Teachers' talk regarding inclusion: a comparative discursive study
- Authors: Bomela, Yolisa Faith
- Date: 2006
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3123 , http://hdl.handle.net/10962/d1006135
- Description: Much research on the educators' perceptions of and attitudes towards inclusive education has been conducted both in South Africa and abroad. What is absent in this literature is an acknowledgement of the socially constructed nature of teachers' responses to inclusive education and its recipients. In this study, the talk of educators involved in piloting inclusive education is compared to that of educators who are not involved, in order to determine the discourses from which educators draw in their construction of inclusive education. It is a comparative study premised on the social constructionist perspective in which discourse analysis was employed. The sample was drawn from schools piloting inclusive education in the East London District of the Eastern Cape Province in South Africa and was compared with schools not involved in the pilot, but in the same area. Semi- structured interviews were conducted with eight educators spread across two piloting and two non piloting schools. The analysis revealed significant similarities and quite minimal differences in the manner in which educators across the two settings construct their experiences of inclusive education. Even though the educators draw on the rights driven anti-discriminatory discourse, they still embrace the special needs/medical/expertise and charity discourses. These discourses construct disability around notions of disputed degrees of impairment, feared status and perceptions of disability as a personal issue rather than a public responsibility, and they undermine the status of people with a disability while supporting notions of dependency. In this article, I will argue that the historical legacy within which these discourses were originally constructed, will essentially continue unless there is a change in how diversity is viewed.
- Full Text:
- Date Issued: 2006
- Authors: Bomela, Yolisa Faith
- Date: 2006
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3123 , http://hdl.handle.net/10962/d1006135
- Description: Much research on the educators' perceptions of and attitudes towards inclusive education has been conducted both in South Africa and abroad. What is absent in this literature is an acknowledgement of the socially constructed nature of teachers' responses to inclusive education and its recipients. In this study, the talk of educators involved in piloting inclusive education is compared to that of educators who are not involved, in order to determine the discourses from which educators draw in their construction of inclusive education. It is a comparative study premised on the social constructionist perspective in which discourse analysis was employed. The sample was drawn from schools piloting inclusive education in the East London District of the Eastern Cape Province in South Africa and was compared with schools not involved in the pilot, but in the same area. Semi- structured interviews were conducted with eight educators spread across two piloting and two non piloting schools. The analysis revealed significant similarities and quite minimal differences in the manner in which educators across the two settings construct their experiences of inclusive education. Even though the educators draw on the rights driven anti-discriminatory discourse, they still embrace the special needs/medical/expertise and charity discourses. These discourses construct disability around notions of disputed degrees of impairment, feared status and perceptions of disability as a personal issue rather than a public responsibility, and they undermine the status of people with a disability while supporting notions of dependency. In this article, I will argue that the historical legacy within which these discourses were originally constructed, will essentially continue unless there is a change in how diversity is viewed.
- Full Text:
- Date Issued: 2006
Maximum likelihood and Bayesian approaches to stock assessment when data are questionable
- Booth, Anthony J, Quinn II, T J
- Authors: Booth, Anthony J , Quinn II, T J
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6764 , http://hdl.handle.net/10962/d1007962
- Description: This study examines the use of age-structured maximum likelihood and Bayesian approaches for stock assessment of the Namibian monkfish, Lophius vomerinus, resource with questionable data, in which time series are short, abundance indices are variable, and research data conflict with commercial data. Bayesian approaches with both noninformative and informative priors are investigated to determine if they enhance estimation stability. Three data scenarios are assessed: commercial and research survey data, research survey data only, and commercial data only. Both statistical approaches show that resource abundance has decreased with exploitable biomass estimated at approximately 44% of pristine levels. The maximum likelihood and the Bayesian approach with noninformative priors result in similar estimates. As the abundance data contained little information pertaining to possible density dependence within the stock–recruit relationship, only a Bayesian approach with informative priors reduces uncertainty in the steepness parameter h. Estimated management quantities are sensitive both to the set of data sources and whether prior information was informative or not. The strengths of the Bayesian approach include the integration of prior information with uncertain data, the exploration of data conflicts, and the ability to show the uncertainty in estimates of management parameters. Its weakness is that estimation stability is dependent on the choice of priors, which alters some posterior distributions of management quantities.
- Full Text:
- Date Issued: 2006
- Authors: Booth, Anthony J , Quinn II, T J
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6764 , http://hdl.handle.net/10962/d1007962
- Description: This study examines the use of age-structured maximum likelihood and Bayesian approaches for stock assessment of the Namibian monkfish, Lophius vomerinus, resource with questionable data, in which time series are short, abundance indices are variable, and research data conflict with commercial data. Bayesian approaches with both noninformative and informative priors are investigated to determine if they enhance estimation stability. Three data scenarios are assessed: commercial and research survey data, research survey data only, and commercial data only. Both statistical approaches show that resource abundance has decreased with exploitable biomass estimated at approximately 44% of pristine levels. The maximum likelihood and the Bayesian approach with noninformative priors result in similar estimates. As the abundance data contained little information pertaining to possible density dependence within the stock–recruit relationship, only a Bayesian approach with informative priors reduces uncertainty in the steepness parameter h. Estimated management quantities are sensitive both to the set of data sources and whether prior information was informative or not. The strengths of the Bayesian approach include the integration of prior information with uncertain data, the exploration of data conflicts, and the ability to show the uncertainty in estimates of management parameters. Its weakness is that estimation stability is dependent on the choice of priors, which alters some posterior distributions of management quantities.
- Full Text:
- Date Issued: 2006
Diasporic consciousness and Bollywood : South African Indian youth and the meanings they make of Indian film
- Authors: Boshoff, Priscilla
- Date: 2006
- Subjects: Motion pictures -- India , Youth -- South Africa -- Attitudes , East Indians -- South Africa -- Attitudes , Motion picture industry -- India -- Mumbai
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3503 , http://hdl.handle.net/10962/d1006249 , Motion pictures -- India , Youth -- South Africa -- Attitudes , East Indians -- South Africa -- Attitudes , Motion picture industry -- India -- Mumbai
- Description: A particular youth identity in the South African Indian diaspora is being forged in a nexus o flocal and global forces . The globalisation of Bollywood and its popularity as a global media and the international commodification of the Indian exotic have occurred at the same time as the valorisation of 'difference' in the local political landscape. Indian youth, as young members of the South African Indian diaspora, are inheritors both of a conservative - yet adaptable - home culture and the marginalised identities of apartheid. However, the tensions between their desire to be recognised as both 'modern' South Africans and as ' traditional ' Indians create a space in which they are able to (re)create for themselves an identity that can encompass both their home cultures and the desires of a Westernised modernity through the tropes of Bollywood. Bollywood speaks to its diasporic audiences through representations of an idealised 'traditional yet modern' India. Although India is not a place of return for this young generation, Bollywood representations of successful diasporic Indian culture and participation in the globalised Bollywood industry through concerts and international award ceremonies has provided an opportunity for young Indians in South Africa to re-examine their local Indian identities and feel invited to re-identify with the global diasporas of India.
- Full Text:
- Date Issued: 2006
- Authors: Boshoff, Priscilla
- Date: 2006
- Subjects: Motion pictures -- India , Youth -- South Africa -- Attitudes , East Indians -- South Africa -- Attitudes , Motion picture industry -- India -- Mumbai
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3503 , http://hdl.handle.net/10962/d1006249 , Motion pictures -- India , Youth -- South Africa -- Attitudes , East Indians -- South Africa -- Attitudes , Motion picture industry -- India -- Mumbai
- Description: A particular youth identity in the South African Indian diaspora is being forged in a nexus o flocal and global forces . The globalisation of Bollywood and its popularity as a global media and the international commodification of the Indian exotic have occurred at the same time as the valorisation of 'difference' in the local political landscape. Indian youth, as young members of the South African Indian diaspora, are inheritors both of a conservative - yet adaptable - home culture and the marginalised identities of apartheid. However, the tensions between their desire to be recognised as both 'modern' South Africans and as ' traditional ' Indians create a space in which they are able to (re)create for themselves an identity that can encompass both their home cultures and the desires of a Westernised modernity through the tropes of Bollywood. Bollywood speaks to its diasporic audiences through representations of an idealised 'traditional yet modern' India. Although India is not a place of return for this young generation, Bollywood representations of successful diasporic Indian culture and participation in the globalised Bollywood industry through concerts and international award ceremonies has provided an opportunity for young Indians in South Africa to re-examine their local Indian identities and feel invited to re-identify with the global diasporas of India.
