What is the StreetNet Association?
- Authors: StreetNet Association
- Date: 2000
- Subjects: StreetNet Association
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/162148 , vital:40765
- Description: StreetNet was conceived by a network of individual vendors, activists, researchers and other people and institutions, who came together to look at how to increase the visibility, voice and bargaining power of street vendors throughout the world. StreetNet aims to promote the exchange of information and ideas on critical issues facing street vendors and on practical organizing and advocacy strategies. Through StreetNet, members should gain an understanding of the common problems of street vendors, develop new ideas for strengthening their organizing and advocacy efforts and join in international campaigns to promote policies and actions that can contribute to improving the lives of millions of street vendors.
- Full Text:
- Date Issued: 2000
- Authors: StreetNet Association
- Date: 2000
- Subjects: StreetNet Association
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/162148 , vital:40765
- Description: StreetNet was conceived by a network of individual vendors, activists, researchers and other people and institutions, who came together to look at how to increase the visibility, voice and bargaining power of street vendors throughout the world. StreetNet aims to promote the exchange of information and ideas on critical issues facing street vendors and on practical organizing and advocacy strategies. Through StreetNet, members should gain an understanding of the common problems of street vendors, develop new ideas for strengthening their organizing and advocacy efforts and join in international campaigns to promote policies and actions that can contribute to improving the lives of millions of street vendors.
- Full Text:
- Date Issued: 2000
Hidden presences in the spirituality of the amaXhosa of the Eastern Cape and the impact of Christianity on them
- Authors: Mtuze, P T
- Date: 2000
- Subjects: Spirituality -- South Africa -- Eastern Cape , Xhosa (African people) -- Religion , Missions -- South Africa -- Eastern Cape , Missionaries -- South Africa -- Eastern Cape , Christianity -- South Africa -- Eastern Cape -- History , Christianity and culture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTh
- Identifier: vital:1296 , http://hdl.handle.net/10962/d1015612
- Description: This thesis is an attempt to reopen the debate on the whole question of inculturation in Southern Africa especially in light of the fact that we are now in a multi-lingual and multi-religious state. It is an attempt to rehighlight the plight of the spirituality of the amaXhosa people over the last century when missionary and imperial onslaught relegated it to the doldrums. This plunged the amaXhosa in a crisis that has left them directionless, to put it mildly. This is said because the total onslaught destroyed their self-respect and their identity and begs the question as to whether their acceptability to God was contingent on renouncing their culture especially the hidden presences - Qamata, the living-dead and the notion of evil spirits. It is precisely because of these misconceptions regarding African culture and spirituality that the thesis has a strong expository and apologetic bias primarily aimed to address, and put into proper perspective, the significance of the Supreme Being, the living-dead and the evil spirits in African culture. The issues are discussed within the broader socio-historical context. The thesis is basically comparative in that it uses Celtic spirituality and the approach of the early Celtic church to the question of inculturation as its point of departure and as a foil against which the preposterous actions of the church in Africa should be seen. This comparative element is also reflected in the unmistakable `dichotomy’ of Western religion and African spirituality, or better still, lack of spirituality, that was so fervently maintained by the missionaries and the colonialists alike. It is for this reason that I concur with Chidester (1996:xiv) that `the study of religion must find itself, once again, on the frontier’. The study is informed by this approach right through. It should be stressed, from the outset, that the idea is not comparison in order to satisfy our curiosity, nor is it comparison in order to try to authenticate and vindicate the beleaguered African culture. The central idea of the study is to expose the absurdity of the policies of the past century in this regard. The myth of the pure blooded Christianity is confronted, if not exploded. Several examples of both inculturation and continuities between Christianity and other faiths such as the Jewish founding faith are given. The subtheme of cultural domination subtly spans the whole study culminating in Chapter Four where the blacks begin to appropriate some of the Christian symbols and the whites also begin to assimilate African concepts such as ubuntu.
- Full Text:
- Date Issued: 2000
- Authors: Mtuze, P T
- Date: 2000
- Subjects: Spirituality -- South Africa -- Eastern Cape , Xhosa (African people) -- Religion , Missions -- South Africa -- Eastern Cape , Missionaries -- South Africa -- Eastern Cape , Christianity -- South Africa -- Eastern Cape -- History , Christianity and culture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTh
- Identifier: vital:1296 , http://hdl.handle.net/10962/d1015612
- Description: This thesis is an attempt to reopen the debate on the whole question of inculturation in Southern Africa especially in light of the fact that we are now in a multi-lingual and multi-religious state. It is an attempt to rehighlight the plight of the spirituality of the amaXhosa people over the last century when missionary and imperial onslaught relegated it to the doldrums. This plunged the amaXhosa in a crisis that has left them directionless, to put it mildly. This is said because the total onslaught destroyed their self-respect and their identity and begs the question as to whether their acceptability to God was contingent on renouncing their culture especially the hidden presences - Qamata, the living-dead and the notion of evil spirits. It is precisely because of these misconceptions regarding African culture and spirituality that the thesis has a strong expository and apologetic bias primarily aimed to address, and put into proper perspective, the significance of the Supreme Being, the living-dead and the evil spirits in African culture. The issues are discussed within the broader socio-historical context. The thesis is basically comparative in that it uses Celtic spirituality and the approach of the early Celtic church to the question of inculturation as its point of departure and as a foil against which the preposterous actions of the church in Africa should be seen. This comparative element is also reflected in the unmistakable `dichotomy’ of Western religion and African spirituality, or better still, lack of spirituality, that was so fervently maintained by the missionaries and the colonialists alike. It is for this reason that I concur with Chidester (1996:xiv) that `the study of religion must find itself, once again, on the frontier’. The study is informed by this approach right through. It should be stressed, from the outset, that the idea is not comparison in order to satisfy our curiosity, nor is it comparison in order to try to authenticate and vindicate the beleaguered African culture. The central idea of the study is to expose the absurdity of the policies of the past century in this regard. The myth of the pure blooded Christianity is confronted, if not exploded. Several examples of both inculturation and continuities between Christianity and other faiths such as the Jewish founding faith are given. The subtheme of cultural domination subtly spans the whole study culminating in Chapter Four where the blacks begin to appropriate some of the Christian symbols and the whites also begin to assimilate African concepts such as ubuntu.
- Full Text:
- Date Issued: 2000
An assessment of the monkfish resource of Namibia
- Authors: Maartens, Lima
- Date: 2000
- Subjects: Lophius -- Namibia Lophius
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5231 , http://hdl.handle.net/10962/d1005074
- Description: Two monkfish species are caught off the coast of Namibia. These are Lophius vomerinus Valenciennes (1837) and L. vaillanti Regan (1903). L. vomerinus is the more abundant of the two and contributes approximately 99% to the total Namibian monkfish landings. The Namibian monkfish fishery is one of the largest and most valuable of its kind in the world. Two fishing fleets harvest the resource, viz. the monkfish and sole fleet and the hake directed fleet. In 1998 and 1999, monkfish were also harvested by one gillnet vessel that had an experimental right. In this study, the biology, abundance and exploitation patterns of monkfish were investigated and used as inputs into a stock assessment framework as a contribution towards the development of a management procedure for this species. Ground and sectioned otoliths and sectioned illicia were used to age Lophius vomerinus. The illicia provided more precise estimates of age, and growth was subsequently modelled using these age estimates. Growth in length and weight was best described by the threeparameter specialised von Bertalanffy model as Lt (cm TL) = 72.29 (1-e⁻°·¹⁴⁽t⁺°·³°⁾) and Wt (kg) = 3.96 (1-e⁻°·¹⁸⁽t⁺°·¹°⁾)²·⁹⁹ for males, and Lt (cm TL) = 111.98 (1-e⁻°·°⁸⁽t⁺°·³⁶⁾) and Wt (kg) = 6.92 (1-e⁻°·¹⁸⁽t⁻°·⁶⁴⁾)³·°³ for females. L. vomerinus is a slow-growing species with a life span in excess of 10 years. Reproductive activity was shown to occur throughout the year, with a slight peak during the winter months. The adult sex ratio of fish > 37 cm TL was biased towards females. Length-at-50% sexual maturity was attained at 32.1 cm TL for females and 23.7 cm TL for males. The rate of natural mortality was estimated at 0.15 year⁻¹, while fishing mortality rates during the 1970s, 1980s and 1990s were estimated at 0.01 year⁻¹, 0.04 year⁻¹ and 0.14 year⁻¹, respectively. Gillnetting for monkfish (300 mm stretched mesh) was highly efficient with a moderate bycatch of around 20% during the two years of operation. The main bycatch species were red crab, spider crab, squalid sharks, rays and Cape and Deep-water hake. The mean length of the monkfish caught in gillnets (67 cm TL) was significantly larger than the monkfish landed by the trawlers (38 cm TL) and less than 1% of immature fish were landed. Gillnet catch-per-unit-effort for monkfish fluctuated between 0.03 and 0.67 kg.day⁻¹.50 m net panel⁻¹, with a soak time of between one and sixteen days. More than 50% (by weight) of monkfish landed by monkfish and sole trawlers, consisted of fish below 36 cm TL. There was a significant increase in catches of juvenile monkfish during 1997 and 1998 in comparison to the period 1994 to 1996. Various types of rigid sorting grids were tested to release juvenile monkfish below 32 cm TL. Five grid designs were tested. These included an “Ex-it” grid with horizontal bars spaced at 55 mm, single grids with vertical and horizontal bars spaced at 55 mm and grids with circular openings of 110 and 168 mm in diameter. The most efficient design was the grid with circular openings of 110 cm in diameter, which ensured the escape of 66% of monkfish smaller than 31 cm TL. However, studies need to be undertaken to quantify the survival of released fish and to test the feasibility of using grid sorters on commercial monkfish and sole trawling gear. The monkfish resource was assessed by means of length cohort analyses, the Thompson and Bell predictive model and by way of a deterministic age-structured production modelling approach. The length cohort analysis models were sensitive to the rate of natural mortality and insensitive to changes in the terminal fishing mortality rate. These biases may, however, not be serious provided that estimates of abundance are used to reflect relative changes. Fish ranging between 26 and 59 cm TL are the most heavily exploited. The Thompson and Bell model predicted that the monkfish resource is exploited above MSY -levels and a reduction of approximately 40% in fishing effort would provide a higher yield. Yield-per-recruit ranged between 10 000 and 14 000 tonnes. Results should, however, be treated with caution, as the condition of steady state was not satisfied. The age-structured production model was tuned using trends in catch-per-unit-effort data, estimated by Generalised Linear Modeling, as well as relative abundance indices calculated from hake biomass surveys. The model was found to be sensitive to both the ‘steepness’ parameter h and estimates of natural mortality. The ‘depletion’ level of the monkfish resource is currently estimated to be 49%. Estimated coefficients of variation were high (> 63%) due to the lack of a consistent trend within the abundance indices to tune the model. Overall productivity of the monkfish resource was estimated to be approximately 16%, similar to other southern African demersal resources. Results of the risk analyses suggest that catches in excess of 7 000 tonnes may be unsustainable and that catches of 5 000 or 6 000 tonnes would decrease the risk of stock collapse and possibly lead to a recovery in the stock. Monkfish management strategies were reviewed and these were considered in relation to the results of this study. The following management recommendations were made: to follow the precautionary approach and implement a total allowable catch for monkfish; to implement rigid sorting grids as these would be the most appropriate way in which to reduce catches of juvenile monkfish; to restrict soak time, depth of operation and implement means to reduce ‘ghost fishing’ by gillnetting and finally, to develop a management procedure for Namibian monkfish with the main objective being the sustainable exploitation of the resource.
- Full Text:
- Date Issued: 2000
- Authors: Maartens, Lima
- Date: 2000
- Subjects: Lophius -- Namibia Lophius
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5231 , http://hdl.handle.net/10962/d1005074
- Description: Two monkfish species are caught off the coast of Namibia. These are Lophius vomerinus Valenciennes (1837) and L. vaillanti Regan (1903). L. vomerinus is the more abundant of the two and contributes approximately 99% to the total Namibian monkfish landings. The Namibian monkfish fishery is one of the largest and most valuable of its kind in the world. Two fishing fleets harvest the resource, viz. the monkfish and sole fleet and the hake directed fleet. In 1998 and 1999, monkfish were also harvested by one gillnet vessel that had an experimental right. In this study, the biology, abundance and exploitation patterns of monkfish were investigated and used as inputs into a stock assessment framework as a contribution towards the development of a management procedure for this species. Ground and sectioned otoliths and sectioned illicia were used to age Lophius vomerinus. The illicia provided more precise estimates of age, and growth was subsequently modelled using these age estimates. Growth in length and weight was best described by the threeparameter specialised von Bertalanffy model as Lt (cm TL) = 72.29 (1-e⁻°·¹⁴⁽t⁺°·³°⁾) and Wt (kg) = 3.96 (1-e⁻°·¹⁸⁽t⁺°·¹°⁾)²·⁹⁹ for males, and Lt (cm TL) = 111.98 (1-e⁻°·°⁸⁽t⁺°·³⁶⁾) and Wt (kg) = 6.92 (1-e⁻°·¹⁸⁽t⁻°·⁶⁴⁾)³·°³ for females. L. vomerinus is a slow-growing species with a life span in excess of 10 years. Reproductive activity was shown to occur throughout the year, with a slight peak during the winter months. The adult sex ratio of fish > 37 cm TL was biased towards females. Length-at-50% sexual maturity was attained at 32.1 cm TL for females and 23.7 cm TL for males. The rate of natural mortality was estimated at 0.15 year⁻¹, while fishing mortality rates during the 1970s, 1980s and 1990s were estimated at 0.01 year⁻¹, 0.04 year⁻¹ and 0.14 year⁻¹, respectively. Gillnetting for monkfish (300 mm stretched mesh) was highly efficient with a moderate bycatch of around 20% during the two years of operation. The main bycatch species were red crab, spider crab, squalid sharks, rays and Cape and Deep-water hake. The mean length of the monkfish caught in gillnets (67 cm TL) was significantly larger than the monkfish landed by the trawlers (38 cm TL) and less than 1% of immature fish were landed. Gillnet catch-per-unit-effort for monkfish fluctuated between 0.03 and 0.67 kg.day⁻¹.50 m net panel⁻¹, with a soak time of between one and sixteen days. More than 50% (by weight) of monkfish landed by monkfish and sole trawlers, consisted of fish below 36 cm TL. There was a significant increase in catches of juvenile monkfish during 1997 and 1998 in comparison to the period 1994 to 1996. Various types of rigid sorting grids were tested to release juvenile monkfish below 32 cm TL. Five grid designs were tested. These included an “Ex-it” grid with horizontal bars spaced at 55 mm, single grids with vertical and horizontal bars spaced at 55 mm and grids with circular openings of 110 and 168 mm in diameter. The most efficient design was the grid with circular openings of 110 cm in diameter, which ensured the escape of 66% of monkfish smaller than 31 cm TL. However, studies need to be undertaken to quantify the survival of released fish and to test the feasibility of using grid sorters on commercial monkfish and sole trawling gear. The monkfish resource was assessed by means of length cohort analyses, the Thompson and Bell predictive model and by way of a deterministic age-structured production modelling approach. The length cohort analysis models were sensitive to the rate of natural mortality and insensitive to changes in the terminal fishing mortality rate. These biases may, however, not be serious provided that estimates of abundance are used to reflect relative changes. Fish ranging between 26 and 59 cm TL are the most heavily exploited. The Thompson and Bell model predicted that the monkfish resource is exploited above MSY -levels and a reduction of approximately 40% in fishing effort would provide a higher yield. Yield-per-recruit ranged between 10 000 and 14 000 tonnes. Results should, however, be treated with caution, as the condition of steady state was not satisfied. The age-structured production model was tuned using trends in catch-per-unit-effort data, estimated by Generalised Linear Modeling, as well as relative abundance indices calculated from hake biomass surveys. The model was found to be sensitive to both the ‘steepness’ parameter h and estimates of natural mortality. The ‘depletion’ level of the monkfish resource is currently estimated to be 49%. Estimated coefficients of variation were high (> 63%) due to the lack of a consistent trend within the abundance indices to tune the model. Overall productivity of the monkfish resource was estimated to be approximately 16%, similar to other southern African demersal resources. Results of the risk analyses suggest that catches in excess of 7 000 tonnes may be unsustainable and that catches of 5 000 or 6 000 tonnes would decrease the risk of stock collapse and possibly lead to a recovery in the stock. Monkfish management strategies were reviewed and these were considered in relation to the results of this study. The following management recommendations were made: to follow the precautionary approach and implement a total allowable catch for monkfish; to implement rigid sorting grids as these would be the most appropriate way in which to reduce catches of juvenile monkfish; to restrict soak time, depth of operation and implement means to reduce ‘ghost fishing’ by gillnetting and finally, to develop a management procedure for Namibian monkfish with the main objective being the sustainable exploitation of the resource.
- Full Text:
- Date Issued: 2000
The growth and reproduction of Patella granularis (Mollusca : patellogastropoda) on the south-east coast of South Africa
- Authors: Vat, Laura Suzanne
- Date: 2000
- Subjects: Patellidae Limpets -- South Africa Mollusks -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5702 , http://hdl.handle.net/10962/d1005388
- Description: Aspects of the biology and ecology of Patella granularis were investigated along a 130km stretch of the south-east coast of South Africa. Distribution, biomass, density and population structure were investigated at seven localities. In addition, a more detailed study of the growth rate and reproductive biology of populations inhabiting three different substrata (aeolianite, quartzitic sandstone and mussel shells) was conducted. The genetic relationships between these three populations was also examined, as was the foraging behaviour of the limpets inhabiting an aeolianite and a quartzitic sandstone shore. Finally, differences in food availability on the different substrata were studied. On the south-east coast, P. granularis has a wide intertidal distribution, occurring from the upper Balanoid zone through to the Cochlear zone, where it is a common inhabitant of mussel shells. The mean shell length of P. granularis was found to decrease down the shore. The largest limpets (46.6 mm shell length) were found on an offshore island in Algoa Bay. At most localities investigated, the sex ratio deviated from a 1:1 ratio with more males than females being recorded on five shores. Both limpet density and biomass were lower on the south-east coast when compared to data published for west coast populations. On the south-east coast, both density and dry biomass were highest in the lower Balanoid zone. Allozyme electrophoresis indicated that P. granularis inhabiting aeolianite, quartzitic sandstone and mussel shells are all part of a single population. Extremely high genetic identity values (0.998), low levels of heterozygosities (0.035 - 0.061), low levels of polymorphisms (25% - 31%) and low FST values (0.021) all suggest that the three populations of P. granularis form a common breeding group, despite the high levels of phenotypic plasticity observed. On all shores, P. granularis was found to grow allometrically, increasing in shell height more rapidly than shell length. Estimation of the growth rate (determined by the Von Bertalanffy growth model) of P. granularis suggested that limpets inhabiting the mussel shells grew more slowly, and attained a smaller maximum size, than those inhabiting both the aeolianite and the quartzite (K = 0.25, 0.32 and 0.33 respectively; 27.12 mm, 31.89 mm and 32.96 mm respectively). Previous work has shown that west coast P. granularis grow more quickly (K = 0.7) and reach a greater size (. 40 mm). Translocation of limpets among sites suggested that limpet size in the mussel beds was spatially constrained. Shell microgrowth bands were deposited tidally, but could not be used for aging limpets due to shell erosion. Limpets from the aeolianite had the greatest reproductive fitness, producing more eggs (.366 000/limpet) than those inhabiting quartzite (.119 500/limpet) or mussel shell limpets (.85 800/limpet). Aeolianite limpets also spawned throughout the year, whereas those from the quartzite and mussel shells spawned twice a year (once in winter and once in summer) although a great deal of interannual variability was observed. The onset of sexual maturity occurred at a similar age in all limpets (1 - 2 years) and is probably genetically entrenched. P. granularis inhabiting both an aeolianite and a quartzitic shore were active during nocturnal low tides. All limpets returned to a home scar after foraging. Whilst foraging, limpets inhabiting the aeolianite shore moved shorter distances (.17 cm) at a slower rate than those from quartzite (.30 cm). Limpets that were translocated from one substratum to the other initially moved similar distances to the source group, but after a maximum period of one week, moved distances that mirrored those moved by the resident limpets. Neither season nor tidal phase influenced the distances foraged. No directionality in foraging was found. Wear of radula teeth, particularly the pluricuspid tooth, was greater in limpets from the quartzite. It is hypothesised that the observed differences in life-history parameters and foraging behaviour of limpets both within the south-east coast and between the west and south-east coasts are related to food abundance. Chlorophyll-a, and hence microalgal biomass, was consistently higher on aeolianite (.2.5 times) than on both quartzite and mussel shells. Estimates of chlorophyll-a were higher (although not significantly) in winter. Previous studies determined that primary productivity is also higher along the west coast. Finally, the lack of evidence for migration of limpets from the low-shore to high-shore in south-east coast P. granularis is discussed. It is suggested that this species settles opportunistically within its physiological tolerances and responds morphologically to localised environmental conditions.
- Full Text:
- Date Issued: 2000
- Authors: Vat, Laura Suzanne
- Date: 2000
- Subjects: Patellidae Limpets -- South Africa Mollusks -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5702 , http://hdl.handle.net/10962/d1005388
- Description: Aspects of the biology and ecology of Patella granularis were investigated along a 130km stretch of the south-east coast of South Africa. Distribution, biomass, density and population structure were investigated at seven localities. In addition, a more detailed study of the growth rate and reproductive biology of populations inhabiting three different substrata (aeolianite, quartzitic sandstone and mussel shells) was conducted. The genetic relationships between these three populations was also examined, as was the foraging behaviour of the limpets inhabiting an aeolianite and a quartzitic sandstone shore. Finally, differences in food availability on the different substrata were studied. On the south-east coast, P. granularis has a wide intertidal distribution, occurring from the upper Balanoid zone through to the Cochlear zone, where it is a common inhabitant of mussel shells. The mean shell length of P. granularis was found to decrease down the shore. The largest limpets (46.6 mm shell length) were found on an offshore island in Algoa Bay. At most localities investigated, the sex ratio deviated from a 1:1 ratio with more males than females being recorded on five shores. Both limpet density and biomass were lower on the south-east coast when compared to data published for west coast populations. On the south-east coast, both density and dry biomass were highest in the lower Balanoid zone. Allozyme electrophoresis indicated that P. granularis inhabiting aeolianite, quartzitic sandstone and mussel shells are all part of a single population. Extremely high genetic identity values (0.998), low levels of heterozygosities (0.035 - 0.061), low levels of polymorphisms (25% - 31%) and low FST values (0.021) all suggest that the three populations of P. granularis form a common breeding group, despite the high levels of phenotypic plasticity observed. On all shores, P. granularis was found to grow allometrically, increasing in shell height more rapidly than shell length. Estimation of the growth rate (determined by the Von Bertalanffy growth model) of P. granularis suggested that limpets inhabiting the mussel shells grew more slowly, and attained a smaller maximum size, than those inhabiting both the aeolianite and the quartzite (K = 0.25, 0.32 and 0.33 respectively; 27.12 mm, 31.89 mm and 32.96 mm respectively). Previous work has shown that west coast P. granularis grow more quickly (K = 0.7) and reach a greater size (. 40 mm). Translocation of limpets among sites suggested that limpet size in the mussel beds was spatially constrained. Shell microgrowth bands were deposited tidally, but could not be used for aging limpets due to shell erosion. Limpets from the aeolianite had the greatest reproductive fitness, producing more eggs (.366 000/limpet) than those inhabiting quartzite (.119 500/limpet) or mussel shell limpets (.85 800/limpet). Aeolianite limpets also spawned throughout the year, whereas those from the quartzite and mussel shells spawned twice a year (once in winter and once in summer) although a great deal of interannual variability was observed. The onset of sexual maturity occurred at a similar age in all limpets (1 - 2 years) and is probably genetically entrenched. P. granularis inhabiting both an aeolianite and a quartzitic shore were active during nocturnal low tides. All limpets returned to a home scar after foraging. Whilst foraging, limpets inhabiting the aeolianite shore moved shorter distances (.17 cm) at a slower rate than those from quartzite (.30 cm). Limpets that were translocated from one substratum to the other initially moved similar distances to the source group, but after a maximum period of one week, moved distances that mirrored those moved by the resident limpets. Neither season nor tidal phase influenced the distances foraged. No directionality in foraging was found. Wear of radula teeth, particularly the pluricuspid tooth, was greater in limpets from the quartzite. It is hypothesised that the observed differences in life-history parameters and foraging behaviour of limpets both within the south-east coast and between the west and south-east coasts are related to food abundance. Chlorophyll-a, and hence microalgal biomass, was consistently higher on aeolianite (.2.5 times) than on both quartzite and mussel shells. Estimates of chlorophyll-a were higher (although not significantly) in winter. Previous studies determined that primary productivity is also higher along the west coast. Finally, the lack of evidence for migration of limpets from the low-shore to high-shore in south-east coast P. granularis is discussed. It is suggested that this species settles opportunistically within its physiological tolerances and responds morphologically to localised environmental conditions.
- Full Text:
- Date Issued: 2000
Morphological development in the interlanguage of English learners of Xhosa
- Authors: Hobson, Carol Bonnin
- Date: 2000
- Subjects: Grammar, Comparative and general -- Morphology Xhosa language -- Foreign speakers Xhosa language -- Morphology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2348 , http://hdl.handle.net/10962/d1002630
- Description: This study investigates the development of morphology in the interlanguage of English learners of Xhosa. A quasi-longitudinal research design is used to trace development in the oral interlanguage of six learners of Xhosa for a period of eight months. The elicitation tasks employed range from fairly unstructured conversation tasks to highly structured sentence-manipulation tasks. The learners have varying levels of competence at the beginning of the study and they are exposed to input mainly in formal contexts of learning. One of the aims of the study is to investigate whether the features of interlanguage identified in other studies appear in the learner language in this study. Most other studies discussed in the literature have investigated the features of the interlanguage produced by learners of analytic and inflectional languages. However, this study analyses the interlanguage of learners of an agglutinative language. Studies of other languages have concluded that learners do not use inflectional or agreement morphology at early stages of development and this conclusion is tested for learners of an agglutinative language in this study. Since agreement and inflectional morphology play a central role in conveying meaning in Xhosa, it is found that learners use morphology from the beginning of the learning process. Although forms may be used incorrectly and the functions of forms may be restricted, morphemes appear in the interlanguage of learners of this study earlier than other studies predict. One of the characteristics of early interlanguage and an early form of learner language called the Basic Variety (Klein & Perdue 1997) is the lack of morphology, but this feature proves to be inadequate as a measure of early development in the interlanguage of learners of a language such as Xhosa. This study concludes, therefore, that the presence of morphology in the interlanguage of learners of Xhosa cannot be an indicator of advanced language development.
- Full Text:
- Date Issued: 2000
- Authors: Hobson, Carol Bonnin
- Date: 2000
- Subjects: Grammar, Comparative and general -- Morphology Xhosa language -- Foreign speakers Xhosa language -- Morphology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2348 , http://hdl.handle.net/10962/d1002630
- Description: This study investigates the development of morphology in the interlanguage of English learners of Xhosa. A quasi-longitudinal research design is used to trace development in the oral interlanguage of six learners of Xhosa for a period of eight months. The elicitation tasks employed range from fairly unstructured conversation tasks to highly structured sentence-manipulation tasks. The learners have varying levels of competence at the beginning of the study and they are exposed to input mainly in formal contexts of learning. One of the aims of the study is to investigate whether the features of interlanguage identified in other studies appear in the learner language in this study. Most other studies discussed in the literature have investigated the features of the interlanguage produced by learners of analytic and inflectional languages. However, this study analyses the interlanguage of learners of an agglutinative language. Studies of other languages have concluded that learners do not use inflectional or agreement morphology at early stages of development and this conclusion is tested for learners of an agglutinative language in this study. Since agreement and inflectional morphology play a central role in conveying meaning in Xhosa, it is found that learners use morphology from the beginning of the learning process. Although forms may be used incorrectly and the functions of forms may be restricted, morphemes appear in the interlanguage of learners of this study earlier than other studies predict. One of the characteristics of early interlanguage and an early form of learner language called the Basic Variety (Klein & Perdue 1997) is the lack of morphology, but this feature proves to be inadequate as a measure of early development in the interlanguage of learners of a language such as Xhosa. This study concludes, therefore, that the presence of morphology in the interlanguage of learners of Xhosa cannot be an indicator of advanced language development.
- Full Text:
- Date Issued: 2000
A new role for the non-aligned movement in a post-cold war era
- Authors: Chetty, Mahesh
- Date: 2000
- Subjects: Non-Aligned Movement , Nonalignment , Nonalignment -- Developing countries , International police
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2767 , http://hdl.handle.net/10962/d1002977 , Non-Aligned Movement , Nonalignment , Nonalignment -- Developing countries , International police
- Description: With the disappearance of the superpower conflict that characterised the Cold War era, many observers have begun to question whether the Non-Aligned Movement (NAM) has a role to play in the post Cold War era. However the emergence of a number of issues on the international agenda, such as United Nations peacekeeping operations, global environmental issues and an increasing unwillingness on the part of the major economic powers to abide by GATT/WTO rules, have increasingly become of concern to non-aligned states. However whilst the United States has recognised that these issues require leadership in dealing with them, it has not been willing to supply that leadership. It shall therefore be argued that the changing nature of hegemony in world politics has set conditions that allow non-aligned middle powers and institutions greater scope for action and influence. The emergence of these issues has provided a scope for non-aligned middle powers, acting in accordance with their interests to play alternate leadership roles within an expanded scope for institutions, such as organisations, regimes and multilateralism, in addressing the interests of non-aligned states. Firstly in looking at an expanded role for organisations, the United States has increasingly been unwilling to play a leadership role within UN peacekeeping operations. The continuing importance of the neutrality of UN peacekeeping operations has provided a scope for nonaligned middle powers to play a burden-sharing role with the great powers in addressing the concerns of non-aligned states with regard to these operations. Secondly in looking at an expanded scope for regimes, the emergence of a regime in the issue of ozone depletion may provide a foundation to analyse how non-aligned middle powers may play a bridge-building role between North and South in the issue of climate change. Middle powers could therefore play this role in the absence of United States leadership within this issue. Thirdly, the role of the Cairns Group within the Uruguay Round in addressing non-aligned states’ interests of maintaining stable agricultural trade, can be seen as a model of small group multilateralism in bridging the divide between the major powers in issue specific areas.
- Full Text:
- Date Issued: 2000
- Authors: Chetty, Mahesh
- Date: 2000
- Subjects: Non-Aligned Movement , Nonalignment , Nonalignment -- Developing countries , International police
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2767 , http://hdl.handle.net/10962/d1002977 , Non-Aligned Movement , Nonalignment , Nonalignment -- Developing countries , International police
- Description: With the disappearance of the superpower conflict that characterised the Cold War era, many observers have begun to question whether the Non-Aligned Movement (NAM) has a role to play in the post Cold War era. However the emergence of a number of issues on the international agenda, such as United Nations peacekeeping operations, global environmental issues and an increasing unwillingness on the part of the major economic powers to abide by GATT/WTO rules, have increasingly become of concern to non-aligned states. However whilst the United States has recognised that these issues require leadership in dealing with them, it has not been willing to supply that leadership. It shall therefore be argued that the changing nature of hegemony in world politics has set conditions that allow non-aligned middle powers and institutions greater scope for action and influence. The emergence of these issues has provided a scope for non-aligned middle powers, acting in accordance with their interests to play alternate leadership roles within an expanded scope for institutions, such as organisations, regimes and multilateralism, in addressing the interests of non-aligned states. Firstly in looking at an expanded role for organisations, the United States has increasingly been unwilling to play a leadership role within UN peacekeeping operations. The continuing importance of the neutrality of UN peacekeeping operations has provided a scope for nonaligned middle powers to play a burden-sharing role with the great powers in addressing the concerns of non-aligned states with regard to these operations. Secondly in looking at an expanded scope for regimes, the emergence of a regime in the issue of ozone depletion may provide a foundation to analyse how non-aligned middle powers may play a bridge-building role between North and South in the issue of climate change. Middle powers could therefore play this role in the absence of United States leadership within this issue. Thirdly, the role of the Cairns Group within the Uruguay Round in addressing non-aligned states’ interests of maintaining stable agricultural trade, can be seen as a model of small group multilateralism in bridging the divide between the major powers in issue specific areas.
- Full Text:
- Date Issued: 2000
The economic implications of trade policy reform in South Africa for the automotive industry in the Eastern Cape Province
- Authors: Onyango, Donald Otieno
- Date: 2000
- Subjects: Automobile industry and trade -- South Africa -- Eastern Cape , South Africa -- Commercial policy
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:936 , http://hdl.handle.net/10962/d1002669 , Automobile industry and trade -- South Africa -- Eastern Cape , South Africa -- Commercial policy
- Description: South Africa is no longer a pariah state and has been fully integrated into the global family of nations. With the country’s accession to multilateral agreements like the World Trade Organization (WTO), there has been pressure on the government to abandon its hitherto protectionist trade regime in favour of free and fair trade. Trade liberalisation has had profound implications for the country’s manufacturing sector in general, and the automotive industry in particular, which has seen tariff protection radically slashed and import restrictions greatly eased. Not only has the market share of domestic producers fallen, but increases in exports have to date not matched those of imports. As a result there has been a deterioration in the sector’s balance of trade and a reduction in employment levels, at a time when the country desperately needs to create new jobs. Recent developments, however, suggest that this scenario may be set to change. The thesis applies orthodox neoclassical and heterodox approaches to trade policy to an assessment of the likely economic impact of trade liberalisation on the automotive industry in the Eastern Cape, and by extension nationally. The thesis argues that reliance on orthodox trade theory to inform the direction of trade policy, especially in a developing country context, is unlikely to bring about an adequate increase in the level of exports and employment. This is because liberalisation of the import regime is likely to increase import levels without necessarily stimulating export levels, a scenario which serves to negate the presupposed benefits of liberalisation. The study uses information from surveys conducted on both motor vehicle assemblers and component manufacturing firms to investigate the effect of trade liberalisation on the sector in the Province and finds that, by and large, the motor assemblers have not fared as badly as expected and have in fact positioned themselves to export more vehicles and components. The components sector has had to contend with increased competition from cheaper imports. The thesis, while acknowledging that, as far as possible, free trade is an optimal position, nonetheless argues that governments still have an important role to play in the promotion of industrialisation. The scope of government intervention should, however, be limited to selective interventions which are aimed at counteracting market failure and facilitating innovation and the diffusion of technological know-how. The thesis argues that institution of supply side measures, such as the encouragement of research and development (R&D), skills development and industrial training, is necessary for sustained growth in the manufacturing sector to be realised. The thesis also finds that, contrary to expectations, the liberalisation of the automotive sector has not had the desired effects. Despite an increase in the value of automotive exports and an overall trend towards reduced net foreign exchange usage, employment levels are on the decline. The thesis also finds that without major export initiatives by both motor vehicle assemblers and component manufacturers, the future of the industry will be placed in jeopardy, especially with reduced protection and incentives.
- Full Text:
- Date Issued: 2000
- Authors: Onyango, Donald Otieno
- Date: 2000
- Subjects: Automobile industry and trade -- South Africa -- Eastern Cape , South Africa -- Commercial policy
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:936 , http://hdl.handle.net/10962/d1002669 , Automobile industry and trade -- South Africa -- Eastern Cape , South Africa -- Commercial policy
- Description: South Africa is no longer a pariah state and has been fully integrated into the global family of nations. With the country’s accession to multilateral agreements like the World Trade Organization (WTO), there has been pressure on the government to abandon its hitherto protectionist trade regime in favour of free and fair trade. Trade liberalisation has had profound implications for the country’s manufacturing sector in general, and the automotive industry in particular, which has seen tariff protection radically slashed and import restrictions greatly eased. Not only has the market share of domestic producers fallen, but increases in exports have to date not matched those of imports. As a result there has been a deterioration in the sector’s balance of trade and a reduction in employment levels, at a time when the country desperately needs to create new jobs. Recent developments, however, suggest that this scenario may be set to change. The thesis applies orthodox neoclassical and heterodox approaches to trade policy to an assessment of the likely economic impact of trade liberalisation on the automotive industry in the Eastern Cape, and by extension nationally. The thesis argues that reliance on orthodox trade theory to inform the direction of trade policy, especially in a developing country context, is unlikely to bring about an adequate increase in the level of exports and employment. This is because liberalisation of the import regime is likely to increase import levels without necessarily stimulating export levels, a scenario which serves to negate the presupposed benefits of liberalisation. The study uses information from surveys conducted on both motor vehicle assemblers and component manufacturing firms to investigate the effect of trade liberalisation on the sector in the Province and finds that, by and large, the motor assemblers have not fared as badly as expected and have in fact positioned themselves to export more vehicles and components. The components sector has had to contend with increased competition from cheaper imports. The thesis, while acknowledging that, as far as possible, free trade is an optimal position, nonetheless argues that governments still have an important role to play in the promotion of industrialisation. The scope of government intervention should, however, be limited to selective interventions which are aimed at counteracting market failure and facilitating innovation and the diffusion of technological know-how. The thesis argues that institution of supply side measures, such as the encouragement of research and development (R&D), skills development and industrial training, is necessary for sustained growth in the manufacturing sector to be realised. The thesis also finds that, contrary to expectations, the liberalisation of the automotive sector has not had the desired effects. Despite an increase in the value of automotive exports and an overall trend towards reduced net foreign exchange usage, employment levels are on the decline. The thesis also finds that without major export initiatives by both motor vehicle assemblers and component manufacturers, the future of the industry will be placed in jeopardy, especially with reduced protection and incentives.
- Full Text:
- Date Issued: 2000
Electrocatalytic properties of vitamin B12 towards oxidation and reduction of nitric oxide
- Vilakazi, Sibulelo Lea, Nyokong, Tebello
- Authors: Vilakazi, Sibulelo Lea , Nyokong, Tebello
- Date: 2000
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/293196 , vital:57064 , xlink:href="https://doi.org/10.1016/S0013-4686(00)00628-9"
- Description: This paper reports on the catalytic behaviour of cyanocobalamin (VB12) towards the reduction and oxidation of nitric oxide. When VB12 is adsorbed on glassy carbon electrodes, it catalyses the reduction of nitric oxide (NO) in pH 4 and 9 buffers. In the absence of NO, cyclic voltammetry shows that VB12 is reduced by a one-step two-electron reduction from CoIII to the CoI species. Addition of NO at pH 9 to solutions of VB12 resulted in the splitting of the cyclic voltammetry peaks as a result of a consecutive one-electron reduction of the central CoIII metal in VB12 to CoII and finally to CoI. The catalytic peak for oxidation of NO on a glassy carbon electrode modified with VB12 was observed at 1.21 V versus Ag∣AgCl, at pH 9. The products of the catalytic reduction of nitric oxide include ammonia and hydroxylamine.
- Full Text:
- Date Issued: 2000
- Authors: Vilakazi, Sibulelo Lea , Nyokong, Tebello
- Date: 2000
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/293196 , vital:57064 , xlink:href="https://doi.org/10.1016/S0013-4686(00)00628-9"
- Description: This paper reports on the catalytic behaviour of cyanocobalamin (VB12) towards the reduction and oxidation of nitric oxide. When VB12 is adsorbed on glassy carbon electrodes, it catalyses the reduction of nitric oxide (NO) in pH 4 and 9 buffers. In the absence of NO, cyclic voltammetry shows that VB12 is reduced by a one-step two-electron reduction from CoIII to the CoI species. Addition of NO at pH 9 to solutions of VB12 resulted in the splitting of the cyclic voltammetry peaks as a result of a consecutive one-electron reduction of the central CoIII metal in VB12 to CoII and finally to CoI. The catalytic peak for oxidation of NO on a glassy carbon electrode modified with VB12 was observed at 1.21 V versus Ag∣AgCl, at pH 9. The products of the catalytic reduction of nitric oxide include ammonia and hydroxylamine.
- Full Text:
- Date Issued: 2000
The representation of "South Africanness" in the locally produced television production, Generations
- Authors: Dentlinger, Lindsay
- Date: 2000
- Subjects: Television soap operas -- South Africa , National characteristics, South African, In Literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3425 , http://hdl.handle.net/10962/d1002878 , Television soap operas -- South Africa , National characteristics, South African, In Literature
- Description: The aim of this study is to analyse selected episodes of the locally produced television programme Generations, in order to identify specific ways in which the programme seeks to forge a South African identity, and in so doing, 'flag' our nationhood as South Africans. These elements of 'South Africanness' are broadly defined as connections to a South African way of life, context, values and experiences. Generations is a programme produced under South African broadcasting local content provisions. These provisions arise out of the need, inter alia, to reflect the identity and multi-cultural nature of South Africa in order to foster 'national identity' and 'national culture'. These elements of 'South Africanness' are extracted through a genre and ideological analysis of selected sample episodes, taking into consideration the theoretical frameworks of the politics of representation and identity. The production context of, and representations made, in Generations, are found to be situated largely within the context of the South African discourses of the ‘rainbow nation', 'African renaissance' and 'black economic empowerment'. The analysis concludes that through the various categories of representations of 'South Africanness' in the selected episodes of Generations, specific instances of identity, that of national culture and national identity are formed.
- Full Text:
- Date Issued: 2000
The representation of "South Africanness" in the locally produced television production, Generations
- Authors: Dentlinger, Lindsay
- Date: 2000
- Subjects: Television soap operas -- South Africa , National characteristics, South African, In Literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3425 , http://hdl.handle.net/10962/d1002878 , Television soap operas -- South Africa , National characteristics, South African, In Literature
- Description: The aim of this study is to analyse selected episodes of the locally produced television programme Generations, in order to identify specific ways in which the programme seeks to forge a South African identity, and in so doing, 'flag' our nationhood as South Africans. These elements of 'South Africanness' are broadly defined as connections to a South African way of life, context, values and experiences. Generations is a programme produced under South African broadcasting local content provisions. These provisions arise out of the need, inter alia, to reflect the identity and multi-cultural nature of South Africa in order to foster 'national identity' and 'national culture'. These elements of 'South Africanness' are extracted through a genre and ideological analysis of selected sample episodes, taking into consideration the theoretical frameworks of the politics of representation and identity. The production context of, and representations made, in Generations, are found to be situated largely within the context of the South African discourses of the ‘rainbow nation', 'African renaissance' and 'black economic empowerment'. The analysis concludes that through the various categories of representations of 'South Africanness' in the selected episodes of Generations, specific instances of identity, that of national culture and national identity are formed.
- Full Text:
- Date Issued: 2000
Workers are parents too
- SACCAWU
- Authors: SACCAWU
- Date: 2000
- Subjects: SACCAWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/113858 , vital:33838
- Description: This booklet is a follow-up to the Parental Rights' Manual for negotiators produced by SACCAWU in 1999. These publications have been the product of painful soul- searching. They are attempts to highlight the plight of women in the workplace and represent the uncompromising resolve of the union to challenge the inequalities and discrimination that workers, especially women, suffer as parents. This booklet is intended to assist negotiators, shop stewards and ordinary workers in knowing and exercising their parental rights. In order to win the struggle for parental rights, the understanding of worker rights must reach all the way to the shop floor. This booklet will help to make that understanding a reality. We wish to thank the commitment and dedication by all workers and union officials who have worked tirelessly for the realisation of the noble goal of parental rights and have forced the bosses to reason beyond dogmatic greed to maximise profits. Achievements won thus far have not been easy victories, nor can they be attributed to kindness or a change of heart by the employers. This booklet builds on our manual and further inspires us to translate our dreams into reality.
- Full Text:
- Date Issued: 2000
- Authors: SACCAWU
- Date: 2000
- Subjects: SACCAWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/113858 , vital:33838
- Description: This booklet is a follow-up to the Parental Rights' Manual for negotiators produced by SACCAWU in 1999. These publications have been the product of painful soul- searching. They are attempts to highlight the plight of women in the workplace and represent the uncompromising resolve of the union to challenge the inequalities and discrimination that workers, especially women, suffer as parents. This booklet is intended to assist negotiators, shop stewards and ordinary workers in knowing and exercising their parental rights. In order to win the struggle for parental rights, the understanding of worker rights must reach all the way to the shop floor. This booklet will help to make that understanding a reality. We wish to thank the commitment and dedication by all workers and union officials who have worked tirelessly for the realisation of the noble goal of parental rights and have forced the bosses to reason beyond dogmatic greed to maximise profits. Achievements won thus far have not been easy victories, nor can they be attributed to kindness or a change of heart by the employers. This booklet builds on our manual and further inspires us to translate our dreams into reality.
- Full Text:
- Date Issued: 2000
Genetic variation within and between some rare and common taxa of Cape Proteaceae and the implications for their conservation
- Authors: Brown, Susan Ann
- Date: 2000
- Subjects: Proteaceae -- South Africa Nature conservation -- South Africa Plant conservation -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3905 , http://hdl.handle.net/10962/d1003964
- Full Text:
- Date Issued: 2000
- Authors: Brown, Susan Ann
- Date: 2000
- Subjects: Proteaceae -- South Africa Nature conservation -- South Africa Plant conservation -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3905 , http://hdl.handle.net/10962/d1003964
- Full Text:
- Date Issued: 2000
Latent murderousness: an exploration of the nature and quality of object relations in rage-type murderers
- Authors: Cartwright, Duncan James
- Date: 2000
- Subjects: Murder Murder -- Case studies Murderers -- Psychology Criminal psychology Violence Narcissism Aggressiveness Anger
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2946 , http://hdl.handle.net/10962/d1002455
- Description: In this dissertation I investigate the intrapsychic make-up of rage-type offenders and explore the psychodynamics of the act of murder itself The dissertation begins with a discussion on the defining features of the act of rage-type murder. I then consider the role of personality characteristics and psychopathology in individuals who have committed such offences. With the basic features of the offender and act itself outlined, the following section reviews key areas of debate regarding the psychodynamics of violence and the intrapsychic make-up of the rage-type murderer. I first explore the nature of aggression as debated in psychoanalysis and conclude that the views expressed are often unn,ecessarily polarized regarding the origins of aggression and suggest that the specifics of particular types of aggression require consideration in order to assess their intrapsychic nature. The specifics of rage and violence are discussed with this in mind. In the second chapter of this section I develop a number of intrapsychic dimensions to be used in understanding how different types of violence are constituted. Psychodynamic contributions towards understanding rage-type murder, as a specific form of violence, are then discussed. Following this review, a number of directive ~uestions are formulated regarding (1) the intrapsychic dimension of rage-type murder; (2) the pJ;esence of the borderline personality in such offender~ and its intrapsychic nature; and (3) the_ specific psychodynamics that lie behind what is argued to be a defensive act of murder. A multiple case study approach, using nine imprisoned rage-type offenders, is used to further explore the above issues. Court summary reports, the Thematic Apperception Test and the Psychoanalytic Research Interview comprised the research material, with particular emphasis placed on the interview material. The interview is approached from a psychoanalytic perspective and I develop some theoretical, technical and analytical guidelines to try to broaden Jhe use of psychoanalysis in the research domain. Findings of the research reveal a specific kind of defensive organization that is characterized by a constellation of object relations that I term the 'narcissistic exoskeleton'. I suggest that these findings best fit the description of a particular kind of borderline personality organization typified by apparent 'normality'. Other prominent aspects of the dimensions of violence observed in these cases include: (1) a poor representational capacity; (2) an interactional style characterized by uncontainable projective exchanges between victim and offender; (3) a collusive primary object relationship combined with the absence of an internalized 'third object'; (4) a 'two-faced' superego structure; (5) the internalization of traumatic experience that has become associated with a bad object system; (6) phantasies of restoring ideal good in external objects alongside conscious fantasies of annihilation. Within the context of these factors the intrapsychic events that lead to the act itself are discussed. It is found that a collapse of the 'narcissistic exoskeleton', the intrusion of the bad object system and the unbearable shame that this evokes in the offender are prominent features of what culminates in an act of explosive rage and projective identification. Some of the implications of my research are briefly discussed in the concluding chapter.
- Full Text:
- Date Issued: 2000
- Authors: Cartwright, Duncan James
- Date: 2000
- Subjects: Murder Murder -- Case studies Murderers -- Psychology Criminal psychology Violence Narcissism Aggressiveness Anger
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2946 , http://hdl.handle.net/10962/d1002455
- Description: In this dissertation I investigate the intrapsychic make-up of rage-type offenders and explore the psychodynamics of the act of murder itself The dissertation begins with a discussion on the defining features of the act of rage-type murder. I then consider the role of personality characteristics and psychopathology in individuals who have committed such offences. With the basic features of the offender and act itself outlined, the following section reviews key areas of debate regarding the psychodynamics of violence and the intrapsychic make-up of the rage-type murderer. I first explore the nature of aggression as debated in psychoanalysis and conclude that the views expressed are often unn,ecessarily polarized regarding the origins of aggression and suggest that the specifics of particular types of aggression require consideration in order to assess their intrapsychic nature. The specifics of rage and violence are discussed with this in mind. In the second chapter of this section I develop a number of intrapsychic dimensions to be used in understanding how different types of violence are constituted. Psychodynamic contributions towards understanding rage-type murder, as a specific form of violence, are then discussed. Following this review, a number of directive ~uestions are formulated regarding (1) the intrapsychic dimension of rage-type murder; (2) the pJ;esence of the borderline personality in such offender~ and its intrapsychic nature; and (3) the_ specific psychodynamics that lie behind what is argued to be a defensive act of murder. A multiple case study approach, using nine imprisoned rage-type offenders, is used to further explore the above issues. Court summary reports, the Thematic Apperception Test and the Psychoanalytic Research Interview comprised the research material, with particular emphasis placed on the interview material. The interview is approached from a psychoanalytic perspective and I develop some theoretical, technical and analytical guidelines to try to broaden Jhe use of psychoanalysis in the research domain. Findings of the research reveal a specific kind of defensive organization that is characterized by a constellation of object relations that I term the 'narcissistic exoskeleton'. I suggest that these findings best fit the description of a particular kind of borderline personality organization typified by apparent 'normality'. Other prominent aspects of the dimensions of violence observed in these cases include: (1) a poor representational capacity; (2) an interactional style characterized by uncontainable projective exchanges between victim and offender; (3) a collusive primary object relationship combined with the absence of an internalized 'third object'; (4) a 'two-faced' superego structure; (5) the internalization of traumatic experience that has become associated with a bad object system; (6) phantasies of restoring ideal good in external objects alongside conscious fantasies of annihilation. Within the context of these factors the intrapsychic events that lead to the act itself are discussed. It is found that a collapse of the 'narcissistic exoskeleton', the intrusion of the bad object system and the unbearable shame that this evokes in the offender are prominent features of what culminates in an act of explosive rage and projective identification. Some of the implications of my research are briefly discussed in the concluding chapter.
- Full Text:
- Date Issued: 2000
The analysis of trace gas emissions from landfills
- Authors: Rubidge, Gletwyn Robert
- Date: 2000
- Subjects: Gases, Asphyxiating and poisonnous , Gases -- Analysis , Sanitation -- Environmental engineering
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10983 , http://hdl.handle.net/10948/d1006341 , Gases, Asphyxiating and poisonnous , Gases -- Analysis , Sanitation -- Environmental engineering
- Description: Numerous informal houses have been built on and adjacent to a landfill in iBayi, Port Elizabeth, South Africa, which accepted domestic and industrial waste. Formal housing surrounds most of the site at a greater distance - some 60 m, or further, from the landfill. Both formal and informally housed residents complain of odours, burning eyes, sore throats and headaches - symptoms which they believed were caused by the landfill. The landfill gas and ambient air were analyzed to classify and quantify the VOCs (volatile organic compounds) emitted and then to compare the quantitative data with recognised standards to establish if the residents are at risk. Eighteen target (potentially hazardous) VOCs were quantified. A wide variety of compounds were detected in both the ambient air and landfill gas. The results of the VOC analyses were similar to those of other workers in both the qualitative and quantitative studies. The concentrations of the VOCs were mostly lower than the TLV (threshold limit values) values, but exceeded the MRLs (minimum recommended levels). The combined concentrations of the VOC’s in the ambient air either approached or exceeded the limit values for combined exposure thus indicating that a potential health hazard exists. One third of the VOCs were detected in both the ambient air and the subsurface gas, however, external pollution sources also appear to contribute to the VOC concentrations ambient air. Dangerously high methane concentrations were repeatedly detected in the landfill gas amongst the informal houses. There was a vast improvement in the aesthetic qualities of the landfill since the disposal restriction to accept only domestic refuse and building rubble in July 1997. The ambient air was less odorous and landfill site littered. Fewer informal recyclers were present and their concomitant squabbling over valuables had almost vanished. The management of the iBayi landfill holds much room for improvement. There is potential for serious injury or even death if no action is taken to remedy the problems at the iBayi landfill. A holistic solution will have to be found to make the landfill a safe neighbour. Some complementary analyses (such as pH, heavy metal concentrations in the water and sediments etc.) were performed on the leachate and water surrounding the landfill.
- Full Text:
- Date Issued: 2000
- Authors: Rubidge, Gletwyn Robert
- Date: 2000
- Subjects: Gases, Asphyxiating and poisonnous , Gases -- Analysis , Sanitation -- Environmental engineering
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10983 , http://hdl.handle.net/10948/d1006341 , Gases, Asphyxiating and poisonnous , Gases -- Analysis , Sanitation -- Environmental engineering
- Description: Numerous informal houses have been built on and adjacent to a landfill in iBayi, Port Elizabeth, South Africa, which accepted domestic and industrial waste. Formal housing surrounds most of the site at a greater distance - some 60 m, or further, from the landfill. Both formal and informally housed residents complain of odours, burning eyes, sore throats and headaches - symptoms which they believed were caused by the landfill. The landfill gas and ambient air were analyzed to classify and quantify the VOCs (volatile organic compounds) emitted and then to compare the quantitative data with recognised standards to establish if the residents are at risk. Eighteen target (potentially hazardous) VOCs were quantified. A wide variety of compounds were detected in both the ambient air and landfill gas. The results of the VOC analyses were similar to those of other workers in both the qualitative and quantitative studies. The concentrations of the VOCs were mostly lower than the TLV (threshold limit values) values, but exceeded the MRLs (minimum recommended levels). The combined concentrations of the VOC’s in the ambient air either approached or exceeded the limit values for combined exposure thus indicating that a potential health hazard exists. One third of the VOCs were detected in both the ambient air and the subsurface gas, however, external pollution sources also appear to contribute to the VOC concentrations ambient air. Dangerously high methane concentrations were repeatedly detected in the landfill gas amongst the informal houses. There was a vast improvement in the aesthetic qualities of the landfill since the disposal restriction to accept only domestic refuse and building rubble in July 1997. The ambient air was less odorous and landfill site littered. Fewer informal recyclers were present and their concomitant squabbling over valuables had almost vanished. The management of the iBayi landfill holds much room for improvement. There is potential for serious injury or even death if no action is taken to remedy the problems at the iBayi landfill. A holistic solution will have to be found to make the landfill a safe neighbour. Some complementary analyses (such as pH, heavy metal concentrations in the water and sediments etc.) were performed on the leachate and water surrounding the landfill.
- Full Text:
- Date Issued: 2000
South Africa's growth, employment and redistribution strategy in the context of structural adjustment programmes in the South
- Authors: Lehloesa, Thembinkosi L
- Date: 2000
- Subjects: Growth, Employment And Redistribution Programme (South Africa) , South Africa -- Economic policy , South Africa -- Politics and government -- 1989-1994
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2794 , http://hdl.handle.net/10962/d1003004 , Growth, Employment And Redistribution Programme (South Africa) , South Africa -- Economic policy , South Africa -- Politics and government -- 1989-1994
- Description: This study is a contribution to the ongoing debate concerning the future of South Africa’s macro-economic policy known as the Growth, Employment and Redistribution (GEAR) strategy. The study attempts to draw parallels between the GEAR macro-economic policy framework and structural adjustment programmes in the South. By making use of this comparison, the study argues that the outcome of the GEAR will be no different from structural adjustment programmes in that it will fail to reduce poverty and cause government to meet the basic needs of the people. These conclusions are drawn from the fact that the GEAR policy is premised on the faith that the market is capable of redistributing income and wealth, and providing people with their basic needs.
- Full Text:
- Date Issued: 2000
- Authors: Lehloesa, Thembinkosi L
- Date: 2000
- Subjects: Growth, Employment And Redistribution Programme (South Africa) , South Africa -- Economic policy , South Africa -- Politics and government -- 1989-1994
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2794 , http://hdl.handle.net/10962/d1003004 , Growth, Employment And Redistribution Programme (South Africa) , South Africa -- Economic policy , South Africa -- Politics and government -- 1989-1994
- Description: This study is a contribution to the ongoing debate concerning the future of South Africa’s macro-economic policy known as the Growth, Employment and Redistribution (GEAR) strategy. The study attempts to draw parallels between the GEAR macro-economic policy framework and structural adjustment programmes in the South. By making use of this comparison, the study argues that the outcome of the GEAR will be no different from structural adjustment programmes in that it will fail to reduce poverty and cause government to meet the basic needs of the people. These conclusions are drawn from the fact that the GEAR policy is premised on the faith that the market is capable of redistributing income and wealth, and providing people with their basic needs.
- Full Text:
- Date Issued: 2000
The interpretation of ABET placement tests in the recognition of prior learning
- Authors: Blunt, Sandra Viki
- Date: 2000
- Subjects: English language -- Ability testing , English language -- Study and teaching -- Foreign speakers
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:1582 , http://hdl.handle.net/10962/d1003464
- Description: This thesis analyses the way in which placement testing is being interpreted in Adult Basic Education and Training (ABET). The thesis examines whether the placement tests used in the case study were valid in terms of whether their contents were relevant and authentic with regard to what English second language speakers could reasonably be expected to know. Adult learners have differing English second language knowledge depending on the different contexts in which they have learned their second language. This thesis investigates the implications of the different contexts and different language needs of adult learners for the testing of English as a second language for placement purposes in ABET programmes. The thesis examined two placement tests to determine how the recognition of prior second language learning was being interpreted and how the interpretation affected the validity of the tests. Learners= perceptions of the assessment process and test content were elicited in order to determine whether a policy of transparency had been followed in the implementation of the assessment. It was also established what the goals of the organisation were in implementing an ABET programme. This research suggests that placement testing should be viewed holistically; in other words, the goals of the organisation and the level of transparency affect the validity of the placement test. The conclusions were that the placement tests were inauthentic since their contents excluded certain vital aspects of real life performance, namely, that related to the work context. The research revealed that if the placement testing process and the ABET programme are integrated into the culture of the organisation and if employees are remunerated when they have passed the different levels in the programme, the programme is likely to achieve a fair measure of success. Recommendations are that literacy should be viewed as based on a variety of contexts and uses and that therefore tests should be tailored to suit each particular organisation and should contain workrelated content. Furthermore, multiple methods of assessment should be considered.
- Full Text:
- Date Issued: 2000
- Authors: Blunt, Sandra Viki
- Date: 2000
- Subjects: English language -- Ability testing , English language -- Study and teaching -- Foreign speakers
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:1582 , http://hdl.handle.net/10962/d1003464
- Description: This thesis analyses the way in which placement testing is being interpreted in Adult Basic Education and Training (ABET). The thesis examines whether the placement tests used in the case study were valid in terms of whether their contents were relevant and authentic with regard to what English second language speakers could reasonably be expected to know. Adult learners have differing English second language knowledge depending on the different contexts in which they have learned their second language. This thesis investigates the implications of the different contexts and different language needs of adult learners for the testing of English as a second language for placement purposes in ABET programmes. The thesis examined two placement tests to determine how the recognition of prior second language learning was being interpreted and how the interpretation affected the validity of the tests. Learners= perceptions of the assessment process and test content were elicited in order to determine whether a policy of transparency had been followed in the implementation of the assessment. It was also established what the goals of the organisation were in implementing an ABET programme. This research suggests that placement testing should be viewed holistically; in other words, the goals of the organisation and the level of transparency affect the validity of the placement test. The conclusions were that the placement tests were inauthentic since their contents excluded certain vital aspects of real life performance, namely, that related to the work context. The research revealed that if the placement testing process and the ABET programme are integrated into the culture of the organisation and if employees are remunerated when they have passed the different levels in the programme, the programme is likely to achieve a fair measure of success. Recommendations are that literacy should be viewed as based on a variety of contexts and uses and that therefore tests should be tailored to suit each particular organisation and should contain workrelated content. Furthermore, multiple methods of assessment should be considered.
- Full Text:
- Date Issued: 2000
Desert
- Authors: Harper, Sean Julian
- Date: 2000
- Subjects: Rawls, John, 1921-2002 , Rawls, John, 1921-2002 Theory of justice , Ethics
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2710 , http://hdl.handle.net/10962/d1002840 , Rawls, John, 1921-2002 , Rawls, John, 1921-2002 Theory of justice , Ethics
- Description: This thesis examines the idea of desert as expounded in the work of John Rawls, and some of the implications of this conception of desert for moral and political philosophy. In this work, I analyse a series of arguments against retaining this particular conception of desert.I argue that none of these arguments sufficiently diminishes the force of Rawls’ argument for desert, while many of them do state, and I argue that they are correct in doing so, that this conception of desert is dangerous for political or moral philosophy to maintain. I argue that the moral, political and legal implications of accepting this account of desert severely undermine various institutions of differential treatment, and indeed, moral assessment. I regard it as obvious that societies must, on occasion, treat members of those societies differently, for moral, as well as practical reasons. The Rawlsian account of desert, and the account of responsibility on which it rests, however, will endanger the legitimacy of such procedures. I argue further that the Rawlsian account of desert requires that differences in wealth, and inheritance of wealth, influence and privilege be diminished, if not abolished, if we are to talk of any form of desert meaningfully. I argue that this is a strength of Rawls’ account, and further that any account of desert that is true to the philosophical tradition of the concept will require similar steps to be taken. The primary aim of this thesis is to show that Rawls’ arguments against desert are serious ones, both in terms of strength and scope, and that they must be addressed. I intend to show that these arguments are founded on strong moral intuitions, and that it is plausible that these intuitions may need revision. Finally,I intend to show that desert is an important moral and political concept, and that the disciplines of moral and political philosophy will be impoverished by the absence this concept. This absence, I will argue, is a natural consequence of the acceptance of the Rawlsian arguments.
- Full Text:
- Date Issued: 2000
- Authors: Harper, Sean Julian
- Date: 2000
- Subjects: Rawls, John, 1921-2002 , Rawls, John, 1921-2002 Theory of justice , Ethics
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2710 , http://hdl.handle.net/10962/d1002840 , Rawls, John, 1921-2002 , Rawls, John, 1921-2002 Theory of justice , Ethics
- Description: This thesis examines the idea of desert as expounded in the work of John Rawls, and some of the implications of this conception of desert for moral and political philosophy. In this work, I analyse a series of arguments against retaining this particular conception of desert.I argue that none of these arguments sufficiently diminishes the force of Rawls’ argument for desert, while many of them do state, and I argue that they are correct in doing so, that this conception of desert is dangerous for political or moral philosophy to maintain. I argue that the moral, political and legal implications of accepting this account of desert severely undermine various institutions of differential treatment, and indeed, moral assessment. I regard it as obvious that societies must, on occasion, treat members of those societies differently, for moral, as well as practical reasons. The Rawlsian account of desert, and the account of responsibility on which it rests, however, will endanger the legitimacy of such procedures. I argue further that the Rawlsian account of desert requires that differences in wealth, and inheritance of wealth, influence and privilege be diminished, if not abolished, if we are to talk of any form of desert meaningfully. I argue that this is a strength of Rawls’ account, and further that any account of desert that is true to the philosophical tradition of the concept will require similar steps to be taken. The primary aim of this thesis is to show that Rawls’ arguments against desert are serious ones, both in terms of strength and scope, and that they must be addressed. I intend to show that these arguments are founded on strong moral intuitions, and that it is plausible that these intuitions may need revision. Finally,I intend to show that desert is an important moral and political concept, and that the disciplines of moral and political philosophy will be impoverished by the absence this concept. This absence, I will argue, is a natural consequence of the acceptance of the Rawlsian arguments.
- Full Text:
- Date Issued: 2000
Designing and implementing a virtual reality interaction framework
- Authors: Rorke, Michael
- Date: 2000
- Subjects: Virtual reality , Computer simulation , Human-computer interaction , Computer graphics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4623 , http://hdl.handle.net/10962/d1006491 , Virtual reality , Computer simulation , Human-computer interaction , Computer graphics
- Description: Virtual Reality offers the possibility for humans to interact in a more natural way with the computer and its applications. Currently, Virtual Reality is used mainly in the field of visualisation where 3D graphics allow users to more easily view complex sets of data or structures. The field of interaction in Virtual Reality has been largely neglected due mainly to problems with input devices and equipment costs. Recent research has aimed to overcome these interaction problems, thereby creating a usable interaction platform for Virtual Reality. This thesis presents a background into the field of interaction in Virtual Reality. It goes on to propose a generic framework for the implementation of common interaction techniques into a homogeneous application development environment. This framework adds a new layer to the standard Virtual Reality toolkit – the interaction abstraction layer, or interactor layer. This separation is in line with current HCI practices. The interactor layer is further divided into specific sections – input component, interaction component, system component, intermediaries, entities and widgets. Each of these performs a specific function, with clearly defined interfaces between the different components to promote easy objectoriented implementation of the framework. The validity of the framework is shown in comparison with accepted taxonomies in the area of Virtual Reality interaction. Thus demonstrating that the framework covers all the relevant factors involved in the field. Furthermore, the thesis describes an implementation of this framework. The implementation was completed using the Rhodes University CoRgi Virtual Reality toolkit. Several postgraduate students in the Rhodes University Computer Science Department utilised the framework implementation to develop a set of case studies. These case studies demonstrate the practical use of the framework to create useful Virtual Reality applications, as well as demonstrating the generic nature of the framework and its extensibility to be able to handle new interaction techniques. Finally, the generic nature of the framework is further demonstrated by moving it from the standard CoRgi Virtual Reality toolkit, to a distributed version of this toolkit. The distributed implementation of the framework utilises the Common Object Request Broker Architecture (CORBA) to implement the distribution of the objects in the system. Using this distributed implementation, we are able to ascertain that CORBA is useful in the field of distributed real-time Virtual Reality, even taking into account the extra overhead introduced by the additional abstraction layer. We conclude from this thesis that it is important to abstract the interaction layer from the other layers of a Virtual Reality toolkit in order to provide a consistent interface to developers. We have shown that our framework is implementable and useful in the field, making it easier for developers to include interaction in their Virtual Reality applications. Our framework is able to handle all the current aspects of interaction in Virtual Reality, as well as being general enough to implement future interaction techniques. The framework is also applicable to different Virtual Reality toolkits and development platforms, making it ideal for developing general, cross-platform interactive Virtual Reality applications.
- Full Text:
- Date Issued: 2000
- Authors: Rorke, Michael
- Date: 2000
- Subjects: Virtual reality , Computer simulation , Human-computer interaction , Computer graphics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4623 , http://hdl.handle.net/10962/d1006491 , Virtual reality , Computer simulation , Human-computer interaction , Computer graphics
- Description: Virtual Reality offers the possibility for humans to interact in a more natural way with the computer and its applications. Currently, Virtual Reality is used mainly in the field of visualisation where 3D graphics allow users to more easily view complex sets of data or structures. The field of interaction in Virtual Reality has been largely neglected due mainly to problems with input devices and equipment costs. Recent research has aimed to overcome these interaction problems, thereby creating a usable interaction platform for Virtual Reality. This thesis presents a background into the field of interaction in Virtual Reality. It goes on to propose a generic framework for the implementation of common interaction techniques into a homogeneous application development environment. This framework adds a new layer to the standard Virtual Reality toolkit – the interaction abstraction layer, or interactor layer. This separation is in line with current HCI practices. The interactor layer is further divided into specific sections – input component, interaction component, system component, intermediaries, entities and widgets. Each of these performs a specific function, with clearly defined interfaces between the different components to promote easy objectoriented implementation of the framework. The validity of the framework is shown in comparison with accepted taxonomies in the area of Virtual Reality interaction. Thus demonstrating that the framework covers all the relevant factors involved in the field. Furthermore, the thesis describes an implementation of this framework. The implementation was completed using the Rhodes University CoRgi Virtual Reality toolkit. Several postgraduate students in the Rhodes University Computer Science Department utilised the framework implementation to develop a set of case studies. These case studies demonstrate the practical use of the framework to create useful Virtual Reality applications, as well as demonstrating the generic nature of the framework and its extensibility to be able to handle new interaction techniques. Finally, the generic nature of the framework is further demonstrated by moving it from the standard CoRgi Virtual Reality toolkit, to a distributed version of this toolkit. The distributed implementation of the framework utilises the Common Object Request Broker Architecture (CORBA) to implement the distribution of the objects in the system. Using this distributed implementation, we are able to ascertain that CORBA is useful in the field of distributed real-time Virtual Reality, even taking into account the extra overhead introduced by the additional abstraction layer. We conclude from this thesis that it is important to abstract the interaction layer from the other layers of a Virtual Reality toolkit in order to provide a consistent interface to developers. We have shown that our framework is implementable and useful in the field, making it easier for developers to include interaction in their Virtual Reality applications. Our framework is able to handle all the current aspects of interaction in Virtual Reality, as well as being general enough to implement future interaction techniques. The framework is also applicable to different Virtual Reality toolkits and development platforms, making it ideal for developing general, cross-platform interactive Virtual Reality applications.
- Full Text:
- Date Issued: 2000
Strike comparison of the compositional variations of the lower group and middle group chromitite seams of the critical zone, Western Bushveld complex
- Authors: Doig, Heather Leslie
- Date: 2000
- Subjects: Chromite -- South Africa , Geology -- South Africa , Mineralogy -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5005 , http://hdl.handle.net/10962/d1005618
- Description: The variations in the composition, specifically the Cr20 S content and the Cr:Fe ratio, and the morphology of the Lower Group (LG) and Middle Group (MG) chromitite seams of the Critical Zone (CZ) across the western Bushveld Complex, including the Ruighoek and Brits sections, is investigated by means of whole-rock chemical data, both major and trace elements analysis, XRD and electron microprobe data. As a result ofthe paucity of exposed or developed LG1 - LG5 chromitite seams in the western Bushveld Complex, this study is confined to the investigation of the compositional variations of the LG6 to MG4 chromitite seams. In only one section, the Ruighoek section, was the entire succession of chromitite seams, from the LG1 - MG4, exposed. The silicate host rocks from the LG6 pyroxenite footwall to the collar of the CC2 drillcore (lower uCZ) in the Rustenburg section were sampled. This study reviews the compositional trends of the silicate host rocks, as the compositional variations of the chromitite seams reflect the chemical evolution of the host cumulate environment and, to a lesser degree, the composition onhe interstitial mineral phases in the chromitite seams. The compositional variations of the LG and MG chromitite seams are attributed to the compositional contrast between the replenishing magma and the resident magma. The chemical trends of the LG and MG chromitite layers and the host cumUlate rOCKS do not support the existence of two compositionalfy dissimilar magmas in the CZ, rather the cyclic layering of the CZ and the chemical variations of the chromitite seams are attributed to the mixing of primitive magma with the resident magma, both of which have essentially similar compositions. The compositional variations of the LG and MG chromitite seams along strike away from the supposed feeder site (Union section) to the distal facies (Brits section) are attributed to the advanced compositional contrast between the resident magma and the replenishing primitive magma pulses. The CZ is characterized by reversals in fractionation trends and this is attributed to the compositional evolution of the parental magma and not to the replenishment of the resident magma by influxes of grossly dissimilar magma compositions. The Cr20 S content and the Cr:Fe ratio of the MG chromitite layers increase from the Ruighoek (near proximal) section to the Brits section (distal facies). This is attributed to the advanced compositional contrasts between the resident magma and the replenishing primitive magma. In contrast, the Cr20 3 content and Cr:Fe ratios ofthe LG6 and LG8a chromitite seams decreases eastwards from the Ruighoek section. The average Cr:Fe ratio for the western Bushveld Complex is between 1.5 and\2.0, nonetheless, a progressively lower Cr:Fe ratio is noted from the LG1 chromitite up through to the MG4 chromitite seam in the Ruighoek section. tn the LG2 - LG4 chromitite interval a deviation to higher.lratios is encountered. A progressive substitution of Cr by AT and Fe in the Cr-spinel crystal lattice characterizes the chromitite succession from the LG1 seam up through the chromitite succession to MG4. The petrogeneSiS of the chromitite seams of the CZ is attributed to magma mixing and fractional crystallization of a single magma type.
- Full Text:
- Date Issued: 2000
- Authors: Doig, Heather Leslie
- Date: 2000
- Subjects: Chromite -- South Africa , Geology -- South Africa , Mineralogy -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5005 , http://hdl.handle.net/10962/d1005618
- Description: The variations in the composition, specifically the Cr20 S content and the Cr:Fe ratio, and the morphology of the Lower Group (LG) and Middle Group (MG) chromitite seams of the Critical Zone (CZ) across the western Bushveld Complex, including the Ruighoek and Brits sections, is investigated by means of whole-rock chemical data, both major and trace elements analysis, XRD and electron microprobe data. As a result ofthe paucity of exposed or developed LG1 - LG5 chromitite seams in the western Bushveld Complex, this study is confined to the investigation of the compositional variations of the LG6 to MG4 chromitite seams. In only one section, the Ruighoek section, was the entire succession of chromitite seams, from the LG1 - MG4, exposed. The silicate host rocks from the LG6 pyroxenite footwall to the collar of the CC2 drillcore (lower uCZ) in the Rustenburg section were sampled. This study reviews the compositional trends of the silicate host rocks, as the compositional variations of the chromitite seams reflect the chemical evolution of the host cumulate environment and, to a lesser degree, the composition onhe interstitial mineral phases in the chromitite seams. The compositional variations of the LG and MG chromitite seams are attributed to the compositional contrast between the replenishing magma and the resident magma. The chemical trends of the LG and MG chromitite layers and the host cumUlate rOCKS do not support the existence of two compositionalfy dissimilar magmas in the CZ, rather the cyclic layering of the CZ and the chemical variations of the chromitite seams are attributed to the mixing of primitive magma with the resident magma, both of which have essentially similar compositions. The compositional variations of the LG and MG chromitite seams along strike away from the supposed feeder site (Union section) to the distal facies (Brits section) are attributed to the advanced compositional contrast between the resident magma and the replenishing primitive magma pulses. The CZ is characterized by reversals in fractionation trends and this is attributed to the compositional evolution of the parental magma and not to the replenishment of the resident magma by influxes of grossly dissimilar magma compositions. The Cr20 S content and the Cr:Fe ratio of the MG chromitite layers increase from the Ruighoek (near proximal) section to the Brits section (distal facies). This is attributed to the advanced compositional contrasts between the resident magma and the replenishing primitive magma. In contrast, the Cr20 3 content and Cr:Fe ratios ofthe LG6 and LG8a chromitite seams decreases eastwards from the Ruighoek section. The average Cr:Fe ratio for the western Bushveld Complex is between 1.5 and\2.0, nonetheless, a progressively lower Cr:Fe ratio is noted from the LG1 chromitite up through to the MG4 chromitite seam in the Ruighoek section. tn the LG2 - LG4 chromitite interval a deviation to higher.lratios is encountered. A progressive substitution of Cr by AT and Fe in the Cr-spinel crystal lattice characterizes the chromitite succession from the LG1 seam up through the chromitite succession to MG4. The petrogeneSiS of the chromitite seams of the CZ is attributed to magma mixing and fractional crystallization of a single magma type.
- Full Text:
- Date Issued: 2000
An investigation into short course accreditation through the South African Qualification Authority
- Authors: Mackenzie, Ian
- Date: 2000
- Subjects: Adult education -- South Africa Elementary education of adults -- South Africa School management and organization -- South Africa Guguletu Comprehensive School South African Qualifications Authority
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1600 , http://hdl.handle.net/10962/d1003482
- Description: This research project offers an analysis of the Adult Basic Education and Training Directorate in the Eastern Cape Province. The Bush Models are described and critiqued and then used as a tool for analysis. Other organisational models are described and used to add depth to the analysis. The choice of analysing the Adult Basic Education and Training Directorate comes both from a professional desire to know and understand this organisation more fully, as well as the importance of stressing that the definition of education organisations does not stop at school, colleges and universities, but includes the government bodies which are a key part of the sector. This assignment therefore explores both the features of a government department as well as the appropriateness of using Bush’s models in this context and draws on other organisational theory--Introduction.
- Full Text:
- Date Issued: 2000
- Authors: Mackenzie, Ian
- Date: 2000
- Subjects: Adult education -- South Africa Elementary education of adults -- South Africa School management and organization -- South Africa Guguletu Comprehensive School South African Qualifications Authority
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1600 , http://hdl.handle.net/10962/d1003482
- Description: This research project offers an analysis of the Adult Basic Education and Training Directorate in the Eastern Cape Province. The Bush Models are described and critiqued and then used as a tool for analysis. Other organisational models are described and used to add depth to the analysis. The choice of analysing the Adult Basic Education and Training Directorate comes both from a professional desire to know and understand this organisation more fully, as well as the importance of stressing that the definition of education organisations does not stop at school, colleges and universities, but includes the government bodies which are a key part of the sector. This assignment therefore explores both the features of a government department as well as the appropriateness of using Bush’s models in this context and draws on other organisational theory--Introduction.
- Full Text:
- Date Issued: 2000
Exploitation patterns of the multi species/gear hake (Merluccius capensis and paradoxus) fishery on South Africa's southeast coast
- Authors: Sutton, Glen Robert
- Date: 2000
- Subjects: Fishing -- South Africa , Hake -- South Africa , Merluccius capensis -- South Africa , Merluccius paradoxus -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5280 , http://hdl.handle.net/10962/d1005124 , Fishing -- South Africa , Hake -- South Africa , Merluccius capensis -- South Africa , Merluccius paradoxus -- South Africa
- Description: The motivation for this study was to examine the exploitation patterns of the M. capensis and M. paradoxus hake fisheries on the Southeast Coast, and determine the size and species of hake caught in each of the hand-line, long-line, and trawl methods. The handline hake fishery has increased substantially over the last several years and concerns are beginning to emerge about the impact this will have on the inshore resource collected on the South Coast between August 1998 and July 1999 was used to describe the hand-line method and estimate annual landings. Data on the size and species in longline catches of hake caught during 1997 were already available for this study. Size distributions in trawl catches were determined from commercial category landing data reported by catch weight and depth. The species composition in these catches determined by comparison using RV Afrikana survey data collected in the same depth regions. Location plays a significant role in determining the sizes and species of hake caught by each gear. Hand-lines catch smaller sizes on average than do long-lines, inshore trawls target mainly M. capensis while offshore trawls catch both hake species. A substantial amount of the hand-line hake caught on the South Coast is not reported. Examination of the exploitation patterns reveal that intense trawling pressure is directed at the smaller sized M. paradoxus inhabiting the depth region between 160-400-meters. Inshore trawls discard a large amount of small sized M. capensis within the 100-meter isobath. A preliminary stock assessment on the status of each hake species found that M. paradoxus appears to be over-exploited while M. capensis was in better shape. However, length-based pseudo-cohort analysis, used in this assessment, is critically reliant on having length frequency data from a steady state population in equilibrium. This limits the application of this model for management purposes and this finding is purely theoretical at this stage. Results suggest that each hake species is under a different pattern and level of exploitation and the multi-species nature of hake stocks on the South Coast should be considered in developing optimum management policies. Future work should focus on developing appropriate age/length keys so that an age-based VPA, which is more powerful than the length-based approach, can be applied towards stock assessments on the South Coast. Alternatively, length-data covering a longer period should be compiled and the equilibrium assumption further investigated so that the results from length-based models can be used with more confidence.
- Full Text:
- Date Issued: 2000
- Authors: Sutton, Glen Robert
- Date: 2000
- Subjects: Fishing -- South Africa , Hake -- South Africa , Merluccius capensis -- South Africa , Merluccius paradoxus -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5280 , http://hdl.handle.net/10962/d1005124 , Fishing -- South Africa , Hake -- South Africa , Merluccius capensis -- South Africa , Merluccius paradoxus -- South Africa
- Description: The motivation for this study was to examine the exploitation patterns of the M. capensis and M. paradoxus hake fisheries on the Southeast Coast, and determine the size and species of hake caught in each of the hand-line, long-line, and trawl methods. The handline hake fishery has increased substantially over the last several years and concerns are beginning to emerge about the impact this will have on the inshore resource collected on the South Coast between August 1998 and July 1999 was used to describe the hand-line method and estimate annual landings. Data on the size and species in longline catches of hake caught during 1997 were already available for this study. Size distributions in trawl catches were determined from commercial category landing data reported by catch weight and depth. The species composition in these catches determined by comparison using RV Afrikana survey data collected in the same depth regions. Location plays a significant role in determining the sizes and species of hake caught by each gear. Hand-lines catch smaller sizes on average than do long-lines, inshore trawls target mainly M. capensis while offshore trawls catch both hake species. A substantial amount of the hand-line hake caught on the South Coast is not reported. Examination of the exploitation patterns reveal that intense trawling pressure is directed at the smaller sized M. paradoxus inhabiting the depth region between 160-400-meters. Inshore trawls discard a large amount of small sized M. capensis within the 100-meter isobath. A preliminary stock assessment on the status of each hake species found that M. paradoxus appears to be over-exploited while M. capensis was in better shape. However, length-based pseudo-cohort analysis, used in this assessment, is critically reliant on having length frequency data from a steady state population in equilibrium. This limits the application of this model for management purposes and this finding is purely theoretical at this stage. Results suggest that each hake species is under a different pattern and level of exploitation and the multi-species nature of hake stocks on the South Coast should be considered in developing optimum management policies. Future work should focus on developing appropriate age/length keys so that an age-based VPA, which is more powerful than the length-based approach, can be applied towards stock assessments on the South Coast. Alternatively, length-data covering a longer period should be compiled and the equilibrium assumption further investigated so that the results from length-based models can be used with more confidence.
- Full Text:
- Date Issued: 2000