Pecha Kucha 3: Memories, photographs, and archives: On historicising ‘puberty’ in the present
- Authors: Pinto, Pedro
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143937 , vital:38296 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: In 1997, Valerie Walkerdine incited researchers to use memory and fantasy as devices to explore the gendered meanings of being a child and becoming adult. Since we all once were children, we are in the ambiguous – and therefore productive – position of being both informants and ethnographers of childhood experiences. Whilst drawing on a historical investigation on puberty science, this presentation is a hybrid experiment: it combines my memories of growing up in Portugal in the early 1980s and photographs of children taken in clinical interventions from the late nineteenth century to the first decades of the twentieth. In articulating these materials and their different temporalities, my purpose is to explore the techniques and the power relations in which pubertal development came to being thought of, and disciplined, in contemporary societies. In doing so, I invite the possibility of historicising experience as a strategy to critically analyse our medicalised present.
- Full Text:
- Authors: Pinto, Pedro
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143937 , vital:38296 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: In 1997, Valerie Walkerdine incited researchers to use memory and fantasy as devices to explore the gendered meanings of being a child and becoming adult. Since we all once were children, we are in the ambiguous – and therefore productive – position of being both informants and ethnographers of childhood experiences. Whilst drawing on a historical investigation on puberty science, this presentation is a hybrid experiment: it combines my memories of growing up in Portugal in the early 1980s and photographs of children taken in clinical interventions from the late nineteenth century to the first decades of the twentieth. In articulating these materials and their different temporalities, my purpose is to explore the techniques and the power relations in which pubertal development came to being thought of, and disciplined, in contemporary societies. In doing so, I invite the possibility of historicising experience as a strategy to critically analyse our medicalised present.
- Full Text:
Pedagogical translanguaging bridging discourses in South African science classrooms
- Authors: Probyn, Margie J
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/483750 , vital:78795 , https://doi.org/10.1080/09500782.2014.994525
- Description: This paper reports on the classroom languaging practices of a group of science teachers in rural and township schools in South Africa where the majority of learners learn through the medium of English, despite the fact that it is the home language of only a small minority; and learners’ poor English proficiency frequently restricts their access to the curriculum. The purpose of the study was to explore how these science teachers utilised the linguistic resources of the classroom – the learners’ home language and English – and if their practices might improve learners’ opportunity to learn science. A series of lessons for each teacher was videotaped and the teachers were interviewed on their language attitudes and practices.
- Full Text:
- Authors: Probyn, Margie J
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/483750 , vital:78795 , https://doi.org/10.1080/09500782.2014.994525
- Description: This paper reports on the classroom languaging practices of a group of science teachers in rural and township schools in South Africa where the majority of learners learn through the medium of English, despite the fact that it is the home language of only a small minority; and learners’ poor English proficiency frequently restricts their access to the curriculum. The purpose of the study was to explore how these science teachers utilised the linguistic resources of the classroom – the learners’ home language and English – and if their practices might improve learners’ opportunity to learn science. A series of lessons for each teacher was videotaped and the teachers were interviewed on their language attitudes and practices.
- Full Text:
Perceived breach and violation of the psychological contract in a collectivistic culture
- Van der Merwe, Sophie Wilhelmine
- Authors: Van der Merwe, Sophie Wilhelmine
- Date: 2015
- Subjects: Collectivism , Employees -- Attitudes , Contracts -- Psychological aspects , Industrial relations , Breach of contract , Personnel management -- Psychological aspects , Organizational behavior , Psychology, Industrial
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:855 , http://hdl.handle.net/10962/d1017523
- Description: The significance of relationships on economic actions and employee behaviour makes it critical for employers to understand the dynamics of employment through mutual obligations (Rousseau, 1990; Guest, 2004b). The psychological contract affords a broad platform to study the employment relationship (Thomas et al., 2010), and is an important tool for organisational success (McDermott et al., 2013). The literature review contained in this study indicates the differences in contracting environments due to the prevailing cultural orientation. However, there is a dearth of research in collectivistic culture, to which this study will add. The literature also makes a distinction between perceptions of breach and violation. While perceptions of breach of the psychological contract is the perception that the employer has not met all obligations and promises, violation is the emotional and affective state following breach (Morrison & Robinson, 1997) and results in negative or deviant behaviours (Chiu & Peng, 2008). Both breach and violation perceptions negatively affect employee behaviours and attitudes in the workplace (Aggarwal & Bhargava, 2014). This research assumed a constructivist paradigm and builds understanding of the outcomes of breach and violation of the psychological contract on employees’ working life in a collectivistic environment. Primary data collection was by in-depth semi-structured, one on one interviews with five employees of a state-subsidised organisation in East London, making use of convenience sampling. Follow up interviews were conducted, resulting in 7ₑ/₄ hours of interviewing time. Cultural orientation was ascertained through the use of a questionnaire. The findings of this study confirmed that the type of psychological contract entered into influences the outcomes of perceptions of breach and violation. Both dimensions of collectivism, namely institutional and in-group, were practised in this environment, which also impacted on both the individual’s experience and outcomes for the organisation. The latter was influenced by commitment to organisational goals and supervisory or collegial relationships. Most notable of the results is the effect of expectations of transitional justice on experience of the psychological contract. Practical implications and recommendations for future research are made. This research is presented in three sections; firstly the research is presented in the format of an academic paper and includes a concise summary of literature and research method. The second section is an expanded literature review of the psychological contract and its influencing factors, as well as the outcomes of breach and violation. The last section describes and justifies in detail the design of the research and the research procedure followed. , Alternate name: Van der Merwe, Somine
- Full Text:
- Authors: Van der Merwe, Sophie Wilhelmine
- Date: 2015
- Subjects: Collectivism , Employees -- Attitudes , Contracts -- Psychological aspects , Industrial relations , Breach of contract , Personnel management -- Psychological aspects , Organizational behavior , Psychology, Industrial
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:855 , http://hdl.handle.net/10962/d1017523
- Description: The significance of relationships on economic actions and employee behaviour makes it critical for employers to understand the dynamics of employment through mutual obligations (Rousseau, 1990; Guest, 2004b). The psychological contract affords a broad platform to study the employment relationship (Thomas et al., 2010), and is an important tool for organisational success (McDermott et al., 2013). The literature review contained in this study indicates the differences in contracting environments due to the prevailing cultural orientation. However, there is a dearth of research in collectivistic culture, to which this study will add. The literature also makes a distinction between perceptions of breach and violation. While perceptions of breach of the psychological contract is the perception that the employer has not met all obligations and promises, violation is the emotional and affective state following breach (Morrison & Robinson, 1997) and results in negative or deviant behaviours (Chiu & Peng, 2008). Both breach and violation perceptions negatively affect employee behaviours and attitudes in the workplace (Aggarwal & Bhargava, 2014). This research assumed a constructivist paradigm and builds understanding of the outcomes of breach and violation of the psychological contract on employees’ working life in a collectivistic environment. Primary data collection was by in-depth semi-structured, one on one interviews with five employees of a state-subsidised organisation in East London, making use of convenience sampling. Follow up interviews were conducted, resulting in 7ₑ/₄ hours of interviewing time. Cultural orientation was ascertained through the use of a questionnaire. The findings of this study confirmed that the type of psychological contract entered into influences the outcomes of perceptions of breach and violation. Both dimensions of collectivism, namely institutional and in-group, were practised in this environment, which also impacted on both the individual’s experience and outcomes for the organisation. The latter was influenced by commitment to organisational goals and supervisory or collegial relationships. Most notable of the results is the effect of expectations of transitional justice on experience of the psychological contract. Practical implications and recommendations for future research are made. This research is presented in three sections; firstly the research is presented in the format of an academic paper and includes a concise summary of literature and research method. The second section is an expanded literature review of the psychological contract and its influencing factors, as well as the outcomes of breach and violation. The last section describes and justifies in detail the design of the research and the research procedure followed. , Alternate name: Van der Merwe, Somine
- Full Text:
Perceived undersupply of local labour in the presence of unemployment: a case of selected Sundays River Valley citrus farms, 2013
- Authors: Chirara, Malon Tinotenda
- Date: 2015
- Subjects: Unemployment -- South Africa -- Sundays River (Eastern Cape) , Citrus fruit industry -- South Africa -- Sundays River (Eastern Cape) , Labor market -- South Africa -- Sundays River (Eastern Cape) , Work environment -- South Africa -- Sundays River (Eastern Cape) , Agricultural wages -- South Africa -- Sundays River (Eastern Cape) , Agricultural laborers -- South Africa -- Sundays River (Eastern Cape) , Seasonal labor -- South Africa -- Sundays River (Eastern Cape) , Migrant agricultural laborers -- South Africa -- Sundays River (Eastern Cape) , Personnel management -- South Africa -- Sundays River (Eastern Cape)
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1125 , http://hdl.handle.net/10962/d1020367
- Description: While skilled labour shortages are common in many countries, including South Africa, mainly due to a skills mismatch, the undersupply of unskilled labour was less expected, especially in developing countries with high unemployment. The thesis utilises data on perceived worker undersupply on selected citrus farms in the Sundays River Valley (SRV), located in the Eastern Cape Province of South Africa, collected in 2013, to analyse why unemployed residents, surprisingly, do not fill up vacancies on farms. In contrast to other labour markets, farm employment is not restricted by educational levels and as workers reported, with little training the various job tasks and skills required are easy and quick to grasp. At a time the government is trying to find ways of reducing unemployment, and the SRV Municipality (2012:29) reported approximately 42% unemployment, the question arises as to why the relatively low educated residents do not take advantage of the employment opportunities on farms. According to local workers and unemployed residents, the farm job was unattractive largely because of a combination of two factors: perceived relatively low salaries partly caused by the availability of migrant seasonal workers accepting lower remuneration and poor non-wage working conditions. The survey also found that farmers preferred migrant workers because they were more productive compared to their local counterparts who were, reportedly, characterised by high absenteeism and laziness, caused mainly by a reliance on social grants and alcohol abuse. Other reasons given for the unattractiveness of the farm job included the seasonal nature of farm employment, which left workers with no source of income in the offseason, the redundancy associated with farm tasks, perceived poor treatment of workers and lack of information on UIF and Provident funds to farm workers. To address problems associated with the dislike of farm work, seasonality of on-farm employment and the reportedly relatively low income, farm managers, the local municipality and the Labour Department could possibly be involved in creating more communal agricultural projects and help provide local community members to venture into supporting alternative careers within the Hospitality, Ecotourism and Conservation Industries through training programmes. Farm managers may need to consider improving their working relationship with workers in communication and when assigning tasks. Farmers and the local municipality could also consider investing in training programmes for the unemployed residents to equip them with technical skills that can improve their chances of finding jobs.
- Full Text:
- Authors: Chirara, Malon Tinotenda
- Date: 2015
- Subjects: Unemployment -- South Africa -- Sundays River (Eastern Cape) , Citrus fruit industry -- South Africa -- Sundays River (Eastern Cape) , Labor market -- South Africa -- Sundays River (Eastern Cape) , Work environment -- South Africa -- Sundays River (Eastern Cape) , Agricultural wages -- South Africa -- Sundays River (Eastern Cape) , Agricultural laborers -- South Africa -- Sundays River (Eastern Cape) , Seasonal labor -- South Africa -- Sundays River (Eastern Cape) , Migrant agricultural laborers -- South Africa -- Sundays River (Eastern Cape) , Personnel management -- South Africa -- Sundays River (Eastern Cape)
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1125 , http://hdl.handle.net/10962/d1020367
- Description: While skilled labour shortages are common in many countries, including South Africa, mainly due to a skills mismatch, the undersupply of unskilled labour was less expected, especially in developing countries with high unemployment. The thesis utilises data on perceived worker undersupply on selected citrus farms in the Sundays River Valley (SRV), located in the Eastern Cape Province of South Africa, collected in 2013, to analyse why unemployed residents, surprisingly, do not fill up vacancies on farms. In contrast to other labour markets, farm employment is not restricted by educational levels and as workers reported, with little training the various job tasks and skills required are easy and quick to grasp. At a time the government is trying to find ways of reducing unemployment, and the SRV Municipality (2012:29) reported approximately 42% unemployment, the question arises as to why the relatively low educated residents do not take advantage of the employment opportunities on farms. According to local workers and unemployed residents, the farm job was unattractive largely because of a combination of two factors: perceived relatively low salaries partly caused by the availability of migrant seasonal workers accepting lower remuneration and poor non-wage working conditions. The survey also found that farmers preferred migrant workers because they were more productive compared to their local counterparts who were, reportedly, characterised by high absenteeism and laziness, caused mainly by a reliance on social grants and alcohol abuse. Other reasons given for the unattractiveness of the farm job included the seasonal nature of farm employment, which left workers with no source of income in the offseason, the redundancy associated with farm tasks, perceived poor treatment of workers and lack of information on UIF and Provident funds to farm workers. To address problems associated with the dislike of farm work, seasonality of on-farm employment and the reportedly relatively low income, farm managers, the local municipality and the Labour Department could possibly be involved in creating more communal agricultural projects and help provide local community members to venture into supporting alternative careers within the Hospitality, Ecotourism and Conservation Industries through training programmes. Farm managers may need to consider improving their working relationship with workers in communication and when assigning tasks. Farmers and the local municipality could also consider investing in training programmes for the unemployed residents to equip them with technical skills that can improve their chances of finding jobs.
- Full Text:
Perceptions of being a learner: an investigation into how first year Journalism students at a South African university construct themselves as learners
- Authors: Lunga, Carolyne Mande
- Date: 2015
- Subjects: Journalism -- Study and teaching (Higher) -- South Africa , Students -- Attitudes , Students -- Self-rating of -- South Africa , Discourse analysis, Narrative , Active learning -- South Africa , Learning -- Evaluation , Learning, Psychology of , College freshmen -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1332 , http://hdl.handle.net/10962/d1020026
- Description: The aim of the research reported in this document was to explore the ways in which first year Journalism students at a South African University construct themselves as learners. The research adopted a case study approach of purposively selected first year journalism students. In exploring this area, focus group and individual in-depth interviewing were employed which illuminated important aspects of learner identity construction. In order to make sense of these self-constructions, the research was located in the larger debates on discourse as espoused by Michel Foucault who argues that discourse constructs subjectivities. The research demonstrated that there were various discourses at play which influenced how these learners spoke and behaved. The influence of these discourses on learners' experiences varied at different times of the year. For example, the awarding of the Duly Performed (DP) certificate for students who met the minimum attendance and work requirements of a particular course, the giving of tests, exercises and examinations were some of the technologies that 'forced' students into compliance. In terms of identity formation, the heterogeneous nature of 'being' a journalism 'student' revealed that the different discourses at play influenced learner behaviour and that their identities continued to change over the year. Doing additional subjects such as Sociology, Drama, Art History and others at the same time as Journalism and Media Studies also meant that the learners had to negotiate the differing role requirements.
- Full Text:
- Authors: Lunga, Carolyne Mande
- Date: 2015
- Subjects: Journalism -- Study and teaching (Higher) -- South Africa , Students -- Attitudes , Students -- Self-rating of -- South Africa , Discourse analysis, Narrative , Active learning -- South Africa , Learning -- Evaluation , Learning, Psychology of , College freshmen -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1332 , http://hdl.handle.net/10962/d1020026
- Description: The aim of the research reported in this document was to explore the ways in which first year Journalism students at a South African University construct themselves as learners. The research adopted a case study approach of purposively selected first year journalism students. In exploring this area, focus group and individual in-depth interviewing were employed which illuminated important aspects of learner identity construction. In order to make sense of these self-constructions, the research was located in the larger debates on discourse as espoused by Michel Foucault who argues that discourse constructs subjectivities. The research demonstrated that there were various discourses at play which influenced how these learners spoke and behaved. The influence of these discourses on learners' experiences varied at different times of the year. For example, the awarding of the Duly Performed (DP) certificate for students who met the minimum attendance and work requirements of a particular course, the giving of tests, exercises and examinations were some of the technologies that 'forced' students into compliance. In terms of identity formation, the heterogeneous nature of 'being' a journalism 'student' revealed that the different discourses at play influenced learner behaviour and that their identities continued to change over the year. Doing additional subjects such as Sociology, Drama, Art History and others at the same time as Journalism and Media Studies also meant that the learners had to negotiate the differing role requirements.
- Full Text:
Perceptions of the natural environment from a rural African perspective: a case of Cylondropuntia fulgida var. fulgida in Gwanda district, Zimbabwe
- Dube, Nqobizitha, Snowball, Jeanette D, Fraser, Gavin C G
- Authors: Dube, Nqobizitha , Snowball, Jeanette D , Fraser, Gavin C G
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68578 , vital:29289 , http://2015.essa.org.za/fullpaper/essa_2994.pdf
- Description: Publisher version , Community environmental perceptions are instrumental in environmental management programmes given that perspectives govern human-environment relations. Despite numerous studies on environmental perceptions, little is known about how the rural poor particularly in Africa conceptualize, live with, and respond to pressing environmental issues facing them. As such, this paper uses the case of an invasive alien plant (IAP) (Cylindropuntia fulgida var. fulgida (Cff)) in a rural community (Gwanda district, Zimbabwe) to unveil the conceptualisation of the natural environment from a rural African perspective. This paper discloses the environmental worldview of the community and explains the formulation of the attitudes by the local households towards species in the environment. The study uses two horizontal dimensions of environmental attitudes formulation (New Environmental Paradigm (NEP) Scale and Kellet’s (1996) classification of environmental values). Data was collected using a questionnaire survey, group discussions and key informant interviews. A sample of 156 individuals comprised the study respondents. Results showed the residents of rural Gwanda district to hold both a conservation and utilisation conviction (syncretic view) towards the environment. However, utilisation outweighs conservation. Furthermore, older residents are more inclined to conservation in comparison to the youth. The study also divulged that the origin of a species in the natural environment was insignificant to the host community. However, the livelihood effects that species had (regardless of origins) were the major determinants of attitudes developed towards it.
- Full Text:
- Authors: Dube, Nqobizitha , Snowball, Jeanette D , Fraser, Gavin C G
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68578 , vital:29289 , http://2015.essa.org.za/fullpaper/essa_2994.pdf
- Description: Publisher version , Community environmental perceptions are instrumental in environmental management programmes given that perspectives govern human-environment relations. Despite numerous studies on environmental perceptions, little is known about how the rural poor particularly in Africa conceptualize, live with, and respond to pressing environmental issues facing them. As such, this paper uses the case of an invasive alien plant (IAP) (Cylindropuntia fulgida var. fulgida (Cff)) in a rural community (Gwanda district, Zimbabwe) to unveil the conceptualisation of the natural environment from a rural African perspective. This paper discloses the environmental worldview of the community and explains the formulation of the attitudes by the local households towards species in the environment. The study uses two horizontal dimensions of environmental attitudes formulation (New Environmental Paradigm (NEP) Scale and Kellet’s (1996) classification of environmental values). Data was collected using a questionnaire survey, group discussions and key informant interviews. A sample of 156 individuals comprised the study respondents. Results showed the residents of rural Gwanda district to hold both a conservation and utilisation conviction (syncretic view) towards the environment. However, utilisation outweighs conservation. Furthermore, older residents are more inclined to conservation in comparison to the youth. The study also divulged that the origin of a species in the natural environment was insignificant to the host community. However, the livelihood effects that species had (regardless of origins) were the major determinants of attitudes developed towards it.
- Full Text:
Performance management of health professionals : an evaluation research study of health services in the subdistrict of Buffalo City in the Provincial Department of Health in the Eastern Cape
- Authors: Booi, Mlungisi Wellington
- Date: 2015
- Subjects: South Africa -- Department of Health , Batho Pele (Program) , Public health personnel -- South Africa -- Buffalo City , Employees -- Rating of -- South Africa -- Buffalo City , Public health -- South Africa -- Buffalo City -- Evaluation , Customer services -- South Africa -- Buffalo City -- Evaluation , Employees -- Training of -- South Africa -- Buffalo City , Employee-management relations in government -- South Africa -- Buffalo City
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:859 , http://hdl.handle.net/10962/d1020017
- Description: Integrative Summary In 1997 the Minister of Public Service and Administration of South Africa, Zola Skweyiya, introduced the White Paper on Transforming Public Service Delivery(Department of Public Service and Administration(DPSA,1997: 1). It was premised on what was called Batho Pele (DPSA, 1997: 9), giving effect to Section 197 of the Constitution, Act 108 of 1996 as amended. A linkage to performance management can be found from the assertion made in the White Paper that in future the Batho Pele would form the basis of any assessment of the performance of individual staff and that would contribute to improving the delivery of service (DPSA, 1997:16). Another factor that contributed to the utilisation of a performance management system was the recommendation put forward by the Public Service Commission of South Africa( PSC,2004: 16),that called for public institutions to adopt a clear, comprehensive performance management and evaluation framework for the delivery of public service. That was expected to turn around the ailing public institutions whose record of serving the public with pride and dignity was on the decline. The research aim was to evaluate the effectiveness of the performance management system in creating and resolving role conflict with health professionals employed by the Buffalo City sub-district. The research goal was divided into three objectives, namely: evaluation of the effectiveness of the performance management system as a managerial tool for health managers to manage their subordinates including both professional and support staff, evaluation of the effectiveness of the performance system from the perspective of the health professional as a subordinate and to analyze the functioning and effectiveness of the system in creating and resolving role conflict between professional conduct and organisational requirements. The respondents noted that the implementation of the system was not matched with appointment at managerial level with officials having relevant managerial capacity. Further to that resources at the coal face of service delivery continued to deteriorate and became very scarce and there is no documented proof that has been found of an effort made to check the compatibility of the system to health professionals. The literature identified negative effects that have emanated from the implementation of the performance management system. The study was conducted by interviewing health professionals from the entry level to the management level within the Buffalo City sub-district from three mini hospitals or Health Care Centres. The respondents indicated that there are positives that have been achieved by the implementation of the system, such as the skills gap identification as well as specific targets contained in annual performance contracts. These targets help motivate health professional to focus on that particular direction of activities. Unfortunately it has been clearly documented that the performance management system has also contributed to the development of role conflict in a number of professionals. It has been documented that the system has not been crafted with a health professional in mind and, as such, appears to favour quantity rather than quality of health services as advocated by the codes of practice of different health professionals. There are a number of recommendations that were put forward by the respondents to try to salvage the system and in mitigation of the identified negative factors. For the improvement of the system, the Eastern Cape Provincial Department of Health has to firstly customise the annual contracts to contain only the fundamental information. Secondly need to improve the transparency pertaining to financial pressures facing the Health Department. Thirdly the provision of essential enablers, need to be prioritised. Fourthly there is a need to upgrade the system to incorporate 360 degree feedback. Further research recommendations include a bigger sample incorporating different research methods and to also incorporate searches for measures that can be implemented to improve the system to be more relevant to health professionals. This document is organised and presented in three sections. The first section is the evaluation report with a review of literature, research methodology, findings, discussion and conclusion. The second section is where an indepth literature review is located and the last section details the research methodology.
- Full Text:
- Authors: Booi, Mlungisi Wellington
- Date: 2015
- Subjects: South Africa -- Department of Health , Batho Pele (Program) , Public health personnel -- South Africa -- Buffalo City , Employees -- Rating of -- South Africa -- Buffalo City , Public health -- South Africa -- Buffalo City -- Evaluation , Customer services -- South Africa -- Buffalo City -- Evaluation , Employees -- Training of -- South Africa -- Buffalo City , Employee-management relations in government -- South Africa -- Buffalo City
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:859 , http://hdl.handle.net/10962/d1020017
- Description: Integrative Summary In 1997 the Minister of Public Service and Administration of South Africa, Zola Skweyiya, introduced the White Paper on Transforming Public Service Delivery(Department of Public Service and Administration(DPSA,1997: 1). It was premised on what was called Batho Pele (DPSA, 1997: 9), giving effect to Section 197 of the Constitution, Act 108 of 1996 as amended. A linkage to performance management can be found from the assertion made in the White Paper that in future the Batho Pele would form the basis of any assessment of the performance of individual staff and that would contribute to improving the delivery of service (DPSA, 1997:16). Another factor that contributed to the utilisation of a performance management system was the recommendation put forward by the Public Service Commission of South Africa( PSC,2004: 16),that called for public institutions to adopt a clear, comprehensive performance management and evaluation framework for the delivery of public service. That was expected to turn around the ailing public institutions whose record of serving the public with pride and dignity was on the decline. The research aim was to evaluate the effectiveness of the performance management system in creating and resolving role conflict with health professionals employed by the Buffalo City sub-district. The research goal was divided into three objectives, namely: evaluation of the effectiveness of the performance management system as a managerial tool for health managers to manage their subordinates including both professional and support staff, evaluation of the effectiveness of the performance system from the perspective of the health professional as a subordinate and to analyze the functioning and effectiveness of the system in creating and resolving role conflict between professional conduct and organisational requirements. The respondents noted that the implementation of the system was not matched with appointment at managerial level with officials having relevant managerial capacity. Further to that resources at the coal face of service delivery continued to deteriorate and became very scarce and there is no documented proof that has been found of an effort made to check the compatibility of the system to health professionals. The literature identified negative effects that have emanated from the implementation of the performance management system. The study was conducted by interviewing health professionals from the entry level to the management level within the Buffalo City sub-district from three mini hospitals or Health Care Centres. The respondents indicated that there are positives that have been achieved by the implementation of the system, such as the skills gap identification as well as specific targets contained in annual performance contracts. These targets help motivate health professional to focus on that particular direction of activities. Unfortunately it has been clearly documented that the performance management system has also contributed to the development of role conflict in a number of professionals. It has been documented that the system has not been crafted with a health professional in mind and, as such, appears to favour quantity rather than quality of health services as advocated by the codes of practice of different health professionals. There are a number of recommendations that were put forward by the respondents to try to salvage the system and in mitigation of the identified negative factors. For the improvement of the system, the Eastern Cape Provincial Department of Health has to firstly customise the annual contracts to contain only the fundamental information. Secondly need to improve the transparency pertaining to financial pressures facing the Health Department. Thirdly the provision of essential enablers, need to be prioritised. Fourthly there is a need to upgrade the system to incorporate 360 degree feedback. Further research recommendations include a bigger sample incorporating different research methods and to also incorporate searches for measures that can be implemented to improve the system to be more relevant to health professionals. This document is organised and presented in three sections. The first section is the evaluation report with a review of literature, research methodology, findings, discussion and conclusion. The second section is where an indepth literature review is located and the last section details the research methodology.
- Full Text:
Performing whiteness; representing otherness : Hugh Tracey and African music
- Authors: Coetzee, Paulette June
- Date: 2015
- Subjects: Tracey, Hugh , Music -- Africa , International Library of African Music , Ethnomusicology -- Africa , Ethnomusicologists -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2327 , http://hdl.handle.net/10962/d1016502
- Description: This thesis provides a critical study of texts associated with Hugh Tracey (1903–1977). Tracey is well-known for his work in African music studies, particularly for his major contribution to the recorded archive of musical sound in sub-Saharan Africa and his founding of the International Library of African Music (ILAM) in 1954. My reading of him is informed by a postcolonial perspective, whiteness studies and African scholarship on ways in which constructions of African identity and tradition have been shaped by the colonial archive. In my view, Tracey was part of a mid-twentieth century movement which sought to marshal positive representations of traditional African culture in the interest of maintaining and strengthening colonial rule. While his recording project may have fostered inclusion through creating spaces for indigenous musicians to be heard, it also functioned to promote racist exclusion in the manner of its production, distribution and claims to expertise. Moreover, his initial strategy for ILAM’s sustainability targeted colonial government and industry as primary clients, with the promise that promoting traditional music as a means of entertainment and self-expression for black subjects and workers would ease administration and reduce conflict. I believe that it is important to acknowledge and interrogate the problematic racial attitudes and practices associated with the history of Tracey’s archive – not to undermine its significance in any way but to allow it to be better understood and used more productively in the future.
- Full Text:
- Authors: Coetzee, Paulette June
- Date: 2015
- Subjects: Tracey, Hugh , Music -- Africa , International Library of African Music , Ethnomusicology -- Africa , Ethnomusicologists -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2327 , http://hdl.handle.net/10962/d1016502
- Description: This thesis provides a critical study of texts associated with Hugh Tracey (1903–1977). Tracey is well-known for his work in African music studies, particularly for his major contribution to the recorded archive of musical sound in sub-Saharan Africa and his founding of the International Library of African Music (ILAM) in 1954. My reading of him is informed by a postcolonial perspective, whiteness studies and African scholarship on ways in which constructions of African identity and tradition have been shaped by the colonial archive. In my view, Tracey was part of a mid-twentieth century movement which sought to marshal positive representations of traditional African culture in the interest of maintaining and strengthening colonial rule. While his recording project may have fostered inclusion through creating spaces for indigenous musicians to be heard, it also functioned to promote racist exclusion in the manner of its production, distribution and claims to expertise. Moreover, his initial strategy for ILAM’s sustainability targeted colonial government and industry as primary clients, with the promise that promoting traditional music as a means of entertainment and self-expression for black subjects and workers would ease administration and reduce conflict. I believe that it is important to acknowledge and interrogate the problematic racial attitudes and practices associated with the history of Tracey’s archive – not to undermine its significance in any way but to allow it to be better understood and used more productively in the future.
- Full Text:
PFB0595w is a Plasmodium falciparum J protein that co-localizes with PfHsp70-1 and can stimulate its in vitro ATP hydrolysis activity
- Njunge, James M, Mandal, Pradipta, Przyborski, Jude M, Boshoff, Aileen, Pesce, Eva-Rachele, Blatch, Gregory L
- Authors: Njunge, James M , Mandal, Pradipta , Przyborski, Jude M , Boshoff, Aileen , Pesce, Eva-Rachele , Blatch, Gregory L
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431739 , vital:72800 , xlink:href="https://doi.org/10.1016/j.biocel.2015.02.008"
- Description: Heat shock proteins, many of which function as molecular chaperones, play important roles in the lifecycle and pathogenesis of the malaria parasite, Plasmodium falciparum. The P. falciparum heat shock protein 70 (PfHsp70) family of chaperones is potentially regulated by a large complement of J proteins that localize to various intracellular compartments including the infected erythrocyte cytosol. While PfHsp70-1 has been shown to be an abundant cytosolic chaperone, its regulation by J proteins is poorly understood. In this study, we characterized the J protein PFB0595w, a homologue of the well-studied yeast cytosolic J protein, Sis1. PFB0595w, similarly to PfHsp70-1, was localized to the parasite cytosol and its expression was upregulated by heat shock. Additionally, recombinant PFB0595w was shown to be dimeric and to stimulate the in vitro ATPase activity of PfHsp70-1. Overall, the expression, localization and biochemical data for PFB0595w suggest that it may function as a cochaperone of PfHsp70-1, and advances current knowledge on the chaperone machinery of the parasite.
- Full Text:
- Authors: Njunge, James M , Mandal, Pradipta , Przyborski, Jude M , Boshoff, Aileen , Pesce, Eva-Rachele , Blatch, Gregory L
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431739 , vital:72800 , xlink:href="https://doi.org/10.1016/j.biocel.2015.02.008"
- Description: Heat shock proteins, many of which function as molecular chaperones, play important roles in the lifecycle and pathogenesis of the malaria parasite, Plasmodium falciparum. The P. falciparum heat shock protein 70 (PfHsp70) family of chaperones is potentially regulated by a large complement of J proteins that localize to various intracellular compartments including the infected erythrocyte cytosol. While PfHsp70-1 has been shown to be an abundant cytosolic chaperone, its regulation by J proteins is poorly understood. In this study, we characterized the J protein PFB0595w, a homologue of the well-studied yeast cytosolic J protein, Sis1. PFB0595w, similarly to PfHsp70-1, was localized to the parasite cytosol and its expression was upregulated by heat shock. Additionally, recombinant PFB0595w was shown to be dimeric and to stimulate the in vitro ATPase activity of PfHsp70-1. Overall, the expression, localization and biochemical data for PFB0595w suggest that it may function as a cochaperone of PfHsp70-1, and advances current knowledge on the chaperone machinery of the parasite.
- Full Text:
Photo-physicochemical studies and photodynamic therapy activity of indium and gallium phthalocyanines
- Tshangana, Charmaine Sesethu
- Authors: Tshangana, Charmaine Sesethu
- Date: 2015
- Subjects: Quantum dots , Nanoparticles , Photochemotherapy , Phthalocyanines
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4548 , http://hdl.handle.net/10962/d1017928
- Description: The potential toxicity of seven different types of quantum dots without shell (L-cysteine-CdTe, TGA-CdTe, MPA-CdTe, TGA-CdSe) and with the shell (GSH-CdSe@ZnS, GSH-CdTe@ZnS,) with different capping agents were evaluated. The growth inhibitory effects of the various quantum dots on human pancreatic BON cancerous cells were determined. The least cytotoxic of the various quantum dots synthesized and the one displaying the lowest growth inhibitory potential and no embryotoxicity was determined to be the GSH-CdSe@ZnS quantum dots. The GSH-CdSe@ZnS quantum dots were then conjugated to gallium, aluminium and indium octacarboxy phthalocyanine and the photophysical behaviour of the conjugates studied for potential use in photodynamic therapy and imaging applications. The sizes, morphology, thermal stability and confirmation of successful conjugation was determined using X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR), respectively. The study was extended by conjugating amino functionalized magnetic nanoparticles (Fe₃O₄) to indium octacarboxy phthalocyanine to study the photophysical behaviour of the conjugate as a potential bi-functional anti-cancer agent (hyperthermia and photodynamic therapy applications). A three-in-one multifunctional nanocomposite comprising of the quantum dots, magnetic nanoparticles and indium octacarboxy phthalocyanine was developed with the aim of developing a multifunctional composite that is able detect, monitor and treat cancer. All conjugates showed improved and enhanced photophysical behaviour. Finally, GSH-CdSe@ZnS conjugated to aluminium octacarboxy phthalocyanine was applied in human pancreatic carcinoid BON cells. The conjugates induced cell death dose-dependently.
- Full Text:
- Authors: Tshangana, Charmaine Sesethu
- Date: 2015
- Subjects: Quantum dots , Nanoparticles , Photochemotherapy , Phthalocyanines
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4548 , http://hdl.handle.net/10962/d1017928
- Description: The potential toxicity of seven different types of quantum dots without shell (L-cysteine-CdTe, TGA-CdTe, MPA-CdTe, TGA-CdSe) and with the shell (GSH-CdSe@ZnS, GSH-CdTe@ZnS,) with different capping agents were evaluated. The growth inhibitory effects of the various quantum dots on human pancreatic BON cancerous cells were determined. The least cytotoxic of the various quantum dots synthesized and the one displaying the lowest growth inhibitory potential and no embryotoxicity was determined to be the GSH-CdSe@ZnS quantum dots. The GSH-CdSe@ZnS quantum dots were then conjugated to gallium, aluminium and indium octacarboxy phthalocyanine and the photophysical behaviour of the conjugates studied for potential use in photodynamic therapy and imaging applications. The sizes, morphology, thermal stability and confirmation of successful conjugation was determined using X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR), respectively. The study was extended by conjugating amino functionalized magnetic nanoparticles (Fe₃O₄) to indium octacarboxy phthalocyanine to study the photophysical behaviour of the conjugate as a potential bi-functional anti-cancer agent (hyperthermia and photodynamic therapy applications). A three-in-one multifunctional nanocomposite comprising of the quantum dots, magnetic nanoparticles and indium octacarboxy phthalocyanine was developed with the aim of developing a multifunctional composite that is able detect, monitor and treat cancer. All conjugates showed improved and enhanced photophysical behaviour. Finally, GSH-CdSe@ZnS conjugated to aluminium octacarboxy phthalocyanine was applied in human pancreatic carcinoid BON cells. The conjugates induced cell death dose-dependently.
- Full Text:
Photocatalytic behaviour of zinc tetraamino phthalocyanine-silver nanoparticles immobilized on chitosan beads
- Khoza, Phindile, Nyokong, Tebello
- Authors: Khoza, Phindile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189468 , vital:44849 , xlink:href="https://doi.org/10.1016/j.molcata.2015.01.017"
- Description: Photocatalytic degradation of Rhodamine 6G using unconjugated zinc tetraamino phthalocyanine (ZnTAPc) or when conjugated to Ag nanoparticles (ZnTAPc–AgNPs) is reported. Upon conjugating ZnTAPc to silver nanoparticles, the singlet oxygen production of the phthalocyanine was slightly increased. ZnTAPc and ZnTAPc–AgNPs were immobilized onto chitosan beads for ease of recovery after photocatalysis. Chitosan beads were characterized by FTIR, XRD and TGA. The photodegradation of Rhodamine 6G was used to evaluate the efficiency of the immobilized photocatalysts. In the presence of AgNPs, the photodegradation of Rhodamine 6G was enhanced. The apparent rates (k) were found to be 8.51 × 10−8 and 1.61 × 10−7 mol L−1 min−1 for chitosan supported ZnTAPc or ZnTAPc–AgNPs, respectively. The observation of good photocatalytic activity of the ZnTAPc when immobilized on chitosan proves the uncompromised efficiency of the photocatalysts even when confined in beads, showing great potential for the functionalized beads as heterogeneous catalysts.
- Full Text:
- Authors: Khoza, Phindile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189468 , vital:44849 , xlink:href="https://doi.org/10.1016/j.molcata.2015.01.017"
- Description: Photocatalytic degradation of Rhodamine 6G using unconjugated zinc tetraamino phthalocyanine (ZnTAPc) or when conjugated to Ag nanoparticles (ZnTAPc–AgNPs) is reported. Upon conjugating ZnTAPc to silver nanoparticles, the singlet oxygen production of the phthalocyanine was slightly increased. ZnTAPc and ZnTAPc–AgNPs were immobilized onto chitosan beads for ease of recovery after photocatalysis. Chitosan beads were characterized by FTIR, XRD and TGA. The photodegradation of Rhodamine 6G was used to evaluate the efficiency of the immobilized photocatalysts. In the presence of AgNPs, the photodegradation of Rhodamine 6G was enhanced. The apparent rates (k) were found to be 8.51 × 10−8 and 1.61 × 10−7 mol L−1 min−1 for chitosan supported ZnTAPc or ZnTAPc–AgNPs, respectively. The observation of good photocatalytic activity of the ZnTAPc when immobilized on chitosan proves the uncompromised efficiency of the photocatalysts even when confined in beads, showing great potential for the functionalized beads as heterogeneous catalysts.
- Full Text:
Photodynamic antimicrobial chemotherapy activities of porphyrin- and phthalocyanine-platinum nanoparticle conjugates
- Authors: Managa, Muthumuni Elizabeth
- Date: 2015
- Subjects: Photochemotherapy , Anti-infective agents , Porphyrins , Phthalocyanines , Platinum , Nanoparticles , Bioconjugates , Electrospinning
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4539 , http://hdl.handle.net/10962/d1017919
- Description: This work reports on the conjugation of differently shaped Pt nanoparticles (PtNPs) with ClGa(III) 5,10,15,20-tetrakis-(4-carboxyphenyl) porphyrin (1) as well as chloro - (5,10,15,20-tetrakis (4- (4- carboxy phenycarbonoimidoyl) phenyl) porphyrinato) gallium(III) (2) The work also reports on platination of dihydroxosilicon octacarboxyphthalocyanine (OH)₂SiOCPc (3) to give dihydroxosilicontris(diaquaplatinum)octacarboxyphthalocyanine (OH)₂SiOCPc(Pt)₃ (4). The resulting conjugates were used for photodynamic antimicrobial chemotherapy against S. aureus, E. coli and C. albicans. The degree of photo-inactivation is dependent on concentration of the conjugates, light dose (fluence) and illumination time. The log reduction obtained for 1 when conjugated to cubic PtNPs was 4.64 log (which indicate 99.99 percent of the bacteria have been killed), which is much higher than 3.94 log unit for 1-hexagonal PtNPs and 3.31 log units for 1-unshaped PtNPs. Complex 2 conjugated to hexagonal PtNPs showed 18 nm red shift in the Soret band when compared to 2 alone. Complex 2 and 2-hexagonal PtNPs as well showed promising photodynamic antimicrobial chemotherapy (PACT) activity against S. aureus, E. coli and C. albicans in solution where the log reduction obtained was 4.92, 3.76, and 3.95 respectively for 2-hexagonal PtNPs. The singlet oxygen quantum yields obtained were higher at 0.56 for 2-hexagonl PtNPs in DMF while that of 2 was 0.52 in the same solvent. This resulted in improved PACT activity for 2-hexagonal PtNPs compared to 2. Complex 4 showed slight blue shifting of the absorption spectrum when compared to complex 3 The antimicrobial activity of 4 were promising as the highest log reduction value was observed when compared to the porphyrin conjugates.
- Full Text:
- Authors: Managa, Muthumuni Elizabeth
- Date: 2015
- Subjects: Photochemotherapy , Anti-infective agents , Porphyrins , Phthalocyanines , Platinum , Nanoparticles , Bioconjugates , Electrospinning
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4539 , http://hdl.handle.net/10962/d1017919
- Description: This work reports on the conjugation of differently shaped Pt nanoparticles (PtNPs) with ClGa(III) 5,10,15,20-tetrakis-(4-carboxyphenyl) porphyrin (1) as well as chloro - (5,10,15,20-tetrakis (4- (4- carboxy phenycarbonoimidoyl) phenyl) porphyrinato) gallium(III) (2) The work also reports on platination of dihydroxosilicon octacarboxyphthalocyanine (OH)₂SiOCPc (3) to give dihydroxosilicontris(diaquaplatinum)octacarboxyphthalocyanine (OH)₂SiOCPc(Pt)₃ (4). The resulting conjugates were used for photodynamic antimicrobial chemotherapy against S. aureus, E. coli and C. albicans. The degree of photo-inactivation is dependent on concentration of the conjugates, light dose (fluence) and illumination time. The log reduction obtained for 1 when conjugated to cubic PtNPs was 4.64 log (which indicate 99.99 percent of the bacteria have been killed), which is much higher than 3.94 log unit for 1-hexagonal PtNPs and 3.31 log units for 1-unshaped PtNPs. Complex 2 conjugated to hexagonal PtNPs showed 18 nm red shift in the Soret band when compared to 2 alone. Complex 2 and 2-hexagonal PtNPs as well showed promising photodynamic antimicrobial chemotherapy (PACT) activity against S. aureus, E. coli and C. albicans in solution where the log reduction obtained was 4.92, 3.76, and 3.95 respectively for 2-hexagonal PtNPs. The singlet oxygen quantum yields obtained were higher at 0.56 for 2-hexagonl PtNPs in DMF while that of 2 was 0.52 in the same solvent. This resulted in improved PACT activity for 2-hexagonal PtNPs compared to 2. Complex 4 showed slight blue shifting of the absorption spectrum when compared to complex 3 The antimicrobial activity of 4 were promising as the highest log reduction value was observed when compared to the porphyrin conjugates.
- Full Text:
Photodynamic antimicrobial chemotherapy activity of (5, 10, 15, 20-tetrakis (4-(4-carboxyphenycarbonoimidoyl) phenyl) porphyrinato) chloro gallium (III)
- Managa, Muthumuni, Amuhaya, Edith K, Nyokong, Tebello
- Authors: Managa, Muthumuni , Amuhaya, Edith K , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189043 , vital:44811 , xlink:href="https://doi.org/10.1016/j.saa.2015.06.088"
- Description: (5,10,15,20-Tetrakis(4-(4-carboxyphenycarbonoimidoyl)phenyl)porphyrinato) chloro gallium(III) (complex 1) was conjugated to platinum nanoparticles (PtNPs) (represented as 1-PtNPs). The resulting conjugate showed 18 nm red shift in the Soret band when compared to 1 alone. Complex 1 and 1-PtNPs showed promising photodynamic antimicrobial chemotherapy (PACT) activity against Staphylococcus aureus, Escherichia coli and Candida albicans in solution where the log reductions obtained were 4.92, 3.76, and 3.95, respectively for 1-PtNPs. The singlet oxygen quantum yields obtained were higher at 0.56 for 1-PtNPs in DMF while that of 1 was 0.52 in the same solvent. This resulted in improved PACT activity for 1-PtNPs compared to 1 alone.
- Full Text:
- Authors: Managa, Muthumuni , Amuhaya, Edith K , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189043 , vital:44811 , xlink:href="https://doi.org/10.1016/j.saa.2015.06.088"
- Description: (5,10,15,20-Tetrakis(4-(4-carboxyphenycarbonoimidoyl)phenyl)porphyrinato) chloro gallium(III) (complex 1) was conjugated to platinum nanoparticles (PtNPs) (represented as 1-PtNPs). The resulting conjugate showed 18 nm red shift in the Soret band when compared to 1 alone. Complex 1 and 1-PtNPs showed promising photodynamic antimicrobial chemotherapy (PACT) activity against Staphylococcus aureus, Escherichia coli and Candida albicans in solution where the log reductions obtained were 4.92, 3.76, and 3.95, respectively for 1-PtNPs. The singlet oxygen quantum yields obtained were higher at 0.56 for 1-PtNPs in DMF while that of 1 was 0.52 in the same solvent. This resulted in improved PACT activity for 1-PtNPs compared to 1 alone.
- Full Text:
Photodynamic antimicrobial chemotherapy activity of (5,10,15,20-tetrakis(4-(4-carboxyphenycarbonoimidoyl)phenyl)porphyrinato) chloro gallium(III)
- Managa, Muthumuni, Amuhaya, Edith K, Nyokong, Tebello
- Authors: Managa, Muthumuni , Amuhaya, Edith K , Nyokong, Tebello
- Date: 2015
- Language: English
- Type: Article
- Identifier: vital:7296 , http://hdl.handle.net/10962/d1020359
- Description: (5,10,15,20-Tetrakis(4-(4-carboxyphenycarbonoimidoyl)phenyl)porphyrinato) chloro gallium(III) (complex 1) was conjugated to platinum nanoparticles (PtNPs) (represented as 1-PtNPs). The resulting conjugate showed 18 nm red shift in the Soret band when compared to 1 alone. Complex 1 and 1-PtNPs showed promising photodynamic antimicrobial chemotherapy (PACT) activity against Staphylococcus aureus, Escherichia coli and Candida albicans in solution where the log reductions obtained were 4.92, 3.76, and 3.95, respectively for 1-PtNPs. The singlet oxygen quantum yields obtained were higher at 0.56 for 1-PtNPs in DMF while that of 1 was 0.52 in the same solvent. This resulted in improved PACT activity for 1-PtNPs compared to 1 alone. , Original publication is available at http://dx.doi.org/10.1016/j.saa.2015.06.088
- Full Text: false
- Authors: Managa, Muthumuni , Amuhaya, Edith K , Nyokong, Tebello
- Date: 2015
- Language: English
- Type: Article
- Identifier: vital:7296 , http://hdl.handle.net/10962/d1020359
- Description: (5,10,15,20-Tetrakis(4-(4-carboxyphenycarbonoimidoyl)phenyl)porphyrinato) chloro gallium(III) (complex 1) was conjugated to platinum nanoparticles (PtNPs) (represented as 1-PtNPs). The resulting conjugate showed 18 nm red shift in the Soret band when compared to 1 alone. Complex 1 and 1-PtNPs showed promising photodynamic antimicrobial chemotherapy (PACT) activity against Staphylococcus aureus, Escherichia coli and Candida albicans in solution where the log reductions obtained were 4.92, 3.76, and 3.95, respectively for 1-PtNPs. The singlet oxygen quantum yields obtained were higher at 0.56 for 1-PtNPs in DMF while that of 1 was 0.52 in the same solvent. This resulted in improved PACT activity for 1-PtNPs compared to 1 alone. , Original publication is available at http://dx.doi.org/10.1016/j.saa.2015.06.088
- Full Text: false
Photodynamic antimicrobial chemotherapy activity of gallium tetra-(4-carboxyphenyl) porphyrin when conjugated to differently shaped platinum nanoparticles
- Managa, Muthumuni, Nyokong, Tebello
- Authors: Managa, Muthumuni , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189088 , vital:44815 , xlink:href="https://doi.org/10.1016/j.molstruc.2015.06.077"
- Description: This work reports on the conjugation of differently shaped Pt nanoparticles (PtNPs) with ClGa(III) 5,10,15,20-tetrakis-(4-carboxyphenyl) porphyrin (ClGaTCPP). The resulting conjugates were used for photodynamic antimicrobial chemotherapy against Staphylococcus aureus. The degree of photoinactivation is dependent on concentration of the conjugates, light dose (fluence) and illumination time. The log reduction obtained for ClGaTCPP when conjugated to cubic PtNPs was 4.64 log (which indicate 99.99% of the bacteria have been killed), which is much higher than 3.94 log unit for ClGaTCPPHexagonal PtNPs and 3.31 log units for ClGaTCPP-Unshaped PtNPs. ClGaTCPP alone gave a log unit reduction of less than 3, showing the importance of conjugation to PtNPs.
- Full Text:
- Authors: Managa, Muthumuni , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189088 , vital:44815 , xlink:href="https://doi.org/10.1016/j.molstruc.2015.06.077"
- Description: This work reports on the conjugation of differently shaped Pt nanoparticles (PtNPs) with ClGa(III) 5,10,15,20-tetrakis-(4-carboxyphenyl) porphyrin (ClGaTCPP). The resulting conjugates were used for photodynamic antimicrobial chemotherapy against Staphylococcus aureus. The degree of photoinactivation is dependent on concentration of the conjugates, light dose (fluence) and illumination time. The log reduction obtained for ClGaTCPP when conjugated to cubic PtNPs was 4.64 log (which indicate 99.99% of the bacteria have been killed), which is much higher than 3.94 log unit for ClGaTCPPHexagonal PtNPs and 3.31 log units for ClGaTCPP-Unshaped PtNPs. ClGaTCPP alone gave a log unit reduction of less than 3, showing the importance of conjugation to PtNPs.
- Full Text:
Photodynamic therapy effect of zinc monoamino phthalocyanine–folic acid conjugate adsorbed on single walled carbon nanotubes on melanoma cells
- Ogbodu, Racheal O, Ndhundhuma, Ivy, Karstten, Aletta, Nyokong, Tebello
- Authors: Ogbodu, Racheal O , Ndhundhuma, Ivy , Karstten, Aletta , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241400 , vital:50936 , xlink:href="https://doi.org/10.1016/j.saa.2014.09.033"
- Description: This work reports on the photodynamic therapy effect of zinc monoamino phthalocyanine linked to folic acid represented as ZnMAPc-FA, which was further immobilized onto single walled carbon nanotube represented as ZnMAPc-FA-SWCNT on melanoma A375 cell line, the effect of SWCNT-FA (without ZnMAPc) was also examined. All the compounds were non-toxic to the melanoma A375 cell line in the absence of light. Upon irradiation of the melanoma A375 cell line with a 676 nm diode laser at a power density of 98 mW/cm2 at 5 J/cm2 about 60% and 63% cell death was observed in the presence of ZnMAPc-FA and ZnMAPc-FA-SWCNT respectively. SWCNT-FA had no significant photodynamic therapy or photothermal effect to the cell, only 23% of cell death was observed after irradiation.
- Full Text:
- Authors: Ogbodu, Racheal O , Ndhundhuma, Ivy , Karstten, Aletta , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241400 , vital:50936 , xlink:href="https://doi.org/10.1016/j.saa.2014.09.033"
- Description: This work reports on the photodynamic therapy effect of zinc monoamino phthalocyanine linked to folic acid represented as ZnMAPc-FA, which was further immobilized onto single walled carbon nanotube represented as ZnMAPc-FA-SWCNT on melanoma A375 cell line, the effect of SWCNT-FA (without ZnMAPc) was also examined. All the compounds were non-toxic to the melanoma A375 cell line in the absence of light. Upon irradiation of the melanoma A375 cell line with a 676 nm diode laser at a power density of 98 mW/cm2 at 5 J/cm2 about 60% and 63% cell death was observed in the presence of ZnMAPc-FA and ZnMAPc-FA-SWCNT respectively. SWCNT-FA had no significant photodynamic therapy or photothermal effect to the cell, only 23% of cell death was observed after irradiation.
- Full Text:
Photoinactivation of Candida albicans and Escherichia coli using aluminium phthalocyanine on gold nanoparticles
- Mthethwa, Thandekile, Nyokong, Tebello
- Authors: Mthethwa, Thandekile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189854 , vital:44940 , xlink:href="https://doi.org/10.1039/C4PP00315B"
- Description: The conjugates of aluminium phthalocyanine (complex 1) with gold nanorods (complex 1–AuNRs) and bipyramids (complex 1–AuBPs) showed improved singlet oxygen quantum yields of 0.23 and 0.24, respectively, compared to that of complex 1 alone at 0.12. Complex 1 and its conjugates were used for the photoinactivation of fungi (C. albicans) and bacteria cells (E. coli). The Q band absorbances were the same for the Pc alone and when conjugated to AuNPs. The efficiency of these conjugates was evaluated by measuring the log reduction of the microorganisms (C. albicans and E. coli) after irradiation with visible light in the presence of photosensitizers. Aluminium phthalocyanine alone showed log 1.78 and log 2.51 reductions for C. albicans and E. coli respectively. However, the conjugates showed higher photosensitization with log 2.08 and log 3.34 for C. albicans and E. coli, respectively using 1–AuBPs. For complex 1–AuNRs log 2.53 and log 3.71 were achieved for C. albicans and E. coli respectively. The statistical analysis of the results showed that the enhanced photoinactivation observed in both microorganisms was irrespective of the shape of the nanoparticles conjugated. Photoinactivation of C. albicans was less than that of E. coli even though a higher concentration of complex 1 or its conjugates was used in C. albicans.
- Full Text:
- Authors: Mthethwa, Thandekile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189854 , vital:44940 , xlink:href="https://doi.org/10.1039/C4PP00315B"
- Description: The conjugates of aluminium phthalocyanine (complex 1) with gold nanorods (complex 1–AuNRs) and bipyramids (complex 1–AuBPs) showed improved singlet oxygen quantum yields of 0.23 and 0.24, respectively, compared to that of complex 1 alone at 0.12. Complex 1 and its conjugates were used for the photoinactivation of fungi (C. albicans) and bacteria cells (E. coli). The Q band absorbances were the same for the Pc alone and when conjugated to AuNPs. The efficiency of these conjugates was evaluated by measuring the log reduction of the microorganisms (C. albicans and E. coli) after irradiation with visible light in the presence of photosensitizers. Aluminium phthalocyanine alone showed log 1.78 and log 2.51 reductions for C. albicans and E. coli respectively. However, the conjugates showed higher photosensitization with log 2.08 and log 3.34 for C. albicans and E. coli, respectively using 1–AuBPs. For complex 1–AuNRs log 2.53 and log 3.71 were achieved for C. albicans and E. coli respectively. The statistical analysis of the results showed that the enhanced photoinactivation observed in both microorganisms was irrespective of the shape of the nanoparticles conjugated. Photoinactivation of C. albicans was less than that of E. coli even though a higher concentration of complex 1 or its conjugates was used in C. albicans.
- Full Text:
Photophysical and nonlinear optical studies of tetraakynyl zincphthalocyanine and its “clicked” analogue
- Bankole, Owolabi M, Nyokong, Tebello
- Authors: Bankole, Owolabi M , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189325 , vital:44837 , xlink:href="https://doi.org/10.1016/j.molstruc.2015.01.048"
- Description: We report here for the first time on the photophysical and nonlinear optical behavior of tetra-substituted alkynyl zinc phthalocyanine and its “clicked” analogue (4 and 5). The compounds exhibited high triplet quantum yields in dimethylsulphoxide (DMSO). Nonlinear optical (NLO) properties were also evaluated for the two compounds at 532 nm and 10 ns in DMSO. We observed two-photon absorption (2PA) and strong reverse saturable absorption (RSA) as the dominant mechanisms at nanosecond laser excitation. The presence of electron acceptor groups fused with triazole linkers in the peripheral positions of 4 provide excellent coexistent features, such as enhanced triplet quantum yields and lifetimes compared to 5. Large third-order susceptibility (2.09 × 10−11 and 3.53 × 10−9 esu) and hyperpolarizability (1.09 × 10−30 and 9.13 × 10−29 esu) were estimated for complexs 4 and 5, respectively.
- Full Text:
- Authors: Bankole, Owolabi M , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189325 , vital:44837 , xlink:href="https://doi.org/10.1016/j.molstruc.2015.01.048"
- Description: We report here for the first time on the photophysical and nonlinear optical behavior of tetra-substituted alkynyl zinc phthalocyanine and its “clicked” analogue (4 and 5). The compounds exhibited high triplet quantum yields in dimethylsulphoxide (DMSO). Nonlinear optical (NLO) properties were also evaluated for the two compounds at 532 nm and 10 ns in DMSO. We observed two-photon absorption (2PA) and strong reverse saturable absorption (RSA) as the dominant mechanisms at nanosecond laser excitation. The presence of electron acceptor groups fused with triazole linkers in the peripheral positions of 4 provide excellent coexistent features, such as enhanced triplet quantum yields and lifetimes compared to 5. Large third-order susceptibility (2.09 × 10−11 and 3.53 × 10−9 esu) and hyperpolarizability (1.09 × 10−30 and 9.13 × 10−29 esu) were estimated for complexs 4 and 5, respectively.
- Full Text:
Photophysical properties and photodynamic therapy effect of zinc phthalocyanine-spermine-single walled carbon nanotube conjugate on MCF-7 breast cancer cell line
- Ogbodu, Rachael O, Limson, Janice L, Prinsloo, Earl, Nyokong, Tebello
- Authors: Ogbodu, Rachael O , Limson, Janice L , Prinsloo, Earl , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189493 , vital:44851 , xlink:href="https://doi.org/10.1016/j.synthmet.2015.03.011"
- Description: The present study shows improved photodynamic therapy (PDT) effect of zinc mono carboxy phenoxy phthalocyanine (ZnMCPPc (1)) upon conjugation to spermine (via amide bond) as a targeting molecule on MCF-7 breast cancer cells. The ZnMCPPc-spermine (2) conjugate was adsorbed onto single walled carbon nanotubes (represented as ZnMCPPc-spermine-SWCNT (3)). There was no change in the fluorescence quantum yield of complex 1 following formation of 2 or 3. Complexes 2 and 3 showed improved photophysical properties; with over 50% increases in triplet and singlet oxygen quantum yields compared to 1. Complexes 1, 2 and 3 were relatively not toxic to MCF-7 cancer cells when incubated with 5–40 μM of each complex for 24 h in the dark. The PDT results showed that at 40 μM complex 1 resulted in only 64% decrease in cell viability, while 2 and 3 improved the PDT effect of 1 to 97% and 95% decrease in cell viability at 40 μM respectively.
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- Authors: Ogbodu, Rachael O , Limson, Janice L , Prinsloo, Earl , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189493 , vital:44851 , xlink:href="https://doi.org/10.1016/j.synthmet.2015.03.011"
- Description: The present study shows improved photodynamic therapy (PDT) effect of zinc mono carboxy phenoxy phthalocyanine (ZnMCPPc (1)) upon conjugation to spermine (via amide bond) as a targeting molecule on MCF-7 breast cancer cells. The ZnMCPPc-spermine (2) conjugate was adsorbed onto single walled carbon nanotubes (represented as ZnMCPPc-spermine-SWCNT (3)). There was no change in the fluorescence quantum yield of complex 1 following formation of 2 or 3. Complexes 2 and 3 showed improved photophysical properties; with over 50% increases in triplet and singlet oxygen quantum yields compared to 1. Complexes 1, 2 and 3 were relatively not toxic to MCF-7 cancer cells when incubated with 5–40 μM of each complex for 24 h in the dark. The PDT results showed that at 40 μM complex 1 resulted in only 64% decrease in cell viability, while 2 and 3 improved the PDT effect of 1 to 97% and 95% decrease in cell viability at 40 μM respectively.
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Photophysical properties gallium octacarboxy phthalocyanines conjugated to CdSe@ ZnS quantum dots
- Tshangana, Charmaine, Nyokong, Tebello
- Authors: Tshangana, Charmaine , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189055 , vital:44812 , xlink:href="https://doi.org/10.1016/j.saa.2015.06.086"
- Description: L-Glutathione (GSH) capped core CdSe (2.3 nm) and core shell CdSe@ZnS quantum dots (QDs) (3.0 nm and 3.5 nm) were coordinated to gallium octacarboxy phthalocyanine (ClGaPc(COOH)8) to form ClGaPc(COOH)8–QDs conjugates. An efficient transfer of energy from the QDs to the Pcs was demonstrated through Förster resonance energy transfer (FRET), the FRET efficiencies in all cases was above 50%. The photophysical parameters (triplet state and fluorescence quantum yields and lifetimes) were also determined for the conjugates. There was a decrease in the fluorescence lifetimes of ClGaPc(COOH)8 in the presence of all the QDs, due to the heavy atom effect. The triplet quantum yields increased in the conjugates. The lifetimes also became longer for the conjugates compared to Pc alone.
- Full Text:
- Authors: Tshangana, Charmaine , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189055 , vital:44812 , xlink:href="https://doi.org/10.1016/j.saa.2015.06.086"
- Description: L-Glutathione (GSH) capped core CdSe (2.3 nm) and core shell CdSe@ZnS quantum dots (QDs) (3.0 nm and 3.5 nm) were coordinated to gallium octacarboxy phthalocyanine (ClGaPc(COOH)8) to form ClGaPc(COOH)8–QDs conjugates. An efficient transfer of energy from the QDs to the Pcs was demonstrated through Förster resonance energy transfer (FRET), the FRET efficiencies in all cases was above 50%. The photophysical parameters (triplet state and fluorescence quantum yields and lifetimes) were also determined for the conjugates. There was a decrease in the fluorescence lifetimes of ClGaPc(COOH)8 in the presence of all the QDs, due to the heavy atom effect. The triplet quantum yields increased in the conjugates. The lifetimes also became longer for the conjugates compared to Pc alone.
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