A Framework for DNS Based Detection of Botnets at the ISP Level
- Stalmans, Etienne, Irwin, Barry V W
- Authors: Stalmans, Etienne , Irwin, Barry V W
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427984 , vital:72478 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622932_A_Framework_for_DNS_Based_Detection_of_Botnets_at_the_ISP_Level/links/5b9a14e1458515310583fc19/A-Framework-for-DNS-Based-Detection-of-Botnets-at-the-ISP-Level.pdf
- Description: The rapid expansion of networks and increase in internet connected devices has lead to a large number of hosts susceptible to virus infec-tion. Infected hosts are controlled by attackers and form so called bot-nets. These botnets are used to steal data, mask malicious activity and perform distributed denial of service attacks. Traditional protection mechanisms rely on host based detection of viruses. These systems are failing due to the rapid increase in the number of vulnerable hosts and attacks that easily bypass detection mechanisms. This paper pro-poses moving protection from the individual hosts to the Internet Ser-vice Provider (ISP), allowing for the detection and prevention of botnet traffic. DNS traffic inspection allows for the development of a lightweight and accurate classifier that has little or no effect on network perfor-mance. By preventing botnet activity at the ISP level, it is hoped that the threat of botnets can largely be mitigated.
- Full Text:
- Authors: Stalmans, Etienne , Irwin, Barry V W
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427984 , vital:72478 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622932_A_Framework_for_DNS_Based_Detection_of_Botnets_at_the_ISP_Level/links/5b9a14e1458515310583fc19/A-Framework-for-DNS-Based-Detection-of-Botnets-at-the-ISP-Level.pdf
- Description: The rapid expansion of networks and increase in internet connected devices has lead to a large number of hosts susceptible to virus infec-tion. Infected hosts are controlled by attackers and form so called bot-nets. These botnets are used to steal data, mask malicious activity and perform distributed denial of service attacks. Traditional protection mechanisms rely on host based detection of viruses. These systems are failing due to the rapid increase in the number of vulnerable hosts and attacks that easily bypass detection mechanisms. This paper pro-poses moving protection from the individual hosts to the Internet Ser-vice Provider (ISP), allowing for the detection and prevention of botnet traffic. DNS traffic inspection allows for the development of a lightweight and accurate classifier that has little or no effect on network perfor-mance. By preventing botnet activity at the ISP level, it is hoped that the threat of botnets can largely be mitigated.
- Full Text:
A framework for the application of network telescope sensors in a global IP network
- Authors: Irwin, Barry Vivian William
- Date: 2011
- Subjects: Sensor networks Computer networks TCP/IP (Computer network protocol) Internet Computer security Computers -- Access control Computer networks -- Security measures Computer viruses Malware (Computer software)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4593 , http://hdl.handle.net/10962/d1004835
- Description: The use of Network Telescope systems has become increasingly popular amongst security researchers in recent years. This study provides a framework for the utilisation of this data. The research is based on a primary dataset of 40 million events spanning 50 months collected using a small (/24) passive network telescope located in African IP space. This research presents a number of differing ways in which the data can be analysed ranging from low level protocol based analysis to higher level analysis at the geopolitical and network topology level. Anomalous traffic and illustrative anecdotes are explored in detail and highlighted. A discussion relating to bogon traffic observed is also presented. Two novel visualisation tools are presented, which were developed to aid in the analysis of large network telescope datasets. The first is a three-dimensional visualisation tool which allows for live, near-realtime analysis, and the second is a two-dimensional fractal based plotting scheme which allows for plots of the entire IPv4 address space to be produced, and manipulated. Using the techniques and tools developed for the analysis of this dataset, a detailed analysis of traffic recorded as destined for port 445/tcp is presented. This includes the evaluation of traffic surrounding the outbreak of the Conficker worm in November 2008. A number of metrics relating to the description and quantification of network telescope configuration and the resultant traffic captures are described, the use of which it is hoped will facilitate greater and easier collaboration among researchers utilising this network security technology. The research concludes with suggestions relating to other applications of the data and intelligence that can be extracted from network telescopes, and their use as part of an organisation’s integrated network security systems
- Full Text:
- Authors: Irwin, Barry Vivian William
- Date: 2011
- Subjects: Sensor networks Computer networks TCP/IP (Computer network protocol) Internet Computer security Computers -- Access control Computer networks -- Security measures Computer viruses Malware (Computer software)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4593 , http://hdl.handle.net/10962/d1004835
- Description: The use of Network Telescope systems has become increasingly popular amongst security researchers in recent years. This study provides a framework for the utilisation of this data. The research is based on a primary dataset of 40 million events spanning 50 months collected using a small (/24) passive network telescope located in African IP space. This research presents a number of differing ways in which the data can be analysed ranging from low level protocol based analysis to higher level analysis at the geopolitical and network topology level. Anomalous traffic and illustrative anecdotes are explored in detail and highlighted. A discussion relating to bogon traffic observed is also presented. Two novel visualisation tools are presented, which were developed to aid in the analysis of large network telescope datasets. The first is a three-dimensional visualisation tool which allows for live, near-realtime analysis, and the second is a two-dimensional fractal based plotting scheme which allows for plots of the entire IPv4 address space to be produced, and manipulated. Using the techniques and tools developed for the analysis of this dataset, a detailed analysis of traffic recorded as destined for port 445/tcp is presented. This includes the evaluation of traffic surrounding the outbreak of the Conficker worm in November 2008. A number of metrics relating to the description and quantification of network telescope configuration and the resultant traffic captures are described, the use of which it is hoped will facilitate greater and easier collaboration among researchers utilising this network security technology. The research concludes with suggestions relating to other applications of the data and intelligence that can be extracted from network telescopes, and their use as part of an organisation’s integrated network security systems
- Full Text:
A Framework for the Management of Operator Policies and User Preferences for Service Compositions in the IP Multimedia Subsystem
- Tsietsi, Mosiuoa, Terzoli, Alfredo, Wells, George C
- Authors: Tsietsi, Mosiuoa , Terzoli, Alfredo , Wells, George C
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430680 , vital:72708 , https://ieeexplore.ieee.org/abstract/document/6032212
- Description: The IP Multimedia Subsystem (IMS) is a telecommunication middleware platform with robust service features that enables the delivery of a wide range of services to mobile network subscribers. Network operators are encouraged to develop services from service building blocks in order to avoid redundancies by re-using existing functionality. In this environ-ment, operators must be able to control the service execution chain in order to prevent undesirable interactions from occurring between indi-vidual building blocks. It is also in their interests to provide subscribers with personalisation options so that they can modify service composi-tions and define their own preferences for how they would like their ser-vices to behave during live sessions. This paper describes a solution for these challenges that involves the storage of service information in an XDMS and allows operator staff and subscribers to manage this in-formation using the XCAP protocol. The ETSI-defined XCAP applica-tion usage named simservs was chosen to demonstrate an application usage that can be used to create service compositions in XML format. A prototype is described that uses components of the open source Mo-bicents project to verify the suitability of the design. This work is part of a larger effort aimed at modeling interaction management in the IMS through the use of a service broker that is part of an extended IMS ser-vice layer (EISL). The service broker's functional and structural architec-ture have not yet been standardised.
