A cytotoxic pentadecapeptide from a South African Didemnid tunicate
- Gallegos, D, Serrill, J, Parker-Nance, Shirley, Dorrington, Rosemary A, Ishmael, J, McPhail, Kerry L
- Authors: Gallegos, D , Serrill, J , Parker-Nance, Shirley , Dorrington, Rosemary A , Ishmael, J , McPhail, Kerry L
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/65935 , vital:28863 , https://doi.org/10.1055/s-0036-1596683
- Description: publisher version , The rate of discovery of new natural product chemical entities has plateaued, and unique populations of endemic, biologically diverse sessile marine organisms represent increasingly critical opportunities to discover new chemistry. Discovery of the mandelalides [1] as potent inhibitors of cancer cell growth from the new South African tunicate Lissoclinum mandelai is an example of the diverse suites of metabolites with potent biological activities that have been isolated from tunicates and other filter-feeding sessile marine organisms that house complex microbial consortia. Further investigation of archived and new tunicate collections from Algoa Bay, South Africa, has revealed a group of didemnid tunicates with an unusual gelatinous morphology similar to Lissoclinum mandelai. Using a bioassay-guided isolation approach, a new “gelatinous” species of the genus Didemnum has yielded a cytotoxic pentadecapeptide with a molecular mass of 1603.7688 Da, comprising fifteen residues including both proteinogenic and non-proteinogenic amino acids. The pure compound inhibited both HeLa cervical cancer and NCI-H460 non-small cell lung cancer cell lines when tested at 30 nM in preliminary assays against cells seeded at low densities. Inhibition of cancer cells at low starting density may be indicative of an anti-proliferative mechanism of action. The compound did not show antibacterial activity against Vibrio cholera. Didemnin B and its clinically approved analogue dehydrodidemnin B (plitidepsin, Aplidin®) [2, 3] are important macrocyclic depsipeptides from a didemnid tunicate. The pentadecapeptide reported here provides justification for our continued investigation of unique, endemic didemnid tunicates from South Africa as a source of new macrocyclic natural products with cytotoxic, anti-viral or antimicrobial activity. , We acknowledge the South African government for permission to collect the subject tunicate (Collection Permit No. 278 RES2013/43)
- Full Text: false
- Authors: Gallegos, D , Serrill, J , Parker-Nance, Shirley , Dorrington, Rosemary A , Ishmael, J , McPhail, Kerry L
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/65935 , vital:28863 , https://doi.org/10.1055/s-0036-1596683
- Description: publisher version , The rate of discovery of new natural product chemical entities has plateaued, and unique populations of endemic, biologically diverse sessile marine organisms represent increasingly critical opportunities to discover new chemistry. Discovery of the mandelalides [1] as potent inhibitors of cancer cell growth from the new South African tunicate Lissoclinum mandelai is an example of the diverse suites of metabolites with potent biological activities that have been isolated from tunicates and other filter-feeding sessile marine organisms that house complex microbial consortia. Further investigation of archived and new tunicate collections from Algoa Bay, South Africa, has revealed a group of didemnid tunicates with an unusual gelatinous morphology similar to Lissoclinum mandelai. Using a bioassay-guided isolation approach, a new “gelatinous” species of the genus Didemnum has yielded a cytotoxic pentadecapeptide with a molecular mass of 1603.7688 Da, comprising fifteen residues including both proteinogenic and non-proteinogenic amino acids. The pure compound inhibited both HeLa cervical cancer and NCI-H460 non-small cell lung cancer cell lines when tested at 30 nM in preliminary assays against cells seeded at low densities. Inhibition of cancer cells at low starting density may be indicative of an anti-proliferative mechanism of action. The compound did not show antibacterial activity against Vibrio cholera. Didemnin B and its clinically approved analogue dehydrodidemnin B (plitidepsin, Aplidin®) [2, 3] are important macrocyclic depsipeptides from a didemnid tunicate. The pentadecapeptide reported here provides justification for our continued investigation of unique, endemic didemnid tunicates from South Africa as a source of new macrocyclic natural products with cytotoxic, anti-viral or antimicrobial activity. , We acknowledge the South African government for permission to collect the subject tunicate (Collection Permit No. 278 RES2013/43)
- Full Text: false
A discussion of the concept, “place of effective management” and the proposed changes, in the context of South African tax law
- Authors: Singh, Nishika
- Date: 2016
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/4166 , vital:20629
- Description: The concept, “place of effective management”, is used in South African tax legislation to determine the residency of companies and it is also used by the Organisation for Economic Co-operation and Development (OECD) and in many tax treaties as a tie-breaker clause to determine the residency of companies that may appear to be dual resident or to determine which country has the taxing rights to income that may be subject to double tax due to the income being from a source outside of the company’s country of residence. The concept is not defined in any tax legislation and there is no uniform interpretation of the concept globally. The former guidance provided by the South African Revenue Services (SARS) adopted a hierarchal approach and the focus was the implementation of the Board of Directors’ decisions. This interpretation was not aligned to the guidance of the OECD whose focus is the place where the key management and commercial decisions of the entity are made. The current SARS guidance has been aligned to the OECD guidance and, essentially, the core principle is to determine who makes the key commercial and management decisions of the company and the place where these individuals are making these decisions. The current SARS and OECD guidance have now been aligned. The current SARS and OECD interpretations have been found to be a more effective tie-breaker clause than the former interpretations.
- Full Text:
- Authors: Singh, Nishika
- Date: 2016
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/4166 , vital:20629
- Description: The concept, “place of effective management”, is used in South African tax legislation to determine the residency of companies and it is also used by the Organisation for Economic Co-operation and Development (OECD) and in many tax treaties as a tie-breaker clause to determine the residency of companies that may appear to be dual resident or to determine which country has the taxing rights to income that may be subject to double tax due to the income being from a source outside of the company’s country of residence. The concept is not defined in any tax legislation and there is no uniform interpretation of the concept globally. The former guidance provided by the South African Revenue Services (SARS) adopted a hierarchal approach and the focus was the implementation of the Board of Directors’ decisions. This interpretation was not aligned to the guidance of the OECD whose focus is the place where the key management and commercial decisions of the entity are made. The current SARS guidance has been aligned to the OECD guidance and, essentially, the core principle is to determine who makes the key commercial and management decisions of the company and the place where these individuals are making these decisions. The current SARS and OECD guidance have now been aligned. The current SARS and OECD interpretations have been found to be a more effective tie-breaker clause than the former interpretations.
- Full Text:
A dynamically weighted multi-modal biometric security system
- Brown, Dane L, Bradshaw, Karen L
- Authors: Brown, Dane L , Bradshaw, Karen L
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/476629 , vital:77945 , ISBN 9780620724180
- Description: The face, fingerprint and palmprint feature vectors are automatically extracted and dynamically selected for fusion at the feature-level, toward an improved human identification accuracy. The feature-level has a higher potential accuracy than the match score-level. However, leveraging this potential requires a new approach. This work demonstrates a novel dynamic weighting algorithm for improved image-based biometric feature-fusion. A comparison is performed on uni-modal, bi-modal, tri-modal and proposed dynamic approaches. The proposed dynamic approach yields a high genuine acceptance rate of 99.25% genuine acceptance rate at a false acceptance rate of 1% on challenging datasets and big impostor datasets.
- Full Text:
- Authors: Brown, Dane L , Bradshaw, Karen L
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/476629 , vital:77945 , ISBN 9780620724180
- Description: The face, fingerprint and palmprint feature vectors are automatically extracted and dynamically selected for fusion at the feature-level, toward an improved human identification accuracy. The feature-level has a higher potential accuracy than the match score-level. However, leveraging this potential requires a new approach. This work demonstrates a novel dynamic weighting algorithm for improved image-based biometric feature-fusion. A comparison is performed on uni-modal, bi-modal, tri-modal and proposed dynamic approaches. The proposed dynamic approach yields a high genuine acceptance rate of 99.25% genuine acceptance rate at a false acceptance rate of 1% on challenging datasets and big impostor datasets.
- Full Text:
A dynamically weighted multi-modal biometric security system
- Brown, Dane L, Bradshaw, Karen L
- Authors: Brown, Dane L , Bradshaw, Karen L
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/473684 , vital:77672 , xlink:href="https://www.researchgate.net/publication/315839228_A_Dynamically_Weighted_Multi-Modal_Biometric_Security_System"
- Description: The face, fingerprint and palmprint feature vectors are automatically extracted and dynamically selected for fusion at the feature-level, toward an improved human identification accuracy. The feature-level has a higher potential accuracy than the match score-level. However, leveraging this potential requires a new approach. This work demonstrates a novel dynamic weighting algorithm for improved image-based biometric feature-fusion. A comparison is performed on uni-modal, bi-modal, tri-modal and proposed dynamic approaches. The proposed dynamic approach yields a high genuine acceptance rate of 99.25% genuine acceptance rate at a false acceptance rate of 1% on challenging datasets and big impostor datasets.
- Full Text:
- Authors: Brown, Dane L , Bradshaw, Karen L
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/473684 , vital:77672 , xlink:href="https://www.researchgate.net/publication/315839228_A_Dynamically_Weighted_Multi-Modal_Biometric_Security_System"
- Description: The face, fingerprint and palmprint feature vectors are automatically extracted and dynamically selected for fusion at the feature-level, toward an improved human identification accuracy. The feature-level has a higher potential accuracy than the match score-level. However, leveraging this potential requires a new approach. This work demonstrates a novel dynamic weighting algorithm for improved image-based biometric feature-fusion. A comparison is performed on uni-modal, bi-modal, tri-modal and proposed dynamic approaches. The proposed dynamic approach yields a high genuine acceptance rate of 99.25% genuine acceptance rate at a false acceptance rate of 1% on challenging datasets and big impostor datasets.
- Full Text:
A feminist perspective on autonomism and commoning, with reference to Zimbabwe
- Alexander, Tarryn, Helliker, Kirk D
- Authors: Alexander, Tarryn , Helliker, Kirk D
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71374 , vital:29838 , https://doi.org/10.1080/02589001.2016.1235353
- Description: This article engages with the autonomist Marxism of John Holloway from a feminist standpoint. The positions developed by this feminist critique are used to shed new light on the land occupations in contemporary Zimbabwe. Though sympathetic to his work, we argue that Holloway does not sufficiently address gender identity with specific reference to social reproduction and women. The notions of the commons and the process of commoning are consistent with Holloway’s autonomist framework and its complementarities to Silvia Federici’s Marxist feminist lens on the commons is highlighted. Against a tendency within autonomist and commoning theories, we argue for a pronounced identitarian politics as grounded in localised struggles undertaken by women as women. We privilege the significance of women asserting and revaluing their identities as part of a possible project of transformation. For us, struggling against and beyond what exists is invariably rooted in struggles within what exists (including identities).
- Full Text: false
- Authors: Alexander, Tarryn , Helliker, Kirk D
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71374 , vital:29838 , https://doi.org/10.1080/02589001.2016.1235353
- Description: This article engages with the autonomist Marxism of John Holloway from a feminist standpoint. The positions developed by this feminist critique are used to shed new light on the land occupations in contemporary Zimbabwe. Though sympathetic to his work, we argue that Holloway does not sufficiently address gender identity with specific reference to social reproduction and women. The notions of the commons and the process of commoning are consistent with Holloway’s autonomist framework and its complementarities to Silvia Federici’s Marxist feminist lens on the commons is highlighted. Against a tendency within autonomist and commoning theories, we argue for a pronounced identitarian politics as grounded in localised struggles undertaken by women as women. We privilege the significance of women asserting and revaluing their identities as part of a possible project of transformation. For us, struggling against and beyond what exists is invariably rooted in struggles within what exists (including identities).
- Full Text: false
A Foucauldian analysis of discourses shaping perspectives, responses, and experiences on the accessibility, availability and distribution of condoms in some school communities in Kavango Region
- Authors: Ngalangi, Naftal Sakaria
- Date: 2016
- Subjects: Foucault, Michel, 1926-1984 -- Methodology , Condom use -- Namibia , Sex instruction for teenagers -- Namibia , HIV infections -- Prevention -- Namibia , AIDS (Disease) -- Prevention -- Namibia , Education, Secondary -- Namibia , Teenage pregnancy -- Namibia , Sexual abstinence -- Moral and ethical aspects
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2061 , http://hdl.handle.net/10962/d1019990
- Description: Condom use is promoted as an effective method for prevention and contraception for people who practice or are at risk of practicing high-risk sexual behaviors. According to the UNAIDS (2009) report, condoms are the only resource available to prevent the sexual spread of the HI-Virus; and with regard to family planning, the same report proposes that condoms expand the choices, have no medical side effects, and thus provide dual protection against pregnancy and disease. However, in Africa as elsewhere in the world, condom use has been fiercely debated. The debates on the accessibility, availability and distribution of condoms in schools are not new nor are they uncontested. In Namibia, the HIV and AIDS policy in education does not explain how, when and by whom condoms should be made available to learners. This leaves it to schools to decide on how (and whether) to make condoms available to learners. As a result, individual school‘s choices not only vary, but are mediated by different factors that are not always in the best interest of learners who, as the foregoing discussion suggests, continue to participate in behaviour that, amongst other things, puts them at risk of HIV infection and falling pregnant. Relying on Foucault‘s theory of discourses, this study investigated the dominant discourses that shape learner, teacher, parent religious and traditional leader and traditional healer perspectives, responses, and experiences with regard to the accessibility, availability, and distribution of condoms in school. The study was conducted in nine schools in Kavango Region in Namibia using a mixed methods approach. The study used triangulation in the data collection process through the use of questionnaires where 792 learners participated in this component, and focus group discussions and individual interviews targeting four groups namely, learners, teachers, parents and religious leaders, traditional leaders and traditional healers. The quantitative data were analyzed using the Statistical Packages for Social Sciences (SPSS), and findings from the focus group discussions and individual interviews were analyzed identifying themes and patterns and then organizing them into coherent categories with sub-categories. The study revealed that the majority of adult participants opposed the idea of making condoms available in schools; advocating abstinence instead. This was despite evidence on the prevalence of sexual activity amongst youth in the community. Reasons had to do with various competing and hierarchized discourses operating to shape participant beliefs, perspectives, and responses in a highly regulated and surveilled social and cultural context. Put differently, the dominant discourses invoked a particular sexual subject; authorized and legitimated who invoked such a subject; who was and was not allowed to speak on sexual matters; as well as how sexual matters were brought into the public space of schools. Such authorization and legitimation regulated the discursive space in which discussions on sexual health, safe sex, and resources such as condoms were permitted; with negative consequences for the sexual well-being of youth in Kavango Region. The study also highlighted the tension between freedom, choice, and rights, showing how complex in fact is decision to make condoms available in school. On the one hand, teenagers positioned themselves as capable subjects who had the right to exercise choice over their sexual lives. Requesting parent consent was thus viewed as a violation of this right to choose. Such a position displayed authority and agency by learners that was pitted against views amongst adults in this study that positioned youth as having no agency. In their view, youth (a) were still children and thus innocent and pure, (b) ought to abstain, and (c) were difficult to control given the modern context. Adults believed that early sexual involvement by learners did not result from lack of vigilance and control on their part, but rather from exposure to modern social mores. The study concluded that (a) schools remain difficult spaces not only for mediating discussions of sex and sexuality, but also for providing resources to mitigate sexual risk amongst leaners, (b) in highly regulated societies, dominant religious discourses are produced and reproduced in and through existing institutions such as family, church, and schools; highlighting how these serve to normalize beliefs and perspectives, (c) the dominant discourses shaping communities in which schools find themselves remain inconsistent with school discourses that are shaped by modernist conceptions of childhood and youth, and (b) adult choices to sanction and obstruct schools from making condoms available (and in the case of teachers, not accessible and distributable) put the very children at risk that they propose to be protecting.
