Exploration status for oxide and sulphide zinc ores at Skorpion Zinc Mine, Namibia
- Authors: Sitoka, Stefanus
- Date: 2015
- Subjects: Scorpion Zinc Mine (Namibia) , Zinc ores , Oxide minerals , Sulfide minerals , Zinc mines and mining -- Namibia , Prospecting -- Namibia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5087 , http://hdl.handle.net/10962/d1018204
- Description: The thesis is inspired by recent interests in oxide zinc ores caused by new developments in the technology of hydrometallurgy. The improved techniques turned the non-sulphide zinc ores in to attractive exploration targets due to a number of advantages such as low metal recovery costs and favorable environmental aspects such as the obvious absence of sulfur (Large, 2001). Historically extraction of zinc metal from oxide ores was not possible until recently. The metallurgical complexity resulted in a lack of interest and hence some economic oxide zinc ores might have been missed by conventional exploration techniques. The study presents a review of exploration status at Skorpion mine based on different exploration techniques and their application to sulphide and oxide zinc ore exploration. The challenge facing the mineral exploration industry today is the inability to detect mineral deposits under cover. Therefore a key to successful exploration program lies in the selection of the right exploration technique. Important parameters that should be highlighted in the exploration methodology are the geological situation of an area, equipment applicability and effectiveness, survey limitation, equipment mobilization and the safety aspects involved. The aim of this thesis is to provide a general guideline for sulphide and non-sulphide zinc ore exploration on the Skorpion area and other similar geological environments. Geochemical surveys appears to be more complimentary in exploration of non-sulphide zinc exploration. Although geochemical techniques are preferred, it is equally important to choose the right soil horizon. Furthermore, sample media may mean the difference between success and failure in geochemical exploration of non-sulphide zinc mineralization, due to high mobility of zinc in the surficial environment. On cost comparison, surface geochemical surveys programs are more cost effective except for litho-geochemical sampling which are commonly carried out through subsurface drilling. Geophysical techniques have limited application in exploration of non-sulphide zinc mineralization due to a lack of major physical properties (e.g., magnetic and electrical properties) in non-sulphides unlike their sulphide counterparts. However geophysical methods are commendable in delineating massive and disseminated sulphides mainly if they are associated with major Fe minerals (pyrrhotite or magnetite). In addition, geophysical techniques may be effective in mapping of subsurface primary and secondary structures such as basin faults which might have acted as pathways for metal-rich fluids. Terms non-sulphide and oxide zinc mineralization are used interchangeably throughout the thesis. Recommendations on regional and local target generation are presented in the thesis to give some basic guide lines on target generation strategies. The most important conclusion reached in this study is that, success in exploration for non-sulphide or sulphide zinc mineralization might be enhanced through the integrated exploration methodology.
- Full Text:
- Authors: Sitoka, Stefanus
- Date: 2015
- Subjects: Scorpion Zinc Mine (Namibia) , Zinc ores , Oxide minerals , Sulfide minerals , Zinc mines and mining -- Namibia , Prospecting -- Namibia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5087 , http://hdl.handle.net/10962/d1018204
- Description: The thesis is inspired by recent interests in oxide zinc ores caused by new developments in the technology of hydrometallurgy. The improved techniques turned the non-sulphide zinc ores in to attractive exploration targets due to a number of advantages such as low metal recovery costs and favorable environmental aspects such as the obvious absence of sulfur (Large, 2001). Historically extraction of zinc metal from oxide ores was not possible until recently. The metallurgical complexity resulted in a lack of interest and hence some economic oxide zinc ores might have been missed by conventional exploration techniques. The study presents a review of exploration status at Skorpion mine based on different exploration techniques and their application to sulphide and oxide zinc ore exploration. The challenge facing the mineral exploration industry today is the inability to detect mineral deposits under cover. Therefore a key to successful exploration program lies in the selection of the right exploration technique. Important parameters that should be highlighted in the exploration methodology are the geological situation of an area, equipment applicability and effectiveness, survey limitation, equipment mobilization and the safety aspects involved. The aim of this thesis is to provide a general guideline for sulphide and non-sulphide zinc ore exploration on the Skorpion area and other similar geological environments. Geochemical surveys appears to be more complimentary in exploration of non-sulphide zinc exploration. Although geochemical techniques are preferred, it is equally important to choose the right soil horizon. Furthermore, sample media may mean the difference between success and failure in geochemical exploration of non-sulphide zinc mineralization, due to high mobility of zinc in the surficial environment. On cost comparison, surface geochemical surveys programs are more cost effective except for litho-geochemical sampling which are commonly carried out through subsurface drilling. Geophysical techniques have limited application in exploration of non-sulphide zinc mineralization due to a lack of major physical properties (e.g., magnetic and electrical properties) in non-sulphides unlike their sulphide counterparts. However geophysical methods are commendable in delineating massive and disseminated sulphides mainly if they are associated with major Fe minerals (pyrrhotite or magnetite). In addition, geophysical techniques may be effective in mapping of subsurface primary and secondary structures such as basin faults which might have acted as pathways for metal-rich fluids. Terms non-sulphide and oxide zinc mineralization are used interchangeably throughout the thesis. Recommendations on regional and local target generation are presented in the thesis to give some basic guide lines on target generation strategies. The most important conclusion reached in this study is that, success in exploration for non-sulphide or sulphide zinc mineralization might be enhanced through the integrated exploration methodology.
- Full Text:
Exploring Grade 12 biology teachers' perceptions and experiences of the dissemination and utilization of Examiners' reports in the Khomas region of Namibia: a case study
- Authors: Bezuidenhoudt, Anthea
- Date: 2015
- Subjects: Biology -- Examinations -- Namibia , Biology -- Study and teaching -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2021 , http://hdl.handle.net/10962/d1017332
- Description: Teachers’ perceptions are that currently dissemination in schools is ineffective and must change. The tensions that surround the dissemination of the reports are late arrival of Examiners’ reports which clash with preparation of learners for the first term examinations. Furthermore, the time the Examiners’ reports get into teachers’ hands are late and thus result in teachers rushing through it to incorporate the recommendations given in it in the second term or in some instances teachers do not attend to it at all. The number of copies of the Examiners’ reports provided to schools appears to be inadequate. HODs still having to duplicate reports before disseminating them add to their work load and further delay dissemination of the reports to individual subject teachers. Although the teaching and learning approach in Namibian classrooms should be based on LCE, dissemination of the actual physical reports are currently restricted to teachers only with them only verbally communicating feedback given in the reports to their learners. Support in dissemination of Examiners’ reports from peers and superiors in the majority of the schools appear to be lacking. Changes would like to be seen in the timing the Examiners’ reports are available at schools, the number of hard copies provided to schools and exploring and embarking on alternative ways of disseminating the reports. The percentage of utilization of the Examiners’ reports is relatively high, yet still not the optimum. A reasonable number of Namibian learners are disadvantaged and not exposed to a source of information that can make their Biology learning more efficient because some of their teachers are not using Examiners’ reports in their teaching. The main reason for non-utilization of the reports by Biology teachers is a result of inefficient dissemination at individual schools. The argument being that if the reports are not given to the teachers they and especially novice teachers will not know about the existence of this useful teaching and learning resource. Examiners’ reports are an important and systematic impartial source of high quality data on learning in the Namibian education system. Therefore, effective dissemination and utilization of the reports must be advocated and strengthened. DNEA and the Khomas regional office should embark on tapping into available development in information technology by doing research into the possibility of disseminating the Examiners’ reports electronically. A pilot in this regard should be conducted in the Khomas region as a measure to ensure dissemination can become more efficient in the future. To ensure that teachers optimally utilize the Examiners’ reports, they should be provided to schools when the school first term commences. The Khomas regional office should strengthen their involvement in utilization by arranging annual workshops where the content of the reports can be discussed to ensure that the feedback given in the reports can aid in developing and strengthening Biology teachers’ subject content knowledge as well as pedagogical content knowledge. Optimal utilization of Examiners’ reports can enable mediation in learners which can ensure effective learning and mastery of Biology by learners which can ultimately lead to an improvement in pass rate in Biology. Therefore, appropriate support to aid teachers’ professional development can enhance maximum utilization. Furthermore, an area for future research could be to give the Examiners’ reports to learners to determine the impact it has on their learning.
- Full Text:
- Authors: Bezuidenhoudt, Anthea
- Date: 2015
- Subjects: Biology -- Examinations -- Namibia , Biology -- Study and teaching -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2021 , http://hdl.handle.net/10962/d1017332
- Description: Teachers’ perceptions are that currently dissemination in schools is ineffective and must change. The tensions that surround the dissemination of the reports are late arrival of Examiners’ reports which clash with preparation of learners for the first term examinations. Furthermore, the time the Examiners’ reports get into teachers’ hands are late and thus result in teachers rushing through it to incorporate the recommendations given in it in the second term or in some instances teachers do not attend to it at all. The number of copies of the Examiners’ reports provided to schools appears to be inadequate. HODs still having to duplicate reports before disseminating them add to their work load and further delay dissemination of the reports to individual subject teachers. Although the teaching and learning approach in Namibian classrooms should be based on LCE, dissemination of the actual physical reports are currently restricted to teachers only with them only verbally communicating feedback given in the reports to their learners. Support in dissemination of Examiners’ reports from peers and superiors in the majority of the schools appear to be lacking. Changes would like to be seen in the timing the Examiners’ reports are available at schools, the number of hard copies provided to schools and exploring and embarking on alternative ways of disseminating the reports. The percentage of utilization of the Examiners’ reports is relatively high, yet still not the optimum. A reasonable number of Namibian learners are disadvantaged and not exposed to a source of information that can make their Biology learning more efficient because some of their teachers are not using Examiners’ reports in their teaching. The main reason for non-utilization of the reports by Biology teachers is a result of inefficient dissemination at individual schools. The argument being that if the reports are not given to the teachers they and especially novice teachers will not know about the existence of this useful teaching and learning resource. Examiners’ reports are an important and systematic impartial source of high quality data on learning in the Namibian education system. Therefore, effective dissemination and utilization of the reports must be advocated and strengthened. DNEA and the Khomas regional office should embark on tapping into available development in information technology by doing research into the possibility of disseminating the Examiners’ reports electronically. A pilot in this regard should be conducted in the Khomas region as a measure to ensure dissemination can become more efficient in the future. To ensure that teachers optimally utilize the Examiners’ reports, they should be provided to schools when the school first term commences. The Khomas regional office should strengthen their involvement in utilization by arranging annual workshops where the content of the reports can be discussed to ensure that the feedback given in the reports can aid in developing and strengthening Biology teachers’ subject content knowledge as well as pedagogical content knowledge. Optimal utilization of Examiners’ reports can enable mediation in learners which can ensure effective learning and mastery of Biology by learners which can ultimately lead to an improvement in pass rate in Biology. Therefore, appropriate support to aid teachers’ professional development can enhance maximum utilization. Furthermore, an area for future research could be to give the Examiners’ reports to learners to determine the impact it has on their learning.
- Full Text:
Exploring lecturer experiences of the use of ICT in blended learning : a case study at a South African university
- Authors: Ntlabathi, Siyanda
- Date: 2015
- Subjects: Blended learning -- South Africa , Information technology -- South Africa , Education, Higher -- Technological innovations , Computer-assisted instruction -- South Africa , Internet in education -- South Africa , Educational technology -- South Africa , Critical realism
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2044 , http://hdl.handle.net/10962/d1017355
- Description: ICTs have had a tremendous impact on our educational environment. There have been a huge number of developments and support in implementation of ICT in Higher Education teaching and learning, also referred to as e-learning. Similarly there appears to be quite a number of research conducted on the use of ICTs in blended learning settings worldwide and as well as in South Africa. Very little research however, has focussed on the experiences of lecturers with e-learning, specifically as it relates to Learning Management Systems (LMS). In trying to meet the requirements of its academic programmes and be in line with new developments worldwide, the University which is the focus of this study pilot projected the use of an LMS in a blended learning approach which integrates face-to-face classes with Blackboard, an ICT-based system or tool. Following the implementation of the pilot project, this study explores the experiences of lecturers in their blended learning environments at this university in the Eastern Cape province of South Africa. The research design was that of an interpretative paradigm within a qualitative research approach in a case study methodology. Purposive sampling of six lecturers from departments within faculties across two campuses was done. The data was gathered through interviews, a follow-up questionnaire and document analysis was employed. Using Critical and Social Realism as meta-theories the study employed aspects of Activity Theory as substantive theory to understand particular experiences of blended learning environments and identify conditions which enable and constrain engagement in these environments so as to explore potential lessons to inform the kind of educational support which could be offered to facilitate uptake of the LMS.
- Full Text:
- Authors: Ntlabathi, Siyanda
- Date: 2015
- Subjects: Blended learning -- South Africa , Information technology -- South Africa , Education, Higher -- Technological innovations , Computer-assisted instruction -- South Africa , Internet in education -- South Africa , Educational technology -- South Africa , Critical realism
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2044 , http://hdl.handle.net/10962/d1017355
- Description: ICTs have had a tremendous impact on our educational environment. There have been a huge number of developments and support in implementation of ICT in Higher Education teaching and learning, also referred to as e-learning. Similarly there appears to be quite a number of research conducted on the use of ICTs in blended learning settings worldwide and as well as in South Africa. Very little research however, has focussed on the experiences of lecturers with e-learning, specifically as it relates to Learning Management Systems (LMS). In trying to meet the requirements of its academic programmes and be in line with new developments worldwide, the University which is the focus of this study pilot projected the use of an LMS in a blended learning approach which integrates face-to-face classes with Blackboard, an ICT-based system or tool. Following the implementation of the pilot project, this study explores the experiences of lecturers in their blended learning environments at this university in the Eastern Cape province of South Africa. The research design was that of an interpretative paradigm within a qualitative research approach in a case study methodology. Purposive sampling of six lecturers from departments within faculties across two campuses was done. The data was gathered through interviews, a follow-up questionnaire and document analysis was employed. Using Critical and Social Realism as meta-theories the study employed aspects of Activity Theory as substantive theory to understand particular experiences of blended learning environments and identify conditions which enable and constrain engagement in these environments so as to explore potential lessons to inform the kind of educational support which could be offered to facilitate uptake of the LMS.
- Full Text:
Exploring patterns of Facebook usage, social capital, loneliness and well-being among a diverse South African student sample:
- Young, Charles, Strelitz, Larry N
- Authors: Young, Charles , Strelitz, Larry N
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143705 , vital:38275 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: There has been much debate over whether the use of social network sites isolate people and truncate their relationships or alternatively, provide beneficial connections with others. This debate has been framed by a growing international literature which explores the triadic relationship between the intensity of use of Facebook to the maintenance of social capital and in turn the relationship between social capital and wellbeing and loneliness. A random list of 1168 Rhodes University students was drawn from the total student body and invited to participate in an online survey. In total, 491 students completed the survey (42% response rate). Hierarchical regression analyses demonstrate that intensity of Facebook usage adds a very small contribution to social capital, is very weakly associated with loneliness, and is not associated with wellbeing. Results contrast with international studies that fail to recognise the extent to which race and class cleavages impact on access to and use of social media.
- Full Text:
- Authors: Young, Charles , Strelitz, Larry N
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143705 , vital:38275 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: There has been much debate over whether the use of social network sites isolate people and truncate their relationships or alternatively, provide beneficial connections with others. This debate has been framed by a growing international literature which explores the triadic relationship between the intensity of use of Facebook to the maintenance of social capital and in turn the relationship between social capital and wellbeing and loneliness. A random list of 1168 Rhodes University students was drawn from the total student body and invited to participate in an online survey. In total, 491 students completed the survey (42% response rate). Hierarchical regression analyses demonstrate that intensity of Facebook usage adds a very small contribution to social capital, is very weakly associated with loneliness, and is not associated with wellbeing. Results contrast with international studies that fail to recognise the extent to which race and class cleavages impact on access to and use of social media.
- Full Text:
Exploring problematic experiences : an IPA study of 'Internet Addiction'
- Authors: Allie, Naaheeda
- Date: 2015
- Subjects: Internet addiction , Compulsive behavior , Security (Psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3256 , http://hdl.handle.net/10962/d1016395
- Description: In the past two decades, a considerable amount of research has been carried out on the phenomenon of excessive Internet use, variously termed Internet addiction, Internet dependency and problematic Internet use. Despite this, there is still little agreement as to what constitutes this phenomenon, whether it should be considered a clinical disorder or not and what leads to this excessive or maladaptive use. The terminology used in this study is that of Problematic Internet Use (PIU). Several theoretical models have been proposed in the understanding of PIU including personality models, operant conditioning models, social cognitive and cognitive behavioural models (Davis, 2001; LaRose, lin & Eastin, 2003; Young, 1999). A proposed gap in the literature is the lack of studies exploring participant experiences of problematic Internet use. It is for this reason that this study aimed at exploring the experiences of a small sample of individuals with self-identified problematic Internet use. The implications of this phenomenological data for the above-mentioned theoretical models were then reviewed. This study used an Interpretative Phenomenological Analysis (IPA) approach in exploring these aims. A sample of four participants was selected through purposive sampling techniques. Four major themes emerged from the analysis namely: Escapism, Social Insecurity and Validation, Perfectionism and Control. These experiences of participants were also explored in terms of the conceptual models reviewed in order to compare how closely they related to participant experiences. A strong inter-relationship was found between the four themes mentioned above. The Internet appeared to provide a sense of control and validation to these individuals while simultaneously rendering them unable to maintain control of their Internet usage in relation to this. This sense of control was experienced through an escape from negative emotions, offline obligations and at times a dissatisfactory position in reality. Of the four models reviewed, the Social Cognitive model proposed by LaRose et al. (2003) appeared to offer the most relevant understanding of PIU to participant experiences. The presence of maladaptive cognitions also appeared to feature strongly as an underlying factor in participants' PIU, as theorised by cognitive behavioural models (Davis, 2001; Young, 1999) Finally recommendations are made for further more detailed exploration of PIU using interpretative, experiential methods.
- Full Text:
- Authors: Allie, Naaheeda
- Date: 2015
- Subjects: Internet addiction , Compulsive behavior , Security (Psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3256 , http://hdl.handle.net/10962/d1016395
- Description: In the past two decades, a considerable amount of research has been carried out on the phenomenon of excessive Internet use, variously termed Internet addiction, Internet dependency and problematic Internet use. Despite this, there is still little agreement as to what constitutes this phenomenon, whether it should be considered a clinical disorder or not and what leads to this excessive or maladaptive use. The terminology used in this study is that of Problematic Internet Use (PIU). Several theoretical models have been proposed in the understanding of PIU including personality models, operant conditioning models, social cognitive and cognitive behavioural models (Davis, 2001; LaRose, lin & Eastin, 2003; Young, 1999). A proposed gap in the literature is the lack of studies exploring participant experiences of problematic Internet use. It is for this reason that this study aimed at exploring the experiences of a small sample of individuals with self-identified problematic Internet use. The implications of this phenomenological data for the above-mentioned theoretical models were then reviewed. This study used an Interpretative Phenomenological Analysis (IPA) approach in exploring these aims. A sample of four participants was selected through purposive sampling techniques. Four major themes emerged from the analysis namely: Escapism, Social Insecurity and Validation, Perfectionism and Control. These experiences of participants were also explored in terms of the conceptual models reviewed in order to compare how closely they related to participant experiences. A strong inter-relationship was found between the four themes mentioned above. The Internet appeared to provide a sense of control and validation to these individuals while simultaneously rendering them unable to maintain control of their Internet usage in relation to this. This sense of control was experienced through an escape from negative emotions, offline obligations and at times a dissatisfactory position in reality. Of the four models reviewed, the Social Cognitive model proposed by LaRose et al. (2003) appeared to offer the most relevant understanding of PIU to participant experiences. The presence of maladaptive cognitions also appeared to feature strongly as an underlying factor in participants' PIU, as theorised by cognitive behavioural models (Davis, 2001; Young, 1999) Finally recommendations are made for further more detailed exploration of PIU using interpretative, experiential methods.
