'Visible hectares, vanishing livelihoods': a case of the fast track land reform and resettlement programme in Southern Matabeleland- Zimbabwe
- Authors: Mabhena, Clifford
- Date: 2010
- Subjects: Sustainable development -- Zimbabwe , Rural poor -- Zimbabwe , Rural development -- Zimbabwe , Land tenure -- Zimbabwe , Land reform beneficiaries -- Zimbabwe , Livestock -- Breeding -- Zimbabwe , Land settlement -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , D Soc Sc
- Identifier: vital:11423 , http://hdl.handle.net/10353/d1001193 , Sustainable development -- Zimbabwe , Rural poor -- Zimbabwe , Rural development -- Zimbabwe , Land tenure -- Zimbabwe , Land reform beneficiaries -- Zimbabwe , Livestock -- Breeding -- Zimbabwe , Land settlement -- Zimbabwe
- Description: Land reform has been going on in Zimbabwe since the state attained independence from Britain in 1980 as a way of enhancing agrarian livelihoods for the formerly marginalized people. This study argues that, the Land Reform Programme in Southern Matabeleland rather than enhancing agrarian livelihoods, well established livelihoods have actually been drastically reduced. This has been exacerbated by the state programme of land re-distribution that prescribes a „one size fits all‟ model. Yet this is contrary to the thinking in development discourse that equitable land distribution increases rural livelihoods. As a way of gathering data this study utilized ethnography and case study methodologies. I spent two years interacting and interviewing purposively selected new resettles, communal residents, migrant workers and gold panners in this region. Results from this study confirm that, land reform has greatly reduced livelihoods, particularly agrarian livelihoods. Also, this research has found out that, the majority of residents now depend on off-farm livelihoods such as gold panning and migration to neighbouring South Africa. This thesis therefore concludes that, despite a massive expropriation of former commercial farms, people of Southern Matabeleland have not benefitted much as the village settlements (A1) and the small size farms (A2) have not received support from this live-stocking community. People in this region pin their hopes on livestock rearing to sustain their livelihoods and this study therefore recommends that, any agrarian transformation programmes should address the issues that promote livestock rearing
- Full Text:
- Date Issued: 2010
- Authors: Mabhena, Clifford
- Date: 2010
- Subjects: Sustainable development -- Zimbabwe , Rural poor -- Zimbabwe , Rural development -- Zimbabwe , Land tenure -- Zimbabwe , Land reform beneficiaries -- Zimbabwe , Livestock -- Breeding -- Zimbabwe , Land settlement -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , D Soc Sc
- Identifier: vital:11423 , http://hdl.handle.net/10353/d1001193 , Sustainable development -- Zimbabwe , Rural poor -- Zimbabwe , Rural development -- Zimbabwe , Land tenure -- Zimbabwe , Land reform beneficiaries -- Zimbabwe , Livestock -- Breeding -- Zimbabwe , Land settlement -- Zimbabwe
- Description: Land reform has been going on in Zimbabwe since the state attained independence from Britain in 1980 as a way of enhancing agrarian livelihoods for the formerly marginalized people. This study argues that, the Land Reform Programme in Southern Matabeleland rather than enhancing agrarian livelihoods, well established livelihoods have actually been drastically reduced. This has been exacerbated by the state programme of land re-distribution that prescribes a „one size fits all‟ model. Yet this is contrary to the thinking in development discourse that equitable land distribution increases rural livelihoods. As a way of gathering data this study utilized ethnography and case study methodologies. I spent two years interacting and interviewing purposively selected new resettles, communal residents, migrant workers and gold panners in this region. Results from this study confirm that, land reform has greatly reduced livelihoods, particularly agrarian livelihoods. Also, this research has found out that, the majority of residents now depend on off-farm livelihoods such as gold panning and migration to neighbouring South Africa. This thesis therefore concludes that, despite a massive expropriation of former commercial farms, people of Southern Matabeleland have not benefitted much as the village settlements (A1) and the small size farms (A2) have not received support from this live-stocking community. People in this region pin their hopes on livestock rearing to sustain their livelihoods and this study therefore recommends that, any agrarian transformation programmes should address the issues that promote livestock rearing
- Full Text:
- Date Issued: 2010
A case study : exploring a DVD driven approach for teaching and learning mathematics, at secondary school level, with a framework of blended learning
- Authors: Padayachee, Pragashni
- Date: 2010
- Subjects: Matehmatics -- Study and Teaching (Secondary) -- Audio-visual aids , Matehmatics -- Study and Teaching (Secondary) -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10504 , http://hdl.handle.net/10948/1384 , Matehmatics -- Study and Teaching (Secondary) -- Audio-visual aids , Matehmatics -- Study and Teaching (Secondary) -- South Africa -- Port Elizabeth
- Description: Post-apartheid South Africa is witnessing an education crisis of significant proportions. The new outcomes-based education system has failed to deliver and universities are suffering the consequences of under-preparation of learners for tertiary studies especially in mathematics. The educator corps is lacking and it has become common practice for universities to deploy augmented programmes in mathematics for secondary school learners in the surrounding areas. This thesis describes a particular approach of blended learning, devised for the Incubator School Project (ISP), an initiative of the Nelson Mandela Metropolitan University (NMMU) in the Eastern Cape of South Africa. The defining feature of this blended approach is that it incorporates DVD technology, which offers an affordable and accessible option for the particular group of learners and the schools they attend. The thesis poses the research question: How did the use of the DVD approach within a blended learning environment support the learning of mathematics? This case study explores the particular blended approach and reports six fold on the approach – qualitatively based firstly on a questionnaire completed by learners and secondly on interviews of learners, thirdly on the facilitators reports, fourthly quantitatively on learner performance before and after the intervention. Fifthly six schools are used as a case study where the mathematics performance of the learners who participated in the ISP is compared to those who did not participate in the ISP. Finally the scope of blending of this model is evaluated by means of a radar chart, adapted from an existing radar measure. This research revealed that using the DVD approach within a blended learning environment did lead to an improvement in learners perceptions about mathematics, an improvement in the manner in which they learned mathematics, an extension in their mathematics knowledge and provided learners with a supportive environment in which to learn mathematics. The elements which supported learning in this approach are presented. The findings of the study suggest that this approach impacted favourably on the mathematics learning and enhanced the mathematics learning and performance of these learners. Recommendations are offered for practice, teachers and schools and for further research possibilities.
- Full Text:
- Date Issued: 2010
- Authors: Padayachee, Pragashni
- Date: 2010
- Subjects: Matehmatics -- Study and Teaching (Secondary) -- Audio-visual aids , Matehmatics -- Study and Teaching (Secondary) -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10504 , http://hdl.handle.net/10948/1384 , Matehmatics -- Study and Teaching (Secondary) -- Audio-visual aids , Matehmatics -- Study and Teaching (Secondary) -- South Africa -- Port Elizabeth
- Description: Post-apartheid South Africa is witnessing an education crisis of significant proportions. The new outcomes-based education system has failed to deliver and universities are suffering the consequences of under-preparation of learners for tertiary studies especially in mathematics. The educator corps is lacking and it has become common practice for universities to deploy augmented programmes in mathematics for secondary school learners in the surrounding areas. This thesis describes a particular approach of blended learning, devised for the Incubator School Project (ISP), an initiative of the Nelson Mandela Metropolitan University (NMMU) in the Eastern Cape of South Africa. The defining feature of this blended approach is that it incorporates DVD technology, which offers an affordable and accessible option for the particular group of learners and the schools they attend. The thesis poses the research question: How did the use of the DVD approach within a blended learning environment support the learning of mathematics? This case study explores the particular blended approach and reports six fold on the approach – qualitatively based firstly on a questionnaire completed by learners and secondly on interviews of learners, thirdly on the facilitators reports, fourthly quantitatively on learner performance before and after the intervention. Fifthly six schools are used as a case study where the mathematics performance of the learners who participated in the ISP is compared to those who did not participate in the ISP. Finally the scope of blending of this model is evaluated by means of a radar chart, adapted from an existing radar measure. This research revealed that using the DVD approach within a blended learning environment did lead to an improvement in learners perceptions about mathematics, an improvement in the manner in which they learned mathematics, an extension in their mathematics knowledge and provided learners with a supportive environment in which to learn mathematics. The elements which supported learning in this approach are presented. The findings of the study suggest that this approach impacted favourably on the mathematics learning and enhanced the mathematics learning and performance of these learners. Recommendations are offered for practice, teachers and schools and for further research possibilities.
- Full Text:
- Date Issued: 2010
A chemo-enzymatic process for the production of beta-thymidine, a key intermediate in antiretrovirol manufacture
- Gordon, Gregory Ernest Robert
- Authors: Gordon, Gregory Ernest Robert
- Date: 2010
- Subjects: HIV infections -- Treatment -- South Africa , HIV infections -- South Africa -- Prevention , Antiretroviral agents
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:10423 , http://hdl.handle.net/10948/d1016217
- Description: The socio-economic impact of HIV/AIDS on South Africa has resulted in lower gross domestic product, loss of skills in key sectors such as education, and increased health-care costs in providing access to treatment. Currently active pharmaceutical ingredients (API’s) such as stavudine (d4T) and azidothymidine (AZT) are imported from India and China, while formulation is conducted locally. A strategy was initiated between CSIR Biosciences and LIFElab under the auspices of Arvir Technologies to investigate the feasibility of local antiretroviral manufacture (d4T and AZT) or the manufacture of a key intermediate such as β- thymidine (dT). Several advantages associated with successful implementation of this strategy include ensuring a local supply of API’s, thus reducing reliance on procurement from foreign sources and reducing the effect of foreign exchange rate fluctuations on providing cost effective access to treatment. A local supply source would also reduce the imports and thus aid the balance of payments deficit, and in addition to this, provide stimulus in the local pharmaceutical manufacturing industry (which has been in decline for several decades), resulting in increased skills and employment opportunities. This thesis describes the development of a superior chemo-enzymatic process for the production of β-thymidine (72 percent yield, prior to isolation), a key intermediate in the preparation of anti-retrovirals. Alternative processes based purely on chemical or bioprocess transformations to prepare either 5-methyluridine (5-MU) or dT suffer from several disadvantages: lengthy transformations due to protection/deprotection strategies, low selectivties and product yields (30 percent in the chemical process) and isolation of the product from dilute process streams requiring the use of large uneconomical reactors (bioprocesss). This contributes significantly to the cost of d4T and AZT manufacture. Our novel chemoenzymatic process comprises of a biocatalytic reaction for the production of 5-MU, with subsequent chemical transformation into dT (3 steps) negating and circumventing the limitations of the chemical or bioprocess routes. During the course of this project development, the β-thymidine selling price declined from 175 $/kg (2005) to 100 $/kg (2008). However, the process described in this work is still competitive based on the current β- thymidine selling price of 100 $/kg. The process economics show that with further optimization and increasing the isolated dT yield from 70 percent to 90 percent, the variable cost decreases from 136 $/kg to 110 $/kg. The increase in isolated yield is highly probable, based on solubility data of β-thymidine. The decrease in β-thymidine selling price and technological improvement in dT manufacture should translate into lower API manufacture costs and more cost effective access to treatment. Our novel biocatalytic process producing 5-MU uses a coupled enzyme system employing PNP, Purine Nucleoside Phosphorylase and PyNP, Pyrimidine Nucleoside Phosphorylase. The overall transglycosylation reaction may be decoupled into the phosphorolysis reaction (PNP) and synthesis reaction (PyNP). During the phosphorolysis reaction, guanosine is converted into guanine and ribose-1-phosphate (R-1-P) in the presence of PNP enzyme. The reaction intermediate R-1-P is then coupled to thymine in the presence of PyNP enzyme during the synthesis reaction, producing 5-MU. The process was scaled up from lab-scale to bench-scale (10 - 20 L) and demonstrated to be robust and reproducible. This is evident from the average guanosine conversion (94.7 percent ± 2.03) and 5-MU yield (88.2 percent ± 6.21) and mole balance (104 percent ± 7.61) which were obtained at bench-scale (3 replicates, 10 L). The reaction was carried out at reactor productivities of between 7 – 11 g.L-1.h-1. The integration of the biocatalytic process and chemical processes was successfully carried out, showing that 5-MU produced using our novel biocatalytic process behaved similarly to commercially available 5- MU (ex. Dayang Chemicals, China). A PCT patent application (Ref. No. P44422PC01) on this chemo-enzymatic process has been filed and currently public private partnerships are being explored through Arvir Technologies to evaluate and validate this technology at one ton scale.
- Full Text:
- Date Issued: 2010
- Authors: Gordon, Gregory Ernest Robert
- Date: 2010
- Subjects: HIV infections -- Treatment -- South Africa , HIV infections -- South Africa -- Prevention , Antiretroviral agents
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:10423 , http://hdl.handle.net/10948/d1016217
- Description: The socio-economic impact of HIV/AIDS on South Africa has resulted in lower gross domestic product, loss of skills in key sectors such as education, and increased health-care costs in providing access to treatment. Currently active pharmaceutical ingredients (API’s) such as stavudine (d4T) and azidothymidine (AZT) are imported from India and China, while formulation is conducted locally. A strategy was initiated between CSIR Biosciences and LIFElab under the auspices of Arvir Technologies to investigate the feasibility of local antiretroviral manufacture (d4T and AZT) or the manufacture of a key intermediate such as β- thymidine (dT). Several advantages associated with successful implementation of this strategy include ensuring a local supply of API’s, thus reducing reliance on procurement from foreign sources and reducing the effect of foreign exchange rate fluctuations on providing cost effective access to treatment. A local supply source would also reduce the imports and thus aid the balance of payments deficit, and in addition to this, provide stimulus in the local pharmaceutical manufacturing industry (which has been in decline for several decades), resulting in increased skills and employment opportunities. This thesis describes the development of a superior chemo-enzymatic process for the production of β-thymidine (72 percent yield, prior to isolation), a key intermediate in the preparation of anti-retrovirals. Alternative processes based purely on chemical or bioprocess transformations to prepare either 5-methyluridine (5-MU) or dT suffer from several disadvantages: lengthy transformations due to protection/deprotection strategies, low selectivties and product yields (30 percent in the chemical process) and isolation of the product from dilute process streams requiring the use of large uneconomical reactors (bioprocesss). This contributes significantly to the cost of d4T and AZT manufacture. Our novel chemoenzymatic process comprises of a biocatalytic reaction for the production of 5-MU, with subsequent chemical transformation into dT (3 steps) negating and circumventing the limitations of the chemical or bioprocess routes. During the course of this project development, the β-thymidine selling price declined from 175 $/kg (2005) to 100 $/kg (2008). However, the process described in this work is still competitive based on the current β- thymidine selling price of 100 $/kg. The process economics show that with further optimization and increasing the isolated dT yield from 70 percent to 90 percent, the variable cost decreases from 136 $/kg to 110 $/kg. The increase in isolated yield is highly probable, based on solubility data of β-thymidine. The decrease in β-thymidine selling price and technological improvement in dT manufacture should translate into lower API manufacture costs and more cost effective access to treatment. Our novel biocatalytic process producing 5-MU uses a coupled enzyme system employing PNP, Purine Nucleoside Phosphorylase and PyNP, Pyrimidine Nucleoside Phosphorylase. The overall transglycosylation reaction may be decoupled into the phosphorolysis reaction (PNP) and synthesis reaction (PyNP). During the phosphorolysis reaction, guanosine is converted into guanine and ribose-1-phosphate (R-1-P) in the presence of PNP enzyme. The reaction intermediate R-1-P is then coupled to thymine in the presence of PyNP enzyme during the synthesis reaction, producing 5-MU. The process was scaled up from lab-scale to bench-scale (10 - 20 L) and demonstrated to be robust and reproducible. This is evident from the average guanosine conversion (94.7 percent ± 2.03) and 5-MU yield (88.2 percent ± 6.21) and mole balance (104 percent ± 7.61) which were obtained at bench-scale (3 replicates, 10 L). The reaction was carried out at reactor productivities of between 7 – 11 g.L-1.h-1. The integration of the biocatalytic process and chemical processes was successfully carried out, showing that 5-MU produced using our novel biocatalytic process behaved similarly to commercially available 5- MU (ex. Dayang Chemicals, China). A PCT patent application (Ref. No. P44422PC01) on this chemo-enzymatic process has been filed and currently public private partnerships are being explored through Arvir Technologies to evaluate and validate this technology at one ton scale.
- Full Text:
- Date Issued: 2010
A combination of platinum anticancer drugs and mangiferin causes increased efficacy in cancer cell lines
- Authors: Du Plessis-Stoman, Debbie
- Date: 2010
- Subjects: Cancer -- Chemotherapy , Antineoplastic agents , Platinum compounds -- Therapeutic use , Cancer cells
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10338 , http://hdl.handle.net/10948/d1016160
- Description: This thesis mainly deals with some biochemical aspects regarding the efficacy of novel platinum anticancer compounds alone and in combination with mangiferin, as part of a broader study in which both chemistry and biochemistry are involved. Various novel diamine and N-S donor chelate compounds of platinum II and IV have been developed in which factors such as stereochemistry, ligand exchange rate and biocompatibility were considered as additional parameters. In the first order testing, each of these compounds was tested with reference to their “killing” potential by comparing their rate of killing, over a period of 48 hours with those of cisplatin and oxaliplatin. Numerous novel compounds were tested in this way, using the MTT cell viability assay and the three cancer cell lines MCF7, HT29 and HeLa. Although only a few could be regarded as equal to or even better than cisplatin, CPA7 and oxaliplatin, the testing of these compounds on cancer cells provided useful knowledge for the further development of novel compounds. Three of the better compounds, namely Yol 25, Yol 29.1 and Mar 4.1.4 were selected for further studies, together with oxaliplatin and CPA7 as positive controls, to obtain more detailed knowledge of their anticancer action, both alone and when applied in combination with mangiferin. In addition to the above, resistant cells were produced for each of the three different cell lines tested and all the selected compounds, both in the presence and absence of mangiferin. The effects of these treatments on the activation of NFĸB when applied to normal and resistant cell lines were also investigated. All the compounds induced apoptosis in the cell lines tested as well as alter the DNA cycle at one or more phase. Additionally, combination of these compounds with mangiferin enhanced the above-mentioned effects. Mangiferin decreases the IC50 values of the platinum drugs by up to 3.4 times and, although mangiferin alone did not induce cell cycle arrest, the presence of mangiferin in combination with oxaliplatin and Yol 25 shows an earlier and greatly enhanced delay in the S-phase, while cells treated with CPA7, Yol 29.1 and Mar 4.1.4 in combination with mangiferin showed a later, but greatly enhanced delay in the S-phase. It was also found that mangiferin acts as an NFĸB inhibitor when applied in combination with these drugs, which, in turn, reduces the occurrence of resistance in the cell lines. Resistance to oxaliplatin was counteracted by the combination with mangiferin in HeLa and HT29, but not in MCF7 cells, while resistance to CPA7 was only counteracted in the MCF7 cell line. Yol 25 and Mar 4.1.4 did not seem to induce resistance in HeLa and MCF7 cells, but did in HT29 cells, whereas Yol 29.1 caused resistance in HeLa and HT29 cells, but not in MCF7 cells. Finally, an effort was made to evaluate the different compounds by comparing them with respect to their properties relating to anticancer action with and without the addition of mangiferin.
- Full Text:
- Date Issued: 2010
- Authors: Du Plessis-Stoman, Debbie
- Date: 2010
- Subjects: Cancer -- Chemotherapy , Antineoplastic agents , Platinum compounds -- Therapeutic use , Cancer cells
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10338 , http://hdl.handle.net/10948/d1016160
- Description: This thesis mainly deals with some biochemical aspects regarding the efficacy of novel platinum anticancer compounds alone and in combination with mangiferin, as part of a broader study in which both chemistry and biochemistry are involved. Various novel diamine and N-S donor chelate compounds of platinum II and IV have been developed in which factors such as stereochemistry, ligand exchange rate and biocompatibility were considered as additional parameters. In the first order testing, each of these compounds was tested with reference to their “killing” potential by comparing their rate of killing, over a period of 48 hours with those of cisplatin and oxaliplatin. Numerous novel compounds were tested in this way, using the MTT cell viability assay and the three cancer cell lines MCF7, HT29 and HeLa. Although only a few could be regarded as equal to or even better than cisplatin, CPA7 and oxaliplatin, the testing of these compounds on cancer cells provided useful knowledge for the further development of novel compounds. Three of the better compounds, namely Yol 25, Yol 29.1 and Mar 4.1.4 were selected for further studies, together with oxaliplatin and CPA7 as positive controls, to obtain more detailed knowledge of their anticancer action, both alone and when applied in combination with mangiferin. In addition to the above, resistant cells were produced for each of the three different cell lines tested and all the selected compounds, both in the presence and absence of mangiferin. The effects of these treatments on the activation of NFĸB when applied to normal and resistant cell lines were also investigated. All the compounds induced apoptosis in the cell lines tested as well as alter the DNA cycle at one or more phase. Additionally, combination of these compounds with mangiferin enhanced the above-mentioned effects. Mangiferin decreases the IC50 values of the platinum drugs by up to 3.4 times and, although mangiferin alone did not induce cell cycle arrest, the presence of mangiferin in combination with oxaliplatin and Yol 25 shows an earlier and greatly enhanced delay in the S-phase, while cells treated with CPA7, Yol 29.1 and Mar 4.1.4 in combination with mangiferin showed a later, but greatly enhanced delay in the S-phase. It was also found that mangiferin acts as an NFĸB inhibitor when applied in combination with these drugs, which, in turn, reduces the occurrence of resistance in the cell lines. Resistance to oxaliplatin was counteracted by the combination with mangiferin in HeLa and HT29, but not in MCF7 cells, while resistance to CPA7 was only counteracted in the MCF7 cell line. Yol 25 and Mar 4.1.4 did not seem to induce resistance in HeLa and MCF7 cells, but did in HT29 cells, whereas Yol 29.1 caused resistance in HeLa and HT29 cells, but not in MCF7 cells. Finally, an effort was made to evaluate the different compounds by comparing them with respect to their properties relating to anticancer action with and without the addition of mangiferin.
- Full Text:
- Date Issued: 2010
A contribution to TEC modelling over Southern Africa using GPS data
- Authors: Habarulema, John Bosco
- Date: 2010
- Subjects: Electrons -- Mathematical models Radio wave propagation Global positioning system -- Measurement Ionospheric radio wave propagation Atmospheric physics -- Africa, Southern
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5456 , http://hdl.handle.net/10962/d1005241
- Description: Modelling ionospheric total electron content (TEC) is an important area of interest for radio wave propagation, geodesy, surveying, the understanding of space weather dynamics and error correction in relation to Global Navigation Satellite Systems (GNNS) applications. With the utilisation of improved ionosonde technology coupled with the use of GNSS, the response of technological systems due to changes in the ionosphere during both quiet and disturbed conditions can be historically inferred. TEC values are usually derived from GNSS measurements using mathematically intensive algorithms. However, the techniques used to estimate these TEC values depend heavily on the availability of near-real time GNSS data, and therefore, are sometimes unable to generate complete datasets. This thesis investigated possibilities for the modelling of TEC values derived from the South African Global Positioning System (GPS)receiver network using linear regression methods and artificial neural networks (NNs). GPS TEC values were derived using the Adjusted Spherical Harmonic Analysis (ASHA) algorithm. Considering TEC and the factors that influence its variability as “dependent and independent variables” respectively, the capabilities of linear regression methods and NNs for TEC modelling were first investigated using a small dataset from two GPS receiver stations. NN and regression models were separately developed and used to reproduce TEC fluctuations at different stations not included in the models’ development. For this purpose, TEC was modelled as a function of diurnal variation, seasonal variation, solar and magnetic activities. Comparative analysis showed that NN models provide predictions of GPS TEC that were an improvement on those predicted by the regression models developed. A separate study to empirically investigate the effects of solar wind on GPS TEC was carried out. Quantitative results indicated that solar wind does not have a significant influence on TEC variability. The final TEC simulation model developed makes use of the NN technique to find the relationship between historical TEC data variations and factors that are known to influence TEC variability (such as solar and magnetic activities, diurnal and seasonal variations and the geographical locations of the respective GPS stations) for the purposes of regional TEC modelling and mapping. The NN technique in conjunction with interpolation and extrapolation methods makes it possible to construct ionospheric TEC maps and to analyse the spatial and temporal TEC behaviour over Southern Africa. For independent validation, modelled TEC values were compared to ionosonde TEC and the International Reference Ionosphere (IRI) generated TEC values during both quiet and disturbed conditions. This thesis provides a comprehensive guide on the development of TEC models for predicting ionospheric variability over the South African region, and forms a significant contribution to ionospheric modelling efforts in Africa.
- Full Text:
- Date Issued: 2010
- Authors: Habarulema, John Bosco
- Date: 2010
- Subjects: Electrons -- Mathematical models Radio wave propagation Global positioning system -- Measurement Ionospheric radio wave propagation Atmospheric physics -- Africa, Southern
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5456 , http://hdl.handle.net/10962/d1005241
- Description: Modelling ionospheric total electron content (TEC) is an important area of interest for radio wave propagation, geodesy, surveying, the understanding of space weather dynamics and error correction in relation to Global Navigation Satellite Systems (GNNS) applications. With the utilisation of improved ionosonde technology coupled with the use of GNSS, the response of technological systems due to changes in the ionosphere during both quiet and disturbed conditions can be historically inferred. TEC values are usually derived from GNSS measurements using mathematically intensive algorithms. However, the techniques used to estimate these TEC values depend heavily on the availability of near-real time GNSS data, and therefore, are sometimes unable to generate complete datasets. This thesis investigated possibilities for the modelling of TEC values derived from the South African Global Positioning System (GPS)receiver network using linear regression methods and artificial neural networks (NNs). GPS TEC values were derived using the Adjusted Spherical Harmonic Analysis (ASHA) algorithm. Considering TEC and the factors that influence its variability as “dependent and independent variables” respectively, the capabilities of linear regression methods and NNs for TEC modelling were first investigated using a small dataset from two GPS receiver stations. NN and regression models were separately developed and used to reproduce TEC fluctuations at different stations not included in the models’ development. For this purpose, TEC was modelled as a function of diurnal variation, seasonal variation, solar and magnetic activities. Comparative analysis showed that NN models provide predictions of GPS TEC that were an improvement on those predicted by the regression models developed. A separate study to empirically investigate the effects of solar wind on GPS TEC was carried out. Quantitative results indicated that solar wind does not have a significant influence on TEC variability. The final TEC simulation model developed makes use of the NN technique to find the relationship between historical TEC data variations and factors that are known to influence TEC variability (such as solar and magnetic activities, diurnal and seasonal variations and the geographical locations of the respective GPS stations) for the purposes of regional TEC modelling and mapping. The NN technique in conjunction with interpolation and extrapolation methods makes it possible to construct ionospheric TEC maps and to analyse the spatial and temporal TEC behaviour over Southern Africa. For independent validation, modelled TEC values were compared to ionosonde TEC and the International Reference Ionosphere (IRI) generated TEC values during both quiet and disturbed conditions. This thesis provides a comprehensive guide on the development of TEC models for predicting ionospheric variability over the South African region, and forms a significant contribution to ionospheric modelling efforts in Africa.
- Full Text:
- Date Issued: 2010
A critical analysis of child labour and human resource development in Uganda
- Authors: Kibukamusoke, Martha
- Date: 2010
- Subjects: Child labor -- Uganda , Child soldiers -- Uganda
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:16128 , http://hdl.handle.net/10948/1196 , Child labor -- Uganda , Child soldiers -- Uganda
- Description: This study is a critical analysis of child labour and human resource development in Uganda. The study was undertaken because of the growing concern about child-labour practices in African countries, Uganda being an example. The incidence of child labour and the form that it takes are driven by supply-anddemand factors countrywide, but also by the sheer need of children to survive. Child labour is considered to be a fundamental child development problem. Children are involved in a number of child-labour practices such as prostitution in the commercial and tourism sex industry, forced begging on the streets, and forced soldiering. They may be used as camel jockeys, domestic servants, farm labourers/herders, mine labourers, produce porters, roadside sellers/street vendors, sweetshop-industry labourers, cooks and porters for rebels. The persistent exploitation of children involved in hazardous work and conditions has become overwhelming in Uganda. Poverty as one of the major causes for the growing numbers of child labourers in the agricultural sector in Uganda has caused a number of children to engage in child-labour activities to earn extra income for household survival. Many children have opted for partial attendance in school, eventually dropping out. Parents have also frequently influenced children to work on family farms, thus contributing to the children dropping out of school. Child-labour practices have become entrenched in the social and moral fabric of Ugandan society, and for this reason, research endeavours to uncover ways and methods to reverse this situation. The main objectives of this research were to establish the impact of poverty on child labour, to assess the effect of the social and cultural setup on child labour, to find out the impact of child-labour legislation enforcement, to determine the 5 influence of the HIV and AIDS pandemic on child labour, to establish the effect of the educational system and technological advancement on child labour, to establish the level of awareness of human rights in the community, and to establish the impact of human rights activists on the prevention of child labour. The study was undertaken in Masindi District in Budongo Sub County, in three parishes, Nyabyeya, Nyantonzi and Kasongoire. The respondents used for the study included child labourers, their parents, farmers, and community leaders. The method used to get to the sample was purposive sampling. Data was collected using questionnaires for written answers and a tape recorder for oral answers. Both primary and secondary data was collected, verified, edited, checked, coded, analysed, and then exported to Excel and SPSS. Collecting the data was a challenging exercise for the researcher. Experiences were varied, in the hospitality and willingness of respondents to learn more about child issues. Although respondents were willing to participate in the data collection exercise, social and cultural values did not permit all of them to share their views with the researcher. To collect data from respondents, the researcher had to ensure that remuneration was in place at the end of the exercise. The respondents filled out the questionnaires only after learning of the availability of a reward for every questionnaire answered. More setbacks were the need to travel long distances, and enduring the poor infrastructure, poor sanitation, and epidemic outbreaks, some of which diluted the quality of data collected. During group interviews, most parents were not entirely truthful about involving their children in child-labour activities. Although most respondents had an idea of what child labour is, their ignorance levels on the topic prevented them from stopping their children from working. The major findings of the research were that the cultural, social and economic setup of the community in the study area favoured child labour, although the child-labour legislation is against using children as labourers. Various ethnicities 6 in the study area considered a person between the ages of 5 and 12 years to be a child, yet the Constitution of Uganda dictates the age of childhood to be below 18 years. This causes conflict in the definition of who a child is. Although parents were aware of the Universal Primary Education (UPE) regulation penalties for not taking children to school, they still permitted children to engage in child-labour activities, and little has been done by government to curb the culprits. Awareness of the Sub Counties and Credit Co-operatives (SACCOs) and their implementation has not helped to reduce poverty in the area studied, resulting in an increased school dropout rate among school-going-age children, as well as more child-labour activities. The major conclusion of the study was that little has been done to increase the awareness levels of the teachers, parents and their children about child labour and its legislation, their knowledge of and involvement in micro-finance institutions in the community, and the availability of vocational training institutions. Little has therefore been done to reduce child-labour activities, improve the economic status of the community, and improve their human resource skills. The major recommendations of the research to the study are that culture should not override the Constitution as far as the definition of age limit is concerned. The government should carry out stakeholder analyses, and implement a life-skills and sensitisation programme in order to improve child participation in the Universal Primary Education (UPE) programme. Government should ensure that the society is given information about basic accounting, project planning and management skills, in order to be effectively involved in the economic programmes of SACCOs.
- Full Text:
- Date Issued: 2010
- Authors: Kibukamusoke, Martha
- Date: 2010
- Subjects: Child labor -- Uganda , Child soldiers -- Uganda
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:16128 , http://hdl.handle.net/10948/1196 , Child labor -- Uganda , Child soldiers -- Uganda
- Description: This study is a critical analysis of child labour and human resource development in Uganda. The study was undertaken because of the growing concern about child-labour practices in African countries, Uganda being an example. The incidence of child labour and the form that it takes are driven by supply-anddemand factors countrywide, but also by the sheer need of children to survive. Child labour is considered to be a fundamental child development problem. Children are involved in a number of child-labour practices such as prostitution in the commercial and tourism sex industry, forced begging on the streets, and forced soldiering. They may be used as camel jockeys, domestic servants, farm labourers/herders, mine labourers, produce porters, roadside sellers/street vendors, sweetshop-industry labourers, cooks and porters for rebels. The persistent exploitation of children involved in hazardous work and conditions has become overwhelming in Uganda. Poverty as one of the major causes for the growing numbers of child labourers in the agricultural sector in Uganda has caused a number of children to engage in child-labour activities to earn extra income for household survival. Many children have opted for partial attendance in school, eventually dropping out. Parents have also frequently influenced children to work on family farms, thus contributing to the children dropping out of school. Child-labour practices have become entrenched in the social and moral fabric of Ugandan society, and for this reason, research endeavours to uncover ways and methods to reverse this situation. The main objectives of this research were to establish the impact of poverty on child labour, to assess the effect of the social and cultural setup on child labour, to find out the impact of child-labour legislation enforcement, to determine the 5 influence of the HIV and AIDS pandemic on child labour, to establish the effect of the educational system and technological advancement on child labour, to establish the level of awareness of human rights in the community, and to establish the impact of human rights activists on the prevention of child labour. The study was undertaken in Masindi District in Budongo Sub County, in three parishes, Nyabyeya, Nyantonzi and Kasongoire. The respondents used for the study included child labourers, their parents, farmers, and community leaders. The method used to get to the sample was purposive sampling. Data was collected using questionnaires for written answers and a tape recorder for oral answers. Both primary and secondary data was collected, verified, edited, checked, coded, analysed, and then exported to Excel and SPSS. Collecting the data was a challenging exercise for the researcher. Experiences were varied, in the hospitality and willingness of respondents to learn more about child issues. Although respondents were willing to participate in the data collection exercise, social and cultural values did not permit all of them to share their views with the researcher. To collect data from respondents, the researcher had to ensure that remuneration was in place at the end of the exercise. The respondents filled out the questionnaires only after learning of the availability of a reward for every questionnaire answered. More setbacks were the need to travel long distances, and enduring the poor infrastructure, poor sanitation, and epidemic outbreaks, some of which diluted the quality of data collected. During group interviews, most parents were not entirely truthful about involving their children in child-labour activities. Although most respondents had an idea of what child labour is, their ignorance levels on the topic prevented them from stopping their children from working. The major findings of the research were that the cultural, social and economic setup of the community in the study area favoured child labour, although the child-labour legislation is against using children as labourers. Various ethnicities 6 in the study area considered a person between the ages of 5 and 12 years to be a child, yet the Constitution of Uganda dictates the age of childhood to be below 18 years. This causes conflict in the definition of who a child is. Although parents were aware of the Universal Primary Education (UPE) regulation penalties for not taking children to school, they still permitted children to engage in child-labour activities, and little has been done by government to curb the culprits. Awareness of the Sub Counties and Credit Co-operatives (SACCOs) and their implementation has not helped to reduce poverty in the area studied, resulting in an increased school dropout rate among school-going-age children, as well as more child-labour activities. The major conclusion of the study was that little has been done to increase the awareness levels of the teachers, parents and their children about child labour and its legislation, their knowledge of and involvement in micro-finance institutions in the community, and the availability of vocational training institutions. Little has therefore been done to reduce child-labour activities, improve the economic status of the community, and improve their human resource skills. The major recommendations of the research to the study are that culture should not override the Constitution as far as the definition of age limit is concerned. The government should carry out stakeholder analyses, and implement a life-skills and sensitisation programme in order to improve child participation in the Universal Primary Education (UPE) programme. Government should ensure that the society is given information about basic accounting, project planning and management skills, in order to be effectively involved in the economic programmes of SACCOs.
- Full Text:
- Date Issued: 2010
A critical analysis of discourses constructing portfolio assessment practices in three Eastern Cape schools
- Authors: Jones, Barbara Ellen
- Date: 2010
- Subjects: Discourse analysis -- South Africa -- Eastern Cape -- Case studies Competency-based education -- South Africa -- Eastern Cape -- Case studies Educational tests and measurements -- South Africa -- Eastern Cape -- Case studies Education -- Evaluation -- South Africa -- Eastern Cape -- Case studies Curriculum evaluation -- South Africa -- Eastern Cape -- Case studies
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1468 , http://hdl.handle.net/10962/d1003349
- Description: In 1998, South Africa introduced outcomes-based education to affect the shifts in pedagogy considered necessary following the move to democracy in 1994. Across the globe, the use of the portfolio to assess learners is increasingly being promoted as a form of progressive pedagogy. Hence, its adoption by the country as a new form of assessment practice was warranted. However, how the portfolio is constructed and perceived by educators within the classroom can become problematic in practice. This was apparent in the South African context and justifies research into how the portfolio is constructed as an assessment method in educational policy and by educators in the classrooms. The Curriculum Guide Directive text and the transcripts of twenty-one interviews carried out in three Eastern Cape schools served as the source of data for this study. Discourses make up a powerful framework of spoken, written and symbolic texts of institutional bureaucracies. Within these institutions human subjects are defined and constructed. Therefore, discourse construction acts as institutional forms of knowledge which can exude power over the individual if not made transparent. I used critical discourse analysis to uncover the discourses that were embedded within the Curriculum Guide Directive and to identify the discourses entrenched within the educators’ perceptions of the portfolio. The discourses in the Curriculum Guide Directive suggest the construction of the portfolio as a method of surveillance to track whether the educators are preparing learners for the school leaving examination and instructing the educators to provide evidence in the form of a portfolio. Analysis of the transcripts of the twenty one interviews with educators from three schools in the Eastern Cape indicated that the portfolio was not seen as a form of assessment by the educators, but as a form of discipline put in place by the Department of Education to ensure that they are preparing the learners for the school leaving examination and are able to produce proof of this preparation in the form of a portfolio. The discourses from the research highlighted that the school leaving examination is hegemonised into South African educational pedagogy as a form of traditional assessment and is not challenged even when it is no longer bringing about the dominant ideological goals. The portfolio was not seen as an assessment method by the educators nor represented as such in the Curriculum Guide Directive. Therefore, the job of the portfolio became that of a policing tool. Thus, a school curriculum which has been introduced with the intent of furthering social justice can become exclusive in practice, even with the best intentions.
- Full Text:
- Date Issued: 2010
- Authors: Jones, Barbara Ellen
- Date: 2010
- Subjects: Discourse analysis -- South Africa -- Eastern Cape -- Case studies Competency-based education -- South Africa -- Eastern Cape -- Case studies Educational tests and measurements -- South Africa -- Eastern Cape -- Case studies Education -- Evaluation -- South Africa -- Eastern Cape -- Case studies Curriculum evaluation -- South Africa -- Eastern Cape -- Case studies
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1468 , http://hdl.handle.net/10962/d1003349
- Description: In 1998, South Africa introduced outcomes-based education to affect the shifts in pedagogy considered necessary following the move to democracy in 1994. Across the globe, the use of the portfolio to assess learners is increasingly being promoted as a form of progressive pedagogy. Hence, its adoption by the country as a new form of assessment practice was warranted. However, how the portfolio is constructed and perceived by educators within the classroom can become problematic in practice. This was apparent in the South African context and justifies research into how the portfolio is constructed as an assessment method in educational policy and by educators in the classrooms. The Curriculum Guide Directive text and the transcripts of twenty-one interviews carried out in three Eastern Cape schools served as the source of data for this study. Discourses make up a powerful framework of spoken, written and symbolic texts of institutional bureaucracies. Within these institutions human subjects are defined and constructed. Therefore, discourse construction acts as institutional forms of knowledge which can exude power over the individual if not made transparent. I used critical discourse analysis to uncover the discourses that were embedded within the Curriculum Guide Directive and to identify the discourses entrenched within the educators’ perceptions of the portfolio. The discourses in the Curriculum Guide Directive suggest the construction of the portfolio as a method of surveillance to track whether the educators are preparing learners for the school leaving examination and instructing the educators to provide evidence in the form of a portfolio. Analysis of the transcripts of the twenty one interviews with educators from three schools in the Eastern Cape indicated that the portfolio was not seen as a form of assessment by the educators, but as a form of discipline put in place by the Department of Education to ensure that they are preparing the learners for the school leaving examination and are able to produce proof of this preparation in the form of a portfolio. The discourses from the research highlighted that the school leaving examination is hegemonised into South African educational pedagogy as a form of traditional assessment and is not challenged even when it is no longer bringing about the dominant ideological goals. The portfolio was not seen as an assessment method by the educators nor represented as such in the Curriculum Guide Directive. Therefore, the job of the portfolio became that of a policing tool. Thus, a school curriculum which has been introduced with the intent of furthering social justice can become exclusive in practice, even with the best intentions.
- Full Text:
- Date Issued: 2010
A model for the alignment of ICT education with business ICT skills requirements
- Authors: Calitz, André Paul
- Date: 2010
- Subjects: Educational technology -- South Africa , Education, Higher -- South Africa , Information technology -- Social aspects -- South Africa , Information technology -- Study and teaching
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8662 , http://hdl.handle.net/10948/1418 , Educational technology -- South Africa , Education, Higher -- South Africa , Information technology -- Social aspects -- South Africa , Information technology -- Study and teaching
- Description: The Information and Communications Technology (ICT) skills shortage is of national and international concern. Modern business practices require the implementation of new technologies supported by a workforce with current and diversified ICT skill-sets. Acquiring suitable ICT skills has become a difficult task and employers are seeing government intervention at all levels. The school system in South Africa is under increased pressure and is faced with continuously declining matriculation pass rates, specifically in subjects such as science and mathematics. Schools are experiencing a decline in the number of scholars (learners) enrolling for the Information Technology (IT) school curriculum. The IT curriculum at school level is being criticised; under-prepared teachers are blamed and lack of suitable facilities highlighted. Surveys conducted amongst grade 9 and grade 12 scholars in the Eastern Cape have shown that scholars are not considering careers in ICT. Teachers, career/guidance counsellors and parents contribute to scholars' career decisions and are not encouraging scholars to pursue careers in ICT. Tertiary institutions in South Africa and internationally, are experiencing a decline in student enrolments and in pass and throughput rates. Industry is holding tertiary institutions responsible for not providing the “correct” ICT graduate skill-sets and passing an insufficient number of quality ICT graduates desperately required by industry. The accreditation of computing degree programs, such as Computer Science (CS), Information Systems (IS) and Information Technology (IT), collectively referred to as CIT, offered by tertiary institutions is becoming an international requirement. The ICT industry is constantly changing and new job requirements and new career opportunities are frequently introduced. Graduates entering the ICT industry should have acquired knowledge about ICT career tracks in order to specialise and choose a suitable career path. Tertiary CIT degree programs should further be linked to specific career tracks and provide a multi-disciplined education to graduates. ii ICT graduates working in industry utilise skills obtained in under-graduate and post-graduate CIT degree programs. The ICT graduates have also obtained valuable skills working in industry, including business skills and soft skills. ICT skill surveys have identified the graduate skills gap, indicating ICT skills industry requires from graduates completing tertiary level qualifications. ICT graduates working in industry, for example indicated that programming in some cases is over-emphasised at school and tertiary level and that soft skills are ignored by tertiary institutions. An ICT Graduate Skills Classifications Framework is developed to address the graduate ICT skills gap and highlight important business skills, soft skills, technical skills and programming skills required by industry. In this thesis, an Industry ICT Value Chain Model is further developed that suggests a holistic approach to the problems experienced at all levels of ICT skills development, including government, industry, tertiary education institutions and at school level. Results from a number of research surveys conducted along the proposed Industry ICT Skills Value Chain Model indicated that problems exist at all stages in the value chain and that the problems can only be addressed involving government, industry and tertiary institutions collectively. A number of interventions is required and the support from industry is essential in achieving overall success in addressing the ICT skills shortage in South Africa. A proposed Industry ICT Skills Value Chain Model that can be utilised to address the ICT skills shortage in South Africa is presented.
- Full Text:
- Date Issued: 2010
- Authors: Calitz, André Paul
- Date: 2010
- Subjects: Educational technology -- South Africa , Education, Higher -- South Africa , Information technology -- Social aspects -- South Africa , Information technology -- Study and teaching
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8662 , http://hdl.handle.net/10948/1418 , Educational technology -- South Africa , Education, Higher -- South Africa , Information technology -- Social aspects -- South Africa , Information technology -- Study and teaching
- Description: The Information and Communications Technology (ICT) skills shortage is of national and international concern. Modern business practices require the implementation of new technologies supported by a workforce with current and diversified ICT skill-sets. Acquiring suitable ICT skills has become a difficult task and employers are seeing government intervention at all levels. The school system in South Africa is under increased pressure and is faced with continuously declining matriculation pass rates, specifically in subjects such as science and mathematics. Schools are experiencing a decline in the number of scholars (learners) enrolling for the Information Technology (IT) school curriculum. The IT curriculum at school level is being criticised; under-prepared teachers are blamed and lack of suitable facilities highlighted. Surveys conducted amongst grade 9 and grade 12 scholars in the Eastern Cape have shown that scholars are not considering careers in ICT. Teachers, career/guidance counsellors and parents contribute to scholars' career decisions and are not encouraging scholars to pursue careers in ICT. Tertiary institutions in South Africa and internationally, are experiencing a decline in student enrolments and in pass and throughput rates. Industry is holding tertiary institutions responsible for not providing the “correct” ICT graduate skill-sets and passing an insufficient number of quality ICT graduates desperately required by industry. The accreditation of computing degree programs, such as Computer Science (CS), Information Systems (IS) and Information Technology (IT), collectively referred to as CIT, offered by tertiary institutions is becoming an international requirement. The ICT industry is constantly changing and new job requirements and new career opportunities are frequently introduced. Graduates entering the ICT industry should have acquired knowledge about ICT career tracks in order to specialise and choose a suitable career path. Tertiary CIT degree programs should further be linked to specific career tracks and provide a multi-disciplined education to graduates. ii ICT graduates working in industry utilise skills obtained in under-graduate and post-graduate CIT degree programs. The ICT graduates have also obtained valuable skills working in industry, including business skills and soft skills. ICT skill surveys have identified the graduate skills gap, indicating ICT skills industry requires from graduates completing tertiary level qualifications. ICT graduates working in industry, for example indicated that programming in some cases is over-emphasised at school and tertiary level and that soft skills are ignored by tertiary institutions. An ICT Graduate Skills Classifications Framework is developed to address the graduate ICT skills gap and highlight important business skills, soft skills, technical skills and programming skills required by industry. In this thesis, an Industry ICT Value Chain Model is further developed that suggests a holistic approach to the problems experienced at all levels of ICT skills development, including government, industry, tertiary education institutions and at school level. Results from a number of research surveys conducted along the proposed Industry ICT Skills Value Chain Model indicated that problems exist at all stages in the value chain and that the problems can only be addressed involving government, industry and tertiary institutions collectively. A number of interventions is required and the support from industry is essential in achieving overall success in addressing the ICT skills shortage in South Africa. A proposed Industry ICT Skills Value Chain Model that can be utilised to address the ICT skills shortage in South Africa is presented.
- Full Text:
- Date Issued: 2010
A social realist analysis of collaborative curriculum development processes in an academic department at a South African university
- Authors: Vorster, Jo-Anne
- Date: 2010
- Subjects: Rhodes University -- Curricula Journalism -- Study and teaching -- South Africa -- Grahamstown Curriculum planning -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3339 , http://hdl.handle.net/10962/d1004314
- Description: This study reports on a social-realist analysis of collaborative curriculum development in a journalism and media studies (JMS) department at a South African university. Archer's social-realist meta-theoretical framework is used to theorise about mechanisms that influence collaborative curriculum development within the context of the JMS Department. The thesis examines the cultural, structural and agential conditions that influenced the process of developing a JMS curriculum that aimed to integrate theory and practice. Bernstein's theories of knowledge recontextualisation and disciplinary knowledge structures are used in the analysis. Bernstein argues that knowledge recontextualisation constitutes a site of struggle. This thesis is an examination of the "struggles" for the epistemic-pedagogic device (Maton's elaboration of Bernstein's epistemic device) during the recontextualisation process that aimed to integrate media studies (MS) and media production (MP) in the JMS curriculum. Traditionally academic work has been an individual endeavour. However, given the growing need to work in disciplinary and inter-disciplinary teams, it is imperative to develop knowledge of the mechanisms that influence such practices. This thesis is a contribution to knowledge of collaborative processes at the level of an academic department in a university. It contributes to knowledge of cultural, structural and agential mechanisms that enable or constrain collaborative curriculum development within a particular kind of context. In addition it contributes to knowledge of the nature of leadership that may be necessary to facilitate productive collaborative relationships and practices in such a context. The curriculum development project reported on in this thesis was initiated in 2003; however, data collection for the study was conducted in 2006 when the curriculum for the fourth year (JMS 4) of the Bachelor of Journalism degree was developed. Since the JMS course prepares students to work as journalists or media workers it is necessary for the curriculum and pedagogy to be oriented both towards the academy and towards the media industries. The aim of the JMS degree is to develop students who will be critically reflexive journalists or media workers. As such the course is both theoretical (MS) and practical (MP). One of the findings of this research project is that the integration of MS and MP is a complex project given that the knowledge of the two disciplines is structured differently. MS is concept-dependent and some aspects of it can be applied to journalism and media practice, while MP is practical and thus context-dependent, though underpinned by theory. A further finding is that both the collaborative work and the integration project required different identity shifts from the lecturers in the JMS Department. Some were more able to make the shifts than others. The thesis shows that the knowledge recontextualisation struggles in the curriculum development processes of the Department of JMS centred around, inter alia, the setting of boundaries between the department and the media and journalism industries, between MS and MP and between MS theory and journalism theory. In addition, existing boundaries between MS and MP lecturers had to be traversed. These boundaries were circumscribed by, amongst other things, unequal power relations emanating from the higher status traditionally accorded to theoretical knowledge by universities, the tensions around the nature of journalism education and training and the differential properties and powers of the various lecturers within the department. The existence of a strong regulative discourse was found to be an important unifying mechanism in a tension-ridden context.
- Full Text:
- Date Issued: 2010
- Authors: Vorster, Jo-Anne
- Date: 2010
- Subjects: Rhodes University -- Curricula Journalism -- Study and teaching -- South Africa -- Grahamstown Curriculum planning -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3339 , http://hdl.handle.net/10962/d1004314
- Description: This study reports on a social-realist analysis of collaborative curriculum development in a journalism and media studies (JMS) department at a South African university. Archer's social-realist meta-theoretical framework is used to theorise about mechanisms that influence collaborative curriculum development within the context of the JMS Department. The thesis examines the cultural, structural and agential conditions that influenced the process of developing a JMS curriculum that aimed to integrate theory and practice. Bernstein's theories of knowledge recontextualisation and disciplinary knowledge structures are used in the analysis. Bernstein argues that knowledge recontextualisation constitutes a site of struggle. This thesis is an examination of the "struggles" for the epistemic-pedagogic device (Maton's elaboration of Bernstein's epistemic device) during the recontextualisation process that aimed to integrate media studies (MS) and media production (MP) in the JMS curriculum. Traditionally academic work has been an individual endeavour. However, given the growing need to work in disciplinary and inter-disciplinary teams, it is imperative to develop knowledge of the mechanisms that influence such practices. This thesis is a contribution to knowledge of collaborative processes at the level of an academic department in a university. It contributes to knowledge of cultural, structural and agential mechanisms that enable or constrain collaborative curriculum development within a particular kind of context. In addition it contributes to knowledge of the nature of leadership that may be necessary to facilitate productive collaborative relationships and practices in such a context. The curriculum development project reported on in this thesis was initiated in 2003; however, data collection for the study was conducted in 2006 when the curriculum for the fourth year (JMS 4) of the Bachelor of Journalism degree was developed. Since the JMS course prepares students to work as journalists or media workers it is necessary for the curriculum and pedagogy to be oriented both towards the academy and towards the media industries. The aim of the JMS degree is to develop students who will be critically reflexive journalists or media workers. As such the course is both theoretical (MS) and practical (MP). One of the findings of this research project is that the integration of MS and MP is a complex project given that the knowledge of the two disciplines is structured differently. MS is concept-dependent and some aspects of it can be applied to journalism and media practice, while MP is practical and thus context-dependent, though underpinned by theory. A further finding is that both the collaborative work and the integration project required different identity shifts from the lecturers in the JMS Department. Some were more able to make the shifts than others. The thesis shows that the knowledge recontextualisation struggles in the curriculum development processes of the Department of JMS centred around, inter alia, the setting of boundaries between the department and the media and journalism industries, between MS and MP and between MS theory and journalism theory. In addition, existing boundaries between MS and MP lecturers had to be traversed. These boundaries were circumscribed by, amongst other things, unequal power relations emanating from the higher status traditionally accorded to theoretical knowledge by universities, the tensions around the nature of journalism education and training and the differential properties and powers of the various lecturers within the department. The existence of a strong regulative discourse was found to be an important unifying mechanism in a tension-ridden context.
- Full Text:
- Date Issued: 2010
A value-based approach to promoting excellence in mathematics education
- Authors: Austin, Pamela Winifred
- Date: 2010
- Subjects: Mathematics -- Study and teaching -- South Africa , Inquiry-based learning -- South Africa , Active learning -- South Africa , Effective teaching -- South Africa , Self-efficacy
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9482 , http://hdl.handle.net/10948/1656 , Mathematics -- Study and teaching -- South Africa , Inquiry-based learning -- South Africa , Active learning -- South Africa , Effective teaching -- South Africa , Self-efficacy
- Description: This research study has emerged as a result of my concern regarding the apparent low self-efficacy amongst initial teacher education students in my mathematics education classes. It also reflects a reported renewed interest in values, and the promotion of excellence in education. The effects of a values-based approach to mathematics education towards improving students’ self-efficacy and promoting excellence have been investigated, grounded within my ontology of excellence in mathematics education, which incorporates the values of respect, fairness, accountability, honesty and compassion. An inquiry-based teaching and learning approach formed the framework within which the study took place. Notions of ‘new scholarship’, premised on the view that teaching is about engagement in participatory learning, and the development of communities of creative students, provided the theoretical framework. Both quantitative and qualitative data gathering methods were used. Data-collection tools included affective-disposition statements, interviews, journal entries, as well as a video recording of a mathematics education lesson. The quantitative and qualitative data generated suggest improved levels of self-efficacy amongst the students who participated in the study. The data also suggest that a valuesbased approach to teaching can be used as an effective approach by mathematics teachers – and mathematics teacher educators – for the purpose of promoting the pursuit of excellence. As teacher education worldwide is currently characterised by a lack of vitality in teacher preparation (Grossman, 2008), the findings of this study should provide insights for teacher educators, teachers and policy makers who wish to promote mathematics self-efficacy, excellence and facilitate enhanced vitality within the teaching profession.
- Full Text:
- Date Issued: 2010
- Authors: Austin, Pamela Winifred
- Date: 2010
- Subjects: Mathematics -- Study and teaching -- South Africa , Inquiry-based learning -- South Africa , Active learning -- South Africa , Effective teaching -- South Africa , Self-efficacy
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9482 , http://hdl.handle.net/10948/1656 , Mathematics -- Study and teaching -- South Africa , Inquiry-based learning -- South Africa , Active learning -- South Africa , Effective teaching -- South Africa , Self-efficacy
- Description: This research study has emerged as a result of my concern regarding the apparent low self-efficacy amongst initial teacher education students in my mathematics education classes. It also reflects a reported renewed interest in values, and the promotion of excellence in education. The effects of a values-based approach to mathematics education towards improving students’ self-efficacy and promoting excellence have been investigated, grounded within my ontology of excellence in mathematics education, which incorporates the values of respect, fairness, accountability, honesty and compassion. An inquiry-based teaching and learning approach formed the framework within which the study took place. Notions of ‘new scholarship’, premised on the view that teaching is about engagement in participatory learning, and the development of communities of creative students, provided the theoretical framework. Both quantitative and qualitative data gathering methods were used. Data-collection tools included affective-disposition statements, interviews, journal entries, as well as a video recording of a mathematics education lesson. The quantitative and qualitative data generated suggest improved levels of self-efficacy amongst the students who participated in the study. The data also suggest that a valuesbased approach to teaching can be used as an effective approach by mathematics teachers – and mathematics teacher educators – for the purpose of promoting the pursuit of excellence. As teacher education worldwide is currently characterised by a lack of vitality in teacher preparation (Grossman, 2008), the findings of this study should provide insights for teacher educators, teachers and policy makers who wish to promote mathematics self-efficacy, excellence and facilitate enhanced vitality within the teaching profession.
- Full Text:
- Date Issued: 2010
Aerial optical fibres in telecommunication systems : SOP and PMD monitoring, and tolerance of modulation formats
- Authors: Ireeta, Winston Tumps
- Date: 2010
- Subjects: Optical communications , Fiber optics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10542 , http://hdl.handle.net/10948/1478 , http://hdl.handle.net/10948/d1012894 , Optical communications , Fiber optics
- Description: The topic of this thesis is aerial optical fibres in telecommunication systems: state of polarization (SOP) and polarization mode dispersion (PMD) monitoring and tolerance of modulation formats. Errors in optical fibre telecommunication systems are introduced when these polarization effects (SOP and PMD) change. These changes are so intense especially in aerial optical fibres. Part of the backbone of South Africa’s national grid includes long distances of aerial optical fibre between transmission exchange stations. The work in this thesis can be divided into three parts which all deal with the major aspects of PMD in deployed aerial optical fibres: characterization, environmental effects plus other perturbations, and tolerance of different modulation formats. In our work, SOP and PMD field measurements revealed that they both fluctuate more rapidly in deployed aerial optical fibres especially on windy and hot days. The SOP and PMD changes in the aerial optical fibres showed a significant correlation with these environmental parameters. SOP and PMD are stochastic in nature due to changes in the properties of the optical fibres and its positions because of both intrinsic and extrinsic perturbations. In our work, with only 184 PMD values measured and obtained by use of the FTB-5700 single-ended dispersion analyzer, the predicted theoretical Gaussian fit was obtained with a mean of 0.47 ps and standard deviation of 0.08 ps. This small standard deviation was justification for its robustness and accuracy. The statistical distributions for first-order polarization mode dispersion (FO-PMD) and second-order polarization mode dispersion (SO-PMD) for the first time were experimentally confirmed when measured using the FTB-5700 single-ended dispersion analyzer instrument for deployed aerial optical fibres. We were also able to determine the time scale over which to compensate FO-PMD in deployed aerial fibres using the directional time drift autocorrelation function method. It is slightly higher than 390 s for SOP measurements made on a particular windy and hot day. This is due to the fact that the changes of the PMD vector are known to be slower than the SOP changes. vi We also investigated the theoretical statistical distribution that corresponds to output SOP variations. The SOP variations can either be with wavelength (for buried fibre) or with time (for aerial fibre). Our results showed that the statistics of the relative SOP changes approached the distribution proposed by Foschini et al. (2000). Advanced optical modulation formats have become a key ingredient in the design of modern state-of-the-art wavelength-division-multiplexed (WDM) optical transmission systems. In our work, we investigated which of these advanced modulation formats is best suited for the South African network especially on systems that have links of aerial optical fibres. Keywords: aerial optical fibre, polarization mode dispersion (PMD), principal states of polarization (PSP), state of polarization (SOP), first-order PMD, second-order PMD.
- Full Text:
- Date Issued: 2010
- Authors: Ireeta, Winston Tumps
- Date: 2010
- Subjects: Optical communications , Fiber optics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10542 , http://hdl.handle.net/10948/1478 , http://hdl.handle.net/10948/d1012894 , Optical communications , Fiber optics
- Description: The topic of this thesis is aerial optical fibres in telecommunication systems: state of polarization (SOP) and polarization mode dispersion (PMD) monitoring and tolerance of modulation formats. Errors in optical fibre telecommunication systems are introduced when these polarization effects (SOP and PMD) change. These changes are so intense especially in aerial optical fibres. Part of the backbone of South Africa’s national grid includes long distances of aerial optical fibre between transmission exchange stations. The work in this thesis can be divided into three parts which all deal with the major aspects of PMD in deployed aerial optical fibres: characterization, environmental effects plus other perturbations, and tolerance of different modulation formats. In our work, SOP and PMD field measurements revealed that they both fluctuate more rapidly in deployed aerial optical fibres especially on windy and hot days. The SOP and PMD changes in the aerial optical fibres showed a significant correlation with these environmental parameters. SOP and PMD are stochastic in nature due to changes in the properties of the optical fibres and its positions because of both intrinsic and extrinsic perturbations. In our work, with only 184 PMD values measured and obtained by use of the FTB-5700 single-ended dispersion analyzer, the predicted theoretical Gaussian fit was obtained with a mean of 0.47 ps and standard deviation of 0.08 ps. This small standard deviation was justification for its robustness and accuracy. The statistical distributions for first-order polarization mode dispersion (FO-PMD) and second-order polarization mode dispersion (SO-PMD) for the first time were experimentally confirmed when measured using the FTB-5700 single-ended dispersion analyzer instrument for deployed aerial optical fibres. We were also able to determine the time scale over which to compensate FO-PMD in deployed aerial fibres using the directional time drift autocorrelation function method. It is slightly higher than 390 s for SOP measurements made on a particular windy and hot day. This is due to the fact that the changes of the PMD vector are known to be slower than the SOP changes. vi We also investigated the theoretical statistical distribution that corresponds to output SOP variations. The SOP variations can either be with wavelength (for buried fibre) or with time (for aerial fibre). Our results showed that the statistics of the relative SOP changes approached the distribution proposed by Foschini et al. (2000). Advanced optical modulation formats have become a key ingredient in the design of modern state-of-the-art wavelength-division-multiplexed (WDM) optical transmission systems. In our work, we investigated which of these advanced modulation formats is best suited for the South African network especially on systems that have links of aerial optical fibres. Keywords: aerial optical fibre, polarization mode dispersion (PMD), principal states of polarization (PSP), state of polarization (SOP), first-order PMD, second-order PMD.
- Full Text:
- Date Issued: 2010
An analysis of emerging forms of social organisation and agency in the aftermath of 'fast track' land reform in Zimbabwe
- Authors: Murisa, Tendai
- Date: 2010
- Subjects: Land reform -- Zimbabwe Right of property -- Zimbabwe Zimbabwe -- Economic conditions Zimbabwe -- Social conditions -- 1980- Zimbabwe -- Politics and government -- 1980- Zimbabwe -- Social life and customs Land settlement -- Social aspects -- Zimbabwe Group identity -- Zimbabwe Social change -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3293 , http://hdl.handle.net/10962/d1003081
- Description: The fast track land reform programme resulted in a fundamental reorganisation of rural relations in Zimbabwe, changing the landscape in an irreversible way with people from diverse backgrounds converging on former white-owned farms. This thesis tells the story of how the newly resettled land beneficiaries are organising themselves socially in response to various economic challenges. It makes a contribution towards understanding how redistributive land reforms and local government restructuring influence rural social organisation and agency. Furthermore the study examines local perceptions on the meanings of the „farm‟ and „land redistribution‟. An utterance by one war veteran “what used to be your farm is now our land and you are free to take your farm but leave our land” provides an alternative rendition to contestations of restitution versus a purely farm productionist discourse. The study, through an analysis of primary and secondary data, provides a fresh understanding of the social outcomes of fast track. It traces the evolution of land and agrarian reforms in post-independence Zimbabwe and the political and social economic context that led to „fast track‟. Through an analysis of field findings the thesis is able to define the dominant social groups that were resettled during fast track and the challenges they face in utilising the land. The findings show that the majority of the land beneficiaries were from the customary areas, with limited agricultural experiences. Local cooperation within informal networks and local farmer groups has been identified as one of the ways in which social reproduction is being organised. These groups are responsible for enhancing production capacity but they face a number of constraints. The study derives its theoretical foundation from the post 1980s debates on rural society dominated by Mafeje (1993, 2003), Rahmato (1991) and Mamdani (1996). The debates centred on how institutions of inclusion, authority and cooperation such as the lineage groups, local farmer groups and traditional authority remain relevant in the organisation of post-independent rural African society especially in a context of increased commoditisation of rural relations of production. Using theoretical insights derived from analysing the role of the lineage groups in the allocation of critical resources such as land and the influence of traditional authority (indirect rule) as a form of local government, the study examines how social organisation is emerging in areas where neither lineage nor traditional authority are not dominant. The thesis of rural cooperation through local groups as advanced by Rahmato (1991) and Moyo (2002) provides partial insights into the response mechanisms that land beneficiaries invoke in this instance. It is not necessarily an autonomous space of organisation but rather the state is actively involved through various functionaries including extension officers who invariably advance a very productionist approach. The state‟s monopoly through its local functionaries hides its political cooptation effect by emphasising organisation for production without questioning the manner in which that production is externally controlled through limited rights over land, the state‟s monopoly over inputs supply and markets for commodities. Whilst land reform has been driven by local participation through land occupations, local government reform has been technocratically determined through Ministerial directives. There is however little innovation in the form of local government that is being introduced. It expands the fusion of authority between elected Rural District Councils and unelected traditional authority functionaries. The forms of social organisation and agency that have emerged remain subordinated to the state with no links to other networks of rural producers‟ associations and urban civil society organisations. These developments form part of a longheld tradition within the Zimbabwean state where the legitimacy of local organisation and authority is usurped to service the interests of the state. Thus whilst land reform has to a certain extent accommodated the majority poor, the ensuing local government and agrarian reforms are more focused on limiting their participation in broader processes of political engagement around distribution and accumulation and their own governance.
- Full Text:
- Date Issued: 2010
- Authors: Murisa, Tendai
- Date: 2010
- Subjects: Land reform -- Zimbabwe Right of property -- Zimbabwe Zimbabwe -- Economic conditions Zimbabwe -- Social conditions -- 1980- Zimbabwe -- Politics and government -- 1980- Zimbabwe -- Social life and customs Land settlement -- Social aspects -- Zimbabwe Group identity -- Zimbabwe Social change -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3293 , http://hdl.handle.net/10962/d1003081
- Description: The fast track land reform programme resulted in a fundamental reorganisation of rural relations in Zimbabwe, changing the landscape in an irreversible way with people from diverse backgrounds converging on former white-owned farms. This thesis tells the story of how the newly resettled land beneficiaries are organising themselves socially in response to various economic challenges. It makes a contribution towards understanding how redistributive land reforms and local government restructuring influence rural social organisation and agency. Furthermore the study examines local perceptions on the meanings of the „farm‟ and „land redistribution‟. An utterance by one war veteran “what used to be your farm is now our land and you are free to take your farm but leave our land” provides an alternative rendition to contestations of restitution versus a purely farm productionist discourse. The study, through an analysis of primary and secondary data, provides a fresh understanding of the social outcomes of fast track. It traces the evolution of land and agrarian reforms in post-independence Zimbabwe and the political and social economic context that led to „fast track‟. Through an analysis of field findings the thesis is able to define the dominant social groups that were resettled during fast track and the challenges they face in utilising the land. The findings show that the majority of the land beneficiaries were from the customary areas, with limited agricultural experiences. Local cooperation within informal networks and local farmer groups has been identified as one of the ways in which social reproduction is being organised. These groups are responsible for enhancing production capacity but they face a number of constraints. The study derives its theoretical foundation from the post 1980s debates on rural society dominated by Mafeje (1993, 2003), Rahmato (1991) and Mamdani (1996). The debates centred on how institutions of inclusion, authority and cooperation such as the lineage groups, local farmer groups and traditional authority remain relevant in the organisation of post-independent rural African society especially in a context of increased commoditisation of rural relations of production. Using theoretical insights derived from analysing the role of the lineage groups in the allocation of critical resources such as land and the influence of traditional authority (indirect rule) as a form of local government, the study examines how social organisation is emerging in areas where neither lineage nor traditional authority are not dominant. The thesis of rural cooperation through local groups as advanced by Rahmato (1991) and Moyo (2002) provides partial insights into the response mechanisms that land beneficiaries invoke in this instance. It is not necessarily an autonomous space of organisation but rather the state is actively involved through various functionaries including extension officers who invariably advance a very productionist approach. The state‟s monopoly through its local functionaries hides its political cooptation effect by emphasising organisation for production without questioning the manner in which that production is externally controlled through limited rights over land, the state‟s monopoly over inputs supply and markets for commodities. Whilst land reform has been driven by local participation through land occupations, local government reform has been technocratically determined through Ministerial directives. There is however little innovation in the form of local government that is being introduced. It expands the fusion of authority between elected Rural District Councils and unelected traditional authority functionaries. The forms of social organisation and agency that have emerged remain subordinated to the state with no links to other networks of rural producers‟ associations and urban civil society organisations. These developments form part of a longheld tradition within the Zimbabwean state where the legitimacy of local organisation and authority is usurped to service the interests of the state. Thus whilst land reform has to a certain extent accommodated the majority poor, the ensuing local government and agrarian reforms are more focused on limiting their participation in broader processes of political engagement around distribution and accumulation and their own governance.
- Full Text:
- Date Issued: 2010
An empirical phenomenological investigation of procrastinating behaviour
- Authors: Barratt, Neal Anthony
- Date: 2010
- Subjects: Procrastination Self-actualization (Psychology) Cognitive psychology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2929 , http://hdl.handle.net/10962/d1002438
- Description: A qualitative empirical phenomenological study was undertaken to determine the self-experience of procrastinating behaviour. Five students each gave an account of an occasion when they procrastinated. The resultant protocols were analysed and the Situated Structure of each individual’s experience was reported. From these, the General Structure of procrastinating behaviour was determined. A further, novel step was added to the standard methodology, whereby ‘themes’ were extracted from participant protocols and a ‘Composite Reality’ of everyday-life procrastination was rendered. Participants’ accounts suggest they are concerned the results of intellectual tasks they undertake will be seen as equivalent to their quality of being-as-an-individual: poor work results will be interpreted by important-others as evidence of participants’ poor quality of self – which is to be avoided. This study suggests that procrastination is a ploy used by individuals to avoid criticism, by deflecting assessment of their capacity to complete a task well, to instead, what they are capable of when only a limited time is available. Conclusions drawn by the important-others of participants’ true ability are thereby confounded. The results achieved in the phenomenological study were compared with others originating from various quantitative studies, and considerable overlap was found. The experiential richness of the phenomenological results point to a worthwhile methodological strategy for future procrastination research.
- Full Text:
- Date Issued: 2010
- Authors: Barratt, Neal Anthony
- Date: 2010
- Subjects: Procrastination Self-actualization (Psychology) Cognitive psychology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2929 , http://hdl.handle.net/10962/d1002438
- Description: A qualitative empirical phenomenological study was undertaken to determine the self-experience of procrastinating behaviour. Five students each gave an account of an occasion when they procrastinated. The resultant protocols were analysed and the Situated Structure of each individual’s experience was reported. From these, the General Structure of procrastinating behaviour was determined. A further, novel step was added to the standard methodology, whereby ‘themes’ were extracted from participant protocols and a ‘Composite Reality’ of everyday-life procrastination was rendered. Participants’ accounts suggest they are concerned the results of intellectual tasks they undertake will be seen as equivalent to their quality of being-as-an-individual: poor work results will be interpreted by important-others as evidence of participants’ poor quality of self – which is to be avoided. This study suggests that procrastination is a ploy used by individuals to avoid criticism, by deflecting assessment of their capacity to complete a task well, to instead, what they are capable of when only a limited time is available. Conclusions drawn by the important-others of participants’ true ability are thereby confounded. The results achieved in the phenomenological study were compared with others originating from various quantitative studies, and considerable overlap was found. The experiential richness of the phenomenological results point to a worthwhile methodological strategy for future procrastination research.
- Full Text:
- Date Issued: 2010
An evaluation of leadership characteristics required to meet the demands of a strategic change process in the automative cluster in the Eastern Cape region
- Authors: Angloher, Sanette
- Date: 2010
- Subjects: Leadership , Organizational change
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:9341 , http://hdl.handle.net/10948/1261 , Leadership , Organizational change
- Description: Against a backdrop of increasing globalisation, deregulation, the rapid pace of technological innovation, a growing knowledge workforce, and shifting social and demographic trends, the primary task of management today is the leadership of organisational change (Graetz, 2000:550). In the words of Lussier and Achua Abstract v (2001:9): “The companies that will survive in the new global competitiveness environment are those that can attract and maintain leaders”. The above emphasises the important role of managers during times when change take place in the organisation. Yet employees are often managed inappropriately in a period of change. There are two reasons for this: (1) managers managing change are under pressure which undermines their own performance, (2) organisations often do not possess managers who are skilful at handling change. It is this second reason that will form the focus of this study. Carnall (1999:105) states that managing change effectively requires an understanding of both what is and seems likely to happen and of how people react to change, and a skilful management performance. Leaders must take on more facilitative roles, as competencies in change management become critical to creating and sustaining effective organisations. The major technological advances of today rely heavily on leaders to facilitate change. Leaders need to encourage people to “collaborate, take risks, take responsibility and be accountable for the change process the organisation must continually undergo to maintain a leadership position in its industry”, according to Moran and Brightman (2000:3). They furthermore argue that “change leaders recognise that they are always trying to balance stability and change. It is a delicate balance to accomplish since employees desire order and stability, while organisations must be ready to adapt to changing conditions quickly”. In this rapidly changing world, organisations must become more flexible, more responsive, and more willing to change and adapt. They must create and assimilate new knowledge at an increasing pace, encourage innovation, and learn to compete in new ways. Dess and Picken (2000:30) argue that the leaders of these organisations must be proactive in facilitating organisational learning and encouraging positive adaptation to external changes. The above shows what an important role leaders/managers have to play in the strategic change process. They need to possess the requisite skills in leadership, problem solving, continuous improvement, team effectiveness, and customer service in order to ensure the long-term growth and stability in the organisation which change can bring about. This research project will identify the various skills needed to successfully manage a change initiative.
- Full Text:
- Date Issued: 2010
- Authors: Angloher, Sanette
- Date: 2010
- Subjects: Leadership , Organizational change
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:9341 , http://hdl.handle.net/10948/1261 , Leadership , Organizational change
- Description: Against a backdrop of increasing globalisation, deregulation, the rapid pace of technological innovation, a growing knowledge workforce, and shifting social and demographic trends, the primary task of management today is the leadership of organisational change (Graetz, 2000:550). In the words of Lussier and Achua Abstract v (2001:9): “The companies that will survive in the new global competitiveness environment are those that can attract and maintain leaders”. The above emphasises the important role of managers during times when change take place in the organisation. Yet employees are often managed inappropriately in a period of change. There are two reasons for this: (1) managers managing change are under pressure which undermines their own performance, (2) organisations often do not possess managers who are skilful at handling change. It is this second reason that will form the focus of this study. Carnall (1999:105) states that managing change effectively requires an understanding of both what is and seems likely to happen and of how people react to change, and a skilful management performance. Leaders must take on more facilitative roles, as competencies in change management become critical to creating and sustaining effective organisations. The major technological advances of today rely heavily on leaders to facilitate change. Leaders need to encourage people to “collaborate, take risks, take responsibility and be accountable for the change process the organisation must continually undergo to maintain a leadership position in its industry”, according to Moran and Brightman (2000:3). They furthermore argue that “change leaders recognise that they are always trying to balance stability and change. It is a delicate balance to accomplish since employees desire order and stability, while organisations must be ready to adapt to changing conditions quickly”. In this rapidly changing world, organisations must become more flexible, more responsive, and more willing to change and adapt. They must create and assimilate new knowledge at an increasing pace, encourage innovation, and learn to compete in new ways. Dess and Picken (2000:30) argue that the leaders of these organisations must be proactive in facilitating organisational learning and encouraging positive adaptation to external changes. The above shows what an important role leaders/managers have to play in the strategic change process. They need to possess the requisite skills in leadership, problem solving, continuous improvement, team effectiveness, and customer service in order to ensure the long-term growth and stability in the organisation which change can bring about. This research project will identify the various skills needed to successfully manage a change initiative.
- Full Text:
- Date Issued: 2010
An evaluation of the BAE/SAAB South African Royal Manufacturing project in Virginia, Free State Province : a case study of the implementation of the South African Defence Offsets
- Authors: Wellmann, Gwendolyn
- Date: 2010
- Subjects: Arms transfers -- South Africa , Weapons industry -- South Africa , South Africa -- Military relations
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9075 , http://hdl.handle.net/10948/1296 , Arms transfers -- South Africa , Weapons industry -- South Africa , South Africa -- Military relations
- Description: This study is an evaluation of the BAE Systems/SAAB consortium National Industrial Programme project, South African Royal Manufacturers (SARM), which forms part of BAE Systems/SAAB’s National Industrial Participation Programme (NIPP) obligations resulting from their participation in South Africa’s 1998 Strategic Procurement Programme (popularly referred to as the ‘arms deal’). SARM was a gold chain manufacturing plant, located in the Free State mining town of Virginia and which was implemented by the BAE Systems/SAAB consortium in partnership with the Harmony Gold Mining Company. Funding for the business was provided by the BAE Systems/SAAB consortium as part of their industrial participation obligation. This funding was supplemented with a loan obtained from the South African Industrial Development Corporation (IDC) to the value of 40% of the cash funds; while land and buildings, as well as loans in the form of gold granules and bars, were provided by Harmony Gold Company, as part of what they describe as their corporate social responsibility towards the Virginia area where they are the only mining company operating; and also simultaneously as their obligation towards gold beneficiation as required by law. The business failed after less than 12 months of operation amidst allegations of theft of gold and the sudden lay-off of approximately 500 poor black rural women. The company’s liquidation appears to be on the backburner indefinitely. The study was conducted over a period of 18 months, and this thesis written over several more. As part of this evaluation several issues were investigated. These issues are: the push for beneficiation of South African mined metals; the National Industrial Participation Programme; local government development; the BAE Systems/SAAB consortium and other similar companies which are involved in jewellery production for export as part of both the country’s beneficiation drive, as well as the 3 NIPP. These other companies are used in this study as a ‘control’ group against which SARM’s performance can be measured realistically. Different research methods were used during the evaluation, including secondary document reviews, face-to-face and telephonic interviews with key-informants, the use of e-mail to contact key-informants, as well as conducting face-to-face questionnaires with random interviewees, and a focus group discussion with SARM ex-workers. There were several limitations to this study. The primary limitation was the inaccessibility of official and legal documents pertaining to both SARM, and the 1998 arms deal. SARM no longer exists, and thus the evaluation results should be used as lessons learned for similar projects in the future.
- Full Text:
- Date Issued: 2010
- Authors: Wellmann, Gwendolyn
- Date: 2010
- Subjects: Arms transfers -- South Africa , Weapons industry -- South Africa , South Africa -- Military relations
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9075 , http://hdl.handle.net/10948/1296 , Arms transfers -- South Africa , Weapons industry -- South Africa , South Africa -- Military relations
- Description: This study is an evaluation of the BAE Systems/SAAB consortium National Industrial Programme project, South African Royal Manufacturers (SARM), which forms part of BAE Systems/SAAB’s National Industrial Participation Programme (NIPP) obligations resulting from their participation in South Africa’s 1998 Strategic Procurement Programme (popularly referred to as the ‘arms deal’). SARM was a gold chain manufacturing plant, located in the Free State mining town of Virginia and which was implemented by the BAE Systems/SAAB consortium in partnership with the Harmony Gold Mining Company. Funding for the business was provided by the BAE Systems/SAAB consortium as part of their industrial participation obligation. This funding was supplemented with a loan obtained from the South African Industrial Development Corporation (IDC) to the value of 40% of the cash funds; while land and buildings, as well as loans in the form of gold granules and bars, were provided by Harmony Gold Company, as part of what they describe as their corporate social responsibility towards the Virginia area where they are the only mining company operating; and also simultaneously as their obligation towards gold beneficiation as required by law. The business failed after less than 12 months of operation amidst allegations of theft of gold and the sudden lay-off of approximately 500 poor black rural women. The company’s liquidation appears to be on the backburner indefinitely. The study was conducted over a period of 18 months, and this thesis written over several more. As part of this evaluation several issues were investigated. These issues are: the push for beneficiation of South African mined metals; the National Industrial Participation Programme; local government development; the BAE Systems/SAAB consortium and other similar companies which are involved in jewellery production for export as part of both the country’s beneficiation drive, as well as the 3 NIPP. These other companies are used in this study as a ‘control’ group against which SARM’s performance can be measured realistically. Different research methods were used during the evaluation, including secondary document reviews, face-to-face and telephonic interviews with key-informants, the use of e-mail to contact key-informants, as well as conducting face-to-face questionnaires with random interviewees, and a focus group discussion with SARM ex-workers. There were several limitations to this study. The primary limitation was the inaccessibility of official and legal documents pertaining to both SARM, and the 1998 arms deal. SARM no longer exists, and thus the evaluation results should be used as lessons learned for similar projects in the future.
- Full Text:
- Date Issued: 2010
An intergrated learning programme for the Knysna Montessori school
- Authors: Nel, Andri
- Date: 2010
- Subjects: Education -- South Africa Curricula , Competency-based education -- South Africa , Education, Primary -- South Africa
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:9443 , http://hdl.handle.net/10948/1142 , Education -- South Africa Curricula , Competency-based education -- South Africa , Education, Primary -- South Africa
- Description: In line with Montessori methodology, the Knysna Montessori School runs its programmes in an integrated and holistic manner. Learning programmes are based on a blend of various Montessori learning programmes and the Revised National Curriculum Statement (RNCS). Classes are divided into three year-age groupings; and integrated learning programmes are in place within the pre-school, (including grade R), the grade 1 to 3 class, and the grade 4 to 6 class. However, the grade 7 to 9 Montessori class has been running in a more traditional and less integrated manner since its inception in 2004. That has motivated the undertaking of this study. The main aim of this qualitative study has been to determine how to best arrange the RNCS according to Montessori principles, that is to say, in a holistic and integrated manner, with the intention of presenting a learning programme for the grade 7 to 9 class. This aim was based on a constructivist philosophical foundation and addressed in conjunction with interpretivism and critical theory. The grounded theory research paradigm was followed. In this paradigm research findings are grounded in the data gathering and the analysis. Three methods of data collection were applied, namely a literature review, interviews and document analysis. A literature review was conducted to gain a better overview and understanding of the RNCS and Outcomes-Based Education (OBE). Furthermore, through the literature review, an in-depth understanding of the Montessori method of education, adolescent development and integrated and holistic education have been achieved. Interviews were conducted with staff from the Knysna Montessori School, with the purpose of gathering information on the Knysna Montessori School and its current application to the RNCS, from pre-school to grade 6. An availability and purposive sampling method was applied, in order to determine which staff members to interview. Finally, document analysis was done. The learning areas for the senior phase (grades 7 to 9) of the General Education and Training Band (GET) of the RNCS were coded and analysed in order to discover emergent themes within the RNCS and how these link with the Montessori curriculum arrangement for this age group. It became apparent that Montessori classrooms, both prior to and for the senior phase, are divided into three areas, namely language, mathematics and cultural studies. Based on this knowledge, as well as the documentary analysis, an integrated learning programme, grounded in the data analysis, was designed. It was found that the RNCS matches well with Montessori’s curriculum arrangement. Thus, this learning programme is in line with Montessori’s curriculum arrangement for the senior phase of the GET band. Such a curriculum arrangement integrates the learning outcomes and assessment standards from arts and culture, economic and management sciences, life orientation, natural sciences, social sciences and technology into different studies. These are globally referred to as cultural studies. However, specific attention was also given to moral education, self-expression through music, art and drama, entrepreneurship, career education and sport. The conclusion was reached that an integrated learning programme, based on Montessori principles and in line with the RNCS requirement, is possible for the Knysna Montessori School.
- Full Text:
- Date Issued: 2010
- Authors: Nel, Andri
- Date: 2010
- Subjects: Education -- South Africa Curricula , Competency-based education -- South Africa , Education, Primary -- South Africa
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:9443 , http://hdl.handle.net/10948/1142 , Education -- South Africa Curricula , Competency-based education -- South Africa , Education, Primary -- South Africa
- Description: In line with Montessori methodology, the Knysna Montessori School runs its programmes in an integrated and holistic manner. Learning programmes are based on a blend of various Montessori learning programmes and the Revised National Curriculum Statement (RNCS). Classes are divided into three year-age groupings; and integrated learning programmes are in place within the pre-school, (including grade R), the grade 1 to 3 class, and the grade 4 to 6 class. However, the grade 7 to 9 Montessori class has been running in a more traditional and less integrated manner since its inception in 2004. That has motivated the undertaking of this study. The main aim of this qualitative study has been to determine how to best arrange the RNCS according to Montessori principles, that is to say, in a holistic and integrated manner, with the intention of presenting a learning programme for the grade 7 to 9 class. This aim was based on a constructivist philosophical foundation and addressed in conjunction with interpretivism and critical theory. The grounded theory research paradigm was followed. In this paradigm research findings are grounded in the data gathering and the analysis. Three methods of data collection were applied, namely a literature review, interviews and document analysis. A literature review was conducted to gain a better overview and understanding of the RNCS and Outcomes-Based Education (OBE). Furthermore, through the literature review, an in-depth understanding of the Montessori method of education, adolescent development and integrated and holistic education have been achieved. Interviews were conducted with staff from the Knysna Montessori School, with the purpose of gathering information on the Knysna Montessori School and its current application to the RNCS, from pre-school to grade 6. An availability and purposive sampling method was applied, in order to determine which staff members to interview. Finally, document analysis was done. The learning areas for the senior phase (grades 7 to 9) of the General Education and Training Band (GET) of the RNCS were coded and analysed in order to discover emergent themes within the RNCS and how these link with the Montessori curriculum arrangement for this age group. It became apparent that Montessori classrooms, both prior to and for the senior phase, are divided into three areas, namely language, mathematics and cultural studies. Based on this knowledge, as well as the documentary analysis, an integrated learning programme, grounded in the data analysis, was designed. It was found that the RNCS matches well with Montessori’s curriculum arrangement. Thus, this learning programme is in line with Montessori’s curriculum arrangement for the senior phase of the GET band. Such a curriculum arrangement integrates the learning outcomes and assessment standards from arts and culture, economic and management sciences, life orientation, natural sciences, social sciences and technology into different studies. These are globally referred to as cultural studies. However, specific attention was also given to moral education, self-expression through music, art and drama, entrepreneurship, career education and sport. The conclusion was reached that an integrated learning programme, based on Montessori principles and in line with the RNCS requirement, is possible for the Knysna Montessori School.
- Full Text:
- Date Issued: 2010
An investigation into implementation of language policy in the Eastern Cape with specific reference to isiXhosa
- Authors: Made, Zoliswa Jacqueline
- Date: 2010
- Subjects: Language policy -- South Africa -- Eastern Cape , Language Planning -- South Africa -- Eastern Cape , Xhosa language -- South Africa -- Eastern Cape , Language and education -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DLitt
- Identifier: vital:8456 , http://hdl.handle.net/10948/1181 , Language policy -- South Africa -- Eastern Cape , Language Planning -- South Africa -- Eastern Cape , Xhosa language -- South Africa -- Eastern Cape , Language and education -- South Africa -- Eastern Cape
- Description: This study is about An Investigation into Implementation of Language Policy in the Eastern Cape with specific reference to isiXhosa. The objectives of this study are to investigate the current state of language policy implementation plan in local government sectors and schools and to propose a strategy for a sustainable language implementation plan for indigenous languages of South Africa. Chapter 1 provides the background, definitions of terms, the statement of the problem, the research methods used and the literature reviewed. Chapter 2 deals with the critical analysis of language policy, looking at the types of language policies and various relevant language policies. Chapter 3 addresses challenges facing the indigenous languages of South Africa (with specific reference to isiXhosa) especially at provincial level. Chapter 4 discusses the implementation strategies which will help in the development of the indigenous languages. Chapter 5 concludes the study by presenting findings and recommendations for future research.
- Full Text:
- Date Issued: 2010
- Authors: Made, Zoliswa Jacqueline
- Date: 2010
- Subjects: Language policy -- South Africa -- Eastern Cape , Language Planning -- South Africa -- Eastern Cape , Xhosa language -- South Africa -- Eastern Cape , Language and education -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DLitt
- Identifier: vital:8456 , http://hdl.handle.net/10948/1181 , Language policy -- South Africa -- Eastern Cape , Language Planning -- South Africa -- Eastern Cape , Xhosa language -- South Africa -- Eastern Cape , Language and education -- South Africa -- Eastern Cape
- Description: This study is about An Investigation into Implementation of Language Policy in the Eastern Cape with specific reference to isiXhosa. The objectives of this study are to investigate the current state of language policy implementation plan in local government sectors and schools and to propose a strategy for a sustainable language implementation plan for indigenous languages of South Africa. Chapter 1 provides the background, definitions of terms, the statement of the problem, the research methods used and the literature reviewed. Chapter 2 deals with the critical analysis of language policy, looking at the types of language policies and various relevant language policies. Chapter 3 addresses challenges facing the indigenous languages of South Africa (with specific reference to isiXhosa) especially at provincial level. Chapter 4 discusses the implementation strategies which will help in the development of the indigenous languages. Chapter 5 concludes the study by presenting findings and recommendations for future research.
- Full Text:
- Date Issued: 2010
An investigation into the feasibility of incorporating didanosine into innovative solid lipid nanocarriers
- Authors: Wa Kasongo, Kasongo
- Date: 2010
- Subjects: Antiretroviral agents HIV infections -- Drug testing Didanosine Nanoparticles Drug delivery systems Nanostructured materials Lipids -- Therapeutic use
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3800 , http://hdl.handle.net/10962/d1003278
- Description: The research undertaken in these studies aimed to investigate the feasibility of developing and manufacturing innovative solid lipid carriers, such as solid lipid nanoparticles (SLN) and/or nanostructured lipid carriers (NLC) using a hot high pressure homogenization method, for didanosine(DDI). In addition, studies using in vitro differential protein adsorption were undertaken to establish whether the SLN and/or NLC have the potential to deliver DDI to the central nervous system (CNS). Prior to initiating pre-formulation, formulation development and optimization studies of DDI-Ioaded SLN and/or NLC, it was necessary to develop and validate an analytical method for the in vitro quantitation and analysis of DDI. An accurate, precise and sensitive RP-HPLC method with UV detection set at 248 nm was developed, optimized and validated for the quantitative in vitro analysis of DDI in formulations. Pre-formulation studies were designed to evaluate the thermal stability of DDI and to select and characterize lipid excipients that may be used for the manufacture of the nanocarriers. It was established that DDI is thermostable at temperatures not exceeding 163°C and therefore a hot high pressure homogenization technique could be used to manufacture DDI-loaded SLN and/or NLC. Lipid screening studies revealed that DDI is poorly soluble in both solid and liquid lipids. A combination of Precirol® ATO 5 and Transcutol® HP was found to have the best solubilizing-potential for DDI of all lipids investigated. The inclusion of Transcutol® HP into Precirol® ATO 5 changed the polymorphic form of the solid lipid from the stable 13-modification to a material that exhibited the co-existence between α- and β-polymorphic forms. The relatively high solubility of DDI in Transcutol® HP compared to Precirol® ATO 5 was an indication that a solid lipid matrix prepared from a binary mixture of Precirol® ATO 5 and Transcutol® HP was likely to have a higher loading capacity and encapsulation efficiency for DDI than a matrix consisting of Precirol® ATO 5 alone. Furthermore, the potential for the solid lipid matrix to exist in the α- and/or β-modifications when Transcutol® HP was added to Precirol® ATO 5 suggested that expulsion of DDI from a solid lipid matrix during prolonged storage periods was likely to be minimal. Therefore it was considered logical to investigate the feasibility of incorporating DDI into NLC and not in SLN. However, due to the limited solubility of DDI in lipids, formulation development of DDI-loaded NLC commenced using small quantities of DDI. Formulation development and optimization studies of DDI-loaded NLC were initially aimed at selecting a surfactant system that was capable of stabilizing NLC in an aqueous environment. Solutol® HS alone or a ternary mixture consisting of Solutol® HS, Tween® 80 and Lutrol® F68 was found to stabilize the nanoparticles in terms of particle size and the polydispersity index. The use of the ternary mixture as the surfactant system was preferred to using Solutol® HS alone as Lutrol® F68 and especially Tween® 80 have been successfully used to target the delivery of API to the brain. Aqueous DDI-free and DDI-Ioaded NLC containing increasing amounts of DDI were manufactured using hot high pressure homogenization at 800 bar for three cycles. The NLC formulations were characterized in terms of particle size, polydispersity index, zeta potential, and polymorphism, degree of crystallinity, encapsulation efficiency (EE), shape and surface morphology. The mean particle size for all formulations was below 250 nm with narrow polydispersity indices, indicating that narrow particle size distribution had been achieved. The d99% values for all formulations tested, were generated using laser diffractometry, and were below 400 nm, with span values ranging from 0.84 - 1.19 also suggesting that a narrow particle size distribution had been achieved. The zeta potential values measured in double distilled water with the conductivity adjusted to 50 μS/cm ranged from -18.4 to -11.4 mV. In addition, all the formulations showed a decrease in the degree of crystallinity as compared to the bulk lipid material and WAXS shows that the formulations existed in a single β-modification form. Furthermore DDI that had been incorporated into the NLC appeared to be molecularly dispersed in the lipid matrices. These parameters remained unaffected for most formulations following storage for two months at 25°C. In addition these formulations contained a mixture of spherical and non-spherical particles irrespective of the amount of DDI that was added during the manufacture of the formulations. These studies showed that it was feasible to develop and incorporate small amounts of DDI into NLC. However in order to use these delivery systems for oral administration of DDI to paediatric patients, strategies to improve the amount of DDI that could be loaded into the particles and to achieve high encapsulation efficiencies had to be developed. The limited solubility of DDI in lipid media was identified as a major factor that affected the loading capacity and encapsulation efficiency of DDI in the NLC. Therefore, a novel strategy aimed at increasing the saturation solubility of DDI in the lipid by attempting to increase the dissolution velocity of the drug in the lipid using a particle size reduction approach, was designed and investigated. DDI was dispersed in Transcutol® HP and the particle size of DDI in the liquid lipid medium was reduced gradually using hot high pressure homogenization and the product obtained from these studies was used to manufacture DDI-loaded NLC using a cold high pressure homogenization procedure. Although the encapsulation efficiency and drug loading following use of this approach was relatively high, the particles were large and showed a tendency to grow in size leading to the formation of microparticles after storage for two months at 25°C. In addition, the degree of crystallinity of the nanoparticles increased rapidly over the same storage period which led to expulsion of DDI nanoparticles for the NLC, despite the DDI loading in NLC being unaffected. It was clearly evident that this new approach of manufacturing solid lipid nanocarriers could be used as a platform not only for enhancing the loading capacity of DDI in solid lipid nanocarriers but also for other hydrophilic drugs. Differential protein adsorption patterns of DDI-loaded NLC were generated in vitro using two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) in order to establish the potential for these systems to deliver DDI to the CNS. NLC formulations containing small amounts of DDI were used as these formulations showed a better stability profile than the formulation with a higher encapsulation efficiency and drug loading capacity. Furthermore, the encapsulation efficiency and drug loading of DDI were considered sufficient for use in 2-D PAGE studies. Data obtained from 2-D PAGE analysis reveal that DDI-loaded NLC preferentially adsorb proteins in vitro that are responsible for specific brain targeting in vivo. More importantly, these studies reveal that in addition to Tween® 80 that has already been shown to have the potential to target CDDS to the brain, Solutol® HS 15 has the potential to achieve a similar objective. Consequently, DDI-loaded NLC have the potential to deliver DDI to the brain and these results may be used as a platform for conducting in vivo studies to establish whether DDI can cross the blood brain barrier and enter the CNS when administered in NLC which may in turn lead to a major breakthrough in the management of HIV/AIDS and Aids Dementia Complex (ADC).
- Full Text:
- Date Issued: 2010
- Authors: Wa Kasongo, Kasongo
- Date: 2010
- Subjects: Antiretroviral agents HIV infections -- Drug testing Didanosine Nanoparticles Drug delivery systems Nanostructured materials Lipids -- Therapeutic use
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3800 , http://hdl.handle.net/10962/d1003278
- Description: The research undertaken in these studies aimed to investigate the feasibility of developing and manufacturing innovative solid lipid carriers, such as solid lipid nanoparticles (SLN) and/or nanostructured lipid carriers (NLC) using a hot high pressure homogenization method, for didanosine(DDI). In addition, studies using in vitro differential protein adsorption were undertaken to establish whether the SLN and/or NLC have the potential to deliver DDI to the central nervous system (CNS). Prior to initiating pre-formulation, formulation development and optimization studies of DDI-Ioaded SLN and/or NLC, it was necessary to develop and validate an analytical method for the in vitro quantitation and analysis of DDI. An accurate, precise and sensitive RP-HPLC method with UV detection set at 248 nm was developed, optimized and validated for the quantitative in vitro analysis of DDI in formulations. Pre-formulation studies were designed to evaluate the thermal stability of DDI and to select and characterize lipid excipients that may be used for the manufacture of the nanocarriers. It was established that DDI is thermostable at temperatures not exceeding 163°C and therefore a hot high pressure homogenization technique could be used to manufacture DDI-loaded SLN and/or NLC. Lipid screening studies revealed that DDI is poorly soluble in both solid and liquid lipids. A combination of Precirol® ATO 5 and Transcutol® HP was found to have the best solubilizing-potential for DDI of all lipids investigated. The inclusion of Transcutol® HP into Precirol® ATO 5 changed the polymorphic form of the solid lipid from the stable 13-modification to a material that exhibited the co-existence between α- and β-polymorphic forms. The relatively high solubility of DDI in Transcutol® HP compared to Precirol® ATO 5 was an indication that a solid lipid matrix prepared from a binary mixture of Precirol® ATO 5 and Transcutol® HP was likely to have a higher loading capacity and encapsulation efficiency for DDI than a matrix consisting of Precirol® ATO 5 alone. Furthermore, the potential for the solid lipid matrix to exist in the α- and/or β-modifications when Transcutol® HP was added to Precirol® ATO 5 suggested that expulsion of DDI from a solid lipid matrix during prolonged storage periods was likely to be minimal. Therefore it was considered logical to investigate the feasibility of incorporating DDI into NLC and not in SLN. However, due to the limited solubility of DDI in lipids, formulation development of DDI-loaded NLC commenced using small quantities of DDI. Formulation development and optimization studies of DDI-loaded NLC were initially aimed at selecting a surfactant system that was capable of stabilizing NLC in an aqueous environment. Solutol® HS alone or a ternary mixture consisting of Solutol® HS, Tween® 80 and Lutrol® F68 was found to stabilize the nanoparticles in terms of particle size and the polydispersity index. The use of the ternary mixture as the surfactant system was preferred to using Solutol® HS alone as Lutrol® F68 and especially Tween® 80 have been successfully used to target the delivery of API to the brain. Aqueous DDI-free and DDI-Ioaded NLC containing increasing amounts of DDI were manufactured using hot high pressure homogenization at 800 bar for three cycles. The NLC formulations were characterized in terms of particle size, polydispersity index, zeta potential, and polymorphism, degree of crystallinity, encapsulation efficiency (EE), shape and surface morphology. The mean particle size for all formulations was below 250 nm with narrow polydispersity indices, indicating that narrow particle size distribution had been achieved. The d99% values for all formulations tested, were generated using laser diffractometry, and were below 400 nm, with span values ranging from 0.84 - 1.19 also suggesting that a narrow particle size distribution had been achieved. The zeta potential values measured in double distilled water with the conductivity adjusted to 50 μS/cm ranged from -18.4 to -11.4 mV. In addition, all the formulations showed a decrease in the degree of crystallinity as compared to the bulk lipid material and WAXS shows that the formulations existed in a single β-modification form. Furthermore DDI that had been incorporated into the NLC appeared to be molecularly dispersed in the lipid matrices. These parameters remained unaffected for most formulations following storage for two months at 25°C. In addition these formulations contained a mixture of spherical and non-spherical particles irrespective of the amount of DDI that was added during the manufacture of the formulations. These studies showed that it was feasible to develop and incorporate small amounts of DDI into NLC. However in order to use these delivery systems for oral administration of DDI to paediatric patients, strategies to improve the amount of DDI that could be loaded into the particles and to achieve high encapsulation efficiencies had to be developed. The limited solubility of DDI in lipid media was identified as a major factor that affected the loading capacity and encapsulation efficiency of DDI in the NLC. Therefore, a novel strategy aimed at increasing the saturation solubility of DDI in the lipid by attempting to increase the dissolution velocity of the drug in the lipid using a particle size reduction approach, was designed and investigated. DDI was dispersed in Transcutol® HP and the particle size of DDI in the liquid lipid medium was reduced gradually using hot high pressure homogenization and the product obtained from these studies was used to manufacture DDI-loaded NLC using a cold high pressure homogenization procedure. Although the encapsulation efficiency and drug loading following use of this approach was relatively high, the particles were large and showed a tendency to grow in size leading to the formation of microparticles after storage for two months at 25°C. In addition, the degree of crystallinity of the nanoparticles increased rapidly over the same storage period which led to expulsion of DDI nanoparticles for the NLC, despite the DDI loading in NLC being unaffected. It was clearly evident that this new approach of manufacturing solid lipid nanocarriers could be used as a platform not only for enhancing the loading capacity of DDI in solid lipid nanocarriers but also for other hydrophilic drugs. Differential protein adsorption patterns of DDI-loaded NLC were generated in vitro using two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) in order to establish the potential for these systems to deliver DDI to the CNS. NLC formulations containing small amounts of DDI were used as these formulations showed a better stability profile than the formulation with a higher encapsulation efficiency and drug loading capacity. Furthermore, the encapsulation efficiency and drug loading of DDI were considered sufficient for use in 2-D PAGE studies. Data obtained from 2-D PAGE analysis reveal that DDI-loaded NLC preferentially adsorb proteins in vitro that are responsible for specific brain targeting in vivo. More importantly, these studies reveal that in addition to Tween® 80 that has already been shown to have the potential to target CDDS to the brain, Solutol® HS 15 has the potential to achieve a similar objective. Consequently, DDI-loaded NLC have the potential to deliver DDI to the brain and these results may be used as a platform for conducting in vivo studies to establish whether DDI can cross the blood brain barrier and enter the CNS when administered in NLC which may in turn lead to a major breakthrough in the management of HIV/AIDS and Aids Dementia Complex (ADC).
- Full Text:
- Date Issued: 2010
An investigation of financial and operational efficiency of pension funds in Kenya
- Authors: Njuguna, Amos Gitau
- Date: 2010
- Subjects: Pension trusts -- Kenya , Pension trusts -- Kenya -- Management , Pension trusts -- Investments -- Kenya , Retirement income -- Kenya , Retirees -- Kenya -- Finance, Personal
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8679 , http://hdl.handle.net/10948/1144 , Pension trusts -- Kenya , Pension trusts -- Kenya -- Management , Pension trusts -- Investments -- Kenya , Retirement income -- Kenya , Retirees -- Kenya -- Finance, Personal
- Description: Pension funds are the principal sources of retirement income for millions of people in the world. Pension funds are also important contributors to the gross domestic product (GDP) of countries. This study focuses on pension funds in Kenya. Retirement income accounts for 68 percent of the total income of retirees in Kenya, while pension assets account for 30 percent of Kenya’s GDP. It is therefore important that pension funds be managed effectively, not only in Kenya, but also in other countries. The primary objective of the study is to investigate ways of enhancing pension fund efficiency by establishing the determinants of such efficiency. More specifically, the study explores the effect that the organisational culture, regulations, investment strategy, ethics, risk management, design, size and the age profile of members of pension funds exert on the efficiency of these funds. A sample of 749 pension funds was drawn from the Kenyan Retirement Benefits Authority (RBA) register. The sample selection was based on the criterion that these pension funds should have been in existence within the period 2001 to 2008. Seven hundred and forty-nine (749) questionnaires were mailed to the trustees of these pension funds. Three hundred and sixty-two (362) usable questionnaires were returned, which translated into a response rate of 48.3 per cent. Except for financial efficiency, self-constructed instruments based on secondary literature reviews were used to measure the variables in the hypothesised model to improve pension fund efficiency. Appropriate steps were taken to ensure the validity and reliability of these measuring instruments. The empirical results revealed that leadership, governance, regulations, design, membership age and size of funds had no significant influence on operational efficiency of these funds. The results further showed that the membership age, design, regulations and operational efficiency of pension funds exerted no significant influence on their financial efficiency. The results also revealed that the membership age, size and design of pension funds did not influence how these funds were led by their leadership. iv The empirical results however showed that smaller pension funds were perceived to exhibit better financial efficiency, while pension funds with membership aged 31 - 40 were perceived to be better governed compared to other age groups. Finally, in rigorous structural equation analyses, no significant relationships were found between fund regulations (independent variable), on the one hand, and fund governance and leadership (dependent variables), on the other hand. Use of simple linear regression however disclosed a significant positive relationship between the afore-mentioned independent variable and dependent variables.
- Full Text:
- Date Issued: 2010
- Authors: Njuguna, Amos Gitau
- Date: 2010
- Subjects: Pension trusts -- Kenya , Pension trusts -- Kenya -- Management , Pension trusts -- Investments -- Kenya , Retirement income -- Kenya , Retirees -- Kenya -- Finance, Personal
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8679 , http://hdl.handle.net/10948/1144 , Pension trusts -- Kenya , Pension trusts -- Kenya -- Management , Pension trusts -- Investments -- Kenya , Retirement income -- Kenya , Retirees -- Kenya -- Finance, Personal
- Description: Pension funds are the principal sources of retirement income for millions of people in the world. Pension funds are also important contributors to the gross domestic product (GDP) of countries. This study focuses on pension funds in Kenya. Retirement income accounts for 68 percent of the total income of retirees in Kenya, while pension assets account for 30 percent of Kenya’s GDP. It is therefore important that pension funds be managed effectively, not only in Kenya, but also in other countries. The primary objective of the study is to investigate ways of enhancing pension fund efficiency by establishing the determinants of such efficiency. More specifically, the study explores the effect that the organisational culture, regulations, investment strategy, ethics, risk management, design, size and the age profile of members of pension funds exert on the efficiency of these funds. A sample of 749 pension funds was drawn from the Kenyan Retirement Benefits Authority (RBA) register. The sample selection was based on the criterion that these pension funds should have been in existence within the period 2001 to 2008. Seven hundred and forty-nine (749) questionnaires were mailed to the trustees of these pension funds. Three hundred and sixty-two (362) usable questionnaires were returned, which translated into a response rate of 48.3 per cent. Except for financial efficiency, self-constructed instruments based on secondary literature reviews were used to measure the variables in the hypothesised model to improve pension fund efficiency. Appropriate steps were taken to ensure the validity and reliability of these measuring instruments. The empirical results revealed that leadership, governance, regulations, design, membership age and size of funds had no significant influence on operational efficiency of these funds. The results further showed that the membership age, design, regulations and operational efficiency of pension funds exerted no significant influence on their financial efficiency. The results also revealed that the membership age, size and design of pension funds did not influence how these funds were led by their leadership. iv The empirical results however showed that smaller pension funds were perceived to exhibit better financial efficiency, while pension funds with membership aged 31 - 40 were perceived to be better governed compared to other age groups. Finally, in rigorous structural equation analyses, no significant relationships were found between fund regulations (independent variable), on the one hand, and fund governance and leadership (dependent variables), on the other hand. Use of simple linear regression however disclosed a significant positive relationship between the afore-mentioned independent variable and dependent variables.
- Full Text:
- Date Issued: 2010
An investigation of IgE regulation by recombinant soluble IgE receptors and co-receptors in human cell culture models
- Authors: Bowles, Sandra Lyn
- Date: 2010
- Subjects: Immunoglobulin E , Allergy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10321 , http://hdl.handle.net/10948/1231 , Immunoglobulin E , Allergy
- Description: Type I hypersensitivities are mediated by the IgE antibody. The effector functions and synthesis of IgE result from interactions with a network of proteins that include a high affinity (FcRIα) and a low affinity (CD23, FcRII) Fc receptor in conjunction with the B lymphocyte receptor, CD21. CD23 is a multifunctional type II transmembrane protein that binds its known ligands through its ectodomain either as a membrane-bound or soluble receptor generated in vivo by specific proteolytic cleavages. IgE production is primarily regulated by interactions between IgE, CD23 and CD21. Despite its importance for development of strategies to limit hypersensitivity, precise information about the molecular interactions remains limited. During this study, I engineered, expressed and purified from bacteria three soluble human CD23 fragments that are normally formed in vivo and shed from the cell surface (1) derCD23, amino acids 156-298 (2) sCD23, amino acids 150-321 and (3) the entire ectodomain, exCD23, amino acids 48-321 to examine the comparative binding of recombinant human CD21 SCR 1-2 and native human IgE to these fragments. Gel filtration HPLC revealed that derCD23 and sCD23 were monomeric whereas exCD23 assembled as a heterogeneous mixture that included trimers and monomers. At the concentrations utilized, CD23 fragments sCD23 and exCD23 bound CD21 with similar affinity, whereas interaction between derCD23 and CD21 was minimal when analyzed by surface plasmon resonance (SPR) spectroscopy. These findings suggest that penultimate “tail” amino acids between 298 and 321 stabilize CD21 attachment, although it cannot be ruled out, the region between Met 150 and Ser 156 may also play a role in binding CD21 SCR 1-2. In contrast, there is a progressive increment in the affinity of soluble fragments (exCD23>sCD23>derCD23) for IgE, upon increasing length of the proximal CD23 “stalk” domain. These findings highlight the differences in both the structural basis and affinity of the three physiological fragments of human CD23 for the ligands CD21 and IgE and underscore the complexity of CD23-mediated regulatory networks. It was found that B-cells only make up ~5% of the PBMC population, and that these cells were able to be activated, via STAT-6 phosphorylation, to enter class switch recombination (CSR) by the addition of switch factors (IL-4 and anti-CD40). Titration experiments dictated that 25 ng/mL of CD23 was the most efficient concentration to up-regulate IgE synthesis in PBMCs; furthermore, soluble CD23 proteins were incubated with PBMCs in the presence and absence of CD21 SCR 1-2 to investigate the effect that these recombinant proteins have on IgE synthesis. Results showed that the influence of recombinant proteins (both CD23 and CD21) on IgE synthesis was slight. It was shown that while derCD23 had no significant effect, monomeric sCD23 down-regulated, and the mixture of monomeric and oligomeric exCD23 up-regulated IgE synthesis. On addition of CD21 SCR 1-2 to the cells switched and treated with soluble CD23, it was found that in both cases for sCD23 and exCD23, IgE synthesis was increased, while for derCD23, there was no noticeable difference in IgE synthesis. This confirmed previous data showing the lack of binding between derCD23 and CD21 SCR 1-2. The exact binding site for CD21 on the CD23 molecule is unknown, and incompletely represented in the NMR and crystal structures. It is thought that CD21 binds to the C-terminal tail section, not present in derCD23. It is therefore likely that only a negative-feedback mechanism operates with derCD23 to regulate IgE synthesis. Further investigation of the binding of CD23 fragments to SCR 5-8 of CD21 and the effect of this on IgE synthesis may lead to a potential therapeutic role for derCD23 in the treatment of allergic disease. Data accumulated in this study suggests that investigating the modulation of oligomeric state and thus the activity of soluble CD23 fragments may be important in the construction of new regulators of IgE synthesis.
- Full Text:
- Date Issued: 2010
- Authors: Bowles, Sandra Lyn
- Date: 2010
- Subjects: Immunoglobulin E , Allergy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10321 , http://hdl.handle.net/10948/1231 , Immunoglobulin E , Allergy
- Description: Type I hypersensitivities are mediated by the IgE antibody. The effector functions and synthesis of IgE result from interactions with a network of proteins that include a high affinity (FcRIα) and a low affinity (CD23, FcRII) Fc receptor in conjunction with the B lymphocyte receptor, CD21. CD23 is a multifunctional type II transmembrane protein that binds its known ligands through its ectodomain either as a membrane-bound or soluble receptor generated in vivo by specific proteolytic cleavages. IgE production is primarily regulated by interactions between IgE, CD23 and CD21. Despite its importance for development of strategies to limit hypersensitivity, precise information about the molecular interactions remains limited. During this study, I engineered, expressed and purified from bacteria three soluble human CD23 fragments that are normally formed in vivo and shed from the cell surface (1) derCD23, amino acids 156-298 (2) sCD23, amino acids 150-321 and (3) the entire ectodomain, exCD23, amino acids 48-321 to examine the comparative binding of recombinant human CD21 SCR 1-2 and native human IgE to these fragments. Gel filtration HPLC revealed that derCD23 and sCD23 were monomeric whereas exCD23 assembled as a heterogeneous mixture that included trimers and monomers. At the concentrations utilized, CD23 fragments sCD23 and exCD23 bound CD21 with similar affinity, whereas interaction between derCD23 and CD21 was minimal when analyzed by surface plasmon resonance (SPR) spectroscopy. These findings suggest that penultimate “tail” amino acids between 298 and 321 stabilize CD21 attachment, although it cannot be ruled out, the region between Met 150 and Ser 156 may also play a role in binding CD21 SCR 1-2. In contrast, there is a progressive increment in the affinity of soluble fragments (exCD23>sCD23>derCD23) for IgE, upon increasing length of the proximal CD23 “stalk” domain. These findings highlight the differences in both the structural basis and affinity of the three physiological fragments of human CD23 for the ligands CD21 and IgE and underscore the complexity of CD23-mediated regulatory networks. It was found that B-cells only make up ~5% of the PBMC population, and that these cells were able to be activated, via STAT-6 phosphorylation, to enter class switch recombination (CSR) by the addition of switch factors (IL-4 and anti-CD40). Titration experiments dictated that 25 ng/mL of CD23 was the most efficient concentration to up-regulate IgE synthesis in PBMCs; furthermore, soluble CD23 proteins were incubated with PBMCs in the presence and absence of CD21 SCR 1-2 to investigate the effect that these recombinant proteins have on IgE synthesis. Results showed that the influence of recombinant proteins (both CD23 and CD21) on IgE synthesis was slight. It was shown that while derCD23 had no significant effect, monomeric sCD23 down-regulated, and the mixture of monomeric and oligomeric exCD23 up-regulated IgE synthesis. On addition of CD21 SCR 1-2 to the cells switched and treated with soluble CD23, it was found that in both cases for sCD23 and exCD23, IgE synthesis was increased, while for derCD23, there was no noticeable difference in IgE synthesis. This confirmed previous data showing the lack of binding between derCD23 and CD21 SCR 1-2. The exact binding site for CD21 on the CD23 molecule is unknown, and incompletely represented in the NMR and crystal structures. It is thought that CD21 binds to the C-terminal tail section, not present in derCD23. It is therefore likely that only a negative-feedback mechanism operates with derCD23 to regulate IgE synthesis. Further investigation of the binding of CD23 fragments to SCR 5-8 of CD21 and the effect of this on IgE synthesis may lead to a potential therapeutic role for derCD23 in the treatment of allergic disease. Data accumulated in this study suggests that investigating the modulation of oligomeric state and thus the activity of soluble CD23 fragments may be important in the construction of new regulators of IgE synthesis.
- Full Text:
- Date Issued: 2010