Assessing the value of public investment into biological control research for invasive alien plants : the ARC PPRI Weeds Research Division
- Authors: Scarr, Lowell Martin
- Date: 2016
- Subjects: Alien plants -- Biological control , Invasive plants -- Biological control , Alien plants -- Economic aspects , Invasive plants -- Economic aspects , Weeds -- Biological control
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1126 , http://hdl.handle.net/10962/d1020604
- Description: This study investigates the economic impact of the ARC PPRI Weeds Research Division. The Division researches appropriate methods of biological control for invasive alien plants (IAPs). These plants pose an increasing threat to environmental integrity and ecosystem service provision impacting on economic potential. Since the work of the Division is considered a public good, a predominantly descriptive approach has been adopted for the valuation process. A combination of quantitative cost analysis and a qualitative study of the impacts of research and invasive alien plants is used to deal with the challenges associated with non-market valuation. The study found that investment into the Weeds Division is a valuable activity that supports the long-term growth potential of the South African economy. The role of a well-functioning environment is highlighted as an essential base for the creation of sustained growth opportunities in any society. It was determined that investment into the Division should be increased into the future to support efficient spending of scarce state funds. Biological control research was found to provide strategic future growth potential, creating opportunities for the development of a competitive advantage in the biotechnology and environmental management sectors. The study adds to the increasing move towards a more holistic view of economic valuation, taking factors other than pure finance and econometrics into consideration. This is an important shift in prevailing economic thought, as a realisation is reached that a single, or even triple, bottom line is an outdated and insufficient decision making basis.
- Full Text:
- Authors: Scarr, Lowell Martin
- Date: 2016
- Subjects: Alien plants -- Biological control , Invasive plants -- Biological control , Alien plants -- Economic aspects , Invasive plants -- Economic aspects , Weeds -- Biological control
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1126 , http://hdl.handle.net/10962/d1020604
- Description: This study investigates the economic impact of the ARC PPRI Weeds Research Division. The Division researches appropriate methods of biological control for invasive alien plants (IAPs). These plants pose an increasing threat to environmental integrity and ecosystem service provision impacting on economic potential. Since the work of the Division is considered a public good, a predominantly descriptive approach has been adopted for the valuation process. A combination of quantitative cost analysis and a qualitative study of the impacts of research and invasive alien plants is used to deal with the challenges associated with non-market valuation. The study found that investment into the Weeds Division is a valuable activity that supports the long-term growth potential of the South African economy. The role of a well-functioning environment is highlighted as an essential base for the creation of sustained growth opportunities in any society. It was determined that investment into the Division should be increased into the future to support efficient spending of scarce state funds. Biological control research was found to provide strategic future growth potential, creating opportunities for the development of a competitive advantage in the biotechnology and environmental management sectors. The study adds to the increasing move towards a more holistic view of economic valuation, taking factors other than pure finance and econometrics into consideration. This is an important shift in prevailing economic thought, as a realisation is reached that a single, or even triple, bottom line is an outdated and insufficient decision making basis.
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Exploring perceptions on aesthetics and emotional labour experienced by women working in two different clothing retail shops in Port Elizabeth and Grahamstown
- Authors: Dalikeni, Tawonga
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/3750 , vital:20541
- Description: The retail industry is the fastest growing sector in the economy contributing trillions towards the global revenue. In a post-apartheid South African economy that is experiencing increased buying power, the clothing retail sector to be specific is consequently flourishing. However, the economy is faced by structural adjustments; an accompanying concern is how foreign direct investments and pressures of globalization impact the operation of clothing retail shops. The main focus of this thesis based on the qualitative research methodology is emotional and aesthetic labour being experienced by women working in two clothing retail shops in Port Elizabeth and Grahamstown. Empirical data shows that emotional labour is a dominant form of labour in the clothing retail shops under investigation. The women working as sales assistants are trained to exude a certain emotional aura when dealing with customers to build a relationship that will encourage the customer to purchase from the shop. Aesthetic labour on the other hand is an important public relations strategy used as sales assistants dress in a way that represents their company brand. Edgars employees dress elegantly because they focus more on formal dressing whilst Mr Price employees dress more casually because they focus on casual and relaxed fashion. Besides these external attributes, the study showed that certain aspects of the job are fairly similar. With codes of happiness and strings of dissatisfaction towards their job requirements, the women’s social lives suffer the atrocities of their long working hours and limited off-duty days.
- Full Text:
- Authors: Dalikeni, Tawonga
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/3750 , vital:20541
- Description: The retail industry is the fastest growing sector in the economy contributing trillions towards the global revenue. In a post-apartheid South African economy that is experiencing increased buying power, the clothing retail sector to be specific is consequently flourishing. However, the economy is faced by structural adjustments; an accompanying concern is how foreign direct investments and pressures of globalization impact the operation of clothing retail shops. The main focus of this thesis based on the qualitative research methodology is emotional and aesthetic labour being experienced by women working in two clothing retail shops in Port Elizabeth and Grahamstown. Empirical data shows that emotional labour is a dominant form of labour in the clothing retail shops under investigation. The women working as sales assistants are trained to exude a certain emotional aura when dealing with customers to build a relationship that will encourage the customer to purchase from the shop. Aesthetic labour on the other hand is an important public relations strategy used as sales assistants dress in a way that represents their company brand. Edgars employees dress elegantly because they focus more on formal dressing whilst Mr Price employees dress more casually because they focus on casual and relaxed fashion. Besides these external attributes, the study showed that certain aspects of the job are fairly similar. With codes of happiness and strings of dissatisfaction towards their job requirements, the women’s social lives suffer the atrocities of their long working hours and limited off-duty days.
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The interface between nurse and patient in health care: exploring the use of emotional labour among nurses in Mthatha
- Authors: Maqabuka, Qawekzi
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/1477 , vital:20061
- Description: In exploring the use of emotional labour among nurses within the nurse/patient relationship, this study employed the conceptual framework of ‘emotional labour’ associated with Arlie Hochschild-as a means of examining the “nature” of the nurse patient interface, including the dynamics, challenges and intricacies that shape this relationship of care. The portrayal of emotional care offered to patients dealing with suffering and illness by nurses as an entirely natural activity for women is related to the devaluation of emotional labour. The focus of this study is how nurses manage their emotional involvement with patients to provide quality services. The study was conducted in Mthatha in the former Transkei in the Eastern Cape Province with nurses who worked St Mary’s Life Group and the Nelson Mandela Academic Hospital. A qualitative research design and qualitative ethnographic research methodology was chosen as suitable for answering the research question. Data was collected using semi-structured interviews and a focus group, and transcribed verbatim. Data analysis included identifying consistent emotional labour themes in the responses. The study’s main findings revealed that emotional labour strategies of surface acting and deep acting were utilised as a means of meeting organisational rules established by management of the two health care institutions that were investigated. Nurses understood that only desirable traits like include friendliness, smiling and proving a calming environment for patients should be exhibited. It was revealed that nurses often used sentimental work and emotion work in performing their tasks as this made their work easier. Lastly, the research revealed that external factors like overcrowding and shortages in personnel, accompanied by the emotional demands on nurses’ work has adverse effect on nurses work environment. The dissertation has contributed to the limited body of knowledge about emotional labour in the South African context and the lived experiences of nurses deploying their labour to patients.
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- Authors: Maqabuka, Qawekzi
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/1477 , vital:20061
- Description: In exploring the use of emotional labour among nurses within the nurse/patient relationship, this study employed the conceptual framework of ‘emotional labour’ associated with Arlie Hochschild-as a means of examining the “nature” of the nurse patient interface, including the dynamics, challenges and intricacies that shape this relationship of care. The portrayal of emotional care offered to patients dealing with suffering and illness by nurses as an entirely natural activity for women is related to the devaluation of emotional labour. The focus of this study is how nurses manage their emotional involvement with patients to provide quality services. The study was conducted in Mthatha in the former Transkei in the Eastern Cape Province with nurses who worked St Mary’s Life Group and the Nelson Mandela Academic Hospital. A qualitative research design and qualitative ethnographic research methodology was chosen as suitable for answering the research question. Data was collected using semi-structured interviews and a focus group, and transcribed verbatim. Data analysis included identifying consistent emotional labour themes in the responses. The study’s main findings revealed that emotional labour strategies of surface acting and deep acting were utilised as a means of meeting organisational rules established by management of the two health care institutions that were investigated. Nurses understood that only desirable traits like include friendliness, smiling and proving a calming environment for patients should be exhibited. It was revealed that nurses often used sentimental work and emotion work in performing their tasks as this made their work easier. Lastly, the research revealed that external factors like overcrowding and shortages in personnel, accompanied by the emotional demands on nurses’ work has adverse effect on nurses work environment. The dissertation has contributed to the limited body of knowledge about emotional labour in the South African context and the lived experiences of nurses deploying their labour to patients.
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Using a classroom library to promote extensive reading in a Grade 8 class in a Fort Beaufort District School, Eastern Cape : an action research case study.
- Authors: Bushula, Bruce Simphiwe
- Date: 2015
- Subjects: Classroom libraries -- South africa -- Eastern Cape -- Case studies , Reading (Secondary) , Literacy -- Study and teaching (Secondary) , Literacy programs
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2022 , http://hdl.handle.net/10962/d1017333
- Description: This thesis reports on a collaborative action research case study with Grade 8 learners in a rural high school in Fort Beaufort District, Eastern Cape, South Africa. The goals of the case study were firstly, to understand best practices for promoting extensive reading using a classroom library, and secondly, to use these insights to put an extensive reading programme in place with a view to improving my practice as a language teacher and to gain better understanding of ways of enhancing my Grade 8 learners’ literacy skills. The following qualitative methods were used to collect data: observation, semi-structured interviews, class discussion, questionnaires, journal reflections and document analysis. Analysis of data involved identification of emerging themes and patterns. The findings suggest that the strategies used in the extensive reading intervention improved my learners’ levels of engagement with reading. Putting these strategies into practice, and reflecting critically on how to refine them helped enrich my own professional insight and development in relation to the implementation of extensive reading programmes. Since action research is usually designed in spirals of action, this research serves as a first spiral and a foundation upon which to build second and subsequent spirals (which do not form part of this research). The study highlighted the fact that certain challenges that emerged (for example, shortage of books at the learners’ level, and a lack of parental cooperation) need to be addressed in a second spiral of intervention. The study further suggested that the implementation of effective extensive reading programmes by teachers in the middle and upper phases of secondary schooling requires further investigation.
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- Authors: Bushula, Bruce Simphiwe
- Date: 2015
- Subjects: Classroom libraries -- South africa -- Eastern Cape -- Case studies , Reading (Secondary) , Literacy -- Study and teaching (Secondary) , Literacy programs
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2022 , http://hdl.handle.net/10962/d1017333
- Description: This thesis reports on a collaborative action research case study with Grade 8 learners in a rural high school in Fort Beaufort District, Eastern Cape, South Africa. The goals of the case study were firstly, to understand best practices for promoting extensive reading using a classroom library, and secondly, to use these insights to put an extensive reading programme in place with a view to improving my practice as a language teacher and to gain better understanding of ways of enhancing my Grade 8 learners’ literacy skills. The following qualitative methods were used to collect data: observation, semi-structured interviews, class discussion, questionnaires, journal reflections and document analysis. Analysis of data involved identification of emerging themes and patterns. The findings suggest that the strategies used in the extensive reading intervention improved my learners’ levels of engagement with reading. Putting these strategies into practice, and reflecting critically on how to refine them helped enrich my own professional insight and development in relation to the implementation of extensive reading programmes. Since action research is usually designed in spirals of action, this research serves as a first spiral and a foundation upon which to build second and subsequent spirals (which do not form part of this research). The study highlighted the fact that certain challenges that emerged (for example, shortage of books at the learners’ level, and a lack of parental cooperation) need to be addressed in a second spiral of intervention. The study further suggested that the implementation of effective extensive reading programmes by teachers in the middle and upper phases of secondary schooling requires further investigation.
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An analysis of the impact of an official diagnosis and label of ʹdyslexiaʹ on pupils’ self-concept and self-esteem : a sociological case study involving pupils in Grahamstown
- Authors: Johnson, Gwendolyn Gay
- Date: 2014
- Subjects: Dyslexic children -- Education -- South Africa -- Grahamstown -- Case studies , Dyslexic children -- South Africa -- Grahamstown -- Psychological aspects -- Case studies , Dyslexic children -- Social aspects -- South Africa -- Grahamstown -- Case studies , Self-perception in adolescence , Emotions in adolescence , Dyslexia , Education, Secondary -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3375 , http://hdl.handle.net/10962/d1013124
- Description: The aim of this study is to develop an understanding of how Grahamstown teenagers are affected by the label ʹdyslexiaʹ; by providing a space in which their feelings about being labelled dyslexic and their experiences can be voiced. Historically much international and local research has focussed on causation and remediation of dyslexia and has neglected the social aspects of the diagnosis. Causation and remediation are categories which form part of the medical or educational models. A social model of dyslexia needs to be applied. Due to the paucity of South African literature on the social experiences of dyslexic teenagers, this research thesis aims to add to the body of knowledge and hopefully provide an avenue for more research within the context of Sociology. This is a micro study, situated in Grahamstown Eastern Cape, South Africa, and the author recognizes that responses cannot be generalized to the greater dyslexic population. All human environments consist of objects which are given meaning through social interaction. Meaning is central to human behaviour and therefor explains the ways in which humans conduct their lives based on these meanings. For this reason George Herbert Mead’s (1934) and Herbert Blumers (1969) symbolic interactionist positions have framed the theoretical approach to this research. Qualitative methods of interviewing provide an opportunity for dyslexic individuals to discuss the meaning dyslexia gives to them, from their perspective and in their own words. The following conclusions have been arrived at: Educational psychologists in Grahamstown are reticent to diagnose individuals as dyslexic. This lack of identification hinders early intervention which can be very detrimental to individuals struggling with reading, writing and spelling as well as the associated co-morbid conditions of dyslexia. Teenagers who have had early diagnosis and intervention with support structures in place identify with their dyslexic identity more positively as they are able to make sense of their struggles of a dyslexic nature.
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- Authors: Johnson, Gwendolyn Gay
- Date: 2014
- Subjects: Dyslexic children -- Education -- South Africa -- Grahamstown -- Case studies , Dyslexic children -- South Africa -- Grahamstown -- Psychological aspects -- Case studies , Dyslexic children -- Social aspects -- South Africa -- Grahamstown -- Case studies , Self-perception in adolescence , Emotions in adolescence , Dyslexia , Education, Secondary -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3375 , http://hdl.handle.net/10962/d1013124
- Description: The aim of this study is to develop an understanding of how Grahamstown teenagers are affected by the label ʹdyslexiaʹ; by providing a space in which their feelings about being labelled dyslexic and their experiences can be voiced. Historically much international and local research has focussed on causation and remediation of dyslexia and has neglected the social aspects of the diagnosis. Causation and remediation are categories which form part of the medical or educational models. A social model of dyslexia needs to be applied. Due to the paucity of South African literature on the social experiences of dyslexic teenagers, this research thesis aims to add to the body of knowledge and hopefully provide an avenue for more research within the context of Sociology. This is a micro study, situated in Grahamstown Eastern Cape, South Africa, and the author recognizes that responses cannot be generalized to the greater dyslexic population. All human environments consist of objects which are given meaning through social interaction. Meaning is central to human behaviour and therefor explains the ways in which humans conduct their lives based on these meanings. For this reason George Herbert Mead’s (1934) and Herbert Blumers (1969) symbolic interactionist positions have framed the theoretical approach to this research. Qualitative methods of interviewing provide an opportunity for dyslexic individuals to discuss the meaning dyslexia gives to them, from their perspective and in their own words. The following conclusions have been arrived at: Educational psychologists in Grahamstown are reticent to diagnose individuals as dyslexic. This lack of identification hinders early intervention which can be very detrimental to individuals struggling with reading, writing and spelling as well as the associated co-morbid conditions of dyslexia. Teenagers who have had early diagnosis and intervention with support structures in place identify with their dyslexic identity more positively as they are able to make sense of their struggles of a dyslexic nature.
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How community participation and stakeholder involvement can improve recycling : an investigation of initiatives and opportunities in Simunye
- Authors: Myeni, Jabu R
- Date: 2013
- Subjects: Recycling (Waste, etc.) -- Swaziland Refuse and refuse disposal -- Swaziland -- Citizen participation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:803 , http://hdl.handle.net/10962/d1006457
- Description: This report presents the findings of a research project whereby the initiatives and opportunities for municipal solid waste (MSW) recycling were investigated in the town of Simunye, in Swaziland with a view to establish how recycling, in particular household waste recycling, can be improved through stakeholder involvement and community participation during the planning and implementation of a sustainable system for household waste recycling in Simunye. The reason for focusing on household waste was because source separation of household waste was identified as a potential area for improving efficiencies and cutting costs by the local authority. It was deemed necessary to conduct research because there was a history of failure in respect of household recycling. In 2006 an initiative, by the local authority, for separating household waste at source had ended up in failure. The participation rates of the households turned out to be very low even though they had been issued, free of charge, some plastic bags for sorting the waste. Some of the households were found using the bags for other purposes rather than recycling. As a result, the initiative had to be suspended (White, 2010). There is a new move to revive the project in order to cut costs and minimize wastages. This time around the local authority is determined for the new project to be a success story. Since the underlying causes for the failure of the previous initiative were never investigated formally (Khumalo, 2010), the starting point would be to identify and try to eliminate all the potential barriers to recycling through a consultative process to start with.
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- Authors: Myeni, Jabu R
- Date: 2013
- Subjects: Recycling (Waste, etc.) -- Swaziland Refuse and refuse disposal -- Swaziland -- Citizen participation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:803 , http://hdl.handle.net/10962/d1006457
- Description: This report presents the findings of a research project whereby the initiatives and opportunities for municipal solid waste (MSW) recycling were investigated in the town of Simunye, in Swaziland with a view to establish how recycling, in particular household waste recycling, can be improved through stakeholder involvement and community participation during the planning and implementation of a sustainable system for household waste recycling in Simunye. The reason for focusing on household waste was because source separation of household waste was identified as a potential area for improving efficiencies and cutting costs by the local authority. It was deemed necessary to conduct research because there was a history of failure in respect of household recycling. In 2006 an initiative, by the local authority, for separating household waste at source had ended up in failure. The participation rates of the households turned out to be very low even though they had been issued, free of charge, some plastic bags for sorting the waste. Some of the households were found using the bags for other purposes rather than recycling. As a result, the initiative had to be suspended (White, 2010). There is a new move to revive the project in order to cut costs and minimize wastages. This time around the local authority is determined for the new project to be a success story. Since the underlying causes for the failure of the previous initiative were never investigated formally (Khumalo, 2010), the starting point would be to identify and try to eliminate all the potential barriers to recycling through a consultative process to start with.
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Identification and evaluation of key factors for rehabilitation of shores denuded of mussels (Perna perna) along the Transkei Coast, South Africa
- Authors: Macala, Lukholo
- Date: 2013
- Subjects: Mussels -- Ecology -- South Africa -- Transkei , Mussels -- Conservation -- South Africa -- Transkei , Mussels -- Growth -- South Africa -- Transkei , Mussels -- Effect of human beings on -- South Africa -- Transkei , Mussels -- Reproduction -- South Africa -- Transkei , Perna -- South Africa -- Transkei
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5611 , http://hdl.handle.net/10962/d1002966 , Mussels -- Ecology -- South Africa -- Transkei , Mussels -- Conservation -- South Africa -- Transkei , Mussels -- Growth -- South Africa -- Transkei , Mussels -- Effect of human beings on -- South Africa -- Transkei , Mussels -- Reproduction -- South Africa -- Transkei , Perna -- South Africa -- Transkei
- Description: Mussels play an important supplementary role in the diet of local communities on the Transkei coast in the Eastern Cape province of South Africa. The exploitation of mussels date back to about 1350 years ago, but in the last 3 decades, exploitation of the brown mussel Perna perna has become unsustainable with mussels collected as small as 30-40mm when they are only just sexually mature. Dye and Dyantyi (2002) developed a technique to rehabilitate areas denuded of adult mussels. The government sponsored Mussel Rehabilitation Project (MRP) to use this technique but only some sites have been successfully rehabilitated, reaching c. 80 % cover within a year whilst others only reach about 5%. At an unexploited site (Riet River), I tested the effects of mussel size and wave strength on the effectiveness of the rehabilitation technique, hypothesizing that different size classes may respond differently due to differences in their energy allocation (growth vs reproduction), while wave action determines food supply. Small (1-2cm) and large mussels (3-4cm) were deployed for rehabilitation at 2 exposed and 2 sheltered sites, separated by 100s m. A similar study was repeated in Coffee Bay where shores are exploited. Six sites were selected, 3 sites that had been successfully rehabilitated and 3 that were unsuccessful according to the MRP. Again, two size classes were used but these differed from the first experiment. Mussels of 3-4cm size were now rated as small and 5-6cm as large. Two methods were used to re-attach mussels, the original and the same method with the addition of mesh bags during mussel deployment. Treatments were examined on three occasions at approximately one month intervals. At Riet River, the sites chosen did not show differences in wave strength (measured using dynamometers) or water flux (measured using erosion of cement balls) so that water motion was excluded from the analyses. Small mussels grew faster and had weaker attachment than large mussels. There was no difference in condition index between small and large mussels, or in the numbers of recruits settling among the byssus threads of deployed mussels of the two size classes. In Coffee Bay, there was no relationship between rehabilitation success and maximum wave force, and no difference in bulk water flux among sites. Small mussels deployed using mesh bags survived better than non-meshed or large mussels of either treatment. There was no difference in condition index (CI) between mesh and no-mesh, or between small and large mussels. As in the case of Riet River, small mussels grew faster than large mussels, but large mussels attached stronger than small mussels, with no effect of mesh. Although the factors that improve reseeding of mussels can be identified (use of mesh, use of small mussels, choice of sites with high recruitment rates), successful long-term rehabilitation requires appropriate subsequent management of re-seeded sites.
- Full Text:
- Authors: Macala, Lukholo
- Date: 2013
- Subjects: Mussels -- Ecology -- South Africa -- Transkei , Mussels -- Conservation -- South Africa -- Transkei , Mussels -- Growth -- South Africa -- Transkei , Mussels -- Effect of human beings on -- South Africa -- Transkei , Mussels -- Reproduction -- South Africa -- Transkei , Perna -- South Africa -- Transkei
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5611 , http://hdl.handle.net/10962/d1002966 , Mussels -- Ecology -- South Africa -- Transkei , Mussels -- Conservation -- South Africa -- Transkei , Mussels -- Growth -- South Africa -- Transkei , Mussels -- Effect of human beings on -- South Africa -- Transkei , Mussels -- Reproduction -- South Africa -- Transkei , Perna -- South Africa -- Transkei
- Description: Mussels play an important supplementary role in the diet of local communities on the Transkei coast in the Eastern Cape province of South Africa. The exploitation of mussels date back to about 1350 years ago, but in the last 3 decades, exploitation of the brown mussel Perna perna has become unsustainable with mussels collected as small as 30-40mm when they are only just sexually mature. Dye and Dyantyi (2002) developed a technique to rehabilitate areas denuded of adult mussels. The government sponsored Mussel Rehabilitation Project (MRP) to use this technique but only some sites have been successfully rehabilitated, reaching c. 80 % cover within a year whilst others only reach about 5%. At an unexploited site (Riet River), I tested the effects of mussel size and wave strength on the effectiveness of the rehabilitation technique, hypothesizing that different size classes may respond differently due to differences in their energy allocation (growth vs reproduction), while wave action determines food supply. Small (1-2cm) and large mussels (3-4cm) were deployed for rehabilitation at 2 exposed and 2 sheltered sites, separated by 100s m. A similar study was repeated in Coffee Bay where shores are exploited. Six sites were selected, 3 sites that had been successfully rehabilitated and 3 that were unsuccessful according to the MRP. Again, two size classes were used but these differed from the first experiment. Mussels of 3-4cm size were now rated as small and 5-6cm as large. Two methods were used to re-attach mussels, the original and the same method with the addition of mesh bags during mussel deployment. Treatments were examined on three occasions at approximately one month intervals. At Riet River, the sites chosen did not show differences in wave strength (measured using dynamometers) or water flux (measured using erosion of cement balls) so that water motion was excluded from the analyses. Small mussels grew faster and had weaker attachment than large mussels. There was no difference in condition index between small and large mussels, or in the numbers of recruits settling among the byssus threads of deployed mussels of the two size classes. In Coffee Bay, there was no relationship between rehabilitation success and maximum wave force, and no difference in bulk water flux among sites. Small mussels deployed using mesh bags survived better than non-meshed or large mussels of either treatment. There was no difference in condition index (CI) between mesh and no-mesh, or between small and large mussels. As in the case of Riet River, small mussels grew faster than large mussels, but large mussels attached stronger than small mussels, with no effect of mesh. Although the factors that improve reseeding of mussels can be identified (use of mesh, use of small mussels, choice of sites with high recruitment rates), successful long-term rehabilitation requires appropriate subsequent management of re-seeded sites.
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An investigation of how natural sciences teachers mediate learning of chemical reactions in Grade 9: a case study
- Authors: Xipu, Bukelwa
- Date: 2012
- Subjects: Science -- Study and teaching (Secondary) Science -- Study and teaching (Secondary) -- South Africa -- Eastern Cape Chemical reactions Science teachers -- South Africa -- Eastern Cape Science teachers -- Rating of -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1631 , http://hdl.handle.net/10962/d1003513
- Description: This research study involves two Grade 9 Natural Sciences teachers from two schools in the Lady Frere District of the Eastern Cape. The reason for selecting these two teachers is that in 2009 they, like me, obtained an Advanced Certificate in Education (Science and Maths) from Rhodes University. As a result, we have a good working relationship. Furthermore, both teachers are actively involved in the Natural Sciences curriculum in the District and their schools are not far from the District Office where I work. The principal objective of this study was to investigate how Natural Sciences teachers mediated learning in order to enhance conceptual development and understanding of chemical reactions in Grade 9. It was triggered by the transformation in curriculum in South Africa as well as by my experience of working with Natural Sciences teachers in our rural district. The study is informed by an interpretive paradigm using a qualitative case study approach. The data was gathered by administering analysis of documents, semi-structured interviews, observations, field notes and journals. During the data analysis process, patterns and themes were illuminated using the inductive analysis method. Rich data sets in relation to the main research question on how Natural Sciences teachers mediated learning in order to enhance conceptual development and understanding of chemical reactions in Grade 9 emerged from the analysed data. The conclusions that can be drawn from the study indicate that when teaching chemical reactions, teachers should have adequate content knowledge as well as pedagogical content knowledge. It is thus recommended that teachers consider the prior knowledge of learners, use a variety of teaching and learning approaches including practical activities, to make learning meaningful. The major limitation of this study is that the two selected teachers do not represent the whole population of Grade 9 teachers in the Lady Frere District. Therefore, the findings cannot be generalized to represent the larger population. It is recognised, however, that within the qualitative inquiry, reliability and generalizability play a minor role.
- Full Text:
- Authors: Xipu, Bukelwa
- Date: 2012
- Subjects: Science -- Study and teaching (Secondary) Science -- Study and teaching (Secondary) -- South Africa -- Eastern Cape Chemical reactions Science teachers -- South Africa -- Eastern Cape Science teachers -- Rating of -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1631 , http://hdl.handle.net/10962/d1003513
- Description: This research study involves two Grade 9 Natural Sciences teachers from two schools in the Lady Frere District of the Eastern Cape. The reason for selecting these two teachers is that in 2009 they, like me, obtained an Advanced Certificate in Education (Science and Maths) from Rhodes University. As a result, we have a good working relationship. Furthermore, both teachers are actively involved in the Natural Sciences curriculum in the District and their schools are not far from the District Office where I work. The principal objective of this study was to investigate how Natural Sciences teachers mediated learning in order to enhance conceptual development and understanding of chemical reactions in Grade 9. It was triggered by the transformation in curriculum in South Africa as well as by my experience of working with Natural Sciences teachers in our rural district. The study is informed by an interpretive paradigm using a qualitative case study approach. The data was gathered by administering analysis of documents, semi-structured interviews, observations, field notes and journals. During the data analysis process, patterns and themes were illuminated using the inductive analysis method. Rich data sets in relation to the main research question on how Natural Sciences teachers mediated learning in order to enhance conceptual development and understanding of chemical reactions in Grade 9 emerged from the analysed data. The conclusions that can be drawn from the study indicate that when teaching chemical reactions, teachers should have adequate content knowledge as well as pedagogical content knowledge. It is thus recommended that teachers consider the prior knowledge of learners, use a variety of teaching and learning approaches including practical activities, to make learning meaningful. The major limitation of this study is that the two selected teachers do not represent the whole population of Grade 9 teachers in the Lady Frere District. Therefore, the findings cannot be generalized to represent the larger population. It is recognised, however, that within the qualitative inquiry, reliability and generalizability play a minor role.
- Full Text:
Sample preparation for pesticide analysis in water and sediments a case study of the Okavango Delta, Botswana
- Authors: Mmualefe, Lesego Cecilia
- Date: 2010
- Subjects: Water quality -- Botswana -- Okavango Delta Water -- Analysis Pesticides -- Environmental aspects -- Botswana -- Okavango Delta Water -- Pollution -- Botswana -- Okavango Delta DDT (Insecticide) -- Environmental aspects -- Botswana -- Okavango Delta
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4344 , http://hdl.handle.net/10962/d1005006
- Description: This thesis presents a first ever extensive analysis of pesticides in water and sediments from the Okavango Delta, Botswana, employing green sample preparation techniques that require small volumes of organic solvents hence generating negligible volumes of organic solvent waste. Pesticides were extracted and pre-concentrated from water by solid phase extraction (SPE) and headspace solid phase microextraction (HS-SPME) while supercritical fluid extraction (SFE) and pressurized fluid extraction (PFE) were employed for sediments. Subsequent analysis was carried out on a gas chromatograph with electron capture detection and analytes were unequivocally confirmed by high resolution mass spectrometric detection. Hexachlorobenzene (HCB), trans-chlordane, 4,4′-DDD and 4,4′-DDE were detected after optimized HS-SPME in several water samples from the lower Delta at concentrations ranging from 2.4 to 61.4 μg L-1 that are much higher than the 0.1 μg L-1 maximum limit of individual organochlorine pesticides in drinking water set by the European Community Directive. The same samples were cleaned with ISOLUTE C18 SPE sorbent with an optimal acetone/n-hexane (1:1 v/v) mixture for the elution of analytes. No pesticides were detected after SPE clean-up and pre-concentration. HCB, aldrin and 4, 4‟-DDT were identified in sediments after SFE at concentration ranges of 1.1 - 30.3, 0.5 – 15.2 and 1.4 – 55.4 μg/g, respectively. There was an increase of pesticides concentrations in the direction of water flow from the Panhandle (point of entry) to the lower delta. DDE, fatty acids and phthalates were detected after PFE with optimized extraction solvent and temperature. The presence of DDT metabolites in the water and sediments from the Okavango Delta confirm historical exposure to the pesticide. However their cumulative concentration increase in the water-flow direction calls for further investigation of point sources for the long-term preservation of the Delta. The green sample preparation techniques and low toxicity solvents employed in this thesis are thus recommended for routine environmental monitoring exercises.
- Full Text:
- Authors: Mmualefe, Lesego Cecilia
- Date: 2010
- Subjects: Water quality -- Botswana -- Okavango Delta Water -- Analysis Pesticides -- Environmental aspects -- Botswana -- Okavango Delta Water -- Pollution -- Botswana -- Okavango Delta DDT (Insecticide) -- Environmental aspects -- Botswana -- Okavango Delta
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4344 , http://hdl.handle.net/10962/d1005006
- Description: This thesis presents a first ever extensive analysis of pesticides in water and sediments from the Okavango Delta, Botswana, employing green sample preparation techniques that require small volumes of organic solvents hence generating negligible volumes of organic solvent waste. Pesticides were extracted and pre-concentrated from water by solid phase extraction (SPE) and headspace solid phase microextraction (HS-SPME) while supercritical fluid extraction (SFE) and pressurized fluid extraction (PFE) were employed for sediments. Subsequent analysis was carried out on a gas chromatograph with electron capture detection and analytes were unequivocally confirmed by high resolution mass spectrometric detection. Hexachlorobenzene (HCB), trans-chlordane, 4,4′-DDD and 4,4′-DDE were detected after optimized HS-SPME in several water samples from the lower Delta at concentrations ranging from 2.4 to 61.4 μg L-1 that are much higher than the 0.1 μg L-1 maximum limit of individual organochlorine pesticides in drinking water set by the European Community Directive. The same samples were cleaned with ISOLUTE C18 SPE sorbent with an optimal acetone/n-hexane (1:1 v/v) mixture for the elution of analytes. No pesticides were detected after SPE clean-up and pre-concentration. HCB, aldrin and 4, 4‟-DDT were identified in sediments after SFE at concentration ranges of 1.1 - 30.3, 0.5 – 15.2 and 1.4 – 55.4 μg/g, respectively. There was an increase of pesticides concentrations in the direction of water flow from the Panhandle (point of entry) to the lower delta. DDE, fatty acids and phthalates were detected after PFE with optimized extraction solvent and temperature. The presence of DDT metabolites in the water and sediments from the Okavango Delta confirm historical exposure to the pesticide. However their cumulative concentration increase in the water-flow direction calls for further investigation of point sources for the long-term preservation of the Delta. The green sample preparation techniques and low toxicity solvents employed in this thesis are thus recommended for routine environmental monitoring exercises.
- Full Text:
The implementation of project work by selected grade 10 life science teachers in Namibia
- Authors: Angula, Alina Hambelela
- Date: 2009
- Subjects: Education -- Namibia Life sciences -- Study and teaching (Secondary) -- Namibia Project method in teaching -- Namibia School improvement programs -- Namibia Teachers -- Training of -- Namibia Curriculum planning -- Namibia Educational change -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1567 , http://hdl.handle.net/10962/d1003449
- Description: Prior to independence in Namibia in 1990 the education system of the day did not encourage the majority of Namibian learners to explore and investigate the wonder of the natural and physical world. The post independence education system has nurtured the study of the sciences and has emphasized participation, problem solving and independent studies. The inclusion of projects and other independent studies has been regarded as a key vehicle to develop scientific understanding and competencies related to this understanding. However, very few studies have hitherto investigated the teachers’ understanding and implementation of projects in the Namibian context. This study investigates how Grade 10 Life Science teachers understand and implement projects in selected schools in Namibia. The study focused on two teachers in two schools, a combined and a senior secondary school in the Oshikoto educational region of Namibia. The research was conducted through an interpretive case study aiming to gain a better understanding about the implementation of projects in schools. Data were collected through semi-structured interviews, classroom observation and document analysis. The findings indicate that despite the focus on projects in the Life Science syllabus and broad curriculum, policy documents do not give detailed guidelines on how projects should be planned, organized and assessed. The results revealed that knowledge about projects and their implementation is primarily informed by practical activities rather than the critical enquiries or investigations required by the Life Science curriculum policy. The study also revealed that despite the in-service training received by the two teachers participating in this study on syllabus interpretation, it is apparent from the findings that project work in these in-service programmes was neglected. This has further hampered teachers’ understanding and implementation of projects. The findings of this study point to a need for project guidelines as well as in-service programmes in this area if the stated nature and role of projects in the context of Namibian education policy is to be achieved.
- Full Text:
- Authors: Angula, Alina Hambelela
- Date: 2009
- Subjects: Education -- Namibia Life sciences -- Study and teaching (Secondary) -- Namibia Project method in teaching -- Namibia School improvement programs -- Namibia Teachers -- Training of -- Namibia Curriculum planning -- Namibia Educational change -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1567 , http://hdl.handle.net/10962/d1003449
- Description: Prior to independence in Namibia in 1990 the education system of the day did not encourage the majority of Namibian learners to explore and investigate the wonder of the natural and physical world. The post independence education system has nurtured the study of the sciences and has emphasized participation, problem solving and independent studies. The inclusion of projects and other independent studies has been regarded as a key vehicle to develop scientific understanding and competencies related to this understanding. However, very few studies have hitherto investigated the teachers’ understanding and implementation of projects in the Namibian context. This study investigates how Grade 10 Life Science teachers understand and implement projects in selected schools in Namibia. The study focused on two teachers in two schools, a combined and a senior secondary school in the Oshikoto educational region of Namibia. The research was conducted through an interpretive case study aiming to gain a better understanding about the implementation of projects in schools. Data were collected through semi-structured interviews, classroom observation and document analysis. The findings indicate that despite the focus on projects in the Life Science syllabus and broad curriculum, policy documents do not give detailed guidelines on how projects should be planned, organized and assessed. The results revealed that knowledge about projects and their implementation is primarily informed by practical activities rather than the critical enquiries or investigations required by the Life Science curriculum policy. The study also revealed that despite the in-service training received by the two teachers participating in this study on syllabus interpretation, it is apparent from the findings that project work in these in-service programmes was neglected. This has further hampered teachers’ understanding and implementation of projects. The findings of this study point to a need for project guidelines as well as in-service programmes in this area if the stated nature and role of projects in the context of Namibian education policy is to be achieved.
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Bones of contention : contestations over human remains in the Eastern Cape
- Authors: Mkhize, Nomalanga
- Date: 2007
- Subjects: Dead -- Political aspects -- South Africa Human body -- Symbolic aspects Human remains (Archaeology) -- Repatriation Human remains (Archaeology) -- Repatriation -- South Africa -- Eastern Cape Xhosa (African people) -- Social life and customs Eastern Cape (South Africa) -- Social life and customs Eastern Cape (South Africa) -- History
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2597 , http://hdl.handle.net/10962/d1007665
- Description: This thesis examines three contestations involving human remains which have arisen in the Eastern Cape over the past fifteen years. It shows that the value or meaning attached to human remains is constructed through the socio-historical dynamics out of which these contestations arise. The meaning and value of human remains is neither inherent nor neutral. In Ndancama's case, the need for housing in Fingo Village led hundreds of poor residents to settle on the township's Old Cemetery in 1972. Basic material needs trumped concerns for those buried in the cemetery. When the post-apartheid municipality sought to provide sewerage and housing infrastructure for Ndancama in 2003, its development plans were constrained by new heritage legislation which protects historic cemeteries. Residents insisted that their infrastructural needs were of primary importance. In 1993, the unearthing of human remains at the Old Military Cemetery in King William's Town created a thirteen year long saga which was only resolved with the reburial of the remains in 2006. The presence of the remains proved problematic for a number of reasons. Local authorities failed to rebury the remains speedily. The burden to store them fell on the Kaffrarian Museum which came under fire because this was considered unethical in the postapartheid era. The identity of the remains became a bone of contention in 2006 when the new Amathole District Municipality concluded that the remains were those of victims who died in the 1856-57 Great Cattle Killing. The remains and their reburial became symbols of past injustice and present restoration of African heritage. The 1996 quest by 'Nicholas Gcaleka', a 'self-styled' chief and traditional healer, to search for King Hintsa's skull in the United Kingdom provoked unprecedented public engagement with the incomplete narrative on the fate of Hintsa's body. The power to represent history, and the methods through which historical truth is discovered were at the heart of the contestation. Elites such as the Xhosa Royal and the white scientific establishment were considered neither credible nor authoritative on this historical matter. Public support for Gcaleka revealed that many South Africans sought just recompense for colonial injustices.
- Full Text:
- Authors: Mkhize, Nomalanga
- Date: 2007
- Subjects: Dead -- Political aspects -- South Africa Human body -- Symbolic aspects Human remains (Archaeology) -- Repatriation Human remains (Archaeology) -- Repatriation -- South Africa -- Eastern Cape Xhosa (African people) -- Social life and customs Eastern Cape (South Africa) -- Social life and customs Eastern Cape (South Africa) -- History
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2597 , http://hdl.handle.net/10962/d1007665
- Description: This thesis examines three contestations involving human remains which have arisen in the Eastern Cape over the past fifteen years. It shows that the value or meaning attached to human remains is constructed through the socio-historical dynamics out of which these contestations arise. The meaning and value of human remains is neither inherent nor neutral. In Ndancama's case, the need for housing in Fingo Village led hundreds of poor residents to settle on the township's Old Cemetery in 1972. Basic material needs trumped concerns for those buried in the cemetery. When the post-apartheid municipality sought to provide sewerage and housing infrastructure for Ndancama in 2003, its development plans were constrained by new heritage legislation which protects historic cemeteries. Residents insisted that their infrastructural needs were of primary importance. In 1993, the unearthing of human remains at the Old Military Cemetery in King William's Town created a thirteen year long saga which was only resolved with the reburial of the remains in 2006. The presence of the remains proved problematic for a number of reasons. Local authorities failed to rebury the remains speedily. The burden to store them fell on the Kaffrarian Museum which came under fire because this was considered unethical in the postapartheid era. The identity of the remains became a bone of contention in 2006 when the new Amathole District Municipality concluded that the remains were those of victims who died in the 1856-57 Great Cattle Killing. The remains and their reburial became symbols of past injustice and present restoration of African heritage. The 1996 quest by 'Nicholas Gcaleka', a 'self-styled' chief and traditional healer, to search for King Hintsa's skull in the United Kingdom provoked unprecedented public engagement with the incomplete narrative on the fate of Hintsa's body. The power to represent history, and the methods through which historical truth is discovered were at the heart of the contestation. Elites such as the Xhosa Royal and the white scientific establishment were considered neither credible nor authoritative on this historical matter. Public support for Gcaleka revealed that many South Africans sought just recompense for colonial injustices.
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An investigation of the relative importance of the media in influencing the voting behaviour of Evelyn Hone College students in Lusaka during the December, 2001 presidential elections in Zambia
- Authors: Jere, Caesar
- Date: 2003
- Subjects: Voting -- Zambia Mass media -- Political aspects -- Zambia Presidents -- Zambia -- Election -- 2001
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3516 , http://hdl.handle.net/10962/d1007803
- Description: This study explores the relative importance of the media in influencing the electoral choices of a small group of Zambians, namely Evelyn Hone College students in Lusaka who participated in the December 2001 elections in Zambia. The study investigates the interplay of mediation between the lived cultural experiences of the sample of students and the impact of media messages. Students at Evelyn Hone College come from different ethnic groupings, social classes, religions and regions. They are exposed to both the state and the privately owned media, which represent a range of political viewpoints. The outcome of the December 2001 elections in Zambia gave the impression that people in urban areas in Zambia were less likely to vote on ethnic lines because they had easy access to different media, ranging from print to electronic, which provided them with diverse information about the political scene, and probably shaped their electoral choices. Conversely, their counterparts in the rural areas appeared to vote along ethnic lines, seemingly because of lack of exposure to the media. It was also assumed that most people in rural areas were not as modernized as their urban counterparts who were more exposed to enlightened sources of information such as professional groups and other elite social institutions which helped them to shape their political opinions than most rural people. The study attempts to establish to what extent the media impacted on the selected sample of urban students in the choice of their presidential candidates in the December 2001 elections in Zambia. The study further investigates to what extent other factors such as ethnic inclinations and other social predispositions influenced them in their choice of the candidates. The interviewees for this study were randomly drawn from a population of Evelyn Hone College students that voted in the December 2001 presidential elections in Zambia. The sample consisted of 30 randomly selected students who were purposely stratified in three focus groups of ten each. Each stratum represented the approximate ethnic equivalence of one of the presidential candidates who contested the December 2001 elections.
- Full Text:
- Authors: Jere, Caesar
- Date: 2003
- Subjects: Voting -- Zambia Mass media -- Political aspects -- Zambia Presidents -- Zambia -- Election -- 2001
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3516 , http://hdl.handle.net/10962/d1007803
- Description: This study explores the relative importance of the media in influencing the electoral choices of a small group of Zambians, namely Evelyn Hone College students in Lusaka who participated in the December 2001 elections in Zambia. The study investigates the interplay of mediation between the lived cultural experiences of the sample of students and the impact of media messages. Students at Evelyn Hone College come from different ethnic groupings, social classes, religions and regions. They are exposed to both the state and the privately owned media, which represent a range of political viewpoints. The outcome of the December 2001 elections in Zambia gave the impression that people in urban areas in Zambia were less likely to vote on ethnic lines because they had easy access to different media, ranging from print to electronic, which provided them with diverse information about the political scene, and probably shaped their electoral choices. Conversely, their counterparts in the rural areas appeared to vote along ethnic lines, seemingly because of lack of exposure to the media. It was also assumed that most people in rural areas were not as modernized as their urban counterparts who were more exposed to enlightened sources of information such as professional groups and other elite social institutions which helped them to shape their political opinions than most rural people. The study attempts to establish to what extent the media impacted on the selected sample of urban students in the choice of their presidential candidates in the December 2001 elections in Zambia. The study further investigates to what extent other factors such as ethnic inclinations and other social predispositions influenced them in their choice of the candidates. The interviewees for this study were randomly drawn from a population of Evelyn Hone College students that voted in the December 2001 presidential elections in Zambia. The sample consisted of 30 randomly selected students who were purposely stratified in three focus groups of ten each. Each stratum represented the approximate ethnic equivalence of one of the presidential candidates who contested the December 2001 elections.
- Full Text:
Phytochemical studies on certain South African species of the rutaceous genera Agathosma Willd. and Zanthoxylum L
- Authors: Finkelstein, Nathan
- Date: 1979
- Subjects: Zanthoxylum Rutaceae
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3725 , http://hdl.handle.net/10962/d1001460
- Description: Selected species of two South African rutaceous genera, Agathosma Willd. and Zanthoxylum L., were phytochemically studied. Two species of the former genus, A. puberula (Steud.) Fourc . and A. elavisepala R. A. Dyer, yielded a novel O-prenylcoumarin, puberul in, the structure of which was fully elucidated as 6,8- dimethoxy-7-prenyloxycoumarin. This represents the first report of a coumarin from that endemic genus. In another study the alkaloids in three species of Zanthoxylum, Z. davyi (Verdoorn) Waterm., Z. thorneroftii (Verdoorn) Waterm. and Z. humile (E .A. Bruce) Waterm . , were investigated. Chelerythrine, nitidine, (-) -α-N-methylcanadine, (+)-laurifoline and (+)-magnoflorine were isolated and characterized in the stem and root bark of Z. davyi, while the root bark of Z. thorneroftii contained skimmianine and decarine in addition to the alkaloids present in Z. davyi. Skimmianine, decarine, N-norchelerythrine, chelerythrine, (-)-α-N-methylcanadinc, candicine and tembetarine were identified in the root bark of Z. humile. The chemotaxonomic significance of these alkaloids occurring in the South African taxa in relation to other African Zanthoxylum taxa, is discussed. Several non-alkaloids (lupeol, β-sitosterol and (-)-sesamin) were also isolated and characterized in Z. davyi and Z. humile. Horizontal cellulose column chromatography and low pressure liquid chromatography have been applied to the separation of quaternary alkaloids
- Full Text:
- Authors: Finkelstein, Nathan
- Date: 1979
- Subjects: Zanthoxylum Rutaceae
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3725 , http://hdl.handle.net/10962/d1001460
- Description: Selected species of two South African rutaceous genera, Agathosma Willd. and Zanthoxylum L., were phytochemically studied. Two species of the former genus, A. puberula (Steud.) Fourc . and A. elavisepala R. A. Dyer, yielded a novel O-prenylcoumarin, puberul in, the structure of which was fully elucidated as 6,8- dimethoxy-7-prenyloxycoumarin. This represents the first report of a coumarin from that endemic genus. In another study the alkaloids in three species of Zanthoxylum, Z. davyi (Verdoorn) Waterm., Z. thorneroftii (Verdoorn) Waterm. and Z. humile (E .A. Bruce) Waterm . , were investigated. Chelerythrine, nitidine, (-) -α-N-methylcanadine, (+)-laurifoline and (+)-magnoflorine were isolated and characterized in the stem and root bark of Z. davyi, while the root bark of Z. thorneroftii contained skimmianine and decarine in addition to the alkaloids present in Z. davyi. Skimmianine, decarine, N-norchelerythrine, chelerythrine, (-)-α-N-methylcanadinc, candicine and tembetarine were identified in the root bark of Z. humile. The chemotaxonomic significance of these alkaloids occurring in the South African taxa in relation to other African Zanthoxylum taxa, is discussed. Several non-alkaloids (lupeol, β-sitosterol and (-)-sesamin) were also isolated and characterized in Z. davyi and Z. humile. Horizontal cellulose column chromatography and low pressure liquid chromatography have been applied to the separation of quaternary alkaloids
- Full Text:
A critical study of the chansons of the Chatelain de Couci (end of the XIIth to beginning of the XIIIth Century)
- Authors: Salter, Christina
- Date: 1973
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:21144 , http://hdl.handle.net/10962/6563
- Full Text:
- Authors: Salter, Christina
- Date: 1973
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:21144 , http://hdl.handle.net/10962/6563
- Full Text:
An investigation into the application of Austrian didactics and methods of elementary musical education in South African school
- Authors: Nowotny, Ingrid Heidelinde
- Date: 1970
- Subjects: School music -- Instruction and study -- South Africa , Music -- Study and teaching (Elementary) , Music theory -- Elementary works
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2688 , http://hdl.handle.net/10962/d1012970
- Description: Why teach music? To answer this question one has to be able to see the full value of musical education. One has to recognize its effect on the unfolding of character and personality on the one hand and, on the other, its value for the development and sharpening of the intellect. In ancient Greece, the cradle of Western culture, the significance of music for man, the people, and the state was frequently emphasized. The Greeks regarded music almost as a magic force, the inherent harmony of which was capable of transforming things and creating order by reconciling contrarieties. Similarly they believed that the power of music could restore the harmony in man's soul. Intro., p.1.
- Full Text:
- Authors: Nowotny, Ingrid Heidelinde
- Date: 1970
- Subjects: School music -- Instruction and study -- South Africa , Music -- Study and teaching (Elementary) , Music theory -- Elementary works
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2688 , http://hdl.handle.net/10962/d1012970
- Description: Why teach music? To answer this question one has to be able to see the full value of musical education. One has to recognize its effect on the unfolding of character and personality on the one hand and, on the other, its value for the development and sharpening of the intellect. In ancient Greece, the cradle of Western culture, the significance of music for man, the people, and the state was frequently emphasized. The Greeks regarded music almost as a magic force, the inherent harmony of which was capable of transforming things and creating order by reconciling contrarieties. Similarly they believed that the power of music could restore the harmony in man's soul. Intro., p.1.
- Full Text:
Activity rhythms in the larvae of myrmeleon obscurus ramb : (neuroptera, myrmeleontidae)
- Authors: Morrison, G J
- Date: 1968
- Subjects: Ant lions , Myrmeleon
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5868 , http://hdl.handle.net/10962/d1012906
- Description: 1) An investigation was undertaken into the various activity rhythms found in the larvae of Myrmeleon obscurus (Neuroptera, Myrmeleontidae). Pit construction was used as the criterion of activity. 2) The capacity sensitive electronic circuit used to monitor the daily pit building activity is described. 3) Various factors affecting the size of the pits constructed by ant-lion larvae were investigated. Pit size was found to be correlated with the size of the larvae, larger larvae constructing bigger pits. Population size was also shown to have an effect, since the more crowded the animals were the smaller and closer together their pits became. The death rate due to competition between the larvae also increased as the ant-lions became more crowded. 4) Feeding frequency also affected pit size. Ant-lions which were starved constructed very small pits. 5) Pit size was affected by the texture of the sand, maximal pit size being attained in sand with a grain size of between 353 μ and 211 μ. This was shown to be the most abundant grain size in sand from the natural habitat. In sand coarser or finer than this, pit size was reduced. 6) Generally smaller pits were constructed at lower temperatures, but this response depended largely on the lunar cycle. The upper and lower critical limits for pit construction were found to be 11° C and 42° C. Below and above these temperatures no pits were constructed, although the ant-lions remained alive. 7) Daily destruction of the pits decreased the pit size. 8) The existence of the daily pit building activity rhythm, which occurs at dusk, was demonstrated in individuals and in populations of ant-lion larvae. This rhythm was studied using the capacity sensitive circuit, and also by direct observation of groups of animals over a 24 hour period. 9) The daily activity rhythm appeared to be endogenous, since it continued for at least a month both in constant light and in constant dark. The rhythm was altered by reversals in the daily light-dark cycle, and it was concluded that light was the main phase setting factor. 10) An attempt was made to determine the location of the "clock" or "clocks" controlling the daily activity rhythm. This was investigated by chilling the heads of individual ant-lions with a fine copper wire, and also by chilling large groups of animals in the refrigerator. From these experiments no definite conclusions could be drawn about the location of the "clock". 11) The existence of a lunar pit building cycle was demonstrated in both field and laboratory populations of ant-lions. Maximal pit size was attained at full moon. Very low temperatures were found to suppress these lunar peaks. 12) The lunar pit building rhythm was shown to be endogenous, since it continued for at least two months in constant dark and one month in constant light. 13) The lunar pit building rhythm of very young larvae was investigated, and it was shown that while larvae which hatched in the field appeared to possess a lunar rhythm, larvae which were hatched in the laboratory did not have a rhythm. It was therefore concluded that the light of the moon was necessary to establish the lunar rhythm. 14) Some possible explanations for the lunar cycle were investigated experimentally. It was concluded that the lunar rhythm was not related to the number of prey present at various times of the lunar cycle or to the spacing of the animals in their habitat. The lunar rhythm was shown to be due to the combination of a lunar day activity rhythm and a solar day activity rhythm. 15) Some aspects of the daily rhythm are discussed, and this rhythm is compared with those found in other insects. Probable functional reasons for the rhythm are presented. Summary, p. 133-136.
- Full Text:
- Authors: Morrison, G J
- Date: 1968
- Subjects: Ant lions , Myrmeleon
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5868 , http://hdl.handle.net/10962/d1012906
- Description: 1) An investigation was undertaken into the various activity rhythms found in the larvae of Myrmeleon obscurus (Neuroptera, Myrmeleontidae). Pit construction was used as the criterion of activity. 2) The capacity sensitive electronic circuit used to monitor the daily pit building activity is described. 3) Various factors affecting the size of the pits constructed by ant-lion larvae were investigated. Pit size was found to be correlated with the size of the larvae, larger larvae constructing bigger pits. Population size was also shown to have an effect, since the more crowded the animals were the smaller and closer together their pits became. The death rate due to competition between the larvae also increased as the ant-lions became more crowded. 4) Feeding frequency also affected pit size. Ant-lions which were starved constructed very small pits. 5) Pit size was affected by the texture of the sand, maximal pit size being attained in sand with a grain size of between 353 μ and 211 μ. This was shown to be the most abundant grain size in sand from the natural habitat. In sand coarser or finer than this, pit size was reduced. 6) Generally smaller pits were constructed at lower temperatures, but this response depended largely on the lunar cycle. The upper and lower critical limits for pit construction were found to be 11° C and 42° C. Below and above these temperatures no pits were constructed, although the ant-lions remained alive. 7) Daily destruction of the pits decreased the pit size. 8) The existence of the daily pit building activity rhythm, which occurs at dusk, was demonstrated in individuals and in populations of ant-lion larvae. This rhythm was studied using the capacity sensitive circuit, and also by direct observation of groups of animals over a 24 hour period. 9) The daily activity rhythm appeared to be endogenous, since it continued for at least a month both in constant light and in constant dark. The rhythm was altered by reversals in the daily light-dark cycle, and it was concluded that light was the main phase setting factor. 10) An attempt was made to determine the location of the "clock" or "clocks" controlling the daily activity rhythm. This was investigated by chilling the heads of individual ant-lions with a fine copper wire, and also by chilling large groups of animals in the refrigerator. From these experiments no definite conclusions could be drawn about the location of the "clock". 11) The existence of a lunar pit building cycle was demonstrated in both field and laboratory populations of ant-lions. Maximal pit size was attained at full moon. Very low temperatures were found to suppress these lunar peaks. 12) The lunar pit building rhythm was shown to be endogenous, since it continued for at least two months in constant dark and one month in constant light. 13) The lunar pit building rhythm of very young larvae was investigated, and it was shown that while larvae which hatched in the field appeared to possess a lunar rhythm, larvae which were hatched in the laboratory did not have a rhythm. It was therefore concluded that the light of the moon was necessary to establish the lunar rhythm. 14) Some possible explanations for the lunar cycle were investigated experimentally. It was concluded that the lunar rhythm was not related to the number of prey present at various times of the lunar cycle or to the spacing of the animals in their habitat. The lunar rhythm was shown to be due to the combination of a lunar day activity rhythm and a solar day activity rhythm. 15) Some aspects of the daily rhythm are discussed, and this rhythm is compared with those found in other insects. Probable functional reasons for the rhythm are presented. Summary, p. 133-136.
- Full Text:
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