Thermoluminescence properties of potassium fluoride:
- Ogundare, F O, Folley, Damilola E, Chithambo, Makaiko L, Arise, T O
- Authors: Ogundare, F O , Folley, Damilola E , Chithambo, Makaiko L , Arise, T O
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/160500 , vital:40451 , https://doi.org/10.1016/j.nimb.2020.09.009
- Description: This study is designed to examine the thermoluminescence characteristics of potassium fluoride for possible use as a thermoluminescence dosemeter. Thermoluminescence measurements were carried out at doses up to 20 Gy and heating rates between 0.2 and 4°C/s. The glow curve of the fluoride, readout at 1°Cs−1, exhibited two peaks at 130 and 250 °C. In addition, two shoulder peaks appeared at 70 and 200°C.
- Full Text:
- Authors: Ogundare, F O , Folley, Damilola E , Chithambo, Makaiko L , Arise, T O
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/160500 , vital:40451 , https://doi.org/10.1016/j.nimb.2020.09.009
- Description: This study is designed to examine the thermoluminescence characteristics of potassium fluoride for possible use as a thermoluminescence dosemeter. Thermoluminescence measurements were carried out at doses up to 20 Gy and heating rates between 0.2 and 4°C/s. The glow curve of the fluoride, readout at 1°Cs−1, exhibited two peaks at 130 and 250 °C. In addition, two shoulder peaks appeared at 70 and 200°C.
- Full Text:
Think Piece. Working for Living: Popular Education as/at Work for Social-ecological Justice
- Burt, Jane C, James, Anna, Walters, Shirley, Von Kotze, Astrid
- Authors: Burt, Jane C , James, Anna , Walters, Shirley , Von Kotze, Astrid
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/388150 , vital:68310 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/165826"
- Description: Drawing on the working lives of popular educators who are striving for socioeconomic and socio-ecological justice, we demonstrate how popular education is a form of care work which is feminised, often undervalued and unrecognised as highly skilled work. It is relational work that aims to forge solidarity with communities and the environment. Given the state of the planet, the radical transformations that are needed, and the future projection of ‘work’ as including the care economy in large measure, we argue that popular education is a generative site for further exploration of research into work and learning. However, to move popular education as work from the margins means to rethink the current economic system of value. Addressing the contradiction that undervalues work for life/living, popular education engages transformative action motivated by a deep sense of solidarity and a focus on imagining alternatives as an act of hope.
- Full Text:
- Authors: Burt, Jane C , James, Anna , Walters, Shirley , Von Kotze, Astrid
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/388150 , vital:68310 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/165826"
- Description: Drawing on the working lives of popular educators who are striving for socioeconomic and socio-ecological justice, we demonstrate how popular education is a form of care work which is feminised, often undervalued and unrecognised as highly skilled work. It is relational work that aims to forge solidarity with communities and the environment. Given the state of the planet, the radical transformations that are needed, and the future projection of ‘work’ as including the care economy in large measure, we argue that popular education is a generative site for further exploration of research into work and learning. However, to move popular education as work from the margins means to rethink the current economic system of value. Addressing the contradiction that undervalues work for life/living, popular education engages transformative action motivated by a deep sense of solidarity and a focus on imagining alternatives as an act of hope.
- Full Text:
Think Piece: Learning, Living and Leading into Transgression–A reflection on decolonial praxis in a neoliberal world
- Kulundu-Bolus, Injairu M, McGarry, Dylan K, Lotz-Sisitka, Heila
- Authors: Kulundu-Bolus, Injairu M , McGarry, Dylan K , Lotz-Sisitka, Heila
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182406 , vital:43827 , xlink:href="10.4314/sajee.v36i1.14"
- Description: Three scholar activists from South Africa reflect on what it means to transgress the limits of a neoliberal world and its crisis times, particularly considering transgressions in the service of a decolonial future. The authors explore three questions: i) What kind of learning can help us transgress the status quo? ii) How do we extend this learning into a commitment to actively living in transgressive ways? iii) What does it mean to lead in ways that re-generate a transgressive ethic in a neoliberal world? In a dialogical conversation format, the authors outline nine different but interconnected perspectives on learning, living and leading into transgression, with the aim of concurrently revealing the multiple layers of work that a decolonial future depends on, while demonstrating the ambitions of a pluriversal decolonial future through their writing. The intertwined narrative is not conclusive, as the processes marked out in brief are experiences that still need to be fully practised in new relations in times to come within academia-in-society-and-the-world with human and more-than-human actors. However, they do offer a generative set of questions, concepts and metaphors to give courage to boundary-dwelling scholar activists attempting transgressive research. These reflections seek to regenerate the transgressive ‘decolonial gestures’ (decolonialfutures.net) that we can undertake in a neo-liberal world, as an important part of environment and sustainability education practices. It draws out what an embodied practice of transgressive learning can entail when we become discerning of hegemonic discourses that reproduce the status quo. We pay homage to those decolonial scholars in the field of environment and sustainability education as we traverse this terrain, recognising their imagination and the transgressive movement that has come before us, but importantly we seek to also open pathways for those yet to come.
- Full Text:
- Authors: Kulundu-Bolus, Injairu M , McGarry, Dylan K , Lotz-Sisitka, Heila
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182406 , vital:43827 , xlink:href="10.4314/sajee.v36i1.14"
- Description: Three scholar activists from South Africa reflect on what it means to transgress the limits of a neoliberal world and its crisis times, particularly considering transgressions in the service of a decolonial future. The authors explore three questions: i) What kind of learning can help us transgress the status quo? ii) How do we extend this learning into a commitment to actively living in transgressive ways? iii) What does it mean to lead in ways that re-generate a transgressive ethic in a neoliberal world? In a dialogical conversation format, the authors outline nine different but interconnected perspectives on learning, living and leading into transgression, with the aim of concurrently revealing the multiple layers of work that a decolonial future depends on, while demonstrating the ambitions of a pluriversal decolonial future through their writing. The intertwined narrative is not conclusive, as the processes marked out in brief are experiences that still need to be fully practised in new relations in times to come within academia-in-society-and-the-world with human and more-than-human actors. However, they do offer a generative set of questions, concepts and metaphors to give courage to boundary-dwelling scholar activists attempting transgressive research. These reflections seek to regenerate the transgressive ‘decolonial gestures’ (decolonialfutures.net) that we can undertake in a neo-liberal world, as an important part of environment and sustainability education practices. It draws out what an embodied practice of transgressive learning can entail when we become discerning of hegemonic discourses that reproduce the status quo. We pay homage to those decolonial scholars in the field of environment and sustainability education as we traverse this terrain, recognising their imagination and the transgressive movement that has come before us, but importantly we seek to also open pathways for those yet to come.
- Full Text:
Thintitha, Celiwe
- Masombuka, Thobekile Hlobisile
- Authors: Masombuka, Thobekile Hlobisile
- Date: 2020
- Subjects: South African fiction (English) -- 21st century
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/147470 , vital:38639
- Description: This document consists of two (2) parts: Part A: Thesis (Creative Work) Part B: Portfolio
- Full Text:
- Authors: Masombuka, Thobekile Hlobisile
- Date: 2020
- Subjects: South African fiction (English) -- 21st century
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/147470 , vital:38639
- Description: This document consists of two (2) parts: Part A: Thesis (Creative Work) Part B: Portfolio
- Full Text:
Topsoil transfer from natural renosterveld to degraded old fields facilitates native vegetation recovery:
- Authors: Ruwanza, Sheunesu
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148639 , vital:38758 , https://doi.org/10.3390/su12093833
- Description: The transfer of soils from intact vegetation communities to degraded ecosystems is seen as a promising restoration tool aimed at facilitating vegetation recovery. This study examined how topsoil transfer from intact renosterveld to degraded old fields improves vegetation diversity, cover, and composition. Transferred topsoil were overlaid on 30 quadrats, each measuring 1 m2, in May 2009. Eight years following the initial soil transfer, vegetation diversity in the soil transfer site showed an increase towards the natural site compared to the old field site where no soil transfer was administered. Both species richness and cover for trees and shrubs in the soil transfer site increased towards the natural site, though this was not the case for herbs and grasses. One-way analysis of similarity (ANOSIM) showed significant (R = 0.55) separation in community composition between sites. The study concludes that soil transfer from intact renosterveld to degraded old fields is a promising restoration technique because it increases species diversity and cover and facilitates vegetation recovery. A significant restoration implication of this study is that soil transfer introduces key renosterveld native tree and shrub species that can facilitate successful restoration and act as restoration foci or nurse plants.
- Full Text:
- Authors: Ruwanza, Sheunesu
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148639 , vital:38758 , https://doi.org/10.3390/su12093833
- Description: The transfer of soils from intact vegetation communities to degraded ecosystems is seen as a promising restoration tool aimed at facilitating vegetation recovery. This study examined how topsoil transfer from intact renosterveld to degraded old fields improves vegetation diversity, cover, and composition. Transferred topsoil were overlaid on 30 quadrats, each measuring 1 m2, in May 2009. Eight years following the initial soil transfer, vegetation diversity in the soil transfer site showed an increase towards the natural site compared to the old field site where no soil transfer was administered. Both species richness and cover for trees and shrubs in the soil transfer site increased towards the natural site, though this was not the case for herbs and grasses. One-way analysis of similarity (ANOSIM) showed significant (R = 0.55) separation in community composition between sites. The study concludes that soil transfer from intact renosterveld to degraded old fields is a promising restoration technique because it increases species diversity and cover and facilitates vegetation recovery. A significant restoration implication of this study is that soil transfer introduces key renosterveld native tree and shrub species that can facilitate successful restoration and act as restoration foci or nurse plants.
- Full Text:
Touching matters: affective entanglements in Coronatime
- Bozalek, Vivienne, Newfield, Denise, Romano, Nike, Carette, Lieve, Naidu, Katharine, Mitchell, Veronica, Noble, Alex
- Authors: Bozalek, Vivienne , Newfield, Denise , Romano, Nike , Carette, Lieve , Naidu, Katharine , Mitchell, Veronica , Noble, Alex
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/160357 , vital:40438 , https://0-doi.org.wam.seals.ac.za/10.1177/1077800420960167
- Description: This article troubles touch as requiring embodied proximity, through an affective account of virtual touch during coronatime. Interested in doing academia differently, we started an online Barad readingwriting group from different locations. The coronatime void was not a vacuum, but a plenitude of possibilities for intimacy, pedagogy, learning, creativity, and adventure. Although physically apart, we met daily through Zoom, and we touched and were touched by each other and the texts we read. A montage of writing fragments and a collective artwork, based on the Massive_Micro project, highlight virtual touching. Undone, redone, and reconfigured, we became a diffractive human/nonhuman multiplicity.
- Full Text:
- Authors: Bozalek, Vivienne , Newfield, Denise , Romano, Nike , Carette, Lieve , Naidu, Katharine , Mitchell, Veronica , Noble, Alex
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/160357 , vital:40438 , https://0-doi.org.wam.seals.ac.za/10.1177/1077800420960167
- Description: This article troubles touch as requiring embodied proximity, through an affective account of virtual touch during coronatime. Interested in doing academia differently, we started an online Barad readingwriting group from different locations. The coronatime void was not a vacuum, but a plenitude of possibilities for intimacy, pedagogy, learning, creativity, and adventure. Although physically apart, we met daily through Zoom, and we touched and were touched by each other and the texts we read. A montage of writing fragments and a collective artwork, based on the Massive_Micro project, highlight virtual touching. Undone, redone, and reconfigured, we became a diffractive human/nonhuman multiplicity.
- Full Text:
Towards a capability maturity model for a cyber range
- Authors: Aschmann, Michael Joseph
- Date: 2020
- Subjects: Computer software -- Development , Computer security
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/163142 , vital:41013
- Description: This work describes research undertaken towards the development of a Capability Maturity Model (CMM) for Cyber Ranges (CRs) focused on cyber security. Global cyber security needs are on the rise, and the need for attribution within the cyber domain is of particular concern. This has prompted major efforts to enhance cyber capabilities within organisations to increase their total cyber resilience posture. These efforts include, but are not limited to, the testing of computational devices, networks, and applications, and cyber skills training focused on prevention, detection and cyber attack response. A cyber range allows for the testing of the computational environment. By developing cyber events within a confined virtual or sand-boxed cyber environment, a cyber range can prepare the next generation of cyber security specialists to handle a variety of potential cyber attacks. Cyber ranges have different purposes, each designed to fulfil a different computational testing and cyber training goal; consequently, cyber ranges can vary greatly in the level of variety, capability, maturity and complexity. As cyber ranges proliferate and become more and more valued as tools for cyber security, a method to classify or rate them becomes essential. Yet while a universal criteria for measuring cyber ranges in terms of their capability maturity levels becomes more critical, there are currently very limited resources for researchers aiming to perform this kind of work. For this reason, this work proposes and describes a CMM, designed to give organisations the ability to benchmark the capability maturity of a given cyber range. This research adopted a synthesised approach to the development of a CMM, grounded in prior research and focused on the production of a conceptual model that provides a useful level of abstraction. In order to achieve this goal, the core capability elements of a cyber range are defined with their relative importance, allowing for the development of a proposed classification cyber range levels. An analysis of data gathered during the course of an expert review, together with other research, further supported the development of the conceptual model. In the context of cyber range capability, classification will include the ability of the cyber range to perform its functions optimally with different core capability elements, focusing on the Measurement of Capability (MoC) with its elements, namely effect, performance and threat ability. Cyber range maturity can evolve over time and can be defined through the Measurement of Maturity (MoM) with its elements, namely people, processes, technology. The combination of these measurements utilising the CMM for a CR determines the capability maturity level of a CR. The primary outcome of this research is the proposed level-based CMM framework for a cyber range, developed using adopted and synthesised CMMs, the analysis of an expert review, and the mapping of the results.
- Full Text:
- Authors: Aschmann, Michael Joseph
- Date: 2020
- Subjects: Computer software -- Development , Computer security
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/163142 , vital:41013
- Description: This work describes research undertaken towards the development of a Capability Maturity Model (CMM) for Cyber Ranges (CRs) focused on cyber security. Global cyber security needs are on the rise, and the need for attribution within the cyber domain is of particular concern. This has prompted major efforts to enhance cyber capabilities within organisations to increase their total cyber resilience posture. These efforts include, but are not limited to, the testing of computational devices, networks, and applications, and cyber skills training focused on prevention, detection and cyber attack response. A cyber range allows for the testing of the computational environment. By developing cyber events within a confined virtual or sand-boxed cyber environment, a cyber range can prepare the next generation of cyber security specialists to handle a variety of potential cyber attacks. Cyber ranges have different purposes, each designed to fulfil a different computational testing and cyber training goal; consequently, cyber ranges can vary greatly in the level of variety, capability, maturity and complexity. As cyber ranges proliferate and become more and more valued as tools for cyber security, a method to classify or rate them becomes essential. Yet while a universal criteria for measuring cyber ranges in terms of their capability maturity levels becomes more critical, there are currently very limited resources for researchers aiming to perform this kind of work. For this reason, this work proposes and describes a CMM, designed to give organisations the ability to benchmark the capability maturity of a given cyber range. This research adopted a synthesised approach to the development of a CMM, grounded in prior research and focused on the production of a conceptual model that provides a useful level of abstraction. In order to achieve this goal, the core capability elements of a cyber range are defined with their relative importance, allowing for the development of a proposed classification cyber range levels. An analysis of data gathered during the course of an expert review, together with other research, further supported the development of the conceptual model. In the context of cyber range capability, classification will include the ability of the cyber range to perform its functions optimally with different core capability elements, focusing on the Measurement of Capability (MoC) with its elements, namely effect, performance and threat ability. Cyber range maturity can evolve over time and can be defined through the Measurement of Maturity (MoM) with its elements, namely people, processes, technology. The combination of these measurements utilising the CMM for a CR determines the capability maturity level of a CR. The primary outcome of this research is the proposed level-based CMM framework for a cyber range, developed using adopted and synthesised CMMs, the analysis of an expert review, and the mapping of the results.
- Full Text:
Towards development of a malaria diagnostic: Generation, screening and validation of novel aptamers recognising Plasmodium falciparum lactate dehydrogenase
- Authors: Frith, Kelly-Anne
- Date: 2020
- Subjects: Plasmodium falciparum , Malaria -- Chemotherapy , Oligonucleotides , Lactate dehydrogenase , Biochemical markers , Systematic evolution of ligands through exponential enrichment (SELEX)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142247 , vital:38062
- Description: Malaria, caused by infection with the Plasmodium parasite, is one of the leading causes of death in under-developed countries. Early detection is crucial for the effective treatment of malaria, particularly in cases where infection is due to Plasmodium falciparum. There is, therefore, an enduring need for portable, sensitive, reliable, accurate, durable, self-validating and cost-effective techniques for the rapid detection of malaria. Moreover, there is a demand to distinguish between various infectious species causing malaria. Research in the area of malarial biomarkers has identified a unique, species-specific, epitope of P. falciparum lactate dehydrogenase (PfLDH), enhancing prospects for the development of diagnostics capable of identifying the species causing malarial infection. In recent years, improvements have been made towards the development of rapid diagnostic tests for detecting malarial biomarkers. Owing to their low cost, ease of labeling, and high thermal stability (relative to antibodies), the development and synthesis of aptamers that target the malarial lactate dehydrogenase represents one of the key innovations in the field of rapid diagnostics for malaria. This study explored the generation of aptamers that specifically target P. falciparum. Two sets of aptamers with diagnostically-supportive functions were generated independently, through parallel SELEX of recombinantly-expressed, full-length Plasmodium falciparum lactate dehydrogenase (rPfLDH), and an oligopeptide comprising the P. falciparum-specific epitope on lactate dehydrogenase (LDHp). The latter offers a promising solution for generating aptamers capable of binding with high specificity to P. falciparum. In this work, an rLDH class of aptamers was generated when SELEX was performed using the full-length rPfLDH protein as the target and the LDHp class of aptamers was generated when SELEX was performed using the oligopeptide LDHp as a target. Aptamers were successfully generated through the process of SELEX (systematic evolution of ligands through exponential enrichment) following the study and application of several optimisation steps, particularly during the amplification stage of SELEX. Optimisation steps included the study of improvements in PCR conditions; role of surfactants (Triton-X), modifying the PCR clean-up protocol; and agarose gel excision. Structurally-relevant moieties with particular consensus sequences (GGTAG and GGCG) were found in aptamers both reported here and previously published, confirming their importance in recognition of the target. Novel moieties particular to this work (ATTAT and poly-A stretches) were identified. Clades of consensus sequences were identified in both the rLDH and LDHp groups of aptamers, where sequences in the rLDH clade did not show preferential binding to rPfLDH while those in the LDHp clade (particularly LDHp 3 and 18) were able to recognise and bind only LDHp. Of the 19 sequences returned from the parallel SELEX procedures for rPfLDH (11 sequences) and LDHp (8 sequences), six rPfLDH and all eight LDHp sequences underwent preliminary screening and those with low responses eliminated. Of the eight LDHp-targeting aptamer sequences, five were preliminarily shown to bind to LDHp, whereas only two rPfLDH-targeting sequences were shown to bind to the target (rLDH 4 and 7). To this small selection of rPfLDH oligonucleotide sequences, two more (rLDH 1 and 15) were chosen for further study based on their sequences, secondary and predicted tertiary conformations. Sequences chosen for further study were therefore: rLDH 1, 4, 7 and 15 in the rLDH class, and LDHp 1, 3, 11, 14 and 18 in the LDHp class. Binding properties of the aptamers towards their targets were investigated using enzyme-linked oligonucleotide assays (ELONA), fluorophore-linked oligonucleotide assays (FLONA), electromobility shift assays (EMSA), surface plasmon resonance (SPR), and GelRed dissociation assays, while applications towards aptasensors were explored using electrochemical impedance spectroscopy (EIS) and fluorescent microscopy. Some inconsistencies were seen for specific aptamer to target binding interactions using specific techniques; however, generally, binding to the targets was observed across the techniques assessed. These varied responses demonstrate the need to screen and validate aptamers using a variety of techniques and platforms not necessarily specific for the proposed application. From the aptamer binding screening studies using ELONA, the most promising aptamers generated were identified as LDHp 11, rLDH 4, rLDH 7 and rLDH 15. Aptamer rLDH 4, which was generated against rPfLDH, exhibited preferential and specific binding to the lactate dehydrogenase from P. falciparum, over the recombinantly-expressed lactate dehydrogenase from Plasmodium vivax (rPvLDH), albeit with lowered responses compared to LDHp 11 in ELONA and EMSA studies. However, in kinetic ELONA studies rLDH 4 showed binding to both rPfLDH and rPvLDH. Aptamer rLDH 7 showed high affinity for rPfLDH and rPvLDH in kinetic studies using ELONA. However, screening studies with ELONA indicates that aptamer rLDH 7 may not be suitable for diagnostic tests in serum samples given its non-specific binding to human serum albumin (HSA). Aptamer rLDH 15 exhibited species specificity for rPfLDH in screening studies using ELONA but showed affinity towards rPvLDH (albeit lower relative to its affinity for rPfLDH) in kinetic studies using ELONA. LDHp 11, generated against the PfLDH peptide, showed a clear preference for rPfLDH when compared to rPvLDH and other control proteins, in both sets of ELONA studies conducted, as well as EMSA, thus possessing a strong ability to identify the presence of Plasmodium falciparum owing to its generation against the species-specific epitope. While LDHp 1 demonstrated binding to plasmodial LDH in a flow-through system (SPR), so reiterating ELONA responses, it did not perform well in the remaining methodologies. Aptamers rLDH 1 and 15 and LDHp 3, 14 and 18 exhibited a mixed set of results throughout the target protein screening analyses and were, thus, not considered for selective binding in P. falciparum parasite bodies. In studies aimed at exploring biosensor assemblies utilising the developed aptamers, both rLDH 4 and LDHp 11, along with rLDH 7, LDHp 1 and pL1, demonstrated in situ binding to the native PfLDH in fluorescent microscopy. LDHp 11 exhibited FITC-based fluorescence equivalent to the anti-rPfLDHp IgY antibody in confocal fluorescent microscopy indicating superior binding to the native PfLDH compared to the remaining aptamers. An examination of electrochemical impedance as a platform for a biosensor assembly did not, in these studies, exhibit the required sensitivity using physiologically relevant concentrations of analyte expected for pLDH following infection with Plasmodium spp. Malstat/LDH activity was explored for application in a colorimetric aptasensor. A decrease in both rPfLDH and rPvLDH activity was observed following incubation with the tested aptamers, but rLDH 1, rLDH 7 and LDHp 14 did not exhibit similar decreases in rPvLDH activity. Aptamers rLDH 1, 4 and 7 and LDHp 11 and 14 were, therefore, not selected as candidates for LDH capture in LDH activity-based diagnostic devices for P. falciparum. The decreases in pLDH activity in the presence of aptamers could hold promise as direct or antagonistic malaria therapeutic agents. Preliminary studies on the application of aptamers as malaria therapeutic agents, while of interest, should be viewed with due caution given the challenges of aptamers reaching the intracellular native plasmodial LDH hosted within the red blood cells. In conclusion, this work has shown the ability of the LDHp 11 aptamer, generated in these studies, to selectively bind rPfLDH over rPvLDH, and to bind to the native PfLDH in fluorescent microscopy, indicating that this aptamer holds promise as a biorecognition element in malaria biosensors and other diagnostic devices for the detection, and differentiation, of P. falciparum and P. vivax. The use of a species-specific epitope of P. falciparum as a target in aptamer generation paves the way for similar such studies aimed at generating aptamers with species selectivity for other Plasmodium species.
- Full Text:
- Authors: Frith, Kelly-Anne
- Date: 2020
- Subjects: Plasmodium falciparum , Malaria -- Chemotherapy , Oligonucleotides , Lactate dehydrogenase , Biochemical markers , Systematic evolution of ligands through exponential enrichment (SELEX)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142247 , vital:38062
- Description: Malaria, caused by infection with the Plasmodium parasite, is one of the leading causes of death in under-developed countries. Early detection is crucial for the effective treatment of malaria, particularly in cases where infection is due to Plasmodium falciparum. There is, therefore, an enduring need for portable, sensitive, reliable, accurate, durable, self-validating and cost-effective techniques for the rapid detection of malaria. Moreover, there is a demand to distinguish between various infectious species causing malaria. Research in the area of malarial biomarkers has identified a unique, species-specific, epitope of P. falciparum lactate dehydrogenase (PfLDH), enhancing prospects for the development of diagnostics capable of identifying the species causing malarial infection. In recent years, improvements have been made towards the development of rapid diagnostic tests for detecting malarial biomarkers. Owing to their low cost, ease of labeling, and high thermal stability (relative to antibodies), the development and synthesis of aptamers that target the malarial lactate dehydrogenase represents one of the key innovations in the field of rapid diagnostics for malaria. This study explored the generation of aptamers that specifically target P. falciparum. Two sets of aptamers with diagnostically-supportive functions were generated independently, through parallel SELEX of recombinantly-expressed, full-length Plasmodium falciparum lactate dehydrogenase (rPfLDH), and an oligopeptide comprising the P. falciparum-specific epitope on lactate dehydrogenase (LDHp). The latter offers a promising solution for generating aptamers capable of binding with high specificity to P. falciparum. In this work, an rLDH class of aptamers was generated when SELEX was performed using the full-length rPfLDH protein as the target and the LDHp class of aptamers was generated when SELEX was performed using the oligopeptide LDHp as a target. Aptamers were successfully generated through the process of SELEX (systematic evolution of ligands through exponential enrichment) following the study and application of several optimisation steps, particularly during the amplification stage of SELEX. Optimisation steps included the study of improvements in PCR conditions; role of surfactants (Triton-X), modifying the PCR clean-up protocol; and agarose gel excision. Structurally-relevant moieties with particular consensus sequences (GGTAG and GGCG) were found in aptamers both reported here and previously published, confirming their importance in recognition of the target. Novel moieties particular to this work (ATTAT and poly-A stretches) were identified. Clades of consensus sequences were identified in both the rLDH and LDHp groups of aptamers, where sequences in the rLDH clade did not show preferential binding to rPfLDH while those in the LDHp clade (particularly LDHp 3 and 18) were able to recognise and bind only LDHp. Of the 19 sequences returned from the parallel SELEX procedures for rPfLDH (11 sequences) and LDHp (8 sequences), six rPfLDH and all eight LDHp sequences underwent preliminary screening and those with low responses eliminated. Of the eight LDHp-targeting aptamer sequences, five were preliminarily shown to bind to LDHp, whereas only two rPfLDH-targeting sequences were shown to bind to the target (rLDH 4 and 7). To this small selection of rPfLDH oligonucleotide sequences, two more (rLDH 1 and 15) were chosen for further study based on their sequences, secondary and predicted tertiary conformations. Sequences chosen for further study were therefore: rLDH 1, 4, 7 and 15 in the rLDH class, and LDHp 1, 3, 11, 14 and 18 in the LDHp class. Binding properties of the aptamers towards their targets were investigated using enzyme-linked oligonucleotide assays (ELONA), fluorophore-linked oligonucleotide assays (FLONA), electromobility shift assays (EMSA), surface plasmon resonance (SPR), and GelRed dissociation assays, while applications towards aptasensors were explored using electrochemical impedance spectroscopy (EIS) and fluorescent microscopy. Some inconsistencies were seen for specific aptamer to target binding interactions using specific techniques; however, generally, binding to the targets was observed across the techniques assessed. These varied responses demonstrate the need to screen and validate aptamers using a variety of techniques and platforms not necessarily specific for the proposed application. From the aptamer binding screening studies using ELONA, the most promising aptamers generated were identified as LDHp 11, rLDH 4, rLDH 7 and rLDH 15. Aptamer rLDH 4, which was generated against rPfLDH, exhibited preferential and specific binding to the lactate dehydrogenase from P. falciparum, over the recombinantly-expressed lactate dehydrogenase from Plasmodium vivax (rPvLDH), albeit with lowered responses compared to LDHp 11 in ELONA and EMSA studies. However, in kinetic ELONA studies rLDH 4 showed binding to both rPfLDH and rPvLDH. Aptamer rLDH 7 showed high affinity for rPfLDH and rPvLDH in kinetic studies using ELONA. However, screening studies with ELONA indicates that aptamer rLDH 7 may not be suitable for diagnostic tests in serum samples given its non-specific binding to human serum albumin (HSA). Aptamer rLDH 15 exhibited species specificity for rPfLDH in screening studies using ELONA but showed affinity towards rPvLDH (albeit lower relative to its affinity for rPfLDH) in kinetic studies using ELONA. LDHp 11, generated against the PfLDH peptide, showed a clear preference for rPfLDH when compared to rPvLDH and other control proteins, in both sets of ELONA studies conducted, as well as EMSA, thus possessing a strong ability to identify the presence of Plasmodium falciparum owing to its generation against the species-specific epitope. While LDHp 1 demonstrated binding to plasmodial LDH in a flow-through system (SPR), so reiterating ELONA responses, it did not perform well in the remaining methodologies. Aptamers rLDH 1 and 15 and LDHp 3, 14 and 18 exhibited a mixed set of results throughout the target protein screening analyses and were, thus, not considered for selective binding in P. falciparum parasite bodies. In studies aimed at exploring biosensor assemblies utilising the developed aptamers, both rLDH 4 and LDHp 11, along with rLDH 7, LDHp 1 and pL1, demonstrated in situ binding to the native PfLDH in fluorescent microscopy. LDHp 11 exhibited FITC-based fluorescence equivalent to the anti-rPfLDHp IgY antibody in confocal fluorescent microscopy indicating superior binding to the native PfLDH compared to the remaining aptamers. An examination of electrochemical impedance as a platform for a biosensor assembly did not, in these studies, exhibit the required sensitivity using physiologically relevant concentrations of analyte expected for pLDH following infection with Plasmodium spp. Malstat/LDH activity was explored for application in a colorimetric aptasensor. A decrease in both rPfLDH and rPvLDH activity was observed following incubation with the tested aptamers, but rLDH 1, rLDH 7 and LDHp 14 did not exhibit similar decreases in rPvLDH activity. Aptamers rLDH 1, 4 and 7 and LDHp 11 and 14 were, therefore, not selected as candidates for LDH capture in LDH activity-based diagnostic devices for P. falciparum. The decreases in pLDH activity in the presence of aptamers could hold promise as direct or antagonistic malaria therapeutic agents. Preliminary studies on the application of aptamers as malaria therapeutic agents, while of interest, should be viewed with due caution given the challenges of aptamers reaching the intracellular native plasmodial LDH hosted within the red blood cells. In conclusion, this work has shown the ability of the LDHp 11 aptamer, generated in these studies, to selectively bind rPfLDH over rPvLDH, and to bind to the native PfLDH in fluorescent microscopy, indicating that this aptamer holds promise as a biorecognition element in malaria biosensors and other diagnostic devices for the detection, and differentiation, of P. falciparum and P. vivax. The use of a species-specific epitope of P. falciparum as a target in aptamer generation paves the way for similar such studies aimed at generating aptamers with species selectivity for other Plasmodium species.
- Full Text:
Towards realising the benefits of citizen participation in environmental monitoring: a case study in an Eastern Cape natural resource management programme
- Authors: Mtati, Nosiseko
- Date: 2020
- Subjects: Tsitsa Project , Rural development projects -- South Africa -- Eastern Cape , Environmental monitoring -- South Africa -- Tsitsa River , Environmental monitoring -- Citizen participation -- South Africa -- Tsitsa River , Water supply, Agricultural -- South Africa -- Tsitsa River , Environmental education -- South Africa
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/167562 , vital:41492
- Description: The Tsitsa Project focusses on land use management and rural livelihoods in the Tsitsa River catchment in the Eastern Cape Province of South Africa. It is funded by the Department of Environmental Affairs and the environmental monitoring initiative is implemented by Rhodes University, where I am employed as the catchment coordinator. This study explores the environmental monitoring initiative within the bigger Tsitsa Project. Community members in the catchment monitor sediment transportation in the Tsitsa River and its tributaries, which originally became of interest because it is proposed that a dam (Ntabelanga Dam) be established here. This study aims to understand citizen environmental monitoring in the Tsitsa Project; what the project managers regarded as benefits; and how the monitors themselves perceived benefits of participating as monitors. A realist approach was followed, in order to understand the connections between the context and the mechanisms in the project, and how these combined to result in the outcomes observed. Realist research emphasises the importance of context in shaping outcomes such as the achieved benefits of citizen monitoring. Data was collected using a case study method, where each individual monitor and their particular context, was regarded as a case. Semistructured interviews were conducted with 17 monitors and five Tsitsa Project staff; this was supported by field notes and the reviewing of project documents including field reports. The realist analysis looked at the context of the monitors in general and the mechanisms applied by the project in recruiting, training and managing the monitors. A second layer of mechanisms was identified as those responses from the monitors to what the project was introducing to them. Outcomes were both positive and negative, including how long monitors remained in the initiative, what benefits they derived from the process, and what potential benefits they did not achieve. This included lost opportunities to provide recognition for skills and experience gained. Recommendations are made regarding the recruitment, training and management of monitors, to optimise benefits for the monitors, the host institution and the initiative’s staff. The study is significant because of its particular yet representative characteristics and it will assist both the Tsitsa Project, which aims to expand its citizen environmental monitoring initiative, as well as wider Natural Resource Management Programmes in South Africa. It is also hoped that it will contribute to the literature on environmental monitoring as a little researched form of citizen science globally.
- Full Text:
- Authors: Mtati, Nosiseko
- Date: 2020
- Subjects: Tsitsa Project , Rural development projects -- South Africa -- Eastern Cape , Environmental monitoring -- South Africa -- Tsitsa River , Environmental monitoring -- Citizen participation -- South Africa -- Tsitsa River , Water supply, Agricultural -- South Africa -- Tsitsa River , Environmental education -- South Africa
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/167562 , vital:41492
- Description: The Tsitsa Project focusses on land use management and rural livelihoods in the Tsitsa River catchment in the Eastern Cape Province of South Africa. It is funded by the Department of Environmental Affairs and the environmental monitoring initiative is implemented by Rhodes University, where I am employed as the catchment coordinator. This study explores the environmental monitoring initiative within the bigger Tsitsa Project. Community members in the catchment monitor sediment transportation in the Tsitsa River and its tributaries, which originally became of interest because it is proposed that a dam (Ntabelanga Dam) be established here. This study aims to understand citizen environmental monitoring in the Tsitsa Project; what the project managers regarded as benefits; and how the monitors themselves perceived benefits of participating as monitors. A realist approach was followed, in order to understand the connections between the context and the mechanisms in the project, and how these combined to result in the outcomes observed. Realist research emphasises the importance of context in shaping outcomes such as the achieved benefits of citizen monitoring. Data was collected using a case study method, where each individual monitor and their particular context, was regarded as a case. Semistructured interviews were conducted with 17 monitors and five Tsitsa Project staff; this was supported by field notes and the reviewing of project documents including field reports. The realist analysis looked at the context of the monitors in general and the mechanisms applied by the project in recruiting, training and managing the monitors. A second layer of mechanisms was identified as those responses from the monitors to what the project was introducing to them. Outcomes were both positive and negative, including how long monitors remained in the initiative, what benefits they derived from the process, and what potential benefits they did not achieve. This included lost opportunities to provide recognition for skills and experience gained. Recommendations are made regarding the recruitment, training and management of monitors, to optimise benefits for the monitors, the host institution and the initiative’s staff. The study is significant because of its particular yet representative characteristics and it will assist both the Tsitsa Project, which aims to expand its citizen environmental monitoring initiative, as well as wider Natural Resource Management Programmes in South Africa. It is also hoped that it will contribute to the literature on environmental monitoring as a little researched form of citizen science globally.
- Full Text:
Towards the development of a bio-fertiliser using mixed liquor from high rate algal oxidation ponds
- Authors: Masudi, Wiya Léon
- Date: 2020
- Subjects: Biofertilizers , Microalgae - Biotechnology , Algae -- Culture
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/142969 , vital:38181
- Description: Mixed liquor includes consortia of microalgae and bacteria produced in high rate algal oxidation ponds (HRAOPs). The consortia of microalgae and bacteria occur as flocs called microalgae-bacterial flocs (MaB-flocs). This study aimed to source bacteria from MaB-flocs generated in HRAOPs and, after isolation and identification, evaluate their potential as plant growth promoting (PGP) microorganisms. Twelve bacterial strains namely ECCN 1b, ECCN 2b, ECCN 3b, ECCN 4b, ECCN 5b, ECCN 6b, ECCN 7b, ECCN 8b, ECCN 9b, ECCN 10b, ECCN 11b, and ECCN 12b were successfully isolated and their molecular identity established using amplified 16S rRNA gene sequence analysis that was compared to sequences deposited in the NCBI gene database. Blast analysis identified these isolates at the genus level as Bacillus strain ECCN 1b, Fictibacillus strain ECCN 2b, Bacillus strain ECCN 3b, Aeromonas strain ECCN 4b, Exiguobacterium strain ECCN 5b, Arthrobacter strain ECCN 6b, Enterobacter strain ECCN 7b, Exiguobacterium strain ECCN 8b, Microbacterium strain ECCN 9b, Pseudomonas ECCN strain 10b, Ancylobacter strain ECCN 11b and Microbacterium strain ECCN 12b. These isolates were able to grow in nutrient broth in a pH range between 6 and 10, with the best growth achieved at pH 8 to 9. The results on the use of carbon substrate revealed that 5 strains including Arthrobacter strain ECCN 6b, Aeromonas strain ECCN 4b, Pseudomonas strain ECCN 10b, Enterobacter strain ECCN 7b and Bacillus strain ECCN 3b were capable of using glucose, sucrose and mannitol. No faecal coliforms were found. However, of the 12 isolates screened for bio-fertilisation potential, Bacillus strain ECCN 1b, Fictibacillus strain ECCN 2b, Bacillus strain ECCN 3b, Aeromonas strain ECCN 4b, Exiguobacterium strain ECCN 5b, Arthrobacter strain ECCN 6b, Enterobacter ECCN strain 7b, Exiguobacterium strain ECCN 8b and Pseudomonas strain ECCN 10b showed multifunctional plant growth promoting (PGP) potential. The potential for PGP included the production of ammonium-N, solubilisation of phosphate-P and potassium-K, oxidation of Mn and production of auxin, indole-3-acetic acid (IAA). Results are discussed in terms of the amount or concentration (mg L-1) of plant essential nutrient and growth regulator produced by these isolated bacteria. Even so, further studies are needed to test and confirm the bio-fertiliser and plant growth promoting activity of these strains in pot trials and field experiments, or both.
- Full Text:
- Authors: Masudi, Wiya Léon
- Date: 2020
- Subjects: Biofertilizers , Microalgae - Biotechnology , Algae -- Culture
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/142969 , vital:38181
- Description: Mixed liquor includes consortia of microalgae and bacteria produced in high rate algal oxidation ponds (HRAOPs). The consortia of microalgae and bacteria occur as flocs called microalgae-bacterial flocs (MaB-flocs). This study aimed to source bacteria from MaB-flocs generated in HRAOPs and, after isolation and identification, evaluate their potential as plant growth promoting (PGP) microorganisms. Twelve bacterial strains namely ECCN 1b, ECCN 2b, ECCN 3b, ECCN 4b, ECCN 5b, ECCN 6b, ECCN 7b, ECCN 8b, ECCN 9b, ECCN 10b, ECCN 11b, and ECCN 12b were successfully isolated and their molecular identity established using amplified 16S rRNA gene sequence analysis that was compared to sequences deposited in the NCBI gene database. Blast analysis identified these isolates at the genus level as Bacillus strain ECCN 1b, Fictibacillus strain ECCN 2b, Bacillus strain ECCN 3b, Aeromonas strain ECCN 4b, Exiguobacterium strain ECCN 5b, Arthrobacter strain ECCN 6b, Enterobacter strain ECCN 7b, Exiguobacterium strain ECCN 8b, Microbacterium strain ECCN 9b, Pseudomonas ECCN strain 10b, Ancylobacter strain ECCN 11b and Microbacterium strain ECCN 12b. These isolates were able to grow in nutrient broth in a pH range between 6 and 10, with the best growth achieved at pH 8 to 9. The results on the use of carbon substrate revealed that 5 strains including Arthrobacter strain ECCN 6b, Aeromonas strain ECCN 4b, Pseudomonas strain ECCN 10b, Enterobacter strain ECCN 7b and Bacillus strain ECCN 3b were capable of using glucose, sucrose and mannitol. No faecal coliforms were found. However, of the 12 isolates screened for bio-fertilisation potential, Bacillus strain ECCN 1b, Fictibacillus strain ECCN 2b, Bacillus strain ECCN 3b, Aeromonas strain ECCN 4b, Exiguobacterium strain ECCN 5b, Arthrobacter strain ECCN 6b, Enterobacter ECCN strain 7b, Exiguobacterium strain ECCN 8b and Pseudomonas strain ECCN 10b showed multifunctional plant growth promoting (PGP) potential. The potential for PGP included the production of ammonium-N, solubilisation of phosphate-P and potassium-K, oxidation of Mn and production of auxin, indole-3-acetic acid (IAA). Results are discussed in terms of the amount or concentration (mg L-1) of plant essential nutrient and growth regulator produced by these isolated bacteria. Even so, further studies are needed to test and confirm the bio-fertiliser and plant growth promoting activity of these strains in pot trials and field experiments, or both.
- Full Text:
Towards understanding how exploitation influences the wild energetic response of marine fish to temperature variability
- Authors: Skeeles, Michael Richard
- Date: 2020
- Subjects: Chrysoblepus laticeps -- Climatic factors , Sparidae -- Genetics , Sparidae -- South Africa -- Climatic factors
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/145133 , vital:38411
- Description: Exploitation of fish populations can exacerbate the effects of climate change, yet our understanding of their synergistic effects remains limited. As fish are increasingly exposed to temperatures on the edges of their optimal thermal performance window, their physiological response is expected to shape their future performance. It is therefore concerning that exploitation can select for specific physiological phenotypes, as this may affect fished populations’ physiological response to temperature change. A recent laboratory study revealed fewer high-performance metabolic-scope phenotypes in an exploited population of the marine Sparid Chrysoblepus laticeps across a range of experimental temperatures in comparison to an unexploited population. This suggested that individuals in exploited populations may have less available energy for aerobic performance at thermal extremes, which may reduce the resilience of the population to changes in temperature. However, since laboratory experiments exclude numerous other variables that fish encounter in the wild, it was necessary to test this finding in a natural setting. This thesis aimed to further develop the laboratory study by assessing whether exploitation effects the wild energetic response of C. laticeps to thermal variability. To achieve this, the field metabolic rate of C. laticeps, a resident and endemic South African fish, from a near-pristine population (Tsitsikamma National Park) and a heavily exploited population (Port Elizabeth) was compared using acoustic accelerometry. A laboratory-based study using a swim-tunnel respirometer and accelerometer transmitters was conducted to develop a model to predict metabolic rate from acceleration data at temperatures from 10 to 22⁰C. Acceleration, temperature, mass and population (exploited/unexploited) were found to be the best predictors of the metabolic rate of C. laticeps and were incorporated into the model to estimate the field metabolic rate of fish tagged with acoustic accelerometers in the wild. To examine the combined effects of temperature and exploitation on the field metabolic rate of C. laticeps in their natural state, two fine-scale telemetry arrays with temperature loggers were used to assess the acceleration of the fish across different temperatures in the wild for three months during a period of high thermal variability. Ten fish from the exploited and unexploited populations were caught, surgically implanted with accelerometer transmitters and released back into the wild. Close to 500 000 and 400 000 acceleration estimates were recorded from wild exploited and unexploited fish, respectively. The field metabolic rate of both populations was estimated by combining the field acceleration and temperature data with the laboratory calibration model. The field metabolic rate of C. laticeps from the exploited population was constrained near cold and warm extremes compared to no constraints observed in the unexploited population. This was attributed to reduced inter-individual variability in the field metabolic rate-temperature relationship within the exploited population. There appeared to be a greater proportion of individuals that maintained a high field metabolic rate at extreme temperatures in the unexploited population. In contrast, all but one fish from the exploited population did not maintain a high field metabolic rate at extreme temperatures. These findings aligned with the laboratory-based metabolic-scope study on both populations of C. laticeps and demonstrate that passive-fishing may be removing thermally tolerant individuals and rendering exploited populations less resilient to thermal change. These findings are discussed in the context of fisheries management and particularly on the role that marine protected areas could play in maintaining physiological diversity, and therefore the resilience of fish in the Anthropocene. This study highlights the importance of applied conservation physiology in understanding the consequences of fisheries-induced evolution in an increasingly variable climate.
- Full Text:
- Authors: Skeeles, Michael Richard
- Date: 2020
- Subjects: Chrysoblepus laticeps -- Climatic factors , Sparidae -- Genetics , Sparidae -- South Africa -- Climatic factors
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/145133 , vital:38411
- Description: Exploitation of fish populations can exacerbate the effects of climate change, yet our understanding of their synergistic effects remains limited. As fish are increasingly exposed to temperatures on the edges of their optimal thermal performance window, their physiological response is expected to shape their future performance. It is therefore concerning that exploitation can select for specific physiological phenotypes, as this may affect fished populations’ physiological response to temperature change. A recent laboratory study revealed fewer high-performance metabolic-scope phenotypes in an exploited population of the marine Sparid Chrysoblepus laticeps across a range of experimental temperatures in comparison to an unexploited population. This suggested that individuals in exploited populations may have less available energy for aerobic performance at thermal extremes, which may reduce the resilience of the population to changes in temperature. However, since laboratory experiments exclude numerous other variables that fish encounter in the wild, it was necessary to test this finding in a natural setting. This thesis aimed to further develop the laboratory study by assessing whether exploitation effects the wild energetic response of C. laticeps to thermal variability. To achieve this, the field metabolic rate of C. laticeps, a resident and endemic South African fish, from a near-pristine population (Tsitsikamma National Park) and a heavily exploited population (Port Elizabeth) was compared using acoustic accelerometry. A laboratory-based study using a swim-tunnel respirometer and accelerometer transmitters was conducted to develop a model to predict metabolic rate from acceleration data at temperatures from 10 to 22⁰C. Acceleration, temperature, mass and population (exploited/unexploited) were found to be the best predictors of the metabolic rate of C. laticeps and were incorporated into the model to estimate the field metabolic rate of fish tagged with acoustic accelerometers in the wild. To examine the combined effects of temperature and exploitation on the field metabolic rate of C. laticeps in their natural state, two fine-scale telemetry arrays with temperature loggers were used to assess the acceleration of the fish across different temperatures in the wild for three months during a period of high thermal variability. Ten fish from the exploited and unexploited populations were caught, surgically implanted with accelerometer transmitters and released back into the wild. Close to 500 000 and 400 000 acceleration estimates were recorded from wild exploited and unexploited fish, respectively. The field metabolic rate of both populations was estimated by combining the field acceleration and temperature data with the laboratory calibration model. The field metabolic rate of C. laticeps from the exploited population was constrained near cold and warm extremes compared to no constraints observed in the unexploited population. This was attributed to reduced inter-individual variability in the field metabolic rate-temperature relationship within the exploited population. There appeared to be a greater proportion of individuals that maintained a high field metabolic rate at extreme temperatures in the unexploited population. In contrast, all but one fish from the exploited population did not maintain a high field metabolic rate at extreme temperatures. These findings aligned with the laboratory-based metabolic-scope study on both populations of C. laticeps and demonstrate that passive-fishing may be removing thermally tolerant individuals and rendering exploited populations less resilient to thermal change. These findings are discussed in the context of fisheries management and particularly on the role that marine protected areas could play in maintaining physiological diversity, and therefore the resilience of fish in the Anthropocene. This study highlights the importance of applied conservation physiology in understanding the consequences of fisheries-induced evolution in an increasingly variable climate.
- Full Text:
Tracing the Voice of Protest in Selected Oral Literature:
- Authors: Kaschula, Russell H
- Date: 2020
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/174452 , vital:42479 , ISBN 9783030555177
- Description: This chapter aims to present the notion of “protest” as a contested arena in the production of oral literature, against the backdrop of continued and contested sociopolitical change in Africa. This contestation can be politically based, gender based and sometimes even based in religion. The chapter looks specifically at poetry, songs and the folktale to establish how the “voice of protest” has been presented over time in relation to specific African countries such as Senegal, South Africa, Somali, Guinea, Kenya, Tanzania, Malawi, Ethiopia, Nigeria, Zimbabwe and Lesotho. Poetic protest as part of political protest is also discussed. Furthermore, the chapter seeks to explore how this “voice of protest” has been received, both from an audience point of view and from the point of view of those who control power.
- Full Text:
- Authors: Kaschula, Russell H
- Date: 2020
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/174452 , vital:42479 , ISBN 9783030555177
- Description: This chapter aims to present the notion of “protest” as a contested arena in the production of oral literature, against the backdrop of continued and contested sociopolitical change in Africa. This contestation can be politically based, gender based and sometimes even based in religion. The chapter looks specifically at poetry, songs and the folktale to establish how the “voice of protest” has been presented over time in relation to specific African countries such as Senegal, South Africa, Somali, Guinea, Kenya, Tanzania, Malawi, Ethiopia, Nigeria, Zimbabwe and Lesotho. Poetic protest as part of political protest is also discussed. Furthermore, the chapter seeks to explore how this “voice of protest” has been received, both from an audience point of view and from the point of view of those who control power.
- Full Text:
Transformative ICT education practices in rural secondary schools for developmental needs and realities: the Eastern Cape Province, South Africa
- Authors: Simuja, Clement
- Date: 2020
- Subjects: Education, Secondary -- South Africa -- Data processing , Information technology -- Study and teaching (Secondary) --South Africa , Educational technology -- Developing countries , Rural development -- Developing countries , Computer-assisted instruction -- South Africa -- Eastern Cape , Internet in education -- South Africa , Rural schools -- South Africa -- Eastern Cape , Community and school -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/150631 , vital:38991
- Description: The perceived social development significance of Information and Communication Technology (ICT) has dramatically expanded the domains in which this cluster of ICTs is being discussed and acted upon. The action to promote community development in rural areas in South Africa has made its way into the introduction of ICT education in secondary schools. Since rural secondary schools form part of the framework for rural communities, they are being challenged to provide ICT education that makes a difference in learners’ lives. This requires engaging education practices that inspire learners to construct knowledge of ICT that does not only respond to examination purposes but rather, to the needs and development aspirations of the community. This research examines the experience of engaging learners and communities in socially informed ICT education in rural secondary schools. Specifically, it seeks to develop a critique of current practices involved in ICT education in rural secondary schools, and explores plausible alternatives to such practices that would make ICT education more transformative and structured towards the developmental concerns of communities. The main empirical focus for the research was five rural secondary schools in the Eastern Cape Province in South Africa. The research involved 53 participants that participated in a socially informed ICT training process. The training was designed to inspire participants to share their self-defined ICT education and ICT knowledge experiences. Critical Action Learning and Philosophical Inquiry provided the methodological framework, whilst the theoretical framework draws on Foucault’s philosophical ideas on power-knowledge relations. Through this theoretical analysis, the research examines the dynamic interplay of practices in ICT education with the values, ideals, and knowledge that form the core-life experiences of learners and rural communities. The research findings of this study indicate that current ICT education practices in rural secondary schools are endowed with ideologies that are affecting learners’ identity, social experiences, power, and ownership of the reflective meaning of using ICTs in community development. The contribution of this thesis lies in demonstrating ways that reframe ICT education transformatively, and more specifically its practices in the light of the way power, identity, ownership and social experience construct and offer learners a transformative view of self and the world. This could enable ICT education to fulfil the potential of contributing to social development in rural communities. The thesis culminates by presenting a theoretical framework that articulates the structural and authoritative components of ICT education practices – these relate to learners’ conscious understandings and represented thoughts, sensations and meanings embedded in the context, and actions and locations of using their knowledge of ICT.
- Full Text:
- Authors: Simuja, Clement
- Date: 2020
- Subjects: Education, Secondary -- South Africa -- Data processing , Information technology -- Study and teaching (Secondary) --South Africa , Educational technology -- Developing countries , Rural development -- Developing countries , Computer-assisted instruction -- South Africa -- Eastern Cape , Internet in education -- South Africa , Rural schools -- South Africa -- Eastern Cape , Community and school -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/150631 , vital:38991
- Description: The perceived social development significance of Information and Communication Technology (ICT) has dramatically expanded the domains in which this cluster of ICTs is being discussed and acted upon. The action to promote community development in rural areas in South Africa has made its way into the introduction of ICT education in secondary schools. Since rural secondary schools form part of the framework for rural communities, they are being challenged to provide ICT education that makes a difference in learners’ lives. This requires engaging education practices that inspire learners to construct knowledge of ICT that does not only respond to examination purposes but rather, to the needs and development aspirations of the community. This research examines the experience of engaging learners and communities in socially informed ICT education in rural secondary schools. Specifically, it seeks to develop a critique of current practices involved in ICT education in rural secondary schools, and explores plausible alternatives to such practices that would make ICT education more transformative and structured towards the developmental concerns of communities. The main empirical focus for the research was five rural secondary schools in the Eastern Cape Province in South Africa. The research involved 53 participants that participated in a socially informed ICT training process. The training was designed to inspire participants to share their self-defined ICT education and ICT knowledge experiences. Critical Action Learning and Philosophical Inquiry provided the methodological framework, whilst the theoretical framework draws on Foucault’s philosophical ideas on power-knowledge relations. Through this theoretical analysis, the research examines the dynamic interplay of practices in ICT education with the values, ideals, and knowledge that form the core-life experiences of learners and rural communities. The research findings of this study indicate that current ICT education practices in rural secondary schools are endowed with ideologies that are affecting learners’ identity, social experiences, power, and ownership of the reflective meaning of using ICTs in community development. The contribution of this thesis lies in demonstrating ways that reframe ICT education transformatively, and more specifically its practices in the light of the way power, identity, ownership and social experience construct and offer learners a transformative view of self and the world. This could enable ICT education to fulfil the potential of contributing to social development in rural communities. The thesis culminates by presenting a theoretical framework that articulates the structural and authoritative components of ICT education practices – these relate to learners’ conscious understandings and represented thoughts, sensations and meanings embedded in the context, and actions and locations of using their knowledge of ICT.
- Full Text:
Transformative Power of Language Policies in Higher Education:
- Kaschula, Russell H, Docrat, Zakeera
- Authors: Kaschula, Russell H , Docrat, Zakeera
- Date: 2020
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/174502 , vital:42483 , ISBN 9781108498821
- Description: There is a disjuncture between the intentions of the South African constitutional provisions as contained in Section 6, which prescribe that all eleven official languages be treated equitably, and what is happening on the ground at the institutions of higher learning. In these institutions, English remains the primary language of instruction. African languages are encouraged as support languages in certain instances, but no institution has an African language as a medium of instruction (see for example the Rhodes Language Policy, 2019). This chapter calls into question the use of language and argues for purposive interpretation and practical implementation of the constitutional provisions on language. A proper and linguistically sound understanding of multilingualism as a developmental resource–educational, legal and societal–needs to emerge (Wolff, 2016). The constitutional aspects are explicated in the legislative and policy frameworks discussed in this chapter.
- Full Text:
- Authors: Kaschula, Russell H , Docrat, Zakeera
- Date: 2020
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/174502 , vital:42483 , ISBN 9781108498821
- Description: There is a disjuncture between the intentions of the South African constitutional provisions as contained in Section 6, which prescribe that all eleven official languages be treated equitably, and what is happening on the ground at the institutions of higher learning. In these institutions, English remains the primary language of instruction. African languages are encouraged as support languages in certain instances, but no institution has an African language as a medium of instruction (see for example the Rhodes Language Policy, 2019). This chapter calls into question the use of language and argues for purposive interpretation and practical implementation of the constitutional provisions on language. A proper and linguistically sound understanding of multilingualism as a developmental resource–educational, legal and societal–needs to emerge (Wolff, 2016). The constitutional aspects are explicated in the legislative and policy frameworks discussed in this chapter.
- Full Text:
Transforming environmental health practitioners’ knowledge-sharing practices through inter-agency formative intervention workshops
- Masilela, Priscilla, Olvitt, Lausanne L
- Authors: Masilela, Priscilla , Olvitt, Lausanne L
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/372809 , vital:66624 , xlink:href="https://doi.org/10.1080/0158037X.2020.1717458"
- Description: Home-based care facilities provide basic healthcare services to people too sick or frail to access formal clinics and hospitals. These facilities produce ‘healthcare risk waste’ which must be managed responsibly, and it is the work of Environmental Health Practitioners working within municipalities to ensure that the waste produced by home-based care facilities is managed in line with legislation. This paper presents a case study of a twenty-seven-month expansive learning intervention in a South African municipality that sought to transform its healthcare risk waste management practices. Limited knowledge and inadequate knowledge-sharing practices were identified as the main hindrances to effective waste management. The practitioner-researcher facilitated a series of inter-agency, formative intervention workshops with municipal employees and Community Health Workers using the Developmental Work Research methodology. These workshops strengthened both groups of practitioners’ knowledge of the ‘who, how, what, why and when’ that underpins effective healthcare risk waste management, and enabled ‘boundary crossing’ for practitioners to work across their specialist areas towards co-defining and analysing problems and constructing new solutions.
- Full Text:
- Authors: Masilela, Priscilla , Olvitt, Lausanne L
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/372809 , vital:66624 , xlink:href="https://doi.org/10.1080/0158037X.2020.1717458"
- Description: Home-based care facilities provide basic healthcare services to people too sick or frail to access formal clinics and hospitals. These facilities produce ‘healthcare risk waste’ which must be managed responsibly, and it is the work of Environmental Health Practitioners working within municipalities to ensure that the waste produced by home-based care facilities is managed in line with legislation. This paper presents a case study of a twenty-seven-month expansive learning intervention in a South African municipality that sought to transform its healthcare risk waste management practices. Limited knowledge and inadequate knowledge-sharing practices were identified as the main hindrances to effective waste management. The practitioner-researcher facilitated a series of inter-agency, formative intervention workshops with municipal employees and Community Health Workers using the Developmental Work Research methodology. These workshops strengthened both groups of practitioners’ knowledge of the ‘who, how, what, why and when’ that underpins effective healthcare risk waste management, and enabled ‘boundary crossing’ for practitioners to work across their specialist areas towards co-defining and analysing problems and constructing new solutions.
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Transitions from rural contexts to and through higher education in South Africa: negotiating misrecognition
- Mgqwashu, Emmanuel M, Timmis, Sue, de Wet, Thea, Madondo, Nkosinathi Emmanuel
- Authors: Mgqwashu, Emmanuel M , Timmis, Sue , de Wet, Thea , Madondo, Nkosinathi Emmanuel
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148435 , vital:38739 , DOI:10.1080/03057925.2020.1763165
- Description: This paper reports on an international collaborative study that investigated how students from rural contexts negotiate the transition to university, and how prior cultural and educational experiences influence their higher education trajectories. A qualitative, participatory methodology was adopted, centred on co-researcher narratives, digital artefacts and discussions. Findings demonstrate how family and community, including religious, study, and self-help groups, influenced their transitions into higher education and journey through university and to their identities, agency and sense of belonging. The paper argues that university practices, values and norms need to acknowledge and incorporate all students’ prior experiences and histories and recognise their powerful contribution in working towards a decolonial higher education.
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- Authors: Mgqwashu, Emmanuel M , Timmis, Sue , de Wet, Thea , Madondo, Nkosinathi Emmanuel
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148435 , vital:38739 , DOI:10.1080/03057925.2020.1763165
- Description: This paper reports on an international collaborative study that investigated how students from rural contexts negotiate the transition to university, and how prior cultural and educational experiences influence their higher education trajectories. A qualitative, participatory methodology was adopted, centred on co-researcher narratives, digital artefacts and discussions. Findings demonstrate how family and community, including religious, study, and self-help groups, influenced their transitions into higher education and journey through university and to their identities, agency and sense of belonging. The paper argues that university practices, values and norms need to acknowledge and incorporate all students’ prior experiences and histories and recognise their powerful contribution in working towards a decolonial higher education.
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Transnational Crime in Deon Meyer’s Devil’s Peak and Santiago Gamboa’s Night Prayers:
- Authors: Naidu, Samantha
- Date: 2020
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/163881 , vital:41077 , ISBN 9783030534134 , https://0-doi.org.wam.seals.ac.za/10.1007/978-3-030-53413-4_2
- Description: Naidu argues that transnational crime wreaks havoc on global, national and personal levels in the postcolonial crime novels Devil’s Peak (2007) by South African author Deon Meyer and Night Prayers (2016) by Colombian author Santiago Gamboa. As postcolonial crime novels, they critique sociopolitical instability and corruption harking back to colonial times. Using mobility studies, Naidu interrogates the novels’ rendering of complex relations between the local and the global, and the past and the present. Despite stylistic and generic differences, both novels engage with the pervasive, transnational nature of criminal syndicates and current crimes which are a result of turbulent and unjust histories. Naidu examines the mobility of hapless victims, postcolonial anti-detectives and subversive heroines and comments on the ironic hope afforded by such figures.
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- Authors: Naidu, Samantha
- Date: 2020
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/163881 , vital:41077 , ISBN 9783030534134 , https://0-doi.org.wam.seals.ac.za/10.1007/978-3-030-53413-4_2
- Description: Naidu argues that transnational crime wreaks havoc on global, national and personal levels in the postcolonial crime novels Devil’s Peak (2007) by South African author Deon Meyer and Night Prayers (2016) by Colombian author Santiago Gamboa. As postcolonial crime novels, they critique sociopolitical instability and corruption harking back to colonial times. Using mobility studies, Naidu interrogates the novels’ rendering of complex relations between the local and the global, and the past and the present. Despite stylistic and generic differences, both novels engage with the pervasive, transnational nature of criminal syndicates and current crimes which are a result of turbulent and unjust histories. Naidu examines the mobility of hapless victims, postcolonial anti-detectives and subversive heroines and comments on the ironic hope afforded by such figures.
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Two new Caenis Species (Insecta: Ephemeroptera: Caenidae) from the Kruger National Park, South Africa:
- Malzacher, P, Barber-James, Helen M
- Authors: Malzacher, P , Barber-James, Helen M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150256 , vital:38954 , https://0-doi.org.wam.seals.ac.za/10.4001/003.028.0062
- Description: The new mayfly species Caenis albicans sp. n. and Caenis letabanensis sp. n. (Ephemeroptera: Caenidae) from the Kruger National Park, South Africa, are described herein. The new species were collected in the area of the confluence of the Olifants and Letaba Rivers. They belong to the Caenis – TPA group, a group widely distributed in Africa, characterised inter alia by forceps apically having a tuft of long spines. The material examined also contained samples from the Crocodile and Sabie Rivers, with larvae and imagines of Caenis brevipes Kimmins, 1956. The previously unknown larva of this species is also described.
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- Authors: Malzacher, P , Barber-James, Helen M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150256 , vital:38954 , https://0-doi.org.wam.seals.ac.za/10.4001/003.028.0062
- Description: The new mayfly species Caenis albicans sp. n. and Caenis letabanensis sp. n. (Ephemeroptera: Caenidae) from the Kruger National Park, South Africa, are described herein. The new species were collected in the area of the confluence of the Olifants and Letaba Rivers. They belong to the Caenis – TPA group, a group widely distributed in Africa, characterised inter alia by forceps apically having a tuft of long spines. The material examined also contained samples from the Crocodile and Sabie Rivers, with larvae and imagines of Caenis brevipes Kimmins, 1956. The previously unknown larva of this species is also described.
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Ukuchichimala kwechweba
- Authors: Mbungwana, Mthunzikzi
- Date: 2020
- Subjects: Xhosa poetry
- Language: Xhosa
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/168512 , vital:41590
- Description: iThisisi nepotifoliyo. It is a collection of poems relating to women and society and gender related issues including gender based violence. It also focuses on how Christianity and Xhosa culture has violated women's rights and how they both believe that men and women should have different roles in society.
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- Authors: Mbungwana, Mthunzikzi
- Date: 2020
- Subjects: Xhosa poetry
- Language: Xhosa
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/168512 , vital:41590
- Description: iThisisi nepotifoliyo. It is a collection of poems relating to women and society and gender related issues including gender based violence. It also focuses on how Christianity and Xhosa culture has violated women's rights and how they both believe that men and women should have different roles in society.
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Ukwowa mumwela nabangeli: transcendence, flight and inculturation in Zambian devotional artwork
- Authors: Mulenga, Aaron Samuel
- Date: 2020
- Subjects: Idols and images in art -- Zambia , Transcendence (Philosophy) in art , Christianity and culture -- Zambia , Flight in art , Christian art and symbolism -- Zambia , Representation (Philosophy) , Black people in art , Ethnicity in art , Group identity in art , Art and society -- Zambia , Yombwe, Laurence
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: http://hdl.handle.net/10962/146278 , vital:38511
- Description: With a focus on my artistic practice, this paper seeks to interrogate the tensions and overlaps in various representations of transcendence that have shaped my spirituality by interrogating how these have featured in Eurocentric Christian iconography and Zambian cultural practices, particularly cultural artefacts used for spiritual flight, housed in Zambian museums. Transcendence is understood by some as a change in a person’s physiological or psychological state that allows them to go beyond their experience of time, place or being. I understand transcendence to be the moment that one’s spirit is elevated beyond the limitations of their physical body. The use of Biblical text relating to flight will also be discussed as a comparative study to explore how transcendence through flight operates within Christianity and a Zambian cultural context. Furthermore, I shall interrogate how black artists (particularly Zambian), such as Laurence Yombwe, address the omission of black people from Christian iconography (which is predominantly depicted as white people). I aim to highlight the important role that representation plays in allowing for an individual to experience transcendence. I believe inculturation is a fitting solution to address some of the pitfalls in Christian iconography brought about due to the lack of representation of black people. Inculturation can be understood as an adaptation in the way the gospel of Jesus is preached to non-Christian cultures, and in turn, how these cultures influence the teachings of the gospel. Finally, I will explore how transcendence as a concept applies in my artworks and how the materials I use highlight this concept. Through my art, I grapple to combine what seem like disparate spiritual paradigms, arising from my culture and my faith. My artwork seeks to contribute to the work that particular artists (a majority of them black) are grappling with to correct the lack of representation of black people in Christian iconography. I will use the notion of inculturation as an avenue through which to interrogate the tensions I experience while exploring the concept of transcendence.
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- Authors: Mulenga, Aaron Samuel
- Date: 2020
- Subjects: Idols and images in art -- Zambia , Transcendence (Philosophy) in art , Christianity and culture -- Zambia , Flight in art , Christian art and symbolism -- Zambia , Representation (Philosophy) , Black people in art , Ethnicity in art , Group identity in art , Art and society -- Zambia , Yombwe, Laurence
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: http://hdl.handle.net/10962/146278 , vital:38511
- Description: With a focus on my artistic practice, this paper seeks to interrogate the tensions and overlaps in various representations of transcendence that have shaped my spirituality by interrogating how these have featured in Eurocentric Christian iconography and Zambian cultural practices, particularly cultural artefacts used for spiritual flight, housed in Zambian museums. Transcendence is understood by some as a change in a person’s physiological or psychological state that allows them to go beyond their experience of time, place or being. I understand transcendence to be the moment that one’s spirit is elevated beyond the limitations of their physical body. The use of Biblical text relating to flight will also be discussed as a comparative study to explore how transcendence through flight operates within Christianity and a Zambian cultural context. Furthermore, I shall interrogate how black artists (particularly Zambian), such as Laurence Yombwe, address the omission of black people from Christian iconography (which is predominantly depicted as white people). I aim to highlight the important role that representation plays in allowing for an individual to experience transcendence. I believe inculturation is a fitting solution to address some of the pitfalls in Christian iconography brought about due to the lack of representation of black people. Inculturation can be understood as an adaptation in the way the gospel of Jesus is preached to non-Christian cultures, and in turn, how these cultures influence the teachings of the gospel. Finally, I will explore how transcendence as a concept applies in my artworks and how the materials I use highlight this concept. Through my art, I grapple to combine what seem like disparate spiritual paradigms, arising from my culture and my faith. My artwork seeks to contribute to the work that particular artists (a majority of them black) are grappling with to correct the lack of representation of black people in Christian iconography. I will use the notion of inculturation as an avenue through which to interrogate the tensions I experience while exploring the concept of transcendence.
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