Stakeholders' perceptions of parents' involvement in the governance of a Namibian rural school
- Authors: Niitembu, Martha M
- Date: 2007
- Subjects: School management and organization -- Namibia Education -- Parent participation -- Namibia Education and state -- Namibia Rural schools -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1770 , http://hdl.handle.net/10962/d1003655
- Description: The issue of decentralisation has been one of the top priorities of the Namibian education system since independence in 1990. One of the decentralisation aims was to enhance parental involvement in education by establishing School Boards. However, School Boards and the role of parents in school management have been considered ineffective for several years which led to the promulgation of Education Act 16 of 2001 in which the roles of School Boards are strengthened and clarified. This study sought to investigate School Board members’ perceptions, understanding and experiences of parents’ involvement in school governance more specifically after the implementation of the Education Act of 2001 in 2003. This study is an interpretive case study of one combined rural school in the Ohangwena educational region of Namibia. This research employed three data collection techniques, namely semi-structured interviews, observation and document analysis. The main findings of this study reveal that there is a lack of joint understanding and shared vision between educators and parents in the School Board. This problem underpins other more symptomatic problems, such as lack of accountability in the matter of school finances, differences in understanding the roles of School Board members and lack of parents’ motivation from the school management. The study further reveals the ineffectiveness and insufficiency of the training provided in the past. It highlights some of the challenges that hinder the effective involvement of parents in rural school governance, such as poor educational background among parents, poor knowledge of the English language and poor understanding of educational issues. However the findings also acknowledge parents’ participation and their full involvement in decision-making. The findings show that the new School Board elected in terms of the Education Act of 2001 has been more effective than previous School Boards and has reached a number of achievements such as being instrumental in solving disciplinary problems, purchasing school assets and renovating classrooms. Recommendations for practice and for further research are made.
- Full Text:
- Authors: Niitembu, Martha M
- Date: 2007
- Subjects: School management and organization -- Namibia Education -- Parent participation -- Namibia Education and state -- Namibia Rural schools -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1770 , http://hdl.handle.net/10962/d1003655
- Description: The issue of decentralisation has been one of the top priorities of the Namibian education system since independence in 1990. One of the decentralisation aims was to enhance parental involvement in education by establishing School Boards. However, School Boards and the role of parents in school management have been considered ineffective for several years which led to the promulgation of Education Act 16 of 2001 in which the roles of School Boards are strengthened and clarified. This study sought to investigate School Board members’ perceptions, understanding and experiences of parents’ involvement in school governance more specifically after the implementation of the Education Act of 2001 in 2003. This study is an interpretive case study of one combined rural school in the Ohangwena educational region of Namibia. This research employed three data collection techniques, namely semi-structured interviews, observation and document analysis. The main findings of this study reveal that there is a lack of joint understanding and shared vision between educators and parents in the School Board. This problem underpins other more symptomatic problems, such as lack of accountability in the matter of school finances, differences in understanding the roles of School Board members and lack of parents’ motivation from the school management. The study further reveals the ineffectiveness and insufficiency of the training provided in the past. It highlights some of the challenges that hinder the effective involvement of parents in rural school governance, such as poor educational background among parents, poor knowledge of the English language and poor understanding of educational issues. However the findings also acknowledge parents’ participation and their full involvement in decision-making. The findings show that the new School Board elected in terms of the Education Act of 2001 has been more effective than previous School Boards and has reached a number of achievements such as being instrumental in solving disciplinary problems, purchasing school assets and renovating classrooms. Recommendations for practice and for further research are made.
- Full Text:
Statistical analyses of artificial waterpoints: their effect on the herbaceous and woody structure composition within the Kruger National Park
- Authors: Goodall, Victoria Lucy
- Date: 2007
- Subjects: South African National Parks , Ecology -- Statistical methods , Regression analysis , Log-linear models , Game reserves -- South Africa , Kruger National Park (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5570 , http://hdl.handle.net/10962/d1002810 , South African National Parks , Ecology -- Statistical methods , Regression analysis , Log-linear models , Game reserves -- South Africa , Kruger National Park (South Africa)
- Description: The objective of this project is to link the statistical theory used in the ecological sciences with an actual project that was developed for the South African National Parks Scientific Services. It investigates the changes that have occurred in the herbaceous and woody structure due to the closure of artificial waterpoints; including the impacts that elephants and other herbivores have on the vegetation of the Kruger National Park. This project was designed in conjunction with South African National Parks (SANP) Scientific Services and it is a registered project with this department. The results of this project will be submitted to Scientific Services in accordance with the terms and conditions of a SANP research project. A major concern within the KNP is the declining numbers of rare antelope and numerous projects have been developed to investigate possible ways of halting this decline and thus protecting the heterogeneity of the Kruger National Park. Three different datasets were investigated, covering three aspects of vegetation structure and composition within the KNP. The first investigated the changes that have occurred since the N'washitsumbe enclosure in the Far Northern KNP was fenced off from the rest of the park. The results show that over the 40 years since the enclosure was built, changes have occurred which have resulted in a significant difference in the abundance of Increaser 2 and Decreaser grass species between the inside and the outside of the enclosure. Increaser 2 and Decreaser categories are the result of a grass species classification depending on whether the species thrives or is depressed by heavy grazing. The difference in grass species composition and structure between the inside and the outside of the enclosure indicates that the grazing animals within the KNP have influenced the grass composition in a way that favours the dominant animals. This has resulted in a declining roan antelope population - one of the species that is considered as a 'rare antelope'. Many artificial waterpoints (boreholes and dams) have also been closed throughout the KNP in the hope of resulting in a change in vegetation structure and composition in favour of the roan. Veld condition assessment data for 87 boreholes throughout the Park was analyzed to determine whether the veld in the vicinity is beginning to change towards a more Decreaser dominated sward which would favour the roan. The results were analyzed for the different regions of the Park; and they indicate that changes are becoming evident; however, the results are not particularly conclusive, yet. The majority of the boreholes were closed between 1994 and 1998 which means that not a lot of data were available to be analyzed. A similar study conducted in another 10 years time might reveal more meaningful results. However the results are moving in the direction hoped for by the management of the KNP. The results show that the grass composition has a higher proportion of Decreaser grasses since the closure of the waterpoints, and the grass biomass around these areas has also improved. The results were analyzed on an individual basis; and then on a regional basis as the minimal data meant that the individual analyses did not provide any significant results. A third study was then done on the impact that the rapidly increasing elephant population on the vegetation within the Riparian zone along three rivers in the Far Northern region of the KNP. The riparian zone is an important part of the landscape, in terms of providing food for many animals as well as shade. The elephant population has increased substantially since the termination of the culling program and this means that the feeding requirements of the population has increased which could result in severe damage upon the vegetation, as elephants can be very destructive feeders. The results show surprising differences between the three years of data that were analyzed; however the results indicate that the elephants are targeting specific height ranges of trees when feeding; however they do not seem to consistently target specific tree species. This is positive for the diversity of the Riparian zone as this region is very important both ecologically and aesthetically for the tourists who visit the Park.
- Full Text:
- Authors: Goodall, Victoria Lucy
- Date: 2007
- Subjects: South African National Parks , Ecology -- Statistical methods , Regression analysis , Log-linear models , Game reserves -- South Africa , Kruger National Park (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5570 , http://hdl.handle.net/10962/d1002810 , South African National Parks , Ecology -- Statistical methods , Regression analysis , Log-linear models , Game reserves -- South Africa , Kruger National Park (South Africa)
- Description: The objective of this project is to link the statistical theory used in the ecological sciences with an actual project that was developed for the South African National Parks Scientific Services. It investigates the changes that have occurred in the herbaceous and woody structure due to the closure of artificial waterpoints; including the impacts that elephants and other herbivores have on the vegetation of the Kruger National Park. This project was designed in conjunction with South African National Parks (SANP) Scientific Services and it is a registered project with this department. The results of this project will be submitted to Scientific Services in accordance with the terms and conditions of a SANP research project. A major concern within the KNP is the declining numbers of rare antelope and numerous projects have been developed to investigate possible ways of halting this decline and thus protecting the heterogeneity of the Kruger National Park. Three different datasets were investigated, covering three aspects of vegetation structure and composition within the KNP. The first investigated the changes that have occurred since the N'washitsumbe enclosure in the Far Northern KNP was fenced off from the rest of the park. The results show that over the 40 years since the enclosure was built, changes have occurred which have resulted in a significant difference in the abundance of Increaser 2 and Decreaser grass species between the inside and the outside of the enclosure. Increaser 2 and Decreaser categories are the result of a grass species classification depending on whether the species thrives or is depressed by heavy grazing. The difference in grass species composition and structure between the inside and the outside of the enclosure indicates that the grazing animals within the KNP have influenced the grass composition in a way that favours the dominant animals. This has resulted in a declining roan antelope population - one of the species that is considered as a 'rare antelope'. Many artificial waterpoints (boreholes and dams) have also been closed throughout the KNP in the hope of resulting in a change in vegetation structure and composition in favour of the roan. Veld condition assessment data for 87 boreholes throughout the Park was analyzed to determine whether the veld in the vicinity is beginning to change towards a more Decreaser dominated sward which would favour the roan. The results were analyzed for the different regions of the Park; and they indicate that changes are becoming evident; however, the results are not particularly conclusive, yet. The majority of the boreholes were closed between 1994 and 1998 which means that not a lot of data were available to be analyzed. A similar study conducted in another 10 years time might reveal more meaningful results. However the results are moving in the direction hoped for by the management of the KNP. The results show that the grass composition has a higher proportion of Decreaser grasses since the closure of the waterpoints, and the grass biomass around these areas has also improved. The results were analyzed on an individual basis; and then on a regional basis as the minimal data meant that the individual analyses did not provide any significant results. A third study was then done on the impact that the rapidly increasing elephant population on the vegetation within the Riparian zone along three rivers in the Far Northern region of the KNP. The riparian zone is an important part of the landscape, in terms of providing food for many animals as well as shade. The elephant population has increased substantially since the termination of the culling program and this means that the feeding requirements of the population has increased which could result in severe damage upon the vegetation, as elephants can be very destructive feeders. The results show surprising differences between the three years of data that were analyzed; however the results indicate that the elephants are targeting specific height ranges of trees when feeding; however they do not seem to consistently target specific tree species. This is positive for the diversity of the Riparian zone as this region is very important both ecologically and aesthetically for the tourists who visit the Park.
