On the optical characterization of photovoltaic devices
- Authors: Gxasheka, Andile Richman
- Date: 2008
- Subjects: Photovoltaic power systems -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10529 , http://hdl.handle.net/10948/692 , Photovoltaic power systems -- South Africa
- Description: Semiconductor materials used for making photovoltaic (PV) cells have defects and impurities due to constraints of keeping production costs low. Electrically active defects that are distributed over the bulk material lead to reduced overall performance of a photovoltaic (PV) cell. In this study an adaptable Light Beam Induced Current (LBIC) system was designed in order to characterize the local performance of PV cells. The system uses a laser source and objective lens mounted vertically above the sample on the X-Y stage. Two current pre-amplifiers are used for converting the photo-generated current from the PV cell and the signal from the reflection detector cell into a voltage that can be measured by the data acquisition board. Two configurations for measuring the photo-current maps of either bare cells or encapsulated PV mini-modules can be used. To add flexibility it was envisaged that the system would be built in such a way that it allows easy integration of carrier lifetime mapping capabilities while keeping costs to a minimum. The carrier lifetime measurement technique integrated into the LBIC system is based on the optical Open-Circuit Voltage-Decay (OCVD) method. In a single-crystalline silicon PV cell that was tested, photo-current and opencircuit voltage LBIC scans revealed shunting behaviour due to scratch marks on the front surface. The marks are believed to have been caused by poor handling during manufacturing process. Reduced photo-current due to edge shunting was observed towards the edges of the PV cell. In another sample of single crystalline silicon cell an edge shunt resulted in a 30 percent drop in photo-current measured. LBIC measurements performed on multi-crystalline cells revealed nonuniformities such as enhanced photo-current on one side of grain boundaries. These asymmetric enhancements of local photo-current are attributed to the incline of the grain boundary into the bulk of the material. LBIC results obtained from mini modules showed a high degree of mismatching from cell to cell. It is well known that mismatching can degrade the performance of a PV module with series connected cells. The LBIC measurements presented also illustrated the negative effects of delamination on the photo-current of PV modules. The LBIC measurements performed on mini PV modules highlight some of the benefits of using an LBIC technique as a tool for investigating PV cell’s local photo-current response. The effective lifetime maps obtained highlight the importance of optical OCVD method as a tool that can be used in conjunction with conventional LBIC technique. Effective minority carrier lifetimes around 40 ms were measured on a single crystalline silicon cell of 2.5 x 2.5 cm2. Local features such as cracks and lifetime degrading defects were revealed by LBIC maps and were also confirmed on effective lifetime maps. The results presented demonstrate the importance of using effective carrier lifetime maps to complement photocurrent maps of PV cells and identification of areas where defects are located.
- Full Text:
- Date Issued: 2008
- Authors: Gxasheka, Andile Richman
- Date: 2008
- Subjects: Photovoltaic power systems -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10529 , http://hdl.handle.net/10948/692 , Photovoltaic power systems -- South Africa
- Description: Semiconductor materials used for making photovoltaic (PV) cells have defects and impurities due to constraints of keeping production costs low. Electrically active defects that are distributed over the bulk material lead to reduced overall performance of a photovoltaic (PV) cell. In this study an adaptable Light Beam Induced Current (LBIC) system was designed in order to characterize the local performance of PV cells. The system uses a laser source and objective lens mounted vertically above the sample on the X-Y stage. Two current pre-amplifiers are used for converting the photo-generated current from the PV cell and the signal from the reflection detector cell into a voltage that can be measured by the data acquisition board. Two configurations for measuring the photo-current maps of either bare cells or encapsulated PV mini-modules can be used. To add flexibility it was envisaged that the system would be built in such a way that it allows easy integration of carrier lifetime mapping capabilities while keeping costs to a minimum. The carrier lifetime measurement technique integrated into the LBIC system is based on the optical Open-Circuit Voltage-Decay (OCVD) method. In a single-crystalline silicon PV cell that was tested, photo-current and opencircuit voltage LBIC scans revealed shunting behaviour due to scratch marks on the front surface. The marks are believed to have been caused by poor handling during manufacturing process. Reduced photo-current due to edge shunting was observed towards the edges of the PV cell. In another sample of single crystalline silicon cell an edge shunt resulted in a 30 percent drop in photo-current measured. LBIC measurements performed on multi-crystalline cells revealed nonuniformities such as enhanced photo-current on one side of grain boundaries. These asymmetric enhancements of local photo-current are attributed to the incline of the grain boundary into the bulk of the material. LBIC results obtained from mini modules showed a high degree of mismatching from cell to cell. It is well known that mismatching can degrade the performance of a PV module with series connected cells. The LBIC measurements presented also illustrated the negative effects of delamination on the photo-current of PV modules. The LBIC measurements performed on mini PV modules highlight some of the benefits of using an LBIC technique as a tool for investigating PV cell’s local photo-current response. The effective lifetime maps obtained highlight the importance of optical OCVD method as a tool that can be used in conjunction with conventional LBIC technique. Effective minority carrier lifetimes around 40 ms were measured on a single crystalline silicon cell of 2.5 x 2.5 cm2. Local features such as cracks and lifetime degrading defects were revealed by LBIC maps and were also confirmed on effective lifetime maps. The results presented demonstrate the importance of using effective carrier lifetime maps to complement photocurrent maps of PV cells and identification of areas where defects are located.
- Full Text:
- Date Issued: 2008
On the Processing of InAsSb/GaSb photodiodes for infrared detection
- Authors: Odendaal, Vicky
- Date: 2008
- Subjects: Gallium arsenide semiconductors , Photovoltaic cells , Infrared detectors , Gas-detectors
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10523 , http://hdl.handle.net/10948/980 , Gallium arsenide semiconductors , Photovoltaic cells , Infrared detectors , Gas-detectors
- Description: The objective of this dissertation is the development of the necessary processing steps needed to manufacture infrared photodiodes on InAs1-xSbx material. Preliminary surface preparation steps were performed on both InAs and InSb material, thus covering both possible extremes of the antimony mole fraction. The first experiments endeavoured to characterise the effect of several possible etchants with regards to etch rate, repeatability, limitations for photolithographic patterning and the resultant surface roughness. The etchants investigated include a lactic acid based etchant, a sulphuric acid based etchant, an acetic acid based etchant, an ammonium based etchant, a hydrochloric acid based etchant as well as an organic rinse procedure. These cleaning and etching steps were evaluated at several temperatures. Measurements were performed on an Alpha Step stylus profiler as well as an atomic force microscope. Metal-insulator-semiconductor capacitor devices were manufactured, on both InAs and InSb material, in order to investigate the effects of the above-mentioned etchants combined with surface passivation techniques in terms of surface state densities. Capacitance-versus-bias voltage measurements were done to determine the resultant surface state densities and to compare these to the surface state density of an untreated reference sample. The surface passivation techniques included KOH, Na2S as well as (NH4)2S anodisation. Auger electron spectroscopy measurements were done on InAs and InSb material in order to examine possible surface contamination due to the etchants as well as combinations of these etching and anodisation procedures. The extent of surface coverage by contaminants as well as by the intrinsic elements was measured. The results of the cleaning and etching as well as the surface passivation studies were used to manufacture photovoltaic infrared diodes on an MOCVD (metal oxide chemical vapour deposition) grown p-InAs0.91Sb0.09/i- InAs0.91Sb0.09/n-GaSb structure. Current-versus-voltage and electro-optical measurements were performed on the these diodes in order to evaluate the effect of sulphuric acid based etching combined with KOH, Na2S or (NH4)2S anodisation on the detector performance. The results of surface passivated structures were compared to those of an unpassivated reference detector.
- Full Text:
- Date Issued: 2008
- Authors: Odendaal, Vicky
- Date: 2008
- Subjects: Gallium arsenide semiconductors , Photovoltaic cells , Infrared detectors , Gas-detectors
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10523 , http://hdl.handle.net/10948/980 , Gallium arsenide semiconductors , Photovoltaic cells , Infrared detectors , Gas-detectors
- Description: The objective of this dissertation is the development of the necessary processing steps needed to manufacture infrared photodiodes on InAs1-xSbx material. Preliminary surface preparation steps were performed on both InAs and InSb material, thus covering both possible extremes of the antimony mole fraction. The first experiments endeavoured to characterise the effect of several possible etchants with regards to etch rate, repeatability, limitations for photolithographic patterning and the resultant surface roughness. The etchants investigated include a lactic acid based etchant, a sulphuric acid based etchant, an acetic acid based etchant, an ammonium based etchant, a hydrochloric acid based etchant as well as an organic rinse procedure. These cleaning and etching steps were evaluated at several temperatures. Measurements were performed on an Alpha Step stylus profiler as well as an atomic force microscope. Metal-insulator-semiconductor capacitor devices were manufactured, on both InAs and InSb material, in order to investigate the effects of the above-mentioned etchants combined with surface passivation techniques in terms of surface state densities. Capacitance-versus-bias voltage measurements were done to determine the resultant surface state densities and to compare these to the surface state density of an untreated reference sample. The surface passivation techniques included KOH, Na2S as well as (NH4)2S anodisation. Auger electron spectroscopy measurements were done on InAs and InSb material in order to examine possible surface contamination due to the etchants as well as combinations of these etching and anodisation procedures. The extent of surface coverage by contaminants as well as by the intrinsic elements was measured. The results of the cleaning and etching as well as the surface passivation studies were used to manufacture photovoltaic infrared diodes on an MOCVD (metal oxide chemical vapour deposition) grown p-InAs0.91Sb0.09/i- InAs0.91Sb0.09/n-GaSb structure. Current-versus-voltage and electro-optical measurements were performed on the these diodes in order to evaluate the effect of sulphuric acid based etching combined with KOH, Na2S or (NH4)2S anodisation on the detector performance. The results of surface passivated structures were compared to those of an unpassivated reference detector.
- Full Text:
- Date Issued: 2008
Perceptions on future fulfilment of visually impaired adolescent learners at the Khanyisa Special School
- Authors: Ciyana, Nontobeko Minica
- Date: 2008
- Subjects: Blind children -- Education -- South Africa -- Port Elizabeth , Children with visual disabilities -- Education -- South Africa -- Port Elizabeth , Special education -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9538 , http://hdl.handle.net/10948/683 , Blind children -- Education -- South Africa -- Port Elizabeth , Children with visual disabilities -- Education -- South Africa -- Port Elizabeth , Special education -- South Africa -- Port Elizabeth
- Description: This research focuses on the perceptions of future fulfilment of visually impaired adolescent learners at the Khanyisa Special School. The qualitative research was undertaken at the selected special school, which is situated in Nelson Mandela Bay in the western region of the Eastern Cape Province of South Africa, with ten learners, ten parents and five teachers as participants. The concluding chapter suggests ways and recommendations to assist the visually impaired adolescent learners at the Khanyisa Special School financially and academically.
- Full Text:
- Date Issued: 2008
- Authors: Ciyana, Nontobeko Minica
- Date: 2008
- Subjects: Blind children -- Education -- South Africa -- Port Elizabeth , Children with visual disabilities -- Education -- South Africa -- Port Elizabeth , Special education -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9538 , http://hdl.handle.net/10948/683 , Blind children -- Education -- South Africa -- Port Elizabeth , Children with visual disabilities -- Education -- South Africa -- Port Elizabeth , Special education -- South Africa -- Port Elizabeth
- Description: This research focuses on the perceptions of future fulfilment of visually impaired adolescent learners at the Khanyisa Special School. The qualitative research was undertaken at the selected special school, which is situated in Nelson Mandela Bay in the western region of the Eastern Cape Province of South Africa, with ten learners, ten parents and five teachers as participants. The concluding chapter suggests ways and recommendations to assist the visually impaired adolescent learners at the Khanyisa Special School financially and academically.
- Full Text:
- Date Issued: 2008
Perspectives of teachers on the problem of child sexual abuse in a squatter camp
- Authors: Bashman, Lindelwa Edna
- Date: 2008
- Subjects: Child sexual abuse -- South Africa -- Port Elizabeth , Sexually abused children -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9537 , http://hdl.handle.net/10948/684 , Child sexual abuse -- South Africa -- Port Elizabeth , Sexually abused children -- South Africa -- Port Elizabeth
- Description: Child sexual abuse is a worldwide phenomenon that takes a major toll in squatter camps in South Africa. The conditions under which the squatters live promote and aggravate the abuse. Sadly, the victims hit hardest by the abuse are the children. The negative effects caused by the abuse lead to problems in the educational tasks of these children. This study proposes that teachers can play a significant role in assisting them to overcome their problem. The aim of this study was to: • investigate the perceptions of teachers of the problem of the sexual abuse of children coming from squatter camps; • empower teachers with strategies that will help to alleviate the problem; and • formulate some recommendations on dealing with the situation in the classroom. The literature was reviewed with the aim of substantiating a compact theoretical basis for the study. Various aspects were discussed, such as • the different definitions of child sexual abuse; • short- and long-term effects of the abuse; and • contributory factors of child sexual abuse. This study followed a qualitative design, which is interpretive, naturalistic, descriptive, holistic and exploratory in nature. The participants, chosen purposefully for this study, were ten teachers, teaching children coming from a squatter camp in the Motherwell Township of Nelson Mandela Bay. Themes that emerged from the transcripts of the interviews were: • Sexual abuse has a negative effect on children and causes them to develop problems. • Teachers can play a significant role in assisting learners who are sexually abused. • There are various reasons why sexual abuse is prevalent in squatter camps. The recommendations made are based on the findings of this study and propose to empower teachers so that they will be able to make a difference in the lives of their abused learners.
- Full Text:
- Date Issued: 2008
- Authors: Bashman, Lindelwa Edna
- Date: 2008
- Subjects: Child sexual abuse -- South Africa -- Port Elizabeth , Sexually abused children -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9537 , http://hdl.handle.net/10948/684 , Child sexual abuse -- South Africa -- Port Elizabeth , Sexually abused children -- South Africa -- Port Elizabeth
- Description: Child sexual abuse is a worldwide phenomenon that takes a major toll in squatter camps in South Africa. The conditions under which the squatters live promote and aggravate the abuse. Sadly, the victims hit hardest by the abuse are the children. The negative effects caused by the abuse lead to problems in the educational tasks of these children. This study proposes that teachers can play a significant role in assisting them to overcome their problem. The aim of this study was to: • investigate the perceptions of teachers of the problem of the sexual abuse of children coming from squatter camps; • empower teachers with strategies that will help to alleviate the problem; and • formulate some recommendations on dealing with the situation in the classroom. The literature was reviewed with the aim of substantiating a compact theoretical basis for the study. Various aspects were discussed, such as • the different definitions of child sexual abuse; • short- and long-term effects of the abuse; and • contributory factors of child sexual abuse. This study followed a qualitative design, which is interpretive, naturalistic, descriptive, holistic and exploratory in nature. The participants, chosen purposefully for this study, were ten teachers, teaching children coming from a squatter camp in the Motherwell Township of Nelson Mandela Bay. Themes that emerged from the transcripts of the interviews were: • Sexual abuse has a negative effect on children and causes them to develop problems. • Teachers can play a significant role in assisting learners who are sexually abused. • There are various reasons why sexual abuse is prevalent in squatter camps. The recommendations made are based on the findings of this study and propose to empower teachers so that they will be able to make a difference in the lives of their abused learners.
- Full Text:
- Date Issued: 2008
Physical activity in the lives of two generations of black professional women in the Nelson Mandela Metropolitan Municipality
- Authors: Walter, Cheryl Michelle
- Date: 2008
- Subjects: Physical education for women , Physical fitness for women , Women -- Health and hygiene
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10089 , http://hdl.handle.net/10948/664 , Physical education for women , Physical fitness for women , Women -- Health and hygiene
- Description: The association between physical inactivity, adverse health and hypokinetic diseases has been widely researched. There is an increased risk of being overweight, and of developing certain chronic diseases and suffering premature death associated with physical inactivity (Young, Miller, Wilder, Yanek & Becker, 1998). Recent surveys and studies have revealed that the majority of the South African population has moved extensively along the epidemiological transition towards a disease profile related to Western lifestyle, where deaths due to chronic diseases of lifestyle is a great cause for concern (Steyn, 2006). Black women, in particular, have been identified as a high risk group with the highest levels of inactivity and the highest levels of overweight and obesity in the country (SADHS, 1998; WHO, 2005). Although there is a growing body of knowledge and research on physical activity in general, there is still a lack of data on the determinants and barriers to participation in physical activity (Lambert & Kolbe-Alexander, 2006). Cultural patterns and economic, political and ideological orders affect the participation of women in sport (Hargreaves, 1994:5). Black women in South Africa have been disadvantaged by the past government’s policy of apartheid, and have also been marginalized and oppressed in their own patriarchal societies. The first democratically elected government in 1994, however, committed itself to gender equality and women’s emancipation, with constitutional guarantees on equality and an affirmative action policy to address gender inequalities. In order to evaluate the extent of the beneficial impact of these political changes in women’s lives, this study proposed to investigate physical activity patterns in the lives of two generations of black professional women (teachers, nurses, social workers and public managers) from the Nelson Mandela Metropolitan Municipality. The objectives that guided the research were: • To describe and compare the physical activity patterns and health status of two generations of black women through questionnaires, physical activity records and mechanical devices. • To explore and describe the psychosocial context and socio-cultural influences on physical activity in the lives of the participants. xi • To explore and describe the participants’ perceptions and attitudes, motivations and constraints relating to physical activity. • To use the research findings to compile guidelines to promote physical activity participation among black women. A mixed method approach using both quantitative and qualitative methods was selected to achieve an holistic understanding of physical activity in the lives of black South African women. The older generation (OG) of professional women was comprised of community teachers, nurses, social workers and public managers (n=111, aged 35 to 45 years, mean age = 39.87 years). These women, through their occupations, were in constant contact with the community and could be regarded as role models who influence community lifestyle, attitudes and behaviour. The younger generation (YG) (n=69, aged 18 to 21 years, mean age = 20.12 years) was comprised of teaching, nursing, social work and public management students in the Nelson Mandela Metropolitan Municipality. The objective of the quantitative section of the study was to provide baseline information on the physical activity patterns and health status of these two generations of black professional women. Physical activity and health questionnaires were administered and the ActiGraph GT1 accelerometer was used to provide an objective measure of energy expenditure. The objective of the qualitative data collection was to explore and describe the psychosocial context and socio-cultural influences on physical activity in the lives of the participants, and to investigate their attitudes to and perceptions of physical activity, and their motivations and constraints related to it. In-depth qualitative interviews were held with the participants who wore the ActiGraph, and a group of 47 were interviewed (sample size determined by data saturation from the interviews). An explorative-descriptive research design was used in the study. The sampling method was purposive and criterion-based. The younger generation of students were mostly selected from the various campuses of the Nelson Mandela Metropolitan University, while additional student nurses were recruited from the Lilitha Nursing College in the Nelson Mandela Metropolitan Municipality. The older generation of professionals were recruited from schools and clinics in the areas of New Brighton, Kwa-Zakhele, Zwide, Motherwell and Kwa-Nobuhle (all historically black areas), the Eastern Cape Department of Social Development, non-government organizations and the Nelson Mandela Metropolitan Municipality. xii The quantitative data were analysed by means of descriptive and inferential statistics. The qualitative data was analysed according to the steps described in Creswell (2003). The results of the quantitative data indicated that prevalence of overweight and obesity among both the YG and OG was high. The mean BMI for the YG and OG were 24.71 kg/m2 and 31.27 kg/m2, respectively, with 41% of the YG and 86% of the OG falling into the overweight/obesity category. BMI was significantly greater (p<.05) for the OG than for the YG. In addition, both the OG and YG had satisfactory scores for the health-related behaviour measures (the Belloc and Breslow Lifestyle Index and the HPLP). All the physical activity measurements (the FIT Index of Kasari, the GPAQ and the ActiGraph data) confirmed that both the YG and OG were not sufficiently physically active. They did not meet the Centre of Disease Control (CDC) and American College of Sports Medicine (ACSM) recommendation of engaging in at least 30 minutes of moderate-intensity physical activity on most, or preferably all, days of the week. The YG were significantly more active than the OG in all the physical activity measuring instruments. They were still, however, not reaching the health enhancing physical activity (HEPA) level (≥7 days of any combination of moderate and vigorous activity, ≥ 3000 METmins/week). Pearson Product Moment correlations were calculated to determine the relationship among the various measurements of physical activity o the one hand and the relationship between the measurements of physical activity and the health-related behaviour measurements on the other hand. The correlational analyses highlighted a good cross-validation of the various measures of physical activity. There was a significant correlation between the measures of leisure time physical activity, that is the FIT Index, and the leisure domain of the GPAQ. There was also a significant relationship in the area of walking or steps taken, that is the ActiGraph steps and the GPAQ transport domain. There was also a significant relationship between the overall measures of physical activity, that is the GPAQ total score, and the ActiGraph calories. The correlations between the various physical activity and health related behaviour measures revealed that only the leisure related physical activity measurements, that is, the FIT index and the GPAQ leisure domain, had a significant correlation with the two health related behaviour measures, namely the Belloc and Breslow Lifestyle Index and the HPLP, respectively. xiii The results from the qualitative data revealed that both the OG and YG had positive attitudes towards physical activity participation (displayed by their awareness of the many benefits, their expressed intention to start exercising, the encouragement given to their children in relation to physical activity participation), even though the majority of them were not active on a regular basis. Participants recognized the educational, recreational and developmental importance of being physically active, a shift in attitude from their own upbringing and lifestyles. Regardless of how firmly people may believe that physical activity is beneficial to their health, there are many barriers, whether real or perceived, that represent significant potential obstructions to the adoption, maintenance, or resumption of participation in physical activity (Booth et al., 1997). Three sub-themes were identified in relation to the barriers to physical activity participation, namely personal factors, environmental factors and socio-cultural factors. The personal factors included time constraints, stress and tiredness, lack of motivation, negative school experiences, negative associations with exercise and financial constraints. The environmental factors included residential areas, availability of recreation and sports facilities, and safety. The socio-cultural factors were lack of social support, exercise “not being a part of African culture”, traditional roles of males and females, dress code, exercise associated with the young, exercise associated with undesirable weight loss and negative comments by the community. On the basis of research findings, guidelines were drawn up for the promotion of physical activity participation among black women.
- Full Text:
- Date Issued: 2008
- Authors: Walter, Cheryl Michelle
- Date: 2008
- Subjects: Physical education for women , Physical fitness for women , Women -- Health and hygiene
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10089 , http://hdl.handle.net/10948/664 , Physical education for women , Physical fitness for women , Women -- Health and hygiene
- Description: The association between physical inactivity, adverse health and hypokinetic diseases has been widely researched. There is an increased risk of being overweight, and of developing certain chronic diseases and suffering premature death associated with physical inactivity (Young, Miller, Wilder, Yanek & Becker, 1998). Recent surveys and studies have revealed that the majority of the South African population has moved extensively along the epidemiological transition towards a disease profile related to Western lifestyle, where deaths due to chronic diseases of lifestyle is a great cause for concern (Steyn, 2006). Black women, in particular, have been identified as a high risk group with the highest levels of inactivity and the highest levels of overweight and obesity in the country (SADHS, 1998; WHO, 2005). Although there is a growing body of knowledge and research on physical activity in general, there is still a lack of data on the determinants and barriers to participation in physical activity (Lambert & Kolbe-Alexander, 2006). Cultural patterns and economic, political and ideological orders affect the participation of women in sport (Hargreaves, 1994:5). Black women in South Africa have been disadvantaged by the past government’s policy of apartheid, and have also been marginalized and oppressed in their own patriarchal societies. The first democratically elected government in 1994, however, committed itself to gender equality and women’s emancipation, with constitutional guarantees on equality and an affirmative action policy to address gender inequalities. In order to evaluate the extent of the beneficial impact of these political changes in women’s lives, this study proposed to investigate physical activity patterns in the lives of two generations of black professional women (teachers, nurses, social workers and public managers) from the Nelson Mandela Metropolitan Municipality. The objectives that guided the research were: • To describe and compare the physical activity patterns and health status of two generations of black women through questionnaires, physical activity records and mechanical devices. • To explore and describe the psychosocial context and socio-cultural influences on physical activity in the lives of the participants. xi • To explore and describe the participants’ perceptions and attitudes, motivations and constraints relating to physical activity. • To use the research findings to compile guidelines to promote physical activity participation among black women. A mixed method approach using both quantitative and qualitative methods was selected to achieve an holistic understanding of physical activity in the lives of black South African women. The older generation (OG) of professional women was comprised of community teachers, nurses, social workers and public managers (n=111, aged 35 to 45 years, mean age = 39.87 years). These women, through their occupations, were in constant contact with the community and could be regarded as role models who influence community lifestyle, attitudes and behaviour. The younger generation (YG) (n=69, aged 18 to 21 years, mean age = 20.12 years) was comprised of teaching, nursing, social work and public management students in the Nelson Mandela Metropolitan Municipality. The objective of the quantitative section of the study was to provide baseline information on the physical activity patterns and health status of these two generations of black professional women. Physical activity and health questionnaires were administered and the ActiGraph GT1 accelerometer was used to provide an objective measure of energy expenditure. The objective of the qualitative data collection was to explore and describe the psychosocial context and socio-cultural influences on physical activity in the lives of the participants, and to investigate their attitudes to and perceptions of physical activity, and their motivations and constraints related to it. In-depth qualitative interviews were held with the participants who wore the ActiGraph, and a group of 47 were interviewed (sample size determined by data saturation from the interviews). An explorative-descriptive research design was used in the study. The sampling method was purposive and criterion-based. The younger generation of students were mostly selected from the various campuses of the Nelson Mandela Metropolitan University, while additional student nurses were recruited from the Lilitha Nursing College in the Nelson Mandela Metropolitan Municipality. The older generation of professionals were recruited from schools and clinics in the areas of New Brighton, Kwa-Zakhele, Zwide, Motherwell and Kwa-Nobuhle (all historically black areas), the Eastern Cape Department of Social Development, non-government organizations and the Nelson Mandela Metropolitan Municipality. xii The quantitative data were analysed by means of descriptive and inferential statistics. The qualitative data was analysed according to the steps described in Creswell (2003). The results of the quantitative data indicated that prevalence of overweight and obesity among both the YG and OG was high. The mean BMI for the YG and OG were 24.71 kg/m2 and 31.27 kg/m2, respectively, with 41% of the YG and 86% of the OG falling into the overweight/obesity category. BMI was significantly greater (p<.05) for the OG than for the YG. In addition, both the OG and YG had satisfactory scores for the health-related behaviour measures (the Belloc and Breslow Lifestyle Index and the HPLP). All the physical activity measurements (the FIT Index of Kasari, the GPAQ and the ActiGraph data) confirmed that both the YG and OG were not sufficiently physically active. They did not meet the Centre of Disease Control (CDC) and American College of Sports Medicine (ACSM) recommendation of engaging in at least 30 minutes of moderate-intensity physical activity on most, or preferably all, days of the week. The YG were significantly more active than the OG in all the physical activity measuring instruments. They were still, however, not reaching the health enhancing physical activity (HEPA) level (≥7 days of any combination of moderate and vigorous activity, ≥ 3000 METmins/week). Pearson Product Moment correlations were calculated to determine the relationship among the various measurements of physical activity o the one hand and the relationship between the measurements of physical activity and the health-related behaviour measurements on the other hand. The correlational analyses highlighted a good cross-validation of the various measures of physical activity. There was a significant correlation between the measures of leisure time physical activity, that is the FIT Index, and the leisure domain of the GPAQ. There was also a significant relationship in the area of walking or steps taken, that is the ActiGraph steps and the GPAQ transport domain. There was also a significant relationship between the overall measures of physical activity, that is the GPAQ total score, and the ActiGraph calories. The correlations between the various physical activity and health related behaviour measures revealed that only the leisure related physical activity measurements, that is, the FIT index and the GPAQ leisure domain, had a significant correlation with the two health related behaviour measures, namely the Belloc and Breslow Lifestyle Index and the HPLP, respectively. xiii The results from the qualitative data revealed that both the OG and YG had positive attitudes towards physical activity participation (displayed by their awareness of the many benefits, their expressed intention to start exercising, the encouragement given to their children in relation to physical activity participation), even though the majority of them were not active on a regular basis. Participants recognized the educational, recreational and developmental importance of being physically active, a shift in attitude from their own upbringing and lifestyles. Regardless of how firmly people may believe that physical activity is beneficial to their health, there are many barriers, whether real or perceived, that represent significant potential obstructions to the adoption, maintenance, or resumption of participation in physical activity (Booth et al., 1997). Three sub-themes were identified in relation to the barriers to physical activity participation, namely personal factors, environmental factors and socio-cultural factors. The personal factors included time constraints, stress and tiredness, lack of motivation, negative school experiences, negative associations with exercise and financial constraints. The environmental factors included residential areas, availability of recreation and sports facilities, and safety. The socio-cultural factors were lack of social support, exercise “not being a part of African culture”, traditional roles of males and females, dress code, exercise associated with the young, exercise associated with undesirable weight loss and negative comments by the community. On the basis of research findings, guidelines were drawn up for the promotion of physical activity participation among black women.
- Full Text:
- Date Issued: 2008
Phytoplankton chlorophyll a concentration and community structure in two temporarily open/closed estuaries in the Eastern Cape, South Africa
- Authors: Gama, Phumelele Thuthuka
- Date: 2008
- Subjects: Estuarine ecology -- South Africa , Chlorophyll -- South Africa , Estuaries -- South Africa , Phytoplankton populations -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10621 , http://hdl.handle.net/10948/707 , Estuarine ecology -- South Africa , Chlorophyll -- South Africa , Estuaries -- South Africa , Phytoplankton populations -- South Africa
- Description: River flow is important in controlling phytoplankton distribution in estuaries. Data on the effect of river inflow on phytoplankton distribution patterns in temporarily open/closed estuaries is lacking. This study investigated the influence of river inflow on size-fractionated phytoplankton biomass (Chl a), community composition and environmental parameters measured monthly over three years in two temporarily open/closed estuaries in the Eastern Cape, South Africa. A once-off primary production study over an annual cycle was completed in the Van Stadens and Maitland estuaries. The study monitored physical, chemical and biological characteristics in both estuaries to examine the effects of changes in environmental factors and river inflow. Daily sampling of physico-chemical and biological variables from river to sea was carried out in the Van Stadens to investigate short-time scale effects of changes in environmental factors and river inflow on the phytoplankton biomass. Five and three stations in the main channel of the Van Stadens and Maitland estuaries respectively were sampled at 0.5 m below the water surface and 0.5 m above the sediment surface for biological and chemical variables and at the surface, 0.25 m and every 0.5 m thereafter for physical parameters. Five stations adjacent to the main channel along the estuary were monitored for groundwater macronutrient concentrations and five additional sites located within the upper catchment of the Van Stadens River were sampled on a quarterly basis over two years. Both estuaries were characterised by distinct hydrological conditions, an overwash, an open, a closed and a semi-closed mouth phase. Flooding in the Maitland and Van Stadens estuaries in 2001 and 2002 caused sediment scour, altered channel morphology and brought about breaching of the mouth. Flood driven mouth-breaching events occurred three and four times in each of the estuaries during the study. The mouth stayed open 20 – 25 percent and was closed 60 – 65 percent of the time. In the Van Stadens the closed overwash mouth condition occurred approximately 10 – 20 percent of the time while in the Maitland it occurred less with the semi-closed mouth condition occurring 10 – 20 percent of the time. Incidents related to mouth opening not associated with strong river floods occurred approximately 10 – 15 percent of the time, although in the Maitland a semi-closed mouth state persisted more frequently than in the Van Stadens Estuary. During flooding events salinity dropped to low levels (< 5 psu) but soon recovered to brackish conditions when river flow was reduced and marine water penetrated deep upstream. Reduction in river flow combined with marine sediment deposition resulted in the closure of the mouth. During closed mouth conditions strong onshore storm surges and spring high tides introduced marine water through overwash that kept salinity high. In both estuaries salinity showed a negative correlation with rainfall (R2 = 0.12), indicative of the strong influence of marine overwash that kept salinity high thus masking the influence of freshwater. High rainfall in the Van Stadens Estuary caused high levels of turbidity that reduced light penetration at depth. Light attenuation was positively correlated with the high rainfall (R 2 = 0.26) suggesting that increased turbidity was linked to rainfall induced discharge. In contrast, in the Maitland Estuary light attenuation did not show any correlation with increased rainfall possibly because of the reduced water depth and increased euphotic zone following the floods in 2002. High river inflow introduced macronutrients in both estuaries such that dissolved inorganic phosphates (DIP) and dissolved inorganic nitrogen (DIN) concentrations in the Van Stadens Estuary were strongly correlated with rainfall (R2 = 0.78 and 0.57 respectively). In the Maitland Estuary DIP and DIN concentrations remained significantly higher (p < 0.05) compared to that in the Van Stadens suggesting that the Maitland catchment contributed greater nutrient input into the estuary and may be associated with farming activities. Phytoplankton chlorophyll a (Chl a) ranged from 0.8 – 13.9 μg L-1 in the Van Stadens and in the Maitland Estuary from 5.3 – 138 μg L-1 during the 3-year study. During the open mouth condition Chl a biomass and primary production ranged from 5.4 – 52.9 μg Chl a L-1 and 1.2 – 11.7 mg C m-2 d-1 in the Maitland and in the Van Stadens from 1.6 – 9.8 μg Chl a L-1 and 1.2 - 14 mg C m-2 d-1 respectively. Maximum annual primary production in the Maitland and Van Stadens estuaries was 8.8 and 5.1 g C m-2 y-1 respectively. When the mouth was open in the Van Stadens Estuary the microphytoplankton (> 20 μm) accounted for > 65 percent of the Chl a, whereas during closed mouth conditions they accounted for about 55 percent of the Chl a biomass. Chlorophytes became the dominant taxon in the dry summer months but were replaced by cryptophytes and dinoflagellates during the wet season. When nutrient concentrations were low during low flow conditions in the Van Stadens Estuary mixotrophic microphytoplankton became an important fraction of the water column together with phototrophic dinoflagellates and cryptophytes. In the Maitland large sized chlorophytes were the dominant taxa in late spring and summer seasons and made up more than 80 percent of the cell numbers. In the Maitland before the floods in 2002 cyanophytes were the dominant group in late spring contributing more than 75 percent in cell abundance. Data from the short-term study in the Van Stadens Estuary showed similarities and differences in the Chl a response to increased river inflow. High river inflow initially reduced Chl a biomass followed by a recovery period of a couple of days compared to a 8 – 10 week recovery period in studies monitored over seasonal and annual temporal scales. The responses may be dissimilar but help to illustrate that there are similar response patterns to environmental forcing necessary to support phytoplankton biomass at different temporal scales. This study has demonstrated that flooding events caused by strong river flow cause breaching of the mouth, a reduction in salinity and marked nutrient input. Although the causes of flooding can be similar in both estuaries the resultant effects are varied and can alter the ability of the estuary to retain water. This study was able to demonstrate that the supply of macronutrients from the catchment was strongly correlated with rainfall (R2 = 0.67) and that phytoplankton growth mainly depended on an allochthonous source of macronutrients although internal supplies could be critical at times in controlling microalgal biomass.
- Full Text:
- Date Issued: 2008
- Authors: Gama, Phumelele Thuthuka
- Date: 2008
- Subjects: Estuarine ecology -- South Africa , Chlorophyll -- South Africa , Estuaries -- South Africa , Phytoplankton populations -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10621 , http://hdl.handle.net/10948/707 , Estuarine ecology -- South Africa , Chlorophyll -- South Africa , Estuaries -- South Africa , Phytoplankton populations -- South Africa
- Description: River flow is important in controlling phytoplankton distribution in estuaries. Data on the effect of river inflow on phytoplankton distribution patterns in temporarily open/closed estuaries is lacking. This study investigated the influence of river inflow on size-fractionated phytoplankton biomass (Chl a), community composition and environmental parameters measured monthly over three years in two temporarily open/closed estuaries in the Eastern Cape, South Africa. A once-off primary production study over an annual cycle was completed in the Van Stadens and Maitland estuaries. The study monitored physical, chemical and biological characteristics in both estuaries to examine the effects of changes in environmental factors and river inflow. Daily sampling of physico-chemical and biological variables from river to sea was carried out in the Van Stadens to investigate short-time scale effects of changes in environmental factors and river inflow on the phytoplankton biomass. Five and three stations in the main channel of the Van Stadens and Maitland estuaries respectively were sampled at 0.5 m below the water surface and 0.5 m above the sediment surface for biological and chemical variables and at the surface, 0.25 m and every 0.5 m thereafter for physical parameters. Five stations adjacent to the main channel along the estuary were monitored for groundwater macronutrient concentrations and five additional sites located within the upper catchment of the Van Stadens River were sampled on a quarterly basis over two years. Both estuaries were characterised by distinct hydrological conditions, an overwash, an open, a closed and a semi-closed mouth phase. Flooding in the Maitland and Van Stadens estuaries in 2001 and 2002 caused sediment scour, altered channel morphology and brought about breaching of the mouth. Flood driven mouth-breaching events occurred three and four times in each of the estuaries during the study. The mouth stayed open 20 – 25 percent and was closed 60 – 65 percent of the time. In the Van Stadens the closed overwash mouth condition occurred approximately 10 – 20 percent of the time while in the Maitland it occurred less with the semi-closed mouth condition occurring 10 – 20 percent of the time. Incidents related to mouth opening not associated with strong river floods occurred approximately 10 – 15 percent of the time, although in the Maitland a semi-closed mouth state persisted more frequently than in the Van Stadens Estuary. During flooding events salinity dropped to low levels (< 5 psu) but soon recovered to brackish conditions when river flow was reduced and marine water penetrated deep upstream. Reduction in river flow combined with marine sediment deposition resulted in the closure of the mouth. During closed mouth conditions strong onshore storm surges and spring high tides introduced marine water through overwash that kept salinity high. In both estuaries salinity showed a negative correlation with rainfall (R2 = 0.12), indicative of the strong influence of marine overwash that kept salinity high thus masking the influence of freshwater. High rainfall in the Van Stadens Estuary caused high levels of turbidity that reduced light penetration at depth. Light attenuation was positively correlated with the high rainfall (R 2 = 0.26) suggesting that increased turbidity was linked to rainfall induced discharge. In contrast, in the Maitland Estuary light attenuation did not show any correlation with increased rainfall possibly because of the reduced water depth and increased euphotic zone following the floods in 2002. High river inflow introduced macronutrients in both estuaries such that dissolved inorganic phosphates (DIP) and dissolved inorganic nitrogen (DIN) concentrations in the Van Stadens Estuary were strongly correlated with rainfall (R2 = 0.78 and 0.57 respectively). In the Maitland Estuary DIP and DIN concentrations remained significantly higher (p < 0.05) compared to that in the Van Stadens suggesting that the Maitland catchment contributed greater nutrient input into the estuary and may be associated with farming activities. Phytoplankton chlorophyll a (Chl a) ranged from 0.8 – 13.9 μg L-1 in the Van Stadens and in the Maitland Estuary from 5.3 – 138 μg L-1 during the 3-year study. During the open mouth condition Chl a biomass and primary production ranged from 5.4 – 52.9 μg Chl a L-1 and 1.2 – 11.7 mg C m-2 d-1 in the Maitland and in the Van Stadens from 1.6 – 9.8 μg Chl a L-1 and 1.2 - 14 mg C m-2 d-1 respectively. Maximum annual primary production in the Maitland and Van Stadens estuaries was 8.8 and 5.1 g C m-2 y-1 respectively. When the mouth was open in the Van Stadens Estuary the microphytoplankton (> 20 μm) accounted for > 65 percent of the Chl a, whereas during closed mouth conditions they accounted for about 55 percent of the Chl a biomass. Chlorophytes became the dominant taxon in the dry summer months but were replaced by cryptophytes and dinoflagellates during the wet season. When nutrient concentrations were low during low flow conditions in the Van Stadens Estuary mixotrophic microphytoplankton became an important fraction of the water column together with phototrophic dinoflagellates and cryptophytes. In the Maitland large sized chlorophytes were the dominant taxa in late spring and summer seasons and made up more than 80 percent of the cell numbers. In the Maitland before the floods in 2002 cyanophytes were the dominant group in late spring contributing more than 75 percent in cell abundance. Data from the short-term study in the Van Stadens Estuary showed similarities and differences in the Chl a response to increased river inflow. High river inflow initially reduced Chl a biomass followed by a recovery period of a couple of days compared to a 8 – 10 week recovery period in studies monitored over seasonal and annual temporal scales. The responses may be dissimilar but help to illustrate that there are similar response patterns to environmental forcing necessary to support phytoplankton biomass at different temporal scales. This study has demonstrated that flooding events caused by strong river flow cause breaching of the mouth, a reduction in salinity and marked nutrient input. Although the causes of flooding can be similar in both estuaries the resultant effects are varied and can alter the ability of the estuary to retain water. This study was able to demonstrate that the supply of macronutrients from the catchment was strongly correlated with rainfall (R2 = 0.67) and that phytoplankton growth mainly depended on an allochthonous source of macronutrients although internal supplies could be critical at times in controlling microalgal biomass.
- Full Text:
- Date Issued: 2008
Pilates for postural stability in computer users
- Authors: Strydom, Lana
- Date: 2008
- Subjects: Pilates method , Human beings -- Attitude and movement
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10094 , http://hdl.handle.net/10948/867 , Pilates method , Human beings -- Attitude and movement
- Description: The impact of computer use is evident in every day life (Harrington, Carter, Birrell and Gompertz, 2000:264). Lind (2002:18) explains that global trends continue to show that the most severe work-related health problems that exist amongst computer users are musculoskeletal disorders. As technology has lead to increases in automation, so it has lead to increases in work-related illnesses. Although studies have explored the effects of ergonomics (Thibodeau, 1995:322) in static working positions there has been little evidence supporting a solution in overcoming poor occupational postures. Many health practitioners argue that occupationally caused, or aggravated, musculoskeletal disorders are steadily increasing. Thus, even though computers have improved productivity and made work easier for the population in general, they have adverse effects as well. Designing the proper tools or a setup of the work place is of prime importance for the elimination of chronic diseases attributed to sedentary lifestyles. Regular physical activity had long been regarded as an important component of a healthy lifestyle. This notion has recently been reinforced by scientific evidence linking regular physical activity with a wide array of physical and mental health benefits, synonymous with an improvement in wellness (Pratt, Macera, and Wang, 2000:63). According to Pratt et al. (2000:63) higher direct medical costs associates with physical inactivity. Further cross-sectional epidemiologic studies and controlled experimental investigations conducted by Okura, Nakata and Tanaka (2003:1131) had demonstrated that physically active adults, in contrast to their sedentary counterparts, tend to develop and maintain higher levels of physical fitness. These studies had not only demonstrated the positive results of physical activity, such as an improvement in blood lipid profile, body composition, glucose tolerance and insulin sensitivity, but had also shown that participation in such activity decreased the risk of developing several chronic hypokinetic diseases, including coronary heart disease (CHD), hypertension, non-insulin dependant diabetes mellitus (type II), osteoporosis, colon cancer, anxiety and depression. In addition, low levels of habitual physical activity and the subsequent low levels of physical fitness were associated with a marked increase in all-cause mortality rates. Okura et al. (2003:1131) confirm that effects of exercise intensity on physical fitness and risk factors for coronary Herat disease.
- Full Text:
- Date Issued: 2008
- Authors: Strydom, Lana
- Date: 2008
- Subjects: Pilates method , Human beings -- Attitude and movement
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10094 , http://hdl.handle.net/10948/867 , Pilates method , Human beings -- Attitude and movement
- Description: The impact of computer use is evident in every day life (Harrington, Carter, Birrell and Gompertz, 2000:264). Lind (2002:18) explains that global trends continue to show that the most severe work-related health problems that exist amongst computer users are musculoskeletal disorders. As technology has lead to increases in automation, so it has lead to increases in work-related illnesses. Although studies have explored the effects of ergonomics (Thibodeau, 1995:322) in static working positions there has been little evidence supporting a solution in overcoming poor occupational postures. Many health practitioners argue that occupationally caused, or aggravated, musculoskeletal disorders are steadily increasing. Thus, even though computers have improved productivity and made work easier for the population in general, they have adverse effects as well. Designing the proper tools or a setup of the work place is of prime importance for the elimination of chronic diseases attributed to sedentary lifestyles. Regular physical activity had long been regarded as an important component of a healthy lifestyle. This notion has recently been reinforced by scientific evidence linking regular physical activity with a wide array of physical and mental health benefits, synonymous with an improvement in wellness (Pratt, Macera, and Wang, 2000:63). According to Pratt et al. (2000:63) higher direct medical costs associates with physical inactivity. Further cross-sectional epidemiologic studies and controlled experimental investigations conducted by Okura, Nakata and Tanaka (2003:1131) had demonstrated that physically active adults, in contrast to their sedentary counterparts, tend to develop and maintain higher levels of physical fitness. These studies had not only demonstrated the positive results of physical activity, such as an improvement in blood lipid profile, body composition, glucose tolerance and insulin sensitivity, but had also shown that participation in such activity decreased the risk of developing several chronic hypokinetic diseases, including coronary heart disease (CHD), hypertension, non-insulin dependant diabetes mellitus (type II), osteoporosis, colon cancer, anxiety and depression. In addition, low levels of habitual physical activity and the subsequent low levels of physical fitness were associated with a marked increase in all-cause mortality rates. Okura et al. (2003:1131) confirm that effects of exercise intensity on physical fitness and risk factors for coronary Herat disease.
- Full Text:
- Date Issued: 2008
Pneumocystis jiroveci and respiratorey bacterial pathogens in cases of pneumonia at hospitals in Port Elizabeth
- Authors: Du Plessis, Sarah Jane
- Date: 2008
- Subjects: Pneumocystis carinii pneumonia , Tuberculosis -- pathogenesis , Opportunistic infections
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10328 , http://hdl.handle.net/10948/946 , Pneumocystis carinii pneumonia , Tuberculosis -- pathogenesis , Opportunistic infections
- Description: Pneumocystis jiroveci, Mycoplasma pneumoniae and Mycobacterium tuberculosis are respiratory pathogens associated with pneumonia, with increasing prevalence of Pneumocystis pneumonia (PcP) and tuberculosis (TB) in AIDS patients. Increased resistance of M. tuberculosis has emphasized the need for rapid susceptibility testing, such as flow cytometry. Sputum specimens (102) were assessed by PCR employing primers directed at the following genes: P. jiroveci: mitochondrial large subunit ribosomal RNA (mtLSUrRNA), dihydropteroate synthase (DHPS) and dihydrofolate reductase (DHFR), and for M. pneumoniae: 16S rRNA and P1 adhesin. Positive P. jiroveci samples were genotyped by PCR-SSCP (single-strand conformation polymorphism) targeting the: internal transcribed spacer region (ITS), intron of the nuclear 26S rRNA gene (26S), variable region of the mitochondrial 26S rRNA gene (mt26S) and β-tubulin gene (β-tub). Multi-drug resistant (MDR-TB) cultures grown in the presence and absence of four antibiotics (rifampicin, isoniazid, ethambutol and ofloxacin) were heat killed, stained with SYTO16 and Propidium Iodide and analysed using flow cytometry. Rifampicin resistance gene mutations were screened by PCR and DNA sequencing. Details of patient’s gender, age, HIV and M. tuberculosis status were provided by the hospitals. Women were seen to be at high risk for community-acquired P. jiroveci colonisation. Overall, prevalence of P. jiroveci was 55.1 percent (54/102 patients). P. jiroveci was mainly associated with HIV (25/102 P. jiroveci positive patients for which clinical data was available) and co-colonisation with M. tuberculosis was observed in 11 cases. Sequence analysis of DHPS and DHFR products found no resistance associated mutations. M. pneumoniae was detected in one patient. Four simple SSCP patterns were identified and there were no co-infections with other P. jiroveci strains. Nine M. tuberculosis samples [8 MDR-TB isolates (NHLS) and M. tuberculosis ATCC® 27294TM] were tested. There was a 53 percent (19 out of 36 tests) agreement of flow cytometry with the BACTEC MGIT 960. Mutations (at two specific codons, namely 516 and 531) in the rifampicin resistance-determining region (RRDR) of the rpoB gene were observed in eight M. tuberculosis isolates. Evaluation of methods for genotyping and drug susceptibility testing of PcP and TB are imperative for epidemiology and drug resistance studies, and impact on treatment protocols.
- Full Text:
- Date Issued: 2008
- Authors: Du Plessis, Sarah Jane
- Date: 2008
- Subjects: Pneumocystis carinii pneumonia , Tuberculosis -- pathogenesis , Opportunistic infections
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10328 , http://hdl.handle.net/10948/946 , Pneumocystis carinii pneumonia , Tuberculosis -- pathogenesis , Opportunistic infections
- Description: Pneumocystis jiroveci, Mycoplasma pneumoniae and Mycobacterium tuberculosis are respiratory pathogens associated with pneumonia, with increasing prevalence of Pneumocystis pneumonia (PcP) and tuberculosis (TB) in AIDS patients. Increased resistance of M. tuberculosis has emphasized the need for rapid susceptibility testing, such as flow cytometry. Sputum specimens (102) were assessed by PCR employing primers directed at the following genes: P. jiroveci: mitochondrial large subunit ribosomal RNA (mtLSUrRNA), dihydropteroate synthase (DHPS) and dihydrofolate reductase (DHFR), and for M. pneumoniae: 16S rRNA and P1 adhesin. Positive P. jiroveci samples were genotyped by PCR-SSCP (single-strand conformation polymorphism) targeting the: internal transcribed spacer region (ITS), intron of the nuclear 26S rRNA gene (26S), variable region of the mitochondrial 26S rRNA gene (mt26S) and β-tubulin gene (β-tub). Multi-drug resistant (MDR-TB) cultures grown in the presence and absence of four antibiotics (rifampicin, isoniazid, ethambutol and ofloxacin) were heat killed, stained with SYTO16 and Propidium Iodide and analysed using flow cytometry. Rifampicin resistance gene mutations were screened by PCR and DNA sequencing. Details of patient’s gender, age, HIV and M. tuberculosis status were provided by the hospitals. Women were seen to be at high risk for community-acquired P. jiroveci colonisation. Overall, prevalence of P. jiroveci was 55.1 percent (54/102 patients). P. jiroveci was mainly associated with HIV (25/102 P. jiroveci positive patients for which clinical data was available) and co-colonisation with M. tuberculosis was observed in 11 cases. Sequence analysis of DHPS and DHFR products found no resistance associated mutations. M. pneumoniae was detected in one patient. Four simple SSCP patterns were identified and there were no co-infections with other P. jiroveci strains. Nine M. tuberculosis samples [8 MDR-TB isolates (NHLS) and M. tuberculosis ATCC® 27294TM] were tested. There was a 53 percent (19 out of 36 tests) agreement of flow cytometry with the BACTEC MGIT 960. Mutations (at two specific codons, namely 516 and 531) in the rifampicin resistance-determining region (RRDR) of the rpoB gene were observed in eight M. tuberculosis isolates. Evaluation of methods for genotyping and drug susceptibility testing of PcP and TB are imperative for epidemiology and drug resistance studies, and impact on treatment protocols.
- Full Text:
- Date Issued: 2008
Practical and scalable synthesis of N-Alkyl-N,N'Diacylhydrazines
- Authors: Gouws, Melissa Claire
- Date: 2008
- Subjects: Chemistry, Organic , Acylation , Insecticides
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:10406 , http://hdl.handle.net/10948/696 , Chemistry, Organic , Acylation , Insecticides
- Description: The work presented in this thesis is concerned with the evaluation of potential synthetic routes for the diacylhydrazine group of compounds, and particularly, unsymmetrical diacylhydrazines. Diacylhydrazines form the basis for a relatively new group of insecticides that have molt accelerating properties, and which are considered to offer substantial advantages over other insecticides used for the control of certain insects. The overall objective for this study is to evaluate different potential synthetic routes for a model diacylhydrazine with the view to define potentially scaleable routes. The compound selected for this study was the unsymmetrical diacylhydrazine, N-[N-(tertbutyl) phenylcarbonylamino](4-methylphenyl)-carboxamide since it offers the same range of challenges that would be expected for the synthesis of other similar unsymmetrical diacylhydrazines. Thus, the synthesis of unsymmetrical diacylhydrazines require two reaction steps: The first step is the synthesis of the intermediate mono-acylhydrazine, while the second step is the synthesis of the desired diacylhydrazine from the intermediate mono-acylhydrazine. The most important factor in the two-step reaction sequence is to obtain a high degree of selectivity for the desired mono-acylhydrazine isomer. Acylation of t-butylhydrazine using 4-methylbenzoyl chloride can produce the desired product N-[(tert-butyl)amino](4-methylphenyl)carboxamide in yields above 90 percent, but this reaction produces a variety of by-products, including the “wrong” isomer (N-amino-N- (tert-butyl)(4-methylphenyl)carboximide). Unexpected byproducts for this particular acylation reaction, not previously reported in the literature have also been identified during this investigation. This includes a de-butylated diacylhydrazine, (4-methylphenyl)- N-[(4-methylphenyl)carbonylamino] carboxamide. Although the reaction between tert-butylhydrazine and 4-methylbenzaldehyde is very selective giving near quantitative yields of the desired hydrazone, the subsequent conversion of the hydrazone into the desired mono-acylhydrazine is problematic. The most promising route appears via bromination to form the hydrazidic bromide, followed by hydrolysis of the hydrazidic bromide. Yields for the bromination reaction during this investigation were somewhat higher than that reported previously in literature. Hydrolysis of the hydrazidic bromide, apparently also results in the hydrolysis of the reaction product to give an ester of the free acid (when an ester solvent is used). The synthesis of N-[N-(tert-butyl)phenylcarbonylamino](4-methyl phenyl)carboxamide was only briefly considered to evaluate essentially two approaches, namely: · The conversion of the monoacylhydrazine, N-[(tert-butyl)amino](4- methylphenyl)carboxamide, by acylating with either benzoyl chloride or methylbenzoate (gave 86 percent N-[N-(tert-butyl)phenylcarbonylamino](4-methyl phenyl)carboxamide when benzoyl chloride was used as acylating agent); and · The one-pot conversion of the hydrazone, [(1E)-2-(4-methylphenyl)-1- azavinyl](tert-butyl)]amine, by bromination/hydrolysis and acylation. In this case, benzoyl chloride (2 percent N-[N-(tert-butyl)phenylcarbonylamino](4-methyl phenyl)carboxamide), benzoic acid (80.67 percent N-[N-(tertbutyl) phenylcarbonylamino](4-methylphenyl)carboxamide) were evaluated as potential acylating agents.
- Full Text:
- Date Issued: 2008
- Authors: Gouws, Melissa Claire
- Date: 2008
- Subjects: Chemistry, Organic , Acylation , Insecticides
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:10406 , http://hdl.handle.net/10948/696 , Chemistry, Organic , Acylation , Insecticides
- Description: The work presented in this thesis is concerned with the evaluation of potential synthetic routes for the diacylhydrazine group of compounds, and particularly, unsymmetrical diacylhydrazines. Diacylhydrazines form the basis for a relatively new group of insecticides that have molt accelerating properties, and which are considered to offer substantial advantages over other insecticides used for the control of certain insects. The overall objective for this study is to evaluate different potential synthetic routes for a model diacylhydrazine with the view to define potentially scaleable routes. The compound selected for this study was the unsymmetrical diacylhydrazine, N-[N-(tertbutyl) phenylcarbonylamino](4-methylphenyl)-carboxamide since it offers the same range of challenges that would be expected for the synthesis of other similar unsymmetrical diacylhydrazines. Thus, the synthesis of unsymmetrical diacylhydrazines require two reaction steps: The first step is the synthesis of the intermediate mono-acylhydrazine, while the second step is the synthesis of the desired diacylhydrazine from the intermediate mono-acylhydrazine. The most important factor in the two-step reaction sequence is to obtain a high degree of selectivity for the desired mono-acylhydrazine isomer. Acylation of t-butylhydrazine using 4-methylbenzoyl chloride can produce the desired product N-[(tert-butyl)amino](4-methylphenyl)carboxamide in yields above 90 percent, but this reaction produces a variety of by-products, including the “wrong” isomer (N-amino-N- (tert-butyl)(4-methylphenyl)carboximide). Unexpected byproducts for this particular acylation reaction, not previously reported in the literature have also been identified during this investigation. This includes a de-butylated diacylhydrazine, (4-methylphenyl)- N-[(4-methylphenyl)carbonylamino] carboxamide. Although the reaction between tert-butylhydrazine and 4-methylbenzaldehyde is very selective giving near quantitative yields of the desired hydrazone, the subsequent conversion of the hydrazone into the desired mono-acylhydrazine is problematic. The most promising route appears via bromination to form the hydrazidic bromide, followed by hydrolysis of the hydrazidic bromide. Yields for the bromination reaction during this investigation were somewhat higher than that reported previously in literature. Hydrolysis of the hydrazidic bromide, apparently also results in the hydrolysis of the reaction product to give an ester of the free acid (when an ester solvent is used). The synthesis of N-[N-(tert-butyl)phenylcarbonylamino](4-methyl phenyl)carboxamide was only briefly considered to evaluate essentially two approaches, namely: · The conversion of the monoacylhydrazine, N-[(tert-butyl)amino](4- methylphenyl)carboxamide, by acylating with either benzoyl chloride or methylbenzoate (gave 86 percent N-[N-(tert-butyl)phenylcarbonylamino](4-methyl phenyl)carboxamide when benzoyl chloride was used as acylating agent); and · The one-pot conversion of the hydrazone, [(1E)-2-(4-methylphenyl)-1- azavinyl](tert-butyl)]amine, by bromination/hydrolysis and acylation. In this case, benzoyl chloride (2 percent N-[N-(tert-butyl)phenylcarbonylamino](4-methyl phenyl)carboxamide), benzoic acid (80.67 percent N-[N-(tertbutyl) phenylcarbonylamino](4-methylphenyl)carboxamide) were evaluated as potential acylating agents.
- Full Text:
- Date Issued: 2008
Process for the preparation of cis- AND trans-3,7-Dimethyl 2,6-Octadiene-1-OL from crude sulphated turpentine stream
- Sathikge, Ndavheleseni David
- Authors: Sathikge, Ndavheleseni David
- Date: 2008
- Subjects: Turpentine , Sulfate waste liquor , Wood-pulp industry -- By-products
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10398 , http://hdl.handle.net/10948/734 , Turpentine , Sulfate waste liquor , Wood-pulp industry -- By-products
- Description: As part of CSIR Biosciences’ interest in aroma chemicals, the processing of crude sulphated turpentine (CST) into high value aroma products was investigated. The primary target product, linalool, was obtained from a mixture of α- and β-pinene in four steps. It can be transformed into a wide range of high value added aroma chemicals. Isomerisation of linalool in the presence of a transition metal catalyst furnishes geraniol and nerol. The scientific work described in this report was part of a bigger project aimed at developing innovative processes to manufacture aroma, flavour & fragrance chemicals through beneficiation of industrial waste streams and other raw materials, available locally from the Forestry, Paper & Pulp industries. The evaluation of a process for the preparation of precursor aroma, flavour & fragrance compounds, in particular geraniol and nerol, from locally available raw materials and industrial waste streams, was investigated. Preparation of geraniol and nerol from linalool (ex α-pinene stream) was investigated using acids or organometallic complexes as catalysts for the corresponding isomerisation reaction. The investigation was conducted in an effort to find a less costly process utilising milder conditions than via the conventional cleavage of β-pinene to myrcene under extreme pyrolysis conditions (>650°C). The transformation of linalool to geraniol/nerol using mineral acids was found to be dominated by secondary reactions such as dehydration and cyclisation, resulting in poor product selectivities and yields. On the other hand, organometallic complexes, in particular vanadium-based complexes (e.g. (OV(OBu)3) produced satisfactory results in the preliminary assessment (conversion of 79.8 percent and selectivity of 98.3 percent). A set of statistically designed experiments was carried out on the (VO(BuO)3 + [(Bu)4N+]OH¯) catalyst system where three variables were tested, i.e. substrate concentration, temperature, and catalyst loading. The selected model for conversion was significant with the “Probability > F” being < 0.0001. The most important contributing variable to the model for conversion was temperature i.e. 83.9 percent. Temperature was still the most important variable for the selectivity response at 65.0 percent contribution level. The response surface generated for the selectivity response was flat indicating a robust method within the parameter range selected.
- Full Text:
- Date Issued: 2008
- Authors: Sathikge, Ndavheleseni David
- Date: 2008
- Subjects: Turpentine , Sulfate waste liquor , Wood-pulp industry -- By-products
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10398 , http://hdl.handle.net/10948/734 , Turpentine , Sulfate waste liquor , Wood-pulp industry -- By-products
- Description: As part of CSIR Biosciences’ interest in aroma chemicals, the processing of crude sulphated turpentine (CST) into high value aroma products was investigated. The primary target product, linalool, was obtained from a mixture of α- and β-pinene in four steps. It can be transformed into a wide range of high value added aroma chemicals. Isomerisation of linalool in the presence of a transition metal catalyst furnishes geraniol and nerol. The scientific work described in this report was part of a bigger project aimed at developing innovative processes to manufacture aroma, flavour & fragrance chemicals through beneficiation of industrial waste streams and other raw materials, available locally from the Forestry, Paper & Pulp industries. The evaluation of a process for the preparation of precursor aroma, flavour & fragrance compounds, in particular geraniol and nerol, from locally available raw materials and industrial waste streams, was investigated. Preparation of geraniol and nerol from linalool (ex α-pinene stream) was investigated using acids or organometallic complexes as catalysts for the corresponding isomerisation reaction. The investigation was conducted in an effort to find a less costly process utilising milder conditions than via the conventional cleavage of β-pinene to myrcene under extreme pyrolysis conditions (>650°C). The transformation of linalool to geraniol/nerol using mineral acids was found to be dominated by secondary reactions such as dehydration and cyclisation, resulting in poor product selectivities and yields. On the other hand, organometallic complexes, in particular vanadium-based complexes (e.g. (OV(OBu)3) produced satisfactory results in the preliminary assessment (conversion of 79.8 percent and selectivity of 98.3 percent). A set of statistically designed experiments was carried out on the (VO(BuO)3 + [(Bu)4N+]OH¯) catalyst system where three variables were tested, i.e. substrate concentration, temperature, and catalyst loading. The selected model for conversion was significant with the “Probability > F” being < 0.0001. The most important contributing variable to the model for conversion was temperature i.e. 83.9 percent. Temperature was still the most important variable for the selectivity response at 65.0 percent contribution level. The response surface generated for the selectivity response was flat indicating a robust method within the parameter range selected.
- Full Text:
- Date Issued: 2008
Purification and partial characterization of a Myofibril-Bound Serine Protease and its endogenous inhibitor from skeletal muscle of the ostrich
- Tshidino, Shonisani Cathphonia
- Authors: Tshidino, Shonisani Cathphonia
- Date: 2008
- Subjects: Proteolytic enzymes , Ostrich products industry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10330 , http://hdl.handle.net/10948/703 , Proteolytic enzymes , Ostrich products industry
- Description: The ostrich is becoming an important source of meat for humans in developed and developing countries. This study was conducted to purify and characterize myofibrilbound serine protease (MBSP) and its endogenous inhibitor (MBSPI) from skeletal muscle of the ostrich. It is well documented that MBSP is tightly bound to myofibrils and its endogenous inhibitor has been purified from the same tissue of other studied mammalian species. Literature supports an association of MBSP and its endogenous inhibitor with the degradation of myofribrillar proteins, resulting in the softening of muscle that lead to the conversion of muscle into meat with the control of the inhibitor. MBSP was successfully dissociated from washed myofibrils by 40 percent ethylene glycol at pH 8.5. Following centrifugation, MBSP was partially purified in two chromatographic steps, namely Toyopearl Super Q 650S and p-aminobenzamidine-Agarose. On the other hand, MBSPI was fractionated from the sarcoplasmic fraction using 75 percent ammonium sulfate saturation, followed by centrifugation and partially purified by three chromatographic steps, namely Toyopearl Super Q 650S, Superdex 200 and HiTrap SP HR. Ostrich MBSP was physicochemically and kinetically characterized, while MBSPI was only physicochemically characterized. Ostrich MBSP revealed an Mr of 21 kDa, cleaving synthetic fluorogenic substrates specifically at the carboxyl side of arginine residues. Optimum pH and temperature of ostrich MBSP were 8.0 and 40˚C, respectively. Kinetic parameters (Km and Vmax values) were calculated from Lineweaver-Burk plots. The characteristics of ostrich MBSP were compared to the values obtained for commercial bovine trypsin in this study, as well as that obtained for MBSP from various fish species and mouse. The results suggest that ostrich MBSP is a trypsin-like serine protease, thereby confirming the existence of MBSP in ostrich skeletal muscle. Partially purified ostrich MBSPI (Mr 17 kDa) (one form) shares 100 percent identity to myoglobin from the same species, while 2 other forms of MBSPI (Mr values of 35 and 36 kDa) exhibited high sequence identity to glyceraldehyde 3- phosphate dehydrogenase (GAPDH) (76 percent) from human and rat.
- Full Text:
- Date Issued: 2008
- Authors: Tshidino, Shonisani Cathphonia
- Date: 2008
- Subjects: Proteolytic enzymes , Ostrich products industry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10330 , http://hdl.handle.net/10948/703 , Proteolytic enzymes , Ostrich products industry
- Description: The ostrich is becoming an important source of meat for humans in developed and developing countries. This study was conducted to purify and characterize myofibrilbound serine protease (MBSP) and its endogenous inhibitor (MBSPI) from skeletal muscle of the ostrich. It is well documented that MBSP is tightly bound to myofibrils and its endogenous inhibitor has been purified from the same tissue of other studied mammalian species. Literature supports an association of MBSP and its endogenous inhibitor with the degradation of myofribrillar proteins, resulting in the softening of muscle that lead to the conversion of muscle into meat with the control of the inhibitor. MBSP was successfully dissociated from washed myofibrils by 40 percent ethylene glycol at pH 8.5. Following centrifugation, MBSP was partially purified in two chromatographic steps, namely Toyopearl Super Q 650S and p-aminobenzamidine-Agarose. On the other hand, MBSPI was fractionated from the sarcoplasmic fraction using 75 percent ammonium sulfate saturation, followed by centrifugation and partially purified by three chromatographic steps, namely Toyopearl Super Q 650S, Superdex 200 and HiTrap SP HR. Ostrich MBSP was physicochemically and kinetically characterized, while MBSPI was only physicochemically characterized. Ostrich MBSP revealed an Mr of 21 kDa, cleaving synthetic fluorogenic substrates specifically at the carboxyl side of arginine residues. Optimum pH and temperature of ostrich MBSP were 8.0 and 40˚C, respectively. Kinetic parameters (Km and Vmax values) were calculated from Lineweaver-Burk plots. The characteristics of ostrich MBSP were compared to the values obtained for commercial bovine trypsin in this study, as well as that obtained for MBSP from various fish species and mouse. The results suggest that ostrich MBSP is a trypsin-like serine protease, thereby confirming the existence of MBSP in ostrich skeletal muscle. Partially purified ostrich MBSPI (Mr 17 kDa) (one form) shares 100 percent identity to myoglobin from the same species, while 2 other forms of MBSPI (Mr values of 35 and 36 kDa) exhibited high sequence identity to glyceraldehyde 3- phosphate dehydrogenase (GAPDH) (76 percent) from human and rat.
- Full Text:
- Date Issued: 2008
Resilience in families living with a child diagnosed with attention deficit/hyperactivity disorder
- Authors: Theron, Tania
- Date: 2008
- Subjects: Hyperactive children -- Psychological testing , Attention-deficit hyperactivity disorder -- Diagnosis , Attention-deficit-disordered children
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9927 , http://hdl.handle.net/10948/655 , Hyperactive children -- Psychological testing , Attention-deficit hyperactivity disorder -- Diagnosis , Attention-deficit-disordered children
- Description: Attention Deficit/Hyperactivity Disorder (AD/HD) is not a new phenomenon. Researchers have studied children with restless, inattentive and impulsive types of behaviours for over one hundred years. Although the primary distress of AD/HD falls mainly on the child’s shoulders, all family members experience the disorder’s negative effects. While the challenges that families have to face are many, families seem to have the ability to “bounce back” (i.e., they have resilience). There has been limited research to date focusing on the resiliency of families living with children diagnosed with AD/HD. Research on the construct of resilience, and more specifically, family resilience has surged in recent times. However, South African research on family resilience is limited. This study aimed to explore and describe the factors that facilitate adjustment and adaptation in families after a child has been clinically diagnosed with AD/HD. The Resiliency Model of Family Stress, Adjustment and Adaptation, developed by McCubbin and McCubbin (2001) served as a framework to conceptualize the families’ adjustment and adaptation processes. Non-probability purposive sampling was used in order to gain participants for the study. Twenty-two families participated in this study, providing a total of 44 participants. Participants consisted of the caregivers of a family living with a child diagnosed with AD/HD, between the ages of seven and 12. The study was triangular in nature, with an exploratory, descriptive approach. A biographical questionnaire with an open-ended question was used in conjunction with seven other questionnaires to gather data. Descriptive statistics were used to describe the biographical information. Quantitative data were analyzed by means of correlation and regression analysis, and content analysis was used to analyze the qualitative data obtained from the biographical questionnaire. The results of the quantitative analysis indicated six significant positive correlations with the FACI8. These variables were relative and friend support, social support, problem solving and behavioural strategies, family hardiness, family problem-solving communication and family time and routines. The results of the qualitative analysis revealed that social support, adherence to a treatment regime, information and knowledge about AD/HD, a supportive family unit, the caregiver’s acceptance of the disorder as well as communication were the most important strength factors identified. The findings of the research could assist parents in managing their children diagnosed with AD/HD more effectively and has helped create further insight into what resiliency areas they could improve upon. Furthermore, this study could be used as a stepping stone for future research on resilience in families living with a pervasive psychological disorder and will contribute to the broader context of family resilience research in the South African context.
- Full Text:
- Date Issued: 2008
- Authors: Theron, Tania
- Date: 2008
- Subjects: Hyperactive children -- Psychological testing , Attention-deficit hyperactivity disorder -- Diagnosis , Attention-deficit-disordered children
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9927 , http://hdl.handle.net/10948/655 , Hyperactive children -- Psychological testing , Attention-deficit hyperactivity disorder -- Diagnosis , Attention-deficit-disordered children
- Description: Attention Deficit/Hyperactivity Disorder (AD/HD) is not a new phenomenon. Researchers have studied children with restless, inattentive and impulsive types of behaviours for over one hundred years. Although the primary distress of AD/HD falls mainly on the child’s shoulders, all family members experience the disorder’s negative effects. While the challenges that families have to face are many, families seem to have the ability to “bounce back” (i.e., they have resilience). There has been limited research to date focusing on the resiliency of families living with children diagnosed with AD/HD. Research on the construct of resilience, and more specifically, family resilience has surged in recent times. However, South African research on family resilience is limited. This study aimed to explore and describe the factors that facilitate adjustment and adaptation in families after a child has been clinically diagnosed with AD/HD. The Resiliency Model of Family Stress, Adjustment and Adaptation, developed by McCubbin and McCubbin (2001) served as a framework to conceptualize the families’ adjustment and adaptation processes. Non-probability purposive sampling was used in order to gain participants for the study. Twenty-two families participated in this study, providing a total of 44 participants. Participants consisted of the caregivers of a family living with a child diagnosed with AD/HD, between the ages of seven and 12. The study was triangular in nature, with an exploratory, descriptive approach. A biographical questionnaire with an open-ended question was used in conjunction with seven other questionnaires to gather data. Descriptive statistics were used to describe the biographical information. Quantitative data were analyzed by means of correlation and regression analysis, and content analysis was used to analyze the qualitative data obtained from the biographical questionnaire. The results of the quantitative analysis indicated six significant positive correlations with the FACI8. These variables were relative and friend support, social support, problem solving and behavioural strategies, family hardiness, family problem-solving communication and family time and routines. The results of the qualitative analysis revealed that social support, adherence to a treatment regime, information and knowledge about AD/HD, a supportive family unit, the caregiver’s acceptance of the disorder as well as communication were the most important strength factors identified. The findings of the research could assist parents in managing their children diagnosed with AD/HD more effectively and has helped create further insight into what resiliency areas they could improve upon. Furthermore, this study could be used as a stepping stone for future research on resilience in families living with a pervasive psychological disorder and will contribute to the broader context of family resilience research in the South African context.
- Full Text:
- Date Issued: 2008
Resilience in families with a child living with Autism Spectrum Disorder
- Authors: Hanekom, Leché
- Date: 2008
- Subjects: Autism in children , Parents of autistic children , Autistic children -- Family relationships
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9905 , http://hdl.handle.net/10948/973 , Autism in children , Parents of autistic children , Autistic children -- Family relationships
- Description: In recent years the number of studies on resilience emerging within the field of positive psychology has increased. However, such studies are limited within the South African context and so the proposed study aims to explore and describe the factors that facilitate adjustment and adaptation in South African families living with Autism Spectrum Disorder. McCubbin, McCubbin and Thompson (2001) developed the Resiliency Model of Family Stress, Adjustment and Adaptation which were used to conceptualise the family’s adaptation. Mothers (n = 19) from 19 families participated in the study. The families consisted of at least three members, of which two are parents and one a child younger than 18 years of age that has been diagnosed with Autistic Spectrum Disorder. A combination of non-probability purposive sampling and snowball sampling was used to select participants. The study had an exploratory and descriptive aim and employed triangulation of method, including both qualitative and quantitative data collection procedures. A biographical questionnaire and the following seven structured paper-and-pencil questionnaires were used: the Family Attachment and Changeability Index 8 (FACI8), the Family Crisis-oriented Personal Evaluation Scales (F-COPES), the Family Hardiness Index (FHI), the Family Problem-solving Communication (FPSC), the Family Time and Routine Index (FTRI), the Relative and Friend Support (RFS), and the Social Support Index (SSI). Descriptive statistics were used to describe the biographical information. Qualitative data were analysed by means of content analysis. Quantitative data were manipulated by means of correlation and regression analysis. The results from the quantitative analysis indicate three significant positive correlations with the FACI8. These variables were the family hardiness (measured by FHI), family problem-solving communication (measured by the FPSC), and family time and routines (measured by the FTRI). The findings from the qualitative analysis point out that social support, the spousal relationship and family time, togetherness and routines are the most important strength factors that contribute to the family’s adjustment and adaptation. Even though this study had a small sample size and several other limitations, the findings of this study could still assist in guiding specialised institutions toward providing more comprehensive information and support to families living with a child diagnosed with Autism Spectrum Disorder. This study also contributes to the studies on family resilience within a South African context.
- Full Text:
- Date Issued: 2008
- Authors: Hanekom, Leché
- Date: 2008
- Subjects: Autism in children , Parents of autistic children , Autistic children -- Family relationships
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9905 , http://hdl.handle.net/10948/973 , Autism in children , Parents of autistic children , Autistic children -- Family relationships
- Description: In recent years the number of studies on resilience emerging within the field of positive psychology has increased. However, such studies are limited within the South African context and so the proposed study aims to explore and describe the factors that facilitate adjustment and adaptation in South African families living with Autism Spectrum Disorder. McCubbin, McCubbin and Thompson (2001) developed the Resiliency Model of Family Stress, Adjustment and Adaptation which were used to conceptualise the family’s adaptation. Mothers (n = 19) from 19 families participated in the study. The families consisted of at least three members, of which two are parents and one a child younger than 18 years of age that has been diagnosed with Autistic Spectrum Disorder. A combination of non-probability purposive sampling and snowball sampling was used to select participants. The study had an exploratory and descriptive aim and employed triangulation of method, including both qualitative and quantitative data collection procedures. A biographical questionnaire and the following seven structured paper-and-pencil questionnaires were used: the Family Attachment and Changeability Index 8 (FACI8), the Family Crisis-oriented Personal Evaluation Scales (F-COPES), the Family Hardiness Index (FHI), the Family Problem-solving Communication (FPSC), the Family Time and Routine Index (FTRI), the Relative and Friend Support (RFS), and the Social Support Index (SSI). Descriptive statistics were used to describe the biographical information. Qualitative data were analysed by means of content analysis. Quantitative data were manipulated by means of correlation and regression analysis. The results from the quantitative analysis indicate three significant positive correlations with the FACI8. These variables were the family hardiness (measured by FHI), family problem-solving communication (measured by the FPSC), and family time and routines (measured by the FTRI). The findings from the qualitative analysis point out that social support, the spousal relationship and family time, togetherness and routines are the most important strength factors that contribute to the family’s adjustment and adaptation. Even though this study had a small sample size and several other limitations, the findings of this study could still assist in guiding specialised institutions toward providing more comprehensive information and support to families living with a child diagnosed with Autism Spectrum Disorder. This study also contributes to the studies on family resilience within a South African context.
- Full Text:
- Date Issued: 2008
Resilience in HIV/AIDS' adolescent headed families
- Authors: Beeka, Hershilla A
- Date: 2008
- Subjects: Resilience (Personality trait) in adolescence -- South Africa -- Port Elizabeth , Children of AIDS patients -- South Africa -- Family relationships , Families, Black -- Research -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9911 , http://hdl.handle.net/10948/922 , Resilience (Personality trait) in adolescence -- South Africa -- Port Elizabeth , Children of AIDS patients -- South Africa -- Family relationships , Families, Black -- Research -- South Africa
- Description: HIV/AIDS has presented humanity with various challenges, one of which is the manner in which it has affected family structure and patterns. Parental illness and eventual death due to the HIV/AIDS pandemic is escalating. One of the major challenges of HIV/AIDS in southern Africa is the increase in the number of orphaned and vulnerable children. As a result new family forms are emerging such as the "skip-generation" family in which children or adolescent siblings head the family. It is anticipated that HIV/AIDS in South Africa will progressively increase the number of such families. During this time of profound family change, the family as an institution has remained remarkably resilient. The present study utilised the Family Resilience Framework and the Resiliency Model of Family Stress, Adjustment and Adaptation to explore and describe the resilience of HIV/AIDS’ adolescent headed families. A qualitative, exploratory-descriptive research design, which was assessed against Guba’s (1985) model of trustworthiness, was employed and the participants were sampled using non-probability purposive sampling. The Masizakhe Community Project volunteers (an AIDS Community Project in Kwazakhele, Port Elizabeth receiving support from the iThemba AIDS Foundation) assisted in identifying participants according to the predetermined inclusion criteria. The sample consisted of four female, adolescent heads of HIV/AIDS’ affected households, who volunteered at the Masizakhe Community Project and resided in Kwazakhele. The data that was collected via audio-recorded semi structured interviews were transcribed verbatim and subjected to Interpretive Phenomenological Analysis. Family resilience factors that emerged included intrafamilial strengths (family cohesion, organisation, hardiness, and adaptability); social support resources (especially from the community project, friends, and community members); family appraisal processes; and problem solving and coping strategies. Extended family support was partial and largely financial. The findings from this study provided insights into the resilience of adolescent-headed families; provided guidance for the development of intervention programmes to assist these families; and affirmed the existing strengths of the families. Furthermore, it has contributed to the research and literature on family resilience and formed the foundation for future research projects.
- Full Text:
- Date Issued: 2008
- Authors: Beeka, Hershilla A
- Date: 2008
- Subjects: Resilience (Personality trait) in adolescence -- South Africa -- Port Elizabeth , Children of AIDS patients -- South Africa -- Family relationships , Families, Black -- Research -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9911 , http://hdl.handle.net/10948/922 , Resilience (Personality trait) in adolescence -- South Africa -- Port Elizabeth , Children of AIDS patients -- South Africa -- Family relationships , Families, Black -- Research -- South Africa
- Description: HIV/AIDS has presented humanity with various challenges, one of which is the manner in which it has affected family structure and patterns. Parental illness and eventual death due to the HIV/AIDS pandemic is escalating. One of the major challenges of HIV/AIDS in southern Africa is the increase in the number of orphaned and vulnerable children. As a result new family forms are emerging such as the "skip-generation" family in which children or adolescent siblings head the family. It is anticipated that HIV/AIDS in South Africa will progressively increase the number of such families. During this time of profound family change, the family as an institution has remained remarkably resilient. The present study utilised the Family Resilience Framework and the Resiliency Model of Family Stress, Adjustment and Adaptation to explore and describe the resilience of HIV/AIDS’ adolescent headed families. A qualitative, exploratory-descriptive research design, which was assessed against Guba’s (1985) model of trustworthiness, was employed and the participants were sampled using non-probability purposive sampling. The Masizakhe Community Project volunteers (an AIDS Community Project in Kwazakhele, Port Elizabeth receiving support from the iThemba AIDS Foundation) assisted in identifying participants according to the predetermined inclusion criteria. The sample consisted of four female, adolescent heads of HIV/AIDS’ affected households, who volunteered at the Masizakhe Community Project and resided in Kwazakhele. The data that was collected via audio-recorded semi structured interviews were transcribed verbatim and subjected to Interpretive Phenomenological Analysis. Family resilience factors that emerged included intrafamilial strengths (family cohesion, organisation, hardiness, and adaptability); social support resources (especially from the community project, friends, and community members); family appraisal processes; and problem solving and coping strategies. Extended family support was partial and largely financial. The findings from this study provided insights into the resilience of adolescent-headed families; provided guidance for the development of intervention programmes to assist these families; and affirmed the existing strengths of the families. Furthermore, it has contributed to the research and literature on family resilience and formed the foundation for future research projects.
- Full Text:
- Date Issued: 2008
Resilience in remarried families
- Authors: Robinson, Julie
- Date: 2008
- Subjects: Remarried people -- Family relationships , Adjustment (Psychology) , Stepfamilies -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9924 , http://hdl.handle.net/10948/659 , Remarried people -- Family relationships , Adjustment (Psychology) , Stepfamilies -- Psychological aspects
- Description: Remarried families are no longer the exception in society. Statistics reveal that this type of family structure is increasing. The need for family resilience research in varying family forms has been highlighted. Given the distinctive structure of the remarried family, there are specific dilemmas and challenges that need to be resolved on the journey towards family integration. Despite these challenges, many families benefit from their new family structure and show marked resiliency and ability to adapt. South African family resilience research is scarce. This study aimed to identify, explore and describe the resiliency factors that enable families to adjust and adapt as a result of being a stepfamily. The Resiliency Model of Family Stress, Adjustment and Adaptation (McCubbin, Thompson, & McCubbin, 2001) was used to conceptualize level of adaptation. Participants consisted of both adults and adolescents, in order to gain perspectives of adapting to a remarried family from differing individual family members’ stages of development. Participants consisted of 19 parents and 16 adolescents, equaling a total of 35 participants. Triangulation was employed, with an exploratory, descriptive approach. A biographical questionnaire with an open-ended question, in conjunction with a number of structured questionnaires were used to gather the data. These questionnaires were: The Family Hardiness Index (FHI), the Family Time and Routine Index (FTRI), the Social Support Index (SSI), the Family Problem-Solving Communication (FPSC) Index, the Family Crisis-Oriented Personal Evaluation Scales (F-COPES), the Relative and Friend Support Index (RFS), and the Family Attachment and Changeability Index 8 (FACI8). In this study the FACI8 was used as a measure to determine the level of family adaptation. Non-probability purposive and snowball sampling techniques were used. Descriptive statistics were used to analyze the biographical information. Correlation and regression analysis was used to analyze the quantitative data, and content analysis was used to analyze the qualitative data. The results of the quantitative component of the study indicated that there were three significant positive correlations with the FACI8 for both adults and adolescents. These variables were family hardiness (measured by the FHI), family problem solving communication (measured by the FPSC), and family time together and routines (measured by the FTRI). The Social Support subscale of the F-COPES showed a positive correlation with the FACI8 for the adults. The results of the qualitative component of the study revealed that various common themes emerged between the adult and adolescent participants’ responses. These common themes were spirituality; boundaries; respect, love, understanding, compassion and acceptance; communication; flexibility and tolerance; time together, bonding, and routines; and social support. There were four remaining themes that the adults identified as important factors helping them manage being part of a stepfamily. These four remaining themes were equality; forgiveness and acceptance of the past; commitment and being positive; and financial support. The value of the research was discussed. Finally, limitations of the study were discussed, and suggestions were made for future research involving remarried families.
- Full Text:
- Date Issued: 2008
- Authors: Robinson, Julie
- Date: 2008
- Subjects: Remarried people -- Family relationships , Adjustment (Psychology) , Stepfamilies -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9924 , http://hdl.handle.net/10948/659 , Remarried people -- Family relationships , Adjustment (Psychology) , Stepfamilies -- Psychological aspects
- Description: Remarried families are no longer the exception in society. Statistics reveal that this type of family structure is increasing. The need for family resilience research in varying family forms has been highlighted. Given the distinctive structure of the remarried family, there are specific dilemmas and challenges that need to be resolved on the journey towards family integration. Despite these challenges, many families benefit from their new family structure and show marked resiliency and ability to adapt. South African family resilience research is scarce. This study aimed to identify, explore and describe the resiliency factors that enable families to adjust and adapt as a result of being a stepfamily. The Resiliency Model of Family Stress, Adjustment and Adaptation (McCubbin, Thompson, & McCubbin, 2001) was used to conceptualize level of adaptation. Participants consisted of both adults and adolescents, in order to gain perspectives of adapting to a remarried family from differing individual family members’ stages of development. Participants consisted of 19 parents and 16 adolescents, equaling a total of 35 participants. Triangulation was employed, with an exploratory, descriptive approach. A biographical questionnaire with an open-ended question, in conjunction with a number of structured questionnaires were used to gather the data. These questionnaires were: The Family Hardiness Index (FHI), the Family Time and Routine Index (FTRI), the Social Support Index (SSI), the Family Problem-Solving Communication (FPSC) Index, the Family Crisis-Oriented Personal Evaluation Scales (F-COPES), the Relative and Friend Support Index (RFS), and the Family Attachment and Changeability Index 8 (FACI8). In this study the FACI8 was used as a measure to determine the level of family adaptation. Non-probability purposive and snowball sampling techniques were used. Descriptive statistics were used to analyze the biographical information. Correlation and regression analysis was used to analyze the quantitative data, and content analysis was used to analyze the qualitative data. The results of the quantitative component of the study indicated that there were three significant positive correlations with the FACI8 for both adults and adolescents. These variables were family hardiness (measured by the FHI), family problem solving communication (measured by the FPSC), and family time together and routines (measured by the FTRI). The Social Support subscale of the F-COPES showed a positive correlation with the FACI8 for the adults. The results of the qualitative component of the study revealed that various common themes emerged between the adult and adolescent participants’ responses. These common themes were spirituality; boundaries; respect, love, understanding, compassion and acceptance; communication; flexibility and tolerance; time together, bonding, and routines; and social support. There were four remaining themes that the adults identified as important factors helping them manage being part of a stepfamily. These four remaining themes were equality; forgiveness and acceptance of the past; commitment and being positive; and financial support. The value of the research was discussed. Finally, limitations of the study were discussed, and suggestions were made for future research involving remarried families.
- Full Text:
- Date Issued: 2008
Retention of medical doctors in the public health sector: a case study of the Port Elizabeth Hospital complex
- Authors: Guvava, Dorothy Dorica
- Date: 2008
- Subjects: Employee retention -- Port Elizabeth -- South Africa , Physicians -- Job satisfaction -- South Africa -- Port Elizabeth , Hospitals -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8221 , http://hdl.handle.net/10948/976 , Employee retention -- Port Elizabeth -- South Africa , Physicians -- Job satisfaction -- South Africa -- Port Elizabeth , Hospitals -- South Africa -- Port Elizabeth
- Description: The Port Elizabeth (PE) hospital complex is one of the public hospital groups in South Africa facing a critical shortage of medical practitioners, with reference to doctors in particular. In the quest of finding how to retain doctors in the hospital complex, the aims of this research were to survey doctors’ career intentions; to investigate factors that could be contributing to these career intentions so as to uncover some of the reasons why doctors are leaving the public sector; and to identify effective ways in which the government and hospitals might improve retention by pointing out areas that need improvement. The factors that influence doctors’ career intention included income, work conditions, risk of contracting infection, risk of injury at work, hours of work, work load, work related stress, paid leave days, resources, personal growth and development opportunities, ongoing training opportunities, advancement and promotion opportunities, relation with co-workers, relations with supervisor/superiors, and sense of meaning. Findings revealed that even though the tendency to leave’ group (43%) was smaller than the ‘tendency to stay’ (57%), the majority (85%) of those who intended to leave were younger doctors. Despite some significant differences in responses between the two groups, results revealed that both groups were dissatisfied with almost all conditions of work apart from relationships with supervisors and co-workers. To a large extent, both groups revealed that work conditions are better in the private hospitals than in their current hospitals. viii The fact that some doctors could stay in the public hospital sector despite intense dissatisfaction with conditions of work, and despite the perception that that there are better options in the private hospitals could be attributed to the fact that most of these doctors are older and are at their retirement stage . Adding to this is that most of these doctors, who indicated willingness to say, scored high in sense of meaning as a factor influencing their career intention. This research was based on the assumption that there was no retention strategy put in place to solve the problems facing PE hospital complex. However, during this research a strategy was being developed and implemented by the Eastern Cape Department of Health. Therefore, evaluation and recommendations of the strategy are provided in the conclusions of the study. These recommendations relate not only to the implementation of the strategy, but improving it to accommodate all problems currently facing the doctors and finding ways and means of making the strategy sustainable; creating private-public partnerships; focusing on creating a sense of meaning amongst the doctors (especially the younger ones) and focusing on retaining the risk group which was the younger doctors.
- Full Text:
- Date Issued: 2008
- Authors: Guvava, Dorothy Dorica
- Date: 2008
- Subjects: Employee retention -- Port Elizabeth -- South Africa , Physicians -- Job satisfaction -- South Africa -- Port Elizabeth , Hospitals -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8221 , http://hdl.handle.net/10948/976 , Employee retention -- Port Elizabeth -- South Africa , Physicians -- Job satisfaction -- South Africa -- Port Elizabeth , Hospitals -- South Africa -- Port Elizabeth
- Description: The Port Elizabeth (PE) hospital complex is one of the public hospital groups in South Africa facing a critical shortage of medical practitioners, with reference to doctors in particular. In the quest of finding how to retain doctors in the hospital complex, the aims of this research were to survey doctors’ career intentions; to investigate factors that could be contributing to these career intentions so as to uncover some of the reasons why doctors are leaving the public sector; and to identify effective ways in which the government and hospitals might improve retention by pointing out areas that need improvement. The factors that influence doctors’ career intention included income, work conditions, risk of contracting infection, risk of injury at work, hours of work, work load, work related stress, paid leave days, resources, personal growth and development opportunities, ongoing training opportunities, advancement and promotion opportunities, relation with co-workers, relations with supervisor/superiors, and sense of meaning. Findings revealed that even though the tendency to leave’ group (43%) was smaller than the ‘tendency to stay’ (57%), the majority (85%) of those who intended to leave were younger doctors. Despite some significant differences in responses between the two groups, results revealed that both groups were dissatisfied with almost all conditions of work apart from relationships with supervisors and co-workers. To a large extent, both groups revealed that work conditions are better in the private hospitals than in their current hospitals. viii The fact that some doctors could stay in the public hospital sector despite intense dissatisfaction with conditions of work, and despite the perception that that there are better options in the private hospitals could be attributed to the fact that most of these doctors are older and are at their retirement stage . Adding to this is that most of these doctors, who indicated willingness to say, scored high in sense of meaning as a factor influencing their career intention. This research was based on the assumption that there was no retention strategy put in place to solve the problems facing PE hospital complex. However, during this research a strategy was being developed and implemented by the Eastern Cape Department of Health. Therefore, evaluation and recommendations of the strategy are provided in the conclusions of the study. These recommendations relate not only to the implementation of the strategy, but improving it to accommodate all problems currently facing the doctors and finding ways and means of making the strategy sustainable; creating private-public partnerships; focusing on creating a sense of meaning amongst the doctors (especially the younger ones) and focusing on retaining the risk group which was the younger doctors.
- Full Text:
- Date Issued: 2008
Retention strategies for skilled SARS customs employees
- Authors: Lennie, Graeme Mark
- Date: 2008
- Subjects: Employee retention , Employee motivation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8704 , http://hdl.handle.net/10948/999 , Employee retention , Employee motivation
- Description: The South African Revenue Services (SARS) is an amalgamation of the former Departments of Customs and Excise, and the Receiver of Revenue. SARS obtained full autonomy from the Government in October 1997 in order for it to administer its own affairs. SARS has since made great strides in transforming its people and technology, although some growing pains are recently being experienced, i.e. the “retention question”. The problem statement, “What strategies can be implemented for retaining skilled employees within SARS Customs” is derived from a multitude of problematic issues currently being experienced world wide. Problem areas particular to South Africa, include: the mass exodus of white skilled labour; baby-boomers (aged 60 – 65) nearing retirement, affirmative action, employment equity, and a general lack of skills in the employment industry. An employee engagement survey (2007) conducted at SARS, shows figures that further exacerbates the problem. The objectives of the research were therefore, to conduct a literature study of employee retention strategies, investigate the research strategies currently being employed at SARS, the reasons for the low levels of employee engagement and to develop a strategic model for employee retention for use at SARS Customs in the Eastern Cape Region of South Africa The study takes the form of a case study, using quantitative and qualitative methods of research. A questionnaire was distributed to respondents, the results of which were analysed and presented. The findings show that SARS Customs is in a good position with regards to pay and benefits. Areas that require attention though are training, development and career management, effective supervision, and day-to-day activities.
- Full Text:
- Date Issued: 2008
- Authors: Lennie, Graeme Mark
- Date: 2008
- Subjects: Employee retention , Employee motivation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8704 , http://hdl.handle.net/10948/999 , Employee retention , Employee motivation
- Description: The South African Revenue Services (SARS) is an amalgamation of the former Departments of Customs and Excise, and the Receiver of Revenue. SARS obtained full autonomy from the Government in October 1997 in order for it to administer its own affairs. SARS has since made great strides in transforming its people and technology, although some growing pains are recently being experienced, i.e. the “retention question”. The problem statement, “What strategies can be implemented for retaining skilled employees within SARS Customs” is derived from a multitude of problematic issues currently being experienced world wide. Problem areas particular to South Africa, include: the mass exodus of white skilled labour; baby-boomers (aged 60 – 65) nearing retirement, affirmative action, employment equity, and a general lack of skills in the employment industry. An employee engagement survey (2007) conducted at SARS, shows figures that further exacerbates the problem. The objectives of the research were therefore, to conduct a literature study of employee retention strategies, investigate the research strategies currently being employed at SARS, the reasons for the low levels of employee engagement and to develop a strategic model for employee retention for use at SARS Customs in the Eastern Cape Region of South Africa The study takes the form of a case study, using quantitative and qualitative methods of research. A questionnaire was distributed to respondents, the results of which were analysed and presented. The findings show that SARS Customs is in a good position with regards to pay and benefits. Areas that require attention though are training, development and career management, effective supervision, and day-to-day activities.
- Full Text:
- Date Issued: 2008
School principals' perceptions and responses to the HIV and AIDS pandemic in schools in the Eastern Cape
- Authors: Mahabeer, Pryah
- Date: 2008
- Subjects: AIDS (Disease) -- Study and teaching (Secondary) -- South Africa , HIV (Viruses) -- Study and teaching (Secondary) -- South Africa , School principals -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9532 , http://hdl.handle.net/10948/738 , AIDS (Disease) -- Study and teaching (Secondary) -- South Africa , HIV (Viruses) -- Study and teaching (Secondary) -- South Africa , School principals -- South Africa -- Attitudes
- Description: HIV and AIDS are casting a dark shadow over the future of many developing countries in the world. Since the first diagnosis of AIDS cases, South Africa has become one of the countries most infected with the HIV and AIDS pandemic, with about five million people living with HIV and AIDS. HIV prevalence is high in the age group 15 to 49 years, attacking people in the most productive years of their lives, Africans are the most significant racial group, affected and the Eastern Cape rates sixth in terms of HIV prevalence in the country. Demographically, HIV and AIDS affects the structure of the population, including learner and educator populations, as HIV and AIDS impact on the demand and supply of education. Schools are negatively and diversely impacted by the new challenges of the pandemic, preventing schools from achieving their goals. South Africa is struggling with a shortage of educators in the school system, especially the key areas of science and mathematics. The number of potential learners is expected to decline as AIDS orphans and other vulnerable children drop out of school, relocate, do not enrol, or are forced to withdraw from the school system. These factors lead to a poor morale and unproductivity among educators and learners, causing management problems in education for school principals and a decline in the quality and efficiency of education. While there is still no known cure for HIV and AIDS, the only solution in curbing the spread of the pandemic is through education and changing the social behaviours and mindset of people. However, HIV and AIDS prevention interventions have clearly been ineffective, as infection rates are soaring. As HIV and AIDS infection rates escalates, a more urgent response by school principals is needed to address the unique demands of the pandemic and establish where HIV and AIDS interventions will be most successful. The current study had three major aims. The aims were to explore how school principals in the Eastern Cape perceive the HIV and AIDS pandemic; describe in detail how school principals in the Eastern Cape respond to the HIV and AIDS pandemic; and to formulate recommendations based on the findings of the research that will assist school principals in effectively managing the pandemic at school level. The sample consisted of twelve school principals from different schools in the urban areas of Nelson Mandela Bay and the rural Keiskammahoek area. A qualitative method was selected to capture the unique experiences of school principals. In-depth, unstructured interviews were conducted to gather information. Thereafter, the interviews were transcribed verbatim, analysed and interpreted to gain a deeper understanding of the research phenomenon. The findings of the study revealed that the majority of school principals had limited knowledge only of the HIV and AIDS pandemic, and perceived the pandemic in a non-constructive manner, as an imminent future problem. In fact, many school principals were ambiguous, contradictory and discriminatory in their discussion in their responses to the pandemic, first denying the presence of AIDS cases in their schools, then shifting the blame for the spread of HIV and AIDS in their schools to others. These school principals were clearly unaware that they were being discriminatory and secretive about the pandemic through denial and blaming others and that their attitudes were fuelling stigmatization and discrimination. The school principals acknowledged that much more still needed to be done in terms of management and leadership to effectively mitigate the effects of the pandemic in their schools. While school principals did their best in dealing with HIV and AIDS related problems at their schools, they clearly lacked the necessary skills, training and knowledge to devise long-term strategies to deal effectively and pro-actively with the problems related to the pandemic. Therefore a more transformational leadership and management approach is required by school principals in dealing with the pandemic in their schools, in order to render them effective leaders.
- Full Text:
- Date Issued: 2008
- Authors: Mahabeer, Pryah
- Date: 2008
- Subjects: AIDS (Disease) -- Study and teaching (Secondary) -- South Africa , HIV (Viruses) -- Study and teaching (Secondary) -- South Africa , School principals -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9532 , http://hdl.handle.net/10948/738 , AIDS (Disease) -- Study and teaching (Secondary) -- South Africa , HIV (Viruses) -- Study and teaching (Secondary) -- South Africa , School principals -- South Africa -- Attitudes
- Description: HIV and AIDS are casting a dark shadow over the future of many developing countries in the world. Since the first diagnosis of AIDS cases, South Africa has become one of the countries most infected with the HIV and AIDS pandemic, with about five million people living with HIV and AIDS. HIV prevalence is high in the age group 15 to 49 years, attacking people in the most productive years of their lives, Africans are the most significant racial group, affected and the Eastern Cape rates sixth in terms of HIV prevalence in the country. Demographically, HIV and AIDS affects the structure of the population, including learner and educator populations, as HIV and AIDS impact on the demand and supply of education. Schools are negatively and diversely impacted by the new challenges of the pandemic, preventing schools from achieving their goals. South Africa is struggling with a shortage of educators in the school system, especially the key areas of science and mathematics. The number of potential learners is expected to decline as AIDS orphans and other vulnerable children drop out of school, relocate, do not enrol, or are forced to withdraw from the school system. These factors lead to a poor morale and unproductivity among educators and learners, causing management problems in education for school principals and a decline in the quality and efficiency of education. While there is still no known cure for HIV and AIDS, the only solution in curbing the spread of the pandemic is through education and changing the social behaviours and mindset of people. However, HIV and AIDS prevention interventions have clearly been ineffective, as infection rates are soaring. As HIV and AIDS infection rates escalates, a more urgent response by school principals is needed to address the unique demands of the pandemic and establish where HIV and AIDS interventions will be most successful. The current study had three major aims. The aims were to explore how school principals in the Eastern Cape perceive the HIV and AIDS pandemic; describe in detail how school principals in the Eastern Cape respond to the HIV and AIDS pandemic; and to formulate recommendations based on the findings of the research that will assist school principals in effectively managing the pandemic at school level. The sample consisted of twelve school principals from different schools in the urban areas of Nelson Mandela Bay and the rural Keiskammahoek area. A qualitative method was selected to capture the unique experiences of school principals. In-depth, unstructured interviews were conducted to gather information. Thereafter, the interviews were transcribed verbatim, analysed and interpreted to gain a deeper understanding of the research phenomenon. The findings of the study revealed that the majority of school principals had limited knowledge only of the HIV and AIDS pandemic, and perceived the pandemic in a non-constructive manner, as an imminent future problem. In fact, many school principals were ambiguous, contradictory and discriminatory in their discussion in their responses to the pandemic, first denying the presence of AIDS cases in their schools, then shifting the blame for the spread of HIV and AIDS in their schools to others. These school principals were clearly unaware that they were being discriminatory and secretive about the pandemic through denial and blaming others and that their attitudes were fuelling stigmatization and discrimination. The school principals acknowledged that much more still needed to be done in terms of management and leadership to effectively mitigate the effects of the pandemic in their schools. While school principals did their best in dealing with HIV and AIDS related problems at their schools, they clearly lacked the necessary skills, training and knowledge to devise long-term strategies to deal effectively and pro-actively with the problems related to the pandemic. Therefore a more transformational leadership and management approach is required by school principals in dealing with the pandemic in their schools, in order to render them effective leaders.
- Full Text:
- Date Issued: 2008
Selective para-funtionalization of phenol
- Authors: Indurkar, Jayant R
- Date: 2008
- Subjects: Phenol
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:10402 , http://hdl.handle.net/10948/710 , Phenol
- Description: In previous work done in our laboratories, a method was discovered to produce phenolic mono-ethers from 4-hydroxyacetophenone and other 4-hydroxyketones by treating with ammonium peroxy-disulfate in an alcohol as a reaction solvent and in the presence of concentrated sulphuric acid or other strong protonic acids. Since this method of producing 4-alkoxyphenol ethers provides a very convenient way to modify hydroquinone and substituted hydroquinones to produce a variety of phenol mono-ethers, it was of interest to study the general scope of this reaction, including a more detailed investigation of the reaction mechanism. In previous studies, it was suggested that interaction between the aromatic pi-system of hydroquinone and the cyclohexa-2,5-diene structure of benzoquinone plays a significant role during the reaction. It was therefore of interest to investigate whether other compounds that are also capable of forming the cyclohexa-2,5-diene structure, will interact in a manner analogous to the hydroquinone/benzoquinone couple. Two specific compounds were selected for this purpose, namely 4-nitrosophenol and 4- (diphenylmethylene)cyclohexa-2,5-dien-1-one . The scope of etherification reactions of hydroquinone-benzoquinone or hydroquinone/benzoquinone like substrates such as 4-nitrosophenol and 4- (diphenylmethylene)cyclohexa-2,5-dien-1-one in the presence of acid catalyst and alcohols was investigated. These studies showed that hydroquinone, 4- nitrosophenol and 4-(diphenylmethylene)cyclohexa-2,5-dien-1-one successfully affords the phenolic ethers in good to excellent yield. For example, quantitative yield of 4-methoxyphenol could be obtained from a 1:1 mixture of hydroquinone and benzoquinone at the reflux temperature of methanol. In order to study the reaction mechanism, the cross-over reaction between tertbutylhydroquinone and benzoquinone (or hydroquinone and tertbutylbenzoquinone) was studied in detail. The results of these cross-over reactions were used to propose a mechanistic pathway that could explain the requirement for pi-interaction between the hydroquinone and benzoquinone molecules, the role of the acid catalyst, as well as the relative rates of hydroquinone and benzoquinone consumption during these reactions. The mechanism was also capable of explaining all the reaction products observed during these reactions. The work was then extended to reactions of 4-nitrosophenol and 4- (diphenylmethylene)cyclohexa-2,5-dien-1-one with methanol in the presence of either hydroquinone or benzoquinone. The results of these investigations strongly suggest the presence of similar interactions between these molecules that also influence the outcome of the reactions. The exploitation of pi-interactions between two molecules of these types investigated during this work opens an interesting field of chemistry. Clearly, the level of understanding developed during this work is only beginning to address this interesting field of chemistry and much work will need to be done to gain a fuller understanding of the chemistry involved as well as the potential synthetic value of these interactions.
- Full Text:
- Date Issued: 2008
- Authors: Indurkar, Jayant R
- Date: 2008
- Subjects: Phenol
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:10402 , http://hdl.handle.net/10948/710 , Phenol
- Description: In previous work done in our laboratories, a method was discovered to produce phenolic mono-ethers from 4-hydroxyacetophenone and other 4-hydroxyketones by treating with ammonium peroxy-disulfate in an alcohol as a reaction solvent and in the presence of concentrated sulphuric acid or other strong protonic acids. Since this method of producing 4-alkoxyphenol ethers provides a very convenient way to modify hydroquinone and substituted hydroquinones to produce a variety of phenol mono-ethers, it was of interest to study the general scope of this reaction, including a more detailed investigation of the reaction mechanism. In previous studies, it was suggested that interaction between the aromatic pi-system of hydroquinone and the cyclohexa-2,5-diene structure of benzoquinone plays a significant role during the reaction. It was therefore of interest to investigate whether other compounds that are also capable of forming the cyclohexa-2,5-diene structure, will interact in a manner analogous to the hydroquinone/benzoquinone couple. Two specific compounds were selected for this purpose, namely 4-nitrosophenol and 4- (diphenylmethylene)cyclohexa-2,5-dien-1-one . The scope of etherification reactions of hydroquinone-benzoquinone or hydroquinone/benzoquinone like substrates such as 4-nitrosophenol and 4- (diphenylmethylene)cyclohexa-2,5-dien-1-one in the presence of acid catalyst and alcohols was investigated. These studies showed that hydroquinone, 4- nitrosophenol and 4-(diphenylmethylene)cyclohexa-2,5-dien-1-one successfully affords the phenolic ethers in good to excellent yield. For example, quantitative yield of 4-methoxyphenol could be obtained from a 1:1 mixture of hydroquinone and benzoquinone at the reflux temperature of methanol. In order to study the reaction mechanism, the cross-over reaction between tertbutylhydroquinone and benzoquinone (or hydroquinone and tertbutylbenzoquinone) was studied in detail. The results of these cross-over reactions were used to propose a mechanistic pathway that could explain the requirement for pi-interaction between the hydroquinone and benzoquinone molecules, the role of the acid catalyst, as well as the relative rates of hydroquinone and benzoquinone consumption during these reactions. The mechanism was also capable of explaining all the reaction products observed during these reactions. The work was then extended to reactions of 4-nitrosophenol and 4- (diphenylmethylene)cyclohexa-2,5-dien-1-one with methanol in the presence of either hydroquinone or benzoquinone. The results of these investigations strongly suggest the presence of similar interactions between these molecules that also influence the outcome of the reactions. The exploitation of pi-interactions between two molecules of these types investigated during this work opens an interesting field of chemistry. Clearly, the level of understanding developed during this work is only beginning to address this interesting field of chemistry and much work will need to be done to gain a fuller understanding of the chemistry involved as well as the potential synthetic value of these interactions.
- Full Text:
- Date Issued: 2008
South African police service deploys its first peacekeepers to Darfur, Sudan : a descriptive study on the deployment preparations and the role of the South African police peacekeepers in African union mission in Sudan (AMIS)
- Authors: Mokhine, Ntime Samson
- Date: 2008
- Subjects: Peacekeeping forces , Conflict management
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: vital:8214 , http://hdl.handle.net/10948/1027 , Peacekeeping forces , Conflict management
- Description: The focus of this research will be on the question as to whether the South African Police Service adequately prepares its police officials for the functions they will be performing in Sudan: Darfur. This broad question leads to further questions that include the following: What are the peacekeeping recruitment and selection criteria for the South African Police Service members who need to be deployed in Sudan: Darfur? Is the South African Police Service peacekeeping training curriculum adequate enough to prepare its members for their deployment in Sudan: Darfur? Does the South African Police Service have any measures to evaluate the role played by its members in Sudan: Dafur? What measures have been introduced to utilise the new skills brought by members that have been deployed? Are there any properly posted members with mission experience, who are capable of presenting and further developing peacekeeping training in the South African Police Service? Does the South African Police Service senior management have knowledge of generic peacekeeping concepts?.
- Full Text:
- Date Issued: 2008
- Authors: Mokhine, Ntime Samson
- Date: 2008
- Subjects: Peacekeeping forces , Conflict management
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: vital:8214 , http://hdl.handle.net/10948/1027 , Peacekeeping forces , Conflict management
- Description: The focus of this research will be on the question as to whether the South African Police Service adequately prepares its police officials for the functions they will be performing in Sudan: Darfur. This broad question leads to further questions that include the following: What are the peacekeeping recruitment and selection criteria for the South African Police Service members who need to be deployed in Sudan: Darfur? Is the South African Police Service peacekeeping training curriculum adequate enough to prepare its members for their deployment in Sudan: Darfur? Does the South African Police Service have any measures to evaluate the role played by its members in Sudan: Dafur? What measures have been introduced to utilise the new skills brought by members that have been deployed? Are there any properly posted members with mission experience, who are capable of presenting and further developing peacekeeping training in the South African Police Service? Does the South African Police Service senior management have knowledge of generic peacekeeping concepts?.
- Full Text:
- Date Issued: 2008