Engagement in local social-ecological knowledge practices in a seasonal cycles approach for transitioning to future sustainability
- Authors: O'Donoghue, Rob B
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/387971 , vital:68294 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/186419"
- Description: This paper explores climate as variable natural forces driving seasonal cycles1 that many African cultures had adjusted themselves to within intergenerational knowledge practices of longue durée. The study points to the need to re-orientate and expand climate science education so that it is centred on the seasonal cycles and intergenerational learning to better align transitioning to future sustainability with these in our southern African contexts of climate change today. The narrative touches upon historical accounts of knowledge practices amongst the Krobo, Bemba, Shona, Zulu and Xhosa, briefly pointing to how each, as an African culture, is situated as a social-ecological entity within the climatic tapestries of our African landscapes. It takes note of how cultural articulation within the seasonal cycles of regional climate have a long history with adaptive change in some contexts in more recent times. The review suggests that our learning in relation to emerging climate change should be informed by these histories of intergenerational knowledge practice. It notes how a better grasp of these could be important drivers of a widening cultural response to the changing dynamics in our climatic surroundings today. The brief study suggests that southern Africa is a special place with many unique and interesting climatic processes and associated socio-ecological systems and practices. These can provide engaging perspectives for informing education to mitigate or adapt to climate change. Here, a situated exploration of seasonal cycles can draw on both the latest in modern climate science and the rich social-ecological heritage of Africa briefly touched upon in the study. A model of process is offered for how both can be used in a seasonal cycles approach climate change education. This better situated and more inclusive approach can enable us to contemplate how we might best adjust our social-ecological dispositions and practices in the changing world that we all share.
- Full Text:
- Date Issued: 2019
- Authors: O'Donoghue, Rob B
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/387971 , vital:68294 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/186419"
- Description: This paper explores climate as variable natural forces driving seasonal cycles1 that many African cultures had adjusted themselves to within intergenerational knowledge practices of longue durée. The study points to the need to re-orientate and expand climate science education so that it is centred on the seasonal cycles and intergenerational learning to better align transitioning to future sustainability with these in our southern African contexts of climate change today. The narrative touches upon historical accounts of knowledge practices amongst the Krobo, Bemba, Shona, Zulu and Xhosa, briefly pointing to how each, as an African culture, is situated as a social-ecological entity within the climatic tapestries of our African landscapes. It takes note of how cultural articulation within the seasonal cycles of regional climate have a long history with adaptive change in some contexts in more recent times. The review suggests that our learning in relation to emerging climate change should be informed by these histories of intergenerational knowledge practice. It notes how a better grasp of these could be important drivers of a widening cultural response to the changing dynamics in our climatic surroundings today. The brief study suggests that southern Africa is a special place with many unique and interesting climatic processes and associated socio-ecological systems and practices. These can provide engaging perspectives for informing education to mitigate or adapt to climate change. Here, a situated exploration of seasonal cycles can draw on both the latest in modern climate science and the rich social-ecological heritage of Africa briefly touched upon in the study. A model of process is offered for how both can be used in a seasonal cycles approach climate change education. This better situated and more inclusive approach can enable us to contemplate how we might best adjust our social-ecological dispositions and practices in the changing world that we all share.
- Full Text:
- Date Issued: 2019
Evaluation of the photosensitizing properties of zinc and indium tetra cinnamic acid phthalocyanines linked to magnetic nanoparticles on human breast adenocarcinoma cells
- Matlou, Gauta G, Oluwole, David O, Nyokong, Tebello
- Authors: Matlou, Gauta G , Oluwole, David O , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187582 , vital:44673 , xlink:href="https://doi.org/10.1016/j.jlumin.2018.09.054"
- Description: This work reports on the synthesis, photophysico-chemical properties and photodynamic therapy activity of novel zinc (1) and indium (2) tetra substituted cinnamic acid phthalocyanine (Pc) complexes linked to amino functionalized magnetic nanoparticles (AMNPs) through an amide bond. Asymmetric ZnPc complex (3) showed better triplet and singlet oxygen quantum yields as compared to its symmetrical analogues (1 and 2). The AMNPs (1-AMNPs and 2-AMNPs) linked conjugates depicted increased triplet quantum yields in comparison to their unlinked Pcs, while 3-AMNPs showed a decrease compared to 3. The complexes showed increased in-vitro photo-cytotoxic effect against MCF-7 cells with an increase in drug concentration. At 80 µg/mL, 2 and 3, 2-AMNPs and 3-AMNPs with higher singlet oxygen quantum yields caused more cytotoxic effect on the cancer cells in the presence of light as compared to 1 and 1-AMNPs respectively.
- Full Text:
- Date Issued: 2019
- Authors: Matlou, Gauta G , Oluwole, David O , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187582 , vital:44673 , xlink:href="https://doi.org/10.1016/j.jlumin.2018.09.054"
- Description: This work reports on the synthesis, photophysico-chemical properties and photodynamic therapy activity of novel zinc (1) and indium (2) tetra substituted cinnamic acid phthalocyanine (Pc) complexes linked to amino functionalized magnetic nanoparticles (AMNPs) through an amide bond. Asymmetric ZnPc complex (3) showed better triplet and singlet oxygen quantum yields as compared to its symmetrical analogues (1 and 2). The AMNPs (1-AMNPs and 2-AMNPs) linked conjugates depicted increased triplet quantum yields in comparison to their unlinked Pcs, while 3-AMNPs showed a decrease compared to 3. The complexes showed increased in-vitro photo-cytotoxic effect against MCF-7 cells with an increase in drug concentration. At 80 µg/mL, 2 and 3, 2-AMNPs and 3-AMNPs with higher singlet oxygen quantum yields caused more cytotoxic effect on the cancer cells in the presence of light as compared to 1 and 1-AMNPs respectively.
- Full Text:
- Date Issued: 2019
Excavating the South African teacher leadership archive
- Authors: Grant, Carolyn
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281051 , vital:55687 , xlink:href="https://doi.org/10.1177/1741143217717274"
- Description: In established democracies, the notion of ‘singular’ school leadership practised by the principal has been challenged and a more expansive approach to leadership which includes the practice of teacher leadership is now widely accepted by practitioners and researchers alike. In contrast, in emerging democracies the practice of teacher leadership is less obvious, despite the embeddedness of the concept in policy discourse. This article takes South Africa as its case and reviews literature on teacher leadership in this emerging African democracy. It draws on published articles and unpublished postgraduate theses with a specific teacher leadership focus and loosely adopts the format of two previously published comprehensive literature reviews in organising its findings. Similar to the findings of these two literature reviews, this South African archive also shows that the majority of research in this domain is conspicuously descriptive rather than explanatory, largely atheoretical and overly reliant on small case study design. In response, this article argues that teacher leadership research must continue to be undertaken in emerging democracies but with far greater use made of critical methodologies underpinned by relevant social theory.
- Full Text:
- Date Issued: 2019
- Authors: Grant, Carolyn
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281051 , vital:55687 , xlink:href="https://doi.org/10.1177/1741143217717274"
- Description: In established democracies, the notion of ‘singular’ school leadership practised by the principal has been challenged and a more expansive approach to leadership which includes the practice of teacher leadership is now widely accepted by practitioners and researchers alike. In contrast, in emerging democracies the practice of teacher leadership is less obvious, despite the embeddedness of the concept in policy discourse. This article takes South Africa as its case and reviews literature on teacher leadership in this emerging African democracy. It draws on published articles and unpublished postgraduate theses with a specific teacher leadership focus and loosely adopts the format of two previously published comprehensive literature reviews in organising its findings. Similar to the findings of these two literature reviews, this South African archive also shows that the majority of research in this domain is conspicuously descriptive rather than explanatory, largely atheoretical and overly reliant on small case study design. In response, this article argues that teacher leadership research must continue to be undertaken in emerging democracies but with far greater use made of critical methodologies underpinned by relevant social theory.
- Full Text:
- Date Issued: 2019
Expansive Social Learning, Morphogenesis and Reflexive Action in an Organization Responding to Wetland Degradation
- Lindley, David S, Lotz-Sisitka, Heila
- Authors: Lindley, David S , Lotz-Sisitka, Heila
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182450 , vital:43831 , xlink:href="https://doi.org/10.3390/su11154230"
- Description: This study (conducted as PhD research at Rhodes University, South Africa) describes a formative interventionist research project conducted to explore factors inhibiting improved wetland management within a corporate plantation forestry context and determine if, and how, expansive social learning processes could strengthen organizational learning and development to overcome these factors. A series of formative interventionist workshops and feedback meetings took place over three years; developing new knowledge amongst staff of Company X, and improved wetland management practices. Through the expansive learning process, the tensions and contradictions that emerged became generative, supporting expansive learning that was reflectively engaged with throughout the research period. The study was== supported by an epistemological framework of cultural historical activity theory and expansive learning. Realist social theory, emerging from critical realism, with its methodological compliment the morphogenetic framework gave the research the depth of detail required to explain how the expansive learning, organizational social change, and boundary crossings that are necessary for assembling the collective were taking place. This provided ontological depth to the research. The research found that expansive learning processes, which are also social learning processes (hence we use the term ‘expansive social learning’, supported organizational learning and development for improved wetland management. Five types of changes emerged from the research: (1) Changes in structure, (2) changes in practice, (3) changes in approach, (4) changes in discourse, and (5) changes in knowledge, values, and thinking. The study was able to explain how these changes occurred via the interaction of structural emergent properties and powers; cultural emergent properties and powers; and personal emergent properties and powers of agents. It was concluded that expansive learning could provide an environmental education platform to proactively work with the sociological potential of morphogenesis to bring about future change via an open-ended participatory and reflexive expansive learning process.
- Full Text:
- Date Issued: 2019
- Authors: Lindley, David S , Lotz-Sisitka, Heila
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182450 , vital:43831 , xlink:href="https://doi.org/10.3390/su11154230"
- Description: This study (conducted as PhD research at Rhodes University, South Africa) describes a formative interventionist research project conducted to explore factors inhibiting improved wetland management within a corporate plantation forestry context and determine if, and how, expansive social learning processes could strengthen organizational learning and development to overcome these factors. A series of formative interventionist workshops and feedback meetings took place over three years; developing new knowledge amongst staff of Company X, and improved wetland management practices. Through the expansive learning process, the tensions and contradictions that emerged became generative, supporting expansive learning that was reflectively engaged with throughout the research period. The study was== supported by an epistemological framework of cultural historical activity theory and expansive learning. Realist social theory, emerging from critical realism, with its methodological compliment the morphogenetic framework gave the research the depth of detail required to explain how the expansive learning, organizational social change, and boundary crossings that are necessary for assembling the collective were taking place. This provided ontological depth to the research. The research found that expansive learning processes, which are also social learning processes (hence we use the term ‘expansive social learning’, supported organizational learning and development for improved wetland management. Five types of changes emerged from the research: (1) Changes in structure, (2) changes in practice, (3) changes in approach, (4) changes in discourse, and (5) changes in knowledge, values, and thinking. The study was able to explain how these changes occurred via the interaction of structural emergent properties and powers; cultural emergent properties and powers; and personal emergent properties and powers of agents. It was concluded that expansive learning could provide an environmental education platform to proactively work with the sociological potential of morphogenesis to bring about future change via an open-ended participatory and reflexive expansive learning process.
- Full Text:
- Date Issued: 2019
Explaining people's perceptions of invasive alien species: A conceptual framework
- Shackleton, Ross T, Richardson, David M, Shackleton, Charlie M, Bennett, Brett, Crowley, Sarah L, Dehnen-Schmutz, Katharina, Estévez, Rodrigo A, Fischer, Anke, Kueffer, Christoph, Kull, Christian, Marchante, Elizabete, Novoa, Ana, Potgieter, Luke J, Vass, Jetske, Vas, Anna S, Larson, Brendon
- Authors: Shackleton, Ross T , Richardson, David M , Shackleton, Charlie M , Bennett, Brett , Crowley, Sarah L , Dehnen-Schmutz, Katharina , Estévez, Rodrigo A , Fischer, Anke , Kueffer, Christoph , Kull, Christian , Marchante, Elizabete , Novoa, Ana , Potgieter, Luke J , Vass, Jetske , Vas, Anna S , Larson, Brendon
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181356 , vital:43726 , xlink:href="https://doi.org/10.1016/j.jenvman.2018.04.045"
- Description: Human perceptions of nature and the environment are increasingly being recognised as important for environmental management and conservation. Understanding people's perceptions is crucial for understanding behaviour and developing effective management strategies to maintain, preserve and improve biodiversity, ecosystem services and human well-being. As an interdisciplinary team, we produced a synthesis of the key factors that influence people's perceptions of invasive alien species, and ordered them in a conceptual framework. In a context of considerable complexity and variation across time and space, we identified six broad-scale dimensions: (1) attributes of the individual perceiving the invasive alien species; (2) characteristics of the invasive alien species itself; (3) effects of the invasion (including negative and positive impacts, i.e. benefits and costs); (4) socio-cultural context; (5) landscape context; and (6) institutional and policy context. A number of underlying and facilitating aspects for each of these six overarching dimensions are also identified and discussed. Synthesising and understanding the main factors that influence people's perceptions is useful to guide future research, to facilitate dialogue and negotiation between actors, and to aid management and policy formulation and governance of invasive alien species. This can help to circumvent and mitigate conflicts, support prioritisation plans, improve stakeholder engagement platforms, and implement control measures.
- Full Text:
- Date Issued: 2019
- Authors: Shackleton, Ross T , Richardson, David M , Shackleton, Charlie M , Bennett, Brett , Crowley, Sarah L , Dehnen-Schmutz, Katharina , Estévez, Rodrigo A , Fischer, Anke , Kueffer, Christoph , Kull, Christian , Marchante, Elizabete , Novoa, Ana , Potgieter, Luke J , Vass, Jetske , Vas, Anna S , Larson, Brendon
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181356 , vital:43726 , xlink:href="https://doi.org/10.1016/j.jenvman.2018.04.045"
- Description: Human perceptions of nature and the environment are increasingly being recognised as important for environmental management and conservation. Understanding people's perceptions is crucial for understanding behaviour and developing effective management strategies to maintain, preserve and improve biodiversity, ecosystem services and human well-being. As an interdisciplinary team, we produced a synthesis of the key factors that influence people's perceptions of invasive alien species, and ordered them in a conceptual framework. In a context of considerable complexity and variation across time and space, we identified six broad-scale dimensions: (1) attributes of the individual perceiving the invasive alien species; (2) characteristics of the invasive alien species itself; (3) effects of the invasion (including negative and positive impacts, i.e. benefits and costs); (4) socio-cultural context; (5) landscape context; and (6) institutional and policy context. A number of underlying and facilitating aspects for each of these six overarching dimensions are also identified and discussed. Synthesising and understanding the main factors that influence people's perceptions is useful to guide future research, to facilitate dialogue and negotiation between actors, and to aid management and policy formulation and governance of invasive alien species. This can help to circumvent and mitigate conflicts, support prioritisation plans, improve stakeholder engagement platforms, and implement control measures.
- Full Text:
- Date Issued: 2019
Exploring and expanding transdisciplinary research for sustainable and just natural resource management
- Finca, Andiswa, Wolff, Margaret G, Cockburn, Jessica J, de Wet, Christopher J, Bezerra, Joana C, Weaver, Matthew J T, de Vos, Alta, Ralekhetla, Mateboho M, Libala, Notiswa, Mkabile, Qawekazi B, Odume, Nelson O, Palmer, Carolyn G
- Authors: Finca, Andiswa , Wolff, Margaret G , Cockburn, Jessica J , de Wet, Christopher J , Bezerra, Joana C , Weaver, Matthew J T , de Vos, Alta , Ralekhetla, Mateboho M , Libala, Notiswa , Mkabile, Qawekazi B , Odume, Nelson O , Palmer, Carolyn G
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416307 , vital:71337 , xlink:href="https://doi.org/10.5751/ES-11077-240414"
- Description: Transdisciplinarity is gaining acceptance in sustainability science research as an approach to work across disparate types of knowledge and practices in order to tackle complex social-ecological problems. On paper, transdisciplinarity appears to be substantially helpful, but in practice, participants may remain voiceless and disadvantaged. In this paper, we retrospectively investigate four case studies using recent design principles for transdisciplinary research, to explore a deeper understanding of the practical successes and failures of transdisciplinary research engagement. We show that the transdisciplinary way of working is time consuming, challenging, and insists that researchers and participants contribute reflexively. Careful attention to research design and methodology is central. The acceptance that complexity renders knowledge provisional, and complete honesty about the purpose of the research are critical to building relationships between researchers and participants. Gaining an understanding of the values people hold influences the research process and the possible outcomes toward sustainable and just natural resource management. We suggest that in order to enable sustainable and just natural resource management, transdisciplinary research should include values and ethics in the design, implementation, and reporting of projects.
- Full Text:
- Date Issued: 2019
- Authors: Finca, Andiswa , Wolff, Margaret G , Cockburn, Jessica J , de Wet, Christopher J , Bezerra, Joana C , Weaver, Matthew J T , de Vos, Alta , Ralekhetla, Mateboho M , Libala, Notiswa , Mkabile, Qawekazi B , Odume, Nelson O , Palmer, Carolyn G
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416307 , vital:71337 , xlink:href="https://doi.org/10.5751/ES-11077-240414"
- Description: Transdisciplinarity is gaining acceptance in sustainability science research as an approach to work across disparate types of knowledge and practices in order to tackle complex social-ecological problems. On paper, transdisciplinarity appears to be substantially helpful, but in practice, participants may remain voiceless and disadvantaged. In this paper, we retrospectively investigate four case studies using recent design principles for transdisciplinary research, to explore a deeper understanding of the practical successes and failures of transdisciplinary research engagement. We show that the transdisciplinary way of working is time consuming, challenging, and insists that researchers and participants contribute reflexively. Careful attention to research design and methodology is central. The acceptance that complexity renders knowledge provisional, and complete honesty about the purpose of the research are critical to building relationships between researchers and participants. Gaining an understanding of the values people hold influences the research process and the possible outcomes toward sustainable and just natural resource management. We suggest that in order to enable sustainable and just natural resource management, transdisciplinary research should include values and ethics in the design, implementation, and reporting of projects.
- Full Text:
- Date Issued: 2019
Exploring group solidarity for insights into qualities of T-learning
- Mudokwani, Kuda, Mukute, Mutizwa
- Authors: Mudokwani, Kuda , Mukute, Mutizwa
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/390612 , vital:68568 , xlink:href="https://doi.org/10.3390/su11236825"
- Description: Across the world, organised groups of farmers participating in just and sustainability transformations encounter multiple obstacles. Through solidarity manifested in iterative processes of questioning, co-learning, collective action and reflection, and value creation for themselves and for others, some succeed in overcoming them. This article investigates how a district organic farmer association in Zimbabwe is encountering and handling group solidarity challenges arising from shifting from local to district level coordinated organic production and marketing. Based on the use of change laboratory, this paper explores solidarity at the local niche and networked district level to seek insights into the qualities of T-learning.
- Full Text:
- Date Issued: 2019
- Authors: Mudokwani, Kuda , Mukute, Mutizwa
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/390612 , vital:68568 , xlink:href="https://doi.org/10.3390/su11236825"
- Description: Across the world, organised groups of farmers participating in just and sustainability transformations encounter multiple obstacles. Through solidarity manifested in iterative processes of questioning, co-learning, collective action and reflection, and value creation for themselves and for others, some succeed in overcoming them. This article investigates how a district organic farmer association in Zimbabwe is encountering and handling group solidarity challenges arising from shifting from local to district level coordinated organic production and marketing. Based on the use of change laboratory, this paper explores solidarity at the local niche and networked district level to seek insights into the qualities of T-learning.
- Full Text:
- Date Issued: 2019
Fabrication of efficient nonlinear optical absorber using Zn phthalocyanine-semiconductor quantum dots conjugates
- Mgidlana, Sithi, Oluwole, David O, Nyokong, Tebello
- Authors: Mgidlana, Sithi , Oluwole, David O , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187496 , vital:44663 , xlink:href="https://doi.org/10.1016/j.poly.2018.11.024"
- Description: In this paper, we report on the synthesis of Zn(II) phthalocyanine derivatives and their conjugates with core/shell and core/shell/shell semiconductor quantum dots (SQDs). Zn(II) mono amino-carboxyethylphenoxy phthalocyanine (1), Zn(II) mono 3-carboxyphenoxy-tris(pyridin-2-yloxy) phthalocyanine (2) and Zn(II) mono aminophenoxy-tris(benzothiazole) phthalocyanine (3) were synthesized. The photophysical and optical limiting properties of the phthalocyanine (Pc) complexes and their conjugates with SQDs were investigated in dimethyl sulfoxide. The optical limiting behaviour of the Pc complexes and their conjugates were measured by the open aperture Z-scan technique at laser excitation wavelength of 532 nm with 10 ns pulse. The conjugates outperformed the Pc complexes alone with the conjugates of 2-SQDs affording highest nonlinear absorption coefficient (βeff) value of ∼80 cm/GW and lowest limiting threshold (Ilim) value of ∼0.27 J·cm−2 as compared to other samples while complex 1 gave low βeff and high Ilim values of 42.2 cm/GW and 1.39 J·cm−2, respectively.
- Full Text:
- Date Issued: 2019
- Authors: Mgidlana, Sithi , Oluwole, David O , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187496 , vital:44663 , xlink:href="https://doi.org/10.1016/j.poly.2018.11.024"
- Description: In this paper, we report on the synthesis of Zn(II) phthalocyanine derivatives and their conjugates with core/shell and core/shell/shell semiconductor quantum dots (SQDs). Zn(II) mono amino-carboxyethylphenoxy phthalocyanine (1), Zn(II) mono 3-carboxyphenoxy-tris(pyridin-2-yloxy) phthalocyanine (2) and Zn(II) mono aminophenoxy-tris(benzothiazole) phthalocyanine (3) were synthesized. The photophysical and optical limiting properties of the phthalocyanine (Pc) complexes and their conjugates with SQDs were investigated in dimethyl sulfoxide. The optical limiting behaviour of the Pc complexes and their conjugates were measured by the open aperture Z-scan technique at laser excitation wavelength of 532 nm with 10 ns pulse. The conjugates outperformed the Pc complexes alone with the conjugates of 2-SQDs affording highest nonlinear absorption coefficient (βeff) value of ∼80 cm/GW and lowest limiting threshold (Ilim) value of ∼0.27 J·cm−2 as compared to other samples while complex 1 gave low βeff and high Ilim values of 42.2 cm/GW and 1.39 J·cm−2, respectively.
- 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, Macleod, Catriona I
- Authors: Saville Young, Lisa , Moodley, Dale , 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 , 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
First record of an indigenous South African parasitoid wasp on an imported biological control agent, the water hyacinth hopper
- Kraus, Emily C, Coetzee, Julie A, van Noort, Simon, Olmi, Massimo
- Authors: Kraus, Emily C , Coetzee, Julie A , van Noort, Simon , Olmi, Massimo
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417462 , vital:71455 , xlink:href="https://doi.org/10.1080/09583157.2019.1660306"
- Description: Water hyacinth, Pontederia crassipes (Martius) [≡Eichhornia crassip es (Martius) Solms-Laubach] (Pontederiaceae), is native to South America, but has expanded its range to many other regions of the world including South Africa. Megamelus scutellaris Berg (Hemiptera: Delphacidae) was released as a biological control agent and has established in several regions. Recently, the indigenous species Echthrodelphax migratorius Benoit, (Hymenoptera: Dryinidae) was discovered in South Africa parasitising M. scutellaris. This newly discovered relationship might have repercussions for the efficacy of biological control of water hyacinth by the delphacid. The wasp may negatively impact M. scutellaris populations making it difficult for the agent to successfully manage the invasive weed. Contrarily, the parasitoid may be beneficial by keeping the M. scutellaris populations stable, serving as a natural enemy.
- Full Text:
- Date Issued: 2019
- Authors: Kraus, Emily C , Coetzee, Julie A , van Noort, Simon , Olmi, Massimo
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417462 , vital:71455 , xlink:href="https://doi.org/10.1080/09583157.2019.1660306"
- Description: Water hyacinth, Pontederia crassipes (Martius) [≡Eichhornia crassip es (Martius) Solms-Laubach] (Pontederiaceae), is native to South America, but has expanded its range to many other regions of the world including South Africa. Megamelus scutellaris Berg (Hemiptera: Delphacidae) was released as a biological control agent and has established in several regions. Recently, the indigenous species Echthrodelphax migratorius Benoit, (Hymenoptera: Dryinidae) was discovered in South Africa parasitising M. scutellaris. This newly discovered relationship might have repercussions for the efficacy of biological control of water hyacinth by the delphacid. The wasp may negatively impact M. scutellaris populations making it difficult for the agent to successfully manage the invasive weed. Contrarily, the parasitoid may be beneficial by keeping the M. scutellaris populations stable, serving as a natural enemy.
- Full Text:
- Date Issued: 2019
Fluorescence “turn-ON” nanosensor for cyanide ion using supramolecular hybrid of graphene quantum dots and cobalt pyrene-derivatized phthalocyanine
- Achadu, Ojodomo John, Nyokong, Tebello
- Authors: Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187594 , vital:44674 , xlink:href="https://doi.org/10.1016/j.dyepig.2018.08.038"
- Description: A functional hybrid of graphene quantum dots (GQDs) and cobalt pyrene-derivatized phthalocyanine (CoPc) used as a sensitive nanoprobe for the recognition of cyanide ion (CN−) is described in this work. The fluorescence of GQDs was quenched upon non-covalent (π-π stacking) hybrid formation with CoPc via a possible energy transfer pathway. However, in the presence of CN−, the interaction between GQDs and CoPc was perturbed, such that the fluorescence of GQDs initially quenched by CoPc was found to be efficiently recovered in the presence of CN−. Amongst the molecules and anions tested to ascertain their effects on the fluorescence behaviour of the hybrid, only CN− ion induced the tunable “off-on” restoration of the fluorescence of GQDs, which demonstrates the selectivity of the hybrid towards CN−. The restored fluorescence signals of the GQDs were linearly modulated by different concentrations of CN− and were used for the quantitative assay of CN− with high sensitivity coupled with rapid detection time. The detection was in the linear range of 1.0–50.0 nM with limits of detection (LOD) of 0.5 nM. The analysis of spiked samples for the recovery of CN− further demonstrated the applicability of the hybrid for the satisfactory detection of the target analyte.
- Full Text:
- Date Issued: 2019
- Authors: Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187594 , vital:44674 , xlink:href="https://doi.org/10.1016/j.dyepig.2018.08.038"
- Description: A functional hybrid of graphene quantum dots (GQDs) and cobalt pyrene-derivatized phthalocyanine (CoPc) used as a sensitive nanoprobe for the recognition of cyanide ion (CN−) is described in this work. The fluorescence of GQDs was quenched upon non-covalent (π-π stacking) hybrid formation with CoPc via a possible energy transfer pathway. However, in the presence of CN−, the interaction between GQDs and CoPc was perturbed, such that the fluorescence of GQDs initially quenched by CoPc was found to be efficiently recovered in the presence of CN−. Amongst the molecules and anions tested to ascertain their effects on the fluorescence behaviour of the hybrid, only CN− ion induced the tunable “off-on” restoration of the fluorescence of GQDs, which demonstrates the selectivity of the hybrid towards CN−. The restored fluorescence signals of the GQDs were linearly modulated by different concentrations of CN− and were used for the quantitative assay of CN− with high sensitivity coupled with rapid detection time. The detection was in the linear range of 1.0–50.0 nM with limits of detection (LOD) of 0.5 nM. The analysis of spiked samples for the recovery of CN− further demonstrated the applicability of the hybrid for the satisfactory detection of the target analyte.
- Full Text:
- Date Issued: 2019
Food insecurity in South Africa: To what extent can social grants and consumption of wild foods eradicate hunger?
- Chakona, Gamuchirai, Shackleton, Charlie M
- Authors: Chakona, Gamuchirai , Shackleton, Charlie M
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/179541 , vital:43081 , xlink:href="https://doi.org/10.1016/j.wdp.2019.02.001"
- Description: As the world continues to face widespread food insecurity, achieving food security for all at all times is increasingly complicated. In South Africa, social grants and the use of wild foods have been reported as some ways to improve household food insecurity and reduce poverty. The study examined if social grants and consumption of wild foods alleviate food insecurity in South Africa. Household surveys and focus group discussions were conducted along the rural-urban continuum in three South African towns situated along an agro-ecological gradient. We explored the differences in household food security indicators, mean monthly food expenditure and wealth index between households receiving social grants, households consuming wild foods, and those who did not. Households receiving social grants were more food insecure with lower mean monthly food expenditure and wealth index than those who did not. Overall all towns, the use of wild foods improved household food security which was not true within towns where wild foods were mostly consumed by low income and more food insecure households. Social grants alone cannot eradicate food insecurity as the money is not enough to cater for all household needs whilst wild foods can potentially alleviate household food insecurity. As food prices continue to increase gradually and worsening household food insecurity, ways to shift ‘income circumstances’ of households and promote the use and consumption of wild foods which may increase dietary diversity and diversifying food access. Focus should be placed on capacity building, employment creation and promoting awareness on own food production which is one way to improve food security of poor households rather than depending on purchases from the grant money alone.
- Full Text:
- Date Issued: 2019
- Authors: Chakona, Gamuchirai , Shackleton, Charlie M
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/179541 , vital:43081 , xlink:href="https://doi.org/10.1016/j.wdp.2019.02.001"
- Description: As the world continues to face widespread food insecurity, achieving food security for all at all times is increasingly complicated. In South Africa, social grants and the use of wild foods have been reported as some ways to improve household food insecurity and reduce poverty. The study examined if social grants and consumption of wild foods alleviate food insecurity in South Africa. Household surveys and focus group discussions were conducted along the rural-urban continuum in three South African towns situated along an agro-ecological gradient. We explored the differences in household food security indicators, mean monthly food expenditure and wealth index between households receiving social grants, households consuming wild foods, and those who did not. Households receiving social grants were more food insecure with lower mean monthly food expenditure and wealth index than those who did not. Overall all towns, the use of wild foods improved household food security which was not true within towns where wild foods were mostly consumed by low income and more food insecure households. Social grants alone cannot eradicate food insecurity as the money is not enough to cater for all household needs whilst wild foods can potentially alleviate household food insecurity. As food prices continue to increase gradually and worsening household food insecurity, ways to shift ‘income circumstances’ of households and promote the use and consumption of wild foods which may increase dietary diversity and diversifying food access. Focus should be placed on capacity building, employment creation and promoting awareness on own food production which is one way to improve food security of poor households rather than depending on purchases from the grant money alone.
- Full Text:
- Date Issued: 2019
Food web structure and trophic dynamics of a fish community in an ephemeral floodplain lake
- Peel, Richard A, Hill, Jaclyn M, Taylor, Geraldine C, Weyl, Olaf L F
- Authors: Peel, Richard A , Hill, Jaclyn M , Taylor, Geraldine C , Weyl, Olaf L F
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444690 , vital:74260 , https://doi.org/10.3389/fenvs.2019.00192
- Description: In Africa, wetlands, such as shallow, ephemeral lakes provide ecosystem services, such as water purification, food supply, and flood control but are subject to dynamic flooding/drying cycles which vary in duration from years to decades. The stochastic nature of drying events subjects ephemeral lake fauna to persistent disturbance regimes, therefore understanding how biota respond to flooding and drying events is essential for their conservation and management. Primary production sources supporting consumer biomass in the shallow ephemeral Lake Liambezi (upper Zambezi Ecoregion), were investigated using stable isotope analysis, mixing models and stomach content analysis to investigate the following hypotheses: (1) algal primary production supports a higher consumer biomass than aquatic macrophytes; (2) the lake food chain is short, because the majority of fish fauna are detritivorous/herbivorous cichlids that are consumed by top predators; (3) fish community trophic structure will be similar between years; and (4) with short food chains and stochastic resource availability, there will be substantial competition for food among fish species.
- Full Text:
- Date Issued: 2019
- Authors: Peel, Richard A , Hill, Jaclyn M , Taylor, Geraldine C , Weyl, Olaf L F
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444690 , vital:74260 , https://doi.org/10.3389/fenvs.2019.00192
- Description: In Africa, wetlands, such as shallow, ephemeral lakes provide ecosystem services, such as water purification, food supply, and flood control but are subject to dynamic flooding/drying cycles which vary in duration from years to decades. The stochastic nature of drying events subjects ephemeral lake fauna to persistent disturbance regimes, therefore understanding how biota respond to flooding and drying events is essential for their conservation and management. Primary production sources supporting consumer biomass in the shallow ephemeral Lake Liambezi (upper Zambezi Ecoregion), were investigated using stable isotope analysis, mixing models and stomach content analysis to investigate the following hypotheses: (1) algal primary production supports a higher consumer biomass than aquatic macrophytes; (2) the lake food chain is short, because the majority of fish fauna are detritivorous/herbivorous cichlids that are consumed by top predators; (3) fish community trophic structure will be similar between years; and (4) with short food chains and stochastic resource availability, there will be substantial competition for food among fish species.
- Full Text:
- Date Issued: 2019
From academic to political rigour: Insights from the ‘Tarot’ of transgressive research
- Temper, Leah, McGarry, Dylan K, Weber, Lena
- Authors: Temper, Leah , McGarry, Dylan K , Weber, Lena
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/390629 , vital:68570 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/186598"
- Description: The role of science and knowledge production is at a crossroads, as societal transformation calls for challenging dominant forms of knowledge production that have contributed to marginalizing other ways of knowing. This presents a challenge to mainstream science and invites a deeper reflection on our roles as scientists and exploration of alternative engaged, post-normal and activist approaches to research. This paper examines the diverse ways researchers are meeting this challenge. Employing the device of the Tarot deck we describe seven “characters” to illustrate the variety of roles and approaches that trans-disciplinary, transformative, transgressive and activist researchers are engaging in. These characters are used to introduce and develop the concept of political rigour as a means of expanded academic rigour in new emancipatory scientific paradigms. We demonstrate how these Tarot characters can be used as an activity for collective and personal reflexivity and propose ten principles that frequently emerge in a ‘political’ peer review process. We argue that the insights emerging from these strands of radical, critical, engaged and applied forms of scholarship, can significantly improve the understanding of what a “transformative knowledge paradigm” may look like in practice and how it can be mobilized for social change and environmental justice.
- Full Text:
- Date Issued: 2019
- Authors: Temper, Leah , McGarry, Dylan K , Weber, Lena
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/390629 , vital:68570 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/186598"
- Description: The role of science and knowledge production is at a crossroads, as societal transformation calls for challenging dominant forms of knowledge production that have contributed to marginalizing other ways of knowing. This presents a challenge to mainstream science and invites a deeper reflection on our roles as scientists and exploration of alternative engaged, post-normal and activist approaches to research. This paper examines the diverse ways researchers are meeting this challenge. Employing the device of the Tarot deck we describe seven “characters” to illustrate the variety of roles and approaches that trans-disciplinary, transformative, transgressive and activist researchers are engaging in. These characters are used to introduce and develop the concept of political rigour as a means of expanded academic rigour in new emancipatory scientific paradigms. We demonstrate how these Tarot characters can be used as an activity for collective and personal reflexivity and propose ten principles that frequently emerge in a ‘political’ peer review process. We argue that the insights emerging from these strands of radical, critical, engaged and applied forms of scholarship, can significantly improve the understanding of what a “transformative knowledge paradigm” may look like in practice and how it can be mobilized for social change and environmental justice.
- Full Text:
- Date Issued: 2019
Grasses as suitable targets for classical weed biological control
- Sutton, Guy F, Day, Michael D, Den Breeyen, Alana, Goolsby, J A, Cristofaro, M, McConnachie, Andrew J, Paterson, Iain D
- Authors: Sutton, Guy F , Day, Michael D , Den Breeyen, Alana , Goolsby, J A , Cristofaro, M , McConnachie, Andrew J , Paterson, Iain D
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417984 , vital:71499 , xlink:href="https://doi.org/10.1007/s10526-019-09968-8"
- Description: Grasses are amongst the most abundant and environmentally damaging invasive weeds worldwide. Biological control is frequently employed as a sustainable and cost-effective management strategy for many weeds. However, grasses have not been actively pursued as targets for classical weed biological control due to a perceived lack of sufficiently specialised and damaging natural enemies to use as biological control agents. There are also concerns that the risk posed to economically important crop/pasture species and closely-related native species is too great to consider implementing biological control for invasive grasses. In this paper, we review the literature and demonstrate that grasses can possess suitably host-specific and damaging natural enemies to warrant consideration as potential biological control agents. The risk of grass biological control is no greater than for other weedy taxa if practitioners follow appropriately rigorous risk assessments protocols.
- Full Text:
- Date Issued: 2019
- Authors: Sutton, Guy F , Day, Michael D , Den Breeyen, Alana , Goolsby, J A , Cristofaro, M , McConnachie, Andrew J , Paterson, Iain D
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417984 , vital:71499 , xlink:href="https://doi.org/10.1007/s10526-019-09968-8"
- Description: Grasses are amongst the most abundant and environmentally damaging invasive weeds worldwide. Biological control is frequently employed as a sustainable and cost-effective management strategy for many weeds. However, grasses have not been actively pursued as targets for classical weed biological control due to a perceived lack of sufficiently specialised and damaging natural enemies to use as biological control agents. There are also concerns that the risk posed to economically important crop/pasture species and closely-related native species is too great to consider implementing biological control for invasive grasses. In this paper, we review the literature and demonstrate that grasses can possess suitably host-specific and damaging natural enemies to warrant consideration as potential biological control agents. The risk of grass biological control is no greater than for other weedy taxa if practitioners follow appropriately rigorous risk assessments protocols.
- Full Text:
- Date Issued: 2019
Green synthesis of zinc oxide nanoparticles using Solanum torvum (L) leaf extract and evaluation of the toxicological profile of the ZnO nanoparticles–hydrogel composite in Wistar albino rats
- Ezealisiji, Kenneth E, Siwe-Noundou, Xavier, Maduelosi, Blessing, Nwachukwu, Nkemakolam, Krause, Rui W M
- Authors: Ezealisiji, Kenneth E , Siwe-Noundou, Xavier , Maduelosi, Blessing , Nwachukwu, Nkemakolam , Krause, Rui W M
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/194015 , vital:45416 , xlink:href="https://doi.org/10.1007/s40089-018-0263-1"
- Description: Current study reports a simple and one-pot synthesis of zinc oxide nanoparticles (ZnONPs) using an aqueous extract of Solanum torvum and evaluation of its toxicological profile (0.5% w/w and 1.0% w/w) in Wistar albino rats with respect to the biochemical index. The nanoparticles were characterized using ultraviolet–visible spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction technique. Dynamic light scattering (DLS) and zeta potential of synthesized nanoparticles were analyzed to know the average size and stability of particles. Synthesized nanoparticles were stable, discreet, and mostly spherical, and size of particles was within the nanometre range. Biochemical markers of hepatic and renal functions were measured. Zinc oxide nanoparticles significantly decreased serum uric acid level (p less than 0.001) in a dose-dependent manner, while the serum alkaline phosphatase level was increased at the two test doses. The level of alanine transaminase was increased after exposure for 28 days (p less than 0.05). This study concludes that biogenic zinc oxide nanoparticles-infused hydrogel applied dermatologically could affect hepatic and renal performance in rats, and there was an observed cumulative toxicological effect with time of exposure.
- Full Text:
- Date Issued: 2019
- Authors: Ezealisiji, Kenneth E , Siwe-Noundou, Xavier , Maduelosi, Blessing , Nwachukwu, Nkemakolam , Krause, Rui W M
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/194015 , vital:45416 , xlink:href="https://doi.org/10.1007/s40089-018-0263-1"
- Description: Current study reports a simple and one-pot synthesis of zinc oxide nanoparticles (ZnONPs) using an aqueous extract of Solanum torvum and evaluation of its toxicological profile (0.5% w/w and 1.0% w/w) in Wistar albino rats with respect to the biochemical index. The nanoparticles were characterized using ultraviolet–visible spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction technique. Dynamic light scattering (DLS) and zeta potential of synthesized nanoparticles were analyzed to know the average size and stability of particles. Synthesized nanoparticles were stable, discreet, and mostly spherical, and size of particles was within the nanometre range. Biochemical markers of hepatic and renal functions were measured. Zinc oxide nanoparticles significantly decreased serum uric acid level (p less than 0.001) in a dose-dependent manner, while the serum alkaline phosphatase level was increased at the two test doses. The level of alanine transaminase was increased after exposure for 28 days (p less than 0.05). This study concludes that biogenic zinc oxide nanoparticles-infused hydrogel applied dermatologically could affect hepatic and renal performance in rats, and there was an observed cumulative toxicological effect with time of exposure.
- Full Text:
- Date Issued: 2019
High throughput screening, docking, and molecular dynamics studies to identify potential inhibitors of human calcium/calmodulin-dependent protein kinase IV
- Beg, Anam, Khan, Faez I, Lobb, Kevin, Islam, Asimul, Ahmad, Faizan, Hassan, M Imtaiyaz
- Authors: Beg, Anam , Khan, Faez I , Lobb, Kevin , Islam, Asimul , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:74587 , xlink:href="https://doi.org/10.1080/07391102.2018.1479310"
- Description: Calcium/calmodulin-dependent protein kinase IV (CAMKIV) is associated with many diseases including cancer and neurodegenerative disorders and thus being considered as a potential drug target. Here, we have employed the knowledge of three-dimensional structure of CAMKIV to identify new inhibitors for possible therapeutic intervention. We have employed virtual high throughput screening of 12,500 natural compounds of Zinc database to screen the best possible inhibitors of CAMKIV. Subsequently, 40 compounds which showed significant docking scores (−11.6 to −10.0 kcal/mol) were selected and further filtered through Lipinski rule and drug likeness parameter to get best inhibitors of CAMKIV. Docking results are indicating that ligands are binding to the hydrophobic cavity of the kinase domain of CAMKIV and forming a significant number of non-covalent interactions. Four compounds, ZINC02098378, ZINC12866674, ZINC04293413, and ZINC13403020, showing excellent binding affinity and drug likeness were subjected to molecular dynamics simulation to evaluate their mechanism of interaction and stability of protein-ligand complex. Our observations clearly suggesting that these selected ligands may be further employed for therapeutic intervention to address CAMKIV associated diseases.
- Full Text:
- Date Issued: 2019
- Authors: Beg, Anam , Khan, Faez I , Lobb, Kevin , Islam, Asimul , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:74587 , xlink:href="https://doi.org/10.1080/07391102.2018.1479310"
- Description: Calcium/calmodulin-dependent protein kinase IV (CAMKIV) is associated with many diseases including cancer and neurodegenerative disorders and thus being considered as a potential drug target. Here, we have employed the knowledge of three-dimensional structure of CAMKIV to identify new inhibitors for possible therapeutic intervention. We have employed virtual high throughput screening of 12,500 natural compounds of Zinc database to screen the best possible inhibitors of CAMKIV. Subsequently, 40 compounds which showed significant docking scores (−11.6 to −10.0 kcal/mol) were selected and further filtered through Lipinski rule and drug likeness parameter to get best inhibitors of CAMKIV. Docking results are indicating that ligands are binding to the hydrophobic cavity of the kinase domain of CAMKIV and forming a significant number of non-covalent interactions. Four compounds, ZINC02098378, ZINC12866674, ZINC04293413, and ZINC13403020, showing excellent binding affinity and drug likeness were subjected to molecular dynamics simulation to evaluate their mechanism of interaction and stability of protein-ligand complex. Our observations clearly suggesting that these selected ligands may be further employed for therapeutic intervention to address CAMKIV associated diseases.
- Full Text:
- Date Issued: 2019
Identification and evaluation of bioactive natural products as potential inhibitors of human microtubule affinity-regulating kinase 4 (MARK4)
- Mohammad, Taj, Khan, Faez I, Lobb, Kevin, Islam, Asimul, Ahmad, Faizan, Hassan, M Imtaiyaz
- Authors: Mohammad, Taj , Khan, Faez I , Lobb, Kevin , Islam, Asimul , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447159 , vital:74588 , xlink:href="https://doi.org/10.1080/07391102.2018.1468282"
- Description: Microtubule affinity-regulating kinase 4 (MARK4) has recently been identified as a potential drug target for several complex diseases including cancer, diabetes and neurodegenerative disorders. Inhibition of MARK4 activity is an appealing therapeutic option to treat such diseases. Here, we have performed structure-based virtual high-throughput screening of 100,000 naturally occurring compounds from ZINC database against MARK4 to find its potential inhibitors. The resulted hits were selected, based on the binding affinities, docking scores and selectivity. Further, binding energy calculation, Lipinski filtration and ADMET prediction were carried out to find safe and better hits against MARK4. Best 10 compounds bearing high specificity and binding efficiency were selected, and their binding pattern to MARK4 was analyzed in detail. Finally, 100 ns molecular dynamics simulation was performed to evaluate; the dynamics stability of MARK4-compound complex. In conclusion, these selected natural compounds from ZINC database might be potential leads against MARK4, and can further be exploited in drug design and development for associated diseases.
- Full Text:
- Date Issued: 2019
- Authors: Mohammad, Taj , Khan, Faez I , Lobb, Kevin , Islam, Asimul , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447159 , vital:74588 , xlink:href="https://doi.org/10.1080/07391102.2018.1468282"
- Description: Microtubule affinity-regulating kinase 4 (MARK4) has recently been identified as a potential drug target for several complex diseases including cancer, diabetes and neurodegenerative disorders. Inhibition of MARK4 activity is an appealing therapeutic option to treat such diseases. Here, we have performed structure-based virtual high-throughput screening of 100,000 naturally occurring compounds from ZINC database against MARK4 to find its potential inhibitors. The resulted hits were selected, based on the binding affinities, docking scores and selectivity. Further, binding energy calculation, Lipinski filtration and ADMET prediction were carried out to find safe and better hits against MARK4. Best 10 compounds bearing high specificity and binding efficiency were selected, and their binding pattern to MARK4 was analyzed in detail. Finally, 100 ns molecular dynamics simulation was performed to evaluate; the dynamics stability of MARK4-compound complex. In conclusion, these selected natural compounds from ZINC database might be potential leads against MARK4, and can further be exploited in drug design and development for associated diseases.
- Full Text:
- Date Issued: 2019
In vitro antimalarial, antitrypanosomal and HIV-1 integrase inhibitory activities of two Cameroonian medicinal plants
- Fouokeng, Yannick, Feumo Feusso, H M, Mbosso Teinkela, Jean E, Siwe-Noundou, Xavier, Wintjens, René T, Isaacs, Michelle, Hoppe, Heinrich, Krause, Rui W M, Azébazé, Anatole G B, Vardamides, Juliette C
- Authors: Fouokeng, Yannick , Feumo Feusso, H M , Mbosso Teinkela, Jean E , Siwe-Noundou, Xavier , Wintjens, René T , Isaacs, Michelle , Hoppe, Heinrich , Krause, Rui W M , Azébazé, Anatole G B , Vardamides, Juliette C
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/195014 , vital:45519 , xlink:href="https://doi.org/10.1016/j.sajb.2018.10.008"
- Description: Antiplasmodial, antitrypanosomal and anti-HIV-1 activities of crude extracts, fractions and some isolated compounds from two Cameroonian medicinal plants: Antrocaryon klaineanum Pierre (Anacardiaceae) and Diospyros conocarpa Gürke ex K. Schum. (Ebenaceae) were assessed. The phytochemical studies led to the isolation of eight compounds (1–8) from Diospyros conocarpa and six compounds (6, 9–13) from Antrocaryon klaineanum. These compounds were identified as mangiferolic acid (1), 3β, 22(S)-dihydroxycycloart-24E-en-26-oic acid (2), lupeol (3), aridanin (4), betulin (5), betulinic acid (6), bergenin (7), D-quercitol(8), entilin C(9), entilin A(10), antrocarine A(11), 7R,20(S)-dihydroxy-4,24(28)-ergostadien-3-one(12) and stigmasterol glucoside (13). The criteria for activity were set as follows: an IC50 value more than 10 μg/mL for crude extracts and more than 1 μg/mL for pure compounds. The hexane/ethyl acetate (1:1) fraction of A.klaineanum root bark (AKERF1) and the hexane/ethyl acetate (1:1) fraction of A.klaineanum trunk bark (AKETF1) presented the strongest antiplasmodial activities with IC50 values of 0.4 and 4.4 μg/mL, respectively. Aridanin (4) and antrocarine A(11), as well as the crude extract of D.conocarpa roots (EDCR), AKERF1 and AKETF1 showed moderate trypanocidal effects. The crude extract of A.klaineanum root bark (AKER) and AKETF1 exhibited attractive activities on HIV-1 integrase with IC50 values of 1.96 and 24.04 μg/mL, respectively. The results provide baseline information on the use of A.klaineanum and D.conocarpa extracts, as well as certain components, as sources of new antiplasmodial, antitrypanosomal and anti-HIV drugs.
- Full Text:
- Date Issued: 2019
- Authors: Fouokeng, Yannick , Feumo Feusso, H M , Mbosso Teinkela, Jean E , Siwe-Noundou, Xavier , Wintjens, René T , Isaacs, Michelle , Hoppe, Heinrich , Krause, Rui W M , Azébazé, Anatole G B , Vardamides, Juliette C
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/195014 , vital:45519 , xlink:href="https://doi.org/10.1016/j.sajb.2018.10.008"
- Description: Antiplasmodial, antitrypanosomal and anti-HIV-1 activities of crude extracts, fractions and some isolated compounds from two Cameroonian medicinal plants: Antrocaryon klaineanum Pierre (Anacardiaceae) and Diospyros conocarpa Gürke ex K. Schum. (Ebenaceae) were assessed. The phytochemical studies led to the isolation of eight compounds (1–8) from Diospyros conocarpa and six compounds (6, 9–13) from Antrocaryon klaineanum. These compounds were identified as mangiferolic acid (1), 3β, 22(S)-dihydroxycycloart-24E-en-26-oic acid (2), lupeol (3), aridanin (4), betulin (5), betulinic acid (6), bergenin (7), D-quercitol(8), entilin C(9), entilin A(10), antrocarine A(11), 7R,20(S)-dihydroxy-4,24(28)-ergostadien-3-one(12) and stigmasterol glucoside (13). The criteria for activity were set as follows: an IC50 value more than 10 μg/mL for crude extracts and more than 1 μg/mL for pure compounds. The hexane/ethyl acetate (1:1) fraction of A.klaineanum root bark (AKERF1) and the hexane/ethyl acetate (1:1) fraction of A.klaineanum trunk bark (AKETF1) presented the strongest antiplasmodial activities with IC50 values of 0.4 and 4.4 μg/mL, respectively. Aridanin (4) and antrocarine A(11), as well as the crude extract of D.conocarpa roots (EDCR), AKERF1 and AKETF1 showed moderate trypanocidal effects. The crude extract of A.klaineanum root bark (AKER) and AKETF1 exhibited attractive activities on HIV-1 integrase with IC50 values of 1.96 and 24.04 μg/mL, respectively. The results provide baseline information on the use of A.klaineanum and D.conocarpa extracts, as well as certain components, as sources of new antiplasmodial, antitrypanosomal and anti-HIV drugs.
- Full Text:
- Date Issued: 2019
Inhibition of aluminium corrosion using benzothiazole and its phthalocyanine derivative
- Nnaji, Nnaemeka, Nwaji, Njemuwa, Fomo, Gertrude, Mack, John, Nyokong, Tebello
- Authors: Nnaji, Nnaemeka , Nwaji, Njemuwa , Fomo, Gertrude , Mack, John , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186949 , vital:44550 , xlink:href="https://doi.org/10.1007/s12678-019-00538-1"
- Description: Cyclic voltammetry and potentiodynamic polarization techniques were used to study the effects of 4-[4-(1,3-benzothiazol2yl)phenoxy] phthalonitrile (BT) and tetrakis[(benzo[d]thiazol-2ylphenoxy) phthalocyaninato] gallium(III)chloride (ClGaBTPc) as aluminium corrosion inhibitors in 1.0 M hydrochloric acid. The presence of the inhibitors in the concentration range of 2 to 10 μM was found to retard the aluminium corrosion process such that the inhibition efficiency was found to range from 28.2 to 76.1% for BT and from 71.5 to 82.7% for ClGaBTPc. The latter was a better inhibitor. Scanning electron microscopy and energy-dispersive X-ray measurements reveal effective metal surface protection by the inhibitors, most probably by shielding it from the corrosion attacks of Cl− from the acid. The calculated quantum chemical parameters agreed with experimental results.
- Full Text:
- Date Issued: 2019
- Authors: Nnaji, Nnaemeka , Nwaji, Njemuwa , Fomo, Gertrude , Mack, John , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186949 , vital:44550 , xlink:href="https://doi.org/10.1007/s12678-019-00538-1"
- Description: Cyclic voltammetry and potentiodynamic polarization techniques were used to study the effects of 4-[4-(1,3-benzothiazol2yl)phenoxy] phthalonitrile (BT) and tetrakis[(benzo[d]thiazol-2ylphenoxy) phthalocyaninato] gallium(III)chloride (ClGaBTPc) as aluminium corrosion inhibitors in 1.0 M hydrochloric acid. The presence of the inhibitors in the concentration range of 2 to 10 μM was found to retard the aluminium corrosion process such that the inhibition efficiency was found to range from 28.2 to 76.1% for BT and from 71.5 to 82.7% for ClGaBTPc. The latter was a better inhibitor. Scanning electron microscopy and energy-dispersive X-ray measurements reveal effective metal surface protection by the inhibitors, most probably by shielding it from the corrosion attacks of Cl− from the acid. The calculated quantum chemical parameters agreed with experimental results.
- Full Text:
- Date Issued: 2019