On the characterization of photovoltaic devices for concentrator purposes
- Authors: Vorster, Frederick Jacobus
- Date: 2007
- Subjects: Photovoltaic cells , Image processing , Solar cells
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10530 , http://hdl.handle.net/10948/639 , Photovoltaic cells , Image processing , Solar cells
- Description: This study originated from an evaluation of the performance of a commercially available high concentration point focus concentrator PV system. The effect of module design flaws was studied by using current-voltage (I-V) curves obtained from each module in the array. The position of reverse bias steps revealed the severity of mismatch in a string of series-connected cells. By understanding the effects of the various types of mismatch, power losses and damage to the solar cells resulting from hot spot formation can be minimized and several recommendations for improving the basic performance of similar systems were made. Concern over the extent and type of defect failure of the concentrator photovoltaic (CPV) cells prompted an investigation into the use of a light beam induced current (LBIC) technique to investigate the spatial distribution of defects. An overview of current and developing LBIC techniques revealed that the original standard LBIC techniques have found widespread application, and that far-reaching and important developments of the technique have taken place over the years. These developments are driven by natural progression as well as the availability of newly developed advanced measurement equipment. Several techniques such as Lock-in hermography and the use of infrared cameras have developed as complementary techniques to advanced LBIC techniques. As an accurate contactless evaluation tool that is able to image spatially distributed defects in cell material, the basis of this method seemed promising for the evaluation of concentrator cells.
- Full Text:
- Date Issued: 2007
- Authors: Vorster, Frederick Jacobus
- Date: 2007
- Subjects: Photovoltaic cells , Image processing , Solar cells
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10530 , http://hdl.handle.net/10948/639 , Photovoltaic cells , Image processing , Solar cells
- Description: This study originated from an evaluation of the performance of a commercially available high concentration point focus concentrator PV system. The effect of module design flaws was studied by using current-voltage (I-V) curves obtained from each module in the array. The position of reverse bias steps revealed the severity of mismatch in a string of series-connected cells. By understanding the effects of the various types of mismatch, power losses and damage to the solar cells resulting from hot spot formation can be minimized and several recommendations for improving the basic performance of similar systems were made. Concern over the extent and type of defect failure of the concentrator photovoltaic (CPV) cells prompted an investigation into the use of a light beam induced current (LBIC) technique to investigate the spatial distribution of defects. An overview of current and developing LBIC techniques revealed that the original standard LBIC techniques have found widespread application, and that far-reaching and important developments of the technique have taken place over the years. These developments are driven by natural progression as well as the availability of newly developed advanced measurement equipment. Several techniques such as Lock-in hermography and the use of infrared cameras have developed as complementary techniques to advanced LBIC techniques. As an accurate contactless evaluation tool that is able to image spatially distributed defects in cell material, the basis of this method seemed promising for the evaluation of concentrator cells.
- Full Text:
- Date Issued: 2007
International trade and environmental disputes : an analysis of Article XX of the General Agreement on Tariffs and Trade (1994) and environmental policies of the developing and developed world
- Authors: Manjoro, Faith Tendayi
- Date: 2007
- Subjects: World Trade Organization General Agreement on Tariffs and Trade (Organization) Environmental protection Environmental degradation Free trade -- Environmental aspects Foreign trade regulation International trade
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3713 , http://hdl.handle.net/10962/d1007444
- Description: A major problem emanating from the trade/environment conflict is the use of trade measures, such as restrictions and sanctions, as tools for environmental protection. Proponents of free trade argue that the use of these measures is tantamount to abuse of environmental standards for protectionist ends. This is particularly so if the imposition of the standard amounts to a unilateral act which blocks the entry of a specified product into the market of another member state for reasons other than environmental protection. Environmentalists at the same time argue that free trade will lead to environmental degradation and therefore advocate for the use of trade-restrictive measures to safeguard against the destruction of the environment. The GATT has proved problematic when it comes to the resolution of trade/environment conflicts. The GATT aims at trade liberalisation yet most environmental policies are enforced through trade-restrictive devices like quotas and licences. Article XX of the GATT is anomalous: it does not explicitly mention the environment, yet member states rely on it as an environmental protection clause. This thesis discusses the various issues emanating from the trade/environmental debate. The history of Article XX is reviewed and the issues that arise in the adjudication of Articles XX (b) and (g) in a trade/environment context are analysed in light of the decisions by the GATTIWTO dispute settlement bodies. The role played by Multilateral Environmental Agreements (MEAs) in protecting the environment is discussed. However, the relationship between MEAs and the WTO is also scrutinised as these rule-making bodies often come into conflict: firstly, because they serve two differing interests - on the one hand, MEAs allow for the use of trade restrictive measures in environmental agreements and on the other, the WTO calls for unrestricted trade unless exceptional circumstances exist; and secondly, member states that are party to both the WTO and MEAs are often forced to subscribe to international trade rules that are incompatible with those in environmental agreements. The trade/environmental debate is important to both the developed and developing worlds. The developed world is in favour of environmental policies which protect the environment from degradation. On the other hand, the developing world is in desperate need of the benefits of trade liberalisation so as to cater for high unemployment rates and poor economic growth. The question thus arises as to whether, when environmental issues are promoted, developing countries will not suffer at the expense of developed nations which may engage in protectionist measures under the pretext of environmental conservation. The divide between developed and developing countries is illustrated in Chapter 5 through case studies on coal mining in the USA and South Africa. The conclusion reached is that total co-operation is essential between developed and developing states for success in safeguarding the environment from degradation. Accordingly, the trade/environmental debate cannot be isolated from the conflicting approaches in developed and developing countries. The conclusions in the final chapter seek to strike a balance between trade liberalisation and environmental protection. Recommendations are made on how the trade/environmental challenges could be dealt with and the regulation of trade restrictive devices to exclude, or at least limit, protectionism.
- Full Text:
- Date Issued: 2007
- Authors: Manjoro, Faith Tendayi
- Date: 2007
- Subjects: World Trade Organization General Agreement on Tariffs and Trade (Organization) Environmental protection Environmental degradation Free trade -- Environmental aspects Foreign trade regulation International trade
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3713 , http://hdl.handle.net/10962/d1007444
- Description: A major problem emanating from the trade/environment conflict is the use of trade measures, such as restrictions and sanctions, as tools for environmental protection. Proponents of free trade argue that the use of these measures is tantamount to abuse of environmental standards for protectionist ends. This is particularly so if the imposition of the standard amounts to a unilateral act which blocks the entry of a specified product into the market of another member state for reasons other than environmental protection. Environmentalists at the same time argue that free trade will lead to environmental degradation and therefore advocate for the use of trade-restrictive measures to safeguard against the destruction of the environment. The GATT has proved problematic when it comes to the resolution of trade/environment conflicts. The GATT aims at trade liberalisation yet most environmental policies are enforced through trade-restrictive devices like quotas and licences. Article XX of the GATT is anomalous: it does not explicitly mention the environment, yet member states rely on it as an environmental protection clause. This thesis discusses the various issues emanating from the trade/environmental debate. The history of Article XX is reviewed and the issues that arise in the adjudication of Articles XX (b) and (g) in a trade/environment context are analysed in light of the decisions by the GATTIWTO dispute settlement bodies. The role played by Multilateral Environmental Agreements (MEAs) in protecting the environment is discussed. However, the relationship between MEAs and the WTO is also scrutinised as these rule-making bodies often come into conflict: firstly, because they serve two differing interests - on the one hand, MEAs allow for the use of trade restrictive measures in environmental agreements and on the other, the WTO calls for unrestricted trade unless exceptional circumstances exist; and secondly, member states that are party to both the WTO and MEAs are often forced to subscribe to international trade rules that are incompatible with those in environmental agreements. The trade/environmental debate is important to both the developed and developing worlds. The developed world is in favour of environmental policies which protect the environment from degradation. On the other hand, the developing world is in desperate need of the benefits of trade liberalisation so as to cater for high unemployment rates and poor economic growth. The question thus arises as to whether, when environmental issues are promoted, developing countries will not suffer at the expense of developed nations which may engage in protectionist measures under the pretext of environmental conservation. The divide between developed and developing countries is illustrated in Chapter 5 through case studies on coal mining in the USA and South Africa. The conclusion reached is that total co-operation is essential between developed and developing states for success in safeguarding the environment from degradation. Accordingly, the trade/environmental debate cannot be isolated from the conflicting approaches in developed and developing countries. The conclusions in the final chapter seek to strike a balance between trade liberalisation and environmental protection. Recommendations are made on how the trade/environmental challenges could be dealt with and the regulation of trade restrictive devices to exclude, or at least limit, protectionism.
- Full Text:
- Date Issued: 2007
The application of quality models and techniques in selected SMMEs in the Eastern Cape
- Authors: Murray, Andrew Thomas
- Date: 2007
- Subjects: Business enterprises -- South Africa -- Eastern Cape , Quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9608 , http://hdl.handle.net/10948/832 , Business enterprises -- South Africa -- Eastern Cape , Quality management -- South Africa -- Eastern Cape
- Description: With the increase of imports from China and more pressure being put on the Small, Medium and Micro enterprises (SMME’s) from their larger customers, survival has become more and more difficult, quality is no longer being a choise but a prerequisite if the companies want to survive. This research evaluates the use of quality and productivity or the lack thereof in selected SMMEs in the Eastern Cape environment from both the SMME and Larger companies’ point of view. The research has focused on the effectiveness and understanding of what has been put in place by the SMMEs, what is available for the SMMEs to use, governmental support, and the requirements of the customers. Certain shortcomings have been highlighted as to the use and benefits of the processes that have been implemented. The researcher made use of both quantitative and qualitative data to determine the outcome of the research. The thesis concludes that the SMME sector knows the importance of the use of quality; it is the effectiveness and management thereof that is the concern.
- Full Text:
- Date Issued: 2007
- Authors: Murray, Andrew Thomas
- Date: 2007
- Subjects: Business enterprises -- South Africa -- Eastern Cape , Quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9608 , http://hdl.handle.net/10948/832 , Business enterprises -- South Africa -- Eastern Cape , Quality management -- South Africa -- Eastern Cape
- Description: With the increase of imports from China and more pressure being put on the Small, Medium and Micro enterprises (SMME’s) from their larger customers, survival has become more and more difficult, quality is no longer being a choise but a prerequisite if the companies want to survive. This research evaluates the use of quality and productivity or the lack thereof in selected SMMEs in the Eastern Cape environment from both the SMME and Larger companies’ point of view. The research has focused on the effectiveness and understanding of what has been put in place by the SMMEs, what is available for the SMMEs to use, governmental support, and the requirements of the customers. Certain shortcomings have been highlighted as to the use and benefits of the processes that have been implemented. The researcher made use of both quantitative and qualitative data to determine the outcome of the research. The thesis concludes that the SMME sector knows the importance of the use of quality; it is the effectiveness and management thereof that is the concern.
- Full Text:
- Date Issued: 2007
Assessment of antibacterial potentials of Garcinia Kola seed extracts and their interactions with antibiotics
- Authors: Sibanda, Thulani
- Date: 2007
- Subjects: Drug resistance in microorganisms , Garcinia , Antibiotics , Medicinal plants
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11242 , http://hdl.handle.net/10353/71 , Drug resistance in microorganisms , Garcinia , Antibiotics , Medicinal plants
- Description: The antibacterial potency of the extracts of the seed of Garcinia kola (bitter kola) was investigated in this study against a panel of referenced, environmental and clinical bacterial strains. The killing rates of the active extract as well as their potential for combination antibacterial therapy with standard antibiotics were also elucidated using standard procedures. The aqueous and acetone extracts of the seed were screened for activity against 27 bacterial isolates. The aqueous extract exhibited activity mainly against Gram positive organisms with Minimum inhibitory concentration (MIC) values ranging from 5 mgml-1 – 20 mgml-1, while the acetone extract showed activity against both Gram negative and Gram positive organisms with MIC values ranging from 10 mgml-1 - 0.156 mgml-1. The acetone extract also showed rapid bactericidal activity against Staphylococcus aureus ATCC 6538 with a 3.097 Log10 reduction in counts within 4 hours at 0.3125 mgml-1 and a 1.582 Log10 reduction against Proteus vulgaris CSIR 0030 at 5 mgml-1 after 1 hour. In addition, the aqueous, methanol and acetone extracts of the seeds also exhibited activity against four clinical strains of Staphylococcus isolated from wound sepsis specimens. The MIC values for the aqueous extract were 10 mgml-1 for all the isolates while the acetone and methanol extracts had lower values ranging from 0.3125 - 0.625 mgml-1. The acetone extract was strongly bactericidal against Staphylococcus aureus OKOH3 resulting in a 2.70 Log10 reduction in counts at 1.25 mgml-1 within 4 hours of exposure and a complete elimination of the organism after 8 hours. The bactericidal vi activity of the same extract against Staphylococcus aureus OKOH1 was weak, achieving only a 2.92 Log10 reduction in counts at 1.25 mgml-1 (4× MIC) in 24 hours. In the test for interactions between the acetone extract of the seeds and antibiotics, synergistic interactions were observed largely against Gram positive organisms using the FIC indices, (indices of 0.52 - 0.875) with combinations against Gram negatives yielding largely antagonistic interactions (indices of 2.0 to 5.0). Synergy (≥ 1000 times or ≥ 3 Log10 potentiation of the bactericidal activity) against both Gram negative and Gram positive organisms was detected by time kill assays mainly involving the antibiotics tetracycline, chloramphenicol, amoxycillin and penicillin G. Combinations involving erythromycin and ciprofloxacin consistently gave antagonistic or indifferent interactions. We conclude that the acetone extract of Garcinia kola seeds possess strong bactericidal activities against both Gram positive and Gram negative organisms and can be therapeutically useful in the treatment of bacterial infections including the problematic staphylococcal wound infections. In addition, the acetone extract can be a potential source of broad spectrum resistance modifying compounds that can potentially improve the performance of antibiotics in the treatment of drug resistant infections.
- Full Text:
- Date Issued: 2007
- Authors: Sibanda, Thulani
- Date: 2007
- Subjects: Drug resistance in microorganisms , Garcinia , Antibiotics , Medicinal plants
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11242 , http://hdl.handle.net/10353/71 , Drug resistance in microorganisms , Garcinia , Antibiotics , Medicinal plants
- Description: The antibacterial potency of the extracts of the seed of Garcinia kola (bitter kola) was investigated in this study against a panel of referenced, environmental and clinical bacterial strains. The killing rates of the active extract as well as their potential for combination antibacterial therapy with standard antibiotics were also elucidated using standard procedures. The aqueous and acetone extracts of the seed were screened for activity against 27 bacterial isolates. The aqueous extract exhibited activity mainly against Gram positive organisms with Minimum inhibitory concentration (MIC) values ranging from 5 mgml-1 – 20 mgml-1, while the acetone extract showed activity against both Gram negative and Gram positive organisms with MIC values ranging from 10 mgml-1 - 0.156 mgml-1. The acetone extract also showed rapid bactericidal activity against Staphylococcus aureus ATCC 6538 with a 3.097 Log10 reduction in counts within 4 hours at 0.3125 mgml-1 and a 1.582 Log10 reduction against Proteus vulgaris CSIR 0030 at 5 mgml-1 after 1 hour. In addition, the aqueous, methanol and acetone extracts of the seeds also exhibited activity against four clinical strains of Staphylococcus isolated from wound sepsis specimens. The MIC values for the aqueous extract were 10 mgml-1 for all the isolates while the acetone and methanol extracts had lower values ranging from 0.3125 - 0.625 mgml-1. The acetone extract was strongly bactericidal against Staphylococcus aureus OKOH3 resulting in a 2.70 Log10 reduction in counts at 1.25 mgml-1 within 4 hours of exposure and a complete elimination of the organism after 8 hours. The bactericidal vi activity of the same extract against Staphylococcus aureus OKOH1 was weak, achieving only a 2.92 Log10 reduction in counts at 1.25 mgml-1 (4× MIC) in 24 hours. In the test for interactions between the acetone extract of the seeds and antibiotics, synergistic interactions were observed largely against Gram positive organisms using the FIC indices, (indices of 0.52 - 0.875) with combinations against Gram negatives yielding largely antagonistic interactions (indices of 2.0 to 5.0). Synergy (≥ 1000 times or ≥ 3 Log10 potentiation of the bactericidal activity) against both Gram negative and Gram positive organisms was detected by time kill assays mainly involving the antibiotics tetracycline, chloramphenicol, amoxycillin and penicillin G. Combinations involving erythromycin and ciprofloxacin consistently gave antagonistic or indifferent interactions. We conclude that the acetone extract of Garcinia kola seeds possess strong bactericidal activities against both Gram positive and Gram negative organisms and can be therapeutically useful in the treatment of bacterial infections including the problematic staphylococcal wound infections. In addition, the acetone extract can be a potential source of broad spectrum resistance modifying compounds that can potentially improve the performance of antibiotics in the treatment of drug resistant infections.
- Full Text:
- Date Issued: 2007
Ubuchule bencoko yababini nesimbo sokubhala kwincwadi ka A.M. Mmango ethi, "Law' ilahle"
- Authors: Tose, M. J
- Date: 2007
- Subjects: Mmango, A. M. -- Criticism and interpretation , Mmango, A. M. Law' ilahle , Xhosa fiction -- History and criticism
- Language: Xhosa
- Type: Thesis , Masters , MA
- Identifier: vital:8467 , http://hdl.handle.net/10948/621 , Mmango, A. M. -- Criticism and interpretation , Mmango, A. M. Law' ilahle , Xhosa fiction -- History and criticism
- Description: Olu phando lugxile kakhulu kwincwadi ka-A.M. Mmango ethi, Law’ilahle. Apha sizama ukuveza ukubaluleka kobuchule bokubhala phakathi kwencoko yabantu ababini kubhalo lwemidlalo ngoovulindlela bedrama esiXhoseni. Oku kwenziwa ngokuthi kuphononongwe nzulu isimbo sokubhala. Ezinye izinto esiza kuziveza ziindlela zokuthetha ezithi zizesetyenziswe ngabalinganiswa. Oku kwenziwa ngokuthi kugxeleshwe kakhulu kumagama namaganyana adelelekileyo asetyeniswayo ngabalinganiswa ze kuthi kubuywe kukhangelwe nefuthe laloo magama kulwimi olusulungekileyo lwesiXhosa. Oku kukhokelela ekuphononongeni indlela ekuthi umbhali asebenzise ngayo isigama esivumelekileyo nesigama esithi sisetyenziswe esibangela ukuba umfundi lowo asebenzise ingqondo yakhe ukucinga ukuba kutheni umbhali etshintsha isigama kuloo ncoko ithile ayakhayo. U-A. M. Mmango usizobela asivezele kakuhle zonke izigaba ekufuneka zilandelwe xa sibhala uncwadi lwedrama. Uyaphumelele ke ukuziveza zonke ezi zinto ngenxa yeengxoxo azakhayo phakathi kwabalinganiswa. Ukuba sithelekisa uluncwadi lwedrama yale mihla luye lube nawo umahluko kuncwadi olwalubhalwe kuqala. Kananjalo, lo ka-Mmango usebenzisa uyilo lwengxoxo nocwangciso lwimi olululo ukwenzela ukuba umfundi lowo ofunda incwadi yakhe akwazi ukuwubona umahluko phakathi kwababhali bale mihla nabakudala. Esi simbo sikaMmango sokubhala asiwenzi umdintsi. Oku kuphawuleka ngamandla kwimixholwana esekeleze ululeko olungqongqo.
- Full Text:
- Date Issued: 2007
- Authors: Tose, M. J
- Date: 2007
- Subjects: Mmango, A. M. -- Criticism and interpretation , Mmango, A. M. Law' ilahle , Xhosa fiction -- History and criticism
- Language: Xhosa
- Type: Thesis , Masters , MA
- Identifier: vital:8467 , http://hdl.handle.net/10948/621 , Mmango, A. M. -- Criticism and interpretation , Mmango, A. M. Law' ilahle , Xhosa fiction -- History and criticism
- Description: Olu phando lugxile kakhulu kwincwadi ka-A.M. Mmango ethi, Law’ilahle. Apha sizama ukuveza ukubaluleka kobuchule bokubhala phakathi kwencoko yabantu ababini kubhalo lwemidlalo ngoovulindlela bedrama esiXhoseni. Oku kwenziwa ngokuthi kuphononongwe nzulu isimbo sokubhala. Ezinye izinto esiza kuziveza ziindlela zokuthetha ezithi zizesetyenziswe ngabalinganiswa. Oku kwenziwa ngokuthi kugxeleshwe kakhulu kumagama namaganyana adelelekileyo asetyeniswayo ngabalinganiswa ze kuthi kubuywe kukhangelwe nefuthe laloo magama kulwimi olusulungekileyo lwesiXhosa. Oku kukhokelela ekuphononongeni indlela ekuthi umbhali asebenzise ngayo isigama esivumelekileyo nesigama esithi sisetyenziswe esibangela ukuba umfundi lowo asebenzise ingqondo yakhe ukucinga ukuba kutheni umbhali etshintsha isigama kuloo ncoko ithile ayakhayo. U-A. M. Mmango usizobela asivezele kakuhle zonke izigaba ekufuneka zilandelwe xa sibhala uncwadi lwedrama. Uyaphumelele ke ukuziveza zonke ezi zinto ngenxa yeengxoxo azakhayo phakathi kwabalinganiswa. Ukuba sithelekisa uluncwadi lwedrama yale mihla luye lube nawo umahluko kuncwadi olwalubhalwe kuqala. Kananjalo, lo ka-Mmango usebenzisa uyilo lwengxoxo nocwangciso lwimi olululo ukwenzela ukuba umfundi lowo ofunda incwadi yakhe akwazi ukuwubona umahluko phakathi kwababhali bale mihla nabakudala. Esi simbo sikaMmango sokubhala asiwenzi umdintsi. Oku kuphawuleka ngamandla kwimixholwana esekeleze ululeko olungqongqo.
- Full Text:
- Date Issued: 2007
Studies towards the development of novel multidentate ligands
- Authors: Magqi, Nceba
- Date: 2007
- Subjects: Density functionals , Ligands , Ligands -- Design , Ligands -- Analysis , Camphor
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4358 , http://hdl.handle.net/10962/d1005023 , Density functionals , Ligands , Ligands -- Design , Ligands -- Analysis , Camphor
- Description: In this study, attention has been given to the design and synthesis of novel multidentate ligands for use in the construction of ruthenium-based metathesis catalysts, and their chelating potential has been explored by computer modelling at the Density Functional Theory (DFT) level. Both Kemp’s triacid (1,3,5-trimethyl-1,3,5-cyclohexanetricarboxylic acid) and D-(+)-camphor have been investigated as molecular scaffolds for the development of such ligands. However selective elaboration of the functional groups in Kemp’s triacid proved difficult to achieve, and the research has focused on the development of camphor derivatives. The synthesis of the camphor-based ligands has involved C-8 functionalisation and ring-opening of the bicyclic system to afford tridentate products. The formation of 9-iodocamphorquinone bis(ethylene ketal) together with the desired product, the 8-iodo isomer, has been confirmed by single crystal X-ray analysis of both compounds. Formation of the 9-iodo analogue has provided new insights into the intramolecular rearrangement of camphor skeleton, and the mechanistic implications have been assessed by coset analysis. Attempts to effect nucleophilic displacement of the 8-halogeno groups by nucleophilic donor moieties proved unexpectedly difficult and, coupled with the susceptibility of the carbonyl groups to nucleophilic attack, has led to the formation of novel tricyclic products, viz., 1,6-dimethyl-3-(2-pyridylamino)-4-oxatricyclo[4.3.0.0[superscript 3,7]]-2-nonanone and 6,7-dimethyl-3-(2-pyridylamino)-4-oxatricyclo -[4.3.0.0[superscript 3,7]]-2-nonanone. However the diphenylphosphine group was successfully introduced at C-8 and oxidative ring-opening of the camphor skeleton has afforded the tridentate ligands, 2-(diphenylphosphinoylmethyl)-1,2-dimethyl-1,3-cyclopentanedicarboxylic acid and 2-(diphenylphosphinoylmethyl)-1,3-bis(hydroxymethyl)1,2-dimethylcyclopentane. One- and two-dimensional NMR and, where appropriate, high-resolution MS methods have been used to characterise the products. Three [superscript 13]C NMR chemical shift prediction programmes, viz., ChemWindow and the MODGRAPH neural network and HOSE (Hierachially Ordered Spherical description of Environment), have been applied to representative compounds to assess their efficacy. While the predicted shifts correlated reasonably well with the experimental data, they proved to be insufficiently accurate to differentiate the isomeric systems examined.
- Full Text:
- Date Issued: 2007
- Authors: Magqi, Nceba
- Date: 2007
- Subjects: Density functionals , Ligands , Ligands -- Design , Ligands -- Analysis , Camphor
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4358 , http://hdl.handle.net/10962/d1005023 , Density functionals , Ligands , Ligands -- Design , Ligands -- Analysis , Camphor
- Description: In this study, attention has been given to the design and synthesis of novel multidentate ligands for use in the construction of ruthenium-based metathesis catalysts, and their chelating potential has been explored by computer modelling at the Density Functional Theory (DFT) level. Both Kemp’s triacid (1,3,5-trimethyl-1,3,5-cyclohexanetricarboxylic acid) and D-(+)-camphor have been investigated as molecular scaffolds for the development of such ligands. However selective elaboration of the functional groups in Kemp’s triacid proved difficult to achieve, and the research has focused on the development of camphor derivatives. The synthesis of the camphor-based ligands has involved C-8 functionalisation and ring-opening of the bicyclic system to afford tridentate products. The formation of 9-iodocamphorquinone bis(ethylene ketal) together with the desired product, the 8-iodo isomer, has been confirmed by single crystal X-ray analysis of both compounds. Formation of the 9-iodo analogue has provided new insights into the intramolecular rearrangement of camphor skeleton, and the mechanistic implications have been assessed by coset analysis. Attempts to effect nucleophilic displacement of the 8-halogeno groups by nucleophilic donor moieties proved unexpectedly difficult and, coupled with the susceptibility of the carbonyl groups to nucleophilic attack, has led to the formation of novel tricyclic products, viz., 1,6-dimethyl-3-(2-pyridylamino)-4-oxatricyclo[4.3.0.0[superscript 3,7]]-2-nonanone and 6,7-dimethyl-3-(2-pyridylamino)-4-oxatricyclo -[4.3.0.0[superscript 3,7]]-2-nonanone. However the diphenylphosphine group was successfully introduced at C-8 and oxidative ring-opening of the camphor skeleton has afforded the tridentate ligands, 2-(diphenylphosphinoylmethyl)-1,2-dimethyl-1,3-cyclopentanedicarboxylic acid and 2-(diphenylphosphinoylmethyl)-1,3-bis(hydroxymethyl)1,2-dimethylcyclopentane. One- and two-dimensional NMR and, where appropriate, high-resolution MS methods have been used to characterise the products. Three [superscript 13]C NMR chemical shift prediction programmes, viz., ChemWindow and the MODGRAPH neural network and HOSE (Hierachially Ordered Spherical description of Environment), have been applied to representative compounds to assess their efficacy. While the predicted shifts correlated reasonably well with the experimental data, they proved to be insufficiently accurate to differentiate the isomeric systems examined.
- Full Text:
- Date Issued: 2007
Academic literacy right from the start?: a critical realist study of the way university literacy is constructed at a Gulf university
- Authors: Picard, Michelle Yvette
- Date: 2007
- Subjects: Gulf University Education, Higher -- Persian Gulf Literacy -- Persian Gulf Academic writing -- Study and teaching -- Persian Gulf English language -- Study and teaching -- Persian Gulf
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1323 , http://hdl.handle.net/10962/d1004121
- Description: The aim of this research was to examine how university literacy is constructed at a university in the Arabian Gulf and to evaluate the appropriateness of this construction where students of a low level of English are exposed to academic English (Right from the Start). Unpacking this construction is a complex task and to gain even a limited insight into the numerous Discourses, epistemologies and pedagogies constituting the construction of university literacy at Gulf universities, a stratified approach that probes the layers of ‘reality’ is necessary. Therefore, a critical realist approach is engaged, along with a variety of methods to probe the layers of the phenomenon. In terms of thesis organization, the traditional empirical structure common to the Social Sciences and the argumentative structure common to the Humanities are integrated. While the information obtained by a variety of methods is analysed and conclusions are reached, this material is also used along with additional literature to support the central contention that university literacy and academic English are possible ‘right from the start’, if the students’ literacy is examined from a certain perspective and if there is an appropriate pedagogy which promotes the desired literacies. This combination of thesis structures would be deemed appropriate in the critical realist ontological framework since the rigour of the thesis lies both in its “reliability” resulting from the empirical data and its focus on the ‘real’; and its “reflexivity” and “persuasivness” arising from the transparently ‘critical’ argument of the thesis (Cadman 2002). In order to conduct the empirical research, the lenses suggested by each of the major views of literacy as outlined by Lea and Street (1998) - namely the “study skills” view, the narrow “academic socialization view” and the “academic literacies view” are utilized in succession. However, the central argument is revealed as the manifestations of each ‘view’ of literacy in the specific context are examined, the research outcomes obtained by utilizing each view in succession are outlined and both are critiqued from the perspective of the “academic literacies” view. Corpus research is undertaken from a “study skills” perspective and the effect of the vocabulary taught to the students on their use of vocabulary in their writing is examined. Also, using the “study skills” lens, the students’ “global language development” in terms of changes or fluctuations in “fluency, accuracy and complexity” (Wolfe-Quintero, Inagaki et al. 1998) over a period of at least three semesters is examined. Utilizing a narrow “academic socialization lens”, studies conducted at the University on learning strategies and motivation and the comments made by respondents in interviews and on an electronic discussion board are compared to comments made by teachers and lecturers. Major flaws in these views of academic literacy are acknowledged and the way each view manifests itself in the Discourse(s) prevalent at this particular university is demonstrated. Finally, Discourses evidenced in the student interviews in particular, are unpacked and then compared and contrasted with those in the lecturer interviews as well as the curriculum and other university documents. The limitations of the study are examined and suggestions for further research and ways to address ‘problems’ associated with university literacy are given.
- Full Text:
- Date Issued: 2007
- Authors: Picard, Michelle Yvette
- Date: 2007
- Subjects: Gulf University Education, Higher -- Persian Gulf Literacy -- Persian Gulf Academic writing -- Study and teaching -- Persian Gulf English language -- Study and teaching -- Persian Gulf
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1323 , http://hdl.handle.net/10962/d1004121
- Description: The aim of this research was to examine how university literacy is constructed at a university in the Arabian Gulf and to evaluate the appropriateness of this construction where students of a low level of English are exposed to academic English (Right from the Start). Unpacking this construction is a complex task and to gain even a limited insight into the numerous Discourses, epistemologies and pedagogies constituting the construction of university literacy at Gulf universities, a stratified approach that probes the layers of ‘reality’ is necessary. Therefore, a critical realist approach is engaged, along with a variety of methods to probe the layers of the phenomenon. In terms of thesis organization, the traditional empirical structure common to the Social Sciences and the argumentative structure common to the Humanities are integrated. While the information obtained by a variety of methods is analysed and conclusions are reached, this material is also used along with additional literature to support the central contention that university literacy and academic English are possible ‘right from the start’, if the students’ literacy is examined from a certain perspective and if there is an appropriate pedagogy which promotes the desired literacies. This combination of thesis structures would be deemed appropriate in the critical realist ontological framework since the rigour of the thesis lies both in its “reliability” resulting from the empirical data and its focus on the ‘real’; and its “reflexivity” and “persuasivness” arising from the transparently ‘critical’ argument of the thesis (Cadman 2002). In order to conduct the empirical research, the lenses suggested by each of the major views of literacy as outlined by Lea and Street (1998) - namely the “study skills” view, the narrow “academic socialization view” and the “academic literacies view” are utilized in succession. However, the central argument is revealed as the manifestations of each ‘view’ of literacy in the specific context are examined, the research outcomes obtained by utilizing each view in succession are outlined and both are critiqued from the perspective of the “academic literacies” view. Corpus research is undertaken from a “study skills” perspective and the effect of the vocabulary taught to the students on their use of vocabulary in their writing is examined. Also, using the “study skills” lens, the students’ “global language development” in terms of changes or fluctuations in “fluency, accuracy and complexity” (Wolfe-Quintero, Inagaki et al. 1998) over a period of at least three semesters is examined. Utilizing a narrow “academic socialization lens”, studies conducted at the University on learning strategies and motivation and the comments made by respondents in interviews and on an electronic discussion board are compared to comments made by teachers and lecturers. Major flaws in these views of academic literacy are acknowledged and the way each view manifests itself in the Discourse(s) prevalent at this particular university is demonstrated. Finally, Discourses evidenced in the student interviews in particular, are unpacked and then compared and contrasted with those in the lecturer interviews as well as the curriculum and other university documents. The limitations of the study are examined and suggestions for further research and ways to address ‘problems’ associated with university literacy are given.
- Full Text:
- Date Issued: 2007
The role of ants in structuring insect communities on the canopies of senegalia drepanolobium near Laikipia, Kenya
- Authors: Kuria, Simon Kamande
- Date: 2007
- Subjects: Ants -- Kenya Ants -- Behavior Insect societies -- Kenya Forest canopy ecology -- Kenya
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5758 , http://hdl.handle.net/10962/d1005446
- Description: In the black cotton ecosystem of Laikipia, Kenya, four symbiotic ants coexist at a fine spatial scale on canopies of Senegalia drepanolobium. They exhibit different aggressive behaviours and modify their tree canopies differently. These diverse behaviours were expected to affect the associated canopy arthropod communities. At the Kenya long-term exclosure experiment (KLEE) and its immediate environs at Mpala Research Centre, Laikipia, the insect communities coexisting with each of the four ant species were characterized, and their response to different vertebrate herbivory. Other ant species inhabiting the tree canopies or the ground were surveyed too. Pitfall trapping was used in sampling terrestrial ants, while beating and mist-blowing were used in collecting arboreal insects. Different sampling methods had varying efficacies, revealing the importance of using several methods. There are at least sixteen ant species in this ecosystem, all occurring on the ground, but only ten species on the trees. Terrestrial ant communities in this ecosystem cannot be used as indicators of grazing pressure for range management. A total of 10,145 individual insects were collected from the tree canopies, comprising of 117 species from seven orders and 25 families, forming a complex community of species interacting at different levels. Symbiotic ant species had a significant effect on insect community structure and composition. Crematogaster sjostedti was associated with a community that was significantly different from the other ant species. There was no significant effect of vertebrate feeding pressure on the canopy insect community, but there was an interaction effect between ant species and treatments. Significant differences between ant species mostly occurred on treatment plots where only cows were allowed to graze. One or more of the ant species may be a keystone species in this ecosystem even though experimental manipulations failed to confirm earlier findings. It was concluded that the one-year period during which experimental manipulations were carried out was not long enough to reflect takeover effects on the insect community. The four symbiotic ant species colonizing S. drepanolobium comprises of two guilds, the hemipteran-tending ants (C. sjostedti and Crematogaster mimosae) and non-tending ants (Crematogaster nigriceps and Tetraponera penzigi). Communities associated with these guilds were found to be significantly different in all four diversity indices. The black cotton ecosystem is species-poor compared to other ecosystem such as forests. The number of insect species that colonizes S. drepanolobium and coexists with acacia-ants forms a large proportion of the invertebrate community. Therefore, this ecosystem should be conserved to safeguard this invertebrate community. This will also give scientists a chance to establish how the various insect species coexist with symbiotic ants on tree canopies.
- Full Text:
- Date Issued: 2007
- Authors: Kuria, Simon Kamande
- Date: 2007
- Subjects: Ants -- Kenya Ants -- Behavior Insect societies -- Kenya Forest canopy ecology -- Kenya
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5758 , http://hdl.handle.net/10962/d1005446
- Description: In the black cotton ecosystem of Laikipia, Kenya, four symbiotic ants coexist at a fine spatial scale on canopies of Senegalia drepanolobium. They exhibit different aggressive behaviours and modify their tree canopies differently. These diverse behaviours were expected to affect the associated canopy arthropod communities. At the Kenya long-term exclosure experiment (KLEE) and its immediate environs at Mpala Research Centre, Laikipia, the insect communities coexisting with each of the four ant species were characterized, and their response to different vertebrate herbivory. Other ant species inhabiting the tree canopies or the ground were surveyed too. Pitfall trapping was used in sampling terrestrial ants, while beating and mist-blowing were used in collecting arboreal insects. Different sampling methods had varying efficacies, revealing the importance of using several methods. There are at least sixteen ant species in this ecosystem, all occurring on the ground, but only ten species on the trees. Terrestrial ant communities in this ecosystem cannot be used as indicators of grazing pressure for range management. A total of 10,145 individual insects were collected from the tree canopies, comprising of 117 species from seven orders and 25 families, forming a complex community of species interacting at different levels. Symbiotic ant species had a significant effect on insect community structure and composition. Crematogaster sjostedti was associated with a community that was significantly different from the other ant species. There was no significant effect of vertebrate feeding pressure on the canopy insect community, but there was an interaction effect between ant species and treatments. Significant differences between ant species mostly occurred on treatment plots where only cows were allowed to graze. One or more of the ant species may be a keystone species in this ecosystem even though experimental manipulations failed to confirm earlier findings. It was concluded that the one-year period during which experimental manipulations were carried out was not long enough to reflect takeover effects on the insect community. The four symbiotic ant species colonizing S. drepanolobium comprises of two guilds, the hemipteran-tending ants (C. sjostedti and Crematogaster mimosae) and non-tending ants (Crematogaster nigriceps and Tetraponera penzigi). Communities associated with these guilds were found to be significantly different in all four diversity indices. The black cotton ecosystem is species-poor compared to other ecosystem such as forests. The number of insect species that colonizes S. drepanolobium and coexists with acacia-ants forms a large proportion of the invertebrate community. Therefore, this ecosystem should be conserved to safeguard this invertebrate community. This will also give scientists a chance to establish how the various insect species coexist with symbiotic ants on tree canopies.
- Full Text:
- Date Issued: 2007
Wheat stress responses during Russian wheat aphid and Bird Cherry Oat aphid infestation: an analysis of differential protein regulation during plant biotic stress responses
- Louw, Cassandra Alexandrovna
- Authors: Louw, Cassandra Alexandrovna
- Date: 2007
- Subjects: Russian wheat aphid , Plants, Effect of stress on , Wheat -- Diseases and pests , Rhopalosiphum , Plant proteins
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3995 , http://hdl.handle.net/10962/d1004055 , Russian wheat aphid , Plants, Effect of stress on , Wheat -- Diseases and pests , Rhopalosiphum , Plant proteins
- Description: Plants possess a complex and poorly understood network of defence mechanisms that enable them to counteract the effects of abiotic and biotic stress. Aphid phloem feeding is source of biotic stress in plants. Russian wheat aphid and Bird Cherry-Oat aphid feeding cause significant losses in the annual wheat crop, and control by conventional methods such as pesticide application, has proved to be ineffective. Infestation by the Russian wheat aphid has a particularly devastating effect in South Africa. Aphid-resistant wheat cultivars have been identified but an incomplete understanding of the mechanism of the plant’s resistance thwarts the development of improved cultivars. A two-dimensional gel electrophoresis method was developed, partially optimised and validated in order to determine the effect of Russian wheat aphid and Bird Cherry-Oat aphid phloem feeding on the Betta and Betta DN wheat proteome. Differentially expressed proteins that were up or down regulated more than two fold were identified using PDQuest™ Basic software and matched to known wheat proteins stored in the SwissProt protein database on the basis of their molecular mass and isolectric point. Initial analysis of the differential protein expression of Betta and Betta DN wheat in response to Russian wheat aphid and Bird Cherry-Oat aphid phloem feeding at different growth stages revealed that younger plants display higher levels of resistance than older plants. Feeding by the Bird-Cherry Oat aphid does not result in the upregulation of proteins implicated in a defence response, which indicates that the damage incurred by the plant due to feeding by this aphid is not enough to trigger a classic defence response. Feeding by the more damaging Russian wheat aphid resulted in a stress response in susceptible wheat cultivar Betta, and a defence response in resistant wheat cultivar Betta DN. The infestation of Betta DN resulted in the upregulation of putative thaumatins and amylase trypsin inhibitors, indicating that the Betta DN resistance response could be due to the combined effect of protease inhibitors that discourage aphid phloem feeding and the activation of the salicylic acid and jasmonic acid plant defence pathways.
- Full Text:
- Date Issued: 2007
- Authors: Louw, Cassandra Alexandrovna
- Date: 2007
- Subjects: Russian wheat aphid , Plants, Effect of stress on , Wheat -- Diseases and pests , Rhopalosiphum , Plant proteins
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3995 , http://hdl.handle.net/10962/d1004055 , Russian wheat aphid , Plants, Effect of stress on , Wheat -- Diseases and pests , Rhopalosiphum , Plant proteins
- Description: Plants possess a complex and poorly understood network of defence mechanisms that enable them to counteract the effects of abiotic and biotic stress. Aphid phloem feeding is source of biotic stress in plants. Russian wheat aphid and Bird Cherry-Oat aphid feeding cause significant losses in the annual wheat crop, and control by conventional methods such as pesticide application, has proved to be ineffective. Infestation by the Russian wheat aphid has a particularly devastating effect in South Africa. Aphid-resistant wheat cultivars have been identified but an incomplete understanding of the mechanism of the plant’s resistance thwarts the development of improved cultivars. A two-dimensional gel electrophoresis method was developed, partially optimised and validated in order to determine the effect of Russian wheat aphid and Bird Cherry-Oat aphid phloem feeding on the Betta and Betta DN wheat proteome. Differentially expressed proteins that were up or down regulated more than two fold were identified using PDQuest™ Basic software and matched to known wheat proteins stored in the SwissProt protein database on the basis of their molecular mass and isolectric point. Initial analysis of the differential protein expression of Betta and Betta DN wheat in response to Russian wheat aphid and Bird Cherry-Oat aphid phloem feeding at different growth stages revealed that younger plants display higher levels of resistance than older plants. Feeding by the Bird-Cherry Oat aphid does not result in the upregulation of proteins implicated in a defence response, which indicates that the damage incurred by the plant due to feeding by this aphid is not enough to trigger a classic defence response. Feeding by the more damaging Russian wheat aphid resulted in a stress response in susceptible wheat cultivar Betta, and a defence response in resistant wheat cultivar Betta DN. The infestation of Betta DN resulted in the upregulation of putative thaumatins and amylase trypsin inhibitors, indicating that the Betta DN resistance response could be due to the combined effect of protease inhibitors that discourage aphid phloem feeding and the activation of the salicylic acid and jasmonic acid plant defence pathways.
- Full Text:
- Date Issued: 2007
Rhodes University Orientation Week : Welcome address of the vice-chancellor of Rhodes University, Dr Saleem Badat, 5 February 2007
- Authors: Badat, Saleem
- Date: 2007
- Subjects: Rhodes University
- Language: English
- Type: text
- Identifier: vital:7651 , http://hdl.handle.net/10962/d1015779
- Full Text:
- Date Issued: 2007
- Authors: Badat, Saleem
- Date: 2007
- Subjects: Rhodes University
- Language: English
- Type: text
- Identifier: vital:7651 , http://hdl.handle.net/10962/d1015779
- Full Text:
- Date Issued: 2007
The electrochemical synthesis of 3-tert-Butyl-4-Methoxybenzaldehyde
- Authors: Qusheka, Sivuyile Emmanuel
- Date: 2007
- Subjects: Oxidation
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10410 , http://hdl.handle.net/10948/595 , Oxidation
- Description: This project was concerned with the evaluation of three potential synthetic routes for 3-tert-butyl-4-methoxybenzaldehyde, a useful fine chemical intermediate and ingredient in many sunscreen agents. The three synthetic routes all involved the selective oxidation of the 3-tert-butyl-4-methoxytoluene to the desired benzaldehyde by (a) catalytic air oxidation, (b) direct electrochemical oxidation, and (c) indirect electrochemical oxidation. In order to decide whether catalytic oxidation should precede the alkylation of 4-methoxytoluene, the selective oxidation using the well-known cobalt(II)- bromide catalyst system in acetic acid solutions were investigated with the view to determine whether increased electron density on the aromatic ring improves selectivity to the desired benzaldehyde or not. In addition, the effect of various important reaction variables was also investigated. These studies showed that increased electron density, hence increased substitution, increases the desired benzaldehyde selectivity. In addition, while reaction conditions such as reaction temperature, catalyst concentration, water concentration, etc. may be optimised for maximum 3-tert-butyl-4- methoxybenzaldehyde yields (~80 percent), such yields can only be achieved at relatively low (<40 percent) alkoxytoluene conversions. The direct electrochemical oxidation of 3-tert-butyl-4-methoxytoluene was investigated in methanol solutions containing various supporting electrolytes and using constant current electrolysis with the intention of optimizing the production of 3-tert-butyl-4-methoxybenzyl dimethyl acetal which can later be hydrolyzed using sulfuric acid to the 3-tert-butyl-4-methoxybenzaldehyde. In this study, various parameters such as supporting electrolyte and electrodes were studied. Previous studies showed undoubtedly that methanol as a solvent gave better results amongst the rest of the solvents. Indirect route was also studied as a method of synthesizing 3-tert-butyl-4- methoxybenzaldehyde and compared to the direct electro synthesis.
- Full Text:
- Date Issued: 2007
- Authors: Qusheka, Sivuyile Emmanuel
- Date: 2007
- Subjects: Oxidation
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10410 , http://hdl.handle.net/10948/595 , Oxidation
- Description: This project was concerned with the evaluation of three potential synthetic routes for 3-tert-butyl-4-methoxybenzaldehyde, a useful fine chemical intermediate and ingredient in many sunscreen agents. The three synthetic routes all involved the selective oxidation of the 3-tert-butyl-4-methoxytoluene to the desired benzaldehyde by (a) catalytic air oxidation, (b) direct electrochemical oxidation, and (c) indirect electrochemical oxidation. In order to decide whether catalytic oxidation should precede the alkylation of 4-methoxytoluene, the selective oxidation using the well-known cobalt(II)- bromide catalyst system in acetic acid solutions were investigated with the view to determine whether increased electron density on the aromatic ring improves selectivity to the desired benzaldehyde or not. In addition, the effect of various important reaction variables was also investigated. These studies showed that increased electron density, hence increased substitution, increases the desired benzaldehyde selectivity. In addition, while reaction conditions such as reaction temperature, catalyst concentration, water concentration, etc. may be optimised for maximum 3-tert-butyl-4- methoxybenzaldehyde yields (~80 percent), such yields can only be achieved at relatively low (<40 percent) alkoxytoluene conversions. The direct electrochemical oxidation of 3-tert-butyl-4-methoxytoluene was investigated in methanol solutions containing various supporting electrolytes and using constant current electrolysis with the intention of optimizing the production of 3-tert-butyl-4-methoxybenzyl dimethyl acetal which can later be hydrolyzed using sulfuric acid to the 3-tert-butyl-4-methoxybenzaldehyde. In this study, various parameters such as supporting electrolyte and electrodes were studied. Previous studies showed undoubtedly that methanol as a solvent gave better results amongst the rest of the solvents. Indirect route was also studied as a method of synthesizing 3-tert-butyl-4- methoxybenzaldehyde and compared to the direct electro synthesis.
- Full Text:
- Date Issued: 2007
The significance of participation in capacity development and project sustainability: a case study of the Zimbabwe Secondary Teacher Training Environmental Education Project (St²eep)
- Authors: Van Ongevalle, Jan
- Date: 2007
- Subjects: High school teachers -- Training of -- Zimbabwe Environmental education -- Study and teaching (secondary) -- Zimbabwe Environmental education -- Curricula -- Case studies -- Zimbabwe Environmental education -- Curricula -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1766 , http://hdl.handle.net/10962/d1003651
- Description: This study uses a systems thinking perspective to explore the role and meaning of participation, capacity development and project sustainability in the Zimbabwe Secondary Teacher Training Environmental Education Project (St²eep). Since there was no consistent critical reflection upon the different assumptions that underpin these important aspects of St²eep in the original project design, this study aims to articulate a theoretical framework for guiding the project. St2eep is a donorfunded project, located in the Ministry of Higher and Tertiary Education in Zimbabwe that seeks to integrate environmental education across the curriculum of secondary teacher education. The study first develops a theoretical framework drawing on systems thinking. In particular it uses the holistic and constructivist perspectives embedded in systems thinking to describe a number of analytic frameworks that are used as a guide to investigate participation, capacity development and project sustainability in the St²eep case study. The research methodology comprises a qualitative case study approach, which contains elements of an instrumental, evaluative and critical case study. Data-collection methods include document analysis, focus group discussions, focus group interviews, semi-structured face-to-face interviews and participant observation. Data analysis follows the constant comparative method of coding and categorising data as outlined by Strauss and Corbin (1998). The outcomes of this research show that participation processes in St²eep evolve around the interactions between a political dimension and a learning dimension. The political dimension relates to giving the project stakeholders a critical voice, allowing them to shape the project and involving them in the decision-making process. This approach has fostered an ongoing learning process in a small team of committed stakeholders based on the principles of collaborative learning, team learning and action research. Participation was shown to enhance capacity-development processes at individual and institutional level by the provision of support through learning teams, and by the renegotiation of responsibilities and power relations between lecturers involved in St²eep, donor representatives and college administrations. The strong operational role of the donor organisation was seen as a serious threat towards individual and institutional capacity development since it creates a functional but artificial and independent project system within the college system and takes over any local institutional support structure that it might seek to develop. Fostering continuous learning and capacity development, St²eep’s participatory approach was shown to contribute to a better understanding of the interconnectedness of factors that influence future sustainability of the project and the implementation of environmental education. This has assisted in the development of different scenarios on the sustainability of the project. The research shows that the project-ustainability planning process draws directly from St²eep’s ongoing learning process, with individual and institutional capacity development featuring strongly in the different scenarios, and with the external context such as the economic situation and the low priority of environmental education being recognised as important factors that need to be considered. Drawing on the findings from the case study, this study makes a tentative recommendation that donor organisations should focus more on capacity-development initiatives and avoid taking on a strong operational role in project activities. The research also recommends that there is need for a deliberate focus on both the political and learning dimensions of the participation process in order to foster local ownership. Making the learning aspect much more central in St²eep is presented as a possible strategy for motivating a larger number of college lecturers to become involved in the project and the implementation of environmental education. The study also urges St²eep to combine the different scenarios that have emerged during the project sustainability planning process and to focus on the benefits that stakeholders want to see sustained.
- Full Text:
- Date Issued: 2007
- Authors: Van Ongevalle, Jan
- Date: 2007
- Subjects: High school teachers -- Training of -- Zimbabwe Environmental education -- Study and teaching (secondary) -- Zimbabwe Environmental education -- Curricula -- Case studies -- Zimbabwe Environmental education -- Curricula -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1766 , http://hdl.handle.net/10962/d1003651
- Description: This study uses a systems thinking perspective to explore the role and meaning of participation, capacity development and project sustainability in the Zimbabwe Secondary Teacher Training Environmental Education Project (St²eep). Since there was no consistent critical reflection upon the different assumptions that underpin these important aspects of St²eep in the original project design, this study aims to articulate a theoretical framework for guiding the project. St2eep is a donorfunded project, located in the Ministry of Higher and Tertiary Education in Zimbabwe that seeks to integrate environmental education across the curriculum of secondary teacher education. The study first develops a theoretical framework drawing on systems thinking. In particular it uses the holistic and constructivist perspectives embedded in systems thinking to describe a number of analytic frameworks that are used as a guide to investigate participation, capacity development and project sustainability in the St²eep case study. The research methodology comprises a qualitative case study approach, which contains elements of an instrumental, evaluative and critical case study. Data-collection methods include document analysis, focus group discussions, focus group interviews, semi-structured face-to-face interviews and participant observation. Data analysis follows the constant comparative method of coding and categorising data as outlined by Strauss and Corbin (1998). The outcomes of this research show that participation processes in St²eep evolve around the interactions between a political dimension and a learning dimension. The political dimension relates to giving the project stakeholders a critical voice, allowing them to shape the project and involving them in the decision-making process. This approach has fostered an ongoing learning process in a small team of committed stakeholders based on the principles of collaborative learning, team learning and action research. Participation was shown to enhance capacity-development processes at individual and institutional level by the provision of support through learning teams, and by the renegotiation of responsibilities and power relations between lecturers involved in St²eep, donor representatives and college administrations. The strong operational role of the donor organisation was seen as a serious threat towards individual and institutional capacity development since it creates a functional but artificial and independent project system within the college system and takes over any local institutional support structure that it might seek to develop. Fostering continuous learning and capacity development, St²eep’s participatory approach was shown to contribute to a better understanding of the interconnectedness of factors that influence future sustainability of the project and the implementation of environmental education. This has assisted in the development of different scenarios on the sustainability of the project. The research shows that the project-ustainability planning process draws directly from St²eep’s ongoing learning process, with individual and institutional capacity development featuring strongly in the different scenarios, and with the external context such as the economic situation and the low priority of environmental education being recognised as important factors that need to be considered. Drawing on the findings from the case study, this study makes a tentative recommendation that donor organisations should focus more on capacity-development initiatives and avoid taking on a strong operational role in project activities. The research also recommends that there is need for a deliberate focus on both the political and learning dimensions of the participation process in order to foster local ownership. Making the learning aspect much more central in St²eep is presented as a possible strategy for motivating a larger number of college lecturers to become involved in the project and the implementation of environmental education. The study also urges St²eep to combine the different scenarios that have emerged during the project sustainability planning process and to focus on the benefits that stakeholders want to see sustained.
- Full Text:
- Date Issued: 2007
"Muscled Presence": Douglas Livingstone's poem "Thirteen Ways of Looking at a Black Snake"
- Authors: Everitt, M , Wylie, D
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:2262 , http://hdl.handle.net/10962/d1004642
- Description: Douglas Livingstone's poem "Thirteen Ways of Looking at a Black Snake" is an artwork which addresses precisely these questions, seeking a manner of portraying the snake which is neither grossly appropriative nor wholly detached, neither ethically empty nor preachy. In its multi-angled structure, Livingstone attempts aesthetically "to establish and embellish ... a contact zone with the nonhuman animals who share our world with us, but accepting also that there exist considerable venues on either side of this contact zone that are, on the one hand, only human, and on the other hand, only nonhuman". Even in his more formally scientific work, Livingstone argues for the inevitability of such limits to knowledge, and for the value of the imagination in addressing them.
- Full Text:
- Date Issued: 2007
- Authors: Everitt, M , Wylie, D
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:2262 , http://hdl.handle.net/10962/d1004642
- Description: Douglas Livingstone's poem "Thirteen Ways of Looking at a Black Snake" is an artwork which addresses precisely these questions, seeking a manner of portraying the snake which is neither grossly appropriative nor wholly detached, neither ethically empty nor preachy. In its multi-angled structure, Livingstone attempts aesthetically "to establish and embellish ... a contact zone with the nonhuman animals who share our world with us, but accepting also that there exist considerable venues on either side of this contact zone that are, on the one hand, only human, and on the other hand, only nonhuman". Even in his more formally scientific work, Livingstone argues for the inevitability of such limits to knowledge, and for the value of the imagination in addressing them.
- Full Text:
- Date Issued: 2007
The politics of planning in Eastern Cape local government: a case study of Ngqushwa and Buffalo City, 1998-2004
- Authors: Hollands, Glenn Delroy
- Date: 2007
- Subjects: Buffalo City (South Africa) Local government -- South Africa -- Eastern Cape -- Case studies Municipal government -- South Africa -- Eastern Cape -- Case studies Political planning -- South Africa -- Eastern Cape Eastern Cape (South Africa) -- History -- 20th century Eastern Cape (South Africa) -- History -- 21st century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2875 , http://hdl.handle.net/10962/d1008199
- Description: This thesis examines the political implications of the integrated development planning process embarked upon by South African municipalities in the period 1998-2004. Through the use of case study methodology that focuses on the Eastern Cape municipalities of Buffalo City and Ngqushwa, the conventions of municipal planning are examined. This inquiry into municipal planning draws upon official government documents and reports and publications from the nongovernment sector. The thesis is particularly focused on the claims made in policy documents and related secondary sources and compares these to more critical reports and publication as well as the author's personal experience of the integrated development planning process. Of key interest is the possibility that planning serves political interests and the material needs of an emerging municipal elite and that this is seldom acknowledged in official planning documentation or government sanctioned publications on the topic. The primary findings of the thesis are as follows: • That the 'reason' of expert policy formulations that accompanied integrated development planning has weakened political economy as a prism of understanding and separated itself from the institutional reality of municipal government • That the dominant critique of planning and other post-apartheid municipal policy is concerned with the triumph of neoliberalism but this critique, while valid, does not fully explain successive policy failures especially in the setting of Eastern Cape local government • That function of policy and its relationship to both the state and civil society is usually understood only in the most obvious sense and not as an instrument for wielding political power • That planning still derives much of its influence from its claim to technical rationality and that this underpinned the 'authority' of the integrated development planning project in South Africa and reinforced its power to make communities governable.
- Full Text:
- Date Issued: 2007
- Authors: Hollands, Glenn Delroy
- Date: 2007
- Subjects: Buffalo City (South Africa) Local government -- South Africa -- Eastern Cape -- Case studies Municipal government -- South Africa -- Eastern Cape -- Case studies Political planning -- South Africa -- Eastern Cape Eastern Cape (South Africa) -- History -- 20th century Eastern Cape (South Africa) -- History -- 21st century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2875 , http://hdl.handle.net/10962/d1008199
- Description: This thesis examines the political implications of the integrated development planning process embarked upon by South African municipalities in the period 1998-2004. Through the use of case study methodology that focuses on the Eastern Cape municipalities of Buffalo City and Ngqushwa, the conventions of municipal planning are examined. This inquiry into municipal planning draws upon official government documents and reports and publications from the nongovernment sector. The thesis is particularly focused on the claims made in policy documents and related secondary sources and compares these to more critical reports and publication as well as the author's personal experience of the integrated development planning process. Of key interest is the possibility that planning serves political interests and the material needs of an emerging municipal elite and that this is seldom acknowledged in official planning documentation or government sanctioned publications on the topic. The primary findings of the thesis are as follows: • That the 'reason' of expert policy formulations that accompanied integrated development planning has weakened political economy as a prism of understanding and separated itself from the institutional reality of municipal government • That the dominant critique of planning and other post-apartheid municipal policy is concerned with the triumph of neoliberalism but this critique, while valid, does not fully explain successive policy failures especially in the setting of Eastern Cape local government • That function of policy and its relationship to both the state and civil society is usually understood only in the most obvious sense and not as an instrument for wielding political power • That planning still derives much of its influence from its claim to technical rationality and that this underpinned the 'authority' of the integrated development planning project in South Africa and reinforced its power to make communities governable.
- Full Text:
- Date Issued: 2007
The humanities, vocationalism and the public good: exploring 'the Hamlet factor'
- Authors: Wright, Laurence
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:7028 , http://hdl.handle.net/10962/d1007214 , https://doi.org/10.1080/17535360712331393503
- Description: preprint , This paper argues that the social mission of the humanities is no longer well understood by the public, sometimes not even by the very institutions seeking to attract students to these disciplines, the universities. It becomes difficult to argue for the cogency of research in the humanities, let alone for a specific national research agenda, when the general relation between the humanities and society is widely mistaken. To address such misapprehensions, the discussion outlines as clearly as possible the characteristic procedures of the humanities, the manner in which they inform individual and social transformation, and the contemporary predicament which makes them more rather than less needed in society’s repertoire of educational resources. With this understanding in place, the paper then puts forward suggestions for strengthening research in the humanities as part of a broader programme to renovate the humanities in the South African education system.
- Full Text:
- Date Issued: 2007
- Authors: Wright, Laurence
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:7028 , http://hdl.handle.net/10962/d1007214 , https://doi.org/10.1080/17535360712331393503
- Description: preprint , This paper argues that the social mission of the humanities is no longer well understood by the public, sometimes not even by the very institutions seeking to attract students to these disciplines, the universities. It becomes difficult to argue for the cogency of research in the humanities, let alone for a specific national research agenda, when the general relation between the humanities and society is widely mistaken. To address such misapprehensions, the discussion outlines as clearly as possible the characteristic procedures of the humanities, the manner in which they inform individual and social transformation, and the contemporary predicament which makes them more rather than less needed in society’s repertoire of educational resources. With this understanding in place, the paper then puts forward suggestions for strengthening research in the humanities as part of a broader programme to renovate the humanities in the South African education system.
- Full Text:
- Date Issued: 2007
Olive Schreiner in Rhodesia: an episode in a biography
- Walters, Paul S, Fogg, W Jeremy M
- Authors: Walters, Paul S , Fogg, W Jeremy M
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6123 , http://hdl.handle.net/10962/d1004707
- Description: Readers of biographies of Olive Schreiner - except for the pioneering work of Vera Buchanan-Gould (see 1948, 198-99) - could be forgiven for doubting whether Olive Schreiner ever was in Rhodesia. Although her husband's edition of her Letters includes three which cover this journey (Cronwright-Schreiner 1924a), he makes no mention of it in his Life (1924), and it is not touched on either in First and Scott (1980) or in Stanley's impressive biographical chapter (2002). Arguably, it does nothing to alter the by now well-established outlines of Olive Schreiner's life; yet, as we shall see, the visit itself might have meant the premature end of that life. Moreover, it documents Schreiner's visit to two sites of immense importance to her : the 'Hanging Tree' in Bulawayo which features in the (deliberately shocking) photographic frontispiece to the first edition of Trooper Peter Halket of Mashonaland (1897), and, secondly, Cecil Rhodes's grave in the Matopos. In just over a decade (13 Aug. 1921), she too would lie in her chosen mountaintop tomb.
- Full Text:
- Date Issued: 2007
- Authors: Walters, Paul S , Fogg, W Jeremy M
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6123 , http://hdl.handle.net/10962/d1004707
- Description: Readers of biographies of Olive Schreiner - except for the pioneering work of Vera Buchanan-Gould (see 1948, 198-99) - could be forgiven for doubting whether Olive Schreiner ever was in Rhodesia. Although her husband's edition of her Letters includes three which cover this journey (Cronwright-Schreiner 1924a), he makes no mention of it in his Life (1924), and it is not touched on either in First and Scott (1980) or in Stanley's impressive biographical chapter (2002). Arguably, it does nothing to alter the by now well-established outlines of Olive Schreiner's life; yet, as we shall see, the visit itself might have meant the premature end of that life. Moreover, it documents Schreiner's visit to two sites of immense importance to her : the 'Hanging Tree' in Bulawayo which features in the (deliberately shocking) photographic frontispiece to the first edition of Trooper Peter Halket of Mashonaland (1897), and, secondly, Cecil Rhodes's grave in the Matopos. In just over a decade (13 Aug. 1921), she too would lie in her chosen mountaintop tomb.
- Full Text:
- Date Issued: 2007
Segregated housing and contested identities: the case of the King William's Town coloured community, 1895 - 1946
- Authors: Victor, Stephanie Emilia
- Date: 2007
- Subjects: Colored people (South Africa) -- Race identity Colored people (South Africa) -- Political activity South Africa -- Race relations Colored people (South Africa) -- Housing Housing -- South Africa -- King William's Town Colored people (South Africa) -- Relocation Colored people (South Africa) -- South Africa -- King William's Town
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2568 , http://hdl.handle.net/10962/d1002421
- Description: This thesis is a case study of the dynamics of coloured housing in King William's Town between 1895 and 1946. The impact of spatial segregation on pre-apartheid coloured settlements in the Eastern Cape has largely been ignored up to the present. This needs to be rectified as the lack of in-depth enquiry can lead to misinterpretations that may influence contemporary politics and identity formation. Through research based on primary sources, it has become apparent that segregation in King William's Town was safeguarded and rationalized through the discourses of sanitation and civilization, and the practices of relocation and removal. The existing slum cond itions were used as a convenient excuse to implement municipal control. Segregation compounded the problem of poverty, inequitable access to housing and the provision of basic services. As a result, local coloured housing was increasingly characterised by a shortage of decent accommodation and basic services, decreasing home ownership and increasing municipal tenancy. In addition, through the implementation of the 1923 Natives (Urban Areas) Act and the 1934 Slums Act, high sanitation standards were set, but the Council itself provided inferior services. Ironically, conditions in the relocated municipal settlements were also not on par with the provisions stipulated in the Slums Act that were used to effect removal in the first place. The implementation of racially exclusive housing was, therefore, not driven by a single role player. It was pioneered by the local authorities, legalised by national government and supported by the coloured elite, when needed, in an attempt to access decent housing. This occurred mainly through the political manoeuvring of the coloured elite, and specifically the African Political (later People's) Organisation (APO), the Afrikaanse Nasionale Bond (AN B) and the locally constituted Coloured Welfare Association (CWA) in King William 's Town. These organisations attempted to procure access to housing within the narrow boundaries of a prescribed identity. Segregated housing therefore fostered and sustained coloured identity. It consolidated feelings of separateness and division and provided impetus for the construction of race and even racial tension. Coloured identity attempted to serve as a rallying point to overcome differences in religion, family and social networks and place of residence in order to procure access to housing. It was not, however, able to overcome the occasional division between settlements, caused by well-developed placeidentities, which still inform the contemporary housing milieu. The coloured elite initially did not question the legitimacy of coloured identity. Only in 1939, under threats of increased residential segregation, combined with the resulting opposition in coloured protest politics, was the legitimacy of coloured identity publicly contested . By 1943, with the creation of the Coloured Advisory Council (CAC), local coloured unity proved to be insufficient. A division within the ranks of the local coloured elite was evident. As a result, the expression of coloured identity still remains contested in contemporary King William's Town.
- Full Text:
- Date Issued: 2007
- Authors: Victor, Stephanie Emilia
- Date: 2007
- Subjects: Colored people (South Africa) -- Race identity Colored people (South Africa) -- Political activity South Africa -- Race relations Colored people (South Africa) -- Housing Housing -- South Africa -- King William's Town Colored people (South Africa) -- Relocation Colored people (South Africa) -- South Africa -- King William's Town
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2568 , http://hdl.handle.net/10962/d1002421
- Description: This thesis is a case study of the dynamics of coloured housing in King William's Town between 1895 and 1946. The impact of spatial segregation on pre-apartheid coloured settlements in the Eastern Cape has largely been ignored up to the present. This needs to be rectified as the lack of in-depth enquiry can lead to misinterpretations that may influence contemporary politics and identity formation. Through research based on primary sources, it has become apparent that segregation in King William's Town was safeguarded and rationalized through the discourses of sanitation and civilization, and the practices of relocation and removal. The existing slum cond itions were used as a convenient excuse to implement municipal control. Segregation compounded the problem of poverty, inequitable access to housing and the provision of basic services. As a result, local coloured housing was increasingly characterised by a shortage of decent accommodation and basic services, decreasing home ownership and increasing municipal tenancy. In addition, through the implementation of the 1923 Natives (Urban Areas) Act and the 1934 Slums Act, high sanitation standards were set, but the Council itself provided inferior services. Ironically, conditions in the relocated municipal settlements were also not on par with the provisions stipulated in the Slums Act that were used to effect removal in the first place. The implementation of racially exclusive housing was, therefore, not driven by a single role player. It was pioneered by the local authorities, legalised by national government and supported by the coloured elite, when needed, in an attempt to access decent housing. This occurred mainly through the political manoeuvring of the coloured elite, and specifically the African Political (later People's) Organisation (APO), the Afrikaanse Nasionale Bond (AN B) and the locally constituted Coloured Welfare Association (CWA) in King William 's Town. These organisations attempted to procure access to housing within the narrow boundaries of a prescribed identity. Segregated housing therefore fostered and sustained coloured identity. It consolidated feelings of separateness and division and provided impetus for the construction of race and even racial tension. Coloured identity attempted to serve as a rallying point to overcome differences in religion, family and social networks and place of residence in order to procure access to housing. It was not, however, able to overcome the occasional division between settlements, caused by well-developed placeidentities, which still inform the contemporary housing milieu. The coloured elite initially did not question the legitimacy of coloured identity. Only in 1939, under threats of increased residential segregation, combined with the resulting opposition in coloured protest politics, was the legitimacy of coloured identity publicly contested . By 1943, with the creation of the Coloured Advisory Council (CAC), local coloured unity proved to be insufficient. A division within the ranks of the local coloured elite was evident. As a result, the expression of coloured identity still remains contested in contemporary King William's Town.
- Full Text:
- Date Issued: 2007
The impact of load and frequency on the biomechanical, physiological and perceptual responses to dynamic pushing
- Authors: Cripwell, Adam Michael
- Date: 2007
- Subjects: Work -- Physiological aspects , Psychophysiology , Human engineering , Biomechanics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5144 , http://hdl.handle.net/10962/d1008183 , Work -- Physiological aspects , Psychophysiology , Human engineering , Biomechanics
- Description: The objective of the present research was to establish the biomechanical, physiological and perceptual responses of male operators to dynamic pushing tasks. The pushing tasks were performed using an industrial pallet jack with varying load/frequency combinations, in a controlled laboratory environment. Thirty healthy male subjects comprised the sample. Experimental procedures were conducted utilising the Chatillon ™ Dynamometer to measure force output in the initial, sustained and ending phases. The K4b2 Ergospirometer was used to assess physiological responses (heart rate and oxygen consumption [V02])' Nine recorded forces and nine experimental conditions formed the basis of this study, with subjects required to push three loads (200kg, 350kg, 500kg) at three frequencies (1120 sec, 1/40 sec, 1/60 sec) at a speed of 3.6km.h-1 over 14 metres on a co-efficient of friction controlled walkway for six minutes. Gait analysis, along with perceptions of exertion (,Central ' and 'Local' RPE) were collected during the third and sixth minutes of each condition . Body discomfort and contribution were identified upon completion of each condition. The results demonstrated that load and frequency interacted to influence responses within each domain. Increasing loads required increased force output during each stage of the push, which had a concomitant effect on physiological and perceptual responses. Significant differences arose between the initial, sustained and ending forces for each load, showing the direct relationship between load and force exertion. The combination of heaviest load/quickest frequency required the greatest physiological output, exceeding recommended guidelines for heart rate, V02 and energy expenditure responses. Intermediate combinations required moderate and acceptable energy cost. Linear relationships were established between heart rate and oxygen consumption , as well as between load and V02 , thus providing industrial practitioners an opportunity to evaluate task demands in situ. The combination of high forces and elevated physiological responses increased the subjective rating of the condition. The results emphasise the need to holistically consider all contributing factors in a dynamic pushing task. Dynamic pushing tasks place biomechanical, physiological and perceptual demands on the human operator, which must be minimised in order to ensure that this form of manual materials handling becomes sustainable in the long term.
- Full Text:
- Date Issued: 2007
- Authors: Cripwell, Adam Michael
- Date: 2007
- Subjects: Work -- Physiological aspects , Psychophysiology , Human engineering , Biomechanics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5144 , http://hdl.handle.net/10962/d1008183 , Work -- Physiological aspects , Psychophysiology , Human engineering , Biomechanics
- Description: The objective of the present research was to establish the biomechanical, physiological and perceptual responses of male operators to dynamic pushing tasks. The pushing tasks were performed using an industrial pallet jack with varying load/frequency combinations, in a controlled laboratory environment. Thirty healthy male subjects comprised the sample. Experimental procedures were conducted utilising the Chatillon ™ Dynamometer to measure force output in the initial, sustained and ending phases. The K4b2 Ergospirometer was used to assess physiological responses (heart rate and oxygen consumption [V02])' Nine recorded forces and nine experimental conditions formed the basis of this study, with subjects required to push three loads (200kg, 350kg, 500kg) at three frequencies (1120 sec, 1/40 sec, 1/60 sec) at a speed of 3.6km.h-1 over 14 metres on a co-efficient of friction controlled walkway for six minutes. Gait analysis, along with perceptions of exertion (,Central ' and 'Local' RPE) were collected during the third and sixth minutes of each condition . Body discomfort and contribution were identified upon completion of each condition. The results demonstrated that load and frequency interacted to influence responses within each domain. Increasing loads required increased force output during each stage of the push, which had a concomitant effect on physiological and perceptual responses. Significant differences arose between the initial, sustained and ending forces for each load, showing the direct relationship between load and force exertion. The combination of heaviest load/quickest frequency required the greatest physiological output, exceeding recommended guidelines for heart rate, V02 and energy expenditure responses. Intermediate combinations required moderate and acceptable energy cost. Linear relationships were established between heart rate and oxygen consumption , as well as between load and V02 , thus providing industrial practitioners an opportunity to evaluate task demands in situ. The combination of high forces and elevated physiological responses increased the subjective rating of the condition. The results emphasise the need to holistically consider all contributing factors in a dynamic pushing task. Dynamic pushing tasks place biomechanical, physiological and perceptual demands on the human operator, which must be minimised in order to ensure that this form of manual materials handling becomes sustainable in the long term.
- Full Text:
- Date Issued: 2007
Antjie Krog and the accumulation of ‘media meta‐capital’:
- Authors: Garman, Anthea
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159713 , vital:40336 , DOI: 10.1080/1013929X.2007.9678272
- Description: While Krog's significant body of work in poetry, prose and journalism is undoubtedly central in her trajectory towards international renown, in this essay I explore the dynamics of her “meteoric rise in status”. The news media's role in mediating Krog to the world for nearly 40 years becomes crucial to this investigation. I use a mix of media theory and field theory to illuminate the multi‐faceted and complex relationship Krog has had with the news media and I argue that her acquisition of ‘media meta‐capital’ has played a significant role in her attainment of a unique voice and speaking platform in a postapartheid, public domain in which few white voices, and especially Afrikaner ones, are being heard.
- Full Text:
- Date Issued: 2007
- Authors: Garman, Anthea
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159713 , vital:40336 , DOI: 10.1080/1013929X.2007.9678272
- Description: While Krog's significant body of work in poetry, prose and journalism is undoubtedly central in her trajectory towards international renown, in this essay I explore the dynamics of her “meteoric rise in status”. The news media's role in mediating Krog to the world for nearly 40 years becomes crucial to this investigation. I use a mix of media theory and field theory to illuminate the multi‐faceted and complex relationship Krog has had with the news media and I argue that her acquisition of ‘media meta‐capital’ has played a significant role in her attainment of a unique voice and speaking platform in a postapartheid, public domain in which few white voices, and especially Afrikaner ones, are being heard.
- Full Text:
- Date Issued: 2007
Synthesis and photodynamic potential of tetra-and octa-triethyleneoxysulfonyl substituted zinc phthalocyanines
- Atilla, Devrim, Savdan, Nil, Durmus, Mahmut, Gürek, Ayşe Gül, Khan, Tania, Rück, Angelika, Walt, Heinrich, Nyokong, Tebello, Ahsen, Vefa
- Authors: Atilla, Devrim , Savdan, Nil , Durmus, Mahmut , Gürek, Ayşe Gül , Khan, Tania , Rück, Angelika , Walt, Heinrich , Nyokong, Tebello , Ahsen, Vefa
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281342 , vital:55715 , xlink:href="https://doi.org/10.1016/j.jphotochem.2006.08.022"
- Description: Synthesis of the water soluble zinc phthalocyanines (3, 4) obtained from the phthalonitriles substituted with oligo(ethyleneoxy)thia groups are described. The new compounds have been characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, including HSQC, HMBC and COSY bidimensional correlation techniques, electronic spectroscopy and mass spectra. The aggregation behaviour of the phthalocyanine compounds (3, 4) was investigated using UV–vis spectroscopy in dimethylsulphoxide. Photochemical and photophysical measurements were conducted on oligo(ethyleneoxy)thia appended zinc phthalocyanines. General trends are described for quantum yields of photodegredation, fluorescence yields, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds. The phototoxicity against cancer cells of the new compounds was investigated during several in vitro experiments. The dye-sensitized photooxidation of 1,3-diphenylisobenzofurane via 1O2 was studied in dimethylsulphoxide.
- Full Text:
- Date Issued: 2007
- Authors: Atilla, Devrim , Savdan, Nil , Durmus, Mahmut , Gürek, Ayşe Gül , Khan, Tania , Rück, Angelika , Walt, Heinrich , Nyokong, Tebello , Ahsen, Vefa
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281342 , vital:55715 , xlink:href="https://doi.org/10.1016/j.jphotochem.2006.08.022"
- Description: Synthesis of the water soluble zinc phthalocyanines (3, 4) obtained from the phthalonitriles substituted with oligo(ethyleneoxy)thia groups are described. The new compounds have been characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, including HSQC, HMBC and COSY bidimensional correlation techniques, electronic spectroscopy and mass spectra. The aggregation behaviour of the phthalocyanine compounds (3, 4) was investigated using UV–vis spectroscopy in dimethylsulphoxide. Photochemical and photophysical measurements were conducted on oligo(ethyleneoxy)thia appended zinc phthalocyanines. General trends are described for quantum yields of photodegredation, fluorescence yields, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds. The phototoxicity against cancer cells of the new compounds was investigated during several in vitro experiments. The dye-sensitized photooxidation of 1,3-diphenylisobenzofurane via 1O2 was studied in dimethylsulphoxide.
- Full Text:
- Date Issued: 2007