- Full Text:
- Authors: Tsietsi, Mosiuoa , Terzoli, Alfredo , Wells, George C
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430680 , vital:72708 , https://ieeexplore.ieee.org/abstract/document/6032212
- Description: The IP Multimedia Subsystem (IMS) is a telecommunication middleware platform with robust service features that enables the delivery of a wide range of services to mobile network subscribers. Network operators are encouraged to develop services from service building blocks in order to avoid redundancies by re-using existing functionality. In this environ-ment, operators must be able to control the service execution chain in order to prevent undesirable interactions from occurring between indi-vidual building blocks. It is also in their interests to provide subscribers with personalisation options so that they can modify service composi-tions and define their own preferences for how they would like their ser-vices to behave during live sessions. This paper describes a solution for these challenges that involves the storage of service information in an XDMS and allows operator staff and subscribers to manage this in-formation using the XCAP protocol. The ETSI-defined XCAP applica-tion usage named simservs was chosen to demonstrate an application usage that can be used to create service compositions in XML format. A prototype is described that uses components of the open source Mo-bicents project to verify the suitability of the design. This work is part of a larger effort aimed at modeling interaction management in the IMS through the use of a service broker that is part of an extended IMS ser-vice layer (EISL). The service broker's functional and structural architec-ture have not yet been standardised.
- Full Text:
A fuzz testing framework for evaluating and securing network applications
- Zeisberger, Sascha, Irwin, Barry V W
- Authors: Zeisberger, Sascha , Irwin, Barry V W
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428000 , vital:72479 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622655_A_Fuzz_Testing_Framework_for_Evaluating_and_Securing_Network_Applications/links/5b9a153b92851c4ba8181b0d/A-Fuzz-Testing-Framework-for-Evaluating-and-Securing-Network-Applications.pdf
- Description: Research has shown that fuzz-testing is an effective means of increasing the quality and security of software and systems. This project proposes the im-plementation of a testing framework based on numerous fuzz-testing tech-niques. The framework will allow a user to detect errors in applications and locate critical areas in the applications that are responsible for the detected errors. The aim is to provide an all-encompassing testing framework that will allow a developer to quickly and effectively deploy fuzz tests on an applica-tion and ensure a higher level of quality control before deployment.
- Full Text:
- Authors: Zeisberger, Sascha , Irwin, Barry V W
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428000 , vital:72479 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622655_A_Fuzz_Testing_Framework_for_Evaluating_and_Securing_Network_Applications/links/5b9a153b92851c4ba8181b0d/A-Fuzz-Testing-Framework-for-Evaluating-and-Securing-Network-Applications.pdf
- Description: Research has shown that fuzz-testing is an effective means of increasing the quality and security of software and systems. This project proposes the im-plementation of a testing framework based on numerous fuzz-testing tech-niques. The framework will allow a user to detect errors in applications and locate critical areas in the applications that are responsible for the detected errors. The aim is to provide an all-encompassing testing framework that will allow a developer to quickly and effectively deploy fuzz tests on an applica-tion and ensure a higher level of quality control before deployment.
- Full Text:
A learning state?: a case study of the post-1994 South African welfare regime
- Mungwashu, Sthembiso Handinawangu
- Authors: Mungwashu, Sthembiso Handinawangu
- Date: 2011
- Subjects: South African Social Security Agency , South Africa -- Social policy , Poor -- South Africa , Social service -- South Africa , Public welfare -- South Africa , Social service -- Government policy -- South Africa
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3325 , http://hdl.handle.net/10962/d1003113 , South African Social Security Agency , South Africa -- Social policy , Poor -- South Africa , Social service -- South Africa , Public welfare -- South Africa , Social service -- Government policy -- South Africa
- Description: This thesis examines the processes of policymaking in South Africa, as expressed through the shifts in income maintenance policy. The thesis focuses on the processes leading to the establishment of the South African Social Security Agency (SASSA), as its case study. SASSA is the institutional framework for the delivery of social grants. Our intention is to test the efficacy of what we have called ‘state learning’ in the South African context. Therefore, the overall aim of the study is to assess the capacity of the ‘state to learn’ in the process of policymaking as expressed through the shifts in social grant administration and the institutional framework of social welfare in South Africa. The subsidiary goals of the research includes mapping changes in the system of social grants administration since 1994 in order to assess the sources of the shifts in its institutional framework; to assess processes and responses within the state that result in policy shifts and the extent to which these can be considered dimensions of state learning; to assess the power of ideas in the policymaking process and to assess the influence of non-state agencies/actors in policy contestation and learning processes. This is essential, because social policy, especially welfare policy research in post-apartheid South Africa, has focused on the economic value of policies and not the political processes in policymaking. For the framework of analysis the study draws on theories of learning, especially at the organizational or institutional level. We start from the perspective that policymaking and implementation cannot be reduced to a neatly ordered schema (Lamb: 1987:6). Further, that policy change and policymaking are “iterative, haphazard, and highly political processes, in which the apparently logical sequences of decision-making, may turn out to be the reverse” (Lamb, 1987:6). This is mainly because state building is a complex affair and a contested terrain; policy learning and making are neither benign nor do they involve the state working in isolation (Sabatier, 1998). To understand processes of policymaking in South Africa, we rely on content analysis of primary and secondary materials or documents and in-depth interviews with key informants involved in the policy process. The documentary sources include records of parliamentary debates, green and white papers on social welfare, ANC party documents, presidential task force reports, newspapers, magazines and court judgments. The study reveals that the establishment of SASSA lends itself to the idea of ‘state learning’. Learning is indicated in South Africa by the capacity and ability of the state to stimulate ideas, debate ideas to establish ideational matrixes as well as paradigms that have informed the development of policy, take ideas and implement them to try and solve mismatches between the intention of the state and the outcomes and the ability of the state to produce policy.
- Full Text:
- Authors: Mungwashu, Sthembiso Handinawangu
- Date: 2011
- Subjects: South African Social Security Agency , South Africa -- Social policy , Poor -- South Africa , Social service -- South Africa , Public welfare -- South Africa , Social service -- Government policy -- South Africa
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3325 , http://hdl.handle.net/10962/d1003113 , South African Social Security Agency , South Africa -- Social policy , Poor -- South Africa , Social service -- South Africa , Public welfare -- South Africa , Social service -- Government policy -- South Africa
- Description: This thesis examines the processes of policymaking in South Africa, as expressed through the shifts in income maintenance policy. The thesis focuses on the processes leading to the establishment of the South African Social Security Agency (SASSA), as its case study. SASSA is the institutional framework for the delivery of social grants. Our intention is to test the efficacy of what we have called ‘state learning’ in the South African context. Therefore, the overall aim of the study is to assess the capacity of the ‘state to learn’ in the process of policymaking as expressed through the shifts in social grant administration and the institutional framework of social welfare in South Africa. The subsidiary goals of the research includes mapping changes in the system of social grants administration since 1994 in order to assess the sources of the shifts in its institutional framework; to assess processes and responses within the state that result in policy shifts and the extent to which these can be considered dimensions of state learning; to assess the power of ideas in the policymaking process and to assess the influence of non-state agencies/actors in policy contestation and learning processes. This is essential, because social policy, especially welfare policy research in post-apartheid South Africa, has focused on the economic value of policies and not the political processes in policymaking. For the framework of analysis the study draws on theories of learning, especially at the organizational or institutional level. We start from the perspective that policymaking and implementation cannot be reduced to a neatly ordered schema (Lamb: 1987:6). Further, that policy change and policymaking are “iterative, haphazard, and highly political processes, in which the apparently logical sequences of decision-making, may turn out to be the reverse” (Lamb, 1987:6). This is mainly because state building is a complex affair and a contested terrain; policy learning and making are neither benign nor do they involve the state working in isolation (Sabatier, 1998). To understand processes of policymaking in South Africa, we rely on content analysis of primary and secondary materials or documents and in-depth interviews with key informants involved in the policy process. The documentary sources include records of parliamentary debates, green and white papers on social welfare, ANC party documents, presidential task force reports, newspapers, magazines and court judgments. The study reveals that the establishment of SASSA lends itself to the idea of ‘state learning’. Learning is indicated in South Africa by the capacity and ability of the state to stimulate ideas, debate ideas to establish ideational matrixes as well as paradigms that have informed the development of policy, take ideas and implement them to try and solve mismatches between the intention of the state and the outcomes and the ability of the state to produce policy.
- Full Text:
A legal-comparative study of the interpretation and application of the doctrines of the sham and the alter-ego in the context of South African trust law: the dangers of translocating company law principles into trust law
- Authors: Stafford, Rowan Bell
- Date: 2011
- Subjects: Trusts and trustees -- South Africa , Equity -- South Africa , Law reform -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3695 , http://hdl.handle.net/10962/d1003210 , Trusts and trustees -- South Africa , Equity -- South Africa , Law reform -- South Africa
- Description: This thesis analyses the doctrines of the sham and the alter-ego and their application to the law of trusts in South Africa. Following an initial examination of the historical development of the law of trusts in English law and the principles of equity law, the study focuses on the current legal status of the trust inter vivos in South Africa and the similarities to its English forerunner. The work traces the sham doctrine back to its origins in English law, where the term “sham” was first used in the context of fraud and dishonesty in cases involving matters arising from hire-purchase agreements, and explains how it gradually began to find its place in the law of trusts. During the exploration, the work highlights the cornerstone of the sham doctrine’s development, the Snook test, which in effect became the internationally accepted guideline for any sham trust enquiry. In terms of the alter-ego doctrine, the work highlights the birth of the principle in Australian law and the doctrine’s immediate reception into other common law jurisdictions and its resultant development. The growth, maturity and popularity of the doctrines are key to the thesis and, in the course of the investigation, the study provides a legal-comparative analysis of the treatment of the doctrines in the context of trusts against that in other common law countries. The study then shifts its focus to South Africa’s interpretation and application of these doctrines in trust law, and reveals the erroneous judicial development in which the courts have in some instances mistakenly replaced the sham doctrine with the company law doctrine of piercing the corporate veil or, in other instances, have erroneously conflated the two trust doctrines. The results highlight a breach of a fundamental rule observed overseas – the “no half way house” rule, which specifically cautions against South Africa’s chosen direction when allowing the lifting of a trust’s veil. The study closes with suggestions as to how the country could reconcile the problems underlined in the thesis by means of law reform, as well as offering practical advice for settlors, trustees and beneficiaries, the core of which is given in the handbook that accompanies this thesis.
- Full Text:
- Authors: Stafford, Rowan Bell
- Date: 2011
- Subjects: Trusts and trustees -- South Africa , Equity -- South Africa , Law reform -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3695 , http://hdl.handle.net/10962/d1003210 , Trusts and trustees -- South Africa , Equity -- South Africa , Law reform -- South Africa
- Description: This thesis analyses the doctrines of the sham and the alter-ego and their application to the law of trusts in South Africa. Following an initial examination of the historical development of the law of trusts in English law and the principles of equity law, the study focuses on the current legal status of the trust inter vivos in South Africa and the similarities to its English forerunner. The work traces the sham doctrine back to its origins in English law, where the term “sham” was first used in the context of fraud and dishonesty in cases involving matters arising from hire-purchase agreements, and explains how it gradually began to find its place in the law of trusts. During the exploration, the work highlights the cornerstone of the sham doctrine’s development, the Snook test, which in effect became the internationally accepted guideline for any sham trust enquiry. In terms of the alter-ego doctrine, the work highlights the birth of the principle in Australian law and the doctrine’s immediate reception into other common law jurisdictions and its resultant development. The growth, maturity and popularity of the doctrines are key to the thesis and, in the course of the investigation, the study provides a legal-comparative analysis of the treatment of the doctrines in the context of trusts against that in other common law countries. The study then shifts its focus to South Africa’s interpretation and application of these doctrines in trust law, and reveals the erroneous judicial development in which the courts have in some instances mistakenly replaced the sham doctrine with the company law doctrine of piercing the corporate veil or, in other instances, have erroneously conflated the two trust doctrines. The results highlight a breach of a fundamental rule observed overseas – the “no half way house” rule, which specifically cautions against South Africa’s chosen direction when allowing the lifting of a trust’s veil. The study closes with suggestions as to how the country could reconcile the problems underlined in the thesis by means of law reform, as well as offering practical advice for settlors, trustees and beneficiaries, the core of which is given in the handbook that accompanies this thesis.
- Full Text:
a pH-metric speciation and anti-diabetic study of oxovanadium (IV) amino acid derivatives
- Authors: Gundhla, Isaac Zvikomborero
- Date: 2011 , 2011-03-15
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4399 , http://hdl.handle.net/10962/d1006691
- Description: Novel oxovanadium(IV) complexes of glycine, ʟ-alanine, 1-methylimidazole-2-carboxylic acid, imidazole-2-caboxylic acid and imidazole-4-carboxylic acid were synthesized and isolated in the solid state. The ligands and complexes were characterized by elemental analysis, melting point, NMR, IR and UV-vis spectroscopy. The IR studies showed that glycine and ʟ-alanine coordinate monodentately through the amine nitrogen whilst the imidazole-carboxylic acid derivatives assume a bidentate chelation. The electronic spectroscopic studies indicate distorted octahedral geometry for the oxovanadium complexes of amino acids and a square pyramidal geometry for oxovanadium(IV) complexes of imidazole carboxylic acid derivatives. The reaction of vanadyl (VO2+) with glycine, ʟ-alanine, imidazole-2-cabrboxylic acid, imidazole-4-carboxylic acid and 1-methylimidazole-2-carboxylic acid was studied in aqueous solution by pH-potentiometry under oxygen and carbon dioxide-free conditions. The data obtained from these titrations were used to calculate the protonation and stability constants. The results showed that all ligands are suitable for bidentate coordination in the formation of monomeric species although the solid state studies of the oxovanadium(IV) complexes of amino acids showed a monodentate coordination. The overall stability constants for the (VIVO)-ʟ-alanine system (log β120 = 18.27(6)), (VIVO)-glycine system (β120 = 17.22(6)), (VIVO)-imidazole-4-carboxyic acid (β120 = 11.38(8)), (VIVO)-imidazole-2-carboxylic acid (β120 = 11.62(6)) and (VIVO)-1-methylimidazole-2-carboxylic acid (β120 = 15.49(9)) were obtained. The calculations for the species distribution in the experimental pH range showed that the neutral bis-coordinated complexes are dominant over the biological pH range. The glucose uptake effect of oxovanadium(IV) complex of ʟ-alanine, imidazole-4-carboxylic acid, imidazole-2-carboxylic acid and 1-methylimidazole-2-carboxylic acid was investigated using 3T3-L1 adipocytes, Chang liver and C2C12 muscle cells at various concentrations. The compounds had significant glucose uptake on Chang liver cells only at a concentration of 0.1-10 μM whilst in the C2C12 muscle and 3T3-L1 cells the compounds showed little to no activity probably due to the lower concentrations employed as a result of the cytotoxicity of these compounds on these two cell lines.
- Full Text:
- Authors: Gundhla, Isaac Zvikomborero
- Date: 2011 , 2011-03-15
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4399 , http://hdl.handle.net/10962/d1006691
- Description: Novel oxovanadium(IV) complexes of glycine, ʟ-alanine, 1-methylimidazole-2-carboxylic acid, imidazole-2-caboxylic acid and imidazole-4-carboxylic acid were synthesized and isolated in the solid state. The ligands and complexes were characterized by elemental analysis, melting point, NMR, IR and UV-vis spectroscopy. The IR studies showed that glycine and ʟ-alanine coordinate monodentately through the amine nitrogen whilst the imidazole-carboxylic acid derivatives assume a bidentate chelation. The electronic spectroscopic studies indicate distorted octahedral geometry for the oxovanadium complexes of amino acids and a square pyramidal geometry for oxovanadium(IV) complexes of imidazole carboxylic acid derivatives. The reaction of vanadyl (VO2+) with glycine, ʟ-alanine, imidazole-2-cabrboxylic acid, imidazole-4-carboxylic acid and 1-methylimidazole-2-carboxylic acid was studied in aqueous solution by pH-potentiometry under oxygen and carbon dioxide-free conditions. The data obtained from these titrations were used to calculate the protonation and stability constants. The results showed that all ligands are suitable for bidentate coordination in the formation of monomeric species although the solid state studies of the oxovanadium(IV) complexes of amino acids showed a monodentate coordination. The overall stability constants for the (VIVO)-ʟ-alanine system (log β120 = 18.27(6)), (VIVO)-glycine system (β120 = 17.22(6)), (VIVO)-imidazole-4-carboxyic acid (β120 = 11.38(8)), (VIVO)-imidazole-2-carboxylic acid (β120 = 11.62(6)) and (VIVO)-1-methylimidazole-2-carboxylic acid (β120 = 15.49(9)) were obtained. The calculations for the species distribution in the experimental pH range showed that the neutral bis-coordinated complexes are dominant over the biological pH range. The glucose uptake effect of oxovanadium(IV) complex of ʟ-alanine, imidazole-4-carboxylic acid, imidazole-2-carboxylic acid and 1-methylimidazole-2-carboxylic acid was investigated using 3T3-L1 adipocytes, Chang liver and C2C12 muscle cells at various concentrations. The compounds had significant glucose uptake on Chang liver cells only at a concentration of 0.1-10 μM whilst in the C2C12 muscle and 3T3-L1 cells the compounds showed little to no activity probably due to the lower concentrations employed as a result of the cytotoxicity of these compounds on these two cell lines.
- Full Text:
A platform for computer-assisted multilingual literacy development
- Authors: Mudimba, Bwini Chizabubi
- Date: 2011
- Subjects: FundaWethu , Language acquisition -- Computer-assisted instruction , Language arts (Elementary) -- Computer-assisted instruction , Language and education , Education, Bilingual , Computer-assisted instruction , Educational technology , Computers and literacy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4600 , http://hdl.handle.net/10962/d1004850 , FundaWethu , Language acquisition -- Computer-assisted instruction , Language arts (Elementary) -- Computer-assisted instruction , Language and education , Education, Bilingual , Computer-assisted instruction , Educational technology , Computers and literacy
- Description: FundaWethu is reading software that is designed to deliver reading lessons to Grade R-3 (foundation phase) children who are learning to read in a multilingual context. Starting from a premise that the system should be both educative and entertaining, the system allows literacy researchers or teachers to construct rich multimedia reading lessons, with text, pictures (possibly animated), and audio files. Using the design-based research methodology which is problem driven and iterative, we followed a user-centred design process in creating FundaWethu. To promote sustainability of the software, we chose to bring teachers on board as “co-designers” using the lesson authoring tool. We made the authoring tool simple enough for use by non computer specialists, but expressive enough to enable a wide range of beginners reading exercises to be constructed in a number of different languages (indigenous South African languages in particular). This project therefore centred on the use of designbased research to build FundaWethu, the design and construction of FundaWethu and the usability study carried out to determine the adequacy of FundaWethu.
- Full Text:
- Authors: Mudimba, Bwini Chizabubi
- Date: 2011
- Subjects: FundaWethu , Language acquisition -- Computer-assisted instruction , Language arts (Elementary) -- Computer-assisted instruction , Language and education , Education, Bilingual , Computer-assisted instruction , Educational technology , Computers and literacy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4600 , http://hdl.handle.net/10962/d1004850 , FundaWethu , Language acquisition -- Computer-assisted instruction , Language arts (Elementary) -- Computer-assisted instruction , Language and education , Education, Bilingual , Computer-assisted instruction , Educational technology , Computers and literacy
- Description: FundaWethu is reading software that is designed to deliver reading lessons to Grade R-3 (foundation phase) children who are learning to read in a multilingual context. Starting from a premise that the system should be both educative and entertaining, the system allows literacy researchers or teachers to construct rich multimedia reading lessons, with text, pictures (possibly animated), and audio files. Using the design-based research methodology which is problem driven and iterative, we followed a user-centred design process in creating FundaWethu. To promote sustainability of the software, we chose to bring teachers on board as “co-designers” using the lesson authoring tool. We made the authoring tool simple enough for use by non computer specialists, but expressive enough to enable a wide range of beginners reading exercises to be constructed in a number of different languages (indigenous South African languages in particular). This project therefore centred on the use of designbased research to build FundaWethu, the design and construction of FundaWethu and the usability study carried out to determine the adequacy of FundaWethu.
- Full Text:
A regulationist approach to South Africa and a critique of inflation targeting
- Authors: Bax, Ryan Michael Jonathan
- Date: 2011
- Subjects: Inflation (Finance) -- South Africa International finance Economic development -- South Africa Sustainable development -- South Africa Inflation targeting -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1036 , http://hdl.handle.net/10962/d1004533
- Description: Since the 1970s, the international economic system has become prone to the volatility and undue effects associated with booms and busts. This forty year period spanning the present has exhibited restrained growth and repressive economic development. Critical changes to the system are presented by the transition from "Fordism" to the post 1970s neoliberal regime and the globalization of world markets. Underpinning this transformation is an ideological shift towards free market capitalism and the adoption of "reduced form" market models. These "reduced form" models appear to hinder economic sustainability as their grounding in economics fails to account for real economic activity. This thesis aims to provide a more holistic perception of sustainability, one that provides a sound basis on which to develop sustainable economic policy. The Regulationist Approach presents the requisite understanding of economic sustainability required within this research. The inclusion of economic, historical and socio-political fields of research proposes a wider understanding of the political economy and sustainability. The application of the Regulation Approach to the South African economy illustrates many problem areas that require attention. The examination found that firstly, aggregate demand in the South African economy was unsustainable due to the debt driven nature of demand under the asset price bubble of the mid to late 2000s. Secondly, aggregate supply also proved unsustainable as government is failing to provide any substantive growth within important sectors of the economy such as education and the provision of general services. Furthermore, the adoption of inflation targeting in South Africa poses a barrier to sustained economic growth as it focuses singularly on price inflation. The "reduced form" model of inflation targeting fails to account for market failures and a number of vital indicators of sustainability most notably, debt levels and asset prices. The inclusion of these indicators, and financial stability more generally, are found to provide a more holistic and sustainable approach to macroeconomic policymaking.
- Full Text:
- Authors: Bax, Ryan Michael Jonathan
- Date: 2011
- Subjects: Inflation (Finance) -- South Africa International finance Economic development -- South Africa Sustainable development -- South Africa Inflation targeting -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1036 , http://hdl.handle.net/10962/d1004533
- Description: Since the 1970s, the international economic system has become prone to the volatility and undue effects associated with booms and busts. This forty year period spanning the present has exhibited restrained growth and repressive economic development. Critical changes to the system are presented by the transition from "Fordism" to the post 1970s neoliberal regime and the globalization of world markets. Underpinning this transformation is an ideological shift towards free market capitalism and the adoption of "reduced form" market models. These "reduced form" models appear to hinder economic sustainability as their grounding in economics fails to account for real economic activity. This thesis aims to provide a more holistic perception of sustainability, one that provides a sound basis on which to develop sustainable economic policy. The Regulationist Approach presents the requisite understanding of economic sustainability required within this research. The inclusion of economic, historical and socio-political fields of research proposes a wider understanding of the political economy and sustainability. The application of the Regulation Approach to the South African economy illustrates many problem areas that require attention. The examination found that firstly, aggregate demand in the South African economy was unsustainable due to the debt driven nature of demand under the asset price bubble of the mid to late 2000s. Secondly, aggregate supply also proved unsustainable as government is failing to provide any substantive growth within important sectors of the economy such as education and the provision of general services. Furthermore, the adoption of inflation targeting in South Africa poses a barrier to sustained economic growth as it focuses singularly on price inflation. The "reduced form" model of inflation targeting fails to account for market failures and a number of vital indicators of sustainability most notably, debt levels and asset prices. The inclusion of these indicators, and financial stability more generally, are found to provide a more holistic and sustainable approach to macroeconomic policymaking.
- Full Text:
A research tool for analysing and monitoring the Extent to which Environmental issues are integrated into teachers’ lessons
- Authors: Nsubuga, Yvonne
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/386447 , vital:68142 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122246"
- Description: South Africa enjoys strong policy support for the integration of environmental issues into school curricula. However, much doubt exists over the extent to which this has been converted into appropriate classroom practice at the majority of under-resourced rural schools in the country. This article reports on a study which piloted a research tool which can be used to analyse teachers’ lessons, with the aim of gaining insight into the extent to which they integrate natural resource management issues. The research tool was based on Bernstein’s concept of classification and consisted of five indicators of natural resource management integration into Life Sciences lessons. The study contributes to the design of research tools that can be used to analyse and monitor the integration of environmental issues into teachers’ lessons. It also provides some insight into the environmental content of a sample of Grade 10 Life Sciences lessons at four rural underresourced schools in the Eastern Cape.
- Full Text:
- Authors: Nsubuga, Yvonne
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/386447 , vital:68142 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122246"
- Description: South Africa enjoys strong policy support for the integration of environmental issues into school curricula. However, much doubt exists over the extent to which this has been converted into appropriate classroom practice at the majority of under-resourced rural schools in the country. This article reports on a study which piloted a research tool which can be used to analyse teachers’ lessons, with the aim of gaining insight into the extent to which they integrate natural resource management issues. The research tool was based on Bernstein’s concept of classification and consisted of five indicators of natural resource management integration into Life Sciences lessons. The study contributes to the design of research tools that can be used to analyse and monitor the integration of environmental issues into teachers’ lessons. It also provides some insight into the environmental content of a sample of Grade 10 Life Sciences lessons at four rural underresourced schools in the Eastern Cape.
- Full Text:
A review of marine phylogeography in southern Africa
- Teske, Peter R, Von der Heyden, Sophie, McQuaid, Christopher D, Barker, Nigel P
- Authors: Teske, Peter R , Von der Heyden, Sophie , McQuaid, Christopher D , Barker, Nigel P
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445392 , vital:74382 , https://hdl.handle.net/10520/EJC97146
- Description: The southern African marine realm is located at the transition zone between the Atlantic and Indo-Pacific biomes. Its biodiversity is particularly rich and comprises faunal and floral elements from the two major oceanic regions, as well as a large number of endemics. Within this realm, strikingly different biota occur in close geographic proximity to each other, and many of the species with distributions spanning two or more of the region's marine biogeographic provinces are divided into evolutionary units that can often only be distinguished on the basis of genetic data. In this review, we describe the state of marine phylogeography in southern Africa, that is, the study of evolutionary relationships at the species level, or amongst closely related species, in relation to the region's marine environment. We focus particularly on coastal phylogeography, where much progress has recently been made in identifying phylogeographic breaks and explaining how they originated and are maintained. We also highlight numerous shortcomings that should be addressed in the near future. These include: the limited data available for commercially important organisms, particularly offshore species; the paucity of oceanographic data for nearshore areas; a dearth of studies based on multilocus data; and the fact that studying the role of diversifying selection in speciation has been limited to physiological approaches to the exclusion of genetics. It is becoming apparent that the southern African marine realm is one of the world's most interesting environments in which to study the evolutionary processes that shape not only regional, but also global patterns of marine biodiversity.
- Full Text:
- Authors: Teske, Peter R , Von der Heyden, Sophie , McQuaid, Christopher D , Barker, Nigel P
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445392 , vital:74382 , https://hdl.handle.net/10520/EJC97146
- Description: The southern African marine realm is located at the transition zone between the Atlantic and Indo-Pacific biomes. Its biodiversity is particularly rich and comprises faunal and floral elements from the two major oceanic regions, as well as a large number of endemics. Within this realm, strikingly different biota occur in close geographic proximity to each other, and many of the species with distributions spanning two or more of the region's marine biogeographic provinces are divided into evolutionary units that can often only be distinguished on the basis of genetic data. In this review, we describe the state of marine phylogeography in southern Africa, that is, the study of evolutionary relationships at the species level, or amongst closely related species, in relation to the region's marine environment. We focus particularly on coastal phylogeography, where much progress has recently been made in identifying phylogeographic breaks and explaining how they originated and are maintained. We also highlight numerous shortcomings that should be addressed in the near future. These include: the limited data available for commercially important organisms, particularly offshore species; the paucity of oceanographic data for nearshore areas; a dearth of studies based on multilocus data; and the fact that studying the role of diversifying selection in speciation has been limited to physiological approaches to the exclusion of genetics. It is becoming apparent that the southern African marine realm is one of the world's most interesting environments in which to study the evolutionary processes that shape not only regional, but also global patterns of marine biodiversity.
- Full Text:
A revision of the Pyura stolonifera species complex (Tunicata, Ascidiacea), with a description of a new species from Australia
- Authors: Teske, Peter R , Ruis, Marc
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445654 , vital:74411 , https://www.biotaxa.org/Zootaxa/article/view/zootaxa.2754.1.2
- Description: Pyura stolonifera is a large solitary ascidian found in Africa, Australasia and South America. The taxonomic status of different populations of this species is disputed, especially since there is evidence for several distinct morphological and genetic units that point towards the existence of multiple cryptic species. While some researchers still recognize P. stolonifera as a single species, others treat the different populations as distinct species. Here, we present a revision of the P. stolonifera species complex based on the examination of samples from all regions where there are reliable reports of this taxon. We recognize four species that are both morphologically and genetically distinct, one of which is new to science and is formally described here. This species is morphologically distinct from the other three members of the species complex in terms of the colour and texture of the tunic, the arrangement of the gonads within the gut and the shape of the dorsal tubercle, among other characters. We name the new species Pyura dalbyi after Dr. J.E. Dalby Jr., whose research on its ecology and distribution provided the incentive for examining this species more closely.
- Full Text:
- Authors: Teske, Peter R , Ruis, Marc
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445654 , vital:74411 , https://www.biotaxa.org/Zootaxa/article/view/zootaxa.2754.1.2
- Description: Pyura stolonifera is a large solitary ascidian found in Africa, Australasia and South America. The taxonomic status of different populations of this species is disputed, especially since there is evidence for several distinct morphological and genetic units that point towards the existence of multiple cryptic species. While some researchers still recognize P. stolonifera as a single species, others treat the different populations as distinct species. Here, we present a revision of the P. stolonifera species complex based on the examination of samples from all regions where there are reliable reports of this taxon. We recognize four species that are both morphologically and genetically distinct, one of which is new to science and is formally described here. This species is morphologically distinct from the other three members of the species complex in terms of the colour and texture of the tunic, the arrangement of the gonads within the gut and the shape of the dorsal tubercle, among other characters. We name the new species Pyura dalbyi after Dr. J.E. Dalby Jr., whose research on its ecology and distribution provided the incentive for examining this species more closely.
- Full Text:
A Search for Conjunctions at a Time of Direction-setting Review and Synthesis
- Authors: O'Donoghue, Rob B
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/387134 , vital:68209 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122240"
- Description: This journal reflects a diversity of environment and sustainability education research and viewpoints alongside two synthesis papers. Read as a whole and within a widely held ideal that diversity reflects resilience, the environment and education for sustainable development landscape in Africa might be said to be healthy and proliferating. But read against the pressure to produce tangible evidence of change on an African landscape of persistent climate variation and poverty, along with a widening gap between rich and poor, the picture remains challenging. These contrasting readings are notable at a time when we are looking towards the Association for the Development of Education in Africa (ADEA) Triennial in February, 2012, the Rio+20 Earth Summit in June 2012 and our own EEASA +30 conference in September 2012. The UN Decade of Education for Sustainable Development is characterised by a proliferation of education imperatives. These emerged as modern education in response to the issues of the day and now a modernity in deepening crisis.
- Full Text:
- Authors: O'Donoghue, Rob B
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/387134 , vital:68209 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122240"
- Description: This journal reflects a diversity of environment and sustainability education research and viewpoints alongside two synthesis papers. Read as a whole and within a widely held ideal that diversity reflects resilience, the environment and education for sustainable development landscape in Africa might be said to be healthy and proliferating. But read against the pressure to produce tangible evidence of change on an African landscape of persistent climate variation and poverty, along with a widening gap between rich and poor, the picture remains challenging. These contrasting readings are notable at a time when we are looking towards the Association for the Development of Education in Africa (ADEA) Triennial in February, 2012, the Rio+20 Earth Summit in June 2012 and our own EEASA +30 conference in September 2012. The UN Decade of Education for Sustainable Development is characterised by a proliferation of education imperatives. These emerged as modern education in response to the issues of the day and now a modernity in deepening crisis.
- Full Text:
A series of systematic case studies on the treatment of rape-related PTSD in the South African context implications for practice and policy
- Authors: Padmanabhanunni, Anita
- Date: 2011
- Subjects: Post-traumatic stress disorder -- South Africa -- Treatment Post-traumatic stress disorder -- Patients Case studies Rape victims -- Counseling of -- South Africa Psychic trauma -- Treatment Rape victims -- Counseling of Case studies Cognitive therapy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3035 , http://hdl.handle.net/10962/d1002544
- Description: In 2009, South African police statistics revealed that more than 68 332 women were raped in the country. The evidence from independent researchers has shown that SAPS statistics are highly susceptible to under-reporting and the actual figure is more than double this amount. One pervasive feature of the phenomenology of rape is post-traumatic stress disorder (PTSD). PTSD is a highly debilitating condition with severe individual and societal costs. The condition takes a critical toll on occupational functioning, schooling and personal relationships and is associated with depression, suicide risk, self-harming behaviours and alcohol-abuse problems. The Ehlers and Clark (2000) cognitive model represents the most efficacious treatment for PTSD but the approach is severely under-utilised by South African practitioners working with sexual trauma. The reasons for such under-utilisation relate to a lack of exposure and training surrounding the model and concerns about the transportability of the treatment to a multi-cultural context. One method of addressing these barriers to treatment delivery is through systematic case-based research. Systematic case-based research offers a complementary means of refining theory and developing evidence-based practice in the context of a developing country. The method offers an intensive analysis and description of the particular phenomena under study within its real-life context. It allows the researcher to intensively examine and identify the specific aspects of the therapist’s responses and client’s reactions that contributed to significant change. Unlike efficacy studies, generalisability in case-study research is based on replication on a case-by-case basis and the creation of case law. This research study uses a systematic-case study approach to investigate the applicability of the Ehlers and Clark (2000) model in the treatment of rape-related PTSD in South Africa. The study aims to demonstrate the transportability of the model and develop a needed evidence base for service providers in the country. Seven women participated in the project and lent their treatment process to the research. The participants varied in terms of age, race, culture, socio-economic status and the nature of their sexual trauma. Through synoptic thematic analysis of their therapy process specific client-related personal aspects, client-related contextual factors and state-level factors were found to impede treatment delivery and implementation. The implications of these aspects for clinical practice and social policy are comprehensively discussed.
- Full Text:
- Authors: Padmanabhanunni, Anita
- Date: 2011
- Subjects: Post-traumatic stress disorder -- South Africa -- Treatment Post-traumatic stress disorder -- Patients Case studies Rape victims -- Counseling of -- South Africa Psychic trauma -- Treatment Rape victims -- Counseling of Case studies Cognitive therapy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3035 , http://hdl.handle.net/10962/d1002544
- Description: In 2009, South African police statistics revealed that more than 68 332 women were raped in the country. The evidence from independent researchers has shown that SAPS statistics are highly susceptible to under-reporting and the actual figure is more than double this amount. One pervasive feature of the phenomenology of rape is post-traumatic stress disorder (PTSD). PTSD is a highly debilitating condition with severe individual and societal costs. The condition takes a critical toll on occupational functioning, schooling and personal relationships and is associated with depression, suicide risk, self-harming behaviours and alcohol-abuse problems. The Ehlers and Clark (2000) cognitive model represents the most efficacious treatment for PTSD but the approach is severely under-utilised by South African practitioners working with sexual trauma. The reasons for such under-utilisation relate to a lack of exposure and training surrounding the model and concerns about the transportability of the treatment to a multi-cultural context. One method of addressing these barriers to treatment delivery is through systematic case-based research. Systematic case-based research offers a complementary means of refining theory and developing evidence-based practice in the context of a developing country. The method offers an intensive analysis and description of the particular phenomena under study within its real-life context. It allows the researcher to intensively examine and identify the specific aspects of the therapist’s responses and client’s reactions that contributed to significant change. Unlike efficacy studies, generalisability in case-study research is based on replication on a case-by-case basis and the creation of case law. This research study uses a systematic-case study approach to investigate the applicability of the Ehlers and Clark (2000) model in the treatment of rape-related PTSD in South Africa. The study aims to demonstrate the transportability of the model and develop a needed evidence base for service providers in the country. Seven women participated in the project and lent their treatment process to the research. The participants varied in terms of age, race, culture, socio-economic status and the nature of their sexual trauma. Through synoptic thematic analysis of their therapy process specific client-related personal aspects, client-related contextual factors and state-level factors were found to impede treatment delivery and implementation. The implications of these aspects for clinical practice and social policy are comprehensively discussed.
- Full Text:
A short composition portfolio
- Buitendag, Kingsley Alexander
- Authors: Buitendag, Kingsley Alexander
- Date: 2011
- Subjects: Music -- South Africa Composition (Music)
- Language: English
- Type: text , Thesis , Masters , MMus
- Identifier: vital:2632 , http://hdl.handle.net/10962/d1002297
- Full Text:
- Authors: Buitendag, Kingsley Alexander
- Date: 2011
- Subjects: Music -- South Africa Composition (Music)
- Language: English
- Type: text , Thesis , Masters , MMus
- Identifier: vital:2632 , http://hdl.handle.net/10962/d1002297
- Full Text:
A South African response to ethics in legal education
- Authors: Kruuse, Helen
- Date: 2011
- Language: English
- Type: Article , text
- Identifier: http://hdl.handle.net/10962/54174 , vital:26399 , https://www.routledge.com/The-Ethics-Project-in-Legal-Education/Robertson-Corbin-Tranter-Bartlett/p/book/9780415546515
- Description: The contributions in this volume suggest that "the ethics project in legal education" is increasingly an international one. Even though the strength of commitment by both the profession and the legal academy to "ethics learning" within law schools varies, two fundamental questions confront all who work in this area. First, what is it that we want our students to learn (or, perhaps, in what manner do we want our students to develop) from the teaching of "legal ethics"? Second, how can we create a learning environment that will encourage the nature and quality of learning we think is important?.
- Full Text: false
- Authors: Kruuse, Helen
- Date: 2011
- Language: English
- Type: Article , text
- Identifier: http://hdl.handle.net/10962/54174 , vital:26399 , https://www.routledge.com/The-Ethics-Project-in-Legal-Education/Robertson-Corbin-Tranter-Bartlett/p/book/9780415546515
- Description: The contributions in this volume suggest that "the ethics project in legal education" is increasingly an international one. Even though the strength of commitment by both the profession and the legal academy to "ethics learning" within law schools varies, two fundamental questions confront all who work in this area. First, what is it that we want our students to learn (or, perhaps, in what manner do we want our students to develop) from the teaching of "legal ethics"? Second, how can we create a learning environment that will encourage the nature and quality of learning we think is important?.
- Full Text: false
A stable isotope approach for the early detection and identification of N loading in aquatic ecosystems
- Hill, Jaclyn M, Kaehler, Sven, Hill, Martin P, Coetzee, Julie A
- Authors: Hill, Jaclyn M , Kaehler, Sven , Hill, Martin P , Coetzee, Julie A
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444491 , vital:74245 , https://www.wrc.org.za/wp-content/uploads/mdocs/KV 280.pdf
- Description: Global increases in urbanization and anthropogenic activity within wa-tersheds and catchment areas have resulted in excessive nitrogen loads in aquatic ecosystems. South Africa is deeply dependent on nat-ural resources for its economic health and as a consequence is particu-larly vulnerable to the degradation of its natural capital. Increased nitro-gen loading can result in widespread aquatic ecosystem degradation including: harmful algal blooms, increased turbidity, hypoxia, loss of aquatic vegetation and habitat and fish kills, it is also one of the mecha-nisms driving aquatic weed invasions. Understanding the fate and pro-cessing of anthropogenic nutrients in natural systems is therefore criti-cal for both preserving the well-being and biotic heritage for future gen-erations as well as providing a tremendous opportunity to improve the management driven by science. The objectives of this study were to evaluate the feasibility of mapping anthropogenic pollution through sta-ble isotopes signatures of aquatic plants, to investigate the potential for identifying different pollution sources, concentrations and distributions in a freshwater environment and to determine the utility of these tech-niques in indentifying early eutrophication.
- Full Text:
- Authors: Hill, Jaclyn M , Kaehler, Sven , Hill, Martin P , Coetzee, Julie A
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444491 , vital:74245 , https://www.wrc.org.za/wp-content/uploads/mdocs/KV 280.pdf
- Description: Global increases in urbanization and anthropogenic activity within wa-tersheds and catchment areas have resulted in excessive nitrogen loads in aquatic ecosystems. South Africa is deeply dependent on nat-ural resources for its economic health and as a consequence is particu-larly vulnerable to the degradation of its natural capital. Increased nitro-gen loading can result in widespread aquatic ecosystem degradation including: harmful algal blooms, increased turbidity, hypoxia, loss of aquatic vegetation and habitat and fish kills, it is also one of the mecha-nisms driving aquatic weed invasions. Understanding the fate and pro-cessing of anthropogenic nutrients in natural systems is therefore criti-cal for both preserving the well-being and biotic heritage for future gen-erations as well as providing a tremendous opportunity to improve the management driven by science. The objectives of this study were to evaluate the feasibility of mapping anthropogenic pollution through sta-ble isotopes signatures of aquatic plants, to investigate the potential for identifying different pollution sources, concentrations and distributions in a freshwater environment and to determine the utility of these tech-niques in indentifying early eutrophication.
- Full Text:
A strange counterpoint : classical music performance and identities in Grahamstown, South Africa
- Marais, Terence Wilmot Eugene
- Authors: Marais, Terence Wilmot Eugene
- Date: 2011
- Subjects: Music -- Western influences Music -- Performance -- Psychological aspects Music appreciation -- South Africa -- Grahamstown Music -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2677 , http://hdl.handle.net/10962/d1007491
- Description: This study investigates the perceptions of South African practitioners of Western European Art Music (WEAM), specifically as they relate to the value of WEAM in contemporary South African society. In exploring some of the connections between musical identity and national identity, it sets out to discover what value WEAM holds for a certain group of student pianists. Qualitative empirical data was collected in the form of in-depth, semi-structured interviews and questionnaire responses, and the findings point to numerous, nuanced expressions of self and varied intersections of the nation with musical identity in the life of the individual. Further, WEAM appears to represent a crucial point of identification for these individuals, in each case generating positive affirmations of the self.
- Full Text:
- Authors: Marais, Terence Wilmot Eugene
- Date: 2011
- Subjects: Music -- Western influences Music -- Performance -- Psychological aspects Music appreciation -- South Africa -- Grahamstown Music -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2677 , http://hdl.handle.net/10962/d1007491
- Description: This study investigates the perceptions of South African practitioners of Western European Art Music (WEAM), specifically as they relate to the value of WEAM in contemporary South African society. In exploring some of the connections between musical identity and national identity, it sets out to discover what value WEAM holds for a certain group of student pianists. Qualitative empirical data was collected in the form of in-depth, semi-structured interviews and questionnaire responses, and the findings point to numerous, nuanced expressions of self and varied intersections of the nation with musical identity in the life of the individual. Further, WEAM appears to represent a crucial point of identification for these individuals, in each case generating positive affirmations of the self.
- Full Text:
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:
- 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:
A white man in exile
- Authors: Krueger, Anton
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/229459 , vital:49677 , xlink:href="https://doi.org/10.1080/10137548.2011.636974"
- Description: This article explores intersections between understandings of masculinity and nationalism. Etymologically, ‘patriotism’ refers to a love for a fatherland and a patriarchal order; it includes notions of loyalty, honour and a range of qualities often associated with conceptions of masculinity. But if gender remains fixed to these normative constructions, what happens to one’s sense of masculine identity when the national state changes? My interest lies in exploring how white South African men have been repositioned in terms of a shift in their gendered identification, with a reflection on the possibly tragic consequences of maintaining an overly rigid gender role identification. As long as masculinity is embedded within nationalism, it will be caught up within a defensive reactive mode which can turn self-destructive. In order to explore these ideas the article employs as its central metaphor the character of Dawid Olivier, who is the protagonist of Athol Fugard’s Sorrows and Rejoicings (2002).
- Full Text:
- Authors: Krueger, Anton
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/229459 , vital:49677 , xlink:href="https://doi.org/10.1080/10137548.2011.636974"
- Description: This article explores intersections between understandings of masculinity and nationalism. Etymologically, ‘patriotism’ refers to a love for a fatherland and a patriarchal order; it includes notions of loyalty, honour and a range of qualities often associated with conceptions of masculinity. But if gender remains fixed to these normative constructions, what happens to one’s sense of masculine identity when the national state changes? My interest lies in exploring how white South African men have been repositioned in terms of a shift in their gendered identification, with a reflection on the possibly tragic consequences of maintaining an overly rigid gender role identification. As long as masculinity is embedded within nationalism, it will be caught up within a defensive reactive mode which can turn self-destructive. In order to explore these ideas the article employs as its central metaphor the character of Dawid Olivier, who is the protagonist of Athol Fugard’s Sorrows and Rejoicings (2002).
- Full Text: