Evaluating the potential of monometallic and bimetallic nanomaterials as horseradish peroxidase mimetics
- Authors: Mvango, Sindisiwe
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/65134 , vital:28694
- Description: This study presents the synthesis of citrate-capped gold nanoparticles (cit-AuNPs), copper oxide nanoparticles (CuONPs), glutathione-capped gold nanoparticles (GSH-AuNPs), 4- aminothiophenol-capped gold nanoparticles (4-ATP-AuNPs), 4-mercapto benzoic acid- capped gold nanoparticles (4-MBA-AuNPs) and copper oxide gold nanoalloys (CuO-Au nanoalloys). Microscopy and spectroscopy techniques were used to confirm the successful synthesis of these nanoparticles. The synthesized nanoparticles were studied their potential applications as horseradish peroxidase (HPR) enzyme mimetics and for the detection of glucose. The cit-AuNPs and GSH-AuNPs exhibited peroxidase-like activity towards hydrogen peroxide (H2O2) with high Michaelis-Menten (Km) values of 61.5 mM and 30.8 mM, respectively. The other nanoparticles, that is, 4-ATP-AuNPs, CuONPs and CuO-Au nanoalloys gave lower Km values of 4.74 mM, 1.92 mM and 4.05 mM, respectively. The obtained Km values were comparable to those of HRP enzymes which ranged from 0.214 - 3.70 mM with 4-ATP-AuNPs and CuO-Au nanoalloys slightly higher. These values were within the reasonable experimental values of the HRP enzyme. The studies showed that the gold nanoparticles had low adsorptive efficiency towards H2O2 compared to the copper-based nanoparticles (CuONPs and CuO-Au nanoalloys). The CuO-Au nanoalloys also showed the synergistic effect between the gold and copper nanoparticles with extended linear concentration range for the quantification of H2O2. The mechanism of catalysis was confirmed using UV-vis spectroscopy and electron paramagnetic resonance (EPR) in that the generation of reactive oxygen species was observed. The use of 1,3-diphenylisobenzofuran (DPBF) as radical quencher and 5,5- dimethyl-1-pyrroline N-oxide (DMPO) as a radical scavenger confirmed the production of reductive reactive oxygen species using UV-vis and EPR studies. The rate of production of reactive oxygen species in the gold-based nanoparticles was small compared to the copper-based nanoparticles, that is CuONPs and CuO-Au (bimetallic) nanoalloys. The synthesized nanoparticles were further studied their potential use in the colorimetric detection of glucose. The copper-based nanomaterials, CuONPs and CuO-Au nanoalloys, were excellent towards detection of glucose, with a limit of detection (LoD) of 9.34 pM for CuONPs and 6.75 pM for CuO-Au nanoalloys. The linear concentration (LCR) range of CuONPs was 0 to 70 pM and for CuO-Au nanoalloys the LCR was 0.0 - 30 pM. , Thesis (MSc) -- Faculty of Science, Chemistry, 2017
- Full Text:
- Authors: Mvango, Sindisiwe
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/65134 , vital:28694
- Description: This study presents the synthesis of citrate-capped gold nanoparticles (cit-AuNPs), copper oxide nanoparticles (CuONPs), glutathione-capped gold nanoparticles (GSH-AuNPs), 4- aminothiophenol-capped gold nanoparticles (4-ATP-AuNPs), 4-mercapto benzoic acid- capped gold nanoparticles (4-MBA-AuNPs) and copper oxide gold nanoalloys (CuO-Au nanoalloys). Microscopy and spectroscopy techniques were used to confirm the successful synthesis of these nanoparticles. The synthesized nanoparticles were studied their potential applications as horseradish peroxidase (HPR) enzyme mimetics and for the detection of glucose. The cit-AuNPs and GSH-AuNPs exhibited peroxidase-like activity towards hydrogen peroxide (H2O2) with high Michaelis-Menten (Km) values of 61.5 mM and 30.8 mM, respectively. The other nanoparticles, that is, 4-ATP-AuNPs, CuONPs and CuO-Au nanoalloys gave lower Km values of 4.74 mM, 1.92 mM and 4.05 mM, respectively. The obtained Km values were comparable to those of HRP enzymes which ranged from 0.214 - 3.70 mM with 4-ATP-AuNPs and CuO-Au nanoalloys slightly higher. These values were within the reasonable experimental values of the HRP enzyme. The studies showed that the gold nanoparticles had low adsorptive efficiency towards H2O2 compared to the copper-based nanoparticles (CuONPs and CuO-Au nanoalloys). The CuO-Au nanoalloys also showed the synergistic effect between the gold and copper nanoparticles with extended linear concentration range for the quantification of H2O2. The mechanism of catalysis was confirmed using UV-vis spectroscopy and electron paramagnetic resonance (EPR) in that the generation of reactive oxygen species was observed. The use of 1,3-diphenylisobenzofuran (DPBF) as radical quencher and 5,5- dimethyl-1-pyrroline N-oxide (DMPO) as a radical scavenger confirmed the production of reductive reactive oxygen species using UV-vis and EPR studies. The rate of production of reactive oxygen species in the gold-based nanoparticles was small compared to the copper-based nanoparticles, that is CuONPs and CuO-Au (bimetallic) nanoalloys. The synthesized nanoparticles were further studied their potential use in the colorimetric detection of glucose. The copper-based nanomaterials, CuONPs and CuO-Au nanoalloys, were excellent towards detection of glucose, with a limit of detection (LoD) of 9.34 pM for CuONPs and 6.75 pM for CuO-Au nanoalloys. The linear concentration (LCR) range of CuONPs was 0 to 70 pM and for CuO-Au nanoalloys the LCR was 0.0 - 30 pM. , Thesis (MSc) -- Faculty of Science, Chemistry, 2017
- Full Text:
Evaluation of the acceptability of ambulatory blood pressure monitoring in a semi-rural, Eastern Cape population
- Authors: Chiwanza, Farisai
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/59161 , vital:27447
- Description: Expected release date-April 2019
- Full Text:
- Authors: Chiwanza, Farisai
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/59161 , vital:27447
- Description: Expected release date-April 2019
- Full Text:
Formulation development, manufacture and evaluation of hydralazine hydrochloride microspheres
- Kangausaru, Shakemore Tinashe
- Authors: Kangausaru, Shakemore Tinashe
- Date: 2017
- Subjects: Hydralazine , Microspheres , Drugs Controlled release , Drugs Design , Drug development , Hypertension Chemotherapy
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/59220 , vital:27482
- Description: Despite improvements in its detection and treatment since the 1970s, hypertension is the most common and important risk factor for cardiovascular diseases. Hypertension is a chronic condition often underdiagnosed and/or inadequately treated in Sub-Saharan Africa. Recent survey results illustrate that the condition continues to contribute significantly to mortality and morbidity in adults and that it is poorly controlled in clinical practice. Hydralazine (HYD) is used either alone or in combination for the management of chronic hypertension, chronic cardiac failure and hypertensive crises. Due to its short plasma half-life of between 2 to 4 hours, HYD is normally administered two to four times daily, therefore making it a potential candidate for inclusion in sustained release formulations. The formulation of sustained release microsphere dosage forms may be useful to improve patient adherence and to achieve predictable and optimised therapeutic plasma concentrations. A stability indicating reversed-phase high performance liquid chromatography (RP-HPLC) method for the quantitation of HYD in pharmaceutical dosage forms was developed and optimised using a Central Composite Design (CCD) approach. UV/Vis detection method was selected as HYD contains an ultraviolet light-absorbing chromophore. The method was validated with respect to linearity and range, limits of quantitation (LOQ) and detection (LOD), accuracy, precision, sensitivity, selectivity and specificity as per International Conference on Harmonisation (ICH) guidelines. The method was applied to commercially available HYD tablets. No interfering peaks were observed from excipients used in the commercially available tablets. Preformulation studies were conducted to ensure the manufacture of high quality, stable sustained release HYD microspheres. The results revealed that there was an interaction between HYD and Carbopol® 971P, therefore Carbopol® polymers were not included during formulation studies. HYD was found to be compatible with Methocel® K100LV, Eudragit® RS PO and Avicel® 101 and HYD formulations were developed and optimised using these excipients. An oil-in-oil (o/o) solvent evaporation technique was selected for the manufacture of HYD microspheres due to its simplicity and to avoid exposure of HYD to moisture that could have been encountered if a water-in-oil (w/o) manufacturing process was used. The selection of o/o solvent evaporation technique was also based on the hydrophilicity of HYD and the polymers selected. Different grades of Methocel® and Eudragit® were selected to evaluate their effect on encapsulation efficiency (EE), in vitro release and microparticle shape and morphology. The best combination of these polymers which resulted in the desired EE, in vitro release, microparticle shape and size were then selected for formulation optimisation. A numerical optimisation approach was used to predict a formulation composition that would produce minimal HYD release initially and maximum HYD release after 12 hours of dissolution testing. The release kinetics of HYD from the manufactured microspheres were established by fitting in vitro release data to several mathematical models. The in vitro release data for the optimised formulations was best described using Higuchi model. The short-term stability of the optimised formulations was established by undertaking stability studies at 4°C, 25 °C/60 % RH and 40 °C/75 % RH. The results revealed that there was no significant change in appearance and physicochemical properties of the microspheres over a period of one month. However, long-term stability studies would be required to determine the shelf-life of the formulations. In addition, a gas chromatographic (GC) method was selected for determining residual amounts of acetone and n-hexane in the optimised formulations. GC methods were developed and optimised by evaluation of process parameters. System suitability testing was performed with respect to resolution, theoretical number of plates and selectivity. Method validation was performed with respect to linearity, range, inter- and intra-day precision, retention time (Rt) precision, limit of quantitation (LOQ) and detection (LOD). A solvent extraction method was used to analyse residual solvents in the optimised formulations. The drying process was sufficient in evaporating acetone and n-hexane from the optimised formulations. Solvent evaporation technique has been successfully used in the manufacture of HYD microspheres. The microspheres have potential for further development, scale up formulation studies and long-term stability studies. , Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2017
- Full Text:
- Authors: Kangausaru, Shakemore Tinashe
- Date: 2017
- Subjects: Hydralazine , Microspheres , Drugs Controlled release , Drugs Design , Drug development , Hypertension Chemotherapy
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/59220 , vital:27482
- Description: Despite improvements in its detection and treatment since the 1970s, hypertension is the most common and important risk factor for cardiovascular diseases. Hypertension is a chronic condition often underdiagnosed and/or inadequately treated in Sub-Saharan Africa. Recent survey results illustrate that the condition continues to contribute significantly to mortality and morbidity in adults and that it is poorly controlled in clinical practice. Hydralazine (HYD) is used either alone or in combination for the management of chronic hypertension, chronic cardiac failure and hypertensive crises. Due to its short plasma half-life of between 2 to 4 hours, HYD is normally administered two to four times daily, therefore making it a potential candidate for inclusion in sustained release formulations. The formulation of sustained release microsphere dosage forms may be useful to improve patient adherence and to achieve predictable and optimised therapeutic plasma concentrations. A stability indicating reversed-phase high performance liquid chromatography (RP-HPLC) method for the quantitation of HYD in pharmaceutical dosage forms was developed and optimised using a Central Composite Design (CCD) approach. UV/Vis detection method was selected as HYD contains an ultraviolet light-absorbing chromophore. The method was validated with respect to linearity and range, limits of quantitation (LOQ) and detection (LOD), accuracy, precision, sensitivity, selectivity and specificity as per International Conference on Harmonisation (ICH) guidelines. The method was applied to commercially available HYD tablets. No interfering peaks were observed from excipients used in the commercially available tablets. Preformulation studies were conducted to ensure the manufacture of high quality, stable sustained release HYD microspheres. The results revealed that there was an interaction between HYD and Carbopol® 971P, therefore Carbopol® polymers were not included during formulation studies. HYD was found to be compatible with Methocel® K100LV, Eudragit® RS PO and Avicel® 101 and HYD formulations were developed and optimised using these excipients. An oil-in-oil (o/o) solvent evaporation technique was selected for the manufacture of HYD microspheres due to its simplicity and to avoid exposure of HYD to moisture that could have been encountered if a water-in-oil (w/o) manufacturing process was used. The selection of o/o solvent evaporation technique was also based on the hydrophilicity of HYD and the polymers selected. Different grades of Methocel® and Eudragit® were selected to evaluate their effect on encapsulation efficiency (EE), in vitro release and microparticle shape and morphology. The best combination of these polymers which resulted in the desired EE, in vitro release, microparticle shape and size were then selected for formulation optimisation. A numerical optimisation approach was used to predict a formulation composition that would produce minimal HYD release initially and maximum HYD release after 12 hours of dissolution testing. The release kinetics of HYD from the manufactured microspheres were established by fitting in vitro release data to several mathematical models. The in vitro release data for the optimised formulations was best described using Higuchi model. The short-term stability of the optimised formulations was established by undertaking stability studies at 4°C, 25 °C/60 % RH and 40 °C/75 % RH. The results revealed that there was no significant change in appearance and physicochemical properties of the microspheres over a period of one month. However, long-term stability studies would be required to determine the shelf-life of the formulations. In addition, a gas chromatographic (GC) method was selected for determining residual amounts of acetone and n-hexane in the optimised formulations. GC methods were developed and optimised by evaluation of process parameters. System suitability testing was performed with respect to resolution, theoretical number of plates and selectivity. Method validation was performed with respect to linearity, range, inter- and intra-day precision, retention time (Rt) precision, limit of quantitation (LOQ) and detection (LOD). A solvent extraction method was used to analyse residual solvents in the optimised formulations. The drying process was sufficient in evaporating acetone and n-hexane from the optimised formulations. Solvent evaporation technique has been successfully used in the manufacture of HYD microspheres. The microspheres have potential for further development, scale up formulation studies and long-term stability studies. , Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2017
- Full Text:
Formulation, development and evaluation of lipid nanocarriers for minocycline hydrochloride
- Authors: Ranchhod, Janeeta
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/65234 , vital:28712
- Description: Expected release date-May 2019
- Full Text:
- Authors: Ranchhod, Janeeta
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/65234 , vital:28712
- Description: Expected release date-May 2019
- Full Text:
Geological study and economic evaluation of the Paardeplaats Coal Exploration Project
- Authors: Gcayi, Gcobani
- Date: 2017
- Subjects: Coal Geology South Africa Mpumalanga , Coal Prospecting South Africa Mpumalanga , Coal mines and mining South Africa Mpumalanga , Geology, Economic South Africa , Coal reserves South Africa Mpumalanga
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/59183 , vital:27452
- Description: For a coal mining company the coal resources are an important asset, and they are acquired in a number of different ways, such as obtaining a prospecting permit from government or an existing permit from another entity and or purchasing an operating colliery from another entity. The Paardeplaats Project is a brownfields project located approximately 7 km south west of the town of Belfast in Mpumalanga Province, South Africa, on the far eastern edge of the Witbank Coalfield. The project is located adjacent to an operating mine, Glisa Colliery, owned by Eyesizwe Coal. Eyesizwe Coal was awarded the prospecting permit in 2006 by the Department of Mineral Resources. Subsequent exploration activities, which included airborne magnetic survey and borehole drilling, were conducted between 2008 and 2010. The results of the drilling confirmed the presence of coal resources, which are classified in the Measured, Indicated and Inferred categories. Mining and beneficiation methods from the adjacent Glisa Colliery, which has similar geology to the project area, were assumed in order to generate a coal reserve statement. The Coal Reserve qualities are suitable to the domestic market, particularly Eskom. South Africa’s coal supply is demand driven, primarily from Eskom for electricity generation followed by the export market and thirdly by Sasol for synthetic fuel generation. The majority of Eskom’s existing coal-fired power stations are located in the Mpumalanga Province, which provides a viable market for coal projects in Mpumalanga when considering existing transport infrastructure and transportation costs. Eskom’s continued demand for coal in the Mpumalanga region, at least until 2040, provides a future market for advanced coal projects in the region. A valuation of the project using the Cash Flow Approach showed the project to be economically viable. , Thesis (MSc) -- Faculty of Faculty of Science, Geology, 2017
- Full Text:
- Authors: Gcayi, Gcobani
- Date: 2017
- Subjects: Coal Geology South Africa Mpumalanga , Coal Prospecting South Africa Mpumalanga , Coal mines and mining South Africa Mpumalanga , Geology, Economic South Africa , Coal reserves South Africa Mpumalanga
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/59183 , vital:27452
- Description: For a coal mining company the coal resources are an important asset, and they are acquired in a number of different ways, such as obtaining a prospecting permit from government or an existing permit from another entity and or purchasing an operating colliery from another entity. The Paardeplaats Project is a brownfields project located approximately 7 km south west of the town of Belfast in Mpumalanga Province, South Africa, on the far eastern edge of the Witbank Coalfield. The project is located adjacent to an operating mine, Glisa Colliery, owned by Eyesizwe Coal. Eyesizwe Coal was awarded the prospecting permit in 2006 by the Department of Mineral Resources. Subsequent exploration activities, which included airborne magnetic survey and borehole drilling, were conducted between 2008 and 2010. The results of the drilling confirmed the presence of coal resources, which are classified in the Measured, Indicated and Inferred categories. Mining and beneficiation methods from the adjacent Glisa Colliery, which has similar geology to the project area, were assumed in order to generate a coal reserve statement. The Coal Reserve qualities are suitable to the domestic market, particularly Eskom. South Africa’s coal supply is demand driven, primarily from Eskom for electricity generation followed by the export market and thirdly by Sasol for synthetic fuel generation. The majority of Eskom’s existing coal-fired power stations are located in the Mpumalanga Province, which provides a viable market for coal projects in Mpumalanga when considering existing transport infrastructure and transportation costs. Eskom’s continued demand for coal in the Mpumalanga region, at least until 2040, provides a future market for advanced coal projects in the region. A valuation of the project using the Cash Flow Approach showed the project to be economically viable. , Thesis (MSc) -- Faculty of Faculty of Science, Geology, 2017
- Full Text:
Geomorphological connectivity and sensitivity examined in a recently degraded gravel-bed stream: implications for river-floodplain rehabilitation
- Authors: Powell, Rebecca
- Date: 2017
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/53722 , vital:26313
- Description: The study of river complexity and sensitivity to future human land-use activities and climate change is a fast growing field within the discipline of fluvial geomorphology. Associated with this is a need to improve river rehabilitation and catchment management approach, design and effectiveness. This study aimed to investigate drivers of the recent geomorphological sensitivity of the Baviaanskloof River-floodplain, an upland system in South Africa, by integrating the concepts of geomorphological connectivity and Panarchy. The understanding generated was used to evaluate the approach of the State agency, Working for Wetlands (WfWet), to river-floodplain rehabilitation in the catchment.The concepts of geomorphological connectivity and Panarchy provide useful frameworks for understanding interactions between geomorphological processes and structure across scales of space and time. Geomorphological connectivity explains the degree to which water and sediment is linked in a river landscape, determined by the distribution of erosional and depositional landforms (Brierley et al. 2006; Fryirs et al. 2007a; Fryirs et al. 2007b). Panarchy attempts to explain lagged response to disturbances, non-linear interactions, and sudden shifts in system state, and has been applied largely to ecological systems. Panarchy theory, when combined with the concept of geomorphological connectivity, provides a guiding framework for understanding river complexity in greater depth. The first results chapter of this study investigated river long-term and recent geomorphological history, towards understanding the nature and timing of river geomorphological cycling between erosion and deposition. Optically Stimulated Luminescence dating of alluvial fan and floodplain sedimentary units was conducted, for analysis of river-floodplain long-term history (100s to 1 000s of years). Interviews with 11 local landowners, combined with analysis of historic aerial imagery and river-floodplain topographic surveys, provided a means of describing recent (last few decades) geomorphological dynamics. The results indicated that the Baviaanskloof is naturally a cut- and-fill landscape over scales of several hundred to thousands of years, characterized by the alternation between phases of high fluvial energy and alluvial fan expansion, and low energy conditions associated with floodplain accretion. Recent and widespread river-floodplain degradation was compressed into a short period of approximately 30 years, suggesting that one or more drivers have pushed the system beyond a threshold, resulting in increased water and sediment connectivity. The second results chapter investigated the role of human land-use activities and flooding frequency and magnitude, as drivers of recent river-floodplain degradation. Human impacts were investigated by describing land-use activities for the preceding 80 years, and relating these activities to changes in river-floodplain form and behavior. Temporal trends in flood events of different frequency and magnitude were investigated by analyzing rainfall data, integrated with landowner reports of flood-inducing rainfall magnitudes. The findings indicated that human land-use activities have been an important driver of recent river- floodplain degradation, through the enhancement of water and sediment connectivity across spatial scales of the catchment. Episodic and high magnitude floods synergized with human driven increased connectivity, precipitating stream power and geomorphological threshold breaches, resulting in a shift in river behaviour. The third results chapter investigated the influence of tributary-junction streams and fans on the geomorphological form, behavior and sensitivity of the Baviaanskloof River. Local- scale topographic impacts of tributary fans and streams were described using topographic surveys and geomorphological mapping techniques. Tributary streams form a major control on the behaviour of the river, by influencing the degree of coarse sediment connectivity with the main channel. Although tributary fans buffer the river from disturbances occurring in the wider catchment, they initiate topographic variations along the floodplain, influencing local-scale patterns of deposition and erosion along the river. The main river responds to water and sediment inputs from tributary junction streams by locally adjusting longitudinal slope, maintaining an overall constant slope of 0.0066 m/m. The response of the Baviaanskloof River to tributary junction fans and streams is however variable, and is fashioned by complex interactions between geomorphological and anthropogenic factors. The final two chapters of the thesis evaluate the findings of the study within the context of river-floodplain rehabilitation approaches in South Africa, and within the theoretical, philosophical and methodological context of the research. The first of these two chapters evaluates the approach of the WfWet programme to river-floodplain rehabilitation in the Baviaanskloof. The chapter indicates that the present practice of WfWet is to reinstate a pre-degradation state, which is not suited to the Baviaanskloof River-floodplain, since the river-floodplain has passed a geomorphological threshold, resulting in a new set of interacting processes and landforms. The author presents a conceptual model illustrating the existence of geomorphological adaptive cycles interacting across spatial and temporal scales, thereby attempting to explain a river Panarchy specific to the Baviaanskloof. From this conceptual model, a hierarchical rehabilitation framework, targeting geomorphological processes and structure situated at different spatial and temporal scales of the landscape is suggested. The final chapter discusses the implications of integrating the concepts of geomorphological connectivity and river Panarchy theory in studies of river complexity and sensitivity to geomorphological change. The author suggests that there is scope for further investigation of the application of the two concepts within the discipline of fluvial geomorphology, particularly with regard to developing quantitative approaches to measuring and describing connectivity and Panarchy.
- Full Text:
- Authors: Powell, Rebecca
- Date: 2017
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/53722 , vital:26313
- Description: The study of river complexity and sensitivity to future human land-use activities and climate change is a fast growing field within the discipline of fluvial geomorphology. Associated with this is a need to improve river rehabilitation and catchment management approach, design and effectiveness. This study aimed to investigate drivers of the recent geomorphological sensitivity of the Baviaanskloof River-floodplain, an upland system in South Africa, by integrating the concepts of geomorphological connectivity and Panarchy. The understanding generated was used to evaluate the approach of the State agency, Working for Wetlands (WfWet), to river-floodplain rehabilitation in the catchment.The concepts of geomorphological connectivity and Panarchy provide useful frameworks for understanding interactions between geomorphological processes and structure across scales of space and time. Geomorphological connectivity explains the degree to which water and sediment is linked in a river landscape, determined by the distribution of erosional and depositional landforms (Brierley et al. 2006; Fryirs et al. 2007a; Fryirs et al. 2007b). Panarchy attempts to explain lagged response to disturbances, non-linear interactions, and sudden shifts in system state, and has been applied largely to ecological systems. Panarchy theory, when combined with the concept of geomorphological connectivity, provides a guiding framework for understanding river complexity in greater depth. The first results chapter of this study investigated river long-term and recent geomorphological history, towards understanding the nature and timing of river geomorphological cycling between erosion and deposition. Optically Stimulated Luminescence dating of alluvial fan and floodplain sedimentary units was conducted, for analysis of river-floodplain long-term history (100s to 1 000s of years). Interviews with 11 local landowners, combined with analysis of historic aerial imagery and river-floodplain topographic surveys, provided a means of describing recent (last few decades) geomorphological dynamics. The results indicated that the Baviaanskloof is naturally a cut- and-fill landscape over scales of several hundred to thousands of years, characterized by the alternation between phases of high fluvial energy and alluvial fan expansion, and low energy conditions associated with floodplain accretion. Recent and widespread river-floodplain degradation was compressed into a short period of approximately 30 years, suggesting that one or more drivers have pushed the system beyond a threshold, resulting in increased water and sediment connectivity. The second results chapter investigated the role of human land-use activities and flooding frequency and magnitude, as drivers of recent river-floodplain degradation. Human impacts were investigated by describing land-use activities for the preceding 80 years, and relating these activities to changes in river-floodplain form and behavior. Temporal trends in flood events of different frequency and magnitude were investigated by analyzing rainfall data, integrated with landowner reports of flood-inducing rainfall magnitudes. The findings indicated that human land-use activities have been an important driver of recent river- floodplain degradation, through the enhancement of water and sediment connectivity across spatial scales of the catchment. Episodic and high magnitude floods synergized with human driven increased connectivity, precipitating stream power and geomorphological threshold breaches, resulting in a shift in river behaviour. The third results chapter investigated the influence of tributary-junction streams and fans on the geomorphological form, behavior and sensitivity of the Baviaanskloof River. Local- scale topographic impacts of tributary fans and streams were described using topographic surveys and geomorphological mapping techniques. Tributary streams form a major control on the behaviour of the river, by influencing the degree of coarse sediment connectivity with the main channel. Although tributary fans buffer the river from disturbances occurring in the wider catchment, they initiate topographic variations along the floodplain, influencing local-scale patterns of deposition and erosion along the river. The main river responds to water and sediment inputs from tributary junction streams by locally adjusting longitudinal slope, maintaining an overall constant slope of 0.0066 m/m. The response of the Baviaanskloof River to tributary junction fans and streams is however variable, and is fashioned by complex interactions between geomorphological and anthropogenic factors. The final two chapters of the thesis evaluate the findings of the study within the context of river-floodplain rehabilitation approaches in South Africa, and within the theoretical, philosophical and methodological context of the research. The first of these two chapters evaluates the approach of the WfWet programme to river-floodplain rehabilitation in the Baviaanskloof. The chapter indicates that the present practice of WfWet is to reinstate a pre-degradation state, which is not suited to the Baviaanskloof River-floodplain, since the river-floodplain has passed a geomorphological threshold, resulting in a new set of interacting processes and landforms. The author presents a conceptual model illustrating the existence of geomorphological adaptive cycles interacting across spatial and temporal scales, thereby attempting to explain a river Panarchy specific to the Baviaanskloof. From this conceptual model, a hierarchical rehabilitation framework, targeting geomorphological processes and structure situated at different spatial and temporal scales of the landscape is suggested. The final chapter discusses the implications of integrating the concepts of geomorphological connectivity and river Panarchy theory in studies of river complexity and sensitivity to geomorphological change. The author suggests that there is scope for further investigation of the application of the two concepts within the discipline of fluvial geomorphology, particularly with regard to developing quantitative approaches to measuring and describing connectivity and Panarchy.
- Full Text:
Homecoming
- Authors: Mazwai, Nontsikelelo
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MA
- Identifier: http://hdl.handle.net/10962/164930 , vital:41185
- Description: Thesis (MA)--Rhodes University, Faculty of Humanities, School of Languages, 2017
- Full Text:
- Authors: Mazwai, Nontsikelelo
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MA
- Identifier: http://hdl.handle.net/10962/164930 , vital:41185
- Description: Thesis (MA)--Rhodes University, Faculty of Humanities, School of Languages, 2017
- Full Text:
Identification of SNPs within the CYP2A6 enzyme of TNBC cell lines and the resulting change in activity
- Dingle, Laura Margaret Kirkpatrick
- Authors: Dingle, Laura Margaret Kirkpatrick
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64349 , vital:28536
- Description: Expected release date-May 2019
- Full Text:
- Authors: Dingle, Laura Margaret Kirkpatrick
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64349 , vital:28536
- Description: Expected release date-May 2019
- Full Text:
Improving the cold tolerance of false codling moth, thaumatotibia leucotreta, for better performance in a sterile insect release programme
- Authors: Daniel, Claire Ashleigh
- Date: 2017
- Subjects: Cryptophlebia leucotreta -- South Africa , Cryptophlebia leucotreta -- Reproduction -- Effect of temperature on , Cryptophlebia leucotreta -- Biological control -- South Africa , Citrus -- Diseases and pests -- Biological control -- South Africa , Insect pests -- Biological control -- South Africa , Insecticides , Citrus fruit industry -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/5271 , vital:20803
- Description: The false codling moth (FCM), Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is a major pest of citrus and other important crops in Sub-Saharan Africa. The introduction of a sterile insect technique (SIT) programme for FCM in South Africa has proven to be very effective in the control of FCM. The objective was to flood citrus orchards with large numbers of sterile males resulting in a ratio of at least 10 sterile to 1 wild moth, increasing the probability of a female moth mating with a sterile male. This target is often achieved and the programme is generally successful, however there are some challenges regarding this programme. The mass rearing environment, artificial diet, handling methods and irradiation have an impact on sterile insect quality as environmental differences between the rearing facility and field, influences the insect phenotype and competitiveness. This is evident as wild male moths can theoretically actively fly at a temperature of 12°C and laboratory-reared sterilized moths, due to the radiation treatment, appear unable to fly below 20°C. As a consequence, sterile males are out-competed by wild males during the cooler months of the year. This is detrimental to the SIT programme as FCM do not undergo diapause, meaning they are active during winter and will still reproduce. Therefore, to maximize the effect of the SIT programme, it is vital to increase the flight ability of mass reared sterile males at lower temperatures. Various studies have shown that by adding cryoprotectants to the basic laboratory diets increases the cold tolerance of certain insects and thus may allow them to be mobile at lower temperatures, however it imperative that any chemical used to augment the commercial diet of the insect has no negative effects on the insect physiology and development. To investigate this detail for FCM, five generations of FCM were reared on diets augmented with various known insect cryoprotectants. These augmented FCM were subsequently used in experiments designed to determine firstly, if the cryoprotectants had a positive result on the cold tolerance of the FCM, and secondly, if they had any adverse effects on other physiological aspects such as duration of development. Laboratory trials indicated that the flight ability of male FCM was improved when larvae were reared on diets augmented with trehalose and cholesterol (with an average of 40 % of cholesterol and trehalose augmented males that flew at 15 °C where 0 % of the control flew). Results obtained during the field trials support the laboratory results as there was a significant increase in the number of trehalose augmented moths caught in the field during March and July (winter). Results also showed potential for cholesterol to be used as an additive. Other important findings show that both cholesterol and trehalose have no negative impacts on developmental rate, pupal size, and egg production and viability. Trehalose was found to increase the pupal mass of male and female FCM, as well as the number of eggs laid per female. Cholesterol was found to increase developmental rate and the number of eggs laid. The main findings of this study were that diet additives could improve the massrearing of FCM for SIT and the competitiveness of the males, especially at lower temperatures. However, the additives were expensive and cost could well be a constraint to the wide scale implementation of the new technology.
- Full Text:
- Authors: Daniel, Claire Ashleigh
- Date: 2017
- Subjects: Cryptophlebia leucotreta -- South Africa , Cryptophlebia leucotreta -- Reproduction -- Effect of temperature on , Cryptophlebia leucotreta -- Biological control -- South Africa , Citrus -- Diseases and pests -- Biological control -- South Africa , Insect pests -- Biological control -- South Africa , Insecticides , Citrus fruit industry -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/5271 , vital:20803
- Description: The false codling moth (FCM), Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is a major pest of citrus and other important crops in Sub-Saharan Africa. The introduction of a sterile insect technique (SIT) programme for FCM in South Africa has proven to be very effective in the control of FCM. The objective was to flood citrus orchards with large numbers of sterile males resulting in a ratio of at least 10 sterile to 1 wild moth, increasing the probability of a female moth mating with a sterile male. This target is often achieved and the programme is generally successful, however there are some challenges regarding this programme. The mass rearing environment, artificial diet, handling methods and irradiation have an impact on sterile insect quality as environmental differences between the rearing facility and field, influences the insect phenotype and competitiveness. This is evident as wild male moths can theoretically actively fly at a temperature of 12°C and laboratory-reared sterilized moths, due to the radiation treatment, appear unable to fly below 20°C. As a consequence, sterile males are out-competed by wild males during the cooler months of the year. This is detrimental to the SIT programme as FCM do not undergo diapause, meaning they are active during winter and will still reproduce. Therefore, to maximize the effect of the SIT programme, it is vital to increase the flight ability of mass reared sterile males at lower temperatures. Various studies have shown that by adding cryoprotectants to the basic laboratory diets increases the cold tolerance of certain insects and thus may allow them to be mobile at lower temperatures, however it imperative that any chemical used to augment the commercial diet of the insect has no negative effects on the insect physiology and development. To investigate this detail for FCM, five generations of FCM were reared on diets augmented with various known insect cryoprotectants. These augmented FCM were subsequently used in experiments designed to determine firstly, if the cryoprotectants had a positive result on the cold tolerance of the FCM, and secondly, if they had any adverse effects on other physiological aspects such as duration of development. Laboratory trials indicated that the flight ability of male FCM was improved when larvae were reared on diets augmented with trehalose and cholesterol (with an average of 40 % of cholesterol and trehalose augmented males that flew at 15 °C where 0 % of the control flew). Results obtained during the field trials support the laboratory results as there was a significant increase in the number of trehalose augmented moths caught in the field during March and July (winter). Results also showed potential for cholesterol to be used as an additive. Other important findings show that both cholesterol and trehalose have no negative impacts on developmental rate, pupal size, and egg production and viability. Trehalose was found to increase the pupal mass of male and female FCM, as well as the number of eggs laid per female. Cholesterol was found to increase developmental rate and the number of eggs laid. The main findings of this study were that diet additives could improve the massrearing of FCM for SIT and the competitiveness of the males, especially at lower temperatures. However, the additives were expensive and cost could well be a constraint to the wide scale implementation of the new technology.
- Full Text:
In silico analysis of plasmodium falciparum Hsp70-x for potential binding sites and hits
- Authors: Amusengeri, Arnold
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/59136 , vital:27435
- Description: Restricted access-thesis embargoed for 1 year - release date April 2019
- Full Text:
- Authors: Amusengeri, Arnold
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/59136 , vital:27435
- Description: Restricted access-thesis embargoed for 1 year - release date April 2019
- Full Text:
Integrating Climate Change Adaptation (CCA) and Disaster Risk Reduction (DRR) for greater local level resilience: lessons from a multi-stakeholder think-tank
- Pereira, Taryn, Shackleton, Sheona E, Donkor, Felix Kwabena
- Authors: Pereira, Taryn , Shackleton, Sheona E , Donkor, Felix Kwabena
- Date: 2017
- Subjects: Climatic changes -- South Africa , Climatic changes -- South Africa -- Eastern Cape -- South Africa
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/62027 , vital:28097
- Description: The last few years have seen one of the most severe droughts in recent times in the southern African region, and news headlines are increasingly full of warnings about heavy storms, fires and floods. There is no doubt that extreme hydro-meteorological events, and their multiple and potentially disastrous impacts, are at the forefront of the public consciousness at the present time and are one of the key concerns regarding the impacts of climate change in the region. While the links between extreme climate events, disaster risk reduction (DRR - see Box 1) and climate change adaptation (CCA - see Box 2) are recognised in the South African Climate Change White Paper, this is not the case for the whole region. Furthermore, even if there is national recognition of the need to synergise these two spheres of endeavour, this does not always trickle down to effective policy, planning and implementation at the local level.
- Full Text:
- Authors: Pereira, Taryn , Shackleton, Sheona E , Donkor, Felix Kwabena
- Date: 2017
- Subjects: Climatic changes -- South Africa , Climatic changes -- South Africa -- Eastern Cape -- South Africa
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/62027 , vital:28097
- Description: The last few years have seen one of the most severe droughts in recent times in the southern African region, and news headlines are increasingly full of warnings about heavy storms, fires and floods. There is no doubt that extreme hydro-meteorological events, and their multiple and potentially disastrous impacts, are at the forefront of the public consciousness at the present time and are one of the key concerns regarding the impacts of climate change in the region. While the links between extreme climate events, disaster risk reduction (DRR - see Box 1) and climate change adaptation (CCA - see Box 2) are recognised in the South African Climate Change White Paper, this is not the case for the whole region. Furthermore, even if there is national recognition of the need to synergise these two spheres of endeavour, this does not always trickle down to effective policy, planning and implementation at the local level.
- Full Text:
Interactions between two biological control agents released on Pereskia aculeata Miller (Cactaceae), in South Africa
- Authors: Mnqeta, Zezethu
- Date: 2017
- Subjects: Pereskia aculeata -- Biological control , Cactus -- Biological control -- South Africa , Alien plants -- Biological control -- South Africa , Flea beetles -- South Africa , Coreidae -- South Africa , Insects as biological pest control agents -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/7949 , vital:21327
- Description: Pereskia aculeata Miller (Cactaceae) is an alien invasive plant introduced into South Africa from Brazil, which has negative impacts on native biodiversity in South Africa. Phenrica guerini Bechyne (Chrysomelidae) and Catorhintha schaffneri Brailovsky & Garcia (Coreidae) are two biological control agents released against P. aculeata in South Africa. Phenrica guerini was first released against P. aculeata, in 1991, followed by C. schaffneri in 2014. The overall aim of this study was to improve the biological control programme against P. aculeata in order to decrease its density to a level where it does not threaten the native biodiversity of South Africa. The first part of this study evaluated the efficacy of P. guerini on P. aculeata at Port Alfred (Eastern Cape) to better understand the role of P. guerini in the biological control of P. aculeata. An insecticide exclusion experiment was conducted over 100 days. Plots with P. guerini had a mean of 187 (SE ± 62) fewer leaves/m2 than plots without P. guerini. The agent reduced percentage cover in plots with P. guerini, with a mean of 19.42% (SE ± 3.15) lower cover than plots without P. guerini. Although P. guerini had an impact on P. aculeata at Port Alfred previous studies have indicated that a reduction to below 50% cover is required for native biodiversity to recover and the agent only reduced cover to 62% at Port Alfred. Phenrica guerini has therefore not reduced percentage cover sufficiently to completely control the weed. The data collected from Port Alfred was compared to the performance of the agent nationwide. Although P. guerini was found at far more sites than previously recorded, there were very few sites with comparable levels of damage to Port Alfred. This evidence suggests that P. guerini is not sufficiently damaging to reduce P. aculeata to acceptable levels and other biological control agents should be considered.Interactions between two biological control agents can have complex and unexpected impacts for a biological control programme. The second part of this study was to investigate interactions between C. schaffneri and P. guerini under laboratory conditions to test whether the two agents, individually or jointly, enhanced or reduced their impact on P. aculeata. Potted P. aculeata plants were exposed to one of four treatments: control (no agents), P. guerini only, C. schaffneri only and both species in combination. Four stocking densities, ranging from 2 to 12 insects per plant were used. Catorhintha schaffneri alone at high densities was more damaging than all other treatments with a significantly greater reduction in the mean number of leaves, 11.7 (SE ± 1.29), and shoot lengths, 2.17cm (SE ± O. 75). Even at lower density treatments, the combination of the two agents was not significantly more damaging than C. schaffneri alone and C. schaffneri was always more damaging than P. guerini alone. Mortality of P. guerini was significantly higher than C. schaffneri at the highest stocking density when in combination. Phenrica guerini contributes towards the biological control of P. aculeata at some sites in South Africa but not enough to completely control the weed. The antagonistic interaction between P. guerini and C. schaffneri suggests that these agents should not be released together because this would impact negatively on the overall biocontrol programme against P. aculeata. Catorhintha schaffneri should be released at sites were P. guerini is not present and evaluations of the success of this agent in the field should be conducted. Extrapolation of laboratory-based studies into the field is often challenging so mass-rearing of P. guerini should continue until there is convincing proof that C. schaffneri alone is more effective than P. guerini in the field.
- Full Text:
- Authors: Mnqeta, Zezethu
- Date: 2017
- Subjects: Pereskia aculeata -- Biological control , Cactus -- Biological control -- South Africa , Alien plants -- Biological control -- South Africa , Flea beetles -- South Africa , Coreidae -- South Africa , Insects as biological pest control agents -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/7949 , vital:21327
- Description: Pereskia aculeata Miller (Cactaceae) is an alien invasive plant introduced into South Africa from Brazil, which has negative impacts on native biodiversity in South Africa. Phenrica guerini Bechyne (Chrysomelidae) and Catorhintha schaffneri Brailovsky & Garcia (Coreidae) are two biological control agents released against P. aculeata in South Africa. Phenrica guerini was first released against P. aculeata, in 1991, followed by C. schaffneri in 2014. The overall aim of this study was to improve the biological control programme against P. aculeata in order to decrease its density to a level where it does not threaten the native biodiversity of South Africa. The first part of this study evaluated the efficacy of P. guerini on P. aculeata at Port Alfred (Eastern Cape) to better understand the role of P. guerini in the biological control of P. aculeata. An insecticide exclusion experiment was conducted over 100 days. Plots with P. guerini had a mean of 187 (SE ± 62) fewer leaves/m2 than plots without P. guerini. The agent reduced percentage cover in plots with P. guerini, with a mean of 19.42% (SE ± 3.15) lower cover than plots without P. guerini. Although P. guerini had an impact on P. aculeata at Port Alfred previous studies have indicated that a reduction to below 50% cover is required for native biodiversity to recover and the agent only reduced cover to 62% at Port Alfred. Phenrica guerini has therefore not reduced percentage cover sufficiently to completely control the weed. The data collected from Port Alfred was compared to the performance of the agent nationwide. Although P. guerini was found at far more sites than previously recorded, there were very few sites with comparable levels of damage to Port Alfred. This evidence suggests that P. guerini is not sufficiently damaging to reduce P. aculeata to acceptable levels and other biological control agents should be considered.Interactions between two biological control agents can have complex and unexpected impacts for a biological control programme. The second part of this study was to investigate interactions between C. schaffneri and P. guerini under laboratory conditions to test whether the two agents, individually or jointly, enhanced or reduced their impact on P. aculeata. Potted P. aculeata plants were exposed to one of four treatments: control (no agents), P. guerini only, C. schaffneri only and both species in combination. Four stocking densities, ranging from 2 to 12 insects per plant were used. Catorhintha schaffneri alone at high densities was more damaging than all other treatments with a significantly greater reduction in the mean number of leaves, 11.7 (SE ± 1.29), and shoot lengths, 2.17cm (SE ± O. 75). Even at lower density treatments, the combination of the two agents was not significantly more damaging than C. schaffneri alone and C. schaffneri was always more damaging than P. guerini alone. Mortality of P. guerini was significantly higher than C. schaffneri at the highest stocking density when in combination. Phenrica guerini contributes towards the biological control of P. aculeata at some sites in South Africa but not enough to completely control the weed. The antagonistic interaction between P. guerini and C. schaffneri suggests that these agents should not be released together because this would impact negatively on the overall biocontrol programme against P. aculeata. Catorhintha schaffneri should be released at sites were P. guerini is not present and evaluations of the success of this agent in the field should be conducted. Extrapolation of laboratory-based studies into the field is often challenging so mass-rearing of P. guerini should continue until there is convincing proof that C. schaffneri alone is more effective than P. guerini in the field.
- Full Text:
Investigating herbivory and plant origin on tall-statured grasses in South Africa
- Authors: Canavan, Kim
- Date: 2017
- Subjects: Insects as biological pest control agents -- South Africa , Arundo donax , Giant reed -- South Africa , Giant reed -- Biological control -- South Africa , Phragmites australis , Phragmites mauritianus , Phragmites , Tetramesa romana , Biological invasions -- South Africa , Wasps -- Host plants , Wasps -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/6147 , vital:21051
- Description: South African riparian zones have been heavily degraded through anthropogenic activities such as dam construction and extraction of water for irrigation, which has resulted in a loss of ecosystem services and functioning. A consequence of such disturbances to riparian areas is in their susceptibility to invasive alien species (IAS). One such IAS is the giant reed, Arundo donax L. (Poaceae), introduced to South Africa in the 1700s largely for erosion control. Arundo donax has since greatly expanded in the country and is now one of the most abundant IAS. Arundo donax has been found to displace native vegetation and in South Africa this will most likely lead to the displacement of the native tall-statured grasses, Phragmites australis (Cav.) Trin. ex Steud. and Phragmites mauritianus Kunth. This study aimed to enhance our understanding of the tall-statured grasses A. donax, P. australis and P. mauritianus to better manage them in riparian areas. For A. donax, biological control is seen as the most viable option to control stands in the long-term. However, before such a programme is put in place, it is important to first collect baseline data that can be used to guide the direction of the biological control project in South Africa. For the Phragmites spp., despite being a dominant vegetative type in riparian areas, very little is known about their status in South Africa. Furthermore, there have been increasing reports of both Phragmites species having an expansion of their range and abundance. In North America, there has been a similar trend of reed expansion and through molecular work it was determined that a cryptic invasion has occurred with the introduction of an invasive non-native haplotype from Europe. It is therefore unknown if Phragmites spp. populations are expanding due to anthropogenic activities or due to a cryptic invasion. To address these shortfalls in knowledge the study investigated the tall-statured grasses in two parts; firstly, molecular techniques are used to explore the plant origin and genetic diversity of A. donax, P. australis and P. mauritianus and secondly using the Enemy Release Hypothesis as a framework, herbivore assemblages for each reed was determined across their distribution in South Africa. Molecular-techniques determined that both P. australis and P. mauritianus had only one haplotype - known as haplotype K and haplotype V respectively, across their distribution. For P. australis, haplotype K shares a close connection with populations from a Mediterranean lineage and this was further confirmed with a shared grass-waxy band. The direction and timing of genetic exchange between the two regions could not be ascertained and thus still remains unknown. Microsatellite analysis determined that both Phragmites spp. had a high genetic diversity compared to worldwide lineages. With no evidence of any cryptic invasions of haplotypes from other regions, both Phragmites spp. populations are likely to be native to South Africa. For A. donax all populations across South Africa were determined to be haplotype M1; a cosmopolitan haplotype that has an ancient native range in Afghanistan and Pakistan (Indus Valley). Populations were found to have no genetic diversity and thus can be considered one clone. A pre-introductory survey determined a list of herbivores associated with each tall- statured grass. For A. donax, a total of seven herbivores were found. Of these, one herbivore, a galling wasp, Tetramesa romana Walker (Hymenoptera: Eurytomidae) was found to be highly abundant and widely distributed in South Africa. Tetramesa romana is already a biological control agent in North America and thus is likely exerting some pressure on A. donax populations in South Africa. For both Phragmites spp. a total of ten herbivores were found, although having higher species richness compared to A. donax, when compared to other regions, these native species have a relatively low species richness. Providing baseline data on plant origin, genetic diversity and herbivory on A. donax, P. australis and P. mauritianus has provided important information on managing these species in riparian ecosystems in South Africa. For the Phragmites spp. with no evidence of any cryptic invasions, it is recommended that reed stands continue to be managed as native species. Phragmites spp. are important dominant vegetative species and thus should be protected; however, if reed stands become expansive, control methods can be put in place to focus on managing spread and abundance. For A. donax, this study was able to provide pivotal information in guiding the biological control programme. By determining the ancient lineage of South African populations, research can be focused in this area to find potential biological control agents. Lastly, the pre-introductory survey determined that a biological control agent, T. romana was already established with an unknown introduction and also highlighted potential plant parts that should be targeted. In particular, no rhizome feeding herbivores were found in South Africa and therefore this highlights an important niche that should be explored in biological control agents.
- Full Text:
- Authors: Canavan, Kim
- Date: 2017
- Subjects: Insects as biological pest control agents -- South Africa , Arundo donax , Giant reed -- South Africa , Giant reed -- Biological control -- South Africa , Phragmites australis , Phragmites mauritianus , Phragmites , Tetramesa romana , Biological invasions -- South Africa , Wasps -- Host plants , Wasps -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/6147 , vital:21051
- Description: South African riparian zones have been heavily degraded through anthropogenic activities such as dam construction and extraction of water for irrigation, which has resulted in a loss of ecosystem services and functioning. A consequence of such disturbances to riparian areas is in their susceptibility to invasive alien species (IAS). One such IAS is the giant reed, Arundo donax L. (Poaceae), introduced to South Africa in the 1700s largely for erosion control. Arundo donax has since greatly expanded in the country and is now one of the most abundant IAS. Arundo donax has been found to displace native vegetation and in South Africa this will most likely lead to the displacement of the native tall-statured grasses, Phragmites australis (Cav.) Trin. ex Steud. and Phragmites mauritianus Kunth. This study aimed to enhance our understanding of the tall-statured grasses A. donax, P. australis and P. mauritianus to better manage them in riparian areas. For A. donax, biological control is seen as the most viable option to control stands in the long-term. However, before such a programme is put in place, it is important to first collect baseline data that can be used to guide the direction of the biological control project in South Africa. For the Phragmites spp., despite being a dominant vegetative type in riparian areas, very little is known about their status in South Africa. Furthermore, there have been increasing reports of both Phragmites species having an expansion of their range and abundance. In North America, there has been a similar trend of reed expansion and through molecular work it was determined that a cryptic invasion has occurred with the introduction of an invasive non-native haplotype from Europe. It is therefore unknown if Phragmites spp. populations are expanding due to anthropogenic activities or due to a cryptic invasion. To address these shortfalls in knowledge the study investigated the tall-statured grasses in two parts; firstly, molecular techniques are used to explore the plant origin and genetic diversity of A. donax, P. australis and P. mauritianus and secondly using the Enemy Release Hypothesis as a framework, herbivore assemblages for each reed was determined across their distribution in South Africa. Molecular-techniques determined that both P. australis and P. mauritianus had only one haplotype - known as haplotype K and haplotype V respectively, across their distribution. For P. australis, haplotype K shares a close connection with populations from a Mediterranean lineage and this was further confirmed with a shared grass-waxy band. The direction and timing of genetic exchange between the two regions could not be ascertained and thus still remains unknown. Microsatellite analysis determined that both Phragmites spp. had a high genetic diversity compared to worldwide lineages. With no evidence of any cryptic invasions of haplotypes from other regions, both Phragmites spp. populations are likely to be native to South Africa. For A. donax all populations across South Africa were determined to be haplotype M1; a cosmopolitan haplotype that has an ancient native range in Afghanistan and Pakistan (Indus Valley). Populations were found to have no genetic diversity and thus can be considered one clone. A pre-introductory survey determined a list of herbivores associated with each tall- statured grass. For A. donax, a total of seven herbivores were found. Of these, one herbivore, a galling wasp, Tetramesa romana Walker (Hymenoptera: Eurytomidae) was found to be highly abundant and widely distributed in South Africa. Tetramesa romana is already a biological control agent in North America and thus is likely exerting some pressure on A. donax populations in South Africa. For both Phragmites spp. a total of ten herbivores were found, although having higher species richness compared to A. donax, when compared to other regions, these native species have a relatively low species richness. Providing baseline data on plant origin, genetic diversity and herbivory on A. donax, P. australis and P. mauritianus has provided important information on managing these species in riparian ecosystems in South Africa. For the Phragmites spp. with no evidence of any cryptic invasions, it is recommended that reed stands continue to be managed as native species. Phragmites spp. are important dominant vegetative species and thus should be protected; however, if reed stands become expansive, control methods can be put in place to focus on managing spread and abundance. For A. donax, this study was able to provide pivotal information in guiding the biological control programme. By determining the ancient lineage of South African populations, research can be focused in this area to find potential biological control agents. Lastly, the pre-introductory survey determined that a biological control agent, T. romana was already established with an unknown introduction and also highlighted potential plant parts that should be targeted. In particular, no rhizome feeding herbivores were found in South Africa and therefore this highlights an important niche that should be explored in biological control agents.
- Full Text:
Investigating the expression of three small open reading frames encoded on Helicoverpa armigera stunt virus RNA 1
- Authors: De Bruyn, Mart-Mari
- Date: 2017
- Subjects: Helicoverpa armigera , RNA viruses , Insects Viruses , Proteins
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/59168 , vital:27448
- Description: The Helicoverpa armigera stunt virus (HaSV), belonging to the Family Alphatetraviridae (Genus: Omegatetravirus), is a non-enveloped insect virus encapsidating a bi-partite, positive-sense single-stranded RNA genome. RNA1 encodes the replicase, as well as three small open reading frames (ORFs) arranged in tandem, and overlapping with the 3’ end of the replicase ORF. These ORFs, designated p11, p15 and p8, encode putative proteins of unknown function. The p11 and p15 ORFs are conserved in the genome of the related Omegatetravirus, Dendrolimus punctatus tetravirus. In HaSV, the stop codon of p11 is followed immediately by the start of p15, whereas the stop of p15 and start of p8 are separated by a glycine intercodon. Furthermore, only p11 is known to have a recognizable Kozak sequence. The aim of this study was to determine the expression and function of these three small proteins in the HaSV infectious lifecycle. The authenticity of the viral cDNA sequence, encoding the three small ORFs, was validated by sequencing multiple cDNA clones of the relevant region in viral RNA (vRNA), purified from infectious HaSV particles. The sequence of all three ORFs was conserved in seven cDNA clones, while point mutations were observed in each of two remaining cDNA clones, suggesting that the ORFs were conserved in infectious virus. Polyclonal antisera were raised against a p11 peptide, and a recombinant p15-p8 fusion protein (p23) expressed and purified from Escherichia coli. The affinity of the anti-p23 antiserum was confirmed by western blot analysis, while that of the anti-p11 antiserum was confirmed using immunofluorescence microscopy, as attempted expression of recombinant p11 in E. coli appeared to be toxic. The antisera were used to detect expression of the small proteins in HaSV-infected H. armigera larvae by western blot analysis. A band migrating at approximately 34 kDa was detected by both antisera in infected larvae, absent in uninfected larvae, suggesting the expression of a p11-p15-p8 polyprotein. Protein bands of 11 kDa and 8 kDa were also detected by the anti-p11 and anti-p23 antisera, respectively. Bioinformatic analysis revealed that the polyprotein would be produced by a novel type of stop codon read-through, however the mechanism required for individual expression could not be definitively determined. The mechanism by which these ORFs are translated was further investigated by expressing p11-p15, tagged with FLAG and enhanced green flourescent protein (EGFP) at its amino- and carboxyl-termini respectively (FLAG-p11-p15-EGFP), in Spodoptera frugiperda (Sf9) cells detected by flourescence microscopy. Punctate structures were observed throughout the cytoplasm that were also detected with antiFLAG, anti-p11 and anti-p23 antisera, complementing results obtained in previous studies. Since p15 does not exhibit a strong recognizable Kozak like p11, the dependency of p15 expression on that of p11 was investigated by mutating this construct such that p15 occurred in a +1 frame to p11. Both EGFP and anti-p23 fluorescence was detected with the same cytoplasmic distribution as the unmutated construct, whereas nothing was detected by anti-FLAG and anti-p11. Preliminary results therefore suggested p15 may also be expressed as a discrete protein, independent of p11. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2018
- Full Text:
- Authors: De Bruyn, Mart-Mari
- Date: 2017
- Subjects: Helicoverpa armigera , RNA viruses , Insects Viruses , Proteins
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/59168 , vital:27448
- Description: The Helicoverpa armigera stunt virus (HaSV), belonging to the Family Alphatetraviridae (Genus: Omegatetravirus), is a non-enveloped insect virus encapsidating a bi-partite, positive-sense single-stranded RNA genome. RNA1 encodes the replicase, as well as three small open reading frames (ORFs) arranged in tandem, and overlapping with the 3’ end of the replicase ORF. These ORFs, designated p11, p15 and p8, encode putative proteins of unknown function. The p11 and p15 ORFs are conserved in the genome of the related Omegatetravirus, Dendrolimus punctatus tetravirus. In HaSV, the stop codon of p11 is followed immediately by the start of p15, whereas the stop of p15 and start of p8 are separated by a glycine intercodon. Furthermore, only p11 is known to have a recognizable Kozak sequence. The aim of this study was to determine the expression and function of these three small proteins in the HaSV infectious lifecycle. The authenticity of the viral cDNA sequence, encoding the three small ORFs, was validated by sequencing multiple cDNA clones of the relevant region in viral RNA (vRNA), purified from infectious HaSV particles. The sequence of all three ORFs was conserved in seven cDNA clones, while point mutations were observed in each of two remaining cDNA clones, suggesting that the ORFs were conserved in infectious virus. Polyclonal antisera were raised against a p11 peptide, and a recombinant p15-p8 fusion protein (p23) expressed and purified from Escherichia coli. The affinity of the anti-p23 antiserum was confirmed by western blot analysis, while that of the anti-p11 antiserum was confirmed using immunofluorescence microscopy, as attempted expression of recombinant p11 in E. coli appeared to be toxic. The antisera were used to detect expression of the small proteins in HaSV-infected H. armigera larvae by western blot analysis. A band migrating at approximately 34 kDa was detected by both antisera in infected larvae, absent in uninfected larvae, suggesting the expression of a p11-p15-p8 polyprotein. Protein bands of 11 kDa and 8 kDa were also detected by the anti-p11 and anti-p23 antisera, respectively. Bioinformatic analysis revealed that the polyprotein would be produced by a novel type of stop codon read-through, however the mechanism required for individual expression could not be definitively determined. The mechanism by which these ORFs are translated was further investigated by expressing p11-p15, tagged with FLAG and enhanced green flourescent protein (EGFP) at its amino- and carboxyl-termini respectively (FLAG-p11-p15-EGFP), in Spodoptera frugiperda (Sf9) cells detected by flourescence microscopy. Punctate structures were observed throughout the cytoplasm that were also detected with antiFLAG, anti-p11 and anti-p23 antisera, complementing results obtained in previous studies. Since p15 does not exhibit a strong recognizable Kozak like p11, the dependency of p15 expression on that of p11 was investigated by mutating this construct such that p15 occurred in a +1 frame to p11. Both EGFP and anti-p23 fluorescence was detected with the same cytoplasmic distribution as the unmutated construct, whereas nothing was detected by anti-FLAG and anti-p11. Preliminary results therefore suggested p15 may also be expressed as a discrete protein, independent of p11. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2018
- Full Text:
Investigation of the potency of topical corticosteroids using the vasoconstrictor assay
- Authors: Zvidzayi, Kudzayi Michael
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/65279 , vital:28717
- Description: Expected release date-May 2019
- Full Text:
- Authors: Zvidzayi, Kudzayi Michael
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/65279 , vital:28717
- Description: Expected release date-May 2019
- Full Text:
Ionospheric disturbances during magnetic storms at SANAE
- Authors: Hiyadutuje, Alicreance
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/54956 , vital:26639
- Description: The coronal mass ejections (CMEs) and solar flares associated with extreme solar activity may strike the Earth's magnetosphere and give rise to geomagnetic storms. During geomagnetic storms, the polar plasma dynamics may influence the middle and low-latitude ionosphere via travelling ionospheric disturbances (TIDs). These are wave-like electron density disturbances caused by atmospheric gravity waves propagating in the ionosphere. TIDs focus and defocus SuperDARN signals producing a characteristic pattern of ground backscattered power (Samson et al., 1989). Geomagnetic storms may cause a decrease of total electron content (TEC), i.e. a negative storm effect, or/and an increase of TEC, i.e. a positive storm effect. The aim of this project was to investigate the ionospheric response to strong storms (Dst < -100 nT) between 2011 and 2015, using TEC and scintillation measurements derived from GPS receivers as well as SuperDARN power, Doppler velocity and convection maps. In this study the ionosphere's response to geomagnetic storms is determined by the magnitude and time of occurrence of the geomagnetic storm. The ionospheric TEC results of this study show that most of the storm effects observed were a combination of both negative and positive per storm per station (77.8%), and only 8.9% and 13.3% of effects on TEC were negative and positive respectively. The highest number of storm effects occurred in autumn (36.4%), while 31.6%, 28.4% and 3.6% occurred in winter, spring and summer respectively. During the storms studied, 71.4% had phase scintillation in the range of 0.7 - 1 radians, and only 14.3% of the storms had amplitude scintillations near 0.4. The storms studied at SANAE station generated TIDs with periods of less than an hour and amplitudes in the range 0.2 - 5 TECU. These TIDs were found to originate from the high-velocity plasma flows, some of which are visible in SuperDARN convection maps. Early studies concluded that likely sources of these disturbances correspond to ionospheric current surges (Bristow et al., 1994) in the dayside auroral zone (Huang et al., 1998).
- Full Text:
- Authors: Hiyadutuje, Alicreance
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/54956 , vital:26639
- Description: The coronal mass ejections (CMEs) and solar flares associated with extreme solar activity may strike the Earth's magnetosphere and give rise to geomagnetic storms. During geomagnetic storms, the polar plasma dynamics may influence the middle and low-latitude ionosphere via travelling ionospheric disturbances (TIDs). These are wave-like electron density disturbances caused by atmospheric gravity waves propagating in the ionosphere. TIDs focus and defocus SuperDARN signals producing a characteristic pattern of ground backscattered power (Samson et al., 1989). Geomagnetic storms may cause a decrease of total electron content (TEC), i.e. a negative storm effect, or/and an increase of TEC, i.e. a positive storm effect. The aim of this project was to investigate the ionospheric response to strong storms (Dst < -100 nT) between 2011 and 2015, using TEC and scintillation measurements derived from GPS receivers as well as SuperDARN power, Doppler velocity and convection maps. In this study the ionosphere's response to geomagnetic storms is determined by the magnitude and time of occurrence of the geomagnetic storm. The ionospheric TEC results of this study show that most of the storm effects observed were a combination of both negative and positive per storm per station (77.8%), and only 8.9% and 13.3% of effects on TEC were negative and positive respectively. The highest number of storm effects occurred in autumn (36.4%), while 31.6%, 28.4% and 3.6% occurred in winter, spring and summer respectively. During the storms studied, 71.4% had phase scintillation in the range of 0.7 - 1 radians, and only 14.3% of the storms had amplitude scintillations near 0.4. The storms studied at SANAE station generated TIDs with periods of less than an hour and amplitudes in the range 0.2 - 5 TECU. These TIDs were found to originate from the high-velocity plasma flows, some of which are visible in SuperDARN convection maps. Early studies concluded that likely sources of these disturbances correspond to ionospheric current surges (Bristow et al., 1994) in the dayside auroral zone (Huang et al., 1998).
- Full Text:
Land, Church, Forced Removals and Community on Klipfontein Farm in the District of Alexandria, Eastern Cape c. 1872 - 1979
- Authors: Bezuidenhout, GJW
- Date: 2017
- Subjects: Janse van Rensburg family , Klipfontein Farm (Alexandria, South Africa) , Alexandria (South Africa) -- History , Colored people (South Africa) -- History , Colored people (South Africa) -- Religion , Colored people (South Africa) -- Relocation , Black people -- Relocation -- South Africa -- Eastern Cape , Family farms -- South Africa -- Eastern Cape , Church history -- South Africa -- Eastern Cape , Land tenure -- Law and legilstion -- South Africa , Land reform -- Law and legislation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/161315 , vital:40615
- Description: This thesis is a case study of how church, land and dispossession of land has influenced identity formation of a coloured community in the Eastern Province, namely the Klipfontein community. Coloured history in the Eastern Province has largely been neglected. This study attempts to rectify such a lack of in-depth enquiry as it may lead to misinterpretations that may influence contemporary politics and identity formation. Through research based on primary sources, it is evident that the social landscape of Klipfontein Farm and the relationships between that community and surrounding black African and white communities have largely been shaped by the stipulations contained in the joint will of the community’s ancestors: Dirk and Sarah Janse van Rensburg. The land devolved into a trust and has been administered by trustees since the death of the first spouse in 1877. By keeping the land in a trust, it enabled the descendants to continue to live on the farm in perpetuity, without the risk of being forced off the land via financial restraints or racially-based legislation. But the usufructuaries could also never fully utilise Klipfontein as an agricultural concern due to a combination of a lack of equipment and skill, and the provisions of the will. These complications inevitably led to inter-familial disputes and tension. Before 1939 there had already been three court cases dealing with the interpretations of the Will. In that same year the Supreme Court ordered that tracts of the land, including a part of Boesmansriviermond village, be sold in order to pay off arrear rates and taxes. Although the responsibility for these sales lay with the trustees, the community has been suspicious of the usufructuaries ever since. A key element of the Klipfontein identity is their religion. The church legitimises their right to the farm - against those who wish to take that right away. Their claim to occupation is couched in scriptural discourse, viewing Klipfontein as 'their Garden of Eden' that God gave to the stamvader, Dirk Janse van Rensburg. This seemed to have been partially successful for the Klipfontein community in staving off harassment by authorities. It also caused friction between the community and the black African residents. Some usufructuaries and family members felt that such right was exclusively given to the coloured community and so they became increasingly annoyed by the black Africans who settled there. Other usufructuaries did not share this feeling. They allowed evicted black African farm labourers to settle on certain portions of Klipfontein until the late 1970s. The black African population rapidly increased due to misinformation and evictions from neighbouring farms. This only further exacerbated the inter-familial conflict between usufructuaries, flaring tensions between the black Africans and their reluctant hosts as well as animosity from the white community towards Klipfontein. In 1979, after a series of court cases, a decision was made to remove all the African settlers by force and relocate most of them to the ‘homeland’ of Ciskei. The rest, who were of ‘working-age’ were left behind in a ‘temporary emergency camp’ on the outskirts of Kenton-on-Sea. The effects of these removals still impact the relationships between the different racial groups in the area to this day.
- Full Text:
- Authors: Bezuidenhout, GJW
- Date: 2017
- Subjects: Janse van Rensburg family , Klipfontein Farm (Alexandria, South Africa) , Alexandria (South Africa) -- History , Colored people (South Africa) -- History , Colored people (South Africa) -- Religion , Colored people (South Africa) -- Relocation , Black people -- Relocation -- South Africa -- Eastern Cape , Family farms -- South Africa -- Eastern Cape , Church history -- South Africa -- Eastern Cape , Land tenure -- Law and legilstion -- South Africa , Land reform -- Law and legislation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/161315 , vital:40615
- Description: This thesis is a case study of how church, land and dispossession of land has influenced identity formation of a coloured community in the Eastern Province, namely the Klipfontein community. Coloured history in the Eastern Province has largely been neglected. This study attempts to rectify such a lack of in-depth enquiry as it may lead to misinterpretations that may influence contemporary politics and identity formation. Through research based on primary sources, it is evident that the social landscape of Klipfontein Farm and the relationships between that community and surrounding black African and white communities have largely been shaped by the stipulations contained in the joint will of the community’s ancestors: Dirk and Sarah Janse van Rensburg. The land devolved into a trust and has been administered by trustees since the death of the first spouse in 1877. By keeping the land in a trust, it enabled the descendants to continue to live on the farm in perpetuity, without the risk of being forced off the land via financial restraints or racially-based legislation. But the usufructuaries could also never fully utilise Klipfontein as an agricultural concern due to a combination of a lack of equipment and skill, and the provisions of the will. These complications inevitably led to inter-familial disputes and tension. Before 1939 there had already been three court cases dealing with the interpretations of the Will. In that same year the Supreme Court ordered that tracts of the land, including a part of Boesmansriviermond village, be sold in order to pay off arrear rates and taxes. Although the responsibility for these sales lay with the trustees, the community has been suspicious of the usufructuaries ever since. A key element of the Klipfontein identity is their religion. The church legitimises their right to the farm - against those who wish to take that right away. Their claim to occupation is couched in scriptural discourse, viewing Klipfontein as 'their Garden of Eden' that God gave to the stamvader, Dirk Janse van Rensburg. This seemed to have been partially successful for the Klipfontein community in staving off harassment by authorities. It also caused friction between the community and the black African residents. Some usufructuaries and family members felt that such right was exclusively given to the coloured community and so they became increasingly annoyed by the black Africans who settled there. Other usufructuaries did not share this feeling. They allowed evicted black African farm labourers to settle on certain portions of Klipfontein until the late 1970s. The black African population rapidly increased due to misinformation and evictions from neighbouring farms. This only further exacerbated the inter-familial conflict between usufructuaries, flaring tensions between the black Africans and their reluctant hosts as well as animosity from the white community towards Klipfontein. In 1979, after a series of court cases, a decision was made to remove all the African settlers by force and relocate most of them to the ‘homeland’ of Ciskei. The rest, who were of ‘working-age’ were left behind in a ‘temporary emergency camp’ on the outskirts of Kenton-on-Sea. The effects of these removals still impact the relationships between the different racial groups in the area to this day.
- Full Text:
Language and access in the public healthcare system in South Africa with a particular focus on primary public health facilities in Grahamstown and Cofimvaba in the Eastern Cape
- Authors: Mhlauli, Nonceba
- Date: 2017
- Subjects: Health literacy -- South Africa -- Eastern Cape , Patient education -- South Africa -- Eastern Cape , Communication in medicine -- South Africa -- Eastern Cape , Health literacy -- Social aspects -- South Africa -- Eastern Cape , Poor -- Medical care -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/56692 , vital:26817
- Description: The right to language and the right to healthcare services are human rights which are enshrined in the Constitution of the Republic of South Africa. Section 6 (5) of the Constitution and Section 1.3 (b) and (e) of the Eastern Cape Provincial Language Policy provide protection against unfair discrimination on the grounds of language; while sections 30 and 31 (1) of the Constitution refer to people’s rights in terms of cultural, religious and linguistic participation. Section 27 (a) states that ‘everyone has the right to access to healthcare services’. In accordance with the Constitution, in 2011 the National Department of Health passed a Policy on Language Services. This policy aims to facilitate equitable access to government services and information, as well as respect for language rights as spelled out in the Constitution. The Policy on Language Services further aims to promote multilingualism in the National Department of Health and to allow people to access information in a language of their choice, understand important messages and the language necessary for informed and participatory decision making (Department of Health 2011:1). Given the above policy and Constitutional provisions as far as policy commitment is concerned, the crucial issue remains the implementation of such policy to ensure that the right to access to health and language are realised. The study provides an analysis of the Policy on Language Services 2011 as it relates to language rights and the delivery of health services, focusing on the roll out and implementation process and the public awareness of the policy. This study primarily focuses on the role language plays in accessing public healthcare in primary healthcare facilities in the Grahamstown and Cofimvaba. The study looked at communication between patient and healthcare providers and whether healthcare services were provided in the language of the patient or the language the patient knows best. This study further assessed indications of patients’ comprehension of information such as medical instructions on packaged medicine, comprehension of posters, pamphlets and health education sessions in order to fully participate in the process of their health status. The data of this research was collected from healthcare providers and patients in primary healthcare facilities in Grahamstown and Cofimvaba in the Eastern Cape. The research methods used was in-depth interviews, non-participant observations as well as content analysis such as sign/direction posts, medical labels and information boards. These methods were used to determine whether language plays a role in accessing quality healthcare services in these facilities. The research found that the lack of implementation of language and health policy resulted in the perpetuation of language barriers in the healthcare sector. The study therefore argues that adequate healthcare can only be provided if and when healthcare providers and patients are able to communicate with each other in the language they know best or feel most comfortable in. Thus meaning the implementation of the current Constitutional and policy provisions is crucial to language and access to healthcare services.
- Full Text:
- Authors: Mhlauli, Nonceba
- Date: 2017
- Subjects: Health literacy -- South Africa -- Eastern Cape , Patient education -- South Africa -- Eastern Cape , Communication in medicine -- South Africa -- Eastern Cape , Health literacy -- Social aspects -- South Africa -- Eastern Cape , Poor -- Medical care -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/56692 , vital:26817
- Description: The right to language and the right to healthcare services are human rights which are enshrined in the Constitution of the Republic of South Africa. Section 6 (5) of the Constitution and Section 1.3 (b) and (e) of the Eastern Cape Provincial Language Policy provide protection against unfair discrimination on the grounds of language; while sections 30 and 31 (1) of the Constitution refer to people’s rights in terms of cultural, religious and linguistic participation. Section 27 (a) states that ‘everyone has the right to access to healthcare services’. In accordance with the Constitution, in 2011 the National Department of Health passed a Policy on Language Services. This policy aims to facilitate equitable access to government services and information, as well as respect for language rights as spelled out in the Constitution. The Policy on Language Services further aims to promote multilingualism in the National Department of Health and to allow people to access information in a language of their choice, understand important messages and the language necessary for informed and participatory decision making (Department of Health 2011:1). Given the above policy and Constitutional provisions as far as policy commitment is concerned, the crucial issue remains the implementation of such policy to ensure that the right to access to health and language are realised. The study provides an analysis of the Policy on Language Services 2011 as it relates to language rights and the delivery of health services, focusing on the roll out and implementation process and the public awareness of the policy. This study primarily focuses on the role language plays in accessing public healthcare in primary healthcare facilities in the Grahamstown and Cofimvaba. The study looked at communication between patient and healthcare providers and whether healthcare services were provided in the language of the patient or the language the patient knows best. This study further assessed indications of patients’ comprehension of information such as medical instructions on packaged medicine, comprehension of posters, pamphlets and health education sessions in order to fully participate in the process of their health status. The data of this research was collected from healthcare providers and patients in primary healthcare facilities in Grahamstown and Cofimvaba in the Eastern Cape. The research methods used was in-depth interviews, non-participant observations as well as content analysis such as sign/direction posts, medical labels and information boards. These methods were used to determine whether language plays a role in accessing quality healthcare services in these facilities. The research found that the lack of implementation of language and health policy resulted in the perpetuation of language barriers in the healthcare sector. The study therefore argues that adequate healthcare can only be provided if and when healthcare providers and patients are able to communicate with each other in the language they know best or feel most comfortable in. Thus meaning the implementation of the current Constitutional and policy provisions is crucial to language and access to healthcare services.
- Full Text:
Malawi’s foreign policy decision-making: the 2012 Malawi-Tanzania boundary dispute
- Kaunda, Mapopa Charles Martin Sazamleke
- Authors: Kaunda, Mapopa Charles Martin Sazamleke
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/59225 , vital:27484
- Description: Expected release date-April 2019
- Full Text:
- Authors: Kaunda, Mapopa Charles Martin Sazamleke
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/59225 , vital:27484
- Description: Expected release date-April 2019
- Full Text:
Microbial water quality monitoring of raw and treated water sources in Harare and the effect of gender in disaster management due to water related disasters
- Authors: Chirenda, Tatenda Grace
- Date: 2017
- Subjects: Drinking water Microbiology Zimbabwe Harare , Heterotrophic bacteria Zimbabwe Harare , Emergency management Zimbabwe Harare , Disasters Social aspects Zimbabwe Harare , Water quality management Zimbabwe Harare , Public health Zimbabwe Harare , Sex role Zimbabwe Harare
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/59156 , vital:27444
- Description: Background - Microbial water quality monitoring is essential to the provision of potable water for domestic use. Unsafe water sources increase the risk of waterborne diseases. There is a need to raise awareness of legislature that supports management of water related disasters. Gender, education, health, and economic vulnerability contribute to the success of disaster management. Aim - This study aimed to investigate the microbial water quality of treated water in the Harare area. The study also researched the microbial water quality monitoring practices in Zimbabwe and how these contribute to the management of water borne diseases. The impact of gender, marriage, education, and disease in disaster management practices in Zimbabwe and South Africa was analysed. Method - Literature review was conducted on microbial water quality monitoring practices in Zimbabwe and legislature that supports disaster management. Practices of disaster management in Zimbabwe, and South Africa were investigated and compared. The perspective of the Harare community on the quality of their potable water was investigated through the use of a questionnaire and water quality testing was conducted using hydrogen sulphide test and R2A based heterotrophic plate count. Raw water supplying Manyame River and tap water in Harare households were assessed for microbial quality. Results and Discussion - Raw water sources were found to be contaminated by faecal matter. Household water sources had no faecal contamination, but tested positive for heterotrophic bacteria. The CFU/ml quantities obtained ranged from 1- 452 CFU/ml for all samples. The WHO guidelines for domestic water sources recommend that domestic water should have no coliforms/100 ml sample. Disaster management protocols were available in disaster prone areas such as the Matabeleland South Province. No guidelines were in place for monitoring microbial water quality as a disaster prevention method. Conclusion - The current state of treated water supplied by the Morton Jaffray Treatment Plant was found to be suitable for domestic use, but not sufficient to meet the Harare population’s needs. The need to push for legislature supporting microbial water quality monitoring was recognised. Initiating public / private partnerships in water distribution and water quality monitoring in Zimbabwe was encouraged.
- Full Text:
- Authors: Chirenda, Tatenda Grace
- Date: 2017
- Subjects: Drinking water Microbiology Zimbabwe Harare , Heterotrophic bacteria Zimbabwe Harare , Emergency management Zimbabwe Harare , Disasters Social aspects Zimbabwe Harare , Water quality management Zimbabwe Harare , Public health Zimbabwe Harare , Sex role Zimbabwe Harare
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/59156 , vital:27444
- Description: Background - Microbial water quality monitoring is essential to the provision of potable water for domestic use. Unsafe water sources increase the risk of waterborne diseases. There is a need to raise awareness of legislature that supports management of water related disasters. Gender, education, health, and economic vulnerability contribute to the success of disaster management. Aim - This study aimed to investigate the microbial water quality of treated water in the Harare area. The study also researched the microbial water quality monitoring practices in Zimbabwe and how these contribute to the management of water borne diseases. The impact of gender, marriage, education, and disease in disaster management practices in Zimbabwe and South Africa was analysed. Method - Literature review was conducted on microbial water quality monitoring practices in Zimbabwe and legislature that supports disaster management. Practices of disaster management in Zimbabwe, and South Africa were investigated and compared. The perspective of the Harare community on the quality of their potable water was investigated through the use of a questionnaire and water quality testing was conducted using hydrogen sulphide test and R2A based heterotrophic plate count. Raw water supplying Manyame River and tap water in Harare households were assessed for microbial quality. Results and Discussion - Raw water sources were found to be contaminated by faecal matter. Household water sources had no faecal contamination, but tested positive for heterotrophic bacteria. The CFU/ml quantities obtained ranged from 1- 452 CFU/ml for all samples. The WHO guidelines for domestic water sources recommend that domestic water should have no coliforms/100 ml sample. Disaster management protocols were available in disaster prone areas such as the Matabeleland South Province. No guidelines were in place for monitoring microbial water quality as a disaster prevention method. Conclusion - The current state of treated water supplied by the Morton Jaffray Treatment Plant was found to be suitable for domestic use, but not sufficient to meet the Harare population’s needs. The need to push for legislature supporting microbial water quality monitoring was recognised. Initiating public / private partnerships in water distribution and water quality monitoring in Zimbabwe was encouraged.
- Full Text: