Metabolic effects brought about by tricyclic antidepressants and the contribution of a medicinal plant in alleviating high fat diet induced insulin resistance in male wistar rats
- Authors: Chadwick, Wayne
- Date: 2006
- Subjects: Rats -- Metabolism , Diabetes -- Research , Medicinal plants -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10329 , http://hdl.handle.net/10948/461 , Rats -- Metabolism , Diabetes -- Research , Medicinal plants -- South Africa
- Description: Type II diabetes is becoming a growing problem in developed countries worldwide. The median age for diagnosis was around sixty, but recent surveys have shown that the entire age distribution curve shifting left. The incidence of type II diabetes is thought to be parallel with the growing rate of obesity associated with an unhealthy western diet. Type II diabetes is an expensive disease to manage, it is for this reason that cheaper medication needs to be investigated in the form of traditional plants, such as Sutherlandia frutescens. Prescription medication, such as tricyclic antidepressants, may also increase body weight thereby playing a role in obesity. The cause of weight gain in such cases may go unrecognized or lead to cessation of the medication with or without the practitioner’s knowledge or approval. It is therefore necessary to investigate the causative agents responsible for the excessive weight gain. Drinking water containing extracts of S. frutescens or metformin was administered to two groups of eleven insulin resistant male Wistar rats. The insulin resistant control group received water without any medication. Rats were sacrificed after 8 weeks allowing for fasting blood glucose, insulin and tissue glycogen content determination. Glucose uptake was also determined using [3H] deoxyglucose. The effect of the medication and the diet on muscle post receptor insulin signaling proteins was determined through Western blots. Liver proteomics was also performed using 2-D electrophoresis. In a separate experiment 26 male Wistar rats were exposed to strepotozotocin toxin, 7 of these rats received intravenous insulin treatment, 7 rats received S. frutescens extract and 7 rats received a combination of both medications, the remaining 5 received no treatment and served as the control. Rats were sacrificed after 6 days allowing for fasting blood glucose, insulin and tissue glycogen content determination. Two groups of 14 male Wistar rats received amitriptyline or trimipramine (common tricyclic antidepressants) in their drinking water, the control group (30 rats) received water without any medication. The rats’ weight and food consumption was monitored throughout the trial and their oxygen consumption was also determined. Rats were sacrificed after 6 weeks or 14 weeks of medicinal compliance allowing for fasting blood glucose, insulin and tissue glycogen content determination. Glucose uptake was also determined using [3H] deoxyglucose. S. frutescens treatment normalized circulating serum insulin levels and significantly increased the rate of glucose clearance. Certain post receptor insulin signaling proteins were also significantly increased relative to the insulin resistant control group. 2-D electrophoresis identified the normalization of protein levels associated with the urea cycle. S. frutescens was also able to, independently; maintain normoglycaemic levels in the strepotozotocin treated group. The tricyclic antidepressants significantly increased blood glucose levels while significantly reducing tissue glycogen levels for both sacrifice periods. Serum insulin remained unchanged while a significant increase in insulin degradation and insulin degrading enzyme levels were found for both antidepressants. S. frutescens shows promise as a low cost antidiabetic medication for future use. Although the antidepressants did not promote weight gain, the increase in blood glucose levels may be cause for concern in patients with a pre-disposition toward developing diabetes.
- Full Text:
- Date Issued: 2006
- Authors: Chadwick, Wayne
- Date: 2006
- Subjects: Rats -- Metabolism , Diabetes -- Research , Medicinal plants -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10329 , http://hdl.handle.net/10948/461 , Rats -- Metabolism , Diabetes -- Research , Medicinal plants -- South Africa
- Description: Type II diabetes is becoming a growing problem in developed countries worldwide. The median age for diagnosis was around sixty, but recent surveys have shown that the entire age distribution curve shifting left. The incidence of type II diabetes is thought to be parallel with the growing rate of obesity associated with an unhealthy western diet. Type II diabetes is an expensive disease to manage, it is for this reason that cheaper medication needs to be investigated in the form of traditional plants, such as Sutherlandia frutescens. Prescription medication, such as tricyclic antidepressants, may also increase body weight thereby playing a role in obesity. The cause of weight gain in such cases may go unrecognized or lead to cessation of the medication with or without the practitioner’s knowledge or approval. It is therefore necessary to investigate the causative agents responsible for the excessive weight gain. Drinking water containing extracts of S. frutescens or metformin was administered to two groups of eleven insulin resistant male Wistar rats. The insulin resistant control group received water without any medication. Rats were sacrificed after 8 weeks allowing for fasting blood glucose, insulin and tissue glycogen content determination. Glucose uptake was also determined using [3H] deoxyglucose. The effect of the medication and the diet on muscle post receptor insulin signaling proteins was determined through Western blots. Liver proteomics was also performed using 2-D electrophoresis. In a separate experiment 26 male Wistar rats were exposed to strepotozotocin toxin, 7 of these rats received intravenous insulin treatment, 7 rats received S. frutescens extract and 7 rats received a combination of both medications, the remaining 5 received no treatment and served as the control. Rats were sacrificed after 6 days allowing for fasting blood glucose, insulin and tissue glycogen content determination. Two groups of 14 male Wistar rats received amitriptyline or trimipramine (common tricyclic antidepressants) in their drinking water, the control group (30 rats) received water without any medication. The rats’ weight and food consumption was monitored throughout the trial and their oxygen consumption was also determined. Rats were sacrificed after 6 weeks or 14 weeks of medicinal compliance allowing for fasting blood glucose, insulin and tissue glycogen content determination. Glucose uptake was also determined using [3H] deoxyglucose. S. frutescens treatment normalized circulating serum insulin levels and significantly increased the rate of glucose clearance. Certain post receptor insulin signaling proteins were also significantly increased relative to the insulin resistant control group. 2-D electrophoresis identified the normalization of protein levels associated with the urea cycle. S. frutescens was also able to, independently; maintain normoglycaemic levels in the strepotozotocin treated group. The tricyclic antidepressants significantly increased blood glucose levels while significantly reducing tissue glycogen levels for both sacrifice periods. Serum insulin remained unchanged while a significant increase in insulin degradation and insulin degrading enzyme levels were found for both antidepressants. S. frutescens shows promise as a low cost antidiabetic medication for future use. Although the antidepressants did not promote weight gain, the increase in blood glucose levels may be cause for concern in patients with a pre-disposition toward developing diabetes.
- Full Text:
- Date Issued: 2006
Metathesis catalysts : an integrated computational, mechanistic and synthetic study
- Authors: Sabbagh, Ingrid Theresa
- Date: 2006
- Subjects: Metathesis (Chemistry) Catalysis Metal catalysts Chemical kinetics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4397 , http://hdl.handle.net/10962/d1006208
- Description: An integrated approach to the design of potential rutheniun-based metathesis catalysts is described, in which closely defined synthetic forays provide the focus and rationale for detailed computational and mechanistic studies. The ground-state geometry of a 1st-generation Grubbs catalyst has been explored at the molecular mechanics, semi-empirical and DFT levels, and the resulting structures have been shown to compare favourably with literature data and with the structure of a known crystalline analogue. The DMol³ DFT code has also been shown to represent accurately both the geometry of the corresponding co-ordinatively unsaturated monophosphine derivative, and the ligand dissociation energy associated with its formation. A DFT free-energy profile of the degenerate metathesis of ethylene has been generated, using a truncated model of the 1st-generation Grubbs catalyst, permitting location, for the first time, of the three expected transition states and providing new information regarding the rate-determining step. DFT methods have been used to facilitate the design of a tridentate camphor-derived ligand for use in the construction of a novel Grubbs-type catalyst. The phosphine ligand dissociation energy of the putative catalyst and the ethylene metathesis energy profile of a truncated model have also been studies at the DFT level. The attempted synthesis of the proposed ligand proceeded via a novel 8-bromocamphoric anhydride intermediate and afforded several unexpected and novel products, including a cisfused γ-Iactone, and a bromo camphoric acid derivative. Single crystal X-ray analysis of the latter reveals a chiral, polymeric H-bonded packing arrangement, rendering it suitable for chiral inclusion studies. Computational methods, including the GAUSSIAN-based GIAO NMR prediction technique, were used to support the structural characterisation of the novel camphor derivatives. DFT-Ievel computational analysis of the C-8- and C-9 bromination of camphor has afforded theoretical insights which permit the reconciliation of two earlier empirical explanations regarding the regioselectivity of these transformations; moreover, the theoretical results suggest that a third, previously disregarded factor, plays a significant role. A coset analysis, in conjunction with DFT-Ievel energy profiling, has also been used to resolve conflicting opinions regarding the origin of the major byproduct. Computed electronic parameters (CEP's) have been calculated for the anionic ligands involved in a series of 2nd-generation Grubbs-Hoveyda-type catalysts, and used to explain some apparently anomalous trends in catalyst activity. A linear relationship between ligand CEP's and selected ¹H NMR chemical shifts has also been demonstrated and used to identify a transient ruthenium complex in solution. The ability of the malonate di-anion to bind to ruthenium in a bidentate manner has been explored and demonstrated, under suitable conditions. DFT methods have been used to design and assess the ruthenium-chelating potential of a novel tridentate malonate derivative. A synthetic pathway to this ligand has been designed and several novel heterocyclic intermediates have been isolated and characterised. An NMR-based kinetic study of the Grubbs-catalysed self-metathesis of l-octene has been completed, and the effects of temperature, concentration and solvent variations on the kinetic parameters have been studied. Application of the Guggenheim method and a simplified mechanistic model has permitted the accurate calculation of pseudorate constants for the initiation and, for the first time, the propagation phase of the reaction. Theoretical studies of this reaction at the DFT and molecular mechanics levels have been shown to support previous assumptions regarding the selectivity and temperature-dependence of metallacycle formation.
- Full Text:
- Date Issued: 2006
- Authors: Sabbagh, Ingrid Theresa
- Date: 2006
- Subjects: Metathesis (Chemistry) Catalysis Metal catalysts Chemical kinetics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4397 , http://hdl.handle.net/10962/d1006208
- Description: An integrated approach to the design of potential rutheniun-based metathesis catalysts is described, in which closely defined synthetic forays provide the focus and rationale for detailed computational and mechanistic studies. The ground-state geometry of a 1st-generation Grubbs catalyst has been explored at the molecular mechanics, semi-empirical and DFT levels, and the resulting structures have been shown to compare favourably with literature data and with the structure of a known crystalline analogue. The DMol³ DFT code has also been shown to represent accurately both the geometry of the corresponding co-ordinatively unsaturated monophosphine derivative, and the ligand dissociation energy associated with its formation. A DFT free-energy profile of the degenerate metathesis of ethylene has been generated, using a truncated model of the 1st-generation Grubbs catalyst, permitting location, for the first time, of the three expected transition states and providing new information regarding the rate-determining step. DFT methods have been used to facilitate the design of a tridentate camphor-derived ligand for use in the construction of a novel Grubbs-type catalyst. The phosphine ligand dissociation energy of the putative catalyst and the ethylene metathesis energy profile of a truncated model have also been studies at the DFT level. The attempted synthesis of the proposed ligand proceeded via a novel 8-bromocamphoric anhydride intermediate and afforded several unexpected and novel products, including a cisfused γ-Iactone, and a bromo camphoric acid derivative. Single crystal X-ray analysis of the latter reveals a chiral, polymeric H-bonded packing arrangement, rendering it suitable for chiral inclusion studies. Computational methods, including the GAUSSIAN-based GIAO NMR prediction technique, were used to support the structural characterisation of the novel camphor derivatives. DFT-Ievel computational analysis of the C-8- and C-9 bromination of camphor has afforded theoretical insights which permit the reconciliation of two earlier empirical explanations regarding the regioselectivity of these transformations; moreover, the theoretical results suggest that a third, previously disregarded factor, plays a significant role. A coset analysis, in conjunction with DFT-Ievel energy profiling, has also been used to resolve conflicting opinions regarding the origin of the major byproduct. Computed electronic parameters (CEP's) have been calculated for the anionic ligands involved in a series of 2nd-generation Grubbs-Hoveyda-type catalysts, and used to explain some apparently anomalous trends in catalyst activity. A linear relationship between ligand CEP's and selected ¹H NMR chemical shifts has also been demonstrated and used to identify a transient ruthenium complex in solution. The ability of the malonate di-anion to bind to ruthenium in a bidentate manner has been explored and demonstrated, under suitable conditions. DFT methods have been used to design and assess the ruthenium-chelating potential of a novel tridentate malonate derivative. A synthetic pathway to this ligand has been designed and several novel heterocyclic intermediates have been isolated and characterised. An NMR-based kinetic study of the Grubbs-catalysed self-metathesis of l-octene has been completed, and the effects of temperature, concentration and solvent variations on the kinetic parameters have been studied. Application of the Guggenheim method and a simplified mechanistic model has permitted the accurate calculation of pseudorate constants for the initiation and, for the first time, the propagation phase of the reaction. Theoretical studies of this reaction at the DFT and molecular mechanics levels have been shown to support previous assumptions regarding the selectivity and temperature-dependence of metallacycle formation.
- Full Text:
- Date Issued: 2006
Monitoring and intelligent control for complex curvature friction stir welding
- Hua, Tao
- Authors: Hua, Tao
- Date: 2006
- Subjects: Friction welding , Fuzzy systems
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:9612 , http://hdl.handle.net/10948/420 , Friction welding , Fuzzy systems
- Description: A multi-input multi-output system to implement on-line process monitoring and intelligent control of complex curvature friction stir welding was proposed. An extra rotation axis was added to the existing three translation axes to perform friction stir welding of complex curvature other than straight welding line. A clamping system was designed for locating and holding the workpieces to bear the large force involved in the process between the welding tool and workpieces. Process parameters (feed rate, spindle speed, tilt angle and plunge depth), and process conditions (parent material and curvature), were used as factors for the orthogonal array experiments to collect sensor data of force, torque and tool temperature using multiple sensors and telemetry system. Using statistic analysis of the experimental data, sensitive signal features were selected to train the feed-forward neural networks, which were used for mapping the relationships between process parameters, process conditions and sensor data. A fuzzy controller with initial input/output membership functions and fuzzy rules generated on-line from the trained neural network was applied to perceive process condition changes and make adjustment of process parameters to maintain tool/workpiece contact and energy input. Input/output scaling factors of the fuzzy controller were tuned on-line to improve output response to the amount and trend of control variable deviation from the reference value. Simulation results showed that the presented neuro-fuzzy control scheme has adaptability to process conditions such as parent material and curvature changes, and that the control variables were well regulated. The presented neuro-fuzzy control scheme can be also expected to be applied in other multi-input multi-output machining processes.
- Full Text:
- Date Issued: 2006
- Authors: Hua, Tao
- Date: 2006
- Subjects: Friction welding , Fuzzy systems
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:9612 , http://hdl.handle.net/10948/420 , Friction welding , Fuzzy systems
- Description: A multi-input multi-output system to implement on-line process monitoring and intelligent control of complex curvature friction stir welding was proposed. An extra rotation axis was added to the existing three translation axes to perform friction stir welding of complex curvature other than straight welding line. A clamping system was designed for locating and holding the workpieces to bear the large force involved in the process between the welding tool and workpieces. Process parameters (feed rate, spindle speed, tilt angle and plunge depth), and process conditions (parent material and curvature), were used as factors for the orthogonal array experiments to collect sensor data of force, torque and tool temperature using multiple sensors and telemetry system. Using statistic analysis of the experimental data, sensitive signal features were selected to train the feed-forward neural networks, which were used for mapping the relationships between process parameters, process conditions and sensor data. A fuzzy controller with initial input/output membership functions and fuzzy rules generated on-line from the trained neural network was applied to perceive process condition changes and make adjustment of process parameters to maintain tool/workpiece contact and energy input. Input/output scaling factors of the fuzzy controller were tuned on-line to improve output response to the amount and trend of control variable deviation from the reference value. Simulation results showed that the presented neuro-fuzzy control scheme has adaptability to process conditions such as parent material and curvature changes, and that the control variables were well regulated. The presented neuro-fuzzy control scheme can be also expected to be applied in other multi-input multi-output machining processes.
- Full Text:
- Date Issued: 2006
Pharmaceutical analysis and drug interaction studies : African potato (Hypoxis hemerocallidea)
- Purushothaman Nair, Vipin Devi Prasad
- Authors: Purushothaman Nair, Vipin Devi Prasad
- Date: 2006
- Subjects: Potatoes -- Africa , Potatoes -- Therapeutic use , AIDS (Disease) -- Treatment , HIV infections -- Drug therapy , Medicinal plants
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3865 , http://hdl.handle.net/10962/d1015802
- Description: In order for a medicinal product to produce a consistent and reliable therapeutic response, it is essential that the final composition of the product is invariable and that the active ingredient/s is/are present in appropriate, non-toxic amounts. However, due to the complexity involved in the standardization of natural products, quality control (QC) criteria and procedures for the registration and market approval of such products are conspicuously absent in most countries around the world. African Potato (AP) is of great medical interest and this particular plant has gained tremendous popularity following the endorsement by the South African Minister of Health as a remedy for HIV/ AIDS patients. Very little information has appeared in the literature to describe methods for the quantitative analysis of hypoxoside, an important component in AP. It has also been claimed that sterols and sterolins present in AP are responsible for its medicinal property but is yet to be proven scientifically. To-date, no QC methods have been reported for the simultaneous quantitative analysis of the combination, β- sitosterol (BSS)/ stigmasterol (STG)/ stigmastanol (STN), purported to be present in preparations containing AP. The effect of concomitant administration of AP and other herbal medicines on the safety and efficacy of conventional medicines has not yet been fully determined. Amongst the objectives of this study was to develop and validate quantitative analytical methods that are suitable for the assay and quality control of plant material, extracts and commercial formulations containing AP. Hypoxoside was isolated from AP and characterized for use as a reference standard for the quality control of AP products and a stability-indicating HPLC/ UV assay method for the quantitative determination of hypoxoside was developed. In addition, a quantitative capillary zone electrophoretic (CZE) method was developed to determine hypoxoside, specifically for its advantages over HPLC. A HPLC method was also developed and validated for the quantitative analysis of BSS, STG and STN in commercially available oral dosage forms containing AP material or extracts thereof. The antioxidant activity of an aqueous extract of lyophilized corms of AP along with hypoxoside and rooperol were investigated. In comparison with the AP extracts and also with hypoxoside, rooperol showed significant antioxidant activity. The capacity of AP, (extracts, formulations, hypoxoside and rooperol as well as sterols to inhibit in vitro metabolism of drug substrates by human cytochrome P450 (CYP) enzymes such as CYP 3A4, 3A5 and CYP19 were investigated. Samples were also assessed for their effect on drug transport proteins such as P-glycoprotein (P-gp). Various extracts of AP, AP formulations, stigmasterol and the norlignans, in particular the aglycone rooperol, exhibited inhibitory effects on CYP 3A4, 3A5 and CYP19 mediated metabolism.These results suggest that concurrent therapy with AP and other medicines, in particular antiretroviral drugs, can have important implications for safety and efficacy. Large discrepancies in marker content between AP products were found. Dissolution testing of AP products was investigated as a QC tool and the results also revealed inconsistencies between different AP products.
- Full Text:
- Date Issued: 2006
- Authors: Purushothaman Nair, Vipin Devi Prasad
- Date: 2006
- Subjects: Potatoes -- Africa , Potatoes -- Therapeutic use , AIDS (Disease) -- Treatment , HIV infections -- Drug therapy , Medicinal plants
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3865 , http://hdl.handle.net/10962/d1015802
- Description: In order for a medicinal product to produce a consistent and reliable therapeutic response, it is essential that the final composition of the product is invariable and that the active ingredient/s is/are present in appropriate, non-toxic amounts. However, due to the complexity involved in the standardization of natural products, quality control (QC) criteria and procedures for the registration and market approval of such products are conspicuously absent in most countries around the world. African Potato (AP) is of great medical interest and this particular plant has gained tremendous popularity following the endorsement by the South African Minister of Health as a remedy for HIV/ AIDS patients. Very little information has appeared in the literature to describe methods for the quantitative analysis of hypoxoside, an important component in AP. It has also been claimed that sterols and sterolins present in AP are responsible for its medicinal property but is yet to be proven scientifically. To-date, no QC methods have been reported for the simultaneous quantitative analysis of the combination, β- sitosterol (BSS)/ stigmasterol (STG)/ stigmastanol (STN), purported to be present in preparations containing AP. The effect of concomitant administration of AP and other herbal medicines on the safety and efficacy of conventional medicines has not yet been fully determined. Amongst the objectives of this study was to develop and validate quantitative analytical methods that are suitable for the assay and quality control of plant material, extracts and commercial formulations containing AP. Hypoxoside was isolated from AP and characterized for use as a reference standard for the quality control of AP products and a stability-indicating HPLC/ UV assay method for the quantitative determination of hypoxoside was developed. In addition, a quantitative capillary zone electrophoretic (CZE) method was developed to determine hypoxoside, specifically for its advantages over HPLC. A HPLC method was also developed and validated for the quantitative analysis of BSS, STG and STN in commercially available oral dosage forms containing AP material or extracts thereof. The antioxidant activity of an aqueous extract of lyophilized corms of AP along with hypoxoside and rooperol were investigated. In comparison with the AP extracts and also with hypoxoside, rooperol showed significant antioxidant activity. The capacity of AP, (extracts, formulations, hypoxoside and rooperol as well as sterols to inhibit in vitro metabolism of drug substrates by human cytochrome P450 (CYP) enzymes such as CYP 3A4, 3A5 and CYP19 were investigated. Samples were also assessed for their effect on drug transport proteins such as P-glycoprotein (P-gp). Various extracts of AP, AP formulations, stigmasterol and the norlignans, in particular the aglycone rooperol, exhibited inhibitory effects on CYP 3A4, 3A5 and CYP19 mediated metabolism.These results suggest that concurrent therapy with AP and other medicines, in particular antiretroviral drugs, can have important implications for safety and efficacy. Large discrepancies in marker content between AP products were found. Dissolution testing of AP products was investigated as a QC tool and the results also revealed inconsistencies between different AP products.
- Full Text:
- Date Issued: 2006
Plastochron index - an indicator of plant structure and function a case study using Pisum sativum L
- Ade-Ademilua, Omobolanle Elizabeth
- Authors: Ade-Ademilua, Omobolanle Elizabeth
- Date: 2006
- Subjects: Plant anatomy Plant physiology Peas -- Anatomy Peas -- Physiology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4183 , http://hdl.handle.net/10962/d1003751
- Description: The use of chronological age for example, using days after sowing (DAS), or days after germination (DAG) as a time variable may result in the inherent variability between plants resulting in differences which can be large enough to obscure subtle developmental trends that become evident among plants sown at the same time. An alternative to DAS or DAG is the plastochron index (PI), first used by Erickson and Michelini (1957) as a morphological time scale and numerical index; which to according to the authors suggested and represented a more accurate reflection of the developmental status of a plant. The research presented in this thesis was therefore aimed specifically at utilizing the index in qualitative and quantitative analyses, to confirm its usefulness in analyzing and predicting plant growth and development. Specifically this research focused on investigating various morphological and physiological events that together, hopefully, would serve as a template for the prediction of the growth, development and reactions of Pisum sativum L. to different growth conditions. In Chapter 3, the use of the average length of the first pair of leaflets on each node as a suitable parameter for calculating PI in P. sativum is suggested. The results presented in Chapter 3 suggest that plant age is best expressed using the plastochron index, as this reflects the time interval between the initiations of successive pairs of leaflets. This section of the research has been published as “Ade-Ademilua OE, Botha CEJ (2005) A re-evaluation of plastochron index in peas - a case for using leaflet length. South African Journal of Botany 71: 76-80”. The PI formula developed was subsequently used in this research to conduct qualitative and quantitative investigations of plant growth and development in which all data and observations were related directly to the plastochron index. In Chapter 4, the sink to source transition in Pisum sativum L. leaves at different plastochron ages in nodulating plants was investigated using the phloem-mobile fluorescent marker, 5,6-carboxyfluorescein (5,6-CF). The results demonstrated that young leaves remained strong sinks up until LPI 0, after which sink-source transition occurred up to LPI 1.8 and leaflets transitioned to strong source systems by LPI 2.0. A well-developed cross-connected phloem system between paired leaflets in peas, and the petiole and the stem vascular supply was observed. The data presented in the second part of Chapter 4 suggest that the phloem transport between leaflet pairs is independent of the sink/source state of the leaflets, or of movement along the source to sink gradient. The data support the presence of a modular transport system which may ensure re-allocation and balancing between leaflets of the same physiological age and photosynthetic and transport status, thereby load-balancing the local transport system, before exporting to other younger (sink) regions. The investigation of leaf development using the plastochron index (Chapter 5) revealed that the formation of air spaces in the palisade and spongy mesophyll, one of the preparatory events for transition from sink to source state in developing leaves, occurs between LPI 0 and LPI 1 in pea leaflets. Results of the anatomical and ultrastructural study related to PI are presented in Chapter 5. The density of wall ingrowths in transfer cells of minor veins increased with LPI and appeared to be associated with the probable transition to source state and the related potential increase in the production of assimilates for export. The onset of wall ingrowth development in leaflets at LPI 0 provided evidence that sink-to-source transition commences at LPI 0 in P. sativum. Presumably-functional plasmodesmata as well as a few mature sieve elements were evident in class IV veins in the apical region of young and older leaflets at LPI 0. The number of mature sieve elements per vein however, increased with increasing LPI. Most class V veins were still undergoing division at LPI 0 and their sieve elements did not show signs of maturity until LPI 1. The increase in the number of mature metaphloem sieve elements in young, supposedly importing tissue at LPI 0 to older, supposedly exporting tissues at LPI 2 is evidence of the association between phloem maturation and transition from importing to exporting status. In Chapter 6, I report on the effects of elevated CO[subscript 2] on the growth and leaf development of nodulating and non-nodulating Pisum sativum L var. Greenfeast grown under controlled environment of the same nitrogen (6mM) and nitrogen- free nutrient solution conditions. Shortterm exposure to elevated CO[subscript 2] induced rapid plant growth, irrespective of treatment. However, long-term elevated CO[subscript 2] treatment did not affect rate of leaf appearance (RLA) in nodulated plants, irrespective of mineral N supply but enhanced RLA in non- nodulating plants supplied with mineral N. Supplied N resulted in a significant increase in leaflet elongation rate (LfER) under both ambient and elevated CO[subscript 2], but LfER was not significantly affected by nodulation but was increased by high CO[subscript 2]. This suggested that the growth of nodulating P. sativum L may not be significantly affected under CO[subscript 2] levels as high as 1000 μmol mol[superscript -1]. The data suggest that elevated CO[subscript 2] will enhance canopy size, provided adequate soil N is available and more so in non-nodulating plants. This section of the research has been published as “Ade-Ademilua OE, Botha CEJ (2004) The effects of elevated CO[subscript 2] and nitrogen availability supersedes the need for nodulation in peas grown under controlled environmental conditions. South African Journal of Botany 70: 816 – 823”. This thesis demonstrates that the similarity in the qualitative analyses results obtained from plants from different CO[subscript 2], nitrogen and nodulation treatment conditions, highlights the fact that plants of same PI value are at the same developmental state, irrespective of the growth condition. Furthermore, changes in plant structure and function observed under different growth conditions can be related simply to changes in plastochron index. The work presented in this thesis demonstrate that changes in plant structure and function analyzed are related to changes in PI. An important finding of this thesis is that with the use of PI, results can be compiled as a template for predicting the structure- function state of pea plants at any plastochron age, under any growth conditions, before using small representative sample populations.
- Full Text:
- Date Issued: 2006
- Authors: Ade-Ademilua, Omobolanle Elizabeth
- Date: 2006
- Subjects: Plant anatomy Plant physiology Peas -- Anatomy Peas -- Physiology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4183 , http://hdl.handle.net/10962/d1003751
- Description: The use of chronological age for example, using days after sowing (DAS), or days after germination (DAG) as a time variable may result in the inherent variability between plants resulting in differences which can be large enough to obscure subtle developmental trends that become evident among plants sown at the same time. An alternative to DAS or DAG is the plastochron index (PI), first used by Erickson and Michelini (1957) as a morphological time scale and numerical index; which to according to the authors suggested and represented a more accurate reflection of the developmental status of a plant. The research presented in this thesis was therefore aimed specifically at utilizing the index in qualitative and quantitative analyses, to confirm its usefulness in analyzing and predicting plant growth and development. Specifically this research focused on investigating various morphological and physiological events that together, hopefully, would serve as a template for the prediction of the growth, development and reactions of Pisum sativum L. to different growth conditions. In Chapter 3, the use of the average length of the first pair of leaflets on each node as a suitable parameter for calculating PI in P. sativum is suggested. The results presented in Chapter 3 suggest that plant age is best expressed using the plastochron index, as this reflects the time interval between the initiations of successive pairs of leaflets. This section of the research has been published as “Ade-Ademilua OE, Botha CEJ (2005) A re-evaluation of plastochron index in peas - a case for using leaflet length. South African Journal of Botany 71: 76-80”. The PI formula developed was subsequently used in this research to conduct qualitative and quantitative investigations of plant growth and development in which all data and observations were related directly to the plastochron index. In Chapter 4, the sink to source transition in Pisum sativum L. leaves at different plastochron ages in nodulating plants was investigated using the phloem-mobile fluorescent marker, 5,6-carboxyfluorescein (5,6-CF). The results demonstrated that young leaves remained strong sinks up until LPI 0, after which sink-source transition occurred up to LPI 1.8 and leaflets transitioned to strong source systems by LPI 2.0. A well-developed cross-connected phloem system between paired leaflets in peas, and the petiole and the stem vascular supply was observed. The data presented in the second part of Chapter 4 suggest that the phloem transport between leaflet pairs is independent of the sink/source state of the leaflets, or of movement along the source to sink gradient. The data support the presence of a modular transport system which may ensure re-allocation and balancing between leaflets of the same physiological age and photosynthetic and transport status, thereby load-balancing the local transport system, before exporting to other younger (sink) regions. The investigation of leaf development using the plastochron index (Chapter 5) revealed that the formation of air spaces in the palisade and spongy mesophyll, one of the preparatory events for transition from sink to source state in developing leaves, occurs between LPI 0 and LPI 1 in pea leaflets. Results of the anatomical and ultrastructural study related to PI are presented in Chapter 5. The density of wall ingrowths in transfer cells of minor veins increased with LPI and appeared to be associated with the probable transition to source state and the related potential increase in the production of assimilates for export. The onset of wall ingrowth development in leaflets at LPI 0 provided evidence that sink-to-source transition commences at LPI 0 in P. sativum. Presumably-functional plasmodesmata as well as a few mature sieve elements were evident in class IV veins in the apical region of young and older leaflets at LPI 0. The number of mature sieve elements per vein however, increased with increasing LPI. Most class V veins were still undergoing division at LPI 0 and their sieve elements did not show signs of maturity until LPI 1. The increase in the number of mature metaphloem sieve elements in young, supposedly importing tissue at LPI 0 to older, supposedly exporting tissues at LPI 2 is evidence of the association between phloem maturation and transition from importing to exporting status. In Chapter 6, I report on the effects of elevated CO[subscript 2] on the growth and leaf development of nodulating and non-nodulating Pisum sativum L var. Greenfeast grown under controlled environment of the same nitrogen (6mM) and nitrogen- free nutrient solution conditions. Shortterm exposure to elevated CO[subscript 2] induced rapid plant growth, irrespective of treatment. However, long-term elevated CO[subscript 2] treatment did not affect rate of leaf appearance (RLA) in nodulated plants, irrespective of mineral N supply but enhanced RLA in non- nodulating plants supplied with mineral N. Supplied N resulted in a significant increase in leaflet elongation rate (LfER) under both ambient and elevated CO[subscript 2], but LfER was not significantly affected by nodulation but was increased by high CO[subscript 2]. This suggested that the growth of nodulating P. sativum L may not be significantly affected under CO[subscript 2] levels as high as 1000 μmol mol[superscript -1]. The data suggest that elevated CO[subscript 2] will enhance canopy size, provided adequate soil N is available and more so in non-nodulating plants. This section of the research has been published as “Ade-Ademilua OE, Botha CEJ (2004) The effects of elevated CO[subscript 2] and nitrogen availability supersedes the need for nodulation in peas grown under controlled environmental conditions. South African Journal of Botany 70: 816 – 823”. This thesis demonstrates that the similarity in the qualitative analyses results obtained from plants from different CO[subscript 2], nitrogen and nodulation treatment conditions, highlights the fact that plants of same PI value are at the same developmental state, irrespective of the growth condition. Furthermore, changes in plant structure and function observed under different growth conditions can be related simply to changes in plastochron index. The work presented in this thesis demonstrate that changes in plant structure and function analyzed are related to changes in PI. An important finding of this thesis is that with the use of PI, results can be compiled as a template for predicting the structure- function state of pea plants at any plastochron age, under any growth conditions, before using small representative sample populations.
- Full Text:
- Date Issued: 2006
Population dynamics of the raggedtooth shark (carcharias taurus) along the east coast of South Africa
- Authors: Dicken, Matthew Laurence
- Date: 2006
- Subjects: Sharks -- South Africa Shark fisheries -- South Africa Fish populations -- South Africa Sand tiger shark Fish tagging -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5310 , http://hdl.handle.net/10962/d1005155
- Description: This thesis develops the first open population model for any shark species worldwide using the Cormack-Jolly-Seber (CJS) model. In conjunction with a tagging study, five auxiliary studies were conducted to investigate stock structure, post-release mortality, tag shedding, and tag-reporting rates. The results from each of the studies were used to correct for any violations of the models assumptions to provide the first unbiased estimates of survival and abundance for the raggedtooth shark (Carcharias taurus) in South Africa. The C. taurus population exhibited complex stock structuring, by size and sex. Competitive shore anglers fished an estimated 37, 820 fishing days.year⁻¹ (95% C.I. = 28, 281 - 47, 359 days.year⁻¹) for sharks, and caught 1764 (95% C.I. = 321 – 3207) C. taurus. Although released alive, post-release mortality ranged from 3.85% for young-of-the-year sharks to 18.46% for adult sharks. Between 1984 and 2004, a total of 3471 C. taurus were tagged. In all, 302-tagged sharks (8.7%) were recaptured. Both juvenile (< 1.8 m TL) and adult sharks (> 1.8 m TL) displayed philopatric behaviour for specific parts of their ranges, including gestating and parturition areas. Significant differences were observed in the percentage of recaptures between the different tag types, tagging programs, individual taggers and capture methods used to tag sharks. The annual tag retention rate for juvenile sharks, 94.19% (95% C.I. = 80.68% - 100.00%) was significantly higher than for adult sharks, estimated at 29.00% (95% C.I. = 6.76% - 64.39%). Tag reporting rates, from fishermen varied both spatially and temporally from 0.28 (95% C.I. = 0.00 – 0.63) to 0.77 (95% C.I. = 0.56 – 0.97). Associated tag wound damage and biofouling growth indicated that B-type tags were a suitable tag type for use on C. taurus, whereas C-type tags were not. The CJS bias-adjusted estimate for juvenile survival was 0.456 (95% C.I. = 0.367 – 0.516) and for adult sharks, 0.865 (95% C.I. = 0.795 – 0.915). From 1984 to 2004 the mean bias-adjusted population size for juvenile sharks was estimated at 3506 (95% C.I. = 2433 – 4350) and for adult sharks, 5899 (95% C.I. = 7216 – 11904). Trends in abundance over the 20-year study period indicated a stable, healthy population.
- Full Text:
- Date Issued: 2006
- Authors: Dicken, Matthew Laurence
- Date: 2006
- Subjects: Sharks -- South Africa Shark fisheries -- South Africa Fish populations -- South Africa Sand tiger shark Fish tagging -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5310 , http://hdl.handle.net/10962/d1005155
- Description: This thesis develops the first open population model for any shark species worldwide using the Cormack-Jolly-Seber (CJS) model. In conjunction with a tagging study, five auxiliary studies were conducted to investigate stock structure, post-release mortality, tag shedding, and tag-reporting rates. The results from each of the studies were used to correct for any violations of the models assumptions to provide the first unbiased estimates of survival and abundance for the raggedtooth shark (Carcharias taurus) in South Africa. The C. taurus population exhibited complex stock structuring, by size and sex. Competitive shore anglers fished an estimated 37, 820 fishing days.year⁻¹ (95% C.I. = 28, 281 - 47, 359 days.year⁻¹) for sharks, and caught 1764 (95% C.I. = 321 – 3207) C. taurus. Although released alive, post-release mortality ranged from 3.85% for young-of-the-year sharks to 18.46% for adult sharks. Between 1984 and 2004, a total of 3471 C. taurus were tagged. In all, 302-tagged sharks (8.7%) were recaptured. Both juvenile (< 1.8 m TL) and adult sharks (> 1.8 m TL) displayed philopatric behaviour for specific parts of their ranges, including gestating and parturition areas. Significant differences were observed in the percentage of recaptures between the different tag types, tagging programs, individual taggers and capture methods used to tag sharks. The annual tag retention rate for juvenile sharks, 94.19% (95% C.I. = 80.68% - 100.00%) was significantly higher than for adult sharks, estimated at 29.00% (95% C.I. = 6.76% - 64.39%). Tag reporting rates, from fishermen varied both spatially and temporally from 0.28 (95% C.I. = 0.00 – 0.63) to 0.77 (95% C.I. = 0.56 – 0.97). Associated tag wound damage and biofouling growth indicated that B-type tags were a suitable tag type for use on C. taurus, whereas C-type tags were not. The CJS bias-adjusted estimate for juvenile survival was 0.456 (95% C.I. = 0.367 – 0.516) and for adult sharks, 0.865 (95% C.I. = 0.795 – 0.915). From 1984 to 2004 the mean bias-adjusted population size for juvenile sharks was estimated at 3506 (95% C.I. = 2433 – 4350) and for adult sharks, 5899 (95% C.I. = 7216 – 11904). Trends in abundance over the 20-year study period indicated a stable, healthy population.
- Full Text:
- Date Issued: 2006
Reactions in the solid state
- Authors: Brown, Michael Ewart
- Date: 2006
- Subjects: Solid state chemistry , Thermal analysis , Chemistry, Analytic
- Language: English
- Type: Thesis , Doctoral , DSc
- Identifier: vital:4529 , http://hdl.handle.net/10962/d1015762
- Description: I have chosen the title for this thesis, "Reactions in the Solid State", for two reasons: Firstly, it is broad enough to cover all of my areas of research, which have been: • Effects of irradiation on solids (PhD topic) • Silver refining (while at the Chamber of Mines) • Kinetics of decomposition of solids (with Dr A.K. Galwey and various others) • Techniques of thermal analysis • Pyrotechnic delay systems (with support from AECI Explosives) • Thermal and photostability of drugs (with Prof B.D. Glass) and, secondly, it was the title of the very successful book co-authored by Drs Andrew Galwey, David Dollimore and me. A large part of my research has been involved in the writing and editing of books, so these are covered in a separate commentary, while commentary on the more than 100 papers to which I have contributed forms the main part of this compilation. It is hoped that the electronic format will enable ready access of to all aspects of my research, including electronic versions of the original papers. The reader will need a copy of Adobe Acrobat Reader to access these.
- Full Text:
- Date Issued: 2006
- Authors: Brown, Michael Ewart
- Date: 2006
- Subjects: Solid state chemistry , Thermal analysis , Chemistry, Analytic
- Language: English
- Type: Thesis , Doctoral , DSc
- Identifier: vital:4529 , http://hdl.handle.net/10962/d1015762
- Description: I have chosen the title for this thesis, "Reactions in the Solid State", for two reasons: Firstly, it is broad enough to cover all of my areas of research, which have been: • Effects of irradiation on solids (PhD topic) • Silver refining (while at the Chamber of Mines) • Kinetics of decomposition of solids (with Dr A.K. Galwey and various others) • Techniques of thermal analysis • Pyrotechnic delay systems (with support from AECI Explosives) • Thermal and photostability of drugs (with Prof B.D. Glass) and, secondly, it was the title of the very successful book co-authored by Drs Andrew Galwey, David Dollimore and me. A large part of my research has been involved in the writing and editing of books, so these are covered in a separate commentary, while commentary on the more than 100 papers to which I have contributed forms the main part of this compilation. It is hoped that the electronic format will enable ready access of to all aspects of my research, including electronic versions of the original papers. The reader will need a copy of Adobe Acrobat Reader to access these.
- Full Text:
- Date Issued: 2006
Redress for victims of crime in South Africa: a comparison with selected Commonwealth jurisdictions
- Von Bonde, Johannes Christian
- Authors: Von Bonde, Johannes Christian
- Date: 2006
- Subjects: Victims of crimes -- Legal status, laws, etc. -- South Africa , Reparation (Criminal justice) -- South Africa
- Language: English
- Type: Thesis , Doctoral , LLD
- Identifier: vital:10268 , http://hdl.handle.net/10948/640 , Victims of crimes -- Legal status, laws, etc. -- South Africa , Reparation (Criminal justice) -- South Africa
- Description: In terms of the Constitution every person has the right to freedom and security of the person. This includes the right to be free from all forms of violence from either public or private sources. The state is charged with the duty to protect the individual from such harm. While the Constitution refers to the protection of victims of crime in broad and general terms without indicating how these rights should be protected, it makes meticulous and detailed provision for the rights of arrested, detained and accused persons. This leads to the popular belief that the Constitution protects the criminal and not the victim, engendering public dissatisfaction with the status quo, which is amplified by the fact that South Africa’s current legal dispensation for victims of crime does not embody the requirements of ubuntu and African customary law, which the Constitution declares to be binding on South African courts. This study analyses the means that exist in South African law for the victim of crime to obtain redress for criminal acts and proposes effective avenues through which victims can obtain redress, should the existing machinery prove to be inadequate. The term restitution is used to indicate recompense obtained from the perpetrator, while the term compensation refers to recompense obtained from the state. A comparative study is conducted to ascertain how the legal position of victims of crime in South Africa compares with that of victims of crime in Great Britain, India and New Zealand, respectively. South Africa does not have a state-funded victim compensation scheme such as those which exist in most developed countries. The respective proposals of the South African Law Commission for a victim compensation scheme and revised legislation to deal with offender/victim restitution are considered critically, inter alia, in the light of the findings of the comparative study. Proposals are made regarding changes to the South African legal system to bring it in line with international developments regarding restitution and compensation to victims of crime, attention being given to the meaning, significance and implementation of the doctrine of restorative justice when dealing with the aftermath of criminal injury. In addition to a complete revision of South African legislation dealing with offender/victim restitution, this study recommends the consolidation of the Road Accident Fund and the Compensation Fund operating in terms of the Compensation for Occupational Injuries and Diseases Act. These two bodies should be amalgamated to create a unified Compensation Scheme to compensate victims of crime, as well as victims of traffic and industrial injuries. General qualifying criteria for claimants would be drafted, with specific criteria applying in cases of traffic, industrial and crime related injuries, respectively.
- Full Text:
- Date Issued: 2006
- Authors: Von Bonde, Johannes Christian
- Date: 2006
- Subjects: Victims of crimes -- Legal status, laws, etc. -- South Africa , Reparation (Criminal justice) -- South Africa
- Language: English
- Type: Thesis , Doctoral , LLD
- Identifier: vital:10268 , http://hdl.handle.net/10948/640 , Victims of crimes -- Legal status, laws, etc. -- South Africa , Reparation (Criminal justice) -- South Africa
- Description: In terms of the Constitution every person has the right to freedom and security of the person. This includes the right to be free from all forms of violence from either public or private sources. The state is charged with the duty to protect the individual from such harm. While the Constitution refers to the protection of victims of crime in broad and general terms without indicating how these rights should be protected, it makes meticulous and detailed provision for the rights of arrested, detained and accused persons. This leads to the popular belief that the Constitution protects the criminal and not the victim, engendering public dissatisfaction with the status quo, which is amplified by the fact that South Africa’s current legal dispensation for victims of crime does not embody the requirements of ubuntu and African customary law, which the Constitution declares to be binding on South African courts. This study analyses the means that exist in South African law for the victim of crime to obtain redress for criminal acts and proposes effective avenues through which victims can obtain redress, should the existing machinery prove to be inadequate. The term restitution is used to indicate recompense obtained from the perpetrator, while the term compensation refers to recompense obtained from the state. A comparative study is conducted to ascertain how the legal position of victims of crime in South Africa compares with that of victims of crime in Great Britain, India and New Zealand, respectively. South Africa does not have a state-funded victim compensation scheme such as those which exist in most developed countries. The respective proposals of the South African Law Commission for a victim compensation scheme and revised legislation to deal with offender/victim restitution are considered critically, inter alia, in the light of the findings of the comparative study. Proposals are made regarding changes to the South African legal system to bring it in line with international developments regarding restitution and compensation to victims of crime, attention being given to the meaning, significance and implementation of the doctrine of restorative justice when dealing with the aftermath of criminal injury. In addition to a complete revision of South African legislation dealing with offender/victim restitution, this study recommends the consolidation of the Road Accident Fund and the Compensation Fund operating in terms of the Compensation for Occupational Injuries and Diseases Act. These two bodies should be amalgamated to create a unified Compensation Scheme to compensate victims of crime, as well as victims of traffic and industrial injuries. General qualifying criteria for claimants would be drafted, with specific criteria applying in cases of traffic, industrial and crime related injuries, respectively.
- Full Text:
- Date Issued: 2006
Restoring trust by verifying information integrity through continuous auditing
- Authors: Flowerday, Stephen
- Date: 2006
- Subjects: Auditing, Internal , Corporate governance
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:9796 , http://hdl.handle.net/10948/504 , http://hdl.handle.net/10948/d1011920 , Auditing, Internal , Corporate governance
- Description: Corporate scandals such as Enron, WorldCom and Parmalat, have focused recent governance efforts in the domain of financial reporting due to fraudulent and/or erroneous accounting practices. In addition, the ineffectiveness of the current system of controls has been highlighted, including that some directors have been weak and ineffective monitors of managers. This board of director ‘weakness’ has called for additional mechanisms for monitoring and controlling of management, focusing on financial reporting. This problem intensifies in that today companies function in real-time, and decisions are based on available realtime financial information. However, the assurances provided by traditional auditing take place months after the transactions have occurred and therefore, a trust problem arises because information is not verified in real-time. Consequently, the errors and fraud concealed within the financial information is not discovered until months later. To address this trust problem a conceptual causal model is proposed in this study based on the principles of systems theory. The emergent property of the causal model is increased trust and control. This study establishes that mutual assurances assist in building trust and that information security assists in safeguarding trust. Subsequently, in order to have a positive relationship between the company directors and various stakeholders, uncertainty needs to be contained, and the level of trust needs to surpass the perceived risks. The study concludes that assurances need to be provided in real-time to restore stakeholder confidence and trust in the domain of financial reporting. In order to provide assurances in real-time, continuous auditing is required to verify the integrity of financial information when it becomes available, and not months later. A continuous auditing process has its foundations grounded in information technology and attends to the challenges in real-time by addressing the standardisation of data to enable effective analysis, the validation of the accuracy of the data and the reliability of the system.
- Full Text:
- Date Issued: 2006
- Authors: Flowerday, Stephen
- Date: 2006
- Subjects: Auditing, Internal , Corporate governance
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:9796 , http://hdl.handle.net/10948/504 , http://hdl.handle.net/10948/d1011920 , Auditing, Internal , Corporate governance
- Description: Corporate scandals such as Enron, WorldCom and Parmalat, have focused recent governance efforts in the domain of financial reporting due to fraudulent and/or erroneous accounting practices. In addition, the ineffectiveness of the current system of controls has been highlighted, including that some directors have been weak and ineffective monitors of managers. This board of director ‘weakness’ has called for additional mechanisms for monitoring and controlling of management, focusing on financial reporting. This problem intensifies in that today companies function in real-time, and decisions are based on available realtime financial information. However, the assurances provided by traditional auditing take place months after the transactions have occurred and therefore, a trust problem arises because information is not verified in real-time. Consequently, the errors and fraud concealed within the financial information is not discovered until months later. To address this trust problem a conceptual causal model is proposed in this study based on the principles of systems theory. The emergent property of the causal model is increased trust and control. This study establishes that mutual assurances assist in building trust and that information security assists in safeguarding trust. Subsequently, in order to have a positive relationship between the company directors and various stakeholders, uncertainty needs to be contained, and the level of trust needs to surpass the perceived risks. The study concludes that assurances need to be provided in real-time to restore stakeholder confidence and trust in the domain of financial reporting. In order to provide assurances in real-time, continuous auditing is required to verify the integrity of financial information when it becomes available, and not months later. A continuous auditing process has its foundations grounded in information technology and attends to the challenges in real-time by addressing the standardisation of data to enable effective analysis, the validation of the accuracy of the data and the reliability of the system.
- Full Text:
- Date Issued: 2006
South Africa's chemical and biological warfare programme 1981-1995
- Authors: Gould, Chandré
- Date: 2006
- Subjects: Basson, Wouter, 1950- Basson, Wouter, 1950 -- Trials, litigation, etc Biological warfare -- South Africa Chemical warfare -- South Africa Trials (Political crimes and offenses) -- South Africa South Africa -- Politics and government -- History
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2544 , http://hdl.handle.net/10962/d1002396
- Description: In 1981 the apartheid military initiated a chemical and biological warfare (CBW) programme (code-named Project Coast). The programme, terminated in 1993, was aimed at developing novel irritating and incapacitating agents for internal and external use, covert assassination weapons for use against apartheid opponents, and defensive equipment for use by South African Defence Force (SADF) troops in Angola. The CBW programme was driven by a single individual, Dr Wouter Basson, who reported to a military management committee (the Co-ordinating Management Committee) which comprised a select group of high ranking officers. Practical and financial oversight of the programme was weak which allowed both for the abuse of programme funds and for senior military officers to deny knowledge of aspects of the programme. The biological component of Project Coast was conducted in violation of the commitments of the South African government to the Biological and Toxins Weapons Convention (BTWC). While the state’s commitment to the BTWC was one of the factors considered when initiating the programme, it was not a sufficient constraint to prevent the development of the biological weapons programme, but rather influenced its structure such that the programme could avoid national and international detection. Despite efforts to conceal the military front companies where the chemical and biological warfare (CBW) research and development was undertaken, evidence presented in this thesis shows that the United States had sufficient information about the programme to have been aware of its existence. Yet, it was only in 1993, on the eve of the democratic election in South Africa, that any attempt was made by the US administration to pressure the government to terminate the programme. This thesis considers the factors which influenced the decision to develop Project Coast; the structure and nature of the programme; the motivations of scientists to become involved in the programme and remain involved; the use of chemical and biological agents against opponents of the state, and the factors which influenced the termination of the programme on the eve of the first democratic elections in 1994. It also considers the nature and exent of international support, both tacit and overt, for the programme and argues that the failure of Western nations to call for the termination of the programme before the early 1990s was a function of political expediency and indicates a significant weakness in the ability of international agreements to constrain the development of such programmes.
- Full Text:
- Date Issued: 2006
- Authors: Gould, Chandré
- Date: 2006
- Subjects: Basson, Wouter, 1950- Basson, Wouter, 1950 -- Trials, litigation, etc Biological warfare -- South Africa Chemical warfare -- South Africa Trials (Political crimes and offenses) -- South Africa South Africa -- Politics and government -- History
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2544 , http://hdl.handle.net/10962/d1002396
- Description: In 1981 the apartheid military initiated a chemical and biological warfare (CBW) programme (code-named Project Coast). The programme, terminated in 1993, was aimed at developing novel irritating and incapacitating agents for internal and external use, covert assassination weapons for use against apartheid opponents, and defensive equipment for use by South African Defence Force (SADF) troops in Angola. The CBW programme was driven by a single individual, Dr Wouter Basson, who reported to a military management committee (the Co-ordinating Management Committee) which comprised a select group of high ranking officers. Practical and financial oversight of the programme was weak which allowed both for the abuse of programme funds and for senior military officers to deny knowledge of aspects of the programme. The biological component of Project Coast was conducted in violation of the commitments of the South African government to the Biological and Toxins Weapons Convention (BTWC). While the state’s commitment to the BTWC was one of the factors considered when initiating the programme, it was not a sufficient constraint to prevent the development of the biological weapons programme, but rather influenced its structure such that the programme could avoid national and international detection. Despite efforts to conceal the military front companies where the chemical and biological warfare (CBW) research and development was undertaken, evidence presented in this thesis shows that the United States had sufficient information about the programme to have been aware of its existence. Yet, it was only in 1993, on the eve of the democratic election in South Africa, that any attempt was made by the US administration to pressure the government to terminate the programme. This thesis considers the factors which influenced the decision to develop Project Coast; the structure and nature of the programme; the motivations of scientists to become involved in the programme and remain involved; the use of chemical and biological agents against opponents of the state, and the factors which influenced the termination of the programme on the eve of the first democratic elections in 1994. It also considers the nature and exent of international support, both tacit and overt, for the programme and argues that the failure of Western nations to call for the termination of the programme before the early 1990s was a function of political expediency and indicates a significant weakness in the ability of international agreements to constrain the development of such programmes.
- Full Text:
- Date Issued: 2006
Studies of equivalent fuzzy subgroups of finite abelian p-Groups of rank two and their subgroup lattices
- Authors: Ngcibi, Sakhile Leonard
- Date: 2006
- Subjects: Abelian groups Fuzzy sets Finite groups Group theory Polynomials
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5416 , http://hdl.handle.net/10962/d1005230
- Description: We determine the number and nature of distinct equivalence classes of fuzzy subgroups of finite Abelian p-group G of rank two under a natural equivalence relation on fuzzy subgroups. Our discussions embrace the necessary theory from groups with special emphasis on finite p-groups as a step towards the classification of crisp subgroups as well as maximal chains of subgroups. Unique naming of subgroup generators as discussed in this work facilitates counting of subgroups and chains of subgroups from subgroup lattices of the groups. We cover aspects of fuzzy theory including fuzzy (homo-) isomorphism together with operations on fuzzy subgroups. The equivalence characterization as discussed here is finer than isomorphism. We introduce the theory of keychains with a view towards the enumeration of maximal chains as well as fuzzy subgroups under the equivalence relation mentioned above. We discuss a strategy to develop subgroup lattices of the groups used in the discussion, and give examples for specific cases of prime p and positive integers n,m. We derive formulas for both the number of maximal chains as well as the number of distinct equivalence classes of fuzzy subgroups. The results are in the form of polynomials in p (known in the literature as Hall polynomials) with combinatorial coefficients. Finally we give a brief investigation of the results from a graph-theoretic point of view. We view the subgroup lattices of these groups as simple, connected, symmetric graphs.
- Full Text:
- Date Issued: 2006
- Authors: Ngcibi, Sakhile Leonard
- Date: 2006
- Subjects: Abelian groups Fuzzy sets Finite groups Group theory Polynomials
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5416 , http://hdl.handle.net/10962/d1005230
- Description: We determine the number and nature of distinct equivalence classes of fuzzy subgroups of finite Abelian p-group G of rank two under a natural equivalence relation on fuzzy subgroups. Our discussions embrace the necessary theory from groups with special emphasis on finite p-groups as a step towards the classification of crisp subgroups as well as maximal chains of subgroups. Unique naming of subgroup generators as discussed in this work facilitates counting of subgroups and chains of subgroups from subgroup lattices of the groups. We cover aspects of fuzzy theory including fuzzy (homo-) isomorphism together with operations on fuzzy subgroups. The equivalence characterization as discussed here is finer than isomorphism. We introduce the theory of keychains with a view towards the enumeration of maximal chains as well as fuzzy subgroups under the equivalence relation mentioned above. We discuss a strategy to develop subgroup lattices of the groups used in the discussion, and give examples for specific cases of prime p and positive integers n,m. We derive formulas for both the number of maximal chains as well as the number of distinct equivalence classes of fuzzy subgroups. The results are in the form of polynomials in p (known in the literature as Hall polynomials) with combinatorial coefficients. Finally we give a brief investigation of the results from a graph-theoretic point of view. We view the subgroup lattices of these groups as simple, connected, symmetric graphs.
- Full Text:
- Date Issued: 2006
Teachers as recontextualisers: a case study analysis of outcomes-based assessment policy implementation in two South African schools
- Authors: Wilmot, Pamela Dianne
- Date: 2006
- Subjects: Competency-based education -- South Africa Competency-based education -- South Africa -- Case studies Educational change -- South Africa Teacher participation in curriculum planning -- South Africa Teachers -- Training of -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1792 , http://hdl.handle.net/10962/d1003677
- Description: The research presented in this thesis is a case study analysis of outcomes-based assessment in Grade 9 Human and Social Sciences of Curriculum 2005 in two South African schools. The research consists of two parts: Phase One, 2002 to 2003, was a qualitative case study, interpretive in orientation and using ethnographic techniques, aimed at understanding teachers’ responses to curriculum policy and the role of a school-based intervention, located within critically reflexive practice, in supporting change. During this phase, I was a co-participant operating from an insider position. During Phase Two, 2004-2005, I withdrew from the schools and took up an outsider position in order to analyse and theorise the case study. The findings of the interpretive review revealed a fascinating process of change, with some unexpected results that I lacked the theoretical and methodological tools to process. With support from critical friends, I realised that a dynamic and social process of knowledge recontextualisation had taken place, and that the research had moved beyond its initial goals. Not wishing to compromise my integrity as a qualitative researcher, I changed direction and made use of Basil Bernstein’s theorising (1990, 1996) to arrive at a suitable vantage point for the analysis. The main contention of this thesis is that the new OBE curriculum framework offers exciting opportunities for teacher participation in curriculum processes. However, if teachers are to maximise these and become agents of change, they need to acquire the rules of recontextualisation and reposition themselves in the recontextualising field. This implies epistemological empowerment, which takes time and mediation but which can be achieved through an approach to teacher professional development located in critically reflexive practice.
- Full Text:
- Date Issued: 2006
- Authors: Wilmot, Pamela Dianne
- Date: 2006
- Subjects: Competency-based education -- South Africa Competency-based education -- South Africa -- Case studies Educational change -- South Africa Teacher participation in curriculum planning -- South Africa Teachers -- Training of -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1792 , http://hdl.handle.net/10962/d1003677
- Description: The research presented in this thesis is a case study analysis of outcomes-based assessment in Grade 9 Human and Social Sciences of Curriculum 2005 in two South African schools. The research consists of two parts: Phase One, 2002 to 2003, was a qualitative case study, interpretive in orientation and using ethnographic techniques, aimed at understanding teachers’ responses to curriculum policy and the role of a school-based intervention, located within critically reflexive practice, in supporting change. During this phase, I was a co-participant operating from an insider position. During Phase Two, 2004-2005, I withdrew from the schools and took up an outsider position in order to analyse and theorise the case study. The findings of the interpretive review revealed a fascinating process of change, with some unexpected results that I lacked the theoretical and methodological tools to process. With support from critical friends, I realised that a dynamic and social process of knowledge recontextualisation had taken place, and that the research had moved beyond its initial goals. Not wishing to compromise my integrity as a qualitative researcher, I changed direction and made use of Basil Bernstein’s theorising (1990, 1996) to arrive at a suitable vantage point for the analysis. The main contention of this thesis is that the new OBE curriculum framework offers exciting opportunities for teacher participation in curriculum processes. However, if teachers are to maximise these and become agents of change, they need to acquire the rules of recontextualisation and reposition themselves in the recontextualising field. This implies epistemological empowerment, which takes time and mediation but which can be achieved through an approach to teacher professional development located in critically reflexive practice.
- Full Text:
- Date Issued: 2006
The 'global' and the 'local' : a comparative study of development practices in three South African municipalities
- Authors: Gibb, Matthew William
- Date: 2013-08-15
- Subjects: Ndlambe Municipality Emalahleni Municipality Cape Town Municipality Local government -- South Africa Poor -- South Africa Globalization Economic development -- South Africa Community development -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4871 , http://hdl.handle.net/10962/d1008413
- Description: On first impression, it would seem that globalisation is producing an increasingly homogenous trans-border world, whereby, as a result of key changes including the impact of technological improvements, foreign travel, the spread of westernised cultural identities, market capitalism, and liberal democracy, the point has been reached where it is now becoming difficult to tell different localities apart. In this process, it is often forgotten what role individual places assume in the creation of this globalised world and that not all will benefit from globalisation. In many respects, locally specific activities, including urban renewal, place promotion, and infrastructural developments pursued within a selection of the planet's most strategically connected cities are now the primary catalysts of, and the influence behind, globalisation. Likewise, community-businesses, rural micro-industries, and alternative livelihoods are some of the key mechanisms that under-privileged localities in developing countries are employing to either respond to the marginalization imposed by globalisation, or to simply ensure survival. The emergence of localisation theory has therefore acknowledged and exemplified the importance of the locality in the context of the global economy as either a key node within it or a point within which people must engage in coping strategies, often as a result of the negative impacts of globalisation. In recent years, varying styles of locality-based development have become central to enhancing both the pro-growth global competitiveness of a number of South African localities, as well as for initiating pro-poor interventions in several of the country's smaller towns and rural areas. In the City of Cape Town, millions of Rands have been invested by the municipality and the private sector in urban regeneration strategies,which have led to an economic rebirth in the city centre and have generated numerous jobs in the tertiary and construction sectors that have helped to enhance the city's global stature. In Ndlambe Municipality, two community-businesses, which have received national funding and have strong municipal support, employ fifty people between them and have demonstrated the advantages of participatory action in propoor local development, within the context of the open market. In Emalahleni Municipality, attempts at locality-based development have been instigated directly by the local poor themselves and have been organised by members of the community in the face of non-existent local government support, which have resulted in the creation of several hundred income-earning opportunities for area residents. In summary, these three cases illustrate a range of approaches to locality-based development cunently undertaken in South Africa by different localities possessing widely differing resources, skills, and degrees of global connectivity in order to initiate growth and enhance standards of living. From a theoretical perspective this study provides a South African slant on global theories and processes and further indicates the role that a series of localities in the South are playing in a changing global system. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Gibb, Matthew William
- Date: 2013-08-15
- Subjects: Ndlambe Municipality Emalahleni Municipality Cape Town Municipality Local government -- South Africa Poor -- South Africa Globalization Economic development -- South Africa Community development -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4871 , http://hdl.handle.net/10962/d1008413
- Description: On first impression, it would seem that globalisation is producing an increasingly homogenous trans-border world, whereby, as a result of key changes including the impact of technological improvements, foreign travel, the spread of westernised cultural identities, market capitalism, and liberal democracy, the point has been reached where it is now becoming difficult to tell different localities apart. In this process, it is often forgotten what role individual places assume in the creation of this globalised world and that not all will benefit from globalisation. In many respects, locally specific activities, including urban renewal, place promotion, and infrastructural developments pursued within a selection of the planet's most strategically connected cities are now the primary catalysts of, and the influence behind, globalisation. Likewise, community-businesses, rural micro-industries, and alternative livelihoods are some of the key mechanisms that under-privileged localities in developing countries are employing to either respond to the marginalization imposed by globalisation, or to simply ensure survival. The emergence of localisation theory has therefore acknowledged and exemplified the importance of the locality in the context of the global economy as either a key node within it or a point within which people must engage in coping strategies, often as a result of the negative impacts of globalisation. In recent years, varying styles of locality-based development have become central to enhancing both the pro-growth global competitiveness of a number of South African localities, as well as for initiating pro-poor interventions in several of the country's smaller towns and rural areas. In the City of Cape Town, millions of Rands have been invested by the municipality and the private sector in urban regeneration strategies,which have led to an economic rebirth in the city centre and have generated numerous jobs in the tertiary and construction sectors that have helped to enhance the city's global stature. In Ndlambe Municipality, two community-businesses, which have received national funding and have strong municipal support, employ fifty people between them and have demonstrated the advantages of participatory action in propoor local development, within the context of the open market. In Emalahleni Municipality, attempts at locality-based development have been instigated directly by the local poor themselves and have been organised by members of the community in the face of non-existent local government support, which have resulted in the creation of several hundred income-earning opportunities for area residents. In summary, these three cases illustrate a range of approaches to locality-based development cunently undertaken in South Africa by different localities possessing widely differing resources, skills, and degrees of global connectivity in order to initiate growth and enhance standards of living. From a theoretical perspective this study provides a South African slant on global theories and processes and further indicates the role that a series of localities in the South are playing in a changing global system. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
The development and application of ecological risk assessment in South African water resource management
- Authors: Claassen, Marius
- Date: 2006
- Subjects: Ecological risk assessment -- South Africa Water resources development -- South Africa Water quality management -- South Africa Water-supply -- Management -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6036 , http://hdl.handle.net/10962/d1006177
- Description: The provision of goods and services by aquatic ecosystems plays an important role in socio-economic development and livelihoods in the southern African region. Water resource management in South Africa developed from an agrarian and pastoral focus up to 1956 to also supporting mining and industrial activities. This led to the introduction of the resource water quality objectives and pollution prevention approaches, which balanced the needs for development and protection. Prior to 1994, access to water resources was limited to riparian property owners and a minority of the population who controlled industrial and mining activities. The establishment of a democratic government amplified the need for accelerated socio-economic development, with equity, efficiency and sustainability being the principles of such development. New approaches were needed, which could achieve these development objectives and secure the resource base for future generations. An overview of the scientific process highlighted a risk based approach as potentially supporting the much needed balance between development and protection. The aims of this thesis is to develop a framework and process for the application of ecological risk assessment to water resource management in South Africa, to use case studies to draft guidelines for ecological risk assessment and to assess the degree to which ecological risk assessment can contribute to effective water resource management in South Africa. The United States Environmental Protection Agency’s guidelines for ecological risk assessment were identified amongst international best practice as meeting the requirements for local application. A framework was drafted for ecological risk assessment in South Africa, with the main phases being to agree on objectives, formulate the analysis plan, analyse information, characterise risk and manage risk. Modifications from the Environmental Protection Agency’s process include the order of activities in the first phase, the explicit testing of hypotheses and clarification of the evaluation of existing data or collection of new data. An industrial effluent case study was used to assess the applicability of the proposed framework. The case study dealt specifically with the assessment of risks posed by current conditions and long term licence conditions. The framework was found to be useful to identify weaknesses in the established monitoring programme and to evaluate lines of evidence to assess the degree to which the stated conditions would have unacceptable consequences. The study highlighted several weaknesses in the suggested framework, of which the most critical is the interpretation of the risk hypothesis as a testable null hypothesis. It became clear that cause-effect relationships should be stated as the risk hypothesis, whereas the assessment should evaluate expressed or expected conditions against a risk profile for a given stressor to benefit fully from the risk assessment approach. Changes to the framework terminology were suggested as well as nested feedback loops to allow for iterative processes where new information becomes available. The proposed guidelines incorporate the learning from the case study application as well as feedback from a peer review process. The guidelines incorporate the suggested actions under each phase as well as notes providing the rationale for each step. Three case study outlines were provided to assist users with the interpretation of the guidelines in different applications. The proposed guidelines are applied in an ecological Reserve determination case study, which specified the ecological water quality requirements. The study found that a risk-based approach was followed in the development of the water resource management policy, but the Reserve determination method is generally hazard based, with site specific modifications of the target values being allowed on a conservative basis. The case study highlighted a lack of readiness of water resource managers to accommodate scientific results expressed as probability distributions in support of management decisions. The thesis is concluded with a discussion of the key learning points of the ecological risk assessment development process. The evaluation highlights the move from stating and testing a null hypothesis to stating the risk hypothesis and evaluating the stated conditions against a risk profile. Several implementation challenges are highlighted, with specific recommendations made for adopting the proposed guidelines.
- Full Text:
- Date Issued: 2006
- Authors: Claassen, Marius
- Date: 2006
- Subjects: Ecological risk assessment -- South Africa Water resources development -- South Africa Water quality management -- South Africa Water-supply -- Management -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6036 , http://hdl.handle.net/10962/d1006177
- Description: The provision of goods and services by aquatic ecosystems plays an important role in socio-economic development and livelihoods in the southern African region. Water resource management in South Africa developed from an agrarian and pastoral focus up to 1956 to also supporting mining and industrial activities. This led to the introduction of the resource water quality objectives and pollution prevention approaches, which balanced the needs for development and protection. Prior to 1994, access to water resources was limited to riparian property owners and a minority of the population who controlled industrial and mining activities. The establishment of a democratic government amplified the need for accelerated socio-economic development, with equity, efficiency and sustainability being the principles of such development. New approaches were needed, which could achieve these development objectives and secure the resource base for future generations. An overview of the scientific process highlighted a risk based approach as potentially supporting the much needed balance between development and protection. The aims of this thesis is to develop a framework and process for the application of ecological risk assessment to water resource management in South Africa, to use case studies to draft guidelines for ecological risk assessment and to assess the degree to which ecological risk assessment can contribute to effective water resource management in South Africa. The United States Environmental Protection Agency’s guidelines for ecological risk assessment were identified amongst international best practice as meeting the requirements for local application. A framework was drafted for ecological risk assessment in South Africa, with the main phases being to agree on objectives, formulate the analysis plan, analyse information, characterise risk and manage risk. Modifications from the Environmental Protection Agency’s process include the order of activities in the first phase, the explicit testing of hypotheses and clarification of the evaluation of existing data or collection of new data. An industrial effluent case study was used to assess the applicability of the proposed framework. The case study dealt specifically with the assessment of risks posed by current conditions and long term licence conditions. The framework was found to be useful to identify weaknesses in the established monitoring programme and to evaluate lines of evidence to assess the degree to which the stated conditions would have unacceptable consequences. The study highlighted several weaknesses in the suggested framework, of which the most critical is the interpretation of the risk hypothesis as a testable null hypothesis. It became clear that cause-effect relationships should be stated as the risk hypothesis, whereas the assessment should evaluate expressed or expected conditions against a risk profile for a given stressor to benefit fully from the risk assessment approach. Changes to the framework terminology were suggested as well as nested feedback loops to allow for iterative processes where new information becomes available. The proposed guidelines incorporate the learning from the case study application as well as feedback from a peer review process. The guidelines incorporate the suggested actions under each phase as well as notes providing the rationale for each step. Three case study outlines were provided to assist users with the interpretation of the guidelines in different applications. The proposed guidelines are applied in an ecological Reserve determination case study, which specified the ecological water quality requirements. The study found that a risk-based approach was followed in the development of the water resource management policy, but the Reserve determination method is generally hazard based, with site specific modifications of the target values being allowed on a conservative basis. The case study highlighted a lack of readiness of water resource managers to accommodate scientific results expressed as probability distributions in support of management decisions. The thesis is concluded with a discussion of the key learning points of the ecological risk assessment development process. The evaluation highlights the move from stating and testing a null hypothesis to stating the risk hypothesis and evaluating the stated conditions against a risk profile. Several implementation challenges are highlighted, with specific recommendations made for adopting the proposed guidelines.
- Full Text:
- Date Issued: 2006
The development and assessment of a generic carbamazepine sustained release dosage form
- Authors: Patel, Fathima
- Date: 2006
- Subjects: Carbamazepine Pharmacokinetics Drugs -- Controlled release Drugs -- Dosage forms Tablets (Medicine) Drugs -- Administration
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3784 , http://hdl.handle.net/10962/d1003262
- Description: Carbamazepine (CBZ) is a first-line drug used for the treatment of partial and tonic-clonic seizures. It is also the drug of choice for use during pregnancy and recommended for the treatment of seizure disorders in children. CBZ possesses the ability to induce metabolism of drugs that are transformed in the liver and has the unique ability to induce its own metabolism by a phenomenon known as ‘auto- induction’, where its biological half-life is significantly reduced during chronic administration. Large doses of CBZ are often prescribed as daily divided doses and this often adversely affects patient compliance, with the result that therapy is ineffective. A sustained-release dosage form containing CBZ is currently marketed as Tegretol® CR and the development of a generic product would provide patients with an equivalent product with a similar dosing frequency, at a reduced cost. Therefore, the development of a polymer-based matrix tablet was undertaken to produce a sustained-release dosage form of CBZ, since these dosage forms are relatively simple and cheap to produce when compared to other, more sophisticated forms of sustained-release technology. Preformulation studies were conducted to assess moisture content of excipients and dosage forms and to identify possible incompatibilities between CBZ and potential formulation excipients. Furthermore, studies were conducted to assess the potential for polymorphic transitions to occur during manufacture. Stability testing was conducted to assess the behaviour of the dosage forms under storage conditions that the product may be exposed to. Dissolution testing was undertaken using USP Apparatus 3, which allowed for a more realistic assessment and prediction of in vivo drug release rates. Samples were analysed using a high performance liquid chromatographic method that was developed and validated for the determination of CBZ. Tablets were manufactured by wet granulation and direct compression techniques, and the resultant drug release profiles were evaluated statistically by means of the f1 and f2 difference and similarity factors. The f2 factor was incorporated as an assessment criterion in the design of an artificial neural network that was used to predict drug release profiles and formulation composition. A direct compression tablet formulation was successfully adapted from a prototype wet granulation matrix formulation and a number of formulation variables were assessed to establish their effect(s) on the dissolution rate profile of CBZ that resulted from testing of the dosage forms. The particle size grade of CBZ was also investigated and it was ascertained that fine particle size grade CBZ showed improved drug release profiles when compared to the coarse grade CBZ which was desirable, since CBZ is a highly water insoluble compound. Furthermore, the impact of the viscosity grade and proportion of rate-controlling polymer, viz., hydroxypropyl methylcellulose was also investigated for its effect on drug release rates. The lower viscosity grade was found to be more appropriate for use with CBZ. The type of anti-frictional agent used in the formulations did not appear to affect drug release from the polymeric matrix tablets, however specific compounds may have an effect on the physical characteristics of the polymeric tablets. The resultant formulations did not display zero-order drug release kinetics and a first-order mathematical model was developed to provide an additional resource for athematical analysis of dissolution profiles. An artificial neural network was designed, developed and applied to predict dissolution rate profiles for formulation. Furthermore, the network was used to predict formulation compositions that would produce drug release profiles comparable to the reference product, Tegretol® CR. The formulation composition predicted by the network to match the dissolution profile of the innovator product was manufactured and tested in vitro. The formulation was further manipulated, empirically, so as to match the in vitro dissolution rate profile of Tegretol® CR, more completely. The test tablets that were produced were tested in two health male volunteers using Tegretol® CR 400mg as the reference product. The batch used for this “proof of concept” biostudy was produced in accordance with cGMP guidelines and the protocol in accordance with ICH guidelines. The test matrix tablets revealed in vivo bioavailability profiles for CBZ, however, bioequivalence between the test and reference product could not be established. It can be concluded that the polymeric matrix CBZ tablets have the potential to be used as a twice-daily dosage form for the treatment of relevant seizure disorders.
- Full Text:
- Date Issued: 2006
- Authors: Patel, Fathima
- Date: 2006
- Subjects: Carbamazepine Pharmacokinetics Drugs -- Controlled release Drugs -- Dosage forms Tablets (Medicine) Drugs -- Administration
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3784 , http://hdl.handle.net/10962/d1003262
- Description: Carbamazepine (CBZ) is a first-line drug used for the treatment of partial and tonic-clonic seizures. It is also the drug of choice for use during pregnancy and recommended for the treatment of seizure disorders in children. CBZ possesses the ability to induce metabolism of drugs that are transformed in the liver and has the unique ability to induce its own metabolism by a phenomenon known as ‘auto- induction’, where its biological half-life is significantly reduced during chronic administration. Large doses of CBZ are often prescribed as daily divided doses and this often adversely affects patient compliance, with the result that therapy is ineffective. A sustained-release dosage form containing CBZ is currently marketed as Tegretol® CR and the development of a generic product would provide patients with an equivalent product with a similar dosing frequency, at a reduced cost. Therefore, the development of a polymer-based matrix tablet was undertaken to produce a sustained-release dosage form of CBZ, since these dosage forms are relatively simple and cheap to produce when compared to other, more sophisticated forms of sustained-release technology. Preformulation studies were conducted to assess moisture content of excipients and dosage forms and to identify possible incompatibilities between CBZ and potential formulation excipients. Furthermore, studies were conducted to assess the potential for polymorphic transitions to occur during manufacture. Stability testing was conducted to assess the behaviour of the dosage forms under storage conditions that the product may be exposed to. Dissolution testing was undertaken using USP Apparatus 3, which allowed for a more realistic assessment and prediction of in vivo drug release rates. Samples were analysed using a high performance liquid chromatographic method that was developed and validated for the determination of CBZ. Tablets were manufactured by wet granulation and direct compression techniques, and the resultant drug release profiles were evaluated statistically by means of the f1 and f2 difference and similarity factors. The f2 factor was incorporated as an assessment criterion in the design of an artificial neural network that was used to predict drug release profiles and formulation composition. A direct compression tablet formulation was successfully adapted from a prototype wet granulation matrix formulation and a number of formulation variables were assessed to establish their effect(s) on the dissolution rate profile of CBZ that resulted from testing of the dosage forms. The particle size grade of CBZ was also investigated and it was ascertained that fine particle size grade CBZ showed improved drug release profiles when compared to the coarse grade CBZ which was desirable, since CBZ is a highly water insoluble compound. Furthermore, the impact of the viscosity grade and proportion of rate-controlling polymer, viz., hydroxypropyl methylcellulose was also investigated for its effect on drug release rates. The lower viscosity grade was found to be more appropriate for use with CBZ. The type of anti-frictional agent used in the formulations did not appear to affect drug release from the polymeric matrix tablets, however specific compounds may have an effect on the physical characteristics of the polymeric tablets. The resultant formulations did not display zero-order drug release kinetics and a first-order mathematical model was developed to provide an additional resource for athematical analysis of dissolution profiles. An artificial neural network was designed, developed and applied to predict dissolution rate profiles for formulation. Furthermore, the network was used to predict formulation compositions that would produce drug release profiles comparable to the reference product, Tegretol® CR. The formulation composition predicted by the network to match the dissolution profile of the innovator product was manufactured and tested in vitro. The formulation was further manipulated, empirically, so as to match the in vitro dissolution rate profile of Tegretol® CR, more completely. The test tablets that were produced were tested in two health male volunteers using Tegretol® CR 400mg as the reference product. The batch used for this “proof of concept” biostudy was produced in accordance with cGMP guidelines and the protocol in accordance with ICH guidelines. The test matrix tablets revealed in vivo bioavailability profiles for CBZ, however, bioequivalence between the test and reference product could not be established. It can be concluded that the polymeric matrix CBZ tablets have the potential to be used as a twice-daily dosage form for the treatment of relevant seizure disorders.
- Full Text:
- Date Issued: 2006
The development of an entrepreneurial management model to promote the survival and growth of family estate wine businesses in the South African wine industry
- Cullen, Margaret Diane Munro
- Authors: Cullen, Margaret Diane Munro
- Date: 2006
- Subjects: Family-owned business enterprises -- South Africa , Wine industry -- South Africa -- Management , Entrepreneurship
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8766 , http://hdl.handle.net/10948/491 , http://hdl.handle.net/10948/d1011909 , Family-owned business enterprises -- South Africa , Wine industry -- South Africa -- Management , Entrepreneurship
- Description: The South African wine industry is polarised into the quantity-producing majority and the quality-conscious minority [Hughes, 2003]. The qualityproducing sector of the South African wine industry is dominated by family businesses. Research shows that there are approximately ninety familyowned wineries in South Africa. By international standards, South Africa is viewed as a quantity, not quality producing wine country, which will make it difficult to survive in an industry where quality is paramount for recognition. The ‘trailblazers’ of the international wine industry are family owned wineries [Robinson, 2000]. Twenty five percent of the 2003 five star South African wines were made by individuals or family wineries [Hughes, 2003], emphasising the growing importance of family wineries in the production of quality wines. It is important now, more than ever, with the industry opening up internationally, that survival of the family-owned wineries and their production of icon wines are promoted so that they can become flagship producers of the industry. The achievement of international status as a quality producing country, as well as building an industry based on the longevity of wine producing families, as well as a nation of wine lovers in South Africa should result.
- Full Text:
- Date Issued: 2006
- Authors: Cullen, Margaret Diane Munro
- Date: 2006
- Subjects: Family-owned business enterprises -- South Africa , Wine industry -- South Africa -- Management , Entrepreneurship
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8766 , http://hdl.handle.net/10948/491 , http://hdl.handle.net/10948/d1011909 , Family-owned business enterprises -- South Africa , Wine industry -- South Africa -- Management , Entrepreneurship
- Description: The South African wine industry is polarised into the quantity-producing majority and the quality-conscious minority [Hughes, 2003]. The qualityproducing sector of the South African wine industry is dominated by family businesses. Research shows that there are approximately ninety familyowned wineries in South Africa. By international standards, South Africa is viewed as a quantity, not quality producing wine country, which will make it difficult to survive in an industry where quality is paramount for recognition. The ‘trailblazers’ of the international wine industry are family owned wineries [Robinson, 2000]. Twenty five percent of the 2003 five star South African wines were made by individuals or family wineries [Hughes, 2003], emphasising the growing importance of family wineries in the production of quality wines. It is important now, more than ever, with the industry opening up internationally, that survival of the family-owned wineries and their production of icon wines are promoted so that they can become flagship producers of the industry. The achievement of international status as a quality producing country, as well as building an industry based on the longevity of wine producing families, as well as a nation of wine lovers in South Africa should result.
- Full Text:
- Date Issued: 2006
The economic valuation of cultural events in developing countries: combining market and non-market valuation techniques at the South African National Arts Festival
- Authors: Snowball, Jeanette Dalziel
- Date: 2006
- Subjects: Standard Bank National Arts Festival -- Economic aspects , Performing arts festivals -- Economic aspects -- South Africa -- Grahamstown , Arts -- South Africa -- Economic aspects , Finance -- South Africa , Arts -- South Africa -- Finance , Arts -- South Africa -- Political aspects , Finance, Public -- South Africa , South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:969 , http://hdl.handle.net/10962/d1002703 , Standard Bank National Arts Festival -- Economic aspects , Performing arts festivals -- Economic aspects -- South Africa -- Grahamstown , Arts -- South Africa -- Economic aspects , Finance -- South Africa , Arts -- South Africa -- Finance , Arts -- South Africa -- Political aspects , Finance, Public -- South Africa , South Africa -- Politics and government -- 1994-
- Description: The arts in many countries, but particularly in developing ones, are coming under increasing financial pressure and finding it difficult to justify the increases in government funding needed to maintain and grow the cultural sector. The trend in cultural economics, as well as in other areas, appears to be towards including qualitative valuations, as well as the more traditional quantitative ones. This thesis argues that the value of cultural events should include long term historical qualitative analysis, financial or economic impact and a valuation of the positive externalities provided by cultural events and that any one of these should only be regarded as a partial analysis. Four methods of valuing the arts using the South African National Arts Festival (NAF) as an example are demonstrated. Firstly, a qualitative historical analysis of the role of the NAF in South Africa’s transformation process from Apartheid to the democratic New South Africa is examined, using theories of cultural capital as a theoretical basis. It is argued that the value of cultural events needs to take into account long-term influences especially in countries undergoing political and social transformation. The second valuation method applied is the traditional economic impact study. Four economic impact studies conducted on the NAF are discussed and methodologies compared. It is concluded that, despite the skepticism of many cultural economists, the method can provide a useful partial valuation and may also be used for effective lobbying for government support of the arts. Chapter four discusses willingness to pay studies conducted at the NAF in 2000 and 2003 (as well as a pilot study conducted at the Klein Karoo Nationale Kunstefees). It is found that lower income and education groups do benefit from the positive externalities provided by the Festival and that this is reflected in their willingness to pay to support it. It is also argued that such contingent valuation studies can provide a reasonably reliable valuation of Festival externalities, but that they may be partly capturing current or future expected financial gains as well. Finally, the relatively new choice experiment methodology (also called conjoint analysis) is demonstrated on visitors to the NAF. The great advantage of this method in valuing cultural events is that it provides part-worths of various Festival attributes for different demographic groups. This enables organizes to structure the programme in such a way as to attract previously excluded groups and to conduct a cost-benefit analysis for each part of the Festival.
- Full Text:
- Date Issued: 2006
- Authors: Snowball, Jeanette Dalziel
- Date: 2006
- Subjects: Standard Bank National Arts Festival -- Economic aspects , Performing arts festivals -- Economic aspects -- South Africa -- Grahamstown , Arts -- South Africa -- Economic aspects , Finance -- South Africa , Arts -- South Africa -- Finance , Arts -- South Africa -- Political aspects , Finance, Public -- South Africa , South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:969 , http://hdl.handle.net/10962/d1002703 , Standard Bank National Arts Festival -- Economic aspects , Performing arts festivals -- Economic aspects -- South Africa -- Grahamstown , Arts -- South Africa -- Economic aspects , Finance -- South Africa , Arts -- South Africa -- Finance , Arts -- South Africa -- Political aspects , Finance, Public -- South Africa , South Africa -- Politics and government -- 1994-
- Description: The arts in many countries, but particularly in developing ones, are coming under increasing financial pressure and finding it difficult to justify the increases in government funding needed to maintain and grow the cultural sector. The trend in cultural economics, as well as in other areas, appears to be towards including qualitative valuations, as well as the more traditional quantitative ones. This thesis argues that the value of cultural events should include long term historical qualitative analysis, financial or economic impact and a valuation of the positive externalities provided by cultural events and that any one of these should only be regarded as a partial analysis. Four methods of valuing the arts using the South African National Arts Festival (NAF) as an example are demonstrated. Firstly, a qualitative historical analysis of the role of the NAF in South Africa’s transformation process from Apartheid to the democratic New South Africa is examined, using theories of cultural capital as a theoretical basis. It is argued that the value of cultural events needs to take into account long-term influences especially in countries undergoing political and social transformation. The second valuation method applied is the traditional economic impact study. Four economic impact studies conducted on the NAF are discussed and methodologies compared. It is concluded that, despite the skepticism of many cultural economists, the method can provide a useful partial valuation and may also be used for effective lobbying for government support of the arts. Chapter four discusses willingness to pay studies conducted at the NAF in 2000 and 2003 (as well as a pilot study conducted at the Klein Karoo Nationale Kunstefees). It is found that lower income and education groups do benefit from the positive externalities provided by the Festival and that this is reflected in their willingness to pay to support it. It is also argued that such contingent valuation studies can provide a reasonably reliable valuation of Festival externalities, but that they may be partly capturing current or future expected financial gains as well. Finally, the relatively new choice experiment methodology (also called conjoint analysis) is demonstrated on visitors to the NAF. The great advantage of this method in valuing cultural events is that it provides part-worths of various Festival attributes for different demographic groups. This enables organizes to structure the programme in such a way as to attract previously excluded groups and to conduct a cost-benefit analysis for each part of the Festival.
- Full Text:
- Date Issued: 2006
The investigation, development and characterisation of novel zirconium-based tanning agents
- Guthrie-Strachan, Jeffry James
- Authors: Guthrie-Strachan, Jeffry James
- Date: 2006
- Subjects: Zirconium Tanning Leather
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4319 , http://hdl.handle.net/10962/d1004977
- Description: Various oxygen- and nitrogen-donor ligands were investigated as potential zirconium masking agents in zirconium tanning. α-Hydroxycarboxylic acid ligands were identified as effective zirconium(IV) chelators in acidic aqueous solution. Glycolic acid, lactic acid, mandelic acid, 4-hydroxymandelic acid, 4-chloromandelic acid and 4-bromomandelic acid complexes were synthesised, isolated and characterised using a range of analytical techniques. Linear Free Energy Relationships were examined to optimise the stability of the zirconium complexes. Hammett [sigma] plots and Yukawa-Tsuno modified σ plots of the mandelate ligand and zirconium complex series indicated that inductive effects dominate within the benzene ring, however, mesomeric effects are significant outside the ring. Zirconium 4-hydroxymandelate complex solutions were identified as the most effective tanning agents and achieved shrinkage temperatures of 80 and 97ºC for hide powder and goatskin, respectively. The zirconium and 4-hydroxymandelic acid interact synergistically to yield leather equivalent to combination tanned leather in one step. Tanning was performed similarly to vegetable tanning processes with a pickle pH of approximately 5 and fixation was achieved upon acidification. Pilot-scale tanning of goatskin produced white tanned leathers and crust leathers which were physically and aesthetically comparable to matched chromium tanned material.
- Full Text:
- Date Issued: 2006
- Authors: Guthrie-Strachan, Jeffry James
- Date: 2006
- Subjects: Zirconium Tanning Leather
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4319 , http://hdl.handle.net/10962/d1004977
- Description: Various oxygen- and nitrogen-donor ligands were investigated as potential zirconium masking agents in zirconium tanning. α-Hydroxycarboxylic acid ligands were identified as effective zirconium(IV) chelators in acidic aqueous solution. Glycolic acid, lactic acid, mandelic acid, 4-hydroxymandelic acid, 4-chloromandelic acid and 4-bromomandelic acid complexes were synthesised, isolated and characterised using a range of analytical techniques. Linear Free Energy Relationships were examined to optimise the stability of the zirconium complexes. Hammett [sigma] plots and Yukawa-Tsuno modified σ plots of the mandelate ligand and zirconium complex series indicated that inductive effects dominate within the benzene ring, however, mesomeric effects are significant outside the ring. Zirconium 4-hydroxymandelate complex solutions were identified as the most effective tanning agents and achieved shrinkage temperatures of 80 and 97ºC for hide powder and goatskin, respectively. The zirconium and 4-hydroxymandelic acid interact synergistically to yield leather equivalent to combination tanned leather in one step. Tanning was performed similarly to vegetable tanning processes with a pickle pH of approximately 5 and fixation was achieved upon acidification. Pilot-scale tanning of goatskin produced white tanned leathers and crust leathers which were physically and aesthetically comparable to matched chromium tanned material.
- Full Text:
- Date Issued: 2006
The poetry of N.H. Brettell : a critical edition
- Authors: Hacksley, Reginald Gregory
- Date: 2006
- Subjects: Brettell, N H -- Criticism and interpretation South African poetry (English) -- History and criticism
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2289 , http://hdl.handle.net/10962/d1008072
- Description: This thesis presents for the first time a critical reading edition of all known poems by N. H. Brettell. It makes no claim to being definitive, nor does it attempt to establish a final text. It represents merely the best thinking of the editor. Brettell printed and circulated his poetry primarily in hand-made illustrated volumes in a process reminiscent of the scribal publication of the seventeenth century. Only 137 of his 206 extant poems were commercially published during his lifetime. In this study all known printed versions of Brettell's poetry whether in privately printed or commercially published form were examined. All variant readings were recorded and are shown. Wherever possible the relationships between texts are also noted. The poems in this edition are ordered in each case according to the version in the latest datable privately produced collection. The commentary and critical introduction were compiled with the general reader in mind. No previous familiarity with southern African fauna and flora is assumed: animals, birds and insects are described and their scientific names supplied. Expressions current in ordinary British or South African English and present in non-specialist dictionaries are not glossed, but archaic and dialectal forms felt to require explication are briefly explained. So too are less familiar South African dialectal expressions which have been assimilated into the South African English lexicon. Intertextual, Christian and mythological references, both African and Western, are annotated in an attempt to make such references accessible to readers who may not share Brettell's cultural background. The intention is to close the changing distance between the text and the audience. An essay discussing the merits, potential and limitations of electronic scholarly editing is included as part of the textual introduction. A CD-Rom containing Brettell's watercolour illustrations in his privately produced collections and audio-clips of him reading his poetry accompanies this thesis.
- Full Text:
- Date Issued: 2006
- Authors: Hacksley, Reginald Gregory
- Date: 2006
- Subjects: Brettell, N H -- Criticism and interpretation South African poetry (English) -- History and criticism
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2289 , http://hdl.handle.net/10962/d1008072
- Description: This thesis presents for the first time a critical reading edition of all known poems by N. H. Brettell. It makes no claim to being definitive, nor does it attempt to establish a final text. It represents merely the best thinking of the editor. Brettell printed and circulated his poetry primarily in hand-made illustrated volumes in a process reminiscent of the scribal publication of the seventeenth century. Only 137 of his 206 extant poems were commercially published during his lifetime. In this study all known printed versions of Brettell's poetry whether in privately printed or commercially published form were examined. All variant readings were recorded and are shown. Wherever possible the relationships between texts are also noted. The poems in this edition are ordered in each case according to the version in the latest datable privately produced collection. The commentary and critical introduction were compiled with the general reader in mind. No previous familiarity with southern African fauna and flora is assumed: animals, birds and insects are described and their scientific names supplied. Expressions current in ordinary British or South African English and present in non-specialist dictionaries are not glossed, but archaic and dialectal forms felt to require explication are briefly explained. So too are less familiar South African dialectal expressions which have been assimilated into the South African English lexicon. Intertextual, Christian and mythological references, both African and Western, are annotated in an attempt to make such references accessible to readers who may not share Brettell's cultural background. The intention is to close the changing distance between the text and the audience. An essay discussing the merits, potential and limitations of electronic scholarly editing is included as part of the textual introduction. A CD-Rom containing Brettell's watercolour illustrations in his privately produced collections and audio-clips of him reading his poetry accompanies this thesis.
- Full Text:
- Date Issued: 2006
The politics of transformation in South Africa: an evaluation of education policies and their implementation with particular reference to the Eastern Cape Province
- Authors: Rembe, Symphorosa Wilibald
- Date: 2006
- Subjects: Educational change -- South Africa -- Eastern Cape Education -- Political aspects -- South Africa -- Eastern Cape Education and state -- South Africa -- Eastern Cape Post-apartheid era -- South Africa South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2826 , http://hdl.handle.net/10962/d1003036
- Description: The post-apartheid government of South Africa has committed itself to achieving fundamental transformation of the education system. The government has adopted policies and measures that aimed to bring about the goals of equity and redress, and to enhance democracy and participation of all groups in development and decision making processes at all levels. It is acknowledged that the democratic government has accomplished a lot in education within this short period and has made numerous strides in enhancing equity, redress and social justice; providing high quality education for all the people of South Africa; bringing about democratisation and development; and enhancing effectiveness and efficiency. However, despite these apparent achievements, this study shows that there have been a number of setbacks and contradictions in the policies which have affected the process of bringing about fundamental changes and transformation in the education sector. The setbacks and contradictions resulted from factors which have affected the type of policies developed to transform the education sector. They also affected the formulation and implementation of the policies, thereby limiting the achievements of the goals of transformation agenda in education. Hence, this study examined the politics of transformation and change in the education sector by examining the type of policies that have been put in place; their formulation, implementation and outcome. The main research questions are: • What kind or type of policies have been put in place to transform the education sector? • How and by whom were the policies formulated? • How are these policies being implemented and what have been the outcomes of the process? Transformation and in particular the policy process is beset with continuous debate, contestation and struggle for the success of ideas and interests which are pursued by individual actors, groups and policy networks through the institutions. During these different stages policies are modified, constituted and reconstituted. As a result, they give rise to intended and unintended outcomes which are likely to support or contradict the objectives of those policies. Hence, the process cannot be explained using only one approach or theory. Therefore, this study has been situated in ideas, group and network and institutional approaches or theories to examine the factors that have affected education policies, their formulation and implementation and the overall transformation of education in South Africa. It contends that policy change and variation result from interaction of ideas and interests within patterns of group and policy networks and preset institutions. The study adopts qualitative interpretive methodology in order to question, understand and explain institutions; interests groups and ideas; socio economic and power relations involved in the process. It also appraises the framework for action. In addition to conducting literature review, unstructured interviews were held with officials from provincial and national Departments of Education, members of national and provincial legislatures, principals, teachers, members of school governing bodies, learners, Non-governmental organisations, Community based organisations, Faith based organisations, teachers’ and workers’ unions. Observations were made during meetings of school governing bodies. The study draws reference from the Eastern Cape Province between 1994 and 2002 and looks at the school level (Basic and Further Education levels). Reference is also made to selective policy instruments namely, the South African Schools Act (SASA) (1996), Curriculum 2005 and Norms and Standards for School Funding (1999). Overall, the findings of the study have shown that various factors have led to setbacks and contradictions in the policies that were adopted in education. They have also affected the formulation and implementation of the policies, hence exerting certain limitations on the achievements of the goals of transformation in education. The factors identified in the findings are the outcome of the negotiated settlement and subsequent changes made by the apartheid government in education before the 1994 elections; constraints and unequal participation of different groups in education policy development in various established structures and avenues; drawbacks in the implementation of education policies by decentralised structures and agents at various levels. This was exacerbated by lack of capacity, lack of adequate resources, lack of commitment and will among some of the civil servants coupled with corruption and mismanagement. The legacy of apartheid and the homeland governments, together with existing backlogs added another layer. Consequently, there were challenges in the economic policy which led to inadequate funding for education. The findings of this study show that competing ideas and interests advanced by groups and networks have impact on decision making, policy content and implementation. Therefore, some policies will reflect and maintain the interests of those individual actors, groups and policy networks that exerted most influence. The findings also reveal that institutional norms and rules, inadequate resources, lack of capacity and skilled human resources and economic environment, constrain decision making, policy content and implementation.
- Full Text:
- Date Issued: 2006
- Authors: Rembe, Symphorosa Wilibald
- Date: 2006
- Subjects: Educational change -- South Africa -- Eastern Cape Education -- Political aspects -- South Africa -- Eastern Cape Education and state -- South Africa -- Eastern Cape Post-apartheid era -- South Africa South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2826 , http://hdl.handle.net/10962/d1003036
- Description: The post-apartheid government of South Africa has committed itself to achieving fundamental transformation of the education system. The government has adopted policies and measures that aimed to bring about the goals of equity and redress, and to enhance democracy and participation of all groups in development and decision making processes at all levels. It is acknowledged that the democratic government has accomplished a lot in education within this short period and has made numerous strides in enhancing equity, redress and social justice; providing high quality education for all the people of South Africa; bringing about democratisation and development; and enhancing effectiveness and efficiency. However, despite these apparent achievements, this study shows that there have been a number of setbacks and contradictions in the policies which have affected the process of bringing about fundamental changes and transformation in the education sector. The setbacks and contradictions resulted from factors which have affected the type of policies developed to transform the education sector. They also affected the formulation and implementation of the policies, thereby limiting the achievements of the goals of transformation agenda in education. Hence, this study examined the politics of transformation and change in the education sector by examining the type of policies that have been put in place; their formulation, implementation and outcome. The main research questions are: • What kind or type of policies have been put in place to transform the education sector? • How and by whom were the policies formulated? • How are these policies being implemented and what have been the outcomes of the process? Transformation and in particular the policy process is beset with continuous debate, contestation and struggle for the success of ideas and interests which are pursued by individual actors, groups and policy networks through the institutions. During these different stages policies are modified, constituted and reconstituted. As a result, they give rise to intended and unintended outcomes which are likely to support or contradict the objectives of those policies. Hence, the process cannot be explained using only one approach or theory. Therefore, this study has been situated in ideas, group and network and institutional approaches or theories to examine the factors that have affected education policies, their formulation and implementation and the overall transformation of education in South Africa. It contends that policy change and variation result from interaction of ideas and interests within patterns of group and policy networks and preset institutions. The study adopts qualitative interpretive methodology in order to question, understand and explain institutions; interests groups and ideas; socio economic and power relations involved in the process. It also appraises the framework for action. In addition to conducting literature review, unstructured interviews were held with officials from provincial and national Departments of Education, members of national and provincial legislatures, principals, teachers, members of school governing bodies, learners, Non-governmental organisations, Community based organisations, Faith based organisations, teachers’ and workers’ unions. Observations were made during meetings of school governing bodies. The study draws reference from the Eastern Cape Province between 1994 and 2002 and looks at the school level (Basic and Further Education levels). Reference is also made to selective policy instruments namely, the South African Schools Act (SASA) (1996), Curriculum 2005 and Norms and Standards for School Funding (1999). Overall, the findings of the study have shown that various factors have led to setbacks and contradictions in the policies that were adopted in education. They have also affected the formulation and implementation of the policies, hence exerting certain limitations on the achievements of the goals of transformation in education. The factors identified in the findings are the outcome of the negotiated settlement and subsequent changes made by the apartheid government in education before the 1994 elections; constraints and unequal participation of different groups in education policy development in various established structures and avenues; drawbacks in the implementation of education policies by decentralised structures and agents at various levels. This was exacerbated by lack of capacity, lack of adequate resources, lack of commitment and will among some of the civil servants coupled with corruption and mismanagement. The legacy of apartheid and the homeland governments, together with existing backlogs added another layer. Consequently, there were challenges in the economic policy which led to inadequate funding for education. The findings of this study show that competing ideas and interests advanced by groups and networks have impact on decision making, policy content and implementation. Therefore, some policies will reflect and maintain the interests of those individual actors, groups and policy networks that exerted most influence. The findings also reveal that institutional norms and rules, inadequate resources, lack of capacity and skilled human resources and economic environment, constrain decision making, policy content and implementation.
- Full Text:
- Date Issued: 2006