The origin of endorheic pans on the African erosion surface North of Grahamstown, South Africa
- Authors: Alistoun, Judith Robyn
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4775 , http://hdl.handle.net/10962/d1011048
- Description: Pans on the African Erosion Surface near Grahamstown are small features, which, perhaps due to their small size have been neglected by researchers. From the outset the striking difference of these pans relative to other pans in southern Africa, is that the host rock is silcrete, a highly resistant rock well known as being associated with deeply weathered plateaus. The dominant origin theory for pans in southern Africa was developed by Goudie and Thomas (1985), and focuses on mechanisms relating to erosion and deflation. This model does not fit in well with the pans that have formed on substrate that has largely been unaffected by erosion in recent geological history (thousands to 10 000 years). As such this study examined the role of prolonged chemical weathering of Dwyka Tillite, that has led to the formation of silcrete. The hypothesis was that such deep weathering is responsible for local scale volume changes, which have in turn led to the formation of a depression. The centre of the pan indicated the highest concentration of Al₂O₃ and kaolinite at mid depths, and their concentrations decreased vertically away from these depths, and laterally towards the margins of the pan. Similar results were noted for SiO₂, while CaO and MgO (and calcite and dolomite) were highest at mid depths along the margins of the pan, and decreased laterally toward the centre of the pan. Results indicated that there was a positive relationship in the centre of the pan between: - the degree of chemical weathering and volume losses, - relative elevation of the pan and volume changes. Geochemically and mineralogically, there was a link between the high concentrations of Ca and Mg carbonates and volume gains in the margin of the pans. It is proposed that transpiration of vegetation along the margin of the pan caused the lateral movement of solutes, and the selective exclusion of these solutes by plants was associated with carbonate precipitation, leading to the creation of local relief. These results provide evidence to suggest that weathering and precipitation processes occurring over geological time scales are responsible for minor scale relief features, whose origin has been mistakenly attributed to deflation processes occurring over hundreds to thousands of years.
- Full Text:
- Date Issued: 2014
- Authors: Alistoun, Judith Robyn
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4775 , http://hdl.handle.net/10962/d1011048
- Description: Pans on the African Erosion Surface near Grahamstown are small features, which, perhaps due to their small size have been neglected by researchers. From the outset the striking difference of these pans relative to other pans in southern Africa, is that the host rock is silcrete, a highly resistant rock well known as being associated with deeply weathered plateaus. The dominant origin theory for pans in southern Africa was developed by Goudie and Thomas (1985), and focuses on mechanisms relating to erosion and deflation. This model does not fit in well with the pans that have formed on substrate that has largely been unaffected by erosion in recent geological history (thousands to 10 000 years). As such this study examined the role of prolonged chemical weathering of Dwyka Tillite, that has led to the formation of silcrete. The hypothesis was that such deep weathering is responsible for local scale volume changes, which have in turn led to the formation of a depression. The centre of the pan indicated the highest concentration of Al₂O₃ and kaolinite at mid depths, and their concentrations decreased vertically away from these depths, and laterally towards the margins of the pan. Similar results were noted for SiO₂, while CaO and MgO (and calcite and dolomite) were highest at mid depths along the margins of the pan, and decreased laterally toward the centre of the pan. Results indicated that there was a positive relationship in the centre of the pan between: - the degree of chemical weathering and volume losses, - relative elevation of the pan and volume changes. Geochemically and mineralogically, there was a link between the high concentrations of Ca and Mg carbonates and volume gains in the margin of the pans. It is proposed that transpiration of vegetation along the margin of the pan caused the lateral movement of solutes, and the selective exclusion of these solutes by plants was associated with carbonate precipitation, leading to the creation of local relief. These results provide evidence to suggest that weathering and precipitation processes occurring over geological time scales are responsible for minor scale relief features, whose origin has been mistakenly attributed to deflation processes occurring over hundreds to thousands of years.
- Full Text:
- Date Issued: 2014
The perceived visual impacts and attitudes of the Grahamstown community towards the Waainek Wind-Farm
- Authors: Cruickshank, Kyle Mark
- Date: 2014
- Subjects: Renewable energy sources -- South Africa -- Grahamstown Wind power plants -- South Africa -- Grahamstown -- Public opinion Wind power plants -- Social aspects -- South Africa -- Grahamstown Wind power plants -- Environmental aspects -- South Africa -- Grahamstown Wind power plants -- Economic aspects -- South Africa Wind turbines -- South Africa
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:1085 , http://hdl.handle.net/10962/d1011768
- Description: Renewable energy has become an important feature of most modern economies with clean and non-exhaustible sources of power being given a greater significance. Wind energy is one of the favoured renewable, as it is (2013) generally the cheapest and most mature technology available for commercial use. The South African government, as outlined by the Department of Energy's Integrated Resource Plan (IRP), aims to install 5 GW (Gigawatts) of wind energy by 2020. However, South Africa has had little experience in the wind energy industry which is limited to two projects, Klipheuwel (2002) and Darling (2008). Much effort has been dedicated to calculating balance sheet costs, which carries uncertainty due to the high reliance on country specific and site specific variables. An aspect which deserves more attention, and is often ignored, is the public‟s attitudes towards local wind farm developments, which have been known to "make or break" a project during the planning stages. Public backlashes have mostly been concerned with the visual "intrusiveness" of wind farms in the landscape. Detrimental effects on scenery, while seemingly innocuous, are acknowledged as being the single largest barrier to successful wind farm development. Individuals within an area become sentimentally attached to their surroundings, where significant rapid changes in the landscape are viewed as "damage". Economics recognises such declines in scenic resources as market failures, where an externalised cost is passed on to the public and is often not accounted for by private parties responsible for the liability. The primary objective therefore was to measure the magnitude of the visual impact, caused by the Waainek Wind Farm, on the Grahamstown community. Conventional NIMBY¹ (not in my back yard) reasoning, which seeks to explain local wind farm resistance, has attracted criticism with regard to its simplistic approach to wind farm problem identification. Contemporary arguments propose that NIMBY is a poor explanation for the trouble experienced on the local level because it groups problems into one all-encompassing term, leaving much of the discontent unexplained. Instead, the NIMBY explanation is really a broad set of unattended problems, largely resulting from the unsound practices present in the public participation process. Insufficient community involvement and disparities in the negotiation power structures have become the recent focus in wind farm literature. Essentially, these disparities force opposition groups to select factors which may seem more serious to developers, leading to ineffective remedial measures because the core underlying problems are not being remedied. Thus these considerations formed an additional area of investigation. No NIMBY effect was found for the Grahamstown community, as support for both the local and general level was roughly 80%. The public participation process on the other hand revealed that while many found the practices of the developer to be unfair, attitudes towards the wind farm were not adversely affected, especially for the lower income Grahamstown East areas. While the public participation process in this instance did not have any effect on people’s attitudes, careful inspection of the circumstances need to be given. Wind farms are new to South Africa, where the novelty and benefits are the focus of enthusiasm. Job opportunities as well as clean energy are positive drivers for attitudes; however given time, once the anticipation for wind farms dulls, real problems may be revealed. Thus it is crucial to implement good practice procedures during the public participation process, especially when national adoption rates of wind energy are low. Early implementation of an effective public participation process system will ensure that when major problems do arise in future projects, experience and institutional processes would have had ample opportunity to evolve appropriately over a period of time. The double bounded Contingent Valuation Method was used to value the impact of the wind farm on the Waainek scenery through a hypothetical scenario based procedure which presented pictures of the landscape before and after the wind farm had been installed. Based on the perceived impact of the wind farm, respondents were asked their Willingness to Pay to relocate the development, based solely on visual impacts. Learning design Contingent Valuation (Bateman et al., 2008) is a novel technique employed to familiarize respondents with the hypothetical market institution as well as the scenic goods being valued. Average Willingness to Pay was found to be R67 per month, with a final total monthly negative visual impact of R104,000 to R121,000 per month for the entire Grahamstown community. Grahamstown Central (middle-high income) residents were more likely to pay than Grahamstown East (low-middle income) East residents because of socio-economic differences present in each area. A ranking exercise determined that while negative visual impacts are present, the overall benefits derived from the wind farm are potentially much higher. Additionally, positive scenic improvements were found, but were not measured due to time constraints, and would have worked to reduce the net visual impact of the Waainek Wind Farm. ¹Problem where individuals support the general concept of wind power, but when it comes to local implementation, opposition to the development arises within the same group.
- Full Text:
- Date Issued: 2014
- Authors: Cruickshank, Kyle Mark
- Date: 2014
- Subjects: Renewable energy sources -- South Africa -- Grahamstown Wind power plants -- South Africa -- Grahamstown -- Public opinion Wind power plants -- Social aspects -- South Africa -- Grahamstown Wind power plants -- Environmental aspects -- South Africa -- Grahamstown Wind power plants -- Economic aspects -- South Africa Wind turbines -- South Africa
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:1085 , http://hdl.handle.net/10962/d1011768
- Description: Renewable energy has become an important feature of most modern economies with clean and non-exhaustible sources of power being given a greater significance. Wind energy is one of the favoured renewable, as it is (2013) generally the cheapest and most mature technology available for commercial use. The South African government, as outlined by the Department of Energy's Integrated Resource Plan (IRP), aims to install 5 GW (Gigawatts) of wind energy by 2020. However, South Africa has had little experience in the wind energy industry which is limited to two projects, Klipheuwel (2002) and Darling (2008). Much effort has been dedicated to calculating balance sheet costs, which carries uncertainty due to the high reliance on country specific and site specific variables. An aspect which deserves more attention, and is often ignored, is the public‟s attitudes towards local wind farm developments, which have been known to "make or break" a project during the planning stages. Public backlashes have mostly been concerned with the visual "intrusiveness" of wind farms in the landscape. Detrimental effects on scenery, while seemingly innocuous, are acknowledged as being the single largest barrier to successful wind farm development. Individuals within an area become sentimentally attached to their surroundings, where significant rapid changes in the landscape are viewed as "damage". Economics recognises such declines in scenic resources as market failures, where an externalised cost is passed on to the public and is often not accounted for by private parties responsible for the liability. The primary objective therefore was to measure the magnitude of the visual impact, caused by the Waainek Wind Farm, on the Grahamstown community. Conventional NIMBY¹ (not in my back yard) reasoning, which seeks to explain local wind farm resistance, has attracted criticism with regard to its simplistic approach to wind farm problem identification. Contemporary arguments propose that NIMBY is a poor explanation for the trouble experienced on the local level because it groups problems into one all-encompassing term, leaving much of the discontent unexplained. Instead, the NIMBY explanation is really a broad set of unattended problems, largely resulting from the unsound practices present in the public participation process. Insufficient community involvement and disparities in the negotiation power structures have become the recent focus in wind farm literature. Essentially, these disparities force opposition groups to select factors which may seem more serious to developers, leading to ineffective remedial measures because the core underlying problems are not being remedied. Thus these considerations formed an additional area of investigation. No NIMBY effect was found for the Grahamstown community, as support for both the local and general level was roughly 80%. The public participation process on the other hand revealed that while many found the practices of the developer to be unfair, attitudes towards the wind farm were not adversely affected, especially for the lower income Grahamstown East areas. While the public participation process in this instance did not have any effect on people’s attitudes, careful inspection of the circumstances need to be given. Wind farms are new to South Africa, where the novelty and benefits are the focus of enthusiasm. Job opportunities as well as clean energy are positive drivers for attitudes; however given time, once the anticipation for wind farms dulls, real problems may be revealed. Thus it is crucial to implement good practice procedures during the public participation process, especially when national adoption rates of wind energy are low. Early implementation of an effective public participation process system will ensure that when major problems do arise in future projects, experience and institutional processes would have had ample opportunity to evolve appropriately over a period of time. The double bounded Contingent Valuation Method was used to value the impact of the wind farm on the Waainek scenery through a hypothetical scenario based procedure which presented pictures of the landscape before and after the wind farm had been installed. Based on the perceived impact of the wind farm, respondents were asked their Willingness to Pay to relocate the development, based solely on visual impacts. Learning design Contingent Valuation (Bateman et al., 2008) is a novel technique employed to familiarize respondents with the hypothetical market institution as well as the scenic goods being valued. Average Willingness to Pay was found to be R67 per month, with a final total monthly negative visual impact of R104,000 to R121,000 per month for the entire Grahamstown community. Grahamstown Central (middle-high income) residents were more likely to pay than Grahamstown East (low-middle income) East residents because of socio-economic differences present in each area. A ranking exercise determined that while negative visual impacts are present, the overall benefits derived from the wind farm are potentially much higher. Additionally, positive scenic improvements were found, but were not measured due to time constraints, and would have worked to reduce the net visual impact of the Waainek Wind Farm. ¹Problem where individuals support the general concept of wind power, but when it comes to local implementation, opposition to the development arises within the same group.
- Full Text:
- Date Issued: 2014
The personality of an entrepreneur : a psychobiography of Steve Jobs
- Authors: Ndoro, Tinashe T R
- Date: 2014
- Subjects: Jobs, Steve, 1955-2011 -- Psychology , Personality assessment , Psychology -- Biographical methods , Businesspeople -- Psychology , Psychohistory , Entrepreneurship -- United States , Businesspeople -- United States
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:833 , http://hdl.handle.net/10962/d1013215
- Description: From Integrative Summary: There has been a growing interest in successful entrepreneurs. Research on entrepreneurship has focused on the identification of personality variables that would assist in the prediction of entrepreneurial success. The present study moves away from attempting to predict entrepreneurial success and instead focuses on exploring and describing the personality of a successful entrepreneur. A psychobiographical case study was adopted by the researcher to explore and describe the extent to which Steve Jobs demonstrated the entrepreneurial characteristics identified by Rauch and Frese (2007). A personality trait approach to entrepreneurship was adopted in the study. The study also attempted to explore the socio-cultural and economic context within which Jobs practised his entrepreneurial activities. Jobs was a successful entrepreneur who co-founded Apple and founded NeXT and Pixar, which were all companies that transformed various technological industries. His entrepreneurial orientation allowed him to produce innovative products that transformed society in various sectors which included personal computing, mobile phones, music, retail stores and films (Isaacson, 2011). A qualitative approach was adopted in the study. The data collection and analysis was guided by the three linked sub-processes proposed by Miles and Huberman (2002) which involved data reduction, data display and conclusion drawing and verification. The findings of this study showed that Jobs demonstrated, at varying levels, all the entrepreneurial characteristics identified by Rauch and Frese (2007) which included a need of achievement, risk-taking, innovativeness, autonomy, locus of control and self-efficacy. The researcher however noted that the desire for autonomy, risk-taking, innovativeness and self-efficacy were the most dominant characteristics driving his entrepreneurial orientation. The research thesis adopted the structure of a teaching case which can be used to explore and discuss the personality trait perspective to entrepreneurship in a classroom setting. The findings of the study can be recognised as positively contributing to the growing field of psychobiographical research on exceptional individuals, including entrepreneurs. The study can be considered as a foundation for future studies which will add to the body of knowledge relating to entrepreneurship and personality.
- Full Text:
- Date Issued: 2014
- Authors: Ndoro, Tinashe T R
- Date: 2014
- Subjects: Jobs, Steve, 1955-2011 -- Psychology , Personality assessment , Psychology -- Biographical methods , Businesspeople -- Psychology , Psychohistory , Entrepreneurship -- United States , Businesspeople -- United States
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:833 , http://hdl.handle.net/10962/d1013215
- Description: From Integrative Summary: There has been a growing interest in successful entrepreneurs. Research on entrepreneurship has focused on the identification of personality variables that would assist in the prediction of entrepreneurial success. The present study moves away from attempting to predict entrepreneurial success and instead focuses on exploring and describing the personality of a successful entrepreneur. A psychobiographical case study was adopted by the researcher to explore and describe the extent to which Steve Jobs demonstrated the entrepreneurial characteristics identified by Rauch and Frese (2007). A personality trait approach to entrepreneurship was adopted in the study. The study also attempted to explore the socio-cultural and economic context within which Jobs practised his entrepreneurial activities. Jobs was a successful entrepreneur who co-founded Apple and founded NeXT and Pixar, which were all companies that transformed various technological industries. His entrepreneurial orientation allowed him to produce innovative products that transformed society in various sectors which included personal computing, mobile phones, music, retail stores and films (Isaacson, 2011). A qualitative approach was adopted in the study. The data collection and analysis was guided by the three linked sub-processes proposed by Miles and Huberman (2002) which involved data reduction, data display and conclusion drawing and verification. The findings of this study showed that Jobs demonstrated, at varying levels, all the entrepreneurial characteristics identified by Rauch and Frese (2007) which included a need of achievement, risk-taking, innovativeness, autonomy, locus of control and self-efficacy. The researcher however noted that the desire for autonomy, risk-taking, innovativeness and self-efficacy were the most dominant characteristics driving his entrepreneurial orientation. The research thesis adopted the structure of a teaching case which can be used to explore and discuss the personality trait perspective to entrepreneurship in a classroom setting. The findings of the study can be recognised as positively contributing to the growing field of psychobiographical research on exceptional individuals, including entrepreneurs. The study can be considered as a foundation for future studies which will add to the body of knowledge relating to entrepreneurship and personality.
- Full Text:
- Date Issued: 2014
The potential and reality of the Living Lab model of ICT for Development (ICT4D) in the rural development context : the case of Siyakhula Living Lab, Dwesa, Eastern Cape, South Africa
- Authors: Mosuoe, Teboho Priscilla
- Date: 2014
- Subjects: Siyakhula Living Lab , Information technology -- South Africa -- Dwesa-Cwebe , Communication in economic development -- South Africa -- Dwesa-Cwebe , Rural development projects -- South Africa -- Dwesa-Cwebe , Rural development -- Economic aspects -- South Africa -- Dwesa-Cwebe , Rural development -- South Africa -- Dwesa-Cwebe -- Sociological aspects , Rural development projects -- Evaluation , Social networks -- South Africa -- Dwesa-Cwebe
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3381 , http://hdl.handle.net/10962/d1013289
- Description: This thesis explores the contribution of Information and Communication Technology (ICT) in rural development processes. Within the framework of social capital theory, and in the context of the information society, the study examines how the collaborative and innovative model of ICT for Development (ICT4D) can enhance social networks and information channels in rural communities, thereby enabling the active participation of rural community members in their own development processes. The study examines networks and information channels both within the rural communities under investigation and between these communities and other sectors in the society. The thesis studies the case of the Siyakhula Living Lab (SLL), an ICT4D initiative in the Mbashe Municipality of the Eastern Cape Province of South Africa. During the investigation, four types of networks were identified: local organisations, social institutions, collective community projects and social ties. It was found that the Living Lab has so far influenced the creation of new forms of networks through the common spaces (computer labs) which have been made available by the Living Lab. The study further showed that the use of computers has enabled other community members to partake in the wider community of online/virtual social networks, allowing them to communicate and share information with those outside their own communities. The study also showed that the Living Lab has enabled the networking of these communities with other sectors such as academia. It was, however, found that so far the existence of the Living Lab has not influenced the already existing local networks in these communities. Also, the study showed that the relationship between these rural communities and their government and industry partners as stakeholders in the Living Lab is currently ineffective. Nevertheless, this situation has a potential to change in the future as there are ICT applications which have been developed through collaboration with rural community members, which will assist in enhancing communication between these rural communities and other stakeholders. The study finally revealed that social networks do contribute to the functioning of communities by providing both monetary and social support to community members, even though, in effect, the monetary benefits are somewhat limited by a number of factors. It is revealed that the engagement of ICT could go a long way in improving social and economic activities, governance and service delivery, as well as education in these communities.
- Full Text:
- Date Issued: 2014
- Authors: Mosuoe, Teboho Priscilla
- Date: 2014
- Subjects: Siyakhula Living Lab , Information technology -- South Africa -- Dwesa-Cwebe , Communication in economic development -- South Africa -- Dwesa-Cwebe , Rural development projects -- South Africa -- Dwesa-Cwebe , Rural development -- Economic aspects -- South Africa -- Dwesa-Cwebe , Rural development -- South Africa -- Dwesa-Cwebe -- Sociological aspects , Rural development projects -- Evaluation , Social networks -- South Africa -- Dwesa-Cwebe
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3381 , http://hdl.handle.net/10962/d1013289
- Description: This thesis explores the contribution of Information and Communication Technology (ICT) in rural development processes. Within the framework of social capital theory, and in the context of the information society, the study examines how the collaborative and innovative model of ICT for Development (ICT4D) can enhance social networks and information channels in rural communities, thereby enabling the active participation of rural community members in their own development processes. The study examines networks and information channels both within the rural communities under investigation and between these communities and other sectors in the society. The thesis studies the case of the Siyakhula Living Lab (SLL), an ICT4D initiative in the Mbashe Municipality of the Eastern Cape Province of South Africa. During the investigation, four types of networks were identified: local organisations, social institutions, collective community projects and social ties. It was found that the Living Lab has so far influenced the creation of new forms of networks through the common spaces (computer labs) which have been made available by the Living Lab. The study further showed that the use of computers has enabled other community members to partake in the wider community of online/virtual social networks, allowing them to communicate and share information with those outside their own communities. The study also showed that the Living Lab has enabled the networking of these communities with other sectors such as academia. It was, however, found that so far the existence of the Living Lab has not influenced the already existing local networks in these communities. Also, the study showed that the relationship between these rural communities and their government and industry partners as stakeholders in the Living Lab is currently ineffective. Nevertheless, this situation has a potential to change in the future as there are ICT applications which have been developed through collaboration with rural community members, which will assist in enhancing communication between these rural communities and other stakeholders. The study finally revealed that social networks do contribute to the functioning of communities by providing both monetary and social support to community members, even though, in effect, the monetary benefits are somewhat limited by a number of factors. It is revealed that the engagement of ICT could go a long way in improving social and economic activities, governance and service delivery, as well as education in these communities.
- Full Text:
- Date Issued: 2014
The preparation of antigen for the generation of polyclonal antibodies against the capsid subunit, VP1, and the viral protease, 3Cpro, of Theiler's murine encephalomyelitis virus (TMEV)
- Authors: Moetlhoa, Boitumelo
- Date: 2014
- Subjects: Enteroviruses , Encephalomyelitis , Antigens
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4118 , http://hdl.handle.net/10962/d1013225
- Description: The Picornaviridae is a family of viruses of economic importance that have a major impact on human and animal health. Some of the major genera found in the Picornaviridae family are Enterovirus which includes Poliovirus (PV) and Human Rhinovirus (HRV), Cardiovirus which includes Theiler’s murine encephalomyelitis virus (TMEV) and Saffold virus (SAFV), Aphthovirus of which the Foot and Mouth disease virus (FMDV) is a member and Hepatovirus which includes Hepatitis A virus (HAV). Picornaviruses have a single stranded, positive sense RNA genome which is approximately 7.5-8.4 kb pairs in size. The picornavirus genome is translated into a large polyprotein and is proteolytically cleaved by viral proteases namely 2Apro, 3Cpro and 3CDpro into mature viral structural and non-structural polypeptides encoded by the P1, P2 and P3 domains. Picornaviruses utilise host cell machinery and cellular pathways for entry and uncoating, genome replication and capsid assembly. In our laboratory, we are studying the mechanisms by which TMEV interacts with host cell components and our recent research shows that molecular chaperones are required for a production infection. To follow up on this observation, the overall aim of this study was to prepare antigen for the generation of polyclonal antibodies against the TMEV VP1 and 3Cpro proteins. To this end, the TMEV VP1 and 3Cpro amino acid sequences were analysed to identify hydrophobic, hydrophilic and antigenic regions. Homology modelling was performed in order to predict linear B cell epitopes exposed on the surface of the protein structures. The full length coding sequences of VP1 and 3Cpro were selected for amplification by the PCR and cloning into pQE-80L for expression in a bacterial system. Time course induction studies of recombinant VP1 and 3Cpro showed that the proteins were maximally expressed at 6 hrs and 4 hrs respectively. Recombinant VP1 was solubilised using the detergent, Sarcosyl and purified by Nickel affinity chromatography under native conditions. Because recombinant VP1 co-purified with an unidentified protein, the pET expression system was used. Although no protein of the estimated size was observed by SDS-PAGE analysis in the time course induction study, Western analysis using anti-His6 (2) antibodies detected a signal of ~35 kDa. Solubility studies resulted in the presence of two protein bands in the insoluble fraction resolved between 35 and 40 kDa. Recombinant 3Cpro expressed in a bacterial system was predominantly present in the insoluble fraction. Treatment with Sarcosyl had no effect on the solubility of the recombinant protein and it was therefore purified under denaturing conditions using 8M urea. Following dialysis, 3Cpro was used for immunisation of rabbits. Crude anti-TMEV 3Cpro antibodies were able to detect as little as 107 ng of bacterially expressed antigen at a dilution of 1:100 000 by Western analysis. The presence of contaminating proteins was reduced using pre-cleared anti-TMEV 3Cpro antibodies. The antibodies were unable to detect virally expressed 3Cpro in BHK-21 cell lysate supernatant. In an attempt to determine whether TMEV 3Cpro is present in the insoluble fraction, anti-TMEV 3Cpro antibodies were tested using total protein prepared from infected and mock-infected cell lysates. Once again, no protein band the size of 3Cpro was detected. The antibodies were further tested for detection of 3Cpro in TMEV-infected cells by indirect immunofluorescence and confocal microscopy. A diffuse cytoplasmic and perinuclear distribution, as well as nuclear staining, was observed in infected BHK-21 cells. This staining pattern resembled that observed for the HRV, FMDV and EMCV 3Cpro in similar experiments. Further experiments are required to confirm specificity of these antibodies for virally-expressed 3Cpro by Western analysis and indirect immunofluorescence.
- Full Text:
- Date Issued: 2014
- Authors: Moetlhoa, Boitumelo
- Date: 2014
- Subjects: Enteroviruses , Encephalomyelitis , Antigens
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4118 , http://hdl.handle.net/10962/d1013225
- Description: The Picornaviridae is a family of viruses of economic importance that have a major impact on human and animal health. Some of the major genera found in the Picornaviridae family are Enterovirus which includes Poliovirus (PV) and Human Rhinovirus (HRV), Cardiovirus which includes Theiler’s murine encephalomyelitis virus (TMEV) and Saffold virus (SAFV), Aphthovirus of which the Foot and Mouth disease virus (FMDV) is a member and Hepatovirus which includes Hepatitis A virus (HAV). Picornaviruses have a single stranded, positive sense RNA genome which is approximately 7.5-8.4 kb pairs in size. The picornavirus genome is translated into a large polyprotein and is proteolytically cleaved by viral proteases namely 2Apro, 3Cpro and 3CDpro into mature viral structural and non-structural polypeptides encoded by the P1, P2 and P3 domains. Picornaviruses utilise host cell machinery and cellular pathways for entry and uncoating, genome replication and capsid assembly. In our laboratory, we are studying the mechanisms by which TMEV interacts with host cell components and our recent research shows that molecular chaperones are required for a production infection. To follow up on this observation, the overall aim of this study was to prepare antigen for the generation of polyclonal antibodies against the TMEV VP1 and 3Cpro proteins. To this end, the TMEV VP1 and 3Cpro amino acid sequences were analysed to identify hydrophobic, hydrophilic and antigenic regions. Homology modelling was performed in order to predict linear B cell epitopes exposed on the surface of the protein structures. The full length coding sequences of VP1 and 3Cpro were selected for amplification by the PCR and cloning into pQE-80L for expression in a bacterial system. Time course induction studies of recombinant VP1 and 3Cpro showed that the proteins were maximally expressed at 6 hrs and 4 hrs respectively. Recombinant VP1 was solubilised using the detergent, Sarcosyl and purified by Nickel affinity chromatography under native conditions. Because recombinant VP1 co-purified with an unidentified protein, the pET expression system was used. Although no protein of the estimated size was observed by SDS-PAGE analysis in the time course induction study, Western analysis using anti-His6 (2) antibodies detected a signal of ~35 kDa. Solubility studies resulted in the presence of two protein bands in the insoluble fraction resolved between 35 and 40 kDa. Recombinant 3Cpro expressed in a bacterial system was predominantly present in the insoluble fraction. Treatment with Sarcosyl had no effect on the solubility of the recombinant protein and it was therefore purified under denaturing conditions using 8M urea. Following dialysis, 3Cpro was used for immunisation of rabbits. Crude anti-TMEV 3Cpro antibodies were able to detect as little as 107 ng of bacterially expressed antigen at a dilution of 1:100 000 by Western analysis. The presence of contaminating proteins was reduced using pre-cleared anti-TMEV 3Cpro antibodies. The antibodies were unable to detect virally expressed 3Cpro in BHK-21 cell lysate supernatant. In an attempt to determine whether TMEV 3Cpro is present in the insoluble fraction, anti-TMEV 3Cpro antibodies were tested using total protein prepared from infected and mock-infected cell lysates. Once again, no protein band the size of 3Cpro was detected. The antibodies were further tested for detection of 3Cpro in TMEV-infected cells by indirect immunofluorescence and confocal microscopy. A diffuse cytoplasmic and perinuclear distribution, as well as nuclear staining, was observed in infected BHK-21 cells. This staining pattern resembled that observed for the HRV, FMDV and EMCV 3Cpro in similar experiments. Further experiments are required to confirm specificity of these antibodies for virally-expressed 3Cpro by Western analysis and indirect immunofluorescence.
- Full Text:
- Date Issued: 2014
The presumption of gult created by Section 235(2) of the Tax Administration Act: a constitutional and comparative perspective
- Authors: Faifi, Farai
- Date: 2014
- Subjects: Guilt (Law) -- South Africa , Presumption of innocence -- South Africa , Income tax -- Law and legislation -- South Africa , Human rights -- Taxation -- South Africa , Taxpayer compliance -- Moral and ethical aspects -- South Africa , Taxation -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:907 , http://hdl.handle.net/10962/d1012979
- Description: This research examined the legal nature of the presumption of guilt created by section 235(2) of the South African Tax Admiration Act and considered whether or not its practical application violates the taxpayer’s fundamental right contained in section 35(3) of the Constitution, which gives every accused taxpayer the right to a fair trial, including the right to be presumed innocent. The research also provided clarity on the constitutionality of this presumption because it has been widely criticised for unjustifiably violating the taxpayer's constitutional right to a fair trial. The conclusion reached is that the presumption created by section 235(2) of the Tax Administration Act constitutes an evidentiary burden rather than a reverse onus. It does not create the possibility of conviction, unlike a reverse onus where conviction is possible, despite the existence of a reasonable doubt. Therefore, it does not violate the accused taxpayer’s the right to a fair trial and the right to be presumed innocent and hence it is constitutional. Accordingly, the chances that the accused taxpayer will succeed in challenging the constitutionality of section 235(2) of the Act are slim.
- Full Text:
- Date Issued: 2014
- Authors: Faifi, Farai
- Date: 2014
- Subjects: Guilt (Law) -- South Africa , Presumption of innocence -- South Africa , Income tax -- Law and legislation -- South Africa , Human rights -- Taxation -- South Africa , Taxpayer compliance -- Moral and ethical aspects -- South Africa , Taxation -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:907 , http://hdl.handle.net/10962/d1012979
- Description: This research examined the legal nature of the presumption of guilt created by section 235(2) of the South African Tax Admiration Act and considered whether or not its practical application violates the taxpayer’s fundamental right contained in section 35(3) of the Constitution, which gives every accused taxpayer the right to a fair trial, including the right to be presumed innocent. The research also provided clarity on the constitutionality of this presumption because it has been widely criticised for unjustifiably violating the taxpayer's constitutional right to a fair trial. The conclusion reached is that the presumption created by section 235(2) of the Tax Administration Act constitutes an evidentiary burden rather than a reverse onus. It does not create the possibility of conviction, unlike a reverse onus where conviction is possible, despite the existence of a reasonable doubt. Therefore, it does not violate the accused taxpayer’s the right to a fair trial and the right to be presumed innocent and hence it is constitutional. Accordingly, the chances that the accused taxpayer will succeed in challenging the constitutionality of section 235(2) of the Act are slim.
- Full Text:
- Date Issued: 2014
The principle of complementarity : a critical analysis of Article 17 of the Rome Statute from an African perspective
- Authors: Mohami, Thapelo Adelice
- Date: 2014
- Subjects: Complementarity (International law) , Rome Statute of the International Criminal Court (1998 July 17) , International Criminal Court , Criminal jurisdiction -- Africa , International crimes -- Africa , Crimes against humanity -- Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3720 , http://hdl.handle.net/10962/d1013326
- Description: This thesis attempts to address perennial concerns, mostly raised in some quarters in Africa, pertaining to the development of the complementarity regime established by the Rome Statute of the International Criminal Court. It grapples with a very important question, whether the principle of complementarity, embodied in article 17 of the Rome Statute, was formulated and is being applied by the ICC in a manner that upholds the ideals and theories upon which the regime was founded. The principle of complementarity is designed to mediate the imperatives of State sovereignty and a legitimate international criminal justice system. Essentially, complementarity gives States latitude to try genocide, crimes against humanity, war crimes and aggression nationally, with the ICC only intervening where States are either unable or unwilling to prosecute genuinely. Africa constitutes the biggest regional block of membership to the Rome Statute, however, over the years; support for the ICC on the African continent has waned. It has been argued in some quarters that the ICC is anti-African and that it has interpreted and applied complementarity in a manner that diminishes State sovereignty. The thesis argues that this tension may also be due to textual deficiencies inherent within the Rome Statute, in the provisions that embody this principle. It therefore examines complementarity from a theoretical perspective to provide a comprehensive account of the system contemplated by the drafters of the Rome Statute. In this regard, the thesis argues for expansion of States’ ability at the national level to deal with international crimes without compromising international criminal justice processes or threatening State sovereignty. This is suggested as a way of relieving the tension that has characterised the relationship between African States and the ICC. The thesis further sketches out some of the complexities inherent in the modalities through which the Court may exercise its complementary jurisdiction, particularly within the African continent, given that legal systems in most African countries are particularly weak. It thus dissects the provisions that outline the principle of complementarity in tandem with the Court’s interpretation and application of complementarity in practice. Furthermore, through an exploratory survey of the referral of the Situation in Uganda, and the ICC Prosecutor’s proprio motu investigation of the Situation in Kenya, the thesis illustrates how a positive approach to complementarity can help establish a healthy cooperative synergy between the ICC and States, thereby promoting a functional expeditious criminal justice system. This will go a long way towards assuaging State’s fears that the ICC merely pays lip service to complementarity and arbitrarily supersedes national jurisdiction.
- Full Text:
- Date Issued: 2014
- Authors: Mohami, Thapelo Adelice
- Date: 2014
- Subjects: Complementarity (International law) , Rome Statute of the International Criminal Court (1998 July 17) , International Criminal Court , Criminal jurisdiction -- Africa , International crimes -- Africa , Crimes against humanity -- Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3720 , http://hdl.handle.net/10962/d1013326
- Description: This thesis attempts to address perennial concerns, mostly raised in some quarters in Africa, pertaining to the development of the complementarity regime established by the Rome Statute of the International Criminal Court. It grapples with a very important question, whether the principle of complementarity, embodied in article 17 of the Rome Statute, was formulated and is being applied by the ICC in a manner that upholds the ideals and theories upon which the regime was founded. The principle of complementarity is designed to mediate the imperatives of State sovereignty and a legitimate international criminal justice system. Essentially, complementarity gives States latitude to try genocide, crimes against humanity, war crimes and aggression nationally, with the ICC only intervening where States are either unable or unwilling to prosecute genuinely. Africa constitutes the biggest regional block of membership to the Rome Statute, however, over the years; support for the ICC on the African continent has waned. It has been argued in some quarters that the ICC is anti-African and that it has interpreted and applied complementarity in a manner that diminishes State sovereignty. The thesis argues that this tension may also be due to textual deficiencies inherent within the Rome Statute, in the provisions that embody this principle. It therefore examines complementarity from a theoretical perspective to provide a comprehensive account of the system contemplated by the drafters of the Rome Statute. In this regard, the thesis argues for expansion of States’ ability at the national level to deal with international crimes without compromising international criminal justice processes or threatening State sovereignty. This is suggested as a way of relieving the tension that has characterised the relationship between African States and the ICC. The thesis further sketches out some of the complexities inherent in the modalities through which the Court may exercise its complementary jurisdiction, particularly within the African continent, given that legal systems in most African countries are particularly weak. It thus dissects the provisions that outline the principle of complementarity in tandem with the Court’s interpretation and application of complementarity in practice. Furthermore, through an exploratory survey of the referral of the Situation in Uganda, and the ICC Prosecutor’s proprio motu investigation of the Situation in Kenya, the thesis illustrates how a positive approach to complementarity can help establish a healthy cooperative synergy between the ICC and States, thereby promoting a functional expeditious criminal justice system. This will go a long way towards assuaging State’s fears that the ICC merely pays lip service to complementarity and arbitrarily supersedes national jurisdiction.
- Full Text:
- Date Issued: 2014
The relationship between service quality, customer satisfaction and customer loyalty in the retail supermarket industry
- Authors: Ndhlovu, Thinkwell
- Date: 2014
- Subjects: Consumer satisfaction , Customer loyalty , Customer services -- Rating of , Customer services -- Quality control , Relationship marketing , Supermarkets -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1202 , http://hdl.handle.net/10962/d1013221
- Description: The increasingly competitive business environment has influenced contemporary organisations to build mutual beneficial relationships with their customers indicating a paradigm shift from transactional marketing. In order to compete in this intense competitive environment, organisations are creating competitive advantage over their rivals through service quality that will influence customer satisfaction which subsequently leads to customer loyalty. Service quality has been found to be the key strategy of success and survival for most organisations like retail supermarkets who want to win the loyalty of their customers because of its positive effect on customer satisfaction. The purpose of this research was to determine the relationship between service quality, customer satisfaction and customer loyalty in the retail supermarket industry. An empirical study was conducted in Grahamstown between two main supermarkets through a survey that determined customers’ perceptions on service quality, customer satisfaction and customer loyalty respectively. The empirical findings of this research study revealed that moderate to strong positive linear relationships exists between the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) and customer satisfaction at the 5% level of significance. Furthermore, this study showed that dimensions of service quality (namely physical aspects, reliability, personal interaction and problem solving) have weak negative linear relationships with price sensitivity dimension of customer loyalty. The study further showed that the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) have weak to moderate positive linear relationships with the purchase intentions dimension of customer loyalty. In addition, all the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) showed moderate positive linear relationships with word of mouth communication dimension of customer loyalty. A weak negative linear relationship between price sensitivity dimension of customer loyalty and customer satisfaction was revealed in this study. Purchase intentions dimension of customer loyalty was also found to have a moderate positive linear relationship with customer satisfaction. In addition, word of mouth communication dimension of customer loyalty showed a strong positive linear relationship with customer satisfaction. There is sufficient evidence that the customers of the two supermarkets in this study have different perceptions on problem solving dimension of service quality. This study further provides sufficient evidence of the significant difference between gender on the levels of customer satisfaction. In addition, this study showed that customers of various levels of education and occupations differ in price sensitivity dimension of customer loyalty. The average scores for word of mouth communication, purchase intentions and price sensitivity dimensions of customer loyalty were found to be significantly different between the two supermarkets investigated in this study. Therefore, for supermarkets to compete effectively in the intense retail supermarket industry in South Africa they have to manage their service quality dimensions so as to influence customer satisfaction and customer loyalty respectively.
- Full Text:
- Date Issued: 2014
- Authors: Ndhlovu, Thinkwell
- Date: 2014
- Subjects: Consumer satisfaction , Customer loyalty , Customer services -- Rating of , Customer services -- Quality control , Relationship marketing , Supermarkets -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1202 , http://hdl.handle.net/10962/d1013221
- Description: The increasingly competitive business environment has influenced contemporary organisations to build mutual beneficial relationships with their customers indicating a paradigm shift from transactional marketing. In order to compete in this intense competitive environment, organisations are creating competitive advantage over their rivals through service quality that will influence customer satisfaction which subsequently leads to customer loyalty. Service quality has been found to be the key strategy of success and survival for most organisations like retail supermarkets who want to win the loyalty of their customers because of its positive effect on customer satisfaction. The purpose of this research was to determine the relationship between service quality, customer satisfaction and customer loyalty in the retail supermarket industry. An empirical study was conducted in Grahamstown between two main supermarkets through a survey that determined customers’ perceptions on service quality, customer satisfaction and customer loyalty respectively. The empirical findings of this research study revealed that moderate to strong positive linear relationships exists between the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) and customer satisfaction at the 5% level of significance. Furthermore, this study showed that dimensions of service quality (namely physical aspects, reliability, personal interaction and problem solving) have weak negative linear relationships with price sensitivity dimension of customer loyalty. The study further showed that the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) have weak to moderate positive linear relationships with the purchase intentions dimension of customer loyalty. In addition, all the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) showed moderate positive linear relationships with word of mouth communication dimension of customer loyalty. A weak negative linear relationship between price sensitivity dimension of customer loyalty and customer satisfaction was revealed in this study. Purchase intentions dimension of customer loyalty was also found to have a moderate positive linear relationship with customer satisfaction. In addition, word of mouth communication dimension of customer loyalty showed a strong positive linear relationship with customer satisfaction. There is sufficient evidence that the customers of the two supermarkets in this study have different perceptions on problem solving dimension of service quality. This study further provides sufficient evidence of the significant difference between gender on the levels of customer satisfaction. In addition, this study showed that customers of various levels of education and occupations differ in price sensitivity dimension of customer loyalty. The average scores for word of mouth communication, purchase intentions and price sensitivity dimensions of customer loyalty were found to be significantly different between the two supermarkets investigated in this study. Therefore, for supermarkets to compete effectively in the intense retail supermarket industry in South Africa they have to manage their service quality dimensions so as to influence customer satisfaction and customer loyalty respectively.
- Full Text:
- Date Issued: 2014
The rising popularity of Pidgin English radio stations in Nigeria: an audience study of Wazobia FM, Lagos
- Durodola, Olufunke Treasure Anike
- Authors: Durodola, Olufunke Treasure Anike
- Date: 2014
- Subjects: Wazobia FM (Nigeria) , Radio audiences -- Nigeria -- Lagos , Pidgin English -- Nigeria -- Lagos , Radio stations -- Nigeria -- Lagos , Mass media and culture -- Nigeria -- Lagos , Language and languages -- Variation , Popular culture -- Nigeria , Postcolonialism -- Nigeria
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3550 , http://hdl.handle.net/10962/d1020886
- Description: This research is located within media studies and draws on the Cultural Studies approach. It is an audience study, which uses the mixed methods of focus group discussions and an online survey to examine the importance of the use of Nigerian Pidgin as a broadcast language in investigating the rising popularity of Pidgin English radio in a multi-ethnic and multi-lingual Nigeria. The study focuses on Wazobia FM, a radio station in Lagos, and the first pidgin station in Nigeria. It seeks to determine whether the station’s audience engaged with the station’s programming based on its prioritisation of NigP and the linguistic identity it offers them. The study foregrounds the marginalised status of NigP within the politics of language in Nigeria. It traces the language’s evolution through popular and oppositional expressions in broadcasting and in music. It also seeks to establish the place of Pidgin English within the role that language plays in the formation of the Nigerian identity. This study thus adopts the ‘emic’ perspective, which underpins qualitative methodology, and views social life in terms of processes as opposed to static terms. The theoretical framework of this research revolves around culture, language and identity. Pertinent concepts in post-colonial studies, together with conceptual frameworks in Cultural Studies, such as popular culture, representation, hegemony and counter-culture have been used to make sense of the popularity of NigP radio stations.
- Full Text:
- Date Issued: 2014
- Authors: Durodola, Olufunke Treasure Anike
- Date: 2014
- Subjects: Wazobia FM (Nigeria) , Radio audiences -- Nigeria -- Lagos , Pidgin English -- Nigeria -- Lagos , Radio stations -- Nigeria -- Lagos , Mass media and culture -- Nigeria -- Lagos , Language and languages -- Variation , Popular culture -- Nigeria , Postcolonialism -- Nigeria
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3550 , http://hdl.handle.net/10962/d1020886
- Description: This research is located within media studies and draws on the Cultural Studies approach. It is an audience study, which uses the mixed methods of focus group discussions and an online survey to examine the importance of the use of Nigerian Pidgin as a broadcast language in investigating the rising popularity of Pidgin English radio in a multi-ethnic and multi-lingual Nigeria. The study focuses on Wazobia FM, a radio station in Lagos, and the first pidgin station in Nigeria. It seeks to determine whether the station’s audience engaged with the station’s programming based on its prioritisation of NigP and the linguistic identity it offers them. The study foregrounds the marginalised status of NigP within the politics of language in Nigeria. It traces the language’s evolution through popular and oppositional expressions in broadcasting and in music. It also seeks to establish the place of Pidgin English within the role that language plays in the formation of the Nigerian identity. This study thus adopts the ‘emic’ perspective, which underpins qualitative methodology, and views social life in terms of processes as opposed to static terms. The theoretical framework of this research revolves around culture, language and identity. Pertinent concepts in post-colonial studies, together with conceptual frameworks in Cultural Studies, such as popular culture, representation, hegemony and counter-culture have been used to make sense of the popularity of NigP radio stations.
- Full Text:
- Date Issued: 2014
The role of computational thinking in introductory computer science
- Authors: Gouws, Lindsey Ann
- Date: 2014
- Subjects: Computer science , Computational complexity , Problem solving -- Study and teaching
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4690 , http://hdl.handle.net/10962/d1011152 , Computer science , Computational complexity , Problem solving -- Study and teaching
- Description: Computational thinking (CT) is gaining recognition as an important skill for students, both in computer science and other disciplines. Although there has been much focus on this field in recent years, it is rarely taught as a formal course, and there is little consensus on what exactly CT entails and how to teach and evaluate it. This research addresses the lack of resources for integrating CT into the introductory computer science curriculum. The question that we aim to answer is whether CT can be evaluated in a meaningful way. A CT framework that outlines the skills and techniques comprising CT and describes the nature of student engagement was developed; this is used as the basis for this research. An assessment (CT test) was then created to gauge the ability of incoming students, and a CT-specfic computer game was developed based on the analysis of an existing game. A set of problem solving strategies and practice activities were then recommended based on criteria defined in the framework. The results revealed that the CT abilities of first year university students are relatively poor, but that the students' scores for the CT test could be used as a predictor for their future success in computer science courses. The framework developed for this research proved successful when applied to the test, computer game evaluation, and classification of strategies and activities. Through this research, we established that CT is a skill that first year computer science students are lacking, and that using CT exercises alongside traditional programming instruction can improve students' learning experiences.
- Full Text:
- Date Issued: 2014
- Authors: Gouws, Lindsey Ann
- Date: 2014
- Subjects: Computer science , Computational complexity , Problem solving -- Study and teaching
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4690 , http://hdl.handle.net/10962/d1011152 , Computer science , Computational complexity , Problem solving -- Study and teaching
- Description: Computational thinking (CT) is gaining recognition as an important skill for students, both in computer science and other disciplines. Although there has been much focus on this field in recent years, it is rarely taught as a formal course, and there is little consensus on what exactly CT entails and how to teach and evaluate it. This research addresses the lack of resources for integrating CT into the introductory computer science curriculum. The question that we aim to answer is whether CT can be evaluated in a meaningful way. A CT framework that outlines the skills and techniques comprising CT and describes the nature of student engagement was developed; this is used as the basis for this research. An assessment (CT test) was then created to gauge the ability of incoming students, and a CT-specfic computer game was developed based on the analysis of an existing game. A set of problem solving strategies and practice activities were then recommended based on criteria defined in the framework. The results revealed that the CT abilities of first year university students are relatively poor, but that the students' scores for the CT test could be used as a predictor for their future success in computer science courses. The framework developed for this research proved successful when applied to the test, computer game evaluation, and classification of strategies and activities. Through this research, we established that CT is a skill that first year computer science students are lacking, and that using CT exercises alongside traditional programming instruction can improve students' learning experiences.
- Full Text:
- Date Issued: 2014
The water and nutrient potential of brewery effluent for hydroponic tomato production
- Authors: Power, Sean Duncan
- Date: 2014
- Subjects: Hydroponics , Tomatoes -- Breeding , Brewery waste , Water -- Purification , Algae culture , Algae -- Biotechnology , Nitric acid , Phosphoric acid
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5358 , http://hdl.handle.net/10962/d1011604 , Hydroponics , Tomatoes -- Breeding , Brewery waste , Water -- Purification , Algae culture , Algae -- Biotechnology , Nitric acid , Phosphoric acid
- Description: Brewery effluent that had undergone treatment in an anaerobic digester (AD) was used as an alternative water and nutrient source for hydroponic crop production. Brewery effluent was demonstrated to contain sufficient nutrients to support the growth, flowering and fruiting of Lycopersicum escolentum "Moneymaker" tomato crops. The adjustment of the effluent pH with phosphoric acid to between pH 6.0 and 6.5 increased the development of the crops by around 100% compared to crops grown in unaltered effluent. The pH adjusted effluent-grown plants grew to a mean height of 831.4 ± 21.1 mm and a dry biomass weight of 42.34 ± 2.76 g compared to the unaltered pH effluent plants which grew to a height of 410.6 ± 20.5 mm and a weight of 7.65 ± 0.68 g after 49 days. Effluent treatment in high-rate algal ponds (HRAP) was determined to have no positive effect on the nutritional potential of the effluent for Moneymaker production. The effluent-grown plants did not perform as well as plants grown in inorganic-fertilizer and municipal water. Plants grown in effluent grew taller but did not produce significantly more fruit when phosphoric acid (height: 1573.3 ± 50.4 mm, 19.4 ± 1.4 fruit per plant) was compared to nitric acid (height: 1254.1 ± 25.4 mm, 15.6 ± 1.5 fruit per plant) as the pH adjustment over 72 days. Direct and secondary plant stresses from effluent alkalinity, ammonium nutrition, nitrogen limitation, sodium concentrations and heat stress among other factors were probably confounding variables in these trials and require further investigation. Considering the raw effluent composition and manipulating the AD operation is a potential opportunity to improve overall AD performance, reduce chemical inputs in the effluent treatment process, reduce the final effluent alkalinity, and increase available nitrogen content in the final effluent. The anaerobic digester discharging >1000 m³ of nutrient enriched effluent every day is a resource with considerable potential. The benefits of developing this resource can contribute to cost-reduction at the brewery, more efficient water, nutrient and energy management at the brewery, and offer opportunities for job creation and potentially benefit local food security.
- Full Text:
- Date Issued: 2014
- Authors: Power, Sean Duncan
- Date: 2014
- Subjects: Hydroponics , Tomatoes -- Breeding , Brewery waste , Water -- Purification , Algae culture , Algae -- Biotechnology , Nitric acid , Phosphoric acid
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5358 , http://hdl.handle.net/10962/d1011604 , Hydroponics , Tomatoes -- Breeding , Brewery waste , Water -- Purification , Algae culture , Algae -- Biotechnology , Nitric acid , Phosphoric acid
- Description: Brewery effluent that had undergone treatment in an anaerobic digester (AD) was used as an alternative water and nutrient source for hydroponic crop production. Brewery effluent was demonstrated to contain sufficient nutrients to support the growth, flowering and fruiting of Lycopersicum escolentum "Moneymaker" tomato crops. The adjustment of the effluent pH with phosphoric acid to between pH 6.0 and 6.5 increased the development of the crops by around 100% compared to crops grown in unaltered effluent. The pH adjusted effluent-grown plants grew to a mean height of 831.4 ± 21.1 mm and a dry biomass weight of 42.34 ± 2.76 g compared to the unaltered pH effluent plants which grew to a height of 410.6 ± 20.5 mm and a weight of 7.65 ± 0.68 g after 49 days. Effluent treatment in high-rate algal ponds (HRAP) was determined to have no positive effect on the nutritional potential of the effluent for Moneymaker production. The effluent-grown plants did not perform as well as plants grown in inorganic-fertilizer and municipal water. Plants grown in effluent grew taller but did not produce significantly more fruit when phosphoric acid (height: 1573.3 ± 50.4 mm, 19.4 ± 1.4 fruit per plant) was compared to nitric acid (height: 1254.1 ± 25.4 mm, 15.6 ± 1.5 fruit per plant) as the pH adjustment over 72 days. Direct and secondary plant stresses from effluent alkalinity, ammonium nutrition, nitrogen limitation, sodium concentrations and heat stress among other factors were probably confounding variables in these trials and require further investigation. Considering the raw effluent composition and manipulating the AD operation is a potential opportunity to improve overall AD performance, reduce chemical inputs in the effluent treatment process, reduce the final effluent alkalinity, and increase available nitrogen content in the final effluent. The anaerobic digester discharging >1000 m³ of nutrient enriched effluent every day is a resource with considerable potential. The benefits of developing this resource can contribute to cost-reduction at the brewery, more efficient water, nutrient and energy management at the brewery, and offer opportunities for job creation and potentially benefit local food security.
- Full Text:
- Date Issued: 2014
Thermoluminescence characteristics of synthetic quartz
- Authors: Niyonzima, Pontien
- Date: 2014
- Subjects: Thermoluminescence , Quartz , Emission spectroscopy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5538 , http://hdl.handle.net/10962/d1013190
- Description: Quartz is one of the most abundant natural minerals in the crust of the earth. Due to its dosimetric luminescence properties, it is employed in retrospective dosimetry, archaeological and geological dating. The intensity and the structure of the TL glow curves of quartz are strongly dependent upon the origin, impurity content, formation condition and pre-irradiation heat treatment. The aim of this project is to study the mechanisms of thermoluminescence (TL), Phototranssferred thermoluminescence (PTTL) and radioluminescence (RL) in synthetic quartz and to discuss the results in terms of physical characteristics of point defects involved. Thermoluminescence measurements were made on a sample of synthetic quartz in its as-received state (unannealed) synthetic quartz annealed at 500˚C for 10 minutes. The unannealed sample shows six TL glow peaks located at 94, 116, 176, 212, 280 and 348˚C at a heating rate of 5˚Cs⁻¹. The annealed sample shows seven TL peaks at 115, 148, 214, 246, 300, 348 and 412˚C at a heating rate of 5˚Cs⁻¹. The intensity of peak I, at 94 and 115˚C for the unannealed and annealed samples respectively, increases with irradiation. Peak I has an activation energy of approximately 0.90 eV and a frequency factor of the order of 10¹¹ s⁻¹. The order of kinetics is between 0.9 and 1.2. The unannealed synthetic quartz shows phototransferred thermoluminescence (PTTL) at the position of peak I after removal of the first three peaks followed by illumination. The PTTL intensities show peak shaped behaviour when plotted against illumination time. The PTTL showed a quadratic increase with dose. The material exhibits fading of PTTL intensity with delay time. Radioluminescence was measured on synthetic quartz unannealed and annealed annealed at 500, 600, 700, 800, 900 and 1000˚C for 10 to 60 min. The emission spectra of synthetic quartz show seven emission bands. The effect of irradiation on the RL spectra is to increase the intensity of all emission bands for samples annealed at temperatures less than or equal to 700˚C. The effect of annealing time is to increase the RL amplitude for the samples annealed at temperatures greater than 700˚C. The annealing temperature increases the RL amplitude of all emission bands of the spectrum for all samples.
- Full Text:
- Date Issued: 2014
- Authors: Niyonzima, Pontien
- Date: 2014
- Subjects: Thermoluminescence , Quartz , Emission spectroscopy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5538 , http://hdl.handle.net/10962/d1013190
- Description: Quartz is one of the most abundant natural minerals in the crust of the earth. Due to its dosimetric luminescence properties, it is employed in retrospective dosimetry, archaeological and geological dating. The intensity and the structure of the TL glow curves of quartz are strongly dependent upon the origin, impurity content, formation condition and pre-irradiation heat treatment. The aim of this project is to study the mechanisms of thermoluminescence (TL), Phototranssferred thermoluminescence (PTTL) and radioluminescence (RL) in synthetic quartz and to discuss the results in terms of physical characteristics of point defects involved. Thermoluminescence measurements were made on a sample of synthetic quartz in its as-received state (unannealed) synthetic quartz annealed at 500˚C for 10 minutes. The unannealed sample shows six TL glow peaks located at 94, 116, 176, 212, 280 and 348˚C at a heating rate of 5˚Cs⁻¹. The annealed sample shows seven TL peaks at 115, 148, 214, 246, 300, 348 and 412˚C at a heating rate of 5˚Cs⁻¹. The intensity of peak I, at 94 and 115˚C for the unannealed and annealed samples respectively, increases with irradiation. Peak I has an activation energy of approximately 0.90 eV and a frequency factor of the order of 10¹¹ s⁻¹. The order of kinetics is between 0.9 and 1.2. The unannealed synthetic quartz shows phototransferred thermoluminescence (PTTL) at the position of peak I after removal of the first three peaks followed by illumination. The PTTL intensities show peak shaped behaviour when plotted against illumination time. The PTTL showed a quadratic increase with dose. The material exhibits fading of PTTL intensity with delay time. Radioluminescence was measured on synthetic quartz unannealed and annealed annealed at 500, 600, 700, 800, 900 and 1000˚C for 10 to 60 min. The emission spectra of synthetic quartz show seven emission bands. The effect of irradiation on the RL spectra is to increase the intensity of all emission bands for samples annealed at temperatures less than or equal to 700˚C. The effect of annealing time is to increase the RL amplitude for the samples annealed at temperatures greater than 700˚C. The annealing temperature increases the RL amplitude of all emission bands of the spectrum for all samples.
- Full Text:
- Date Issued: 2014
Thermoluminescence of natural quartz
- Authors: Lontsi Sob, Aaron Joel
- Date: 2014
- Subjects: Thermoluminescence , Quartz , Thermoluminescence dosimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5543 , http://hdl.handle.net/10962/d1013358
- Description: The kinetic and dosimetric features of the main thermoluminescence peak of quartz have been investigated in unannealed as well in quartz annealed at 500˚C for 10 minutes. The main peak is found at 92 and 86˚C respectively for aliquots of unannealed and annealed samples irradiated to 10 Gy and heated at 5.0˚C/s. For each sample, the intensity of the main peak is enhanced with repetitive measurement whereas its maximum temperature is unaffected. The peak position of the main peak in each sample is independent of the irradiation dose and this, together with its fading characteristics are consistent with first-order kinetics. For low doses, typically between 2 and 10 Gy, the dose response of the main peak in each sample is linear. In the intermediate dose range from 10 to 60 Gy, the growth of the main peak in each sample is sub-linear and for greater doses, in the range from 60 Gy to 151 Gy, it is linear again. The half-life of the main peak of the unannealed sample is about 1.3 h whereas that of the annealed sample is about 1.2 h. The main peak in each sample can be approximated to a first-order glow peak. As the heating rate increases, the intensity of the main peak in each sample decreases. This is evidence of thermal quenching. The main peak in each sample is the only peak regenerated by phototransfer. The resulting phototransferred peak occurs at the same temperature as the original peak and has similar kinetic and dosimetric features. For a preheat temperature of 120˚C, the intensity of the phototransferred peak in each sample increases with illumination time up to a maximum and decreases afterwards. At longer illumination times (such as 30 min up to 1 h), no further decrease in the intensity of the phototransferred peak is observed. The traps associated with the 325˚C peak are the main source of the electrons responsible for the regenerated peak. Radioluminescence emission spectra were also measured for quartz annealed at various temperatures. Emission bands in quartz are affected by annealing and irradiation. A strong enhancement of the 3.4 eV (~366 nm) emission band is observed in quartz annealed at 500˚C. A new emission band which grows with annealing up to 1000˚C is observed at 3.7 eV (~330 nm) for quartz annealed at 600˚C. An attempt has been made to correlate the changes in radioluminescence emission spectra due to annealing with the influence of annealing on luminescence lifetimes in quartz.
- Full Text:
- Date Issued: 2014
- Authors: Lontsi Sob, Aaron Joel
- Date: 2014
- Subjects: Thermoluminescence , Quartz , Thermoluminescence dosimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5543 , http://hdl.handle.net/10962/d1013358
- Description: The kinetic and dosimetric features of the main thermoluminescence peak of quartz have been investigated in unannealed as well in quartz annealed at 500˚C for 10 minutes. The main peak is found at 92 and 86˚C respectively for aliquots of unannealed and annealed samples irradiated to 10 Gy and heated at 5.0˚C/s. For each sample, the intensity of the main peak is enhanced with repetitive measurement whereas its maximum temperature is unaffected. The peak position of the main peak in each sample is independent of the irradiation dose and this, together with its fading characteristics are consistent with first-order kinetics. For low doses, typically between 2 and 10 Gy, the dose response of the main peak in each sample is linear. In the intermediate dose range from 10 to 60 Gy, the growth of the main peak in each sample is sub-linear and for greater doses, in the range from 60 Gy to 151 Gy, it is linear again. The half-life of the main peak of the unannealed sample is about 1.3 h whereas that of the annealed sample is about 1.2 h. The main peak in each sample can be approximated to a first-order glow peak. As the heating rate increases, the intensity of the main peak in each sample decreases. This is evidence of thermal quenching. The main peak in each sample is the only peak regenerated by phototransfer. The resulting phototransferred peak occurs at the same temperature as the original peak and has similar kinetic and dosimetric features. For a preheat temperature of 120˚C, the intensity of the phototransferred peak in each sample increases with illumination time up to a maximum and decreases afterwards. At longer illumination times (such as 30 min up to 1 h), no further decrease in the intensity of the phototransferred peak is observed. The traps associated with the 325˚C peak are the main source of the electrons responsible for the regenerated peak. Radioluminescence emission spectra were also measured for quartz annealed at various temperatures. Emission bands in quartz are affected by annealing and irradiation. A strong enhancement of the 3.4 eV (~366 nm) emission band is observed in quartz annealed at 500˚C. A new emission band which grows with annealing up to 1000˚C is observed at 3.7 eV (~330 nm) for quartz annealed at 600˚C. An attempt has been made to correlate the changes in radioluminescence emission spectra due to annealing with the influence of annealing on luminescence lifetimes in quartz.
- Full Text:
- Date Issued: 2014
Thermoluminescence of secondary glow peaks in carbon-doped aluminium oxide
- Authors: Seneza, Cleophace
- Date: 2014
- Subjects: Thermoluminescence , Aluminum oxide , Thermoluminescence dosimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5537 , http://hdl.handle.net/10962/d1013053
- Description: Carbon-doped aluminium oxide, α-Al₂O₃ : C, is a highly sensitive luminescence dosimeter. The high sensitivity of α-Al₂O₃ : C has been attributed to large concentrations of oxygen vacancies, F and F⁺ centres, induced in the material during its preparation. The material is prepared in a highly reducing atmosphere in the presence of carbon. In the luminescence process, electrons are trapped in F-centre defects as a result of irradiation of the material. Thermal or optical release of trapped electrons leads to emission of light, thermoluminescence (TL) or optically stimulated light (OSL) respectively. The thermoluminescence technique is used to study point defects involved in luminescence of α-Al₂O₃ : C. A glow curve of α-Al₂O₃ : C, generally, shows three peaks; the main dosimetric peak of high intensity (peak II) and two other peaks of lower intensity called secondary glow peaks (peaks I and III). The overall aim of our work was to study the TL mechanisms responsible for secondary glow peaks in α-Al₂O₃ : C. The dynamics of charge movement between centres during the TL process was studied. The phototransferred thermoluminescence (PTTL) from secondary glow peaks was also studied. The kinetic analysis of TL from secondary peaks has shown that the activation energy of peak I is 0.7 eV and that of peak III, 1.2 eV. The frequency factor, the frequency at which an electron attempts to escape a trap, was found near the range of the Debye vibration frequency. Values of the activation energy are consistent within a variety of methods used. The two peaks follow first order kinetics as confirmed by the TM-Tstop method. A linear dependence of TL from peak I on dose is observed at various doses from 0.5 to 2.5 Gy. The peak position for peak I was also independent on dose, further confirmation that peak I is of first order kinetics. Peak I suffers from thermal fading with storage with a half-life of about 120 s. The dependence of TL intensity for peak I increased as a function of heating rate from 0.2 to 6ºCs⁻¹. In contrast to the TL intensity for peak I, the intensity of TL for peak III decreases with an increase of heating rate from 0.2 to 6ºCs⁻¹. This is evidence of thermal quenching for peak III. Parameters W = 1.48 ± 0:10 eV and C = 4 x 10¹³ of thermal quenching were calculated from peak III intensities at different heating rates. Thermal cleaning of peak III and the glow curve deconvolution methods confirmed that the main peak is actually overlapped by a small peak (labeled peak IIA). The kinetic analysis of peak IIA showed that it is of first order kinetics and that its activation energy is 1:0 eV. In addition, the peak IIA is affected by thermal quenching. Another secondary peak appears at 422ºC (peak IV). However, the kinetic analysis of TL from peak IV was not studied because its intensity is not well defined. A heating rate of 0.4ºCs⁻¹ was used after a dose of 3 Gy in kinetic analysis of peaks IIA and III. The study of the PTTL showed that peaks I and II were regenerated under PTTL but peak III was not. Various effects of the PTTL for peaks I and II for different preheating temperatures in different samples were observed. The effect of annealing at 900ºC for 15 minutes between measurements following each illumination time was studied. The effect of dose on secondary peaks was also studied in this work. The kinetic analysis of the PTTL intensity for peak I showed that its activation energy is 0.7 eV, consistent with the activation energy of the normal TL for peak I. The PTTL intensity from peak I fades rapidly with storage compared with the thermal fading from peak I of the normal TL. The PTTL intensity for peak I decreases as a function of heating rate. This decrease was attributed to thermal quenching. Thermal quenching was not observed in the case of the normal TL intensity. The cause of this contrast requires further study.
- Full Text:
- Date Issued: 2014
- Authors: Seneza, Cleophace
- Date: 2014
- Subjects: Thermoluminescence , Aluminum oxide , Thermoluminescence dosimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5537 , http://hdl.handle.net/10962/d1013053
- Description: Carbon-doped aluminium oxide, α-Al₂O₃ : C, is a highly sensitive luminescence dosimeter. The high sensitivity of α-Al₂O₃ : C has been attributed to large concentrations of oxygen vacancies, F and F⁺ centres, induced in the material during its preparation. The material is prepared in a highly reducing atmosphere in the presence of carbon. In the luminescence process, electrons are trapped in F-centre defects as a result of irradiation of the material. Thermal or optical release of trapped electrons leads to emission of light, thermoluminescence (TL) or optically stimulated light (OSL) respectively. The thermoluminescence technique is used to study point defects involved in luminescence of α-Al₂O₃ : C. A glow curve of α-Al₂O₃ : C, generally, shows three peaks; the main dosimetric peak of high intensity (peak II) and two other peaks of lower intensity called secondary glow peaks (peaks I and III). The overall aim of our work was to study the TL mechanisms responsible for secondary glow peaks in α-Al₂O₃ : C. The dynamics of charge movement between centres during the TL process was studied. The phototransferred thermoluminescence (PTTL) from secondary glow peaks was also studied. The kinetic analysis of TL from secondary peaks has shown that the activation energy of peak I is 0.7 eV and that of peak III, 1.2 eV. The frequency factor, the frequency at which an electron attempts to escape a trap, was found near the range of the Debye vibration frequency. Values of the activation energy are consistent within a variety of methods used. The two peaks follow first order kinetics as confirmed by the TM-Tstop method. A linear dependence of TL from peak I on dose is observed at various doses from 0.5 to 2.5 Gy. The peak position for peak I was also independent on dose, further confirmation that peak I is of first order kinetics. Peak I suffers from thermal fading with storage with a half-life of about 120 s. The dependence of TL intensity for peak I increased as a function of heating rate from 0.2 to 6ºCs⁻¹. In contrast to the TL intensity for peak I, the intensity of TL for peak III decreases with an increase of heating rate from 0.2 to 6ºCs⁻¹. This is evidence of thermal quenching for peak III. Parameters W = 1.48 ± 0:10 eV and C = 4 x 10¹³ of thermal quenching were calculated from peak III intensities at different heating rates. Thermal cleaning of peak III and the glow curve deconvolution methods confirmed that the main peak is actually overlapped by a small peak (labeled peak IIA). The kinetic analysis of peak IIA showed that it is of first order kinetics and that its activation energy is 1:0 eV. In addition, the peak IIA is affected by thermal quenching. Another secondary peak appears at 422ºC (peak IV). However, the kinetic analysis of TL from peak IV was not studied because its intensity is not well defined. A heating rate of 0.4ºCs⁻¹ was used after a dose of 3 Gy in kinetic analysis of peaks IIA and III. The study of the PTTL showed that peaks I and II were regenerated under PTTL but peak III was not. Various effects of the PTTL for peaks I and II for different preheating temperatures in different samples were observed. The effect of annealing at 900ºC for 15 minutes between measurements following each illumination time was studied. The effect of dose on secondary peaks was also studied in this work. The kinetic analysis of the PTTL intensity for peak I showed that its activation energy is 0.7 eV, consistent with the activation energy of the normal TL for peak I. The PTTL intensity from peak I fades rapidly with storage compared with the thermal fading from peak I of the normal TL. The PTTL intensity for peak I decreases as a function of heating rate. This decrease was attributed to thermal quenching. Thermal quenching was not observed in the case of the normal TL intensity. The cause of this contrast requires further study.
- Full Text:
- Date Issued: 2014
Tourism and development : a case study of Mdumbi Backpackers and Transcape non-profit organisation
- Authors: Hitchcock, Kelly Alexandra
- Date: 2014
- Subjects: Mdumbi Backpackers -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape -- Planning , Backpacking -- South Africa -- Eastern Cape -- Case studies , Black people -- Employment -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3377 , http://hdl.handle.net/10962/d1013143
- Description: The former Transkei region of the Eastern Cape of South Africa, in common with many of the other former Bantustans, is currently facing a developmental backlog. It is one of the poorest regions of the country and is a direct product of South Africa’s history of colonisation and geopolitical nature of apartheid in which people were forcibly located onto former tribal lands, called Bantustans. Tourism is one of the few business opportunities providing employment along the former Transkei coast. The tourism industry has been identified by many worldwide as a key strategy that can lead to economic upliftment, community development and poverty relief in the developing world. The predicament however, lies in the challenge of accepting or managing the negative consequences of tourism for the potential long term benefits offered by tourism-led development. Tourism development theory reflects development theory from traditional, top-down economic-growth based models to a more wide based approach with an emphasis on bottom-up planning, meeting of basic human need and a focus on sustainable development. Consequentially new and alternative forms of tourism have emerged and can be viewed as a response to some of the negative consequences of the mass tourism-led model of economic development. Backpacker tourism is one niche of the tourism market that is providing positive local socioeconomic benefits. This thesis is presented as a case study of Mdumbi Backpackers on the former Transkei coast. Mdumbi Backpackers is a unique example of a model of tourism that is providing meaningful benefits to the people who live in this community. By going one step further with the creation of the non-profit organisation Transcape, their involvement in the community has grown significantly, encouraging positive and sustainable development in the areas of social development, education and health. Mdumbi Backpackers goes beyond the notions of locally owned and sustainable approaches and actively encourages development by setting up community organisations and initiatives in a sustainable and equitable way. This approach to tourism-led development is well suited for the needs and objectives of the community as well preserving the natural environment. This thesis presents an exemplary example from which lessons can be learned and applied to developing tourism in a sustainable and equitable way in other rural communities.
- Full Text:
- Date Issued: 2014
- Authors: Hitchcock, Kelly Alexandra
- Date: 2014
- Subjects: Mdumbi Backpackers -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape -- Planning , Backpacking -- South Africa -- Eastern Cape -- Case studies , Black people -- Employment -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3377 , http://hdl.handle.net/10962/d1013143
- Description: The former Transkei region of the Eastern Cape of South Africa, in common with many of the other former Bantustans, is currently facing a developmental backlog. It is one of the poorest regions of the country and is a direct product of South Africa’s history of colonisation and geopolitical nature of apartheid in which people were forcibly located onto former tribal lands, called Bantustans. Tourism is one of the few business opportunities providing employment along the former Transkei coast. The tourism industry has been identified by many worldwide as a key strategy that can lead to economic upliftment, community development and poverty relief in the developing world. The predicament however, lies in the challenge of accepting or managing the negative consequences of tourism for the potential long term benefits offered by tourism-led development. Tourism development theory reflects development theory from traditional, top-down economic-growth based models to a more wide based approach with an emphasis on bottom-up planning, meeting of basic human need and a focus on sustainable development. Consequentially new and alternative forms of tourism have emerged and can be viewed as a response to some of the negative consequences of the mass tourism-led model of economic development. Backpacker tourism is one niche of the tourism market that is providing positive local socioeconomic benefits. This thesis is presented as a case study of Mdumbi Backpackers on the former Transkei coast. Mdumbi Backpackers is a unique example of a model of tourism that is providing meaningful benefits to the people who live in this community. By going one step further with the creation of the non-profit organisation Transcape, their involvement in the community has grown significantly, encouraging positive and sustainable development in the areas of social development, education and health. Mdumbi Backpackers goes beyond the notions of locally owned and sustainable approaches and actively encourages development by setting up community organisations and initiatives in a sustainable and equitable way. This approach to tourism-led development is well suited for the needs and objectives of the community as well preserving the natural environment. This thesis presents an exemplary example from which lessons can be learned and applied to developing tourism in a sustainable and equitable way in other rural communities.
- Full Text:
- Date Issued: 2014
Toward a culture of engagement: leveraging the enterprise social network
- Authors: Alistoun, Garth
- Date: 2014
- Subjects: Communication in organizations -- South Africa Business communication -- South Africa Social media -- South Africa -- Case studies Leadership -- South Africa -- Case studies Human capital -- Management Personnel management Organizational effectiveness
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1154 , http://hdl.handle.net/10962/d1010869
- Description: This research aims to provide a theory of enterprise social networking that generates and/or sustains a culture of employee engagement within a chosen South African private sector company. Based on an extensive review of interesting literature and the application of a grounded theory process in a chosen case, this research work provides a theory of enterprise social networking sustaining and growing employee engagement together with an explanatory theoretical framework that makes the theory more practical. Employee engagement is defined as “the harnessing of organisation member’s selves to their work roles; in engagement people employ and express themselves physically, cognitively, and emotionally during role performances.” This research regards employee engagement as a three part concept composed of a trait (personality/cognitive) aspect, a state (emotional) aspect, and a behavioural aspect. Research has shown that employee engagement has an unequivocal positive impact on business outcomes, such as profitability, business performance, employee retention and productivity. Employee engagement can be regarded as a culture if it is abundant within the organization’s employee population. Gatenby et al. (2009) propose that employee engagement is fostered by creating the desire and opportunity for employees to connect with colleagues, managers and the wider organisation. This standpoint is supported by Kular et al. (2008) who state that the “key drivers of employee engagement identified include communication, opportunities for employees to feed their views upward and thinking that their managers are committed to the organisation.” Further indicators of employee engagement include strong leadership (particularly in the form of servant leadership), accountability, a positive and open organisational culture, autonomy, and opportunities for development. One of the key facets of employee engagement is connection. A complementary definition of social media, an umbrella under which enterprise social networks fall, is that “(it) is more of a relationship channel, a connection channel. Each and every tweet, update, video, post, is a connection point to another human being. And it’s the other human being who will determine your worth to them.” Social media provides participants with access to a larger pool of resources and relationships than they would normally have access to. This enlarged relationship/resource pool is a result of expanding human and social capital enabled through social media tools. In order to produce a theory of enterprise social networking sustaining and growing a culture of employee engagement a rigorous grounded theory methodology coupled with a case study methodology was applied. The case study methodology was used to identify a suitable research site and interesting participants within the site while the grounded theory process was used to produce both qualitative and quantitative data sets in a suitability rigorous fashion. The corroborative data was then used to discover and define the emergent theory.
- Full Text:
- Date Issued: 2014
- Authors: Alistoun, Garth
- Date: 2014
- Subjects: Communication in organizations -- South Africa Business communication -- South Africa Social media -- South Africa -- Case studies Leadership -- South Africa -- Case studies Human capital -- Management Personnel management Organizational effectiveness
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1154 , http://hdl.handle.net/10962/d1010869
- Description: This research aims to provide a theory of enterprise social networking that generates and/or sustains a culture of employee engagement within a chosen South African private sector company. Based on an extensive review of interesting literature and the application of a grounded theory process in a chosen case, this research work provides a theory of enterprise social networking sustaining and growing employee engagement together with an explanatory theoretical framework that makes the theory more practical. Employee engagement is defined as “the harnessing of organisation member’s selves to their work roles; in engagement people employ and express themselves physically, cognitively, and emotionally during role performances.” This research regards employee engagement as a three part concept composed of a trait (personality/cognitive) aspect, a state (emotional) aspect, and a behavioural aspect. Research has shown that employee engagement has an unequivocal positive impact on business outcomes, such as profitability, business performance, employee retention and productivity. Employee engagement can be regarded as a culture if it is abundant within the organization’s employee population. Gatenby et al. (2009) propose that employee engagement is fostered by creating the desire and opportunity for employees to connect with colleagues, managers and the wider organisation. This standpoint is supported by Kular et al. (2008) who state that the “key drivers of employee engagement identified include communication, opportunities for employees to feed their views upward and thinking that their managers are committed to the organisation.” Further indicators of employee engagement include strong leadership (particularly in the form of servant leadership), accountability, a positive and open organisational culture, autonomy, and opportunities for development. One of the key facets of employee engagement is connection. A complementary definition of social media, an umbrella under which enterprise social networks fall, is that “(it) is more of a relationship channel, a connection channel. Each and every tweet, update, video, post, is a connection point to another human being. And it’s the other human being who will determine your worth to them.” Social media provides participants with access to a larger pool of resources and relationships than they would normally have access to. This enlarged relationship/resource pool is a result of expanding human and social capital enabled through social media tools. In order to produce a theory of enterprise social networking sustaining and growing a culture of employee engagement a rigorous grounded theory methodology coupled with a case study methodology was applied. The case study methodology was used to identify a suitable research site and interesting participants within the site while the grounded theory process was used to produce both qualitative and quantitative data sets in a suitability rigorous fashion. The corroborative data was then used to discover and define the emergent theory.
- Full Text:
- Date Issued: 2014
Towards sustainable municipalities : an evaluation of sustainability integration in Elundini Local Municipality strategy
- Authors: Sokutu, Nonkuselo
- Date: 2014
- Subjects: Municipal government -- South Africa -- Eastern Cape , Strategic planning -- South Africa -- Eastern Cape , Sustainability -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Sustainable development -- Social aspects -- South Africa -- Eastern Cape , Sustainable development -- Environmental aspects -- South Africa -- Eastern Cape , Sustainable development -- Economic aspects -- South Africa -- Eastern Cape , Environmental impact analysis -- South Africa -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:830 , http://hdl.handle.net/10962/d1013018
- Description: This research study evaluated and assessed the extent to which strategic management processes integrated economic, environmental and social sustainability elements in the fiveyear strategy (2012) of Elundini Local Municipality (ELM). The study focused on three areas of strategic management, that is, environmental analysis, strategic direction and strategy formulation. The study also looked at possible reasons for sustainability integration in ELM strategy or lack thereof and also recommended possible solutions. The literature reviewed revealed that there was adequate basis for municipalities to integrate sustainable development in their strategies even though sustainability was noted as an evolving, complex and changing phenomenon. Local Agenda 21 principles, national legislative & policy framework, regulations and other relevant guidelines were found to be adequate for municipalities to develop credible sustainability strategies. The objectives of the study were achieved by data collected through the review of existing literature; the review of ELM Five Year Strategy (2012-2017); and SIAT-based questionnaires that were filled in by ELM employees. The results of the study showed that economic and social sustainability activities were identified most in the ELM strategy compared to environmental sustainability. The study then mainly recommended the review of the current strategy in order to improve all areas of strategy formulation; introduction of Economic, Social and Environmental sustainability – Strengths, Weaknesses, Opportunities and Threats (ESEs-SWOT) for internal analysis as an improvement of SWOT analysis; introduction of Sustainability Integration and Strategic Management Framework (SISMF) as an improvement to existing framework.
- Full Text:
- Date Issued: 2014
- Authors: Sokutu, Nonkuselo
- Date: 2014
- Subjects: Municipal government -- South Africa -- Eastern Cape , Strategic planning -- South Africa -- Eastern Cape , Sustainability -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Sustainable development -- Social aspects -- South Africa -- Eastern Cape , Sustainable development -- Environmental aspects -- South Africa -- Eastern Cape , Sustainable development -- Economic aspects -- South Africa -- Eastern Cape , Environmental impact analysis -- South Africa -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:830 , http://hdl.handle.net/10962/d1013018
- Description: This research study evaluated and assessed the extent to which strategic management processes integrated economic, environmental and social sustainability elements in the fiveyear strategy (2012) of Elundini Local Municipality (ELM). The study focused on three areas of strategic management, that is, environmental analysis, strategic direction and strategy formulation. The study also looked at possible reasons for sustainability integration in ELM strategy or lack thereof and also recommended possible solutions. The literature reviewed revealed that there was adequate basis for municipalities to integrate sustainable development in their strategies even though sustainability was noted as an evolving, complex and changing phenomenon. Local Agenda 21 principles, national legislative & policy framework, regulations and other relevant guidelines were found to be adequate for municipalities to develop credible sustainability strategies. The objectives of the study were achieved by data collected through the review of existing literature; the review of ELM Five Year Strategy (2012-2017); and SIAT-based questionnaires that were filled in by ELM employees. The results of the study showed that economic and social sustainability activities were identified most in the ELM strategy compared to environmental sustainability. The study then mainly recommended the review of the current strategy in order to improve all areas of strategy formulation; introduction of Economic, Social and Environmental sustainability – Strengths, Weaknesses, Opportunities and Threats (ESEs-SWOT) for internal analysis as an improvement of SWOT analysis; introduction of Sustainability Integration and Strategic Management Framework (SISMF) as an improvement to existing framework.
- Full Text:
- Date Issued: 2014
Towards the feasibility of a landowner enterprise in the western Baviaanskloof : an external stakeholder analysis
- Authors: Wiles, Kira Leigh Deborah
- Date: 2014
- Subjects: Landowners -- South Africa -- Eastern Cape , Natural resources -- Co-management -- South Africa -- Eastern Cape , Land use -- Environmental aspects -- South Africa -- Eastern Cape , Land use -- Economic aspects -- South Africa -- Eastern Cape , Partnership -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1198 , http://hdl.handle.net/10962/d1012075 , Landowners -- South Africa -- Eastern Cape , Natural resources -- Co-management -- South Africa -- Eastern Cape , Land use -- Environmental aspects -- South Africa -- Eastern Cape , Land use -- Economic aspects -- South Africa -- Eastern Cape , Partnership -- South Africa -- Eastern Cape
- Description: In May 2012, a meeting was held between various stakeholder representatives of the Western Baviaanskloof to discuss the concept of a proposed landowner-enterprise. This concept was put forward in response to a need for collaboration in the midst of economic, environmental and social issues at play in the Baviaanskloof. Owing to the conservation value and rapidly decreasing economic output of the land, a radical shift to sustainable land-use practices was called for by various stakeholders. Suggested as a vehicle to generate income for the local landowners through alternative sustainable land-uses, the proposed enterprise may aid in addressing this shift by use of a bottom-up approach. During the stakeholder meeting, it was requested by the representative landowners that a feasibility assessment be conducted on the concept of the proposed enterprise prior to establishment. As an integral part of this assessment, the researcher took on the task of investigating stakeholder reception to the enterprise by means of a stakeholder analysis. It was decided to limit this to three markets: water, carbon and tourism. The purpose of this research study is twofold, namely to: investigate stakeholder influence and their reception of the proposed enterprise using a stakeholder analysis; and also to identify and advise on the opportunities and constraints relating to stakeholders, thus contributing to determining the feasibility of the proposed enterprise. In achieving the purpose of this study, a systematic stakeholder analysis framework was constructed, based on existing theory. This was necessary because, although stakeholder analysis is commonly practiced, no study was found to provide a theoretically based framework for the purpose of feasibility in the initial stages of enterprise establishment. Thus the contribution of the study is also twofold, namely the practical outcome of determining stakeholder reception for feasibility, and a secondary outcome of constructing a stakeholder analysis framework. The stakeholder analysis framework is based on an interpretation of existing stakeholder theory, with the addition of four "relational indicators" – goals, intentions, relationships, and resources. These four indicators provide a link between theory and practice in gauging the two attributes of stakeholder influence – power and interest. Dealing with a number of stakeholder interests in a unique context, the study takes on a single network case study approach in the paradigm of phenomenology. To suit the complex nature of the study, semi-structured interviews with various stakeholder representatives were conducted, using groups or organisations as units of analysis. Drawing from the stakeholder analysis framework and overall purpose of the study, four research objectives were set. The first was to identify the proposed enterprise's legitimate key external stakeholders, based on the three markets: water, carbon and tourism; the second to describe, categorise and assess relative dyadic influence of the above stakeholders by gauging their power and interest; the third, to determine the stakeholder network influence and probable reception of the proposed enterprise; and the last to advise the landowners on any identified opportunities or constraints stakeholders might pose, and thus to contribute to determining feasibility. In addressing the first objective, 21 stakeholders were identified, 12 of whom were found to be key to the current investigation. These key stakeholders were: Gamtoos Irrigation Board (GIB), LivingLands, R3G, Rhodes Restoration Group, Eastern Cape Parks and Tourism Agency (ECPTA), Department of Water Affairs (DWA), Nelson Mandela Bay Metropolitan (NMBM), Saaimanshoek, South African National Biodiversity Institute (SANBI), Department of Economic Development, Environmental Affairs and Tourism (DEDEAT), Baviaans Tourism, and Baviaans Municipality. In applying the stakeholder analysis framework, ECPTA was categorised as the definitive (most influential) stakeholder to the enterprise, and DEDEAT, SANBI (through Working for Wetlands), Baviaans Tourism, GIB, and NMBM were categorised as pivotal (influential and active). In discerning stakeholder interest in the proposed enterprise, a number of emerging themes were found to affect the projected interest and behaviour of stakeholders, apart from their specified goals. Emerging themes included: tunnel visioning, internal disparity, individual/personality clashes, and misaligned interests. In addition to this, in interpreting stakeholder interest, specific intentions or agendas that might affect the interest shown towards the proposed enterprise were also taken into account. Five predominant intentions of stakeholders were identified as: implementing a stewardship programme, establishing a tourism association, establishing a water users' association, social development, and "the big vision". Findings on the final objective revealed a number of perceived opportunities and constraints relative to the feasibility of the enterprise. Three prime opportunities were identified as: partnerships with definitive and pivotal stakeholders, the possibility of tendering for implementer of the "Working for" programmes, and taking on the role of Tourism Association. The following potential constraints were also emphasised by participants: social aspects such as individuals and personalities, the incompatibility or non-existence of local market structures, and the need for external funding. With regard to stakeholder reception, most of the stakeholders, with the exception of NMBM and Saaimanshoek, responded positively to the idea of the enterprise. Overall, based on participant perceptions, the tourism market was found to be the most feasible the carbon market uncertain and a long-term possibility, and the water market the least feasible.
- Full Text:
- Date Issued: 2014
- Authors: Wiles, Kira Leigh Deborah
- Date: 2014
- Subjects: Landowners -- South Africa -- Eastern Cape , Natural resources -- Co-management -- South Africa -- Eastern Cape , Land use -- Environmental aspects -- South Africa -- Eastern Cape , Land use -- Economic aspects -- South Africa -- Eastern Cape , Partnership -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1198 , http://hdl.handle.net/10962/d1012075 , Landowners -- South Africa -- Eastern Cape , Natural resources -- Co-management -- South Africa -- Eastern Cape , Land use -- Environmental aspects -- South Africa -- Eastern Cape , Land use -- Economic aspects -- South Africa -- Eastern Cape , Partnership -- South Africa -- Eastern Cape
- Description: In May 2012, a meeting was held between various stakeholder representatives of the Western Baviaanskloof to discuss the concept of a proposed landowner-enterprise. This concept was put forward in response to a need for collaboration in the midst of economic, environmental and social issues at play in the Baviaanskloof. Owing to the conservation value and rapidly decreasing economic output of the land, a radical shift to sustainable land-use practices was called for by various stakeholders. Suggested as a vehicle to generate income for the local landowners through alternative sustainable land-uses, the proposed enterprise may aid in addressing this shift by use of a bottom-up approach. During the stakeholder meeting, it was requested by the representative landowners that a feasibility assessment be conducted on the concept of the proposed enterprise prior to establishment. As an integral part of this assessment, the researcher took on the task of investigating stakeholder reception to the enterprise by means of a stakeholder analysis. It was decided to limit this to three markets: water, carbon and tourism. The purpose of this research study is twofold, namely to: investigate stakeholder influence and their reception of the proposed enterprise using a stakeholder analysis; and also to identify and advise on the opportunities and constraints relating to stakeholders, thus contributing to determining the feasibility of the proposed enterprise. In achieving the purpose of this study, a systematic stakeholder analysis framework was constructed, based on existing theory. This was necessary because, although stakeholder analysis is commonly practiced, no study was found to provide a theoretically based framework for the purpose of feasibility in the initial stages of enterprise establishment. Thus the contribution of the study is also twofold, namely the practical outcome of determining stakeholder reception for feasibility, and a secondary outcome of constructing a stakeholder analysis framework. The stakeholder analysis framework is based on an interpretation of existing stakeholder theory, with the addition of four "relational indicators" – goals, intentions, relationships, and resources. These four indicators provide a link between theory and practice in gauging the two attributes of stakeholder influence – power and interest. Dealing with a number of stakeholder interests in a unique context, the study takes on a single network case study approach in the paradigm of phenomenology. To suit the complex nature of the study, semi-structured interviews with various stakeholder representatives were conducted, using groups or organisations as units of analysis. Drawing from the stakeholder analysis framework and overall purpose of the study, four research objectives were set. The first was to identify the proposed enterprise's legitimate key external stakeholders, based on the three markets: water, carbon and tourism; the second to describe, categorise and assess relative dyadic influence of the above stakeholders by gauging their power and interest; the third, to determine the stakeholder network influence and probable reception of the proposed enterprise; and the last to advise the landowners on any identified opportunities or constraints stakeholders might pose, and thus to contribute to determining feasibility. In addressing the first objective, 21 stakeholders were identified, 12 of whom were found to be key to the current investigation. These key stakeholders were: Gamtoos Irrigation Board (GIB), LivingLands, R3G, Rhodes Restoration Group, Eastern Cape Parks and Tourism Agency (ECPTA), Department of Water Affairs (DWA), Nelson Mandela Bay Metropolitan (NMBM), Saaimanshoek, South African National Biodiversity Institute (SANBI), Department of Economic Development, Environmental Affairs and Tourism (DEDEAT), Baviaans Tourism, and Baviaans Municipality. In applying the stakeholder analysis framework, ECPTA was categorised as the definitive (most influential) stakeholder to the enterprise, and DEDEAT, SANBI (through Working for Wetlands), Baviaans Tourism, GIB, and NMBM were categorised as pivotal (influential and active). In discerning stakeholder interest in the proposed enterprise, a number of emerging themes were found to affect the projected interest and behaviour of stakeholders, apart from their specified goals. Emerging themes included: tunnel visioning, internal disparity, individual/personality clashes, and misaligned interests. In addition to this, in interpreting stakeholder interest, specific intentions or agendas that might affect the interest shown towards the proposed enterprise were also taken into account. Five predominant intentions of stakeholders were identified as: implementing a stewardship programme, establishing a tourism association, establishing a water users' association, social development, and "the big vision". Findings on the final objective revealed a number of perceived opportunities and constraints relative to the feasibility of the enterprise. Three prime opportunities were identified as: partnerships with definitive and pivotal stakeholders, the possibility of tendering for implementer of the "Working for" programmes, and taking on the role of Tourism Association. The following potential constraints were also emphasised by participants: social aspects such as individuals and personalities, the incompatibility or non-existence of local market structures, and the need for external funding. With regard to stakeholder reception, most of the stakeholders, with the exception of NMBM and Saaimanshoek, responded positively to the idea of the enterprise. Overall, based on participant perceptions, the tourism market was found to be the most feasible the carbon market uncertain and a long-term possibility, and the water market the least feasible.
- Full Text:
- Date Issued: 2014
Towards understanding the effects of stocking density on farmed South African abalone, Haliotis Midae
- Authors: Nicholson, Gareth Hurst
- Date: 2014
- Subjects: Haliotis midae -- South Africa , Haliotis midae fisheries -- South Africa , Abalones -- South Africa , Fish stocking -- South Africa , Abalone populations -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5371 , http://hdl.handle.net/10962/d1015646
- Description: The profitability of abalone farms is heavily influenced by their production per unit of grow-out space. With farms having physically expanded to the maximum, and with increasing production costs, one of the most realistic ways for farms to increase their production is through optimizing stocking densities. The effect of stocking density on Haliotis midae performance is undocumented and optimal stocking densities for this species have not been determined. Experiments were conducted under farm conditions to investigate the effects of four different stocking densities (16 %, 20 %, 22 % and 24 % of available surface area) on growth, production and health of three different size classes of abalone (15-35 g, 45-65 g, and 70-90 g start weight). Each treatment was replicated four times and trials ran over a period of eight months with measurements being made at four month intervals. Abalone behaviour was observed during the trials in the experimental tanks. Weight gain per abalone decreased with an increase in density for all tested size classes (5.04 ± 0.18 to 2.38 ± 0.17; 5.35 ± 0.21 to 4.62 ± 0.29; 7.97 ± 0.37 to 6.53 ± 0.28 g.abalone-1.month-1 for the 15-35, 45-65 and 70-90 g classes respectively, with an increased density of 16 to 24 %). Individual weight gain of 15-35 g abalone was similar at stocking densities of 16 % and 20 % while weight gain of 45-65 g and 70-90 g abalone decreased when density was increased above 16 %. Biomass gain (kg.basket-1.month-1) was not affected by stocking density in the 15-35 g and 45-65 g size classes (1.29 ± 0.02 and 0.97 ± 0.02 kg.basket-1.month-1 respectively). However, the biomass gained by baskets stocked with 70-90 g abalone increased with stocking density (1.08 ± 0.02 to 1.33 ± 0.02 kg.basket-1.month-1) with an increased density of 16 to 24 %) and did not appear to plateau within the tested density range (16 to 24 %). Food conversion ratio did not differ significantly between densities across all size classes. Stocking density did not have a significant effect on abalone condition factor or health indices. The proportion of abalone above the level of the feeder plate increased with density (7.26 ± 1.33 to 16.44 ± 1.33 with an increased density of 16 to 24 %). As a proportion of abalone situated in the area of the basket, the same proportions were situated on the walls above the feeder plate and on the feeder plate itself irrespective of stocking density (p > 0.05). Higher proportions of animals had restricted access to feed at higher stocking densities (p = 0.03). The amount of formulated feed available on the feeder plate did not differ between stocking densities throughout the night (p = 0.19). Individual abalone spent more time above the feeder plate at higher stocking densities (p < 0.05). The percentage of time above the feeder plate, spent on the walls of the basket and on the feeding surface was not significantly different at densities of 20 %, 22 % and 24 % (p > 0.05) but abalone stocked at 16 % spent a greater percentage of time above the feeder plate on the feeding surface (83.99 ± 6.26 %) than on the basket walls (16.01 ± 6.26 %). Stocking density did not affect the positioning of abalone within a basket during the day or at night. Different size H. midae are affected differently by increases in stocking density in terms of growth performance. Findings from this research may be implemented into farm management strategies to best suit production goals, whether in terms of biomass production or individual weight gain. The fundamental mechanisms resulting in reduced growth at higher densities are not well understood, however results from behaviour observations suggest that competition for preferred attachment space and feed availability are contributing to decreased growth rates. With knowledge of abalone behaviour at different densities, innovative tank designs may be established in order to counter the reduction in growth at higher densities.
- Full Text:
- Date Issued: 2014
- Authors: Nicholson, Gareth Hurst
- Date: 2014
- Subjects: Haliotis midae -- South Africa , Haliotis midae fisheries -- South Africa , Abalones -- South Africa , Fish stocking -- South Africa , Abalone populations -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5371 , http://hdl.handle.net/10962/d1015646
- Description: The profitability of abalone farms is heavily influenced by their production per unit of grow-out space. With farms having physically expanded to the maximum, and with increasing production costs, one of the most realistic ways for farms to increase their production is through optimizing stocking densities. The effect of stocking density on Haliotis midae performance is undocumented and optimal stocking densities for this species have not been determined. Experiments were conducted under farm conditions to investigate the effects of four different stocking densities (16 %, 20 %, 22 % and 24 % of available surface area) on growth, production and health of three different size classes of abalone (15-35 g, 45-65 g, and 70-90 g start weight). Each treatment was replicated four times and trials ran over a period of eight months with measurements being made at four month intervals. Abalone behaviour was observed during the trials in the experimental tanks. Weight gain per abalone decreased with an increase in density for all tested size classes (5.04 ± 0.18 to 2.38 ± 0.17; 5.35 ± 0.21 to 4.62 ± 0.29; 7.97 ± 0.37 to 6.53 ± 0.28 g.abalone-1.month-1 for the 15-35, 45-65 and 70-90 g classes respectively, with an increased density of 16 to 24 %). Individual weight gain of 15-35 g abalone was similar at stocking densities of 16 % and 20 % while weight gain of 45-65 g and 70-90 g abalone decreased when density was increased above 16 %. Biomass gain (kg.basket-1.month-1) was not affected by stocking density in the 15-35 g and 45-65 g size classes (1.29 ± 0.02 and 0.97 ± 0.02 kg.basket-1.month-1 respectively). However, the biomass gained by baskets stocked with 70-90 g abalone increased with stocking density (1.08 ± 0.02 to 1.33 ± 0.02 kg.basket-1.month-1) with an increased density of 16 to 24 %) and did not appear to plateau within the tested density range (16 to 24 %). Food conversion ratio did not differ significantly between densities across all size classes. Stocking density did not have a significant effect on abalone condition factor or health indices. The proportion of abalone above the level of the feeder plate increased with density (7.26 ± 1.33 to 16.44 ± 1.33 with an increased density of 16 to 24 %). As a proportion of abalone situated in the area of the basket, the same proportions were situated on the walls above the feeder plate and on the feeder plate itself irrespective of stocking density (p > 0.05). Higher proportions of animals had restricted access to feed at higher stocking densities (p = 0.03). The amount of formulated feed available on the feeder plate did not differ between stocking densities throughout the night (p = 0.19). Individual abalone spent more time above the feeder plate at higher stocking densities (p < 0.05). The percentage of time above the feeder plate, spent on the walls of the basket and on the feeding surface was not significantly different at densities of 20 %, 22 % and 24 % (p > 0.05) but abalone stocked at 16 % spent a greater percentage of time above the feeder plate on the feeding surface (83.99 ± 6.26 %) than on the basket walls (16.01 ± 6.26 %). Stocking density did not affect the positioning of abalone within a basket during the day or at night. Different size H. midae are affected differently by increases in stocking density in terms of growth performance. Findings from this research may be implemented into farm management strategies to best suit production goals, whether in terms of biomass production or individual weight gain. The fundamental mechanisms resulting in reduced growth at higher densities are not well understood, however results from behaviour observations suggest that competition for preferred attachment space and feed availability are contributing to decreased growth rates. With knowledge of abalone behaviour at different densities, innovative tank designs may be established in order to counter the reduction in growth at higher densities.
- Full Text:
- Date Issued: 2014
Trends in the fish assemblage structure of two South African transition-zone estuaries : can these trends be linked to climate change?
- Authors: Midgley, Craig
- Date: 2014
- Subjects: Estuarine fishes -- South Africa -- Climatic factors , Fish communities -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5368 , http://hdl.handle.net/10962/d1013173
- Description: Changes in the fish communities of the Breede and Mbashe estuaries were investigated in relation to the environmental variables that influence the fish assemblages in these systems. The Breede Estuary (34° 24’21.6”S, 20° 51’ 08.2”E) occurs within the warm-temperate/cool-temperate transition-zone, while the Mbashe Estuary (32o 14' 55.4"S, 28o 54' 03.7"E) falls within the subtropical/warm-temperate transition-zone along the South African coastline. The Breede Estuary was sampled (seine and gill nets) during summer (January-March) over a period of 10 years (2002-2012), while the Mbashe Estuary was sampled (seine net) during spring (October) over a period of three years (2010-2012). The proportion of tropical fish species was higher in the Mbashe Estuary compared to the Breede Estuary, while the Breede Estuary contained a higher proportion of temperate species than the Mbashe Estuary. Although the abundance of individual species in both estuaries varied, the ranking of species in the Breede Estuary was stable over the 10 year period. Multivariate analysis showed that the fish communities within each reach (upper, middle, lower) of the Breede Estuary remained similar, regardless of year. In contrast, species composition in the Mbashe Estuary differed significantly between years mainly due to differences in the river flow regime during the study period. Environmental variables responsible for structuring the fish assemblage in each estuary differed. Salinity significantly impacted the spatial fish assemblage structure of the Breede Estuary, with most of the species recorded being associated with the more saline lower reaches. The abundance of tropical species near their distributional limit in the Breede Estuary appeared to be impacted by sea surface temperature (SST) as peak total abundance of these species coincided with the warmest SST, while the lowest total abundance coincided with the coldest annual SST during the study period. The fish assemblage structure in the Mbashe Estuary was impacted by differing freshwater input prior to sampling, with flooding negatively impacting the mean total abundance, species composition and diversity in this system. The variables that influenced the fish assemblage structure of both transition-zone estuaries will be affected by climate change in the future. These variables will, in turn, determine the composition, abundance and diversity of species within these important estuarine systems. In order to measure these impacts with any degree of understanding, long-term studies on the abiotic and biotic (including the ichthyofauna) features of these estuaries are required to interpret climate change trends.
- Full Text:
- Date Issued: 2014
- Authors: Midgley, Craig
- Date: 2014
- Subjects: Estuarine fishes -- South Africa -- Climatic factors , Fish communities -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5368 , http://hdl.handle.net/10962/d1013173
- Description: Changes in the fish communities of the Breede and Mbashe estuaries were investigated in relation to the environmental variables that influence the fish assemblages in these systems. The Breede Estuary (34° 24’21.6”S, 20° 51’ 08.2”E) occurs within the warm-temperate/cool-temperate transition-zone, while the Mbashe Estuary (32o 14' 55.4"S, 28o 54' 03.7"E) falls within the subtropical/warm-temperate transition-zone along the South African coastline. The Breede Estuary was sampled (seine and gill nets) during summer (January-March) over a period of 10 years (2002-2012), while the Mbashe Estuary was sampled (seine net) during spring (October) over a period of three years (2010-2012). The proportion of tropical fish species was higher in the Mbashe Estuary compared to the Breede Estuary, while the Breede Estuary contained a higher proportion of temperate species than the Mbashe Estuary. Although the abundance of individual species in both estuaries varied, the ranking of species in the Breede Estuary was stable over the 10 year period. Multivariate analysis showed that the fish communities within each reach (upper, middle, lower) of the Breede Estuary remained similar, regardless of year. In contrast, species composition in the Mbashe Estuary differed significantly between years mainly due to differences in the river flow regime during the study period. Environmental variables responsible for structuring the fish assemblage in each estuary differed. Salinity significantly impacted the spatial fish assemblage structure of the Breede Estuary, with most of the species recorded being associated with the more saline lower reaches. The abundance of tropical species near their distributional limit in the Breede Estuary appeared to be impacted by sea surface temperature (SST) as peak total abundance of these species coincided with the warmest SST, while the lowest total abundance coincided with the coldest annual SST during the study period. The fish assemblage structure in the Mbashe Estuary was impacted by differing freshwater input prior to sampling, with flooding negatively impacting the mean total abundance, species composition and diversity in this system. The variables that influenced the fish assemblage structure of both transition-zone estuaries will be affected by climate change in the future. These variables will, in turn, determine the composition, abundance and diversity of species within these important estuarine systems. In order to measure these impacts with any degree of understanding, long-term studies on the abiotic and biotic (including the ichthyofauna) features of these estuaries are required to interpret climate change trends.
- Full Text:
- Date Issued: 2014