Social needs as a driver of social innovation
- Authors: Dunn, Nicole Luciélle
- Date: 2018
- Subjects: Social change , Social evolution Social entrepreneurship Community development -- Social conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/21823 , vital:29782
- Description: Social innovation has been contextualised as a new way of resolving deeply entrenched development issues. The identification and resolution of social needs is said to be the driving force of social innovation. With features such as sustainability and scalability, social innovation has the potential to change the way we perceive and engage with development in the future. This research takes a critical look at how the social needs as a means to an end of social innovation, is identified. Previous research did not investigate the methodology of how these needs were identified and the question then arose as to how responsive the corresponding resolutions could be in resolving the need. Interviews were conducted with the founders of organisations that were considered socially innovative. Each founder was asked to detail the processes that took place in the social need identification that their respective organisation sought to resolve along with their personal journey towards becoming a founder, to gain a rich understanding of what shaped their approach to need identification. Organisations that were most critically responsive to the social needs identified were those that either 1) personally experienced deprivation of a social need in their own lives, or 2) had extensive engagement and exposure to individuals who had personally experienced the deprivation of a social need. It was evident that both the identification and corresponding resolution of social needs for social innovation require an approach that holds experiencers of the deprivation at the nucleus of the resolution. This methodology needs to be incorporated in the theory of social innovation and implemented in practice.
- Full Text:
- Date Issued: 2018
- Authors: Dunn, Nicole Luciélle
- Date: 2018
- Subjects: Social change , Social evolution Social entrepreneurship Community development -- Social conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/21823 , vital:29782
- Description: Social innovation has been contextualised as a new way of resolving deeply entrenched development issues. The identification and resolution of social needs is said to be the driving force of social innovation. With features such as sustainability and scalability, social innovation has the potential to change the way we perceive and engage with development in the future. This research takes a critical look at how the social needs as a means to an end of social innovation, is identified. Previous research did not investigate the methodology of how these needs were identified and the question then arose as to how responsive the corresponding resolutions could be in resolving the need. Interviews were conducted with the founders of organisations that were considered socially innovative. Each founder was asked to detail the processes that took place in the social need identification that their respective organisation sought to resolve along with their personal journey towards becoming a founder, to gain a rich understanding of what shaped their approach to need identification. Organisations that were most critically responsive to the social needs identified were those that either 1) personally experienced deprivation of a social need in their own lives, or 2) had extensive engagement and exposure to individuals who had personally experienced the deprivation of a social need. It was evident that both the identification and corresponding resolution of social needs for social innovation require an approach that holds experiencers of the deprivation at the nucleus of the resolution. This methodology needs to be incorporated in the theory of social innovation and implemented in practice.
- Full Text:
- Date Issued: 2018
Women’s perceptions of successful financial retirement planning
- Authors: Durrheim, Meghan
- Date: 2018
- Subjects: Women -- Retirement -- South Africa -- Makhanda , Retirement -- Planning , Retirement income -- Planning , Women -- Finance, Personal , Retired women -- Finance, Personal , Regression analysis
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/60339 , vital:27771
- Description: Financial retirement planning is an important component in ensuring that individuals accumulate sufficient wealth for retirement. Previous research suggests that many individuals are unable to accumulate sufficient wealth for retirement with the problem being particularly acute for women as they tend to spend less time planning financially for retirement when compared to men. Consequently, many women are unable to accumulate sufficient wealth for retirement. Despite the growing need to investigate women’s financial retirement planning, much research tends to focus on financial retirement planning for males. Consequently, there is a growing need to investigate women’s perceptions of successful financial retirement planning, particularly in Grahamstown. After conducting an in-depth literature study and using the study done by Doa (2014), six independent variables were identified: values, time horizon, attitudes, working life-cycle, risk tolerance and financial literacy. These independent variables were identified as factors which could potentially influence women’s perceptions of successful financial retirement planning. A set of hypothesis were formulated to test the relationship between these independent variables and the dependent variable (women’s perceptions of successful financial retirement planning). The study comprised of 101 participants. A principle component analysis was performed to determine the key variables, with the relevant independent factors being renamed: cultural values, personal values, affective attitudes, time horizon knowledge, time horizon consideration, risk tolerance, financial literacy. An ordinal logit regression analysis was then conducted on these renamed variables to determine the influence of these key independent variables on the dependent variable. After controlling for a set of demographic variables the results of the ordinal logit regression analysis revealed that only affective attitudes, time horizon knowledge, and personal values had a significant relationship with women’s perceptions of successful financial retirement planning. Cronbach’s alpha revealed that the measuring instrument of the significant extracted factors was reliable, while Pearson product moment was used to determine correlations between extracted key independent variables and the dependent variable. The investigation into women’s perceptions of successful financial retirement planning enabled insightful information to be gathered which adds to the body of knowledge. In addition, recommendations were formulated in an attempt to assist women when making financial retirement decisions.
- Full Text:
- Date Issued: 2018
- Authors: Durrheim, Meghan
- Date: 2018
- Subjects: Women -- Retirement -- South Africa -- Makhanda , Retirement -- Planning , Retirement income -- Planning , Women -- Finance, Personal , Retired women -- Finance, Personal , Regression analysis
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/60339 , vital:27771
- Description: Financial retirement planning is an important component in ensuring that individuals accumulate sufficient wealth for retirement. Previous research suggests that many individuals are unable to accumulate sufficient wealth for retirement with the problem being particularly acute for women as they tend to spend less time planning financially for retirement when compared to men. Consequently, many women are unable to accumulate sufficient wealth for retirement. Despite the growing need to investigate women’s financial retirement planning, much research tends to focus on financial retirement planning for males. Consequently, there is a growing need to investigate women’s perceptions of successful financial retirement planning, particularly in Grahamstown. After conducting an in-depth literature study and using the study done by Doa (2014), six independent variables were identified: values, time horizon, attitudes, working life-cycle, risk tolerance and financial literacy. These independent variables were identified as factors which could potentially influence women’s perceptions of successful financial retirement planning. A set of hypothesis were formulated to test the relationship between these independent variables and the dependent variable (women’s perceptions of successful financial retirement planning). The study comprised of 101 participants. A principle component analysis was performed to determine the key variables, with the relevant independent factors being renamed: cultural values, personal values, affective attitudes, time horizon knowledge, time horizon consideration, risk tolerance, financial literacy. An ordinal logit regression analysis was then conducted on these renamed variables to determine the influence of these key independent variables on the dependent variable. After controlling for a set of demographic variables the results of the ordinal logit regression analysis revealed that only affective attitudes, time horizon knowledge, and personal values had a significant relationship with women’s perceptions of successful financial retirement planning. Cronbach’s alpha revealed that the measuring instrument of the significant extracted factors was reliable, while Pearson product moment was used to determine correlations between extracted key independent variables and the dependent variable. The investigation into women’s perceptions of successful financial retirement planning enabled insightful information to be gathered which adds to the body of knowledge. In addition, recommendations were formulated in an attempt to assist women when making financial retirement decisions.
- Full Text:
- Date Issued: 2018
Governance mapping: a framework for assessing the adaptive capacity of marine resource governance to environmental change
- Dutra, Leo X C, Sporne, Ilva, Haward, Marcus, Aswani, Shankar, Cochrane, Kevern L, Frusher, Stewart, Gasalla, Maria A, Gianesella, Sônia M F, Grant, Tanith, Hobday, Alistair J, Jennings, Sarah, Plagányi, Éva, Pecl, Gretta T, Salim, Shyam S, Sauer, Warwick H H, Taboada, Manuela B, Van Putten, Ingrid E
- Authors: Dutra, Leo X C , Sporne, Ilva , Haward, Marcus , Aswani, Shankar , Cochrane, Kevern L , Frusher, Stewart , Gasalla, Maria A , Gianesella, Sônia M F , Grant, Tanith , Hobday, Alistair J , Jennings, Sarah , Plagányi, Éva , Pecl, Gretta T , Salim, Shyam S , Sauer, Warwick H H , Taboada, Manuela B , Van Putten, Ingrid E
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145336 , vital:38429 , DOI: 10.1016/j.marpol.2018.12.011
- Description: Marine social-ecological systems are influenced by the way humans interact with their environment, and external forces, which change and re-shape the environment. In many regions, exploitation of marine resources and climate change are two of the primary drivers shifting the abundance and distribution of marine living resources, with negative effects on marine-dependent communities. Governance systems determine ‘who’ makes decisions, ‘what’ are their powers and responsibilities, and ‘how’ they are exercised. Understanding the connections between the actors comprising governance systems and influences between governance and the environment is therefore critical to support successful transitions to novel forms of governance required to deal with environmental changes. The paper provides an analytical framework with a practical example from Vanuatu, for mapping and assessment of the governance system providing for management of coral reef fish resources. The framework enables a rapid analysis of governance systems to identify factors that can encourage, or hinder, the adaptation of communities to changes in abundance or availability of marine resources.
- Full Text:
- Date Issued: 2019
- Authors: Dutra, Leo X C , Sporne, Ilva , Haward, Marcus , Aswani, Shankar , Cochrane, Kevern L , Frusher, Stewart , Gasalla, Maria A , Gianesella, Sônia M F , Grant, Tanith , Hobday, Alistair J , Jennings, Sarah , Plagányi, Éva , Pecl, Gretta T , Salim, Shyam S , Sauer, Warwick H H , Taboada, Manuela B , Van Putten, Ingrid E
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145336 , vital:38429 , DOI: 10.1016/j.marpol.2018.12.011
- Description: Marine social-ecological systems are influenced by the way humans interact with their environment, and external forces, which change and re-shape the environment. In many regions, exploitation of marine resources and climate change are two of the primary drivers shifting the abundance and distribution of marine living resources, with negative effects on marine-dependent communities. Governance systems determine ‘who’ makes decisions, ‘what’ are their powers and responsibilities, and ‘how’ they are exercised. Understanding the connections between the actors comprising governance systems and influences between governance and the environment is therefore critical to support successful transitions to novel forms of governance required to deal with environmental changes. The paper provides an analytical framework with a practical example from Vanuatu, for mapping and assessment of the governance system providing for management of coral reef fish resources. The framework enables a rapid analysis of governance systems to identify factors that can encourage, or hinder, the adaptation of communities to changes in abundance or availability of marine resources.
- Full Text:
- Date Issued: 2019
The impact of performance and reward on employee engagement
- Dwane, Ithembekil’Inkosi Den-Boy
- Authors: Dwane, Ithembekil’Inkosi Den-Boy
- Date: 2018
- Subjects: Performance -- Management , Employee motivation Employees -- Attitudes Management -- Employee participation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/29940 , vital:30797
- Description: In today’s increasing competitive environment employees look for organisations that best meet their expectations. Few barriers prevent mobility of employees between companies, therefore employees may easily change from one organisation to another should they feel that they are not fully challenged and engaged. In a global environment where maintaining competitive advantage is of paramount importance, it is essential to develop effective retention strategies. In order to retain employees companies must try to offer an engaging environment to employees in order to satisfy these expectations in a different way from their competitors with a compelling value and attempts to increase performance and engagement amongst their employees. Nonetheless, employers are more aware now of the importance of an engaged workforce as a way of gaining competitive advantage in these challenging times, where employee attrition is high. Therefore retaining skilled and talented employees has become one of the major challenges faced by all sectors in South Africa, especially the financial sector as a whole. In order to alleviate this challenge companies have developed a robust performance management system and reward initiatives that enhance engagement. This study aimed to explore the impact of performance and reward on employee engagement, and to contribute to the human resource management science literature. The study also aimed to make recommendations on the management factors that determine these variables. The literature review explored traditional and emerging concepts, importance of employee engagement, types and characteristics of engaged II employees. The researcher further elaborated on the literature by including engagement factors, barriers and models. The second chapter of the literature then covered the concept of performance (individual and team) in detail and the concept of reward (extrinsic and intrinsic). From the literature review a performance, reward and engagement questionnaire was designed to find empirical responses to these challenges. The study adopted a quantitative approach (N = 275) testing the relationship of performance and reward (extrinsic and intrinsic) on the dependent variable, employee engagement. The study also entailed a cross sectional design approach. Minitab version 18 was used to conduct the statistical analysis. The findings support a strong correlation between the performance and employee engagement. The findings also indicate that there is a strong correlation between reward (extrinsic and intrinsic) and employee engagement across all employees. From the research findings there is also a strong correlation between the performance and employee engagement. The findings also indicate that there is a strong correlation between reward (extrinsic and intrinsic) and employee engagement across all employees that formed part of this research. The main findings also include some insights for organisations to consider and recommendations for future research.
- Full Text:
- Date Issued: 2018
- Authors: Dwane, Ithembekil’Inkosi Den-Boy
- Date: 2018
- Subjects: Performance -- Management , Employee motivation Employees -- Attitudes Management -- Employee participation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/29940 , vital:30797
- Description: In today’s increasing competitive environment employees look for organisations that best meet their expectations. Few barriers prevent mobility of employees between companies, therefore employees may easily change from one organisation to another should they feel that they are not fully challenged and engaged. In a global environment where maintaining competitive advantage is of paramount importance, it is essential to develop effective retention strategies. In order to retain employees companies must try to offer an engaging environment to employees in order to satisfy these expectations in a different way from their competitors with a compelling value and attempts to increase performance and engagement amongst their employees. Nonetheless, employers are more aware now of the importance of an engaged workforce as a way of gaining competitive advantage in these challenging times, where employee attrition is high. Therefore retaining skilled and talented employees has become one of the major challenges faced by all sectors in South Africa, especially the financial sector as a whole. In order to alleviate this challenge companies have developed a robust performance management system and reward initiatives that enhance engagement. This study aimed to explore the impact of performance and reward on employee engagement, and to contribute to the human resource management science literature. The study also aimed to make recommendations on the management factors that determine these variables. The literature review explored traditional and emerging concepts, importance of employee engagement, types and characteristics of engaged II employees. The researcher further elaborated on the literature by including engagement factors, barriers and models. The second chapter of the literature then covered the concept of performance (individual and team) in detail and the concept of reward (extrinsic and intrinsic). From the literature review a performance, reward and engagement questionnaire was designed to find empirical responses to these challenges. The study adopted a quantitative approach (N = 275) testing the relationship of performance and reward (extrinsic and intrinsic) on the dependent variable, employee engagement. The study also entailed a cross sectional design approach. Minitab version 18 was used to conduct the statistical analysis. The findings support a strong correlation between the performance and employee engagement. The findings also indicate that there is a strong correlation between reward (extrinsic and intrinsic) and employee engagement across all employees. From the research findings there is also a strong correlation between the performance and employee engagement. The findings also indicate that there is a strong correlation between reward (extrinsic and intrinsic) and employee engagement across all employees that formed part of this research. The main findings also include some insights for organisations to consider and recommendations for future research.
- Full Text:
- Date Issued: 2018
Rose-scented geranium oil yield and composition as affected by leaf age, herbage drying and paclobutrazol
- Authors: Dyafta, Viwe
- Date: 2018
- Subjects: Essences and essential oils Rose geranium oil
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10747 , vital:35733
- Description: Essential oil of rose scented-geranium is highly versatile and this makes it a very important essential oil in aromatherapy, medicine and cosmetics as well as in flavouring of food and drinks for different industries. The value of the essential oil is directly related to the quality of the oil. Therefore, it is important that the geranium growers take good care of agricultural practices in the production of essential oils as it is a crucial step where oil quality and yield is either obtained or lost. Thus, growing conditions and harvesting time must be cautiously established and controlled including herbage drying to ensure optimum yields and high quality of rose-scented geranium oil. The geranium oil production industry in South Africa is still expanding and oil yield & quality variation is important. This study was undertaken to determine the effects of herbage drying and method, leaf age and paclobutrazol concentrations on oil yield and quality of rose-scented geranium. The responses of oil yield and quality to drying effect was conducted on plant materials which were harvested from the University of Fort Hare Research Farm and glasshouse in December 2014 and October 2015. To determine the effect of drying method on essential oil yield and composition of rose-scented geranium the harvested leaves were dried in direct sunlight (20-35℃) and in a shade conditions (25℃/room temperature). Essential oil was obtained by hydro-distillation using a Clevenger apparatus. The oil samples were analysed by gas chromatography (GC) at the Dohne Agricultural institute. The major components of the oil conducted under the shade method were Linalool (5.58 percent), Menthone (0.68 percent), Citronellol (36.14 percent), Geraniol (7.29 percent), CitronellylFormate (15.39 percent) and GeranylFormate (3.30 percent), whereas those that were sun dried comprised of Linalool (3.56percent), Menthone (0.76 percent), Citronellol (32.25 percent), Geraniol (6.49 percent), CitronellylFormate (14.84 percent) and GeranylFormate (3.15 percent). The analysis of variance showed that freshly dried herbage followed by shade drying is suitable for highest oil yield. In addition, changes in essential oil composition and oil yield with leaf age in rose-scented geranium (Pelargonium capitatum x P. radens cv. Rose) were investigated in a glasshouse of the University of Fort Hare, during January to April and April to August 2012. The plants were allowed to grow to about 12-leaf stage. From top to bottom, the leaves were put into five groups (each group comprising two successive leaves, Pairs 1, 2, 3, 4 and 5). Leaf growth (leaf fresh and dry mass), and essential oil yield and composition data were collected and compared. The results indicated that, leaf fresh and dry mass data were significantly lower in the top-most (youngest leaves) as compared with the rest of the leaf pairs harvested. Essential oil in the youngest leaves was colourless, but as the leaves advanced with age, the oil tended to have a blue-green colour. Oil content (on dry mass basis) from the top to bottom, for Leaf Pairs 1, 2, 3, 4, and 5 were about 7.0, 4.9, 3.2, 2.4, 1.9 percent, respectively. Oil yield showed a significant increase in the second youngest pair of leaves and progressively declined, resulting in a significant lower yield in the oldest leaves. Leaf Pairs 1, 2, 3, 4 and 5, contributed about 19.3, 22.0, 17.71, 12.03 and 8.5 percent of the total yield per branch, respectively. Citronellol:Geraniol ratio was significantly lower in the young leaves than in the old leaves. Linalool and Geranylformate concentrations were the highest in the youngest leaves, and the opposite was observed in isomenthone. Other essential oil components did respond to leaf age. In support of research by Góra et al. (2002), Motsa et al. (2006) and Southwell and Stiff (1989), the current results indicate that early leaf age affects essential oil yield and composition. Thus, shorter regrowth cycles would increase essential oil yield and quality of rose-scented geranium. The paclobutrazol experiment was conducted in a glasshouse at the University of Fort Hare, Alice. A randomized complete block design with four replications was applied. One month after cutting back of the plants, PBZ was applied at the rates of 0, 100, 200 and 300 mg/l on the regrowth and harvested at four months of age. Data, such as chlorophyll content, plant circumference, plant height, fresh and dry mass and oil composition, were determined. The results highlighted that with an increase in PBZ concentration, total herbage mass and plant height tended to decline (Esmaielpour et al., 2011). Thus, in most cases herbage fresh and dry weight of treated plants had lower weight than the control. Paclobutrazol significantly reduced canopy circumference. There was no significant difference (P< 0.05) in oil yield and composition. Furthermore, observations showed that plants receiving PBZ had a deep green colour although the chlorophyll data did not show a significant difference. These results clearly show that PBZ helps geranium plants with compact canopy, which would enable farmers to increase income by increasing planting density, reducing distillation cost of the herbage volume and mass without reducing oil yield per plant. The findings, add another dimension to practical use of this hormone for commercial cultivation.
- Full Text:
- Date Issued: 2018
- Authors: Dyafta, Viwe
- Date: 2018
- Subjects: Essences and essential oils Rose geranium oil
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10747 , vital:35733
- Description: Essential oil of rose scented-geranium is highly versatile and this makes it a very important essential oil in aromatherapy, medicine and cosmetics as well as in flavouring of food and drinks for different industries. The value of the essential oil is directly related to the quality of the oil. Therefore, it is important that the geranium growers take good care of agricultural practices in the production of essential oils as it is a crucial step where oil quality and yield is either obtained or lost. Thus, growing conditions and harvesting time must be cautiously established and controlled including herbage drying to ensure optimum yields and high quality of rose-scented geranium oil. The geranium oil production industry in South Africa is still expanding and oil yield & quality variation is important. This study was undertaken to determine the effects of herbage drying and method, leaf age and paclobutrazol concentrations on oil yield and quality of rose-scented geranium. The responses of oil yield and quality to drying effect was conducted on plant materials which were harvested from the University of Fort Hare Research Farm and glasshouse in December 2014 and October 2015. To determine the effect of drying method on essential oil yield and composition of rose-scented geranium the harvested leaves were dried in direct sunlight (20-35℃) and in a shade conditions (25℃/room temperature). Essential oil was obtained by hydro-distillation using a Clevenger apparatus. The oil samples were analysed by gas chromatography (GC) at the Dohne Agricultural institute. The major components of the oil conducted under the shade method were Linalool (5.58 percent), Menthone (0.68 percent), Citronellol (36.14 percent), Geraniol (7.29 percent), CitronellylFormate (15.39 percent) and GeranylFormate (3.30 percent), whereas those that were sun dried comprised of Linalool (3.56percent), Menthone (0.76 percent), Citronellol (32.25 percent), Geraniol (6.49 percent), CitronellylFormate (14.84 percent) and GeranylFormate (3.15 percent). The analysis of variance showed that freshly dried herbage followed by shade drying is suitable for highest oil yield. In addition, changes in essential oil composition and oil yield with leaf age in rose-scented geranium (Pelargonium capitatum x P. radens cv. Rose) were investigated in a glasshouse of the University of Fort Hare, during January to April and April to August 2012. The plants were allowed to grow to about 12-leaf stage. From top to bottom, the leaves were put into five groups (each group comprising two successive leaves, Pairs 1, 2, 3, 4 and 5). Leaf growth (leaf fresh and dry mass), and essential oil yield and composition data were collected and compared. The results indicated that, leaf fresh and dry mass data were significantly lower in the top-most (youngest leaves) as compared with the rest of the leaf pairs harvested. Essential oil in the youngest leaves was colourless, but as the leaves advanced with age, the oil tended to have a blue-green colour. Oil content (on dry mass basis) from the top to bottom, for Leaf Pairs 1, 2, 3, 4, and 5 were about 7.0, 4.9, 3.2, 2.4, 1.9 percent, respectively. Oil yield showed a significant increase in the second youngest pair of leaves and progressively declined, resulting in a significant lower yield in the oldest leaves. Leaf Pairs 1, 2, 3, 4 and 5, contributed about 19.3, 22.0, 17.71, 12.03 and 8.5 percent of the total yield per branch, respectively. Citronellol:Geraniol ratio was significantly lower in the young leaves than in the old leaves. Linalool and Geranylformate concentrations were the highest in the youngest leaves, and the opposite was observed in isomenthone. Other essential oil components did respond to leaf age. In support of research by Góra et al. (2002), Motsa et al. (2006) and Southwell and Stiff (1989), the current results indicate that early leaf age affects essential oil yield and composition. Thus, shorter regrowth cycles would increase essential oil yield and quality of rose-scented geranium. The paclobutrazol experiment was conducted in a glasshouse at the University of Fort Hare, Alice. A randomized complete block design with four replications was applied. One month after cutting back of the plants, PBZ was applied at the rates of 0, 100, 200 and 300 mg/l on the regrowth and harvested at four months of age. Data, such as chlorophyll content, plant circumference, plant height, fresh and dry mass and oil composition, were determined. The results highlighted that with an increase in PBZ concentration, total herbage mass and plant height tended to decline (Esmaielpour et al., 2011). Thus, in most cases herbage fresh and dry weight of treated plants had lower weight than the control. Paclobutrazol significantly reduced canopy circumference. There was no significant difference (P< 0.05) in oil yield and composition. Furthermore, observations showed that plants receiving PBZ had a deep green colour although the chlorophyll data did not show a significant difference. These results clearly show that PBZ helps geranium plants with compact canopy, which would enable farmers to increase income by increasing planting density, reducing distillation cost of the herbage volume and mass without reducing oil yield per plant. The findings, add another dimension to practical use of this hormone for commercial cultivation.
- Full Text:
- Date Issued: 2018
Selected benefits, challenges and lessons experiences by the 2015-16 feesmustfall leaders at the University of Fort Hare (UFH), East London Campus (EL)
- Authors: Dyakumeni, Monica
- Date: 2018
- Subjects: Student movements -- South Africa Universities and colleges -- South Africa -- Eastern Cape Education, Higher -- South Africa
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/11075 , vital:37028
- Description: There is a high amount of journalistic and academic work that has been produced to highlight the various benefits, challenges and lessons the 2015-2016 #Feesmustfall movement (henceforth, FMFM) brought in its wake for South African universities affected and for South African society in general. Save for the University of the Witwatersrand (activists from Wits produced a book on their involvement in FMF), there is a dearth of academic research on the benefits, challenges and lessons of FMF as experienced by students from affected universities, in general, and student activists and leaders, in particular. The current research study was conducted to fill the above gap, and it adopted a qualitative research philosophy in the manner the research was conducted. For the purposes of this research, 10 male FMF activists from the University of Fort Hare, East London, Eastern Cape, were interviewed using an in-depth interview technique about what they regarded as benefits, challenges and lessons stemming from their involvement as leaders of the FMF protests in their campus. The findings largely set a tone of caution that there are important considerations to be made when looking at the issue of university-based protests such as FMF; in particular, the physical and psychological impacts of these protests on student leaders, or activists. The results in this study demonstrate that those who led the 2015/6 FMF protests at UFH, EL, experienced intellectual and political leadership growth as young student leaders, among some benefits. The benefits, however, were tempered by some of the traumatic and disturbing events, which exposed these leaders to, among other things, police violence, arrests and serious psychological discomfort during and even after the protests. The results also demonstrate some continuing positive impact of the FMFM on those who led the students at UFH, that is, they are today using the knowledge and lessons from FMF to make their workplaces and their political organization’s processes more robust and democratic. These findings are significant, especially for universities in South Africa, and in Africa as a whole, as there are researchers who caution that the South African university management is quick to resort to student repression during protests. The study then goes on to discuss the relevance of the findings for universities, the state and the student activists themselves. Areas for future research are also proffered.
- Full Text:
- Date Issued: 2018
- Authors: Dyakumeni, Monica
- Date: 2018
- Subjects: Student movements -- South Africa Universities and colleges -- South Africa -- Eastern Cape Education, Higher -- South Africa
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/11075 , vital:37028
- Description: There is a high amount of journalistic and academic work that has been produced to highlight the various benefits, challenges and lessons the 2015-2016 #Feesmustfall movement (henceforth, FMFM) brought in its wake for South African universities affected and for South African society in general. Save for the University of the Witwatersrand (activists from Wits produced a book on their involvement in FMF), there is a dearth of academic research on the benefits, challenges and lessons of FMF as experienced by students from affected universities, in general, and student activists and leaders, in particular. The current research study was conducted to fill the above gap, and it adopted a qualitative research philosophy in the manner the research was conducted. For the purposes of this research, 10 male FMF activists from the University of Fort Hare, East London, Eastern Cape, were interviewed using an in-depth interview technique about what they regarded as benefits, challenges and lessons stemming from their involvement as leaders of the FMF protests in their campus. The findings largely set a tone of caution that there are important considerations to be made when looking at the issue of university-based protests such as FMF; in particular, the physical and psychological impacts of these protests on student leaders, or activists. The results in this study demonstrate that those who led the 2015/6 FMF protests at UFH, EL, experienced intellectual and political leadership growth as young student leaders, among some benefits. The benefits, however, were tempered by some of the traumatic and disturbing events, which exposed these leaders to, among other things, police violence, arrests and serious psychological discomfort during and even after the protests. The results also demonstrate some continuing positive impact of the FMFM on those who led the students at UFH, that is, they are today using the knowledge and lessons from FMF to make their workplaces and their political organization’s processes more robust and democratic. These findings are significant, especially for universities in South Africa, and in Africa as a whole, as there are researchers who caution that the South African university management is quick to resort to student repression during protests. The study then goes on to discuss the relevance of the findings for universities, the state and the student activists themselves. Areas for future research are also proffered.
- Full Text:
- Date Issued: 2018
The role of ecological processes in structuring reef fish communities in the Agulhas Ecoregion, South Africa
- Authors: Dyer, Alexander
- Date: 2018
- Subjects: Reef fishes -- South Africa -- Agulhas, Cape (Cape) , Reef fishes -- Ecology -- South Africa -- Agulhas, Cape (Cape) , Marine biodiversity -- South Africa -- Agulhas, Cape (Cape) , Biotic communities -- South Africa -- Agulhas, Cape (Cape) , Sparidae -- South Africa -- Agulhas, Cape (Cape) , Reef fishes -- Size -- South Africa -- Agulhas, Cape (Cape) , Baited remote underwater stereo-video systems (stereo-BRUVs)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63899 , vital:28504
- Description: Local, niche-based processes, which arise from the interplay between biotic interactions and abiotic constraints are considered to be important regulators of community structure. However, it is increasingly recognised that patterns of diversity can also be strongly influenced by dispersal-driven processes. While empirical research on the diversity of coral reef fishes on shallow tropical reefs has contributed greatly to the development of general concepts in ecology, there have been considerably fewer studies on the processes which shape the diversity of fish communities on shallow (10 - 30 m) and deep (30 - 75 m) rocky reefs. Consequently, it is less clear at which spatial scales niche partitioning and dispersal limitation contribute most strongly to the structure of reef-associated fish communities within rocky reef ecosystems. To address this caveat, research was conducted at four rocky reef complexes within the warm-temperate Agulhas Ecoregion, South Africa. The diversity of reef-associated fishes was sampled by baited remote underwater stereo-video systems (stereo-BRUVs) to incorporate the range of heterogeneous reef habitat in Tsitsikamma National Park Marine Protected Area (TNP MPA) and Algoa Bay (AB). To examine how niche-based and dispersal-driven processes influence patterns of diversity among species within the dominant family of resident fishes, the sparids (Sparidae), components of diversity were quantified at several spatial scales. Turnover in the number of species which locally co-occurred was found to be largely driven by the limited dispersal of species over hundreds of kilometres. When relative species abundances were taken into account, sparid communities were characterised by higher than expected rates of compositional turnover among local habitat patches separated by hundreds to thousands of metres of contiguous reef. Patterns of compositional turnover were associated with the spatial aggregation of conspecifics, particularly at scales which facilitate the post-settlement dispersal of fishes. Niche-based segregation of species along the depth gradient was found to be the primary driver of compositional turnover among both protected and exploited communities. However, spatial structuring within reefs, which was independent of variation in the environment, suggests that compositional differences among communities are also influenced by the limited post-settlement dispersal of resident fishes to adjacent areas during their ontogeny. Together, the results suggest that the diversity of reef-associated sparids is likely to depend both on an adequate diversity of suitable reef habitat and a sufficient degree of spatial connectivity to facilitate ontogenetic habitat shifts. Taxon-based descriptors of diversity do not adequately account for ecological difference among conspecifics within size-structured populations. To test whether differences in body size facilitated coexistence among sparid fishes, the number of species which coexisted at the local scale was related to variation in the size structure of communities. In communities which have been historically protected from fishing, local coexistence between a greater number of species was promoted by reduced levels of intraspecific variation in size of fishes. This suggests that, among species with similar trophic requirements, further niche segregation along a prey-size and body-size gradient is likely to mitigate the direct impacts of competition for shared food resources. Among exploited communities, size structure did not influence the number of species which coexisted at the local scale. This finding suggests that fishing-induced mortality of larger-bodied fishes is likely to remove some of the constraints to colonisation which arise from asymmetries in competitive fitness between small and large-bodied fishes. Together, these results highlight the importance of post-settlement processes and population size structure to the maintenance of reef-associated fish diversity within contiguous rocky reef habitats.
- Full Text:
- Date Issued: 2018
- Authors: Dyer, Alexander
- Date: 2018
- Subjects: Reef fishes -- South Africa -- Agulhas, Cape (Cape) , Reef fishes -- Ecology -- South Africa -- Agulhas, Cape (Cape) , Marine biodiversity -- South Africa -- Agulhas, Cape (Cape) , Biotic communities -- South Africa -- Agulhas, Cape (Cape) , Sparidae -- South Africa -- Agulhas, Cape (Cape) , Reef fishes -- Size -- South Africa -- Agulhas, Cape (Cape) , Baited remote underwater stereo-video systems (stereo-BRUVs)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63899 , vital:28504
- Description: Local, niche-based processes, which arise from the interplay between biotic interactions and abiotic constraints are considered to be important regulators of community structure. However, it is increasingly recognised that patterns of diversity can also be strongly influenced by dispersal-driven processes. While empirical research on the diversity of coral reef fishes on shallow tropical reefs has contributed greatly to the development of general concepts in ecology, there have been considerably fewer studies on the processes which shape the diversity of fish communities on shallow (10 - 30 m) and deep (30 - 75 m) rocky reefs. Consequently, it is less clear at which spatial scales niche partitioning and dispersal limitation contribute most strongly to the structure of reef-associated fish communities within rocky reef ecosystems. To address this caveat, research was conducted at four rocky reef complexes within the warm-temperate Agulhas Ecoregion, South Africa. The diversity of reef-associated fishes was sampled by baited remote underwater stereo-video systems (stereo-BRUVs) to incorporate the range of heterogeneous reef habitat in Tsitsikamma National Park Marine Protected Area (TNP MPA) and Algoa Bay (AB). To examine how niche-based and dispersal-driven processes influence patterns of diversity among species within the dominant family of resident fishes, the sparids (Sparidae), components of diversity were quantified at several spatial scales. Turnover in the number of species which locally co-occurred was found to be largely driven by the limited dispersal of species over hundreds of kilometres. When relative species abundances were taken into account, sparid communities were characterised by higher than expected rates of compositional turnover among local habitat patches separated by hundreds to thousands of metres of contiguous reef. Patterns of compositional turnover were associated with the spatial aggregation of conspecifics, particularly at scales which facilitate the post-settlement dispersal of fishes. Niche-based segregation of species along the depth gradient was found to be the primary driver of compositional turnover among both protected and exploited communities. However, spatial structuring within reefs, which was independent of variation in the environment, suggests that compositional differences among communities are also influenced by the limited post-settlement dispersal of resident fishes to adjacent areas during their ontogeny. Together, the results suggest that the diversity of reef-associated sparids is likely to depend both on an adequate diversity of suitable reef habitat and a sufficient degree of spatial connectivity to facilitate ontogenetic habitat shifts. Taxon-based descriptors of diversity do not adequately account for ecological difference among conspecifics within size-structured populations. To test whether differences in body size facilitated coexistence among sparid fishes, the number of species which coexisted at the local scale was related to variation in the size structure of communities. In communities which have been historically protected from fishing, local coexistence between a greater number of species was promoted by reduced levels of intraspecific variation in size of fishes. This suggests that, among species with similar trophic requirements, further niche segregation along a prey-size and body-size gradient is likely to mitigate the direct impacts of competition for shared food resources. Among exploited communities, size structure did not influence the number of species which coexisted at the local scale. This finding suggests that fishing-induced mortality of larger-bodied fishes is likely to remove some of the constraints to colonisation which arise from asymmetries in competitive fitness between small and large-bodied fishes. Together, these results highlight the importance of post-settlement processes and population size structure to the maintenance of reef-associated fish diversity within contiguous rocky reef habitats.
- Full Text:
- Date Issued: 2018
Characteristics and key-success factors of future sought-after retirement villages in George, South Africa
- Authors: Earle, Isak Sameul
- Date: 2018
- Subjects: Retirement communities -- South Africa -- George , Retirees -- Housing -- South Africa -- George Retirement -- South Africa -- George -- Planning Retirees -- South Africa -- George -- Economic conditions
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/22038 , vital:29815
- Description: This study is about obtaining information about international and national trends and features of sought-after retirement villages by means of a literature review (secondary research) as well as by means of a survey amongst estate agents and retirees currently residing in George (primary research). The primary research objective was to develop a Retirement Village Features Model (a set of features, development guidelines, conditions and requirements) for a sought-after retirement village in George, derived from scientific knowledge, resultant from findings and conclusions from primary and secondary research conducted by the researcher. The literature review revealed that worldwide, the population continues to get older and that the number of retirees requiring retirement homes is growing and supply is not keeping pace with the ever-growing demand. It also revealed 16 characteristics of retirement villages that were used as a basis for designing the questionnaire namely the expectation and the importance of: living amongst peers for social interaction, safety and security facilities, an easy-care lifestyle, economic investment security, recreational leisure facilities, beautiful designed buildings and homes, location, privacy, effective management of the development, well nurtured gardens, paved pedestrian walkways, wheelchair friendly designs, low maintenance housing designs, offering facilities for successful ageing, green energy design houses and facilities and the importance of not selling to potential buyers under the age of 50. Although the expectation of each of the 16 characteristics of a sought-after retirement village was high for most participants, the level of importance of each characteristic varied quite a lot. This might be a good indication that participants would like to have all the characteristics present in the development but are sceptical about costs that might be incurred to the homeowner having those characteristics present in the village. The participants in the study also indicated various desired characteristics of a future sought after retirement village that forms part of the Model which conforms to literature findings. These include: emergency assistance button in houses and emergency response services, a clubhouse with catering and braai facilities, WI-FI services in all areas, a pet-friendly environment with park for domestic animals and access to Frail Care and Assisted Living facilities. Participants in the survey also indicated their preference for housing in future sought-after retirement villages namely; 52.17% preferred a two bedroom privately owned home, 33.04% preferred a three bedroom privately owned house, 7.83% preferred renting a one or two-bedroom house and 6.96% prefer a one bedroom privately owned house. 71.31% of participants who responded regarded assisted living services and frail care services and facilities as very important or of utmost importance. This paper was aimed at capturing the essence of how retirees feel about their homes and lifestyle environments. By incorporating the findings and recommendations contained in this study into their development plans for future retirement villages, development companies will have a competitive advantage over their rivals in this industry. It is recommended that future research regarding retirement villages should include other regions in South Africa to improve the model. It is also recommended that further research can be done on how expected facilities in retirement villages can become self- sufficient and subsequently alleviating the maintenance costs for homeowners and hence rendering more value to the homeowner.
- Full Text:
- Date Issued: 2018
- Authors: Earle, Isak Sameul
- Date: 2018
- Subjects: Retirement communities -- South Africa -- George , Retirees -- Housing -- South Africa -- George Retirement -- South Africa -- George -- Planning Retirees -- South Africa -- George -- Economic conditions
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/22038 , vital:29815
- Description: This study is about obtaining information about international and national trends and features of sought-after retirement villages by means of a literature review (secondary research) as well as by means of a survey amongst estate agents and retirees currently residing in George (primary research). The primary research objective was to develop a Retirement Village Features Model (a set of features, development guidelines, conditions and requirements) for a sought-after retirement village in George, derived from scientific knowledge, resultant from findings and conclusions from primary and secondary research conducted by the researcher. The literature review revealed that worldwide, the population continues to get older and that the number of retirees requiring retirement homes is growing and supply is not keeping pace with the ever-growing demand. It also revealed 16 characteristics of retirement villages that were used as a basis for designing the questionnaire namely the expectation and the importance of: living amongst peers for social interaction, safety and security facilities, an easy-care lifestyle, economic investment security, recreational leisure facilities, beautiful designed buildings and homes, location, privacy, effective management of the development, well nurtured gardens, paved pedestrian walkways, wheelchair friendly designs, low maintenance housing designs, offering facilities for successful ageing, green energy design houses and facilities and the importance of not selling to potential buyers under the age of 50. Although the expectation of each of the 16 characteristics of a sought-after retirement village was high for most participants, the level of importance of each characteristic varied quite a lot. This might be a good indication that participants would like to have all the characteristics present in the development but are sceptical about costs that might be incurred to the homeowner having those characteristics present in the village. The participants in the study also indicated various desired characteristics of a future sought after retirement village that forms part of the Model which conforms to literature findings. These include: emergency assistance button in houses and emergency response services, a clubhouse with catering and braai facilities, WI-FI services in all areas, a pet-friendly environment with park for domestic animals and access to Frail Care and Assisted Living facilities. Participants in the survey also indicated their preference for housing in future sought-after retirement villages namely; 52.17% preferred a two bedroom privately owned home, 33.04% preferred a three bedroom privately owned house, 7.83% preferred renting a one or two-bedroom house and 6.96% prefer a one bedroom privately owned house. 71.31% of participants who responded regarded assisted living services and frail care services and facilities as very important or of utmost importance. This paper was aimed at capturing the essence of how retirees feel about their homes and lifestyle environments. By incorporating the findings and recommendations contained in this study into their development plans for future retirement villages, development companies will have a competitive advantage over their rivals in this industry. It is recommended that future research regarding retirement villages should include other regions in South Africa to improve the model. It is also recommended that further research can be done on how expected facilities in retirement villages can become self- sufficient and subsequently alleviating the maintenance costs for homeowners and hence rendering more value to the homeowner.
- Full Text:
- Date Issued: 2018
Health and fitness of young, healthy adult females and the effect of an eight week pilates intervention
- Authors: Eaton, Lara Lee
- Date: 2018
- Subjects: Physical fitness for women -- South Africa -- Makhanda , Pilates method , Exercise for women -- South Africa -- Makhanda , Exercise -- Health aspects -- South Africa -- Makhanda , Exercise -- Physiological aspects -- South Africa -- Makhanda
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/58267 , vital:27112
- Description: Purpose: The first phase of this study aimed to investigate the health and fitness status of young adult females in the local community. The second phase of this study investigated the impact of an eight week progressive Pilates intervention on selected health and fitness parameters in this cohort. Methods: Healthy young adult females aged 18-26 years (n=96), from the local community, partook in once-off tests including anthropometric measures (stature, body mass, Body Mass Index and waist circumference) as well as fitness parameters including balance, flexibility, muscular strength and endurance, and lastly lumbo-pelvic stability. Health measures investigated included blood pressure and spirometry. Where possible, results were compared to those of similar populations from national surveys or published normative data. Sedentary volunteers from this cohort were then randomised into a Pilates Exercise (PEx, n=12) or an inactive Control (Con, n=11) group, with their results from Phase 1 serving as baseline measures. Pilates classes were held twice weekly (60 minutes per session). All the measures from phase 1 were repeated at weeks 4 and 8. An additional intervention test included Transversus abdominis recruitment. Participants maintained habitual dietary intake and energy expenditure throughout. Nine PEx group and eight Con group participants completed the intervention. Results: The current sample (phase 1) was found to be healthier than comparative populations from national surveys, and significant differences (p<0.05) were found for all comparisons except Forced Expiratory Volume (FEV1), (p=0.64). Physical activity levels (230 min.week-1) exceeded that of the recommend weekly threshold (150 min.week-1). BMI, waist circumference, blood pressure and spirometry measures were all found to be within suggested healthy normal ranges. Pilates significantly improved lumbo-pelvic stability in the PEx group at weeks 4 (p<0.005) and 8 (p<0.002). Similarly, abdominal (p=0.00, d=1.1), upper limb (p=0.037, d=0.9) and lower limb endurance (p=0.02, d=1.0, between group d=0.73 for PEx) also improved with no changes in the Con group. PEx energy expenditure significantly increased from baseline to weeks 4 (p=0.007, d=10.7) and 8 (p=0.027, d=0.64), however body mass was maintained throughout. Conversely, Minute Ventilation decreased in the PEx cohort (p=0.010, d=0.95) from weeks 4 to 8. The Con group showed significant increases in body mass (p=0.018), leg strength (within-group Cohen’s d=-1.08 between weeks 0-8; d=-2 between weeks 4-8) and dynamic balance (p=0.01, d=-0.5). While no within-group changes were observed, Protein intake was significantly greater (p=0.036, d>0.8 at baseline and week 8) in the PEx group throughout the intervention. Medium between-group effect sizes (d>0.5) were noted for PEx BMI and waist circumference measures at all time points. Further, although not significant, the large within-group effect size (d=-0.84) between baseline and week 8 for PEx systolic blood pressure, suggested the 9 mm Hg was meaningful. The same time period also indicated a large within-group effect size (d=-0.8) for PEx dynamic balance, and a medium Cohen’s d for (d=0.57) PEx static balance. Conclusion: The local population of young adult females was found to be significantly healthier than those of comparable national samples. Further, Pilates participation significantly improved lumbo-pelvic stability and muscular endurance with meaningful changes in systolic blood pressure, and balance in previously sedentary young, adult females. Body mass was also maintained.
- Full Text:
- Date Issued: 2018
- Authors: Eaton, Lara Lee
- Date: 2018
- Subjects: Physical fitness for women -- South Africa -- Makhanda , Pilates method , Exercise for women -- South Africa -- Makhanda , Exercise -- Health aspects -- South Africa -- Makhanda , Exercise -- Physiological aspects -- South Africa -- Makhanda
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/58267 , vital:27112
- Description: Purpose: The first phase of this study aimed to investigate the health and fitness status of young adult females in the local community. The second phase of this study investigated the impact of an eight week progressive Pilates intervention on selected health and fitness parameters in this cohort. Methods: Healthy young adult females aged 18-26 years (n=96), from the local community, partook in once-off tests including anthropometric measures (stature, body mass, Body Mass Index and waist circumference) as well as fitness parameters including balance, flexibility, muscular strength and endurance, and lastly lumbo-pelvic stability. Health measures investigated included blood pressure and spirometry. Where possible, results were compared to those of similar populations from national surveys or published normative data. Sedentary volunteers from this cohort were then randomised into a Pilates Exercise (PEx, n=12) or an inactive Control (Con, n=11) group, with their results from Phase 1 serving as baseline measures. Pilates classes were held twice weekly (60 minutes per session). All the measures from phase 1 were repeated at weeks 4 and 8. An additional intervention test included Transversus abdominis recruitment. Participants maintained habitual dietary intake and energy expenditure throughout. Nine PEx group and eight Con group participants completed the intervention. Results: The current sample (phase 1) was found to be healthier than comparative populations from national surveys, and significant differences (p<0.05) were found for all comparisons except Forced Expiratory Volume (FEV1), (p=0.64). Physical activity levels (230 min.week-1) exceeded that of the recommend weekly threshold (150 min.week-1). BMI, waist circumference, blood pressure and spirometry measures were all found to be within suggested healthy normal ranges. Pilates significantly improved lumbo-pelvic stability in the PEx group at weeks 4 (p<0.005) and 8 (p<0.002). Similarly, abdominal (p=0.00, d=1.1), upper limb (p=0.037, d=0.9) and lower limb endurance (p=0.02, d=1.0, between group d=0.73 for PEx) also improved with no changes in the Con group. PEx energy expenditure significantly increased from baseline to weeks 4 (p=0.007, d=10.7) and 8 (p=0.027, d=0.64), however body mass was maintained throughout. Conversely, Minute Ventilation decreased in the PEx cohort (p=0.010, d=0.95) from weeks 4 to 8. The Con group showed significant increases in body mass (p=0.018), leg strength (within-group Cohen’s d=-1.08 between weeks 0-8; d=-2 between weeks 4-8) and dynamic balance (p=0.01, d=-0.5). While no within-group changes were observed, Protein intake was significantly greater (p=0.036, d>0.8 at baseline and week 8) in the PEx group throughout the intervention. Medium between-group effect sizes (d>0.5) were noted for PEx BMI and waist circumference measures at all time points. Further, although not significant, the large within-group effect size (d=-0.84) between baseline and week 8 for PEx systolic blood pressure, suggested the 9 mm Hg was meaningful. The same time period also indicated a large within-group effect size (d=-0.8) for PEx dynamic balance, and a medium Cohen’s d for (d=0.57) PEx static balance. Conclusion: The local population of young adult females was found to be significantly healthier than those of comparable national samples. Further, Pilates participation significantly improved lumbo-pelvic stability and muscular endurance with meaningful changes in systolic blood pressure, and balance in previously sedentary young, adult females. Body mass was also maintained.
- Full Text:
- Date Issued: 2018
Young adults’ perceptions of the psychosocial factors impacting upon self-disclosure online
- Authors: Edwards, Megan
- Date: 2018
- Subjects: Self-disclosure , Young adults -- psychological aspects Interpersonal relations
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/29882 , vital:30788
- Description: Online communication has become a universal phenomenon, and a significant consequence of computer mediated communication (CMC) is the influence it has on self-disclosure. The aim of the present study was to explore and describe young adults’ perceptions of online self-disclosure, specifically what young adults’ self-disclose online and what psychosocial factors impact upon self-disclosure online. Bronfenbrenner’s Bioecological Systems Theory and the Johari Window were utilised as the theoretical framework of the study. The present study utilised a qualitative approach and was exploratory and descriptive in design. The sample size of the present study was 13, and semi-structured interviews were utilised as the method of data collection. The data obtained was analysed using thematic analysis, as outlined by Braun and Clarke. Six main themes were identified, namely Types of Online Experience, Online Self-disclosure, Information Disclosed Online, Differences between Online and Offline Self-disclosure, Privacy and Online Regrets. The findings of the present study will generate a better understanding of young adults’ online self-disclosure and can be utilised for future research.
- Full Text:
- Date Issued: 2018
- Authors: Edwards, Megan
- Date: 2018
- Subjects: Self-disclosure , Young adults -- psychological aspects Interpersonal relations
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/29882 , vital:30788
- Description: Online communication has become a universal phenomenon, and a significant consequence of computer mediated communication (CMC) is the influence it has on self-disclosure. The aim of the present study was to explore and describe young adults’ perceptions of online self-disclosure, specifically what young adults’ self-disclose online and what psychosocial factors impact upon self-disclosure online. Bronfenbrenner’s Bioecological Systems Theory and the Johari Window were utilised as the theoretical framework of the study. The present study utilised a qualitative approach and was exploratory and descriptive in design. The sample size of the present study was 13, and semi-structured interviews were utilised as the method of data collection. The data obtained was analysed using thematic analysis, as outlined by Braun and Clarke. Six main themes were identified, namely Types of Online Experience, Online Self-disclosure, Information Disclosed Online, Differences between Online and Offline Self-disclosure, Privacy and Online Regrets. The findings of the present study will generate a better understanding of young adults’ online self-disclosure and can be utilised for future research.
- Full Text:
- Date Issued: 2018
Metabolic activity throughout early development of dusky kob Argyrosomus japonicus (Sciaenidae)
- Edworthy, Carla, James, Nicola C, Erasmus, B, Kemp, J O G, Kaiser, Horst, Potts, Warren M
- Authors: Edworthy, Carla , James, Nicola C , Erasmus, B , Kemp, J O G , Kaiser, Horst , Potts, Warren M
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125159 , vital:35737 , https://doi.10.2989/1814232x.2018.1441907
- Description: Metabolism quantifies the energy-consuming activities of an organism (Nelson 2016) and is used as an indication of how organisms partition energy resources to activities that allow them to survive, grow and reproduce (Post and Lee 1996). The metabolic profile, which is a composition of the various metabolic rates of an individual, therefore gives an indication of the efficiency of energy transformation and allocation (Fry 1971; Brown et al. 2004). McKenzie et al. (2016) suggested that an organism’s physiology contributes towards its ability to survive under specific environmental conditions. As a result, physiological condition can be a reflection of the performance and fitness of an organism (Pörtner 2010). When combined with information on changing environmental conditions, physiological information can provide insight into species- and community-level responses (Pörtner and Farrell 2008). These kinds of data have served numerous ecological applications, including resource management, conservation (McKenzie et al. 2016) and climate-change assessments (Pörtner and Farrell 2008).
- Full Text:
- Date Issued: 2018
- Authors: Edworthy, Carla , James, Nicola C , Erasmus, B , Kemp, J O G , Kaiser, Horst , Potts, Warren M
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125159 , vital:35737 , https://doi.10.2989/1814232x.2018.1441907
- Description: Metabolism quantifies the energy-consuming activities of an organism (Nelson 2016) and is used as an indication of how organisms partition energy resources to activities that allow them to survive, grow and reproduce (Post and Lee 1996). The metabolic profile, which is a composition of the various metabolic rates of an individual, therefore gives an indication of the efficiency of energy transformation and allocation (Fry 1971; Brown et al. 2004). McKenzie et al. (2016) suggested that an organism’s physiology contributes towards its ability to survive under specific environmental conditions. As a result, physiological condition can be a reflection of the performance and fitness of an organism (Pörtner 2010). When combined with information on changing environmental conditions, physiological information can provide insight into species- and community-level responses (Pörtner and Farrell 2008). These kinds of data have served numerous ecological applications, including resource management, conservation (McKenzie et al. 2016) and climate-change assessments (Pörtner and Farrell 2008).
- Full Text:
- Date Issued: 2018
The metabolic physiology of early stage Argyrosomus japonicus with insight into the potential effects of pCO2 induced ocean acidification
- Authors: Edworthy, Carla
- Date: 2018
- Subjects: Argyrosomus , Argyrosomus -- Growth , Argyrosomus -- Mortality , Argyrosomus -- Larvae -- Ecology , Ocean acidification , Marine ecology -- South Africa , Carbon dioxide -- Physiological effect
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/51417 , vital:26094
- Description: Ocean acidification is a phenomenon associated with global change and anthropogenic CO2 emissions that is changing the chemistry of seawater. These changes result in elevated pCO2 and reduced pH in seawater and this is impacting marine organisms in various ways. Marine fishes are considered generally tolerant to conditions of ocean acidification; however, these assumptions are based on juvenile and adult fish tolerance and the larval stages have not been frequently assessed. Furthermore, it has been suggested that temperate species, particularly those with an estuarine association, may be tolerant to variable CO2 and pH. This study used an eco-physiological approach to understand how the early life stages of Argyrosomus japonicus, an estuarine dependent marine fisheries species found in warm-temperate regions, may be impacted by ocean acidification. The metabolic response of early stage larvae (hatching to early juvenile stage) was assessed under conditions of elevated pCO2 and reduced pH in a controlled laboratory setting. Small volume static respirometry was used to determine the oxygen consumption rate of larvae raised in three pCO2 treatments including a low (pCO2 = 327.50 ± 80.07 µatm at pH 8.15), moderate (pCO2 477.40 ± 59.46 µatm at pH 8.03) and high treatment (PCO2 910.20 ± 136.45 µatm at pH 7.78). These treatment levels were relevant to the present (low) and projected conditions of ocean acidification for the years 2050 (moderate) and 2100 (high). Prior to experimentation with ocean acidification treatments, baseline metabolic rates and diurnal variation in oxygen consumption rates in early stage A. japonicus was determined. Distinct ontogenetic structuring of metabolic rates was observed in early stage A. japonicus, with no cyclical fluctuations in metabolic rate occurring during the 24 hour photoperiodic cycle. Pre-flexion larvae showed no metabolic response to ocean acidification treatments; however post-flexion stage larvae showed metabolic depression of standard metabolic rate in the moderate (32.5%) and high (9.5%) pCO2 treatments (P = 0.02). Larvae raised in the high pCO2 treatment also showed high levels of mortality with no individuals surviving past the post-flexion stage. Larvae raised in the moderate pCO2 treatment were unaffected. This study concluded that ocean acidification conditions expected for the end of the century will have significant impacts on the metabolism of early stage A. japonicus, which may result in reduced growth, retardation of skeletal development and ultimately survival as a result of increased mortality. Furthermore, the timing of reduced metabolic scope will significantly impact the recruitment ability of A. japonicus larvae into estuarine habitats. This could ultimately impact the sustainability of A. japonicus populations. Most importantly, this study highlighted the need to consider the combined effect of ontogeny and life-history strategy when assessing the vulnerability of species to ocean acidification.
- Full Text:
- Date Issued: 2018
- Authors: Edworthy, Carla
- Date: 2018
- Subjects: Argyrosomus , Argyrosomus -- Growth , Argyrosomus -- Mortality , Argyrosomus -- Larvae -- Ecology , Ocean acidification , Marine ecology -- South Africa , Carbon dioxide -- Physiological effect
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/51417 , vital:26094
- Description: Ocean acidification is a phenomenon associated with global change and anthropogenic CO2 emissions that is changing the chemistry of seawater. These changes result in elevated pCO2 and reduced pH in seawater and this is impacting marine organisms in various ways. Marine fishes are considered generally tolerant to conditions of ocean acidification; however, these assumptions are based on juvenile and adult fish tolerance and the larval stages have not been frequently assessed. Furthermore, it has been suggested that temperate species, particularly those with an estuarine association, may be tolerant to variable CO2 and pH. This study used an eco-physiological approach to understand how the early life stages of Argyrosomus japonicus, an estuarine dependent marine fisheries species found in warm-temperate regions, may be impacted by ocean acidification. The metabolic response of early stage larvae (hatching to early juvenile stage) was assessed under conditions of elevated pCO2 and reduced pH in a controlled laboratory setting. Small volume static respirometry was used to determine the oxygen consumption rate of larvae raised in three pCO2 treatments including a low (pCO2 = 327.50 ± 80.07 µatm at pH 8.15), moderate (pCO2 477.40 ± 59.46 µatm at pH 8.03) and high treatment (PCO2 910.20 ± 136.45 µatm at pH 7.78). These treatment levels were relevant to the present (low) and projected conditions of ocean acidification for the years 2050 (moderate) and 2100 (high). Prior to experimentation with ocean acidification treatments, baseline metabolic rates and diurnal variation in oxygen consumption rates in early stage A. japonicus was determined. Distinct ontogenetic structuring of metabolic rates was observed in early stage A. japonicus, with no cyclical fluctuations in metabolic rate occurring during the 24 hour photoperiodic cycle. Pre-flexion larvae showed no metabolic response to ocean acidification treatments; however post-flexion stage larvae showed metabolic depression of standard metabolic rate in the moderate (32.5%) and high (9.5%) pCO2 treatments (P = 0.02). Larvae raised in the high pCO2 treatment also showed high levels of mortality with no individuals surviving past the post-flexion stage. Larvae raised in the moderate pCO2 treatment were unaffected. This study concluded that ocean acidification conditions expected for the end of the century will have significant impacts on the metabolism of early stage A. japonicus, which may result in reduced growth, retardation of skeletal development and ultimately survival as a result of increased mortality. Furthermore, the timing of reduced metabolic scope will significantly impact the recruitment ability of A. japonicus larvae into estuarine habitats. This could ultimately impact the sustainability of A. japonicus populations. Most importantly, this study highlighted the need to consider the combined effect of ontogeny and life-history strategy when assessing the vulnerability of species to ocean acidification.
- Full Text:
- Date Issued: 2018
Parental involvement and grade 8 learners' academic achievement in mathematics : a study of selected schools in East London, South Africa
- Authors: Eesuola, Omobola Foluke
- Date: 2018
- Subjects: Education -- Parent participation -- South Africa
- Language: English
- Type: Thesis , Doctoral , Education
- Identifier: http://hdl.handle.net/10353/10497 , vital:35497
- Description: This investigation springs from the realization that academic achievement is influenced by different environmental factors. The influence of parental involvement on learners’ academic achievement has been recognized globally by experts in the education industry. As integral as parental involvement is, education industry is yet to come to terms on the best type of parental involvement needed for the teaching and learning of Mathematics in high schools especially at the transition phase. The aim of this study was to establish the relationship between parental involvement and grade 8 learners’ academic achievement in Mathematics. Quantitative research method was used for data collection. The data was collected with the use of parental involvement questionnaire for learners (PIQL) and learners Mathematics academic achievement scores. The research was conducted in six schools (public and private) within the East London Education District. The total sample size was 460 Grade 8 learners who were randomly selected across the board. The outcomes of the investigation revealed that parental involvement enhances the academic achievement of grade 8 learners irrespective of a definition of it or the measure of achievement. Furthermore, the results of this findings indicate that good parenting styles, parental support and parental educational background (r = 0.54; P < 0.05), (r =0.20; P< 0.05), (r = 0.68; P < 0.05) respectively are prerequisite for learners’ academic achievement in mathematics, showing that the variables are significantly related to learners academic achievement in mathematics; while parental involvement in the area of communication and family structure were very weak (r = 0.05; P > 0.05), (R=0.09; R2=.005; P < 0.05). This study therefore, recommended that parental involvement should be beefed up especially in areas of communication and family structure, by both the parents and teachers in order to enhance learners’ academic achievement in Mathematics.
- Full Text:
- Date Issued: 2018
- Authors: Eesuola, Omobola Foluke
- Date: 2018
- Subjects: Education -- Parent participation -- South Africa
- Language: English
- Type: Thesis , Doctoral , Education
- Identifier: http://hdl.handle.net/10353/10497 , vital:35497
- Description: This investigation springs from the realization that academic achievement is influenced by different environmental factors. The influence of parental involvement on learners’ academic achievement has been recognized globally by experts in the education industry. As integral as parental involvement is, education industry is yet to come to terms on the best type of parental involvement needed for the teaching and learning of Mathematics in high schools especially at the transition phase. The aim of this study was to establish the relationship between parental involvement and grade 8 learners’ academic achievement in Mathematics. Quantitative research method was used for data collection. The data was collected with the use of parental involvement questionnaire for learners (PIQL) and learners Mathematics academic achievement scores. The research was conducted in six schools (public and private) within the East London Education District. The total sample size was 460 Grade 8 learners who were randomly selected across the board. The outcomes of the investigation revealed that parental involvement enhances the academic achievement of grade 8 learners irrespective of a definition of it or the measure of achievement. Furthermore, the results of this findings indicate that good parenting styles, parental support and parental educational background (r = 0.54; P < 0.05), (r =0.20; P< 0.05), (r = 0.68; P < 0.05) respectively are prerequisite for learners’ academic achievement in mathematics, showing that the variables are significantly related to learners academic achievement in mathematics; while parental involvement in the area of communication and family structure were very weak (r = 0.05; P > 0.05), (R=0.09; R2=.005; P < 0.05). This study therefore, recommended that parental involvement should be beefed up especially in areas of communication and family structure, by both the parents and teachers in order to enhance learners’ academic achievement in Mathematics.
- Full Text:
- Date Issued: 2018
An investigation of the combustion kinetics of coal-microalgae composite
- Ejesieme, Obialo Vitus, Dugmore, Gary
- Authors: Ejesieme, Obialo Vitus , Dugmore, Gary
- Date: 2018
- Subjects: Microalgae -- Biotechnology , Biomass energy -- South Africa Coal -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/34777 , vital:33447
- Description: Coal mining and handling generate sizeable quantities of ultra-fine coal particles which are heaped as discard material. Use of the ultra-fine coal for co-firing with microalgae biomass appears to be a promising option that would improve combustion of the discard. There is no available traditional biomass binder that can be used to agglomerate, reclaim, and co-fire the discard ultra-fine coal to generate heat. In a recent research, microalgae biomass was identified as an effective natural binder for discard ultra-fine coal. Biomass is a renewable resource, and many have been co-fired on a large scale except microalgae biomass. Researchers have studied co-firing of dry mixed coal-microalgae, however, the kinetics of a wet mix of microalgae biomass and ultra-fine coal, “Coalgae®” patented recently by the Nelson Mandela University needs to be explored. The study aimed at investigating in some detail the oxidation mechanism of coal-microalgae composites. The objective is to understand the impact of microalgae on the kinetic properties of coal which will inform on the application of “Coalgae®”. It involves correlating the small and large-scale combustion properties that will establish the co-firing option on an industrial scenario. The goal is to utilize all grades of discard ultra-fine resource using microalgae biomass as binder and a renewable component which enhances the combustion of coal to supply heat and electricity. The use of microalgae for fuel preparation and upgrading is on the increase due to its high growth potential, reactivity, and ability to store energy more than other biomasses. This research hypothesized that blending of discard ultra-fine coal with live microalgae biomass would improve the kinetic properties of the coal more than expected from linear combination of the dry materials. Thermogravimetric combustion of “Coalgae®” was studied under non-isothermal conditions from 40 °C to 900°C at a heating rate of 15 °C/min and air flow rate of 20 ml/min. The thermogravimetric combustion properties i.e. small-scale was related to the large-scale, John Thompson’s fixed-bed reactor under the above condition. Thermal profiles were transformed into a differential function to reveal overlapped combustion events. The Coat-Redferns kinetic model was applied on the non-de-Ejesieme, O.V. PhD Chemistry (Research), Nelson Mandela Univ. Email: ejevit@yahoo.com , s211266744@live.nmmu.ac.za convoluted reactions set to obtain some of kinetic parameters. The Fraser-Suzuki equation was used to de-convolute the overlapped combustion. Then, rate law combined with Arrhenius equation was used to derive the activation energy E a and pre-exponential factor A, while the integral form of solid states reaction model, g (∝) was applied to deduce the oxidation mechanism. The composite formed a strong and partly renewable blend under controlled temperature conditions, unlike assorted dried biomass mixed with coal. Microalgae biomass upgraded the fuel and kinetics properties of ultra-fine coal more than what was expected from a linear combination. It released heat that promoted the oxidation mechanism of the discard coal. The main effect is that the “Coalgae®” is significantly (p = 0.0570) more reactive than the coal. The co-firing approach is partly renewable and contributes to the utilization of high and low-quality available discard ultra-fine coal. It advances the combustion of coal resources and reduces carbon dioxide, CO2 emission attributed to global warming as well as preserves the natural biomass sources. The combustion of “Coalgae® “will improve economy, environment, and health, heat, and electricity supply to the society.
- Full Text:
- Date Issued: 2018
- Authors: Ejesieme, Obialo Vitus , Dugmore, Gary
- Date: 2018
- Subjects: Microalgae -- Biotechnology , Biomass energy -- South Africa Coal -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/34777 , vital:33447
- Description: Coal mining and handling generate sizeable quantities of ultra-fine coal particles which are heaped as discard material. Use of the ultra-fine coal for co-firing with microalgae biomass appears to be a promising option that would improve combustion of the discard. There is no available traditional biomass binder that can be used to agglomerate, reclaim, and co-fire the discard ultra-fine coal to generate heat. In a recent research, microalgae biomass was identified as an effective natural binder for discard ultra-fine coal. Biomass is a renewable resource, and many have been co-fired on a large scale except microalgae biomass. Researchers have studied co-firing of dry mixed coal-microalgae, however, the kinetics of a wet mix of microalgae biomass and ultra-fine coal, “Coalgae®” patented recently by the Nelson Mandela University needs to be explored. The study aimed at investigating in some detail the oxidation mechanism of coal-microalgae composites. The objective is to understand the impact of microalgae on the kinetic properties of coal which will inform on the application of “Coalgae®”. It involves correlating the small and large-scale combustion properties that will establish the co-firing option on an industrial scenario. The goal is to utilize all grades of discard ultra-fine resource using microalgae biomass as binder and a renewable component which enhances the combustion of coal to supply heat and electricity. The use of microalgae for fuel preparation and upgrading is on the increase due to its high growth potential, reactivity, and ability to store energy more than other biomasses. This research hypothesized that blending of discard ultra-fine coal with live microalgae biomass would improve the kinetic properties of the coal more than expected from linear combination of the dry materials. Thermogravimetric combustion of “Coalgae®” was studied under non-isothermal conditions from 40 °C to 900°C at a heating rate of 15 °C/min and air flow rate of 20 ml/min. The thermogravimetric combustion properties i.e. small-scale was related to the large-scale, John Thompson’s fixed-bed reactor under the above condition. Thermal profiles were transformed into a differential function to reveal overlapped combustion events. The Coat-Redferns kinetic model was applied on the non-de-Ejesieme, O.V. PhD Chemistry (Research), Nelson Mandela Univ. Email: ejevit@yahoo.com , s211266744@live.nmmu.ac.za convoluted reactions set to obtain some of kinetic parameters. The Fraser-Suzuki equation was used to de-convolute the overlapped combustion. Then, rate law combined with Arrhenius equation was used to derive the activation energy E a and pre-exponential factor A, while the integral form of solid states reaction model, g (∝) was applied to deduce the oxidation mechanism. The composite formed a strong and partly renewable blend under controlled temperature conditions, unlike assorted dried biomass mixed with coal. Microalgae biomass upgraded the fuel and kinetics properties of ultra-fine coal more than what was expected from a linear combination. It released heat that promoted the oxidation mechanism of the discard coal. The main effect is that the “Coalgae®” is significantly (p = 0.0570) more reactive than the coal. The co-firing approach is partly renewable and contributes to the utilization of high and low-quality available discard ultra-fine coal. It advances the combustion of coal resources and reduces carbon dioxide, CO2 emission attributed to global warming as well as preserves the natural biomass sources. The combustion of “Coalgae® “will improve economy, environment, and health, heat, and electricity supply to the society.
- Full Text:
- Date Issued: 2018
Legitimation of knowers for access in science
- Authors: Ellery, Karen
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70302 , vital:29643 , https://doi.org/10.1080/02602930701772788
- Description: Based on poor performance of students in the higher education science context, this paper questions the current focus on content knowledge and, in so doing, examines the role student knowers play in enabling epistemological access. Using Legitimation Code Theory, and drawing on data from interviews, course documents, observations, and critical reflections, the social relations of a science foundation course in the South African context are examined empirically to reveal the valuing of two kinds of knowers—learning-context knowers (or science learners) and production-context knowers (or scientists). Since being both kinds of knowers is necessary for access to powerful science knowledge, and home and educational contexts of certain groups of students are better in terms of enabling science knowers and learners than others, it is argued from a social justice perspective that science (and other) curricula account for knower attributes in enabling access for success for all students.
- Full Text:
- Date Issued: 2018
- Authors: Ellery, Karen
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70302 , vital:29643 , https://doi.org/10.1080/02602930701772788
- Description: Based on poor performance of students in the higher education science context, this paper questions the current focus on content knowledge and, in so doing, examines the role student knowers play in enabling epistemological access. Using Legitimation Code Theory, and drawing on data from interviews, course documents, observations, and critical reflections, the social relations of a science foundation course in the South African context are examined empirically to reveal the valuing of two kinds of knowers—learning-context knowers (or science learners) and production-context knowers (or scientists). Since being both kinds of knowers is necessary for access to powerful science knowledge, and home and educational contexts of certain groups of students are better in terms of enabling science knowers and learners than others, it is argued from a social justice perspective that science (and other) curricula account for knower attributes in enabling access for success for all students.
- Full Text:
- Date Issued: 2018
Aquatic habitat shift assessment in a groundwater-fed semi-arid stream: an investigation into the response of Karoo hydroecology to system variability
- Authors: Ellis, Natalie
- Date: 2018
- Subjects: Aquatic habitats -- South Africa -- Karoo , Arid regions -- South Africa -- Karoo , Biotic communities -- South Africa -- Karoo , Stream ecology -- South Africa -- Karoo
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/61882 , vital:28072
- Description: From introduction: The subject of biological response to changes in aquatic habitat is one which has been well explored in many regions of the world. Examples include work in south east Spain by Mellado Diaz et al. (2008) and Oliva-Paterna et al. (2003), in western United States of America by Hauer and Lorang (2004), and in West Germany by Meyer et al. (2003). Similarly, a number of studies have been conducted in semi-arid regions, exploring elements such as erosion, climate, lithology and landscape formations (e.g. Boardman et al., 2013; Le Maitre et al., 2007; Meyer et al., 2003). However, apart from the study by Uys (1997), and Uys and O’Keeffe (1997), there is a noticeable lack of literature on aquatic habitat shifts in semi-arid stream systems, despite these systems being recognised for their high natural variability. This study provides a base-level approach to conducting habitat shift assessments in a semi-arid stream system and monitoring the hydroecological responses to system variability.
- Full Text:
- Date Issued: 2018
- Authors: Ellis, Natalie
- Date: 2018
- Subjects: Aquatic habitats -- South Africa -- Karoo , Arid regions -- South Africa -- Karoo , Biotic communities -- South Africa -- Karoo , Stream ecology -- South Africa -- Karoo
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/61882 , vital:28072
- Description: From introduction: The subject of biological response to changes in aquatic habitat is one which has been well explored in many regions of the world. Examples include work in south east Spain by Mellado Diaz et al. (2008) and Oliva-Paterna et al. (2003), in western United States of America by Hauer and Lorang (2004), and in West Germany by Meyer et al. (2003). Similarly, a number of studies have been conducted in semi-arid regions, exploring elements such as erosion, climate, lithology and landscape formations (e.g. Boardman et al., 2013; Le Maitre et al., 2007; Meyer et al., 2003). However, apart from the study by Uys (1997), and Uys and O’Keeffe (1997), there is a noticeable lack of literature on aquatic habitat shifts in semi-arid stream systems, despite these systems being recognised for their high natural variability. This study provides a base-level approach to conducting habitat shift assessments in a semi-arid stream system and monitoring the hydroecological responses to system variability.
- Full Text:
- Date Issued: 2018
Grapple cable yarding: a productivity model for fast-growing tree plantations in Sarawak, Malaysia
- Authors: Engelbrecht, Riaan
- Date: 2018
- Subjects: Tree farms -- Malaysia -- Sarawak , Forests and forestry -- Malaysia -- Sarawak Forest productivity -- Malaysia -- Sarawak
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/22049 , vital:29816
- Description: Today, the two most important tasks faced by harvesting foresters and contractors are selecting the equipment and systems best suited to the site, and then to use this equipment in the best way possible (MacDonald, 1999). Experts estimate that the importance of tree plantations will continue to grow and that by 2050 75 per cent of the global fibre supply will be sourced from dedicated plantations (Ragauskas et al., 2006). To meet this growing demand plantations will most likely expand to steep slopes due to the priority given to agricultural and urban development, on flat land. New technological advancements in both cable yarding and ground-based harvesting systems has to a certain extent provided forest engineers with more options to choose from. Whether considering these options individually or in combination, they will have to make good choices in order to realise the full potential of forest plantations. One of the most promising techniques consist of an excavator-based unguyed yarder equipped with a new radio-controlled grapple carriage, fed by another excavator stationed on the cut-over. This system is very productive, avoids in-stand traffic and removes operators from positions of high risk. This long-term study was conducted on 12 different teams equipped with the new technology, operating in the fast-growing Acacia mangium plantations of Sarawak, Malaysia. Data were collected continuously for almost 8 months and represented 555 shifts, or over 55,000 yarding cycles - each recorded individually. This large data pool allowed for the development of robust models for system production, utilization and availability estimated respectively at: 63 m3 per productive machine hour (excluding all delays), 63 per cent and 93 per cent. The study also determined the effects of yarder type and team competence on productivity and utilization. Regression analysis of experimental data yielded a strong productivity forecast model that was highly significant, which accounted for 50 per cent of the total variability in the dataset and was validated with a non-significant error estimated at less than 1 per cent. The models reported in this study are especially robust, because they were obtained from a long-term study that covered multiple teams and accumulated an exceptionally large number of observations. While gained specifically on one yarder make (Alpine Yarder) and a specific plantation type (Acacia mangium), the information in this study can be extended to other similar machines and plantations, because the sheer volume of data allows cautious generalization. The teachings of kaizen, which suggest small-step work improvements, was adopted in order to propose the process of possible improvements, by combining elements of other harvesting systems as shown in Figure 1 below (Vorn Industries, 2017). Forestry is essentially a problem of transportation (Schenck, 1911) and the efficiency of such a transportation system will ultimately be determined by technology developments which drive system productivity (Ger & Klvac, 2014). Therefore, when we talk about systems for the future we should view them not as predictions or as prescriptions but as options that may be selected or rejected (Wood, 1979).
- Full Text:
- Date Issued: 2018
- Authors: Engelbrecht, Riaan
- Date: 2018
- Subjects: Tree farms -- Malaysia -- Sarawak , Forests and forestry -- Malaysia -- Sarawak Forest productivity -- Malaysia -- Sarawak
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/22049 , vital:29816
- Description: Today, the two most important tasks faced by harvesting foresters and contractors are selecting the equipment and systems best suited to the site, and then to use this equipment in the best way possible (MacDonald, 1999). Experts estimate that the importance of tree plantations will continue to grow and that by 2050 75 per cent of the global fibre supply will be sourced from dedicated plantations (Ragauskas et al., 2006). To meet this growing demand plantations will most likely expand to steep slopes due to the priority given to agricultural and urban development, on flat land. New technological advancements in both cable yarding and ground-based harvesting systems has to a certain extent provided forest engineers with more options to choose from. Whether considering these options individually or in combination, they will have to make good choices in order to realise the full potential of forest plantations. One of the most promising techniques consist of an excavator-based unguyed yarder equipped with a new radio-controlled grapple carriage, fed by another excavator stationed on the cut-over. This system is very productive, avoids in-stand traffic and removes operators from positions of high risk. This long-term study was conducted on 12 different teams equipped with the new technology, operating in the fast-growing Acacia mangium plantations of Sarawak, Malaysia. Data were collected continuously for almost 8 months and represented 555 shifts, or over 55,000 yarding cycles - each recorded individually. This large data pool allowed for the development of robust models for system production, utilization and availability estimated respectively at: 63 m3 per productive machine hour (excluding all delays), 63 per cent and 93 per cent. The study also determined the effects of yarder type and team competence on productivity and utilization. Regression analysis of experimental data yielded a strong productivity forecast model that was highly significant, which accounted for 50 per cent of the total variability in the dataset and was validated with a non-significant error estimated at less than 1 per cent. The models reported in this study are especially robust, because they were obtained from a long-term study that covered multiple teams and accumulated an exceptionally large number of observations. While gained specifically on one yarder make (Alpine Yarder) and a specific plantation type (Acacia mangium), the information in this study can be extended to other similar machines and plantations, because the sheer volume of data allows cautious generalization. The teachings of kaizen, which suggest small-step work improvements, was adopted in order to propose the process of possible improvements, by combining elements of other harvesting systems as shown in Figure 1 below (Vorn Industries, 2017). Forestry is essentially a problem of transportation (Schenck, 1911) and the efficiency of such a transportation system will ultimately be determined by technology developments which drive system productivity (Ger & Klvac, 2014). Therefore, when we talk about systems for the future we should view them not as predictions or as prescriptions but as options that may be selected or rejected (Wood, 1979).
- Full Text:
- Date Issued: 2018
Variation in perception of environmental change in nine Solomon Islands communities: implications for securing fairness in community-based adaptation
- Ensor, Jonathan Edward, Abernethy, Kirsten Elizabeth, Hoddy, Eric Timothy, Aswani, Shankar, Albert, Simon, Vaccaro, Ismael, Benedict, Jason Jon, Beare, Douglas James
- Authors: Ensor, Jonathan Edward , Abernethy, Kirsten Elizabeth , Hoddy, Eric Timothy , Aswani, Shankar , Albert, Simon , Vaccaro, Ismael , Benedict, Jason Jon , Beare, Douglas James
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145380 , vital:38433 , DOI: 10.1007/s10113-017-1242-1
- Description: Community-based approaches are pursued in recognition of the need for place-based responses to environmental change that integrate local understandings of risk and vulnerability. Yet the potential for fair adaptation is intimately linked to how variations in perceptions of environmental change and risk are treated. There is, however, little empirical evidence of the extent and nature of variations in risk perception in and between multiple community settings. Here, we rely on data from 231 semi-structured interviews conducted in nine communities in Western Province, Solomon Islands, to statistically model different perceptions of risk and change within and between communities.
- Full Text:
- Date Issued: 2018
- Authors: Ensor, Jonathan Edward , Abernethy, Kirsten Elizabeth , Hoddy, Eric Timothy , Aswani, Shankar , Albert, Simon , Vaccaro, Ismael , Benedict, Jason Jon , Beare, Douglas James
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145380 , vital:38433 , DOI: 10.1007/s10113-017-1242-1
- Description: Community-based approaches are pursued in recognition of the need for place-based responses to environmental change that integrate local understandings of risk and vulnerability. Yet the potential for fair adaptation is intimately linked to how variations in perceptions of environmental change and risk are treated. There is, however, little empirical evidence of the extent and nature of variations in risk perception in and between multiple community settings. Here, we rely on data from 231 semi-structured interviews conducted in nine communities in Western Province, Solomon Islands, to statistically model different perceptions of risk and change within and between communities.
- Full Text:
- Date Issued: 2018
Effects of CO2-induced ocean acidification on the early development, growth, survival and skeletogenesis of the estuarine-dependant sciaenid Argyrosomus japonicus
- Authors: Erasmus, Bernard
- Date: 2018
- Subjects: Argyrosomus , Argyrosomus -- Growth , Argyrosomus -- Mortality , Argyrosomus -- Ecology , Argyrosomus -- Physiology , Ocean acidification , Marine ecology -- South Africa , Carbon dioxide -- Physiological effect
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/60585 , vital:27799
- Description: Although it is increasingly accepted that ocean acidification poses a considerable threat to marine organisms, little is known about the likely response of fishes to this phenomenon. While initial research concluded that adult fishes may be tolerant to changes predicted in the next 300 years, the response of early life stages to end-of-century CO2 levels (~ 1100 µatm according to the IPCC RCP 8.5) remains unclear. To date, literature on the early growth and survival of fishes has yielded conflicting results, suggesting that vulnerability may be species dependant. The paucity of ocean acidification research on fishes is particularly evident when one considers larval skeletogenesis, with no robust studies on its impacts on bone and cartilage development. This study addresses the early life embryogenesis, hatching success, growth, skeletogenesis and survival of an estuarine-dependant species. Dusky kob (Argyrosomus japonicus) were reared in a control (pCO2 = 327.50 ± 80.07 qatm at pH 8.15), intermediate (pCO2 477.40 ± 59.46 qatm at pH 8.03) and high pCO2 treatment (pCO2 910.20 ± 136.45 qatm at pH 7.78) from egg to 29 days post-hatch (dph). Sixty individuals from each treatment were sacrificed at the egg stage and at 2, 6, 13, 18, 21 and 26 dph, measured and stained using an acid-free double- staining solution to prevent the deterioration of calcified matrices in fragile larval skeletons. The proportion of bone and cartilage was quantified at each stage using a novel pixel-counting method. Growth and skeletal development were identical between treatments until the onset of metamorphosis (21 dph). However, from the metamorphosis stage, the growth and skeletal development rate was significantly faster in the intermediate treatment and significantly slower in the high treatment when compared to the control treatment. By 26 dph, A. japonicus reared in high pCO2 were, on average, 47.2% smaller than the control treatment, and the relative proportion of bone in the body was 45.3% lower in the high pCO2 treatment when compared with the control. In addition, none of the fish in the high pCO2 treatment survived after 26 dph. It appears that the combination of the increased energy requirements during metamorphosis and the increased energy cost associated with acid-base regulation may account for reduced growth, skeletogenesis and poor survival in high pCO2. Regardless of the driver, the results of this study suggest that the pCO2 levels predicted for the end of the century may have negative effects on the growth, skeletal development, and survival during metamorphosis.
- Full Text:
- Date Issued: 2018
- Authors: Erasmus, Bernard
- Date: 2018
- Subjects: Argyrosomus , Argyrosomus -- Growth , Argyrosomus -- Mortality , Argyrosomus -- Ecology , Argyrosomus -- Physiology , Ocean acidification , Marine ecology -- South Africa , Carbon dioxide -- Physiological effect
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/60585 , vital:27799
- Description: Although it is increasingly accepted that ocean acidification poses a considerable threat to marine organisms, little is known about the likely response of fishes to this phenomenon. While initial research concluded that adult fishes may be tolerant to changes predicted in the next 300 years, the response of early life stages to end-of-century CO2 levels (~ 1100 µatm according to the IPCC RCP 8.5) remains unclear. To date, literature on the early growth and survival of fishes has yielded conflicting results, suggesting that vulnerability may be species dependant. The paucity of ocean acidification research on fishes is particularly evident when one considers larval skeletogenesis, with no robust studies on its impacts on bone and cartilage development. This study addresses the early life embryogenesis, hatching success, growth, skeletogenesis and survival of an estuarine-dependant species. Dusky kob (Argyrosomus japonicus) were reared in a control (pCO2 = 327.50 ± 80.07 qatm at pH 8.15), intermediate (pCO2 477.40 ± 59.46 qatm at pH 8.03) and high pCO2 treatment (pCO2 910.20 ± 136.45 qatm at pH 7.78) from egg to 29 days post-hatch (dph). Sixty individuals from each treatment were sacrificed at the egg stage and at 2, 6, 13, 18, 21 and 26 dph, measured and stained using an acid-free double- staining solution to prevent the deterioration of calcified matrices in fragile larval skeletons. The proportion of bone and cartilage was quantified at each stage using a novel pixel-counting method. Growth and skeletal development were identical between treatments until the onset of metamorphosis (21 dph). However, from the metamorphosis stage, the growth and skeletal development rate was significantly faster in the intermediate treatment and significantly slower in the high treatment when compared to the control treatment. By 26 dph, A. japonicus reared in high pCO2 were, on average, 47.2% smaller than the control treatment, and the relative proportion of bone in the body was 45.3% lower in the high pCO2 treatment when compared with the control. In addition, none of the fish in the high pCO2 treatment survived after 26 dph. It appears that the combination of the increased energy requirements during metamorphosis and the increased energy cost associated with acid-base regulation may account for reduced growth, skeletogenesis and poor survival in high pCO2. Regardless of the driver, the results of this study suggest that the pCO2 levels predicted for the end of the century may have negative effects on the growth, skeletal development, and survival during metamorphosis.
- Full Text:
- Date Issued: 2018
Challenging Biblical boundaries: Jeanette Winterson’s postmodern feminist subversion of Biblical discourse in Oranges are not the only fruit (1985) and Boating for beginners (1985)
- Authors: Erasmus, Shirley
- Date: 2018
- Subjects: Winterson, Jeanette, 1959- -- Criticism and interpretation , Bible -- Feminist criticism , Bible -- Criticism, interpretation, etc , Postmodernism -- Religious aspects , Winterson, Jeanette, 1959- -- Oranges are not the only fruit , Winterson, Jeanette, 1959- -- Boating for beginners , Patriarchy in literature , Sex discrimination in literature
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/59121 , vital:27430
- Description: This thesis investigates the subversion of Biblical discourse in Jeanette Winterson’s first two novels, Oranges are Not the Only Fruit and Boating for Beginners. By rewriting Biblical stories Winterson challenges traditional Western religious discourses and their rules for heteronormative social and sexual behaviours and desires. Winterson’s texts respond to the patriarchal nature of socially pervasive texts, such as the Bible, by encouraging her readers to regard these texts with suspicion, thus highlighting what can be seen as a ‘postmodern concern’ with the notion of ‘truth’. Chapter One of this thesis comprises a discussion of Biblical boundaries. These boundaries, I argue, are a process of historical oppression which serves to subjugate and control women, a practice inherent in the Bible and modern society. The Biblical boundaries within which women are expected to live, are carefully portrayed in Oranges and then comically and blasphemously mocked in Boating. Chapter One also argues that Winterson’s sexuality plays an important role in the understanding of her texts, despite her desire for her sexuality to remain ‘outside’ her writing. Chapter Two of this thesis, examines the mix of fact and fiction in Oranges, in order to create a new genre: fictional memoir. The chapter introduces the concept of the ‘autobiographical pact’ and the textual agreement which Winterson creates with her readers. In this chapter, I examine Winterson’s powerful subversion of Biblical discourse, through her narration of Jeanette’s ‘coming out’ within a Biblical framework. Chapter Three of this thesis examines Winterson’s second book, Boating, and the serious elements of this comic book. This chapter studies the various postmodern narrative techniques used in Boating in order to subvert Biblical and historical discourse. Chapter Three highlights Winterson’s postmodern concern with the construction of history as ‘truth’. Finally, Chapter Four compares Oranges and Boating, showing the texts as differing, yet equally relevant textual counterparts. This chapter examines the anti-feminine characters in both texts and Winterson’s ability to align her reader with a feminist or lesbian viewpoint. This thesis argues that Winterson’s first two texts deliberately challenge Biblical discourse in favour of a postmodern feminist viewpoint.
- Full Text:
- Date Issued: 2018
- Authors: Erasmus, Shirley
- Date: 2018
- Subjects: Winterson, Jeanette, 1959- -- Criticism and interpretation , Bible -- Feminist criticism , Bible -- Criticism, interpretation, etc , Postmodernism -- Religious aspects , Winterson, Jeanette, 1959- -- Oranges are not the only fruit , Winterson, Jeanette, 1959- -- Boating for beginners , Patriarchy in literature , Sex discrimination in literature
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/59121 , vital:27430
- Description: This thesis investigates the subversion of Biblical discourse in Jeanette Winterson’s first two novels, Oranges are Not the Only Fruit and Boating for Beginners. By rewriting Biblical stories Winterson challenges traditional Western religious discourses and their rules for heteronormative social and sexual behaviours and desires. Winterson’s texts respond to the patriarchal nature of socially pervasive texts, such as the Bible, by encouraging her readers to regard these texts with suspicion, thus highlighting what can be seen as a ‘postmodern concern’ with the notion of ‘truth’. Chapter One of this thesis comprises a discussion of Biblical boundaries. These boundaries, I argue, are a process of historical oppression which serves to subjugate and control women, a practice inherent in the Bible and modern society. The Biblical boundaries within which women are expected to live, are carefully portrayed in Oranges and then comically and blasphemously mocked in Boating. Chapter One also argues that Winterson’s sexuality plays an important role in the understanding of her texts, despite her desire for her sexuality to remain ‘outside’ her writing. Chapter Two of this thesis, examines the mix of fact and fiction in Oranges, in order to create a new genre: fictional memoir. The chapter introduces the concept of the ‘autobiographical pact’ and the textual agreement which Winterson creates with her readers. In this chapter, I examine Winterson’s powerful subversion of Biblical discourse, through her narration of Jeanette’s ‘coming out’ within a Biblical framework. Chapter Three of this thesis examines Winterson’s second book, Boating, and the serious elements of this comic book. This chapter studies the various postmodern narrative techniques used in Boating in order to subvert Biblical and historical discourse. Chapter Three highlights Winterson’s postmodern concern with the construction of history as ‘truth’. Finally, Chapter Four compares Oranges and Boating, showing the texts as differing, yet equally relevant textual counterparts. This chapter examines the anti-feminine characters in both texts and Winterson’s ability to align her reader with a feminist or lesbian viewpoint. This thesis argues that Winterson’s first two texts deliberately challenge Biblical discourse in favour of a postmodern feminist viewpoint.
- Full Text:
- Date Issued: 2018