An Archive of Upset : the Shift from Commissioning to Curating through South Africa’s Representations at the Bienal de São Paulo and the Interstitial Nexus of Leonard Tshehla Mohapi Matsoso
- Authors: Dantas, Nancy Isabel
- Date: 2021-04
- Subjects: Bienal Internacional de São Paulo , Curatorship , Art -- Commissioning , Art -- Political aspects , Matsoso, Leonard Tshehla Mohapi
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/174492 , vital:42482 , https://doi.org/10.21504/10962/174492
- Description: This thesis explores the distinction between commissioning and curating, adopting the Bienal de São Paulo (or Bienal) as its conceptual propeller and point of departure. The thesis regards exhibitions as palimpsests, in other words, platforms built on previous conscious or sublimated models, beyond the Venetian model inaugurated in 1895. By looking at world expositions, particularly the Cape presence at the Colonial and Indian Exhibition of 1886, this project traces a lineage of commissioners, from Sir Henry Cole to Sydney Cowper through to the Director of the Pretoria Art Museum, Albert Werth. It distinguishes these men, their vision and allegiances from the curatorial model instantiated in South Africa by the late Okwui Enwezor as a consequence of the Second Johannesburg Biennale, held in 1997. The aim of this research has been to provide a partial but crucial account of this shift, and to remain attentive to the silences and deletions, to what happens in the interstice, at transitionary moments of ‘betweenness.’ I ask that readers consider the 1979 Bienal as an instance of an interstice where the occluded and silenced ghost of modernist artist Leonard Tshehla Mohapi Matsoso, who represented South Africa at the 1973 edition of the Bienal, garnering a substantial award for his work in drawing, resides. Matsoso was the first and only Black South African artist to receive this accolade. This thesis posits that Matsoso’s absence from the exhibition in 1979, an exhibition where he would rightly have featured, constitutes a curatorial haunting, wedged in the archive of the Bienal’s history, and an opportunity for revision and evaluation of commissioning vis-àvis curating. In reading the exhibition histories’ archive “along the grain” (Stoler 2002), the commissioner emerges as a man of letters, a privileged social category found in the archive; a colonial authority whose status was founded as much on his display of European learning as on his studied ignorance of local knowledge; an implementer of the taxonomic state and modernist art historical canon (in the case of Werth); a cultivator of the fine arts of deference, dissemblance and persuasion. At a later stage and moment of dissonance and disruption, the independent curator emerges to reconsider, question and expand the canon, distancing him/herself from the (South African) State to serve the artist or artists and a wider community. This research aims to contribute, albeit in a small way, to a reappraisal of the position of Leonard Tshehla Mohapi Matsoso in South African modernism, and the distinction between commissioning and curating. , Thesis (PhD)--Rhodes University, Faculty of Humanities, Department of Fine Art, 2021
- Full Text:
- Authors: Dantas, Nancy Isabel
- Date: 2021-04
- Subjects: Bienal Internacional de São Paulo , Curatorship , Art -- Commissioning , Art -- Political aspects , Matsoso, Leonard Tshehla Mohapi
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/174492 , vital:42482 , https://doi.org/10.21504/10962/174492
- Description: This thesis explores the distinction between commissioning and curating, adopting the Bienal de São Paulo (or Bienal) as its conceptual propeller and point of departure. The thesis regards exhibitions as palimpsests, in other words, platforms built on previous conscious or sublimated models, beyond the Venetian model inaugurated in 1895. By looking at world expositions, particularly the Cape presence at the Colonial and Indian Exhibition of 1886, this project traces a lineage of commissioners, from Sir Henry Cole to Sydney Cowper through to the Director of the Pretoria Art Museum, Albert Werth. It distinguishes these men, their vision and allegiances from the curatorial model instantiated in South Africa by the late Okwui Enwezor as a consequence of the Second Johannesburg Biennale, held in 1997. The aim of this research has been to provide a partial but crucial account of this shift, and to remain attentive to the silences and deletions, to what happens in the interstice, at transitionary moments of ‘betweenness.’ I ask that readers consider the 1979 Bienal as an instance of an interstice where the occluded and silenced ghost of modernist artist Leonard Tshehla Mohapi Matsoso, who represented South Africa at the 1973 edition of the Bienal, garnering a substantial award for his work in drawing, resides. Matsoso was the first and only Black South African artist to receive this accolade. This thesis posits that Matsoso’s absence from the exhibition in 1979, an exhibition where he would rightly have featured, constitutes a curatorial haunting, wedged in the archive of the Bienal’s history, and an opportunity for revision and evaluation of commissioning vis-àvis curating. In reading the exhibition histories’ archive “along the grain” (Stoler 2002), the commissioner emerges as a man of letters, a privileged social category found in the archive; a colonial authority whose status was founded as much on his display of European learning as on his studied ignorance of local knowledge; an implementer of the taxonomic state and modernist art historical canon (in the case of Werth); a cultivator of the fine arts of deference, dissemblance and persuasion. At a later stage and moment of dissonance and disruption, the independent curator emerges to reconsider, question and expand the canon, distancing him/herself from the (South African) State to serve the artist or artists and a wider community. This research aims to contribute, albeit in a small way, to a reappraisal of the position of Leonard Tshehla Mohapi Matsoso in South African modernism, and the distinction between commissioning and curating. , Thesis (PhD)--Rhodes University, Faculty of Humanities, Department of Fine Art, 2021
- Full Text:
An assessment of the wild cyclopia subternata (vleitee) resource
- Authors: Van der Walt, Wouter
- Date: 2021-04
- Subjects: Legumes -- South Africa , Fynbos -- South Africa , Fynbos ecology -- South Africa , Fynbos -- Harvesting -- South Africa , Biodiversity conservation -- South Africa , Traditional ecological knowledge -- South Africa , Wild Cyclopia Subternata (Vleitee) , Honeybush tea industry
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/176874 , vital:42767
- Description: Cyclopia spp. is used for the production of Honeybush tea, an herbal tea which is used in many cases as a substitute for rooibos tea. The wild harvesting of this fynbos plant still brings in up to 85% of the annual crop and as such needs to be carefully monitored in order to avoid over harvesting and the destruction of biodiversity within the Eastern and Western Cape mountain regions of Southern Africa. Due to the concerns of overharvesting and unsuitable use of the wild resource issues of supply security have been raised. There is a lack of formal knowledge relating to the plant, its harvesting, the industry and its economic potential. This study aimed to amend this scarcity by contributing to the knowledge of C. subternata as a wild harvested plant, the physical environment favoured by C. subternata, sustainable use through harvesting of the wild plant and harvesting methods specific to this honeybush species. The research concludes by presenting a guideline for best harvest practices of the wild C. subternata plant. , Thesis (MSc) -- Faculty of Science, Department of Geography, 2021
- Full Text:
- Authors: Van der Walt, Wouter
- Date: 2021-04
- Subjects: Legumes -- South Africa , Fynbos -- South Africa , Fynbos ecology -- South Africa , Fynbos -- Harvesting -- South Africa , Biodiversity conservation -- South Africa , Traditional ecological knowledge -- South Africa , Wild Cyclopia Subternata (Vleitee) , Honeybush tea industry
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/176874 , vital:42767
- Description: Cyclopia spp. is used for the production of Honeybush tea, an herbal tea which is used in many cases as a substitute for rooibos tea. The wild harvesting of this fynbos plant still brings in up to 85% of the annual crop and as such needs to be carefully monitored in order to avoid over harvesting and the destruction of biodiversity within the Eastern and Western Cape mountain regions of Southern Africa. Due to the concerns of overharvesting and unsuitable use of the wild resource issues of supply security have been raised. There is a lack of formal knowledge relating to the plant, its harvesting, the industry and its economic potential. This study aimed to amend this scarcity by contributing to the knowledge of C. subternata as a wild harvested plant, the physical environment favoured by C. subternata, sustainable use through harvesting of the wild plant and harvesting methods specific to this honeybush species. The research concludes by presenting a guideline for best harvest practices of the wild C. subternata plant. , Thesis (MSc) -- Faculty of Science, Department of Geography, 2021
- Full Text:
An evaluation of synergistic interactions between feruloyl esterases and xylanases during the hydrolysis of various pre-treated agricultural residues
- Authors: Mkabayi, Lithalethu
- Date: 2021-04
- Subjects: Esterases , Xylanases , Hydrolysis , Agricultural wastes -- Recycling , Enzymes , Lignocellulose -- Biodegradation , Escherichia coli , Oligosaccharides , Hydroxycinnamic acids
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/178224 , vital:42922 , 10.21504/10962/178224
- Description: Agricultural residues are readily available and inexpensive renewable resources that can be used as raw materials for the production of value-added chemicals. The application of enzymes to facilitate the degradation of agricultural residues has long been considered the most environmentally friendly strategy for converting this material into good quality value-added chemicals. However, agricultural residues are typically lignocellulosic in composition and recalcitrant to enzymatic hydrolysis. Due to this recalcitrant nature, the complete degradation of biomass residues requires the synergistic action of a broad range of enzymes. The development and optimisation of synergistic enzyme cocktails is an effective approach for achieving high hydrolysis efficiency of lignocellulosic biomass. The aim of the current study was to evaluate the synergistic interactions between two termite metagenome-derived feruloyl esterases (FAE6 and FAE5) and endo-xylanases for the production of hydroxycinnamic acids and xylo-oligosaccharides (XOS) from model substrates, and untreated and pre-treated agricultural residues. Firstly, the two fae genes were heterologously expressed in Escherichia coli, and the recombinant enzymes were purified to homogeneity. The biochemical properties of the purified recombinant FAEs and xylanases (XT6 and Xyn11) were then assessed to determine the factors which influenced their activities and to select suitable operating conditions for synergy studies. An optimal protein loading ratio of xylanases to FAEs required to maximise the release of both reducing sugar and ferulic acid (FA) was established using 0.5% (w/v) insoluble wheat arabinoxylan (a model substrate). The enzyme combination of 66% xylanase and 33% FAE (on a protein loading basis) produced the highest amounts of reducing sugars and FA. The enzyme combination of XT6 (GH10 xylanase) and FAE5 or FAE6 liberated the highest amount of FA while a combination of Xyn11 (GH11 xylanase) and FAE5 or FAE6 produced the highest reducing sugar content. The synergistic interactions which were established between the xylanases and FAEs were further investigated using agricultural residues (corn cobs, rice straw and sugarcane bagasse). The three substrates were subjected to hydrothermal and dilute acid pre-treatment prior to synergy studies. It is generally known that, during pre-treatment, many compounds can be produced which may influence enzymatic hydrolysis. The effects of these by-products were assessed and it was found that lignin and its degradation products were the most inhibitory to the FAEs. The optimised enzyme cocktail was then applied to 1% (w/v) of untreated and pre-treated substrates for the efficient production of XOS and hydroxycinnamic acids. A significant improvement in xylanase substrate degradation was observed, especially with the combination of 66% Xyn11 and 33% FAE6 which displayed an improvement in reducing sugars of approximately 1.9-fold and 3.4-fold for hydrothermal and acid pre-treated corn cobs (compared to when Xyn11 was used alone), respectively. The study demonstrated that pre-treatment substantially enhanced the enzymatic hydrolysis of corn cobs and rice straw. Analysis of the hydrolysate product profiles revealed that the optimised enzyme cocktail displayed great potential for releasing XOS with a low degree of polymerisation. In conclusion, this study provided significant insights into the mechanism of synergistic interactions between xylanases and metagenome-derived FAEs during the hydrolysis of various substrates. The study also demonstrated that optimised enzyme cocktails combined with low severity pre-treatment can facilitate the potential use of xylan-rich lignocellulosic biomass for the production of valuable products in the future. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2021
- Full Text:
- Authors: Mkabayi, Lithalethu
- Date: 2021-04
- Subjects: Esterases , Xylanases , Hydrolysis , Agricultural wastes -- Recycling , Enzymes , Lignocellulose -- Biodegradation , Escherichia coli , Oligosaccharides , Hydroxycinnamic acids
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/178224 , vital:42922 , 10.21504/10962/178224
- Description: Agricultural residues are readily available and inexpensive renewable resources that can be used as raw materials for the production of value-added chemicals. The application of enzymes to facilitate the degradation of agricultural residues has long been considered the most environmentally friendly strategy for converting this material into good quality value-added chemicals. However, agricultural residues are typically lignocellulosic in composition and recalcitrant to enzymatic hydrolysis. Due to this recalcitrant nature, the complete degradation of biomass residues requires the synergistic action of a broad range of enzymes. The development and optimisation of synergistic enzyme cocktails is an effective approach for achieving high hydrolysis efficiency of lignocellulosic biomass. The aim of the current study was to evaluate the synergistic interactions between two termite metagenome-derived feruloyl esterases (FAE6 and FAE5) and endo-xylanases for the production of hydroxycinnamic acids and xylo-oligosaccharides (XOS) from model substrates, and untreated and pre-treated agricultural residues. Firstly, the two fae genes were heterologously expressed in Escherichia coli, and the recombinant enzymes were purified to homogeneity. The biochemical properties of the purified recombinant FAEs and xylanases (XT6 and Xyn11) were then assessed to determine the factors which influenced their activities and to select suitable operating conditions for synergy studies. An optimal protein loading ratio of xylanases to FAEs required to maximise the release of both reducing sugar and ferulic acid (FA) was established using 0.5% (w/v) insoluble wheat arabinoxylan (a model substrate). The enzyme combination of 66% xylanase and 33% FAE (on a protein loading basis) produced the highest amounts of reducing sugars and FA. The enzyme combination of XT6 (GH10 xylanase) and FAE5 or FAE6 liberated the highest amount of FA while a combination of Xyn11 (GH11 xylanase) and FAE5 or FAE6 produced the highest reducing sugar content. The synergistic interactions which were established between the xylanases and FAEs were further investigated using agricultural residues (corn cobs, rice straw and sugarcane bagasse). The three substrates were subjected to hydrothermal and dilute acid pre-treatment prior to synergy studies. It is generally known that, during pre-treatment, many compounds can be produced which may influence enzymatic hydrolysis. The effects of these by-products were assessed and it was found that lignin and its degradation products were the most inhibitory to the FAEs. The optimised enzyme cocktail was then applied to 1% (w/v) of untreated and pre-treated substrates for the efficient production of XOS and hydroxycinnamic acids. A significant improvement in xylanase substrate degradation was observed, especially with the combination of 66% Xyn11 and 33% FAE6 which displayed an improvement in reducing sugars of approximately 1.9-fold and 3.4-fold for hydrothermal and acid pre-treated corn cobs (compared to when Xyn11 was used alone), respectively. The study demonstrated that pre-treatment substantially enhanced the enzymatic hydrolysis of corn cobs and rice straw. Analysis of the hydrolysate product profiles revealed that the optimised enzyme cocktail displayed great potential for releasing XOS with a low degree of polymerisation. In conclusion, this study provided significant insights into the mechanism of synergistic interactions between xylanases and metagenome-derived FAEs during the hydrolysis of various substrates. The study also demonstrated that optimised enzyme cocktails combined with low severity pre-treatment can facilitate the potential use of xylan-rich lignocellulosic biomass for the production of valuable products in the future. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2021
- Full Text:
An exploration of working with grade 11 life sciences educators on the use of Virtual Lab to mediate learning of energy transformations
- Authors: Shambare, Brian
- Date: 2021-04
- Subjects: Life sciences -- Study and teaching (Secondary) -- South Africa -- Eastern Cape , Energy conversion -- Study and teaching , Educational technology -- South Africa -- Eastern Cape , Teaching -- Aids and devices , Virtual Lab
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/174388 , vital:42473
- Description: The Department of Basic Education (DBE) examiners’ diagnostic reports for 2012-2019 indicate that National Senior Certificate (NSC) learners mostly perform poorly in examination questions based on scientific investigations. The low performance by learners in these questions has been attributed to the failure by teachers to effectively mediate the learning of scientific concepts due to lack of science laboratories or poorly resourced laboratories in most rural schools. As a result, most learners are finding that scientific concepts are decontextualized and hence abstract. Thus, this study explored making use of Virtual Lab to mediate learning of scientific investigations using the topic Energy transformations. The study was located within an interpretive paradigm and a qualitative case study approach was employed. The study was conducted in four different rural schools in the Joe Gqabi district and seven Grade 11 Life Sciences teachers participated. Data was generated using semi-structured questionnaires, semi-structured interviews, lesson observation, workshop discussions, and journal reflections. The study was informed by Vygotsky’s (1978) Socio-Cultural Theory (SCT) as the theoretical framework, and Thompson and Mishra’s (2006) Technological Pedagogical Content Knowledge (TPACK) as the analytical framework. The results of this study showed that most educators have a positive predisposition towards the integration of Information and Communication Technologies (ICT) in their practice. The study found that using the Virtual Lab to teach Life Sciences has several benefits such as safe environment for conducting experiments; convenience and accessibility; positive teacher and learner attitudes and improvement on learner performance; elimination of physical limitations of a real lab; and availability top-class lab equipment and up-to-date reagents. The study also revealed some shortcomings that were associated with the use of the Virtual Lab. These are; lack of lab partner and peer-learning; and lack of direct supervision by a more knowledgeable facilitator. This study concluded that using the Virtual Lab enhances the quality of teaching scientific experiments in the selected under-resourced rural secondary schools. The study recommends the adoption of the Virtual Lab as a viable alternative to the conventional lab.
