Electrocatalytic Activity of Asymmetrical Cobalt Phthalocyanines in the Presence of N Doped Graphene Quantum Dots: The Push-pull Effects of Substituents
- Nkhahle, Reitumetse, Sekhosana, Kutloano E, Centane, Sixolile, Nyokong, Tebello
- Authors: Nkhahle, Reitumetse , Sekhosana, Kutloano E , Centane, Sixolile , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186904 , vital:44546 , xlink:href="https://doi.org/10.1002/elan.201800837"
- Description: A series of Co phthalocyanine (CoPc) derivatives and their respective nitrogen doped graphene quantum dot conjugates were used as catalysts towards the electrooxidation of hydrazine. Using a glassy carbon electrode as a support for the electrocatalysts, through cyclic voltammetry and chronoamperometry, the effects of combining the CoPcs with the nitrogen doped graphene quantum dots (NGQDs) were studied. The general observations made were that the NGQDs improve the catalytic activity of the CoPcs in both the p-p stacked and covalently linked conjugates by increasing the sensitivities and lowering the limits of detection with values as low as 0.43 mM being recorded.
- Full Text:
- Authors: Nkhahle, Reitumetse , Sekhosana, Kutloano E , Centane, Sixolile , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186904 , vital:44546 , xlink:href="https://doi.org/10.1002/elan.201800837"
- Description: A series of Co phthalocyanine (CoPc) derivatives and their respective nitrogen doped graphene quantum dot conjugates were used as catalysts towards the electrooxidation of hydrazine. Using a glassy carbon electrode as a support for the electrocatalysts, through cyclic voltammetry and chronoamperometry, the effects of combining the CoPcs with the nitrogen doped graphene quantum dots (NGQDs) were studied. The general observations made were that the NGQDs improve the catalytic activity of the CoPcs in both the p-p stacked and covalently linked conjugates by increasing the sensitivities and lowering the limits of detection with values as low as 0.43 mM being recorded.
- Full Text:
Electrocatalytic activity of ethynylbenzyl phthalocyanines when linked to quantum dots via click chemistry: Towards efficient oxygen reduction reaction and H2O2 oxidation
- Mpeta, Lekhetho S, Nyokong, Tebello
- Authors: Mpeta, Lekhetho S , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187037 , vital:44558 , xlink:href="https://doi.org/10.1016/j.jelechem.2019.03.064"
- Description: This work describes the conjugation of Co, Mn and Fe tetra ethynyl benzyl phthalocyanines to CdTe/ZnS quantum dots via click chemistry. The synthesized conjugates were then immobilised on glassy carbon electrode and their electrocatalytic activity towards hydrogen peroxide oxidation and oxygen reduction investigated. CoPc (1)-QDs showed superior electrocatalytic behaviour towards hydrogen peroxide catalysis with sensitivity of 2.8 × 105 μA/mM and limit of detection of 0.023 μM. On the other hand, FePc(3)-QDs showed the best oxygen reduction activity involving a direct 4-electron mechanism.
- Full Text:
- Authors: Mpeta, Lekhetho S , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187037 , vital:44558 , xlink:href="https://doi.org/10.1016/j.jelechem.2019.03.064"
- Description: This work describes the conjugation of Co, Mn and Fe tetra ethynyl benzyl phthalocyanines to CdTe/ZnS quantum dots via click chemistry. The synthesized conjugates were then immobilised on glassy carbon electrode and their electrocatalytic activity towards hydrogen peroxide oxidation and oxygen reduction investigated. CoPc (1)-QDs showed superior electrocatalytic behaviour towards hydrogen peroxide catalysis with sensitivity of 2.8 × 105 μA/mM and limit of detection of 0.023 μM. On the other hand, FePc(3)-QDs showed the best oxygen reduction activity involving a direct 4-electron mechanism.
- Full Text:
Empire in Lusaka: hip-hop, young men and masculinity in an African city
- Authors: Mulolani, Happy
- Date: 2019
- Subjects: Empire (Television program : 2015) -- Influence , Hip-hop -- Zambia -- Lusaka , Young men -- Zambia -- Lusaka , Young men -- Psychology -- Zambia -- Lusaka , Young men -- Social conditions -- Zambia -- Lusaka , Rap musicians -- Zambia -- Lusaka , Masculinity -- Zambia -- Lusaka
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/92650 , vital:30736
- Description: This study examines young Zambian men who are aspiring hip hop artists in Lusaka and the meanings they make of the representations of masculinity in Empire, a popular US television drama. Broadcast locally via satellite on the South African cable network, DStv, Empire narrates the story of a family of powerful men as they battle for the control of Empire, a successful hip-hop label. Of significance is how the programme’s representations of masculinity resonate with the young men’s own ideas of masculinity within a highly patriarchal and conservative urban African space. The young male hip-hop artists encounter their everyday experiences in a context of a range of socio-economic challenges within the urban space of Lusaka which presents them with very limited economic opportunities and resources. Underpinned by a constructivist approach, this reception study explores how these young male artists encounter their everyday experiences in the city and how its structural constraints are navigated through hip-hop, a highly popular local cultural form. The male artists’ reactions to the programme are dependent on their socio-economic location and the types of skills and resources they draw on in order to traverse their everyday experience of city life which concurrently is perceived as exclusionary and as impacting on their livelihoods and aspirations.
- Full Text:
- Authors: Mulolani, Happy
- Date: 2019
- Subjects: Empire (Television program : 2015) -- Influence , Hip-hop -- Zambia -- Lusaka , Young men -- Zambia -- Lusaka , Young men -- Psychology -- Zambia -- Lusaka , Young men -- Social conditions -- Zambia -- Lusaka , Rap musicians -- Zambia -- Lusaka , Masculinity -- Zambia -- Lusaka
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/92650 , vital:30736
- Description: This study examines young Zambian men who are aspiring hip hop artists in Lusaka and the meanings they make of the representations of masculinity in Empire, a popular US television drama. Broadcast locally via satellite on the South African cable network, DStv, Empire narrates the story of a family of powerful men as they battle for the control of Empire, a successful hip-hop label. Of significance is how the programme’s representations of masculinity resonate with the young men’s own ideas of masculinity within a highly patriarchal and conservative urban African space. The young male hip-hop artists encounter their everyday experiences in a context of a range of socio-economic challenges within the urban space of Lusaka which presents them with very limited economic opportunities and resources. Underpinned by a constructivist approach, this reception study explores how these young male artists encounter their everyday experiences in the city and how its structural constraints are navigated through hip-hop, a highly popular local cultural form. The male artists’ reactions to the programme are dependent on their socio-economic location and the types of skills and resources they draw on in order to traverse their everyday experience of city life which concurrently is perceived as exclusionary and as impacting on their livelihoods and aspirations.
- Full Text:
Employing the Processing Capability of Mixing Consoles and Audio Interfaces to Spatialize Sound:
- Authors: Foss, Richard
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426758 , vital:72389 , https://www.aes.org/e-lib/browse.cfm?elib=22211
- Description: Many audio interfaces and all mixing consoles have signal mixing capabilities. This paper describes an immersive sound system that employs these capabilities in order to spatialise sound sources, where these sources could be any of the inputs to these mix-capable devices. Graphic spatialisation control is provided on client devices, and 3D coordinates are sent to a server. The server uses these coordinates and speaker positions to render mix level and reverb parameter values. These values are sent to the mixer device using a control protocol. Advantages of this approach are that all inputs can be spatialised, and low-level processing is offloaded from the computer.
- Full Text:
- Authors: Foss, Richard
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426758 , vital:72389 , https://www.aes.org/e-lib/browse.cfm?elib=22211
- Description: Many audio interfaces and all mixing consoles have signal mixing capabilities. This paper describes an immersive sound system that employs these capabilities in order to spatialise sound sources, where these sources could be any of the inputs to these mix-capable devices. Graphic spatialisation control is provided on client devices, and 3D coordinates are sent to a server. The server uses these coordinates and speaker positions to render mix level and reverb parameter values. These values are sent to the mixer device using a control protocol. Advantages of this approach are that all inputs can be spatialised, and low-level processing is offloaded from the computer.
- Full Text:
Encapsulation of isoniazid-conjugated phthalocyanine-In-cyclodextrin-in-liposomes using heating method
- Nkanga, Christian I, Krause, Rui W M
- Authors: Nkanga, Christian I , Krause, Rui W M
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193999 , vital:45414 , xlink:href="https://doi.org/10.1038/s41598-019-47991-y"
- Description: Liposomes are reputed colloidal vehicles that hold the promise for targeted delivery of anti-tubercular drugs (ATBDs) to alveolar macrophages that host Mycobacterium tuberculosis. However, the costly status of liposome technology, particularly due to the use of special manufacture equipment and expensive lipid materials, may preclude wider developments of therapeutic liposomes. In this study, we report efficient encapsulation of a complex system, consisting of isoniazid-hydrazone-phthalocyanine conjugate (Pc-INH) in gamma-cyclodextrin (γ-CD), in liposomes using crude soybean lecithin by means of a simple organic solvent-free method, heating method (HM). Inclusion complexation was performed in solution and solid-state, and evaluated using UV-Vis, magnetic circular dichroism, 1H NMR, diffusion ordered spectroscopy and FT-IR. The HM-liposomes afforded good encapsulation efficiency (71%) for such a large Pc-INH/γ-CD complex (PCD) system. The stability and properties of the PCD-HM-liposomes look encouraging; with particle size 240 nm and Zeta potential −57 mV that remained unchanged upon storage at 4 °C for 5 weeks. The release study performed in different pH media revealed controlled release profiles that went up to 100% at pH 4.4, from about 40% at pH 7.4. This makes PCD-liposomes a promising system for site-specific ATBD delivery, and a good example of simple liposomal encapsulation of large hydrophobic compounds.
- Full Text:
- Authors: Nkanga, Christian I , Krause, Rui W M
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193999 , vital:45414 , xlink:href="https://doi.org/10.1038/s41598-019-47991-y"
- Description: Liposomes are reputed colloidal vehicles that hold the promise for targeted delivery of anti-tubercular drugs (ATBDs) to alveolar macrophages that host Mycobacterium tuberculosis. However, the costly status of liposome technology, particularly due to the use of special manufacture equipment and expensive lipid materials, may preclude wider developments of therapeutic liposomes. In this study, we report efficient encapsulation of a complex system, consisting of isoniazid-hydrazone-phthalocyanine conjugate (Pc-INH) in gamma-cyclodextrin (γ-CD), in liposomes using crude soybean lecithin by means of a simple organic solvent-free method, heating method (HM). Inclusion complexation was performed in solution and solid-state, and evaluated using UV-Vis, magnetic circular dichroism, 1H NMR, diffusion ordered spectroscopy and FT-IR. The HM-liposomes afforded good encapsulation efficiency (71%) for such a large Pc-INH/γ-CD complex (PCD) system. The stability and properties of the PCD-HM-liposomes look encouraging; with particle size 240 nm and Zeta potential −57 mV that remained unchanged upon storage at 4 °C for 5 weeks. The release study performed in different pH media revealed controlled release profiles that went up to 100% at pH 4.4, from about 40% at pH 7.4. This makes PCD-liposomes a promising system for site-specific ATBD delivery, and a good example of simple liposomal encapsulation of large hydrophobic compounds.
- Full Text:
Engagement in local social-ecological knowledge practices in a seasonal cycles approach for transitioning to future sustainability
- Authors: O'Donoghue, Rob
- 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:
- Authors: O'Donoghue, Rob
- 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:
Enumeration, conformation sampling and population of libraries of peptide macrocycles for the search of chemotherapeutic cardioprotection agents
- Authors: Sigauke, Lester Takunda
- Date: 2019
- Subjects: Peptides -- Synthesis , Macrocyclic compounds , Drug development , Drug discovery , Cardiovascular system -- Diseases -- Prevention , Proteins -- Synthesis
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/116056 , vital:34293
- Description: Peptides are uniquely endowed with features that allow them to perturb previously difficult to drug biomolecular targets. Peptide macrocycles in particular have seen a flurry of recent interest due to their enhanced bioavailability, tunability and specificity. Although these properties make them attractive hit-candidates in early stage drug discovery, knowing which peptides to pursue is non‐trivial due to the magnitude of the peptide sequence space. Computational screening approaches show promise in their ability to address the size of this search space but suffer from their inability to accurately interrogate the conformational landscape of peptide macrocycles. We developed an in‐silico compound enumerator that was tasked with populating a conformationally laden peptide virtual library. This library was then used in the search for cardio‐protective agents (that may be administered, reducing tissue damage during reperfusion after ischemia (heart attacks)). Our enumerator successfully generated a library of 15.2 billion compounds, requiring the use of compression algorithms, conformational sampling protocols and management of aggregated compute resources in the context of a local cluster. In the absence of experimental biophysical data, we performed biased sampling during alchemical molecular dynamics simulations in order to observe cyclophilin‐D perturbation by cyclosporine A and its mitochondrial targeted analogue. Reliable intermediate state averaging through a WHAM analysis of the biased dynamic pulling simulations confirmed that the cardio‐protective activity of cyclosporine A was due to its mitochondrial targeting. Paralleltempered solution molecular dynamics in combination with efficient clustering isolated the essential dynamics of a cyclic peptide scaffold. The rapid enumeration of skeletons from these essential dynamics gave rise to a conformation laden virtual library of all the 15.2 Billion unique cyclic peptides (given the limits on peptide sequence imposed). Analysis of this library showed the exact extent of physicochemical properties covered, relative to the bare scaffold precursor. Molecular docking of a subset of the virtual library against cyclophilin‐D showed significant improvements in affinity to the target (relative to cyclosporine A). The conformation laden virtual library, accessed by our methodology, provided derivatives that were able to make many interactions per peptide with the cyclophilin‐D target. Machine learning methods showed promise in the training of Support Vector Machines for synthetic feasibility prediction for this library. The synergy between enumeration and conformational sampling greatly improves the performance of this library during virtual screening, even when only a subset is used.
- Full Text:
- Authors: Sigauke, Lester Takunda
- Date: 2019
- Subjects: Peptides -- Synthesis , Macrocyclic compounds , Drug development , Drug discovery , Cardiovascular system -- Diseases -- Prevention , Proteins -- Synthesis
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/116056 , vital:34293
- Description: Peptides are uniquely endowed with features that allow them to perturb previously difficult to drug biomolecular targets. Peptide macrocycles in particular have seen a flurry of recent interest due to their enhanced bioavailability, tunability and specificity. Although these properties make them attractive hit-candidates in early stage drug discovery, knowing which peptides to pursue is non‐trivial due to the magnitude of the peptide sequence space. Computational screening approaches show promise in their ability to address the size of this search space but suffer from their inability to accurately interrogate the conformational landscape of peptide macrocycles. We developed an in‐silico compound enumerator that was tasked with populating a conformationally laden peptide virtual library. This library was then used in the search for cardio‐protective agents (that may be administered, reducing tissue damage during reperfusion after ischemia (heart attacks)). Our enumerator successfully generated a library of 15.2 billion compounds, requiring the use of compression algorithms, conformational sampling protocols and management of aggregated compute resources in the context of a local cluster. In the absence of experimental biophysical data, we performed biased sampling during alchemical molecular dynamics simulations in order to observe cyclophilin‐D perturbation by cyclosporine A and its mitochondrial targeted analogue. Reliable intermediate state averaging through a WHAM analysis of the biased dynamic pulling simulations confirmed that the cardio‐protective activity of cyclosporine A was due to its mitochondrial targeting. Paralleltempered solution molecular dynamics in combination with efficient clustering isolated the essential dynamics of a cyclic peptide scaffold. The rapid enumeration of skeletons from these essential dynamics gave rise to a conformation laden virtual library of all the 15.2 Billion unique cyclic peptides (given the limits on peptide sequence imposed). Analysis of this library showed the exact extent of physicochemical properties covered, relative to the bare scaffold precursor. Molecular docking of a subset of the virtual library against cyclophilin‐D showed significant improvements in affinity to the target (relative to cyclosporine A). The conformation laden virtual library, accessed by our methodology, provided derivatives that were able to make many interactions per peptide with the cyclophilin‐D target. Machine learning methods showed promise in the training of Support Vector Machines for synthetic feasibility prediction for this library. The synergy between enumeration and conformational sampling greatly improves the performance of this library during virtual screening, even when only a subset is used.
- Full Text:
Environmental drivers of the composition and distribution of larval fish assemblages off the south coast of South Africa
- Authors: Trassierra, Jaqueline Anne
- Date: 2019
- Subjects: Fishes -- Larvae -- South Africa -- Eastern Cape , Fishes -- Larvae -- Migration -- South Africa -- Eastern Cape , Fishes -- Larvae -- Dispersal -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/68154 , vital:29207
- Description: The species composition, distribution and patterns of vertical migration of larval fish assemblages were investigated in March and in September 2013 within two adjacent log spiral bays, Algoa Bay and St Francis Bay, on the south coast of South Africa. Fish larvae were collected by means of a boat towed bongo net (57 cm diameter; mesh aperture 500 μm). An onshore (2 km) and an offshore (3 km) station were each sampled twice during the daytime (06:00 – 18:00) with two horizontal tows: near the surface (0.5 m) and close to the bottom (12 m). Tows were repeated at night (18:00 – 23:00) for onshore sites. Larval catches included 16 fish families and 40 species. A multivariate analysis indicated that the species composition was significantly different between Algoa Bay and St Francis Bay, with Engraulidae, Blenniidae, Sparidae, Soleidae and Cynoglossidae making important contributions to the larval fish catch in Algoa Bay, while Blenniidae, Engraulidae, Tripterygiidae, Sparidae and Gobiesocidae contributed significantly in St Francis Bay. Differences in assemblage composition were noted between the Spring (September–October) and Autumn (March-April) months. The species composition of larval fish assemblages was related to wind speed, wave height, cloud cover, sea water temperature, depth, average current speed and direction. Wind speed, wave height, temperature and depth significantly contributed to the variation in larval fish densities. Abundances of larval fishes were greater offshore than onshore, larvae from pelagic eggs dominated catches offshore, while larvae from demersal eggs dominated onshore catches. Habitat structure strongly influenced the composition of larval fishes between the bays and abundances were significantly greater at night than during the day. Most larval fishes displayed a reverse diel vertical migration pattern and were most influenced by predators, wind speed and cloud cover. This study shows that larval fish assemblages are highly complex and patchy. Spawning mode, individual species behaviour, diel vertical migration, current structure, depth, temperature, wind speed, cloud cover and type of habitat substratum all influence larval fish composition and distribution in the nearshore waters of South Africa.
- Full Text:
- Authors: Trassierra, Jaqueline Anne
- Date: 2019
- Subjects: Fishes -- Larvae -- South Africa -- Eastern Cape , Fishes -- Larvae -- Migration -- South Africa -- Eastern Cape , Fishes -- Larvae -- Dispersal -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/68154 , vital:29207
- Description: The species composition, distribution and patterns of vertical migration of larval fish assemblages were investigated in March and in September 2013 within two adjacent log spiral bays, Algoa Bay and St Francis Bay, on the south coast of South Africa. Fish larvae were collected by means of a boat towed bongo net (57 cm diameter; mesh aperture 500 μm). An onshore (2 km) and an offshore (3 km) station were each sampled twice during the daytime (06:00 – 18:00) with two horizontal tows: near the surface (0.5 m) and close to the bottom (12 m). Tows were repeated at night (18:00 – 23:00) for onshore sites. Larval catches included 16 fish families and 40 species. A multivariate analysis indicated that the species composition was significantly different between Algoa Bay and St Francis Bay, with Engraulidae, Blenniidae, Sparidae, Soleidae and Cynoglossidae making important contributions to the larval fish catch in Algoa Bay, while Blenniidae, Engraulidae, Tripterygiidae, Sparidae and Gobiesocidae contributed significantly in St Francis Bay. Differences in assemblage composition were noted between the Spring (September–October) and Autumn (March-April) months. The species composition of larval fish assemblages was related to wind speed, wave height, cloud cover, sea water temperature, depth, average current speed and direction. Wind speed, wave height, temperature and depth significantly contributed to the variation in larval fish densities. Abundances of larval fishes were greater offshore than onshore, larvae from pelagic eggs dominated catches offshore, while larvae from demersal eggs dominated onshore catches. Habitat structure strongly influenced the composition of larval fishes between the bays and abundances were significantly greater at night than during the day. Most larval fishes displayed a reverse diel vertical migration pattern and were most influenced by predators, wind speed and cloud cover. This study shows that larval fish assemblages are highly complex and patchy. Spawning mode, individual species behaviour, diel vertical migration, current structure, depth, temperature, wind speed, cloud cover and type of habitat substratum all influence larval fish composition and distribution in the nearshore waters of South Africa.
- Full Text:
Environmental niche patterns of native and non-native fishes within an invaded African river system
- Kadye, Wilbert T, Booth, Anthony J
- Authors: Kadye, Wilbert T , Booth, Anthony J
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124407 , vital:35605 , https://doi.10.1111/jfb.13988
- Description: To test ecological niche theory, this study investigated the spatial patterns and the environmental niches of native and non-native fishes within the invaded Great Fish River system, South Africa. For the native fishes, there were contrasting environmental niche breadths that varied from being small to being large and overlapped for most species, except minnows that were restricted to headwater tributaries. In addition, there was high niche overlap in habitat association among fishes with similar distribution. It was therefore inferred that habitat filtering-driven spatial organization was important in explaining native species distribution patterns. In comparison, most non-native fishes were found to have broad environmental niches and these fishes showed high tolerance to environmental conditions, which generally supported the niche opportunity hypothesis. The proliferation of multiple non-native fishes in the mainstem section suggest that they form a functional assemblage that is probably facilitated by the anthropogenic modification of flow regimes through inter-basin water transfer. Based on the distribution patterns observed in the study, it was inferred that there was a likelihood of negative interactions between native and nonnative fishes. Such effects are likely to be exacerbated by altered flow regime that was likely to have negative implications for native ichthyofauna.
- Full Text:
- Authors: Kadye, Wilbert T , Booth, Anthony J
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124407 , vital:35605 , https://doi.10.1111/jfb.13988
- Description: To test ecological niche theory, this study investigated the spatial patterns and the environmental niches of native and non-native fishes within the invaded Great Fish River system, South Africa. For the native fishes, there were contrasting environmental niche breadths that varied from being small to being large and overlapped for most species, except minnows that were restricted to headwater tributaries. In addition, there was high niche overlap in habitat association among fishes with similar distribution. It was therefore inferred that habitat filtering-driven spatial organization was important in explaining native species distribution patterns. In comparison, most non-native fishes were found to have broad environmental niches and these fishes showed high tolerance to environmental conditions, which generally supported the niche opportunity hypothesis. The proliferation of multiple non-native fishes in the mainstem section suggest that they form a functional assemblage that is probably facilitated by the anthropogenic modification of flow regimes through inter-basin water transfer. Based on the distribution patterns observed in the study, it was inferred that there was a likelihood of negative interactions between native and nonnative fishes. Such effects are likely to be exacerbated by altered flow regime that was likely to have negative implications for native ichthyofauna.
- Full Text:
Establishing computational approaches towards identifying malarial allosteric modulators: a case study of plasmodium falciparum hsp70s
- Amusengeri, Arnold, Astl, Lindy, Lobb, Kevin A, Verkhivker, Gennady M, Tastan Bishop, Özlem
- Authors: Amusengeri, Arnold , Astl, Lindy , Lobb, Kevin A , Verkhivker, Gennady M , Tastan Bishop, Özlem
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/163000 , vital:41003 , https://doi.org/10.3390/ijms20225574
- Description: Combating malaria is almost a never-ending battle, as Plasmodium parasites develop resistance to the drugs used against them, as observed recently in artemisinin-based combination therapies. The main concern now is if the resistant parasite strains spread from Southeast Asia to Africa, the continent hosting most malaria cases. To prevent catastrophic results, we need to find non-conventional approaches. Allosteric drug targeting sites and modulators might be a new hope for malarial treatments. Heat shock proteins (HSPs) are potential malarial drug targets and have complex allosteric control mechanisms. Yet, studies on designing allosteric modulators against them are limited. Here, we identified allosteric modulators (SANC190 and SANC651) against P. falciparum Hsp70-1 and Hsp70-x, affecting the conformational dynamics of the proteins, delicately balanced by the endogenous ligands. Previously, we established a pipeline to identify allosteric sites and modulators. This study also further investigated alternative approaches to speed up the process by comparing all atom molecular dynamics simulations and dynamic residue network analysis with the coarse-grained (CG) versions of the calculations. Betweenness centrality (BC) profiles for PfHsp70-1 and PfHsp70-x derived from CG simulations not only revealed similar trends but also pointed to the same functional regions and specific residues corresponding to BC profile peaks.
- Full Text:
- Authors: Amusengeri, Arnold , Astl, Lindy , Lobb, Kevin A , Verkhivker, Gennady M , Tastan Bishop, Özlem
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/163000 , vital:41003 , https://doi.org/10.3390/ijms20225574
- Description: Combating malaria is almost a never-ending battle, as Plasmodium parasites develop resistance to the drugs used against them, as observed recently in artemisinin-based combination therapies. The main concern now is if the resistant parasite strains spread from Southeast Asia to Africa, the continent hosting most malaria cases. To prevent catastrophic results, we need to find non-conventional approaches. Allosteric drug targeting sites and modulators might be a new hope for malarial treatments. Heat shock proteins (HSPs) are potential malarial drug targets and have complex allosteric control mechanisms. Yet, studies on designing allosteric modulators against them are limited. Here, we identified allosteric modulators (SANC190 and SANC651) against P. falciparum Hsp70-1 and Hsp70-x, affecting the conformational dynamics of the proteins, delicately balanced by the endogenous ligands. Previously, we established a pipeline to identify allosteric sites and modulators. This study also further investigated alternative approaches to speed up the process by comparing all atom molecular dynamics simulations and dynamic residue network analysis with the coarse-grained (CG) versions of the calculations. Betweenness centrality (BC) profiles for PfHsp70-1 and PfHsp70-x derived from CG simulations not only revealed similar trends but also pointed to the same functional regions and specific residues corresponding to BC profile peaks.
- Full Text:
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:
- 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:
Examination of teacher mediation and its impact on foundational reading skills in Grade-R classrooms in Namibia
- Authors: Nzwala, Kenneth
- Date: 2019
- Subjects: Reading (Elementary) -- Namibia -- Case studies , Elementary school teachers -- Namibia -- Case studies , Early childhood education -- Curricula -- Namibia , Vygotskiĭ, L. S. (Lev Semenovich), 1896-1934
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/92291 , vital:30700
- Description: Grounded in the Sociocultural Theory (SCT) of Lev Vygotsky, this study examined teacher mediation and its impact on development of foundational reading skills in six Grade-R classrooms in the Zambezi Region of Namibia. It was a multiple case study with a mixed methods approach. Six Grade R classes attached to primary schools were studied to facilitate following of the same learners to Grade One. A purposive sampling technique was used to draw a sample of six Grade-R and Grade-One teachers. Learners were selected using stratified random sampling. Data were collected by means of interviews, observation of Grade R lessons, and an emergent Early Grade Reading Assessment (eEGRA) test. eEGRA facilitated benchmarking teacher efficacy in mediating Grade R learners’ foundational reading skills. Nine Grade One learners per teacher per school took part in the test at the beginning of Grade One. Three 35-minute lessons, per Grade-R teacher, were observed. Data were analysed statistically using ANOVA with thematic qualitative analysis of interview data against document analysis of curricula, teacher planning and learner exercise books. The study established that teachers had no understanding of ‘emergent literacy’, did not promote a love of books, or promote learning through play. There was evidence of a language barrier during lessons, which potentially reduced the efficacy of teacher mediation. The curriculum was found to be inappropriate as it lacked guidance relevant to Grade R teachers. This point was particularly pertinent as all teachers in this study had not received Grade-R training and were therefore looking to the curriculum for support. The difference between what teachers said and what they did was revealed in their classroom practice. Lesson planning was found to be superficial and non-reflective, with a marked discrepancy between what was planned and what was done. The style of pedagogy was primarily transmissive and authoritarian. Finally, the socio-economic distribution of the schools did not demonstrate significant impact on learner performance in the benchmark test. This study concludes that the Grade-R curriculum needs to be revised to be culturally and age appropriate. Teachers should be trained to understand the speciality of Grade R, and support should be given to current teachers to adopt a child-centred, play-based approach to pedagogy.
- Full Text:
- Authors: Nzwala, Kenneth
- Date: 2019
- Subjects: Reading (Elementary) -- Namibia -- Case studies , Elementary school teachers -- Namibia -- Case studies , Early childhood education -- Curricula -- Namibia , Vygotskiĭ, L. S. (Lev Semenovich), 1896-1934
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/92291 , vital:30700
- Description: Grounded in the Sociocultural Theory (SCT) of Lev Vygotsky, this study examined teacher mediation and its impact on development of foundational reading skills in six Grade-R classrooms in the Zambezi Region of Namibia. It was a multiple case study with a mixed methods approach. Six Grade R classes attached to primary schools were studied to facilitate following of the same learners to Grade One. A purposive sampling technique was used to draw a sample of six Grade-R and Grade-One teachers. Learners were selected using stratified random sampling. Data were collected by means of interviews, observation of Grade R lessons, and an emergent Early Grade Reading Assessment (eEGRA) test. eEGRA facilitated benchmarking teacher efficacy in mediating Grade R learners’ foundational reading skills. Nine Grade One learners per teacher per school took part in the test at the beginning of Grade One. Three 35-minute lessons, per Grade-R teacher, were observed. Data were analysed statistically using ANOVA with thematic qualitative analysis of interview data against document analysis of curricula, teacher planning and learner exercise books. The study established that teachers had no understanding of ‘emergent literacy’, did not promote a love of books, or promote learning through play. There was evidence of a language barrier during lessons, which potentially reduced the efficacy of teacher mediation. The curriculum was found to be inappropriate as it lacked guidance relevant to Grade R teachers. This point was particularly pertinent as all teachers in this study had not received Grade-R training and were therefore looking to the curriculum for support. The difference between what teachers said and what they did was revealed in their classroom practice. Lesson planning was found to be superficial and non-reflective, with a marked discrepancy between what was planned and what was done. The style of pedagogy was primarily transmissive and authoritarian. Finally, the socio-economic distribution of the schools did not demonstrate significant impact on learner performance in the benchmark test. This study concludes that the Grade-R curriculum needs to be revised to be culturally and age appropriate. Teachers should be trained to understand the speciality of Grade R, and support should be given to current teachers to adopt a child-centred, play-based approach to pedagogy.
- Full Text:
Examining mathematical reasoning through enacted visualisation
- Authors: Dongwi, Beata Lididimikeni
- Date: 2019
- Subjects: Visualization , Mathematics -- Study and teaching -- Namibia , Mathematics -- Study and teaching -- Audio-visual aids , Geometry -- Study and teaching , Reasoning , Mathematical ability
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/68192 , vital:29217
- Description: This study sets out to analyse the co-emergence of visualisation and reasoning processes when selected learners engaged in solving word problems. The study argues that visualisation processes and mathematical reasoning processes are closely interlinked in the process of engaging in any mathematical activity. This qualitative research project adopted a case study methodology embedded within a broader interpretative orientation. The research participants were a cohort of 17 mixedgender and mixed-ability Grade 11 learners from a private school in southern Namibia. Data was collected in three phases and comprised of one-on-one task-based interviews in the first phase, focus group task-based interviews in the second, and semi-structured reflective interviews in the third. The analytical framework was informed by elements of enactivism and consisted of a hybrid of observable visualisation and mathematical reasoning indicators. The study was framed by an enactivist perspective that served as a linking mediator to bring visualisation and reasoning processes together, and as a lens through which the coemergence of these processes was observed and analysed. The key enactivist concepts of structural coupling and co-emergence were the two mediating ideas that enabled me to discuss the links between visualisation and reasoning that emerged whilst my participants solved the set word problems. The study argues that the visualisation processes enacted by the participants when solving these problems are inseparable from the reasoning processes that the participants brought to bear; that is, they co-emerged.
- Full Text:
- Authors: Dongwi, Beata Lididimikeni
- Date: 2019
- Subjects: Visualization , Mathematics -- Study and teaching -- Namibia , Mathematics -- Study and teaching -- Audio-visual aids , Geometry -- Study and teaching , Reasoning , Mathematical ability
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/68192 , vital:29217
- Description: This study sets out to analyse the co-emergence of visualisation and reasoning processes when selected learners engaged in solving word problems. The study argues that visualisation processes and mathematical reasoning processes are closely interlinked in the process of engaging in any mathematical activity. This qualitative research project adopted a case study methodology embedded within a broader interpretative orientation. The research participants were a cohort of 17 mixedgender and mixed-ability Grade 11 learners from a private school in southern Namibia. Data was collected in three phases and comprised of one-on-one task-based interviews in the first phase, focus group task-based interviews in the second, and semi-structured reflective interviews in the third. The analytical framework was informed by elements of enactivism and consisted of a hybrid of observable visualisation and mathematical reasoning indicators. The study was framed by an enactivist perspective that served as a linking mediator to bring visualisation and reasoning processes together, and as a lens through which the coemergence of these processes was observed and analysed. The key enactivist concepts of structural coupling and co-emergence were the two mediating ideas that enabled me to discuss the links between visualisation and reasoning that emerged whilst my participants solved the set word problems. The study argues that the visualisation processes enacted by the participants when solving these problems are inseparable from the reasoning processes that the participants brought to bear; that is, they co-emerged.
- Full Text:
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:
- 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:
Exhibition review: Site of memory: Berni Searle’s-aplace-in-the-sun
- Muvhuti, Barnabas, Zhang, Lifang
- Authors: Muvhuti, Barnabas , Zhang, Lifang
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/146937 , vital:38578 , https://artthrob.co.za/2019/07/31/site-of-memory-berni-searles-a-place-in-the-sun/
- Description: Commissioned by the National Arts Festival, Berni Searle created a four-screen multi-channel video installation, A Place in the Sun, which cooperated perfectly with the four wall compartments of the rotunda-shaped Gallery in the Round in the basement of the 1820 Settlers Monument. With the shifting of lights, the video symbolically indicates a full day at a drained swimming pool, from morning to sunset until the whole scene turns into ashes and darkness.
- Full Text:
- Authors: Muvhuti, Barnabas , Zhang, Lifang
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/146937 , vital:38578 , https://artthrob.co.za/2019/07/31/site-of-memory-berni-searles-a-place-in-the-sun/
- Description: Commissioned by the National Arts Festival, Berni Searle created a four-screen multi-channel video installation, A Place in the Sun, which cooperated perfectly with the four wall compartments of the rotunda-shaped Gallery in the Round in the basement of the 1820 Settlers Monument. With the shifting of lights, the video symbolically indicates a full day at a drained swimming pool, from morning to sunset until the whole scene turns into ashes and darkness.
- Full Text:
Expanding learning in clergy leadership formation in an Anglican Church Province in Southern Africa: a critical realist study
- Authors: Chinganga, Percy
- Date: 2019
- Subjects: Leadership -- Africa, Southern -- Religious aspects -- Christianity , Church management -- Africa, Southern , Critical realism , Educational leadership , Anglican Church of Southern Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/92258 , vital:30704
- Description: The focus of this study was to investigate the kind of learning that happened when participants involved in clergy leadership formation programmes and activities in the Anglican Church of Southern Africa (ACSA) engaged in their responsibilities as a collective. Further, the research sought to explore collaborative and transforming practices in ACSA clergy leadership formation programmes and activities which could be expanded through learning. The study is premised on an investigation of the historical foundations of Christian leadership formation processes which sought to establish clergy leadership formation models relevant to ACSA (the context of the study) from inception (1848) to date (2017). This entailed investigating how the developments which have happened in the church from its inception in the New Testament times through the Medieval and Reformation periods, have contributed to the emergence of distinct Christian leadership formation models which have formed the basis of clergy leadership formation in ACSA. Accordingly, the study highlighted key issues relating to clergy leadership formation which are discernible in the different historical phases of the life and work of the church with the objective of establishing how ACSA, through expansive learning, could transform her current clergy leadership formation model(s) towards collaborative and transforming practices. The concept of expansive learning, drawn from Cultural Historical Activity Theory (CHAT), was used in the study as a methodological tool to create an environment where research participants (formators) from several dioceses would engage in collective work activities which would surface contradictions relating to how clergy leadership formation programmes and activities were understood and facilitated in ACSA. In response to the surfaced contradictions, the study engaged research participants in Change Laboratory Workshops whose goal was to transform the organisation (ACSA) in two particular ways: empowerment of participants (formators) with conceptual tools relevant to their responsibilities in clergy leadership formation programmes and activities in ACSA, and improvement of organisational cultural practices, that is, the manner in which ACSA ought to conceptualise, design, plan, facilitate and manage clergy leadership formation programmes and activities. The latter brought into the discourse the need for participants (formators) to select and employ methodologies, methods, approaches and resources relevant to the southern African context where ACSA is located even though the study also acknowledged the influence of other Anglican Church contexts on what happened at the local level. In order to decipher meaning out of investigated phenomena about clergy leadership formation in ACSA, the study employed the critical realist “underlabouring” philosophy advanced by theorists such as Bhaskar to surface underlying mechanisms that exist at the level of the “real” in order to understand the causes of particular events and experiences as they manifest in the “actual” and “empirical” domains of the world, ACSA in the case of the study. In particular, the study engaged critically the opinion deliberated by critical realists concerning the interplay between structure and agency in relation to the responsibilities of the research participants (formators) in ACSA clergy leadership formation programmes and activities. For instance, the study had an interest in investigating why bishops (principal formators in ACSA) exercised their episcopal authority in the manner they do and why individual formators were concerned about particular issues which relate to the facilitation of clergy leadership formation in ACSA (agential reflexivity/subjectivity). The study observed that, in the case of diocesan bishops, critical realists would argue that, by virtue of the authority which comes with their responsibilities (agency), they have the power to influence transformation of practices in clergy leadership formation in ACSA at any given point in time. The flip side of the discourse was also taken note of: that some bishops, for reasons known to themselves and their predecessors, are often reluctant to embrace new ideas relating to clergy leadership formation practices in their dioceses. Further, through critical realist lens, the study concluded that Canons, Vision and Mission statements, Acts, and structures such as Synod of Bishops, Provincial Synod, ABoTE, Cott, and TfM structurally shape ACSA, thus providing the organisation with a stable ontology which ought to direct, regulate and control the manner in which clergy leadership formation programmes and activities were conceptualised, designed, planned, facilitated and managed. As such, the study had an interest in establishing what would happen, in relation to clergy leadership formation practices in ACSA, when these structures would have been activated? Beyond that, in view of the goal of the study, it was enquired how expansive learning processes could be helpful in responding to the research findings towards exploring collaborative and transforming clergy leadership formation practices in ACSA. Drawing from the conceptual framework which was carved in the study on the basis of the theoretical tools (critical realism and educational leadership theory) and methodological tools (CHAT orientated concepts) undergirded by the Vygotskian theorisation of human consciousness development, the study concluded that clergy leadership formation is a collaborative activity which calls for the recognition, appreciation and utilisation of available expertise in ACSA and provision of a platform where participants (formators) could engage collectively on issues relating to their work with the objective of building each other up in knowledge and skills (expansive learning) towards realisation of the goals and objectives of the organisation. Diverse understandings (contradictions) of what needed to be prioritised in the facilitation of clergy leadership formation in ACSA would be considered as a positive rather than a negative. Ultimately, through the use of inductive, abductive and retroductive modes of inference, the study modelled a transforming, transformational, transformative, embodied and incarnational model of clergy leadership formation which ACSA could consider using in future deliberations on the object of study particularly in relation to the key research findings across the case studies which were used in the study.
- Full Text:
- Authors: Chinganga, Percy
- Date: 2019
- Subjects: Leadership -- Africa, Southern -- Religious aspects -- Christianity , Church management -- Africa, Southern , Critical realism , Educational leadership , Anglican Church of Southern Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/92258 , vital:30704
- Description: The focus of this study was to investigate the kind of learning that happened when participants involved in clergy leadership formation programmes and activities in the Anglican Church of Southern Africa (ACSA) engaged in their responsibilities as a collective. Further, the research sought to explore collaborative and transforming practices in ACSA clergy leadership formation programmes and activities which could be expanded through learning. The study is premised on an investigation of the historical foundations of Christian leadership formation processes which sought to establish clergy leadership formation models relevant to ACSA (the context of the study) from inception (1848) to date (2017). This entailed investigating how the developments which have happened in the church from its inception in the New Testament times through the Medieval and Reformation periods, have contributed to the emergence of distinct Christian leadership formation models which have formed the basis of clergy leadership formation in ACSA. Accordingly, the study highlighted key issues relating to clergy leadership formation which are discernible in the different historical phases of the life and work of the church with the objective of establishing how ACSA, through expansive learning, could transform her current clergy leadership formation model(s) towards collaborative and transforming practices. The concept of expansive learning, drawn from Cultural Historical Activity Theory (CHAT), was used in the study as a methodological tool to create an environment where research participants (formators) from several dioceses would engage in collective work activities which would surface contradictions relating to how clergy leadership formation programmes and activities were understood and facilitated in ACSA. In response to the surfaced contradictions, the study engaged research participants in Change Laboratory Workshops whose goal was to transform the organisation (ACSA) in two particular ways: empowerment of participants (formators) with conceptual tools relevant to their responsibilities in clergy leadership formation programmes and activities in ACSA, and improvement of organisational cultural practices, that is, the manner in which ACSA ought to conceptualise, design, plan, facilitate and manage clergy leadership formation programmes and activities. The latter brought into the discourse the need for participants (formators) to select and employ methodologies, methods, approaches and resources relevant to the southern African context where ACSA is located even though the study also acknowledged the influence of other Anglican Church contexts on what happened at the local level. In order to decipher meaning out of investigated phenomena about clergy leadership formation in ACSA, the study employed the critical realist “underlabouring” philosophy advanced by theorists such as Bhaskar to surface underlying mechanisms that exist at the level of the “real” in order to understand the causes of particular events and experiences as they manifest in the “actual” and “empirical” domains of the world, ACSA in the case of the study. In particular, the study engaged critically the opinion deliberated by critical realists concerning the interplay between structure and agency in relation to the responsibilities of the research participants (formators) in ACSA clergy leadership formation programmes and activities. For instance, the study had an interest in investigating why bishops (principal formators in ACSA) exercised their episcopal authority in the manner they do and why individual formators were concerned about particular issues which relate to the facilitation of clergy leadership formation in ACSA (agential reflexivity/subjectivity). The study observed that, in the case of diocesan bishops, critical realists would argue that, by virtue of the authority which comes with their responsibilities (agency), they have the power to influence transformation of practices in clergy leadership formation in ACSA at any given point in time. The flip side of the discourse was also taken note of: that some bishops, for reasons known to themselves and their predecessors, are often reluctant to embrace new ideas relating to clergy leadership formation practices in their dioceses. Further, through critical realist lens, the study concluded that Canons, Vision and Mission statements, Acts, and structures such as Synod of Bishops, Provincial Synod, ABoTE, Cott, and TfM structurally shape ACSA, thus providing the organisation with a stable ontology which ought to direct, regulate and control the manner in which clergy leadership formation programmes and activities were conceptualised, designed, planned, facilitated and managed. As such, the study had an interest in establishing what would happen, in relation to clergy leadership formation practices in ACSA, when these structures would have been activated? Beyond that, in view of the goal of the study, it was enquired how expansive learning processes could be helpful in responding to the research findings towards exploring collaborative and transforming clergy leadership formation practices in ACSA. Drawing from the conceptual framework which was carved in the study on the basis of the theoretical tools (critical realism and educational leadership theory) and methodological tools (CHAT orientated concepts) undergirded by the Vygotskian theorisation of human consciousness development, the study concluded that clergy leadership formation is a collaborative activity which calls for the recognition, appreciation and utilisation of available expertise in ACSA and provision of a platform where participants (formators) could engage collectively on issues relating to their work with the objective of building each other up in knowledge and skills (expansive learning) towards realisation of the goals and objectives of the organisation. Diverse understandings (contradictions) of what needed to be prioritised in the facilitation of clergy leadership formation in ACSA would be considered as a positive rather than a negative. Ultimately, through the use of inductive, abductive and retroductive modes of inference, the study modelled a transforming, transformational, transformative, embodied and incarnational model of clergy leadership formation which ACSA could consider using in future deliberations on the object of study particularly in relation to the key research findings across the case studies which were used in the study.
- Full Text:
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:
- 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:
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.
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- 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.
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Exploration of challenges in bringing traditional medicine into SA’s healthcare system, using medicinal plants for treatment of waterborne diarrhoeal diseases as a case study
- Authors: Keche, Priscilla
- Date: 2019
- Subjects: Traditional medicine -- South Africa , Waterborne infection -- South Africa , Diarrhea -- South Africa , Healers -- South Africa , Medical care -- Quality control , Medicinal plants -- South Africa , Diarrhea in children -- South Africa , World Health Organization
- Language: English
- Type: thesis , text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/118035 , vital:34588
- Description: Thesis (MSc)--Rhodes University, Faculty of Science, Biotechnology Innovation Centre (RUBIC), 2019.
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- Authors: Keche, Priscilla
- Date: 2019
- Subjects: Traditional medicine -- South Africa , Waterborne infection -- South Africa , Diarrhea -- South Africa , Healers -- South Africa , Medical care -- Quality control , Medicinal plants -- South Africa , Diarrhea in children -- South Africa , World Health Organization
- Language: English
- Type: thesis , text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/118035 , vital:34588
- Description: Thesis (MSc)--Rhodes University, Faculty of Science, Biotechnology Innovation Centre (RUBIC), 2019.
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Exploring a shift in teacher practices after going through an intervention on the integration of local knowledge in grade 9 physical science lessons
- Authors: Mika, Rauha T
- Date: 2019
- Subjects: Physical sciences -- Study and teaching (Secondary) -- Namibia , Ethnoscience -- Study and teaching -- Namibia , Science -- Study and teaching (Secondary) -- Namibia , Curriculum planning -- Study and teaching -- Namibia
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/96801 , vital:31323
- Description: It has been advocated by many scholars that the integration of local or indigenous knowledge into science classrooms might make science more relevant and accessible to learners, particularly in culturally diverse classrooms. As a result, the Namibian Grade 9 Physical Science curriculum expects teachers to integrate learners’ local or indigenous knowledge in their science classrooms. Despite these ideals, there are no clear instructions on how to go about doing this. This is exacerbated in part by the poor or lack of continuing professional development for science teachers. It is against this background that this study sought to explore an intervention on the integration of local or indigenous knowledge in Grade 9 Physical Science lessons. The study is underpinned by an interpretive paradigm and is informed by Vygotsky’s socio-cultural theory and Wenger’s community of practice. Within the interpretive paradigm, a qualitative case study approach was employed. It was carried out in four schools with four Physical Science teachers from Otjiwarongo circuit in Namibia. Qualitative data were generated using workshop discussions, document analysis, semi-structured interviews, classroom observations and reflections. A variety of data generation techniques were used for triangulation and validity purposes. Data were subsequently analysed inductively to come up with themes. The findings of the study revealed that before the intervention the teachers involved in this study had little knowledge about the integration of local or indigenous knowledge in science lessons. However, after their voluntary participation in the intervention, they were enabled to develop and mediate model lessons that integrated local or indigenous knowledge in their classrooms which their learners subsequently found to be stimulating. The findings of the study further revealed that integrating local or indigenous knowledge in science lessons had the potential to promote active participation by learners and foster learning using easily accessible resources. The study thus recommends that teachers should, where possible, strive to integrate learners’ local or indigenous knowledge in science lessons.
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- Authors: Mika, Rauha T
- Date: 2019
- Subjects: Physical sciences -- Study and teaching (Secondary) -- Namibia , Ethnoscience -- Study and teaching -- Namibia , Science -- Study and teaching (Secondary) -- Namibia , Curriculum planning -- Study and teaching -- Namibia
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/96801 , vital:31323
- Description: It has been advocated by many scholars that the integration of local or indigenous knowledge into science classrooms might make science more relevant and accessible to learners, particularly in culturally diverse classrooms. As a result, the Namibian Grade 9 Physical Science curriculum expects teachers to integrate learners’ local or indigenous knowledge in their science classrooms. Despite these ideals, there are no clear instructions on how to go about doing this. This is exacerbated in part by the poor or lack of continuing professional development for science teachers. It is against this background that this study sought to explore an intervention on the integration of local or indigenous knowledge in Grade 9 Physical Science lessons. The study is underpinned by an interpretive paradigm and is informed by Vygotsky’s socio-cultural theory and Wenger’s community of practice. Within the interpretive paradigm, a qualitative case study approach was employed. It was carried out in four schools with four Physical Science teachers from Otjiwarongo circuit in Namibia. Qualitative data were generated using workshop discussions, document analysis, semi-structured interviews, classroom observations and reflections. A variety of data generation techniques were used for triangulation and validity purposes. Data were subsequently analysed inductively to come up with themes. The findings of the study revealed that before the intervention the teachers involved in this study had little knowledge about the integration of local or indigenous knowledge in science lessons. However, after their voluntary participation in the intervention, they were enabled to develop and mediate model lessons that integrated local or indigenous knowledge in their classrooms which their learners subsequently found to be stimulating. The findings of the study further revealed that integrating local or indigenous knowledge in science lessons had the potential to promote active participation by learners and foster learning using easily accessible resources. The study thus recommends that teachers should, where possible, strive to integrate learners’ local or indigenous knowledge in science lessons.
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