- Full Text:
- Date Issued: 2006
Ionospheric total electron content variability and its influence in radio astronomy
- Authors: Botai, Ondego Joel
- Date: 2006
- Subjects: Electrons , Global Positioning System , Global Positioning System -- Data processing , Ionosphere , Ionospheric radio wave propagation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5473 , http://hdl.handle.net/10962/d1005258 , Electrons , Global Positioning System , Global Positioning System -- Data processing , Ionosphere , Ionospheric radio wave propagation
- Description: Ionospheric phase delays of radio signals from Global Positioning System (GPS) satellites have been used to compute ionospheric Total Electron Content (TEC). An extended Chapman profle model is used to estimate the electron density profles and TEC. The Chapman profle that can be used to predict TEC over the mid-latitudes only applies during day time. To model night time TEC variability, a polynomial function is fitted to the night time peak electron density profles derived from the online International Reference Ionosphere (IRI) 2001. The observed and predicted TEC and its variability have been used to study ionospheric in°uence on Radio Astronomy in South Africa region. Di®erential phase delays of the radio signals from Radio Astronomy sources have been simulated using TEC. Using the simulated phase delays, the azimuth and declination o®sets of the radio sources have been estimated. Results indicate that, pointing errors of the order of miliarcseconds (mas) are likely if the ionospheric phase delays are not corrected for. These delays are not uniform and vary over a broad spectrum of timescales. This implies that fast frequency (referencing) switching, closure phases and fringe ¯tting schemes for ionospheric correction in astrometry are not the best option as they do not capture the real state of the ionosphere especially if the switching time is greater than the ionospheric TEC variability. However, advantage can be taken of the GPS satellite data available at intervals of a second from the GPS receiver network in South Africa to derive parameters which could be used to correct for the ionospheric delays. Furthermore GPS data can also be used to monitor the occurrence of scintillations, (which might corrupt radio signals) especially for the proposed, Square Kilometer Array (SKA) stations closer to the equatorial belt during magnetic storms and sub-storms. A 10 minute snapshot of GPS data recorded with the Hermanus [34:420 S, 19:220 E ] dual frequency receiver on 2003-04-11 did not show the occurrence of scintillations. This time scale is however too short and cannot be representative. Longer time scales; hours, days, seasons are needed to monitor the occurrence of scintillations.
- Full Text:
- Date Issued: 2006
- Authors: Botai, Ondego Joel
- Date: 2006
- Subjects: Electrons , Global Positioning System , Global Positioning System -- Data processing , Ionosphere , Ionospheric radio wave propagation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5473 , http://hdl.handle.net/10962/d1005258 , Electrons , Global Positioning System , Global Positioning System -- Data processing , Ionosphere , Ionospheric radio wave propagation
- Description: Ionospheric phase delays of radio signals from Global Positioning System (GPS) satellites have been used to compute ionospheric Total Electron Content (TEC). An extended Chapman profle model is used to estimate the electron density profles and TEC. The Chapman profle that can be used to predict TEC over the mid-latitudes only applies during day time. To model night time TEC variability, a polynomial function is fitted to the night time peak electron density profles derived from the online International Reference Ionosphere (IRI) 2001. The observed and predicted TEC and its variability have been used to study ionospheric in°uence on Radio Astronomy in South Africa region. Di®erential phase delays of the radio signals from Radio Astronomy sources have been simulated using TEC. Using the simulated phase delays, the azimuth and declination o®sets of the radio sources have been estimated. Results indicate that, pointing errors of the order of miliarcseconds (mas) are likely if the ionospheric phase delays are not corrected for. These delays are not uniform and vary over a broad spectrum of timescales. This implies that fast frequency (referencing) switching, closure phases and fringe ¯tting schemes for ionospheric correction in astrometry are not the best option as they do not capture the real state of the ionosphere especially if the switching time is greater than the ionospheric TEC variability. However, advantage can be taken of the GPS satellite data available at intervals of a second from the GPS receiver network in South Africa to derive parameters which could be used to correct for the ionospheric delays. Furthermore GPS data can also be used to monitor the occurrence of scintillations, (which might corrupt radio signals) especially for the proposed, Square Kilometer Array (SKA) stations closer to the equatorial belt during magnetic storms and sub-storms. A 10 minute snapshot of GPS data recorded with the Hermanus [34:420 S, 19:220 E ] dual frequency receiver on 2003-04-11 did not show the occurrence of scintillations. This time scale is however too short and cannot be representative. Longer time scales; hours, days, seasons are needed to monitor the occurrence of scintillations.
- Full Text:
- Date Issued: 2006
Assessing the impact of the lean manufacturing supplier development practices of an Eastern Cape vehicle manufacturer
- Authors: Botha, Christo Johannes
- Date: 2006
- Subjects: Production management , Automobile industry and trade -- South Africa -- Eastern Cape , Industrial procurement
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8558 , http://hdl.handle.net/10948/480 , Production management , Automobile industry and trade -- South Africa -- Eastern Cape , Industrial procurement
- Description: The world automotive industry has evolved through different manufacturing methodologies over many decades. It originated from craft production, but was transformed to mass production by Henry Ford in response to increased market demand. The methodology developed by Henry Ford made it possible to produce quality vehicles in large numbers and at affordable cost to the general public. However, it cannot deliver a great variety of products to the marketplace. Mass production was overtaken by a new automotive manufacturing methodology developed in Japan after World War II. The methodology, commonly referred to as lean production, yields consistently high quality products at even lower costs, whilst being able to deliver a variety of products to the consumer. The effectiveness of the lean production methodology hinges upon the strength and closeness of the relationships that exist between the assembler and its suppliers. Different models have been developed over time to describe the relationships between automotive assemblers and their suppliers. The lean supply model is generally accepted as an effective way of describing the relationships that exist between an automotive assembler and its first tier suppliers in a lean manufacturing environment. The research study aims at gaining an improved understanding of the relationships that exist between a selected Eastern Cape automotive assembler and its first tier suppliers. The effect of its supplier support practices towards lean manufacturing implementation amongst its first tier suppliers is evaluated. For the selected assembler it is found that the effect of its supplier support practices on lean manufacturing implementation amongst its first tier suppliers is limited by a non-uniform approach followed towards the supplier base. It is shown that opportunities for improvement exist for the selected assembler to develop closer relationships with its first tier suppliers to increase its global competitiveness.
- Full Text:
- Date Issued: 2006
- Authors: Botha, Christo Johannes
- Date: 2006
- Subjects: Production management , Automobile industry and trade -- South Africa -- Eastern Cape , Industrial procurement
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8558 , http://hdl.handle.net/10948/480 , Production management , Automobile industry and trade -- South Africa -- Eastern Cape , Industrial procurement
- Description: The world automotive industry has evolved through different manufacturing methodologies over many decades. It originated from craft production, but was transformed to mass production by Henry Ford in response to increased market demand. The methodology developed by Henry Ford made it possible to produce quality vehicles in large numbers and at affordable cost to the general public. However, it cannot deliver a great variety of products to the marketplace. Mass production was overtaken by a new automotive manufacturing methodology developed in Japan after World War II. The methodology, commonly referred to as lean production, yields consistently high quality products at even lower costs, whilst being able to deliver a variety of products to the consumer. The effectiveness of the lean production methodology hinges upon the strength and closeness of the relationships that exist between the assembler and its suppliers. Different models have been developed over time to describe the relationships between automotive assemblers and their suppliers. The lean supply model is generally accepted as an effective way of describing the relationships that exist between an automotive assembler and its first tier suppliers in a lean manufacturing environment. The research study aims at gaining an improved understanding of the relationships that exist between a selected Eastern Cape automotive assembler and its first tier suppliers. The effect of its supplier support practices towards lean manufacturing implementation amongst its first tier suppliers is evaluated. For the selected assembler it is found that the effect of its supplier support practices on lean manufacturing implementation amongst its first tier suppliers is limited by a non-uniform approach followed towards the supplier base. It is shown that opportunities for improvement exist for the selected assembler to develop closer relationships with its first tier suppliers to increase its global competitiveness.
- Full Text:
- Date Issued: 2006
Habitat segregation in competing species of intertidal mussels in South Africa
- Authors: Bownes, Sarah
- Date: 2006
- Subjects: Mussels -- South Africa Mussels -- Growth Mussels -- Habitat -- South Africa Mussels -- Larvae Perna -- South Africa Mytilus galloprovincialis -- South Africa Choromytilus meridionalis -- South Africa Mytilidae -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5706 , http://hdl.handle.net/10962/d1005392
- Description: Mytilus galloprovincialis is invasive on rocky shores on the west coast of South Africa where it has become the dominant intertidal mussel. The success of this species on the west coast and its superior competitive abilities, have led to concern that it may become invasive on the south coast at the expense of the indigenous mussel Perna perna. On shores where these species co-occur, there appears to be habitat segregation among zones occupied by mussels. M.galloprovincialis dominates the high-shore and P.perna the low-shore, with a mixed zone at mid-shore level. This study examined the factors responsible for these differences in distribution and abundance. The study was conducted in Plettenberg Bay and Tsitsikamma (70km apart) on the south coast of South Africa. Each site included two randomly selected locations (300-400m apart). A third mussel species, Choromytilus meridionalis, is found in large numbers at the sand/rock interface at one location in Plettenberg Bay. Aspects of settlement, recruitment, growth and mortality of juvenile and adult mussels were examined at different tidal heights at each site. Quantitative analysis of mussel population structure at these sites supported the initial observation of vertical habitat segregation. Post-larvae were identified to species and this was confirmed using hinge morphology and mitochondrial DNA analysis. Size at settlement was determined for each species to differentiate between primary and secondary settlement. Adult distribution of C.meridionalis was primarily determined by settlement, which was highly selective in this species. Settlement, recruitment and growth of P.perna decreased with increasing tidal height, while post-settlement mortality and adult mortality increased higher upshore. Thus all aspects of P.perna’s life history contribute to the adult distribution of this species. Presumably, the abundance of P.perna on the high-shore is initially limited by recruitment while those that survive remain prone to elimination throughout adulthood. M.galloprovincialis displayed the same patterns of settlement and recruitment as P.perna. However, post-settlement mortality in this species was consistently low in the low and high zones. Juvenile growth also decreased upshore, suggesting that M.galloprovincialis may be able to maintain high densities on the high-shore through the persistence of successive settlements of slow-growing individuals. The low cover of M.galloprovincialis on the lowshore appeared to be determined by adult interactions. M.galloprovincialis experienced significantly higher adult mortality rates than P.perna in this zone. There were seasonal variations in the competitive advantages enjoyed by each species through growth, recruitment or mortality on the low-shore. In summer, P.perna had higher recruitment rates, faster growth and lower mortality rates, while M.galloprovincialis had slightly higher recruitment rates and faster growth rates in winter. P.perna is a warm water species while M.galloprovincialis thrives on the cold-temperate west coast of South Africa. Therefore both species appear to be at the edge of their optimal temperature regimes on the south coast, which may explain the seasonal advantages of each. Nevertheless, P.perna has maintained spatial dominance on the low-shore suggesting that it may ultimately be the winner in competition between these species. M.galloprovincialis appears to have a refuge from competition with P.perna on the high-shore due to its greater tolerance of desiccation stress, while being competitively excluded from the low-shore. Warm water temperatures coupled with poor recruitment rates at most sites may limit the success of M.galloprovincialis on this coast.
- Full Text:
- Date Issued: 2006
- Authors: Bownes, Sarah
- Date: 2006
- Subjects: Mussels -- South Africa Mussels -- Growth Mussels -- Habitat -- South Africa Mussels -- Larvae Perna -- South Africa Mytilus galloprovincialis -- South Africa Choromytilus meridionalis -- South Africa Mytilidae -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5706 , http://hdl.handle.net/10962/d1005392
- Description: Mytilus galloprovincialis is invasive on rocky shores on the west coast of South Africa where it has become the dominant intertidal mussel. The success of this species on the west coast and its superior competitive abilities, have led to concern that it may become invasive on the south coast at the expense of the indigenous mussel Perna perna. On shores where these species co-occur, there appears to be habitat segregation among zones occupied by mussels. M.galloprovincialis dominates the high-shore and P.perna the low-shore, with a mixed zone at mid-shore level. This study examined the factors responsible for these differences in distribution and abundance. The study was conducted in Plettenberg Bay and Tsitsikamma (70km apart) on the south coast of South Africa. Each site included two randomly selected locations (300-400m apart). A third mussel species, Choromytilus meridionalis, is found in large numbers at the sand/rock interface at one location in Plettenberg Bay. Aspects of settlement, recruitment, growth and mortality of juvenile and adult mussels were examined at different tidal heights at each site. Quantitative analysis of mussel population structure at these sites supported the initial observation of vertical habitat segregation. Post-larvae were identified to species and this was confirmed using hinge morphology and mitochondrial DNA analysis. Size at settlement was determined for each species to differentiate between primary and secondary settlement. Adult distribution of C.meridionalis was primarily determined by settlement, which was highly selective in this species. Settlement, recruitment and growth of P.perna decreased with increasing tidal height, while post-settlement mortality and adult mortality increased higher upshore. Thus all aspects of P.perna’s life history contribute to the adult distribution of this species. Presumably, the abundance of P.perna on the high-shore is initially limited by recruitment while those that survive remain prone to elimination throughout adulthood. M.galloprovincialis displayed the same patterns of settlement and recruitment as P.perna. However, post-settlement mortality in this species was consistently low in the low and high zones. Juvenile growth also decreased upshore, suggesting that M.galloprovincialis may be able to maintain high densities on the high-shore through the persistence of successive settlements of slow-growing individuals. The low cover of M.galloprovincialis on the lowshore appeared to be determined by adult interactions. M.galloprovincialis experienced significantly higher adult mortality rates than P.perna in this zone. There were seasonal variations in the competitive advantages enjoyed by each species through growth, recruitment or mortality on the low-shore. In summer, P.perna had higher recruitment rates, faster growth and lower mortality rates, while M.galloprovincialis had slightly higher recruitment rates and faster growth rates in winter. P.perna is a warm water species while M.galloprovincialis thrives on the cold-temperate west coast of South Africa. Therefore both species appear to be at the edge of their optimal temperature regimes on the south coast, which may explain the seasonal advantages of each. Nevertheless, P.perna has maintained spatial dominance on the low-shore suggesting that it may ultimately be the winner in competition between these species. M.galloprovincialis appears to have a refuge from competition with P.perna on the high-shore due to its greater tolerance of desiccation stress, while being competitively excluded from the low-shore. Warm water temperatures coupled with poor recruitment rates at most sites may limit the success of M.galloprovincialis on this coast.
- Full Text:
- Date Issued: 2006
Will the invasive mussel Mytilus galloprovincialis Lamarck replace the indigenous Perna perna L. on the south coast of South Africa?
- Bownes, Sarah J, McQuaid, Christopher D
- Authors: Bownes, Sarah J , McQuaid, Christopher D
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6926 , http://hdl.handle.net/10962/d1011914
- Description: The mussel Mytilus galloprovincialis is invasive worldwide, has displaced indigenous species on the west coast of South Africa and now threatens Perna perna on the south coast. We tested the hypothesis that Mytilus will replace Perna by examining changes in their distribution on shores where they co-exist. Total cover, adult density, recruit density, recruit/adult correlations and mean maximum lengths of both species were measured in 2001 at two contrasting sites (Plettenberg Bay and Tsitsikamma) 70 km apart, each including two locations 100 m apart. Cover and density were measured again in 2004. Total mussel abundance was significantly lower in Tsitsikamma, and recruit density was only 17% that of Plettenberg Bay. Abundance and cover increased upshore for Mytilus, but decreased for Perna, giving Mytilus higher adult and recruit density and total cover than Perna in the upper zones. Low shore densities of recruits and adults were similar between species but cover was lower for Mytilus, reflecting its smaller size, and presumably slower growth or higher mortality there. Thus, mechanisms excluding species differed among zones. Recruitment limitation delays invasion at Tsitsikamma and excludes Perna from the high shore, while Mytilus is excluded from the low shore by post-recruitment effects. Recruitment limitation also shapes population structure. Recruit/adult correlations were significant only where adult densities were low, and this effect was species-specific. Thus, at low densities, larvae settle or survive better near adult conspecifics. After 3 years, these patterns remained strongly evident, suggesting Mytilus will not eliminate Perna and that co-existence is possible through partial habitat segregation driven by recruitment limitation of Perna on the high shore and post-settlement effects on Mytilus on the low shore.
- Full Text:
- Date Issued: 2006
- Authors: Bownes, Sarah J , McQuaid, Christopher D
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6926 , http://hdl.handle.net/10962/d1011914
- Description: The mussel Mytilus galloprovincialis is invasive worldwide, has displaced indigenous species on the west coast of South Africa and now threatens Perna perna on the south coast. We tested the hypothesis that Mytilus will replace Perna by examining changes in their distribution on shores where they co-exist. Total cover, adult density, recruit density, recruit/adult correlations and mean maximum lengths of both species were measured in 2001 at two contrasting sites (Plettenberg Bay and Tsitsikamma) 70 km apart, each including two locations 100 m apart. Cover and density were measured again in 2004. Total mussel abundance was significantly lower in Tsitsikamma, and recruit density was only 17% that of Plettenberg Bay. Abundance and cover increased upshore for Mytilus, but decreased for Perna, giving Mytilus higher adult and recruit density and total cover than Perna in the upper zones. Low shore densities of recruits and adults were similar between species but cover was lower for Mytilus, reflecting its smaller size, and presumably slower growth or higher mortality there. Thus, mechanisms excluding species differed among zones. Recruitment limitation delays invasion at Tsitsikamma and excludes Perna from the high shore, while Mytilus is excluded from the low shore by post-recruitment effects. Recruitment limitation also shapes population structure. Recruit/adult correlations were significant only where adult densities were low, and this effect was species-specific. Thus, at low densities, larvae settle or survive better near adult conspecifics. After 3 years, these patterns remained strongly evident, suggesting Mytilus will not eliminate Perna and that co-existence is possible through partial habitat segregation driven by recruitment limitation of Perna on the high shore and post-settlement effects on Mytilus on the low shore.
- Full Text:
- Date Issued: 2006
Intersubjectivity and the schizophrenic experience: a hermeneutic phenomoneological exploration of being-in-relation
- Bradfield, Bruce Christopher
- Authors: Bradfield, Bruce Christopher
- Date: 2006
- Subjects: Schizophrenia , Intersubjectivity
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2940 , http://hdl.handle.net/10962/d1002449 , Schizophrenia , Intersubjectivity
- Description: This research project has its origin and motivation in work done by Lysaker, Johannesen and Lysaker (2005), which explored the experience of being as a person with schizophrenia in relation to other individuals. The researchers examined the nature of the schizophrenic experience from within the framework of the dialogical model of self, and presented schizophrenic intersubjectivity as a potentially horrifying and disintegrating experience. Lysaker et al (2005) discuss the notion that the individual self unfolds as a composite structure of multiple selves, existing in dialogical interaction with one another. Their research aimed to show that the individual with schizophrenia experiences difficulty tolerating this dialogue on an intrapsychic level. Because interpersonal exchange requires that individuals adopt a variety of self-other modes of relatedness, suggest Lysaker et al, interpersonal engagement for the person with schizophrenia is disclosed as profoundly threatening (ibid.) Moving from the above-mentioned research, this project aims through a hermeneutic phenomenological process to clarify and narrate the subtleties of the intersubjective experience, as that experience is disclosed in the lived world of a person with schizophrenia. How does such an individual experience self in relation to other? How does such an individual negotiate their sense of self in terms of their dialogicality? The phenomenological hermeneutic method, as shaped by such theorists as Gadamer (1976), Heidegger (1962) and Buber (1970), will emerge as the interpretive platform upon which these questions are approached.
- Full Text:
- Date Issued: 2006
- Authors: Bradfield, Bruce Christopher
- Date: 2006
- Subjects: Schizophrenia , Intersubjectivity
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2940 , http://hdl.handle.net/10962/d1002449 , Schizophrenia , Intersubjectivity
- Description: This research project has its origin and motivation in work done by Lysaker, Johannesen and Lysaker (2005), which explored the experience of being as a person with schizophrenia in relation to other individuals. The researchers examined the nature of the schizophrenic experience from within the framework of the dialogical model of self, and presented schizophrenic intersubjectivity as a potentially horrifying and disintegrating experience. Lysaker et al (2005) discuss the notion that the individual self unfolds as a composite structure of multiple selves, existing in dialogical interaction with one another. Their research aimed to show that the individual with schizophrenia experiences difficulty tolerating this dialogue on an intrapsychic level. Because interpersonal exchange requires that individuals adopt a variety of self-other modes of relatedness, suggest Lysaker et al, interpersonal engagement for the person with schizophrenia is disclosed as profoundly threatening (ibid.) Moving from the above-mentioned research, this project aims through a hermeneutic phenomenological process to clarify and narrate the subtleties of the intersubjective experience, as that experience is disclosed in the lived world of a person with schizophrenia. How does such an individual experience self in relation to other? How does such an individual negotiate their sense of self in terms of their dialogicality? The phenomenological hermeneutic method, as shaped by such theorists as Gadamer (1976), Heidegger (1962) and Buber (1970), will emerge as the interpretive platform upon which these questions are approached.
- Full Text:
- Date Issued: 2006
Epitaxial growth and characterisation of CuGaS2
- Authors: Branch, Matthew Stewart
- Date: 2006
- Subjects: Epitaxy , Chalcopyrite , Semiconductors
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10541 , http://hdl.handle.net/10948/438 , http://hdl.handle.net/10948/d1012893 , Epitaxy , Chalcopyrite , Semiconductors
- Description: In this work, the growth and characterisation of the chalcopyrite semiconductor CuGaS2 is presented. The purpose of this study is to gain a better understanding of the defect chemistry of this class of materials through a systematic study relating the structural and optical properties to the composition of thin films grown by metalorganic vapour phase epitaxy. Details associated with the optimisation of the growth process are presented in a format relating the changes in the composition and morphology to variations in the growth process. The structural properties of thin films grown on GaAs(001) substrates are described. A dominance of polycrystalline growth is found to occur for Cu-rich material, whereas near-stoichiometric to Ga-rich material is typified by epitaxial growth. Secondary phases are identified by X-ray diffractometry and Raman spectroscopy for severely non-stoichiometric material. In some cases, the formation of the cubic zincblende and CuPt polytype of CuGaS2 are identified by transmission electron microscopy. It will be shown that changes in the Cu/Ga ratio of the solid strongly influence the photoluminescence response of the layers. Weak excitonic luminescence is observed for both slightly Ga-rich and Cu-rich material. Near stoichiometric layers exhibit luminescence centered at ~2.4 eV. Cu-rich layers are dominated by a line occurring at ~2.1 eV, whereas a different line at ~2.25 eV dominates for Ga-rich layers. A clear picture emerges of the radiative mechanisms dominating for Cu-rich and Ga-rich layers.
- Full Text:
- Date Issued: 2006
- Authors: Branch, Matthew Stewart
- Date: 2006
- Subjects: Epitaxy , Chalcopyrite , Semiconductors
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10541 , http://hdl.handle.net/10948/438 , http://hdl.handle.net/10948/d1012893 , Epitaxy , Chalcopyrite , Semiconductors
- Description: In this work, the growth and characterisation of the chalcopyrite semiconductor CuGaS2 is presented. The purpose of this study is to gain a better understanding of the defect chemistry of this class of materials through a systematic study relating the structural and optical properties to the composition of thin films grown by metalorganic vapour phase epitaxy. Details associated with the optimisation of the growth process are presented in a format relating the changes in the composition and morphology to variations in the growth process. The structural properties of thin films grown on GaAs(001) substrates are described. A dominance of polycrystalline growth is found to occur for Cu-rich material, whereas near-stoichiometric to Ga-rich material is typified by epitaxial growth. Secondary phases are identified by X-ray diffractometry and Raman spectroscopy for severely non-stoichiometric material. In some cases, the formation of the cubic zincblende and CuPt polytype of CuGaS2 are identified by transmission electron microscopy. It will be shown that changes in the Cu/Ga ratio of the solid strongly influence the photoluminescence response of the layers. Weak excitonic luminescence is observed for both slightly Ga-rich and Cu-rich material. Near stoichiometric layers exhibit luminescence centered at ~2.4 eV. Cu-rich layers are dominated by a line occurring at ~2.1 eV, whereas a different line at ~2.25 eV dominates for Ga-rich layers. A clear picture emerges of the radiative mechanisms dominating for Cu-rich and Ga-rich layers.
- Full Text:
- Date Issued: 2006
Literacy as a community icon : a critical evaluation of literacy as a community icon in the design of a new public library for Stellenbosch
- Authors: Brand, Jacques Martin
- Date: 2006
- Subjects: Library buildings -- South Africa -- Stellenbosch -- Designs and plans , Public libraries -- South Africa -- Stellenbosch -- Designs and plans
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8153 , http://hdl.handle.net/10948/855 , Library buildings -- South Africa -- Stellenbosch -- Designs and plans , Public libraries -- South Africa -- Stellenbosch -- Designs and plans
- Description: The topic for this thesis is a new main public library for Stellenbosch and the direct urban spaces that support it. The thesis will explore the technical requirements for this type of building as well as the response to a historical urban context.
- Full Text:
- Date Issued: 2006
- Authors: Brand, Jacques Martin
- Date: 2006
- Subjects: Library buildings -- South Africa -- Stellenbosch -- Designs and plans , Public libraries -- South Africa -- Stellenbosch -- Designs and plans
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8153 , http://hdl.handle.net/10948/855 , Library buildings -- South Africa -- Stellenbosch -- Designs and plans , Public libraries -- South Africa -- Stellenbosch -- Designs and plans
- Description: The topic for this thesis is a new main public library for Stellenbosch and the direct urban spaces that support it. The thesis will explore the technical requirements for this type of building as well as the response to a historical urban context.
- Full Text:
- Date Issued: 2006
Models of internet connectivity for secondary schools in the Grahamstown circuit
- Authors: Brandt, Ingrid Gisélle
- Date: 2006
- Subjects: Internet in education -- South Africa -- Grahamstown , Computer networks -- South Africa -- Grahamstown , Information technology -- Study and teaching (Secondary) -- South Africa -- Grahamstown , Information technology -- South Africa -- Grahamstown , Computer-assisted instruction -- South Africa -- Grahamstown , Telecommunication in education -- South Africa -- Grahamstown , Education, Secondary -- South Africa -- Grahamstown -- Data processing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4641 , http://hdl.handle.net/10962/d1006566 , Internet in education -- South Africa -- Grahamstown , Computer networks -- South Africa -- Grahamstown , Information technology -- Study and teaching (Secondary) -- South Africa -- Grahamstown , Information technology -- South Africa -- Grahamstown , Computer-assisted instruction -- South Africa -- Grahamstown , Telecommunication in education -- South Africa -- Grahamstown , Education, Secondary -- South Africa -- Grahamstown -- Data processing
- Description: Information and Communication Technologies (ICTs) are becoming more pervasive in South African schools and are increasingly considered valuable tools in education, promoting the development of higher cognitive processes and allowing teachers and learners access to a plethora of information. This study investigates models of Internet connectivity for secondary schools in the Grahamstown Circuit. The various networking technologies currently available to South African schools, or likely to become available to South African schools in the future, are described along with the telecommunications legislation which governs their use in South Africa. Furthermore, current ICT in education projects taking place in South Africa are described together with current ICT in education policy in South Africa. This information forms the backdrop of a detailed schools survey that was conducted at all the 13 secondary schools in the Grahamstown Circuit and enriched with experimental work in the provision of metropolitan network links to selected schools, mostly via Wi-Fi. The result of the investigation is the proposal of a Grahamstown Circuit Metropolitan Education Network.
- Full Text:
- Date Issued: 2006
- Authors: Brandt, Ingrid Gisélle
- Date: 2006
- Subjects: Internet in education -- South Africa -- Grahamstown , Computer networks -- South Africa -- Grahamstown , Information technology -- Study and teaching (Secondary) -- South Africa -- Grahamstown , Information technology -- South Africa -- Grahamstown , Computer-assisted instruction -- South Africa -- Grahamstown , Telecommunication in education -- South Africa -- Grahamstown , Education, Secondary -- South Africa -- Grahamstown -- Data processing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4641 , http://hdl.handle.net/10962/d1006566 , Internet in education -- South Africa -- Grahamstown , Computer networks -- South Africa -- Grahamstown , Information technology -- Study and teaching (Secondary) -- South Africa -- Grahamstown , Information technology -- South Africa -- Grahamstown , Computer-assisted instruction -- South Africa -- Grahamstown , Telecommunication in education -- South Africa -- Grahamstown , Education, Secondary -- South Africa -- Grahamstown -- Data processing
- Description: Information and Communication Technologies (ICTs) are becoming more pervasive in South African schools and are increasingly considered valuable tools in education, promoting the development of higher cognitive processes and allowing teachers and learners access to a plethora of information. This study investigates models of Internet connectivity for secondary schools in the Grahamstown Circuit. The various networking technologies currently available to South African schools, or likely to become available to South African schools in the future, are described along with the telecommunications legislation which governs their use in South Africa. Furthermore, current ICT in education projects taking place in South Africa are described together with current ICT in education policy in South Africa. This information forms the backdrop of a detailed schools survey that was conducted at all the 13 secondary schools in the Grahamstown Circuit and enriched with experimental work in the provision of metropolitan network links to selected schools, mostly via Wi-Fi. The result of the investigation is the proposal of a Grahamstown Circuit Metropolitan Education Network.
- Full Text:
- Date Issued: 2006
Mapping Grahamstown's security governance network : prospects and problems for democratic policing
- Brereton, Catherine Margaret
- Authors: Brereton, Catherine Margaret
- Date: 2006
- Subjects: Democracy -- South Africa , Police -- South Africa , Police administration -- South Africa -- Grahamstown , Police-community relations -- South Africa -- Grahamstown , Crime prevention -- South Africa -- Grahamstown , Police patrol -- South Africa -- Grahamstown , Private security services -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2851 , http://hdl.handle.net/10962/d1006323 , Democracy -- South Africa , Police -- South Africa , Police administration -- South Africa -- Grahamstown , Police-community relations -- South Africa -- Grahamstown , Crime prevention -- South Africa -- Grahamstown , Police patrol -- South Africa -- Grahamstown , Private security services -- South Africa -- Eastern Cape
- Description: The security of its citizens is often regarded as the democratic state's primary raison d'etre. However, with increasing crime and perceptions of insecurity among citizens, along with actual and perceived state policing inadequacies, citizens around the world have sought to make alternative arrangements for their security. The explosion of private alternatives to state policing has resulted in the need for the replacement of former static definitions of policing by more fluid understandings of what policing entails. Policing is no longer an activity undertaken exclusively by the 'state police.' Policing needs to be understood within a framework which recognises the existence of a variety of state, commercial, community groups and individuals which exist within loose and sometimes informal, sometimes formal, networks to provide for the security of citizens. Preceding the country's transition to democracy in 1994 'state' policing in South Africa was aimed at monitoring and suppressing the black population and as a result it conducted itself in a largely militaristic way. When the government of national unity assumed power in 1994 it was indisputable that the South African Police had to undergo major reform if it was to play an effective, co-operative and accountable role in a democratic South Africa. While state policing has unquestionably undergone enormous changes since the advent of democracy in 1994, so too has non-state policing. It is widely accepted that the dividing line between state and non-state policing in South Africa is increasingly blurred. Policing, by its very nature, holds the potential to threaten democracy. Consequently it is important that policing is democratically controlled. According to the Law Commission of Canada four values and principles - justice, equality, accountability, and efficiency - should support policing in a democracy. This thesis is a case study of policing in Grahamstown, a small city in South Africa's Eastern Cape province. It will be shown that the policing problem that currently plagues Grahamstown, and by extension South Africa, is not simply the result of a shortage of providers but rather a problem of co-coordinating and monitoring security governance to ensure that the city does not further develop into a society where the wealthy have greater access to security than the poor.
- Full Text:
- Date Issued: 2006
- Authors: Brereton, Catherine Margaret
- Date: 2006
- Subjects: Democracy -- South Africa , Police -- South Africa , Police administration -- South Africa -- Grahamstown , Police-community relations -- South Africa -- Grahamstown , Crime prevention -- South Africa -- Grahamstown , Police patrol -- South Africa -- Grahamstown , Private security services -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2851 , http://hdl.handle.net/10962/d1006323 , Democracy -- South Africa , Police -- South Africa , Police administration -- South Africa -- Grahamstown , Police-community relations -- South Africa -- Grahamstown , Crime prevention -- South Africa -- Grahamstown , Police patrol -- South Africa -- Grahamstown , Private security services -- South Africa -- Eastern Cape
- Description: The security of its citizens is often regarded as the democratic state's primary raison d'etre. However, with increasing crime and perceptions of insecurity among citizens, along with actual and perceived state policing inadequacies, citizens around the world have sought to make alternative arrangements for their security. The explosion of private alternatives to state policing has resulted in the need for the replacement of former static definitions of policing by more fluid understandings of what policing entails. Policing is no longer an activity undertaken exclusively by the 'state police.' Policing needs to be understood within a framework which recognises the existence of a variety of state, commercial, community groups and individuals which exist within loose and sometimes informal, sometimes formal, networks to provide for the security of citizens. Preceding the country's transition to democracy in 1994 'state' policing in South Africa was aimed at monitoring and suppressing the black population and as a result it conducted itself in a largely militaristic way. When the government of national unity assumed power in 1994 it was indisputable that the South African Police had to undergo major reform if it was to play an effective, co-operative and accountable role in a democratic South Africa. While state policing has unquestionably undergone enormous changes since the advent of democracy in 1994, so too has non-state policing. It is widely accepted that the dividing line between state and non-state policing in South Africa is increasingly blurred. Policing, by its very nature, holds the potential to threaten democracy. Consequently it is important that policing is democratically controlled. According to the Law Commission of Canada four values and principles - justice, equality, accountability, and efficiency - should support policing in a democracy. This thesis is a case study of policing in Grahamstown, a small city in South Africa's Eastern Cape province. It will be shown that the policing problem that currently plagues Grahamstown, and by extension South Africa, is not simply the result of a shortage of providers but rather a problem of co-coordinating and monitoring security governance to ensure that the city does not further develop into a society where the wealthy have greater access to security than the poor.
- Full Text:
- Date Issued: 2006
Voltammetric analysis of pesticides and their degradation: A case study of Amitraz and its degradants
- Authors: Brimecombe, Rory Dennis
- Date: 2006
- Subjects: Hydrolysis , Biodegradation , Voltammetry , Pesticides -- Biodegradation , Pesticides -- Environmental aspects , Acaricides , Acaricides -- Physiological effect
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4131 , http://hdl.handle.net/10962/d1015724
- Description: Amitraz is a formamide acaricide used predominantly in the control of ectoparasites in livestock and honeybees. Amitraz hydrolysis is rapid and occurs under acidic conditions, exposure to sunlight and biodegradation by microorganisms. The main hydrolysis product of amitraz, 2,4-dimethylaniline, is recalcitrant in the environment and toxic to humans. An electrochemical method for the determination of total amitraz residues and its final breakdown product, 2,4-dimethylaniline, in spent cattle dip, is presented. Cyclic voltammetry at a glassy carbon electrode showed the irreversible oxidation of amitraz and 2,4-dimethylaniline. A limit of detection in the range of 8.5 x 10⁻⁸ M for amitraz and 2 x 10⁻⁸ M for 2,4-dimethylaniline was determined using differential pulse voltammetry. Feasibility studies in which the effect of supporting electrolyte type and pH had on electroanalysis of amitraz and its degradants, showed that pH affects current response as well as the potential at which amitraz and its degradants are oxidised. Britton-Robinson buffer was found to be the most suitable supporting electrolyte for detection of amitraz and its degradants in terms of sensitivity and reproducibility. Studies performed using environmental samples showed that the sensitivity and reproducibility of amitraz and 2,4-dimethylaniline analyses in spent cattle dip were comparable to analyses of amitraz and 2,4-dimethylaniline performed in Britton-Robinson buffer. In addition, the feasibility qf measuring amitraz and 2,4-dimethylaniline in environmental samples was assessed and compared to amitraz and 2,4-dimethylaniline analyses in Britton-Robinson buffer. Amitraz and 2,4-dimethylaniline were readily detectable in milk and honey. Furthermore, it was elucidated that 2,4-dimethylaniline can be metabolised to 3-methylcatechol by Pseudomonas species and the proposed breakdown pathway is presented. The biological degradation of amitraz and subsequent formation of 2,4-dimethylaniline was readily monitored in spent cattle dip. The breakdown of amitraz to 2,4-dimethylaniline and then to 3-MC was monitored using cyclic voltammetry.
- Full Text:
- Date Issued: 2006
- Authors: Brimecombe, Rory Dennis
- Date: 2006
- Subjects: Hydrolysis , Biodegradation , Voltammetry , Pesticides -- Biodegradation , Pesticides -- Environmental aspects , Acaricides , Acaricides -- Physiological effect
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4131 , http://hdl.handle.net/10962/d1015724
- Description: Amitraz is a formamide acaricide used predominantly in the control of ectoparasites in livestock and honeybees. Amitraz hydrolysis is rapid and occurs under acidic conditions, exposure to sunlight and biodegradation by microorganisms. The main hydrolysis product of amitraz, 2,4-dimethylaniline, is recalcitrant in the environment and toxic to humans. An electrochemical method for the determination of total amitraz residues and its final breakdown product, 2,4-dimethylaniline, in spent cattle dip, is presented. Cyclic voltammetry at a glassy carbon electrode showed the irreversible oxidation of amitraz and 2,4-dimethylaniline. A limit of detection in the range of 8.5 x 10⁻⁸ M for amitraz and 2 x 10⁻⁸ M for 2,4-dimethylaniline was determined using differential pulse voltammetry. Feasibility studies in which the effect of supporting electrolyte type and pH had on electroanalysis of amitraz and its degradants, showed that pH affects current response as well as the potential at which amitraz and its degradants are oxidised. Britton-Robinson buffer was found to be the most suitable supporting electrolyte for detection of amitraz and its degradants in terms of sensitivity and reproducibility. Studies performed using environmental samples showed that the sensitivity and reproducibility of amitraz and 2,4-dimethylaniline analyses in spent cattle dip were comparable to analyses of amitraz and 2,4-dimethylaniline performed in Britton-Robinson buffer. In addition, the feasibility qf measuring amitraz and 2,4-dimethylaniline in environmental samples was assessed and compared to amitraz and 2,4-dimethylaniline analyses in Britton-Robinson buffer. Amitraz and 2,4-dimethylaniline were readily detectable in milk and honey. Furthermore, it was elucidated that 2,4-dimethylaniline can be metabolised to 3-methylcatechol by Pseudomonas species and the proposed breakdown pathway is presented. The biological degradation of amitraz and subsequent formation of 2,4-dimethylaniline was readily monitored in spent cattle dip. The breakdown of amitraz to 2,4-dimethylaniline and then to 3-MC was monitored using cyclic voltammetry.
- Full Text:
- Date Issued: 2006
Teacher education for Mathematical Literacy: a modelling approach
- Brown, Bruce J L, Schäfer, Marc
- Authors: Brown, Bruce J L , Schäfer, Marc
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141040 , vital:37939 , DOI: 10.4102/pythagoras.v0i64.98
- Description: This paper reports on a study of the extent to which question design affects the solution strategies adopted by children when solving linear number pattern generalisation tasks presented in pictorial and numeric contexts. The research tool comprised a series of 22 pencil-and-paper exercises based on linear generalisation tasks set in both numeric and two-dimensional pictorial contexts. The responses to these linear generalisation questions were classified by means of stage descriptors as well as stage modifiers. The method or strategy adopted was analysed and classified into one of seven categories. In addition, a meta-analysis focused on the formula derived for the nth term in conjunction with its justification. The results of this study strongly support the notion that question design can play a critical role in influencing learners' choice of strategy and level of attainment when solving pattern generalisation tasks. An understanding of the importance of appropriate question design has direct pedagogical application within the context of the mathematics classroom.
- Full Text:
- Date Issued: 2006
- Authors: Brown, Bruce J L , Schäfer, Marc
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141040 , vital:37939 , DOI: 10.4102/pythagoras.v0i64.98
- Description: This paper reports on a study of the extent to which question design affects the solution strategies adopted by children when solving linear number pattern generalisation tasks presented in pictorial and numeric contexts. The research tool comprised a series of 22 pencil-and-paper exercises based on linear generalisation tasks set in both numeric and two-dimensional pictorial contexts. The responses to these linear generalisation questions were classified by means of stage descriptors as well as stage modifiers. The method or strategy adopted was analysed and classified into one of seven categories. In addition, a meta-analysis focused on the formula derived for the nth term in conjunction with its justification. The results of this study strongly support the notion that question design can play a critical role in influencing learners' choice of strategy and level of attainment when solving pattern generalisation tasks. An understanding of the importance of appropriate question design has direct pedagogical application within the context of the mathematics classroom.
- Full Text:
- Date Issued: 2006
"Museum spaces in post-apartheid South Africa": the Durban Art Gallery as a case study
- Authors: Brown, Carol
- Date: 2006
- Subjects: Durban Art Gallery -- History Museums -- South Africa -- Durban Art museums -- South Africa -- Durban Art -- South Africa -- Durban -- Exhibitions Art, Modern -- 20th century -- Exhibitions Art, Modern -- 19th century -- Exhibitions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2446 , http://hdl.handle.net/10962/d1006231
- Description: This dissertation examines the history of the Durban Art Gallery from its founding in 1892 until 2004, a decade after the First Democratic Election. While the emphasis is on significant changes that were introduced in the post-1994 period, the earlier section of the study locates these initiatives within a broad historical framework. The collecting policies of the museum as well as its exhibitions and programmes are considered in the light of the institution 's changing social and political context as well as shifting imperatives within a local, regional and national art world. The Durban Art Gallery was established in order to promote a European, and particularly British, culture, and the acquisition and appreciation of art was considered an important element in the formation of a stable society. By providing a broad overview of the early years of the gallery, I identify reasons for the choice of acquisitions and explore the impact and reception of a selection of exhibitions. I investigate changes during the 1960s and 1970s through an examination of the Art South Africa Today exhibitions: in addition to opening up institutional spaces to a racially mixed community, these exhibitions marked the beginning of an imperative to show protest art. I argue that, during the political climate of the 1980s, there was a tension in the cultural arena between, on the one hand, a motivation to retain a Western ideal of 'high art' and, on the other, a drive to accommodate the new forms of people's art and to challenge the values and ideological standpoints that had been instrumental in shaping collecting and exhibiting policies in the South African art arena. I explore this tension through a discussion of the Cape Town Triennial exhibitions, organised jointly by all the official museums, which ran alongside more inclusive and independently curated exhibitions, such as Tributaries, which were shown mainly outside the country. The post-1994 period marked an opening up of spaces, both literally and conceptually. This openness was manifest in the revised strategies that were introduced to show the Durban Art Gallery 's permanent collection as well as in two key public projects that were started - Red Eye @rt and the AIDS 2000 ribbon. Through an examination of these strategies and initiatives, I argue that the central role of the Durban Art Gallery has shifted from being a repository to providing an interactive public space.
- Full Text:
- Date Issued: 2006
- Authors: Brown, Carol
- Date: 2006
- Subjects: Durban Art Gallery -- History Museums -- South Africa -- Durban Art museums -- South Africa -- Durban Art -- South Africa -- Durban -- Exhibitions Art, Modern -- 20th century -- Exhibitions Art, Modern -- 19th century -- Exhibitions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2446 , http://hdl.handle.net/10962/d1006231
- Description: This dissertation examines the history of the Durban Art Gallery from its founding in 1892 until 2004, a decade after the First Democratic Election. While the emphasis is on significant changes that were introduced in the post-1994 period, the earlier section of the study locates these initiatives within a broad historical framework. The collecting policies of the museum as well as its exhibitions and programmes are considered in the light of the institution 's changing social and political context as well as shifting imperatives within a local, regional and national art world. The Durban Art Gallery was established in order to promote a European, and particularly British, culture, and the acquisition and appreciation of art was considered an important element in the formation of a stable society. By providing a broad overview of the early years of the gallery, I identify reasons for the choice of acquisitions and explore the impact and reception of a selection of exhibitions. I investigate changes during the 1960s and 1970s through an examination of the Art South Africa Today exhibitions: in addition to opening up institutional spaces to a racially mixed community, these exhibitions marked the beginning of an imperative to show protest art. I argue that, during the political climate of the 1980s, there was a tension in the cultural arena between, on the one hand, a motivation to retain a Western ideal of 'high art' and, on the other, a drive to accommodate the new forms of people's art and to challenge the values and ideological standpoints that had been instrumental in shaping collecting and exhibiting policies in the South African art arena. I explore this tension through a discussion of the Cape Town Triennial exhibitions, organised jointly by all the official museums, which ran alongside more inclusive and independently curated exhibitions, such as Tributaries, which were shown mainly outside the country. The post-1994 period marked an opening up of spaces, both literally and conceptually. This openness was manifest in the revised strategies that were introduced to show the Durban Art Gallery 's permanent collection as well as in two key public projects that were started - Red Eye @rt and the AIDS 2000 ribbon. Through an examination of these strategies and initiatives, I argue that the central role of the Durban Art Gallery has shifted from being a repository to providing an interactive public space.
- Full Text:
- Date Issued: 2006
Reactions in the solid state
- Authors: Brown, Michael Ewart
- Date: 2006
- Subjects: Solid state chemistry , Thermal analysis , Chemistry, Analytic
- Language: English
- Type: Thesis , Doctoral , DSc
- Identifier: vital:4529 , http://hdl.handle.net/10962/d1015762
- Description: I have chosen the title for this thesis, "Reactions in the Solid State", for two reasons: Firstly, it is broad enough to cover all of my areas of research, which have been: • Effects of irradiation on solids (PhD topic) • Silver refining (while at the Chamber of Mines) • Kinetics of decomposition of solids (with Dr A.K. Galwey and various others) • Techniques of thermal analysis • Pyrotechnic delay systems (with support from AECI Explosives) • Thermal and photostability of drugs (with Prof B.D. Glass) and, secondly, it was the title of the very successful book co-authored by Drs Andrew Galwey, David Dollimore and me. A large part of my research has been involved in the writing and editing of books, so these are covered in a separate commentary, while commentary on the more than 100 papers to which I have contributed forms the main part of this compilation. It is hoped that the electronic format will enable ready access of to all aspects of my research, including electronic versions of the original papers. The reader will need a copy of Adobe Acrobat Reader to access these.
- Full Text:
- Date Issued: 2006
- Authors: Brown, Michael Ewart
- Date: 2006
- Subjects: Solid state chemistry , Thermal analysis , Chemistry, Analytic
- Language: English
- Type: Thesis , Doctoral , DSc
- Identifier: vital:4529 , http://hdl.handle.net/10962/d1015762
- Description: I have chosen the title for this thesis, "Reactions in the Solid State", for two reasons: Firstly, it is broad enough to cover all of my areas of research, which have been: • Effects of irradiation on solids (PhD topic) • Silver refining (while at the Chamber of Mines) • Kinetics of decomposition of solids (with Dr A.K. Galwey and various others) • Techniques of thermal analysis • Pyrotechnic delay systems (with support from AECI Explosives) • Thermal and photostability of drugs (with Prof B.D. Glass) and, secondly, it was the title of the very successful book co-authored by Drs Andrew Galwey, David Dollimore and me. A large part of my research has been involved in the writing and editing of books, so these are covered in a separate commentary, while commentary on the more than 100 papers to which I have contributed forms the main part of this compilation. It is hoped that the electronic format will enable ready access of to all aspects of my research, including electronic versions of the original papers. The reader will need a copy of Adobe Acrobat Reader to access these.
- Full Text:
- Date Issued: 2006
A structural study of Witteberg group rocks (Cape supergroup) in the Cape fold belt, Steytlerville district, Eastern Cape
- Authors: Brunsdon, Gideon
- Date: 2006
- Subjects: Geology, Structural|zSouth Africa|zEastern Cape , Faults (Geology)|zSouth Africa|zEastern Cape , Folds (Geology)|zSouth Africa|zEastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10666 , http://hdl.handle.net/10948/d1019682
- Description: A structural study of Witteberg Group Rocks was conducted along the Soutkloof River, approximately 14 km east of Steytlerville, Eastern Cape Province of South Africa. Here a north to south geotraverse was studied in an attempt at unravelling the structural geology of the rocks belonging to the Upper Devonian to Lower Carboniferous Witteberg Group (Upper Cape Supergroup). These rocks are mostly arenaceous and include quartzite, sandstone, siltstone and shale which have been folded, faulted and metamorphosed. Thrust, normal and strike-slip faulting occur in the area. Shallow south-dipping low-angle thrust fault planes are displaced by steep south-dipping thrust planes and subordinate north-dipping backthrusts. Displacement along thrust planes is predominantly northwards. Steeply dipping thrust fault planes are often reactivated as east-west striking normal faults. Strike-slip faulting postdates all observed structural features and displaces normal and thrust fault planes. Open to tight folds are present and are mostly northvergent and often steepened or truncated by steep south-dipping thrust fault planes. South-vergent folds are related to backthrusting and post-fold faulting. The study has revealed that the current geological map and the local stratigraphy were compiled without recognising major structural features such as thrust, normal and strike-slip faulting and their (the map and currently accepted stratigraphy) validity are therefore questioned. The presence of extensive faulting suggests that the conventional stratigraphic interpretation of the Witteberg Group should be revised.
- Full Text:
- Date Issued: 2006
- Authors: Brunsdon, Gideon
- Date: 2006
- Subjects: Geology, Structural|zSouth Africa|zEastern Cape , Faults (Geology)|zSouth Africa|zEastern Cape , Folds (Geology)|zSouth Africa|zEastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10666 , http://hdl.handle.net/10948/d1019682
- Description: A structural study of Witteberg Group Rocks was conducted along the Soutkloof River, approximately 14 km east of Steytlerville, Eastern Cape Province of South Africa. Here a north to south geotraverse was studied in an attempt at unravelling the structural geology of the rocks belonging to the Upper Devonian to Lower Carboniferous Witteberg Group (Upper Cape Supergroup). These rocks are mostly arenaceous and include quartzite, sandstone, siltstone and shale which have been folded, faulted and metamorphosed. Thrust, normal and strike-slip faulting occur in the area. Shallow south-dipping low-angle thrust fault planes are displaced by steep south-dipping thrust planes and subordinate north-dipping backthrusts. Displacement along thrust planes is predominantly northwards. Steeply dipping thrust fault planes are often reactivated as east-west striking normal faults. Strike-slip faulting postdates all observed structural features and displaces normal and thrust fault planes. Open to tight folds are present and are mostly northvergent and often steepened or truncated by steep south-dipping thrust fault planes. South-vergent folds are related to backthrusting and post-fold faulting. The study has revealed that the current geological map and the local stratigraphy were compiled without recognising major structural features such as thrust, normal and strike-slip faulting and their (the map and currently accepted stratigraphy) validity are therefore questioned. The presence of extensive faulting suggests that the conventional stratigraphic interpretation of the Witteberg Group should be revised.
- Full Text:
- Date Issued: 2006
Evaluation of Bacillus thuringiensis Berliner as an alternative control of small hive beetles, Aethina tumida Murray (Coleoptera: Nitidulidae)
- Buchholz, S, Neumann, Peter, Neumann, K, Hepburn, H Randall
- Authors: Buchholz, S , Neumann, Peter , Neumann, K , Hepburn, H Randall
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6929 , http://hdl.handle.net/10962/d1011945
- Description: Small hive beetles, Aethina tumida Murray, are parasites and scavengers of honeybee colonies, Apis mellifera L., and have become an invasive species that can cause considerable damage in its new distribution areas. An effective subspecies of Bacillus thuringiensis Berliner (=Bt) would provide an alternative to chemical control of this pest. Therefore, we tested three different Bt strains [B. thuringiensis, var. aizawai (B401®), B. thuringiensis var. kurstaki (Novodor®) and B. thuringiensis var. San Diego tenebrionis (Jackpot®)] and Perizin® (3.2% coumaphos), each applied on combs with a pollen diet fed to pairs of adult beetles. This evaluates the products for the suppression of successful small hive beetle reproduction. While none of the tested Bt strains showed a significant effect on the number of produced wandering larvae, we could confirm the efficacy of coumaphos for the control of small hive beetles. We further show that it is also efficient when applied with a lower concentration as a liquid on the combs. We suggest the continued search for efficient Bt strains naturally infesting small hive beetles in its endemic and new ranges, which may become a part of the integrated management of this pest.
- Full Text:
- Date Issued: 2006
- Authors: Buchholz, S , Neumann, Peter , Neumann, K , Hepburn, H Randall
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6929 , http://hdl.handle.net/10962/d1011945
- Description: Small hive beetles, Aethina tumida Murray, are parasites and scavengers of honeybee colonies, Apis mellifera L., and have become an invasive species that can cause considerable damage in its new distribution areas. An effective subspecies of Bacillus thuringiensis Berliner (=Bt) would provide an alternative to chemical control of this pest. Therefore, we tested three different Bt strains [B. thuringiensis, var. aizawai (B401®), B. thuringiensis var. kurstaki (Novodor®) and B. thuringiensis var. San Diego tenebrionis (Jackpot®)] and Perizin® (3.2% coumaphos), each applied on combs with a pollen diet fed to pairs of adult beetles. This evaluates the products for the suppression of successful small hive beetle reproduction. While none of the tested Bt strains showed a significant effect on the number of produced wandering larvae, we could confirm the efficacy of coumaphos for the control of small hive beetles. We further show that it is also efficient when applied with a lower concentration as a liquid on the combs. We suggest the continued search for efficient Bt strains naturally infesting small hive beetles in its endemic and new ranges, which may become a part of the integrated management of this pest.
- Full Text:
- Date Issued: 2006
Understanding educator-mediated conflict resolution in a preschool environment: the experiences and feelings of preschool educators
- Authors: Cakwe, Mandisa
- Date: 2006
- Subjects: Education, Preschool , Early childhood education , Preschool children , Conflict management
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2943 , http://hdl.handle.net/10962/d1002452 , Education, Preschool , Early childhood education , Preschool children , Conflict management
- Description: This thesis discusses the experiences and feelings of preschool educators when resolving situations of conflict between preschool children. Data was collected by means of semistructured individual interviews with preschool educators and a video recorder recording conflict situations among preschool children focusing on educator resolution strategies. Grounded theory was used as a data analysis technique to analyse the data collected. The analysis revealed that the preschool educators under study do not use mediation as a conflict resolution strategy but use various strategies that include, prevention, directive approach, arbitration, myths and threats and rules. Data analysis also revealed that these preschool educators encounter experiences and feelings before, while and after intervening in the conflict situations of children. These findings imply that preschool educators lack the professional skill of conflict resolution. This suggests an urgent need of restructuring of the preschool educator’s training to include conflict resolution training as one of their important component. Educators and parents also need to be consulted or involved in the process of restructuring the training.
- Full Text:
- Date Issued: 2006
- Authors: Cakwe, Mandisa
- Date: 2006
- Subjects: Education, Preschool , Early childhood education , Preschool children , Conflict management
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2943 , http://hdl.handle.net/10962/d1002452 , Education, Preschool , Early childhood education , Preschool children , Conflict management
- Description: This thesis discusses the experiences and feelings of preschool educators when resolving situations of conflict between preschool children. Data was collected by means of semistructured individual interviews with preschool educators and a video recorder recording conflict situations among preschool children focusing on educator resolution strategies. Grounded theory was used as a data analysis technique to analyse the data collected. The analysis revealed that the preschool educators under study do not use mediation as a conflict resolution strategy but use various strategies that include, prevention, directive approach, arbitration, myths and threats and rules. Data analysis also revealed that these preschool educators encounter experiences and feelings before, while and after intervening in the conflict situations of children. These findings imply that preschool educators lack the professional skill of conflict resolution. This suggests an urgent need of restructuring of the preschool educator’s training to include conflict resolution training as one of their important component. Educators and parents also need to be consulted or involved in the process of restructuring the training.
- Full Text:
- Date Issued: 2006
In search of optimal stocking regimes in semi-arid grazing lands : one size does not fit all
- Campbell, Bruce M, Gordon, Iain J, Luckert, Martin K, Petheram, Lisa, Vetter, Susan M
- Authors: Campbell, Bruce M , Gordon, Iain J , Luckert, Martin K , Petheram, Lisa , Vetter, Susan M
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6507 , http://hdl.handle.net/10962/d1005934
- Description: We discuss the search for optimal stocking regimes in semi-arid grazing lands. We argue that ‘one size does not fit all’ and that different stocking regimes are appropriate under different conditions. This paper is an attempt to move beyond polarization of the current debate towards a more integrative and flexible approach to grazing management. We propose five different conditions as major influences on grazing regimes: environmental variability and predictability; degradation and thresholds; property right regimes; discount rates; and market stability and prices. We suggest a lack of connection between the micro-economics literature and natural science and social-anthropological literature. It is timely to achieve greater integration around some key questions and hypotheses, and recognize that policy prescriptions at national or even regional levels are likely to have limited value due to context specificity.
- Full Text:
- Date Issued: 2006
- Authors: Campbell, Bruce M , Gordon, Iain J , Luckert, Martin K , Petheram, Lisa , Vetter, Susan M
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6507 , http://hdl.handle.net/10962/d1005934
- Description: We discuss the search for optimal stocking regimes in semi-arid grazing lands. We argue that ‘one size does not fit all’ and that different stocking regimes are appropriate under different conditions. This paper is an attempt to move beyond polarization of the current debate towards a more integrative and flexible approach to grazing management. We propose five different conditions as major influences on grazing regimes: environmental variability and predictability; degradation and thresholds; property right regimes; discount rates; and market stability and prices. We suggest a lack of connection between the micro-economics literature and natural science and social-anthropological literature. It is timely to achieve greater integration around some key questions and hypotheses, and recognize that policy prescriptions at national or even regional levels are likely to have limited value due to context specificity.
- Full Text:
- Date Issued: 2006