How policy discourses and contextual realities influence environmental teaching and learning processes in early childhood development: a case study of the Raglan Road child care centre
- Authors: Vallabh, Priya
- Date: 2005
- Subjects: Early childhood education -- South Africa , Health education -- South Africa , Environmental education -- Study and teaching -- South Africa , Day care centers -- South Africa , Child development
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1559 , http://hdl.handle.net/10962/d1003441 , Early childhood education -- South Africa , Health education -- South Africa , Environmental education -- Study and teaching -- South Africa , Day care centers -- South Africa , Child development
- Description: This case study considers the relationship between context, school policy and environmental teaching and learning processes at a community-based early childhood development centre in South Africa. The study recognises that educational practices in the early childhood development field are shaped by historical, cultural, economic and political realities at both local and national levels. It is from the understanding that each school is a unique composition of these shaping factors that the research was designed to consider the community-based school participating in this study. By compiling a contextual profile, this study attempts to consider dominant contextual factors affecting the school. Through the critical discourse analysis of a school policy document, this study considers local level policy, and through the literature chapter, national policy. Teacher interviews provide insight into teacher understanding of school policy in response to contextual issues, as well as providing insight into how teachers perceive their translation of policy into teaching practice. Observations of lessons in the centre provided an. opportunity to see how context and policy translated into and influenced environmental teaching and learning processes. This study looks at how environmental education is addressed in the Raglan Road Child Care Centre, and provides insight into how environmental education within the context of the school and in relation to school policy may be strengthened. It comments on the tensions and ambivalences arising from the relationships between context, policy and environmental teaching and learning processes and makes recommendations to address these ambivalences in ways that are contextually relevant. The main recommendations were designed to be practically useful for the school involved in the study and are focused around engaging the ambivalences emerging from this study to open up 'spaces' for deliberating environmental teaching and learning processes and other tensions arising out of the study at an ECD level. Recommendations included: 1) engaging with the strong development focus in school policy and the educational focus in national policy and teacher discourse; 2) deliberating the ways in which school policy and national policy respond to risk; 3) engaging with the ambivalence in the school-parent relationship; 4) the re-alignment of the explicit curriculum and broadening the contextually-based view of whole child development; and 5) engaging the ambivalence in approaches to education at the centre.
- Full Text:
- Date Issued: 2005
- Authors: Vallabh, Priya
- Date: 2005
- Subjects: Early childhood education -- South Africa , Health education -- South Africa , Environmental education -- Study and teaching -- South Africa , Day care centers -- South Africa , Child development
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1559 , http://hdl.handle.net/10962/d1003441 , Early childhood education -- South Africa , Health education -- South Africa , Environmental education -- Study and teaching -- South Africa , Day care centers -- South Africa , Child development
- Description: This case study considers the relationship between context, school policy and environmental teaching and learning processes at a community-based early childhood development centre in South Africa. The study recognises that educational practices in the early childhood development field are shaped by historical, cultural, economic and political realities at both local and national levels. It is from the understanding that each school is a unique composition of these shaping factors that the research was designed to consider the community-based school participating in this study. By compiling a contextual profile, this study attempts to consider dominant contextual factors affecting the school. Through the critical discourse analysis of a school policy document, this study considers local level policy, and through the literature chapter, national policy. Teacher interviews provide insight into teacher understanding of school policy in response to contextual issues, as well as providing insight into how teachers perceive their translation of policy into teaching practice. Observations of lessons in the centre provided an. opportunity to see how context and policy translated into and influenced environmental teaching and learning processes. This study looks at how environmental education is addressed in the Raglan Road Child Care Centre, and provides insight into how environmental education within the context of the school and in relation to school policy may be strengthened. It comments on the tensions and ambivalences arising from the relationships between context, policy and environmental teaching and learning processes and makes recommendations to address these ambivalences in ways that are contextually relevant. The main recommendations were designed to be practically useful for the school involved in the study and are focused around engaging the ambivalences emerging from this study to open up 'spaces' for deliberating environmental teaching and learning processes and other tensions arising out of the study at an ECD level. Recommendations included: 1) engaging with the strong development focus in school policy and the educational focus in national policy and teacher discourse; 2) deliberating the ways in which school policy and national policy respond to risk; 3) engaging with the ambivalence in the school-parent relationship; 4) the re-alignment of the explicit curriculum and broadening the contextually-based view of whole child development; and 5) engaging the ambivalence in approaches to education at the centre.
- Full Text:
- Date Issued: 2005
Psychologists perceptions of English-speaking South African’s potential meaning attached to post-traumatic stress disorder symptoms
- Authors: Le Roux, Carmen Jade
- Date: 2021-04
- Subjects: Post-traumatic stress disorder -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/51276 , vital:43259
- Description: South Africa is characterised by high levels of trauma and multiple forms of violence exposure which are said to be causal factors in post-traumatic stress disorder (PTSD). Culture is imperative in constructing the reality of individuals as it provides the templates which are used to describe, understand, predict, and control the world within which individuals exist. Culture is regarded as being influential on the ways in which individuals ascribe meaning and make sense of their traumatic experiences and symptoms. Culture is also integral to the healing process as it influences and guides the illness narrative created by individuals. The aim of this study is to understand the potential meanings attached to PTSD symptoms and the role of culture on these meaning ascriptions. These meanings are explored through the perception of Mental Healthcare Practitioners. The study uses qualitative methodology; specifically, an exploratory and descriptive design. The sample is identified through non-probability purposive sampling, and the data is collected through semi-structured interviews. The data is analysed using thematic analysis which identified major themes of understanding and acceptance. These themes followed a non-linear and interactive process, and present participants ascribing varying meanings to their trauma experience, PTSD symptoms and/or PTSD diagnosis. These meanings are discussed through the interpretivist lens of social constructionism. The findings of the study identified that individuals within the white English-speaking cultural group tend to understand their traumatic experience, their symptoms of PTSD and/or their PTSD diagnosis from an individualistic frame of reference, whilst individuals from the coloured English speaking cultural group tend to understand their traumatic experience, their symptoms of PTSD and/or their PTSD diagnosis from a collective frame of reference. , Thesis (MA) -- Faculty of Health Sciences, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Le Roux, Carmen Jade
- Date: 2021-04
- Subjects: Post-traumatic stress disorder -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/51276 , vital:43259
- Description: South Africa is characterised by high levels of trauma and multiple forms of violence exposure which are said to be causal factors in post-traumatic stress disorder (PTSD). Culture is imperative in constructing the reality of individuals as it provides the templates which are used to describe, understand, predict, and control the world within which individuals exist. Culture is regarded as being influential on the ways in which individuals ascribe meaning and make sense of their traumatic experiences and symptoms. Culture is also integral to the healing process as it influences and guides the illness narrative created by individuals. The aim of this study is to understand the potential meanings attached to PTSD symptoms and the role of culture on these meaning ascriptions. These meanings are explored through the perception of Mental Healthcare Practitioners. The study uses qualitative methodology; specifically, an exploratory and descriptive design. The sample is identified through non-probability purposive sampling, and the data is collected through semi-structured interviews. The data is analysed using thematic analysis which identified major themes of understanding and acceptance. These themes followed a non-linear and interactive process, and present participants ascribing varying meanings to their trauma experience, PTSD symptoms and/or PTSD diagnosis. These meanings are discussed through the interpretivist lens of social constructionism. The findings of the study identified that individuals within the white English-speaking cultural group tend to understand their traumatic experience, their symptoms of PTSD and/or their PTSD diagnosis from an individualistic frame of reference, whilst individuals from the coloured English speaking cultural group tend to understand their traumatic experience, their symptoms of PTSD and/or their PTSD diagnosis from a collective frame of reference. , Thesis (MA) -- Faculty of Health Sciences, 2021
- Full Text:
- Date Issued: 2021-04
Sources of advertisement messages and their impacts on purchasing behaviour:A case study of Walter Sisulu University students
- Oladimeji, Olawumi Kate https://orcid.org/0000-0002-6577-0140
- Authors: Oladimeji, Olawumi Kate https://orcid.org/0000-0002-6577-0140
- Date: 2013-11
- Subjects: Mass Media -- Social Aspect , Advertising -- Social Aspects
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/23203 , vital:55898
- Description: The purpose of this research was to investigate the sources of advertisement messages and the impacts they have on the buying behaviour of students of Walter Sisulu University (WSU) and examine whether traditional mass media advertising still influences the students’ decision to buy and whether advancement in communication technology affects how the students receive information. This study also investigated the impact of traditional mass media advertising in comparison to new media advertising. Questionnaires were administered to students of WSU, Mthatha campus. The survey was conducted within the period of February 2013 – March 2013. The desired sample size was 270 students. A final sample of 220 valid responses was analysed, representing 81 percent of the desired sample. The study revealed that majority are aware of television while billboards and direct mails have the least awareness. The results also revealed that 78 percent of the respondents felt that traditional mass media still influences their buying behaviour, (90 percent) of the respondents prefer the traditional mass media advertising. This study demonstrated that the students of WSU are aware and exposed to the various sources of advertisement messages. In addition, existing literature and this research report have shown that the various mediums have distinctive characteristics which make them unique. In spite of the advent of modern technology, the traditional mass media still influences buying behaviour with television being the most influential media. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2013
- Full Text:
- Date Issued: 2013-11
- Authors: Oladimeji, Olawumi Kate https://orcid.org/0000-0002-6577-0140
- Date: 2013-11
- Subjects: Mass Media -- Social Aspect , Advertising -- Social Aspects
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/23203 , vital:55898
- Description: The purpose of this research was to investigate the sources of advertisement messages and the impacts they have on the buying behaviour of students of Walter Sisulu University (WSU) and examine whether traditional mass media advertising still influences the students’ decision to buy and whether advancement in communication technology affects how the students receive information. This study also investigated the impact of traditional mass media advertising in comparison to new media advertising. Questionnaires were administered to students of WSU, Mthatha campus. The survey was conducted within the period of February 2013 – March 2013. The desired sample size was 270 students. A final sample of 220 valid responses was analysed, representing 81 percent of the desired sample. The study revealed that majority are aware of television while billboards and direct mails have the least awareness. The results also revealed that 78 percent of the respondents felt that traditional mass media still influences their buying behaviour, (90 percent) of the respondents prefer the traditional mass media advertising. This study demonstrated that the students of WSU are aware and exposed to the various sources of advertisement messages. In addition, existing literature and this research report have shown that the various mediums have distinctive characteristics which make them unique. In spite of the advent of modern technology, the traditional mass media still influences buying behaviour with television being the most influential media. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2013
- Full Text:
- Date Issued: 2013-11
Sources of advertisement messages and their impacts on purchasing behaviour: a case study of Walter Sisulu University students
- Oladimeji, Olawumi Kate https://orcid.org/0000-0002-6577-0140
- Authors: Oladimeji, Olawumi Kate https://orcid.org/0000-0002-6577-0140
- Date: 2013-11
- Subjects: Mass media -- Social aspects , Advertising -- Social aspects
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24824 , vital:63599
- Description: The purpose of this research was to investigate the sources of advertisement messages and the impacts they have on the buying behaviour of students of Walter Sisulu University (WSU), and examine whether traditional mass media advertising still influences the students’ decision to buy and whether advancement in communication technology affects how the students receive information. This study also investigated the impact of traditional mass media advertising in comparison to new media advertising. Questionnaires were administered to students of WSU, Mthatha campus. The survey was conducted within the period of February 2013 – March 2013. The desired sample size was 270 students. A final sample of 220 valid responses was analysed, representing 81percent of the desired sample. The study revealed that majority are aware of television while billboards and direct mails have the least awareness. The results also revealed that 78percent of the respondents felt that traditional mass media still influences their buying behaviour, (90percent) of the respondents prefer the traditional mass media advertising. This study demonstrated that the students of WSU are aware and exposed to the various sources of advertisement messages. In addition, existing literature and this research report have shown that the various mediums have distinctive characteristics which make them unique. In spite of the advent of modern technology, the traditional mass media still influences buying behaviour with television being the most influential media. , Thesis (MSoc) -- Faculty of Social Sciences and Humanities, 2013
- Full Text:
- Date Issued: 2013-11
- Authors: Oladimeji, Olawumi Kate https://orcid.org/0000-0002-6577-0140
- Date: 2013-11
- Subjects: Mass media -- Social aspects , Advertising -- Social aspects
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24824 , vital:63599
- Description: The purpose of this research was to investigate the sources of advertisement messages and the impacts they have on the buying behaviour of students of Walter Sisulu University (WSU), and examine whether traditional mass media advertising still influences the students’ decision to buy and whether advancement in communication technology affects how the students receive information. This study also investigated the impact of traditional mass media advertising in comparison to new media advertising. Questionnaires were administered to students of WSU, Mthatha campus. The survey was conducted within the period of February 2013 – March 2013. The desired sample size was 270 students. A final sample of 220 valid responses was analysed, representing 81percent of the desired sample. The study revealed that majority are aware of television while billboards and direct mails have the least awareness. The results also revealed that 78percent of the respondents felt that traditional mass media still influences their buying behaviour, (90percent) of the respondents prefer the traditional mass media advertising. This study demonstrated that the students of WSU are aware and exposed to the various sources of advertisement messages. In addition, existing literature and this research report have shown that the various mediums have distinctive characteristics which make them unique. In spite of the advent of modern technology, the traditional mass media still influences buying behaviour with television being the most influential media. , Thesis (MSoc) -- Faculty of Social Sciences and Humanities, 2013
- Full Text:
- Date Issued: 2013-11
Sources of advertisement messages and their impacts on purchasing behaviour: a case study of Walter Sisulu University students
- Authors: Oladimeji, Olawumi Kate
- Date: 2014
- Language: English
- Type: Thesis , Masters , M Soc Sc (Com)
- Identifier: vital:11371 , http://hdl.handle.net/10353/d1015413
- Description: The purpose of this research was to investigate the sources of advertisement messages and the impacts they have on the buying behaviour of students of Walter Sisulu University (WSU), and examine whether traditional mass media advertising still influences the students’ decision to buy and whether advancement in communication technology affects how the students receive information. This study also investigated the impact of traditional mass media advertising in comparison to new media advertising. Questionnaires were administered to students of WSU, Mthatha campus. The survey was conducted within the period of February 2013 – March 2013. The desired sample size was 270 students. A final sample of 220 valid responses was analysed, representing 81% of the desired sample. The study revealed that majority are aware of television while billboards and direct mails have the least awareness. The results also revealed that 78% of the respondents felt that traditional mass media still influences their buying behaviour, (90%) of the respondents prefer the traditional mass media advertising. This study demonstrated that the students of WSU are aware and exposed to the various sources of advertisement messages. In addition, existing literature and this research report have shown that the various mediums have distinctive characteristics which make them unique. In spite of the advent of modern technology, the traditional mass media still influences buying behaviour with television being the most influential media.
- Full Text:
- Date Issued: 2014
- Authors: Oladimeji, Olawumi Kate
- Date: 2014
- Language: English
- Type: Thesis , Masters , M Soc Sc (Com)
- Identifier: vital:11371 , http://hdl.handle.net/10353/d1015413
- Description: The purpose of this research was to investigate the sources of advertisement messages and the impacts they have on the buying behaviour of students of Walter Sisulu University (WSU), and examine whether traditional mass media advertising still influences the students’ decision to buy and whether advancement in communication technology affects how the students receive information. This study also investigated the impact of traditional mass media advertising in comparison to new media advertising. Questionnaires were administered to students of WSU, Mthatha campus. The survey was conducted within the period of February 2013 – March 2013. The desired sample size was 270 students. A final sample of 220 valid responses was analysed, representing 81% of the desired sample. The study revealed that majority are aware of television while billboards and direct mails have the least awareness. The results also revealed that 78% of the respondents felt that traditional mass media still influences their buying behaviour, (90%) of the respondents prefer the traditional mass media advertising. This study demonstrated that the students of WSU are aware and exposed to the various sources of advertisement messages. In addition, existing literature and this research report have shown that the various mediums have distinctive characteristics which make them unique. In spite of the advent of modern technology, the traditional mass media still influences buying behaviour with television being the most influential media.
- Full Text:
- Date Issued: 2014
The influence of social media service quality on client loyalty in the South African banking industry
- Authors: Gavaza, Bramwell Kundishora
- Date: 2017
- Subjects: Banks and banking -- South Africa Social media -- South Africa Customer loyalty -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10353/12903 , vital:39389
- Description: The advent of the Internet during the past two decades has changed the way in which businesses operate. Social media networks such as Facebook have become an essential communication element for businesses to interact with clients. The impact and growth rates of Facebook and other forms of social media have made it imperative for all businesses to ensure they have social media strategies in place. Following social media business trends, banks across the world have included social media to market their services. Banks are now emphasising the offering of high client service quality in order to retain clients in this highly competitive environment. Thus, South African banks, as is the case with global banks, need to continuously assess the quality of the services offered to their clients in order to sustainably maintain or grow their market share or to fully utilise its commercial opportunities. This study determined the influence of social media service quality on client loyalty in the South African banking industry. The primary objective was to examine the extent to which social media service quality influence client loyalty in the South African banking industry. The study also determined if social media system availability, efficiency, fulfilment, and privacy has influence on the overall service quality of social media in the South African banking industry. In addition, the study examined the relationship between overall service quality and client loyalty intention in the South African banking industry. The study used a quantitative research approach to collect and analyse the data, and a descriptive research design was utilised for the purpose of this study. Data was collected from both primary and secondary sources of data. An online survey was conducted through Survey Monkey, via a Facebook page titled: Social media service quality in the South African banking industry. An online questionnaire was administered via the Facebook page. The study used a sample of 377 respondents who are Facebook users of the five major banks in South Africa. Analysis and interpretation of findings was done using both the descriptive and inferential statistical measures, with the help of Statistical Package for Social Scientists (SPSS) 24 and Lisrel (version 9). The electronic social media service quality (E-S-SERVQUAL) scale which consist of five constructs, namely; social media system availability, efficiency, fulfilment, privacy and overall service quality; and client loyalty intentions were the scales that were adopted for this study. All the scales used in this study were found to be reliable and valid. Findings of the research study proved that social media system availability, fulfilment, and privacy has a significant influence on the overall service quality of social media in the South African banking industry. In addition, findings of the research revealed that social media efficiency does not significantly influence overall service quality of social media in the South African banking industry. Furthermore, findings of the research also proved that the overall service quality of social media positively influences client loyalty intention in the South African banking industry. The study recommended that managers and marketers should constantly evaluate, monitor, and improve the overall service quality of social media offered to their clients, as it leads to a corresponding increase in overall client satisfaction, which in turn leads to client loyalty in the South African banking industry. However, further research studies may be conducted in other developing countries to gain a wider understanding on the influence of social media service quality on client loyalty in the banking industry.
- Full Text:
- Date Issued: 2017
- Authors: Gavaza, Bramwell Kundishora
- Date: 2017
- Subjects: Banks and banking -- South Africa Social media -- South Africa Customer loyalty -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10353/12903 , vital:39389
- Description: The advent of the Internet during the past two decades has changed the way in which businesses operate. Social media networks such as Facebook have become an essential communication element for businesses to interact with clients. The impact and growth rates of Facebook and other forms of social media have made it imperative for all businesses to ensure they have social media strategies in place. Following social media business trends, banks across the world have included social media to market their services. Banks are now emphasising the offering of high client service quality in order to retain clients in this highly competitive environment. Thus, South African banks, as is the case with global banks, need to continuously assess the quality of the services offered to their clients in order to sustainably maintain or grow their market share or to fully utilise its commercial opportunities. This study determined the influence of social media service quality on client loyalty in the South African banking industry. The primary objective was to examine the extent to which social media service quality influence client loyalty in the South African banking industry. The study also determined if social media system availability, efficiency, fulfilment, and privacy has influence on the overall service quality of social media in the South African banking industry. In addition, the study examined the relationship between overall service quality and client loyalty intention in the South African banking industry. The study used a quantitative research approach to collect and analyse the data, and a descriptive research design was utilised for the purpose of this study. Data was collected from both primary and secondary sources of data. An online survey was conducted through Survey Monkey, via a Facebook page titled: Social media service quality in the South African banking industry. An online questionnaire was administered via the Facebook page. The study used a sample of 377 respondents who are Facebook users of the five major banks in South Africa. Analysis and interpretation of findings was done using both the descriptive and inferential statistical measures, with the help of Statistical Package for Social Scientists (SPSS) 24 and Lisrel (version 9). The electronic social media service quality (E-S-SERVQUAL) scale which consist of five constructs, namely; social media system availability, efficiency, fulfilment, privacy and overall service quality; and client loyalty intentions were the scales that were adopted for this study. All the scales used in this study were found to be reliable and valid. Findings of the research study proved that social media system availability, fulfilment, and privacy has a significant influence on the overall service quality of social media in the South African banking industry. In addition, findings of the research revealed that social media efficiency does not significantly influence overall service quality of social media in the South African banking industry. Furthermore, findings of the research also proved that the overall service quality of social media positively influences client loyalty intention in the South African banking industry. The study recommended that managers and marketers should constantly evaluate, monitor, and improve the overall service quality of social media offered to their clients, as it leads to a corresponding increase in overall client satisfaction, which in turn leads to client loyalty in the South African banking industry. However, further research studies may be conducted in other developing countries to gain a wider understanding on the influence of social media service quality on client loyalty in the banking industry.
- Full Text:
- Date Issued: 2017
Mapping epistemic cultures and learning potential of participants in citizen science projects
- Vallabh, Priya, Lotz-Sisitka, Heila, O'Donoghue, Rob, Schudel, Ingrid J
- Authors: Vallabh, Priya , Lotz-Sisitka, Heila , O'Donoghue, Rob , Schudel, Ingrid J
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/128939 , vital:36192 , https://doi.org/10.1111/cobi.12701
- Description: The ever-widening scope and range of global change and interconnected systemic risks arising from people–environment relationships (social‐ecological risks) appears to be increasing concern among, and involvement of, citizens in an increasingly diversified number of citizen science projects responding to these risks. We examined the relationship between epistemic cultures in citizen science projects and learning potential related to matters of concern. We then developed a typology of purposes and a citizen science epistemic‐cultures heuristic and mapped 56 projects in southern Africa using this framework. The purpose typology represents the range of knowledge‐production purposes, ranging from laboratory science to social learning, whereas the epistemic‐cultures typology is a relational representation of scientist and citizen participation and their approach to knowledge production. Results showed an iterative relationship between matters of fact and matters of concern across the projects; the nexus of citizens’ engagement in knowledge‐production activities varied. The knowledge‐production purposes informed and shaped the epistemic cultures of all the sampled citizen science projects, which in turn influenced the potential for learning within each project. Through a historical review of 3 phases in a long‐term river health‐monitoring project, we found that it is possible to evolve the learning curve of citizen science projects. This evolution involved the development of scientific water monitoring tools, the parallel development of pedagogic practices supporting monitoring activities, and situated engagement around matters of concern within social activism leading to learning‐led change. We conclude that such evolutionary processes serve to increase potential for learning and are necessary if citizen science is to contribute to wider restructuring of the epistemic culture of science under conditions of expanding social-ecological risk.
- Full Text:
- Date Issued: 2016
- Authors: Vallabh, Priya , Lotz-Sisitka, Heila , O'Donoghue, Rob , Schudel, Ingrid J
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/128939 , vital:36192 , https://doi.org/10.1111/cobi.12701
- Description: The ever-widening scope and range of global change and interconnected systemic risks arising from people–environment relationships (social‐ecological risks) appears to be increasing concern among, and involvement of, citizens in an increasingly diversified number of citizen science projects responding to these risks. We examined the relationship between epistemic cultures in citizen science projects and learning potential related to matters of concern. We then developed a typology of purposes and a citizen science epistemic‐cultures heuristic and mapped 56 projects in southern Africa using this framework. The purpose typology represents the range of knowledge‐production purposes, ranging from laboratory science to social learning, whereas the epistemic‐cultures typology is a relational representation of scientist and citizen participation and their approach to knowledge production. Results showed an iterative relationship between matters of fact and matters of concern across the projects; the nexus of citizens’ engagement in knowledge‐production activities varied. The knowledge‐production purposes informed and shaped the epistemic cultures of all the sampled citizen science projects, which in turn influenced the potential for learning within each project. Through a historical review of 3 phases in a long‐term river health‐monitoring project, we found that it is possible to evolve the learning curve of citizen science projects. This evolution involved the development of scientific water monitoring tools, the parallel development of pedagogic practices supporting monitoring activities, and situated engagement around matters of concern within social activism leading to learning‐led change. We conclude that such evolutionary processes serve to increase potential for learning and are necessary if citizen science is to contribute to wider restructuring of the epistemic culture of science under conditions of expanding social-ecological risk.
- Full Text:
- Date Issued: 2016
Towards the Common Good: An expansive post-abyssal (Re)stor(y)ing of the epistemic cultures of the citizen sciences
- Authors: Vallabh, Priya
- Date: 2022-04-08
- Subjects: Science Citizen participation , Decolonization , Social epistemology , Hegemony , Common good , Traditional ecological knowledge , Ethnoscience
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/290671 , vital:56773 , DOI 10.21504/10962/290671
- Description: In this study I explore and explain transformatiThe citizen sciences convene complex and reflexive ecologies of knowledges in response to a range of social-ecological risks. Their epistemic cultures seem to be assembled in ways which increase potential mobilisation of the common knowledges being produced, thereby producing knowledges in forms that are more strongly aligned with a range of implementation strategies. However, much of such processes of knowledge production have been ‘cleaned out’ of official accounts through scientifically hegemonic systems of legitimation, deepening hegemonically-entrenched systems of epistemic, contributory and distributive injustices, and undermining the potential for stronger enactments of participatory and radical democracies. The engagement of sociologies of absences and emergences in this study evidence these epistemic insights, thereby evidencing an expansive post-abyssal (re)stor(y)ing of the citizen sciences. Through this research, I consider knowledge production as ‘commoning', towards the constitution of the common good. To date, most accounts of knowledge production within citizen science projects primarily focus on scientific processes of knowledge production and legitimation. Such accounts neglect the ecologies of diverse knowledges through which knowledge is being collaboratively produced, the forms of learning that occur, or the ways in which such ecologies are mobilised in response to specific socialecological risks. To better understand the ways in which citizen science projects build risk-responsive common knowledge, I bring a focus to the diversity of epistemic cultures convened, speaking to this gap. My primary research question is: How do the epistemic cultures within citizen science projects enable commoning in response to social-ecological risk? To begin, I establish a particular vantage point from which the remainder of the thesis is launched, one which centres as the primary interest of knowledge production, an interest in social-ecological justice and the constitution of the common good. From this vantage point, knowledge co-production and learning can be viewed as acts of commoning, which themselves constitute common goods. I draw on the work of Karin Knorr Cetina to conceptualise and frame notions of epistemic cultures and their epistemic features. Expanding notions of epistemic cultures from a post-abyssal perspective, I draw on the work of Bruno Latour and Boaventura de Sousa Santos. Latour’s distinctions between the production of ‘matters of fact’ and ‘matters of concern’ provide a way to challenge hegemonic systems of scientific knowledge production, while preserving the potential emergence of multiplicity in the context of evolving risk, thereby enabling a greater degree of situated reflexivity. Santos argues for the reclamation of all ways of knowing, including but not limited to scientific ways of knowing the world. He argues that other forms of knowledge are produced as nonexistent, and that they might be reclaimed through engaging sociologies of absences and emergences. Both authors enable a stronger analysis of knowledge production in terms of its ability to intervene into context in response to manifest risks. These three theoretical approaches are convened into an analytical framework for the study. To enact sociologies of absences and emergences, I engage two forms of immanent critique, complemented by an epistemic mapping of 50 South African citizen science projects, and an analysis of three illustrative case studies. The first critique is one of produced nonexistence, through which I consider three aspects of the general knowledge cultures within which the epistemic cultures of citizen science projects are situated. This critique makes evident the ways in which the ontological and related conceptual structures of hegemonic scientific knowledge production actively produce as nonexistent, other onto-epistemic contributions to knowledge production in response to social-ecological risks. The second critique reviews the field of peer-reviewed literature through a reading of presence and absence, with a focus on the articulation of epistemic cultures. Predictably, a key finding is that this form of scientific reporting primarily foregrounds legitimated scientifically processed knowledge, while once again producing as nonexistent, other forms of knowledges. However, there is evidence of increasing accounts of citizen science which recognise both a diversity of knowledge contributions, and epistemic, contributory and distributive justice issues as regards hegemonic forms of reporting. The epistemic mapping evidences a highly diversified field of citizen sciences, whose epistemic cultures are convened to produce distinct forms of scientifically-informed knowledges in response to diverse contexts, scales and notions of risk. The three illustrative case studies engage sociologies of absences and emergences, with particular focus on articulating the ecologies of knowledges evidenced in project documentation, including both official and unofficial accounts of epistemic activity. This analysis highlights the significant contributions of diverse forms of knowledges, including scientific, situated, embodied, governance, indigenous, spiritual and relational knowledges, and the ways in which these knowledge are convened to respond to specific configurations of risk. It once again highlights issues of epistemic, contributory and distributive justice, and makes evident the need for stronger integrity in processes of producing and reporting common knowledges. The case studies also illustrate the increased effectiveness of leveraging an ecology of knowledges (in contrast to a monoculture of scientific knowledge) in response to situated risks, including how such ecologies have a tendency to be generative and enable multiple forms of intervention into structures and applied contexts of intervention. In response to the collective research findings, a think-piece on rigour-as-integrity is offered as a contribution to commoning, in response to social-ecological risk. The piece draws together a postabyssal system of rigour intended to strengthen knowledge production in ways which actively centre forms of justice and commoning. ve potential in arts-based environmental learning with a focus on water pedagogy. The study took place over a period of four years, where approximately 40 school pupils between the ages of 10 and 17 years-old were engaged in participatory arts-based inquiries into water located across unequal neighbourhoods in Cape Town, South Africa. Educators, school learners, citizens and decision-makers hold different historical, cultural, political and spiritual perspectives on water. These play a role in shaping what is termed in this research the ‘hydro-social cycle’. Yet, due to dominant ideas of what counts as knowing and truth, educators in educational settings struggle to account for the complexity of water, limiting educational encounters to a partial knowing leading mostly to limited unimaginative framings of problems and solutions. My focus on transformative potential in learning is derived from a concern for how environmental education encounters and the sense-making they enable, are infused by socio-economic, political, and historical elements, specifically colonialism, capitalism, and white supremacist racism. The connections between the multiple layers of capitalist crisis and the ever-urgent environmental crisis are not adequately made in mainstream forms of water education. The research explores how arts-based pedagogy could enable a productive meeting of critical environmental education with ecological literacies. Within this positioning, transformative potential considers how educational engagements position questions about water within the social life of participants/learners and inform learning that leads to fuller and more nuanced greater knowledge. Theoretically, I work with an interrogation of critical education theory, underlaboured by critical realism which enabled me to rigorously consider how claims to knowing are shaped by their accompanying assumptions of what is real. Drawing on recent debates in critical education theory, I resist the notion of critique as ideology and engage instead in the craftsmanship of contextual and responsive inquiry practice. This has enabled me to articulate processes and relationships in water education encounters with meaningful understandings of the effects of simultaneous crises rooted in racial capitalism and environmental crisis. My methodological approach is arts-based educational research with a directive to reflect upon educational encounters in an integrated way. It includes two parts informing the facilitation and analysis of open-ended learning processes. One component was arts-based inquiry practice developed for exploring complexity, drawing on the thinking of Norris (2009, 2011) and Finley (2016, 2017). The second part holds reflective space for these encounters guided by the practice of pedagogical narration inspired by the Reggio Amelia approach, demonstrated by Pacini-Ketchabaw, Nxumalo, Kocher, Elliot and Sanchez (2014). Clarifying the intellectual work of a responsive educator-researcher, pedagogical narration brings multiple theoretical lenses into conversation with emergent dimensions of educational process. In practice, in order to transgress the dominance of colonial white supremacist knowledge frames of water, I needed to be curious, to be confounded, to expect the unexpected in the educational encounters with participants and this mirroring of practice was emulated by the participants as they followed their own questions about water in Mzansi (South Africa). In our work together we came up against assumptions we had previously not questioned as individuals. Together we explored the implications of this by, for example, questioning who is responsible for saving water. These explorations required bringing together science knowledge and everyday knowledge at multiple scales: the household, catchment, government and global. It required us to be critical of how language and images are mobilized in public communication and school curriculums; for example, representations of water are infused with history and power in a way that impacts how we know and teach about water. The transformative potential of this pedagogical space is generated through acts of creative expression which are seen as acts of absenting absence, for example exhibiting through play how water use in the household interconnects with gender and age relationships. As such, creative expression through multiple mediums or more-than-text enables a deeper understanding of water as well as openings for interdisciplinary engagement with learning about water. My research found that in bringing together the contributions of critical education and environmental education in practice, two shifts are needed: environmental educators need to view ecological literacy as inseparable from the social and political. The knowledge that is shared about water in the classroom has social and political implications. On the other hand, critical educators need to better locate justice concerns in the material and ecological world at scale. Arts-based inquiry, as a kind of scaffolding for pedagogical process, has the potential to enable these shifts by opening up fixed analytical frames. Making these shifts requires a reflective practice on the part of the educator to navigate the inherited blind spots in environmental learning and critical education, such as dualities. One way to do this is for the educator to identify absences, as articulated in the Critical Realist tradition, and consider how these absences might be absented. This differs from a simplistic process of critique in the possibilities it opens up for collaboration between different schools of thought rather than further polarisation and alienation between educators and knowledge keepers on social ecologies. These insights have relevance for many sites of environmental education practice, such as natural science lecturers, school teachers or community activists. It is knowledge-learning work emergent from and responsive to complex ecological crisis, which requires everyone to rethink and open up to new ways of being, seeing and doing around these issues. The transformative potential of this work is that the thinking and transforming at all scales can be catalysed and grounded through the arts based educational encounters with the participants. , Thesis (PhD) -- Faculty of Education, Education, 2022
- Full Text:
- Date Issued: 2022-04-08
- Authors: Vallabh, Priya
- Date: 2022-04-08
- Subjects: Science Citizen participation , Decolonization , Social epistemology , Hegemony , Common good , Traditional ecological knowledge , Ethnoscience
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/290671 , vital:56773 , DOI 10.21504/10962/290671
- Description: In this study I explore and explain transformatiThe citizen sciences convene complex and reflexive ecologies of knowledges in response to a range of social-ecological risks. Their epistemic cultures seem to be assembled in ways which increase potential mobilisation of the common knowledges being produced, thereby producing knowledges in forms that are more strongly aligned with a range of implementation strategies. However, much of such processes of knowledge production have been ‘cleaned out’ of official accounts through scientifically hegemonic systems of legitimation, deepening hegemonically-entrenched systems of epistemic, contributory and distributive injustices, and undermining the potential for stronger enactments of participatory and radical democracies. The engagement of sociologies of absences and emergences in this study evidence these epistemic insights, thereby evidencing an expansive post-abyssal (re)stor(y)ing of the citizen sciences. Through this research, I consider knowledge production as ‘commoning', towards the constitution of the common good. To date, most accounts of knowledge production within citizen science projects primarily focus on scientific processes of knowledge production and legitimation. Such accounts neglect the ecologies of diverse knowledges through which knowledge is being collaboratively produced, the forms of learning that occur, or the ways in which such ecologies are mobilised in response to specific socialecological risks. To better understand the ways in which citizen science projects build risk-responsive common knowledge, I bring a focus to the diversity of epistemic cultures convened, speaking to this gap. My primary research question is: How do the epistemic cultures within citizen science projects enable commoning in response to social-ecological risk? To begin, I establish a particular vantage point from which the remainder of the thesis is launched, one which centres as the primary interest of knowledge production, an interest in social-ecological justice and the constitution of the common good. From this vantage point, knowledge co-production and learning can be viewed as acts of commoning, which themselves constitute common goods. I draw on the work of Karin Knorr Cetina to conceptualise and frame notions of epistemic cultures and their epistemic features. Expanding notions of epistemic cultures from a post-abyssal perspective, I draw on the work of Bruno Latour and Boaventura de Sousa Santos. Latour’s distinctions between the production of ‘matters of fact’ and ‘matters of concern’ provide a way to challenge hegemonic systems of scientific knowledge production, while preserving the potential emergence of multiplicity in the context of evolving risk, thereby enabling a greater degree of situated reflexivity. Santos argues for the reclamation of all ways of knowing, including but not limited to scientific ways of knowing the world. He argues that other forms of knowledge are produced as nonexistent, and that they might be reclaimed through engaging sociologies of absences and emergences. Both authors enable a stronger analysis of knowledge production in terms of its ability to intervene into context in response to manifest risks. These three theoretical approaches are convened into an analytical framework for the study. To enact sociologies of absences and emergences, I engage two forms of immanent critique, complemented by an epistemic mapping of 50 South African citizen science projects, and an analysis of three illustrative case studies. The first critique is one of produced nonexistence, through which I consider three aspects of the general knowledge cultures within which the epistemic cultures of citizen science projects are situated. This critique makes evident the ways in which the ontological and related conceptual structures of hegemonic scientific knowledge production actively produce as nonexistent, other onto-epistemic contributions to knowledge production in response to social-ecological risks. The second critique reviews the field of peer-reviewed literature through a reading of presence and absence, with a focus on the articulation of epistemic cultures. Predictably, a key finding is that this form of scientific reporting primarily foregrounds legitimated scientifically processed knowledge, while once again producing as nonexistent, other forms of knowledges. However, there is evidence of increasing accounts of citizen science which recognise both a diversity of knowledge contributions, and epistemic, contributory and distributive justice issues as regards hegemonic forms of reporting. The epistemic mapping evidences a highly diversified field of citizen sciences, whose epistemic cultures are convened to produce distinct forms of scientifically-informed knowledges in response to diverse contexts, scales and notions of risk. The three illustrative case studies engage sociologies of absences and emergences, with particular focus on articulating the ecologies of knowledges evidenced in project documentation, including both official and unofficial accounts of epistemic activity. This analysis highlights the significant contributions of diverse forms of knowledges, including scientific, situated, embodied, governance, indigenous, spiritual and relational knowledges, and the ways in which these knowledge are convened to respond to specific configurations of risk. It once again highlights issues of epistemic, contributory and distributive justice, and makes evident the need for stronger integrity in processes of producing and reporting common knowledges. The case studies also illustrate the increased effectiveness of leveraging an ecology of knowledges (in contrast to a monoculture of scientific knowledge) in response to situated risks, including how such ecologies have a tendency to be generative and enable multiple forms of intervention into structures and applied contexts of intervention. In response to the collective research findings, a think-piece on rigour-as-integrity is offered as a contribution to commoning, in response to social-ecological risk. The piece draws together a postabyssal system of rigour intended to strengthen knowledge production in ways which actively centre forms of justice and commoning. ve potential in arts-based environmental learning with a focus on water pedagogy. The study took place over a period of four years, where approximately 40 school pupils between the ages of 10 and 17 years-old were engaged in participatory arts-based inquiries into water located across unequal neighbourhoods in Cape Town, South Africa. Educators, school learners, citizens and decision-makers hold different historical, cultural, political and spiritual perspectives on water. These play a role in shaping what is termed in this research the ‘hydro-social cycle’. Yet, due to dominant ideas of what counts as knowing and truth, educators in educational settings struggle to account for the complexity of water, limiting educational encounters to a partial knowing leading mostly to limited unimaginative framings of problems and solutions. My focus on transformative potential in learning is derived from a concern for how environmental education encounters and the sense-making they enable, are infused by socio-economic, political, and historical elements, specifically colonialism, capitalism, and white supremacist racism. The connections between the multiple layers of capitalist crisis and the ever-urgent environmental crisis are not adequately made in mainstream forms of water education. The research explores how arts-based pedagogy could enable a productive meeting of critical environmental education with ecological literacies. Within this positioning, transformative potential considers how educational engagements position questions about water within the social life of participants/learners and inform learning that leads to fuller and more nuanced greater knowledge. Theoretically, I work with an interrogation of critical education theory, underlaboured by critical realism which enabled me to rigorously consider how claims to knowing are shaped by their accompanying assumptions of what is real. Drawing on recent debates in critical education theory, I resist the notion of critique as ideology and engage instead in the craftsmanship of contextual and responsive inquiry practice. This has enabled me to articulate processes and relationships in water education encounters with meaningful understandings of the effects of simultaneous crises rooted in racial capitalism and environmental crisis. My methodological approach is arts-based educational research with a directive to reflect upon educational encounters in an integrated way. It includes two parts informing the facilitation and analysis of open-ended learning processes. One component was arts-based inquiry practice developed for exploring complexity, drawing on the thinking of Norris (2009, 2011) and Finley (2016, 2017). The second part holds reflective space for these encounters guided by the practice of pedagogical narration inspired by the Reggio Amelia approach, demonstrated by Pacini-Ketchabaw, Nxumalo, Kocher, Elliot and Sanchez (2014). Clarifying the intellectual work of a responsive educator-researcher, pedagogical narration brings multiple theoretical lenses into conversation with emergent dimensions of educational process. In practice, in order to transgress the dominance of colonial white supremacist knowledge frames of water, I needed to be curious, to be confounded, to expect the unexpected in the educational encounters with participants and this mirroring of practice was emulated by the participants as they followed their own questions about water in Mzansi (South Africa). In our work together we came up against assumptions we had previously not questioned as individuals. Together we explored the implications of this by, for example, questioning who is responsible for saving water. These explorations required bringing together science knowledge and everyday knowledge at multiple scales: the household, catchment, government and global. It required us to be critical of how language and images are mobilized in public communication and school curriculums; for example, representations of water are infused with history and power in a way that impacts how we know and teach about water. The transformative potential of this pedagogical space is generated through acts of creative expression which are seen as acts of absenting absence, for example exhibiting through play how water use in the household interconnects with gender and age relationships. As such, creative expression through multiple mediums or more-than-text enables a deeper understanding of water as well as openings for interdisciplinary engagement with learning about water. My research found that in bringing together the contributions of critical education and environmental education in practice, two shifts are needed: environmental educators need to view ecological literacy as inseparable from the social and political. The knowledge that is shared about water in the classroom has social and political implications. On the other hand, critical educators need to better locate justice concerns in the material and ecological world at scale. Arts-based inquiry, as a kind of scaffolding for pedagogical process, has the potential to enable these shifts by opening up fixed analytical frames. Making these shifts requires a reflective practice on the part of the educator to navigate the inherited blind spots in environmental learning and critical education, such as dualities. One way to do this is for the educator to identify absences, as articulated in the Critical Realist tradition, and consider how these absences might be absented. This differs from a simplistic process of critique in the possibilities it opens up for collaboration between different schools of thought rather than further polarisation and alienation between educators and knowledge keepers on social ecologies. These insights have relevance for many sites of environmental education practice, such as natural science lecturers, school teachers or community activists. It is knowledge-learning work emergent from and responsive to complex ecological crisis, which requires everyone to rethink and open up to new ways of being, seeing and doing around these issues. The transformative potential of this work is that the thinking and transforming at all scales can be catalysed and grounded through the arts based educational encounters with the participants. , Thesis (PhD) -- Faculty of Education, Education, 2022
- Full Text:
- Date Issued: 2022-04-08
Multilayer perceptron artificial neural network for the prediction of heating value of municipal solid waste
- Authors: Stephen Akinlabi
- Date: 2019
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/11260/3757 , vital:43943
- Full Text:
- Authors: Stephen Akinlabi
- Date: 2019
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/11260/3757 , vital:43943
- Full Text:
Studies in the thiophenol mediated substitution and reductive dehalogenation of 3 bromoacetylcoumarins
- Authors: Magwenzi, Faith N
- Date: 2017
- Subjects: 3-bromoacetylcoumarins , Coumarins , Halogens -- Decontamination , Thiols , Plasmodium falciparum , Malaria -- Chemotherapy
- Language: English
- Type: Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/45769 , vital:25546
- Description: A previous study conducted by our group identified indolyl-3-ethanone-a-thioethers (2.1a and 2.1b) as non-toxic, nanomolar, in vitro inhibitors of Plasmodium falciparum. Since the coumarin scaffold is associated with numerous biologically active compounds including antiprotozoal, anti-viral, anti-bacterial, and anti-inflammatory agents we were prompted to investigate coumaryl-3-ethanone-a-thioethers (2.1c) inspired by the activity of 2.1a and 2.1b against P. falciparum. We proposed a three-step synthesis of our target compounds 2.1c. The first step involved the Knoevenagel synthesis of 3-acetyl coumarins (2.3.1a - e) followed by a selective a-bromination to yield 3-bromoacetyl coumarin (2.2a). The final proposed step involved the nucleophilic displacement of the bromine by appropriately substituted thiophenols in either the presence or absence of base (K2CO3). Our initial findings revealed an unexpected major reductive dehalogenation of 2.2a into 2.3.1a. Further investigation revealed a close relationship between the electron withdrawing or donating nature of the thiophenol substituents and the relative formation of nucleophilic substitution or reductive dehalogenation products. Desired thioether products were obtained in higher yields when thiophenol was substituted with electron donating groups i.e. more nucleophilic thiophenols, while conversely, electron withdrawing substituents (i.e. lowered nucleophilicity) resulted in an increase of reductive dehalogenation. Furthermore, these results were consistent when experiments were conducted using either 2 or 1.2 equivalents of thiophenols which was an important observation in the context of two previous studies, by Oki et. al. and Israel et. al. Oki proposed that dehalogenation of a-chloro carbonyls occurs via sequential nucleophilic displacement of a-thioethers, while the study of Israel concluded that the dehalogenation of a-iodo carbonyls occurred in a single discreet step. Finally, in an effort to enhance nucleophilic substitution through the addition of K2CO3, we observed a Robinson annulation resulting in previously undescribed C-8 thiophenol functionalised dibenzo[b,d]pyran-6-ones (3.4a - e). In the introduction to this thesis, we briefly summarise the utility of coumarins in medicinal chemistry and related fields. Chapter two describes the rationalisation of our original research question and a retrosynthetic analysis of our desired compounds, followed by an initial description of the unexpected reductive dehalogenation. Chapter 3, begins with a brief review of reductive dehalogenation of a-halocarbonyls, and is followed by an analysis and discussion of our results in the context of the studies by Israel et. al. and Oki et. al.
- Full Text:
- Date Issued: 2017
- Authors: Magwenzi, Faith N
- Date: 2017
- Subjects: 3-bromoacetylcoumarins , Coumarins , Halogens -- Decontamination , Thiols , Plasmodium falciparum , Malaria -- Chemotherapy
- Language: English
- Type: Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/45769 , vital:25546
- Description: A previous study conducted by our group identified indolyl-3-ethanone-a-thioethers (2.1a and 2.1b) as non-toxic, nanomolar, in vitro inhibitors of Plasmodium falciparum. Since the coumarin scaffold is associated with numerous biologically active compounds including antiprotozoal, anti-viral, anti-bacterial, and anti-inflammatory agents we were prompted to investigate coumaryl-3-ethanone-a-thioethers (2.1c) inspired by the activity of 2.1a and 2.1b against P. falciparum. We proposed a three-step synthesis of our target compounds 2.1c. The first step involved the Knoevenagel synthesis of 3-acetyl coumarins (2.3.1a - e) followed by a selective a-bromination to yield 3-bromoacetyl coumarin (2.2a). The final proposed step involved the nucleophilic displacement of the bromine by appropriately substituted thiophenols in either the presence or absence of base (K2CO3). Our initial findings revealed an unexpected major reductive dehalogenation of 2.2a into 2.3.1a. Further investigation revealed a close relationship between the electron withdrawing or donating nature of the thiophenol substituents and the relative formation of nucleophilic substitution or reductive dehalogenation products. Desired thioether products were obtained in higher yields when thiophenol was substituted with electron donating groups i.e. more nucleophilic thiophenols, while conversely, electron withdrawing substituents (i.e. lowered nucleophilicity) resulted in an increase of reductive dehalogenation. Furthermore, these results were consistent when experiments were conducted using either 2 or 1.2 equivalents of thiophenols which was an important observation in the context of two previous studies, by Oki et. al. and Israel et. al. Oki proposed that dehalogenation of a-chloro carbonyls occurs via sequential nucleophilic displacement of a-thioethers, while the study of Israel concluded that the dehalogenation of a-iodo carbonyls occurred in a single discreet step. Finally, in an effort to enhance nucleophilic substitution through the addition of K2CO3, we observed a Robinson annulation resulting in previously undescribed C-8 thiophenol functionalised dibenzo[b,d]pyran-6-ones (3.4a - e). In the introduction to this thesis, we briefly summarise the utility of coumarins in medicinal chemistry and related fields. Chapter two describes the rationalisation of our original research question and a retrosynthetic analysis of our desired compounds, followed by an initial description of the unexpected reductive dehalogenation. Chapter 3, begins with a brief review of reductive dehalogenation of a-halocarbonyls, and is followed by an analysis and discussion of our results in the context of the studies by Israel et. al. and Oki et. al.
- Full Text:
- Date Issued: 2017
The supervisor’s tale: postgraduate supervisors’ experiences in a changing Higher Education environment
- Authors: Searle, Ruth Lesley
- Date: 2015
- Subjects: Graduate students -- Supervision of -- South Africa , Education, Higher -- South Africa , Educational change -- South Africa , Archer, Margaret Scotford -- Political and social views , Critical realism , Knowledge, Sociology of , Dissertations, Academic , Faculty advisors -- South Africa , Education -- Study and teaching (Graduate) -- South Africa , Universities and colleges -- Graduate work
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1331 , http://hdl.handle.net/10962/d1019952
- Description: The environment in which higher education institutions operate is changing, and these changes are impacting on all aspects of higher education, including postgraduate levels. Changes wrought by globalisation, heralded by rapid advances in technology have inaugurated a new era in which there are long term consequences for higher education. The shift towards more quantitative and measurable "outputs" signifies a fundamental change in the educational ethos in institutions. Effectiveness is now judged primarily on numbers of graduates and publications rather than on other aspects. The drive is to produce a highly educated population, especially through increasing postgraduates who can drive national innovation and improve national economies. This affects academics in a range of ways, not least in the ways in which they engage in teaching, what they are willing to do and how they do it. Such changes influence the kinds of research done, the structures and funding which support research, and thus naturally shapes the kinds of postgraduate programmes and teaching that occurs. This study, situated in the field of Higher Education Studies, adopting a critical realist stance and drawing on the social theory of Margaret Archer and the concepts of expert and novice, explores the experiences of postgraduate supervisors from one South African institution across a range of disciplines. Individual experiences at the level of the Empirical and embodied in practice at the level of the Actual allow for the identification of possible mechanisms at the level of the Real which structure the sector. The research design then allows for an exploration across mezzo, macro and micro levels. Individuals outline their own particular situations, identifying a number of elements which enabled or constrained them and how, in exercising their agency, they develop their strategies for supervision drawing on a range of different resources that they identify and that may be available to them. Student characteristics, discipline status and placement, funding, and the emergent policy environment are all identified as influencing their practice. In some instances supervisors recognise the broader influences on the system that involve them in their undertaking, noting the international trends. Through their narratives and the discourses they engage a number of contradictions that have developed in the system with growing neo-liberal trends and vocationalism highlighting tensions between academic freedom and autonomy, and demands for productivity, efficiency and compliance, and between an educational focus and a training bias in particular along with others. Especially notable is how this contributes to the current ideologies surrounding knowledge and knowledge production. Their individual interests and concerns, and emergent academic identities as they take shape over time, also modifies the process and how individual supervisors influence their own environments in agentic moves becomes apparent. Whilst often individuals highlight the lack of support especially in the early phases of supervision, the emergent policy-constrained environment is also seen as curtailing possibilities and especially in limiting the possibilities for the exercise of agency. Whilst the study has some limitations in the range and number of respondents nevertheless the data provided rich evidence of how individual supervisors are affected, and how they respond in varied conditions. What is highlighted through these experiences are ways pressures are increasing for both supervisors and students and changing how they engage. Concerns in particular are raised about the growing functional and instrumental nature of the process with an emphasis on the effects on the kinds of researchers being developed and the knowledge that is therefore being produced. As costs increase for academics through the environments developed and with the varied roles they take on so they become more selective and reluctant to expand the role. This research has provided insights into ideas, beliefs and values relating to the postgraduate sector and to the process of postgraduate supervision and how it occurs. This includes the structures and cultural conditions that enable or constrain practitioners as they develop in the role in this particular institution. It has explored some of the ways that mechanisms at international, national and institutional levels shape the role and practices of supervisors. The effects of mechanisms are in no way a given or simply understood. In this way the research may contribute to more emancipatory knowledge which could be used in planning and deciding on emergent policies and practices which might create a more supportive and creative postgraduate environment.
- Full Text:
- Date Issued: 2015
- Authors: Searle, Ruth Lesley
- Date: 2015
- Subjects: Graduate students -- Supervision of -- South Africa , Education, Higher -- South Africa , Educational change -- South Africa , Archer, Margaret Scotford -- Political and social views , Critical realism , Knowledge, Sociology of , Dissertations, Academic , Faculty advisors -- South Africa , Education -- Study and teaching (Graduate) -- South Africa , Universities and colleges -- Graduate work
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1331 , http://hdl.handle.net/10962/d1019952
- Description: The environment in which higher education institutions operate is changing, and these changes are impacting on all aspects of higher education, including postgraduate levels. Changes wrought by globalisation, heralded by rapid advances in technology have inaugurated a new era in which there are long term consequences for higher education. The shift towards more quantitative and measurable "outputs" signifies a fundamental change in the educational ethos in institutions. Effectiveness is now judged primarily on numbers of graduates and publications rather than on other aspects. The drive is to produce a highly educated population, especially through increasing postgraduates who can drive national innovation and improve national economies. This affects academics in a range of ways, not least in the ways in which they engage in teaching, what they are willing to do and how they do it. Such changes influence the kinds of research done, the structures and funding which support research, and thus naturally shapes the kinds of postgraduate programmes and teaching that occurs. This study, situated in the field of Higher Education Studies, adopting a critical realist stance and drawing on the social theory of Margaret Archer and the concepts of expert and novice, explores the experiences of postgraduate supervisors from one South African institution across a range of disciplines. Individual experiences at the level of the Empirical and embodied in practice at the level of the Actual allow for the identification of possible mechanisms at the level of the Real which structure the sector. The research design then allows for an exploration across mezzo, macro and micro levels. Individuals outline their own particular situations, identifying a number of elements which enabled or constrained them and how, in exercising their agency, they develop their strategies for supervision drawing on a range of different resources that they identify and that may be available to them. Student characteristics, discipline status and placement, funding, and the emergent policy environment are all identified as influencing their practice. In some instances supervisors recognise the broader influences on the system that involve them in their undertaking, noting the international trends. Through their narratives and the discourses they engage a number of contradictions that have developed in the system with growing neo-liberal trends and vocationalism highlighting tensions between academic freedom and autonomy, and demands for productivity, efficiency and compliance, and between an educational focus and a training bias in particular along with others. Especially notable is how this contributes to the current ideologies surrounding knowledge and knowledge production. Their individual interests and concerns, and emergent academic identities as they take shape over time, also modifies the process and how individual supervisors influence their own environments in agentic moves becomes apparent. Whilst often individuals highlight the lack of support especially in the early phases of supervision, the emergent policy-constrained environment is also seen as curtailing possibilities and especially in limiting the possibilities for the exercise of agency. Whilst the study has some limitations in the range and number of respondents nevertheless the data provided rich evidence of how individual supervisors are affected, and how they respond in varied conditions. What is highlighted through these experiences are ways pressures are increasing for both supervisors and students and changing how they engage. Concerns in particular are raised about the growing functional and instrumental nature of the process with an emphasis on the effects on the kinds of researchers being developed and the knowledge that is therefore being produced. As costs increase for academics through the environments developed and with the varied roles they take on so they become more selective and reluctant to expand the role. This research has provided insights into ideas, beliefs and values relating to the postgraduate sector and to the process of postgraduate supervision and how it occurs. This includes the structures and cultural conditions that enable or constrain practitioners as they develop in the role in this particular institution. It has explored some of the ways that mechanisms at international, national and institutional levels shape the role and practices of supervisors. The effects of mechanisms are in no way a given or simply understood. In this way the research may contribute to more emancipatory knowledge which could be used in planning and deciding on emergent policies and practices which might create a more supportive and creative postgraduate environment.
- Full Text:
- Date Issued: 2015
Assessing invasive alien aquatic plant species, phytoremediation effects using biological indicators in the Swartkops River system
- Authors: Tshithukhe, Getrude
- Date: 2020
- Subjects: Aquatic weeds -- Biological control -- South Africa -- Eastern Cape , Alien plants -- Biological control -- South Africa -- Eastern Cape , Phytoremediation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/167665 , vital:41501
- Description: Pollution effluents in freshwater ecosystems are becoming increasingly ubiquitous as a result of cumulative anthropogenic activities, such as wastewater treatments works, and industrial, agricultural and mining activities. These activities are more noticeable in urban river atchments where there is greater human population densities and industrial developments. The ecological effects of anthropogenic activities on freshwater ecosystems include: excessive deposition of contaminants such as nutrients, pharmaceuticals, microplastics and other chemicals, which change physicochemical properties, causing a decline in aquatic biodiversity. These effects, impact negatively on the resilience of freshwater, making the systems vulnerable to invasion by alien aquatic plants. Ultimately, the loss of local biodiversity associated with the invasive alien aquatic plants (IAAP) results in a loss of some ecosystem goods and services. The Swartkops River system, Eastern Cape Province, drains most of the neighbouring formal and informal settlements, agricultural lands and industries, and hence is exposed to water pollution from human activities along the river catchment. Various water quality assessments are needed to evaluate the extent of pollutants and their impacts on the river ecosystem. Phytoremediation is one approach employed internationally for removing harmful nutrients and chemicals in freshwater ecosystems. Most studies measure the success of phytoremediation through measuring the reduction of contaminants in water or soil chemistry in mesocosm settings, which may not take into account all the important environmental factors that exist in the field. The present study assesses the phytoremediation potential of Pontederia (Eichhornia) crassipes and Salvinia molesta by evaluating water and sediment chemistry, periphyton and aquatic macroinvertebrate community recovery along seven field sites (excluding IAAP species mats sites) located upstream and downstream IAAP species mats on the Swartkops River between April and September 2018. Water and sediment samples were collected once monthly on ten seven field sites, including the IAAP species mat sites. Periphyton and aquatic macroinvertebrates were collected on seven sites, excluding the IAAP mat sites. Pontederia crassipes and S. molesta infestation in Swartkops River showed positive phytoremediation results and improved some water and sediment chemistry in the downstream treatments as compared to upstream treatments. Although there were some fluctuations with some variables, important water and sediment chemistry were reduced downstream. By contrast, biological assessment results did not show any response to the presence of IAAP species and phytoremediation. Periphyton and aquatic macroinvertebrates diversity and community assemblages were more influenced by water quality. Although IAAP species did provide improvement in water and sediments chemistry, multiple effluent point and non-point sources in Swartkops outpaced phytoremediation. Taxa evenness and relative taxa abundance showed significant differences between the upstream and downstream sites, however taxa richness and Shannon’s diversity showed no significant differences, indicating no relative recovery in biodiversity for either periphyton or aquatic macroinvertebrates. Similarly, the upstream and downstream sites showed similar periphyton and aquatic macroinvertebrates assemblages structure, all dominated by pollution tolerant taxa, thus indicating no functional diversity improvement down river; because of improvement in water chemistry downstream sites, it was expected that periphyton and aquatic macroinvertebrates assemblage structure would also improve at these downstream sites.It is possible that the phytoremediation process is outpaced by effluent discharges, given the multiple sources and distance between upstream and downstream mat sites. The study showed phytoremediation potential but the results were not indicated by biological indicators. A replica study conducted on a moderately disturbed river system is recommended to measure the success and recovery of biological indicators and assemblage composition following IAAP species phytoremediation; a moderately disturbed river compared to a largely disturbed river will broaden findings and look at differences for a wider application of phytoremediation.
- Full Text:
- Date Issued: 2020
- Authors: Tshithukhe, Getrude
- Date: 2020
- Subjects: Aquatic weeds -- Biological control -- South Africa -- Eastern Cape , Alien plants -- Biological control -- South Africa -- Eastern Cape , Phytoremediation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/167665 , vital:41501
- Description: Pollution effluents in freshwater ecosystems are becoming increasingly ubiquitous as a result of cumulative anthropogenic activities, such as wastewater treatments works, and industrial, agricultural and mining activities. These activities are more noticeable in urban river atchments where there is greater human population densities and industrial developments. The ecological effects of anthropogenic activities on freshwater ecosystems include: excessive deposition of contaminants such as nutrients, pharmaceuticals, microplastics and other chemicals, which change physicochemical properties, causing a decline in aquatic biodiversity. These effects, impact negatively on the resilience of freshwater, making the systems vulnerable to invasion by alien aquatic plants. Ultimately, the loss of local biodiversity associated with the invasive alien aquatic plants (IAAP) results in a loss of some ecosystem goods and services. The Swartkops River system, Eastern Cape Province, drains most of the neighbouring formal and informal settlements, agricultural lands and industries, and hence is exposed to water pollution from human activities along the river catchment. Various water quality assessments are needed to evaluate the extent of pollutants and their impacts on the river ecosystem. Phytoremediation is one approach employed internationally for removing harmful nutrients and chemicals in freshwater ecosystems. Most studies measure the success of phytoremediation through measuring the reduction of contaminants in water or soil chemistry in mesocosm settings, which may not take into account all the important environmental factors that exist in the field. The present study assesses the phytoremediation potential of Pontederia (Eichhornia) crassipes and Salvinia molesta by evaluating water and sediment chemistry, periphyton and aquatic macroinvertebrate community recovery along seven field sites (excluding IAAP species mats sites) located upstream and downstream IAAP species mats on the Swartkops River between April and September 2018. Water and sediment samples were collected once monthly on ten seven field sites, including the IAAP species mat sites. Periphyton and aquatic macroinvertebrates were collected on seven sites, excluding the IAAP mat sites. Pontederia crassipes and S. molesta infestation in Swartkops River showed positive phytoremediation results and improved some water and sediment chemistry in the downstream treatments as compared to upstream treatments. Although there were some fluctuations with some variables, important water and sediment chemistry were reduced downstream. By contrast, biological assessment results did not show any response to the presence of IAAP species and phytoremediation. Periphyton and aquatic macroinvertebrates diversity and community assemblages were more influenced by water quality. Although IAAP species did provide improvement in water and sediments chemistry, multiple effluent point and non-point sources in Swartkops outpaced phytoremediation. Taxa evenness and relative taxa abundance showed significant differences between the upstream and downstream sites, however taxa richness and Shannon’s diversity showed no significant differences, indicating no relative recovery in biodiversity for either periphyton or aquatic macroinvertebrates. Similarly, the upstream and downstream sites showed similar periphyton and aquatic macroinvertebrates assemblages structure, all dominated by pollution tolerant taxa, thus indicating no functional diversity improvement down river; because of improvement in water chemistry downstream sites, it was expected that periphyton and aquatic macroinvertebrates assemblage structure would also improve at these downstream sites.It is possible that the phytoremediation process is outpaced by effluent discharges, given the multiple sources and distance between upstream and downstream mat sites. The study showed phytoremediation potential but the results were not indicated by biological indicators. A replica study conducted on a moderately disturbed river system is recommended to measure the success and recovery of biological indicators and assemblage composition following IAAP species phytoremediation; a moderately disturbed river compared to a largely disturbed river will broaden findings and look at differences for a wider application of phytoremediation.
- Full Text:
- Date Issued: 2020
Electrodeposited Benzothiazole Phthalocyanines for Corrosion Inhibition of Aluminium in Acidic Medium
- Nnaji, Nnaemeka, Nwaji, Njemuwa, Nyokong, Tebello
- Authors: Nnaji, Nnaemeka , Nwaji, Njemuwa , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186112 , vital:44464 , xlink:href="https://doi.org/10.1155/2020/8892559"
- Description: Tetrakis[(benzo[d]thiazol-2-yl-thio) phthalocyaninato] gallium(III)chloride (1) and tetrakis[(benzo[d]thiazol-2ylphenoxy) phthalocyaninato] gallium(III)chloride (2) were successfully electrodeposited onto aluminium for corrosion retardation in 1.0 M hydrochloric acid solution. The aim of this study was to compare the corrosion resistance of electrodeposited metallated phthalocyanines. Scanning electron microscopy, X-ray diffraction, electrochemical impedance spectroscopy (EIS), and polarization confirmed the aluminium corrosion inhibition potentials of complexes 1 and 2. EIS and polarization techniques showed that complex 2 performed better than complex 1, with values from EIS measurements of 82% for 1 and 86% for 2 in 1.0 M hydrochloric acid solution. The importance of electrodeposition in industries and a dearth of research on the use of electrodeposited metallated phthalocyanines necessitated this study, and results show that coatings formed by electrodeposition of 1 and 2 onto aluminium reduced its susceptibility to corrosion attack.
- Full Text:
- Date Issued: 2020
- Authors: Nnaji, Nnaemeka , Nwaji, Njemuwa , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186112 , vital:44464 , xlink:href="https://doi.org/10.1155/2020/8892559"
- Description: Tetrakis[(benzo[d]thiazol-2-yl-thio) phthalocyaninato] gallium(III)chloride (1) and tetrakis[(benzo[d]thiazol-2ylphenoxy) phthalocyaninato] gallium(III)chloride (2) were successfully electrodeposited onto aluminium for corrosion retardation in 1.0 M hydrochloric acid solution. The aim of this study was to compare the corrosion resistance of electrodeposited metallated phthalocyanines. Scanning electron microscopy, X-ray diffraction, electrochemical impedance spectroscopy (EIS), and polarization confirmed the aluminium corrosion inhibition potentials of complexes 1 and 2. EIS and polarization techniques showed that complex 2 performed better than complex 1, with values from EIS measurements of 82% for 1 and 86% for 2 in 1.0 M hydrochloric acid solution. The importance of electrodeposition in industries and a dearth of research on the use of electrodeposited metallated phthalocyanines necessitated this study, and results show that coatings formed by electrodeposition of 1 and 2 onto aluminium reduced its susceptibility to corrosion attack.
- Full Text:
- Date Issued: 2020
Changes in chemical composition of essential oils from leaves of different Lantana camara L. (Verbenaceae) varieties after feeding by the introduced biological control agent, Falconia intermedia Distant (Hemiptera: Miridae)
- Ngxande-Koza, S W, Heshula, L U P, Hill, Martin P
- Authors: Ngxande-Koza, S W , Heshula, L U P , Hill, Martin P
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59834 , vital:27664 , https://doi.org/10.4001/003.025.0462
- Description: Lantana camara L. (Verbenaceae) is one of the most problematic plant invaders in South Africa and has been targeted for biological control for over 50 years. Essential oil constituents which often change in response to insect herbivory are reported to play a crucial role in plant-insect interactions. However, nothing is known about the chemical profiles of essential oils of L. camara varieties in South Africa and how this changes under herbivory. Therefore, essential oils were collected using hydrodistillation from undamaged and insect-damaged leaves of four L. camara varieties and analysed using gas chromatography-mass spectrometry to elucidate their chemical profiles. A total of 163 compounds were identified from the undamaged leaves of the various L. camara varieties. Feeding by the biocontrol agent Falconia intermedia Distant (Hemiptera: Miridae) resulted in changes in the quality and quantity of chemical constituents of the essential oils. Only 75 compounds were identified from the insect-damaged leaves of L. camara varieties. Terpenes were the major components across the varieties, while caryophyllene, hexane, naphthalene, copaene and a-caryophyllene were common in all the varieties tested from both undamaged and insect-damaged leaves. Results from this study indicated the chemical distinctiveness of the Whitney Farm variety from other varieties. The changes in chemical concentrations indicated that feeding by the mirid on L. camara varieties causes an induction by either reducing or increasing the chemical concentrations. These inductions following the feeding by F. intermedia could be having a negative impact on the success of biological control against L. camara varieties. However, the focus of this paper is to report on the chemical baseline of L. camara varieties. Hence, comparisons of chemical compound concentrations of L. camara essential oils tested and the feeding-induced changes with respect to their quality and quantity are discussed.
- Full Text:
- Date Issued: 2017
- Authors: Ngxande-Koza, S W , Heshula, L U P , Hill, Martin P
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59834 , vital:27664 , https://doi.org/10.4001/003.025.0462
- Description: Lantana camara L. (Verbenaceae) is one of the most problematic plant invaders in South Africa and has been targeted for biological control for over 50 years. Essential oil constituents which often change in response to insect herbivory are reported to play a crucial role in plant-insect interactions. However, nothing is known about the chemical profiles of essential oils of L. camara varieties in South Africa and how this changes under herbivory. Therefore, essential oils were collected using hydrodistillation from undamaged and insect-damaged leaves of four L. camara varieties and analysed using gas chromatography-mass spectrometry to elucidate their chemical profiles. A total of 163 compounds were identified from the undamaged leaves of the various L. camara varieties. Feeding by the biocontrol agent Falconia intermedia Distant (Hemiptera: Miridae) resulted in changes in the quality and quantity of chemical constituents of the essential oils. Only 75 compounds were identified from the insect-damaged leaves of L. camara varieties. Terpenes were the major components across the varieties, while caryophyllene, hexane, naphthalene, copaene and a-caryophyllene were common in all the varieties tested from both undamaged and insect-damaged leaves. Results from this study indicated the chemical distinctiveness of the Whitney Farm variety from other varieties. The changes in chemical concentrations indicated that feeding by the mirid on L. camara varieties causes an induction by either reducing or increasing the chemical concentrations. These inductions following the feeding by F. intermedia could be having a negative impact on the success of biological control against L. camara varieties. However, the focus of this paper is to report on the chemical baseline of L. camara varieties. Hence, comparisons of chemical compound concentrations of L. camara essential oils tested and the feeding-induced changes with respect to their quality and quantity are discussed.
- Full Text:
- Date Issued: 2017
In-vitroevaluation of bridelia ferruginea extract gold nanoparticles for the treatment of colon cancer
- Zosela, Itumeleng, Davids, Hajierah
- Authors: Zosela, Itumeleng , Davids, Hajierah
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54124 , vital:46311
- Description: Colorectal cancer (CRC) has become a health burden, being the third common cancer worldwide. Treatment of colorectal cancer is very important to manage the high prevalence rate of this disease. The available treatments for CRC have their drawbacks and side effects. Available treatments of colon cancer include surgery, chemotherapy, and radiation. Due to the side effects associated with these treatments, alternative treatments that pose less side effects are being developed worldwide. Nanotechnologies have gained global consideration due to their potential to improve the current standards and techniques for the diagnosis and treatment. The use of plants for synthesis of gold nanoparticles has opened a new venture of synthesizing environmentally friendly and cost-effective nanoparticles which possess great properties for CRC treatment. The aim of this study was to investigate the use of green synthesized AuNPs from Bridelia ferruginea for potential cancer treatment. In this work study gold nanoparticles were synthesized utilizing Bridelia ferruginea stem bark extract. The nanoparticles were characterized using UV–Vis spectroscopy, Dynamic Light Scattering (DLS), Fourier Transform Infrared Spectroscopy (FTIR) and High-Resolution Transmission Electron Microscopy (HRTEM). The in vitroanti cancer activity of the AuNPs was investigated using Presto Blue assay, cellular morphology, caspase 3/7 assay on the human colon cancer cell line at different times to assess the optimum time for cell death. The cellular uptake and localization of AuNPs was investigated using HRTEM to assess uptake and location of the AuNPs within the cell. Results obtained from this study showed that the AuNP synthesis from Bridellia ferrugenia was successful. The Presto Blue cell viability results showed that the AuNPs reduced cell viability (%) significantly (p<0.05) after 24 h. The optimum treatment time of HT-29 cells with AuNPs was determined to be 24 h. The apoptotic effects of the AuNPs were assessed using Cell Event reagent, and the results from this assay indicated that caspase 3/7 was activated with treatment with AuNPs which induced cell death via apoptosis. The HRTEM results indicated that there was no uptake of AuNP targeting in HT-29 therefore localization could not be determined. It can be concluded that the AuNPs synthesized from Bridellia ferrugenia have anti-cancer properties and are able to induce cell death through apoptosis. Furthermore, this study revealed that optimization of the AuNPs for cellular uptake is needed to further understand the interaction between the nanoparticles and the cells. This will provide more insight on how cellular death is induced by the nanoparticles. , Thesis (MSc) -- Faculty of Science, Department of Biochemistry and Microbiology (including Physiology), 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Zosela, Itumeleng , Davids, Hajierah
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54124 , vital:46311
- Description: Colorectal cancer (CRC) has become a health burden, being the third common cancer worldwide. Treatment of colorectal cancer is very important to manage the high prevalence rate of this disease. The available treatments for CRC have their drawbacks and side effects. Available treatments of colon cancer include surgery, chemotherapy, and radiation. Due to the side effects associated with these treatments, alternative treatments that pose less side effects are being developed worldwide. Nanotechnologies have gained global consideration due to their potential to improve the current standards and techniques for the diagnosis and treatment. The use of plants for synthesis of gold nanoparticles has opened a new venture of synthesizing environmentally friendly and cost-effective nanoparticles which possess great properties for CRC treatment. The aim of this study was to investigate the use of green synthesized AuNPs from Bridelia ferruginea for potential cancer treatment. In this work study gold nanoparticles were synthesized utilizing Bridelia ferruginea stem bark extract. The nanoparticles were characterized using UV–Vis spectroscopy, Dynamic Light Scattering (DLS), Fourier Transform Infrared Spectroscopy (FTIR) and High-Resolution Transmission Electron Microscopy (HRTEM). The in vitroanti cancer activity of the AuNPs was investigated using Presto Blue assay, cellular morphology, caspase 3/7 assay on the human colon cancer cell line at different times to assess the optimum time for cell death. The cellular uptake and localization of AuNPs was investigated using HRTEM to assess uptake and location of the AuNPs within the cell. Results obtained from this study showed that the AuNP synthesis from Bridellia ferrugenia was successful. The Presto Blue cell viability results showed that the AuNPs reduced cell viability (%) significantly (p<0.05) after 24 h. The optimum treatment time of HT-29 cells with AuNPs was determined to be 24 h. The apoptotic effects of the AuNPs were assessed using Cell Event reagent, and the results from this assay indicated that caspase 3/7 was activated with treatment with AuNPs which induced cell death via apoptosis. The HRTEM results indicated that there was no uptake of AuNP targeting in HT-29 therefore localization could not be determined. It can be concluded that the AuNPs synthesized from Bridellia ferrugenia have anti-cancer properties and are able to induce cell death through apoptosis. Furthermore, this study revealed that optimization of the AuNPs for cellular uptake is needed to further understand the interaction between the nanoparticles and the cells. This will provide more insight on how cellular death is induced by the nanoparticles. , Thesis (MSc) -- Faculty of Science, Department of Biochemistry and Microbiology (including Physiology), 2021
- Full Text:
- Date Issued: 2021-12
From human to human(e): an educator's reflexive narrative journeying
- Authors: Rajoo, Neeranjini
- Date: 2013
- Subjects: Elementary school teachers -- South Africa , Poor -- South Africa , Humanity -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9588 , http://hdl.handle.net/10948/d1021001
- Description: From human to human(e) is an exploration of ways of coming to understand what it means to be(come) human and to belong (Vanier, 2003) while living and working as an educator in a disadvantaged community. In this sense, the purpose of this dissertation is the exploration of understanding what it might mean to be a ‘Foundation Phase’ (Primary/Elementary School) educator in a context of constructed poverty and disadvantage (Swanson 2004), thereby contributing to the field of education in this area, whilst embracing a practice of freedom and fostering apertures of hope and transcendence. This reflexive, rhizomatic narrative journeying (ibid) attempts to reach out to humanity via an interdisciplinary and arts-based approach that attempts to address concerns of inequity and pedagogical in-access and evokes the spiritual, emotive and philosophical in drawing attention to the ethical irresponsibility and socio-spiritual repercussions of ignoring social disadvantage in education. It includes inherences and impressions of humaneness in education. It seeks both introspection and insight into what ‘the human condition’ might mean to a just and robust education of children. In this sense, it is a personal inquiry as reflexive narrative journeying (ibid) based on twenty seven years of teaching in a primary school in a vulnerable and economically-impoverished community in the province of KwaZulu Natal in South Africa. As a writing-as-inquiry journeying, I engage with ‘critical rhizomatic narrative’ methodology (Swanson, 2004) as it resonates with the explorations of lived experiences that pertain to emotions, feelings, values and spirituality and because it enables a process of seeking what it might mean to be(come) human(e). This study is a philosophical rhizomatic narrative rendering which is an approach to(wards) understandings of personal growth and spirituality through understanding the various emergent journeys of life and the meanings that we can elicit from them to become more human and thus more humane.
- Full Text:
- Date Issued: 2013
- Authors: Rajoo, Neeranjini
- Date: 2013
- Subjects: Elementary school teachers -- South Africa , Poor -- South Africa , Humanity -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9588 , http://hdl.handle.net/10948/d1021001
- Description: From human to human(e) is an exploration of ways of coming to understand what it means to be(come) human and to belong (Vanier, 2003) while living and working as an educator in a disadvantaged community. In this sense, the purpose of this dissertation is the exploration of understanding what it might mean to be a ‘Foundation Phase’ (Primary/Elementary School) educator in a context of constructed poverty and disadvantage (Swanson 2004), thereby contributing to the field of education in this area, whilst embracing a practice of freedom and fostering apertures of hope and transcendence. This reflexive, rhizomatic narrative journeying (ibid) attempts to reach out to humanity via an interdisciplinary and arts-based approach that attempts to address concerns of inequity and pedagogical in-access and evokes the spiritual, emotive and philosophical in drawing attention to the ethical irresponsibility and socio-spiritual repercussions of ignoring social disadvantage in education. It includes inherences and impressions of humaneness in education. It seeks both introspection and insight into what ‘the human condition’ might mean to a just and robust education of children. In this sense, it is a personal inquiry as reflexive narrative journeying (ibid) based on twenty seven years of teaching in a primary school in a vulnerable and economically-impoverished community in the province of KwaZulu Natal in South Africa. As a writing-as-inquiry journeying, I engage with ‘critical rhizomatic narrative’ methodology (Swanson, 2004) as it resonates with the explorations of lived experiences that pertain to emotions, feelings, values and spirituality and because it enables a process of seeking what it might mean to be(come) human(e). This study is a philosophical rhizomatic narrative rendering which is an approach to(wards) understandings of personal growth and spirituality through understanding the various emergent journeys of life and the meanings that we can elicit from them to become more human and thus more humane.
- Full Text:
- Date Issued: 2013
Optimisation of a mini horizontal axis wind turbine to increase energy yield during short duration wind variations
- Authors: Poole, Sean Nichola
- Date: 2017
- Subjects: Wind turbines -- Design and construction , Horizontal axis wind turbines -- Blades , Wind turbines -- Aerodynamics , Wind power
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/7036 , vital:21196
- Description: The typical methodology for analytically designing a wind turbine blade is by means of blade element momentum (BEM) theory, whereby the aerofoil angle of attack is optimized to achieve a maximum lift-to-drag ratio. This research aims to show that an alternative optimisation methodology could yield better results, especially in gusty and turbulent wind conditions. This alternative method looks at increasing the aerofoil Reynolds number by increasing the aerofoil chord length. The increased Reynolds number generally increases the e_ectiveness of the aerofoil which would result in a higher or similar lift-to-drag ratio (even at the decreased angle of attacked require to maintain the turbine thrust coe_cient). The bene_t of this design is a atter power curve which causes the turbine to be less sensitive to uctuating winds. Also, the turbine has more torque at startup, allowing for operatation in lower wind speeds. This research is assumed to only be applicable to small wind turbines which operated in a low Reynolds number regime (<500 000), where Reynolds number manipulation is most advantageous.
- Full Text:
- Date Issued: 2017
- Authors: Poole, Sean Nichola
- Date: 2017
- Subjects: Wind turbines -- Design and construction , Horizontal axis wind turbines -- Blades , Wind turbines -- Aerodynamics , Wind power
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/7036 , vital:21196
- Description: The typical methodology for analytically designing a wind turbine blade is by means of blade element momentum (BEM) theory, whereby the aerofoil angle of attack is optimized to achieve a maximum lift-to-drag ratio. This research aims to show that an alternative optimisation methodology could yield better results, especially in gusty and turbulent wind conditions. This alternative method looks at increasing the aerofoil Reynolds number by increasing the aerofoil chord length. The increased Reynolds number generally increases the e_ectiveness of the aerofoil which would result in a higher or similar lift-to-drag ratio (even at the decreased angle of attacked require to maintain the turbine thrust coe_cient). The bene_t of this design is a atter power curve which causes the turbine to be less sensitive to uctuating winds. Also, the turbine has more torque at startup, allowing for operatation in lower wind speeds. This research is assumed to only be applicable to small wind turbines which operated in a low Reynolds number regime (<500 000), where Reynolds number manipulation is most advantageous.
- Full Text:
- Date Issued: 2017
Knowledge, attitudes, and practices of the treatment options for dental caries among the adult patients for dental caries in Buffalo City Metropolitan Municipality, in East London, Eastern Cape, South Africa
- Authors: Veleekizhakethil, Legy
- Date: 2021-11
- Subjects: Dental caries , Periodontics
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/22968 , vital:53257
- Description: Dentistry offers several caries-preventive measures, some of which emphasise not only patient’s responsibility to manage their disease, but also how dental professionals should manage it. Consequently, this study aimed to examine the knowledge, attitudes, and practices of adult patients towards treatment options relating to dental caries in the geographical context of Buffalo City Metropolitan Municipality, situated in the Eastern Cape Province of South Africa. Purpose Firstly, this quantitative study set out to assess the existing oral health knowledge, attitudes, and practices among an adult population visiting dental health facilities in Buffalo City Metropolitan Municipality, in East London, Eastern Cape, South Africa. Secondly, it aimed to examine the prevalence of dental caries, periodontal diseases and tooth associated diseases in this specific setting. Furthermore, the study sought to provide baseline data in order to organise a successful dental prevention programme. The data obtained will determine the layout of policies to be put forward to the Department of Health. Methodology The researcher took a quantitative approach and conducted descriptive surveys from November 2019 to March 2020. A close-ended, structured questionnaire for data collection was designed based on the aspects of knowledge, attitudes, practices and behaviour pertaining to the area of dental caries. A clinical examination of dental status was performed using dental probes, dental mirrors and tooth air-drying. All decay, and missing, filled or restored teeth due to dental caries, along with the presence of calculus, gingival, and periodontal lesions were recorded. Results Participants had an average knowledge score of 80percent with a 95percent confidence interval of (76percent; 84percent). The majority knew the importance of cleaning their teeth (88.9percent), were aware of the effects of sugary diets (80.7percent), avoided sugary foods (64.6percent), and lastly were aware of the causes of dental caries (71.3percent). However it is concerning that most had never visited a dentist, as reflected by 69.1percent of participants agreeing or strongly agreeing. At least 70percent of those who responded were satisfied with their dentists in that they ( the dentists) freely share ideas and opinions and provide advice on options for dental care. The study revealed a high prevalence of dental caries with a ratio of 6.23. Conclusions The majority of the participants affirmed the importance of visiting the dentist for a routine dental examination. In addition, the majority are aware that sugary diets are associated with dental caries. However, there is a high prevalence of dental caries among participants in this setting. Therefore, dentists should provide preventive measures, along with professional restorative and plaque removal, to curb the burden of dental caries and periodontal diseases. The type and extent of preventive measures must be adjusted according to the patient’s individual needs. Dental health professionals must collaborate with other health-care providers to promote preventive dental health. , Thesis (MPH) -- Faculty of Health Sciences, 2021
- Full Text:
- Date Issued: 2021-11
- Authors: Veleekizhakethil, Legy
- Date: 2021-11
- Subjects: Dental caries , Periodontics
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/22968 , vital:53257
- Description: Dentistry offers several caries-preventive measures, some of which emphasise not only patient’s responsibility to manage their disease, but also how dental professionals should manage it. Consequently, this study aimed to examine the knowledge, attitudes, and practices of adult patients towards treatment options relating to dental caries in the geographical context of Buffalo City Metropolitan Municipality, situated in the Eastern Cape Province of South Africa. Purpose Firstly, this quantitative study set out to assess the existing oral health knowledge, attitudes, and practices among an adult population visiting dental health facilities in Buffalo City Metropolitan Municipality, in East London, Eastern Cape, South Africa. Secondly, it aimed to examine the prevalence of dental caries, periodontal diseases and tooth associated diseases in this specific setting. Furthermore, the study sought to provide baseline data in order to organise a successful dental prevention programme. The data obtained will determine the layout of policies to be put forward to the Department of Health. Methodology The researcher took a quantitative approach and conducted descriptive surveys from November 2019 to March 2020. A close-ended, structured questionnaire for data collection was designed based on the aspects of knowledge, attitudes, practices and behaviour pertaining to the area of dental caries. A clinical examination of dental status was performed using dental probes, dental mirrors and tooth air-drying. All decay, and missing, filled or restored teeth due to dental caries, along with the presence of calculus, gingival, and periodontal lesions were recorded. Results Participants had an average knowledge score of 80percent with a 95percent confidence interval of (76percent; 84percent). The majority knew the importance of cleaning their teeth (88.9percent), were aware of the effects of sugary diets (80.7percent), avoided sugary foods (64.6percent), and lastly were aware of the causes of dental caries (71.3percent). However it is concerning that most had never visited a dentist, as reflected by 69.1percent of participants agreeing or strongly agreeing. At least 70percent of those who responded were satisfied with their dentists in that they ( the dentists) freely share ideas and opinions and provide advice on options for dental care. The study revealed a high prevalence of dental caries with a ratio of 6.23. Conclusions The majority of the participants affirmed the importance of visiting the dentist for a routine dental examination. In addition, the majority are aware that sugary diets are associated with dental caries. However, there is a high prevalence of dental caries among participants in this setting. Therefore, dentists should provide preventive measures, along with professional restorative and plaque removal, to curb the burden of dental caries and periodontal diseases. The type and extent of preventive measures must be adjusted according to the patient’s individual needs. Dental health professionals must collaborate with other health-care providers to promote preventive dental health. , Thesis (MPH) -- Faculty of Health Sciences, 2021
- Full Text:
- Date Issued: 2021-11
Isolating the consumer determinants of choice when making a purchasing decision in a supplier company
- Authors: Williams, Rita Christine
- Date: 2018
- Subjects: Customer relations , Customer services -- Management Consumer satisfaction -- Evaluation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/36048 , vital:33885
- Description: The objective of this research was to establish the determinants of purchase choice by customers and to establish the modality of their decision-making process. The study was conducted at PerkinElmer a scientific equipment supplier company. PerkinElmer South Africa supplies equipment to industrial laboratories, academic laboratories and laboratories in government institutions. It has become clear to the researcher that understanding the customer and what their perceptions are is the key to business success. These insights would give the researcher the knowledge of important factors in the customer modality of purchase decisions. The literature review revealed that there are numerous factors that influences a customer buying decision namely: Customer relationships management, Unique selling proposition, the importance of salespeople, customer satisfaction levels, the brand name, Brand awareness, brand perception, brand loyalty, price, the service levels that the company provides after sale. The customer decision-making process and the various stages involved, an empirical study was conducted utilising in-depth interviews. The five main themes that were investigated through in-depth interviews were the following: Customer relationship management, brand, customer satisfaction levels, price, service. The factors were probed, analysed and compared and each customer’s preference was noted. The study employs a qualitative approach as this stance supports the researcher’s interest in the customer views and perceptions. A small sample was utilised from the scientific sector in the Eastern Cape and the Gauteng area. The empirical results indicated the importance of service support and if this is not in place it can mean the loss of future business. The customers in academia had the common view that the price is most important. The university policy forces the lowest priced equipment to be purchased. The respondents unanimously voiced their concerns regarding the expensiveness of PerkinElmer consumables.
- Full Text:
- Date Issued: 2018
- Authors: Williams, Rita Christine
- Date: 2018
- Subjects: Customer relations , Customer services -- Management Consumer satisfaction -- Evaluation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/36048 , vital:33885
- Description: The objective of this research was to establish the determinants of purchase choice by customers and to establish the modality of their decision-making process. The study was conducted at PerkinElmer a scientific equipment supplier company. PerkinElmer South Africa supplies equipment to industrial laboratories, academic laboratories and laboratories in government institutions. It has become clear to the researcher that understanding the customer and what their perceptions are is the key to business success. These insights would give the researcher the knowledge of important factors in the customer modality of purchase decisions. The literature review revealed that there are numerous factors that influences a customer buying decision namely: Customer relationships management, Unique selling proposition, the importance of salespeople, customer satisfaction levels, the brand name, Brand awareness, brand perception, brand loyalty, price, the service levels that the company provides after sale. The customer decision-making process and the various stages involved, an empirical study was conducted utilising in-depth interviews. The five main themes that were investigated through in-depth interviews were the following: Customer relationship management, brand, customer satisfaction levels, price, service. The factors were probed, analysed and compared and each customer’s preference was noted. The study employs a qualitative approach as this stance supports the researcher’s interest in the customer views and perceptions. A small sample was utilised from the scientific sector in the Eastern Cape and the Gauteng area. The empirical results indicated the importance of service support and if this is not in place it can mean the loss of future business. The customers in academia had the common view that the price is most important. The university policy forces the lowest priced equipment to be purchased. The respondents unanimously voiced their concerns regarding the expensiveness of PerkinElmer consumables.
- Full Text:
- Date Issued: 2018
End-user requirements of an assistive technology for profoundly deaf parents with infants
- Authors: Mxhego, Zukile Bright
- Date: 2023-04
- Subjects: End-user computing , Assistive computer technology , Deaf parents
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/60707 , vital:66373
- Description: As the number of deaf people in the world increases, the amount of parents who are deaf, is also growing. The world is increasingly relying on technology from which deaf parents can, and do, benefit significantly. Deaf parents are able to rely on available technology such as assistive technologies to overcome functional limitations. However, assistive technologies are often abandoned within a short period of time of being acquired. The abandonment of assistive technologies is believed to be due to a lack of proper elicitation of requirements. Therefore, the problem identified in this research is a lack of understanding of end-user requirements of an assistive technology for profoundly deaf parents with infants. A literature review together with logical argumentation was conducted and applied to identify and recommend a method suitable for eliciting end-user requirements for assistive technologies. Thereafter, an integrative literature review and thematic analysis was done to extract needs and challenges of profoundly deaf parents with infants, and group them according to themes that emerged. Finally, making use of the recommended method and the extracted needs and challenges of profoundly deaf parents with infants, twenty-eight end-user requirements of an assistive technology for profoundly deaf parents with infants were elicited. The twenty-eight elicited end-user requirements consist of eighteen end-user requirements that express functions of an assistive technology for profoundly deaf parents with infants, and ten end-user requirements that express an overall goal/objective to be attained by profoundly deaf parents with infants when the assistive technology is designed and developed. To evaluate the elicited end-user requirements, only the eighteen end-user requirements that express functions of an assistive technology for profoundly deaf parents with infants were considered. The evaluation was done by assessing both existing and emerging assistive technologies to understand the comprehensiveness of the eighteen elicited end-user requirements that express functions of an assistive technology for profoundly deaf parents with infants. , Thesis (MIT) -- Faculty of Engineering, the Built Environment and Technology, School of Information and Communication Technology, 2023
- Full Text:
- Date Issued: 2023-04
- Authors: Mxhego, Zukile Bright
- Date: 2023-04
- Subjects: End-user computing , Assistive computer technology , Deaf parents
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/60707 , vital:66373
- Description: As the number of deaf people in the world increases, the amount of parents who are deaf, is also growing. The world is increasingly relying on technology from which deaf parents can, and do, benefit significantly. Deaf parents are able to rely on available technology such as assistive technologies to overcome functional limitations. However, assistive technologies are often abandoned within a short period of time of being acquired. The abandonment of assistive technologies is believed to be due to a lack of proper elicitation of requirements. Therefore, the problem identified in this research is a lack of understanding of end-user requirements of an assistive technology for profoundly deaf parents with infants. A literature review together with logical argumentation was conducted and applied to identify and recommend a method suitable for eliciting end-user requirements for assistive technologies. Thereafter, an integrative literature review and thematic analysis was done to extract needs and challenges of profoundly deaf parents with infants, and group them according to themes that emerged. Finally, making use of the recommended method and the extracted needs and challenges of profoundly deaf parents with infants, twenty-eight end-user requirements of an assistive technology for profoundly deaf parents with infants were elicited. The twenty-eight elicited end-user requirements consist of eighteen end-user requirements that express functions of an assistive technology for profoundly deaf parents with infants, and ten end-user requirements that express an overall goal/objective to be attained by profoundly deaf parents with infants when the assistive technology is designed and developed. To evaluate the elicited end-user requirements, only the eighteen end-user requirements that express functions of an assistive technology for profoundly deaf parents with infants were considered. The evaluation was done by assessing both existing and emerging assistive technologies to understand the comprehensiveness of the eighteen elicited end-user requirements that express functions of an assistive technology for profoundly deaf parents with infants. , Thesis (MIT) -- Faculty of Engineering, the Built Environment and Technology, School of Information and Communication Technology, 2023
- Full Text:
- Date Issued: 2023-04