- Full Text:
- Authors: Shambare, Brian
- Date: 2021-04
- Subjects: Life sciences -- Study and teaching (Secondary) -- South Africa -- Eastern Cape , Energy conversion -- Study and teaching , Educational technology -- South Africa -- Eastern Cape , Teaching -- Aids and devices , Virtual Lab
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/174388 , vital:42473
- Description: The Department of Basic Education (DBE) examiners’ diagnostic reports for 2012-2019 indicate that National Senior Certificate (NSC) learners mostly perform poorly in examination questions based on scientific investigations. The low performance by learners in these questions has been attributed to the failure by teachers to effectively mediate the learning of scientific concepts due to lack of science laboratories or poorly resourced laboratories in most rural schools. As a result, most learners are finding that scientific concepts are decontextualized and hence abstract. Thus, this study explored making use of Virtual Lab to mediate learning of scientific investigations using the topic Energy transformations. The study was located within an interpretive paradigm and a qualitative case study approach was employed. The study was conducted in four different rural schools in the Joe Gqabi district and seven Grade 11 Life Sciences teachers participated. Data was generated using semi-structured questionnaires, semi-structured interviews, lesson observation, workshop discussions, and journal reflections. The study was informed by Vygotsky’s (1978) Socio-Cultural Theory (SCT) as the theoretical framework, and Thompson and Mishra’s (2006) Technological Pedagogical Content Knowledge (TPACK) as the analytical framework. The results of this study showed that most educators have a positive predisposition towards the integration of Information and Communication Technologies (ICT) in their practice. The study found that using the Virtual Lab to teach Life Sciences has several benefits such as safe environment for conducting experiments; convenience and accessibility; positive teacher and learner attitudes and improvement on learner performance; elimination of physical limitations of a real lab; and availability top-class lab equipment and up-to-date reagents. The study also revealed some shortcomings that were associated with the use of the Virtual Lab. These are; lack of lab partner and peer-learning; and lack of direct supervision by a more knowledgeable facilitator. This study concluded that using the Virtual Lab enhances the quality of teaching scientific experiments in the selected under-resourced rural secondary schools. The study recommends the adoption of the Virtual Lab as a viable alternative to the conventional lab.
- Full Text:
An exploratory investigation into an Integrated Vulnerability and Patch Management Framework
- Authors: Carstens, Duane
- Date: 2021-04
- Subjects: Computer security , Computer security -- Management , Computer networks -- Security measures , Patch Management , Integrated Vulnerability
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/177940 , vital:42892
- Description: In the rapidly changing world of cybersecurity, the constant increase of vulnerabilities continues to be a prevalent issue for many organisations. Malicious actors are aware that most organisations cannot timeously patch known vulnerabilities and are ill-prepared to protect against newly created vulnerabilities where a signature or an available patch has not yet been created. Consequently, information security personnel face ongoing challenges to mitigate these risks. In this research, the problem of remediation in a world of increasing vulnerabilities is considered. The current paradigm of vulnerability and patch management is reviewed using a pragmatic approach to all associated variables of these services / practices and, as a result, what is working and what is not working in terms of remediation is understood. In addition to the analysis, a taxonomy is created to provide a graphical representation of all associated variables to vulnerability and patch management based on existing literature. Frameworks currently being utilised in the industry to create an effective engagement model between vulnerability and patch management services are considered. The link between quantifying a threat, vulnerability and consequence; what Microsoft has available for patching; and the action plan for resulting vulnerabilities is explored. Furthermore, the processes and means of communication between each of these services are investigated to ensure there is effective remediation of vulnerabilities, ultimately improving the security risk posture of an organisation. In order to effectively measure the security risk posture, progress is measured between each of these services through a single averaged measurement metric. The outcome of the research highlights influencing factors that impact successful vulnerability management, in line with identified themes from the research taxonomy. These influencing factors are however significantly undermined due to resources within the same organisations not having a clear and consistent understanding of their role, organisational capabilities and objectives for effective vulnerability and patch management within their organisations. , Thesis (MSc) -- Faculty of Science, Computer Science, 2021
- Full Text:
- Authors: Carstens, Duane
- Date: 2021-04
- Subjects: Computer security , Computer security -- Management , Computer networks -- Security measures , Patch Management , Integrated Vulnerability
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/177940 , vital:42892
- Description: In the rapidly changing world of cybersecurity, the constant increase of vulnerabilities continues to be a prevalent issue for many organisations. Malicious actors are aware that most organisations cannot timeously patch known vulnerabilities and are ill-prepared to protect against newly created vulnerabilities where a signature or an available patch has not yet been created. Consequently, information security personnel face ongoing challenges to mitigate these risks. In this research, the problem of remediation in a world of increasing vulnerabilities is considered. The current paradigm of vulnerability and patch management is reviewed using a pragmatic approach to all associated variables of these services / practices and, as a result, what is working and what is not working in terms of remediation is understood. In addition to the analysis, a taxonomy is created to provide a graphical representation of all associated variables to vulnerability and patch management based on existing literature. Frameworks currently being utilised in the industry to create an effective engagement model between vulnerability and patch management services are considered. The link between quantifying a threat, vulnerability and consequence; what Microsoft has available for patching; and the action plan for resulting vulnerabilities is explored. Furthermore, the processes and means of communication between each of these services are investigated to ensure there is effective remediation of vulnerabilities, ultimately improving the security risk posture of an organisation. In order to effectively measure the security risk posture, progress is measured between each of these services through a single averaged measurement metric. The outcome of the research highlights influencing factors that impact successful vulnerability management, in line with identified themes from the research taxonomy. These influencing factors are however significantly undermined due to resources within the same organisations not having a clear and consistent understanding of their role, organisational capabilities and objectives for effective vulnerability and patch management within their organisations. , Thesis (MSc) -- Faculty of Science, Computer Science, 2021
- Full Text:
An investigation into the current state of web based cryptominers and cryptojacking
- Authors: Len, Robert
- Date: 2021-04
- Subjects: Cryptocurrencies , Malware (Computer software) , Computer networks -- Security measures , Computer networks -- Monitoring , Cryptomining , Coinhive , Cryptojacking
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/178248 , vital:42924
- Description: The aim of this research was to conduct a review of the current state and extent of surreptitious crypto mining software and its prevalence as a means for income generation. Income is generated through the use of a viewer's browser to execute custom JavaScript code to mine cryptocurrencies such as Monero and Bitcoin. The research aimed to measure the prevalence of illicit mining scripts being utilised for “in-browser" cryptojacking while further analysing the ecosystems that support the cryptomining environment. The extent of the research covers aspects such as the content (or type) of the sites hosting malicious “in-browser" cryptomining software as well as the occurrences of currencies utilised in the cryptographic mining and the analysis of cryptographic mining code samples. This research aims to compare the results of previous work with the current state of affairs since the closure of Coinhive in March 2018. Coinhive were at the time the market leader in such web based mining services. Beyond the analysis of the prevalence of cryptomining on the web today, research into the methodologies and techniques used to detect and counteract cryptomining are also conducted. This includes the most recent developments in malicious JavaScript de-obfuscation as well as cryptomining signature creation and detection. Methodologies for heuristic JavaScript behaviour identification and subsequent identification of potential malicious out-liars are also included within the research of the countermeasure analysis. The research revealed that although no longer functional, Coinhive remained as the most prevalent script being used for “in-browser" cryptomining services. While remaining the most prevalent, there was however a significant decline in overall occurrences compared to when coinhive.com was operational. Analysis of the ecosystem hosting \in-browser" mining websites was found to be distributed both geographically as well as in terms of domain categorisations. , Thesis (MSc) -- Faculty of Science, Computer Science, 2021
- Full Text:
- Authors: Len, Robert
- Date: 2021-04
- Subjects: Cryptocurrencies , Malware (Computer software) , Computer networks -- Security measures , Computer networks -- Monitoring , Cryptomining , Coinhive , Cryptojacking
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/178248 , vital:42924
- Description: The aim of this research was to conduct a review of the current state and extent of surreptitious crypto mining software and its prevalence as a means for income generation. Income is generated through the use of a viewer's browser to execute custom JavaScript code to mine cryptocurrencies such as Monero and Bitcoin. The research aimed to measure the prevalence of illicit mining scripts being utilised for “in-browser" cryptojacking while further analysing the ecosystems that support the cryptomining environment. The extent of the research covers aspects such as the content (or type) of the sites hosting malicious “in-browser" cryptomining software as well as the occurrences of currencies utilised in the cryptographic mining and the analysis of cryptographic mining code samples. This research aims to compare the results of previous work with the current state of affairs since the closure of Coinhive in March 2018. Coinhive were at the time the market leader in such web based mining services. Beyond the analysis of the prevalence of cryptomining on the web today, research into the methodologies and techniques used to detect and counteract cryptomining are also conducted. This includes the most recent developments in malicious JavaScript de-obfuscation as well as cryptomining signature creation and detection. Methodologies for heuristic JavaScript behaviour identification and subsequent identification of potential malicious out-liars are also included within the research of the countermeasure analysis. The research revealed that although no longer functional, Coinhive remained as the most prevalent script being used for “in-browser" cryptomining services. While remaining the most prevalent, there was however a significant decline in overall occurrences compared to when coinhive.com was operational. Analysis of the ecosystem hosting \in-browser" mining websites was found to be distributed both geographically as well as in terms of domain categorisations. , Thesis (MSc) -- Faculty of Science, Computer Science, 2021
- Full Text:
An investigation into the role of lesson study in developing teachers’ mathematics content and pedagogical content knowledge
- Authors: Kgothego, Naomi Ntsae
- Date: 2021-04
- Subjects: Mathematics -- Study and teaching (Elementary) -- South Africa -- Bojanala Platinum District Municipality , Pedagogical content knowledge , Lesson planning -- South Africa -- Bojanala Platinum District Municipality , Mathematics teachers -- Training of -- South Africa -- Bojanala Platinum District Municipality , South Africa. Department of Basic Education , Kokusai Kyōryoku Jigyōdan
- Language: English
- Type: thesis , text , Masters , MEd
- Identifier: http://hdl.handle.net/10962/178019 , vital:42899
- Description: Results of international assessments conducted with South African learners, both in primary and secondary schools, suggest that South African learners underperform in mathematics (Spaull, 2013). While there are numerous explanations for this, one of the key explanations is that teachers are deemed to have inadequate knowledge of both mathematics content and pedagogy. Poor content and pedagogical knowledge are indications that teachers are not adequately trained to teach mathematics (Green, 2011). To improve teachers' content and pedagogical knowledge, well-planned and researched professional development programmes need to be put in place. Current professional development opportunities that centre on workshops are not working as they provide little opportunity for teachers to connect the workshop content to the contexts in which they teach. Through a collaboration between the Department of Basic Education (DBE) and Japan International Corporation Agency (JICA), the Lesson Study approach is being introduced to support teachers' professional development. This research seeks to research this approach within the context of Foundation Phase mathematics education. The research asks: How does Lesson Study contribute to the development of teachers' mathematics content and pedagogical content knowledge? Two sub-questions were developed to support the main question: • What mathematics content knowledge do teachers develop as the engage in LS? • What pedagogical content knowledge do teachers develop as they engage in LS? Using a qualitative interpretivist case study approach, I worked collaboratively with four Grade 1 teachers from two schools. Data was generated through observations, semi-structured interviews and document analysis as we engaged in the Lesson Study process. The Mathematics Knowledge for Teaching (Ball, Thames & Phelps, 2008) and the Knowledge Quartet (Rowland, Turner, Thwaites & Huckstep, 2009) frameworks were used as analytic and explanatory tools in this research. This study's findings showed that participation in the interactive cycles of Lesson Study developed the teachers’ confidence, their pedagogical content knowledge and skills and provided them with the opportunity to collaborate and reflect on their knowledge. The study's findings suggest that lesson study can be used as a strategy for improving teacher professional development. , Thesis (MEd) -- Faculty of Education, Education, 2021
- Full Text:
- Authors: Kgothego, Naomi Ntsae
- Date: 2021-04
- Subjects: Mathematics -- Study and teaching (Elementary) -- South Africa -- Bojanala Platinum District Municipality , Pedagogical content knowledge , Lesson planning -- South Africa -- Bojanala Platinum District Municipality , Mathematics teachers -- Training of -- South Africa -- Bojanala Platinum District Municipality , South Africa. Department of Basic Education , Kokusai Kyōryoku Jigyōdan
- Language: English
- Type: thesis , text , Masters , MEd
- Identifier: http://hdl.handle.net/10962/178019 , vital:42899
- Description: Results of international assessments conducted with South African learners, both in primary and secondary schools, suggest that South African learners underperform in mathematics (Spaull, 2013). While there are numerous explanations for this, one of the key explanations is that teachers are deemed to have inadequate knowledge of both mathematics content and pedagogy. Poor content and pedagogical knowledge are indications that teachers are not adequately trained to teach mathematics (Green, 2011). To improve teachers' content and pedagogical knowledge, well-planned and researched professional development programmes need to be put in place. Current professional development opportunities that centre on workshops are not working as they provide little opportunity for teachers to connect the workshop content to the contexts in which they teach. Through a collaboration between the Department of Basic Education (DBE) and Japan International Corporation Agency (JICA), the Lesson Study approach is being introduced to support teachers' professional development. This research seeks to research this approach within the context of Foundation Phase mathematics education. The research asks: How does Lesson Study contribute to the development of teachers' mathematics content and pedagogical content knowledge? Two sub-questions were developed to support the main question: • What mathematics content knowledge do teachers develop as the engage in LS? • What pedagogical content knowledge do teachers develop as they engage in LS? Using a qualitative interpretivist case study approach, I worked collaboratively with four Grade 1 teachers from two schools. Data was generated through observations, semi-structured interviews and document analysis as we engaged in the Lesson Study process. The Mathematics Knowledge for Teaching (Ball, Thames & Phelps, 2008) and the Knowledge Quartet (Rowland, Turner, Thwaites & Huckstep, 2009) frameworks were used as analytic and explanatory tools in this research. This study's findings showed that participation in the interactive cycles of Lesson Study developed the teachers’ confidence, their pedagogical content knowledge and skills and provided them with the opportunity to collaborate and reflect on their knowledge. The study's findings suggest that lesson study can be used as a strategy for improving teacher professional development. , Thesis (MEd) -- Faculty of Education, Education, 2021
