Exploring the potential of imines as antiprotozoan agents with focus on t. Brucei and p. Falciparum
- Authors: Oluwafemi, Kola Augustus
- Date: 2018
- Subjects: Protozoa , Parasites , Imines , Nuclear magnetic resonance , HeLa cells , Plasmodium falciparum , Trypanosoma brucei , Isomerism
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/62235 , vital:28145 , DOI 10.21504/10962/62235
- Description: This work focuses on the design, synthesis and evaluation of imine-containing heterocyclic and acyclic compounds with special focus on their bioactivity against parasitic protozoans (P. falciparum and T. brucei) - given the context of drug resistance in the treatment of malaria and Human African sleeping sickness and the fact that several bioactive organic compounds have been reported to possess the imino group. Starting from 2-aminopyridine, novel #-alkylated-5-bromo-7-azabenzimidazoles and substituted 5-bromo-1-(carbamoylmethy)-7-azabenzimidazole derivatives were prepared, and their bioactivity against parasitic protozoans was assessed. NMR spectra of the substituted 5- bromo-1-(carbamoylmethy)-7-azabenzimidazole derivatives exhibited rotational isomerism, and a dynamic NMR study was used in the estimation of the rate constants and the free- energies of activation for rotation. The free-energy differences between the two rotamers were determined and the more stable conformations were predicted. Novel 2-phenyl-7-azabenzimidazoles were also synthesised from 2-aminopyridine. A convenient method for the regioselective formylation of 2,3-diaminopyridines into 2-amino- 7-(benzylimino)pyridine analogues of 2-phenyl-7-azabenzimidazole was developed, and some of the resulting imino derivatives were hydrogenated to verify the importance of the imino moiety for bioactivity. The 2-phenyl-7-azabenzimidazoles and the 2-amino-7- (benzylimino)pyridine analogues were screened for their anti-protozoal activity and their cytotoxicity level was determined against the HeLa cell line. In order to validate the importance of the pyridine moiety, novel #-(phenyl)-2- hydroxybenzylimines, #-(benzyl)-2-hydroxybenzylimines and (±)-trans-1,2-bis[2- hydroxybenzylimino]cyclohexanes were also synthesized and screened for activity against the parasitic protozoans and for cytotoxicity against the HeLa cell line. The biological assay results indicated that these compounds are not significantly cytotoxic and a good number of them show potential as lead compounds for the development of new malaria and trypanosomiasis drugs. , Thesis (PhD) -- Faculty of Science, Chemistry, 2018
- Full Text:
- Authors: Oluwafemi, Kola Augustus
- Date: 2018
- Subjects: Protozoa , Parasites , Imines , Nuclear magnetic resonance , HeLa cells , Plasmodium falciparum , Trypanosoma brucei , Isomerism
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/62235 , vital:28145 , DOI 10.21504/10962/62235
- Description: This work focuses on the design, synthesis and evaluation of imine-containing heterocyclic and acyclic compounds with special focus on their bioactivity against parasitic protozoans (P. falciparum and T. brucei) - given the context of drug resistance in the treatment of malaria and Human African sleeping sickness and the fact that several bioactive organic compounds have been reported to possess the imino group. Starting from 2-aminopyridine, novel #-alkylated-5-bromo-7-azabenzimidazoles and substituted 5-bromo-1-(carbamoylmethy)-7-azabenzimidazole derivatives were prepared, and their bioactivity against parasitic protozoans was assessed. NMR spectra of the substituted 5- bromo-1-(carbamoylmethy)-7-azabenzimidazole derivatives exhibited rotational isomerism, and a dynamic NMR study was used in the estimation of the rate constants and the free- energies of activation for rotation. The free-energy differences between the two rotamers were determined and the more stable conformations were predicted. Novel 2-phenyl-7-azabenzimidazoles were also synthesised from 2-aminopyridine. A convenient method for the regioselective formylation of 2,3-diaminopyridines into 2-amino- 7-(benzylimino)pyridine analogues of 2-phenyl-7-azabenzimidazole was developed, and some of the resulting imino derivatives were hydrogenated to verify the importance of the imino moiety for bioactivity. The 2-phenyl-7-azabenzimidazoles and the 2-amino-7- (benzylimino)pyridine analogues were screened for their anti-protozoal activity and their cytotoxicity level was determined against the HeLa cell line. In order to validate the importance of the pyridine moiety, novel #-(phenyl)-2- hydroxybenzylimines, #-(benzyl)-2-hydroxybenzylimines and (±)-trans-1,2-bis[2- hydroxybenzylimino]cyclohexanes were also synthesized and screened for activity against the parasitic protozoans and for cytotoxicity against the HeLa cell line. The biological assay results indicated that these compounds are not significantly cytotoxic and a good number of them show potential as lead compounds for the development of new malaria and trypanosomiasis drugs. , Thesis (PhD) -- Faculty of Science, Chemistry, 2018
- Full Text:
Extended and Continuous Decline in Effective Population Size Results in Low Genomic Diversity in the World’s Rarest Hyena Species, the Brown Hyena
- Westbury, Michael V, Hartmann, Stefanie, Barlow, Axel, Wiesel, Ingrid, Leo, Viyanna, Welch, Rebecca J, Parker, Daniel M, Sicks, Florian, Ludwig, Arne, Dalén, Love, Hofreiter, Michael
- Authors: Westbury, Michael V , Hartmann, Stefanie , Barlow, Axel , Wiesel, Ingrid , Leo, Viyanna , Welch, Rebecca J , Parker, Daniel M , Sicks, Florian , Ludwig, Arne , Dalén, Love , Hofreiter, Michael
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124482 , vital:35616 , https://doi.org/10.1093/molbev/msy037
- Description: Hyenas (family Hyaenidae), as the sister group to cats (family Felidae), represent a deeply diverging branch within the cat-like carnivores (Feliformia). With an estimated population size of < 10,000 individuals worldwide, the brown hyena (Parahyaena brunnea) represents the rarest of the four extant hyena species and has been listed as Near Threatened by the IUCN. Here, we report a high-coverage genome from a captive bred brown hyena and both mitochondrial and low coverage nuclear genomes of 14 wild-caught brown hyena individuals from across southern Africa.We find that brown hyena harbor extremely low genetic diversity on both the mitochondrial and nuclear level, most likely resulting from a continuous and ongoing decline in effective population size that started_1Ma and dramatically accelerated towards the end of the Pleistocene. Despite the strikingly low genetic diversity, we find no evidence of inbreeding within the captive bred individual and reveal phylogeographic structure, suggesting the existence of several potential subpopulations within the species.
- Full Text:
- Authors: Westbury, Michael V , Hartmann, Stefanie , Barlow, Axel , Wiesel, Ingrid , Leo, Viyanna , Welch, Rebecca J , Parker, Daniel M , Sicks, Florian , Ludwig, Arne , Dalén, Love , Hofreiter, Michael
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124482 , vital:35616 , https://doi.org/10.1093/molbev/msy037
- Description: Hyenas (family Hyaenidae), as the sister group to cats (family Felidae), represent a deeply diverging branch within the cat-like carnivores (Feliformia). With an estimated population size of < 10,000 individuals worldwide, the brown hyena (Parahyaena brunnea) represents the rarest of the four extant hyena species and has been listed as Near Threatened by the IUCN. Here, we report a high-coverage genome from a captive bred brown hyena and both mitochondrial and low coverage nuclear genomes of 14 wild-caught brown hyena individuals from across southern Africa.We find that brown hyena harbor extremely low genetic diversity on both the mitochondrial and nuclear level, most likely resulting from a continuous and ongoing decline in effective population size that started_1Ma and dramatically accelerated towards the end of the Pleistocene. Despite the strikingly low genetic diversity, we find no evidence of inbreeding within the captive bred individual and reveal phylogeographic structure, suggesting the existence of several potential subpopulations within the species.
- Full Text:
Extending functionality and knowledge transfer of the Water Quality Systems Assessment Model
- Slaughter, Andrew R, Gwapedza, David, Mantel, Sukhmani K, Hughes, Denis A, Griffin, Neil J
- Authors: Slaughter, Andrew R , Gwapedza, David , Mantel, Sukhmani K , Hughes, Denis A , Griffin, Neil J
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/438115 , vital:73436 , ISBN 978-0-6392-0059-0 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2448_final.pdf
- Description: This report has been generated by the Water Research Commission (WRC) funded project Developing Climate Change Adaptation Measures and Decision-Support System for Selected South African Water Boards (Project No. K5/2018).
- Full Text:
- Authors: Slaughter, Andrew R , Gwapedza, David , Mantel, Sukhmani K , Hughes, Denis A , Griffin, Neil J
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/438115 , vital:73436 , ISBN 978-0-6392-0059-0 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2448_final.pdf
- Description: This report has been generated by the Water Research Commission (WRC) funded project Developing Climate Change Adaptation Measures and Decision-Support System for Selected South African Water Boards (Project No. K5/2018).
- Full Text:
Extending the NFComms framework for bulk data transfers
- Pennefather, Sean, Bradshaw, Karen L, Irwin, Barry V W
- Authors: Pennefather, Sean , Bradshaw, Karen L , Irwin, Barry V W
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430152 , vital:72669 , https://doi.org/10.1145/3278681.3278686
- Description: In this paper we present the design and implementation of an indirect messaging extension for the existing NFComms framework that pro-vides communication between a network flow processor and host CPU. This extension addresses the bulk throughput limitations of the frame-work and is intended to work in conjunction with existing communication mediums. Testing of the framework extensions shows an increase in throughput performance of up to 300× that of the current direct mes-sage passing framework at the cost of increased single message laten-cy of up to 2×. This trade-off is considered acceptable as the proposed extensions are intended for bulk data transfer only while the existing message passing functionality of the framework is preserved and can be used in situations where low latency is required for small messages.
- Full Text:
- Authors: Pennefather, Sean , Bradshaw, Karen L , Irwin, Barry V W
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430152 , vital:72669 , https://doi.org/10.1145/3278681.3278686
- Description: In this paper we present the design and implementation of an indirect messaging extension for the existing NFComms framework that pro-vides communication between a network flow processor and host CPU. This extension addresses the bulk throughput limitations of the frame-work and is intended to work in conjunction with existing communication mediums. Testing of the framework extensions shows an increase in throughput performance of up to 300× that of the current direct mes-sage passing framework at the cost of increased single message laten-cy of up to 2×. This trade-off is considered acceptable as the proposed extensions are intended for bulk data transfer only while the existing message passing functionality of the framework is preserved and can be used in situations where low latency is required for small messages.
- Full Text:
Factors contributing to taxpayer morale: a multi-country perspective
- Authors: Kosiorek, Jakub
- Date: 2018
- Subjects: Taxpayer compliance -- South Africa , Tax evasion -- South Africa , Taxpayer compliance -- Social aspects -- South Africa , Taxpayer compliance -- Economic aspects -- South Africa , Tax morale -- South Africa
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/60255 , vital:27759
- Description: Tax morale is the intrinsic motivation to pay taxes that arises either from a belief that one should contribute towards society by paying taxes or from a moral obligation to pay taxes. The goals of this thesis were to identify the various factors that influence tax morale in a country and use these factors in order to attempt to determine whether tax morale in South Africa has improved or deteriorated over the years. A further goal of this thesis was to identify strategies that could be implemented by a country in order to improve the tax morale of its citizens. The period covered by this thesis is between the years 2000 and 2015. The factors that have an effect on tax morale were identified by a review of the literature. It was found that a number of factors appear to have an impact on tax morale, but certain of these factors are incapable of being directly influenced by tax administrations. With regard to South Africa, it was found that a number of factors affecting tax morale appear to have improved over the years, while others had deteriorated. However, overall it appeared that tax morale in South Africa had deteriorated. With regard to strategies that could be used to improve tax morale, a number were identified by reviewing the literature and include strategies implemented in certain countries, as well as those discussed by scholars. Ii was found that South Africa had implemented a number of the strategies aimed at improving tax morale in its own tax system, but the manner in which some of them were implemented could have been improved. Furthermore, a number of strategies were identified that South Africa has not yet implemented and thus should look to attempting to implement these strategies to improve tax morale.
- Full Text:
- Authors: Kosiorek, Jakub
- Date: 2018
- Subjects: Taxpayer compliance -- South Africa , Tax evasion -- South Africa , Taxpayer compliance -- Social aspects -- South Africa , Taxpayer compliance -- Economic aspects -- South Africa , Tax morale -- South Africa
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/60255 , vital:27759
- Description: Tax morale is the intrinsic motivation to pay taxes that arises either from a belief that one should contribute towards society by paying taxes or from a moral obligation to pay taxes. The goals of this thesis were to identify the various factors that influence tax morale in a country and use these factors in order to attempt to determine whether tax morale in South Africa has improved or deteriorated over the years. A further goal of this thesis was to identify strategies that could be implemented by a country in order to improve the tax morale of its citizens. The period covered by this thesis is between the years 2000 and 2015. The factors that have an effect on tax morale were identified by a review of the literature. It was found that a number of factors appear to have an impact on tax morale, but certain of these factors are incapable of being directly influenced by tax administrations. With regard to South Africa, it was found that a number of factors affecting tax morale appear to have improved over the years, while others had deteriorated. However, overall it appeared that tax morale in South Africa had deteriorated. With regard to strategies that could be used to improve tax morale, a number were identified by reviewing the literature and include strategies implemented in certain countries, as well as those discussed by scholars. Ii was found that South Africa had implemented a number of the strategies aimed at improving tax morale in its own tax system, but the manner in which some of them were implemented could have been improved. Furthermore, a number of strategies were identified that South Africa has not yet implemented and thus should look to attempting to implement these strategies to improve tax morale.
- Full Text:
Factors enabling and constraining research in a small, research-intensive South African University
- Snowball, Jeanette D, Shackleton, Charlie M
- Authors: Snowball, Jeanette D , Shackleton, Charlie M
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/65044 , vital:28659 , http://www.doi: 10.1093/reseval/rvy002
- Description: preprint , Research is increasingly regarded a core facet of university endeavours globally, and research profiles of universities, institutes, and colleges are commonly used as one measure for ranking them. University administrations and funders would be better able to stimulate research if they had insights into context-specific, institutional constraints, and enablers. Yet, there is surprisingly little research on the determinants of research productivity amongst academics employed in the higher education sector, particularly in the global south. Barriers and enablers of research at the individual level may differ, and experience of such may vary across career stage. The objective of the research reported here was to determine what enables and motivates some academics at Rhodes University (South Africa) to do research, what problems and constraints may be making it difficult for those who may wish to do more, and how do these vary in relation to research career stage. An anonymous online survey, with follow-up focus group discussions was used to collect the data. Results show similarities to studies in developed countries, but also reveal disciplinary and career stage differences, which suggest that institutional policies need to take these factors into account when designing support or incentives.
- Full Text:
- Authors: Snowball, Jeanette D , Shackleton, Charlie M
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/65044 , vital:28659 , http://www.doi: 10.1093/reseval/rvy002
- Description: preprint , Research is increasingly regarded a core facet of university endeavours globally, and research profiles of universities, institutes, and colleges are commonly used as one measure for ranking them. University administrations and funders would be better able to stimulate research if they had insights into context-specific, institutional constraints, and enablers. Yet, there is surprisingly little research on the determinants of research productivity amongst academics employed in the higher education sector, particularly in the global south. Barriers and enablers of research at the individual level may differ, and experience of such may vary across career stage. The objective of the research reported here was to determine what enables and motivates some academics at Rhodes University (South Africa) to do research, what problems and constraints may be making it difficult for those who may wish to do more, and how do these vary in relation to research career stage. An anonymous online survey, with follow-up focus group discussions was used to collect the data. Results show similarities to studies in developed countries, but also reveal disciplinary and career stage differences, which suggest that institutional policies need to take these factors into account when designing support or incentives.
- Full Text:
Factors influencing estuarine and coastal connectivity of an estuarine-dependent fishery species, Pomadasys commersonnii (Haemulidae)
- Authors: Dames, Michael Henri
- Date: 2018
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/62307 , vital:28153
- Description: Expected release date-April 2019
- Full Text:
- Authors: Dames, Michael Henri
- Date: 2018
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/62307 , vital:28153
- Description: Expected release date-April 2019
- Full Text:
Factors that shape learner achievement in socially disadvantaged and rural contexts: a social realist study in two rural senior secondary schools in Omusati region, Namibia
- Authors: Shilongo, Erica
- Date: 2018
- Subjects: Academic achievement Namibia Omusati , High school students Namibia Omusati Social conditions , Rural schools Namibia Omusati , Education, Rural Namibia Omusati , Social realism
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62240 , vital:28146
- Description: Learners’ performance and the reasons for either achievement or failure in school has lo ng been a topic of debate. In early research on academic achievement, theorists, educators, biologists and psychologists traditionally focused on the learners from socially disadvantaged family backgrounds who underachieve. Much of the debate internationally centred on whether learner academic achievement / underachievement is a product of hereditary traits or the social context. In particular, arguments for and against whether the reasons for the achievement / underachievement of children from socially disadvantaged families are genetic or the social context in which they find themselves continue unabated. Such explanations do not provide insight into why it is that despite familial (genetic) and social circumstances (social disadvantage), some children succeed and/or are able to act outside expectations of failure. Little research has focused on those in the same or similar contexts who are achieving academic success despite their limiting circumstances and the reasons for their success. This study used a social realist lens to investigate the factors that shape the academic achievement of 12 learners in two rural senior secondary schools in Omusati region, Namibia. All 12 learners are from low socioeconomic family backgrounds. The data was collected through survey, interviews with learners, parents and teachers, field notes and document analysis. The main finding of the study show that contrary to research that portrayed learners’ achievement as determined either by heredity or social contexts, the 12 learners constantly used their agentic possibilities to navigate constraining structural and cultural conditions at regional, familial and school levels to achieve academic success. Their agency was shaped by the socioeconomic conditions in their lives, namely, socioeconomic deprivation; large extended families in rural households, lack of amenities and utilities in their families, participation in household chores, experience of family tragedies and of changes when they were young.
- Full Text:
- Authors: Shilongo, Erica
- Date: 2018
- Subjects: Academic achievement Namibia Omusati , High school students Namibia Omusati Social conditions , Rural schools Namibia Omusati , Education, Rural Namibia Omusati , Social realism
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62240 , vital:28146
- Description: Learners’ performance and the reasons for either achievement or failure in school has lo ng been a topic of debate. In early research on academic achievement, theorists, educators, biologists and psychologists traditionally focused on the learners from socially disadvantaged family backgrounds who underachieve. Much of the debate internationally centred on whether learner academic achievement / underachievement is a product of hereditary traits or the social context. In particular, arguments for and against whether the reasons for the achievement / underachievement of children from socially disadvantaged families are genetic or the social context in which they find themselves continue unabated. Such explanations do not provide insight into why it is that despite familial (genetic) and social circumstances (social disadvantage), some children succeed and/or are able to act outside expectations of failure. Little research has focused on those in the same or similar contexts who are achieving academic success despite their limiting circumstances and the reasons for their success. This study used a social realist lens to investigate the factors that shape the academic achievement of 12 learners in two rural senior secondary schools in Omusati region, Namibia. All 12 learners are from low socioeconomic family backgrounds. The data was collected through survey, interviews with learners, parents and teachers, field notes and document analysis. The main finding of the study show that contrary to research that portrayed learners’ achievement as determined either by heredity or social contexts, the 12 learners constantly used their agentic possibilities to navigate constraining structural and cultural conditions at regional, familial and school levels to achieve academic success. Their agency was shaped by the socioeconomic conditions in their lives, namely, socioeconomic deprivation; large extended families in rural households, lack of amenities and utilities in their families, participation in household chores, experience of family tragedies and of changes when they were young.
- Full Text:
Family functioning and socioeconomic status in South African families: A test of the social causation hypothesis
- Botha, Ferdi, Booysen, Frikkie, Wouters, Edwin
- Authors: Botha, Ferdi , Booysen, Frikkie , Wouters, Edwin
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433176 , vital:72948 , xlink:href="https://doi.org/10.1007/s11205-017-1600-x"
- Description: Optimal family relationships are central to individual well-being. The focus of this paper is on family functioning and how socioeconomic status (SES) explains family functioning. Ecological theory states that a family’s socioeconomic context is determined by macro-systemic factors, thereby influencing individuals’ perceptions of family functioning. Within this context, the social causation hypothesis asserts that social conditions influence family functioning. This paper uses the Family Attachment and Changeability Index as measure of family functioning. SES is viewed as multidimensional and individual-, household-, and subjective SES indices are developed using multiple correspondence analysis. Multivariate regression models suggest that household- and subjective SES are associated with higher levels of perceived flexibility in the family. There is no association between SES and family members’ attachment to each other. In general, the findings support the social causation hypothesis.
- Full Text:
- Authors: Botha, Ferdi , Booysen, Frikkie , Wouters, Edwin
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433176 , vital:72948 , xlink:href="https://doi.org/10.1007/s11205-017-1600-x"
- Description: Optimal family relationships are central to individual well-being. The focus of this paper is on family functioning and how socioeconomic status (SES) explains family functioning. Ecological theory states that a family’s socioeconomic context is determined by macro-systemic factors, thereby influencing individuals’ perceptions of family functioning. Within this context, the social causation hypothesis asserts that social conditions influence family functioning. This paper uses the Family Attachment and Changeability Index as measure of family functioning. SES is viewed as multidimensional and individual-, household-, and subjective SES indices are developed using multiple correspondence analysis. Multivariate regression models suggest that household- and subjective SES are associated with higher levels of perceived flexibility in the family. There is no association between SES and family members’ attachment to each other. In general, the findings support the social causation hypothesis.
- Full Text:
Fatty acids reveal the importance of autochthonous non-vascular plant inputs to an austral river food web
- Moyo, Sydney, Richoux, Nicole B
- Authors: Moyo, Sydney , Richoux, Nicole B
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/456677 , vital:75542 , xlink:href="https://doi.org/10.1007/s10750-017-3347-4"
- Description: We hypothesised that the dominant organic source supporting macroinvertebrate consumers in a South African river is autochthonously produced non-vascular algae (regardless of season), and that the prevalence of autochthony increases with increasing distance from the headwaters. Fatty acid profiles of macroinvertebrates from six sites and four sample times were assessed to characterise the consumer diets and estimate the relative assimilation of autochthonous versus allochthonous-based sources in the food web. Fatty acid markers, ordination analyses and mixing models confirmed that the ultimate nutritional source for the invertebrate assemblages was autochthonous-produced carbon, with some contributions occurring from vascular plants (potentially of allochthonous and autochthonous origin, as some vascular plants were aquatic macrophytes). However, contrary to our second hypothesis, the prevalence of autochthony did not change predictably along the river. Such an autochthonous-based food web is consistent with many large rivers in well-researched regions of the world, although the complexity and variability that we observed in the fatty acid profiles of macroinvertebrate consumers in a small South African river should help stimulate renewed interest in investigations of carbon flow within small rivers from less-studied regions (particularly in arid climates).
- Full Text:
- Authors: Moyo, Sydney , Richoux, Nicole B
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/456677 , vital:75542 , xlink:href="https://doi.org/10.1007/s10750-017-3347-4"
- Description: We hypothesised that the dominant organic source supporting macroinvertebrate consumers in a South African river is autochthonously produced non-vascular algae (regardless of season), and that the prevalence of autochthony increases with increasing distance from the headwaters. Fatty acid profiles of macroinvertebrates from six sites and four sample times were assessed to characterise the consumer diets and estimate the relative assimilation of autochthonous versus allochthonous-based sources in the food web. Fatty acid markers, ordination analyses and mixing models confirmed that the ultimate nutritional source for the invertebrate assemblages was autochthonous-produced carbon, with some contributions occurring from vascular plants (potentially of allochthonous and autochthonous origin, as some vascular plants were aquatic macrophytes). However, contrary to our second hypothesis, the prevalence of autochthony did not change predictably along the river. Such an autochthonous-based food web is consistent with many large rivers in well-researched regions of the world, although the complexity and variability that we observed in the fatty acid profiles of macroinvertebrate consumers in a small South African river should help stimulate renewed interest in investigations of carbon flow within small rivers from less-studied regions (particularly in arid climates).
- Full Text:
Featuring simplicity: jargon and access in contemporary South African art
- Authors: Bereng, Lerato
- Date: 2018
- Language: English
- Type: text , Thesis , Masters , MFA
- Identifier: http://hdl.handle.net/10962/60479 , vital:27784
- Description: The focus of this paper is an exploration of curating and its various forms as understood in a South African art context. In order to understand this context I examine definitions of South African publics as well as different curatorial models. I raise questions around art and accessibility as well as the functions of language as a gate keeper within the visual arts. Through a practical exploration of curatorial methods of engagement, I assess the curator's role as disseminator of information. My final project Conversations at Morija that was held in Morija, Lesotho faces the challenge of curating within a space that has a strong creative platform, but lacks a visual art audience. The exhibition was held during the 2013 Morija Art and Culture festival which is dominated by its music component. Despite Morija being the country's creative centre and sole museum, there is little support for its programme both monetary and in terms of attendance. Through a series of conversations several issues pertaining to Morija, Lesotho and the diaspora were addressed. I look at the absence of creative platforms and alternative curatorial methods that engage the public in a participatory manner. Briefly exploring questions of migrant labour and definitions of what constitutes a diaspora. I look at relatable ways to engage the local audience whilst maintaining a creative core in which to spark dialogue around pertinent matters relating to the country.
- Full Text:
- Authors: Bereng, Lerato
- Date: 2018
- Language: English
- Type: text , Thesis , Masters , MFA
- Identifier: http://hdl.handle.net/10962/60479 , vital:27784
- Description: The focus of this paper is an exploration of curating and its various forms as understood in a South African art context. In order to understand this context I examine definitions of South African publics as well as different curatorial models. I raise questions around art and accessibility as well as the functions of language as a gate keeper within the visual arts. Through a practical exploration of curatorial methods of engagement, I assess the curator's role as disseminator of information. My final project Conversations at Morija that was held in Morija, Lesotho faces the challenge of curating within a space that has a strong creative platform, but lacks a visual art audience. The exhibition was held during the 2013 Morija Art and Culture festival which is dominated by its music component. Despite Morija being the country's creative centre and sole museum, there is little support for its programme both monetary and in terms of attendance. Through a series of conversations several issues pertaining to Morija, Lesotho and the diaspora were addressed. I look at the absence of creative platforms and alternative curatorial methods that engage the public in a participatory manner. Briefly exploring questions of migrant labour and definitions of what constitutes a diaspora. I look at relatable ways to engage the local audience whilst maintaining a creative core in which to spark dialogue around pertinent matters relating to the country.
