Probing the binding sites of novel 2-substituted imidazole-4,5-dicarboxylic acids : Towards new imidazole-based drugs
- Authors: Clark, Candyce Raine
- Date: 2021
- Subjects: Heterocyclic compounds Coordination compounds
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50848 , vital:42957
- Description: A series of benzimidazole and imidazole-4,5-dicarboxylic acids were prepared using known and adapted protocols. Novel ligands synthesised in this study include 2-tert-butyl-benzimidazole, 2-tert-butyl-imidazole-4,5-dicarboxylic acid, an intermediate in the synthesis of 1,2- bis(2-benzimidazyl)-1,2,-dihydroxyethane and 2-(2-hydroxyphenyl)-benzimidazole with a salicylic acid co-crystallisate. All ligands prepared were reacted with metal salt solutions in order to prepare metal coordination compounds. Complexes with Cu(II), Ag(I), Mn(II), Ni(II) and Cd(II) ions and 2-phenyl-imidazole-4,5-dicarboxylic acid were prepared, as well as Cu(II) and Mn(II) with 2-trifluoro-methyl-imidazole-4,5-dicarboxylic acid and Cu(II) ions with 2-(2- hydroxyphenyl)-benzimidazole. The ligands and complexes were characterised by means of single-crystal X-ray diffraction studies, NMR analysis, UV spectrophotometric analysis and IR spectroscopy. DFT studies were carried out for selected ligands in order to provide theoretical values for comparison. Antimicrobial studies were performed on some of the ligands and complexes and these results show promise for the future development of new imidazole-based drugs.
- Full Text:
- Date Issued: 2021
- Authors: Clark, Candyce Raine
- Date: 2021
- Subjects: Heterocyclic compounds Coordination compounds
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50848 , vital:42957
- Description: A series of benzimidazole and imidazole-4,5-dicarboxylic acids were prepared using known and adapted protocols. Novel ligands synthesised in this study include 2-tert-butyl-benzimidazole, 2-tert-butyl-imidazole-4,5-dicarboxylic acid, an intermediate in the synthesis of 1,2- bis(2-benzimidazyl)-1,2,-dihydroxyethane and 2-(2-hydroxyphenyl)-benzimidazole with a salicylic acid co-crystallisate. All ligands prepared were reacted with metal salt solutions in order to prepare metal coordination compounds. Complexes with Cu(II), Ag(I), Mn(II), Ni(II) and Cd(II) ions and 2-phenyl-imidazole-4,5-dicarboxylic acid were prepared, as well as Cu(II) and Mn(II) with 2-trifluoro-methyl-imidazole-4,5-dicarboxylic acid and Cu(II) ions with 2-(2- hydroxyphenyl)-benzimidazole. The ligands and complexes were characterised by means of single-crystal X-ray diffraction studies, NMR analysis, UV spectrophotometric analysis and IR spectroscopy. DFT studies were carried out for selected ligands in order to provide theoretical values for comparison. Antimicrobial studies were performed on some of the ligands and complexes and these results show promise for the future development of new imidazole-based drugs.
- Full Text:
- Date Issued: 2021
The application of human factors and ergonomics (HFE) to community-sport organisations in resource scarce contexts: a case study of grassroots football in Makana, Eastern Cape
- Authors: Bennett, Ryan
- Date: 2021
- Subjects: Makana Local Football Association (South Africa) , Human engineering , Soccer teams -- South Africa -- Makhanda -- Management , Soccer -- Management -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/172412 , vital:42198 , 10.21504/10962/172412
- Description: Background: Modern Human Factors and Ergonomics (HFE) focuses on the optimisation of complex socio-technical systems and has been challenged to contribute to broader societal issues. An example is within grassroots football organisations in resource-scarce areas such as Makana, South Africa. Through embedded participatory approaches, the research problem was co-constructed: To investigate the socio-technical system of the Makana Local Football Association (LFA). Method: A useful complex system modelling tool is that of Cognitive Work Analysis (CWA), with its 5 phases used to identify constraints and affordances. Three perspectives were adopted for the application of an adapted (to suit participant characteristics) CWA to the Makana LFA: 1) how work is prescribed by the governing body SAFA, 2) how subject matter experts (SME) disclose its current functioning, and 3) how SMEs imagine it could function. Five SMEs attended 12 three-hour workshops to complete the latter two perspectives. Results: The composite work domain analysis between work as prescribed and work as disclosed identified significant mismatches between how policymakers envision the system and how SMEs report its functioning. Key differences in perspectives included the fundamental purpose of the Makana LFA, while only four of 22 functions operate within the Makana LFA. Participants also identified key affordances for the LFA such as reorientation as a community sports organisation. Discussion: Comparison between perspectives indicated four mismatches. 1) SAFA views the LFA as the foundation of the talent identification and development infrastructure of South African football. SMEs view it as a community centred organisation. 2) A lack of human capacity is evident at the community level of Makana football. 3) Funding and assets are absent at this grassroots level. 4) The LFA relies on other stakeholders, but these relationships are not formalised. Policymakers, therefore, have a lack of knowledge of the contextual challenges faced by LFA administrators. It is recommended that SAFA view the LFA as a community sport organisation, focusing on improving human capacity, increasing funding, and formalising stakeholder networks. Furthermore, conceptual models from CWA provide explicit socio-technical system redesign recommendations. Conclusion: Large mismatches between the organising body SAFA and the actual functioning of the LFA significantly hinder the effective management and running of football at a grassroots level in resource-scarce contexts in South Africa. The perspectives approach to CWA was useful in elucidating the constraints and affordances of the Makana LFA socio-technical system and informing redesign opportunities. Systems HFE methodology is therefore well placed to contribute to broader societal issues within resources scarce contexts such as football in Makana. Furthermore, the philosophical underpinnings of systems based HFE were successful in the development of sustainable participatory research within the South African grassroots football context.
- Full Text:
- Date Issued: 2021
- Authors: Bennett, Ryan
- Date: 2021
- Subjects: Makana Local Football Association (South Africa) , Human engineering , Soccer teams -- South Africa -- Makhanda -- Management , Soccer -- Management -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/172412 , vital:42198 , 10.21504/10962/172412
- Description: Background: Modern Human Factors and Ergonomics (HFE) focuses on the optimisation of complex socio-technical systems and has been challenged to contribute to broader societal issues. An example is within grassroots football organisations in resource-scarce areas such as Makana, South Africa. Through embedded participatory approaches, the research problem was co-constructed: To investigate the socio-technical system of the Makana Local Football Association (LFA). Method: A useful complex system modelling tool is that of Cognitive Work Analysis (CWA), with its 5 phases used to identify constraints and affordances. Three perspectives were adopted for the application of an adapted (to suit participant characteristics) CWA to the Makana LFA: 1) how work is prescribed by the governing body SAFA, 2) how subject matter experts (SME) disclose its current functioning, and 3) how SMEs imagine it could function. Five SMEs attended 12 three-hour workshops to complete the latter two perspectives. Results: The composite work domain analysis between work as prescribed and work as disclosed identified significant mismatches between how policymakers envision the system and how SMEs report its functioning. Key differences in perspectives included the fundamental purpose of the Makana LFA, while only four of 22 functions operate within the Makana LFA. Participants also identified key affordances for the LFA such as reorientation as a community sports organisation. Discussion: Comparison between perspectives indicated four mismatches. 1) SAFA views the LFA as the foundation of the talent identification and development infrastructure of South African football. SMEs view it as a community centred organisation. 2) A lack of human capacity is evident at the community level of Makana football. 3) Funding and assets are absent at this grassroots level. 4) The LFA relies on other stakeholders, but these relationships are not formalised. Policymakers, therefore, have a lack of knowledge of the contextual challenges faced by LFA administrators. It is recommended that SAFA view the LFA as a community sport organisation, focusing on improving human capacity, increasing funding, and formalising stakeholder networks. Furthermore, conceptual models from CWA provide explicit socio-technical system redesign recommendations. Conclusion: Large mismatches between the organising body SAFA and the actual functioning of the LFA significantly hinder the effective management and running of football at a grassroots level in resource-scarce contexts in South Africa. The perspectives approach to CWA was useful in elucidating the constraints and affordances of the Makana LFA socio-technical system and informing redesign opportunities. Systems HFE methodology is therefore well placed to contribute to broader societal issues within resources scarce contexts such as football in Makana. Furthermore, the philosophical underpinnings of systems based HFE were successful in the development of sustainable participatory research within the South African grassroots football context.
- Full Text:
- Date Issued: 2021
The electrocatalytic response of metallophthalocyanines when clicked to electrodes and to nanomaterials
- Authors: Mpeta, Lekhetho Simon
- Date: 2021
- Subjects: Phthalocyanines , Nanostructured materials , Electrocatalysis , Nanoparticles , Environmental chemistry , Electrodes , Organic wastes -- Purification
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/172191 , vital:42174 , 10.21504/10962/172191
- Description: Conjugates of nanomaterials and metallophthalocyanines (MPcs) have been prepared and their electrocatalytic activity studied. The prepared nanomaterials are zinc oxide and silver nanoparticles, reduced graphene oxide nanosheets and semiconductor quantum dots. The MPcs used in this work are cobalt (II) (1a), manganese(III) (1b) and iron (II) (1c) 2,9(10),16(17),23(24)- tetrakis 4-((4-ethynylbenzyl) oxy) phthalocyaninato, 2,9(10),16(17),23(24)- tetrakis(5-pentyn-oxy) cobalt (II) phthalocyaninato (2), 9(10),16(17),23(24)- tris-[4-tert-butylphenoxy)-2- (4-ethylbezyl-oxy) cobalt (II) phthalocyaninato (3), 9(10),16(17),23(24)- tris-[4-tertbutylphenoxy)-2-(pent-4yn-yloxy)] cobalt (II) phthalocyaninato (4), cobalt (II) (5a) and manganese (III) (5b) 2,9(10),16(17),23(24)- tetrakis [4-(4-(5-chloro-1H-benzo [d]imidazol-2-yl)phenoxy] phthalocyaninato and 9(10),16(17),23(24)- tris tert butyl phenoxy- 2- [4-(4-(5-chloro-1H-benzo[d]imidazole-2-yl)phenoxy] cobalt (II) phthalocyaninato (6). Some of these MPcs (1a, 3 and 4) were directly clicked on azide grafted electrode, while some (1b, 1c, 2, 5a and 5b) were clicked to azide functionalised nanomaterials and then drop-dried on the electrodes. One phthalocyanine (5b) was drop-dried on the electrode then silver nanoparticles were electrodeposited on it taking advantage of metal-N bond. Scanning electrochemical microscopy, voltammetry, chronoamperometry, electrochemical impedance spectroscopy are among electrochemical methods used to characterise modified electrodes. Transmission electron microscopy, X-ray photoelectron spectroscopy, Xray diffractometry, Raman spectroscopy and infrared spectroscopy were employed to study surface functionalities, morphology and topography of the nanomaterials and complexes. Electrocatalytic activity of the developed materials were studied towards oxidation of 2-mercaptoethanol, hydrazine and hydrogen peroxide while the reduction study was based on oxygen and hydrogen peroxide. In general, the conjugates displayed superior catalytic activity when compared to individual materials. Complex 2 alone and when conjugated to zinc oxide nanoparticles were studied for their nonlinear optical behaviour. And the same materials were explored for their hydrazine detection capability. The aim of this study was to develop sensitive, selective and affordable sensors for selected organic waste pollutants. Conjugates were found to achieve the aim of the study compared to when individual materials were employed.
- Full Text:
- Date Issued: 2021
- Authors: Mpeta, Lekhetho Simon
- Date: 2021
- Subjects: Phthalocyanines , Nanostructured materials , Electrocatalysis , Nanoparticles , Environmental chemistry , Electrodes , Organic wastes -- Purification
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/172191 , vital:42174 , 10.21504/10962/172191
- Description: Conjugates of nanomaterials and metallophthalocyanines (MPcs) have been prepared and their electrocatalytic activity studied. The prepared nanomaterials are zinc oxide and silver nanoparticles, reduced graphene oxide nanosheets and semiconductor quantum dots. The MPcs used in this work are cobalt (II) (1a), manganese(III) (1b) and iron (II) (1c) 2,9(10),16(17),23(24)- tetrakis 4-((4-ethynylbenzyl) oxy) phthalocyaninato, 2,9(10),16(17),23(24)- tetrakis(5-pentyn-oxy) cobalt (II) phthalocyaninato (2), 9(10),16(17),23(24)- tris-[4-tert-butylphenoxy)-2- (4-ethylbezyl-oxy) cobalt (II) phthalocyaninato (3), 9(10),16(17),23(24)- tris-[4-tertbutylphenoxy)-2-(pent-4yn-yloxy)] cobalt (II) phthalocyaninato (4), cobalt (II) (5a) and manganese (III) (5b) 2,9(10),16(17),23(24)- tetrakis [4-(4-(5-chloro-1H-benzo [d]imidazol-2-yl)phenoxy] phthalocyaninato and 9(10),16(17),23(24)- tris tert butyl phenoxy- 2- [4-(4-(5-chloro-1H-benzo[d]imidazole-2-yl)phenoxy] cobalt (II) phthalocyaninato (6). Some of these MPcs (1a, 3 and 4) were directly clicked on azide grafted electrode, while some (1b, 1c, 2, 5a and 5b) were clicked to azide functionalised nanomaterials and then drop-dried on the electrodes. One phthalocyanine (5b) was drop-dried on the electrode then silver nanoparticles were electrodeposited on it taking advantage of metal-N bond. Scanning electrochemical microscopy, voltammetry, chronoamperometry, electrochemical impedance spectroscopy are among electrochemical methods used to characterise modified electrodes. Transmission electron microscopy, X-ray photoelectron spectroscopy, Xray diffractometry, Raman spectroscopy and infrared spectroscopy were employed to study surface functionalities, morphology and topography of the nanomaterials and complexes. Electrocatalytic activity of the developed materials were studied towards oxidation of 2-mercaptoethanol, hydrazine and hydrogen peroxide while the reduction study was based on oxygen and hydrogen peroxide. In general, the conjugates displayed superior catalytic activity when compared to individual materials. Complex 2 alone and when conjugated to zinc oxide nanoparticles were studied for their nonlinear optical behaviour. And the same materials were explored for their hydrazine detection capability. The aim of this study was to develop sensitive, selective and affordable sensors for selected organic waste pollutants. Conjugates were found to achieve the aim of the study compared to when individual materials were employed.
- Full Text:
- Date Issued: 2021
“Munhu wese ihama yako (everyone is your relative)”: Ubuntu and the social inclusion of students with disabilities at South African universities
- Authors: Chiwandire, Desire
- Date: 2021
- Subjects: College students with disabilities -- Education -- South Africa , Inclusive education -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/170578 , vital:41938 , 10.21504/10962/170578
- Description: Background: During apartheid, South African students with disabilities (SWDs) were educated in special schools and taught an inferior curriculum. Black learners with disabilities were discriminated against on grounds of both race and disability. Following South Africa’s first democratic election in 1994, the African National Congress (ANC) government put in place arrange of new laws to address the educational and other needs of those disadvantaged under apartheid, including persons with disabilities (PWDs). The South African government is a signatory of the 2006 United Nations Convention on the Rights of Persons with Disabilities (UNCRPD) which has resulted in the country assuming obligations to promote inclusive education for ASWDs. However, research (see, for instance, Chiwandire & Vincent 2019; Chiwandire 2019; Mutanga 2019; Majoko & Phasha 2018; Mutanga et al. 2018; Mutanga 2017a; Chiwandire 2017; Israel 2017) has shown that SWDs continue to fare differently in comparison to their non-disabled peers in terms of participation in education with the likelihood of success. Higher education institutions (HEIs) have thus been urged to create conducive environments for the academic inclusion of SWDs with particular attention being paid to lecturers employing inclusive instructional strategies as well as flexible curricula, if they are to ensure the equal opportunity for academic success of SWDs in the regular classroom setting. The focus, to date, on academic inclusion, while important, has meant that issues relating to the social inclusion of SWDs have received minimal attention. Purpose: To date, there is a dearth of South African studies which have investigated the social inclusion needs of SWDs on South African campuses. Although a number of studies have given voice to the perspectives of SWDs and lecturers, with respect to their experiences in relation to matters of academic inclusion in South African higher education (HE), few have focused on Disability Unit Staff Members(DUSMs) who are pivotal to ensuring fair and equitable policies and practices for SWDs in HEIs. Disability Studies (DS) as a field has been criticised for being dominated by voices from the Global North, which fail to consider or effectively theorise Global South disability experiences in a contextually relevant way. The thesis argues that the failure to recognise the value of diversity and to treat SWDs as valued and welcomed participants in South African HEIs partly stems from policy, practice and relationships being informed by the Western individualist paradigm that prizes individual achievement and success rather than cooperation and mutuality. The African philosophy of Ubuntu, which stresses values of communalism, hospitality and respect for human dignity is offered here as an alternative starting point for achieving genuinely inclusive campuses. Methods: In-depth face-to-face qualitative interviews were conducted with 40 participants, most of whom were, at the time of being interviewed, Heads of Disability Units and DUSMs based at 10 different universities in four of South Africa’s nine provinces. Data were coded and analysed using Braun & Clarke’s (2006) method of inductive and deductive thematic analysis. Results: The findings of this study indicate that South African campuses are ableist spaces in which the social needs of SWDs are not prioritised. The thesis argues that in order for campuses to become genuinely inclusive, South African campuses ought to seek to inculcate in their members the values of the African worldview Ubuntu, in contrast to the dominant Western individualist orthodoxy. SWDs are being excluded and denied a sense of belonging and equal participation despite universities giving lip service to embracing such inclusive education-oriented values as co-operative learning. Non-disabled students steeped in Western individualism, which affirms the solitary pursuit of individual success rather than the value of interdependence and diversity, end up marginalising SWDs who are seen as less capable. DUSMs addressing the needs of SWDs through an ableist/Western individualist lens are not challenging unfair practices which are impairing the dignity of SWDs, particularly students with physical disabilities who are being forced to “fit into” oppressive inaccessible built environments on campuses. These DUSMs may unwittingly re-inscribe ableist assumptions that normalise discrimination against SWDs. Conclusions and Recommendations: Ubuntu values offer a starting point for building mutual respect and interdependence between SWDs and their non-disabled peers. The thesis finds however that as was the case in traditional African communities, which embraced the values of Ubuntu, acts of leadership are required if Ubuntu’s values of human dignity, mutual respect and acceptance are to be fostered on campuses. In a range of important ways, the dignity of SWDs is not respected at HEIs in South Africa. This includes, for example, such practical matters as the inaccessibility of toilets to wheelchair users and the lack of appropriate signage for blind students. Disrespectful attitudes and assumptions about SWDs on the part of non-disabled university members also result in SWDs’ human dignity being impaired. Ubuntu’s value of hospitality stresses the importance of promoting relations of group solidarity and interdependence between SWDs and their non-disabled peers. Both academic inclusion-oriented programmes and the promotion of a wide range of social activities, involving both SWDs and non-disabled students, can play an important role in cultivating the formation of long-term fruitful and respectful friendships between SWDs and non-disabled students. An enabling classroom environment alone is not enough to holistically address the social inclusion needs of SWDs. South African HEIs that embrace the Ubuntu values of communalism, human dignity and hospitality will be in a position to respect the needs of SWDs as “whole persons”. Amongst other things, this requires DUSMs to be fully empowered to make important decisions regarding vital matters such as disability inclusion, and it necessitates university management to relinquish their power, so that they may work collaboratively with DUSMs and SWDs, all on equal footing, to ensure that HE funding allocation, policy and planning also prioritises the social needs of SWDs.