- Full Text:
An investigation of support services available for black female owners of bed & breakfasts in Makhanda
- Authors: Mdluli, Lukhona Silubonile
- Date: 2021-04
- Subjects: Bed and breakfast accommodations -- South Africa -- Makhanda , Businesspeople, Black -- South Africa -- Makhanda , Business enterprises, Black -- South Africa -- Makhanda , Women-owned business enterprises -- South Africa -- Makhanda , Government aid to small business -- South Africa , Small business -- South Africa -- Makhanda , Racism -- South Africa -- Makhanda , Businesswomen -- South Africa -- Makhanda
- Language: English
- Type: thesis , text , Masters , MBA
- Identifier: http://hdl.handle.net/10962/177181 , vital:42797
- Description: Over the last 26 years, the South African government has committed to SMME development. To do this, policies and support institutions were put in place which would create a favourable environment for SMME development. This was particularly important as after 1994, when the South African economy was re-integrated into global markets after years of having sanctions imposed against the country as a result of the apartheid system. The tourism industry was identified as one of the key economic drivers which would strengthen the economy and assist in job creation, especially since South Africa would be able to attract international tourists. Further, it created the opportunity for new participants to enter the industry, including black entrepreneurs who previously could not enter the industry as a result of the apartheid laws. The opening up of the country to international markets and the focus on the tourism industry also presented the opportunity for new forms of tourism to be explored including township tourism, which gave rise to the black-owned bed & breakfast sector. Over time, it has become evident that black entrepreneurs in this sector are facing a number of challenges, in spite of the pro-SMME policies and support institutions that are in place. Because this study seeks to investigate the support services available for black female bed & breakfast owners in Makhanda, a qualitative research approach using the interpretative theoretical framework was applied. By using semi-structured interview questions, to establish what challenges do black female bed and breakfast owners face the researcher was able to respond to the following; what participants identify as their needs; and whether they are able to access the support services that are made available by the Government. Results indicated that the majority of entrepreneurs have difficulty accessing funding to develop their businesses. The seasonality of Grahamstown/ Makhanda tourism businesses has its pros and cons for tourism entrepreneurs. Despite efforts by government to transform the tourism industry, black female entrepreneurs in this industry still experience a myriad of challenges, including passive racism. Insufficient institutional support and inaccessible support services for women have made it difficult to manage in this this environment. Thus, a recommendation is put forward for female focused entrepreneurship policy, which is more responsive in terms of a judicial and legal system(s) aimed at addressing women’s particular needs and challenges. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2021
- Full Text:
- Authors: Mdluli, Lukhona Silubonile
- Date: 2021-04
- Subjects: Bed and breakfast accommodations -- South Africa -- Makhanda , Businesspeople, Black -- South Africa -- Makhanda , Business enterprises, Black -- South Africa -- Makhanda , Women-owned business enterprises -- South Africa -- Makhanda , Government aid to small business -- South Africa , Small business -- South Africa -- Makhanda , Racism -- South Africa -- Makhanda , Businesswomen -- South Africa -- Makhanda
- Language: English
- Type: thesis , text , Masters , MBA
- Identifier: http://hdl.handle.net/10962/177181 , vital:42797
- Description: Over the last 26 years, the South African government has committed to SMME development. To do this, policies and support institutions were put in place which would create a favourable environment for SMME development. This was particularly important as after 1994, when the South African economy was re-integrated into global markets after years of having sanctions imposed against the country as a result of the apartheid system. The tourism industry was identified as one of the key economic drivers which would strengthen the economy and assist in job creation, especially since South Africa would be able to attract international tourists. Further, it created the opportunity for new participants to enter the industry, including black entrepreneurs who previously could not enter the industry as a result of the apartheid laws. The opening up of the country to international markets and the focus on the tourism industry also presented the opportunity for new forms of tourism to be explored including township tourism, which gave rise to the black-owned bed & breakfast sector. Over time, it has become evident that black entrepreneurs in this sector are facing a number of challenges, in spite of the pro-SMME policies and support institutions that are in place. Because this study seeks to investigate the support services available for black female bed & breakfast owners in Makhanda, a qualitative research approach using the interpretative theoretical framework was applied. By using semi-structured interview questions, to establish what challenges do black female bed and breakfast owners face the researcher was able to respond to the following; what participants identify as their needs; and whether they are able to access the support services that are made available by the Government. Results indicated that the majority of entrepreneurs have difficulty accessing funding to develop their businesses. The seasonality of Grahamstown/ Makhanda tourism businesses has its pros and cons for tourism entrepreneurs. Despite efforts by government to transform the tourism industry, black female entrepreneurs in this industry still experience a myriad of challenges, including passive racism. Insufficient institutional support and inaccessible support services for women have made it difficult to manage in this this environment. Thus, a recommendation is put forward for female focused entrepreneurship policy, which is more responsive in terms of a judicial and legal system(s) aimed at addressing women’s particular needs and challenges. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2021
- Full Text:
Anisotropic copper oxide nanorods decorated with gold and palladium nanoparticles and their enzymatic properties
- Authors: Sicwetsha, Simbongile
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/178547 , vital:42949
- Description: Access restricted until April 2023. , Thesis (MSc) -- Faculty of Science, Chemistry, 2021
- Full Text:
- Authors: Sicwetsha, Simbongile
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/178547 , vital:42949
- Description: Access restricted until April 2023. , Thesis (MSc) -- Faculty of Science, Chemistry, 2021
- Full Text:
Baculovirus synergism for improved management of false codling moth Thaumatotibia leucotreta Meyr. (Lepidoptera: Tortricidae)
- Authors: Taylor, David Graham
- Date: 2021-04
- Subjects: Baculoviruses , Cryptophlebia leucotreta , Cryptophlebia leucotreta -- Biological control , Biological pest control agents , Citrus -- Diseases and pests , Codling moth , Cryptophlebia peltastica nucleopolyhedrovirus (CrpeNPV)
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/176942 , vital:42774
- Description: Baculoviruses are an environmentally friendly and effective agent for managing lepidopteran pests. This includes the management of Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), a serious pest of citrus in Southern Africa and a major threat to the South African citrus export industry. For more than 15 years, CrleGV-SA- based biopesticides have been used as part of an integrated pest management strategy for the control of T. leucotreta in citrus orchards in South Africa, under the names Cryptogran™ and Cryptex®. While these biopesticides have been effective during this period, there are some areas in which baculovirus use could potentially be improved. Baculoviruses are notoriously slow to kill in comparison to chemical-based pesticides, and lately, pest resistance to baculoviruses has become a major concern with the development of resistance by Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae) to its granulovirus occurring in the field in Europe. The consistent use of CrleGV-SA for more than 15 years in the field has raised concern that T. leucotreta could develop resistance to this virus, and has made it necessary to alter baculovirus-based management strategies to prevent this from occurring. A second baculovirus, Cryptophlebia peltastica nucleopolyhedrovirus (CrpeNPV), has recently been isolated and was shown to be effective against T. leucotreta. However, the interactions between CrleGV-SA and CrpeNPV are not yet understood and so it is important to test these interactions before both viruses are applied on the same orchards. Not only is it important to know whether these viruses could negatively impact each other, but it is also important to test whether they could interact synergistically. A synergistic interaction could not only provide a potential tool for the management of resistance, but it could also be exploited to improve baculovirus-based management of T. leucotreta. In this study, a stock of CrleGV-SA was purified by glycerol gradient centrifugation from T. leucotreta cadavers, while a stock of CrpeNPV purified from Cryptophlebia peltastica (Meyrick) (Lepidoptera: Tortricidae) cadavers was provided by River Bioscience (Pty) Ltd. These stocks were screened for purity by a multiplex polymerase chain reaction (mPCR) protocol designed to detect CrleGV-SA and CrpeNPV. The occlusion body (OB) density was then calculated using darkfield microscopy and a counting chamber. Both stocks were shown to be pure within the limits of the mPCR protocol, and the CrleGV-SA and CrpeNPV stocks were calculated to contain 3.08 × 1011 OBs/mL and 1.92 × 1011 OBs/mL respectively The first aspect of the interaction between CrleGV-SA and CrpeNPV that was investigated was the dose mortality, in terms of lethal concentration. This was calculated using 7-day surface-dose biological assays for each virus and a 1:1 mixture of OBs of the two against T. leucotreta neonates. The lethal concentrations of each treatment required to kill 50 % of larvae (LC50) and 90 % of larvae (LC90) for each treatment were then calculated and compared using a probit regression. The mixed infection performed significantly better than either virus by itself, while each virus by itself did not differ significantly from the other. The LC50 for CrleGV-SA, CrpeNPV and the mixed infection were 1.53 × 104 OBs/mL, 1.15 × 104 OBs/mL and 4.38 × 103 OBs/mL respectively. The LC90 of CrleGV-SA, CrpeNPV and the mixed infection were calculated to be 4.10 × 105 OBs/mL, 1.05 × 105 OBs/mL, and 4.09 × 104 OBs/mL respectively. The second aspect of the interaction between CrleGV-SA and CrpeNPV that was investigated was the speed of kill. A time-response biological assay protocol was created that allowed for effective observation of the larvae. This was then used to generate time-mortality data that were analysed by a logit regression function to calculate and compare the treatments at the time of 50 % larval mortality (LT50) and the time of 90 % mortality (LT90). Each virus by itself did not differ significantly from the other, while the mixed infection took significantly longer to kill 50 % and 90 % of the larvae, suggesting that there is competition for resources between viruses during the secondary, systemic phase of infection. The LT50 for CrleGV-SA, CrpeNPV and the mixed infection were 117.5 hours, 113.5 hours and 139.0 hours respectively. The LT90 for CrleGV-SA, CrpeNPV and the mixed infection were 153.2 hours, 159.3, and 193.4 hours respectively. Finally, the composition of OBs recovered from the cadavers produced by the time-response biological assays were investigated by mPCR. A method for extracting gDNA from OBs in neonate-sized T. leucotreta larvae is described. The presence of CrpeNPV along with CrleGV-SA was noted in 4 out of 9 larvae inoculated with only CrleGV-SA. The presence of CrleGV-SA as well as CrpeNPV was noted in all but one larva inoculated with only CrpeNPV, and both CrleGV-SA and CrpeNPV were noted in all but one larva inoculated with a 1:1 mixture of the two, with one larva only being positive for CrleGV-SA. This suggests either stock contamination or the presence of covert infections of CrleGV-SA and CrpeNPV in the T. leucotreta population used in this study. This is the second study to report an improved lethal concentration of a mixed infection of CrleGV-SA and CrpeNPV against T. leucotreta neonates, and the first study to report the slower speed of kill of a mixed infection of CrleGV-SA and CrpeNPV against T. leucotreta neonates. While the improved lethal concentration of the mixed infection is a promising step in the future improvement of baculovirus-based biopesticides, it is at the cost of a slower speed of kill. , Thesis (MSc) -- Faculty of Science, Department of Zoology and Entomology, 2021
- Full Text:
- Authors: Taylor, David Graham
- Date: 2021-04
- Subjects: Baculoviruses , Cryptophlebia leucotreta , Cryptophlebia leucotreta -- Biological control , Biological pest control agents , Citrus -- Diseases and pests , Codling moth , Cryptophlebia peltastica nucleopolyhedrovirus (CrpeNPV)
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/176942 , vital:42774
- Description: Baculoviruses are an environmentally friendly and effective agent for managing lepidopteran pests. This includes the management of Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), a serious pest of citrus in Southern Africa and a major threat to the South African citrus export industry. For more than 15 years, CrleGV-SA- based biopesticides have been used as part of an integrated pest management strategy for the control of T. leucotreta in citrus orchards in South Africa, under the names Cryptogran™ and Cryptex®. While these biopesticides have been effective during this period, there are some areas in which baculovirus use could potentially be improved. Baculoviruses are notoriously slow to kill in comparison to chemical-based pesticides, and lately, pest resistance to baculoviruses has become a major concern with the development of resistance by Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae) to its granulovirus occurring in the field in Europe. The consistent use of CrleGV-SA for more than 15 years in the field has raised concern that T. leucotreta could develop resistance to this virus, and has made it necessary to alter baculovirus-based management strategies to prevent this from occurring. A second baculovirus, Cryptophlebia peltastica nucleopolyhedrovirus (CrpeNPV), has recently been isolated and was shown to be effective against T. leucotreta. However, the interactions between CrleGV-SA and CrpeNPV are not yet understood and so it is important to test these interactions before both viruses are applied on the same orchards. Not only is it important to know whether these viruses could negatively impact each other, but it is also important to test whether they could interact synergistically. A synergistic interaction could not only provide a potential tool for the management of resistance, but it could also be exploited to improve baculovirus-based management of T. leucotreta. In this study, a stock of CrleGV-SA was purified by glycerol gradient centrifugation from T. leucotreta cadavers, while a stock of CrpeNPV purified from Cryptophlebia peltastica (Meyrick) (Lepidoptera: Tortricidae) cadavers was provided by River Bioscience (Pty) Ltd. These stocks were screened for purity by a multiplex polymerase chain reaction (mPCR) protocol designed to detect CrleGV-SA and CrpeNPV. The occlusion body (OB) density was then calculated using darkfield microscopy and a counting chamber. Both stocks were shown to be pure within the limits of the mPCR protocol, and the CrleGV-SA and CrpeNPV stocks were calculated to contain 3.08 × 1011 OBs/mL and 1.92 × 1011 OBs/mL respectively The first aspect of the interaction between CrleGV-SA and CrpeNPV that was investigated was the dose mortality, in terms of lethal concentration. This was calculated using 7-day surface-dose biological assays for each virus and a 1:1 mixture of OBs of the two against T. leucotreta neonates. The lethal concentrations of each treatment required to kill 50 % of larvae (LC50) and 90 % of larvae (LC90) for each treatment were then calculated and compared using a probit regression. The mixed infection performed significantly better than either virus by itself, while each virus by itself did not differ significantly from the other. The LC50 for CrleGV-SA, CrpeNPV and the mixed infection were 1.53 × 104 OBs/mL, 1.15 × 104 OBs/mL and 4.38 × 103 OBs/mL respectively. The LC90 of CrleGV-SA, CrpeNPV and the mixed infection were calculated to be 4.10 × 105 OBs/mL, 1.05 × 105 OBs/mL, and 4.09 × 104 OBs/mL respectively. The second aspect of the interaction between CrleGV-SA and CrpeNPV that was investigated was the speed of kill. A time-response biological assay protocol was created that allowed for effective observation of the larvae. This was then used to generate time-mortality data that were analysed by a logit regression function to calculate and compare the treatments at the time of 50 % larval mortality (LT50) and the time of 90 % mortality (LT90). Each virus by itself did not differ significantly from the other, while the mixed infection took significantly longer to kill 50 % and 90 % of the larvae, suggesting that there is competition for resources between viruses during the secondary, systemic phase of infection. The LT50 for CrleGV-SA, CrpeNPV and the mixed infection were 117.5 hours, 113.5 hours and 139.0 hours respectively. The LT90 for CrleGV-SA, CrpeNPV and the mixed infection were 153.2 hours, 159.3, and 193.4 hours respectively. Finally, the composition of OBs recovered from the cadavers produced by the time-response biological assays were investigated by mPCR. A method for extracting gDNA from OBs in neonate-sized T. leucotreta larvae is described. The presence of CrpeNPV along with CrleGV-SA was noted in 4 out of 9 larvae inoculated with only CrleGV-SA. The presence of CrleGV-SA as well as CrpeNPV was noted in all but one larva inoculated with only CrpeNPV, and both CrleGV-SA and CrpeNPV were noted in all but one larva inoculated with a 1:1 mixture of the two, with one larva only being positive for CrleGV-SA. This suggests either stock contamination or the presence of covert infections of CrleGV-SA and CrpeNPV in the T. leucotreta population used in this study. This is the second study to report an improved lethal concentration of a mixed infection of CrleGV-SA and CrpeNPV against T. leucotreta neonates, and the first study to report the slower speed of kill of a mixed infection of CrleGV-SA and CrpeNPV against T. leucotreta neonates. While the improved lethal concentration of the mixed infection is a promising step in the future improvement of baculovirus-based biopesticides, it is at the cost of a slower speed of kill. , Thesis (MSc) -- Faculty of Science, Department of Zoology and Entomology, 2021
- Full Text:
Bioethical analysis of selected biomedical issues in South Africa and other countries
- Authors: Rusere, Jean
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/178530 , vital:42948
- Description: Access restricted until April 2023. , Thesis (MPharm) -- Faculty of Pharmacy, Pharmacy, 2021
- Full Text:
- Authors: Rusere, Jean
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/178530 , vital:42948
- Description: Access restricted until April 2023. , Thesis (MPharm) -- Faculty of Pharmacy, Pharmacy, 2021
- Full Text:
Biology, ecology and management of the Keurboom moth, Leto venus Cramer and the leafhopper Molopopterus sp. Jacobi in cultivated Honeybush (Cyclopia spp.)
- Authors: Mushore, Tapiwa Gift
- Date: 2021-04
- Subjects: Legumes , Legumes -- Diseases and pests , Hepialidae , Leafhoppers , Pests -- Biological control , Entomopathogenic fungi , Leafhoppers -- Biological control , Hepialidae -- Biological control , Keurboom moth (Leto venus Cramer) , Molopopterus sp. Jacobi , Honeybush (Cyclopia spp.)
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/177125 , vital:42792
- Description: Honeybush, Cyclopia spp. Vent (Fabaceae), farmers have raised pest concerns following commercial cultivation. The Keurboom moth Leto venus Cramer (Lepidoptera: Hepialidae) and the leafhopper Molopopterus sp. Jacobi (Hemiptera: Cicadellidae), are two of the major pests identified in cultivated Honeybush. Laboratory and field studies were conducted to gain an understanding of the biology of these two pests to inform future pest management solutions. Additionally, entomopathogenic fungi were isolated from Honeybush farms and screened for virulence against Molopopterus sp. as a possible management strategy. This study showed that the L. venus infestation on Honeybush was a product of four fixed effects; stem diameter, species of Cyclopia, Farm location and age of the plants. Cyclopia subternata, had the highest likelihood of infestation. Increase in age of the plants resulted in an increase in the stem diameter and therefore a higher probability of infestation. Stem diameter was also shown to be a significant predictor of infestation likelihood. Infestation severity, determined by the number of larvae per plant, was shown to be influenced by three fixed effects; stem diameter, plant species and Farm location. The results also showed that L. venus prefers to initiate penetration at, or just aboveground level. Laboratory studies showed that the leafhopper Molopopterus sp. undergoes five nymphal instars with an average egg incubation time of 20 days, development time from 1st instar to adult of 26 days and average generation time of 47 days. Laboratory experiments revealed variations in host preference by the leafhopper over a period of 15 days. Cyclopia longifolia was identified to be the most preferred species for feeding compared to the two other commonly cultivated species, C. subternata and C. maculata. The results were consistent with those obtained from the field survey which showed that leafhopper density was influenced by four fixed effects; plant species, age of the plant, Farm location and harvesting practices. There were significant differences in leafhopper density in different species with C. longifolia having the highest number of leafhoppers per plant. There were differences in leafhopper density in different farms as 57% of the sampled farms had leafhopper infestations, of these farms, Lodestone and Kurland had the highest leafhopper densities. Harvested plants were shown to have significantly higher leafhopper density than non-harvested plants. Age was also shown to influence leafhopper density, which reduced with an increase in the age of the plants. A total of 20 fungal isolates were recovered from 98 soil samples of which 70% were from Honeybush fields and 30% were from surrounding refugia. Fusarium oxysporum isolates comprised 20% of the recovered isolates, with Metarhizium anisopliae isolates making up the remainder. Laboratory bioassays against adults and nymphs of the leafhopper, Molopopterus sp., showed that F. oxysporum isolates induced 10 – 45% mortality and M. anisopliae isolates induce 30 – 80% mortality. Metarhizium anisopliae isolates J S1, KF S3, KF S11, KF S13, LS1 and LS2 were the most virulent and induced over 60% mortality in both Molopopterus sp. nymphs and adults. The results of this study showed pest preference towards different Cyclopia species. As such, they should be managed differently. Furthermore, L. venus was observed to occur in low densities, hence, it cannot be considered a major pest. However, Molopopterus sp. recorded high population densities making it a major pest in Honeybush production. Positive results indicated that some of the isolated fungal isolates have potential for control, an avenue worth investigating further. , Thesis (MSc) -- Faculty of Science, Department of Zoology and Entomology, 2021
- Full Text:
- Authors: Mushore, Tapiwa Gift
- Date: 2021-04
- Subjects: Legumes , Legumes -- Diseases and pests , Hepialidae , Leafhoppers , Pests -- Biological control , Entomopathogenic fungi , Leafhoppers -- Biological control , Hepialidae -- Biological control , Keurboom moth (Leto venus Cramer) , Molopopterus sp. Jacobi , Honeybush (Cyclopia spp.)
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/177125 , vital:42792
- Description: Honeybush, Cyclopia spp. Vent (Fabaceae), farmers have raised pest concerns following commercial cultivation. The Keurboom moth Leto venus Cramer (Lepidoptera: Hepialidae) and the leafhopper Molopopterus sp. Jacobi (Hemiptera: Cicadellidae), are two of the major pests identified in cultivated Honeybush. Laboratory and field studies were conducted to gain an understanding of the biology of these two pests to inform future pest management solutions. Additionally, entomopathogenic fungi were isolated from Honeybush farms and screened for virulence against Molopopterus sp. as a possible management strategy. This study showed that the L. venus infestation on Honeybush was a product of four fixed effects; stem diameter, species of Cyclopia, Farm location and age of the plants. Cyclopia subternata, had the highest likelihood of infestation. Increase in age of the plants resulted in an increase in the stem diameter and therefore a higher probability of infestation. Stem diameter was also shown to be a significant predictor of infestation likelihood. Infestation severity, determined by the number of larvae per plant, was shown to be influenced by three fixed effects; stem diameter, plant species and Farm location. The results also showed that L. venus prefers to initiate penetration at, or just aboveground level. Laboratory studies showed that the leafhopper Molopopterus sp. undergoes five nymphal instars with an average egg incubation time of 20 days, development time from 1st instar to adult of 26 days and average generation time of 47 days. Laboratory experiments revealed variations in host preference by the leafhopper over a period of 15 days. Cyclopia longifolia was identified to be the most preferred species for feeding compared to the two other commonly cultivated species, C. subternata and C. maculata. The results were consistent with those obtained from the field survey which showed that leafhopper density was influenced by four fixed effects; plant species, age of the plant, Farm location and harvesting practices. There were significant differences in leafhopper density in different species with C. longifolia having the highest number of leafhoppers per plant. There were differences in leafhopper density in different farms as 57% of the sampled farms had leafhopper infestations, of these farms, Lodestone and Kurland had the highest leafhopper densities. Harvested plants were shown to have significantly higher leafhopper density than non-harvested plants. Age was also shown to influence leafhopper density, which reduced with an increase in the age of the plants. A total of 20 fungal isolates were recovered from 98 soil samples of which 70% were from Honeybush fields and 30% were from surrounding refugia. Fusarium oxysporum isolates comprised 20% of the recovered isolates, with Metarhizium anisopliae isolates making up the remainder. Laboratory bioassays against adults and nymphs of the leafhopper, Molopopterus sp., showed that F. oxysporum isolates induced 10 – 45% mortality and M. anisopliae isolates induce 30 – 80% mortality. Metarhizium anisopliae isolates J S1, KF S3, KF S11, KF S13, LS1 and LS2 were the most virulent and induced over 60% mortality in both Molopopterus sp. nymphs and adults. The results of this study showed pest preference towards different Cyclopia species. As such, they should be managed differently. Furthermore, L. venus was observed to occur in low densities, hence, it cannot be considered a major pest. However, Molopopterus sp. recorded high population densities making it a major pest in Honeybush production. Positive results indicated that some of the isolated fungal isolates have potential for control, an avenue worth investigating further. , Thesis (MSc) -- Faculty of Science, Department of Zoology and Entomology, 2021
- Full Text:
Characterization of the diversity and metabolic potential of hypolithic communities in dronning Maud Land, Antarctica
- Authors: Mikhari, Rito Leanah
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/178490 , vital:42944
- Description: Access restricted until April 2022. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2021
- Full Text:
- Authors: Mikhari, Rito Leanah
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/178490 , vital:42944
- Description: Access restricted until April 2022. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2021
- Full Text:
Cognitive justice and environmental learning in South African social movements
- Authors: Burt, Jane Caroline
- Date: 2021-04
- Subjects: Transformative learning , Water security -- South Africa , Environmental education -- South Africa , EEASA (Organization) , Civil society -- South Africa , Water justice , Cognitive justice
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/174437 , vital:42477 , http://dx.doi.org/10.21504/10962/174437
- Description: This thesis by publication is an applied study into transformative learning as an emancipatory practice for water justice. It is guided by the core research question: How can cognitively just learning be an activist practice in social movements working towards water justice? To address this question, I use the applied critical realist approach which makes use of three moments of moral reasoning which are very similar to the approach adopted in the learning intervention that is the focus of this research. These three moments are: Diagnose, Explain, Act – sometimes known as the DEA model (Bhaskar, 2008, 243; Munnik & Price, 2015). The research object is the Changing Practice course for community-based environmental and social movements. The course was developed and studied over seven years, starting from the reflexive scholarship of environmental learning in South Africa, particularly the adult learning model of working together/working away developed through the Environmental Education Association of Southern Africa in partnership with the Environmental Learning Research Centre at Rhodes University (Lotz-Sisitka & Raven, 2004). We (the facilitators/educators) ran the Changing Practice course three times (2012-2014; 2014-2016; 2016-2018), in which I generated substantive data which forms the empirical base on which this study was developed. We found the concept of cognitive justice (Visvanathan, 2005; de Sousa Santos, 2016) to be a powerful mobilizing concept with which to carry out emancipatory research and learning, in three ways. First, it brought together a group of researchers, activists and practitioners from different organizations to work on how to strengthen the role of civil society in monitoring government water policy and practice (Wilson et al., 2016). Second, within the Changing Practice course itself, it became a principle for guiding learning design and pedagogy as well as a way of engaging in dialogue with the participants around the politics of knowledge, exclusion and inclusion in knowledge production, systems of oppression and multiple knowledges (Wilson et al., 2016; Burt et al., 2018). Thirdly, the participants’ change projects (the applied projects undertaken during the ‘working away’ phase between course modules), allowed participants to draw on different knowledge systems, which they learnt to do in the ‘working together’ modules, and to address cognitive justice concerns linked to environmental justice. The change projects also challenged our learning pedagogy by raising contradictions in the course’s approach to learning that needed to be transformed in order for our pedagogy to be more cognitively just. Throughout this thesis I argue that the work of cognitive justice deepens the connections between people, institutions and structures, particularly in relation to transformative learning. Our intention was to identify and critique structures and ideologies that perpetuated oppressive relations, and then to identify and enact the work needed towards transforming these relations. This is why I often refer to cognitive justice as a solidarity and mobilizing concept, and I use the term cognitive justice praxis to mean the reflection and actions that are needed to enact cognitive just learning. The facilitators and participants of the Changing Practice course worked to remove the layered effects of oppression both in the practice of water justice and in the learning process itself. We worked, however imperfectly, with a caring, collectively-held ethic towards each other and the world. Using the DEA model I applied the critical realist dialectic to analyse contradictions and generate explanations through four articles as reflexive writing projects (See Part 2 of this thesis). I used the critical realist dialectic both to reveal contradictions, investigate how these contradictions have come to be, and to generate alternative explanations and action to absent them. Through this research I identified four essential mechanisms for cognitively just environmental learning: care work, co-learning, reflexivity and an interdisciplinary approach to learning scholarship as learning praxis. The essential elements that made the Changing Practice course so effective were the working together/working away design, the encouraging of participants to make the change project something they were passionate about, and the situating and grounding of the Changing Practice course within a social movement network. We were able to show that for academic scholarship to contribute meaningfully to cognitively just learning praxis, it needs to be collaborative and reflexive, and start from the embodied historical and contextual experience of learning as experienced and understood by participants on the course. This demanded an interdisciplinary approach to work with contradictions in learning practice, one that could take into consideration different knowledges and knowledge practices beyond professional disciplines. Both social movement communities and scholarly communities have valuable knowledge to offer each other. As argued in article one, rather than a lack of knowledge, what more often limits our emancipatory action are factors that prevent us from coming closer together. (Burt et al, 2018) This research revealed that social movement learning towards water justice is multi-level care work, the four levels being: individual psychology, our relations with others, our relations with structures such as our social movements, and our relations with the planet. When such care work attains self- reflexivity, practice-reflexivity, co-learning and collective scholarship, it is able to absent the contradictions that inhibit cognitive justice. This thesis is a record of our attempts to learn how to achieve this.
- Full Text:
- Authors: Burt, Jane Caroline
- Date: 2021-04
- Subjects: Transformative learning , Water security -- South Africa , Environmental education -- South Africa , EEASA (Organization) , Civil society -- South Africa , Water justice , Cognitive justice
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/174437 , vital:42477 , http://dx.doi.org/10.21504/10962/174437
- Description: This thesis by publication is an applied study into transformative learning as an emancipatory practice for water justice. It is guided by the core research question: How can cognitively just learning be an activist practice in social movements working towards water justice? To address this question, I use the applied critical realist approach which makes use of three moments of moral reasoning which are very similar to the approach adopted in the learning intervention that is the focus of this research. These three moments are: Diagnose, Explain, Act – sometimes known as the DEA model (Bhaskar, 2008, 243; Munnik & Price, 2015). The research object is the Changing Practice course for community-based environmental and social movements. The course was developed and studied over seven years, starting from the reflexive scholarship of environmental learning in South Africa, particularly the adult learning model of working together/working away developed through the Environmental Education Association of Southern Africa in partnership with the Environmental Learning Research Centre at Rhodes University (Lotz-Sisitka & Raven, 2004). We (the facilitators/educators) ran the Changing Practice course three times (2012-2014; 2014-2016; 2016-2018), in which I generated substantive data which forms the empirical base on which this study was developed. We found the concept of cognitive justice (Visvanathan, 2005; de Sousa Santos, 2016) to be a powerful mobilizing concept with which to carry out emancipatory research and learning, in three ways. First, it brought together a group of researchers, activists and practitioners from different organizations to work on how to strengthen the role of civil society in monitoring government water policy and practice (Wilson et al., 2016). Second, within the Changing Practice course itself, it became a principle for guiding learning design and pedagogy as well as a way of engaging in dialogue with the participants around the politics of knowledge, exclusion and inclusion in knowledge production, systems of oppression and multiple knowledges (Wilson et al., 2016; Burt et al., 2018). Thirdly, the participants’ change projects (the applied projects undertaken during the ‘working away’ phase between course modules), allowed participants to draw on different knowledge systems, which they learnt to do in the ‘working together’ modules, and to address cognitive justice concerns linked to environmental justice. The change projects also challenged our learning pedagogy by raising contradictions in the course’s approach to learning that needed to be transformed in order for our pedagogy to be more cognitively just. Throughout this thesis I argue that the work of cognitive justice deepens the connections between people, institutions and structures, particularly in relation to transformative learning. Our intention was to identify and critique structures and ideologies that perpetuated oppressive relations, and then to identify and enact the work needed towards transforming these relations. This is why I often refer to cognitive justice as a solidarity and mobilizing concept, and I use the term cognitive justice praxis to mean the reflection and actions that are needed to enact cognitive just learning. The facilitators and participants of the Changing Practice course worked to remove the layered effects of oppression both in the practice of water justice and in the learning process itself. We worked, however imperfectly, with a caring, collectively-held ethic towards each other and the world. Using the DEA model I applied the critical realist dialectic to analyse contradictions and generate explanations through four articles as reflexive writing projects (See Part 2 of this thesis). I used the critical realist dialectic both to reveal contradictions, investigate how these contradictions have come to be, and to generate alternative explanations and action to absent them. Through this research I identified four essential mechanisms for cognitively just environmental learning: care work, co-learning, reflexivity and an interdisciplinary approach to learning scholarship as learning praxis. The essential elements that made the Changing Practice course so effective were the working together/working away design, the encouraging of participants to make the change project something they were passionate about, and the situating and grounding of the Changing Practice course within a social movement network. We were able to show that for academic scholarship to contribute meaningfully to cognitively just learning praxis, it needs to be collaborative and reflexive, and start from the embodied historical and contextual experience of learning as experienced and understood by participants on the course. This demanded an interdisciplinary approach to work with contradictions in learning practice, one that could take into consideration different knowledges and knowledge practices beyond professional disciplines. Both social movement communities and scholarly communities have valuable knowledge to offer each other. As argued in article one, rather than a lack of knowledge, what more often limits our emancipatory action are factors that prevent us from coming closer together. (Burt et al, 2018) This research revealed that social movement learning towards water justice is multi-level care work, the four levels being: individual psychology, our relations with others, our relations with structures such as our social movements, and our relations with the planet. When such care work attains self- reflexivity, practice-reflexivity, co-learning and collective scholarship, it is able to absent the contradictions that inhibit cognitive justice. This thesis is a record of our attempts to learn how to achieve this.
- Full Text:
Conceptualisations and pedagogical practices of academic literacy in Namibian higher education
- Authors: Julius, Lukas Homateni
- Date: 2021-04
- Subjects: Information literacy -- Study and teaching (Higher) -- Namibia , Academic writing -- Study and teaching -- Namibia , Qualitative research -- Methodology , Academic language -- Namibia , Information literacy -- Social aspects
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/177293 , vital:42807 , 10.21504/10962/177293
- Description: The purpose of this study was to investigate academic literacy development lecturers’ conceptualisations of academic literacy and resultant pedagogical practices in academic development courses at three different Higher Education Institutional types in Namibia. The research sites were a Traditional University, a University of Technology and a Comprehensive University. The focus was to understand the extent to which the academics’ conceptions of academic literacy and the resultant pedagogical practices in the academic development courses at these three Higher Education Institutions (HEIs) facilitate epistemological access into students’ chosen fields of study. Bernstein’s Pedagogical theory (1990), Genre theory (1996) and Halliday’s Systemic Functional Linguistics (1978) were used as the study’s theoretical lenses and analytical framework. An interpretative paradigm and a qualitative case study design were employed as the research approach. Semi-structured interviews, classroom observations and documentary evidence were used to generate data. Research findings revealed a common (mis)conception of the nature of academic literacy, the resultant inadequate learning support offered to students in the selected academic literacy development courses, and a clear divorcing of academic literacy interventions from the students’ ‘home’ or mainstream disciplines at the three HEIs. The participants understood academic literacy from an autonomous position as a set of generic skills which could be taught outside of mainstream classes. Moreover, findings revealed that this understanding impacted on the design and assessments of all the academic literacy courses across the three universities under study. The study calls for a context sensitive model through which academic literacy acquisition can be scaffolded to meet the discipline-specific epistemological needs of the students. , Elalakano lyehokololoningomwa lyomapekapeko ndika olyo okukonakona ehumithokomeho lyomikalo dhokulesha nokushanga meilongngo lyopombada (oAcademic Literaci) maaputudhilongi, okukonakona omafatululo giisimanintsa moAcademic Literaci osho wo okutala iizemo yomikalo dhayooloka dhokulonga noku ilonga iilongwa yayooloka miiputudhilo yelongo lyopombada moNamibia. Omapekapeko ngaka oga li ga ningilwa miiputudhilo yomaukwatya ta ga landula; Oshiputudhiilo shopamudhigululwakalo, Oshiputudhilo shopaunongononi, nOshiputudilo shomailongo gaandjakana. Oshintsa shopokati shomapekapeko ngaka osho okuuva ko ondodo yowino osho wo euveko lyoAcademic Literaci maaputudhilongi nonkene euveko nontseyo ndjika tayi longithwa oku eta oshizemo tashi humitha komeho euveko lyopombanda lyaalongwa yomailongo geewino dhayooloka miiputudhilo itatu yelongo lyopombanda; shino otashi kwathele aalongwa yamone ontseyo ndjoka tayi ya kwathele meilongo lyawo. Omapekapeko ngano oga longitha omadhiladhiloukithi (eetheori) ga Bernstein’s Pedagogical theori (1990), Genre theori (1996) na Halliday’s Systemic Functional Linguistics theori (1978), mokufatulula nokundjandjukununa iizemo yomapekapeko. Omodela yokukonakona iizemo yongushu tayi ziilile maakonakonwa, oya tala ekonakono ndika onga oshintsa shopokati, oyo ya longithwa, opo ku monike uuyelele wothaathaa. Omikalo dha longifwa mokukonakona noku gongela uuyelele momapekapeko ngano ongaashi, eenkundathana dhayaali, omatalelo geetundi oshoyo omakonakono giinyanyangidhwa tayi kwandjangele nepekapeko ndika. Iizedjemo yepekapeko ndika otayi ulike kutya opena engwangwano montseyo nenge mefatululo lyuukwatya woAcademic Literaci, shoka sha eta enkundipalo meyambidhidho hali pewa aalongwa miilongwa yeewino dhayooloka. Shika otashi ulike kutya kapena etsokumwe pokati keenkambadhala tadhi ningwa kaapudhilongi dhokulonga oAcademic Litraci miilongwa ya yooloka mbyoka tayi ilongelwa kaalongwa miiputudhilo itatu yopombada. iizemmo yepekapeko olyo tuu mdika oya ulike wo kutya aalongwa mboka yaza komailongo ga yooloka oha yi ilongo nuudhigu opo ya pondole ondondo yomadhiladhilo gopombanda meilongo lyuukumwe. Mokukonakona euveko lyoAcademic Literaci, epekapeko ndika olya ndhindhilike kutya aakuthimbinga oyena euveko lyankundipala lyoterma ‘Academic Literaci,’ ano ya nyengwa okukwatakanitha oohedi dhopetameko ndhoka dhina oku ilongwa meikalekelo - ano pondje yiilongwa ikwao. Oshikwao, iizemo oya ulike kutya euveko ndika otali nwetha mo etungepo lyoAcademic Literaci onga oshilongwa, osho wo omakonakono gasho miiputudilo yombombanda itatu yakwatelwa momapekapeko. Hugunina, epekapeko ndika otali ulike/gandja oshiholelwa shomodela ndjoka oAcademic literacy tai vulu okulongwa opo yi kwatelemo eilongo lyiikwatelela kiilongwa osho yo komaitaalo nokeempumbwe dhaalongwa miiputudhilo yopombabda. , Thesis (PhD) -- Faculty of Education, Centre for Higher Education Research, Teaching and Learning (CHERTL), 2021
- Full Text:
- Authors: Julius, Lukas Homateni
- Date: 2021-04
- Subjects: Information literacy -- Study and teaching (Higher) -- Namibia , Academic writing -- Study and teaching -- Namibia , Qualitative research -- Methodology , Academic language -- Namibia , Information literacy -- Social aspects
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/177293 , vital:42807 , 10.21504/10962/177293
- Description: The purpose of this study was to investigate academic literacy development lecturers’ conceptualisations of academic literacy and resultant pedagogical practices in academic development courses at three different Higher Education Institutional types in Namibia. The research sites were a Traditional University, a University of Technology and a Comprehensive University. The focus was to understand the extent to which the academics’ conceptions of academic literacy and the resultant pedagogical practices in the academic development courses at these three Higher Education Institutions (HEIs) facilitate epistemological access into students’ chosen fields of study. Bernstein’s Pedagogical theory (1990), Genre theory (1996) and Halliday’s Systemic Functional Linguistics (1978) were used as the study’s theoretical lenses and analytical framework. An interpretative paradigm and a qualitative case study design were employed as the research approach. Semi-structured interviews, classroom observations and documentary evidence were used to generate data. Research findings revealed a common (mis)conception of the nature of academic literacy, the resultant inadequate learning support offered to students in the selected academic literacy development courses, and a clear divorcing of academic literacy interventions from the students’ ‘home’ or mainstream disciplines at the three HEIs. The participants understood academic literacy from an autonomous position as a set of generic skills which could be taught outside of mainstream classes. Moreover, findings revealed that this understanding impacted on the design and assessments of all the academic literacy courses across the three universities under study. The study calls for a context sensitive model through which academic literacy acquisition can be scaffolded to meet the discipline-specific epistemological needs of the students. , Elalakano lyehokololoningomwa lyomapekapeko ndika olyo okukonakona ehumithokomeho lyomikalo dhokulesha nokushanga meilongngo lyopombada (oAcademic Literaci) maaputudhilongi, okukonakona omafatululo giisimanintsa moAcademic Literaci osho wo okutala iizemo yomikalo dhayooloka dhokulonga noku ilonga iilongwa yayooloka miiputudhilo yelongo lyopombada moNamibia. Omapekapeko ngaka oga li ga ningilwa miiputudhilo yomaukwatya ta ga landula; Oshiputudhiilo shopamudhigululwakalo, Oshiputudhilo shopaunongononi, nOshiputudilo shomailongo gaandjakana. Oshintsa shopokati shomapekapeko ngaka osho okuuva ko ondodo yowino osho wo euveko lyoAcademic Literaci maaputudhilongi nonkene euveko nontseyo ndjika tayi longithwa oku eta oshizemo tashi humitha komeho euveko lyopombanda lyaalongwa yomailongo geewino dhayooloka miiputudhilo itatu yelongo lyopombanda; shino otashi kwathele aalongwa yamone ontseyo ndjoka tayi ya kwathele meilongo lyawo. Omapekapeko ngano oga longitha omadhiladhiloukithi (eetheori) ga Bernstein’s Pedagogical theori (1990), Genre theori (1996) na Halliday’s Systemic Functional Linguistics theori (1978), mokufatulula nokundjandjukununa iizemo yomapekapeko. Omodela yokukonakona iizemo yongushu tayi ziilile maakonakonwa, oya tala ekonakono ndika onga oshintsa shopokati, oyo ya longithwa, opo ku monike uuyelele wothaathaa. Omikalo dha longifwa mokukonakona noku gongela uuyelele momapekapeko ngano ongaashi, eenkundathana dhayaali, omatalelo geetundi oshoyo omakonakono giinyanyangidhwa tayi kwandjangele nepekapeko ndika. Iizedjemo yepekapeko ndika otayi ulike kutya opena engwangwano montseyo nenge mefatululo lyuukwatya woAcademic Literaci, shoka sha eta enkundipalo meyambidhidho hali pewa aalongwa miilongwa yeewino dhayooloka. Shika otashi ulike kutya kapena etsokumwe pokati keenkambadhala tadhi ningwa kaapudhilongi dhokulonga oAcademic Litraci miilongwa ya yooloka mbyoka tayi ilongelwa kaalongwa miiputudhilo itatu yopombada. iizemmo yepekapeko olyo tuu mdika oya ulike wo kutya aalongwa mboka yaza komailongo ga yooloka oha yi ilongo nuudhigu opo ya pondole ondondo yomadhiladhilo gopombanda meilongo lyuukumwe. Mokukonakona euveko lyoAcademic Literaci, epekapeko ndika olya ndhindhilike kutya aakuthimbinga oyena euveko lyankundipala lyoterma ‘Academic Literaci,’ ano ya nyengwa okukwatakanitha oohedi dhopetameko ndhoka dhina oku ilongwa meikalekelo - ano pondje yiilongwa ikwao. Oshikwao, iizemo oya ulike kutya euveko ndika otali nwetha mo etungepo lyoAcademic Literaci onga oshilongwa, osho wo omakonakono gasho miiputudilo yombombanda itatu yakwatelwa momapekapeko. Hugunina, epekapeko ndika otali ulike/gandja oshiholelwa shomodela ndjoka oAcademic literacy tai vulu okulongwa opo yi kwatelemo eilongo lyiikwatelela kiilongwa osho yo komaitaalo nokeempumbwe dhaalongwa miiputudhilo yopombabda. , Thesis (PhD) -- Faculty of Education, Centre for Higher Education Research, Teaching and Learning (CHERTL), 2021
- Full Text:
Constraining simulation uncertainties in a hydrological model of the Congo River Basin including a combined modelling approach for channel-wetland exchanges
- Authors: Kabuya, Pierre Mulamba
- Date: 2021-04
- Subjects: Congo River Watershed , Watersheds -- Congo (Democratic Republic) , Hydrologic models , Rain and rainfall -- Mathematical models , Runoff -- Mathematical models , Wetland hydrology
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/177997 , vital:42897 , 10.21504/10962/177997
- Description: Compared to other large river basins of the world, such as the Amazon, the Congo River Basin appears to be the most ungauged and less studied. This is partly because the basin lacks sufficient observational hydro-climatic monitoring stations and appropriate information on physiographic basin properties at a spatial scale deemed for hydrological applications, making it difficult to estimate water resources at the scale of sub-basins (Chapter 3). In the same time, the basin is facing the challenges related to rapid population growth, uncontrolled urbanisation as well as climate change. Adequate quantification of hydrological processes across different spatial and temporal scales in the basin, and the drivers of change, is essential for prediction and strategic planning to ensure sustainable management of water resources in the Congo River Basin. Hydrological models are particularly important to generate the required information. However, the shortness of the available streamflow records, lack of spatial representativeness of the available streamflow gauging stations and the lack of understanding of the processes in channel-wetland exchanges, are the main challenges that constrain the use of traditional approaches to models development. They also contribute to increased uncertainty in the estimation of water resources across the basin (Chapter 1 and 2). Given this ungauged nature of the Congo River Basin, it is important to resort to hydrological modelling approaches that can reasonably quantify and model the uncertainty associated with water resources estimation (Chapter 4) to make hydrological predictions reliable. This study explores appropriate methods for hydrological predictions and water resources assessment in ungauged catchments of the Congo River Basin. In this context, the core modelling framework combines the quantification of uncertainty in constraint indices, hydrological modelling and hydrodynamic modelling. The latter accounts for channel-wetland exchanges in sub-basins where wetlands exert considerable influence on downstream flow regimes at the monthly time scale. The constraint indices are the characteristics of a sub-basin’s long-term hydrological behaviour and may reflect the dynamics of the different components of the catchment water balance such as climate, water storage and different runoff processes. Currently, six constraint indices namely the mean monthly runoff volume (MMQ in m3 *106), mean monthly groundwater recharge depth (MMR in mm), the 10th, 50th and 90th percentiles of the flow duration curve expressed as a fraction of MMQ (Q10/MMQ, Q50/MMQ, Q90/MMQ) and the percentage of time that zero flows are expected (%Zero), are used in the modelling approach. These were judged to be the minimum number of key indices that can discriminate between different hydrological responses. The constraint indices in the framework help to determine an uncertainty range within which behavioural model parameters of the expected hydrological response can be identified. Predictive equations of the constraint indices across all climate and physiographic regions of the Congo Basin were based only on the aridity index because it was the most influential sub-basin attribute (Chapter 5) for which quantitative information was available. The degree of uncertainty in the constraint Q10/MMQ and Q50/MMQ indices is less than 41%, while it is somewhat higher for the mean monthly runoff (MMQ) and Q90/MMQ constraint indices. The established uncertainty ranges of the constraint indices were tested in some selected sub-basins of the Congo Basin, including the Lualaba (93 sub-basins), Sangha (24 sub-basins), Oubangui (19 sub-basins), Batéké plateaux (4 sub-basins), Kasai (4 sub-basins) and Inkisi (3 sub-basins). The results proved useful through the application of a 2-stage uncertainty approach of the PITMAN model. However, it comes out of this study that the application of the original constraint indices ranges (Chapter 5) generated satisfactory simulation results in some areas, while in others both small and large adjustments were required to fully capture some aspects of the observed hydrological responses (Chapter 6). Part of the reason is attributed to the availability and quality of streamflow data used to develop the constraint indices ranges (Chapter 5). The main issue identified in the modelling process was whether the changes made to the original constraints at headwater-gauged sub-basins can be applied to ungauged upstream sub-basins to match the observed flow at downstream gauging stations. Ideally, only gauged sub-basin’s constraints can be easily revised based on the observed flow. However, the refinement made to gauged sub-basins alone may fail to substantially affect the results if ungauged upstream sub-basins exert a major impact on defining downstream hydrological response. The majority of gauging stations used in this analysis are located downstream of many upstream ungauged sub-basins and therefore adjustments were required in ungauged sub-basins. These adjustments consist of shifting the full range of a constraint index either towards higher or lower values, depending on the degree to which the simulated uncertainty bounds depart from the observed flow. While this modelling approach seems effective in capturing many aspects of the hydrological responses with a reduced level of uncertainty compared to a previous study, it is recommended that the approach be extended to the remaining parts of the Congo Basin and assessed under current and future development conditions including environmental changes. A 2D hydrodynamic river-wetland model (LISFLOOD-FP) has been used to explicitly represent the inundation process exchanges between river channels and wetland systems. The hydrodynamic modelling outputs are used to calibrate the PITMAN wetland sub-model parameters. The five hydrodynamic models constructed for Ankoro, Kamalondo, Kundelungu, Mweru and Tshiangalele wetland systems have been partially validated using independent estimates of inundation extents available from Landsat imagery. Other sources of data such as remote sensing of water level altimetry, SAR images and wetland storage estimates may be used to improve the validation results. However, the important objective in this study was to make sure that flow volume exchanges between river channels and their adjacent floodplains were being simulated realistically. The wetland sub-model parameters are calibrated in a spreadsheet version of the PITMAN wetland routine to achieve visual correspondence between the LISFLOOD-FP and PITMAN wetland sub-model outputs (Storage volumes and channel outputs). The hysteretic patterns of the river-wetland processes were quantified using hysteresis indices and were associated with the spill and return flow parameters of the wetland sub-model and eventually with the wetland morphometric characteristics. One example is the scale parameter of the return flow function (AA), which shows a good relationship with the average surface slope of the wetland when the coefficient parameter (BB) of the same function is kept constant to a value of 1.25. The same parameter (AA) is a good indicator of the wetland emptying mechanism. A small AA indicates a wetland that slowly releases its flow, resulting in a highly delayed and attenuated hydrological response in downstream sub-basins. This understanding has a practical advantage for the estimation of the PITMAN wetland parameters in the many areas where it is not possible, or where the resources are not available, to run complex hydrodynamic models (Chapter 7). The inclusion of these LISFLOOD-FP informed wetland parameters in the basin-scale hydrological modelling results in acceptable simulations for the lower Lualaba drainage system. The small wetlands, like Ankoro and Tshiangalele, have a negligible impact on downstream flow regimes, whereas large wetlands, such as Kamalondo and Mweru, have very large impacts. In general, the testing of the original constraint indices in the region of wetlands and further downstream of the Lualaba drainage system has shown acceptable results. However, there remains an unresolved uncertainty issue related to the under and over-estimation of some aspects of the hydrological response at both Mulongo and Ankoro, two gauging stations in the immediate downstream of the Kamalondo wetland system. It is difficult to attribute this uncertainty to Kamalondo wetland parameters alone because many of the incremental sub-basins contributing to wetland inflows are ungauged. The issue at Mulongo is the under simulation of low flow, while the high flows at the Ankoro gauging station are over-simulated. However, the pattern of the calibrated constraint indices in this region (Chapter 8) shows that the under simulation of low flow at Mulongo cannot be attributed to incremental sub-basins (between Bukama, Kapolowe and Mulongo gauging stations), because their Q90/MMQ constraint indices are even slightly above the original constraint ranges, but maintain a spatial consistency with sub-basins of other regions. Similarly, sub-basins located between Mulongo, Luvua and Ankoro gauging stations have high flow indices slightly below the original constraint ranges and therefore they are unlikely to be responsible for the over simulation of high flow at the Ankoro gauging station. These facts highlight the need for a further understanding of the complex wetland system of Kamalondo. Short-term data collection and monitoring programme are required. Important tributaries that drain to this wetland need to be monitored by installing water level loggers and periodically collecting flow data and river bathymetry. This programme should lead to the development of rating curves of wetland input tributaries. This would partially solve the unresolved uncertainty issues at the Ankoro and Mulongo gauging stations. The integrated modelling approach offers many opportunities in the Congo Basin. The quantified and modelled uncertainty helps to identify regions with high uncertainty and allows for the identification of various data collection and management strategies that can potentially contribute to the uncertainty reduction. The quantified channel-wetland exchanges contribute to the improvement of the overall knowledge of water resources estimation within the regions where the effects of wetlands are evident even at the monthly time scale. In contrast, ignoring uncertainty in the estimates of water resources availability means that water resources planning and management decisions in the Congo Basin will continue to be based on inadequate information and unquantified uncertainty, thus increasing the risk associated with water resources decision making. , Thesis (PhD) -- Faculty of Science, Institute for Water Research, 2021
- Full Text:
- Authors: Kabuya, Pierre Mulamba
- Date: 2021-04
- Subjects: Congo River Watershed , Watersheds -- Congo (Democratic Republic) , Hydrologic models , Rain and rainfall -- Mathematical models , Runoff -- Mathematical models , Wetland hydrology
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/177997 , vital:42897 , 10.21504/10962/177997
- Description: Compared to other large river basins of the world, such as the Amazon, the Congo River Basin appears to be the most ungauged and less studied. This is partly because the basin lacks sufficient observational hydro-climatic monitoring stations and appropriate information on physiographic basin properties at a spatial scale deemed for hydrological applications, making it difficult to estimate water resources at the scale of sub-basins (Chapter 3). In the same time, the basin is facing the challenges related to rapid population growth, uncontrolled urbanisation as well as climate change. Adequate quantification of hydrological processes across different spatial and temporal scales in the basin, and the drivers of change, is essential for prediction and strategic planning to ensure sustainable management of water resources in the Congo River Basin. Hydrological models are particularly important to generate the required information. However, the shortness of the available streamflow records, lack of spatial representativeness of the available streamflow gauging stations and the lack of understanding of the processes in channel-wetland exchanges, are the main challenges that constrain the use of traditional approaches to models development. They also contribute to increased uncertainty in the estimation of water resources across the basin (Chapter 1 and 2). Given this ungauged nature of the Congo River Basin, it is important to resort to hydrological modelling approaches that can reasonably quantify and model the uncertainty associated with water resources estimation (Chapter 4) to make hydrological predictions reliable. This study explores appropriate methods for hydrological predictions and water resources assessment in ungauged catchments of the Congo River Basin. In this context, the core modelling framework combines the quantification of uncertainty in constraint indices, hydrological modelling and hydrodynamic modelling. The latter accounts for channel-wetland exchanges in sub-basins where wetlands exert considerable influence on downstream flow regimes at the monthly time scale. The constraint indices are the characteristics of a sub-basin’s long-term hydrological behaviour and may reflect the dynamics of the different components of the catchment water balance such as climate, water storage and different runoff processes. Currently, six constraint indices namely the mean monthly runoff volume (MMQ in m3 *106), mean monthly groundwater recharge depth (MMR in mm), the 10th, 50th and 90th percentiles of the flow duration curve expressed as a fraction of MMQ (Q10/MMQ, Q50/MMQ, Q90/MMQ) and the percentage of time that zero flows are expected (%Zero), are used in the modelling approach. These were judged to be the minimum number of key indices that can discriminate between different hydrological responses. The constraint indices in the framework help to determine an uncertainty range within which behavioural model parameters of the expected hydrological response can be identified. Predictive equations of the constraint indices across all climate and physiographic regions of the Congo Basin were based only on the aridity index because it was the most influential sub-basin attribute (Chapter 5) for which quantitative information was available. The degree of uncertainty in the constraint Q10/MMQ and Q50/MMQ indices is less than 41%, while it is somewhat higher for the mean monthly runoff (MMQ) and Q90/MMQ constraint indices. The established uncertainty ranges of the constraint indices were tested in some selected sub-basins of the Congo Basin, including the Lualaba (93 sub-basins), Sangha (24 sub-basins), Oubangui (19 sub-basins), Batéké plateaux (4 sub-basins), Kasai (4 sub-basins) and Inkisi (3 sub-basins). The results proved useful through the application of a 2-stage uncertainty approach of the PITMAN model. However, it comes out of this study that the application of the original constraint indices ranges (Chapter 5) generated satisfactory simulation results in some areas, while in others both small and large adjustments were required to fully capture some aspects of the observed hydrological responses (Chapter 6). Part of the reason is attributed to the availability and quality of streamflow data used to develop the constraint indices ranges (Chapter 5). The main issue identified in the modelling process was whether the changes made to the original constraints at headwater-gauged sub-basins can be applied to ungauged upstream sub-basins to match the observed flow at downstream gauging stations. Ideally, only gauged sub-basin’s constraints can be easily revised based on the observed flow. However, the refinement made to gauged sub-basins alone may fail to substantially affect the results if ungauged upstream sub-basins exert a major impact on defining downstream hydrological response. The majority of gauging stations used in this analysis are located downstream of many upstream ungauged sub-basins and therefore adjustments were required in ungauged sub-basins. These adjustments consist of shifting the full range of a constraint index either towards higher or lower values, depending on the degree to which the simulated uncertainty bounds depart from the observed flow. While this modelling approach seems effective in capturing many aspects of the hydrological responses with a reduced level of uncertainty compared to a previous study, it is recommended that the approach be extended to the remaining parts of the Congo Basin and assessed under current and future development conditions including environmental changes. A 2D hydrodynamic river-wetland model (LISFLOOD-FP) has been used to explicitly represent the inundation process exchanges between river channels and wetland systems. The hydrodynamic modelling outputs are used to calibrate the PITMAN wetland sub-model parameters. The five hydrodynamic models constructed for Ankoro, Kamalondo, Kundelungu, Mweru and Tshiangalele wetland systems have been partially validated using independent estimates of inundation extents available from Landsat imagery. Other sources of data such as remote sensing of water level altimetry, SAR images and wetland storage estimates may be used to improve the validation results. However, the important objective in this study was to make sure that flow volume exchanges between river channels and their adjacent floodplains were being simulated realistically. The wetland sub-model parameters are calibrated in a spreadsheet version of the PITMAN wetland routine to achieve visual correspondence between the LISFLOOD-FP and PITMAN wetland sub-model outputs (Storage volumes and channel outputs). The hysteretic patterns of the river-wetland processes were quantified using hysteresis indices and were associated with the spill and return flow parameters of the wetland sub-model and eventually with the wetland morphometric characteristics. One example is the scale parameter of the return flow function (AA), which shows a good relationship with the average surface slope of the wetland when the coefficient parameter (BB) of the same function is kept constant to a value of 1.25. The same parameter (AA) is a good indicator of the wetland emptying mechanism. A small AA indicates a wetland that slowly releases its flow, resulting in a highly delayed and attenuated hydrological response in downstream sub-basins. This understanding has a practical advantage for the estimation of the PITMAN wetland parameters in the many areas where it is not possible, or where the resources are not available, to run complex hydrodynamic models (Chapter 7). The inclusion of these LISFLOOD-FP informed wetland parameters in the basin-scale hydrological modelling results in acceptable simulations for the lower Lualaba drainage system. The small wetlands, like Ankoro and Tshiangalele, have a negligible impact on downstream flow regimes, whereas large wetlands, such as Kamalondo and Mweru, have very large impacts. In general, the testing of the original constraint indices in the region of wetlands and further downstream of the Lualaba drainage system has shown acceptable results. However, there remains an unresolved uncertainty issue related to the under and over-estimation of some aspects of the hydrological response at both Mulongo and Ankoro, two gauging stations in the immediate downstream of the Kamalondo wetland system. It is difficult to attribute this uncertainty to Kamalondo wetland parameters alone because many of the incremental sub-basins contributing to wetland inflows are ungauged. The issue at Mulongo is the under simulation of low flow, while the high flows at the Ankoro gauging station are over-simulated. However, the pattern of the calibrated constraint indices in this region (Chapter 8) shows that the under simulation of low flow at Mulongo cannot be attributed to incremental sub-basins (between Bukama, Kapolowe and Mulongo gauging stations), because their Q90/MMQ constraint indices are even slightly above the original constraint ranges, but maintain a spatial consistency with sub-basins of other regions. Similarly, sub-basins located between Mulongo, Luvua and Ankoro gauging stations have high flow indices slightly below the original constraint ranges and therefore they are unlikely to be responsible for the over simulation of high flow at the Ankoro gauging station. These facts highlight the need for a further understanding of the complex wetland system of Kamalondo. Short-term data collection and monitoring programme are required. Important tributaries that drain to this wetland need to be monitored by installing water level loggers and periodically collecting flow data and river bathymetry. This programme should lead to the development of rating curves of wetland input tributaries. This would partially solve the unresolved uncertainty issues at the Ankoro and Mulongo gauging stations. The integrated modelling approach offers many opportunities in the Congo Basin. The quantified and modelled uncertainty helps to identify regions with high uncertainty and allows for the identification of various data collection and management strategies that can potentially contribute to the uncertainty reduction. The quantified channel-wetland exchanges contribute to the improvement of the overall knowledge of water resources estimation within the regions where the effects of wetlands are evident even at the monthly time scale. In contrast, ignoring uncertainty in the estimates of water resources availability means that water resources planning and management decisions in the Congo Basin will continue to be based on inadequate information and unquantified uncertainty, thus increasing the risk associated with water resources decision making. , Thesis (PhD) -- Faculty of Science, Institute for Water Research, 2021
- Full Text:
Constraining the role of carbonate assimilation on spinel stability in oxide ores of the Flatreef, Bushveld Complex, South Africa
- Authors: Dyan, Siyasanga
- Date: 2021-04
- Subjects: Oxide minerals -- South Africa -- Bushveld Complex , Transvaal Supergroup (South Africa) , Magmas -- South Africa -- Bushveld Complex , Petrogenesis -- South Africa -- Bushveld Complex , Spinel group – South Africa -- South Africa -- Bushveld Complex , Dolomite -- South Africa -- Bushveld Complex
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/174578 , vital:42490
- Description: The northern limb of the Bushveld Complex shows significant evidence for footwall rock- magma interaction, as a result of the emplacement of magmas onto the Transvaal Supergroup sediments. The Platreef of the northern limb is known to have involved extensive contamination of the magma. The lateral extension of the Platreef, the Flatreef, is less contaminated and comprises PGE-mineralization and thick chromitite layers. This enables successful stratigraphic correlation to the Upper Critical Zone of the eastern and western limbs of the Bushveld Complex. This study aims at addressing the influence of dolomitic floor rock contamination on the formation of spinels of the Flatreef and how they may differ to their occurrences in the Bushveld Complex elsewhere. Three main drill cores (UMT-345, UMT-335, and UMT-094) from the deep drilling program by Ivanhoe Mine, north of Turfspruit, were logged and sampled. The drill cores contained rocks contaminated by dolomite in varying degrees, depending on the proportion of carbonate xenoliths present. A total of sixty-two samples were obtained from the UG-2- equivalent chromitite seam, down into the hybrid contaminated units (Footwall Assimilation Zone; FAZ). Petrographic examination of the drill cores revealed that the feldspathic pyroxenite and chromitite layers are the most pristine lithologies in the Flatreef. The chromitite layers occur as a semi-massive to massive ores. The FAZ rocks are mainly dominated by the abundance of Al-rich Cr-spinels (Mg#30-80), clinopyroxenes with a high Ca-Tschermak component (up to 35 mol.%), olivines (Fo72-84), and plagioclase (An31-78). Geochemical characteristics of the feldspathic pyroxenite and chromitite seams include low CaO/Al2O3 and Ca/SiO2 ratios, the low abundance of REE and HFSE. In contrast, the FAZ samples display high CaO/Al2O3 and CaO/SiO2 ratios, suggesting mobilization of CaO-rich fluids derived from the associated dolomite xenoliths. Observations from lithostratigraphic element profiles indicate spikes in CaO within FAZ units relative to the feldspathic pyroxene, indicating a secondary source of CaO linked to proximity to carbonate xenoliths intersected in the core. The assimilation-fractional crystallization model performed with the Upper Critical Zone parental melt and dolomite produced assemblages dominated by spinel, olivine, clinopyroxene, and plagioclase, relating to those of the most contaminated rocks of footwall assimilation zones. The model also showed that large quantities of CO2 were produced during assimilation. High amounts of CO2-fluids mobilized in the melt would have interacted with the melt and increased the overall oxidation conditions. Oxygen fugacity (ƒO2) values were constrained from the spinels in the FAZ and chromites in chromitite seams. Spinels within the most contaminated rocks of the FAZ recorded relatively high ƒO2 values ranging between NNO-0.2 and NNO+1.8 (relative to the Nickel-Nickel-Oxide buffer. High ƒO2 values in spinels from the FAZ suggest that the melt interacted with greater amounts of oxidative CO2-fluids during decarbonation reactions. Such high redox conditions could have triggered the saturation and crystallization of spinels. Comparison of mineral compositions and ƒO2 of UG-2 chromites from the Flatreef with UG-2 from the eastern limb, western limb, chromitites from the Platreef and Uitkomst Complex reveal that Flatreef chromites are of most similar to those of the Platreef Uitkosmt Complex. The northern limb and Uitkomst Complex chromites have high ƒO2 values (NNO+0.3 to NNO+1.2), indicating their apparent link to the Malmani dolomite. Interaction of magma with the Malmani dolomite would have produced high quantities of CO2, triggering an increase in oxidizing conditions. Such an effect is most prominent in the Flatreef chromitites that are in contact with the FAZ. The chromites are characterised by high ƒO2 (NNO+1.2) and distinct compositions (low Cr2O3, high Fe3+/Fetotal, and TiO2). Thus, it is proposed that carbonate assimilation in the Flatreef triggered the precipitation of these distinctive chromites proximal to FAZ, due to liberation of substantial amounts of CO2-rich fluids with a highly oxidative capacity. Carbonate assimilation in layered intrusions can be used as a monitor potential precipitation of chromites. , Thesis (MSc)--Rhodes University, Faculty of Science, Department of Geology, 2021
- Full Text:
- Authors: Dyan, Siyasanga
- Date: 2021-04
- Subjects: Oxide minerals -- South Africa -- Bushveld Complex , Transvaal Supergroup (South Africa) , Magmas -- South Africa -- Bushveld Complex , Petrogenesis -- South Africa -- Bushveld Complex , Spinel group – South Africa -- South Africa -- Bushveld Complex , Dolomite -- South Africa -- Bushveld Complex
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/174578 , vital:42490
- Description: The northern limb of the Bushveld Complex shows significant evidence for footwall rock- magma interaction, as a result of the emplacement of magmas onto the Transvaal Supergroup sediments. The Platreef of the northern limb is known to have involved extensive contamination of the magma. The lateral extension of the Platreef, the Flatreef, is less contaminated and comprises PGE-mineralization and thick chromitite layers. This enables successful stratigraphic correlation to the Upper Critical Zone of the eastern and western limbs of the Bushveld Complex. This study aims at addressing the influence of dolomitic floor rock contamination on the formation of spinels of the Flatreef and how they may differ to their occurrences in the Bushveld Complex elsewhere. Three main drill cores (UMT-345, UMT-335, and UMT-094) from the deep drilling program by Ivanhoe Mine, north of Turfspruit, were logged and sampled. The drill cores contained rocks contaminated by dolomite in varying degrees, depending on the proportion of carbonate xenoliths present. A total of sixty-two samples were obtained from the UG-2- equivalent chromitite seam, down into the hybrid contaminated units (Footwall Assimilation Zone; FAZ). Petrographic examination of the drill cores revealed that the feldspathic pyroxenite and chromitite layers are the most pristine lithologies in the Flatreef. The chromitite layers occur as a semi-massive to massive ores. The FAZ rocks are mainly dominated by the abundance of Al-rich Cr-spinels (Mg#30-80), clinopyroxenes with a high Ca-Tschermak component (up to 35 mol.%), olivines (Fo72-84), and plagioclase (An31-78). Geochemical characteristics of the feldspathic pyroxenite and chromitite seams include low CaO/Al2O3 and Ca/SiO2 ratios, the low abundance of REE and HFSE. In contrast, the FAZ samples display high CaO/Al2O3 and CaO/SiO2 ratios, suggesting mobilization of CaO-rich fluids derived from the associated dolomite xenoliths. Observations from lithostratigraphic element profiles indicate spikes in CaO within FAZ units relative to the feldspathic pyroxene, indicating a secondary source of CaO linked to proximity to carbonate xenoliths intersected in the core. The assimilation-fractional crystallization model performed with the Upper Critical Zone parental melt and dolomite produced assemblages dominated by spinel, olivine, clinopyroxene, and plagioclase, relating to those of the most contaminated rocks of footwall assimilation zones. The model also showed that large quantities of CO2 were produced during assimilation. High amounts of CO2-fluids mobilized in the melt would have interacted with the melt and increased the overall oxidation conditions. Oxygen fugacity (ƒO2) values were constrained from the spinels in the FAZ and chromites in chromitite seams. Spinels within the most contaminated rocks of the FAZ recorded relatively high ƒO2 values ranging between NNO-0.2 and NNO+1.8 (relative to the Nickel-Nickel-Oxide buffer. High ƒO2 values in spinels from the FAZ suggest that the melt interacted with greater amounts of oxidative CO2-fluids during decarbonation reactions. Such high redox conditions could have triggered the saturation and crystallization of spinels. Comparison of mineral compositions and ƒO2 of UG-2 chromites from the Flatreef with UG-2 from the eastern limb, western limb, chromitites from the Platreef and Uitkomst Complex reveal that Flatreef chromites are of most similar to those of the Platreef Uitkosmt Complex. The northern limb and Uitkomst Complex chromites have high ƒO2 values (NNO+0.3 to NNO+1.2), indicating their apparent link to the Malmani dolomite. Interaction of magma with the Malmani dolomite would have produced high quantities of CO2, triggering an increase in oxidizing conditions. Such an effect is most prominent in the Flatreef chromitites that are in contact with the FAZ. The chromites are characterised by high ƒO2 (NNO+1.2) and distinct compositions (low Cr2O3, high Fe3+/Fetotal, and TiO2). Thus, it is proposed that carbonate assimilation in the Flatreef triggered the precipitation of these distinctive chromites proximal to FAZ, due to liberation of substantial amounts of CO2-rich fluids with a highly oxidative capacity. Carbonate assimilation in layered intrusions can be used as a monitor potential precipitation of chromites. , Thesis (MSc)--Rhodes University, Faculty of Science, Department of Geology, 2021
- Full Text:
Creating shared value through innovating business models: a case study of the Mapela Water Project
- Authors: Moyo, Bonnie
- Date: 2021-04
- Subjects: Business planning -- South Africa , Strategic planning -- South Africa , Sustainable development -- South Africa , Social responsibility of business -- South Africa , Mineral industries -- South Africa , Mapela Water Project , Hourglass Model
- Language: English
- Type: thesis , text , Masters , MBA
- Identifier: http://hdl.handle.net/10962/177135 , vital:42793
- Description: Shared value creation is a contemporary concept that aims to address the strained relationship between business and society through business models that expand the competitive advantage of business while addressing societal challenges in the business environment. Being a novel concept, studies on how value is created and shared are limited, especially where the unit of analysis is a specific project. This paper investigates how value is created and shared among stakeholders using a water project case study reported as a shared value initiative. The investigation is considered under the Hourglass Model (Ludeke-Freund, Massa, Bocken, Brent and Musango, 2016) as a guiding framework. This sustainable business model is suggested as a business model that creates shared value. The study uses a qualitative research approach to investigate the inputs into the Hourglass Model (Ludeke-Freund et al., 2016) in the form of capitals, briefly considers the business models of specific stakeholders and then analyses the value created, missed and destroyed for each stakeholder through their value creation mechanisms. In the findings, six different capitals are identified from the participating stakeholders, and the value created, destroyed, and missed is discussed in the context of shared value principles. The findings show that capitals are used as inputs into the Hourglass Model and are consumed, created, and regenerated. There is also the realisation from the findings that different stakeholders required different and varying amounts of the six capitals identified. The interconnectedness of the capitals is shown in the study, and the findings show that the context of the environment within which a project operates contributes to the creation of shared value. As with the six capitals, the findings show that multiple stakeholders create shared value confirming stakeholder theory's guiding principles regarding stakeholder salience, which are relevant for creating shared value. Some stakeholders are identified as being more important to creating shared value in the project than others. Trade-offs are then required for value creation from a finite pool of capitals and stakeholders to consider the capitals and stakeholders' long and short-term impacts. Identifying stakeholders and the capitals allowed the researcher to consider the value created, destroyed and missed in the project. This assessment of shared value generated forms part of the findings on business models' outcomes for shared value, summarised for the project. Based on these areas where the outcomes are missing or destroying value, recommendations are made to address these opportunities, and an area of further research is identified. Drawing on these outcomes, developing clusters as per the value creation avenues of shared value would be the most appropriate avenue for this project. The study adds to the shared value body of knowledge by operationalising the Hourglass Model (Ludeke-Freund et al., 2016) and illustrating how the Model can be used to consider shared value creation. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2021
- Full Text:
- Authors: Moyo, Bonnie
- Date: 2021-04
- Subjects: Business planning -- South Africa , Strategic planning -- South Africa , Sustainable development -- South Africa , Social responsibility of business -- South Africa , Mineral industries -- South Africa , Mapela Water Project , Hourglass Model
- Language: English
- Type: thesis , text , Masters , MBA
- Identifier: http://hdl.handle.net/10962/177135 , vital:42793
- Description: Shared value creation is a contemporary concept that aims to address the strained relationship between business and society through business models that expand the competitive advantage of business while addressing societal challenges in the business environment. Being a novel concept, studies on how value is created and shared are limited, especially where the unit of analysis is a specific project. This paper investigates how value is created and shared among stakeholders using a water project case study reported as a shared value initiative. The investigation is considered under the Hourglass Model (Ludeke-Freund, Massa, Bocken, Brent and Musango, 2016) as a guiding framework. This sustainable business model is suggested as a business model that creates shared value. The study uses a qualitative research approach to investigate the inputs into the Hourglass Model (Ludeke-Freund et al., 2016) in the form of capitals, briefly considers the business models of specific stakeholders and then analyses the value created, missed and destroyed for each stakeholder through their value creation mechanisms. In the findings, six different capitals are identified from the participating stakeholders, and the value created, destroyed, and missed is discussed in the context of shared value principles. The findings show that capitals are used as inputs into the Hourglass Model and are consumed, created, and regenerated. There is also the realisation from the findings that different stakeholders required different and varying amounts of the six capitals identified. The interconnectedness of the capitals is shown in the study, and the findings show that the context of the environment within which a project operates contributes to the creation of shared value. As with the six capitals, the findings show that multiple stakeholders create shared value confirming stakeholder theory's guiding principles regarding stakeholder salience, which are relevant for creating shared value. Some stakeholders are identified as being more important to creating shared value in the project than others. Trade-offs are then required for value creation from a finite pool of capitals and stakeholders to consider the capitals and stakeholders' long and short-term impacts. Identifying stakeholders and the capitals allowed the researcher to consider the value created, destroyed and missed in the project. This assessment of shared value generated forms part of the findings on business models' outcomes for shared value, summarised for the project. Based on these areas where the outcomes are missing or destroying value, recommendations are made to address these opportunities, and an area of further research is identified. Drawing on these outcomes, developing clusters as per the value creation avenues of shared value would be the most appropriate avenue for this project. The study adds to the shared value body of knowledge by operationalising the Hourglass Model (Ludeke-Freund et al., 2016) and illustrating how the Model can be used to consider shared value creation. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2021
- Full Text:
Customer perceptions on Customer Relationship Management (CRM) and its possible influence on Revenue Management (RM) at a selected water board in South Africa
- Authors: Manyonganise, Joshua Anesu
- Date: 2021-04
- Subjects: Customer relations -- Management , Revenue management -- South Africa -- Eastern Cape , Municipal government -- South Africa -- Eastern Cape , Municipal services -- South Africa -- Eastern Cape , Water-supply -- South Africa -- Eastern Cape , Amatola Water (Utility) , South Africa. National Water Act, 1998
- Language: English
- Type: thesis , text , Masters , MCom
- Identifier: http://hdl.handle.net/10962/177214 , vital:42800
- Description: The primary activity of water boards is to provide water services (bulk portable, and bulk wastewater) to other water services institutions within its respective service areas. They may perform other activities under conditions set out in the Water Services Act of 1997. Water boards’ revenues come from the municipalities they deliver services to. Not all municipalities have been paying for the services delivered to them, which led to the aim of this study being to gauge the perceptions of Water Board X and Water Board X’s customers of selected Customer Relationship Management (CRM) factors (service quality, customer involvement, customer value, information technology, and management commitment) that may possibly influence Revenue Management (RM). This could possibly assist Water Board X in the future to improve its revenue and debt collection. This thesis employed an interpretivist qualitative research methodology to explore its research aims and objectives. Open-ended semi-structured interviews were conducted with thirteen participants from Water Board X and four municipalities which Water Board X provides services. The data collected from the interviews were analysed manually through thematic analysis. The outcome of the interviews noted that an organisation that delivered high levels of service quality to its customers, could possibly improve its RM as the customers are of the opinion that their needs and requirements have been met and would be willing to pay for the services rendered. It was furthermore found that an organisation that involves its customers could possibly improve its RM as the organisation constantly communicates with its customers during, for example, the different stages of a project to ensure that the organisation does not deliver a project that does not meet the customers’ requirements at the end of the project life cycle. In addition the use of information technology played a pivotal in an organisation as the use of information technology assisted to develop effective methods in customer relationship management such as, data management, improving communication within the organisation, and with the customers, and the decision making. Furthermore, this study suggested the importance for an organisation to add value to the services that they deliver and for an organisation’s management to be committed to ensure that their customers’ expectations and requirements are met. The findings of the study suggest that CRM factors (service quality, customer involvement, customer value, information technology, and management commitment) could influence RM, and it is suggested that Water Board X adopts CRM strategies accordingly to improve its RM. Some of these strategies include adopting a coherent and sustainable revenue strategy through the use of appropriate tariff structures that are simple, equitable, affordable, financially sustainable, and transparent for all; showing commitment by prioritising water loss management and by properly auditing water supplies and water treatment revenue while increasing efficiency in supply and revenue recovery as this allowed Water Board X to better serve its customers, improve its financial standing, and allocate funding for water infrastructure upgrades and to adopt technologies that are on the market as these technologies can detect leakages, manage payments, control water flow and transmit data. , Thesis (MCom) -- Faculty of Commerce, Department of Management, 2021
- Full Text:
- Authors: Manyonganise, Joshua Anesu
- Date: 2021-04
- Subjects: Customer relations -- Management , Revenue management -- South Africa -- Eastern Cape , Municipal government -- South Africa -- Eastern Cape , Municipal services -- South Africa -- Eastern Cape , Water-supply -- South Africa -- Eastern Cape , Amatola Water (Utility) , South Africa. National Water Act, 1998
- Language: English
- Type: thesis , text , Masters , MCom
- Identifier: http://hdl.handle.net/10962/177214 , vital:42800
- Description: The primary activity of water boards is to provide water services (bulk portable, and bulk wastewater) to other water services institutions within its respective service areas. They may perform other activities under conditions set out in the Water Services Act of 1997. Water boards’ revenues come from the municipalities they deliver services to. Not all municipalities have been paying for the services delivered to them, which led to the aim of this study being to gauge the perceptions of Water Board X and Water Board X’s customers of selected Customer Relationship Management (CRM) factors (service quality, customer involvement, customer value, information technology, and management commitment) that may possibly influence Revenue Management (RM). This could possibly assist Water Board X in the future to improve its revenue and debt collection. This thesis employed an interpretivist qualitative research methodology to explore its research aims and objectives. Open-ended semi-structured interviews were conducted with thirteen participants from Water Board X and four municipalities which Water Board X provides services. The data collected from the interviews were analysed manually through thematic analysis. The outcome of the interviews noted that an organisation that delivered high levels of service quality to its customers, could possibly improve its RM as the customers are of the opinion that their needs and requirements have been met and would be willing to pay for the services rendered. It was furthermore found that an organisation that involves its customers could possibly improve its RM as the organisation constantly communicates with its customers during, for example, the different stages of a project to ensure that the organisation does not deliver a project that does not meet the customers’ requirements at the end of the project life cycle. In addition the use of information technology played a pivotal in an organisation as the use of information technology assisted to develop effective methods in customer relationship management such as, data management, improving communication within the organisation, and with the customers, and the decision making. Furthermore, this study suggested the importance for an organisation to add value to the services that they deliver and for an organisation’s management to be committed to ensure that their customers’ expectations and requirements are met. The findings of the study suggest that CRM factors (service quality, customer involvement, customer value, information technology, and management commitment) could influence RM, and it is suggested that Water Board X adopts CRM strategies accordingly to improve its RM. Some of these strategies include adopting a coherent and sustainable revenue strategy through the use of appropriate tariff structures that are simple, equitable, affordable, financially sustainable, and transparent for all; showing commitment by prioritising water loss management and by properly auditing water supplies and water treatment revenue while increasing efficiency in supply and revenue recovery as this allowed Water Board X to better serve its customers, improve its financial standing, and allocate funding for water infrastructure upgrades and to adopt technologies that are on the market as these technologies can detect leakages, manage payments, control water flow and transmit data. , Thesis (MCom) -- Faculty of Commerce, Department of Management, 2021
- Full Text:
Detection and effects of selected pharmaceutical compounds from selected water bodies in the Eastern Cape Province, South Africa
- Authors: Setshedi, Koketso Josinah
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/177074 , vital:42788
- Description: Theses embargoed. Release date March 2023. , Thesis (MSc) -- Faculty of Pharmacy, Department of Pharmaceutical Chemistry, 2021
- Full Text:
- Authors: Setshedi, Koketso Josinah
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/177074 , vital:42788
- Description: Theses embargoed. Release date March 2023. , Thesis (MSc) -- Faculty of Pharmacy, Department of Pharmaceutical Chemistry, 2021
- Full Text: