Determination of the effects of sunlight and UV irradiation on the structure, viability and reapplication frequency of the biopesticide cryptophlebia leucotreta granulovirus in the protection against false codling moth infestation of citrus crops
- Authors: Mwanza, Patrick
- Date: 2015
- Subjects: Cryptophlebia leucotreta -- Effect of ultraviolet radiation on , Natural pesticides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/6346 , vital:21075
- Description: Cryptophlebia leucotreta granulovirus (CrleGV-SA) is a baculovirus specifically pathogenic to the citrus pest false codling moth, Thaumatotibia leucotreta. CrleGV- SA is formulated as a commercial biopesticide, Cryptogran® (River Bioscience, South Africa). The virus has a stable, proteinaceous crystalline occlusion body (OB) that protects the nucleocapsid. The major limitation to the use of baculoviruses is their susceptibility to the ultraviolet (UV) component of sunlight, which rapidly and greatly reduces their efficacy as biopesticides. The UVA and UVB components are the most destructive to biological organisms. To date no publication has reported the effect of UV on the structure and virulence of CrleGV, or the effectiveness of the OB as a UV protectant. In this study the effect of UV irradiation on the structure and infectivity of pure CrleGV-SA and Cryptogran® was investigated using scanning electron microscopy (SEM), Raman spectroscopy, qPCR, and bioassays. The project included laboratory and field studies. In the laboratory, CrleGV-SA and Cryptogran® were exposed to either UVA or UVB for periods of 24 hours to 7 days before analysis. In the field, Cryptogran® was applied to trees in a citrus orchard with young fruit. The fruit were collected from 24 hours to 28 days after application and bioassays conducted to assess the effect of sunlight over time on virus structure and efficacy when applied to the northern or southern sides of the trees. No surface morphological changes to the virus were detected using SEM. However, small compositional changes were detected by Raman spectroscopy. qPCR and bioassays demonstrated that UV irradiation damaged the viral DNA, greatly reducing the infectivity of pure CrleGV-SA and Cryptogran®. Exposure to UVB reduced the virulence of the virus more than UVA. The field studies revealed that the activity of CrleGV-SA decreased more on the northern side of the trees than on the southern side.
- Full Text:
- Date Issued: 2015
- Authors: Mwanza, Patrick
- Date: 2015
- Subjects: Cryptophlebia leucotreta -- Effect of ultraviolet radiation on , Natural pesticides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/6346 , vital:21075
- Description: Cryptophlebia leucotreta granulovirus (CrleGV-SA) is a baculovirus specifically pathogenic to the citrus pest false codling moth, Thaumatotibia leucotreta. CrleGV- SA is formulated as a commercial biopesticide, Cryptogran® (River Bioscience, South Africa). The virus has a stable, proteinaceous crystalline occlusion body (OB) that protects the nucleocapsid. The major limitation to the use of baculoviruses is their susceptibility to the ultraviolet (UV) component of sunlight, which rapidly and greatly reduces their efficacy as biopesticides. The UVA and UVB components are the most destructive to biological organisms. To date no publication has reported the effect of UV on the structure and virulence of CrleGV, or the effectiveness of the OB as a UV protectant. In this study the effect of UV irradiation on the structure and infectivity of pure CrleGV-SA and Cryptogran® was investigated using scanning electron microscopy (SEM), Raman spectroscopy, qPCR, and bioassays. The project included laboratory and field studies. In the laboratory, CrleGV-SA and Cryptogran® were exposed to either UVA or UVB for periods of 24 hours to 7 days before analysis. In the field, Cryptogran® was applied to trees in a citrus orchard with young fruit. The fruit were collected from 24 hours to 28 days after application and bioassays conducted to assess the effect of sunlight over time on virus structure and efficacy when applied to the northern or southern sides of the trees. No surface morphological changes to the virus were detected using SEM. However, small compositional changes were detected by Raman spectroscopy. qPCR and bioassays demonstrated that UV irradiation damaged the viral DNA, greatly reducing the infectivity of pure CrleGV-SA and Cryptogran®. Exposure to UVB reduced the virulence of the virus more than UVA. The field studies revealed that the activity of CrleGV-SA decreased more on the northern side of the trees than on the southern side.
- Full Text:
- Date Issued: 2015
Determining the competency of children with developmental delays to testify in criminal trials
- Authors: Van Niekerk, Hester Aletta
- Date: 2015
- Subjects: Child witnesses -- South Africa , Developmentally disabled children -- South Africa , Children -- Legal status, laws, etc. -- South Africa , Evidence (Law) -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3722 , http://hdl.handle.net/10962/d1017878
- Description: In South Africa children are required to testify under oath or admonition. The shortcomings of the competency test are of particular relevance to children with developmental disabilities, since courts are not equipped to adequately assess the competency of these children to give evidence. One component of testimonial competency, namely the understanding of the concepts truth and lies, is overemphasised and is examined with questions that are developmentally inappropriate for child witnesses in general. For children with cognitive disabilities, such questions create barriers for participation in the truth-seeking process. Consequently, convictions have been set aside on appeal owing to procedural irregularities found in the implementation of this test. In the literature review on testimonial competency, attention was given to restrictions that specific developmental disabilities impose on the perceptual, cognitive, communication and moral development of children. Two of four components – narrative ability and moral capacity – were studied in a sample of 184 children in middle childhood. Participants’ ability to give coherent and detailed accounts of events, their understanding of the concepts truth, lies, promises and the oath, and the Lyon and Saywitz oath-taking competency test, were investigated. Quantitative and qualitative methods were used for data analysis. Three groups were identified: those children with very limited, average or full testimonial competency. Their capacities were found to be related to maturation of cognitive functions and level of intellectual functioning. Participants were better able to demonstrate their understanding of truth and falsity by responding to the oathtaking test than giving verbal descriptions of these concepts. Whereas 1 percent of participants had a conceptual understanding of an oath, 15 percent understood the concept of a promise. Syncretism and confabulation compromised the narrative accounts of a substantial number of participants. Syncretism relates to immature narrative ability: correct details are combined in an illogical fashion. Confabulation refers to filling memory gaps with fabricated information. Guidelines on the competency determination of children with developmental disabilities were compiled. It is suggested that the competency examination be replaced by a formal, pre-trial competency assessment. The court should also receive expert evidence on how to facilitate meaningful participation when a child with sufficient testimonial competence is the witness.
- Full Text:
- Date Issued: 2015
- Authors: Van Niekerk, Hester Aletta
- Date: 2015
- Subjects: Child witnesses -- South Africa , Developmentally disabled children -- South Africa , Children -- Legal status, laws, etc. -- South Africa , Evidence (Law) -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3722 , http://hdl.handle.net/10962/d1017878
- Description: In South Africa children are required to testify under oath or admonition. The shortcomings of the competency test are of particular relevance to children with developmental disabilities, since courts are not equipped to adequately assess the competency of these children to give evidence. One component of testimonial competency, namely the understanding of the concepts truth and lies, is overemphasised and is examined with questions that are developmentally inappropriate for child witnesses in general. For children with cognitive disabilities, such questions create barriers for participation in the truth-seeking process. Consequently, convictions have been set aside on appeal owing to procedural irregularities found in the implementation of this test. In the literature review on testimonial competency, attention was given to restrictions that specific developmental disabilities impose on the perceptual, cognitive, communication and moral development of children. Two of four components – narrative ability and moral capacity – were studied in a sample of 184 children in middle childhood. Participants’ ability to give coherent and detailed accounts of events, their understanding of the concepts truth, lies, promises and the oath, and the Lyon and Saywitz oath-taking competency test, were investigated. Quantitative and qualitative methods were used for data analysis. Three groups were identified: those children with very limited, average or full testimonial competency. Their capacities were found to be related to maturation of cognitive functions and level of intellectual functioning. Participants were better able to demonstrate their understanding of truth and falsity by responding to the oathtaking test than giving verbal descriptions of these concepts. Whereas 1 percent of participants had a conceptual understanding of an oath, 15 percent understood the concept of a promise. Syncretism and confabulation compromised the narrative accounts of a substantial number of participants. Syncretism relates to immature narrative ability: correct details are combined in an illogical fashion. Confabulation refers to filling memory gaps with fabricated information. Guidelines on the competency determination of children with developmental disabilities were compiled. It is suggested that the competency examination be replaced by a formal, pre-trial competency assessment. The court should also receive expert evidence on how to facilitate meaningful participation when a child with sufficient testimonial competence is the witness.
