Biochemical evaluation of Tulbaghia violacea harv.rhizomes in diet induced hypercholestrolemic rats
- Olorunnisola, Olubukola Sinbad
- Authors: Olorunnisola, Olubukola Sinbad
- Date: 2012
- Subjects: Violaceae , Anticoagulants (Medicine) , Antineoplastic agents , Rats , Hypercholesteremia , Cardiovascular agents , Medicinal plants
- Language: English
- Type: Thesis , Doctoral , PhD (Biochemistry)
- Identifier: vital:11273 , http://hdl.handle.net/10353/d1006900 , Violaceae , Anticoagulants (Medicine) , Antineoplastic agents , Rats , Hypercholesteremia , Cardiovascular agents , Medicinal plants
- Description: Discovery of cheap, nontoxic and readily available antiatherosclerotic drugs is an extraordinary challenge in this modern world. Atherosclerosis and cardiovascular diseases have been predicted to be the leading cause of death by the year 2030. Hence, this thesis was designed to search for plant (s) with anti-atherogenic properties, investigate its possible side effects and extrapolate its likely mechanism(s) of action. An ethnobotanical survey was employed in identification of locally important plants used for the management and treatment of cardiovascular diseases and its predisposing factors in Nkonkobe Municipality, Eastern Cape in South Africa. Information on the names of plants, their parts used and methods of preparation was collected through a questionnaire which was administered to herbalists, traditional healers and rural dwellers. The most frequently used plant (Rhizomes of Tulbaghia violacea Harv.) was investigated for toxicity using brine shrimp lethality (in vitro) and in vivo toxicity test (acute and subchronic) on rats to determine safety dosage. The in vitro antioxidant and free radical scavenging activity of the plant was investigated using models such as 1,1-diphenyl-2- picrylhydrazyl (DPPH), superoxide anions, hydrogen peroxide (H2O2), nitric oxide (NO), 2,2’- azinobis [3-ethylbenzothiazoline-6-sulfonic acid] diammonium salt (ABTS), lipid peroxidation inhibition and the ferric reducing agent. Phytochemical content and the effect of oral administration of fresh methanolic extract rhizomes of Tulbaghia violacea (250, 500 mg/kg. bwt/day) on Lipid peroxidation (TBARS), serum and tissue antioxidant enzymes in normal, hypercholesterolemic and diet induced atherogenic rats were also assessed. More so, the potential of the extract (250 and 500 mg/kg. bwt) to protect against atherogenic diet (4 percentage cholesterol 1 pecentage cholic acid and 0.5 percentage thiouracil) induced fatty streaks formation, dyslipidemia, oxidative stress and endothelial dysfunction was also investigated. Ethnobotanical study revealed that 19 plant species are used for the treatment of heart related diseases in the Municipality. 53 percentage of the plants mentioned were used for the management of chest pain, 47 percentage for high blood pressure, 42 percent for heart disease, 16 percentage for stroke and 11 percentage for the treatment of hypercholesterolemia. Tulbaghia violacea was repeatedly mentioned as the plant species used for the treatment of high blood pressure and predisposing factors in the study area. The brine shrimp cytotoxicity test revealed that fresh, dried methanolic extracts and essential oil of the T. violacea exhibited a high degree of cytotoxic activity with IC50 values of 18.18 (fresh) and 19.24 (dried) μg/ml. An IC50 value of 12. 59 μg/ml was obtained for the essential oil of the plant. The low cytotoxicity values obtained, suggested that rhizome of T. violacea may serve as a potential source of antimicrobial and anticancer agents. In vivo acute study of single oral administration of 5g/kg dose does not produce mortality or significant behavioral changes during 14 days observation. In the sub-chronic study, the extract (250, 500 mg/kg/bwt/ day) administered for a period of 28 days showed no mortality or morbidity. The weekly body and organ weight of the rats showed no significant differences between the control and the rats treated with the extract. The extract at all doses does not show any effect on of biomarkers of liver or renal damage. However, a significant decrease in the activity of ƔGT was observed in the extract treated groups. Hematological evaluation revealed that oral administration of fresh methanolic extracts of rhizomes of T. violacea does not cause anaemia or leucocytosis in the animals. Furthermore, histopathology results of the internal organs revealed no detectable inflammation. These results demonstrated that the rhizome extract of T. violacea was potentially safe for consumption orally even in chronic concentration. In vitro antioxidant evaluation showed that the essential oil, fresh and dried methanolic extracts exhibited potent antioxidant activities in a concentration dependent manner. Phytochemical investigation reveals that the fresh and the dry extract of RTV are rich in flavonoid, flavonol, phenols, tannin and proanthocyanidin, while the essential oil contained dimethy disulfide, dimethyl trisulfide, (methyl methylthio) methyl, 2,4-dithiapentane (11.35 percent) and (methylthio) acetic acid, 2- (methylthio) ethanol, 3-(methylthio) - and propanenitrile (7.20 percent). The fresh extract had higher radicals scavenging activity than the essential oil or dried extract, with 50 percentage inhibition of DPPH, hydrogen peroxide and lipid peroxidation at a concentration of 35.0 ± 0.12, 19.3 ± 0.11 and 17.9 ± 0.15 μg/ml respectively. Oral administration of methanolic extract of RTV in 125, 250 and 500 mg/kg to female Wistar rats significantly inhibited reduction of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). The extracts also inhibited (p< 0.05) lipid peroxidation in normal, high cholesterol and diet induced atherosclerosis fed rats in a dose dependant manner. Also the extract (250 and 500 mg/kg/bwt/day) caused a significant (p<0.05) improvement in body weight of treated animals compared with untreated hypercholesterolemia control rats. The extracts also protected significantly (p<0.05) against atherogenic diet induced liver damage or fatty streaks formation in the aorta as revealed by histological examination. The anti-cholesterolemia and anti-atherosclerotic activities of the extract compared favorably well with standard drugs Gemfibrozil and Atorvastatin respectively. Conclusively, rhizomes of T. violacea possess significant anti-atherogenic activity and its mechanism of action(s) may be due to its antioxidant and anti-hypercholesterolemia properties. The results of this study also suggested that rhizome of T. violacea is relatively safe for human consumption and it may be used as an alternative to garlic.
- Full Text:
- Date Issued: 2012
- Authors: Olorunnisola, Olubukola Sinbad
- Date: 2012
- Subjects: Violaceae , Anticoagulants (Medicine) , Antineoplastic agents , Rats , Hypercholesteremia , Cardiovascular agents , Medicinal plants
- Language: English
- Type: Thesis , Doctoral , PhD (Biochemistry)
- Identifier: vital:11273 , http://hdl.handle.net/10353/d1006900 , Violaceae , Anticoagulants (Medicine) , Antineoplastic agents , Rats , Hypercholesteremia , Cardiovascular agents , Medicinal plants
- Description: Discovery of cheap, nontoxic and readily available antiatherosclerotic drugs is an extraordinary challenge in this modern world. Atherosclerosis and cardiovascular diseases have been predicted to be the leading cause of death by the year 2030. Hence, this thesis was designed to search for plant (s) with anti-atherogenic properties, investigate its possible side effects and extrapolate its likely mechanism(s) of action. An ethnobotanical survey was employed in identification of locally important plants used for the management and treatment of cardiovascular diseases and its predisposing factors in Nkonkobe Municipality, Eastern Cape in South Africa. Information on the names of plants, their parts used and methods of preparation was collected through a questionnaire which was administered to herbalists, traditional healers and rural dwellers. The most frequently used plant (Rhizomes of Tulbaghia violacea Harv.) was investigated for toxicity using brine shrimp lethality (in vitro) and in vivo toxicity test (acute and subchronic) on rats to determine safety dosage. The in vitro antioxidant and free radical scavenging activity of the plant was investigated using models such as 1,1-diphenyl-2- picrylhydrazyl (DPPH), superoxide anions, hydrogen peroxide (H2O2), nitric oxide (NO), 2,2’- azinobis [3-ethylbenzothiazoline-6-sulfonic acid] diammonium salt (ABTS), lipid peroxidation inhibition and the ferric reducing agent. Phytochemical content and the effect of oral administration of fresh methanolic extract rhizomes of Tulbaghia violacea (250, 500 mg/kg. bwt/day) on Lipid peroxidation (TBARS), serum and tissue antioxidant enzymes in normal, hypercholesterolemic and diet induced atherogenic rats were also assessed. More so, the potential of the extract (250 and 500 mg/kg. bwt) to protect against atherogenic diet (4 percentage cholesterol 1 pecentage cholic acid and 0.5 percentage thiouracil) induced fatty streaks formation, dyslipidemia, oxidative stress and endothelial dysfunction was also investigated. Ethnobotanical study revealed that 19 plant species are used for the treatment of heart related diseases in the Municipality. 53 percentage of the plants mentioned were used for the management of chest pain, 47 percentage for high blood pressure, 42 percent for heart disease, 16 percentage for stroke and 11 percentage for the treatment of hypercholesterolemia. Tulbaghia violacea was repeatedly mentioned as the plant species used for the treatment of high blood pressure and predisposing factors in the study area. The brine shrimp cytotoxicity test revealed that fresh, dried methanolic extracts and essential oil of the T. violacea exhibited a high degree of cytotoxic activity with IC50 values of 18.18 (fresh) and 19.24 (dried) μg/ml. An IC50 value of 12. 59 μg/ml was obtained for the essential oil of the plant. The low cytotoxicity values obtained, suggested that rhizome of T. violacea may serve as a potential source of antimicrobial and anticancer agents. In vivo acute study of single oral administration of 5g/kg dose does not produce mortality or significant behavioral changes during 14 days observation. In the sub-chronic study, the extract (250, 500 mg/kg/bwt/ day) administered for a period of 28 days showed no mortality or morbidity. The weekly body and organ weight of the rats showed no significant differences between the control and the rats treated with the extract. The extract at all doses does not show any effect on of biomarkers of liver or renal damage. However, a significant decrease in the activity of ƔGT was observed in the extract treated groups. Hematological evaluation revealed that oral administration of fresh methanolic extracts of rhizomes of T. violacea does not cause anaemia or leucocytosis in the animals. Furthermore, histopathology results of the internal organs revealed no detectable inflammation. These results demonstrated that the rhizome extract of T. violacea was potentially safe for consumption orally even in chronic concentration. In vitro antioxidant evaluation showed that the essential oil, fresh and dried methanolic extracts exhibited potent antioxidant activities in a concentration dependent manner. Phytochemical investigation reveals that the fresh and the dry extract of RTV are rich in flavonoid, flavonol, phenols, tannin and proanthocyanidin, while the essential oil contained dimethy disulfide, dimethyl trisulfide, (methyl methylthio) methyl, 2,4-dithiapentane (11.35 percent) and (methylthio) acetic acid, 2- (methylthio) ethanol, 3-(methylthio) - and propanenitrile (7.20 percent). The fresh extract had higher radicals scavenging activity than the essential oil or dried extract, with 50 percentage inhibition of DPPH, hydrogen peroxide and lipid peroxidation at a concentration of 35.0 ± 0.12, 19.3 ± 0.11 and 17.9 ± 0.15 μg/ml respectively. Oral administration of methanolic extract of RTV in 125, 250 and 500 mg/kg to female Wistar rats significantly inhibited reduction of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). The extracts also inhibited (p< 0.05) lipid peroxidation in normal, high cholesterol and diet induced atherosclerosis fed rats in a dose dependant manner. Also the extract (250 and 500 mg/kg/bwt/day) caused a significant (p<0.05) improvement in body weight of treated animals compared with untreated hypercholesterolemia control rats. The extracts also protected significantly (p<0.05) against atherogenic diet induced liver damage or fatty streaks formation in the aorta as revealed by histological examination. The anti-cholesterolemia and anti-atherosclerotic activities of the extract compared favorably well with standard drugs Gemfibrozil and Atorvastatin respectively. Conclusively, rhizomes of T. violacea possess significant anti-atherogenic activity and its mechanism of action(s) may be due to its antioxidant and anti-hypercholesterolemia properties. The results of this study also suggested that rhizome of T. violacea is relatively safe for human consumption and it may be used as an alternative to garlic.
- Full Text:
- Date Issued: 2012
Biological synthesis of metallic nanoparticles and their interactions with various biomedical targets
- Authors: Sennuga, Afolake Temitope
- Date: 2012
- Subjects: Nanoparticles Biosynthesis Nanotechnology Biomineralization Morphology Ceruloplasmin Ribonucleases Adenosine triphosphatase Acetylcholinesterase Platinum Gold Silver
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4009 , http://hdl.handle.net/10962/d1004069
- Description: The synthesis of nanostructured materials, especially metallic nanoparticles, has accrued utmost interest over the past decade owing to their unique properties that make them applicable in different fields of science and technology. The limitation to the use of these nanoparticles is the paucity of an effective method of synthesis that will produce homogeneous size and shape nanoparticles as well as particles with limited or no toxicity to the human health and the environment. The biological method of nanoparticle synthesis is a relatively simple, cheap and environmentally friendly method than the conventional chemical method of synthesis and thus gains an upper hand. The biomineralization of nanoparticles in protein cages is one of such biological approaches used in the generation of nanoparticles. This method of synthesis apart from being a safer method in the production of nanoparticles is also able to control particle morphology. In this study, a comparative biological synthesis, characterization and biomedical effects of metallic nanoparticles of platinum, gold and silver were investigated. Metallic nanoparticles were biologically synthesized using cage-like (apoferritin), barrel-like (GroEL) and non-caged (ribonuclease) proteins. Nanoparticles generated were characterized using common techniques such as UV-visible spectroscopy, scanning and transmission electron microscopy, inductively coupled optical emission spectroscopy, Fourier transform infra-red spectroscopy and energy dispersion analysis of X-rays (EDAX). Nanoparticles synthesised biologically using apoferritin, GroEL and RNase with exhibited similar chemical and physical properties as thoses nanoparticles generated chemically. In addition, the metallic nanoparticles fabricated within the cage-like and barrel-like cavities of apoferritin and GroEL respectively, resulted in nanoparticles with relatively uniform morphology as opposed to those obtained with the non-caged ribonuclease. The enzymatic (ferroxidase) activity of apoferritin was found to be greatly enhanced with platinum (9-fold), gold (7-fold) and silver (54-fold) nanoparticles. The ATPase activity of GroEL was inhibited by silver nanoparticles (64%), was moderately activated by gold nanoparticles (47%) and considerably enhanced by platinum nanoparticles (85%). The hydrolytic activity of RNase was however, lowered by these metallic nanoparticles (90% in Ag nanoparticles) and to a higher degree with platinum (95%) and gold nanoparticles (~100%). The effect of synthesized nanoparticles on the respective enzyme activities of these proteins was also investigated and the potential neurotoxic property of these particles was also determined by an in vitro interaction with acetylcholinesterase. Protein encapsulated nanoparticles with apoferrtin and GroEL showed a decreased inhibition of acetylcholinesterase (<50%) compared with nanoparticles attached to ribonuclease (>50%). Thus, it can be concluded that the cavities of apoferitin and GroEL acted as nanobiofactories for the synthesis and confinement of the size and shape of nanoparticles. Furthermore, the interior of these proteins provided a shielding effect for these nanoparticles and thus reduced/prevented their possible neurotoxic effect and confirmed safety in their method of production and application. The findings from this study would prove beneficial in the application of these nanoparticles as a potential drug/drug delivery vehicle for the prevention, treatment/management of diseases associated with these enzymes/proteins.
- Full Text:
- Date Issued: 2012
- Authors: Sennuga, Afolake Temitope
- Date: 2012
- Subjects: Nanoparticles Biosynthesis Nanotechnology Biomineralization Morphology Ceruloplasmin Ribonucleases Adenosine triphosphatase Acetylcholinesterase Platinum Gold Silver
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4009 , http://hdl.handle.net/10962/d1004069
- Description: The synthesis of nanostructured materials, especially metallic nanoparticles, has accrued utmost interest over the past decade owing to their unique properties that make them applicable in different fields of science and technology. The limitation to the use of these nanoparticles is the paucity of an effective method of synthesis that will produce homogeneous size and shape nanoparticles as well as particles with limited or no toxicity to the human health and the environment. The biological method of nanoparticle synthesis is a relatively simple, cheap and environmentally friendly method than the conventional chemical method of synthesis and thus gains an upper hand. The biomineralization of nanoparticles in protein cages is one of such biological approaches used in the generation of nanoparticles. This method of synthesis apart from being a safer method in the production of nanoparticles is also able to control particle morphology. In this study, a comparative biological synthesis, characterization and biomedical effects of metallic nanoparticles of platinum, gold and silver were investigated. Metallic nanoparticles were biologically synthesized using cage-like (apoferritin), barrel-like (GroEL) and non-caged (ribonuclease) proteins. Nanoparticles generated were characterized using common techniques such as UV-visible spectroscopy, scanning and transmission electron microscopy, inductively coupled optical emission spectroscopy, Fourier transform infra-red spectroscopy and energy dispersion analysis of X-rays (EDAX). Nanoparticles synthesised biologically using apoferritin, GroEL and RNase with exhibited similar chemical and physical properties as thoses nanoparticles generated chemically. In addition, the metallic nanoparticles fabricated within the cage-like and barrel-like cavities of apoferritin and GroEL respectively, resulted in nanoparticles with relatively uniform morphology as opposed to those obtained with the non-caged ribonuclease. The enzymatic (ferroxidase) activity of apoferritin was found to be greatly enhanced with platinum (9-fold), gold (7-fold) and silver (54-fold) nanoparticles. The ATPase activity of GroEL was inhibited by silver nanoparticles (64%), was moderately activated by gold nanoparticles (47%) and considerably enhanced by platinum nanoparticles (85%). The hydrolytic activity of RNase was however, lowered by these metallic nanoparticles (90% in Ag nanoparticles) and to a higher degree with platinum (95%) and gold nanoparticles (~100%). The effect of synthesized nanoparticles on the respective enzyme activities of these proteins was also investigated and the potential neurotoxic property of these particles was also determined by an in vitro interaction with acetylcholinesterase. Protein encapsulated nanoparticles with apoferrtin and GroEL showed a decreased inhibition of acetylcholinesterase (<50%) compared with nanoparticles attached to ribonuclease (>50%). Thus, it can be concluded that the cavities of apoferitin and GroEL acted as nanobiofactories for the synthesis and confinement of the size and shape of nanoparticles. Furthermore, the interior of these proteins provided a shielding effect for these nanoparticles and thus reduced/prevented their possible neurotoxic effect and confirmed safety in their method of production and application. The findings from this study would prove beneficial in the application of these nanoparticles as a potential drug/drug delivery vehicle for the prevention, treatment/management of diseases associated with these enzymes/proteins.
- Full Text:
- Date Issued: 2012
Challenges of instructional leadership in historically disadvantaged schools in South Africa
- Authors: Tshazibana, Vukile Shadrack
- Date: 2012
- Subjects: School management and organization -- South Africa , Educational leadership -- South Africa , Children with social disabilities -- Education -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9565 , http://hdl.handle.net/10948/d1016059
- Description: The research presented in this thesis investigates challenges faced by principals in historically disadvantaged schools in terms of their role as instructional leaders facilitating the implementation of curriculum policies. The study consists of two parts. The first study sampled 25 school principals, 80 teachers and 11 department of education officials from the Uitenhage and Port Elizabeth education districts in the Eastern Cape. Data obtained in the first study were generated by administering a pen-and-paper questionnaire and individual interviews to selected participants. The second study employed an online questionnaire that was open to principals, teachers and departmental officials in all provinces of South Africa in order to generate data over as wide a geographic range as possible. Mixed methods were used to analyse the qualitative and quantitative data from the two studies. Thematic analysis techniques were employed to categorise qualitative data and the quantitative data were subjected to analytical techniques to provide descriptive and inferential statistics. The data revealed that school principals view themselves as change agents who should be in the forefront of change and curriculum implementation, and that they believe that they know what is expected of them in this regard. However, they recognise that they are not adequately prepared for the task of instructional leadership. The data also suggest that teachers have expectations that principals should be trained in instructional leadership and work closely with departmental officials in order to provide guidance and leadership at school level to address their professional needs. Problems related to capacity and skills of subject advisors and other district officials were revealed by the study. These issues are generally and informally recognised, but have not been formally raised within the Department of Education. The findings of the study also highlight the fact that, after nearly two decades in the new political dispensation, there are still vast differences within the South African schooling system between school types. These differences are most evident between ex-Model C schools and historically disadvantaged ex-DET schools, and it is recognised that principals in ex-DET schools need support tailored to their particular circumstances and context. The findings in this study support the notion that much needs to be done in South Africa in terms of empowering school principals; especially those from historically disadvantaged schools. The data provide insights into some of the constraints of local context, which enables better understandings of the challenges of instructional leadership in historically disadvantaged schools. These understandings should be of value when considering strategies to support principals in their role of instructional leaders.
- Full Text:
- Date Issued: 2012
- Authors: Tshazibana, Vukile Shadrack
- Date: 2012
- Subjects: School management and organization -- South Africa , Educational leadership -- South Africa , Children with social disabilities -- Education -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9565 , http://hdl.handle.net/10948/d1016059
- Description: The research presented in this thesis investigates challenges faced by principals in historically disadvantaged schools in terms of their role as instructional leaders facilitating the implementation of curriculum policies. The study consists of two parts. The first study sampled 25 school principals, 80 teachers and 11 department of education officials from the Uitenhage and Port Elizabeth education districts in the Eastern Cape. Data obtained in the first study were generated by administering a pen-and-paper questionnaire and individual interviews to selected participants. The second study employed an online questionnaire that was open to principals, teachers and departmental officials in all provinces of South Africa in order to generate data over as wide a geographic range as possible. Mixed methods were used to analyse the qualitative and quantitative data from the two studies. Thematic analysis techniques were employed to categorise qualitative data and the quantitative data were subjected to analytical techniques to provide descriptive and inferential statistics. The data revealed that school principals view themselves as change agents who should be in the forefront of change and curriculum implementation, and that they believe that they know what is expected of them in this regard. However, they recognise that they are not adequately prepared for the task of instructional leadership. The data also suggest that teachers have expectations that principals should be trained in instructional leadership and work closely with departmental officials in order to provide guidance and leadership at school level to address their professional needs. Problems related to capacity and skills of subject advisors and other district officials were revealed by the study. These issues are generally and informally recognised, but have not been formally raised within the Department of Education. The findings of the study also highlight the fact that, after nearly two decades in the new political dispensation, there are still vast differences within the South African schooling system between school types. These differences are most evident between ex-Model C schools and historically disadvantaged ex-DET schools, and it is recognised that principals in ex-DET schools need support tailored to their particular circumstances and context. The findings in this study support the notion that much needs to be done in South Africa in terms of empowering school principals; especially those from historically disadvantaged schools. The data provide insights into some of the constraints of local context, which enables better understandings of the challenges of instructional leadership in historically disadvantaged schools. These understandings should be of value when considering strategies to support principals in their role of instructional leaders.
- Full Text:
- Date Issued: 2012
Characterisation and optimisation of waterjet impact forces and energy parameters during hydroentanglement
- Authors: Moyo, Doice
- Date: 2012
- Subjects: Textile chemistry , Nonwoven fabrics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10453 , http://hdl.handle.net/10948/d1020134
- Description: Hydroentanglement is an important technique of bonding fibres to produce nonwovens using high velocity waterjets as the primary bonding tool. The work reported in this thesis addresses the gap in scientific knowledge and understanding, both theoretical and experimental, related to the impact forces and energy of the waterjets used in the hydroentanglement process. The current study focused on the impact forces and energy involved in, and the optimisation of, the hydroentanglement process. The results of the experimentally measured waterjet impact forces have been used to characterise the waterjets as well as to verify empirically the theoretical models currently available for explaining the mechanics of the hydroentanglement process. Since the process of supplying pressurised waterjets consumes a great deal of energy, the study of energy consumption and efficiency of the system has been critical. A method was proposed and used to determine the coefficients of velocity and water discharge of an industrial machine set-up, helping explain the mechanism of energy transfer during hydroentanglement and to concurrently optimise the process. Furthermore, a response surface experimental design was used to optimise the hydroentanglement of viscose and Polylactic acid (PLA) fibres into nonwovens. The selected Box-Behnken design, with four factors, namely the waterjet force, machine processing speed, input weight and fibre type, was employed to investigate the multivariate process factors and their interactive effects on physical and mechanical properties of nonwovens. Two sets of experiments, the later for validation, were performed to study the energy transfer efficiency. The results of the relative energy transfer to bond the fibrous web showed that it was possible to produce nonwovens using lower input energy without compromising the quality of the products. The optimum waterjet pressure and machine speed used to produce the Abstract nonwoven with the highest tensile strength for the least amount of energy supplied were identified.
- Full Text:
- Date Issued: 2012
- Authors: Moyo, Doice
- Date: 2012
- Subjects: Textile chemistry , Nonwoven fabrics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10453 , http://hdl.handle.net/10948/d1020134
- Description: Hydroentanglement is an important technique of bonding fibres to produce nonwovens using high velocity waterjets as the primary bonding tool. The work reported in this thesis addresses the gap in scientific knowledge and understanding, both theoretical and experimental, related to the impact forces and energy of the waterjets used in the hydroentanglement process. The current study focused on the impact forces and energy involved in, and the optimisation of, the hydroentanglement process. The results of the experimentally measured waterjet impact forces have been used to characterise the waterjets as well as to verify empirically the theoretical models currently available for explaining the mechanics of the hydroentanglement process. Since the process of supplying pressurised waterjets consumes a great deal of energy, the study of energy consumption and efficiency of the system has been critical. A method was proposed and used to determine the coefficients of velocity and water discharge of an industrial machine set-up, helping explain the mechanism of energy transfer during hydroentanglement and to concurrently optimise the process. Furthermore, a response surface experimental design was used to optimise the hydroentanglement of viscose and Polylactic acid (PLA) fibres into nonwovens. The selected Box-Behnken design, with four factors, namely the waterjet force, machine processing speed, input weight and fibre type, was employed to investigate the multivariate process factors and their interactive effects on physical and mechanical properties of nonwovens. Two sets of experiments, the later for validation, were performed to study the energy transfer efficiency. The results of the relative energy transfer to bond the fibrous web showed that it was possible to produce nonwovens using lower input energy without compromising the quality of the products. The optimum waterjet pressure and machine speed used to produce the Abstract nonwoven with the highest tensile strength for the least amount of energy supplied were identified.
- Full Text:
- Date Issued: 2012
Commensal bacteria belonging to the Staphylococcus Acinetobacter and Stenotrophomonas genera as reservoirs of antibiotic resistance determinants in the environment of Nkonkobe Municipality, Eastern Cape Province , South Africa
- Authors: Adegoke, Anthony Ayodeji
- Date: 2012
- Subjects: Acinetobacter infections , Drug resistance in microorganisms , Staphylococcal infections , Bacterial diseases
- Language: English
- Type: Thesis , Doctoral , Degree
- Identifier: http://hdl.handle.net/10353/6539 , vital:30551
- Description: A study to assess the potentials of some commensal bacteria that belong to Staphylococcus, Acinetobacter and Stenotrophomonas genera as reservoirs of antibiotic resistance determinants in the environment of Nkonkobe Municipality of the Eastern Cape Province, South Africa, was carried out using standard microbiological and molecular techniques. A total of 120 Staphylococcus isolates which consisted of Staphylococcus haemolyticus (30%), Staphylococcus aureus (23.3%) from pig; Staphylococcus capitis (15%) from goat; Staphylococcus heamolyticus (5%) and Staphylococcus xylosus (15%) from cattle and other Staphylococci (11%) from dead chicken and pigs were isolated. About 23.3% of these isolates were coagulase positive and 76.7% were coagulase negative. This difference in prevalence along coagulase production divide was statistically significant (p < 0.05). Eighty-six Acinetobacter species (Acinetobacter baumannii/calcoaceticus and Acinetobacter haemolyticus) were also isolated from Alice and Fort Beaufort towns samples, while 125 Stenotrophomonas maltophilia isolates were from grass root rhizosphere (96%) and soil butternut root rhizosphere (4%). Between 75-100% of the Staphylococccus species were resistant to Penicillin G, tetracycline, sulphamethaxole and nalidixic acid; about 38 % were methicillin resistant, consisting of 12.6% methicillin resistant Staphylococcus aureus (MRSA) from pig and a total of 12% vancomycin resistant were observed. Also, 12% of the isolates were erythromycin resistant while 40.2 % were resistant to the third generation cephalosporin, ceftazidime. The antibiotic resistance genes vanA, VanB, eryA, eryB, eryC were not detected in all the phenotypically resistant Staphylococccus species, but mec A gene and mph genes were detected. In the Acinetobacter species, a wide range of 30-100% resistance to penicillin G, ceftriazone, nitrofurantoin, erythromycin, and augmentin was observed. Polymerase chain reaction (PCR) revealed the presence of Tet(B) and Tet(39) genes in these species, while Tet (A), Tet(M) and Tet(H) were absent. Also, 9.3% of the Acinetobacter species showed phenotypic production of extended spectrum beta lactamases (ESBLs) while 3.5% were positive for the presence of blaCTX-M-1 genes. The Stenotrophomonas maltophilia isolates showed varying resistance to meropenem (8.9%), cefuroxime (95.6 %), ampicillin-sulbactam (53.9%), ceftazidime (10.7%), cefepime (29.3 %), minocycline (2.2%), kanamycin (56.9%), ofloxacin (2.9%), levofloxacin (1.3%), moxifloxacin (2.8%), ciprofloxacin (24.3%), gatifloxacin (1.3%), polymyxin B (2.9 %), cotrimoxazole (26.1%), trimethoprim (98.6%), aztreonam(58%) and Polymyxin B (2.9 %). The isolates exhibited significant susceptibility to the fluoroquinolones (74.3-94.7 %), polymycin (97.1%) and meropenem (88.1%). Only sul3 genes were the only sulphonamide resistance gene detected among the trimethoprim-sulphamethoxazole resistant isolates. The observed multiple antibiotic resistance indeces (MARI) of >2 for Staphylococcus species, Acinetobacter species and Stenotrophomonas maltophilia suggest that they have arisen from high-risk sources where antibiotics are in constant arbitrary use resulting in high selective pressure. The presence of tetracycline resistance genes in Acinetobacter species justifies the observed phenotypic resistance to oxytetracycline and intermediate resistance to minocycline. High phenotypic resistance and the presence of some resistance genes in Staphylococcus species is a possible threat to public health and suggests animals to be important reservoirs of antibiotic resistance determinants in the environment. Indiscriminate use of antibiotics induces this kind of antibiotic resistance and should be discouraged. Personal hygiene is encouraged as it reduces the load of Acinetobacter species contacted from the environment that may be difficult to control. Commensal Stenotrophomonas maltophilia are as important as their clinical counterparts due to their roles in opportunistic infection, antibiotic resistance and their associated genes, especially sul gene. Personal hygiene is hereby advocated especially when in contact with soil, plants and plants’ rhizospheric soil.
- Full Text:
- Date Issued: 2012
- Authors: Adegoke, Anthony Ayodeji
- Date: 2012
- Subjects: Acinetobacter infections , Drug resistance in microorganisms , Staphylococcal infections , Bacterial diseases
- Language: English
- Type: Thesis , Doctoral , Degree
- Identifier: http://hdl.handle.net/10353/6539 , vital:30551
- Description: A study to assess the potentials of some commensal bacteria that belong to Staphylococcus, Acinetobacter and Stenotrophomonas genera as reservoirs of antibiotic resistance determinants in the environment of Nkonkobe Municipality of the Eastern Cape Province, South Africa, was carried out using standard microbiological and molecular techniques. A total of 120 Staphylococcus isolates which consisted of Staphylococcus haemolyticus (30%), Staphylococcus aureus (23.3%) from pig; Staphylococcus capitis (15%) from goat; Staphylococcus heamolyticus (5%) and Staphylococcus xylosus (15%) from cattle and other Staphylococci (11%) from dead chicken and pigs were isolated. About 23.3% of these isolates were coagulase positive and 76.7% were coagulase negative. This difference in prevalence along coagulase production divide was statistically significant (p < 0.05). Eighty-six Acinetobacter species (Acinetobacter baumannii/calcoaceticus and Acinetobacter haemolyticus) were also isolated from Alice and Fort Beaufort towns samples, while 125 Stenotrophomonas maltophilia isolates were from grass root rhizosphere (96%) and soil butternut root rhizosphere (4%). Between 75-100% of the Staphylococccus species were resistant to Penicillin G, tetracycline, sulphamethaxole and nalidixic acid; about 38 % were methicillin resistant, consisting of 12.6% methicillin resistant Staphylococcus aureus (MRSA) from pig and a total of 12% vancomycin resistant were observed. Also, 12% of the isolates were erythromycin resistant while 40.2 % were resistant to the third generation cephalosporin, ceftazidime. The antibiotic resistance genes vanA, VanB, eryA, eryB, eryC were not detected in all the phenotypically resistant Staphylococccus species, but mec A gene and mph genes were detected. In the Acinetobacter species, a wide range of 30-100% resistance to penicillin G, ceftriazone, nitrofurantoin, erythromycin, and augmentin was observed. Polymerase chain reaction (PCR) revealed the presence of Tet(B) and Tet(39) genes in these species, while Tet (A), Tet(M) and Tet(H) were absent. Also, 9.3% of the Acinetobacter species showed phenotypic production of extended spectrum beta lactamases (ESBLs) while 3.5% were positive for the presence of blaCTX-M-1 genes. The Stenotrophomonas maltophilia isolates showed varying resistance to meropenem (8.9%), cefuroxime (95.6 %), ampicillin-sulbactam (53.9%), ceftazidime (10.7%), cefepime (29.3 %), minocycline (2.2%), kanamycin (56.9%), ofloxacin (2.9%), levofloxacin (1.3%), moxifloxacin (2.8%), ciprofloxacin (24.3%), gatifloxacin (1.3%), polymyxin B (2.9 %), cotrimoxazole (26.1%), trimethoprim (98.6%), aztreonam(58%) and Polymyxin B (2.9 %). The isolates exhibited significant susceptibility to the fluoroquinolones (74.3-94.7 %), polymycin (97.1%) and meropenem (88.1%). Only sul3 genes were the only sulphonamide resistance gene detected among the trimethoprim-sulphamethoxazole resistant isolates. The observed multiple antibiotic resistance indeces (MARI) of >2 for Staphylococcus species, Acinetobacter species and Stenotrophomonas maltophilia suggest that they have arisen from high-risk sources where antibiotics are in constant arbitrary use resulting in high selective pressure. The presence of tetracycline resistance genes in Acinetobacter species justifies the observed phenotypic resistance to oxytetracycline and intermediate resistance to minocycline. High phenotypic resistance and the presence of some resistance genes in Staphylococcus species is a possible threat to public health and suggests animals to be important reservoirs of antibiotic resistance determinants in the environment. Indiscriminate use of antibiotics induces this kind of antibiotic resistance and should be discouraged. Personal hygiene is encouraged as it reduces the load of Acinetobacter species contacted from the environment that may be difficult to control. Commensal Stenotrophomonas maltophilia are as important as their clinical counterparts due to their roles in opportunistic infection, antibiotic resistance and their associated genes, especially sul gene. Personal hygiene is hereby advocated especially when in contact with soil, plants and plants’ rhizospheric soil.
- Full Text:
- Date Issued: 2012
Comparative biogeography and ecology of freshwater fishes in the Breede and associated river systems, South Africa
- Authors: Chakona, Albert
- Date: 2012
- Subjects: Freshwater fishes -- South Africa -- Breede River , Freshwater fishes -- South Africa -- Geographical distribution , Freshwater fishes -- Ecology , Feshwater fishes -- Genetics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5372 , http://hdl.handle.net/10962/d1015694
- Description: Distribution patterns and levels of genetic diversity in extant taxa are a product of complex palaeogeographic processes and climatic oscillations as well as the species’ intrinsic ecological adaptations. The Cape Floristic Region of South Africa presents a unique system for studying the processes that promote species diversification and distribution patterns. This region has a high degree of endemism of both terrestrial and aquatic biota and is clearly isolated from neighbouring areas by the Cape Fold Mountains and the Great Escarpment. The objective of this study was to firstly examine the ecology of freshwater fishes belonging to the genera Galaxias, Pseudobarbus and Sandelia in the south-western CFR. This was followed by an assessment of the genetic diversity of these taxa. Unique lineages were identified and their distribution was mapped. The work aimed to explore the role of the region’s complex palaeogeographic and climatic history as well as the role of the species’ ecological adaptations in driving lineage diversification and shaping contemporary distribution patterns. The four main components of the study can be summarised as follows: 1. Habitat associations of three widely distributed lineages of Galaxias zebratus Pseudobarbus burchelli and Sandelia capensis were evaluated at multiple localities in minimally disturbed mountain tributaries of the Breede, Duiwenhoks and Goukou River systems. The lineages have distinct habitat associations which were related to differences in their morphological traits. The slender-bodied Galaxias ‘nebula’ and the fusiform-shaped Pseudobarbus ‘Breede’ are capable of exploiting upper reaches with faster water velocity. By contrast, the laterally compressed Sandelia ‘eastern’ is restricted to lower reaches, making this lineage more susceptible to a wide array of impacts. 2. A recently discovered lineage of Galaxias zebratus, (Galaxias ‘nebula’), was found to be capable of tolerating emersion for a prolonged period of time. This is the first time that such capabilities have been documented in an African galaxiid. These adaptations have implications for the interpretation of Galaxias ‘nebula’s wide distribution range. 3. The phylogeography of Galaxias ‘nebula’ across its entire distribution range was investigated using two mitochondrial genes (cytochrome c oxidase subunit I (COI) and cytochrome b (cyt b)). This lineage has a complex evolutionary history that was influenced by both intrinsic and extrinsic factors. Rare events such as episodic drainage connections during Pleistocene and Holocene pluvial periods, possibly augmented by river confluences during periods of lower sea-levels and river capture events seem to be the most credible explanation for the extensive contemporary distribution and the relatively shallow genetic divergence between different river systems. 4. Mitochondrial cyt b sequences were used (i) to assess genetic diversity in G. zebratus, P. burchelli and S. capensis from the south-western CFR and (ii) to determine the roles of intrinsic ecological adaptations and extrinsic landscape and climatic changes in promoting genetic diversification and shaping present day distribution patterns of lineages in the three taxa. Marine incursions during periods of major sea-level transgressions are proposed to have isolated populations in upland refugia, thereby driving allopatric divergence in these species. Subsequent connections of rivers during wetter periods and lower sea-levels are proposed to have facilitated post-speciation dispersal of lineages to attain present day distribution patterns. While detailed morphological studies and further genetic analysis are needed to substantiate the taxonomic status of the newly discovered lineages of Galaxias zebratus, Pseudobarbus burchelli and Sandelia capensis, results of the present study indicate that the south-western CFR represents a previously unrecognised centre of freshwater fish diversity and microendemism in the broader Cape Floristic Region. Accurate identification of lineages and comprehensive mapping of their distribution is a fundamental pre-requisite for ecological studies, assessing conservation status and implementation of appropriate conservation measures.
- Full Text:
- Date Issued: 2012
- Authors: Chakona, Albert
- Date: 2012
- Subjects: Freshwater fishes -- South Africa -- Breede River , Freshwater fishes -- South Africa -- Geographical distribution , Freshwater fishes -- Ecology , Feshwater fishes -- Genetics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5372 , http://hdl.handle.net/10962/d1015694
- Description: Distribution patterns and levels of genetic diversity in extant taxa are a product of complex palaeogeographic processes and climatic oscillations as well as the species’ intrinsic ecological adaptations. The Cape Floristic Region of South Africa presents a unique system for studying the processes that promote species diversification and distribution patterns. This region has a high degree of endemism of both terrestrial and aquatic biota and is clearly isolated from neighbouring areas by the Cape Fold Mountains and the Great Escarpment. The objective of this study was to firstly examine the ecology of freshwater fishes belonging to the genera Galaxias, Pseudobarbus and Sandelia in the south-western CFR. This was followed by an assessment of the genetic diversity of these taxa. Unique lineages were identified and their distribution was mapped. The work aimed to explore the role of the region’s complex palaeogeographic and climatic history as well as the role of the species’ ecological adaptations in driving lineage diversification and shaping contemporary distribution patterns. The four main components of the study can be summarised as follows: 1. Habitat associations of three widely distributed lineages of Galaxias zebratus Pseudobarbus burchelli and Sandelia capensis were evaluated at multiple localities in minimally disturbed mountain tributaries of the Breede, Duiwenhoks and Goukou River systems. The lineages have distinct habitat associations which were related to differences in their morphological traits. The slender-bodied Galaxias ‘nebula’ and the fusiform-shaped Pseudobarbus ‘Breede’ are capable of exploiting upper reaches with faster water velocity. By contrast, the laterally compressed Sandelia ‘eastern’ is restricted to lower reaches, making this lineage more susceptible to a wide array of impacts. 2. A recently discovered lineage of Galaxias zebratus, (Galaxias ‘nebula’), was found to be capable of tolerating emersion for a prolonged period of time. This is the first time that such capabilities have been documented in an African galaxiid. These adaptations have implications for the interpretation of Galaxias ‘nebula’s wide distribution range. 3. The phylogeography of Galaxias ‘nebula’ across its entire distribution range was investigated using two mitochondrial genes (cytochrome c oxidase subunit I (COI) and cytochrome b (cyt b)). This lineage has a complex evolutionary history that was influenced by both intrinsic and extrinsic factors. Rare events such as episodic drainage connections during Pleistocene and Holocene pluvial periods, possibly augmented by river confluences during periods of lower sea-levels and river capture events seem to be the most credible explanation for the extensive contemporary distribution and the relatively shallow genetic divergence between different river systems. 4. Mitochondrial cyt b sequences were used (i) to assess genetic diversity in G. zebratus, P. burchelli and S. capensis from the south-western CFR and (ii) to determine the roles of intrinsic ecological adaptations and extrinsic landscape and climatic changes in promoting genetic diversification and shaping present day distribution patterns of lineages in the three taxa. Marine incursions during periods of major sea-level transgressions are proposed to have isolated populations in upland refugia, thereby driving allopatric divergence in these species. Subsequent connections of rivers during wetter periods and lower sea-levels are proposed to have facilitated post-speciation dispersal of lineages to attain present day distribution patterns. While detailed morphological studies and further genetic analysis are needed to substantiate the taxonomic status of the newly discovered lineages of Galaxias zebratus, Pseudobarbus burchelli and Sandelia capensis, results of the present study indicate that the south-western CFR represents a previously unrecognised centre of freshwater fish diversity and microendemism in the broader Cape Floristic Region. Accurate identification of lineages and comprehensive mapping of their distribution is a fundamental pre-requisite for ecological studies, assessing conservation status and implementation of appropriate conservation measures.
- Full Text:
- Date Issued: 2012
Conveniencing the family in agri-based processing enterprise : a grounded theory study of strategic leaders' cultural assumptions and strategising activities
- Authors: Kanyangale, Macdonald Isaac
- Date: 2012
- Subjects: Small business -- Malawi -- Management Agriculture -- Malawi -- Business management Agriculture -- Economic aspects -- Malawi Grounded theory -- Study and teaching
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1181 , http://hdl.handle.net/10962/d1002798
- Description: As leaders of small and medium enterprises (SMEs), strategic leaders are responsible for strategising, the approach to which is influenced by their cultural paradigm. The effects of this strategising are manifested in the day-to-day activities of these leaders. This study aims to build an understanding of the shared cultural assumptions of strategic leaders in agri-based processing SMEs and how these assumptions affect the strategising activities that are adopted when addressing critical incidents related to the internal integration and external adaptation of the SME. Using Strauss and Corbin‟s (1990) grounded theory method, this study develops a theory titled Conveniencing the Family in Business, which is induced from critical incidents. A sample of critical incidents was gathered from 44 qualitative interviews conducted with strategic leaders of various agri-based processing SMEs operating in Malawi. This study found that strategic leaders display persistent and stable pragmatic business survival mind sets, but dynamic cultural assumptions about relationships with organisation members. The cultural influence of these assumptions is manifested in two distinctive and alternative processes making up the theory of conveniencing the family in business. These are the humanising and commodifying of relationships with organisation members, and they are evident in hostile and friendly business environments, respectively. Humanising of relationships with all members of the organisation builds and capitalises on inclusive, organisation-wide social capital that secures the future of the business. On the other hand, commodifying of relationships with non-family organisation members weakens collective support, which becomes mainly dependent on family and friendship ties. Thus, commodifying of relationships serves to perpetuate the close integration of business activity and family requirements to ultimately convenience the family in business, and represents the desired modus operandi of strategic leaders. As strategic leaders of SMEs have not yet conceptualised this, providing them with the conceptual theory developed here may be helpful towards a consistent re-orientation of the internal organisational support in a way that does not exclude but rather harnesses the wider solidarity of organisation members. The process explained by this theory is iterative, dynamic and distinguishes patterns of relationships amongst organisation members, which either enhances or compromises their collective support for the leaders and the enterprise. This by implication affects the performance of the enterprise. The results of this study are discussed from the perspective of social exchange and social capital theory, thereby contributing to the understanding of the strategising activities of strategic leaders, as well as the processes of building or destroying social capital in this type of enterprise.
- Full Text:
- Date Issued: 2012
- Authors: Kanyangale, Macdonald Isaac
- Date: 2012
- Subjects: Small business -- Malawi -- Management Agriculture -- Malawi -- Business management Agriculture -- Economic aspects -- Malawi Grounded theory -- Study and teaching
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1181 , http://hdl.handle.net/10962/d1002798
- Description: As leaders of small and medium enterprises (SMEs), strategic leaders are responsible for strategising, the approach to which is influenced by their cultural paradigm. The effects of this strategising are manifested in the day-to-day activities of these leaders. This study aims to build an understanding of the shared cultural assumptions of strategic leaders in agri-based processing SMEs and how these assumptions affect the strategising activities that are adopted when addressing critical incidents related to the internal integration and external adaptation of the SME. Using Strauss and Corbin‟s (1990) grounded theory method, this study develops a theory titled Conveniencing the Family in Business, which is induced from critical incidents. A sample of critical incidents was gathered from 44 qualitative interviews conducted with strategic leaders of various agri-based processing SMEs operating in Malawi. This study found that strategic leaders display persistent and stable pragmatic business survival mind sets, but dynamic cultural assumptions about relationships with organisation members. The cultural influence of these assumptions is manifested in two distinctive and alternative processes making up the theory of conveniencing the family in business. These are the humanising and commodifying of relationships with organisation members, and they are evident in hostile and friendly business environments, respectively. Humanising of relationships with all members of the organisation builds and capitalises on inclusive, organisation-wide social capital that secures the future of the business. On the other hand, commodifying of relationships with non-family organisation members weakens collective support, which becomes mainly dependent on family and friendship ties. Thus, commodifying of relationships serves to perpetuate the close integration of business activity and family requirements to ultimately convenience the family in business, and represents the desired modus operandi of strategic leaders. As strategic leaders of SMEs have not yet conceptualised this, providing them with the conceptual theory developed here may be helpful towards a consistent re-orientation of the internal organisational support in a way that does not exclude but rather harnesses the wider solidarity of organisation members. The process explained by this theory is iterative, dynamic and distinguishes patterns of relationships amongst organisation members, which either enhances or compromises their collective support for the leaders and the enterprise. This by implication affects the performance of the enterprise. The results of this study are discussed from the perspective of social exchange and social capital theory, thereby contributing to the understanding of the strategising activities of strategic leaders, as well as the processes of building or destroying social capital in this type of enterprise.
- Full Text:
- Date Issued: 2012
Corporate social responsibility: a competitive strategy for small and medium-sized enterprises in Uganda
- Authors: Turyakira, Peter
- Date: 2012
- Subjects: Competition , Social responsibility of business -- Uganda , Corporate culture -- Uganda , Corporations -- Moral and ethical aspects
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9295 , http://hdl.handle.net/10948/d1012648 , Competition , Social responsibility of business -- Uganda , Corporate culture -- Uganda , Corporations -- Moral and ethical aspects
- Description: In view of the important role small and medium-sized enterprises (SMEs) universally play as the backbone of national economies and the survival and competitiveness challenges that they face, the purpose of this study was to develop specific models of corporate social responsibility (CSR) for SMEs in Uganda as an avenue to enhance their competitiveness and foster economic development. The primary objective was to gain insight into the deployment of CSR in SMEs, including investigating CSR factors and their potential impact on competitiveness. This study integrates previous findings and theories on CSR activities and SMEs‟ competitiveness into a comprehensive hypothesised model. A comprehensive literature study revealed potential factors that could influence the Increased competitiveness of SMEs in Uganda. Four independent variables (Workforce-oriented, Society-oriented, Market-oriented and Environmental-oriented CSR activities) and three mediating variables (Employee satisfaction, Business reputation and Customer loyalty) were identified as variables influencing the Increased competitiveness (dependent variable) of SMEs. Independent variables were categorised as CSR factors while mediating and dependent variables were categorised as outcomes factors. Furthermore, hypotheses were formulated for possible relationships between the independent, mediating and dependent variables. All the variables in the study were clearly defined and operationalised. Reliable and valid items sourced from various measuring instruments used in other similar studies, were used in the operationalisation of these variables. Furthermore, several items were generated from secondary sources. A structured self-administered questionnaire was made available to respondents identified using the stratified and purposive sampling techniques, and the data collected from 383 usable questionnaires was subjected to several statistical analyses. The validity and reliability of the measuring instrument was ascertained using an exploratory factor analysis and Cronbach-alpha coefficients respectively. An exploratory factor analysis using SPSS 18 for Windows was conducted to identify the unique factors available in the data before applying structural equation modelling (SEM). The data were categorised into models of independent variables (CSR factors) and the mediating variables (Outcomes factors). The items measuring Market-oriented CSR activities and Workforce-oriented CSR activities loaded as expected. The items measuring Environmental-oriented CSR activities loaded onto two separate factors which were renamed Environmental-oriented CSR activities and Regulated CSR activities. One of the items originally expected to measure the construct Society-oriented CSR activities loaded onto Environmental-oriented CSR activities, leaving three items which loaded together onto the Society-oriented CSR activities factor. Four factors constituted the outcomes submodel, namely Customer loyalty, Stakeholder trust, Business reputation, and Employee satisfaction. In this study, SEM was the main statistical procedure used to test the significance of the relationships hypothesised between the various independent and dependent variables. Owing to the sample size limitations, the hypothesised model could not be subjected to SEM as a whole. Consequently, six sub-models were identified and subjected to further analysis. The following independent variables were identified as influencing the dependent variables in this study: Workforce-oriented CSR activities, Society-oriented CSR activities, Market-oriented CSR activities, Environmental-oriented CSR activities, Regulated CSR activities. To establish the influence of the various demographic variables on the mediating and dependent variables, an Analysis of Variance (ANOVA) and Multiple Linear Regression (MLR) analysis were conducted. The respondent‟s position/title in the business, form of enterprise, branch/sector of business, level of education, and the size of business were found to have an influence on the mediating and dependent variables of this study. This study has therefore added to the underdeveloped body of business research in Uganda by investigating a particularly limited segment of the literature, namely SMEs. The study has also identified and developed various models that explain the most significant CSR factors that influence the competitiveness of SMEs. Consequently, this study has put forward several recommendations and suggestions that can enhance the competitiveness of SMEs locally and globally. Further research is encouraged on action-oriented areas such as: the success of different policies and techniques to increase the uptake of CSR amongst SMEs; the economic, social and environmental impact of CSR at sector level; and a typology of SMEs with regard to their engagement in CSR.
- Full Text:
- Date Issued: 2012
- Authors: Turyakira, Peter
- Date: 2012
- Subjects: Competition , Social responsibility of business -- Uganda , Corporate culture -- Uganda , Corporations -- Moral and ethical aspects
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9295 , http://hdl.handle.net/10948/d1012648 , Competition , Social responsibility of business -- Uganda , Corporate culture -- Uganda , Corporations -- Moral and ethical aspects
- Description: In view of the important role small and medium-sized enterprises (SMEs) universally play as the backbone of national economies and the survival and competitiveness challenges that they face, the purpose of this study was to develop specific models of corporate social responsibility (CSR) for SMEs in Uganda as an avenue to enhance their competitiveness and foster economic development. The primary objective was to gain insight into the deployment of CSR in SMEs, including investigating CSR factors and their potential impact on competitiveness. This study integrates previous findings and theories on CSR activities and SMEs‟ competitiveness into a comprehensive hypothesised model. A comprehensive literature study revealed potential factors that could influence the Increased competitiveness of SMEs in Uganda. Four independent variables (Workforce-oriented, Society-oriented, Market-oriented and Environmental-oriented CSR activities) and three mediating variables (Employee satisfaction, Business reputation and Customer loyalty) were identified as variables influencing the Increased competitiveness (dependent variable) of SMEs. Independent variables were categorised as CSR factors while mediating and dependent variables were categorised as outcomes factors. Furthermore, hypotheses were formulated for possible relationships between the independent, mediating and dependent variables. All the variables in the study were clearly defined and operationalised. Reliable and valid items sourced from various measuring instruments used in other similar studies, were used in the operationalisation of these variables. Furthermore, several items were generated from secondary sources. A structured self-administered questionnaire was made available to respondents identified using the stratified and purposive sampling techniques, and the data collected from 383 usable questionnaires was subjected to several statistical analyses. The validity and reliability of the measuring instrument was ascertained using an exploratory factor analysis and Cronbach-alpha coefficients respectively. An exploratory factor analysis using SPSS 18 for Windows was conducted to identify the unique factors available in the data before applying structural equation modelling (SEM). The data were categorised into models of independent variables (CSR factors) and the mediating variables (Outcomes factors). The items measuring Market-oriented CSR activities and Workforce-oriented CSR activities loaded as expected. The items measuring Environmental-oriented CSR activities loaded onto two separate factors which were renamed Environmental-oriented CSR activities and Regulated CSR activities. One of the items originally expected to measure the construct Society-oriented CSR activities loaded onto Environmental-oriented CSR activities, leaving three items which loaded together onto the Society-oriented CSR activities factor. Four factors constituted the outcomes submodel, namely Customer loyalty, Stakeholder trust, Business reputation, and Employee satisfaction. In this study, SEM was the main statistical procedure used to test the significance of the relationships hypothesised between the various independent and dependent variables. Owing to the sample size limitations, the hypothesised model could not be subjected to SEM as a whole. Consequently, six sub-models were identified and subjected to further analysis. The following independent variables were identified as influencing the dependent variables in this study: Workforce-oriented CSR activities, Society-oriented CSR activities, Market-oriented CSR activities, Environmental-oriented CSR activities, Regulated CSR activities. To establish the influence of the various demographic variables on the mediating and dependent variables, an Analysis of Variance (ANOVA) and Multiple Linear Regression (MLR) analysis were conducted. The respondent‟s position/title in the business, form of enterprise, branch/sector of business, level of education, and the size of business were found to have an influence on the mediating and dependent variables of this study. This study has therefore added to the underdeveloped body of business research in Uganda by investigating a particularly limited segment of the literature, namely SMEs. The study has also identified and developed various models that explain the most significant CSR factors that influence the competitiveness of SMEs. Consequently, this study has put forward several recommendations and suggestions that can enhance the competitiveness of SMEs locally and globally. Further research is encouraged on action-oriented areas such as: the success of different policies and techniques to increase the uptake of CSR amongst SMEs; the economic, social and environmental impact of CSR at sector level; and a typology of SMEs with regard to their engagement in CSR.
- Full Text:
- Date Issued: 2012
Creating a space for integrative education within the sciences
- Authors: Van der Post, Leda
- Date: 2012
- Subjects: Computer science -- Vocational guidance , Education, Cooperative , Curriculum evaluation , Experiential learning -- Science
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10482 , http://hdl.handle.net/10948/d1012677 , Computer science -- Vocational guidance , Education, Cooperative , Curriculum evaluation , Experiential learning -- Science
- Description: This thesis documents an action research project that was carried out within the Department of Computing Sciences at the Nelson Mandela Metropolitan University (NMMU), South Africa, from January 2010 to December 2011. The overall aim of the research was to foster an environment in which academics could explore ways to teach using an integrative approach to education. Previous research within the department had raised the concern that students were graduating without the type of high-level cognitive skills that were required in the workplace. While the students’ technical skills were perceived as being excellent, employers indicated that students would benefit from opportunities to develop or improve skills such as communication, teamwork, innovative thinking and time management. These skills include high-level cognitive skills, and are often referred to as “soft skills”. The academics participating in the research project came to believe that it was essential to develop teaching methods that would provide opportunities for students to develop these soft skills, in conjunction with the content and technical knowledge currently addressed in their courses. The research project followed the living theory approach to action research. A living theory action research project allows the researcher to investigate her own teaching, and develop a theory of practice. The theory of practice can be applied to the issues under investigation, to improve the situation or solve problems. At the same time, the theory of practice can contribute to the body of knowledge within the academic domain of the research. Action research is an iterative, cyclical process. There were four research cycles, each one semester in length, during the two years of the project. The project will continue, with a fifth research cycle, starting in January 2012. By the end of the fourth research cycle—Semester Two, 2011—there were eleven academics actively participating in the research group. The project had extended its influence to include academics from the Department of Mathematics at NMMU. The academics ranged from senior, long-serving professors to junior lecturing staff. The results of the research, or the researcher-practitioner’s living theory, explain the process by which an effective and enthusiastic community of practice, dedicated to improving the academics’ teaching and learning practice, was developed. The living theory is applicable to academics within a scientific discipline, desiring to explore and improve their education practice. My living theory explains the characteristics of the TLC (The Learning Community) space, and the action strategies for creating such a space. The explanation of the process of this project includes an analysis of the development process of the research group, typical characteristics of the environment or “space” of the group, and action strategies that other academics could use to create a similar community of practice.
- Full Text:
- Date Issued: 2012
- Authors: Van der Post, Leda
- Date: 2012
- Subjects: Computer science -- Vocational guidance , Education, Cooperative , Curriculum evaluation , Experiential learning -- Science
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10482 , http://hdl.handle.net/10948/d1012677 , Computer science -- Vocational guidance , Education, Cooperative , Curriculum evaluation , Experiential learning -- Science
- Description: This thesis documents an action research project that was carried out within the Department of Computing Sciences at the Nelson Mandela Metropolitan University (NMMU), South Africa, from January 2010 to December 2011. The overall aim of the research was to foster an environment in which academics could explore ways to teach using an integrative approach to education. Previous research within the department had raised the concern that students were graduating without the type of high-level cognitive skills that were required in the workplace. While the students’ technical skills were perceived as being excellent, employers indicated that students would benefit from opportunities to develop or improve skills such as communication, teamwork, innovative thinking and time management. These skills include high-level cognitive skills, and are often referred to as “soft skills”. The academics participating in the research project came to believe that it was essential to develop teaching methods that would provide opportunities for students to develop these soft skills, in conjunction with the content and technical knowledge currently addressed in their courses. The research project followed the living theory approach to action research. A living theory action research project allows the researcher to investigate her own teaching, and develop a theory of practice. The theory of practice can be applied to the issues under investigation, to improve the situation or solve problems. At the same time, the theory of practice can contribute to the body of knowledge within the academic domain of the research. Action research is an iterative, cyclical process. There were four research cycles, each one semester in length, during the two years of the project. The project will continue, with a fifth research cycle, starting in January 2012. By the end of the fourth research cycle—Semester Two, 2011—there were eleven academics actively participating in the research group. The project had extended its influence to include academics from the Department of Mathematics at NMMU. The academics ranged from senior, long-serving professors to junior lecturing staff. The results of the research, or the researcher-practitioner’s living theory, explain the process by which an effective and enthusiastic community of practice, dedicated to improving the academics’ teaching and learning practice, was developed. The living theory is applicable to academics within a scientific discipline, desiring to explore and improve their education practice. My living theory explains the characteristics of the TLC (The Learning Community) space, and the action strategies for creating such a space. The explanation of the process of this project includes an analysis of the development process of the research group, typical characteristics of the environment or “space” of the group, and action strategies that other academics could use to create a similar community of practice.
- Full Text:
- Date Issued: 2012
Critical factors for enabling knowledge sharing between government agencies within South Africa
- Authors: Mannie, Avain
- Date: 2012
- Subjects: Administrative agencies , Knowledge management , Business intelligence
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8822 , http://hdl.handle.net/10948/d1019699
- Description: Globally, organisations have recognised the strategic importance of knowledge management (KM) and are increasingly focusing their efforts on practices to foster the creation, sharing and integration of knowledge. Whilst most research in Knowledge Management (KM) has focused on the private sector, there is a breadth of potential applications of KM theory and practice for government agencies to adopt in search of resolving pertinent problems. The purpose of this study is to examine the factors that influence the effectiveness of knowledge management towards collaborative problem solving in government. What is missing is research-based evidence of the factors that influence the main factors for knowledge sharing across government agencies. Given this gap, the researcher addresses the research question: In government agencies mandated to resolve issues of crime, what are the key factors required which support and influence the collaborative sharing culture? Upon analysing the data, the researcher found the following key factors as being determinants on knowledge management: organisational culture, learning organisation, collaboration, subject matter experts and trust. The two factors – organisational culture and learning organisation were identified as the most significant factors which lay as the root or core for the ‘knowledge tree’. Once these roots are in place, the other factors will gain their significance on knowledge management. These findings serve to extend the findings of the existing literature within the government sector. This study is important because the findings provide government agencies with critically important information to guide their actions towards ensuring a knowledge sharing culture is embedded in government. Whilst the empirical findings do not focus on databases or information technology specifically, it is important to acknowledge the use of both technology and people. The main concern is with managing an organisation’s knowledge assets: creating, storing, protecting, disseminating and using mission-critical knowledge. When people need knowledge, is it the right knowledge and is it timely and easy to locate and access? Is this precious commodity updated as learning occurs and better ways of doing things are discovered? The awareness of the value of knowledge to a business, coupled with its leadership, acts as an integrator that improves cross- functional communication and cooperation. Shared knowledge not only makes for a more effective, efficient and agile organisation, but creates a common perspective and culture that produces a natural consistency of successful decisions and actions. The collaborative knowledge tree model proposed in this study uses the analogy of a tree when viewing South African government agencies as the branches of a collective tree (government). This ‘tree’ requires leaders and policy making to ‘dig deep’ into understanding the roots of the tree in order to ensure that the appropriate ‘seeds’ are planted such that the tree grows and is able to provide the necessary fruit required. Ultimately, as suggested by former President Thabo Mbeki (2012) in his address, the role of knowledge would thus be seen as a collaborative means towards the betterment of society.
- Full Text:
- Date Issued: 2012
- Authors: Mannie, Avain
- Date: 2012
- Subjects: Administrative agencies , Knowledge management , Business intelligence
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8822 , http://hdl.handle.net/10948/d1019699
- Description: Globally, organisations have recognised the strategic importance of knowledge management (KM) and are increasingly focusing their efforts on practices to foster the creation, sharing and integration of knowledge. Whilst most research in Knowledge Management (KM) has focused on the private sector, there is a breadth of potential applications of KM theory and practice for government agencies to adopt in search of resolving pertinent problems. The purpose of this study is to examine the factors that influence the effectiveness of knowledge management towards collaborative problem solving in government. What is missing is research-based evidence of the factors that influence the main factors for knowledge sharing across government agencies. Given this gap, the researcher addresses the research question: In government agencies mandated to resolve issues of crime, what are the key factors required which support and influence the collaborative sharing culture? Upon analysing the data, the researcher found the following key factors as being determinants on knowledge management: organisational culture, learning organisation, collaboration, subject matter experts and trust. The two factors – organisational culture and learning organisation were identified as the most significant factors which lay as the root or core for the ‘knowledge tree’. Once these roots are in place, the other factors will gain their significance on knowledge management. These findings serve to extend the findings of the existing literature within the government sector. This study is important because the findings provide government agencies with critically important information to guide their actions towards ensuring a knowledge sharing culture is embedded in government. Whilst the empirical findings do not focus on databases or information technology specifically, it is important to acknowledge the use of both technology and people. The main concern is with managing an organisation’s knowledge assets: creating, storing, protecting, disseminating and using mission-critical knowledge. When people need knowledge, is it the right knowledge and is it timely and easy to locate and access? Is this precious commodity updated as learning occurs and better ways of doing things are discovered? The awareness of the value of knowledge to a business, coupled with its leadership, acts as an integrator that improves cross- functional communication and cooperation. Shared knowledge not only makes for a more effective, efficient and agile organisation, but creates a common perspective and culture that produces a natural consistency of successful decisions and actions. The collaborative knowledge tree model proposed in this study uses the analogy of a tree when viewing South African government agencies as the branches of a collective tree (government). This ‘tree’ requires leaders and policy making to ‘dig deep’ into understanding the roots of the tree in order to ensure that the appropriate ‘seeds’ are planted such that the tree grows and is able to provide the necessary fruit required. Ultimately, as suggested by former President Thabo Mbeki (2012) in his address, the role of knowledge would thus be seen as a collaborative means towards the betterment of society.
- Full Text:
- Date Issued: 2012
Curriculum reform in Lesotho: exploring the interface between environmental education and geography in selected schools
- Authors: Raselimo, Mohaeka Gabriel
- Date: 2012
- Subjects: Curriculum planning -- Lesotho Curriculum change -- Lesotho Educational evaluation -- Lesotho Environmental education -- Study and teaching (Secondary) -- Lesotho Geography -- Study and teaching (Secondary) -- Lesotho Agenda 21 (Program)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1488 , http://hdl.handle.net/10962/d1003369
- Description: This study sought to explore the interface between environmental education (EE) and school geography with a view to understanding a process of curriculum reform in the context of Lesotho. The research was based on the curriculum reform process that was initiated by a Danish donor-funded project, known as the Lesotho Environmental Education Support Project (LEESP), which operated from 2001 to 2004. Driven by a sustainable development imperative, the project was intended to assist Lesotho in the implementation of local action for Agenda 21 by introducing environmental education into the formal education system. Deviating slightly from much published research on geographical and environmental education, which focuses on how geography contributes to environmental education, this study explored how the latter has shaped the former in terms of content and pedagogy. Using the lens of critical curriculum theory, I sought to understand the political nature of the curriculum and of curriculum change, focusing on the LEESP curriculum policy development, dissemination and implementation at classroom level. The study employed Bernstein's concepts of classification and framing to illuminate issues of power and control between discourses, and between teachers and learners. Operating within an interpretive qualitative research orientation, the study used a case study method focusing on five secondary/high schools in Lesotho. The data was generated through document analysis, interviews and classroom observations. The study examined the assumptions, values and ideologies underpinning environmental education curriculum intentions as reflected in LEESP documents. It also investigated the social process of conceptualising and disseminating environmental education to understand the challenges faced as education practitioners made sense of environmental education innovations in the specific contexts of Lesotho, and how these could possibly influence what happens at the classroom level. The analysis of the LEESP documents revealed that while there are many areas of synergy between the LEESP environmental education policy guidelines and the national education ideals in Lesotho, achievement of the transformational visions of action competence, which was the overarching concept in the reform process, would require major structural changes. The study also highlights issues of participation, contestations, tensions and contradictions associated with the conceptualisation and dissemination of environmental education. At implementation level, there is a disjuncture between environmental education policy intentions and practice. Geography teachers in the research schools generally understood the existence of environmental education in their schools in terms of environmental management. The findings also revealed that while there is generally a strong environmental dimension in geography content, as reflected in both curriculum materials and classroom practice, the subject still retains its disciplinary boundaries and makes little use of knowledge from other subjects or the everyday knowledge of the learners. Finally, it emerged that while the geography teachers in their rhetoric espoused learner-centred methods, in practice they generally employed traditional teacher-centred and book-centred methods. The study concludes that a lack of change in school geography in Lesotho, of the sort envisaged in LEESP, may be attributed to contextual and structural factors such as an overemphasis on examinations, and certain perceptions on the part of teachers and learners embedded in the history and culture of their society. A model of teacher professional development capable of supporting curriculum change is therefore proposed.
- Full Text:
- Date Issued: 2012
- Authors: Raselimo, Mohaeka Gabriel
- Date: 2012
- Subjects: Curriculum planning -- Lesotho Curriculum change -- Lesotho Educational evaluation -- Lesotho Environmental education -- Study and teaching (Secondary) -- Lesotho Geography -- Study and teaching (Secondary) -- Lesotho Agenda 21 (Program)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1488 , http://hdl.handle.net/10962/d1003369
- Description: This study sought to explore the interface between environmental education (EE) and school geography with a view to understanding a process of curriculum reform in the context of Lesotho. The research was based on the curriculum reform process that was initiated by a Danish donor-funded project, known as the Lesotho Environmental Education Support Project (LEESP), which operated from 2001 to 2004. Driven by a sustainable development imperative, the project was intended to assist Lesotho in the implementation of local action for Agenda 21 by introducing environmental education into the formal education system. Deviating slightly from much published research on geographical and environmental education, which focuses on how geography contributes to environmental education, this study explored how the latter has shaped the former in terms of content and pedagogy. Using the lens of critical curriculum theory, I sought to understand the political nature of the curriculum and of curriculum change, focusing on the LEESP curriculum policy development, dissemination and implementation at classroom level. The study employed Bernstein's concepts of classification and framing to illuminate issues of power and control between discourses, and between teachers and learners. Operating within an interpretive qualitative research orientation, the study used a case study method focusing on five secondary/high schools in Lesotho. The data was generated through document analysis, interviews and classroom observations. The study examined the assumptions, values and ideologies underpinning environmental education curriculum intentions as reflected in LEESP documents. It also investigated the social process of conceptualising and disseminating environmental education to understand the challenges faced as education practitioners made sense of environmental education innovations in the specific contexts of Lesotho, and how these could possibly influence what happens at the classroom level. The analysis of the LEESP documents revealed that while there are many areas of synergy between the LEESP environmental education policy guidelines and the national education ideals in Lesotho, achievement of the transformational visions of action competence, which was the overarching concept in the reform process, would require major structural changes. The study also highlights issues of participation, contestations, tensions and contradictions associated with the conceptualisation and dissemination of environmental education. At implementation level, there is a disjuncture between environmental education policy intentions and practice. Geography teachers in the research schools generally understood the existence of environmental education in their schools in terms of environmental management. The findings also revealed that while there is generally a strong environmental dimension in geography content, as reflected in both curriculum materials and classroom practice, the subject still retains its disciplinary boundaries and makes little use of knowledge from other subjects or the everyday knowledge of the learners. Finally, it emerged that while the geography teachers in their rhetoric espoused learner-centred methods, in practice they generally employed traditional teacher-centred and book-centred methods. The study concludes that a lack of change in school geography in Lesotho, of the sort envisaged in LEESP, may be attributed to contextual and structural factors such as an overemphasis on examinations, and certain perceptions on the part of teachers and learners embedded in the history and culture of their society. A model of teacher professional development capable of supporting curriculum change is therefore proposed.
- Full Text:
- Date Issued: 2012
Decentralised cooperative governance in the South African metropolitan municipalities
- Authors: Zimba, Anthony Andile
- Date: 2012
- Subjects: Community development -- South Africa , Local government -- South Africa , Intergovernmental cooperation -- South Africa , Public administration -- South Africa , Human services -- South Africa , Municipal government -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD (Social Science Dev)
- Identifier: vital:11427 , http://hdl.handle.net/10353/536 , Community development -- South Africa , Local government -- South Africa , Intergovernmental cooperation -- South Africa , Public administration -- South Africa , Human services -- South Africa , Municipal government -- South Africa
- Description: The study emanates from the constitutional imperatives with regard to the role of local government in community development. The notion of cooperative governance is envisaged in the South African Constitution which stipulates that all spheres of government must adhere to the principles of cooperative government and must conduct their activities within the parameters prescribed by the Constitution. The purpose is to support and strengthen the capacity of the local governments to manage their own affairs and to perform their functions. The basic values and principles governing public administration entail that: it must be broadly representative of the people of South Africa in order to redress the imbalances. The existing gaps in the legislation on decision making power at the local level of the municipality, be it in a ward committee or sub council, have not been adequately addressed in the post 1994 democratic dispensation. It is in this context that this study seeks to address these gaps and obstacles, and contribute to the design and development of a decentralized cooperative governance model, specifically to the six metropolitan municipalities and also provide a basis for further research. The findings of the research could be adapted as a national policy in the empowering of municipalities through the dispersal of democratic power which is an essential ingredient of inclusive governance. Based on a case study of six metropolitan municipalities, the research is intended to contribute to the development of empirically grounded; praxis and practical guideline in decentralized cooperative governance which can be adopted and institutionalized in public administration. It is believed that a study of decentralized cooperative governance adds value in that it seeks to link decentralized power and local development. Rather than civil society organisations being seen as adversarial, a creative partnership with the state in local development is crucial. This political assimilation is critical in the construction of democracy through fusing the substantive values of a political culture with the procedural requisites of democratic accountability. This serves to fragment and disperse political power and maintain a system of checks and balances with regard to the exercise of governmental power. The capacity for innovation, flexibility and change can be enhanced at the local level, and it is a cliché that local decision making is viewed as more democratic in contrast to central, top-down decision-making processes. A syncretistic model for local government based on the political adaptation of political and inclusive decentralisation is outlined.
- Full Text:
- Date Issued: 2012
- Authors: Zimba, Anthony Andile
- Date: 2012
- Subjects: Community development -- South Africa , Local government -- South Africa , Intergovernmental cooperation -- South Africa , Public administration -- South Africa , Human services -- South Africa , Municipal government -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD (Social Science Dev)
- Identifier: vital:11427 , http://hdl.handle.net/10353/536 , Community development -- South Africa , Local government -- South Africa , Intergovernmental cooperation -- South Africa , Public administration -- South Africa , Human services -- South Africa , Municipal government -- South Africa
- Description: The study emanates from the constitutional imperatives with regard to the role of local government in community development. The notion of cooperative governance is envisaged in the South African Constitution which stipulates that all spheres of government must adhere to the principles of cooperative government and must conduct their activities within the parameters prescribed by the Constitution. The purpose is to support and strengthen the capacity of the local governments to manage their own affairs and to perform their functions. The basic values and principles governing public administration entail that: it must be broadly representative of the people of South Africa in order to redress the imbalances. The existing gaps in the legislation on decision making power at the local level of the municipality, be it in a ward committee or sub council, have not been adequately addressed in the post 1994 democratic dispensation. It is in this context that this study seeks to address these gaps and obstacles, and contribute to the design and development of a decentralized cooperative governance model, specifically to the six metropolitan municipalities and also provide a basis for further research. The findings of the research could be adapted as a national policy in the empowering of municipalities through the dispersal of democratic power which is an essential ingredient of inclusive governance. Based on a case study of six metropolitan municipalities, the research is intended to contribute to the development of empirically grounded; praxis and practical guideline in decentralized cooperative governance which can be adopted and institutionalized in public administration. It is believed that a study of decentralized cooperative governance adds value in that it seeks to link decentralized power and local development. Rather than civil society organisations being seen as adversarial, a creative partnership with the state in local development is crucial. This political assimilation is critical in the construction of democracy through fusing the substantive values of a political culture with the procedural requisites of democratic accountability. This serves to fragment and disperse political power and maintain a system of checks and balances with regard to the exercise of governmental power. The capacity for innovation, flexibility and change can be enhanced at the local level, and it is a cliché that local decision making is viewed as more democratic in contrast to central, top-down decision-making processes. A syncretistic model for local government based on the political adaptation of political and inclusive decentralisation is outlined.
- Full Text:
- Date Issued: 2012
Deciding and doing what's right for people and planet : an investigation of the ethics-oriented learning of novice environmental educators
- Authors: Olvitt, Lausanne Laura
- Date: 2012
- Subjects: Environmental education Environmental ethics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1913 , http://hdl.handle.net/10962/d1007238
- Description: This study probes the ethics-oriented reflexive deliberations of three novice environmental education practitioners in South Africa. Two of the cases examined work in a local government context, and the third in an environmental non-governmental organisation context. All three practitioners are studying a one-year professional development course in environmental education. The research asks how their ethical deliberations ‘come to be what they are’, at the interface of their workplace and course-based learning processes. Working within a relational, social realist ontology, the study takes a sociocultural-historical approach to learning, development and social change. Cultural-historical activity theory (CHAT) provides theoretical tools and a descriptive language to approach the rich, qualitative data derived from workplace and course observations, extensive interviews, and document review. Critical discourse analysis was used as a secondary analytical tool to probe ethical and environmental discourses that were found to be influential in the course and workplace activity systems. Data from the three case studies was analysed in stages. In the first stage, CHAT provided a theoretical perspective and language of description to analyse the interacting activity systems in which each learner-practitioner’s ethics-oriented reflexive deliberations occurred. This provided a platform for the second stage of analysis which was framed by Margaret Archer’s (1995) social realist theory of morphogenesis/ morphostasis, followed by a summative retroductive analysis, to give an account of the interplay of historically-emergent social and cultural structures and individual reflexivity in relation to the ethical dimensions of environmental education practice. The study traces how ethics-oriented reflexive deliberations occur at the untidy, unpredictable intersection of workplace, course and personal contexts, and are strongest when they are situated in authentic contexts that resonate with learner-practitioners’ ‘ultimate concerns’ (after Archer, 2003; 2007). In this study, the learner-practitioners’ ‘ultimate concerns’ included family, personal well-being, social justice, cultural identity and religious commitments. The scope and depth of learner-practitioners’ social-ecological knowledge was also identified as a key factor influencing ethics-oriented reflexive deliberations, although the mediation of such knowledge can be hindered by language and conceptual ii barriers, amongst others. The study also noted how ethical positions circulating in the workplace, course and personal contexts were diverse, uneven and dynamic. Some ethical positions were found to be more explicitly differentiated than others, either resonating with or being overlooked by the learner-practitioners as they deliberated the ethical dimensions of their environmental education practice. In situations where there was limited depth, conceptual clarity and/ or confidence to engage directly with ethical concerns, there was a tendency towards (inadvertent) ethical relativism. Insights derived from the study suggest that these factors have limiting effects on the ethics-oriented reflexive deliberations of novice environmental educators. These insights point to the need for ethical deliberations to be re-personalised in context and underpinned by depth knowledge. A relational and pragmatic approach to environmental ethics (that recognises the validity of judgemental rationality – which can be fallible – and which seeks out practical adequacy) is put forward as appropriate and potentially generative in environmental education and training processes. This would need to be supported by careful attention to the influence of environmental discourses and practices in shaping ethical deliberations, and may also be helpful in developing a much-needed accessible, everyday language of ethical engagement. This study’s contribution to new knowledge in the field of environmental education is through its account of ethics-oriented reflexive deliberations emerging (in the Archerian morphogenetic sense) in complex, indeterminate ways at the interface of sociocultural and social-ecological contexts. The ethics-oriented reflexive deliberations of novice environmental educators occur in relation to their ‘ultimate concerns’ and are advanced or hindered by the historically-emergent practices, discourses and material realities of their workplace, personal and educational contexts. These insights require that the complex interplay of intersecting contexts and concerns that shape ethics-oriented reflexive deliberations be acknowledged and carefully mediated in both workplace-based and coursebased professional development processes.
- Full Text:
- Date Issued: 2012
- Authors: Olvitt, Lausanne Laura
- Date: 2012
- Subjects: Environmental education Environmental ethics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1913 , http://hdl.handle.net/10962/d1007238
- Description: This study probes the ethics-oriented reflexive deliberations of three novice environmental education practitioners in South Africa. Two of the cases examined work in a local government context, and the third in an environmental non-governmental organisation context. All three practitioners are studying a one-year professional development course in environmental education. The research asks how their ethical deliberations ‘come to be what they are’, at the interface of their workplace and course-based learning processes. Working within a relational, social realist ontology, the study takes a sociocultural-historical approach to learning, development and social change. Cultural-historical activity theory (CHAT) provides theoretical tools and a descriptive language to approach the rich, qualitative data derived from workplace and course observations, extensive interviews, and document review. Critical discourse analysis was used as a secondary analytical tool to probe ethical and environmental discourses that were found to be influential in the course and workplace activity systems. Data from the three case studies was analysed in stages. In the first stage, CHAT provided a theoretical perspective and language of description to analyse the interacting activity systems in which each learner-practitioner’s ethics-oriented reflexive deliberations occurred. This provided a platform for the second stage of analysis which was framed by Margaret Archer’s (1995) social realist theory of morphogenesis/ morphostasis, followed by a summative retroductive analysis, to give an account of the interplay of historically-emergent social and cultural structures and individual reflexivity in relation to the ethical dimensions of environmental education practice. The study traces how ethics-oriented reflexive deliberations occur at the untidy, unpredictable intersection of workplace, course and personal contexts, and are strongest when they are situated in authentic contexts that resonate with learner-practitioners’ ‘ultimate concerns’ (after Archer, 2003; 2007). In this study, the learner-practitioners’ ‘ultimate concerns’ included family, personal well-being, social justice, cultural identity and religious commitments. The scope and depth of learner-practitioners’ social-ecological knowledge was also identified as a key factor influencing ethics-oriented reflexive deliberations, although the mediation of such knowledge can be hindered by language and conceptual ii barriers, amongst others. The study also noted how ethical positions circulating in the workplace, course and personal contexts were diverse, uneven and dynamic. Some ethical positions were found to be more explicitly differentiated than others, either resonating with or being overlooked by the learner-practitioners as they deliberated the ethical dimensions of their environmental education practice. In situations where there was limited depth, conceptual clarity and/ or confidence to engage directly with ethical concerns, there was a tendency towards (inadvertent) ethical relativism. Insights derived from the study suggest that these factors have limiting effects on the ethics-oriented reflexive deliberations of novice environmental educators. These insights point to the need for ethical deliberations to be re-personalised in context and underpinned by depth knowledge. A relational and pragmatic approach to environmental ethics (that recognises the validity of judgemental rationality – which can be fallible – and which seeks out practical adequacy) is put forward as appropriate and potentially generative in environmental education and training processes. This would need to be supported by careful attention to the influence of environmental discourses and practices in shaping ethical deliberations, and may also be helpful in developing a much-needed accessible, everyday language of ethical engagement. This study’s contribution to new knowledge in the field of environmental education is through its account of ethics-oriented reflexive deliberations emerging (in the Archerian morphogenetic sense) in complex, indeterminate ways at the interface of sociocultural and social-ecological contexts. The ethics-oriented reflexive deliberations of novice environmental educators occur in relation to their ‘ultimate concerns’ and are advanced or hindered by the historically-emergent practices, discourses and material realities of their workplace, personal and educational contexts. These insights require that the complex interplay of intersecting contexts and concerns that shape ethics-oriented reflexive deliberations be acknowledged and carefully mediated in both workplace-based and coursebased professional development processes.
- Full Text:
- Date Issued: 2012
Designing a strategy to bring about a greater professional confidence for educators by improving their involvement in their own continous professional development
- Authors: Oosthuizen, Lizette Clarise
- Date: 2012
- Subjects: Teacher educators -- Professional relationships , Teachers -- Training of
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:9559 , http://hdl.handle.net/10948/d1012145 , Teacher educators -- Professional relationships , Teachers -- Training of
- Description: To ensure the professionalism of the teaching force, it is vital that the growing gap between the knowledge educators acquired during their years of training and emerging knowledge about teaching and education during their teaching careers be closed. The continuous professional development (CPD) of educators is a much-debated issue, the general consensus being that it is imperative that educators themselves become directly involved in their own CPD. School leadership should therefore establish what educators find meaningful and invest in CPD programmes that respond to their needs. Educator development is considered as productive when the educators are involved in planning, decision-making, implementation and evaluation around the CPD programmes offered to them. As an office-based educator responsible for educator development and training, educators‟ perceived lack of interest in their own CPD prompted me to investigate how their professional confidence could be boosted through improved involvement in their own CPD. The research question that underpinned this study was: What are the perceptions of educators in the Uitenhage area of their involvements in their own CPD and how to find a strategy to enhance their professional confidence through such involvement? This study adopted the interpretive research paradigm, as the aim was to understand how educators understood their involvement in their own CPD. The qualitative research methods employed, allowed me to share the experiences of my participants. The research sample consisted of Integrated Quality Management Systems (IQMS) coordinators, as members of the school development team (SDT) responsible for educator development, from twelve primary schools in the Uitenhage District. In Phase 1 of the study, data were collected through questionnaires as well as individual and group interviews. Phase 2 consisted of a workshop for the participants, focusing on the key issues identified from the completed questionnaires and interviews. From the data analysis, five themes emerged, namely the contribution by the school, school management team (SMT), Department of Education (DoE) in the educators‟ CPD; the role of the individual educator in his/her own CPD; the factors influencing the effective implementation of educators‟ CPD; the skills and competencies that educators need to acquire through CPD; and the role of the IQMS process in the CPD of educators. Based on the research findings, a strategy was designed to guide educators to increase their professional confidence through improved involvement in their own CPD. Specific recommendations were formulated, such as that adequate time should be allocated for the CPD of educators; school leadership should make a concerted effort to motivate educators to become involved in CPD programmes; and educators should be encouraged to learn collaboratively through their involvement in communities of learning. The conclusions from this research are that educators should be life-long learners, actively involved in their own CPD and that schools, SMTs and the DoE should assist them by providing the necessary support, resources and guidance through enabling conditions conducive to a culture of learning.
- Full Text:
- Date Issued: 2012
- Authors: Oosthuizen, Lizette Clarise
- Date: 2012
- Subjects: Teacher educators -- Professional relationships , Teachers -- Training of
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:9559 , http://hdl.handle.net/10948/d1012145 , Teacher educators -- Professional relationships , Teachers -- Training of
- Description: To ensure the professionalism of the teaching force, it is vital that the growing gap between the knowledge educators acquired during their years of training and emerging knowledge about teaching and education during their teaching careers be closed. The continuous professional development (CPD) of educators is a much-debated issue, the general consensus being that it is imperative that educators themselves become directly involved in their own CPD. School leadership should therefore establish what educators find meaningful and invest in CPD programmes that respond to their needs. Educator development is considered as productive when the educators are involved in planning, decision-making, implementation and evaluation around the CPD programmes offered to them. As an office-based educator responsible for educator development and training, educators‟ perceived lack of interest in their own CPD prompted me to investigate how their professional confidence could be boosted through improved involvement in their own CPD. The research question that underpinned this study was: What are the perceptions of educators in the Uitenhage area of their involvements in their own CPD and how to find a strategy to enhance their professional confidence through such involvement? This study adopted the interpretive research paradigm, as the aim was to understand how educators understood their involvement in their own CPD. The qualitative research methods employed, allowed me to share the experiences of my participants. The research sample consisted of Integrated Quality Management Systems (IQMS) coordinators, as members of the school development team (SDT) responsible for educator development, from twelve primary schools in the Uitenhage District. In Phase 1 of the study, data were collected through questionnaires as well as individual and group interviews. Phase 2 consisted of a workshop for the participants, focusing on the key issues identified from the completed questionnaires and interviews. From the data analysis, five themes emerged, namely the contribution by the school, school management team (SMT), Department of Education (DoE) in the educators‟ CPD; the role of the individual educator in his/her own CPD; the factors influencing the effective implementation of educators‟ CPD; the skills and competencies that educators need to acquire through CPD; and the role of the IQMS process in the CPD of educators. Based on the research findings, a strategy was designed to guide educators to increase their professional confidence through improved involvement in their own CPD. Specific recommendations were formulated, such as that adequate time should be allocated for the CPD of educators; school leadership should make a concerted effort to motivate educators to become involved in CPD programmes; and educators should be encouraged to learn collaboratively through their involvement in communities of learning. The conclusions from this research are that educators should be life-long learners, actively involved in their own CPD and that schools, SMTs and the DoE should assist them by providing the necessary support, resources and guidance through enabling conditions conducive to a culture of learning.
- Full Text:
- Date Issued: 2012
Determinants of customer satisfaction and retention: a survey of the banking industry in Kenya
- Authors: Mburu, Peris Njoki
- Date: 2012
- Subjects: Banks and banking -- Customer services -- Kenya , Consumer satisfaction -- Banks and banking -- Kenya , Customer relations -- Management -- Kenya
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8787 , http://hdl.handle.net/10948/d1014106
- Description: Customers have become the lifeblood of any organisation. Without customers, or-ganisations would not exist let alone survive in this competitive global environment (Grigoroudis, Politis and Siskos, 2002). Banks depend on sufficient and sustaining profitability to survive in the global business world. Customers are the source of banks‟ profitability. By satisfying the customer, the bank is able to retain the custom-er and reap maximum benefits from the relationship which ultimately leads to higher profitability. Customer satisfaction has therefore evolved as a strategic business ini-tiative which banks cannot ignore. Retention of the bank customer has become one of the most important objectives of the overall marketing strategy of any bank. In Kenya, the term „customer service‟ came to the fore just over fifteen years ago when banks started acquiring customer service departments. Since then, many cus-tomer training programs for staff have been put in place to transform the image of the customer as not just a profit-maker for the banks but as a human being with needs, which if not fulfilled will cause the customer to look for alternatives in the market. Training has focused on the bank staff whose customer handling skills have been sharpened. In spite of this, no empirical study has attempted to find out if the intended satisfaction of the customer has been achieved or not, which is indicative of little or no attention being given to this important phenomenon. In Africa, with the ex-ception of South Africa, empirical studies on customer satisfaction in the banking in-dustry are few. This gap presented the motivation for this study. The primary objective was to establish the determinants of customer satisfaction and retention in the Kenyan banking industry. The secondary objectives were to establish the relationship between socio-economic factors and customer satisfaction in Ken-yan banks; secondly, to determine whether bank-related factors influence customer satisfaction in Kenyan banks; thirdly, to identify the various strategies known to cus-tomers and employed by Kenyan banks to ensure customer satisfaction and customer retention and finally, to analyse the relationship between customer satisfaction and customer retention in Kenyan banks. The study adopted a descriptive survey design to suit the target population which was dispersed over a wide geographical region spanning the entire Kenya. The tar-get population included every bank customer in Kenya. Both qualitative and quantita-tive data were used. The data collection instrument was a self-administered ques-tionnaire that contained both closed and open-ended questions. Statistical tests were done using Pearson, Chi Square, Anova, Pearson Correlation and Multi-linear re-gression. Data were presented using frequency distribution tables, percentages, cross tabulation and pie charts. The findings indicated a positive relationship be-tween bank-related factors and customer satisfaction and retention. The conclusion was that if banks improved on factors like quality service, staff orientation towards customers, availability of management and ATM uptimes just to name a few, propor-tionately, customer satisfaction and retention would be enhanced. Finally, recommendations based on the findings were made to the Kenyan banks highlighting antecedents which would enhance the customers‟ satisfaction and reten-tion in the Kenyan banking industry.
- Full Text:
- Date Issued: 2012
- Authors: Mburu, Peris Njoki
- Date: 2012
- Subjects: Banks and banking -- Customer services -- Kenya , Consumer satisfaction -- Banks and banking -- Kenya , Customer relations -- Management -- Kenya
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8787 , http://hdl.handle.net/10948/d1014106
- Description: Customers have become the lifeblood of any organisation. Without customers, or-ganisations would not exist let alone survive in this competitive global environment (Grigoroudis, Politis and Siskos, 2002). Banks depend on sufficient and sustaining profitability to survive in the global business world. Customers are the source of banks‟ profitability. By satisfying the customer, the bank is able to retain the custom-er and reap maximum benefits from the relationship which ultimately leads to higher profitability. Customer satisfaction has therefore evolved as a strategic business ini-tiative which banks cannot ignore. Retention of the bank customer has become one of the most important objectives of the overall marketing strategy of any bank. In Kenya, the term „customer service‟ came to the fore just over fifteen years ago when banks started acquiring customer service departments. Since then, many cus-tomer training programs for staff have been put in place to transform the image of the customer as not just a profit-maker for the banks but as a human being with needs, which if not fulfilled will cause the customer to look for alternatives in the market. Training has focused on the bank staff whose customer handling skills have been sharpened. In spite of this, no empirical study has attempted to find out if the intended satisfaction of the customer has been achieved or not, which is indicative of little or no attention being given to this important phenomenon. In Africa, with the ex-ception of South Africa, empirical studies on customer satisfaction in the banking in-dustry are few. This gap presented the motivation for this study. The primary objective was to establish the determinants of customer satisfaction and retention in the Kenyan banking industry. The secondary objectives were to establish the relationship between socio-economic factors and customer satisfaction in Ken-yan banks; secondly, to determine whether bank-related factors influence customer satisfaction in Kenyan banks; thirdly, to identify the various strategies known to cus-tomers and employed by Kenyan banks to ensure customer satisfaction and customer retention and finally, to analyse the relationship between customer satisfaction and customer retention in Kenyan banks. The study adopted a descriptive survey design to suit the target population which was dispersed over a wide geographical region spanning the entire Kenya. The tar-get population included every bank customer in Kenya. Both qualitative and quantita-tive data were used. The data collection instrument was a self-administered ques-tionnaire that contained both closed and open-ended questions. Statistical tests were done using Pearson, Chi Square, Anova, Pearson Correlation and Multi-linear re-gression. Data were presented using frequency distribution tables, percentages, cross tabulation and pie charts. The findings indicated a positive relationship be-tween bank-related factors and customer satisfaction and retention. The conclusion was that if banks improved on factors like quality service, staff orientation towards customers, availability of management and ATM uptimes just to name a few, propor-tionately, customer satisfaction and retention would be enhanced. Finally, recommendations based on the findings were made to the Kenyan banks highlighting antecedents which would enhance the customers‟ satisfaction and reten-tion in the Kenyan banking industry.
- Full Text:
- Date Issued: 2012
Development of a hydraulic sub-model as part of a desktop environmental flow assessment method
- Authors: Desai, Ahmed Yacoob
- Date: 2012
- Subjects: Hydrologic models -- Research -- South Africa Hydraulic engineering -- South Africa Rivers -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6041 , http://hdl.handle.net/10962/d1006200
- Description: Countries around the world have been developing ecological policies to protect their water resources and minimise the impacts of development on their river systems. The concept of ‘minimum flows’ was initially established as a solution but it did not provide sufficient protection as all elements of a flow regime were found to be important for the protection of the river ecosystem. “Environmental flows” were developed to determine these flow regimes to maintain a river in some defined ecological condition. Rapid, initial estimates of the quantity component of environmental flows may be determined using the Desktop Reserve Model in South Africa. However, the Desktop Reserve Model is dependent upon the characteristics of the reference natural hydrology used. The advancements in hydraulic and ecological relationships from the past decade have prompted the development of a Revised Desktop Reserve Model (RDRM) that would incorporate these relationships. The research in this thesis presents the development of the hydraulic sub-model for the RDRM. The hydraulic sub-model was designed to produce a realistic representation of the hydraulic conditions using hydraulic parameters/characteristics from readily available information for any part of South Africa. Hydraulic data from past EWR studies were used to estimate the hydraulic parameters. These estimated hydraulic parameters were used to develop hydraulic estimation relationships and these relationships were developed based on a combination of regression and rule-based procedures. The estimation relationships were incorporated into the hydraulic sub-model of the integrated RDRM and assessments of the hydraulic outputs and EWR results were undertaken to assess the ‘applicability’ of the hydraulic sub-model. The hydraulic sub-model was assessed to be at a stage where it can satisfactorily be incorporated in the RDRM and that it is adequately robust in many situations. Recommendations for future work include the refinement of estimation of the channel forming discharge or the use of spatial imagery to check the maximum channel width estimation. It is also proposed that a future version of the hydraulic sub-model could include flow regime change impacts on channel geomorphology and sedimentology so that flow management scenarios can be more effectively assessed.
- Full Text:
- Date Issued: 2012
- Authors: Desai, Ahmed Yacoob
- Date: 2012
- Subjects: Hydrologic models -- Research -- South Africa Hydraulic engineering -- South Africa Rivers -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6041 , http://hdl.handle.net/10962/d1006200
- Description: Countries around the world have been developing ecological policies to protect their water resources and minimise the impacts of development on their river systems. The concept of ‘minimum flows’ was initially established as a solution but it did not provide sufficient protection as all elements of a flow regime were found to be important for the protection of the river ecosystem. “Environmental flows” were developed to determine these flow regimes to maintain a river in some defined ecological condition. Rapid, initial estimates of the quantity component of environmental flows may be determined using the Desktop Reserve Model in South Africa. However, the Desktop Reserve Model is dependent upon the characteristics of the reference natural hydrology used. The advancements in hydraulic and ecological relationships from the past decade have prompted the development of a Revised Desktop Reserve Model (RDRM) that would incorporate these relationships. The research in this thesis presents the development of the hydraulic sub-model for the RDRM. The hydraulic sub-model was designed to produce a realistic representation of the hydraulic conditions using hydraulic parameters/characteristics from readily available information for any part of South Africa. Hydraulic data from past EWR studies were used to estimate the hydraulic parameters. These estimated hydraulic parameters were used to develop hydraulic estimation relationships and these relationships were developed based on a combination of regression and rule-based procedures. The estimation relationships were incorporated into the hydraulic sub-model of the integrated RDRM and assessments of the hydraulic outputs and EWR results were undertaken to assess the ‘applicability’ of the hydraulic sub-model. The hydraulic sub-model was assessed to be at a stage where it can satisfactorily be incorporated in the RDRM and that it is adequately robust in many situations. Recommendations for future work include the refinement of estimation of the channel forming discharge or the use of spatial imagery to check the maximum channel width estimation. It is also proposed that a future version of the hydraulic sub-model could include flow regime change impacts on channel geomorphology and sedimentology so that flow management scenarios can be more effectively assessed.
- Full Text:
- Date Issued: 2012
Development of a value based pricing index for new drugs in metastatic colorectal cancer
- Authors: Dranitsaris, George
- Date: 2012
- Subjects: Drug -- Prices , Prescription pricing , Pharmaceutical industry -- Prices
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10140 , http://hdl.handle.net/10948/d1009310 , Drug -- Prices , Prescription pricing , Pharmaceutical industry -- Prices
- Description: Background: Worldwide, prices for cancer drugs have been under downward pressure where several governments have mandated price cuts of branded and generic products. A better alternative to mandated price cuts would be the estimation of a launch price based on drug performance, cost effectiveness and a country’s ability to pay. In this study, the development of a global pricing index for new drugs that encompasses all of these attributes in patients with metastatic colorectal cancer (mCRC) is described. Methods: A pharmacoeconomic model was developed to simulate clinical outcomes in mCRC patients receiving chemotherapy with the addition of a “new drug” that improves survival by 1.4, 3 and 6 months. Cost and health state utility data were obtained from cancer centers and oncology nurses (total n=112) in Canada (n=24), Spain (n=24), India (n=24), South Africa (n=16) and Malaysia (n=24). A price per dose was estimated for each survival increment using a target value threshold of three times the per capita gross domestic product (GDP) for each country, as recommended by the World Health Organisation (WHO). Multivariable analysis was then used to develop the pricing index, which considers survival benefit, per capita GDP and income dispersion as measured by the Gini coefficient as predictor variables. Results: Higher survival benefits were associated with elevated drug prices, especially in wealthier countries such as Canada and Spain. For a nation like Argentina with a per capita GDP of $15,000 and a Gini coefficient of 51, it is estimated that for a drug which provides a 4 month survival benefit in mCRC, the value based price would be $US 630 per dose. In contrast, the same drug in a wealthier country like Norway could command a price of $US 2,775 and still be considered cost effective according to the WHO criteria. Conclusions: A global pricing index was presented that can be used to estimate a value based price in different countries for new drugs in mCRC. The application of this index to estimate a price based on cost effectiveness would be a good starting point for opening dialogue between the key stakeholders and a better alternative to governments’ mandated price cuts.
- Full Text:
- Date Issued: 2012
- Authors: Dranitsaris, George
- Date: 2012
- Subjects: Drug -- Prices , Prescription pricing , Pharmaceutical industry -- Prices
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10140 , http://hdl.handle.net/10948/d1009310 , Drug -- Prices , Prescription pricing , Pharmaceutical industry -- Prices
- Description: Background: Worldwide, prices for cancer drugs have been under downward pressure where several governments have mandated price cuts of branded and generic products. A better alternative to mandated price cuts would be the estimation of a launch price based on drug performance, cost effectiveness and a country’s ability to pay. In this study, the development of a global pricing index for new drugs that encompasses all of these attributes in patients with metastatic colorectal cancer (mCRC) is described. Methods: A pharmacoeconomic model was developed to simulate clinical outcomes in mCRC patients receiving chemotherapy with the addition of a “new drug” that improves survival by 1.4, 3 and 6 months. Cost and health state utility data were obtained from cancer centers and oncology nurses (total n=112) in Canada (n=24), Spain (n=24), India (n=24), South Africa (n=16) and Malaysia (n=24). A price per dose was estimated for each survival increment using a target value threshold of three times the per capita gross domestic product (GDP) for each country, as recommended by the World Health Organisation (WHO). Multivariable analysis was then used to develop the pricing index, which considers survival benefit, per capita GDP and income dispersion as measured by the Gini coefficient as predictor variables. Results: Higher survival benefits were associated with elevated drug prices, especially in wealthier countries such as Canada and Spain. For a nation like Argentina with a per capita GDP of $15,000 and a Gini coefficient of 51, it is estimated that for a drug which provides a 4 month survival benefit in mCRC, the value based price would be $US 630 per dose. In contrast, the same drug in a wealthier country like Norway could command a price of $US 2,775 and still be considered cost effective according to the WHO criteria. Conclusions: A global pricing index was presented that can be used to estimate a value based price in different countries for new drugs in mCRC. The application of this index to estimate a price based on cost effectiveness would be a good starting point for opening dialogue between the key stakeholders and a better alternative to governments’ mandated price cuts.
- Full Text:
- Date Issued: 2012
Development of corona-based power supplies for remote repeater stations for overhead HVDC power transmission systems
- Authors: Kaseke, R
- Date: 2012
- Language: English
- Type: Thesis , Doctoral , PhD (Physics)
- Identifier: vital:11595 , http://hdl.handle.net/10353/d1006787
- Description: More and more people worldwide are becoming “carbon conscious”. This means they are becoming increasingly aware of the imminent adverse effects of global warming. Of late there has been an urgent drive for governments to be on the forefront of all carbon mitigation initiatives. One such drive involves the United Nations Framework Convention on Climate Change whose parties have been meeting regularly under the banner of Conference of Parties (COP) since 1995. At this conference, parties to the convention review progress made in dealing with climate change. Also key to the deliberations in such meetings are better ways of developing cleaner “carbon free” energy sources. Energy sources of this nature are commonly known as renewable energy sources. In essence global energy trends are constantly moving towards development of more renewable energy sources. It is an undeniable fact that some of viable renewable energy sources especially those with bulk capacity are usually located remotely from load centers. This inevitable reality necessitates the construction of long distance bulk power transmission corridors to link generation sites with load centers. Due to its many inherent advantages over High Voltage Alternate Current (HVAC) for long distance power transmission, High Voltage Direct Current (HVDC) is gradually winning the favor of many utilities. In fact, recent advances in HVDC technology have encouraged many utilities to explore the possibility of harnessing remotely located renewable energy sources which would have otherwise not been viable with HVAC transmission. Through the unfortunate and inevitable phenomenon known as corona effect, overhead HVDC conductors suffer real power losses to the air dielectric surrounding them. Through corona, part of the energy carried on the transmission line is expended through ionization and movement of charges in the air dielectric. This study combined physics, mathematical as well engineering concepts to review corona phenomenon around HVDC lines with specific emphasis on space charge generation and motion within ionized DC fields as well as the influence of temperature on corona discharge or power loss. Also, unlike HVAC, performance of an HVDC system relies heavily on the availability of a reliable and robust telecommunication system. One of the key ways of ensuring reliability of a telecommunication system is by making sure that reliable power supplies are in place to power remote repeater stations. A novel concept of quasi-autonomous corona-based power supply (or QC power supply in short) that works on the principle of magnetohydrodymic (MHD) power generation was developed. A small scale experiment was then designed to assess the feasibility of such power supplies. The experiment was conducted with DC supply of a maximum rated voltage of 30 kVDC and generated up to 6 VDC at an optimum ambient temperature of 23°C. These results have confirmed that with further development QC power supplies have the potential of proving reliable power to remotely located repeaters or any other small critical loads along the stretch of the HVDC transmission line. Practical HVDC transmission systems operate voltages in the excess of 500 kV. By linear extrapolation of the above mentioned results; one would expect to yield up to 100-, 120- and 160-VDC from a 500-, 600- and 800- kV HVDC system, respectively. Although the study succeeded in conceptualizing a CMHD idea upon which the novel QC power supply was developed, quite extensive and rigorous design, modeling, prototyping and experimentation processes are still required before the first QC power supply can be commissioned on a practical HVDC line
- Full Text:
- Date Issued: 2012
- Authors: Kaseke, R
- Date: 2012
- Language: English
- Type: Thesis , Doctoral , PhD (Physics)
- Identifier: vital:11595 , http://hdl.handle.net/10353/d1006787
- Description: More and more people worldwide are becoming “carbon conscious”. This means they are becoming increasingly aware of the imminent adverse effects of global warming. Of late there has been an urgent drive for governments to be on the forefront of all carbon mitigation initiatives. One such drive involves the United Nations Framework Convention on Climate Change whose parties have been meeting regularly under the banner of Conference of Parties (COP) since 1995. At this conference, parties to the convention review progress made in dealing with climate change. Also key to the deliberations in such meetings are better ways of developing cleaner “carbon free” energy sources. Energy sources of this nature are commonly known as renewable energy sources. In essence global energy trends are constantly moving towards development of more renewable energy sources. It is an undeniable fact that some of viable renewable energy sources especially those with bulk capacity are usually located remotely from load centers. This inevitable reality necessitates the construction of long distance bulk power transmission corridors to link generation sites with load centers. Due to its many inherent advantages over High Voltage Alternate Current (HVAC) for long distance power transmission, High Voltage Direct Current (HVDC) is gradually winning the favor of many utilities. In fact, recent advances in HVDC technology have encouraged many utilities to explore the possibility of harnessing remotely located renewable energy sources which would have otherwise not been viable with HVAC transmission. Through the unfortunate and inevitable phenomenon known as corona effect, overhead HVDC conductors suffer real power losses to the air dielectric surrounding them. Through corona, part of the energy carried on the transmission line is expended through ionization and movement of charges in the air dielectric. This study combined physics, mathematical as well engineering concepts to review corona phenomenon around HVDC lines with specific emphasis on space charge generation and motion within ionized DC fields as well as the influence of temperature on corona discharge or power loss. Also, unlike HVAC, performance of an HVDC system relies heavily on the availability of a reliable and robust telecommunication system. One of the key ways of ensuring reliability of a telecommunication system is by making sure that reliable power supplies are in place to power remote repeater stations. A novel concept of quasi-autonomous corona-based power supply (or QC power supply in short) that works on the principle of magnetohydrodymic (MHD) power generation was developed. A small scale experiment was then designed to assess the feasibility of such power supplies. The experiment was conducted with DC supply of a maximum rated voltage of 30 kVDC and generated up to 6 VDC at an optimum ambient temperature of 23°C. These results have confirmed that with further development QC power supplies have the potential of proving reliable power to remotely located repeaters or any other small critical loads along the stretch of the HVDC transmission line. Practical HVDC transmission systems operate voltages in the excess of 500 kV. By linear extrapolation of the above mentioned results; one would expect to yield up to 100-, 120- and 160-VDC from a 500-, 600- and 800- kV HVDC system, respectively. Although the study succeeded in conceptualizing a CMHD idea upon which the novel QC power supply was developed, quite extensive and rigorous design, modeling, prototyping and experimentation processes are still required before the first QC power supply can be commissioned on a practical HVDC line
- Full Text:
- Date Issued: 2012
Development of molecularly imprinted polymer based solid phase extraction sorbents for the selective cleanup of food and pharmaceutical residue samples
- Authors: Batlokwa, Bareki Shima
- Date: 2012
- Subjects: Sorbents -- Research Nanofibers -- Research Aflatoxins -- Research Electrospinning -- Research Extraction (Chemistry) -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4309 , http://hdl.handle.net/10962/d1004967
- Description: This thesis presents the development of chlorophyll, cholic acid, aflatoxin B1 molecularly imprinted polymer (MIP) particles and cholic acid MIP nanofibers for application as selective solid phase extraction (SPE) sorbents. The particles were prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The AFB1 MIP particles were compared with an aflatoxin specific immunoextraction sorbent in cleaning-up and pre-concentrating aflatoxins from nut extracts. They both recorded high extraction efficiencies (EEs) of > 97 % in selectively extracting the aflatoxins (AFB1, AFB2, AFG1 and AFG2). High reproducibility marked by the low %RSDs of < 1% and low LODs of ≤ 0.02 ng/g were calculated in all cases. The LODs were within the monitoring requirements of the European Commission. The results were validated with a peanut butter certified reference material. The chlorophyll MIP on the other hand selectively removed chlorophyll that would otherwise interfere during pesticide residue analysis (PRA) from > 0.6 to <0.09 Au in green plants extracts. The extracted chlorophyll was removed to far below the level of ≥ 0.399 Au that is usually associated with interference during PRA. Furthermore, the MIP demonstrated better selectivity by removing only chlorophyll (> 99%) in the presence of planar pesticides than the currently employed graphitized carbon black (GCB) that removed both the chlorophyll (> 88%) and planar pesticides (> 89%). For the interfering cholic acid during drug residue analysis, cholic acid MIP electrospun nanofibers demonstrated to be more sensitive and possessing higher loading capacity than the MIP particles. 100% cholic acid was removed by the nanofibers from standard solutions relative to 80% by the particles. This showed that the nanofibers have better performance than the micro particles and as such have potential to replace the particle based SPE sorbents that are currently in use. All the templates were optimally removed from the prepared MIPs by employing a novel pressurized hot water extraction template removal method that was used for the first time in this thesis. The method employed only water, an environmentally friendly solvent to remove templates to ≥ 99.6% with template residual bleeding of ≤ 0.02%.
- Full Text:
- Date Issued: 2012
- Authors: Batlokwa, Bareki Shima
- Date: 2012
- Subjects: Sorbents -- Research Nanofibers -- Research Aflatoxins -- Research Electrospinning -- Research Extraction (Chemistry) -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4309 , http://hdl.handle.net/10962/d1004967
- Description: This thesis presents the development of chlorophyll, cholic acid, aflatoxin B1 molecularly imprinted polymer (MIP) particles and cholic acid MIP nanofibers for application as selective solid phase extraction (SPE) sorbents. The particles were prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The AFB1 MIP particles were compared with an aflatoxin specific immunoextraction sorbent in cleaning-up and pre-concentrating aflatoxins from nut extracts. They both recorded high extraction efficiencies (EEs) of > 97 % in selectively extracting the aflatoxins (AFB1, AFB2, AFG1 and AFG2). High reproducibility marked by the low %RSDs of < 1% and low LODs of ≤ 0.02 ng/g were calculated in all cases. The LODs were within the monitoring requirements of the European Commission. The results were validated with a peanut butter certified reference material. The chlorophyll MIP on the other hand selectively removed chlorophyll that would otherwise interfere during pesticide residue analysis (PRA) from > 0.6 to <0.09 Au in green plants extracts. The extracted chlorophyll was removed to far below the level of ≥ 0.399 Au that is usually associated with interference during PRA. Furthermore, the MIP demonstrated better selectivity by removing only chlorophyll (> 99%) in the presence of planar pesticides than the currently employed graphitized carbon black (GCB) that removed both the chlorophyll (> 88%) and planar pesticides (> 89%). For the interfering cholic acid during drug residue analysis, cholic acid MIP electrospun nanofibers demonstrated to be more sensitive and possessing higher loading capacity than the MIP particles. 100% cholic acid was removed by the nanofibers from standard solutions relative to 80% by the particles. This showed that the nanofibers have better performance than the micro particles and as such have potential to replace the particle based SPE sorbents that are currently in use. All the templates were optimally removed from the prepared MIPs by employing a novel pressurized hot water extraction template removal method that was used for the first time in this thesis. The method employed only water, an environmentally friendly solvent to remove templates to ≥ 99.6% with template residual bleeding of ≤ 0.02%.
- Full Text:
- Date Issued: 2012
Dreams, sexuality and fantasy: a psychoanalytic reading of K. Sello Duiker’s novels
- Authors: Kirton-Els, Teneille
- Date: 2012
- Language: English
- Type: Thesis , Doctoral , DLitt et Phil
- Identifier: vital:11890 , http://hdl.handle.net/10353/d1020154
- Description: The primary aim of this thesis is to provide a text-based literary study exploring the characters and themes created by K. Sello Duiker in the three novels, Thirteen Cents, The Quiet Violence of Dreams and The Hidden Star. Duiker’s work is significant because it highlights prominent societal challenges prevalent in post-apartheid society. By analysing Duiker’s novels one acquires a better understanding of this author, an understanding of the world that contributed to the creation of his texts and his contribution to South African literature. Insight into Duiker’s fictional world allows for a careful investigation of the prominent societal issues prevalent in Duiker’s work - a world riddled with violence, issues of sexuality and psychological distress. For this purpose this thesis is premised on the notion that underpinning K. Sello Duiker’s oeuvre is a central focus on dreams, sexuality and fantasy. Logically, therefore, the main focus of the study is specifically on the inner working of the characters’ minds and how they deal/ or are unable to cope with contemporary social concerns, often resulting in psychological turmoil and dysfunctionality. For this reason, prominent themes examined in this study are the interpretation of dreams, an exploration of sexuality and an examination of fantasy in the three novels. Psychoanalytic literary theory, with the main focus being specifically on the theories presented by Sigmund Freud is used as an analytic tool to read Duiker’s texts. Psychoanalytic theory is arguably the most appropriate for analysing Duiker’s novels as it allows one to investigate the characters’ psyches and the psychological effect of societal influences on these characters. In addition, one is also able to examine how the characters are able/ unable to deal with the trauma caused by the contemporary issues in society – issues of violence, sexuality and psychological distress. Thus, one is able to grasp an overall understanding of the characters’ behaviour and actions. Furthermore, the characters’ experiences are based on the behaviour and incidents of real people, people suffering from psychological dysfunctionality, sexuality issues and identity crisis. The first chapter discusses post-apartheid literature, and provides a brief background on Duiker, his works and his conception as a writer. Chapter two provides an overview of psychoanalytic theory and on the relevant theories of Sigmund Freud. Chapter three offers a reading of Thirteen Cents, a novel that pays particular attention to the lives of children living on the streets of Cape Town. In the next chapter The Quiet Violence of Dreams is examined with a special focus on Duiker’s experimentation with form in the construction of this novel. Aspects pertaining to sexuality and dreams are also examined. Chapter five pays particular attention to magical realism and fantasy in The Hidden Star.
- Full Text:
- Date Issued: 2012
- Authors: Kirton-Els, Teneille
- Date: 2012
- Language: English
- Type: Thesis , Doctoral , DLitt et Phil
- Identifier: vital:11890 , http://hdl.handle.net/10353/d1020154
- Description: The primary aim of this thesis is to provide a text-based literary study exploring the characters and themes created by K. Sello Duiker in the three novels, Thirteen Cents, The Quiet Violence of Dreams and The Hidden Star. Duiker’s work is significant because it highlights prominent societal challenges prevalent in post-apartheid society. By analysing Duiker’s novels one acquires a better understanding of this author, an understanding of the world that contributed to the creation of his texts and his contribution to South African literature. Insight into Duiker’s fictional world allows for a careful investigation of the prominent societal issues prevalent in Duiker’s work - a world riddled with violence, issues of sexuality and psychological distress. For this purpose this thesis is premised on the notion that underpinning K. Sello Duiker’s oeuvre is a central focus on dreams, sexuality and fantasy. Logically, therefore, the main focus of the study is specifically on the inner working of the characters’ minds and how they deal/ or are unable to cope with contemporary social concerns, often resulting in psychological turmoil and dysfunctionality. For this reason, prominent themes examined in this study are the interpretation of dreams, an exploration of sexuality and an examination of fantasy in the three novels. Psychoanalytic literary theory, with the main focus being specifically on the theories presented by Sigmund Freud is used as an analytic tool to read Duiker’s texts. Psychoanalytic theory is arguably the most appropriate for analysing Duiker’s novels as it allows one to investigate the characters’ psyches and the psychological effect of societal influences on these characters. In addition, one is also able to examine how the characters are able/ unable to deal with the trauma caused by the contemporary issues in society – issues of violence, sexuality and psychological distress. Thus, one is able to grasp an overall understanding of the characters’ behaviour and actions. Furthermore, the characters’ experiences are based on the behaviour and incidents of real people, people suffering from psychological dysfunctionality, sexuality issues and identity crisis. The first chapter discusses post-apartheid literature, and provides a brief background on Duiker, his works and his conception as a writer. Chapter two provides an overview of psychoanalytic theory and on the relevant theories of Sigmund Freud. Chapter three offers a reading of Thirteen Cents, a novel that pays particular attention to the lives of children living on the streets of Cape Town. In the next chapter The Quiet Violence of Dreams is examined with a special focus on Duiker’s experimentation with form in the construction of this novel. Aspects pertaining to sexuality and dreams are also examined. Chapter five pays particular attention to magical realism and fantasy in The Hidden Star.
- Full Text:
- Date Issued: 2012