A role for heat shock protein 90 (Hsp90) in fibronectin matrix dynamics
- Authors: O'Hagan, Kyle Leonard
- Date: 2013
- Subjects: Molecular chaperones , Heat shock proteins , Metastasis , Cancer -- Treatment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4157 , http://hdl.handle.net/10962/d1018260
- Description: To date, a significant portion of research has been devoted to understanding the biological role of the molecular chaperone, heat shock protein 90 (Hsp90), in cancer development and metastasis. Studies have alluded to over 300 clients for intracellular Hsp90, many of which are involved in oncogenic signaling pathways, making Hsp90 a bone fide drug target with several inhibitors already in clinical trials. In recent years, a limited number of extracellular Hsp90 clients have been elucidated with roles in cancer cell migration and invasion. Examples of such clients include matrix metalloproteinase-2 (MMP-2), LRP-1/CD91 and HER-2. Inhibition of extracellular Hsp90 using cellimpermeable inhibitors has been shown to reduce cancer cell migration and metastasis by a hitherto undefined mechanism. Using surface biotinylation and an enzyme linked immunosorbent assay, we provided evidence to support that Hsp90 was found extracellularly in cancers of different origin, cell type and malignancy. Next, we isolated extracellular Hsp90-containing complexes from MDA-MB-231 breast cancer cells using a cell impermeable crosslinker followed by immunoprecipitation and identified by mass spectrometry that the extracellular matrix protein, fibronectin, co-precipitated with Hsp90β. This interaction between Hsp90β and fibronectin was confirmed using pull down assays and surface plasmon resonance spectroscopy with the purified proteins. The ability of exogenous Hsp90β to increase the insoluble fibronectin matrix in Hs578T breast cancer cells indicated a role for Hsp90 in fibronectin matrix stability or fibrillogenesis. Hsp90 knockdown by RNA interference or inhibition with the small molecule inhibitor, novobiocin, resulted in a dose and time-dependent reduction of the extracellular fibronectin matrix. Furthermore, novobiocin was shown to cause the internalization of a fluorescently-labeled exogenous fibronectin matrix incorporated into the extracellular matrix by Hs578T cells. This suggested endocytosis as a possible mechanism for fibronectin turnover. This was supported by the colocalization of fibronectin with key vesicular trafficking markers (Rab-5 and LAMP-1) in small, intracellular vesicles. Furthermore, treatment with the vesicular trafficking inhibitor, methyl-β-cyclodextrin, resulted in a dose-dependent recovery in the extracellular fibronectin matrix following treatment with novobiocin. Taken together, these data provided the first evidence to suggest fibronectin as a new client of Hsp90 and that Hsp90 was involved in regulating extracellular fibronectin matrix dynamics.
- Full Text:
- Date Issued: 2013
- Authors: O'Hagan, Kyle Leonard
- Date: 2013
- Subjects: Molecular chaperones , Heat shock proteins , Metastasis , Cancer -- Treatment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4157 , http://hdl.handle.net/10962/d1018260
- Description: To date, a significant portion of research has been devoted to understanding the biological role of the molecular chaperone, heat shock protein 90 (Hsp90), in cancer development and metastasis. Studies have alluded to over 300 clients for intracellular Hsp90, many of which are involved in oncogenic signaling pathways, making Hsp90 a bone fide drug target with several inhibitors already in clinical trials. In recent years, a limited number of extracellular Hsp90 clients have been elucidated with roles in cancer cell migration and invasion. Examples of such clients include matrix metalloproteinase-2 (MMP-2), LRP-1/CD91 and HER-2. Inhibition of extracellular Hsp90 using cellimpermeable inhibitors has been shown to reduce cancer cell migration and metastasis by a hitherto undefined mechanism. Using surface biotinylation and an enzyme linked immunosorbent assay, we provided evidence to support that Hsp90 was found extracellularly in cancers of different origin, cell type and malignancy. Next, we isolated extracellular Hsp90-containing complexes from MDA-MB-231 breast cancer cells using a cell impermeable crosslinker followed by immunoprecipitation and identified by mass spectrometry that the extracellular matrix protein, fibronectin, co-precipitated with Hsp90β. This interaction between Hsp90β and fibronectin was confirmed using pull down assays and surface plasmon resonance spectroscopy with the purified proteins. The ability of exogenous Hsp90β to increase the insoluble fibronectin matrix in Hs578T breast cancer cells indicated a role for Hsp90 in fibronectin matrix stability or fibrillogenesis. Hsp90 knockdown by RNA interference or inhibition with the small molecule inhibitor, novobiocin, resulted in a dose and time-dependent reduction of the extracellular fibronectin matrix. Furthermore, novobiocin was shown to cause the internalization of a fluorescently-labeled exogenous fibronectin matrix incorporated into the extracellular matrix by Hs578T cells. This suggested endocytosis as a possible mechanism for fibronectin turnover. This was supported by the colocalization of fibronectin with key vesicular trafficking markers (Rab-5 and LAMP-1) in small, intracellular vesicles. Furthermore, treatment with the vesicular trafficking inhibitor, methyl-β-cyclodextrin, resulted in a dose-dependent recovery in the extracellular fibronectin matrix following treatment with novobiocin. Taken together, these data provided the first evidence to suggest fibronectin as a new client of Hsp90 and that Hsp90 was involved in regulating extracellular fibronectin matrix dynamics.
- Full Text:
- Date Issued: 2013
A small town in the early apartheid era: A history of Grahamstown 1946-1960 focusing on "White English" perspectives.
- Lancaster, Rupert Giles Swinburne
- Authors: Lancaster, Rupert Giles Swinburne
- Date: 2013
- Subjects: Grahamstown (South Africa) -- History -- 20th Century , Grahamstown (South Africa) -- Politics and government -- 20th century , Grahamstown (South Africa) -- Social conditions -- 20th Century , Grahamstown (South Africa) -- Economic conditions -- 20th Century , Grahamstown (South Africa) -- Social life and customs -- 20th Century , Apartheid -- South Africa , Whites -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2612 , http://hdl.handle.net/10962/d1013161
- Description: This Thesis examines the socio-political perceptions of Grahamstown, a small South African City, during the period 1946 to 1960. The ‘White English’ population of Grahamstown is the specific focus, as it formed the dominant social group during the period and consequently provided the majority of information for this work. During this period the majority of Grahamstowns ‘White English’ population thought of their City as holding many attractive features and experiences despite the slum-conditions and poverty that were rife in the Locations. During the British Royal Familie’s tour of the Union of South Africa in 1947, Grahamstown was one of the Cities visited. The loyalty that Grahamstown’s ‘White English’ citizens felt towards the Royal Family and the United Kingdom is explored in connection with the regard that ‘White English’ Grahamstown held for the 1820 Settlers. To highlight the Grahamstown City Council’s activities during this period five events are analysed: The Grahamstown Financial Crisis, The Grahamstown Housing Crisis, The Beer Hall Debate, The establishment of a Tuberculosis Hospital and the granting of Full University Status to Rhodes University College. It is shown, with regard to the politics of the period, that ‘White English’ Grahamstown, unequivocally supported the United Party and were vocally anti-Nationalist. The implementation of Apartheid policies within Grahamstown is explored, with specific focus placed upon the Group Areas Act. Finally the anti-republican sentiment espoused by ‘White English’ Grahamstown is reviewed.
- Full Text:
- Date Issued: 2013
- Authors: Lancaster, Rupert Giles Swinburne
- Date: 2013
- Subjects: Grahamstown (South Africa) -- History -- 20th Century , Grahamstown (South Africa) -- Politics and government -- 20th century , Grahamstown (South Africa) -- Social conditions -- 20th Century , Grahamstown (South Africa) -- Economic conditions -- 20th Century , Grahamstown (South Africa) -- Social life and customs -- 20th Century , Apartheid -- South Africa , Whites -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2612 , http://hdl.handle.net/10962/d1013161
- Description: This Thesis examines the socio-political perceptions of Grahamstown, a small South African City, during the period 1946 to 1960. The ‘White English’ population of Grahamstown is the specific focus, as it formed the dominant social group during the period and consequently provided the majority of information for this work. During this period the majority of Grahamstowns ‘White English’ population thought of their City as holding many attractive features and experiences despite the slum-conditions and poverty that were rife in the Locations. During the British Royal Familie’s tour of the Union of South Africa in 1947, Grahamstown was one of the Cities visited. The loyalty that Grahamstown’s ‘White English’ citizens felt towards the Royal Family and the United Kingdom is explored in connection with the regard that ‘White English’ Grahamstown held for the 1820 Settlers. To highlight the Grahamstown City Council’s activities during this period five events are analysed: The Grahamstown Financial Crisis, The Grahamstown Housing Crisis, The Beer Hall Debate, The establishment of a Tuberculosis Hospital and the granting of Full University Status to Rhodes University College. It is shown, with regard to the politics of the period, that ‘White English’ Grahamstown, unequivocally supported the United Party and were vocally anti-Nationalist. The implementation of Apartheid policies within Grahamstown is explored, with specific focus placed upon the Group Areas Act. Finally the anti-republican sentiment espoused by ‘White English’ Grahamstown is reviewed.
- Full Text:
- Date Issued: 2013
A social realist account of the tutorial system at the University of Johannesburg
- Authors: Layton, Delia Melanie
- Date: 2013
- Subjects: University of Johannesburg Education, Higher -- South Africa Tutors and tutoring -- South Africa College teaching -- South Africa Archer, Margaret Scotford College student development programs -- South Africa Social realism , Tutorial system
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1314 , http://hdl.handle.net/10962/d1001621
- Description: Using Margaret Archer’s social realist methodology, this study critically examines the construction of the tutorial system in several departments and faculties at the Auckland Park campus of the University of Johannesburg. The purpose of the study is to investigate the extent to which tutorials support the acquisition of programme and disciplinary epistemologies. Social realism calls for analytical dualism of ‘the people’ (agents) from ‘the parts’ (structure and culture). This requires the separate consideration of structures (social systems, rules, roles, practices, policies, institutions, and organisational structures like committees, units, departments, faculties), culture (ideologies, theories, beliefs and values as evidenced in discourses), and agency (people and their ability to act within and upon their own world in terms of their social roles and positions dependent on their ability to activate their emergent properties and powers). Through this investigation, an understanding was gained into how the emergent properties and powers contained within the material, ideational and agential elements helped to generate certain events and practices in the tutorial system. These generative mechanisms were examined to explore whether they enabled or constrained the construction of the tutorial system to provide epistemological access. The study shows that while many official policy documents construct the tutorial system as being an intervention to support academic success, particularly for first-years, there are some tensions within the document discourses, where, on the one hand, student success is constructed in terms of throughput numbers, or, on the other hand, as being about becoming a particular kind of person who is able to access and add to powerful knowledge. Furthermore, the study found that policies are not being consistently implemented. While certain key agents and actors, in the form of management, academics and tutors, were found to be able to overcome constraints and introduce innovative ways of enhancing access to target epistemologies, there is a need for consideration of structural and cultural constraints. For example, structures in the form of funding, venues and timetabling were found to constrain the tutorial system as did some of the discourses in the cultural domain: for example, in the form of certain dominant discourses around teaching and learning, beliefs about the purpose of the tutorial and the relationship between academics and the tutorial system. The study also found that the ontological aspects of ‘learning to be’ were not fore-grounded to any great extent in the ways in which the tutorial system was constructed. There needs to be more consideration of the ontological as well as the epistemological aspects of first-year study so as to take cognisance of the different learning needs of an increasingly diverse student body and to encourage the development of the student agency necessary for a deep engagement with the disciplinary epistemologies.
- Full Text:
- Date Issued: 2013
- Authors: Layton, Delia Melanie
- Date: 2013
- Subjects: University of Johannesburg Education, Higher -- South Africa Tutors and tutoring -- South Africa College teaching -- South Africa Archer, Margaret Scotford College student development programs -- South Africa Social realism , Tutorial system
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1314 , http://hdl.handle.net/10962/d1001621
- Description: Using Margaret Archer’s social realist methodology, this study critically examines the construction of the tutorial system in several departments and faculties at the Auckland Park campus of the University of Johannesburg. The purpose of the study is to investigate the extent to which tutorials support the acquisition of programme and disciplinary epistemologies. Social realism calls for analytical dualism of ‘the people’ (agents) from ‘the parts’ (structure and culture). This requires the separate consideration of structures (social systems, rules, roles, practices, policies, institutions, and organisational structures like committees, units, departments, faculties), culture (ideologies, theories, beliefs and values as evidenced in discourses), and agency (people and their ability to act within and upon their own world in terms of their social roles and positions dependent on their ability to activate their emergent properties and powers). Through this investigation, an understanding was gained into how the emergent properties and powers contained within the material, ideational and agential elements helped to generate certain events and practices in the tutorial system. These generative mechanisms were examined to explore whether they enabled or constrained the construction of the tutorial system to provide epistemological access. The study shows that while many official policy documents construct the tutorial system as being an intervention to support academic success, particularly for first-years, there are some tensions within the document discourses, where, on the one hand, student success is constructed in terms of throughput numbers, or, on the other hand, as being about becoming a particular kind of person who is able to access and add to powerful knowledge. Furthermore, the study found that policies are not being consistently implemented. While certain key agents and actors, in the form of management, academics and tutors, were found to be able to overcome constraints and introduce innovative ways of enhancing access to target epistemologies, there is a need for consideration of structural and cultural constraints. For example, structures in the form of funding, venues and timetabling were found to constrain the tutorial system as did some of the discourses in the cultural domain: for example, in the form of certain dominant discourses around teaching and learning, beliefs about the purpose of the tutorial and the relationship between academics and the tutorial system. The study also found that the ontological aspects of ‘learning to be’ were not fore-grounded to any great extent in the ways in which the tutorial system was constructed. There needs to be more consideration of the ontological as well as the epistemological aspects of first-year study so as to take cognisance of the different learning needs of an increasingly diverse student body and to encourage the development of the student agency necessary for a deep engagement with the disciplinary epistemologies.
- Full Text:
- Date Issued: 2013
A social realist analysis of learner agency and access to education : the case of Grade 11 learners in public secondary schools in the Makana District, Eastern Cape
- Authors: Namakula, Halima
- Date: 2013
- Subjects: Active learning -- Research -- South Africa -- Eastern Cape Educational equalization -- Research -- South Africa -- Eastern Cape Student-centered learning -- Research -- South Africa -- Eastern Cape Competency-based education -- South Africa -- Eastern Cape Education, Secondary -- Research -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1404 , http://hdl.handle.net/10962/d1001954
- Description: The South African government has shown enormous commitment to the achievement of “Education for All” (EFA) through its policies premised on the right to basic education for all which is enshrined in the constitution. Central to the South African constitution, is a fundamental right of all citizens to basic education, equity, redress, and the improvement of quality of schooling. Further, pro-poor funding policies such as school fee exemptions, social grants and, most recently, the designation of 60% of all schools as ‘no fee’ schools, have made it possible for even the poorest learners to attend school. This has affirmed South Africa’s commitment to the achievement of the Millennium Development Goals (MDGs) by 2015. In light of Notwithstanding the progress made in South Africa in universalising education, there are concerns regarding learner access to quality education, especially in poor provinces such as the Eastern Cape where this study is situated. Thus, the purpose of this study is to further understanding of the interface between learners’ agency and access to education in two township public high schools in Makana District in the Eastern Cape Province. In doing so, the research addresses the current under-representation in the literature of the voices of learners about their experiences of access to education. Drawing on Margaret Archer’s social realist approach to the relationship between structure and agency, the study explores learner agency with the aim of understanding how learners exercise their agency as they struggle to negotiate and overcome difficult and challenging circumstances in order to access education. The data collection was carried out during the academic year 2011, using a qualitative case study approach. Multiple methods of data collection were used. First, data was collected through questionnaires administered to learners. This questionnaire asked for basic information about the schools (for example, subjects, resources and teachers ), parents ( their education, employment, qualification etc.) and learners’ aspirations (their role model; where they see themselves in 5 years; which university they would like to attend; and what they would like to become in future). Secondly, observation method was used to collect data that would inform an assessment of the school’s structure and cultural practices and the impact these have on learners’ access to education. The focus here was also on classroom interaction between learners and teachers, as well as classroom participation, participation in extra-mural activities and voluntary activities, and interaction with peers and others in a variety of school settings. Thirdly, interviews with learners, educators, principals, and parents were used to provide insight about how participants construct their social worlds. In this study the primary data was collected through semi-structured individual and focus group interview. And finally, document analysis was used to analyse the attendance and performance of learners on attendance registers. Findings from this research have enabled new themes and areas for reflection about learner agency to emerge. These themes reflect current and ongoing constraints and enablements towards learners’ educational experiences. In particular, themes such as the following have surfaced: learners changing their lives; the desire to succeed; shaping the future; the value of education; family pride; aspirations and careers. This study addressed these developments by examining agency as temporally located reflexive deliberations of learners upon their future goals and present social environment. This allowed for the identification of individuals’ future goals in relation to access to education and the strategies that they intend to pursue to achieve them, in relation to their personal and social contexts. The findings show the choices and decisions learners are prepared to make and the strategies they use as they engage with socio-cultural environments. Archer’s nuanced approach to agency and structure offers tools to help make sense of learners’ equally nuanced way of engaging with various social structures and making considered decisions about their social environment. Key findings of this research suggest that despite the constraining social structures in their homes, communities and schools, learners make decisions and choices that enable them to navigate social contexts to their advantage. Put differently, for learners, social structures provided the impetus for the projects they created, and to this extent enabled rather than constrained their courses of action.
- Full Text:
- Date Issued: 2013
- Authors: Namakula, Halima
- Date: 2013
- Subjects: Active learning -- Research -- South Africa -- Eastern Cape Educational equalization -- Research -- South Africa -- Eastern Cape Student-centered learning -- Research -- South Africa -- Eastern Cape Competency-based education -- South Africa -- Eastern Cape Education, Secondary -- Research -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1404 , http://hdl.handle.net/10962/d1001954
- Description: The South African government has shown enormous commitment to the achievement of “Education for All” (EFA) through its policies premised on the right to basic education for all which is enshrined in the constitution. Central to the South African constitution, is a fundamental right of all citizens to basic education, equity, redress, and the improvement of quality of schooling. Further, pro-poor funding policies such as school fee exemptions, social grants and, most recently, the designation of 60% of all schools as ‘no fee’ schools, have made it possible for even the poorest learners to attend school. This has affirmed South Africa’s commitment to the achievement of the Millennium Development Goals (MDGs) by 2015. In light of Notwithstanding the progress made in South Africa in universalising education, there are concerns regarding learner access to quality education, especially in poor provinces such as the Eastern Cape where this study is situated. Thus, the purpose of this study is to further understanding of the interface between learners’ agency and access to education in two township public high schools in Makana District in the Eastern Cape Province. In doing so, the research addresses the current under-representation in the literature of the voices of learners about their experiences of access to education. Drawing on Margaret Archer’s social realist approach to the relationship between structure and agency, the study explores learner agency with the aim of understanding how learners exercise their agency as they struggle to negotiate and overcome difficult and challenging circumstances in order to access education. The data collection was carried out during the academic year 2011, using a qualitative case study approach. Multiple methods of data collection were used. First, data was collected through questionnaires administered to learners. This questionnaire asked for basic information about the schools (for example, subjects, resources and teachers ), parents ( their education, employment, qualification etc.) and learners’ aspirations (their role model; where they see themselves in 5 years; which university they would like to attend; and what they would like to become in future). Secondly, observation method was used to collect data that would inform an assessment of the school’s structure and cultural practices and the impact these have on learners’ access to education. The focus here was also on classroom interaction between learners and teachers, as well as classroom participation, participation in extra-mural activities and voluntary activities, and interaction with peers and others in a variety of school settings. Thirdly, interviews with learners, educators, principals, and parents were used to provide insight about how participants construct their social worlds. In this study the primary data was collected through semi-structured individual and focus group interview. And finally, document analysis was used to analyse the attendance and performance of learners on attendance registers. Findings from this research have enabled new themes and areas for reflection about learner agency to emerge. These themes reflect current and ongoing constraints and enablements towards learners’ educational experiences. In particular, themes such as the following have surfaced: learners changing their lives; the desire to succeed; shaping the future; the value of education; family pride; aspirations and careers. This study addressed these developments by examining agency as temporally located reflexive deliberations of learners upon their future goals and present social environment. This allowed for the identification of individuals’ future goals in relation to access to education and the strategies that they intend to pursue to achieve them, in relation to their personal and social contexts. The findings show the choices and decisions learners are prepared to make and the strategies they use as they engage with socio-cultural environments. Archer’s nuanced approach to agency and structure offers tools to help make sense of learners’ equally nuanced way of engaging with various social structures and making considered decisions about their social environment. Key findings of this research suggest that despite the constraining social structures in their homes, communities and schools, learners make decisions and choices that enable them to navigate social contexts to their advantage. Put differently, for learners, social structures provided the impetus for the projects they created, and to this extent enabled rather than constrained their courses of action.
- Full Text:
- Date Issued: 2013
A standardised protocol for roadkill detection and the determinants of roadkill in the greater Mapungubwe Transfrontier Conservation Area, Limpopo Province, South Africa
- Authors: Collinson, Wendy Jane
- Date: 2013
- Subjects: Roadkill -- South Africa -- Mapungubwe Site , Traffic safety and wildlife -- South Africa -- Mapungubwe Site
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5606 , http://hdl.handle.net/10962/d1002056 , Roadkill -- South Africa -- Mapungubwe Site , Traffic safety and wildlife -- South Africa -- Mapungubwe Site
- Description: Despite evidence suggesting that road traffic is a major threat to biodiversity loss, very little is known about its actual impact on wildlife populations in South Africa. Globally, road density and traffic volumes are increasing, and although huge budgets are devoted to the construction and upgrading of roads, there is little or no allocation to mitigation measures for protecting fauna in most countries, particularly Africa. Further, no global standardised protocol exists for the rapid assessment of roadkill or the most economical and efficient approach for assessing roadkill rates. Using vehicle field trials, the reliability of detecting artificially deployed roadkill was assessed. Roadkill detection rates decreased significantly at speeds >50 km/h and were also significantly influenced by light conditions (i.e. detection success was greater when the sun was high) and the position of the roadkill on the road (i.e. smaller roadkill on verges were often missed). These results suggest that roadkill sampling was most effective between 1.5 hours after dawn and 1.5 hours before dusk and that driving at slower speeds (<50 km.h⁻ₑ) was required to detect roadkill. This protocol was implemented across three ecological seasons on a 100 km paved road and a 20 km unpaved road in the Greater Mapungubwe Transfrontier Conservation Area, Limpopo Province, South Africa. Driven daily over a 120-day period (three periods consisting each of 40 days), a total of 1,027 roadkill were recorded. These comprised 162 species from all terrestrial vertebrate groups with birds being the most commonly encountered roadkill (50% of all incidents). The high numbers of vertebrates identified as roadkill suggests that road traffic could have potentially unsustainable impacts on wildlife populations and hence the biodiversity of the area. Seventeen variables were identified as possible determinants of roadkill occurrence with season, rainfall, minimum and maximum temperature, habitat type, grass height, grass density, fence type and vehicle type significantly influencing roadkill numbers. Significantly more roadkill were detected on the paved road (9.91/100km) than on the unpaved road (1.8/100km) probably because of greater traffic volumes and the increased speed that vehicles travelled on the paved road. Warmer temperatures and increased rainfall in the preceding 24 hours also increased road mortality numbers as animals tended to become more active during these times. Interestingly, more roadkill was detected in open roadside habitats compared to dense roadside habitats on both the paved and unpaved roads and when grass on the roadside verge was of intermediate height. Open habitat possibly may provide a natural corridor for wildlife which ultimately end up on the road. Roadkill numbers increased when certain other physical barriers, such as cattle fences, were present, probably because these barriers were more penetrable than electric fencing. A series of mitigation measures are proposed to reduce the impacts of roads on wildlife in South Africa. These mitigation measures highlight the need to address the balance between the development of a country’s transport infrastructure and the conservation of its fauna. It is important that research on the impacts of roads becomes standardised to enable robust statistical comparisons which will provide a greater understanding of the potential threats to vertebrate biodiversity
- Full Text:
- Date Issued: 2013
- Authors: Collinson, Wendy Jane
- Date: 2013
- Subjects: Roadkill -- South Africa -- Mapungubwe Site , Traffic safety and wildlife -- South Africa -- Mapungubwe Site
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5606 , http://hdl.handle.net/10962/d1002056 , Roadkill -- South Africa -- Mapungubwe Site , Traffic safety and wildlife -- South Africa -- Mapungubwe Site
- Description: Despite evidence suggesting that road traffic is a major threat to biodiversity loss, very little is known about its actual impact on wildlife populations in South Africa. Globally, road density and traffic volumes are increasing, and although huge budgets are devoted to the construction and upgrading of roads, there is little or no allocation to mitigation measures for protecting fauna in most countries, particularly Africa. Further, no global standardised protocol exists for the rapid assessment of roadkill or the most economical and efficient approach for assessing roadkill rates. Using vehicle field trials, the reliability of detecting artificially deployed roadkill was assessed. Roadkill detection rates decreased significantly at speeds >50 km/h and were also significantly influenced by light conditions (i.e. detection success was greater when the sun was high) and the position of the roadkill on the road (i.e. smaller roadkill on verges were often missed). These results suggest that roadkill sampling was most effective between 1.5 hours after dawn and 1.5 hours before dusk and that driving at slower speeds (<50 km.h⁻ₑ) was required to detect roadkill. This protocol was implemented across three ecological seasons on a 100 km paved road and a 20 km unpaved road in the Greater Mapungubwe Transfrontier Conservation Area, Limpopo Province, South Africa. Driven daily over a 120-day period (three periods consisting each of 40 days), a total of 1,027 roadkill were recorded. These comprised 162 species from all terrestrial vertebrate groups with birds being the most commonly encountered roadkill (50% of all incidents). The high numbers of vertebrates identified as roadkill suggests that road traffic could have potentially unsustainable impacts on wildlife populations and hence the biodiversity of the area. Seventeen variables were identified as possible determinants of roadkill occurrence with season, rainfall, minimum and maximum temperature, habitat type, grass height, grass density, fence type and vehicle type significantly influencing roadkill numbers. Significantly more roadkill were detected on the paved road (9.91/100km) than on the unpaved road (1.8/100km) probably because of greater traffic volumes and the increased speed that vehicles travelled on the paved road. Warmer temperatures and increased rainfall in the preceding 24 hours also increased road mortality numbers as animals tended to become more active during these times. Interestingly, more roadkill was detected in open roadside habitats compared to dense roadside habitats on both the paved and unpaved roads and when grass on the roadside verge was of intermediate height. Open habitat possibly may provide a natural corridor for wildlife which ultimately end up on the road. Roadkill numbers increased when certain other physical barriers, such as cattle fences, were present, probably because these barriers were more penetrable than electric fencing. A series of mitigation measures are proposed to reduce the impacts of roads on wildlife in South Africa. These mitigation measures highlight the need to address the balance between the development of a country’s transport infrastructure and the conservation of its fauna. It is important that research on the impacts of roads becomes standardised to enable robust statistical comparisons which will provide a greater understanding of the potential threats to vertebrate biodiversity
- Full Text:
- Date Issued: 2013
A study of electrospun nanofibers and diatomaceous earth materials for the extraction of alkaloids, flavonoids and aromatic amines in various matrices
- Mothibedi, Kediemetse (Kedimetse)
- Authors: Mothibedi, Kediemetse (Kedimetse)
- Date: 2013 , 2013-04-07
- Subjects: Nanofibers , Electrospinning , Sorbents , Extraction (Chemistry) , Alkaloids , Flavonoids , Amines , Matrices , Goldenseal , Ginkgo , Dyes and dyeing -- Chemistry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4288 , http://hdl.handle.net/10962/d1003052 , Nanofibers , Electrospinning , Sorbents , Extraction (Chemistry) , Alkaloids , Flavonoids , Amines , Matrices , Goldenseal , Ginkgo , Dyes and dyeing -- Chemistry
- Description: The thesis explored the use of different sorbent materials in solid phase extraction method development. The methods included the use of the polymeric Agilent Bond Elut Plexa solid phase extraction and electrospun polymer-silica composite sorbents for clean-up and preconcentration. Sample clean-up for alkaloids (hydrastine and berberine) in goldenseal, Hydrastis canadensis and flavonoids (quercetin, kaempferol and isorhamnetin) in Ginkgo biloba was achieved using Bond Elut Plexa SPE sorbent. Clean-up of flavonoids in Ginkgo biloba was also achieved using electrospun polymer-silica composite (polystyrene-silica, polyacrylonitrile-silica and nylon 6-silica) sorbents. All analysis of flavonoids and alkaloids was carried out using an Agilent 1200 Series HPLC coupled with a diode array detector. Good peak separation was achieved in less than 6 min employing an Agilent ZORBAX Eclipse Plus C18 column (4.6 x 75 mm, 3.5 μm) at 35⁰C. The mobile phases employed were 0.1% phosphoric acid/methanol gradient and 0.5% phosphoric acid/methanol (40:60) for alkaloids and flavonoids respectively. The calibration curves exhibited linearity up to 120 μg mL⁻¹ with correlation coefficients of more than 0.9980. The recoveries ranged from 73-109% with relative standard deviation of less than 5% for all analytes. Agilent Chem Elut supported liquid extraction was employed for the development of a sample preparation method for the determination of 24 banned aromatic amines from azo dyes in textile following the EU standard method EN 14362-1:2003 (E) and the Chinese standard method GB/T 17592-2006. The supported liquid extraction was effective in the extraction of the aromatic amines from textile (cotton, wool and polyester/cotton [80%:20%]). Most of the recoveries obtained were conforming to the minimum requirements set in the EN 14362-1:2003 (E) standard method and the relative standard deviations were less than 15%. Good peak separation was obtained within 70 min run time using the Agilent Zorbax SB-Phenyl column (4.6 mm x 250 mm, 5-micron) or the Agilent DB-35 MS (J & W) (30 m x 0.25 mm, 0.25 μm film thickness. It was demonstrated that the polymeric Agilent Bond Elut Plexa, electrospun nanofibers and diatomaceous earth were effective in extraction of alkaloids, flavonoids and aromatic amines in different matrices. The developed methods were simple, rapid and reproducible.
- Full Text:
- Date Issued: 2013
- Authors: Mothibedi, Kediemetse (Kedimetse)
- Date: 2013 , 2013-04-07
- Subjects: Nanofibers , Electrospinning , Sorbents , Extraction (Chemistry) , Alkaloids , Flavonoids , Amines , Matrices , Goldenseal , Ginkgo , Dyes and dyeing -- Chemistry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4288 , http://hdl.handle.net/10962/d1003052 , Nanofibers , Electrospinning , Sorbents , Extraction (Chemistry) , Alkaloids , Flavonoids , Amines , Matrices , Goldenseal , Ginkgo , Dyes and dyeing -- Chemistry
- Description: The thesis explored the use of different sorbent materials in solid phase extraction method development. The methods included the use of the polymeric Agilent Bond Elut Plexa solid phase extraction and electrospun polymer-silica composite sorbents for clean-up and preconcentration. Sample clean-up for alkaloids (hydrastine and berberine) in goldenseal, Hydrastis canadensis and flavonoids (quercetin, kaempferol and isorhamnetin) in Ginkgo biloba was achieved using Bond Elut Plexa SPE sorbent. Clean-up of flavonoids in Ginkgo biloba was also achieved using electrospun polymer-silica composite (polystyrene-silica, polyacrylonitrile-silica and nylon 6-silica) sorbents. All analysis of flavonoids and alkaloids was carried out using an Agilent 1200 Series HPLC coupled with a diode array detector. Good peak separation was achieved in less than 6 min employing an Agilent ZORBAX Eclipse Plus C18 column (4.6 x 75 mm, 3.5 μm) at 35⁰C. The mobile phases employed were 0.1% phosphoric acid/methanol gradient and 0.5% phosphoric acid/methanol (40:60) for alkaloids and flavonoids respectively. The calibration curves exhibited linearity up to 120 μg mL⁻¹ with correlation coefficients of more than 0.9980. The recoveries ranged from 73-109% with relative standard deviation of less than 5% for all analytes. Agilent Chem Elut supported liquid extraction was employed for the development of a sample preparation method for the determination of 24 banned aromatic amines from azo dyes in textile following the EU standard method EN 14362-1:2003 (E) and the Chinese standard method GB/T 17592-2006. The supported liquid extraction was effective in the extraction of the aromatic amines from textile (cotton, wool and polyester/cotton [80%:20%]). Most of the recoveries obtained were conforming to the minimum requirements set in the EN 14362-1:2003 (E) standard method and the relative standard deviations were less than 15%. Good peak separation was obtained within 70 min run time using the Agilent Zorbax SB-Phenyl column (4.6 mm x 250 mm, 5-micron) or the Agilent DB-35 MS (J & W) (30 m x 0.25 mm, 0.25 μm film thickness. It was demonstrated that the polymeric Agilent Bond Elut Plexa, electrospun nanofibers and diatomaceous earth were effective in extraction of alkaloids, flavonoids and aromatic amines in different matrices. The developed methods were simple, rapid and reproducible.
- Full Text:
- Date Issued: 2013
A study of maximum and minimum operators with applications to piecewise linear payoff functions
- Authors: Seedat, Ebrahim
- Date: 2013
- Subjects: Options (Finance) Piecewise linear topology Geometry, Affine Riesz spaces Lattice theory Algebra, Boolean Pricing , Max and min operators
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:931 , http://hdl.handle.net/10962/d1001457
- Description: The payoff functions of contingent claims (options) of one variable are prominent in Financial Economics and thus assume a fundamental role in option pricing theory. Some of these payoff functions are continuous, piecewise-defined and linear or affine. Such option payoff functions can be analysed in a useful way when they are represented in additive, Boolean normal, graphical and linear form. The issue of converting such payoff functions expressed in the additive, linear or graphical form into an equivalent Boolean normal form, has been considered by several authors for more than half-a-century to better-understand the role of such functions. One aspect of our study is to unify the foregoing different forms of representation, by creating algorithms that convert a payoff function expressed in graphical form into Boolean normal form and then into the additive form and vice versa. Applications of these algorithms are considered in a general theoretical sense and also in the context of specific option contracts wherever relevant. The use of these algorithms have yielded easy computation of the area enclosed by the graph of various functions using min and max operators in several ways, which, in our opinion, are important in option pricing. To summarise, this study effectively dealt with maximum and minimum operators from several perspectives
- Full Text:
- Date Issued: 2013
- Authors: Seedat, Ebrahim
- Date: 2013
- Subjects: Options (Finance) Piecewise linear topology Geometry, Affine Riesz spaces Lattice theory Algebra, Boolean Pricing , Max and min operators
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:931 , http://hdl.handle.net/10962/d1001457
- Description: The payoff functions of contingent claims (options) of one variable are prominent in Financial Economics and thus assume a fundamental role in option pricing theory. Some of these payoff functions are continuous, piecewise-defined and linear or affine. Such option payoff functions can be analysed in a useful way when they are represented in additive, Boolean normal, graphical and linear form. The issue of converting such payoff functions expressed in the additive, linear or graphical form into an equivalent Boolean normal form, has been considered by several authors for more than half-a-century to better-understand the role of such functions. One aspect of our study is to unify the foregoing different forms of representation, by creating algorithms that convert a payoff function expressed in graphical form into Boolean normal form and then into the additive form and vice versa. Applications of these algorithms are considered in a general theoretical sense and also in the context of specific option contracts wherever relevant. The use of these algorithms have yielded easy computation of the area enclosed by the graph of various functions using min and max operators in several ways, which, in our opinion, are important in option pricing. To summarise, this study effectively dealt with maximum and minimum operators from several perspectives
- Full Text:
- Date Issued: 2013
A study of the first group of Friars Minor (Franciscans) in South Africa, c. 1932-1960
- Authors: Nogemane, Vumile
- Date: 2013
- Subjects: Franciscans -- South Africa -- History
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2530 , http://hdl.handle.net/10962/d1001859
- Description: In 1932, six Missionary Franciscan Friars from Bavaria came to South Africa at the invitation of Bishop Adalbero Michael Fleischer (1874-1963), a Mariannhill missionary in Natal. His vision was that they would establish a “Franciscan Family” there. Despite this invitation, the Friars were not welcomed by the Mariannhill community and went on to found the Mount Currie Prefecture (Diocese of Kokstad) in 1935. There the Franciscans became involved in the life of the ordinary people, who were otherwise abandoned by the government. Among other activities, they provided schools and gardens, and embarked on skills development projects for the youth. The Holy Cross Sisters - whose arrival in 1926 pre-dated that of the Friars - played a crucial role in these developments. From 1952, their educational work would be supplemented by the medical work of the Franciscan Missionaries of Mary Sisters. The arrival of Irish Franciscans (1946) and English Franciscans (1948) brought tensions and differing interpretations of the form that the vision should take. In addition, the Friars were men of their times and products of their particular backgrounds. For example, while some saw their African converts as equals, others were prejudiced against them. However, this thesis – the work of an “insider” to the faith and to the Order, argues that despite tensions and shortcomings, the settlement, and continuing presence, of the Franciscan Friars and Sisters in the Eastern Cape was an eventual realization of Bishop Fleischer’s vision, even though in a slightly different manner from the original ideal. In the early nineteen sixties a new and powerful spirit invaded the Catholic Church. The Second Vatican Council took place from 1962 to 1965. It may be argued that, from that time onward, the Church has never been the same again. In accordance with this call and invitation of the Second Vatican Council for quite some time it has been my earnest desire to get down into a more in-depth study of the history of the Franciscans in South Africa than that provided by the two existing works on this topic. It is my hope that this thesis will contribute to a soul-searching of the Franciscans as they continue to live and minister to the people of South Africa. This history will hopefully teach us to learn from and be inspired by the great and heroic deeds of our spiritual forebears – our Franciscan brothers and sisters – and also teach us to learn from their mistakes.
- Full Text:
- Date Issued: 2013
- Authors: Nogemane, Vumile
- Date: 2013
- Subjects: Franciscans -- South Africa -- History
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2530 , http://hdl.handle.net/10962/d1001859
- Description: In 1932, six Missionary Franciscan Friars from Bavaria came to South Africa at the invitation of Bishop Adalbero Michael Fleischer (1874-1963), a Mariannhill missionary in Natal. His vision was that they would establish a “Franciscan Family” there. Despite this invitation, the Friars were not welcomed by the Mariannhill community and went on to found the Mount Currie Prefecture (Diocese of Kokstad) in 1935. There the Franciscans became involved in the life of the ordinary people, who were otherwise abandoned by the government. Among other activities, they provided schools and gardens, and embarked on skills development projects for the youth. The Holy Cross Sisters - whose arrival in 1926 pre-dated that of the Friars - played a crucial role in these developments. From 1952, their educational work would be supplemented by the medical work of the Franciscan Missionaries of Mary Sisters. The arrival of Irish Franciscans (1946) and English Franciscans (1948) brought tensions and differing interpretations of the form that the vision should take. In addition, the Friars were men of their times and products of their particular backgrounds. For example, while some saw their African converts as equals, others were prejudiced against them. However, this thesis – the work of an “insider” to the faith and to the Order, argues that despite tensions and shortcomings, the settlement, and continuing presence, of the Franciscan Friars and Sisters in the Eastern Cape was an eventual realization of Bishop Fleischer’s vision, even though in a slightly different manner from the original ideal. In the early nineteen sixties a new and powerful spirit invaded the Catholic Church. The Second Vatican Council took place from 1962 to 1965. It may be argued that, from that time onward, the Church has never been the same again. In accordance with this call and invitation of the Second Vatican Council for quite some time it has been my earnest desire to get down into a more in-depth study of the history of the Franciscans in South Africa than that provided by the two existing works on this topic. It is my hope that this thesis will contribute to a soul-searching of the Franciscans as they continue to live and minister to the people of South Africa. This history will hopefully teach us to learn from and be inspired by the great and heroic deeds of our spiritual forebears – our Franciscan brothers and sisters – and also teach us to learn from their mistakes.
- Full Text:
- Date Issued: 2013
A study of women's representation in relation to poverty: a case study of The Post March 2009
- Gwanvalla, Delphine Ngehndab
- Authors: Gwanvalla, Delphine Ngehndab
- Date: 2013
- Subjects: Journalism, Commercial -- Social aspects -- Cameroon Women -- Cameroon -- Social conditions Poor women -- Cameroon Mass media and women -- Cameroon
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3504 , http://hdl.handle.net/10962/d1007144
- Description: The media, specifically tabloids, have the potential to portray poverty-related issues in a manner that informs the public and government about the experiences of people living in poverty so that it can be tackled with urgency. Poverty has blighted the lives of many, especially women, children and widows in Cameroon. The role of the media in reporting the plight and suffering of the ‘masses’ potentially shapes the way in which these issues are handled by those in authority. The study notes that the tabloid press has the potential to expose certain experiences of ordinary people thereby constituting that alternative sphere for the disadvantaged. The study investigates the manner women are represented in The Post which is an English tabloid published in Cameroon. The representation of women in this study looks at the institutional policies which drive the representation of women in news constructs, analyses the news values which shape news production, and uses Thompson’s modes of ideology to unravel the underlying meanings in the reported stories. The study is inspired by the claims that since women make up the majority of the world's poor, so too would media representations depict them as such. It utilises thematic analysis to understand the manner in which women are represented in The Post. It also uses interviews with the regional bureau editor of the North West region to probe what news values and institutional policies drive the stories on women’s poverty. Document analysis is used to better comprehend the institutional guidelines which govern the representation of women during the month of March 2009.
- Full Text:
- Date Issued: 2013
- Authors: Gwanvalla, Delphine Ngehndab
- Date: 2013
- Subjects: Journalism, Commercial -- Social aspects -- Cameroon Women -- Cameroon -- Social conditions Poor women -- Cameroon Mass media and women -- Cameroon
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3504 , http://hdl.handle.net/10962/d1007144
- Description: The media, specifically tabloids, have the potential to portray poverty-related issues in a manner that informs the public and government about the experiences of people living in poverty so that it can be tackled with urgency. Poverty has blighted the lives of many, especially women, children and widows in Cameroon. The role of the media in reporting the plight and suffering of the ‘masses’ potentially shapes the way in which these issues are handled by those in authority. The study notes that the tabloid press has the potential to expose certain experiences of ordinary people thereby constituting that alternative sphere for the disadvantaged. The study investigates the manner women are represented in The Post which is an English tabloid published in Cameroon. The representation of women in this study looks at the institutional policies which drive the representation of women in news constructs, analyses the news values which shape news production, and uses Thompson’s modes of ideology to unravel the underlying meanings in the reported stories. The study is inspired by the claims that since women make up the majority of the world's poor, so too would media representations depict them as such. It utilises thematic analysis to understand the manner in which women are represented in The Post. It also uses interviews with the regional bureau editor of the North West region to probe what news values and institutional policies drive the stories on women’s poverty. Document analysis is used to better comprehend the institutional guidelines which govern the representation of women during the month of March 2009.
- Full Text:
- Date Issued: 2013
A systematic study of Berkheya and allies (Compositae)
- Authors: Phaliso, Ntombifikile
- Date: 2013
- Subjects: Compositae -- Africa, Southern , Daisies -- Africa, Southern , Compositae -- Phylogeny -- Africa, Southern , Compositae -- Geographical distribution -- Africa, Southern , Compositae -- Classification -- Africa, Southern , Cladistic analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4179 , http://hdl.handle.net/10962/d1003054
- Description: Berkheya Ehrh. is a genus of daisies in the tribe Arctotideae, subtribe Gorteriinae with over 80 species, most of which occur in southern Africa. This genus has centres of diversity associated with the montane regions of South Africa, including the Drakensberg Alpine Centre and Mpumalanga escarpment regions. Previous molecular and morphological studies indicate that Berkheya is paraphyletic. I present phylogenies based on nrDNA (ITS; Internal Transcribed Spacer) and cpDNA (psbA-trnH) sequence data analysed with Bayesian Inference and Parsimony. A phylogeny of combined cp- and nrDNA is also presented. These phylogenies are used to assess generic limits and to investigate the biogeographic patterns of Berkheya and its allies. The ITS phylogeny shows five well supported clades of Berkheya, two of which (Clades I and 2) are monophyletic summer rainfall region clades. Clades 3 to 5 are all paraphyletic winter rainfall clades with Cullumia occurring in the third clade, Cuspida occurring in the fourth and Didelta in Clade 5. Both psbA-trnH and combined phylogenies show concordance with the clade distribution shown in the ITS phylogeny. The ITS phylogeny was used to analyse correspondence with Roessler’s (1959) Series. It was found that the phylogeny showed considerable agreement with Roessler’s series, but B. bipinnatifida and B. spinosa of Series Speciosae may require some revision as well as taxa of monotypic series Cruciatae and Angustae. It is suggested that the latter series be merged with Cullumia species to form a single series. Some consideration should be taken to include Didelta species into Series Fruticosae as Didelta occurs in subclade 5b of Clade 5 with other Series Fruticosae taxa. Achene morphology was examined from species from each of the five clades to investigate the relationships of Berkheya and its allies, as well as to determine if there were any consistent achene features for each clade. The structure of surface cells on the fruit, the presence, absence and morphology of twin hairs as well as the structure of the pappus scales were found to be most useful in reflecting phylogenetic relationships within the clades. When compared with the clades of the ITS phylogeny, achene morphology showed consistent characters between taxa occurring in the same clades. As the most comprehensive study involving Berkheya, this phylogenenetic investigation was able to confirm that Berkheya is a paraphyletic genus with Didelta, Cullumia and Cuspida needing to be subsumed into Berkheya. An alternative classification is that taxa of Clade 5 could possibly be erected as an expanded Didelta, separate and sister to Berkheya.
- Full Text:
- Date Issued: 2013
- Authors: Phaliso, Ntombifikile
- Date: 2013
- Subjects: Compositae -- Africa, Southern , Daisies -- Africa, Southern , Compositae -- Phylogeny -- Africa, Southern , Compositae -- Geographical distribution -- Africa, Southern , Compositae -- Classification -- Africa, Southern , Cladistic analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4179 , http://hdl.handle.net/10962/d1003054
- Description: Berkheya Ehrh. is a genus of daisies in the tribe Arctotideae, subtribe Gorteriinae with over 80 species, most of which occur in southern Africa. This genus has centres of diversity associated with the montane regions of South Africa, including the Drakensberg Alpine Centre and Mpumalanga escarpment regions. Previous molecular and morphological studies indicate that Berkheya is paraphyletic. I present phylogenies based on nrDNA (ITS; Internal Transcribed Spacer) and cpDNA (psbA-trnH) sequence data analysed with Bayesian Inference and Parsimony. A phylogeny of combined cp- and nrDNA is also presented. These phylogenies are used to assess generic limits and to investigate the biogeographic patterns of Berkheya and its allies. The ITS phylogeny shows five well supported clades of Berkheya, two of which (Clades I and 2) are monophyletic summer rainfall region clades. Clades 3 to 5 are all paraphyletic winter rainfall clades with Cullumia occurring in the third clade, Cuspida occurring in the fourth and Didelta in Clade 5. Both psbA-trnH and combined phylogenies show concordance with the clade distribution shown in the ITS phylogeny. The ITS phylogeny was used to analyse correspondence with Roessler’s (1959) Series. It was found that the phylogeny showed considerable agreement with Roessler’s series, but B. bipinnatifida and B. spinosa of Series Speciosae may require some revision as well as taxa of monotypic series Cruciatae and Angustae. It is suggested that the latter series be merged with Cullumia species to form a single series. Some consideration should be taken to include Didelta species into Series Fruticosae as Didelta occurs in subclade 5b of Clade 5 with other Series Fruticosae taxa. Achene morphology was examined from species from each of the five clades to investigate the relationships of Berkheya and its allies, as well as to determine if there were any consistent achene features for each clade. The structure of surface cells on the fruit, the presence, absence and morphology of twin hairs as well as the structure of the pappus scales were found to be most useful in reflecting phylogenetic relationships within the clades. When compared with the clades of the ITS phylogeny, achene morphology showed consistent characters between taxa occurring in the same clades. As the most comprehensive study involving Berkheya, this phylogenenetic investigation was able to confirm that Berkheya is a paraphyletic genus with Didelta, Cullumia and Cuspida needing to be subsumed into Berkheya. An alternative classification is that taxa of Clade 5 could possibly be erected as an expanded Didelta, separate and sister to Berkheya.
- Full Text:
- Date Issued: 2013
A teaching case study of the strategic alignment of business strategy and information technology strategy at Nedbank
- Authors: Tsoaeli, Tebalo
- Date: 2013
- Subjects: Nedbank Banks and banking -- South Africa Business planning Information technology
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:720 , http://hdl.handle.net/10962/d1001883
- Description: In today’s business world, a lot of organizations are investing heavily in Information Technology (IT) in order to develop a competitive edge. According to Loukis, Sapounas and Milionis (2009:85) “firms all over the world make significant investments in IT aiming to increase their efficiency and effectiveness”. According to Cline and Guynes (2001:10), “during the last 30 years, IT has become an increasingly integral part of business operations”. Most of the times, organizations fail to get real value from the investments made in IT. This is mainly due to the fact that organizations fail to realize the value brought about by aligning IT strategy with Business strategy. Hu and Huang (2004:60) state that “each year organizations invest in IT to improve their competitive advantage and ultimately their business performance; however, more often than not, the anticipated benefits of IT investments fail to materialize due to misalignment of or lack of alignment, between the business and IT strategies”. Henderson and Venkatraman (1999:475) emphasize that “alignment is a desired state for organizations investing in IT that is not always achieved, as it often entails a radical change in the way managers consider IT”. It is through the alignment of IT strategy and Business strategy that organizations are able to realize the value brought about by investing in IT. Papp (2001:20)illustrates that “misalignment can cause problems with not only the development and integration of business and IT strategies, but can actually prevent IT from being fully leveraged to its maximum potential within an organization”. An organization that realizes the value of aligning IT strategy and Business strategy is able to develop a competitive advantage over its competitors. According to Daneshvar and Ramesh (2010:1) “each organization is aware of the special effects, benefits and implication of IT in business performance and also its capacity in building sustainable competitive advantages”.
- Full Text:
- Date Issued: 2013
- Authors: Tsoaeli, Tebalo
- Date: 2013
- Subjects: Nedbank Banks and banking -- South Africa Business planning Information technology
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:720 , http://hdl.handle.net/10962/d1001883
- Description: In today’s business world, a lot of organizations are investing heavily in Information Technology (IT) in order to develop a competitive edge. According to Loukis, Sapounas and Milionis (2009:85) “firms all over the world make significant investments in IT aiming to increase their efficiency and effectiveness”. According to Cline and Guynes (2001:10), “during the last 30 years, IT has become an increasingly integral part of business operations”. Most of the times, organizations fail to get real value from the investments made in IT. This is mainly due to the fact that organizations fail to realize the value brought about by aligning IT strategy with Business strategy. Hu and Huang (2004:60) state that “each year organizations invest in IT to improve their competitive advantage and ultimately their business performance; however, more often than not, the anticipated benefits of IT investments fail to materialize due to misalignment of or lack of alignment, between the business and IT strategies”. Henderson and Venkatraman (1999:475) emphasize that “alignment is a desired state for organizations investing in IT that is not always achieved, as it often entails a radical change in the way managers consider IT”. It is through the alignment of IT strategy and Business strategy that organizations are able to realize the value brought about by investing in IT. Papp (2001:20)illustrates that “misalignment can cause problems with not only the development and integration of business and IT strategies, but can actually prevent IT from being fully leveraged to its maximum potential within an organization”. An organization that realizes the value of aligning IT strategy and Business strategy is able to develop a competitive advantage over its competitors. According to Daneshvar and Ramesh (2010:1) “each organization is aware of the special effects, benefits and implication of IT in business performance and also its capacity in building sustainable competitive advantages”.
- Full Text:
- Date Issued: 2013
Afro-communitarianism and the nature of reconciliation
- Authors: Oelofsen, Rianna
- Date: 2013
- Subjects: Ubuntu (Philosophy) Reconciliation -- South Africa Communitarianism -- Africa Philosophy, African
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2736 , http://hdl.handle.net/10962/d1006809
- Description: In this dissertation I sketch a conception of personhood as understood from within an Afrocommunitarian worldview, and argue that this understanding of personhood has implications for understanding the concept of reconciliation. Understanding ‘being human’ as a collective, communal enterprise has implications for how responsibility, justice, forgiveness and humanization (all cognate concepts of reconciliation) are conceptualized. In line with this understanding of reconciliation and its cognate concepts, I argue that the humanization of self and other (according to the Afrocommunitarian understanding of personhood) is required for addressing the ‘inferiority’ and concurrent ‘superiority’ racial complexes as diagnosed by Franz Fanon and Steve Biko. These complexes reach deeply within individual and collective psyches and political identities, and I argue that political solutions to protracted conflict (in South Africa and other racially charged contexts) which do not address these deeply entrenched pathologies will be inadequate according to an Afrocommunitarian framework.
- Full Text:
- Date Issued: 2013
- Authors: Oelofsen, Rianna
- Date: 2013
- Subjects: Ubuntu (Philosophy) Reconciliation -- South Africa Communitarianism -- Africa Philosophy, African
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2736 , http://hdl.handle.net/10962/d1006809
- Description: In this dissertation I sketch a conception of personhood as understood from within an Afrocommunitarian worldview, and argue that this understanding of personhood has implications for understanding the concept of reconciliation. Understanding ‘being human’ as a collective, communal enterprise has implications for how responsibility, justice, forgiveness and humanization (all cognate concepts of reconciliation) are conceptualized. In line with this understanding of reconciliation and its cognate concepts, I argue that the humanization of self and other (according to the Afrocommunitarian understanding of personhood) is required for addressing the ‘inferiority’ and concurrent ‘superiority’ racial complexes as diagnosed by Franz Fanon and Steve Biko. These complexes reach deeply within individual and collective psyches and political identities, and I argue that political solutions to protracted conflict (in South Africa and other racially charged contexts) which do not address these deeply entrenched pathologies will be inadequate according to an Afrocommunitarian framework.
- Full Text:
- Date Issued: 2013
An analysis of regulatory mechanisms during sustained task execution in cognitive, motor and sensory tasks
- Tau, Sethunya Harriet Hlobisa
- Authors: Tau, Sethunya Harriet Hlobisa
- Date: 2013 , 2013-10-11
- Subjects: Work -- Physiological aspects , Work -- Psychological aspects , Fatigue , Attention , Mental fatigue , Human information processing , Decision making , Labor productivity , Employees -- Workload , Performance
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5140 , http://hdl.handle.net/10962/d1006806 , Work -- Physiological aspects , Work -- Psychological aspects , Fatigue , Attention , Mental fatigue , Human information processing , Decision making , Labor productivity , Employees -- Workload , Performance
- Description: Fatigue is a state that, although researched for many years, is still not completely understood. Alongside this lack of a general understanding of fatigue is a lack of knowledge on the processes involved in the regulation of fatigue. The existing theories relating to regulation are focussed on mental effort regulation, suggesting that performance outcomes are co-ordinated by effort regulation that functions by making alterations to physiological processes and strategic adjustments at a cognitive level in response to cognitive demands and goals. Since fatigue is a multi-dimensional construct with psychological, physiological, and behavioural effects that respond to endogenous and exogenous variables, it follows then that fatigue assessment techniques ought to include multi-dimensional measures to acquire a holistic depiction of the fatigue symptom. This study aimed to assess whether or not a mechanism that regulated fatigue during sustained task execution could be identified and whether this mechanism resulted in regulation patterns that were distinct to a specific task. An additional aim of the study was on assessing whether the manner in which performance, psychophysical and subjective variables were modified over time followed a similar regulation pattern. The research design was aimed at inducing task-related fatigue twice on two different occasions in the same participants and evaluating the resultant changes in fatigue manifestation. This was done to assess the ability of participants to cope with fatigue as a result of previous experience. The research protocol included three tasks executed for an hour aimed at targeting and taxing the sensory, cognitive, motor resources, each task performed twice. 60 participants were recruited to participate in the current study, with 20 participants – 10 males and 10 females – randomly assigned to each of the three tasks. The cognitive resource task consisted of a memory recall task relying on working memory intended to evaluate the extent of reductions in memory and attention. The sensory resource task consisted of a reading task measuring visual scanning and perception designed to evaluate the extent of reduced vigilance. The motor resource task consisted of a modified Fitts’ stimulus response task targeted at monitoring the extent of movement timing disruption. Performance measures comprised of: response delay and the number of correctly identified digits during the cognitive resource task, the amount of correctly identified errors and reading speed during the sensory resource task, response time during the motor resource task, and responses to simple auditory reaction time tests (RTT) initiated at intervals during the task and then again at the end of each task. Physiological measures included ear temperature, eye blink frequency and duration, heart rate (HR), and heart rate variability (HRV). Subjective measures included the use of the Ratings of Perceived Exertion Category Ratio 10 scale (RPE CR 10) to measure cognitive exertion and the NASA-Task Load Index (NASA-TLX) to index mental workload. Eye blink frequency and duration, HR and HRV were sensitive to the type of task executed, showing differing response patterns both over the different tasks and over the two test sessions. The subjective measures indicated increasing RPE ratings over time in all tasks while the NASA-TLX indicated that each task elicited different workloads. Differing task performance responses were measured between the 1st test session and the 2nd test session during all tasks; while performance was found to improve during the 2nd test session for the motor and sensory tasks, it declined during the cognitive task. The findings of this research indicate that there was a regulatory mechanism for fatigue that altered the manner in which performance, psychophysical and subjective variables were modified over time, initiating a unique fatigue regulation pattern for each variable and each task. This regulation mechanism is understood to be a proactive and protective mechanism that functions through reducing a person’s ability to be vigilant, attentive, to exercise discernment, and to direct their level of responsiveness, essentially impacting how the body adapts to and copes with fatigue. The noted overall findings have industry implications; industries should consider accounting for the effects of this regulatory mechanism in their fatigue management interventions, specifically when designing job rotation and work/rest schedules because each cognitive task, having elicited a unique fatigue regulation pattern, ought to also have a different management program. , Microsoft� Office Word 2007 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2013
- Authors: Tau, Sethunya Harriet Hlobisa
- Date: 2013 , 2013-10-11
- Subjects: Work -- Physiological aspects , Work -- Psychological aspects , Fatigue , Attention , Mental fatigue , Human information processing , Decision making , Labor productivity , Employees -- Workload , Performance
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5140 , http://hdl.handle.net/10962/d1006806 , Work -- Physiological aspects , Work -- Psychological aspects , Fatigue , Attention , Mental fatigue , Human information processing , Decision making , Labor productivity , Employees -- Workload , Performance
- Description: Fatigue is a state that, although researched for many years, is still not completely understood. Alongside this lack of a general understanding of fatigue is a lack of knowledge on the processes involved in the regulation of fatigue. The existing theories relating to regulation are focussed on mental effort regulation, suggesting that performance outcomes are co-ordinated by effort regulation that functions by making alterations to physiological processes and strategic adjustments at a cognitive level in response to cognitive demands and goals. Since fatigue is a multi-dimensional construct with psychological, physiological, and behavioural effects that respond to endogenous and exogenous variables, it follows then that fatigue assessment techniques ought to include multi-dimensional measures to acquire a holistic depiction of the fatigue symptom. This study aimed to assess whether or not a mechanism that regulated fatigue during sustained task execution could be identified and whether this mechanism resulted in regulation patterns that were distinct to a specific task. An additional aim of the study was on assessing whether the manner in which performance, psychophysical and subjective variables were modified over time followed a similar regulation pattern. The research design was aimed at inducing task-related fatigue twice on two different occasions in the same participants and evaluating the resultant changes in fatigue manifestation. This was done to assess the ability of participants to cope with fatigue as a result of previous experience. The research protocol included three tasks executed for an hour aimed at targeting and taxing the sensory, cognitive, motor resources, each task performed twice. 60 participants were recruited to participate in the current study, with 20 participants – 10 males and 10 females – randomly assigned to each of the three tasks. The cognitive resource task consisted of a memory recall task relying on working memory intended to evaluate the extent of reductions in memory and attention. The sensory resource task consisted of a reading task measuring visual scanning and perception designed to evaluate the extent of reduced vigilance. The motor resource task consisted of a modified Fitts’ stimulus response task targeted at monitoring the extent of movement timing disruption. Performance measures comprised of: response delay and the number of correctly identified digits during the cognitive resource task, the amount of correctly identified errors and reading speed during the sensory resource task, response time during the motor resource task, and responses to simple auditory reaction time tests (RTT) initiated at intervals during the task and then again at the end of each task. Physiological measures included ear temperature, eye blink frequency and duration, heart rate (HR), and heart rate variability (HRV). Subjective measures included the use of the Ratings of Perceived Exertion Category Ratio 10 scale (RPE CR 10) to measure cognitive exertion and the NASA-Task Load Index (NASA-TLX) to index mental workload. Eye blink frequency and duration, HR and HRV were sensitive to the type of task executed, showing differing response patterns both over the different tasks and over the two test sessions. The subjective measures indicated increasing RPE ratings over time in all tasks while the NASA-TLX indicated that each task elicited different workloads. Differing task performance responses were measured between the 1st test session and the 2nd test session during all tasks; while performance was found to improve during the 2nd test session for the motor and sensory tasks, it declined during the cognitive task. The findings of this research indicate that there was a regulatory mechanism for fatigue that altered the manner in which performance, psychophysical and subjective variables were modified over time, initiating a unique fatigue regulation pattern for each variable and each task. This regulation mechanism is understood to be a proactive and protective mechanism that functions through reducing a person’s ability to be vigilant, attentive, to exercise discernment, and to direct their level of responsiveness, essentially impacting how the body adapts to and copes with fatigue. The noted overall findings have industry implications; industries should consider accounting for the effects of this regulatory mechanism in their fatigue management interventions, specifically when designing job rotation and work/rest schedules because each cognitive task, having elicited a unique fatigue regulation pattern, ought to also have a different management program. , Microsoft� Office Word 2007 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2013
An analysis of temporal relations in languages: a comparative study of Mandarin and isiXhosa
- Authors: Ma, Xiujie
- Date: 2013 , 2013-01-30
- Subjects: Chinese language Xhosa language Grammar, Comparative and general -- Temporal constructions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2367 , http://hdl.handle.net/10962/d1003055
- Description: This study sought to investigate how temporal relations are expressed in Mandarin and isiXhosa. The objective was to compare how two typologically distinct languages, one isolating and the other agglutinating, cope with the encoding of situations that occur at different positions on the time line. Data was drawn from questionnaire responses from, and interviews with, isiXhosa speakers who provided translations of a wide range of sentences from English into isiXhosa. The study revealed that isiXhosa relies on the grammatical category – tense – to encode temporal relations, while Mandarin relies more on lexical and pragmatic devices – the use of temporal adverbials and the implication of aspectual markings – to locate a situation on the time line. Typically, each sentence in isiXhosa must be marked for tense: temporal adverbials are optional elements and used to more precisely locate the situation on the time line. By contrast, in Mandarin, temporal adverbials have a more central function in that they independently express different positions on the time line: without temporal adverbials, it is extremely difficult to locate a situation on the time line in some sentences. Another important difference between the two languages was revealed in this study: isiXhosa grammar allows speakers to talk about situations in terms of their distance (past or future) from the speech time whereas Mandarin grammar allows its speakers to talk about situations in terms of the internal properties (e.g. completed, ongoing, etc.) of those situations. The study revealed that isiXhosa and Mandarin are similar in one important respect: both languages have no formal properties, i.e. overt tense markers (isiXhosa) and compulsory temporal adverbials or other temporal devices (Mandarin) for marking the temporal location of present situations. The study also revealed that both languages encode ‘pastness’ in terms of whether or not the effects of the situation in question still remain at speech time.
- Full Text:
- Date Issued: 2013
- Authors: Ma, Xiujie
- Date: 2013 , 2013-01-30
- Subjects: Chinese language Xhosa language Grammar, Comparative and general -- Temporal constructions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2367 , http://hdl.handle.net/10962/d1003055
- Description: This study sought to investigate how temporal relations are expressed in Mandarin and isiXhosa. The objective was to compare how two typologically distinct languages, one isolating and the other agglutinating, cope with the encoding of situations that occur at different positions on the time line. Data was drawn from questionnaire responses from, and interviews with, isiXhosa speakers who provided translations of a wide range of sentences from English into isiXhosa. The study revealed that isiXhosa relies on the grammatical category – tense – to encode temporal relations, while Mandarin relies more on lexical and pragmatic devices – the use of temporal adverbials and the implication of aspectual markings – to locate a situation on the time line. Typically, each sentence in isiXhosa must be marked for tense: temporal adverbials are optional elements and used to more precisely locate the situation on the time line. By contrast, in Mandarin, temporal adverbials have a more central function in that they independently express different positions on the time line: without temporal adverbials, it is extremely difficult to locate a situation on the time line in some sentences. Another important difference between the two languages was revealed in this study: isiXhosa grammar allows speakers to talk about situations in terms of their distance (past or future) from the speech time whereas Mandarin grammar allows its speakers to talk about situations in terms of the internal properties (e.g. completed, ongoing, etc.) of those situations. The study revealed that isiXhosa and Mandarin are similar in one important respect: both languages have no formal properties, i.e. overt tense markers (isiXhosa) and compulsory temporal adverbials or other temporal devices (Mandarin) for marking the temporal location of present situations. The study also revealed that both languages encode ‘pastness’ in terms of whether or not the effects of the situation in question still remain at speech time.
- Full Text:
- Date Issued: 2013
An analysis of the distribution and use of teaching aids in mathematics in selected Windhoek secondary schools
- Authors: Dzambara, Tobias Munyaradzi
- Date: 2013
- Subjects: Mathematics -- Study and teaching (Secondary) -- Namibia Teaching -- Aids and devices -- Research
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: vital:1344 , http://hdl.handle.net/10962/d1001410
- Description: This study investigates the types of mathematics teaching aids available at both public and private secondary schools in Windhoek. The study characterises their usage and source as well as teachers’ perceptions towards the use of such teaching resources in the Mathematics classroom. The study is grounded in an interpretive paradigm and employed a mixed methods approach to generate both quantitative and qualitative data in two sequential phases. Phase 1 of the research process, which involved 75 Mathematics teachers, took the form of an audit of the availability and use of teaching aids at 25 secondary schools in Windhoek. A case study methodology was adopted in Phase 2 which focused on five purposively selected schools that displayed different characteristics in terms of the availability of teaching resources. The study found that the majority of teachers at secondary schools in Windhoek have a positive attitude towards the importance and role of teaching aids in Mathematics, seeing them as promoters of hands-on engagement, visual reasoning, active participation and motivation amongst learners. However, in some instances schools are underresourced with respect to certain types of teaching aids, specifically graph boards, geoboards, geometric models and computers. A need for appropriate in-school support on the use of teaching aids was also identified
- Full Text:
- Date Issued: 2013
- Authors: Dzambara, Tobias Munyaradzi
- Date: 2013
- Subjects: Mathematics -- Study and teaching (Secondary) -- Namibia Teaching -- Aids and devices -- Research
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: vital:1344 , http://hdl.handle.net/10962/d1001410
- Description: This study investigates the types of mathematics teaching aids available at both public and private secondary schools in Windhoek. The study characterises their usage and source as well as teachers’ perceptions towards the use of such teaching resources in the Mathematics classroom. The study is grounded in an interpretive paradigm and employed a mixed methods approach to generate both quantitative and qualitative data in two sequential phases. Phase 1 of the research process, which involved 75 Mathematics teachers, took the form of an audit of the availability and use of teaching aids at 25 secondary schools in Windhoek. A case study methodology was adopted in Phase 2 which focused on five purposively selected schools that displayed different characteristics in terms of the availability of teaching resources. The study found that the majority of teachers at secondary schools in Windhoek have a positive attitude towards the importance and role of teaching aids in Mathematics, seeing them as promoters of hands-on engagement, visual reasoning, active participation and motivation amongst learners. However, in some instances schools are underresourced with respect to certain types of teaching aids, specifically graph boards, geoboards, geometric models and computers. A need for appropriate in-school support on the use of teaching aids was also identified
- Full Text:
- Date Issued: 2013
An assessment of change readiness prior to significant organisational change
- Authors: Bedser, Mark Bernard
- Date: 2013
- Subjects: Organization change -- South Africa -- Case studies Eskom (Firm) -- Management , ADKAR model
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:716 , http://hdl.handle.net/10962/d1001870
- Description: This research paper is broken up into three sections, namely an evaluation report, a literature review and research methodology. The evaluation report section is the assessment of the current state of change readiness within the Eskom Contact Centre’s based upon what the literature on change readiness prescribes. The timing of the change readiness assessment is just prior to significant organisational change. The organisational change that was about to be initiated by the organisation was initiated from the boardroom of the most senior echelons of the organisation, and was directed in a top down approach, being a strategic organisational change. The change is deemed to be critical to the organisation being able to meet its long term strategic and sustainability objectives. A critical examination of the literature explored the meaning of change readiness, the importance of it and explained the consequences for organisations that commit to transformational agendas without being ready. Key concepts such as such resistance to change and organisational inertia are described and differentiated from change readiness. The ADKAR change model and its change readiness assessment instrument were used due to the organisations preference for the model. The ADKAR model formed the framework for the analyses of the data, the discussion of the results and the recommendations to the organisation. The research conducted was quantitative in nature; a questionnaire was distributed to the employees of the seven Eskom Contact centre sites around the country through an email. A slightly modified version of the ADKAR change readiness questionnaire was sent via email with an on-line questionnaire link on it; and questions on individual readiness for change were used to assess the level of readiness of the employees. Most of the descriptive and inferential statistics were analysed with the use of Excel (version, 2010), with Factor Analysis being done in research showed that: - The factors as proposed by the ADKAR change readiness assessment questionnaire (i.e. Awareness, Desire, Knowledge, Ability and Reinforcement) are not different enough to be considered as independent factors for this data set. Based on factor analysis, the factors were subsequently amended from five to three, namely Readiness, Opportunity Realisation and Uncertainty. - The Contact Centre employees were somewhat ready for change. - The Contact Centres needed to focus on all amended ADKAR factors in order to improve the readiness of the department. - The readiness levels in response to the roll out were more or less uniform. The study shows that given Eskom’s preference for the ADKAR model, future research within Eskom should therefore be conducted more circumspectly with respect to ascertaining the validity of the ADKAR factors. The study also makes mention that future work and/or research will need to be conducted, specifically on the readiness of the organisation itself, in order to improve the probability of transformational success. The ADKAR assessment is a people focused assessment and therefore focuses only on the readiness of the individual. Factors such as the adequacy of the current state of resources within the organisation, which incorporate aspects such as infrastructure, technology and staffing, will also need to be assessed to make a more holistic statement of change readiness. A concise review of the literature is incorporated into the Evaluation Report of Section 1 to underpin the study. In Section 2 a more extensive review of the literature is presented. Similarly, the design of the research is discussed in more detail in Section 3 to both describe and justify the appropriateness of the research methodology, and to give a detailed account of the way in which the research was carried out.
- Full Text:
- Date Issued: 2013
- Authors: Bedser, Mark Bernard
- Date: 2013
- Subjects: Organization change -- South Africa -- Case studies Eskom (Firm) -- Management , ADKAR model
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:716 , http://hdl.handle.net/10962/d1001870
- Description: This research paper is broken up into three sections, namely an evaluation report, a literature review and research methodology. The evaluation report section is the assessment of the current state of change readiness within the Eskom Contact Centre’s based upon what the literature on change readiness prescribes. The timing of the change readiness assessment is just prior to significant organisational change. The organisational change that was about to be initiated by the organisation was initiated from the boardroom of the most senior echelons of the organisation, and was directed in a top down approach, being a strategic organisational change. The change is deemed to be critical to the organisation being able to meet its long term strategic and sustainability objectives. A critical examination of the literature explored the meaning of change readiness, the importance of it and explained the consequences for organisations that commit to transformational agendas without being ready. Key concepts such as such resistance to change and organisational inertia are described and differentiated from change readiness. The ADKAR change model and its change readiness assessment instrument were used due to the organisations preference for the model. The ADKAR model formed the framework for the analyses of the data, the discussion of the results and the recommendations to the organisation. The research conducted was quantitative in nature; a questionnaire was distributed to the employees of the seven Eskom Contact centre sites around the country through an email. A slightly modified version of the ADKAR change readiness questionnaire was sent via email with an on-line questionnaire link on it; and questions on individual readiness for change were used to assess the level of readiness of the employees. Most of the descriptive and inferential statistics were analysed with the use of Excel (version, 2010), with Factor Analysis being done in research showed that: - The factors as proposed by the ADKAR change readiness assessment questionnaire (i.e. Awareness, Desire, Knowledge, Ability and Reinforcement) are not different enough to be considered as independent factors for this data set. Based on factor analysis, the factors were subsequently amended from five to three, namely Readiness, Opportunity Realisation and Uncertainty. - The Contact Centre employees were somewhat ready for change. - The Contact Centres needed to focus on all amended ADKAR factors in order to improve the readiness of the department. - The readiness levels in response to the roll out were more or less uniform. The study shows that given Eskom’s preference for the ADKAR model, future research within Eskom should therefore be conducted more circumspectly with respect to ascertaining the validity of the ADKAR factors. The study also makes mention that future work and/or research will need to be conducted, specifically on the readiness of the organisation itself, in order to improve the probability of transformational success. The ADKAR assessment is a people focused assessment and therefore focuses only on the readiness of the individual. Factors such as the adequacy of the current state of resources within the organisation, which incorporate aspects such as infrastructure, technology and staffing, will also need to be assessed to make a more holistic statement of change readiness. A concise review of the literature is incorporated into the Evaluation Report of Section 1 to underpin the study. In Section 2 a more extensive review of the literature is presented. Similarly, the design of the research is discussed in more detail in Section 3 to both describe and justify the appropriateness of the research methodology, and to give a detailed account of the way in which the research was carried out.
- Full Text:
- Date Issued: 2013
An assessment of the Kenyan coastal artisanal fishery and implications for the introduction of fish aggregation devices
- Authors: Mbaru, Emmanuel Kakunde
- Date: 2013 , 2013-07-30
- Subjects: Fisheries -- Kenya , Fishery management -- Kenya , Fish aggregation devices , Small-scale fisheries -- Kenya , Small-scale fisheries -- Economic aspects -- Kenya
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5341 , http://hdl.handle.net/10962/d1006055 , Fisheries -- Kenya , Fishery management -- Kenya , Fish aggregation devices , Small-scale fisheries -- Kenya , Small-scale fisheries -- Economic aspects -- Kenya
- Description: The marine fishery in Kenya is predominantly small-scale and artisanal with about 11,000 fishers intensely fishing near shore coastal reefs using minimally selective fishing gears. A large majority (88%) of fishers use outdated equipment such as basket traps, beach seines, hand lines (hook and lines), fence traps, gillnets, spearguns and cast nets. Handmade canoes propelled by paddles (kasia) or sail power are used to access offshore waters, while only a few fishers have motorized boats. Although fishers along this coast know and express the potential of offshore fishing, most of them are disempowered and unable to access any of the largely untapped offshore pelagic resources. Using a unique dataset from four distinct coastal areas: Funzi-Shirazi bay area, Diani-Chale area, Mombasa-Kilifi north coast area and the Malindi-Ungwana bay area, containing species level length frequency catch data from the multi-gear and multi-species fishery, abundance of specific species, gear use comparisons in various regions, catch per unit effort and total catch estimate over a nine year period (2001 – 2009) were evaluated. Despite high diversity in the fishery, five species (Lethrinus lentjan, Siganus sutor, Leptoscarus vaigiensis, Lethrinus harak and Parupeneus macronemus) represented over 75% of the catch. A total of 11 legitimate gears were observed in this coastal artisanal fishery with basket traps (42%) being the most popular. Fishers along the Mombasa-Kilifi area predominatly used beach seines while those in Diani-Chale, Malindi-Ungwana bay and Funzi-shirazi bay predominaltly used spearguns, gillnets and basket traps, respectively. Apart from gillnets, a general declining trend for most of the gear types was observed since 2004. Beach seines recorded the lowest (20.9±0.2 cm) mean length while gillnets recorded the highest (34.2±0.3 cm). The highest catch (~26,000 metric tons) came in 2001 and the lowest (~15,000 metric tons) in 2005. The highest number of fishers was observed in 2008 while 2009 recorded the highest (4.8±2.3) mean number of hours per outing. The mean annual CPUE per region ranged from (1.5 kg.fisher-1.hr-1) in Diani-Chale to (1.0 kg.fisher-1.hr-1) in Malindi-Ungwana bay. Making use of questionnaire data, the attitudes towards offshore fishing strategies, FADs in particular, were evaluated. Some communities (about 25% in every location) were not even aware of FAD fisheries. With the imminent introduction of a FAD fishery in Kenya, it was concluded that, for this fishery to realize its full potential, training on FAD fishing techniques has to be done. Finally, effective management is necessary if small-scale fisheries are to continue providing food security for many poor coastal communities. Gear-based management in Kenya, although under represented and under studied, has the potential to be adaptive, address multiple objectives, and be crafted to the socio-economic setting. Management effectiveness in near shore fisheries has generally been evaluated at the scale of the fish community. However, community level indicators can mask species-specific declines that provide significant portions of the fisheries yields and income. This thesis seeks to identify ways in which the Kenyan artisanal fishery can be sustained and managed from within coastal communities, giving them the resources and education to effectively improve their lives. The introduction of a offshore FAD fishery and hence access to offshore pelagic species provides an opportunity to not only alleviate pressure on coastal resources but also to empower coastal communities and contribute to the growth of Kenya’s national economy as a whole.
- Full Text:
- Date Issued: 2013
- Authors: Mbaru, Emmanuel Kakunde
- Date: 2013 , 2013-07-30
- Subjects: Fisheries -- Kenya , Fishery management -- Kenya , Fish aggregation devices , Small-scale fisheries -- Kenya , Small-scale fisheries -- Economic aspects -- Kenya
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5341 , http://hdl.handle.net/10962/d1006055 , Fisheries -- Kenya , Fishery management -- Kenya , Fish aggregation devices , Small-scale fisheries -- Kenya , Small-scale fisheries -- Economic aspects -- Kenya
- Description: The marine fishery in Kenya is predominantly small-scale and artisanal with about 11,000 fishers intensely fishing near shore coastal reefs using minimally selective fishing gears. A large majority (88%) of fishers use outdated equipment such as basket traps, beach seines, hand lines (hook and lines), fence traps, gillnets, spearguns and cast nets. Handmade canoes propelled by paddles (kasia) or sail power are used to access offshore waters, while only a few fishers have motorized boats. Although fishers along this coast know and express the potential of offshore fishing, most of them are disempowered and unable to access any of the largely untapped offshore pelagic resources. Using a unique dataset from four distinct coastal areas: Funzi-Shirazi bay area, Diani-Chale area, Mombasa-Kilifi north coast area and the Malindi-Ungwana bay area, containing species level length frequency catch data from the multi-gear and multi-species fishery, abundance of specific species, gear use comparisons in various regions, catch per unit effort and total catch estimate over a nine year period (2001 – 2009) were evaluated. Despite high diversity in the fishery, five species (Lethrinus lentjan, Siganus sutor, Leptoscarus vaigiensis, Lethrinus harak and Parupeneus macronemus) represented over 75% of the catch. A total of 11 legitimate gears were observed in this coastal artisanal fishery with basket traps (42%) being the most popular. Fishers along the Mombasa-Kilifi area predominatly used beach seines while those in Diani-Chale, Malindi-Ungwana bay and Funzi-shirazi bay predominaltly used spearguns, gillnets and basket traps, respectively. Apart from gillnets, a general declining trend for most of the gear types was observed since 2004. Beach seines recorded the lowest (20.9±0.2 cm) mean length while gillnets recorded the highest (34.2±0.3 cm). The highest catch (~26,000 metric tons) came in 2001 and the lowest (~15,000 metric tons) in 2005. The highest number of fishers was observed in 2008 while 2009 recorded the highest (4.8±2.3) mean number of hours per outing. The mean annual CPUE per region ranged from (1.5 kg.fisher-1.hr-1) in Diani-Chale to (1.0 kg.fisher-1.hr-1) in Malindi-Ungwana bay. Making use of questionnaire data, the attitudes towards offshore fishing strategies, FADs in particular, were evaluated. Some communities (about 25% in every location) were not even aware of FAD fisheries. With the imminent introduction of a FAD fishery in Kenya, it was concluded that, for this fishery to realize its full potential, training on FAD fishing techniques has to be done. Finally, effective management is necessary if small-scale fisheries are to continue providing food security for many poor coastal communities. Gear-based management in Kenya, although under represented and under studied, has the potential to be adaptive, address multiple objectives, and be crafted to the socio-economic setting. Management effectiveness in near shore fisheries has generally been evaluated at the scale of the fish community. However, community level indicators can mask species-specific declines that provide significant portions of the fisheries yields and income. This thesis seeks to identify ways in which the Kenyan artisanal fishery can be sustained and managed from within coastal communities, giving them the resources and education to effectively improve their lives. The introduction of a offshore FAD fishery and hence access to offshore pelagic species provides an opportunity to not only alleviate pressure on coastal resources but also to empower coastal communities and contribute to the growth of Kenya’s national economy as a whole.
- Full Text:
- Date Issued: 2013
An assessment of urban residents' knowledge and appreciation of the intangible benefits of trees in two medium sized towns in South Africa
- Authors: Chinyimba, Abby
- Date: 2013
- Subjects: Trees in cities -- South Africa--Limpopo , Cities and towns -- South Africa -- Limpopo , Ecology -- South Africa -- Limpopo , Human-plant relationships -- South Africa -- Limpopo , Plants and civilization -- South Africa -- Limpopo , Willingness to pay -- South Africa -- Limpopo , Limpopo (South Africa) -- Environmental conditions , Cultural importance , Cultural and regulating services , Intangible benefits , Urban systems
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4730 , http://hdl.handle.net/10962/d1001957
- Description: In order to meet the different public needs and requirements of contemporary urban society, a better understanding of public perceptions, appreciation and knowledge of the assorted values derived from urban trees is beneficial for improved urban greening. Thus, this study carried out an assessment of urban residents’ knowledge and appreciation of the benefits of trees and the role they play in enhancing the quality of life in urban systems. The study primarily focused on the intangible benefits (also referred to as cultural and regulating services) of urban trees, because most research to date in South Africa on trees and the benefits derived from them is biased towards the provisioning services of trees in rural areas. The significance and contribution of the intangible benefits of trees in urban systems is often underestimated and not seriously taken into account by urban planners, policy makers and other key decision makers. The study was conducted in three different residential settlement types (formal townships, RDP settlements and informal settlements) in two towns in the Limpopo Province in South Africa, namely Bela-Bela and Tzaneen. Findings revealed that the intangible benefits of trees are seen to play a significant role in improving both residents’ quality of life and the environmental conditions in cities, including the preservation of biodiversity. Findings also showed that urban residents had strong spiritual connections with trees and placed considerable cultural and historical importance on specific tree species and individual trees. Urban residents in both towns had moderate knowledge of the intangible benefits of trees based on the knowledge score that was created for the purposes of this study. Fifty seven percent of the residents had ‘reasonable’ knowledge of some of the intangible benefits of trees, while 43% had low levels of knowledge. That said, the majority of residents demonstrated high appreciation (98%) of the intangible benefits of trees (especially social and cultural values), with few residents not recognising these, suggesting that knowledge does not necessarily lead to appreciation. Age and level of education were found to influence knowledge of the intangible benefits of trees. A large proportion (86%) of residents who possessed tertiary level qualifications had more knowledge of the intangible benefits of trees as compared to residents with no formal education. Findings also revealed that younger respondents (60%) had more knowledge of the intangible benefits of trees. Factors that influenced appreciation of the intangible benefits of trees included links to crime, peoples’ value systems (their pro-environmental and altruistic values) and residential settlement type. Sixty five percent of residents in both towns felt that urban street trees and trees in public spaces attract criminals and promote crime, while 67% of RDP and 96% of informal township residents did not use or appreciate the social and recreational benefits of trees mainly because of the absence or long distances to public parks. A Willingness To Pay (WTP) survey revealed that a high proportion of residents in Bela-Bela (86%) were WTP a small annual fee in order to sustain greening initiatives in their communities compared to the residents in Tzaneen (53%). In terms of the planting and retention of trees, it was found that 300 households in both study towns had planted and retained a total of 1 615 trees in spite of the various factors that negatively influenced planting and retention of trees such as residency time and tenure security. The majority (66%) of informal township residents said tenure security was an important factor to consider when making tree planting decisions, while this was not an issue for formal township and RDP residents. Policy implications and recommendations are presented to help municipalities and urban planners improve and develop effective policies and programmes that will enable implementation of sustainable urban greening programmes
- Full Text:
- Date Issued: 2013
- Authors: Chinyimba, Abby
- Date: 2013
- Subjects: Trees in cities -- South Africa--Limpopo , Cities and towns -- South Africa -- Limpopo , Ecology -- South Africa -- Limpopo , Human-plant relationships -- South Africa -- Limpopo , Plants and civilization -- South Africa -- Limpopo , Willingness to pay -- South Africa -- Limpopo , Limpopo (South Africa) -- Environmental conditions , Cultural importance , Cultural and regulating services , Intangible benefits , Urban systems
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4730 , http://hdl.handle.net/10962/d1001957
- Description: In order to meet the different public needs and requirements of contemporary urban society, a better understanding of public perceptions, appreciation and knowledge of the assorted values derived from urban trees is beneficial for improved urban greening. Thus, this study carried out an assessment of urban residents’ knowledge and appreciation of the benefits of trees and the role they play in enhancing the quality of life in urban systems. The study primarily focused on the intangible benefits (also referred to as cultural and regulating services) of urban trees, because most research to date in South Africa on trees and the benefits derived from them is biased towards the provisioning services of trees in rural areas. The significance and contribution of the intangible benefits of trees in urban systems is often underestimated and not seriously taken into account by urban planners, policy makers and other key decision makers. The study was conducted in three different residential settlement types (formal townships, RDP settlements and informal settlements) in two towns in the Limpopo Province in South Africa, namely Bela-Bela and Tzaneen. Findings revealed that the intangible benefits of trees are seen to play a significant role in improving both residents’ quality of life and the environmental conditions in cities, including the preservation of biodiversity. Findings also showed that urban residents had strong spiritual connections with trees and placed considerable cultural and historical importance on specific tree species and individual trees. Urban residents in both towns had moderate knowledge of the intangible benefits of trees based on the knowledge score that was created for the purposes of this study. Fifty seven percent of the residents had ‘reasonable’ knowledge of some of the intangible benefits of trees, while 43% had low levels of knowledge. That said, the majority of residents demonstrated high appreciation (98%) of the intangible benefits of trees (especially social and cultural values), with few residents not recognising these, suggesting that knowledge does not necessarily lead to appreciation. Age and level of education were found to influence knowledge of the intangible benefits of trees. A large proportion (86%) of residents who possessed tertiary level qualifications had more knowledge of the intangible benefits of trees as compared to residents with no formal education. Findings also revealed that younger respondents (60%) had more knowledge of the intangible benefits of trees. Factors that influenced appreciation of the intangible benefits of trees included links to crime, peoples’ value systems (their pro-environmental and altruistic values) and residential settlement type. Sixty five percent of residents in both towns felt that urban street trees and trees in public spaces attract criminals and promote crime, while 67% of RDP and 96% of informal township residents did not use or appreciate the social and recreational benefits of trees mainly because of the absence or long distances to public parks. A Willingness To Pay (WTP) survey revealed that a high proportion of residents in Bela-Bela (86%) were WTP a small annual fee in order to sustain greening initiatives in their communities compared to the residents in Tzaneen (53%). In terms of the planting and retention of trees, it was found that 300 households in both study towns had planted and retained a total of 1 615 trees in spite of the various factors that negatively influenced planting and retention of trees such as residency time and tenure security. The majority (66%) of informal township residents said tenure security was an important factor to consider when making tree planting decisions, while this was not an issue for formal township and RDP residents. Policy implications and recommendations are presented to help municipalities and urban planners improve and develop effective policies and programmes that will enable implementation of sustainable urban greening programmes
- Full Text:
- Date Issued: 2013
An empirical analysis of financial stress within South Africa and its apparent co-movement with financial stress emanating from advanced and emerging economies
- Authors: Graham, Brydone
- Date: 2013
- Subjects: Financial crises -- South Africa Financial crises -- Developing countries Globalization -- Economic aspects -- South Africa International economic relations South Africa -- Economic conditions
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1053 , http://hdl.handle.net/10962/d1006795
- Description: The identification of financial stress, and an understanding of financial contagion on a global scale, is of critical importance to a South African economy that is becoming increasingly integrated into the global economy. The last decade has been characterised by periods of high economic growth, but also periods of significant financial instability culminating in global economic crises. This study examines the extent to which the South African financial system is exposed to distress abroad by identifying and measuring the co-movement of financial stress originating from within and outside South Africa. The study can be separated into two sections: the identification of financial stress and the measurement of financial contagion. Using monthly data for the period 2000 to 2012, three indices were constructed for the emerging markets, advanced economies and South Africa using varianceequal weighting. The indices were tested for contagion using the Johansen and Jesulius (1990) multivariate cointegration approach supplemented with basic OLS architecture and Impulse Response analysis. The results indicate the three constructed indices were highly accurate at identifying the intensity and timing of financial stress over the three regions respectively. It was found that the South African financial sector is highly susceptible to financial stress originating from advanced economies. The results obtained for financial stress emanating from emerging markets were not as conclusive and found to be insignificant. Overall, it is clear that the methods employed to identify financial stress are highly accurate and that South Africa is highly susceptible to financial stress originating from abroad. It is clear that advanced economies have a greater ability to affect financial stress in South Africa via contagion. It must be noted that this does not conclude that South Africa is not affected by emerging market crises, but that these crises tend to affect South Africa through advanced economy channels as defined within this thesis.
- Full Text:
- Date Issued: 2013
- Authors: Graham, Brydone
- Date: 2013
- Subjects: Financial crises -- South Africa Financial crises -- Developing countries Globalization -- Economic aspects -- South Africa International economic relations South Africa -- Economic conditions
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1053 , http://hdl.handle.net/10962/d1006795
- Description: The identification of financial stress, and an understanding of financial contagion on a global scale, is of critical importance to a South African economy that is becoming increasingly integrated into the global economy. The last decade has been characterised by periods of high economic growth, but also periods of significant financial instability culminating in global economic crises. This study examines the extent to which the South African financial system is exposed to distress abroad by identifying and measuring the co-movement of financial stress originating from within and outside South Africa. The study can be separated into two sections: the identification of financial stress and the measurement of financial contagion. Using monthly data for the period 2000 to 2012, three indices were constructed for the emerging markets, advanced economies and South Africa using varianceequal weighting. The indices were tested for contagion using the Johansen and Jesulius (1990) multivariate cointegration approach supplemented with basic OLS architecture and Impulse Response analysis. The results indicate the three constructed indices were highly accurate at identifying the intensity and timing of financial stress over the three regions respectively. It was found that the South African financial sector is highly susceptible to financial stress originating from advanced economies. The results obtained for financial stress emanating from emerging markets were not as conclusive and found to be insignificant. Overall, it is clear that the methods employed to identify financial stress are highly accurate and that South Africa is highly susceptible to financial stress originating from abroad. It is clear that advanced economies have a greater ability to affect financial stress in South Africa via contagion. It must be noted that this does not conclude that South Africa is not affected by emerging market crises, but that these crises tend to affect South Africa through advanced economy channels as defined within this thesis.
- Full Text:
- Date Issued: 2013
An empirical investigation into task aversion
- Authors: Sunshine, Megan
- Date: 2013 , 2013-07-25
- Subjects: Work aversion , Mental fatigue , Labor productivity , Employees -- Workload , Industrial hygiene
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5138 , http://hdl.handle.net/10962/d1006085 , Work aversion , Mental fatigue , Labor productivity , Employees -- Workload , Industrial hygiene
- Description: Aversion is a complex phenomenon that arises over time through performance of cognitively demanding tasks and has been associated with the mechanisms of mental fatigue and compensatory control. However, little is known about this sensation to dissociate from the task at hand and the causation thereof. It is apparent that aversion is a negative state for the operator and could result in decreased performance and productivity. Through identification of factors that contribute to aversion when performing cognitively demanding tasks, recommendations to reduce design deficits may be employed to promote worker wellbeing and further advance performance and productivity. The current study examined possible factors that may influence aversion experienced through execution of cognitive tasks. A subsequent aim of this study was to assess a possible cause of aversion. The cause of aversion was hypothesized to be related to efficiency, namely the perception of efficiency when performing tasks and actual efficiency calculated through performance of tasks in relation to the expenditure of effort. Four investigations were undertaken with a non-repeated design between investigations and a repeated design within investigations. The first investigation was an analysis of the effect that stimulus cycling had on the aversion experienced. This consisted of a proof reading task with two conditions varying in the repetitiveness of the text, therefore, allowing an analysis as to how aversion is altered by the provision of a new stimulus to the participants. Investigation two investigated the effect that task difficulty imposed on aversion experienced. This comprised of two conditions with varied difficulty that were implemented through a driving simulator tracking task with difficulty altered by the width of the driving lane. The effect of performance feedback on the aversion experienced towards a task was the focus of the third investigation. The effect on aversion experienced was assessed through a driving simulator tracking task with a condition providing feedback of performance to participants and a condition with no knowledge of performance. The final experiment evaluated the effect of task alternations on aversion. This experiment was conducted through alternations between a driving simulator tracking task and a choice reaction task. The choice reaction tasks required participants to identify critical and non-critical stimulus. Four conditions were required for this experiment and were made up of two conditions where there was provision of alternation that varied in frequencies between the two tasks (medium alternation condition and fast alternation condition) and two conditions where no alternations were instated (driving simulator task condition and choice reaction task condition). Separations between all testing conditions were three or more days apart with sixty participants distributed between the investigations. Test duration of each condition was 30 minutes. Subjective data was recorded throughout investigations for all conditions in the form of aversion, subjectively perceived efficiency and rate of perceived exertion. Objective data was collected in the form of physiological responses and performance of tasks for the analysis of objective efficiency. For factors influencing aversion analysis, no differences in aversion experienced were found for the task difficulty and performance feedback investigations. Aversion was found to be less for the changes imposed through the task cycles and task alternation investigations. This concludes that aversion is aggravated through monotonous tasks and by a change of the stimulus or the structure of the cognitive tasks provided to operators; aversion can be alleviated. The results for the cause of aversion analysis found no difference in objective efficiency over time, with a subsequent decrease in perceived efficiency associated with the increasing aversion. Inference from these findings suggest that aversion cannot be attributed to objective inefficiency of task performance, however it can further be assumed that perception of actual efficiency is inaccurate. Perception of efficiency however had a large influence on the sensation of aversion. Aversion is seen to be more of a product of time on task, however whether this is mechanism of fatigue or compensatory control is still to be determined.
- Full Text:
- Date Issued: 2013
- Authors: Sunshine, Megan
- Date: 2013 , 2013-07-25
- Subjects: Work aversion , Mental fatigue , Labor productivity , Employees -- Workload , Industrial hygiene
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5138 , http://hdl.handle.net/10962/d1006085 , Work aversion , Mental fatigue , Labor productivity , Employees -- Workload , Industrial hygiene
- Description: Aversion is a complex phenomenon that arises over time through performance of cognitively demanding tasks and has been associated with the mechanisms of mental fatigue and compensatory control. However, little is known about this sensation to dissociate from the task at hand and the causation thereof. It is apparent that aversion is a negative state for the operator and could result in decreased performance and productivity. Through identification of factors that contribute to aversion when performing cognitively demanding tasks, recommendations to reduce design deficits may be employed to promote worker wellbeing and further advance performance and productivity. The current study examined possible factors that may influence aversion experienced through execution of cognitive tasks. A subsequent aim of this study was to assess a possible cause of aversion. The cause of aversion was hypothesized to be related to efficiency, namely the perception of efficiency when performing tasks and actual efficiency calculated through performance of tasks in relation to the expenditure of effort. Four investigations were undertaken with a non-repeated design between investigations and a repeated design within investigations. The first investigation was an analysis of the effect that stimulus cycling had on the aversion experienced. This consisted of a proof reading task with two conditions varying in the repetitiveness of the text, therefore, allowing an analysis as to how aversion is altered by the provision of a new stimulus to the participants. Investigation two investigated the effect that task difficulty imposed on aversion experienced. This comprised of two conditions with varied difficulty that were implemented through a driving simulator tracking task with difficulty altered by the width of the driving lane. The effect of performance feedback on the aversion experienced towards a task was the focus of the third investigation. The effect on aversion experienced was assessed through a driving simulator tracking task with a condition providing feedback of performance to participants and a condition with no knowledge of performance. The final experiment evaluated the effect of task alternations on aversion. This experiment was conducted through alternations between a driving simulator tracking task and a choice reaction task. The choice reaction tasks required participants to identify critical and non-critical stimulus. Four conditions were required for this experiment and were made up of two conditions where there was provision of alternation that varied in frequencies between the two tasks (medium alternation condition and fast alternation condition) and two conditions where no alternations were instated (driving simulator task condition and choice reaction task condition). Separations between all testing conditions were three or more days apart with sixty participants distributed between the investigations. Test duration of each condition was 30 minutes. Subjective data was recorded throughout investigations for all conditions in the form of aversion, subjectively perceived efficiency and rate of perceived exertion. Objective data was collected in the form of physiological responses and performance of tasks for the analysis of objective efficiency. For factors influencing aversion analysis, no differences in aversion experienced were found for the task difficulty and performance feedback investigations. Aversion was found to be less for the changes imposed through the task cycles and task alternation investigations. This concludes that aversion is aggravated through monotonous tasks and by a change of the stimulus or the structure of the cognitive tasks provided to operators; aversion can be alleviated. The results for the cause of aversion analysis found no difference in objective efficiency over time, with a subsequent decrease in perceived efficiency associated with the increasing aversion. Inference from these findings suggest that aversion cannot be attributed to objective inefficiency of task performance, however it can further be assumed that perception of actual efficiency is inaccurate. Perception of efficiency however had a large influence on the sensation of aversion. Aversion is seen to be more of a product of time on task, however whether this is mechanism of fatigue or compensatory control is still to be determined.
- Full Text:
- Date Issued: 2013