- Full Text:
Studies towards the development of novel multidentate ligands
- Authors: Magqi, Nceba
- Date: 2007
- Subjects: Density functionals , Ligands , Ligands -- Design , Ligands -- Analysis , Camphor
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4358 , http://hdl.handle.net/10962/d1005023 , Density functionals , Ligands , Ligands -- Design , Ligands -- Analysis , Camphor
- Description: In this study, attention has been given to the design and synthesis of novel multidentate ligands for use in the construction of ruthenium-based metathesis catalysts, and their chelating potential has been explored by computer modelling at the Density Functional Theory (DFT) level. Both Kemp’s triacid (1,3,5-trimethyl-1,3,5-cyclohexanetricarboxylic acid) and D-(+)-camphor have been investigated as molecular scaffolds for the development of such ligands. However selective elaboration of the functional groups in Kemp’s triacid proved difficult to achieve, and the research has focused on the development of camphor derivatives. The synthesis of the camphor-based ligands has involved C-8 functionalisation and ring-opening of the bicyclic system to afford tridentate products. The formation of 9-iodocamphorquinone bis(ethylene ketal) together with the desired product, the 8-iodo isomer, has been confirmed by single crystal X-ray analysis of both compounds. Formation of the 9-iodo analogue has provided new insights into the intramolecular rearrangement of camphor skeleton, and the mechanistic implications have been assessed by coset analysis. Attempts to effect nucleophilic displacement of the 8-halogeno groups by nucleophilic donor moieties proved unexpectedly difficult and, coupled with the susceptibility of the carbonyl groups to nucleophilic attack, has led to the formation of novel tricyclic products, viz., 1,6-dimethyl-3-(2-pyridylamino)-4-oxatricyclo[4.3.0.0[superscript 3,7]]-2-nonanone and 6,7-dimethyl-3-(2-pyridylamino)-4-oxatricyclo -[4.3.0.0[superscript 3,7]]-2-nonanone. However the diphenylphosphine group was successfully introduced at C-8 and oxidative ring-opening of the camphor skeleton has afforded the tridentate ligands, 2-(diphenylphosphinoylmethyl)-1,2-dimethyl-1,3-cyclopentanedicarboxylic acid and 2-(diphenylphosphinoylmethyl)-1,3-bis(hydroxymethyl)1,2-dimethylcyclopentane. One- and two-dimensional NMR and, where appropriate, high-resolution MS methods have been used to characterise the products. Three [superscript 13]C NMR chemical shift prediction programmes, viz., ChemWindow and the MODGRAPH neural network and HOSE (Hierachially Ordered Spherical description of Environment), have been applied to representative compounds to assess their efficacy. While the predicted shifts correlated reasonably well with the experimental data, they proved to be insufficiently accurate to differentiate the isomeric systems examined.
- Full Text:
- Authors: Magqi, Nceba
- Date: 2007
- Subjects: Density functionals , Ligands , Ligands -- Design , Ligands -- Analysis , Camphor
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4358 , http://hdl.handle.net/10962/d1005023 , Density functionals , Ligands , Ligands -- Design , Ligands -- Analysis , Camphor
- Description: In this study, attention has been given to the design and synthesis of novel multidentate ligands for use in the construction of ruthenium-based metathesis catalysts, and their chelating potential has been explored by computer modelling at the Density Functional Theory (DFT) level. Both Kemp’s triacid (1,3,5-trimethyl-1,3,5-cyclohexanetricarboxylic acid) and D-(+)-camphor have been investigated as molecular scaffolds for the development of such ligands. However selective elaboration of the functional groups in Kemp’s triacid proved difficult to achieve, and the research has focused on the development of camphor derivatives. The synthesis of the camphor-based ligands has involved C-8 functionalisation and ring-opening of the bicyclic system to afford tridentate products. The formation of 9-iodocamphorquinone bis(ethylene ketal) together with the desired product, the 8-iodo isomer, has been confirmed by single crystal X-ray analysis of both compounds. Formation of the 9-iodo analogue has provided new insights into the intramolecular rearrangement of camphor skeleton, and the mechanistic implications have been assessed by coset analysis. Attempts to effect nucleophilic displacement of the 8-halogeno groups by nucleophilic donor moieties proved unexpectedly difficult and, coupled with the susceptibility of the carbonyl groups to nucleophilic attack, has led to the formation of novel tricyclic products, viz., 1,6-dimethyl-3-(2-pyridylamino)-4-oxatricyclo[4.3.0.0[superscript 3,7]]-2-nonanone and 6,7-dimethyl-3-(2-pyridylamino)-4-oxatricyclo -[4.3.0.0[superscript 3,7]]-2-nonanone. However the diphenylphosphine group was successfully introduced at C-8 and oxidative ring-opening of the camphor skeleton has afforded the tridentate ligands, 2-(diphenylphosphinoylmethyl)-1,2-dimethyl-1,3-cyclopentanedicarboxylic acid and 2-(diphenylphosphinoylmethyl)-1,3-bis(hydroxymethyl)1,2-dimethylcyclopentane. One- and two-dimensional NMR and, where appropriate, high-resolution MS methods have been used to characterise the products. Three [superscript 13]C NMR chemical shift prediction programmes, viz., ChemWindow and the MODGRAPH neural network and HOSE (Hierachially Ordered Spherical description of Environment), have been applied to representative compounds to assess their efficacy. While the predicted shifts correlated reasonably well with the experimental data, they proved to be insufficiently accurate to differentiate the isomeric systems examined.
- Full Text:
Study of metallophthalocyanines attached onto pre-modified gold surfaces
- Authors: Mashazi, Philani Nkosinathi
- Date: 2007
- Subjects: Phthalocyanines , Electrochemistry , Electrodes, Enzyme , Glucose -- Measurement
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4361 , http://hdl.handle.net/10962/d1005026 , Phthalocyanines , Electrochemistry , Electrodes, Enzyme , Glucose -- Measurement
- Description: Tetra-carboxy acid chloride phthalocyanine complexes of cobalt, iron and manganese were synthesized and characterized using spectroscopic and electrochemical techniques. These complexes were fabricated as thin films on gold electrode following a covalent immobilization and self-assembling methods. Surface electrochemical and spectroscopic characterization showed that these complexes are surface-confined species. The characterization using spectroscopic and electrochemical methods confirmed the formation of thiol and MPc SAMs on gold electrode. The electrocatalytic behaviour of the SAM modified gold electrodes was studied for the detection of L-cysteine and hydrogen peroxide. The limits of detection (LoD) for Lcysteine were of the orders of 10[superscript -7] mol.L[superscript -1] for all the MPc complexes studied and the LoD for hydrogen peroxide at cobalt phthalocyanine modified gold electrode was of the orders of 10[superscript -7]mol.L[superscript -1] for both electrocatalytic oxidation and reduction. The modification process for gold electrodes was reproducible and showed good stability, if stored in pH 4 phosphate buffer solutions and can be used over a long period of time. The cobalt phthalocyanine modified gold electrode was also investigated for the fabrication of glucose oxidase (GOx)-based biosensor and as an electron mediator between the enzyme and gold electrode. The behaviour of the enzyme modified gold electrode towards the detection of glucose was studied and the results gave a limit of detection of the orders of 10[superscript -6] mol.L[superscript -1] with low binding constant (4.8 mM) of enzyme (GOx) to substrate (glucose) referred to as Michaelis-Menten constant. The practical applications, i.e. the real sample analysis and interference studies, for the enzyme modified gold electrodes were investigated. These studies showed that the enzyme electrode is valuable and can be used for glucose detection.
- Full Text:
- Authors: Mashazi, Philani Nkosinathi
- Date: 2007
- Subjects: Phthalocyanines , Electrochemistry , Electrodes, Enzyme , Glucose -- Measurement
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4361 , http://hdl.handle.net/10962/d1005026 , Phthalocyanines , Electrochemistry , Electrodes, Enzyme , Glucose -- Measurement
- Description: Tetra-carboxy acid chloride phthalocyanine complexes of cobalt, iron and manganese were synthesized and characterized using spectroscopic and electrochemical techniques. These complexes were fabricated as thin films on gold electrode following a covalent immobilization and self-assembling methods. Surface electrochemical and spectroscopic characterization showed that these complexes are surface-confined species. The characterization using spectroscopic and electrochemical methods confirmed the formation of thiol and MPc SAMs on gold electrode. The electrocatalytic behaviour of the SAM modified gold electrodes was studied for the detection of L-cysteine and hydrogen peroxide. The limits of detection (LoD) for Lcysteine were of the orders of 10[superscript -7] mol.L[superscript -1] for all the MPc complexes studied and the LoD for hydrogen peroxide at cobalt phthalocyanine modified gold electrode was of the orders of 10[superscript -7]mol.L[superscript -1] for both electrocatalytic oxidation and reduction. The modification process for gold electrodes was reproducible and showed good stability, if stored in pH 4 phosphate buffer solutions and can be used over a long period of time. The cobalt phthalocyanine modified gold electrode was also investigated for the fabrication of glucose oxidase (GOx)-based biosensor and as an electron mediator between the enzyme and gold electrode. The behaviour of the enzyme modified gold electrode towards the detection of glucose was studied and the results gave a limit of detection of the orders of 10[superscript -6] mol.L[superscript -1] with low binding constant (4.8 mM) of enzyme (GOx) to substrate (glucose) referred to as Michaelis-Menten constant. The practical applications, i.e. the real sample analysis and interference studies, for the enzyme modified gold electrodes were investigated. These studies showed that the enzyme electrode is valuable and can be used for glucose detection.
- Full Text:
Synthesis of novel coumarin derivatives as potential inhibitors of HIV-1 protease
- Authors: Rose, Nathan Rolf
- Date: 2007 , 2013-07-01
- Subjects: Coumarins , Protease Inhibitors , Heterocyclic compounds -- Derivatives , HIV infections -- Treatment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4430 , http://hdl.handle.net/10962/d1007220 , Coumarins , Protease Inhibitors , Heterocyclic compounds -- Derivatives , HIV infections -- Treatment
- Description: This research has focused on the development of novel coumann derivatives containing peptide-like side chains as potential HIV-1 protease inhibitors. The reaction of various salicylaldehyde derivatives with tert-butyl acrylate In the presence of 1,4- diazabicyclo[2.2.2]octane (DABCO) has afforded a series of Baylis-Hillman adducts in moderate yield. Cyclisation of the adducts in the presence of HCI afforded the corresponding 3-(chloromethyl)coumarin derivatives, which have been reacted with various amine hydrochlorides in the presence of Proton Sponge® to afford a series of novel 3- (aminomethyl)coumarin derivatives, which were fully characterised by NMR and HRMS methods. Various approaches to the introduction of hydroxyl or amino groups at the C-4 position of coumarin and the 3-(chloromethyl)coumarin derivatives have been explored; these have included dihydroxylation of the coumarin double bond, and the synthesis of 4- benzylaminocoumarin derivatives as potential intermediates. The Vilsmeier-Haack and Mannich reactions have also been investigated as possible methods of introducing the desired peptide-like functionality. Computer modelling of selected structures has indicated that some of the novel 3- (aminomethyl)coumarin derivatives may exhibit activity as inhibitors of HIV-1 protease. The planned enzyme inhibition assays were unfortunately precluded by the aqueous insolubility of the selected compounds. Three ¹³C NMR chemical shift algorithms, viz., Modgraph Neural Network, Modgraph HOSE and Chern Window, have been applied to selected compounds prepared in this study. The Modgraph Neural Network algorithm was found, in all cases, to provide the most accurate correlations with the experimentally-determined chemical shifts. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Rose, Nathan Rolf
- Date: 2007 , 2013-07-01
- Subjects: Coumarins , Protease Inhibitors , Heterocyclic compounds -- Derivatives , HIV infections -- Treatment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4430 , http://hdl.handle.net/10962/d1007220 , Coumarins , Protease Inhibitors , Heterocyclic compounds -- Derivatives , HIV infections -- Treatment
- Description: This research has focused on the development of novel coumann derivatives containing peptide-like side chains as potential HIV-1 protease inhibitors. The reaction of various salicylaldehyde derivatives with tert-butyl acrylate In the presence of 1,4- diazabicyclo[2.2.2]octane (DABCO) has afforded a series of Baylis-Hillman adducts in moderate yield. Cyclisation of the adducts in the presence of HCI afforded the corresponding 3-(chloromethyl)coumarin derivatives, which have been reacted with various amine hydrochlorides in the presence of Proton Sponge® to afford a series of novel 3- (aminomethyl)coumarin derivatives, which were fully characterised by NMR and HRMS methods. Various approaches to the introduction of hydroxyl or amino groups at the C-4 position of coumarin and the 3-(chloromethyl)coumarin derivatives have been explored; these have included dihydroxylation of the coumarin double bond, and the synthesis of 4- benzylaminocoumarin derivatives as potential intermediates. The Vilsmeier-Haack and Mannich reactions have also been investigated as possible methods of introducing the desired peptide-like functionality. Computer modelling of selected structures has indicated that some of the novel 3- (aminomethyl)coumarin derivatives may exhibit activity as inhibitors of HIV-1 protease. The planned enzyme inhibition assays were unfortunately precluded by the aqueous insolubility of the selected compounds. Three ¹³C NMR chemical shift algorithms, viz., Modgraph Neural Network, Modgraph HOSE and Chern Window, have been applied to selected compounds prepared in this study. The Modgraph Neural Network algorithm was found, in all cases, to provide the most accurate correlations with the experimentally-determined chemical shifts. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
Synthesis of triprenylated toluquinone and toluhydroquinone metabolites from a marine-derived Penicillium fungus
- Authors: Scheepers, Brent Ashley
- Date: 2007
- Subjects: Penicillium , Antineoplastic agents , Marine fungi , Quinone
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4373 , http://hdl.handle.net/10962/d1005038 , Penicillium , Antineoplastic agents , Marine fungi , Quinone
- Description: This project forms part of a collaborative effort between the marine natural products chemists at Rhodes University and the medical biochemists at the University of Cape Town’s School of Medicine. Our UCT collaborators tested the cytotoxicity of a group of toluhydroquinones and toluquinones (9-15) against the oesophageal cancer cell line WHCO1 and revealed that the triprenylated toluhydroquinone 11 and it’s oxidised analogue 12 were the most active. This thesis presents an investigation into the role of the polyprenyl side-chain in the cytotoxicity of compound 11 and it’s oxidised analogue 12 by synthesizing and testing the cytotoxicity of simplified analogues of this compound. The synthesis of the two ortho-prenylated toluhydroquinone analogues 5-methyl-2-[(2'E,6'E)-3',7' -dimethyl-2',6'-octadienyl]-1,4-benzenediol (19) and 5-methyl-2-[(2'E,6'E)-3',7',11'-trimethyl-2',6',10'-dodecatrienyl]-1,4-benzenediol (21) and their two ortho-prenylated toluquinone analogues, 5-methyl-2-[(2'E,6'E)-3',7'-dimethyl-2',6'-octadienyl]-2,5-cyclohexadiene-1,4-dione (20) and 5-methyl-2-[(2'E,6'E)-3',7',11'-trimethyl-2',6',10'-dodecatrienyl]-2,5-cyclohexadiene-1,4-dione (22) is described. Our initial attempts to couple geranyl bromide, farnesyl bromide and farnesal to the aromatic precursors m-cresol and 1,4-dimethoxy-2-methylbenzene using directed ortho-prenylation and phenoxide carbon-alkylation were unsuccessful. The four target analogues were eventually synthesized via the initial metal halogen exchange reaction between 1-bromo-2,5-dimethoxy-4-methylbenzene and geranyl bromide/farnesyl bromide using n-BuLi and TMEDA in ditheyl ether at 0 °C to yield 92 and 104 respectively in moderate yield. The demethylation of both compounds preceded smoothly using AgO giving the target analogues 20 and 22 in good yield (approx. 90 %). The reduction of quinones 20 and 22 with sodium dithionite gave 19 and 21 in quantitative yield. The synthesis reported here is the first regioselective synthesis of these compounds. The anti-oesophageal cancer activity of 19-22 and two commercially available non-prenylated analogues 17 and 18 were tested against WHCO1. The conclusion drawn from the anti-oesophageal cancer study was that the polyprenyl side-chain plays a negligable role in the cytotoxicity of compounds such as 11 and 9 against the oesophageal cancer cell line WHCO1.
- Full Text:
- Authors: Scheepers, Brent Ashley
- Date: 2007
- Subjects: Penicillium , Antineoplastic agents , Marine fungi , Quinone
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4373 , http://hdl.handle.net/10962/d1005038 , Penicillium , Antineoplastic agents , Marine fungi , Quinone
- Description: This project forms part of a collaborative effort between the marine natural products chemists at Rhodes University and the medical biochemists at the University of Cape Town’s School of Medicine. Our UCT collaborators tested the cytotoxicity of a group of toluhydroquinones and toluquinones (9-15) against the oesophageal cancer cell line WHCO1 and revealed that the triprenylated toluhydroquinone 11 and it’s oxidised analogue 12 were the most active. This thesis presents an investigation into the role of the polyprenyl side-chain in the cytotoxicity of compound 11 and it’s oxidised analogue 12 by synthesizing and testing the cytotoxicity of simplified analogues of this compound. The synthesis of the two ortho-prenylated toluhydroquinone analogues 5-methyl-2-[(2'E,6'E)-3',7' -dimethyl-2',6'-octadienyl]-1,4-benzenediol (19) and 5-methyl-2-[(2'E,6'E)-3',7',11'-trimethyl-2',6',10'-dodecatrienyl]-1,4-benzenediol (21) and their two ortho-prenylated toluquinone analogues, 5-methyl-2-[(2'E,6'E)-3',7'-dimethyl-2',6'-octadienyl]-2,5-cyclohexadiene-1,4-dione (20) and 5-methyl-2-[(2'E,6'E)-3',7',11'-trimethyl-2',6',10'-dodecatrienyl]-2,5-cyclohexadiene-1,4-dione (22) is described. Our initial attempts to couple geranyl bromide, farnesyl bromide and farnesal to the aromatic precursors m-cresol and 1,4-dimethoxy-2-methylbenzene using directed ortho-prenylation and phenoxide carbon-alkylation were unsuccessful. The four target analogues were eventually synthesized via the initial metal halogen exchange reaction between 1-bromo-2,5-dimethoxy-4-methylbenzene and geranyl bromide/farnesyl bromide using n-BuLi and TMEDA in ditheyl ether at 0 °C to yield 92 and 104 respectively in moderate yield. The demethylation of both compounds preceded smoothly using AgO giving the target analogues 20 and 22 in good yield (approx. 90 %). The reduction of quinones 20 and 22 with sodium dithionite gave 19 and 21 in quantitative yield. The synthesis reported here is the first regioselective synthesis of these compounds. The anti-oesophageal cancer activity of 19-22 and two commercially available non-prenylated analogues 17 and 18 were tested against WHCO1. The conclusion drawn from the anti-oesophageal cancer study was that the polyprenyl side-chain plays a negligable role in the cytotoxicity of compounds such as 11 and 9 against the oesophageal cancer cell line WHCO1.
- Full Text:
Teacher motivation in a South African school
- Authors: Kovach, John C
- Date: 2007
- Subjects: Teacher morale -- South Africa -- Eastern Cape Teachers -- Professional ethics -- South Africa -- Eastern Cape Teacher-administrator relationships -- South Africa -- Eastern Cape Educational leadership -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1790 , http://hdl.handle.net/10962/d1003675
- Description: This study explores and attempts to shed light on what motivates teachers and how teacher motivation is affected by a principal's leadership style. The worldviews of pragmatism and critical realism were used as the basis for exploring teacher motivation in a South African school. A primary school in the Eastern Cape of South Africa was chosen for the case study. Three data gathering tools, a leadership questionnaire, teacher survey, and interviews were used to generate data on teacher motivation and the interaction between leadership style and teacher motivation. In regards to teachers, religion, social justice, and self-efficacy were all identified as motivators. The principal was strongly charismatic in her leadership and along with transformational and social justice leadership played a major role in influencing teacher behaviors. Self-determination theory was identified as helping to explain different levels of intrinsic and extrinsic motivation and thereby to better understand varying degrees of teacher motivation. There are many difficulties in South African education and around the world in general and this study is premised on the belief that if teacher motivation can be studied and advanced there will be an improvement in education and learning. This thesis was limited in its scope and ability to fully explore the different levels of ontology as outlined by the critical realist and this is identified as a possible future course of action for not only studying teacher motivation but getting to the 'heart of the matter'.
- Full Text:
- Authors: Kovach, John C
- Date: 2007
- Subjects: Teacher morale -- South Africa -- Eastern Cape Teachers -- Professional ethics -- South Africa -- Eastern Cape Teacher-administrator relationships -- South Africa -- Eastern Cape Educational leadership -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1790 , http://hdl.handle.net/10962/d1003675
- Description: This study explores and attempts to shed light on what motivates teachers and how teacher motivation is affected by a principal's leadership style. The worldviews of pragmatism and critical realism were used as the basis for exploring teacher motivation in a South African school. A primary school in the Eastern Cape of South Africa was chosen for the case study. Three data gathering tools, a leadership questionnaire, teacher survey, and interviews were used to generate data on teacher motivation and the interaction between leadership style and teacher motivation. In regards to teachers, religion, social justice, and self-efficacy were all identified as motivators. The principal was strongly charismatic in her leadership and along with transformational and social justice leadership played a major role in influencing teacher behaviors. Self-determination theory was identified as helping to explain different levels of intrinsic and extrinsic motivation and thereby to better understand varying degrees of teacher motivation. There are many difficulties in South African education and around the world in general and this study is premised on the belief that if teacher motivation can be studied and advanced there will be an improvement in education and learning. This thesis was limited in its scope and ability to fully explore the different levels of ontology as outlined by the critical realist and this is identified as a possible future course of action for not only studying teacher motivation but getting to the 'heart of the matter'.
- Full Text:
The artistic path to virtue
- Authors: Sher, Gavin
- Date: 2007
- Subjects: Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2732 , http://hdl.handle.net/10962/d1004370 , Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Description: Most people share a strong intuition that there is much to be learned from great literature and other forms of narrative art. This intuition is, however, philosophically contentious. Plato was the first to argue against the possibility of learning anything from narrative art, but he founded a tradition that persists to the present day. I will engage in this debate in order to examine the role narratives might be able to play in acquiring virtue on Aristotle's ethical account, as it is presented in Nicomachean Ethics. I will claim that narratives have so long seemed a problematic source of learning because philosophers have traditionally approached the issue in the wrong way. They have typically tried to show how we might acquire propositional knowledge through our engagement with art, but this approach has failed because of insoluble problems involved in satisfying the justification criterion. Fictions may be rescued from their problematic status by realising that what we truly get from them is, instead, a type of knowledge-how. I will argue that Aristotelian virtue is itself a kind of knowledge-how and so the type of learning that takes place in engaging with narratives has a role to play in its acquisition and exercise. Virtue depends on types of reasoning that are themselves kinds of knowledge-how and which are employed and improved in engaging with narrative art. These types of reasoning will be described as conceptual, emotional and imaginative understanding. I will show how each is important in relation to virtue and how each is a kind of knowledge-how that may be improved through exposure to narrative art.
- Full Text:
- Authors: Sher, Gavin
- Date: 2007
- Subjects: Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2732 , http://hdl.handle.net/10962/d1004370 , Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Description: Most people share a strong intuition that there is much to be learned from great literature and other forms of narrative art. This intuition is, however, philosophically contentious. Plato was the first to argue against the possibility of learning anything from narrative art, but he founded a tradition that persists to the present day. I will engage in this debate in order to examine the role narratives might be able to play in acquiring virtue on Aristotle's ethical account, as it is presented in Nicomachean Ethics. I will claim that narratives have so long seemed a problematic source of learning because philosophers have traditionally approached the issue in the wrong way. They have typically tried to show how we might acquire propositional knowledge through our engagement with art, but this approach has failed because of insoluble problems involved in satisfying the justification criterion. Fictions may be rescued from their problematic status by realising that what we truly get from them is, instead, a type of knowledge-how. I will argue that Aristotelian virtue is itself a kind of knowledge-how and so the type of learning that takes place in engaging with narratives has a role to play in its acquisition and exercise. Virtue depends on types of reasoning that are themselves kinds of knowledge-how and which are employed and improved in engaging with narrative art. These types of reasoning will be described as conceptual, emotional and imaginative understanding. I will show how each is important in relation to virtue and how each is a kind of knowledge-how that may be improved through exposure to narrative art.
- Full Text:
The continued viability of the discretionary Inter vivos trust as an instrument for estate planning
- Lötter, Therésilda Sieglinde
- Authors: Lötter, Therésilda Sieglinde
- Date: 2007
- Subjects: Taxation -- Law and legislation -- South Africa , Trusts and trustees -- South Africa , Trusts and trustees -- Taxation -- South Africa , Estate planning -- South Africa , Estates (Law) -- South Africa
- Language: Afrikaans
- Type: Thesis , Masters , MCom
- Identifier: vital:900 , http://hdl.handle.net/10962/d1006148 , Taxation -- Law and legislation -- South Africa , Trusts and trustees -- South Africa , Trusts and trustees -- Taxation -- South Africa , Estate planning -- South Africa , Estates (Law) -- South Africa
- Description: The purpose of this study is to determine whether a discretionary inter vivos trust is still an effective instrument for estate planning. The process of estate planning, the role the trust plays in it and the background to the trust are described. The taxability and tax saving opportunities when the trust are utilised are discussed in the light of the Estate Duty Act, 45 of 1955, the Income Tax Act, 58 of 1962 (including the Eighth Schedule thereof) and the Transfer Duty Act, 40 of 1949. The opinions of tax and legal authorities in articles and relevant case law are also discussed. The impact of the "letter of wishes" on the stipulations of the trust deed is examined. Amendments to the Income Tax Act have placed a limit on the use of a trust for estate planning through a number of anti-avoidance measures, the introduction of a capital gains tax (in the Eighth Schedule) and the imposition of a high tax rate. The increase in the deduction granted in arriving at the dutiable amount of an estate, in terms of section 4A of the Estate Duty Act, from R1 500 000 to R2 500 000 has imposed a further limit on the use of the trust as an instrument in estate planning. The research demonstrates that, notwithstanding the amendments to the Income Tax Act, the trust still is a viable instrument, mainly because the trust operates as a conduit and because of its potential use in dividing taxable income amongst a number of beneficiaries. The stipulations included in the trust deed and the "letter of wishes" (if one exists), must be thought through carefully when estate planning is done, as it can give rise to the application of the general and specific anti-avoidance provisions as included in sections 7 and 103 of this Act. The research also concludes that, in assessing the effectiveness of the trust as an instrument in tax planning, the disadvantage of paying the higher transfer duty when the immovable asset is transferred to the trust should be weighed up against the possible saving in income tax and estate duty at a later stage. It is also clear that most assets owned by the trust are tax neutral, whilst many of the amendments under discussion deal with the taxability of trust income. The quantitative considerations underlying the use of the trust as part of the estate plan, remain unchanged. The research concludes by providing a framework of quantitative and qualitative criteria that can be used by an estate planner to determine whether it will be advantageous to transfer an asset to the trust to achieve the objectives of the estate plan.
- Full Text:
- Authors: Lötter, Therésilda Sieglinde
- Date: 2007
- Subjects: Taxation -- Law and legislation -- South Africa , Trusts and trustees -- South Africa , Trusts and trustees -- Taxation -- South Africa , Estate planning -- South Africa , Estates (Law) -- South Africa
- Language: Afrikaans
- Type: Thesis , Masters , MCom
- Identifier: vital:900 , http://hdl.handle.net/10962/d1006148 , Taxation -- Law and legislation -- South Africa , Trusts and trustees -- South Africa , Trusts and trustees -- Taxation -- South Africa , Estate planning -- South Africa , Estates (Law) -- South Africa
- Description: The purpose of this study is to determine whether a discretionary inter vivos trust is still an effective instrument for estate planning. The process of estate planning, the role the trust plays in it and the background to the trust are described. The taxability and tax saving opportunities when the trust are utilised are discussed in the light of the Estate Duty Act, 45 of 1955, the Income Tax Act, 58 of 1962 (including the Eighth Schedule thereof) and the Transfer Duty Act, 40 of 1949. The opinions of tax and legal authorities in articles and relevant case law are also discussed. The impact of the "letter of wishes" on the stipulations of the trust deed is examined. Amendments to the Income Tax Act have placed a limit on the use of a trust for estate planning through a number of anti-avoidance measures, the introduction of a capital gains tax (in the Eighth Schedule) and the imposition of a high tax rate. The increase in the deduction granted in arriving at the dutiable amount of an estate, in terms of section 4A of the Estate Duty Act, from R1 500 000 to R2 500 000 has imposed a further limit on the use of the trust as an instrument in estate planning. The research demonstrates that, notwithstanding the amendments to the Income Tax Act, the trust still is a viable instrument, mainly because the trust operates as a conduit and because of its potential use in dividing taxable income amongst a number of beneficiaries. The stipulations included in the trust deed and the "letter of wishes" (if one exists), must be thought through carefully when estate planning is done, as it can give rise to the application of the general and specific anti-avoidance provisions as included in sections 7 and 103 of this Act. The research also concludes that, in assessing the effectiveness of the trust as an instrument in tax planning, the disadvantage of paying the higher transfer duty when the immovable asset is transferred to the trust should be weighed up against the possible saving in income tax and estate duty at a later stage. It is also clear that most assets owned by the trust are tax neutral, whilst many of the amendments under discussion deal with the taxability of trust income. The quantitative considerations underlying the use of the trust as part of the estate plan, remain unchanged. The research concludes by providing a framework of quantitative and qualitative criteria that can be used by an estate planner to determine whether it will be advantageous to transfer an asset to the trust to achieve the objectives of the estate plan.
- Full Text:
The cost of credit in the micro-finance industry in South Africa
- Authors: Campbell, Jonathan
- Date: 2007
- Subjects: Contracts -- South Africa , Credit -- Law and legislation -- South Africa , Microfinance -- South Africa , Usury laws -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3667 , http://hdl.handle.net/10962/d1003182 , Contracts -- South Africa , Credit -- Law and legislation -- South Africa , Microfinance -- South Africa , Usury laws -- South Africa
- Description: This thesis analyses the cost of credit in the micro-finance industry in South Africa. The study situates micro-lending agreements within the law of contract, beginning with an examination of contractual fairness in terms of the common law: the fundamental principle of freedom of contract that underpins the common law of contract; the principle that agreements contrary to public policy should not be enforced; and the impetus given by constitutional values that inform public policy. In regard to moneylending transactions, common law usury law will be explained. The study then goes on to trace the origins and rapid growth of the micro-finance industry which was made possible by its exemption in 1992 from the Usury Act 73 of 1968. The upshot of this development was that registered micro-lenders have for nearly 14 years charged excessive interest rates, and continue to do so. The dire socio-economic impact of these high interest rates on individual consumers and lowincome communities is then demonstrated: how borrowers of small loans soon become over-indebted; the loss of billions of rands every year to low-income communities in the form of interest on micro-loans. The study then shifts to the legislative response to the need for consumer protection in regard to consumer credit. The extensive credit law review process is explained, resulting ultimately in the National Credit Act 34 of 2005, which allows the Minister to prescribe limits on interest rates and fees in all sectors of the consumer credit market. The prescribed limits on the cost of credit in the micro-finance sector are thoroughly explained and analysed, with particular reference to the implications of each element of the credit costing structure, and the combined impact of the total cost of credit on different types and sizes of loans. The envisaged maximum interest and fees will markedly alter the positions of micro-lenders and consumers, and receive careful analysis. The study closes with a summary of findings in the thesis, which includes suggested amendments to the National Credit Regulations and a review of possible legal challenges to the high cost of credit on smaller loans.
- Full Text:
- Authors: Campbell, Jonathan
- Date: 2007
- Subjects: Contracts -- South Africa , Credit -- Law and legislation -- South Africa , Microfinance -- South Africa , Usury laws -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3667 , http://hdl.handle.net/10962/d1003182 , Contracts -- South Africa , Credit -- Law and legislation -- South Africa , Microfinance -- South Africa , Usury laws -- South Africa
- Description: This thesis analyses the cost of credit in the micro-finance industry in South Africa. The study situates micro-lending agreements within the law of contract, beginning with an examination of contractual fairness in terms of the common law: the fundamental principle of freedom of contract that underpins the common law of contract; the principle that agreements contrary to public policy should not be enforced; and the impetus given by constitutional values that inform public policy. In regard to moneylending transactions, common law usury law will be explained. The study then goes on to trace the origins and rapid growth of the micro-finance industry which was made possible by its exemption in 1992 from the Usury Act 73 of 1968. The upshot of this development was that registered micro-lenders have for nearly 14 years charged excessive interest rates, and continue to do so. The dire socio-economic impact of these high interest rates on individual consumers and lowincome communities is then demonstrated: how borrowers of small loans soon become over-indebted; the loss of billions of rands every year to low-income communities in the form of interest on micro-loans. The study then shifts to the legislative response to the need for consumer protection in regard to consumer credit. The extensive credit law review process is explained, resulting ultimately in the National Credit Act 34 of 2005, which allows the Minister to prescribe limits on interest rates and fees in all sectors of the consumer credit market. The prescribed limits on the cost of credit in the micro-finance sector are thoroughly explained and analysed, with particular reference to the implications of each element of the credit costing structure, and the combined impact of the total cost of credit on different types and sizes of loans. The envisaged maximum interest and fees will markedly alter the positions of micro-lenders and consumers, and receive careful analysis. The study closes with a summary of findings in the thesis, which includes suggested amendments to the National Credit Regulations and a review of possible legal challenges to the high cost of credit on smaller loans.
- Full Text:
The demand for broad money (M2) in Botswana
- Authors: Tsheole, Thapelo
- Date: 2007
- Subjects: Monetary policy -- Botswana , Demand for money -- Botswana , Botswana -- Economic conditions , Quantity theory of money
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:966 , http://hdl.handle.net/10962/d1002700 , Monetary policy -- Botswana , Demand for money -- Botswana , Botswana -- Economic conditions , Quantity theory of money
- Description: There has been extensive theoretical and empirical research on the subject of demand for money function. This particularly stems from the important role demand for money plays in macroeconomic analysis, especially in the design and implementation of monetary policy. The increase in studies, especially in developing countries, can also be attributed to a number of factors like: the impact of moving towards flexible exchange rate regimes, globalisation of financial markets, ongoing financial liberalisation, innovations in domestic financial products, the advancement in econometrics techniques and other country-specific events. This study estimates and examines the nature and stability of the demand for broad money (M2) in Botswana. This is particularly important in that the usefulness of a money demand function in the conduct of monetary policy depends crucially on its stability. The stability of the money demand function is crucial in that a stable money demand function would mean that the quantity of money is predictably related to a set of key economic variables linking money and the real economic sector. Therefore, this will help central banks to select appropriate monetary policy actions. Based on the findings, the study also proposes policy interventions. The vast majority of the literature on demand for money has underscored the fact that variable selection and representation, and the framework chosen are the two major issues relevant to modelling and estimation of the demand for money function. In modelling and estimating the demand for money function in Botswana, this study surveys a stream of theoretical and empirical literature on money demand in developed and developing countries, including countries that have similar financial sector similar to Botswana. Due consideration is also given to the macroeconomic and financial sector development in Botswana to help in the identification of the variables that are included in the demand for money equation. Most importantly, this helped in getting meaningful results that are free from theoretical and estimation problems. In particular, this study applied the multivariate cointegration approach as proposed by Johansen (1988) and Johansen and Juselius (1990) to estimate the relationship between broad money (M2), real income, interest rate, South African treasury bill rate, inflation rate and US dollar/pula bilateral exchange rate. The study obtains one unique long run relationship between money and the scale and opportunity cost variables. The coefficients of the long run relationship are then modelled along the general to specific approach as proposed by Campos, Ericsson and Hendry (2005). In this type of approach the general model is reduced by sequential elimination of statistically insignificant variables and checking the validity of the reductions at every stage to ensure congruence of the finally selected parsimonious model. In accordance with the economic quantity theory of money, the long run income elasticity obtained is 0.8021, which is close to the value one (unitary) suggested by economic theory. The coefficients of real income, exchange and inflation rate have the expected positive signs and were significant in the long run. Therefore, the long run demand for money (M2) in Botswana was found to be positively affected by real income, inflation rate and exchange rate. The lack of statistical significant of the own rate of money (88 day commercial bank deposit rate) and the foreign opportunity cost variable (South African Treasury bill rate) is attributed to multi-collinearity problems between these two interest rates. This could be caused by the fact that short term rates in Botswana are very responsive to movements in the money markets rates in South Africa. The short run dynamics of the demand for money function shows the slow speed of adjustment to equilibrium of about 2.9 percent in the first quarter and this is reflective of the lack of sufficient availability of banking services and the low returns on financial assets which could allow economic agents to re-establish equilibrium levels of money holdings faster. The final parsimonious model obtained clearly reflects a well specified stable demand for money function. Therefore, based on the findings we can be precise in stating that targeting a monetary aggregate can be a viable policy for the monetary authorities in Botswana.
- Full Text:
- Authors: Tsheole, Thapelo
- Date: 2007
- Subjects: Monetary policy -- Botswana , Demand for money -- Botswana , Botswana -- Economic conditions , Quantity theory of money
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:966 , http://hdl.handle.net/10962/d1002700 , Monetary policy -- Botswana , Demand for money -- Botswana , Botswana -- Economic conditions , Quantity theory of money
- Description: There has been extensive theoretical and empirical research on the subject of demand for money function. This particularly stems from the important role demand for money plays in macroeconomic analysis, especially in the design and implementation of monetary policy. The increase in studies, especially in developing countries, can also be attributed to a number of factors like: the impact of moving towards flexible exchange rate regimes, globalisation of financial markets, ongoing financial liberalisation, innovations in domestic financial products, the advancement in econometrics techniques and other country-specific events. This study estimates and examines the nature and stability of the demand for broad money (M2) in Botswana. This is particularly important in that the usefulness of a money demand function in the conduct of monetary policy depends crucially on its stability. The stability of the money demand function is crucial in that a stable money demand function would mean that the quantity of money is predictably related to a set of key economic variables linking money and the real economic sector. Therefore, this will help central banks to select appropriate monetary policy actions. Based on the findings, the study also proposes policy interventions. The vast majority of the literature on demand for money has underscored the fact that variable selection and representation, and the framework chosen are the two major issues relevant to modelling and estimation of the demand for money function. In modelling and estimating the demand for money function in Botswana, this study surveys a stream of theoretical and empirical literature on money demand in developed and developing countries, including countries that have similar financial sector similar to Botswana. Due consideration is also given to the macroeconomic and financial sector development in Botswana to help in the identification of the variables that are included in the demand for money equation. Most importantly, this helped in getting meaningful results that are free from theoretical and estimation problems. In particular, this study applied the multivariate cointegration approach as proposed by Johansen (1988) and Johansen and Juselius (1990) to estimate the relationship between broad money (M2), real income, interest rate, South African treasury bill rate, inflation rate and US dollar/pula bilateral exchange rate. The study obtains one unique long run relationship between money and the scale and opportunity cost variables. The coefficients of the long run relationship are then modelled along the general to specific approach as proposed by Campos, Ericsson and Hendry (2005). In this type of approach the general model is reduced by sequential elimination of statistically insignificant variables and checking the validity of the reductions at every stage to ensure congruence of the finally selected parsimonious model. In accordance with the economic quantity theory of money, the long run income elasticity obtained is 0.8021, which is close to the value one (unitary) suggested by economic theory. The coefficients of real income, exchange and inflation rate have the expected positive signs and were significant in the long run. Therefore, the long run demand for money (M2) in Botswana was found to be positively affected by real income, inflation rate and exchange rate. The lack of statistical significant of the own rate of money (88 day commercial bank deposit rate) and the foreign opportunity cost variable (South African Treasury bill rate) is attributed to multi-collinearity problems between these two interest rates. This could be caused by the fact that short term rates in Botswana are very responsive to movements in the money markets rates in South Africa. The short run dynamics of the demand for money function shows the slow speed of adjustment to equilibrium of about 2.9 percent in the first quarter and this is reflective of the lack of sufficient availability of banking services and the low returns on financial assets which could allow economic agents to re-establish equilibrium levels of money holdings faster. The final parsimonious model obtained clearly reflects a well specified stable demand for money function. Therefore, based on the findings we can be precise in stating that targeting a monetary aggregate can be a viable policy for the monetary authorities in Botswana.
- Full Text:
The design and assessment of an integrated municipal waste beneficiation facility : towards improved sewage sludge management in developing countries
- Authors: Keirungi, Juliana
- Date: 2007
- Subjects: Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4755 , http://hdl.handle.net/10962/d1007138 , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Description: This research aimed to firstly confirm the hypothesis that the current management of sewage sludge generated during the treatment of wastewater in the Eastern Cape Province of South Africa is poor and, as such, this material poses a threat to local environmental and human health. Secondly, through a rational design approach, the current research also aimed to design and assess the suitability of a novel integrated process incorporating appropriate technologies for improved sewage sludge management. The lack of an appropriate tool for the assessment of the integrated process necessitated the development of an appropriate technology assessment (TA) methodology based on environmental, technical, social and economic criteria. A combination of informal participatory methods such as semi-structured interviews and formal research methods including questionnaires, risk assessment exercises and laboratory analyses were used. Based on the above it was estimated that 116 tons dry sludge were generated in the province per day and that the concentration of heavy metals present in the sludge was generally within the limits for reuse on agricultural land. Furthermore the sludge from all sample sewage treatment works (STWs) was found to be free of any detectable pathogens. Despite the above, a preliminary risk assessment and chemical analysis revealed that existing sludge management practices at sample STWs posed a threat to the environment, particularly to water resources and exacerbated the problems associated with the discharge of poorly treated municipal wastewater. The root causes of the poor sludge management were considered to be a lack of non-regulatory incentives and financial resources. Highly integrated ecologically engineered systems were thought to offer a solution to the dual problem of poor sludge management and municipal effluent treatment, while providing necessary economic incentives. To facilitate the design of a system appropriate to local conditions, it was necessary to first develop a rational design methodology, which incorporated a detailed TA step. The result of the design process was an Integrated Waste Beneficiation Facility (IWBF) that incorporated a number of process units comprised of appropriate technologies including composting, vermicomposting, algal ponding technology and aquaculture. A detailed TA indicated that the benefits of the proposed IWBF would, at the majority of sample sites, outweigh the potential negative impacts and it was thus recommended that investigations should continue on pilot-scale facilities. Furthermore, although the proposed TA based on four sustainability criteria categories was thought to provide a more accurate assessment of the true sustainability of a technology, the acquisition of information was problematic highlighting the need to re-think current TA methodologies and to address associated constraints allowing the tool to be used and fully comprehensive.
- Full Text:
- Authors: Keirungi, Juliana
- Date: 2007
- Subjects: Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4755 , http://hdl.handle.net/10962/d1007138 , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Description: This research aimed to firstly confirm the hypothesis that the current management of sewage sludge generated during the treatment of wastewater in the Eastern Cape Province of South Africa is poor and, as such, this material poses a threat to local environmental and human health. Secondly, through a rational design approach, the current research also aimed to design and assess the suitability of a novel integrated process incorporating appropriate technologies for improved sewage sludge management. The lack of an appropriate tool for the assessment of the integrated process necessitated the development of an appropriate technology assessment (TA) methodology based on environmental, technical, social and economic criteria. A combination of informal participatory methods such as semi-structured interviews and formal research methods including questionnaires, risk assessment exercises and laboratory analyses were used. Based on the above it was estimated that 116 tons dry sludge were generated in the province per day and that the concentration of heavy metals present in the sludge was generally within the limits for reuse on agricultural land. Furthermore the sludge from all sample sewage treatment works (STWs) was found to be free of any detectable pathogens. Despite the above, a preliminary risk assessment and chemical analysis revealed that existing sludge management practices at sample STWs posed a threat to the environment, particularly to water resources and exacerbated the problems associated with the discharge of poorly treated municipal wastewater. The root causes of the poor sludge management were considered to be a lack of non-regulatory incentives and financial resources. Highly integrated ecologically engineered systems were thought to offer a solution to the dual problem of poor sludge management and municipal effluent treatment, while providing necessary economic incentives. To facilitate the design of a system appropriate to local conditions, it was necessary to first develop a rational design methodology, which incorporated a detailed TA step. The result of the design process was an Integrated Waste Beneficiation Facility (IWBF) that incorporated a number of process units comprised of appropriate technologies including composting, vermicomposting, algal ponding technology and aquaculture. A detailed TA indicated that the benefits of the proposed IWBF would, at the majority of sample sites, outweigh the potential negative impacts and it was thus recommended that investigations should continue on pilot-scale facilities. Furthermore, although the proposed TA based on four sustainability criteria categories was thought to provide a more accurate assessment of the true sustainability of a technology, the acquisition of information was problematic highlighting the need to re-think current TA methodologies and to address associated constraints allowing the tool to be used and fully comprehensive.
- Full Text:
The educationally-related challenges faced by teenage mothers on returning to school: a Namibian case study
- Authors: Shaningwa, Lilia Mariro
- Date: 2007
- Subjects: Teenage mothers -- Namibia -- Case studies Teenagers -- Education -- Namibia -- Case studies Education, Secondary -- Namibia -- Case studies Teenage pregnancy -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1506 , http://hdl.handle.net/10962/d1003388
- Description: The study aimed to investigate the educationally-related challenges faced by teenage mothers in coming back to school in two senior schools in the Kavango Education Region. This small-scale study focused on the challenges that influence or affect the academic progress and development of these learners. The study looked at how teenage pregnancy is perceived as a social problem in many countries as well as in Namibia and examined its impact on the educational aspirations of the young mothers. Namibia has a policy in place to cater for the continued education of learners returning to school after the birth of their babies. This policy was analysed and its implementation in the selected schools formed part of the study, The findings revealed that the educational challenges faced by these young women range from social exclusion to the need to manage the dual responsibilities of motherhood and study. The way in which the learners who participated in this study are viewed by their peers and their teachers was found to be influenced by the cultural connotations ascribed to women as soon as they become mothers, a factor that adds to the challenges these learners face when returning to schools. Cultural connotations which perceived a mother as an adult in the society was attached to the change of the behaviours and attitudes of school young mothers. The findings also showed that while these learners tended to be withdrawn in class and were generally unable to participate in extra-mural activities, they none the less were able to compete with their peers in terms of their academic performance. The study revealed that there is no shared understanding of the policy among the participants and that it is not effectively implemented in the schools, nor is it uniformly applied.
- Full Text:
- Authors: Shaningwa, Lilia Mariro
- Date: 2007
- Subjects: Teenage mothers -- Namibia -- Case studies Teenagers -- Education -- Namibia -- Case studies Education, Secondary -- Namibia -- Case studies Teenage pregnancy -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1506 , http://hdl.handle.net/10962/d1003388
- Description: The study aimed to investigate the educationally-related challenges faced by teenage mothers in coming back to school in two senior schools in the Kavango Education Region. This small-scale study focused on the challenges that influence or affect the academic progress and development of these learners. The study looked at how teenage pregnancy is perceived as a social problem in many countries as well as in Namibia and examined its impact on the educational aspirations of the young mothers. Namibia has a policy in place to cater for the continued education of learners returning to school after the birth of their babies. This policy was analysed and its implementation in the selected schools formed part of the study, The findings revealed that the educational challenges faced by these young women range from social exclusion to the need to manage the dual responsibilities of motherhood and study. The way in which the learners who participated in this study are viewed by their peers and their teachers was found to be influenced by the cultural connotations ascribed to women as soon as they become mothers, a factor that adds to the challenges these learners face when returning to schools. Cultural connotations which perceived a mother as an adult in the society was attached to the change of the behaviours and attitudes of school young mothers. The findings also showed that while these learners tended to be withdrawn in class and were generally unable to participate in extra-mural activities, they none the less were able to compete with their peers in terms of their academic performance. The study revealed that there is no shared understanding of the policy among the participants and that it is not effectively implemented in the schools, nor is it uniformly applied.
- Full Text:
The effect of elephants (Loxodonta africana, Blumenbach, 1797) on Xeric Succulent Thicket
- Authors: Knott, Edward Joseph
- Date: 2007
- Subjects: Addo Elephant National Park (South Africa) , African elephant , Elephants -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Woody plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5674 , http://hdl.handle.net/10962/d1005359 , Addo Elephant National Park (South Africa) , African elephant , Elephants -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Woody plants -- South Africa -- Eastern Cape
- Description: This study looks at the impact of elephant feeding on the Xeric Succulent Thicket component of Eastern Cape Subtropical Thicket (ECST) in Addo Elephant National Park (AENP). Observations of elephant feeding were carried out and vegetation transects were surveyed for impact of elephant feeding. The results indicated that the Nyati elephants spent the majority of their time grazing (nearly 90%), particularly the cow-young herds, and especially when the herd gathered in larger numbers. Browsing events were concentrated on Acacia karroo (81%) and there was no significant difference between the sexes in their preference for this species. Despite being subjected to most of the browsing, the majority of A. karroo trees were undamaged and the effect of elephants was generally light. It appears unlikely that, three years after re-introduction to Nyati, the elephants have had an effect on community structure of the vegetation. Surveys were conducted on stands of the alien invasive weed prickly pear Opuntia ficus-indica, and it was recorded that elephants in Nyati have had a dramatic effect on prickly pear, utilising all adult plants assessed and destroying 70% of them. This level of destruction in such a short period of time suggests that prickly pear is a highly favoured species. The results from the present study suggest that elephants can play a role in the control of prickly pear. Results are discussed in terms of elephants as both megaherbivores and keystone species, and as agents of intermediate disturbance.
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- Authors: Knott, Edward Joseph
- Date: 2007
- Subjects: Addo Elephant National Park (South Africa) , African elephant , Elephants -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Woody plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5674 , http://hdl.handle.net/10962/d1005359 , Addo Elephant National Park (South Africa) , African elephant , Elephants -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Woody plants -- South Africa -- Eastern Cape
- Description: This study looks at the impact of elephant feeding on the Xeric Succulent Thicket component of Eastern Cape Subtropical Thicket (ECST) in Addo Elephant National Park (AENP). Observations of elephant feeding were carried out and vegetation transects were surveyed for impact of elephant feeding. The results indicated that the Nyati elephants spent the majority of their time grazing (nearly 90%), particularly the cow-young herds, and especially when the herd gathered in larger numbers. Browsing events were concentrated on Acacia karroo (81%) and there was no significant difference between the sexes in their preference for this species. Despite being subjected to most of the browsing, the majority of A. karroo trees were undamaged and the effect of elephants was generally light. It appears unlikely that, three years after re-introduction to Nyati, the elephants have had an effect on community structure of the vegetation. Surveys were conducted on stands of the alien invasive weed prickly pear Opuntia ficus-indica, and it was recorded that elephants in Nyati have had a dramatic effect on prickly pear, utilising all adult plants assessed and destroying 70% of them. This level of destruction in such a short period of time suggests that prickly pear is a highly favoured species. The results from the present study suggest that elephants can play a role in the control of prickly pear. Results are discussed in terms of elephants as both megaherbivores and keystone species, and as agents of intermediate disturbance.
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The effect of geography, cultivation and harvest technique on the umckalin concentration and growth of pelargonium sidoides (Geraniaceae)
- Authors: White, Andrew Graeme
- Date: 2007
- Subjects: Pelargoniums , Geraniaceae , Botany -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Medicinal plants -- South Africa -- Eastern Cape , Coumarins
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4234 , http://hdl.handle.net/10962/d1003803 , Pelargoniums , Geraniaceae , Botany -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Medicinal plants -- South Africa -- Eastern Cape , Coumarins
- Description: Pelargonium sidoides DC. (Geraniaceae) root extracts are used in the Eastern Cape Province of South Africa as a traditional medicine for the treatment of respiratory tract and gastro-intestinal infections. Ethanolic extracts are used globally as herbal treatments for bronchitis, asthma and as an immune system booster. Despite documented exploitation of wild populations by illegal harvesters, this species has not been awarded a protected status. The high level of harvest in the years preceding this study prompted this investigation of the prospects for sustainable root harvest through wild harvest and greenhouse cultivation. A novel method was developed for the purification of umckalin, a bioactive constituent in root extracts, such that the root umckalin concentrations of wild and cultivated plants could be quantified by HPLC. As part of the cultivation experiments, the concentration of umckalin in roots was measured for plants across part of the species’ distribution range in the Eastern Cape Province. This survey revealed that root umckalin concentrations were inversely related to the average annual rainfall of the collection site (r² = 0.94, p = 0.007) and directly related to soil pH (r² = 0.97, p = 0.002). Thus, the possibility of inducing high umckalin concentrations in greenhouse-cultivated plants was investigated by subjecting plants to rapid and prolonged water stress treatments. Two leaf applied hormone treatments (cytokinin and gibberellin) and a root competition treatment with a fast growing annual (Conyza albida) were also investigated based on the potential function of umckalin in P. sidoides plants. These five treatments did not significantly affect root umckalin concentrations compared to well-watered controls. The results of further experiments suggested that umckalin production may have been influenced by the geographical origin and genetics of plants rather than environmental variation. Following wild harvest experiments, the regrowth of replanted shoots from which a standard proportion of the root was harvested showed that water availability affected shoot survival but not root regrowth rate. Regrowth rates were low, questioning the viability of wild harvest. In contrast, greenhouse cultivated plants showed ca. six times greater growth rates, supporting the cultivation of roots to supply future market demand.
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- Authors: White, Andrew Graeme
- Date: 2007
- Subjects: Pelargoniums , Geraniaceae , Botany -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Medicinal plants -- South Africa -- Eastern Cape , Coumarins
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4234 , http://hdl.handle.net/10962/d1003803 , Pelargoniums , Geraniaceae , Botany -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Medicinal plants -- South Africa -- Eastern Cape , Coumarins
- Description: Pelargonium sidoides DC. (Geraniaceae) root extracts are used in the Eastern Cape Province of South Africa as a traditional medicine for the treatment of respiratory tract and gastro-intestinal infections. Ethanolic extracts are used globally as herbal treatments for bronchitis, asthma and as an immune system booster. Despite documented exploitation of wild populations by illegal harvesters, this species has not been awarded a protected status. The high level of harvest in the years preceding this study prompted this investigation of the prospects for sustainable root harvest through wild harvest and greenhouse cultivation. A novel method was developed for the purification of umckalin, a bioactive constituent in root extracts, such that the root umckalin concentrations of wild and cultivated plants could be quantified by HPLC. As part of the cultivation experiments, the concentration of umckalin in roots was measured for plants across part of the species’ distribution range in the Eastern Cape Province. This survey revealed that root umckalin concentrations were inversely related to the average annual rainfall of the collection site (r² = 0.94, p = 0.007) and directly related to soil pH (r² = 0.97, p = 0.002). Thus, the possibility of inducing high umckalin concentrations in greenhouse-cultivated plants was investigated by subjecting plants to rapid and prolonged water stress treatments. Two leaf applied hormone treatments (cytokinin and gibberellin) and a root competition treatment with a fast growing annual (Conyza albida) were also investigated based on the potential function of umckalin in P. sidoides plants. These five treatments did not significantly affect root umckalin concentrations compared to well-watered controls. The results of further experiments suggested that umckalin production may have been influenced by the geographical origin and genetics of plants rather than environmental variation. Following wild harvest experiments, the regrowth of replanted shoots from which a standard proportion of the root was harvested showed that water availability affected shoot survival but not root regrowth rate. Regrowth rates were low, questioning the viability of wild harvest. In contrast, greenhouse cultivated plants showed ca. six times greater growth rates, supporting the cultivation of roots to supply future market demand.
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The effects of selected reference toxicants on embryonic development of the freshwater shrimp caridina nilotica (Decapoda: Atyidae)
- Authors: Ketse, Noziphiwo
- Date: 2007
- Subjects: Toxicity testing -- South Africa , Shrimp fisheries -- South Africa , Decapoda , Caridina , Water quality management -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:6025 , http://hdl.handle.net/10962/d1005367 , Toxicity testing -- South Africa , Shrimp fisheries -- South Africa , Decapoda , Caridina , Water quality management -- South Africa
- Description: Aquatic toxicity tests are increasingly being used in water resource management worldwide, and currently in South Africa, policy and legislation are being drafted to reflect this international trend. While standard toxicity test methods and test organisms are being considered to develop and set water quality guidelines and effluent discharge limits, it is not clear whether guidelines and discharge limits set using these standard test organisms will be sufficient to protect South Africa’s scarce water resources. As part of ongoing research to investigate the use of indigenous riverine organisms as toxicity test organisms a number of potential species have been identified, including the freshwater shrimp Caridina nilotica. For much of the history of aquatic toxicological data the bulk of the data has been generated by acute toxicity testing, based on short exposures and using mortality as the response end point. There are relatively few chronic, longterm tests with sub-lethal endpoints. However, it was recognized that information about longer exposure durations and non lethal response endpoints was needed, instead of mortality. Chronic tests can provide a more environmentally realistic measure of chemical toxicity than acute toxicity tests. Caridina nilotica has been identified as a potential standard toxicity test organism, as it is widely distributed, easy to find and it occurs in flowing waters. It is an indigenous species which can be easily cultured and maintained in the laboratory and is also ecologically important. Both adults and juveniles have been used successfully in acute toxicity tests at the Institute for Water Research (Rhodes University) and the ability to rear the organisms under laboratory conditions has allowed the development of chronic toxicity tests using C. nilotica. Chronic early life stage tests include continuous exposure of the early life stages, which are presumed to be the most sensitive for aquatic organisms. This study reports on the embryonic development of C. nilotica at the culture temperature of 24⁰C. Morphological developmental stages were monitored and measured and 7 developmental stages were identified. Based on the measurements of the features that were identified, toxicity tests using the reference chemicals sodium chloride (NaCl), sodium sulphate (Na₂SO₄) and cadmium chloride (CdCl₂) were undertaken to test the suitability of C. nilotica embryonic development for chronic toxicity tests for use in water resource management. The length, width, length:width ratios and area of the features decreased in size when exposed to the chemicals. The Lowest Observed Effect Concentration (LOEC) values were 2000mg/L for Na₂SO₄, 3000mg/L for NaCl and 0.31mg/L for CdCl₂. The No Observed Effect Concentration (NOEC) values were 1000mg/L for Na₂SO₄, 2000mg/L for NaCl and <0.31mg/L for CdCl₂. Further research on the teratogenic effects of single chemicals and industrial effluent on developing C. nilotica embryos needs to be undertaken in order to evaluate the described test protocol for use in water resource management.
- Full Text:
- Authors: Ketse, Noziphiwo
- Date: 2007
- Subjects: Toxicity testing -- South Africa , Shrimp fisheries -- South Africa , Decapoda , Caridina , Water quality management -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:6025 , http://hdl.handle.net/10962/d1005367 , Toxicity testing -- South Africa , Shrimp fisheries -- South Africa , Decapoda , Caridina , Water quality management -- South Africa
- Description: Aquatic toxicity tests are increasingly being used in water resource management worldwide, and currently in South Africa, policy and legislation are being drafted to reflect this international trend. While standard toxicity test methods and test organisms are being considered to develop and set water quality guidelines and effluent discharge limits, it is not clear whether guidelines and discharge limits set using these standard test organisms will be sufficient to protect South Africa’s scarce water resources. As part of ongoing research to investigate the use of indigenous riverine organisms as toxicity test organisms a number of potential species have been identified, including the freshwater shrimp Caridina nilotica. For much of the history of aquatic toxicological data the bulk of the data has been generated by acute toxicity testing, based on short exposures and using mortality as the response end point. There are relatively few chronic, longterm tests with sub-lethal endpoints. However, it was recognized that information about longer exposure durations and non lethal response endpoints was needed, instead of mortality. Chronic tests can provide a more environmentally realistic measure of chemical toxicity than acute toxicity tests. Caridina nilotica has been identified as a potential standard toxicity test organism, as it is widely distributed, easy to find and it occurs in flowing waters. It is an indigenous species which can be easily cultured and maintained in the laboratory and is also ecologically important. Both adults and juveniles have been used successfully in acute toxicity tests at the Institute for Water Research (Rhodes University) and the ability to rear the organisms under laboratory conditions has allowed the development of chronic toxicity tests using C. nilotica. Chronic early life stage tests include continuous exposure of the early life stages, which are presumed to be the most sensitive for aquatic organisms. This study reports on the embryonic development of C. nilotica at the culture temperature of 24⁰C. Morphological developmental stages were monitored and measured and 7 developmental stages were identified. Based on the measurements of the features that were identified, toxicity tests using the reference chemicals sodium chloride (NaCl), sodium sulphate (Na₂SO₄) and cadmium chloride (CdCl₂) were undertaken to test the suitability of C. nilotica embryonic development for chronic toxicity tests for use in water resource management. The length, width, length:width ratios and area of the features decreased in size when exposed to the chemicals. The Lowest Observed Effect Concentration (LOEC) values were 2000mg/L for Na₂SO₄, 3000mg/L for NaCl and 0.31mg/L for CdCl₂. The No Observed Effect Concentration (NOEC) values were 1000mg/L for Na₂SO₄, 2000mg/L for NaCl and <0.31mg/L for CdCl₂. Further research on the teratogenic effects of single chemicals and industrial effluent on developing C. nilotica embryos needs to be undertaken in order to evaluate the described test protocol for use in water resource management.
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The European Union trade, development and cooperation agreement (TDCA) with South Africa : promoting development or self interest?
- Authors: Mavura, Mike Tigere
- Date: 2007
- Subjects: European Union Economic development -- South Africa European Union countries -- Foreign economic relations -- South Africa South Africa -- Foreign economic relations -- European Union countries
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2859 , http://hdl.handle.net/10962/d1007572
- Description: This research analyses development cooperation between the European Union (EU) and South Africa with the objective of determining which between the two entities, ultimately benefits more out of this arrangement The research goes beyond the altruistic reasons offered by the EU as the rationale for development cooperation to investigate whether South Africa's development is actually being promoted by this cooperation. Further, the research investigates whether there is also EU self-interest that informs this development cooperation. This research is conceptualised within the development aid debate framework. The research argues that this development cooperation is important to South Africa even though its impact is in real terms has not been extensive due to a number of factors. It further contends that there are EU political, security and economic interests amongst others that are being promoted by this development cooperation. The research concludes by asserting that this development cooperation promotes the mutual interests of the EU and South Africa. This conclusion challenges the paradigms of the debate on development aid which is premised in black and white terms of development aid promoting either donor or recipient interests.
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- Authors: Mavura, Mike Tigere
- Date: 2007
- Subjects: European Union Economic development -- South Africa European Union countries -- Foreign economic relations -- South Africa South Africa -- Foreign economic relations -- European Union countries
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2859 , http://hdl.handle.net/10962/d1007572
- Description: This research analyses development cooperation between the European Union (EU) and South Africa with the objective of determining which between the two entities, ultimately benefits more out of this arrangement The research goes beyond the altruistic reasons offered by the EU as the rationale for development cooperation to investigate whether South Africa's development is actually being promoted by this cooperation. Further, the research investigates whether there is also EU self-interest that informs this development cooperation. This research is conceptualised within the development aid debate framework. The research argues that this development cooperation is important to South Africa even though its impact is in real terms has not been extensive due to a number of factors. It further contends that there are EU political, security and economic interests amongst others that are being promoted by this development cooperation. The research concludes by asserting that this development cooperation promotes the mutual interests of the EU and South Africa. This conclusion challenges the paradigms of the debate on development aid which is premised in black and white terms of development aid promoting either donor or recipient interests.
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The impact of load and frequency on the biomechanical, physiological and perceptual responses to dynamic pushing
- Authors: Cripwell, Adam Michael
- Date: 2007
- Subjects: Work -- Physiological aspects , Psychophysiology , Human engineering , Biomechanics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5144 , http://hdl.handle.net/10962/d1008183 , Work -- Physiological aspects , Psychophysiology , Human engineering , Biomechanics
- Description: The objective of the present research was to establish the biomechanical, physiological and perceptual responses of male operators to dynamic pushing tasks. The pushing tasks were performed using an industrial pallet jack with varying load/frequency combinations, in a controlled laboratory environment. Thirty healthy male subjects comprised the sample. Experimental procedures were conducted utilising the Chatillon ™ Dynamometer to measure force output in the initial, sustained and ending phases. The K4b2 Ergospirometer was used to assess physiological responses (heart rate and oxygen consumption [V02])' Nine recorded forces and nine experimental conditions formed the basis of this study, with subjects required to push three loads (200kg, 350kg, 500kg) at three frequencies (1120 sec, 1/40 sec, 1/60 sec) at a speed of 3.6km.h-1 over 14 metres on a co-efficient of friction controlled walkway for six minutes. Gait analysis, along with perceptions of exertion (,Central ' and 'Local' RPE) were collected during the third and sixth minutes of each condition . Body discomfort and contribution were identified upon completion of each condition. The results demonstrated that load and frequency interacted to influence responses within each domain. Increasing loads required increased force output during each stage of the push, which had a concomitant effect on physiological and perceptual responses. Significant differences arose between the initial, sustained and ending forces for each load, showing the direct relationship between load and force exertion. The combination of heaviest load/quickest frequency required the greatest physiological output, exceeding recommended guidelines for heart rate, V02 and energy expenditure responses. Intermediate combinations required moderate and acceptable energy cost. Linear relationships were established between heart rate and oxygen consumption , as well as between load and V02 , thus providing industrial practitioners an opportunity to evaluate task demands in situ. The combination of high forces and elevated physiological responses increased the subjective rating of the condition. The results emphasise the need to holistically consider all contributing factors in a dynamic pushing task. Dynamic pushing tasks place biomechanical, physiological and perceptual demands on the human operator, which must be minimised in order to ensure that this form of manual materials handling becomes sustainable in the long term.
- Full Text:
- Authors: Cripwell, Adam Michael
- Date: 2007
- Subjects: Work -- Physiological aspects , Psychophysiology , Human engineering , Biomechanics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5144 , http://hdl.handle.net/10962/d1008183 , Work -- Physiological aspects , Psychophysiology , Human engineering , Biomechanics
- Description: The objective of the present research was to establish the biomechanical, physiological and perceptual responses of male operators to dynamic pushing tasks. The pushing tasks were performed using an industrial pallet jack with varying load/frequency combinations, in a controlled laboratory environment. Thirty healthy male subjects comprised the sample. Experimental procedures were conducted utilising the Chatillon ™ Dynamometer to measure force output in the initial, sustained and ending phases. The K4b2 Ergospirometer was used to assess physiological responses (heart rate and oxygen consumption [V02])' Nine recorded forces and nine experimental conditions formed the basis of this study, with subjects required to push three loads (200kg, 350kg, 500kg) at three frequencies (1120 sec, 1/40 sec, 1/60 sec) at a speed of 3.6km.h-1 over 14 metres on a co-efficient of friction controlled walkway for six minutes. Gait analysis, along with perceptions of exertion (,Central ' and 'Local' RPE) were collected during the third and sixth minutes of each condition . Body discomfort and contribution were identified upon completion of each condition. The results demonstrated that load and frequency interacted to influence responses within each domain. Increasing loads required increased force output during each stage of the push, which had a concomitant effect on physiological and perceptual responses. Significant differences arose between the initial, sustained and ending forces for each load, showing the direct relationship between load and force exertion. The combination of heaviest load/quickest frequency required the greatest physiological output, exceeding recommended guidelines for heart rate, V02 and energy expenditure responses. Intermediate combinations required moderate and acceptable energy cost. Linear relationships were established between heart rate and oxygen consumption , as well as between load and V02 , thus providing industrial practitioners an opportunity to evaluate task demands in situ. The combination of high forces and elevated physiological responses increased the subjective rating of the condition. The results emphasise the need to holistically consider all contributing factors in a dynamic pushing task. Dynamic pushing tasks place biomechanical, physiological and perceptual demands on the human operator, which must be minimised in order to ensure that this form of manual materials handling becomes sustainable in the long term.
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The implementation of formative assessment policies in two Grade 10 life science classrooms in the Keetmanshoop district
- Authors: Van Neel, Adrian Richerd
- Date: 2007
- Subjects: Life sciences -- Study and teaching -- Namibia Education -- Namibia Educational change -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1841 , http://hdl.handle.net/10962/d1004371
- Description: This research project investigates the implementation of formative assessment policies in the Life Science curriculum at two schools in the Keetmanshoop District, Karas Education Region. It takes the form of an interpretive case study and adopts a qualitative approach. Several data collection tools were used: classroom observation, document analysis and semi-structured interviews. Two of the eleven schools in the Karas Region offering Grade 10 Life Science were selected for the study, and the research participants at each school consisted of one Grade 10 Life Science teacher and five of their learners. The study situates itself in the context of Namibian educational reform by reviewing relevant literature pertaining to learner-centred (constructivist) education and assessment practices in pre- and post-independent Namibia. The study highlights issues pertaining to formative assessment that are at variance with reform policies, identifying six recurring themes that explain how formative assessment policies are implemented. These are teachers' perceptions of formative assessment and its role in teaching and learning, the type of learning being developed, marking/assessing assessment tasks, the integration of formative assessment into classroom instruction, strategies teachers used to implement formative assessment, and types and purpose of activities. The themes that evolved during the data gathering process provide insight into the ways in which teachers perceive formative assessment in relation to the ideals of Namibian educational reform policies. In the light of these findings, the study makes recommendations concerning the implementation of formative assessment policies so as to render these congruent with the theory underpinning leamer-centred education.
- Full Text:
- Authors: Van Neel, Adrian Richerd
- Date: 2007
- Subjects: Life sciences -- Study and teaching -- Namibia Education -- Namibia Educational change -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1841 , http://hdl.handle.net/10962/d1004371
- Description: This research project investigates the implementation of formative assessment policies in the Life Science curriculum at two schools in the Keetmanshoop District, Karas Education Region. It takes the form of an interpretive case study and adopts a qualitative approach. Several data collection tools were used: classroom observation, document analysis and semi-structured interviews. Two of the eleven schools in the Karas Region offering Grade 10 Life Science were selected for the study, and the research participants at each school consisted of one Grade 10 Life Science teacher and five of their learners. The study situates itself in the context of Namibian educational reform by reviewing relevant literature pertaining to learner-centred (constructivist) education and assessment practices in pre- and post-independent Namibia. The study highlights issues pertaining to formative assessment that are at variance with reform policies, identifying six recurring themes that explain how formative assessment policies are implemented. These are teachers' perceptions of formative assessment and its role in teaching and learning, the type of learning being developed, marking/assessing assessment tasks, the integration of formative assessment into classroom instruction, strategies teachers used to implement formative assessment, and types and purpose of activities. The themes that evolved during the data gathering process provide insight into the ways in which teachers perceive formative assessment in relation to the ideals of Namibian educational reform policies. In the light of these findings, the study makes recommendations concerning the implementation of formative assessment policies so as to render these congruent with the theory underpinning leamer-centred education.
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The influence of Micro-Finance Institutions (MFIs) on Micro and Small Enterprises (MSEs) in Kenya
- Authors: Ngatia, Ndiritu
- Date: 2007
- Subjects: Microfinance -- Kenya Financial institutions -- Kenya Small business -- Kenya
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:822 , http://hdl.handle.net/10962/d1009436
- Description: In Kenya, like in many developing countries, Micro and Small Enterprises (MSEs) have become the main focus for achieving the much-needed social and economic development and alleviating poverty. However, their development has been hampered by lack of access to appropriate financial and related services. Micro financing has been seen as a viable alternative to providing financial services to entrepreneurs in the MSE sector. The focus of this study was to explore the role of MFIs in the development of MSEs and to see if there are ways in which this role can be enhanced to better support the growth of MSEs. Such enhancement would contribute greatly towards government efforts to foster social-economic development. The results of the research indicate that generally, MFIs appear to have positively influenced the growth of MSE in Kenya and have potential to further influence MSE growth. There were however a number areas that if paid attention to could enhance this influence. These include the need for MFIs to offer supportive services as opposed to merely credit facilities to MSEs and the need for government intervention by putting in place a suitable Act to regulate the operations of MFIs.
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- Authors: Ngatia, Ndiritu
- Date: 2007
- Subjects: Microfinance -- Kenya Financial institutions -- Kenya Small business -- Kenya
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:822 , http://hdl.handle.net/10962/d1009436
- Description: In Kenya, like in many developing countries, Micro and Small Enterprises (MSEs) have become the main focus for achieving the much-needed social and economic development and alleviating poverty. However, their development has been hampered by lack of access to appropriate financial and related services. Micro financing has been seen as a viable alternative to providing financial services to entrepreneurs in the MSE sector. The focus of this study was to explore the role of MFIs in the development of MSEs and to see if there are ways in which this role can be enhanced to better support the growth of MSEs. Such enhancement would contribute greatly towards government efforts to foster social-economic development. The results of the research indicate that generally, MFIs appear to have positively influenced the growth of MSE in Kenya and have potential to further influence MSE growth. There were however a number areas that if paid attention to could enhance this influence. These include the need for MFIs to offer supportive services as opposed to merely credit facilities to MSEs and the need for government intervention by putting in place a suitable Act to regulate the operations of MFIs.
- Full Text: