Responses to the linked stressors of climate change and HIV/AIDS amongst vulnerable rural households in the Eastern Cape, South Africa
- Authors: Clarke, Caryn Lee
- Date: 2013
- Subjects: Climatic changes -- South Africa -- Eastern Cape Climatic changes -- Health aspects -- South Africa -- Eastern Cape Climatic changes -- Economic aspects -- South Africa -- Eastern Cape HIV infections -- Economic aspects -- South Africa -- Eastern Cape AIDS (Disease) -- Economic aspects -- South Africa -- Eastern Cape HIV infections -- Social aspects -- South Africa -- Eastern Cape AIDS (Disease) -- Social aspects -- South Africa -- Eastern Cape Poverty -- Social aspects -- South Africa -- Eastern Cape Income -- South Africa -- Eastern Cape Human capital -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4732 , http://hdl.handle.net/10962/d1003818
- Description: Climate change and the HIV/AIDS epidemic are two of the most critical long-term global challenges, especially for Africa and even more so Southern Africa. There is great concern that the poor will be unable to adapt to the impacts of climate variability and change while HIV/AIDS will exacerbate the impacts of such stressors and deepen the insecurities of many communities already affected by this disease. Studies that consider the interlinked effects of climate change and HIV/AIDS along with other multiple stressors are increasingly needed. This study, located in two rural communities in the Eastern Cape Province of South Africa, namely Lesseyton and Willowvale, assessed the responses of vulnerable households to the linked shocks and stressors of climate change and HIV/AIDS. This involved assessing, through household surveys, life history interviews and Participatory Learning and Action (PLA), the way in which multiple stressors interacted and affected vulnerable households, the way in which these households responded to and coped with such shocks and stressors, and the barriers which prevented them from coping and adapting effectively. Unemployment emerged as the dominant stress amongst households. The lack of development and having too few opportunities for employment has limited vulnerable households from being able to invest in assets, such as education or farming equipment. This, in combination with the impacts of increased food and water insecurity from recent drought, has created an extremely vulnerable environment for these households. They rely largely on two important safety-nets, namely social capital and the use of natural and cultivated resources; however the latter has been limited due to the impacts of water scarcity and an inability to farm. It was evident that there was little planned long-term adaptation amongst households and from government. Maladaptive short-term coping strategies, such numerous household members depending on one social grant and transactional sex, were too often relied upon, and although they may have helped relieve the stress of shocks momentarily, they did not provide for the long-term well-being of individuals and households. Poor communication and capacity between the different levels of government and between the government (especially at the local level) and the two rural communities has created an environment full of uncertainty and lacking in advocacy. Local government needs increased human, informational, and financial capacity and a clear delegation of responsibilities amongst the different departments in order for the two communities to benefit from the implementation of support strategies. There is also a great need for educational programmes and capacity development within the two rural communities, particularly based on improved coping and longer-term adaptation strategies in response to climate change in order for households to better prepare themselves for the future.
- Full Text:
- Date Issued: 2013
- Authors: Clarke, Caryn Lee
- Date: 2013
- Subjects: Climatic changes -- South Africa -- Eastern Cape Climatic changes -- Health aspects -- South Africa -- Eastern Cape Climatic changes -- Economic aspects -- South Africa -- Eastern Cape HIV infections -- Economic aspects -- South Africa -- Eastern Cape AIDS (Disease) -- Economic aspects -- South Africa -- Eastern Cape HIV infections -- Social aspects -- South Africa -- Eastern Cape AIDS (Disease) -- Social aspects -- South Africa -- Eastern Cape Poverty -- Social aspects -- South Africa -- Eastern Cape Income -- South Africa -- Eastern Cape Human capital -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4732 , http://hdl.handle.net/10962/d1003818
- Description: Climate change and the HIV/AIDS epidemic are two of the most critical long-term global challenges, especially for Africa and even more so Southern Africa. There is great concern that the poor will be unable to adapt to the impacts of climate variability and change while HIV/AIDS will exacerbate the impacts of such stressors and deepen the insecurities of many communities already affected by this disease. Studies that consider the interlinked effects of climate change and HIV/AIDS along with other multiple stressors are increasingly needed. This study, located in two rural communities in the Eastern Cape Province of South Africa, namely Lesseyton and Willowvale, assessed the responses of vulnerable households to the linked shocks and stressors of climate change and HIV/AIDS. This involved assessing, through household surveys, life history interviews and Participatory Learning and Action (PLA), the way in which multiple stressors interacted and affected vulnerable households, the way in which these households responded to and coped with such shocks and stressors, and the barriers which prevented them from coping and adapting effectively. Unemployment emerged as the dominant stress amongst households. The lack of development and having too few opportunities for employment has limited vulnerable households from being able to invest in assets, such as education or farming equipment. This, in combination with the impacts of increased food and water insecurity from recent drought, has created an extremely vulnerable environment for these households. They rely largely on two important safety-nets, namely social capital and the use of natural and cultivated resources; however the latter has been limited due to the impacts of water scarcity and an inability to farm. It was evident that there was little planned long-term adaptation amongst households and from government. Maladaptive short-term coping strategies, such numerous household members depending on one social grant and transactional sex, were too often relied upon, and although they may have helped relieve the stress of shocks momentarily, they did not provide for the long-term well-being of individuals and households. Poor communication and capacity between the different levels of government and between the government (especially at the local level) and the two rural communities has created an environment full of uncertainty and lacking in advocacy. Local government needs increased human, informational, and financial capacity and a clear delegation of responsibilities amongst the different departments in order for the two communities to benefit from the implementation of support strategies. There is also a great need for educational programmes and capacity development within the two rural communities, particularly based on improved coping and longer-term adaptation strategies in response to climate change in order for households to better prepare themselves for the future.
- Full Text:
- Date Issued: 2013
The development and assessment of a fixed dose combination tablet of Ranitidine and Metronidazole
- Authors: King'ori, Loti David
- Date: 2011 , 2011-04-07
- Subjects: Ulcers -- Treatment , Ranitidine -- Evaluation , Metronidazole -- Evaluation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3858 , http://hdl.handle.net/10962/d1013359
- Description: The oral route of drug administration is convenient since it is acceptable to most patients and the manufacturing processes used to produce tablets and capsules are relatively simple when compared to those used to manufacture other types of dosage forms. Metronidazole (MTZ) and Ranitidine (RTD) have been used in combination, as part of triple therapy for the treatment of ulcers. However the use of large numbers of tablets and long duration of therapy makes adherence to drug treatment challenging for patients. Therefore the formulation of a fixed dose combination (FDC) of MTZ and RTD may improve patient adherence to therapy and consequently may reduce morbidity and mortality due to ulcers. A stability indicating HPLC method for the simultaneous analysis of MTZ and RTD was developed and validated according to the International Conference on Harmonization (ICH) guidelines. The method was sensitive, selective, precise, accurate and linear.Preformulation studies were performed on the active pharmaceutical ingredients (API) alone and in combination with potential excipients. Differential scanning calorimetry (DSC) studies revealed a potential interaction between MTZ and RTD, however the interaction was not apparent following IR analysis of the same samples. DSC analyses of the API in combination with potential excipients revealed that the compounds were compatible with most materials with the exception of a binary mixture of RTD and Dibasic calcium phosphate (DCP) that exhibited a potential interaction. Thermal gravimetric analysis (TGA) of MTZ and RTD revealed that both compounds exhibited thermal stability. The Carrs Index (CI) and Hausner Ratio (HR) values of MTZ and RTD indicated that both compounds exhibited poor flow and compressibility properties, whereas the CI and HR values for (Microcrystalline cellulose) MCC and DCP indicated better flowability and compressibility characteristics.Direct compression and wet granulation processes were assessed to identify a suitable method of manufacture of FDC tablets of MTZ and RTD. The blends were evaluated using bulk and tapped density and the resultant tablets were evaluated for weight uniformity, crushing strength, tensile strength and disintegration time. The wet granulation method of manufacture produced tablets that showed acceptable pharmacotechnical properties: this approach was therefore used as the method of manufacture of FDC tablets of MTZ and RTD. Tablet formulations comprised of API, viz. MTZ and RTD and different compositions of MCC, DCP, Sodium starch glycolate (SSG) and Croscarmellose sodium (CCS), were manufactured in order to screen for an appropriate diluent and disintegrant composition for use in response surface studies. Assays of tablet content and in vitro drug release were undertaken using the validated HPLC method. Tablets in which MCC and CCS were used appeared to produce better assay and dissolution results as compared to those manufactured using DCP and SSG. Consequently a formulation comprised of MCC and CCS was selected and used in studies in which the effect(s) of level two formulation and composition changes as described in the Scale and Post Approval Changes for Immediate Release (SUPAC-IR) Guidelines on tablet disintegration and in vitro release were assessed. A Box-Behnken statistical design was used for the investigation of the effect of input factors, viz. CCS, (Polyvinyl pyrollidone K30) PVP-K30 and magnesium stearate on measured responses, viz. disintegration time and percent drug release in 10 minutes (Q10). CCS appeared to have an inverse linear relationship on disintegration time and a linear relationship with the Q10 for MTZ and RTD, whereas PVP-K30 and magnesium stearate appeared to have an antagonistic effect on the measured responses. Furthermore CCS and magnesium stearate exhibited an interaction that had an agonistic effect on the Q10 value for RTD. A numerical optimization approach was used to predict a formulation composition that would produce tablets that exhibited a disintegration time and Q10 values for MTZ and RTD that fell within the constraints set in our laboratory. The resultant model was found to be accurate and had a percent prediction error of < 5% for all measured response variables.FDC tablets of MTZ and RTD have been successfully produced. The disintegration of the tablet and dissolution of the API were within compendial specifications and the tablets are of suitable quality and have the potential to be further investigated to reduce the pill burden in the treatment of ulcers.
- Full Text:
- Date Issued: 2011
- Authors: King'ori, Loti David
- Date: 2011 , 2011-04-07
- Subjects: Ulcers -- Treatment , Ranitidine -- Evaluation , Metronidazole -- Evaluation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3858 , http://hdl.handle.net/10962/d1013359
- Description: The oral route of drug administration is convenient since it is acceptable to most patients and the manufacturing processes used to produce tablets and capsules are relatively simple when compared to those used to manufacture other types of dosage forms. Metronidazole (MTZ) and Ranitidine (RTD) have been used in combination, as part of triple therapy for the treatment of ulcers. However the use of large numbers of tablets and long duration of therapy makes adherence to drug treatment challenging for patients. Therefore the formulation of a fixed dose combination (FDC) of MTZ and RTD may improve patient adherence to therapy and consequently may reduce morbidity and mortality due to ulcers. A stability indicating HPLC method for the simultaneous analysis of MTZ and RTD was developed and validated according to the International Conference on Harmonization (ICH) guidelines. The method was sensitive, selective, precise, accurate and linear.Preformulation studies were performed on the active pharmaceutical ingredients (API) alone and in combination with potential excipients. Differential scanning calorimetry (DSC) studies revealed a potential interaction between MTZ and RTD, however the interaction was not apparent following IR analysis of the same samples. DSC analyses of the API in combination with potential excipients revealed that the compounds were compatible with most materials with the exception of a binary mixture of RTD and Dibasic calcium phosphate (DCP) that exhibited a potential interaction. Thermal gravimetric analysis (TGA) of MTZ and RTD revealed that both compounds exhibited thermal stability. The Carrs Index (CI) and Hausner Ratio (HR) values of MTZ and RTD indicated that both compounds exhibited poor flow and compressibility properties, whereas the CI and HR values for (Microcrystalline cellulose) MCC and DCP indicated better flowability and compressibility characteristics.Direct compression and wet granulation processes were assessed to identify a suitable method of manufacture of FDC tablets of MTZ and RTD. The blends were evaluated using bulk and tapped density and the resultant tablets were evaluated for weight uniformity, crushing strength, tensile strength and disintegration time. The wet granulation method of manufacture produced tablets that showed acceptable pharmacotechnical properties: this approach was therefore used as the method of manufacture of FDC tablets of MTZ and RTD. Tablet formulations comprised of API, viz. MTZ and RTD and different compositions of MCC, DCP, Sodium starch glycolate (SSG) and Croscarmellose sodium (CCS), were manufactured in order to screen for an appropriate diluent and disintegrant composition for use in response surface studies. Assays of tablet content and in vitro drug release were undertaken using the validated HPLC method. Tablets in which MCC and CCS were used appeared to produce better assay and dissolution results as compared to those manufactured using DCP and SSG. Consequently a formulation comprised of MCC and CCS was selected and used in studies in which the effect(s) of level two formulation and composition changes as described in the Scale and Post Approval Changes for Immediate Release (SUPAC-IR) Guidelines on tablet disintegration and in vitro release were assessed. A Box-Behnken statistical design was used for the investigation of the effect of input factors, viz. CCS, (Polyvinyl pyrollidone K30) PVP-K30 and magnesium stearate on measured responses, viz. disintegration time and percent drug release in 10 minutes (Q10). CCS appeared to have an inverse linear relationship on disintegration time and a linear relationship with the Q10 for MTZ and RTD, whereas PVP-K30 and magnesium stearate appeared to have an antagonistic effect on the measured responses. Furthermore CCS and magnesium stearate exhibited an interaction that had an agonistic effect on the Q10 value for RTD. A numerical optimization approach was used to predict a formulation composition that would produce tablets that exhibited a disintegration time and Q10 values for MTZ and RTD that fell within the constraints set in our laboratory. The resultant model was found to be accurate and had a percent prediction error of < 5% for all measured response variables.FDC tablets of MTZ and RTD have been successfully produced. The disintegration of the tablet and dissolution of the API were within compendial specifications and the tablets are of suitable quality and have the potential to be further investigated to reduce the pill burden in the treatment of ulcers.
- Full Text:
- Date Issued: 2011
The amphibolite at Chibuluma Mine Zambia
- Authors: Thomson, Iain Dennis
- Date: 1969
- Subjects: Amphibolite -- Zambia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5066 , http://hdl.handle.net/10962/d1013391
- Description: Chibuluma Mine is situated on the southern flank of the Nkana-Chambishi basin in the central section of the Zambian Copperbelt. The amphibolite at Chibuluma Mine occurs exclusively in the Upper Roan Group sediments overlying the economically important Lower Roan Group. The amphibolite occurs in lenticular, sill-like bodies ranging in thickness from less than 10 feet to over 1,000 feet. It is concluded that these sill-like bodies are intrusive sills of basic magma. The largest sill is a multiple intrusion with two phases, both of which exhibit chilled margins. The younger phase was intruded into the older along a plane approximately 50 feet above its basal contact. Grainsize, specific gravity, and micrometric data indicate that each phase of the intrusion has undergone gravitational differentiation during crystallisation. Variations in the relative amounts of amphibole and feldspar distinguish between a lower melanocratic amphibolite, an upper mesotype amphibolite, and a zone of coarse-grained pegmatitic amphibolite schlieren. The amphibolite consists mainly of hornblende, labradorite, albite, and scapolite, with accessory biotite, chlorite, epidote, clinozoisite, sphene, apatite, quartz, micropegmatite, and calcite. Clouding of the basic plagioclase and zoning in amphibole, plagioclase, and scapolite are features of petrological significance. The opaque minerals in the amphibolites and the adjacent sediments are magnetite, ilmenite, pyrite, chalcopyrite, pyrrhotite, cubanite, valleriite, and pentlandite. Intergrowths of these suggest that their temperatures of formation were probably in excess of 450°C. The chemical data show a close resemblance between the amphibolite and a tholeiitic magma-type although minor spilitic characteristics are also evident. The chemical data also confirm the mineralogical evidence of fractionation and gravitational differentiation. The trend in differentiation followed in the development of the pegmatitic and mesotype amphibolite is very similar to the trends followed by other basic intrusions. The main metamorphic affect accompanying the intrusion of the amphibolite is the soda metasomatism evident in both sediments and intrusions. Some evidence exists to suggest that the amphibolites were emplaced before or during the early stages of the Lufilian orogeny when sediments were essentially horizontal.
- Full Text:
- Date Issued: 1969
- Authors: Thomson, Iain Dennis
- Date: 1969
- Subjects: Amphibolite -- Zambia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5066 , http://hdl.handle.net/10962/d1013391
- Description: Chibuluma Mine is situated on the southern flank of the Nkana-Chambishi basin in the central section of the Zambian Copperbelt. The amphibolite at Chibuluma Mine occurs exclusively in the Upper Roan Group sediments overlying the economically important Lower Roan Group. The amphibolite occurs in lenticular, sill-like bodies ranging in thickness from less than 10 feet to over 1,000 feet. It is concluded that these sill-like bodies are intrusive sills of basic magma. The largest sill is a multiple intrusion with two phases, both of which exhibit chilled margins. The younger phase was intruded into the older along a plane approximately 50 feet above its basal contact. Grainsize, specific gravity, and micrometric data indicate that each phase of the intrusion has undergone gravitational differentiation during crystallisation. Variations in the relative amounts of amphibole and feldspar distinguish between a lower melanocratic amphibolite, an upper mesotype amphibolite, and a zone of coarse-grained pegmatitic amphibolite schlieren. The amphibolite consists mainly of hornblende, labradorite, albite, and scapolite, with accessory biotite, chlorite, epidote, clinozoisite, sphene, apatite, quartz, micropegmatite, and calcite. Clouding of the basic plagioclase and zoning in amphibole, plagioclase, and scapolite are features of petrological significance. The opaque minerals in the amphibolites and the adjacent sediments are magnetite, ilmenite, pyrite, chalcopyrite, pyrrhotite, cubanite, valleriite, and pentlandite. Intergrowths of these suggest that their temperatures of formation were probably in excess of 450°C. The chemical data show a close resemblance between the amphibolite and a tholeiitic magma-type although minor spilitic characteristics are also evident. The chemical data also confirm the mineralogical evidence of fractionation and gravitational differentiation. The trend in differentiation followed in the development of the pegmatitic and mesotype amphibolite is very similar to the trends followed by other basic intrusions. The main metamorphic affect accompanying the intrusion of the amphibolite is the soda metasomatism evident in both sediments and intrusions. Some evidence exists to suggest that the amphibolites were emplaced before or during the early stages of the Lufilian orogeny when sediments were essentially horizontal.
- Full Text:
- Date Issued: 1969
- «
- ‹
- 1
- ›
- »