DRUBIS : a distributed face-identification experimentation framework - design, implementation and performance issues
- Authors: Ndlangisa, Mboneli
- Date: 2004
- Subjects: Principal components analysis , Human face recognition (Computer science) , Image processing , Biometric identification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4704 , http://hdl.handle.net/10962/d1015768
- Description: We report on the design, implementation and performance issues of the DRUBIS (Distributed Rhodes University Biometric Identification System) experimentation framework. The Principal Component Analysis (PCA) face-recognition approach is used as a case study. DRUBIS is a flexible experimentation framework, distributed over a number of modules that are easily pluggable and swappable, allowing for the easy construction of prototype systems. Web services are the logical means of distributing DRUBIS components and a number of prototype applications have been implemented from this framework. Different popular PCA face-recognition related experiments were used to evaluate our experimentation framework. We extract recognition performance measures from these experiments. In particular, we use the framework for a more indepth study of the suitability of the DFFS (Difference From Face Space) metric as a means for image classification in the area of race and gender determination.
- Full Text:
- Date Issued: 2004
- Authors: Ndlangisa, Mboneli
- Date: 2004
- Subjects: Principal components analysis , Human face recognition (Computer science) , Image processing , Biometric identification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4704 , http://hdl.handle.net/10962/d1015768
- Description: We report on the design, implementation and performance issues of the DRUBIS (Distributed Rhodes University Biometric Identification System) experimentation framework. The Principal Component Analysis (PCA) face-recognition approach is used as a case study. DRUBIS is a flexible experimentation framework, distributed over a number of modules that are easily pluggable and swappable, allowing for the easy construction of prototype systems. Web services are the logical means of distributing DRUBIS components and a number of prototype applications have been implemented from this framework. Different popular PCA face-recognition related experiments were used to evaluate our experimentation framework. We extract recognition performance measures from these experiments. In particular, we use the framework for a more indepth study of the suitability of the DFFS (Difference From Face Space) metric as a means for image classification in the area of race and gender determination.
- Full Text:
- Date Issued: 2004
Early development of water quality methods and approaches in ecological Reserve assessments
- Palmer, Carolyn G, Scherman, Patricia, Muller, Nikite W J, Rossouw, J N, Malan, H L, Jooste, S
- Authors: Palmer, Carolyn G , Scherman, Patricia , Muller, Nikite W J , Rossouw, J N , Malan, H L , Jooste, S
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437840 , vital:73416 , ISBN 1-77005-227-5 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/1108-1-041.pdf
- Description: This project was initiated in 2000 to allow the ecological Reserve team for water quality to undertake additional research while working on eco-logical Reserve determinations funded by the Department of Water Af-fairs and Forestry. The results of this work form the basis of the meth-ods reported in the Water Research Commission report Hughes DA (Ed)(in press).
- Full Text:
- Date Issued: 2004
- Authors: Palmer, Carolyn G , Scherman, Patricia , Muller, Nikite W J , Rossouw, J N , Malan, H L , Jooste, S
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437840 , vital:73416 , ISBN 1-77005-227-5 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/1108-1-041.pdf
- Description: This project was initiated in 2000 to allow the ecological Reserve team for water quality to undertake additional research while working on eco-logical Reserve determinations funded by the Department of Water Af-fairs and Forestry. The results of this work form the basis of the meth-ods reported in the Water Research Commission report Hughes DA (Ed)(in press).
- Full Text:
- Date Issued: 2004
Economic feasibility of an experimental octopus fishery in South Africa
- Authors: Oosthuizen, Ané
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6760 , http://hdl.handle.net/10962/d1007773
- Description: Octopus vulgaris was identified as a new marine resource to be commercially exploited through an experimental fishery. A recent policy on developing fisheries in South Africa emphasizes the importance of investigating the economic feasibility of a fishery as part of its management framework. The study reported here generated baseline information necessary in the design of the experimental fishery, giving guidelines as to which vessels, fishing gear and markets would be most feasible. The proposed fishery, gear and vessel type, fishing techniques and expected catch rates are described, the results of market research are outlined, and the cost of fishing is estimated. The potential business should consist of small and medium-sized vessels deploying unbaited pots attached to long lines. The longline pot fishery could be economically feasible, provided a 30 percent catch in 6600 pots/month is attained. Only existing, debt-free vessels should be used. The minimum catch per unit effort (CPUE) for various fishing operation scenarios was calculated to determine economic feasibility. This is an estimated minimum CPUE, based on assumptions that cannot be confirmed until the fishery starts. Furthermore, this economic analysis also needs to be assessed by stakeholders with experience of fishery operations , Rhodes Centenary issue of: South African Journal of Science.
- Full Text:
- Date Issued: 2004
- Authors: Oosthuizen, Ané
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6760 , http://hdl.handle.net/10962/d1007773
- Description: Octopus vulgaris was identified as a new marine resource to be commercially exploited through an experimental fishery. A recent policy on developing fisheries in South Africa emphasizes the importance of investigating the economic feasibility of a fishery as part of its management framework. The study reported here generated baseline information necessary in the design of the experimental fishery, giving guidelines as to which vessels, fishing gear and markets would be most feasible. The proposed fishery, gear and vessel type, fishing techniques and expected catch rates are described, the results of market research are outlined, and the cost of fishing is estimated. The potential business should consist of small and medium-sized vessels deploying unbaited pots attached to long lines. The longline pot fishery could be economically feasible, provided a 30 percent catch in 6600 pots/month is attained. Only existing, debt-free vessels should be used. The minimum catch per unit effort (CPUE) for various fishing operation scenarios was calculated to determine economic feasibility. This is an estimated minimum CPUE, based on assumptions that cannot be confirmed until the fishery starts. Furthermore, this economic analysis also needs to be assessed by stakeholders with experience of fishery operations , Rhodes Centenary issue of: South African Journal of Science.
- Full Text:
- Date Issued: 2004
Effects of substituents and solvents on the photochemical properties of zinc phthalocyanine complexes and their protonated derivatives
- Ogunsipe, Abimbola Olukayode, Nyokong, Tebello
- Authors: Ogunsipe, Abimbola Olukayode , Nyokong, Tebello
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6585 , http://hdl.handle.net/10962/d1004161
- Description: Zinc phthalocyanine derivatives containing various ring substituents and axial ligands were studied with respect to the effect of substituents on protonation. Aggregation resulted in failure of some of the ZnPc derivatives to protonate. In fact addition of protonating agents to aggregated ZnPc derivatives resulted in increase in aggregation followed by slow degradation. Axial ligands were lost on protonation. Photobleaching, fluorescence and singlet oxygen quantum yields of the protonated derivatives were compared with those of the unprotonated derivatives. In all cases protonation decreases the singlet oxygen and fluorescence quantum yields. However, photobleaching quantum yields decreased (i.e. stability increased) for the protonated derivatives except when axial ligands were present, where protonation resulted in decrease in stability.
- Full Text:
- Date Issued: 2004
- Authors: Ogunsipe, Abimbola Olukayode , Nyokong, Tebello
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6585 , http://hdl.handle.net/10962/d1004161
- Description: Zinc phthalocyanine derivatives containing various ring substituents and axial ligands were studied with respect to the effect of substituents on protonation. Aggregation resulted in failure of some of the ZnPc derivatives to protonate. In fact addition of protonating agents to aggregated ZnPc derivatives resulted in increase in aggregation followed by slow degradation. Axial ligands were lost on protonation. Photobleaching, fluorescence and singlet oxygen quantum yields of the protonated derivatives were compared with those of the unprotonated derivatives. In all cases protonation decreases the singlet oxygen and fluorescence quantum yields. However, photobleaching quantum yields decreased (i.e. stability increased) for the protonated derivatives except when axial ligands were present, where protonation resulted in decrease in stability.
- Full Text:
- Date Issued: 2004
Electrochemical and catalytic properties of chromium tetraaminophthalocyanine
- Obirai, Joe, Nyokong, Tebello
- Authors: Obirai, Joe , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300310 , vital:57915 , xlink:href="https://doi.org/10.1016/j.jelechem.2004.06.026"
- Description: Chromium tetraaminophthalocyanine (CrIIITAPc) has been synthesized and its electrochemical and spectroelectrochemical properties reported. The first reduction and oxidation in this complex occur at the central metal, giving CrIITAPc and CrIVTAPc complexes, respectively, the latter having been observed for the first time. The CrIIITAPc species was polymerized onto glassy carbon (GCE) or indium tin oxide (ITO) electrodes and the polymer evolution confirmed by UV/Visible spectroscopy and by scanning electron microscopy. The polymers were employed for the catalytic oxidation of nitrite or nitric oxide, and the catalysis involved the CrIVTAPc−1 species.
- Full Text:
- Date Issued: 2004
- Authors: Obirai, Joe , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300310 , vital:57915 , xlink:href="https://doi.org/10.1016/j.jelechem.2004.06.026"
- Description: Chromium tetraaminophthalocyanine (CrIIITAPc) has been synthesized and its electrochemical and spectroelectrochemical properties reported. The first reduction and oxidation in this complex occur at the central metal, giving CrIITAPc and CrIVTAPc complexes, respectively, the latter having been observed for the first time. The CrIIITAPc species was polymerized onto glassy carbon (GCE) or indium tin oxide (ITO) electrodes and the polymer evolution confirmed by UV/Visible spectroscopy and by scanning electron microscopy. The polymers were employed for the catalytic oxidation of nitrite or nitric oxide, and the catalysis involved the CrIVTAPc−1 species.
- Full Text:
- Date Issued: 2004
Electrochemical investigation of valve regulated lead acid batteries
- Authors: Ferg, Ernst Eduard
- Date: 2004
- Subjects: Lead acid batteries -- South Africa , Storage batteries -- South Africa , Electrochemistry -- South Africa
- Language: English
- Type: Thesis , Doctoral , DTech (Chemistry)
- Identifier: vital:10979 , http://hdl.handle.net/10948/228 , Lead acid batteries -- South Africa , Storage batteries -- South Africa , Electrochemistry -- South Africa
- Description: One of the technical advances made by the lead-acid battery industry in the field of portable power supply was the development of the valve regulated lead-acid battery (VRLA). This battery reduced the necessity for periodic servicing in terms of having to replenish the cells with distilled water. Further, this new type of battery can now be installed near sensitive electronic equipment without the danger of acid spill or dangerous fumes being emitted. In addition, longer service performance is achieved in terms of life cycle capacity, when compared to the conventional flooded type batteries. However, the new type of battery requires the manufacturing of high precision electrodes and components with low tolerances for error. In order for the manufacturers to produce such a premium product, a thorough understanding of the electrochemistry of the inner components is necessary. None of the South African lead-acid battery manufacturers are currently making VRLA batteries to supply a very competitive global market, where a large range of sizes and capabilities are available. In order to introduce the VRLA battery into such a competing market in South Africa, a niche area for its application was identified in order to establish the viability of manufacturing such a battery locally. This is done by integrating the VRLA concept into an existing battery, such as the miners cap lamp (MCL) battery. Its application is specific with well-defined performance criteria in a relatively large consumable market in the South African mining industry. The study looked at various components within a local manufacturing environment that required a better understanding and modification of the processes to build VRLA MCL batteries. This included a detailed study of the manufacturing processes of the positive electrode. The study involved the investigation of the types of grid alloys used, the type of electrode design, such as tubular or flat plate, the addition of redlead to the paste mixing process and subjecting the batteries to accelerated life cycle testing. A better understanding of the oxygen recombination cycle was also performed in order to evaluate the correct use of certain design criteria in the manufacturing process. This included the study of the pressure release valve and the type of positive electrode used. The study also looked at developing an inexpensive analytical technique to evaluate the porosity of cured and formed electrodes using a glycerol displacement method. The monitoring of the state of health (SoH) of VRLA batteries on a continuous basis is an important parameter in unique applications such as remote power supply. A device was developed to monitor the SoH of VRLA batteries on a continuous basis. The working principle of the device was tested on a MCL VRLA battery. With the development of other types of VRLA batteries for specific applications such as in stand-by power supplies, the monitoring device would then be integrated in the battery design.
- Full Text:
- Date Issued: 2004
- Authors: Ferg, Ernst Eduard
- Date: 2004
- Subjects: Lead acid batteries -- South Africa , Storage batteries -- South Africa , Electrochemistry -- South Africa
- Language: English
- Type: Thesis , Doctoral , DTech (Chemistry)
- Identifier: vital:10979 , http://hdl.handle.net/10948/228 , Lead acid batteries -- South Africa , Storage batteries -- South Africa , Electrochemistry -- South Africa
- Description: One of the technical advances made by the lead-acid battery industry in the field of portable power supply was the development of the valve regulated lead-acid battery (VRLA). This battery reduced the necessity for periodic servicing in terms of having to replenish the cells with distilled water. Further, this new type of battery can now be installed near sensitive electronic equipment without the danger of acid spill or dangerous fumes being emitted. In addition, longer service performance is achieved in terms of life cycle capacity, when compared to the conventional flooded type batteries. However, the new type of battery requires the manufacturing of high precision electrodes and components with low tolerances for error. In order for the manufacturers to produce such a premium product, a thorough understanding of the electrochemistry of the inner components is necessary. None of the South African lead-acid battery manufacturers are currently making VRLA batteries to supply a very competitive global market, where a large range of sizes and capabilities are available. In order to introduce the VRLA battery into such a competing market in South Africa, a niche area for its application was identified in order to establish the viability of manufacturing such a battery locally. This is done by integrating the VRLA concept into an existing battery, such as the miners cap lamp (MCL) battery. Its application is specific with well-defined performance criteria in a relatively large consumable market in the South African mining industry. The study looked at various components within a local manufacturing environment that required a better understanding and modification of the processes to build VRLA MCL batteries. This included a detailed study of the manufacturing processes of the positive electrode. The study involved the investigation of the types of grid alloys used, the type of electrode design, such as tubular or flat plate, the addition of redlead to the paste mixing process and subjecting the batteries to accelerated life cycle testing. A better understanding of the oxygen recombination cycle was also performed in order to evaluate the correct use of certain design criteria in the manufacturing process. This included the study of the pressure release valve and the type of positive electrode used. The study also looked at developing an inexpensive analytical technique to evaluate the porosity of cured and formed electrodes using a glycerol displacement method. The monitoring of the state of health (SoH) of VRLA batteries on a continuous basis is an important parameter in unique applications such as remote power supply. A device was developed to monitor the SoH of VRLA batteries on a continuous basis. The working principle of the device was tested on a MCL VRLA battery. With the development of other types of VRLA batteries for specific applications such as in stand-by power supplies, the monitoring device would then be integrated in the battery design.
- Full Text:
- Date Issued: 2004
Electrochemical studies of manganese tetraamminophthalocyanine monomer and polymer
- Obirai, Joseph, Nyokong, Tebello
- Authors: Obirai, Joseph , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290330 , vital:56738 , xlink:href="https://doi.org/10.1016/j.electacta.2003.11.006"
- Description: Manganese tetraaminophthalocyanine (MnTAPc) has been synthesised. The cyclic voltammetry and spectroelectrochemistry of the complex have been examined. Spectroelectrochemistry has been used to confirm that the species synthesised in this work contains MnIII, giving (OH)MnIIITAPc. The oxidation and reduction couples obtained from cyclic voltammetry have been assigned to MnIVPc−/MnIVPc2− (couple I), MnIVPc2−/MnIIIPc2− (couple I′), MnIIIPc2−/MnIIPc2− (couple II) and MnIIPc2−/MnIIPc3− (couple III). Electropolymerization of the MnTAPc onto either the indium tin oxide or glassy carbon electrode results in the in the formation of a poly-MnTAPc. The poly-MnTAPc shows improved reversibility at low pH. The poly-MnTAPc electrode was employed to analyse glycine.
- Full Text:
- Date Issued: 2004
- Authors: Obirai, Joseph , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290330 , vital:56738 , xlink:href="https://doi.org/10.1016/j.electacta.2003.11.006"
- Description: Manganese tetraaminophthalocyanine (MnTAPc) has been synthesised. The cyclic voltammetry and spectroelectrochemistry of the complex have been examined. Spectroelectrochemistry has been used to confirm that the species synthesised in this work contains MnIII, giving (OH)MnIIITAPc. The oxidation and reduction couples obtained from cyclic voltammetry have been assigned to MnIVPc−/MnIVPc2− (couple I), MnIVPc2−/MnIIIPc2− (couple I′), MnIIIPc2−/MnIIPc2− (couple II) and MnIIPc2−/MnIIPc3− (couple III). Electropolymerization of the MnTAPc onto either the indium tin oxide or glassy carbon electrode results in the in the formation of a poly-MnTAPc. The poly-MnTAPc shows improved reversibility at low pH. The poly-MnTAPc electrode was employed to analyse glycine.
- Full Text:
- Date Issued: 2004
Emerging patterns of abstraction in environmental education: A review of materials, methods and professional development perspectives
- O'Donoghue, Rob B, Russo, Vladimir
- Authors: O'Donoghue, Rob B , Russo, Vladimir
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/373610 , vital:66707 , xlink:href="https://doi.org/10.1080/1350462042000258170"
- Description: The epistemic unconscious is the history of the field. And it is clear that, to secure some chance of really knowing what one is doing, one has to unfold what is inscribed in the various relations of implication in which the thinker and his thoughts are caught up, that is, the presuppositions he engages and the inclusions and exclusions he unwittingly performs. (Bourdieu, 2000, p. 99).
- Full Text:
- Date Issued: 2004
- Authors: O'Donoghue, Rob B , Russo, Vladimir
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/373610 , vital:66707 , xlink:href="https://doi.org/10.1080/1350462042000258170"
- Description: The epistemic unconscious is the history of the field. And it is clear that, to secure some chance of really knowing what one is doing, one has to unfold what is inscribed in the various relations of implication in which the thinker and his thoughts are caught up, that is, the presuppositions he engages and the inclusions and exclusions he unwittingly performs. (Bourdieu, 2000, p. 99).
- Full Text:
- Date Issued: 2004
Emotions, social transformation and education
- Authors: Delport, Aletta Catherine
- Date: 2004
- Subjects: Educational sociology -- South Africa , Education -- Philosophy , Emotions (Philosophy)
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:11009 , http://hdl.handle.net/10948/318 , Educational sociology -- South Africa , Education -- Philosophy , Emotions (Philosophy)
- Description: This thesis addresses the topic of the education of the emotions in the context of a rapidly transforming South African society. It attempts to reconfigure the conceptual landscape in terms of which we think about rationality, social transformation and education, and contests the intellectual and instrumental prejudice in the currently dominant ways of thinking about education. It reclaims a sense of what it would be to think of education in terms of cultivating humanity, as a key to the profound transformation of the South African society. It argues that the emotions should be relocated in our conception of transformation and education, because without it, education will fail to assist South African society to transform into a society where most people are able to live improved quality lives. The thesis comprises three distinct parts. The first part consists of an account of a particular cognitive theory of the emotions, as developed by Martha Nussbaum in her book, Upheavals of thought. The Intelligence of Emotions (2001). This theory is then applied in Part 2 to examine the complexities of social transformation in South Africa at the more profound, personal level. This investigation is presented as a narrative and comprises the perspectives of the author, who is a white Afrikaner female, who grew up in South Africa in the heyday of Apartheid. In the final part, the concept of ‘education for transformation’ is discussed. It is argued that, in order for education to enhance the social transformation of South Africa, social transformation should be conceived according to a fundamental aspect of Rousseau’s political philosophy, namely that the ideal society comprises two reciprocally related spheres, the political and the personal sphere. Part 3 argues that ‘education for transformation’ should be conceived according to a conception of transformation, which acknowledges this double-layered texture. It further argues that ‘education for transformation’ should primarily be concerned with transformation at the personal level, since, according to Rousseau’s philosophy, this dimension is fundamental to ensuring the stability and legitimacy of the political order. However, built on the main insights of Part 2, this thesis also argues that personal transformation is only possible within a framework of rationality, which acknowledges the emotions as constitutive elements of rationality itself. Essentially, this thesis is about the conception of human being, which should be esteemed as the most fundamental and crucial element of successful social transformation.
- Full Text:
- Date Issued: 2004
- Authors: Delport, Aletta Catherine
- Date: 2004
- Subjects: Educational sociology -- South Africa , Education -- Philosophy , Emotions (Philosophy)
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:11009 , http://hdl.handle.net/10948/318 , Educational sociology -- South Africa , Education -- Philosophy , Emotions (Philosophy)
- Description: This thesis addresses the topic of the education of the emotions in the context of a rapidly transforming South African society. It attempts to reconfigure the conceptual landscape in terms of which we think about rationality, social transformation and education, and contests the intellectual and instrumental prejudice in the currently dominant ways of thinking about education. It reclaims a sense of what it would be to think of education in terms of cultivating humanity, as a key to the profound transformation of the South African society. It argues that the emotions should be relocated in our conception of transformation and education, because without it, education will fail to assist South African society to transform into a society where most people are able to live improved quality lives. The thesis comprises three distinct parts. The first part consists of an account of a particular cognitive theory of the emotions, as developed by Martha Nussbaum in her book, Upheavals of thought. The Intelligence of Emotions (2001). This theory is then applied in Part 2 to examine the complexities of social transformation in South Africa at the more profound, personal level. This investigation is presented as a narrative and comprises the perspectives of the author, who is a white Afrikaner female, who grew up in South Africa in the heyday of Apartheid. In the final part, the concept of ‘education for transformation’ is discussed. It is argued that, in order for education to enhance the social transformation of South Africa, social transformation should be conceived according to a fundamental aspect of Rousseau’s political philosophy, namely that the ideal society comprises two reciprocally related spheres, the political and the personal sphere. Part 3 argues that ‘education for transformation’ should be conceived according to a conception of transformation, which acknowledges this double-layered texture. It further argues that ‘education for transformation’ should primarily be concerned with transformation at the personal level, since, according to Rousseau’s philosophy, this dimension is fundamental to ensuring the stability and legitimacy of the political order. However, built on the main insights of Part 2, this thesis also argues that personal transformation is only possible within a framework of rationality, which acknowledges the emotions as constitutive elements of rationality itself. Essentially, this thesis is about the conception of human being, which should be esteemed as the most fundamental and crucial element of successful social transformation.
- Full Text:
- Date Issued: 2004
Endothermy in African Platypleurine Cicadas: the influence of body size and habitat (Hemiptera: Cicadidae)
- Sanborn, Allen F, Villet, Martin H, Phillips, Polly K F
- Authors: Sanborn, Allen F , Villet, Martin H , Phillips, Polly K F
- Date: 2004
- Language: English
- Type: text , Article
- Identifier: vital:6925 , http://hdl.handle.net/10962/d1011912
- Description: The platypleurine cicadas have a wide distribution across Africa and southern Asia. We investigate endothermy as a thermoregulatory strategy in 11 South African species from five genera, with comparisons to the lone ectothermic platypleurine we found, in an attempt to ascertain any influence that habitat and/or body size have on the expression of endothermy in the platypleurine cicadas. Field measurements of body temperature (Tb) show that these animals regulate Tb through endogenous heat production. Heat production in the laboratory elevated Tb to the same range as in animals active in the field. Maximum Tb measured during calling activity when there was no access to solar radiation ranged from 13.2° to 22.3°C above ambient temperature in the five species measured. The mean Tb during activity without access to solar radiation did not differ from the mean Tb during diurnal activity. All platypleurines exhibit a unique behavior for cicadas while warming endogenously, a temperature- dependent telescoping pulsation of the abdomen that probably functions in ventilation. Platypleurines generally call from trunks and branches within the canopy and appear to rely on endothermy even when the sun is available to elevate Tb, in contrast to the facultative endothermy exhibited by New World endothermic species. The two exceptions to this generalization we found within the platypleurines are Platypleura wahlbergi and Albanycada albigera, which were the smallest species studied. The small size of P. wahlbergi appears to have altered their thermoregulatory strategy to one of facultative endothermy, whereby they use the sun when it is available to facilitate increases in Tb. Albanycada albigera is the only ectothermic platypleurine we found. The habitat and host plant association of A. albigera appear to have influenced the choice of ectothermy as a thermoregulatory strategy, as the species possesses the metabolic machinery to elevate to the Tb range observed in the endothermic species. Therefore, size and habitat appear to influence the expression of thermoregulatory strategies in African platypleurine cicadas.
- Full Text:
- Date Issued: 2004
- Authors: Sanborn, Allen F , Villet, Martin H , Phillips, Polly K F
- Date: 2004
- Language: English
- Type: text , Article
- Identifier: vital:6925 , http://hdl.handle.net/10962/d1011912
- Description: The platypleurine cicadas have a wide distribution across Africa and southern Asia. We investigate endothermy as a thermoregulatory strategy in 11 South African species from five genera, with comparisons to the lone ectothermic platypleurine we found, in an attempt to ascertain any influence that habitat and/or body size have on the expression of endothermy in the platypleurine cicadas. Field measurements of body temperature (Tb) show that these animals regulate Tb through endogenous heat production. Heat production in the laboratory elevated Tb to the same range as in animals active in the field. Maximum Tb measured during calling activity when there was no access to solar radiation ranged from 13.2° to 22.3°C above ambient temperature in the five species measured. The mean Tb during activity without access to solar radiation did not differ from the mean Tb during diurnal activity. All platypleurines exhibit a unique behavior for cicadas while warming endogenously, a temperature- dependent telescoping pulsation of the abdomen that probably functions in ventilation. Platypleurines generally call from trunks and branches within the canopy and appear to rely on endothermy even when the sun is available to elevate Tb, in contrast to the facultative endothermy exhibited by New World endothermic species. The two exceptions to this generalization we found within the platypleurines are Platypleura wahlbergi and Albanycada albigera, which were the smallest species studied. The small size of P. wahlbergi appears to have altered their thermoregulatory strategy to one of facultative endothermy, whereby they use the sun when it is available to facilitate increases in Tb. Albanycada albigera is the only ectothermic platypleurine we found. The habitat and host plant association of A. albigera appear to have influenced the choice of ectothermy as a thermoregulatory strategy, as the species possesses the metabolic machinery to elevate to the Tb range observed in the endothermic species. Therefore, size and habitat appear to influence the expression of thermoregulatory strategies in African platypleurine cicadas.
- Full Text:
- Date Issued: 2004
English language teaching and learning in the African preschool and educational achievement at grade 1: a case study
- Authors: Rendel, Philip Boudewijn
- Date: 2004
- Subjects: Education, Preschool -- South Africa -- Case studies , English language -- Study and teaching (Preschool) -- South Africa Case studies , English language -- Study and teaching (Elementary) -- South Africa -- Case studies , Children -- South Africa -- Language -- Case studies , Language acquisition -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2360 , http://hdl.handle.net/10962/d1002643 , Education, Preschool -- South Africa -- Case studies , English language -- Study and teaching (Preschool) -- South Africa Case studies , English language -- Study and teaching (Elementary) -- South Africa -- Case studies , Children -- South Africa -- Language -- Case studies , Language acquisition -- Case studies
- Description: In 1998, seventy per cent of children in South Africa failed and had to repeat the Grade 1 year. This is the result of a number of factors, among them academic and cultural readiness for school. Many primary schools in South Africa teach through English, a language that is not the home language of the majority of learners. Despite recent legislation aimed at improving preschool facilities and teacher capacity, there has been insufficient consideration of which languages are taught and how they should be taught to children before they arrive at Grade 1. This study sets out to explore whether there is a relational link between preschool English language teaching and learning and subsequent educational achievement at Grade 1. It also sketches out possible recommendations for improving the teaching and learning of English in the sample schools. The study does not attempt to enter the debate over choice of language of teaching and learning (LoLT). In this longitudinal case study, four children from two different preschools, (one mainly isiXhosa medium and one English medium), were observed in their classroom environments over a period of four months. The following year, the same children were observed in their respective Grade 1 classrooms, all of which were English medium either entirely or to a degree. The parents of all four children were interviewed in their home environment, as were their teachers. The study found that there is a significant communication gap between preschool teachers and Grade 1 teachers. This was combined with a self-confessed need amongst some teachers for increased training in teaching through English. Low motivation and limited professional experience in some cases contributed to a preschool language-learning environment that lacked many of the factors identified as being essential for a positive learning environment in early childhood There was in addition a clear bias in many sites towards universality of ECD prinCiples with little regard for the hegemony of Western pedagogy, particularly in the area of literacy acquisition. The study concludes by suggesting some ways in which this situation could be improved in order to enable preschool children to cope better with the demands of Grade 1.
- Full Text:
- Date Issued: 2004
- Authors: Rendel, Philip Boudewijn
- Date: 2004
- Subjects: Education, Preschool -- South Africa -- Case studies , English language -- Study and teaching (Preschool) -- South Africa Case studies , English language -- Study and teaching (Elementary) -- South Africa -- Case studies , Children -- South Africa -- Language -- Case studies , Language acquisition -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2360 , http://hdl.handle.net/10962/d1002643 , Education, Preschool -- South Africa -- Case studies , English language -- Study and teaching (Preschool) -- South Africa Case studies , English language -- Study and teaching (Elementary) -- South Africa -- Case studies , Children -- South Africa -- Language -- Case studies , Language acquisition -- Case studies
- Description: In 1998, seventy per cent of children in South Africa failed and had to repeat the Grade 1 year. This is the result of a number of factors, among them academic and cultural readiness for school. Many primary schools in South Africa teach through English, a language that is not the home language of the majority of learners. Despite recent legislation aimed at improving preschool facilities and teacher capacity, there has been insufficient consideration of which languages are taught and how they should be taught to children before they arrive at Grade 1. This study sets out to explore whether there is a relational link between preschool English language teaching and learning and subsequent educational achievement at Grade 1. It also sketches out possible recommendations for improving the teaching and learning of English in the sample schools. The study does not attempt to enter the debate over choice of language of teaching and learning (LoLT). In this longitudinal case study, four children from two different preschools, (one mainly isiXhosa medium and one English medium), were observed in their classroom environments over a period of four months. The following year, the same children were observed in their respective Grade 1 classrooms, all of which were English medium either entirely or to a degree. The parents of all four children were interviewed in their home environment, as were their teachers. The study found that there is a significant communication gap between preschool teachers and Grade 1 teachers. This was combined with a self-confessed need amongst some teachers for increased training in teaching through English. Low motivation and limited professional experience in some cases contributed to a preschool language-learning environment that lacked many of the factors identified as being essential for a positive learning environment in early childhood There was in addition a clear bias in many sites towards universality of ECD prinCiples with little regard for the hegemony of Western pedagogy, particularly in the area of literacy acquisition. The study concludes by suggesting some ways in which this situation could be improved in order to enable preschool children to cope better with the demands of Grade 1.
- Full Text:
- Date Issued: 2004
Environmental education research and social change: Southern African perspectives
- Authors: Lotz-Sisitka, Heila
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182709 , vital:43855 , xlink:href="https://doi.org/10.1080/1350462042000258143"
- Description: Environmental issues and risks in southern Africa have, like elsewhere in the world, their roots in the structures and orientations of modern societies. In modernist fashion, we draw on education and research to address socio-ecological concerns. In 1995 Eureta Janse van Rensburg, then Murray and Roberts Chair of Environmental Education at Rhodes University,1 undertook a study to identify environmental education research priorities, and through her study she provided a description of research in environmental education as a ‘landscape of shifting priorites’ (Janse van Rensburg, 1995). The papers in this journal offer a contemporary ‘snapshot’ of the landscape of environmental education research in southern Africa, illustrating a fresh range of ‘shifting priorities’.
- Full Text:
- Date Issued: 2004
- Authors: Lotz-Sisitka, Heila
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182709 , vital:43855 , xlink:href="https://doi.org/10.1080/1350462042000258143"
- Description: Environmental issues and risks in southern Africa have, like elsewhere in the world, their roots in the structures and orientations of modern societies. In modernist fashion, we draw on education and research to address socio-ecological concerns. In 1995 Eureta Janse van Rensburg, then Murray and Roberts Chair of Environmental Education at Rhodes University,1 undertook a study to identify environmental education research priorities, and through her study she provided a description of research in environmental education as a ‘landscape of shifting priorites’ (Janse van Rensburg, 1995). The papers in this journal offer a contemporary ‘snapshot’ of the landscape of environmental education research in southern Africa, illustrating a fresh range of ‘shifting priorities’.
- Full Text:
- Date Issued: 2004
Environmental water quality in water resources management
- Palmer, Carolyn G, Berold, Robert, Muller, Nikite W J
- Authors: Palmer, Carolyn G , Berold, Robert , Muller, Nikite W J
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437611 , vital:73397 , ISBN 1-77005-083-3 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/TT217-04.pdf
- Description: This book will help anyone working with water resources to make decisions about water quality, specifically environmental aspects of water quality. The book ex-plores the balance between water resource protection and water resource use, with a particular focus on water quality. A balance is necessary because the National Wa-ter Act (NWA) requires that water resources be protected and managed to meet the water quality requirements of ecosystems. At the same time the Act also requires that water be used for social and economic benefit.
- Full Text:
- Date Issued: 2004
- Authors: Palmer, Carolyn G , Berold, Robert , Muller, Nikite W J
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437611 , vital:73397 , ISBN 1-77005-083-3 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/TT217-04.pdf
- Description: This book will help anyone working with water resources to make decisions about water quality, specifically environmental aspects of water quality. The book ex-plores the balance between water resource protection and water resource use, with a particular focus on water quality. A balance is necessary because the National Wa-ter Act (NWA) requires that water resources be protected and managed to meet the water quality requirements of ecosystems. At the same time the Act also requires that water be used for social and economic benefit.
- Full Text:
- Date Issued: 2004
Equity in the South African legal system a critical ethnography
- Authors: Leiper, Jonathan
- Date: 2004
- Subjects: Court interpreting and translating -- South Africa , Language and languages -- Law and legislation -- South Africa , Translators -- Training of -- South Africa , Translators -- Legal status, laws, etc. -- South Africa , Law -- Translating -- South Africa , Law -- South Africa -- Language
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2355 , http://hdl.handle.net/10962/d1002637 , Court interpreting and translating -- South Africa , Language and languages -- Law and legislation -- South Africa , Translators -- Training of -- South Africa , Translators -- Legal status, laws, etc. -- South Africa , Law -- Translating -- South Africa , Law -- South Africa -- Language
- Description: This thesis focuses on the process of interpreting and the difficulties faced by interpreters in the Magistrates' Court in Grahamstown, South Africa. More particularly, the thesis seeks to establish whether the constitutional guarantee of language equity can be applied to the courts - given the numerous problems with interpreting. Respondents from different spheres of the legal profession were interviewed in order to ascertain their perspectives on the state of interpreting, problems that are encountered by interpreters and attitudes displayed by other members of the legal profession towards interpreters. The methodology used in the thesis is that of a critical ethnography. As such, the research also has a critical focus, seeking to determine the ideologies and interests of different ):articipants in the legal process. On the basis of the data collected, a number of conclusions are drawn. The first is that interpreting in South Africa is in trouble. The system of interpreting is beset by a number of different problems. This study describes four different types of problems that are faced by interpreters: linguistic problems, environmental problems, training and administrative issues, and poor status in the eyes of the other participants in the legal process. Together the cumulative effect of these problems is the undermining of the principle of equity in the justice system. Finally, the thesis provides various practical and achievable solutions to the problems outlined above, specifically those faced by interpreters. The researcher also critically evaluates the efforts and motives of the Department of Justice and Constitutional Development.
- Full Text:
- Date Issued: 2004
- Authors: Leiper, Jonathan
- Date: 2004
- Subjects: Court interpreting and translating -- South Africa , Language and languages -- Law and legislation -- South Africa , Translators -- Training of -- South Africa , Translators -- Legal status, laws, etc. -- South Africa , Law -- Translating -- South Africa , Law -- South Africa -- Language
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2355 , http://hdl.handle.net/10962/d1002637 , Court interpreting and translating -- South Africa , Language and languages -- Law and legislation -- South Africa , Translators -- Training of -- South Africa , Translators -- Legal status, laws, etc. -- South Africa , Law -- Translating -- South Africa , Law -- South Africa -- Language
- Description: This thesis focuses on the process of interpreting and the difficulties faced by interpreters in the Magistrates' Court in Grahamstown, South Africa. More particularly, the thesis seeks to establish whether the constitutional guarantee of language equity can be applied to the courts - given the numerous problems with interpreting. Respondents from different spheres of the legal profession were interviewed in order to ascertain their perspectives on the state of interpreting, problems that are encountered by interpreters and attitudes displayed by other members of the legal profession towards interpreters. The methodology used in the thesis is that of a critical ethnography. As such, the research also has a critical focus, seeking to determine the ideologies and interests of different ):articipants in the legal process. On the basis of the data collected, a number of conclusions are drawn. The first is that interpreting in South Africa is in trouble. The system of interpreting is beset by a number of different problems. This study describes four different types of problems that are faced by interpreters: linguistic problems, environmental problems, training and administrative issues, and poor status in the eyes of the other participants in the legal process. Together the cumulative effect of these problems is the undermining of the principle of equity in the justice system. Finally, the thesis provides various practical and achievable solutions to the problems outlined above, specifically those faced by interpreters. The researcher also critically evaluates the efforts and motives of the Department of Justice and Constitutional Development.
- Full Text:
- Date Issued: 2004
Evaluating the district office budgeting process of the Department of Education in terms of the Batho Pele principles
- Authors: Gorgonzola, Ernest
- Date: 2004
- Subjects: South Africa. Dept. of Education -- Appropriations and expenditures , Budget -- South Africa , Education -- South Africa -- Finance
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10926 , http://hdl.handle.net/10948/165 , South Africa. Dept. of Education -- Appropriations and expenditures , Budget -- South Africa , Education -- South Africa -- Finance
- Description: The objective of this research was to evaluate the district office budgeting process of the Department of Education, Port Elizabeth District, in terms of the Batho Pele principles. The aim of district offices is to satisfy the most basic education needs of people in their respective areas of jurisdiction. Improving service delivery is one of government’s eight priorities as set out in the White Paper on the transformation of the Public Service (South African Government, 1995: 4). The initiative to improve service delivery is called Batho Pele. The main research question to be addressed by this research is: Does the Department of Education experience any problems with its budgeting process to address service delivery? Through a literature survey and empirical study, various conclusions were reached and recommendations made. The bulk of education expenditure takes place within education districts but the controlling, forecasting and budgeting of expenditure takes place at the Provincial Head Office. Most high schools surveyed experience problems with the current funding policy of the Department of Education. The relative poverty of the community around the school impacts negatively on the parent’s ability to support the school. iv The budgeting process of the Department of Education should follow a bottom-up approach to budgeting. Therefore, the district office budget should be informed by the needs of the school and the provincial budget be informed by the district office budget. The management and administrative capacity at the district office need to be developed to ensure effective budgeting.
- Full Text:
- Date Issued: 2004
- Authors: Gorgonzola, Ernest
- Date: 2004
- Subjects: South Africa. Dept. of Education -- Appropriations and expenditures , Budget -- South Africa , Education -- South Africa -- Finance
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10926 , http://hdl.handle.net/10948/165 , South Africa. Dept. of Education -- Appropriations and expenditures , Budget -- South Africa , Education -- South Africa -- Finance
- Description: The objective of this research was to evaluate the district office budgeting process of the Department of Education, Port Elizabeth District, in terms of the Batho Pele principles. The aim of district offices is to satisfy the most basic education needs of people in their respective areas of jurisdiction. Improving service delivery is one of government’s eight priorities as set out in the White Paper on the transformation of the Public Service (South African Government, 1995: 4). The initiative to improve service delivery is called Batho Pele. The main research question to be addressed by this research is: Does the Department of Education experience any problems with its budgeting process to address service delivery? Through a literature survey and empirical study, various conclusions were reached and recommendations made. The bulk of education expenditure takes place within education districts but the controlling, forecasting and budgeting of expenditure takes place at the Provincial Head Office. Most high schools surveyed experience problems with the current funding policy of the Department of Education. The relative poverty of the community around the school impacts negatively on the parent’s ability to support the school. iv The budgeting process of the Department of Education should follow a bottom-up approach to budgeting. Therefore, the district office budget should be informed by the needs of the school and the provincial budget be informed by the district office budget. The management and administrative capacity at the district office need to be developed to ensure effective budgeting.
- Full Text:
- Date Issued: 2004
Evaluation and optimization of selected methods of arsenic removal from industrial effluent
- Authors: Rubidge, Gletwyn Robert
- Date: 2004
- Subjects: Arsenic wastes , Water -- Purification -- Arsenic removal , Sewage -- Purification
- Language: English
- Type: Thesis , Doctoral , DTech (Chemistry)
- Identifier: vital:10981 , http://hdl.handle.net/10948/230 , Arsenic wastes , Water -- Purification -- Arsenic removal , Sewage -- Purification
- Description: This research was directed at reducing arsenic levels in the effluents generated at the Canelands facility that manufactures monosodium methyl arsenate. Two effluent streams containing arsenic have to be considered, a raw water stream that is treated on site and a brine stream that is disposed of by sea outfall. Removal of arsenate from aqueous media by coagulation was investigated and models were developed describing selected variables that influence the removal of the arsenate. Three coagulant systems were investigated, namely aluminium(III) coagulation, iron(III) coagulation and binary mixtures of aluminium(III) and iron(III). Researchers have studied individual aluminium (III) sulphate and iron(III) chloride coagulation. No detailed research and modelling had, however, been carried out on the use of binary mixtures of aluminium (III) sulphate and iron (III) chloride coagulation of aqueous arsenate, nor had individual aluminium(III) sulphate and iron(III) chloride coagulation of arsenate been modelled at relatively high arsenate concentrations. The models that were generated were validated statistically and experimentally. The variables investigated in the aluminium(III) model included initial arsenate concentration, pH, polymeric flocculent concentration, aluminium(III) concentration and settling time. The variables modelled in the iron(III) coagulation were initial arsenate concentration, pH, polymeric flocculent concentration, and iron(III) to arsenic mole ratio. The modelling of the binary coagulant system included initial arsenate concentration, pH, iron (III) concentration, aluminium(III) concentration, and flocculent concentration as variables. The most efficient arsenic removal by coagulation was iron(III), followed by the binary mixture of aluminium(III) and iron(III) and the weakest coagulant was aluminium(III) sulphate. Scale-up coagulations performed on real raw water samples at a 50 litre volume showed that iron(III) was the most efficient coagulant (on a molar basis) followed closely by the binary mixture, while aluminium(III) coagulation was considerably weaker. The residual arsenic levels of the iron(III) and the binary coagulation systems met the effluent discharge criteria, but the aluminium coagulation system did not. Leaching tests showed that the iron(III) sludge was the most stable followed by the sludge of the binary mixture and the aluminium(III)-based sludge leached arsenic most readily. Settling rate studies showed that the flocs of the iron(III) coagulations settled the fastest, followed by binary mixture flocs and the aluminium flocs settled the slowest. The flocs of the binary mixture had the lowest volume, followed by the iron(III) flocs, while the aluminium(III) flocs were the most voluminous. Based on current operations of the raw water treatment plant the aluminium(III)-based coagulation is the most cost efficient. Given a relative costing of 1.00 for the aluminium(III) coagulation, the iron(III) chloride-based coagulation would be 2.67 times more expensive and the equimolar binary mixed aluminium(III)/iron(III) system would be 1.84 times the cost of aluminium(III) coagulation.
- Full Text:
- Date Issued: 2004
- Authors: Rubidge, Gletwyn Robert
- Date: 2004
- Subjects: Arsenic wastes , Water -- Purification -- Arsenic removal , Sewage -- Purification
- Language: English
- Type: Thesis , Doctoral , DTech (Chemistry)
- Identifier: vital:10981 , http://hdl.handle.net/10948/230 , Arsenic wastes , Water -- Purification -- Arsenic removal , Sewage -- Purification
- Description: This research was directed at reducing arsenic levels in the effluents generated at the Canelands facility that manufactures monosodium methyl arsenate. Two effluent streams containing arsenic have to be considered, a raw water stream that is treated on site and a brine stream that is disposed of by sea outfall. Removal of arsenate from aqueous media by coagulation was investigated and models were developed describing selected variables that influence the removal of the arsenate. Three coagulant systems were investigated, namely aluminium(III) coagulation, iron(III) coagulation and binary mixtures of aluminium(III) and iron(III). Researchers have studied individual aluminium (III) sulphate and iron(III) chloride coagulation. No detailed research and modelling had, however, been carried out on the use of binary mixtures of aluminium (III) sulphate and iron (III) chloride coagulation of aqueous arsenate, nor had individual aluminium(III) sulphate and iron(III) chloride coagulation of arsenate been modelled at relatively high arsenate concentrations. The models that were generated were validated statistically and experimentally. The variables investigated in the aluminium(III) model included initial arsenate concentration, pH, polymeric flocculent concentration, aluminium(III) concentration and settling time. The variables modelled in the iron(III) coagulation were initial arsenate concentration, pH, polymeric flocculent concentration, and iron(III) to arsenic mole ratio. The modelling of the binary coagulant system included initial arsenate concentration, pH, iron (III) concentration, aluminium(III) concentration, and flocculent concentration as variables. The most efficient arsenic removal by coagulation was iron(III), followed by the binary mixture of aluminium(III) and iron(III) and the weakest coagulant was aluminium(III) sulphate. Scale-up coagulations performed on real raw water samples at a 50 litre volume showed that iron(III) was the most efficient coagulant (on a molar basis) followed closely by the binary mixture, while aluminium(III) coagulation was considerably weaker. The residual arsenic levels of the iron(III) and the binary coagulation systems met the effluent discharge criteria, but the aluminium coagulation system did not. Leaching tests showed that the iron(III) sludge was the most stable followed by the sludge of the binary mixture and the aluminium(III)-based sludge leached arsenic most readily. Settling rate studies showed that the flocs of the iron(III) coagulations settled the fastest, followed by binary mixture flocs and the aluminium flocs settled the slowest. The flocs of the binary mixture had the lowest volume, followed by the iron(III) flocs, while the aluminium(III) flocs were the most voluminous. Based on current operations of the raw water treatment plant the aluminium(III)-based coagulation is the most cost efficient. Given a relative costing of 1.00 for the aluminium(III) coagulation, the iron(III) chloride-based coagulation would be 2.67 times more expensive and the equimolar binary mixed aluminium(III)/iron(III) system would be 1.84 times the cost of aluminium(III) coagulation.
- Full Text:
- Date Issued: 2004
Evidence for Archaean lamprophyre from the Kaapvaal Craton, South Africa
- Prevec, S A, Anhaeusser, C R, Poujol, M
- Authors: Prevec, S A , Anhaeusser, C R , Poujol, M
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6739 , http://hdl.handle.net/10962/d1007555
- Description: A suite of mafic dykes occurs as a late component in a wellcharacterized trondhjemite–tonalite–diorite–granodiorite assemblage in the Johannesburg Dome of the central Kaapvaal Craton, southern Africa. The dykes have been subdivided into two sets, based on their orientation, and major and trace element geochemistry. Set 1 dykes are characterized by elevated SiO2, Al2O3 and TiO2, and particularly by enriched LILE and HSFE (e.g. Zr > 200 ppm, Nb > 20 ppm, Ba > 300 ppm), higher than in any of the accompanying felsic rocks. REE and trace element values for Set 1 dykes are similar to those for calc-alkaline lamprophyres. The Set 2 dykes have similar trace element distributions, but are significantly less enriched in general, and are broadly tholeiitic in composition, with enriched MgO (>11 wt. percentage) indicative of an olivine–phyric tholeiitic basaltic protolith. Field relationships and available U–Pb zircon geochronology indicate that the dykes are contemporaneous with components of the trondhjemitic host rocks, and with late granodiorites. The geochemical, geochronological and field petrological setting indicates partial melting of basaltic and eclogitic lithosphere at c. 3120 Myr ago in the basal Kaapvaal Craton, and subsequent emplacement into pre-existing c. 3430 Myr tonalitic to dioritic crust.
- Full Text:
- Date Issued: 2004
- Authors: Prevec, S A , Anhaeusser, C R , Poujol, M
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6739 , http://hdl.handle.net/10962/d1007555
- Description: A suite of mafic dykes occurs as a late component in a wellcharacterized trondhjemite–tonalite–diorite–granodiorite assemblage in the Johannesburg Dome of the central Kaapvaal Craton, southern Africa. The dykes have been subdivided into two sets, based on their orientation, and major and trace element geochemistry. Set 1 dykes are characterized by elevated SiO2, Al2O3 and TiO2, and particularly by enriched LILE and HSFE (e.g. Zr > 200 ppm, Nb > 20 ppm, Ba > 300 ppm), higher than in any of the accompanying felsic rocks. REE and trace element values for Set 1 dykes are similar to those for calc-alkaline lamprophyres. The Set 2 dykes have similar trace element distributions, but are significantly less enriched in general, and are broadly tholeiitic in composition, with enriched MgO (>11 wt. percentage) indicative of an olivine–phyric tholeiitic basaltic protolith. Field relationships and available U–Pb zircon geochronology indicate that the dykes are contemporaneous with components of the trondhjemitic host rocks, and with late granodiorites. The geochemical, geochronological and field petrological setting indicates partial melting of basaltic and eclogitic lithosphere at c. 3120 Myr ago in the basal Kaapvaal Craton, and subsequent emplacement into pre-existing c. 3430 Myr tonalitic to dioritic crust.
- Full Text:
- Date Issued: 2004
Evolution of Labeo victorianus predates the Pleistocene desiccation of Lake Victoria: evidence from mitochondrial DNA sequence variation
- Rutaisire, Justus, Booth, Anthony J, Masembe, C, Nyakaana, S, Muwanika, V B
- Authors: Rutaisire, Justus , Booth, Anthony J , Masembe, C , Nyakaana, S , Muwanika, V B
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6762 , http://hdl.handle.net/10962/d1007924
- Description: Geological data show that Lake Victoria dried out some 15 000 years ago. These data suggest that the entire faunal diversity within the lake has evolved since this time. However, mitochondrial DNA sequence diversity in the endemic cyprinid fish, Labeo victorianus, was high (24 haplotypes in 38 individuals; percentage sequence divergence of 0.74%), suggesting that the evolution of this species predates this Late Pleistocene climatological event. This finding is consistent with what has been reported earlier for cichlid fishes in the lake.
- Full Text:
- Date Issued: 2004
- Authors: Rutaisire, Justus , Booth, Anthony J , Masembe, C , Nyakaana, S , Muwanika, V B
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6762 , http://hdl.handle.net/10962/d1007924
- Description: Geological data show that Lake Victoria dried out some 15 000 years ago. These data suggest that the entire faunal diversity within the lake has evolved since this time. However, mitochondrial DNA sequence diversity in the endemic cyprinid fish, Labeo victorianus, was high (24 haplotypes in 38 individuals; percentage sequence divergence of 0.74%), suggesting that the evolution of this species predates this Late Pleistocene climatological event. This finding is consistent with what has been reported earlier for cichlid fishes in the lake.
- Full Text:
- Date Issued: 2004
Examining the feasibility of introducing environmental surcharges to finance local coastal management initiatives in South Africa : a case study in Plettenberg Bay
- Authors: Mollatt, David G R
- Date: 2004
- Subjects: Marine resources -- South Africa Marine resources conservation -- South Africa Coastal zone management -- South Africa Marine parks and reserves -- Management--South Africa Tourism--South Africa -- Taxation Tourism -- South Africa -- Economic aspects
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:999 , http://hdl.handle.net/10962/d1002734
- Description: The management of coastal resources in South Africa has come under review as a result of the degradation of environmental resources along the coast. The challenge being faced by resource managers is to achieve economic growth while sustaining South Africa’s coastal resource base (Nobel, 2000). The South African government (RSA, 2000) has developed a coastal management strategy to meet this challenge: The strategy involves the inclusion of all stakeholders in the formation of policy regarding the management of coastal resources, in a more integrated approach to coastal management. To effectively achieve this stakeholder inclusion, it has become necessary to decentralize the political, administrative and fiscal authority to conduct coastal management functions. With regard to the need for fiscal decentralisation this thesis considers the possibility of implementing localised environmental surcharges to finance coastal management initiatives. The ability of the White Paper for Sustainable Coastal Development (RSA, 2000) to provide theformal institutional structure necessary for the introduction of environmental surcharges is firstconsidered. It is shown that the decentralised management strategy has the potential to create a management style that is transparent and accountability orientated. In addition to this the style is capable of adapting to dynamic local coastal conditions and is therefore an appropriate direction in which to steer coastal management in South Africa. The effectiveness of coastal co-management as an informal institutional arrangement is then examined. Provided that local Coastal Management Fora are created to include all relevant stakeholders and that a source of long term financing is secured co-management has the potential to create the conditions necessary for effective coastal management. With regard to a source of long term financing, local environmental surcharges to finance coastal management initiatives are considered. The public’s willingness to contribute to such a surcharge is analysed in the context of Plettenberg Bay by probing their willingness to pay (WTP) for a Bay Management Plan. A survey instrument is developed to measure the public’s WTP. The design of the instrument is based on the Contingent Valuation (CV) method that is used to analyse the nonmarket benefits that environmental resources (such as Plettenberg Bay) provide the public. It is found that the resident population is willing to pay R15 per month toward a Bay Management Plan whilst domestic and foreign tourists respectively are willing to pay R6 and R22 daily. The aggregation of these WTP estimates yields a total passive use value of between R15 397 900 – R20330 500 annually. This nuclear value of the Bay should be included in the formation of local coastal management policy and provides guidance for the introduction of a local environmental surcharge. A budget for a Bay Management Plan is proposed and a progressive surcharge based on municipal property value is set. To finance the local residents’ share of the budget, a monthly surcharge of R1 would be required of the average valued property. To calculate the domestic and foreign tourist contribution to the budget a schedule of accommodation offering property will be required. However, to finance the entire budget a residential surcharge of approximately R10 would be required of the average valued property. This figure is well below the average resident population WTP of R15, highlighting the fact that an environmental surcharge in Plettenberg Bay is indeed feasible. The difference in reported WTP and the contribution required to finance the Bay Management Plan also highlights that there is scope for experimentation in the introduction of such a surcharge.
- Full Text:
- Date Issued: 2004
- Authors: Mollatt, David G R
- Date: 2004
- Subjects: Marine resources -- South Africa Marine resources conservation -- South Africa Coastal zone management -- South Africa Marine parks and reserves -- Management--South Africa Tourism--South Africa -- Taxation Tourism -- South Africa -- Economic aspects
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:999 , http://hdl.handle.net/10962/d1002734
- Description: The management of coastal resources in South Africa has come under review as a result of the degradation of environmental resources along the coast. The challenge being faced by resource managers is to achieve economic growth while sustaining South Africa’s coastal resource base (Nobel, 2000). The South African government (RSA, 2000) has developed a coastal management strategy to meet this challenge: The strategy involves the inclusion of all stakeholders in the formation of policy regarding the management of coastal resources, in a more integrated approach to coastal management. To effectively achieve this stakeholder inclusion, it has become necessary to decentralize the political, administrative and fiscal authority to conduct coastal management functions. With regard to the need for fiscal decentralisation this thesis considers the possibility of implementing localised environmental surcharges to finance coastal management initiatives. The ability of the White Paper for Sustainable Coastal Development (RSA, 2000) to provide theformal institutional structure necessary for the introduction of environmental surcharges is firstconsidered. It is shown that the decentralised management strategy has the potential to create a management style that is transparent and accountability orientated. In addition to this the style is capable of adapting to dynamic local coastal conditions and is therefore an appropriate direction in which to steer coastal management in South Africa. The effectiveness of coastal co-management as an informal institutional arrangement is then examined. Provided that local Coastal Management Fora are created to include all relevant stakeholders and that a source of long term financing is secured co-management has the potential to create the conditions necessary for effective coastal management. With regard to a source of long term financing, local environmental surcharges to finance coastal management initiatives are considered. The public’s willingness to contribute to such a surcharge is analysed in the context of Plettenberg Bay by probing their willingness to pay (WTP) for a Bay Management Plan. A survey instrument is developed to measure the public’s WTP. The design of the instrument is based on the Contingent Valuation (CV) method that is used to analyse the nonmarket benefits that environmental resources (such as Plettenberg Bay) provide the public. It is found that the resident population is willing to pay R15 per month toward a Bay Management Plan whilst domestic and foreign tourists respectively are willing to pay R6 and R22 daily. The aggregation of these WTP estimates yields a total passive use value of between R15 397 900 – R20330 500 annually. This nuclear value of the Bay should be included in the formation of local coastal management policy and provides guidance for the introduction of a local environmental surcharge. A budget for a Bay Management Plan is proposed and a progressive surcharge based on municipal property value is set. To finance the local residents’ share of the budget, a monthly surcharge of R1 would be required of the average valued property. To calculate the domestic and foreign tourist contribution to the budget a schedule of accommodation offering property will be required. However, to finance the entire budget a residential surcharge of approximately R10 would be required of the average valued property. This figure is well below the average resident population WTP of R15, highlighting the fact that an environmental surcharge in Plettenberg Bay is indeed feasible. The difference in reported WTP and the contribution required to finance the Bay Management Plan also highlights that there is scope for experimentation in the introduction of such a surcharge.
- Full Text:
- Date Issued: 2004
Exploring health literacy assessment : the relexicalisation of a health literacy test from the U.S. for application in a South African population
- La Rose, Christopher Michael
- Authors: La Rose, Christopher Michael
- Date: 2004
- Subjects: Rapid Estimate of Adult Literacy in Medicine , Educational tests and measurements , Literacy -- South Africa--Evaluation , Health education -- South Africa -- Evaluation
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2373 , http://hdl.handle.net/10962/d1005708 , Rapid Estimate of Adult Literacy in Medicine , Educational tests and measurements , Literacy -- South Africa--Evaluation , Health education -- South Africa -- Evaluation
- Description: The Rapid Estimate of Adult Literacy in Medicine (REALM) is a standardised health literacy test developed in the United States that has been previously administered and researched in South Africa (Lecoko, 2000). It is an objective vocabulary test which uses item recognition of 66 health-related words where recognition is measured by pronunciation. It is designed as a screening instrument to identifY the health literacy levels of patients in clinics. Lecoko (2000) found the REALM to be largely inapplicable in a South African setting, in that only eight out of the 66 words could be deemed acceptable, in that they could be either both adequately pronounced and adequately comprehended or both inadequately pronounced and inadequately comprehended. This may have occurred for a number of reasons, including the administration of the test in a population for whom English is a second or other language, and inaccurate measurement of pronunciation and comprehension of words, with a key problem being that the choice of words in the original REALM may not accurately represent the range of conditions and issues in a South African healthcare setting. This thesis was therefore premised on the principled relexicalisation of the REALM, that replacement of the words used in the test, using a sample gathered from health information and promotion texts in local clinics, would improve its applicability. In this regard, an exhaustive sample was gathered and analysed and 66 new words were chosen. The test was also modified to include a more principled approach to pronunciation and comprehension issues, and to account for language proficiency differences in administering an English language test in an English second language population. This modified test, referred to as the REALM-M was administered to a group of respondents who were statistically similar to the group to whom the REALM had originally been administered, and the results were compared. It was found that relexicalisation increased the number of acceptable words on the test from eight to 38. However, researching the key discourses surrounding health literacy and comparing these with current discourses about literacy beyond the field of health care revealed that despite improved content validity over the REALM, the REALM-M lacked construct validity. This provided the opportunity to discuss the discourses of health literacy and to suggest the application of alternative paradigms in this field.
- Full Text:
- Date Issued: 2004
- Authors: La Rose, Christopher Michael
- Date: 2004
- Subjects: Rapid Estimate of Adult Literacy in Medicine , Educational tests and measurements , Literacy -- South Africa--Evaluation , Health education -- South Africa -- Evaluation
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2373 , http://hdl.handle.net/10962/d1005708 , Rapid Estimate of Adult Literacy in Medicine , Educational tests and measurements , Literacy -- South Africa--Evaluation , Health education -- South Africa -- Evaluation
- Description: The Rapid Estimate of Adult Literacy in Medicine (REALM) is a standardised health literacy test developed in the United States that has been previously administered and researched in South Africa (Lecoko, 2000). It is an objective vocabulary test which uses item recognition of 66 health-related words where recognition is measured by pronunciation. It is designed as a screening instrument to identifY the health literacy levels of patients in clinics. Lecoko (2000) found the REALM to be largely inapplicable in a South African setting, in that only eight out of the 66 words could be deemed acceptable, in that they could be either both adequately pronounced and adequately comprehended or both inadequately pronounced and inadequately comprehended. This may have occurred for a number of reasons, including the administration of the test in a population for whom English is a second or other language, and inaccurate measurement of pronunciation and comprehension of words, with a key problem being that the choice of words in the original REALM may not accurately represent the range of conditions and issues in a South African healthcare setting. This thesis was therefore premised on the principled relexicalisation of the REALM, that replacement of the words used in the test, using a sample gathered from health information and promotion texts in local clinics, would improve its applicability. In this regard, an exhaustive sample was gathered and analysed and 66 new words were chosen. The test was also modified to include a more principled approach to pronunciation and comprehension issues, and to account for language proficiency differences in administering an English language test in an English second language population. This modified test, referred to as the REALM-M was administered to a group of respondents who were statistically similar to the group to whom the REALM had originally been administered, and the results were compared. It was found that relexicalisation increased the number of acceptable words on the test from eight to 38. However, researching the key discourses surrounding health literacy and comparing these with current discourses about literacy beyond the field of health care revealed that despite improved content validity over the REALM, the REALM-M lacked construct validity. This provided the opportunity to discuss the discourses of health literacy and to suggest the application of alternative paradigms in this field.
- Full Text:
- Date Issued: 2004