The application of Classification Trees in the Banking Sector
- Authors: Mtwa, Sithayanda
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/178514 , vital:42946
- Description: Access restricted until April 2026. , Thesis (MSc) -- Faculty of Science, Statistics, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Mtwa, Sithayanda
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/178514 , vital:42946
- Description: Access restricted until April 2026. , Thesis (MSc) -- Faculty of Science, Statistics, 2021
- Full Text:
- Date Issued: 2021-04
The novobiocin-induced turnover of fibronectin via low density lipoprotein receptor-related protein 1 alters matrix morphology with physiological consequences on cell growth and migration
- Authors: Boёl, Natasha Marie-Eraine
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/114778 , vital:34034 , 10.21504/10962/114778
- Description: Fibronectin (FN), an extracellular matrix protein, is secreted as a soluble dimer which is assembled into an insoluble extracellular matrix. The dynamics of FN matrix assembly and degradation play a large role in cell migration and invasion thereby contributing to the metastatic potential of cancer cells. Previous studies have shown the direct binding of Heat Shock Protein 90 kDa (Hsp90) and FN in vitro, and that inhibition of Hsp90 with novobiocin (NOV) caused internalisation of the FN matrix. Low density lipoprotein receptor-related protein 1 (LRP1) is a ubiquitous receptor known to bind both Hsp90 and FN. Using an LRP1 expressing Hs578T breast cancer cell line and an isogenic mouse embryonic fibroblast (MEF) model system of differential LRP1 expression we demonstrate that LRP1 is involved in turnover of FN in response to C-terminal Hsp90 inhibition. The first objective of this study was to identify the mechanism of NOV-induced LRP1-mediated FN turnover. Our data show that NOV-mediated FN turnover via LRP1 did not require the activity of matrix metalloproteinases (MMPs), which play an important role in processing and degradation of the extracellular matrix and FN. In addition, the levels of the main FN receptor responsible for its extracellular assembly, β1-integrin, did not change in response to NOV. LRP1 is known to undergo regulated intramembrane proteolysis (RIP) which generates smaller fragments that may translocate to the nucleus and modulate gene transcription. Using inhibitors of LRP1 cleavage and nuclear fractionation we determined that LRP1 processing was not required for the NOV-induced FN response suggesting that a mechanism unrelated to LRP1 RIP is involved. A possible mechanism may be in altered Hsp90-LRP1 cell signalling as we observed disruption of the FN-Hsp90-LRP1 complex at the cell surface in NOV treated cells. How this affects downstream eHsp90-LRP1 signalling is still to be determined but may be related to a significant increase in phospho-AKT and loss of phospho-ERK upon NOV-treatment; two key signalling proteins involved in FN matrix regulation and which are downstream of LRP1 signalling. The second objective of this study was to determine the physiological consequences associated with FN turnover in response to NOV treatment. Using migration assays we demonstrated that levels of insoluble matrix-associated FN and FN concentration are not solely responsible for migratory capacity of cells on decellularized extracellular matrices, but rather that structural composition and integrity of the matrix plays a bigger role. Using confocal and scanning electron microscopy, we identified NOV treated matrices to be flatter, less mature and contain thicker, rope-like FN fibrils to which cells adhered better but were generally less proliferative. Comparatively, cells adhered less to the more mature and 3-dimensional untreated matrices but exhibited increased spreading and cell growth, which may in part be due to the thinner fibrils and web-like matrix. In summary, this study substantiates the role of LRP1 in NOV-mediated FN turnover, and provides new insights into the possible mechanisms of the Hsp90-LRP1 mediated loss of FN matrix. This is the first study to demonstrate some of the functional consequences related to FN turnover by NOV at the ECM level. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2020
- Full Text: false
- Date Issued: 2020
- Authors: Boёl, Natasha Marie-Eraine
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/114778 , vital:34034 , 10.21504/10962/114778
- Description: Fibronectin (FN), an extracellular matrix protein, is secreted as a soluble dimer which is assembled into an insoluble extracellular matrix. The dynamics of FN matrix assembly and degradation play a large role in cell migration and invasion thereby contributing to the metastatic potential of cancer cells. Previous studies have shown the direct binding of Heat Shock Protein 90 kDa (Hsp90) and FN in vitro, and that inhibition of Hsp90 with novobiocin (NOV) caused internalisation of the FN matrix. Low density lipoprotein receptor-related protein 1 (LRP1) is a ubiquitous receptor known to bind both Hsp90 and FN. Using an LRP1 expressing Hs578T breast cancer cell line and an isogenic mouse embryonic fibroblast (MEF) model system of differential LRP1 expression we demonstrate that LRP1 is involved in turnover of FN in response to C-terminal Hsp90 inhibition. The first objective of this study was to identify the mechanism of NOV-induced LRP1-mediated FN turnover. Our data show that NOV-mediated FN turnover via LRP1 did not require the activity of matrix metalloproteinases (MMPs), which play an important role in processing and degradation of the extracellular matrix and FN. In addition, the levels of the main FN receptor responsible for its extracellular assembly, β1-integrin, did not change in response to NOV. LRP1 is known to undergo regulated intramembrane proteolysis (RIP) which generates smaller fragments that may translocate to the nucleus and modulate gene transcription. Using inhibitors of LRP1 cleavage and nuclear fractionation we determined that LRP1 processing was not required for the NOV-induced FN response suggesting that a mechanism unrelated to LRP1 RIP is involved. A possible mechanism may be in altered Hsp90-LRP1 cell signalling as we observed disruption of the FN-Hsp90-LRP1 complex at the cell surface in NOV treated cells. How this affects downstream eHsp90-LRP1 signalling is still to be determined but may be related to a significant increase in phospho-AKT and loss of phospho-ERK upon NOV-treatment; two key signalling proteins involved in FN matrix regulation and which are downstream of LRP1 signalling. The second objective of this study was to determine the physiological consequences associated with FN turnover in response to NOV treatment. Using migration assays we demonstrated that levels of insoluble matrix-associated FN and FN concentration are not solely responsible for migratory capacity of cells on decellularized extracellular matrices, but rather that structural composition and integrity of the matrix plays a bigger role. Using confocal and scanning electron microscopy, we identified NOV treated matrices to be flatter, less mature and contain thicker, rope-like FN fibrils to which cells adhered better but were generally less proliferative. Comparatively, cells adhered less to the more mature and 3-dimensional untreated matrices but exhibited increased spreading and cell growth, which may in part be due to the thinner fibrils and web-like matrix. In summary, this study substantiates the role of LRP1 in NOV-mediated FN turnover, and provides new insights into the possible mechanisms of the Hsp90-LRP1 mediated loss of FN matrix. This is the first study to demonstrate some of the functional consequences related to FN turnover by NOV at the ECM level. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2020
- Full Text: false
- Date Issued: 2020
Political constellations: an analysis of the use of language in positioning South African political parties in the Daily Sun
- Authors: Siebörger, Ian
- Date: 2019
- Subjects: Knowledge, Theory of , Political culture South Africa , Systemic grammar , Political parties South Africa , Functionalism (Linguistics) , Mass media and language South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/113934 , vital:33846 , http://doi.org/10.21504/10962/113934
- Description: As a young democracy, post-apartheid South Africa has both a complex and rapidly changing political landscape, and a developing system of interconnected public spheres in which ordinary citizens engage in political discourses. In this context, this thesis examines the ways in which language is used to position South Africa's political parties in the Daily Sun, the country's most widely-read tabloid newspaper. It uses a complex, multi-stage method of analysis to develop tools for describing how different policy positions and moral evaluations are associated with political parties. This is accomplished through complementary analyses using Systemic Functional Linguistics (SFL) and Legitimation Code Theory (LCT). The study describes current political discourses in South Africa as the products of a long process of historical development extending through the segregationist and apartheid eras to the post-apartheid present. It also situates the Daily Sun within South Africa's current media landscape and argues that the newspaper is to some extent successful in facilitating a vibrant alternative public sphere in which readers engage with the news. The study's multi-stage method of analysis begins with a corpus analysis of all political news articles from the Daily Sun dating from January to June 2015. This analysis reveals various tendencies in the positioning of South Africa's three largest political parties that are investigated further in later stages of analysis. Three selected individual articles are subjected to _ne-grained analysis in an exploratory analysis stage, and three others in a targeted analysis stage. The exploratory analyses are designed to investigate the contribution of various linguistic and discursive resources to political positioning in the data, while the targeted analyses demonstrate the contribution of these resources to positioning in articles that were carefully selected to reflect as many of the trends found in the corpus analysis as possible. These analyses enact the concept of axiological-semantic density from LCT to show the ways in which political knowledge is condensed in the articles. This condensation produces constellations of people, policy positions and moral evaluations in each article. These constellations, in turn, give indications of the cosmologies, or organizing principles, behind the Daily Sun's political news coverage. On the basis of the exploratory analyses, a multi-level translation device for axiological-semantic density is developed to describe the ways in which this concept is enacted in the analysis. The use of this translation device is then demonstrated using the targeted analyses. This study adapts the concepts of iconization, aggregation and technicality from SFL, collectively referred to as 'mass', to show how language works to position political parties. It finds that the use of intertextual references and lexical strings makes a considerable contribution toward political positioning in the data. Repeated couplings of the abovementioned resources in complexes (also known as syndromes) drive the process of political positioning. The Daily Sun is found to report primarily on concrete actions by individual politicians, and contains little to no information on policy decisions. No one political party is favoured, but coverage tends to emphasize accusations against politicians. This may reinforce distrust in politics and a withdrawal from engagement in political processes among readers. By contrast, this study shows that engagement in South Africa's public discourses can be encouraged through stronger promotion of critical language awareness in education, the growth of civil society organizations as vehicles for dialogue and social action on matters of public interest, and a variety of initiatives by the media designed to show the relevance of policy decisions to individuals' lives and increase participation in the news-making process. , Thesis (PhD) -- Faculty of Humanities, English Language and Linguistics, 2019
- Full Text: false
- Date Issued: 2019
- Authors: Siebörger, Ian
- Date: 2019
- Subjects: Knowledge, Theory of , Political culture South Africa , Systemic grammar , Political parties South Africa , Functionalism (Linguistics) , Mass media and language South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/113934 , vital:33846 , http://doi.org/10.21504/10962/113934
- Description: As a young democracy, post-apartheid South Africa has both a complex and rapidly changing political landscape, and a developing system of interconnected public spheres in which ordinary citizens engage in political discourses. In this context, this thesis examines the ways in which language is used to position South Africa's political parties in the Daily Sun, the country's most widely-read tabloid newspaper. It uses a complex, multi-stage method of analysis to develop tools for describing how different policy positions and moral evaluations are associated with political parties. This is accomplished through complementary analyses using Systemic Functional Linguistics (SFL) and Legitimation Code Theory (LCT). The study describes current political discourses in South Africa as the products of a long process of historical development extending through the segregationist and apartheid eras to the post-apartheid present. It also situates the Daily Sun within South Africa's current media landscape and argues that the newspaper is to some extent successful in facilitating a vibrant alternative public sphere in which readers engage with the news. The study's multi-stage method of analysis begins with a corpus analysis of all political news articles from the Daily Sun dating from January to June 2015. This analysis reveals various tendencies in the positioning of South Africa's three largest political parties that are investigated further in later stages of analysis. Three selected individual articles are subjected to _ne-grained analysis in an exploratory analysis stage, and three others in a targeted analysis stage. The exploratory analyses are designed to investigate the contribution of various linguistic and discursive resources to political positioning in the data, while the targeted analyses demonstrate the contribution of these resources to positioning in articles that were carefully selected to reflect as many of the trends found in the corpus analysis as possible. These analyses enact the concept of axiological-semantic density from LCT to show the ways in which political knowledge is condensed in the articles. This condensation produces constellations of people, policy positions and moral evaluations in each article. These constellations, in turn, give indications of the cosmologies, or organizing principles, behind the Daily Sun's political news coverage. On the basis of the exploratory analyses, a multi-level translation device for axiological-semantic density is developed to describe the ways in which this concept is enacted in the analysis. The use of this translation device is then demonstrated using the targeted analyses. This study adapts the concepts of iconization, aggregation and technicality from SFL, collectively referred to as 'mass', to show how language works to position political parties. It finds that the use of intertextual references and lexical strings makes a considerable contribution toward political positioning in the data. Repeated couplings of the abovementioned resources in complexes (also known as syndromes) drive the process of political positioning. The Daily Sun is found to report primarily on concrete actions by individual politicians, and contains little to no information on policy decisions. No one political party is favoured, but coverage tends to emphasize accusations against politicians. This may reinforce distrust in politics and a withdrawal from engagement in political processes among readers. By contrast, this study shows that engagement in South Africa's public discourses can be encouraged through stronger promotion of critical language awareness in education, the growth of civil society organizations as vehicles for dialogue and social action on matters of public interest, and a variety of initiatives by the media designed to show the relevance of policy decisions to individuals' lives and increase participation in the news-making process. , Thesis (PhD) -- Faculty of Humanities, English Language and Linguistics, 2019
- Full Text: false
- Date Issued: 2019
A critical examination of the regulation of fixed term employment services under South African Labour Laws
- Authors: Faku, Xolisa
- Date: 2018-12
- Subjects: Labor laws and legislation , Labor contract , Industrial relations
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/23034 , vital:55101
- Description: South Africa is the most unequal society on the planet, overwhelming Brazil, with a critical increment in wage inequalities. In a quest to reduce unemployment, this research is at the focal point of our nation's activity emergency. In any case, there ought to be components to ensure representation against oppressive work rehearses. The Labour Relations Act denoted a noteworthy change in South Africa's statutory modern relations framework. Following the progress to political majority rule government, the LRA embodied the new government's means to remake and democratize the economy and society as connected in the work relations field. Specifically, it presented new organizations went for giving managers and labourers a chance to break with the serious adversarialism that portrayed their relations before. In extending the equitable change, the Labour Relations Act which offered ascend to the foundation of the National Economic Development and Labour Council (NEDLAC) appeared on 18 February 1995, in an offer to add authenticity and straightforwardness to the financial basic leadership process. This research will investigate the law representing fixed term employment in South Africa. It will further give an investigation of the legitimate framework of fixed term representative keeping in mind the end goal to decide if it advances not too bad work in South Africa. This investigation intends to call attention to any substantive and procedural imperfections that might be accessible in the law. The study will likewise be taking the potential lessons which can be gained from different nations with comparative Fixed-term work challenges i.e. Namibia. This implies the examination will survey the current zone of law and propose an alternate approach. This will be finished by investigating important case law and enactments which secure settled term business. In certainty, the investigation intends to give new point of view regarding the matter of fixed term work and proffer a few changes to the law. , Thesis (MA) -- Faculty of Law, 2018
- Full Text:
- Date Issued: 2018-12
- Authors: Faku, Xolisa
- Date: 2018-12
- Subjects: Labor laws and legislation , Labor contract , Industrial relations
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/23034 , vital:55101
- Description: South Africa is the most unequal society on the planet, overwhelming Brazil, with a critical increment in wage inequalities. In a quest to reduce unemployment, this research is at the focal point of our nation's activity emergency. In any case, there ought to be components to ensure representation against oppressive work rehearses. The Labour Relations Act denoted a noteworthy change in South Africa's statutory modern relations framework. Following the progress to political majority rule government, the LRA embodied the new government's means to remake and democratize the economy and society as connected in the work relations field. Specifically, it presented new organizations went for giving managers and labourers a chance to break with the serious adversarialism that portrayed their relations before. In extending the equitable change, the Labour Relations Act which offered ascend to the foundation of the National Economic Development and Labour Council (NEDLAC) appeared on 18 February 1995, in an offer to add authenticity and straightforwardness to the financial basic leadership process. This research will investigate the law representing fixed term employment in South Africa. It will further give an investigation of the legitimate framework of fixed term representative keeping in mind the end goal to decide if it advances not too bad work in South Africa. This investigation intends to call attention to any substantive and procedural imperfections that might be accessible in the law. The study will likewise be taking the potential lessons which can be gained from different nations with comparative Fixed-term work challenges i.e. Namibia. This implies the examination will survey the current zone of law and propose an alternate approach. This will be finished by investigating important case law and enactments which secure settled term business. In certainty, the investigation intends to give new point of view regarding the matter of fixed term work and proffer a few changes to the law. , Thesis (MA) -- Faculty of Law, 2018
- Full Text:
- Date Issued: 2018-12
Genetic diversity, resistance profile of HIV and risk assessment of mother-to-child transmission in pregnant women on anti-retroviral therapy in the Eastern Cape, South Africa
- Authors: Adeniyi, Oladele Vincent
- Date: 2018-12
- Subjects: Antiretroviral agents , AIDS (Disease) in infants
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/19817 , vital:43254
- Description: Despite the initiation of life-long ART in HIV-infected pregnant women, the rate and determinants of infant HIV transmission are not known, especially in the poor resource settings of the Eastern Cape, South Africa. Maternal anti-retroviral therapy (ART) is crucial for elimination of mother-to-child transmission (MTCT) of HIV. However, the inevitable risks of emergence of HIV drug resistance poses significant threat to achieving this goal of HIV-free generation and keeping mothers alive. Also, it is unclear if women with high viral load at delivery have acquired clinically relevant mutations, which could confer resistance to the ART, thus, further increasing the risks of motherto- child transmission of HIV-drug resistance strains. In addition to the gaps identified in the prevention of mother-to-child transmission (PMTCT) context, the understanding of regional epidemics is crucial to the broader epidemiological profiling of HIV infections in the country. Despite the rapid influx of foreign nationals to South African and Eastern Cape Province, there has not been any molecular epidemiological studies profiling the HIV diversity in the Eastern Cape. , Thesis (PhD) (Microbiology) -- University of Fort Hare, 2018
- Full Text:
- Date Issued: 2018-12
- Authors: Adeniyi, Oladele Vincent
- Date: 2018-12
- Subjects: Antiretroviral agents , AIDS (Disease) in infants
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/19817 , vital:43254
- Description: Despite the initiation of life-long ART in HIV-infected pregnant women, the rate and determinants of infant HIV transmission are not known, especially in the poor resource settings of the Eastern Cape, South Africa. Maternal anti-retroviral therapy (ART) is crucial for elimination of mother-to-child transmission (MTCT) of HIV. However, the inevitable risks of emergence of HIV drug resistance poses significant threat to achieving this goal of HIV-free generation and keeping mothers alive. Also, it is unclear if women with high viral load at delivery have acquired clinically relevant mutations, which could confer resistance to the ART, thus, further increasing the risks of motherto- child transmission of HIV-drug resistance strains. In addition to the gaps identified in the prevention of mother-to-child transmission (PMTCT) context, the understanding of regional epidemics is crucial to the broader epidemiological profiling of HIV infections in the country. Despite the rapid influx of foreign nationals to South African and Eastern Cape Province, there has not been any molecular epidemiological studies profiling the HIV diversity in the Eastern Cape. , Thesis (PhD) (Microbiology) -- University of Fort Hare, 2018
- Full Text:
- Date Issued: 2018-12
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