BEd foundation phase fourth year student teachers’ self-efficacy beliefs towards teaching mathematics and the self-reported factors that influence these self-efficacy beliefs
- Authors: Harrison, Chloe
- Date: 2020
- Subjects: Mathematics -- Study and teaching (Elementary) -- South Africa , Mathematics teachers -- Training of -- South Africa , Educational evaluation -- South Africa , Student teachers -- Training of -- South Africa , Student teachers -- Rating of -- South Africa , Social cognitive theory , Self-efficacy
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/147004 , vital:38584
- Description: The underperformance of mathematics teaching and learning is a pressing concern in South Africa. Many foundation phase in-service teachers show inadequate mathematics content knowledge which creates barriers to their learners acquiring adequate mathematics skills. Teacher training programmes offer a key opportunity to improve the instructional practices of teachers at foundation phase level. In order to improve the teaching skills of in-service teachers, one focus must be on teacher training programmes. Unfortunately, there are many foundation phase student teachers who are leaving the profession within the first few years of teaching reportedly due to low levels of motivation. This research investigates the self-efficacy beliefs of pre-service student teachers. It also focuses on foundation phase student teachers as they experience significant challenges to their self-efficacy beliefs in mathematics and mathematics teaching. Self-efficacy is the key theory of the study. It stems from Bandura’s social cognitive theory and is an individual’s judgments about their capabilities, skills and perceived performance. This qualitative research adopts an interpretivist approach which seeks to identify Bed foundation phase fourth year student teachers’ self-efficacy beliefs towards teaching mathematics and the self-reported factors influencing such beliefs. This research found that BEd foundation phase fourth year student teachers have low self-efficacy beliefs towards teaching mathematics. The purpose of this research is to raise awareness of the BEd student teachers’ low self-efficacy beliefs towards teaching mathematics. The results from this research will provide a platform for future intervention research, as well as potentially influencing student teacher training programmes.
- Full Text:
- Date Issued: 2020
- Authors: Harrison, Chloe
- Date: 2020
- Subjects: Mathematics -- Study and teaching (Elementary) -- South Africa , Mathematics teachers -- Training of -- South Africa , Educational evaluation -- South Africa , Student teachers -- Training of -- South Africa , Student teachers -- Rating of -- South Africa , Social cognitive theory , Self-efficacy
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/147004 , vital:38584
- Description: The underperformance of mathematics teaching and learning is a pressing concern in South Africa. Many foundation phase in-service teachers show inadequate mathematics content knowledge which creates barriers to their learners acquiring adequate mathematics skills. Teacher training programmes offer a key opportunity to improve the instructional practices of teachers at foundation phase level. In order to improve the teaching skills of in-service teachers, one focus must be on teacher training programmes. Unfortunately, there are many foundation phase student teachers who are leaving the profession within the first few years of teaching reportedly due to low levels of motivation. This research investigates the self-efficacy beliefs of pre-service student teachers. It also focuses on foundation phase student teachers as they experience significant challenges to their self-efficacy beliefs in mathematics and mathematics teaching. Self-efficacy is the key theory of the study. It stems from Bandura’s social cognitive theory and is an individual’s judgments about their capabilities, skills and perceived performance. This qualitative research adopts an interpretivist approach which seeks to identify Bed foundation phase fourth year student teachers’ self-efficacy beliefs towards teaching mathematics and the self-reported factors influencing such beliefs. This research found that BEd foundation phase fourth year student teachers have low self-efficacy beliefs towards teaching mathematics. The purpose of this research is to raise awareness of the BEd student teachers’ low self-efficacy beliefs towards teaching mathematics. The results from this research will provide a platform for future intervention research, as well as potentially influencing student teacher training programmes.
- Full Text:
- Date Issued: 2020
Red and other short stories
- Authors: Harrison, Francis J
- Date: 2020
- Subjects: South African fiction (English) -- 21st century
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/141583 , vital:37987
- Description: Part A: Thesis (Creative Work);Part B: Portfolio. Final submission for the degree of Master of Arts in Creative Writing (MACW).
- Full Text:
- Date Issued: 2020
- Authors: Harrison, Francis J
- Date: 2020
- Subjects: South African fiction (English) -- 21st century
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/141583 , vital:37987
- Description: Part A: Thesis (Creative Work);Part B: Portfolio. Final submission for the degree of Master of Arts in Creative Writing (MACW).
- Full Text:
- Date Issued: 2020
“Why me, Lord?”: some social factors associated with the receipt of a donor heart in South Africa
- Authors: Hartle, Raymond
- Date: 2020
- Subjects: Heart -- Transplantation -- Social aspects , Heart -- Transplantation -- Recipients -- Psychology , Heart -- Transplantation -- South Africa , Chronic diseases -- Psychological aspects
- Language: English
- Type: text , Thesis , Masters , MSocSci
- Identifier: http://hdl.handle.net/10962/146265 , vital:38510
- Description: Since the first human-to-human heart transplant in the world was performed by Prof Chris Barnard in Cape Town in 1967, heart transplantation has become the gold standard to treat people suffering from end stage heart failure. This thesis explores heart recipients’ perceptions and experiences of their chronic heart illness before and after transplantation. It examines the medical experience in terms of the clinical diagnosis, the standard of communication about the illness and the proposed treatment, and the post-transplant regime. It also reflects how recipients make sense of heart disease and learn to live with a transplanted heart. The thesis also shows the extent to which the recipients’ culture and individual identity impact such complex medical issues as end stage heart failure and transplantation. Qualitative research was undertaken in private sector heart transplant programmes in South Africa. The study is underpinned by Mishel’s (1990) uncertainty theory as well as by social constructionism.
- Full Text:
- Date Issued: 2020
- Authors: Hartle, Raymond
- Date: 2020
- Subjects: Heart -- Transplantation -- Social aspects , Heart -- Transplantation -- Recipients -- Psychology , Heart -- Transplantation -- South Africa , Chronic diseases -- Psychological aspects
- Language: English
- Type: text , Thesis , Masters , MSocSci
- Identifier: http://hdl.handle.net/10962/146265 , vital:38510
- Description: Since the first human-to-human heart transplant in the world was performed by Prof Chris Barnard in Cape Town in 1967, heart transplantation has become the gold standard to treat people suffering from end stage heart failure. This thesis explores heart recipients’ perceptions and experiences of their chronic heart illness before and after transplantation. It examines the medical experience in terms of the clinical diagnosis, the standard of communication about the illness and the proposed treatment, and the post-transplant regime. It also reflects how recipients make sense of heart disease and learn to live with a transplanted heart. The thesis also shows the extent to which the recipients’ culture and individual identity impact such complex medical issues as end stage heart failure and transplantation. Qualitative research was undertaken in private sector heart transplant programmes in South Africa. The study is underpinned by Mishel’s (1990) uncertainty theory as well as by social constructionism.
- Full Text:
- Date Issued: 2020
Reef fish associations with benthic habitats at a remote protected coral reef ecosystem in the Western Indian Ocean-Aldabra Atoll, Seychelles
- Authors: Haupt, Philip
- Date: 2020
- Subjects: Coral reef ecology -- Aldabra Islands (Seychelles) , Reef fishes -- Aldabra Islands (Seychelles) , Benthic animals -- Aldabra Islands (Seychelles)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/141629 , vital:37991
- Description: The aim of the thesis is to develop an understanding of the associations between reef fish and benthic habitats and assess the modifying effects of environmental processes on these relationships at Aldabra, a pristine atoll in the Western Indian Ocean (WIO). Conducting research in pristine, or reference coral reef ecosystem, removes the impact of direct anthropogenic disturbances and provides essential information on natural ecosystem structure and functioning. Three primary hypotheses were tested: 1) Environmental drivers such as depth and exposure to wave energy determine the spatial distribution of benthic habitats; 2) The reef fish assemblage structure is explained by habitat at multiple scales and modified by the effects of environmental drivers such as depth, wave energy and cyclical temporal drivers such as time and tides; 3) The reef fish assemblage at Aldabra represents a pristine reef fish assemblage, comprising high levels of herbivores and predators. The research focussed on the benthic habitat on the seaward reefs between the shoreline and 50 m depth. The first objective was to characterise the benthic habitats on Aldabra Atoll’s seaward reefs and map their spatial distributions using remotely sensed imagery and ground truthing data. The second was to assess the influence of depth and exposure to wave energy on the distribution of benthic habitats. The third was to identify the most suitable standardised method to survey the reef fish assemblage structure on Aldabra’s, and fourth to determine the effect of tide and time of day on the reef fish assemblage. The fifth objective was to establish the association between reef fish assemblage structure and benthic habitats and to test how species-size influenced the scale of habitat at which the associations were most apparent. Four categories of geomorphic reef zones (reef flats (19.2 km2), top of the forereef slope (7.8 km2), deep forereef slope (11.6 km2), and reef platform (14.3 km2)) were manually delineated following the visual outlines of reef features from satellite imagery. The six broad-scale and twelve fine-scale benthic habitats were mapped using a supervised maximum likelihood classification and the spatial coverage of each determined. The broad-scale habitats were 1) Epilithic algal matrix, 2) Hard and soft (coral, 3) Rubble, 4) Macroalgae, 5) Seagrass and 6) Sand. Similarly, twelve fine-scale benthic habitats were characterised and mapped, for example, Hard coral (19 %) including massive and submassive forms with Millepora and Rhytisma. The broad-scale benthic habitat map had an overall producer accuracy of 54 % and fine-scale habitat map 29 %, which was consistent with studies using similar habitat classification methods. The prevailing wave energy, depth and the directional orientation of coral reefs (aspect) significantly influenced the probability of occurrence of each of the broad-scale benthic habitats, and there was a shift in peak probability of occurrence of all habitat categories to a greater depth with an increase in wave energy. The strong relationship of benthic habitats with depth and wave energy suggests that the distributions of benthic habitats are likely to change with sea-level rise and increased intensity and frequency of storms in future. Overall, 338 fish species from 51 families, including 14 species of elasmobranch were recorded using Baited Remote Underwater Video systems (BRUVs) and unbaited Remote Underwater Video systems (RUVS) from 231 samples. Fish were significantly more abundant when observed using BRUVs (119 ± 7) relative to RUVs (92 ± 7), and the assemblage structures were significantly different between the two sampling methods. Abundance and species richness of generalist carnivores and piscivores were significantly greater in BRUVs, while RUVs recorded significantly greater numbers of herbivores and more species of herbivore and corallivore. The results suggest that BRUVs are better suited when studying predatory fish which may not be detected without bait. However, when surveying a taxonomically and functionally diverse assemblage of fishes at a pristine reef, RUVs may provide a more accurate estimate of natural reef fish assemblage structure. Reef fish assemblages observed using RUVs were significantly different between morning-high-tide, midday-low-tide and evening-high-tide for all trophic groups. However, the reef fish assemblage structure observed using BRUVs was insensitive to change in tide and time of day, which may be explained by the attraction effect of bait dampening the effect of tide and time of day. While RUVs appear better to detect more subtle variations in fish assemblage structure, care needs to be taken when designing research programmes that use RUVs, as the sampling design should account for tide and time of day to avoid misinterpreting the cyclical variation, which may confound results. Reef fish assemblages were significantly different among habitats within geomorphic reef zones, broad-scale and fine-scale habitats. Species turnover rates were significantly different for all Actinopterygii size-class categories between the three scales of habitat. No marked differences in species turnover rates among habitats were detected for the majority of Elasmobranch size-class categories. The strong habitat dependency over various spatial scales indicates that effective conservation of Actinopterygii fish at Aldabra, and elsewhere in similar ecosystems requires protection of representative sets of benthic habitats. However, Elasmobranch conservation requires sufficiently large areas as these species utilise multiple habitats, over multiple scales, which are likely to exceed the confines of Aldabra’s reef.
- Full Text:
- Date Issued: 2020
- Authors: Haupt, Philip
- Date: 2020
- Subjects: Coral reef ecology -- Aldabra Islands (Seychelles) , Reef fishes -- Aldabra Islands (Seychelles) , Benthic animals -- Aldabra Islands (Seychelles)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/141629 , vital:37991
- Description: The aim of the thesis is to develop an understanding of the associations between reef fish and benthic habitats and assess the modifying effects of environmental processes on these relationships at Aldabra, a pristine atoll in the Western Indian Ocean (WIO). Conducting research in pristine, or reference coral reef ecosystem, removes the impact of direct anthropogenic disturbances and provides essential information on natural ecosystem structure and functioning. Three primary hypotheses were tested: 1) Environmental drivers such as depth and exposure to wave energy determine the spatial distribution of benthic habitats; 2) The reef fish assemblage structure is explained by habitat at multiple scales and modified by the effects of environmental drivers such as depth, wave energy and cyclical temporal drivers such as time and tides; 3) The reef fish assemblage at Aldabra represents a pristine reef fish assemblage, comprising high levels of herbivores and predators. The research focussed on the benthic habitat on the seaward reefs between the shoreline and 50 m depth. The first objective was to characterise the benthic habitats on Aldabra Atoll’s seaward reefs and map their spatial distributions using remotely sensed imagery and ground truthing data. The second was to assess the influence of depth and exposure to wave energy on the distribution of benthic habitats. The third was to identify the most suitable standardised method to survey the reef fish assemblage structure on Aldabra’s, and fourth to determine the effect of tide and time of day on the reef fish assemblage. The fifth objective was to establish the association between reef fish assemblage structure and benthic habitats and to test how species-size influenced the scale of habitat at which the associations were most apparent. Four categories of geomorphic reef zones (reef flats (19.2 km2), top of the forereef slope (7.8 km2), deep forereef slope (11.6 km2), and reef platform (14.3 km2)) were manually delineated following the visual outlines of reef features from satellite imagery. The six broad-scale and twelve fine-scale benthic habitats were mapped using a supervised maximum likelihood classification and the spatial coverage of each determined. The broad-scale habitats were 1) Epilithic algal matrix, 2) Hard and soft (coral, 3) Rubble, 4) Macroalgae, 5) Seagrass and 6) Sand. Similarly, twelve fine-scale benthic habitats were characterised and mapped, for example, Hard coral (19 %) including massive and submassive forms with Millepora and Rhytisma. The broad-scale benthic habitat map had an overall producer accuracy of 54 % and fine-scale habitat map 29 %, which was consistent with studies using similar habitat classification methods. The prevailing wave energy, depth and the directional orientation of coral reefs (aspect) significantly influenced the probability of occurrence of each of the broad-scale benthic habitats, and there was a shift in peak probability of occurrence of all habitat categories to a greater depth with an increase in wave energy. The strong relationship of benthic habitats with depth and wave energy suggests that the distributions of benthic habitats are likely to change with sea-level rise and increased intensity and frequency of storms in future. Overall, 338 fish species from 51 families, including 14 species of elasmobranch were recorded using Baited Remote Underwater Video systems (BRUVs) and unbaited Remote Underwater Video systems (RUVS) from 231 samples. Fish were significantly more abundant when observed using BRUVs (119 ± 7) relative to RUVs (92 ± 7), and the assemblage structures were significantly different between the two sampling methods. Abundance and species richness of generalist carnivores and piscivores were significantly greater in BRUVs, while RUVs recorded significantly greater numbers of herbivores and more species of herbivore and corallivore. The results suggest that BRUVs are better suited when studying predatory fish which may not be detected without bait. However, when surveying a taxonomically and functionally diverse assemblage of fishes at a pristine reef, RUVs may provide a more accurate estimate of natural reef fish assemblage structure. Reef fish assemblages observed using RUVs were significantly different between morning-high-tide, midday-low-tide and evening-high-tide for all trophic groups. However, the reef fish assemblage structure observed using BRUVs was insensitive to change in tide and time of day, which may be explained by the attraction effect of bait dampening the effect of tide and time of day. While RUVs appear better to detect more subtle variations in fish assemblage structure, care needs to be taken when designing research programmes that use RUVs, as the sampling design should account for tide and time of day to avoid misinterpreting the cyclical variation, which may confound results. Reef fish assemblages were significantly different among habitats within geomorphic reef zones, broad-scale and fine-scale habitats. Species turnover rates were significantly different for all Actinopterygii size-class categories between the three scales of habitat. No marked differences in species turnover rates among habitats were detected for the majority of Elasmobranch size-class categories. The strong habitat dependency over various spatial scales indicates that effective conservation of Actinopterygii fish at Aldabra, and elsewhere in similar ecosystems requires protection of representative sets of benthic habitats. However, Elasmobranch conservation requires sufficiently large areas as these species utilise multiple habitats, over multiple scales, which are likely to exceed the confines of Aldabra’s reef.
- Full Text:
- Date Issued: 2020
South Africa’s mohair value chain: institutional framework, governance and the perceptions of management and labour
- Authors: Heald, Arisa Oka
- Date: 2020
- Subjects: Management -- Employee participation , Management -- Employee participation -- South Africa , Agriculture -- South Africa -- History , Mohair industry -- South Africa , Mohair industry -- South Africa -- Employees
- Language: English
- Type: text , Thesis , Masters , MSocSci
- Identifier: http://hdl.handle.net/10962/164669 , vital:41153
- Description: The primary objective of this research is to understand the ways in which the (working and living) conditions confronting employers and employees on mohair farms are the complex outcome of their position in the global mohair value chain, the nature of the labour process, and the ‘contours of voice’ (i.e., how and why employees voice). These three bodies of literature represent different levels of analysis: at the broadest level, the political economy of the mohair value chain is explained by drawing on the chain literature. This literature has been supplemented, at the level of the production process, by deploying the concepts of labour process theory (LPT), which focus on the control of work processes by management as well as workers’responses to this control. These responses were analysed by incorporating insights from the burgeoning research on employee voice (EV) in an effort to understand the practical ways in which workers on mohair farms articulate their needs and interests. The cross-collination of these three bodies of literature is, to my knowledge, a novel feature of this research on the mohair industry in South Africa, which, in turn, has itself been woefully under-researched. The research design consisted of a qualitative approach in which I used in-depth, semi-structured interviews and focus-group discussions as the primary sources of data collection. The secondary source of data was available publications and documents from the agriculture industry and mohair sector. A qualitative approach acknowledges and gives great insight and meaning into the research topic. Twenty participants were interviewed for my research: six from key organisations within the mohair industry, ten farmers, two mohair farm workers and two mohair shearers. The main findings of the research include the following: first, institutions in South Africa’s mohair industry not only determine (in part) the structure of the mohair value chain but also play a vital role in governing the chain. Each institution and actor plays a significant role in adding value to the mohair product that leads to economic upgrading. Second, understanding the actions of farmers (as employers) by drawing on LPT allows me to show how the systemic pressures of capitalist accumulation compel employers to continuously enhance their control over production – and, by extension, over workers – who, in turn, resist and/or accommodate to these impositions by management. Lastly, the research shows that employee voice at the farm level is complex and contested – not surprisingly, given South Africa’s troubled history – yet, it is increasingly exercised by farm workers and accepted by mohair farmers as a necessary and inescapable means of resolving issues that arise in the employment relationship at the workplace and remaining competitive in a global market.
- Full Text:
- Date Issued: 2020
- Authors: Heald, Arisa Oka
- Date: 2020
- Subjects: Management -- Employee participation , Management -- Employee participation -- South Africa , Agriculture -- South Africa -- History , Mohair industry -- South Africa , Mohair industry -- South Africa -- Employees
- Language: English
- Type: text , Thesis , Masters , MSocSci
- Identifier: http://hdl.handle.net/10962/164669 , vital:41153
- Description: The primary objective of this research is to understand the ways in which the (working and living) conditions confronting employers and employees on mohair farms are the complex outcome of their position in the global mohair value chain, the nature of the labour process, and the ‘contours of voice’ (i.e., how and why employees voice). These three bodies of literature represent different levels of analysis: at the broadest level, the political economy of the mohair value chain is explained by drawing on the chain literature. This literature has been supplemented, at the level of the production process, by deploying the concepts of labour process theory (LPT), which focus on the control of work processes by management as well as workers’responses to this control. These responses were analysed by incorporating insights from the burgeoning research on employee voice (EV) in an effort to understand the practical ways in which workers on mohair farms articulate their needs and interests. The cross-collination of these three bodies of literature is, to my knowledge, a novel feature of this research on the mohair industry in South Africa, which, in turn, has itself been woefully under-researched. The research design consisted of a qualitative approach in which I used in-depth, semi-structured interviews and focus-group discussions as the primary sources of data collection. The secondary source of data was available publications and documents from the agriculture industry and mohair sector. A qualitative approach acknowledges and gives great insight and meaning into the research topic. Twenty participants were interviewed for my research: six from key organisations within the mohair industry, ten farmers, two mohair farm workers and two mohair shearers. The main findings of the research include the following: first, institutions in South Africa’s mohair industry not only determine (in part) the structure of the mohair value chain but also play a vital role in governing the chain. Each institution and actor plays a significant role in adding value to the mohair product that leads to economic upgrading. Second, understanding the actions of farmers (as employers) by drawing on LPT allows me to show how the systemic pressures of capitalist accumulation compel employers to continuously enhance their control over production – and, by extension, over workers – who, in turn, resist and/or accommodate to these impositions by management. Lastly, the research shows that employee voice at the farm level is complex and contested – not surprisingly, given South Africa’s troubled history – yet, it is increasingly exercised by farm workers and accepted by mohair farmers as a necessary and inescapable means of resolving issues that arise in the employment relationship at the workplace and remaining competitive in a global market.
- Full Text:
- Date Issued: 2020
An Analysis of Internet Background Radiation within an African IPv4 netblock
- Authors: Hendricks, Wadeegh
- Date: 2020
- Subjects: Computer networks -- Monitoring –- South Africa , Dark Web , Computer networks -- Security measures –- South Africa , Universities and Colleges -- Computer networks -- Security measures , Malware (Computer software) , TCP/IP (Computer network protocol)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/103791 , vital:32298
- Description: The use of passive network sensors has in the past proven to be quite effective in monitoring and analysing the current state of traffic on a network. Internet traffic destined to a routable, yet unused address block is often referred to as Internet Background Radiation (IBR) and characterised as unsolicited. This unsolicited traffic is however quite valuable to researchers in that it allows them to study the traffic patterns in a covert manner. IBR is largely composed of network and port scanning traffic, backscatter packets from virus and malware activity and to a lesser extent, misconfiguration of network devices. This research answers the following two questions: (1) What is the current state of IBR within the context of a South African IP address space and (2) Can any anomalies be detected in the traffic, with specific reference to current global malware attacks such as Mirai and similar. Rhodes University operates five IPv4 passive network sensors, commonly known as network telescopes, each monitoring its own /24 IP address block. The oldest of these network telescopes has been collecting traffic for over a decade, with the newest being established in 2011. This research focuses on the in-depth analysis of the traffic captured by one telescope in the 155/8 range over a 12 month period, from January to December 2017. The traffic was analysed and classified according the protocol, TCP flag, source IP address, destination port, packet count and payload size. Apart from the normal network traffic graphs and tables, a geographic heatmap of source traffic was also created, based on the source IP address. Spikes and noticeable variances in traffic patterns were further investigated and evidence of Mirai like malware activity was observed. Network and port scanning were found to comprise the largest amount of traffic, accounting for over 90% of the total IBR. Various scanning techniques were identified, including low level passive scanning and much higher level active scanning.
- Full Text:
- Date Issued: 2020
- Authors: Hendricks, Wadeegh
- Date: 2020
- Subjects: Computer networks -- Monitoring –- South Africa , Dark Web , Computer networks -- Security measures –- South Africa , Universities and Colleges -- Computer networks -- Security measures , Malware (Computer software) , TCP/IP (Computer network protocol)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/103791 , vital:32298
- Description: The use of passive network sensors has in the past proven to be quite effective in monitoring and analysing the current state of traffic on a network. Internet traffic destined to a routable, yet unused address block is often referred to as Internet Background Radiation (IBR) and characterised as unsolicited. This unsolicited traffic is however quite valuable to researchers in that it allows them to study the traffic patterns in a covert manner. IBR is largely composed of network and port scanning traffic, backscatter packets from virus and malware activity and to a lesser extent, misconfiguration of network devices. This research answers the following two questions: (1) What is the current state of IBR within the context of a South African IP address space and (2) Can any anomalies be detected in the traffic, with specific reference to current global malware attacks such as Mirai and similar. Rhodes University operates five IPv4 passive network sensors, commonly known as network telescopes, each monitoring its own /24 IP address block. The oldest of these network telescopes has been collecting traffic for over a decade, with the newest being established in 2011. This research focuses on the in-depth analysis of the traffic captured by one telescope in the 155/8 range over a 12 month period, from January to December 2017. The traffic was analysed and classified according the protocol, TCP flag, source IP address, destination port, packet count and payload size. Apart from the normal network traffic graphs and tables, a geographic heatmap of source traffic was also created, based on the source IP address. Spikes and noticeable variances in traffic patterns were further investigated and evidence of Mirai like malware activity was observed. Network and port scanning were found to comprise the largest amount of traffic, accounting for over 90% of the total IBR. Various scanning techniques were identified, including low level passive scanning and much higher level active scanning.
- Full Text:
- Date Issued: 2020
Seasonal trends of rainfall intensity, ground cover and sediment dynamics in the Little Pot River and Gqukunqa River catchments, South Africa
- Authors: Herd-Hoare, Sean
- Date: 2020
- Subjects: Land degradation -- Control -- South Africa -- Eastern Cape , Vegetation mapping -- South Africa -- Eastern Cape , Rain and rainfall -- South Africa -- Eastern Cape , Gqukunqa River catchment (South Africa) , Little Pot River catchment (South Africa) , Tsitsa River catchment (South Africa)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/146288 , vital:38512
- Description: Natural rangelands provide a variety of ecosystem services including livestock production which occurs on land under freehold land tenure and on land under communal tenure. There is an ongoing debate around the extent to which land degradation is occurring on these rangelands under different land management and land tenure systems and what the main degradation drivers are. Over-grazing, rainfall and soil type are key drivers of rangeland dynamics and the resultant sediment yield in the river systems, however, over-grazing is an outcome of land management while rainfall and soil type are natural drivers. This study explores the relationship between rainfall and daily sediment flux as well as the seasonal trends of vegetation cover and the study is part of a greater research effort called the Tsitsa Project which is based in the Tsitsa River catchment (near Maclear, Eastern Cape, South Africa). The Tsitsa Project aims at developing and managing both land and water in a sustainable way by improving the land, water and lives of people living in the Tsitsa River catchment. The restoration efforts of the Tstisa Project will aid in extending the lifespan of both the proposed dams on the Tsitsa River. The Tsitsa River catchment is characterised by grasslands, steep topography, highly erodible soils with many large gullies present and a very high sediment yield in the Tsitsa River which allowed for the exploration of some of the system drivers of sediment yield in this catchment. The study involved two sub-catchments of the Upper Tsitsa River catchment of different land management strategies: one dominated by commercial livestock farms (Little Pot River catchment) and one dominated by communal rangelands (Gqukunqa River catchment). The aim of this study was to determine the seasonal trends of rainfall intensity, ground cover and sediment dynamics in the Little Pot River and Gqukunqa River catchments. The purpose of the findings was to improve management strategies in degraded areas and catchments. In order to achieve this aim a variety of field and desktop methods were used. Field methods involved measuring variables including: vegetation biomass, vegetation cover, soil surface hardness, biocrust cover and slope angle for a range of Normalized Difference Vegetation Index (NDVI) values from the Sentinel-2A sensor. The study assessed the system response of the field variables in both catchments over one rainfall season (2018-2019). Desktop methods included various NDVI analyses as well as analyses of trends and relationships between vegetation dynamics, rainfall and sediment. The relationship between erosive rainfall events, daily rainfall, antecedent rainfall and daily sediment flux was explored over the time period of January 2016 to January 2019 and October 2015 to January 2019 for the Little Pot River catchment and the Gqukunqa River catchment respectively. NDVI was explored as a proxy for vegetation cover to extrapolate across the catchments and monitoring period. NDVI was found to have a weak positive relationship with vegetation cover and biomass (R2 values ranged from 0,04 to 0,525). Mean monthly catchment NDVI values, biomass and vegetation cover increased throughout the wet season of 2018-2019 in both catchments. Mean monthly NDVI values increased from 0,26 to 0,55 in the Little Pot River catchment and from 0,29 to 0,53 in the Gqukunqa River catchment over the course of the 2018-2019 wet season. NDVI, biomass and vegetation cover was found to be higher on south-facing slopes than north-facing slopes in both catchments for the majority of the wet season. The Gqukunqa River has significantly higher daily sediment fluxes than the Little Pot River despite similar NDVI and rainfall intensities which is owed to the dispersive soils in the Gqukunqa River catchment. Soil surface hardness results were inconclusive due to rainfall before or during every field trip which changed the properties of the soil. The largest erosive rainfall, daily rainfall and daily sediment events occurred from January to March each wet season in both catchments. Rainfall intensity and sediment fluxes were found to have a weak relationship, however, there was a stronger relationship found between antecedent rainfall and sediment flux. The larger daily sediment fluxes in each catchment often did not result from an erosive rainfall event on the same day but rather from multiple days of rainfall which can result in saturated soils and runoff leading to surface and sub-surface erosion. The possibility of sub-surface erosion via chemical processes contributing to the larger sediment events was also explored to explain the stronger relationship between antecedent rainfall and daily sediment flux.
- Full Text:
- Date Issued: 2020
- Authors: Herd-Hoare, Sean
- Date: 2020
- Subjects: Land degradation -- Control -- South Africa -- Eastern Cape , Vegetation mapping -- South Africa -- Eastern Cape , Rain and rainfall -- South Africa -- Eastern Cape , Gqukunqa River catchment (South Africa) , Little Pot River catchment (South Africa) , Tsitsa River catchment (South Africa)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/146288 , vital:38512
- Description: Natural rangelands provide a variety of ecosystem services including livestock production which occurs on land under freehold land tenure and on land under communal tenure. There is an ongoing debate around the extent to which land degradation is occurring on these rangelands under different land management and land tenure systems and what the main degradation drivers are. Over-grazing, rainfall and soil type are key drivers of rangeland dynamics and the resultant sediment yield in the river systems, however, over-grazing is an outcome of land management while rainfall and soil type are natural drivers. This study explores the relationship between rainfall and daily sediment flux as well as the seasonal trends of vegetation cover and the study is part of a greater research effort called the Tsitsa Project which is based in the Tsitsa River catchment (near Maclear, Eastern Cape, South Africa). The Tsitsa Project aims at developing and managing both land and water in a sustainable way by improving the land, water and lives of people living in the Tsitsa River catchment. The restoration efforts of the Tstisa Project will aid in extending the lifespan of both the proposed dams on the Tsitsa River. The Tsitsa River catchment is characterised by grasslands, steep topography, highly erodible soils with many large gullies present and a very high sediment yield in the Tsitsa River which allowed for the exploration of some of the system drivers of sediment yield in this catchment. The study involved two sub-catchments of the Upper Tsitsa River catchment of different land management strategies: one dominated by commercial livestock farms (Little Pot River catchment) and one dominated by communal rangelands (Gqukunqa River catchment). The aim of this study was to determine the seasonal trends of rainfall intensity, ground cover and sediment dynamics in the Little Pot River and Gqukunqa River catchments. The purpose of the findings was to improve management strategies in degraded areas and catchments. In order to achieve this aim a variety of field and desktop methods were used. Field methods involved measuring variables including: vegetation biomass, vegetation cover, soil surface hardness, biocrust cover and slope angle for a range of Normalized Difference Vegetation Index (NDVI) values from the Sentinel-2A sensor. The study assessed the system response of the field variables in both catchments over one rainfall season (2018-2019). Desktop methods included various NDVI analyses as well as analyses of trends and relationships between vegetation dynamics, rainfall and sediment. The relationship between erosive rainfall events, daily rainfall, antecedent rainfall and daily sediment flux was explored over the time period of January 2016 to January 2019 and October 2015 to January 2019 for the Little Pot River catchment and the Gqukunqa River catchment respectively. NDVI was explored as a proxy for vegetation cover to extrapolate across the catchments and monitoring period. NDVI was found to have a weak positive relationship with vegetation cover and biomass (R2 values ranged from 0,04 to 0,525). Mean monthly catchment NDVI values, biomass and vegetation cover increased throughout the wet season of 2018-2019 in both catchments. Mean monthly NDVI values increased from 0,26 to 0,55 in the Little Pot River catchment and from 0,29 to 0,53 in the Gqukunqa River catchment over the course of the 2018-2019 wet season. NDVI, biomass and vegetation cover was found to be higher on south-facing slopes than north-facing slopes in both catchments for the majority of the wet season. The Gqukunqa River has significantly higher daily sediment fluxes than the Little Pot River despite similar NDVI and rainfall intensities which is owed to the dispersive soils in the Gqukunqa River catchment. Soil surface hardness results were inconclusive due to rainfall before or during every field trip which changed the properties of the soil. The largest erosive rainfall, daily rainfall and daily sediment events occurred from January to March each wet season in both catchments. Rainfall intensity and sediment fluxes were found to have a weak relationship, however, there was a stronger relationship found between antecedent rainfall and sediment flux. The larger daily sediment fluxes in each catchment often did not result from an erosive rainfall event on the same day but rather from multiple days of rainfall which can result in saturated soils and runoff leading to surface and sub-surface erosion. The possibility of sub-surface erosion via chemical processes contributing to the larger sediment events was also explored to explain the stronger relationship between antecedent rainfall and daily sediment flux.
- Full Text:
- Date Issued: 2020
A multimodal analysis of the representations of gender in contemporary South African children’s picture books produced by Book Dash
- Authors: Heydenrych, Ellen Frances
- Date: 2020
- Subjects: Book Dash (South Africa) , Picture books for children -- South Africa , Sex role in literature , Patriarchy in literature , Children's literature, South African (English) -- 21st century -- History and criticism
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/164284 , vital:41106
- Description: In response to a demand for quality children’s picture books written and published by South Africans for local children, Book Dash – a South African non-profit organisation – has devised a publishing model in which they produce high quality children’s picture books in a twelve-hour period. Their aim is to publish books that represent a diverse range of South African children. However, while their objective is to create books that are representative of many races, this representation happens through gendered characters. In this thesis, I explore the representation of gender in Book Dash’s picture books. I use a combination of visual social semiotics, narrative theory, and critical discourse analysis, specifically focusing on the gendered ways in which the characters are represented. My analysis of these books shows how complex it can be to contest regimes of representation that work to fix patriarchal discourses and gender inequality. My findings reveal a paradox in the representation of gender norms in female characters, as some girl child characters are represented in roles that challenge gender norms, while female adult characters are consistently represented as conforming to the patriarchal feminine ideal. There is also a notable lack of father figures in these books. Such portrayals may contribute to the perpetuation of patriarchal discourses and gender inequality, particularly if these books are held up as examples of equality.
- Full Text:
- Date Issued: 2020
- Authors: Heydenrych, Ellen Frances
- Date: 2020
- Subjects: Book Dash (South Africa) , Picture books for children -- South Africa , Sex role in literature , Patriarchy in literature , Children's literature, South African (English) -- 21st century -- History and criticism
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/164284 , vital:41106
- Description: In response to a demand for quality children’s picture books written and published by South Africans for local children, Book Dash – a South African non-profit organisation – has devised a publishing model in which they produce high quality children’s picture books in a twelve-hour period. Their aim is to publish books that represent a diverse range of South African children. However, while their objective is to create books that are representative of many races, this representation happens through gendered characters. In this thesis, I explore the representation of gender in Book Dash’s picture books. I use a combination of visual social semiotics, narrative theory, and critical discourse analysis, specifically focusing on the gendered ways in which the characters are represented. My analysis of these books shows how complex it can be to contest regimes of representation that work to fix patriarchal discourses and gender inequality. My findings reveal a paradox in the representation of gender norms in female characters, as some girl child characters are represented in roles that challenge gender norms, while female adult characters are consistently represented as conforming to the patriarchal feminine ideal. There is also a notable lack of father figures in these books. Such portrayals may contribute to the perpetuation of patriarchal discourses and gender inequality, particularly if these books are held up as examples of equality.
- Full Text:
- Date Issued: 2020
The determination of whether a Unified Communication System can be effective in supporting informal communication and collaboration in virtual teams
- Authors: Hill, Kyle
- Date: 2020
- Subjects: Telecommuting , Virtual work teams , Telecommunication systems , Computer networks
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/146343 , vital:38517
- Description: The overall objective of the research is to determine whether a Unified Communication System intervention can be effective in supporting informal communication and collaboration in virtual teams. In so doing, this research is aimed at developing a current framework of critical success factors for facilitating informal collaboration and communication. As teams have evolved to the point where there is no longer a need for team members to be co-located, with a greater importance now being placed on how they collaborate, this framework will also highlight how it can support virtual teams due to the huge potential advantage they can provide to the organisation. A virtual communication and collaboration system will be selected based on the outputs of the current framework and interactions which occur through the system will be observed to provide quantitative and qualitative results. In conclusion, the research will suggest recommendations for the successful implementation of informal communication and collaboration technologies within the organisation. The research will also indicate to a limited degree, the impact of the implementation of these technologies, and the outcome for the organisation, whether positive or negative. Whilst conducting the research, it became apparent that while the UCS was capable of performing the processes and functions required, the individuals and teams engaging with the technology did not always make use of the full scope of the technology provided. Regardless, a UCS was observed to provide direct benefits to an organisation in increasing communication and collaboration in the organisation. These increases can be observed in both the physical and virtual sense. However, the converse is true for generating social capital which lead to the observation that there are a smaller number of interactions happening in the smaller teams, but these are of higher value when compared to the larger teams of this study. It is also clear that the larger a team becomes, the more the trend is to focus on adopting new technologies to make their roles more efficient. This adoption is not however translated into outputs such as social capital but is translated into stronger networks and the formation of new networks. It is also clear that most negative factors around the UCS are related to the respondent’s hardware rather than the solution itself. Cost reductions because of virtuality will also be observed and using the Developed Framework as a blue print, an organisation should be able to observe direct benefits for an organisation by being able to confirm the thesis of this research in that having a UCS intervention is effective in supporting informal communication and collaboration in virtual teams.
- Full Text:
- Date Issued: 2020
- Authors: Hill, Kyle
- Date: 2020
- Subjects: Telecommuting , Virtual work teams , Telecommunication systems , Computer networks
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/146343 , vital:38517
- Description: The overall objective of the research is to determine whether a Unified Communication System intervention can be effective in supporting informal communication and collaboration in virtual teams. In so doing, this research is aimed at developing a current framework of critical success factors for facilitating informal collaboration and communication. As teams have evolved to the point where there is no longer a need for team members to be co-located, with a greater importance now being placed on how they collaborate, this framework will also highlight how it can support virtual teams due to the huge potential advantage they can provide to the organisation. A virtual communication and collaboration system will be selected based on the outputs of the current framework and interactions which occur through the system will be observed to provide quantitative and qualitative results. In conclusion, the research will suggest recommendations for the successful implementation of informal communication and collaboration technologies within the organisation. The research will also indicate to a limited degree, the impact of the implementation of these technologies, and the outcome for the organisation, whether positive or negative. Whilst conducting the research, it became apparent that while the UCS was capable of performing the processes and functions required, the individuals and teams engaging with the technology did not always make use of the full scope of the technology provided. Regardless, a UCS was observed to provide direct benefits to an organisation in increasing communication and collaboration in the organisation. These increases can be observed in both the physical and virtual sense. However, the converse is true for generating social capital which lead to the observation that there are a smaller number of interactions happening in the smaller teams, but these are of higher value when compared to the larger teams of this study. It is also clear that the larger a team becomes, the more the trend is to focus on adopting new technologies to make their roles more efficient. This adoption is not however translated into outputs such as social capital but is translated into stronger networks and the formation of new networks. It is also clear that most negative factors around the UCS are related to the respondent’s hardware rather than the solution itself. Cost reductions because of virtuality will also be observed and using the Developed Framework as a blue print, an organisation should be able to observe direct benefits for an organisation by being able to confirm the thesis of this research in that having a UCS intervention is effective in supporting informal communication and collaboration in virtual teams.
- Full Text:
- Date Issued: 2020
Rethinking corporate social responsibility in the mining industry: focusing on recipients’ perspectives
- Authors: Hlatshwayo, Thina M
- Date: 2020
- Subjects: Social responsibility of business -- South Africa -- Case studies , Mining industries -- Social aspects-- South Africa , Sustainable developmenet -- Social aspects -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/141711 , vital:37998
- Description: Views on the importance of companies engaging in CSR initiatives have been debated widely and critics of the concept continue to argue both locally and globally. The objective of the study was to gain an in-depth understanding of the recipients’ perspectives on their involvement in CSR projects implemented in their community by a chosen mining company and the successes and challenges of the project. A qualitative research approach was used for the study. Using nonprobability purpose sampling, a total of 15 participants from Lusikisiki were selected for the study. The data obtained was analysed using inductive thematic analysis. The results of the study were discussed based on the three research questions of the study which focused on recipients’ perspectives on their involvement in the projects and their perceptions on the successes and challenges of the projects. The study found that the chosen mining company made a significant contribution towards developing the community. Furthermore, the study found that recipients’ involvement in the projects enabled them to realize their assets in one of the projects as a result of the shift in approach by the organisation as the project progressed (Needs Based Approach to ABCD Approach). In addition, the study found that the successes of the projects changed the recipients’ perceptions of themselves and enabled them to actively engage in transforming their lives. However, the projects did face many challenges and recipients posited that more still needs to be done by organisations to develop communities and ensure that projects remain sustainable long after their partnership has dissolved.
- Full Text:
- Date Issued: 2020
- Authors: Hlatshwayo, Thina M
- Date: 2020
- Subjects: Social responsibility of business -- South Africa -- Case studies , Mining industries -- Social aspects-- South Africa , Sustainable developmenet -- Social aspects -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/141711 , vital:37998
- Description: Views on the importance of companies engaging in CSR initiatives have been debated widely and critics of the concept continue to argue both locally and globally. The objective of the study was to gain an in-depth understanding of the recipients’ perspectives on their involvement in CSR projects implemented in their community by a chosen mining company and the successes and challenges of the project. A qualitative research approach was used for the study. Using nonprobability purpose sampling, a total of 15 participants from Lusikisiki were selected for the study. The data obtained was analysed using inductive thematic analysis. The results of the study were discussed based on the three research questions of the study which focused on recipients’ perspectives on their involvement in the projects and their perceptions on the successes and challenges of the projects. The study found that the chosen mining company made a significant contribution towards developing the community. Furthermore, the study found that recipients’ involvement in the projects enabled them to realize their assets in one of the projects as a result of the shift in approach by the organisation as the project progressed (Needs Based Approach to ABCD Approach). In addition, the study found that the successes of the projects changed the recipients’ perceptions of themselves and enabled them to actively engage in transforming their lives. However, the projects did face many challenges and recipients posited that more still needs to be done by organisations to develop communities and ensure that projects remain sustainable long after their partnership has dissolved.
- Full Text:
- Date Issued: 2020
An analysis of South Africa’s food security policy frameworks from a food sovereignty perspective: challenges and implications for genuine long-term food security
- Authors: Hoepfl, Jason
- Date: 2020
- Subjects: Food sovereignty -- South Africa , Food security -- South Africa , Food security -- Government policy -- South Africa , Food security -- Climatic factors -- South Africa , Food policy -- Government policy -- South Africa , Agriculture and state -- South Africa , Food industry and trade -- Government policy -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSocSci
- Identifier: http://hdl.handle.net/10962/162851 , vital:40990
- Description: Food price volatility, ecological shocks and unprecedented levels of hunger and obesity are increasing concerns within food security governance, as is the emergence of food sovereignty in broadening critical discussions around food, water, energy and environmental crises. This thesis analyses this changing terrain in the context of South African policy. It analyses shifts in policymaking and the capability of South Africa’s food security policy frameworks to include food sovereignty principles and in so doing support genuine long-term food security. A shift in policy priorities from household production, trade and income opportunities towards social safety nets and nutritional interventions is identified. This focus is constrained by an inability to affect structural changes within a deeply inequitable food landscape. An emphasis on commercial farming and unwillingness to challenge large agribusiness, value chains and corporate retail has enabled social differentiation in access to food and the country’s colonial land dispensation to continue. Consequently, markets have continued to be antipathetic to the needs of poor producers and consumers in South Africa. To overcome these structural constraints, food security policy needs to be framed within a more radical normative agenda. This is important for challenging inequitable power relations and asserting the social and ecological imperatives of healthy food systems. Food sovereignty has significant potential to support a normative agenda by supporting the multiple farming practices, enterprises and livelihood strategies pursued by poor farmers, the unemployed and working poor whilst preserving sensitive environments for future generations. Determining the future of food security is not the privilege of the few with economic clout or power to govern but the right of all. The incorporation of food sovereignty principles in policymaking is therefore paramount for achieving genuine long-term food security.
- Full Text:
- Date Issued: 2020
- Authors: Hoepfl, Jason
- Date: 2020
- Subjects: Food sovereignty -- South Africa , Food security -- South Africa , Food security -- Government policy -- South Africa , Food security -- Climatic factors -- South Africa , Food policy -- Government policy -- South Africa , Agriculture and state -- South Africa , Food industry and trade -- Government policy -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSocSci
- Identifier: http://hdl.handle.net/10962/162851 , vital:40990
- Description: Food price volatility, ecological shocks and unprecedented levels of hunger and obesity are increasing concerns within food security governance, as is the emergence of food sovereignty in broadening critical discussions around food, water, energy and environmental crises. This thesis analyses this changing terrain in the context of South African policy. It analyses shifts in policymaking and the capability of South Africa’s food security policy frameworks to include food sovereignty principles and in so doing support genuine long-term food security. A shift in policy priorities from household production, trade and income opportunities towards social safety nets and nutritional interventions is identified. This focus is constrained by an inability to affect structural changes within a deeply inequitable food landscape. An emphasis on commercial farming and unwillingness to challenge large agribusiness, value chains and corporate retail has enabled social differentiation in access to food and the country’s colonial land dispensation to continue. Consequently, markets have continued to be antipathetic to the needs of poor producers and consumers in South Africa. To overcome these structural constraints, food security policy needs to be framed within a more radical normative agenda. This is important for challenging inequitable power relations and asserting the social and ecological imperatives of healthy food systems. Food sovereignty has significant potential to support a normative agenda by supporting the multiple farming practices, enterprises and livelihood strategies pursued by poor farmers, the unemployed and working poor whilst preserving sensitive environments for future generations. Determining the future of food security is not the privilege of the few with economic clout or power to govern but the right of all. The incorporation of food sovereignty principles in policymaking is therefore paramount for achieving genuine long-term food security.
- Full Text:
- Date Issued: 2020
Sectoral co-integration and portfolio diversification benefits: a business cycle examination of South African equity sectors
- Authors: Hofisi, Tinashe S
- Date: 2020
- Subjects: Portfolio management -- South Africa , Investments -- South Africa , Investments, South African , Stocks -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/146379 , vital:38521
- Description: The onset of globalisation and simultaneous changes in financial technology and financial reforms dissipated hurdles once faced in financial transactions among stock markets. Hence, stock markets around the world became increasingly integrated because there was a free flow of cross border investments. Consequently, international diversification diminished thereby undermining the ability of investors to diversify investments across borders. For that reason, recent literature on portfolio diversification is urging investors to shift their focus to domestic portfolio diversification as an alternative. On that account, this study aims to examine the co-integration and dynamic causalities between South African equity market sectors in order to ascertain the sectoral diversification opportunities available to domestic investors over time. The study was examined over the different phases of the business cycle as well as the full sample, i.e. 2004 – 2018, with a view to shedding light on the inter-sectoral diversification opportunities of domestic investors over the South African business cycle. The phases of the business cycle applied are a| expansion and boom; b| recession and recovery phase and c| stagnation phase. The Johansen co-integration and Granger-causality tests were employed. The hypothesis of the study is that, if sectors are not cointegrated, then diversification benefits can be reaped by constructing a portfolio that combines stocks from the respective sectors. On the whole, the findings of this study show that there are both long-run and short-run diversification opportunities across the different phases of the South African business cycle as well as the full sample. However, there are lesser diversification opportunities in the recession and recovery phase over both the long-run and short-run. These results indicate that domestic sectoral portfolio diversification is least effective when it is needed the most (i.e. in a period of heightened volatility such as recession and recovery phase). This study will contribute to the existing literature in two ways; firstly, to investors who intend to diversify their portfolios domestically rather than internationally and, secondly, after reasonably thorough research it was evident that there is scant literature on domestic sectoral diversification in South Africa. As a result, the study attempts to address this gap. Additionally, the essence of the business cycle in this study is to make investors aware of potential diversification opportunities when positioning their portfolios for the next shift in the business cycle.
- Full Text:
- Date Issued: 2020
- Authors: Hofisi, Tinashe S
- Date: 2020
- Subjects: Portfolio management -- South Africa , Investments -- South Africa , Investments, South African , Stocks -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/146379 , vital:38521
- Description: The onset of globalisation and simultaneous changes in financial technology and financial reforms dissipated hurdles once faced in financial transactions among stock markets. Hence, stock markets around the world became increasingly integrated because there was a free flow of cross border investments. Consequently, international diversification diminished thereby undermining the ability of investors to diversify investments across borders. For that reason, recent literature on portfolio diversification is urging investors to shift their focus to domestic portfolio diversification as an alternative. On that account, this study aims to examine the co-integration and dynamic causalities between South African equity market sectors in order to ascertain the sectoral diversification opportunities available to domestic investors over time. The study was examined over the different phases of the business cycle as well as the full sample, i.e. 2004 – 2018, with a view to shedding light on the inter-sectoral diversification opportunities of domestic investors over the South African business cycle. The phases of the business cycle applied are a| expansion and boom; b| recession and recovery phase and c| stagnation phase. The Johansen co-integration and Granger-causality tests were employed. The hypothesis of the study is that, if sectors are not cointegrated, then diversification benefits can be reaped by constructing a portfolio that combines stocks from the respective sectors. On the whole, the findings of this study show that there are both long-run and short-run diversification opportunities across the different phases of the South African business cycle as well as the full sample. However, there are lesser diversification opportunities in the recession and recovery phase over both the long-run and short-run. These results indicate that domestic sectoral portfolio diversification is least effective when it is needed the most (i.e. in a period of heightened volatility such as recession and recovery phase). This study will contribute to the existing literature in two ways; firstly, to investors who intend to diversify their portfolios domestically rather than internationally and, secondly, after reasonably thorough research it was evident that there is scant literature on domestic sectoral diversification in South Africa. As a result, the study attempts to address this gap. Additionally, the essence of the business cycle in this study is to make investors aware of potential diversification opportunities when positioning their portfolios for the next shift in the business cycle.
- Full Text:
- Date Issued: 2020
Analysis of the regulation of HSP90α expression upon differentiation of C2C12 cells
- Authors: Holm, Nathan Christopher
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/163318 , vital:41028
- Description: Thesis (MSc)--Rhodes University, Faculty of Science, Biochemistry and Microbiology, 2020.
- Full Text:
- Date Issued: 2020
- Authors: Holm, Nathan Christopher
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/163318 , vital:41028
- Description: Thesis (MSc)--Rhodes University, Faculty of Science, Biochemistry and Microbiology, 2020.
- Full Text:
- Date Issued: 2020
“Savage” hair and mothers’ hearts: a corpus-based critical discourse analysis of intersectional identities in two South African school setworks
- Hubbard, Beatrice Elizabeth Anne
- Authors: Hubbard, Beatrice Elizabeth Anne
- Date: 2020
- Subjects: Women in literature , Women, Black in literature , Critical discourse analysis , Magona, Sindiwe -- Mother to mother , Bulbring, Edyth -- The Mark
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/141770 , vital:38003
- Description: This thesis reports on the discursive construal of intersectional physical identities, with particular reference to ‘black’ female characters, in two novels: Sindiwe Magona’s Mother to Mother, and Edyth Bulbring’s The Mark. These novels are prescribed for Grade 10 English Home Language learners in all South African public schools. Gendered identity construction in texts has been widely discussed in critical linguistics, with some research showing that the ways in which bodies are construed reveal the hegemonic and stereotypical gendering of men and women. However, these arguments have not adequately addressed the intersectional nature of identity construction. This thesis employs Corpus-based Critical Discourse Analysis to investigate the complex physical identities of, especially, ‘black’ female characters in these two novels. The inclusion of Corpus Linguistics is essential for uncovering hidden patterns of language choice, while the analytical techniques and theoretical notions from Critical Discourse Analysis provide the explanatory power that underpins the qualitative analysis. The uses to which nine key body parts are put reveal discourse prosodies showing different intersectional realisations for intimacy, power, violence, emotion, and racial marking. These discourse prosodies are most starkly realised in the two body parts, one from each novel, that are statistically most clearly linked to ‘black’ female characters. HAIR in The Mark is used variously as a racial marker, a target for racism, and a symbol for racial pride. HEART in Mother to Mother is used almost exclusively to symbolise the emotional pain of a mother’s love, and how empathy for another mother’s pain can bridge racial divides. Principal findings reveal that both novels provide very necessary lessons in cross-racial empathy, pride in ‘blackness,’ and interracial relationships. However, it is of concern that these novels also exhibit an over-valorisation of motherhood, largely stereotypical depictions of gender roles, and ableist language. In sum, both novels promote some of the transformative principles of the national curriculum, and are shown to have a bearing on nation building.
- Full Text:
- Date Issued: 2020
- Authors: Hubbard, Beatrice Elizabeth Anne
- Date: 2020
- Subjects: Women in literature , Women, Black in literature , Critical discourse analysis , Magona, Sindiwe -- Mother to mother , Bulbring, Edyth -- The Mark
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/141770 , vital:38003
- Description: This thesis reports on the discursive construal of intersectional physical identities, with particular reference to ‘black’ female characters, in two novels: Sindiwe Magona’s Mother to Mother, and Edyth Bulbring’s The Mark. These novels are prescribed for Grade 10 English Home Language learners in all South African public schools. Gendered identity construction in texts has been widely discussed in critical linguistics, with some research showing that the ways in which bodies are construed reveal the hegemonic and stereotypical gendering of men and women. However, these arguments have not adequately addressed the intersectional nature of identity construction. This thesis employs Corpus-based Critical Discourse Analysis to investigate the complex physical identities of, especially, ‘black’ female characters in these two novels. The inclusion of Corpus Linguistics is essential for uncovering hidden patterns of language choice, while the analytical techniques and theoretical notions from Critical Discourse Analysis provide the explanatory power that underpins the qualitative analysis. The uses to which nine key body parts are put reveal discourse prosodies showing different intersectional realisations for intimacy, power, violence, emotion, and racial marking. These discourse prosodies are most starkly realised in the two body parts, one from each novel, that are statistically most clearly linked to ‘black’ female characters. HAIR in The Mark is used variously as a racial marker, a target for racism, and a symbol for racial pride. HEART in Mother to Mother is used almost exclusively to symbolise the emotional pain of a mother’s love, and how empathy for another mother’s pain can bridge racial divides. Principal findings reveal that both novels provide very necessary lessons in cross-racial empathy, pride in ‘blackness,’ and interracial relationships. However, it is of concern that these novels also exhibit an over-valorisation of motherhood, largely stereotypical depictions of gender roles, and ableist language. In sum, both novels promote some of the transformative principles of the national curriculum, and are shown to have a bearing on nation building.
- Full Text:
- Date Issued: 2020
Developing social indicators for the evaluation of natural resource management programmes using a capability approach in the Eastern Cape, South Africa
- Authors: Human, Johanna Susanna
- Date: 2020
- Subjects: Environmental education -- South Africa -- Eastern Cape , Natural resources -- Management -- Study and teaching (Continuing education) -- South Africa -- Eastern Cape , Sustainable development -- Study and teaching (Continuing education) -- South Africa -- Eastern Cape , Environmental economics -- Study and teaching (Continuing education) -- South Africa -- Eastern Cape , Subsistence farming -- South Africa -- Eastern Cape , Watersheds -- South Africa -- Eastern Cape , Capabilities approach (Social sciences) , Tsitsa River Catchment (Eastern Cape, South Africa)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/147348 , vital:38628
- Description: The dissertation investigates how the capability approach can be used to develop social indicators for a natural resource management (NRM) programme. The study aimed to develop an understanding of what the beneficiaries of the programme value being and doing to guide the development of social indicators that will take into consideration their personal development aspirations. These valued beings and doings were then overlaid with the programme goals and objectives to identify and select the final indicators. The study was situated in the Tsitsa catchment in the Eastern Cape, South Africa and was part of a natural resource management programme, focused on land restoration and avoided degradation. Methods used to collect data for this study and develop an understanding of what the residents’ valued beings and doings were, included semi-structured interviews, workshops and document analysis. The research population was non-homogenous. I tried to include voices representing different prominent groups of land users in the study. This included established commercial farmers, emerging commercial farmers, commercial forestry, residents residing in communal areas and engaged with subsistence farming and residents from these communal areas who are now residing elsewhere but continue to have connections to the catchment. Understanding the voices of these different groups who reside in the catchment was important to develop an inclusive understanding of what residents of the catchment valued beings and doings were. The research process was supported by participatory approaches. This process, and the lessons learnt during the research process, were valuable for the further development and implementation of the planned participatory monitoring evaluation reflection and learning (PMERL) framework. The research process involved learning from the research participants about their valued beings and doings and what was important for the programme implementers. Some of the research participants from the Rhodes University implementation team (RUIT) were also involved in selecting the indicators they thought the programme should monitor. Overall, using the capability approach helped me to gain insight and understanding with regard to what the valued beings and doings are for the residents of the catchment and what they would like development programmes, such as the Tsitsa Project, to address. It was surprising to find many areas of overlap between the valued beings and doings of the different residents in the catchment, as well as the similarities between these and the goals and objectives of the Tsitsa Project. In conclusion, using the capability approach was useful to learn what was important for the residents of the catchment to help develop the social indicators but also to learn how to guide and steer participatory monitoring and evaluation processes in the future.
- Full Text:
- Date Issued: 2020
- Authors: Human, Johanna Susanna
- Date: 2020
- Subjects: Environmental education -- South Africa -- Eastern Cape , Natural resources -- Management -- Study and teaching (Continuing education) -- South Africa -- Eastern Cape , Sustainable development -- Study and teaching (Continuing education) -- South Africa -- Eastern Cape , Environmental economics -- Study and teaching (Continuing education) -- South Africa -- Eastern Cape , Subsistence farming -- South Africa -- Eastern Cape , Watersheds -- South Africa -- Eastern Cape , Capabilities approach (Social sciences) , Tsitsa River Catchment (Eastern Cape, South Africa)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/147348 , vital:38628
- Description: The dissertation investigates how the capability approach can be used to develop social indicators for a natural resource management (NRM) programme. The study aimed to develop an understanding of what the beneficiaries of the programme value being and doing to guide the development of social indicators that will take into consideration their personal development aspirations. These valued beings and doings were then overlaid with the programme goals and objectives to identify and select the final indicators. The study was situated in the Tsitsa catchment in the Eastern Cape, South Africa and was part of a natural resource management programme, focused on land restoration and avoided degradation. Methods used to collect data for this study and develop an understanding of what the residents’ valued beings and doings were, included semi-structured interviews, workshops and document analysis. The research population was non-homogenous. I tried to include voices representing different prominent groups of land users in the study. This included established commercial farmers, emerging commercial farmers, commercial forestry, residents residing in communal areas and engaged with subsistence farming and residents from these communal areas who are now residing elsewhere but continue to have connections to the catchment. Understanding the voices of these different groups who reside in the catchment was important to develop an inclusive understanding of what residents of the catchment valued beings and doings were. The research process was supported by participatory approaches. This process, and the lessons learnt during the research process, were valuable for the further development and implementation of the planned participatory monitoring evaluation reflection and learning (PMERL) framework. The research process involved learning from the research participants about their valued beings and doings and what was important for the programme implementers. Some of the research participants from the Rhodes University implementation team (RUIT) were also involved in selecting the indicators they thought the programme should monitor. Overall, using the capability approach helped me to gain insight and understanding with regard to what the valued beings and doings are for the residents of the catchment and what they would like development programmes, such as the Tsitsa Project, to address. It was surprising to find many areas of overlap between the valued beings and doings of the different residents in the catchment, as well as the similarities between these and the goals and objectives of the Tsitsa Project. In conclusion, using the capability approach was useful to learn what was important for the residents of the catchment to help develop the social indicators but also to learn how to guide and steer participatory monitoring and evaluation processes in the future.
- Full Text:
- Date Issued: 2020
Modelling and investigating primary beam effects of reflector antenna arrays
- Authors: Iheanetu, Kelachukwu
- Date: 2020
- Subjects: Antennas, Reflector , Radio telescopes , Astronomical instruments -- Calibration , Holography , Polynomials , Very large array telescopes -- South Africa , Astronomy -- Data processing , Primary beam effects , Jacobi-Bessel pattern , Cassbeam software , MeerKAT telescope
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/147425 , vital:38635
- Description: Signals received by a radio telescope are always affected by propagation and instrumental effects. These effects need to be modelled and accounted for during the process of calibration. The primary beam (PB) of the antenna is one major instrumental effect that needs to be accounted for during calibration. Producing accurate models of the radio antenna PB is crucial, and many approaches (like electromagnetic and optical simulations) have been used to model it. The cos³ function, Jacobi-Bessel pattern, characteristic basis function patterns (CBFP) and Cassbeam software (which uses optical ray-tracing with antenna parameters) have also been used to model it. These models capture the basic PB effects. Real-life PB patterns differ from these models due to various subtle effects such as mechanical deformation and effects introduced into the PB due to standing waves that exist in reflector antennas. The actual patterns can be measured via a process called astro-holography (or holography), but this is subject to noise, radio frequency interference, and other measurement errors. In our approach, we use principal component analysis and Zernike polynomials to model the PBs of the Very Large Array (VLA) and the MeerKAT telescopes from their holography measured data. The models have reconstruction errors of less than 5% at a compression factor of approximately 98% for both arrays. We also present steps that can be used to generate accurate beam models for any telescope (independent of its design) based on holography measured data. Analysis of the VLA measured PBs revealed that the graph of the beam sizes (and centre offset positions) have a fast oscillating trend (superimposed on a slow trend) with frequency. This spectral behaviour we termed ripple or characteristic effects. Most existing PB models that are used in calibrating VLA data do not incorporate these direction dependent effects (DDEs). We investigate the impact of using PB models that ignore this DDE in continuum calibration and imaging via simulations. Our experiments show that, although these effects translate into less than 10% errors in source flux recovery, they do lead to 30% reduction in the dynamic range. To prepare data for Hi and radio halo (faint emissions) science analysis requires carrying out foreground subtraction of bright (continuum) sources. We investigate the impact of using beam models that ignore these ripple effects during continuum subtraction. These show that using PB models which completely ignore the ripple effects in continuum subtraction could translate to error of more to 30% in the recovered Hi spectral properties. This implies that science inferences drawn from the results for Hi studies could have errors of the same magnitude.
- Full Text:
- Date Issued: 2020
- Authors: Iheanetu, Kelachukwu
- Date: 2020
- Subjects: Antennas, Reflector , Radio telescopes , Astronomical instruments -- Calibration , Holography , Polynomials , Very large array telescopes -- South Africa , Astronomy -- Data processing , Primary beam effects , Jacobi-Bessel pattern , Cassbeam software , MeerKAT telescope
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/147425 , vital:38635
- Description: Signals received by a radio telescope are always affected by propagation and instrumental effects. These effects need to be modelled and accounted for during the process of calibration. The primary beam (PB) of the antenna is one major instrumental effect that needs to be accounted for during calibration. Producing accurate models of the radio antenna PB is crucial, and many approaches (like electromagnetic and optical simulations) have been used to model it. The cos³ function, Jacobi-Bessel pattern, characteristic basis function patterns (CBFP) and Cassbeam software (which uses optical ray-tracing with antenna parameters) have also been used to model it. These models capture the basic PB effects. Real-life PB patterns differ from these models due to various subtle effects such as mechanical deformation and effects introduced into the PB due to standing waves that exist in reflector antennas. The actual patterns can be measured via a process called astro-holography (or holography), but this is subject to noise, radio frequency interference, and other measurement errors. In our approach, we use principal component analysis and Zernike polynomials to model the PBs of the Very Large Array (VLA) and the MeerKAT telescopes from their holography measured data. The models have reconstruction errors of less than 5% at a compression factor of approximately 98% for both arrays. We also present steps that can be used to generate accurate beam models for any telescope (independent of its design) based on holography measured data. Analysis of the VLA measured PBs revealed that the graph of the beam sizes (and centre offset positions) have a fast oscillating trend (superimposed on a slow trend) with frequency. This spectral behaviour we termed ripple or characteristic effects. Most existing PB models that are used in calibrating VLA data do not incorporate these direction dependent effects (DDEs). We investigate the impact of using PB models that ignore this DDE in continuum calibration and imaging via simulations. Our experiments show that, although these effects translate into less than 10% errors in source flux recovery, they do lead to 30% reduction in the dynamic range. To prepare data for Hi and radio halo (faint emissions) science analysis requires carrying out foreground subtraction of bright (continuum) sources. We investigate the impact of using beam models that ignore these ripple effects during continuum subtraction. These show that using PB models which completely ignore the ripple effects in continuum subtraction could translate to error of more to 30% in the recovered Hi spectral properties. This implies that science inferences drawn from the results for Hi studies could have errors of the same magnitude.
- Full Text:
- Date Issued: 2020
Technology in conservation: towards a system for in-field drone detection of invasive vegetation
- James, Katherine Margaret Frances
- Authors: James, Katherine Margaret Frances
- Date: 2020
- Subjects: Drone aircraft in remote sensing , Neural networks (Computer science) , Drone aircraft in remote sensing -- Case studies , Machine learning , Computer vision , Environmental monitoring -- Remote sensing , Invasive plants -- Monitoring
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/143408 , vital:38244
- Description: Remote sensing can assist in monitoring the spread of invasive vegetation. The adoption of camera-carrying unmanned aerial vehicles, commonly referred to as drones, as remote sensing tools has yielded images of higher spatial resolution than traditional techniques. Drones also have the potential to interact with the environment through the delivery of bio-control or herbicide, as seen with their adoption in precision agriculture. Unlike in agricultural applications, however, invasive plants do not have a predictable position relative to each other within the environment. To facilitate the adoption of drones as an environmental monitoring and management tool, drones need to be able to intelligently distinguish between invasive and non-invasive vegetation on the fly. In this thesis, we present the augmentation of a commercially available drone with a deep machine learning model to investigate the viability of differentiating between an invasive shrub and other vegetation. As a case study, this was applied to the shrub genus Hakea, originating in Australia and invasive in several countries including South Africa. However, for this research, the methodology is important, rather than the chosen target plant. A dataset was collected using the available drone and manually annotated to facilitate the supervised training of the model. Two approaches were explored, namely, classification and semantic segmentation. For each of these, several models were trained and evaluated to find the optimal one. The chosen model was then interfaced with the drone via an Android application on a mobile device and its performance was preliminarily evaluated in the field. Based on these findings, refinements were made and thereafter a thorough field evaluation was performed to determine the best conditions for model operation. Results from the classification task show that deep learning models are capable of distinguishing between target and other shrubs in ideal candidate windows. However, classification in this manner is restricted by the proposal of such candidate windows. End-to-end image segmentation using deep learning overcomes this problem, classifying the image in a pixel-wise manner. Furthermore, the use of appropriate loss functions was found to improve model performance. Field tests show that illumination and shadow pose challenges to the model, but that good recall can be achieved when the conditions are ideal. False positive detection remains an issue that could be improved. This approach shows the potential for drones as an environmental monitoring and management tool when coupled with deep machine learning techniques and outlines potential problems that may be encountered.
- Full Text:
- Date Issued: 2020
- Authors: James, Katherine Margaret Frances
- Date: 2020
- Subjects: Drone aircraft in remote sensing , Neural networks (Computer science) , Drone aircraft in remote sensing -- Case studies , Machine learning , Computer vision , Environmental monitoring -- Remote sensing , Invasive plants -- Monitoring
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/143408 , vital:38244
- Description: Remote sensing can assist in monitoring the spread of invasive vegetation. The adoption of camera-carrying unmanned aerial vehicles, commonly referred to as drones, as remote sensing tools has yielded images of higher spatial resolution than traditional techniques. Drones also have the potential to interact with the environment through the delivery of bio-control or herbicide, as seen with their adoption in precision agriculture. Unlike in agricultural applications, however, invasive plants do not have a predictable position relative to each other within the environment. To facilitate the adoption of drones as an environmental monitoring and management tool, drones need to be able to intelligently distinguish between invasive and non-invasive vegetation on the fly. In this thesis, we present the augmentation of a commercially available drone with a deep machine learning model to investigate the viability of differentiating between an invasive shrub and other vegetation. As a case study, this was applied to the shrub genus Hakea, originating in Australia and invasive in several countries including South Africa. However, for this research, the methodology is important, rather than the chosen target plant. A dataset was collected using the available drone and manually annotated to facilitate the supervised training of the model. Two approaches were explored, namely, classification and semantic segmentation. For each of these, several models were trained and evaluated to find the optimal one. The chosen model was then interfaced with the drone via an Android application on a mobile device and its performance was preliminarily evaluated in the field. Based on these findings, refinements were made and thereafter a thorough field evaluation was performed to determine the best conditions for model operation. Results from the classification task show that deep learning models are capable of distinguishing between target and other shrubs in ideal candidate windows. However, classification in this manner is restricted by the proposal of such candidate windows. End-to-end image segmentation using deep learning overcomes this problem, classifying the image in a pixel-wise manner. Furthermore, the use of appropriate loss functions was found to improve model performance. Field tests show that illumination and shadow pose challenges to the model, but that good recall can be achieved when the conditions are ideal. False positive detection remains an issue that could be improved. This approach shows the potential for drones as an environmental monitoring and management tool when coupled with deep machine learning techniques and outlines potential problems that may be encountered.
- Full Text:
- Date Issued: 2020
Perceptions of the sugar-sweetened beverage tax in South Africa: a comparative study
- Jankeeparsad, Thanesha Reddy
- Authors: Jankeeparsad, Thanesha Reddy
- Date: 2020
- Subjects: Soft drinks -- Taxation -- South Africa , Carbonated drinks -- Taxation -- South Africa , Soft drinks -- Health aspects , College students -- South Africa -- Attitudes
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/142324 , vital:38070
- Description: This exploratory, comparative study aimed to investigate perceptions of the participants in the study in South Africa regarding the tax on sugar-sweetened beverages. The study further aimed to compare these perceptions with perceptions identified in selected foreign jurisdictions that have levied the tax on sugar-sweetened beverages. A voluntary, paper-based, anonymous survey questionnaire that included both closed- and open-ended questions was selected as the primary method of data collection. This questionnaire was administered to post-graduate Bachelor of Commerce Accounting and Postgraduate Diploma in Accounting students, aged twenty-one years and older, studying at three residential universities in South Africa, during the 2018 academic year. An extensive analysis of literature available on sugar-sweetened beverage taxes, both locally and internationally, was conducted. The two main constructs (construct 1: perception of the sugar-sweetened beverage tax and the price of sugar-sweetened beverages and construct 2: the social impact of the sugarsweetened beverage tax) were then analysed using descriptive statistics. This study found that there is a significant association between gender and perception that the sugary beverage levy will be beneficial to health, with female perceptions of the benefit of the sugary beverage levy being greater than that of males. Respondents appear to have a positive perception of the sugary beverages levy, understand the sugary beverage levy, as well as the health benefits that will be derived from the levy. Respondents supported the tax on sugar-sweetened beverages if the revenue generated was used to improve the health care system and if the price of healthy foods decreased. Female respondents were found to drink fewer sugarsweetened beverages than male respondents, but females reported higher sugar-sweetened beverage consumption during stressful periods. The current study can possibly provide policy makers with more information regarding acceptance of the sugar-sweetened beverage tax and shape guidelines for future amendments of the tax imposed.
- Full Text:
- Date Issued: 2020
- Authors: Jankeeparsad, Thanesha Reddy
- Date: 2020
- Subjects: Soft drinks -- Taxation -- South Africa , Carbonated drinks -- Taxation -- South Africa , Soft drinks -- Health aspects , College students -- South Africa -- Attitudes
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/142324 , vital:38070
- Description: This exploratory, comparative study aimed to investigate perceptions of the participants in the study in South Africa regarding the tax on sugar-sweetened beverages. The study further aimed to compare these perceptions with perceptions identified in selected foreign jurisdictions that have levied the tax on sugar-sweetened beverages. A voluntary, paper-based, anonymous survey questionnaire that included both closed- and open-ended questions was selected as the primary method of data collection. This questionnaire was administered to post-graduate Bachelor of Commerce Accounting and Postgraduate Diploma in Accounting students, aged twenty-one years and older, studying at three residential universities in South Africa, during the 2018 academic year. An extensive analysis of literature available on sugar-sweetened beverage taxes, both locally and internationally, was conducted. The two main constructs (construct 1: perception of the sugar-sweetened beverage tax and the price of sugar-sweetened beverages and construct 2: the social impact of the sugarsweetened beverage tax) were then analysed using descriptive statistics. This study found that there is a significant association between gender and perception that the sugary beverage levy will be beneficial to health, with female perceptions of the benefit of the sugary beverage levy being greater than that of males. Respondents appear to have a positive perception of the sugary beverages levy, understand the sugary beverage levy, as well as the health benefits that will be derived from the levy. Respondents supported the tax on sugar-sweetened beverages if the revenue generated was used to improve the health care system and if the price of healthy foods decreased. Female respondents were found to drink fewer sugarsweetened beverages than male respondents, but females reported higher sugar-sweetened beverage consumption during stressful periods. The current study can possibly provide policy makers with more information regarding acceptance of the sugar-sweetened beverage tax and shape guidelines for future amendments of the tax imposed.
- Full Text:
- Date Issued: 2020
Unravelling the replication biology of Providence virus in a cell culturebased model system
- Authors: Jarvie, Rachel Anne
- Date: 2020
- Subjects: Virology -- Research , RNA viruses , Viruses -- Reproduction , Providence virus
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/142339 , vital:38071
- Description: There has been an increase in the number of viral outbreaks in the last decade; the majority of these are attributed to insect-human or animal-human transfer. Despite this awareness, there is limited understanding of the replication biology of the viruses causing the outbreaks and there are few model systems that are available to study RNA virus replication and viral persistence. In this study, we describe a Providence (PrV)-based model system to study virus replication biology. PrV is a single-stranded RNA virus that can cross Kingdom boundaries; it is capable of establishing a productive infection in insect and mammalian cell culture and it is also capable of replicating in plants. Only one other virus has been reported to infect a similar host range - the Nodavirus, Flock House virus (FHV). First, we performed a bioinformatic analysis of the PrV genome and validated the tools that were currently available to work with this model system in mammalian cells. Our data indicate that PrV infection of human cervical cancer (HeLa) cells results in the production of p130, p104/p40 and VCAP, albeit at low levels. While PrV replication in insect cells is associated with the Golgi apparatus and secretory vesicles, in HeLa cells, PrV replication is associated with the mitochondria. It is interesting to note that FHV replication factories are located on the outer mitochondrial membrane. In an attempt to study PrV virus replication in vitro, we adapted the BioID system reported by Roux et al. (2012). Here a promiscuous biotin ligase enzyme (BirA) was fused to a protein of interest and the expression of the fusion protein in mammalian cells resulted in the proximitybased biotinylation of proteins associated with the protein of interest. Using p40 as the protein of interest, we studied the fusion protein (BirA-p40) in transiently transfected HeLa cells and in a stable cell line, using western blot analysis and confocal microscopy. We faced challenges comparing the data collected using the two antibody-based detection techniques and the lack of BirA-p40 detection when using western analysis was attributed to the associated of p40 with detergent resistant membranes. BirA-p40 was subsequently expressed using in vitro coupled transcription/translation reactions, in the presence of excess biotin. While BirA-p40 was robustly expressed under these conditions, biotinylation of BirA-p40 was not detected. We attributed this to the conditions used in the experiments and given additional time, we would extend the duration of biotinylation, in vitro. PrV replication in mammalian cells was detectable using confocal microscopy however the levels of fluorescence were relatively low. The knowledge that p40 was associated with detergent resistant membranes led us to question the impact of detergent treatment of live cells on the detection of PrV replication. PrV-infected HeLa cells were treated with detergents with varying biochemical characteristics and the impact of these treatments on the detection of PrV replication were evaluated. We observed that linear and non-ionic detergents, namely NP-40 and Triton X-100, were most effective at enhancing the detection of viral replication in PrV-infected HeLa cells. Our data confirm that detergent treatment results in enhanced detection, and not enhanced PrV replication, in HeLa cells. Using the stable BirA-p40 expressing HeLa cell line, we showed that the protein is associated with membranes in vitro, and that the enhanced expression of BirA-p40 results in the formation of greater volumes of detergent-resistant membranes. In addition, detergent treatment of unfixed PrV-infected HeLa cells revealed the presence of the PrV p40 protein in the nucleoli of the cells. This is the first report of PrV proteins, which are translated in the cytosol of the mammalian cells, occurring in the nucleus. Our study has resulted in a deeper understanding of PrV replication in mammalian cell lines. A ‘simple RNA virus’ with only three predicted open reading frames has exhibited high levels of complexity within its elegant simplicity. This study has also highlighted the challenges associated with studying RNA virus replication biology in vitro. Looking forward, the identification of detergent-based enhancement for the detection of PrV replication provides the opportunity to perform more targeted PrV replication studies. The PrV-based model system can also be applied to the identification and analysis of potential broad-spectrum antiviral drugs in vitro. The latter application is particularly relevant considering the increase in the number of viral outbreaks over the last decade.
- Full Text:
- Date Issued: 2020
- Authors: Jarvie, Rachel Anne
- Date: 2020
- Subjects: Virology -- Research , RNA viruses , Viruses -- Reproduction , Providence virus
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/142339 , vital:38071
- Description: There has been an increase in the number of viral outbreaks in the last decade; the majority of these are attributed to insect-human or animal-human transfer. Despite this awareness, there is limited understanding of the replication biology of the viruses causing the outbreaks and there are few model systems that are available to study RNA virus replication and viral persistence. In this study, we describe a Providence (PrV)-based model system to study virus replication biology. PrV is a single-stranded RNA virus that can cross Kingdom boundaries; it is capable of establishing a productive infection in insect and mammalian cell culture and it is also capable of replicating in plants. Only one other virus has been reported to infect a similar host range - the Nodavirus, Flock House virus (FHV). First, we performed a bioinformatic analysis of the PrV genome and validated the tools that were currently available to work with this model system in mammalian cells. Our data indicate that PrV infection of human cervical cancer (HeLa) cells results in the production of p130, p104/p40 and VCAP, albeit at low levels. While PrV replication in insect cells is associated with the Golgi apparatus and secretory vesicles, in HeLa cells, PrV replication is associated with the mitochondria. It is interesting to note that FHV replication factories are located on the outer mitochondrial membrane. In an attempt to study PrV virus replication in vitro, we adapted the BioID system reported by Roux et al. (2012). Here a promiscuous biotin ligase enzyme (BirA) was fused to a protein of interest and the expression of the fusion protein in mammalian cells resulted in the proximitybased biotinylation of proteins associated with the protein of interest. Using p40 as the protein of interest, we studied the fusion protein (BirA-p40) in transiently transfected HeLa cells and in a stable cell line, using western blot analysis and confocal microscopy. We faced challenges comparing the data collected using the two antibody-based detection techniques and the lack of BirA-p40 detection when using western analysis was attributed to the associated of p40 with detergent resistant membranes. BirA-p40 was subsequently expressed using in vitro coupled transcription/translation reactions, in the presence of excess biotin. While BirA-p40 was robustly expressed under these conditions, biotinylation of BirA-p40 was not detected. We attributed this to the conditions used in the experiments and given additional time, we would extend the duration of biotinylation, in vitro. PrV replication in mammalian cells was detectable using confocal microscopy however the levels of fluorescence were relatively low. The knowledge that p40 was associated with detergent resistant membranes led us to question the impact of detergent treatment of live cells on the detection of PrV replication. PrV-infected HeLa cells were treated with detergents with varying biochemical characteristics and the impact of these treatments on the detection of PrV replication were evaluated. We observed that linear and non-ionic detergents, namely NP-40 and Triton X-100, were most effective at enhancing the detection of viral replication in PrV-infected HeLa cells. Our data confirm that detergent treatment results in enhanced detection, and not enhanced PrV replication, in HeLa cells. Using the stable BirA-p40 expressing HeLa cell line, we showed that the protein is associated with membranes in vitro, and that the enhanced expression of BirA-p40 results in the formation of greater volumes of detergent-resistant membranes. In addition, detergent treatment of unfixed PrV-infected HeLa cells revealed the presence of the PrV p40 protein in the nucleoli of the cells. This is the first report of PrV proteins, which are translated in the cytosol of the mammalian cells, occurring in the nucleus. Our study has resulted in a deeper understanding of PrV replication in mammalian cell lines. A ‘simple RNA virus’ with only three predicted open reading frames has exhibited high levels of complexity within its elegant simplicity. This study has also highlighted the challenges associated with studying RNA virus replication biology in vitro. Looking forward, the identification of detergent-based enhancement for the detection of PrV replication provides the opportunity to perform more targeted PrV replication studies. The PrV-based model system can also be applied to the identification and analysis of potential broad-spectrum antiviral drugs in vitro. The latter application is particularly relevant considering the increase in the number of viral outbreaks over the last decade.
- Full Text:
- Date Issued: 2020
Investigating conceptual teaching of word problems through visualisation processes: a case of selected Grad 9 mathematics teachers
- Authors: John, Ssennyomo Bernard
- Date: 2020
- Subjects: Mathematics -- Study and teaching (Secondary) -- South Africa , Pythagorean theorem -- Study and teaching (Secondary) , Mathematics teachers -- South Africa , Visualization
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/167497 , vital:41486
- Description: This study investigated how selected grade 9 mathematics teachers used visualisation strategies to conceptually teach Pythagoras' theorem word problems as a result of an intervention program. This research project is an integral component of the ViProMaths project whose goal is to research the effective use of visualisation strategies in the mathematics classroom in the Southern African region. This case study of mathematics teachers in the John Taolo Gaetsewe (JTG) District in the Northern Cape Province, used a social constructivist theory. The study is grounded within an interpretive paradigm and used an explanatory sequential mixed methods design. It surveyed eighty-seven mathematics teachers from all the secondary schools in the JTG District, focusing on their experiences when using visualisation approaches to teach Pythagoras’ theorem word problems. After the survey, three teachers purposively selected from three different schools in the district took part in the intervention programme. I used a survey questionnaire, classroom observations and interviews to collect the data from the study participants. The data were analysed quantitatively and qualitatively. The findings from survey data revealed that while teachers in the JTG District acknowledge the importance and value of visualisation strategies in the teaching of Pythagoras’ theorem word problems, many of them are either using visuals minimally or not using them at all. Challenges such as lack of resources in schools, time constrains, a lack of support from subject advisers, among others were noted. This thus necessitated a need for an intervention with some teachers in the district, specifically focusing on the use of visualisation tools and skills to teach Pythagoras’ theorem word problems for conceptual understanding. Lessons observations showed that all observed teachers used visual models to generate images and used the models to develop mathematical ideas. The teachers used the images to create platforms for classroom discussions. The discussions were driven by questions which teachers asked both for ascertaining learners’ prior knowledge and for finding out if they understood what the teachers were teaching. Interviews revealed that teachers’ perceptions had changed because they now know how to make and use different models to build on learners’ prior knowledge, extend what they are teaching to real life and make sense of Pythagoras’ proposition in multiple ways and to establish connections among a rich set of mathematics concepts when teaching Pythagoras’ theorem word problems. This study concludes that the use of visual strategies has the potential of enhancing conceptual teaching of Pythagoras’ theorem word problems. The implications for teachers are that learners need to be taught how to create visual representations (both internally and externally) of the relations between objects in a word problem as this will help them in maximising understanding. Furthermore, it is hoped that the results of this study could be used by various stake holders who include inter alia, mathematics subject advisers and teacher training institutions to improve the teaching of Pythagoras’ theorem word problems.
- Full Text:
- Date Issued: 2020
- Authors: John, Ssennyomo Bernard
- Date: 2020
- Subjects: Mathematics -- Study and teaching (Secondary) -- South Africa , Pythagorean theorem -- Study and teaching (Secondary) , Mathematics teachers -- South Africa , Visualization
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/167497 , vital:41486
- Description: This study investigated how selected grade 9 mathematics teachers used visualisation strategies to conceptually teach Pythagoras' theorem word problems as a result of an intervention program. This research project is an integral component of the ViProMaths project whose goal is to research the effective use of visualisation strategies in the mathematics classroom in the Southern African region. This case study of mathematics teachers in the John Taolo Gaetsewe (JTG) District in the Northern Cape Province, used a social constructivist theory. The study is grounded within an interpretive paradigm and used an explanatory sequential mixed methods design. It surveyed eighty-seven mathematics teachers from all the secondary schools in the JTG District, focusing on their experiences when using visualisation approaches to teach Pythagoras’ theorem word problems. After the survey, three teachers purposively selected from three different schools in the district took part in the intervention programme. I used a survey questionnaire, classroom observations and interviews to collect the data from the study participants. The data were analysed quantitatively and qualitatively. The findings from survey data revealed that while teachers in the JTG District acknowledge the importance and value of visualisation strategies in the teaching of Pythagoras’ theorem word problems, many of them are either using visuals minimally or not using them at all. Challenges such as lack of resources in schools, time constrains, a lack of support from subject advisers, among others were noted. This thus necessitated a need for an intervention with some teachers in the district, specifically focusing on the use of visualisation tools and skills to teach Pythagoras’ theorem word problems for conceptual understanding. Lessons observations showed that all observed teachers used visual models to generate images and used the models to develop mathematical ideas. The teachers used the images to create platforms for classroom discussions. The discussions were driven by questions which teachers asked both for ascertaining learners’ prior knowledge and for finding out if they understood what the teachers were teaching. Interviews revealed that teachers’ perceptions had changed because they now know how to make and use different models to build on learners’ prior knowledge, extend what they are teaching to real life and make sense of Pythagoras’ proposition in multiple ways and to establish connections among a rich set of mathematics concepts when teaching Pythagoras’ theorem word problems. This study concludes that the use of visual strategies has the potential of enhancing conceptual teaching of Pythagoras’ theorem word problems. The implications for teachers are that learners need to be taught how to create visual representations (both internally and externally) of the relations between objects in a word problem as this will help them in maximising understanding. Furthermore, it is hoped that the results of this study could be used by various stake holders who include inter alia, mathematics subject advisers and teacher training institutions to improve the teaching of Pythagoras’ theorem word problems.
- Full Text:
- Date Issued: 2020