- Full Text:
Exploring the development of an integrated, participative, water quality management process for the Crocodile River catchment, focusing on the sugar industry
- Authors: Sahula, Asiphe
- Date: 2015
- Subjects: Water quality management -- South Africa -- Krokodilrivier (Mpumalanga) , Watersheds -- South Africa -- Krokodilrivier (Mpumalanga) , Integrated water development -- South Africa -- Krokodilrivier (Mpumalanga) , Water quality management -- Social aspects -- South Africa -- Krokodilrivier (Mpumalanga) , Social responsibility of business -- South Africa -- Krokodilrivier (Mpumalanga) , Water quality -- South Africa -- Krokodilrivier (Mpumalanga)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:6051 , http://hdl.handle.net/10962/d1017876
- Description: Water quality deterioration is reaching crisis proportions in South Africa. Many South African catchments are over-allocated, and decreasing volumes of source water mean increasing concentrations of pollutants. The Crocodile River Catchment in the Mpumalanga province in South Africa was identified through previous research, as a catchment faced with deteriorating source water quality for water users in the catchment. Poor source water quality has become a sufficiently acute concern for the stakeholders in this catchment to co-operate in developing a process that assists with compliance control of their water use and waste disposal to reduce costs, decrease industrial risks as water quality compliance increases, and improve source water quality. The sugar industry is downstream within the Crocodile River Catchment, and is affected by the activities of all upstream water users; the industry is thus dependent on the stakeholders upstream participating in the effective management of the resource. However, the sugar industry is also located just before the confluence of the Crocodile River and Komati River upstream of the Mozambique border, and thus the water quality of the sugar industry effluent will affect the quality of the water that flows into Mozambique. The sugar industry is on the opposite river bank to the Kruger National Park, which has high water resource protection goals. Therefore, the sugar industry has a national role to play in the management of water resources in the Crocodile River Catchment. This study provides a focused view of the role of the sugar industry in the development of a co-operative, integrated water quality management process (IWQMP) in the Crocodile River Catchment. In order to address the objectives of this study, this research drew from an understanding of the social processes that influence water management practices within the sugar industry as well as social processes that influence the role of the Inkomati-Usuthu Catchment Management Agency as the main governing institution in water resource management in the Inkomati Water Management Area. The study also drew from an understanding of scientific knowledge in terms of a water chemistry which describes the upstream and downstream water quality impacts related to the sugar industry. The water quality analysis for the Lower Crocodile River Catchment shows a decline in water quality in terms of Total Dissolved Solids (TDS) loads when moving from below Mbombela to the Mozambique border. The major sources of TDS in the Lower Crocodile River are point source dominated, which may be attributed to the extensive mining, industrial and municipal activities that occur across the catchment. When observing Total Alkalinity (TAL) and pH values from below Mbombela to the furthest monitoring point, there is deterioration in the quality of the water in the Lower Crocodile River, with the Kaap River contributing a negative effect that is diluted by the Crocodile main stem. The Hectorspruit Waste Water Treatment Works (WWTWs) (located in the Lower Crocodile River Catchment) contributes high concentrations of TDS and TAL into the Crocodile River. Total Inorganic Nitrogen and Soluble Reactive Phosphorus concentrations decrease in the lower reaches of the Crocodile River compared with the river below Mbombela, which can be attributed to the extensive sugar cane plantations located in the Lower Crocodile River Catchment acting as an “agricultural wetland” that serves a function of bioremediation resulting in large scale absorption of nutrients. This is an interesting result as earlier assumptions were that fertiliser application would result in an overall increase in nutrient loads and concentrations. Biomonitoring data show no substantial change in aquatic health in the LowerCrocodile River Catchment. For a catchment that has an extensive agricultural land use in terms of sugarcane and citrus production, the Crocodile River is unexpectedly not in a toxic state in terms of aquatic health. This is a positive result and it suggests that pesticide use is strictly controlled in the sugar and citrus industry in the Crocodile River Catchment. For long term sustainability, it is essential for the sugar industry to maintain (and possibly improve) this pesticide management. The social component of this study aimed to provide an analysis of the management practices of the sugar mill as well as examining agricultural practices in the sugar cane fields in relation to water quality management through the use of Cultural Historical Activity System Theory (CHAT). This component showed that there are contradictions within the sugar industry activity system that are considered to be areas of “tension” that can be loosened or focused on to improve the contribution the sugar industry can make to the IWQMP. Surfacing contradictions within the sugar industry activity system and the Inkomati-Usuthu Catchment Management Agency activity systems highlighted areas of potential for learning and change. While an understanding of biophysical processes through scientific knowledge is critical in water management decision making, it is evident that an understanding of other actors, institutions and networks that inform water quality management decision-making also plays a significant role. The notion of improving the role of scientific or biophysical knowledge in contributing to socio-ecologically robust knowledge co-creation, decisions and actions towards resolving water quality problems is emphasised. Specifically, moving towards improving interactions between scientists and other actors (water users in the Crocodile Catchment in this case), so that scientific practices become more orientated towards societal platforms where water quality management is tackled to enable improved water quality management practices. Therefore, linking the social and biophysical components in this study provides a holistic understanding of how the sugar industry can contribute to the development of an IWQMP for the Crocodile River catchment.
- Full Text:
- Authors: Sahula, Asiphe
- Date: 2015
- Subjects: Water quality management -- South Africa -- Krokodilrivier (Mpumalanga) , Watersheds -- South Africa -- Krokodilrivier (Mpumalanga) , Integrated water development -- South Africa -- Krokodilrivier (Mpumalanga) , Water quality management -- Social aspects -- South Africa -- Krokodilrivier (Mpumalanga) , Social responsibility of business -- South Africa -- Krokodilrivier (Mpumalanga) , Water quality -- South Africa -- Krokodilrivier (Mpumalanga)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:6051 , http://hdl.handle.net/10962/d1017876
- Description: Water quality deterioration is reaching crisis proportions in South Africa. Many South African catchments are over-allocated, and decreasing volumes of source water mean increasing concentrations of pollutants. The Crocodile River Catchment in the Mpumalanga province in South Africa was identified through previous research, as a catchment faced with deteriorating source water quality for water users in the catchment. Poor source water quality has become a sufficiently acute concern for the stakeholders in this catchment to co-operate in developing a process that assists with compliance control of their water use and waste disposal to reduce costs, decrease industrial risks as water quality compliance increases, and improve source water quality. The sugar industry is downstream within the Crocodile River Catchment, and is affected by the activities of all upstream water users; the industry is thus dependent on the stakeholders upstream participating in the effective management of the resource. However, the sugar industry is also located just before the confluence of the Crocodile River and Komati River upstream of the Mozambique border, and thus the water quality of the sugar industry effluent will affect the quality of the water that flows into Mozambique. The sugar industry is on the opposite river bank to the Kruger National Park, which has high water resource protection goals. Therefore, the sugar industry has a national role to play in the management of water resources in the Crocodile River Catchment. This study provides a focused view of the role of the sugar industry in the development of a co-operative, integrated water quality management process (IWQMP) in the Crocodile River Catchment. In order to address the objectives of this study, this research drew from an understanding of the social processes that influence water management practices within the sugar industry as well as social processes that influence the role of the Inkomati-Usuthu Catchment Management Agency as the main governing institution in water resource management in the Inkomati Water Management Area. The study also drew from an understanding of scientific knowledge in terms of a water chemistry which describes the upstream and downstream water quality impacts related to the sugar industry. The water quality analysis for the Lower Crocodile River Catchment shows a decline in water quality in terms of Total Dissolved Solids (TDS) loads when moving from below Mbombela to the Mozambique border. The major sources of TDS in the Lower Crocodile River are point source dominated, which may be attributed to the extensive mining, industrial and municipal activities that occur across the catchment. When observing Total Alkalinity (TAL) and pH values from below Mbombela to the furthest monitoring point, there is deterioration in the quality of the water in the Lower Crocodile River, with the Kaap River contributing a negative effect that is diluted by the Crocodile main stem. The Hectorspruit Waste Water Treatment Works (WWTWs) (located in the Lower Crocodile River Catchment) contributes high concentrations of TDS and TAL into the Crocodile River. Total Inorganic Nitrogen and Soluble Reactive Phosphorus concentrations decrease in the lower reaches of the Crocodile River compared with the river below Mbombela, which can be attributed to the extensive sugar cane plantations located in the Lower Crocodile River Catchment acting as an “agricultural wetland” that serves a function of bioremediation resulting in large scale absorption of nutrients. This is an interesting result as earlier assumptions were that fertiliser application would result in an overall increase in nutrient loads and concentrations. Biomonitoring data show no substantial change in aquatic health in the LowerCrocodile River Catchment. For a catchment that has an extensive agricultural land use in terms of sugarcane and citrus production, the Crocodile River is unexpectedly not in a toxic state in terms of aquatic health. This is a positive result and it suggests that pesticide use is strictly controlled in the sugar and citrus industry in the Crocodile River Catchment. For long term sustainability, it is essential for the sugar industry to maintain (and possibly improve) this pesticide management. The social component of this study aimed to provide an analysis of the management practices of the sugar mill as well as examining agricultural practices in the sugar cane fields in relation to water quality management through the use of Cultural Historical Activity System Theory (CHAT). This component showed that there are contradictions within the sugar industry activity system that are considered to be areas of “tension” that can be loosened or focused on to improve the contribution the sugar industry can make to the IWQMP. Surfacing contradictions within the sugar industry activity system and the Inkomati-Usuthu Catchment Management Agency activity systems highlighted areas of potential for learning and change. While an understanding of biophysical processes through scientific knowledge is critical in water management decision making, it is evident that an understanding of other actors, institutions and networks that inform water quality management decision-making also plays a significant role. The notion of improving the role of scientific or biophysical knowledge in contributing to socio-ecologically robust knowledge co-creation, decisions and actions towards resolving water quality problems is emphasised. Specifically, moving towards improving interactions between scientists and other actors (water users in the Crocodile Catchment in this case), so that scientific practices become more orientated towards societal platforms where water quality management is tackled to enable improved water quality management practices. Therefore, linking the social and biophysical components in this study provides a holistic understanding of how the sugar industry can contribute to the development of an IWQMP for the Crocodile River catchment.
- Full Text:
Exploring the emancipatory potential of nursing practice in relation to sexuality: a systematic literature review of nursing research 2009-2014
- Nhamo-Murire, Mercy, Macleod, Catriona I
- Authors: Nhamo-Murire, Mercy , Macleod, Catriona I
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143650 , vital:38270 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: Nurses play an important role in disseminating health information and in the provision of counselling concerning sexuality healthcare settings. There is some evidence, however, that nurses do not always consider issues relating to sexualities in their general practice, and when they do, may feel some discomfort in addressing sexuality. In this paper we report on a systematic review of research on nursing practice in relation to sexualities that appeared in nursing journals in the Web of Science database from 2009-2014. Thirty nine articles, which were published in English and reported on nursing practice in relation to sexualities, were thematically analysed. We focus on what research has been done and how this research may be used in the development of emancipatory nursing practice in relation to sexualities. Despite increasing attention being paid to social justice issues in nursing, the implications of this for nursing practice needs further exploration.
- Full Text:
- Authors: Nhamo-Murire, Mercy , Macleod, Catriona I
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143650 , vital:38270 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: Nurses play an important role in disseminating health information and in the provision of counselling concerning sexuality healthcare settings. There is some evidence, however, that nurses do not always consider issues relating to sexualities in their general practice, and when they do, may feel some discomfort in addressing sexuality. In this paper we report on a systematic review of research on nursing practice in relation to sexualities that appeared in nursing journals in the Web of Science database from 2009-2014. Thirty nine articles, which were published in English and reported on nursing practice in relation to sexualities, were thematically analysed. We focus on what research has been done and how this research may be used in the development of emancipatory nursing practice in relation to sexualities. Despite increasing attention being paid to social justice issues in nursing, the implications of this for nursing practice needs further exploration.
- Full Text:
Exploring the relationship between an "English-only" language-in-education policy and bilingual practices in secondary schools in Zanzibar
- Authors: Maalim, Haroun Ayoub
- Date: 2015
- Subjects: Language and education -- Zanzibar , Native language and education -- Zanzibar , Code switching (Linguistics) -- Zanzibar , Language policy -- Zanzibar
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3650 , http://hdl.handle.net/10962/d1017891
- Description: This thesis reports on the relationship between an English-only language-ineducation policy and bilingual practices in secondary schools in Zanzibar. The focus is on language use in the classroom against the backdrop of a top-down and English-only language-in-education policy. The main purpose has been to gain an in-depth understanding of the relationship between the stipulations of the policy which was imposed from above and the judicious bilingual practices which are a commonly accepted as the norm in secondary schools in Zanzibar. The study employed a mixed method approach (QUAL+quant) and embraced elements of ethnography. The data for this study was gathered from two secondary schools which were purposively selected on the basis of parameters that were set in this study. Among other things, these include the secondary schools which have both ‘Ordinary level’ and ‘Advance level’, and the schools which teach the same subject using Kiswahili as the language of learning and teaching at one level, and English as the language of learning and teaching at another level. Data were obtained from multiple sources. On the one hand, through ethnography, classroom observations, semi-structured interviews and focus group discussions with teachers and students, and interviews with key actors were conducted. On the other hand, students’ test scripts, and students’ test and examination results (scores) were analysed. Both purposive and random sampling were used to get the participants. Drawing from Ruiz’s (1984) seminal tripartite orientations of language planning (language as right, language as problem, and language as resource) thematic analysis, content analysis, and the Statistical Package for the Social Sciences (SPSS) were used to analyse data. The findings reveal that the use of bilingual (English and Kiswahili) in English medium subjects is a resource rather than a deficit since an overwhelming majority of students and some teachers cannot function positively in the topdown English-only language-in-education policy. Most significantly, teachers use Kiswahili in English medium subjects as a strategy for teaching terminologies, abstract concepts, and unfamiliar topics, as well as for clarification of ideas and for comprehension check. The study further indicates that the examinations and tests of English medium subjects do not assess what is exactly intended to be assessed (subject matter), but instead they assess English language. In addition, empirical evidence shows that language is a factor for students’ achievements in that students performed considerably better when the subjects were assessed in Kiswahili compared to the same subjects assessed in English. The findings further reveal that Kiswahili is suitable to be used as a sole language of learning and teaching in secondary schools of Zanzibar. Based on these findings, the study recommends that the use of Kiswahili in English medium subjects should be officially recognised and students should be given options of the language of assessment as an urgent step. Furthermore, given the urgency of the need for improving students’ performance, it is now high time to introduce Kiswahili medium of instruction secondary schools in Zanzibar which should co-exist with English medium of instruction secondary schools.
- Full Text:
- Authors: Maalim, Haroun Ayoub
- Date: 2015
- Subjects: Language and education -- Zanzibar , Native language and education -- Zanzibar , Code switching (Linguistics) -- Zanzibar , Language policy -- Zanzibar
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3650 , http://hdl.handle.net/10962/d1017891
- Description: This thesis reports on the relationship between an English-only language-ineducation policy and bilingual practices in secondary schools in Zanzibar. The focus is on language use in the classroom against the backdrop of a top-down and English-only language-in-education policy. The main purpose has been to gain an in-depth understanding of the relationship between the stipulations of the policy which was imposed from above and the judicious bilingual practices which are a commonly accepted as the norm in secondary schools in Zanzibar. The study employed a mixed method approach (QUAL+quant) and embraced elements of ethnography. The data for this study was gathered from two secondary schools which were purposively selected on the basis of parameters that were set in this study. Among other things, these include the secondary schools which have both ‘Ordinary level’ and ‘Advance level’, and the schools which teach the same subject using Kiswahili as the language of learning and teaching at one level, and English as the language of learning and teaching at another level. Data were obtained from multiple sources. On the one hand, through ethnography, classroom observations, semi-structured interviews and focus group discussions with teachers and students, and interviews with key actors were conducted. On the other hand, students’ test scripts, and students’ test and examination results (scores) were analysed. Both purposive and random sampling were used to get the participants. Drawing from Ruiz’s (1984) seminal tripartite orientations of language planning (language as right, language as problem, and language as resource) thematic analysis, content analysis, and the Statistical Package for the Social Sciences (SPSS) were used to analyse data. The findings reveal that the use of bilingual (English and Kiswahili) in English medium subjects is a resource rather than a deficit since an overwhelming majority of students and some teachers cannot function positively in the topdown English-only language-in-education policy. Most significantly, teachers use Kiswahili in English medium subjects as a strategy for teaching terminologies, abstract concepts, and unfamiliar topics, as well as for clarification of ideas and for comprehension check. The study further indicates that the examinations and tests of English medium subjects do not assess what is exactly intended to be assessed (subject matter), but instead they assess English language. In addition, empirical evidence shows that language is a factor for students’ achievements in that students performed considerably better when the subjects were assessed in Kiswahili compared to the same subjects assessed in English. The findings further reveal that Kiswahili is suitable to be used as a sole language of learning and teaching in secondary schools of Zanzibar. Based on these findings, the study recommends that the use of Kiswahili in English medium subjects should be officially recognised and students should be given options of the language of assessment as an urgent step. Furthermore, given the urgency of the need for improving students’ performance, it is now high time to introduce Kiswahili medium of instruction secondary schools in Zanzibar which should co-exist with English medium of instruction secondary schools.
- Full Text:
Exploring the uses of mental skills by competitive road running athletes
- Ngobese, Khayelihle Mbongeleni Emmanuel
- Authors: Ngobese, Khayelihle Mbongeleni Emmanuel
- Date: 2015
- Subjects: Long-distance runners -- Psychology , Long-distance running -- Psychological aspects , Competition (Psychology) , Long-distance running -- Training , Marathon running -- Psychological aspects , Goal (Psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3268 , http://hdl.handle.net/10962/d1020310
- Description: Research on athletes has shown that mental skills are an important component of being a successful athlete. The importance of these mental skills is seen in the number of athletes who have formally started training using mental skills training programmes (MST) according to the literature. The study of mental skills in South Africa lags behind other countries like USA, UK and Sweden. This particular study explored the use of mental skills by road running athletes. The study was conducted with six competitive marathon athletes. Semi-structured interviews were conducted as part of an elaborate qualitative methodology design. The data collected from these semi-structured interviews was analysed using thematic analysis. The results show that road running athletes use mental skills that include; mental rehearsal, planning, goal setting and self-talk. The athletes in this research showed the importance of mental skills and it is recommended that formal training in these mental skills will be highly beneficial not only to road running athletes but for all South African sports people in general
- Full Text:
- Authors: Ngobese, Khayelihle Mbongeleni Emmanuel
- Date: 2015
- Subjects: Long-distance runners -- Psychology , Long-distance running -- Psychological aspects , Competition (Psychology) , Long-distance running -- Training , Marathon running -- Psychological aspects , Goal (Psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3268 , http://hdl.handle.net/10962/d1020310
- Description: Research on athletes has shown that mental skills are an important component of being a successful athlete. The importance of these mental skills is seen in the number of athletes who have formally started training using mental skills training programmes (MST) according to the literature. The study of mental skills in South Africa lags behind other countries like USA, UK and Sweden. This particular study explored the use of mental skills by road running athletes. The study was conducted with six competitive marathon athletes. Semi-structured interviews were conducted as part of an elaborate qualitative methodology design. The data collected from these semi-structured interviews was analysed using thematic analysis. The results show that road running athletes use mental skills that include; mental rehearsal, planning, goal setting and self-talk. The athletes in this research showed the importance of mental skills and it is recommended that formal training in these mental skills will be highly beneficial not only to road running athletes but for all South African sports people in general
- Full Text:
Facile synthesis, spectroscopic and electrochemical properties, and theoretical calculations of porphyrin dimers with a bridging amide-bonded xanthene moiety
- Liang, Xu, Xu, Li, Li, Minzhi, Mack, John, Stone, Justin, Nyokong, Tebello, Jiang, Yu, Kobayashi, Nagao, Zhu, Weihua
- Authors: Liang, Xu , Xu, Li , Li, Minzhi , Mack, John , Stone, Justin , Nyokong, Tebello , Jiang, Yu , Kobayashi, Nagao , Zhu, Weihua
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241390 , vital:50935 , xlink:href="https://doi.org/10.1142/S1088424615500492"
- Description: A free base porphyrin dimer bridged by a flexible amide-bonded xanthene moiety and its binuclear zinc(II) complex zinc(II) complex were synthesized and characterized. Structural characterization by MS and 1H NMR spectroscopy confirmed the bridged porphyrin dimer structure. The properties of the dimers were characterized by IR, UV-visible absorption, fluorescence and magnetic circular dichroism (MCD) spectroscopy, and electrochemistry studies. Theoretical calculations were carried out to analyze the electronic structures of porphyrin dimers with a bridging amide-bonded xanthene moiety.
- Full Text:
- Authors: Liang, Xu , Xu, Li , Li, Minzhi , Mack, John , Stone, Justin , Nyokong, Tebello , Jiang, Yu , Kobayashi, Nagao , Zhu, Weihua
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241390 , vital:50935 , xlink:href="https://doi.org/10.1142/S1088424615500492"
- Description: A free base porphyrin dimer bridged by a flexible amide-bonded xanthene moiety and its binuclear zinc(II) complex zinc(II) complex were synthesized and characterized. Structural characterization by MS and 1H NMR spectroscopy confirmed the bridged porphyrin dimer structure. The properties of the dimers were characterized by IR, UV-visible absorption, fluorescence and magnetic circular dichroism (MCD) spectroscopy, and electrochemistry studies. Theoretical calculations were carried out to analyze the electronic structures of porphyrin dimers with a bridging amide-bonded xanthene moiety.
- Full Text:
Feeding ecology, residency patterns and migration dynamics of bull sharks (Carcharhinus leucas) in the southwest Indian Ocean
- Authors: Daly, Ryan
- Date: 2015
- Subjects: Bull shark -- Ecology , Bull shark -- Feeding and feeds
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5924 , http://hdl.handle.net/10962/d1017802
- Description: Bull sharks (Carcharhinus leucas) are globally distributed top predators that play an important ecological role within coastal marine communities. However, little is known about how the spatial and temporal scales of their habitat use are associated with their ecological role. In this study, a population of sub-adult and adult bull sharks were investigated within a remote subtropical marine community in the southwest Indian Ocean off the coast of southern Mozambique. The main objectives of the study were to test a minimally invasive remote biopsy sampling method; to investigate the feeding ecology of bull sharks; and to investigate the temporal and spatial scales of bull shark residency patterns and migration dynamics. Biopsy tests on free-swimming bull sharks showed that the devised sampling technique provided a minimally invasive and consistent method (biopsy retention rate = 87%) to obtain muscle tissue samples sufficiently large enough (310±78mg, mean ± SD) for stable isotope analysis. Results from the stable isotope analysis showed that adult bull sharks appeared to exhibit a shift towards consistentlyhigher trophic level prey from an expanded foraging range compared to sub-adults, possibly due to increased mobility linked with size. Additionally, bull sharks had significantly broader niche widths compared to top predatory teleost assemblages with a wide and enriched range of δ13C values relative to the local marine community, suggesting that they forage over broad spatial scales along the east coast of southern Africa. Results from the passive acoustic telemetry investigation, conducted over a period between 10 and 22 months, supported these findings showing that the majority of tagged adult sharksexhibited temporally and spatially variable residency patterns interspersed with migration events. Ten individuals undertook coastal migrations that ranged between 433 and 709km (mean = 533km) with eight of these sharks returning to the study site. During migration, individuals exhibited rates of movement between 2 and 59km.d-1 (mean = 17.58km.d-1) and were recorded travelling annual distances of between 450 and 3760km (mean = 1163km). These findings suggest that adult bull sharks are not the sedentary species once thought to be but rather, consistently move over broad spatial scales on the east coast of southern Africa and play an important predatory role shaping and linking ecological processes within the southwest Indian Ocean.
- Full Text:
- Authors: Daly, Ryan
- Date: 2015
- Subjects: Bull shark -- Ecology , Bull shark -- Feeding and feeds
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5924 , http://hdl.handle.net/10962/d1017802
- Description: Bull sharks (Carcharhinus leucas) are globally distributed top predators that play an important ecological role within coastal marine communities. However, little is known about how the spatial and temporal scales of their habitat use are associated with their ecological role. In this study, a population of sub-adult and adult bull sharks were investigated within a remote subtropical marine community in the southwest Indian Ocean off the coast of southern Mozambique. The main objectives of the study were to test a minimally invasive remote biopsy sampling method; to investigate the feeding ecology of bull sharks; and to investigate the temporal and spatial scales of bull shark residency patterns and migration dynamics. Biopsy tests on free-swimming bull sharks showed that the devised sampling technique provided a minimally invasive and consistent method (biopsy retention rate = 87%) to obtain muscle tissue samples sufficiently large enough (310±78mg, mean ± SD) for stable isotope analysis. Results from the stable isotope analysis showed that adult bull sharks appeared to exhibit a shift towards consistentlyhigher trophic level prey from an expanded foraging range compared to sub-adults, possibly due to increased mobility linked with size. Additionally, bull sharks had significantly broader niche widths compared to top predatory teleost assemblages with a wide and enriched range of δ13C values relative to the local marine community, suggesting that they forage over broad spatial scales along the east coast of southern Africa. Results from the passive acoustic telemetry investigation, conducted over a period between 10 and 22 months, supported these findings showing that the majority of tagged adult sharksexhibited temporally and spatially variable residency patterns interspersed with migration events. Ten individuals undertook coastal migrations that ranged between 433 and 709km (mean = 533km) with eight of these sharks returning to the study site. During migration, individuals exhibited rates of movement between 2 and 59km.d-1 (mean = 17.58km.d-1) and were recorded travelling annual distances of between 450 and 3760km (mean = 1163km). These findings suggest that adult bull sharks are not the sedentary species once thought to be but rather, consistently move over broad spatial scales on the east coast of southern Africa and play an important predatory role shaping and linking ecological processes within the southwest Indian Ocean.
- Full Text:
Female identity in the post-millennial Nigerian novel: a study of Adichie, Atta, and Unigwe
- Authors: Wambui, Mary Theru
- Date: 2015
- Subjects: Adichie, Chimamanda Ngozi, 1977- -- Criticism and interpretation , Adichie, Chimamanda Ngozi, 1977-. Purple hibiscus , Atta, Sefi -- Criticism and interpretation , Atta, Sefi -- Everything good will come , Unigwe, Chika. Criticism and interpretation , Unigwe, Chika. Fata Morgana -- English , Nigerian fiction -- History and criticism , Women -- Identity , Women in literature , Feminism in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2330 , http://hdl.handle.net/10962/d1020013
- Description: This thesis project examines the work of three female Nigerian authors: Chimamanda Ngozi Adichie, Sefi Atta and Chika Unigwe. They are part of a growing number of young African writers who are receiving international acclaim and challenging narratives that have long defined the continent in pejorative terms. They question what it means to be female and African in a transcultural, global world but counter discourses that are both restrictive and prescriptive. Their female characters are not imaged in binary terms as either victims or villains. For all three writers, the African story has to be told in its entirety incorporating what some may argue are negative stereotypes but doing so in a manner that examines and undermines those same stereotypes. For the purposes of the thesis, I focus on their first novels: Adichie’s Purple Hibiscus, Atta’s Everything Good Will Come and Unigwe’s On Black Sisters’ Street. Chapter One examines Purple Hibiscus and argues that the novel is much more than a coming of age story or, as some critics have posited, an allegory of the postcolonial state. Chapter Two highlights Atta’s use of fairly familiar feminist theories but grounds them in the lived realities of the African city. All three authors are concerned with issues of violence and death. Unigwe’s novel, which forms the focus of Chapter Three, offers a critical perspective on how both of those themes intersect with the increasing commercialisation of global culture. Her characters are female sex workers whose lives are irrevocably altered by the murder of one of their colleagues. I conclude by arguing that the three novels offer a nuanced if not necessarily new understanding of the various social, economic and political forces that continue to shape the lives of women on the continent.
- Full Text:
- Authors: Wambui, Mary Theru
- Date: 2015
- Subjects: Adichie, Chimamanda Ngozi, 1977- -- Criticism and interpretation , Adichie, Chimamanda Ngozi, 1977-. Purple hibiscus , Atta, Sefi -- Criticism and interpretation , Atta, Sefi -- Everything good will come , Unigwe, Chika. Criticism and interpretation , Unigwe, Chika. Fata Morgana -- English , Nigerian fiction -- History and criticism , Women -- Identity , Women in literature , Feminism in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2330 , http://hdl.handle.net/10962/d1020013
- Description: This thesis project examines the work of three female Nigerian authors: Chimamanda Ngozi Adichie, Sefi Atta and Chika Unigwe. They are part of a growing number of young African writers who are receiving international acclaim and challenging narratives that have long defined the continent in pejorative terms. They question what it means to be female and African in a transcultural, global world but counter discourses that are both restrictive and prescriptive. Their female characters are not imaged in binary terms as either victims or villains. For all three writers, the African story has to be told in its entirety incorporating what some may argue are negative stereotypes but doing so in a manner that examines and undermines those same stereotypes. For the purposes of the thesis, I focus on their first novels: Adichie’s Purple Hibiscus, Atta’s Everything Good Will Come and Unigwe’s On Black Sisters’ Street. Chapter One examines Purple Hibiscus and argues that the novel is much more than a coming of age story or, as some critics have posited, an allegory of the postcolonial state. Chapter Two highlights Atta’s use of fairly familiar feminist theories but grounds them in the lived realities of the African city. All three authors are concerned with issues of violence and death. Unigwe’s novel, which forms the focus of Chapter Three, offers a critical perspective on how both of those themes intersect with the increasing commercialisation of global culture. Her characters are female sex workers whose lives are irrevocably altered by the murder of one of their colleagues. I conclude by arguing that the three novels offer a nuanced if not necessarily new understanding of the various social, economic and political forces that continue to shape the lives of women on the continent.
- Full Text:
Fire and water : a transdisciplinary investigation of water governance in the lower Sundays River Valley, South Africa
- Authors: Clifford-Holmes, Jai Kumar
- Date: 2015
- Subjects: Lower Sundays River Valley Municipality (Eastern Cape, South Africa) , Water -- Law and legislation -- South Africa , Water-supply -- Management , Municipal services -- South Africa -- Eastern Cape , Fire extinction -- South Africa -- Eastern Cape , Integrated water development -- South Africa -- Eastern Cape , Water quality management -- South Africa -- Eastern Cape , Water resources development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6047 , http://hdl.handle.net/10962/d1017870
- Description: The implementation of water policy and the integrated management of water face multiple challenges in South Africa (SA), despite the successes of post-apartheid government programmes in which some significant equity, sustainability and efficiency milestones have been met. This study uses a series of intervention processes into municipal water service delivery to explore the context, constraints, and real-world messiness in which local water authorities operate. The equitable provision of drinking water by local government and the collaborative management of untreated water by ‘water user associations’ are two sites of institutional conflict that have been subjected to broad ‘turnaround’ and ‘transformation’ attempts at the national level. This thesis seeks to explore and understand the use of transdisciplinary research in engaging local water authorities in a process of institutional change that increases the likelihood of equitable water supply in the Lower Sundays River Valley (LSRV). Fieldwork was conducted as part of a broader action research process involving the attempted ‘turnaround’ of the Sundays River Valley Municipality (SRVM) between 2011 and 2014. A multi-method research approach was employed, which drew on institutional, ethnographic, and systems analyses within an evolving, transdisciplinary methodology. In the single case study research design, qualitative and quantitative data were collected via participant observation, interviews and documentary sources. Analytical methods included system dynamics modelling and an adapted form of the ethnographic tool of ‘thick description’, which were linked in a governance analysis. Government interventions into the SRVM failed to take account of the systemic complexity of the municipal operating environment, the interactions of which are described in this study as the ‘modes of failure’ of local government. These modes included the perpetual ‘firefighting’ responses of municipal officials to crises, and the simultaneous underinvestment in, and over-extension of, water supply infrastructure, which is a rational approach to addressing current water shortages when funds are unavailable for maintenance, refurbishment, or the construction of new infrastructure. The over-burdening of municipalities with technocratic requirements, the presence of gaps in the institutional arrangements governing water supply in the LSRV, and the lack of coordination in government interventions are analysed in this study, with policy recommendations resulting. The primary contribution of this study is in providing a substantively-contextualised case study that illustrates the value of systemic, engaged, extended, and embedded transdisciplinary research.
- Full Text:
- Authors: Clifford-Holmes, Jai Kumar
- Date: 2015
- Subjects: Lower Sundays River Valley Municipality (Eastern Cape, South Africa) , Water -- Law and legislation -- South Africa , Water-supply -- Management , Municipal services -- South Africa -- Eastern Cape , Fire extinction -- South Africa -- Eastern Cape , Integrated water development -- South Africa -- Eastern Cape , Water quality management -- South Africa -- Eastern Cape , Water resources development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6047 , http://hdl.handle.net/10962/d1017870
- Description: The implementation of water policy and the integrated management of water face multiple challenges in South Africa (SA), despite the successes of post-apartheid government programmes in which some significant equity, sustainability and efficiency milestones have been met. This study uses a series of intervention processes into municipal water service delivery to explore the context, constraints, and real-world messiness in which local water authorities operate. The equitable provision of drinking water by local government and the collaborative management of untreated water by ‘water user associations’ are two sites of institutional conflict that have been subjected to broad ‘turnaround’ and ‘transformation’ attempts at the national level. This thesis seeks to explore and understand the use of transdisciplinary research in engaging local water authorities in a process of institutional change that increases the likelihood of equitable water supply in the Lower Sundays River Valley (LSRV). Fieldwork was conducted as part of a broader action research process involving the attempted ‘turnaround’ of the Sundays River Valley Municipality (SRVM) between 2011 and 2014. A multi-method research approach was employed, which drew on institutional, ethnographic, and systems analyses within an evolving, transdisciplinary methodology. In the single case study research design, qualitative and quantitative data were collected via participant observation, interviews and documentary sources. Analytical methods included system dynamics modelling and an adapted form of the ethnographic tool of ‘thick description’, which were linked in a governance analysis. Government interventions into the SRVM failed to take account of the systemic complexity of the municipal operating environment, the interactions of which are described in this study as the ‘modes of failure’ of local government. These modes included the perpetual ‘firefighting’ responses of municipal officials to crises, and the simultaneous underinvestment in, and over-extension of, water supply infrastructure, which is a rational approach to addressing current water shortages when funds are unavailable for maintenance, refurbishment, or the construction of new infrastructure. The over-burdening of municipalities with technocratic requirements, the presence of gaps in the institutional arrangements governing water supply in the LSRV, and the lack of coordination in government interventions are analysed in this study, with policy recommendations resulting. The primary contribution of this study is in providing a substantively-contextualised case study that illustrates the value of systemic, engaged, extended, and embedded transdisciplinary research.
- Full Text:
Fish utilization of surf-zones. Are they changing? A case study of the sheltered, warm-temperate King’s Beach
- Rishworth, Gavin M, Strydom, Nadine A, Potts, Warren M
- Authors: Rishworth, Gavin M , Strydom, Nadine A , Potts, Warren M
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124504 , vital:35619 , https://doi.org/10.1080/15627020.2014.11407616
- Description: Surf-zone fish communities and their shifts over time are generally poorly understood. The aim of this study was to compare the current surf-zone fish assemblage at King’s Beach, South Africa, to a similar study conducted three decades ago, before the collapse of many exploited shore fishes in the region. Beach seine nets (mesh sizes of 10 and 50 mm) were used to target juvenile and adult fishes bimonthly from February to August 2011 over the high tide around sunset. A total of 14 species were recorded in both the 30mand 100mseine nets. The catch in these seine nets was dominated by Pomadasys olivaceus and Liza richardsonii, and this was significantly different to three decades ago, when P. olivaceus, Sarpa salpa and Diplodus capensis dominated the catch. Important linefish species belonging to the Sparidae and Sciaenidae families were significantly smaller and less abundant in this study. Two sparids, S. salpa and Lithognathus mormyrus, which made a large contribution to the surf-zone catch three decades ago were absent during this study. Reasons for the significant shifts in the surf-zone fish community, including overexploitation of the linefish and potential habitat modification, are discussed.
- Full Text:
- Authors: Rishworth, Gavin M , Strydom, Nadine A , Potts, Warren M
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124504 , vital:35619 , https://doi.org/10.1080/15627020.2014.11407616
- Description: Surf-zone fish communities and their shifts over time are generally poorly understood. The aim of this study was to compare the current surf-zone fish assemblage at King’s Beach, South Africa, to a similar study conducted three decades ago, before the collapse of many exploited shore fishes in the region. Beach seine nets (mesh sizes of 10 and 50 mm) were used to target juvenile and adult fishes bimonthly from February to August 2011 over the high tide around sunset. A total of 14 species were recorded in both the 30mand 100mseine nets. The catch in these seine nets was dominated by Pomadasys olivaceus and Liza richardsonii, and this was significantly different to three decades ago, when P. olivaceus, Sarpa salpa and Diplodus capensis dominated the catch. Important linefish species belonging to the Sparidae and Sciaenidae families were significantly smaller and less abundant in this study. Two sparids, S. salpa and Lithognathus mormyrus, which made a large contribution to the surf-zone catch three decades ago were absent during this study. Reasons for the significant shifts in the surf-zone fish community, including overexploitation of the linefish and potential habitat modification, are discussed.
- Full Text:
Fluorescence behavior and singlet oxygen generating abilities of aluminum phthalocyanine in the presence of anisotropic gold nanoparticles
- Mthethwa, Thandekile, Nyokong, Tebello
- Authors: Mthethwa, Thandekile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193598 , vital:45351 , xlink:href="https://doi.org/10.1016/j.jlumin.2014.09.005"
- Description: Gold nanoparticles (spheres, rods and bipyramids) were synthesized. The nanocrystals were characterized by UV–visible spectrometry, transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The as prepared gold nanoparticles were then conjugated to a quaternized 2,(3)-tetra [2-(dimethylamino) ethanethio] substituted Al(OH) phthalocyanine (complex 1). The conjugation of phthalocyanines with gold nanoparticles resulted in a decrease in the fluorescence quantum yields and lifetimes. Conversely, an increase in the singlet oxygen quantum yields was observed for the conjugated complex 1 in the presence of AuNPs.
- Full Text:
- Authors: Mthethwa, Thandekile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193598 , vital:45351 , xlink:href="https://doi.org/10.1016/j.jlumin.2014.09.005"
- Description: Gold nanoparticles (spheres, rods and bipyramids) were synthesized. The nanocrystals were characterized by UV–visible spectrometry, transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The as prepared gold nanoparticles were then conjugated to a quaternized 2,(3)-tetra [2-(dimethylamino) ethanethio] substituted Al(OH) phthalocyanine (complex 1). The conjugation of phthalocyanines with gold nanoparticles resulted in a decrease in the fluorescence quantum yields and lifetimes. Conversely, an increase in the singlet oxygen quantum yields was observed for the conjugated complex 1 in the presence of AuNPs.
- Full Text:
Fluorescence behavior and singlet oxygen generating abilities of aluminum phthalocyanine in the presence of anisotropic gold nanoparticles
- Mthethwa, Thandekile, Nyokong, Tebello
- Authors: Mthethwa, Thandekile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189865 , vital:44941 , xlink:href="https://doi.org/10.1016/j.jlumin.2014.09.005"
- Description: Gold nanoparticles (spheres, rods and bipyramids) were synthesized. The nanocrystals were characterized by UV–visible spectrometry, transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The as prepared gold nanoparticles were then conjugated to a quaternized 2,(3)-tetra [2-(dimethylamino) ethanethio] substituted Al(OH) phthalocyanine (complex 1). The conjugation of phthalocyanines with gold nanoparticles resulted in a decrease in the fluorescence quantum yields and lifetimes. Conversely, an increase in the singlet oxygen quantum yields was observed for the conjugated complex 1 in the presence of AuNPs.
- Full Text:
- Authors: Mthethwa, Thandekile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189865 , vital:44941 , xlink:href="https://doi.org/10.1016/j.jlumin.2014.09.005"
- Description: Gold nanoparticles (spheres, rods and bipyramids) were synthesized. The nanocrystals were characterized by UV–visible spectrometry, transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The as prepared gold nanoparticles were then conjugated to a quaternized 2,(3)-tetra [2-(dimethylamino) ethanethio] substituted Al(OH) phthalocyanine (complex 1). The conjugation of phthalocyanines with gold nanoparticles resulted in a decrease in the fluorescence quantum yields and lifetimes. Conversely, an increase in the singlet oxygen quantum yields was observed for the conjugated complex 1 in the presence of AuNPs.
- Full Text:
Fluorescence Behaviour of an Aluminium Octacarboxy Phthalocyanine-NaYGdF 4
- Taylor, Jessica, Litwinski, Christian, Nyokong, Tebello, Antunes, Edith M
- Authors: Taylor, Jessica , Litwinski, Christian , Nyokong, Tebello , Antunes, Edith M
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189503 , vital:44852 , xlink:href="https://doi.org/10.1007/s10895-015-1539-8"
- Description: Using a methanol assisted thermal decomposition approach, sphere shaped NaYGdF4:Yb/Er upconversion nanoparticles (UCNPs) were successfully synthesized. The chemical, spectroscopic and fluorescence properties of the UCNPs were fully characterized. Characteristic upconversion fluorescence emissions were produced by the NPs in the green, red and NIR regions and the NPs were also shown to possess paramagnetic properties. The influence of the UCNPs on the spectroscopic and fluorescence properties of an aluminium octacarboxy phthalocyanine AlOCPc was investigated. Covalent conjugation to an AlOCPc resulted in a large blue shift of the phthalocyanine’s Q band, which was accompanied by a decrease in the Pc’s fluorescence lifetime in DMSO. By combining the phthalocyanine and upconversion nanoparticle, we present a system capable of multimodal imaging, using both the upconversion nanoparticle’s and phthalocyanine’s emission, and magnetic resonance imaging (as a result of doping the upconversion nanoparticles with Gd3+ ions).
- Full Text:
- Authors: Taylor, Jessica , Litwinski, Christian , Nyokong, Tebello , Antunes, Edith M
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189503 , vital:44852 , xlink:href="https://doi.org/10.1007/s10895-015-1539-8"
- Description: Using a methanol assisted thermal decomposition approach, sphere shaped NaYGdF4:Yb/Er upconversion nanoparticles (UCNPs) were successfully synthesized. The chemical, spectroscopic and fluorescence properties of the UCNPs were fully characterized. Characteristic upconversion fluorescence emissions were produced by the NPs in the green, red and NIR regions and the NPs were also shown to possess paramagnetic properties. The influence of the UCNPs on the spectroscopic and fluorescence properties of an aluminium octacarboxy phthalocyanine AlOCPc was investigated. Covalent conjugation to an AlOCPc resulted in a large blue shift of the phthalocyanine’s Q band, which was accompanied by a decrease in the Pc’s fluorescence lifetime in DMSO. By combining the phthalocyanine and upconversion nanoparticle, we present a system capable of multimodal imaging, using both the upconversion nanoparticle’s and phthalocyanine’s emission, and magnetic resonance imaging (as a result of doping the upconversion nanoparticles with Gd3+ ions).
- Full Text:
Food on the Table: Human Responses and Changing Coastal Fisheries in Solomon Islands
- Albert, Simon, Aswani, Shankar, Fisher, Paul L, Albert, Joelle
- Authors: Albert, Simon , Aswani, Shankar , Fisher, Paul L , Albert, Joelle
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/421887 , vital:71893 , xlink:href="https://doi.org/10.1371/journal.pone.0130800"
- Description: Globally the majority of commercial fisheries have experienced dramatic declines in stock and catch. Likewise, projections for many subsistence fisheries in the tropics indicate a dramatic decline is looming in the coming decades. In the Pacific Islands coastal fisheries provide basic subsistence needs for millions of people. A decline in fish catch would therefore have profound impacts on the health and livelihoods of these coastal communities. Given the decrease in local catch rates reported for many coastal communities in the Pacific, it is important to understand if fishers have responded to ecological change (either by expanding their fishing range and/or increasing their fishing effort), and if so, to evaluate the costs or benefits of these responses. We compare data from fish catches in 1995 and 2011 from a rural coastal community in Solomon Islands to examine the potentially changing coastal reef fishery at these time points. In particular we found changes in preferred fishing locations, fishing methodology and catch composition between these data sets. The results indicate that despite changes in catch rates (catch per unit effort) between data collected in 2011 and 16 years previously, the study community was able to increase gross catches through visiting fishing sites further away, diversifying fishing methods and targeting pelagic species through trolling. Such insight into local-scale responses to changing resources and/or fisheries development will help scientists and policy makers throughout the Pacific region in managing the region’s fisheries in the future.
- Full Text:
- Authors: Albert, Simon , Aswani, Shankar , Fisher, Paul L , Albert, Joelle
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/421887 , vital:71893 , xlink:href="https://doi.org/10.1371/journal.pone.0130800"
- Description: Globally the majority of commercial fisheries have experienced dramatic declines in stock and catch. Likewise, projections for many subsistence fisheries in the tropics indicate a dramatic decline is looming in the coming decades. In the Pacific Islands coastal fisheries provide basic subsistence needs for millions of people. A decline in fish catch would therefore have profound impacts on the health and livelihoods of these coastal communities. Given the decrease in local catch rates reported for many coastal communities in the Pacific, it is important to understand if fishers have responded to ecological change (either by expanding their fishing range and/or increasing their fishing effort), and if so, to evaluate the costs or benefits of these responses. We compare data from fish catches in 1995 and 2011 from a rural coastal community in Solomon Islands to examine the potentially changing coastal reef fishery at these time points. In particular we found changes in preferred fishing locations, fishing methodology and catch composition between these data sets. The results indicate that despite changes in catch rates (catch per unit effort) between data collected in 2011 and 16 years previously, the study community was able to increase gross catches through visiting fishing sites further away, diversifying fishing methods and targeting pelagic species through trolling. Such insight into local-scale responses to changing resources and/or fisheries development will help scientists and policy makers throughout the Pacific region in managing the region’s fisheries in the future.
- Full Text:
Formulating an IT governance framework
- Authors: Roos, Pieter
- Date: 2015
- Subjects: Corporate governance -- Information technology -- South Africa , Information technology -- Management
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1156 , http://hdl.handle.net/10962/d1017541
- Description: Modern organisations make substantial investments in Information Technology (IT). Corporate governance practices can no longer ignore the importance of effectively governing IT. Consequently, the third King Report on Corporate Governance (King III) makes specific provision for IT governance, which is implemented through the establishment of an IT governance framework. The purpose of this research is to develop a generic IT governance framework, suitable to any large South African organisation in the public or private sector. The literature considered for this research confirmed the extent of standards and practices available in support of IT governance, together with the roles and structures required to implement them. These included well-known publications such as COBIT, Prince2, ITIL and ISO/IEC27000. Based on the literature review, a theoretical Processes, Enablers and Structures (PES) IT Governance Framework was formulated. The framework was further explored by means of a survey of and structured interview with ten Chief Information Officers (CIOs) of South African organisations with a turnover in excess of R1bn per annum. The final PES IT Governance Framework comprises three dimensions, each of which contains a set of constituent components: • Processes: Strategic Alignment, Value Delivery, Resource Management, Risk Management and Performance Measurement. • Enablers: IT Sub Processes, Supporting Documentation, IT Control Framework, Technology Architecture, Desirable Practice, IT Portfolio Management and Regulation. • Structures: The Board, Office of the CIO, IT Steering Committee, Technology Architecture Forum, IT Programme Management Office and Information Security Organisation. As the number of regulatory requirements and associated compliance pressures grow, the importance of an effective IT governance framework also becomes more prominent. The PES IT Governance Framework offers a uniquely practical approach to addressing IT governance principles that are often regarded as abstract. The final PES IT Governance Framework provides clear guidance on how organisations could implement an IT governance framework, which addresses the strategic alignment of IT to business, value delivery by IT investments, IT risk management, IT resource management and IT performance measurement.
- Full Text:
- Authors: Roos, Pieter
- Date: 2015
- Subjects: Corporate governance -- Information technology -- South Africa , Information technology -- Management
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1156 , http://hdl.handle.net/10962/d1017541
- Description: Modern organisations make substantial investments in Information Technology (IT). Corporate governance practices can no longer ignore the importance of effectively governing IT. Consequently, the third King Report on Corporate Governance (King III) makes specific provision for IT governance, which is implemented through the establishment of an IT governance framework. The purpose of this research is to develop a generic IT governance framework, suitable to any large South African organisation in the public or private sector. The literature considered for this research confirmed the extent of standards and practices available in support of IT governance, together with the roles and structures required to implement them. These included well-known publications such as COBIT, Prince2, ITIL and ISO/IEC27000. Based on the literature review, a theoretical Processes, Enablers and Structures (PES) IT Governance Framework was formulated. The framework was further explored by means of a survey of and structured interview with ten Chief Information Officers (CIOs) of South African organisations with a turnover in excess of R1bn per annum. The final PES IT Governance Framework comprises three dimensions, each of which contains a set of constituent components: • Processes: Strategic Alignment, Value Delivery, Resource Management, Risk Management and Performance Measurement. • Enablers: IT Sub Processes, Supporting Documentation, IT Control Framework, Technology Architecture, Desirable Practice, IT Portfolio Management and Regulation. • Structures: The Board, Office of the CIO, IT Steering Committee, Technology Architecture Forum, IT Programme Management Office and Information Security Organisation. As the number of regulatory requirements and associated compliance pressures grow, the importance of an effective IT governance framework also becomes more prominent. The PES IT Governance Framework offers a uniquely practical approach to addressing IT governance principles that are often regarded as abstract. The final PES IT Governance Framework provides clear guidance on how organisations could implement an IT governance framework, which addresses the strategic alignment of IT to business, value delivery by IT investments, IT risk management, IT resource management and IT performance measurement.
- Full Text:
Formulation, development and assessment of tenofovir disoproxil fumarate-loaded pellets
- Authors: Dube, Tawanda
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54690 , vital:26600
- Description: Tenofovir disoproxil fumarate (TDF) is a novel nucleotide analog reverse transcriptase inhibitor that is recommended by the WHO for use in first line treatment of HIV infections. Due to the high dose of TDF for anti-retroviral treatment the formulation of a pellet dosage form may improve patient adherence by incorporation of a large dose in a relatively small dosage form. TDF is currently only available in tablet form. A simple, sensitive, selective, rapid, accurate, precise, stability indicating reversed-phase HPLC method was developed and validated in accordance with ICH guidelines and was successfully used for the analysis of TDF raw material and pharmaceutical dosage forms. Preformulation studies included an investigation of TDF-excipient and excipient-excipient interactions with all materials that could potentially be used to produce extruded and spheronized pellets. Nuclear Magnetic Resonance spectroscopy (NMR), Infrared Spectroscopy (IR), Differential Scanning Colorimetry (DSC) and Thermogravimetric analysis were used for identification and purity testing of TDF and all excipients. DSC data revealed that no potential interactions between TDF and the excipients occurred suggesting that incompatibility reactions were unlikely during manufacture and storage. These findings were confirmed by IR analysis that revealed that no physical interaction was likely between any of the excipients used and TDF. DSC data also reveal the existence of the α and β-polymorphs of TDF as evidenced by two enthalpy changes observed on the resultant thermograms. The existence of two polymorphs is unlikely to result in incompatibility and was confirmed by IR analysis. The IR spectra reveal that all characteristic peaks for TDF were present in 1:1 binary mixtures. Therefore TDF is compatible with all excipients tested and thermal analysis confirmed the stability of TDF under manufacturing conditions. The temperature of degradation temperature established through DSC analysis confirmed that degradation during manufacture is unlikely as the temperature of manufacture is lower than that at which degradation occurs. Extrusion and spheronization were the processes used to manufacture TDF pellets as it is a simple and economic approach for production. The effects of extruder and spheronizer speed, amount of spheronization aid and diluents on the pellet size, shape, flow properties and TDF release characteristics were examined. In order to decrease the complexity of analysis and reduce the cost of development a Taguchi orthogonal array design of experiments was successfully applied to evaluate the impact of formulation variables on product characteristics and predict an optimized formulation with a minimum number of experiments. The use of Response Surface Methodology for the development and optimization of pharmaceutical systems, including the optimization of formulation composition, manufacturing processes and/or analytical methods is well established. However the application of RSM requires that accurate, precise and reproducible experimental conditions are used for the generation of reliable data and RSM use is limited due to sensitivity to experimental variability. The benefits of using RSM for formulation optimization include the fact that more than one variable can be investigated at a time and large amounts of information can be generated at the same time ensuring a more efficient process with respect to time and cost. An added advantage of this approach is that mathematical relationships can be generated for the models that are produced and provide formulation scientists with an indication of whether the effect(s) between factors are synergistic or antagonistic. There are several statistical design approaches that use RSM and a Taguchi orthogonal array design was selected for use in this optimization process as fewer experiments are required to generate data for the same number of factors to be investigated when compared to other statistical designs such as Central Composite (CCD) and Box-Behnken designs. The use of RSM clearly demonstrates the impact of different input variables on the % TDF released at 45 min and % TDF loaded into the particles. The amount of sorbitol and Kollidon® CL-M were the only significant variables that affected the % TDF released at 45 min and both excipients had an overall synergistic effect on the in vitro release of TDF. The prediction and manufacture of an optimized formulation led to the production of pellets that met predetermined specifications which was successfully achieved using RSM. The development of a TDF containing pellet dosage form has been achieved and the formulation, manufacture and characterization of the dosage form reveal that the product has the potential to be further developed.
- Full Text:
- Authors: Dube, Tawanda
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54690 , vital:26600
- Description: Tenofovir disoproxil fumarate (TDF) is a novel nucleotide analog reverse transcriptase inhibitor that is recommended by the WHO for use in first line treatment of HIV infections. Due to the high dose of TDF for anti-retroviral treatment the formulation of a pellet dosage form may improve patient adherence by incorporation of a large dose in a relatively small dosage form. TDF is currently only available in tablet form. A simple, sensitive, selective, rapid, accurate, precise, stability indicating reversed-phase HPLC method was developed and validated in accordance with ICH guidelines and was successfully used for the analysis of TDF raw material and pharmaceutical dosage forms. Preformulation studies included an investigation of TDF-excipient and excipient-excipient interactions with all materials that could potentially be used to produce extruded and spheronized pellets. Nuclear Magnetic Resonance spectroscopy (NMR), Infrared Spectroscopy (IR), Differential Scanning Colorimetry (DSC) and Thermogravimetric analysis were used for identification and purity testing of TDF and all excipients. DSC data revealed that no potential interactions between TDF and the excipients occurred suggesting that incompatibility reactions were unlikely during manufacture and storage. These findings were confirmed by IR analysis that revealed that no physical interaction was likely between any of the excipients used and TDF. DSC data also reveal the existence of the α and β-polymorphs of TDF as evidenced by two enthalpy changes observed on the resultant thermograms. The existence of two polymorphs is unlikely to result in incompatibility and was confirmed by IR analysis. The IR spectra reveal that all characteristic peaks for TDF were present in 1:1 binary mixtures. Therefore TDF is compatible with all excipients tested and thermal analysis confirmed the stability of TDF under manufacturing conditions. The temperature of degradation temperature established through DSC analysis confirmed that degradation during manufacture is unlikely as the temperature of manufacture is lower than that at which degradation occurs. Extrusion and spheronization were the processes used to manufacture TDF pellets as it is a simple and economic approach for production. The effects of extruder and spheronizer speed, amount of spheronization aid and diluents on the pellet size, shape, flow properties and TDF release characteristics were examined. In order to decrease the complexity of analysis and reduce the cost of development a Taguchi orthogonal array design of experiments was successfully applied to evaluate the impact of formulation variables on product characteristics and predict an optimized formulation with a minimum number of experiments. The use of Response Surface Methodology for the development and optimization of pharmaceutical systems, including the optimization of formulation composition, manufacturing processes and/or analytical methods is well established. However the application of RSM requires that accurate, precise and reproducible experimental conditions are used for the generation of reliable data and RSM use is limited due to sensitivity to experimental variability. The benefits of using RSM for formulation optimization include the fact that more than one variable can be investigated at a time and large amounts of information can be generated at the same time ensuring a more efficient process with respect to time and cost. An added advantage of this approach is that mathematical relationships can be generated for the models that are produced and provide formulation scientists with an indication of whether the effect(s) between factors are synergistic or antagonistic. There are several statistical design approaches that use RSM and a Taguchi orthogonal array design was selected for use in this optimization process as fewer experiments are required to generate data for the same number of factors to be investigated when compared to other statistical designs such as Central Composite (CCD) and Box-Behnken designs. The use of RSM clearly demonstrates the impact of different input variables on the % TDF released at 45 min and % TDF loaded into the particles. The amount of sorbitol and Kollidon® CL-M were the only significant variables that affected the % TDF released at 45 min and both excipients had an overall synergistic effect on the in vitro release of TDF. The prediction and manufacture of an optimized formulation led to the production of pellets that met predetermined specifications which was successfully achieved using RSM. The development of a TDF containing pellet dosage form has been achieved and the formulation, manufacture and characterization of the dosage form reveal that the product has the potential to be further developed.
- Full Text: