The hermeneutics of recovery
- Kong, Camillia, Campbell, Megan M, Kpobi, Lily, Swartz, Leslie, Atuire, Caesar
- Authors: Kong, Camillia , Campbell, Megan M , Kpobi, Lily , Swartz, Leslie , Atuire, Caesar
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/302554 , vital:58207 , xlink:href="https://doi.org/10.1177/13634615211000549"
- Description: The widespread use of faith-based and traditional healing for mental disorders within African contexts is well known. However, normative responses tend to fall within two camps: on one hand, those oriented towards the biomedical model of psychiatry stress the abuses and superstition of such healing, whilst critics adopting a more ‘local’ perspective have fundamentally challenged the universalist claims of biomedical diagnostic categories and psychiatric treatments. What seemingly emerges is a dichotomy between those who endorse more ‘universalist’ or ‘relativist’ approaches as an analytical lens to the challenges of the diverse healing strands within African contexts. In this article, we draw upon the resources of philosophy and existing empirical work to challenge the notion that constructive dialogue cannot be had between seemingly incommensurable healing practices in global mental health. First, we suggest the need for much-needed conceptual clarity to explore the hermeneutics of meaning, practice, and understanding, in order to forge constructive normative pathways of dialogue between seemingly incommensurable values and conceptual schemas around mental disorder and healing. Second, we contextualise the complex motives to emphasise difference amongst health practitioners within a competitive healing economy. Finally, we appeal to the notion of recovery as discovery as a fruitful conceptual framework which incorporates dialogue, comparative evaluation, and cross-cultural enrichment across divergent conceptualisations of mental health.
- Full Text:
- Date Issued: 2021
- Authors: Kong, Camillia , Campbell, Megan M , Kpobi, Lily , Swartz, Leslie , Atuire, Caesar
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/302554 , vital:58207 , xlink:href="https://doi.org/10.1177/13634615211000549"
- Description: The widespread use of faith-based and traditional healing for mental disorders within African contexts is well known. However, normative responses tend to fall within two camps: on one hand, those oriented towards the biomedical model of psychiatry stress the abuses and superstition of such healing, whilst critics adopting a more ‘local’ perspective have fundamentally challenged the universalist claims of biomedical diagnostic categories and psychiatric treatments. What seemingly emerges is a dichotomy between those who endorse more ‘universalist’ or ‘relativist’ approaches as an analytical lens to the challenges of the diverse healing strands within African contexts. In this article, we draw upon the resources of philosophy and existing empirical work to challenge the notion that constructive dialogue cannot be had between seemingly incommensurable healing practices in global mental health. First, we suggest the need for much-needed conceptual clarity to explore the hermeneutics of meaning, practice, and understanding, in order to forge constructive normative pathways of dialogue between seemingly incommensurable values and conceptual schemas around mental disorder and healing. Second, we contextualise the complex motives to emphasise difference amongst health practitioners within a competitive healing economy. Finally, we appeal to the notion of recovery as discovery as a fruitful conceptual framework which incorporates dialogue, comparative evaluation, and cross-cultural enrichment across divergent conceptualisations of mental health.
- Full Text:
- Date Issued: 2021
The role of mass-rearing in weed biological control projects in South Africa
- Hill, Martin P, Conlong, Desmond, Zachariades, Costas, Coetzee, Julie A, Paterson, Iain D, Miller, Benjamin E, Foxcroft, Llewellyn, van der Westhuizen, L
- Authors: Hill, Martin P , Conlong, Desmond , Zachariades, Costas , Coetzee, Julie A , Paterson, Iain D , Miller, Benjamin E , Foxcroft, Llewellyn , van der Westhuizen, L
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/407094 , vital:70335 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v29_n3_a22"
- Description: It has been documented that the continual release of high numbers of biological control (biocontrol) agents for weeds increases the likelihood of agent establishment and has been shown to reduce the time between the first release and subsequent control of the target weed. Here we review the mass-rearing activities for weed biocontrol agents in South Africa between 2011 and 2020. Some 4.7 million individual insects from 40 species of biocontrol agent have been released on 31 weed species at over 2000 sites throughout South Africa during the last decade. These insects were produced at mass-rearing facilities at eight research institutions, five schools and 10 Non-Governmental Organizations. These mass-rearing activities have created employment for 41 fulltime, fixed contract staff, of which 11 are people living with physical disabilities. To improve the uptake of mass-rearing through community engagement, appropriate protocols are required to ensure that agents are produced in high numbers to suppress invasive alien plant populations in South Africa.
- Full Text:
- Date Issued: 2021
- Authors: Hill, Martin P , Conlong, Desmond , Zachariades, Costas , Coetzee, Julie A , Paterson, Iain D , Miller, Benjamin E , Foxcroft, Llewellyn , van der Westhuizen, L
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/407094 , vital:70335 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v29_n3_a22"
- Description: It has been documented that the continual release of high numbers of biological control (biocontrol) agents for weeds increases the likelihood of agent establishment and has been shown to reduce the time between the first release and subsequent control of the target weed. Here we review the mass-rearing activities for weed biocontrol agents in South Africa between 2011 and 2020. Some 4.7 million individual insects from 40 species of biocontrol agent have been released on 31 weed species at over 2000 sites throughout South Africa during the last decade. These insects were produced at mass-rearing facilities at eight research institutions, five schools and 10 Non-Governmental Organizations. These mass-rearing activities have created employment for 41 fulltime, fixed contract staff, of which 11 are people living with physical disabilities. To improve the uptake of mass-rearing through community engagement, appropriate protocols are required to ensure that agents are produced in high numbers to suppress invasive alien plant populations in South Africa.
- Full Text:
- Date Issued: 2021
Visible light responsive TiO2-graphene oxide nanosheets-Zn phthalocyanine ternary heterojunction assisted photoelectrocatalytic degradation of Orange G
- Nwahara, Nnamdi, Adeniyi, Omotayo, Mashazi, Philani N, Nyokong, Tebello
- Authors: Nwahara, Nnamdi , Adeniyi, Omotayo , Mashazi, Philani N , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185446 , vital:44387 , xlink:href="https://doi.org/10.1016/j.jphotochem.2021.113291"
- Description: Herein, we report on the successful fabrication of a visible light-responsive TiO2 - graphene oxide nanosheets – Zn phthalocyanine (TiO2@GONS@ZnPc) ternary structure for the photoelectrochemical degradation of Orange G azo dye. The characterization of TiO2@GONS@ZnPc composite was achieved using various spectroscopic and microscopic techniques. Our results show that the TiO2@GONS@ZnPc surface hybrid heterojunction promotes charge separation and electron migration, significantly improving the degradation efficiency with an applied potential. For the first time, we show the existence of a non-radical activation route for persulfate (PS) using such π electron-rich ZnPc-GONS catalysts. The degradation kinetics were found to follow pseudo first order kinetics. Electron spin resonance analyses suggested that neither hydroxyl radicals nor sulfate radicals were produced therein, and therefore were not responsible for the persulfate-driven oxidation of the OG dye. These findings suggest that both which GONS and ZnPc play a critical role in mediating the eventual charge transfer mediated PS activation. The results illustrate the remarkable capacity of the TiO2@GONS@ZnPc composite to rapidly degrade Orange G by a coupled TiO2@GONS@ZnPc-persulfate system.
- Full Text:
- Date Issued: 2021
- Authors: Nwahara, Nnamdi , Adeniyi, Omotayo , Mashazi, Philani N , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185446 , vital:44387 , xlink:href="https://doi.org/10.1016/j.jphotochem.2021.113291"
- Description: Herein, we report on the successful fabrication of a visible light-responsive TiO2 - graphene oxide nanosheets – Zn phthalocyanine (TiO2@GONS@ZnPc) ternary structure for the photoelectrochemical degradation of Orange G azo dye. The characterization of TiO2@GONS@ZnPc composite was achieved using various spectroscopic and microscopic techniques. Our results show that the TiO2@GONS@ZnPc surface hybrid heterojunction promotes charge separation and electron migration, significantly improving the degradation efficiency with an applied potential. For the first time, we show the existence of a non-radical activation route for persulfate (PS) using such π electron-rich ZnPc-GONS catalysts. The degradation kinetics were found to follow pseudo first order kinetics. Electron spin resonance analyses suggested that neither hydroxyl radicals nor sulfate radicals were produced therein, and therefore were not responsible for the persulfate-driven oxidation of the OG dye. These findings suggest that both which GONS and ZnPc play a critical role in mediating the eventual charge transfer mediated PS activation. The results illustrate the remarkable capacity of the TiO2@GONS@ZnPc composite to rapidly degrade Orange G by a coupled TiO2@GONS@ZnPc-persulfate system.
- Full Text:
- Date Issued: 2021
A comparative study of the effect of different stabilizers on the critical quality attributes of self-assembling nano co-crystals
- Witika, Bwalya A, Smith, Vincent J, Walker, Roderick B
- Authors: Witika, Bwalya A , Smith, Vincent J , Walker, Roderick B
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183224 , vital:43931 , xlink:href=" https://doi.org/10.3390/pharmaceutics12020182"
- Description: Lamivudine (3TC) and zidovudine (AZT) are antiviral agents used orally to manage HIV/AIDS infection. A pseudo one-solvent bottom-up approach was used to develop and produce nano co-crystals of 3TC and AZT. Equimolar amounts of 3TC dissolved in de-ionized water and AZT in methanol were rapidly injected into a pre-cooled vessel and sonicated at 4 °C. The resultant suspensions were characterized using a Zetasizer. The particle size, polydispersity index and Zeta potential were elucidated. Further characterization was undertaken using powder X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and energy dispersive X-ray spectroscopy scanning electron microscopy. Different surfactants were assessed for their ability to stabilize the nano co-crystals and for their ability to produce nano co-crystals with specific and desirable critical quality attributes (CQA) including particle size (PS) less than 1000 nm, polydispersity index (PDI) less than 0.500 and Zeta potential (ZP) less than −30 mV. All surfactants produced co-crystals in the nanometer range. The PDI and PS are concentration-dependent for all nano co-crystals manufactured while only ZP was within specification when sodium dodecyl sulfate was used in the process.
- Full Text:
- Date Issued: 2020
- Authors: Witika, Bwalya A , Smith, Vincent J , Walker, Roderick B
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183224 , vital:43931 , xlink:href=" https://doi.org/10.3390/pharmaceutics12020182"
- Description: Lamivudine (3TC) and zidovudine (AZT) are antiviral agents used orally to manage HIV/AIDS infection. A pseudo one-solvent bottom-up approach was used to develop and produce nano co-crystals of 3TC and AZT. Equimolar amounts of 3TC dissolved in de-ionized water and AZT in methanol were rapidly injected into a pre-cooled vessel and sonicated at 4 °C. The resultant suspensions were characterized using a Zetasizer. The particle size, polydispersity index and Zeta potential were elucidated. Further characterization was undertaken using powder X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and energy dispersive X-ray spectroscopy scanning electron microscopy. Different surfactants were assessed for their ability to stabilize the nano co-crystals and for their ability to produce nano co-crystals with specific and desirable critical quality attributes (CQA) including particle size (PS) less than 1000 nm, polydispersity index (PDI) less than 0.500 and Zeta potential (ZP) less than −30 mV. All surfactants produced co-crystals in the nanometer range. The PDI and PS are concentration-dependent for all nano co-crystals manufactured while only ZP was within specification when sodium dodecyl sulfate was used in the process.
- Full Text:
- Date Issued: 2020
Co-loading of isoniazid-grafted phthalocyanine-in-cyclodextrin and rifampicin in crude soybean lecithin liposomes: Formulation, spectroscopic and biological characterization
- Nkanga, Christian I, Roth, Michael, Walker, Roderick B, Noundou, Xavier S, Krause, Rui W M
- Authors: Nkanga, Christian I , Roth, Michael , Walker, Roderick B , Noundou, Xavier S , Krause, Rui W M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183481 , vital:43999 , xlink:href="https://doi.org/10.1166/jbn.2020.2880"
- Description: An inclusion complex of isoniazid-grafted phthalocyanine with gamma-cyclodextrin (Complex) was co-encapsulated with rifampicin (RIF) in crude soybean lecithin liposomes using a heating method. The encapsulation efficiency (%EE) of the Complex-RIF co-loaded liposomes (Rif-Complex-Lips) was determined using UV-Vis spectrophotometry. Rif-Complex-Lips formulations were evaluated using dynamic light scattering, transmission electron microscopy (TEM), 1H-NMR, absorption and emission spectroscopy. Dialysis was used for drug release study in two different media, pH 6.4 and 7.4. HeLa cells were used to assess potential cytotoxicity, and the uptake by lung fibroblasts and epithelial cells was investigated using fluorescence microscopy. The particle size and Zeta potential of Rif-Complex-Lips were approximately 594 nm and –50 mV. Spectroscopic analyses demonstrated molecular distribution of the cargo within the lipid core, and encapsulation efficiency of 58% for Complex and 86% for RIF. TEM analysis unveiled the existence of spherical nanoparticles in our samples, indicating the presence of liposomes. Rif-Complex-Lips exhibited much higher release rates for both INH and RIF at pH 6.4 compared to those tested at pH 7.4. In addition, there was no cytotoxicity on HeLa cells, but remarkable Rif-Complex-Lips internalization by peripheral lung fibroblasts and epithelial cells. Hence, Rif-Complex-Lips are promising vehicles for intracellular delivery of antimicrobial drugs.
- Full Text:
- Date Issued: 2020
- Authors: Nkanga, Christian I , Roth, Michael , Walker, Roderick B , Noundou, Xavier S , Krause, Rui W M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183481 , vital:43999 , xlink:href="https://doi.org/10.1166/jbn.2020.2880"
- Description: An inclusion complex of isoniazid-grafted phthalocyanine with gamma-cyclodextrin (Complex) was co-encapsulated with rifampicin (RIF) in crude soybean lecithin liposomes using a heating method. The encapsulation efficiency (%EE) of the Complex-RIF co-loaded liposomes (Rif-Complex-Lips) was determined using UV-Vis spectrophotometry. Rif-Complex-Lips formulations were evaluated using dynamic light scattering, transmission electron microscopy (TEM), 1H-NMR, absorption and emission spectroscopy. Dialysis was used for drug release study in two different media, pH 6.4 and 7.4. HeLa cells were used to assess potential cytotoxicity, and the uptake by lung fibroblasts and epithelial cells was investigated using fluorescence microscopy. The particle size and Zeta potential of Rif-Complex-Lips were approximately 594 nm and –50 mV. Spectroscopic analyses demonstrated molecular distribution of the cargo within the lipid core, and encapsulation efficiency of 58% for Complex and 86% for RIF. TEM analysis unveiled the existence of spherical nanoparticles in our samples, indicating the presence of liposomes. Rif-Complex-Lips exhibited much higher release rates for both INH and RIF at pH 6.4 compared to those tested at pH 7.4. In addition, there was no cytotoxicity on HeLa cells, but remarkable Rif-Complex-Lips internalization by peripheral lung fibroblasts and epithelial cells. Hence, Rif-Complex-Lips are promising vehicles for intracellular delivery of antimicrobial drugs.
- Full Text:
- Date Issued: 2020
Fatty acid analyses provide novel insights on hippo defecation and consequences for aquatic food webs
- Dawson, Jessica, Pillay, Deena, Perissinotto, Renzo, Richoux, Nicole B
- Authors: Dawson, Jessica , Pillay, Deena , Perissinotto, Renzo , Richoux, Nicole B
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454346 , vital:75337 , xlink:href="https://doi.org/10.1038/s41598-020-68369-5"
- Description: By defecating grasses into aquatic systems at massive scales and intensities, hippos can initiate complex changes to aquatic ecosystems. However, consequent effects on food webs are not well understood, particularly regarding shifts in basal resource contributions to consumer diets and their physiological condition. Here, we use fatty acid analysis to show that dense hippo aggregations and high dung loading are associated with (1) alterations to basal resource pools, (2) reduced quality of sediment organic matter and (3) increases in terrestrial and bacterial biomarker levels, but declines in those of diatoms in estuarine secondary consumers. While hippo defecation can increase boundary permeability between terrestrial and aquatic systems, our findings indicate that this may lead to a shift from a microphytobenthic food web base to one with increasing bacterial contributions to higher consumers. Our findings expand understanding of the mechanisms by which an iconic African megaherbivore indirectly structures aquatic ecosystems.
- Full Text:
- Date Issued: 2020
- Authors: Dawson, Jessica , Pillay, Deena , Perissinotto, Renzo , Richoux, Nicole B
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454346 , vital:75337 , xlink:href="https://doi.org/10.1038/s41598-020-68369-5"
- Description: By defecating grasses into aquatic systems at massive scales and intensities, hippos can initiate complex changes to aquatic ecosystems. However, consequent effects on food webs are not well understood, particularly regarding shifts in basal resource contributions to consumer diets and their physiological condition. Here, we use fatty acid analysis to show that dense hippo aggregations and high dung loading are associated with (1) alterations to basal resource pools, (2) reduced quality of sediment organic matter and (3) increases in terrestrial and bacterial biomarker levels, but declines in those of diatoms in estuarine secondary consumers. While hippo defecation can increase boundary permeability between terrestrial and aquatic systems, our findings indicate that this may lead to a shift from a microphytobenthic food web base to one with increasing bacterial contributions to higher consumers. Our findings expand understanding of the mechanisms by which an iconic African megaherbivore indirectly structures aquatic ecosystems.
- Full Text:
- Date Issued: 2020
Formulation optimization of smart thermosetting lamotrigine loaded hydrogels using response surface methodology, box benhken design and artificial neural networks
- Melamane, Siyabonga, Walker, Roderick B, Khamanga, Sandile M
- Authors: Melamane, Siyabonga , Walker, Roderick B , Khamanga, Sandile M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183265 , vital:43936 , xlink:href="https://doi.org/10.1080/03639045.2020.1791163"
- Description: The aim of this research was to develop lamotrigine containing thermosetting hydrogel for intranasal administration to manage and treat generalized epilepsy. Thermosetting hydrogels were prepared using different ratios of poloxamer 407 (L127), poloxamer 188 (L68) and CarbopolVR 974 P NF (C974) using the cold production process. The in situ thermosetting hydrogel was optimized using Box Behken design. Co-solvency approach was used to increase the solubility of lamotrigine by dissolving it in propylene glycol and polyethylene glycol 400 (0.2: 0.8) and the resultant solution was incorporated in the hydrogel to manufacture an LTG hydrogel. The presence of a higher amount of L127 resulted in higher viscosity at 22 0C and 34 0C and decreased the overall release of LTG. An increase in the amount of C974 resulted in a decrease in the pH of the hydrogel. The results show that formulations F10, F12, F13, F14, F15, F16 and F17 exhibited acceptable thermosetting behavior, pH and released adequate Lamotrigine above the minimum effective concentration to treat generalized epilepsy. The optimized formulation exhibited acceptable thermosetting behavior, pH and lamotrigine release but formed a stiff gel at 22 0C. The average LTG content of the optimized hydrogel was 5.00 ± 0.0225mg/ml with % recovery of 99.17%. The amount of LTG released at 12 h from the optimized hydrogel was 3.21 ± 0.0155mg and will be therapeutically effective in the brain after absorption via the olfactory region in the nasal cavity.
- Full Text:
- Date Issued: 2020
- Authors: Melamane, Siyabonga , Walker, Roderick B , Khamanga, Sandile M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183265 , vital:43936 , xlink:href="https://doi.org/10.1080/03639045.2020.1791163"
- Description: The aim of this research was to develop lamotrigine containing thermosetting hydrogel for intranasal administration to manage and treat generalized epilepsy. Thermosetting hydrogels were prepared using different ratios of poloxamer 407 (L127), poloxamer 188 (L68) and CarbopolVR 974 P NF (C974) using the cold production process. The in situ thermosetting hydrogel was optimized using Box Behken design. Co-solvency approach was used to increase the solubility of lamotrigine by dissolving it in propylene glycol and polyethylene glycol 400 (0.2: 0.8) and the resultant solution was incorporated in the hydrogel to manufacture an LTG hydrogel. The presence of a higher amount of L127 resulted in higher viscosity at 22 0C and 34 0C and decreased the overall release of LTG. An increase in the amount of C974 resulted in a decrease in the pH of the hydrogel. The results show that formulations F10, F12, F13, F14, F15, F16 and F17 exhibited acceptable thermosetting behavior, pH and released adequate Lamotrigine above the minimum effective concentration to treat generalized epilepsy. The optimized formulation exhibited acceptable thermosetting behavior, pH and lamotrigine release but formed a stiff gel at 22 0C. The average LTG content of the optimized hydrogel was 5.00 ± 0.0225mg/ml with % recovery of 99.17%. The amount of LTG released at 12 h from the optimized hydrogel was 3.21 ± 0.0155mg and will be therapeutically effective in the brain after absorption via the olfactory region in the nasal cavity.
- Full Text:
- Date Issued: 2020
Reimagining academic identities in response to research demands at Universities of Technology
- Gumbi, Thobani, McKenna, Sioux
- Authors: Gumbi, Thobani , McKenna, Sioux
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185897 , vital:44446 , xlink:href="https://doi.org/10.14426/cristal.v8i1.234"
- Description: In the last volume of this journal, Garraway and Winberg called for a reimagination of Universities of Technology (UoT) within the South African higher education system. This article continues that conversation by looking at the implications that the formation of the UoT had for academics’ identities. Technikon lecturers’ identities were closely tied to workplace expertise, but demands for research in UoTs have changed this. A social realist analysis of interviews with fifteen academics at three UoTs finds that research remains a contested issue. Interviewees understood research to take the form of acquiring postgraduate qualifications, rather than as an ongoing activity tied to their identities. Echoing Garraway and Winberg’s study, the bureaucratic nature of the institutional culture was referred to as a constraint. There was also a view that for this programme, Dental Technology, a demand for research was needed from industry if this was to be a valued aspect of academics’ identities.
- Full Text:
- Date Issued: 2020
- Authors: Gumbi, Thobani , McKenna, Sioux
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185897 , vital:44446 , xlink:href="https://doi.org/10.14426/cristal.v8i1.234"
- Description: In the last volume of this journal, Garraway and Winberg called for a reimagination of Universities of Technology (UoT) within the South African higher education system. This article continues that conversation by looking at the implications that the formation of the UoT had for academics’ identities. Technikon lecturers’ identities were closely tied to workplace expertise, but demands for research in UoTs have changed this. A social realist analysis of interviews with fifteen academics at three UoTs finds that research remains a contested issue. Interviewees understood research to take the form of acquiring postgraduate qualifications, rather than as an ongoing activity tied to their identities. Echoing Garraway and Winberg’s study, the bureaucratic nature of the institutional culture was referred to as a constraint. There was also a view that for this programme, Dental Technology, a demand for research was needed from industry if this was to be a valued aspect of academics’ identities.
- Full Text:
- Date Issued: 2020
The photodynamic antimicrobial chemotherapy of Stapphylococcus aureus using an asymmetrical zinc phthalocyanine conjugated to silver and iron oxide based nanoparticles
- Mapukata, Sivuyisiwe, Nwahara, Nnamdi, Nyokong, Tebello
- Authors: Mapukata, Sivuyisiwe , Nwahara, Nnamdi , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186078 , vital:44461 , xlink:href="https://doi.org/10.1016/j.jphotochem.2020.112813"
- Description: The synthesis and characterisation of asymmetrical zinc(II) 2(3)-mono-isophthalic acid-9(10),16(17),23 (24)-tri (tert-butylphenoxy) phthalocyanine (complex 4) are reported. The phthalocyanine is conjugated to cysteamine capped silver nanoparticles (Cys-Ag NPs), amine functionalised iron oxide magnetic nanoparticles (NH2-Fe3O4 NPs) and a core-shell composite of the two (Cys-Fe3O4@Ag) via amide bonds. The photo-physico-chemical properties of complex 4 and its respective nanoconjugates (4-Ag, 4-Fe3O4 NPs and 4-Fe3O4@Ag NPs) are also reported. The nanoconjugates showed improved triplet and singlet oxygen quantum yields compared to complex 4. The antibacterial activity of complex 4 and its nanoconjugates were also evaluated on S. aureus wherein their activity was found to be mainly visible light driven with the best catalyst being 4-Fe3O4@Ag. The work therefore demonstrates the feasibility of phthalocyanine-nanoparticle based compounds as potential agents in real life antibacterial treatment
- Full Text:
- Date Issued: 2020
- Authors: Mapukata, Sivuyisiwe , Nwahara, Nnamdi , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186078 , vital:44461 , xlink:href="https://doi.org/10.1016/j.jphotochem.2020.112813"
- Description: The synthesis and characterisation of asymmetrical zinc(II) 2(3)-mono-isophthalic acid-9(10),16(17),23 (24)-tri (tert-butylphenoxy) phthalocyanine (complex 4) are reported. The phthalocyanine is conjugated to cysteamine capped silver nanoparticles (Cys-Ag NPs), amine functionalised iron oxide magnetic nanoparticles (NH2-Fe3O4 NPs) and a core-shell composite of the two (Cys-Fe3O4@Ag) via amide bonds. The photo-physico-chemical properties of complex 4 and its respective nanoconjugates (4-Ag, 4-Fe3O4 NPs and 4-Fe3O4@Ag NPs) are also reported. The nanoconjugates showed improved triplet and singlet oxygen quantum yields compared to complex 4. The antibacterial activity of complex 4 and its nanoconjugates were also evaluated on S. aureus wherein their activity was found to be mainly visible light driven with the best catalyst being 4-Fe3O4@Ag. The work therefore demonstrates the feasibility of phthalocyanine-nanoparticle based compounds as potential agents in real life antibacterial treatment
- Full Text:
- Date Issued: 2020
Theoretical and photodynamic therapy characteristics of heteroatom doped detonation nanodiamonds linked to asymmetrical phthalocyanine for eradication of breast cancer cells
- Matshitse, Refilwe, Tshiwawa, Tendamudzimu, Managa, Muthumuni, Nwaji, Njemuwa, Lobb, Kevin A, Nyokong, Tebello
- Authors: Matshitse, Refilwe , Tshiwawa, Tendamudzimu , Managa, Muthumuni , Nwaji, Njemuwa , Lobb, Kevin A , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186089 , vital:44462 , xlink:href="https://doi.org/10.1016/j.jlumin.2020.117465"
- Description: An amide mono substituted benzothiozole phthalocyanine: zinc(II) 3-(4-((3,17,23-tris(4-(benzo [d]thiazol-2-yl)phenoxy)-9-yl)oxy) phenyl)amide phthalocyanine (NH2BzPc) was covalently linked to undoped and heteroatom doped detonation nanodiamonds (DNDs): B@DNDs, P@DNDs, S@DNDs, N@DNDs, and SandN@DNDs There is a drastic decrease in highest occupied molecular orbital (HOMO) – lowest unoccupied molecular orbital (LUMO) energy gaps for nanoconjugates compared to DNDs alone. B@DNDs-NH2BzPc, SandN@DNDs-NH2BzPc, and P@DNDs-NH2BzPc showed superior photodynamic therapy (PDT) effects. DNDs-NH2BzPc also had a small HOMO-LUMO gap, but did not show improved PDT activity compared to the Pc alone, suggesting doping of DNDs is important. This study shows improved PDT effect on Michigan Cancer Foundation-7 breast cancer lines at 7.63%, 7.62% and 6.5% cell viability for P@DNDs-NH2BzPc, SandN@DNDs-NH2BzPc and B@DNDs-NH2BzPc, respectively.
- Full Text:
- Date Issued: 2020
- Authors: Matshitse, Refilwe , Tshiwawa, Tendamudzimu , Managa, Muthumuni , Nwaji, Njemuwa , Lobb, Kevin A , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186089 , vital:44462 , xlink:href="https://doi.org/10.1016/j.jlumin.2020.117465"
- Description: An amide mono substituted benzothiozole phthalocyanine: zinc(II) 3-(4-((3,17,23-tris(4-(benzo [d]thiazol-2-yl)phenoxy)-9-yl)oxy) phenyl)amide phthalocyanine (NH2BzPc) was covalently linked to undoped and heteroatom doped detonation nanodiamonds (DNDs): B@DNDs, P@DNDs, S@DNDs, N@DNDs, and SandN@DNDs There is a drastic decrease in highest occupied molecular orbital (HOMO) – lowest unoccupied molecular orbital (LUMO) energy gaps for nanoconjugates compared to DNDs alone. B@DNDs-NH2BzPc, SandN@DNDs-NH2BzPc, and P@DNDs-NH2BzPc showed superior photodynamic therapy (PDT) effects. DNDs-NH2BzPc also had a small HOMO-LUMO gap, but did not show improved PDT activity compared to the Pc alone, suggesting doping of DNDs is important. This study shows improved PDT effect on Michigan Cancer Foundation-7 breast cancer lines at 7.63%, 7.62% and 6.5% cell viability for P@DNDs-NH2BzPc, SandN@DNDs-NH2BzPc and B@DNDs-NH2BzPc, respectively.
- Full Text:
- Date Issued: 2020
Understanding the context of multifaceted collaborations for social-ecological sustainability: A methodology for cross-case analysis
- Cockburn, Jessica J, Schoon, Michael, Cundill, Georgina, Robinson, Cathy, Aburto, Jamie A, Alexander, Steve M, Baggio, Jacopo A, Barnaud, Cecile, Chapman, Mollie, Llorente, Marina G, Garcia-Lopez, Gustavo A, Hill, Rosemary, Speranza, Chinwe I, Lee, Jean, Meek, Chanda L, Rosenberg, Eureta, Schultz, Lisen, Thondhlana, Gladman
- Authors: Cockburn, Jessica J , Schoon, Michael , Cundill, Georgina , Robinson, Cathy , Aburto, Jamie A , Alexander, Steve M , Baggio, Jacopo A , Barnaud, Cecile , Chapman, Mollie , Llorente, Marina G , Garcia-Lopez, Gustavo A , Hill, Rosemary , Speranza, Chinwe I , Lee, Jean , Meek, Chanda L , Rosenberg, Eureta , Schultz, Lisen , Thondhlana, Gladman
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370725 , vital:66371 , xlink:href="https://doi.org/10.5751/ES-11527-250307"
- Description: There are limited approaches available that enable researchers and practitioners to conduct multiple case study comparisons of complex cases of collaboration in natural resource management and conservation. The absence of such tools is felt despite the fact that over the past several years a great deal of literature has reviewed the state of the science regarding collaboration. Much of this work is based on case studies of collaboration and highlights the importance of contextual variables, further complicating efforts to compare outcomes across case-study areas and the likely failure of approaches based on one size fits all generalizations. We expand on the standard overview of the field by identifying some of the challenges associated with managing complex systems with multiple resources, multiple stakeholder groups with diverse knowledges/understandings, and multiple objectives across multiple scales, i.e., multifaceted collaborative initiatives. We then elucidate how a realist methodology, within a critical realist framing, can support efforts to compare multiple case studies of such multifaceted initiatives. The methodology we propose considers the importance and impact of context for the origins, purpose, and success of multifaceted collaborative natural resource management and conservation initiatives in social-ecological systems.
- Full Text:
- Date Issued: 2020
- Authors: Cockburn, Jessica J , Schoon, Michael , Cundill, Georgina , Robinson, Cathy , Aburto, Jamie A , Alexander, Steve M , Baggio, Jacopo A , Barnaud, Cecile , Chapman, Mollie , Llorente, Marina G , Garcia-Lopez, Gustavo A , Hill, Rosemary , Speranza, Chinwe I , Lee, Jean , Meek, Chanda L , Rosenberg, Eureta , Schultz, Lisen , Thondhlana, Gladman
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370725 , vital:66371 , xlink:href="https://doi.org/10.5751/ES-11527-250307"
- Description: There are limited approaches available that enable researchers and practitioners to conduct multiple case study comparisons of complex cases of collaboration in natural resource management and conservation. The absence of such tools is felt despite the fact that over the past several years a great deal of literature has reviewed the state of the science regarding collaboration. Much of this work is based on case studies of collaboration and highlights the importance of contextual variables, further complicating efforts to compare outcomes across case-study areas and the likely failure of approaches based on one size fits all generalizations. We expand on the standard overview of the field by identifying some of the challenges associated with managing complex systems with multiple resources, multiple stakeholder groups with diverse knowledges/understandings, and multiple objectives across multiple scales, i.e., multifaceted collaborative initiatives. We then elucidate how a realist methodology, within a critical realist framing, can support efforts to compare multiple case studies of such multifaceted initiatives. The methodology we propose considers the importance and impact of context for the origins, purpose, and success of multifaceted collaborative natural resource management and conservation initiatives in social-ecological systems.
- Full Text:
- Date Issued: 2020
Characterization of electrodes modified with nanocomposites of cobalt tetraaminophenoxyphthalocyanine, reduced graphene and multi-walled carbon nanotubes
- Shumba, Munyaradz, Nyoni, Stephen, Britton, Jonathan, Nyokong, Tebello
- Authors: Shumba, Munyaradz , Nyoni, Stephen , Britton, Jonathan , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187003 , vital:44555 , xlink:href="https://doi.org/10.1080/00958972.2019.1621299"
- Description: Glassy carbon electrodes or plates were modified with nanocomposites consisting of cobalt tetraaminophenoxyphthalocyanine (CoTAPhPc), reduced graphene oxide nanosheets (rGONs) and multi-walled carbon nanotubes (MWCNTs). The modified electrodes were characterized using cyclic voltammetry, scanning electrochemical microscopy (SECM) and time-of-flight-secondary ion mass spectrometer (TOF-SIMS). The electrocatalytic activity of the modified electrode was tested for detection of L-cysteine. The presence of CoTAPhPc on sequential layers of MWCNT and rGONs resulted in improved detection currents compared to CoTAPhPc alone or when MWCNT/rGONs are mixed in CoTAPhPc–MWCNT/ rGONs (mix)–glassy carbon electrode (GCE). CoTAPhPc–MWCNT–GCE (without rGONS) showed higher sensitivity toward L-cysteine as compared to the probes incorporating rGONs with a catalytic rate constant of 4.62x104 M-1 s-1 and a detection limit of 30 nM. The presence of rGONs improved the stability of the electrode.
- Full Text:
- Date Issued: 2019
- Authors: Shumba, Munyaradz , Nyoni, Stephen , Britton, Jonathan , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187003 , vital:44555 , xlink:href="https://doi.org/10.1080/00958972.2019.1621299"
- Description: Glassy carbon electrodes or plates were modified with nanocomposites consisting of cobalt tetraaminophenoxyphthalocyanine (CoTAPhPc), reduced graphene oxide nanosheets (rGONs) and multi-walled carbon nanotubes (MWCNTs). The modified electrodes were characterized using cyclic voltammetry, scanning electrochemical microscopy (SECM) and time-of-flight-secondary ion mass spectrometer (TOF-SIMS). The electrocatalytic activity of the modified electrode was tested for detection of L-cysteine. The presence of CoTAPhPc on sequential layers of MWCNT and rGONs resulted in improved detection currents compared to CoTAPhPc alone or when MWCNT/rGONs are mixed in CoTAPhPc–MWCNT/ rGONs (mix)–glassy carbon electrode (GCE). CoTAPhPc–MWCNT–GCE (without rGONS) showed higher sensitivity toward L-cysteine as compared to the probes incorporating rGONs with a catalytic rate constant of 4.62x104 M-1 s-1 and a detection limit of 30 nM. The presence of rGONs improved the stability of the electrode.
- Full Text:
- Date Issued: 2019
Feminine sexual desire and shame in the classroom: an educator’s constructions of and investments in sexuality education
- Saville Young, Lisa, Moodley, Dale D, Macleod, Catriona I
- Authors: Saville Young, Lisa , Moodley, Dale D , Macleod, Catriona I
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444302 , vital:74215 , xlink:href="https://doi.org/10.1080/14681811.2018.1511974"
- Description: Within the growing body of literature on sexuality education in South Africa, researchers have highlighted how teachers may face, or themselves be, barriers to the implementation of rights-based comprehensive sexuality education. Important issues with regard to educators are: firstly, the social and discursive space within which educators are located; and secondly, the complex emotional and psychic investments that educators take up within particular discourses and practices. This paper explores, through a psychosocial reading of an interview extract with a particular educator based in the Eastern Cape of South Africa, how discursive and psychic concerns are sutured within the complex subjectivity of the educator as the medium for sexual education in schools. Specifically, it highlights the numerous ways in which feminine sexuality and desire may be avoided, denied and silenced. Even when feminine desire is specifically evoked as in this case, it is done so in a way that ensures social and cultural respectability, thereby reproducing shame narratives that form and maintain traditional gender discourses. Our analysis demonstrates how engaging with educators as subjects with their own sexual history and psychic dynamics, and as individuals with raced, gendered and classed identities, is a potentially transformative perspective for effective sexuality education.
- Full Text:
- Date Issued: 2019
- Authors: Saville Young, Lisa , Moodley, Dale D , Macleod, Catriona I
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444302 , vital:74215 , xlink:href="https://doi.org/10.1080/14681811.2018.1511974"
- Description: Within the growing body of literature on sexuality education in South Africa, researchers have highlighted how teachers may face, or themselves be, barriers to the implementation of rights-based comprehensive sexuality education. Important issues with regard to educators are: firstly, the social and discursive space within which educators are located; and secondly, the complex emotional and psychic investments that educators take up within particular discourses and practices. This paper explores, through a psychosocial reading of an interview extract with a particular educator based in the Eastern Cape of South Africa, how discursive and psychic concerns are sutured within the complex subjectivity of the educator as the medium for sexual education in schools. Specifically, it highlights the numerous ways in which feminine sexuality and desire may be avoided, denied and silenced. Even when feminine desire is specifically evoked as in this case, it is done so in a way that ensures social and cultural respectability, thereby reproducing shame narratives that form and maintain traditional gender discourses. Our analysis demonstrates how engaging with educators as subjects with their own sexual history and psychic dynamics, and as individuals with raced, gendered and classed identities, is a potentially transformative perspective for effective sexuality education.
- Full Text:
- Date Issued: 2019
Photophysical and nonlinear optical characteristics of pyridyl substituted phthalocyanine-detonation nanodiamond conjugated systems in solution
- Matshitse, Refilwe, Khene, Samson M, Nyokong, Tebello
- Authors: Matshitse, Refilwe , Khene, Samson M , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187079 , vital:44563 , xlink:href="https://doi.org/10.1016/j.diamond.2019.03.013"
- Description: In this study photophysical, nonlinear absorption and optical limiting properties of detonation nanodiamonds (DNDs)-phthalocyanine nanoconjugate systems containing: 2,9(10),16(17),23(24)-tetrakis-(4-pyridyloxy) phthalocyaninato (H2TPPc), 2,9(10),16(17),23(24)-tetrakis-(4-pyridyloxy) phthalocyanato zinc(II) (ZnTPPc) and 2,9(10),16(17),23(24)-tetrakis-(4-pyridyloxy) phthalocyanato silicon(IV) hydroxide (Si(OH)2TPPc), were investigated in dimethylsulfoxide solution. Pcs were non-covalently linked to nanondiamonds (also covalently linked for Si(OH)2TPPc) and investigated using 532 nm laser excitation at 10 ns pulses for their optical limiting properties. Complexes that have higher triplet state absorption also possessed enhanced nonlinear optical behaviour following reverse saturable absorption mechanism. Superior optical performance is observed when the Pcs had a central metal with axial ligands conjugated to DNDs in solution. Nanoconjugate of DNDs-Si(OH)2TPPc and respective Pc in solution gave the highest imaginary third-order susceptibility (Im[X(3)]) and hyperpolarizability (γ) at 2.91 × 10−8 and 3.17 × 10−8 esu and 3.88 × 10−28 and 4.22 × 10−28 esu, respectively, with Ilim value of 0.47 and 0.39 J·cm−2.
- Full Text:
- Date Issued: 2019
- Authors: Matshitse, Refilwe , Khene, Samson M , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187079 , vital:44563 , xlink:href="https://doi.org/10.1016/j.diamond.2019.03.013"
- Description: In this study photophysical, nonlinear absorption and optical limiting properties of detonation nanodiamonds (DNDs)-phthalocyanine nanoconjugate systems containing: 2,9(10),16(17),23(24)-tetrakis-(4-pyridyloxy) phthalocyaninato (H2TPPc), 2,9(10),16(17),23(24)-tetrakis-(4-pyridyloxy) phthalocyanato zinc(II) (ZnTPPc) and 2,9(10),16(17),23(24)-tetrakis-(4-pyridyloxy) phthalocyanato silicon(IV) hydroxide (Si(OH)2TPPc), were investigated in dimethylsulfoxide solution. Pcs were non-covalently linked to nanondiamonds (also covalently linked for Si(OH)2TPPc) and investigated using 532 nm laser excitation at 10 ns pulses for their optical limiting properties. Complexes that have higher triplet state absorption also possessed enhanced nonlinear optical behaviour following reverse saturable absorption mechanism. Superior optical performance is observed when the Pcs had a central metal with axial ligands conjugated to DNDs in solution. Nanoconjugate of DNDs-Si(OH)2TPPc and respective Pc in solution gave the highest imaginary third-order susceptibility (Im[X(3)]) and hyperpolarizability (γ) at 2.91 × 10−8 and 3.17 × 10−8 esu and 3.88 × 10−28 and 4.22 × 10−28 esu, respectively, with Ilim value of 0.47 and 0.39 J·cm−2.
- Full Text:
- Date Issued: 2019
The obstinate notion that higher education is a meritocracy
- Sobuwa, Simpiwe, McKenna, Sioux
- Authors: Sobuwa, Simpiwe , McKenna, Sioux
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187150 , vital:44574 , xlink:href="https://doi.org/10.14426/cristal.v7i2.184"
- Description: Student success is an enormous concern in light of the high drop-out rates in South African universities. There is a wealth of local and international research which provides complex explanations for these statistics, but the common-sense understanding is that those students who have the right attributes and who work hard will do well. While the notion of higher education as a meritocracy is pervasive, it is invalid given the effects of numerous other mechanisms at play in the students' educational experiences. This article draws from the literature to discuss the problems of the meritocratic explanation in how it fails to sufficiently account for the centrality of agency and the ways in which this intersects with societal structures. We argue that more useful understandings of student success and failure require social theory that acknowledges the complexities underpinning student success or failure.
- Full Text:
- Date Issued: 2019
- Authors: Sobuwa, Simpiwe , McKenna, Sioux
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187150 , vital:44574 , xlink:href="https://doi.org/10.14426/cristal.v7i2.184"
- Description: Student success is an enormous concern in light of the high drop-out rates in South African universities. There is a wealth of local and international research which provides complex explanations for these statistics, but the common-sense understanding is that those students who have the right attributes and who work hard will do well. While the notion of higher education as a meritocracy is pervasive, it is invalid given the effects of numerous other mechanisms at play in the students' educational experiences. This article draws from the literature to discuss the problems of the meritocratic explanation in how it fails to sufficiently account for the centrality of agency and the ways in which this intersects with societal structures. We argue that more useful understandings of student success and failure require social theory that acknowledges the complexities underpinning student success or failure.
- Full Text:
- Date Issued: 2019
Electrocatalytic activity of a push-pull phthalocyanine in the presence of reduced and amino functionalized graphene quantum dots towards the electrooxidation of hydrazine
- Centane, Sixolile, Sekhosana, Kutloana E, Matshitse, Refilwe, Nyokong, Tebello
- Authors: Centane, Sixolile , Sekhosana, Kutloana E , Matshitse, Refilwe , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233456 , vital:50092 , xlink:href="https://doi.org/10.1016/j.jelechem.2018.05.005"
- Description: We report on the electrochemical behaviour of reduced graphene quantum dots (rGQDs) compared to amino functionalized graphene quantum dots (NH2GQDs). Reduction of the GQDs entails the elimination of the excessive carboxyl and hydrogen groups on the GQDs surface, thereby reducing the energy band gap. The energy band gap of graphene is directly proportional to the available oxygen atoms. The two GQD types were conjugated to a novel cobalt phthalocyanine (cobalt tris-(tert-butyl phenoxy)-mono-carboxyphenoxy phthalocyanine, CoPc) via covalent and nom-covalent interactions. The resulting conjugates were tested towards the electrooxidation of hydrazine. The conjugates are represented as rGQDs(π)CoPc, NH2(π)CoPc, rGQDs@CoPc and NH2GQDs@CoPc. The resulting conjugates were adsorbed onto a glassy carbon electrode using the drop and dry method. The lowest limit of detection (LOD) was obtained for rGQDs(π)CoPc.
- Full Text:
- Date Issued: 2018
- Authors: Centane, Sixolile , Sekhosana, Kutloana E , Matshitse, Refilwe , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233456 , vital:50092 , xlink:href="https://doi.org/10.1016/j.jelechem.2018.05.005"
- Description: We report on the electrochemical behaviour of reduced graphene quantum dots (rGQDs) compared to amino functionalized graphene quantum dots (NH2GQDs). Reduction of the GQDs entails the elimination of the excessive carboxyl and hydrogen groups on the GQDs surface, thereby reducing the energy band gap. The energy band gap of graphene is directly proportional to the available oxygen atoms. The two GQD types were conjugated to a novel cobalt phthalocyanine (cobalt tris-(tert-butyl phenoxy)-mono-carboxyphenoxy phthalocyanine, CoPc) via covalent and nom-covalent interactions. The resulting conjugates were tested towards the electrooxidation of hydrazine. The conjugates are represented as rGQDs(π)CoPc, NH2(π)CoPc, rGQDs@CoPc and NH2GQDs@CoPc. The resulting conjugates were adsorbed onto a glassy carbon electrode using the drop and dry method. The lowest limit of detection (LOD) was obtained for rGQDs(π)CoPc.
- Full Text:
- Date Issued: 2018
Nontimber forest products as ecological and biocultural keystone species
- Shackleton, Charlie M, Ticktin, Tamara, Cunningham, Anthony B
- Authors: Shackleton, Charlie M , Ticktin, Tamara , Cunningham, Anthony B
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180388 , vital:43359 , xlink:href="https://doi.org/10.5751/ES-10469-230422"
- Description: Nontimber forests products (NTFPs) are the mainstay of rural livelihoods and local economies the world over. As such they are of interest to a wide disciplinary range of researchers and development and government agencies seeking to promote livelihoods, incomes, and ecologically sustainable practices. With the attention on the various human uses of NTFPs, their role and networks in the broader biological communities in which they are located are frequently overlooked. Harvesting of many NTFPs has effects not only at the organism and population scales, but also on co-occurring species, some of which may also be NTFPs. Thus, reduction or loss of one NTFP population or species in a specific area may have cascade effects on other NTFP species, including those used for cultural purposes. We illustrate the little appreciated importance of NTFPs in broader ecological and social systems by assessing and illustrating the importance of NTFP species as ecological or biocultural keystones in providing regulating and supporting ecological services to other species and cultural services to people. We present a number of examples where NTFP species act as keystones in ecological and cultural systems, including food, pollination and dispersal, animal health, nutrients, shelter and protection, and cultural symbolism, most of which have not been considered by NTFP researchers and practitioners. From these examples we distill six propositions regarding NTFPs and discuss the value of recognizing some NTFPs as biocultural keystones to acknowledge and highlight their roles at broader scales.
- Full Text:
- Date Issued: 2018
- Authors: Shackleton, Charlie M , Ticktin, Tamara , Cunningham, Anthony B
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180388 , vital:43359 , xlink:href="https://doi.org/10.5751/ES-10469-230422"
- Description: Nontimber forests products (NTFPs) are the mainstay of rural livelihoods and local economies the world over. As such they are of interest to a wide disciplinary range of researchers and development and government agencies seeking to promote livelihoods, incomes, and ecologically sustainable practices. With the attention on the various human uses of NTFPs, their role and networks in the broader biological communities in which they are located are frequently overlooked. Harvesting of many NTFPs has effects not only at the organism and population scales, but also on co-occurring species, some of which may also be NTFPs. Thus, reduction or loss of one NTFP population or species in a specific area may have cascade effects on other NTFP species, including those used for cultural purposes. We illustrate the little appreciated importance of NTFPs in broader ecological and social systems by assessing and illustrating the importance of NTFP species as ecological or biocultural keystones in providing regulating and supporting ecological services to other species and cultural services to people. We present a number of examples where NTFP species act as keystones in ecological and cultural systems, including food, pollination and dispersal, animal health, nutrients, shelter and protection, and cultural symbolism, most of which have not been considered by NTFP researchers and practitioners. From these examples we distill six propositions regarding NTFPs and discuss the value of recognizing some NTFPs as biocultural keystones to acknowledge and highlight their roles at broader scales.
- Full Text:
- Date Issued: 2018
The green economy learning assessment South Africa: Lessons for higher education, skills and work-based learning
- Rosenberg, Eureta, Lotz-Sisitka, Heila, Ramsarup, Presha
- Authors: Rosenberg, Eureta , Lotz-Sisitka, Heila , Ramsarup, Presha
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182765 , vital:43872 , xlink:href="https://doi.org/10.1108/HESWBL-03-2018-0041"
- Description: The purpose of this paper is to share and analyse the methodology and findings of the 2016 Green Economy Learning Assessment South Africa, including learning needs identified with reference to the competency framings of Scharmer (2009) and Wiek et al. (2011); and implications for university and work-based sustainability education, broadly conceptualised in a just transitions framework. The assessment was conducted using desktop policy reviews and an audit of sustainability education providers, online questionnaires to sector experts, focus groups and interviews with practitioners driving green economy initiatives. Policy monitoring and evaluation, and education for sustainable development, emerged as key change levers across nine priority areas including agriculture, energy, natural resources, water, transport and infrastructure. The competencies required to drive sustainability in these areas were clustered as technical, relational and transformational competencies for: making the case; integrated sustainable development planning; strategic adaptive management and expansive learning; working across organisational units; working across knowledge fields; capacity and organisational development; and principle-based leadership. Practitioners develop such competencies through formal higher education and short courses plus course-activated networks and “on the job” learning. The paper adds to the literature on sustainability competencies and raises questions regarding forms of hybrid learning suitable for developing technical, relational and transformative competencies. A national learning needs assessment methodology and tools for customised organisational learning needs assessments are shared. The assessment methodology is novel in this context and the workplace-based tools, original.
- Full Text:
- Date Issued: 2018
- Authors: Rosenberg, Eureta , Lotz-Sisitka, Heila , Ramsarup, Presha
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182765 , vital:43872 , xlink:href="https://doi.org/10.1108/HESWBL-03-2018-0041"
- Description: The purpose of this paper is to share and analyse the methodology and findings of the 2016 Green Economy Learning Assessment South Africa, including learning needs identified with reference to the competency framings of Scharmer (2009) and Wiek et al. (2011); and implications for university and work-based sustainability education, broadly conceptualised in a just transitions framework. The assessment was conducted using desktop policy reviews and an audit of sustainability education providers, online questionnaires to sector experts, focus groups and interviews with practitioners driving green economy initiatives. Policy monitoring and evaluation, and education for sustainable development, emerged as key change levers across nine priority areas including agriculture, energy, natural resources, water, transport and infrastructure. The competencies required to drive sustainability in these areas were clustered as technical, relational and transformational competencies for: making the case; integrated sustainable development planning; strategic adaptive management and expansive learning; working across organisational units; working across knowledge fields; capacity and organisational development; and principle-based leadership. Practitioners develop such competencies through formal higher education and short courses plus course-activated networks and “on the job” learning. The paper adds to the literature on sustainability competencies and raises questions regarding forms of hybrid learning suitable for developing technical, relational and transformative competencies. A national learning needs assessment methodology and tools for customised organisational learning needs assessments are shared. The assessment methodology is novel in this context and the workplace-based tools, original.
- Full Text:
- Date Issued: 2018
The investigation of in vitro dark cytotoxicity and photodynamic therapy effect of a 2, 6-dibromo-3, 5-distyryl BODIPY dye encapsulated in Pluronic® F-127 micelles
- Molupe, Nthabeleng, Babu, Balaji, Oluwole, David O, Prinsloo, Earl, Mack, John, Nyokong, Tebello
- Authors: Molupe, Nthabeleng , Babu, Balaji , Oluwole, David O , Prinsloo, Earl , Mack, John , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187862 , vital:44704 , xlink:href="https://doi.org/10.1080/00958972.2018.1522536"
- Description: A 2,6-dibrominated 3,5-distyryl boron-dipyrromethene (BODIPY) dye with a moderately high singlet oxygen quantum yield was encapsulated in Pluronic® F-127 micelles, and its dark cytotoxicity and photodynamic activity were investigated on the human breast adenocarcinoma MCF-7 cell line. The BODIPY dye exhibited very low dark toxicity and a significant PDT effect when added in drug formulations consisting of 5.0% (v/v) DMSO in supplemented Dulbecco’s modified Eagle’s medium (DMEM) and as Pluronic® F-127 micelle encapsulation complexes in supplemented DMEM alone. An IC50 value of 4 ± 2 μM was obtained when the BODIPY dye was encapsulated in Pluronic® F-127 micelles during in vitro photodynamic activity studies in MCF-7 cancer cells with a 660 nm light emitting diode.
- Full Text:
- Date Issued: 2018
- Authors: Molupe, Nthabeleng , Babu, Balaji , Oluwole, David O , Prinsloo, Earl , Mack, John , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187862 , vital:44704 , xlink:href="https://doi.org/10.1080/00958972.2018.1522536"
- Description: A 2,6-dibrominated 3,5-distyryl boron-dipyrromethene (BODIPY) dye with a moderately high singlet oxygen quantum yield was encapsulated in Pluronic® F-127 micelles, and its dark cytotoxicity and photodynamic activity were investigated on the human breast adenocarcinoma MCF-7 cell line. The BODIPY dye exhibited very low dark toxicity and a significant PDT effect when added in drug formulations consisting of 5.0% (v/v) DMSO in supplemented Dulbecco’s modified Eagle’s medium (DMEM) and as Pluronic® F-127 micelle encapsulation complexes in supplemented DMEM alone. An IC50 value of 4 ± 2 μM was obtained when the BODIPY dye was encapsulated in Pluronic® F-127 micelles during in vitro photodynamic activity studies in MCF-7 cancer cells with a 660 nm light emitting diode.
- Full Text:
- Date Issued: 2018
Writing groups as transformative spaces
- Wilmot, Kirstin, McKenna, Sioux
- Authors: Wilmot, Kirstin , McKenna, Sioux
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:44576 , xlink:href="https://doi.org/10.1080/07294360.2018.1450361"
- Description: Curriculum transformation is a central concern for higher education in response to rapidly expanding technologies, globalisation and the widening diversity of the student and staff body. This is particularly true for South Africa, which is still grappling with inequalities and pressure for social redress in its universities. Early responses to supporting students took the form of add-on, ‘deficit-model’ approaches which understood poor student retention and success rates as emerging from students’ lack of neutral literacy ‘skills’. Recent initiatives have begun to adopt more socio-cultural understandings of literacy that seek to challenge traditional power structures and cultivate horizontal peer-orientated spaces for learning with a focus on practice rather than on product. Writing groups, as spaces for academic writing development, embrace this orientation and are argued to provide a transformative framework that foregrounds proactive student learning and experience, while still accommodating disciplinary learning through peer engagement. Drawing on the successful implementation of such forms of support at a research-intensive university, this paper argues that writing groups can play a critical role in both personal (student) transformation and broader curriculum transformation. Data include anonymous questionnaires and surveys with participants and coordinators of the writing groups. An inductive, constant comparative analysis indicated that students feel empowered in this space to develop not only their writing practices but also their transforming identities as scholars. Writing groups were found to provide ‘safe spaces’ where academic practices can be made explicit and where they can be challenged. The paper therefore argues that writing groups can play a small but key role in broader transformation efforts.
- Full Text:
- Date Issued: 2018
- Authors: Wilmot, Kirstin , McKenna, Sioux
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:44576 , xlink:href="https://doi.org/10.1080/07294360.2018.1450361"
- Description: Curriculum transformation is a central concern for higher education in response to rapidly expanding technologies, globalisation and the widening diversity of the student and staff body. This is particularly true for South Africa, which is still grappling with inequalities and pressure for social redress in its universities. Early responses to supporting students took the form of add-on, ‘deficit-model’ approaches which understood poor student retention and success rates as emerging from students’ lack of neutral literacy ‘skills’. Recent initiatives have begun to adopt more socio-cultural understandings of literacy that seek to challenge traditional power structures and cultivate horizontal peer-orientated spaces for learning with a focus on practice rather than on product. Writing groups, as spaces for academic writing development, embrace this orientation and are argued to provide a transformative framework that foregrounds proactive student learning and experience, while still accommodating disciplinary learning through peer engagement. Drawing on the successful implementation of such forms of support at a research-intensive university, this paper argues that writing groups can play a critical role in both personal (student) transformation and broader curriculum transformation. Data include anonymous questionnaires and surveys with participants and coordinators of the writing groups. An inductive, constant comparative analysis indicated that students feel empowered in this space to develop not only their writing practices but also their transforming identities as scholars. Writing groups were found to provide ‘safe spaces’ where academic practices can be made explicit and where they can be challenged. The paper therefore argues that writing groups can play a small but key role in broader transformation efforts.
- Full Text:
- Date Issued: 2018