The implementation and evaluation of a service-learning component in a second year undergraduate organic chemistry course
- Authors: Abel, Sarah Ruth
- Date: 2011 , 2010-10-03
- Subjects: Chemistry, Organic -- Study and teaching (Higher) -- South Africa , Action research in education -- South Africa , Experiential learning -- South Africa , Service learning -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4393 , http://hdl.handle.net/10962/d1006008 , Chemistry, Organic -- Study and teaching (Higher) -- South Africa , Action research in education -- South Africa , Experiential learning -- South Africa , Service learning -- South Africa
- Description: The project describes the action research implementation, and evaluation of learning, of a service-learning component in a second year undergraduate organic chemistry course. The research aims to explore the learning that takes place in a service-learning context while utilizing an action research methodology within the critical theory paradigm. This occurs in response to the world-wide call for Higher Education to produce people with civic competencies and responsiveness to the society in which they live (Boyer 1996). Educating young Chemists to see the importance of their knowledge and their responsibilities in society is an important pedagogical step in the effort to cross boundaries and make connections between people communities (Eyler and Giles 1999). The goal of this project was to explore and categorize the learning that takes place in a service-learning context and discover how these areas of learning impact the awareness of the parties involved with regard to the discipline of chemistry as well as social issues. The project makes use of Kolb‘s (1984) Experiential Learning Theory, and Eyler and Giles‘ (1999) categories of learning in service-learning and results indicate that service-learning can be a powerful pedagogical tool to increase learning in chemistry as well as in the areas of critical thinking, personal and social development, reflection and citizenship. Students‘ perceptions of themselves, their discipline and their responsibility to society were transformed by their experience of service-learning in their undergraduate chemistry course.
- Full Text:
- Date Issued: 2011
- Authors: Abel, Sarah Ruth
- Date: 2011 , 2010-10-03
- Subjects: Chemistry, Organic -- Study and teaching (Higher) -- South Africa , Action research in education -- South Africa , Experiential learning -- South Africa , Service learning -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4393 , http://hdl.handle.net/10962/d1006008 , Chemistry, Organic -- Study and teaching (Higher) -- South Africa , Action research in education -- South Africa , Experiential learning -- South Africa , Service learning -- South Africa
- Description: The project describes the action research implementation, and evaluation of learning, of a service-learning component in a second year undergraduate organic chemistry course. The research aims to explore the learning that takes place in a service-learning context while utilizing an action research methodology within the critical theory paradigm. This occurs in response to the world-wide call for Higher Education to produce people with civic competencies and responsiveness to the society in which they live (Boyer 1996). Educating young Chemists to see the importance of their knowledge and their responsibilities in society is an important pedagogical step in the effort to cross boundaries and make connections between people communities (Eyler and Giles 1999). The goal of this project was to explore and categorize the learning that takes place in a service-learning context and discover how these areas of learning impact the awareness of the parties involved with regard to the discipline of chemistry as well as social issues. The project makes use of Kolb‘s (1984) Experiential Learning Theory, and Eyler and Giles‘ (1999) categories of learning in service-learning and results indicate that service-learning can be a powerful pedagogical tool to increase learning in chemistry as well as in the areas of critical thinking, personal and social development, reflection and citizenship. Students‘ perceptions of themselves, their discipline and their responsibility to society were transformed by their experience of service-learning in their undergraduate chemistry course.
- Full Text:
- Date Issued: 2011
Internal auditors perceptions of the impact of control elements on internal control systems
- Authors: Ackerman, Christo
- Date: 2011
- Subjects: Auditing, Internal , Financial statements , Controllership
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8952 , http://hdl.handle.net/10948/d1008158 , Auditing, Internal , Financial statements , Controllership
- Description: The objective of this research report was to determine which internal controls are perceived, by internal auditors, to be contributing to the effectiveness of an internal control structure. The Committee for Sponsoring Organisations (COSO) integrated internal control framework was used as a basis for the questionnaire construction and respondents were asked to rate the perceived control effectiveness of each of the components of internal control. Descriptive statistics were used to analyse the basic meaning of the data. The questionnaire was completed by following a Uniform Resource Locator (URL) which was sent to two internal auditors in audit firms. Thirty one responses were obtained; all the respondents have experience in the evaluation and assessment of internal control systems. This research showed that control elements as outlined in COSOs integrated internal control framework, if implemented, could contribute to the effectiveness of the internal control system.
- Full Text:
- Date Issued: 2011
- Authors: Ackerman, Christo
- Date: 2011
- Subjects: Auditing, Internal , Financial statements , Controllership
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8952 , http://hdl.handle.net/10948/d1008158 , Auditing, Internal , Financial statements , Controllership
- Description: The objective of this research report was to determine which internal controls are perceived, by internal auditors, to be contributing to the effectiveness of an internal control structure. The Committee for Sponsoring Organisations (COSO) integrated internal control framework was used as a basis for the questionnaire construction and respondents were asked to rate the perceived control effectiveness of each of the components of internal control. Descriptive statistics were used to analyse the basic meaning of the data. The questionnaire was completed by following a Uniform Resource Locator (URL) which was sent to two internal auditors in audit firms. Thirty one responses were obtained; all the respondents have experience in the evaluation and assessment of internal control systems. This research showed that control elements as outlined in COSOs integrated internal control framework, if implemented, could contribute to the effectiveness of the internal control system.
- Full Text:
- Date Issued: 2011
The education sector as an essential service
- Authors: Adams, Anton John
- Date: 2011
- Subjects: Educational law and legislation -- South Africa , Teachers -- Legal status, laws, etc. -- South Africa , Right to education -- Law and legislation -- South Africa , Basic education -- South Africa , Human rights -- Study and teaching
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10188 , http://hdl.handle.net/10948/1573 , Educational law and legislation -- South Africa , Teachers -- Legal status, laws, etc. -- South Africa , Right to education -- Law and legislation -- South Africa , Basic education -- South Africa , Human rights -- Study and teaching
- Description: Because of the impact of teacher strikes on education there has been a call to declare the teacher‟s profession an essential service and thus prohibit them from striking. This call was made by the Democratic Alliance (DA). The Democratic Alliance arguments in their application to the Essential Services Committee was based on the fact that education in South Africa is in a crisis and the life-altering inconvenience this caused for children. The combined teacher unions in the Education Labour Relations Council (ELRC) expressed their concerns over the DA‟s call for education to be declared an Essential Service. The Bill of Rights grants every employee the fundamental right to strike. This is an absolute and should always be exercised under certain controlled conditions, as stipulated by the Labour Relations Act 66 of 1995. Convention 87 of the International Labour Organising (ILO) recognises the right of trade unions, as an organisation of workers set up to further and defend their interest (Article 10), to formulate their programs and organise their activities (Article 3); this means that unions have the right to negotiate with employers and to express their views on economic and social issues affecting the occupational interest of their members. This constitutes the position that the right to strike is one of the legitimate and indeed essential means available to workers for furthering and defending their occupational interest. Balanced against the right of every teacher to strike is the right of everyone to have a basic education as set out in section 29 of the Constitution. In terms of section 29(1)(a) everyone has a right, enforceable against the state, to basic education. This creates a strong positive right. Aspects of the right to education are found in human rights treaties and declarations. This right to education is contained in article 26 of the Universal Declaration of Human Rights (1948) which states that “everyone has the right to education”. The International Covenant of Economic, Social and Cultural v Rights of 1966 covers the right to education comprehensively, especially article 13 and 14. In 1989 the Convention on the Rights of the Child further confirmed this right. The right to a basic education is further enhanced by section 28(2) of the Constitution “(a) child‟s best interest is of paramount importance in every matter concerning the child”. It is significant to note that in 2007 the Constitutional Court elevated the “best interest” principle to a right. This implies that the best interest of the child would be the decisive factor in each matter that affects the child. In deciding to declare the teaching profession as an essential service constitutional rights must be balanced. These are the right to strike, the right to a basic education and the best interest of the child principle.
- Full Text:
- Date Issued: 2011
- Authors: Adams, Anton John
- Date: 2011
- Subjects: Educational law and legislation -- South Africa , Teachers -- Legal status, laws, etc. -- South Africa , Right to education -- Law and legislation -- South Africa , Basic education -- South Africa , Human rights -- Study and teaching
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10188 , http://hdl.handle.net/10948/1573 , Educational law and legislation -- South Africa , Teachers -- Legal status, laws, etc. -- South Africa , Right to education -- Law and legislation -- South Africa , Basic education -- South Africa , Human rights -- Study and teaching
- Description: Because of the impact of teacher strikes on education there has been a call to declare the teacher‟s profession an essential service and thus prohibit them from striking. This call was made by the Democratic Alliance (DA). The Democratic Alliance arguments in their application to the Essential Services Committee was based on the fact that education in South Africa is in a crisis and the life-altering inconvenience this caused for children. The combined teacher unions in the Education Labour Relations Council (ELRC) expressed their concerns over the DA‟s call for education to be declared an Essential Service. The Bill of Rights grants every employee the fundamental right to strike. This is an absolute and should always be exercised under certain controlled conditions, as stipulated by the Labour Relations Act 66 of 1995. Convention 87 of the International Labour Organising (ILO) recognises the right of trade unions, as an organisation of workers set up to further and defend their interest (Article 10), to formulate their programs and organise their activities (Article 3); this means that unions have the right to negotiate with employers and to express their views on economic and social issues affecting the occupational interest of their members. This constitutes the position that the right to strike is one of the legitimate and indeed essential means available to workers for furthering and defending their occupational interest. Balanced against the right of every teacher to strike is the right of everyone to have a basic education as set out in section 29 of the Constitution. In terms of section 29(1)(a) everyone has a right, enforceable against the state, to basic education. This creates a strong positive right. Aspects of the right to education are found in human rights treaties and declarations. This right to education is contained in article 26 of the Universal Declaration of Human Rights (1948) which states that “everyone has the right to education”. The International Covenant of Economic, Social and Cultural v Rights of 1966 covers the right to education comprehensively, especially article 13 and 14. In 1989 the Convention on the Rights of the Child further confirmed this right. The right to a basic education is further enhanced by section 28(2) of the Constitution “(a) child‟s best interest is of paramount importance in every matter concerning the child”. It is significant to note that in 2007 the Constitutional Court elevated the “best interest” principle to a right. This implies that the best interest of the child would be the decisive factor in each matter that affects the child. In deciding to declare the teaching profession as an essential service constitutional rights must be balanced. These are the right to strike, the right to a basic education and the best interest of the child principle.
- Full Text:
- Date Issued: 2011
An investigation of the attitudes of South African Police Service management with respect to the viability of computer-assisted training in the Eastern Cape Province
- Authors: Adams, Leinadu
- Date: 2011
- Subjects: Education -- South Africa -- Data processing , Education -- Computer-assisted instruction , Information technology -- Study and teaching -- South Africa , Police training -- South Africa , Police -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:8190 , http://hdl.handle.net/10948/1410 , Education -- South Africa -- Data processing , Education -- Computer-assisted instruction , Information technology -- Study and teaching -- South Africa , Police training -- South Africa , Police -- South Africa -- Attitudes
- Description: The South African Police Service (SAPS) as a constituent part of the public service was established to deliver a specific category of services to the public. These services have to conform to requirements that are prescribed by various legislative provisions to promote effective and efficient delivery of public services. The implications of these provisions that are pursued by the study firstly, refer to the emphasis of government on the enhancement of public service delivery, with due consideration given to cost effectiveness and efficiency. Secondly, it refers to government's realisation of the important impact of education, development and training (EDT) on the competency of public service officials with an emphasis on the utilisation of information technology to enhance the effectiveness of EDT. Consequently, the study explores the viability of the utilisation of information technology as a measure to assist EDT interventions within the SAPS of the Eastern Cape Province to equip members of the institution to better fulfil their functions and duties. In this respect the study commenced to ascertain the levels of computer literacy of role-players, access to the appropriate facilities and what the general attitude in the organisation would be towards the utilisation of such an intervention. It was found that the computer literacy levels of role-players may be perceived as a problematic issue in this regard. However, access to suitable facilities was found to be more than sufficient for this intention. Furthermore, role-players agreed that information technology could be optimally applied in the EC SAPS for the mentioned use, thereby portraying an optimistic attitude towards the use thereof to harmonise EDT in the SAPS. The aim of the study has been to develop a model that will incorporate the use of information technology, given the strengths and weaknesses of the SAPS to enhance EDT and learning in the organization.
- Full Text:
- Date Issued: 2011
- Authors: Adams, Leinadu
- Date: 2011
- Subjects: Education -- South Africa -- Data processing , Education -- Computer-assisted instruction , Information technology -- Study and teaching -- South Africa , Police training -- South Africa , Police -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:8190 , http://hdl.handle.net/10948/1410 , Education -- South Africa -- Data processing , Education -- Computer-assisted instruction , Information technology -- Study and teaching -- South Africa , Police training -- South Africa , Police -- South Africa -- Attitudes
- Description: The South African Police Service (SAPS) as a constituent part of the public service was established to deliver a specific category of services to the public. These services have to conform to requirements that are prescribed by various legislative provisions to promote effective and efficient delivery of public services. The implications of these provisions that are pursued by the study firstly, refer to the emphasis of government on the enhancement of public service delivery, with due consideration given to cost effectiveness and efficiency. Secondly, it refers to government's realisation of the important impact of education, development and training (EDT) on the competency of public service officials with an emphasis on the utilisation of information technology to enhance the effectiveness of EDT. Consequently, the study explores the viability of the utilisation of information technology as a measure to assist EDT interventions within the SAPS of the Eastern Cape Province to equip members of the institution to better fulfil their functions and duties. In this respect the study commenced to ascertain the levels of computer literacy of role-players, access to the appropriate facilities and what the general attitude in the organisation would be towards the utilisation of such an intervention. It was found that the computer literacy levels of role-players may be perceived as a problematic issue in this regard. However, access to suitable facilities was found to be more than sufficient for this intention. Furthermore, role-players agreed that information technology could be optimally applied in the EC SAPS for the mentioned use, thereby portraying an optimistic attitude towards the use thereof to harmonise EDT in the SAPS. The aim of the study has been to develop a model that will incorporate the use of information technology, given the strengths and weaknesses of the SAPS to enhance EDT and learning in the organization.
- Full Text:
- Date Issued: 2011
A study of a class of invariant optimal control problems on the Euclidean group SE(2)
- Authors: Adams, Ross Montague
- Date: 2011
- Subjects: Matrix groups Lie groups Extremal problems (Mathematics) Maximum principles (Mathematics) Hamilton-Jacobi equations Lyapunov stability
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5420 , http://hdl.handle.net/10962/d1006060
- Description: The aim of this thesis is to study a class of left-invariant optimal control problems on the matrix Lie group SE(2). We classify, under detached feedback equivalence, all controllable (left-invariant) control affine systems on SE(2). This result produces six types of control affine systems on SE(2). Hence, we study six associated left-invariant optimal control problems on SE(2). A left-invariant optimal control problem consists of minimizing a cost functional over the trajectory-control pairs of a left-invariant control system subject to appropriate boundary conditions. Each control problem is lifted from SE(2) to T*SE(2) ≅ SE(2) x se (2)*and then reduced to a problem on se (2)*. The maximum principle is used to obtain the optimal control and Hamiltonian corresponding to the normal extremals. Then we derive the (reduced) extremal equations on se (2)*. These equations are explicitly integrated by trigonometric and Jacobi elliptic functions. Finally, we fully classify, under Lyapunov stability, the equilibrium states of the normal extremal equations for each of the six types under consideration.
- Full Text:
- Date Issued: 2011
- Authors: Adams, Ross Montague
- Date: 2011
- Subjects: Matrix groups Lie groups Extremal problems (Mathematics) Maximum principles (Mathematics) Hamilton-Jacobi equations Lyapunov stability
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5420 , http://hdl.handle.net/10962/d1006060
- Description: The aim of this thesis is to study a class of left-invariant optimal control problems on the matrix Lie group SE(2). We classify, under detached feedback equivalence, all controllable (left-invariant) control affine systems on SE(2). This result produces six types of control affine systems on SE(2). Hence, we study six associated left-invariant optimal control problems on SE(2). A left-invariant optimal control problem consists of minimizing a cost functional over the trajectory-control pairs of a left-invariant control system subject to appropriate boundary conditions. Each control problem is lifted from SE(2) to T*SE(2) ≅ SE(2) x se (2)*and then reduced to a problem on se (2)*. The maximum principle is used to obtain the optimal control and Hamiltonian corresponding to the normal extremals. Then we derive the (reduced) extremal equations on se (2)*. These equations are explicitly integrated by trigonometric and Jacobi elliptic functions. Finally, we fully classify, under Lyapunov stability, the equilibrium states of the normal extremal equations for each of the six types under consideration.
- Full Text:
- Date Issued: 2011
Enhancing the role of the Kaizen suggestion tool in South African lean automotive companies of the Eastern Cape
- Authors: Adedeji, Adeyemi Charles
- Date: 2011
- Subjects: Lean manufacturing , Manufacturing processes , Production management -- Mathematical models
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:8644 , http://hdl.handle.net/10948/d1008157 , Lean manufacturing , Manufacturing processes , Production management -- Mathematical models
- Description: The Toyota manufacturing system, aptly referred to as Lean manufacturing, has received a reasonable appreciation and awareness over the past decade in South African industry. This production phenomenon constitutes an organizational culture that encourages world-class production success through the liberation of factory resources, while employees are empowered and encouraged to contribute ideas for the improvement of processes and products. However, despite lean awareness and the crucial role of employee participation in the suggestion of ideas in world-class organizations, the performance level of lean manufacturing in South African industry is largely devoid of the Kaizen suggestion tool, particularly in the automotive companies of the Eastern Cape. The aim of this research was to proffer appropriate recommendations, improved awareness, understanding and practice for the improvement of the Kaizen suggestion principle in the automotive companies of the Eastern Cape. The research primarily focused on the ‘management/employees’ paradigm within the organisational context. The methodology employed in the study included a thorough review of the relevant literature and a questionnaire, which was developed and administered to both the management and employees of the thirty automotive components suppliers in Eastern Cape. The target companies constituted the units of analyses and therefore provided the opportunity for a detailed investigation of the links between management and employees as well as a submission of ideas for operational and organisational processes as established in the literature review. Epistemologically, the research is objectivist and paradigmically, positivist. However, some qualitative aspects of the data were relevant to the study and, therefore, were used in a complementary manner. The case approach utilized mixed methods by applying a range of data collection techniques and evidence from multiple sources while the sampling technique was sequential, involving both purposive and stratified random sampling. The study reveals the apparent lack of a systematic mechanism for the practice and administration of the Kaizen suggestion tools in most Eastern Cape automotive companies. This demerit is found to have negatively affected maximum employee participation and involvement in organizational decision making within the Province. The study has established a basic level of awareness and understanding among employees / employers relations that the Kaizen suggestion scheme is a vital tool for delivering strategic objectives in the management of decision making and organizational growth. The study strongly advocates the inclusion of employee suggestion systems as part of the organizational process.
- Full Text:
- Date Issued: 2011
- Authors: Adedeji, Adeyemi Charles
- Date: 2011
- Subjects: Lean manufacturing , Manufacturing processes , Production management -- Mathematical models
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:8644 , http://hdl.handle.net/10948/d1008157 , Lean manufacturing , Manufacturing processes , Production management -- Mathematical models
- Description: The Toyota manufacturing system, aptly referred to as Lean manufacturing, has received a reasonable appreciation and awareness over the past decade in South African industry. This production phenomenon constitutes an organizational culture that encourages world-class production success through the liberation of factory resources, while employees are empowered and encouraged to contribute ideas for the improvement of processes and products. However, despite lean awareness and the crucial role of employee participation in the suggestion of ideas in world-class organizations, the performance level of lean manufacturing in South African industry is largely devoid of the Kaizen suggestion tool, particularly in the automotive companies of the Eastern Cape. The aim of this research was to proffer appropriate recommendations, improved awareness, understanding and practice for the improvement of the Kaizen suggestion principle in the automotive companies of the Eastern Cape. The research primarily focused on the ‘management/employees’ paradigm within the organisational context. The methodology employed in the study included a thorough review of the relevant literature and a questionnaire, which was developed and administered to both the management and employees of the thirty automotive components suppliers in Eastern Cape. The target companies constituted the units of analyses and therefore provided the opportunity for a detailed investigation of the links between management and employees as well as a submission of ideas for operational and organisational processes as established in the literature review. Epistemologically, the research is objectivist and paradigmically, positivist. However, some qualitative aspects of the data were relevant to the study and, therefore, were used in a complementary manner. The case approach utilized mixed methods by applying a range of data collection techniques and evidence from multiple sources while the sampling technique was sequential, involving both purposive and stratified random sampling. The study reveals the apparent lack of a systematic mechanism for the practice and administration of the Kaizen suggestion tools in most Eastern Cape automotive companies. This demerit is found to have negatively affected maximum employee participation and involvement in organizational decision making within the Province. The study has established a basic level of awareness and understanding among employees / employers relations that the Kaizen suggestion scheme is a vital tool for delivering strategic objectives in the management of decision making and organizational growth. The study strongly advocates the inclusion of employee suggestion systems as part of the organizational process.
