A critical investigation of leadership in a Technical, Vocational Education and Training college in the Eastern Cape
- Authors: Chagi, Nonkonzo
- Date: 2020
- Subjects: Technical education -- South Africa , Vocational education -- South Africa , Educational leadership -- South Africa , Postsecondary education -- South Africa -- Administration
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/140045 , vital:37827
- Description: Far-reaching reforms of the TVET college system – including a merger and frequent revisioning of the colleges’ role in the educational landscape of South Africa – have focused renewed attention on this sector. The fact that the sector has been plagued by poor performance – even to the extent that several colleges have been placed under administration – suggests problems at the level of leadership. This study sought to explore key role-players’ understanding of the leadership and management challenges faced by a TVET college and, by examining responses to these challenges, develop a sense of what leadership means in the sector. The study drew on three leadership theories – distributed leadership, transactional leadership as depicted in political models of management, and critical leadership – to help make sense of the findings. A qualitative case study design was used to explore key respondents’ views and lived experiences. The respondents were the principal, two deputy principals, a council member, three campus managers and a programme head. Interviews, questionnaires and document analysis were the chief data collection tools. The study found that critical leadership was the dominant approach at the college. This was revealed in the college leadership’s awareness of broader societal needs and its own role in operating in a socially just manner. College leadership also revealed signs of rejecting the status quo and opposing state control and bureaucracy, in favour of reactionary initiatives. There was limited evidence of distributed and transactional leadership. In fact, ‘leadership’ as such, seemed not to be part of the college discourse, suggesting that the concept and habit of leadership was not broadly discussed, shared and promoted. This sense was strengthened by the fact that at the time of the study, the college was headed by a charismatic and visionary leader. Indeed, the problem at the college seemed to be the Department of Higher Education and Training, which has failed the college in a number of ways.
- Full Text:
- Date Issued: 2020
- Authors: Chagi, Nonkonzo
- Date: 2020
- Subjects: Technical education -- South Africa , Vocational education -- South Africa , Educational leadership -- South Africa , Postsecondary education -- South Africa -- Administration
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/140045 , vital:37827
- Description: Far-reaching reforms of the TVET college system – including a merger and frequent revisioning of the colleges’ role in the educational landscape of South Africa – have focused renewed attention on this sector. The fact that the sector has been plagued by poor performance – even to the extent that several colleges have been placed under administration – suggests problems at the level of leadership. This study sought to explore key role-players’ understanding of the leadership and management challenges faced by a TVET college and, by examining responses to these challenges, develop a sense of what leadership means in the sector. The study drew on three leadership theories – distributed leadership, transactional leadership as depicted in political models of management, and critical leadership – to help make sense of the findings. A qualitative case study design was used to explore key respondents’ views and lived experiences. The respondents were the principal, two deputy principals, a council member, three campus managers and a programme head. Interviews, questionnaires and document analysis were the chief data collection tools. The study found that critical leadership was the dominant approach at the college. This was revealed in the college leadership’s awareness of broader societal needs and its own role in operating in a socially just manner. College leadership also revealed signs of rejecting the status quo and opposing state control and bureaucracy, in favour of reactionary initiatives. There was limited evidence of distributed and transactional leadership. In fact, ‘leadership’ as such, seemed not to be part of the college discourse, suggesting that the concept and habit of leadership was not broadly discussed, shared and promoted. This sense was strengthened by the fact that at the time of the study, the college was headed by a charismatic and visionary leader. Indeed, the problem at the college seemed to be the Department of Higher Education and Training, which has failed the college in a number of ways.
- Full Text:
- Date Issued: 2020
Social circumstances and cultural beliefs influence maternal nutrition, breastfeeding and child feeding practices in South Africa:
- Authors: Chakona, Gamuchirai
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148627 , vital:38757 , https://nutritionj.biomedcentral.com/articles/10.1186/s12937-020-00566-4
- Description: Maternal and child undernutrition remain prevalent in developing countries with 45 and 11% of child deaths linked to poor nutrition and suboptimal breastfeeding, respectively. This also has adverse effects on child growth and development. The study determined maternal dietary diversity, breastfeeding and, infant and young child feeding (IYCF) practices and identified reasons for such behavior in five rural communities in South Africa, in the context of cultural beliefs and social aspects.
- Full Text:
- Date Issued: 2020
- Authors: Chakona, Gamuchirai
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148627 , vital:38757 , https://nutritionj.biomedcentral.com/articles/10.1186/s12937-020-00566-4
- Description: Maternal and child undernutrition remain prevalent in developing countries with 45 and 11% of child deaths linked to poor nutrition and suboptimal breastfeeding, respectively. This also has adverse effects on child growth and development. The study determined maternal dietary diversity, breastfeeding and, infant and young child feeding (IYCF) practices and identified reasons for such behavior in five rural communities in South Africa, in the context of cultural beliefs and social aspects.
- Full Text:
- Date Issued: 2020
Evaluation of the role of ethical leadership development on organisational performance: the case of Econet Wireless Zimbabwe
- Authors: Chakonza, Hawkins
- Date: 2020
- Subjects: Econet Wireless Zimbabwe , Leadership , Leadership -- Case studies , Business ethics
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/146723 , vital:38551
- Description: The study evaluated the role of ethical leadership development on the performance of the organisation. Econet Wireless Zimbabwe was employed as a case study. The objectives of the study were to: understand the role of ethical leadership development at Econet Wireless Zimbabwe on the day to day running of the business, understand the nature of the ethical leadership development at Econet Wireless, examine the factors influencing ethical leadership development at Econet Wireless, ascertain the role of ethical leadership development in enhancing organisational perfomance and efficiency and to investigate leaders’ perceptions on ethical leadership development on the organisation’s effectiveness. Social learning and social exchange theory informed the study. The research employed a qualitatve approache to improve the validity,reliability and credibility of the research findings. key informnat intervews and focus group of discussion and in-depth interviews were used as data collection instruments. The study found that ethical leadership development programmes improve the perfomance of orgnisations. That is, ethical leadeship development enbaled Econet Wireless Zimbabwe to achive disticinive competence, increase profit, have a large number of subscribers and also expanded among others. Furthermore, the study shows that an ethical leadership development approach brings significant value to the organisation and, suggests that ethical leaders are more influential in organizations than currently understood. The study found that leaders could influence ethics related outcomes in the organisation by engaging in behaviours that makes them perceived as credible, attractive and legitimate by their followers.
- Full Text:
- Date Issued: 2020
- Authors: Chakonza, Hawkins
- Date: 2020
- Subjects: Econet Wireless Zimbabwe , Leadership , Leadership -- Case studies , Business ethics
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/146723 , vital:38551
- Description: The study evaluated the role of ethical leadership development on the performance of the organisation. Econet Wireless Zimbabwe was employed as a case study. The objectives of the study were to: understand the role of ethical leadership development at Econet Wireless Zimbabwe on the day to day running of the business, understand the nature of the ethical leadership development at Econet Wireless, examine the factors influencing ethical leadership development at Econet Wireless, ascertain the role of ethical leadership development in enhancing organisational perfomance and efficiency and to investigate leaders’ perceptions on ethical leadership development on the organisation’s effectiveness. Social learning and social exchange theory informed the study. The research employed a qualitatve approache to improve the validity,reliability and credibility of the research findings. key informnat intervews and focus group of discussion and in-depth interviews were used as data collection instruments. The study found that ethical leadership development programmes improve the perfomance of orgnisations. That is, ethical leadeship development enbaled Econet Wireless Zimbabwe to achive disticinive competence, increase profit, have a large number of subscribers and also expanded among others. Furthermore, the study shows that an ethical leadership development approach brings significant value to the organisation and, suggests that ethical leaders are more influential in organizations than currently understood. The study found that leaders could influence ethics related outcomes in the organisation by engaging in behaviours that makes them perceived as credible, attractive and legitimate by their followers.
- Full Text:
- Date Issued: 2020
The Role of HSP70/HSP90 Organizing Protein (Hop) in the Heat Shock Factor 1 (HSF1)-mediated Stress Response
- Authors: Chakraborty, Abantika
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/163204 , vital:41018 , doi:10.21504/10962/163204
- Description: Molecular chaperones regulate cellular proteostasis. They control protein conformation and prevent misfolding and aggregation under both normal and stressful environments, ultimately resulting in cell survival. The project aimed to understand the role of the HSP70 – HSP90 Organizing Protein (Hop/STIP1) in the survival of stressed cells and the function of the stress-responsive transcription factor, Heat Shock Factor 1 (HSF1). HSF1 protein levels were significantly reduced in Hop-depleted HEK293T cells compared to controls by ELISA, western blot, and mass spectrometry. HSF1 transcriptional activity at the HSP70 promoter, and binding of a biotinylated HSE oligonucleotide under basal conditions were significantly reduced, consistent with the reduced levels of HSF1. In response to heat shock, HSF1 levels in Hop-depleted cells increased to that of controls, but there was still significantly lowerHSF1 transcriptional activity and HSE binding. Hop-depleted HEK293T cells were more sensitive than controls to the HSF1 inhibitor KRIBB11 and showed reduced short-term and long-term proliferation. Unlike the HSP90 inhibitor 17-DMAG, which had no effect, the HSP70 inhibitor JG98, further decreased the levels of HSF1 in Hop-depleted cells, suggesting a role for HSP70 in the Hop-mediated effects. There was punctate nuclear staining for HSF1 in Hop-depleted cells under both basal and heat shock conditions, as well as reduced nuclear localization and increased cytoplasmic accumulation of HSF1 in response to heat shock. Hop and HSF1 colocalized in cells, and HSF1 could be isolated in complex with Hop and HSP70. Loss of Hop reduced HSF1 in HSP70complexes but did not affect HSF1 abundance in HSP90 complexes. Hop-depleted cells showed reduced short-term and long-term survival compared to controls, an effect that was potentiated by the JG98 HSP70 inhibitor. Taken together, these data suggest that Hop regulation of HSF1activity is via a mechanism involving reductions in HSP70 interaction, as well as reduced nuclear localization, and DNA binding, and is consistent with reduced cellular fitness under basal and stress conditions. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2020
- Full Text:
- Date Issued: 2020
- Authors: Chakraborty, Abantika
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/163204 , vital:41018 , doi:10.21504/10962/163204
- Description: Molecular chaperones regulate cellular proteostasis. They control protein conformation and prevent misfolding and aggregation under both normal and stressful environments, ultimately resulting in cell survival. The project aimed to understand the role of the HSP70 – HSP90 Organizing Protein (Hop/STIP1) in the survival of stressed cells and the function of the stress-responsive transcription factor, Heat Shock Factor 1 (HSF1). HSF1 protein levels were significantly reduced in Hop-depleted HEK293T cells compared to controls by ELISA, western blot, and mass spectrometry. HSF1 transcriptional activity at the HSP70 promoter, and binding of a biotinylated HSE oligonucleotide under basal conditions were significantly reduced, consistent with the reduced levels of HSF1. In response to heat shock, HSF1 levels in Hop-depleted cells increased to that of controls, but there was still significantly lowerHSF1 transcriptional activity and HSE binding. Hop-depleted HEK293T cells were more sensitive than controls to the HSF1 inhibitor KRIBB11 and showed reduced short-term and long-term proliferation. Unlike the HSP90 inhibitor 17-DMAG, which had no effect, the HSP70 inhibitor JG98, further decreased the levels of HSF1 in Hop-depleted cells, suggesting a role for HSP70 in the Hop-mediated effects. There was punctate nuclear staining for HSF1 in Hop-depleted cells under both basal and heat shock conditions, as well as reduced nuclear localization and increased cytoplasmic accumulation of HSF1 in response to heat shock. Hop and HSF1 colocalized in cells, and HSF1 could be isolated in complex with Hop and HSP70. Loss of Hop reduced HSF1 in HSP70complexes but did not affect HSF1 abundance in HSP90 complexes. Hop-depleted cells showed reduced short-term and long-term survival compared to controls, an effect that was potentiated by the JG98 HSP70 inhibitor. Taken together, these data suggest that Hop regulation of HSF1activity is via a mechanism involving reductions in HSP70 interaction, as well as reduced nuclear localization, and DNA binding, and is consistent with reduced cellular fitness under basal and stress conditions. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2020
- Full Text:
- Date Issued: 2020
Hop depletion reduces HSF1 levels and activity and coincides with reduced stress resilience:
- Chakraborty, Abantika, Edkins, Adrienne L
- Authors: Chakraborty, Abantika , Edkins, Adrienne L
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165440 , vital:41244 , https://doi.org/10.1016/j.bbrc.2020.04.072
- Description: Heat-shock factor 1 (HSF1) regulates the transcriptional response to stress and controls expression of molecular chaperones required for cell survival. Here we report that HSF1 is regulated by the abundance of the Hsp70-Hsp90 organizing protein (Hop/STIP1).
- Full Text:
- Date Issued: 2020
- Authors: Chakraborty, Abantika , Edkins, Adrienne L
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165440 , vital:41244 , https://doi.org/10.1016/j.bbrc.2020.04.072
- Description: Heat-shock factor 1 (HSF1) regulates the transcriptional response to stress and controls expression of molecular chaperones required for cell survival. Here we report that HSF1 is regulated by the abundance of the Hsp70-Hsp90 organizing protein (Hop/STIP1).
- Full Text:
- Date Issued: 2020
HSP90 interacts with the fibronectin N-terminal domains and increases matrix formation:
- Chakraborty, Abir, Boel, Natasha M-E, Edkins, Adrienne L
- Authors: Chakraborty, Abir , Boel, Natasha M-E , Edkins, Adrienne L
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165407 , vital:41241 , https://doi.org/10.3390/cells9020272
- Description: Heat shock protein 90 (HSP90) is an evolutionarily conserved chaperone protein that controls the function and stability of a wide range of cellular client proteins. Fibronectin (FN) is an extracellular client protein of HSP90, and exogenous HSP90 or inhibitors of HSP90 alter the morphology of the extracellular matrix. Here, we further characterized the HSP90 and FN interaction. FN bound to the M domain of HSP90 and interacted with both the open and closed HSP90 conformations; and the interaction was reduced in the presence of sodium molybdate. HSP90 interacted with the N-terminal regions of FN, which are known to be important for matrix assembly.
- Full Text:
- Date Issued: 2020
- Authors: Chakraborty, Abir , Boel, Natasha M-E , Edkins, Adrienne L
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165407 , vital:41241 , https://doi.org/10.3390/cells9020272
- Description: Heat shock protein 90 (HSP90) is an evolutionarily conserved chaperone protein that controls the function and stability of a wide range of cellular client proteins. Fibronectin (FN) is an extracellular client protein of HSP90, and exogenous HSP90 or inhibitors of HSP90 alter the morphology of the extracellular matrix. Here, we further characterized the HSP90 and FN interaction. FN bound to the M domain of HSP90 and interacted with both the open and closed HSP90 conformations; and the interaction was reduced in the presence of sodium molybdate. HSP90 interacted with the N-terminal regions of FN, which are known to be important for matrix assembly.
- Full Text:
- Date Issued: 2020
Analysis of bacterial Mur amide ligase enzymes for the identification of inhibitory compounds by in silico methods
- Chamboko, Chiratidzo Respina
- Authors: Chamboko, Chiratidzo Respina
- Date: 2020
- Subjects: Mur amide ligases , Ligases , Ligand binding (Biochemistry) , Antibacterial agents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/163430 , vital:41036
- Description: An increased emergence of resistant pathogenic bacterial strains over the years has resulted in many people dying of untreatable infections. This has become one of the most critical global public health problems, as resistant strains are complicating treatment of infectious diseases, increasing human morbidity, mortality, and health care costs. A very limited amount of effective antibiotics is currently available, but the development of novel classes of antibacterial agents is becoming a priority. Mur amide ligases are enzymes that have been identified as potentially good targets for antibiotics, as they are uniquely found in bacteria. They are responsible for the formation of peptide bonds in a growing peptidoglycan structure for bacterial cell walls. The current work presented here focused on characterizing these Mur amide ligase enzymes and obtaining inhibitory compounds that could potentially be of use in drug discovery of antibacterial agents. To do this, multiple sequence alignment, motif analysis and phylogenetic tree constructions were carried out, followed by docking studies and molecular dynamic simulations. Prior to docking, homology modelling of missing residues in the MurF structure (PDB 1GG4) was performed. Characterization results revealed the Mur amide ligase enzymes contained defined conservation in limited regions, that ultimately mapped towards the central domain responsible for ATP binding (presence of a conserved GKT motif). Further analysis of results further unraveled the unique patterns observed within each group of the family of enzymes. As a result of these findings, docking studies were carried out on each Mur amide ligase structure. At most, two ligands were identified to be sufficiently inhibiting each Mur amide ligase. The ligands obtained were SANC00574 and SANC00575 for MurC, SANC00290 and SANC00438 for MurD, SANC00290 and SANC00525 for MurE and SANC00290 and SANC00434 for MurF. The two best ligands identified for each enzyme had docked in the active site of their respective proteins, passed Lipinski’s rule of five and had substantially low binding energies. Molecular dynamic simulations were then performed to analyze the behavior of the proteins and protein-ligand complexes, to confirm the lead compounds as good inhibitors of the Mur amide ligases. In the case of MurC, MurD and MurE complexes, the identified ligands clearly impacted the behavior of the protein, as the ligand bound proteins became more compact and stable, while flexibility decreased. There was however an opposite effect on MurF complexes, that resulted in identified inhibitors being discarded. As a potential next step, in vivo and in vitro experiments can be performed with identified ligands from this research, to further support the information presented.
- Full Text:
- Date Issued: 2020
- Authors: Chamboko, Chiratidzo Respina
- Date: 2020
- Subjects: Mur amide ligases , Ligases , Ligand binding (Biochemistry) , Antibacterial agents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/163430 , vital:41036
- Description: An increased emergence of resistant pathogenic bacterial strains over the years has resulted in many people dying of untreatable infections. This has become one of the most critical global public health problems, as resistant strains are complicating treatment of infectious diseases, increasing human morbidity, mortality, and health care costs. A very limited amount of effective antibiotics is currently available, but the development of novel classes of antibacterial agents is becoming a priority. Mur amide ligases are enzymes that have been identified as potentially good targets for antibiotics, as they are uniquely found in bacteria. They are responsible for the formation of peptide bonds in a growing peptidoglycan structure for bacterial cell walls. The current work presented here focused on characterizing these Mur amide ligase enzymes and obtaining inhibitory compounds that could potentially be of use in drug discovery of antibacterial agents. To do this, multiple sequence alignment, motif analysis and phylogenetic tree constructions were carried out, followed by docking studies and molecular dynamic simulations. Prior to docking, homology modelling of missing residues in the MurF structure (PDB 1GG4) was performed. Characterization results revealed the Mur amide ligase enzymes contained defined conservation in limited regions, that ultimately mapped towards the central domain responsible for ATP binding (presence of a conserved GKT motif). Further analysis of results further unraveled the unique patterns observed within each group of the family of enzymes. As a result of these findings, docking studies were carried out on each Mur amide ligase structure. At most, two ligands were identified to be sufficiently inhibiting each Mur amide ligase. The ligands obtained were SANC00574 and SANC00575 for MurC, SANC00290 and SANC00438 for MurD, SANC00290 and SANC00525 for MurE and SANC00290 and SANC00434 for MurF. The two best ligands identified for each enzyme had docked in the active site of their respective proteins, passed Lipinski’s rule of five and had substantially low binding energies. Molecular dynamic simulations were then performed to analyze the behavior of the proteins and protein-ligand complexes, to confirm the lead compounds as good inhibitors of the Mur amide ligases. In the case of MurC, MurD and MurE complexes, the identified ligands clearly impacted the behavior of the protein, as the ligand bound proteins became more compact and stable, while flexibility decreased. There was however an opposite effect on MurF complexes, that resulted in identified inhibitors being discarded. As a potential next step, in vivo and in vitro experiments can be performed with identified ligands from this research, to further support the information presented.
- Full Text:
- Date Issued: 2020
Analysis of bacterial Mur amide ligase enzymes for the identification of inhibitory compounds by in silico methods
- Chamboko, Chiratidzo Respina
- Authors: Chamboko, Chiratidzo Respina
- Date: 2020
- Subjects: Pathogenic microorganisms -- Analysis , Drug resistance in microorganisms , Microorganisms -- Effect of drugs on , Antibiotics -- Effectiveness , Pathogenic bacteria , Drug tolerance , Enzymes -- Analysis , Peptide antibiotics
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/161911 , vital:40690
- Description: An increased emergence of resistant pathogenic bacterial strains over the years has resulted in many people dying of untreatable infections. This has become one of the most critical global public health problems, as resistant strains are complicating treatment of infectious diseases, increasing human morbidity, mortality, and health care costs. A very limited amount of effective antibiotics is currently available, but the development of novel classes of antibacterial agents is becoming a priority. Mur amide ligases are enzymes that have been identified as potentially good targets for antibiotics, as they are uniquely found in bacteria. They are responsible for the formation of peptide bonds in a growing peptidoglycan structure for bacterial cell walls. The current work presented here focused on characterizing these Mur amide ligase enzymes and obtaining inhibitory compounds that could potentially be of use in drug discovery of antibacterial agents. To do this, multiple sequence alignment, motif analysis and phylogenetic tree constructions were carried out, followed by docking studies and molecular dynamic simulations. Prior to docking, homology modelling of missing residues in the MurF structure (PDB 1GG4) was performed. Characterization results revealed the Mur amide ligase enzymes contained defined conservation in limited regions, that ultimately mapped towards the central domain responsible for ATP binding (presence of a conserved GKT motif). Further analysis of results further unraveled the unique patterns observed within each group of the family of enzymes. As a result of these findings, docking studies were carried out on each Mur amide ligase structure. At most, two ligands were identified to be sufficiently inhibiting each Mur amide ligase. The ligands obtained were SANC00574 and SANC00575 for MurC, SANC00290 and SANC00438 for MurD, SANC00290 and SANC00525 for MurE and SANC00290 and SANC00434 for MurF. The two best ligands identified for each enzyme had docked in the active site of their respective proteins, passed Lipinski’s rule of five and had substantially low binding energies. Molecular dynamic simulations were then performed to analyze the behavior of the proteins and protein-ligand complexes, to confirm the lead compounds as good inhibitors of the Mur amide ligases. In the case of MurC, MurD and MurE complexes, the identified ligands clearly impacted the behavior of the protein, as the ligand bound proteins became more compact and stable, while flexibility decreased. There was however an opposite effect on MurF complexes, that resulted in identified inhibitors being discarded. As a potential next step, in vivo and in vitro experiments can be performed with identified ligands from this research, to further support the information presented.
- Full Text:
- Date Issued: 2020
- Authors: Chamboko, Chiratidzo Respina
- Date: 2020
- Subjects: Pathogenic microorganisms -- Analysis , Drug resistance in microorganisms , Microorganisms -- Effect of drugs on , Antibiotics -- Effectiveness , Pathogenic bacteria , Drug tolerance , Enzymes -- Analysis , Peptide antibiotics
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/161911 , vital:40690
- Description: An increased emergence of resistant pathogenic bacterial strains over the years has resulted in many people dying of untreatable infections. This has become one of the most critical global public health problems, as resistant strains are complicating treatment of infectious diseases, increasing human morbidity, mortality, and health care costs. A very limited amount of effective antibiotics is currently available, but the development of novel classes of antibacterial agents is becoming a priority. Mur amide ligases are enzymes that have been identified as potentially good targets for antibiotics, as they are uniquely found in bacteria. They are responsible for the formation of peptide bonds in a growing peptidoglycan structure for bacterial cell walls. The current work presented here focused on characterizing these Mur amide ligase enzymes and obtaining inhibitory compounds that could potentially be of use in drug discovery of antibacterial agents. To do this, multiple sequence alignment, motif analysis and phylogenetic tree constructions were carried out, followed by docking studies and molecular dynamic simulations. Prior to docking, homology modelling of missing residues in the MurF structure (PDB 1GG4) was performed. Characterization results revealed the Mur amide ligase enzymes contained defined conservation in limited regions, that ultimately mapped towards the central domain responsible for ATP binding (presence of a conserved GKT motif). Further analysis of results further unraveled the unique patterns observed within each group of the family of enzymes. As a result of these findings, docking studies were carried out on each Mur amide ligase structure. At most, two ligands were identified to be sufficiently inhibiting each Mur amide ligase. The ligands obtained were SANC00574 and SANC00575 for MurC, SANC00290 and SANC00438 for MurD, SANC00290 and SANC00525 for MurE and SANC00290 and SANC00434 for MurF. The two best ligands identified for each enzyme had docked in the active site of their respective proteins, passed Lipinski’s rule of five and had substantially low binding energies. Molecular dynamic simulations were then performed to analyze the behavior of the proteins and protein-ligand complexes, to confirm the lead compounds as good inhibitors of the Mur amide ligases. In the case of MurC, MurD and MurE complexes, the identified ligands clearly impacted the behavior of the protein, as the ligand bound proteins became more compact and stable, while flexibility decreased. There was however an opposite effect on MurF complexes, that resulted in identified inhibitors being discarded. As a potential next step, in vivo and in vitro experiments can be performed with identified ligands from this research, to further support the information presented.
- Full Text:
- Date Issued: 2020
Insect herbivores associated with Lycium ferocissimum (Solanaceae) in South Africa and their potential as biological control agents in Australia
- Chari, Lenon D, Mauda, EV, Martin, Grant D, Raghu, S
- Authors: Chari, Lenon D , Mauda, EV , Martin, Grant D , Raghu, S
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/407035 , vital:70331 , xlink:href="https://hdl.handle.net/10520/EJC-203b8dbc7b"
- Description: Lycium ferocissimum Miers (Solanaceae) is an indigenous shrub in South Africa but has become invasive in several countries including Australia, where chemical and mechanical control methods have proved costly and unsustainable. In Australia, biological control is being considered as a management option, but the herbivorous insects associated with the plant in its native range are not well known. The aim of this study was to survey the phytophagous insects associated with L. ferocissimum in South Africa and prioritise promising biological control agents. In South Africa, the plant occurs in two geographically distinct areas, the Eastern and Western Cape provinces. Surveys for phytophagous insects on L. ferocissimum were carried out repeatedly over a two-year period in these two regions. The number of insect species found in the Eastern Cape Province (55) was higher than that in the WesternCapeProvince (41), but insect diversity based on Shannon indices was highest in the Western Cape Province. Indicator species analysis revealed eight insect herbivore species driving the differences in the herbivore communities between the two provinces. Based on insect distribution, abundance, feeding preference and available literature, three species were prioritised as potential biological control agents. These include the leaf-chewing beetles Cassida distinguenda Spaeth (Chrysomelidae) and Cleta eckloni Mulsant (Coccinellidae) and the leaf-mining weevil Neoplatygaster serietuberculata Gyllenhal (Curculionidae).
- Full Text:
- Date Issued: 2020
- Authors: Chari, Lenon D , Mauda, EV , Martin, Grant D , Raghu, S
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/407035 , vital:70331 , xlink:href="https://hdl.handle.net/10520/EJC-203b8dbc7b"
- Description: Lycium ferocissimum Miers (Solanaceae) is an indigenous shrub in South Africa but has become invasive in several countries including Australia, where chemical and mechanical control methods have proved costly and unsustainable. In Australia, biological control is being considered as a management option, but the herbivorous insects associated with the plant in its native range are not well known. The aim of this study was to survey the phytophagous insects associated with L. ferocissimum in South Africa and prioritise promising biological control agents. In South Africa, the plant occurs in two geographically distinct areas, the Eastern and Western Cape provinces. Surveys for phytophagous insects on L. ferocissimum were carried out repeatedly over a two-year period in these two regions. The number of insect species found in the Eastern Cape Province (55) was higher than that in the WesternCapeProvince (41), but insect diversity based on Shannon indices was highest in the Western Cape Province. Indicator species analysis revealed eight insect herbivore species driving the differences in the herbivore communities between the two provinces. Based on insect distribution, abundance, feeding preference and available literature, three species were prioritised as potential biological control agents. These include the leaf-chewing beetles Cassida distinguenda Spaeth (Chrysomelidae) and Cleta eckloni Mulsant (Coccinellidae) and the leaf-mining weevil Neoplatygaster serietuberculata Gyllenhal (Curculionidae).
- Full Text:
- Date Issued: 2020
Iodine nutrition status in Africa: Potentially high prevalence of iodine deficiency in pregnancy even in countries classified as iodine sufficient
- Charles Bitamazire Businge, Benjamin Longo-Mbenza, Andre Pascal Kengne
- Authors: Charles Bitamazire Businge , Benjamin Longo-Mbenza , Andre Pascal Kengne
- Date: 03-8-2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/3377 , vital:43336 , https://www.cambridge.org/core/journals/public-health-nutrition/article/iodine-nutrition-status-in-africa-potentially-high-prevalence-of-iodine-deficiency-in-pregnancy-even-in-countries-classified-as-iodine-sufficient/B3DCB06E75CDDD8EAD410BE090198BA4
- Description: Objective: To assess the burden of iodine deficiency in pregnancy in Africa using estimated pregnancy median urinary iodine concentration (pMUIC). Design: pMUIC for each African country was estimated using a regression equation derived by correlating the school-age children (SAC) median UIC (mUIC) and pMUIC from countries around the globe, and the SAC mUIC data for African countries obtained from the Iodine Global Network (IGN) 2017 and 2019 Score cards. Setting: Iodine deficiency was endemic in many African countries before the introduction of iodine fortification, mainly through universal salt iodisation programmes about 25 years ago. There is a scarcity of data on the level of iodine nutrition in pregnancy in Africa. Women living in settings with pMUIC below 150 μg/l are at risk of iodine deficiency-related pregnancy complications. Participants: Fifty of the fifty-five African countries that had data on iodine nutrition status. Results: A cut-off school age mUIC ≤ 175 μg/l is correlated with insufficient iodine intake in pregnancy (pregnancy mUIC ≤ 150 μg/l). Twenty-two African countries had SAC mUIC less than 175 μg/l, which correlated with insufficient iodine intake during pregnancy (pMUIC less than 150 μg/l). However, nine of these twenty-two countries had adequate iodine intake based on SAC mUIC. Conclusions: There is likely a high prevalence of insufficient iodine intake in pregnancy, including in some African countries classified as having adequate iodine intake in the general population. A SAC mUIC ≤ 175 μ
- Full Text:
- Date Issued: 03-8-2020
- Authors: Charles Bitamazire Businge , Benjamin Longo-Mbenza , Andre Pascal Kengne
- Date: 03-8-2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/3377 , vital:43336 , https://www.cambridge.org/core/journals/public-health-nutrition/article/iodine-nutrition-status-in-africa-potentially-high-prevalence-of-iodine-deficiency-in-pregnancy-even-in-countries-classified-as-iodine-sufficient/B3DCB06E75CDDD8EAD410BE090198BA4
- Description: Objective: To assess the burden of iodine deficiency in pregnancy in Africa using estimated pregnancy median urinary iodine concentration (pMUIC). Design: pMUIC for each African country was estimated using a regression equation derived by correlating the school-age children (SAC) median UIC (mUIC) and pMUIC from countries around the globe, and the SAC mUIC data for African countries obtained from the Iodine Global Network (IGN) 2017 and 2019 Score cards. Setting: Iodine deficiency was endemic in many African countries before the introduction of iodine fortification, mainly through universal salt iodisation programmes about 25 years ago. There is a scarcity of data on the level of iodine nutrition in pregnancy in Africa. Women living in settings with pMUIC below 150 μg/l are at risk of iodine deficiency-related pregnancy complications. Participants: Fifty of the fifty-five African countries that had data on iodine nutrition status. Results: A cut-off school age mUIC ≤ 175 μg/l is correlated with insufficient iodine intake in pregnancy (pregnancy mUIC ≤ 150 μg/l). Twenty-two African countries had SAC mUIC less than 175 μg/l, which correlated with insufficient iodine intake during pregnancy (pMUIC less than 150 μg/l). However, nine of these twenty-two countries had adequate iodine intake based on SAC mUIC. Conclusions: There is likely a high prevalence of insufficient iodine intake in pregnancy, including in some African countries classified as having adequate iodine intake in the general population. A SAC mUIC ≤ 175 μ
- Full Text:
- Date Issued: 03-8-2020
Screening of ectomycorrhizal and other associated fungi in South African forest nurseries
- Chartier FitzGerald , Veronique, Dames, Joanna F, Hawley, Greer L
- Authors: Chartier FitzGerald , Veronique , Dames, Joanna F , Hawley, Greer L
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426058 , vital:72310 , xlink:href="https://hdl.handle.net/10520/ejc-soufor-v82-n4-a8"
- Description: The South African forestry industry covers approximately 1.3 million hectares and is dependent on exotic pine and eucalypt species. Nursery seedlings are not inoculated with ectomycorrhizal (ECM) fungi. This investigation assessed levels of naturally occurring ECM colonisation of Pinus patula seedlings from 10 different South African forestry nurseries using a grid line intersect method. Fungi from colonised roots were identified using morphological characteristics and Illumina sequencing. Colonisation of seedlings in production nurseries was low (2-21%). Morphologically, the ECM fungi Thelophora terrestris, Suillus sibiricus, and the genera Russula and Pseudotomentella were identified. Molecularly, the ECM fungi T. terrestris, Inocybe jacobi and the genus Sphaerosporella, as well as several other ECM-containing families were identified, along with many saprotrophic/ endophytic fungi belonging to genera such as Penicillium, Ramasonia and Talaromyces. As can be seen, a combination of both molecular and morphological identification techniques are needed as neither is able to give a full picture of the species present in isolation. This study reveals an initial insight into the root microbiome community associated with Pinus patula seedlings, which should be taken into account when inoculation with beneficial microbes is considered. It determined that natural ECM fungal root colonisation levels are very low throughout the South African nurseries investigated, indicating the need for ECM fungal inoculation, which can increase seedling growth, viability and resistance to pathogens.
- Full Text:
- Date Issued: 2020
- Authors: Chartier FitzGerald , Veronique , Dames, Joanna F , Hawley, Greer L
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426058 , vital:72310 , xlink:href="https://hdl.handle.net/10520/ejc-soufor-v82-n4-a8"
- Description: The South African forestry industry covers approximately 1.3 million hectares and is dependent on exotic pine and eucalypt species. Nursery seedlings are not inoculated with ectomycorrhizal (ECM) fungi. This investigation assessed levels of naturally occurring ECM colonisation of Pinus patula seedlings from 10 different South African forestry nurseries using a grid line intersect method. Fungi from colonised roots were identified using morphological characteristics and Illumina sequencing. Colonisation of seedlings in production nurseries was low (2-21%). Morphologically, the ECM fungi Thelophora terrestris, Suillus sibiricus, and the genera Russula and Pseudotomentella were identified. Molecularly, the ECM fungi T. terrestris, Inocybe jacobi and the genus Sphaerosporella, as well as several other ECM-containing families were identified, along with many saprotrophic/ endophytic fungi belonging to genera such as Penicillium, Ramasonia and Talaromyces. As can be seen, a combination of both molecular and morphological identification techniques are needed as neither is able to give a full picture of the species present in isolation. This study reveals an initial insight into the root microbiome community associated with Pinus patula seedlings, which should be taken into account when inoculation with beneficial microbes is considered. It determined that natural ECM fungal root colonisation levels are very low throughout the South African nurseries investigated, indicating the need for ECM fungal inoculation, which can increase seedling growth, viability and resistance to pathogens.
- Full Text:
- Date Issued: 2020
Biological control potential of ectomycorrhizal fungi against Fusarium circinatum on Pinus patula seedlings
- Chartier FitzGerald, Veronique, Dames, Joanna F, Hawley, Grant L
- Authors: Chartier FitzGerald, Veronique , Dames, Joanna F , Hawley, Grant L
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/425960 , vital:72302 , xlink:href="https://doi.org/10.1080/09583157.2020.1771542"
- Description: The South Africa forestry industry, covering ∼1.3 million hectares, is dependent on exotic pine and Eucalyptus species. Nursery seedlings are not inoculated with ectomycorrhizal (ECM) fungi or other beneficial microbes. Fusarium circinatum is an economically important pathogen affecting seedling survival. The purpose of this investigation was to assess the effects of ectomycorrhizal fungal inoculation on Pinus patula seedling growth and resistance to the fungal pathogen F. circinatum. Explants from ECM basidiocarps, collected from Pinus stands, were plated onto MMN medium to obtain isolates that were then verified via DNA extraction and PCR amplification and sequencing of the ITS rDNA region. These isolates were identified as Boletus edulis f. reticulatus, Lactarius quieticolor, Suillus granulatus and an unknown Suillus species. P. patula growth in the presence of the pathogen F. circinatum was significantly increased and promoted by the L. quieticolor and Suillus isolates. Preventative inoculation of seedlings in the nursery using these isolates would ensure the production of stronger, healthier plants that would be more resistant to F. circinatum infection, increasing survival in the plantation.
- Full Text:
- Date Issued: 2020
- Authors: Chartier FitzGerald, Veronique , Dames, Joanna F , Hawley, Grant L
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/425960 , vital:72302 , xlink:href="https://doi.org/10.1080/09583157.2020.1771542"
- Description: The South Africa forestry industry, covering ∼1.3 million hectares, is dependent on exotic pine and Eucalyptus species. Nursery seedlings are not inoculated with ectomycorrhizal (ECM) fungi or other beneficial microbes. Fusarium circinatum is an economically important pathogen affecting seedling survival. The purpose of this investigation was to assess the effects of ectomycorrhizal fungal inoculation on Pinus patula seedling growth and resistance to the fungal pathogen F. circinatum. Explants from ECM basidiocarps, collected from Pinus stands, were plated onto MMN medium to obtain isolates that were then verified via DNA extraction and PCR amplification and sequencing of the ITS rDNA region. These isolates were identified as Boletus edulis f. reticulatus, Lactarius quieticolor, Suillus granulatus and an unknown Suillus species. P. patula growth in the presence of the pathogen F. circinatum was significantly increased and promoted by the L. quieticolor and Suillus isolates. Preventative inoculation of seedlings in the nursery using these isolates would ensure the production of stronger, healthier plants that would be more resistant to F. circinatum infection, increasing survival in the plantation.
- Full Text:
- Date Issued: 2020
An update on the indigenous vascular flora of sub-Antarctic Marion Island: taxonomic changes, sequences for DNA barcode loci, and genome size data
- Chau, John H, Mtsi, Nasipi I S, Münbergová, Zuzana, Greve, Michelle, le Roux, Peter C, Mairal, Mario, Le Roux, Johannes J, Dorrington, Rosemary A, van Vuuren, Bettine
- Authors: Chau, John H , Mtsi, Nasipi I S , Münbergová, Zuzana , Greve, Michelle , le Roux, Peter C , Mairal, Mario , Le Roux, Johannes J , Dorrington, Rosemary A , van Vuuren, Bettine
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/160344 , vital:40437 , https://0-doi.org.wam.seals.ac.za/10.1007/s00300-020-02747-7
- Description: The flora of sub-Antarctic Marion Island forms part of the unique South Indian Ocean Biogeographic Province, and is under threat from climate change and invasive species. Current information on the flora is necessary to rapidly identify and manage future changes. We conducted a literature search on the taxonomy of indigenous vascular plant species on Marion Island and found nomenclatural changes following taxonomic revisions for Austroblechnum penna-marina (Poir.) Gasper and V.A.O.Dittrich, Carex dikei (Nelmes) K.L.Wilson, Leptinella plumosa Hook.f., Notogrammitis crassior (Kirk) Parris, Phlegmariurus saururus (Lam.) B.Øllg., and Polypogon magellanicus (Lam.) Finot. Additionally, Ranunculus moseleyi Hook.f. was removed from our species checklist due to its long absence in floristic surveys, leaving 21 species in the indigenous vascular plant flora present on Marion Island. We also amplified and sequenced the universal plant barcoding loci rbcL and matK for 19 and 13 species, respectively, and found that ample interspecific genetic distance and minimal intraspecific genetic distance allowed for easy discrimination between species.
- Full Text:
- Date Issued: 2020
- Authors: Chau, John H , Mtsi, Nasipi I S , Münbergová, Zuzana , Greve, Michelle , le Roux, Peter C , Mairal, Mario , Le Roux, Johannes J , Dorrington, Rosemary A , van Vuuren, Bettine
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/160344 , vital:40437 , https://0-doi.org.wam.seals.ac.za/10.1007/s00300-020-02747-7
- Description: The flora of sub-Antarctic Marion Island forms part of the unique South Indian Ocean Biogeographic Province, and is under threat from climate change and invasive species. Current information on the flora is necessary to rapidly identify and manage future changes. We conducted a literature search on the taxonomy of indigenous vascular plant species on Marion Island and found nomenclatural changes following taxonomic revisions for Austroblechnum penna-marina (Poir.) Gasper and V.A.O.Dittrich, Carex dikei (Nelmes) K.L.Wilson, Leptinella plumosa Hook.f., Notogrammitis crassior (Kirk) Parris, Phlegmariurus saururus (Lam.) B.Øllg., and Polypogon magellanicus (Lam.) Finot. Additionally, Ranunculus moseleyi Hook.f. was removed from our species checklist due to its long absence in floristic surveys, leaving 21 species in the indigenous vascular plant flora present on Marion Island. We also amplified and sequenced the universal plant barcoding loci rbcL and matK for 19 and 13 species, respectively, and found that ample interspecific genetic distance and minimal intraspecific genetic distance allowed for easy discrimination between species.
- Full Text:
- Date Issued: 2020
Mineral Resources Governance and Socio-Economic Development in Zimbabwe
- Authors: Chawatama, Chrispen Tauya
- Date: 2020
- Subjects: Mines and mineral resources -- Zimbabwe Mining law --Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD(Dev)
- Identifier: http://hdl.handle.net/${Handle} , vital:42996
- Description: This study focused on investigating mineral resources governance (reflected in terms of three indicators of transparency, accountability and stakeholder inclusion) and its effect on socioeconomic development (in terms of three indicators of education, health and household incomes. Mineral resources can be a blessing and can lead to socioeconomic transformation of a country if they are managed transparently, accountably, inclusively equitably and sustainably. On the other hand, these subsoil capital assets can be a ‘curse’ and lead to poverty, conflicts amongst interest groups, elite capture, corruption and economic stagnation if they are not properly managed. Good governance of mineral resources seeks to ensure that the harnessing of mineral resources benefits the economy, enhances the quality of life and reduces poverty amongst citizens. The mining sector of Zimbabwe has risen to be the key economic sector in terms of its contribution to the GDP, FDI, fiscal revenue, exports and employment creation, particularly after the discovery of diamonds and more gold deposits in the country. However, in spite of the growth of the mining sector and its elevation to the mainstay of the economy, glaring dire socioeconomic conditions in terms of unemployment and high poverty levels, poor health, education and household incomes, leads one to question the way the country’s opulent mineral resources are being governed. The study used a mixed methods approach, through use of primary data (quantitative and qualitative data) and secondary data (archival data) as the basis for the collection as well as analysis of data. Complementarity of the research methods was achieved through use of data from household survey with 160 households in Mhondoro-Ngezi, Chegutu, Kwekwe and Shurugwi and in-depth interviews with officials of government ministries; of Finance and Economic Development, Health and Childcare, Primary and viii Secondary Education, local councillors, CSOs; ZELA and ZIMCODD, Traditional chiefs and ZASMC. The study established that mining growth is contributing somewhat to socio-economic development through employment creation, corporate social responsibility, CSOTs, ESPOs, taxation and royalties, but broad-based development has not taken place in the four districts. The study proposes a holistic mineral resources governance and socioeconomic development framework. The study recommends the Repeal of MMA and gazetting of a more comprehensive legal framework, implementation of constitutional provisions on transparency, accountability and stakeholder inclusion, adoption of free online tools for mineral processes disclosure, consolidation of the mining fiscal regime and so on.
- Full Text:
- Date Issued: 2020
- Authors: Chawatama, Chrispen Tauya
- Date: 2020
- Subjects: Mines and mineral resources -- Zimbabwe Mining law --Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD(Dev)
- Identifier: http://hdl.handle.net/${Handle} , vital:42996
- Description: This study focused on investigating mineral resources governance (reflected in terms of three indicators of transparency, accountability and stakeholder inclusion) and its effect on socioeconomic development (in terms of three indicators of education, health and household incomes. Mineral resources can be a blessing and can lead to socioeconomic transformation of a country if they are managed transparently, accountably, inclusively equitably and sustainably. On the other hand, these subsoil capital assets can be a ‘curse’ and lead to poverty, conflicts amongst interest groups, elite capture, corruption and economic stagnation if they are not properly managed. Good governance of mineral resources seeks to ensure that the harnessing of mineral resources benefits the economy, enhances the quality of life and reduces poverty amongst citizens. The mining sector of Zimbabwe has risen to be the key economic sector in terms of its contribution to the GDP, FDI, fiscal revenue, exports and employment creation, particularly after the discovery of diamonds and more gold deposits in the country. However, in spite of the growth of the mining sector and its elevation to the mainstay of the economy, glaring dire socioeconomic conditions in terms of unemployment and high poverty levels, poor health, education and household incomes, leads one to question the way the country’s opulent mineral resources are being governed. The study used a mixed methods approach, through use of primary data (quantitative and qualitative data) and secondary data (archival data) as the basis for the collection as well as analysis of data. Complementarity of the research methods was achieved through use of data from household survey with 160 households in Mhondoro-Ngezi, Chegutu, Kwekwe and Shurugwi and in-depth interviews with officials of government ministries; of Finance and Economic Development, Health and Childcare, Primary and viii Secondary Education, local councillors, CSOs; ZELA and ZIMCODD, Traditional chiefs and ZASMC. The study established that mining growth is contributing somewhat to socio-economic development through employment creation, corporate social responsibility, CSOTs, ESPOs, taxation and royalties, but broad-based development has not taken place in the four districts. The study proposes a holistic mineral resources governance and socioeconomic development framework. The study recommends the Repeal of MMA and gazetting of a more comprehensive legal framework, implementation of constitutional provisions on transparency, accountability and stakeholder inclusion, adoption of free online tools for mineral processes disclosure, consolidation of the mining fiscal regime and so on.
- Full Text:
- Date Issued: 2020
A 150 MHz all sky survey with the Precision Array to Probe the Epoch of Reionization
- Authors: Chege, James Kariuki
- Date: 2020
- Subjects: Epoch of reionization -- Research , Astronomy -- Observations , Radio interferometers
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/117733 , vital:34556
- Description: The Precision Array to Probe the Epoch of Reionization (PAPER) was built to measure the redshifted 21 cm line of hydrogen from cosmic reionization. Such low frequency observations promise to be the best means of understanding the cosmic dawn; when the first galaxies in the universe formed, and also the Epoch of Reionization; when the intergalactic medium changed from neutral to ionized. The major challenges to these observations is the presence of astrophysical foregrounds that are much brighter than the cosmological signal. Here, I present an all-sky survey at 150 MHz obtained from the analysis of 300 hours of PAPER observations. Particular focus is given to the calibration and imaging techniques that need to deal with the wide field of view of a non-tracking instrument. The survey covers ~ 7000 square degrees of the southern sky. From a sky area of 4400 square degrees out of the total survey area, I extract a catalogue of sources brighter than 4 Jy whose accuracy was tested against the published GLEAM catalogue, leading to a fractional difference rms better than 20%. The catalogue provides an all-sky accurate model of the extragalactic foreground to be used for the calibration of future Epoch of Reionization observations and to be subtracted from the PAPER observations themselves in order to mitigate the foreground contamination.
- Full Text:
- Date Issued: 2020
- Authors: Chege, James Kariuki
- Date: 2020
- Subjects: Epoch of reionization -- Research , Astronomy -- Observations , Radio interferometers
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/117733 , vital:34556
- Description: The Precision Array to Probe the Epoch of Reionization (PAPER) was built to measure the redshifted 21 cm line of hydrogen from cosmic reionization. Such low frequency observations promise to be the best means of understanding the cosmic dawn; when the first galaxies in the universe formed, and also the Epoch of Reionization; when the intergalactic medium changed from neutral to ionized. The major challenges to these observations is the presence of astrophysical foregrounds that are much brighter than the cosmological signal. Here, I present an all-sky survey at 150 MHz obtained from the analysis of 300 hours of PAPER observations. Particular focus is given to the calibration and imaging techniques that need to deal with the wide field of view of a non-tracking instrument. The survey covers ~ 7000 square degrees of the southern sky. From a sky area of 4400 square degrees out of the total survey area, I extract a catalogue of sources brighter than 4 Jy whose accuracy was tested against the published GLEAM catalogue, leading to a fractional difference rms better than 20%. The catalogue provides an all-sky accurate model of the extragalactic foreground to be used for the calibration of future Epoch of Reionization observations and to be subtracted from the PAPER observations themselves in order to mitigate the foreground contamination.
- Full Text:
- Date Issued: 2020
Analysis of the existence of the Phillips curve, Okun’s law and Taylor rule in the Zambian economy
- Authors: Chella, Siame Nampasa
- Date: 2020
- Subjects: Unemployment -- Effect of inflation -- Mathematical models --Zambia
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10948/49783 , vital:41800
- Description: The objective for this study was to explore the relationship between inflation and growth with an understanding of the effects of unemployment on growth. The primary objective of this paper was to investigate the existence of Phillips Curve, Okun’s Law, and Taylor Rule in Zambia on the basis that Zambia is a youthful economy, with a growing population, which is expected to temper with unemployment rates, as an increase in the supply of labour might be too high for the demand for jobs available. To be specific, the study aims at determining the relationship between inflation and growth and seeks to understand what policy measures have been undertaken to curb inflation and reduce unemployment in Zambia. To achieve this, a quantitative research was undertaken using the ARDL cointegration model in conjunction with sensitivity tests to cater for structural changes in the economy with 2007 standing as the break point, as well as paying attention to the fact that different policy regimes employed during the course of the data covered, that being, 1996 to 2017, would affect that rates of unemployment, inflation and growth of the country, across period under review. The study revealed that Zambia faces a Hybrid New Keynesian Phillips Curve during the period under study which is dominated by a mixture of both back-ward and forward-looking aspects of inflation. This specifically, paints the effects of inflation persistence as well future expectations of inflation on growth. Further, a cointegration relationship was established between unemployment and output, while Taylor principles were found not to apply to the Zambian economy, which have proved in other economies to be foundation blocks for good economic growth and as such significant to both fiscal and monetary policy authorities of the economy. The researcher therefore recommends that Zambian policy makers, that is, both the fiscal and the monetary authorities, work together in order to attain minimal and optimal levels of inflation to help achieve a conducive economic environment for the country.
- Full Text:
- Date Issued: 2020
- Authors: Chella, Siame Nampasa
- Date: 2020
- Subjects: Unemployment -- Effect of inflation -- Mathematical models --Zambia
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10948/49783 , vital:41800
- Description: The objective for this study was to explore the relationship between inflation and growth with an understanding of the effects of unemployment on growth. The primary objective of this paper was to investigate the existence of Phillips Curve, Okun’s Law, and Taylor Rule in Zambia on the basis that Zambia is a youthful economy, with a growing population, which is expected to temper with unemployment rates, as an increase in the supply of labour might be too high for the demand for jobs available. To be specific, the study aims at determining the relationship between inflation and growth and seeks to understand what policy measures have been undertaken to curb inflation and reduce unemployment in Zambia. To achieve this, a quantitative research was undertaken using the ARDL cointegration model in conjunction with sensitivity tests to cater for structural changes in the economy with 2007 standing as the break point, as well as paying attention to the fact that different policy regimes employed during the course of the data covered, that being, 1996 to 2017, would affect that rates of unemployment, inflation and growth of the country, across period under review. The study revealed that Zambia faces a Hybrid New Keynesian Phillips Curve during the period under study which is dominated by a mixture of both back-ward and forward-looking aspects of inflation. This specifically, paints the effects of inflation persistence as well future expectations of inflation on growth. Further, a cointegration relationship was established between unemployment and output, while Taylor principles were found not to apply to the Zambian economy, which have proved in other economies to be foundation blocks for good economic growth and as such significant to both fiscal and monetary policy authorities of the economy. The researcher therefore recommends that Zambian policy makers, that is, both the fiscal and the monetary authorities, work together in order to attain minimal and optimal levels of inflation to help achieve a conducive economic environment for the country.
- Full Text:
- Date Issued: 2020
Management competencies of clinical and hospital managers in the eastern cape department of health: implications for further management training
- Authors: Chetty, Urvani
- Date: 2020
- Subjects: Medical personnel
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/47509 , vital:40130
- Description: Healthcare has been identified as a basic need and one of the key economic drivers in South Africa (Pravin Gordhan, 2017). With the majority of South Africans reliant on the public health sector for the management, the prevention and cure of all their healthcare issues and needs come the dire requirement of exceptional skills from healthcare professionals. Hospital and clinical managers play the dual role of clinician and manager, often without proper management training. With the impending introduction of the National Health Insurance (NHI) and ever-challenging constraints of medico-legal litigation on healthcare, it is imperative that healthcare professionals are adequately equipped with the core management competencies. The aim of the study is to identify management competencies of Clinical and Hospital managers and establish an implication/indication for further management training. This study used competencies identified in healthcare management courses currently offered in South Africa in conjunction with literature reviewed. A sample population of Clinical and Hospital managers in the public sector of the Eastern Cape was used using a non-random purposive/judgement probability sampling technique–the “snowball” sampling technique. The questionnaire link (Questionpro) was distributed to all respondents via email and WhatsApp distribution followed from the Eastern Cape Department of Health Head Office to the Chief Executive Officers of hospitals in the Eastern Cape and the Human Resources Director of the Eastern Cape Department of Health. The online link was made available for completion; thereafter data was collated and analysed using the STATISTICA programme. Based on a literature review, the theoretical model proposed six core competencies-leadership, risk management, financial management, corporate governance and ethics, people/human resources management and quality and evidence-based management. Of the six competencies, Clinical and Hospital Managers exhibited Leadership, Corporate Governance and Ethics and Quality and Evidence-based Management in high levels. The qualitative analysis demonstrated respondents’ intentions to study further, often in management fields and shared a unanimous need for management training for better job efficacy and performance. The researcher has made recommendations to aid in improving management skills as well as areas for further research such as short courses and mentorship programmes and further comparative studies between the private and public sector. The study concluded that management competencies are significant for Clinical and Hospital Managers and should be addressed in the future to aid in better clinical outcomes.
- Full Text:
- Date Issued: 2020
- Authors: Chetty, Urvani
- Date: 2020
- Subjects: Medical personnel
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/47509 , vital:40130
- Description: Healthcare has been identified as a basic need and one of the key economic drivers in South Africa (Pravin Gordhan, 2017). With the majority of South Africans reliant on the public health sector for the management, the prevention and cure of all their healthcare issues and needs come the dire requirement of exceptional skills from healthcare professionals. Hospital and clinical managers play the dual role of clinician and manager, often without proper management training. With the impending introduction of the National Health Insurance (NHI) and ever-challenging constraints of medico-legal litigation on healthcare, it is imperative that healthcare professionals are adequately equipped with the core management competencies. The aim of the study is to identify management competencies of Clinical and Hospital managers and establish an implication/indication for further management training. This study used competencies identified in healthcare management courses currently offered in South Africa in conjunction with literature reviewed. A sample population of Clinical and Hospital managers in the public sector of the Eastern Cape was used using a non-random purposive/judgement probability sampling technique–the “snowball” sampling technique. The questionnaire link (Questionpro) was distributed to all respondents via email and WhatsApp distribution followed from the Eastern Cape Department of Health Head Office to the Chief Executive Officers of hospitals in the Eastern Cape and the Human Resources Director of the Eastern Cape Department of Health. The online link was made available for completion; thereafter data was collated and analysed using the STATISTICA programme. Based on a literature review, the theoretical model proposed six core competencies-leadership, risk management, financial management, corporate governance and ethics, people/human resources management and quality and evidence-based management. Of the six competencies, Clinical and Hospital Managers exhibited Leadership, Corporate Governance and Ethics and Quality and Evidence-based Management in high levels. The qualitative analysis demonstrated respondents’ intentions to study further, often in management fields and shared a unanimous need for management training for better job efficacy and performance. The researcher has made recommendations to aid in improving management skills as well as areas for further research such as short courses and mentorship programmes and further comparative studies between the private and public sector. The study concluded that management competencies are significant for Clinical and Hospital Managers and should be addressed in the future to aid in better clinical outcomes.
- Full Text:
- Date Issued: 2020
Fraud tolerance level as a predictor of insurance claims behavior: A South African Study
- Authors: Chetty,Moonsamy Perumal
- Date: 2020
- Subjects: Insurance fraud Fraud -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD(Criminology)
- Identifier: http://hdl.handle.net/10353/17964 , vital:41999
- Description: The insurance sector as a foundation which other sectors depend on is a critical cornerstone of a well-functioning society. An insurer’s strength exists in its ability to foresee, assess, price and mitigate current and emerging risks. Despite the value that insurance brings to maintaining and sustaining society there is large scale abuse of the various insurance products on offer. The abuse is predominately committed through the submitting of either false or inflated claims which negatively impacts the entire insurance value chain from underwriting to claims processes. Insurance claims fraud is classified as opportunistic or organised. Opportunistic claims fraud consists of claims inflation or claims padding for a genuine loss while organised claims fraud involves the lodging a claim for a loss that did not occur and usually involves staging of incidents. Opportunistic fraud is the most common type of fraud experienced by insurers and presents the greatest challenge to the insurance industry. While there are challenges in accurately determining the true costs of insurance fraud; there is consensus that the costs are significant. In response to incidents of insurance fraud insurers have implemented various measures to curb fraud; these measures range from the establishment of insurance crime bureaus, creation of internal investigation teams and the employment of technology as early warning systems. These measures although useful have not been able to be very effective as insurance fraud still continues to rise. Studies indicate that consumer attitudes towards insurance fraud play an important role which must be considered when developing fraud prevention strategies. Tolerance has been identified as an important factor which influence consumer v attitudes towards insurance fraud. Previous studies found that factors such as high insurance premiums, excess payments, consumer relationship with insurers, consumer’s previous claims experience and societal acceptability of insurance fraud played a role in shaping a consumer’s tolerance level. This study was undertaken to explore the role that policyholder tolerance has on predicting claims behaviour in the South African insurance market. The study also aimed at identifying reasons which motivated policyholder’s to commit and deter them from committing insurance fraud. A further aim was to identify the common types of insurance fraud and to measure policyholders’ perceptions towards their primary insurer, the insurance industry, brokers and insurance assessors. The fraud triangle and the theory of planned behaviour were used as theories in support of this study. Primary data for this study was gather through an online self-administered questionnaire and the sample population consisted of policyholders within the shortterm insurance market. A total of 560 completed valid questionnaires were received and analysed. The study shows that respondents have low levels of tolerance for insurance fraud. Results indicated that financial pressure, greed, financial benefit and opportunity were reasons why policyholders’ committed insurance fraud in SA. Factors which deterred policyholders from committing insurance fraud included consumer integrity and honesty, fear of being caught and prosecuted and fairness and value for money. vi Respondents indicated that inflated claims were more prevalent than false claims and it was easier to submit an inflated claim than a false claim. Regarding perceptions the study shows that respondents have a more positive view of their own primary insurer than the insurance industry in general, brokers and insurance assessors. Lastly, the research identified five factors that significantly explain levels of short-term insurance fraud tolerance, namely 'Unfairness/injustice', “Have policyholders’ best interest at heart”, 'Industry relations', ‘Opportunity’ and 'Morality'. The findings of this study could be useful to insurers when developing consumer education and awareness programmes. There exists opportunities for future research regarding several aspects of insurance fraud which was not dealt with in this study.
- Full Text:
- Date Issued: 2020
- Authors: Chetty,Moonsamy Perumal
- Date: 2020
- Subjects: Insurance fraud Fraud -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD(Criminology)
- Identifier: http://hdl.handle.net/10353/17964 , vital:41999
- Description: The insurance sector as a foundation which other sectors depend on is a critical cornerstone of a well-functioning society. An insurer’s strength exists in its ability to foresee, assess, price and mitigate current and emerging risks. Despite the value that insurance brings to maintaining and sustaining society there is large scale abuse of the various insurance products on offer. The abuse is predominately committed through the submitting of either false or inflated claims which negatively impacts the entire insurance value chain from underwriting to claims processes. Insurance claims fraud is classified as opportunistic or organised. Opportunistic claims fraud consists of claims inflation or claims padding for a genuine loss while organised claims fraud involves the lodging a claim for a loss that did not occur and usually involves staging of incidents. Opportunistic fraud is the most common type of fraud experienced by insurers and presents the greatest challenge to the insurance industry. While there are challenges in accurately determining the true costs of insurance fraud; there is consensus that the costs are significant. In response to incidents of insurance fraud insurers have implemented various measures to curb fraud; these measures range from the establishment of insurance crime bureaus, creation of internal investigation teams and the employment of technology as early warning systems. These measures although useful have not been able to be very effective as insurance fraud still continues to rise. Studies indicate that consumer attitudes towards insurance fraud play an important role which must be considered when developing fraud prevention strategies. Tolerance has been identified as an important factor which influence consumer v attitudes towards insurance fraud. Previous studies found that factors such as high insurance premiums, excess payments, consumer relationship with insurers, consumer’s previous claims experience and societal acceptability of insurance fraud played a role in shaping a consumer’s tolerance level. This study was undertaken to explore the role that policyholder tolerance has on predicting claims behaviour in the South African insurance market. The study also aimed at identifying reasons which motivated policyholder’s to commit and deter them from committing insurance fraud. A further aim was to identify the common types of insurance fraud and to measure policyholders’ perceptions towards their primary insurer, the insurance industry, brokers and insurance assessors. The fraud triangle and the theory of planned behaviour were used as theories in support of this study. Primary data for this study was gather through an online self-administered questionnaire and the sample population consisted of policyholders within the shortterm insurance market. A total of 560 completed valid questionnaires were received and analysed. The study shows that respondents have low levels of tolerance for insurance fraud. Results indicated that financial pressure, greed, financial benefit and opportunity were reasons why policyholders’ committed insurance fraud in SA. Factors which deterred policyholders from committing insurance fraud included consumer integrity and honesty, fear of being caught and prosecuted and fairness and value for money. vi Respondents indicated that inflated claims were more prevalent than false claims and it was easier to submit an inflated claim than a false claim. Regarding perceptions the study shows that respondents have a more positive view of their own primary insurer than the insurance industry in general, brokers and insurance assessors. Lastly, the research identified five factors that significantly explain levels of short-term insurance fraud tolerance, namely 'Unfairness/injustice', “Have policyholders’ best interest at heart”, 'Industry relations', ‘Opportunity’ and 'Morality'. The findings of this study could be useful to insurers when developing consumer education and awareness programmes. There exists opportunities for future research regarding several aspects of insurance fraud which was not dealt with in this study.
- Full Text:
- Date Issued: 2020
The current nature of intra-regional trade in the proposed tripartite free trade area
- Authors: Chibuta, Chisengele
- Date: 2020
- Subjects: Customs unions -- Africa, Southern -- Economic integration , Africa, Southern -- Economic policy , Africa, Southern -- Economic integration , Africa, Southern -- Economic conditions , Tripartite Free Trade Area , Free trade -- Africa, Southern
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/146744 , vital:38553
- Description: This thesis examines and analyses the current nature of intra-regional trade between member states of the proposed Tripartite Free Trade Area in order to contribute to an understanding of the potential for intra-regional trade within the region to increase. Trade Complementarity Indexes were used to determine how well the structures of the three founding blocs’ major imports and exports match. The results show that there is a high degree of trade complementarity in the trade of the top 5 major products traded between the regional groups. With the proposed TFTA in place, high trade complementarity could lead to increased trade between the regional groups. Trade Intensity Indexes were used to determine how intensively the three founding blocs trade with one another. Results from the indexes help determine the extent to which the blocs currently view each other as important trading partners and the implications of this for the proposed TFTA. Results show that EAC and SADC as well as EAC and COMESA viewed each other as significant trading partners while SADC and COMESA did not for the majority of the years from 2001 to 2018. With the TFTA in place, intra-regional trade could be strengthened among the members who currently trade intensively because tariffs between them would be progressively eliminated as required by the TFTA Agreement. Revealed Comparative Advantage Indexes were used to gain insights on whether member states have any comparative advantage in their top 5 exports. Results from the indexes were used to determine whether member states have comparative advantage in similar or dissimilar major exports and the implications of this for the proposed TFTA. Results show that member states have revealed comparative advantage in similar products and these products present opportunities for joint-production among member states as well as sectors for product development once the proposed TFTA is in place. Revealed Trade Barrier Indexes were used to gain insights into the extent of ease of market access into each regional bloc’s market. Results from the indexes indicate whether major products imported from each other receive possibly discriminatory or preferential treatment. The results indicate that the majority of the top 5 imports sourced from each region receive preferential treatment. This indicates that there is ease of market access for the top 5 imports sourced from each other and this could promote increased intra-regional trade among member states in these product categories because tariff and non-tariff barriers to trade will be progressively eliminated once the TFTA is in place.
- Full Text:
- Date Issued: 2020
- Authors: Chibuta, Chisengele
- Date: 2020
- Subjects: Customs unions -- Africa, Southern -- Economic integration , Africa, Southern -- Economic policy , Africa, Southern -- Economic integration , Africa, Southern -- Economic conditions , Tripartite Free Trade Area , Free trade -- Africa, Southern
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/146744 , vital:38553
- Description: This thesis examines and analyses the current nature of intra-regional trade between member states of the proposed Tripartite Free Trade Area in order to contribute to an understanding of the potential for intra-regional trade within the region to increase. Trade Complementarity Indexes were used to determine how well the structures of the three founding blocs’ major imports and exports match. The results show that there is a high degree of trade complementarity in the trade of the top 5 major products traded between the regional groups. With the proposed TFTA in place, high trade complementarity could lead to increased trade between the regional groups. Trade Intensity Indexes were used to determine how intensively the three founding blocs trade with one another. Results from the indexes help determine the extent to which the blocs currently view each other as important trading partners and the implications of this for the proposed TFTA. Results show that EAC and SADC as well as EAC and COMESA viewed each other as significant trading partners while SADC and COMESA did not for the majority of the years from 2001 to 2018. With the TFTA in place, intra-regional trade could be strengthened among the members who currently trade intensively because tariffs between them would be progressively eliminated as required by the TFTA Agreement. Revealed Comparative Advantage Indexes were used to gain insights on whether member states have any comparative advantage in their top 5 exports. Results from the indexes were used to determine whether member states have comparative advantage in similar or dissimilar major exports and the implications of this for the proposed TFTA. Results show that member states have revealed comparative advantage in similar products and these products present opportunities for joint-production among member states as well as sectors for product development once the proposed TFTA is in place. Revealed Trade Barrier Indexes were used to gain insights into the extent of ease of market access into each regional bloc’s market. Results from the indexes indicate whether major products imported from each other receive possibly discriminatory or preferential treatment. The results indicate that the majority of the top 5 imports sourced from each region receive preferential treatment. This indicates that there is ease of market access for the top 5 imports sourced from each other and this could promote increased intra-regional trade among member states in these product categories because tariff and non-tariff barriers to trade will be progressively eliminated once the TFTA is in place.
- Full Text:
- Date Issued: 2020
Reliving it through pen
- Authors: Chidi, Tsosheletso
- Date: 2020
- Subjects: South African fiction (English) , Northern Sotho poetry
- Language: English , Northern Sotho
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/163566 , vital:41049
- Description: This document consists of two parts: PART A: English Half Thesis (Creative Work) PART B: Dual Language Portfolio (Sepedi and English). This thesis focuses on witnessing the trauma of rape, inability to move on, denial and attempt to forget, it draws attention also to emotional abuse in a place called home, death and place. My work is influenced by Carolyn Fourche’s anthology, Against Forgetting: Poetry of Witness, Adam Bradley and Andrew Dubois’s The Anthology of the Rap, as well as Lesego Rampolokeng poem “Welcome to New Consciousness”.
- Full Text:
- Date Issued: 2020
- Authors: Chidi, Tsosheletso
- Date: 2020
- Subjects: South African fiction (English) , Northern Sotho poetry
- Language: English , Northern Sotho
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/163566 , vital:41049
- Description: This document consists of two parts: PART A: English Half Thesis (Creative Work) PART B: Dual Language Portfolio (Sepedi and English). This thesis focuses on witnessing the trauma of rape, inability to move on, denial and attempt to forget, it draws attention also to emotional abuse in a place called home, death and place. My work is influenced by Carolyn Fourche’s anthology, Against Forgetting: Poetry of Witness, Adam Bradley and Andrew Dubois’s The Anthology of the Rap, as well as Lesego Rampolokeng poem “Welcome to New Consciousness”.
- Full Text:
- Date Issued: 2020