The isolation, genetic characterisation and biological activity of a South African Phthorimaea operculella granulovirus (PhopGV-SA) for the control of the Potato Tuber Moth, Phthorimaea operculella (Zeller)
- Authors: Jukes, Michael David
- Date: 2015
- Subjects: Potato tuberworm , Potatoes -- Diseases and pests -- South Africa , Baculoviruses , Natural pesticides , Biological pest control agents , Potato tuberworm -- Biological control , Restriction enzymes, DNA
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4147 , http://hdl.handle.net/10962/d1017908
- Description: The potato tuber moth, Phthorimaea operculella (Zeller), is a major pest of potato crops worldwide causing significant damage to both field and stored tubers. The current control method in South Africa involves chemical insecticides, however, there is growing concern on the health and environmental risks of their use. The development of novel biopesticide based control methods may offer a potential solution for the future of insecticides. In this study a baculovirus was successfully isolated from a laboratory population of P. operculella. Transmission electron micrographs revealed granulovirus-like particles. DNA was extracted from recovered occlusion bodies and used for the PCR amplification of the lef-8, lef-9, granulin and egt genes. Sequence data was obtained and submitted to BLAST identifying the virus as a South African isolate of Phthorimaea operculella granulovirus (PhopGV-SA). Phylogenetic analysis of the lef-8, lef-9 and granulin amino acid sequences grouped the South African isolate with PhopGV-1346. Comparison of egt sequence data identified PhopGV-SA as a type II egt gene. A phylogenetic analysis of egt amino acid sequences grouped all type II genes, including PhopGV-SA, into a separate clade from types I, III, IV and V. These findings suggest that type II may represent the prototype structure for this gene with the evolution of types I, III and IV a result of large internal deletion events and subsequent divergence. PhopGV-SA was also shown to be genetically more similar to South American isolates (i.e. PhopGV-CHI or PhopGV-INDO) than it is to other African isolates, suggesting that the South African isolate originated from South America. Restriction endonuclease profiles of PhopGV-SA were similar to those of PhopGV-1346 and PhopGV-JLZ9f for the enzymes BamHI, HindIII, NruI and NdeI. A preliminary full genome sequence for PhopGV-SA was determined and compared to PhopGV-136 with some gene variation observed (i.e. odv-e66 and vp91/p95). The biological activity of PhopGV-SA against P. operculella neonate larvae was evaluated with an estimated LC₅₀ of 1.87×10⁸ OBs.ml⁻¹ being determined. This study therefore reports the characterisation of a novel South African PhopGV isolate which could potentially be developed into a biopesticide for the control of P. operculella.
- Full Text:
- Date Issued: 2015
- Authors: Jukes, Michael David
- Date: 2015
- Subjects: Potato tuberworm , Potatoes -- Diseases and pests -- South Africa , Baculoviruses , Natural pesticides , Biological pest control agents , Potato tuberworm -- Biological control , Restriction enzymes, DNA
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4147 , http://hdl.handle.net/10962/d1017908
- Description: The potato tuber moth, Phthorimaea operculella (Zeller), is a major pest of potato crops worldwide causing significant damage to both field and stored tubers. The current control method in South Africa involves chemical insecticides, however, there is growing concern on the health and environmental risks of their use. The development of novel biopesticide based control methods may offer a potential solution for the future of insecticides. In this study a baculovirus was successfully isolated from a laboratory population of P. operculella. Transmission electron micrographs revealed granulovirus-like particles. DNA was extracted from recovered occlusion bodies and used for the PCR amplification of the lef-8, lef-9, granulin and egt genes. Sequence data was obtained and submitted to BLAST identifying the virus as a South African isolate of Phthorimaea operculella granulovirus (PhopGV-SA). Phylogenetic analysis of the lef-8, lef-9 and granulin amino acid sequences grouped the South African isolate with PhopGV-1346. Comparison of egt sequence data identified PhopGV-SA as a type II egt gene. A phylogenetic analysis of egt amino acid sequences grouped all type II genes, including PhopGV-SA, into a separate clade from types I, III, IV and V. These findings suggest that type II may represent the prototype structure for this gene with the evolution of types I, III and IV a result of large internal deletion events and subsequent divergence. PhopGV-SA was also shown to be genetically more similar to South American isolates (i.e. PhopGV-CHI or PhopGV-INDO) than it is to other African isolates, suggesting that the South African isolate originated from South America. Restriction endonuclease profiles of PhopGV-SA were similar to those of PhopGV-1346 and PhopGV-JLZ9f for the enzymes BamHI, HindIII, NruI and NdeI. A preliminary full genome sequence for PhopGV-SA was determined and compared to PhopGV-136 with some gene variation observed (i.e. odv-e66 and vp91/p95). The biological activity of PhopGV-SA against P. operculella neonate larvae was evaluated with an estimated LC₅₀ of 1.87×10⁸ OBs.ml⁻¹ being determined. This study therefore reports the characterisation of a novel South African PhopGV isolate which could potentially be developed into a biopesticide for the control of P. operculella.
- Full Text:
- Date Issued: 2015
Strategic thinking during a period of turbulence : a case study of the BancABC Zimbabwe
- Authors: Mberi, Mary-Jane
- Date: 2015
- Subjects: BancABC (Zimbabwe) , Strategic planning -- Case studies , Strategic planning -- Zimbabwe , Inflation (Finance) -- Zimbabwe , Problem solving -- Zimbabwe , Crisis management -- Zimbabwe , Decision making -- Zimbabwe , Critical incident technique
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:861 , http://hdl.handle.net/10962/d1020603
- Description: A review of strategic thinking literature indicates that research has tended to focus on experiences contributing to strategic thinking, the strategic thinking perspectives that executives are likely to follow based on the environments in which they have developed their strategic competencies, and examining executives’ cognitive maps within the context of strategic management (O’ Shannassy 2003; Kutschera, and Ryan, 2009; Meyer, 2007). As an expansion of these principles and foundations of strategic thinking, this research was a study of the extent to which strategic thinking perspectives are utilised during macro environmental turbulence. According to Cravens et al. (2009: 31) volatility, reinvention, and fundamental changes in markets present unprecedented challenges to researchers and executives. “Unfortunately, too often traditional conceptual models and theories fail to provide adequate insight for coping with this new and rapidly changing business environment. Traditional market perspectives and conceptual logic may even blind researchers and strategic decision makers to the real threats present in the changing competitive landscape and new market space, and to opportunities for added value which can be uncovered and exploited” Cravens et al. (2009: 31). Hyperinflation in Zimbabwe was a major problem from 2003 to April 2009, when the country suspended its own currency and for the next five years the country continued to struggle with various macro environmental challenges. It is this backdrop that makes this research intriguing, where the soundness of any organisation is said to be crucially linked to the soundness of the macro environment, including macroeconomic policies as well as internal governance, market discipline; regulation and supervision (Louw and Venter, 2010). The research was a case study of BancABC Zimbabwe and focused on the period 2009 to 2013. BancABC Zimbabwe is a subsidiary of ABC Holdings Limited which is listed on the Botswana and Zimbabwe stock exchanges (BancABC, 2012). The aim of the study as the first key activity was to explore and describe how the BancABC executives responded to the critical macro environmental incidents identified, at a management or executive team perspective, and secondly, whether the rational reasoning or generative reasoning perspective was dominant during the period of turbulence. The goal is to gain insights of the strategic thinking process followed by executives during a period of macro-environmental turbulence. Literature defines strategic thinking concept as the cognitive process undertaken by executives in relation to problem solving in the business context. Two main perspectives are discussed: Strategic thinking as a science (rational thinking) is the prescriptive, structured nature of strategic thinking; arguments are that it is a less complex perspective for executives to adopt. Strategic thinking as an art (generative thinking) is the perspective that allows the strategist to think outside the box and be more creative about solving strategic problems. The discussion presents how the two perspectives can be used to complement each other and provide a more robust strategic thinking framework. The multi-perspective approach to strategic thinking recommends the right balance between analysis, intuition and creativity can be used to create new frameworks and innovative solutions. The ability to balance these strategic thinking perspectives enables executives to solve strategic problems (Linkov, 1999). The research findings highlighted the effect of time and availability of information on the strategic thinking perspective adopted by executives during times of uncertainty. It was noted that when time and information were available, executives appeared to use the rational strategic thinking perspective, while if there was limited time and information to solve problems the generative thinking perspective was dominantly used. Further the importance of integrative strategic thinking which facilitates the use of both intuition and analysis when solving strategic problems in a turbulent macro environment was also highlighted. The research thesis adopted the structure of a case study, relying on the critical incident technique to create the context of the study; and can be used to explore and discuss strategic thinking for teaching purposes. The results of the study can be recognised as a contribution towards the development of strategic thinking particularly in times of turbulence. It can also form the basis for future studies in the context of strategic thinking.
- Full Text:
- Date Issued: 2015
- Authors: Mberi, Mary-Jane
- Date: 2015
- Subjects: BancABC (Zimbabwe) , Strategic planning -- Case studies , Strategic planning -- Zimbabwe , Inflation (Finance) -- Zimbabwe , Problem solving -- Zimbabwe , Crisis management -- Zimbabwe , Decision making -- Zimbabwe , Critical incident technique
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:861 , http://hdl.handle.net/10962/d1020603
- Description: A review of strategic thinking literature indicates that research has tended to focus on experiences contributing to strategic thinking, the strategic thinking perspectives that executives are likely to follow based on the environments in which they have developed their strategic competencies, and examining executives’ cognitive maps within the context of strategic management (O’ Shannassy 2003; Kutschera, and Ryan, 2009; Meyer, 2007). As an expansion of these principles and foundations of strategic thinking, this research was a study of the extent to which strategic thinking perspectives are utilised during macro environmental turbulence. According to Cravens et al. (2009: 31) volatility, reinvention, and fundamental changes in markets present unprecedented challenges to researchers and executives. “Unfortunately, too often traditional conceptual models and theories fail to provide adequate insight for coping with this new and rapidly changing business environment. Traditional market perspectives and conceptual logic may even blind researchers and strategic decision makers to the real threats present in the changing competitive landscape and new market space, and to opportunities for added value which can be uncovered and exploited” Cravens et al. (2009: 31). Hyperinflation in Zimbabwe was a major problem from 2003 to April 2009, when the country suspended its own currency and for the next five years the country continued to struggle with various macro environmental challenges. It is this backdrop that makes this research intriguing, where the soundness of any organisation is said to be crucially linked to the soundness of the macro environment, including macroeconomic policies as well as internal governance, market discipline; regulation and supervision (Louw and Venter, 2010). The research was a case study of BancABC Zimbabwe and focused on the period 2009 to 2013. BancABC Zimbabwe is a subsidiary of ABC Holdings Limited which is listed on the Botswana and Zimbabwe stock exchanges (BancABC, 2012). The aim of the study as the first key activity was to explore and describe how the BancABC executives responded to the critical macro environmental incidents identified, at a management or executive team perspective, and secondly, whether the rational reasoning or generative reasoning perspective was dominant during the period of turbulence. The goal is to gain insights of the strategic thinking process followed by executives during a period of macro-environmental turbulence. Literature defines strategic thinking concept as the cognitive process undertaken by executives in relation to problem solving in the business context. Two main perspectives are discussed: Strategic thinking as a science (rational thinking) is the prescriptive, structured nature of strategic thinking; arguments are that it is a less complex perspective for executives to adopt. Strategic thinking as an art (generative thinking) is the perspective that allows the strategist to think outside the box and be more creative about solving strategic problems. The discussion presents how the two perspectives can be used to complement each other and provide a more robust strategic thinking framework. The multi-perspective approach to strategic thinking recommends the right balance between analysis, intuition and creativity can be used to create new frameworks and innovative solutions. The ability to balance these strategic thinking perspectives enables executives to solve strategic problems (Linkov, 1999). The research findings highlighted the effect of time and availability of information on the strategic thinking perspective adopted by executives during times of uncertainty. It was noted that when time and information were available, executives appeared to use the rational strategic thinking perspective, while if there was limited time and information to solve problems the generative thinking perspective was dominantly used. Further the importance of integrative strategic thinking which facilitates the use of both intuition and analysis when solving strategic problems in a turbulent macro environment was also highlighted. The research thesis adopted the structure of a case study, relying on the critical incident technique to create the context of the study; and can be used to explore and discuss strategic thinking for teaching purposes. The results of the study can be recognised as a contribution towards the development of strategic thinking particularly in times of turbulence. It can also form the basis for future studies in the context of strategic thinking.
- Full Text:
- Date Issued: 2015
Using experience from previous failed implementations to improve future lean implementation strategy
- Authors: Hiles, Charmelle Amanda
- Date: 2015
- Subjects: Lean manufacturing -- Management Production planning
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/11047 , vital:26880
- Description: The main objective of the study was to ascertain the presence of the identified critical success factors for lean sustainability in a chemical manufacturing company in Port Elizabeth. The critical success factors that formed part of the research included leadership involvement and commitment, management involvement and commitment, employee engagement and organisational culture. The methodology used was one of a positivistic approach. A questionnaire was utilized and the responses were analyzed using various statistical methods. Based on the results from the analysis, recommendations and conclusions could be drawn. The inferential results of the study indicated that all the critical success factors identified for this study were present within the organisation. However, there were still a large percentage of respondents that remained neutral across all the questions which could indicate reasons why previous attempts in lean implementation failed. The recommendations provided were based on the findings of the study. An implementation strategy was identified and outlined. This strategy and recommendations will assist in providing a sound platform for a sustainable lean initiative within the organisation.
- Full Text:
- Date Issued: 2015
Using experience from previous failed implementations to improve future lean implementation strategy
- Authors: Hiles, Charmelle Amanda
- Date: 2015
- Subjects: Lean manufacturing -- Management Production planning
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/11047 , vital:26880
- Description: The main objective of the study was to ascertain the presence of the identified critical success factors for lean sustainability in a chemical manufacturing company in Port Elizabeth. The critical success factors that formed part of the research included leadership involvement and commitment, management involvement and commitment, employee engagement and organisational culture. The methodology used was one of a positivistic approach. A questionnaire was utilized and the responses were analyzed using various statistical methods. Based on the results from the analysis, recommendations and conclusions could be drawn. The inferential results of the study indicated that all the critical success factors identified for this study were present within the organisation. However, there were still a large percentage of respondents that remained neutral across all the questions which could indicate reasons why previous attempts in lean implementation failed. The recommendations provided were based on the findings of the study. An implementation strategy was identified and outlined. This strategy and recommendations will assist in providing a sound platform for a sustainable lean initiative within the organisation.
- Full Text:
- Date Issued: 2015
Investigation into the characteristics and possible applications of biomass gasification by-products from a downdraft gasifier system
- Authors: Melapi, Aviwe
- Date: 2015
- Subjects: Biomass gasification -- South Africa -- Eastern Cape , Renewable energy sources -- South Africa -- Eastern Cape , Biomass energy -- South Africa -- Eastern Cape , Crop residue management -- South Africa -- Eastern Cape , Coal gasification -- South Africa -- Eastern Cape , Lignocellulose -- Biodegradation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11348 , http://hdl.handle.net/10353/d1020174 , Biomass gasification -- South Africa -- Eastern Cape , Renewable energy sources -- South Africa -- Eastern Cape , Biomass energy -- South Africa -- Eastern Cape , Crop residue management -- South Africa -- Eastern Cape , Coal gasification -- South Africa -- Eastern Cape , Lignocellulose -- Biodegradation -- South Africa -- Eastern Cape
- Description: Biomass gasification has attracted the interest of researchers because it produces zero carbon to the atmosphere. This technology does not only produce syngas but also the byproducts which can be used for various application depending on quality.The study conducted at Melani village in Alice in the Eastern Cape of South Africa was aimed at investigating the possible applications of the gasification byproducts instead of being thrown away. Pine wood was employed as the parent feedstock material for the gasifier. Biomass gasification by-products were then collected for further analysis. The studied by-products included tar(condensate), char, soot and resin. These materials were also blended to produce strong materials.The essence of the blending was to generate ideal material that is strong but light at the same time.The elemental analysis of the samples performed by CHNS analyser revealed that carbon element is in large quantities in all samples. The FTIR spectra showed almost similar results for all the studied samples, since the samples are end products of lignocellulosegasification. SEM gave the sticky images of resin as well as porous char structures. Char showed a higher heating value of 35.37MJ/Kg when compared to other by-products samples.
- Full Text:
- Date Issued: 2015
- Authors: Melapi, Aviwe
- Date: 2015
- Subjects: Biomass gasification -- South Africa -- Eastern Cape , Renewable energy sources -- South Africa -- Eastern Cape , Biomass energy -- South Africa -- Eastern Cape , Crop residue management -- South Africa -- Eastern Cape , Coal gasification -- South Africa -- Eastern Cape , Lignocellulose -- Biodegradation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11348 , http://hdl.handle.net/10353/d1020174 , Biomass gasification -- South Africa -- Eastern Cape , Renewable energy sources -- South Africa -- Eastern Cape , Biomass energy -- South Africa -- Eastern Cape , Crop residue management -- South Africa -- Eastern Cape , Coal gasification -- South Africa -- Eastern Cape , Lignocellulose -- Biodegradation -- South Africa -- Eastern Cape
- Description: Biomass gasification has attracted the interest of researchers because it produces zero carbon to the atmosphere. This technology does not only produce syngas but also the byproducts which can be used for various application depending on quality.The study conducted at Melani village in Alice in the Eastern Cape of South Africa was aimed at investigating the possible applications of the gasification byproducts instead of being thrown away. Pine wood was employed as the parent feedstock material for the gasifier. Biomass gasification by-products were then collected for further analysis. The studied by-products included tar(condensate), char, soot and resin. These materials were also blended to produce strong materials.The essence of the blending was to generate ideal material that is strong but light at the same time.The elemental analysis of the samples performed by CHNS analyser revealed that carbon element is in large quantities in all samples. The FTIR spectra showed almost similar results for all the studied samples, since the samples are end products of lignocellulosegasification. SEM gave the sticky images of resin as well as porous char structures. Char showed a higher heating value of 35.37MJ/Kg when compared to other by-products samples.
- Full Text:
- Date Issued: 2015
A re-examination of the type material of Entomoneis paludosa (W Smith) Reimer and its morphology and distribution in African waters
- Richoux, Nicole B, Taylor, J C, Dalu, Tatenda, Froneman, P William
- Authors: Richoux, Nicole B , Taylor, J C , Dalu, Tatenda , Froneman, P William
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69179 , vital:29440 , https://doi.org/10.5507/fot.2015.002
- Description: The current study aims to enhance the understanding of the distribution and morphology of the diatom Entomoneis paludosa W Smith 1853 in African waters. The type material of Entomoneis paludosa (W Smith) Reimer was examined using light and scanning electron microscopy and the morphological characters were compared with new specimens sampled from a temperate river in South Africa. The wider distribution of this taxon on the African continent is discussed, and its relationship to water quality variables.
- Full Text:
- Date Issued: 2015
- Authors: Richoux, Nicole B , Taylor, J C , Dalu, Tatenda , Froneman, P William
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69179 , vital:29440 , https://doi.org/10.5507/fot.2015.002
- Description: The current study aims to enhance the understanding of the distribution and morphology of the diatom Entomoneis paludosa W Smith 1853 in African waters. The type material of Entomoneis paludosa (W Smith) Reimer was examined using light and scanning electron microscopy and the morphological characters were compared with new specimens sampled from a temperate river in South Africa. The wider distribution of this taxon on the African continent is discussed, and its relationship to water quality variables.
- Full Text:
- Date Issued: 2015
Reconceptualising notions of South African Indianess : a personal narrative
- Authors: Kunvar, Yogita
- Date: 2015
- Subjects: East Indians -- South Africa , East Indians -- South Africa -- Ethnic identity , East Indians -- Cultural assimilation -- South Africa , National characteristics, East Indian , East Indian diaspora , Identity (Psychology) , South Africa -- Social conditions -- 1961-1994 , South Africa -- Politics and government -- 1948-1994 , South Africa -- Race relations
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:2123 , http://hdl.handle.net/10962/d1017767
- Description: The theoretical challenge of conceptualising South African Indianess is suffused with a plethora of variables that suggest complexity. While being misleadingly homogenous, Indian identity encompasses a multitude of expressions. This thesis seeks to reconceptualise notions of South African Indianess through personal narrative. The research context is contemporary South Africa with a specific focus on Johannesburg’s East Rand Reef. Inspired by the dearth of literature on contemporary Indianess this study addresses the gap in the present discourse. Following the autoethnographic work of Motzafi-Haller (1997) and Narayan (1993) the thesis presents a layered narrative by juxtaposing the experiences of research participants with my own. Using multi-sited autoethnographic data the thesis explores the question of what it means to be Indian in relation to South Africa’s Apartheid past. By drawing on concepts in popular diaspora theory and critiquing their application, the thesis illustrates the inadequacies inherent in the definitions of diaspora and suggests a broader understanding of its application. Through exploring layers of Indianess the thesis illustrates the inherent complexity in reconceptualising South African Indianess. The study suggests that as a result of changing global and local flows, South African Indians are reconceptualising what it means to be South African Indian.
- Full Text:
- Date Issued: 2015
- Authors: Kunvar, Yogita
- Date: 2015
- Subjects: East Indians -- South Africa , East Indians -- South Africa -- Ethnic identity , East Indians -- Cultural assimilation -- South Africa , National characteristics, East Indian , East Indian diaspora , Identity (Psychology) , South Africa -- Social conditions -- 1961-1994 , South Africa -- Politics and government -- 1948-1994 , South Africa -- Race relations
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:2123 , http://hdl.handle.net/10962/d1017767
- Description: The theoretical challenge of conceptualising South African Indianess is suffused with a plethora of variables that suggest complexity. While being misleadingly homogenous, Indian identity encompasses a multitude of expressions. This thesis seeks to reconceptualise notions of South African Indianess through personal narrative. The research context is contemporary South Africa with a specific focus on Johannesburg’s East Rand Reef. Inspired by the dearth of literature on contemporary Indianess this study addresses the gap in the present discourse. Following the autoethnographic work of Motzafi-Haller (1997) and Narayan (1993) the thesis presents a layered narrative by juxtaposing the experiences of research participants with my own. Using multi-sited autoethnographic data the thesis explores the question of what it means to be Indian in relation to South Africa’s Apartheid past. By drawing on concepts in popular diaspora theory and critiquing their application, the thesis illustrates the inadequacies inherent in the definitions of diaspora and suggests a broader understanding of its application. Through exploring layers of Indianess the thesis illustrates the inherent complexity in reconceptualising South African Indianess. The study suggests that as a result of changing global and local flows, South African Indians are reconceptualising what it means to be South African Indian.
- Full Text:
- Date Issued: 2015
Ni(II) and Pb(II) dithiocarbamate complexes as precursors for the synthesis of HDA-capped NiS and PbS nanoparticles
- Authors: Chintso, Thobani
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11349 , http://hdl.handle.net/10353/d1020201
- Description: Ni(II) and Pb(II) dithiocarbamate complexes were synthesized and characterized by elemental analysis, UV-Vis, FTIR and TGA and some of the Ni(II) complexes and one Pb(II) were further analyzed by 1H-NMR and 13C-NMR spectroscopy. Generally all the dithiocarbamate ligands are soluble in water while the complexes were soluble mostly in solvents such as chloroform, toluene, DMSO and DCM. Based on the elemental analysis, the dithiocarbamate complexes are formulated as four coordinate (tetrahedral or square planar) compounds. However, the FTIR showed that each of the dithiocarbamate ligands acted as bidentate ligand through two sulfur atoms. The TGA of the most complexes showed one major decomposition step to give respective metal sulfide above 200 oC. In this research project, dithiocarbamate complexes were used as single source precursor for the synthesis of metal sulfide nanoparticles. We studied the optical and structural properties of metal sulfide nanoparticles using UV-Vis, photoluminescence (PL), powder X-ray diffraction (XRD), energy dispersive X-ray (EDX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The absorption spectra of the metal sulfide nanoparticles are blue shifted in respect to bulk material and they also showed broad emission. The XRD of the NiS nanoparticles were indexed to the cubic and rhombohedral phase, with crystallite sizes of 15 - 18 nm. The XRD of PbS nanoparticles were indexed to the face centered cubic and cubic rock salts, with the crystallite sizes 12 - 18 nm. The TEM images of the metal sulfide nanoparticles showed particles with spherical and rectangular shapes with crystallite sizes 4 - 35 nm.
- Full Text:
- Date Issued: 2015
- Authors: Chintso, Thobani
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11349 , http://hdl.handle.net/10353/d1020201
- Description: Ni(II) and Pb(II) dithiocarbamate complexes were synthesized and characterized by elemental analysis, UV-Vis, FTIR and TGA and some of the Ni(II) complexes and one Pb(II) were further analyzed by 1H-NMR and 13C-NMR spectroscopy. Generally all the dithiocarbamate ligands are soluble in water while the complexes were soluble mostly in solvents such as chloroform, toluene, DMSO and DCM. Based on the elemental analysis, the dithiocarbamate complexes are formulated as four coordinate (tetrahedral or square planar) compounds. However, the FTIR showed that each of the dithiocarbamate ligands acted as bidentate ligand through two sulfur atoms. The TGA of the most complexes showed one major decomposition step to give respective metal sulfide above 200 oC. In this research project, dithiocarbamate complexes were used as single source precursor for the synthesis of metal sulfide nanoparticles. We studied the optical and structural properties of metal sulfide nanoparticles using UV-Vis, photoluminescence (PL), powder X-ray diffraction (XRD), energy dispersive X-ray (EDX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The absorption spectra of the metal sulfide nanoparticles are blue shifted in respect to bulk material and they also showed broad emission. The XRD of the NiS nanoparticles were indexed to the cubic and rhombohedral phase, with crystallite sizes of 15 - 18 nm. The XRD of PbS nanoparticles were indexed to the face centered cubic and cubic rock salts, with the crystallite sizes 12 - 18 nm. The TEM images of the metal sulfide nanoparticles showed particles with spherical and rectangular shapes with crystallite sizes 4 - 35 nm.
- Full Text:
- Date Issued: 2015
Caring for a child with disabilities: a psychosocial case study
- Saville Young, Lisa, Berry, Jessie
- Authors: Saville Young, Lisa , Berry, Jessie
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143860 , vital:38289 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: This paper presents a psychosocial analysis of an interview with a mother of a child with disabilities. A psychosocial perspective (conceptualizing the subject as both discursively and psychically constituted) has been argued for recently in critical disability studies by Goodley (2011) who advocates for psychoanalysis’ rich vocabulary for affective processes to explore the emotional elements of disablism, where disablism refers to ways in which society discriminates against people with disabilities (‘barriers out there’). While rejecting the use of psychoanalytic theory to pathologise and individualise people with disabilities, Goodley argues that how “oppression is felt psychically, subjectively and emotionally” (p.716) (‘barriers in here’) should not be overlooked, alongside subjectivity as always socially, politically, culturally and economically produced. This psychosocial analysis of a carer’s perspective thickens our understanding of how the caregiver is a social being, both not disabled but at the receiving end of disablism, and an interpersonal subject who may also be an ‘agent’ or ‘carrier’ of disablism.
- Full Text:
- Date Issued: 2015
- Authors: Saville Young, Lisa , Berry, Jessie
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143860 , vital:38289 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: This paper presents a psychosocial analysis of an interview with a mother of a child with disabilities. A psychosocial perspective (conceptualizing the subject as both discursively and psychically constituted) has been argued for recently in critical disability studies by Goodley (2011) who advocates for psychoanalysis’ rich vocabulary for affective processes to explore the emotional elements of disablism, where disablism refers to ways in which society discriminates against people with disabilities (‘barriers out there’). While rejecting the use of psychoanalytic theory to pathologise and individualise people with disabilities, Goodley argues that how “oppression is felt psychically, subjectively and emotionally” (p.716) (‘barriers in here’) should not be overlooked, alongside subjectivity as always socially, politically, culturally and economically produced. This psychosocial analysis of a carer’s perspective thickens our understanding of how the caregiver is a social being, both not disabled but at the receiving end of disablism, and an interpersonal subject who may also be an ‘agent’ or ‘carrier’ of disablism.
- Full Text:
- Date Issued: 2015
Physicochemical behavior of nanohybrids of mono and tetra substituted carboxyphenoxy phthalocyanine covalently linked to GSH–CdTe/CdS/ZnS quantum dots
- Oluwole, David O, Nyokong, Tebello
- Authors: Oluwole, David O , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189480 , vital:44850 , xlink:href="https://doi.org/10.1016/j.poly.2014.10.024"
- Description: Zinc monocarboxyphenoxy and tetracarboxyphenoxy phthalocyanines were covalently linked with three different sizes of glutathione capped core/shell/shell {CdTe/CdS/ZnS(4.2), CdTe/CdS/ZnS(5.1) and CdTe/CdS/ZnS(6.7)}; a core shell {CdTe/CdS(3.1)} and core {CdTe(2.4)} quantum dots. The physicochemical behavior and Förster resonance energy transfer (FRET) processes of the nanohybrids were investigated. The highest FRET efficiency was observed with CdTe/CdS/ZnS(6.7) nanohybrids with 98% and the least efficiency was observed with CdTe(2.4) nanohybrids with 85%. The CdTe/CdS/ZnS(6.7) also showed the best physicochemical behavior. These good physicochemical properties make the synthesized nanohybrids viable photosensitizers.
- Full Text:
- Date Issued: 2015
- Authors: Oluwole, David O , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189480 , vital:44850 , xlink:href="https://doi.org/10.1016/j.poly.2014.10.024"
- Description: Zinc monocarboxyphenoxy and tetracarboxyphenoxy phthalocyanines were covalently linked with three different sizes of glutathione capped core/shell/shell {CdTe/CdS/ZnS(4.2), CdTe/CdS/ZnS(5.1) and CdTe/CdS/ZnS(6.7)}; a core shell {CdTe/CdS(3.1)} and core {CdTe(2.4)} quantum dots. The physicochemical behavior and Förster resonance energy transfer (FRET) processes of the nanohybrids were investigated. The highest FRET efficiency was observed with CdTe/CdS/ZnS(6.7) nanohybrids with 98% and the least efficiency was observed with CdTe(2.4) nanohybrids with 85%. The CdTe/CdS/ZnS(6.7) also showed the best physicochemical behavior. These good physicochemical properties make the synthesized nanohybrids viable photosensitizers.
- Full Text:
- Date Issued: 2015
A model for mobile, context-aware in-car communication systems to reduce driver distractions
- Authors: Tchankue-Sielinou, Patrick
- Date: 2015
- Subjects: Automobiles -- Safety measures , Context-aware computing , Mobile communication systems
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/4144 , vital:20556
- Description: Driver distraction remains a matter of concern throughout the world as the number of car accidents caused by distracted driving is still unacceptably high. Industry and academia are working intensively to design new techniques that will address all types of driver distraction including visual, manual, auditory and cognitive distraction. This research focuses on an existing technology, namely in-car communication systems (ICCS). ICCS allow drivers to interact with their mobile phones without touching or looking at them. Previous research suggests that ICCS have reduced visual and manual distraction. Two problems were identified in this research: existing ICCS are still expensive and only available in limited models of car. As a result of that, only a small number of drivers can obtain a car equipped with an ICCS, especially in developing countries. The second problem is that existing ICCS are not aware of the driving context, which plays a role in distracting drivers. This research project was based on the following thesis statement: A mobile, context-aware model can be designed to reduce driver distraction caused by the use of ICCS. A mobile ICCS is portable and can be used in any car, addressing the first problem. Context-awareness will be used to detect possible situations that contribute to distracting drivers and the interaction with the mobile ICCS will be adapted so as to avert calls and text messages. This will address the second problem. As the driving context is dynamic, drivers may have to deal with critical safety-related tasks while they are using an existing ICCS. The following steps were taken in order to validate the thesis statement. An investigation was conducted into the causes and consequences of driver distraction. A review of literature was conducted on context-aware techniques that could potentially be used. The design of a model was proposed, called the Multimodal Interface for Mobile Info-communication with Context (MIMIC) and a preliminary usability evaluation was conducted in order to assess the feasibility of a speech-based, mobile ICCS. Despite some problems with the speech recognition, the results were satisfying and showed that the proposed model for mobile ICCS was feasible. Experiments were conducted in order to collect data to perform supervised learning to determine the driving context. The aim was to select the most effective machine learning techniques to determine the driving context. Decision tree and instance-based algorithms were found to be the best performing algorithms. Variables such as speed, acceleration and linear acceleration were found to be the most important variables according to an analysis of the decision tree. The initial MIMIC model was updated to include several adaptation effects and the resulting model was implemented as a prototype mobile application, called MIMIC-Prototype.
- Full Text:
- Date Issued: 2015
- Authors: Tchankue-Sielinou, Patrick
- Date: 2015
- Subjects: Automobiles -- Safety measures , Context-aware computing , Mobile communication systems
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/4144 , vital:20556
- Description: Driver distraction remains a matter of concern throughout the world as the number of car accidents caused by distracted driving is still unacceptably high. Industry and academia are working intensively to design new techniques that will address all types of driver distraction including visual, manual, auditory and cognitive distraction. This research focuses on an existing technology, namely in-car communication systems (ICCS). ICCS allow drivers to interact with their mobile phones without touching or looking at them. Previous research suggests that ICCS have reduced visual and manual distraction. Two problems were identified in this research: existing ICCS are still expensive and only available in limited models of car. As a result of that, only a small number of drivers can obtain a car equipped with an ICCS, especially in developing countries. The second problem is that existing ICCS are not aware of the driving context, which plays a role in distracting drivers. This research project was based on the following thesis statement: A mobile, context-aware model can be designed to reduce driver distraction caused by the use of ICCS. A mobile ICCS is portable and can be used in any car, addressing the first problem. Context-awareness will be used to detect possible situations that contribute to distracting drivers and the interaction with the mobile ICCS will be adapted so as to avert calls and text messages. This will address the second problem. As the driving context is dynamic, drivers may have to deal with critical safety-related tasks while they are using an existing ICCS. The following steps were taken in order to validate the thesis statement. An investigation was conducted into the causes and consequences of driver distraction. A review of literature was conducted on context-aware techniques that could potentially be used. The design of a model was proposed, called the Multimodal Interface for Mobile Info-communication with Context (MIMIC) and a preliminary usability evaluation was conducted in order to assess the feasibility of a speech-based, mobile ICCS. Despite some problems with the speech recognition, the results were satisfying and showed that the proposed model for mobile ICCS was feasible. Experiments were conducted in order to collect data to perform supervised learning to determine the driving context. The aim was to select the most effective machine learning techniques to determine the driving context. Decision tree and instance-based algorithms were found to be the best performing algorithms. Variables such as speed, acceleration and linear acceleration were found to be the most important variables according to an analysis of the decision tree. The initial MIMIC model was updated to include several adaptation effects and the resulting model was implemented as a prototype mobile application, called MIMIC-Prototype.
- Full Text:
- Date Issued: 2015
Evaluation of microinsurance distribution strategy at the bottom of the pyramid by Liberty Life Swaziland
- Authors: Lukhele, Mlungisi Reginald
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/54474 , vital:26568
- Description: This is a qualitative study which focuses on how Liberty Life Swaziland distributes microinsurance to the bottom of the pyramid within Swaziland. Using stratified purposive sampling, this study identified 5 managers within Liberty Life and 4 managers from brokerages and affinity partners who had a minimum of 3 years’ experience in distribution of microinsurance. Semi-structured and in-depth interviews were conducted by the researcher with these managers. Interviews were stopped when there was data saturation. To induce emerging themes from the data, open-coding and constant comparison technique was used. Findings in this study reveal that to distribute microinsurance to low income households, Liberty Life objectives are to; (1) provide relevant solutions in a cost effective manner, thus keeping premiums as affordable as possible, (2) provide simple products which are easy to understand by customers, (3) make services accessible, and (4) make doing business easy. In this regard, Liberty Life distribution strategy is to partner with bulk retailing entities that have a client base they already service and benefit from nationwide presence and infrastructure. Lastly, the perspectives of both internal and external stakeholders in microinsurance are discussed to evaluate the challenges and successes experienced in implementing the distribution strategy. This study is valuable to critically understand the current distribution strategy from the viewpoint of key intermediaries, but also pinpoint how efforts to achieve microinsurance distribution objectives can be enhanced. Lastly, the study recommends that; a selection criteria be set for distribution partners, partnership with mobile network operators, investment in continuous training of distribution partners and knowledge sharing between Liberty and intermediaries to cease the opportunity at the bottom of the pyramid.
- Full Text:
- Date Issued: 2015
- Authors: Lukhele, Mlungisi Reginald
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/54474 , vital:26568
- Description: This is a qualitative study which focuses on how Liberty Life Swaziland distributes microinsurance to the bottom of the pyramid within Swaziland. Using stratified purposive sampling, this study identified 5 managers within Liberty Life and 4 managers from brokerages and affinity partners who had a minimum of 3 years’ experience in distribution of microinsurance. Semi-structured and in-depth interviews were conducted by the researcher with these managers. Interviews were stopped when there was data saturation. To induce emerging themes from the data, open-coding and constant comparison technique was used. Findings in this study reveal that to distribute microinsurance to low income households, Liberty Life objectives are to; (1) provide relevant solutions in a cost effective manner, thus keeping premiums as affordable as possible, (2) provide simple products which are easy to understand by customers, (3) make services accessible, and (4) make doing business easy. In this regard, Liberty Life distribution strategy is to partner with bulk retailing entities that have a client base they already service and benefit from nationwide presence and infrastructure. Lastly, the perspectives of both internal and external stakeholders in microinsurance are discussed to evaluate the challenges and successes experienced in implementing the distribution strategy. This study is valuable to critically understand the current distribution strategy from the viewpoint of key intermediaries, but also pinpoint how efforts to achieve microinsurance distribution objectives can be enhanced. Lastly, the study recommends that; a selection criteria be set for distribution partners, partnership with mobile network operators, investment in continuous training of distribution partners and knowledge sharing between Liberty and intermediaries to cease the opportunity at the bottom of the pyramid.
- Full Text:
- Date Issued: 2015
A positive clinical psychology approach to developing resilience among state employed nurses
- Authors: Plumb, Sarah
- Date: 2015
- Subjects: Nurses -- Job stress , Nursing -- Psychological aspects , Resilience (Personality trait)
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9955 , http://hdl.handle.net/10948/d1018879
- Description: Nurses are confronted with numerous work-related stressors that can result in burnout. This can contribute to absenteeism and high turn-over rates in the nursing profession. A review of the literature indicated that psycho-educational interventions to increase resilience could be an effective way of addressing this problem. The study aimed to develop a positive clinical-psychology approach to increasing resilience in State employed nurses. The study used a mixed-method approach to determine the current psychological functioning of a sample of 87 nurses. Quantitative data on personality traits, character strengths and levels of resilience were obtained, using the NEO PI-R, VIA – IS, and Resilience Scale. Qualitative data on the coping responses of nurses were obtained through the thematic analysis of focus groups. These data were integrated to create a positive clinical psychology conceptualisation of resilience and to develop therapeutic guidelines for a group psycho-educational intervention. The results of the study indicated a struggling psychological profile. This was defined as the ability to deal with work-related stressors – but with the potential risk of developing symptoms of burnout. The moderate levels of resilience were attributed to elevated character strengths in the sample. The distribution of personality traits indicated that the nurses in the sample were at risk of developing burnout; and this prevented them from flourishing. These data were synthesised to create therapeutic guidelines for developing resilience aimed: (1) increasing emotional stability and invulnerability; (2) increasing agreeableness; and (3) increasing conscientiousness. These guidelines were based on the personality traits that were deemed to negatively impact the resilience of the nurses. These personality traits were correlated with several character strengths that displayed strong relationships with resilience. This indicated that resilience could be developed through the cultivation of the following character strengths: perspective; perseverance; fairness; forgiveness; leadership; love; zest; hope; curiosity; and appreciation of beauty and excellence. These character strengths were identified to facilitate the positive adaptation of the personality traits identified in the therapeutic guidelines. A group psycho-educational intervention was developed, using the positive clinical psychology conceptualisation of resilience. The literature was reviewed to identify techniques to cultivate the ten character strengths specified in the therapeutic guidelines. These techniques were adapted to create experiential learning processes for the intervention. This psycho-educational programme can be applied as a secondary and tertiary intervention. It can be used to increase resilience to prevent burnout among nurses. It can also be used to psychologically empower nurses that have existing symptoms of burnout.
- Full Text:
- Date Issued: 2015
- Authors: Plumb, Sarah
- Date: 2015
- Subjects: Nurses -- Job stress , Nursing -- Psychological aspects , Resilience (Personality trait)
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9955 , http://hdl.handle.net/10948/d1018879
- Description: Nurses are confronted with numerous work-related stressors that can result in burnout. This can contribute to absenteeism and high turn-over rates in the nursing profession. A review of the literature indicated that psycho-educational interventions to increase resilience could be an effective way of addressing this problem. The study aimed to develop a positive clinical-psychology approach to increasing resilience in State employed nurses. The study used a mixed-method approach to determine the current psychological functioning of a sample of 87 nurses. Quantitative data on personality traits, character strengths and levels of resilience were obtained, using the NEO PI-R, VIA – IS, and Resilience Scale. Qualitative data on the coping responses of nurses were obtained through the thematic analysis of focus groups. These data were integrated to create a positive clinical psychology conceptualisation of resilience and to develop therapeutic guidelines for a group psycho-educational intervention. The results of the study indicated a struggling psychological profile. This was defined as the ability to deal with work-related stressors – but with the potential risk of developing symptoms of burnout. The moderate levels of resilience were attributed to elevated character strengths in the sample. The distribution of personality traits indicated that the nurses in the sample were at risk of developing burnout; and this prevented them from flourishing. These data were synthesised to create therapeutic guidelines for developing resilience aimed: (1) increasing emotional stability and invulnerability; (2) increasing agreeableness; and (3) increasing conscientiousness. These guidelines were based on the personality traits that were deemed to negatively impact the resilience of the nurses. These personality traits were correlated with several character strengths that displayed strong relationships with resilience. This indicated that resilience could be developed through the cultivation of the following character strengths: perspective; perseverance; fairness; forgiveness; leadership; love; zest; hope; curiosity; and appreciation of beauty and excellence. These character strengths were identified to facilitate the positive adaptation of the personality traits identified in the therapeutic guidelines. A group psycho-educational intervention was developed, using the positive clinical psychology conceptualisation of resilience. The literature was reviewed to identify techniques to cultivate the ten character strengths specified in the therapeutic guidelines. These techniques were adapted to create experiential learning processes for the intervention. This psycho-educational programme can be applied as a secondary and tertiary intervention. It can be used to increase resilience to prevent burnout among nurses. It can also be used to psychologically empower nurses that have existing symptoms of burnout.
- Full Text:
- Date Issued: 2015
The impact of government support on growth, survival and performance of cooperatives in selected areas of Eastern Cape province; South Africa
- Authors: Mqaba, Mzuyanda Victor
- Date: 2015
- Subjects: Cooperative societies -- South Africa -- Eastern Cape Producer cooperatives -- South Africa -- Eastern Cape Agriculture, Cooperative -- South Africa -- Eastern Cape Sustainable development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Com (Business Management)
- Identifier: http://hdl.handle.net/10353/1612 , vital:27488
- Description: This study investigated the impact of government support on growth, survival and performance of agricultural cooperatives in selected areas of Eastern Cape Province of South Africa. The objectives of this empirical study were to examine (1) the impact of government support on growth of cooperatives, (2) assess the impact of government support on the performance of cooperatives, (3) reviewing the impact of government support on survival of cooperatives. A total sample of 157 agricultural cooperatives which consisted of poultry, maize, goat, nursery, sheep and vegetable coops was used. Stratified random sampling technique was used and a self-administered questionnaire used to gather primary data. The primary data of the study was gathered from the cooperatives managers only as they were the targeted respondents. Gathered data went through factor analysis, anova test and correlation analysis for the statistical analysis purposefully to arrive in study findings and conclusion. The findings of the study drawn from the 66% response rate concluded that government support has a statistical significant impact on growth of cooperatives. The study also indicated that government support has a significant impact on the survival of cooperatives. It is also reported that the performance of cooperatives is significantly impacted positively by government support. The findings of the study also indicated that agricultural cooperatives are not satisfied with the present government support.
- Full Text:
- Date Issued: 2015
- Authors: Mqaba, Mzuyanda Victor
- Date: 2015
- Subjects: Cooperative societies -- South Africa -- Eastern Cape Producer cooperatives -- South Africa -- Eastern Cape Agriculture, Cooperative -- South Africa -- Eastern Cape Sustainable development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Com (Business Management)
- Identifier: http://hdl.handle.net/10353/1612 , vital:27488
- Description: This study investigated the impact of government support on growth, survival and performance of agricultural cooperatives in selected areas of Eastern Cape Province of South Africa. The objectives of this empirical study were to examine (1) the impact of government support on growth of cooperatives, (2) assess the impact of government support on the performance of cooperatives, (3) reviewing the impact of government support on survival of cooperatives. A total sample of 157 agricultural cooperatives which consisted of poultry, maize, goat, nursery, sheep and vegetable coops was used. Stratified random sampling technique was used and a self-administered questionnaire used to gather primary data. The primary data of the study was gathered from the cooperatives managers only as they were the targeted respondents. Gathered data went through factor analysis, anova test and correlation analysis for the statistical analysis purposefully to arrive in study findings and conclusion. The findings of the study drawn from the 66% response rate concluded that government support has a statistical significant impact on growth of cooperatives. The study also indicated that government support has a significant impact on the survival of cooperatives. It is also reported that the performance of cooperatives is significantly impacted positively by government support. The findings of the study also indicated that agricultural cooperatives are not satisfied with the present government support.
- Full Text:
- Date Issued: 2015
Plasmodium falciparum Hop: detailed analysis on complex formation with Hsp70 and Hsp90
- Hatherley, Rowan, Clitheroe, Crystal-Leigh, Faya, Ngonidzashe, Tastan Bishop, Özlem
- Authors: Hatherley, Rowan , Clitheroe, Crystal-Leigh , Faya, Ngonidzashe , Tastan Bishop, Özlem
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/163532 , vital:41046 , https://doi.org/10.1016/j.bbrc.2014.11.103
- Description: The heat shock organizing protein (Hop) is important in modulating the activity and co-interaction of two chaperones: heat shock protein 70 and 90 (Hsp70 and Hsp90). Recent research suggested that Plasmodium falciparum Hop (PfHop), PfHsp70 and PfHsp90 form a complex in the trophozoite infective stage. However, there has been little computational research on the malarial Hop protein in complex with other malarial Hsps.
- Full Text:
- Date Issued: 2015
- Authors: Hatherley, Rowan , Clitheroe, Crystal-Leigh , Faya, Ngonidzashe , Tastan Bishop, Özlem
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/163532 , vital:41046 , https://doi.org/10.1016/j.bbrc.2014.11.103
- Description: The heat shock organizing protein (Hop) is important in modulating the activity and co-interaction of two chaperones: heat shock protein 70 and 90 (Hsp70 and Hsp90). Recent research suggested that Plasmodium falciparum Hop (PfHop), PfHsp70 and PfHsp90 form a complex in the trophozoite infective stage. However, there has been little computational research on the malarial Hop protein in complex with other malarial Hsps.
- Full Text:
- Date Issued: 2015
Recycling as a strategy for environmental management in Cofimvaba
- Authors: Mniki, Yolisa Helen
- Date: 2015
- Subjects: Community development -- South Africa -- Eastern Cape Recycling (Waste, etc.) -- South Africa -- Eastern Cape Environmental management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/12614 , vital:27099
- Description: The success or failure of a local municipality is measured by the efficient provision of basic services to communities within the area of jurisdiction. Waste management is one of the basic services that pose serious environmental challenges. Various strategies have been developed as a means of waste management and recycling is a popular strategy as it has the potential to foster relations between the municipality and the community. Studies by the Department of environmental Affairs have confirmed that the delivery of waste management services by municipalities has capacity constraints including, but not limited to, landfill site operations, waste collection, processing and disposal, and waste management hierarchy (Department of Environmental Affairs, 2008). This research is undertaken to establish how recycling can be effective in environmental management. The findings emphasise strongly, the high level of awareness that communities have on recycling; however there is a need for intensive resource support for the community initiatives to have the desired impact.
- Full Text:
- Date Issued: 2015
- Authors: Mniki, Yolisa Helen
- Date: 2015
- Subjects: Community development -- South Africa -- Eastern Cape Recycling (Waste, etc.) -- South Africa -- Eastern Cape Environmental management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/12614 , vital:27099
- Description: The success or failure of a local municipality is measured by the efficient provision of basic services to communities within the area of jurisdiction. Waste management is one of the basic services that pose serious environmental challenges. Various strategies have been developed as a means of waste management and recycling is a popular strategy as it has the potential to foster relations between the municipality and the community. Studies by the Department of environmental Affairs have confirmed that the delivery of waste management services by municipalities has capacity constraints including, but not limited to, landfill site operations, waste collection, processing and disposal, and waste management hierarchy (Department of Environmental Affairs, 2008). This research is undertaken to establish how recycling can be effective in environmental management. The findings emphasise strongly, the high level of awareness that communities have on recycling; however there is a need for intensive resource support for the community initiatives to have the desired impact.
- Full Text:
- Date Issued: 2015
Development of high performance computing cluster for evaluation of sequence alignment algorithms
- Authors: Ngxande, Mkhuseli
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11399 , http://hdl.handle.net/10353/d1020163
- Description: As the biological databases are increasing rapidly, there is a challenge for both Biologists and Computer Scientists to develop algorithms and databases to manage the increasing data. There are many algorithms developed to align the sequences stored in biological databases - some take time to process the data while others are inefficient to produce reasonable results. As more data is generated, and time consuming algorithms are developed to handle them, there is a need for specialized computers to handle the computations. Researchers are typically limited by the computational power of their computers. High Performance Computing (HPC) field addresses this challenge and can be used in a cost-effective manner where there is no need for expensive equipment, instead old computers can be used together to form a powerful system. This is the premise of this research, wherein the setup of a low-cost Beowulf cluster is explored, with the subsequent evaluation of its performance for processing sequent alignment algorithms. A mixed method methodology is used in this dissertation, which consists of literature study, theoretical and practise based system. This mixed method methodology also have a proof and concept where the Beowulf cluster is designed and implemented to perform the sequence alignment algorithms and also the performance test. This dissertation firstly gives an overview of sequence alignment algorithms that are already developed and also highlights their timeline. A presentation of the design and implementation of the Beowulf Cluster is highlighted and this is followed by the experiments on the baseline performance of the cluster. A detailed timeline of the sequence alignment algorithms is given and also the comparison between ClustalW-MPI and T-Coffee (Tree-based Consistency Objective Function For alignment Evaluation) algorithm is presented as part of the findings in the research study. The efficiency of the cluster was observed to be 19.8%, this percentage is unexpected because the predicted efficiency is 83.3%, which is found in the theoretical cluster calculator. The theoretical performance of the cluster showed a high performance as compared with the experimental performance, this is attributable to the slow network, which was 100Mbps, low processor speed of 2.50 GHz, and low memory of 2 Gigabytes.
- Full Text:
- Date Issued: 2015
- Authors: Ngxande, Mkhuseli
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11399 , http://hdl.handle.net/10353/d1020163
- Description: As the biological databases are increasing rapidly, there is a challenge for both Biologists and Computer Scientists to develop algorithms and databases to manage the increasing data. There are many algorithms developed to align the sequences stored in biological databases - some take time to process the data while others are inefficient to produce reasonable results. As more data is generated, and time consuming algorithms are developed to handle them, there is a need for specialized computers to handle the computations. Researchers are typically limited by the computational power of their computers. High Performance Computing (HPC) field addresses this challenge and can be used in a cost-effective manner where there is no need for expensive equipment, instead old computers can be used together to form a powerful system. This is the premise of this research, wherein the setup of a low-cost Beowulf cluster is explored, with the subsequent evaluation of its performance for processing sequent alignment algorithms. A mixed method methodology is used in this dissertation, which consists of literature study, theoretical and practise based system. This mixed method methodology also have a proof and concept where the Beowulf cluster is designed and implemented to perform the sequence alignment algorithms and also the performance test. This dissertation firstly gives an overview of sequence alignment algorithms that are already developed and also highlights their timeline. A presentation of the design and implementation of the Beowulf Cluster is highlighted and this is followed by the experiments on the baseline performance of the cluster. A detailed timeline of the sequence alignment algorithms is given and also the comparison between ClustalW-MPI and T-Coffee (Tree-based Consistency Objective Function For alignment Evaluation) algorithm is presented as part of the findings in the research study. The efficiency of the cluster was observed to be 19.8%, this percentage is unexpected because the predicted efficiency is 83.3%, which is found in the theoretical cluster calculator. The theoretical performance of the cluster showed a high performance as compared with the experimental performance, this is attributable to the slow network, which was 100Mbps, low processor speed of 2.50 GHz, and low memory of 2 Gigabytes.
- Full Text:
- Date Issued: 2015
Hydrothermal co-liquefaction of microalgae biomass and coal
- Authors: Charlie, David
- Date: 2015
- Subjects: Microalgae -- Biotechnology Biomass chemicals , Biomass energy
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/50087 , vital:42035
- Description: In this research, the objective was to investigate under the chosen liquefaction conditions whether co-liquefaction of coal and microalgae biomass as agglomerates does possess a distinct advantage over the individual liquefaction of microalgae and coal. This was initially done by preparing dry micro algal biomass, followed by the preparation of coal fines and finally coal-algae as agglomerates. The agglomerates were prepared by continuously adsorbing wet concentrated microalgae slurry/solution onto the dry coal fines in order to prepare different ratios of coal-algae agglomerate(s). Ultimate analysis of the starting material (coal fines and the microalgae) as well the agglomerates then followed. According to research, wet microalgae biomass has the potential of acting as a hydrogen donor. By preparing the agglomerates, the rationale was to promote hydrogen supply from the micro algal biomass that has high hydrogen content to the coal with lower hydrogen content. The resulting product was then expected to have fairly higher hydrogen content. However, this was not observed or evident from the elemental analysis results. The results (elemental composition) showed no difference between the agglomerates and the coal. Based on the observed ultimate analysis results, liquefaction experiments were conducted to determine whether hydrogen transfer and the expected synergistic effect between micro algal biomass and coal would occur. The crude oil product was recovered and simulated distillation technique was used for the characterization of the crude oil product. The results we in agreement that higher yields can be achieved during co-liquefaction as compared to the individual liquefaction. A possible synergistic effect that was investigated in this research existed. Liquefaction results provided evidence of higher yields recovery from the agglomerates compared to those of coal fines and microalgae biomass. Although there was higher recovery on the agglomerates, there appears to be a downward trend (decrease) in product recovery with higher loadings of micro algal biomass on to the coal. This means that higher loading of micro algal biomass tend to suppress liquefaction of coal, thus resulting in lower product recovery. While lower loadings tend to effectively facilitate the liquefaction of coal, thus proving that the proposed synergistic effect between the two does exist. Overall product recovery (yields) of the agglomerates is higher compared to the individual recovery of coal fines and microalgae biomass. This was followed by mass balancing to determine the overall conversion. Higher conversions were achieved on the agglomerates compared to coal. This could mean that microalgae have the potential to facilitate the liquefaction of coal and improve its conversion. The observed trend results in improved conversion as well as higher oil yields (simulated distillation results). Overall, the mass balancing provided insightful information regarding the coal-microalgae interaction based on the conversion, and this further corresponds or supports the simulated distillation results. This research paper provides evidence of the synergistic effect that exists between micro algal biomass and coal.
- Full Text:
- Date Issued: 2015
- Authors: Charlie, David
- Date: 2015
- Subjects: Microalgae -- Biotechnology Biomass chemicals , Biomass energy
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/50087 , vital:42035
- Description: In this research, the objective was to investigate under the chosen liquefaction conditions whether co-liquefaction of coal and microalgae biomass as agglomerates does possess a distinct advantage over the individual liquefaction of microalgae and coal. This was initially done by preparing dry micro algal biomass, followed by the preparation of coal fines and finally coal-algae as agglomerates. The agglomerates were prepared by continuously adsorbing wet concentrated microalgae slurry/solution onto the dry coal fines in order to prepare different ratios of coal-algae agglomerate(s). Ultimate analysis of the starting material (coal fines and the microalgae) as well the agglomerates then followed. According to research, wet microalgae biomass has the potential of acting as a hydrogen donor. By preparing the agglomerates, the rationale was to promote hydrogen supply from the micro algal biomass that has high hydrogen content to the coal with lower hydrogen content. The resulting product was then expected to have fairly higher hydrogen content. However, this was not observed or evident from the elemental analysis results. The results (elemental composition) showed no difference between the agglomerates and the coal. Based on the observed ultimate analysis results, liquefaction experiments were conducted to determine whether hydrogen transfer and the expected synergistic effect between micro algal biomass and coal would occur. The crude oil product was recovered and simulated distillation technique was used for the characterization of the crude oil product. The results we in agreement that higher yields can be achieved during co-liquefaction as compared to the individual liquefaction. A possible synergistic effect that was investigated in this research existed. Liquefaction results provided evidence of higher yields recovery from the agglomerates compared to those of coal fines and microalgae biomass. Although there was higher recovery on the agglomerates, there appears to be a downward trend (decrease) in product recovery with higher loadings of micro algal biomass on to the coal. This means that higher loading of micro algal biomass tend to suppress liquefaction of coal, thus resulting in lower product recovery. While lower loadings tend to effectively facilitate the liquefaction of coal, thus proving that the proposed synergistic effect between the two does exist. Overall product recovery (yields) of the agglomerates is higher compared to the individual recovery of coal fines and microalgae biomass. This was followed by mass balancing to determine the overall conversion. Higher conversions were achieved on the agglomerates compared to coal. This could mean that microalgae have the potential to facilitate the liquefaction of coal and improve its conversion. The observed trend results in improved conversion as well as higher oil yields (simulated distillation results). Overall, the mass balancing provided insightful information regarding the coal-microalgae interaction based on the conversion, and this further corresponds or supports the simulated distillation results. This research paper provides evidence of the synergistic effect that exists between micro algal biomass and coal.
- Full Text:
- Date Issued: 2015
Thabisa addressing family
- Miss Thabisa and Dr McChonnachie
- Authors: Miss Thabisa and Dr McChonnachie
- Date: 2015
- Subjects: UNCATALOGUED
- Type: Image
- Identifier: http://hdl.handle.net/10962/220004 , vital:48582 , KHP-177
- Description: Miss Thabisa saying something to the family , Use of this resource is governed by the terms and conditions of the Creative Commons "Attribution-NonCommercial-ShareAlike" License (http://creativecommons.org/licenses/by-nc-sa/2.0/) (NEVER CAHNGE THIS FIELD)
- Full Text: false
- Date Issued: 2015
- Authors: Miss Thabisa and Dr McChonnachie
- Date: 2015
- Subjects: UNCATALOGUED
- Type: Image
- Identifier: http://hdl.handle.net/10962/220004 , vital:48582 , KHP-177
- Description: Miss Thabisa saying something to the family , Use of this resource is governed by the terms and conditions of the Creative Commons "Attribution-NonCommercial-ShareAlike" License (http://creativecommons.org/licenses/by-nc-sa/2.0/) (NEVER CAHNGE THIS FIELD)
- Full Text: false
- Date Issued: 2015
Editorial. Perspectives on transformations in learning and education
- Authors: Lotz-Sisitka, Heila
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/387277 , vital:68221 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/137656"
- Description: Perspectives on transformations in learning and education
- Full Text:
- Date Issued: 2015
- Authors: Lotz-Sisitka, Heila
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/387277 , vital:68221 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/137656"
- Description: Perspectives on transformations in learning and education
- Full Text:
- Date Issued: 2015
Perceptions of indigenous people regarding mental illness at Cacadu District in the Eastern Cape Province of South Africa
- Authors: Tilolo, Lwazi Romeo
- Date: 2015
- Subjects: Indigenous peoples -- Mental health -- South Africa -- Eastern Cape Cultural psychiatry -- South Africa -- Eastern Cape Healers -- South Africa -- Eastern Cape , Ethnopsychology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2677 , vital:27983
- Description: Indigenous people tend to consult traditional healers when a family member manifests change in behaviour, whilst conventional treatment disregards spirituality when preserving mental health. The aim of the study was to explore the perceptions of indigenous people and the role of traditional healers in the management of mentally ill persons within the Cacadu District in the Eastern Cape Province of South Africa. The study has adopted a qualitative approach which was exploratory and descriptive in nature. The sample consisted of nine relatives of mental health care users (MHCUs) and six traditional healers. Ethical principles were also taken into consideration by the researcher during the process of conducting the study. Data were collected from two strata, namely, relatives of the MHCUs and the traditional healers and an interview guide was used to conduct in-depth face-to-face interviews. Data were analysed using Tesch’s method of data analysis. Four themes emerged from the data categories and sub categories were identified. According to the themes participants indicated the negative impact of mental illness; as a result they portrayed great desperation regarding the means of accessing a cure for mental illness. Some participants showed insufficient knowledge regarding mental illness and had different perceptions and beliefs regarding the origin of mental illness. Available literature was used to emphasise and support the views that were expressed by both traditional healers and relatives of MHCUs. It has been highlighted from this study that indigenous people of Cacadu District view mental illness as spiritual in origin but they include Western medication for the benefit of the mentally ill. In addition, the relatives of the MHCUs highlighted the economic burden as the major problem that results from mental illness.
- Full Text:
- Date Issued: 2015
- Authors: Tilolo, Lwazi Romeo
- Date: 2015
- Subjects: Indigenous peoples -- Mental health -- South Africa -- Eastern Cape Cultural psychiatry -- South Africa -- Eastern Cape Healers -- South Africa -- Eastern Cape , Ethnopsychology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2677 , vital:27983
- Description: Indigenous people tend to consult traditional healers when a family member manifests change in behaviour, whilst conventional treatment disregards spirituality when preserving mental health. The aim of the study was to explore the perceptions of indigenous people and the role of traditional healers in the management of mentally ill persons within the Cacadu District in the Eastern Cape Province of South Africa. The study has adopted a qualitative approach which was exploratory and descriptive in nature. The sample consisted of nine relatives of mental health care users (MHCUs) and six traditional healers. Ethical principles were also taken into consideration by the researcher during the process of conducting the study. Data were collected from two strata, namely, relatives of the MHCUs and the traditional healers and an interview guide was used to conduct in-depth face-to-face interviews. Data were analysed using Tesch’s method of data analysis. Four themes emerged from the data categories and sub categories were identified. According to the themes participants indicated the negative impact of mental illness; as a result they portrayed great desperation regarding the means of accessing a cure for mental illness. Some participants showed insufficient knowledge regarding mental illness and had different perceptions and beliefs regarding the origin of mental illness. Available literature was used to emphasise and support the views that were expressed by both traditional healers and relatives of MHCUs. It has been highlighted from this study that indigenous people of Cacadu District view mental illness as spiritual in origin but they include Western medication for the benefit of the mentally ill. In addition, the relatives of the MHCUs highlighted the economic burden as the major problem that results from mental illness.
- Full Text:
- Date Issued: 2015