- Full Text:
- Date Issued: 2011
Marine anti-malarial isonitriles : a synthetic and computational study
- Authors: Adendorff, Matthew Ralph
- Date: 2011 , 2010-05-17
- Subjects: Isocyanides , Isocyanates , Marine pharmacology , Antimalarials , Antimalarials -- Development , Drug development
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4398 , http://hdl.handle.net/10962/d1006674 , Isocyanides , Isocyanates , Marine pharmacology , Antimalarials , Antimalarials -- Development , Drug development
- Description: The development of Plasmodium falciparum malarial resistance to the current armoury of anti-malarial drugs requires the development of new treatments to help combat this disease. The marine environment is a well established source of potential pharmaceuticals. Of interest to us are isonitrile, isocyanate and isothiocyanate compounds isolated from marine sponges and molluscs which have exhibited nano-molar anti-plasmodial activities. Through quantitative structure-activity relation studies (QSAR), a literature precedent exists for a pseudoreceptor model from which a pharmacophore for the design of novel anti-malarial agents was proposed. The current theory suggests that these marine compounds exert their inhibitory action through interfering with the heme detoxification pathway in P. falciparum. We propose that the computational methods used to draw detailed conclusions about the mode of action of these marine compounds were inadequate. This thesis addresses this problem using contemporary computational methodologies and seeks to propose a more robust method for the rational design of new anti-malarial drug compounds that inhibit heme polymerization to hemozoin. In order to investigate the interactions of the marine compounds with their heme targets, a series of modern computational procedures were formulated, validated and then applied to theoretical systems. The validations of these algorithms, before their application to the marine compound-heme systems, were achieved through two case studies. The first was used to investigate the applicability of the statistical docking algorithm AutoDock to be used for the exploration of conformational space around the heme target. A theoretical P. falciparum 1-deoxy-D-xylulose-5-phosphate reductoisomerase (PfDXR) enzyme model, constructed by the Biochemistry Department at Rhodes University, provided the ideal model to validate the AutoDock program. The protein model was accordingly subjected to rigorous docking simulations with over 30 different ligand molecules using the AutoDock algorithm which allowed for the docking algorithm’s limitations to be ascertained and improved upon. This investigation facilitated the successful validation of the protein model, which can now be used for the rational design of new PfDXR-inhibiting anti-plasmodial compounds, as well as enabling us to propose an improvement of the docking algorithm for application to the heme systems. The second case study was used to investigate the applicability of an ab initio molecular dynamics algorithm for simulation of bond breaking/forming events between the marine compounds and their heme target. This validation involved the exploration of intermolecular interactions in a naturally occurring nonoligomeric zipper using the Car-Parrinello Molecular Dynamics (CPMD) method. This study allowed us to propose a model for the intermolecular forces responsible for zipper self-assembly and showcased the CPMD method’s abilities to simulate and predict bond forming/breaking events. Data from the computational analyses suggested that the interactions between marine isonitriles, isocyanates and isothiocyanates occur through bond-less electrostatic attractions rather than through formal intermolecular bonds as had been previously suggested. Accordingly, a simple bicyclic tertiary isonitrile (5.14) was synthesized using Kitano et al’s relatively underutilized isonitrile synthetic method for the conversion of tertiary alcohols to their corresponding isonitriles. This compound’s potential for heme detoxification inhibition was then explored in vitro via the pyridine-hemochrome assay. The assay data suggested that the synthesized isonitrile was capable of inhibiting heme polymerization in a similar fashion to the known inhibitor chloroquine. Attempts to synthesize tricyclic analogues of 5.14 were unsuccessful and highlighted the limitation of Kitano et al’s isonitrile synthetic methodology.
- Full Text:
- Date Issued: 2011
- Authors: Adendorff, Matthew Ralph
- Date: 2011 , 2010-05-17
- Subjects: Isocyanides , Isocyanates , Marine pharmacology , Antimalarials , Antimalarials -- Development , Drug development
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4398 , http://hdl.handle.net/10962/d1006674 , Isocyanides , Isocyanates , Marine pharmacology , Antimalarials , Antimalarials -- Development , Drug development
- Description: The development of Plasmodium falciparum malarial resistance to the current armoury of anti-malarial drugs requires the development of new treatments to help combat this disease. The marine environment is a well established source of potential pharmaceuticals. Of interest to us are isonitrile, isocyanate and isothiocyanate compounds isolated from marine sponges and molluscs which have exhibited nano-molar anti-plasmodial activities. Through quantitative structure-activity relation studies (QSAR), a literature precedent exists for a pseudoreceptor model from which a pharmacophore for the design of novel anti-malarial agents was proposed. The current theory suggests that these marine compounds exert their inhibitory action through interfering with the heme detoxification pathway in P. falciparum. We propose that the computational methods used to draw detailed conclusions about the mode of action of these marine compounds were inadequate. This thesis addresses this problem using contemporary computational methodologies and seeks to propose a more robust method for the rational design of new anti-malarial drug compounds that inhibit heme polymerization to hemozoin. In order to investigate the interactions of the marine compounds with their heme targets, a series of modern computational procedures were formulated, validated and then applied to theoretical systems. The validations of these algorithms, before their application to the marine compound-heme systems, were achieved through two case studies. The first was used to investigate the applicability of the statistical docking algorithm AutoDock to be used for the exploration of conformational space around the heme target. A theoretical P. falciparum 1-deoxy-D-xylulose-5-phosphate reductoisomerase (PfDXR) enzyme model, constructed by the Biochemistry Department at Rhodes University, provided the ideal model to validate the AutoDock program. The protein model was accordingly subjected to rigorous docking simulations with over 30 different ligand molecules using the AutoDock algorithm which allowed for the docking algorithm’s limitations to be ascertained and improved upon. This investigation facilitated the successful validation of the protein model, which can now be used for the rational design of new PfDXR-inhibiting anti-plasmodial compounds, as well as enabling us to propose an improvement of the docking algorithm for application to the heme systems. The second case study was used to investigate the applicability of an ab initio molecular dynamics algorithm for simulation of bond breaking/forming events between the marine compounds and their heme target. This validation involved the exploration of intermolecular interactions in a naturally occurring nonoligomeric zipper using the Car-Parrinello Molecular Dynamics (CPMD) method. This study allowed us to propose a model for the intermolecular forces responsible for zipper self-assembly and showcased the CPMD method’s abilities to simulate and predict bond forming/breaking events. Data from the computational analyses suggested that the interactions between marine isonitriles, isocyanates and isothiocyanates occur through bond-less electrostatic attractions rather than through formal intermolecular bonds as had been previously suggested. Accordingly, a simple bicyclic tertiary isonitrile (5.14) was synthesized using Kitano et al’s relatively underutilized isonitrile synthetic method for the conversion of tertiary alcohols to their corresponding isonitriles. This compound’s potential for heme detoxification inhibition was then explored in vitro via the pyridine-hemochrome assay. The assay data suggested that the synthesized isonitrile was capable of inhibiting heme polymerization in a similar fashion to the known inhibitor chloroquine. Attempts to synthesize tricyclic analogues of 5.14 were unsuccessful and highlighted the limitation of Kitano et al’s isonitrile synthetic methodology.
- Full Text:
- Date Issued: 2011
The influence of selected non-governmental organisations (NGOs) on policy-making in the Eastern Cape Amathole District Municipality and the eight local municipalities within the district
- Authors: Aiyegoro, Adeola Ikeoluwa
- Date: 2011
- Subjects: Non-governmental organizations -- South Africa -- Eastern Cape , Municipal government -- South Africa -- Eastern Cape , Local government -- South Africa -- Eastern Cape , Municipal officials and employees -- South Africa -- Eastern Cape , Policy sciences
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: vital:11644 , http://hdl.handle.net/10353/d1001253 , Non-governmental organizations -- South Africa -- Eastern Cape , Municipal government -- South Africa -- Eastern Cape , Local government -- South Africa -- Eastern Cape , Municipal officials and employees -- South Africa -- Eastern Cape , Policy sciences
- Description: Since 1994, the South African Government embarked on an ambitious Reconstruction and Development Program (RDP) to correct the injustices of the past. One of the major programmes, which the government is implementing within the RDP framework, is the ―Integrated National Electrification Programme‖ (INEP) with the aim to address the electricity backlog by 2012. Recent figures from Statistics SA, indicate substantial progress with regard to access to electricity throughout the country and especially in previously disadvantaged areas. This study is an investigation of the impact of access to free basic electricity (FBE) on the welfare of indigent households in Buffalo City Municipality (BCM). This study aims at better understanding ways in which indigent households use electricity and to what extent access to electricity is improving the level of poverty in the households. Empirical evidences from pro-poor electrification programmes worldwide and especially in Asia suggest that greater access to electricity by poor people leads to economic and social development at both micro and macro levels. This study investigates the impact of electricity on household poverty, with focus on household income, household health and children‘s education. This study used mixed research methods to investigate the research problem. Both quantitative and qualitative data were collected using survey questionnaires, focus group discussions and interviews of key informants.
- Full Text:
- Date Issued: 2011
- Authors: Aiyegoro, Adeola Ikeoluwa
- Date: 2011
- Subjects: Non-governmental organizations -- South Africa -- Eastern Cape , Municipal government -- South Africa -- Eastern Cape , Local government -- South Africa -- Eastern Cape , Municipal officials and employees -- South Africa -- Eastern Cape , Policy sciences
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: vital:11644 , http://hdl.handle.net/10353/d1001253 , Non-governmental organizations -- South Africa -- Eastern Cape , Municipal government -- South Africa -- Eastern Cape , Local government -- South Africa -- Eastern Cape , Municipal officials and employees -- South Africa -- Eastern Cape , Policy sciences
- Description: Since 1994, the South African Government embarked on an ambitious Reconstruction and Development Program (RDP) to correct the injustices of the past. One of the major programmes, which the government is implementing within the RDP framework, is the ―Integrated National Electrification Programme‖ (INEP) with the aim to address the electricity backlog by 2012. Recent figures from Statistics SA, indicate substantial progress with regard to access to electricity throughout the country and especially in previously disadvantaged areas. This study is an investigation of the impact of access to free basic electricity (FBE) on the welfare of indigent households in Buffalo City Municipality (BCM). This study aims at better understanding ways in which indigent households use electricity and to what extent access to electricity is improving the level of poverty in the households. Empirical evidences from pro-poor electrification programmes worldwide and especially in Asia suggest that greater access to electricity by poor people leads to economic and social development at both micro and macro levels. This study investigates the impact of electricity on household poverty, with focus on household income, household health and children‘s education. This study used mixed research methods to investigate the research problem. Both quantitative and qualitative data were collected using survey questionnaires, focus group discussions and interviews of key informants.
- Full Text:
- Date Issued: 2011
An analysis of the long run comovements between financial system development and mining production in South Africa
- Authors: Ajagbe, Stephen Mayowa
- Date: 2011
- Subjects: Economic development -- South Africa , Econometric models , Mineral industries -- Economic aspects -- South Africa , South Africa -- Economic conditions , South Africa -- Economic policy , Principal components analysis , Cointegration , Stock exchanges -- South Africa , Banks and banking -- South Africa , Foreign exchange rates
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:955 , http://hdl.handle.net/10962/d1002689 , Economic development -- South Africa , Econometric models , Mineral industries -- Economic aspects -- South Africa , South Africa -- Economic conditions , South Africa -- Economic policy , Principal components analysis , Cointegration , Stock exchanges -- South Africa , Banks and banking -- South Africa , Foreign exchange rates
- Description: This study examines the nature of the relationship which exists between mining sector production and development of the financial systems in South Africa. This is particularly important in that the mining sector is considered to be one of the major contributors to the country’s overall economic growth. South Africa is also considered to have a very well developed financial system, to the point where the dominance of one over the other is difficult to identify. Therefore offering insight into the nature of this relationship will assist policy makers in identifying the most effective policies in order to ensure that the developments within the financial systems impact appropriately on the mining sector, and ultimately on the economy. In addition to using the conventional proxies of financial system development, this study utilises the principal component analysis (PCA) to construct an index for the entire financial system. The multivariate cointegration approach as proposed by Johansen (1988) and Johansen and Juselius (1990) was then used to estimate the relationship between the development of the financial systems and the mining sector production for the period 1988-2008. The study reveals mixed results for different measures of financial system development. Those involving the banking system show that a negative relationship exists between total mining production and total credit extended to the private sector, while liquid liabilities has a positive relationship. Similarly, with the stock market system, mixed results are also obtained which reveal a negative relationship between total mining production and stock market capitalisation, while a positive relationship is found with secondary market turnover. Of all the financial system variables, only that of stock market capitalisation was found to be significant. The result with the financial development index reveals that a significant negative relationship exists between financial system development and total mining sector production. Results on the other variables controlled in the estimation show that positive and significant relationships exist between total mining production and both nominal exchange rate and political stability respectively. Increased mining production therefore takes place in periods of appreciating exchange rates, and similarly in the post-apartheid era. On the other hand, negative relationships were found for both trade openness and inflation control variables. The impulse response and variance decomposition analyses showed that total mining production explains the largest amount of shocks within itself. Overall, the study reveals that the mining sector might not have benefited much from the development in the South African financial system.
