Fluorescence “turn on” probe for bromide ion using nanoconjugates of glutathione-capped CdTe@ ZnS quantum dots with nickel tetraamino-phthalocyanine
- Adegoke, Oluwasesan, Nyokong, Tebello
- Authors: Adegoke, Oluwasesan , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190479 , vital:44998 , xlink:href="https://doi.org/10.1016/j.jphotochem.2013.05.013"
- Description: In this paper, three differently sized glutathione (GSH)-capped CdTe@ZnS quantum dots (QDs) have been successfully conjugated to nickel tetraamino-phthalocyanine (NiTAPc) to form different QDs-NiTAPc nanocomplexes. Several techniques such as TEM, FT-IR, time-resolved fluorescence measurement and electronic spectroscopy were employed to characterize the nanocomplex. Bromide ion was chosen as a model anion to test the efficacy of the nanoprobe. The fluorescence of the nanoconjugate was “turned off” upon binding but was progressively “turned on” upon interaction with varying concentrations of bromide ion. Experimental results showed that the quantum size effect of nanocrystal QD determined the overall sensitivity and selectivity of the nanoprobe and followed the order QD563-NiTAPc > QD605-NiTAPc > QD621-NiTAPc. The mechanism of reaction is proposed.
- Full Text:
- Date Issued: 2013
- Authors: Adegoke, Oluwasesan , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190479 , vital:44998 , xlink:href="https://doi.org/10.1016/j.jphotochem.2013.05.013"
- Description: In this paper, three differently sized glutathione (GSH)-capped CdTe@ZnS quantum dots (QDs) have been successfully conjugated to nickel tetraamino-phthalocyanine (NiTAPc) to form different QDs-NiTAPc nanocomplexes. Several techniques such as TEM, FT-IR, time-resolved fluorescence measurement and electronic spectroscopy were employed to characterize the nanocomplex. Bromide ion was chosen as a model anion to test the efficacy of the nanoprobe. The fluorescence of the nanoconjugate was “turned off” upon binding but was progressively “turned on” upon interaction with varying concentrations of bromide ion. Experimental results showed that the quantum size effect of nanocrystal QD determined the overall sensitivity and selectivity of the nanoprobe and followed the order QD563-NiTAPc > QD605-NiTAPc > QD621-NiTAPc. The mechanism of reaction is proposed.
- Full Text:
- Date Issued: 2013
For the people : an appraisal comparison of imagined communities in letters to two South African newspapers
- Authors: Smith, Jade
- Date: 2013
- Subjects: Daily Sun (Johannesburg, South Africa) , Times (Johannesburg, South Africa) , Mass media and social integration -- South Africa , Language and languages -- Usage , Mass media and language -- South Africa , Mass media and culture -- South Africa , Belonging (Social psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2385 , http://hdl.handle.net/10962/d1016264
- Description: This thesis reports on the bonds that unify imagined communities (Anderson 1983) that are created in 40 letters prominently displayed on the opinions pages of the Daily Sun, a popular tabloid, and The Times, a daily offshoot of the mainstream national Sunday Times. An APPRAISAL analysis of these letters reveals how the imagined communities attempt to align their audiences around distinctive couplings of interpersonal and ideational meaning. Such couplings represent the bonds around which community identities are co-constructed through affiliation and are evidence of the shared feelings that unite the communities of readership. Inferences drawn from this APPRAISAL information allow for a comparison of the natures of the two communities in terms of how they view their agency and group cohesion. Central to the analysis and interpretation of the data is the letters’ evaluative prosody, traced in order to determine the polarity of readers’ stances over four weeks. Asymmetrical prosodies are construed as pointing to the validity of ‘linguistic ventriloquism’, a term whose definition is refined and used as a diagnostic for whether the newspapers use their readers’ letters to promote their own stances on controversial matters. Principal findings show that both communities affiliate around the value of education, and dissatisfaction with the country’s political leaders, however The Times’ readers are more individualistic than the Daily Sun’s community members, who are concerned with the wellbeing of the group. The analysis highlights limitations to the application of the APPRAISAL framework, the value of subjectivity in the analytical process, and adds a new dimension to South African media studies, as it provides linguistic insights into the construction of imagined communities of newspaper readership.
- Full Text:
- Date Issued: 2013
- Authors: Smith, Jade
- Date: 2013
- Subjects: Daily Sun (Johannesburg, South Africa) , Times (Johannesburg, South Africa) , Mass media and social integration -- South Africa , Language and languages -- Usage , Mass media and language -- South Africa , Mass media and culture -- South Africa , Belonging (Social psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2385 , http://hdl.handle.net/10962/d1016264
- Description: This thesis reports on the bonds that unify imagined communities (Anderson 1983) that are created in 40 letters prominently displayed on the opinions pages of the Daily Sun, a popular tabloid, and The Times, a daily offshoot of the mainstream national Sunday Times. An APPRAISAL analysis of these letters reveals how the imagined communities attempt to align their audiences around distinctive couplings of interpersonal and ideational meaning. Such couplings represent the bonds around which community identities are co-constructed through affiliation and are evidence of the shared feelings that unite the communities of readership. Inferences drawn from this APPRAISAL information allow for a comparison of the natures of the two communities in terms of how they view their agency and group cohesion. Central to the analysis and interpretation of the data is the letters’ evaluative prosody, traced in order to determine the polarity of readers’ stances over four weeks. Asymmetrical prosodies are construed as pointing to the validity of ‘linguistic ventriloquism’, a term whose definition is refined and used as a diagnostic for whether the newspapers use their readers’ letters to promote their own stances on controversial matters. Principal findings show that both communities affiliate around the value of education, and dissatisfaction with the country’s political leaders, however The Times’ readers are more individualistic than the Daily Sun’s community members, who are concerned with the wellbeing of the group. The analysis highlights limitations to the application of the APPRAISAL framework, the value of subjectivity in the analytical process, and adds a new dimension to South African media studies, as it provides linguistic insights into the construction of imagined communities of newspaper readership.
- Full Text:
- Date Issued: 2013
Foraging ecology of Cape Gannets (Morus Capensis) at Bird Island, Algoa Bay
- Authors: Green, David Bruce
- Date: 2013
- Subjects: Birds of prey -- Behavior -- South Africa -- Algoa Bay , Gannets -- South Africa -- Algoa Bay , Birds -- Breeding -- South Africa -- Algoa Bay
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10725 , http://hdl.handle.net/10948/d1020790
- Description: The Cape gannet has undergone considerable population change and redistribution over the past 50 years. This has been linked to shifts in the abundance and distribution of their dominant prey, sardine and anchovy. Five breeding colonies, along the west coast of Southern Africa, have shown rapid population declines as a result of reduced prey availability. In contrast, a single colony (Bird Island, Algoa Bay) on the south coast of South Africa has, over the same period, grown fivefold and now supports approximately two thirds of the total population. Due to its conservation importance, and isolation from other breeding localities, it is important to assess the health of the Bird Island colony, and determine how foraging distribution relates to the environment to evaluate current measures of protection. This was achieved through two related studies; a long-term dietary analysis spanning 34 years, and a spatial foraging study, which related three years of tracking data to estimates of prey availability, oceanographic features and marine protected areas (MPAs). The results of the dietary study showed that the dietary constituents of Cape gannets breeding at Bird Island have remained similar over the last three decades, but the importance of sardine and anchovy has increased significantly. For sardine, in particular, this reflects an increased availability of this species (as deduced from hydroacoustic surveys) within the foraging range of the Bird Island colony. The dietary abundance of anchovy was found to be negatively correlated with that of sardine. Surprisingly,.the dietary abundance of anchovy was also negatively correlated with estimates of its availability based on acoustic surveys. The latter is likely to be due to sardine being a preferred prey item. Recent decreases in the dietary contribution of sardine (since 2005) suggest that this species is becoming less available to gannets, with profound implications in terms of nutrient gain associated with foraging. However, this has been mediated by an increase in the dietary contribution of anchovy, which now accounts for the vast majority of prey taken. Spatially, the foraging range of the Bird Island colony expanded during the three years of study, indicating an increase in effort. This increase was likely in an effort to track a distributional change of sardine and anchovy, which showed an apparent westward shift during the study period. There was, however, no evidence of birds tracking features associated with high productivity. This may have been partly due to anomalously warm conditions during the summer of 2012/2013, in which an absence of coastal upwelling prevented surface cooling. Nonetheless, low sea surface temperatures and high chlorophyll a concentrations do not seem to be reliable indicators of important Cape gannet foragingareas. Foraging effort was largely concentrated outside of MPAs, indicating that the current MPA network provides little protection for foraging gannets. This could change with the additional protection of the proposed Greater Addo Elephant National Park MPA expansion, as prey species are allowed to recover following the removal of fishing pressure. Overall, the colony appears to be in good condition as the diet is still dominated by live prey items, and the foraging range remains smaller than many of the colonies along the west coast. However, it is important that monitoring be continued, in particular with respect to changes in the availability of sardine and anchovy. Long-term shifts of these species out of the colony‘s foraging range could negatively influence the population in the future. This might be worsened by interspecific competition for prey resources. Considering the conservation importance of this population, maintenance of healthy prey stocks within the home range of breeding Cape gannets should be prioritised in order to prevent declines similar to those observed at west coast colonies.
- Full Text:
- Date Issued: 2013
- Authors: Green, David Bruce
- Date: 2013
- Subjects: Birds of prey -- Behavior -- South Africa -- Algoa Bay , Gannets -- South Africa -- Algoa Bay , Birds -- Breeding -- South Africa -- Algoa Bay
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10725 , http://hdl.handle.net/10948/d1020790
- Description: The Cape gannet has undergone considerable population change and redistribution over the past 50 years. This has been linked to shifts in the abundance and distribution of their dominant prey, sardine and anchovy. Five breeding colonies, along the west coast of Southern Africa, have shown rapid population declines as a result of reduced prey availability. In contrast, a single colony (Bird Island, Algoa Bay) on the south coast of South Africa has, over the same period, grown fivefold and now supports approximately two thirds of the total population. Due to its conservation importance, and isolation from other breeding localities, it is important to assess the health of the Bird Island colony, and determine how foraging distribution relates to the environment to evaluate current measures of protection. This was achieved through two related studies; a long-term dietary analysis spanning 34 years, and a spatial foraging study, which related three years of tracking data to estimates of prey availability, oceanographic features and marine protected areas (MPAs). The results of the dietary study showed that the dietary constituents of Cape gannets breeding at Bird Island have remained similar over the last three decades, but the importance of sardine and anchovy has increased significantly. For sardine, in particular, this reflects an increased availability of this species (as deduced from hydroacoustic surveys) within the foraging range of the Bird Island colony. The dietary abundance of anchovy was found to be negatively correlated with that of sardine. Surprisingly,.the dietary abundance of anchovy was also negatively correlated with estimates of its availability based on acoustic surveys. The latter is likely to be due to sardine being a preferred prey item. Recent decreases in the dietary contribution of sardine (since 2005) suggest that this species is becoming less available to gannets, with profound implications in terms of nutrient gain associated with foraging. However, this has been mediated by an increase in the dietary contribution of anchovy, which now accounts for the vast majority of prey taken. Spatially, the foraging range of the Bird Island colony expanded during the three years of study, indicating an increase in effort. This increase was likely in an effort to track a distributional change of sardine and anchovy, which showed an apparent westward shift during the study period. There was, however, no evidence of birds tracking features associated with high productivity. This may have been partly due to anomalously warm conditions during the summer of 2012/2013, in which an absence of coastal upwelling prevented surface cooling. Nonetheless, low sea surface temperatures and high chlorophyll a concentrations do not seem to be reliable indicators of important Cape gannet foragingareas. Foraging effort was largely concentrated outside of MPAs, indicating that the current MPA network provides little protection for foraging gannets. This could change with the additional protection of the proposed Greater Addo Elephant National Park MPA expansion, as prey species are allowed to recover following the removal of fishing pressure. Overall, the colony appears to be in good condition as the diet is still dominated by live prey items, and the foraging range remains smaller than many of the colonies along the west coast. However, it is important that monitoring be continued, in particular with respect to changes in the availability of sardine and anchovy. Long-term shifts of these species out of the colony‘s foraging range could negatively influence the population in the future. This might be worsened by interspecific competition for prey resources. Considering the conservation importance of this population, maintenance of healthy prey stocks within the home range of breeding Cape gannets should be prioritised in order to prevent declines similar to those observed at west coast colonies.
- Full Text:
- Date Issued: 2013
Forced degradation studies of clobetasol 17‐propionate in methanol, propylene glycol, as bulk drug and cream formulations by RP‐HPLC
- Fauzee, Ayesha F, Walker, Roderick B
- Authors: Fauzee, Ayesha F , Walker, Roderick B
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184005 , vital:44154 , xlink:href="https://doi.org/10.1002/jssc.201200969"
- Description: A rapid, simple, stability-indicating forced degradation study of clobetasol 17-propionate was conducted using RP-HPLC. The method was used to analyze clobetasol 17-propionate in methanol, propylene glycol, and a cream formulation. Isocratic elution of clobetasol and its degradation products was achieved using a Nova-Pak® 4 μm C18 150 mm × 3.9 mm id cartridge column and a mobile phase of methanol: water (68:32 v/v) at a flow rate of 0.9 mL min−1. Quantitation was achieved with UV detection at 239 nm. Nondegraded clobetasol was eluted at a retention time of 6.0 min. Clobetasol 17-propionate was subjected to different stress conditions viz., acidic, basic, heat, oxidation, light, and neutral hydrolysis. The greatest degradation occurred under strong base and oxidative conditions. Strong base-degraded clobetasol produced additional peaks at retention times of 1.8, 4.0, 5.0, and 8.0 min and clobetasol oxidation degradation peaks eluted at 2.2 and 24 min. Complete validation was performed for linearity, accuracy, and precision over the concentration range 0.15–15 μg mL−1. All data were analyzed statistically and this RP-HPLC method proved to be accurate, precise, linear, and stability indicating for the quantitation of clobetasol 17-propionate in methanol, propylene glycol, and cream formulations.
- Full Text:
- Date Issued: 2013
- Authors: Fauzee, Ayesha F , Walker, Roderick B
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184005 , vital:44154 , xlink:href="https://doi.org/10.1002/jssc.201200969"
- Description: A rapid, simple, stability-indicating forced degradation study of clobetasol 17-propionate was conducted using RP-HPLC. The method was used to analyze clobetasol 17-propionate in methanol, propylene glycol, and a cream formulation. Isocratic elution of clobetasol and its degradation products was achieved using a Nova-Pak® 4 μm C18 150 mm × 3.9 mm id cartridge column and a mobile phase of methanol: water (68:32 v/v) at a flow rate of 0.9 mL min−1. Quantitation was achieved with UV detection at 239 nm. Nondegraded clobetasol was eluted at a retention time of 6.0 min. Clobetasol 17-propionate was subjected to different stress conditions viz., acidic, basic, heat, oxidation, light, and neutral hydrolysis. The greatest degradation occurred under strong base and oxidative conditions. Strong base-degraded clobetasol produced additional peaks at retention times of 1.8, 4.0, 5.0, and 8.0 min and clobetasol oxidation degradation peaks eluted at 2.2 and 24 min. Complete validation was performed for linearity, accuracy, and precision over the concentration range 0.15–15 μg mL−1. All data were analyzed statistically and this RP-HPLC method proved to be accurate, precise, linear, and stability indicating for the quantitation of clobetasol 17-propionate in methanol, propylene glycol, and cream formulations.
- Full Text:
- Date Issued: 2013
Foreign direct investment and socio-economic development : the South African example
- Authors: Mukosera, Precious Sipho
- Date: 2013
- Subjects: Investments, Foreign -- South Africa , Investments, Foreign -- Government policy -- South Africa , South Africa -- Economic policy , South Africa -- Economic conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9142 , http://hdl.handle.net/10948/d1018760
- Description: It is widely accepted by governments of many developing countries that Foreign Direct Investment (FDI) is crucial to the socio-economic development of their nations and have developed various policies in an effort to attract FDI, as a result. FDI is a crucial source of technology, capital and skills for developing countries for economic growth that may ultimately lead to poverty reduction, employment creation and modernisation. However, results from many studies have been inconclusive and have failed to find a direct link between the increase of FDI and the associated socio-economic development of recipient nations. South Africa is no exception to this debate as it seeks to turn its back on decades long apartheid, which has entrenched poverty in the majority of its population and exacerbated social tensions. The main socio-economic challenges that South Africa faces include high unemployment, skills shortages, poverty and high inequality, and the 2008/2009 global financial and economic crisis has exacerbated the crisis. Despite these challenges South Africa‘s macro-economic strategies have had a good reputation since 2000. The monetary policy has turned out to be more transparent and predictable, and a sound fiscal policy has sustained its framework. The study analyses the role that FDI plays in the socio-economic development of South Africa since 1995 by focusing on selected case studies: ABSA Bank, General Motors South Africa (GMSA) and the Mining Sector of South Africa. The research concludes that although ABSA Bank has implemented several corporate social responsibility (CSR), and various employee development programmes, there is hardly any evidence to suggest that Barclays Bank‘s takeover of ABSA Bank has positively impacted on these programmes. General Motors South Africa (GMSA), which came into South Africa many decades ago through a Greenfield Investment, has played a positive role in the economy of the Eastern Cape Province as well as that of South Africa, having created jobs directly and indirectly. The company has also designed and implemented various educational, housing as well as health and awareness programmes for its employees and for the communities. Mining companies that operate in South Africa formed partnerships in the communities in which they operate in an effort to improve the lives of people. While these various projects have been a source of employment, they have had a limited impact on the core causes of social problems surrounding the mines. Many of these root causes relate to core business practices of the mining companies, especially employee recruitment, wages and housing. These root causes where witnessed in the Lonmin tragedy and in other strikes that spread throughout the sector in 2012. The study concludes that although FDI does play a role in the socio-economic development of South Africa, especially Greenfield investment, the same argument could not be made on Mergers and acquisitions (M&As). Finally, the South African government needs to play a proactive role in ensuring that foreign companies that invest in the country need to be well aware of the socio-economic needs of South Africa, and be willing to play a positive role in that regard.
- Full Text:
- Date Issued: 2013
- Authors: Mukosera, Precious Sipho
- Date: 2013
- Subjects: Investments, Foreign -- South Africa , Investments, Foreign -- Government policy -- South Africa , South Africa -- Economic policy , South Africa -- Economic conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9142 , http://hdl.handle.net/10948/d1018760
- Description: It is widely accepted by governments of many developing countries that Foreign Direct Investment (FDI) is crucial to the socio-economic development of their nations and have developed various policies in an effort to attract FDI, as a result. FDI is a crucial source of technology, capital and skills for developing countries for economic growth that may ultimately lead to poverty reduction, employment creation and modernisation. However, results from many studies have been inconclusive and have failed to find a direct link between the increase of FDI and the associated socio-economic development of recipient nations. South Africa is no exception to this debate as it seeks to turn its back on decades long apartheid, which has entrenched poverty in the majority of its population and exacerbated social tensions. The main socio-economic challenges that South Africa faces include high unemployment, skills shortages, poverty and high inequality, and the 2008/2009 global financial and economic crisis has exacerbated the crisis. Despite these challenges South Africa‘s macro-economic strategies have had a good reputation since 2000. The monetary policy has turned out to be more transparent and predictable, and a sound fiscal policy has sustained its framework. The study analyses the role that FDI plays in the socio-economic development of South Africa since 1995 by focusing on selected case studies: ABSA Bank, General Motors South Africa (GMSA) and the Mining Sector of South Africa. The research concludes that although ABSA Bank has implemented several corporate social responsibility (CSR), and various employee development programmes, there is hardly any evidence to suggest that Barclays Bank‘s takeover of ABSA Bank has positively impacted on these programmes. General Motors South Africa (GMSA), which came into South Africa many decades ago through a Greenfield Investment, has played a positive role in the economy of the Eastern Cape Province as well as that of South Africa, having created jobs directly and indirectly. The company has also designed and implemented various educational, housing as well as health and awareness programmes for its employees and for the communities. Mining companies that operate in South Africa formed partnerships in the communities in which they operate in an effort to improve the lives of people. While these various projects have been a source of employment, they have had a limited impact on the core causes of social problems surrounding the mines. Many of these root causes relate to core business practices of the mining companies, especially employee recruitment, wages and housing. These root causes where witnessed in the Lonmin tragedy and in other strikes that spread throughout the sector in 2012. The study concludes that although FDI does play a role in the socio-economic development of South Africa, especially Greenfield investment, the same argument could not be made on Mergers and acquisitions (M&As). Finally, the South African government needs to play a proactive role in ensuring that foreign companies that invest in the country need to be well aware of the socio-economic needs of South Africa, and be willing to play a positive role in that regard.
- Full Text:
- Date Issued: 2013
Forensic Entomology: An introduction, D.E. Gennard: book review
- Authors: Villet, Martin H
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451721 , vital:75072 , https://hdl.handle.net/10520/EJC141290
- Description: Dorothy Gennard's role in the fourth-year course in Forensic Science at the University of Lincoln has placed her in an excellent position to design a text that caters for this level. It was generally agreed (e.g. Villet and Richards 2008; Higley and Huntington 2009) that the first edition of her book, published in 2007, was a useful text for teaching introductory courses in forensics, and this substantially revised edition is even better suited to that niche. Other recently revised texts are either difficult to acquire (Haskell and Williams, 2008) or more expensive reference works (Amendt et al. 2010; Byrd and Castner 2010).
- Full Text:
- Date Issued: 2013
- Authors: Villet, Martin H
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451721 , vital:75072 , https://hdl.handle.net/10520/EJC141290
- Description: Dorothy Gennard's role in the fourth-year course in Forensic Science at the University of Lincoln has placed her in an excellent position to design a text that caters for this level. It was generally agreed (e.g. Villet and Richards 2008; Higley and Huntington 2009) that the first edition of her book, published in 2007, was a useful text for teaching introductory courses in forensics, and this substantially revised edition is even better suited to that niche. Other recently revised texts are either difficult to acquire (Haskell and Williams, 2008) or more expensive reference works (Amendt et al. 2010; Byrd and Castner 2010).
- Full Text:
- Date Issued: 2013
Form over function? The practical application of the Recognition of Customary Marriages Act 1998 in South Africa
- Authors: Kruuse, Helen
- Date: 2013
- Language: English
- Type: Article , text
- Identifier: http://hdl.handle.net/10962/54094 , vital:26389 , http://journals.co.za/content/ju_jur/2013/1/EJC148455
- Description: The Recognition of Customary Marriages Act 120 of 1998 is a major legislative measure for the development of customary marriages in line with the constitutional principle of equality, specifically for women. The article explores the interactions between this ideal in the Act with empirical observations and the latest judicial decisions concerning its application. It considers various examples of the lack of protection of women in relationships of a customary nature, and it concludes that both the state and courts favour a formal or definitional approach to customary marriage. In considering alternative approaches that could adequately protect vulnerable parties, two conclusions emerge: First, the article recommends a wholesale revision of the South African family law approach from a focus on form to dependency. Second (and as a short-term measure), the article advocates for the putative marriage doctrine to be applied in the customary marriage context to protect many women who are denied access to 'customary marriage' as a form, and as a result, all of the benefits that flow from such marriage.
- Full Text:
- Date Issued: 2013
- Authors: Kruuse, Helen
- Date: 2013
- Language: English
- Type: Article , text
- Identifier: http://hdl.handle.net/10962/54094 , vital:26389 , http://journals.co.za/content/ju_jur/2013/1/EJC148455
- Description: The Recognition of Customary Marriages Act 120 of 1998 is a major legislative measure for the development of customary marriages in line with the constitutional principle of equality, specifically for women. The article explores the interactions between this ideal in the Act with empirical observations and the latest judicial decisions concerning its application. It considers various examples of the lack of protection of women in relationships of a customary nature, and it concludes that both the state and courts favour a formal or definitional approach to customary marriage. In considering alternative approaches that could adequately protect vulnerable parties, two conclusions emerge: First, the article recommends a wholesale revision of the South African family law approach from a focus on form to dependency. Second (and as a short-term measure), the article advocates for the putative marriage doctrine to be applied in the customary marriage context to protect many women who are denied access to 'customary marriage' as a form, and as a result, all of the benefits that flow from such marriage.
- Full Text:
- Date Issued: 2013
From human to human(e): an educator's reflexive narrative journeying
- Authors: Rajoo, Neeranjini
- Date: 2013
- Subjects: Elementary school teachers -- South Africa , Poor -- South Africa , Humanity -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9588 , http://hdl.handle.net/10948/d1021001
- Description: From human to human(e) is an exploration of ways of coming to understand what it means to be(come) human and to belong (Vanier, 2003) while living and working as an educator in a disadvantaged community. In this sense, the purpose of this dissertation is the exploration of understanding what it might mean to be a ‘Foundation Phase’ (Primary/Elementary School) educator in a context of constructed poverty and disadvantage (Swanson 2004), thereby contributing to the field of education in this area, whilst embracing a practice of freedom and fostering apertures of hope and transcendence. This reflexive, rhizomatic narrative journeying (ibid) attempts to reach out to humanity via an interdisciplinary and arts-based approach that attempts to address concerns of inequity and pedagogical in-access and evokes the spiritual, emotive and philosophical in drawing attention to the ethical irresponsibility and socio-spiritual repercussions of ignoring social disadvantage in education. It includes inherences and impressions of humaneness in education. It seeks both introspection and insight into what ‘the human condition’ might mean to a just and robust education of children. In this sense, it is a personal inquiry as reflexive narrative journeying (ibid) based on twenty seven years of teaching in a primary school in a vulnerable and economically-impoverished community in the province of KwaZulu Natal in South Africa. As a writing-as-inquiry journeying, I engage with ‘critical rhizomatic narrative’ methodology (Swanson, 2004) as it resonates with the explorations of lived experiences that pertain to emotions, feelings, values and spirituality and because it enables a process of seeking what it might mean to be(come) human(e). This study is a philosophical rhizomatic narrative rendering which is an approach to(wards) understandings of personal growth and spirituality through understanding the various emergent journeys of life and the meanings that we can elicit from them to become more human and thus more humane.
- Full Text:
- Date Issued: 2013
- Authors: Rajoo, Neeranjini
- Date: 2013
- Subjects: Elementary school teachers -- South Africa , Poor -- South Africa , Humanity -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9588 , http://hdl.handle.net/10948/d1021001
- Description: From human to human(e) is an exploration of ways of coming to understand what it means to be(come) human and to belong (Vanier, 2003) while living and working as an educator in a disadvantaged community. In this sense, the purpose of this dissertation is the exploration of understanding what it might mean to be a ‘Foundation Phase’ (Primary/Elementary School) educator in a context of constructed poverty and disadvantage (Swanson 2004), thereby contributing to the field of education in this area, whilst embracing a practice of freedom and fostering apertures of hope and transcendence. This reflexive, rhizomatic narrative journeying (ibid) attempts to reach out to humanity via an interdisciplinary and arts-based approach that attempts to address concerns of inequity and pedagogical in-access and evokes the spiritual, emotive and philosophical in drawing attention to the ethical irresponsibility and socio-spiritual repercussions of ignoring social disadvantage in education. It includes inherences and impressions of humaneness in education. It seeks both introspection and insight into what ‘the human condition’ might mean to a just and robust education of children. In this sense, it is a personal inquiry as reflexive narrative journeying (ibid) based on twenty seven years of teaching in a primary school in a vulnerable and economically-impoverished community in the province of KwaZulu Natal in South Africa. As a writing-as-inquiry journeying, I engage with ‘critical rhizomatic narrative’ methodology (Swanson, 2004) as it resonates with the explorations of lived experiences that pertain to emotions, feelings, values and spirituality and because it enables a process of seeking what it might mean to be(come) human(e). This study is a philosophical rhizomatic narrative rendering which is an approach to(wards) understandings of personal growth and spirituality through understanding the various emergent journeys of life and the meanings that we can elicit from them to become more human and thus more humane.
- Full Text:
- Date Issued: 2013
From panic disorder to complex traumatic stress disorder : retrospective reflections on the case of Tariq
- Authors: Edwards, David J A
- Date: 2013
- Language: English
- Type: Article
- Identifier: vital:6234 , http://hdl.handle.net/10962/d1007784
- Description: This is a phenomenological-hermeneutic case study of Tariq who initially presented with panic disorder. It documents how, as therapy proceeded, the underlying meaning of his initial panic deepened as its roots in traumatic memories of childhood emerged. There were four spaced phases of treatment over four years. The first focused on anxiety management; the second was conceptualized within schema-focused therapy, and evoked and worked with childhood memories using inner child guided imagery; in the third and fourth phases insights gained led to an authentic re-engagement with family members in relationships that had been problematic. The panic attacks resolved and there were two dreams representing a reconfiguring of his relationship with his deceased father. The first two phases were the focus of an unpublished case study presented at a conference in 1995. This article incorporates material from that study and looks back at the case both in light of developments in phases two and three and also in light of theoretical developments in our understanding of complex trauma since the initial presentation.
- Full Text:
- Date Issued: 2013
- Authors: Edwards, David J A
- Date: 2013
- Language: English
- Type: Article
- Identifier: vital:6234 , http://hdl.handle.net/10962/d1007784
- Description: This is a phenomenological-hermeneutic case study of Tariq who initially presented with panic disorder. It documents how, as therapy proceeded, the underlying meaning of his initial panic deepened as its roots in traumatic memories of childhood emerged. There were four spaced phases of treatment over four years. The first focused on anxiety management; the second was conceptualized within schema-focused therapy, and evoked and worked with childhood memories using inner child guided imagery; in the third and fourth phases insights gained led to an authentic re-engagement with family members in relationships that had been problematic. The panic attacks resolved and there were two dreams representing a reconfiguring of his relationship with his deceased father. The first two phases were the focus of an unpublished case study presented at a conference in 1995. This article incorporates material from that study and looks back at the case both in light of developments in phases two and three and also in light of theoretical developments in our understanding of complex trauma since the initial presentation.
- Full Text:
- Date Issued: 2013
Functional changes of the vasculature in HIV/AIDS patients on Haart and Haart Naïve HIV participants
- Authors: Awotedu, Kofoworola Olajire
- Date: 2013
- Subjects: Cardiovascular system -- Diseases HIV infections -- Treatment
- Language: English
- Type: Thesis , Doctoral , Ph D
- Identifier: http://hdl.handle.net/11260/185 , vital:21366
- Description: The present study sought to explore the functional changes that occur in the vasculature of HIV positive participants of African origin in Mthatha district of South africa which might lead to increased risk in their cardiovascular system. Available literature shows that arterial stiffness plays an important role in cardiovascular events such as stroke, vasculitis and myocardial infarction. Measurement of (aortic pulse wave velocity; PWV) provides some of the strongest evidence concerning the prognostic significance of large artery stiffening. This study was aimed at investigating the relationship between anthropometry, age, E-Selectin level, cytokine levels, haemodynamic variables, blood counts and blood lipid profile with pulse wave velocity. Some traditional cardiovascular risk factors such as alcohol, and smoking were also taken into account. This was a cross-sectional study comprising of 169 participants (62 males and 107 females). 63 were HIV negative (group A), 54 HIV positive on treatment (group B), and 52 were HIV positive not on treatment (group C). Pulse wave velocity (PWV) was assessed using the Sphygmocor Vx. Statistically, ANOVA was used for variables with normal distribution and non parametric tests were used for variables with skewed distribution. Notable significant differences were seen in the means of the following variables across all the 3 groups. Conclusion: This study showed that HIV infected patients with or without antiretroviral therapy have increase arterial stiffness which is associated with an increased cardiovascular risk. The sphygmocor is an accurate, non invassive and useful tool in the evaluation of arterial stiffness and its use in clinical practice should be encouraged. PWV and the augmentation index (AIx) are the two major non- iv invasive methods of assessing arterial stiffness. Life style modification should be incorporated into the management of HIV patients so as the continuous monitoring of their haematological and lipid profile.
- Full Text:
- Date Issued: 2013
Functional changes of the vasculature in HIV/AIDS patients on Haart and Haart Naïve HIV participants
- Authors: Awotedu, Kofoworola Olajire
- Date: 2013
- Subjects: Cardiovascular system -- Diseases HIV infections -- Treatment
- Language: English
- Type: Thesis , Doctoral , Ph D
- Identifier: http://hdl.handle.net/11260/185 , vital:21366
- Description: The present study sought to explore the functional changes that occur in the vasculature of HIV positive participants of African origin in Mthatha district of South africa which might lead to increased risk in their cardiovascular system. Available literature shows that arterial stiffness plays an important role in cardiovascular events such as stroke, vasculitis and myocardial infarction. Measurement of (aortic pulse wave velocity; PWV) provides some of the strongest evidence concerning the prognostic significance of large artery stiffening. This study was aimed at investigating the relationship between anthropometry, age, E-Selectin level, cytokine levels, haemodynamic variables, blood counts and blood lipid profile with pulse wave velocity. Some traditional cardiovascular risk factors such as alcohol, and smoking were also taken into account. This was a cross-sectional study comprising of 169 participants (62 males and 107 females). 63 were HIV negative (group A), 54 HIV positive on treatment (group B), and 52 were HIV positive not on treatment (group C). Pulse wave velocity (PWV) was assessed using the Sphygmocor Vx. Statistically, ANOVA was used for variables with normal distribution and non parametric tests were used for variables with skewed distribution. Notable significant differences were seen in the means of the following variables across all the 3 groups. Conclusion: This study showed that HIV infected patients with or without antiretroviral therapy have increase arterial stiffness which is associated with an increased cardiovascular risk. The sphygmocor is an accurate, non invassive and useful tool in the evaluation of arterial stiffness and its use in clinical practice should be encouraged. PWV and the augmentation index (AIx) are the two major non- iv invasive methods of assessing arterial stiffness. Life style modification should be incorporated into the management of HIV patients so as the continuous monitoring of their haematological and lipid profile.
- Full Text:
- Date Issued: 2013
Gametogenesis, gonadal recrudescence, restraint and spawning patterns in Nile perch, Lates niloticus (Linnaeus, 1758)
- Authors: Kahwa, David
- Date: 2013
- Subjects: Nile perch -- Victoria, Lake Gametogenesis Oogenesis Spermatogenesis Nile perch -- Spawning -- Victoria, Lake Nile perch -- Induced spawning -- Victoria, Lake Nile perch -- Reproduction -- Endocrine aspects -- Victoria, Lake Fish culture -- Victoria, Lake
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5182 , http://hdl.handle.net/10962/d1001834
- Description: The Nile perch, Lates niloticus (Linnaeus, 1758), is a predacious freshwater fish widely distributed throughout the Afro-tropic eco-zone. The species was introduced to Lake Victoria in the early 1950s and by 1980 it had dominated the fisheries of Lake Victoria. This was followed by a dramatic decrease in the Nile perch fisheries production due to uncontrolled exploitation. The purpose of this thesis is to provide fundamental knowledge that can be applied in aquaculture and fisheries management through the study of the reproductive biology of L. niloticus. The research was aimed at the studying of the diverse aspects of the reproductive biology of L. niloticus in the Lake Victoria, Ugandan populations. This included reproductive patterns in relation to proximate environmental conditions, size at sexual maturity, gonad and gamete structure, gametogenesis and induced ovulation. The size at 50% sexual maturity for female Nile perch was 59.4 cm, which is lower than the earlier reported size of greater than 90 cm total length. Male L. niloticus matured at 57.8 cm total length in Lake Victoria. Microscopy revealed that L. niloticus from Lake Victoria had one spawning period that started in November and ended in March. Type I atresia occurred at high frequency from March to June, and type III atresia was present from July to September and between November and December. Spermatogenesis in L. niloticus is cystic and sperm development is the result of asynchronous activation of the germ cells. Type II spermatozoa are simple, uni-flagellate aquasperm with no acrosome. Oogenesis in L. niloticus differed from that of other fishes in that no cortical alveoli were present in any stage of oogenesis. Numerous oil globules were present in the primary yolk vesicle stage. This formed one centrally positioned, large oil globule in the tertiary yolk vesicle oocytes during final oocyte maturation. Clove oil was an effective sedative and an anaesthetic for the handling of L. niloticus. Induction time was more rapid at clove oil concentrations of 50 - 100 μl L⁻¹ than in fish exposed to clove oil concentrations less than 50 μl L⁻¹. Fish exposed to high concentrations exhibited significantly short induction times of less than 240 seconds. On average, fish recovered within 673 ± 58 seconds for all the concentrations used. Prolonged exposure of L. niloticus to low clove oil concentrations of 2.5 - 10 μl L⁻¹ did not change the blood plasma cortisol, glucose, and the lactate and chloride ion concentration, relative to the control treatment. Captive breeding was attempted by conducting induced spawning experiments. Only final oocyte maturation was achieved using a decapeptide Gonadotropin Releasing Hormone (Dargin, sGnRH-MET), combined with a water-soluble dopamine receptor antagonist metoclopramide. This thesis suggests a research approach that provides a basis for aquaculture of the new species by first studying reproductive biology patterns and then linking the information to gonad and gamete structure so that spawning times can be estimated. It further provides insights into aspects of the reproductive biology of the species and the effects of hormonal intervention on oocytes by showing at which stage of oocyte development hormones should be applied in L. niloticus. Clove oil can be used to sedate and anaesthetise L. niloticus broodfish to reduce the stress related to the handling of large specimens.
- Full Text:
- Date Issued: 2013
- Authors: Kahwa, David
- Date: 2013
- Subjects: Nile perch -- Victoria, Lake Gametogenesis Oogenesis Spermatogenesis Nile perch -- Spawning -- Victoria, Lake Nile perch -- Induced spawning -- Victoria, Lake Nile perch -- Reproduction -- Endocrine aspects -- Victoria, Lake Fish culture -- Victoria, Lake
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5182 , http://hdl.handle.net/10962/d1001834
- Description: The Nile perch, Lates niloticus (Linnaeus, 1758), is a predacious freshwater fish widely distributed throughout the Afro-tropic eco-zone. The species was introduced to Lake Victoria in the early 1950s and by 1980 it had dominated the fisheries of Lake Victoria. This was followed by a dramatic decrease in the Nile perch fisheries production due to uncontrolled exploitation. The purpose of this thesis is to provide fundamental knowledge that can be applied in aquaculture and fisheries management through the study of the reproductive biology of L. niloticus. The research was aimed at the studying of the diverse aspects of the reproductive biology of L. niloticus in the Lake Victoria, Ugandan populations. This included reproductive patterns in relation to proximate environmental conditions, size at sexual maturity, gonad and gamete structure, gametogenesis and induced ovulation. The size at 50% sexual maturity for female Nile perch was 59.4 cm, which is lower than the earlier reported size of greater than 90 cm total length. Male L. niloticus matured at 57.8 cm total length in Lake Victoria. Microscopy revealed that L. niloticus from Lake Victoria had one spawning period that started in November and ended in March. Type I atresia occurred at high frequency from March to June, and type III atresia was present from July to September and between November and December. Spermatogenesis in L. niloticus is cystic and sperm development is the result of asynchronous activation of the germ cells. Type II spermatozoa are simple, uni-flagellate aquasperm with no acrosome. Oogenesis in L. niloticus differed from that of other fishes in that no cortical alveoli were present in any stage of oogenesis. Numerous oil globules were present in the primary yolk vesicle stage. This formed one centrally positioned, large oil globule in the tertiary yolk vesicle oocytes during final oocyte maturation. Clove oil was an effective sedative and an anaesthetic for the handling of L. niloticus. Induction time was more rapid at clove oil concentrations of 50 - 100 μl L⁻¹ than in fish exposed to clove oil concentrations less than 50 μl L⁻¹. Fish exposed to high concentrations exhibited significantly short induction times of less than 240 seconds. On average, fish recovered within 673 ± 58 seconds for all the concentrations used. Prolonged exposure of L. niloticus to low clove oil concentrations of 2.5 - 10 μl L⁻¹ did not change the blood plasma cortisol, glucose, and the lactate and chloride ion concentration, relative to the control treatment. Captive breeding was attempted by conducting induced spawning experiments. Only final oocyte maturation was achieved using a decapeptide Gonadotropin Releasing Hormone (Dargin, sGnRH-MET), combined with a water-soluble dopamine receptor antagonist metoclopramide. This thesis suggests a research approach that provides a basis for aquaculture of the new species by first studying reproductive biology patterns and then linking the information to gonad and gamete structure so that spawning times can be estimated. It further provides insights into aspects of the reproductive biology of the species and the effects of hormonal intervention on oocytes by showing at which stage of oocyte development hormones should be applied in L. niloticus. Clove oil can be used to sedate and anaesthetise L. niloticus broodfish to reduce the stress related to the handling of large specimens.
- Full Text:
- Date Issued: 2013
Gasification characteristics of sugarcane bagasse
- Authors: Anukam, Anthony Ike
- Date: 2013
- Subjects: Bagasse -- Bagasse industry , Sugarcane -- Biotechnology , Computer simulation
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11343 , http://hdl.handle.net/10353/d1016170 , Bagasse -- Bagasse industry , Sugarcane -- Biotechnology , Computer simulation
- Description: Sugarcane is a major crop in many countries. It is the most abundant lignocellulosic material in tropical countries such as South Africa. It is one of the plants with the highest bioconversion efficiency. The sugarcane crop is able to efficiently fix solar energy, yielding some 55 tons of dry matter per hectare of land annually. After harvest, the crop produces sugar juice and bagasse. Sugarcane bagasse is a residue that results from the crushing of sugarcane in the sugar industry. It is a renewable feedstock that can be used for power generation and manufacturing cellulosic ethanol. As biomass, sugarcane bagasse holds promise as a fuel source since it can produce more than enough electricity and heat energy to supply the needs of a common sugar factory. However, in the sugarcane industry the bagasse is currently burnt inefficiently in boilers that provide the heating for the industry. This project seeks to investigate the possibility of gasifying sugarcane bagasse as an efficient conversion technology. The investigation is necessary because fuel properties govern the gasifier design and ultimately, the gasification efficiency. Proximate and ultimate analysis of sugarcane bagasse was conducted after which the results were used to conduct a computer simulation of the mass and energy balance during gasification. The kinetic investigation undertaken through the TGA and DTG analyses revealed the activation energy and pre – exponential factor which were obtained by the model – free Kissinger method of kinetic analysis and were found to be 181.51 kJ/mol and 3.1 × 103/min respectively. The heating value of sugarcane bagasse was also measured and found to be 17.8 MJ/kg, which was used in the calculation of the conversion efficiency of the gasification process. Fuel properties, including moisture content and gasifier operating parameters were varied in order to determine optimum gasifier operating conditions that results in maximum conversion efficiency. The highest conversion efficiency was achieved at low moisture content after computer simulation of the gasification process. Moisture content also affected the volume of CO and H2 as the former decreases with increasing moisture content while the latter increases with increasing moisture content, accelerating the water – gas reaction. Scanning electron microscope fitted to an Energy dispersive X – ray spectroscopy was also used in order to view the shape and size distribution as well as determine the elemental composition of sugarcane bagasse. The results obtained established that the fuel properties and gasification conditions affect the conversion efficiency. During computer simulation, it was established that smaller particle size resulted in higher conversion efficiency. The smaller throat diameter also resulted in higher conversion efficiency. The throat angle of 25° also resulted in higher conversion efficiency. The temperature of input air was also found to be one of the major determining factors in terms of conversion efficiency. The dissertation presents the proximate and ultimate analysis results as well as the kinetic analysis results. The SEM/EDX analysis as well as the computer simulation results of the gasification process is also presented. The major contribution of this project was on the investigation of the gasification characteristics of sugarcane bagasse and the utilization of these in the design of a laboratory scale sugarcane bagasse gasifier with enhanced conversion efficiency through computer simulation.
- Full Text:
- Date Issued: 2013
- Authors: Anukam, Anthony Ike
- Date: 2013
- Subjects: Bagasse -- Bagasse industry , Sugarcane -- Biotechnology , Computer simulation
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11343 , http://hdl.handle.net/10353/d1016170 , Bagasse -- Bagasse industry , Sugarcane -- Biotechnology , Computer simulation
- Description: Sugarcane is a major crop in many countries. It is the most abundant lignocellulosic material in tropical countries such as South Africa. It is one of the plants with the highest bioconversion efficiency. The sugarcane crop is able to efficiently fix solar energy, yielding some 55 tons of dry matter per hectare of land annually. After harvest, the crop produces sugar juice and bagasse. Sugarcane bagasse is a residue that results from the crushing of sugarcane in the sugar industry. It is a renewable feedstock that can be used for power generation and manufacturing cellulosic ethanol. As biomass, sugarcane bagasse holds promise as a fuel source since it can produce more than enough electricity and heat energy to supply the needs of a common sugar factory. However, in the sugarcane industry the bagasse is currently burnt inefficiently in boilers that provide the heating for the industry. This project seeks to investigate the possibility of gasifying sugarcane bagasse as an efficient conversion technology. The investigation is necessary because fuel properties govern the gasifier design and ultimately, the gasification efficiency. Proximate and ultimate analysis of sugarcane bagasse was conducted after which the results were used to conduct a computer simulation of the mass and energy balance during gasification. The kinetic investigation undertaken through the TGA and DTG analyses revealed the activation energy and pre – exponential factor which were obtained by the model – free Kissinger method of kinetic analysis and were found to be 181.51 kJ/mol and 3.1 × 103/min respectively. The heating value of sugarcane bagasse was also measured and found to be 17.8 MJ/kg, which was used in the calculation of the conversion efficiency of the gasification process. Fuel properties, including moisture content and gasifier operating parameters were varied in order to determine optimum gasifier operating conditions that results in maximum conversion efficiency. The highest conversion efficiency was achieved at low moisture content after computer simulation of the gasification process. Moisture content also affected the volume of CO and H2 as the former decreases with increasing moisture content while the latter increases with increasing moisture content, accelerating the water – gas reaction. Scanning electron microscope fitted to an Energy dispersive X – ray spectroscopy was also used in order to view the shape and size distribution as well as determine the elemental composition of sugarcane bagasse. The results obtained established that the fuel properties and gasification conditions affect the conversion efficiency. During computer simulation, it was established that smaller particle size resulted in higher conversion efficiency. The smaller throat diameter also resulted in higher conversion efficiency. The throat angle of 25° also resulted in higher conversion efficiency. The temperature of input air was also found to be one of the major determining factors in terms of conversion efficiency. The dissertation presents the proximate and ultimate analysis results as well as the kinetic analysis results. The SEM/EDX analysis as well as the computer simulation results of the gasification process is also presented. The major contribution of this project was on the investigation of the gasification characteristics of sugarcane bagasse and the utilization of these in the design of a laboratory scale sugarcane bagasse gasifier with enhanced conversion efficiency through computer simulation.
- Full Text:
- Date Issued: 2013
Gaze behaviour of volleyball players during successful serve reception
- Authors: Ramphomane-Aandahl, Bonolo
- Date: 2013
- Subjects: Gaze -- Psychological aspects , Visual perception , Volleyball players
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10113 , http://hdl.handle.net/10948/d1021007
- Description: The aim of this study was to identify and compare the gaze behaviour of both advancement levels (Advanced and Not Advanced) and genders (female and male) during successful serve reception. A quantitative, exploratory and quasi-experimental research design was used in which 50 ToppVolley Norway student athletes aged 16 to 19 years were sampled. The gaze behaviour of junior volleyball athletes was assesed as they received two types of serves (1 float and 1 top spin jump serve) and performed a forearm and/or overhead pass to a setter’s target while wearing an ASL mobile eye tracker. Gaze characteristics such as fixation number, fixation duration and areas of interest were used to achieve the aim of the study. The study found that Advanced participants differed from the Not Advanced athletes in employing fewer (9.70 ± 1.14 versus 10.77 ± 3.63 , p<.05, d>.20 ) fixations but for longer durations per fixations (1.64 ± 0.20 versus 1.60 ± 0.34, p<.05, d>.20 ) in receiving the float serve. Contrary, for the reception of the top spin jump serve, the Advanced athletes employed more fixations (12.11 ± 2.40 versus 11.83 ± 2.17, p<.05, d>.20 ) but for shorter durations per fixations (1.57 ± 0.26 versus 1.65 ± 0.34 sec, p<.05, d>.20 ) than the Not Advanced athletes. Male athletes in this study were more experienced than their female counterparts (5.97 ± 1.62 years versus 4.75 ± 1.59 years, p<.05, d>.20 ) with males employing more fixations than the females (11.02 ± 3.63 versus 9.19 ± 1.55 and 12.26 ± 2.46 versus 11.36 ± 1.69, p<.05, d>.20 ) for the float and top spin serves respectively but for shorter durations per fixation (1.62 ± 0.27 versus 1.76 ± 0.29 sec (float) and 1.56 ± 0.32 versus 1.73 ± 0.28 sec (top spin) p<.05, d>.20 ) than the female athletes. These results and findings suggests that Advanced athletes for both serves attended to the most appropriate visual information through the top-down approach, their knowledge and past experiences. For gender differences, the results show that the female athletes employed fewer fixation points in receiving float serves, however the employment of fewer fixation points during the top spin jump serves was due to receiving serves characterised by easily identifiable trajectories and lower speeds. The contradicting finding of the Advanced athletes employing more fixation points for the top spin jump serve may be due to task complexity demands. Thirteen areas of interests were also identified. The combined results for both gender and advancement levels suggest that the athletes fixated on similar areas of interests, primarily the upper body and secondary on the ball (flight), serve reception phase, arrival at target and contact point. The aim and objectives of this study were achieved in that both absolute and relative values for number of fixations, duration of fixations and areas of interest fixated on, were established. However the outcome of comparisons made, were not all expected particularly that of the Advanced group for the top spin jump serve. Possible explanations were offered, but further research is required in this regard.
- Full Text:
- Date Issued: 2013
- Authors: Ramphomane-Aandahl, Bonolo
- Date: 2013
- Subjects: Gaze -- Psychological aspects , Visual perception , Volleyball players
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10113 , http://hdl.handle.net/10948/d1021007
- Description: The aim of this study was to identify and compare the gaze behaviour of both advancement levels (Advanced and Not Advanced) and genders (female and male) during successful serve reception. A quantitative, exploratory and quasi-experimental research design was used in which 50 ToppVolley Norway student athletes aged 16 to 19 years were sampled. The gaze behaviour of junior volleyball athletes was assesed as they received two types of serves (1 float and 1 top spin jump serve) and performed a forearm and/or overhead pass to a setter’s target while wearing an ASL mobile eye tracker. Gaze characteristics such as fixation number, fixation duration and areas of interest were used to achieve the aim of the study. The study found that Advanced participants differed from the Not Advanced athletes in employing fewer (9.70 ± 1.14 versus 10.77 ± 3.63 , p<.05, d>.20 ) fixations but for longer durations per fixations (1.64 ± 0.20 versus 1.60 ± 0.34, p<.05, d>.20 ) in receiving the float serve. Contrary, for the reception of the top spin jump serve, the Advanced athletes employed more fixations (12.11 ± 2.40 versus 11.83 ± 2.17, p<.05, d>.20 ) but for shorter durations per fixations (1.57 ± 0.26 versus 1.65 ± 0.34 sec, p<.05, d>.20 ) than the Not Advanced athletes. Male athletes in this study were more experienced than their female counterparts (5.97 ± 1.62 years versus 4.75 ± 1.59 years, p<.05, d>.20 ) with males employing more fixations than the females (11.02 ± 3.63 versus 9.19 ± 1.55 and 12.26 ± 2.46 versus 11.36 ± 1.69, p<.05, d>.20 ) for the float and top spin serves respectively but for shorter durations per fixation (1.62 ± 0.27 versus 1.76 ± 0.29 sec (float) and 1.56 ± 0.32 versus 1.73 ± 0.28 sec (top spin) p<.05, d>.20 ) than the female athletes. These results and findings suggests that Advanced athletes for both serves attended to the most appropriate visual information through the top-down approach, their knowledge and past experiences. For gender differences, the results show that the female athletes employed fewer fixation points in receiving float serves, however the employment of fewer fixation points during the top spin jump serves was due to receiving serves characterised by easily identifiable trajectories and lower speeds. The contradicting finding of the Advanced athletes employing more fixation points for the top spin jump serve may be due to task complexity demands. Thirteen areas of interests were also identified. The combined results for both gender and advancement levels suggest that the athletes fixated on similar areas of interests, primarily the upper body and secondary on the ball (flight), serve reception phase, arrival at target and contact point. The aim and objectives of this study were achieved in that both absolute and relative values for number of fixations, duration of fixations and areas of interest fixated on, were established. However the outcome of comparisons made, were not all expected particularly that of the Advanced group for the top spin jump serve. Possible explanations were offered, but further research is required in this regard.
- Full Text:
- Date Issued: 2013
Gazing at Exhibit A
- Authors: Krueger, Anton
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/229643 , vital:49696 , xlink:href="http://liminalities.net/9-1/exhibit.pdf"
- Description: Brett Bailey recently toured a new work in Europe and South Africa, called The Exhibit Series (2010-2013). In different countries the work has appeared under different titles—Exhibit A and Exhibit B, while Exhibit C will be produced in 2014. These productions replicate and parody ethnographic spectacles of the nineteenth century, interrogating European colonial atrocities in Africa, as well as contemporary xenophobia. They consist of a series of installations housed in individual rooms that audience members enter one by one. Inside these rooms one is confronted by beautifully arranged spectacles referencing historical atrocities committed in Namibia by German speaking peoples, as well as atrocities under the Belgian and French colonial regimes in the two Congos. The “exhibits” also include references to more recent incidents of European racism against migrants from Africa. The work has been both applauded and derided. In Berlin, for example, activists called it “a human zoo” and protested that this was “the wrong way to discuss a violent colonial history,”1 while others have called the work “haunting”, praising the production for its “dignity” and “beauty.”2
- Full Text:
- Date Issued: 2013
- Authors: Krueger, Anton
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/229643 , vital:49696 , xlink:href="http://liminalities.net/9-1/exhibit.pdf"
- Description: Brett Bailey recently toured a new work in Europe and South Africa, called The Exhibit Series (2010-2013). In different countries the work has appeared under different titles—Exhibit A and Exhibit B, while Exhibit C will be produced in 2014. These productions replicate and parody ethnographic spectacles of the nineteenth century, interrogating European colonial atrocities in Africa, as well as contemporary xenophobia. They consist of a series of installations housed in individual rooms that audience members enter one by one. Inside these rooms one is confronted by beautifully arranged spectacles referencing historical atrocities committed in Namibia by German speaking peoples, as well as atrocities under the Belgian and French colonial regimes in the two Congos. The “exhibits” also include references to more recent incidents of European racism against migrants from Africa. The work has been both applauded and derided. In Berlin, for example, activists called it “a human zoo” and protested that this was “the wrong way to discuss a violent colonial history,”1 while others have called the work “haunting”, praising the production for its “dignity” and “beauty.”2
- Full Text:
- Date Issued: 2013
GDR development policy with special reference to Africa, c. 1960-1990
- Van der Heyden, Ulrich Klaus Helmut
- Authors: Van der Heyden, Ulrich Klaus Helmut
- Date: 2013
- Subjects: Germany -- Foreign relations -- Africa , Germany -- Foreign economic relations -- Africa , Africa -- Foreign relations -- Germany , Africa -- Foreign economic relations -- Germany , Africa -- Politics and government -- 1960- , Africa -- History -- 1960-
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2531 , http://hdl.handle.net/10962/d1001860
- Description: This thesis explores the political, economic and theoretical underpinnings of the German Democratic Republic’s (GDR’s) development policies towards the Third World between c.1960 and 1990. Particular attention is paid to Africa. Case studies of assistance to SWAPO and the ANC further focus the attention of the reader on southern Africa in particular. Aspects of both military and civilian aid are considered, including both development initiatives overseas in Africa, and development training for Africans within the GDR itself. Since German “reunification”, the GDR’s history has been explored largely from a West German perspective. The present work attempts to provide a more balanced view of successes and shortcomings of the GDR’s policies towards, and interaction with, African countries and liberation movements. It also aims to bring to the attention of English-speaking readers German archival sources, other primary sources and published works which they would otherwise have been unlikely to encounter. From its formation, the GDR made strenuous efforts to develop relations with countries which were either free from colonial dependency or were struggling for freedom. Over the course of thirty years, it followed a number of different approaches, and developed diverse objectives. These were shaped in the wider context of the cold war, the Hallstein doctrine (which established that the FRG – and, in effect, its allies - would not establish or maintain diplomatic relations with any state that recognised the GDR), the relationships between the GDR and partner socialist states, and the economic difficulties faced by the GDR. Arising from this complex situation, from time to time, both internally in the GDR and in terms of its foreign affairs, tensions and discrepancies arose between theoretical objectives and political and economic reality. Despite these severe constraints, during the period under review, the volume and range of the GDR’s relationships with developing countries increased dramatically. For example, between 1970 and 1987, the number of developing countries with which the GDR had foreign economic relations on the basis of international agreements grew from 23 to 64. Viewed within its economic context, the state was arguably far more committed to development aid than the Federal Republic of Germany. In addition, there is a great deal of evidence that “solidarity” with developing nations and the oppressed enjoyed a considerable degree of popular support.
- Full Text:
- Date Issued: 2013
- Authors: Van der Heyden, Ulrich Klaus Helmut
- Date: 2013
- Subjects: Germany -- Foreign relations -- Africa , Germany -- Foreign economic relations -- Africa , Africa -- Foreign relations -- Germany , Africa -- Foreign economic relations -- Germany , Africa -- Politics and government -- 1960- , Africa -- History -- 1960-
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2531 , http://hdl.handle.net/10962/d1001860
- Description: This thesis explores the political, economic and theoretical underpinnings of the German Democratic Republic’s (GDR’s) development policies towards the Third World between c.1960 and 1990. Particular attention is paid to Africa. Case studies of assistance to SWAPO and the ANC further focus the attention of the reader on southern Africa in particular. Aspects of both military and civilian aid are considered, including both development initiatives overseas in Africa, and development training for Africans within the GDR itself. Since German “reunification”, the GDR’s history has been explored largely from a West German perspective. The present work attempts to provide a more balanced view of successes and shortcomings of the GDR’s policies towards, and interaction with, African countries and liberation movements. It also aims to bring to the attention of English-speaking readers German archival sources, other primary sources and published works which they would otherwise have been unlikely to encounter. From its formation, the GDR made strenuous efforts to develop relations with countries which were either free from colonial dependency or were struggling for freedom. Over the course of thirty years, it followed a number of different approaches, and developed diverse objectives. These were shaped in the wider context of the cold war, the Hallstein doctrine (which established that the FRG – and, in effect, its allies - would not establish or maintain diplomatic relations with any state that recognised the GDR), the relationships between the GDR and partner socialist states, and the economic difficulties faced by the GDR. Arising from this complex situation, from time to time, both internally in the GDR and in terms of its foreign affairs, tensions and discrepancies arose between theoretical objectives and political and economic reality. Despite these severe constraints, during the period under review, the volume and range of the GDR’s relationships with developing countries increased dramatically. For example, between 1970 and 1987, the number of developing countries with which the GDR had foreign economic relations on the basis of international agreements grew from 23 to 64. Viewed within its economic context, the state was arguably far more committed to development aid than the Federal Republic of Germany. In addition, there is a great deal of evidence that “solidarity” with developing nations and the oppressed enjoyed a considerable degree of popular support.
- Full Text:
- Date Issued: 2013
Gender and age differences between managers and employees on organisational commitment in selected factories in the Buffalo City Metropolitan area
- Authors: Qwabe, Nombali Palesa
- Date: 2013
- Subjects: Employee loyalty -- South Africa -- Eastern Cape , Organizational commitment -- South Africa -- Eastern Cape , Sex discrimination -- South Africa -- Eastern Cape , Executives -- South Africa -- Eastern Cape , Employee morale -- South Africa -- Eastern Cape , Employee motivation -- South Africa -- Eastern Cape , Employee retention -- South Africa -- Eastern Cape , Labor turnover -- South Africa -- Eastern Cape , Organisational commitment , Affective commitment , Continuance commitment , Normative commitment , Gender differences , Age differences
- Language: English
- Type: Thesis , Masters , MCom (Industrial Psychology)
- Identifier: vital:11557 , http://hdl.handle.net/10353/d1007117 , Employee loyalty -- South Africa -- Eastern Cape , Organizational commitment -- South Africa -- Eastern Cape , Sex discrimination -- South Africa -- Eastern Cape , Executives -- South Africa -- Eastern Cape , Employee morale -- South Africa -- Eastern Cape , Employee motivation -- South Africa -- Eastern Cape , Employee retention -- South Africa -- Eastern Cape , Labor turnover -- South Africa -- Eastern Cape , Organisational commitment , Affective commitment , Continuance commitment , Normative commitment , Gender differences , Age differences
- Description: Employee commitment is one of the most important aspects that help an organisation achieve its desired goals. This study investigates the possible effects of gender and age differences between managers and employees on organisational commitment among lower-level employees in selected factories in the Buffalo City Metropolitan area. The organisational commitment instrument used in this research is the Meyer and Allen (1997) organisational commitment questionnaire which contains 18 items (6 items for each scale: affective commitment, continuance commitment and normative commitment). For this purpose, a sample of 100 lower-level employees was used. The results indicated significant differences in the unexpected directions in affective commitment and continuance commitment between male employees supervised by male managers and male employees supervised by female managers; male employees were found to have higher levels of affective and continuance commitment when supervised by female managers. Female employees were found to have a higher level of normative commitment when supervised by male managers than when supervised by female managers which was also in the unexpected direction. In addition, the study showed surprising results in terms of the social or cultural hypothesis where employees supervised by male managers and older managers were not significantly different in organisational commitment to those managed by female and by younger or same-age managers.
- Full Text:
- Date Issued: 2013
- Authors: Qwabe, Nombali Palesa
- Date: 2013
- Subjects: Employee loyalty -- South Africa -- Eastern Cape , Organizational commitment -- South Africa -- Eastern Cape , Sex discrimination -- South Africa -- Eastern Cape , Executives -- South Africa -- Eastern Cape , Employee morale -- South Africa -- Eastern Cape , Employee motivation -- South Africa -- Eastern Cape , Employee retention -- South Africa -- Eastern Cape , Labor turnover -- South Africa -- Eastern Cape , Organisational commitment , Affective commitment , Continuance commitment , Normative commitment , Gender differences , Age differences
- Language: English
- Type: Thesis , Masters , MCom (Industrial Psychology)
- Identifier: vital:11557 , http://hdl.handle.net/10353/d1007117 , Employee loyalty -- South Africa -- Eastern Cape , Organizational commitment -- South Africa -- Eastern Cape , Sex discrimination -- South Africa -- Eastern Cape , Executives -- South Africa -- Eastern Cape , Employee morale -- South Africa -- Eastern Cape , Employee motivation -- South Africa -- Eastern Cape , Employee retention -- South Africa -- Eastern Cape , Labor turnover -- South Africa -- Eastern Cape , Organisational commitment , Affective commitment , Continuance commitment , Normative commitment , Gender differences , Age differences
- Description: Employee commitment is one of the most important aspects that help an organisation achieve its desired goals. This study investigates the possible effects of gender and age differences between managers and employees on organisational commitment among lower-level employees in selected factories in the Buffalo City Metropolitan area. The organisational commitment instrument used in this research is the Meyer and Allen (1997) organisational commitment questionnaire which contains 18 items (6 items for each scale: affective commitment, continuance commitment and normative commitment). For this purpose, a sample of 100 lower-level employees was used. The results indicated significant differences in the unexpected directions in affective commitment and continuance commitment between male employees supervised by male managers and male employees supervised by female managers; male employees were found to have higher levels of affective and continuance commitment when supervised by female managers. Female employees were found to have a higher level of normative commitment when supervised by male managers than when supervised by female managers which was also in the unexpected direction. In addition, the study showed surprising results in terms of the social or cultural hypothesis where employees supervised by male managers and older managers were not significantly different in organisational commitment to those managed by female and by younger or same-age managers.
- Full Text:
- Date Issued: 2013
Gender equality in the employment of senior secondary schools managers in the district of Butterworth
- Authors: Bikitsha, Sakhiwo
- Date: 2013
- Subjects: Educational equalization -- South Africa -- Eastern Cape , Sex discrimination in education -- South Africa -- Eastern Cape , School management and organization
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8489 , http://hdl.handle.net/10948/d1020005
- Description: In terms of Section 9 of the Constitution of the Republic of South Africa of 1996, Chapter Two, the Bill of Rights, there should be gender equality amongst other things. In terms of Section15 (i) of the Employment Equity Act (Act 55 of 1998), there should be equal representation of suitably qualified people from the designated groups (blacks, women and people with disabilities) in all occupational categories and levels in the workforce. Section 15 (ii)provides that an employer who employs more than 50 employees must conduct a gender audit and make a gender equity plan and implement it when new employees are employed. In the Department of Education in the District of Butterworth, there is no gender equality in the number of senior secondary school managers. Men constituted 65 percent and women constituted 35 percent. The study investigated reasons for unequal representation of men and women as senior secondary school managers. The study was qualitative in design. The participants in the study were the Assistant Director of the Human Resource Section of the Department of Education and school governing body members, who were parents and educators. Interviews were used to collect data from the participants The study found that, amongst other things, gender equity was not considered when senior secondary schools managers were employed. That was why there was unequal representation of men and women in senior secondary schools’ management positions. This implied that those involved in the employment of secondary school managers in the district of Butterworth did not consider the Employment Equity Act (Act 55 of 1998) as a guide when employing senior secondary school managers in order to be able to achieve gender equality in this position. That was why there was unequal representation of men and women in senior secondary schools’ management positions.
- Full Text:
- Date Issued: 2013
- Authors: Bikitsha, Sakhiwo
- Date: 2013
- Subjects: Educational equalization -- South Africa -- Eastern Cape , Sex discrimination in education -- South Africa -- Eastern Cape , School management and organization
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8489 , http://hdl.handle.net/10948/d1020005
- Description: In terms of Section 9 of the Constitution of the Republic of South Africa of 1996, Chapter Two, the Bill of Rights, there should be gender equality amongst other things. In terms of Section15 (i) of the Employment Equity Act (Act 55 of 1998), there should be equal representation of suitably qualified people from the designated groups (blacks, women and people with disabilities) in all occupational categories and levels in the workforce. Section 15 (ii)provides that an employer who employs more than 50 employees must conduct a gender audit and make a gender equity plan and implement it when new employees are employed. In the Department of Education in the District of Butterworth, there is no gender equality in the number of senior secondary school managers. Men constituted 65 percent and women constituted 35 percent. The study investigated reasons for unequal representation of men and women as senior secondary school managers. The study was qualitative in design. The participants in the study were the Assistant Director of the Human Resource Section of the Department of Education and school governing body members, who were parents and educators. Interviews were used to collect data from the participants The study found that, amongst other things, gender equity was not considered when senior secondary schools managers were employed. That was why there was unequal representation of men and women in senior secondary schools’ management positions. This implied that those involved in the employment of secondary school managers in the district of Butterworth did not consider the Employment Equity Act (Act 55 of 1998) as a guide when employing senior secondary school managers in order to be able to achieve gender equality in this position. That was why there was unequal representation of men and women in senior secondary schools’ management positions.
- Full Text:
- Date Issued: 2013
Gendered roles and social behaviour towards women in marginalised communities: the case of Newlands location in East London
- Authors: Jilingisi, Ntombodidi
- Date: 2013
- Subjects: Equality -- South Africa -- East London , Sex discrimination against women -- South Africa -- East London , Interpersonal relations -- South Africa -- East London
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9163 , http://hdl.handle.net/10948/d1020038
- Description: This research study aims to investigate the impact of gender roles and social behaviour towards women in marginalised communities in Newlands Location. The researcher used a qualitative research method to conduct the study through interviews. The study has five chapters: Chapter 1 focuses on the introduction and the background of the study; Chapter 2 is the literature review, where it clarifies the meaning of gender inequality and discusses gender inequality in education, economic growth and violence against women; Chapter 3 is the description of the methods used in assessing the impact of gender inequality in Newlands Location and outlines the processes followed in the study'; Chapter 4 are the findings and the achievements of aim and objectives of the study; Lastly, Chapter 5 focuses on the Conclusion, Limitations and Recommendations of the study. Newlands location need a serious intermediation to address the gender inequality issues.
- Full Text:
- Date Issued: 2013
- Authors: Jilingisi, Ntombodidi
- Date: 2013
- Subjects: Equality -- South Africa -- East London , Sex discrimination against women -- South Africa -- East London , Interpersonal relations -- South Africa -- East London
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9163 , http://hdl.handle.net/10948/d1020038
- Description: This research study aims to investigate the impact of gender roles and social behaviour towards women in marginalised communities in Newlands Location. The researcher used a qualitative research method to conduct the study through interviews. The study has five chapters: Chapter 1 focuses on the introduction and the background of the study; Chapter 2 is the literature review, where it clarifies the meaning of gender inequality and discusses gender inequality in education, economic growth and violence against women; Chapter 3 is the description of the methods used in assessing the impact of gender inequality in Newlands Location and outlines the processes followed in the study'; Chapter 4 are the findings and the achievements of aim and objectives of the study; Lastly, Chapter 5 focuses on the Conclusion, Limitations and Recommendations of the study. Newlands location need a serious intermediation to address the gender inequality issues.
- Full Text:
- Date Issued: 2013
Genetic approaches to improve salinity tolerance in plants
- Kumar, Ashwani, Gupta, Aditi, Azooz, M M, Sharma, S, Ahmad, Parvaiz, Dames, Joanna F
- Authors: Kumar, Ashwani , Gupta, Aditi , Azooz, M M , Sharma, S , Ahmad, Parvaiz , Dames, Joanna F
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/453449 , vital:75255 , ISBN , https://doi.org/10.1007/978-1-4614-6108-1_4
- Description: Abiotic stress tolerance in plants is gaining importance day by day. Different techniques are being employed to develop salt tolerant plants that directly or indirectly combat global food problems. Advanced comprehension of stress signal perception and transduction of associated molecular networks is now possible with the development in functional genomics and high throughput sequencing. In plant stress tolerance various genes, proteins, transcription factors, DNA histone-modifying enzymes, and several metabolites are playing very important role in stress tolerance. Determination of genomes of Arabidopsis, Oryza sativa spp. japonica cv. Nipponbare and integration of omics approach has augmented our knowledge pertaining to salt tolerance mechanisms of plants in natural environments. Application of transcriptomics, metabolomics, bioinformatics, and high-through-put DNA sequencing has enabled active analyses of regulatory networks that control abiotic stress responses. To unravel and exploit the function of genes is a major challenge of the post genomic era. This chapter therefore reviews the effect of salt stress on plants and the mechanism of salinity tolerance along with contributory roles of QTL, microRNA, microarray and proteomics.
- Full Text:
- Date Issued: 2013
- Authors: Kumar, Ashwani , Gupta, Aditi , Azooz, M M , Sharma, S , Ahmad, Parvaiz , Dames, Joanna F
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/453449 , vital:75255 , ISBN , https://doi.org/10.1007/978-1-4614-6108-1_4
- Description: Abiotic stress tolerance in plants is gaining importance day by day. Different techniques are being employed to develop salt tolerant plants that directly or indirectly combat global food problems. Advanced comprehension of stress signal perception and transduction of associated molecular networks is now possible with the development in functional genomics and high throughput sequencing. In plant stress tolerance various genes, proteins, transcription factors, DNA histone-modifying enzymes, and several metabolites are playing very important role in stress tolerance. Determination of genomes of Arabidopsis, Oryza sativa spp. japonica cv. Nipponbare and integration of omics approach has augmented our knowledge pertaining to salt tolerance mechanisms of plants in natural environments. Application of transcriptomics, metabolomics, bioinformatics, and high-through-put DNA sequencing has enabled active analyses of regulatory networks that control abiotic stress responses. To unravel and exploit the function of genes is a major challenge of the post genomic era. This chapter therefore reviews the effect of salt stress on plants and the mechanism of salinity tolerance along with contributory roles of QTL, microRNA, microarray and proteomics.
- Full Text:
- Date Issued: 2013
Genetics and thermal biology of littorinid snails of the genera Afrolittorina, Echinolittorina and Littoraria (Gastropoda: Littorinidae) from temperate, subtropical and tropical regions
- Authors: Matumba, Tshifhiwa Given
- Date: 2013
- Subjects: Littorinidae -- South Africa Littorinidae -- Brunei Littorinidae -- Adaptation -- South Africa Littorinidae -- Adaptation -- Brunei Littorinidae -- Effect of temperature on -- South Africa Littorinidae -- Effect of temperature on -- Brunei Littorinidae -- Physiology Snails -- South Africa Snails -- Brunei Gastropoda -- South Africa Gastropoda -- Brunei Intertidal animals -- South Africa Intertidal animals -- Brunei
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5588 , http://hdl.handle.net/10962/d1001953
- Description: With the anticipated effects of climate change due to global warming, there is concern over how animals, especially ectotherms, will respond to or tolerate extreme and fluctuating environmental temperature stress. Littorinid snails are intertidal ectotherms that live high on the shore where they experience both extreme and variable conditions of temperature and desiccation stress, and are believed to live close to their tolerance limits. This study investigated the thermal biology of littorinid snails of the genera Afrolittorina, Echinolittorina and Littoraria from temperate, subtropical and tropical regions in South Africa and Brunei Darussalam using thermal tolerance, heart function, and proteome approaches. The effects of conditions, such as rate of change in temperature, acclimation, heat shock, season and starvation were also tested. In addition, the evolutionary relationships and genetic diversity between and within the South African Afrolittorina spp. were investigated using mitochondrial and nuclear markers. Genetic results confirmed that these are two distinct species, with the brown to black A. knysnaensis predominant in the cool-temperate region of South Africa and the pale blue-grey A. africana in the subtropical region. There was low genetic variation and differentiation within each species, suggesting high gene flow among populations as a result of the effects of ocean currents on the dispersal of their planktotrophic larvae. Tests using exposure to high temperatures revealed differences in the thermal tolerances, heart performance and protein profiles of species from different latitudes, regions and zones on the shore. Thermal tolerance conformed to expectations, with clear, statistically significant trends from high tolerance in subtropical species to lower tolerance in temperate species. However, for Afrolittorina spp., there were no significant differences in the thermal tolerances of conspecifics from different regions, though there was a significant difference in thermal tolerance between juveniles and adults. Overall, adults of all species showed higher thermal tolerances than juveniles. Although lethal temperatures for these species were higher in summer than winter, laboratory acclimation had no effect on heat coma temperatures. All species showed some regulation of heart rate, with a degree of independence of heart rate from temperature across mid-range temperatures. The tropical species showed quick induction and good regulation of heart rate followed by the subtropical and temperate species, which displayed mixed responses including regulation, partial regulation and lack of regulation. Overall, tropical Echinolittorina spp. showed good regulation, while the subtropical E. natalensis and Littoraria glabrata exhibited a mixture of partial regulation and regulation. The subtropical/temperate Afrolittorina spp. showed high individual variability, some animals exhibiting regulation, while others did not. These effects seem to be largely phylogenetically determined as there were no differences in the heart rate responses of Afrolittorina spp. from different regions. The temperatures at which heart rate became independent of temperature (thermoneutral zone) were within the range experienced under natural conditions. In addition, there were differences in Arrhenius breakpoint and endpoint temperatures, showing a trend from higher in tropical animals to lower for temperate animals. Conditions such as acclimation, heat shock and starvation had little or no effect on heart performance. However, a slow increase in temperature induced good regulation of heart rate with noticeable shifts of breakpoints and endpoints for Afrolittorina spp. Lastly, there were differences in the proteome responses between and within Afrolittorina spp. as a function of species, size and treatment. Although both large and small A. knysnaensis had a greater number of protein spots in their proteome than A. africana (though the difference was not significant), the later showed significantly higher differential expression of certain proteins following heat stress. In addition, juveniles of both species displayed greater numbers of protein spots in their proteome than adults. The results indicate a difference in the physiological and biochemical responses (i.e. adaptations) of these snails to temperature, and this seems to relate to differences in biogeography, phylogeny, species identity and ecology. The ability to regulate heart rate is phylogenetically determined, while thresholds and lethal limits correspond to biogeography and species ecology. The proteome seems to correspond to species ecology. The results also indicate that these littorinids can tolerate high temperature stress and in this respect they are well suited to life in the intertidal zones or habitats where temperature and other stresses or conditions are extreme and can change abruptly. However, the limited ability of these snails to acclimate to different temperatures suggests that they are already living close to their tolerance limits with small safety margins or narrow thermal windows and so may be vulnerable to small rises in substratum temperature and/or solar radiation.
- Full Text:
- Date Issued: 2013
- Authors: Matumba, Tshifhiwa Given
- Date: 2013
- Subjects: Littorinidae -- South Africa Littorinidae -- Brunei Littorinidae -- Adaptation -- South Africa Littorinidae -- Adaptation -- Brunei Littorinidae -- Effect of temperature on -- South Africa Littorinidae -- Effect of temperature on -- Brunei Littorinidae -- Physiology Snails -- South Africa Snails -- Brunei Gastropoda -- South Africa Gastropoda -- Brunei Intertidal animals -- South Africa Intertidal animals -- Brunei
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5588 , http://hdl.handle.net/10962/d1001953
- Description: With the anticipated effects of climate change due to global warming, there is concern over how animals, especially ectotherms, will respond to or tolerate extreme and fluctuating environmental temperature stress. Littorinid snails are intertidal ectotherms that live high on the shore where they experience both extreme and variable conditions of temperature and desiccation stress, and are believed to live close to their tolerance limits. This study investigated the thermal biology of littorinid snails of the genera Afrolittorina, Echinolittorina and Littoraria from temperate, subtropical and tropical regions in South Africa and Brunei Darussalam using thermal tolerance, heart function, and proteome approaches. The effects of conditions, such as rate of change in temperature, acclimation, heat shock, season and starvation were also tested. In addition, the evolutionary relationships and genetic diversity between and within the South African Afrolittorina spp. were investigated using mitochondrial and nuclear markers. Genetic results confirmed that these are two distinct species, with the brown to black A. knysnaensis predominant in the cool-temperate region of South Africa and the pale blue-grey A. africana in the subtropical region. There was low genetic variation and differentiation within each species, suggesting high gene flow among populations as a result of the effects of ocean currents on the dispersal of their planktotrophic larvae. Tests using exposure to high temperatures revealed differences in the thermal tolerances, heart performance and protein profiles of species from different latitudes, regions and zones on the shore. Thermal tolerance conformed to expectations, with clear, statistically significant trends from high tolerance in subtropical species to lower tolerance in temperate species. However, for Afrolittorina spp., there were no significant differences in the thermal tolerances of conspecifics from different regions, though there was a significant difference in thermal tolerance between juveniles and adults. Overall, adults of all species showed higher thermal tolerances than juveniles. Although lethal temperatures for these species were higher in summer than winter, laboratory acclimation had no effect on heat coma temperatures. All species showed some regulation of heart rate, with a degree of independence of heart rate from temperature across mid-range temperatures. The tropical species showed quick induction and good regulation of heart rate followed by the subtropical and temperate species, which displayed mixed responses including regulation, partial regulation and lack of regulation. Overall, tropical Echinolittorina spp. showed good regulation, while the subtropical E. natalensis and Littoraria glabrata exhibited a mixture of partial regulation and regulation. The subtropical/temperate Afrolittorina spp. showed high individual variability, some animals exhibiting regulation, while others did not. These effects seem to be largely phylogenetically determined as there were no differences in the heart rate responses of Afrolittorina spp. from different regions. The temperatures at which heart rate became independent of temperature (thermoneutral zone) were within the range experienced under natural conditions. In addition, there were differences in Arrhenius breakpoint and endpoint temperatures, showing a trend from higher in tropical animals to lower for temperate animals. Conditions such as acclimation, heat shock and starvation had little or no effect on heart performance. However, a slow increase in temperature induced good regulation of heart rate with noticeable shifts of breakpoints and endpoints for Afrolittorina spp. Lastly, there were differences in the proteome responses between and within Afrolittorina spp. as a function of species, size and treatment. Although both large and small A. knysnaensis had a greater number of protein spots in their proteome than A. africana (though the difference was not significant), the later showed significantly higher differential expression of certain proteins following heat stress. In addition, juveniles of both species displayed greater numbers of protein spots in their proteome than adults. The results indicate a difference in the physiological and biochemical responses (i.e. adaptations) of these snails to temperature, and this seems to relate to differences in biogeography, phylogeny, species identity and ecology. The ability to regulate heart rate is phylogenetically determined, while thresholds and lethal limits correspond to biogeography and species ecology. The proteome seems to correspond to species ecology. The results also indicate that these littorinids can tolerate high temperature stress and in this respect they are well suited to life in the intertidal zones or habitats where temperature and other stresses or conditions are extreme and can change abruptly. However, the limited ability of these snails to acclimate to different temperatures suggests that they are already living close to their tolerance limits with small safety margins or narrow thermal windows and so may be vulnerable to small rises in substratum temperature and/or solar radiation.
- Full Text:
- Date Issued: 2013