An Assessment of the Effect of Rotenone on Selected Non-Target Aquatic Fauna
- Dalu, Tatenda, Wasserman, Ryan J, Jordaan, Martine, Froneman, P William, Froneman, Pierre William, Weyl, Olaf L F
- Authors: Dalu, Tatenda , Wasserman, Ryan J , Jordaan, Martine , Froneman, P William , Froneman, Pierre William , Weyl, Olaf L F
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124240 , vital:35579 , https://doi.org/10.1371/journal.pone.0142140.g001
- Description: Rotenone, a naturally occurring ketone, is widely employed for the management of invasive fish species. The use of rotenone poses serious challenges to conservation practitioners due to its impacts on non-target organisms including amphibians and macroinvertebrates. Using laboratory studies, we investigated the effects of different rotenone concentrations (0, 12.5, 25, 37.5, 50, 100 μg L-1) on selected invertebrate groups; Aeshnidae, Belostomatids, Decapods, Ephemeroptera, Pulmonata and zooplankton over a period of 18 hours. Based on field observations and body size, we hypothesized that Ephemeropterans and zooplank- ton would be more susceptible to rote none than Decapods, Belostomatids and snails. Experimental results supported this hypothesis and mortality and behaviour effects varied considerably between taxa, ranging from no effect (crab Potamonuates sidneyi) to 100% mortality (Daphnia pulex and Paradiaptomus lamellatus). Planktonic invertebrates were par- ticularly sensitive to rotenone even at very low concentrations. Future research should investigate the recovery time of invertebrate communities after the application of rotenone and conduct field assessments assessing the longer term effects of rotenone exposure on the population dynamics of those less sensitive organisms.
- Full Text:
- Date Issued: 2015
- Authors: Dalu, Tatenda , Wasserman, Ryan J , Jordaan, Martine , Froneman, P William , Froneman, Pierre William , Weyl, Olaf L F
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124240 , vital:35579 , https://doi.org/10.1371/journal.pone.0142140.g001
- Description: Rotenone, a naturally occurring ketone, is widely employed for the management of invasive fish species. The use of rotenone poses serious challenges to conservation practitioners due to its impacts on non-target organisms including amphibians and macroinvertebrates. Using laboratory studies, we investigated the effects of different rotenone concentrations (0, 12.5, 25, 37.5, 50, 100 μg L-1) on selected invertebrate groups; Aeshnidae, Belostomatids, Decapods, Ephemeroptera, Pulmonata and zooplankton over a period of 18 hours. Based on field observations and body size, we hypothesized that Ephemeropterans and zooplank- ton would be more susceptible to rote none than Decapods, Belostomatids and snails. Experimental results supported this hypothesis and mortality and behaviour effects varied considerably between taxa, ranging from no effect (crab Potamonuates sidneyi) to 100% mortality (Daphnia pulex and Paradiaptomus lamellatus). Planktonic invertebrates were par- ticularly sensitive to rotenone even at very low concentrations. Future research should investigate the recovery time of invertebrate communities after the application of rotenone and conduct field assessments assessing the longer term effects of rotenone exposure on the population dynamics of those less sensitive organisms.
- Full Text:
- Date Issued: 2015
Reflections on Teaching Africa in South Africa:
- Authors: Matthews, Sally
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142235 , vital:38061 , DOI: 10.1111/1467-9256.12107
- Description: This article draws on the author’s experience of teaching African Studies to undergraduate South African students in order to reflect on some of the key challenges facing teachers of African Studies, both in South Africa and beyond. In particular, it discusses challenges relating to teaching a field as contested as African Studies, looking at whether teaching African alternatives to mainstream African politics is helpful and at whether and how one can teach Africa in a way that encourages and develops critical thinking. The article also explores how the racial politics of the context in which one teaches African Studies inevitably affects the way in which students engage with the content of the course. While the article discusses these issues in relation to the South African higher education context in particular, implications for other contexts are also highlighted.
- Full Text:
- Date Issued: 2016
- Authors: Matthews, Sally
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142235 , vital:38061 , DOI: 10.1111/1467-9256.12107
- Description: This article draws on the author’s experience of teaching African Studies to undergraduate South African students in order to reflect on some of the key challenges facing teachers of African Studies, both in South Africa and beyond. In particular, it discusses challenges relating to teaching a field as contested as African Studies, looking at whether teaching African alternatives to mainstream African politics is helpful and at whether and how one can teach Africa in a way that encourages and develops critical thinking. The article also explores how the racial politics of the context in which one teaches African Studies inevitably affects the way in which students engage with the content of the course. While the article discusses these issues in relation to the South African higher education context in particular, implications for other contexts are also highlighted.
- Full Text:
- Date Issued: 2016
Making rules to live by: Was the proposed regulatory regime for invasive species reasonable? Perceptions of the South African trout industry
- Marire, Juniours, Snowball, Jeanette D, Fraser, Gavin C G
- Authors: Marire, Juniours , Snowball, Jeanette D , Fraser, Gavin C G
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68566 , vital:29285 , http://2015.essa.org.za/fullpaper/essa_2938.pdf
- Description: Publisher version , Despite considerable economic impact of trout-based aquaculture and recreational fishing, the Department of Environmental Affairs has been focusing almost entirely on ecological criteria in deciding the regulatory regime for trout. We examined whether the proposed regulatory regime for alien and invasive species that was published by the Department of Environmental Affairs in 2014 for public comment was reasonable. The analysis produced factors that might matter in the design of reasonable institutional arrangements that impose a reasonable regulatory burden on economic sectors utilising invasive species. We conducted factor analysis using an online survey that we conducted between May and July 2014. We obtained four clusters of factors: participatory policymaking, people-centeredness, credible scientific evidence for listing species as invasive and contextualisation of international evidence. We then utilised the factors in a logistic regression framework to assess their influence on the probability of perceiving the regulations to be reasonable. The likelihood of a trout sector player perceiving the regulations to be reasonable was 1.2%. We found that a one standard deviation increase in the “credibility of scientific evidence” increased the odds of perceiving the regulations to be reasonable by 1645%. A one standard deviation increase in “participation” increased the odds of perceiving the regulations to be reasonable by 410%. A one standard deviation increase in “people-centeredness” increased the odds of perceiving the regulations to be reasonable by 600%. Lastly, a one standard deviation increase in the variable “contextualising international evidence” increased the odds of perceiving the regulations to be reasonable by 415%. This research demonstrates that properly addressing the socioeconomic aspects of new policies in addition to ecological criteria makes it far more likely that stakeholders will regard them as reasonable, even if the new policies impose increased regulatory transaction cost burden on users or reduced access to a resource.
- Full Text:
- Date Issued: 2015
- Authors: Marire, Juniours , Snowball, Jeanette D , Fraser, Gavin C G
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68566 , vital:29285 , http://2015.essa.org.za/fullpaper/essa_2938.pdf
- Description: Publisher version , Despite considerable economic impact of trout-based aquaculture and recreational fishing, the Department of Environmental Affairs has been focusing almost entirely on ecological criteria in deciding the regulatory regime for trout. We examined whether the proposed regulatory regime for alien and invasive species that was published by the Department of Environmental Affairs in 2014 for public comment was reasonable. The analysis produced factors that might matter in the design of reasonable institutional arrangements that impose a reasonable regulatory burden on economic sectors utilising invasive species. We conducted factor analysis using an online survey that we conducted between May and July 2014. We obtained four clusters of factors: participatory policymaking, people-centeredness, credible scientific evidence for listing species as invasive and contextualisation of international evidence. We then utilised the factors in a logistic regression framework to assess their influence on the probability of perceiving the regulations to be reasonable. The likelihood of a trout sector player perceiving the regulations to be reasonable was 1.2%. We found that a one standard deviation increase in the “credibility of scientific evidence” increased the odds of perceiving the regulations to be reasonable by 1645%. A one standard deviation increase in “participation” increased the odds of perceiving the regulations to be reasonable by 410%. A one standard deviation increase in “people-centeredness” increased the odds of perceiving the regulations to be reasonable by 600%. Lastly, a one standard deviation increase in the variable “contextualising international evidence” increased the odds of perceiving the regulations to be reasonable by 415%. This research demonstrates that properly addressing the socioeconomic aspects of new policies in addition to ecological criteria makes it far more likely that stakeholders will regard them as reasonable, even if the new policies impose increased regulatory transaction cost burden on users or reduced access to a resource.
- Full Text:
- Date Issued: 2015
Secrets, lies and redemption:
- Boshoff, Priscilla A, Prinsloo, Jeanne
- Authors: Boshoff, Priscilla A , Prinsloo, Jeanne
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143381 , vital:38241 , DOI: 10.1080/00020184.2017.1285671
- Description: Confession is a central disciplining technology deployed in the second series of Intersexions, a popular South African TV series that seeks to change sexual and social behaviours that contribute to the risk of HIV infection. The article considers the ‘edu’ part of this edutainment programme, specifically with the nature of the lessons and with the form of ‘disciplining’ the narratives presuppose for gendered and sexual subjects. Central to this critical and constructivist exploration of the gender relationships that are validated and expurgated are Foucault’s notions of discourse and confession as a technology of self. We argue that the series presents a range of different gendered and sexual subjectivities but implicitly endorses a modern subjectivity and transformation at the level of the individual.
- Full Text:
- Date Issued: 2017
- Authors: Boshoff, Priscilla A , Prinsloo, Jeanne
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143381 , vital:38241 , DOI: 10.1080/00020184.2017.1285671
- Description: Confession is a central disciplining technology deployed in the second series of Intersexions, a popular South African TV series that seeks to change sexual and social behaviours that contribute to the risk of HIV infection. The article considers the ‘edu’ part of this edutainment programme, specifically with the nature of the lessons and with the form of ‘disciplining’ the narratives presuppose for gendered and sexual subjects. Central to this critical and constructivist exploration of the gender relationships that are validated and expurgated are Foucault’s notions of discourse and confession as a technology of self. We argue that the series presents a range of different gendered and sexual subjectivities but implicitly endorses a modern subjectivity and transformation at the level of the individual.
- Full Text:
- Date Issued: 2017
Histological validation of gonadal macroscopic staging criteria for Labeo cylindricus (Pisces: Cyprinidae)
- Booth, Anthony J, Weyl, Olaf L F
- Authors: Booth, Anthony J , Weyl, Olaf L F
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124593 , vital:35634 , https://doi.org/10.1080/15627020.2000.11657094
- Description: Histological examination of gametogenesis revealed that the current staging criteria used to assess gonadal recrudescence of the redeye labeo, Labeo cylindricus, were adequate. Gametogenesis was qualitatively similar to that of freshwater teleosts with a clearly defined seasonal reproductive cycle. L. cylindricus undergoes seasonal gross morphological and cytological gonadal changes with previtellogenesis dominating during the winter, vitellogenic development during spring and summer culminating in large-scale spawning at the end of summer. Post-spawning mass atresia of oocytes was evident in autumn. The histological data presented support macroscopical evidence that L. cylindricus is a synchronous iteroparous spawner, reproducing over a short period each year throughout its life-span.
- Full Text:
- Date Issued: 2010
- Authors: Booth, Anthony J , Weyl, Olaf L F
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124593 , vital:35634 , https://doi.org/10.1080/15627020.2000.11657094
- Description: Histological examination of gametogenesis revealed that the current staging criteria used to assess gonadal recrudescence of the redeye labeo, Labeo cylindricus, were adequate. Gametogenesis was qualitatively similar to that of freshwater teleosts with a clearly defined seasonal reproductive cycle. L. cylindricus undergoes seasonal gross morphological and cytological gonadal changes with previtellogenesis dominating during the winter, vitellogenic development during spring and summer culminating in large-scale spawning at the end of summer. Post-spawning mass atresia of oocytes was evident in autumn. The histological data presented support macroscopical evidence that L. cylindricus is a synchronous iteroparous spawner, reproducing over a short period each year throughout its life-span.
- Full Text:
- Date Issued: 2010
Human, vector and parasite Hsp90 proteins: a comparative bioinformatics analysis
- Faya, Ngonidzashe, Penkler, David L, Tastan Bishop, Özlem
- Authors: Faya, Ngonidzashe , Penkler, David L , Tastan Bishop, Özlem
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148038 , vital:38704 , DOI: 10.1016/j.fob.2015.11.003
- Description: The treatment of protozoan parasitic diseases is challenging, and thus identification and analysis of new drug targets is important. Parasites survive within host organisms, and some need intermediate hosts to complete their life cycle. Changing host environment puts stress on parasites, and often adaptation is accompanied by the expression of large amounts of heat shock proteins (Hsps). Among Hsps, Hsp90 proteins play an important role in stress environments. Yet, there has been little computational research on Hsp90 proteins to analyze them comparatively as potential parasitic drug targets. Here, an attempt was made to gain detailed insights into the differences between host, vector and parasitic Hsp90 proteins by large-scale bioinformatics analysis.
- Full Text:
- Date Issued: 2015
- Authors: Faya, Ngonidzashe , Penkler, David L , Tastan Bishop, Özlem
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148038 , vital:38704 , DOI: 10.1016/j.fob.2015.11.003
- Description: The treatment of protozoan parasitic diseases is challenging, and thus identification and analysis of new drug targets is important. Parasites survive within host organisms, and some need intermediate hosts to complete their life cycle. Changing host environment puts stress on parasites, and often adaptation is accompanied by the expression of large amounts of heat shock proteins (Hsps). Among Hsps, Hsp90 proteins play an important role in stress environments. Yet, there has been little computational research on Hsp90 proteins to analyze them comparatively as potential parasitic drug targets. Here, an attempt was made to gain detailed insights into the differences between host, vector and parasitic Hsp90 proteins by large-scale bioinformatics analysis.
- Full Text:
- Date Issued: 2015
Shifting white identities in South Africa: white Africanness and the struggle for racial justice
- Authors: Matthews, Sally
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142180 , vital:38056 , DOI: 10.25159/2413-3086/3821
- Description: The end of apartheid predictably caused something of an identity crisis for white South Africans. The sense of uncertainty about what it means to be white has led to much public debate about whiteness in South Africa, as well as a growing body of literature on whites in post-apartheid South Africa. One of the many responses to this need to rethink white identity has been the claim by some that white South Africans can be considered to be African or ought to begin to think of themselves as being African. This paper argues that whites' assertion of an African identity does not necessarily assist in the achievement of racial justice, but that some kind of shift in white identity is required in order for whites to be able to contribute to the achievement of a racially just South Africa. In making this argument, the paper brings contemporary discussions on race and whiteness, and in particular discussions about racial eliminativism, to bear on the question of whether or not white South Africans may rightly claim an African identity.
- Full Text:
- Date Issued: 2015
- Authors: Matthews, Sally
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142180 , vital:38056 , DOI: 10.25159/2413-3086/3821
- Description: The end of apartheid predictably caused something of an identity crisis for white South Africans. The sense of uncertainty about what it means to be white has led to much public debate about whiteness in South Africa, as well as a growing body of literature on whites in post-apartheid South Africa. One of the many responses to this need to rethink white identity has been the claim by some that white South Africans can be considered to be African or ought to begin to think of themselves as being African. This paper argues that whites' assertion of an African identity does not necessarily assist in the achievement of racial justice, but that some kind of shift in white identity is required in order for whites to be able to contribute to the achievement of a racially just South Africa. In making this argument, the paper brings contemporary discussions on race and whiteness, and in particular discussions about racial eliminativism, to bear on the question of whether or not white South Africans may rightly claim an African identity.
- Full Text:
- Date Issued: 2015
Shifting the priority from giving voice to listening: journalism new
- Garman, Anthea, Malila, Vanessa
- Authors: Garman, Anthea , Malila, Vanessa
- Date: 2015
- Language: English
- Type: text , article
- Identifier: vital:38355 , http://hdl.handle.net/10520/EJC175773
- Description: If, as the critics have argued, the South African media prioritise the voices of elite, middleclass South Africans, then the majority of South Africans are certainly invisible in the mainstream media. Kate Lacey argues that "listening is at the heart of what it means to be in the world, to be active, to be political" (2013: 163), and as such more than just providing a 'voice' for citizens, the media needs to be engaged in active listening to allow audiences to feel 'heard'. Servaes and Malikhao argue that people are 'voiceless' not because they have nothing to say, but because "nobody cares to listen to them" (2005: 91).
- Full Text:
- Date Issued: 2015
- Authors: Garman, Anthea , Malila, Vanessa
- Date: 2015
- Language: English
- Type: text , article
- Identifier: vital:38355 , http://hdl.handle.net/10520/EJC175773
- Description: If, as the critics have argued, the South African media prioritise the voices of elite, middleclass South Africans, then the majority of South Africans are certainly invisible in the mainstream media. Kate Lacey argues that "listening is at the heart of what it means to be in the world, to be active, to be political" (2013: 163), and as such more than just providing a 'voice' for citizens, the media needs to be engaged in active listening to allow audiences to feel 'heard'. Servaes and Malikhao argue that people are 'voiceless' not because they have nothing to say, but because "nobody cares to listen to them" (2005: 91).
- Full Text:
- Date Issued: 2015
The photophysical properties of multi-functional quantum dots-magnetic nanoparticles—indium octacarboxyphthalocyanine nanocomposite
- 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/10962/189876 , vital:44942 , xlink:href="https://doi.org/10.1007/s10895-014-1497-6"
- Description: This work presents the development of a multifunctional hybrid nanoparticle made of L-glutathione capped quantum dots (GSH-CdSe@ZnS), amino functionalized Fe3O4 magnetic nanoparticles and indium octacarboxy phthalocyanine (ClInPc(COOH)8). In this work we investigate the photophysical properties of the individual components and the hybrid nanoparticle, in addition we study the energy transfer (Förster Resonance Energy Transfer (FRET)) in the complex. FRET efficiencies of ~48 % were obtained for energy transfer between the QDs (when alone or linked to MNPs). Both triplet yields and lifetimes of ClInPc(COOH)8 increase in the nanocomposite, with a decrease in fluorescence lifetime. The hybrid nanoparticle showed improved photophysical properties and as a result can be used in photodynamic therapy.
- Full Text:
- Date Issued: 2015
- Authors: Tshangana, Charmaine , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189876 , vital:44942 , xlink:href="https://doi.org/10.1007/s10895-014-1497-6"
- Description: This work presents the development of a multifunctional hybrid nanoparticle made of L-glutathione capped quantum dots (GSH-CdSe@ZnS), amino functionalized Fe3O4 magnetic nanoparticles and indium octacarboxy phthalocyanine (ClInPc(COOH)8). In this work we investigate the photophysical properties of the individual components and the hybrid nanoparticle, in addition we study the energy transfer (Förster Resonance Energy Transfer (FRET)) in the complex. FRET efficiencies of ~48 % were obtained for energy transfer between the QDs (when alone or linked to MNPs). Both triplet yields and lifetimes of ClInPc(COOH)8 increase in the nanocomposite, with a decrease in fluorescence lifetime. The hybrid nanoparticle showed improved photophysical properties and as a result can be used in photodynamic therapy.
- Full Text:
- Date Issued: 2015
Physicochemical and photodynamic antimicrobial chemotherapy studies of mono-and tetra-pyridyloxy substituted indium (III) phthalocyanines
- Osifeko, Olawale, Durmus, Mahmut, Nyokong, Tebello
- Authors: Osifeko, Olawale , Durmus, Mahmut , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189547 , vital:44856 , xlink:href="https://doi.org/10.1016/j.jphotochem.2014.12.011"
- Description: The synthesis and photophysicochemical properties of mono- and tetra-pyridyloxy substituted indium(III) phthalocyanines (InPcs) are presented in this study. General trends are described for quantum yields of fluorescence, triplet, singlet oxygen and photodegradation as well as lifetimes of fluorescence and triplet state of these compounds. The complexes exhibited high singlet oxygen quantum yields (ФΔ) ranging from 0.44 to 0.66 in DMF, and from 0.44 to 0.69 in DMSO and ФΔ = 0.31 for the quartenized tetra substituted InPc which is soluble in water. The triplet quantum yields (ФT) ranged from 0.77 to 0.95 in DMF and from 0.77 to 0.94) in DMSO. The tetra substituted photosensitizers do not differ in their inactivation of bacteria with over 8 log reduction of viable bacteria when compared with the mono substituted photosensitizer which could only manage a 1 log reduction.
- Full Text:
- Date Issued: 2015
- Authors: Osifeko, Olawale , Durmus, Mahmut , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189547 , vital:44856 , xlink:href="https://doi.org/10.1016/j.jphotochem.2014.12.011"
- Description: The synthesis and photophysicochemical properties of mono- and tetra-pyridyloxy substituted indium(III) phthalocyanines (InPcs) are presented in this study. General trends are described for quantum yields of fluorescence, triplet, singlet oxygen and photodegradation as well as lifetimes of fluorescence and triplet state of these compounds. The complexes exhibited high singlet oxygen quantum yields (ФΔ) ranging from 0.44 to 0.66 in DMF, and from 0.44 to 0.69 in DMSO and ФΔ = 0.31 for the quartenized tetra substituted InPc which is soluble in water. The triplet quantum yields (ФT) ranged from 0.77 to 0.95 in DMF and from 0.77 to 0.94) in DMSO. The tetra substituted photosensitizers do not differ in their inactivation of bacteria with over 8 log reduction of viable bacteria when compared with the mono substituted photosensitizer which could only manage a 1 log reduction.
- Full Text:
- Date Issued: 2015
Dynamic mitochondrial localisation of STAT3 in the cellular adipogenesis model 3T3-L1:
- Kramer, Adam H, Edkins, Adrienne L, Hoppe, Heinrich C, Prinsloo, Earl
- Authors: Kramer, Adam H , Edkins, Adrienne L , Hoppe, Heinrich C , Prinsloo, Earl
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/164885 , vital:41181 , DOI: 10.1002/jcb.25076
- Description: A mechanistic relationship exists between protein localisation, activity and cellular differentiation. Understanding the contribution of these molecular mechanisms is required for elucidation of conditions that drive development. Literature suggests non‐canonical translocation of the Signal Transducer and Activator of Transcription 3 (STAT3) to the mitochondria contributes to the regulation of the electron transport chain, cellular respiration and reactive oxygen species production. Based on this we investigated the role of mitochondrial STAT3, specifically the serine 727 phosphorylated form, in cellular differentiation using the well‐defined mouse adipogenic model 3T3-L1.
- Full Text:
- Date Issued: 2015
- Authors: Kramer, Adam H , Edkins, Adrienne L , Hoppe, Heinrich C , Prinsloo, Earl
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/164885 , vital:41181 , DOI: 10.1002/jcb.25076
- Description: A mechanistic relationship exists between protein localisation, activity and cellular differentiation. Understanding the contribution of these molecular mechanisms is required for elucidation of conditions that drive development. Literature suggests non‐canonical translocation of the Signal Transducer and Activator of Transcription 3 (STAT3) to the mitochondria contributes to the regulation of the electron transport chain, cellular respiration and reactive oxygen species production. Based on this we investigated the role of mitochondrial STAT3, specifically the serine 727 phosphorylated form, in cellular differentiation using the well‐defined mouse adipogenic model 3T3-L1.
- Full Text:
- Date Issued: 2015
Wisdom as an aim of higher education
- Authors: Jones, Ward E
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/275765 , vital:55077 , xlink:href="https://doi.org/10.1007/s10790-014-9443-z"
- Description: A central concern of theoretical speculation about education is the kind of epistemic states that education can and should aim to achieve. One such epistemic state, long neglected in both education theory and philosophy, is wisdom. Might wisdom be something that educators should aim for? And might it be something that their students can achieve? My answer will be a qualified yes.
- Full Text:
- Date Issued: 2015
- Authors: Jones, Ward E
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/275765 , vital:55077 , xlink:href="https://doi.org/10.1007/s10790-014-9443-z"
- Description: A central concern of theoretical speculation about education is the kind of epistemic states that education can and should aim to achieve. One such epistemic state, long neglected in both education theory and philosophy, is wisdom. Might wisdom be something that educators should aim for? And might it be something that their students can achieve? My answer will be a qualified yes.
- Full Text:
- Date Issued: 2015
(Ferrocenylpyrazolyl) zinc (II) benzoates as catalysts for the ring opening polymerization of ε-caprolactone
- Obuah, Collins, Lochee, Yemanlall, Jordaan, Johan H L, Otto, Daniel P, Nyokong, Tebello, Darkwa, James
- Authors: Obuah, Collins , Lochee, Yemanlall , Jordaan, Johan H L , Otto, Daniel P , Nyokong, Tebello , Darkwa, James
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189515 , vital:44853 , xlink:href="https://doi.org/10.1016/j.poly.2015.02.007"
- Description: The reaction of Zn(OAc)2 and C6H5COOH or 3,5-NO2-C6H3COOH with 3-ferrocenylpyrazolyl-methylenepyridine (L1), 3-ferrocenyl-5-methylpyrazolyl-methylenepyridine (L2), 3-ferrocenylpyrazolyl-ethylamine (L3) and 3-ferrocenyl-5-pyrazolyl-ethylamine (L4) afford the corresponding complexes [Zn(C6H5COO)2(L1)] (1), [Zn(C6H5COO)2(L2)] (2), [Zn(3,5-NO2-C6H3COO)2(L1)] (3), [Zn(3,5-NO2-C6H3 COO)2(L2)] (4), [Zn(C6H5COO)2(L3)] (5), [Zn(C6H5COO)2(L4)] (6), [Zn(3,5-NO2-C6H3COO)2(L3)] (7) and [Zn(3,5-NO2-C6H3COO)2(L4)] (8). These complexes behave as catalysts for the ring opening polymerization of e-caprolactone to produce polymers with molecular weight that range from 1480 to 7080 g mol1 and exhibited moderate to broad PDIs. Evidence of these complexes acting as catalysts was obtained from both the polymerization data and kinetic studies. The polymerization data show that variation of the [CL]/[C] from 100 to 800 produced PCL with relatively the same molecular weight indicative of a catalyst behavior. The appearance of induction period in kinetic plots strengthens the fact that these complexes are catalysts rather than initiators. MALDI-TOF MS and 1 H NMR data show di-hydroxy end groups, which support the coordination mechanism rather than insertion mechanism. To understand the broad PDIs obtained for some of the polymer, the electronic properties of the zinc complexes were investigated using cyclic voltammetry. The results show that the zinc complexes containing amine based ligands are highly electrophilic therefore making them unstable, hence the broad PDIs observed for zinc complexes containing amine based ligands. Among the eight complexes investigated, complex 7 is the most active catalyst with kp value of 1.18 107 h1 mol1 at 110 C.
- Full Text:
- Date Issued: 2015
- Authors: Obuah, Collins , Lochee, Yemanlall , Jordaan, Johan H L , Otto, Daniel P , Nyokong, Tebello , Darkwa, James
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189515 , vital:44853 , xlink:href="https://doi.org/10.1016/j.poly.2015.02.007"
- Description: The reaction of Zn(OAc)2 and C6H5COOH or 3,5-NO2-C6H3COOH with 3-ferrocenylpyrazolyl-methylenepyridine (L1), 3-ferrocenyl-5-methylpyrazolyl-methylenepyridine (L2), 3-ferrocenylpyrazolyl-ethylamine (L3) and 3-ferrocenyl-5-pyrazolyl-ethylamine (L4) afford the corresponding complexes [Zn(C6H5COO)2(L1)] (1), [Zn(C6H5COO)2(L2)] (2), [Zn(3,5-NO2-C6H3COO)2(L1)] (3), [Zn(3,5-NO2-C6H3 COO)2(L2)] (4), [Zn(C6H5COO)2(L3)] (5), [Zn(C6H5COO)2(L4)] (6), [Zn(3,5-NO2-C6H3COO)2(L3)] (7) and [Zn(3,5-NO2-C6H3COO)2(L4)] (8). These complexes behave as catalysts for the ring opening polymerization of e-caprolactone to produce polymers with molecular weight that range from 1480 to 7080 g mol1 and exhibited moderate to broad PDIs. Evidence of these complexes acting as catalysts was obtained from both the polymerization data and kinetic studies. The polymerization data show that variation of the [CL]/[C] from 100 to 800 produced PCL with relatively the same molecular weight indicative of a catalyst behavior. The appearance of induction period in kinetic plots strengthens the fact that these complexes are catalysts rather than initiators. MALDI-TOF MS and 1 H NMR data show di-hydroxy end groups, which support the coordination mechanism rather than insertion mechanism. To understand the broad PDIs obtained for some of the polymer, the electronic properties of the zinc complexes were investigated using cyclic voltammetry. The results show that the zinc complexes containing amine based ligands are highly electrophilic therefore making them unstable, hence the broad PDIs observed for zinc complexes containing amine based ligands. Among the eight complexes investigated, complex 7 is the most active catalyst with kp value of 1.18 107 h1 mol1 at 110 C.
- Full Text:
- Date Issued: 2015
The intersection of culture and gender in constructions of ukuzila’ (spousal mourning) among AmaXhosa in the Eastern Cape:
- Ngqangweni, Hlonelwa, Macleod, Catriona I
- Authors: Ngqangweni, Hlonelwa , Macleod, Catriona I
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143615 , vital:38267 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: Mourning is a universal and culturally specific practice following the death of a significant other. The Xhosa equivalent of the mourning process is ukuzila. Very little has been written on the subject of ukuzila in spite of the detrimental effects of the practice on the widows’ health and safety, as well as the discriminatory nature of the practice. This paper presents the findings of a discourse analytic qualitative study conducted among isiXhosa speaking men and women in South Africa. The study revealed ukuzila as a practice put in place to show respect to the deceased. However, the showing of respect revealed a historically gendered cultural practice, imbued with power relations and centred on ‘visibility’. In light of this finding, the authors propose further research which includes exploring people’s willingness to change to a non-gendered practice of ukuzila, and alternate expressions of ukuzila that suit women rather than ‘culture’ and society.
- Full Text:
- Date Issued: 2015
- Authors: Ngqangweni, Hlonelwa , Macleod, Catriona I
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143615 , vital:38267 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: Mourning is a universal and culturally specific practice following the death of a significant other. The Xhosa equivalent of the mourning process is ukuzila. Very little has been written on the subject of ukuzila in spite of the detrimental effects of the practice on the widows’ health and safety, as well as the discriminatory nature of the practice. This paper presents the findings of a discourse analytic qualitative study conducted among isiXhosa speaking men and women in South Africa. The study revealed ukuzila as a practice put in place to show respect to the deceased. However, the showing of respect revealed a historically gendered cultural practice, imbued with power relations and centred on ‘visibility’. In light of this finding, the authors propose further research which includes exploring people’s willingness to change to a non-gendered practice of ukuzila, and alternate expressions of ukuzila that suit women rather than ‘culture’ and society.
- Full Text:
- Date Issued: 2015
All about the abs: discourse of health in the negotiation of masculine body-image
- Authors: Plüg, Simóne
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143793 , vital:38283 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: This paper explores contemporary South African masculinities and how aspects of consumer culture interweave the self and body-image where “the prime purpose of the maintenance of the inner body becomes the enhancement of the appearance of the outer body” (Featherstone, 1991, p. 171). It details a study of young men in Durban, using a qualitative research design and a social constructionist theoretical framework to explore the discourses participants use when discussing their own and other male bodies. It highlights the ways in which consumerism, the media, and other social dynamics promote and silence different discourses around what constitutes a desirable man in 21st century South Africa. The paper presents a detailed exploration of the ‘healthy body’ discourse, discussing how it shaped men’s engagement in self-sculpting practices and provided a means by which the participants came to understand and manage their gendered identities.
- Full Text:
- Date Issued: 2015
- Authors: Plüg, Simóne
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143793 , vital:38283 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: This paper explores contemporary South African masculinities and how aspects of consumer culture interweave the self and body-image where “the prime purpose of the maintenance of the inner body becomes the enhancement of the appearance of the outer body” (Featherstone, 1991, p. 171). It details a study of young men in Durban, using a qualitative research design and a social constructionist theoretical framework to explore the discourses participants use when discussing their own and other male bodies. It highlights the ways in which consumerism, the media, and other social dynamics promote and silence different discourses around what constitutes a desirable man in 21st century South Africa. The paper presents a detailed exploration of the ‘healthy body’ discourse, discussing how it shaped men’s engagement in self-sculpting practices and provided a means by which the participants came to understand and manage their gendered identities.
- Full Text:
- Date Issued: 2015
Privilege, solidarity and social justice struggles in South Africa: a view from Grahamstown
- Authors: Matthews, Sally
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142270 , vital:38064 , DOI:10.1353/trn.2015.0016
- Description: The last decade has seen a significant increase in the number and prominence of social movements in South Africa. Many of these movements are supported by relatively privileged individuals who are not themselves victims of the injustices the movements oppose. In this paper, I draw out some of the possibilities and limitations of the role of privileged individuals in supporting social movements struggling for social justice, looking particularly at the role of students in supporting such movements. The paper is based on research on the relationship between one such movement, the Unemployed People’s Movement (UPM), and a student organisation, the Students for Social Justice (SSJ), both of which are based in Grahamstown, South Africa. While acknowledging that privileged supporters of such movements can play a constructive role in social justice struggles, I use the experiences of the UPM and SSJ to explore some of the tensions that are likely to emerge and that need to be addressed when the relatively privileged participate in popular struggles. In particular, I discuss the likely difficulties privileged supporters will experience in bridging social divides and in contributing meaningfully to the theorisation of popular struggles.
- Full Text:
- Date Issued: 2015
- Authors: Matthews, Sally
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142270 , vital:38064 , DOI:10.1353/trn.2015.0016
- Description: The last decade has seen a significant increase in the number and prominence of social movements in South Africa. Many of these movements are supported by relatively privileged individuals who are not themselves victims of the injustices the movements oppose. In this paper, I draw out some of the possibilities and limitations of the role of privileged individuals in supporting social movements struggling for social justice, looking particularly at the role of students in supporting such movements. The paper is based on research on the relationship between one such movement, the Unemployed People’s Movement (UPM), and a student organisation, the Students for Social Justice (SSJ), both of which are based in Grahamstown, South Africa. While acknowledging that privileged supporters of such movements can play a constructive role in social justice struggles, I use the experiences of the UPM and SSJ to explore some of the tensions that are likely to emerge and that need to be addressed when the relatively privileged participate in popular struggles. In particular, I discuss the likely difficulties privileged supporters will experience in bridging social divides and in contributing meaningfully to the theorisation of popular struggles.
- Full Text:
- Date Issued: 2015
Visible Wars and Invisible Women: interrogating women's roles during wartime in Goretti Kyomuhendo's Waiting: a novel of Uganda at war
- Authors: Spencer, Lynda G
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/138880 , vital:37682 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC177790
- Description: Goretti Kyomuhendo's Waiting: A Novel of Uganda at War explores the atrocities that ordinary people experience during wartime by placing emphasis on the private suffering and humiliation inflicted on women in the domestic space of the home. This article argues that even if women do not actively feature on the battleground, they are still inadvertently drawn into the war, which has an adverse impact on their lives. Kyomuhendo draws on the experiences of different female characters to problematize the inherently ambiguous symbolic image of the mother, and shows that the violence performed on women's bodies is a result of the interplay between two hegemonic forces, patriarchal authority and state power.
- Full Text:
- Date Issued: 2015
- Authors: Spencer, Lynda G
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/138880 , vital:37682 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC177790
- Description: Goretti Kyomuhendo's Waiting: A Novel of Uganda at War explores the atrocities that ordinary people experience during wartime by placing emphasis on the private suffering and humiliation inflicted on women in the domestic space of the home. This article argues that even if women do not actively feature on the battleground, they are still inadvertently drawn into the war, which has an adverse impact on their lives. Kyomuhendo draws on the experiences of different female characters to problematize the inherently ambiguous symbolic image of the mother, and shows that the violence performed on women's bodies is a result of the interplay between two hegemonic forces, patriarchal authority and state power.
- Full Text:
- Date Issued: 2015
How general-purpose can a GPU be?
- Authors: Machanick, Philip
- Date: 2015
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61180 , vital:27988 , http://dx.doi.org/10.18489/sacj.v0i57.347
- Description: The use of graphics processing units (GPUs) in general-purpose computation (GPGPU) is a growing field. GPU instruction sets, while implementing a graphics pipeline, draw from a range of single instruction multiple datastream (SIMD) architectures characteristic of the heyday of supercomputers. Yet only one of these SIMD instruction sets has been of application on a wide enough range of problems to survive the era when the full range of supercomputer design variants was being explored: vector instructions. Supercomputers covered a range of exotic designs such as hypercubes and the Connection Machine (Fox, 1989). The latter is likely the source of the snide comment by Cray: it had thousands of relatively low-speed CPUs (Tucker & Robertson, 1988). Since Cray won, why are we not basing our ideas on his designs (Cray Inc., 2004), rather than those of the losers? The Top 500 supercomputer list is dominated by general-purpose CPUs, and nothing like the Connection Machine that headed the list in 1993 still exists.
- Full Text:
- Date Issued: 2015
- Authors: Machanick, Philip
- Date: 2015
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61180 , vital:27988 , http://dx.doi.org/10.18489/sacj.v0i57.347
- Description: The use of graphics processing units (GPUs) in general-purpose computation (GPGPU) is a growing field. GPU instruction sets, while implementing a graphics pipeline, draw from a range of single instruction multiple datastream (SIMD) architectures characteristic of the heyday of supercomputers. Yet only one of these SIMD instruction sets has been of application on a wide enough range of problems to survive the era when the full range of supercomputer design variants was being explored: vector instructions. Supercomputers covered a range of exotic designs such as hypercubes and the Connection Machine (Fox, 1989). The latter is likely the source of the snide comment by Cray: it had thousands of relatively low-speed CPUs (Tucker & Robertson, 1988). Since Cray won, why are we not basing our ideas on his designs (Cray Inc., 2004), rather than those of the losers? The Top 500 supercomputer list is dominated by general-purpose CPUs, and nothing like the Connection Machine that headed the list in 1993 still exists.
- Full Text:
- Date Issued: 2015
Subjective well-being in Africa
- Botha, Ferdi, Snowball, Jeanette D
- Authors: Botha, Ferdi , Snowball, Jeanette D
- Date: 2015
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61084 , vital:27946
- Description: Research on quality of life and subjective well-being (SWB) has witnessed a remarkable growth over the past four decades or so. Since Easterlin’s (1974) seminal contribution on the relationship between happiness and income, thousands of studies have followed that examine the intricacies of subjective well-being (for reviews, see Frey and Stutzer, 2002; Dolan et al., 2008; MacKerron, 2012). These studies have uncovered some very important aspects of individual well-being and have pointed to the fact that money or income is not always (as is often assumed) the most important determinant of SWB.
- Full Text:
- Date Issued: 2015
- Authors: Botha, Ferdi , Snowball, Jeanette D
- Date: 2015
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61084 , vital:27946
- Description: Research on quality of life and subjective well-being (SWB) has witnessed a remarkable growth over the past four decades or so. Since Easterlin’s (1974) seminal contribution on the relationship between happiness and income, thousands of studies have followed that examine the intricacies of subjective well-being (for reviews, see Frey and Stutzer, 2002; Dolan et al., 2008; MacKerron, 2012). These studies have uncovered some very important aspects of individual well-being and have pointed to the fact that money or income is not always (as is often assumed) the most important determinant of SWB.
- Full Text:
- Date Issued: 2015
Visible light transformation of Rhodamine 6G using tetracarbazole zinc phthalocyanine when embedded in electrospun fibers and in the presence of ZnO and Ag particles
- 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/10962/189456 , vital:44848 , xlink:href="https://doi.org/10.1080/00958972.2015.1013944"
- Description: Herein, we report the photocatalytic transformation of Rhodamine 6G (Rh 6G) using tetracarbazole zinc phthalocyanine (TCbZnPc) when alone or when conjugated with ZnO macroparticles (ZnOMPs) and silver nanoparticles (AgNPs), represented as TCbZnPc–ZnOMPs and TCbZnPc–AgNPs, respectively. The photocatalysts were supported onto electrospun polystyrene fibers. The efficiency of TCbZnPc was improved by the presence of both ZnOMPs and AgNPs. HPLC equipped with UV–vis was used to study phototransformation products. The mechanism of transformation was via the N-de-ethylation of Rh 6G.
- Full Text:
- Date Issued: 2015
- Authors: Khoza, Phindile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189456 , vital:44848 , xlink:href="https://doi.org/10.1080/00958972.2015.1013944"
- Description: Herein, we report the photocatalytic transformation of Rhodamine 6G (Rh 6G) using tetracarbazole zinc phthalocyanine (TCbZnPc) when alone or when conjugated with ZnO macroparticles (ZnOMPs) and silver nanoparticles (AgNPs), represented as TCbZnPc–ZnOMPs and TCbZnPc–AgNPs, respectively. The photocatalysts were supported onto electrospun polystyrene fibers. The efficiency of TCbZnPc was improved by the presence of both ZnOMPs and AgNPs. HPLC equipped with UV–vis was used to study phototransformation products. The mechanism of transformation was via the N-de-ethylation of Rh 6G.
- Full Text:
- Date Issued: 2015