- Full Text:
- Date Issued: 2011
- Authors: Ajagbe, Stephen Mayowa
- Date: 2011
- Subjects: Economic development -- South Africa , Econometric models , Mineral industries -- Economic aspects -- South Africa , South Africa -- Economic conditions , South Africa -- Economic policy , Principal components analysis , Cointegration , Stock exchanges -- South Africa , Banks and banking -- South Africa , Foreign exchange rates
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:955 , http://hdl.handle.net/10962/d1002689 , Economic development -- South Africa , Econometric models , Mineral industries -- Economic aspects -- South Africa , South Africa -- Economic conditions , South Africa -- Economic policy , Principal components analysis , Cointegration , Stock exchanges -- South Africa , Banks and banking -- South Africa , Foreign exchange rates
- Description: This study examines the nature of the relationship which exists between mining sector production and development of the financial systems in South Africa. This is particularly important in that the mining sector is considered to be one of the major contributors to the country’s overall economic growth. South Africa is also considered to have a very well developed financial system, to the point where the dominance of one over the other is difficult to identify. Therefore offering insight into the nature of this relationship will assist policy makers in identifying the most effective policies in order to ensure that the developments within the financial systems impact appropriately on the mining sector, and ultimately on the economy. In addition to using the conventional proxies of financial system development, this study utilises the principal component analysis (PCA) to construct an index for the entire financial system. The multivariate cointegration approach as proposed by Johansen (1988) and Johansen and Juselius (1990) was then used to estimate the relationship between the development of the financial systems and the mining sector production for the period 1988-2008. The study reveals mixed results for different measures of financial system development. Those involving the banking system show that a negative relationship exists between total mining production and total credit extended to the private sector, while liquid liabilities has a positive relationship. Similarly, with the stock market system, mixed results are also obtained which reveal a negative relationship between total mining production and stock market capitalisation, while a positive relationship is found with secondary market turnover. Of all the financial system variables, only that of stock market capitalisation was found to be significant. The result with the financial development index reveals that a significant negative relationship exists between financial system development and total mining sector production. Results on the other variables controlled in the estimation show that positive and significant relationships exist between total mining production and both nominal exchange rate and political stability respectively. Increased mining production therefore takes place in periods of appreciating exchange rates, and similarly in the post-apartheid era. On the other hand, negative relationships were found for both trade openness and inflation control variables. The impulse response and variance decomposition analyses showed that total mining production explains the largest amount of shocks within itself. Overall, the study reveals that the mining sector might not have benefited much from the development in the South African financial system.
- Full Text:
- Date Issued: 2011
Formation, surface characterization, and electrocatalytic application of self-assembled monolayer films of tetra-substituted manganese, iron, and cobalt benzylthio phthalocyanine complexes
- Akinbulu, Isaac Adebayo, Ozoemena, Kenneth Iyke, Nyokong, Tebello
- Authors: Akinbulu, Isaac Adebayo , Ozoemena, Kenneth Iyke , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247163 , vital:51552 , xlink:href="https://doi.org/10.1007/s10008-010-1243-1"
- Description: Molecular thin films of manganese (SAM-2), iron (SAM-3), and cobalt (SAM-4) phthalocyanine complexes, non-peripherally tetra-substituted with benzylmercapto, were formed on polycrystalline gold disc electrode by self-assembly technique. Surface characteristics of the films were interrogated by cyclic voltammetry. Significant passivation of voltammetry processes associated with bare gold surface (gold oxidation and underpotential deposition of copper) confirmed formation of the films. Electrocatalytic property of the films was evidenced from better voltammetry responses (less positive oxidation potential and better current signal) of the insecticide, carbofuran, on these films, relative to that on bare gold electrode. In terms of less positive oxidation potential, the FePc derivative (3) gave the best response, while the best current signal was observed on SAM-2-modified gold electrode. The average heterogeneous rate constant, k, for the oxidation of carbofuran was 3.6 × 10−2 cm s−1 on the SAM film with the best current signal (SAM-2).
- Full Text:
- Date Issued: 2011
- Authors: Akinbulu, Isaac Adebayo , Ozoemena, Kenneth Iyke , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247163 , vital:51552 , xlink:href="https://doi.org/10.1007/s10008-010-1243-1"
- Description: Molecular thin films of manganese (SAM-2), iron (SAM-3), and cobalt (SAM-4) phthalocyanine complexes, non-peripherally tetra-substituted with benzylmercapto, were formed on polycrystalline gold disc electrode by self-assembly technique. Surface characteristics of the films were interrogated by cyclic voltammetry. Significant passivation of voltammetry processes associated with bare gold surface (gold oxidation and underpotential deposition of copper) confirmed formation of the films. Electrocatalytic property of the films was evidenced from better voltammetry responses (less positive oxidation potential and better current signal) of the insecticide, carbofuran, on these films, relative to that on bare gold electrode. In terms of less positive oxidation potential, the FePc derivative (3) gave the best response, while the best current signal was observed on SAM-2-modified gold electrode. The average heterogeneous rate constant, k, for the oxidation of carbofuran was 3.6 × 10−2 cm s−1 on the SAM film with the best current signal (SAM-2).
- Full Text:
- Date Issued: 2011
Surface properties and electrocatalytic applications of metallophthalocyanines confined on electrode surfaces
- Authors: Akinbulu, Isaac Adebayo
- Date: 2011
- Subjects: Phthalocyanines Electrochemistry Electrocatalysis Pesticides
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4365 , http://hdl.handle.net/10962/d1005030
- Description: New cobalt (13, 16 19 and 22), manganese (14, 17, 20 and 23) and iron (15, 18, 21 and 24)phthalocyanine complexes were synthesized and characterized. The UV-Vis spectral properties of the complexes were typical of the nature of central metal and position of substituent on the Pc ligand. Their electrochemical behaviors were signatures of the central metals, with varying influences of the nature and position of substituents. Nanocomposite of complex 18 and single walled carbon nanotubes (SWCNTs) (SWCNT-18)was fabricated. Formation of this nano-composite was confirmed by infrared (IR)spectroscopy, X-ray diffraction (XRD) spectroscopy and transmission electron microscopy (TEM). Self-assembled monolayers (SAMs) of SWCNT-18, complexes 13-15, and 20 were electropolymerized on glassy carbon electrodes (GCE). Complex 14 was also electrodeposited on GCE. Surface properties of the SAMs were consistent with the molecular feature of the substituent and the nature of central metal in the adsorbed species, while those of the MnPc modified GCEs were dependent on point of substitution and number of substituent. The SAM-modified gold electrodes were used for the electrocatalytic oxidation of the carbamate insecticide, carbofuran. Amplification of the current signal of the insecticide, at more energetically feasible oxidation potentials, on the SAM-modified gold electrodes, relative to bare gold electrode,justified electrocatalysis. There was enhanced sensitivity (attributed to the presence of SWCNT) of the SWCNT-18-SAM-modified gold electrode towards carbofuran, relative to the signals observed on the other SAMs. Current response of the insecticide,bendiocarb, was also intensified, at more favorable oxidation potentials, on the MnPc (14 and 17) modified GCEs, relative to the response on bare GCE, substantiating electrocatalysis. Also, catalysis of the oxidation of the herbicide, bentazon, was observed on polymeric film of complex 20. The current response of the herbicide on this film was better than that observed on bare GCE. Electrocatalysis of the analytes, on the respective modified electrodes, occurred via closely related mechanisms.
- Full Text:
- Date Issued: 2011
- Authors: Akinbulu, Isaac Adebayo
- Date: 2011
- Subjects: Phthalocyanines Electrochemistry Electrocatalysis Pesticides
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4365 , http://hdl.handle.net/10962/d1005030
- Description: New cobalt (13, 16 19 and 22), manganese (14, 17, 20 and 23) and iron (15, 18, 21 and 24)phthalocyanine complexes were synthesized and characterized. The UV-Vis spectral properties of the complexes were typical of the nature of central metal and position of substituent on the Pc ligand. Their electrochemical behaviors were signatures of the central metals, with varying influences of the nature and position of substituents. Nanocomposite of complex 18 and single walled carbon nanotubes (SWCNTs) (SWCNT-18)was fabricated. Formation of this nano-composite was confirmed by infrared (IR)spectroscopy, X-ray diffraction (XRD) spectroscopy and transmission electron microscopy (TEM). Self-assembled monolayers (SAMs) of SWCNT-18, complexes 13-15, and 20 were electropolymerized on glassy carbon electrodes (GCE). Complex 14 was also electrodeposited on GCE. Surface properties of the SAMs were consistent with the molecular feature of the substituent and the nature of central metal in the adsorbed species, while those of the MnPc modified GCEs were dependent on point of substitution and number of substituent. The SAM-modified gold electrodes were used for the electrocatalytic oxidation of the carbamate insecticide, carbofuran. Amplification of the current signal of the insecticide, at more energetically feasible oxidation potentials, on the SAM-modified gold electrodes, relative to bare gold electrode,justified electrocatalysis. There was enhanced sensitivity (attributed to the presence of SWCNT) of the SWCNT-18-SAM-modified gold electrode towards carbofuran, relative to the signals observed on the other SAMs. Current response of the insecticide,bendiocarb, was also intensified, at more favorable oxidation potentials, on the MnPc (14 and 17) modified GCEs, relative to the response on bare GCE, substantiating electrocatalysis. Also, catalysis of the oxidation of the herbicide, bentazon, was observed on polymeric film of complex 20. The current response of the herbicide on this film was better than that observed on bare GCE. Electrocatalysis of the analytes, on the respective modified electrodes, occurred via closely related mechanisms.
- Full Text:
- Date Issued: 2011
Assessment of the antibacterial properties of n-Hexane extract of Cocos Nucifera and its interactions with some conventional antibiotics
- Authors: Akinyele, Taiwo Adesola
- Date: 2011
- Subjects: Coconut palm , Microbial sensitivity tests , Gram-negative bacterial infections , Vibrio infections , Antibiotics , Hexane , Extracts
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11245 , http://hdl.handle.net/10353/416 , Coconut palm , Microbial sensitivity tests , Gram-negative bacterial infections , Vibrio infections , Antibiotics , Hexane , Extracts
- Description: Cocos nucifera belong to the family Aracaceae (palm Family). The English name is coconut and it is used extensively as medicinal remedies against infections such as urinary tract infections, gastro intestinal infections, skin and wound infections. The in vitro antibacterial (including anti-listerial and anti-vibrio) properties as well as the evaluation of the combination potentials of the plant extract with six front-line antibiotics were evaluated in this study using standard procedures. The in vitro anti-listerial properties of the crude aqueous and n-Hexane extract of the husk of Cocos nucifera were carried out against 37 Listeria isolates. Twenty-nine of the test organisms were susceptible to the aqueous extract while thirty were susceptible to the n-Hexane extract both at the screening concentration of 25 mg/ml. Minimum Inhibitory Concentration (MIC) values for all the susceptible bacteria ranged between 0.6 - 5.0 mg/ml. For the aqueous extract, average log reduction in viable cell count ranged between 0.32 Log10 and 4.8 Log10 CFU/ml after 8 hours interaction in 1 × MIC and 2 × MIC. For the n-Hexane extract, the log reduction ranged between 2.4 Log10 and 6.2 Log10 CFU/ml after 8 hours interaction in 1 × MIC and 2 × MIC. The time-kill characteristics of the two extracts suggest that at higher concentration (2 × MIC) and longer duration of interaction (8 hr), more bacteria were killed. In vitro anti-vibrio and antibacterial properties experiment revealed that of all the 45 vibrio and 25 bacteria strains that was tested, 37 were susceptible to the aqueous extract and 38 to the n-Hexane extract, while 17 were susceptible to the aqueous extract and 21 to the n-Hexane extract. Minimum Inhibitory Concentration (MIC) values for all the susceptible bacteria ranged between 0.3 - 5.0 mg/ml. viii The time kill studies revealed that for the aqueous extract, average log reduction in viable cell count in time kill assay ranged between 0.12 Log10 and 4.2 Log10 CFU/ml after 8 hr interaction at 1 × MIC and 2 × MIC. For the n-Hexane extract, the log reduction ranged between 0.56 Log10 and 6.4 Log10 CFU/ml after 8 hr interaction in 1 × MIC and 2 × MIC. In the test for the combination interactions, the checkerboard method revealed synergy of 67% and indifferent of 33%, while the time kill assay detected synergy in 72% and indifferent in 28% of the combinations tested. The synergy detected was not specific to any of the antibiotics or the Gram reaction of the bacteria, and no antagonism was detected. We conclude that the aqueous and n-Hexane extract of the husk of C. nucifera contains potential broad spectrum antibiotics resistance modulating compounds that could be relevant in the treatment of infections caused by these pathogens. In addition, the husk which is being discarded as agro waste will opens up a vista of opportunities for utilization for therapeutic purposes
- Full Text:
- Date Issued: 2011
- Authors: Akinyele, Taiwo Adesola
- Date: 2011
- Subjects: Coconut palm , Microbial sensitivity tests , Gram-negative bacterial infections , Vibrio infections , Antibiotics , Hexane , Extracts
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11245 , http://hdl.handle.net/10353/416 , Coconut palm , Microbial sensitivity tests , Gram-negative bacterial infections , Vibrio infections , Antibiotics , Hexane , Extracts
- Description: Cocos nucifera belong to the family Aracaceae (palm Family). The English name is coconut and it is used extensively as medicinal remedies against infections such as urinary tract infections, gastro intestinal infections, skin and wound infections. The in vitro antibacterial (including anti-listerial and anti-vibrio) properties as well as the evaluation of the combination potentials of the plant extract with six front-line antibiotics were evaluated in this study using standard procedures. The in vitro anti-listerial properties of the crude aqueous and n-Hexane extract of the husk of Cocos nucifera were carried out against 37 Listeria isolates. Twenty-nine of the test organisms were susceptible to the aqueous extract while thirty were susceptible to the n-Hexane extract both at the screening concentration of 25 mg/ml. Minimum Inhibitory Concentration (MIC) values for all the susceptible bacteria ranged between 0.6 - 5.0 mg/ml. For the aqueous extract, average log reduction in viable cell count ranged between 0.32 Log10 and 4.8 Log10 CFU/ml after 8 hours interaction in 1 × MIC and 2 × MIC. For the n-Hexane extract, the log reduction ranged between 2.4 Log10 and 6.2 Log10 CFU/ml after 8 hours interaction in 1 × MIC and 2 × MIC. The time-kill characteristics of the two extracts suggest that at higher concentration (2 × MIC) and longer duration of interaction (8 hr), more bacteria were killed. In vitro anti-vibrio and antibacterial properties experiment revealed that of all the 45 vibrio and 25 bacteria strains that was tested, 37 were susceptible to the aqueous extract and 38 to the n-Hexane extract, while 17 were susceptible to the aqueous extract and 21 to the n-Hexane extract. Minimum Inhibitory Concentration (MIC) values for all the susceptible bacteria ranged between 0.3 - 5.0 mg/ml. viii The time kill studies revealed that for the aqueous extract, average log reduction in viable cell count in time kill assay ranged between 0.12 Log10 and 4.2 Log10 CFU/ml after 8 hr interaction at 1 × MIC and 2 × MIC. For the n-Hexane extract, the log reduction ranged between 0.56 Log10 and 6.4 Log10 CFU/ml after 8 hr interaction in 1 × MIC and 2 × MIC. In the test for the combination interactions, the checkerboard method revealed synergy of 67% and indifferent of 33%, while the time kill assay detected synergy in 72% and indifferent in 28% of the combinations tested. The synergy detected was not specific to any of the antibiotics or the Gram reaction of the bacteria, and no antagonism was detected. We conclude that the aqueous and n-Hexane extract of the husk of C. nucifera contains potential broad spectrum antibiotics resistance modulating compounds that could be relevant in the treatment of infections caused by these pathogens. In addition, the husk which is being discarded as agro waste will opens up a vista of opportunities for utilization for therapeutic purposes
- Full Text:
- Date Issued: 2011
Widows' experiences of spousal mourning among AmaXhosa: an interpretative phenomenological study
- Authors: Akol, Grace
- Date: 2011
- Subjects: Widowhood -- South Africa -- Eastern Cape , Widows -- South Africa -- Eastern Cape , Xhosa (African people) -- Funeral customs and rites , Xhosa (African people) -- Psychology , Bereavement -- Psychological aspects , Mourning customs -- South Africa -- Eastern Cape , Death -- Social aspects -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Soc Sc (Psych)
- Identifier: vital:11609 , http://hdl.handle.net/10353/523 , Widowhood -- South Africa -- Eastern Cape , Widows -- South Africa -- Eastern Cape , Xhosa (African people) -- Funeral customs and rites , Xhosa (African people) -- Psychology , Bereavement -- Psychological aspects , Mourning customs -- South Africa -- Eastern Cape , Death -- Social aspects -- South Africa -- Eastern Cape
- Description: This study was conducted on the mourning rituals of the AmaXhosa widows of the Eastern Cape Province of South Africa. The study focused on the descriptive presentation of the experiences of the AmaXhosa widows in the Buffalo City municipality of the Province. The study sought to establish the widows’ perceptions regarding the mourning rituals and to interpret their experiences within the context of contemporary cultural, religious, gender and socio-political influences. The experiences among the widows interviewed were found to have a similar context but their perceptions about the mourning rituals were different between the widows younger than 40 years and those older than 50 years. Widows from urban and rural areas of East London, Mdantsane Township and from within a 60 kilometre radius of East London were interviewed. Purposive random sampling was used to identify an equal number of either urban or rural voluntary participants for the study. Structured interviews were held with widows ranging in age from 29 to 91 years. An interpretative phenomenological analysis of the recorded discussions was conducted. The experiences of the AmaXhosa widows during the conduct of the mourning rituals are described. The key findings of the study indicated that most of the widows felt they had to go through the mourning rituals mainly to show respect for their departed husbands and so that the dignity of the family and clan was maintained. The mourning rituals seemed mostly to have negative implications for the widows such as a lack of family and financial support and being treated as social outcasts; however the rituals also seemed to help the women adjust to their new status as widows. Although the mourning rituals were embedded in the socio-cultural tradition generally followed by the AmaXhosa, religious beliefs also influenced some of the traditions by introducing changes in the way some widows conducted the mourning rituals. For example, some religions advocated for shorter periods of mourning than usual as well as wearing different types of mourning clothes from the usual black or purple dress. Overall the perceptions of the older widows aged above 50 years revealed that they had no reservations about performing the mourning rituals and quite readily and unquestioningly accepted the customs. The younger widows aged below 40 years on the other hand felt that the mourning rituals were biased against women and did not serve a useful purpose and even proposed changes to the manner in which the mourning rituals are conducted particularly the shortening of the mourning period from 12 to 6 months or less. However, they seemed to recognize the role played by the mourning ritual in lessening and possibly healing the pain and sorrow caused by their bereavement.
- Full Text:
- Date Issued: 2011
- Authors: Akol, Grace
- Date: 2011
- Subjects: Widowhood -- South Africa -- Eastern Cape , Widows -- South Africa -- Eastern Cape , Xhosa (African people) -- Funeral customs and rites , Xhosa (African people) -- Psychology , Bereavement -- Psychological aspects , Mourning customs -- South Africa -- Eastern Cape , Death -- Social aspects -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Soc Sc (Psych)
- Identifier: vital:11609 , http://hdl.handle.net/10353/523 , Widowhood -- South Africa -- Eastern Cape , Widows -- South Africa -- Eastern Cape , Xhosa (African people) -- Funeral customs and rites , Xhosa (African people) -- Psychology , Bereavement -- Psychological aspects , Mourning customs -- South Africa -- Eastern Cape , Death -- Social aspects -- South Africa -- Eastern Cape
- Description: This study was conducted on the mourning rituals of the AmaXhosa widows of the Eastern Cape Province of South Africa. The study focused on the descriptive presentation of the experiences of the AmaXhosa widows in the Buffalo City municipality of the Province. The study sought to establish the widows’ perceptions regarding the mourning rituals and to interpret their experiences within the context of contemporary cultural, religious, gender and socio-political influences. The experiences among the widows interviewed were found to have a similar context but their perceptions about the mourning rituals were different between the widows younger than 40 years and those older than 50 years. Widows from urban and rural areas of East London, Mdantsane Township and from within a 60 kilometre radius of East London were interviewed. Purposive random sampling was used to identify an equal number of either urban or rural voluntary participants for the study. Structured interviews were held with widows ranging in age from 29 to 91 years. An interpretative phenomenological analysis of the recorded discussions was conducted. The experiences of the AmaXhosa widows during the conduct of the mourning rituals are described. The key findings of the study indicated that most of the widows felt they had to go through the mourning rituals mainly to show respect for their departed husbands and so that the dignity of the family and clan was maintained. The mourning rituals seemed mostly to have negative implications for the widows such as a lack of family and financial support and being treated as social outcasts; however the rituals also seemed to help the women adjust to their new status as widows. Although the mourning rituals were embedded in the socio-cultural tradition generally followed by the AmaXhosa, religious beliefs also influenced some of the traditions by introducing changes in the way some widows conducted the mourning rituals. For example, some religions advocated for shorter periods of mourning than usual as well as wearing different types of mourning clothes from the usual black or purple dress. Overall the perceptions of the older widows aged above 50 years revealed that they had no reservations about performing the mourning rituals and quite readily and unquestioningly accepted the customs. The younger widows aged below 40 years on the other hand felt that the mourning rituals were biased against women and did not serve a useful purpose and even proposed changes to the manner in which the mourning rituals are conducted particularly the shortening of the mourning period from 12 to 6 months or less. However, they seemed to recognize the role played by the mourning ritual in lessening and possibly healing the pain and sorrow caused by their bereavement.
- Full Text:
- Date Issued: 2011
The challenges facing non-governmental organisations in transforming conflict through capacity-building in Nothern Uganda
- Authors: Akurut, Catherine
- Date: 2011
- Subjects: Conflict management -- Uganda , Peace-building -- Uganda
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: vital:8189 , http://hdl.handle.net/10948/1412 , Conflict management -- Uganda , Peace-building -- Uganda
- Description: Capacity-building is an essential component of post-conflict reconstruction (PCR) and peace-building in the aftermath of violent conflict. Civilians, mainly women and children are driven or abducted from their homes during violent conflict and suffer various abuses and atrocities. Many spend the duration of the conflict as refugees in Internally Displaced People (IDP) camps in neighbouring countries. Violent conflict impinges on their psychological well-being and socio-economic development making their re-integration into their former communities extremely complex and challenging. In the case of Northern Uganda, the conflict lasted for over two decades. However, since the ―Cessation of Hostilities Agreement‖ of 2006, the peace-building process has been particularly evident here. Numerous stakeholders have been involved in the capacity-building processes in Northern Uganda, and one such organisation is the Friends of Orphans (FRO) in Pader district, Northern Uganda. The purpose of this research study is to explore the challenges facing the FRO in transforming conflict and building sustainable peace through capacity-building in Pader district. The study explores the programmes the organisation implements and investigates how these programmes are relevant for the transformation of conflict. Apart from reviewing the literature, the researcher conducted semi-structured interviews and used participant observation. The employees of the FRO – all of whom are involved with capacity-building in these communities – participated in these interviews in their capacities as social workers, teachers, administrators and field workers. The beneficiaries of these programmes include former child soldiers, abductees, child mothers, land mine survivors and orphans. Lessons learned by the FRO, as well as the researcher‘s recommendations, are discussed in the study in order to assist the future work of the organisation and other stakeholders who have devoted their efforts to the recovery of areas emerging from conflict.
- Full Text:
- Date Issued: 2011
- Authors: Akurut, Catherine
- Date: 2011
- Subjects: Conflict management -- Uganda , Peace-building -- Uganda
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: vital:8189 , http://hdl.handle.net/10948/1412 , Conflict management -- Uganda , Peace-building -- Uganda
- Description: Capacity-building is an essential component of post-conflict reconstruction (PCR) and peace-building in the aftermath of violent conflict. Civilians, mainly women and children are driven or abducted from their homes during violent conflict and suffer various abuses and atrocities. Many spend the duration of the conflict as refugees in Internally Displaced People (IDP) camps in neighbouring countries. Violent conflict impinges on their psychological well-being and socio-economic development making their re-integration into their former communities extremely complex and challenging. In the case of Northern Uganda, the conflict lasted for over two decades. However, since the ―Cessation of Hostilities Agreement‖ of 2006, the peace-building process has been particularly evident here. Numerous stakeholders have been involved in the capacity-building processes in Northern Uganda, and one such organisation is the Friends of Orphans (FRO) in Pader district, Northern Uganda. The purpose of this research study is to explore the challenges facing the FRO in transforming conflict and building sustainable peace through capacity-building in Pader district. The study explores the programmes the organisation implements and investigates how these programmes are relevant for the transformation of conflict. Apart from reviewing the literature, the researcher conducted semi-structured interviews and used participant observation. The employees of the FRO – all of whom are involved with capacity-building in these communities – participated in these interviews in their capacities as social workers, teachers, administrators and field workers. The beneficiaries of these programmes include former child soldiers, abductees, child mothers, land mine survivors and orphans. Lessons learned by the FRO, as well as the researcher‘s recommendations, are discussed in the study in order to assist the future work of the organisation and other stakeholders who have devoted their efforts to the recovery of areas emerging from conflict.
- Full Text:
- Date Issued: 2011
Stories from forest, river and mountain : exploring children's cultural environmental narratives and their role in the transmission of cultural connection to and protection of biodiversity
- Authors: Alexander, Jamie Kim
- Date: 2011
- Subjects: Children and the environment -- South Africa -- Eastern Cape , Conservation of natural resources -- South Africa -- Eastern Cape -- Citizen participation , Environmental education -- South Africa -- Eastern Cape , Human ecology -- South Africa -- Eastern Cape , Oral tradition -- South Africa -- Eastern Cape , Social learning -- South Africa -- Eastern Cape , Traditional ecological knowledge -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:6061 , http://hdl.handle.net/10962/d1015267
- Description: Preservationist conservation created a legacy of national parks and protected areas that were surrounded by local people dispossessed of their land and denied the rights to use the resources they had previously relied upon. Although conservation is now shifting towards a more participatory approach, research gaps still exist in determining the meaning of 'the environment' and the role of local means of conservation in rural communities in South Africa. This study focused on children's cultural environmental narratives from two rural villages in the Eastern Cape, South Africa. Children from grades 4, 7 and 10 were involved in the study, and adult family members, local experts and village elders were included in the study to allow for comparison between children's and adult's narratives and to realise what Local Ecological Knowledge (LEK) was being passed on. This thesis considers children's use of the environment for play and their sense of place as key methods in ascertaining children's environmental narratives and perceptions. At both field sites, local experts and community elders possessed a wealth of cultural environmental narratives, but these narratives were not necessarily being passed on. Changing household structures and other socio-economic factors influence cultural environmental practices, which in turn have an impact on the cultural environmental narratives being passed down. In many cases, parents' safety fears strongly impacted upon children's access to the environment, resulting in gendered environmental knowledge. The study compared differing vegetation types and degrees of environmental access. The differing environments produced similar cultural environmental narratives, leading to new understandings in community environment relationships. Children living near the state administered forest had significantly less environmental knowledge, bringing about questions of sustainable bio-cultural diversity in the future. The recognition of cultural environmental values is especially important in the rural areas of South Africa, where unemployment and increased poverty levels have led to greater dependence on natural resources for social, economic and cultural purposes. It is proposed that local cultural environmental narratives and landscape perceptions be included into community conservation and environmental education policies and programmes to provide local solutions to the problem of biodiversity conservation in local contexts.
- Full Text:
- Date Issued: 2011
- Authors: Alexander, Jamie Kim
- Date: 2011
- Subjects: Children and the environment -- South Africa -- Eastern Cape , Conservation of natural resources -- South Africa -- Eastern Cape -- Citizen participation , Environmental education -- South Africa -- Eastern Cape , Human ecology -- South Africa -- Eastern Cape , Oral tradition -- South Africa -- Eastern Cape , Social learning -- South Africa -- Eastern Cape , Traditional ecological knowledge -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:6061 , http://hdl.handle.net/10962/d1015267
- Description: Preservationist conservation created a legacy of national parks and protected areas that were surrounded by local people dispossessed of their land and denied the rights to use the resources they had previously relied upon. Although conservation is now shifting towards a more participatory approach, research gaps still exist in determining the meaning of 'the environment' and the role of local means of conservation in rural communities in South Africa. This study focused on children's cultural environmental narratives from two rural villages in the Eastern Cape, South Africa. Children from grades 4, 7 and 10 were involved in the study, and adult family members, local experts and village elders were included in the study to allow for comparison between children's and adult's narratives and to realise what Local Ecological Knowledge (LEK) was being passed on. This thesis considers children's use of the environment for play and their sense of place as key methods in ascertaining children's environmental narratives and perceptions. At both field sites, local experts and community elders possessed a wealth of cultural environmental narratives, but these narratives were not necessarily being passed on. Changing household structures and other socio-economic factors influence cultural environmental practices, which in turn have an impact on the cultural environmental narratives being passed down. In many cases, parents' safety fears strongly impacted upon children's access to the environment, resulting in gendered environmental knowledge. The study compared differing vegetation types and degrees of environmental access. The differing environments produced similar cultural environmental narratives, leading to new understandings in community environment relationships. Children living near the state administered forest had significantly less environmental knowledge, bringing about questions of sustainable bio-cultural diversity in the future. The recognition of cultural environmental values is especially important in the rural areas of South Africa, where unemployment and increased poverty levels have led to greater dependence on natural resources for social, economic and cultural purposes. It is proposed that local cultural environmental narratives and landscape perceptions be included into community conservation and environmental education policies and programmes to provide local solutions to the problem of biodiversity conservation in local contexts.
- Full Text:
- Date Issued: 2011
Trophodynamics of the benthic and hyperbenthic communities inhabiting the Sub-Antarctic Prince Edward Islands : stable isotope and fatty acid signatures
- Authors: Allan, Elizabeth Louise
- Date: 2011
- Subjects: Benthos -- Prince Edward Islands Benthos -- Feeding and feeds -- Prince Edward Islands Benthos -- Nutrition -- Prince Edward Islands Prince Edward Islands
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5806 , http://hdl.handle.net/10962/d1006350
- Description: The aim of this study was to investigate spatial changes in the trophic and energy pathways of the benthic community in the shallow shelf waters of the sub-Antarctic Prince Edward Islands (PEI). A combination of stable isotope and fatty acid analyses were used to provide a time-integrated view of the assimilated feeding history of selected components of the PEI benthic community. This study forms part of the larger project entitled “Variability in the Southern Ocean ecosystems” and is a contribution to the South African National Antarctic Programme (SANAP). During austral autumn 2009, benthic specimens were collected from 10 stations (from depths of 70 to 295 m) in different regions around the PEI: inter-island shelf (upstream, between and downstream of the islands) and nearshore. Historical data were combined with new data collected during 2009 to assess the long-term trends in the feeding ecology of the benthos in the region of the islands. The stable isotope and fatty acid signatures of the benthic suspension- and deposit-feeding organisms generated during this study suggested that these two communities incorporated both phytoplankton and kelp in their diets. Stable isotope, and to a lesser extent fatty acid signatures, indicated that kelp contributed more to the diets of those organisms in close proximity to the kelp beds (nearshore stations) than those from the inter-island region. Overall, however, pelagic phytoplankton was the dominant food source in the diets of all organisms, even for those living near the kelp beds. Notable exceptions were the sponges and bryozoans, in which kelp and phytoplankton contributed similar proportions to their diets, most likely resulting from a size restricted feeding mode. There were, therefore, no distinct spatial differences in the importance of the various food sources. However, fatty acid compositional data indicated increased food quality between and within the lee of the islands compared to upstream. The organisms collected upstream of the PEI had substantially lower quantities of total fatty acids (TFAs) than organisms of the same species collected from nearshore, open shelf or downstream stations. The increased food quality between and within the lee of the islands was likely a result of the “island mass effect”, which reflects increased phytoplankton concentrations at the PEI. The fatty acid profiles of hyperbenthic shrimp Nauticaris marionis, a key species in the PEI ecosystem, revealed no distinct ontogenetic or spatial patterns. This result is in contrast to the stable isotope analyses, which detected both spatial and ontogenetic differences in the diet of the shrimp. Nearshore shrimp were more ₁₃C-enriched than those from the inter-island region, suggesting increased kelp entering the food web within these regions. In addition, the shrimps demonstrated enrichment in δ₁₃C and δ₁₅N signatures with an increase in size, resulting in a relatively distinct separation of size classes, thus reflecting niche separation through their diets. The fatty acid profiles revealed that the shrimp all contained large proportions of polyunsaturated fatty acids (PUFAs) and essential fatty acids (EFAs), indicating that the quality of food consumed was similar among size class and region despite the niche separation and variation in carbon sources utilised. In addition, diatom and dinoflagellate fatty acids (20:5ω3 and 22:6ω3, respectively) occurred in the highest proportions in N. marionis, highlighting the importance of phytoplankton (indirectly) in their diet. These results represent strong evidence that phytoplankton is an importance food source in the PEI ecosystem. The temporal investigation of isotope signatures in the benthos at the PEI indicated that N. marionis demonstrated an overall depletion in δ₁₃C signatures over the period of 1984 to 2009 (nearshore: -2.55 ‰, inter-island: -2.32 ‰). Overall, the benthic community showed similar depletions in δ13C signatures (from -1.96 to -4.70 ‰), suggesting that shifts have occurred in the carbon signatures at the base of the food web. The depletion in δ₁₃C signatures of the benthos at the PEI most likely reflects increased contributions of smaller slow growing phytoplankton cells (more depleted signatures than large fast growing cells) in the diets of these organisms over time. These diet shifts, in turn, suggest a decrease in productivity has occurred at the islands, likely due to a decreased frequency and intensity of the “island mass effect”. Decreased phytoplankton productivity at the PEI likely results from the southward shift in the average position of the sub-Antarctic Front (SAF), most likely in response to climate change, which in turn promotes flow-through conditions rather than retention at the PEI.
- Full Text:
- Date Issued: 2011
- Authors: Allan, Elizabeth Louise
- Date: 2011
- Subjects: Benthos -- Prince Edward Islands Benthos -- Feeding and feeds -- Prince Edward Islands Benthos -- Nutrition -- Prince Edward Islands Prince Edward Islands
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5806 , http://hdl.handle.net/10962/d1006350
- Description: The aim of this study was to investigate spatial changes in the trophic and energy pathways of the benthic community in the shallow shelf waters of the sub-Antarctic Prince Edward Islands (PEI). A combination of stable isotope and fatty acid analyses were used to provide a time-integrated view of the assimilated feeding history of selected components of the PEI benthic community. This study forms part of the larger project entitled “Variability in the Southern Ocean ecosystems” and is a contribution to the South African National Antarctic Programme (SANAP). During austral autumn 2009, benthic specimens were collected from 10 stations (from depths of 70 to 295 m) in different regions around the PEI: inter-island shelf (upstream, between and downstream of the islands) and nearshore. Historical data were combined with new data collected during 2009 to assess the long-term trends in the feeding ecology of the benthos in the region of the islands. The stable isotope and fatty acid signatures of the benthic suspension- and deposit-feeding organisms generated during this study suggested that these two communities incorporated both phytoplankton and kelp in their diets. Stable isotope, and to a lesser extent fatty acid signatures, indicated that kelp contributed more to the diets of those organisms in close proximity to the kelp beds (nearshore stations) than those from the inter-island region. Overall, however, pelagic phytoplankton was the dominant food source in the diets of all organisms, even for those living near the kelp beds. Notable exceptions were the sponges and bryozoans, in which kelp and phytoplankton contributed similar proportions to their diets, most likely resulting from a size restricted feeding mode. There were, therefore, no distinct spatial differences in the importance of the various food sources. However, fatty acid compositional data indicated increased food quality between and within the lee of the islands compared to upstream. The organisms collected upstream of the PEI had substantially lower quantities of total fatty acids (TFAs) than organisms of the same species collected from nearshore, open shelf or downstream stations. The increased food quality between and within the lee of the islands was likely a result of the “island mass effect”, which reflects increased phytoplankton concentrations at the PEI. The fatty acid profiles of hyperbenthic shrimp Nauticaris marionis, a key species in the PEI ecosystem, revealed no distinct ontogenetic or spatial patterns. This result is in contrast to the stable isotope analyses, which detected both spatial and ontogenetic differences in the diet of the shrimp. Nearshore shrimp were more ₁₃C-enriched than those from the inter-island region, suggesting increased kelp entering the food web within these regions. In addition, the shrimps demonstrated enrichment in δ₁₃C and δ₁₅N signatures with an increase in size, resulting in a relatively distinct separation of size classes, thus reflecting niche separation through their diets. The fatty acid profiles revealed that the shrimp all contained large proportions of polyunsaturated fatty acids (PUFAs) and essential fatty acids (EFAs), indicating that the quality of food consumed was similar among size class and region despite the niche separation and variation in carbon sources utilised. In addition, diatom and dinoflagellate fatty acids (20:5ω3 and 22:6ω3, respectively) occurred in the highest proportions in N. marionis, highlighting the importance of phytoplankton (indirectly) in their diet. These results represent strong evidence that phytoplankton is an importance food source in the PEI ecosystem. The temporal investigation of isotope signatures in the benthos at the PEI indicated that N. marionis demonstrated an overall depletion in δ₁₃C signatures over the period of 1984 to 2009 (nearshore: -2.55 ‰, inter-island: -2.32 ‰). Overall, the benthic community showed similar depletions in δ13C signatures (from -1.96 to -4.70 ‰), suggesting that shifts have occurred in the carbon signatures at the base of the food web. The depletion in δ₁₃C signatures of the benthos at the PEI most likely reflects increased contributions of smaller slow growing phytoplankton cells (more depleted signatures than large fast growing cells) in the diets of these organisms over time. These diet shifts, in turn, suggest a decrease in productivity has occurred at the islands, likely due to a decreased frequency and intensity of the “island mass effect”. Decreased phytoplankton productivity at the PEI likely results from the southward shift in the average position of the sub-Antarctic Front (SAF), most likely in response to climate change, which in turn promotes flow-through conditions rather than retention at the PEI.
- Full Text:
- Date Issued: 2011
Feeding ecology and diet shift of long-beaked common dolphins Delphinus Capensis (Gray 1828) incidentally caught in anti-shark nets off Kwazulu-Natal, South Africa
- Authors: Ambrose, Shan Taryn
- Date: 2011
- Subjects: Common dolphin -- South Africa -- Kwazulu-Natal , Common dolphin -- Food -- South Africa -- Kwazulu-Natal , Common dolphin -- Ecology -- South Africa -- Kwazulu-Natal , Sardinops sagax -- South Africa -- Kwazulu-Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5697 , http://hdl.handle.net/10962/d1005383 , Common dolphin -- South Africa -- Kwazulu-Natal , Common dolphin -- Food -- South Africa -- Kwazulu-Natal , Common dolphin -- Ecology -- South Africa -- Kwazulu-Natal , Sardinops sagax -- South Africa -- Kwazulu-Natal
- Description: The long-beaked common dolphin, Delphinus capensis (Gray 1828), is one of the most enigmatic predators feeding in the annual sardine run (Sardinops sagax) off the coast of KwaZulu-Natal (KZN), South Africa. In recent years, unpredictable inter-annual variations in the timing, spatial extent and intensity of the sardine run have been documented, possibly resulting in changes in the suite of prey available to the common dolphin during winter. Although the diets of a number of predators during the sardine run have been studied in detail (e.g. sharks and flying seabirds), little is known about the diet of long-beaked common dolphins during this period. Each year, a low number of common dolphins are incidentally caught in the anti-shark nets in the waters of KwaZulu-Natal. These captures provide a valuable source of data on selected aspects of the ecology of the long-beaked common dolphins along the KwaZulu-Natal coastline. The objective of this study was to provide new dietary data for the common dolphins feeding in the waters of KwaZulu-Natal during winter over the period 2000 to 2009, as well as to determine if any dietary changes had taken place since the common dolphin diet was last assessed, over 15 years ago. Stomach contents from 95 common dolphins (55 females, 40 males) caught between 2000 and 2009 were analysed and compared to historical data from dolphins caught between 1974 and 1992. Mesopelagic fish and squid dominated the diet, with 23 fish and 5 squid species represented in adult dolphins. Multidimensional Scaling (MDS) indicated that there was no resource partitioning between adult male and female dolphins. Numerical analyses indicated that there was a shift in the principal prey species consumed by the dolphins over the past decade, particularly during the winter. Prior to 1992, sardine comprised up to 49% of the total stomach contents, while chub mackerel (Scomber japonicus) was the dominant prey item (66% by mass) recorded in the stomach contents over the period 2000 to 2009. The shift in the relative contributions of sardine and mackerel in the diets of the dolphin appeared to correspond to fluctuations in the availability of the two principal prey species. Between 2000 and 2009, the diversity of the dolphins' diets was highest during the sardine run, reflecting the presence of a wide suite of predatory teleosts in the waters of KwaZulu-Natal during the annual sardine run. Conversely, prior to 2000, the diet was dominated by sardine during the peak of the sardine run, whilst diet diversity increased after this period. Apart from sardine and chub mackerel, elf (Pomatomus saltatrix), maasbanker (Trachurus delagoa), strepie (Sarpa salpa) and flying fish (Exocoetid sp.) also formed important components of the diet both prior to 1992, and over the last decade. Blubber thickness was assessed as an indicator of animal condition. No significant change in blubber total weight (R² = 0.0016, N = 185), nor dorsal, lateral or ventral blubber thickness (R² = 0.3146, R² = 0.0003, and R² = 0.0003 respectively, N = 78) was seen over the last 30 years (1970 to 2009). Results of stable isotope analyses conducted on tissue derived from the teeth of D. capensis indicated that there has been no significant shift in the trophic position (δ¹⁵N) and potential prey consumed (δ¹³C) over the corresponding period. These data would suggest that the long-beaked common dolphins along the KwaZulu-Natal coastline can be considered as opportunistic predators generally consuming the most abundant prey species available locally. As common dolphins feed opportunistically, this dietary shift appears to indicate changes in the shoaling characteristics of the most abundant fish prey in KwaZulu-Natal during winter. Given the “Data Deficient” status of the long-beaked common dolphin on the IUCN Red Data List, and the strong climatic forcing of the sardine run, such dietary data have important implications for their conservation in the light of expanding fisheries and climate change.
- Full Text:
- Date Issued: 2011
- Authors: Ambrose, Shan Taryn
- Date: 2011
- Subjects: Common dolphin -- South Africa -- Kwazulu-Natal , Common dolphin -- Food -- South Africa -- Kwazulu-Natal , Common dolphin -- Ecology -- South Africa -- Kwazulu-Natal , Sardinops sagax -- South Africa -- Kwazulu-Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5697 , http://hdl.handle.net/10962/d1005383 , Common dolphin -- South Africa -- Kwazulu-Natal , Common dolphin -- Food -- South Africa -- Kwazulu-Natal , Common dolphin -- Ecology -- South Africa -- Kwazulu-Natal , Sardinops sagax -- South Africa -- Kwazulu-Natal
- Description: The long-beaked common dolphin, Delphinus capensis (Gray 1828), is one of the most enigmatic predators feeding in the annual sardine run (Sardinops sagax) off the coast of KwaZulu-Natal (KZN), South Africa. In recent years, unpredictable inter-annual variations in the timing, spatial extent and intensity of the sardine run have been documented, possibly resulting in changes in the suite of prey available to the common dolphin during winter. Although the diets of a number of predators during the sardine run have been studied in detail (e.g. sharks and flying seabirds), little is known about the diet of long-beaked common dolphins during this period. Each year, a low number of common dolphins are incidentally caught in the anti-shark nets in the waters of KwaZulu-Natal. These captures provide a valuable source of data on selected aspects of the ecology of the long-beaked common dolphins along the KwaZulu-Natal coastline. The objective of this study was to provide new dietary data for the common dolphins feeding in the waters of KwaZulu-Natal during winter over the period 2000 to 2009, as well as to determine if any dietary changes had taken place since the common dolphin diet was last assessed, over 15 years ago. Stomach contents from 95 common dolphins (55 females, 40 males) caught between 2000 and 2009 were analysed and compared to historical data from dolphins caught between 1974 and 1992. Mesopelagic fish and squid dominated the diet, with 23 fish and 5 squid species represented in adult dolphins. Multidimensional Scaling (MDS) indicated that there was no resource partitioning between adult male and female dolphins. Numerical analyses indicated that there was a shift in the principal prey species consumed by the dolphins over the past decade, particularly during the winter. Prior to 1992, sardine comprised up to 49% of the total stomach contents, while chub mackerel (Scomber japonicus) was the dominant prey item (66% by mass) recorded in the stomach contents over the period 2000 to 2009. The shift in the relative contributions of sardine and mackerel in the diets of the dolphin appeared to correspond to fluctuations in the availability of the two principal prey species. Between 2000 and 2009, the diversity of the dolphins' diets was highest during the sardine run, reflecting the presence of a wide suite of predatory teleosts in the waters of KwaZulu-Natal during the annual sardine run. Conversely, prior to 2000, the diet was dominated by sardine during the peak of the sardine run, whilst diet diversity increased after this period. Apart from sardine and chub mackerel, elf (Pomatomus saltatrix), maasbanker (Trachurus delagoa), strepie (Sarpa salpa) and flying fish (Exocoetid sp.) also formed important components of the diet both prior to 1992, and over the last decade. Blubber thickness was assessed as an indicator of animal condition. No significant change in blubber total weight (R² = 0.0016, N = 185), nor dorsal, lateral or ventral blubber thickness (R² = 0.3146, R² = 0.0003, and R² = 0.0003 respectively, N = 78) was seen over the last 30 years (1970 to 2009). Results of stable isotope analyses conducted on tissue derived from the teeth of D. capensis indicated that there has been no significant shift in the trophic position (δ¹⁵N) and potential prey consumed (δ¹³C) over the corresponding period. These data would suggest that the long-beaked common dolphins along the KwaZulu-Natal coastline can be considered as opportunistic predators generally consuming the most abundant prey species available locally. As common dolphins feed opportunistically, this dietary shift appears to indicate changes in the shoaling characteristics of the most abundant fish prey in KwaZulu-Natal during winter. Given the “Data Deficient” status of the long-beaked common dolphin on the IUCN Red Data List, and the strong climatic forcing of the sardine run, such dietary data have important implications for their conservation in the light of expanding fisheries and climate change.
- Full Text:
- Date Issued: 2011
A case study of the implementation of science process skills for grades 4 to 7 learners in natural sciences in a South African primary school
- Authors: Ambross, Johannes Nikolaas
- Date: 2011
- Subjects: Science -- Study and teaching (Primary) , Science -- Study and teaching -- South Africa -- Port Elizabeth -- Evaluation , Education -- Evaluation
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9501 , http://hdl.handle.net/10948/1411 , Science -- Study and teaching (Primary) , Science -- Study and teaching -- South Africa -- Port Elizabeth -- Evaluation , Education -- Evaluation
- Description: With the publication of the National Curriculum Statement (2002) (NCS) the use and development of science process skills have become a critical part of the teaching and learning of the Natural Sciences in South Africa. This study sought to evaluate the implementation and development of these basic skills by four grade 4-7 educators at classroom level at a primary school in the northern areas of Port Elizabeth. Qualitative data for this evaluation were collected through educator interviews, classroom observation as well as a focus-group interview. Quantitative data were gathered by means of a Science Process Skills Observation Scale and through examining the learners' assessment activities. An Assessment Activity Science Process Skill Rating-Scale was used to evaluate assessment activities. Data generated from this study were carefully analysed and on the basis of their interpretation it was concluded that the implementation and development of science process skills were strongly influenced by the educators' understanding of these basic concepts, the belief held by each educator about their role and how their learners learn, the presence of quality support and effective training programmes as well continuous professional development.
- Full Text:
- Date Issued: 2011
- Authors: Ambross, Johannes Nikolaas
- Date: 2011
- Subjects: Science -- Study and teaching (Primary) , Science -- Study and teaching -- South Africa -- Port Elizabeth -- Evaluation , Education -- Evaluation
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9501 , http://hdl.handle.net/10948/1411 , Science -- Study and teaching (Primary) , Science -- Study and teaching -- South Africa -- Port Elizabeth -- Evaluation , Education -- Evaluation
- Description: With the publication of the National Curriculum Statement (2002) (NCS) the use and development of science process skills have become a critical part of the teaching and learning of the Natural Sciences in South Africa. This study sought to evaluate the implementation and development of these basic skills by four grade 4-7 educators at classroom level at a primary school in the northern areas of Port Elizabeth. Qualitative data for this evaluation were collected through educator interviews, classroom observation as well as a focus-group interview. Quantitative data were gathered by means of a Science Process Skills Observation Scale and through examining the learners' assessment activities. An Assessment Activity Science Process Skill Rating-Scale was used to evaluate assessment activities. Data generated from this study were carefully analysed and on the basis of their interpretation it was concluded that the implementation and development of science process skills were strongly influenced by the educators' understanding of these basic concepts, the belief held by each educator about their role and how their learners learn, the presence of quality support and effective training programmes as well continuous professional development.
- Full Text:
- Date Issued: 2011
Paper bridges: a critical examination of the Daily Dispatch's ‘community dialogues’
- Authors: Amner, Roderick J
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142645 , vital:38098 , https://doi.org/10.1080/02560054.2011.545564
- Description: A series of town-hall-like meetings called the ‘community dialogues’ were conducted in 2009 by the Daily Dispatch newspaper in East London, under the banner of public/civic journalism, a global journalistic reform movement begun in the United States in the late 1980s. the editorial leadership of the newspaper imagined a number of core journalistic and civic purposes for the dialogues and succeeded in achieving some of these. However, the newspaper's claim that the dialogues could help to build ‘horizontal bridges’ between diverse communities in East London is critically examined through the example of two community dialogues which took place in neighbouring locations - the predominantly white, middle-class suburb of Beacon Bay, and the informal African settlement of Nompumelelo - on consecutive days in 2009. This article argues that social inequalities, particularly acute in the South African context, may preclude the emergence of a shared vision of the common good, and that joint deliberation between diverse social groups in the pursuit of consensus may not be realistic or even an appropriate goal, especially if it means ratifying an unjust status quo.
- Full Text:
- Date Issued: 2011
- Authors: Amner, Roderick J
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142645 , vital:38098 , https://doi.org/10.1080/02560054.2011.545564
- Description: A series of town-hall-like meetings called the ‘community dialogues’ were conducted in 2009 by the Daily Dispatch newspaper in East London, under the banner of public/civic journalism, a global journalistic reform movement begun in the United States in the late 1980s. the editorial leadership of the newspaper imagined a number of core journalistic and civic purposes for the dialogues and succeeded in achieving some of these. However, the newspaper's claim that the dialogues could help to build ‘horizontal bridges’ between diverse communities in East London is critically examined through the example of two community dialogues which took place in neighbouring locations - the predominantly white, middle-class suburb of Beacon Bay, and the informal African settlement of Nompumelelo - on consecutive days in 2009. This article argues that social inequalities, particularly acute in the South African context, may preclude the emergence of a shared vision of the common good, and that joint deliberation between diverse social groups in the pursuit of consensus may not be realistic or even an appropriate goal, especially if it means ratifying an unjust status quo.
- Full Text:
- Date Issued: 2011
Where leaders learn: constructions of leadership and leadership development at Rhodes University
- Authors: Andrews, Rushda Ruth
- Date: 2011
- Subjects: Leadership -- Education (Higher) -- South Africa -- Grahamstown Leadership -- Research -- South Africa -- Grahamstown Development leadership -- Education (Higher) -- South Africa -- Grahamstown Rhodes University -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:782 , http://hdl.handle.net/10962/d1003903
- Description: This thesis explores the Where Leaders Learn slogan of Rhodes University. It does this by means of an analysis of discourses constructing leadership and leadership development within the institutional context. The discourse analysis was made possible as a result of interviews with a range of people involved in leadership and leadership development at the University. The analysis revealed that leadership development is constructed as taking place within a highly structured system that enables instructional and managerial leadership but constrains transformational leadership. The discourses that give meaning and understanding to the construct of leadership draw heavily on position within a hierarchy. The discourse of functional efficiency is enabled through practices related to reward, recognition, succession planning and mentorship which all serve to replicate the existing leadership structures creating more of the same and in essence stifling the potential for emancipatory leadership. The analysis also shows that a discourse of collegiality serves to create a false sense of a common understanding of leadership in the light of evidence of uncertainty and contestation around the meaning of the slogan Where Leaders Learn and, by association, the very construct of leadership. The discursive process of understanding leadership and developing an institutional theory for the purposes of infusing this into a curriculum poses many challenges. Barriers to new ways of thinking reside within the researchers' ontological and epistemological commitments. This amplifies the need for a more reflective ontology towards leadership and its consequences, especially so in a multidisciplinary environment such as Rhodes University.
- Full Text:
- Date Issued: 2011
- Authors: Andrews, Rushda Ruth
- Date: 2011
- Subjects: Leadership -- Education (Higher) -- South Africa -- Grahamstown Leadership -- Research -- South Africa -- Grahamstown Development leadership -- Education (Higher) -- South Africa -- Grahamstown Rhodes University -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:782 , http://hdl.handle.net/10962/d1003903
- Description: This thesis explores the Where Leaders Learn slogan of Rhodes University. It does this by means of an analysis of discourses constructing leadership and leadership development within the institutional context. The discourse analysis was made possible as a result of interviews with a range of people involved in leadership and leadership development at the University. The analysis revealed that leadership development is constructed as taking place within a highly structured system that enables instructional and managerial leadership but constrains transformational leadership. The discourses that give meaning and understanding to the construct of leadership draw heavily on position within a hierarchy. The discourse of functional efficiency is enabled through practices related to reward, recognition, succession planning and mentorship which all serve to replicate the existing leadership structures creating more of the same and in essence stifling the potential for emancipatory leadership. The analysis also shows that a discourse of collegiality serves to create a false sense of a common understanding of leadership in the light of evidence of uncertainty and contestation around the meaning of the slogan Where Leaders Learn and, by association, the very construct of leadership. The discursive process of understanding leadership and developing an institutional theory for the purposes of infusing this into a curriculum poses many challenges. Barriers to new ways of thinking reside within the researchers' ontological and epistemological commitments. This amplifies the need for a more reflective ontology towards leadership and its consequences, especially so in a multidisciplinary environment such as Rhodes University.
- Full Text:
- Date Issued: 2011