Identifying growth criteria and sediment movement mechanisms of needle ice using high-frequency environmental and visual monitoring
- Authors: Borg, Carl-Johan
- Date: 2017
- Subjects: Frazil ice , Sediment transport , Ice mechanics , Photography -- Digital techniques , Environmental monitoring
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/17656 , vital:22268
- Description: Environmental growth conditions and mechanisms involved in sediment transport by needle ice have historically been difficult to assess and are poorly documented. The spatial and temporal dynamics that relate to the environment, growth and decay of needle ice are not fully understood. This study monitored needle ice growth, melt and visually identified sediment displacement mechanisms by needle ice, with the aim of revealing environmental growth criteria, timing of growth/melt, ground-surface-air energy balance and sediment displacement mechanisms. Furthermore, the impact of needle ice displacement on vegetation and patterned ground formation was analysed. High-frequency visual monitoring, using three cameras, supplemented by high-frequency measurements of air temperature, soil moisture and wind speed was used to investigate needle ice growth and decay dynamics. Results from visual and environmental monitoring of needle ice growth, showed that the needle ice growing environment was more dynamic, especially in terms of surface temperature, than previously argued. Needle ice growth was observed to occur during surface temperatures from -2.0°C to 2.2°C, soil moisture levels from 0.4% to 37.4% and in winds speeds of 0 m/s to 12.6 m/s. Needle ice initiation was documented a few minutes to hours before or after the onset of surface temperature dropping to below 0°C. Imagery displayed that the depth of ice nucleation was variable within the soil column, possibly relating to the energy balance of radiative cooling, convective heat loss, ground conductivity and latent heat release at the air-surface-ground boundary. Heaving and resettling, toppling and rolling were identified as slope displacement mechanisms when needle ice decayed. Animal trampling and hail were additionally documented as substantial surface altering processes. Furthermore, no impact of needle ice reducing vegetation stability was identified, although a tendency to hinder vegetation expansion was noted. Also, no creation of patterned ground was observed as a result of needle ice decay.
- Full Text:
- Date Issued: 2017
- Authors: Borg, Carl-Johan
- Date: 2017
- Subjects: Frazil ice , Sediment transport , Ice mechanics , Photography -- Digital techniques , Environmental monitoring
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/17656 , vital:22268
- Description: Environmental growth conditions and mechanisms involved in sediment transport by needle ice have historically been difficult to assess and are poorly documented. The spatial and temporal dynamics that relate to the environment, growth and decay of needle ice are not fully understood. This study monitored needle ice growth, melt and visually identified sediment displacement mechanisms by needle ice, with the aim of revealing environmental growth criteria, timing of growth/melt, ground-surface-air energy balance and sediment displacement mechanisms. Furthermore, the impact of needle ice displacement on vegetation and patterned ground formation was analysed. High-frequency visual monitoring, using three cameras, supplemented by high-frequency measurements of air temperature, soil moisture and wind speed was used to investigate needle ice growth and decay dynamics. Results from visual and environmental monitoring of needle ice growth, showed that the needle ice growing environment was more dynamic, especially in terms of surface temperature, than previously argued. Needle ice growth was observed to occur during surface temperatures from -2.0°C to 2.2°C, soil moisture levels from 0.4% to 37.4% and in winds speeds of 0 m/s to 12.6 m/s. Needle ice initiation was documented a few minutes to hours before or after the onset of surface temperature dropping to below 0°C. Imagery displayed that the depth of ice nucleation was variable within the soil column, possibly relating to the energy balance of radiative cooling, convective heat loss, ground conductivity and latent heat release at the air-surface-ground boundary. Heaving and resettling, toppling and rolling were identified as slope displacement mechanisms when needle ice decayed. Animal trampling and hail were additionally documented as substantial surface altering processes. Furthermore, no impact of needle ice reducing vegetation stability was identified, although a tendency to hinder vegetation expansion was noted. Also, no creation of patterned ground was observed as a result of needle ice decay.
- Full Text:
- Date Issued: 2017
'n Sintaktiese ondersoek na die gebruik van onderskikkende voegwoorde en sinsverbindende woorde in Afrikaans
- Authors: Bosch, Agnes Barbara
- Date: 1984
- Subjects: Afrikaans language -- Conjunctions , Afrikaans language -- Syntax
- Language: Afrikaans
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3613 , http://hdl.handle.net/10962/d1005906 , Afrikaans language -- Conjunctions , Afrikaans language -- Syntax
- Full Text:
- Date Issued: 1984
- Authors: Bosch, Agnes Barbara
- Date: 1984
- Subjects: Afrikaans language -- Conjunctions , Afrikaans language -- Syntax
- Language: Afrikaans
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3613 , http://hdl.handle.net/10962/d1005906 , Afrikaans language -- Conjunctions , Afrikaans language -- Syntax
- Full Text:
- Date Issued: 1984
Teaching pharmacology: issues of language and learning in a multilingual classroom setting
- Boschmans, Shirley-Anne Inez
- Authors: Boschmans, Shirley-Anne Inez
- Date: 2012
- Subjects: English language -- Study and teaching -- South Africa , Pharmacology -- Terminology , Multicultural education , Second language acquisition
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9562 , http://hdl.handle.net/10948/d1013398
- Description: The medium for teaching and learning in South African universities is not the mother tongue of the majority of students and this has been reported to be a barrier to achievement (Department of Education, 2002). Poor English language skills, as well as poor discipline specific vocabulary knowledge, can lead to poor study techniques with the students resorting to rote learning as they are unable to interpret the recommended texts (Gow, Kember, & Chow, 1991; Shembe, 2002). In 2005 at the NMMU a significant difference was reported between the marks achieved for the Pharmacology 2 (ZCL2) module by English first language (EFL) students and the English second language students (EAL) (Boschmans & McCartney, 2005). These finding provided motivation for this study which interrogates issues of language and learning in a multilingual Pharmacology classroom. A mixed methods approach, which employed a concurrent triangulation design with quantitative dominance, was used. Two parallel studies were undertaken. One consisted of a quasi-experimental, pre-test and post-test control group design using an intervention which consisted of the application of the didactical practice of exploratory talk with an experimental sample group during ZCL2 Supplementary Instruction sessions (SI). A second study involved a parallel data collection from the ZCL303 and ZCL401 Pharmacy students at the NMMU to investigate possible effects of academic progression. Purposive, homogenous sampling was used in selection of the samples. The mean ZCL2 mark for the experimental group (58.70±14.14 percent) of students who experienced the intervention (application of exploratory talk) was significantly higher (p = .0004) than the mark achieved by the ZCL2 comparison group (46.47±14.48). This Abstract difference was of high practical significance (Cohen‟s d = 0.85). This quantitative finding was supported by the qualitative data where the students expressed support for the discussion sessions (application of exploratory talk) held during SI sessions. There was a significant increase, with academic progression, of English reading comprehension amongst the EFL students (p = .025) but not in the EAL students and BPharm1 weighted average (p < .001) as well as SI attendance (p = .02) correlated significantly with achievement in ZCL2. The findings of this study provide insights into the teaching of Pharmacology in a multilingual classroom. The qualitative results in addition to strengthening the quantitative findings through triangulation have provided a rich, deep and detailed description of the lived experiences of Pharmacology students. The data will provide insights into students‟ experiences for Pharmacy academics and are a resource for understanding student perspectives.
- Full Text:
- Date Issued: 2012
- Authors: Boschmans, Shirley-Anne Inez
- Date: 2012
- Subjects: English language -- Study and teaching -- South Africa , Pharmacology -- Terminology , Multicultural education , Second language acquisition
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9562 , http://hdl.handle.net/10948/d1013398
- Description: The medium for teaching and learning in South African universities is not the mother tongue of the majority of students and this has been reported to be a barrier to achievement (Department of Education, 2002). Poor English language skills, as well as poor discipline specific vocabulary knowledge, can lead to poor study techniques with the students resorting to rote learning as they are unable to interpret the recommended texts (Gow, Kember, & Chow, 1991; Shembe, 2002). In 2005 at the NMMU a significant difference was reported between the marks achieved for the Pharmacology 2 (ZCL2) module by English first language (EFL) students and the English second language students (EAL) (Boschmans & McCartney, 2005). These finding provided motivation for this study which interrogates issues of language and learning in a multilingual Pharmacology classroom. A mixed methods approach, which employed a concurrent triangulation design with quantitative dominance, was used. Two parallel studies were undertaken. One consisted of a quasi-experimental, pre-test and post-test control group design using an intervention which consisted of the application of the didactical practice of exploratory talk with an experimental sample group during ZCL2 Supplementary Instruction sessions (SI). A second study involved a parallel data collection from the ZCL303 and ZCL401 Pharmacy students at the NMMU to investigate possible effects of academic progression. Purposive, homogenous sampling was used in selection of the samples. The mean ZCL2 mark for the experimental group (58.70±14.14 percent) of students who experienced the intervention (application of exploratory talk) was significantly higher (p = .0004) than the mark achieved by the ZCL2 comparison group (46.47±14.48). This Abstract difference was of high practical significance (Cohen‟s d = 0.85). This quantitative finding was supported by the qualitative data where the students expressed support for the discussion sessions (application of exploratory talk) held during SI sessions. There was a significant increase, with academic progression, of English reading comprehension amongst the EFL students (p = .025) but not in the EAL students and BPharm1 weighted average (p < .001) as well as SI attendance (p = .02) correlated significantly with achievement in ZCL2. The findings of this study provide insights into the teaching of Pharmacology in a multilingual classroom. The qualitative results in addition to strengthening the quantitative findings through triangulation have provided a rich, deep and detailed description of the lived experiences of Pharmacology students. The data will provide insights into students‟ experiences for Pharmacy academics and are a resource for understanding student perspectives.
- Full Text:
- Date Issued: 2012
The biotransformation of phenolic pollutants using polyphenol oxidase
- Authors: Boshoff, Aileen
- Date: 2002
- Subjects: Polyphenol oxidase Sewage -- Purification
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3976 , http://hdl.handle.net/10962/d1004035
- Description: The potential of using mushroom polyphenol oxidase (EC 1.14.18.1) as a biocatalyst for the biotransformation of phenols to produce catechols in an aqueous medium was investigated. Polyphenol oxidase is characterised by two distinct reactions i.e., the ortho-hydroxylation of phenols to catechols (cresolase activity) and the subsequent oxidation of catechols to orthoquinones (catecholase activity). In order to facilitate the development of a process to produce catechols, the accumulation of catechol as a true intermediate product released in the reaction system needed to be investigated, as its release had been disputed due to the oxidation of catechols to o-quinones. Using LC-MS, catechol products were successfully identified as true intermediate products formed during biocatalytic reactions in water.
- Full Text:
- Date Issued: 2002
- Authors: Boshoff, Aileen
- Date: 2002
- Subjects: Polyphenol oxidase Sewage -- Purification
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3976 , http://hdl.handle.net/10962/d1004035
- Description: The potential of using mushroom polyphenol oxidase (EC 1.14.18.1) as a biocatalyst for the biotransformation of phenols to produce catechols in an aqueous medium was investigated. Polyphenol oxidase is characterised by two distinct reactions i.e., the ortho-hydroxylation of phenols to catechols (cresolase activity) and the subsequent oxidation of catechols to orthoquinones (catecholase activity). In order to facilitate the development of a process to produce catechols, the accumulation of catechol as a true intermediate product released in the reaction system needed to be investigated, as its release had been disputed due to the oxidation of catechols to o-quinones. Using LC-MS, catechol products were successfully identified as true intermediate products formed during biocatalytic reactions in water.
- Full Text:
- Date Issued: 2002
Development of integrated biological processing for the biodesalination of sulphate- and metal-rich wastewaters
- Authors: Boshoff, Genevieve Ann
- Date: 1999
- Subjects: Sewage -- Purification -- Biological treatment Sulfates Mineral industries -- Environmental aspects
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3899 , http://hdl.handle.net/10962/d1003958
- Description: The substantial pollution threat to the South African environment from acid mine drainage (AMD) effluents has been well documented. Due to the juvenile nature of acidity in these flows, any remediation strategies implemented will need to function effectively and at low cost for long periods of time. The widespread use of sulphate reducing biological systems for the treatment of such effluents, and in particular large volume flows, has been limited. The supply of inexpensive electron donor and carbon sources, as well as appropriate reactor designs capable of handling large volume flows, have been identified as among the principal factors limiting development of this technology. The broad aim of the research programme reported here was to undertake an evaluation of the feasibility of an algal-bacterial integrated ponding system for the treatment of AMD, and the waste stabilisation pond (WSP) as an appropriate reactor design for this application. The study attempted to demonstrate the feasibility of individual unit operations in a proposed process train using complex organic carbon serving as the electron donor source for the sulphate reducing bacteria (SRB). Studies were undertaken as laboratory and pilot-scale investigations. Tannery effluent was shown to be a functional carbon source for biological sulphate reduction, with effective removal of sulphate and organics being recorded. In turn, the use of biological sulphate reduction for the treatment of tannery effluent was demonstrated. Algal biomass was shown in laboratory studies to function as an effective carbon source for biological sulphate reduction. It is known that micro-algae produce large quantities of photosynthate which is released to the growth medium under conditions of physiological stress. The potential for the use of photosynthate production in high rate algal ponding systems and its manipulation and use as a sustainable carbon source for sulphate reduction was investigated. Growth of a mixed culture of Dunaliella under conditions of light, temperature and salinity stress demonstrated production of large quantities of organic carbon. However, growth was inhibited at high temperatures. An elevation of salinity levels led to a decrease in growth of Dunaliella, but to increased organic carbon production. Spirulina spp., on the other hand, grew well at higher temperatures but showed the highest organic carbon production, and release to the medium, under low light conditions. These results led to a proposed process for the integration of algal ponding into an integrated system for the treatment of AMD. The algal biomass may be fed into the anaerobic digester as a carbon source, or it may be passed into a High Rate Algal Pond (HRAP) where it is stressed to enhance the organic carbon content. This can then be fed into the anaerobic digester as a carbon source. The impact of high levels of sulphide in the water feeding to the algal growth compartment was investigated. Spirulina spp. isolated from a tannery waste stabilisation pond was shown to be a sulphidophilic strain of cyanobacterium, capable of being adapted to high concentrations of sulphide. Dunaliella salina on the other hand was less tolerant. These results demonstrated the practical use of algal biomass providing an oxygen-rich cap for odour control on the surface of the facultative pond as well for the secondary treatment of sulphide-rich overflow to the High Rate Algal Pond. The ability of micro-algae to elevate the pH of their surrounding environment was evaluated as a functional precipitant and neutralisation reagent for acidic metal containing wastewater. Spirulina spp. was shown to perform effectively. D. salina was less functional in this environment. Anacystis spp. was effective in elevating the pH of a defined medium as well as a zinc-rich effluent. These results indicated the practicality of a neutralising function for algal ponds in the treatment of AMD. Metal removal in the system was found to be a combined function of sulphide precipitation, removal by binding to micro-algal biomass and extracellular polymeric substances. The feasibility of waste stabilisation ponding technology use for the treatment of large volume AMD effluents was provisionally demonstrated. It was shown that complex carbon sources would be used as efficient electron donors for sulphate reduction. The integration of algal ponding into the system provides for the generation of a sustainable carbon source, odour control with the recycling of oxygen-rich water onto the top of the facultative pond, secondary treatment of the anaerobic digester overflow, and the neutralisation of the incoming acidic effluents and removal of heavy metals. Integration of the individual unit operations, the feasibility of which has been provisionally demonstrated in this study, into a continuous process train is being investigated in follow-upstudies.
- Full Text:
- Date Issued: 1999
- Authors: Boshoff, Genevieve Ann
- Date: 1999
- Subjects: Sewage -- Purification -- Biological treatment Sulfates Mineral industries -- Environmental aspects
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3899 , http://hdl.handle.net/10962/d1003958
- Description: The substantial pollution threat to the South African environment from acid mine drainage (AMD) effluents has been well documented. Due to the juvenile nature of acidity in these flows, any remediation strategies implemented will need to function effectively and at low cost for long periods of time. The widespread use of sulphate reducing biological systems for the treatment of such effluents, and in particular large volume flows, has been limited. The supply of inexpensive electron donor and carbon sources, as well as appropriate reactor designs capable of handling large volume flows, have been identified as among the principal factors limiting development of this technology. The broad aim of the research programme reported here was to undertake an evaluation of the feasibility of an algal-bacterial integrated ponding system for the treatment of AMD, and the waste stabilisation pond (WSP) as an appropriate reactor design for this application. The study attempted to demonstrate the feasibility of individual unit operations in a proposed process train using complex organic carbon serving as the electron donor source for the sulphate reducing bacteria (SRB). Studies were undertaken as laboratory and pilot-scale investigations. Tannery effluent was shown to be a functional carbon source for biological sulphate reduction, with effective removal of sulphate and organics being recorded. In turn, the use of biological sulphate reduction for the treatment of tannery effluent was demonstrated. Algal biomass was shown in laboratory studies to function as an effective carbon source for biological sulphate reduction. It is known that micro-algae produce large quantities of photosynthate which is released to the growth medium under conditions of physiological stress. The potential for the use of photosynthate production in high rate algal ponding systems and its manipulation and use as a sustainable carbon source for sulphate reduction was investigated. Growth of a mixed culture of Dunaliella under conditions of light, temperature and salinity stress demonstrated production of large quantities of organic carbon. However, growth was inhibited at high temperatures. An elevation of salinity levels led to a decrease in growth of Dunaliella, but to increased organic carbon production. Spirulina spp., on the other hand, grew well at higher temperatures but showed the highest organic carbon production, and release to the medium, under low light conditions. These results led to a proposed process for the integration of algal ponding into an integrated system for the treatment of AMD. The algal biomass may be fed into the anaerobic digester as a carbon source, or it may be passed into a High Rate Algal Pond (HRAP) where it is stressed to enhance the organic carbon content. This can then be fed into the anaerobic digester as a carbon source. The impact of high levels of sulphide in the water feeding to the algal growth compartment was investigated. Spirulina spp. isolated from a tannery waste stabilisation pond was shown to be a sulphidophilic strain of cyanobacterium, capable of being adapted to high concentrations of sulphide. Dunaliella salina on the other hand was less tolerant. These results demonstrated the practical use of algal biomass providing an oxygen-rich cap for odour control on the surface of the facultative pond as well for the secondary treatment of sulphide-rich overflow to the High Rate Algal Pond. The ability of micro-algae to elevate the pH of their surrounding environment was evaluated as a functional precipitant and neutralisation reagent for acidic metal containing wastewater. Spirulina spp. was shown to perform effectively. D. salina was less functional in this environment. Anacystis spp. was effective in elevating the pH of a defined medium as well as a zinc-rich effluent. These results indicated the practicality of a neutralising function for algal ponds in the treatment of AMD. Metal removal in the system was found to be a combined function of sulphide precipitation, removal by binding to micro-algal biomass and extracellular polymeric substances. The feasibility of waste stabilisation ponding technology use for the treatment of large volume AMD effluents was provisionally demonstrated. It was shown that complex carbon sources would be used as efficient electron donors for sulphate reduction. The integration of algal ponding into the system provides for the generation of a sustainable carbon source, odour control with the recycling of oxygen-rich water onto the top of the facultative pond, secondary treatment of the anaerobic digester overflow, and the neutralisation of the incoming acidic effluents and removal of heavy metals. Integration of the individual unit operations, the feasibility of which has been provisionally demonstrated in this study, into a continuous process train is being investigated in follow-upstudies.
- Full Text:
- Date Issued: 1999
Crime and punishment Mzansi style: an exploration of the discursive production of criminality and popular justice in South Africa’s Daily Sun
- Authors: Boshoff, Priscilla
- Date: 2017
- Subjects: Daily Sun (South Africa) , Tabloid newpapers -- South Africa , Crime in mass media , Justice in mass media , Police in mass media , Newpapers -- South Africa , Newpapers -- Objectivity -- South Africa , Women -- Violence against -- South Africa -- Press coverage , Witchcraft -- South Africa -- Press coverage , Police -- South Africa -- Press coverage
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/44419 , vital:25406
- Description: The highly popular South African tabloid the Daily Sun, established post-apartheid in 2002, is known for its sensationalist and controversial reporting of black township life. Read by over five million black working class readers, much of its reporting concerns the crimes experienced by them and their struggles for justice. The extraordinarily high rate of violent crime in township areas for which South Africa became infamous during the 1980s did not decrease as much as hoped after the political transition in 1994 and crime overshadowed the first decades of the new administration, adding to the frustrations generated by the slow pace of social and economic reform. Part of the Daily Sun’s success can be attributed to how, around these linked concerns, it fashions for its readers a particular discursive world, Sunland. It is the phatic relationship that the tabloid maintains between itself and its readers which forms the foundation upon which this textual study rests. In approaching the tabloid’s representations of crime I draw on cultural criminological understandings of crime as culture and the formative relationship in this regard between crime and the media. As a preeminent site of cultural production in contemporary society, the media contribute to the ongoing definition of what constitutes crime, who is criminal and what counts as justice. This constructivist approach is congruent with Foucault’s notions of discourse and the subject, and I argue that the various competing discourses about crime and justice which appear in the paper establish a set of subjectivities with which its readers may identity. The thesis explores the rhetorical and discursive means by which such subject positions are constructed within the ‘grid of intelligibility’ created by the Daily Sun’s reportage, and using the spatial metaphor of the ‘map’ I trace the contours of the Daily Sun’s domain with regard to crime and popular justice. To this end, the approach taken is a qualitative one which draws eclectically on a variety of interpretive methods, including semiotic, narrative and discourse analysis. Using these, I map the relations between People’s Justice, the police, gender relations and witchcraft crimes, four areas chosen from a broad thematic content analysis of the complete set of editions from 2011. I show how these are not discreet but co-constructed areas within the coverage, drawing their meaning mutually from a range of conflictual relationships derived from the conditions of post-apartheid social life.
- Full Text:
- Date Issued: 2017
- Authors: Boshoff, Priscilla
- Date: 2017
- Subjects: Daily Sun (South Africa) , Tabloid newpapers -- South Africa , Crime in mass media , Justice in mass media , Police in mass media , Newpapers -- South Africa , Newpapers -- Objectivity -- South Africa , Women -- Violence against -- South Africa -- Press coverage , Witchcraft -- South Africa -- Press coverage , Police -- South Africa -- Press coverage
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/44419 , vital:25406
- Description: The highly popular South African tabloid the Daily Sun, established post-apartheid in 2002, is known for its sensationalist and controversial reporting of black township life. Read by over five million black working class readers, much of its reporting concerns the crimes experienced by them and their struggles for justice. The extraordinarily high rate of violent crime in township areas for which South Africa became infamous during the 1980s did not decrease as much as hoped after the political transition in 1994 and crime overshadowed the first decades of the new administration, adding to the frustrations generated by the slow pace of social and economic reform. Part of the Daily Sun’s success can be attributed to how, around these linked concerns, it fashions for its readers a particular discursive world, Sunland. It is the phatic relationship that the tabloid maintains between itself and its readers which forms the foundation upon which this textual study rests. In approaching the tabloid’s representations of crime I draw on cultural criminological understandings of crime as culture and the formative relationship in this regard between crime and the media. As a preeminent site of cultural production in contemporary society, the media contribute to the ongoing definition of what constitutes crime, who is criminal and what counts as justice. This constructivist approach is congruent with Foucault’s notions of discourse and the subject, and I argue that the various competing discourses about crime and justice which appear in the paper establish a set of subjectivities with which its readers may identity. The thesis explores the rhetorical and discursive means by which such subject positions are constructed within the ‘grid of intelligibility’ created by the Daily Sun’s reportage, and using the spatial metaphor of the ‘map’ I trace the contours of the Daily Sun’s domain with regard to crime and popular justice. To this end, the approach taken is a qualitative one which draws eclectically on a variety of interpretive methods, including semiotic, narrative and discourse analysis. Using these, I map the relations between People’s Justice, the police, gender relations and witchcraft crimes, four areas chosen from a broad thematic content analysis of the complete set of editions from 2011. I show how these are not discreet but co-constructed areas within the coverage, drawing their meaning mutually from a range of conflictual relationships derived from the conditions of post-apartheid social life.
- Full Text:
- Date Issued: 2017
Alternative mythical structures in the fiction of Patrick White
- Authors: Bosman, Brenda Evadne
- Date: 1990
- Subjects: White, Patrick, 1912-1990 , White, Patrick, 1912-1990 -- Criticism and interpretation , Myth in literature
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2170 , http://hdl.handle.net/10962/d1001821
- Description: The texts in this study interrogate the dominant myths which have affected the constructs of identity and history in the white Australian socio-historical context. These myths are exposed by White as ideologically determined and as operating by processes of exclusion, repression and marginalisation. White challenges the autonomy of both European and Australian cultures, reveals the ideological complicity between them and adopts a critical approach to all Western cultural assumptions. As a post-colonial writer, White shares the need of both post-colonising and post-colonised groups for an identity established not in terms of the colonial power but in terms of themselves. As a dissident white male, he is a privileged member of the post- colonising group but one who rejects the dominant discourses as illegitimate and unlegitimating. He offers a re-writing of the myths underpinning colonial and post-colonising discourses which privileges their suppressed and repressed elements. His re-writings affect aboriginal men and women, white women and the 'privileged' white male whose subjection to social control is masked as unproblematic freedom. White's re-writing of myth enbraces the post-modern as well as the post- colonial. He not only deconstructs and demystifies the phallogocentric/ethnocentric order of things; he also attempts to avoid totalization by privileging indeterminacy, fragmentation, hybridization and those liminary states which defy articulation: the ecstatic, the abject, the unspeakable. He himself is denied authority in that his re-writings are presented as mere acts in the always provisional process of making interpretations. White acknowledges the problematics of both presentation and re-presentation - an unresolved tension between the post-colonial desire for self-definition and the post-modern decentring of all meaning and interpretation permeates his discourse. The close readings of the texts attempt, accordingly, to reflect varying oppositional strategies: those which seek to overturn hierarchies and expose power-relations and those which seek an idiom in which contemporary Australia may find its least distorted reflexion. Within this ideological context, the Lacanian thematics of the subject, and their re-writing by Kristeva, are linked with dialectical criticism in an attempt to reflect a strictly provisional process of (re) construction
- Full Text:
- Date Issued: 1990
- Authors: Bosman, Brenda Evadne
- Date: 1990
- Subjects: White, Patrick, 1912-1990 , White, Patrick, 1912-1990 -- Criticism and interpretation , Myth in literature
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2170 , http://hdl.handle.net/10962/d1001821
- Description: The texts in this study interrogate the dominant myths which have affected the constructs of identity and history in the white Australian socio-historical context. These myths are exposed by White as ideologically determined and as operating by processes of exclusion, repression and marginalisation. White challenges the autonomy of both European and Australian cultures, reveals the ideological complicity between them and adopts a critical approach to all Western cultural assumptions. As a post-colonial writer, White shares the need of both post-colonising and post-colonised groups for an identity established not in terms of the colonial power but in terms of themselves. As a dissident white male, he is a privileged member of the post- colonising group but one who rejects the dominant discourses as illegitimate and unlegitimating. He offers a re-writing of the myths underpinning colonial and post-colonising discourses which privileges their suppressed and repressed elements. His re-writings affect aboriginal men and women, white women and the 'privileged' white male whose subjection to social control is masked as unproblematic freedom. White's re-writing of myth enbraces the post-modern as well as the post- colonial. He not only deconstructs and demystifies the phallogocentric/ethnocentric order of things; he also attempts to avoid totalization by privileging indeterminacy, fragmentation, hybridization and those liminary states which defy articulation: the ecstatic, the abject, the unspeakable. He himself is denied authority in that his re-writings are presented as mere acts in the always provisional process of making interpretations. White acknowledges the problematics of both presentation and re-presentation - an unresolved tension between the post-colonial desire for self-definition and the post-modern decentring of all meaning and interpretation permeates his discourse. The close readings of the texts attempt, accordingly, to reflect varying oppositional strategies: those which seek to overturn hierarchies and expose power-relations and those which seek an idiom in which contemporary Australia may find its least distorted reflexion. Within this ideological context, the Lacanian thematics of the subject, and their re-writing by Kristeva, are linked with dialectical criticism in an attempt to reflect a strictly provisional process of (re) construction
- Full Text:
- Date Issued: 1990
Op hom die groot hosannas : enkele aspekte van die modern Christelike poësie in Afrikaans
- Authors: Bosman, Maria Elizabeth
- Date: 1989
- Subjects: Afrikaans poetry -- History and criticism , Religious poetry, Afrikaans -- History and criticism , Christian poetry, Afrikaans , Calvinism in literature , Blum, Peter, 1925-1990 , Rousseau, Ina , Cussons, Sheila , De Villiers, I. L., 1936-2009 , Cloete, T. T. (Theunis Theodorus), 1924-2015 , Spies, Lina , Müller, Petra, 1935-
- Language: Afrikaans
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3566 , http://hdl.handle.net/10962/d1002089 , Afrikaans poetry -- History and criticism , Religious poetry, Afrikaans -- History and criticism
- Description: This study is concerned with modern Christian poetry in Afrikaans. Afrikaans poetry, which initially carried the clear stamp of the Afrikaner's Calvinistic view of life, gradually assumed a new image to the extent that it could no longer be recognised as religious and specifically Calvinistic poetry. To the contrary, modern Afrikaans Christian poetry is the expression of a contemporary conceptualisation of the very same gospel. The occasional violent reaction especially of conservative institutions to so called "unchristian" modern poetry in Afrikaans during the past three decades, has prompted this study which attempts to illustrate that modern Afrikaans poetry still exhibits a strong Christian element. The essential qualities of contemporary Christian poetry in Afrikaans are illustrated in the discussion of the works of particular leading Afrikaans poets. Chapter 3 attempts to indicate a transitional stage between traditional and modern Christian poetry by means of an overview of the latest tendencies and approaches, with brief references to the recent poetry of the Louws, the poetry of Peter Blum as the initial exponent of the poetry of the Sixties, and the poetry of Ina Rousseau. The work of Sheila Cussons, eminent Roman Catholic (and thus also Christian) poet who is probably the most impressive contemporary exponent of metaphysical/mystic poetry in Afrikaans, is discussed in chapter 4. Chapter 5 illustrates the traditional Calvinistic Christian point of view and Christian experience as represented in the poetry of I.L. de Villiers. The poetification of the ministry adds new dimension to religions poetry in Afrikaans. Chapter 6 constitutes a discussion of the works of T.T . Cloete, the most significant contemporary Reformed poet in Afrikaans indicating the extent to which the many related facets embodied in his poetry consistently reflect a Christian attitude and are unified in and encompassed by the principle of Soli Deo Gloria. Chapter 7, by way of conclusion, reviews the religious poetry of Lina Spies and Petra Müller who write accessible popular poetry, nevertheless exploring interesting references. In conjunction with the poetry of Ina Rosseau, this poetry represents a contribution to modern Afrikaans religious poetry from a feminine point of view
- Full Text:
- Date Issued: 1989
- Authors: Bosman, Maria Elizabeth
- Date: 1989
- Subjects: Afrikaans poetry -- History and criticism , Religious poetry, Afrikaans -- History and criticism , Christian poetry, Afrikaans , Calvinism in literature , Blum, Peter, 1925-1990 , Rousseau, Ina , Cussons, Sheila , De Villiers, I. L., 1936-2009 , Cloete, T. T. (Theunis Theodorus), 1924-2015 , Spies, Lina , Müller, Petra, 1935-
- Language: Afrikaans
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3566 , http://hdl.handle.net/10962/d1002089 , Afrikaans poetry -- History and criticism , Religious poetry, Afrikaans -- History and criticism
- Description: This study is concerned with modern Christian poetry in Afrikaans. Afrikaans poetry, which initially carried the clear stamp of the Afrikaner's Calvinistic view of life, gradually assumed a new image to the extent that it could no longer be recognised as religious and specifically Calvinistic poetry. To the contrary, modern Afrikaans Christian poetry is the expression of a contemporary conceptualisation of the very same gospel. The occasional violent reaction especially of conservative institutions to so called "unchristian" modern poetry in Afrikaans during the past three decades, has prompted this study which attempts to illustrate that modern Afrikaans poetry still exhibits a strong Christian element. The essential qualities of contemporary Christian poetry in Afrikaans are illustrated in the discussion of the works of particular leading Afrikaans poets. Chapter 3 attempts to indicate a transitional stage between traditional and modern Christian poetry by means of an overview of the latest tendencies and approaches, with brief references to the recent poetry of the Louws, the poetry of Peter Blum as the initial exponent of the poetry of the Sixties, and the poetry of Ina Rousseau. The work of Sheila Cussons, eminent Roman Catholic (and thus also Christian) poet who is probably the most impressive contemporary exponent of metaphysical/mystic poetry in Afrikaans, is discussed in chapter 4. Chapter 5 illustrates the traditional Calvinistic Christian point of view and Christian experience as represented in the poetry of I.L. de Villiers. The poetification of the ministry adds new dimension to religions poetry in Afrikaans. Chapter 6 constitutes a discussion of the works of T.T . Cloete, the most significant contemporary Reformed poet in Afrikaans indicating the extent to which the many related facets embodied in his poetry consistently reflect a Christian attitude and are unified in and encompassed by the principle of Soli Deo Gloria. Chapter 7, by way of conclusion, reviews the religious poetry of Lina Spies and Petra Müller who write accessible popular poetry, nevertheless exploring interesting references. In conjunction with the poetry of Ina Rosseau, this poetry represents a contribution to modern Afrikaans religious poetry from a feminine point of view
- Full Text:
- Date Issued: 1989
Between nationalism and transnationalism: entanglements of history, individual narrative, and memory in diaspora spaces in selected transnational fiction
- Authors: Bosman, Sean James
- Date: 2020
- Subjects: Literature and transnationalism , Gurnah, Abdulrazak, 1948- , Gurnah, Abdulrazak, 1948- -- By the sea , Gurnah, Abdulrazak, 1948- -- Gravel heart , Nguyen, Viet Thanh, 1971- , Nguyen, Viet Thanh, 1971- -- The sympathizer , Nguyen, Viet Thanh, 1971- -- The refugees , Urrea, Luis Alberto , Urrea, Luis Alberto -- The house of broken angels , Urrea, Luis Alberto -- The water museum
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/140932 , vital:37930
- Description: This thesis offers close readings and a comparative analysis of selected works by Abdulrazak Gurnah, Viet Thanh Nguyen, and Luis Alberto Urrea. The selected primary texts used are Gurnah’s By the Sea (2000) and Gravel Heart (2017), Nguyen’s The Sympathizer (2015) and The Refugees (2017), and Urrea’s The Water Museum (2015) and The House of Broken Angels (2018). Analyses are informed by a conceptual framework that draws on critical works by Avtar Brah, J. U. Jacobs, Sarah Nuttall, Homi K. Bhabha, Judith Butler, Stuart Hall, Paul Ricoeur, Viet Thanh Nguyen, and Christopher B. Patterson. These theories are deployed to analyse how the selected works engage with the entanglements of history, individual narratives, and memory in the diaspora spaces they articulate. The thesis argues that the selected works indicate an emerging subgenre within the broader category of transnational literature. This subgenre rejects disempowering interpolations of transnational identities. Instead, it prioritises ethical forms of memory. These acknowledge that transnational subjects share at least partial accountability for the precarity they experience in diaspora spaces. The selected literature limns how this may be accomplished by rejecting the label of victim. In so doing, the selected literature also suggests that the elevation of transnationals to full ethical agency would enable them to exercise power in their diaspora spaces. All three authorial projects studied here also give rise to uncomfortable juxtapositions that suggest a mounting fear that, as nationalisms become more pronounced in the UK and the USA, transnationals may have to re-experience conditions from which they have already fled. The thesis concludes by identifying four additional areas of confluence amongst the selected literature worthy of future study.
- Full Text:
- Date Issued: 2020
- Authors: Bosman, Sean James
- Date: 2020
- Subjects: Literature and transnationalism , Gurnah, Abdulrazak, 1948- , Gurnah, Abdulrazak, 1948- -- By the sea , Gurnah, Abdulrazak, 1948- -- Gravel heart , Nguyen, Viet Thanh, 1971- , Nguyen, Viet Thanh, 1971- -- The sympathizer , Nguyen, Viet Thanh, 1971- -- The refugees , Urrea, Luis Alberto , Urrea, Luis Alberto -- The house of broken angels , Urrea, Luis Alberto -- The water museum
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/140932 , vital:37930
- Description: This thesis offers close readings and a comparative analysis of selected works by Abdulrazak Gurnah, Viet Thanh Nguyen, and Luis Alberto Urrea. The selected primary texts used are Gurnah’s By the Sea (2000) and Gravel Heart (2017), Nguyen’s The Sympathizer (2015) and The Refugees (2017), and Urrea’s The Water Museum (2015) and The House of Broken Angels (2018). Analyses are informed by a conceptual framework that draws on critical works by Avtar Brah, J. U. Jacobs, Sarah Nuttall, Homi K. Bhabha, Judith Butler, Stuart Hall, Paul Ricoeur, Viet Thanh Nguyen, and Christopher B. Patterson. These theories are deployed to analyse how the selected works engage with the entanglements of history, individual narratives, and memory in the diaspora spaces they articulate. The thesis argues that the selected works indicate an emerging subgenre within the broader category of transnational literature. This subgenre rejects disempowering interpolations of transnational identities. Instead, it prioritises ethical forms of memory. These acknowledge that transnational subjects share at least partial accountability for the precarity they experience in diaspora spaces. The selected literature limns how this may be accomplished by rejecting the label of victim. In so doing, the selected literature also suggests that the elevation of transnationals to full ethical agency would enable them to exercise power in their diaspora spaces. All three authorial projects studied here also give rise to uncomfortable juxtapositions that suggest a mounting fear that, as nationalisms become more pronounced in the UK and the USA, transnationals may have to re-experience conditions from which they have already fled. The thesis concludes by identifying four additional areas of confluence amongst the selected literature worthy of future study.
- Full Text:
- Date Issued: 2020
A framework to enhance the mobile user experience in an Mlearning interaction
- Authors: Botha, Adele
- Date: 2011
- Subjects: Educational technology , Information technology , Educational innovations , Teaching -- Aids and devices
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9753 , http://hdl.handle.net/10948/d1008163 , Educational technology , Information technology , Educational innovations , Teaching -- Aids and devices
- Description: The new millennium is witness to a telecommunications world that is vastly different from even the recent past with developments in the mobile sector having dramatically changed the Information and Communication Technology (ICT) landscape. Mobile cellular technology has proliferated faster than any previous technology and is now the most ubiquitous technology in the world. The focus of this thesis is the development of a framework to enhance the Mobile User Experience in an Mlearning interaction. This research is contextualised by the goal-oriented use of mobile cellular technologies in a formal educational environment. As such the study, although residing in the field of Human-Computer Interaction (HCI), acknowledges issues arising in the Education Domain as a specific field of application. The aim of the research was to investigate the components of a framework to enhance the Mobile User Experience in an Mlearning interaction. The development of the framework was facilitated by the exploration of: the Mobile User Experience factors and their impact, on the Mobile User Experience of learners participating in a goal-oriented Mlearning interaction. These critical factors were documented in terms of the Mobile User Experience components, and the relationships of these components to each other as well as the Mobile User Experience of an Mlearning interaction. The research, grounded in a phenomenological research philosophy, applied an inductive reasoning approach, and was operationalised through a single case study methodology. A qualitative research strategy was considered appropriate, as the phenomenon of User Experience is linked to the hedonistic attributes of the interaction. This study was conducted in four phases with focus on three embedded units of analysis. The three units of analysis were identified as: The learner as end user in an Mlearning interaction; The educator as designer of the Mlearning interaction; and The Mlearning interaction. The research revealed that the Mobile User Experience of an Mlearning interaction is affected by the mobile user, mobile use, mobile device, mobile business practices, mobile networks, mobile interaction and mobile context. Within the Mlearning interaction the significant components are the learners as mobile users, the enhance interactions, removal of barriers to the interaction, goal-oriented nature of the interaction and the ducational context. Identifying these components and their associated Mobile User Experience factors and impacts, present the main contribution of this thesis. In conclusion, the limitations of the study are documented and topics for future research are outlined.
- Full Text:
- Date Issued: 2011
- Authors: Botha, Adele
- Date: 2011
- Subjects: Educational technology , Information technology , Educational innovations , Teaching -- Aids and devices
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9753 , http://hdl.handle.net/10948/d1008163 , Educational technology , Information technology , Educational innovations , Teaching -- Aids and devices
- Description: The new millennium is witness to a telecommunications world that is vastly different from even the recent past with developments in the mobile sector having dramatically changed the Information and Communication Technology (ICT) landscape. Mobile cellular technology has proliferated faster than any previous technology and is now the most ubiquitous technology in the world. The focus of this thesis is the development of a framework to enhance the Mobile User Experience in an Mlearning interaction. This research is contextualised by the goal-oriented use of mobile cellular technologies in a formal educational environment. As such the study, although residing in the field of Human-Computer Interaction (HCI), acknowledges issues arising in the Education Domain as a specific field of application. The aim of the research was to investigate the components of a framework to enhance the Mobile User Experience in an Mlearning interaction. The development of the framework was facilitated by the exploration of: the Mobile User Experience factors and their impact, on the Mobile User Experience of learners participating in a goal-oriented Mlearning interaction. These critical factors were documented in terms of the Mobile User Experience components, and the relationships of these components to each other as well as the Mobile User Experience of an Mlearning interaction. The research, grounded in a phenomenological research philosophy, applied an inductive reasoning approach, and was operationalised through a single case study methodology. A qualitative research strategy was considered appropriate, as the phenomenon of User Experience is linked to the hedonistic attributes of the interaction. This study was conducted in four phases with focus on three embedded units of analysis. The three units of analysis were identified as: The learner as end user in an Mlearning interaction; The educator as designer of the Mlearning interaction; and The Mlearning interaction. The research revealed that the Mobile User Experience of an Mlearning interaction is affected by the mobile user, mobile use, mobile device, mobile business practices, mobile networks, mobile interaction and mobile context. Within the Mlearning interaction the significant components are the learners as mobile users, the enhance interactions, removal of barriers to the interaction, goal-oriented nature of the interaction and the ducational context. Identifying these components and their associated Mobile User Experience factors and impacts, present the main contribution of this thesis. In conclusion, the limitations of the study are documented and topics for future research are outlined.
- Full Text:
- Date Issued: 2011
An intervention for enhancing the mathematics teaching practices of grade four teachers in the Nelson Mandela Metropolitan area
- Authors: Botha, Adele
- Date: 2011
- Subjects: Mathematics -- Study and teaching , Mathematics , Mathematics -- Handbooks, manuals, etc , Mathematics teachers
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9499 , http://hdl.handle.net/10948/d1008176 , Mathematics -- Study and teaching , Mathematics , Mathematics -- Handbooks, manuals, etc , Mathematics teachers
- Description: Mathematics is regarded as a driving force in economies worldwide. The performance of South African learners in mathematics over the past decade has highlighted that problems are being experienced across all grades. This situation needs to be addressed with urgency. The South African Department of Education stated that quality learning must be the objective for all grades. The implementation of good teaching practices plays a crucial role in improving the quality of education and in guiding learners towards quality learning. To achieve quality mathematics teaching and learning it is imperative to determine what good mathematics teaching practices are. The identification of good mathematic teaching practices will provide a yard stick to measure the mathematics teaching competency of teachers. This study identifies a set of good mathematics teaching practice indicators and evidences applicable to teachers in the Intermediate phase as a first contribution. These indicators and evidences frame the second research contribution: an assessment instrument entitled “A Classroom Observation Tool for Observing Mathematics Teaching Practices in Primary Schools”. As a third research contribution a generic profile of a Grade four mathematics teacher has been built. This generic profile has been built through an analysis of data gathered by means of self-assessment questionnaires completed by the research sample, as well as through applying the observation tool. The value of the generic profile lies in the identification of shared strengths and shared improvement opportunities in the mathematics teaching practice of the sample and as such, it forms the basis of a theory on Grade four mathematics teaching practice. The fourth research contribution is the design and application of an intervention that addresses the shared improvement opportunities. The research study concludes by comparing pre-intervention classroom observation data with post-intervention classroom observation data and reporting on the impact of the intervention.
- Full Text:
- Date Issued: 2011
- Authors: Botha, Adele
- Date: 2011
- Subjects: Mathematics -- Study and teaching , Mathematics , Mathematics -- Handbooks, manuals, etc , Mathematics teachers
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9499 , http://hdl.handle.net/10948/d1008176 , Mathematics -- Study and teaching , Mathematics , Mathematics -- Handbooks, manuals, etc , Mathematics teachers
- Description: Mathematics is regarded as a driving force in economies worldwide. The performance of South African learners in mathematics over the past decade has highlighted that problems are being experienced across all grades. This situation needs to be addressed with urgency. The South African Department of Education stated that quality learning must be the objective for all grades. The implementation of good teaching practices plays a crucial role in improving the quality of education and in guiding learners towards quality learning. To achieve quality mathematics teaching and learning it is imperative to determine what good mathematics teaching practices are. The identification of good mathematic teaching practices will provide a yard stick to measure the mathematics teaching competency of teachers. This study identifies a set of good mathematics teaching practice indicators and evidences applicable to teachers in the Intermediate phase as a first contribution. These indicators and evidences frame the second research contribution: an assessment instrument entitled “A Classroom Observation Tool for Observing Mathematics Teaching Practices in Primary Schools”. As a third research contribution a generic profile of a Grade four mathematics teacher has been built. This generic profile has been built through an analysis of data gathered by means of self-assessment questionnaires completed by the research sample, as well as through applying the observation tool. The value of the generic profile lies in the identification of shared strengths and shared improvement opportunities in the mathematics teaching practice of the sample and as such, it forms the basis of a theory on Grade four mathematics teaching practice. The fourth research contribution is the design and application of an intervention that addresses the shared improvement opportunities. The research study concludes by comparing pre-intervention classroom observation data with post-intervention classroom observation data and reporting on the impact of the intervention.
- Full Text:
- Date Issued: 2011
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
Aspects of prostacyclin in experimental hypertension
- Authors: Botha, Julia Hilary
- Date: 1983
- Subjects: Prostacyclin Prostaglandins Prostaglandin endoperoxides Thromboxanes Hypertension
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3825 , http://hdl.handle.net/10962/d1006109
- Description: A new prostaglandin - prostaglandin X (later renamed prostacyclin or prostaglandin I₂ (PGI₂)), was discovered by Moncada, Gryglewski, Bunting and Vane in 1976. This unstable substance was shown to be produced by vascular tissue and to be a vasodilator and the most potent endogenous inhibitor of platelet aggregation known. Because of its properties, it appeared that a lack of it may be related to the development and or maintenance of hypertension, a disorder featuring vasoconstriction and an increased tendency to arterial thrombosis. The present studies aimed to investigate this possibility using a rat model. A bioassay for prostacyclin was first perfected. This consisted of a modification of the method used by Moncada, Higgs and Vane (1977): PGI₂ released by rat aortic strips, during incubation in tris buffer, was measured by assessing the ability of the incubate to inhibit adenosine diphosphate induced aggregation of human platelets, as compared to the inhibitory effect of standard prostacyclin sodium salt. The specificity of the assay for the detection of PGI₂ was tested. The abil ity of hypertensive rat aorta to release prostacycl in was investigated in two studies. The first compared aortas of Wistar rats of the New Zealand genetically hypertensive strain (GH) with those of matched normotensive Wistar controls. In the second study, hypertension was induced by wrappi ng the ri ght kidney with surgical silk and removing the contralateral kidney. Ten weeks later, aortic generation of prostacyclin by these animals was compared with that of matched sham controls which had received identical surgical manipulation but for the application of silk to the right kidney. Contrary to expectation, in both forms of hypertension, aortas of the rats with elevated pressure produced consistently more prostacyclin than those of matched controls. In order to discover more about the relationship between elevated pressure and elevated PGI₂ production, the effect of pressure reduction with hypotensive agents on the ability of GH rat aortas to produce prostacyclin, was investigated. After pressure had been controlled within normal range for one week (achieved by oral administration of furosemide, dihydralazine and reserpine for one month), aortic PGI₂ was reduced in comparison with matched GH controls. However, the reduction was not consistent and statistical significance was not reached. Because it was subsequently reported by other workers, that some of the hypotensive agents which had been employed may effect prostaglandin levels per se, no conclusions could be drawn from this study as to any possible direct relationships between pressure and aortic prostacyclin generating capacity. A further means of reducing elevated pressure (which had no inherent effect on prostaglandin levels) was thus sought. A mechanical method was eventually selected, application of a silver clip to the aortas of GH rats, just below the diaphragm, producing an immediate reduction in pressure distal to the constriction. Eighteen hours with later, PGI₂ production by these distal aortas those of matched sham GH controls and was was compared found to be consistently reduced. These results indicate that the ability to produce PGI₂ may be influenced by prior local pressure changes and that the increased capacity of hypertensive rat aortas to generate prostacyclin may be related to the increased mechanical transmural stress consequent on elevated pressure. Since haemostatic balance must be influenced not only by vascular PGI₂ generation but also by platelet sensitivity to PGI₂, the response of GH platelets to the anti-aggregatory effect of prostacyc1in was also investigated. As it had been shown by Sinzinger, Si1berbauer, Horsch and Gall (1981) that intra-arterial infusion of PGI₂ in humans decreased platelet sensitivity to the substance, the possibility existed that platelet sensitivity in hypertension might be reduced. This hypothesis was, however, invalidated as the sensitivity of GH platelets to the anti-aggregatory effect of PGI₂ was almost identical to that of normotensive controls. The shortcomings of the methodology and the possible importance of these findings in the hypertensive animal are discussed. The idea that elevated PGI₂ in hypertension may play a protective role both with respect to platelet aggregation and in attenuating further pressure rises is considered. It is finally suggested that it will be possible to draw more accurate conclusions as to the meaning of the increased PGI₂ generation in hypertension (both in relation to vascular tone and platelet function) only when details of production of, and sensitivity to, thromboxane A₂ are known. Thromboxane A₂ (TXA₂) is a vasoconstrictor and promotor of aggregation (Hamberg, Svensson and Samuelson, 1975) and it may be that, despite elevated vascular PGI₂ generation, the TXA₂/PGI₂ balance is still tipped in favour of vasoconstriction and platelet aggregation in hypertension.
- Full Text:
- Date Issued: 1983
- Authors: Botha, Julia Hilary
- Date: 1983
- Subjects: Prostacyclin Prostaglandins Prostaglandin endoperoxides Thromboxanes Hypertension
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3825 , http://hdl.handle.net/10962/d1006109
- Description: A new prostaglandin - prostaglandin X (later renamed prostacyclin or prostaglandin I₂ (PGI₂)), was discovered by Moncada, Gryglewski, Bunting and Vane in 1976. This unstable substance was shown to be produced by vascular tissue and to be a vasodilator and the most potent endogenous inhibitor of platelet aggregation known. Because of its properties, it appeared that a lack of it may be related to the development and or maintenance of hypertension, a disorder featuring vasoconstriction and an increased tendency to arterial thrombosis. The present studies aimed to investigate this possibility using a rat model. A bioassay for prostacyclin was first perfected. This consisted of a modification of the method used by Moncada, Higgs and Vane (1977): PGI₂ released by rat aortic strips, during incubation in tris buffer, was measured by assessing the ability of the incubate to inhibit adenosine diphosphate induced aggregation of human platelets, as compared to the inhibitory effect of standard prostacyclin sodium salt. The specificity of the assay for the detection of PGI₂ was tested. The abil ity of hypertensive rat aorta to release prostacycl in was investigated in two studies. The first compared aortas of Wistar rats of the New Zealand genetically hypertensive strain (GH) with those of matched normotensive Wistar controls. In the second study, hypertension was induced by wrappi ng the ri ght kidney with surgical silk and removing the contralateral kidney. Ten weeks later, aortic generation of prostacyclin by these animals was compared with that of matched sham controls which had received identical surgical manipulation but for the application of silk to the right kidney. Contrary to expectation, in both forms of hypertension, aortas of the rats with elevated pressure produced consistently more prostacyclin than those of matched controls. In order to discover more about the relationship between elevated pressure and elevated PGI₂ production, the effect of pressure reduction with hypotensive agents on the ability of GH rat aortas to produce prostacyclin, was investigated. After pressure had been controlled within normal range for one week (achieved by oral administration of furosemide, dihydralazine and reserpine for one month), aortic PGI₂ was reduced in comparison with matched GH controls. However, the reduction was not consistent and statistical significance was not reached. Because it was subsequently reported by other workers, that some of the hypotensive agents which had been employed may effect prostaglandin levels per se, no conclusions could be drawn from this study as to any possible direct relationships between pressure and aortic prostacyclin generating capacity. A further means of reducing elevated pressure (which had no inherent effect on prostaglandin levels) was thus sought. A mechanical method was eventually selected, application of a silver clip to the aortas of GH rats, just below the diaphragm, producing an immediate reduction in pressure distal to the constriction. Eighteen hours with later, PGI₂ production by these distal aortas those of matched sham GH controls and was was compared found to be consistently reduced. These results indicate that the ability to produce PGI₂ may be influenced by prior local pressure changes and that the increased capacity of hypertensive rat aortas to generate prostacyclin may be related to the increased mechanical transmural stress consequent on elevated pressure. Since haemostatic balance must be influenced not only by vascular PGI₂ generation but also by platelet sensitivity to PGI₂, the response of GH platelets to the anti-aggregatory effect of prostacyc1in was also investigated. As it had been shown by Sinzinger, Si1berbauer, Horsch and Gall (1981) that intra-arterial infusion of PGI₂ in humans decreased platelet sensitivity to the substance, the possibility existed that platelet sensitivity in hypertension might be reduced. This hypothesis was, however, invalidated as the sensitivity of GH platelets to the anti-aggregatory effect of PGI₂ was almost identical to that of normotensive controls. The shortcomings of the methodology and the possible importance of these findings in the hypertensive animal are discussed. The idea that elevated PGI₂ in hypertension may play a protective role both with respect to platelet aggregation and in attenuating further pressure rises is considered. It is finally suggested that it will be possible to draw more accurate conclusions as to the meaning of the increased PGI₂ generation in hypertension (both in relation to vascular tone and platelet function) only when details of production of, and sensitivity to, thromboxane A₂ are known. Thromboxane A₂ (TXA₂) is a vasoconstrictor and promotor of aggregation (Hamberg, Svensson and Samuelson, 1975) and it may be that, despite elevated vascular PGI₂ generation, the TXA₂/PGI₂ balance is still tipped in favour of vasoconstriction and platelet aggregation in hypertension.
- Full Text:
- Date Issued: 1983
A gatherer’s paradise? early humans and plant foraging on the Cape south coast, South Africa
- Authors: Botha, Maria Susan
- Date: 2019
- Subjects: Plant remains (Archaeology) -- South Africa , Plant physiology Plant ecology Botany -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/37139 , vital:34124
- Description: Humans were driven to refugia during the cold and dry glacial Marine Isotope Stage 6 (MIS6) (~195–125 ka); only a few places, including the Cape south coast, show archaeological evidence of continuous human occupation. It has been hypothesised that the Cape south coast provided the requisite shelter to ensure human’s earliest survival because it provided all the right ingredients. The shores offer abundant shellfish, the land a diverse array of plants, and the climate was ameliorated due to the proximity of the then exposed Palaeo-Agulhas Plain to the warm Agulhas current. The aim of this study is to determine whether the indigenous flora of this region could have provided a sufficient edible resource for early humans. Residents of the Cape south coast have genetic ancestry linking them to the Khoe-San, the original inhabitants of the area, and still have an extensive knowledge of the local edible plants. With their help, I set out to determine a) whether humans have been utilising the same plant species over time, b) what the foraging potential of the edible plants in the region is and c) how resilient these plants are to human foraging. If we know whether the plant species known and used today were the same as those that were utilised by past humans, we can then use the contemporary knowledge to make predictions about past utilisation. To answer this question, I collated two databases: archaeological (all plant species found in archaeological sites [dating 0 to 80,000 BP]) and contemporary (all plant species in the modern-day ethnographic literature [last 400 years]) that occur within the Greater Cape Floristic Region(GCFR). I found a significant number of plant species shared between the two databases, which suggests that at least some plant species have been used by humans over a long period of time. To determine the indigenous plant foraging potential of the region, I foraged for food in the Cape south coast (451 bouts) monthly over a two-year period with the help of local inhabitants. The findings show that edible plant resources are distributed patchily and focusing on specific vegetation types would greatly enhance chances of harvesting 2,000 kcal per day, which is considered the daily calorific requirements for a typical hunter-gatherer. I then sought to understand how resilient these plants [(with an emphasis on plants with an underground storage organ (USO)] would be to human foraging. To do this, I set out plots and harvested all edible foods for three consecutive years with the help of foragers. Results indicate that there was a significant reduction in edible weight only in the third year of consecutive harvesting. In conclusion, using various approaches, this study investigates the plant food potential of the Cape south coast from the perspective of early human consumers. The findings suggest that knowledge regarding useful plants dates back to at least 80,000 BP. Food resources are patchily distributed across the main vegetation types found within the Cape south coast and occur in hotspots, i.e. concentrated areas hosting high densities of edible plant foods, surrounded by areas with very low plant food densities. Foragers could have harvested their daily calorific quota more easily if they focused their harvesting efforts in specific vegetation types found in the Cape south coast. Furthermore, many USOs circumvent climatic fluctuations, herbivory or both by staggering their emergence over multiple years, which implies they have some resilience to human foraging.
- Full Text:
- Date Issued: 2019
- Authors: Botha, Maria Susan
- Date: 2019
- Subjects: Plant remains (Archaeology) -- South Africa , Plant physiology Plant ecology Botany -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/37139 , vital:34124
- Description: Humans were driven to refugia during the cold and dry glacial Marine Isotope Stage 6 (MIS6) (~195–125 ka); only a few places, including the Cape south coast, show archaeological evidence of continuous human occupation. It has been hypothesised that the Cape south coast provided the requisite shelter to ensure human’s earliest survival because it provided all the right ingredients. The shores offer abundant shellfish, the land a diverse array of plants, and the climate was ameliorated due to the proximity of the then exposed Palaeo-Agulhas Plain to the warm Agulhas current. The aim of this study is to determine whether the indigenous flora of this region could have provided a sufficient edible resource for early humans. Residents of the Cape south coast have genetic ancestry linking them to the Khoe-San, the original inhabitants of the area, and still have an extensive knowledge of the local edible plants. With their help, I set out to determine a) whether humans have been utilising the same plant species over time, b) what the foraging potential of the edible plants in the region is and c) how resilient these plants are to human foraging. If we know whether the plant species known and used today were the same as those that were utilised by past humans, we can then use the contemporary knowledge to make predictions about past utilisation. To answer this question, I collated two databases: archaeological (all plant species found in archaeological sites [dating 0 to 80,000 BP]) and contemporary (all plant species in the modern-day ethnographic literature [last 400 years]) that occur within the Greater Cape Floristic Region(GCFR). I found a significant number of plant species shared between the two databases, which suggests that at least some plant species have been used by humans over a long period of time. To determine the indigenous plant foraging potential of the region, I foraged for food in the Cape south coast (451 bouts) monthly over a two-year period with the help of local inhabitants. The findings show that edible plant resources are distributed patchily and focusing on specific vegetation types would greatly enhance chances of harvesting 2,000 kcal per day, which is considered the daily calorific requirements for a typical hunter-gatherer. I then sought to understand how resilient these plants [(with an emphasis on plants with an underground storage organ (USO)] would be to human foraging. To do this, I set out plots and harvested all edible foods for three consecutive years with the help of foragers. Results indicate that there was a significant reduction in edible weight only in the third year of consecutive harvesting. In conclusion, using various approaches, this study investigates the plant food potential of the Cape south coast from the perspective of early human consumers. The findings suggest that knowledge regarding useful plants dates back to at least 80,000 BP. Food resources are patchily distributed across the main vegetation types found within the Cape south coast and occur in hotspots, i.e. concentrated areas hosting high densities of edible plant foods, surrounded by areas with very low plant food densities. Foragers could have harvested their daily calorific quota more easily if they focused their harvesting efforts in specific vegetation types found in the Cape south coast. Furthermore, many USOs circumvent climatic fluctuations, herbivory or both by staggering their emergence over multiple years, which implies they have some resilience to human foraging.
- Full Text:
- Date Issued: 2019
Characterisation of the plasmodium falciparum Hsp40 chaperones and their partnerships with Hsp70
- Authors: Botha, Melissa
- Date: 2009
- Subjects: Heat shock proteins Plasmodium falciparum Protein folding Molecular chaperones Malaria
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3938 , http://hdl.handle.net/10962/d1003997
- Description: Central to this research, 40 kDa Heat shock proteins (Hsp40s) are known to partner (or cochaperone) 70 kDa Heat shock proteins (Hsp70s), facilitating the selection and transfer of protein substrate to Hsp70 and the stimulation of the protein folding ability of Hsp70. Members of the diverse Hsp70-Hsp40 protein complement of Plasmodium falciparum have been implicated in the cytoprotection of this malaria parasite, and are thought to facilitate the protein folding, assembly and translocation tasks required by the parasite to commandeer the infected human erythrocyte subsequent to invasion. In particular, the parasite has evolved an expanded and specialised 43- member suite of Hsp40 proteins, 19 of which bear an identifiable export motif for secretion into the infected erythrocyte cytoplasm where they potentially interact with human Hsp70. Although type I Hsp40 proteins are representative of typical regulators of Hsp70 activity, only two of these proteins are apparent in the parasite’s Hsp40 complement. These include a characteristic type I Hsp40 termed PfHsp40, and a larger, atypical type I Hsp40 termed Pfj1. Both Hsp40 proteins are predicted to be parasite-resident and are most likely to facilitate the co-chaperone regulation of the highly abundant and stress-inducible Hsp70 homolog, PfHsp70-I. In this work, the co-chaperone functionality of PfHsp40 and Pfj1 was elucidated using in vivo and in vitro assays. Purified recombinant PfHsp40 was shown to stimulate the ATPase activity of PfHsp70-I in in vitro single turnover and steady state ATPase assays, and co-operate with PfHsp70-I in in vitro aggregation suppression assays. In these in vitro assays, heterologous partnerships could be demonstrated between PfHsp70-I and the human Hsp40, Hsj1a, and human Hsp70 and PfHsp40, suggesting a common mode of Hsp70-Hsp40 interaction in the parasite and host organism. The functionality of the signature Hsp40 domain, the Jdomain, of Pfj1 was demonstrated by its ability to replace the equivalent domain of the A. tumefaciens Hsp40, Agt DnaJ, in interactions with the prokaryotic Hsp70, DnaK, in the thermosensitive dnaJ cbpA E. coli OD259 deletion strain. An H33Q mutation introduced into the invariant and crucial HPD tripeptide motif abrogated the functionality of the J-domain in the in vivo complementation system. These findings provide the first evidence for the conservation of the prototypical mode of J-domain based interaction of Hsp40 with Hsp70 in P. falciparum. Immunofluorescence staining revealed the localisation of PfHsp40 to the parasite cytoplasm, and Pfj1 to the parasite cytoplasm and nucleus in cultured intraerythrocytic stage P. falciparum parasites. PfHsp70-I was also shown to localise to the parasite cytoplasm and nucleus in these stages, consistent with the literature. Overall we propose that PfHsp40 and Pfj1 co-localise with and regulate the chaperone activity of PfHsp70-I in P. falciparum. This is the first study to identify and provide evidence for a functional Hsp70-Hsp40 partnership in P. falciparum, and provides a platform for future studies to elucidate the importance of these chaperone partnerships in the establishment and survival of the parasite in the intraerythrocytic-stages of development.
- Full Text:
- Date Issued: 2009
- Authors: Botha, Melissa
- Date: 2009
- Subjects: Heat shock proteins Plasmodium falciparum Protein folding Molecular chaperones Malaria
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3938 , http://hdl.handle.net/10962/d1003997
- Description: Central to this research, 40 kDa Heat shock proteins (Hsp40s) are known to partner (or cochaperone) 70 kDa Heat shock proteins (Hsp70s), facilitating the selection and transfer of protein substrate to Hsp70 and the stimulation of the protein folding ability of Hsp70. Members of the diverse Hsp70-Hsp40 protein complement of Plasmodium falciparum have been implicated in the cytoprotection of this malaria parasite, and are thought to facilitate the protein folding, assembly and translocation tasks required by the parasite to commandeer the infected human erythrocyte subsequent to invasion. In particular, the parasite has evolved an expanded and specialised 43- member suite of Hsp40 proteins, 19 of which bear an identifiable export motif for secretion into the infected erythrocyte cytoplasm where they potentially interact with human Hsp70. Although type I Hsp40 proteins are representative of typical regulators of Hsp70 activity, only two of these proteins are apparent in the parasite’s Hsp40 complement. These include a characteristic type I Hsp40 termed PfHsp40, and a larger, atypical type I Hsp40 termed Pfj1. Both Hsp40 proteins are predicted to be parasite-resident and are most likely to facilitate the co-chaperone regulation of the highly abundant and stress-inducible Hsp70 homolog, PfHsp70-I. In this work, the co-chaperone functionality of PfHsp40 and Pfj1 was elucidated using in vivo and in vitro assays. Purified recombinant PfHsp40 was shown to stimulate the ATPase activity of PfHsp70-I in in vitro single turnover and steady state ATPase assays, and co-operate with PfHsp70-I in in vitro aggregation suppression assays. In these in vitro assays, heterologous partnerships could be demonstrated between PfHsp70-I and the human Hsp40, Hsj1a, and human Hsp70 and PfHsp40, suggesting a common mode of Hsp70-Hsp40 interaction in the parasite and host organism. The functionality of the signature Hsp40 domain, the Jdomain, of Pfj1 was demonstrated by its ability to replace the equivalent domain of the A. tumefaciens Hsp40, Agt DnaJ, in interactions with the prokaryotic Hsp70, DnaK, in the thermosensitive dnaJ cbpA E. coli OD259 deletion strain. An H33Q mutation introduced into the invariant and crucial HPD tripeptide motif abrogated the functionality of the J-domain in the in vivo complementation system. These findings provide the first evidence for the conservation of the prototypical mode of J-domain based interaction of Hsp40 with Hsp70 in P. falciparum. Immunofluorescence staining revealed the localisation of PfHsp40 to the parasite cytoplasm, and Pfj1 to the parasite cytoplasm and nucleus in cultured intraerythrocytic stage P. falciparum parasites. PfHsp70-I was also shown to localise to the parasite cytoplasm and nucleus in these stages, consistent with the literature. Overall we propose that PfHsp40 and Pfj1 co-localise with and regulate the chaperone activity of PfHsp70-I in P. falciparum. This is the first study to identify and provide evidence for a functional Hsp70-Hsp40 partnership in P. falciparum, and provides a platform for future studies to elucidate the importance of these chaperone partnerships in the establishment and survival of the parasite in the intraerythrocytic-stages of development.
- Full Text:
- Date Issued: 2009
The in vitro biological activities of three Hypoxis species and their active compounds
- Authors: Boukes, Gerhardt Johannes
- Date: 2010
- Subjects: Potatoes -- Africa , Potatoes -- Therapeutic use , Medicinal plants
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10322 , http://hdl.handle.net/10948/1228 , Potatoes -- Africa , Potatoes -- Therapeutic use , Medicinal plants
- Description: The African potato is used as an African traditional medicine for its nutritional and medicinal properties. Most research has been carried out on H. hemerocallidea, with very little or nothing on other Hypoxis spp. The main aim of this project was to provide scientific data on the anticancer, anti-inflammatory and antioxidant properties of H. hemerocallidea, H. stellipilis and H. sobolifera chloroform extracts and their active compounds. The hypoxoside and phytosterol contents of the three Hypoxis spp. were determined using TLC, HPLC and GC. H. hemerocallidea and H. sobolifera chloroform extracts contained the highest amounts of hypoxoside and β-sitosterol, respectively. For the anticancer properties, cytotoxicity of the Hypoxis extracts and its purified compounds were determined against the HeLa, HT-29 and MCF-7 cancer cell lines (using MTT), and PBMCs (using CellTiter-Blue®). H. sobolifera had the best cytotoxicity against the three cancer cell lines, whereas H. stellipilis stimulated HeLa and HT-29 cancer cell growth. IC50 values of hypoxoside and rooperol were determined. DNA cell cycle arrest (using PI staining) occurred in the late G1/early S (confirmed by increased p21Waf1/Cip1 expression) and G2/M phases after 15 and 48 hrs, respectively, when treated with Hypoxis extracts and rooperol. H. sobolifera and rooperol activated caspase-3 and -7 (using fluorescently labelled antibodies) in HeLa and HT-29 cancer cells, and caspase-7 in MCF-7 cancer cells after 48 hrs. Annexin V binding to phosphatidylserines in rooperol treated U937 cells confirmed early apoptosis after 15 hrs. The TUNEL assay showed DNA fragmentation in the three cancer cell lines when treated with H. sobolifera and rooperol for 48 hrs. A shift pass the G2/M phase has led to the investigation of endoreduplication, which was confirmed by cell/nucleus size, and anti-apoptotic proteins (Akt, phospho-Akt, phospho-Bcl-2 and p21Waf1/Cip1). U937 cell differentiation to monocyte-macrophages was optimized using PMA and 1,25(OH)2D3, which was confirmed by morphological and biochemical changes. For the anti-inflammatory properties, Hypoxis extracts and rooperol significantly increased NO production in monocyte-macrophages (pre-loaded with DAF-2 DA) and phagocytosis of pHrodoTM E. coli BioParticles®. The treatments had no effect on COX-2 expression in monocyte-macrophages. The phytosterols significantly increased IL-1β and IL-6 secretion xv (using the FlowCytomix Multiplex human Th1/Th2 10plex Kit I) in the PBMCs of one donor. For the antioxidant properties, Hypoxis extracts and rooperol significantly increased ROS production in undifferentiated and differentiated U937 cells, which were pre-loaded with DCFH-DA. Hypoxis extracts and purified compounds had ferric reducing activities, but only rooperol had ferric reducing activities significantly greater than ascorbic acid. β-sitosterol, campesterol and cholesterol significantly increased SOD activity in Chang liver cells, while H. stellipilis, H. sobolifera and rooperol decreased SOD activity. Anticancer, anti-inflammatory and antioxidant properties of the Hypoxis extracts may be attributed to the β-sitosterol content, because Hypoxis chloroform extracts contained very little or no hypoxoside. Unidentified compounds, and synergistic and additive effects of the compounds may have contributed to the biological effects. This study confirms previous reports that rooperol is the active compound. Results provide scientific data on the medicinal properties of one of the most frequently used medicinal plants in South Africa.
- Full Text:
- Date Issued: 2010
- Authors: Boukes, Gerhardt Johannes
- Date: 2010
- Subjects: Potatoes -- Africa , Potatoes -- Therapeutic use , Medicinal plants
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10322 , http://hdl.handle.net/10948/1228 , Potatoes -- Africa , Potatoes -- Therapeutic use , Medicinal plants
- Description: The African potato is used as an African traditional medicine for its nutritional and medicinal properties. Most research has been carried out on H. hemerocallidea, with very little or nothing on other Hypoxis spp. The main aim of this project was to provide scientific data on the anticancer, anti-inflammatory and antioxidant properties of H. hemerocallidea, H. stellipilis and H. sobolifera chloroform extracts and their active compounds. The hypoxoside and phytosterol contents of the three Hypoxis spp. were determined using TLC, HPLC and GC. H. hemerocallidea and H. sobolifera chloroform extracts contained the highest amounts of hypoxoside and β-sitosterol, respectively. For the anticancer properties, cytotoxicity of the Hypoxis extracts and its purified compounds were determined against the HeLa, HT-29 and MCF-7 cancer cell lines (using MTT), and PBMCs (using CellTiter-Blue®). H. sobolifera had the best cytotoxicity against the three cancer cell lines, whereas H. stellipilis stimulated HeLa and HT-29 cancer cell growth. IC50 values of hypoxoside and rooperol were determined. DNA cell cycle arrest (using PI staining) occurred in the late G1/early S (confirmed by increased p21Waf1/Cip1 expression) and G2/M phases after 15 and 48 hrs, respectively, when treated with Hypoxis extracts and rooperol. H. sobolifera and rooperol activated caspase-3 and -7 (using fluorescently labelled antibodies) in HeLa and HT-29 cancer cells, and caspase-7 in MCF-7 cancer cells after 48 hrs. Annexin V binding to phosphatidylserines in rooperol treated U937 cells confirmed early apoptosis after 15 hrs. The TUNEL assay showed DNA fragmentation in the three cancer cell lines when treated with H. sobolifera and rooperol for 48 hrs. A shift pass the G2/M phase has led to the investigation of endoreduplication, which was confirmed by cell/nucleus size, and anti-apoptotic proteins (Akt, phospho-Akt, phospho-Bcl-2 and p21Waf1/Cip1). U937 cell differentiation to monocyte-macrophages was optimized using PMA and 1,25(OH)2D3, which was confirmed by morphological and biochemical changes. For the anti-inflammatory properties, Hypoxis extracts and rooperol significantly increased NO production in monocyte-macrophages (pre-loaded with DAF-2 DA) and phagocytosis of pHrodoTM E. coli BioParticles®. The treatments had no effect on COX-2 expression in monocyte-macrophages. The phytosterols significantly increased IL-1β and IL-6 secretion xv (using the FlowCytomix Multiplex human Th1/Th2 10plex Kit I) in the PBMCs of one donor. For the antioxidant properties, Hypoxis extracts and rooperol significantly increased ROS production in undifferentiated and differentiated U937 cells, which were pre-loaded with DCFH-DA. Hypoxis extracts and purified compounds had ferric reducing activities, but only rooperol had ferric reducing activities significantly greater than ascorbic acid. β-sitosterol, campesterol and cholesterol significantly increased SOD activity in Chang liver cells, while H. stellipilis, H. sobolifera and rooperol decreased SOD activity. Anticancer, anti-inflammatory and antioxidant properties of the Hypoxis extracts may be attributed to the β-sitosterol content, because Hypoxis chloroform extracts contained very little or no hypoxoside. Unidentified compounds, and synergistic and additive effects of the compounds may have contributed to the biological effects. This study confirms previous reports that rooperol is the active compound. Results provide scientific data on the medicinal properties of one of the most frequently used medicinal plants in South Africa.
- Full Text:
- Date Issued: 2010
"I felt that I deserved it" : an Investigation into HIV-related PTSD, traumatic life events, and the personal experiences of living with HIV : a mixed-method study
- Authors: Boulind, Melissa Jane
- Date: 2014
- Subjects: Post-traumatic stress disorder -- Psychological aspects -- Research -- South Africa -- Kwazulu HIV infections -- Psychological aspects -- Research -- South Africa -- Kwazulu HIV-positive persons -- South Africa -- Kwazulu -- Interviews Psychic trauma -- Research Stress (Psychology) -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3211 , http://hdl.handle.net/10962/d1012172
- Description: There appears to be a growing body of literature focusing on PTSD and HIV-related PTSD (the diagnosis of HIV being the significant traumatic event) amongst HIV-positive samples, but only a few African studies that attempt to estimate the prevalence of PTSD amongst HIV-positive people, and even fewer that attempt to estimate the prevalence of HIV-related PTSD. The systemic review presented in this study is currently fully inclusive and is the most up-to-date available. Estimates of the prevalence of PTSD and HIV-related PTSD in South Africa range from 0.7 to 54.1% and, 4.2 to 40% respectively. The current cross-sectional study made use of a mixed-method approach to investigate traumatic life events, PTSD and HIV-related PTSD within a primary health-care centre in KwaZulu-Natal. The quantitative sample consisted of 159 adults (18-50 years) who were compliant on ARV medication. Using the CIDI-PTSD module, the adapted CIDI-PTSD module for HIV, and IES-R, findings indicated that 62% had reported some kind of traumatic event in their lifetime, with 29.6% of participants meeting the criteria for lifetime PTSD, and 40.9% meeting the criteria for lifetime HIV-related PTSD. Altogether, 57.9% of individuals met the criteria for some form of PTSD (either regular PTSD or HIV-related PTSD), and 12.6% met the criteria for both PTSD and HIV-related PTSD. Of the different categories of traumatic events, interpersonal violence has the highest rate of PTSD, followed by a diagnosis of and living with HIV, and then disaster. Furthermore, the IES-R was compared for its usefulness as a screening measure for PTSD against both the CIDI, but results suggest that it is an inferior screening measure to the PDS. The qualitative study consisted of six participants who were examined using IPA methodology informed by the Ehlers and Clark (2000) Model of trauma. Their experiences revealed experiences of stigma, a number of negative appraisals, negative emotions and coping behaviours. Some of the latter might serve as compensatory mechanisms to avoid negative judgements. Hypervigilance seems to be a feature of ARV-compliance that might confer added vulnerability to PTSD and other anxiety disorders.
- Full Text:
- Date Issued: 2014
- Authors: Boulind, Melissa Jane
- Date: 2014
- Subjects: Post-traumatic stress disorder -- Psychological aspects -- Research -- South Africa -- Kwazulu HIV infections -- Psychological aspects -- Research -- South Africa -- Kwazulu HIV-positive persons -- South Africa -- Kwazulu -- Interviews Psychic trauma -- Research Stress (Psychology) -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3211 , http://hdl.handle.net/10962/d1012172
- Description: There appears to be a growing body of literature focusing on PTSD and HIV-related PTSD (the diagnosis of HIV being the significant traumatic event) amongst HIV-positive samples, but only a few African studies that attempt to estimate the prevalence of PTSD amongst HIV-positive people, and even fewer that attempt to estimate the prevalence of HIV-related PTSD. The systemic review presented in this study is currently fully inclusive and is the most up-to-date available. Estimates of the prevalence of PTSD and HIV-related PTSD in South Africa range from 0.7 to 54.1% and, 4.2 to 40% respectively. The current cross-sectional study made use of a mixed-method approach to investigate traumatic life events, PTSD and HIV-related PTSD within a primary health-care centre in KwaZulu-Natal. The quantitative sample consisted of 159 adults (18-50 years) who were compliant on ARV medication. Using the CIDI-PTSD module, the adapted CIDI-PTSD module for HIV, and IES-R, findings indicated that 62% had reported some kind of traumatic event in their lifetime, with 29.6% of participants meeting the criteria for lifetime PTSD, and 40.9% meeting the criteria for lifetime HIV-related PTSD. Altogether, 57.9% of individuals met the criteria for some form of PTSD (either regular PTSD or HIV-related PTSD), and 12.6% met the criteria for both PTSD and HIV-related PTSD. Of the different categories of traumatic events, interpersonal violence has the highest rate of PTSD, followed by a diagnosis of and living with HIV, and then disaster. Furthermore, the IES-R was compared for its usefulness as a screening measure for PTSD against both the CIDI, but results suggest that it is an inferior screening measure to the PDS. The qualitative study consisted of six participants who were examined using IPA methodology informed by the Ehlers and Clark (2000) Model of trauma. Their experiences revealed experiences of stigma, a number of negative appraisals, negative emotions and coping behaviours. Some of the latter might serve as compensatory mechanisms to avoid negative judgements. Hypervigilance seems to be a feature of ARV-compliance that might confer added vulnerability to PTSD and other anxiety disorders.
- Full Text:
- Date Issued: 2014
F C Erasmus and the politics of South African defence, 1948-1959
- Authors: Boulter, Roger Stephen
- Date: 1998
- Subjects: Erasmus, F C (Francois Christiaan) South Africa -- Politics and government -- 1948-1961 South Africa -- Armed Forces -- History South Africa -- Military policy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2534 , http://hdl.handle.net/10962/d1002386
- Description: FC Erasmus became South Africa's defence minister in 1948 after two decades as a leading political organiser for the National Party. Although an architect of the Nationalists' post-war election victory he was not considered a minister of the first rank. Erasmus initiated a process of ridding the defence force of officers who he believed were associated with the Smuts government and replacing them with party supporters. As a result the military often lost experienced and talented officers. Erasmus felt that the armed services had been too British in ethos and appearance. He inaugurated tighter regulations on bi-lingualism, reintroduced boer rank titles, launched new uniforms and original medals and decorations, to the acclaim of the volk. His purpose was to have a defence force which was uniquely South African. Many of his policies came under attack not only from the United Party but also groups such as the Torch Commando and the veterans organisations. With the apparent lack of an imminent military threat to the apartheid government Erasmus never received substantial budgetary allocations from finance ministers. The defence force, one without conscription, remained small with largely antiquated equipment for the important air and land forces. However by the decade's end the navy was gradually receiving modern ships under the terms of the Simonstown agreement, which Erasmus had negotiated with Britain. The events of the Sharpeville crisis, just after Erasmus left defence, demonstrated that the armed forces as moulded by the minister were in poor condition to assist the civil power in suppressing disturbances. Overseas Erasmus hoped to increase the acceptability of the Union as a defence partner among Western countries by providing personnel for the Berlin Air Lift and the Korean conflict and promising a contingent for the Middle East. He attempted unsuccessfully to instigate anti-communist alliances for the land and maritime defence of Africa when the European powers were leaving the continent. These actions were primarily to obtain political support for the Union, whose prestige was rapidly decreasing as apartheid became better known. The external initiatives with the exception of the Simonstown naval agreements were not lasting.
- Full Text:
- Date Issued: 1998
- Authors: Boulter, Roger Stephen
- Date: 1998
- Subjects: Erasmus, F C (Francois Christiaan) South Africa -- Politics and government -- 1948-1961 South Africa -- Armed Forces -- History South Africa -- Military policy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2534 , http://hdl.handle.net/10962/d1002386
- Description: FC Erasmus became South Africa's defence minister in 1948 after two decades as a leading political organiser for the National Party. Although an architect of the Nationalists' post-war election victory he was not considered a minister of the first rank. Erasmus initiated a process of ridding the defence force of officers who he believed were associated with the Smuts government and replacing them with party supporters. As a result the military often lost experienced and talented officers. Erasmus felt that the armed services had been too British in ethos and appearance. He inaugurated tighter regulations on bi-lingualism, reintroduced boer rank titles, launched new uniforms and original medals and decorations, to the acclaim of the volk. His purpose was to have a defence force which was uniquely South African. Many of his policies came under attack not only from the United Party but also groups such as the Torch Commando and the veterans organisations. With the apparent lack of an imminent military threat to the apartheid government Erasmus never received substantial budgetary allocations from finance ministers. The defence force, one without conscription, remained small with largely antiquated equipment for the important air and land forces. However by the decade's end the navy was gradually receiving modern ships under the terms of the Simonstown agreement, which Erasmus had negotiated with Britain. The events of the Sharpeville crisis, just after Erasmus left defence, demonstrated that the armed forces as moulded by the minister were in poor condition to assist the civil power in suppressing disturbances. Overseas Erasmus hoped to increase the acceptability of the Union as a defence partner among Western countries by providing personnel for the Berlin Air Lift and the Korean conflict and promising a contingent for the Middle East. He attempted unsuccessfully to instigate anti-communist alliances for the land and maritime defence of Africa when the European powers were leaving the continent. These actions were primarily to obtain political support for the Union, whose prestige was rapidly decreasing as apartheid became better known. The external initiatives with the exception of the Simonstown naval agreements were not lasting.
- Full Text:
- Date Issued: 1998
'n Studie van die houding en gesindheid teenoor spesiale onderwys soos geopenbaar deur 'n groep ouers van spesiale klas-leerlinge in Oos-Kaapland
- Bouwer, Jeremia Cornelius Esias
- Authors: Bouwer, Jeremia Cornelius Esias
- Date: 1979
- Subjects: Special education -- South Africa -- Eastern Cape
- Language: Afrikaans
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1361 , http://hdl.handle.net/10962/d1001427
- Description: Die weerstand wat ouers soms teen Spesiale Onderwys bied, kan stremmend inwerk op leerlinge. Om insig in die gesindheid van ouers van Spesiale Klas-Ieerlinge te verkry, is 'n gewysigde vorm van die Thurston Sentence Completion Form gebruik. Die vorms is deur ouers van leerlinge in 'n aantal Spesiale Klasse in Oos-Kaapland voltooi en die response is in positiewe en negatiewe reaksies ingedeel. Ook is elke item ontleed. Daar is tot die gevolgtrekking gekom dat die meeste ouers tog weI positief ingesteld is teenoor Spesiale Onderwys en inderdaad erkenning verleen aan die werk wat in die klasse gedoen word. Die behoefte aan 'n nouer skakeling tussen die betrokke ouers en die skole het duidelik na vore gekom
- Full Text:
- Date Issued: 1979
- Authors: Bouwer, Jeremia Cornelius Esias
- Date: 1979
- Subjects: Special education -- South Africa -- Eastern Cape
- Language: Afrikaans
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1361 , http://hdl.handle.net/10962/d1001427
- Description: Die weerstand wat ouers soms teen Spesiale Onderwys bied, kan stremmend inwerk op leerlinge. Om insig in die gesindheid van ouers van Spesiale Klas-Ieerlinge te verkry, is 'n gewysigde vorm van die Thurston Sentence Completion Form gebruik. Die vorms is deur ouers van leerlinge in 'n aantal Spesiale Klasse in Oos-Kaapland voltooi en die response is in positiewe en negatiewe reaksies ingedeel. Ook is elke item ontleed. Daar is tot die gevolgtrekking gekom dat die meeste ouers tog weI positief ingesteld is teenoor Spesiale Onderwys en inderdaad erkenning verleen aan die werk wat in die klasse gedoen word. Die behoefte aan 'n nouer skakeling tussen die betrokke ouers en die skole het duidelik na vore gekom
- Full Text:
- Date Issued: 1979
Novel aspects of platinum-amine coordination compounds: their chemistry and anticancer application
- Authors: Bouwer, Yolanda
- Date: 2008
- Subjects: Coordination compounds , Platinum compounds , Antineoplastic agents
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10444 , http://hdl.handle.net/10948/d1021052
- Description: The aim in this thesis, was to synthesize novel platinum coordination compounds, in order to develop compounds with improved anticancer action which could lead to an improved understanding of the mechanism by which they operate and at the same time, improve synthetic methods for their products. The initial work included the development of a novel synthetic method for 1R,2R-diaminocyclohexaneoxalato-platinum(II) (oxaliplatin), by using an essentially non-aqueous solvent medium and direct ligand exchange at elevated temperatures. This was done by a study of the kinetics of the reaction in a variety of conditions; such as relative reagent concentrations and ratios as well as solvent mixtures. An effective method was developed which could be applied industrially. An international patent was taken out on this method. Various amine complexes of platinum(II) were synthesized using chloro, bromo and oxalato groups as leaving groups. The non-leaving groups were selected having certain specific characteristics in mind. Novel mononitroplatinum(IV) complexes were synthesized, mostly with oxalato leaving groups. One of these in particular, had excellent anticancer behaviour. Another trichloromononitro complex was also synthesized with very good anticancer properties. Two international patents were filed for the latter two compounds. As far as possible, all compounds were studied by spectrometric, chromatographic and thermal methods. They were also tested against 3 cancer cell lines namely cervical (Hela), Colon (HT29) and Breast (MCF7) cancer cells.
- Full Text:
- Date Issued: 2008
- Authors: Bouwer, Yolanda
- Date: 2008
- Subjects: Coordination compounds , Platinum compounds , Antineoplastic agents
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10444 , http://hdl.handle.net/10948/d1021052
- Description: The aim in this thesis, was to synthesize novel platinum coordination compounds, in order to develop compounds with improved anticancer action which could lead to an improved understanding of the mechanism by which they operate and at the same time, improve synthetic methods for their products. The initial work included the development of a novel synthetic method for 1R,2R-diaminocyclohexaneoxalato-platinum(II) (oxaliplatin), by using an essentially non-aqueous solvent medium and direct ligand exchange at elevated temperatures. This was done by a study of the kinetics of the reaction in a variety of conditions; such as relative reagent concentrations and ratios as well as solvent mixtures. An effective method was developed which could be applied industrially. An international patent was taken out on this method. Various amine complexes of platinum(II) were synthesized using chloro, bromo and oxalato groups as leaving groups. The non-leaving groups were selected having certain specific characteristics in mind. Novel mononitroplatinum(IV) complexes were synthesized, mostly with oxalato leaving groups. One of these in particular, had excellent anticancer behaviour. Another trichloromononitro complex was also synthesized with very good anticancer properties. Two international patents were filed for the latter two compounds. As far as possible, all compounds were studied by spectrometric, chromatographic and thermal methods. They were also tested against 3 cancer cell lines namely cervical (Hela), Colon (HT29) and Breast (MCF7) cancer cells.
- Full Text:
- Date Issued: 2008