The deaths of Cordelia and Lear
- Authors: Butler, Guy F
- Date: 1993
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457881 , vital:75687 , https://hdl.handle.net/10520/AJA1011582X_33
- Description:
- Full Text:
- Authors: Butler, Guy F
- Date: 1993
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457881 , vital:75687 , https://hdl.handle.net/10520/AJA1011582X_33
- Description:
- Full Text:
The domestic worker some considerations for law reform
- Meintjes-van der Walt, Lirieka
- Authors: Meintjes-van der Walt, Lirieka
- Date: 1993
- Subjects: Household employees -- Law and legislation -- South Africa , Black people -- Employment -- South Africa , Women -- Employment -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3683 , http://hdl.handle.net/10962/d1003198 , Household employees -- Law and legislation -- South Africa , Black people -- Employment -- South Africa , Women -- Employment -- South Africa
- Description: This thesis examines ways in which domestic workers in South Africa could be included within the scope of existing industrial legislation. At present the legal position of a work force of 862 000 is regulated by the common law contract of service. Socio-economic factors form the background of this investigation,which first sets out to determine whether the common-law contract of employment is capable of equitably regulating the employment relationship. The fallacy of the assumption that individuals agree on the terms of exchange in the employment contract on the basis of juridical equality, and the tenuous nature of the common-law employment relationship in the case of domestic workers are revealed. In the absence of any current statutory minima the employment contract is used to deprive domestic workers of what little protection they enjoy at common law. The two ways in which the individual employee's conditions of service can be protected from terms favouring the stronger of the two contracting parties are discussed. These are collective bargaining and statutory regulation. Difficulties experienced by domestic workers in respect of collective bargaining, whether they be included under the Labour Relations Act or not, are indicated. Proposals for including domestic workers under the Basic Conditions of Employment Act are evaluated in the light of legislation in the United States of America, Zimbabwe, Swaziland and Namibia. Ways of minimum-wage fixing are investigated, and it is concluded that the provisions of the Wage Act could be adapted for domestic workers. The 'unfair labour practice'concept is examined and the implications of its application for the domestic labour sector evaluated. It is recommended that the concept 'fairness' in the Labour Relations Act should apply to domestic workers, but that a code of practice be drafted to provide conceptions of 'fairness' as guidelines for employment behaviour. It is suggested that the parties refer disputes to mediation before being granted access to a Small Labour Court established for this purpose. In conclusion a draft code of practice is presented, as a basis for negotiation at a forum representative of the major actors in the domestic labour arena.
- Full Text:
- Authors: Meintjes-van der Walt, Lirieka
- Date: 1993
- Subjects: Household employees -- Law and legislation -- South Africa , Black people -- Employment -- South Africa , Women -- Employment -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3683 , http://hdl.handle.net/10962/d1003198 , Household employees -- Law and legislation -- South Africa , Black people -- Employment -- South Africa , Women -- Employment -- South Africa
- Description: This thesis examines ways in which domestic workers in South Africa could be included within the scope of existing industrial legislation. At present the legal position of a work force of 862 000 is regulated by the common law contract of service. Socio-economic factors form the background of this investigation,which first sets out to determine whether the common-law contract of employment is capable of equitably regulating the employment relationship. The fallacy of the assumption that individuals agree on the terms of exchange in the employment contract on the basis of juridical equality, and the tenuous nature of the common-law employment relationship in the case of domestic workers are revealed. In the absence of any current statutory minima the employment contract is used to deprive domestic workers of what little protection they enjoy at common law. The two ways in which the individual employee's conditions of service can be protected from terms favouring the stronger of the two contracting parties are discussed. These are collective bargaining and statutory regulation. Difficulties experienced by domestic workers in respect of collective bargaining, whether they be included under the Labour Relations Act or not, are indicated. Proposals for including domestic workers under the Basic Conditions of Employment Act are evaluated in the light of legislation in the United States of America, Zimbabwe, Swaziland and Namibia. Ways of minimum-wage fixing are investigated, and it is concluded that the provisions of the Wage Act could be adapted for domestic workers. The 'unfair labour practice'concept is examined and the implications of its application for the domestic labour sector evaluated. It is recommended that the concept 'fairness' in the Labour Relations Act should apply to domestic workers, but that a code of practice be drafted to provide conceptions of 'fairness' as guidelines for employment behaviour. It is suggested that the parties refer disputes to mediation before being granted access to a Small Labour Court established for this purpose. In conclusion a draft code of practice is presented, as a basis for negotiation at a forum representative of the major actors in the domestic labour arena.
- Full Text:
The ecology of the South African citrus thrips, Scirtothrips aurantii Faure and its economic implications
- Authors: Gilbert, Martin Jeffray
- Date: 1993
- Subjects: Thrips -- Control -- South Africa Citrus -- Diseases and pests -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5673 , http://hdl.handle.net/10962/d1005358
- Description: The South African Citrus Thrips, Scirtothrips aurantii Faure (Thysanoptera: Thripidae) has been a serious pest of the citrus industry of Southern Africa for over 70 years. It is indigenous to Africa and has no recorded parasitoids and, in most citrus-growing regions, predators are not economically effective. Firstly, in this study, the general ecology of thrips was reviewed along with the recorded history of S. aurantii and its control. Host plant relationships of S. aurantii were then examined and wild hosts were not found to be important in promoting citrus thrips outbreaks in the orchard after flowering. In addition, Scirtothrips dorsalis Hood, which attacks citrus in Asia, was collected for the first time in Africa, but from Castor Oil plant. It is therefore a potential pest of citrus here. Notes on its appearance compared to that of S. aurantii were prepared. Weekly sampling of S. aurantii adults was carried out from June 1984 to May 1990. Population fluctuations were then correlated with phenology of the citrus trees and the direct and indirect effects of weather. Temperature and rainfall were not found to be significantly directly correlated with thrips numbers recorded. However, the indirect effects of rainfall were important in promoting a large winter thrips population in certain years. Relatively high rainfall during March and April compared to that of the previous January and February stimulated atypical flushing of the citrus trees during autumn and the setting of out-of-season fruit. S. aurantii then exploited this unusual food source and high numbers were subsequently recorded in the following winter; as well as in spring. Thus the mild winter climate alone could not suppress thrips numbers at Letaba. Dispersal/Emergence traps, which are used in the U.S.A. for the monitoring of Scirtothrips citri, were evaluated over 24 months, and were effective in recording population peaks of S. aurantii. The emergence rate of adults in relation to second instar larvae trapped was 43.7%. 35.7% of adults caught after emerging from the soil were males and 64.3 were females. In contrast, yellow traps had recorded 59.1% males and 40.9% females over the same period. The yellow traps were subsequently found to be biased towards male catches when young fruit and/or soft flush was present on the citrus trees. Relative inhibition of female flight activity during times of food abundance is known in other thrips species. During times of food scarcity, the bias in the yellow trap results disappeared. At Letaba Estates, availability of food rather than the direct effects of weather was seen to be the most important factor in governing S. aurantii numbers. Because of the importance of soft flush in the promotion of S. aurantii population increase, it is recommended that more attention should be given to the control of thrips on, as well as conducting surveys for, this food source. As the climate at Letaba is so favourable for citrus thrips, even during winter, it is further recommended that trapping for S. aurantii is carried out throughout the year. Furthermore, males and females should be recorded separately in trapping results as the sex ratio gives an indication of the phenological state of the tree.
- Full Text:
- Authors: Gilbert, Martin Jeffray
- Date: 1993
- Subjects: Thrips -- Control -- South Africa Citrus -- Diseases and pests -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5673 , http://hdl.handle.net/10962/d1005358
- Description: The South African Citrus Thrips, Scirtothrips aurantii Faure (Thysanoptera: Thripidae) has been a serious pest of the citrus industry of Southern Africa for over 70 years. It is indigenous to Africa and has no recorded parasitoids and, in most citrus-growing regions, predators are not economically effective. Firstly, in this study, the general ecology of thrips was reviewed along with the recorded history of S. aurantii and its control. Host plant relationships of S. aurantii were then examined and wild hosts were not found to be important in promoting citrus thrips outbreaks in the orchard after flowering. In addition, Scirtothrips dorsalis Hood, which attacks citrus in Asia, was collected for the first time in Africa, but from Castor Oil plant. It is therefore a potential pest of citrus here. Notes on its appearance compared to that of S. aurantii were prepared. Weekly sampling of S. aurantii adults was carried out from June 1984 to May 1990. Population fluctuations were then correlated with phenology of the citrus trees and the direct and indirect effects of weather. Temperature and rainfall were not found to be significantly directly correlated with thrips numbers recorded. However, the indirect effects of rainfall were important in promoting a large winter thrips population in certain years. Relatively high rainfall during March and April compared to that of the previous January and February stimulated atypical flushing of the citrus trees during autumn and the setting of out-of-season fruit. S. aurantii then exploited this unusual food source and high numbers were subsequently recorded in the following winter; as well as in spring. Thus the mild winter climate alone could not suppress thrips numbers at Letaba. Dispersal/Emergence traps, which are used in the U.S.A. for the monitoring of Scirtothrips citri, were evaluated over 24 months, and were effective in recording population peaks of S. aurantii. The emergence rate of adults in relation to second instar larvae trapped was 43.7%. 35.7% of adults caught after emerging from the soil were males and 64.3 were females. In contrast, yellow traps had recorded 59.1% males and 40.9% females over the same period. The yellow traps were subsequently found to be biased towards male catches when young fruit and/or soft flush was present on the citrus trees. Relative inhibition of female flight activity during times of food abundance is known in other thrips species. During times of food scarcity, the bias in the yellow trap results disappeared. At Letaba Estates, availability of food rather than the direct effects of weather was seen to be the most important factor in governing S. aurantii numbers. Because of the importance of soft flush in the promotion of S. aurantii population increase, it is recommended that more attention should be given to the control of thrips on, as well as conducting surveys for, this food source. As the climate at Letaba is so favourable for citrus thrips, even during winter, it is further recommended that trapping for S. aurantii is carried out throughout the year. Furthermore, males and females should be recorded separately in trapping results as the sex ratio gives an indication of the phenological state of the tree.
- Full Text:
The effect of hydrostatic carbon dioxide pressure and extracellular ethanol on the performance of the yeast strain Saccharomyces cerevisiae during fermentation
- Authors: Longden, Nicholas Guy
- Date: 1993
- Subjects: Brewing -- Microbiology , Yeast , Fermentation , Saccharomyces cerevisiae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4044 , http://hdl.handle.net/10962/d1004105 , Brewing -- Microbiology , Yeast , Fermentation , Saccharomyces cerevisiae
- Description: The brewing industry constantly experiences problems in trying to maintain the quality of beer produced. Unfavourable conditions during fermentation may alter the performance of the yeast strain Saccharomyces cerevisiae, resulting in a "poor" end-product. It has been established that high concentrations of extracellular ethanol, when added to the fermentation medium inhibit yeast activity. It has been recently suggested that increased carbon dioxide pressure could inactivate the yeast activity adding to further brewing problems. The aim of this study was to investigate the effect of extracellular carbon dioxide pressure and ethanol addition, on yeast performance when added to a fermentation medium, and to establish whether an inhibitory relationship existed between ethanol and carbon dioxide pressure, when combined and added to the fermentation medium. Dissolved C0₂ in the medium, medium pH and substrate utilisation were analysed daily during a fermentation, as were membrane fatty acid composition. These parameters were used to assess the effect of ethanol and carbon dioxide on the yeast performance and consequently the final end-product. Supplementing the medium with extracellular ethanol, even as low as 5%, was shown to inhibit yeast performance during fermentation. This effect was even more marked as the ethanol concentration was increased, with almost total inhibition of yeast activity occuring after the addition of 15% ethanol (v/v). A similar effect was observed when elevated C0₂ pressures were applied to the medium, and although low C0₂ pressures initially induced the synthesis of saturated yeast membrane fatty acids, elevated C0₂ pressures (greater than 1,0 atm.) was shown to follow a similar inhibitory trend, if not as dramatic, as ethanol. A combination of both ethanol and C0₂ pressure showed a further increase in the level of yeast inhibition, although the low C0₂ pressure appeared to initially inhibit the toxicity of ethanol on the yeast. Increasing the levels of the C0₂/ethanol treatment (1,0 atm.), showed a synergistic effect on yeast performance. The results of this study indicate that both extracellular ethanol and carbon dioxide do appear to inhibit yeast performance and affect membrane fatty acid composition of the cells by inhibiting the synthesis of the respective fatty acid. This affect has a significant bearing on the general metabolism of the yeast cell.
- Full Text:
- Authors: Longden, Nicholas Guy
- Date: 1993
- Subjects: Brewing -- Microbiology , Yeast , Fermentation , Saccharomyces cerevisiae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4044 , http://hdl.handle.net/10962/d1004105 , Brewing -- Microbiology , Yeast , Fermentation , Saccharomyces cerevisiae
- Description: The brewing industry constantly experiences problems in trying to maintain the quality of beer produced. Unfavourable conditions during fermentation may alter the performance of the yeast strain Saccharomyces cerevisiae, resulting in a "poor" end-product. It has been established that high concentrations of extracellular ethanol, when added to the fermentation medium inhibit yeast activity. It has been recently suggested that increased carbon dioxide pressure could inactivate the yeast activity adding to further brewing problems. The aim of this study was to investigate the effect of extracellular carbon dioxide pressure and ethanol addition, on yeast performance when added to a fermentation medium, and to establish whether an inhibitory relationship existed between ethanol and carbon dioxide pressure, when combined and added to the fermentation medium. Dissolved C0₂ in the medium, medium pH and substrate utilisation were analysed daily during a fermentation, as were membrane fatty acid composition. These parameters were used to assess the effect of ethanol and carbon dioxide on the yeast performance and consequently the final end-product. Supplementing the medium with extracellular ethanol, even as low as 5%, was shown to inhibit yeast performance during fermentation. This effect was even more marked as the ethanol concentration was increased, with almost total inhibition of yeast activity occuring after the addition of 15% ethanol (v/v). A similar effect was observed when elevated C0₂ pressures were applied to the medium, and although low C0₂ pressures initially induced the synthesis of saturated yeast membrane fatty acids, elevated C0₂ pressures (greater than 1,0 atm.) was shown to follow a similar inhibitory trend, if not as dramatic, as ethanol. A combination of both ethanol and C0₂ pressure showed a further increase in the level of yeast inhibition, although the low C0₂ pressure appeared to initially inhibit the toxicity of ethanol on the yeast. Increasing the levels of the C0₂/ethanol treatment (1,0 atm.), showed a synergistic effect on yeast performance. The results of this study indicate that both extracellular ethanol and carbon dioxide do appear to inhibit yeast performance and affect membrane fatty acid composition of the cells by inhibiting the synthesis of the respective fatty acid. This affect has a significant bearing on the general metabolism of the yeast cell.
- Full Text:
The effect of short chain fatty acids on picornavirus replication
- Authors: Ismail-Cassim, Nazeem
- Date: 1993
- Subjects: Viruses -- Reproduction , Picornaviruses , Antiviral agents -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4030 , http://hdl.handle.net/10962/d1004090 , Viruses -- Reproduction , Picornaviruses , Antiviral agents -- Research
- Description: Picornavirus proteins VP1 to VP3 are exposed on the surface of the virus particle whereas VP4 is internal and modified at its amino terminus by the addition of myristic acid (Chow et al., 1987; Paul et al., 1987). Myristic acid occupies a position in the core of mature poliovirus particles; it has been suggested that it may be important for particle integrity or in the localization of the capsid protein precursor on the hydrophobic membranes during virion assembly (Chow et al., 1987). To determine the function of the amino-terminal myristylation of VP4 in picornaviruses, and to establish whether competition for the acylation site is a possible approach to antiviral chemotherapy, the effect of fatty acids on virus replication has been examined. Some fatty acids are able to enter picornavirus-infected cells and compete for the myristylation site on VP4. Unexpectedly, it was found that short chain fatty acids also inhibit an early event in the replication of bovine enterovirus (BEV) at concentrations which have no detectable effect on cellular macromolecular synthesis and cloning. These findings indicate that fatty acids inhibit cell-mediated uncoating. Short chain fatty acids inhibit the replication of bovine enterovirus but are almost ineffective against poliovirus type 1, coxsackievirus B5, encephalomyocarditis virus and human rhinovirus lB. Lauric acid binds to bovine enterovirus, thereby stabilizing the virus particle to heat degradation. Fatty acid-bound virions attach to susceptible cells but fail to undergo cell-mediated uncoating. The inhibitory effect is reversible with chloroform and may result from a hydrophobic interaction between the fatty acid and a specific site on the virus particie.
- Full Text:
- Authors: Ismail-Cassim, Nazeem
- Date: 1993
- Subjects: Viruses -- Reproduction , Picornaviruses , Antiviral agents -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4030 , http://hdl.handle.net/10962/d1004090 , Viruses -- Reproduction , Picornaviruses , Antiviral agents -- Research
- Description: Picornavirus proteins VP1 to VP3 are exposed on the surface of the virus particle whereas VP4 is internal and modified at its amino terminus by the addition of myristic acid (Chow et al., 1987; Paul et al., 1987). Myristic acid occupies a position in the core of mature poliovirus particles; it has been suggested that it may be important for particle integrity or in the localization of the capsid protein precursor on the hydrophobic membranes during virion assembly (Chow et al., 1987). To determine the function of the amino-terminal myristylation of VP4 in picornaviruses, and to establish whether competition for the acylation site is a possible approach to antiviral chemotherapy, the effect of fatty acids on virus replication has been examined. Some fatty acids are able to enter picornavirus-infected cells and compete for the myristylation site on VP4. Unexpectedly, it was found that short chain fatty acids also inhibit an early event in the replication of bovine enterovirus (BEV) at concentrations which have no detectable effect on cellular macromolecular synthesis and cloning. These findings indicate that fatty acids inhibit cell-mediated uncoating. Short chain fatty acids inhibit the replication of bovine enterovirus but are almost ineffective against poliovirus type 1, coxsackievirus B5, encephalomyocarditis virus and human rhinovirus lB. Lauric acid binds to bovine enterovirus, thereby stabilizing the virus particle to heat degradation. Fatty acid-bound virions attach to susceptible cells but fail to undergo cell-mediated uncoating. The inhibitory effect is reversible with chloroform and may result from a hydrophobic interaction between the fatty acid and a specific site on the virus particie.
- Full Text:
The fishes of Tristan Da Cunha and Gough Island (South Atlantic), and the effects of environmental seasonality on the biology of selected species
- Authors: Andrew, Timothy Gilbert
- Date: 1993
- Subjects: Fishes -- Tristan da Cunha Fishes -- Gough Island Fishes -- Conservation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5284 , http://hdl.handle.net/10962/d1005128
- Description: This study focuses on the taxonomy, biogeography and biological aspects of the fishes of Tristan da Cunha and Gough Island in the cental South Atlantic Ocean. Oceanographic measurements were undertaken to determine the position and nature of the Subtropical Convergence (STC) in the vicinity of the islands. The Tristan da Cunha group is thought to be situated on the northern edge of the STC while Gough Island is situated on the southern edge of the front. The seasonal environmental cycle at the islands is characterised by an annual sea surface temperature fluctuation of approximately 5 °C and an annual change in stratification of the water column. It is suggested that this increase in stratification at the STC, brought about in the summer by insolation warming the surface layers of the ocean, enhances primary production. The STC is identified as a unique habitat for fishes and as an important barrier to dispersal of species in the Southern Ocean. The present study has produced 18 new distributional records from the shelf waters of Tristan da Cunha and Gough Island. The fish fauna known from the shelf waters of these islands is reviewed, and a diagnosis, synonymy, and in some cases an illustration are provided. For certain species, brief notes on their biology, relative abundance and seasonal distribution are included. An analysis of the ichthyofaunal relationships between shallow water areas in the vicinity of the STC has resulted in the identification of a characteristic neritic STC ichthyofauna. The circumglobal distribution of many of these species is thought to be a consequence of a dispersive pelagic phase in their life-cycles. Biological processes in fishes at these islands are temporally and spatially affected by seasonal changes in oceanographic conditions. Seasonal sea temperature variation was identified as being an indicator of other oceanographic phenomena that may affect processes such as growth, reproduction and feeding in fishes at the islands. Most species have a summer spawning season and growth rate increased during the summer months. It was hypothesised that enhanced primary production and a related increase in food quality and availability during the summer were the major factors temporally regulating the growth and reproduction of fishes at the islands. Twenty families of neritic fishes have been recorded in the shelf waters of Tristan da Cunhaand Gough Island. Most families are represented by only one species. Because of this a wide range of life-history strategies are apparent in the fauna. Nevertheless, there are a number of common life-history characteristics shared by most of the neritic species. Firstly, the early lifehistory of many species included an extended pelagic phase which might have facilitated colonisation throughout the STC zone in the past, thereby regulating extant species diversity in this region. Secondly, the common occurrence of an extended summer breeding season and iteroparity suggested that these characters also contributed to survival in what is considered to be an unpredictable environment. It would appear that these common characteristics hold the key to the success of many fishes in the STC zone. This study has contributed to our understanding of oceanic island ecosystems and has revealed distributional patterns of fishes that were unknown previously. By focusing on the biological processes of selected species the regulatory role played by local environmental conditions became apparent. The results of this study are also relevant to proposed conservation measures for Tristan da Cunha and Gough Island.
- Full Text:
- Authors: Andrew, Timothy Gilbert
- Date: 1993
- Subjects: Fishes -- Tristan da Cunha Fishes -- Gough Island Fishes -- Conservation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5284 , http://hdl.handle.net/10962/d1005128
- Description: This study focuses on the taxonomy, biogeography and biological aspects of the fishes of Tristan da Cunha and Gough Island in the cental South Atlantic Ocean. Oceanographic measurements were undertaken to determine the position and nature of the Subtropical Convergence (STC) in the vicinity of the islands. The Tristan da Cunha group is thought to be situated on the northern edge of the STC while Gough Island is situated on the southern edge of the front. The seasonal environmental cycle at the islands is characterised by an annual sea surface temperature fluctuation of approximately 5 °C and an annual change in stratification of the water column. It is suggested that this increase in stratification at the STC, brought about in the summer by insolation warming the surface layers of the ocean, enhances primary production. The STC is identified as a unique habitat for fishes and as an important barrier to dispersal of species in the Southern Ocean. The present study has produced 18 new distributional records from the shelf waters of Tristan da Cunha and Gough Island. The fish fauna known from the shelf waters of these islands is reviewed, and a diagnosis, synonymy, and in some cases an illustration are provided. For certain species, brief notes on their biology, relative abundance and seasonal distribution are included. An analysis of the ichthyofaunal relationships between shallow water areas in the vicinity of the STC has resulted in the identification of a characteristic neritic STC ichthyofauna. The circumglobal distribution of many of these species is thought to be a consequence of a dispersive pelagic phase in their life-cycles. Biological processes in fishes at these islands are temporally and spatially affected by seasonal changes in oceanographic conditions. Seasonal sea temperature variation was identified as being an indicator of other oceanographic phenomena that may affect processes such as growth, reproduction and feeding in fishes at the islands. Most species have a summer spawning season and growth rate increased during the summer months. It was hypothesised that enhanced primary production and a related increase in food quality and availability during the summer were the major factors temporally regulating the growth and reproduction of fishes at the islands. Twenty families of neritic fishes have been recorded in the shelf waters of Tristan da Cunhaand Gough Island. Most families are represented by only one species. Because of this a wide range of life-history strategies are apparent in the fauna. Nevertheless, there are a number of common life-history characteristics shared by most of the neritic species. Firstly, the early lifehistory of many species included an extended pelagic phase which might have facilitated colonisation throughout the STC zone in the past, thereby regulating extant species diversity in this region. Secondly, the common occurrence of an extended summer breeding season and iteroparity suggested that these characters also contributed to survival in what is considered to be an unpredictable environment. It would appear that these common characteristics hold the key to the success of many fishes in the STC zone. This study has contributed to our understanding of oceanic island ecosystems and has revealed distributional patterns of fishes that were unknown previously. By focusing on the biological processes of selected species the regulatory role played by local environmental conditions became apparent. The results of this study are also relevant to proposed conservation measures for Tristan da Cunha and Gough Island.
- Full Text:
The formulation of modern power configurations in the Keiskammahoek district of the Ciskei from c.1948 to the present
- Westaway, Ashley Frank Hurford
- Authors: Westaway, Ashley Frank Hurford
- Date: 1993
- Subjects: Keiskammahoek (South Africa) -- Social conditions , Keiskammahoek (South Africa) -- Economic conditions , Power (Social sciences) -- South Africa -- Keiskammahoek
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2573 , http://hdl.handle.net/10962/d1002426 , Keiskammahoek (South Africa) -- Social conditions , Keiskammahoek (South Africa) -- Economic conditions , Power (Social sciences) -- South Africa -- Keiskammahoek
- Description: Much of the available documentation, and the multiple oral testimonies collected for this thesis agree that the most important changes that have occurred in Keiskammahoek district over the past half century resulted from the implementation of the government's conservationist policy known as betterment. The work is thus dominated by a wideranging look at betterment in Keiskammahoek The thesis is arranged chronologically, and each of the successive periods designated is analysed in terms of power. The first period considered is c.1920-c.1936; this was the time during which betterment policy was conceived. The key question that is posed here is why the policy was formed. Foucault's idea of power/knowledge features prominently in answering this question. For all of the remaining periods a conspicuously ,important power relation (unequal relationship) is chosen, and the analyses consist of plotting the histories of the various relations. The first of these periods is that which preceded the implementation of betterment in the district, i.e. c.1936-1960. Since multi-form resistance against betterment characterised this period, the power relation considered is that between the state and the various communities of Keiskammahoek. Next, attention is given to the actual implementation of betterment in the district. Because betterment affected locations in which land was held communally so differently from locations in which land was held under title, these two categories of location are analysed separately. In communal locations, a power relation spawned by betterment that has come to dominate life is that between village neighbours. In the other category of location, betterment has often further differentiated the power relation between title-deed holders and non title-deed holders. The thesis is not exclusively devoted to betterment. The 1970s saw many people being forcibly removed to Keiskammahoek. The final section of the work examines these events in relation to the changing economy of South Africa. In this section the power relation that is deemed important is that between the employed and unemployed The overall aim of the thesis then is to give an indication of the variety of forms or configurations of power that run through modernday Keiskammahoek.
- Full Text:
- Authors: Westaway, Ashley Frank Hurford
- Date: 1993
- Subjects: Keiskammahoek (South Africa) -- Social conditions , Keiskammahoek (South Africa) -- Economic conditions , Power (Social sciences) -- South Africa -- Keiskammahoek
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2573 , http://hdl.handle.net/10962/d1002426 , Keiskammahoek (South Africa) -- Social conditions , Keiskammahoek (South Africa) -- Economic conditions , Power (Social sciences) -- South Africa -- Keiskammahoek
- Description: Much of the available documentation, and the multiple oral testimonies collected for this thesis agree that the most important changes that have occurred in Keiskammahoek district over the past half century resulted from the implementation of the government's conservationist policy known as betterment. The work is thus dominated by a wideranging look at betterment in Keiskammahoek The thesis is arranged chronologically, and each of the successive periods designated is analysed in terms of power. The first period considered is c.1920-c.1936; this was the time during which betterment policy was conceived. The key question that is posed here is why the policy was formed. Foucault's idea of power/knowledge features prominently in answering this question. For all of the remaining periods a conspicuously ,important power relation (unequal relationship) is chosen, and the analyses consist of plotting the histories of the various relations. The first of these periods is that which preceded the implementation of betterment in the district, i.e. c.1936-1960. Since multi-form resistance against betterment characterised this period, the power relation considered is that between the state and the various communities of Keiskammahoek. Next, attention is given to the actual implementation of betterment in the district. Because betterment affected locations in which land was held communally so differently from locations in which land was held under title, these two categories of location are analysed separately. In communal locations, a power relation spawned by betterment that has come to dominate life is that between village neighbours. In the other category of location, betterment has often further differentiated the power relation between title-deed holders and non title-deed holders. The thesis is not exclusively devoted to betterment. The 1970s saw many people being forcibly removed to Keiskammahoek. The final section of the work examines these events in relation to the changing economy of South Africa. In this section the power relation that is deemed important is that between the employed and unemployed The overall aim of the thesis then is to give an indication of the variety of forms or configurations of power that run through modernday Keiskammahoek.
- Full Text:
The geology of the Welkom Goldfield with special reference to the "A", "B" and Beatrix Reefs
- Authors: Dwyer, Gordon Bransby
- Date: 1993
- Subjects: Gold mines and mining -- South Africa -- Free State , Gold ores -- Geology -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4963 , http://hdl.handle.net/10962/d1005575 , Gold mines and mining -- South Africa -- Free State , Gold ores -- Geology -- South Africa
- Description: The first Witwatersrand gold deposits in the Orange Free State were discovered under younger cover rocks in the 1930's with the aid of drilling and geophysics. The Welkom gold deposits are found in the sedimentary rock sequences of the Central Rand Group, which represent unconformity bounded genetic packages. The structural configuration of the goldfield is one of a north to south trending synform that is split near it's axis by the De Bron and Homestead faults. The "B" Reef is a highly variable, erratically mineralised reef that lies on an unconformity at the base of the Spes Bona Formation. The "A" Reef Zone consists of several placers 1 including the "Reworked BPM" 1 the Witpan, the Uitsig, the Hanging Wall Grits and the Upper "A" Reef. The Beatrix Reef lies at the base of the Eldorado Formation on an unconformity surface overlying the Virginia Formation in the southern part of the Welkom Goldfield. The origin of gold in the Witwatersrand basin can be classified into the modified placer theory, the syngenetic theory and the epigenetic theory. From the distribution of basin edge unconformities it can be deduced that the Welkom fan depository was tectonically active on the western, southern and eastern margins during sedimentation. Palaeocurrent studies indicate that sediment was transported predominantly from the south and west. It is thought that the "B", "A" and Beatrix Reefs were all deposited in a braided stream environment. A multidisciplinary approach to ore evaluation of Witwatersrand deposits is considered to be the best method, where sedimentology, geostatistics and structural geology are used.
- Full Text:
- Authors: Dwyer, Gordon Bransby
- Date: 1993
- Subjects: Gold mines and mining -- South Africa -- Free State , Gold ores -- Geology -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4963 , http://hdl.handle.net/10962/d1005575 , Gold mines and mining -- South Africa -- Free State , Gold ores -- Geology -- South Africa
- Description: The first Witwatersrand gold deposits in the Orange Free State were discovered under younger cover rocks in the 1930's with the aid of drilling and geophysics. The Welkom gold deposits are found in the sedimentary rock sequences of the Central Rand Group, which represent unconformity bounded genetic packages. The structural configuration of the goldfield is one of a north to south trending synform that is split near it's axis by the De Bron and Homestead faults. The "B" Reef is a highly variable, erratically mineralised reef that lies on an unconformity at the base of the Spes Bona Formation. The "A" Reef Zone consists of several placers 1 including the "Reworked BPM" 1 the Witpan, the Uitsig, the Hanging Wall Grits and the Upper "A" Reef. The Beatrix Reef lies at the base of the Eldorado Formation on an unconformity surface overlying the Virginia Formation in the southern part of the Welkom Goldfield. The origin of gold in the Witwatersrand basin can be classified into the modified placer theory, the syngenetic theory and the epigenetic theory. From the distribution of basin edge unconformities it can be deduced that the Welkom fan depository was tectonically active on the western, southern and eastern margins during sedimentation. Palaeocurrent studies indicate that sediment was transported predominantly from the south and west. It is thought that the "B", "A" and Beatrix Reefs were all deposited in a braided stream environment. A multidisciplinary approach to ore evaluation of Witwatersrand deposits is considered to be the best method, where sedimentology, geostatistics and structural geology are used.
- Full Text:
The influence of contrasting freshwater inflows on the feeding ecology and food resources of zooplankton in two eastern Cape estuaries, South Africa
- Authors: Grange, Neil
- Date: 1993
- Subjects: Freshwater zooplankton -- Ecology -- South Africa Aquatic ecology -- Research -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5714 , http://hdl.handle.net/10962/d1005400
- Description: The trophodynamic implications of reduced freshwater inflow on the zooplankton of eastern Cape estuaries was investigated by a comparison of the community composition and standing stocks, grazing rates and food resources of zooplankton in two systems, the Kariega and the Great Fish estuaries, which are subject to contrasting freshwater inflow. The climate of South Africa is semi-arid, and the low rainfall, coupled with high evaporative loss, result in the region having one of the lowest conversions of rainfall to run-off in the world. In addition, many of the major rivers are extensively impounded, consequently, estuaries often experience prolonged periods of zero or reduced freshwater inflow. The amount of freshwater available for estuarine management in the future is expected to decline as the demand for domestic, agricultural and industrial use increases. The influence of climate, tidal amplitude and wave action are essentially constant, consequently, the individual characteristics of an estuary are determined largely by the indirect influences of catchment size and regulation. Estuaries along the eastern Cape coast range from negative hypersaline systems, to positive systems in which a salinity gradient is well established. The Kariega estuary is a homogeneous marine estuary as a result of minimal freshwater inflow, whereas the Great Fish estuary receives sustained freshwater inflow and is partially-stratified. The quality and quantity of particulate food resources for suspension-feeders depended to a large extent on the allochthonous import of material associated with freshwater inflow. Nutrients, rather than light penetration of the watercolumn are the major factor limiting phytoplankton standing stocks. In the Kariega estuary, phytoplankton standing stocks were low (up to 1.0 μg l⁻¹) and the estuary is classified as oligotrophic. Correlation analyses indicated that lower quality detritus, originating from fringing macrophytes, may contribute substantially to suspended particulate organic material. Phytoplankton food resources were considerably higher in the Great Fish estuary (up to 21.8 μg ⁻¹) which is classified as mesotrophic/eutrophic, and correlation analyses indicated that phytoplankton comprised the dominant fraction of the particulate organic material. Although this suggested that the organic material was of a higher quality, the seston was "masked" by a higher suspended inorganic load. Consequently, the organic fraction comprised between 13 and 22% of total particulate material in the Great Fish estuary, compared with between 20 and 39% in the Kariega estuary. Food resources demonstrated a fairly uniform distribution along the length of the Kariega estuary and exhibited a slight seasonal increase during warmer months. By contrast, the point source influence of freshwater inflow resulted in a spatial gradient of food resources in the Great Fish estuary with higher values recorded towards the upper reaches. There was evidence that higher concentrations of particulate material in the upper reaches are also a consequence of hydrodynamic trapping. There was no marked seasonal pattern in the availability of food resources which were generally elevated in response to sporadic pulses of freshwater inflow. Tidal currents were responsible for elevating suspended food resources by re-suspension of material from the sediments. This effect was probably of greater importance in the Kariega estuary where food resources were generally limiting. In the Kariega estuary, the zooplankton community was dominated by calanoid copepods of the genera Acartia and Pseudodiaptomus. However, in the Great Fish estuary, the community was dominated by the mysid Mesopodopsis siabberi, and the calanoid P. hessei. Community biomass generally reflected the trophic status of the estuary. The mean seasonal biomass recorded in the Kariega estuary was 38 mg m⁻³ compared with 1597 mg m⁻³ in the Great Fish estuary. Greater spatial variability in community biomass was evident in the Great Fish estuary, partly in response to the food resource gradient, but also due to the inability of the mysid shrimps, which dominated the community biomass, to penetrate the lower salinity water of the upper reaches. Zooplankton in the Kariega estuary demonstrated a seasonal pattern of abundance whereas in the Great Fish estuary, community biomass was elevated in response to sporadic pulses of freshwater inflow. Grazing rates, measured in situ using a modified Gliwicz-Haney chamber, indicated that the zooplankton communities were capable of "clearing" substantial proportions of the watercolumn at certain times of the year. The pattern of grazing pressure over a diel cycle was examined in relation to the diel vertical migration movements of the zooplankton. Higher nighttime grazing rates were generally associated with the greater abundance of zooplankton resulting from the movement of zooplankton into the watercolumn after dusk, and their return to the sediments at dawn. Seasonal estimates of diel grazing pressure, extrapolated from daytime and nighttime feeding rates, indicated that the zooplankton "cleared" up to 40% of the watercolumn in a day in the Kariega estuary, and up to 120% d⁻¹ in the Great Fish estuary. However, values of around 25% d⁻¹ in the Kariega estuary, and 50 to 80% d⁻¹ in the Great Fish estuary, were not uncommon. Multiple regression analyses were used in an attempt to explain the influence of environmental factors on the variation in in situ grazing rates. These attempts were largely unsuccessful and the possible reasons, as well as recommended improvements to the methods used, are discussed. Seston concentration in the estuaries was highly variable as a result of the effects of tidal re-suspension and freshwater inflow. Consequently, further laboratory-based experiments were carried out to examine the influence of seston concentration on the filtration rates of the dominant calanoid copepods. Results indicated that some of the unexplained variability in the community filtration rates may be attributed to differences in species-specific response to changes in seston concentration.
- Full Text:
- Authors: Grange, Neil
- Date: 1993
- Subjects: Freshwater zooplankton -- Ecology -- South Africa Aquatic ecology -- Research -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5714 , http://hdl.handle.net/10962/d1005400
- Description: The trophodynamic implications of reduced freshwater inflow on the zooplankton of eastern Cape estuaries was investigated by a comparison of the community composition and standing stocks, grazing rates and food resources of zooplankton in two systems, the Kariega and the Great Fish estuaries, which are subject to contrasting freshwater inflow. The climate of South Africa is semi-arid, and the low rainfall, coupled with high evaporative loss, result in the region having one of the lowest conversions of rainfall to run-off in the world. In addition, many of the major rivers are extensively impounded, consequently, estuaries often experience prolonged periods of zero or reduced freshwater inflow. The amount of freshwater available for estuarine management in the future is expected to decline as the demand for domestic, agricultural and industrial use increases. The influence of climate, tidal amplitude and wave action are essentially constant, consequently, the individual characteristics of an estuary are determined largely by the indirect influences of catchment size and regulation. Estuaries along the eastern Cape coast range from negative hypersaline systems, to positive systems in which a salinity gradient is well established. The Kariega estuary is a homogeneous marine estuary as a result of minimal freshwater inflow, whereas the Great Fish estuary receives sustained freshwater inflow and is partially-stratified. The quality and quantity of particulate food resources for suspension-feeders depended to a large extent on the allochthonous import of material associated with freshwater inflow. Nutrients, rather than light penetration of the watercolumn are the major factor limiting phytoplankton standing stocks. In the Kariega estuary, phytoplankton standing stocks were low (up to 1.0 μg l⁻¹) and the estuary is classified as oligotrophic. Correlation analyses indicated that lower quality detritus, originating from fringing macrophytes, may contribute substantially to suspended particulate organic material. Phytoplankton food resources were considerably higher in the Great Fish estuary (up to 21.8 μg ⁻¹) which is classified as mesotrophic/eutrophic, and correlation analyses indicated that phytoplankton comprised the dominant fraction of the particulate organic material. Although this suggested that the organic material was of a higher quality, the seston was "masked" by a higher suspended inorganic load. Consequently, the organic fraction comprised between 13 and 22% of total particulate material in the Great Fish estuary, compared with between 20 and 39% in the Kariega estuary. Food resources demonstrated a fairly uniform distribution along the length of the Kariega estuary and exhibited a slight seasonal increase during warmer months. By contrast, the point source influence of freshwater inflow resulted in a spatial gradient of food resources in the Great Fish estuary with higher values recorded towards the upper reaches. There was evidence that higher concentrations of particulate material in the upper reaches are also a consequence of hydrodynamic trapping. There was no marked seasonal pattern in the availability of food resources which were generally elevated in response to sporadic pulses of freshwater inflow. Tidal currents were responsible for elevating suspended food resources by re-suspension of material from the sediments. This effect was probably of greater importance in the Kariega estuary where food resources were generally limiting. In the Kariega estuary, the zooplankton community was dominated by calanoid copepods of the genera Acartia and Pseudodiaptomus. However, in the Great Fish estuary, the community was dominated by the mysid Mesopodopsis siabberi, and the calanoid P. hessei. Community biomass generally reflected the trophic status of the estuary. The mean seasonal biomass recorded in the Kariega estuary was 38 mg m⁻³ compared with 1597 mg m⁻³ in the Great Fish estuary. Greater spatial variability in community biomass was evident in the Great Fish estuary, partly in response to the food resource gradient, but also due to the inability of the mysid shrimps, which dominated the community biomass, to penetrate the lower salinity water of the upper reaches. Zooplankton in the Kariega estuary demonstrated a seasonal pattern of abundance whereas in the Great Fish estuary, community biomass was elevated in response to sporadic pulses of freshwater inflow. Grazing rates, measured in situ using a modified Gliwicz-Haney chamber, indicated that the zooplankton communities were capable of "clearing" substantial proportions of the watercolumn at certain times of the year. The pattern of grazing pressure over a diel cycle was examined in relation to the diel vertical migration movements of the zooplankton. Higher nighttime grazing rates were generally associated with the greater abundance of zooplankton resulting from the movement of zooplankton into the watercolumn after dusk, and their return to the sediments at dawn. Seasonal estimates of diel grazing pressure, extrapolated from daytime and nighttime feeding rates, indicated that the zooplankton "cleared" up to 40% of the watercolumn in a day in the Kariega estuary, and up to 120% d⁻¹ in the Great Fish estuary. However, values of around 25% d⁻¹ in the Kariega estuary, and 50 to 80% d⁻¹ in the Great Fish estuary, were not uncommon. Multiple regression analyses were used in an attempt to explain the influence of environmental factors on the variation in in situ grazing rates. These attempts were largely unsuccessful and the possible reasons, as well as recommended improvements to the methods used, are discussed. Seston concentration in the estuaries was highly variable as a result of the effects of tidal re-suspension and freshwater inflow. Consequently, further laboratory-based experiments were carried out to examine the influence of seston concentration on the filtration rates of the dominant calanoid copepods. Results indicated that some of the unexplained variability in the community filtration rates may be attributed to differences in species-specific response to changes in seston concentration.
- Full Text:
The influence of geological, genetic and economic factors on the ore reserve estimation of Kwaggashoek east iron ore deposit
- Authors: Latorre-Muzzio, Gina
- Date: 1993
- Subjects: Iron ores -- Geology -- South Africa , Geology -- South Africa -- Transvaal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4972 , http://hdl.handle.net/10962/d1005584 , Iron ores -- Geology -- South Africa , Geology -- South Africa -- Transvaal
- Description: Tectonics plays an important role in the genesis and subsequent mlnlng development of the Kwaggashoek East ore body. Lithological key units control the effectiveness of the ore forming processes, affecting the in situ ore reserve, The Kwaggashoek East deposit is the product of primary and secondary processes. A genetic model focussed on the source, migration and deposition of iron suggests a possible original source of iron as the product of very dilute hydrothermal input into deep ocean waters, with subsequent migration through structural conduits. Supergene processes account for the upgrading of the ore and the phosphorus redistribution. A good correlation between samples in a preliminary geostatistical study reflects the effectiveness of this process in the high grade ore zone. A broad overview of the economic issues which affect the commercialization of iron, indicates a balanced supply-demand situation for the five next years. The reserve estimation procedure requires accurate scientific terminology and appropriate methodology. Documentation is essential and should be detailed enough to allow for future reassessment. The results of three estimation methods in Kwaggashoek East differ by less than 5%. The accuracy of the final results depends more on geological interpretation and assumptions than on the method applied. Although optimization of grade and tonnage in the Kwaggashoek East deposit seems to be met with the actual cut-off grade used in the Thabazimbi mine district, the grade-quality concept introduced in this thesis indicates a decrease in the estimated reserves for the deposit
- Full Text:
- Authors: Latorre-Muzzio, Gina
- Date: 1993
- Subjects: Iron ores -- Geology -- South Africa , Geology -- South Africa -- Transvaal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4972 , http://hdl.handle.net/10962/d1005584 , Iron ores -- Geology -- South Africa , Geology -- South Africa -- Transvaal
- Description: Tectonics plays an important role in the genesis and subsequent mlnlng development of the Kwaggashoek East ore body. Lithological key units control the effectiveness of the ore forming processes, affecting the in situ ore reserve, The Kwaggashoek East deposit is the product of primary and secondary processes. A genetic model focussed on the source, migration and deposition of iron suggests a possible original source of iron as the product of very dilute hydrothermal input into deep ocean waters, with subsequent migration through structural conduits. Supergene processes account for the upgrading of the ore and the phosphorus redistribution. A good correlation between samples in a preliminary geostatistical study reflects the effectiveness of this process in the high grade ore zone. A broad overview of the economic issues which affect the commercialization of iron, indicates a balanced supply-demand situation for the five next years. The reserve estimation procedure requires accurate scientific terminology and appropriate methodology. Documentation is essential and should be detailed enough to allow for future reassessment. The results of three estimation methods in Kwaggashoek East differ by less than 5%. The accuracy of the final results depends more on geological interpretation and assumptions than on the method applied. Although optimization of grade and tonnage in the Kwaggashoek East deposit seems to be met with the actual cut-off grade used in the Thabazimbi mine district, the grade-quality concept introduced in this thesis indicates a decrease in the estimated reserves for the deposit
- Full Text:
The integration of academic skills/support programmes into university department structures: a case study in the sociology of education
- Authors: Drewett, Michael
- Date: 1993
- Subjects: Education, Higher -- South Africa , Compensatory education -- South Africa , Education, Higher , Education -- Philosophy , Rhodes University. Academic Development Programme
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3327 , http://hdl.handle.net/10962/d1003115
- Description: This research focuses on the extent to which the Rhodes University Academic Skills Programme (ASP), now known as the Academic Development Programme, is able to act as an agent of progressive change within Rhodes University. In so doing it concentrates on the potential of the strategy of integrated academic development for dealing with the academic needs of university students within the context of South Africa as a society in transition. The candidate considers the inability of structuralist educational theory to account for the potential of human agency at the site of formal education. It is shown that structuralist theories provide deterministic and pessimistic accounts of the role of institutions of formal education. In support of this contention this study explores the history of ASP at Rhodes University, demonstrating that significant change in student academic development has already taken place. ASP has contributed to change within the said University through challenging traditional notions of academic development. This thesis suggests that the non-structuralist critical theory of Jurgen Habermas provides a more holistic account of ASP than do structuralist theories of formal education. Through the incorporation of Habermas's theory of communicative action a process of critical integration is explored, showing that a strategy of integrated academic development has the potential to involve all those who have an interest in university education through a process of rational discourse. This potential is strengthened by the fact that many students and staff have expressed an awareness of the need for an integrated academic development strategy. This thesis subsequently explores the possibility of there being a process of democratic and rational discourse which could lead to a progressive integration programme in the Rhodes University Department of Sociology and Industrial Sociology. This thesis stresses the contested nature of the integration process within departments. It is indicated that Habermas's critical theory is able to account for the changes which have taken place in the past and which are presently under way. It is argued that it not possible to predict future outcomes, but that if ASP pursues a process of rational discourse, it will indeed be able to stimulate a critical integrative approach to academic development in the Rhodes University Department of Sociology and Industrial Sociology.
- Full Text:
- Authors: Drewett, Michael
- Date: 1993
- Subjects: Education, Higher -- South Africa , Compensatory education -- South Africa , Education, Higher , Education -- Philosophy , Rhodes University. Academic Development Programme
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3327 , http://hdl.handle.net/10962/d1003115
- Description: This research focuses on the extent to which the Rhodes University Academic Skills Programme (ASP), now known as the Academic Development Programme, is able to act as an agent of progressive change within Rhodes University. In so doing it concentrates on the potential of the strategy of integrated academic development for dealing with the academic needs of university students within the context of South Africa as a society in transition. The candidate considers the inability of structuralist educational theory to account for the potential of human agency at the site of formal education. It is shown that structuralist theories provide deterministic and pessimistic accounts of the role of institutions of formal education. In support of this contention this study explores the history of ASP at Rhodes University, demonstrating that significant change in student academic development has already taken place. ASP has contributed to change within the said University through challenging traditional notions of academic development. This thesis suggests that the non-structuralist critical theory of Jurgen Habermas provides a more holistic account of ASP than do structuralist theories of formal education. Through the incorporation of Habermas's theory of communicative action a process of critical integration is explored, showing that a strategy of integrated academic development has the potential to involve all those who have an interest in university education through a process of rational discourse. This potential is strengthened by the fact that many students and staff have expressed an awareness of the need for an integrated academic development strategy. This thesis subsequently explores the possibility of there being a process of democratic and rational discourse which could lead to a progressive integration programme in the Rhodes University Department of Sociology and Industrial Sociology. This thesis stresses the contested nature of the integration process within departments. It is indicated that Habermas's critical theory is able to account for the changes which have taken place in the past and which are presently under way. It is argued that it not possible to predict future outcomes, but that if ASP pursues a process of rational discourse, it will indeed be able to stimulate a critical integrative approach to academic development in the Rhodes University Department of Sociology and Industrial Sociology.
- Full Text:
The interactive effects of light, temperature and CO[subscript 2]/O[subscript 2] ratios on photosynthesis in Coix lachryma-jobi L
- Mjwara, Jabulani M, Botha, Christiaan E J
- Authors: Mjwara, Jabulani M , Botha, Christiaan E J
- Date: 1993
- Language: English
- Type: Article
- Identifier: vital:6527 , http://hdl.handle.net/10962/d1005961
- Description: A portable infra-red gas analyzer was used to investigate the interactive effects of light, temperature, and CO[subscript 2]/O[subscript 2] ratios under controlled environmental conditions in an attempt to model gas exchange characteristics of Coix lachryma-jobi L. Plotting light response curves as a function of temperature (20, 25, 30 and 35 degrees C) revealed no sign of light saturation even at a photosynthetic photon flux density (PPFD) close to 2000 µmol m[superscript -2]s[superscript -1]. High net assimilation rates (A) of approximately 24 µmol CO[subscript 2] m[superscript -2]s[superscript -1] were realized at 30-35 degrees C. Assimilation (A) versus internal CO[subscript 2] partial pressure Ci curves showed a steep rise in A with increase in C[subscript i] but saturated at approximately 150 µl[superscript -1] and the effect was similar in either the absence or presence of O[subscript 2], under all temperature regimes. C. lachryma-jobi exhibited low CO[subscript 2] compensation points (Γ*) between 0 and 10 µl[superscript -1] at either 0 or 21% O[subscript 2]. The slopes of double reciprocal plots of 1/A versus 1/C[subscript i], were nearly identical and crossed the y-intercept at almost identical points under all O[subscript 2] concentrations. This data indicated that there was no apparent O[subscript 2] inhibition and that the apparent inhibitor constant (K[subscript i]) for O[subscript 2] at the site of carboxylation did not change with an increase in [O[subscript 2]] from 0 to 21%. These observations were further confirmed by results obtained from the analysis of apparent carboxylation efficiency where no inhibition of A with increase of [O[subscript 2]] occurred. These characteristics are thus consistent with typical features of C[subscript 4] photosynthesis.
- Full Text: false
- Authors: Mjwara, Jabulani M , Botha, Christiaan E J
- Date: 1993
- Language: English
- Type: Article
- Identifier: vital:6527 , http://hdl.handle.net/10962/d1005961
- Description: A portable infra-red gas analyzer was used to investigate the interactive effects of light, temperature, and CO[subscript 2]/O[subscript 2] ratios under controlled environmental conditions in an attempt to model gas exchange characteristics of Coix lachryma-jobi L. Plotting light response curves as a function of temperature (20, 25, 30 and 35 degrees C) revealed no sign of light saturation even at a photosynthetic photon flux density (PPFD) close to 2000 µmol m[superscript -2]s[superscript -1]. High net assimilation rates (A) of approximately 24 µmol CO[subscript 2] m[superscript -2]s[superscript -1] were realized at 30-35 degrees C. Assimilation (A) versus internal CO[subscript 2] partial pressure Ci curves showed a steep rise in A with increase in C[subscript i] but saturated at approximately 150 µl[superscript -1] and the effect was similar in either the absence or presence of O[subscript 2], under all temperature regimes. C. lachryma-jobi exhibited low CO[subscript 2] compensation points (Γ*) between 0 and 10 µl[superscript -1] at either 0 or 21% O[subscript 2]. The slopes of double reciprocal plots of 1/A versus 1/C[subscript i], were nearly identical and crossed the y-intercept at almost identical points under all O[subscript 2] concentrations. This data indicated that there was no apparent O[subscript 2] inhibition and that the apparent inhibitor constant (K[subscript i]) for O[subscript 2] at the site of carboxylation did not change with an increase in [O[subscript 2]] from 0 to 21%. These observations were further confirmed by results obtained from the analysis of apparent carboxylation efficiency where no inhibition of A with increase of [O[subscript 2]] occurred. These characteristics are thus consistent with typical features of C[subscript 4] photosynthesis.
- Full Text: false
The journal of the Reverend William Impey, 1838-1847 : a critical study of his work and theology
- Authors: Owen, David Rhys
- Date: 1993
- Subjects: Impey, William, 1818-1896 Methodist Church of Southern Africa -- Clergy -- Biography Methodist Church -- Missions Missionaries -- Biography
- Language: English
- Type: Thesis , Masters , MTh
- Identifier: vital:1243 , http://hdl.handle.net/10962/d1009691
- Description: William Impey (1818-1896) came to South Africa as a Wesleyan Methodist Missionary in 1839. He held various missionary and colonial appointments until 1860 when he succeeded William Shaw as Chairman of the Albany and Kaffraria District and General Superintendent of Wesleyan Methodist Missions in South-East Africa. Impey's major contribution was in the provision of education for the indigenous peoples of this region, especially as President of Healdtown (1868-1878). This institution eventually became one of the most highly thought of mission education academies in South Africa. To date little has been known of the life and work of William Impey despite his senior position in South African Wesleyan Methodism. J Whiteside's History of the Wesleyan Methodist Church of South Africa, the last comprehensive history of South African Methodism, published in 1906, only devotes a few lines to Impey. He does however make further reference to Impey's work in his section on education. The Methodist Archive at Manchester University, which contains the personal records of all 19th century Wesleyan Methodist ministers, also has very little information about Impey. The reason for this relative lack of information is that he resigned from the Wesleyan Methodist Church in 1878 on doctrinal grounds. Impey came under the influence of 19th century liberal theology and eventually drew the conclusion that he could no longer accept the doctrine of 'eternal punishment'. He believed that the only honest thing for him to do was to resign from the Wesleyan Methodist Church, which he believed required its ministers to adhere to this doctrine. He was accepted for ordination by the Anglican Church and served as a deacon in 1878 and then as a priest until his death in 1896. Impey's journal affords the reader an opportunity to have a glimpse into what life was like for a 19th century missionary living and working in South Africa. Perhaps its particular value lies in the many detailed entries Impey made about his personal spiritual experiences. The aim of this thesis is to place the life's work of William Impey in its historical and theological context in the belief that this will enable us better to understand the 19th century missionaries. It is hoped that this study will make a further contribution to our understanding of both 19th century missionaries and the times in which they lived and worked.
- Full Text:
- Authors: Owen, David Rhys
- Date: 1993
- Subjects: Impey, William, 1818-1896 Methodist Church of Southern Africa -- Clergy -- Biography Methodist Church -- Missions Missionaries -- Biography
- Language: English
- Type: Thesis , Masters , MTh
- Identifier: vital:1243 , http://hdl.handle.net/10962/d1009691
- Description: William Impey (1818-1896) came to South Africa as a Wesleyan Methodist Missionary in 1839. He held various missionary and colonial appointments until 1860 when he succeeded William Shaw as Chairman of the Albany and Kaffraria District and General Superintendent of Wesleyan Methodist Missions in South-East Africa. Impey's major contribution was in the provision of education for the indigenous peoples of this region, especially as President of Healdtown (1868-1878). This institution eventually became one of the most highly thought of mission education academies in South Africa. To date little has been known of the life and work of William Impey despite his senior position in South African Wesleyan Methodism. J Whiteside's History of the Wesleyan Methodist Church of South Africa, the last comprehensive history of South African Methodism, published in 1906, only devotes a few lines to Impey. He does however make further reference to Impey's work in his section on education. The Methodist Archive at Manchester University, which contains the personal records of all 19th century Wesleyan Methodist ministers, also has very little information about Impey. The reason for this relative lack of information is that he resigned from the Wesleyan Methodist Church in 1878 on doctrinal grounds. Impey came under the influence of 19th century liberal theology and eventually drew the conclusion that he could no longer accept the doctrine of 'eternal punishment'. He believed that the only honest thing for him to do was to resign from the Wesleyan Methodist Church, which he believed required its ministers to adhere to this doctrine. He was accepted for ordination by the Anglican Church and served as a deacon in 1878 and then as a priest until his death in 1896. Impey's journal affords the reader an opportunity to have a glimpse into what life was like for a 19th century missionary living and working in South Africa. Perhaps its particular value lies in the many detailed entries Impey made about his personal spiritual experiences. The aim of this thesis is to place the life's work of William Impey in its historical and theological context in the belief that this will enable us better to understand the 19th century missionaries. It is hoped that this study will make a further contribution to our understanding of both 19th century missionaries and the times in which they lived and worked.
- Full Text:
The Kinetic-Tree-House-Person drawing test as a diagnostic instrument in assessment of sexually abused children and monitoring the effects of group play therapy
- Authors: Donaldson, Marilyn Ann
- Date: 1993
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/193140 , vital:45302
- Description: This research project was developed from the idea that children's drawings reflect both their internal emotional lives and their external lived worlds. The subjects of the project were sexually abused children referred to Fort England Hospital during the first half of 1992. The Kinetic-Tree-House-Person projective drawing test was used as an instrument of assessment in conjunction with the Maudsley Child Psychiatric interview technique. Indications of the effects of sexual abuse were sought in drawing tests administered before and after interventions of ten sessions of group play therapy. Drawing tests were also administered to a control group of children. The research project explored the effectiveness of group play therapy interventions through comparison of pre intervention and post intervention drawings. The rationale for this project was the high incidence of rape and sexual abuse of prepubescent black young women in the Eastern Cape particularly, and in South Africa generally. There is need for both assessments of screening instruments and validation of therapeutic interventions if this problem is to be addressed adequately. , Thesis (MA) -- Faculty of Humanities, Psychology, 1993
- Full Text:
- Authors: Donaldson, Marilyn Ann
- Date: 1993
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/193140 , vital:45302
- Description: This research project was developed from the idea that children's drawings reflect both their internal emotional lives and their external lived worlds. The subjects of the project were sexually abused children referred to Fort England Hospital during the first half of 1992. The Kinetic-Tree-House-Person projective drawing test was used as an instrument of assessment in conjunction with the Maudsley Child Psychiatric interview technique. Indications of the effects of sexual abuse were sought in drawing tests administered before and after interventions of ten sessions of group play therapy. Drawing tests were also administered to a control group of children. The research project explored the effectiveness of group play therapy interventions through comparison of pre intervention and post intervention drawings. The rationale for this project was the high incidence of rape and sexual abuse of prepubescent black young women in the Eastern Cape particularly, and in South Africa generally. There is need for both assessments of screening instruments and validation of therapeutic interventions if this problem is to be addressed adequately. , Thesis (MA) -- Faculty of Humanities, Psychology, 1993
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The microbial production of polyphenol oxidase enzyme systems and their application in the treatment of phenolic wastewaters
- Authors: Goetsch, Patricia-Ann
- Date: 1993
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:21060 , http://hdl.handle.net/10962/6190
- Description: Phenolic compounds are a group of organic chemicals present in the wastewaters of many synthetic industrial processes. Due to their extreme toxicity to man and animals, and deleterious impact on the environment, a range of techniques exist for the effective treatment and disposal of these pollutants. Biological degradation using microbial enzymes presents a valuable alternative to conventional wastewater treatment systems. This research was therefore initiated to investigate the polyphenol oxidase enzyme system and the feasibility of its application for effluent treatment and studies in organic solvents. The enzyme system is widely distributed in nature, with Agaricus bisporus (the common mushroom) being the best known producer. Biochemical investigations of the enzyme system were therefore carried out using this extract. A screening programme was initiated to identify microbial polyphenol oxidase producers which could be cultured in liquid media, thereby enabling the production of large quantities of enzyme in fermentation systems. Extensive growth optimization and enzyme induction and optimization studies were carried out on selected cultures. A number of good producers were isolated, namely a bacterial culture designated AECI culture no. 26, Streptomyces antibioticus, Streptomyces glaucescens and a manipulated strain, Streptomyces lividans (pIJ702). Enzyme production by Agaricus bisporus mycelia was optimized in deep-liquid culture; enzyme extracts showed high phenol removal efficiencies. Streptomyces antibioticus, Streptomyces glaucescens, Streptomyces lividans (pIJ702) and AECI culture no. 26 whole cells were also investigated for phenol-removing ability in simulated phenolic effluents. The use of whole cells reduces enzyme inactivation and instability due to the protection of the enzyme system within the cell. All cultures showed improved removal efficiencies in phenolic growth media. These results strongly suggest their use for phenol removal in continuous systems.
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- Authors: Goetsch, Patricia-Ann
- Date: 1993
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:21060 , http://hdl.handle.net/10962/6190
- Description: Phenolic compounds are a group of organic chemicals present in the wastewaters of many synthetic industrial processes. Due to their extreme toxicity to man and animals, and deleterious impact on the environment, a range of techniques exist for the effective treatment and disposal of these pollutants. Biological degradation using microbial enzymes presents a valuable alternative to conventional wastewater treatment systems. This research was therefore initiated to investigate the polyphenol oxidase enzyme system and the feasibility of its application for effluent treatment and studies in organic solvents. The enzyme system is widely distributed in nature, with Agaricus bisporus (the common mushroom) being the best known producer. Biochemical investigations of the enzyme system were therefore carried out using this extract. A screening programme was initiated to identify microbial polyphenol oxidase producers which could be cultured in liquid media, thereby enabling the production of large quantities of enzyme in fermentation systems. Extensive growth optimization and enzyme induction and optimization studies were carried out on selected cultures. A number of good producers were isolated, namely a bacterial culture designated AECI culture no. 26, Streptomyces antibioticus, Streptomyces glaucescens and a manipulated strain, Streptomyces lividans (pIJ702). Enzyme production by Agaricus bisporus mycelia was optimized in deep-liquid culture; enzyme extracts showed high phenol removal efficiencies. Streptomyces antibioticus, Streptomyces glaucescens, Streptomyces lividans (pIJ702) and AECI culture no. 26 whole cells were also investigated for phenol-removing ability in simulated phenolic effluents. The use of whole cells reduces enzyme inactivation and instability due to the protection of the enzyme system within the cell. All cultures showed improved removal efficiencies in phenolic growth media. These results strongly suggest their use for phenol removal in continuous systems.
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The nature of olivine-rich cumulate rocks of the lower critical and lower zones of the northwestern Bushveld Complex
- Authors: Haikney, Susan Ann
- Date: 1993
- Subjects: Geochemistry -- South Africa , Igneous rocks -- South Africa , Olivine -- South Africa , Bushveld Complex (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4980 , http://hdl.handle.net/10962/d1005592 , Geochemistry -- South Africa , Igneous rocks -- South Africa , Olivine -- South Africa , Bushveld Complex (South Africa)
- Description: Boreholes NG1 and NG2 were drilled on the farm Nooitgedacht 406 KQ to intersect the lower Critical and lower Zones of the western Bushveld Complex. The aim of this study is to describe the textural features and chemical characteristics of the olivine-bearing rocks in the intersections, as determined by petrographic studies, XRF analysis and microprobe analysis. The olivine-bearing rocks are dunites, harzburgites and olivine pyroxenites. They comprise olivine and orthopyroxene, with minor chromite, clinopyroxene and plagioclase, and their textures vary between adcumulate, mesocumulate and poikilitic. The sequence intersected can be broadly correlated with that in the eastern Bushveld Complex. Of the whole-rock inter-element ratios, the MMF (MgO)/[MgO+FeO])ratio is the clearest indicator of cyclicity. The olivine-rich rocks are more primitive than the associated rocks, and seem to become more primitive with height in most intervals. The plagioclase in the olivine-bearing rocks is unusually sodic in corrposition, having a maximum Na₂0 content of 8.12%. A comparison of olivine and plagioclase compositions with those in other intrusions has revealed that the only other major intrusion with sodic plagioclase is the Kiglapait intrusion of Canada. In the Kiglapait intrusion the sodic plagioclase occurs in conjunction with fayalitic olivine as opposed to the forsteritic variety of this study. Chemical variations in the rocks sampled indicate that periodic replenishment of the magma from which the rocks crystallised must have occurred. In some of the olivine-bearing intervals where little fractionation is evident, replenishment seems to have been continuous. In other intervals fractionation appears to have continued uninterrupted for significant periods, prior to rejuvenation by fresh influxes of magma.
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- Authors: Haikney, Susan Ann
- Date: 1993
- Subjects: Geochemistry -- South Africa , Igneous rocks -- South Africa , Olivine -- South Africa , Bushveld Complex (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4980 , http://hdl.handle.net/10962/d1005592 , Geochemistry -- South Africa , Igneous rocks -- South Africa , Olivine -- South Africa , Bushveld Complex (South Africa)
- Description: Boreholes NG1 and NG2 were drilled on the farm Nooitgedacht 406 KQ to intersect the lower Critical and lower Zones of the western Bushveld Complex. The aim of this study is to describe the textural features and chemical characteristics of the olivine-bearing rocks in the intersections, as determined by petrographic studies, XRF analysis and microprobe analysis. The olivine-bearing rocks are dunites, harzburgites and olivine pyroxenites. They comprise olivine and orthopyroxene, with minor chromite, clinopyroxene and plagioclase, and their textures vary between adcumulate, mesocumulate and poikilitic. The sequence intersected can be broadly correlated with that in the eastern Bushveld Complex. Of the whole-rock inter-element ratios, the MMF (MgO)/[MgO+FeO])ratio is the clearest indicator of cyclicity. The olivine-rich rocks are more primitive than the associated rocks, and seem to become more primitive with height in most intervals. The plagioclase in the olivine-bearing rocks is unusually sodic in corrposition, having a maximum Na₂0 content of 8.12%. A comparison of olivine and plagioclase compositions with those in other intrusions has revealed that the only other major intrusion with sodic plagioclase is the Kiglapait intrusion of Canada. In the Kiglapait intrusion the sodic plagioclase occurs in conjunction with fayalitic olivine as opposed to the forsteritic variety of this study. Chemical variations in the rocks sampled indicate that periodic replenishment of the magma from which the rocks crystallised must have occurred. In some of the olivine-bearing intervals where little fractionation is evident, replenishment seems to have been continuous. In other intervals fractionation appears to have continued uninterrupted for significant periods, prior to rejuvenation by fresh influxes of magma.
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The nature of the oxidation products of dicyanoruthenium phthalocyanine in aqueous and non-aqueous solvents
- Authors: Nyokong, Tebello
- Date: 1993
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/295543 , vital:57352 , xlink:href="https://doi.org/10.1016/S0277-5387(00)81741-6"
- Description: The cyclic voltammetry of [(CN)2RuIIPc]2− in acetonitrile or dichloromethane shows two oxidation couples at E12 = 0.31 and 0.85 V (vs S.C.E.) in CH2Cl2 and E12 = 0.45 and 1.15 V (vs S.C.E.) in acetonitrile. The spectroelectrochemistry of [(CN)2RuIIPc]2− in these solvents showed that oxidations occur at the phthalocyanine ligand. K2[(CN)2RuIIPc] dissolves in water at pHs greater than 5. The cyclic voltammetry of this complex showed oxidation couples at 0.32 and 0.29 V (vs S.C.E.) for aqueous solutions containing sodium sulphate (0.1M) and for buffered solutions (pH = 9), respectively. Both cyclic voltammetry and controlled potential coulometry gave evidence of electrocrystallization of the oxidation product. Chemical oxidations of [(CN)2RuIIPc]2− in water also showed phthalocyanine ligand oxidation.
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- Authors: Nyokong, Tebello
- Date: 1993
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/295543 , vital:57352 , xlink:href="https://doi.org/10.1016/S0277-5387(00)81741-6"
- Description: The cyclic voltammetry of [(CN)2RuIIPc]2− in acetonitrile or dichloromethane shows two oxidation couples at E12 = 0.31 and 0.85 V (vs S.C.E.) in CH2Cl2 and E12 = 0.45 and 1.15 V (vs S.C.E.) in acetonitrile. The spectroelectrochemistry of [(CN)2RuIIPc]2− in these solvents showed that oxidations occur at the phthalocyanine ligand. K2[(CN)2RuIIPc] dissolves in water at pHs greater than 5. The cyclic voltammetry of this complex showed oxidation couples at 0.32 and 0.29 V (vs S.C.E.) for aqueous solutions containing sodium sulphate (0.1M) and for buffered solutions (pH = 9), respectively. Both cyclic voltammetry and controlled potential coulometry gave evidence of electrocrystallization of the oxidation product. Chemical oxidations of [(CN)2RuIIPc]2− in water also showed phthalocyanine ligand oxidation.
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The occurrence and development of' Siamese twins' and other abnormalities in Oreochromis mossambicus (Pisces, Cichlidae).
- Holden, Kathleen K, Bruton, Michael N
- Authors: Holden, Kathleen K , Bruton, Michael N
- Date: 1993
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447288 , vital:74602 , https://hdl.handle.net/10520/AJA00445096_605
- Description: Specimens from a clutch of Oreochromis mossambicus (Pisces, Cichlidae) exhibited a number of abnormalities such as enlarged pericardia, thin tube-like hearts, large depressions in the yolksac, spinal deformities and twinning. Descriptions of the differences in early ontogeny of two pairs of 'Siamese twins' over a period of at least eight days are given. The developmental pattern of the twins is similar to that of normal specimens but the developmental rate is slower in the twins. Possible explanations for these occurrences of polyembryony are given.
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- Authors: Holden, Kathleen K , Bruton, Michael N
- Date: 1993
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447288 , vital:74602 , https://hdl.handle.net/10520/AJA00445096_605
- Description: Specimens from a clutch of Oreochromis mossambicus (Pisces, Cichlidae) exhibited a number of abnormalities such as enlarged pericardia, thin tube-like hearts, large depressions in the yolksac, spinal deformities and twinning. Descriptions of the differences in early ontogeny of two pairs of 'Siamese twins' over a period of at least eight days are given. The developmental pattern of the twins is similar to that of normal specimens but the developmental rate is slower in the twins. Possible explanations for these occurrences of polyembryony are given.
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The political economy of educational provision in "white" commercial farming areas: findings from a case study conducted in the Ugie district in the north eastern Cape
- Authors: Stretton, Natasha Anne
- Date: 1993
- Subjects: Rural schools -- South Africa -- Northeastern Cape Province -- Ugie District , Education, Rural -- South Africa -- Ugie District , Black people -- Education -- South Africa Case studies , Education, Rural -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2833 , http://hdl.handle.net/10962/d1003043 , Rural schools -- South Africa -- Northeastern Cape Province -- Ugie District , Education, Rural -- South Africa -- Ugie District , Black people -- Education -- South Africa Case studies , Education, Rural -- South Africa -- Case studies
- Description: The under-provision of education for black South Africans has reached crisis proportions. While the education for black people in general is discriminatory and unequal, black rural people suffer further deprivations as there is a serious imbalance in the allocation of resources and the provision of education between urban and rural areas. Black education in the rural areas has been historically neglected for political and socio-economic reasons and, as a consequence, rural blacks have limited or no access to education. The purpose of this' study is to examine an aspect of rural education; viz: black farm schools in the 'white' commercial farming areas. It is argued that the provision of farm schools is intricately linked to the labour requirements of farmers and consequently farm schools cannot be understood independently from the social relations within commercial farming areas. The impact of local decision-making on the process of farm schooling is also significant and is an important aspect of this study. This thesis explores the political and socio-economic processes that have structured the provision of education within a small farming community, looking specifically at the effects of particular interest groups on the provision of black farm schools. The study operates on three levels. The first level provides a theoretical framework within which rural education can be better understood. It is argued that the bias towards urban areas is reflected in the current theoretical debates on the role and function of education ·in South Africa. As these theories are generally incapable of explaining rural education, an alternative model is proposed. As education cannot be understood in isolation from the rest of society, the second level of the study locates farm schooling within the broader political and socio-economic systems. This is done from two perspectives. The first perspective focuses on black education in general, tracing aspects of its development and highlighting the impact .of economic interests, white political control and black resistances to this development. The neglect of rural education is also contextualised historically and politically. The second perspective looks at rural education at a macro-level. The historical origins of the farm schools system and the effects of the relationship between agricultural capital and the state, and between farmers and farm workers on the process of farm schooling is examined. The final level of the study focuses on the micro-situation and provides an in-depth analysis of the political and socio-economic dynamics which have impacted upon the provision and process of farm schools within a specific farming community. In an attempt to understand the types of issues effecting farm schooling in this area, the attitudes of farmers, farm workers, farm- children and farm school teachers towards education are investigated. Four main issues were identified and are discussed in depth, viz: I) factors effecting the provision of black farm schools; 2) the relationship between education and the economic structure of the area; 3) the value of education; and 4) socio-economic factors effecting education in the area.
- Full Text:
- Authors: Stretton, Natasha Anne
- Date: 1993
- Subjects: Rural schools -- South Africa -- Northeastern Cape Province -- Ugie District , Education, Rural -- South Africa -- Ugie District , Black people -- Education -- South Africa Case studies , Education, Rural -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2833 , http://hdl.handle.net/10962/d1003043 , Rural schools -- South Africa -- Northeastern Cape Province -- Ugie District , Education, Rural -- South Africa -- Ugie District , Black people -- Education -- South Africa Case studies , Education, Rural -- South Africa -- Case studies
- Description: The under-provision of education for black South Africans has reached crisis proportions. While the education for black people in general is discriminatory and unequal, black rural people suffer further deprivations as there is a serious imbalance in the allocation of resources and the provision of education between urban and rural areas. Black education in the rural areas has been historically neglected for political and socio-economic reasons and, as a consequence, rural blacks have limited or no access to education. The purpose of this' study is to examine an aspect of rural education; viz: black farm schools in the 'white' commercial farming areas. It is argued that the provision of farm schools is intricately linked to the labour requirements of farmers and consequently farm schools cannot be understood independently from the social relations within commercial farming areas. The impact of local decision-making on the process of farm schooling is also significant and is an important aspect of this study. This thesis explores the political and socio-economic processes that have structured the provision of education within a small farming community, looking specifically at the effects of particular interest groups on the provision of black farm schools. The study operates on three levels. The first level provides a theoretical framework within which rural education can be better understood. It is argued that the bias towards urban areas is reflected in the current theoretical debates on the role and function of education ·in South Africa. As these theories are generally incapable of explaining rural education, an alternative model is proposed. As education cannot be understood in isolation from the rest of society, the second level of the study locates farm schooling within the broader political and socio-economic systems. This is done from two perspectives. The first perspective focuses on black education in general, tracing aspects of its development and highlighting the impact .of economic interests, white political control and black resistances to this development. The neglect of rural education is also contextualised historically and politically. The second perspective looks at rural education at a macro-level. The historical origins of the farm schools system and the effects of the relationship between agricultural capital and the state, and between farmers and farm workers on the process of farm schooling is examined. The final level of the study focuses on the micro-situation and provides an in-depth analysis of the political and socio-economic dynamics which have impacted upon the provision and process of farm schools within a specific farming community. In an attempt to understand the types of issues effecting farm schooling in this area, the attitudes of farmers, farm workers, farm- children and farm school teachers towards education are investigated. Four main issues were identified and are discussed in depth, viz: I) factors effecting the provision of black farm schools; 2) the relationship between education and the economic structure of the area; 3) the value of education; and 4) socio-economic factors effecting education in the area.
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The regulation of Serotonin N-acetyltransferase in the rat pineal gland
- Authors: Olivieri, Gianfranco
- Date: 1993
- Subjects: Serotonin -- Research Pineal gland Acetyltransferases
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4051 , http://hdl.handle.net/10962/d1004112
- Description: The synthesis of the pineal hormone, melatonin, is finely regulated by the pineal enzyme serotonin N-acetyltransferase (NAT). In the absence of light, the activity of NAT is markedly enhanced by the release of nor-adrenaline from sympathetic nerve endings in the pineal. Exposure of animals to light during darkness causes a sudden and dramatic reduction in the activity of NAT. The present study investigated a possible mechanism for this sudden decline in NAT activity. These investigations included the determination of the effects of S-adenosylmethionine (SAM), adenosine nucleotides and calcium on NAT activity. In vitro experiments using SAM showed that pineals pre-incubated with SAM prior to adrenergic stimulation did not significantly alter NAT activity or pineal indoleamine metabolism. However, measurement of pineal cyclic AMP showed that SAM exposure reduced the adrenergic-induced rise in pineal cyclic AMP. Experiments using adenosine 5'-monophosphate (5'-AMP) showed that this nucleotide enhanced both dark- and isoproterenol-induced NAT activity. Adenosine 5'-triphosphate (A TP), on the other hand, reduced NAT activity with a concomitant reduction in pineal indoleamine metabolism. Exposure of isoproterenol-stimulated pineals in organ culture to propranolol resulted in a marked rise in ATP and adenosine 5'-diphosphate (ADP) synthesis accompanied by a decline in 5'-AMP levels as compared with pineals treated with isoproterenol alone. This then implies that exposure of animals to light could cause a change in pineal nucleotide levels. Since nucleotide levels are also controlled by calcium, experiments were carried out to determine the effect of calcium on pineal NAT activity. These experiments showed that ethyleneglycol-bis-N,N,N,N,-tetraacetic acid (EGTA) enhanced NAT activity whilst calcium reduced the activity in pineal homogenates, implying that calcium may act directly on NAT to regulate its activity. Exposure of pineal glands in organ culture to the calmodulin antagonist R24571 caused a rise in pineal cyclic AMP levels with a concomitant decrease in cAMP-phosphodiesterase activity. This was, however, accompanied by a decline in Nacetyl serotonin and melatonin synthesis. These findings implicate a number of factors in the regulation of pineal NAT activity. A mechanism for the regulation of pineal NAT is proposed.
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- Authors: Olivieri, Gianfranco
- Date: 1993
- Subjects: Serotonin -- Research Pineal gland Acetyltransferases
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4051 , http://hdl.handle.net/10962/d1004112
- Description: The synthesis of the pineal hormone, melatonin, is finely regulated by the pineal enzyme serotonin N-acetyltransferase (NAT). In the absence of light, the activity of NAT is markedly enhanced by the release of nor-adrenaline from sympathetic nerve endings in the pineal. Exposure of animals to light during darkness causes a sudden and dramatic reduction in the activity of NAT. The present study investigated a possible mechanism for this sudden decline in NAT activity. These investigations included the determination of the effects of S-adenosylmethionine (SAM), adenosine nucleotides and calcium on NAT activity. In vitro experiments using SAM showed that pineals pre-incubated with SAM prior to adrenergic stimulation did not significantly alter NAT activity or pineal indoleamine metabolism. However, measurement of pineal cyclic AMP showed that SAM exposure reduced the adrenergic-induced rise in pineal cyclic AMP. Experiments using adenosine 5'-monophosphate (5'-AMP) showed that this nucleotide enhanced both dark- and isoproterenol-induced NAT activity. Adenosine 5'-triphosphate (A TP), on the other hand, reduced NAT activity with a concomitant reduction in pineal indoleamine metabolism. Exposure of isoproterenol-stimulated pineals in organ culture to propranolol resulted in a marked rise in ATP and adenosine 5'-diphosphate (ADP) synthesis accompanied by a decline in 5'-AMP levels as compared with pineals treated with isoproterenol alone. This then implies that exposure of animals to light could cause a change in pineal nucleotide levels. Since nucleotide levels are also controlled by calcium, experiments were carried out to determine the effect of calcium on pineal NAT activity. These experiments showed that ethyleneglycol-bis-N,N,N,N,-tetraacetic acid (EGTA) enhanced NAT activity whilst calcium reduced the activity in pineal homogenates, implying that calcium may act directly on NAT to regulate its activity. Exposure of pineal glands in organ culture to the calmodulin antagonist R24571 caused a rise in pineal cyclic AMP levels with a concomitant decrease in cAMP-phosphodiesterase activity. This was, however, accompanied by a decline in Nacetyl serotonin and melatonin synthesis. These findings implicate a number of factors in the regulation of pineal NAT activity. A mechanism for the regulation of pineal NAT is proposed.
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