Unquenched fluorescence lifetime for β-phenylthio substituted zinc phthalocyanine upon conjugation to gold nanoparticles
- Forteath, Shaun, Antunes, Edith M, Chidawanyika, Wadzanai J U, Nyokong, Tebello
- Authors: Forteath, Shaun , Antunes, Edith M , Chidawanyika, Wadzanai J U , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245774 , vital:51404 , xlink:href="https://doi.org/10.1016/j.poly.2011.12.015"
- Description: Photoinduced processes in phthalocyanine-functionalized gold nanoparticles have been investigated by spectroscopic measurements. The zinc phthalocyanine used contained four phenylthio peripheral substituents (ZnPc(SPh)4). The conjugates formed are represented as ZnPc(SPh)4–AuNP. The absorption spectrum of the ZnPc(SPh)4–AuNP shows a broadening of the phthalocyanine Q-band absorption, probably due to a tight packing of the phthalocyanines on the gold nanoparticle surface. For the attached phthalocyanines, the two fluorescence lifetimes obtained by time-correlated single photon counting (TCSPC) were determined to be both longer and shorter than that of the free Pc. The fluorescence lifetimes were resolved using time resolved fluorescence spectroscopy (TRES).
- Full Text:
- Date Issued: 2012
- Authors: Forteath, Shaun , Antunes, Edith M , Chidawanyika, Wadzanai J U , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245774 , vital:51404 , xlink:href="https://doi.org/10.1016/j.poly.2011.12.015"
- Description: Photoinduced processes in phthalocyanine-functionalized gold nanoparticles have been investigated by spectroscopic measurements. The zinc phthalocyanine used contained four phenylthio peripheral substituents (ZnPc(SPh)4). The conjugates formed are represented as ZnPc(SPh)4–AuNP. The absorption spectrum of the ZnPc(SPh)4–AuNP shows a broadening of the phthalocyanine Q-band absorption, probably due to a tight packing of the phthalocyanines on the gold nanoparticle surface. For the attached phthalocyanines, the two fluorescence lifetimes obtained by time-correlated single photon counting (TCSPC) were determined to be both longer and shorter than that of the free Pc. The fluorescence lifetimes were resolved using time resolved fluorescence spectroscopy (TRES).
- Full Text:
- Date Issued: 2012
Violence and the cultural logics of pain: representations of sexuality in the work of Nicholas Hlobo and Zanele Muholi
- Authors: Makhubu, Nomusa
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147814 , vital:38675 , https://0-doi.org.wam.seals.ac.za/10.1080/02560046.2012.723843
- Description: Nicholas Hlobo and Zanele Muholi have raised critical issues regarding sexual identity in patriarchal contexts since they premiered at the Michael Stevenson Gallery in 2005. Nicholas Hlobo, a sculptor and performance artist, and Zanele Muholi, a photographer and activist, explore different ways of representing sexuality – in particular, homosexuality. Hlobo investigates notions of masculinity and the practice of circumcision, while Muholi documents the existence of transgender and homosexuality in township spaces (her recent work expands to various other spaces). This article focuses on the roles that violence plays in the sexual politics represented in Hlobo and Muholi’s work.
- Full Text:
- Date Issued: 2012
- Authors: Makhubu, Nomusa
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147814 , vital:38675 , https://0-doi.org.wam.seals.ac.za/10.1080/02560046.2012.723843
- Description: Nicholas Hlobo and Zanele Muholi have raised critical issues regarding sexual identity in patriarchal contexts since they premiered at the Michael Stevenson Gallery in 2005. Nicholas Hlobo, a sculptor and performance artist, and Zanele Muholi, a photographer and activist, explore different ways of representing sexuality – in particular, homosexuality. Hlobo investigates notions of masculinity and the practice of circumcision, while Muholi documents the existence of transgender and homosexuality in township spaces (her recent work expands to various other spaces). This article focuses on the roles that violence plays in the sexual politics represented in Hlobo and Muholi’s work.
- Full Text:
- Date Issued: 2012
Vulindela!: opening the gates of journalism
- Authors: Schoon, Alette
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159528 , vital:40305 , https://hdl.handle.net/10520/EJC134094
- Description: A group of teenagers crowd together in a hall in Fingo Village, Grahamstown. They listen with rapt attention as one of them shares his anger at being short-changed in terms of his own future - teachers are absent for two out of every six school periods, compromising his chances of education.
- Full Text:
- Date Issued: 2012
- Authors: Schoon, Alette
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159528 , vital:40305 , https://hdl.handle.net/10520/EJC134094
- Description: A group of teenagers crowd together in a hall in Fingo Village, Grahamstown. They listen with rapt attention as one of them shares his anger at being short-changed in terms of his own future - teachers are absent for two out of every six school periods, compromising his chances of education.
- Full Text:
- Date Issued: 2012
What's been built in twenty years?: SADC and Southern Africa's political and regional security culture
- Authors: Bischoff, Paul, 1954-
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/161498 , vital:40633
- Description: The sense of region in Southern Africa is based on nationalism and its struggles for national liberation. Unusually, the norms of smaller states initially shaped the region's scope and culture of interaction. First and foremost, cooperation happened in the area of security, an initial focus being to uphold the independence and sovereignty of the state in the face of challenges from apartheid South Africa. As such, rather atypically, intergovernmental security cooperation preceded broad based economic cooperation. This has meant that security and development have remained largely de-linked and this has helped discourage implementing a society or human rights centred approach to security. Cooperation has been made more difficult by disparate political systems with divergent values, cultures, agendas and sensibilities. As such, regionalism reinforces nationalism to the exclusion of development or wider notions of political and social security. The region amounts to a security regime with only a patchy record in advancing security. Therefore, in the face of developmental challenges and unless a degree of strategic coherence along political and policy fronts is reached, after 20 years of SADC the endeavour to institutionalise security in conventional state-centred ways amounts to a scenario of diminishing returns.
- Full Text:
- Date Issued: 2012
- Authors: Bischoff, Paul, 1954-
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/161498 , vital:40633
- Description: The sense of region in Southern Africa is based on nationalism and its struggles for national liberation. Unusually, the norms of smaller states initially shaped the region's scope and culture of interaction. First and foremost, cooperation happened in the area of security, an initial focus being to uphold the independence and sovereignty of the state in the face of challenges from apartheid South Africa. As such, rather atypically, intergovernmental security cooperation preceded broad based economic cooperation. This has meant that security and development have remained largely de-linked and this has helped discourage implementing a society or human rights centred approach to security. Cooperation has been made more difficult by disparate political systems with divergent values, cultures, agendas and sensibilities. As such, regionalism reinforces nationalism to the exclusion of development or wider notions of political and social security. The region amounts to a security regime with only a patchy record in advancing security. Therefore, in the face of developmental challenges and unless a degree of strategic coherence along political and policy fronts is reached, after 20 years of SADC the endeavour to institutionalise security in conventional state-centred ways amounts to a scenario of diminishing returns.
- Full Text:
- Date Issued: 2012
White anti-racism in post-apartheid South Africa:
- Authors: Matthews, Sally
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142361 , vital:38073 , DOI: 10.1080/02589346.2012.683938
- Description: South Africans today live not only with the memory of the racial injustices of the past, but also with present injustices that are a consequence of that past. How should white South Africans live with these past and present injustices? On recognition of the racial injustices of the past and of the continuation of forms of white privilege today, involvement in ongoing anti-racist struggles seems to be an appropriate way for white South Africans to respond to past and present injustices. However, some discussions of the way in which white privilege operates and is perpetuated in post-segregationist societies suggest the need for caution with regard to white involvement in anti-racist struggles, arguing that some of the ways in which white people involve themselves in apparently anti-racist work actually result in the perpetuation rather than the erosion of white privilege. This article explores concerns about the intractability of white privilege while also ultimately defending the appropriateness of white involvement in anti-racist struggles.
- Full Text:
- Date Issued: 2012
- Authors: Matthews, Sally
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142361 , vital:38073 , DOI: 10.1080/02589346.2012.683938
- Description: South Africans today live not only with the memory of the racial injustices of the past, but also with present injustices that are a consequence of that past. How should white South Africans live with these past and present injustices? On recognition of the racial injustices of the past and of the continuation of forms of white privilege today, involvement in ongoing anti-racist struggles seems to be an appropriate way for white South Africans to respond to past and present injustices. However, some discussions of the way in which white privilege operates and is perpetuated in post-segregationist societies suggest the need for caution with regard to white involvement in anti-racist struggles, arguing that some of the ways in which white people involve themselves in apparently anti-racist work actually result in the perpetuation rather than the erosion of white privilege. This article explores concerns about the intractability of white privilege while also ultimately defending the appropriateness of white involvement in anti-racist struggles.
- Full Text:
- Date Issued: 2012
Working with cultural-historical activity theory and critical realism to investigate and expand farmer learning in Southern Africa
- Mukute, Mutizwa, Lotz-Sisitka, Heila
- Authors: Mukute, Mutizwa , Lotz-Sisitka, Heila
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182494 , vital:43835 , xlink:href="https://doi.org/10.1080/10749039.2012.656173"
- Description: This article uses the theoretical and methodological tools of cultural historical activity theory and critical realism to examine three case studies of the introduction and expansion of sustainable agricultural practices in southern Africa. The article addresses relevant issues in the field of agricultural extension, which lacks a theoretical “bridge” between top-down knowledge transfer and bottom-up participatory approaches to learning. Further, the article considers the learning environments necessary for sustainable agriculture. Such environments provided research participants with encounters with “postnormal” scientific practices that recognise and engage plural ways of knowing. Our research explored why farmers learn and practise sustainable agriculture, how they learn and practise it, the contradictions they are facing, and how these contradictions can be overcome in a context of change-oriented learning.
- Full Text:
- Date Issued: 2012
- Authors: Mukute, Mutizwa , Lotz-Sisitka, Heila
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182494 , vital:43835 , xlink:href="https://doi.org/10.1080/10749039.2012.656173"
- Description: This article uses the theoretical and methodological tools of cultural historical activity theory and critical realism to examine three case studies of the introduction and expansion of sustainable agricultural practices in southern Africa. The article addresses relevant issues in the field of agricultural extension, which lacks a theoretical “bridge” between top-down knowledge transfer and bottom-up participatory approaches to learning. Further, the article considers the learning environments necessary for sustainable agriculture. Such environments provided research participants with encounters with “postnormal” scientific practices that recognise and engage plural ways of knowing. Our research explored why farmers learn and practise sustainable agriculture, how they learn and practise it, the contradictions they are facing, and how these contradictions can be overcome in a context of change-oriented learning.
- Full Text:
- Date Issued: 2012
Shaking a hornets' nest: pitfalls of abortion counselling in a secular constitutional order–a view from South Africa
- Authors: Vincent, Louise
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141521 , vital:37982 , DOI: 10.1080/13691058.2011.627469
- Description: There exists an enormous gulf between the aspirations of South Africa's abortion legislation – among the most liberal in the world – and its implementation. One weakness in the provision of abortion services in South Africa is the absence of comprehensive abortion counselling services. On the face of it, the idea that counselling ought, as a matter of course, to be a significant component of a country's termination of pregnancy service provision, seems both straightforwardly sensible and politically innocent. This paper describes how abortion counselling has historically, in many different contexts, been saturated with questionable assumptions about women and their bodies. Counselling has more often than not been deployed, either as the formal policy of states or through informal mechanisms, as a means of curbing the right to abortion rather than deepening the meaning of that right. Differing approaches to counselling emerge as a reflection of contestations over reproductive and gender politics. Specifying an appropriate model for the provision of state-sponsored abortion counselling in the public health sector of a secular constitutional state provokes more of a hornet's nest of dilemmas than is sometimes supposed.
- Full Text:
- Date Issued: 2011
- Authors: Vincent, Louise
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141521 , vital:37982 , DOI: 10.1080/13691058.2011.627469
- Description: There exists an enormous gulf between the aspirations of South Africa's abortion legislation – among the most liberal in the world – and its implementation. One weakness in the provision of abortion services in South Africa is the absence of comprehensive abortion counselling services. On the face of it, the idea that counselling ought, as a matter of course, to be a significant component of a country's termination of pregnancy service provision, seems both straightforwardly sensible and politically innocent. This paper describes how abortion counselling has historically, in many different contexts, been saturated with questionable assumptions about women and their bodies. Counselling has more often than not been deployed, either as the formal policy of states or through informal mechanisms, as a means of curbing the right to abortion rather than deepening the meaning of that right. Differing approaches to counselling emerge as a reflection of contestations over reproductive and gender politics. Specifying an appropriate model for the provision of state-sponsored abortion counselling in the public health sector of a secular constitutional state provokes more of a hornet's nest of dilemmas than is sometimes supposed.
- Full Text:
- Date Issued: 2011
Cross-cultural communication in a north-eastern Cape farming community:
- Authors: Kaschula, Russell H
- Date: 1989
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175313 , vital:42564 , https://doi.org/10.1080/02572117.1989.10586786
- Description: Cross-cultural communication is dealt with and more specifically, the communicative competence of 15 white English-speaking farmers when they speak Xhosa to their labourers is assessed. This research was conducted in the Elliot, Ugie, and Maclear areas of the north-eastern Cape. A broad sociolinguistic framework drawing on both ethnographic and ethnomethodological principles was used; complications caused by cross-cultural differences which are reflected in language, and which may lead to possible communication breakdown, were isolated. The actual analysis of speech in terms of ethnomethodological principles, such as turn-taking and the co-operative principle, was undertaken.
- Full Text:
- Date Issued: 1989
- Authors: Kaschula, Russell H
- Date: 1989
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175313 , vital:42564 , https://doi.org/10.1080/02572117.1989.10586786
- Description: Cross-cultural communication is dealt with and more specifically, the communicative competence of 15 white English-speaking farmers when they speak Xhosa to their labourers is assessed. This research was conducted in the Elliot, Ugie, and Maclear areas of the north-eastern Cape. A broad sociolinguistic framework drawing on both ethnographic and ethnomethodological principles was used; complications caused by cross-cultural differences which are reflected in language, and which may lead to possible communication breakdown, were isolated. The actual analysis of speech in terms of ethnomethodological principles, such as turn-taking and the co-operative principle, was undertaken.
- Full Text:
- Date Issued: 1989