- Full Text:
- Authors: Ngalangi, Naftal Sakaria
- Date: 2016
- Subjects: Foucault, Michel, 1926-1984 -- Methodology , Condom use -- Namibia , Sex instruction for teenagers -- Namibia , HIV infections -- Prevention -- Namibia , AIDS (Disease) -- Prevention -- Namibia , Education, Secondary -- Namibia , Teenage pregnancy -- Namibia , Sexual abstinence -- Moral and ethical aspects
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2061 , http://hdl.handle.net/10962/d1019990
- Description: Condom use is promoted as an effective method for prevention and contraception for people who practice or are at risk of practicing high-risk sexual behaviors. According to the UNAIDS (2009) report, condoms are the only resource available to prevent the sexual spread of the HI-Virus; and with regard to family planning, the same report proposes that condoms expand the choices, have no medical side effects, and thus provide dual protection against pregnancy and disease. However, in Africa as elsewhere in the world, condom use has been fiercely debated. The debates on the accessibility, availability and distribution of condoms in schools are not new nor are they uncontested. In Namibia, the HIV and AIDS policy in education does not explain how, when and by whom condoms should be made available to learners. This leaves it to schools to decide on how (and whether) to make condoms available to learners. As a result, individual school‘s choices not only vary, but are mediated by different factors that are not always in the best interest of learners who, as the foregoing discussion suggests, continue to participate in behaviour that, amongst other things, puts them at risk of HIV infection and falling pregnant. Relying on Foucault‘s theory of discourses, this study investigated the dominant discourses that shape learner, teacher, parent religious and traditional leader and traditional healer perspectives, responses, and experiences with regard to the accessibility, availability, and distribution of condoms in school. The study was conducted in nine schools in Kavango Region in Namibia using a mixed methods approach. The study used triangulation in the data collection process through the use of questionnaires where 792 learners participated in this component, and focus group discussions and individual interviews targeting four groups namely, learners, teachers, parents and religious leaders, traditional leaders and traditional healers. The quantitative data were analyzed using the Statistical Packages for Social Sciences (SPSS), and findings from the focus group discussions and individual interviews were analyzed identifying themes and patterns and then organizing them into coherent categories with sub-categories. The study revealed that the majority of adult participants opposed the idea of making condoms available in schools; advocating abstinence instead. This was despite evidence on the prevalence of sexual activity amongst youth in the community. Reasons had to do with various competing and hierarchized discourses operating to shape participant beliefs, perspectives, and responses in a highly regulated and surveilled social and cultural context. Put differently, the dominant discourses invoked a particular sexual subject; authorized and legitimated who invoked such a subject; who was and was not allowed to speak on sexual matters; as well as how sexual matters were brought into the public space of schools. Such authorization and legitimation regulated the discursive space in which discussions on sexual health, safe sex, and resources such as condoms were permitted; with negative consequences for the sexual well-being of youth in Kavango Region. The study also highlighted the tension between freedom, choice, and rights, showing how complex in fact is decision to make condoms available in school. On the one hand, teenagers positioned themselves as capable subjects who had the right to exercise choice over their sexual lives. Requesting parent consent was thus viewed as a violation of this right to choose. Such a position displayed authority and agency by learners that was pitted against views amongst adults in this study that positioned youth as having no agency. In their view, youth (a) were still children and thus innocent and pure, (b) ought to abstain, and (c) were difficult to control given the modern context. Adults believed that early sexual involvement by learners did not result from lack of vigilance and control on their part, but rather from exposure to modern social mores. The study concluded that (a) schools remain difficult spaces not only for mediating discussions of sex and sexuality, but also for providing resources to mitigate sexual risk amongst leaners, (b) in highly regulated societies, dominant religious discourses are produced and reproduced in and through existing institutions such as family, church, and schools; highlighting how these serve to normalize beliefs and perspectives, (c) the dominant discourses shaping communities in which schools find themselves remain inconsistent with school discourses that are shaped by modernist conceptions of childhood and youth, and (b) adult choices to sanction and obstruct schools from making condoms available (and in the case of teachers, not accessible and distributable) put the very children at risk that they propose to be protecting.
- Full Text:
A Geopolitics of knowledge and the value of discomfort:
- Authors: Simbao, Ruth K
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/146444 , vital:38526 , https://www.ru.ac.za/fineart/latestnews/alutacontinuadoingitfordaddytenyearson.html
- Description: In 2006, the short essay ‘Doing it for Daddy’ by visual artist Sharlene Khan caused controversy when it expressed the opinion that since 1994, ‘transformation’ in the visual arts field in South Africa seemed to have halted at the point of White women replacing White men in positions of power. It questioned this new position of dominance in institutions that remained colonially and racially untransformed. On the 16 and 17th of September 2016, the School of Fine Art at Rhodes University will host a one-day symposium ‘A luta Continua: Doing it for Daddy - Ten years on…’ which seeks to both commemorate that article and those who ‘speak up’, but also, fundamentally, to continue looking at the ways in which various social oppressions intersect in the fields of art history and visual arts in South Africa. Presenters include Khwezi Gule, Nontobeko Ntombela, Nomusa Makhubu, Same Mdluli, Fouad Asfour, Ruth Simbao, Sharlene Khan, students from Wits School of Arts and Rhodes Art History and Visual Culture, as well as a performance by visual artist Sikhumbuzo Makandula.
- Full Text:
- Authors: Simbao, Ruth K
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/146444 , vital:38526 , https://www.ru.ac.za/fineart/latestnews/alutacontinuadoingitfordaddytenyearson.html
- Description: In 2006, the short essay ‘Doing it for Daddy’ by visual artist Sharlene Khan caused controversy when it expressed the opinion that since 1994, ‘transformation’ in the visual arts field in South Africa seemed to have halted at the point of White women replacing White men in positions of power. It questioned this new position of dominance in institutions that remained colonially and racially untransformed. On the 16 and 17th of September 2016, the School of Fine Art at Rhodes University will host a one-day symposium ‘A luta Continua: Doing it for Daddy - Ten years on…’ which seeks to both commemorate that article and those who ‘speak up’, but also, fundamentally, to continue looking at the ways in which various social oppressions intersect in the fields of art history and visual arts in South Africa. Presenters include Khwezi Gule, Nontobeko Ntombela, Nomusa Makhubu, Same Mdluli, Fouad Asfour, Ruth Simbao, Sharlene Khan, students from Wits School of Arts and Rhodes Art History and Visual Culture, as well as a performance by visual artist Sikhumbuzo Makandula.
- Full Text:
A longitudinal study of DNS traffic: understanding current DNS practice and abuse
- Authors: Van Zyl, Ignus
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3707 , vital:20537
- Description: This thesis examines a dataset spanning 21 months, containing 3,5 billion DNS packets. Traffic on TCP and UDP port 53, was captured on a production /24 IP block. The purpose of this thesis is twofold. The first is to create an understanding of current practice and behavior within the DNS infrastructure, the second to explore current threats faced by the DNS and the various systems that implement it. This is achieved by drawing on analysis and observations from the captured data. Aspects of the operation of DNS on the greater Internet are considered in this research with reference to the observed trends in the dataset, A thorough analysis of current DNS TTL implementation is made with respect to all response traffic, as well as sections looking at observed DNS TTL values for ,za domain replies and NX DOMAIN flagged replies. This thesis found that TTL values implemented are much lower than has been recommended in previous years, and that the TTL decrease is prevalent in most, but not all EE TTL implementation. With respect to the nature of DNS operations, this thesis also concerns itself with an analysis of the geoloeation of authoritative servers for local (,za) domains, and offers further observations towards the latency generated by the choice of authoritative server location for a given ,za domain. It was found that the majority of ,za domain authoritative servers are international, which results in latency generation that is multiple times greater than observed latencies for local authoritative servers. Further analysis is done with respect to NX DOM AIN behavior captured across the dataset. These findings outlined the cost of DNS miseonfiguration as well as highlighting instances of NXDOMAIN generation through malicious practice. With respect to DNS abuses, original research with respect to long-term scanning generated as a result of amplification attack activity on the greater Internet is presented. Many instances of amplification domain scans were captured during the packet capture, and an attempt is made to correlate that activity temporally with known amplification attack reports. The final area that this thesis deals with is the relatively new field of Bitflipping and Bitsquatting, delivering results on bitflip detection and evaluation over the course of the entire dataset. The detection methodology is outlined, and the final results are compared to findings given in recent bitflip literature.
- Full Text:
- Authors: Van Zyl, Ignus
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3707 , vital:20537
- Description: This thesis examines a dataset spanning 21 months, containing 3,5 billion DNS packets. Traffic on TCP and UDP port 53, was captured on a production /24 IP block. The purpose of this thesis is twofold. The first is to create an understanding of current practice and behavior within the DNS infrastructure, the second to explore current threats faced by the DNS and the various systems that implement it. This is achieved by drawing on analysis and observations from the captured data. Aspects of the operation of DNS on the greater Internet are considered in this research with reference to the observed trends in the dataset, A thorough analysis of current DNS TTL implementation is made with respect to all response traffic, as well as sections looking at observed DNS TTL values for ,za domain replies and NX DOMAIN flagged replies. This thesis found that TTL values implemented are much lower than has been recommended in previous years, and that the TTL decrease is prevalent in most, but not all EE TTL implementation. With respect to the nature of DNS operations, this thesis also concerns itself with an analysis of the geoloeation of authoritative servers for local (,za) domains, and offers further observations towards the latency generated by the choice of authoritative server location for a given ,za domain. It was found that the majority of ,za domain authoritative servers are international, which results in latency generation that is multiple times greater than observed latencies for local authoritative servers. Further analysis is done with respect to NX DOM AIN behavior captured across the dataset. These findings outlined the cost of DNS miseonfiguration as well as highlighting instances of NXDOMAIN generation through malicious practice. With respect to DNS abuses, original research with respect to long-term scanning generated as a result of amplification attack activity on the greater Internet is presented. Many instances of amplification domain scans were captured during the packet capture, and an attempt is made to correlate that activity temporally with known amplification attack reports. The final area that this thesis deals with is the relatively new field of Bitflipping and Bitsquatting, delivering results on bitflip detection and evaluation over the course of the entire dataset. The detection methodology is outlined, and the final results are compared to findings given in recent bitflip literature.
- Full Text:
A morphogenic and laminated system explanation of position-practice systems and professional development training in mainstreaming education for sustainable development in African universities
- Authors: Agbedahin, Adesuwa Vanessa
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/584 , vital:19972
- Description: This research focuses on Education for Sustainable Development (ESD) in Higher Education Institutions (HEIs), particularly in Africa. It explores the roles and practices of these institutions, especially their professionals, in the Anthropocene era where increasing concern for contemporary environmental and sustainability issues and risks emerge. The study presents a longitudinal case study of institutions and participants of the Swedish/African/Asian International Training Programme (ITP) on ESD in Higher Education (HE), who are mostly university educators. This thesis however focuses on African ITP participants only. At a macro level, the research sought to examine how African university educators have contributed to the United Nations Decade of Education for Sustainable Development (UNDESD) through their participation in the ITP (which is a change oriented professional development training programme on ESD) and the associated ESD ‘change projects’. The change projects are ITP participants’ direct attempts to mainstream environment and sustainability issues, concerns, and concepts into core university functions and practices: teaching, research, community engagement, and management operations and policy engagement. At a meso level the study sought insight into how educators in national institutions were supported by sub-regional and regional initiatives, institutions and organisations, including the Mainstreaming of Environment and Sustainability in African (MESA) Universities Partnership programme, especially an initiative supported by the Southern African Development Community Regional Environmental Education Programme to provide (limited) seed funding to three southern African universities to establish what are known as ‘MESA Chairs’, with dedicated time and support for MESA activities in their universities . At a micro level, this research sought to investigate how the position-practice systems and the ITP shape (enable or constrain) effective ESD mainstreaming in higher education, and how the morphogenetic approach and laminated system can be used to understand and explain these dynamics and their relations with meso and macro level engagements. The research sought to understand these dynamics through empirical investigations using survey questionnaires, interviews, document analysis and field visits. The research is constituted as theoretical, conceptual, methodological and analytical exploration using a singular and nested case study research approach, underlaboured by a critical realist ontology, and drawing on a social learning epistemology and social realist morphogenetic interpretive lens. In particular, ontological depth was sought via critical realist laminated system explanation. See Chapter Two for details. This study was carried out in three phases. Phase one encapsulates the investigation of all ITP ESD in higher education alumni who were Asian and African participants from the inception of the ITP to its completion, over a six-year period (2008-2013). This included 280 academics from Asia and Africa in 35 countries in Asia and Africa from 106 institutions in Asia and Africa with their 139 change projects. The outcome of phase one of the research is only included in this thesis as an appendix (see Appendix 3; Agbedahin & Lotz-Sisitka, 2015). However, this phase provided and formed the foundational data that was expanded in phases two and three for the purpose of this study. Phase two of this research concentrated on a less broad population of research participants comprising only all African ITP alumni, from all regions in Africa. The overall data collection and analysis included 162 academics in 23 African countries from 66 institutions with their 81 change projects. The aim was to investigate and provide a morphogenetic explanation of their change projects and how the relationship between participants’ positions and practices (and that of others) may influence ESD mainstreaming in universities. The outcome of this phase two investigation is presented in Chapter Four. In phase three, (nested) case studies of Swaziland, Zambia, and Botswana (in the southern Africa region), which included all the ESD ITP HE participants therein and the three corresponding EE/ESD MESA Chairs, were developed. The population sample in this phase three therefore contained 20 academics, from six institutions with their nine change projects. This phase was characterised by field trips to these countries and in-depth data collection and analysis in order to investigate and deepen the morphogenetic explanations of their change projects and how the relationship between participants’ positions and practices (and that of others) have indeed influenced the ESD mainstreaming in universities. The outcome of this phase three research is presented in Chapters Five, Six and Seven. The final Chapter Eight of this thesis focuses on the seven scalar laminated system perspective and reflections on this research and discussion of these perspectives for supporting the mainstreaming of ESD in African higher education institutions and more specifically in the three case countries and respective institutions presented in Chapters Five, Six, and Seven. The seven scalar laminated system is presented in relation to the position-practice system, and draws on morphogenetic social realist and social learning theory to provide perspective on the actual change processes. Chapter Eight also includes a discussion on social learning and its implication for ESD mainstreaming, and provides recommendations for further research. The outcome of the theoretical exploration underpinning this study provided a potential model for understanding ESD learning and change processes that are facilitated by professional development training programmes in the context of ESD in HE. This study also provides a model for appraising educational changes in time and in space, especially in relation to ESD, or the types of changes that can be brought about by professional development interventions such as those provided by the ITP and how they can be tracked, monitored and documented. For the field of professional or academic development in higher education, this research highlights the significance of the relationship between position-practice systems, professional development interventions and institutional transformation. For the field of ESD in higher education, this study shows the need for in-depth consideration of the position-practice system and sphere of influence of change agents and related stakeholders in and around their institutions in the design and development of professional development programmes. It further sheds light on the laminated system of factors that contextually constrain and/or enable effective ESD mainstreaming at individual, collective, institutional, national, regional and global levels.
- Full Text:
- Authors: Agbedahin, Adesuwa Vanessa
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/584 , vital:19972
- Description: This research focuses on Education for Sustainable Development (ESD) in Higher Education Institutions (HEIs), particularly in Africa. It explores the roles and practices of these institutions, especially their professionals, in the Anthropocene era where increasing concern for contemporary environmental and sustainability issues and risks emerge. The study presents a longitudinal case study of institutions and participants of the Swedish/African/Asian International Training Programme (ITP) on ESD in Higher Education (HE), who are mostly university educators. This thesis however focuses on African ITP participants only. At a macro level, the research sought to examine how African university educators have contributed to the United Nations Decade of Education for Sustainable Development (UNDESD) through their participation in the ITP (which is a change oriented professional development training programme on ESD) and the associated ESD ‘change projects’. The change projects are ITP participants’ direct attempts to mainstream environment and sustainability issues, concerns, and concepts into core university functions and practices: teaching, research, community engagement, and management operations and policy engagement. At a meso level the study sought insight into how educators in national institutions were supported by sub-regional and regional initiatives, institutions and organisations, including the Mainstreaming of Environment and Sustainability in African (MESA) Universities Partnership programme, especially an initiative supported by the Southern African Development Community Regional Environmental Education Programme to provide (limited) seed funding to three southern African universities to establish what are known as ‘MESA Chairs’, with dedicated time and support for MESA activities in their universities . At a micro level, this research sought to investigate how the position-practice systems and the ITP shape (enable or constrain) effective ESD mainstreaming in higher education, and how the morphogenetic approach and laminated system can be used to understand and explain these dynamics and their relations with meso and macro level engagements. The research sought to understand these dynamics through empirical investigations using survey questionnaires, interviews, document analysis and field visits. The research is constituted as theoretical, conceptual, methodological and analytical exploration using a singular and nested case study research approach, underlaboured by a critical realist ontology, and drawing on a social learning epistemology and social realist morphogenetic interpretive lens. In particular, ontological depth was sought via critical realist laminated system explanation. See Chapter Two for details. This study was carried out in three phases. Phase one encapsulates the investigation of all ITP ESD in higher education alumni who were Asian and African participants from the inception of the ITP to its completion, over a six-year period (2008-2013). This included 280 academics from Asia and Africa in 35 countries in Asia and Africa from 106 institutions in Asia and Africa with their 139 change projects. The outcome of phase one of the research is only included in this thesis as an appendix (see Appendix 3; Agbedahin & Lotz-Sisitka, 2015). However, this phase provided and formed the foundational data that was expanded in phases two and three for the purpose of this study. Phase two of this research concentrated on a less broad population of research participants comprising only all African ITP alumni, from all regions in Africa. The overall data collection and analysis included 162 academics in 23 African countries from 66 institutions with their 81 change projects. The aim was to investigate and provide a morphogenetic explanation of their change projects and how the relationship between participants’ positions and practices (and that of others) may influence ESD mainstreaming in universities. The outcome of this phase two investigation is presented in Chapter Four. In phase three, (nested) case studies of Swaziland, Zambia, and Botswana (in the southern Africa region), which included all the ESD ITP HE participants therein and the three corresponding EE/ESD MESA Chairs, were developed. The population sample in this phase three therefore contained 20 academics, from six institutions with their nine change projects. This phase was characterised by field trips to these countries and in-depth data collection and analysis in order to investigate and deepen the morphogenetic explanations of their change projects and how the relationship between participants’ positions and practices (and that of others) have indeed influenced the ESD mainstreaming in universities. The outcome of this phase three research is presented in Chapters Five, Six and Seven. The final Chapter Eight of this thesis focuses on the seven scalar laminated system perspective and reflections on this research and discussion of these perspectives for supporting the mainstreaming of ESD in African higher education institutions and more specifically in the three case countries and respective institutions presented in Chapters Five, Six, and Seven. The seven scalar laminated system is presented in relation to the position-practice system, and draws on morphogenetic social realist and social learning theory to provide perspective on the actual change processes. Chapter Eight also includes a discussion on social learning and its implication for ESD mainstreaming, and provides recommendations for further research. The outcome of the theoretical exploration underpinning this study provided a potential model for understanding ESD learning and change processes that are facilitated by professional development training programmes in the context of ESD in HE. This study also provides a model for appraising educational changes in time and in space, especially in relation to ESD, or the types of changes that can be brought about by professional development interventions such as those provided by the ITP and how they can be tracked, monitored and documented. For the field of professional or academic development in higher education, this research highlights the significance of the relationship between position-practice systems, professional development interventions and institutional transformation. For the field of ESD in higher education, this study shows the need for in-depth consideration of the position-practice system and sphere of influence of change agents and related stakeholders in and around their institutions in the design and development of professional development programmes. It further sheds light on the laminated system of factors that contextually constrain and/or enable effective ESD mainstreaming at individual, collective, institutional, national, regional and global levels.
- Full Text:
A multi-biometric feature-fusion framework for improved uni-modal and multi-modal human identification
- Brown, Dane L, Bradshaw, Karen L
- Authors: Brown, Dane L , Bradshaw, Karen L
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/473696 , vital:77673 , xlink:href="https://ieeexplore.ieee.org/abstract/document/7568927"
- Description: The lack of multi-biometric fusion guidelines at the feature-level are addressed in this work. A feature-fusion framework is geared toward improving human identification accuracy for both single and multiple biometrics. The foundation of the framework is the improvement over a state-of-the-art uni-modal biometric verification system, which is extended into a multi-modal identification system. A novel multi-biometric system is thus designed based on the framework, which serves as fusion guidelines for multi-biometric applications that fuse at the feature-level. This framework was applied to the face and fingerprint to achieve a 91.11% recognition accuracy when using only a single training sample. Furthermore, an accuracy of 99.69% was achieved when using five training samples.
- Full Text:
- Authors: Brown, Dane L , Bradshaw, Karen L
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/473696 , vital:77673 , xlink:href="https://ieeexplore.ieee.org/abstract/document/7568927"
- Description: The lack of multi-biometric fusion guidelines at the feature-level are addressed in this work. A feature-fusion framework is geared toward improving human identification accuracy for both single and multiple biometrics. The foundation of the framework is the improvement over a state-of-the-art uni-modal biometric verification system, which is extended into a multi-modal identification system. A novel multi-biometric system is thus designed based on the framework, which serves as fusion guidelines for multi-biometric applications that fuse at the feature-level. This framework was applied to the face and fingerprint to achieve a 91.11% recognition accuracy when using only a single training sample. Furthermore, an accuracy of 99.69% was achieved when using five training samples.
- Full Text:
A multi-threading approach to secure VERIFYPIN
- Frieslaar, Ibraheem, Irwin, Barry V W
- Authors: Frieslaar, Ibraheem , Irwin, Barry V W
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429244 , vital:72570 , https://ieeexplore.ieee.org/abstract/document/7802952
- Description: This research investigates the use of a multi-threaded framework as a software countermeasure mechanism to prevent attacks on the verifypin process in a pin-acceptance program. The implementation comprises of using various mathematical operations along side a pin-acceptance program in a multi-threaded environment. These threads are inserted randomly on each execution of the program to create confusion for the attacker. Moreover, the research proposes a more improved version of the pin-acceptance program by segmenting the pro-gram. The conventional approach is to check each character one at a time. This research takes the verifying process and separates each character check into its individual thread. Furthermore, the order of each verified thread is randomised. This further assists in the obfuscation of the process where the system checks for a correct character. Finally, the research demonstrates it is able to be more secure than the conventional countermeasures of random time delays and insertion of dummy code.
- Full Text:
- Authors: Frieslaar, Ibraheem , Irwin, Barry V W
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429244 , vital:72570 , https://ieeexplore.ieee.org/abstract/document/7802952
- Description: This research investigates the use of a multi-threaded framework as a software countermeasure mechanism to prevent attacks on the verifypin process in a pin-acceptance program. The implementation comprises of using various mathematical operations along side a pin-acceptance program in a multi-threaded environment. These threads are inserted randomly on each execution of the program to create confusion for the attacker. Moreover, the research proposes a more improved version of the pin-acceptance program by segmenting the pro-gram. The conventional approach is to check each character one at a time. This research takes the verifying process and separates each character check into its individual thread. Furthermore, the order of each verified thread is randomised. This further assists in the obfuscation of the process where the system checks for a correct character. Finally, the research demonstrates it is able to be more secure than the conventional countermeasures of random time delays and insertion of dummy code.
- Full Text:
A narrative-discursive analysis of abortion decision-making in Zimbabwe
- Authors: Chiweshe, Malvern Tatenda
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/496 , vital:19964
- Description: Most research on abortion decision-making has looked at the factors or influences that are seen to affect abortion decision-making and thus take a health determinants approach. However, this approach is rarely able to account for the complex, multi-faceted nature of abortion decision-making, and it is often not located within a framework that can unpick the complex array of power relations that underpins the process of abortion decision-making. Research on abortion decision-making has rarely examined how women who undergo a termination of pregnancy (TOP) construct micro-narratives of the decision to terminate the pregnancy and also how these women are positioned by the service providers who interact with them. Using a Foucauldian postcolonial feminist approach and narrative-discursive analysis, this study explores abortion decision-making narratives in a Zimbabwean context where abortion laws are restrictive. In this study I elicited the narratives of women who had undergone an abortion about how they came to make the decision and proceeded to terminate the pregnancy. I highlight the discourses employed in constructing these narratives and how women position themselves in these narratives and discourses. These are then compared to the subject positions enabled in health service providers’ narratives on the same topic. These narratives are then linked to the social discourses and power relations that work to enable or constrain reproductive justice. The data were collected from three sites in Harare, Zimbabwe. The three sites were Harare Hospital, Epworth and Mufakose. An adapted version of Wengraf’s (2001) narrative interview was used to elicit narratives from 18 women who had terminated pregnancies (six at each site). Semi-structured interviews were conducted with six service providers (two nurses at Harare Hospital, two village health workers in Epworth and two nurses in Mufakose). All the service providers interviewed have experience working with women who have terminated pregnancies. In narrating their stories about their abortions, the women employed discursive resources around shame, stigma, religion, health and culture. These discursive resources were drawn upon in the construction of the women’s micro-narratives. The women spoke in a socially sanctioned manner where stories were enabled and constrained by particular religious, cultural and gendered discursive resources. In these stories, cultural constructions, gendered understandings of motherhood and femininity constrained reproductive justice for women who have terminated pregnancies. Comparisons of the way women positioned themselves and how they were positioned by health service providers point to the existence of social discourses and power relations that work to constrain reproductive justice. While the women saw themselves as having ‘unsupportable pregnancies’, the service providers positioned them as being evil, selfish and irresponsible. The negative positions deployed by the service providers point to the vilification and blaming of women who have undergone a termination of pregnancy. In these positions, the woman is at fault and there is silence on the role of men in abortion decision-making. In the women’s narratives and the health service providers positioning of the women a ‘reproductive rights’ discourse was absent. This was significant as much of the activism around abortion has centred on the woman’s rights to her body. Where rights were mentioned, it was in reference to foetal rights (using cultural, moralistic religious understandings of abortion as killing). The missing ‘reproductive rights’ discourse points to a need to move from a reproductive rights framework to a reproductive justice framework that can be applied through local understandings of hunhu/ubuntu. By doing this, abortion is not seen as a ‘choice’ that a woman makes but rather as involving broader social and environmental circumstances that make a pregnancy ‘unsupportable’.
- Full Text:
- Authors: Chiweshe, Malvern Tatenda
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/496 , vital:19964
- Description: Most research on abortion decision-making has looked at the factors or influences that are seen to affect abortion decision-making and thus take a health determinants approach. However, this approach is rarely able to account for the complex, multi-faceted nature of abortion decision-making, and it is often not located within a framework that can unpick the complex array of power relations that underpins the process of abortion decision-making. Research on abortion decision-making has rarely examined how women who undergo a termination of pregnancy (TOP) construct micro-narratives of the decision to terminate the pregnancy and also how these women are positioned by the service providers who interact with them. Using a Foucauldian postcolonial feminist approach and narrative-discursive analysis, this study explores abortion decision-making narratives in a Zimbabwean context where abortion laws are restrictive. In this study I elicited the narratives of women who had undergone an abortion about how they came to make the decision and proceeded to terminate the pregnancy. I highlight the discourses employed in constructing these narratives and how women position themselves in these narratives and discourses. These are then compared to the subject positions enabled in health service providers’ narratives on the same topic. These narratives are then linked to the social discourses and power relations that work to enable or constrain reproductive justice. The data were collected from three sites in Harare, Zimbabwe. The three sites were Harare Hospital, Epworth and Mufakose. An adapted version of Wengraf’s (2001) narrative interview was used to elicit narratives from 18 women who had terminated pregnancies (six at each site). Semi-structured interviews were conducted with six service providers (two nurses at Harare Hospital, two village health workers in Epworth and two nurses in Mufakose). All the service providers interviewed have experience working with women who have terminated pregnancies. In narrating their stories about their abortions, the women employed discursive resources around shame, stigma, religion, health and culture. These discursive resources were drawn upon in the construction of the women’s micro-narratives. The women spoke in a socially sanctioned manner where stories were enabled and constrained by particular religious, cultural and gendered discursive resources. In these stories, cultural constructions, gendered understandings of motherhood and femininity constrained reproductive justice for women who have terminated pregnancies. Comparisons of the way women positioned themselves and how they were positioned by health service providers point to the existence of social discourses and power relations that work to constrain reproductive justice. While the women saw themselves as having ‘unsupportable pregnancies’, the service providers positioned them as being evil, selfish and irresponsible. The negative positions deployed by the service providers point to the vilification and blaming of women who have undergone a termination of pregnancy. In these positions, the woman is at fault and there is silence on the role of men in abortion decision-making. In the women’s narratives and the health service providers positioning of the women a ‘reproductive rights’ discourse was absent. This was significant as much of the activism around abortion has centred on the woman’s rights to her body. Where rights were mentioned, it was in reference to foetal rights (using cultural, moralistic religious understandings of abortion as killing). The missing ‘reproductive rights’ discourse points to a need to move from a reproductive rights framework to a reproductive justice framework that can be applied through local understandings of hunhu/ubuntu. By doing this, abortion is not seen as a ‘choice’ that a woman makes but rather as involving broader social and environmental circumstances that make a pregnancy ‘unsupportable’.
- Full Text:
A passive auxiliary circuit with interphase transformer applied in 12-pulse converters to provide clean power utility interface
- Shih, Der-Chun, Young, Chung-Ming, Whiteley, Chris G
- Authors: Shih, Der-Chun , Young, Chung-Ming , Whiteley, Chris G
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67095 , vital:29031 , https://doi.org/10.1080/02533839.2016.1230029
- Description: publisher version , This paper proposes a passive auxiliary circuit which can be added to an interphase transformer (PAC + IPT) configuration to reduce the total harmonic distortion (THD) existing in 12-pulse diode rectifier converter systems at AC mains. The proposed PAC + IPT compensation method is a simple structure, with low power consumption and requires no extra DC power supply. We present the theoretical analysis of the proposed topology that lessens the total harmonic distortion (THD) and evaluate the dynamic simulation results on a 12-pulse converter system and a 3-kW laboratory prototype. Both the simulation and the experimental results show that the proposed PAC + IPT compensation method can improve the power quality and provide a clean power utility interface of AC line input currents for a conventional 12-pulse diode rectifier converter.
- Full Text: false
- Authors: Shih, Der-Chun , Young, Chung-Ming , Whiteley, Chris G
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67095 , vital:29031 , https://doi.org/10.1080/02533839.2016.1230029
- Description: publisher version , This paper proposes a passive auxiliary circuit which can be added to an interphase transformer (PAC + IPT) configuration to reduce the total harmonic distortion (THD) existing in 12-pulse diode rectifier converter systems at AC mains. The proposed PAC + IPT compensation method is a simple structure, with low power consumption and requires no extra DC power supply. We present the theoretical analysis of the proposed topology that lessens the total harmonic distortion (THD) and evaluate the dynamic simulation results on a 12-pulse converter system and a 3-kW laboratory prototype. Both the simulation and the experimental results show that the proposed PAC + IPT compensation method can improve the power quality and provide a clean power utility interface of AC line input currents for a conventional 12-pulse diode rectifier converter.
- Full Text: false
A psychobiographical study of Charlize Theron
- Authors: Prenter, Tracey
- Date: 2016
- Subjects: Theron, Charlize -- Psychology , Motion picture actors and actresses -- South Africa -- Biography , Motion picture actors and actresses -- United States -- Biography , Psychology -- Biographical methods
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3272 , http://hdl.handle.net/10962/d1020843
- Description: Psychobiographers study the lives of extraordinary, prominent, and enigmatic individuals. Psychobiographical research advances our insight into the uniqueness and complexity of the human personality and therefore makes a substantial contribution towards one of the major objectives of the field of psychology. Purposive sampling was employed to select Charlize Theron as the subject of this psychobiographical study. As the only South African who has won an Oscar, Theron is an exceptional individual who demonstrates tenacity and a will to succeed despite significant traumatic events in her childhood. The case study data was organised and analysed according to the general analytic approach developed by Huberman and Miles (2002) and one of Alexander’s (1990) strategies, namely questioning the data. Erikson’s psychosocial theory (1950, 1963, 1995) was selected to guide this study because it recognises the impact of socio-cultural influences on developmental processes and provides a comprehensive, staged framework for studying Theron’s personality development. This study contributes to the development of psychobiographical research in South Africa.
- Full Text:
- Authors: Prenter, Tracey
- Date: 2016
- Subjects: Theron, Charlize -- Psychology , Motion picture actors and actresses -- South Africa -- Biography , Motion picture actors and actresses -- United States -- Biography , Psychology -- Biographical methods
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3272 , http://hdl.handle.net/10962/d1020843
- Description: Psychobiographers study the lives of extraordinary, prominent, and enigmatic individuals. Psychobiographical research advances our insight into the uniqueness and complexity of the human personality and therefore makes a substantial contribution towards one of the major objectives of the field of psychology. Purposive sampling was employed to select Charlize Theron as the subject of this psychobiographical study. As the only South African who has won an Oscar, Theron is an exceptional individual who demonstrates tenacity and a will to succeed despite significant traumatic events in her childhood. The case study data was organised and analysed according to the general analytic approach developed by Huberman and Miles (2002) and one of Alexander’s (1990) strategies, namely questioning the data. Erikson’s psychosocial theory (1950, 1963, 1995) was selected to guide this study because it recognises the impact of socio-cultural influences on developmental processes and provides a comprehensive, staged framework for studying Theron’s personality development. This study contributes to the development of psychobiographical research in South Africa.
- Full Text:
A review of generalized linear models for count data with emphasis on current geospatial procedures
- Authors: Michell, Justin Walter
- Date: 2016
- Subjects: Spatial analysis (Statistics) , Bayesian statistical decision theory , Geospatial data , Malaria -- Botswana -- Statistics , Malaria -- Botswana -- Research -- Statistical methods
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:5582 , http://hdl.handle.net/10962/d1019989
- Description: Analytical problems caused by over-fitting, confounding and non-independence in the data is a major challenge for variable selection. As more variables are tested against a certain data set, there is a greater risk that some will explain the data merely by chance, but will fail to explain new data. The main aim of this study is to employ a systematic and practicable variable selection process for the spatial analysis and mapping of historical malaria risk in Botswana using data collected from the MARA (Mapping Malaria Risk in Africa) project and environmental and climatic datasets from various sources. Details of how a spatial database is compiled for a statistical analysis to proceed is provided. The automation of the entire process is also explored. The final bayesian spatial model derived from the non-spatial variable selection procedure using Markov Chain Monte Carlo simulation was fitted to the data. Winter temperature had the greatest effect of malaria prevalence in Botswana. Summer rainfall, maximum temperature of the warmest month, annual range of temperature, altitude and distance to closest water source were also significantly associated with malaria prevalence in the final spatial model after accounting for spatial correlation. Using this spatial model malaria prevalence at unobserved locations was predicted, producing a smooth risk map covering Botswana. The automation of both compiling the spatial database and the variable selection procedure proved challenging and could only be achieved in parts of the process. The non-spatial selection procedure proved practical and was able to identify stable explanatory variables and provide an objective means for selecting one variable over another, however ultimately it was not entirely successful due to the fact that a unique set of spatial variables could not be selected.
- Full Text:
- Authors: Michell, Justin Walter
- Date: 2016
- Subjects: Spatial analysis (Statistics) , Bayesian statistical decision theory , Geospatial data , Malaria -- Botswana -- Statistics , Malaria -- Botswana -- Research -- Statistical methods
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:5582 , http://hdl.handle.net/10962/d1019989
- Description: Analytical problems caused by over-fitting, confounding and non-independence in the data is a major challenge for variable selection. As more variables are tested against a certain data set, there is a greater risk that some will explain the data merely by chance, but will fail to explain new data. The main aim of this study is to employ a systematic and practicable variable selection process for the spatial analysis and mapping of historical malaria risk in Botswana using data collected from the MARA (Mapping Malaria Risk in Africa) project and environmental and climatic datasets from various sources. Details of how a spatial database is compiled for a statistical analysis to proceed is provided. The automation of the entire process is also explored. The final bayesian spatial model derived from the non-spatial variable selection procedure using Markov Chain Monte Carlo simulation was fitted to the data. Winter temperature had the greatest effect of malaria prevalence in Botswana. Summer rainfall, maximum temperature of the warmest month, annual range of temperature, altitude and distance to closest water source were also significantly associated with malaria prevalence in the final spatial model after accounting for spatial correlation. Using this spatial model malaria prevalence at unobserved locations was predicted, producing a smooth risk map covering Botswana. The automation of both compiling the spatial database and the variable selection procedure proved challenging and could only be achieved in parts of the process. The non-spatial selection procedure proved practical and was able to identify stable explanatory variables and provide an objective means for selecting one variable over another, however ultimately it was not entirely successful due to the fact that a unique set of spatial variables could not be selected.
- Full Text:
A River of Blood Flows: Lerato Shadi’s ‘Noka Ya Bokamoso’
- Authors: Makandula, Sikhumbuzo
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147258 , vital:38609 , https://artthrob.co.za/2016/07/13/a-river-of-blood-flows-lerato-shadis-noka-ya-bokamoso/
- Description: The title of Lerato Shadi’s show, ‘Noka Ya Bokamoso,’ which opened at National Arts Festival in Grahamstown, translates from Setswana to ‘a river of tomorrow.’ In the Albany gallery you encounter Shadi performing Mosako Wa Nako. She sits silently crocheting a ball of red wool into a scroll which unfurls with indecipherable writing. Shadi’s isolation from the rest of the artworks on the exhibition draws you closer, emphasising the rhythmic movement of her hands.
- Full Text:
- Authors: Makandula, Sikhumbuzo
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147258 , vital:38609 , https://artthrob.co.za/2016/07/13/a-river-of-blood-flows-lerato-shadis-noka-ya-bokamoso/
- Description: The title of Lerato Shadi’s show, ‘Noka Ya Bokamoso,’ which opened at National Arts Festival in Grahamstown, translates from Setswana to ‘a river of tomorrow.’ In the Albany gallery you encounter Shadi performing Mosako Wa Nako. She sits silently crocheting a ball of red wool into a scroll which unfurls with indecipherable writing. Shadi’s isolation from the rest of the artworks on the exhibition draws you closer, emphasising the rhythmic movement of her hands.
- Full Text:
A sharing platform for Indicators of Compromise
- Rudman, Lauren, Irwin, Barry V W
- Authors: Rudman, Lauren , Irwin, Barry V W
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427831 , vital:72465 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622961_A_sharing_platform_for_Indicators_of_Compromise/links/5b9a1ad1a6fdcc59bf8dfe51/A-sharing-platform-for-Indicators-of-Compromise.pdf
- Description: In this paper, we will describe the functionality of a proof of concept sharing platform for sharing cyber threat information. Information is shared in the Structured Threat Information eXpression (STIX) language displayed in HTML. We focus on the sharing of network Indicators of Compromise generated by malware samples. Our work is motivated by the need to provide a platform for exchanging comprehensive network level Indicators. Accordingly we demonstrate the functionality of our proof of concept project. We will discuss how to use some functions of the platform, such as sharing STIX Indicators, navigating around and downloading defense mechanisims. It will be shown how threat information can be converted into different formats to allow them to be used in firewall and Intrusion Detection System (IDS) rules. This is an extension to the sharing platform and makes the creation of network level defense mechanisms efficient. Two API functions of the platform will be successfully tested and are useful because this can allow for the bulk sharing and of threat information.
- Full Text:
- Authors: Rudman, Lauren , Irwin, Barry V W
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427831 , vital:72465 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622961_A_sharing_platform_for_Indicators_of_Compromise/links/5b9a1ad1a6fdcc59bf8dfe51/A-sharing-platform-for-Indicators-of-Compromise.pdf
- Description: In this paper, we will describe the functionality of a proof of concept sharing platform for sharing cyber threat information. Information is shared in the Structured Threat Information eXpression (STIX) language displayed in HTML. We focus on the sharing of network Indicators of Compromise generated by malware samples. Our work is motivated by the need to provide a platform for exchanging comprehensive network level Indicators. Accordingly we demonstrate the functionality of our proof of concept project. We will discuss how to use some functions of the platform, such as sharing STIX Indicators, navigating around and downloading defense mechanisims. It will be shown how threat information can be converted into different formats to allow them to be used in firewall and Intrusion Detection System (IDS) rules. This is an extension to the sharing platform and makes the creation of network level defense mechanisms efficient. Two API functions of the platform will be successfully tested and are useful because this can allow for the bulk sharing and of threat information.
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A sociological analysis of the experiences of acceptance of Christian gay men within the Methodist Church of Southern Africa (MCSA) in Grahamstown
- Authors: Sipungu, Thoko Andy
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3961 , vital:20573
- Description: Buffington, Luibhéid, & Guy (2014: 1) argue that “in the contemporary world, our own sexuality and our sense of the sexualities of others colour all aspects of contemporary life, from interpersonal relations to foreign affairs.” In line with this statement, this study provides an account of how a person’s gay sexuality can possibly colour that person’s experience of acceptance by the Methodist Church of Southern Africa (MCSA) in Grahamstown. Samuel Hill (2008: 6) notes that there is an urgent need to create a dialectic between religious and secular discourse with regards to furthering our understanding of sexuality. Thus this thesis seeks to contribute to the body of scholarship that explores and discusses the disjuncture between one’s homosexual identity and one’s religious identity. Barton (2012: 2) notes that “gay people are often talked about but seldom listened to; rarely are they asked about their own oppression and the individuals and institutions oppressing them.” While adopting a qualitative approach utilising interviews to explore the stories of the respondents, this study applies Bourdieu’s concepts of field, habitus, social capital and symbolic violence in order to analyse the experiences of acceptance of gay men within the Methodist Church of Southern Africa (MCSA) in Grahamstown. With regard to the use Bourdieu’s concepts in the analysis of the experiences, the following dimensions were considered: i) construction of a gay identity within the field of Christianity as represented by the MCSA in this context, ii) the impact the field has on the ‘gay habitus’, iii) Social capital as an advantageous strategy in constructing a gay identity within the church, and iv) symbolic violence that gay men experience within the church. In analysing the conditions of the acceptance that gay men receive within the church, this study also uses Jacques Derrida’s concept of hospitality.
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- Authors: Sipungu, Thoko Andy
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3961 , vital:20573
- Description: Buffington, Luibhéid, & Guy (2014: 1) argue that “in the contemporary world, our own sexuality and our sense of the sexualities of others colour all aspects of contemporary life, from interpersonal relations to foreign affairs.” In line with this statement, this study provides an account of how a person’s gay sexuality can possibly colour that person’s experience of acceptance by the Methodist Church of Southern Africa (MCSA) in Grahamstown. Samuel Hill (2008: 6) notes that there is an urgent need to create a dialectic between religious and secular discourse with regards to furthering our understanding of sexuality. Thus this thesis seeks to contribute to the body of scholarship that explores and discusses the disjuncture between one’s homosexual identity and one’s religious identity. Barton (2012: 2) notes that “gay people are often talked about but seldom listened to; rarely are they asked about their own oppression and the individuals and institutions oppressing them.” While adopting a qualitative approach utilising interviews to explore the stories of the respondents, this study applies Bourdieu’s concepts of field, habitus, social capital and symbolic violence in order to analyse the experiences of acceptance of gay men within the Methodist Church of Southern Africa (MCSA) in Grahamstown. With regard to the use Bourdieu’s concepts in the analysis of the experiences, the following dimensions were considered: i) construction of a gay identity within the field of Christianity as represented by the MCSA in this context, ii) the impact the field has on the ‘gay habitus’, iii) Social capital as an advantageous strategy in constructing a gay identity within the church, and iv) symbolic violence that gay men experience within the church. In analysing the conditions of the acceptance that gay men receive within the church, this study also uses Jacques Derrida’s concept of hospitality.
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A study of factors enhancing truck driver retention at Tanker Services, Imperial Logistics, South Africa
- Authors: Goss, Cayley Amy
- Date: 2016
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:868 , http://hdl.handle.net/10962/d1021250
- Description: The aim of this qualitative study was to gain an understanding of the factors that enhance truck driver retention at Tanker Services, Imperial Logistics, South Africa. The specific objectives of the study were to (1) explore factors which influence the retention of truck drivers from the perspectives of immediate supervisors of these drivers at Tanker Services Branches in Durban, Johannesburg, and Cape Town; (2) to identify the means Tanker Services adopts in meeting factors influential to truck driver retention; and (3) to provide recommendations on how to successfully retain truck drivers in this logistics organisation in South Africa. The research methodology of this study involved interviewing ten immediate managers of truck drivers at Tanker Services, Imperial Logistics. Specifically, data was collected through the use of individual, in-depth and semi-structured interviews to investigate the most influential factors affecting truck driver retention. The results of this research outline factors important to the truck drivers at Tanker Services from the perspectives of their immediate supervisors - most of whom were previously truck drivers themselves. The findings of this research identified the general factors that affect Tanker Services Truck drivers as follows: formal and informal rewards, competitive compensation, a work environment of quality equipment, high safety standards and recreational facilities. Furthermore, interpersonal relations and company reputation were found most influential to truck drivers in this South African logistics context.
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- Authors: Goss, Cayley Amy
- Date: 2016
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:868 , http://hdl.handle.net/10962/d1021250
- Description: The aim of this qualitative study was to gain an understanding of the factors that enhance truck driver retention at Tanker Services, Imperial Logistics, South Africa. The specific objectives of the study were to (1) explore factors which influence the retention of truck drivers from the perspectives of immediate supervisors of these drivers at Tanker Services Branches in Durban, Johannesburg, and Cape Town; (2) to identify the means Tanker Services adopts in meeting factors influential to truck driver retention; and (3) to provide recommendations on how to successfully retain truck drivers in this logistics organisation in South Africa. The research methodology of this study involved interviewing ten immediate managers of truck drivers at Tanker Services, Imperial Logistics. Specifically, data was collected through the use of individual, in-depth and semi-structured interviews to investigate the most influential factors affecting truck driver retention. The results of this research outline factors important to the truck drivers at Tanker Services from the perspectives of their immediate supervisors - most of whom were previously truck drivers themselves. The findings of this research identified the general factors that affect Tanker Services Truck drivers as follows: formal and informal rewards, competitive compensation, a work environment of quality equipment, high safety standards and recreational facilities. Furthermore, interpersonal relations and company reputation were found most influential to truck drivers in this South African logistics context.
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A study of the influence of employee empowerment on organizational citizenship behaviours of teachers within Grahamstown independent senior schools
- Authors: Johnston, Dean Allan
- Date: 2016
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:869 , http://hdl.handle.net/10962/d1021314
- Description: This research investigates the influence of empowerment on organisational citizenship behaviours (OCB) of teachers within Independent Senior schools in Grahamstown. Teachers, as a schools driving force, contribute immensely to the education of its students as well as determine the success and effectiveness of the school as an educational institution. The nature of a teacher’s work, and indirectly the principal’s job of managing these teachers, is complex and difficult to define as there are only certain behaviours which can be contractually obliged from teachers. Further behaviours which are beneficial to the organisation, such as OCB, need to be induced via incentives or encouraged via certain behavioural management initiatives, such as increased levels of empowerment. It is important for schools to encourage their teachers to participate in such beneficial behaviours as not all behaviours can be dictated or managed through contractual limitations. Previous studies and literature reviewed suggest that OCB is an important variable that significantly influences a schools performance. Such studies and literature suggest that empowerment could induce greater levels of OCB. The concepts of OCB and empowerment are defined and discussed and a 58 item Questionnaire is formulated based on the two concepts, drawn mainly from Short and Rinehart (1992) and Bogler and Somech (2004). The Questionnaire is divided into two parts, firstly OCB and secondly empowerment. Each section of the Questionnaire is divided into the relevant categories and dimensions as prescribed by past literature. The first part determines the behaviours which the participants believe form part of a teachers ‘in-role’ behaviour, therefore also determines which behaviours the participants believe are ‘extra-role’ or OCB. The second part determines the participant’s perception of their empowerment in their own workplace. This research makes use of an online Questionnaire. The data is collected and described using averages, modes and medians. This data is organised in a manner which further allows for a Pearson correlation analysis test to be run. This test is used to establish the correlation relationship between the two variables in this research and the statistical significance of this relationship is analysed by observing the respective p-value. The conclusion is drawn that there exists four statistically significant positively correlated relationships between the empowerment dimension (decision making, status, self-efficacy and impact) and OCB. However there exists a weak positively correlated non-statistically significant relationship between empowerment and OCB. This suggests that empowerment as a whole does not greatly influence higher levels of OCB, however the four individual dimensions of empowerment do have a positive influence.
- Full Text:
- Authors: Johnston, Dean Allan
- Date: 2016
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:869 , http://hdl.handle.net/10962/d1021314
- Description: This research investigates the influence of empowerment on organisational citizenship behaviours (OCB) of teachers within Independent Senior schools in Grahamstown. Teachers, as a schools driving force, contribute immensely to the education of its students as well as determine the success and effectiveness of the school as an educational institution. The nature of a teacher’s work, and indirectly the principal’s job of managing these teachers, is complex and difficult to define as there are only certain behaviours which can be contractually obliged from teachers. Further behaviours which are beneficial to the organisation, such as OCB, need to be induced via incentives or encouraged via certain behavioural management initiatives, such as increased levels of empowerment. It is important for schools to encourage their teachers to participate in such beneficial behaviours as not all behaviours can be dictated or managed through contractual limitations. Previous studies and literature reviewed suggest that OCB is an important variable that significantly influences a schools performance. Such studies and literature suggest that empowerment could induce greater levels of OCB. The concepts of OCB and empowerment are defined and discussed and a 58 item Questionnaire is formulated based on the two concepts, drawn mainly from Short and Rinehart (1992) and Bogler and Somech (2004). The Questionnaire is divided into two parts, firstly OCB and secondly empowerment. Each section of the Questionnaire is divided into the relevant categories and dimensions as prescribed by past literature. The first part determines the behaviours which the participants believe form part of a teachers ‘in-role’ behaviour, therefore also determines which behaviours the participants believe are ‘extra-role’ or OCB. The second part determines the participant’s perception of their empowerment in their own workplace. This research makes use of an online Questionnaire. The data is collected and described using averages, modes and medians. This data is organised in a manner which further allows for a Pearson correlation analysis test to be run. This test is used to establish the correlation relationship between the two variables in this research and the statistical significance of this relationship is analysed by observing the respective p-value. The conclusion is drawn that there exists four statistically significant positively correlated relationships between the empowerment dimension (decision making, status, self-efficacy and impact) and OCB. However there exists a weak positively correlated non-statistically significant relationship between empowerment and OCB. This suggests that empowerment as a whole does not greatly influence higher levels of OCB, however the four individual dimensions of empowerment do have a positive influence.
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