The effects of selected samples on the bio-stimulatory capacity and anti-aging effects of red light on human skin cells
- Authors: Rudolph, Carlen
- Date: 2024-04
- Subjects: Cell culture -- Technique , Dermatologic agents , Collagen , Biochemistry -- Technique
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/64347 , vital:73677
- Description: Photobiomodulation (PBM) has gained a remarkable interest in the cosmeceutical industry, with research demonstrating supporting evidence for its use as anti-aging and skin-rejuvenating strategies. It is defined as photons at a non-thermal irradiance or non-ionizing photonic energy that trigger photochemical changes within the cellular structure to alter certain biological activities. Lasers were the main focus during the developmental years of light-based treatments, but since the introduction of non-ablative, light-emitting diode (LED) devices, the focus has changed because of the reduced concerns associated with lasers, such as costs, ablation cutting, thermally coagulating tissue, no downtime needed after treatment, and no trained staff needed for operation. The precise biochemical mechanism for PBM is still to be elucidated; however, accepted theories suggest that it has an influence on the activity of cytochrome c oxidase, a complex located in the electron transport chain, or on the viscosity of the interfacial water layer (IWL) of the mitochondrial membrane. The interaction of those cellular components with the light then leads to the primary responses of increased ROS, ATP production, and intracellular calcium, which ultimately leads to the stimulation of secondary responses that are desired for skin rejuvenation and anti-aging, such as cell proliferation and collagen production. There is controversy surrounding photobiomodulation (PBM), mostly because of the incomplete understanding behind its biochemical mechanism and the number of parameters that require optimization; however, it still poses as a promising field for research into anti-aging properties, as seen in the literature. Besides the use of devices for skin rejuvenation and anti-aging strategies, it is not uncommon to see plant extracts and other natural products being used in current skin care products for the same reason? This is mostly because of their promising bioactivities, some of which include antioxidant, anti-inflammatory, anti-bacterial, collagen-stimulating, and cell-proliferating activities. The aim of this study was to investigate the bio-stimulatory capacity of red light on skin cells and to evaluate possible effects it could have in combination with samples that already show promising anti-aging properties in research. The samples that were selected for this study are: Aspalathus linearis (rooibos) unfermented extract, L-ascorbic acid 2-phosphate, mangrove bee honey, stingless bee honey, Sargassum oligocystum (brown seaweed) and Ulva fasciata (green seaweed).It was found that red light irradiation did indeed stimulate the primary responses of ROS, ATP production, and intracellular calcium levels in HaCaT keratinocytes, as proposed in the hypothesised theory. However, none of the proposed secondary responses to cell proliferation or collagen production were demonstrated. In fact, the opposite was observed for cell proliferation and collagen production, where red light irradiation seemed to be cytostatic towards Hs27 fibroblast cells and caused significant decreases in collagen production. Red light energy dosages of 10, 20 and 30 J/cm2, yielded different primary responses with 20 and 30 J/cm2 generally causing more significant stimulation than that of 10 J/cm2. It should also be noted that even if the desired secondary responses were not observed in this study, it does not mean that red light does not have the capacity to still stimulate them. It is clear that the responses are energy dosage-dependent, and it is suggested that lower energy dosages could possibly lead to cell proliferation and that longer incubation periods post-irradiation are required before measuring the endpoint of collagen production. For the combination of red light irradiation and selected test samples, it was demonstrated that the order of samples that yielded the best outcomes is: stingless bee honey > mangrove bee honey > U. fasciata > S. oligocystum > 2-PAA > green rooibos. Unexpected results were demonstrated for green rooibos in the presence and absence of red light, which included decreased ATP production and collagen biosynthesis. Further investigation is therefore needed to have a better understanding of these unanticipated results. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-04
- Authors: Rudolph, Carlen
- Date: 2024-04
- Subjects: Cell culture -- Technique , Dermatologic agents , Collagen , Biochemistry -- Technique
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/64347 , vital:73677
- Description: Photobiomodulation (PBM) has gained a remarkable interest in the cosmeceutical industry, with research demonstrating supporting evidence for its use as anti-aging and skin-rejuvenating strategies. It is defined as photons at a non-thermal irradiance or non-ionizing photonic energy that trigger photochemical changes within the cellular structure to alter certain biological activities. Lasers were the main focus during the developmental years of light-based treatments, but since the introduction of non-ablative, light-emitting diode (LED) devices, the focus has changed because of the reduced concerns associated with lasers, such as costs, ablation cutting, thermally coagulating tissue, no downtime needed after treatment, and no trained staff needed for operation. The precise biochemical mechanism for PBM is still to be elucidated; however, accepted theories suggest that it has an influence on the activity of cytochrome c oxidase, a complex located in the electron transport chain, or on the viscosity of the interfacial water layer (IWL) of the mitochondrial membrane. The interaction of those cellular components with the light then leads to the primary responses of increased ROS, ATP production, and intracellular calcium, which ultimately leads to the stimulation of secondary responses that are desired for skin rejuvenation and anti-aging, such as cell proliferation and collagen production. There is controversy surrounding photobiomodulation (PBM), mostly because of the incomplete understanding behind its biochemical mechanism and the number of parameters that require optimization; however, it still poses as a promising field for research into anti-aging properties, as seen in the literature. Besides the use of devices for skin rejuvenation and anti-aging strategies, it is not uncommon to see plant extracts and other natural products being used in current skin care products for the same reason? This is mostly because of their promising bioactivities, some of which include antioxidant, anti-inflammatory, anti-bacterial, collagen-stimulating, and cell-proliferating activities. The aim of this study was to investigate the bio-stimulatory capacity of red light on skin cells and to evaluate possible effects it could have in combination with samples that already show promising anti-aging properties in research. The samples that were selected for this study are: Aspalathus linearis (rooibos) unfermented extract, L-ascorbic acid 2-phosphate, mangrove bee honey, stingless bee honey, Sargassum oligocystum (brown seaweed) and Ulva fasciata (green seaweed).It was found that red light irradiation did indeed stimulate the primary responses of ROS, ATP production, and intracellular calcium levels in HaCaT keratinocytes, as proposed in the hypothesised theory. However, none of the proposed secondary responses to cell proliferation or collagen production were demonstrated. In fact, the opposite was observed for cell proliferation and collagen production, where red light irradiation seemed to be cytostatic towards Hs27 fibroblast cells and caused significant decreases in collagen production. Red light energy dosages of 10, 20 and 30 J/cm2, yielded different primary responses with 20 and 30 J/cm2 generally causing more significant stimulation than that of 10 J/cm2. It should also be noted that even if the desired secondary responses were not observed in this study, it does not mean that red light does not have the capacity to still stimulate them. It is clear that the responses are energy dosage-dependent, and it is suggested that lower energy dosages could possibly lead to cell proliferation and that longer incubation periods post-irradiation are required before measuring the endpoint of collagen production. For the combination of red light irradiation and selected test samples, it was demonstrated that the order of samples that yielded the best outcomes is: stingless bee honey > mangrove bee honey > U. fasciata > S. oligocystum > 2-PAA > green rooibos. Unexpected results were demonstrated for green rooibos in the presence and absence of red light, which included decreased ATP production and collagen biosynthesis. Further investigation is therefore needed to have a better understanding of these unanticipated results. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-04
Integrating state-space modelling and systematic conservation planning to recommend penguin-fishery management zones in Algoa Bay, South Africa
- Stockdale, Victoria, Goodall, Victoria, Clifford-Holmes, Jia
- Authors: Stockdale, Victoria , Goodall, Victoria , Clifford-Holmes, Jia
- Date: 2023-12
- Subjects: Biodiversity conservation -- South Africa -- Port Elizabeth , Natural resource conservation , Marine ecology
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/62611 , vital:72828
- Description: Direct anthropogenic impacts on vulnerable marine ecosystems are growing and require effective conservation measures. Integrating the cost impacts of conservation interventions and optimising the spatiotemporal scale of management interventions may improve cohesion between opposing marine users. This study aimed to integrate spatial and temporal models to advise dynamic penguin-fishery management plans in Algoa Bay, off Gqeberha, South Africa, that would maximise penguin foraging success while minimising the impact on the fishing industry. Determining the foraging locations important to breeding penguins is fundamental when understanding the relationship between fisheries and prey availability. Using Global Positioning System (GPS) data gathered from feeding trips of breeding African penguins between 2012 and 2017, and a hidden Markov model, three behavioural states (foraging, commuting, transitioning) were inferred and used as conservation targets in spatial prioritisation using the prioritizr package in R. The cost to the fishery was estimated using the catch of pelagic fish by the fishing industry between 2012 and 2015 as the proxy. The energetic cost to penguins was the distance they travelled from their breeding colony. Nine prioritisation scenarios, varying in levels of conservation for penguins, spatial cohesion and costs to fisheries, were developed using all year’s combined data to explore an ‘optimal’ closure configuration. The optimal closure was determined as an area which met the targets for penguin conservation, with a low cost to the fishery, close to the breeding colony and spatially clumped. The best solution from each scenario was isolated and the solution for the conservation target of 20% foraging habitat, 10% commuting habitat and 10% transitioning habitat and a boundary penalty of 0.01 (a dimensionless value that is used to reduce spatial fragmentation – increasing the value of the parameter signals that it is important to minimise the total exposed boundary of the prioritisation by favouring solutions where units are clumped together) was chosen as the optimal closure. This configuration was used as a static closure and applied to individual fishing seasons to estimate how the cost of a static closure design to the fishery would vary between seasons. Subsequently, a dynamic closure was designed using the same optimal configuration criteria every year, and the cost to the fishing industry was compared seasonally with the cost of a static closure. The cost to fisheries of dynamic closures was consistently lower than that of a static closure and the area required to meet the penguin feeding targets was drastically reduced. While dynamic closure scenarios show promise to minimise costs to the industry while meeting penguin conservation targets, these configurations were designed retrospectively with data collected after the end of the fishery seasons. For efficient management, the closures need to be designed by using data collected at an appropriate temporal scale. For that, the critical missing dimension to this study is the addition of real-time data on pelagic fish positions, areas of fishing intensity and sites of penguin foraging to create appropriate recommendations for up-to-date fishery exclusion zones. Therefore, the priority now is to explore methods of collecting real-time data on pelagic fish abundance, feeding behaviour of penguins at sea, site and mass of pelagic fishery catch, and using these data to delineate real-time, dynamic closures, coupled with a governance and management strategy that can implement dynamic closures. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2023
- Full Text:
- Date Issued: 2023-12
- Authors: Stockdale, Victoria , Goodall, Victoria , Clifford-Holmes, Jia
- Date: 2023-12
- Subjects: Biodiversity conservation -- South Africa -- Port Elizabeth , Natural resource conservation , Marine ecology
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/62611 , vital:72828
- Description: Direct anthropogenic impacts on vulnerable marine ecosystems are growing and require effective conservation measures. Integrating the cost impacts of conservation interventions and optimising the spatiotemporal scale of management interventions may improve cohesion between opposing marine users. This study aimed to integrate spatial and temporal models to advise dynamic penguin-fishery management plans in Algoa Bay, off Gqeberha, South Africa, that would maximise penguin foraging success while minimising the impact on the fishing industry. Determining the foraging locations important to breeding penguins is fundamental when understanding the relationship between fisheries and prey availability. Using Global Positioning System (GPS) data gathered from feeding trips of breeding African penguins between 2012 and 2017, and a hidden Markov model, three behavioural states (foraging, commuting, transitioning) were inferred and used as conservation targets in spatial prioritisation using the prioritizr package in R. The cost to the fishery was estimated using the catch of pelagic fish by the fishing industry between 2012 and 2015 as the proxy. The energetic cost to penguins was the distance they travelled from their breeding colony. Nine prioritisation scenarios, varying in levels of conservation for penguins, spatial cohesion and costs to fisheries, were developed using all year’s combined data to explore an ‘optimal’ closure configuration. The optimal closure was determined as an area which met the targets for penguin conservation, with a low cost to the fishery, close to the breeding colony and spatially clumped. The best solution from each scenario was isolated and the solution for the conservation target of 20% foraging habitat, 10% commuting habitat and 10% transitioning habitat and a boundary penalty of 0.01 (a dimensionless value that is used to reduce spatial fragmentation – increasing the value of the parameter signals that it is important to minimise the total exposed boundary of the prioritisation by favouring solutions where units are clumped together) was chosen as the optimal closure. This configuration was used as a static closure and applied to individual fishing seasons to estimate how the cost of a static closure design to the fishery would vary between seasons. Subsequently, a dynamic closure was designed using the same optimal configuration criteria every year, and the cost to the fishing industry was compared seasonally with the cost of a static closure. The cost to fisheries of dynamic closures was consistently lower than that of a static closure and the area required to meet the penguin feeding targets was drastically reduced. While dynamic closure scenarios show promise to minimise costs to the industry while meeting penguin conservation targets, these configurations were designed retrospectively with data collected after the end of the fishery seasons. For efficient management, the closures need to be designed by using data collected at an appropriate temporal scale. For that, the critical missing dimension to this study is the addition of real-time data on pelagic fish positions, areas of fishing intensity and sites of penguin foraging to create appropriate recommendations for up-to-date fishery exclusion zones. Therefore, the priority now is to explore methods of collecting real-time data on pelagic fish abundance, feeding behaviour of penguins at sea, site and mass of pelagic fishery catch, and using these data to delineate real-time, dynamic closures, coupled with a governance and management strategy that can implement dynamic closures. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2023
- Full Text:
- Date Issued: 2023-12
A council of women
- Authors: Sobekwa, Lelethu Anathi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435988 , vital:73218
- Description: This thesis comprises extracts of life writing written in short prose forms. The work reads like a novella and I have been inspired by Margaret Patton Chapman’s approach to the novella, where she condenses “the telling of a long story time wise”, so that a story occurring over two years can be told over two pages. The thesis explores relationships between mother, daughter, grandmother and granddaughter, each with different life experiences and each teaching the next generation about how to navigate life as politically, socially and economically disadvantaged women. I have also drawn inspiration from authors such as NoViolet Bulawayo who explores the hypocrisies of the church and the government in We Need New Names. In Kate Bernheimer’s “Fairy Tale is Form, Form is Fairy Tale” she writes about fairy tales adopting “intuitive logic” or telling in the form of “this happens and then this happens” while the explanation behind the events is not spelt out but rather exists between the lines. My thesis adopts this style of writing by allowing the reader to understand what is being said without over-simplifying. To this end, I have used the concept of place modelled on Es’kia Mphahlele’s In Corner B, where characters are inscribed in relation to the spaces they inhabit. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Sobekwa, Lelethu Anathi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435988 , vital:73218
- Description: This thesis comprises extracts of life writing written in short prose forms. The work reads like a novella and I have been inspired by Margaret Patton Chapman’s approach to the novella, where she condenses “the telling of a long story time wise”, so that a story occurring over two years can be told over two pages. The thesis explores relationships between mother, daughter, grandmother and granddaughter, each with different life experiences and each teaching the next generation about how to navigate life as politically, socially and economically disadvantaged women. I have also drawn inspiration from authors such as NoViolet Bulawayo who explores the hypocrisies of the church and the government in We Need New Names. In Kate Bernheimer’s “Fairy Tale is Form, Form is Fairy Tale” she writes about fairy tales adopting “intuitive logic” or telling in the form of “this happens and then this happens” while the explanation behind the events is not spelt out but rather exists between the lines. My thesis adopts this style of writing by allowing the reader to understand what is being said without over-simplifying. To this end, I have used the concept of place modelled on Es’kia Mphahlele’s In Corner B, where characters are inscribed in relation to the spaces they inhabit. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2023
- Full Text:
- Date Issued: 2023-10-13
Identification of novel Arf1 GTPase inhibitors for cancer target validation
- Authors: Mqwathi, Nomxolisi Vuyokasi
- Date: 2023-10-13
- Subjects: ARF1 , GTPase , Guanosine triphosphatase , Cancer Treatment
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424666 , vital:72173
- Description: The key regulators of both anterograde and retrograde vesicular traffic, adenosine diphosphate-ribosylation factors (Arfs), also coordinate various signalling pathways and regulate cellular processes required for cell survival and function. In addition to its role in mediating secretory trafficking in the Golgi apparatus, the involvement of Arf1 in signalling pathways that contribute to the formation and progression of cancer has become apparent, and the overexpression and deregulation of Arf1 activity has been associated with cancer cell invasion, proliferation and metastasis. As with other small GTPases, Arf1 must cycle back and forth between an inactive (GDP-bound) and active (GTP-bound) conformation to carry out its function. However, the cycle of Arf1 inactivation and activation is controlled by Arf GTPase activating proteins (Arf-GAPs) that stimulate Arf1 to hydrolyse the bound GTP to GDP and Arf guanine nucleotide exchange factors (Arf-GEFs) that facilitate GDP for GTP exchange on Arf1, respectively. The identification of Arf1 inhibitors that indirectly disrupt Arf1 function by blocking its interaction with Arf-GAPs or Arf-GEFs has generated interest in their use as possible anti-cancer agents. The suppression of Arf1 activation (by targeting Arf-GEFs) has been investigated as a potential cancer therapeutic target and resulted in inhibitor compounds that have micromolar-range activity against cancer cells and targets and promising results in mouse models, but experience problems with bioavailability when used in vivo. This motivates the search for novel Arf1 inhibitors for validation purposes to question whether Arf1 is a viable target for cancer therapy. The purpose of the study was to employ a recently developed colourimetric screening assay to identify inhibitors of Arf1 activation (Arf-GEF inhibitors) and deactivation (Arf-GAP inhibitors), with a focus on evaluating the potential of Arf1 deactivation as an entirely novel anti-cancer target. The proteins required for the assay (Arf1, Arf-GEF and -GAP domains and a reporter protein, GST-GGA3) were expressed in E. coli. and purified using affinity chromatography. The assay could detect the activation of Arf1 by the catalytic Sec7 domain of the three Arf-GEFs chosen for this study, but reproducibility was compromised by the occasional spontaneous activation of Arf1 in the absence of the Arf-GEFs. By contrast, the assay could reproducibly detect Arf1 deactivation by an Arf-GAP domain (Arf-GAP1GAP) and was subsequently used to screen a library of α-helix mimetics. Thirteen hit compounds with IC50 values ranging from 0.53 to 20.95 μM were found to inhibit Arf-GAP1GAP-mediated stimulation of GTP hydrolysis by Arf1-GTP in this assay format, however, they did not effectively suppress the proliferation of three tested cell lines (HeLa, MCF-7 and MCF-12A). Interestingly, the results obtained from fluorescence microscopy studies suggested that the compounds disrupt Golgi structure and Arf1 localisation, presumably by keeping Arf1 in its active conformation by blocking Arf-GAP1 function. This suggests that the compounds affect Arf1 function in cells, and may be used to explore the feasibility of targeting Arf1 deactivation for anti-cancer purposes in a wider range of cell lines and experiments. It has been reported that Arf-GAP1 inhibition is associated with the suppression of cell migration, and the potential of the compounds as metastasis inhibitors may also be explored. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mqwathi, Nomxolisi Vuyokasi
- Date: 2023-10-13
- Subjects: ARF1 , GTPase , Guanosine triphosphatase , Cancer Treatment
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424666 , vital:72173
- Description: The key regulators of both anterograde and retrograde vesicular traffic, adenosine diphosphate-ribosylation factors (Arfs), also coordinate various signalling pathways and regulate cellular processes required for cell survival and function. In addition to its role in mediating secretory trafficking in the Golgi apparatus, the involvement of Arf1 in signalling pathways that contribute to the formation and progression of cancer has become apparent, and the overexpression and deregulation of Arf1 activity has been associated with cancer cell invasion, proliferation and metastasis. As with other small GTPases, Arf1 must cycle back and forth between an inactive (GDP-bound) and active (GTP-bound) conformation to carry out its function. However, the cycle of Arf1 inactivation and activation is controlled by Arf GTPase activating proteins (Arf-GAPs) that stimulate Arf1 to hydrolyse the bound GTP to GDP and Arf guanine nucleotide exchange factors (Arf-GEFs) that facilitate GDP for GTP exchange on Arf1, respectively. The identification of Arf1 inhibitors that indirectly disrupt Arf1 function by blocking its interaction with Arf-GAPs or Arf-GEFs has generated interest in their use as possible anti-cancer agents. The suppression of Arf1 activation (by targeting Arf-GEFs) has been investigated as a potential cancer therapeutic target and resulted in inhibitor compounds that have micromolar-range activity against cancer cells and targets and promising results in mouse models, but experience problems with bioavailability when used in vivo. This motivates the search for novel Arf1 inhibitors for validation purposes to question whether Arf1 is a viable target for cancer therapy. The purpose of the study was to employ a recently developed colourimetric screening assay to identify inhibitors of Arf1 activation (Arf-GEF inhibitors) and deactivation (Arf-GAP inhibitors), with a focus on evaluating the potential of Arf1 deactivation as an entirely novel anti-cancer target. The proteins required for the assay (Arf1, Arf-GEF and -GAP domains and a reporter protein, GST-GGA3) were expressed in E. coli. and purified using affinity chromatography. The assay could detect the activation of Arf1 by the catalytic Sec7 domain of the three Arf-GEFs chosen for this study, but reproducibility was compromised by the occasional spontaneous activation of Arf1 in the absence of the Arf-GEFs. By contrast, the assay could reproducibly detect Arf1 deactivation by an Arf-GAP domain (Arf-GAP1GAP) and was subsequently used to screen a library of α-helix mimetics. Thirteen hit compounds with IC50 values ranging from 0.53 to 20.95 μM were found to inhibit Arf-GAP1GAP-mediated stimulation of GTP hydrolysis by Arf1-GTP in this assay format, however, they did not effectively suppress the proliferation of three tested cell lines (HeLa, MCF-7 and MCF-12A). Interestingly, the results obtained from fluorescence microscopy studies suggested that the compounds disrupt Golgi structure and Arf1 localisation, presumably by keeping Arf1 in its active conformation by blocking Arf-GAP1 function. This suggests that the compounds affect Arf1 function in cells, and may be used to explore the feasibility of targeting Arf1 deactivation for anti-cancer purposes in a wider range of cell lines and experiments. It has been reported that Arf-GAP1 inhibition is associated with the suppression of cell migration, and the potential of the compounds as metastasis inhibitors may also be explored. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2023
- Full Text:
- Date Issued: 2023-10-13
Patterns of inclusion and exclusion among trans women in South Africa: a critical narrative inquiry
- Authors: Shabalala, Siyanda Buyile
- Date: 2023-03-30
- Subjects: Transgender women South Africa , Genderism , Social inclusion , Social integration , Social exclusion , Social isolation , Narrative
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/408874 , vital:70533
- Description: Trans women have for the most part remained grossly marginalised in gender development frameworks that have concerned themselves with resolving the historical disenfranchisement of women in patriarchal societies. Considering this continuing systemic erasure of trans subjectivity, this study has aimed to foreground transness, engaging trans women’s experiences of inclusion and exclusion to better understand the traditionally oppressive institutionality of gender in South Africa from a historically silenced trans standpoint. Semi-structured individual interviews were conducted with five trans women living in South Africa. Data was transcribed and analysed using narrative analysis. Mapping the structures, practices and norms that contribute to the marginalisation of trans women in South Africa, the study found that trans women face economic vulnerability driven by familial rejection along with structural discrimination in a gender-biased labour system. Furthermore, trans women were revealed to contend with institutional erasure and stigmatisation in sex-segregated healthcare structures as well as invisibilisation in cisnormative South African knowledge systems that underrepresent trans identities and their viewpoints of the world. Underlyingly, the societal exclusion of trans women emerged as centrally organised by a structure of genderism that rigidly assumes the binariness and fixedness of gender, principally in ways that restrict trans women's right to self-determine as women. Genderism was observed to collude with factors of race and class in a largely capitalist post-apartheid South African society, working concurrently and jointly to reinforce the social exclusion of trans women. However, often subtle narratives of trans social inclusion located marginalising cisgender power in South African democracy as contested terrain. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-03-30
- Authors: Shabalala, Siyanda Buyile
- Date: 2023-03-30
- Subjects: Transgender women South Africa , Genderism , Social inclusion , Social integration , Social exclusion , Social isolation , Narrative
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/408874 , vital:70533
- Description: Trans women have for the most part remained grossly marginalised in gender development frameworks that have concerned themselves with resolving the historical disenfranchisement of women in patriarchal societies. Considering this continuing systemic erasure of trans subjectivity, this study has aimed to foreground transness, engaging trans women’s experiences of inclusion and exclusion to better understand the traditionally oppressive institutionality of gender in South Africa from a historically silenced trans standpoint. Semi-structured individual interviews were conducted with five trans women living in South Africa. Data was transcribed and analysed using narrative analysis. Mapping the structures, practices and norms that contribute to the marginalisation of trans women in South Africa, the study found that trans women face economic vulnerability driven by familial rejection along with structural discrimination in a gender-biased labour system. Furthermore, trans women were revealed to contend with institutional erasure and stigmatisation in sex-segregated healthcare structures as well as invisibilisation in cisnormative South African knowledge systems that underrepresent trans identities and their viewpoints of the world. Underlyingly, the societal exclusion of trans women emerged as centrally organised by a structure of genderism that rigidly assumes the binariness and fixedness of gender, principally in ways that restrict trans women's right to self-determine as women. Genderism was observed to collude with factors of race and class in a largely capitalist post-apartheid South African society, working concurrently and jointly to reinforce the social exclusion of trans women. However, often subtle narratives of trans social inclusion located marginalising cisgender power in South African democracy as contested terrain. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-03-30
An investigation of traveling ionospheric disturbances (TIDs) in the SANAE HF radar data
- Authors: Atilaw, Tsige Yared
- Date: 2022-04-07
- Subjects: Ionospheric storms Antarctica , Radar Antarctica , Range time-intensity (RTI) , South African National Antarctic Expedition (SANAE) , Super Dual Auroral Radar Network (SuperDARN)
- Language: English
- Type: Doctoral thesis , text
- Identifier: http://hdl.handle.net/10962/232377 , vital:49986 , DOI 10.21504/10962/232377
- Description: This thesis aims to study the characteristics of traveling ionospheric disturbances (TIDs) as identified in the radar data of the South African National Antarctic Expedition (SANAE) Super Dual Auroral Radar Network (SuperDARN) radar located in Antarctica. For this project, 22 TIDs were identified from visual inspection of range time-intensity (RTI) plots of backscattered power and Doppler velocity parameters of the SANAE radar between 2005âAS2015. These events were studied to determine their characteristics and driving mechanisms. Where good quality data were available, the SANAE HF radar data were supplemented by Halley radar data, which has large area of overlapping field of view (FOV) with the SANAE radar, and also by GPS TEC data. This provided a multi-instrument data analysis of some TID events. Different spectral analysis methods, namely the multitaper method (MTM), Fast Fourier transform (FFT) and the Lomb-Scargle periodogram were used to obtain spectral information of the observed waves. The advantage of using multiple windowing in MTM over the traditional windowing method was illustrated using one of the TID events. In addition, the analytic signal of the wave from the MTM method was used to estimate the instantaneous phase velocity and propagation azimuth of the wave, which was able to track the change in the characteristics of the medium-scale TID (MSTID) efficiently throughout the duration of the event. This is a clear advantage over other windowing techniques. The energy contribution by this MSTID through Joule heating was estimated over the region where spectral analysis of both SANAE and Halley data showed it to be present. The majority of the TIDs (65.4%) could be classified as MSTIDs with periods of 20–60 minutes, velocities of 50–333 ms1 and wavelengths of 129–833 km. The TID occurrence rate was high around the March equinox with 12 out of the 16 event days being during March–May. March had a particularly high number of occurrences of TIDs (46%). The majority of the TIDs observed during this month propagated northward or southeastward. In terms of prevailing geomagnetic conditions, 6 out of 16 event days were geomagnetically quiet, while 10 occurred during geomagnetic storms and substorms. During quiet conditions, TIDs could be linked to Es and polarised electric fields in 2 of these events. The other quiet time events could not be related to Es instability and polarised electric field either because their exact propagation direction could not be determined or data quality from the Es region scatter was too poor to perform spectral analysis. The storm-/substorm-related TIDs are possibly generated through Joule heating, the Lorentz force and energetic particle precipitation. , Thesis (PhD) -- Faculty of Science, Physics and Electronics, 2022
- Full Text:
- Date Issued: 2022-04-07
- Authors: Atilaw, Tsige Yared
- Date: 2022-04-07
- Subjects: Ionospheric storms Antarctica , Radar Antarctica , Range time-intensity (RTI) , South African National Antarctic Expedition (SANAE) , Super Dual Auroral Radar Network (SuperDARN)
- Language: English
- Type: Doctoral thesis , text
- Identifier: http://hdl.handle.net/10962/232377 , vital:49986 , DOI 10.21504/10962/232377
- Description: This thesis aims to study the characteristics of traveling ionospheric disturbances (TIDs) as identified in the radar data of the South African National Antarctic Expedition (SANAE) Super Dual Auroral Radar Network (SuperDARN) radar located in Antarctica. For this project, 22 TIDs were identified from visual inspection of range time-intensity (RTI) plots of backscattered power and Doppler velocity parameters of the SANAE radar between 2005âAS2015. These events were studied to determine their characteristics and driving mechanisms. Where good quality data were available, the SANAE HF radar data were supplemented by Halley radar data, which has large area of overlapping field of view (FOV) with the SANAE radar, and also by GPS TEC data. This provided a multi-instrument data analysis of some TID events. Different spectral analysis methods, namely the multitaper method (MTM), Fast Fourier transform (FFT) and the Lomb-Scargle periodogram were used to obtain spectral information of the observed waves. The advantage of using multiple windowing in MTM over the traditional windowing method was illustrated using one of the TID events. In addition, the analytic signal of the wave from the MTM method was used to estimate the instantaneous phase velocity and propagation azimuth of the wave, which was able to track the change in the characteristics of the medium-scale TID (MSTID) efficiently throughout the duration of the event. This is a clear advantage over other windowing techniques. The energy contribution by this MSTID through Joule heating was estimated over the region where spectral analysis of both SANAE and Halley data showed it to be present. The majority of the TIDs (65.4%) could be classified as MSTIDs with periods of 20–60 minutes, velocities of 50–333 ms1 and wavelengths of 129–833 km. The TID occurrence rate was high around the March equinox with 12 out of the 16 event days being during March–May. March had a particularly high number of occurrences of TIDs (46%). The majority of the TIDs observed during this month propagated northward or southeastward. In terms of prevailing geomagnetic conditions, 6 out of 16 event days were geomagnetically quiet, while 10 occurred during geomagnetic storms and substorms. During quiet conditions, TIDs could be linked to Es and polarised electric fields in 2 of these events. The other quiet time events could not be related to Es instability and polarised electric field either because their exact propagation direction could not be determined or data quality from the Es region scatter was too poor to perform spectral analysis. The storm-/substorm-related TIDs are possibly generated through Joule heating, the Lorentz force and energetic particle precipitation. , Thesis (PhD) -- Faculty of Science, Physics and Electronics, 2022
- Full Text:
- Date Issued: 2022-04-07
Praying mantis
- Authors: Kenene, Thobeka
- Date: 2022-04-07
- Subjects: Creative writing (Higher education) South Africa , Diaries -- Authorship , South African fiction (English) 21st century , South African essays (English) 21st century , Portuguese fiction 20th century History and criticism , Russian fiction 20th century History and criticism , Zimbabwean fiction (English) 20th century History and criticism , American fiction 20th century History and criticism
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/292726 , vital:57010
- Description: (Prologue) I could only see in black and white as if I had travelled through time. I was the star of the medieval people who waited on me. The city was Johannesburg where strange faces called me a traitor because I was an educated black person. I hid between the skyscrapers and ran into a mirror image of myself as a man. “I write this book,” he said to his readers, “To invoke a yearning in our youth to awaken from slumber. To set examples for them to desist from characters like Velesazi and Nongendi, and imitate Nomsa and Themba. And also, to contribute to Xhosa literature.” He signed off by calling himself our servant. These are the words from the note my great-grandfather left me. We walked together across a barren field and past a graveyard. I was feeling tired and lost; I wanted to get home as fast as possible. We quickened our step and entered a church site. Inside the church were all my close relatives. I saw myself on stage looking down at them, and when I opened my mouth to sing, they began laughing at me. I imagined him in his 1917 suit, as a writer, penning down his first novel that is dedicated to his mother. His round cheeks enveloped in a haze of candle light. He visited my dream in 2012 and in the dream he asked me, “Do you see?” I said, “Yes, I see.” My great-grandfather hummed a song from his belly. I inhaled deeply into my belly and then exhaled a sound. Together we hummed this song that made everyone fall silent and listen. In the dream I could feel my lungs expanding and deflating along to the rhythm of the song. As my great-grandfather and I sang it, the night lamps shone brighter. I had become my great-grandfather, wearing his suit and black leather shoes. His friends were my friends. They turned and asked me what my clan name was. When I told them, they whispered something among themselves. One of them said to me, “Unogcwabevu.” I saw a white unknown woman who was afraid of me. I told her it is going to be okay, and that I would not harm her. But the colour of my skin frightened her. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
- Full Text:
- Date Issued: 2022-04-07
- Authors: Kenene, Thobeka
- Date: 2022-04-07
- Subjects: Creative writing (Higher education) South Africa , Diaries -- Authorship , South African fiction (English) 21st century , South African essays (English) 21st century , Portuguese fiction 20th century History and criticism , Russian fiction 20th century History and criticism , Zimbabwean fiction (English) 20th century History and criticism , American fiction 20th century History and criticism
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/292726 , vital:57010
- Description: (Prologue) I could only see in black and white as if I had travelled through time. I was the star of the medieval people who waited on me. The city was Johannesburg where strange faces called me a traitor because I was an educated black person. I hid between the skyscrapers and ran into a mirror image of myself as a man. “I write this book,” he said to his readers, “To invoke a yearning in our youth to awaken from slumber. To set examples for them to desist from characters like Velesazi and Nongendi, and imitate Nomsa and Themba. And also, to contribute to Xhosa literature.” He signed off by calling himself our servant. These are the words from the note my great-grandfather left me. We walked together across a barren field and past a graveyard. I was feeling tired and lost; I wanted to get home as fast as possible. We quickened our step and entered a church site. Inside the church were all my close relatives. I saw myself on stage looking down at them, and when I opened my mouth to sing, they began laughing at me. I imagined him in his 1917 suit, as a writer, penning down his first novel that is dedicated to his mother. His round cheeks enveloped in a haze of candle light. He visited my dream in 2012 and in the dream he asked me, “Do you see?” I said, “Yes, I see.” My great-grandfather hummed a song from his belly. I inhaled deeply into my belly and then exhaled a sound. Together we hummed this song that made everyone fall silent and listen. In the dream I could feel my lungs expanding and deflating along to the rhythm of the song. As my great-grandfather and I sang it, the night lamps shone brighter. I had become my great-grandfather, wearing his suit and black leather shoes. His friends were my friends. They turned and asked me what my clan name was. When I told them, they whispered something among themselves. One of them said to me, “Unogcwabevu.” I saw a white unknown woman who was afraid of me. I told her it is going to be okay, and that I would not harm her. But the colour of my skin frightened her. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
- Full Text:
- Date Issued: 2022-04-07
Bond market integration in the Common Monetary Area (CMA)
- Ramoriting, Retšelisitsoe Silvia
- Authors: Ramoriting, Retšelisitsoe Silvia
- Date: 2022-04-06
- Subjects: Globalization , Globalization Economic aspects , Bond market , Rand area , Africa, Southern Economic integration , Autoregressive distributed lag (ARDL) model
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/284592 , vital:56077
- Description: The study reviews the phenomenon of financial integration. During the late 1980s and 1990s, financial market integration around the world increased due to globalisation of investments and the need for higher returns and international risk diversification. The increase was accompanied by a significant increase in private capital flows into developing countries from developed countries. The main goal of the study is to examine bond market integration in the common monetary area The study therefore investigates the co-movement of government bond returns within the CMA using data from Eswatini, Namibia, and South Africa. The study attempts to find the short-run and long-run relationship of these government bond returns using the ARDL cointegration technique. The study uses daily data of 10-year government bond yields spanning from August 2014 to September 2019. The empirical results reveal that there exists a short-run and long-run relationship between South Africa and Eswatini. Between South Africa and Namibia, there only exist a short-run relationship. Just like the previously mentioned studies, the short-run relationship is a result of policy convergence. The lack of long-run relationship between South and Namibia was due to poor institutional developments and limited investment opportunities. In this case, policy measures (or reforms) and a review of the union are necessary to increase integration of these bond markets. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2022
- Full Text:
- Date Issued: 2022-04-06
- Authors: Ramoriting, Retšelisitsoe Silvia
- Date: 2022-04-06
- Subjects: Globalization , Globalization Economic aspects , Bond market , Rand area , Africa, Southern Economic integration , Autoregressive distributed lag (ARDL) model
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/284592 , vital:56077
- Description: The study reviews the phenomenon of financial integration. During the late 1980s and 1990s, financial market integration around the world increased due to globalisation of investments and the need for higher returns and international risk diversification. The increase was accompanied by a significant increase in private capital flows into developing countries from developed countries. The main goal of the study is to examine bond market integration in the common monetary area The study therefore investigates the co-movement of government bond returns within the CMA using data from Eswatini, Namibia, and South Africa. The study attempts to find the short-run and long-run relationship of these government bond returns using the ARDL cointegration technique. The study uses daily data of 10-year government bond yields spanning from August 2014 to September 2019. The empirical results reveal that there exists a short-run and long-run relationship between South Africa and Eswatini. Between South Africa and Namibia, there only exist a short-run relationship. Just like the previously mentioned studies, the short-run relationship is a result of policy convergence. The lack of long-run relationship between South and Namibia was due to poor institutional developments and limited investment opportunities. In this case, policy measures (or reforms) and a review of the union are necessary to increase integration of these bond markets. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2022
- Full Text:
- Date Issued: 2022-04-06
Igalelo lokutshintsha-tshintsha ulwimi xa kufundiswa isiXhosa kwigumbi lokufundela kwibanga le-12
- Authors: Mini, Nolwandle
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54506 , vital:46619
- Description: Olu phando luza kugxila kwigalelo lokutshintsha kolwimi xa kufundiswa isiXhosa kwizikolo ezifundisa isiXhosa kulwimi olongezelweyo. Lo msebenzi wolu phando usekeleze kwigalelo lokutshintshwa tshintshwa kolwimi xa kufundiswa isiXhosa kwigumbi lokufundela. Olu phando luza Kubeka iliso elibanzi kwindlela ekuhlolwa ngalo ulwimi olongezelweleyo kunye nengxelo yeziphumo zokuphela konyaka wama – 2016 nowama- 2017. Abavavanyi kwingxelo zovavanya zovavanyo bayibeke elubala into yokungaphumeleli kwabafundi ngenxa yefuthe lokungawuvi umbuzo. , Thesis (MA) -- Faculty of Humanities, School of Language, Media and Communication, 2021
- Full Text: false
- Date Issued: 2021-12
- Authors: Mini, Nolwandle
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54506 , vital:46619
- Description: Olu phando luza kugxila kwigalelo lokutshintsha kolwimi xa kufundiswa isiXhosa kwizikolo ezifundisa isiXhosa kulwimi olongezelweyo. Lo msebenzi wolu phando usekeleze kwigalelo lokutshintshwa tshintshwa kolwimi xa kufundiswa isiXhosa kwigumbi lokufundela. Olu phando luza Kubeka iliso elibanzi kwindlela ekuhlolwa ngalo ulwimi olongezelweleyo kunye nengxelo yeziphumo zokuphela konyaka wama – 2016 nowama- 2017. Abavavanyi kwingxelo zovavanya zovavanyo bayibeke elubala into yokungaphumeleli kwabafundi ngenxa yefuthe lokungawuvi umbuzo. , Thesis (MA) -- Faculty of Humanities, School of Language, Media and Communication, 2021
- Full Text: false
- Date Issued: 2021-12
“It’s just like a waiting room”: The experiences of psychology Honours students who are not accepted into any professional training programme for psychology in South Africa
- Authors: Duiker, Adeline
- Date: 2021-10-29
- Subjects: Psychology Study and teaching (Higher) South Africa , Psychology students Employment South Africa , Psychology students Attitudes , Psychology Practice South Africa , Professional associations South Africa , Professional education South Africa , Career development South Africa , Universities and colleges Honors courses South Africa , Interpretative Phenomenological Analysis
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/191170 , vital:45067
- Description: Objective: This study explored the lived experiences of currently enrolled psychology Honours students, who are not in a professional training programme for psychology in South Africa. Method: Semi-structured interviews were conducted with eight psychology Honours students at a South African university and analysed using Interpretative Phenomenological Analysis. Findings: Findings revealed that participants perceived an Honours in psychology qualification as significant in personal capacity and insignificant in professional capacity. Additionally, findings showed that participants perceive the difficulty gaining entrance into a professional training programme and lack of employment in the field for Honours psychology graduates, as a contributing factor to several graduates being placed in a state of uncertainty, lacking professional progression in the field of psychology. Furthermore, findings revealed that several Honours psychology students battled to find employment in the field. Conclusions: I critically reflect on the implications of the findings in relation to psychology as a profession in South Africa. , Thesis (MA) -- Faculty of Humanities, Psychology, 2021
- Full Text:
- Date Issued: 2021-10-29
- Authors: Duiker, Adeline
- Date: 2021-10-29
- Subjects: Psychology Study and teaching (Higher) South Africa , Psychology students Employment South Africa , Psychology students Attitudes , Psychology Practice South Africa , Professional associations South Africa , Professional education South Africa , Career development South Africa , Universities and colleges Honors courses South Africa , Interpretative Phenomenological Analysis
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/191170 , vital:45067
- Description: Objective: This study explored the lived experiences of currently enrolled psychology Honours students, who are not in a professional training programme for psychology in South Africa. Method: Semi-structured interviews were conducted with eight psychology Honours students at a South African university and analysed using Interpretative Phenomenological Analysis. Findings: Findings revealed that participants perceived an Honours in psychology qualification as significant in personal capacity and insignificant in professional capacity. Additionally, findings showed that participants perceive the difficulty gaining entrance into a professional training programme and lack of employment in the field for Honours psychology graduates, as a contributing factor to several graduates being placed in a state of uncertainty, lacking professional progression in the field of psychology. Furthermore, findings revealed that several Honours psychology students battled to find employment in the field. Conclusions: I critically reflect on the implications of the findings in relation to psychology as a profession in South Africa. , Thesis (MA) -- Faculty of Humanities, Psychology, 2021
- Full Text:
- Date Issued: 2021-10-29
The relationship between green behaviours and their effect on the performance of small businesses in South Africa
- Authors: Banana, Zingisa
- Date: 2021-01
- Subjects: Small business--Management , Environmental economics
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21377 , vital:48514
- Description: Purpose: Academics and the government are placing more emphasis and importance on the role that enterprises can play in response to challenges of the environment. This study aimed to establish the relationship between green behaviours and the performance of small businesses in South Africa. Green behaviours are measured as consisting of green entrepreneurial orientation, green technology dynamism and green innovation behaviour. Conversely, performance is defined as consisting of environmental performance, objective performance and subjective performance. Design/methodology/approach: To achieve the purpose of this study, the study adopted a positivist paradigm which is motivated by the quantitative approach using a descriptive research design. Self-administered questionnaires were employed with a sample of 180 participants that were randomly selected across small businesses in the Buffalo City Metropolitan Municipality in the Eastern Cape province of South Africa. Findings/results: The major findings of the study, using simple linear regression analysis, revealed that a significant positive relationship between green entrepreneurial orientation and environmental, objective and subjective performance does exist. However, the hierarchical regression analysis results revealed that green technology dynamism and green innovation behaviour do not moderate the relationship between green entrepreneurial orientation and performance as measured by environmental, objective and subjective performance dimensions. Practical implications: Based on the findings of the study, small businesses need to develop policy related to promoting green behaviours, given that green entrepreneurial orientation has been found to be related to performance. Originality/value: The results of this study could guide small business owners and managers in the implementation of environmentally-friendly practices in an effort to reduce green economy issues and environmental problems facing the present generation. , Thesis (MCom) (Business Management) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-01
- Authors: Banana, Zingisa
- Date: 2021-01
- Subjects: Small business--Management , Environmental economics
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21377 , vital:48514
- Description: Purpose: Academics and the government are placing more emphasis and importance on the role that enterprises can play in response to challenges of the environment. This study aimed to establish the relationship between green behaviours and the performance of small businesses in South Africa. Green behaviours are measured as consisting of green entrepreneurial orientation, green technology dynamism and green innovation behaviour. Conversely, performance is defined as consisting of environmental performance, objective performance and subjective performance. Design/methodology/approach: To achieve the purpose of this study, the study adopted a positivist paradigm which is motivated by the quantitative approach using a descriptive research design. Self-administered questionnaires were employed with a sample of 180 participants that were randomly selected across small businesses in the Buffalo City Metropolitan Municipality in the Eastern Cape province of South Africa. Findings/results: The major findings of the study, using simple linear regression analysis, revealed that a significant positive relationship between green entrepreneurial orientation and environmental, objective and subjective performance does exist. However, the hierarchical regression analysis results revealed that green technology dynamism and green innovation behaviour do not moderate the relationship between green entrepreneurial orientation and performance as measured by environmental, objective and subjective performance dimensions. Practical implications: Based on the findings of the study, small businesses need to develop policy related to promoting green behaviours, given that green entrepreneurial orientation has been found to be related to performance. Originality/value: The results of this study could guide small business owners and managers in the implementation of environmentally-friendly practices in an effort to reduce green economy issues and environmental problems facing the present generation. , Thesis (MCom) (Business Management) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-01
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