- Full Text:
- Date Issued: 2021
- Authors: Chiwandire, Desire
- Date: 2021
- Subjects: College students with disabilities -- Education -- South Africa , Inclusive education -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/170578 , vital:41938 , 10.21504/10962/170578
- Description: Background: During apartheid, South African students with disabilities (SWDs) were educated in special schools and taught an inferior curriculum. Black learners with disabilities were discriminated against on grounds of both race and disability. Following South Africa’s first democratic election in 1994, the African National Congress (ANC) government put in place arrange of new laws to address the educational and other needs of those disadvantaged under apartheid, including persons with disabilities (PWDs). The South African government is a signatory of the 2006 United Nations Convention on the Rights of Persons with Disabilities (UNCRPD) which has resulted in the country assuming obligations to promote inclusive education for ASWDs. However, research (see, for instance, Chiwandire & Vincent 2019; Chiwandire 2019; Mutanga 2019; Majoko & Phasha 2018; Mutanga et al. 2018; Mutanga 2017a; Chiwandire 2017; Israel 2017) has shown that SWDs continue to fare differently in comparison to their non-disabled peers in terms of participation in education with the likelihood of success. Higher education institutions (HEIs) have thus been urged to create conducive environments for the academic inclusion of SWDs with particular attention being paid to lecturers employing inclusive instructional strategies as well as flexible curricula, if they are to ensure the equal opportunity for academic success of SWDs in the regular classroom setting. The focus, to date, on academic inclusion, while important, has meant that issues relating to the social inclusion of SWDs have received minimal attention. Purpose: To date, there is a dearth of South African studies which have investigated the social inclusion needs of SWDs on South African campuses. Although a number of studies have given voice to the perspectives of SWDs and lecturers, with respect to their experiences in relation to matters of academic inclusion in South African higher education (HE), few have focused on Disability Unit Staff Members(DUSMs) who are pivotal to ensuring fair and equitable policies and practices for SWDs in HEIs. Disability Studies (DS) as a field has been criticised for being dominated by voices from the Global North, which fail to consider or effectively theorise Global South disability experiences in a contextually relevant way. The thesis argues that the failure to recognise the value of diversity and to treat SWDs as valued and welcomed participants in South African HEIs partly stems from policy, practice and relationships being informed by the Western individualist paradigm that prizes individual achievement and success rather than cooperation and mutuality. The African philosophy of Ubuntu, which stresses values of communalism, hospitality and respect for human dignity is offered here as an alternative starting point for achieving genuinely inclusive campuses. Methods: In-depth face-to-face qualitative interviews were conducted with 40 participants, most of whom were, at the time of being interviewed, Heads of Disability Units and DUSMs based at 10 different universities in four of South Africa’s nine provinces. Data were coded and analysed using Braun & Clarke’s (2006) method of inductive and deductive thematic analysis. Results: The findings of this study indicate that South African campuses are ableist spaces in which the social needs of SWDs are not prioritised. The thesis argues that in order for campuses to become genuinely inclusive, South African campuses ought to seek to inculcate in their members the values of the African worldview Ubuntu, in contrast to the dominant Western individualist orthodoxy. SWDs are being excluded and denied a sense of belonging and equal participation despite universities giving lip service to embracing such inclusive education-oriented values as co-operative learning. Non-disabled students steeped in Western individualism, which affirms the solitary pursuit of individual success rather than the value of interdependence and diversity, end up marginalising SWDs who are seen as less capable. DUSMs addressing the needs of SWDs through an ableist/Western individualist lens are not challenging unfair practices which are impairing the dignity of SWDs, particularly students with physical disabilities who are being forced to “fit into” oppressive inaccessible built environments on campuses. These DUSMs may unwittingly re-inscribe ableist assumptions that normalise discrimination against SWDs. Conclusions and Recommendations: Ubuntu values offer a starting point for building mutual respect and interdependence between SWDs and their non-disabled peers. The thesis finds however that as was the case in traditional African communities, which embraced the values of Ubuntu, acts of leadership are required if Ubuntu’s values of human dignity, mutual respect and acceptance are to be fostered on campuses. In a range of important ways, the dignity of SWDs is not respected at HEIs in South Africa. This includes, for example, such practical matters as the inaccessibility of toilets to wheelchair users and the lack of appropriate signage for blind students. Disrespectful attitudes and assumptions about SWDs on the part of non-disabled university members also result in SWDs’ human dignity being impaired. Ubuntu’s value of hospitality stresses the importance of promoting relations of group solidarity and interdependence between SWDs and their non-disabled peers. Both academic inclusion-oriented programmes and the promotion of a wide range of social activities, involving both SWDs and non-disabled students, can play an important role in cultivating the formation of long-term fruitful and respectful friendships between SWDs and non-disabled students. An enabling classroom environment alone is not enough to holistically address the social inclusion needs of SWDs. South African HEIs that embrace the Ubuntu values of communalism, human dignity and hospitality will be in a position to respect the needs of SWDs as “whole persons”. Amongst other things, this requires DUSMs to be fully empowered to make important decisions regarding vital matters such as disability inclusion, and it necessitates university management to relinquish their power, so that they may work collaboratively with DUSMs and SWDs, all on equal footing, to ensure that HE funding allocation, policy and planning also prioritises the social needs of SWDs.
- Full Text:
- Date Issued: 2021
A best practice guideline for screening and managing chorioamnionitis
- Authors: Du Plessis, Allison Herlene
- Date: 2020
- Subjects: Bacterial diseases
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/46374 , vital:39575
- Description: Due to the complex nature of chorioamnionitis, women are often misdiagnosed, undiagnosed or only diagnosed after birth when it is too late to prevent maternal and neonatal complications. A lack of a comprehensive best practice guidelinefor screening and managing women withchorioamnionitis resultsin delayed treatment and management that could minimise maternal and neonatal complications. Saving Babiesreported that unexplained intra-uterine deathsremained the main primary (obstetric) cause of death for babies with a weight above 1000g (24.4%of all deaths). Of these unexplained uterine deaths, 33% are of normal birth weight (>2500g), and,therefore,most likely term gestation. Saving Babies further reported that 22.9% of all live births in South Africa was premature and 22.8% of birthswere unexplained intra-uterine deaths. Prematurity is one major complication of chorioamnionitis. When susceptibility for chorioamnionitis is considered during early pregnancy, it is possible to intervene and prevent or even reduce the incidences and complications of chorioamnionitis.A qualitative research study was conducted in three phases. In Phase One(Part One), a theoretically constructed patient scenario of chorioamnionitis was presented to ten midwives,and semi-structured individual interviews were done to elicit information regarding how they screen for and manage chorioamnionitis. In Phase One(Part Two), experienced medical practitioners in the field of obstetrics and gynaecology were individually interviewed, also using semi-structured individual interviewsto gain their views regarding chorioamnionitis as a contributing factor to maternal morbidity and mortality. Qualitative findings in Phase Oneindicated that there is a general lack of knowledge regarding chorioamnionitis among midwives, resulting ininadequate screening, misdiagnosis and mismanagement of the condition. Experienced medical practitioners confirmed that chorioamnionitis is underdiagnosed, misdiagnosed or undiagnosed and underreported,and they hold views that it is difficult to treat and control pregnancy-related infections according to current practice.An integrative literature review was conductedin Phase Twoand literature regarding diagnostic biomarkers, screening options to diagnose chorioamnionitis and management of chorioamnionitis were extracted. After evidence synthesisofPhase Oneand Phase Twodata, a best practice guidelinefor screening and managing viiwomen withchorioamnionitiswas developed usingthe National Institute for Health and Clinical Excellence guideline development approach in Phase Three. The purpose of the best practice guideline for screening and managing women with chorioamnionitis was to provide a guideline onhow to manage women who are at risk and those who present with signs and symptoms of chorioamnionitis at any stage during their pregnancy. Five recommendations were made that involve screening for chorioamnionitisand causative factors, biomarkers to diagnose chorioamnionitis, management of chorioamnionitis that includes pharmacological and non-pharmacological management, and health education to women.Ethics for this research study were guided by the ethical principles and guidelines of the Belmont Report. The trustworthiness of this research study was adopted from Ravitch and Carl,and was based on criticality, reflexivity, collaboration, and rigour. An independent coder and reviewer wereto verify the data that were included in the best practice guideline. Expert reviewersappraised the best practice guidelineusing Appraisal of Guidelines for Research and Evaluation II tools.
- Full Text:
- Date Issued: 2020
- Authors: Du Plessis, Allison Herlene
- Date: 2020
- Subjects: Bacterial diseases
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/46374 , vital:39575
- Description: Due to the complex nature of chorioamnionitis, women are often misdiagnosed, undiagnosed or only diagnosed after birth when it is too late to prevent maternal and neonatal complications. A lack of a comprehensive best practice guidelinefor screening and managing women withchorioamnionitis resultsin delayed treatment and management that could minimise maternal and neonatal complications. Saving Babiesreported that unexplained intra-uterine deathsremained the main primary (obstetric) cause of death for babies with a weight above 1000g (24.4%of all deaths). Of these unexplained uterine deaths, 33% are of normal birth weight (>2500g), and,therefore,most likely term gestation. Saving Babies further reported that 22.9% of all live births in South Africa was premature and 22.8% of birthswere unexplained intra-uterine deaths. Prematurity is one major complication of chorioamnionitis. When susceptibility for chorioamnionitis is considered during early pregnancy, it is possible to intervene and prevent or even reduce the incidences and complications of chorioamnionitis.A qualitative research study was conducted in three phases. In Phase One(Part One), a theoretically constructed patient scenario of chorioamnionitis was presented to ten midwives,and semi-structured individual interviews were done to elicit information regarding how they screen for and manage chorioamnionitis. In Phase One(Part Two), experienced medical practitioners in the field of obstetrics and gynaecology were individually interviewed, also using semi-structured individual interviewsto gain their views regarding chorioamnionitis as a contributing factor to maternal morbidity and mortality. Qualitative findings in Phase Oneindicated that there is a general lack of knowledge regarding chorioamnionitis among midwives, resulting ininadequate screening, misdiagnosis and mismanagement of the condition. Experienced medical practitioners confirmed that chorioamnionitis is underdiagnosed, misdiagnosed or undiagnosed and underreported,and they hold views that it is difficult to treat and control pregnancy-related infections according to current practice.An integrative literature review was conductedin Phase Twoand literature regarding diagnostic biomarkers, screening options to diagnose chorioamnionitis and management of chorioamnionitis were extracted. After evidence synthesisofPhase Oneand Phase Twodata, a best practice guidelinefor screening and managing viiwomen withchorioamnionitiswas developed usingthe National Institute for Health and Clinical Excellence guideline development approach in Phase Three. The purpose of the best practice guideline for screening and managing women with chorioamnionitis was to provide a guideline onhow to manage women who are at risk and those who present with signs and symptoms of chorioamnionitis at any stage during their pregnancy. Five recommendations were made that involve screening for chorioamnionitisand causative factors, biomarkers to diagnose chorioamnionitis, management of chorioamnionitis that includes pharmacological and non-pharmacological management, and health education to women.Ethics for this research study were guided by the ethical principles and guidelines of the Belmont Report. The trustworthiness of this research study was adopted from Ravitch and Carl,and was based on criticality, reflexivity, collaboration, and rigour. An independent coder and reviewer wereto verify the data that were included in the best practice guideline. Expert reviewersappraised the best practice guidelineusing Appraisal of Guidelines for Research and Evaluation II tools.
- Full Text:
- Date Issued: 2020
A classification of large wetlands in Africa’s elevated drylands based on their formation, structure, and hydrological functioning using Earth Observation (EO) data and Geographic Information System (GIS)
- Authors: Lidzhegu, Zwidofhelangani
- Date: 2020
- Subjects: Wetlands -- Africa -- Classification , Wetlands -- Africa -- Research , Wetlands -- Africa -- Monitoring , Topographical surveying -- Africa , Hydrological surveys == Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142668 , vital:38100
- Description: Due to wetland inaccessibility and limited wetland geomorphological studies, there is limited information on the geomorphological origin and hydrological functioning of different types of wetlands in Africa’s elevated drylands. As a result, there is limited information for the development of a comprehensive wetland classification system that classifies wetlands based on long-term geomorphic processes that determine their formation and shape, their structure and hydrological functioning. Therefore, the current study was designed to classify large wetlands in Africa’s elevated drylands based on processes that determine their formation, and shape their structure and hydrological functioning using remote sensing and Geographic Information System (GIS) techniques. Although wetlands perform a number of hydrological functions including groundwater recharge and water purification, the current study focuses mainly on their flood attenuation function. Detailed analysis of topographic information was undertaken using Shuttle Radar Topographic Mission (SRTM) elevations measured at the scale of 30 m x 30 m. LandsatLook and Google Earth images, tectonic as well as geological data were used as supplementary data for developing an understanding of the origin, structure and hydrological characteristics of wetlands. The Principal Component Analysis (PCA) of wetland environmental variables was used to identify and explain wetland heterogeneity. The results of the study showed that fluvial processes, tectonic history and the evolution of Africa’s landscape played a fundamental role in the formation and evolution of wetlands. This study demonstrates a wide range of processes that contribute to wetland formation, structure and functioning. At one extreme it is clear that tectonic processes may be primarily responsible for the creation of basins that host wetlands. At another extreme, wetlands may be structured primarily by fluvial processes. At a third extreme are wetlands that superficially appear to be structured by fluvial processes, but which have their structures modified by gradual rising of the base level at their distal ends, either through marginal uplift adjacent to rift valleys, or through aggradation of a floodplain that blocks a tributary valley. Overall, the classification of wetlands considered in this study can be summarised into four distinct groupings, with two of these divided further into two groupings each: (1) Tectonic basins with little or no indication of fluvial development (Bahi and Wembere wetlands), (2) Tectonic basins evolving towards a wetland with a structure increasingly shaped by fluvial characteristics (Usangu wetland), (3) Fluvially modified valleys with a local base level at the toe of the wetland such as a resistant lithology or a tectonic control that limits the rate of incision of easily weathered and eroded lithologies, leading to valley widening and longitudinal slope reduction, which are of two distinct types: (a) With a catchment on Kalahari Group sediment that is transported fluvially as bedload, and therefore with no prominent alluvial ridge or backwater depressions (Upper Zambezi and Barotse wetlands), (b) With a catchment that produces abundant fine sediment that is deposited as overbank sediments, leading to channel migration via meandering and to the construction of an elevated alluvial ridge (Lufira wetland), (4) Fluvially modified basins with evidence of gradual elevation of the base level at the toe of the wetland, which are of two types: (a) Tectonic marginal rift valley uplift such that they behave more as depression wetlands rather than as wetlands shaped by fluvial processes (Kafue and Luapula wetlands), (b) Tributary valley wetlands blocked by aggradation of the trunk valley (Lukanga wetland). In conclusion, although few geomorphological studies have been conducted on southern African wetlands because of their inaccessibility, Africa’s surface topography and its historical evolution, as well as aridity, provide an opportunity for illustrating the important role that the long-term tectonic, geological and geomorphological processes play in determining wetland origin, structure and dynamics. GIS methodology and Earth Observation (EO) data on the other hand, provide a practical means for acquiring information on inaccessible and hard to traverse wetland systems. A novel cut-and-fill approach for delineating wetlands from a Digital Elevation Model (DEM) was presented as another way in which GIS methodology and Earth Observation (EO) data can provide practical means for assessing inaccessible and hard to traverse wetland systems.
- Full Text:
- Date Issued: 2020
- Authors: Lidzhegu, Zwidofhelangani
- Date: 2020
- Subjects: Wetlands -- Africa -- Classification , Wetlands -- Africa -- Research , Wetlands -- Africa -- Monitoring , Topographical surveying -- Africa , Hydrological surveys == Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142668 , vital:38100
- Description: Due to wetland inaccessibility and limited wetland geomorphological studies, there is limited information on the geomorphological origin and hydrological functioning of different types of wetlands in Africa’s elevated drylands. As a result, there is limited information for the development of a comprehensive wetland classification system that classifies wetlands based on long-term geomorphic processes that determine their formation and shape, their structure and hydrological functioning. Therefore, the current study was designed to classify large wetlands in Africa’s elevated drylands based on processes that determine their formation, and shape their structure and hydrological functioning using remote sensing and Geographic Information System (GIS) techniques. Although wetlands perform a number of hydrological functions including groundwater recharge and water purification, the current study focuses mainly on their flood attenuation function. Detailed analysis of topographic information was undertaken using Shuttle Radar Topographic Mission (SRTM) elevations measured at the scale of 30 m x 30 m. LandsatLook and Google Earth images, tectonic as well as geological data were used as supplementary data for developing an understanding of the origin, structure and hydrological characteristics of wetlands. The Principal Component Analysis (PCA) of wetland environmental variables was used to identify and explain wetland heterogeneity. The results of the study showed that fluvial processes, tectonic history and the evolution of Africa’s landscape played a fundamental role in the formation and evolution of wetlands. This study demonstrates a wide range of processes that contribute to wetland formation, structure and functioning. At one extreme it is clear that tectonic processes may be primarily responsible for the creation of basins that host wetlands. At another extreme, wetlands may be structured primarily by fluvial processes. At a third extreme are wetlands that superficially appear to be structured by fluvial processes, but which have their structures modified by gradual rising of the base level at their distal ends, either through marginal uplift adjacent to rift valleys, or through aggradation of a floodplain that blocks a tributary valley. Overall, the classification of wetlands considered in this study can be summarised into four distinct groupings, with two of these divided further into two groupings each: (1) Tectonic basins with little or no indication of fluvial development (Bahi and Wembere wetlands), (2) Tectonic basins evolving towards a wetland with a structure increasingly shaped by fluvial characteristics (Usangu wetland), (3) Fluvially modified valleys with a local base level at the toe of the wetland such as a resistant lithology or a tectonic control that limits the rate of incision of easily weathered and eroded lithologies, leading to valley widening and longitudinal slope reduction, which are of two distinct types: (a) With a catchment on Kalahari Group sediment that is transported fluvially as bedload, and therefore with no prominent alluvial ridge or backwater depressions (Upper Zambezi and Barotse wetlands), (b) With a catchment that produces abundant fine sediment that is deposited as overbank sediments, leading to channel migration via meandering and to the construction of an elevated alluvial ridge (Lufira wetland), (4) Fluvially modified basins with evidence of gradual elevation of the base level at the toe of the wetland, which are of two types: (a) Tectonic marginal rift valley uplift such that they behave more as depression wetlands rather than as wetlands shaped by fluvial processes (Kafue and Luapula wetlands), (b) Tributary valley wetlands blocked by aggradation of the trunk valley (Lukanga wetland). In conclusion, although few geomorphological studies have been conducted on southern African wetlands because of their inaccessibility, Africa’s surface topography and its historical evolution, as well as aridity, provide an opportunity for illustrating the important role that the long-term tectonic, geological and geomorphological processes play in determining wetland origin, structure and dynamics. GIS methodology and Earth Observation (EO) data on the other hand, provide a practical means for acquiring information on inaccessible and hard to traverse wetland systems. A novel cut-and-fill approach for delineating wetlands from a Digital Elevation Model (DEM) was presented as another way in which GIS methodology and Earth Observation (EO) data can provide practical means for assessing inaccessible and hard to traverse wetland systems.
- Full Text:
- Date Issued: 2020
A combined modelling approach for simulating channel–wetland exchanges in large African river basins
- Authors: Makungu, Eunice J
- Date: 2020
- Subjects: Watersheds -- Africa , Watershed management -- Africa , Water resources development -- Africa -- International cooperation , Floodplain management -- Africa , Wetland ecology -- Simulation methods -- Africa , Wetland management -- Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/123288 , vital:35424
- Description: In Africa, many large and extensive wetlands are hydrologically connected to rivers, and their environmental integrity, as well as their influence on downstream flow regimes, depends on the prevailing channel–wetland exchange processes. These processes are inherently complex and vary spatially and temporally. Understanding channel–wetland exchanges is therefore, indispensable for the effective management of wetlands and the associated river basins. However, this information is limited in most of the river basins containing large wetlands in Africa. Furthermore, it is important to understand the links between upstream and downstream flow regimes and the wetland dynamics themselves, specifically where there are water resource developments that may affect these links (upstream developments), or be affected by them (downstream developments). Hydrological modelling of the entire basin using basin-scale models that include wetland components in their structures can be used to provide the information required to manage water resources in such basins. However, the level of detail of wetland processes included in many basin-scale models is typically very low and the lack of understanding of the wetland dynamics makes it difficult to quantify the relevant parameters. Detailed hydraulic models represent the channel-wetland exchanges in a much more explicit manner, but require relatively more data and time resources to establish than coarser scale hydrological models. The main objective of this study was, therefore, to investigate the use of a detailed hydraulic wetland model to provide a better understanding of channel–wetland exchanges and wetland dynamics, and to use the results to improve the parameterisation of a basin-scale model. The study focused on improving the water resource assessments modelling of three data-scarce African river basins that contain large wetlands: the floodplains of the Luangwa and Upper Zambezi River basins and the Usangu wetland in the Upper Great Ruaha River basin. The overall objective was achieved through a combined modelling approach that uses a detailed high-resolution LISFLOOD-FP hydraulic model to inform the structure and parameters of the GW Pitman monthly hydrological model. The results from the LISFLOOD-FP were used to improve the understanding of the channel–wetland exchange dynamics and to establish the wetland parameters required in the GW Pitman model. While some wetland parameters were directly quantified from the LISFLOOD-FP model results, others, which are highly empirical, were estimated by manually calibrating the GW Pitman wetland sub-model implemented in excel spreadsheets containing the LISFLOOD-FP model results. Finally, the GW Pitman model with the inclusion of the estimated wetland parameters was applied for each basin and the results compared to the available downstream observed flow data. The two models have been successfully applied in southern Africa, with the GW Pitman model being one of the most widely applied hydrological models in this region. To address the issue of data scarcity, during setup of these models, the study mainly relied on the global datasets which clearly adds to the overall uncertainty of the modelling approach. However, this is a typical situation for most of the data scarce regions of the continent. A number of challenges were, however, faced during the setup of the LISFLOOD-FP, mainly due to the limitations of the data inputs. Some of the LISFLOOD-FP data inputs include boundary conditions (upstream and downstream), channel cross-sections and wetland topography. In the absence of observed daily flows to quantify the wetland upstream boundary conditions, monthly flow volumes simulated using the GW Pitman monthly model (without including the wetland sub-model) were disaggregated into daily flows using a disaggregation sub-model. The simulated wetland inflows were evaluated using the observed flow data for downstream gauging stations that include the wetland effects. The results highlighted that it is important to understand the possible impacts of each wetland on the downstream flow regime during the evaluations of the model simulation results. Although the disaggregation approach cannot be validated due to a lack of observed data, it at least enables the simulated monthly flows to be used in the daily time step hydraulic model. One of the recommendations is that improvements are required in gauging station networks to provide more observed information for the main river and the larger tributary inflows into these large and important wetland systems. Even a limited amount of newly observed data would be helpful to reduce some of the uncertainties in the combined modelling approach. The SRTM 90 m DEM (used to represent wetland topography) was filtered to reduce local variations and noise effects (mainly vegetation bias), but there were some pixels that falsely affect the inundation results, and the recently released vegetation-corrected DEMs are suggested to improve the simulation results. Channel cross-section values derived from global datasets should be examined because some widths estimated from the Andreadis et al. (2013) dataset were found to be over-generalised and did not reflect widths measured using high-resolution Google Earth in many places. There is an indication that channel cross-sections digitised from Google Earth images can be successfully used in the model setup except in densely vegetated swamps where the values are difficult to estimate, and in such situations, field measured cross-section data are required. Small channels such as those found in the Usangu wetland could play major role in the exchange dynamics, but digitising them all was not straightforward and only key ones were included in the model setup. Clearly, this inevitably introduced uncertainties in the simulated results, and future studies should consider applying methods that simplify extractions of most of these channels from high-resolution images to improve the simulated results. The study demonstrated that the wetland and channel physical characteristics, as well as the seasonal flow magnitude, largely influence the channel–wetland exchanges and wetland dynamics. The inundation results indicated that the area–storage and storage–inflow relationships form hysteretic curves, but the shape of these curves vary with flood magnitude and wetland type. Anticlockwise hysteresis curves were observed in both relationships for the floodplains (Luangwa and Barotse), whereas there appears to be no dominant curve type for the Usangu wetlands. The lack of well-defined hysteretic relationships in the Usangu could be related to some of the difficulties (and resulting uncertainties) that were experienced in setting up the model for this wetland. The storage–inflow relationships in all wetlands have quite complex rising limbs due to multiple flow peaks during the main wet season. The largest inundation area and storage volume for the Barotse and Usangu wetlands occurred after the peak discharge of the wet season, a result that is clearly related to the degree of connectivity between the main channel and those areas of the wetlands that are furthest away from the channel. Hysteresis effects were found to increase with an increase in flood magnitudes and temporal variations in the wetland inflows. Overall, hysteresis behaviour is common in large wetlands and it is recommended that hysteresis curves should be reflected in basin-scale modelling of large river basins with substantial wetland areas. At a daily time scale, inflow–outflow relationships showed a significant peak reduction and a delayed time to peak of several weeks in the Barotse and Usangu wetlands, whereas the attenuation effects of the Luangwa floodplain are minimal. To a large extent, the LISFLOOD-FP results provided useful information to establish wetland parameters and assess the structure of Pitman wetland sub-model. The simple spreadsheet used to estimate wetland parameters did not account for the wetland water transfers from the upstream to the next section downstream (the condition that is included in the LISFLOOD-FP model) for the case when the wetlands were distributed across more than one sub-basin. It is recommended that a method that allows for the upstream wetland inflows and the channel inflows should be included in the spreadsheet. The same is true to the Pitman model structure, and a downstream transfer of water can be modelled through return flows to the channel. The structure of the wetland sub-model was modified to allow an option for the return flows to occur at any time during the simulation period to provide for types of wetlands (e.g. the Luangwa) where spills from the channel and drainage back to the channel occur simultaneously. The setup of the GW Pitman model with the inclusion of wetland parameters improved the simulation results. However, the results for the Usangu wetlands were not very satisfactory and the collection of additional field data related to exchange dynamics is recommended to achieve improvements. The impacts of the Luangwa floodplain on the flow regime of the Luangwa River are very small at the monthly time scale, whereas the Barotse floodplain system and the Usangu wetlands extensively regulate flows of the Zambezi River and the Great Ruaha River, respectively. The results highlighted the possibilities of regionalising some wetland parameters using an understanding of wetland physical characteristics and their water exchange dynamics. However, some parameters remain difficult to quantify in the absence of site-specific information about the water exchange dynamics. The overall conclusion is that the approach implemented in this study presents an important step towards the improvements of water resource assessments modelling for research and practical purposes in data-scarce river basins. This approach is not restricted to the two used models, as it can be applied using different model combinations to achieve similar study purpose.
- Full Text:
- Date Issued: 2020
A combined modelling approach for simulating channel–wetland exchanges in large African river basins
- Authors: Makungu, Eunice J
- Date: 2020
- Subjects: Watersheds -- Africa , Watershed management -- Africa , Water resources development -- Africa -- International cooperation , Floodplain management -- Africa , Wetland ecology -- Simulation methods -- Africa , Wetland management -- Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/123288 , vital:35424
- Description: In Africa, many large and extensive wetlands are hydrologically connected to rivers, and their environmental integrity, as well as their influence on downstream flow regimes, depends on the prevailing channel–wetland exchange processes. These processes are inherently complex and vary spatially and temporally. Understanding channel–wetland exchanges is therefore, indispensable for the effective management of wetlands and the associated river basins. However, this information is limited in most of the river basins containing large wetlands in Africa. Furthermore, it is important to understand the links between upstream and downstream flow regimes and the wetland dynamics themselves, specifically where there are water resource developments that may affect these links (upstream developments), or be affected by them (downstream developments). Hydrological modelling of the entire basin using basin-scale models that include wetland components in their structures can be used to provide the information required to manage water resources in such basins. However, the level of detail of wetland processes included in many basin-scale models is typically very low and the lack of understanding of the wetland dynamics makes it difficult to quantify the relevant parameters. Detailed hydraulic models represent the channel-wetland exchanges in a much more explicit manner, but require relatively more data and time resources to establish than coarser scale hydrological models. The main objective of this study was, therefore, to investigate the use of a detailed hydraulic wetland model to provide a better understanding of channel–wetland exchanges and wetland dynamics, and to use the results to improve the parameterisation of a basin-scale model. The study focused on improving the water resource assessments modelling of three data-scarce African river basins that contain large wetlands: the floodplains of the Luangwa and Upper Zambezi River basins and the Usangu wetland in the Upper Great Ruaha River basin. The overall objective was achieved through a combined modelling approach that uses a detailed high-resolution LISFLOOD-FP hydraulic model to inform the structure and parameters of the GW Pitman monthly hydrological model. The results from the LISFLOOD-FP were used to improve the understanding of the channel–wetland exchange dynamics and to establish the wetland parameters required in the GW Pitman model. While some wetland parameters were directly quantified from the LISFLOOD-FP model results, others, which are highly empirical, were estimated by manually calibrating the GW Pitman wetland sub-model implemented in excel spreadsheets containing the LISFLOOD-FP model results. Finally, the GW Pitman model with the inclusion of the estimated wetland parameters was applied for each basin and the results compared to the available downstream observed flow data. The two models have been successfully applied in southern Africa, with the GW Pitman model being one of the most widely applied hydrological models in this region. To address the issue of data scarcity, during setup of these models, the study mainly relied on the global datasets which clearly adds to the overall uncertainty of the modelling approach. However, this is a typical situation for most of the data scarce regions of the continent. A number of challenges were, however, faced during the setup of the LISFLOOD-FP, mainly due to the limitations of the data inputs. Some of the LISFLOOD-FP data inputs include boundary conditions (upstream and downstream), channel cross-sections and wetland topography. In the absence of observed daily flows to quantify the wetland upstream boundary conditions, monthly flow volumes simulated using the GW Pitman monthly model (without including the wetland sub-model) were disaggregated into daily flows using a disaggregation sub-model. The simulated wetland inflows were evaluated using the observed flow data for downstream gauging stations that include the wetland effects. The results highlighted that it is important to understand the possible impacts of each wetland on the downstream flow regime during the evaluations of the model simulation results. Although the disaggregation approach cannot be validated due to a lack of observed data, it at least enables the simulated monthly flows to be used in the daily time step hydraulic model. One of the recommendations is that improvements are required in gauging station networks to provide more observed information for the main river and the larger tributary inflows into these large and important wetland systems. Even a limited amount of newly observed data would be helpful to reduce some of the uncertainties in the combined modelling approach. The SRTM 90 m DEM (used to represent wetland topography) was filtered to reduce local variations and noise effects (mainly vegetation bias), but there were some pixels that falsely affect the inundation results, and the recently released vegetation-corrected DEMs are suggested to improve the simulation results. Channel cross-section values derived from global datasets should be examined because some widths estimated from the Andreadis et al. (2013) dataset were found to be over-generalised and did not reflect widths measured using high-resolution Google Earth in many places. There is an indication that channel cross-sections digitised from Google Earth images can be successfully used in the model setup except in densely vegetated swamps where the values are difficult to estimate, and in such situations, field measured cross-section data are required. Small channels such as those found in the Usangu wetland could play major role in the exchange dynamics, but digitising them all was not straightforward and only key ones were included in the model setup. Clearly, this inevitably introduced uncertainties in the simulated results, and future studies should consider applying methods that simplify extractions of most of these channels from high-resolution images to improve the simulated results. The study demonstrated that the wetland and channel physical characteristics, as well as the seasonal flow magnitude, largely influence the channel–wetland exchanges and wetland dynamics. The inundation results indicated that the area–storage and storage–inflow relationships form hysteretic curves, but the shape of these curves vary with flood magnitude and wetland type. Anticlockwise hysteresis curves were observed in both relationships for the floodplains (Luangwa and Barotse), whereas there appears to be no dominant curve type for the Usangu wetlands. The lack of well-defined hysteretic relationships in the Usangu could be related to some of the difficulties (and resulting uncertainties) that were experienced in setting up the model for this wetland. The storage–inflow relationships in all wetlands have quite complex rising limbs due to multiple flow peaks during the main wet season. The largest inundation area and storage volume for the Barotse and Usangu wetlands occurred after the peak discharge of the wet season, a result that is clearly related to the degree of connectivity between the main channel and those areas of the wetlands that are furthest away from the channel. Hysteresis effects were found to increase with an increase in flood magnitudes and temporal variations in the wetland inflows. Overall, hysteresis behaviour is common in large wetlands and it is recommended that hysteresis curves should be reflected in basin-scale modelling of large river basins with substantial wetland areas. At a daily time scale, inflow–outflow relationships showed a significant peak reduction and a delayed time to peak of several weeks in the Barotse and Usangu wetlands, whereas the attenuation effects of the Luangwa floodplain are minimal. To a large extent, the LISFLOOD-FP results provided useful information to establish wetland parameters and assess the structure of Pitman wetland sub-model. The simple spreadsheet used to estimate wetland parameters did not account for the wetland water transfers from the upstream to the next section downstream (the condition that is included in the LISFLOOD-FP model) for the case when the wetlands were distributed across more than one sub-basin. It is recommended that a method that allows for the upstream wetland inflows and the channel inflows should be included in the spreadsheet. The same is true to the Pitman model structure, and a downstream transfer of water can be modelled through return flows to the channel. The structure of the wetland sub-model was modified to allow an option for the return flows to occur at any time during the simulation period to provide for types of wetlands (e.g. the Luangwa) where spills from the channel and drainage back to the channel occur simultaneously. The setup of the GW Pitman model with the inclusion of wetland parameters improved the simulation results. However, the results for the Usangu wetlands were not very satisfactory and the collection of additional field data related to exchange dynamics is recommended to achieve improvements. The impacts of the Luangwa floodplain on the flow regime of the Luangwa River are very small at the monthly time scale, whereas the Barotse floodplain system and the Usangu wetlands extensively regulate flows of the Zambezi River and the Great Ruaha River, respectively. The results highlighted the possibilities of regionalising some wetland parameters using an understanding of wetland physical characteristics and their water exchange dynamics. However, some parameters remain difficult to quantify in the absence of site-specific information about the water exchange dynamics. The overall conclusion is that the approach implemented in this study presents an important step towards the improvements of water resource assessments modelling for research and practical purposes in data-scarce river basins. This approach is not restricted to the two used models, as it can be applied using different model combinations to achieve similar study purpose.
- Full Text:
- Date Issued: 2020
A comparative analysis of the use of participatory practices by indigenous trusts and mainstream development NGOs in Zvimba Communal Area Zimbabwe
- Authors: Mbanje, Bowden Bolt
- Date: 2020
- Subjects: Caritas Zimbabwe , Zvimba Community Share Ownership Trust (ZvCSOT) , Non-governmental organizations -- Zimbabwe -- Zvimba District , Community development -- Zimbabwe -- Zvimba District , Rural development -- Zimbabwe -- Zvimba District , Zvimba Communal Land (Zimbabwe)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167099 , vital:41437
- Description: This thesis compares the extent to which participatory practices have been used by Caritas Zimbabwe, a mainstream NGO, and the Zvimba Community Share Ownership Trust (ZvCSOT), an indigenous Trust, in Zvimba District, Zimbabwe. Participatory development initiatives are common practice in NGO and government development work in Zimbabwe. The thesis begins with a discussion of two aspects of participatory development (PD). Firstly, PD is discussed in relation to decentralization processes where central government transfers administrative and financial authority to sub-national government units in order to enhance the participation of rural communities in development interventions. Secondly, PD is discussed in relation to the increased role of NGOs in development work. During the 1980s and 1990s, shifts in development thinking resulted in NGOs being perceived as important actors who could attend to the development gaps left by an economically incapacitated state. Both NGOs and sub-national government units were seen to be closer to rural communities and so were thought to be in a better position to enhance the participation of these communities in meaningful development projects. An analysis of the practices of the NGO and CSOT under consideration in this study shows that while there has been much rhetorical commitment to participation, community participation in the development interventions of the NGO and the CSOT is inadequate. In introducing and implementing development interventions, there has been a tendency by both the NGO and CSOT to give priority to organizational preferences over local needs. While recognizing the participatory efforts made by mainstream development NGOs (Caritas in particular) and indigenous Trusts (Zvimba Community Share Ownership Trust in particular) in Zimbabwe, this thesis also considers the impact of other factors on participatory development initiatives. A major observation from the study is that in as much as we expect genuine participatory approaches which include grassroots communities’ inputs from the project’s conceptualization all the way to its evaluation, the challenge is that the elites at the higher level (central government and donor offices) have their own development preferences and interests while the elites at the lower levels (local government and NGO offices) also have their own priorities and needs. Consequently, local communities tend to be confined to implementing development projects foisted on them by elites at the higher level as well as those at the lower level. Worse still, the study shows that elites at the lowest level (community) sometimes hijack or take advantage of the imposed projects. Participation has been stalled by elites at various levels of the participatory development ladder. Thus, unless power imbalances are seriously addressed at all levels, participatory development will remain elusive.
- Full Text:
- Date Issued: 2020
- Authors: Mbanje, Bowden Bolt
- Date: 2020
- Subjects: Caritas Zimbabwe , Zvimba Community Share Ownership Trust (ZvCSOT) , Non-governmental organizations -- Zimbabwe -- Zvimba District , Community development -- Zimbabwe -- Zvimba District , Rural development -- Zimbabwe -- Zvimba District , Zvimba Communal Land (Zimbabwe)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167099 , vital:41437
- Description: This thesis compares the extent to which participatory practices have been used by Caritas Zimbabwe, a mainstream NGO, and the Zvimba Community Share Ownership Trust (ZvCSOT), an indigenous Trust, in Zvimba District, Zimbabwe. Participatory development initiatives are common practice in NGO and government development work in Zimbabwe. The thesis begins with a discussion of two aspects of participatory development (PD). Firstly, PD is discussed in relation to decentralization processes where central government transfers administrative and financial authority to sub-national government units in order to enhance the participation of rural communities in development interventions. Secondly, PD is discussed in relation to the increased role of NGOs in development work. During the 1980s and 1990s, shifts in development thinking resulted in NGOs being perceived as important actors who could attend to the development gaps left by an economically incapacitated state. Both NGOs and sub-national government units were seen to be closer to rural communities and so were thought to be in a better position to enhance the participation of these communities in meaningful development projects. An analysis of the practices of the NGO and CSOT under consideration in this study shows that while there has been much rhetorical commitment to participation, community participation in the development interventions of the NGO and the CSOT is inadequate. In introducing and implementing development interventions, there has been a tendency by both the NGO and CSOT to give priority to organizational preferences over local needs. While recognizing the participatory efforts made by mainstream development NGOs (Caritas in particular) and indigenous Trusts (Zvimba Community Share Ownership Trust in particular) in Zimbabwe, this thesis also considers the impact of other factors on participatory development initiatives. A major observation from the study is that in as much as we expect genuine participatory approaches which include grassroots communities’ inputs from the project’s conceptualization all the way to its evaluation, the challenge is that the elites at the higher level (central government and donor offices) have their own development preferences and interests while the elites at the lower levels (local government and NGO offices) also have their own priorities and needs. Consequently, local communities tend to be confined to implementing development projects foisted on them by elites at the higher level as well as those at the lower level. Worse still, the study shows that elites at the lowest level (community) sometimes hijack or take advantage of the imposed projects. Participation has been stalled by elites at various levels of the participatory development ladder. Thus, unless power imbalances are seriously addressed at all levels, participatory development will remain elusive.
- Full Text:
- Date Issued: 2020
A comparative study of conceptualisations and practices of inclusion as an aspect of social justice in three teacher education institutions in Canada, South Africa and Zimbabwe
- Authors: Musara, Ellison
- Date: 2020
- Subjects: Social justice and education , Teachers -- Training of -- Canada , Teachers -- Training of -- South Africa , Teachers -- Training of -- Zimbabwe , Educational sociology -- Canada , Educational sociology -- South Africa , Educational sociology -- Zimbabwe , Educational equalization , Inclusive education , Education -- Moral and ethical aspects , Critical realism
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/144138 , vital:38314
- Description: This study sought to examine understandings and practices of inclusion as social justice in teacher education programmes in three countries: Canada, South Africa and Zimbabwe. While inclusive education has become an issue of increasing importance globally, contemporary research shows that not much attention has been given to the preparation of teachers as a key element in developing inclusive education systems. Recognising that pre-service teacher education is vital to the success and continued development of inclusive educational practice, the purpose of this qualitative study was to better understand the ways in which inclusion is understood and practiced in the field of teacher education. Using Roy Bhaskar’s (1978) critical realism as a metatheory and drawing on Fraser’s substantive theory of social justice (2008, 2009) and Tronto’s ethic of care (1993, 2013), this study explored the extent to which teacher education faculty and teacher candidates understood and practiced inclusion as an aspect of social justice. The data used in this study was generated through individual and focus group interviews and document analysis in three higher education institutions, one in each of the three countries. In Canada, four teacher educators took part in the interviews while five teacher candidates participated in the focus group. Similarly, in South Africa, three teacher educators and eight teacher candidates participated, and in Zimbabwe, four teacher educators and eight teacher candidates took part in the study respectively. Findings from the study revealed that inclusion still means different things to different people, reflecting contrasting theoretical and ideological orientations from which inclusion is considered, while still remaining a major educational policy concern in all three countries. In the Canadian and South African institutions, inclusion is viewed more in terms of systemic educational change in pursuit of equity, social justice and equal educational opportunities for all learners. In the Zimbabwean institution, the primary focus of inclusion remains creating conditions that make it possible for students with disabilities to overcome barriers to learning and participation by providing specialist educational measures and interventions intended to respond to specific forms of impairment. As a comparative study, it is hoped that this study will contribute to the knowledge of variations and patterns in the ways in which inclusive education is shaped by societal forces such as political, economic and cultural conditions.
- Full Text:
- Date Issued: 2020
- Authors: Musara, Ellison
- Date: 2020
- Subjects: Social justice and education , Teachers -- Training of -- Canada , Teachers -- Training of -- South Africa , Teachers -- Training of -- Zimbabwe , Educational sociology -- Canada , Educational sociology -- South Africa , Educational sociology -- Zimbabwe , Educational equalization , Inclusive education , Education -- Moral and ethical aspects , Critical realism
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/144138 , vital:38314
- Description: This study sought to examine understandings and practices of inclusion as social justice in teacher education programmes in three countries: Canada, South Africa and Zimbabwe. While inclusive education has become an issue of increasing importance globally, contemporary research shows that not much attention has been given to the preparation of teachers as a key element in developing inclusive education systems. Recognising that pre-service teacher education is vital to the success and continued development of inclusive educational practice, the purpose of this qualitative study was to better understand the ways in which inclusion is understood and practiced in the field of teacher education. Using Roy Bhaskar’s (1978) critical realism as a metatheory and drawing on Fraser’s substantive theory of social justice (2008, 2009) and Tronto’s ethic of care (1993, 2013), this study explored the extent to which teacher education faculty and teacher candidates understood and practiced inclusion as an aspect of social justice. The data used in this study was generated through individual and focus group interviews and document analysis in three higher education institutions, one in each of the three countries. In Canada, four teacher educators took part in the interviews while five teacher candidates participated in the focus group. Similarly, in South Africa, three teacher educators and eight teacher candidates participated, and in Zimbabwe, four teacher educators and eight teacher candidates took part in the study respectively. Findings from the study revealed that inclusion still means different things to different people, reflecting contrasting theoretical and ideological orientations from which inclusion is considered, while still remaining a major educational policy concern in all three countries. In the Canadian and South African institutions, inclusion is viewed more in terms of systemic educational change in pursuit of equity, social justice and equal educational opportunities for all learners. In the Zimbabwean institution, the primary focus of inclusion remains creating conditions that make it possible for students with disabilities to overcome barriers to learning and participation by providing specialist educational measures and interventions intended to respond to specific forms of impairment. As a comparative study, it is hoped that this study will contribute to the knowledge of variations and patterns in the ways in which inclusive education is shaped by societal forces such as political, economic and cultural conditions.
- Full Text:
- Date Issued: 2020
A critical analysis of the de-peasantisation process in Nepal with specific reference to the role of state land policies since the 1950s
- Authors: Basnet, Jagat
- Date: 2020
- Subjects: Land tenure -- Nepal , Land reform -- Law and legislation -- Nepal , Nepal -- Politics and government , Peasants -- Nepal -- Economic conditions , Panchayat -- Nepal
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/138716 , vital:37667
- Description: The principal objective of this thesis is to offer a critical analysis of the process of de-peasantisation in Nepal since 1950, with a particular focus on the capitalist neo-liberal restructuring of the economy beginning in the early 1990s. The analysis begins by tracing the legacy of feudal land practices and landholdings from the pre-1950 Rana and Shah dynasties. It was under these feudal dynasties that economic and political institutions of extraction first emerged, leading to a landlord-peasant agrarian economy in which peasants (often as tenants/sharecroppers and smallholders) were subordinate to the power nexus between feudal landlords and the ruling dynasties. After 1950, a window of democratic opening was soon interrupted by the formation of the party-less Panchayat system, which lasted from 1960 to 1990. In 1964, a major land reform measure was enacted under the Lands Act, with the goal of enhancing the security and livelihood of the peasantry. However, this process was met with significant resistance by feudal landlords, and actually led to deepening insecurity and the loss of land by peasants, with farmers belonging to lower castes and indigenous groups experiencing this with a greater degree of intensity. The overall result of this period was the beginnings of what is referred to in this study as de-peasantisation. This line of analysis shows that the institutions of extraction remained firmly in place even after the reforms of this period. Finally, the neo-liberal period, which was marked by land titling, the marketisation of land, and the commercialisation of agriculture, represents the late entry of capitalism into Nepal. This period saw the deepening and widening of the process of de-peasantisation, including further loss of peasants’ access to land and a general turn to wage-labour. In this regard, despite propagating the slogan ‘land to the tillers’, the major political parties in Nepal (including the Maoist party) have failed to defend the interests of the peasantry. Some progressive civil society groups have recently sought to do better, but there is also evidence of peasant organisations themselves seeking to resist and oppose the de-peasantisation effects of neo-liberal restructuring. This thesis thus considers the form and extent of de-peasantisation in Nepal, and some responses to it, over an extended period. A broad Marxist-based political economy perspective has been adopted in pursuing the principal thesis objective, but one which argues that there is a symbiotic relationship between economic and political power, such that the latter is not reducible to the former. The thesis draws upon original fieldwork in twenty districts of Nepal, including through the use of a survey, interviews, observations, case studies, and focus group discussions, thus combining both quantitative and qualitative research methods. Based on this fieldwork, it becomes clear that (i) there are major social, economic, and political forces behind the processes of de-peasantisation in the studied districts (and in Nepal more broadly), and that (ii) the Nepali peasantry is becoming increasingly landless, or land-short, and subject to processes of proletarianisation.
- Full Text:
- Date Issued: 2020
- Authors: Basnet, Jagat
- Date: 2020
- Subjects: Land tenure -- Nepal , Land reform -- Law and legislation -- Nepal , Nepal -- Politics and government , Peasants -- Nepal -- Economic conditions , Panchayat -- Nepal
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/138716 , vital:37667
- Description: The principal objective of this thesis is to offer a critical analysis of the process of de-peasantisation in Nepal since 1950, with a particular focus on the capitalist neo-liberal restructuring of the economy beginning in the early 1990s. The analysis begins by tracing the legacy of feudal land practices and landholdings from the pre-1950 Rana and Shah dynasties. It was under these feudal dynasties that economic and political institutions of extraction first emerged, leading to a landlord-peasant agrarian economy in which peasants (often as tenants/sharecroppers and smallholders) were subordinate to the power nexus between feudal landlords and the ruling dynasties. After 1950, a window of democratic opening was soon interrupted by the formation of the party-less Panchayat system, which lasted from 1960 to 1990. In 1964, a major land reform measure was enacted under the Lands Act, with the goal of enhancing the security and livelihood of the peasantry. However, this process was met with significant resistance by feudal landlords, and actually led to deepening insecurity and the loss of land by peasants, with farmers belonging to lower castes and indigenous groups experiencing this with a greater degree of intensity. The overall result of this period was the beginnings of what is referred to in this study as de-peasantisation. This line of analysis shows that the institutions of extraction remained firmly in place even after the reforms of this period. Finally, the neo-liberal period, which was marked by land titling, the marketisation of land, and the commercialisation of agriculture, represents the late entry of capitalism into Nepal. This period saw the deepening and widening of the process of de-peasantisation, including further loss of peasants’ access to land and a general turn to wage-labour. In this regard, despite propagating the slogan ‘land to the tillers’, the major political parties in Nepal (including the Maoist party) have failed to defend the interests of the peasantry. Some progressive civil society groups have recently sought to do better, but there is also evidence of peasant organisations themselves seeking to resist and oppose the de-peasantisation effects of neo-liberal restructuring. This thesis thus considers the form and extent of de-peasantisation in Nepal, and some responses to it, over an extended period. A broad Marxist-based political economy perspective has been adopted in pursuing the principal thesis objective, but one which argues that there is a symbiotic relationship between economic and political power, such that the latter is not reducible to the former. The thesis draws upon original fieldwork in twenty districts of Nepal, including through the use of a survey, interviews, observations, case studies, and focus group discussions, thus combining both quantitative and qualitative research methods. Based on this fieldwork, it becomes clear that (i) there are major social, economic, and political forces behind the processes of de-peasantisation in the studied districts (and in Nepal more broadly), and that (ii) the Nepali peasantry is becoming increasingly landless, or land-short, and subject to processes of proletarianisation.
- Full Text:
- Date Issued: 2020
A framework for price tariffs in the costing structures of South African private hospitals
- Authors: Botha, Gideon
- Date: 2020
- Subjects: Hospitals, Proprietary
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/47489 , vital:40126
- Description: The increase of South African health care costs can be extrapolated into the global healthcare cost challenge, with various factors contributing to this problem. One of the factors viewed as being central to the rising cost of health care is the inability of health care provider organisations to accurately measure unit costs of resources used to treat a patient for their medical condition and patient outcomes. The measurement of an accurate unit cost and patient outcomes is imperative to improving value, which is seen as an improvement in outcomes for every rand spent. The determination of price tariffs and the price tariff payment model used to onward bill the price tariff for medical services have also been identified as having a central role in improving value in health care. In order for price tariffs to improve value, they should be reflective and be based on an accurate unit cost that reflects the cost of resources used to provide efficient and effective care for a patient’s medical condition. For the price tariff payment model to improve value, it needs to reward providers for delivering superior patient outcomes at a lower cost by making price tariffs contingent on achieving specified outcomes as well as incorporating performance payments or holdbacks based on outcomes achieved. This study provides a framework for price tariffs in the costing structures of South African private hospitals. Secondary research was conducted in the form of a comprehensive literature search in order to do an interpretative analysis of the strengths and weaknesses of the various combinations of unit costing models and price tariff payment models used to determine prices in private hospitals. The literature review was followed by primary research that involved three phases, all of which used a qualitative research approach. In Phase 1, primary data were collected using unobtrusive measures that consisted of a data request first, followed by unstructured interviews with representatives of Hospital A and Hospital B to obtain an analysis of the combinations of unit costing model and price tariff payment model used for a laparoscopic appendectomy. In Phase 2, data were collected by means of an unstructured interview with a surgeon describing a laparoscopic appendectomy procedure in detail and based on this process description, the approximate costs for the various resources that were sourced from different suppliers could be calculated. The data analysis and interpretation were done in three phases, with each phase having different research objectives. The data were first coded and then interpreted. In the first primary research phase, the combinations of unit costing models and price tariff payment models used by private Hospital A and Hospital B were evaluated. In the second phase, the recommended combination of unit costing model and price tariff payment model was applied to a hypothetical example and evaluated. In the final phase, based on the outcome of the first and second research phases, a combination of unit costing model and price tariff payment model for private hospitals was recommended. The results showed that the recommended combination of unit costing and price tariff payment model namely time-driven activity-based costing with the global fee price tariff payment model was the most appropriate to determine price tariffs in private hospitals when compared to the unit costing models and price tariff payment models used by Hospital A and Hospital B for a laparoscopic appendectomy. Furthermore, the recommended combination of unit costing model and price tariff payment model was found to be usable for the determination of price tariffs in the costing structures of private hospitals. The time-driven activity-based costing model and global fee price tariff payment model should be adopted or used as guidelines for determining price tariffs in private hospitals in South Africa. Price tariffs would be more transparent as they would reflect the actual resource cost of treating the patient and the resources used and treatment provided could then be assessed against the delivery value chain that charts the principal activities involved in a patient’s care for a medical condition to ensure that patient best-practice protocols are followed. The proposed framework enables the determination of price tariffs based on an accurate unit cost reflecting the actual resources used to provide efficient and effective care and also improve value for the patient.
- Full Text:
- Date Issued: 2020
- Authors: Botha, Gideon
- Date: 2020
- Subjects: Hospitals, Proprietary
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/47489 , vital:40126
- Description: The increase of South African health care costs can be extrapolated into the global healthcare cost challenge, with various factors contributing to this problem. One of the factors viewed as being central to the rising cost of health care is the inability of health care provider organisations to accurately measure unit costs of resources used to treat a patient for their medical condition and patient outcomes. The measurement of an accurate unit cost and patient outcomes is imperative to improving value, which is seen as an improvement in outcomes for every rand spent. The determination of price tariffs and the price tariff payment model used to onward bill the price tariff for medical services have also been identified as having a central role in improving value in health care. In order for price tariffs to improve value, they should be reflective and be based on an accurate unit cost that reflects the cost of resources used to provide efficient and effective care for a patient’s medical condition. For the price tariff payment model to improve value, it needs to reward providers for delivering superior patient outcomes at a lower cost by making price tariffs contingent on achieving specified outcomes as well as incorporating performance payments or holdbacks based on outcomes achieved. This study provides a framework for price tariffs in the costing structures of South African private hospitals. Secondary research was conducted in the form of a comprehensive literature search in order to do an interpretative analysis of the strengths and weaknesses of the various combinations of unit costing models and price tariff payment models used to determine prices in private hospitals. The literature review was followed by primary research that involved three phases, all of which used a qualitative research approach. In Phase 1, primary data were collected using unobtrusive measures that consisted of a data request first, followed by unstructured interviews with representatives of Hospital A and Hospital B to obtain an analysis of the combinations of unit costing model and price tariff payment model used for a laparoscopic appendectomy. In Phase 2, data were collected by means of an unstructured interview with a surgeon describing a laparoscopic appendectomy procedure in detail and based on this process description, the approximate costs for the various resources that were sourced from different suppliers could be calculated. The data analysis and interpretation were done in three phases, with each phase having different research objectives. The data were first coded and then interpreted. In the first primary research phase, the combinations of unit costing models and price tariff payment models used by private Hospital A and Hospital B were evaluated. In the second phase, the recommended combination of unit costing model and price tariff payment model was applied to a hypothetical example and evaluated. In the final phase, based on the outcome of the first and second research phases, a combination of unit costing model and price tariff payment model for private hospitals was recommended. The results showed that the recommended combination of unit costing and price tariff payment model namely time-driven activity-based costing with the global fee price tariff payment model was the most appropriate to determine price tariffs in private hospitals when compared to the unit costing models and price tariff payment models used by Hospital A and Hospital B for a laparoscopic appendectomy. Furthermore, the recommended combination of unit costing model and price tariff payment model was found to be usable for the determination of price tariffs in the costing structures of private hospitals. The time-driven activity-based costing model and global fee price tariff payment model should be adopted or used as guidelines for determining price tariffs in private hospitals in South Africa. Price tariffs would be more transparent as they would reflect the actual resource cost of treating the patient and the resources used and treatment provided could then be assessed against the delivery value chain that charts the principal activities involved in a patient’s care for a medical condition to ensure that patient best-practice protocols are followed. The proposed framework enables the determination of price tariffs based on an accurate unit cost reflecting the actual resources used to provide efficient and effective care and also improve value for the patient.
- Full Text:
- Date Issued: 2020
A gendered analysis of conditional cash based transfers: a case study of Puntland Technical Vocational Skills Training Programme, Somalia
- Authors: Chitombi, Rumbidzai
- Date: 2020
- Subjects: Puntland Technical Vocational Skills Training Programme , Transfer payments -- Somalia -- Case studies , Economic assistance, Domestic -- Somalia , Economic development -- Social aspects -- Somalia , Women -- Somalia -- Social conditions
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167335 , vital:41469
- Description: As part of the worldwide development system, conditional cash transfer (CCT) programmes have become an increasingly popular policy and development approach in seeking to address poverty, especially in developing countries. Under the CCT programmes, beneficiaries are given assistance in the form of either cash or cash vouchers after fulfilling certain obligations of the development programme, such as attending training, enacting proper health care, or ensuring regular school attendance of children. The programmes have been described as a ‘double-edged sword’ since they aim to address poverty and, at the same time, reduce reliance on government largesse. In this regard, they are seen as potentially effective, and more empowering, alternatives to more traditional social assistance programmes whereby poor people receive welfare assistance in the form of ‘in kind’ and ‘unconditional’ assistance, receiving this as either food or shelter commodities, and without having to meet any conditions in doing so. This ‘traditional’ way of assisting poor people has largely been criticised for creating a dependency syndrome amongst the beneficiaries. In certain cases, CCT programmes focus specifically on women, either in receiving the cash transfer or in meeting the conditions attached to the programme, or both. In this context, considerable debate exists in the scholarly literature about the effects of such CCT programmes on the situation and status of women, specifically in terms of possibly empowering women. While some scholars claim that these programmes enhance the human and financial assets of women, others argue that focusing specifically on women, and as care-givers within households, tends to reproduce gender-based inequalities and subordination. Since gender equality and female empowerment are now key issues in global development spheres, and at national levels, this thesis aims to contribute to literature on the effects of CCTs on gender and women’s empowerment. This is pursued by way of a gendered perspective on CCTs as a development methodology for empowering women with reference to Somalia, using the Puntland Technical Vocational Skills Training programme as a case study. This programme focused, in the main, on internally-displaced people in Somalia, with a particular emphasis on women in meeting the programme conditions (i.e. participating in a training programme) and in being the cash recipients. The study used both quantitative and qualitative approaches for data collection and analysis, focusing on sixty selected beneficiaries who participated in the Puntland Technical Vocational skills training programme in Somalia from 2013. The thesis examines the prevailing structures (including cultural dynamics and socio-economic factors) in Somalia which lead to women’s subordination, notably in the light of significant internal displacement because of war and conflict and the emergence of internally-displaced camps. On this basis, from a gendered perspective, there is a critical appraisal of the manner in which the Puntland CCT programme affected women’s subordinate status, including how it may have led to the restructuring of gendered relations at both household and community levels. In offering this appraisal with reference to the Puntland programme, the thesis argues that women’s subordination and, by extension, women’s empowerment, is multi-faceted, and that continuity and change along the dimensions of subordination is often uneven and contradictory. Further, as also demonstrated in the Puntland case study, women’s subordination (as a social totality) is not a totalising system, such that women regularly make use of gaps in the system as opportunities to enhance their well-being without confronting the totality of the system.
- Full Text:
- Date Issued: 2020
- Authors: Chitombi, Rumbidzai
- Date: 2020
- Subjects: Puntland Technical Vocational Skills Training Programme , Transfer payments -- Somalia -- Case studies , Economic assistance, Domestic -- Somalia , Economic development -- Social aspects -- Somalia , Women -- Somalia -- Social conditions
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167335 , vital:41469
- Description: As part of the worldwide development system, conditional cash transfer (CCT) programmes have become an increasingly popular policy and development approach in seeking to address poverty, especially in developing countries. Under the CCT programmes, beneficiaries are given assistance in the form of either cash or cash vouchers after fulfilling certain obligations of the development programme, such as attending training, enacting proper health care, or ensuring regular school attendance of children. The programmes have been described as a ‘double-edged sword’ since they aim to address poverty and, at the same time, reduce reliance on government largesse. In this regard, they are seen as potentially effective, and more empowering, alternatives to more traditional social assistance programmes whereby poor people receive welfare assistance in the form of ‘in kind’ and ‘unconditional’ assistance, receiving this as either food or shelter commodities, and without having to meet any conditions in doing so. This ‘traditional’ way of assisting poor people has largely been criticised for creating a dependency syndrome amongst the beneficiaries. In certain cases, CCT programmes focus specifically on women, either in receiving the cash transfer or in meeting the conditions attached to the programme, or both. In this context, considerable debate exists in the scholarly literature about the effects of such CCT programmes on the situation and status of women, specifically in terms of possibly empowering women. While some scholars claim that these programmes enhance the human and financial assets of women, others argue that focusing specifically on women, and as care-givers within households, tends to reproduce gender-based inequalities and subordination. Since gender equality and female empowerment are now key issues in global development spheres, and at national levels, this thesis aims to contribute to literature on the effects of CCTs on gender and women’s empowerment. This is pursued by way of a gendered perspective on CCTs as a development methodology for empowering women with reference to Somalia, using the Puntland Technical Vocational Skills Training programme as a case study. This programme focused, in the main, on internally-displaced people in Somalia, with a particular emphasis on women in meeting the programme conditions (i.e. participating in a training programme) and in being the cash recipients. The study used both quantitative and qualitative approaches for data collection and analysis, focusing on sixty selected beneficiaries who participated in the Puntland Technical Vocational skills training programme in Somalia from 2013. The thesis examines the prevailing structures (including cultural dynamics and socio-economic factors) in Somalia which lead to women’s subordination, notably in the light of significant internal displacement because of war and conflict and the emergence of internally-displaced camps. On this basis, from a gendered perspective, there is a critical appraisal of the manner in which the Puntland CCT programme affected women’s subordinate status, including how it may have led to the restructuring of gendered relations at both household and community levels. In offering this appraisal with reference to the Puntland programme, the thesis argues that women’s subordination and, by extension, women’s empowerment, is multi-faceted, and that continuity and change along the dimensions of subordination is often uneven and contradictory. Further, as also demonstrated in the Puntland case study, women’s subordination (as a social totality) is not a totalising system, such that women regularly make use of gaps in the system as opportunities to enhance their well-being without confronting the totality of the system.
- Full Text:
- Date Issued: 2020
A holistic approach in understanding the effects of dietary protein sources on the growth and reproductive development of farmed abalone, Haliotis midae
- Wu, Yu
- Authors: Wu, Yu
- Date: 2020
- Subjects: Abalones -- Nutrition , Abalones -- Reproduction , Abalones -- Growth , Abalone culture , Haliotis midae -- Nutrition , Haliotis midae -- Reproduction , Haliotis midae -- Growth , Haliotis midae fisheries
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167719 , vital:41506
- Description: The combination of fishmeal and soya in the formulated feed of farmed South African abalone, Haliotis midae, not only improved abalone growth, but also the sustainability of the compound diets by reducing the reliance on fishmeal. However, the presence of soya produced larger gonads compared to those of abalone fed kelp or single-source protein diets. There is an increasing drive to control sexual maturation and reduce undesirable spawning events in farmed abalone. However, the reasons for the reported effects of soya inclusion on the reproductive development of farmed H. midae remain unresolved. The aim of this research was to use a combination of techniques to contribute to the understanding of the relationship between growth, reproductive and nutritional physiology of farmed H. midae fed diets of varying protein sources. These techniques included stable isotope analysis (SIA), fatty acid analysis, gonad histological assessments and haemolymph sexsteroid hormone analysis. The objectives were to examine the allocation of protein and nutritional components to somatic and reproductive tissues. This study also included the first attempt to investigate the role that sex steroid hormones play during gametogenesis. Abalone (40 – 50 g abalone-1) were fed one of four diets: either a single-source protein-based diet, i.e., (1) fishmeal-only (FM) or (2) soya-only (S), or a combination diet of (3) fishmeal-soya (FM S) or (4) fishmeal-sunflower meal (FM SM). Sampling occurred in 45-day intervals over one year. Dietary protein source had an effect on the growth of abalone, with enhancements in growth linked to the combination of fishmeal and a plant-protein source. The fishmeal ingredient was the most utilised protein source throughout the temporal changes in protein allocation into somatic and reproductive tissue, followed by soya and then sunflower meal. The mean whole- body mass of abalone was significantly influenced by an interaction between time and dietary treatment, with average whole-body mass changing differently over time between treatments (RM-ANOVA, F(24, 96) = 2.13, p = 0.005). Overall, abalone that were fed FM S had higher mean whole-body mass values than abalone that were fed the single-protein based diets, while abalone that were fed FM SM were similar to animals from all dietary treatments (RMANOVA, F(3, 12) = 5.75, p = 0.01). Male abalone had significantly higher gonad bulk index (GBI) values compared to females (RM-ANOVA, F(1, 24) = 49.03, p < 0.001) and this was independent of dietary treatment. Within each sex, female abalone fed the FM S diet (15.92 ± 1.88 mm3 g-1) had significantly higher GBI values than abalone fed S (9.76 ± 1.08 mm3 g-1), while abalone fed FM (11.96 ± 1.71 mm3 g-1) and FM SM (11.90 ± 0.80 mm3 g-1) were similar to abalone from all other dietary treatments (Tukey’s HSD, p < 0.05). Male abalone fed the FM S (21.59 ± 2.10 mm3 g-1) and FM SM diet (19.30 ± 2.63 mm3 g-1) had similar GBI values and they were significantly higher than in abalone fed the S diet (14.74 ± 1.27 mm3 g-1), while abalone fed FM S had significantly higher GBI values than abalone that consumed the FM diet (15.08 ±1.63mm3 g-1) ( Tukey’s HSD, p < 0.05). Although sunflower meal was poorly utilised, it produced similar overall growth to abalone that were fed the FM S diets. Yet, feed conversion ratio values were significantly lower for abalone fed FM S (1.30 ± 0.13) compared to those in the other three treatments, with ratios ranging from 1.65 – 1.72 over the one-year. The fatty acid compositions of the somatic and gonadal tissues were similar between treatments (PERMANOVA, p = 0.21), while fatty acid composition was influenced by sampling day, tissue type and abalone sex (PERMANOVA, p < 0.05). The essential fatty acids (EFAs) eicosadienoic acid and a-linolenic acid were present in abalone tissue, but they were not detected in the diets, suggesting the important role that an alternate food source (e.g. farmed abalone also had access to diatoms) may have played and the ability that H. midae may have in converting long-chain polyunsaturated fatty acids from C18 precursors. A change in the abundance of EFAs in the gonad tissue during highest and lowest GBI values suggested that arachidonic, eicosapentaenoic, g-linolenic and linoleic acid were important in females, while eicosapentaenoic, eicosadienoic and a-linolenic acid were important for male reproductive development. Dietary protein sources had an effect on the frequency distribution of maturity stages, where females that were fed FM S produced more ripe gonads and more males that were fed FM SM contained testes that showed signs of ripeness over the one-year study. Although dietary protein influenced the sex steroid concentrations in females and males, exhibiting fluctuations throughout the one-year period, no distinct pattern linked to gametogenesis were observed. The results from this study illustrate: (1) the importance of conducting laboratory studies when implementing SIA and mixing models in aquaculture nutrition; (2) conducting nutritional studies on mature, grow-out abalone; and (3) assessing the importance of naturally occurring diatoms in their diet and their contribution to growth and reproduction. The novel contribution of this research towards abalone nutritional physiology, the implications of these findings to industry as well as potential considerations for future studies were addressed.
- Full Text:
- Date Issued: 2020
- Authors: Wu, Yu
- Date: 2020
- Subjects: Abalones -- Nutrition , Abalones -- Reproduction , Abalones -- Growth , Abalone culture , Haliotis midae -- Nutrition , Haliotis midae -- Reproduction , Haliotis midae -- Growth , Haliotis midae fisheries
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167719 , vital:41506
- Description: The combination of fishmeal and soya in the formulated feed of farmed South African abalone, Haliotis midae, not only improved abalone growth, but also the sustainability of the compound diets by reducing the reliance on fishmeal. However, the presence of soya produced larger gonads compared to those of abalone fed kelp or single-source protein diets. There is an increasing drive to control sexual maturation and reduce undesirable spawning events in farmed abalone. However, the reasons for the reported effects of soya inclusion on the reproductive development of farmed H. midae remain unresolved. The aim of this research was to use a combination of techniques to contribute to the understanding of the relationship between growth, reproductive and nutritional physiology of farmed H. midae fed diets of varying protein sources. These techniques included stable isotope analysis (SIA), fatty acid analysis, gonad histological assessments and haemolymph sexsteroid hormone analysis. The objectives were to examine the allocation of protein and nutritional components to somatic and reproductive tissues. This study also included the first attempt to investigate the role that sex steroid hormones play during gametogenesis. Abalone (40 – 50 g abalone-1) were fed one of four diets: either a single-source protein-based diet, i.e., (1) fishmeal-only (FM) or (2) soya-only (S), or a combination diet of (3) fishmeal-soya (FM S) or (4) fishmeal-sunflower meal (FM SM). Sampling occurred in 45-day intervals over one year. Dietary protein source had an effect on the growth of abalone, with enhancements in growth linked to the combination of fishmeal and a plant-protein source. The fishmeal ingredient was the most utilised protein source throughout the temporal changes in protein allocation into somatic and reproductive tissue, followed by soya and then sunflower meal. The mean whole- body mass of abalone was significantly influenced by an interaction between time and dietary treatment, with average whole-body mass changing differently over time between treatments (RM-ANOVA, F(24, 96) = 2.13, p = 0.005). Overall, abalone that were fed FM S had higher mean whole-body mass values than abalone that were fed the single-protein based diets, while abalone that were fed FM SM were similar to animals from all dietary treatments (RMANOVA, F(3, 12) = 5.75, p = 0.01). Male abalone had significantly higher gonad bulk index (GBI) values compared to females (RM-ANOVA, F(1, 24) = 49.03, p < 0.001) and this was independent of dietary treatment. Within each sex, female abalone fed the FM S diet (15.92 ± 1.88 mm3 g-1) had significantly higher GBI values than abalone fed S (9.76 ± 1.08 mm3 g-1), while abalone fed FM (11.96 ± 1.71 mm3 g-1) and FM SM (11.90 ± 0.80 mm3 g-1) were similar to abalone from all other dietary treatments (Tukey’s HSD, p < 0.05). Male abalone fed the FM S (21.59 ± 2.10 mm3 g-1) and FM SM diet (19.30 ± 2.63 mm3 g-1) had similar GBI values and they were significantly higher than in abalone fed the S diet (14.74 ± 1.27 mm3 g-1), while abalone fed FM S had significantly higher GBI values than abalone that consumed the FM diet (15.08 ±1.63mm3 g-1) ( Tukey’s HSD, p < 0.05). Although sunflower meal was poorly utilised, it produced similar overall growth to abalone that were fed the FM S diets. Yet, feed conversion ratio values were significantly lower for abalone fed FM S (1.30 ± 0.13) compared to those in the other three treatments, with ratios ranging from 1.65 – 1.72 over the one-year. The fatty acid compositions of the somatic and gonadal tissues were similar between treatments (PERMANOVA, p = 0.21), while fatty acid composition was influenced by sampling day, tissue type and abalone sex (PERMANOVA, p < 0.05). The essential fatty acids (EFAs) eicosadienoic acid and a-linolenic acid were present in abalone tissue, but they were not detected in the diets, suggesting the important role that an alternate food source (e.g. farmed abalone also had access to diatoms) may have played and the ability that H. midae may have in converting long-chain polyunsaturated fatty acids from C18 precursors. A change in the abundance of EFAs in the gonad tissue during highest and lowest GBI values suggested that arachidonic, eicosapentaenoic, g-linolenic and linoleic acid were important in females, while eicosapentaenoic, eicosadienoic and a-linolenic acid were important for male reproductive development. Dietary protein sources had an effect on the frequency distribution of maturity stages, where females that were fed FM S produced more ripe gonads and more males that were fed FM SM contained testes that showed signs of ripeness over the one-year study. Although dietary protein influenced the sex steroid concentrations in females and males, exhibiting fluctuations throughout the one-year period, no distinct pattern linked to gametogenesis were observed. The results from this study illustrate: (1) the importance of conducting laboratory studies when implementing SIA and mixing models in aquaculture nutrition; (2) conducting nutritional studies on mature, grow-out abalone; and (3) assessing the importance of naturally occurring diatoms in their diet and their contribution to growth and reproduction. The novel contribution of this research towards abalone nutritional physiology, the implications of these findings to industry as well as potential considerations for future studies were addressed.
- Full Text:
- Date Issued: 2020
A housing affordability and tenure of choice quantum deliverable model in South Africa
- Authors: Kabundu, Emmanuel Kizito
- Date: 2020
- Subjects: Housing -- Prices -- South Africa Housing -- Economic aspects -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/49606 , vital:41740
- Description: The aim of this research was to develop a model that practically determines the tenure of choice and affordability of households in South Africa, which will thus help towards informed decision making by analysts and housing officials. Presently, there is no clear systematic means (except for simplistic ratios) of determining the degree of the effect of changes in the housing market (such as implemented policies) on the tenure of choice and affordability decisions of households. The research set out to improve upon the usage of ratios by basing its analysis on the theoretical underpinnings of both user costs of occupancy and an assumption of endogeneity between tenure of choice and affordability. The research used the general household survey data from Statistics South Africa for the analysis and validation. Generalized joint binary regression (on assumption of endogeneity between tenure of choice and affordability) was used as a check against the user costs of occupancy modelling. An independent market analysis carried out showed that South Africa has consistently faced increasing problems of acute housing shortages and housing affordability. Never the less, apart from subsidy programs, the option to promote renting, coupled with use of innovative building technologies showed promise of significantly alleviating these problems. More living space is especially more vital than ever, amid the current crisis of COVID-19 pademic. Statistical tests indicated strong evidence suggesting that the developed user costs of occupancy model (dynamic tenure model) is reliable at correctly recovering the tenure statuses of the households, with its recovery rates being better than those of the regression model. Both models provided useful unique, but different insights into the housing market and also correctly predicted the behavioural patterns of South African housing markets, such as significantly worsening affordability, and a market that is biased towards home ownership. The analysis also showed that affordability and tenure of choice were significantly affected by locational factors, household characteristics (such as race and age of household head), and most significantly, the age of the household head (which is a proxy to household income). The research successfully met its goal of model building but also recognized the need to merge these two models (dynamic tenure model and the regression model) into one model for more comprehensive housing related analysis. The research also recognized a need to fully operationalize the optimization, Monte Carlo and parallelization modules in order to improve the practical usefulness and effectiveness of the model. The significance of the study is that it it underpins the basis for proper tenure and affordability analysis, by assuming endogeneity between the two (2), and provides a modelling framework based on these criteria, that are useful for meaningful housing market analysis.
- Full Text:
- Date Issued: 2020
- Authors: Kabundu, Emmanuel Kizito
- Date: 2020
- Subjects: Housing -- Prices -- South Africa Housing -- Economic aspects -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/49606 , vital:41740
- Description: The aim of this research was to develop a model that practically determines the tenure of choice and affordability of households in South Africa, which will thus help towards informed decision making by analysts and housing officials. Presently, there is no clear systematic means (except for simplistic ratios) of determining the degree of the effect of changes in the housing market (such as implemented policies) on the tenure of choice and affordability decisions of households. The research set out to improve upon the usage of ratios by basing its analysis on the theoretical underpinnings of both user costs of occupancy and an assumption of endogeneity between tenure of choice and affordability. The research used the general household survey data from Statistics South Africa for the analysis and validation. Generalized joint binary regression (on assumption of endogeneity between tenure of choice and affordability) was used as a check against the user costs of occupancy modelling. An independent market analysis carried out showed that South Africa has consistently faced increasing problems of acute housing shortages and housing affordability. Never the less, apart from subsidy programs, the option to promote renting, coupled with use of innovative building technologies showed promise of significantly alleviating these problems. More living space is especially more vital than ever, amid the current crisis of COVID-19 pademic. Statistical tests indicated strong evidence suggesting that the developed user costs of occupancy model (dynamic tenure model) is reliable at correctly recovering the tenure statuses of the households, with its recovery rates being better than those of the regression model. Both models provided useful unique, but different insights into the housing market and also correctly predicted the behavioural patterns of South African housing markets, such as significantly worsening affordability, and a market that is biased towards home ownership. The analysis also showed that affordability and tenure of choice were significantly affected by locational factors, household characteristics (such as race and age of household head), and most significantly, the age of the household head (which is a proxy to household income). The research successfully met its goal of model building but also recognized the need to merge these two models (dynamic tenure model and the regression model) into one model for more comprehensive housing related analysis. The research also recognized a need to fully operationalize the optimization, Monte Carlo and parallelization modules in order to improve the practical usefulness and effectiveness of the model. The significance of the study is that it it underpins the basis for proper tenure and affordability analysis, by assuming endogeneity between the two (2), and provides a modelling framework based on these criteria, that are useful for meaningful housing market analysis.
- Full Text:
- Date Issued: 2020
A novel, improved throughput bioassay for determining the delative speed of antimalarial drug action using fluorescent vitality probes
- Authors: Laming, Dustin
- Date: 2020
- Subjects: Plasmodium falciparum , Malaria -- Treatment -- Africa , Antimalarials , Malaria vaccine
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/139902 , vital:37810
- Description: Malaria is one of the most prevalent diseases in Africa and Plasmodium falciparum is widely accepted as the most virulent of the malaria parasite species, with a fatality rate of 15 – 20 % of reported cases of infection. While various treatments have been accepted into early stage clinical trials, there has been little progress towards a proven vaccine. Pending a long-term solution, endemic countries rely heavily on the development of innovative drugs that are not only efficacious but are also quick acting. Traditional methods of evaluating antimalarial killing speeds via morphological assessments are inherently flawed by tedious, subjective interpretations of the heterogenous parasite morphology encountered in routine parasite culture conditions. This has led to the introduction of alternative assay formats to determine how rapidly compounds act on parasites in vitro: a parasite reduction ratio (PRR) assay that measures the recovery of parasite cultures from drug exposure; determining the shift in IC50 values of compounds when dose-response assays are carried out for different time periods; a bioluminescence relative rate of kill (BRRoK) assay that compares the extent to which compounds reduce firefly luciferase activity in transgenic parasites. Recent whole cell in vitro screening efforts have resulted in the generation of chemically diverse compound libraries such as the Medicines for Malaria Venture’s Pathogen Box, which houses 125 novel compounds with in vitro antiplasmodial activity. Assessing the relative killing speeds of these compounds would aid prioritizing fast-acting compounds that can be exploited as starting points for further development. This study aimed to develop a bioassay using the calcein-acetoxymethyl and propidium iodide fluorescent vitality probes, which would allow the relative speed of drug action on Plasmodium falciparum malaria parasites to be assessed and ranked in relation to each other using a quantitative, improved throughput approach. Initially applied to human (HeLa) cells, the assay was used to compare the relative speeds of action of 3 potential anti-cancer compounds by fluorescence microscopy. Subsequently adapted to P. falciparum, the assay was able to rank the relative speeds of action of standard antimalarials by fluorescence microscopy and two flow cytometry formats. Application of a multiwell flow cytometer increased throughput and enabled the assessment of experimental compounds, which included a set of artemisinin analogs and 125 antimalarial compounds in the MMV Pathogen Box. The latter culminated in the identification of five rapidly parasiticidal compounds in relation to the other compounds in the library, which may act as benchmark references for future studies and form the basis of the next generation of fast acting antimalarials that could be used to combat modern, resistant malaria.
- Full Text:
- Date Issued: 2020
- Authors: Laming, Dustin
- Date: 2020
- Subjects: Plasmodium falciparum , Malaria -- Treatment -- Africa , Antimalarials , Malaria vaccine
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/139902 , vital:37810
- Description: Malaria is one of the most prevalent diseases in Africa and Plasmodium falciparum is widely accepted as the most virulent of the malaria parasite species, with a fatality rate of 15 – 20 % of reported cases of infection. While various treatments have been accepted into early stage clinical trials, there has been little progress towards a proven vaccine. Pending a long-term solution, endemic countries rely heavily on the development of innovative drugs that are not only efficacious but are also quick acting. Traditional methods of evaluating antimalarial killing speeds via morphological assessments are inherently flawed by tedious, subjective interpretations of the heterogenous parasite morphology encountered in routine parasite culture conditions. This has led to the introduction of alternative assay formats to determine how rapidly compounds act on parasites in vitro: a parasite reduction ratio (PRR) assay that measures the recovery of parasite cultures from drug exposure; determining the shift in IC50 values of compounds when dose-response assays are carried out for different time periods; a bioluminescence relative rate of kill (BRRoK) assay that compares the extent to which compounds reduce firefly luciferase activity in transgenic parasites. Recent whole cell in vitro screening efforts have resulted in the generation of chemically diverse compound libraries such as the Medicines for Malaria Venture’s Pathogen Box, which houses 125 novel compounds with in vitro antiplasmodial activity. Assessing the relative killing speeds of these compounds would aid prioritizing fast-acting compounds that can be exploited as starting points for further development. This study aimed to develop a bioassay using the calcein-acetoxymethyl and propidium iodide fluorescent vitality probes, which would allow the relative speed of drug action on Plasmodium falciparum malaria parasites to be assessed and ranked in relation to each other using a quantitative, improved throughput approach. Initially applied to human (HeLa) cells, the assay was used to compare the relative speeds of action of 3 potential anti-cancer compounds by fluorescence microscopy. Subsequently adapted to P. falciparum, the assay was able to rank the relative speeds of action of standard antimalarials by fluorescence microscopy and two flow cytometry formats. Application of a multiwell flow cytometer increased throughput and enabled the assessment of experimental compounds, which included a set of artemisinin analogs and 125 antimalarial compounds in the MMV Pathogen Box. The latter culminated in the identification of five rapidly parasiticidal compounds in relation to the other compounds in the library, which may act as benchmark references for future studies and form the basis of the next generation of fast acting antimalarials that could be used to combat modern, resistant malaria.
- Full Text:
- Date Issued: 2020
A personality-based surveillance model for Facebook apps
- Authors: Van der Schyff, Karl Izak
- Date: 2020
- Subjects: Facebook (Electronic resource) , Electronic surveillance -- Psychological aspects , Online social networks -- Psychological aspects , Social media -- Psychological aspects , Personality
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/145534 , vital:38447
- Description: The surveillance of data through the use of Facebook Apps is an ongoing and persistent problem that impacts millions of users. Nonetheless, limited research has been conducted investigating to what extent a Facebook user’s personality influences their awareness of such surveillance practices. Thus, to understand this situation better, the current study inductively developed four propositions from secondary data sources as part of a detailed content analysis. Spanning three search and analysis phases the content analysis led to the development of the research model. Guided by the propositions and research questions, a questionnaire was developed based on the relevant constructs prescribed by the Theory of Planned Behaviour. This questionnaire was used, and a total of 651 responses were collected from Facebook users over the age of 18 years old and residing in the United States of America. Primary data took place at both a univariate and multivariate level with a specific focus on the development of a structural model. Interpretation of the structural model revealed that out of all the Big Five personality traits, Conscientiousness exhibited the strongest relationship with information security awareness followed by Openness to Experience and Neuroticism, respectively. The results further indicated that the model constructs based on attitude, social norms and awareness significantly influenced the intended use of Facebook Apps. The study also contributes by indicating which personality traits are most vulnerable to Facebook App surveillance. For example, it was found that individuals high in Conscientiousness are the least vulnerable with individuals high in Extraversion being the most vulnerable. Since the results indicate that not all the personality traits are significantly related to the model constructs, additional factors may contribute to App surveillance in this context. Concerning this, factors such as user apathy, information privacy, privacy concerns, control and Facebook dependency are discussed as a means to argue why this might be the case.
- Full Text:
- Date Issued: 2020
- Authors: Van der Schyff, Karl Izak
- Date: 2020
- Subjects: Facebook (Electronic resource) , Electronic surveillance -- Psychological aspects , Online social networks -- Psychological aspects , Social media -- Psychological aspects , Personality
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/145534 , vital:38447
- Description: The surveillance of data through the use of Facebook Apps is an ongoing and persistent problem that impacts millions of users. Nonetheless, limited research has been conducted investigating to what extent a Facebook user’s personality influences their awareness of such surveillance practices. Thus, to understand this situation better, the current study inductively developed four propositions from secondary data sources as part of a detailed content analysis. Spanning three search and analysis phases the content analysis led to the development of the research model. Guided by the propositions and research questions, a questionnaire was developed based on the relevant constructs prescribed by the Theory of Planned Behaviour. This questionnaire was used, and a total of 651 responses were collected from Facebook users over the age of 18 years old and residing in the United States of America. Primary data took place at both a univariate and multivariate level with a specific focus on the development of a structural model. Interpretation of the structural model revealed that out of all the Big Five personality traits, Conscientiousness exhibited the strongest relationship with information security awareness followed by Openness to Experience and Neuroticism, respectively. The results further indicated that the model constructs based on attitude, social norms and awareness significantly influenced the intended use of Facebook Apps. The study also contributes by indicating which personality traits are most vulnerable to Facebook App surveillance. For example, it was found that individuals high in Conscientiousness are the least vulnerable with individuals high in Extraversion being the most vulnerable. Since the results indicate that not all the personality traits are significantly related to the model constructs, additional factors may contribute to App surveillance in this context. Concerning this, factors such as user apathy, information privacy, privacy concerns, control and Facebook dependency are discussed as a means to argue why this might be the case.
- Full Text:
- Date Issued: 2020
A psychobiographical case study: Amelia Dyer in a search for glory
- Authors: April, Heather
- Date: 2020
- Subjects: Serial murderers--Psychology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50857 , vital:43008
- Description: The study is a psychobiographical case study based on the life of a Victorian baby farmer Amelia Dyer (1837-1896). She was executed for the murder of babies who were placed in her care over a period of 30 years. Psychobiography is a qualitative method of enquiry which explores the life of a unique individual subject through the lens of a psychological theory for the purpose of creating a coherent psychological case study. The psychoanalytic theoretical lens of Karen Horney was used to trace the evolution of Amelia Dyer’s sense of self within the Victorian culture of respectability. Baby farming referred to an unregulated business of adoption and fostering of infants, mostly illegitimate infants for a fee. Insufficient social structures and support for unwed mothers and children encouraged the business practice as women had very little choice for childcare. Baby farming was open to abuse and exploitation and hundreds of babies lost their lives due to insufficient care or infanticide. Amelia Dyer showed special talents and creativity from a young age, was ambitious and wanted to be self-reliant in a culture that did not provide women with opportunities to live out their ambitions. Baby farming became a business venture for her in the early stages of her life which later evolved into sadistic abuse and murder of the infants. Her evolution from a creative and hardworking young girl to a sadistic murderer of children is what qualifies her as a suitable subject for the exploration of Karen Horney’s dynamic theory of neuroses and the development of the neurotic self within culture. Extensive biographical data was collected and processed into salient themes. The study integrates the theory of Karen Horney, the life experiences of Amelia Dyer and Victorian respectability and demonstrates the value of using psychobiography as the method of inquiry into the exploration of the unique individual. The findings of the study demonstrated that Amelia Dyer and her social context were inextricably bound by a vicious cycle of psychic and emotional vi conflicts related to fear, control and self-hatred by the internalization of gender stereotypes and norms. The contribution of the study as a whole rests with its demonstration of the value of a holistic and reflexive exploration of the unique individual woman. It demonstrates the value of Horney’s in-depth theoretical understanding of the ambivalent core of selfhood that lies behind observable acts of behavior. The study as a whole contributes towards building upon holistic and integrative therapeutic frameworks in the understanding of diversity amongst women and mothers in culture.
- Full Text:
- Date Issued: 2020
- Authors: April, Heather
- Date: 2020
- Subjects: Serial murderers--Psychology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50857 , vital:43008
- Description: The study is a psychobiographical case study based on the life of a Victorian baby farmer Amelia Dyer (1837-1896). She was executed for the murder of babies who were placed in her care over a period of 30 years. Psychobiography is a qualitative method of enquiry which explores the life of a unique individual subject through the lens of a psychological theory for the purpose of creating a coherent psychological case study. The psychoanalytic theoretical lens of Karen Horney was used to trace the evolution of Amelia Dyer’s sense of self within the Victorian culture of respectability. Baby farming referred to an unregulated business of adoption and fostering of infants, mostly illegitimate infants for a fee. Insufficient social structures and support for unwed mothers and children encouraged the business practice as women had very little choice for childcare. Baby farming was open to abuse and exploitation and hundreds of babies lost their lives due to insufficient care or infanticide. Amelia Dyer showed special talents and creativity from a young age, was ambitious and wanted to be self-reliant in a culture that did not provide women with opportunities to live out their ambitions. Baby farming became a business venture for her in the early stages of her life which later evolved into sadistic abuse and murder of the infants. Her evolution from a creative and hardworking young girl to a sadistic murderer of children is what qualifies her as a suitable subject for the exploration of Karen Horney’s dynamic theory of neuroses and the development of the neurotic self within culture. Extensive biographical data was collected and processed into salient themes. The study integrates the theory of Karen Horney, the life experiences of Amelia Dyer and Victorian respectability and demonstrates the value of using psychobiography as the method of inquiry into the exploration of the unique individual. The findings of the study demonstrated that Amelia Dyer and her social context were inextricably bound by a vicious cycle of psychic and emotional vi conflicts related to fear, control and self-hatred by the internalization of gender stereotypes and norms. The contribution of the study as a whole rests with its demonstration of the value of a holistic and reflexive exploration of the unique individual woman. It demonstrates the value of Horney’s in-depth theoretical understanding of the ambivalent core of selfhood that lies behind observable acts of behavior. The study as a whole contributes towards building upon holistic and integrative therapeutic frameworks in the understanding of diversity amongst women and mothers in culture.
- Full Text:
- Date Issued: 2020
A psychobiography of Viktor Emil Frankl
- Authors: Bushkin, Hanan
- Date: 2020
- Subjects: Frankl, Viktor Emil
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/46440 , vital:39566
- Description: The first study conducted in South Africa of a prominent figure traces back as far as 1939. Since then, extensive research has been done in the field of psychobiography, resulting in a growing interest in this field and evolving into an established research genre in South Africa. Despite the increase in the use of psychobiographies as a research approach internationally and specifically in South Africa, its use is still considered relatively under-utilised and, therefore, the pursuit of further development of psychobiographies in South Africa is required. In light of South Africa’s effort to promote and advance the use of psychobiographies, South African researchers may be motivated to continue studying significant and exceptional lives in South Africa and abroad. Viktor Frankl was selected for this study based on his uniqueness, significance and his interesting life. He is also considered an exceptional individual who has shaped modern psychological thinking. Frankl had written over 40 books on his theory and many studies have been conducted based on his existential theory. Frankl’s contribution to the academic world has been recognised and acknowledged by significant institutions through his own and others’ research. Although much has been written on the life and work of Frankl, none of the literature utilises specific psychological focus and no psychobiographical study of the life of Frankl exists. Therefore, the researcher selected Frankl as the subject for this psychobiography through purposive sampling. The aim of the study was to provide a psychological exploration and description of Frankl’s life against the backdrop of his socio-cultural context. In order to achieve this aim, the researcher employed two psychological frameworks to guide in the description and exploration of his life. The psychological frameworks included Levinson’s life structure theory of adult development and Frankl’s existential theory. The study aimed to describe Frankl’s development with the use of Levinson’s theory while describing how he attained meaning in his life with the use of his own existential theory. Due to the exploratory-descriptive nature of this study, the objective fell within the inductive research approach. The researcher utilised a systematic coding method to arrange the data. The theoretical framework of Levinson’s life structure theory guided the coding system, as well as the key concepts of Frankl’s existential theory. In addition, the researcher utilised Alexander’s guidelines for the extraction of salient data, together with McAdam’s methods and recommendations for managing the data. Lastly, the researcher followed the 12-step method of conducting a psychobiography, as proposed by Du Plessis. Findings from this study found a correlation between Frankl’s life and the eras and transitional periods as theorised by Levinson’s theory. The findings of this study, therefore, support the use of Levinson’s theory with regards to the time frames and its use in understanding Frankl’s development. Also, the researcher found that Levinson’s theory was useful in understanding Frankl’s personality development within his context throughout his lifespan. With regards to Frankl’s existential theory, the researcher found that the use of the theory was suitable in understanding Frankl’s search for meaning. Frankl’s concepts of freedom of will, will to meaning, meaning of life, existential vacuum, supra-meaning, dimensional ontology, the three triads and noö-dynamics assisted in explaining Frankl’s drive to find meaning in his life, take responsibility to attain such meaning and to strive for transcendence beyond his suffering. The researcher found Frankl’s theory useful in explaining his drive, motives, needs and patterns of behaviour within this context. The holistic and integrative approach of the study allowed for an in-depth exploration and description of Frankl’s life and development within his socio-historical context. In addition to contributing to the existing body of knowledge on Frankl, his life and his theory, the study also contributed to the growing field of psychobiographical research. The study acknowledged and highlighted that further in-depth examination of the lives of extraordinary personalities could significantly contribute to psychobiographical studies. Based on the psychological frameworks used to explore and describe Frankl’s life, recommendations are made for future research.
- Full Text:
- Date Issued: 2020
- Authors: Bushkin, Hanan
- Date: 2020
- Subjects: Frankl, Viktor Emil
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/46440 , vital:39566
- Description: The first study conducted in South Africa of a prominent figure traces back as far as 1939. Since then, extensive research has been done in the field of psychobiography, resulting in a growing interest in this field and evolving into an established research genre in South Africa. Despite the increase in the use of psychobiographies as a research approach internationally and specifically in South Africa, its use is still considered relatively under-utilised and, therefore, the pursuit of further development of psychobiographies in South Africa is required. In light of South Africa’s effort to promote and advance the use of psychobiographies, South African researchers may be motivated to continue studying significant and exceptional lives in South Africa and abroad. Viktor Frankl was selected for this study based on his uniqueness, significance and his interesting life. He is also considered an exceptional individual who has shaped modern psychological thinking. Frankl had written over 40 books on his theory and many studies have been conducted based on his existential theory. Frankl’s contribution to the academic world has been recognised and acknowledged by significant institutions through his own and others’ research. Although much has been written on the life and work of Frankl, none of the literature utilises specific psychological focus and no psychobiographical study of the life of Frankl exists. Therefore, the researcher selected Frankl as the subject for this psychobiography through purposive sampling. The aim of the study was to provide a psychological exploration and description of Frankl’s life against the backdrop of his socio-cultural context. In order to achieve this aim, the researcher employed two psychological frameworks to guide in the description and exploration of his life. The psychological frameworks included Levinson’s life structure theory of adult development and Frankl’s existential theory. The study aimed to describe Frankl’s development with the use of Levinson’s theory while describing how he attained meaning in his life with the use of his own existential theory. Due to the exploratory-descriptive nature of this study, the objective fell within the inductive research approach. The researcher utilised a systematic coding method to arrange the data. The theoretical framework of Levinson’s life structure theory guided the coding system, as well as the key concepts of Frankl’s existential theory. In addition, the researcher utilised Alexander’s guidelines for the extraction of salient data, together with McAdam’s methods and recommendations for managing the data. Lastly, the researcher followed the 12-step method of conducting a psychobiography, as proposed by Du Plessis. Findings from this study found a correlation between Frankl’s life and the eras and transitional periods as theorised by Levinson’s theory. The findings of this study, therefore, support the use of Levinson’s theory with regards to the time frames and its use in understanding Frankl’s development. Also, the researcher found that Levinson’s theory was useful in understanding Frankl’s personality development within his context throughout his lifespan. With regards to Frankl’s existential theory, the researcher found that the use of the theory was suitable in understanding Frankl’s search for meaning. Frankl’s concepts of freedom of will, will to meaning, meaning of life, existential vacuum, supra-meaning, dimensional ontology, the three triads and noö-dynamics assisted in explaining Frankl’s drive to find meaning in his life, take responsibility to attain such meaning and to strive for transcendence beyond his suffering. The researcher found Frankl’s theory useful in explaining his drive, motives, needs and patterns of behaviour within this context. The holistic and integrative approach of the study allowed for an in-depth exploration and description of Frankl’s life and development within his socio-historical context. In addition to contributing to the existing body of knowledge on Frankl, his life and his theory, the study also contributed to the growing field of psychobiographical research. The study acknowledged and highlighted that further in-depth examination of the lives of extraordinary personalities could significantly contribute to psychobiographical studies. Based on the psychological frameworks used to explore and describe Frankl’s life, recommendations are made for future research.
- Full Text:
- Date Issued: 2020
A reappraisal of the origin of the Hotazel Fe-Mn Formation in an evolving early Earth system through the application of mineral-specific geochemistry, speciation techniques and stable isotope systematics
- Authors: Mhlanga, Xolane Reginald
- Date: 2020
- Subjects: Manganese ores -- South Africa -- Hotazel , Manganese ores -- Geology , Iron ores -- South Africa -- Hotazel , Iron ores -- Geology , Geochemistry -- South Africa -- Hotazel , Isotope geology -- South Africa -- Hotazel , Geology, Stratigraphic -- Archaean , Geology, Stratigraphic -- Proterozoic , Transvaal Supergroup (South Africa) , Great Oxidation Event
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/146123 , vital:38497
- Description: Marine chemical sediments such as Banded Iron Formations deposited during the Archean-Palaeoproterozoic are studied extensively because they represent a period in the development of the Earth’s early history where the atmospheric O₂ content was below the present levels (PAL) of 21%. Prior to the Great Oxidation Event (GOE) at ca. 2.4 Ga, highly ferruginous and anoxic marine environments were dominated by extensive BIF deposition such as that of the Griqualand West Basin of the Transvaal Supergroup in South Africa. This basin is also thought to record the transition into the first rise of atmospheric O₂ in our planet, from the Koegas Subgroup to the Hotazel Formation dated at ca. 2.43 Ga (Gumsley et al., 2017). Two drill cores from the north eastern part of the Kalahari Manganese Field characterized by a well-preserved and complete intersection of the cyclic Mn-Fe Hotazel Formation were studied at a high resolution (sampled at approximately one-meter interval). Such high-resolution approach is being employed for the first time in this project, capturing in detail the three manganese rich layers intercalated with BIF and the transitions between these lithofacies. The micro-banded BIF is made up of three major phases, namely Fe-Ca-Mg carbonates (ankerite, siderite and calcite), magnetite, and silicates (chert and minor Fe-silicates); laminated transitional lutite consist of mainly hematite, chert and Mn-carbonates, whereas the manganese ore layers are made up of mostly calcic carbonates (Mn-calcite and Ca-kutnahorite) in the form of laminations and ovoids, while Mn-silicates include dominant braunite and lesser friedelite. All three lithofacies are very fine grained (sub-mm scale) and so petrographic and mineralogical observations were obtained mostly through scanning electron microscope analysis for detailed textural relationships with focus on the carbonate fraction. Bulk geochemical studies of the entire stratigraphy of the Hotazel Formation have previously provided great insights into the cyclic nature of the deposit but have not adequately considered the potential of the carbonate fraction of the rocks as a valuable proxy for understanding the chemistry of the primary depositional environment and insights into the redox processes that were at play. This is because these carbonates have always been attributed to diagenetic processes below the sediment-water interface such as microbially-mediated dissimilatory iron/manganese reduction (DIR/DMR) where the precursor/primary Fe-Mn oxyhydroxides have been reduced to result in the minerals observed today. The carbonate fraction of the BIF is made up of ankerite and siderite which co-exist in a chert matrix as anhedral to subhedral grains with no apparent replacement textures. This suggests co-precipitation of the two species which is at apparent odds with classic diagenetic models. Similarly, Mn-carbonates in the hematite lutite and manganese ore (Mn-calcite, kutnahorite, and minor rhodocrosite) co-exist in laminae and ovoids with no textures observed that would suggest an obvious sequential mode of formation during diagenesis. In this light, a carbonate-specific geochemical analysis based on the sequential Fe extraction technique of Poulton and Canfield (2005) was employed to decipher further the cyclic nature of the Hotazel Formation and its primary versus diagenetic controls. Results from the carbonate fraction analysis of the three lithofacies show a clear fractionation of iron and manganese during primary – rather than diagenetic - carbonate precipitation, suggesting a decoupling between DIR and DMR which is ultimately interpreted to have taken place in the water column. Bulk-rock concentration results for minor and trace elements such as Zr, Ti, Sc and Al have been used for the determination of either siliciclastic or volcanic detrital inputs as they are generally immobile in most natural aqueous solutions. These elements are in very low concentrations in all three lithofacies suggesting that the depositional environment had vanishingly small contributions from terrigenous or volcanic detritus. In terms of redox-sensitive transition metals, only Mo and Co appear to show an affinity for high Mn facies in the Hotazel sequence. Cobalt in particular attains a very low abundance in the Hotazel BIF layers at an average of ~ 4 ppm. This is similar to average pre-GOE BIF in South Africa and worldwide. Maxima in Co abundance are associated with transitional hematite lutite and Mn ore layers, but maxima over 100ppm are seen in within the hematite lutite and not within the Mn ore proper where maxima in Mn are recorded. This suggests a clear and direct association with the hematite fraction in the rocks, which is modally much higher in the lutites but drops substantially in the Mn layers themselves. The similarities of bulk-rock BIF and modern-day seawater REE patterns has been used as a key argument for primary controls in REE behaviour and minimal diagenetic modification. Likewise, the three lithofacies of the Hotazel Formation analysed in this study all share similar characteristics with a clear seawater signal through gentle positive slopes in the normalised abundance of LREE versus HREE. Negative Ce anomalies prevail in the entire sample set analysed, which has been interpreted before as a proxy for oxic seawater conditions. However, positive Ce anomalies that are traditionally linked to scavenging and deposition of primary tetravalent Mn oxyhydroxides (e.g., as observed in modern day ferromanganese nodules) are completely absent from the current dataset. The lack of a positive Ce anomaly in the manganese ore and peak Co association with ferric oxides and not with peak Mn, suggests that primary deposition must have occurred within an environment that was not fully oxidizing with respect to manganese. The use of stable isotopes (i.e., C and Fe) was employed to gain insights into redox processes, whether these are thought to have happened below the sediment-water interface or in contemporaneous seawater. At a small scale, all lithofacies of the Hotazel Formation record bulk-rock δ¹³C values that are low and essentially invariant about the average value of -9.5 per mil. This is independent of sharp variations in overall modal mineralogy, relative carbonate abundance and carbonate chemistry, which is clearly difficult to reconcile with in-situ diagenetic processes that predict highly variable δ¹³C signals in response to complex combinations of precursor sediment mineralogy, pore-fluid chemistry, organic carbon supply and open vs closed system diagenesis. At a stratigraphic scale, the carbonate δ¹³C (-5 to -13‰) variations between the different lithologies could instead represent temporal changes in water-column chemistry against well-developed physico-chemical gradients, depth of deposition and biological processes. The low iron isotope values recorded in the hematite lutite and manganese ore samples can be attributed to fractionation effects of initial oxidation of ferrous iron to form Fe-oxyhydroxides in the shallow parts of the basin, from an already isotopically highly depleted aqueous Fe-pool as proposed previously. The slightly higher but still negative bulk-rock δ⁵⁶Fe values of the host BIF can be attributed to water-column Fe isotopic effects at deeper levels between primary Fe oxyhydroxides and an isotopically heavier Fe(II) pool, which was subsequently preserved during diagenetic recrystallization. All above findings were combined into a conceptual model of deposition for the three different lithologies of the Hotazel Formation. The model predicts that free molecular oxygen must have been present within the shallow oceanic environment and implicates both Mn and Fe as active redox “players” compared to classic models that apply to the origin of worldwide BIF prior to the GOE. The deposition of the Hotazel strata is interpreted to have occurred through the following three stages: (1) BIF deposition occurred in a relatively deep oceanic environment above the Ongeluk lavas during marine transgression, where a redoxcline and seawater stratification separated hydrothermally sourced iron and manganese, in response to an active Mn-shuttle mechanism linked to Mn redox cycling. Abundant ferrous iron must have been oxidized by available oxygen but also by oxidised Mn species (MnOOH) and possibly even some soluble Mn(III) complexes. Through this process, Mn(III) was being effectively reduced back into solution along with cobalt(III), as Mn(II) and Co(II) respectively, thus creating maxima in their concentrations. A drawdown of Fe(OH)₃ particles was therefore the only net precipitation mechanism at this stage. Carbonate species of Fe and the abundant magnetite would possibly have formed by reaction between the ferric hydroxides and the deeper Fe(II) pool, while organic matter would also have reacted in the water-column via DIR, accounting for the low δ¹³C signature of Fe carbonate minerals. (2) Hematite lutite formation would have occurred at a relatively shallower environment during marine regression. At this stage, reductive cycling of Fe was minimal in the absence of a deeper Fe(II) reservoir reacting with the ferric primary precipitates. Therefore, DIR progressively gave way to manganese reduction and organic carbon oxidation (DMR), which reduced MnOOH to form Mn(II)-rich carbonates in the form of kutnahorite and Mn-calcite. Co-bearing Fe(OH)₃ would have precipitated and was ultimately preserved as Co-bearing hematite during diagenesis. (3) Deposition of manganese-rich sediment occurred at even shallower oceanic depths (maximum regression) where aerobic organic carbon oxidation replaced DMR, resulting in Ca-rich carbonates such as Mn-bearing calcite and Ca-kutnahorite, yet with a low carbon isotope signature recording aerobic conditions of organic carbon cycling. Mn(III) reduction at this stage was curtailed, leading to massive precipitation of MnOOH which was diagenetically transformed into braunite and friedelite. Simultaneous precipitation of Co-bearing Fe(OH)₃ would have continued but at much more subdued rates. Repeated transgressive-regressive cycles resulted in the cyclic BIF-hematite lutite- manganese ore nature of the Hotazel Formation in an oxidized oceanic environment at the onset of the Great Oxidation Event, which was nonetheless never oxic enough to drive Mn(II) oxidation fully to its tetravalent state. The mineralogy and species-specific geochemistry of the Hotazel strata, and more specifically the carbonate fraction thereof, appear to faithfully capture the chemistry of the primary depositional environment in a progressively evolving Earth System. This project opens the door for more studies focusing on better constraining primary versus diagenetic depositional 2020 Hotazel Fe and Mn deposition mechanisms of iron and manganese during the period leading up to the GOE, and possibly re-defining the significance of Fe and Mn as invaluable redox proxies in a rapidly changing planet.
- Full Text:
- Date Issued: 2020
- Authors: Mhlanga, Xolane Reginald
- Date: 2020
- Subjects: Manganese ores -- South Africa -- Hotazel , Manganese ores -- Geology , Iron ores -- South Africa -- Hotazel , Iron ores -- Geology , Geochemistry -- South Africa -- Hotazel , Isotope geology -- South Africa -- Hotazel , Geology, Stratigraphic -- Archaean , Geology, Stratigraphic -- Proterozoic , Transvaal Supergroup (South Africa) , Great Oxidation Event
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/146123 , vital:38497
- Description: Marine chemical sediments such as Banded Iron Formations deposited during the Archean-Palaeoproterozoic are studied extensively because they represent a period in the development of the Earth’s early history where the atmospheric O₂ content was below the present levels (PAL) of 21%. Prior to the Great Oxidation Event (GOE) at ca. 2.4 Ga, highly ferruginous and anoxic marine environments were dominated by extensive BIF deposition such as that of the Griqualand West Basin of the Transvaal Supergroup in South Africa. This basin is also thought to record the transition into the first rise of atmospheric O₂ in our planet, from the Koegas Subgroup to the Hotazel Formation dated at ca. 2.43 Ga (Gumsley et al., 2017). Two drill cores from the north eastern part of the Kalahari Manganese Field characterized by a well-preserved and complete intersection of the cyclic Mn-Fe Hotazel Formation were studied at a high resolution (sampled at approximately one-meter interval). Such high-resolution approach is being employed for the first time in this project, capturing in detail the three manganese rich layers intercalated with BIF and the transitions between these lithofacies. The micro-banded BIF is made up of three major phases, namely Fe-Ca-Mg carbonates (ankerite, siderite and calcite), magnetite, and silicates (chert and minor Fe-silicates); laminated transitional lutite consist of mainly hematite, chert and Mn-carbonates, whereas the manganese ore layers are made up of mostly calcic carbonates (Mn-calcite and Ca-kutnahorite) in the form of laminations and ovoids, while Mn-silicates include dominant braunite and lesser friedelite. All three lithofacies are very fine grained (sub-mm scale) and so petrographic and mineralogical observations were obtained mostly through scanning electron microscope analysis for detailed textural relationships with focus on the carbonate fraction. Bulk geochemical studies of the entire stratigraphy of the Hotazel Formation have previously provided great insights into the cyclic nature of the deposit but have not adequately considered the potential of the carbonate fraction of the rocks as a valuable proxy for understanding the chemistry of the primary depositional environment and insights into the redox processes that were at play. This is because these carbonates have always been attributed to diagenetic processes below the sediment-water interface such as microbially-mediated dissimilatory iron/manganese reduction (DIR/DMR) where the precursor/primary Fe-Mn oxyhydroxides have been reduced to result in the minerals observed today. The carbonate fraction of the BIF is made up of ankerite and siderite which co-exist in a chert matrix as anhedral to subhedral grains with no apparent replacement textures. This suggests co-precipitation of the two species which is at apparent odds with classic diagenetic models. Similarly, Mn-carbonates in the hematite lutite and manganese ore (Mn-calcite, kutnahorite, and minor rhodocrosite) co-exist in laminae and ovoids with no textures observed that would suggest an obvious sequential mode of formation during diagenesis. In this light, a carbonate-specific geochemical analysis based on the sequential Fe extraction technique of Poulton and Canfield (2005) was employed to decipher further the cyclic nature of the Hotazel Formation and its primary versus diagenetic controls. Results from the carbonate fraction analysis of the three lithofacies show a clear fractionation of iron and manganese during primary – rather than diagenetic - carbonate precipitation, suggesting a decoupling between DIR and DMR which is ultimately interpreted to have taken place in the water column. Bulk-rock concentration results for minor and trace elements such as Zr, Ti, Sc and Al have been used for the determination of either siliciclastic or volcanic detrital inputs as they are generally immobile in most natural aqueous solutions. These elements are in very low concentrations in all three lithofacies suggesting that the depositional environment had vanishingly small contributions from terrigenous or volcanic detritus. In terms of redox-sensitive transition metals, only Mo and Co appear to show an affinity for high Mn facies in the Hotazel sequence. Cobalt in particular attains a very low abundance in the Hotazel BIF layers at an average of ~ 4 ppm. This is similar to average pre-GOE BIF in South Africa and worldwide. Maxima in Co abundance are associated with transitional hematite lutite and Mn ore layers, but maxima over 100ppm are seen in within the hematite lutite and not within the Mn ore proper where maxima in Mn are recorded. This suggests a clear and direct association with the hematite fraction in the rocks, which is modally much higher in the lutites but drops substantially in the Mn layers themselves. The similarities of bulk-rock BIF and modern-day seawater REE patterns has been used as a key argument for primary controls in REE behaviour and minimal diagenetic modification. Likewise, the three lithofacies of the Hotazel Formation analysed in this study all share similar characteristics with a clear seawater signal through gentle positive slopes in the normalised abundance of LREE versus HREE. Negative Ce anomalies prevail in the entire sample set analysed, which has been interpreted before as a proxy for oxic seawater conditions. However, positive Ce anomalies that are traditionally linked to scavenging and deposition of primary tetravalent Mn oxyhydroxides (e.g., as observed in modern day ferromanganese nodules) are completely absent from the current dataset. The lack of a positive Ce anomaly in the manganese ore and peak Co association with ferric oxides and not with peak Mn, suggests that primary deposition must have occurred within an environment that was not fully oxidizing with respect to manganese. The use of stable isotopes (i.e., C and Fe) was employed to gain insights into redox processes, whether these are thought to have happened below the sediment-water interface or in contemporaneous seawater. At a small scale, all lithofacies of the Hotazel Formation record bulk-rock δ¹³C values that are low and essentially invariant about the average value of -9.5 per mil. This is independent of sharp variations in overall modal mineralogy, relative carbonate abundance and carbonate chemistry, which is clearly difficult to reconcile with in-situ diagenetic processes that predict highly variable δ¹³C signals in response to complex combinations of precursor sediment mineralogy, pore-fluid chemistry, organic carbon supply and open vs closed system diagenesis. At a stratigraphic scale, the carbonate δ¹³C (-5 to -13‰) variations between the different lithologies could instead represent temporal changes in water-column chemistry against well-developed physico-chemical gradients, depth of deposition and biological processes. The low iron isotope values recorded in the hematite lutite and manganese ore samples can be attributed to fractionation effects of initial oxidation of ferrous iron to form Fe-oxyhydroxides in the shallow parts of the basin, from an already isotopically highly depleted aqueous Fe-pool as proposed previously. The slightly higher but still negative bulk-rock δ⁵⁶Fe values of the host BIF can be attributed to water-column Fe isotopic effects at deeper levels between primary Fe oxyhydroxides and an isotopically heavier Fe(II) pool, which was subsequently preserved during diagenetic recrystallization. All above findings were combined into a conceptual model of deposition for the three different lithologies of the Hotazel Formation. The model predicts that free molecular oxygen must have been present within the shallow oceanic environment and implicates both Mn and Fe as active redox “players” compared to classic models that apply to the origin of worldwide BIF prior to the GOE. The deposition of the Hotazel strata is interpreted to have occurred through the following three stages: (1) BIF deposition occurred in a relatively deep oceanic environment above the Ongeluk lavas during marine transgression, where a redoxcline and seawater stratification separated hydrothermally sourced iron and manganese, in response to an active Mn-shuttle mechanism linked to Mn redox cycling. Abundant ferrous iron must have been oxidized by available oxygen but also by oxidised Mn species (MnOOH) and possibly even some soluble Mn(III) complexes. Through this process, Mn(III) was being effectively reduced back into solution along with cobalt(III), as Mn(II) and Co(II) respectively, thus creating maxima in their concentrations. A drawdown of Fe(OH)₃ particles was therefore the only net precipitation mechanism at this stage. Carbonate species of Fe and the abundant magnetite would possibly have formed by reaction between the ferric hydroxides and the deeper Fe(II) pool, while organic matter would also have reacted in the water-column via DIR, accounting for the low δ¹³C signature of Fe carbonate minerals. (2) Hematite lutite formation would have occurred at a relatively shallower environment during marine regression. At this stage, reductive cycling of Fe was minimal in the absence of a deeper Fe(II) reservoir reacting with the ferric primary precipitates. Therefore, DIR progressively gave way to manganese reduction and organic carbon oxidation (DMR), which reduced MnOOH to form Mn(II)-rich carbonates in the form of kutnahorite and Mn-calcite. Co-bearing Fe(OH)₃ would have precipitated and was ultimately preserved as Co-bearing hematite during diagenesis. (3) Deposition of manganese-rich sediment occurred at even shallower oceanic depths (maximum regression) where aerobic organic carbon oxidation replaced DMR, resulting in Ca-rich carbonates such as Mn-bearing calcite and Ca-kutnahorite, yet with a low carbon isotope signature recording aerobic conditions of organic carbon cycling. Mn(III) reduction at this stage was curtailed, leading to massive precipitation of MnOOH which was diagenetically transformed into braunite and friedelite. Simultaneous precipitation of Co-bearing Fe(OH)₃ would have continued but at much more subdued rates. Repeated transgressive-regressive cycles resulted in the cyclic BIF-hematite lutite- manganese ore nature of the Hotazel Formation in an oxidized oceanic environment at the onset of the Great Oxidation Event, which was nonetheless never oxic enough to drive Mn(II) oxidation fully to its tetravalent state. The mineralogy and species-specific geochemistry of the Hotazel strata, and more specifically the carbonate fraction thereof, appear to faithfully capture the chemistry of the primary depositional environment in a progressively evolving Earth System. This project opens the door for more studies focusing on better constraining primary versus diagenetic depositional 2020 Hotazel Fe and Mn deposition mechanisms of iron and manganese during the period leading up to the GOE, and possibly re-defining the significance of Fe and Mn as invaluable redox proxies in a rapidly changing planet.
- Full Text:
- Date Issued: 2020
A sociological understanding of contemporary child marriage in Mabvuku, Harare, Zimbabwe
- Authors: Madzivire, Shamso Christine
- Date: 2020
- Subjects: Child marriage -- Zimbabwe -- Mabvuku , Child marriage -- Zimbabwe -- Case studies , Shona (African people) -- Social life and customs , Marriage customs and rites -- Zimbabwe , Shona (African people) -- Marriage customs and rites , Marriage -- Zimbabwe
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142566 , vital:38091
- Description: Child marriage is a phenomenon that has been increasingly recognised as a global problem since the late nineteenth century. Since then, scholars across many disciplines along with various agencies such as government bodies and non-governmental organisations have tirelessly engaged in research exploring the causes and consequences of this practice and in developing prevention and mitigation strategies. These research efforts have been concentrated in some parts of the world and not others, with the findings in many cases being generalised problematically across different geographical areas. This thesis stands as a response to the dearth of academic research on child marriage in present-day Zimbabwe and simultaneously highlights the significance of studying the specificities of child marriage under particular historical and spatial conditions. The main objective of this thesis is to explore and understand child marriage as a part of modernday marriage practices in Zimbabwe, through a case study of child marriage in Mabvuku in Harare. In addressing this objective, it is hoped that new ways of thinking around this phenomenon will become evident. In addressing this main objective, the thesis considers the experiences of child brides, the drivers and consequences of child and post-child marriage experiences. It does this seeking to understand child marriage with reference to the types of marital unions which exist amongst Shona people in pre-colonial times and in post-colonial Zimbabwe. The thesis adopts a qualitative research methodology which involved in-depth semistructured interviews with 25 women in Mabvuku who were married before the age of 18, along with focus group discussions with community workers and interviews with pertinent government and non-government representatives. Due to certain challenges with current theorising about child marriage, there is an attempt to build theory by drawing upon in particular the Zimbabwean notion and practice of hunhu. A key conclusion is that child marriage in present-day Zimbabwe is in part a result of family transitions which arose during the time of colonialism and continue to this day.
- Full Text:
- Date Issued: 2020
- Authors: Madzivire, Shamso Christine
- Date: 2020
- Subjects: Child marriage -- Zimbabwe -- Mabvuku , Child marriage -- Zimbabwe -- Case studies , Shona (African people) -- Social life and customs , Marriage customs and rites -- Zimbabwe , Shona (African people) -- Marriage customs and rites , Marriage -- Zimbabwe
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142566 , vital:38091
- Description: Child marriage is a phenomenon that has been increasingly recognised as a global problem since the late nineteenth century. Since then, scholars across many disciplines along with various agencies such as government bodies and non-governmental organisations have tirelessly engaged in research exploring the causes and consequences of this practice and in developing prevention and mitigation strategies. These research efforts have been concentrated in some parts of the world and not others, with the findings in many cases being generalised problematically across different geographical areas. This thesis stands as a response to the dearth of academic research on child marriage in present-day Zimbabwe and simultaneously highlights the significance of studying the specificities of child marriage under particular historical and spatial conditions. The main objective of this thesis is to explore and understand child marriage as a part of modernday marriage practices in Zimbabwe, through a case study of child marriage in Mabvuku in Harare. In addressing this objective, it is hoped that new ways of thinking around this phenomenon will become evident. In addressing this main objective, the thesis considers the experiences of child brides, the drivers and consequences of child and post-child marriage experiences. It does this seeking to understand child marriage with reference to the types of marital unions which exist amongst Shona people in pre-colonial times and in post-colonial Zimbabwe. The thesis adopts a qualitative research methodology which involved in-depth semistructured interviews with 25 women in Mabvuku who were married before the age of 18, along with focus group discussions with community workers and interviews with pertinent government and non-government representatives. Due to certain challenges with current theorising about child marriage, there is an attempt to build theory by drawing upon in particular the Zimbabwean notion and practice of hunhu. A key conclusion is that child marriage in present-day Zimbabwe is in part a result of family transitions which arose during the time of colonialism and continue to this day.
- Full Text:
- Date Issued: 2020