- Full Text:
- Date Issued: 2015
Detriments associated with substance abuse among out - of - school youth in Ntselamanzi, village, Alice Town
- Authors: Chatikobo, Nyasha
- Date: 2015
- Subjects: Substance abuse--South Africa--Eastern Cape , Drug abuse--South Africa--Eastern Cape , Youth--Substance use--South Africa--Eastern Cape
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/19442 , vital:43087
- Description: The main aim of the study was to investigate the detriments associated with substance abuse among the out- of- school youth of Ntselamanzi Village in Alice. This study intended to achieve the following objectives. (i) to establish the causes of increased indulgence in substance abuse in Ntselamanzi village, Eastern Cape. (ii) to identify the various kinds of drugs abused by the society of Ntselamanzi (iii) to identify the consequences of substance abuse to the lives of the out-of-school youth. (iv) to suggest the strategies that can be used to reduce substance abuse in order to enhance the youth‟s socio-economic growth and societal bliss. Using the quantitative method ninety-eight questionnaires were administered to the out-of-school youth in Ntselamanzi village and eighty questionnaires were returned fully answered. The major findings of the study outlined that dominating factors of substance abuse in Ntselamanzi village were family drug use, increased drug accessibility, lack of recreation and peer influence. As a result drug abuse among the out of school youth has indicated that the youth end up dropping out of school, unemployed, facing health complications and committing anti-social activities in the village which causing family conflicts and rifts in the community. These all affected the out-of-school youths‟ well-being, academic future and their quality of life was lowered due to all related issues with drug abuse. It can be concluded that drug use among rural outof-school youth is detrimental to the out-of-school youths, their families destroyed and their community crippled from the anti-social activities that take place. The future of the youths‟ education is hampered; the quality of persons in the community and families is lowered. Having unproductive out-of-school youth as a result of drug abuse is not good for the development of the village and all the persons therein. , Thesis (M Soc Sc) (Social Work) -- University of Fort Hare, 2015
- Full Text:
- Date Issued: 2015
- Authors: Chatikobo, Nyasha
- Date: 2015
- Subjects: Substance abuse--South Africa--Eastern Cape , Drug abuse--South Africa--Eastern Cape , Youth--Substance use--South Africa--Eastern Cape
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/19442 , vital:43087
- Description: The main aim of the study was to investigate the detriments associated with substance abuse among the out- of- school youth of Ntselamanzi Village in Alice. This study intended to achieve the following objectives. (i) to establish the causes of increased indulgence in substance abuse in Ntselamanzi village, Eastern Cape. (ii) to identify the various kinds of drugs abused by the society of Ntselamanzi (iii) to identify the consequences of substance abuse to the lives of the out-of-school youth. (iv) to suggest the strategies that can be used to reduce substance abuse in order to enhance the youth‟s socio-economic growth and societal bliss. Using the quantitative method ninety-eight questionnaires were administered to the out-of-school youth in Ntselamanzi village and eighty questionnaires were returned fully answered. The major findings of the study outlined that dominating factors of substance abuse in Ntselamanzi village were family drug use, increased drug accessibility, lack of recreation and peer influence. As a result drug abuse among the out of school youth has indicated that the youth end up dropping out of school, unemployed, facing health complications and committing anti-social activities in the village which causing family conflicts and rifts in the community. These all affected the out-of-school youths‟ well-being, academic future and their quality of life was lowered due to all related issues with drug abuse. It can be concluded that drug use among rural outof-school youth is detrimental to the out-of-school youths, their families destroyed and their community crippled from the anti-social activities that take place. The future of the youths‟ education is hampered; the quality of persons in the community and families is lowered. Having unproductive out-of-school youth as a result of drug abuse is not good for the development of the village and all the persons therein. , Thesis (M Soc Sc) (Social Work) -- University of Fort Hare, 2015
- Full Text:
- Date Issued: 2015
Developed teacher leadership in a township high school : an interpretive case study
- Authors: John, Daisy Mary
- Date: 2015
- Subjects: Educational leadership -- South Africa -- Eastern Cape , School management and organization -- South Africa -- Eastern Cape , Teacher participation in administration -- South Africa -- Eastern Cape , Teacher effectiveness -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2052 , http://hdl.handle.net/10962/d1018548
- Description: South Africa’s future success depends on a number of national priorities, amongst them the transformation of its education system. Education is the best route to follow to alleviate poverty and many other social ills. One way to overcome some of the complex challenges and crises that we face in South African schools is to pay attention to issues of leading and leadership, including the leadership of teachers. This study is done with the hope that research into teacher leadership will be one of the answers to the crisis in education. It should become a beacon of hope for all educationists who passionately want progress in the youth of South Africa. What better way than to ‘Awaken the Sleeping Giant’ of teacher leadership, borrowing the term from Katzenmeyer and Moller (2009). This study was designed as a case study, the purpose of which was to find out about the enactment of teacher leadership in an Eastern Cape township high school as well as the enhancing and hindering factors to this enactment. This study was done as a replication study of a similar study done by a group of 11Master’s students at the University of KwaZulu-Natal in 2010. Similar to the original study, this case study was located within the interpretive paradigm and drew on school profiling, survey questionnaires, a focus group interview, selfreflective journals and individual interviews for its methods of data collection. The study was framed by distributed leadership while Grant’s (2008; 2012) Model of teacher leadership was adopted as the analytical tool. It emerged from the data that the three teacher leaders, my primary participants, exhibited teacher leadership across all four zones of Grant’s (2008) Model. The first zone was leadership in the classroom where all three teacher leaders showed leadership to varying degrees. Zones Two to Four are about leadership beyond the classroom into the school and beyond. In Zone Two, the zone where teachers work with each other and the learners outside the classroom, substantial levels of leadership were enacted by the three teacher leaders. Zone Three, where leadership is exhibited in whole-school development, the three primary participants showed distinct leadership qualities as well. The fourth zone, which is about interaction with neighbouring schools, also revealed that all three teacher leaders demonstrated active leadership on a regular basis. Findings further revealed that there were only a few inhibiting factors to the leadership of teachers at the case study school, including limited resources and infrastructure as well as insufficient support and acknowledgement from the relevant stakeholders when leadership initiatives were made, either successfully or otherwise. However, the enhancing factors superseded the inhibiting factors. A functional committee culture guided by a shared vision existed in the case study school together with an ethos of trust which enabled the staff to work collaboratively. Though there was certainly room for improvement in leadership practices at this case study school, the enactment of teacher leadership in this school illustrated a strong case of ‘developed’ teacher leadership (Muijs& Harris, 2007) within a dispersed leadership framing (Gunter, 2005)
- Full Text:
- Date Issued: 2015
- Authors: John, Daisy Mary
- Date: 2015
- Subjects: Educational leadership -- South Africa -- Eastern Cape , School management and organization -- South Africa -- Eastern Cape , Teacher participation in administration -- South Africa -- Eastern Cape , Teacher effectiveness -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2052 , http://hdl.handle.net/10962/d1018548
- Description: South Africa’s future success depends on a number of national priorities, amongst them the transformation of its education system. Education is the best route to follow to alleviate poverty and many other social ills. One way to overcome some of the complex challenges and crises that we face in South African schools is to pay attention to issues of leading and leadership, including the leadership of teachers. This study is done with the hope that research into teacher leadership will be one of the answers to the crisis in education. It should become a beacon of hope for all educationists who passionately want progress in the youth of South Africa. What better way than to ‘Awaken the Sleeping Giant’ of teacher leadership, borrowing the term from Katzenmeyer and Moller (2009). This study was designed as a case study, the purpose of which was to find out about the enactment of teacher leadership in an Eastern Cape township high school as well as the enhancing and hindering factors to this enactment. This study was done as a replication study of a similar study done by a group of 11Master’s students at the University of KwaZulu-Natal in 2010. Similar to the original study, this case study was located within the interpretive paradigm and drew on school profiling, survey questionnaires, a focus group interview, selfreflective journals and individual interviews for its methods of data collection. The study was framed by distributed leadership while Grant’s (2008; 2012) Model of teacher leadership was adopted as the analytical tool. It emerged from the data that the three teacher leaders, my primary participants, exhibited teacher leadership across all four zones of Grant’s (2008) Model. The first zone was leadership in the classroom where all three teacher leaders showed leadership to varying degrees. Zones Two to Four are about leadership beyond the classroom into the school and beyond. In Zone Two, the zone where teachers work with each other and the learners outside the classroom, substantial levels of leadership were enacted by the three teacher leaders. Zone Three, where leadership is exhibited in whole-school development, the three primary participants showed distinct leadership qualities as well. The fourth zone, which is about interaction with neighbouring schools, also revealed that all three teacher leaders demonstrated active leadership on a regular basis. Findings further revealed that there were only a few inhibiting factors to the leadership of teachers at the case study school, including limited resources and infrastructure as well as insufficient support and acknowledgement from the relevant stakeholders when leadership initiatives were made, either successfully or otherwise. However, the enhancing factors superseded the inhibiting factors. A functional committee culture guided by a shared vision existed in the case study school together with an ethos of trust which enabled the staff to work collaboratively. Though there was certainly room for improvement in leadership practices at this case study school, the enactment of teacher leadership in this school illustrated a strong case of ‘developed’ teacher leadership (Muijs& Harris, 2007) within a dispersed leadership framing (Gunter, 2005)
- Full Text:
- Date Issued: 2015
Developing a cross platform IMS client using the JAIN SIP applet phone
- Authors: Muswera, Walter Tawanda
- Date: 2015
- Subjects: Internet Protocol multimedia subsystem , Java (Computer program language)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4712 , http://hdl.handle.net/10962/d1017934
- Description: Since the introduction of the IP Multimedia Subsystem (IMS) by the Third Generation Partnership Project (3GPP) in 2002, a lot of research has been conducted aimed at designing and implementing IMS capable clients and network elements. Though considerable work has been done in the development of IMS clients, there is no single, free and open source IMS client that provides researchers with all the required functionality needed to test the applications they are developing. For example, several open and closed source SIP/IMS clients are used within the Rhodes University Conver- gence Research Group (RUCRG) to test applications under development, as a result of the fact that the various SIP/IMS clients support different subsets of SIP/IMS features. The lack of a single client and the subsequent use of various clients comes with several problems. Researchers have to know how to deploy, configure, use and at times adapt the various clients to suit their needs. This can be very time consuming and, in fact, contradicts the IMS philosophy (the IMS was proposed to support rapid service creation). This thesis outlines the development of a Java-based, IMS compliant client called RUCRG IMS client, that uses the JAIN SIP Applet Phone (JSAP) as its foundation. JSAP, which originally offered only basic voice calling and instant messaging (IM) capabilities, was modified to be IMS compliant and support video calls, IM and presence using XML Configuration Access Protocol (XCAP).
- Full Text:
- Date Issued: 2015
- Authors: Muswera, Walter Tawanda
- Date: 2015
- Subjects: Internet Protocol multimedia subsystem , Java (Computer program language)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4712 , http://hdl.handle.net/10962/d1017934
- Description: Since the introduction of the IP Multimedia Subsystem (IMS) by the Third Generation Partnership Project (3GPP) in 2002, a lot of research has been conducted aimed at designing and implementing IMS capable clients and network elements. Though considerable work has been done in the development of IMS clients, there is no single, free and open source IMS client that provides researchers with all the required functionality needed to test the applications they are developing. For example, several open and closed source SIP/IMS clients are used within the Rhodes University Conver- gence Research Group (RUCRG) to test applications under development, as a result of the fact that the various SIP/IMS clients support different subsets of SIP/IMS features. The lack of a single client and the subsequent use of various clients comes with several problems. Researchers have to know how to deploy, configure, use and at times adapt the various clients to suit their needs. This can be very time consuming and, in fact, contradicts the IMS philosophy (the IMS was proposed to support rapid service creation). This thesis outlines the development of a Java-based, IMS compliant client called RUCRG IMS client, that uses the JAIN SIP Applet Phone (JSAP) as its foundation. JSAP, which originally offered only basic voice calling and instant messaging (IM) capabilities, was modified to be IMS compliant and support video calls, IM and presence using XML Configuration Access Protocol (XCAP).
- Full Text:
- Date Issued: 2015
Developing a GIS based method for school site identification in the rural Eastern Cape
- Authors: Swart, Conrad Dirk
- Date: 2015
- Subjects: Geographic information systems -- South Africa -- Eastern Cape , School sites -- South Africa -- Eastern Cape , School sites -- South Africa -- Eastern Cape -- Planning , Rural schools -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4891 , http://hdl.handle.net/10962/d1018939
- Description: Historically, South Africa has not had equal education in terms of funding, curriculum or physical resources and structures. These issues are still present in contemporary South Africa and none more so than the issues surrounding “mud schools”. Recently the Department of Basic Education (DBE) implemented a plan to eradicate inappropriate school structures using the Accelerated Schools Infrastructure Delivery Initiative program (ASIDI). Questions around effective placement of schools are now being asked. Using interviews and analysis of literature, this research developed criteria needed to determine how rural school sites are selected. Geographical Information Systems (GIS) was used to determine if current sites are in the most appropriate areas. The results of the research included a unique set of Eastern Cape criteria as well as an analysis of the current site selection methods used by the DBE. It also revealed that most of the schools are being constructed in acceptable areas. The main result that emerged from the research was that schools will be placed in areas where they are needed. Developing site selection criteria is still needed as South Africa seeks to reduce the education gap between rich and poor schools.
- Full Text:
- Date Issued: 2015
- Authors: Swart, Conrad Dirk
- Date: 2015
- Subjects: Geographic information systems -- South Africa -- Eastern Cape , School sites -- South Africa -- Eastern Cape , School sites -- South Africa -- Eastern Cape -- Planning , Rural schools -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4891 , http://hdl.handle.net/10962/d1018939
- Description: Historically, South Africa has not had equal education in terms of funding, curriculum or physical resources and structures. These issues are still present in contemporary South Africa and none more so than the issues surrounding “mud schools”. Recently the Department of Basic Education (DBE) implemented a plan to eradicate inappropriate school structures using the Accelerated Schools Infrastructure Delivery Initiative program (ASIDI). Questions around effective placement of schools are now being asked. Using interviews and analysis of literature, this research developed criteria needed to determine how rural school sites are selected. Geographical Information Systems (GIS) was used to determine if current sites are in the most appropriate areas. The results of the research included a unique set of Eastern Cape criteria as well as an analysis of the current site selection methods used by the DBE. It also revealed that most of the schools are being constructed in acceptable areas. The main result that emerged from the research was that schools will be placed in areas where they are needed. Developing site selection criteria is still needed as South Africa seeks to reduce the education gap between rich and poor schools.
- Full Text:
- Date Issued: 2015
Developing a performance measurement tool to monitor the performance of a public sector agency : a balanced scorecard approach
- Authors: Lisani, Ncedo
- Date: 2015
- Subjects: South Africa. Economic Development Department , South Africa. Department of Environmental Affairs and Tourism , Performance -- Measurement , Performance -- Management , Public administration -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:848 , http://hdl.handle.net/10962/d1017515
- Description: The world has seen unparalleled pressure put on the public sector to improve the speed and quality of service delivery, whilst simultaneously employing measures to cut the costs. South Africa and the Eastern Cape have not been immune to this as there have been complaints and demonstrations from various national and provincial stakeholders demanding more and improved services. The Department of Economic Development, Environmental Affairs and Tourism (DEDEAT) in particular has employed the services of public entities in its quest to realise government’s socio-economic developmental objectives and ease some of the service delivery pressures. These agencies are unfortunately struggling to deliver and the Department is unable to play the oversight role it is legislatively mandated to carry out. The main reason for this seem to be the lack of the capacity to objectively track and measure the performance of these agencies. As they say “you cannot manage what you cannot measure”. This is despite the fact that there is a shareholders’ compact and many other measures in place to enable performance monitoring. Also, the public sector is known to have inherent and unique performance management challenges like broad and vague objectives which lead to too many measurements, a propensity to focus on the “easy to measure” but often irrelevant indicators at the expense of critical outcomes and a short-term orientation that is usually fuelled by political expediency. Against this background, this study sought to make use of a comprehensive and dynamic performance monitoring framework, namely the Balanced Scorecard (BSC), to explore its potential use in assisting government to monitor the performance of public agencies, in particular the Development Finance Institutions (DFI) in South Africa. The proposed framework helps government to focus on the performance drivers of future value, and what decisions and actions are necessary to achieve critical outcomes. The aim of the study therefore is to develop an adjusted BSC framework to monitor the activities of a public sector agency and thus demonstrate how a BSC framework could be used to monitor a public agency by the government department. The study is evaluative in nature and is divided into three sections. Section one is presented as an Evaluation Report. It sets the scene, discusses briefly the key theoretical concepts, outlines the research methods used and presents the findings followed by a discussion and recommendations. Section two delves into the literature in more detail, providing a more extensive review of the literature that informed the investigation, whilst section three provides a more extensive description of the research methodology employed in the study. To achieve the aims of the study, the research drew from the work of various authors in the field including that of Bigliardi, Dormio and Galati, 2011; Bititci, Garengo, Dörfler, and Nudurupati, 2012; Julyan, 2011; Kaplan and Norton, 1992, 1993, 1996, 2001, 2004 and 2006; Niven, 2003 and 2008 and Northcott and Taulapapa, 2012. Also, five BSC perspectives - including the programme specific “equity” perspective - were used to develop an interview schedule. These were used to formulate the key performance objectives and indicators, based on the stakeholder’s responses. These respondents have experience within the programme as administrators, beneficiaries and funders. The research employed purposive sampling with semi-structured in-depth interviews and document analysis as primary and secondary instruments for data collection. In essence, five officials from the agency, one from DEDEAT and two co-operatives participated in the research. The results indicate a general appreciation of and gravitation towards outcome based measures, even though the government culture of focusing on outputs is still prevalent. The results of the study indicated that, generally, a government - public agency BSC based performance monitoring framework would have the following features: Customer objectives and programme mission as the main goal and this will provides clarity at all levels on who the customers are and what are their primary requirements. Clear, visible and stringent financial controls as the agency is administering public resources. Few carefully selected processes and systems that have a direct and positive impact on the customer objectives. Deliberate and consistent efforts to promote the participation of designated groups in the economy of the country. Comprehensive indicators on capacity building as “mission based-organisations rely heavily on skills, dedication and alignment of staff”. Overall, the study concludes that the make-up of the BSC is beneficial to the public sector and in monitoring the public sector agencies for the following reasons: It helps the agency to focus on customers and their needs. It forces the agency to engage and communicate strategic intention with both internal and external stakeholders and thus synchronize competing stakeholder needs. It forces the agency to limit the number of indicators and therefore select the few value adding measures that are aligned to customer outcomes. Through its cause and effect relationship, the agency is compelled to align all the resources, activities and processes to the main goal of the entity. All these help to minimize the principal agent problem, as the use of the BSC can bring clarity on strategy and expectations, provided it is supported with regular communication.
- Full Text:
- Date Issued: 2015
- Authors: Lisani, Ncedo
- Date: 2015
- Subjects: South Africa. Economic Development Department , South Africa. Department of Environmental Affairs and Tourism , Performance -- Measurement , Performance -- Management , Public administration -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:848 , http://hdl.handle.net/10962/d1017515
- Description: The world has seen unparalleled pressure put on the public sector to improve the speed and quality of service delivery, whilst simultaneously employing measures to cut the costs. South Africa and the Eastern Cape have not been immune to this as there have been complaints and demonstrations from various national and provincial stakeholders demanding more and improved services. The Department of Economic Development, Environmental Affairs and Tourism (DEDEAT) in particular has employed the services of public entities in its quest to realise government’s socio-economic developmental objectives and ease some of the service delivery pressures. These agencies are unfortunately struggling to deliver and the Department is unable to play the oversight role it is legislatively mandated to carry out. The main reason for this seem to be the lack of the capacity to objectively track and measure the performance of these agencies. As they say “you cannot manage what you cannot measure”. This is despite the fact that there is a shareholders’ compact and many other measures in place to enable performance monitoring. Also, the public sector is known to have inherent and unique performance management challenges like broad and vague objectives which lead to too many measurements, a propensity to focus on the “easy to measure” but often irrelevant indicators at the expense of critical outcomes and a short-term orientation that is usually fuelled by political expediency. Against this background, this study sought to make use of a comprehensive and dynamic performance monitoring framework, namely the Balanced Scorecard (BSC), to explore its potential use in assisting government to monitor the performance of public agencies, in particular the Development Finance Institutions (DFI) in South Africa. The proposed framework helps government to focus on the performance drivers of future value, and what decisions and actions are necessary to achieve critical outcomes. The aim of the study therefore is to develop an adjusted BSC framework to monitor the activities of a public sector agency and thus demonstrate how a BSC framework could be used to monitor a public agency by the government department. The study is evaluative in nature and is divided into three sections. Section one is presented as an Evaluation Report. It sets the scene, discusses briefly the key theoretical concepts, outlines the research methods used and presents the findings followed by a discussion and recommendations. Section two delves into the literature in more detail, providing a more extensive review of the literature that informed the investigation, whilst section three provides a more extensive description of the research methodology employed in the study. To achieve the aims of the study, the research drew from the work of various authors in the field including that of Bigliardi, Dormio and Galati, 2011; Bititci, Garengo, Dörfler, and Nudurupati, 2012; Julyan, 2011; Kaplan and Norton, 1992, 1993, 1996, 2001, 2004 and 2006; Niven, 2003 and 2008 and Northcott and Taulapapa, 2012. Also, five BSC perspectives - including the programme specific “equity” perspective - were used to develop an interview schedule. These were used to formulate the key performance objectives and indicators, based on the stakeholder’s responses. These respondents have experience within the programme as administrators, beneficiaries and funders. The research employed purposive sampling with semi-structured in-depth interviews and document analysis as primary and secondary instruments for data collection. In essence, five officials from the agency, one from DEDEAT and two co-operatives participated in the research. The results indicate a general appreciation of and gravitation towards outcome based measures, even though the government culture of focusing on outputs is still prevalent. The results of the study indicated that, generally, a government - public agency BSC based performance monitoring framework would have the following features: Customer objectives and programme mission as the main goal and this will provides clarity at all levels on who the customers are and what are their primary requirements. Clear, visible and stringent financial controls as the agency is administering public resources. Few carefully selected processes and systems that have a direct and positive impact on the customer objectives. Deliberate and consistent efforts to promote the participation of designated groups in the economy of the country. Comprehensive indicators on capacity building as “mission based-organisations rely heavily on skills, dedication and alignment of staff”. Overall, the study concludes that the make-up of the BSC is beneficial to the public sector and in monitoring the public sector agencies for the following reasons: It helps the agency to focus on customers and their needs. It forces the agency to engage and communicate strategic intention with both internal and external stakeholders and thus synchronize competing stakeholder needs. It forces the agency to limit the number of indicators and therefore select the few value adding measures that are aligned to customer outcomes. Through its cause and effect relationship, the agency is compelled to align all the resources, activities and processes to the main goal of the entity. All these help to minimize the principal agent problem, as the use of the BSC can bring clarity on strategy and expectations, provided it is supported with regular communication.
- Full Text:
- Date Issued: 2015
Developing and using an assessment instrument for spatial skills in Grade 10 geometry learners
- Authors: Cowley, Jane
- Date: 2015
- Subjects: Geometry -- Study and teaching (Secondary) -- South Africa -- Eastern Cape , Geometry -- Evaluation. , Mathematics -- Study and teaching (Secondary)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2025 , http://hdl.handle.net/10962/d1017336
- Description: This qualitative investigation took the form of a case study and fell within the interpretive research paradigm. The Mathematics Chair at the Education Department of Rhodes University launched the Mathematics Teacher Enrichment Programme (MTEP) in 2010 in order to combat poor Mathematics performance of learners in the lower Albany district of the Eastern Cape. The challenge that the participating MTEP teachers faced was a lack of time available to implement new teaching ideas. This was because most of their time was spent catching up “lost” or untaught concepts in the classroom. To address this problem, the Catch-Up Project was launched, whereby selected Mathematics teachers in the area taught lost concepts to Grade Ten learners during afternoon classes in an attempt to improve their fundamental Mathematics knowledge. In order to establish which sections of Mathematics were more difficult for the learners in this programme, bench mark tests were administered biannually. Whilst these tests certainly identified deficient areas within their Mathematics knowledge, the poorest performance areas were the sections of the syllabus which were spatial in nature, such as Space and Shape and Geometry. However, a more in depth assessment tool was required to establish which specific spatial skills the learners were not able to employ when doing these Geometry tasks. To this end, the Spatial Skills Assessment Tasks (SSAT) was developed. It consisted of traditional text book type Geometry tasks and real-world context tasks, both of which were used to assess six spatial skills deemed crucial to successfully facilitate learning Geometry. The case study took place in two of the schools which participated in the Grade Ten Catch-Up project. The case was focused on Grade Ten learners and the unit of analysis was their responses to the SSAT instrument. The learners that participated all did so on a strictly voluntary basis and great care was taken to protect their wellbeing and anonymity at all times. The results of the SSAT instrument revealed that the real world context tasks were in general far more successfully answered than the traditional text book type questions. Important trends in learner responses were noted and highlighted. For example, geometric terminology remains a huge challenge for learners, especially as they study Mathematics in their second language. The ability of the learners to differentiate between such concepts as congruency and similarity is severely compromised, partly due to a lack of terminological understanding but also due to a perceived lack of exposure to the material. Concepts such as verticality and horizontality also remain a huge challenge, possibly for the same reasons. They are poorly understood and yet vital to achievement in Geometry. Recommendations for the development and strengthening of spatial skills support the constructivist approach to learning. Hands on activities and intensive sustained practice over a period of a few months, in which both teachers and learners are actively involved in the learning process, would be considered most beneficial to the long term enhancement of these vital spatial skills and to the learning of Geometry in general.
- Full Text:
- Date Issued: 2015
- Authors: Cowley, Jane
- Date: 2015
- Subjects: Geometry -- Study and teaching (Secondary) -- South Africa -- Eastern Cape , Geometry -- Evaluation. , Mathematics -- Study and teaching (Secondary)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2025 , http://hdl.handle.net/10962/d1017336
- Description: This qualitative investigation took the form of a case study and fell within the interpretive research paradigm. The Mathematics Chair at the Education Department of Rhodes University launched the Mathematics Teacher Enrichment Programme (MTEP) in 2010 in order to combat poor Mathematics performance of learners in the lower Albany district of the Eastern Cape. The challenge that the participating MTEP teachers faced was a lack of time available to implement new teaching ideas. This was because most of their time was spent catching up “lost” or untaught concepts in the classroom. To address this problem, the Catch-Up Project was launched, whereby selected Mathematics teachers in the area taught lost concepts to Grade Ten learners during afternoon classes in an attempt to improve their fundamental Mathematics knowledge. In order to establish which sections of Mathematics were more difficult for the learners in this programme, bench mark tests were administered biannually. Whilst these tests certainly identified deficient areas within their Mathematics knowledge, the poorest performance areas were the sections of the syllabus which were spatial in nature, such as Space and Shape and Geometry. However, a more in depth assessment tool was required to establish which specific spatial skills the learners were not able to employ when doing these Geometry tasks. To this end, the Spatial Skills Assessment Tasks (SSAT) was developed. It consisted of traditional text book type Geometry tasks and real-world context tasks, both of which were used to assess six spatial skills deemed crucial to successfully facilitate learning Geometry. The case study took place in two of the schools which participated in the Grade Ten Catch-Up project. The case was focused on Grade Ten learners and the unit of analysis was their responses to the SSAT instrument. The learners that participated all did so on a strictly voluntary basis and great care was taken to protect their wellbeing and anonymity at all times. The results of the SSAT instrument revealed that the real world context tasks were in general far more successfully answered than the traditional text book type questions. Important trends in learner responses were noted and highlighted. For example, geometric terminology remains a huge challenge for learners, especially as they study Mathematics in their second language. The ability of the learners to differentiate between such concepts as congruency and similarity is severely compromised, partly due to a lack of terminological understanding but also due to a perceived lack of exposure to the material. Concepts such as verticality and horizontality also remain a huge challenge, possibly for the same reasons. They are poorly understood and yet vital to achievement in Geometry. Recommendations for the development and strengthening of spatial skills support the constructivist approach to learning. Hands on activities and intensive sustained practice over a period of a few months, in which both teachers and learners are actively involved in the learning process, would be considered most beneficial to the long term enhancement of these vital spatial skills and to the learning of Geometry in general.
- Full Text:
- Date Issued: 2015
Developing high-fidelity mental models of programming concepts using manipulatives and interactive metaphors
- Authors: Funcke, Matthew
- Date: 2015
- Subjects: Computer programming -- Study and teaching (Higher) , Computer programmers
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4707 , http://hdl.handle.net/10962/d1017929
- Description: It is well established that both learning and teaching programming are difficult tasks. Difficulties often occur due to weak mental models and common misconceptions. This study proposes a method of teaching programming that both encourages high-fidelity mental models and attempts to minimise misconceptions in novice programmers, through the use of metaphors and manipulatives. The elements in ActionWorld with which the students interact are realizations of metaphors. By simple example, a variable has a metaphorical representation as a labelled box that can hold a value. The dissertation develops a set of metaphors which have several core requirements: metaphors should avoid causing misconceptions, they need to be high-fidelity so as to avoid failing when used with a new concept, students must be able to relate to them, and finally, they should be usable across multiple educational media. The learning style that ActionWorld supports is one which requires active participation from the student - the system acts as a foundation upon which students are encouraged to build their mental models. This teaching style is achieved by placing the student in the role of code interpreter, the code they need to interpret will not advance until they have demonstrated its meaning via use of the aforementioned metaphors. ActionWorld was developed using an iterative developmental process that consistently improved upon various aspects of the project through a continual evaluation-enhancement cycle. The primary outputs of this project include a unified set of high-fidelity metaphors, a virtual-machine API for use in similar future projects, and two metaphor-testing games. All of the aforementioned deliverables were tested using multiple quality-evaluation criteria, the results of which were consistently positive. ActionWorld and its constituent components contribute to the wide assortment of methods one might use to teach novice programmers.
- Full Text:
- Date Issued: 2015
- Authors: Funcke, Matthew
- Date: 2015
- Subjects: Computer programming -- Study and teaching (Higher) , Computer programmers
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4707 , http://hdl.handle.net/10962/d1017929
- Description: It is well established that both learning and teaching programming are difficult tasks. Difficulties often occur due to weak mental models and common misconceptions. This study proposes a method of teaching programming that both encourages high-fidelity mental models and attempts to minimise misconceptions in novice programmers, through the use of metaphors and manipulatives. The elements in ActionWorld with which the students interact are realizations of metaphors. By simple example, a variable has a metaphorical representation as a labelled box that can hold a value. The dissertation develops a set of metaphors which have several core requirements: metaphors should avoid causing misconceptions, they need to be high-fidelity so as to avoid failing when used with a new concept, students must be able to relate to them, and finally, they should be usable across multiple educational media. The learning style that ActionWorld supports is one which requires active participation from the student - the system acts as a foundation upon which students are encouraged to build their mental models. This teaching style is achieved by placing the student in the role of code interpreter, the code they need to interpret will not advance until they have demonstrated its meaning via use of the aforementioned metaphors. ActionWorld was developed using an iterative developmental process that consistently improved upon various aspects of the project through a continual evaluation-enhancement cycle. The primary outputs of this project include a unified set of high-fidelity metaphors, a virtual-machine API for use in similar future projects, and two metaphor-testing games. All of the aforementioned deliverables were tested using multiple quality-evaluation criteria, the results of which were consistently positive. ActionWorld and its constituent components contribute to the wide assortment of methods one might use to teach novice programmers.
- Full Text:
- Date Issued: 2015
Developing the marital life course perspective as a conceptual framework for describing and understanding marital life events and marital transitions
- Authors: Rautenbach, John Victor
- Date: 2015
- Subjects: Marriage , Marital status , Married people
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/2991 , vital:20384
- Description: This research seeks to explore the development of the Marital Life Course Perspective as a conceptual framework for describing and understanding marital life events and marital transitions. The study’s orientation is guided by the Life Course Perspective (Glen Elder Jr.) as a theoretical framework and draws on Interpretative Phenomenological Analysis (Jonathan Smith) and Concept Analysis (Walker & Avant) as methodological approaches. One hundred and thirty (130) academic works that use the term marital life course in their texts constituted a literature-dataset for a Concept Analysis (Walker & Avant, 1988; 2011) that tracked the theoretical development of the Marital Life Course Perspective since 1980 (George, 1980, p. 80). The residents of retirement centres and old age homes in East London and Buffalo City (all older than 65 years of age) were invited to share a retrospective history of their relationship experiences, about their multiple marital life events and the marital transitions that shaped their marital life course. The 16 women who participated in the in-depth interviews had all been previously married more than once and were currently single due to divorce or the death of their husbands. This empirical data was analysed using Interpretative Phenomenological Analysis (IPA) as a guide (Smith, Flowers, & Larkin, 2009). After the analysis and synthesis of both datasets the following proposed operational definition of the Marital Life Course Perspective was constructed: The Marital Life Course Perspective is a conceptual framework for describing and understanding marital life events and marital transitions. As a subset of the Life Course Perspective, the Marital Life Course Perspective seeks to understand all stages of the marital experience within their wider social and cultural contexts, which are shaped by the historical dimension of a cohort’s specific time and geographic location. Marital life events include, but are not limited to, marital status changes. An individual may experience multiple marriage life events throughout their life, each with associated role transitions that vary according to their temporality and the individuals whose lives are linked to the marital experience. Well-being and transition outcomes across the marital life course may be promoted or impeded by an interplay of risk and protective factors, and agency-related capacity or resilience.
- Full Text:
- Date Issued: 2015
- Authors: Rautenbach, John Victor
- Date: 2015
- Subjects: Marriage , Marital status , Married people
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/2991 , vital:20384
- Description: This research seeks to explore the development of the Marital Life Course Perspective as a conceptual framework for describing and understanding marital life events and marital transitions. The study’s orientation is guided by the Life Course Perspective (Glen Elder Jr.) as a theoretical framework and draws on Interpretative Phenomenological Analysis (Jonathan Smith) and Concept Analysis (Walker & Avant) as methodological approaches. One hundred and thirty (130) academic works that use the term marital life course in their texts constituted a literature-dataset for a Concept Analysis (Walker & Avant, 1988; 2011) that tracked the theoretical development of the Marital Life Course Perspective since 1980 (George, 1980, p. 80). The residents of retirement centres and old age homes in East London and Buffalo City (all older than 65 years of age) were invited to share a retrospective history of their relationship experiences, about their multiple marital life events and the marital transitions that shaped their marital life course. The 16 women who participated in the in-depth interviews had all been previously married more than once and were currently single due to divorce or the death of their husbands. This empirical data was analysed using Interpretative Phenomenological Analysis (IPA) as a guide (Smith, Flowers, & Larkin, 2009). After the analysis and synthesis of both datasets the following proposed operational definition of the Marital Life Course Perspective was constructed: The Marital Life Course Perspective is a conceptual framework for describing and understanding marital life events and marital transitions. As a subset of the Life Course Perspective, the Marital Life Course Perspective seeks to understand all stages of the marital experience within their wider social and cultural contexts, which are shaped by the historical dimension of a cohort’s specific time and geographic location. Marital life events include, but are not limited to, marital status changes. An individual may experience multiple marriage life events throughout their life, each with associated role transitions that vary according to their temporality and the individuals whose lives are linked to the marital experience. Well-being and transition outcomes across the marital life course may be promoted or impeded by an interplay of risk and protective factors, and agency-related capacity or resilience.
- Full Text:
- Date Issued: 2015
Development and manufacture of sustained release captopril beads
- Authors: Mhaka, Farai Arthur
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54712 , vital:26602
- Description: Hypertension has a high mortality rate in developing countries such as South Africa. Although the prevention and control of hypertension is a health priority, efforts to decrease the global burden of hypertension and improve control over the condition are inadequate. The use of angiotensin converting enzyme (ACE) inhibitors such as captopril (CPT) have been effective for the management of hypertension when used as first line therapy alone or in combination. Commercially available immediate release dosage forms containing 12.5, 25 and 50 mg of CPT are administered two or three times a day to treat hypertension. CPT degrades in aqueous media with the sulfhydryl functional moiety responsible for adverse effects such as hypersensitivity, taste disturbances and/or presenting with a dry hacking cough. CPT has a short elimination half-life of between 1.6 and 1.9 hours, which means that the compound is a suitable candidate for inclusion in sustained release (SR) dosage forms. Manufacturing a SR dosage form of coated beads for twice daily dosing may reduce the incidence and intensity of undesirable adverse effects, improve the stability of CPT and improve patient adherence. A stability indicating reversed-phase high performance liquid chromatographic (RP-HPLC) method was developed and optimised using a central composite design approach. As part of this approach the interactive effects of input factors, viz. pH, methanol (MeOH) content and column temperature on retention time, were investigated to achieve a separation with well-resolved and symmetrical peaks for CPT and salicylic acid. The method was validated using ICH guidelines and was found to be simple, linear, precise, accurate, selective and rapid for the in vitro quantitation of CPT. The method was successfully applied for the analysis of both commercially available and test formulations. Preformulation studies were undertaken to establish the physical and chemical properties of CPT, excipients and dosage forms to ensure the production of stabile and bioavailable products. Powder blends were assessed for flow properties using angle of repose (AOR), and bulk and tapped density, which were subsequently used to calculate Carr’s Index (CI) and the Hausner ratio (HR). The addition of talc resulted in the most powder blends with AOR, CI and HR that were within a range indicative of satisfactory to good flow properties. The use of talc was necessary to ensure that blending prior to wet granulation and extrusion-spheronisation would produce homogenous powders. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FT-IR) were used for the identification and purity of CPT alone and 1:1 binary mixtures with excipients in an effort to establish if CPT was likely to undergo physical and/or chemical modification during production. The DSC thermograms for all CPT-excipient mixtures revealed the presence of a melting endotherm that was wider, occurring at 110.93 °C (Tpeak for pure CPT). The characteristic peaks for specific functional groups were present in the FT-IR spectra for powder mixtures, indicating the absence of incompatibilities. Dialysis studies were used to investigate if the ammonium oleate present in Surelease® E-7-19010 interacted with CPT. The results suggests that an interaction between CPT and Surelease® E-7-19010 during processing of CPT beads was unlikely to occur. Preliminary investigations reveal that Methocel® K100M, Methocel® E4M, Avicel® PH102, Eudragit® RS PO, Surelease® E-7-19010 and talc are compatible with CPT and could be used for the manufacture of SR CPT beads. CPT beads were manufactured using extrusion-spheronisation and coated using a fluidised bed drier fitted with a Wurster insert. The amount of granulating fluid, coating levels, curing time and formulation composition were varied to achieve CPT release with specific criteria to develop a preliminary formulation. The coated beads met all desired quality attributes in respect of micromeritic and flow properties, content uniformity and friability. Response Surface Methodology was used to further optimise the SR CPT formulation. The Plackett-Burman design was used for this process to produce an SR dosage form with desirable quality attributes achieved by altering formulation composition, extrusion-spheronisation variables and coating parameters. ANOVA data revealed significant responses for yield, aspect ratio, sphericity, coating efficiency and cumulative percent CPT released at 2 and 12 hours. Formulations in which the high molecular weight HPMC were used in increased concentrations resulted in the formation of a sticky wet mass and extrudate, resulting in a decrease in yield. The application of a permeable, but insoluble Surelease® coat onto the surface of the beads formed a barrier that complements the activity of the hydrophilic matrix in preventing rapid dissolution and retarding the release of CPT from the beads. The amount of CPT released over 12 hours revealed that increasing the Methocel® K100M content entrapped CPT and retained it more efficiently in the hydrated matrix, resulting in a slow rate of CPT release. In vitro release data were fitted to a number of models in an attempt to elucidate mechanistic aspects of transport processes specific to CPT from the coated bead formulations. The results of fitting data from optimised batches revealed that the goodness of fit based on the adjusted correlation coefficient ranged between 0.953 and 0.976 for the Higuchi model, indicating that diffusion is a predominant factor that controls CPT release from the coated beads. The results of fitting data to the Korsmeyer-Peppas model suggest that the mechanism of CPT release includes transport of the dissolution medium from the vessel reservoir into the core of the bead due to osmotic potential, dissolution of CPT, mass transfer of the dissolved CPT within the core, partitioning between the solution and polymeric film, mass transfer of dissolved CPT through the film to ultimately reach the bulk dissolution fluid. A SR CPT bead formulation that has potential for further development and optimisation for scaled-up production using RSM approaches and Design of Experiments such as CCD or Box-Behnken has been successfully developed and manufactured using extrusion, spheronisation and coating processes. Assessment of all batches of beads manufactured exhibited satisfactory to good flow properties and demonstrated SR profiles over 12 hours that met USP criteria for SR dosage forms.
- Full Text:
- Date Issued: 2015
- Authors: Mhaka, Farai Arthur
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54712 , vital:26602
- Description: Hypertension has a high mortality rate in developing countries such as South Africa. Although the prevention and control of hypertension is a health priority, efforts to decrease the global burden of hypertension and improve control over the condition are inadequate. The use of angiotensin converting enzyme (ACE) inhibitors such as captopril (CPT) have been effective for the management of hypertension when used as first line therapy alone or in combination. Commercially available immediate release dosage forms containing 12.5, 25 and 50 mg of CPT are administered two or three times a day to treat hypertension. CPT degrades in aqueous media with the sulfhydryl functional moiety responsible for adverse effects such as hypersensitivity, taste disturbances and/or presenting with a dry hacking cough. CPT has a short elimination half-life of between 1.6 and 1.9 hours, which means that the compound is a suitable candidate for inclusion in sustained release (SR) dosage forms. Manufacturing a SR dosage form of coated beads for twice daily dosing may reduce the incidence and intensity of undesirable adverse effects, improve the stability of CPT and improve patient adherence. A stability indicating reversed-phase high performance liquid chromatographic (RP-HPLC) method was developed and optimised using a central composite design approach. As part of this approach the interactive effects of input factors, viz. pH, methanol (MeOH) content and column temperature on retention time, were investigated to achieve a separation with well-resolved and symmetrical peaks for CPT and salicylic acid. The method was validated using ICH guidelines and was found to be simple, linear, precise, accurate, selective and rapid for the in vitro quantitation of CPT. The method was successfully applied for the analysis of both commercially available and test formulations. Preformulation studies were undertaken to establish the physical and chemical properties of CPT, excipients and dosage forms to ensure the production of stabile and bioavailable products. Powder blends were assessed for flow properties using angle of repose (AOR), and bulk and tapped density, which were subsequently used to calculate Carr’s Index (CI) and the Hausner ratio (HR). The addition of talc resulted in the most powder blends with AOR, CI and HR that were within a range indicative of satisfactory to good flow properties. The use of talc was necessary to ensure that blending prior to wet granulation and extrusion-spheronisation would produce homogenous powders. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FT-IR) were used for the identification and purity of CPT alone and 1:1 binary mixtures with excipients in an effort to establish if CPT was likely to undergo physical and/or chemical modification during production. The DSC thermograms for all CPT-excipient mixtures revealed the presence of a melting endotherm that was wider, occurring at 110.93 °C (Tpeak for pure CPT). The characteristic peaks for specific functional groups were present in the FT-IR spectra for powder mixtures, indicating the absence of incompatibilities. Dialysis studies were used to investigate if the ammonium oleate present in Surelease® E-7-19010 interacted with CPT. The results suggests that an interaction between CPT and Surelease® E-7-19010 during processing of CPT beads was unlikely to occur. Preliminary investigations reveal that Methocel® K100M, Methocel® E4M, Avicel® PH102, Eudragit® RS PO, Surelease® E-7-19010 and talc are compatible with CPT and could be used for the manufacture of SR CPT beads. CPT beads were manufactured using extrusion-spheronisation and coated using a fluidised bed drier fitted with a Wurster insert. The amount of granulating fluid, coating levels, curing time and formulation composition were varied to achieve CPT release with specific criteria to develop a preliminary formulation. The coated beads met all desired quality attributes in respect of micromeritic and flow properties, content uniformity and friability. Response Surface Methodology was used to further optimise the SR CPT formulation. The Plackett-Burman design was used for this process to produce an SR dosage form with desirable quality attributes achieved by altering formulation composition, extrusion-spheronisation variables and coating parameters. ANOVA data revealed significant responses for yield, aspect ratio, sphericity, coating efficiency and cumulative percent CPT released at 2 and 12 hours. Formulations in which the high molecular weight HPMC were used in increased concentrations resulted in the formation of a sticky wet mass and extrudate, resulting in a decrease in yield. The application of a permeable, but insoluble Surelease® coat onto the surface of the beads formed a barrier that complements the activity of the hydrophilic matrix in preventing rapid dissolution and retarding the release of CPT from the beads. The amount of CPT released over 12 hours revealed that increasing the Methocel® K100M content entrapped CPT and retained it more efficiently in the hydrated matrix, resulting in a slow rate of CPT release. In vitro release data were fitted to a number of models in an attempt to elucidate mechanistic aspects of transport processes specific to CPT from the coated bead formulations. The results of fitting data from optimised batches revealed that the goodness of fit based on the adjusted correlation coefficient ranged between 0.953 and 0.976 for the Higuchi model, indicating that diffusion is a predominant factor that controls CPT release from the coated beads. The results of fitting data to the Korsmeyer-Peppas model suggest that the mechanism of CPT release includes transport of the dissolution medium from the vessel reservoir into the core of the bead due to osmotic potential, dissolution of CPT, mass transfer of the dissolved CPT within the core, partitioning between the solution and polymeric film, mass transfer of dissolved CPT through the film to ultimately reach the bulk dissolution fluid. A SR CPT bead formulation that has potential for further development and optimisation for scaled-up production using RSM approaches and Design of Experiments such as CCD or Box-Behnken has been successfully developed and manufactured using extrusion, spheronisation and coating processes. Assessment of all batches of beads manufactured exhibited satisfactory to good flow properties and demonstrated SR profiles over 12 hours that met USP criteria for SR dosage forms.
- Full Text:
- Date Issued: 2015
Development of high performance computing cluster for evaluation of sequence alignment algorithms
- Authors: Ngxande, Mkhuseli
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11399 , http://hdl.handle.net/10353/d1020163
- Description: As the biological databases are increasing rapidly, there is a challenge for both Biologists and Computer Scientists to develop algorithms and databases to manage the increasing data. There are many algorithms developed to align the sequences stored in biological databases - some take time to process the data while others are inefficient to produce reasonable results. As more data is generated, and time consuming algorithms are developed to handle them, there is a need for specialized computers to handle the computations. Researchers are typically limited by the computational power of their computers. High Performance Computing (HPC) field addresses this challenge and can be used in a cost-effective manner where there is no need for expensive equipment, instead old computers can be used together to form a powerful system. This is the premise of this research, wherein the setup of a low-cost Beowulf cluster is explored, with the subsequent evaluation of its performance for processing sequent alignment algorithms. A mixed method methodology is used in this dissertation, which consists of literature study, theoretical and practise based system. This mixed method methodology also have a proof and concept where the Beowulf cluster is designed and implemented to perform the sequence alignment algorithms and also the performance test. This dissertation firstly gives an overview of sequence alignment algorithms that are already developed and also highlights their timeline. A presentation of the design and implementation of the Beowulf Cluster is highlighted and this is followed by the experiments on the baseline performance of the cluster. A detailed timeline of the sequence alignment algorithms is given and also the comparison between ClustalW-MPI and T-Coffee (Tree-based Consistency Objective Function For alignment Evaluation) algorithm is presented as part of the findings in the research study. The efficiency of the cluster was observed to be 19.8%, this percentage is unexpected because the predicted efficiency is 83.3%, which is found in the theoretical cluster calculator. The theoretical performance of the cluster showed a high performance as compared with the experimental performance, this is attributable to the slow network, which was 100Mbps, low processor speed of 2.50 GHz, and low memory of 2 Gigabytes.
- Full Text:
- Date Issued: 2015
- Authors: Ngxande, Mkhuseli
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11399 , http://hdl.handle.net/10353/d1020163
- Description: As the biological databases are increasing rapidly, there is a challenge for both Biologists and Computer Scientists to develop algorithms and databases to manage the increasing data. There are many algorithms developed to align the sequences stored in biological databases - some take time to process the data while others are inefficient to produce reasonable results. As more data is generated, and time consuming algorithms are developed to handle them, there is a need for specialized computers to handle the computations. Researchers are typically limited by the computational power of their computers. High Performance Computing (HPC) field addresses this challenge and can be used in a cost-effective manner where there is no need for expensive equipment, instead old computers can be used together to form a powerful system. This is the premise of this research, wherein the setup of a low-cost Beowulf cluster is explored, with the subsequent evaluation of its performance for processing sequent alignment algorithms. A mixed method methodology is used in this dissertation, which consists of literature study, theoretical and practise based system. This mixed method methodology also have a proof and concept where the Beowulf cluster is designed and implemented to perform the sequence alignment algorithms and also the performance test. This dissertation firstly gives an overview of sequence alignment algorithms that are already developed and also highlights their timeline. A presentation of the design and implementation of the Beowulf Cluster is highlighted and this is followed by the experiments on the baseline performance of the cluster. A detailed timeline of the sequence alignment algorithms is given and also the comparison between ClustalW-MPI and T-Coffee (Tree-based Consistency Objective Function For alignment Evaluation) algorithm is presented as part of the findings in the research study. The efficiency of the cluster was observed to be 19.8%, this percentage is unexpected because the predicted efficiency is 83.3%, which is found in the theoretical cluster calculator. The theoretical performance of the cluster showed a high performance as compared with the experimental performance, this is attributable to the slow network, which was 100Mbps, low processor speed of 2.50 GHz, and low memory of 2 Gigabytes.
- Full Text:
- Date Issued: 2015
Development role players' knowledge of ecological infrastructure in Eden district, South Africa
- Authors: Crisp, Abigail Gilmour
- Date: 2015
- Subjects: Climatic changes -- South Africa , Environmental management , Coastal engineering
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/8725 , vital:26424
- Description: Coastal disasters have been increasing in intensity and frequency around the world causing loss of life and millions of Rands’ worth of damage to infrastructure. Coastal communities are growing as more people are drawn to urban areas. These people depend on the services the coastal ecosystem provide but through degradation and land use change the supply of services is reduced. The ability of these communities and landscapes to bounce back from disturbance has been severely hampered. As a result communities are looking for ways in which they can protect their lives and their assets and become more resilient. Through development planning structures such as coastal foredunes, that offer a buffering capacity against storm surges, can be used to strengthen the resilience of coastal communities. The type of defences used in communities would be dependent on the knowledge of the decision makers. This study explores the discourses and practices that are present in development processes regarding ecological infrastructure (in its buffering capacity for risk reduction) as an option for adaptation to global environmental change in the coastal areas of Eden District. Qualitative data collection and analysis techniques were used. In-depth interviews were used to collect data, which was transformed into frequency data using content analysis. Descriptive statistics was then applied to the coded frequencies. The interpretation of the data was presented alongside the frequency data, via the descriptive statistics and quotations from interviews. It was determined that role players in development processes are aware of the complexities surrounding coastal social-ecological systems and understand the role foredunes play as ecological infrastructure within this system. Those who lack knowledge are aware of their knowledge gaps. Participants believe the study area is at risk due to human impacts and overall, participants felt that there is a general lack of awareness with regard to issues affecting our coastline, compounded by the absence of an enabling environment brought about by a lack of finances and time.
- Full Text:
- Date Issued: 2015
- Authors: Crisp, Abigail Gilmour
- Date: 2015
- Subjects: Climatic changes -- South Africa , Environmental management , Coastal engineering
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/8725 , vital:26424
- Description: Coastal disasters have been increasing in intensity and frequency around the world causing loss of life and millions of Rands’ worth of damage to infrastructure. Coastal communities are growing as more people are drawn to urban areas. These people depend on the services the coastal ecosystem provide but through degradation and land use change the supply of services is reduced. The ability of these communities and landscapes to bounce back from disturbance has been severely hampered. As a result communities are looking for ways in which they can protect their lives and their assets and become more resilient. Through development planning structures such as coastal foredunes, that offer a buffering capacity against storm surges, can be used to strengthen the resilience of coastal communities. The type of defences used in communities would be dependent on the knowledge of the decision makers. This study explores the discourses and practices that are present in development processes regarding ecological infrastructure (in its buffering capacity for risk reduction) as an option for adaptation to global environmental change in the coastal areas of Eden District. Qualitative data collection and analysis techniques were used. In-depth interviews were used to collect data, which was transformed into frequency data using content analysis. Descriptive statistics was then applied to the coded frequencies. The interpretation of the data was presented alongside the frequency data, via the descriptive statistics and quotations from interviews. It was determined that role players in development processes are aware of the complexities surrounding coastal social-ecological systems and understand the role foredunes play as ecological infrastructure within this system. Those who lack knowledge are aware of their knowledge gaps. Participants believe the study area is at risk due to human impacts and overall, participants felt that there is a general lack of awareness with regard to issues affecting our coastline, compounded by the absence of an enabling environment brought about by a lack of finances and time.
- Full Text:
- Date Issued: 2015
Dialectical critical realism and cultural historical activity theory (CHAT): Exploring and expanding learning processes in sustainable agriculture workplace contexts
- Authors: Mukute, Mutizwa
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/436996 , vital:73322 , ISBN 9781315660899 , https://www.routledge.com/Critical-Realism-Environmental-Learning-and-Social-Ecological-Change/Price-Lotz-Sistka/p/book/9780367597689
- Description: Sustainable agriculture (its learning, practice and development) is becoming increasingly important in Africa and globally be-cause of its potential to reduce social ecological risks while simultaneously enhancing related sustainability and resilience. Against this background, the objectives of the study forming the basis of this chapter were to explore and expand the learn-ing and practice of sustainable agriculture in three research sites in southern Africa. This paper focuses on how the author worked with critical realism to underlabour Cultural Historical Activity Theory (CHAT) to address the research objectives. Us-ing a multiple case study approach, the author worked with 80 farmers, extension workers, sustainable agriculture facilitators and researchers and organic marketers to explore and expand their learning and practice of three kinds of sustainable agricul-ture: permaculture, organic farming and the Machobane Farm-ing System (MFS). In particular the author made use of critical realism’s dialectics, multiple layers of reality and causal expla-nation, double hermeneutics, and modes of inference to deep-en data generation, analysis and use. Working with critical real-ism enabled the study to: (a) pay attention to causal mecha-nisms and power relations; (b) provide explanatory critique; (c) achieve in-depth ‘exploration’ through inductive, abductive and retroductive analysis; and (d) overcome the constructivist limi-tations of CHAT. Critical realism also enabled the mobilization of research participants’ agency and reflexivity to respond to the socio-ecological issues and risks that they were facing. The author concluded that critical realism can be effectively used to underlabour constructivist and epistemological theo-ries for ontological depth; and to help understand and tackle contemporary social ecological issues.
- Full Text:
- Date Issued: 2015
- Authors: Mukute, Mutizwa
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/436996 , vital:73322 , ISBN 9781315660899 , https://www.routledge.com/Critical-Realism-Environmental-Learning-and-Social-Ecological-Change/Price-Lotz-Sistka/p/book/9780367597689
- Description: Sustainable agriculture (its learning, practice and development) is becoming increasingly important in Africa and globally be-cause of its potential to reduce social ecological risks while simultaneously enhancing related sustainability and resilience. Against this background, the objectives of the study forming the basis of this chapter were to explore and expand the learn-ing and practice of sustainable agriculture in three research sites in southern Africa. This paper focuses on how the author worked with critical realism to underlabour Cultural Historical Activity Theory (CHAT) to address the research objectives. Us-ing a multiple case study approach, the author worked with 80 farmers, extension workers, sustainable agriculture facilitators and researchers and organic marketers to explore and expand their learning and practice of three kinds of sustainable agricul-ture: permaculture, organic farming and the Machobane Farm-ing System (MFS). In particular the author made use of critical realism’s dialectics, multiple layers of reality and causal expla-nation, double hermeneutics, and modes of inference to deep-en data generation, analysis and use. Working with critical real-ism enabled the study to: (a) pay attention to causal mecha-nisms and power relations; (b) provide explanatory critique; (c) achieve in-depth ‘exploration’ through inductive, abductive and retroductive analysis; and (d) overcome the constructivist limi-tations of CHAT. Critical realism also enabled the mobilization of research participants’ agency and reflexivity to respond to the socio-ecological issues and risks that they were facing. The author concluded that critical realism can be effectively used to underlabour constructivist and epistemological theo-ries for ontological depth; and to help understand and tackle contemporary social ecological issues.
- Full Text:
- Date Issued: 2015
Die verjaardagvers-ritueel in Breyten Breytenbach se oeuvre
- Authors: Tait, Charles Norman
- Date: 2015
- Subjects: Breytenbach, Breyten -- Poetry , Poets, South African
- Language: Afrikaans
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/5076 , vital:20800
- Description: This study investigates the subgenre of the birthday poem within Breyten Breytenbach’s poetical oeuvre. Throughout the now half a century of his poetic production the writer has repeatedly written poems for himself on his birthday on 16 September of each new year (as well as a smaller number to his wife and close friends) The writing of birthday poems becomes a ritualist poetical act throughout the poet’s life and poetical oeuvre, one that has served many purposes over the years of Breytenbach’s increasingly nomadic existence. This study’s scope spans fifty years of poetical output, starting with the poet’s debut anthology, Die ysterkoei moet sweet (1964), including all the anthologies up to the publication of vyf-en-veertig skemeraandsange uit die eenbeendanser se werkruimte (2014). A small literary history is offered at the outset of the tradition of the birthday poem, based in classical Roman times (Argetsinger,K 1992) and following through to modern times. After describing the reasons for the sometimes challenging task of identifying birthday poems (unmarked by dates, having to rely on inference deduced from the content, and the like), the poems are analyzed with a particular focus on their nature and function within the larger context of the poet’s oeuvre. The research is organized according to the separate phases traceable in Breyten Breytenbach’s oeuvre (Van Vuuren 2011: 46–56), describing the steadily shifting themes and motifs of the subgenre throughout each of the four phases (pre-prison, prison, post-prison and late work phases). It was found that the birthday poems cohere as a subgenre within the oeuvre. Breytenbach’s birthday poems have a distinctive character and certain identifiable qualities (ritualistic characteristics such as reflection on the self within the present, reflection on time past, evaluating the situation and self on the particular birthday. Placed against the specific context in which the poet finds himself, with a poetical and autobiographical way forward implied in the given milieu and context, psychological insights are utilized where applicable, especially in the prison birthday poems and the late work birthday poems. A remarkable new insight gained through this study is the nature of he “reminiscence bump” (Janssen, Haque 2014) which older people experience, and is identified also in Breytenbach’s late work birthday poems. This adds to and refines the understanding of the nature of late work in Breytenbach’s poetical oeuvre. A final insight gained from the research is that description and comprehension of this smaller corpus of birthday poems (roughly thirty identified at present) may also be used as an entry into understanding of the nature of the poet’s large oeuvre (comprising twenty collections of poetry, containing around 1,600 poems between 1964 and 2014), as they represent each stage of development in Breyten Breytenbach’s oeuvre.
- Full Text:
- Date Issued: 2015
- Authors: Tait, Charles Norman
- Date: 2015
- Subjects: Breytenbach, Breyten -- Poetry , Poets, South African
- Language: Afrikaans
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/5076 , vital:20800
- Description: This study investigates the subgenre of the birthday poem within Breyten Breytenbach’s poetical oeuvre. Throughout the now half a century of his poetic production the writer has repeatedly written poems for himself on his birthday on 16 September of each new year (as well as a smaller number to his wife and close friends) The writing of birthday poems becomes a ritualist poetical act throughout the poet’s life and poetical oeuvre, one that has served many purposes over the years of Breytenbach’s increasingly nomadic existence. This study’s scope spans fifty years of poetical output, starting with the poet’s debut anthology, Die ysterkoei moet sweet (1964), including all the anthologies up to the publication of vyf-en-veertig skemeraandsange uit die eenbeendanser se werkruimte (2014). A small literary history is offered at the outset of the tradition of the birthday poem, based in classical Roman times (Argetsinger,K 1992) and following through to modern times. After describing the reasons for the sometimes challenging task of identifying birthday poems (unmarked by dates, having to rely on inference deduced from the content, and the like), the poems are analyzed with a particular focus on their nature and function within the larger context of the poet’s oeuvre. The research is organized according to the separate phases traceable in Breyten Breytenbach’s oeuvre (Van Vuuren 2011: 46–56), describing the steadily shifting themes and motifs of the subgenre throughout each of the four phases (pre-prison, prison, post-prison and late work phases). It was found that the birthday poems cohere as a subgenre within the oeuvre. Breytenbach’s birthday poems have a distinctive character and certain identifiable qualities (ritualistic characteristics such as reflection on the self within the present, reflection on time past, evaluating the situation and self on the particular birthday. Placed against the specific context in which the poet finds himself, with a poetical and autobiographical way forward implied in the given milieu and context, psychological insights are utilized where applicable, especially in the prison birthday poems and the late work birthday poems. A remarkable new insight gained through this study is the nature of he “reminiscence bump” (Janssen, Haque 2014) which older people experience, and is identified also in Breytenbach’s late work birthday poems. This adds to and refines the understanding of the nature of late work in Breytenbach’s poetical oeuvre. A final insight gained from the research is that description and comprehension of this smaller corpus of birthday poems (roughly thirty identified at present) may also be used as an entry into understanding of the nature of the poet’s large oeuvre (comprising twenty collections of poetry, containing around 1,600 poems between 1964 and 2014), as they represent each stage of development in Breyten Breytenbach’s oeuvre.
- Full Text:
- Date Issued: 2015
Diet of coastal filter feeders : impact of factors operating at different scales
- Authors: Puccinelli, Eleonora
- Date: 2015
- Subjects: Benthic animals -- Ecology -- South Africa , Benthic animals -- Nutrition
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5929 , http://hdl.handle.net/10962/d1017807
- Description: Benthic filter feeders have a key functional role in the dynamics of coastal food web as an intermediate trophic level and bioengineers. A wide variety of factors, operating across multiple spatial scales (e.g. hydrographic regime, human activities), can affect the composition of the water column and thus the availability of food for benthic populations. Food availability in turn affects the growth, reproductive rates and survival of benthic organisms, and consequently, can influence the functioning of the entire ecosystem. This study aims to evaluate how various environmental factors may modify the diet of intertidal filter feeders living along the South African coast. Specifically, the effects of biogeography, upwelling, urbanization and freshwater input on the dietary regimes of five species of filter feeders (two mussel and three barnacle species) were investigated using fatty acid (FA) and stable isotope (SI) analyses.Strong interspecific differences were found among the five species considered. However, all species responded to factors operating at large (100s km) and meso (10s- 100s km) scales (i.e. biogeography and upwelling respectively). The barnacles exhibit habitat segregation and showed different FA and SI signatures from each other, while the two mussel species, an invasive and native species that co-occur in the same mussel beds, had partially overlapping diets. Differences in their diets were found only using FA analysis, while their SI signatures differed on only one occasion. This highlights the importance of using the appropriate tool, and ideally combined techniques, to investigate diets.FA and SI signatures of all species considered changed among the three biographical provinces (west, south and east coasts of South Africa) exhibiting similar patterns that reflect the two oceanographic regimes that characterize the coastline: the eutrophic Benguela Current on the west coast and the oligotrophic Agulhas Current on the other two coasts. Upwelling had a significant effect on FA and SI signatures, with stronger effects on the west coast than the south coast. The results indicate that benthic filter feeders at upwelling areas consumed a mix of coastal macroalgal detritus and phytoplankton, which was probably brought onshore during downwelling events. At smaller spatialscales and using repeated sampling, the influence of upwelling on the west coast was found to be pervasive, rather than discrete, so that it may be more appropriate to categorize upwelling by referring to upwelling centres and downstream areas. SI underlined a significant effect of urbanization on the diet of filter feeders with an enrichment in the δ¹⁵N being characteristic of anthropogenic effect. Although a large number of rivers characterize the South African coast, no distinct effect of freshwater input was found for either the SI or FA signatures of the filter feeders. This contrasts with earlier work on demersal species and suggests that freshwater input does not significantly affect food availability for intertidal filter feeders, and that other factors (e.g. hydrogeography) are more important in determining the diet of these populations. These results highlight that environmental and anthropogenic factors operating at different spatial and temporal scales have a profound effect on benthic ecosystems, and that they control the relationship between primary production and primary consumers in coastal areas. Above all, this work highlights the importance of understanding the spatial and temporal scales at which different factors affect feeding regimes, and their critical role in coastal food webs.
- Full Text:
- Date Issued: 2015
- Authors: Puccinelli, Eleonora
- Date: 2015
- Subjects: Benthic animals -- Ecology -- South Africa , Benthic animals -- Nutrition
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5929 , http://hdl.handle.net/10962/d1017807
- Description: Benthic filter feeders have a key functional role in the dynamics of coastal food web as an intermediate trophic level and bioengineers. A wide variety of factors, operating across multiple spatial scales (e.g. hydrographic regime, human activities), can affect the composition of the water column and thus the availability of food for benthic populations. Food availability in turn affects the growth, reproductive rates and survival of benthic organisms, and consequently, can influence the functioning of the entire ecosystem. This study aims to evaluate how various environmental factors may modify the diet of intertidal filter feeders living along the South African coast. Specifically, the effects of biogeography, upwelling, urbanization and freshwater input on the dietary regimes of five species of filter feeders (two mussel and three barnacle species) were investigated using fatty acid (FA) and stable isotope (SI) analyses.Strong interspecific differences were found among the five species considered. However, all species responded to factors operating at large (100s km) and meso (10s- 100s km) scales (i.e. biogeography and upwelling respectively). The barnacles exhibit habitat segregation and showed different FA and SI signatures from each other, while the two mussel species, an invasive and native species that co-occur in the same mussel beds, had partially overlapping diets. Differences in their diets were found only using FA analysis, while their SI signatures differed on only one occasion. This highlights the importance of using the appropriate tool, and ideally combined techniques, to investigate diets.FA and SI signatures of all species considered changed among the three biographical provinces (west, south and east coasts of South Africa) exhibiting similar patterns that reflect the two oceanographic regimes that characterize the coastline: the eutrophic Benguela Current on the west coast and the oligotrophic Agulhas Current on the other two coasts. Upwelling had a significant effect on FA and SI signatures, with stronger effects on the west coast than the south coast. The results indicate that benthic filter feeders at upwelling areas consumed a mix of coastal macroalgal detritus and phytoplankton, which was probably brought onshore during downwelling events. At smaller spatialscales and using repeated sampling, the influence of upwelling on the west coast was found to be pervasive, rather than discrete, so that it may be more appropriate to categorize upwelling by referring to upwelling centres and downstream areas. SI underlined a significant effect of urbanization on the diet of filter feeders with an enrichment in the δ¹⁵N being characteristic of anthropogenic effect. Although a large number of rivers characterize the South African coast, no distinct effect of freshwater input was found for either the SI or FA signatures of the filter feeders. This contrasts with earlier work on demersal species and suggests that freshwater input does not significantly affect food availability for intertidal filter feeders, and that other factors (e.g. hydrogeography) are more important in determining the diet of these populations. These results highlight that environmental and anthropogenic factors operating at different spatial and temporal scales have a profound effect on benthic ecosystems, and that they control the relationship between primary production and primary consumers in coastal areas. Above all, this work highlights the importance of understanding the spatial and temporal scales at which different factors affect feeding regimes, and their critical role in coastal food webs.
- Full Text:
- Date Issued: 2015
Dishing up meat
- Unnamed
- Authors: Unnamed
- Date: 2015
- Subjects: UNCATALOGUED
- Type: Video
- Identifier: http://hdl.handle.net/10962/303576 , vital:58349 , KHV-263
- Description: Dishing up meat outdoors outdoors , Use of this resource is governed by the terms and conditions of the Creative Commons "Attribution-NonCommercial-ShareAlike" License (http://creativecommons.org/licenses/by-nc-sa/2.0/) (NEVER CAHNGE THIS FIELD)
- Full Text: false
- Date Issued: 2015
- Authors: Unnamed
- Date: 2015
- Subjects: UNCATALOGUED
- Type: Video
- Identifier: http://hdl.handle.net/10962/303576 , vital:58349 , KHV-263
- Description: Dishing up meat outdoors outdoors , Use of this resource is governed by the terms and conditions of the Creative Commons "Attribution-NonCommercial-ShareAlike" License (http://creativecommons.org/licenses/by-nc-sa/2.0/) (NEVER CAHNGE THIS FIELD)
- Full Text: false
- Date Issued: 2015
Dismissal of members of the South African Police Service for criminal convictions
- Authors: Deysel, Petrus Gerhardus
- Date: 2015
- Subjects: Employees -- Dismissal of -- South Africa , Police corruption -- South Africa , Judgments, Criminal -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10948/6084 , vital:21037
- Description: The dawn of democracy failed to bring legitimacy to the Police Service. Public and political debate seriously lambasted the Police Service for criminal offences committed on and off duty by police officials which pertained to the infringement on the individual rights regarding personal safety and the right to own property. The outcry against criminal offences by police officials forced the Police Service to deal decisively with criminality in the Police Service by means of fitness boards. While the government and public approved of the attempts to rid the Police Service of criminality it was met with union resistance in the Eastern Cape and defeat in the Labour Court. Different legislation, internal arrangements and case law were observed in this study. The purpose was to determine the strength or weaknesses if any of the applicable legislation and internal arrangements which contributed to a finding against the Police Service in the Labour Court.
- Full Text:
- Date Issued: 2015
- Authors: Deysel, Petrus Gerhardus
- Date: 2015
- Subjects: Employees -- Dismissal of -- South Africa , Police corruption -- South Africa , Judgments, Criminal -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10948/6084 , vital:21037
- Description: The dawn of democracy failed to bring legitimacy to the Police Service. Public and political debate seriously lambasted the Police Service for criminal offences committed on and off duty by police officials which pertained to the infringement on the individual rights regarding personal safety and the right to own property. The outcry against criminal offences by police officials forced the Police Service to deal decisively with criminality in the Police Service by means of fitness boards. While the government and public approved of the attempts to rid the Police Service of criminality it was met with union resistance in the Eastern Cape and defeat in the Labour Court. Different legislation, internal arrangements and case law were observed in this study. The purpose was to determine the strength or weaknesses if any of the applicable legislation and internal arrangements which contributed to a finding against the Police Service in the Labour Court.
- Full Text:
- Date Issued: 2015
Dispersal of sterile false codling moth, Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), for a sterile insect technique programme on citrus
- Authors: Wagenaar, Gideon Daniel
- Date: 2015
- Subjects: Cryptophlebia leucotreta , Insect pests -- Control -- South Africa , Citrus -- Diseases and pests -- Control -- South Africa , Insect sterilization
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/4977 , vital:20774
- Description: The false codling moth (FCM), Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), is an important pest of citrus in South Africa and challenging to manage due to its inconspicuous nature. An effective method currently being employed for the area-wide suppression of the FCM is the Sterile Insect Technique (SIT) and the effective dispersal of sterile moths is very important for success with SIT. This study was conducted in the Addo area of the Sundays River Valley (Eastern Cape) where the programme is commercially used. In this study, sterile male moths were released in different orchards on a citrus farm, and in nearby veld at different times of the year, and their dispersal was monitored through the use of pheromone traps. Various climatic factors were monitored. This provided insight into the local dispersal of sterile male FCM adults in response to abiotic cues (particularly climatic factors). The movement of the FCM in four citrus cultivars, namely lemons, navel and Valencia oranges and mandarins and in the nearby veld (open field), was determined at six different stages of the year. Results clearly indicated that sterile FCM movement is concentrated within citrus orchards, as very few moths were trapped beyond 30 m from the release point, particularly in navel and Valencia orchards. Of the climatic factors measured, minimum and maximum temperatures had the most significant influence on FCM dispersal, and based on the results, various recommendations are made for the releases of sterile FCM in an area-wide SIT management programmes on citrus. A better understanding of the dispersal capabilities of the FCM in an agricultural system, under different conditions and at different times of the year, is invaluable not only in improving release strategies in an SIT programme but in planning future control strategies against the FCM.
- Full Text:
- Date Issued: 2015
- Authors: Wagenaar, Gideon Daniel
- Date: 2015
- Subjects: Cryptophlebia leucotreta , Insect pests -- Control -- South Africa , Citrus -- Diseases and pests -- Control -- South Africa , Insect sterilization
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/4977 , vital:20774
- Description: The false codling moth (FCM), Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), is an important pest of citrus in South Africa and challenging to manage due to its inconspicuous nature. An effective method currently being employed for the area-wide suppression of the FCM is the Sterile Insect Technique (SIT) and the effective dispersal of sterile moths is very important for success with SIT. This study was conducted in the Addo area of the Sundays River Valley (Eastern Cape) where the programme is commercially used. In this study, sterile male moths were released in different orchards on a citrus farm, and in nearby veld at different times of the year, and their dispersal was monitored through the use of pheromone traps. Various climatic factors were monitored. This provided insight into the local dispersal of sterile male FCM adults in response to abiotic cues (particularly climatic factors). The movement of the FCM in four citrus cultivars, namely lemons, navel and Valencia oranges and mandarins and in the nearby veld (open field), was determined at six different stages of the year. Results clearly indicated that sterile FCM movement is concentrated within citrus orchards, as very few moths were trapped beyond 30 m from the release point, particularly in navel and Valencia orchards. Of the climatic factors measured, minimum and maximum temperatures had the most significant influence on FCM dispersal, and based on the results, various recommendations are made for the releases of sterile FCM in an area-wide SIT management programmes on citrus. A better understanding of the dispersal capabilities of the FCM in an agricultural system, under different conditions and at different times of the year, is invaluable not only in improving release strategies in an SIT programme but in planning future control strategies against the FCM.
- Full Text:
- Date Issued: 2015
Diversity in Human Sexuality: Implications for Policy in Africa
- Authors: Dugmore, Harry
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/453379 , vital:75249 , ISBN , https://doi.org/10.17159/assaf/0022
- Description: Although two-thirds of countries in the world no longer outlaw lesbian, gay, bisexual, transgender and intersex (LGBTI) relationships, same-sex relationships are still illegal in 76 countries. In the recent past, new laws have been passed in Russia, India, Nigeria, Burundi, Cameroon and Uganda and are being contemplated in other countries to further prohibit same-sex relationships or the so-called ‘promotion of homosexuality’. There is evidence that such new laws precipitate negative consequences not just for LGBTI persons and communities, but also for societies as a whole, including the rapid reversal of key public health gains, particularly in terms of HIV and AIDS and other sexual health programmes, increases in levels of social violence, some evidence of reduced economic growth, and the diversion of attention from sexual and other violence against women and children.
- Full Text:
- Date Issued: 2015
- Authors: Dugmore, Harry
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/453379 , vital:75249 , ISBN , https://doi.org/10.17159/assaf/0022
- Description: Although two-thirds of countries in the world no longer outlaw lesbian, gay, bisexual, transgender and intersex (LGBTI) relationships, same-sex relationships are still illegal in 76 countries. In the recent past, new laws have been passed in Russia, India, Nigeria, Burundi, Cameroon and Uganda and are being contemplated in other countries to further prohibit same-sex relationships or the so-called ‘promotion of homosexuality’. There is evidence that such new laws precipitate negative consequences not just for LGBTI persons and communities, but also for societies as a whole, including the rapid reversal of key public health gains, particularly in terms of HIV and AIDS and other sexual health programmes, increases in levels of social violence, some evidence of reduced economic growth, and the diversion of attention from sexual and other violence against women and children.
- Full Text:
- Date Issued: 2015