secondary) -- Namibia , Participant observation -- Namibia , Constructivism (Education) -- Namibia , Pedagogical content knowledge -- Namibia , Continuing education -- Namibia , Teachers -- In-service training -- Namibia
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/103855 , vital:32315
- Description: This study has been triggered by the results on stoichiometry questions in the Directorate of Namibian Examination Assessment’s (DNEA) scripts. As highlighted in the examiners’ reports, stoichiometry is an ongoing annual problem for most students in Namibia. It is against this background that I decided to explore the possibility of an intervention in the form of continuing professional development (CPD) and collaboration workshops to improve the understanding and the mediation of learning of stoichiometry by Physical Science teachers in the Zambezi Region of Namibia. The study was underpinned by an interpretive paradigm and within this paradigm a qualitative case study approach was adopted. Since this study was in a form of an intervention, a participatory action research (PAR) approach was employed within the community of practice (CoP). I used document analysis, workshop discussions, observations and videotaped lessons, interviews (semi-structured and stimulated recall interviews) and reflections to gather data. The study was carried out at three senior secondary schools and six Physical Science teachers were involved. The study drew on the theory of constructivism as a theoretical framework, namely, Piaget’s cognitive constructivism and Vygotsky‘s social constructivism as well as Shulman’s pedagogical content knowledge (PCK). Within PCK, Mavhunga and Rollnick’s Topic Specific Pedagogical Content Knowledge (TSPCK) was used as an analytical lens (Appendix L) in this study. The findings reveal that the use of a diagnostic test on learners made the Physical Science teachers aware of the learners’ challenges and what was difficult for them to understand in stoichiometry. It also helped in their understanding of the use of prior knowledge, one of the tenets of TSPCK, to access what learners knew about stoichiometry. Further findings of the study illuminate that the Physical Science teachers’ subject matter knowledge, pedagogical content knowledge and skills had shifted as a result of their participation in the intervention workshops. The findings of this study indicate that the CoP members acquired the professional transformations which were important breakthroughs in their careers. The study thus recommends that teachers should develop effective teacher professional development activities such as study teams, exemplary lessons, cluster teaching, and peer coaching where teachers are expected to examine their assumptions and practices continuously. The implication of my study is that the developed exemplary lesson during the intervention workshops by CoP members could be useful to other Physical Science teachers in the teaching of stoichiometry in all the schools in the Zambezi Region.
- Full Text:
- Authors: Denuga, Desalu Dedayo
- Date: 2020
- Subjects: Stoichiometry -- Study and teaching (Secondary) -- Namibia , Chemistry -- Study and teaching (Secondary) -- Namibia , Participant observation -- Namibia , Constructivism (Education) -- Namibia , Pedagogical content knowledge -- Namibia , Continuing education -- Namibia , Teachers -- In-service training -- Namibia
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/103855 , vital:32315
- Description: This study has been triggered by the results on stoichiometry questions in the Directorate of Namibian Examination Assessment’s (DNEA) scripts. As highlighted in the examiners’ reports, stoichiometry is an ongoing annual problem for most students in Namibia. It is against this background that I decided to explore the possibility of an intervention in the form of continuing professional development (CPD) and collaboration workshops to improve the understanding and the mediation of learning of stoichiometry by Physical Science teachers in the Zambezi Region of Namibia. The study was underpinned by an interpretive paradigm and within this paradigm a qualitative case study approach was adopted. Since this study was in a form of an intervention, a participatory action research (PAR) approach was employed within the community of practice (CoP). I used document analysis, workshop discussions, observations and videotaped lessons, interviews (semi-structured and stimulated recall interviews) and reflections to gather data. The study was carried out at three senior secondary schools and six Physical Science teachers were involved. The study drew on the theory of constructivism as a theoretical framework, namely, Piaget’s cognitive constructivism and Vygotsky‘s social constructivism as well as Shulman’s pedagogical content knowledge (PCK). Within PCK, Mavhunga and Rollnick’s Topic Specific Pedagogical Content Knowledge (TSPCK) was used as an analytical lens (Appendix L) in this study. The findings reveal that the use of a diagnostic test on learners made the Physical Science teachers aware of the learners’ challenges and what was difficult for them to understand in stoichiometry. It also helped in their understanding of the use of prior knowledge, one of the tenets of TSPCK, to access what learners knew about stoichiometry. Further findings of the study illuminate that the Physical Science teachers’ subject matter knowledge, pedagogical content knowledge and skills had shifted as a result of their participation in the intervention workshops. The findings of this study indicate that the CoP members acquired the professional transformations which were important breakthroughs in their careers. The study thus recommends that teachers should develop effective teacher professional development activities such as study teams, exemplary lessons, cluster teaching, and peer coaching where teachers are expected to examine their assumptions and practices continuously. The implication of my study is that the developed exemplary lesson during the intervention workshops by CoP members could be useful to other Physical Science teachers in the teaching of stoichiometry in all the schools in the Zambezi Region.
- Full Text:
An investigation into the emergence of teacher leadership: a case study at an urban state senior secondary school in the Oshana Region, Namibia
- Authors: Nakafingo, Saara Lovisa
- Date: 2020
- Subjects: Educational leadership -- Namibia , Action research in education -- Namibia , Active learning -- Namibia , Continuing education -- Namibia , School management and organization -- Namibia , Cultural Historical Activity Theory
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/144645 , vital:38365
- Description: Promoting a collaborative culture and collective leadership in school has the potential to improve school performance. This may be realised through, among others, the development of teacher leadership. Teacher leadership can be referred to as the opportunities that teachers have to exercise leadership in their schools. Teacher leadership has a potential as a mechanism to bring about change in schools (Grant, 2012). Nevertheless, the concept of teacher leadership seems to be a dream, as little or no attention is being given to the phenomenon. The literature on leadership focuses mostly on those in formal leadership positions. This study thus aims to critically investigate the emergence of teacher leadership (a more informal leadership) in a case study school in order to create opportunities for teacher leadership development. As a qualitative case study adopting a formative interventionist approach, the study engaged teachers and SMT members using questionnaires, interviews and observation as data generating tools for a deeper understanding of the concept. Additionally, some documents in the school were analysed for the purpose of crystallisation. The study was guided by five research questions namely: How is the concept teacher leadership understood by teachers and SMT members in the school? What leadership roles do teachers currently fulfil in their school? What are the cultural-historical factors that enable or constrain teacher leadership in a school? How can a series of change laboratory workshops develop teacher leadership in a school? How did the change laboratory workshop sessions benefit the participants? Data was analysed adopting the teacher leadership model as a framework (Grant, 2017b) and the lens of Cultural Historical Activity Theory was also utilised in the analysis which enabled the participants to surface the systemic causes of challenges in the development of teacher leadership. The findings revealed that teachers and SMT members had an understanding of the concept teacher leadership, but their perceptions were different. Furthermore, evidence of teacher leadership existed across the various zones when teacher leaders fulfilled different roles; however, it was evident that teachers led more at the classroom level. Additionally, the study also found that certain factors enabled the practice of teacher leadership. However, it also emerged that challenges constrained the development of teacher leadership in the case study school. Some of these challenges included: the notion of top-down school management structure, time constraints and demanding teacher workloads, limited leadership knowledge, and teachers’ lack of courage and motivation to lead. For this reason, four change laboratory workshops were conducted and findings suggested that the establishment of a Teachers’ Continuous Professional Development club as a transformative agency for teacher leadership development was necessary.
- Full Text:
- Authors: Nakafingo, Saara Lovisa
- Date: 2020
- Subjects: Educational leadership -- Namibia , Action research in education -- Namibia , Active learning -- Namibia , Continuing education -- Namibia , School management and organization -- Namibia , Cultural Historical Activity Theory
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/144645 , vital:38365
- Description: Promoting a collaborative culture and collective leadership in school has the potential to improve school performance. This may be realised through, among others, the development of teacher leadership. Teacher leadership can be referred to as the opportunities that teachers have to exercise leadership in their schools. Teacher leadership has a potential as a mechanism to bring about change in schools (Grant, 2012). Nevertheless, the concept of teacher leadership seems to be a dream, as little or no attention is being given to the phenomenon. The literature on leadership focuses mostly on those in formal leadership positions. This study thus aims to critically investigate the emergence of teacher leadership (a more informal leadership) in a case study school in order to create opportunities for teacher leadership development. As a qualitative case study adopting a formative interventionist approach, the study engaged teachers and SMT members using questionnaires, interviews and observation as data generating tools for a deeper understanding of the concept. Additionally, some documents in the school were analysed for the purpose of crystallisation. The study was guided by five research questions namely: How is the concept teacher leadership understood by teachers and SMT members in the school? What leadership roles do teachers currently fulfil in their school? What are the cultural-historical factors that enable or constrain teacher leadership in a school? How can a series of change laboratory workshops develop teacher leadership in a school? How did the change laboratory workshop sessions benefit the participants? Data was analysed adopting the teacher leadership model as a framework (Grant, 2017b) and the lens of Cultural Historical Activity Theory was also utilised in the analysis which enabled the participants to surface the systemic causes of challenges in the development of teacher leadership. The findings revealed that teachers and SMT members had an understanding of the concept teacher leadership, but their perceptions were different. Furthermore, evidence of teacher leadership existed across the various zones when teacher leaders fulfilled different roles; however, it was evident that teachers led more at the classroom level. Additionally, the study also found that certain factors enabled the practice of teacher leadership. However, it also emerged that challenges constrained the development of teacher leadership in the case study school. Some of these challenges included: the notion of top-down school management structure, time constraints and demanding teacher workloads, limited leadership knowledge, and teachers’ lack of courage and motivation to lead. For this reason, four change laboratory workshops were conducted and findings suggested that the establishment of a Teachers’ Continuous Professional Development club as a transformative agency for teacher leadership development was necessary.
- Full Text:
An investigation into the fire regimes of the upper Tsitsa River catchment
- Authors: Snyman, Gareth
- Date: 2020
- Subjects: Prescribed burning -- Environmental aspects -- South Africa , Fire ecology -- South Africa , Tsitsa River catchment (South Africa) , Soil erosion -- South Africa , Grasslands -- Management -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/145256 , vital:38422
- Description: South African grasslands are rich in flora and fauna and are a dominant vegetation cover in many of the water catchment areas, while providing a multitude of services to local communities and the environment. Fires have been the primary tool used to manage grasslands for livestock production for many years. However, there is debate about how they impact and alter landscapes and there are two schools of thought throughout literature. One argument is that fires are detrimental to landscapes; altering hydrological processes by causing excess soil erosion and changing soil properties. The other opinion is that fires are beneficial to ecosystems; maintaining vegetation structure, preventing bush encroachment, cycling nutrients and allowing for new plant growth. This study focused on the effects of fire regimes on soil properties in order to better understand the role that fire plays in geomorphic processes in the upper Tsitsa River catchment. The catchment falls under two land management types- commercial and communal, with the latter being severely degraded. Fire regimes were determined using a combination of Landsat and MODIS remotely sensed data and testing was carried out on soils exposed to different Fire Return Intervals (FRI). It was found that soils that were exposed to a high fire frequency (1-2-year FRI) exhibited a significantly higher degree of water repellency (p< 0.001) and surface hardness (p< 0.001) than soils that were exposed to a low fire frequency (3-4 year FRI), which indicates increased erosion potential. However, whilst a higher fire frequency resulted in altered soil characteristics, it contributed to landscape degradation as suggested in the literature, and soils are able to return to their previous state in over a short period of time. Further investigation into factors affecting fire regimes found that geology influenced vegetation type, resulting in differences in biomass in the two land management areas. The commercially managed land supported a high biomass, which resulted in a more natural fire regime with frequent fires, whilst the communally managed land supported less biomass. Smaller fuel loads and increased landscape fragmentation through overgrazing and road networks resulted in an altered fire regime with less frequent fires. Although the communally managed land has an altered fire regime, this research suggests that fires are not influencing the severe degradation present in these areas, and this is rather a function of geology and mismanagement of land. Whilst fire and grazing management plans can be implemented to alter the modified fire regime in the communal areas back to its natural state, this would take a long time and an increase in fires would pose a threat to surrounding communities. Overall the fire regimes in the upper Tsitsa River catchment are being altered by human influence and land management type, and whilst fire frequency is negatively altering soil properties, these soils can return to their natural state. The severe land degradation present in the communally managed areas are not a function of fire frequency and rather of geology and land management.
- Full Text:
- Authors: Snyman, Gareth
- Date: 2020
- Subjects: Prescribed burning -- Environmental aspects -- South Africa , Fire ecology -- South Africa , Tsitsa River catchment (South Africa) , Soil erosion -- South Africa , Grasslands -- Management -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/145256 , vital:38422
- Description: South African grasslands are rich in flora and fauna and are a dominant vegetation cover in many of the water catchment areas, while providing a multitude of services to local communities and the environment. Fires have been the primary tool used to manage grasslands for livestock production for many years. However, there is debate about how they impact and alter landscapes and there are two schools of thought throughout literature. One argument is that fires are detrimental to landscapes; altering hydrological processes by causing excess soil erosion and changing soil properties. The other opinion is that fires are beneficial to ecosystems; maintaining vegetation structure, preventing bush encroachment, cycling nutrients and allowing for new plant growth. This study focused on the effects of fire regimes on soil properties in order to better understand the role that fire plays in geomorphic processes in the upper Tsitsa River catchment. The catchment falls under two land management types- commercial and communal, with the latter being severely degraded. Fire regimes were determined using a combination of Landsat and MODIS remotely sensed data and testing was carried out on soils exposed to different Fire Return Intervals (FRI). It was found that soils that were exposed to a high fire frequency (1-2-year FRI) exhibited a significantly higher degree of water repellency (p< 0.001) and surface hardness (p< 0.001) than soils that were exposed to a low fire frequency (3-4 year FRI), which indicates increased erosion potential. However, whilst a higher fire frequency resulted in altered soil characteristics, it contributed to landscape degradation as suggested in the literature, and soils are able to return to their previous state in over a short period of time. Further investigation into factors affecting fire regimes found that geology influenced vegetation type, resulting in differences in biomass in the two land management areas. The commercially managed land supported a high biomass, which resulted in a more natural fire regime with frequent fires, whilst the communally managed land supported less biomass. Smaller fuel loads and increased landscape fragmentation through overgrazing and road networks resulted in an altered fire regime with less frequent fires. Although the communally managed land has an altered fire regime, this research suggests that fires are not influencing the severe degradation present in these areas, and this is rather a function of geology and mismanagement of land. Whilst fire and grazing management plans can be implemented to alter the modified fire regime in the communal areas back to its natural state, this would take a long time and an increase in fires would pose a threat to surrounding communities. Overall the fire regimes in the upper Tsitsa River catchment are being altered by human influence and land management type, and whilst fire frequency is negatively altering soil properties, these soils can return to their natural state. The severe land degradation present in the communally managed areas are not a function of fire frequency and rather of geology and land management.
- Full Text:
An investigation into the knowledge a Grade one teacher uses to develop the number sense of learners with mathematics learning difficulties
- Authors: Fleming, Kirsty Ann
- Date: 2020
- Subjects: Learning disabled children -- Education -- South Africa , Mathematics -- Study and teching (Elementary) -- South Africa
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/141533 , vital:37983
- Description: Learners in South Africa continue to underperform in the international and national mathematics benchmarking tests. In the primary school, poor performance in mathematics is viewed as an indicator of limited number sense. Since the end of Apartheid, there has been a proliferation of classroom-based research that attempts to explain why learners are underperforming and find solutions to the problem. Research that seeks to explain learner underperformance attributes poor learner performance to social-economic issues, teachers’ poor content and pedagogical knowledge, the complexity of the Language of Learning and Teaching, and insufficient support for learners with Mathematics Learning Difficulties (MLD). With regards to the latter, research suggests that Foundation Phase teachers are not equipped to assist learners with MLD develop their number sense. This qualitative case study aims to investigate the knowledge that an expert Foundation Phase teacher draws on, in the process of teaching, to assist learners with MLD develop their number sense. Data generated from observations and interviews with a Grade One teacher was analysed using Rowland, Turner and Thwaites’ (2013) Knowledge Quartet. The study found that the participant Grade One teacher employed all four categories of the Knowledge Quartet when developing her learners’ number sense. In particular, she placed strong emphasis on vocabulary development as a means of circumnavigating MLD when developing number sense in a Grade One mathematics lesson. She demonstrated knowledge of: the importance of vocabulary in learning mathematics; how to develop the learners’ understanding of mathematics vocabulary (and concepts); and how to adapt her approach to support the number sense development of learners with MLD. This research has value for teacher education programmes, both pre- and in-service, as it highlights the knowledge that a Grade One teacher draws on as she develops the number sense of all her learners, including those with MLD.
- Full Text:
- Authors: Fleming, Kirsty Ann
- Date: 2020
- Subjects: Learning disabled children -- Education -- South Africa , Mathematics -- Study and teching (Elementary) -- South Africa
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/141533 , vital:37983
- Description: Learners in South Africa continue to underperform in the international and national mathematics benchmarking tests. In the primary school, poor performance in mathematics is viewed as an indicator of limited number sense. Since the end of Apartheid, there has been a proliferation of classroom-based research that attempts to explain why learners are underperforming and find solutions to the problem. Research that seeks to explain learner underperformance attributes poor learner performance to social-economic issues, teachers’ poor content and pedagogical knowledge, the complexity of the Language of Learning and Teaching, and insufficient support for learners with Mathematics Learning Difficulties (MLD). With regards to the latter, research suggests that Foundation Phase teachers are not equipped to assist learners with MLD develop their number sense. This qualitative case study aims to investigate the knowledge that an expert Foundation Phase teacher draws on, in the process of teaching, to assist learners with MLD develop their number sense. Data generated from observations and interviews with a Grade One teacher was analysed using Rowland, Turner and Thwaites’ (2013) Knowledge Quartet. The study found that the participant Grade One teacher employed all four categories of the Knowledge Quartet when developing her learners’ number sense. In particular, she placed strong emphasis on vocabulary development as a means of circumnavigating MLD when developing number sense in a Grade One mathematics lesson. She demonstrated knowledge of: the importance of vocabulary in learning mathematics; how to develop the learners’ understanding of mathematics vocabulary (and concepts); and how to adapt her approach to support the number sense development of learners with MLD. This research has value for teacher education programmes, both pre- and in-service, as it highlights the knowledge that a Grade One teacher draws on as she develops the number sense of all her learners, including those with MLD.
- Full Text:
An investigation into the nature and adequacy of tax compliance tools available to assist small businesses in the state of Oklahoma in the United States of America
- Authors: Cary, Cindi L
- Date: 2020
- Subjects: Tax administration and procedure -- United States , United States. Internal Revenue Service , Small business -- Oklahoma , Small business -- United States , Taxpayer compliance -- Oklahoma , Taxpayer compliance -- United States
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/141015 , vital:37937
- Description: This study identifies and analyses the effectiveness of the tax tools available to the small businesses that make up more than 99 per cent of all businesses in the United States and the state of Oklahoma through an extensive investigation of the small business resources offered by federal and state government agencies, higher education institutions and the professional accounting community. The study uses numerous measurements in order to acquire multiple perspectives and relies on the examination of government websites and documents, interviews, experiments, surveys, and questionnaires to determine the existing small business tax tools and their limitations. The research offers an in-depth analysis of the facts and limitations of the small business services offered by the Internal Revenue Service (IRS). The IRS is determined the largest source of small business tax tools, but limitations plague their effectiveness. Higher education is found guilty of not providing small business education in business or accounting disciplines, leaving college graduates ill-prepared to assist small businesses. Higher education is urged to implement a small business accounting curriculum that couples field experience with classroom lectures and textbooks. This study finds the accounting profession apathetic with regard to informing small businesses of accounting services and presses certified public accountants to be more involved in the education of future small business accountants. The study concludes with recommendations to reduce the small business tax burden by improving the existing small business tax tools.
- Full Text:
- Authors: Cary, Cindi L
- Date: 2020
- Subjects: Tax administration and procedure -- United States , United States. Internal Revenue Service , Small business -- Oklahoma , Small business -- United States , Taxpayer compliance -- Oklahoma , Taxpayer compliance -- United States
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/141015 , vital:37937
- Description: This study identifies and analyses the effectiveness of the tax tools available to the small businesses that make up more than 99 per cent of all businesses in the United States and the state of Oklahoma through an extensive investigation of the small business resources offered by federal and state government agencies, higher education institutions and the professional accounting community. The study uses numerous measurements in order to acquire multiple perspectives and relies on the examination of government websites and documents, interviews, experiments, surveys, and questionnaires to determine the existing small business tax tools and their limitations. The research offers an in-depth analysis of the facts and limitations of the small business services offered by the Internal Revenue Service (IRS). The IRS is determined the largest source of small business tax tools, but limitations plague their effectiveness. Higher education is found guilty of not providing small business education in business or accounting disciplines, leaving college graduates ill-prepared to assist small businesses. Higher education is urged to implement a small business accounting curriculum that couples field experience with classroom lectures and textbooks. This study finds the accounting profession apathetic with regard to informing small businesses of accounting services and presses certified public accountants to be more involved in the education of future small business accountants. The study concludes with recommendations to reduce the small business tax burden by improving the existing small business tax tools.
- Full Text:
An investigation into the readiness of open source software to build a Telco Cloud for virtualising network functions
- Authors: Chindeka, Tapiwa C
- Date: 2020
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/124320 , vital:35593
- Description: Cloud computing offers new mechanisms that change the way networks can be created and managed. The increased demand for multimedia and Internet of Things (IoT) services using the Internet Protocol is also fueling the need to look more into a networking approach that is less reliant on physical hardware components and allows new networks and network components to be created on-demand. Network Function Virtualisation (NFV) is a networking paradigm that decouples network functions from the hardware on which they run on. This offers new approaches to telecommunication providers who are looking to new ways of improving Quality of Service (QoS) in cost effective ways. Cloud technologies have given way to more specialised cloud environments such as the telco cloud. The telco cloud is a cloud environment where telecommunication services are hosted utilising NFV techniques. As the use of telecommunication standards moves towards 5G, network services will be provided in a virtualised manner in order to keep up with the demand. Open source software is a driver for innovation as it is has a collaborative culture to support it. This research investigates the readiness of open source tools to build a telco cloud that supports functions such as autoscaling and fault tolerance. Currently available open source software was explored for the different aspects involved in building a cloud from the ground up. The ETSI NFV MANO framework is also discussed as it is a widely used guiding standard for implementing NFV. Guided by the ETSI NFV MANO framework, open source software was used in an experiment to build a resilient cloud environment in which a virtualised IP Multimedia Subsystem (vIMS) network was deployed. Through this experimentation, it is evident that open source tools are mature enough to build the cloud environment and its ETSI NFV MANO compliant orchestration. However, features such as autoscaling and fault tolerance are still fairly immature and experimental.
- Full Text:
- Authors: Chindeka, Tapiwa C
- Date: 2020
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/124320 , vital:35593
- Description: Cloud computing offers new mechanisms that change the way networks can be created and managed. The increased demand for multimedia and Internet of Things (IoT) services using the Internet Protocol is also fueling the need to look more into a networking approach that is less reliant on physical hardware components and allows new networks and network components to be created on-demand. Network Function Virtualisation (NFV) is a networking paradigm that decouples network functions from the hardware on which they run on. This offers new approaches to telecommunication providers who are looking to new ways of improving Quality of Service (QoS) in cost effective ways. Cloud technologies have given way to more specialised cloud environments such as the telco cloud. The telco cloud is a cloud environment where telecommunication services are hosted utilising NFV techniques. As the use of telecommunication standards moves towards 5G, network services will be provided in a virtualised manner in order to keep up with the demand. Open source software is a driver for innovation as it is has a collaborative culture to support it. This research investigates the readiness of open source tools to build a telco cloud that supports functions such as autoscaling and fault tolerance. Currently available open source software was explored for the different aspects involved in building a cloud from the ground up. The ETSI NFV MANO framework is also discussed as it is a widely used guiding standard for implementing NFV. Guided by the ETSI NFV MANO framework, open source software was used in an experiment to build a resilient cloud environment in which a virtualised IP Multimedia Subsystem (vIMS) network was deployed. Through this experimentation, it is evident that open source tools are mature enough to build the cloud environment and its ETSI NFV MANO compliant orchestration. However, features such as autoscaling and fault tolerance are still fairly immature and experimental.
- Full Text:
An investigation into the tax consequences for individuals performing work abroad
- Authors: De Ponte, Celeste Lidia
- Date: 2020
- Subjects: South Africa. Income Tax Act, 1962 , Income tax -- Law and legislation -- South Africa , Double taxation -- South Africa , International business enterprises -- Taxation -- Law and legislation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/141235 , vital:37955
- Description: This thesis considered the income tax implications for South African tax resident individuals who render services abroad. The research included an analysis of the impact that the amendment to the section 10(1)(o)(ii) exemption has on individuals rendering services abroad and companies who send their employees abroad. In doing so, this thesis sought to highlight the key factors for consideration, for both employers and individuals. A doctrinal methodology was applied, and an analysis was carried out of relevant tax legislation, commentary of experts in the field of tax law and the relevant case law of South Africa, the United Kingdom (UK), Australia and the United States of America (US), where relevant. It was established that residency is key to determining the tax liability of a person and has an impact on the relief mechanisms that are available where double taxation arises. In addition, the amendment to section 10(1)(o)(ii) was considered. It was concluded that when rendering services abroad, both the employer and employee need to consider the tax consequences that may arise and highlights the factors which may be relevant. The thesis illustrates that, whilst the R1 million exemption alleviates the double tax consequences to a certain extent, further guidance is needed as to how the R1 million threshold will be calculated.
- Full Text:
- Authors: De Ponte, Celeste Lidia
- Date: 2020
- Subjects: South Africa. Income Tax Act, 1962 , Income tax -- Law and legislation -- South Africa , Double taxation -- South Africa , International business enterprises -- Taxation -- Law and legislation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/141235 , vital:37955
- Description: This thesis considered the income tax implications for South African tax resident individuals who render services abroad. The research included an analysis of the impact that the amendment to the section 10(1)(o)(ii) exemption has on individuals rendering services abroad and companies who send their employees abroad. In doing so, this thesis sought to highlight the key factors for consideration, for both employers and individuals. A doctrinal methodology was applied, and an analysis was carried out of relevant tax legislation, commentary of experts in the field of tax law and the relevant case law of South Africa, the United Kingdom (UK), Australia and the United States of America (US), where relevant. It was established that residency is key to determining the tax liability of a person and has an impact on the relief mechanisms that are available where double taxation arises. In addition, the amendment to section 10(1)(o)(ii) was considered. It was concluded that when rendering services abroad, both the employer and employee need to consider the tax consequences that may arise and highlights the factors which may be relevant. The thesis illustrates that, whilst the R1 million exemption alleviates the double tax consequences to a certain extent, further guidance is needed as to how the R1 million threshold will be calculated.
- Full Text:
An investigation into the use of visualisation processes as a teaching strategy to enhance number sense
- Authors: Griqua, Ronald Max
- Date: 2020
- Subjects: Mathematics -- Study and teaching -- South Africa , Mathematics -- Study and teaching -- Psychological aspects , Visualization , Number concept , RUMEP (Rhodes University Mathematics Education Project)
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/147226 , vital:38606
- Description: The literature agrees that in order to improve learning outcomes, instruction in classrooms should be improved first. Mathematics educationists therefore advocate that schools should make extensive and deep efforts to rethink their instructional programmes. Research furthermore suggests that increasingly, indicators on school performance and teaching reveal largely unacknowledged problematic teaching of mathematics in the great majority of South African schools. This research study is therefore a contribution towards rethinking the teaching strategies within mathematics classrooms. The study examined the use of visualisation processes in order to understand how these interact with the pedagogy of selected mathematics teachers when they teach number sense after participating in an intervention programme. This study argues that the effective use of visualisation processes enhanced the teaching of number sense. The research study was framed as a case study that was grounded within the interpretive paradigm. The study was located in classrooms where the participating teachers promoted active learning after taking part in an intervention programme. A constructivist theoretical underpinning was therefore adopted. At the heart of the study was the Visualisation Intervention Programme (VIP), which involved seven Rhodes University Mathematics Education Project (RUMEP) teachers within the John Taolo Gaetsewe District of the Northern Cape Province. The content of the VIP was informed by initially working with five teachers of well-resourced schools within the Northern Cape who made interesting use of visualisation processes and manipulatives to teach number sense. With the assistance of these five teachers, the VIP was then implemented by seven selected RUMEP teachers to investigate the role of visualisation processes in the teaching of number sense understandings. The study employed a mixed method approach. Qualitative data was collected through observations and interviews, while quantitative data was collected with a series of pre- and post-tests. The analysis of the findings of this research study revealed that the effective use of visualisation processes was instrumental in enhancing the teaching of number sense understandings. Furthermore, the use of visualisation processes by the selected teachers fostered independent thought and conceptual understanding of number sense topics on the part of their learners.
- Full Text:
- Authors: Griqua, Ronald Max
- Date: 2020
- Subjects: Mathematics -- Study and teaching -- South Africa , Mathematics -- Study and teaching -- Psychological aspects , Visualization , Number concept , RUMEP (Rhodes University Mathematics Education Project)
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/147226 , vital:38606
- Description: The literature agrees that in order to improve learning outcomes, instruction in classrooms should be improved first. Mathematics educationists therefore advocate that schools should make extensive and deep efforts to rethink their instructional programmes. Research furthermore suggests that increasingly, indicators on school performance and teaching reveal largely unacknowledged problematic teaching of mathematics in the great majority of South African schools. This research study is therefore a contribution towards rethinking the teaching strategies within mathematics classrooms. The study examined the use of visualisation processes in order to understand how these interact with the pedagogy of selected mathematics teachers when they teach number sense after participating in an intervention programme. This study argues that the effective use of visualisation processes enhanced the teaching of number sense. The research study was framed as a case study that was grounded within the interpretive paradigm. The study was located in classrooms where the participating teachers promoted active learning after taking part in an intervention programme. A constructivist theoretical underpinning was therefore adopted. At the heart of the study was the Visualisation Intervention Programme (VIP), which involved seven Rhodes University Mathematics Education Project (RUMEP) teachers within the John Taolo Gaetsewe District of the Northern Cape Province. The content of the VIP was informed by initially working with five teachers of well-resourced schools within the Northern Cape who made interesting use of visualisation processes and manipulatives to teach number sense. With the assistance of these five teachers, the VIP was then implemented by seven selected RUMEP teachers to investigate the role of visualisation processes in the teaching of number sense understandings. The study employed a mixed method approach. Qualitative data was collected through observations and interviews, while quantitative data was collected with a series of pre- and post-tests. The analysis of the findings of this research study revealed that the effective use of visualisation processes was instrumental in enhancing the teaching of number sense understandings. Furthermore, the use of visualisation processes by the selected teachers fostered independent thought and conceptual understanding of number sense topics on the part of their learners.
- Full Text:
An investigation of how selected Namibian grade 9 geography textbooks are reorienting school geography to education for sustainable development
- Authors: Uusiku, Naftal Amutenya
- Date: 2020
- Subjects: Geography -- Study and teaching -- Namibia , Geography -- Study and teaching -- Namibia -- Textbooks , Sustainable development -- Study and teaching -- Namibia , Environmental education -- Namibia
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/145524 , vital:38446
- Description: The World Social Science Report (UNESCO, 2013) describes environmental issues and challenges, many of which are driven by human activities. These include: changing consumption patterns, climate change, deforestation, desertification, water, population growth, poverty, food security, waste products and cultural diversity and globalization. Education for sustainable development [ESD], a vital tool for achieving the Sustainable Development Goals, requires a rethinking and reorienting of education to address sustainability (UNESCO, 2016). The International Geographical Union Commission on Geographical Education (2007, 2016) acknowledges the importance of reorienting of school geography to ESD. In Namibia, ESD has been embedded in the national curriculum. However, teachers play a critical role in reorienting school geography to ESD at the level of the classroom. They need appropriate resources to do so, the most widely used of which is the textbook. This study addresses the need for empirical research on how Namibian textbooks are reorienting geography to ESD. Using a qualitative interpretive research design, the study had the goals of understanding how selected Grade 9 textbooks are reorienting geography to ESD in what is taught (content) and how it is taught and learned (pedagogy), and how textbook authors perceive the reorienting of geography to ESD. Data were gathered through an online questionnaire of authors’ perceptions of their educational goals, important ESD content, the teaching strategies they use and the challenges they face. Document analysis was done on two causes of environmental deterioration — deforestation and population explosion in the theme Ecology — in three approved Grade 9 textbooks. The study provides evidence of how the selected textbooks are helping to reorientate school geography to the ESD content prescribed by the Namibian geography syllabus in a way that emphasizes knowing about, as opposed to critically engaging with the environmental challenges and issues at hand. With the exception of one textbook, the textbooks generally do not help to reorientate pedagogy to the transformative, change-oriented, futures-focused pedagogy advocated by the literature. Furthermore, the authors’ responses do not contain evidence that suggests their thinking is informed by contemporary perspectives on ESD or geography education. The findings provide insights for understanding how textbooks are helping to reorient Namibian school geography that may be of value to textbook authors and curriculum developers. Furthermore, it illuminates the need for theoretically informed curriculum and textbook writing workshops.
- Full Text:
- Authors: Uusiku, Naftal Amutenya
- Date: 2020
- Subjects: Geography -- Study and teaching -- Namibia , Geography -- Study and teaching -- Namibia -- Textbooks , Sustainable development -- Study and teaching -- Namibia , Environmental education -- Namibia
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/145524 , vital:38446
- Description: The World Social Science Report (UNESCO, 2013) describes environmental issues and challenges, many of which are driven by human activities. These include: changing consumption patterns, climate change, deforestation, desertification, water, population growth, poverty, food security, waste products and cultural diversity and globalization. Education for sustainable development [ESD], a vital tool for achieving the Sustainable Development Goals, requires a rethinking and reorienting of education to address sustainability (UNESCO, 2016). The International Geographical Union Commission on Geographical Education (2007, 2016) acknowledges the importance of reorienting of school geography to ESD. In Namibia, ESD has been embedded in the national curriculum. However, teachers play a critical role in reorienting school geography to ESD at the level of the classroom. They need appropriate resources to do so, the most widely used of which is the textbook. This study addresses the need for empirical research on how Namibian textbooks are reorienting geography to ESD. Using a qualitative interpretive research design, the study had the goals of understanding how selected Grade 9 textbooks are reorienting geography to ESD in what is taught (content) and how it is taught and learned (pedagogy), and how textbook authors perceive the reorienting of geography to ESD. Data were gathered through an online questionnaire of authors’ perceptions of their educational goals, important ESD content, the teaching strategies they use and the challenges they face. Document analysis was done on two causes of environmental deterioration — deforestation and population explosion in the theme Ecology — in three approved Grade 9 textbooks. The study provides evidence of how the selected textbooks are helping to reorientate school geography to the ESD content prescribed by the Namibian geography syllabus in a way that emphasizes knowing about, as opposed to critically engaging with the environmental challenges and issues at hand. With the exception of one textbook, the textbooks generally do not help to reorientate pedagogy to the transformative, change-oriented, futures-focused pedagogy advocated by the literature. Furthermore, the authors’ responses do not contain evidence that suggests their thinking is informed by contemporary perspectives on ESD or geography education. The findings provide insights for understanding how textbooks are helping to reorient Namibian school geography that may be of value to textbook authors and curriculum developers. Furthermore, it illuminates the need for theoretically informed curriculum and textbook writing workshops.
- Full Text:
An investigation of the experiences of psychotherapists regarding Ubuntu in their psychotherapy practice: an interpretative phenomenological analysis
- Authors: Qangule, Lumka Sybil
- Date: 2020
- Subjects: Ubuntu (Philosophy) , Psychotherapy -- Cross-cultural studies , Psychoanalysis and culture -- South Africa , Xhosa (African people) -- Psychology , Xhosa (African people) -- Mental health , Black people -- South Africa -- Psychology , Black people -- South Africa -- Mental health , Psychotherapists -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/146923 , vital:38577
- Description: Psychotherapy is a Eurocentric concept and practice that has migrated to South Africa with technology, as part of the general transfer of knowledge (Mkhize, 2003). It has embedded Eurocentric principles that sometimes do not easily accommodate working with Africans. It has been practised by psychotherapists of African origin with clients of African origin, but is based upon Eurocentric ideas and guidelines for practice. Many African people consider their core values to be uBuntu, rooted in a principle ‘umntu ngumntu ngabantu’ (translated as ‘a human being is a human being because of other human beings’). Some important features of uBuntu are interdependence, respect, spirituality and the primacy of communality as an approach to life. Some of the ways in which these impact on daily functioning are not foregrounded by adherence to Western principles. The use of only Eurocentric principles when working with clients of African origin may thus not lead to the desired outcomes in psychotherapy. However, these Eurocentric principles are recognised and enforced by the authoritative bodies in the field of psychology, such as the Health Professions Council of South Africa. A distinction will be made between the more inflexible ethical principles of psychology and the ideas of therapy frames. Therapy frames are not seen as being as rigid as ethical codes and they could be augmented, to be appropriate for the context, particularly in the commonly multicultural settings that are found here. Psychotherapists of African origin are torn between abiding by the ethical principles that they have been taught and practising in the way that they, together with their clients, have been socialised. Abiding by the principles as described in the codes is safe because it does not pose any threat of being sanctioned by the regulator of practice, but clients may be let down and there may be limited success with certain clients. This clash of ideas of ways of practice poses dissonance and many dilemmas among psychotherapists of African origin. Due to the nature of this study, Interpretative Phenomenological Analysis (IPA) was adopted as a suitable methodology, where eight practising amaXhosa psychotherapists were interviewed about their experiences of incorporating uBuntu in their psychotherapy practice. The raw data from initial interviews were analysed and the findings concluded that although psychotherapists were trained in Western ways of practice, they included some practices of uBuntu in their practice as well as upholding some Eurocentric principles that seemed to be helpful for their clientele. Subsequently a summary of the findings were discussed with participants in a focus group setting, where participants endorsed and expanded upon their original responses. With the above in mind, a psychotherapy model called uBuntu-Centred Psychotherapy was created, which reflects the principles and therapy frames that have been found to be useful in treating clients of African origin. This modality is more congruent with the worldviews and style of living of many South Africans, in the post-apartheid era. It embraces some Eurocentric principles that are relevant for Africans, while it is embedded in the phenomena and way of life reflected in uBuntu, a predominant mode of functioning for the group that was the focus of this study, the amaXhosa. The study ends by making recommendations for practice, as well as highlighting the need for further and more extensive research to contribute to the project of Africanising psychotherapy.
- Full Text:
- Authors: Qangule, Lumka Sybil
- Date: 2020
- Subjects: Ubuntu (Philosophy) , Psychotherapy -- Cross-cultural studies , Psychoanalysis and culture -- South Africa , Xhosa (African people) -- Psychology , Xhosa (African people) -- Mental health , Black people -- South Africa -- Psychology , Black people -- South Africa -- Mental health , Psychotherapists -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/146923 , vital:38577
- Description: Psychotherapy is a Eurocentric concept and practice that has migrated to South Africa with technology, as part of the general transfer of knowledge (Mkhize, 2003). It has embedded Eurocentric principles that sometimes do not easily accommodate working with Africans. It has been practised by psychotherapists of African origin with clients of African origin, but is based upon Eurocentric ideas and guidelines for practice. Many African people consider their core values to be uBuntu, rooted in a principle ‘umntu ngumntu ngabantu’ (translated as ‘a human being is a human being because of other human beings’). Some important features of uBuntu are interdependence, respect, spirituality and the primacy of communality as an approach to life. Some of the ways in which these impact on daily functioning are not foregrounded by adherence to Western principles. The use of only Eurocentric principles when working with clients of African origin may thus not lead to the desired outcomes in psychotherapy. However, these Eurocentric principles are recognised and enforced by the authoritative bodies in the field of psychology, such as the Health Professions Council of South Africa. A distinction will be made between the more inflexible ethical principles of psychology and the ideas of therapy frames. Therapy frames are not seen as being as rigid as ethical codes and they could be augmented, to be appropriate for the context, particularly in the commonly multicultural settings that are found here. Psychotherapists of African origin are torn between abiding by the ethical principles that they have been taught and practising in the way that they, together with their clients, have been socialised. Abiding by the principles as described in the codes is safe because it does not pose any threat of being sanctioned by the regulator of practice, but clients may be let down and there may be limited success with certain clients. This clash of ideas of ways of practice poses dissonance and many dilemmas among psychotherapists of African origin. Due to the nature of this study, Interpretative Phenomenological Analysis (IPA) was adopted as a suitable methodology, where eight practising amaXhosa psychotherapists were interviewed about their experiences of incorporating uBuntu in their psychotherapy practice. The raw data from initial interviews were analysed and the findings concluded that although psychotherapists were trained in Western ways of practice, they included some practices of uBuntu in their practice as well as upholding some Eurocentric principles that seemed to be helpful for their clientele. Subsequently a summary of the findings were discussed with participants in a focus group setting, where participants endorsed and expanded upon their original responses. With the above in mind, a psychotherapy model called uBuntu-Centred Psychotherapy was created, which reflects the principles and therapy frames that have been found to be useful in treating clients of African origin. This modality is more congruent with the worldviews and style of living of many South Africans, in the post-apartheid era. It embraces some Eurocentric principles that are relevant for Africans, while it is embedded in the phenomena and way of life reflected in uBuntu, a predominant mode of functioning for the group that was the focus of this study, the amaXhosa. The study ends by making recommendations for practice, as well as highlighting the need for further and more extensive research to contribute to the project of Africanising psychotherapy.
- Full Text:
An investigation of the influence of knowledge-production and learning processes on complex practices in a community-driven citizen science initiative: A nature conservation case study
- Authors: Alexander, Jaclyn
- Date: 2020
- Subjects: Science -- Citizen participation , Western Leopard Toad Conservation Committee , Environmental education , Frogs -- South Africa
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/138173 , vital:37603
- Description: Community-driven citizen science initiatives have become an increasingly popular tool for combating social-ecological challenges that arise within communities. Scientific protocols have been designed to strengthen and support the accuracy and reliability of data collection and information sharing; however, little is understood of the dynamic social processes that reinforce and co-ordinate such community-driven action. This qualitative case study was undertaken to identify and understand complex organisational, political and socio-cultural processes (in particular knowledge-production and learning processes) that have guided, sustained and informed complex practices in a community driven citizen science initiative. The study aimed to inform the development of a social protocol that might be transferable to other citizen science contexts. The study drew on the theory of ‘Landscapes of Practice’, which highlights how multiple communities of practice overlap, interrelate, share knowledge and cross boundaries to create potential learning across a landscape. Additionally, ideas and typologies in recent citizen science literature offered perspective on the community-driven citizen science practices. This qualitative case study focused on the bounded case of the Western Leopard Toad Conservation Committee. Specific data generation tools (interviews, observations, document analysis and diagrams) were used from multiple perspectives over time to provide rigor and depth to the data. The study demonstrated how multiple ‘nexes of practice’ co-engaged in collective knowledge creation practices, which helped to enhance ‘knowledgeability’ across the landscape. This coordinated effort, however, was sporadic and inconsistent. Recommendations are made for the development of social protocols that could assist collaborators in citizen science initiatives to scrutinise and rethink their practices and to examine both their successes and shortfalls towards their shared interest.
- Full Text:
- Authors: Alexander, Jaclyn
- Date: 2020
- Subjects: Science -- Citizen participation , Western Leopard Toad Conservation Committee , Environmental education , Frogs -- South Africa
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/138173 , vital:37603
- Description: Community-driven citizen science initiatives have become an increasingly popular tool for combating social-ecological challenges that arise within communities. Scientific protocols have been designed to strengthen and support the accuracy and reliability of data collection and information sharing; however, little is understood of the dynamic social processes that reinforce and co-ordinate such community-driven action. This qualitative case study was undertaken to identify and understand complex organisational, political and socio-cultural processes (in particular knowledge-production and learning processes) that have guided, sustained and informed complex practices in a community driven citizen science initiative. The study aimed to inform the development of a social protocol that might be transferable to other citizen science contexts. The study drew on the theory of ‘Landscapes of Practice’, which highlights how multiple communities of practice overlap, interrelate, share knowledge and cross boundaries to create potential learning across a landscape. Additionally, ideas and typologies in recent citizen science literature offered perspective on the community-driven citizen science practices. This qualitative case study focused on the bounded case of the Western Leopard Toad Conservation Committee. Specific data generation tools (interviews, observations, document analysis and diagrams) were used from multiple perspectives over time to provide rigor and depth to the data. The study demonstrated how multiple ‘nexes of practice’ co-engaged in collective knowledge creation practices, which helped to enhance ‘knowledgeability’ across the landscape. This coordinated effort, however, was sporadic and inconsistent. Recommendations are made for the development of social protocols that could assist collaborators in citizen science initiatives to scrutinise and rethink their practices and to examine both their successes and shortfalls towards their shared interest.
- Full Text:
An investigation of the internal challenges that hinder sustainability of the Furntech Nyanga incubates
- Authors: Sakuba, Siyasanga
- Date: 2020
- Subjects: Business incubators -- South Africa -- Cape Town , Business incubators -- Training of -- South Africa -- Cape Town , Entrepreneurship -- South Africa – Cape Town , Unemployment -- South Africa , Rate of return -- South Africa , Economic development -- South Africa , Training needs -- South Africa -- Cape Town , Furntech (Nyanga)
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/142830 , vital:38121
- Description: The South African unemployment rate is currently at 27.6 per cent (Statistics South Africa, 2019). In an effort to combat unemployment, the South African government has implemented various mechanisms to provide opportunities to the people and combat unemployment. One of these mechanisms is to invest in the establishment of entrepreneurship incubators while the Furntech incubator is one of the incubators established for this purpose. It is imperative that the government spending on these mechanisms is justified by a return on investment which, in this case, should be to reduce unemployment and increase the overall entrepreneurial activity. In view of Furntech, with specific reference to the Nyanga incubation centre, there is a high failure rate with very little output of sustainable enterprises from the two-year incubation period. This study seeks to investigate the internal challenges that hinder the sustainability of these entrepreneurs to either drop out before the end of the two-year incubation period or to furnish the two years without becoming sustainable entrepreneurs. This study seeks to investigate this matter by using a semi -structured interview schedule that was geared towards investigating the research problem from the view of the incubates. The findings of the study showed that Furntech can be commended in respect of the transfer of technical skills. Furntech, however, failed to support the entrepreneurs with the other business support services that are part of their services, namely the business advisory, financial support and business skills. These findings provide a guideline of where Furntech needs to improve its service offering to gain a higher output of sustainable entrepreneurs. It is important to note that even though Furntech has representation in three provinces with two incubators in the Western Cape (Cape Town and Nyanga), however, this study was limited to the Furntech Nyanga incubates.
- Full Text:
- Authors: Sakuba, Siyasanga
- Date: 2020
- Subjects: Business incubators -- South Africa -- Cape Town , Business incubators -- Training of -- South Africa -- Cape Town , Entrepreneurship -- South Africa – Cape Town , Unemployment -- South Africa , Rate of return -- South Africa , Economic development -- South Africa , Training needs -- South Africa -- Cape Town , Furntech (Nyanga)
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/142830 , vital:38121
- Description: The South African unemployment rate is currently at 27.6 per cent (Statistics South Africa, 2019). In an effort to combat unemployment, the South African government has implemented various mechanisms to provide opportunities to the people and combat unemployment. One of these mechanisms is to invest in the establishment of entrepreneurship incubators while the Furntech incubator is one of the incubators established for this purpose. It is imperative that the government spending on these mechanisms is justified by a return on investment which, in this case, should be to reduce unemployment and increase the overall entrepreneurial activity. In view of Furntech, with specific reference to the Nyanga incubation centre, there is a high failure rate with very little output of sustainable enterprises from the two-year incubation period. This study seeks to investigate the internal challenges that hinder the sustainability of these entrepreneurs to either drop out before the end of the two-year incubation period or to furnish the two years without becoming sustainable entrepreneurs. This study seeks to investigate this matter by using a semi -structured interview schedule that was geared towards investigating the research problem from the view of the incubates. The findings of the study showed that Furntech can be commended in respect of the transfer of technical skills. Furntech, however, failed to support the entrepreneurs with the other business support services that are part of their services, namely the business advisory, financial support and business skills. These findings provide a guideline of where Furntech needs to improve its service offering to gain a higher output of sustainable entrepreneurs. It is important to note that even though Furntech has representation in three provinces with two incubators in the Western Cape (Cape Town and Nyanga), however, this study was limited to the Furntech Nyanga incubates.
- Full Text:
An unsung dialogue: music, society and the history of The Flames
- Authors: Park, Duncan Keith
- Date: 2020
- Subjects: The Flames (Musical group) , Fataar, Steve , Durban (South Africa) -- History , Durban (South Africa) -- Race relations , Musical groups -- South Africa , Music -- Social aspects -- South Africa , Music -- Social aspects -- South Africa -- Durban , South Africa -- Politics and government -- 1961-1978
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/169632 , vital:41780
- Description: This research aims to examine the relationship between music and social conditions within the context of apartheid . The focus area is the city of Durban, specifically 1960-1970. A case study of the multi-racial Durban-based band, The Flames 1963–1972) will be used to rigorously assess the extent to which social conditions and music can affect each other in both directions. This will also be the first coherent and historical narrative of the band, The Flames. As such, the thesis aims to make an original contribution to this field of music history, while it will provide the very first academic discussion of The Flames. South Africa during apartheid, with its racialised legislation provides an ideal context to scrutinize the effects (both potential and real) of music on social conditions. The Flames provide a particularly relevant case point; being a collective of “mixed-race” individuals classified as Coloured performing for a multi-racial fan- base. This means that at their concerts, audience members would have frequently been from a variety of different racial backgrounds. This would have been in direct contravention to the National Party‟s (NP) Separate Amenities Act as well as the policy of “separate development”, the cornerstone of apartheid. The thesis will firstly contextualise the research within the broader, global historical context, as well as in the existing theoretical literature which focuses on the relationship between music, politics and society. Firstly, this will entail a brief historical account of popular music around the world during the twentieth century. Through this we will observe both the ways in which the development and popularisation of various forms of popular music came to be shaped in a particular way, as well as the ways in which the public received this music. This will include an examination of positive responses to certain kinds of popular music which resonated and became popular with various sectors of society. Conversely, it will also closely examine the backlashes against these musical forms, and attempt to identify why certain sectors of the public were deeply opposed to particular kinds of popular music which may have been perceived to embody certain values and meanings. This will be conducted by studying various forms of popular music from the turn of the twentieth century into the early 1970s with a cross-cultural, global perspective, examining particular historical instances and existing theories relating to these instances. Chapter one will then shift from a global perspective and will situate the research within the South African musical context specifically. This will include an account of the development of South African popular music through the twentieth century in relation to the country's politics. Through examining this relationship, the dialogue between historical case studies and theoretical literature will continue, in which existing theories relating to the relationship between music, politics and society will be discussed. This theoretical literature will be made use of in the final section of the paper in order to make sense of The Flames and their role in South African history. The second section of this thesis will focus on the socio-historical context of the city of Durban under apartheid. The author will contextualise the research through a narrative historical retelling of Durban‟s social history, focusing on both political and social public mobilisation and the role of cultural spaces and practices within these his torical moments and their relevant structures. Attention will be paid to the development of segregation and apartheid within Durban specifically, while racial relations will also be fo cused upon. This will provide the reader with the necessary background required in order to meaningfully understand how the band The Flames came into existence, became popular, and whether or not they had any meaningful effect on their historical context. The section on Durban's history will be followed by a brief account of Durban's Coloured community's history, as well as a discussion around Coloured identity more broadly within the South African context. This will be vital to the research due to the fact that the musicians of The Flames were classified as Coloured under apartheid, and such an historical background will be critical to understanding the social, political and economic context of the band. Finally, the thesis will end with the written history of The Flame . This final section will provide an account of The Flames' history in which the band will be made sense of within the context of Durban during apartheid, as well as within the context of South African music, and the globalised context of popular music. By situating the band within these three contexts, we can truly assess both how they were shaped by their contexts, and whether they had any effect on these contexts of which they were a part. In this section those existing theories around the relationship between music, politics and society will be discussed and assessed in order to determine how useful a framework they may be for understanding popular music in certain historical contexts. In this way, the research aims to make a meaningful contribution to the study of music and its socio-political role throughout history, as well as to the broader understanding of Durban's history. Specifically, the role of music in Durban's history is being examined, and the researcher hopes that this work can begin to open up new discussions around the importance of studying music in Durban, and South Africa's history. Additionally, this thesis will open up a new area of research into a band which, until this point, has not been engaged with in the field of music history whatsoever. .
- Full Text:
- Authors: Park, Duncan Keith
- Date: 2020
- Subjects: The Flames (Musical group) , Fataar, Steve , Durban (South Africa) -- History , Durban (South Africa) -- Race relations , Musical groups -- South Africa , Music -- Social aspects -- South Africa , Music -- Social aspects -- South Africa -- Durban , South Africa -- Politics and government -- 1961-1978
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/169632 , vital:41780
- Description: This research aims to examine the relationship between music and social conditions within the context of apartheid . The focus area is the city of Durban, specifically 1960-1970. A case study of the multi-racial Durban-based band, The Flames 1963–1972) will be used to rigorously assess the extent to which social conditions and music can affect each other in both directions. This will also be the first coherent and historical narrative of the band, The Flames. As such, the thesis aims to make an original contribution to this field of music history, while it will provide the very first academic discussion of The Flames. South Africa during apartheid, with its racialised legislation provides an ideal context to scrutinize the effects (both potential and real) of music on social conditions. The Flames provide a particularly relevant case point; being a collective of “mixed-race” individuals classified as Coloured performing for a multi-racial fan- base. This means that at their concerts, audience members would have frequently been from a variety of different racial backgrounds. This would have been in direct contravention to the National Party‟s (NP) Separate Amenities Act as well as the policy of “separate development”, the cornerstone of apartheid. The thesis will firstly contextualise the research within the broader, global historical context, as well as in the existing theoretical literature which focuses on the relationship between music, politics and society. Firstly, this will entail a brief historical account of popular music around the world during the twentieth century. Through this we will observe both the ways in which the development and popularisation of various forms of popular music came to be shaped in a particular way, as well as the ways in which the public received this music. This will include an examination of positive responses to certain kinds of popular music which resonated and became popular with various sectors of society. Conversely, it will also closely examine the backlashes against these musical forms, and attempt to identify why certain sectors of the public were deeply opposed to particular kinds of popular music which may have been perceived to embody certain values and meanings. This will be conducted by studying various forms of popular music from the turn of the twentieth century into the early 1970s with a cross-cultural, global perspective, examining particular historical instances and existing theories relating to these instances. Chapter one will then shift from a global perspective and will situate the research within the South African musical context specifically. This will include an account of the development of South African popular music through the twentieth century in relation to the country's politics. Through examining this relationship, the dialogue between historical case studies and theoretical literature will continue, in which existing theories relating to the relationship between music, politics and society will be discussed. This theoretical literature will be made use of in the final section of the paper in order to make sense of The Flames and their role in South African history. The second section of this thesis will focus on the socio-historical context of the city of Durban under apartheid. The author will contextualise the research through a narrative historical retelling of Durban‟s social history, focusing on both political and social public mobilisation and the role of cultural spaces and practices within these his torical moments and their relevant structures. Attention will be paid to the development of segregation and apartheid within Durban specifically, while racial relations will also be fo cused upon. This will provide the reader with the necessary background required in order to meaningfully understand how the band The Flames came into existence, became popular, and whether or not they had any meaningful effect on their historical context. The section on Durban's history will be followed by a brief account of Durban's Coloured community's history, as well as a discussion around Coloured identity more broadly within the South African context. This will be vital to the research due to the fact that the musicians of The Flames were classified as Coloured under apartheid, and such an historical background will be critical to understanding the social, political and economic context of the band. Finally, the thesis will end with the written history of The Flame . This final section will provide an account of The Flames' history in which the band will be made sense of within the context of Durban during apartheid, as well as within the context of South African music, and the globalised context of popular music. By situating the band within these three contexts, we can truly assess both how they were shaped by their contexts, and whether they had any effect on these contexts of which they were a part. In this section those existing theories around the relationship between music, politics and society will be discussed and assessed in order to determine how useful a framework they may be for understanding popular music in certain historical contexts. In this way, the research aims to make a meaningful contribution to the study of music and its socio-political role throughout history, as well as to the broader understanding of Durban's history. Specifically, the role of music in Durban's history is being examined, and the researcher hopes that this work can begin to open up new discussions around the importance of studying music in Durban, and South Africa's history. Additionally, this thesis will open up a new area of research into a band which, until this point, has not been engaged with in the field of music history whatsoever. .
- Full Text:
Analysing emergent time within an isolated Universe through the application of interactions in the conditional probability approach
- Authors: Bryan, Kate Louise Halse
- Date: 2020
- Subjects: Space and time , Quantum gravity , Quantum theory , Relativity (Physics)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/146676 , vital:38547
- Description: Time remains a frequently discussed issue in physics and philosophy. One interpretation of growing popularity is the ‘timeless’ view which states that our experience of time is only an illusion. The isolated Universe model, provided by the Wheeler-DeWitt equation, supports this interpretation by describing time using clocks in the conditional probability interpretation (CPI). However, the CPI customarily dismisses interaction effects as negligible creating a potential blind spot which overlooks the potential influence of interaction effects. Accounting for interactions opens up a new avenue of analysis and a potential challenge to the interpretation of time. In aid of our assessment of the impact interaction effects have on the CPI, we present rudimentary definitions of time and its associated concepts. Defined in a minimalist manner, time is argued to require a postulate of causality as a means of accounting for temporal ordering in physical theories. Several of these theories are discussed here in terms of their respective approaches to time and, despite their differences, there are indications that the accounts of time are unified in a more fundamental theory. An analytic analysis of the CPI, incorporating two different clock choices, and a qualitative analysis both confirm that interactions have a necessary role within the CPI. The consequence of removing interactions is a maximised uncertainty in any measurement of the clock and a restriction to a two-state system, as indicated by the results of the toy models and qualitative argument respectively. The philosophical implication is that we are not restricted to the timeless view since including interactions as agents of causal interventions between systems provides an account of time as a real phenomenon. This result highlights the reliance on a postulate of causality which forms a pressing problem in explaining our experience of time.
- Full Text:
- Authors: Bryan, Kate Louise Halse
- Date: 2020
- Subjects: Space and time , Quantum gravity , Quantum theory , Relativity (Physics)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/146676 , vital:38547
- Description: Time remains a frequently discussed issue in physics and philosophy. One interpretation of growing popularity is the ‘timeless’ view which states that our experience of time is only an illusion. The isolated Universe model, provided by the Wheeler-DeWitt equation, supports this interpretation by describing time using clocks in the conditional probability interpretation (CPI). However, the CPI customarily dismisses interaction effects as negligible creating a potential blind spot which overlooks the potential influence of interaction effects. Accounting for interactions opens up a new avenue of analysis and a potential challenge to the interpretation of time. In aid of our assessment of the impact interaction effects have on the CPI, we present rudimentary definitions of time and its associated concepts. Defined in a minimalist manner, time is argued to require a postulate of causality as a means of accounting for temporal ordering in physical theories. Several of these theories are discussed here in terms of their respective approaches to time and, despite their differences, there are indications that the accounts of time are unified in a more fundamental theory. An analytic analysis of the CPI, incorporating two different clock choices, and a qualitative analysis both confirm that interactions have a necessary role within the CPI. The consequence of removing interactions is a maximised uncertainty in any measurement of the clock and a restriction to a two-state system, as indicated by the results of the toy models and qualitative argument respectively. The philosophical implication is that we are not restricted to the timeless view since including interactions as agents of causal interventions between systems provides an account of time as a real phenomenon. This result highlights the reliance on a postulate of causality which forms a pressing problem in explaining our experience of time.
- Full Text:
Analysis of bacterial Mur amide ligase enzymes for the identification of inhibitory compounds by in silico methods
- Chamboko, Chiratidzo Respina
- Authors: Chamboko, Chiratidzo Respina
- Date: 2020
- Subjects: Mur amide ligases , Ligases , Ligand binding (Biochemistry) , Antibacterial agents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/163430 , vital:41036
- Description: An increased emergence of resistant pathogenic bacterial strains over the years has resulted in many people dying of untreatable infections. This has become one of the most critical global public health problems, as resistant strains are complicating treatment of infectious diseases, increasing human morbidity, mortality, and health care costs. A very limited amount of effective antibiotics is currently available, but the development of novel classes of antibacterial agents is becoming a priority. Mur amide ligases are enzymes that have been identified as potentially good targets for antibiotics, as they are uniquely found in bacteria. They are responsible for the formation of peptide bonds in a growing peptidoglycan structure for bacterial cell walls. The current work presented here focused on characterizing these Mur amide ligase enzymes and obtaining inhibitory compounds that could potentially be of use in drug discovery of antibacterial agents. To do this, multiple sequence alignment, motif analysis and phylogenetic tree constructions were carried out, followed by docking studies and molecular dynamic simulations. Prior to docking, homology modelling of missing residues in the MurF structure (PDB 1GG4) was performed. Characterization results revealed the Mur amide ligase enzymes contained defined conservation in limited regions, that ultimately mapped towards the central domain responsible for ATP binding (presence of a conserved GKT motif). Further analysis of results further unraveled the unique patterns observed within each group of the family of enzymes. As a result of these findings, docking studies were carried out on each Mur amide ligase structure. At most, two ligands were identified to be sufficiently inhibiting each Mur amide ligase. The ligands obtained were SANC00574 and SANC00575 for MurC, SANC00290 and SANC00438 for MurD, SANC00290 and SANC00525 for MurE and SANC00290 and SANC00434 for MurF. The two best ligands identified for each enzyme had docked in the active site of their respective proteins, passed Lipinski’s rule of five and had substantially low binding energies. Molecular dynamic simulations were then performed to analyze the behavior of the proteins and protein-ligand complexes, to confirm the lead compounds as good inhibitors of the Mur amide ligases. In the case of MurC, MurD and MurE complexes, the identified ligands clearly impacted the behavior of the protein, as the ligand bound proteins became more compact and stable, while flexibility decreased. There was however an opposite effect on MurF complexes, that resulted in identified inhibitors being discarded. As a potential next step, in vivo and in vitro experiments can be performed with identified ligands from this research, to further support the information presented.
- Full Text:
- Authors: Chamboko, Chiratidzo Respina
- Date: 2020
- Subjects: Mur amide ligases , Ligases , Ligand binding (Biochemistry) , Antibacterial agents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/163430 , vital:41036
- Description: An increased emergence of resistant pathogenic bacterial strains over the years has resulted in many people dying of untreatable infections. This has become one of the most critical global public health problems, as resistant strains are complicating treatment of infectious diseases, increasing human morbidity, mortality, and health care costs. A very limited amount of effective antibiotics is currently available, but the development of novel classes of antibacterial agents is becoming a priority. Mur amide ligases are enzymes that have been identified as potentially good targets for antibiotics, as they are uniquely found in bacteria. They are responsible for the formation of peptide bonds in a growing peptidoglycan structure for bacterial cell walls. The current work presented here focused on characterizing these Mur amide ligase enzymes and obtaining inhibitory compounds that could potentially be of use in drug discovery of antibacterial agents. To do this, multiple sequence alignment, motif analysis and phylogenetic tree constructions were carried out, followed by docking studies and molecular dynamic simulations. Prior to docking, homology modelling of missing residues in the MurF structure (PDB 1GG4) was performed. Characterization results revealed the Mur amide ligase enzymes contained defined conservation in limited regions, that ultimately mapped towards the central domain responsible for ATP binding (presence of a conserved GKT motif). Further analysis of results further unraveled the unique patterns observed within each group of the family of enzymes. As a result of these findings, docking studies were carried out on each Mur amide ligase structure. At most, two ligands were identified to be sufficiently inhibiting each Mur amide ligase. The ligands obtained were SANC00574 and SANC00575 for MurC, SANC00290 and SANC00438 for MurD, SANC00290 and SANC00525 for MurE and SANC00290 and SANC00434 for MurF. The two best ligands identified for each enzyme had docked in the active site of their respective proteins, passed Lipinski’s rule of five and had substantially low binding energies. Molecular dynamic simulations were then performed to analyze the behavior of the proteins and protein-ligand complexes, to confirm the lead compounds as good inhibitors of the Mur amide ligases. In the case of MurC, MurD and MurE complexes, the identified ligands clearly impacted the behavior of the protein, as the ligand bound proteins became more compact and stable, while flexibility decreased. There was however an opposite effect on MurF complexes, that resulted in identified inhibitors being discarded. As a potential next step, in vivo and in vitro experiments can be performed with identified ligands from this research, to further support the information presented.
- Full Text:
Analysis of bacterial Mur amide ligase enzymes for the identification of inhibitory compounds by in silico methods
- Chamboko, Chiratidzo Respina
- Authors: Chamboko, Chiratidzo Respina
- Date: 2020
- Subjects: Pathogenic microorganisms -- Analysis , Drug resistance in microorganisms , Microorganisms -- Effect of drugs on , Antibiotics -- Effectiveness , Pathogenic bacteria , Drug tolerance , Enzymes -- Analysis , Peptide antibiotics
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/161911 , vital:40690
- Description: An increased emergence of resistant pathogenic bacterial strains over the years has resulted in many people dying of untreatable infections. This has become one of the most critical global public health problems, as resistant strains are complicating treatment of infectious diseases, increasing human morbidity, mortality, and health care costs. A very limited amount of effective antibiotics is currently available, but the development of novel classes of antibacterial agents is becoming a priority. Mur amide ligases are enzymes that have been identified as potentially good targets for antibiotics, as they are uniquely found in bacteria. They are responsible for the formation of peptide bonds in a growing peptidoglycan structure for bacterial cell walls. The current work presented here focused on characterizing these Mur amide ligase enzymes and obtaining inhibitory compounds that could potentially be of use in drug discovery of antibacterial agents. To do this, multiple sequence alignment, motif analysis and phylogenetic tree constructions were carried out, followed by docking studies and molecular dynamic simulations. Prior to docking, homology modelling of missing residues in the MurF structure (PDB 1GG4) was performed. Characterization results revealed the Mur amide ligase enzymes contained defined conservation in limited regions, that ultimately mapped towards the central domain responsible for ATP binding (presence of a conserved GKT motif). Further analysis of results further unraveled the unique patterns observed within each group of the family of enzymes. As a result of these findings, docking studies were carried out on each Mur amide ligase structure. At most, two ligands were identified to be sufficiently inhibiting each Mur amide ligase. The ligands obtained were SANC00574 and SANC00575 for MurC, SANC00290 and SANC00438 for MurD, SANC00290 and SANC00525 for MurE and SANC00290 and SANC00434 for MurF. The two best ligands identified for each enzyme had docked in the active site of their respective proteins, passed Lipinski’s rule of five and had substantially low binding energies. Molecular dynamic simulations were then performed to analyze the behavior of the proteins and protein-ligand complexes, to confirm the lead compounds as good inhibitors of the Mur amide ligases. In the case of MurC, MurD and MurE complexes, the identified ligands clearly impacted the behavior of the protein, as the ligand bound proteins became more compact and stable, while flexibility decreased. There was however an opposite effect on MurF complexes, that resulted in identified inhibitors being discarded. As a potential next step, in vivo and in vitro experiments can be performed with identified ligands from this research, to further support the information presented.
- Full Text:
- Authors: Chamboko, Chiratidzo Respina
- Date: 2020
- Subjects: Pathogenic microorganisms -- Analysis , Drug resistance in microorganisms , Microorganisms -- Effect of drugs on , Antibiotics -- Effectiveness , Pathogenic bacteria , Drug tolerance , Enzymes -- Analysis , Peptide antibiotics
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/161911 , vital:40690
- Description: An increased emergence of resistant pathogenic bacterial strains over the years has resulted in many people dying of untreatable infections. This has become one of the most critical global public health problems, as resistant strains are complicating treatment of infectious diseases, increasing human morbidity, mortality, and health care costs. A very limited amount of effective antibiotics is currently available, but the development of novel classes of antibacterial agents is becoming a priority. Mur amide ligases are enzymes that have been identified as potentially good targets for antibiotics, as they are uniquely found in bacteria. They are responsible for the formation of peptide bonds in a growing peptidoglycan structure for bacterial cell walls. The current work presented here focused on characterizing these Mur amide ligase enzymes and obtaining inhibitory compounds that could potentially be of use in drug discovery of antibacterial agents. To do this, multiple sequence alignment, motif analysis and phylogenetic tree constructions were carried out, followed by docking studies and molecular dynamic simulations. Prior to docking, homology modelling of missing residues in the MurF structure (PDB 1GG4) was performed. Characterization results revealed the Mur amide ligase enzymes contained defined conservation in limited regions, that ultimately mapped towards the central domain responsible for ATP binding (presence of a conserved GKT motif). Further analysis of results further unraveled the unique patterns observed within each group of the family of enzymes. As a result of these findings, docking studies were carried out on each Mur amide ligase structure. At most, two ligands were identified to be sufficiently inhibiting each Mur amide ligase. The ligands obtained were SANC00574 and SANC00575 for MurC, SANC00290 and SANC00438 for MurD, SANC00290 and SANC00525 for MurE and SANC00290 and SANC00434 for MurF. The two best ligands identified for each enzyme had docked in the active site of their respective proteins, passed Lipinski’s rule of five and had substantially low binding energies. Molecular dynamic simulations were then performed to analyze the behavior of the proteins and protein-ligand complexes, to confirm the lead compounds as good inhibitors of the Mur amide ligases. In the case of MurC, MurD and MurE complexes, the identified ligands clearly impacted the behavior of the protein, as the ligand bound proteins became more compact and stable, while flexibility decreased. There was however an opposite effect on MurF complexes, that resulted in identified inhibitors being discarded. As a potential next step, in vivo and in vitro experiments can be performed with identified ligands from this research, to further support the information presented.
- Full Text:
Analysis of the relationship between changes in macroeconomic variables and various sector price indices of JSE
- Mapanda, Tungamirai Chisvuvo
- Authors: Mapanda, Tungamirai Chisvuvo
- Date: 2020
- Subjects: Johannesburg Stock Exchange , Stock price indexes -- South Africa , Interest rates -- South Africa
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/147445 , vital:38637
- Description: Purpose- The purpose of this paper is to analyse the relationship between changes in domestic macroeconomic variables and various indices of the JSE during the full time period, June 1995 to December 2018 and the sub-periods, June 1995 to June 2007 and July 2007 to December 2018. Design/ methodology/ approach- The paper employs the Autoregressive Distributed Lag (ARDL) model approach to cointegration using monthly data from June 1995 to December 2018. Findings- In terms of the long run, the results show that the coincident indicator measure of domestic economic activity is positively and significantly related to the various JSE indices for all study periods. In terms of inflation, the results show no relationship between inflation rate and the various indices for both whole period and June 1995 to June 2007 sub period. However for the July 2007 to December 2018 sub period, JSE All Share Index and JSE Top 40 Index are negatively related. For the real effective exchange rate, only the Consumer Services Index is positively related to the exchange rate in terms of June 1995 to June 2007 sub period. However, JSE All Share Index and JSE Top 40 Index are negatively related to the exchange rate in all study periods. In terms of the short term interest rate, for the whole period, JSE All Share Index, JSE Top 40 Index, Health Care Index and Telecommunications Index are negatively related to interest rate. In terms of the June 1995 to June 2007 sub period, JSE All Share Index and Industrials Index are negatively related to the short term interest rate. For the July 2007 to December 2018 sub period, Telecommunications Index and Technology Index are negatively related. In terms of the short run, the coincident indicator is positively and significantly related to the various JSE indices for all study periods. Inflation is not significantly related to any index in the whole period. In terms of the June 1995 to June 2007 sub period, Industrials Index and Financials Index are positively related to inflation and in the July 2007 to December 2018 sub period, Consumer Goods Index, Health Index and Consumer Services Index are negatively related to the inflation rate. The real effective exchange rate is positively and significantly related to the various JSE indices in the different study periods. In terms of the short term interest rate, for the whole period and the June 1995 to June 2007 sub period only the Technology Index is not significantly and negatively related to the short term interest rate, but for the July 2007 to December 2018 sub period, Top 40 Index, Telecommunications Index and Technology Index are positively related to the interest rate. Only the Financial Index is negatively related to short term interest rates during this sub period. Research Limitations- Not a lot literature was found on the relationship between macroeconomic variables and the various sector indices of the JSE. Most previous work, in the South African context focused just on the JSE All Share Index. Practical Implications- The findings can help investors diversify their portfolios into indices that benefit from expected changes in macroeconomic variables, such as recessions, rising interest rates, rising inflation or a weakening exchange rate. Alternatively, they can hedge themselves against the negative implications of such macroeconomic changes on portfolio performance. In addition, the findings are important for the monetary authorities to better understand the implications of their policy changes on financial markets.
- Full Text:
- Authors: Mapanda, Tungamirai Chisvuvo
- Date: 2020
- Subjects: Johannesburg Stock Exchange , Stock price indexes -- South Africa , Interest rates -- South Africa
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/147445 , vital:38637
- Description: Purpose- The purpose of this paper is to analyse the relationship between changes in domestic macroeconomic variables and various indices of the JSE during the full time period, June 1995 to December 2018 and the sub-periods, June 1995 to June 2007 and July 2007 to December 2018. Design/ methodology/ approach- The paper employs the Autoregressive Distributed Lag (ARDL) model approach to cointegration using monthly data from June 1995 to December 2018. Findings- In terms of the long run, the results show that the coincident indicator measure of domestic economic activity is positively and significantly related to the various JSE indices for all study periods. In terms of inflation, the results show no relationship between inflation rate and the various indices for both whole period and June 1995 to June 2007 sub period. However for the July 2007 to December 2018 sub period, JSE All Share Index and JSE Top 40 Index are negatively related. For the real effective exchange rate, only the Consumer Services Index is positively related to the exchange rate in terms of June 1995 to June 2007 sub period. However, JSE All Share Index and JSE Top 40 Index are negatively related to the exchange rate in all study periods. In terms of the short term interest rate, for the whole period, JSE All Share Index, JSE Top 40 Index, Health Care Index and Telecommunications Index are negatively related to interest rate. In terms of the June 1995 to June 2007 sub period, JSE All Share Index and Industrials Index are negatively related to the short term interest rate. For the July 2007 to December 2018 sub period, Telecommunications Index and Technology Index are negatively related. In terms of the short run, the coincident indicator is positively and significantly related to the various JSE indices for all study periods. Inflation is not significantly related to any index in the whole period. In terms of the June 1995 to June 2007 sub period, Industrials Index and Financials Index are positively related to inflation and in the July 2007 to December 2018 sub period, Consumer Goods Index, Health Index and Consumer Services Index are negatively related to the inflation rate. The real effective exchange rate is positively and significantly related to the various JSE indices in the different study periods. In terms of the short term interest rate, for the whole period and the June 1995 to June 2007 sub period only the Technology Index is not significantly and negatively related to the short term interest rate, but for the July 2007 to December 2018 sub period, Top 40 Index, Telecommunications Index and Technology Index are positively related to the interest rate. Only the Financial Index is negatively related to short term interest rates during this sub period. Research Limitations- Not a lot literature was found on the relationship between macroeconomic variables and the various sector indices of the JSE. Most previous work, in the South African context focused just on the JSE All Share Index. Practical Implications- The findings can help investors diversify their portfolios into indices that benefit from expected changes in macroeconomic variables, such as recessions, rising interest rates, rising inflation or a weakening exchange rate. Alternatively, they can hedge themselves against the negative implications of such macroeconomic changes on portfolio performance. In addition, the findings are important for the monetary authorities to better understand the implications of their policy changes on financial markets.
- Full Text:
Application of machine learning, molecular modelling and structural data mining against antiretroviral drug resistance in HIV-1
- Sheik Amamuddy, Olivier Serge André
- Authors: Sheik Amamuddy, Olivier Serge André
- Date: 2020
- Subjects: Machine learning , Molecules -- Models , Data mining , Neural networks (Computer science) , Antiretroviral agents , Protease inhibitors , Drug resistance , Multidrug resistance , Molecular dynamics , Renin-angiotensin system , HIV (Viruses) -- South Africa , HIV (Viruses) -- Social aspects -- South Africa , South African Natural Compounds Database
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/115964 , vital:34282
- Description: Millions are affected with the Human Immunodeficiency Virus (HIV) world wide, even though the death toll is on the decline. Antiretrovirals (ARVs), more specifically protease inhibitors have shown tremendous success since their introduction into therapy since the mid 1990’s by slowing down progression to the Acquired Immune Deficiency Syndrome (AIDS). However, Drug Resistance Mutations (DRMs) are constantly selected for due to viral adaptation, making drugs less effective over time. The current challenge is to manage the infection optimally with a limited set of drugs, with differing associated levels of toxicities in the face of a virus that (1) exists as a quasispecies, (2) may transmit acquired DRMs to drug-naive individuals and (3) that can manifest class-wide resistance due to similarities in design. The presence of latent reservoirs, unawareness of infection status, education and various socio-economic factors make the problem even more complex. Adequate timing and choice of drug prescription together with treatment adherence are very important as drug toxicities, drug failure and sub-optimal treatment regimens leave room for further development of drug resistance. While CD4 cell count and the determination of viral load from patients in resource-limited settings are very helpful to track how well a patient’s immune system is able to keep the virus in check, they can be lengthy in determining whether an ARV is effective. Phenosense assay kits answer this problem using viruses engineered to contain the patient sequences and evaluating their growth in the presence of different ARVs, but this can be expensive and too involved for routine checks. As a cheaper and faster alternative, genotypic assays provide similar information from HIV pol sequences obtained from blood samples, inferring ARV efficacy on the basis of drug resistance mutation patterns. However, these are inherently complex and the various methods of in silico prediction, such as Geno2pheno, REGA and Stanford HIVdb do not always agree in every case, even though this gap decreases as the list of resistance mutations is updated. A major gap in HIV treatment is that the information used for predicting drug resistance is mainly computed from data containing an overwhelming majority of B subtype HIV, when these only comprise about 12% of the worldwide HIV infections. In addition to growing evidence that drug resistance is subtype-related, it is intuitive to hypothesize that as subtyping is a phylogenetic classification, the more divergent a subtype is from the strains used in training prediction models, the less their resistance profiles would correlate. For the aforementioned reasons, we used a multi-faceted approach to attack the virus in multiple ways. This research aimed to (1) improve resistance prediction methods by focusing solely on the available subtype, (2) mine structural information pertaining to resistance in order to find any exploitable weak points and increase knowledge of the mechanistic processes of drug resistance in HIV protease. Finally, (3) we screen for protease inhibitors amongst a database of natural compounds [the South African natural compound database (SANCDB)] to find molecules or molecular properties usable to come up with improved inhibition against the drug target. In this work, structural information was mined using the Anisotropic Network Model, Dynamics Cross-Correlation, Perturbation Response Scanning, residue contact network analysis and the radius of gyration. These methods failed to give any resistance-associated patterns in terms of natural movement, internal correlated motions, residue perturbation response, relational behaviour and global compaction respectively. Applications of drug docking, homology-modelling and energy minimization for generating features suitable for machine-learning were not very promising, and rather suggest that the value of binding energies by themselves from Vina may not be very reliable quantitatively. All these failures lead to a refinement that resulted in a highly sensitive statistically-guided network construction and analysis, which leads to key findings in the early dynamics associated with resistance across all PI drugs. The latter experiment unravelled a conserved lateral expansion motion occurring at the flap elbows, and an associated contraction that drives the base of the dimerization domain towards the catalytic site’s floor in the case of drug resistance. Interestingly, we found that despite the conserved movement, bond angles were degenerate. Alongside, 16 Artificial Neural Network models were optimised for HIV proteases and reverse transcriptase inhibitors, with performances on par with Stanford HIVdb. Finally, we prioritised 9 compounds with potential protease inhibitory activity using virtual screening and molecular dynamics (MD) to additionally suggest a promising modification to one of the compounds. This yielded another molecule inhibiting equally well both opened and closed receptor target conformations, whereby each of the compounds had been selected against an array of multi-drug-resistant receptor variants. While a main hurdle was a lack of non-B subtype data, our findings, especially from the statistically-guided network analysis, may extrapolate to a certain extent to them as the level of conservation was very high within subtype B, despite all the present variations. This network construction method lays down a sensitive approach for analysing a pair of alternate phenotypes for which complex patterns prevail, given a sufficient number of experimental units. During the course of research a weighted contact mapping tool was developed to compare renin-angiotensinogen variants and packaged as part of the MD-TASK tool suite. Finally the functionality, compatibility and performance of the MODE-TASK tool were evaluated and confirmed for both Python2.7.x and Python3.x, for the analysis of normals modes from single protein structures and essential modes from MD trajectories. These techniques and tools collectively add onto the conventional means of MD analysis.
- Full Text:
- Authors: Sheik Amamuddy, Olivier Serge André
- Date: 2020
- Subjects: Machine learning , Molecules -- Models , Data mining , Neural networks (Computer science) , Antiretroviral agents , Protease inhibitors , Drug resistance , Multidrug resistance , Molecular dynamics , Renin-angiotensin system , HIV (Viruses) -- South Africa , HIV (Viruses) -- Social aspects -- South Africa , South African Natural Compounds Database
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/115964 , vital:34282
- Description: Millions are affected with the Human Immunodeficiency Virus (HIV) world wide, even though the death toll is on the decline. Antiretrovirals (ARVs), more specifically protease inhibitors have shown tremendous success since their introduction into therapy since the mid 1990’s by slowing down progression to the Acquired Immune Deficiency Syndrome (AIDS). However, Drug Resistance Mutations (DRMs) are constantly selected for due to viral adaptation, making drugs less effective over time. The current challenge is to manage the infection optimally with a limited set of drugs, with differing associated levels of toxicities in the face of a virus that (1) exists as a quasispecies, (2) may transmit acquired DRMs to drug-naive individuals and (3) that can manifest class-wide resistance due to similarities in design. The presence of latent reservoirs, unawareness of infection status, education and various socio-economic factors make the problem even more complex. Adequate timing and choice of drug prescription together with treatment adherence are very important as drug toxicities, drug failure and sub-optimal treatment regimens leave room for further development of drug resistance. While CD4 cell count and the determination of viral load from patients in resource-limited settings are very helpful to track how well a patient’s immune system is able to keep the virus in check, they can be lengthy in determining whether an ARV is effective. Phenosense assay kits answer this problem using viruses engineered to contain the patient sequences and evaluating their growth in the presence of different ARVs, but this can be expensive and too involved for routine checks. As a cheaper and faster alternative, genotypic assays provide similar information from HIV pol sequences obtained from blood samples, inferring ARV efficacy on the basis of drug resistance mutation patterns. However, these are inherently complex and the various methods of in silico prediction, such as Geno2pheno, REGA and Stanford HIVdb do not always agree in every case, even though this gap decreases as the list of resistance mutations is updated. A major gap in HIV treatment is that the information used for predicting drug resistance is mainly computed from data containing an overwhelming majority of B subtype HIV, when these only comprise about 12% of the worldwide HIV infections. In addition to growing evidence that drug resistance is subtype-related, it is intuitive to hypothesize that as subtyping is a phylogenetic classification, the more divergent a subtype is from the strains used in training prediction models, the less their resistance profiles would correlate. For the aforementioned reasons, we used a multi-faceted approach to attack the virus in multiple ways. This research aimed to (1) improve resistance prediction methods by focusing solely on the available subtype, (2) mine structural information pertaining to resistance in order to find any exploitable weak points and increase knowledge of the mechanistic processes of drug resistance in HIV protease. Finally, (3) we screen for protease inhibitors amongst a database of natural compounds [the South African natural compound database (SANCDB)] to find molecules or molecular properties usable to come up with improved inhibition against the drug target. In this work, structural information was mined using the Anisotropic Network Model, Dynamics Cross-Correlation, Perturbation Response Scanning, residue contact network analysis and the radius of gyration. These methods failed to give any resistance-associated patterns in terms of natural movement, internal correlated motions, residue perturbation response, relational behaviour and global compaction respectively. Applications of drug docking, homology-modelling and energy minimization for generating features suitable for machine-learning were not very promising, and rather suggest that the value of binding energies by themselves from Vina may not be very reliable quantitatively. All these failures lead to a refinement that resulted in a highly sensitive statistically-guided network construction and analysis, which leads to key findings in the early dynamics associated with resistance across all PI drugs. The latter experiment unravelled a conserved lateral expansion motion occurring at the flap elbows, and an associated contraction that drives the base of the dimerization domain towards the catalytic site’s floor in the case of drug resistance. Interestingly, we found that despite the conserved movement, bond angles were degenerate. Alongside, 16 Artificial Neural Network models were optimised for HIV proteases and reverse transcriptase inhibitors, with performances on par with Stanford HIVdb. Finally, we prioritised 9 compounds with potential protease inhibitory activity using virtual screening and molecular dynamics (MD) to additionally suggest a promising modification to one of the compounds. This yielded another molecule inhibiting equally well both opened and closed receptor target conformations, whereby each of the compounds had been selected against an array of multi-drug-resistant receptor variants. While a main hurdle was a lack of non-B subtype data, our findings, especially from the statistically-guided network analysis, may extrapolate to a certain extent to them as the level of conservation was very high within subtype B, despite all the present variations. This network construction method lays down a sensitive approach for analysing a pair of alternate phenotypes for which complex patterns prevail, given a sufficient number of experimental units. During the course of research a weighted contact mapping tool was developed to compare renin-angiotensinogen variants and packaged as part of the MD-TASK tool suite. Finally the functionality, compatibility and performance of the MODE-TASK tool were evaluated and confirmed for both Python2.7.x and Python3.x, for the analysis of normals modes from single protein structures and essential modes from MD trajectories. These techniques and tools collectively add onto the conventional means of MD analysis.
- Full Text:
Assessing community structure and trophic interrelationships in three differently impacted headwater streams in the AmatholeWinterberg freshwater ecoregion, South Africa
- Authors: Matomela, Nonjabulo Happy
- Date: 2020
- Subjects: Stream ecology -- South Africa -- Eastern Cape , Freshwater animals -- Ecology -- South Africa -- Eastern Cape , Kat River (South Africa) -- , Lushington River (South Africa) , Elands River (South Africa) , Eyre River (South Africa) , Food chains (Ecology) -- South Africa -- Eastern Cape , Water quality -- South Africa -- Eastern Cape , Land use -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/147653 , vital:38658
- Description: Afromontane regions represent some of the highly threatened ecosystems on the planet as they harbour endemic and often relic freshwater fauna. These ecologically sensitive ecosystems have been altered by multiple impacts, including invasion by non-native fishes, replacement of diverse indigenous vegetation with monoculture plantations, agricultural and mining activities, hydrological modifications, and degradation of instream habitats, with potential detrimental effects on aquatic community structures and food web dynamics. The aim of the present study was to compare spatio-temporal patterns of macroinvertebrate and fish communities as well as food web dynamics in three differently impacted headwater tributaries of the Kat River in the Amathole-Winterberg freshwater ecoregion in the Eastern Cape Province of South Africa. The upper Kat River catchment was the ideal model for purposes of the present study as it contains streams with varying degrees of human impact. The streams considered in the present study were (i) the Eyre River which was considered to closely represent near-natural conditions as it is the least impacted stream in this catchment, with the riparian zone dominated by relatively intact and diverse native woody vegetation, (ii) the Elands River whose catchment has been altered by agricultural activities, and (iii) the Lushington River, whose riparian zone has been heavily invaded by black wattle. The three headwater streams were generally distinguished based on the physical-chemical variables. The Elands River was characterised by high conductivity and total dissolved solids (TDS). In addition, the Elands River was more alkaline and relatively warmer than the other two rivers. This suggested the negative influence of agriculture activities on the water quality in the Elands River. In general, the Lushington and Eyre rivers had comparable physical and chemical variables. However, the Lushington River was generally characterised by low streamflow, likely as a consequent of black wattle which is known for altering hydrological regimes of streams .The Eyre River and Lushington River were comparable in terms of macroinvertebrate richness and diversity, whereas the Elands River was characterised by low macroinvertebrate diversity and richness. Redundancy analysis indicated that the macroinvertebrate communities were mostly influenced by seasonality, with land-use accounting for a small but significant difference in community composition. In comparison, the generalised linear mixed-effects models (GLMMs) showed that chubbyhead barb abundance was significantly influenced by land-use patterns. Evaluation of food web dynamics using stable isotope analysis revealed that the food web structure in the three rivers differed substantially as a result of land-use. Specifically, the Eyre River was characterised by less variation in stable isotope values of basal food sources and consequently, the consumer groups had a narrow isotopic breadth. In contrast, the Elands River was characterised by a wide variation in basal food sources and therefore, a wider isotopic breadth for consumers. The Lushington River was spatially variable in terms of basal sources and isotopic breadth for consumers. The study concluded that food webs and trophic interrelationships were a more informative indicator of land-use than community structure was in evaluating the impact of land-use patterns on aquatic communities. In addition, future studies should seek to investigate food webs interrelationships in addition to community structure to infer a more conclusive river assessment.
- Full Text:
- Authors: Matomela, Nonjabulo Happy
- Date: 2020
- Subjects: Stream ecology -- South Africa -- Eastern Cape , Freshwater animals -- Ecology -- South Africa -- Eastern Cape , Kat River (South Africa) -- , Lushington River (South Africa) , Elands River (South Africa) , Eyre River (South Africa) , Food chains (Ecology) -- South Africa -- Eastern Cape , Water quality -- South Africa -- Eastern Cape , Land use -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/147653 , vital:38658
- Description: Afromontane regions represent some of the highly threatened ecosystems on the planet as they harbour endemic and often relic freshwater fauna. These ecologically sensitive ecosystems have been altered by multiple impacts, including invasion by non-native fishes, replacement of diverse indigenous vegetation with monoculture plantations, agricultural and mining activities, hydrological modifications, and degradation of instream habitats, with potential detrimental effects on aquatic community structures and food web dynamics. The aim of the present study was to compare spatio-temporal patterns of macroinvertebrate and fish communities as well as food web dynamics in three differently impacted headwater tributaries of the Kat River in the Amathole-Winterberg freshwater ecoregion in the Eastern Cape Province of South Africa. The upper Kat River catchment was the ideal model for purposes of the present study as it contains streams with varying degrees of human impact. The streams considered in the present study were (i) the Eyre River which was considered to closely represent near-natural conditions as it is the least impacted stream in this catchment, with the riparian zone dominated by relatively intact and diverse native woody vegetation, (ii) the Elands River whose catchment has been altered by agricultural activities, and (iii) the Lushington River, whose riparian zone has been heavily invaded by black wattle. The three headwater streams were generally distinguished based on the physical-chemical variables. The Elands River was characterised by high conductivity and total dissolved solids (TDS). In addition, the Elands River was more alkaline and relatively warmer than the other two rivers. This suggested the negative influence of agriculture activities on the water quality in the Elands River. In general, the Lushington and Eyre rivers had comparable physical and chemical variables. However, the Lushington River was generally characterised by low streamflow, likely as a consequent of black wattle which is known for altering hydrological regimes of streams .The Eyre River and Lushington River were comparable in terms of macroinvertebrate richness and diversity, whereas the Elands River was characterised by low macroinvertebrate diversity and richness. Redundancy analysis indicated that the macroinvertebrate communities were mostly influenced by seasonality, with land-use accounting for a small but significant difference in community composition. In comparison, the generalised linear mixed-effects models (GLMMs) showed that chubbyhead barb abundance was significantly influenced by land-use patterns. Evaluation of food web dynamics using stable isotope analysis revealed that the food web structure in the three rivers differed substantially as a result of land-use. Specifically, the Eyre River was characterised by less variation in stable isotope values of basal food sources and consequently, the consumer groups had a narrow isotopic breadth. In contrast, the Elands River was characterised by a wide variation in basal food sources and therefore, a wider isotopic breadth for consumers. The Lushington River was spatially variable in terms of basal sources and isotopic breadth for consumers. The study concluded that food webs and trophic interrelationships were a more informative indicator of land-use than community structure was in evaluating the impact of land-use patterns on aquatic communities. In addition, future studies should seek to investigate food webs interrelationships in addition to community structure to infer a more conclusive river assessment.
- Full Text:
Assessing invasive alien aquatic plant species, phytoremediation effects using biological indicators in the Swartkops River system
- Authors: Tshithukhe, Getrude
- Date: 2020
- Subjects: Aquatic weeds -- Biological control -- South Africa -- Eastern Cape , Alien plants -- Biological control -- South Africa -- Eastern Cape , Phytoremediation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/167665 , vital:41501
- Description: Pollution effluents in freshwater ecosystems are becoming increasingly ubiquitous as a result of cumulative anthropogenic activities, such as wastewater treatments works, and industrial, agricultural and mining activities. These activities are more noticeable in urban river atchments where there is greater human population densities and industrial developments. The ecological effects of anthropogenic activities on freshwater ecosystems include: excessive deposition of contaminants such as nutrients, pharmaceuticals, microplastics and other chemicals, which change physicochemical properties, causing a decline in aquatic biodiversity. These effects, impact negatively on the resilience of freshwater, making the systems vulnerable to invasion by alien aquatic plants. Ultimately, the loss of local biodiversity associated with the invasive alien aquatic plants (IAAP) results in a loss of some ecosystem goods and services. The Swartkops River system, Eastern Cape Province, drains most of the neighbouring formal and informal settlements, agricultural lands and industries, and hence is exposed to water pollution from human activities along the river catchment. Various water quality assessments are needed to evaluate the extent of pollutants and their impacts on the river ecosystem. Phytoremediation is one approach employed internationally for removing harmful nutrients and chemicals in freshwater ecosystems. Most studies measure the success of phytoremediation through measuring the reduction of contaminants in water or soil chemistry in mesocosm settings, which may not take into account all the important environmental factors that exist in the field. The present study assesses the phytoremediation potential of Pontederia (Eichhornia) crassipes and Salvinia molesta by evaluating water and sediment chemistry, periphyton and aquatic macroinvertebrate community recovery along seven field sites (excluding IAAP species mats sites) located upstream and downstream IAAP species mats on the Swartkops River between April and September 2018. Water and sediment samples were collected once monthly on ten seven field sites, including the IAAP species mat sites. Periphyton and aquatic macroinvertebrates were collected on seven sites, excluding the IAAP mat sites. Pontederia crassipes and S. molesta infestation in Swartkops River showed positive phytoremediation results and improved some water and sediment chemistry in the downstream treatments as compared to upstream treatments. Although there were some fluctuations with some variables, important water and sediment chemistry were reduced downstream. By contrast, biological assessment results did not show any response to the presence of IAAP species and phytoremediation. Periphyton and aquatic macroinvertebrates diversity and community assemblages were more influenced by water quality. Although IAAP species did provide improvement in water and sediments chemistry, multiple effluent point and non-point sources in Swartkops outpaced phytoremediation. Taxa evenness and relative taxa abundance showed significant differences between the upstream and downstream sites, however taxa richness and Shannon’s diversity showed no significant differences, indicating no relative recovery in biodiversity for either periphyton or aquatic macroinvertebrates. Similarly, the upstream and downstream sites showed similar periphyton and aquatic macroinvertebrates assemblages structure, all dominated by pollution tolerant taxa, thus indicating no functional diversity improvement down river; because of improvement in water chemistry downstream sites, it was expected that periphyton and aquatic macroinvertebrates assemblage structure would also improve at these downstream sites.It is possible that the phytoremediation process is outpaced by effluent discharges, given the multiple sources and distance between upstream and downstream mat sites. The study showed phytoremediation potential but the results were not indicated by biological indicators. A replica study conducted on a moderately disturbed river system is recommended to measure the success and recovery of biological indicators and assemblage composition following IAAP species phytoremediation; a moderately disturbed river compared to a largely disturbed river will broaden findings and look at differences for a wider application of phytoremediation.
- Full Text:
- Authors: Tshithukhe, Getrude
- Date: 2020
- Subjects: Aquatic weeds -- Biological control -- South Africa -- Eastern Cape , Alien plants -- Biological control -- South Africa -- Eastern Cape , Phytoremediation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/167665 , vital:41501
- Description: Pollution effluents in freshwater ecosystems are becoming increasingly ubiquitous as a result of cumulative anthropogenic activities, such as wastewater treatments works, and industrial, agricultural and mining activities. These activities are more noticeable in urban river atchments where there is greater human population densities and industrial developments. The ecological effects of anthropogenic activities on freshwater ecosystems include: excessive deposition of contaminants such as nutrients, pharmaceuticals, microplastics and other chemicals, which change physicochemical properties, causing a decline in aquatic biodiversity. These effects, impact negatively on the resilience of freshwater, making the systems vulnerable to invasion by alien aquatic plants. Ultimately, the loss of local biodiversity associated with the invasive alien aquatic plants (IAAP) results in a loss of some ecosystem goods and services. The Swartkops River system, Eastern Cape Province, drains most of the neighbouring formal and informal settlements, agricultural lands and industries, and hence is exposed to water pollution from human activities along the river catchment. Various water quality assessments are needed to evaluate the extent of pollutants and their impacts on the river ecosystem. Phytoremediation is one approach employed internationally for removing harmful nutrients and chemicals in freshwater ecosystems. Most studies measure the success of phytoremediation through measuring the reduction of contaminants in water or soil chemistry in mesocosm settings, which may not take into account all the important environmental factors that exist in the field. The present study assesses the phytoremediation potential of Pontederia (Eichhornia) crassipes and Salvinia molesta by evaluating water and sediment chemistry, periphyton and aquatic macroinvertebrate community recovery along seven field sites (excluding IAAP species mats sites) located upstream and downstream IAAP species mats on the Swartkops River between April and September 2018. Water and sediment samples were collected once monthly on ten seven field sites, including the IAAP species mat sites. Periphyton and aquatic macroinvertebrates were collected on seven sites, excluding the IAAP mat sites. Pontederia crassipes and S. molesta infestation in Swartkops River showed positive phytoremediation results and improved some water and sediment chemistry in the downstream treatments as compared to upstream treatments. Although there were some fluctuations with some variables, important water and sediment chemistry were reduced downstream. By contrast, biological assessment results did not show any response to the presence of IAAP species and phytoremediation. Periphyton and aquatic macroinvertebrates diversity and community assemblages were more influenced by water quality. Although IAAP species did provide improvement in water and sediments chemistry, multiple effluent point and non-point sources in Swartkops outpaced phytoremediation. Taxa evenness and relative taxa abundance showed significant differences between the upstream and downstream sites, however taxa richness and Shannon’s diversity showed no significant differences, indicating no relative recovery in biodiversity for either periphyton or aquatic macroinvertebrates. Similarly, the upstream and downstream sites showed similar periphyton and aquatic macroinvertebrates assemblages structure, all dominated by pollution tolerant taxa, thus indicating no functional diversity improvement down river; because of improvement in water chemistry downstream sites, it was expected that periphyton and aquatic macroinvertebrates assemblage structure would also improve at these downstream sites.It is possible that the phytoremediation process is outpaced by effluent discharges, given the multiple sources and distance between upstream and downstream mat sites. The study showed phytoremediation potential but the results were not indicated by biological indicators. A replica study conducted on a moderately disturbed river system is recommended to measure the success and recovery of biological indicators and assemblage composition following IAAP species phytoremediation; a moderately disturbed river compared to a largely disturbed river will broaden findings and look at differences for a wider application of phytoremediation.
- Full Text: