Scenario development
- Hichert, Tanya, Biggs, Reinette, de Vos, Alta, Peterson, Garry
- Authors: Hichert, Tanya , Biggs, Reinette , de Vos, Alta , Peterson, Garry
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/433857 , vital:73005 , ISBN 9781000401516 , https://library.oapen.org/handle/20.500.12657/49560
- Description: Scenario development connects to various other methods, but in particular to futures analysis (Chapter 10) as it is also regarded as a futures analysis method. It warrants a separate chapter in addition to the other futures analysis methods (described in Chapter 10) because of its importance and widespread use. Scenario development also connects to facilitated dialogues (Chapter 9), serious games (Chapter 12), participatory modelling and planning (Chapter 13), dynamical systems modelling (Chapter 26) and agent-based modelling (Chapter 28).
- Full Text:
- Date Issued: 2021
- Authors: Hichert, Tanya , Biggs, Reinette , de Vos, Alta , Peterson, Garry
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/433857 , vital:73005 , ISBN 9781000401516 , https://library.oapen.org/handle/20.500.12657/49560
- Description: Scenario development connects to various other methods, but in particular to futures analysis (Chapter 10) as it is also regarded as a futures analysis method. It warrants a separate chapter in addition to the other futures analysis methods (described in Chapter 10) because of its importance and widespread use. Scenario development also connects to facilitated dialogues (Chapter 9), serious games (Chapter 12), participatory modelling and planning (Chapter 13), dynamical systems modelling (Chapter 26) and agent-based modelling (Chapter 28).
- Full Text:
- Date Issued: 2021
Sex, gender and Uvalo/Letswalo centred spirituality
- Magadla, Siphokazi, Magoqwana, Babalwa, Motsemme, Nthabiseng, Mohoto, Lieketso
- Authors: Magadla, Siphokazi , Magoqwana, Babalwa , Motsemme, Nthabiseng , Mohoto, Lieketso
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/298663 , vital:57725 , xlink:href="https://doi.org/10.1080/02589001.2021.1909711"
- Description: In Male Daughters, Female Husbands (1987) Amadiume argues that the female orientation of Nnobi society and its emphasis on female industriousness is ‘derived from goddess Idemili – the ancestral religious deity’ (27). While Christianity dominates the outlook and conservatism of the post-colonial African state, we are seeing a growing public presence of African spiritual practitioners in southern Africa. The interview with Lieketso Gogo Mapitsi Mohoto reflects on her journey of becoming a healer. She uses the concept of ‘uvalo' to argue for deeper connected spiritual awareness within this practice of healing. Using the Nguni concept of uvalo, she refers to the fluid meaning of intuition also known as Umbilini among Xhosa-speaking people, while Sesotho speakers call it Letswalo. This intimate connection with the Divine can sometimes mean a sense of fear for ordinary people, while it promotes a deep sense of knowing for the spiritually conscious. Gogo Mapitsi's connections between spirituality and land, speak to Amadiume’s matrifocal understanding of productivity as linked to the goddess Idemili in Nnobi histories. Gogo Mapitsi reminds us that the multiple health, economic, psychological crises we face today are linked 'to how uvalo works.' She tells us that the 'cultivation of that inner knowing and the cultivation of trust in that knowing' is central to how a Sangoma understands and responds to the needs of their society.
- Full Text:
- Date Issued: 2021
- Authors: Magadla, Siphokazi , Magoqwana, Babalwa , Motsemme, Nthabiseng , Mohoto, Lieketso
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/298663 , vital:57725 , xlink:href="https://doi.org/10.1080/02589001.2021.1909711"
- Description: In Male Daughters, Female Husbands (1987) Amadiume argues that the female orientation of Nnobi society and its emphasis on female industriousness is ‘derived from goddess Idemili – the ancestral religious deity’ (27). While Christianity dominates the outlook and conservatism of the post-colonial African state, we are seeing a growing public presence of African spiritual practitioners in southern Africa. The interview with Lieketso Gogo Mapitsi Mohoto reflects on her journey of becoming a healer. She uses the concept of ‘uvalo' to argue for deeper connected spiritual awareness within this practice of healing. Using the Nguni concept of uvalo, she refers to the fluid meaning of intuition also known as Umbilini among Xhosa-speaking people, while Sesotho speakers call it Letswalo. This intimate connection with the Divine can sometimes mean a sense of fear for ordinary people, while it promotes a deep sense of knowing for the spiritually conscious. Gogo Mapitsi's connections between spirituality and land, speak to Amadiume’s matrifocal understanding of productivity as linked to the goddess Idemili in Nnobi histories. Gogo Mapitsi reminds us that the multiple health, economic, psychological crises we face today are linked 'to how uvalo works.' She tells us that the 'cultivation of that inner knowing and the cultivation of trust in that knowing' is central to how a Sangoma understands and responds to the needs of their society.
- Full Text:
- Date Issued: 2021
Skills for communicating severe acute respiratory syndrome-coronavirus-2 result to patients and/or relatives
- Adeniyi, Oladele Vincent, Kayembe, Dominique K
- Authors: Adeniyi, Oladele Vincent , Kayembe, Dominique K
- Date: 2021
- Subjects: COVID-19 Structured model Medical consultation Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7236 , vital:53095 , xlink:href="https://doi.org/10.4102/safp.v63i1.5221"
- Description: Clinicians notify positive results of the severe acute respiratory syndrome coronavirus-2 polymerase chain reaction to patients and/or relatives, whilst short message service (SMS) has been adopted as a means of disseminating negative results. Therefore, clinicians should be adequately equipped to provide telephonic consultation whilst delivering a positive test result to patients. The news of the coronavirus disease 2019 (COVID-19) test result often invokes fear of impending death in patients, especially the elderlies and those with comorbidities. In addition, several survivors have reported persistent symptoms and COVID-19-related stigma, which precludes them from immediate re-integration into their workplaces. Consequently, COVID-19 results are perceived as bad news by the members of the public. This article justifies why COVID-19 test results are bad news and also discusses the notification steps to follow when delivering COVID-19 results, whilst also addressing patients’ immediate concerns. The article concludes by highlighting an important safety net for COVID-19 patients and the attending clinician.
- Full Text:
- Date Issued: 2021
- Authors: Adeniyi, Oladele Vincent , Kayembe, Dominique K
- Date: 2021
- Subjects: COVID-19 Structured model Medical consultation Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7236 , vital:53095 , xlink:href="https://doi.org/10.4102/safp.v63i1.5221"
- Description: Clinicians notify positive results of the severe acute respiratory syndrome coronavirus-2 polymerase chain reaction to patients and/or relatives, whilst short message service (SMS) has been adopted as a means of disseminating negative results. Therefore, clinicians should be adequately equipped to provide telephonic consultation whilst delivering a positive test result to patients. The news of the coronavirus disease 2019 (COVID-19) test result often invokes fear of impending death in patients, especially the elderlies and those with comorbidities. In addition, several survivors have reported persistent symptoms and COVID-19-related stigma, which precludes them from immediate re-integration into their workplaces. Consequently, COVID-19 results are perceived as bad news by the members of the public. This article justifies why COVID-19 test results are bad news and also discusses the notification steps to follow when delivering COVID-19 results, whilst also addressing patients’ immediate concerns. The article concludes by highlighting an important safety net for COVID-19 patients and the attending clinician.
- Full Text:
- Date Issued: 2021
Solar Driven Photocatalytic Activity of Porphyrin Sensitized TiO2
- Otieno, Sebastien, Lanterna, Anabel E, Mack, John, Derese, Solomon, Amuhaya, Edith K, Nyokong, Tebello, Scaiano, Juan C
- Authors: Otieno, Sebastien , Lanterna, Anabel E , Mack, John , Derese, Solomon , Amuhaya, Edith K , Nyokong, Tebello , Scaiano, Juan C
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190612 , vital:45010 , xlink:href="https://doi.org/10.3390/molecules26113131"
- Description: The absence of a secure long-term sustainable energy supply is recognized as a major worldwide technological challenge. The generation of H2 through photocatalysis is an environmentally friendly alternative that can help solve the energy problem. Thus, the development of semiconductor materials that can absorb solar light is an attractive approach. TiO2 has a wide bandgap that suffers from no activity in the visible spectrum, limiting its use of solar radiation. In this research, the semiconductor absorption profile was extended into the visible region of the solar spectrum by preparing porphyrin-TiO2 (P-TiO2 ) composites of meso-tetra(4-bromophenyl)porphyrin (PP1) and meso-tetra(5-bromo-2-thienyl)porphyrin (PP2) and their In(III), Zn(II) and Ga(III) metal complexes. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations were performed on the porphyrins to gain insight into their electron injection capability. The results demonstrate that P-TiO2 systems merit further in-depth study for applications that require efficient photocatalytic H2 generation.
- Full Text:
- Date Issued: 2021
- Authors: Otieno, Sebastien , Lanterna, Anabel E , Mack, John , Derese, Solomon , Amuhaya, Edith K , Nyokong, Tebello , Scaiano, Juan C
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190612 , vital:45010 , xlink:href="https://doi.org/10.3390/molecules26113131"
- Description: The absence of a secure long-term sustainable energy supply is recognized as a major worldwide technological challenge. The generation of H2 through photocatalysis is an environmentally friendly alternative that can help solve the energy problem. Thus, the development of semiconductor materials that can absorb solar light is an attractive approach. TiO2 has a wide bandgap that suffers from no activity in the visible spectrum, limiting its use of solar radiation. In this research, the semiconductor absorption profile was extended into the visible region of the solar spectrum by preparing porphyrin-TiO2 (P-TiO2 ) composites of meso-tetra(4-bromophenyl)porphyrin (PP1) and meso-tetra(5-bromo-2-thienyl)porphyrin (PP2) and their In(III), Zn(II) and Ga(III) metal complexes. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations were performed on the porphyrins to gain insight into their electron injection capability. The results demonstrate that P-TiO2 systems merit further in-depth study for applications that require efficient photocatalytic H2 generation.
- Full Text:
- Date Issued: 2021
Specialty Grand Challenges in Urban Agriculture: Ecological and Social Approaches to Sustainability Transformations
- Zimmerer, Karl S, Bell, Martha G, Chirisa, Innocent, Duvall, Chris S, Egerer, Monika, Hung, Po-Yi, Lerner, Amy M, Shackleton, Charlie M, Ward, James David, Yacamán Ochoa, Carolina
- Authors: Zimmerer, Karl S , Bell, Martha G , Chirisa, Innocent , Duvall, Chris S , Egerer, Monika , Hung, Po-Yi , Lerner, Amy M , Shackleton, Charlie M , Ward, James David , Yacamán Ochoa, Carolina
- Date: 2021
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175779 , vital:42623 , https://doi.org/10.3389/fsufs.2021.668561
- Description: This synopsis of the Grand Challenges of Urban Agriculture (UA) is framed by the urgent need to understand and strengthen the expanding yet highly diverse roles of UA amid rapid global urbanization, failures of predominant food systems, and crises in systems of physical and mental health. More than half of humanity lives in cities today and by 2030 this is projected to grow to 60.4 percent, ~5 billion people (UN Habitat, 2020). More than 90 percent of urban demographic increase is anticipated to take place in the developing world.
- Full Text:
- Date Issued: 2021
- Authors: Zimmerer, Karl S , Bell, Martha G , Chirisa, Innocent , Duvall, Chris S , Egerer, Monika , Hung, Po-Yi , Lerner, Amy M , Shackleton, Charlie M , Ward, James David , Yacamán Ochoa, Carolina
- Date: 2021
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175779 , vital:42623 , https://doi.org/10.3389/fsufs.2021.668561
- Description: This synopsis of the Grand Challenges of Urban Agriculture (UA) is framed by the urgent need to understand and strengthen the expanding yet highly diverse roles of UA amid rapid global urbanization, failures of predominant food systems, and crises in systems of physical and mental health. More than half of humanity lives in cities today and by 2030 this is projected to grow to 60.4 percent, ~5 billion people (UN Habitat, 2020). More than 90 percent of urban demographic increase is anticipated to take place in the developing world.
- Full Text:
- Date Issued: 2021
Strategies utilised in translating children’s stories from English into isiXhosa
- Authors: Madolo, Yolisa
- Date: 2021
- Subjects: Children Xhosa Grammar, Comparative and general--Ideophone Children, Black, in literature Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7010 , vital:52637 , xlink:href="https://doi.org/10.1080/02572117.2021.2010919"
- Description: Translation scholars suggest various strategies for dealing with equivalence and non-equivalence. These popular strategies address non-equivalence, the converse of equivalence, that is commonly found in translation. Nonequivalence is found at word, phrase, sentence, and pragmatic levels. Not a great deal of research has been done in the translation strategies used between English and South African indigenous languages. It is possible that these languages employ some strategies that are not listed under current, popular strategies. These strategies may be necessitated by the linguistic and historical differences between English and African languages. For instance, what is acceptable in question form in English might be more suitable as a statement in African languages, specifically isiXhosa. The strategies to be presented are from an ongoing study of selected children’s stories translated from English into isiXhosa. The aim of the study is to scrutinise some of the strategies used by the translators in their translations. Preliminary results reveal that translators from English into isiXhosa may explicitate or implicitate the translation using various strategies like addition, infusing target language culture, translating source language idiom by another figure of speech or even omitting some words. This may have minimal or significant impact on the transferred message.
- Full Text:
- Date Issued: 2021
- Authors: Madolo, Yolisa
- Date: 2021
- Subjects: Children Xhosa Grammar, Comparative and general--Ideophone Children, Black, in literature Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7010 , vital:52637 , xlink:href="https://doi.org/10.1080/02572117.2021.2010919"
- Description: Translation scholars suggest various strategies for dealing with equivalence and non-equivalence. These popular strategies address non-equivalence, the converse of equivalence, that is commonly found in translation. Nonequivalence is found at word, phrase, sentence, and pragmatic levels. Not a great deal of research has been done in the translation strategies used between English and South African indigenous languages. It is possible that these languages employ some strategies that are not listed under current, popular strategies. These strategies may be necessitated by the linguistic and historical differences between English and African languages. For instance, what is acceptable in question form in English might be more suitable as a statement in African languages, specifically isiXhosa. The strategies to be presented are from an ongoing study of selected children’s stories translated from English into isiXhosa. The aim of the study is to scrutinise some of the strategies used by the translators in their translations. Preliminary results reveal that translators from English into isiXhosa may explicitate or implicitate the translation using various strategies like addition, infusing target language culture, translating source language idiom by another figure of speech or even omitting some words. This may have minimal or significant impact on the transferred message.
- Full Text:
- Date Issued: 2021
Strengthening Environment and Sustainability Subject Knowledge Curriculum Challenges and Opportunities
- Schudel, Ingrid J, Lotz-Sisitka, Heila
- Authors: Schudel, Ingrid J , Lotz-Sisitka, Heila
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/435045 , vital:73126 , ISBN 9781928502241 , https://library.oapen.org/handle/20.500.12657/64082
- Description: This chapter serves as a positioning paper for the chapters that follow in which different environment and sustainability knowledge foci will be explored in the South African Curriculum Assessment Policy Statements (CAPS). As a series of interconnected and cross-cutting complexities, environment and sustainability content knowledge has relevance for, and is widely distributed across, different phases and subjects in the school curriculum (see discussion of environmental content knowledge in Schudel and Lotz-Sisitka, Chapter 1; Lotz-Sisitka et al., Chapter 6; Msezane, Chapter 7). Knowledge that makes its way into education curricula and teaching is produced within the wider scientific context. Bernstein (2000), in his theory of the pedagogical device, refers to this as the ‘Field of Production’. A significant knowledge-producing community for sustainability concerns is the global change research community (international and national)(South Africa DST 2010). Examining their research outputs and discourses can provide important insights for the development of knowledge in what Bernstein names ‘regions’, where singular disciplines such as Science (eg climate sciences/biodiversity sciences/water sciences/health sciences), come together with other singular disciplines such as education. Bernstein suggests that a first level of knowledge recontextualisation in the Field of Production occurs in these regions (eg where environmental educators or science educators recontextualise the knowledge of scientists).
- Full Text:
- Date Issued: 2021
- Authors: Schudel, Ingrid J , Lotz-Sisitka, Heila
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/435045 , vital:73126 , ISBN 9781928502241 , https://library.oapen.org/handle/20.500.12657/64082
- Description: This chapter serves as a positioning paper for the chapters that follow in which different environment and sustainability knowledge foci will be explored in the South African Curriculum Assessment Policy Statements (CAPS). As a series of interconnected and cross-cutting complexities, environment and sustainability content knowledge has relevance for, and is widely distributed across, different phases and subjects in the school curriculum (see discussion of environmental content knowledge in Schudel and Lotz-Sisitka, Chapter 1; Lotz-Sisitka et al., Chapter 6; Msezane, Chapter 7). Knowledge that makes its way into education curricula and teaching is produced within the wider scientific context. Bernstein (2000), in his theory of the pedagogical device, refers to this as the ‘Field of Production’. A significant knowledge-producing community for sustainability concerns is the global change research community (international and national)(South Africa DST 2010). Examining their research outputs and discourses can provide important insights for the development of knowledge in what Bernstein names ‘regions’, where singular disciplines such as Science (eg climate sciences/biodiversity sciences/water sciences/health sciences), come together with other singular disciplines such as education. Bernstein suggests that a first level of knowledge recontextualisation in the Field of Production occurs in these regions (eg where environmental educators or science educators recontextualise the knowledge of scientists).
- Full Text:
- Date Issued: 2021
Supporting Student Teachers to Teach Catchment and River Management in Geography
- Authors: Heath, Gavin , O’Donoghue, R
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/435167 , vital:73135 , ISBN 9781928502241 , https://library.oapen.org/handle/20.500.12657/64082
- Description: The inclusion of new environmental knowledge in the South African Geography Curriculum and Assessment Policy Statement (CAPS) has meant that many student teachers are unprepared to teach a systemic process like catchment and river management, which concerns the management of water catchment basins and the rivers within. New environ-mental knowledge, by definition, involves systems thinking towards a grasp of social-ecological systems, notably cause and effect processes, and circularity within a system. A so-cial-ecological system is the complex relationship between the social and ecological processes on a parcel of land. The need for such systems thinking is implicit in the catchment and river management component of the CAPS (South Africa DBE 2011). The teaching of a case study of a catchment management system (which is the management system that governs a water catchment basin) has never been included in any previous curriculum. Water management has devel-oped on a widening scale into the 21st century in South Afri-ca, but there was little comprehensive data on catchment management systems until 2017. It was only in July 2017 that a draft catchment management strategy was published. Hence it is not surprising that no curriculum case studies ex-ist since there was no data to base them on (Meissner et al. 2017). An internet search in June 2020 uncovered no trace of any catchment management strategy for the more densely populated and, arguably, more significant eastern catch-ments of the country.
- Full Text:
- Date Issued: 2021
- Authors: Heath, Gavin , O’Donoghue, R
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/435167 , vital:73135 , ISBN 9781928502241 , https://library.oapen.org/handle/20.500.12657/64082
- Description: The inclusion of new environmental knowledge in the South African Geography Curriculum and Assessment Policy Statement (CAPS) has meant that many student teachers are unprepared to teach a systemic process like catchment and river management, which concerns the management of water catchment basins and the rivers within. New environ-mental knowledge, by definition, involves systems thinking towards a grasp of social-ecological systems, notably cause and effect processes, and circularity within a system. A so-cial-ecological system is the complex relationship between the social and ecological processes on a parcel of land. The need for such systems thinking is implicit in the catchment and river management component of the CAPS (South Africa DBE 2011). The teaching of a case study of a catchment management system (which is the management system that governs a water catchment basin) has never been included in any previous curriculum. Water management has devel-oped on a widening scale into the 21st century in South Afri-ca, but there was little comprehensive data on catchment management systems until 2017. It was only in July 2017 that a draft catchment management strategy was published. Hence it is not surprising that no curriculum case studies ex-ist since there was no data to base them on (Meissner et al. 2017). An internet search in June 2020 uncovered no trace of any catchment management strategy for the more densely populated and, arguably, more significant eastern catch-ments of the country.
- Full Text:
- Date Issued: 2021
Sustainable Human Resource Practices for Organizational Competitiveness Post the Covid-19 Pandemic
- Asoba, Samson Nambei, Patricia, Nteboheng Mefi
- Authors: Asoba, Samson Nambei , Patricia, Nteboheng Mefi
- Date: 2021
- Subjects: Personel Management Covid-19 (Disease) Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/8118 , vital:61396 , xlink:href="https://www.abacademies.org/articles/Sustainable-human-resource-practices-for-organizational-competitiveness-post-the-covid-19-1528-2686-27-2-480.pdf"
- Description: The study was formulated to tap into the future of HRM given the disruptions arising from the Covid-119 pandemic as well as the progression of the global technological environment to the fourth industrial revolution. The aim of the study was to: the Covid-19 induced HRM practices underpinning future organizational competitiveness. A literature review strategy was adopted to achieve the study objective. The study established seven emerging themes to inform HRM practices for the competitiveness of organizations in future following the Covid-19 disturbances. These themes are: primacy of HRM, increased cyber influences, digitalization, remote HRM, human-machine interface skills, human-organisation strategic links as well as human-technology interface competencies. Based on the study findings, the study recommended HRM departments to move to HR 4.0 through the adoption of industry 4.0 technologies, increased automation, and digitalization as well as strengthen virtualization systems.
- Full Text:
- Date Issued: 2021
- Authors: Asoba, Samson Nambei , Patricia, Nteboheng Mefi
- Date: 2021
- Subjects: Personel Management Covid-19 (Disease) Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/8118 , vital:61396 , xlink:href="https://www.abacademies.org/articles/Sustainable-human-resource-practices-for-organizational-competitiveness-post-the-covid-19-1528-2686-27-2-480.pdf"
- Description: The study was formulated to tap into the future of HRM given the disruptions arising from the Covid-119 pandemic as well as the progression of the global technological environment to the fourth industrial revolution. The aim of the study was to: the Covid-19 induced HRM practices underpinning future organizational competitiveness. A literature review strategy was adopted to achieve the study objective. The study established seven emerging themes to inform HRM practices for the competitiveness of organizations in future following the Covid-19 disturbances. These themes are: primacy of HRM, increased cyber influences, digitalization, remote HRM, human-machine interface skills, human-organisation strategic links as well as human-technology interface competencies. Based on the study findings, the study recommended HRM departments to move to HR 4.0 through the adoption of industry 4.0 technologies, increased automation, and digitalization as well as strengthen virtualization systems.
- Full Text:
- Date Issued: 2021
Synthesis and emerging frontiers in social-ecological systems research methods
- Schluter, Maja, Biggs, Reinette, Clements, Hayley, de Vos, Alta, Maciejewski, Kristine, Preiser, Rika
- Authors: Schluter, Maja , Biggs, Reinette , Clements, Hayley , de Vos, Alta , Maciejewski, Kristine , Preiser, Rika
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/433887 , vital:73007 , ISBN 9781000401516 , https://library.oapen.org/handle/20.500.12657/49560
- Description: Social-ecological systems (SES) research is a rapidly emerging new research domain within the broader emerging area of sustainability science. It is largely a problem-driven and action-oriented field, motivated by the immense sustainability and equity-related challenges facing society (see Chapter 1). Social-ecological systems research is based on an understanding that SES are complex adaptive systems (CAS), where social and ecological dynamics are deeply intertwined, and give rise to features and problems that cannot be understood or addressed by studying these dimensions in isolation (see Chapter 2). The field draws on and combines methods from both natural and social sciences, and combines quantitative and qualitative approaches. As such, SES research is characterised by epistemological and methodological pluralism, which is challenging for those entering the field and has complex implications for the research process, methods and ethical considerations to be taken into account in SES research (see Chapter 3). This book aims to clarify and synthesise this plurality by providing an introduction to SES research (Part 1), and the diversity of methods currently used in the field (Part 2). The aim of this final chapter (Part 3) is to provide a synthesis of the current landscape of SES methods, critically reflect on the methods with respect to their ability to address systemic features of SES and discuss some of the most common methodological challenges associated with the complex adaptive and intertwined nature of SES. Based on this synthesis, we identify methodological gaps and discuss novel methods and method combinations that may help to address these gaps and move the field forward.
- Full Text:
- Date Issued: 2021
- Authors: Schluter, Maja , Biggs, Reinette , Clements, Hayley , de Vos, Alta , Maciejewski, Kristine , Preiser, Rika
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/433887 , vital:73007 , ISBN 9781000401516 , https://library.oapen.org/handle/20.500.12657/49560
- Description: Social-ecological systems (SES) research is a rapidly emerging new research domain within the broader emerging area of sustainability science. It is largely a problem-driven and action-oriented field, motivated by the immense sustainability and equity-related challenges facing society (see Chapter 1). Social-ecological systems research is based on an understanding that SES are complex adaptive systems (CAS), where social and ecological dynamics are deeply intertwined, and give rise to features and problems that cannot be understood or addressed by studying these dimensions in isolation (see Chapter 2). The field draws on and combines methods from both natural and social sciences, and combines quantitative and qualitative approaches. As such, SES research is characterised by epistemological and methodological pluralism, which is challenging for those entering the field and has complex implications for the research process, methods and ethical considerations to be taken into account in SES research (see Chapter 3). This book aims to clarify and synthesise this plurality by providing an introduction to SES research (Part 1), and the diversity of methods currently used in the field (Part 2). The aim of this final chapter (Part 3) is to provide a synthesis of the current landscape of SES methods, critically reflect on the methods with respect to their ability to address systemic features of SES and discuss some of the most common methodological challenges associated with the complex adaptive and intertwined nature of SES. Based on this synthesis, we identify methodological gaps and discuss novel methods and method combinations that may help to address these gaps and move the field forward.
- Full Text:
- Date Issued: 2021
Synthesis of a near infrared-actuated phthalocyanine-lipid vesicle system for augmented photodynamic therapy
- Nwahara, Namdi, Managa, Muthumuni, Stoffels, Mihlali, Britton, Jonathan, Prinsloo, Earl, Nyokong, Tebello
- Authors: Nwahara, Namdi , Managa, Muthumuni , Stoffels, Mihlali , Britton, Jonathan , Prinsloo, Earl , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185395 , vital:44383 , xlink:href="https://doi.org/10.1016/j.synthmet.2021.116811"
- Description: The efficacy of photodynamic therapy (PDT) is often limited by the poor bio-distributive properties of conventional photosensitizers and the local hypoxic microenvironment that characterises most solid tumours. Herein, a novel in situ oxygenic lipid formulation for photodynamic therapy (PDT) is reported. Such a hybrid was synthesized by adsorbing bimetallic nanozyme, MnO2@PtNPs (NPs = nanoparticles) onto graphene quantum dots (GQDs) – zinc (II) phthalocyanine conjugates, followed by liposomal encapsulation, affording it enhanced water solubility. The MnO2@PtNPs, which are is shown to possess excellent catalase-like properties surpassing that of MnO2 or PtNPs alone, serves to catalyze H2O2 to O2, while the zinc (II) phthalocyanine (1) serves to transform the formed oxygen to generate cytotoxic singlet oxygen immediately. We show that by combining each function of the respective building blocks, the as-synthesized 1-GQDs-MnO2@PtNPs-liposomes not only maintains the properties of oxygen supplementation through H2O2 catalysis but also displays cooperative properties for enhanced singlet oxygen production. Consequently, a remarkably improved PDT efficacy was observed for 1-GQDs-MnO2@PtNPs-liposomes in both normoxia and hypoxia. These results demonstrate the potential applicability of such nanozyme constituted 1-GQDs-MnO2@PtNPs-liposomes for achieving tumour treatment in hypoxic conditions by PDT.
- Full Text:
- Date Issued: 2021
- Authors: Nwahara, Namdi , Managa, Muthumuni , Stoffels, Mihlali , Britton, Jonathan , Prinsloo, Earl , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185395 , vital:44383 , xlink:href="https://doi.org/10.1016/j.synthmet.2021.116811"
- Description: The efficacy of photodynamic therapy (PDT) is often limited by the poor bio-distributive properties of conventional photosensitizers and the local hypoxic microenvironment that characterises most solid tumours. Herein, a novel in situ oxygenic lipid formulation for photodynamic therapy (PDT) is reported. Such a hybrid was synthesized by adsorbing bimetallic nanozyme, MnO2@PtNPs (NPs = nanoparticles) onto graphene quantum dots (GQDs) – zinc (II) phthalocyanine conjugates, followed by liposomal encapsulation, affording it enhanced water solubility. The MnO2@PtNPs, which are is shown to possess excellent catalase-like properties surpassing that of MnO2 or PtNPs alone, serves to catalyze H2O2 to O2, while the zinc (II) phthalocyanine (1) serves to transform the formed oxygen to generate cytotoxic singlet oxygen immediately. We show that by combining each function of the respective building blocks, the as-synthesized 1-GQDs-MnO2@PtNPs-liposomes not only maintains the properties of oxygen supplementation through H2O2 catalysis but also displays cooperative properties for enhanced singlet oxygen production. Consequently, a remarkably improved PDT efficacy was observed for 1-GQDs-MnO2@PtNPs-liposomes in both normoxia and hypoxia. These results demonstrate the potential applicability of such nanozyme constituted 1-GQDs-MnO2@PtNPs-liposomes for achieving tumour treatment in hypoxic conditions by PDT.
- Full Text:
- Date Issued: 2021
Synthesis, spectroscopic and nonlinear optical properties of asymmetric A3B type phthalocyanine complexes
- Authors: Mugeza, Rhulani Donney
- Date: 2021
- Subjects: Spectrum analysis , Mass spectrometry , Phthalocyanines
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/171667 , vital:42108
- Description: This work reports on the synthesis of symmetrical and asymmetrical A 3 B type metal free, cobalt and zinc Phthalocyanines (Pc) .A wide range of spectroscopic techniques such as Uv - visible absorption (UV), magnetic circular dichroism (MCD), mass spectrometry, elemental analysis, IR spectroscopy and time correlated single photo n counting spectroscopy (TCSPC) have been used to study the spectroscopic properties of the phthalocyanine complexes. The Z - scan technique was used to comparatively investigate the nonlinear absorption coefficient ( 휷 ) and the nonlinear refraction index ( 풏 ퟐ ) of the synthesized complexes. The following trend was obtained for the synthesized Pc’s in terms of the 휷 values 7.25 × 10 − 10 ( 4b ) > 3.76 × 10 − 10 ( 4a ) > 3.52 × 10 − 10 ( 4c ) > 2.29 × 10 − 10 ( 3c ) > 1.68 × 10 − 10 ( 3a ) > 1.65 × 10 − 10 ( 3b ) mW - 1 . The 휷 values trend of synthesized Pc complexes show that the asymmetrical A 3 B type metal free, cobalt and zinc Pc complexes ( 4a , 4b and 4c ) have larger 휷 values as compared to the octa - substituted symmetrical metal free, cobalt and zinc Pc complexes ( 3a , 3b and 3c ) which is attributed to the low symmetry of the Pc complexes. The five - level model rate equations were used to determine the two photon absorption, excited state absorption and ground state absorption cross sections of the synthesized complexes. The z inc A 3 B type asymmetrical Pc complexes gave the largest two photon absorption and 휎 푒 / 휎 푔 ratio values. This Pc complex could be used in future work to enhance the nonlinear response further by introducing nanomaterials and converting the Pc complex to a binuclear Pc. This work also reports on the density functional theory (DFT) calculations o f dipolar/octupolar contributions in order to study the first order hyperpolarizability of the synthesized Pc complexes.
- Full Text:
- Date Issued: 2021
- Authors: Mugeza, Rhulani Donney
- Date: 2021
- Subjects: Spectrum analysis , Mass spectrometry , Phthalocyanines
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/171667 , vital:42108
- Description: This work reports on the synthesis of symmetrical and asymmetrical A 3 B type metal free, cobalt and zinc Phthalocyanines (Pc) .A wide range of spectroscopic techniques such as Uv - visible absorption (UV), magnetic circular dichroism (MCD), mass spectrometry, elemental analysis, IR spectroscopy and time correlated single photo n counting spectroscopy (TCSPC) have been used to study the spectroscopic properties of the phthalocyanine complexes. The Z - scan technique was used to comparatively investigate the nonlinear absorption coefficient ( 휷 ) and the nonlinear refraction index ( 풏 ퟐ ) of the synthesized complexes. The following trend was obtained for the synthesized Pc’s in terms of the 휷 values 7.25 × 10 − 10 ( 4b ) > 3.76 × 10 − 10 ( 4a ) > 3.52 × 10 − 10 ( 4c ) > 2.29 × 10 − 10 ( 3c ) > 1.68 × 10 − 10 ( 3a ) > 1.65 × 10 − 10 ( 3b ) mW - 1 . The 휷 values trend of synthesized Pc complexes show that the asymmetrical A 3 B type metal free, cobalt and zinc Pc complexes ( 4a , 4b and 4c ) have larger 휷 values as compared to the octa - substituted symmetrical metal free, cobalt and zinc Pc complexes ( 3a , 3b and 3c ) which is attributed to the low symmetry of the Pc complexes. The five - level model rate equations were used to determine the two photon absorption, excited state absorption and ground state absorption cross sections of the synthesized complexes. The z inc A 3 B type asymmetrical Pc complexes gave the largest two photon absorption and 휎 푒 / 휎 푔 ratio values. This Pc complex could be used in future work to enhance the nonlinear response further by introducing nanomaterials and converting the Pc complex to a binuclear Pc. This work also reports on the density functional theory (DFT) calculations o f dipolar/octupolar contributions in order to study the first order hyperpolarizability of the synthesized Pc complexes.
- Full Text:
- Date Issued: 2021
Synthesis, theoretical calculations and laser flash photolysis studies of selected amphiphilic porphyrin derivatives used as biofilm photodegradative materials
- Openda, Yolande I, Ngoy, Bokolombe P, Muva, Jules T, Nyokong, Tebello
- Authors: Openda, Yolande I , Ngoy, Bokolombe P , Muva, Jules T , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190589 , vital:45008 , xlink:href="https://doi.org/10.1039/D1NJ02651H"
- Description: Photodynamic antimicrobial activities of gallium and indium porphyrins as well as their quaternized derivatives have been investigated against S. aureus and E. coli biofilms, as well as on their planktonic (free floating) cells using a light emitting diode lamp at 415 nm. The studied photosensitizers show considerable ability to generate singlet oxygen and the quaternized molecules 2a and 3a are potential photodynamic antimicrobial chemotherapy (PACT) agents with log10 colony forming units >9 for E. coli and S. aureus planktonic cells. The quaternized derivatives are found to have higher ability to significantly suppress the biofilms of both S. aureus and E. coli in vitro. Therefore, this demonstrates that they are potentially suitable photosensitive agents for PACT use. The TD-B3LYP/LanL2DZ calculations were performed to evaluate the singlet excitation energies of quaternized and non-quaternized porphyrins in vacuo. Our study shows excellent agreement between time-dependent density-functional theory (TD-DFT) excited energies and experimental S1 > S0 excitation energies. The small deviation observed between the calculated and experimental spectra arises from the solvent effect. The excitation energies observed in these UV-visible spectra mostly originated from electron promotion between the highest occupied molecular orbital (HOMO) for the less intense band and the HOMO−1 for the most intense band of the ground states to the lower unoccupied molecular orbital (LUMO) of the excited states.
- Full Text:
- Date Issued: 2021
- Authors: Openda, Yolande I , Ngoy, Bokolombe P , Muva, Jules T , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190589 , vital:45008 , xlink:href="https://doi.org/10.1039/D1NJ02651H"
- Description: Photodynamic antimicrobial activities of gallium and indium porphyrins as well as their quaternized derivatives have been investigated against S. aureus and E. coli biofilms, as well as on their planktonic (free floating) cells using a light emitting diode lamp at 415 nm. The studied photosensitizers show considerable ability to generate singlet oxygen and the quaternized molecules 2a and 3a are potential photodynamic antimicrobial chemotherapy (PACT) agents with log10 colony forming units >9 for E. coli and S. aureus planktonic cells. The quaternized derivatives are found to have higher ability to significantly suppress the biofilms of both S. aureus and E. coli in vitro. Therefore, this demonstrates that they are potentially suitable photosensitive agents for PACT use. The TD-B3LYP/LanL2DZ calculations were performed to evaluate the singlet excitation energies of quaternized and non-quaternized porphyrins in vacuo. Our study shows excellent agreement between time-dependent density-functional theory (TD-DFT) excited energies and experimental S1 > S0 excitation energies. The small deviation observed between the calculated and experimental spectra arises from the solvent effect. The excitation energies observed in these UV-visible spectra mostly originated from electron promotion between the highest occupied molecular orbital (HOMO) for the less intense band and the HOMO−1 for the most intense band of the ground states to the lower unoccupied molecular orbital (LUMO) of the excited states.
- Full Text:
- Date Issued: 2021
T Kondo (Ed) law and investment in Africa: the fovernance of foreign direct investment in Zimbabwe
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Investments, Foreign -- Africa, Sub-Saharan , Zimbabwe -- Economic conditions , Corporate governance
- Language: English
- Type: text , review , article
- Identifier: http://hdl.handle.net/11260/6387 , vital:45443 , xlink:href="http://dx.doi.org/10.17159/2077-4907/2021/ldd.v25.16 "
- Description: Tinashe Kondo’s book, Law and investment in Africa, narrates the efforts of a country to regain the trust [and the love] of foreign investors after several decades of argument and hostility. Encapsulated in the “Zimbabwe is open for business” slogan, these efforts show “how a country can move to regain credibility and commit to global rules despite its recent history”. This review of Kondo’s book concerns the manner in which readers can take advantage of this immensely useful publication. Particularly, this review looks into the book in order to advise law academics on possible strategies to integrate the book into their curricula in Zimbabwe and elsewhere on the continent.
- Full Text:
- Date Issued: 2021
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Investments, Foreign -- Africa, Sub-Saharan , Zimbabwe -- Economic conditions , Corporate governance
- Language: English
- Type: text , review , article
- Identifier: http://hdl.handle.net/11260/6387 , vital:45443 , xlink:href="http://dx.doi.org/10.17159/2077-4907/2021/ldd.v25.16 "
- Description: Tinashe Kondo’s book, Law and investment in Africa, narrates the efforts of a country to regain the trust [and the love] of foreign investors after several decades of argument and hostility. Encapsulated in the “Zimbabwe is open for business” slogan, these efforts show “how a country can move to regain credibility and commit to global rules despite its recent history”. This review of Kondo’s book concerns the manner in which readers can take advantage of this immensely useful publication. Particularly, this review looks into the book in order to advise law academics on possible strategies to integrate the book into their curricula in Zimbabwe and elsewhere on the continent.
- Full Text:
- Date Issued: 2021
Teacher Contexts as Amplifiers and Filters to Environmental Pedagogical Content Knowledge within a Professional Development System
- Brundit, Susan, Schudel, Ingrid J
- Authors: Brundit, Susan , Schudel, Ingrid J
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/435141 , vital:73133 , ISBN 9781928502241 , https://library.oapen.org/handle/20.500.12657/64082
- Description: The chapter draws on the contextual work underpinning a broader study that aimed to understand how environmental pedagogical content knowledge is supported and constructed in the Fundisa for Change teacher professional development (TPD) courses (Brundrit 2018). Necessary to this was an understanding of the contextual realities (amplifiers and filters) of the system in which the course occurs, leading to the question: How do school and classroom contexts act to amplify and filter the environmental pedagogical content knowledge learning of teachers in a teacher professional development programme?.
- Full Text:
- Date Issued: 2021
- Authors: Brundit, Susan , Schudel, Ingrid J
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/435141 , vital:73133 , ISBN 9781928502241 , https://library.oapen.org/handle/20.500.12657/64082
- Description: The chapter draws on the contextual work underpinning a broader study that aimed to understand how environmental pedagogical content knowledge is supported and constructed in the Fundisa for Change teacher professional development (TPD) courses (Brundrit 2018). Necessary to this was an understanding of the contextual realities (amplifiers and filters) of the system in which the course occurs, leading to the question: How do school and classroom contexts act to amplify and filter the environmental pedagogical content knowledge learning of teachers in a teacher professional development programme?.
- Full Text:
- Date Issued: 2021
Teacher Professional Development in Environment and Sustainability Education
- Songqwaru, Zintle, Tshiningayamwe, Sirkka
- Authors: Songqwaru, Zintle , Tshiningayamwe, Sirkka
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/435248 , vital:73142 , ISBN 9781928502241 , https://library.oapen.org/handle/20.500.12657/64082
- Description: No education policy, no matter how well designed, can succeed without a teacher (Sanyal 2013). Additionally, a change in policy alone is not sufficient to improve an education system (Livingstone 2012), no matter how well meaning. The quality of teachers’ professional practices determines to some extent the quality of teaching and learning in the schooling sector. Teacher quality, and not only teacher supply, is important for learning; hence, teacher professional development should be a priority in all education and development strategies (Unesco 2015a).
- Full Text:
- Date Issued: 2021
- Authors: Songqwaru, Zintle , Tshiningayamwe, Sirkka
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/435248 , vital:73142 , ISBN 9781928502241 , https://library.oapen.org/handle/20.500.12657/64082
- Description: No education policy, no matter how well designed, can succeed without a teacher (Sanyal 2013). Additionally, a change in policy alone is not sufficient to improve an education system (Livingstone 2012), no matter how well meaning. The quality of teachers’ professional practices determines to some extent the quality of teaching and learning in the schooling sector. Teacher quality, and not only teacher supply, is important for learning; hence, teacher professional development should be a priority in all education and development strategies (Unesco 2015a).
- Full Text:
- Date Issued: 2021
Teaching and learning for change: Education and sustainability in South Africa
- Schudel, Ingrid J, Songqwaru, Zintle, Tshiningayamwe, Sirkka, Lotz-Sisitka, Heila
- Authors: Schudel, Ingrid J , Songqwaru, Zintle , Tshiningayamwe, Sirkka , Lotz-Sisitka, Heila
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/434971 , vital:73120 , ISBN 9781928502241 , https://library.oapen.org/handle/20.500.12657/64082
- Description: Like many national curricula around the world, South Africa’s curriculum is rich in environment and sustainability content. Despite this, environmental teaching and learning can be challenging for educators. This comes at a time when Sustainable Development Goal 4 via Target 4.7 requires governments to integrate Education for Sustainable Development into national education systems. Teaching and Learning for Change is an exploration of how teachers and teacher educators engage environment and sustainability content knowledge, methods, and assessment practices – an exposition of quality education processes in support of ecological and social justice and sustainability. The chapters evolve from a ten-year research programme led out of the DSI/NRF SARChI Chair in Global Change and Social Learning Systems working with national partners in the Fundisa for Change programme and the UNESCO Sustainability Starts with Teachers programme. They show the integration of education for sustainable development in teacher professional development and curricula in schools in South Africa. They reveal how university-based researchers, teachers and teacher educators have made theoretically and contextually reasoned choices about their lives and their teaching in response to calls for a more sustainable world in which education must play a role. Teaching and Learning for Change will be of interest to education policymakers in government, advisors and educators in educational and environmental departments, NGOs and other institutions. It will also be of interest to teacher educators, teachers and researchers in education more generally, and environment and sustainability education specifically.
- Full Text:
- Date Issued: 2021
- Authors: Schudel, Ingrid J , Songqwaru, Zintle , Tshiningayamwe, Sirkka , Lotz-Sisitka, Heila
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/434971 , vital:73120 , ISBN 9781928502241 , https://library.oapen.org/handle/20.500.12657/64082
- Description: Like many national curricula around the world, South Africa’s curriculum is rich in environment and sustainability content. Despite this, environmental teaching and learning can be challenging for educators. This comes at a time when Sustainable Development Goal 4 via Target 4.7 requires governments to integrate Education for Sustainable Development into national education systems. Teaching and Learning for Change is an exploration of how teachers and teacher educators engage environment and sustainability content knowledge, methods, and assessment practices – an exposition of quality education processes in support of ecological and social justice and sustainability. The chapters evolve from a ten-year research programme led out of the DSI/NRF SARChI Chair in Global Change and Social Learning Systems working with national partners in the Fundisa for Change programme and the UNESCO Sustainability Starts with Teachers programme. They show the integration of education for sustainable development in teacher professional development and curricula in schools in South Africa. They reveal how university-based researchers, teachers and teacher educators have made theoretically and contextually reasoned choices about their lives and their teaching in response to calls for a more sustainable world in which education must play a role. Teaching and Learning for Change will be of interest to education policymakers in government, advisors and educators in educational and environmental departments, NGOs and other institutions. It will also be of interest to teacher educators, teachers and researchers in education more generally, and environment and sustainability education specifically.
- Full Text:
- Date Issued: 2021
Terminaliamide, a new ceramide and other phytoconstituents from the roots of Terminalia mantaly H. Perrier and their biological activities
- Mbosso, Emmanuel, Siwe-Noundou, Xavier, Fannang, Simon, Song, Achille M, Assob, Jules C N, Hoppe, Heinrich, Krause, Rui W M
- Authors: Mbosso, Emmanuel , Siwe-Noundou, Xavier , Fannang, Simon , Song, Achille M , Assob, Jules C N , Hoppe, Heinrich , Krause, Rui W M
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/191779 , vital:45163 , xlink:href="https://doi.org/10.1080/14786419.2019.1647425"
- Description: Terminaliamide (1), a new ceramide was isolated from the roots of Terminalia mantaly H. Perrier (Combretaceae) along with 4 known compounds (2–5). The structures of the compounds were elucidated using 1D and 2D NMR spectroscopy analysis and mass spectrometry. Compound 1 exhibited moderated antibacterial activity towards Staphylococcus aureus with MIC value of 62.5 μg/mL. The crude MeOH extract (TMr) highly reduced Plasmodium falciparum growth with an IC50 value of 10.11 μg/mL, while hexane fraction (F1) highly reduced Trypanosoma brucei brucei growth with an IC50 value of 5.60 µg/mL. All tested samples presented little or no in vitro cytotoxicity on HeLa cell line. The present work confirms that T. mantaly is medicinally important and may be used effectively as an antimicrobial, an antiplasmodial and an antitrypanosomial with promising therapeutic index.
- Full Text:
- Date Issued: 2021
- Authors: Mbosso, Emmanuel , Siwe-Noundou, Xavier , Fannang, Simon , Song, Achille M , Assob, Jules C N , Hoppe, Heinrich , Krause, Rui W M
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/191779 , vital:45163 , xlink:href="https://doi.org/10.1080/14786419.2019.1647425"
- Description: Terminaliamide (1), a new ceramide was isolated from the roots of Terminalia mantaly H. Perrier (Combretaceae) along with 4 known compounds (2–5). The structures of the compounds were elucidated using 1D and 2D NMR spectroscopy analysis and mass spectrometry. Compound 1 exhibited moderated antibacterial activity towards Staphylococcus aureus with MIC value of 62.5 μg/mL. The crude MeOH extract (TMr) highly reduced Plasmodium falciparum growth with an IC50 value of 10.11 μg/mL, while hexane fraction (F1) highly reduced Trypanosoma brucei brucei growth with an IC50 value of 5.60 µg/mL. All tested samples presented little or no in vitro cytotoxicity on HeLa cell line. The present work confirms that T. mantaly is medicinally important and may be used effectively as an antimicrobial, an antiplasmodial and an antitrypanosomial with promising therapeutic index.
- Full Text:
- Date Issued: 2021
The antibacterial and antifungal properties of neutral, octacationic and hexadecacationic Zn phthalocyanines when conjugated to silver nanoparticles
- Mapukata, Sibusisiwe, Sen, Pinar, Osifeko, Olawale L, Nyokong, Tebello
- Authors: Mapukata, Sibusisiwe , Sen, Pinar , Osifeko, Olawale L , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185667 , vital:44408 , xlink:href="https://doi.org/10.1016/j.pdpdt.2021.102361"
- Description: The syntheses and characterization of novel octacationic and hexadecacationic Pcs is reported. With the aim of enhancing singlet oxygen generation efficiencies and hence antimicrobial activities, these Pcs (including their neutral counterpart) are conjugated to Ag nanoparticles (AgNPs). The obtained results show that the conjugate composed of the neutral Pc has a higher loading of Pcs as well as a greater singlet oxygen quantum yield enhancement (in the presence of AgNPs) in DMSO. The antimicrobial efficiencies of the Pcs and their conjugates were evaluated and compared on S. aureus, E. coli and C. albicans. The cationic Pcs possess better activity than the neutral Pc against all the microorganisms with the hexadecacationic Pc being the best. This work therefore demonstrates that increase in the number of cationic charges on the reported Pcs results in enhanced antimicrobial activities, which is maintained even when conjugated to Ag nanoparticles. The high activity and lack of selectivity of the cationic Pcs when conjugated to Ag NPs against different microorganisms make them good candidates for real life antimicrobial treatments.
- Full Text:
- Date Issued: 2021
- Authors: Mapukata, Sibusisiwe , Sen, Pinar , Osifeko, Olawale L , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185667 , vital:44408 , xlink:href="https://doi.org/10.1016/j.pdpdt.2021.102361"
- Description: The syntheses and characterization of novel octacationic and hexadecacationic Pcs is reported. With the aim of enhancing singlet oxygen generation efficiencies and hence antimicrobial activities, these Pcs (including their neutral counterpart) are conjugated to Ag nanoparticles (AgNPs). The obtained results show that the conjugate composed of the neutral Pc has a higher loading of Pcs as well as a greater singlet oxygen quantum yield enhancement (in the presence of AgNPs) in DMSO. The antimicrobial efficiencies of the Pcs and their conjugates were evaluated and compared on S. aureus, E. coli and C. albicans. The cationic Pcs possess better activity than the neutral Pc against all the microorganisms with the hexadecacationic Pc being the best. This work therefore demonstrates that increase in the number of cationic charges on the reported Pcs results in enhanced antimicrobial activities, which is maintained even when conjugated to Ag nanoparticles. The high activity and lack of selectivity of the cationic Pcs when conjugated to Ag NPs against different microorganisms make them good candidates for real life antimicrobial treatments.
- Full Text:
- Date Issued: 2021
The antibody assisted detection of HER2 on a cobalt porphyrin binuclear framework and gold functionalized graphene quantum dots modified electrode
- Centane, Sixole, Nyokong, Tebello
- Authors: Centane, Sixole , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185931 , vital:44449 , xlink:href="https://doi.org/10.1016/j.jelechem.2020.114908"
- Description: In this work a novel simple, inexpensive and highly sensitive approach for the antibody assisted detection of the human epidermal growth factor receptor 2 (HER2) is presented. Three sensors using carboxylic group containing gold functionalized graphene quantum dots (SNGQDs@AuNPs), CoP-BNF (cobalt porphyrin binuclear framework) and CoP-BNF/SNGQDs@AuNPs (the conjugate) nanocomposites on a GCE were designed. The sensors were fabricated by covalent immobilization of the antibody to the GCE via an amide bond. The modified GCE was characterized using cyclic voltammetry and impedance spectroscopy. The performance of the sensors was assessed using electrochemical impedance spectroscopy. The selective recognition of the antibody towards HER2 on the electrode led to an increase of the electron transfer resistance (Rct). The different modified electrodes had low detection limit values: 0.0327 ng/mL, 0.0454 ng/mL and 0.1072 ng/mL towards the detection of HER2. The sensors showed good stability and reproducibility. The sensors showed promising potential in clinical applicability, in the detection of HER2 protein in human serum.
- Full Text:
- Date Issued: 2021
- Authors: Centane, Sixole , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185931 , vital:44449 , xlink:href="https://doi.org/10.1016/j.jelechem.2020.114908"
- Description: In this work a novel simple, inexpensive and highly sensitive approach for the antibody assisted detection of the human epidermal growth factor receptor 2 (HER2) is presented. Three sensors using carboxylic group containing gold functionalized graphene quantum dots (SNGQDs@AuNPs), CoP-BNF (cobalt porphyrin binuclear framework) and CoP-BNF/SNGQDs@AuNPs (the conjugate) nanocomposites on a GCE were designed. The sensors were fabricated by covalent immobilization of the antibody to the GCE via an amide bond. The modified GCE was characterized using cyclic voltammetry and impedance spectroscopy. The performance of the sensors was assessed using electrochemical impedance spectroscopy. The selective recognition of the antibody towards HER2 on the electrode led to an increase of the electron transfer resistance (Rct). The different modified electrodes had low detection limit values: 0.0327 ng/mL, 0.0454 ng/mL and 0.1072 ng/mL towards the detection of HER2. The sensors showed good stability and reproducibility. The sensors showed promising potential in clinical applicability, in the detection of HER2 protein in human serum.
- Full Text:
- Date Issued: 2021