Alkane oxidation using metallophthalocyanine as homogeneous catalysts
- Authors: Grootboom, Natasha Denise
- Date: 2002
- Subjects: Oxidation , Alkanes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4449 , http://hdl.handle.net/10962/d1007794
- Description: Iron polychlorophthalocyanine (FePc(Cl)₁₆) and tetrasulfophthalocyanine ([M¹¹TSPc]⁴) complexes of iron, cobalt and manganese are employed as catalysts for the oxidation of cyclohexane using tert-butyl hydroperoxide (TBHP), chloroperoxybenzoic acid (CPBA) and hydrogen peroxide as oxidants. Catalysis using the FePc(Cl)₁₆ was performed in a dimethylformamide:dichloromethane (3 :7) solvent mixture. For the [Fe¹¹TSPc]⁴⁻, [Co¹¹TSPc]⁻ and [Mn¹¹TSPc]⁴⁻catalysts, a water:methanol (1:9) mixture was employed. The products of the catalysis are cyclohexanone, cyclohexanol and cyclohexanediol. The relative percentage yields, percentage selectivity and overall percentage conversion of the products depended on types of oxidant, or catalyst, concentrations of substrate or catalysts and temperature. TBHP was found to be the best oxidant since minimal destruction of the catalyst and higher selectivity in the products were observed when this oxidant was employed. Of the four catalysts investigated [Fe¹¹TSPc]⁴⁻ yielded the highest overall percentage conversion of 20%.The mechanism of the oxidation of cyclohexane in the presence of the FePc(Cl)₁₆ and [M¹¹TSPc]⁴⁻ involves the oxidation of these catalysts, forming an Fe(IlI) phthalocyanine species as an intermediate. Electrocatalysis using [Co¹¹TSPc]⁴⁻ as catalyst, employed an aqueous pH 7 buffer medium for electro-oxidation of 4-pentenoic acid. An enone is suggested as the only oxidation product of 4-pentenoic acid. No degradation of [Co¹¹TSPc]⁴⁻ was observed during the electrocatalytic process. In this process water was used as a source of oxygen therefore eliminating the production of by products from oxidant as in the case of TBHP and CPBA. This system was studied In an attempt to set up conditions for alkane electrocatalytic oxidation.
- Full Text:
- Date Issued: 2002
- Authors: Grootboom, Natasha Denise
- Date: 2002
- Subjects: Oxidation , Alkanes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4449 , http://hdl.handle.net/10962/d1007794
- Description: Iron polychlorophthalocyanine (FePc(Cl)₁₆) and tetrasulfophthalocyanine ([M¹¹TSPc]⁴) complexes of iron, cobalt and manganese are employed as catalysts for the oxidation of cyclohexane using tert-butyl hydroperoxide (TBHP), chloroperoxybenzoic acid (CPBA) and hydrogen peroxide as oxidants. Catalysis using the FePc(Cl)₁₆ was performed in a dimethylformamide:dichloromethane (3 :7) solvent mixture. For the [Fe¹¹TSPc]⁴⁻, [Co¹¹TSPc]⁻ and [Mn¹¹TSPc]⁴⁻catalysts, a water:methanol (1:9) mixture was employed. The products of the catalysis are cyclohexanone, cyclohexanol and cyclohexanediol. The relative percentage yields, percentage selectivity and overall percentage conversion of the products depended on types of oxidant, or catalyst, concentrations of substrate or catalysts and temperature. TBHP was found to be the best oxidant since minimal destruction of the catalyst and higher selectivity in the products were observed when this oxidant was employed. Of the four catalysts investigated [Fe¹¹TSPc]⁴⁻ yielded the highest overall percentage conversion of 20%.The mechanism of the oxidation of cyclohexane in the presence of the FePc(Cl)₁₆ and [M¹¹TSPc]⁴⁻ involves the oxidation of these catalysts, forming an Fe(IlI) phthalocyanine species as an intermediate. Electrocatalysis using [Co¹¹TSPc]⁴⁻ as catalyst, employed an aqueous pH 7 buffer medium for electro-oxidation of 4-pentenoic acid. An enone is suggested as the only oxidation product of 4-pentenoic acid. No degradation of [Co¹¹TSPc]⁴⁻ was observed during the electrocatalytic process. In this process water was used as a source of oxygen therefore eliminating the production of by products from oxidant as in the case of TBHP and CPBA. This system was studied In an attempt to set up conditions for alkane electrocatalytic oxidation.
- Full Text:
- Date Issued: 2002
Investigating teaching strategies used by teachers to foster environmental learning in the Namibian Life Science curriculum
- Authors: Hoabes, Rosina
- Date: 2004
- Subjects: Life sciences -- Study and teaching -- Namibia Education -- Namibia Teaching -- Namibia Effective teaching -- Namibia Curriculum planning -- Namibia Educational change -- Namibia Environmental education -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1590 , http://hdl.handle.net/10962/d1003472
- Description: This study was carried out to investigate the strategies used by teachers to foster environmental learning in the Namibian Life Science curriculum in four schools in Swakopmund, Erongo Education Region. This study is a qualitative case study. I used semi-structured interviews, observation and document analysis as instruments to collect data. Two schools were selected to participate in the case study. Research participants included four teachers (two teachers from each school) of which two teachers are teaching at each school. The study was contextualised through a review of policy changes in Namibian education, which focus on learner-centred education. The study identified six strategies used by teachers to foster environmental learning in the Life Sciences curriculum. These are planning; working with information; practical, excursions and clubs; involving the learners; using visual aids and teaching materials; and choosing topics with a local focus. Through a consideration of the different strategies used by teachers, in relation to the learner-centred nature of the educational reform project in Namibia the study provides insight into the way in which teachers view learner-centred education. The study also illuminates how strategies used by teachers reflect learner-centred education principles and it outlines a number of tensions emerging in the fostering of environmental learning in learner-centred ways. The study identifies further support required by teachers, and makes recommendations which will further enhance the strategies used by teachers to foster the environmental learning focus in Life Sciences, and also enhance learner-centred teaching in Life Science.
- Full Text:
- Date Issued: 2004
- Authors: Hoabes, Rosina
- Date: 2004
- Subjects: Life sciences -- Study and teaching -- Namibia Education -- Namibia Teaching -- Namibia Effective teaching -- Namibia Curriculum planning -- Namibia Educational change -- Namibia Environmental education -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1590 , http://hdl.handle.net/10962/d1003472
- Description: This study was carried out to investigate the strategies used by teachers to foster environmental learning in the Namibian Life Science curriculum in four schools in Swakopmund, Erongo Education Region. This study is a qualitative case study. I used semi-structured interviews, observation and document analysis as instruments to collect data. Two schools were selected to participate in the case study. Research participants included four teachers (two teachers from each school) of which two teachers are teaching at each school. The study was contextualised through a review of policy changes in Namibian education, which focus on learner-centred education. The study identified six strategies used by teachers to foster environmental learning in the Life Sciences curriculum. These are planning; working with information; practical, excursions and clubs; involving the learners; using visual aids and teaching materials; and choosing topics with a local focus. Through a consideration of the different strategies used by teachers, in relation to the learner-centred nature of the educational reform project in Namibia the study provides insight into the way in which teachers view learner-centred education. The study also illuminates how strategies used by teachers reflect learner-centred education principles and it outlines a number of tensions emerging in the fostering of environmental learning in learner-centred ways. The study identifies further support required by teachers, and makes recommendations which will further enhance the strategies used by teachers to foster the environmental learning focus in Life Sciences, and also enhance learner-centred teaching in Life Science.
- Full Text:
- Date Issued: 2004
Labour migration, marriage and family life in a Ciskei village
- Authors: Manona, Cecil Wele
- Date: 1981
- Subjects: Migrant labor -- Social aspects -- South Africa -- Ciskei
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2107 , http://hdl.handle.net/10962/d1006884
- Description: From introduction: The aim of this thesis is to describe and analyse the effects of labour migration on marriage and family life. The field material is from Burnshill, a village situated in the Keiskammahoek district in the Ciskei. Keiskammahoek is bounded on the East by the districts of King William's Town and Stutterheim, on the West and South by Middledrift and on the North by Cathcart. The inhabitants of Burnshill are overwhelmingly Xhosa and Mfengu (the main ethnic groups in the Ciskei) but also include a small proportion of people whose clans are of Mpondo and Thembu origin. This village has undergone extensive change. As we shall show later, it was settled de novo by the Mfengu and the Xhosa during the second half of the past century. This is one of the reasons why it lacks the homogeneity and continuity of cultural tradition which are predominant features of long-established communities.
- Full Text:
- Date Issued: 1981
- Authors: Manona, Cecil Wele
- Date: 1981
- Subjects: Migrant labor -- Social aspects -- South Africa -- Ciskei
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2107 , http://hdl.handle.net/10962/d1006884
- Description: From introduction: The aim of this thesis is to describe and analyse the effects of labour migration on marriage and family life. The field material is from Burnshill, a village situated in the Keiskammahoek district in the Ciskei. Keiskammahoek is bounded on the East by the districts of King William's Town and Stutterheim, on the West and South by Middledrift and on the North by Cathcart. The inhabitants of Burnshill are overwhelmingly Xhosa and Mfengu (the main ethnic groups in the Ciskei) but also include a small proportion of people whose clans are of Mpondo and Thembu origin. This village has undergone extensive change. As we shall show later, it was settled de novo by the Mfengu and the Xhosa during the second half of the past century. This is one of the reasons why it lacks the homogeneity and continuity of cultural tradition which are predominant features of long-established communities.
- Full Text:
- Date Issued: 1981
The effect of different parameters on the rupture properties of leather in a tensile test
- Authors: Makhothe, Kelebohile
- Date: 1998
- Subjects: Leather -- Testing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5462 , http://hdl.handle.net/10962/d1005247 , Leather -- Testing
- Description: This thesis explores the effect of some parameters on the breaking strain, strength and the shape of the stress-strain curve of bovine leather as revealed by uniaxial tensile tests. The parameters explored are fatliquoring, moisture content, strain rate and cyclic stressing. A basic mechanical model of a simple two-dimensional weave is created and used to describe the effect of such a weave on the shape of the stress-strain curve. It is found that fatliquoring lubricates and opens up the fibre structure and thereby makes the weave more extensible. The increase in the extensibility depends on the direction in which samples are cut and therefore the manner in which the fibres are orientated. Patliquoring is observed to increase the degree to which fibres pull out at break. There are indications that the strength of fatliquored leather decreases with time of storage, while the extensibility increases. The effect of the strain rate on the breaking strain, the tensile strength and the shape of the stress-strain curve is not very clear. The stressing and releasing leather decreases the strength of leather when the fibres are orientated preferentially along the direction of the applied stresses, but has an insignificant effect in the transverse direction. It is concluded that the degree of lubrication in a weave and the orientation of the fibre bundles significantly influence the performance of leather in a test. Both moisture and fatliquoring lubricate the weave. In both the cases the degree of fibre adhesions in a weave is decreased. A well lubricated weave allows its constituent fibres to slide and align along the direction of the applied stresses, and this tends to occur before the fibres themselves areextended. Cyclic testing, at low strains, ruptures fibre adhesions and as a result induces permanent set and makes a hide softer. Most of the work done in breaking the fibre adhesion is done in the first cycle.
- Full Text:
- Date Issued: 1998
- Authors: Makhothe, Kelebohile
- Date: 1998
- Subjects: Leather -- Testing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5462 , http://hdl.handle.net/10962/d1005247 , Leather -- Testing
- Description: This thesis explores the effect of some parameters on the breaking strain, strength and the shape of the stress-strain curve of bovine leather as revealed by uniaxial tensile tests. The parameters explored are fatliquoring, moisture content, strain rate and cyclic stressing. A basic mechanical model of a simple two-dimensional weave is created and used to describe the effect of such a weave on the shape of the stress-strain curve. It is found that fatliquoring lubricates and opens up the fibre structure and thereby makes the weave more extensible. The increase in the extensibility depends on the direction in which samples are cut and therefore the manner in which the fibres are orientated. Patliquoring is observed to increase the degree to which fibres pull out at break. There are indications that the strength of fatliquored leather decreases with time of storage, while the extensibility increases. The effect of the strain rate on the breaking strain, the tensile strength and the shape of the stress-strain curve is not very clear. The stressing and releasing leather decreases the strength of leather when the fibres are orientated preferentially along the direction of the applied stresses, but has an insignificant effect in the transverse direction. It is concluded that the degree of lubrication in a weave and the orientation of the fibre bundles significantly influence the performance of leather in a test. Both moisture and fatliquoring lubricate the weave. In both the cases the degree of fibre adhesions in a weave is decreased. A well lubricated weave allows its constituent fibres to slide and align along the direction of the applied stresses, and this tends to occur before the fibres themselves areextended. Cyclic testing, at low strains, ruptures fibre adhesions and as a result induces permanent set and makes a hide softer. Most of the work done in breaking the fibre adhesion is done in the first cycle.
- Full Text:
- Date Issued: 1998
An investigation of how grade 10 learners make sense of concepts on refraction of light through exploring their cultural beliefs/everyday experiences about the rainbow : a case study
- Homateni, Rauha Kau Ndahalomwenyo
- Authors: Homateni, Rauha Kau Ndahalomwenyo
- Date: 2013
- Subjects: Science -- Study and teaching (Secondary) -- Namibia Light -- Study and teaching Light -- Study and teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1827 , http://hdl.handle.net/10962/d1003713
- Description: This study took place at a private high school in the Kavango region with my 32 grade 10B learners as the research participants. Its objective was to investigate how the grade 10 learners make sense of concepts on refraction of light through exploring their cultural beliefs/everyday experiences about the rainbow. This research study was essentially triggered by my own classroom experience of teaching the topic on refraction of light. In order to achieve the goal of this research, a qualitative case study located within an interpretive paradigm was adopted. To gather data I used multiple data gathering techniques such as brainstorming session, learners conducting interviews in the community, practical activities and focus group interviews. This resulted in descriptive data that qualified to be analyzed in a qualitative way. The themes that emerged from the generated data were coded using upper letter cases and various colours. A methodological triangulation was employed by using multiple data generation techniques. Member checking during focus group interviews also ensured validity in this case study. The findings of this study revealed that the use of learners’ cultural beliefs/everyday experiences can be used to enhance learner engagement, meaning making and conceptual development during the science lessons. In addition, the ways in which practical activities are designed and presented to learners in the science classroom determine learners’ participation and conceptual attainment. Therefore, based on my research findings, I recommend that teachers need to be trained to be able to elicit and integrate learners’ cultural beliefs/everyday experiences in conjunction with hands-on practical activities which focus on conceptual development during their science lessons. However, although this study had many benefits, it also showed that it is not easy to close the gap between learners’ prior everyday knowledge and school science. This warrants further research.
- Full Text:
- Date Issued: 2013
- Authors: Homateni, Rauha Kau Ndahalomwenyo
- Date: 2013
- Subjects: Science -- Study and teaching (Secondary) -- Namibia Light -- Study and teaching Light -- Study and teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1827 , http://hdl.handle.net/10962/d1003713
- Description: This study took place at a private high school in the Kavango region with my 32 grade 10B learners as the research participants. Its objective was to investigate how the grade 10 learners make sense of concepts on refraction of light through exploring their cultural beliefs/everyday experiences about the rainbow. This research study was essentially triggered by my own classroom experience of teaching the topic on refraction of light. In order to achieve the goal of this research, a qualitative case study located within an interpretive paradigm was adopted. To gather data I used multiple data gathering techniques such as brainstorming session, learners conducting interviews in the community, practical activities and focus group interviews. This resulted in descriptive data that qualified to be analyzed in a qualitative way. The themes that emerged from the generated data were coded using upper letter cases and various colours. A methodological triangulation was employed by using multiple data generation techniques. Member checking during focus group interviews also ensured validity in this case study. The findings of this study revealed that the use of learners’ cultural beliefs/everyday experiences can be used to enhance learner engagement, meaning making and conceptual development during the science lessons. In addition, the ways in which practical activities are designed and presented to learners in the science classroom determine learners’ participation and conceptual attainment. Therefore, based on my research findings, I recommend that teachers need to be trained to be able to elicit and integrate learners’ cultural beliefs/everyday experiences in conjunction with hands-on practical activities which focus on conceptual development during their science lessons. However, although this study had many benefits, it also showed that it is not easy to close the gap between learners’ prior everyday knowledge and school science. This warrants further research.
- Full Text:
- Date Issued: 2013
A study of growth and entrepreneurship of a small organisation in the automotive industry of South Africa
- Authors: White, Andrew Stephen
- Date: 2010
- Subjects: Entrepreneurship
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8608 , http://hdl.handle.net/10948/1525 , Entrepreneurship
- Description: The strategy of the organisation and its entrepreneur’s expectations of the organisation should be aligned in order to create an environment in which all entrepreneurs are motivated and work towards common goals. Furthermore, the entrepreneur’s life stages and personal life plans should be synchronised with the needs of the organisation to achieve the goals. As organisations pass through different stages of growth; they require different resources to assist in progression to next stages. As with organisations and their growth phases; entrepreneurs also undergo growth stages in many different areas of their lives. Entrepreneurs being individuals each have their own set of characteristics in terms of personality, leadership style, entrepreneurship type, skills, life stage and career stages. The challenge of an organisation is to create a strategy that best matches the expectations of all the entrepreneurs and members. The resources of the organisation need to be aligned in order to achieve the common strategy. The problem is as to how the organisation makes use of its leaders and entrepreneurs to achieve strategy; and how does it deal with inconsistencies in goals of entrepreneurs and shortfalls of specific skills or resources that it will require to sustain or grow the organisation?
- Full Text:
- Date Issued: 2010
- Authors: White, Andrew Stephen
- Date: 2010
- Subjects: Entrepreneurship
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8608 , http://hdl.handle.net/10948/1525 , Entrepreneurship
- Description: The strategy of the organisation and its entrepreneur’s expectations of the organisation should be aligned in order to create an environment in which all entrepreneurs are motivated and work towards common goals. Furthermore, the entrepreneur’s life stages and personal life plans should be synchronised with the needs of the organisation to achieve the goals. As organisations pass through different stages of growth; they require different resources to assist in progression to next stages. As with organisations and their growth phases; entrepreneurs also undergo growth stages in many different areas of their lives. Entrepreneurs being individuals each have their own set of characteristics in terms of personality, leadership style, entrepreneurship type, skills, life stage and career stages. The challenge of an organisation is to create a strategy that best matches the expectations of all the entrepreneurs and members. The resources of the organisation need to be aligned in order to achieve the common strategy. The problem is as to how the organisation makes use of its leaders and entrepreneurs to achieve strategy; and how does it deal with inconsistencies in goals of entrepreneurs and shortfalls of specific skills or resources that it will require to sustain or grow the organisation?
- Full Text:
- Date Issued: 2010
South African memoirs in a decade of transition: Athol Fugard's Cousins (1994), J.M. Coetzee's Boyhood (1997), and Breyten Breytenbach's Dog Heart (1999)
- Authors: Roux, Christine Ann
- Date: 2002
- Subjects: Autobiography , Fugard, Athol , Coetzee, J. M., 1940 , Breytenbach, Breyten
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2191 , http://hdl.handle.net/10962/d1002233 , Autobiography , Fugard, Athol , Coetzee, J. M., 1940 , Breytenbach, Breyten
- Description: This thesis examines three South African memoirs using M. M. Bakhtin’s theories of the dialogical relationship in language and literature. By offering an alternative to a postmodern or multicultural interpretation of autobiographies, Bakhtin’s precepts, that define a dialogic, help to reframe a way of discussing memoirs and avoiding dead-ends previously arrived at by essayists in James Olney’s 1980 collection. Bakhtin’s ideas discussed here, which include the “once-occurrent moment”, “architectonic contraposition”, ”emotional-volitional tone”, “alibi”, “non-alibi”, and “centripetal” and “centrifugal” force, help to rebuild a discussion based on temporary and evolving self truth rather than fiction, the postmodern interpretation, or confession, the new-age secular spiritualism based on multicultural and politically correct standards. For this, each author’s memoir had to be examined separately and a conclusion was arrived at through inductive analysis. Rather than try to find similar characteristics, I focused on what made each memoir different and unique. Janet Varner Gunn’s Autobiography: Toward A Poetics of Experience (1982) refocused the debate over autobiography on process. The question, what steps did each author take toward writing about himself, led the discussion to an examination of the priorities each author exemplified. Beginning with Fugard who emphasized spatial, concrete, and sensory detail to help him contain his emotional life, the thesis moves on to an examination of Coetzee’s sense of justice. From the physical and intellectual world follows Breytenbach’s spiritual space-making. In each memoir, control of space is evident on different levels of experience. Articulating space inevitably leads to a discussion of boundaries. Here, Charles Taylor’s emphasis on the modern self’s need to articulate a horizon or a framework is helpful in generalizing the effect of the autobiographical process. The conclusion reached is that autobiography is inherently centrifugal: it moves away from the center of cultural thinking because its “truth” bolsters itself on dialogical process which does not depend on a fixed authority but rather on communicative exchange. As an example of exchange, autobiography’s central truth is that it returns to a “unique point of origin”, namely the self, only to reconnect to the other in a potentially eternal exchange of responsiveness moving away from the center.
- Full Text:
- Date Issued: 2002
- Authors: Roux, Christine Ann
- Date: 2002
- Subjects: Autobiography , Fugard, Athol , Coetzee, J. M., 1940 , Breytenbach, Breyten
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2191 , http://hdl.handle.net/10962/d1002233 , Autobiography , Fugard, Athol , Coetzee, J. M., 1940 , Breytenbach, Breyten
- Description: This thesis examines three South African memoirs using M. M. Bakhtin’s theories of the dialogical relationship in language and literature. By offering an alternative to a postmodern or multicultural interpretation of autobiographies, Bakhtin’s precepts, that define a dialogic, help to reframe a way of discussing memoirs and avoiding dead-ends previously arrived at by essayists in James Olney’s 1980 collection. Bakhtin’s ideas discussed here, which include the “once-occurrent moment”, “architectonic contraposition”, ”emotional-volitional tone”, “alibi”, “non-alibi”, and “centripetal” and “centrifugal” force, help to rebuild a discussion based on temporary and evolving self truth rather than fiction, the postmodern interpretation, or confession, the new-age secular spiritualism based on multicultural and politically correct standards. For this, each author’s memoir had to be examined separately and a conclusion was arrived at through inductive analysis. Rather than try to find similar characteristics, I focused on what made each memoir different and unique. Janet Varner Gunn’s Autobiography: Toward A Poetics of Experience (1982) refocused the debate over autobiography on process. The question, what steps did each author take toward writing about himself, led the discussion to an examination of the priorities each author exemplified. Beginning with Fugard who emphasized spatial, concrete, and sensory detail to help him contain his emotional life, the thesis moves on to an examination of Coetzee’s sense of justice. From the physical and intellectual world follows Breytenbach’s spiritual space-making. In each memoir, control of space is evident on different levels of experience. Articulating space inevitably leads to a discussion of boundaries. Here, Charles Taylor’s emphasis on the modern self’s need to articulate a horizon or a framework is helpful in generalizing the effect of the autobiographical process. The conclusion reached is that autobiography is inherently centrifugal: it moves away from the center of cultural thinking because its “truth” bolsters itself on dialogical process which does not depend on a fixed authority but rather on communicative exchange. As an example of exchange, autobiography’s central truth is that it returns to a “unique point of origin”, namely the self, only to reconnect to the other in a potentially eternal exchange of responsiveness moving away from the center.
- Full Text:
- Date Issued: 2002
The design of a student resource centre in central Port Elizabeth
- Authors: Jacobs, Lize-Mari
- Date: 2016
- Subjects: Library architecture -- South Africa -- Port Elizabeth Libraries -- Space utilization , Library buildings -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MArch
- Identifier: http://hdl.handle.net/10948/18908 , vital:28748
- Description: The city centre of Port Elizabeth houses a large percentage of the city’s student population. The primary tertiary institution, the Nelson Mandela Metropolitan University, is decentralised from the city centre. Thus, many students sacrifice a lot of time and money travelling far distances between the campus and home every day. The treatise proposes a Student Resource Centre in Central Port Elizabeth as an appropriate building that will provide the students with appropriate learning spaces and access to resources in close proximity to home. The treatise seeks to understand the aspects that influence the design of learning spaces. Students and pedagogy are constantly changing within the current age of technology. Learning spaces should be designed to satisfy student needs and reinforce current pedagogy. The treatise also investigates the challenges and opportunities of an identified site located within a precinct that is inaccessible and in a state of urban decay that causes segregation within the city. The Student Resource Centre will act as a central gathering and learning space serving the many varied needs of the students within its constituency, while also positively contributing to the urban context of the city as a whole.
- Full Text:
- Date Issued: 2016
- Authors: Jacobs, Lize-Mari
- Date: 2016
- Subjects: Library architecture -- South Africa -- Port Elizabeth Libraries -- Space utilization , Library buildings -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MArch
- Identifier: http://hdl.handle.net/10948/18908 , vital:28748
- Description: The city centre of Port Elizabeth houses a large percentage of the city’s student population. The primary tertiary institution, the Nelson Mandela Metropolitan University, is decentralised from the city centre. Thus, many students sacrifice a lot of time and money travelling far distances between the campus and home every day. The treatise proposes a Student Resource Centre in Central Port Elizabeth as an appropriate building that will provide the students with appropriate learning spaces and access to resources in close proximity to home. The treatise seeks to understand the aspects that influence the design of learning spaces. Students and pedagogy are constantly changing within the current age of technology. Learning spaces should be designed to satisfy student needs and reinforce current pedagogy. The treatise also investigates the challenges and opportunities of an identified site located within a precinct that is inaccessible and in a state of urban decay that causes segregation within the city. The Student Resource Centre will act as a central gathering and learning space serving the many varied needs of the students within its constituency, while also positively contributing to the urban context of the city as a whole.
- Full Text:
- Date Issued: 2016
A trust based model for enhanced adoption of diabetes self-management mobile applications
- Authors: Mainoti, Ganizani Fidelis
- Date: 2018
- Subjects: Medical records -- Data processing Medical records -- Management Mobile communication systems
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10353/11041 , vital:37011
- Description: Information technology (IT) trust is an important concept as people today rely more on IT to perform their tasks than before. Extensive research in Information Systems (IS) has explored trust and how it affects clients’ selection of different IT artefacts. Literature found trust to be a key determinant of technology use and an accelerator of understanding user perceptions regarding technology. Users’ perception of a technology’s characteristics influences their initial decision to adopt it; they are less likely to try the technology once they perceive significant risk linked to the technology exploration. The study focused on trust in relation to adoption of mobile applications (apps) for self-management of diabetic treatment regimens. The aim was to identify factors that should be incorporated in these apps to positively influence user perception of trustworthiness for enhanced adoption. According to extant literature, there are a myriad of apps which are available and ready for use, but diabetic patients are not maximising these opportunities to actively participate in managing their conditions. This is in spite of the numerous benefits accruable from using these apps to aid treatment regimens away from clinical settings or with minimal involvement of health personnel. This work is a qualitative study that investigated the reasons behind the low levels of trust in mobile applications for self-management of diabetes. The research design involved a survey and the study employed interviews for primary data collection. Twenty participants were engaged in the intervention. Some of these respondents were diabetic patients on treatment and others were health staff specialising in diabetes treatment. The participants were asked to download and try, for one month or more, the Diabetes:M app from Google play store for android devices or from iTunes for IOS devices. Thereafter, interviews were held with the participants to investigate their perceptions of the diabetes management app. Based on the outcome of the investigation, the researcher put forward a model proposing the attributes of trustworthiness of diabetes self-management mobile apps for enhanced adoption. Research findings showed that the apps for diabetes self-management should be usable, possess sufficient functionalities, give accurate information for decision-making, be reliable, and secure in order to enhance the trust of diabetic patients.
- Full Text:
- Date Issued: 2018
- Authors: Mainoti, Ganizani Fidelis
- Date: 2018
- Subjects: Medical records -- Data processing Medical records -- Management Mobile communication systems
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10353/11041 , vital:37011
- Description: Information technology (IT) trust is an important concept as people today rely more on IT to perform their tasks than before. Extensive research in Information Systems (IS) has explored trust and how it affects clients’ selection of different IT artefacts. Literature found trust to be a key determinant of technology use and an accelerator of understanding user perceptions regarding technology. Users’ perception of a technology’s characteristics influences their initial decision to adopt it; they are less likely to try the technology once they perceive significant risk linked to the technology exploration. The study focused on trust in relation to adoption of mobile applications (apps) for self-management of diabetic treatment regimens. The aim was to identify factors that should be incorporated in these apps to positively influence user perception of trustworthiness for enhanced adoption. According to extant literature, there are a myriad of apps which are available and ready for use, but diabetic patients are not maximising these opportunities to actively participate in managing their conditions. This is in spite of the numerous benefits accruable from using these apps to aid treatment regimens away from clinical settings or with minimal involvement of health personnel. This work is a qualitative study that investigated the reasons behind the low levels of trust in mobile applications for self-management of diabetes. The research design involved a survey and the study employed interviews for primary data collection. Twenty participants were engaged in the intervention. Some of these respondents were diabetic patients on treatment and others were health staff specialising in diabetes treatment. The participants were asked to download and try, for one month or more, the Diabetes:M app from Google play store for android devices or from iTunes for IOS devices. Thereafter, interviews were held with the participants to investigate their perceptions of the diabetes management app. Based on the outcome of the investigation, the researcher put forward a model proposing the attributes of trustworthiness of diabetes self-management mobile apps for enhanced adoption. Research findings showed that the apps for diabetes self-management should be usable, possess sufficient functionalities, give accurate information for decision-making, be reliable, and secure in order to enhance the trust of diabetic patients.
- Full Text:
- Date Issued: 2018
Parents’ perceptions about male teachers’ underpresentation in the foundation phase : a study in the East London Education District
- Authors: Kewuti, Nomfihlakalo
- Date: 2018
- Subjects: Male preschool teachers
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/15914 , vital:40563
- Description: Foundation Phase in many schools is dominated by females and there are no or few male teachers in these grades. Foundation Phase comprises both boys and girls and if girls need female teachers to teach them, so the boys also need male teachers. One of the reasons why males do not want to teach in the Foundation Phase is the gender stereotype that Foundation Phase is a woman’s job, which deprive young learners the benefits that they could enjoy by having male teachers in their early years. The objectives of this study were to establish the parents’ perceptions about male teachers’ underrepresentation in the Foundation Phase; to determine how parents and their children can benefit from being taught by male teachers in the FP; to ascertain what challenges parents perceive are experienced by male teachers in the FP and to ascertain how SGB parent component can attract male teachers for FP teaching in their schools. The study was conducted in the East London Education District from three primary schools in urban, semi-urban and rural school settings. The schools selected were those that have male teachers in the FP in Grade R, 1, 2 and 3. A purposeful sample of nine parents who have children in male teacher classes in the Foundation Phase were used; three parents from each school. Qualitative data were generated through semi-structured interviews and observations, using phenomenology design. Thematic analysis was conducted on the basis of the themes that emerged from the participants’ responses to the research questions. This study adopted an interpretive paradigm to get an understanding of parents’ perceptions about male teachers’ underrepresentation in the FP from parents who have children in the male teacher classes in the FP. The findings indicated that parents feel a need for male teachers in the FP to act as disciplinarians. They also noted that their children who are taught by male teachers have good behaviours. Benefits like gender equality, improvement in sports, confidence of learners in doing their work and grooming and balancing for higher levels. It has appeared that parents also understand that male teachers experience challenges of being unaccepted by the parents of learners and also by their female colleagues. These challenges stem from the fact that teaching in FP is associated with being nannies which is a female duty; males are associated with child abuse and are thought to be paedophiles and there a great lack of trust due to these associations pointed at them. Parents in their responses have shown that they are for the view that the SGB parent component should ensure that male teachers are employed in the FP by recommending them (male teachers) in the posts at Foundation Phase level and that it should be adopted in their schools.
- Full Text:
- Date Issued: 2018
- Authors: Kewuti, Nomfihlakalo
- Date: 2018
- Subjects: Male preschool teachers
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/15914 , vital:40563
- Description: Foundation Phase in many schools is dominated by females and there are no or few male teachers in these grades. Foundation Phase comprises both boys and girls and if girls need female teachers to teach them, so the boys also need male teachers. One of the reasons why males do not want to teach in the Foundation Phase is the gender stereotype that Foundation Phase is a woman’s job, which deprive young learners the benefits that they could enjoy by having male teachers in their early years. The objectives of this study were to establish the parents’ perceptions about male teachers’ underrepresentation in the Foundation Phase; to determine how parents and their children can benefit from being taught by male teachers in the FP; to ascertain what challenges parents perceive are experienced by male teachers in the FP and to ascertain how SGB parent component can attract male teachers for FP teaching in their schools. The study was conducted in the East London Education District from three primary schools in urban, semi-urban and rural school settings. The schools selected were those that have male teachers in the FP in Grade R, 1, 2 and 3. A purposeful sample of nine parents who have children in male teacher classes in the Foundation Phase were used; three parents from each school. Qualitative data were generated through semi-structured interviews and observations, using phenomenology design. Thematic analysis was conducted on the basis of the themes that emerged from the participants’ responses to the research questions. This study adopted an interpretive paradigm to get an understanding of parents’ perceptions about male teachers’ underrepresentation in the FP from parents who have children in the male teacher classes in the FP. The findings indicated that parents feel a need for male teachers in the FP to act as disciplinarians. They also noted that their children who are taught by male teachers have good behaviours. Benefits like gender equality, improvement in sports, confidence of learners in doing their work and grooming and balancing for higher levels. It has appeared that parents also understand that male teachers experience challenges of being unaccepted by the parents of learners and also by their female colleagues. These challenges stem from the fact that teaching in FP is associated with being nannies which is a female duty; males are associated with child abuse and are thought to be paedophiles and there a great lack of trust due to these associations pointed at them. Parents in their responses have shown that they are for the view that the SGB parent component should ensure that male teachers are employed in the FP by recommending them (male teachers) in the posts at Foundation Phase level and that it should be adopted in their schools.
- Full Text:
- Date Issued: 2018
Multi-temporal analysis of changes in vegetation distribution in the Great Fish River Game Reserve, Eastern Cape Province, South Africa :1982-2012
- Authors: Dikweni, Sipho
- Date: 2018
- Subjects: Climatic changes -- South Africa|zEastern Cape Biodiversity conservation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10511 , vital:35550
- Description: Great Fish River Game Reserve plays an important role in curtailing the ever-increasing biodiversity declines in Eastern Cape Province and South Africa at large. Though this area plays an important role in the conservation of natural biodiversity, it has been observed that it is undergoing considerable changes with regards to conditions and composition of vegetation cover. These changes signal a decline in the capacity of the Great Fish River Game Reserve to support wildlife population. In this study, remote sensing was used to investigate multi-temporal changes in vegetation distribution in this particular reserve over a period of 30 years (1982-2012). A supervised classification was carried out to classify four Landsat images including; Landsat TM, Landsat ETM and Landsat 8 imagery of 1984, 1992, 2002 and 2013 respectively to map historical and present vegetation conditions and distribution in the Great Fish River Game Reserve. A comparative examination of the classified images showed that there were significant changes in the composition and structure of vegetation with much of the palatable plant species being driven to extinction. The results showed that herbivory pressure inconjuction with climate variability has subsequently resulted in a decrease of the supporting potential of the reserve to sustain wildlife due to mortality of the most preferred plant species and abundant increase of non-palatable plant species. As grazing and browsing intensity increased, there was a decline in regenerative potential of the selected plant species by wild herbivores and successful increase in abundance of the non-palatable plant species. The results of this investigation suggest that the current increase in wildlife population will facilitate the deterioration of habitat condition to support wildlife up to the point of no recovery.
- Full Text:
- Date Issued: 2018
- Authors: Dikweni, Sipho
- Date: 2018
- Subjects: Climatic changes -- South Africa|zEastern Cape Biodiversity conservation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10511 , vital:35550
- Description: Great Fish River Game Reserve plays an important role in curtailing the ever-increasing biodiversity declines in Eastern Cape Province and South Africa at large. Though this area plays an important role in the conservation of natural biodiversity, it has been observed that it is undergoing considerable changes with regards to conditions and composition of vegetation cover. These changes signal a decline in the capacity of the Great Fish River Game Reserve to support wildlife population. In this study, remote sensing was used to investigate multi-temporal changes in vegetation distribution in this particular reserve over a period of 30 years (1982-2012). A supervised classification was carried out to classify four Landsat images including; Landsat TM, Landsat ETM and Landsat 8 imagery of 1984, 1992, 2002 and 2013 respectively to map historical and present vegetation conditions and distribution in the Great Fish River Game Reserve. A comparative examination of the classified images showed that there were significant changes in the composition and structure of vegetation with much of the palatable plant species being driven to extinction. The results showed that herbivory pressure inconjuction with climate variability has subsequently resulted in a decrease of the supporting potential of the reserve to sustain wildlife due to mortality of the most preferred plant species and abundant increase of non-palatable plant species. As grazing and browsing intensity increased, there was a decline in regenerative potential of the selected plant species by wild herbivores and successful increase in abundance of the non-palatable plant species. The results of this investigation suggest that the current increase in wildlife population will facilitate the deterioration of habitat condition to support wildlife up to the point of no recovery.
- Full Text:
- Date Issued: 2018
Indicators of household-level vunerability to climate change in three topographically diverse rural villages
- Authors: Sotsha, Kayalethu
- Date: 2013
- Subjects: Poverty -- South Africa , Land tenure -- South Africa , Climatic changes -- South Africa , Farms, Small -- South Africa , Rural poor -- South Africa
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11212 , http://hdl.handle.net/10353/d1016204 , Poverty -- South Africa , Land tenure -- South Africa , Climatic changes -- South Africa , Farms, Small -- South Africa , Rural poor -- South Africa
- Description: Climate change has become a major concern globally and it clearly exerts a profound influence on the lives of poor rural populations who depend on agriculture for livelihoods.Generally, agriculture is more at risk from weather, pests and diseases than is industry or trade. Furthermore, many farming units are at low levels of development with little technological input in their production systems. This makes them vulnerable to any exposure to climate and environmental variation, given that there is little capacity for the system to adjust to change. Most at risk are the rural poor with low levels of development and limited ability to adapt to and overcome the effects of climate change. Using data from a sample survey of 120 households this study attempts to assess and compare indicators of vulnerability to climate change. The comparison was made at household level between three typical villages, an inland, a river catchment and a coastal village. This idea of comparison arises from the general understanding that different variables affect different regions differently so that the impact of and vulnerability to climate change differs across regions, areas and populations. The data was obtained using a questionnaire that was administered through face-to-face interviews. Given that sensitivity and adaptive capacity of farming systems to climate change is shaped by both socioeconomic and institutional factors, a multiple regression model was used to test the relationship between indicators of vulnerability and household socioeconomic and institutional characteristics. Indicators were selected based on significant statistical relationships. This means that the statistical procedure for selecting indicators involved relating a large number of variables to vulnerability in order to identify statistically significant factors. The results showed reliability of income and reliability of water resources to be good indicators of vulnerability. Many statistically significant variables as well as respective R2 of 0.988 and 0.825 confirm the foregoing. Another indicator was the Simpson index that measures diversification of agricultural production. The results show that vulnerability to climate change was highest for the households near the river and lowest for the inland village. Moreover, the results confirmed that most blacks that are practicing agriculture receive little if any support largely because available resources are highly skewed towards certain farmers rather than others.
- Full Text:
- Date Issued: 2013
- Authors: Sotsha, Kayalethu
- Date: 2013
- Subjects: Poverty -- South Africa , Land tenure -- South Africa , Climatic changes -- South Africa , Farms, Small -- South Africa , Rural poor -- South Africa
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11212 , http://hdl.handle.net/10353/d1016204 , Poverty -- South Africa , Land tenure -- South Africa , Climatic changes -- South Africa , Farms, Small -- South Africa , Rural poor -- South Africa
- Description: Climate change has become a major concern globally and it clearly exerts a profound influence on the lives of poor rural populations who depend on agriculture for livelihoods.Generally, agriculture is more at risk from weather, pests and diseases than is industry or trade. Furthermore, many farming units are at low levels of development with little technological input in their production systems. This makes them vulnerable to any exposure to climate and environmental variation, given that there is little capacity for the system to adjust to change. Most at risk are the rural poor with low levels of development and limited ability to adapt to and overcome the effects of climate change. Using data from a sample survey of 120 households this study attempts to assess and compare indicators of vulnerability to climate change. The comparison was made at household level between three typical villages, an inland, a river catchment and a coastal village. This idea of comparison arises from the general understanding that different variables affect different regions differently so that the impact of and vulnerability to climate change differs across regions, areas and populations. The data was obtained using a questionnaire that was administered through face-to-face interviews. Given that sensitivity and adaptive capacity of farming systems to climate change is shaped by both socioeconomic and institutional factors, a multiple regression model was used to test the relationship between indicators of vulnerability and household socioeconomic and institutional characteristics. Indicators were selected based on significant statistical relationships. This means that the statistical procedure for selecting indicators involved relating a large number of variables to vulnerability in order to identify statistically significant factors. The results showed reliability of income and reliability of water resources to be good indicators of vulnerability. Many statistically significant variables as well as respective R2 of 0.988 and 0.825 confirm the foregoing. Another indicator was the Simpson index that measures diversification of agricultural production. The results show that vulnerability to climate change was highest for the households near the river and lowest for the inland village. Moreover, the results confirmed that most blacks that are practicing agriculture receive little if any support largely because available resources are highly skewed towards certain farmers rather than others.
- Full Text:
- Date Issued: 2013
Exploring user experience (UX) factors For ICTD services
- Authors: Nyambi, Pride Bongiwe
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11400 , http://hdl.handle.net/10353/d1020164
- Description: Consistent with global entities such as the United Nations- through the World Summit of the Information Society (WSIS), introduction of Information and Communication Technology (ICT) for human development has seen the introduction of ICT-based services aimed at facilitating socio-economic development of marginalized communities. The use of ICTs has always solicited the concept of Human Computer Interaction (HCI), which involves the methods which humans interact with technology. The types of User Interfaces (UIs) and interaction techniques that people use to interact with ICTs affects the way they perceive technology and eventually, their acceptance of the technology. Current ICT systems still haven‟t adopted the concept of placing the user at the core of the interaction. Users are still required to adapt themselves to the interface‟s characteristics; which limits the number of people who can use the system due to inabilities to adapt to the interface. As a result, the information embedded in these technologies is still inaccessible and useless to Marginalized Rural Area (MRA) users. Such usability challenges can be mitigated against and avoided by matching UI components with the users‟ mental models, language, preferences, needs and other socio-cultural artefacts. In this research, literature in Human-Computer Interaction (HCI) is reviewed with emphasis on the usability and User Experience (UX) during user interaction with ICTs using various modes of interactions. HCI emphasizes the need for systems to take account of user‟s characteristics such as their abilities, needs, socio-cultural experiences, behaviours and interests. In efforts to meet the requirement of UX, the user, system and the context of use, need to be evaluated, taking into consideration that changing one entity modifies the UX. This will be achieved by persona profiling to determine the key characteristics of the user communities, clustered according to the key UX attributes. Subsequently, through detailed usability evaluations, including the use of System Usability Scale (SUS) to determine user satisfaction with various UI components/techniques per identified persona- thus providing and persona mapping for usability of Information and Communication Technology for Development (ICTD) services. The results from this research are reflective of the importance of creating personas for usability testing. Some of the personas do not have a problem with interacting with most of the interfaces but their choice of interface comes from a preference point of view. For some personas, their skills and level of experience with ICTs motivates their choice of interface. The common UI component that users from across the spectrum appreciate is UI consistency which makes interaction easier and more natural. Common obstacles with current User Interfaces (UIs) that inhibit users from MRAs include the hefty use of text in interfaces, unintuitive navigation structures and the use of a foreign language. Differences in UIs from different application developers present an inconsistency which challenges the users from rural areas. These differences include the layout, the text entry methods and the form of output produced. A solution to this has been identified from the usability test as the use of speech-enabled interfaces in a language that can be understood by the target audience. In addition, through literature study it has been found that UX of interfaces can be improved by the use of less textual or text-free interfaces. Based on literature, users from MRAs can benefit from using hand-writing based UIs for text-based entry which mimics pen and paper environment for literate users who have experience with writing. Finally, the use of numbered options can assist illiterate users in tasks that requires users to choose options and for navigation. Therefore, consistency in UIs designed to be used by MRA users can improve usability of these interfaces and thus, improving the overall UX.
- Full Text:
- Date Issued: 2015
- Authors: Nyambi, Pride Bongiwe
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11400 , http://hdl.handle.net/10353/d1020164
- Description: Consistent with global entities such as the United Nations- through the World Summit of the Information Society (WSIS), introduction of Information and Communication Technology (ICT) for human development has seen the introduction of ICT-based services aimed at facilitating socio-economic development of marginalized communities. The use of ICTs has always solicited the concept of Human Computer Interaction (HCI), which involves the methods which humans interact with technology. The types of User Interfaces (UIs) and interaction techniques that people use to interact with ICTs affects the way they perceive technology and eventually, their acceptance of the technology. Current ICT systems still haven‟t adopted the concept of placing the user at the core of the interaction. Users are still required to adapt themselves to the interface‟s characteristics; which limits the number of people who can use the system due to inabilities to adapt to the interface. As a result, the information embedded in these technologies is still inaccessible and useless to Marginalized Rural Area (MRA) users. Such usability challenges can be mitigated against and avoided by matching UI components with the users‟ mental models, language, preferences, needs and other socio-cultural artefacts. In this research, literature in Human-Computer Interaction (HCI) is reviewed with emphasis on the usability and User Experience (UX) during user interaction with ICTs using various modes of interactions. HCI emphasizes the need for systems to take account of user‟s characteristics such as their abilities, needs, socio-cultural experiences, behaviours and interests. In efforts to meet the requirement of UX, the user, system and the context of use, need to be evaluated, taking into consideration that changing one entity modifies the UX. This will be achieved by persona profiling to determine the key characteristics of the user communities, clustered according to the key UX attributes. Subsequently, through detailed usability evaluations, including the use of System Usability Scale (SUS) to determine user satisfaction with various UI components/techniques per identified persona- thus providing and persona mapping for usability of Information and Communication Technology for Development (ICTD) services. The results from this research are reflective of the importance of creating personas for usability testing. Some of the personas do not have a problem with interacting with most of the interfaces but their choice of interface comes from a preference point of view. For some personas, their skills and level of experience with ICTs motivates their choice of interface. The common UI component that users from across the spectrum appreciate is UI consistency which makes interaction easier and more natural. Common obstacles with current User Interfaces (UIs) that inhibit users from MRAs include the hefty use of text in interfaces, unintuitive navigation structures and the use of a foreign language. Differences in UIs from different application developers present an inconsistency which challenges the users from rural areas. These differences include the layout, the text entry methods and the form of output produced. A solution to this has been identified from the usability test as the use of speech-enabled interfaces in a language that can be understood by the target audience. In addition, through literature study it has been found that UX of interfaces can be improved by the use of less textual or text-free interfaces. Based on literature, users from MRAs can benefit from using hand-writing based UIs for text-based entry which mimics pen and paper environment for literate users who have experience with writing. Finally, the use of numbered options can assist illiterate users in tasks that requires users to choose options and for navigation. Therefore, consistency in UIs designed to be used by MRA users can improve usability of these interfaces and thus, improving the overall UX.
- Full Text:
- Date Issued: 2015
The potential of Elephantorrhiza elephantina as an anthelmintic of goats in the Eastern Cape province, South Africa
- Authors: Mazhangara, Irene Rumbidza
- Date: 2017
- Subjects: Bioactive compounds -- South Africa -- Eastern Cape Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15068 , vital:40160
- Description: The main objective of the study was to investigate the potential of Elephantorrhiza elephantina in the control of gastro-intestinal worms in goats in the Eastern Cape Province, South Africa. The ethanolic, methanolic and aqueous phytochemical composition of E. elephantina root bark extracts were determined. The phytochemical analysis revealed a high concentration of alkaloids, condensed tannins, flavonoids, phenols and saponins in E. elephantina root extracts. Quantitative phytochemical analysis of alkaloids in water extract was 932.44 ± 1.23 mg. Condensed tannins, phenols and saponins in ethanol extract were 450.52 ± 4.56 mg CE/g, 476.11 ± 0.03 mg GAE/g and 832.85 ± 1.45 mg respectively. Flavonoids was 803.93 ± 0.02 mg QE/g in methanol extract as the highest recordings. In vitro screening of ethanol, methanol and water extracts of E. elephantina for potential anthelminthic activity against adult Paramphistomum cervi worm motility showed time and dose-dependent significant effects after 12 hours of treatment. Ethanolic extracts showed a highly significant (P < 0.05) inhibition of motility (86.67 and 96.67 percent) at concentrations 7.5 and 15 mg/ml, respectively. Methanolic and aqueous extracts exhibited a significant (P < 0.05) motility inhibition (96.67 and 66.67 percent, respectively) at concentration of 15 mg/ml 16 hours post-exposure. In vitro assessment of structural changes to adult gastro-intestinal worms following exposure to E. elephantina extracts was done using scanning electron microscopy (SEM). The SEM observations revealed structural changes in the worms after contact with E. elephantina extracts in comparison with the control worms kept in Phosphate-buffered saline (PBS). The major alterations were around the cuticle, posterior and anterior areas. These changes included longitudinal and transversal folds and thicker cuticula ridges, material aggregates around the posterior and anterior areas. The study showed that ethanol, methanol and water extracts of E. elephantina root contained significant amounts of alkaloids, condensed tannins, flavanoids, phenols and saponins. Validation studies showed that extracts of E. elephantina possess anthelminthic activities. The structural changes found in the worms exposed to extracts of E. elephantina root extracts affected their motility and nutrition, resulting in mortality.
- Full Text:
- Date Issued: 2017
- Authors: Mazhangara, Irene Rumbidza
- Date: 2017
- Subjects: Bioactive compounds -- South Africa -- Eastern Cape Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15068 , vital:40160
- Description: The main objective of the study was to investigate the potential of Elephantorrhiza elephantina in the control of gastro-intestinal worms in goats in the Eastern Cape Province, South Africa. The ethanolic, methanolic and aqueous phytochemical composition of E. elephantina root bark extracts were determined. The phytochemical analysis revealed a high concentration of alkaloids, condensed tannins, flavonoids, phenols and saponins in E. elephantina root extracts. Quantitative phytochemical analysis of alkaloids in water extract was 932.44 ± 1.23 mg. Condensed tannins, phenols and saponins in ethanol extract were 450.52 ± 4.56 mg CE/g, 476.11 ± 0.03 mg GAE/g and 832.85 ± 1.45 mg respectively. Flavonoids was 803.93 ± 0.02 mg QE/g in methanol extract as the highest recordings. In vitro screening of ethanol, methanol and water extracts of E. elephantina for potential anthelminthic activity against adult Paramphistomum cervi worm motility showed time and dose-dependent significant effects after 12 hours of treatment. Ethanolic extracts showed a highly significant (P < 0.05) inhibition of motility (86.67 and 96.67 percent) at concentrations 7.5 and 15 mg/ml, respectively. Methanolic and aqueous extracts exhibited a significant (P < 0.05) motility inhibition (96.67 and 66.67 percent, respectively) at concentration of 15 mg/ml 16 hours post-exposure. In vitro assessment of structural changes to adult gastro-intestinal worms following exposure to E. elephantina extracts was done using scanning electron microscopy (SEM). The SEM observations revealed structural changes in the worms after contact with E. elephantina extracts in comparison with the control worms kept in Phosphate-buffered saline (PBS). The major alterations were around the cuticle, posterior and anterior areas. These changes included longitudinal and transversal folds and thicker cuticula ridges, material aggregates around the posterior and anterior areas. The study showed that ethanol, methanol and water extracts of E. elephantina root contained significant amounts of alkaloids, condensed tannins, flavanoids, phenols and saponins. Validation studies showed that extracts of E. elephantina possess anthelminthic activities. The structural changes found in the worms exposed to extracts of E. elephantina root extracts affected their motility and nutrition, resulting in mortality.
- Full Text:
- Date Issued: 2017
Electrospun nanofibers as solid phase extraction sorbents and support for alkylphenols colorimetric probes
- Authors: Tancu, Yolanda
- Date: 2014
- Subjects: Nanofibers , Electrospinning , Extraction (Chemistry) , Sorbents , Phenols , Colorimetry , Transmission electron microscopy , High resolution spectroscopy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4486 , http://hdl.handle.net/10962/d1012997
- Description: The thesis reports on fabricating alternative solid phase extraction (SPE) sorbents and colorimetric probes based on electrospun nanofibers for alkylphenols (APs). Hydroxyl methylated styrene [poly(co-styrene-CH₃OH)] and 3-oxobutanoate styrene [poly(co-styrene-OCOCH₃COCH₃)] copolymers were synthesized and fabricated into sorbent materials by electro-spinning/spraying. The fabricated morphologies consisting of bead free fibers, beaded fibers and particles were evaluated as SPE sorbents using batch experiments. Electropun fibers proved to be better sorbents as they exhibited extraction efficiency that exceeded 95% compared to 60% for beaded fibers and 40% for particles. In view to reduce sample and solvent volumes, smooth fibers were packed into pipette tips as SPE devices that yielded quantitative recoveries of APs from spiked wastewater samples. Recoveries ranged from 70% to 125% with LOD of 0.008, 0.01 and 0.1 μg mL⁻¹ for 4-tert octylphenol (4-t-OP), 4-octylphenol (4-OP) and 4-nonylphenol (4-NP) respectively, when using high performance liquid chromatography-fluorescence detector (HPLC-FLD). Furthermore, amino functionalised polydiacetylene polymers (PDAs), citrate capped gold (AuNPs) and silver nanoparticles (AgNPs) were evaluated as colorimetric probes for visual detection of APs. In colloidal studies, AuNPs probe showed a colour change from wine red to green upon introduction of analyte. UV-vis spectroscopy revealed the shifting of the surface plasmon resonance (SPR) peak from 525 nm to 729 nm induced by aggregation of AuNPs. For AgNPs probe, a colour change was observed from yellowish green to brown. Transmission electron microscopy (TEM) studies showed growth of AgNPs. A presumed oxidation of the analyte, forming an absorbing compound at 279 nm in both AgNPs and PDAs probes was also observed. For PDAs probe the colour change was from purple to pink. Concentrations as low as 30 μg mL⁻¹ were detectable in all colloidal based probes. Further colorimetric investigations were conducted with electrospun AuNPs-nylon 6 fiber mat. A colour change from purplish red to navy blue at concentrations of 1000 μg mL⁻¹ was observed. Electrospun AgNPs –nylon 6 fiber mat did not show a distinct colour change. High resolution scanning electron microscopy (HRSEM) revealed the analyte inducing the assembly of AuNPs and AgNPs as they covered the surface of the nanofiber mat. Electrospun nanofibers are a platform for analysis and thus tuning their chemistry will lead to sensitive and selective methods
- Full Text:
- Date Issued: 2014
- Authors: Tancu, Yolanda
- Date: 2014
- Subjects: Nanofibers , Electrospinning , Extraction (Chemistry) , Sorbents , Phenols , Colorimetry , Transmission electron microscopy , High resolution spectroscopy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4486 , http://hdl.handle.net/10962/d1012997
- Description: The thesis reports on fabricating alternative solid phase extraction (SPE) sorbents and colorimetric probes based on electrospun nanofibers for alkylphenols (APs). Hydroxyl methylated styrene [poly(co-styrene-CH₃OH)] and 3-oxobutanoate styrene [poly(co-styrene-OCOCH₃COCH₃)] copolymers were synthesized and fabricated into sorbent materials by electro-spinning/spraying. The fabricated morphologies consisting of bead free fibers, beaded fibers and particles were evaluated as SPE sorbents using batch experiments. Electropun fibers proved to be better sorbents as they exhibited extraction efficiency that exceeded 95% compared to 60% for beaded fibers and 40% for particles. In view to reduce sample and solvent volumes, smooth fibers were packed into pipette tips as SPE devices that yielded quantitative recoveries of APs from spiked wastewater samples. Recoveries ranged from 70% to 125% with LOD of 0.008, 0.01 and 0.1 μg mL⁻¹ for 4-tert octylphenol (4-t-OP), 4-octylphenol (4-OP) and 4-nonylphenol (4-NP) respectively, when using high performance liquid chromatography-fluorescence detector (HPLC-FLD). Furthermore, amino functionalised polydiacetylene polymers (PDAs), citrate capped gold (AuNPs) and silver nanoparticles (AgNPs) were evaluated as colorimetric probes for visual detection of APs. In colloidal studies, AuNPs probe showed a colour change from wine red to green upon introduction of analyte. UV-vis spectroscopy revealed the shifting of the surface plasmon resonance (SPR) peak from 525 nm to 729 nm induced by aggregation of AuNPs. For AgNPs probe, a colour change was observed from yellowish green to brown. Transmission electron microscopy (TEM) studies showed growth of AgNPs. A presumed oxidation of the analyte, forming an absorbing compound at 279 nm in both AgNPs and PDAs probes was also observed. For PDAs probe the colour change was from purple to pink. Concentrations as low as 30 μg mL⁻¹ were detectable in all colloidal based probes. Further colorimetric investigations were conducted with electrospun AuNPs-nylon 6 fiber mat. A colour change from purplish red to navy blue at concentrations of 1000 μg mL⁻¹ was observed. Electrospun AgNPs –nylon 6 fiber mat did not show a distinct colour change. High resolution scanning electron microscopy (HRSEM) revealed the analyte inducing the assembly of AuNPs and AgNPs as they covered the surface of the nanofiber mat. Electrospun nanofibers are a platform for analysis and thus tuning their chemistry will lead to sensitive and selective methods
- Full Text:
- Date Issued: 2014
Characterisation of the HSP70-HSP90 organising protein gene and its link to cancer
- Authors: Weeks, Stacey
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/56006 , vital:26764
- Description: HOP (Heat shock protein 70/ Heat shock protein 90 organising protein) is a co-chaperone essential for client protein transfer from HSP70 to HSP90 within the HSP90 chaperone machine and has been found to be up-regulated in various cancers. However, minimal in vitro information can be found on the regulation of HOP expression. The aim of this study was to analyse the HOP gene structure across known orthologues, identify and characterise the HOP promoter, and identify the regulatory mechanisms influencing the expression of HOP in cancer. We hypothesized that the expression of HOP in cancer cells is likely regulated by oncogenic signalling pathways linked to cis-elements within the HOP promoter. An initial study of the evolution of the HOP gene speciation was performed across identified orthologues using Mega5.2. The evolutionary pathway of the HOP gene was traced from the unicellular organisms to fish, to amphibian and then to land mammal. The synteny across the orthologues was identified and the co-expression profile of HOP analysed. We identified the putative promoter region for HOP in silico and in vitro. Luciferase reporter assays were utilized to demonstrate promoter activity of the upstream region in vitro. Bioinformatic analysis of the active promoter region identified a large CpG island and a range of putative cis-elements. Many of the cis-elements interact with transcription factors which are activated by oncogenic pathways. We therefore tested the regulation of HOP levels by rat sarcoma viral oncogene homologue (RAS). Cancer cell lines were transfected with mutated RAS to observe the effect of constitutively active RAS expression on the production of HOP using qRT-PCR and Western Blot analyses. Additionally, inhibitors of the RAS signalling pathway were utilised to confirm the regulatory effect of mutated RAS on HOP expression. In cancer cell lines containing mutated RAS (Hs578T), HOP was up-regulated via a mechanism involving the MAPK signalling pathway and the ETS-1 and C/EBPβ cis-elements within the HOP promoter. These findings suggest for the first time that Hop expression in cancer may be regulated by RAS activation of the HOP promoter. Additionally, this study allowed us to determine the murine system to be the most suited genetic model organism with which to study the function of human HOP.
- Full Text:
- Date Issued: 2015
- Authors: Weeks, Stacey
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/56006 , vital:26764
- Description: HOP (Heat shock protein 70/ Heat shock protein 90 organising protein) is a co-chaperone essential for client protein transfer from HSP70 to HSP90 within the HSP90 chaperone machine and has been found to be up-regulated in various cancers. However, minimal in vitro information can be found on the regulation of HOP expression. The aim of this study was to analyse the HOP gene structure across known orthologues, identify and characterise the HOP promoter, and identify the regulatory mechanisms influencing the expression of HOP in cancer. We hypothesized that the expression of HOP in cancer cells is likely regulated by oncogenic signalling pathways linked to cis-elements within the HOP promoter. An initial study of the evolution of the HOP gene speciation was performed across identified orthologues using Mega5.2. The evolutionary pathway of the HOP gene was traced from the unicellular organisms to fish, to amphibian and then to land mammal. The synteny across the orthologues was identified and the co-expression profile of HOP analysed. We identified the putative promoter region for HOP in silico and in vitro. Luciferase reporter assays were utilized to demonstrate promoter activity of the upstream region in vitro. Bioinformatic analysis of the active promoter region identified a large CpG island and a range of putative cis-elements. Many of the cis-elements interact with transcription factors which are activated by oncogenic pathways. We therefore tested the regulation of HOP levels by rat sarcoma viral oncogene homologue (RAS). Cancer cell lines were transfected with mutated RAS to observe the effect of constitutively active RAS expression on the production of HOP using qRT-PCR and Western Blot analyses. Additionally, inhibitors of the RAS signalling pathway were utilised to confirm the regulatory effect of mutated RAS on HOP expression. In cancer cell lines containing mutated RAS (Hs578T), HOP was up-regulated via a mechanism involving the MAPK signalling pathway and the ETS-1 and C/EBPβ cis-elements within the HOP promoter. These findings suggest for the first time that Hop expression in cancer may be regulated by RAS activation of the HOP promoter. Additionally, this study allowed us to determine the murine system to be the most suited genetic model organism with which to study the function of human HOP.
- Full Text:
- Date Issued: 2015
Cluster centre principals' perceptions of the implementation of the school cluster system in Namibia
- Authors: Aipinge, Lydia P
- Date: 2008
- Subjects: School management and organization -- Namibia Education -- Namibia School principals -- Namibia Educational leadership -- Namibia Educational change -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1449 , http://hdl.handle.net/10962/d1003330
- Description: The School Clustering System (SCS) was introduced five years after Namibia’s independence in 1990. The rationale for its implementation was to improve the quality of education in Namibian schools by enabling the sharing of resources, experience and expertise among clusters and facilitating school administration by pooling resources from several schools to be shared equally. It was piloted in Rundu and then gradually expanded to the whole country. The cluster system groups 5-7 schools that are eographically close and accessible to each other in one cluster under the leadership of one of the principals known as a Cluster Centre Principal (CCP). The purpose of this study was to investigate the perceptions of CCPs of the implementation of the SCS in two clusters of a particular circuit in the Omusati region. It is a case study involving two CCPs, one serving Inspector of Education (IE), a former Inspector of Education, several teachers, principals and parents. Data were collected through interviews, document analysis, and focus group discussions. The study found that the practice of cluster leaders is informed by contemporary leadership and management thinking. The participatory approach employed in clusterbased committees enables site-based management and collaboration. This has led to organisational learning. It was also found that a number of challenges are hampering the implementation of the SCS. These include lack of system support and inadequate resources. However, the human potential coupled with a high degree of readiness exhibited by cluster members are seen as potential drivers of further development of the system. The study recommends the adoption of a national policy that formalises the SCS as well as the strengthening of system support to build cluster capacity. It also makes suggestions for further research in organisational culture and behaviour with the aim of developing leadership and management practices in the SCS.
- Full Text:
- Date Issued: 2008
Cluster centre principals' perceptions of the implementation of the school cluster system in Namibia
- Authors: Aipinge, Lydia P
- Date: 2008
- Subjects: School management and organization -- Namibia Education -- Namibia School principals -- Namibia Educational leadership -- Namibia Educational change -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1449 , http://hdl.handle.net/10962/d1003330
- Description: The School Clustering System (SCS) was introduced five years after Namibia’s independence in 1990. The rationale for its implementation was to improve the quality of education in Namibian schools by enabling the sharing of resources, experience and expertise among clusters and facilitating school administration by pooling resources from several schools to be shared equally. It was piloted in Rundu and then gradually expanded to the whole country. The cluster system groups 5-7 schools that are eographically close and accessible to each other in one cluster under the leadership of one of the principals known as a Cluster Centre Principal (CCP). The purpose of this study was to investigate the perceptions of CCPs of the implementation of the SCS in two clusters of a particular circuit in the Omusati region. It is a case study involving two CCPs, one serving Inspector of Education (IE), a former Inspector of Education, several teachers, principals and parents. Data were collected through interviews, document analysis, and focus group discussions. The study found that the practice of cluster leaders is informed by contemporary leadership and management thinking. The participatory approach employed in clusterbased committees enables site-based management and collaboration. This has led to organisational learning. It was also found that a number of challenges are hampering the implementation of the SCS. These include lack of system support and inadequate resources. However, the human potential coupled with a high degree of readiness exhibited by cluster members are seen as potential drivers of further development of the system. The study recommends the adoption of a national policy that formalises the SCS as well as the strengthening of system support to build cluster capacity. It also makes suggestions for further research in organisational culture and behaviour with the aim of developing leadership and management practices in the SCS.
- Full Text:
- Date Issued: 2008
"Holy baptism" : a reconsideration of the doctrine of holy baptism in the light of recent research
- Authors: Moore, Robert Humphrey
- Date: 1974
- Subjects: Baptism in the Holy Spirit , Holy Spirit -- Biblical teaching
- Language: English
- Type: Thesis , Bachelor , BDiv
- Identifier: vital:1239 , http://hdl.handle.net/10962/d1007686 , Baptism in the Holy Spirit , Holy Spirit -- Biblical teaching
- Description: Conclusion: This study has helped us to perceive the significance of Christian Baptism as it arose from its antecedents, and yet differed decisively from them in meaning and significance. We have seen how Baptism grew from the New Testament situation into the life of the Early Church. We have considered the sacramental nature of Baptism, that here, while the Community is visibly active, in this holy sacrament, God is the doer of what is done. It is by Him, whose Grace is seen in Jesus Christ, that we are brought to new life within the Community of His Covenant and what He can do for adults, He can do for infants as well. However, it is good for us to remember that His presence is also for our judgement, and that there therefore remains upon us as individuals and as Community the requirement of faith and faithfulness. We have seen how it is that the Holy Spirit is given in Baptism, and we believe it is through His indwelling presence and power that we are able to come into the Family of God and enjoy that fellowship with Him, which is salvation. We have also seen that, despite many centuries of thought and study, no final doctrinal definition of Baptism is yet achieved, and that the Churches are still giving this serious attention.
- Full Text:
- Date Issued: 1974
- Authors: Moore, Robert Humphrey
- Date: 1974
- Subjects: Baptism in the Holy Spirit , Holy Spirit -- Biblical teaching
- Language: English
- Type: Thesis , Bachelor , BDiv
- Identifier: vital:1239 , http://hdl.handle.net/10962/d1007686 , Baptism in the Holy Spirit , Holy Spirit -- Biblical teaching
- Description: Conclusion: This study has helped us to perceive the significance of Christian Baptism as it arose from its antecedents, and yet differed decisively from them in meaning and significance. We have seen how Baptism grew from the New Testament situation into the life of the Early Church. We have considered the sacramental nature of Baptism, that here, while the Community is visibly active, in this holy sacrament, God is the doer of what is done. It is by Him, whose Grace is seen in Jesus Christ, that we are brought to new life within the Community of His Covenant and what He can do for adults, He can do for infants as well. However, it is good for us to remember that His presence is also for our judgement, and that there therefore remains upon us as individuals and as Community the requirement of faith and faithfulness. We have seen how it is that the Holy Spirit is given in Baptism, and we believe it is through His indwelling presence and power that we are able to come into the Family of God and enjoy that fellowship with Him, which is salvation. We have also seen that, despite many centuries of thought and study, no final doctrinal definition of Baptism is yet achieved, and that the Churches are still giving this serious attention.
- Full Text:
- Date Issued: 1974
Dialogues of sexualities: An action research project
- Authors: Graham, Nicola Susan Jearey
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3275 , http://hdl.handle.net/10962/d1021271
- Description: Risky and abusive sexual behaviours, stemming largely from inequitable gendered norms, are a pervasive feature of the South African socio-sexual landscape. Literature shows that sexuality education programmes can be effective in reducing risky sexual practices, but South African school sexuality education has been shown to be largely inadequate. The question arises as to how to engage with high school learners about sexualities in meaningful ways. In an attempt to answer this, I implemented a dialogical sexuality action research project at a lower middle class urban high school. Freirian principles of critical consciousness and dialogical pedagogy were utilized, and these were infused with feminist post-structural understandings of a discursively constituted subject. The initial consultative process started in 2012 with two projects at the school. Data from these projects, and a further consultation with the school principal, provided baseline information on the gendered norms and the sexuality education in the school. I then instituted a dialogical sexuality intervention with a group of Grade 10 learners, aiming to bring gendered and sexual norms to visibility, to trouble them (thereby promoting participants’ critical consciousness around gendered norms), and to provide recognition for participants in a variety of subject positions. Ten sessions were conducted, with the focus of each session being planned by the group. The action research project attempted to promote understandings of the processes required to facilitate such aims. The dialogical format of the group generated curiosity and engagement, and there were suggestions that some participants were taking up safe-sex messages in a reflexive manner. A partial normalisation of some ‘hidden’ aspects of sex, particularly around issues pertaining to female sexuality, was enabled, and critical consciousness around the gendered inequities in ‘cheating’ was promoted. However, abstinence was relatively silenced, and male same-sex remained heavily stigmatised. No substantial action component beyond the group meetings was generated. Participant feedback indicated that they placed great value on the dialogical processes in the group, and that they enjoyed being able to talk about sexual and other personal aspects of their lives. I theorise that the value of the group was in the recognition that participants received as they were positioned in a variety of subject positions. Whilst dialogue was shown to be extremely valuable, there were suggestions that other, non-dialogical modes of recognition were also needed by participants.
- Full Text:
- Date Issued: 2016
- Authors: Graham, Nicola Susan Jearey
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3275 , http://hdl.handle.net/10962/d1021271
- Description: Risky and abusive sexual behaviours, stemming largely from inequitable gendered norms, are a pervasive feature of the South African socio-sexual landscape. Literature shows that sexuality education programmes can be effective in reducing risky sexual practices, but South African school sexuality education has been shown to be largely inadequate. The question arises as to how to engage with high school learners about sexualities in meaningful ways. In an attempt to answer this, I implemented a dialogical sexuality action research project at a lower middle class urban high school. Freirian principles of critical consciousness and dialogical pedagogy were utilized, and these were infused with feminist post-structural understandings of a discursively constituted subject. The initial consultative process started in 2012 with two projects at the school. Data from these projects, and a further consultation with the school principal, provided baseline information on the gendered norms and the sexuality education in the school. I then instituted a dialogical sexuality intervention with a group of Grade 10 learners, aiming to bring gendered and sexual norms to visibility, to trouble them (thereby promoting participants’ critical consciousness around gendered norms), and to provide recognition for participants in a variety of subject positions. Ten sessions were conducted, with the focus of each session being planned by the group. The action research project attempted to promote understandings of the processes required to facilitate such aims. The dialogical format of the group generated curiosity and engagement, and there were suggestions that some participants were taking up safe-sex messages in a reflexive manner. A partial normalisation of some ‘hidden’ aspects of sex, particularly around issues pertaining to female sexuality, was enabled, and critical consciousness around the gendered inequities in ‘cheating’ was promoted. However, abstinence was relatively silenced, and male same-sex remained heavily stigmatised. No substantial action component beyond the group meetings was generated. Participant feedback indicated that they placed great value on the dialogical processes in the group, and that they enjoyed being able to talk about sexual and other personal aspects of their lives. I theorise that the value of the group was in the recognition that participants received as they were positioned in a variety of subject positions. Whilst dialogue was shown to be extremely valuable, there were suggestions that other, non-dialogical modes of recognition were also needed by participants.
- Full Text:
- Date Issued: 2016
Isolation, purification and effect of ligands on the nicotinic cholinergic receptor
- Authors: Kapp, Eugene Anthony
- Date: 1989
- Subjects: Ligands (Biochemistry) , Nicotinic receptors
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4550 , http://hdl.handle.net/10962/d1018235
- Description: The nicotinic cholinergic receptor protein of the fish electric organ, Torpedo fuscomaculata, has been isolated, purified and shown to represent a true model for the nAChR from other species and higher vertebrates. It is an integral membrane protein composed of four different subunits, tightly associated with other functional, but non-specific proteins. Purification of the nicotinic cholinergic receptor by chromatofocusing demonstrates an improved method over that of affinity and ion-exchange chromatography. Gel chromatography and SDS-polyacrylamide gel electrophoresis show evidence of four subunits; a(40-44 kDa), 6(53 kDa ),'Y(63 kDa) and 6(66 kDa) despite some degradation of receptor molecules by intracellular proteases. Spectrophotometric and fluorimetric studies of receptor-ligand interactions, show the functional and chemical integrity of the receptor to remain intact after solubilisation. The effect of cholinergic ligands on purified receptor preparations indicate quenching of the intrinsic fluorescence of the receptor. Agonists, like acetylcholine, bind and cause local conformational transitions, changing the active region from a hydrophobic to a hydrophilic environment. This phenomenon is illustrated by the 10-fold increase in fluorescence when the receptor is in a desensitised state. Antagonists, such as d-Tubocurarine, block this conformational transition. In vitro rectus abdominis muscle preparations . show the nitrosamines, dimethylnitrosamine and diphenylnitrosamine, to be true agonists of the nAChR. However their low affinity and specificity for the receptor precludes them as photoaffmity labelling agents. Photoactivation of dimethylnitrosamine occurs when associated with an acidic hydrogen at the active site of the receptor, suggesting energy-transfer labelling to be more facile than photoaffmity labelling. The membrane-bound receptor, in the presence of these nitrosamines, undergoes conformational transitions regulating the opening and closing of the ion-channel. Desensitisation and receptor activation are shown to involve one and the same molecular transition.
- Full Text:
- Date Issued: 1989
- Authors: Kapp, Eugene Anthony
- Date: 1989
- Subjects: Ligands (Biochemistry) , Nicotinic receptors
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4550 , http://hdl.handle.net/10962/d1018235
- Description: The nicotinic cholinergic receptor protein of the fish electric organ, Torpedo fuscomaculata, has been isolated, purified and shown to represent a true model for the nAChR from other species and higher vertebrates. It is an integral membrane protein composed of four different subunits, tightly associated with other functional, but non-specific proteins. Purification of the nicotinic cholinergic receptor by chromatofocusing demonstrates an improved method over that of affinity and ion-exchange chromatography. Gel chromatography and SDS-polyacrylamide gel electrophoresis show evidence of four subunits; a(40-44 kDa), 6(53 kDa ),'Y(63 kDa) and 6(66 kDa) despite some degradation of receptor molecules by intracellular proteases. Spectrophotometric and fluorimetric studies of receptor-ligand interactions, show the functional and chemical integrity of the receptor to remain intact after solubilisation. The effect of cholinergic ligands on purified receptor preparations indicate quenching of the intrinsic fluorescence of the receptor. Agonists, like acetylcholine, bind and cause local conformational transitions, changing the active region from a hydrophobic to a hydrophilic environment. This phenomenon is illustrated by the 10-fold increase in fluorescence when the receptor is in a desensitised state. Antagonists, such as d-Tubocurarine, block this conformational transition. In vitro rectus abdominis muscle preparations . show the nitrosamines, dimethylnitrosamine and diphenylnitrosamine, to be true agonists of the nAChR. However their low affinity and specificity for the receptor precludes them as photoaffmity labelling agents. Photoactivation of dimethylnitrosamine occurs when associated with an acidic hydrogen at the active site of the receptor, suggesting energy-transfer labelling to be more facile than photoaffmity labelling. The membrane-bound receptor, in the presence of these nitrosamines, undergoes conformational transitions regulating the opening and closing of the ion-channel. Desensitisation and receptor activation are shown to involve one and the same molecular transition.
- Full Text:
- Date Issued: 1989