- Full Text:
Formulation of an enzyme cocktail, HoloMix, using cellulolytic and xylanolytic enzyme core-sets for effective degradation of various pre-treated hardwoods
- Authors: Malgas, Samkelo
- Date: 2018
- Subjects: Biomass , Cellulase , Hardwoods , Xylanases
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/62827 , vital:28297 , DOI https://doi.org/10.21504/10962/62827
- Description: Currently, there is a growing interest in utilising hardwoods as feedstocks for bioethanol production due to the vast advantages they have over other feedstocks for fermentable sugar production. In this study, two selected hardwoods, Acacia and Populus spp., were subjected to two pre-treatment processes (Sodium chlorite delignification and Steam explosion) and compared with respect to how these pre-treatments affect their enzymatic saccharification. Hardwoods were selected for this study, because hardwoods are easier to delignify when compared to softwoods, and therefore their polysaccharides are more easily accessible by enzymes for the purpose of producing fermentable sugars. Currently available commercial enzyme mixtures have been developed for optimal hydrolysis of acid-pre-treated corn stover and are therefore not optimal for saccharification of pre-treated hardwoods. In this work, we attempted the empirical design of a hardwood specific enzyme cocktail, HoloMix. Firstly, a cellulolytic core-set, CelMix (in a ratio of Egl 68%: Cel7A 17%: Cel6A 6%: Bgl1 9%), for the optimal release of glucose, and a xylanolytic core-set, XynMix (in a ratio of Xyn2A 60%: XT6 20%: AguA 11%: SXA 9%), for the optimal release of xylose, were formulated using an empirical enzyme ratio approach after biochemically characterising these enzymes. As it is well ̶ known that biomass pre-treatment may result in the generation of compounds that hamper enzymatic hydrolysis and microbial fermentation, the effects of these compounds on CelMix and XynMix were evaluated. Using the optimised CelMix and XynMix cocktails, a HoloMix cocktail was established for optimal reducing sugar, glucose and xylose release from the various pre-treated hardwoods. For delignified biomass, the optimized HoloMix consisted of CelMix to XynMix at 75% to 25% protein loading, while for the untreated and steam exploded biomass the HoloMix consisted of CelMix to XynMix at 93.75% to 6.25% protein loading. Sugar release by the HoloMix at a loading of 27.5 mg protein/g of biomass (or 55 mg protein/g of glucan) after 24 h gave 70-100% sugar yield. Treatment of the hardwoods with a laccase from Agaricus bisporus, especially wood biomass with a higher proportion of lignin, significantly improved saccharification by the formulated HoloMix enzyme cocktails. This study provided insights into the enzymatic hydrolysis of various pre-treated hardwood substrates and assessed whether the same lignocellulolytic cocktail can be used to efficiently hydrolyse different hardwood species. The present study also demonstrated that the hydrolysis efficiency of the optimised HoloMix was comparable to (if not better) than commercial enzyme preparations during hardwood biomass saccharification. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2018
- Full Text:
- Authors: Malgas, Samkelo
- Date: 2018
- Subjects: Biomass , Cellulase , Hardwoods , Xylanases
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/62827 , vital:28297 , DOI https://doi.org/10.21504/10962/62827
- Description: Currently, there is a growing interest in utilising hardwoods as feedstocks for bioethanol production due to the vast advantages they have over other feedstocks for fermentable sugar production. In this study, two selected hardwoods, Acacia and Populus spp., were subjected to two pre-treatment processes (Sodium chlorite delignification and Steam explosion) and compared with respect to how these pre-treatments affect their enzymatic saccharification. Hardwoods were selected for this study, because hardwoods are easier to delignify when compared to softwoods, and therefore their polysaccharides are more easily accessible by enzymes for the purpose of producing fermentable sugars. Currently available commercial enzyme mixtures have been developed for optimal hydrolysis of acid-pre-treated corn stover and are therefore not optimal for saccharification of pre-treated hardwoods. In this work, we attempted the empirical design of a hardwood specific enzyme cocktail, HoloMix. Firstly, a cellulolytic core-set, CelMix (in a ratio of Egl 68%: Cel7A 17%: Cel6A 6%: Bgl1 9%), for the optimal release of glucose, and a xylanolytic core-set, XynMix (in a ratio of Xyn2A 60%: XT6 20%: AguA 11%: SXA 9%), for the optimal release of xylose, were formulated using an empirical enzyme ratio approach after biochemically characterising these enzymes. As it is well ̶ known that biomass pre-treatment may result in the generation of compounds that hamper enzymatic hydrolysis and microbial fermentation, the effects of these compounds on CelMix and XynMix were evaluated. Using the optimised CelMix and XynMix cocktails, a HoloMix cocktail was established for optimal reducing sugar, glucose and xylose release from the various pre-treated hardwoods. For delignified biomass, the optimized HoloMix consisted of CelMix to XynMix at 75% to 25% protein loading, while for the untreated and steam exploded biomass the HoloMix consisted of CelMix to XynMix at 93.75% to 6.25% protein loading. Sugar release by the HoloMix at a loading of 27.5 mg protein/g of biomass (or 55 mg protein/g of glucan) after 24 h gave 70-100% sugar yield. Treatment of the hardwoods with a laccase from Agaricus bisporus, especially wood biomass with a higher proportion of lignin, significantly improved saccharification by the formulated HoloMix enzyme cocktails. This study provided insights into the enzymatic hydrolysis of various pre-treated hardwood substrates and assessed whether the same lignocellulolytic cocktail can be used to efficiently hydrolyse different hardwood species. The present study also demonstrated that the hydrolysis efficiency of the optimised HoloMix was comparable to (if not better) than commercial enzyme preparations during hardwood biomass saccharification. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2018
- Full Text:
Formulation, characterisation and optimisation of self-nanoemulsifying drug delivery systems (SNEDDS) loaded with artemether and lumefantrine
- Authors: Mudyahoto, Tsitsi
- Date: 2018
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63503 , vital:28422
- Description: Expected release date-April 2020
- Full Text:
- Authors: Mudyahoto, Tsitsi
- Date: 2018
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63503 , vital:28422
- Description: Expected release date-April 2020
- Full Text:
From deviant choice to feminist issue: An historical analysis of scholarship on voluntary childlessness (1920–2013)
- Lynch, Ingrid, Morison, Tracy, Macleod, Catriona I, Mijas, Magdalena, du Toit, Ryan, Shivakumar, Seemanthini T
- Authors: Lynch, Ingrid , Morison, Tracy , Macleod, Catriona I , Mijas, Magdalena , du Toit, Ryan , Shivakumar, Seemanthini T
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/434319 , vital:73048 , ISBN 978-1-78754-361-4 , https://www.emerald.com/insight/content/doi/10.1108/978-1-78754-361-420181002/full/html
- Description: Existing reviews of research on voluntary childlessness generally take the form of narrative summaries, focusing on main topics investigated over time. In this chapter, the authors extend previous literature reviews to conduct a systematic review and content analysis of socio-historical and geopolitical aspects of knowledge production about voluntary childlessness. The dataset comprised 195 peer-reviewed articles that were coded and analysed to explore, inter alia: the main topic under investigation; country location of authors; sample characteristics; theoretical framework and methodology. The findings are discussed in relation to the socio-historical contexts of knowledge production, drawing on theoretical insights concerned with the politics of location, representation and research practice. The shifts in the topics of research from the 1970s, when substantial research first emerged, uphold the view of voluntary childlessness as non-normative. With some regional variation, knowledge is dominated by quantitative, hard science methodologies and mostly generated about privileged, married women living in the global North. The implications of this for future research concerned with reproductive freedom are outlined.
- Full Text:
- Authors: Lynch, Ingrid , Morison, Tracy , Macleod, Catriona I , Mijas, Magdalena , du Toit, Ryan , Shivakumar, Seemanthini T
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/434319 , vital:73048 , ISBN 978-1-78754-361-4 , https://www.emerald.com/insight/content/doi/10.1108/978-1-78754-361-420181002/full/html
- Description: Existing reviews of research on voluntary childlessness generally take the form of narrative summaries, focusing on main topics investigated over time. In this chapter, the authors extend previous literature reviews to conduct a systematic review and content analysis of socio-historical and geopolitical aspects of knowledge production about voluntary childlessness. The dataset comprised 195 peer-reviewed articles that were coded and analysed to explore, inter alia: the main topic under investigation; country location of authors; sample characteristics; theoretical framework and methodology. The findings are discussed in relation to the socio-historical contexts of knowledge production, drawing on theoretical insights concerned with the politics of location, representation and research practice. The shifts in the topics of research from the 1970s, when substantial research first emerged, uphold the view of voluntary childlessness as non-normative. With some regional variation, knowledge is dominated by quantitative, hard science methodologies and mostly generated about privileged, married women living in the global North. The implications of this for future research concerned with reproductive freedom are outlined.
- Full Text:
From universal to local: perspectives on cultural landscape heritage in South Africa
- Cocks, Michelle L, Vetter, Susan M, Wiersum, K Freerk
- Authors: Cocks, Michelle L , Vetter, Susan M , Wiersum, K Freerk
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141150 , vital:37948 , https://doi.org/10.1080/13527258.2017.1362573
- Description: The concept of cultural landscapes relates to the multifaceted links between people, place and identity. From a professional perspective, the concept refers to a category of designated conservation areas with specific biocultural heritage values. From a local perspective, it may refer to a landscape that is associated with the provision of a culturally-specific sense of identity and belonging. We explore these two perspectives through a comparative analysis of three cultural landscapes in South Africa, the ‘expert’ designated Mapungubwe Cultural Landscape and the Richtersveld Cultural and Botanical Landscape, and the local associative landscape of emaXhoseni, which is not formally recognised. We propose that a biocultural diversity perspective of heritage not only recognises the inextricable relationship between nature and culture, but it also gives prominence to the beliefs, values and practices of local people, and to strengthening their agency to safeguard their heritage in ways and forms that are relevant to them.
- Full Text:
- Authors: Cocks, Michelle L , Vetter, Susan M , Wiersum, K Freerk
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141150 , vital:37948 , https://doi.org/10.1080/13527258.2017.1362573
- Description: The concept of cultural landscapes relates to the multifaceted links between people, place and identity. From a professional perspective, the concept refers to a category of designated conservation areas with specific biocultural heritage values. From a local perspective, it may refer to a landscape that is associated with the provision of a culturally-specific sense of identity and belonging. We explore these two perspectives through a comparative analysis of three cultural landscapes in South Africa, the ‘expert’ designated Mapungubwe Cultural Landscape and the Richtersveld Cultural and Botanical Landscape, and the local associative landscape of emaXhoseni, which is not formally recognised. We propose that a biocultural diversity perspective of heritage not only recognises the inextricable relationship between nature and culture, but it also gives prominence to the beliefs, values and practices of local people, and to strengthening their agency to safeguard their heritage in ways and forms that are relevant to them.
- Full Text:
Funding higher education and training in South Africa: a comparative study of tax incentive measures, in conjunction with a dedicated tax
- Authors: Holm, Darryn
- Date: 2018
- Subjects: Education, Higher -- Finance , Education, Higher -- South Africa , Tax incentives -- Law and legislation -- South Africa , Student aid -- South Africa , Universities and Colleges -- Taxation -- Law and legislation -- South Africa , South Africa. Income Tax Act, 1962
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/59445 , vital:27606
- Description: Higher education and training in South Africa in the post-Apartheid era has never been more volatile than it is currently, some two decades into democracy. Despite the many advances and achievements of higher education, the student protests of 2015 and 2016 have given expression to underlying fault-lines, including increasing student expectations and frustrations with regard to access and funding. This research was undertaken to document the underlying historical issues and models pertaining to funding within the higher education and training sector as well as the existing higher education and training taxation policies and incentives enacted in South Africa and selected international jurisdictions. This was done with a view to providing a framework for higher education and training tax policy formation in South Africa to assist in meeting its higher education and training “access and affordability” targets as set out in the National Plan on Higher Education and the Higher Education White Paper, while at the same time not hindering economic growth. A doctrinal research methodology was adopted in this study as it mainly analysed and interpreted legislation and policy documents and therefore the approach was qualitative in nature. An extensive literature survey was done in order to document the various internationally selected legislated higher education and training tax policies and incentives. The literature indicated that there are widespread funding perspectives and initiates, and that international tax policies enacted with the aim of ensuring that higher education and training is more accessible and affordable to the public, is stable and effective in certain jurisdictions. It is submitted that while a higher education dedicated tax may not be sufficiently effective in South Africa, a combination of broad-based tax incentives will help to promote the change to a more affordable and stable higher education funding system, whilst not preventing growth through sustainable development.
- Full Text:
- Authors: Holm, Darryn
- Date: 2018
- Subjects: Education, Higher -- Finance , Education, Higher -- South Africa , Tax incentives -- Law and legislation -- South Africa , Student aid -- South Africa , Universities and Colleges -- Taxation -- Law and legislation -- South Africa , South Africa. Income Tax Act, 1962
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/59445 , vital:27606
- Description: Higher education and training in South Africa in the post-Apartheid era has never been more volatile than it is currently, some two decades into democracy. Despite the many advances and achievements of higher education, the student protests of 2015 and 2016 have given expression to underlying fault-lines, including increasing student expectations and frustrations with regard to access and funding. This research was undertaken to document the underlying historical issues and models pertaining to funding within the higher education and training sector as well as the existing higher education and training taxation policies and incentives enacted in South Africa and selected international jurisdictions. This was done with a view to providing a framework for higher education and training tax policy formation in South Africa to assist in meeting its higher education and training “access and affordability” targets as set out in the National Plan on Higher Education and the Higher Education White Paper, while at the same time not hindering economic growth. A doctrinal research methodology was adopted in this study as it mainly analysed and interpreted legislation and policy documents and therefore the approach was qualitative in nature. An extensive literature survey was done in order to document the various internationally selected legislated higher education and training tax policies and incentives. The literature indicated that there are widespread funding perspectives and initiates, and that international tax policies enacted with the aim of ensuring that higher education and training is more accessible and affordable to the public, is stable and effective in certain jurisdictions. It is submitted that while a higher education dedicated tax may not be sufficiently effective in South Africa, a combination of broad-based tax incentives will help to promote the change to a more affordable and stable higher education funding system, whilst not preventing growth through sustainable development.
- Full Text:
FyaMoneka: exploring the erasure of women within Zambian history
- Authors: Kalichini, Gladys Melina
- Date: 2018
- Subjects: Women -- Zambia -- Historiography , Women -- Zambia -- History , Women -- Political activity -- Zambia , Women -- Zambia -- Social conditions , Collective memory -- Zambia , Death in art , Feminism -- Zambia , Male domination (Social structure) -- Zambia , Sex discrimination against women -- Zambia
- Language: English
- Type: text , Thesis , Masters , MFA
- Identifier: http://hdl.handle.net/10962/63186 , vital:28371
- Description: This Master of Fine Art submission, comprising of an exhibition and mini-thesis, explores the erasure of women’s narratives from Zambian history and collective memory. As a point of entry into the broader conversation of narratives of women marginalised in certain historicised events, this research analyses the narratives of Julia Chikamoneka and Alice Lenshina that are held in the collective memory of Zambian history. It focuses on the representations of narratives of women during and beyond colonial times, while hinging particularly on these two characters’ encounters with and against British rule in Northern Rhodesia (Zambia). Titled FyaMoneka: Exploring the Erasure of Women Within Zambian History, the mini-thesis examines the representations and positioning of women’s political activities within the liberation narrative that is recorded in the National Archives of Zambia (NAZ) and the United National Independence Party (UNIP) Archives. This mini-thesis highlights the fact that women have been written out of Zambia’s liberation narrative in the NAZ and the UNIP Archives, and remains mindful of the inherent modifications and erasures of women’s accounts over time, including the obfuscation or the absence of certain archival materials. This mini-thesis prospectively reconstructs Chikamoneka’s and Lenshina’s narratives using traces of their histories within collective memory through re/visiting processes of re-archivisation. The exhibition, titled ChaMoneka (It Has Become Visible): UnCasting Shadows, explores death and representations of death, where death is conceptualised as a metaphor for the erasure of women’s historical narratives, whereas the body represents the narrative. Based on an exploration of the relationship and tensions between collective memory and history, death within this exhibition is thematised as the course of fading away and a continuous process in which women’s narratives are erased.
- Full Text:
- Authors: Kalichini, Gladys Melina
- Date: 2018
- Subjects: Women -- Zambia -- Historiography , Women -- Zambia -- History , Women -- Political activity -- Zambia , Women -- Zambia -- Social conditions , Collective memory -- Zambia , Death in art , Feminism -- Zambia , Male domination (Social structure) -- Zambia , Sex discrimination against women -- Zambia
- Language: English
- Type: text , Thesis , Masters , MFA
- Identifier: http://hdl.handle.net/10962/63186 , vital:28371
- Description: This Master of Fine Art submission, comprising of an exhibition and mini-thesis, explores the erasure of women’s narratives from Zambian history and collective memory. As a point of entry into the broader conversation of narratives of women marginalised in certain historicised events, this research analyses the narratives of Julia Chikamoneka and Alice Lenshina that are held in the collective memory of Zambian history. It focuses on the representations of narratives of women during and beyond colonial times, while hinging particularly on these two characters’ encounters with and against British rule in Northern Rhodesia (Zambia). Titled FyaMoneka: Exploring the Erasure of Women Within Zambian History, the mini-thesis examines the representations and positioning of women’s political activities within the liberation narrative that is recorded in the National Archives of Zambia (NAZ) and the United National Independence Party (UNIP) Archives. This mini-thesis highlights the fact that women have been written out of Zambia’s liberation narrative in the NAZ and the UNIP Archives, and remains mindful of the inherent modifications and erasures of women’s accounts over time, including the obfuscation or the absence of certain archival materials. This mini-thesis prospectively reconstructs Chikamoneka’s and Lenshina’s narratives using traces of their histories within collective memory through re/visiting processes of re-archivisation. The exhibition, titled ChaMoneka (It Has Become Visible): UnCasting Shadows, explores death and representations of death, where death is conceptualised as a metaphor for the erasure of women’s historical narratives, whereas the body represents the narrative. Based on an exploration of the relationship and tensions between collective memory and history, death within this exhibition is thematised as the course of fading away and a continuous process in which women’s narratives are erased.
- Full Text:
Gaining cyber security insight through an analysis of open source intelligence data: an East African case study
- Authors: Chindipha, Stones Dalitso
- Date: 2018
- Subjects: Open source intelligence -- Africa, East , Computer security -- Africa, East , Computer networks -- Security measures -- Africa, East , Denial of service attacks -- Africa, East , Sentient Hvper-Optimised Data Access Network (SHODAN) , Internet Background Radiation (IBR)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/60618 , vital:27805
- Description: With each passing year the number of Internet users and connected devices grows, and this is particularly so in Africa. This growth brings with it an increase in the prevalence cyber-attacks. Looking at the current state of affairs, cybersecurity incidents are more likely to increase in African countries mainly due to the increased prevalence and affordability of broadband connectivity which is coupled with lack of online security awareness. The adoption of mobile banking has aggravated the situation making the continent more attractive to hackers who bank on the malpractices of users. Using Open Source Intelligence (OSINT) data sources like Sentient Hvper-Optimised Data Access Network (SHODAN) and Internet Background Radiation (IBR), this research explores the prevalence of vulnerabilities and their accessibility to evber threat actors. The research focuses on the East African Community (EAC) comprising of Tanzania, Kenya, Malawi, and Uganda, An IBR data set collected by a Rhodes University network telescope spanning over 72 months was used in this research, along with two snapshot period of data from the SHODAN project. The findings shows that there is a significant risk to systems within the EAC, particularly using the SHODAN data. The MITRE CVSS threat scoring system was applied to this research using FREAK and Heartbleed as sample vulnerabilities identified in EAC, When looking at IBR, the research has shown that attackers can use either destination ports or IP source addresses to perform an attack which if not attended to may be reused yearly until later on move to the allocated IP address space once it starts making random probes. The moment it finds one vulnerable client on the network it spreads throughout like a worm, DDoS is one the attacks that can be generated from IBR, Since the SHODAN dataset had two collection points, the study has shown the changes that have occurred in Malawi and Tanzania for a period of 14 months by using three variables i.e, device type, operating systems, and ports. The research has also identified vulnerable devices in all the four countries. Apart from that, the study identified operating systems, products, OpenSSL, ports and ISPs as some of the variables that can be used to identify vulnerabilities in systems. In the ease of OpenSSL and products, this research went further by identifying the type of attack that can occur and its associated CVE-ID.
- Full Text:
- Authors: Chindipha, Stones Dalitso
- Date: 2018
- Subjects: Open source intelligence -- Africa, East , Computer security -- Africa, East , Computer networks -- Security measures -- Africa, East , Denial of service attacks -- Africa, East , Sentient Hvper-Optimised Data Access Network (SHODAN) , Internet Background Radiation (IBR)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/60618 , vital:27805
- Description: With each passing year the number of Internet users and connected devices grows, and this is particularly so in Africa. This growth brings with it an increase in the prevalence cyber-attacks. Looking at the current state of affairs, cybersecurity incidents are more likely to increase in African countries mainly due to the increased prevalence and affordability of broadband connectivity which is coupled with lack of online security awareness. The adoption of mobile banking has aggravated the situation making the continent more attractive to hackers who bank on the malpractices of users. Using Open Source Intelligence (OSINT) data sources like Sentient Hvper-Optimised Data Access Network (SHODAN) and Internet Background Radiation (IBR), this research explores the prevalence of vulnerabilities and their accessibility to evber threat actors. The research focuses on the East African Community (EAC) comprising of Tanzania, Kenya, Malawi, and Uganda, An IBR data set collected by a Rhodes University network telescope spanning over 72 months was used in this research, along with two snapshot period of data from the SHODAN project. The findings shows that there is a significant risk to systems within the EAC, particularly using the SHODAN data. The MITRE CVSS threat scoring system was applied to this research using FREAK and Heartbleed as sample vulnerabilities identified in EAC, When looking at IBR, the research has shown that attackers can use either destination ports or IP source addresses to perform an attack which if not attended to may be reused yearly until later on move to the allocated IP address space once it starts making random probes. The moment it finds one vulnerable client on the network it spreads throughout like a worm, DDoS is one the attacks that can be generated from IBR, Since the SHODAN dataset had two collection points, the study has shown the changes that have occurred in Malawi and Tanzania for a period of 14 months by using three variables i.e, device type, operating systems, and ports. The research has also identified vulnerable devices in all the four countries. Apart from that, the study identified operating systems, products, OpenSSL, ports and ISPs as some of the variables that can be used to identify vulnerabilities in systems. In the ease of OpenSSL and products, this research went further by identifying the type of attack that can occur and its associated CVE-ID.
- Full Text:
Gender and popular imaginaries in Africa:
- Spencer, Lynda G, Ligaga, Dina, Musila, Grace
- Authors: Spencer, Lynda G , Ligaga, Dina , Musila, Grace
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/138860 , vital:37679 , DOI: 10.1080/10130950.2018.1526467
- Description: If we accept that many Africans’ social perceptions on a range of questions, including gender, are shaped by popular cultural productions which retain a keen pulse on the everyday, then it is important to reflect on the interface between gender and popular imaginaries. The debate on the definition of the ‘popular’ remains an open one with multiple interpretations and categories. This contestation in itself gestures towards popular culture’s inclination for ambiguity and slipperiness. As Karin Barber (2018:13) reminds us, the popular constitutes “expressive forms that are constantly emergent, ephemeral, embedded in daily life, given to extraordinary bursts of activity and rapid transformation”. For George Ogola, popular cultural forms “engage with and subject the polity to constant critique through informal but widely recognised forms of censure” (2017:2). In this special issue, we use popular imaginaries to mean the range of cultural productions, platforms, and interactions between consumers and producers - which are often interchangeable - that capture the material, the affective, as inflected and refracted in different texts, contexts and platforms.
- Full Text:
- Authors: Spencer, Lynda G , Ligaga, Dina , Musila, Grace
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/138860 , vital:37679 , DOI: 10.1080/10130950.2018.1526467
- Description: If we accept that many Africans’ social perceptions on a range of questions, including gender, are shaped by popular cultural productions which retain a keen pulse on the everyday, then it is important to reflect on the interface between gender and popular imaginaries. The debate on the definition of the ‘popular’ remains an open one with multiple interpretations and categories. This contestation in itself gestures towards popular culture’s inclination for ambiguity and slipperiness. As Karin Barber (2018:13) reminds us, the popular constitutes “expressive forms that are constantly emergent, ephemeral, embedded in daily life, given to extraordinary bursts of activity and rapid transformation”. For George Ogola, popular cultural forms “engage with and subject the polity to constant critique through informal but widely recognised forms of censure” (2017:2). In this special issue, we use popular imaginaries to mean the range of cultural productions, platforms, and interactions between consumers and producers - which are often interchangeable - that capture the material, the affective, as inflected and refracted in different texts, contexts and platforms.
- Full Text:
General features and kinetic analysis of thermoluminescence from annealed natural quartz
- Thomas, Sunil, Chithambo, Makaiko L
- Authors: Thomas, Sunil , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/112885 , vital:33670 , https://doi.org/10.1016/j.jlumin.2018.02.003
- Description: The aim of this study is to explore the thermoluminescence properties of beta irradiated natural quartz annealed at 900 °C, that is, beyond its second phase inversion temperature of 867 °C. The sample was annealed to improve its sensitivity and to deplete any residual charge from electron traps. The glow-curve corresponding to 10 Gy shows three peaks when measured at 1 °C/s; a dominant one at 71 °C, the subject of this report, and two other ones at 125 and 177 °C. The dose response of the main peak was studied in the range 1–300 Gy. The activation energy of the main glow-peak was evaluated as ~1 eV. Kinetic analyses using various methods show that the main glow-peak follows first order kinetics.
- Full Text: false
- Authors: Thomas, Sunil , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/112885 , vital:33670 , https://doi.org/10.1016/j.jlumin.2018.02.003
- Description: The aim of this study is to explore the thermoluminescence properties of beta irradiated natural quartz annealed at 900 °C, that is, beyond its second phase inversion temperature of 867 °C. The sample was annealed to improve its sensitivity and to deplete any residual charge from electron traps. The glow-curve corresponding to 10 Gy shows three peaks when measured at 1 °C/s; a dominant one at 71 °C, the subject of this report, and two other ones at 125 and 177 °C. The dose response of the main peak was studied in the range 1–300 Gy. The activation energy of the main glow-peak was evaluated as ~1 eV. Kinetic analyses using various methods show that the main glow-peak follows first order kinetics.
- Full Text: false