Molecular studies on cholera and non-cholera causing vibrio pathogens isolated from some water resources and aquatic animals in Eastern Cape Province, South Africa
- Authors: Abioye, Oluwatayo Emmanuel
- Date: 2018
- Subjects: Vibrio cholerae -- Pathogens Vibrio cholerae
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9154 , vital:34283
- Description: The global socioeconomic and disease burdens of cholera; a disease caused by Vibrio cholerae have been ongoing since it was first reported in India in 1563. Unfortunately, emerging non-cholera causing Vibrio pathogens have been contributing to the malady of Vibrio genus globally in the recent years. The history of cholera outbreaks in South Africa have been well documented but information regarding other non-cholera Vibrio pathogens, is deficient in the literature. This study evaluated the statuses of aquatic animals including crustaceans, molluscs, and fish as important reservoirs of six key pathogenic Vibrio spp. in some important water resources and fish markets in the Eastern Cape, South Africa, between December 2016 and November 2017. Physiochemical parameters that are vital for water quality assessment were determined for all the water sampling points using standard methods. The parameters include pH, electrical conductivity (EC), total dissolved solids (TDS), salinity, temperature, total dissolved solids, turbidity and biological oxygen demand (BOD5). Vibrio spp. densities in water and aquatic animal samples were determined using membrane filtration and Most Probable NumberPolymerase chain reaction (MPN-PCR) methods respectively. Presumptive Vibrio spp. were recovered from the samples by direct plating of water samples and aliquots of aquatic animal homogenates on thiosulfate-citrate-bile salts-sucrose (TCBS) agar. Where necessary, samples were enriched using alkaline peptone water (APW) for optimum isolation of the targeted Vibrio spp. Presumptive isolates were identified and delineated into the six targeted pathogenic Vibrio spp. using PCR method. The antibiogram fingerprint of selected Vibrio spp. against a panel 18 panels of antibacterial agents were also carried out. Multiple antibiotic resistance phenotypes (MARPs) per set of isolates from water sampling sites and aquatic animal types were determined. Finally, multiple antibiotic resistance indices (MARI) for isolates recovered from the samples were determined. All experiments were done in replicate and data compared using one-way analysis of variance and one-tail t-test as appropriate. Correlation and regression analysis were also carried out as appropriate. Uncontrolled agricultural, industrial and domestic wastewater influxes, as well as run-off intrusions into the water resources investigated, were observed throughout the sampling season. The physicochemical qualities of the water resources varied with seasons. While pH observed for all the water sampling sites complied with South Africa and international standards, most sampling sites did not comply with set standards for one or more of the remaining physicochemical parameters. The parameters that frequently exhibited significant correlation and regression with Vibrio spp. densities were TDS, TSS, turbidity and temperature. The densities of Vibrio spp. in the samples studied varied with season and the highest density per sample types were observed in the summer. The prevalence of Vibrio spp. in freshwater, brackish water and aquatic animal samples were 79 percent, 78 percent and 86 percent respectively. The respective prevalence of V. cholerae, V. mimicus, V. fluvialis, V.alginolyticus, V. vulnificus and V. parahaemolyticus in freshwater samples (18 percent, 3 percent, ~1 percent, ~1 percent, <1 percent, < percent), brackish water(12 percent, 3 percent, 28 percent,~1 percent, ~1 percent, 9 percent) and aquatic animals (9 percent, 1 percent, 17 percent, 1 percent, 1 percent, 17 percent) were observed. All isolates from all the sample types showed very high antibiotic resistance against ampicillin and polymyxin B. Furthermore, MARPs were observed among isolates from the three sample types. Multiple antibiotic resistance indices (MARI) above 0.2 was observed at one site on Kowie River, three on Kubusi River and one on Buffalo River. The findings of this study suggest that most South Africa water-bodies especially freshwater resources are not well protected. This need to be addressed in a country like South Africa where availability of the freshwater resource for human activities is a critical issue. Base on the prevalence of pathogenic Vibrio spp. especially MARPs and sites that exhibited above 0.2 threshold for MARI, environmental base Vibrio species monitoring programs are recommended.
- Full Text:
- Date Issued: 2018
- Authors: Abioye, Oluwatayo Emmanuel
- Date: 2018
- Subjects: Vibrio cholerae -- Pathogens Vibrio cholerae
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9154 , vital:34283
- Description: The global socioeconomic and disease burdens of cholera; a disease caused by Vibrio cholerae have been ongoing since it was first reported in India in 1563. Unfortunately, emerging non-cholera causing Vibrio pathogens have been contributing to the malady of Vibrio genus globally in the recent years. The history of cholera outbreaks in South Africa have been well documented but information regarding other non-cholera Vibrio pathogens, is deficient in the literature. This study evaluated the statuses of aquatic animals including crustaceans, molluscs, and fish as important reservoirs of six key pathogenic Vibrio spp. in some important water resources and fish markets in the Eastern Cape, South Africa, between December 2016 and November 2017. Physiochemical parameters that are vital for water quality assessment were determined for all the water sampling points using standard methods. The parameters include pH, electrical conductivity (EC), total dissolved solids (TDS), salinity, temperature, total dissolved solids, turbidity and biological oxygen demand (BOD5). Vibrio spp. densities in water and aquatic animal samples were determined using membrane filtration and Most Probable NumberPolymerase chain reaction (MPN-PCR) methods respectively. Presumptive Vibrio spp. were recovered from the samples by direct plating of water samples and aliquots of aquatic animal homogenates on thiosulfate-citrate-bile salts-sucrose (TCBS) agar. Where necessary, samples were enriched using alkaline peptone water (APW) for optimum isolation of the targeted Vibrio spp. Presumptive isolates were identified and delineated into the six targeted pathogenic Vibrio spp. using PCR method. The antibiogram fingerprint of selected Vibrio spp. against a panel 18 panels of antibacterial agents were also carried out. Multiple antibiotic resistance phenotypes (MARPs) per set of isolates from water sampling sites and aquatic animal types were determined. Finally, multiple antibiotic resistance indices (MARI) for isolates recovered from the samples were determined. All experiments were done in replicate and data compared using one-way analysis of variance and one-tail t-test as appropriate. Correlation and regression analysis were also carried out as appropriate. Uncontrolled agricultural, industrial and domestic wastewater influxes, as well as run-off intrusions into the water resources investigated, were observed throughout the sampling season. The physicochemical qualities of the water resources varied with seasons. While pH observed for all the water sampling sites complied with South Africa and international standards, most sampling sites did not comply with set standards for one or more of the remaining physicochemical parameters. The parameters that frequently exhibited significant correlation and regression with Vibrio spp. densities were TDS, TSS, turbidity and temperature. The densities of Vibrio spp. in the samples studied varied with season and the highest density per sample types were observed in the summer. The prevalence of Vibrio spp. in freshwater, brackish water and aquatic animal samples were 79 percent, 78 percent and 86 percent respectively. The respective prevalence of V. cholerae, V. mimicus, V. fluvialis, V.alginolyticus, V. vulnificus and V. parahaemolyticus in freshwater samples (18 percent, 3 percent, ~1 percent, ~1 percent, <1 percent, < percent), brackish water(12 percent, 3 percent, 28 percent,~1 percent, ~1 percent, 9 percent) and aquatic animals (9 percent, 1 percent, 17 percent, 1 percent, 1 percent, 17 percent) were observed. All isolates from all the sample types showed very high antibiotic resistance against ampicillin and polymyxin B. Furthermore, MARPs were observed among isolates from the three sample types. Multiple antibiotic resistance indices (MARI) above 0.2 was observed at one site on Kowie River, three on Kubusi River and one on Buffalo River. The findings of this study suggest that most South Africa water-bodies especially freshwater resources are not well protected. This need to be addressed in a country like South Africa where availability of the freshwater resource for human activities is a critical issue. Base on the prevalence of pathogenic Vibrio spp. especially MARPs and sites that exhibited above 0.2 threshold for MARI, environmental base Vibrio species monitoring programs are recommended.
- Full Text:
- Date Issued: 2018
Rural-urban migration and its impact on rural development in Nigeria
- Authors: Abizu, Odion Stanley
- Date: 2018
- Subjects: Rural development Rural-urban migration -- Nigeria Rural poor
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/13815 , vital:39714
- Description: This thesis focuses on the developmental impact of rural-urban migration in Nigeria. While, recognising the negative impact of rural-urban migration, the study argues that in order to benefit internal migrants as well as rural development, there must be a paradigm shift to focus on how the benefits of migration on development can be achieved. It is proposed that rural-urban migration occurs as a response to economic, education, health, social and environmental factors. The challenges confronting rural areas are urban bias development paradigm pursued by the successive governments resulting in rural underdevelopment that exacerbates the rural urban disparity. And the neglect of agriculture in rural areas resulting from the discovery of oil in Nigeria. The study revealed that flawed policies adopted by successive Nigerian governments led to joblessness, entrenched social inequality and opportunities. One of the outcomes of these short-sighted policies was rural underdevelopment, which accelerated rural-urban migration in Nigeria. However, the study also demonstrates that the income flows from the migrants to the various rural households has contributed to improvement in the living standard of the households. The fragmentary approaches to rural development that is currently the case in Nigeria would not generate the required level of development and growth needed in the rural communities to improve the living standard. Thus, there is need for a policy framework in Nigeria, which would encourage the private sector to play a vital role in contributing their part in the provision of infrastructural facilities in the rural communities. Although this thesis is a case study of the impact of rural-urban migration on rural development in Nigeria, it can serve to appreciate the role migration can play in promoting development both in rural and urban areas in Nigeria and other Saharan Africa countries.
- Full Text:
- Date Issued: 2018
- Authors: Abizu, Odion Stanley
- Date: 2018
- Subjects: Rural development Rural-urban migration -- Nigeria Rural poor
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/13815 , vital:39714
- Description: This thesis focuses on the developmental impact of rural-urban migration in Nigeria. While, recognising the negative impact of rural-urban migration, the study argues that in order to benefit internal migrants as well as rural development, there must be a paradigm shift to focus on how the benefits of migration on development can be achieved. It is proposed that rural-urban migration occurs as a response to economic, education, health, social and environmental factors. The challenges confronting rural areas are urban bias development paradigm pursued by the successive governments resulting in rural underdevelopment that exacerbates the rural urban disparity. And the neglect of agriculture in rural areas resulting from the discovery of oil in Nigeria. The study revealed that flawed policies adopted by successive Nigerian governments led to joblessness, entrenched social inequality and opportunities. One of the outcomes of these short-sighted policies was rural underdevelopment, which accelerated rural-urban migration in Nigeria. However, the study also demonstrates that the income flows from the migrants to the various rural households has contributed to improvement in the living standard of the households. The fragmentary approaches to rural development that is currently the case in Nigeria would not generate the required level of development and growth needed in the rural communities to improve the living standard. Thus, there is need for a policy framework in Nigeria, which would encourage the private sector to play a vital role in contributing their part in the provision of infrastructural facilities in the rural communities. Although this thesis is a case study of the impact of rural-urban migration on rural development in Nigeria, it can serve to appreciate the role migration can play in promoting development both in rural and urban areas in Nigeria and other Saharan Africa countries.
- Full Text:
- Date Issued: 2018
Impacts of climate change on food security in southern Ghana : a community perspective
- Authors: Aboagye, Dickson Danso
- Date: 2014
- Subjects: Sustainable agriculture -- Ghana , Climatic changes -- Ghana , Food security -- Ghana
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9182 , http://hdl.handle.net/10948/d1020166
- Description: This study will examine the impacts of climate change on food security in Southern Ghana. Southern Ghana reveals that the district suffers post- harvest losses of about 8 percent of all cereals which hinders Ghana’s food security. Ghana still faces food insecurity due to high temperatures and low rainfall. This research therefore seeks to investigate what local communities of Southern Ghana are doing to address food insecurity problems with the advent of climate change. Several objectives to achieve this goal involves to identify factors hindering food security in Southern Ghana and to evaluate the extent that climate change has affected food security. A qualitative research approach was used by the researcher to come up with community strategies which this research seeks to address. Various conclusions such as community demand for support from the local government, sustainable irrigation programs, availability of pipe-borne water and environmental education were put in place, as possible solutions to the persisting food security problems in Southern Ghana.
- Full Text:
- Date Issued: 2014
- Authors: Aboagye, Dickson Danso
- Date: 2014
- Subjects: Sustainable agriculture -- Ghana , Climatic changes -- Ghana , Food security -- Ghana
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9182 , http://hdl.handle.net/10948/d1020166
- Description: This study will examine the impacts of climate change on food security in Southern Ghana. Southern Ghana reveals that the district suffers post- harvest losses of about 8 percent of all cereals which hinders Ghana’s food security. Ghana still faces food insecurity due to high temperatures and low rainfall. This research therefore seeks to investigate what local communities of Southern Ghana are doing to address food insecurity problems with the advent of climate change. Several objectives to achieve this goal involves to identify factors hindering food security in Southern Ghana and to evaluate the extent that climate change has affected food security. A qualitative research approach was used by the researcher to come up with community strategies which this research seeks to address. Various conclusions such as community demand for support from the local government, sustainable irrigation programs, availability of pipe-borne water and environmental education were put in place, as possible solutions to the persisting food security problems in Southern Ghana.
- Full Text:
- Date Issued: 2014
Strengths that contribute towards resilience in the early years of marriage
- Authors: Aboagye, Lauren Lee
- Date: 2012
- Subjects: Marriage -- Interpersonal relations , Marriage -- Religious aspects -- Christianity , Resilience (Personality trait) , Communication in marriage , Adjustment (Psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9983 , http://hdl.handle.net/10948/1667 , Marriage -- Interpersonal relations , Marriage -- Religious aspects -- Christianity , Resilience (Personality trait) , Communication in marriage , Adjustment (Psychology)
- Description: Divorce is a common phenomenon in South Africa, affecting many families across the country. On the other hand, there are many couples who choose to remain married, despite having endured significant stress. In a review of literature there have been studies conducted exploring enduring marriages (marriages that have lasted twenty years or more), but little on resilience in the early years of marriage. With many couples choosing to divorce within the first ten years of marriage, there is value in exploring the strengths of young marriages that contribute towards resilience. The following question then arises: what are the stressors that couples experience during the early years of marriage (under ten years) and how does the way they cope with these challenges enhance resilience in their marriages? This question has resulted in this qualitative study, employing an exploratory descriptive and contextual research design with the aim of exploring the strengths that contribute towards resilience in the early years of marriage. The study is based within the framework of positive psychology, as this facilitates the exploration of the factors that have contributed towards the resilience of the couples that were interviewed. A non-probability, purposive sampling technique was employed to obtain research participants. Data was collected through the use of individual semistructured interviews conducted with five couples (ten individuals) who have been married for ten years or less, have endured significant stress, have chosen to remain married, and experience their relationship as satisfying. The interviews were recorded, transcribed and analysed using thematic content analysis. The results of the study may be used to develop a strengths based-intervention programme for couples in the early years of marriage.
- Full Text:
- Date Issued: 2012
- Authors: Aboagye, Lauren Lee
- Date: 2012
- Subjects: Marriage -- Interpersonal relations , Marriage -- Religious aspects -- Christianity , Resilience (Personality trait) , Communication in marriage , Adjustment (Psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9983 , http://hdl.handle.net/10948/1667 , Marriage -- Interpersonal relations , Marriage -- Religious aspects -- Christianity , Resilience (Personality trait) , Communication in marriage , Adjustment (Psychology)
- Description: Divorce is a common phenomenon in South Africa, affecting many families across the country. On the other hand, there are many couples who choose to remain married, despite having endured significant stress. In a review of literature there have been studies conducted exploring enduring marriages (marriages that have lasted twenty years or more), but little on resilience in the early years of marriage. With many couples choosing to divorce within the first ten years of marriage, there is value in exploring the strengths of young marriages that contribute towards resilience. The following question then arises: what are the stressors that couples experience during the early years of marriage (under ten years) and how does the way they cope with these challenges enhance resilience in their marriages? This question has resulted in this qualitative study, employing an exploratory descriptive and contextual research design with the aim of exploring the strengths that contribute towards resilience in the early years of marriage. The study is based within the framework of positive psychology, as this facilitates the exploration of the factors that have contributed towards the resilience of the couples that were interviewed. A non-probability, purposive sampling technique was employed to obtain research participants. Data was collected through the use of individual semistructured interviews conducted with five couples (ten individuals) who have been married for ten years or less, have endured significant stress, have chosen to remain married, and experience their relationship as satisfying. The interviews were recorded, transcribed and analysed using thematic content analysis. The results of the study may be used to develop a strengths based-intervention programme for couples in the early years of marriage.
- Full Text:
- Date Issued: 2012
Prevalence of Escherichia coli O157:H7 in water and meat and meat products and vegetables sold in the Eastern Cape Province of South Africa and its impact on the diarrhoeic conditions of HIV/AIDS patients
- Authors: Abong'o, Benard Omondi
- Date: 2008
- Subjects: Foodborne diseases , Diarrhea , Escherichia coli , HIV infections , AIDS (Disease) , Bacterial diseases
- Language: English
- Type: Thesis , Doctoral , PhD (Microbiology)
- Identifier: vital:11263 , http://hdl.handle.net/10353/87 , Foodborne diseases , Diarrhea , Escherichia coli , HIV infections , AIDS (Disease) , Bacterial diseases
- Description: Water and food borne Escherichia coli O157:H7 could be one of the pathogens posing high health risk to patients suffering from Acquired Immunodeficiency Syndrome (AIDS) because of its incrimination in diarrhoea cases in AIDS patients. The present study, which was conducted between March 2005 and August 2006, investigated the prevalence of E. coli O157:H7 in water, meat and meat products and vegetables and its impact on diarrhoeic conditions of confirmed and non-confirmed HIV/AIDS patients in the Amathole District in the Eastern Cape Province of South Africa. The water samples used in the study were obtained from stand pipes supplying treated drinking water to communities residing in Fort Beaufort, Alice, Dimbaza and Mdantsane whereas borehole waters were sampled from Ngwenya and Kwasaki. The meat and meat products and vegetable samples were purchased from shops, butcheries, supermarkets and open air markets in Fort Beaufort, Alice and Mdantsane. The stool swabs used in the study were obtained from HIV/AIDS and outpatient clinics at Frere Hospital in East London. A total of 180 each of water, meat and meat products and vegetable samples and another 360 stool samples were analyzed for E. coli O157:H7. Presumptive E. coli O157 was isolated from the samples by culture-based methods and confirmed using Polymerase Chain Reaction techniques. Anti-biogram as well as risk assessment were also carried out using standard methods. The viable counts of presumptive E. coli O157 for water samples ranged between 3.3 × 104 and 1.71 × 105 CFU/ml, and between 1.8 × 104 and 5.04 × 106 CFU/g for meat and meat products, whereas those for vegetables ranged between 1.3 × 103 and 1.6 × 106 CFU/g. The counts of presumptive E. coli O157 for the water and vegetable samples were not significantly different whereas those for meat and meat products were found to be significantly different (P ≤ 0.05). The prevalence rates of presumptive E coli O157 in meat and meat products was 35.55 percent (64/180), and 25.55 percent (46/180) and 21.66 percent (39/180) for water and vegetables respectively. Prevalence of presumptive E. coli O157 in the stool samples of HIV/AIDS patients was 36.39 percent (131/360), of which 56.5 percent (74/131) and 43.5 percent (57/131) were from stools of confirmed and non-confirmed HIV/AIDS patients, respectively. Molecular analysis of representative presumptive E. coli O157 indicated that 10.29 percent (4/39) of vegetables; 14.81 percent (4/27) of water and 38.46 percent (5/13) of meat and meat products carried E. coli O157:H7. Also 36 percent (9/25) and 17.24 percent (5/29) of the stool samples were positive for E. coli O157:H7. Antimicrobial susceptibility profile revealed that all of the E. coli O157:H7 isolated from water, meat and meat products and vegetables as well as those isolated from stools of confirmed and non-confirmed HIV/AIDS patients were resistant (R) to gentamycin and erythromycin. However, 75 percent (20/27) of these isolates were resistant (R) to ampicillin and tetracycline whereas approximately 25 percent (6/27) were resistant (R) to nalidixic acid, ceftriaxone, and chloramphenicol. All the isolates (27/27) were susceptible (S) to amikacin. Probability of risk of E. coli O157:H7 infection was high for confirmed HIV/AIDS patients than for the non-confirmed HIV/AIDS patients. Estimated probability of risk of E. coli O157:H7 due to ingestion of water was 1.00 for 100 confirmed and non-confirmed HIV/AIDS patients. Risk due to meat and meat products was estimated at 0.27 and 0.20 and for vegetables at 0.21 and 0.15 per 100 confirmed and non-confirmed HIV/AIDS patients. The findings of this study predicted a possible link between E. coli O157:H7 isolated from drinking water, meat and meat products and vegetables and diarrhoeic conditions in both confirmed and non-confirmed HIV/AIDS patients, and concludes that confirmed HIV/AIDS patients can be at higher risk of contracting water and food borne E. coli O157:H7 than nonconfirmed HIV/AIDS patients. It is thus recommended that proper water treatment and food handling, maximum food and water safety and sanitation as well as personal body hygiene should be maintained, in order to prevent E. coli O157:H7 infections. Education initiatives and active surveillance of E. coli O157:H7 should be taken by all the stake-holders working directly or indirectly towards ensuring enduring sound public health.
- Full Text:
- Date Issued: 2008
- Authors: Abong'o, Benard Omondi
- Date: 2008
- Subjects: Foodborne diseases , Diarrhea , Escherichia coli , HIV infections , AIDS (Disease) , Bacterial diseases
- Language: English
- Type: Thesis , Doctoral , PhD (Microbiology)
- Identifier: vital:11263 , http://hdl.handle.net/10353/87 , Foodborne diseases , Diarrhea , Escherichia coli , HIV infections , AIDS (Disease) , Bacterial diseases
- Description: Water and food borne Escherichia coli O157:H7 could be one of the pathogens posing high health risk to patients suffering from Acquired Immunodeficiency Syndrome (AIDS) because of its incrimination in diarrhoea cases in AIDS patients. The present study, which was conducted between March 2005 and August 2006, investigated the prevalence of E. coli O157:H7 in water, meat and meat products and vegetables and its impact on diarrhoeic conditions of confirmed and non-confirmed HIV/AIDS patients in the Amathole District in the Eastern Cape Province of South Africa. The water samples used in the study were obtained from stand pipes supplying treated drinking water to communities residing in Fort Beaufort, Alice, Dimbaza and Mdantsane whereas borehole waters were sampled from Ngwenya and Kwasaki. The meat and meat products and vegetable samples were purchased from shops, butcheries, supermarkets and open air markets in Fort Beaufort, Alice and Mdantsane. The stool swabs used in the study were obtained from HIV/AIDS and outpatient clinics at Frere Hospital in East London. A total of 180 each of water, meat and meat products and vegetable samples and another 360 stool samples were analyzed for E. coli O157:H7. Presumptive E. coli O157 was isolated from the samples by culture-based methods and confirmed using Polymerase Chain Reaction techniques. Anti-biogram as well as risk assessment were also carried out using standard methods. The viable counts of presumptive E. coli O157 for water samples ranged between 3.3 × 104 and 1.71 × 105 CFU/ml, and between 1.8 × 104 and 5.04 × 106 CFU/g for meat and meat products, whereas those for vegetables ranged between 1.3 × 103 and 1.6 × 106 CFU/g. The counts of presumptive E. coli O157 for the water and vegetable samples were not significantly different whereas those for meat and meat products were found to be significantly different (P ≤ 0.05). The prevalence rates of presumptive E coli O157 in meat and meat products was 35.55 percent (64/180), and 25.55 percent (46/180) and 21.66 percent (39/180) for water and vegetables respectively. Prevalence of presumptive E. coli O157 in the stool samples of HIV/AIDS patients was 36.39 percent (131/360), of which 56.5 percent (74/131) and 43.5 percent (57/131) were from stools of confirmed and non-confirmed HIV/AIDS patients, respectively. Molecular analysis of representative presumptive E. coli O157 indicated that 10.29 percent (4/39) of vegetables; 14.81 percent (4/27) of water and 38.46 percent (5/13) of meat and meat products carried E. coli O157:H7. Also 36 percent (9/25) and 17.24 percent (5/29) of the stool samples were positive for E. coli O157:H7. Antimicrobial susceptibility profile revealed that all of the E. coli O157:H7 isolated from water, meat and meat products and vegetables as well as those isolated from stools of confirmed and non-confirmed HIV/AIDS patients were resistant (R) to gentamycin and erythromycin. However, 75 percent (20/27) of these isolates were resistant (R) to ampicillin and tetracycline whereas approximately 25 percent (6/27) were resistant (R) to nalidixic acid, ceftriaxone, and chloramphenicol. All the isolates (27/27) were susceptible (S) to amikacin. Probability of risk of E. coli O157:H7 infection was high for confirmed HIV/AIDS patients than for the non-confirmed HIV/AIDS patients. Estimated probability of risk of E. coli O157:H7 due to ingestion of water was 1.00 for 100 confirmed and non-confirmed HIV/AIDS patients. Risk due to meat and meat products was estimated at 0.27 and 0.20 and for vegetables at 0.21 and 0.15 per 100 confirmed and non-confirmed HIV/AIDS patients. The findings of this study predicted a possible link between E. coli O157:H7 isolated from drinking water, meat and meat products and vegetables and diarrhoeic conditions in both confirmed and non-confirmed HIV/AIDS patients, and concludes that confirmed HIV/AIDS patients can be at higher risk of contracting water and food borne E. coli O157:H7 than nonconfirmed HIV/AIDS patients. It is thus recommended that proper water treatment and food handling, maximum food and water safety and sanitation as well as personal body hygiene should be maintained, in order to prevent E. coli O157:H7 infections. Education initiatives and active surveillance of E. coli O157:H7 should be taken by all the stake-holders working directly or indirectly towards ensuring enduring sound public health.
- Full Text:
- Date Issued: 2008
Effect of processing on the efficacy and safety of Solanum Aculeastrum Dunal berries
- Authors: Aboyade, Oluwaseyi Mayode
- Date: 2009
- Subjects: Medicinal plants -- South Africa -- Eastern Cape , Plant extracts , Drugs -- Effectiveness , Berries , Solanum , Solanum Aculeastrum -- Effectiveness
- Language: English
- Type: Thesis , Doctoral , PhD (Botany)
- Identifier: vital:11302 , http://hdl.handle.net/10353/d1001051 , Medicinal plants -- South Africa -- Eastern Cape , Plant extracts , Drugs -- Effectiveness , Berries , Solanum , Solanum Aculeastrum -- Effectiveness
- Description: General Abstract There has been a steady increase in the use of medicinal plants in the last two decades in both developed and developing countries for prevention, management and treatment of diseases. This increase has been due to reasons such as ease of access, better cultural acceptability and compatibility, cost effectiveness and also the bid to “go natural”. Unfortunately, the notion that herbal medicines are relatively safe because they are natural has led to serious and potentially fatal consequences in phytotherapy. The lack of rigorous research to prove the effectiveness and safety of many medicinal plants is of great concern to the health care system. This thesis therefore addresses not just the efficacy, but also the safety of the extracts of the berry of Solanum aculeastrum - a medicinal plant used, among other things, for the treatment of breast cancer in the Eastern Cape Province of South Africa. Particular attention was paid to the possible effect of different processing methods of the berry extracts on inflammation, cytotoxicity, and toxicity. In studying the comparative effects of various processing methods, four different preparations of the extracts were investigated. These include fresh, dried, boiled fresh, and boiled dried berries. While the effect of processing on the anti-inflammatory properties of the extracts was not dose dependent, the percentage reduction in inflammation was highly significant and more prominent in both concentrations of the boiled fresh berries than the reference drug, indomethacin. Furthermore, the four extracts varied in their ability to act either centrally or peripherally in their effect on pain. Assessment of the analgesic response using the formalin test showed that, at both concentrations tested, none of the extracts inhibited the first phase of the formalin test. Furthermore, it was observed that boiling had differing results on the activity of the iii fresh and dried extracts. While boiling of the dried berries reduced pain in the rats, the opposite trend was observed with the boiled fresh berries. Results of the influence of processing of the berries on cytotoxicity indicated that the extracts are potent inhibitors of human breast, cervical and colonic carcinoma cells and the non-cancerous cells (both the actively dividing and confluent Chang liver cells). Although, in terms of relative potency, the fresh berries appeared to be the most active of the extracts, processing of the berries caused an increase in apoptotic cells and a subsequent decrease in the necrotic cells. The effect of processing on the safety of the berry of S. aculeastrum on the rats fed for 28 days was also investigated. The various doses (1, 10 and 25 mg/kg body weight) of all the four extracts did not alter the activity and the weight of the animals throughout the period of treatment. A reduction in organ to body weight ratio of the heart, kidney, liver and spleen was observed in all the extracts. Regarding the haematological parameters, different patterns of effect were observed between the extracts and within the treated doses. The observed alterations in the biochemical parameters by the various extract of Solanum aculeastrum berries at all the doses may have consequential effects on the normal functioning of these organs. In conclusion, this study has shown that there is some justification for the traditional use of the berries of Solanum aculeastrum in the treatment of inflammation related ailments and cancer. However, the medicinal use of the plant also poses considerable health risks. Investigation conducted into the plant’s safety revealed that the berry extracts were nephrotoxic, hepatotoxic, haematotoxic and at higher doses, fatal. Another concern with regard to the plant’s safety is the non-selectivity of its extracts in the inhibition of carcinoma, actively dividing and un-dividing cells. Assessment of the effect of the processing on the berry’s efficacy and safety as herbal iv remedy produced mixed results. On the one hand, processing seemed to improve the extract’s anti-inflammatory and analgesic activity, while reducing its cytotoxic potential. On the other hand, a reduction in the toxicity was observed on the processed extracts compared to the fresh ones. This may be an indication that processing has an overall beneficial effect on the medicinal properties of the plant and should thus be considered as a method of making the berries of Solanum aculeastrum safer for use as a herbal remedy.
- Full Text:
- Date Issued: 2009
- Authors: Aboyade, Oluwaseyi Mayode
- Date: 2009
- Subjects: Medicinal plants -- South Africa -- Eastern Cape , Plant extracts , Drugs -- Effectiveness , Berries , Solanum , Solanum Aculeastrum -- Effectiveness
- Language: English
- Type: Thesis , Doctoral , PhD (Botany)
- Identifier: vital:11302 , http://hdl.handle.net/10353/d1001051 , Medicinal plants -- South Africa -- Eastern Cape , Plant extracts , Drugs -- Effectiveness , Berries , Solanum , Solanum Aculeastrum -- Effectiveness
- Description: General Abstract There has been a steady increase in the use of medicinal plants in the last two decades in both developed and developing countries for prevention, management and treatment of diseases. This increase has been due to reasons such as ease of access, better cultural acceptability and compatibility, cost effectiveness and also the bid to “go natural”. Unfortunately, the notion that herbal medicines are relatively safe because they are natural has led to serious and potentially fatal consequences in phytotherapy. The lack of rigorous research to prove the effectiveness and safety of many medicinal plants is of great concern to the health care system. This thesis therefore addresses not just the efficacy, but also the safety of the extracts of the berry of Solanum aculeastrum - a medicinal plant used, among other things, for the treatment of breast cancer in the Eastern Cape Province of South Africa. Particular attention was paid to the possible effect of different processing methods of the berry extracts on inflammation, cytotoxicity, and toxicity. In studying the comparative effects of various processing methods, four different preparations of the extracts were investigated. These include fresh, dried, boiled fresh, and boiled dried berries. While the effect of processing on the anti-inflammatory properties of the extracts was not dose dependent, the percentage reduction in inflammation was highly significant and more prominent in both concentrations of the boiled fresh berries than the reference drug, indomethacin. Furthermore, the four extracts varied in their ability to act either centrally or peripherally in their effect on pain. Assessment of the analgesic response using the formalin test showed that, at both concentrations tested, none of the extracts inhibited the first phase of the formalin test. Furthermore, it was observed that boiling had differing results on the activity of the iii fresh and dried extracts. While boiling of the dried berries reduced pain in the rats, the opposite trend was observed with the boiled fresh berries. Results of the influence of processing of the berries on cytotoxicity indicated that the extracts are potent inhibitors of human breast, cervical and colonic carcinoma cells and the non-cancerous cells (both the actively dividing and confluent Chang liver cells). Although, in terms of relative potency, the fresh berries appeared to be the most active of the extracts, processing of the berries caused an increase in apoptotic cells and a subsequent decrease in the necrotic cells. The effect of processing on the safety of the berry of S. aculeastrum on the rats fed for 28 days was also investigated. The various doses (1, 10 and 25 mg/kg body weight) of all the four extracts did not alter the activity and the weight of the animals throughout the period of treatment. A reduction in organ to body weight ratio of the heart, kidney, liver and spleen was observed in all the extracts. Regarding the haematological parameters, different patterns of effect were observed between the extracts and within the treated doses. The observed alterations in the biochemical parameters by the various extract of Solanum aculeastrum berries at all the doses may have consequential effects on the normal functioning of these organs. In conclusion, this study has shown that there is some justification for the traditional use of the berries of Solanum aculeastrum in the treatment of inflammation related ailments and cancer. However, the medicinal use of the plant also poses considerable health risks. Investigation conducted into the plant’s safety revealed that the berry extracts were nephrotoxic, hepatotoxic, haematotoxic and at higher doses, fatal. Another concern with regard to the plant’s safety is the non-selectivity of its extracts in the inhibition of carcinoma, actively dividing and un-dividing cells. Assessment of the effect of the processing on the berry’s efficacy and safety as herbal iv remedy produced mixed results. On the one hand, processing seemed to improve the extract’s anti-inflammatory and analgesic activity, while reducing its cytotoxic potential. On the other hand, a reduction in the toxicity was observed on the processed extracts compared to the fresh ones. This may be an indication that processing has an overall beneficial effect on the medicinal properties of the plant and should thus be considered as a method of making the berries of Solanum aculeastrum safer for use as a herbal remedy.
- Full Text:
- Date Issued: 2009
Family interaction patterns in maternal alcohol abuse: an application of Murray Bowen's family system theory
- Authors: Abraham, Hanlie
- Date: 2017
- Subjects: Family psychotherapy , Social psychology Bowen, Murray, -- 1913-1990 Women -- Alcohol use Alcoholism -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/13669 , vital:27293
- Description: The aim of this study was to explore and describe the intergenerational interactional patterns in a Coloured family where the mother has abused alcohol. Researchers have found that drinking behaviours of parents can have major effects on the children’s lives throughout generations. Substance abuse of a parent has major influences on the family, their interactions, and relationships, mostly between the parent and the child. There is a major gap in the study of the Coloured families and how substance abuse affects their families and children. The study employed Bowen’s constructs of differentiation of self, multigenerational transmission process, triangulation, emotional cut-off, nuclear family emotional system, sibling position, family projection process, and societal regression and utilized analytical generalization of the concepts to achieve its aim. The mother, an older sibling and maternal mother were the main sources of data although the perspective of the mother herself was privileged in the study. Semi-structured interviews were utilized to gather the data. This allowed participants to freely narrate their personal perceptions and experiences of interaction in both the family of origin and the current nuclear family. The research used a single case study of a purposively sampled family. The researcher is a Coloured female who had specific interest in this specific cultural group and their interactional patterns, which optimised cultural familiarity during the research process and reduced the likelihood of potential discriminatory racial bias of the participants. The findings demonstrate that perceptions of interactional patterns in the nuclear family and family of origin coincided with certain of Bowen’s Family Systems concepts, particularly, triangulation and differentiation. However, the need for further exploration of concepts such as the nuclear family emotional system and the family projection process in Coloured families are still needed in future studies. The findings provided insight into the functioning of the relationships and FAMILY INTERACTION IN MATERNAL ALCOHOL ABUSE interactions in both the nuclear family and the family of origin. Limitations of the current study are identified and recommendations for future studies in this field are also offered.
- Full Text:
- Date Issued: 2017
- Authors: Abraham, Hanlie
- Date: 2017
- Subjects: Family psychotherapy , Social psychology Bowen, Murray, -- 1913-1990 Women -- Alcohol use Alcoholism -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/13669 , vital:27293
- Description: The aim of this study was to explore and describe the intergenerational interactional patterns in a Coloured family where the mother has abused alcohol. Researchers have found that drinking behaviours of parents can have major effects on the children’s lives throughout generations. Substance abuse of a parent has major influences on the family, their interactions, and relationships, mostly between the parent and the child. There is a major gap in the study of the Coloured families and how substance abuse affects their families and children. The study employed Bowen’s constructs of differentiation of self, multigenerational transmission process, triangulation, emotional cut-off, nuclear family emotional system, sibling position, family projection process, and societal regression and utilized analytical generalization of the concepts to achieve its aim. The mother, an older sibling and maternal mother were the main sources of data although the perspective of the mother herself was privileged in the study. Semi-structured interviews were utilized to gather the data. This allowed participants to freely narrate their personal perceptions and experiences of interaction in both the family of origin and the current nuclear family. The research used a single case study of a purposively sampled family. The researcher is a Coloured female who had specific interest in this specific cultural group and their interactional patterns, which optimised cultural familiarity during the research process and reduced the likelihood of potential discriminatory racial bias of the participants. The findings demonstrate that perceptions of interactional patterns in the nuclear family and family of origin coincided with certain of Bowen’s Family Systems concepts, particularly, triangulation and differentiation. However, the need for further exploration of concepts such as the nuclear family emotional system and the family projection process in Coloured families are still needed in future studies. The findings provided insight into the functioning of the relationships and FAMILY INTERACTION IN MATERNAL ALCOHOL ABUSE interactions in both the nuclear family and the family of origin. Limitations of the current study are identified and recommendations for future studies in this field are also offered.
- Full Text:
- Date Issued: 2017
Photosynthetic and growth response of C₃ and C₄ subspecies of Alloteropsis semialata to nitrogen-supply
- Authors: Abraham, Trevor Ian
- Date: 2008
- Subjects: Photosynthesis , Plants -- Effect of nitrogen on , Growth (Plants) , Plant ecology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4182 , http://hdl.handle.net/10962/d1003750 , Photosynthesis , Plants -- Effect of nitrogen on , Growth (Plants) , Plant ecology
- Description: The greater photosynthetic nitrogen use efficiency (PNUE) of C4 compared with C3 plants may explain the relative success of C4 grasses in nutrient poor environments. This study compared the responses in photosynthetic parameters, leaf nitrogen and biomass allocation between the C3 and C4 subspecies of Alloteropsis semialata supplied soil nitrogen at three levels. Photosynthesis was assessed by means of CO2 response curves and the leaf nitrogen content assayed. Plants were destructively harvested, leaf areas determined and the dry biomass of functional plant components was measured. Results confirmed that the higher PNUE of C4 plants allowed them to accumulate more biomass than C3 plants at the high nitrogen level, despite smaller leaf areas. The greater productivity of C4 plants enabled them to invest more in storage and sexual reproduction than in leaves when compared to the C3 plants. In contrast the C3 plants invested biomass in less efficient and more nitrogen demanding leaves and bigger root systems. PNUE and photosynthetic rates were not significantly affected by nitrogen-limitation in either subspecies and the major response was a decrease in biomass accumulation and an increase in biomass allocation to roots. This altered root to shoot ratio was accompanied by a lowered allocation to sexual reproduction in the C4 subspecies, but an unaltered allocation to leaves, while in the C3 subspecies there was a decrease in leaf allocation. In a further experiment, the C4 subspecies was supplied three levels of nitrogen provided as nitrate, or alternatively as ammonium plus nitrate, and leaves were excised to within 5 cm of the ground at the start of treatment. Prior to flowering, photosynthesis was assessed by means of CO2 response curves and the plants were destructively harvested. Leaf areas and the dry biomass of functional plant components were determined, and at levels of nitrogen supply higher than those found in savanna soils the rate of photosynthesis was increased. Leaf re-growth was reduced by severe nitrogen limitation and co-provision of nitrate and ammonium had no significant effect other than increased tillering. Both subspecies of Alloteropsis semialata are adapted to nutrient poor environments and maintain photosynthetic rates by reducing leaf area. The C4 subspecies is likely to show greater resilience in disturbance-prone environments by exploiting its higher PNUE to allocate greater resources to storage and sexual reproduction, while the C3 subspecies is usually found in environments with closed canopies which favour vegetative growth, and allocate greater resources to leaves and roots.
- Full Text:
- Date Issued: 2008
- Authors: Abraham, Trevor Ian
- Date: 2008
- Subjects: Photosynthesis , Plants -- Effect of nitrogen on , Growth (Plants) , Plant ecology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4182 , http://hdl.handle.net/10962/d1003750 , Photosynthesis , Plants -- Effect of nitrogen on , Growth (Plants) , Plant ecology
- Description: The greater photosynthetic nitrogen use efficiency (PNUE) of C4 compared with C3 plants may explain the relative success of C4 grasses in nutrient poor environments. This study compared the responses in photosynthetic parameters, leaf nitrogen and biomass allocation between the C3 and C4 subspecies of Alloteropsis semialata supplied soil nitrogen at three levels. Photosynthesis was assessed by means of CO2 response curves and the leaf nitrogen content assayed. Plants were destructively harvested, leaf areas determined and the dry biomass of functional plant components was measured. Results confirmed that the higher PNUE of C4 plants allowed them to accumulate more biomass than C3 plants at the high nitrogen level, despite smaller leaf areas. The greater productivity of C4 plants enabled them to invest more in storage and sexual reproduction than in leaves when compared to the C3 plants. In contrast the C3 plants invested biomass in less efficient and more nitrogen demanding leaves and bigger root systems. PNUE and photosynthetic rates were not significantly affected by nitrogen-limitation in either subspecies and the major response was a decrease in biomass accumulation and an increase in biomass allocation to roots. This altered root to shoot ratio was accompanied by a lowered allocation to sexual reproduction in the C4 subspecies, but an unaltered allocation to leaves, while in the C3 subspecies there was a decrease in leaf allocation. In a further experiment, the C4 subspecies was supplied three levels of nitrogen provided as nitrate, or alternatively as ammonium plus nitrate, and leaves were excised to within 5 cm of the ground at the start of treatment. Prior to flowering, photosynthesis was assessed by means of CO2 response curves and the plants were destructively harvested. Leaf areas and the dry biomass of functional plant components were determined, and at levels of nitrogen supply higher than those found in savanna soils the rate of photosynthesis was increased. Leaf re-growth was reduced by severe nitrogen limitation and co-provision of nitrate and ammonium had no significant effect other than increased tillering. Both subspecies of Alloteropsis semialata are adapted to nutrient poor environments and maintain photosynthetic rates by reducing leaf area. The C4 subspecies is likely to show greater resilience in disturbance-prone environments by exploiting its higher PNUE to allocate greater resources to storage and sexual reproduction, while the C3 subspecies is usually found in environments with closed canopies which favour vegetative growth, and allocate greater resources to leaves and roots.
- Full Text:
- Date Issued: 2008
The coordination chemistry of Rhenium(V) with multidentate no-donor ligands
- Authors: Abrahams, Abubak'r
- Date: 2009
- Subjects: Rhenium , Ligands
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10370 , http://hdl.handle.net/10948/912 , Rhenium , Ligands
- Description: The neutral distorted octahedral complexes [ReOCl(L)] {H2L = N,N-bis(2- hydroxybenzyl)-2-(2-aminoethyl)dimethylamine (H2had), N,N-bis(2-hydroxybenzyl) aminomethylpyridine (H2hap); N,N-bis(2-hydroxybenzyl)-2-(2-aminoethyl)pyridine (H2hae)} were prepared by the reaction of trans-[ReOCl3(PPh3)2] with a twofold molar excess of H2L in ethanol. The X-ray structure determinations of [ReOCl(had)] and [ReOCl(hap)] were performed, and in both complexes the chloride is coordinated trans to the tripodal tertiary amino nitrogen, with a phenolate oxygen trans to the oxo oxygen. Treatment of trans-[ReO2(py)4]I with two equivalents and one equivalent each of H2had in acetone afforded the iodide salts of the oxypyridinium-ammonium zwitterions N1-(2-hydroxybenzyl)-N2,N2- dimethyl-N1-((2-oxypyridinium)-1-methyl)ethane-1,2-diamine [Hhpd]+ and N2,N2- dimethyl-N1-bis((2-oxypyridinium)-1-methyl)ethane-1,2-diamine [dod]+ respectively. In [Hhpd]I, one of the 2-hydroxyphenyl groups of H2had is substituted by an oxypyridinium group, and in [dod]I, both 2-hydroxyphenyl groups are converted. The X-ray crystal structure determination of the starting material H2had, [Hhpd]I and [dod]I reveals trigonal pyramidal geometries around the central amino nitrogen. The complex salt [ReO(bsa)]PF6 (H2bsa=bis(N-methylsalicylicylideneiminopropyl) amine) was prepared from the reaction of cis-[ReO2I(PPh3)2] with H2bsa in toluene. The dianionic pentadentate ligand bsa is coordinated to the ReO3+ moiety via one secondary amino and two imino nitrogens, and two anionic phenolate oxygens. The complex was characterized by spectroscopy and analytical data, and the structure has been determined by single-crystal X-ray diffraction analysis. The complex exhibits a distorted octahedral geometry around the central rhenium(V) ion, with the basal plane being defined by a phenolate oxygen, two imino nitrogens and the secondary amino. ix A. Abrahams Nelson Mandela Metropolitan University The reaction of a two-fold molar excess of the potentially NN-donor ligand 2,2’- dipyridylamine (dpa) with trans-[ReO(OEt)Cl2(PPh3)2] in ethanol led to the isolation of [ReOCl2(OEt)(dpa)]. The X-ray crystal structure shows that the NN-chelated dpa is coordinated in the equatorial plane cis to the oxo and ethoxo groups, which are in trans positions relative to each other. The treatment of trans- [ReOCl3(PPh3)2] with a tenfold molar excess of dpa in ethanol at the refluxing temperature yielded the trans-dioxo complex [ReO2(dpa)2]Cl, but with a twofold molar excess only (μ-O)[{ReOCl2(dpa)}2] was isolated. Repeating the latter reaction with (n-Bu4N)[ReOCl4] as starting material in ethanol at room temperature a dark green product, also with the formulation (μ-O)[{ReOCl2(dpa)}2], was isolated. The reaction of equimolar quantities of bis(pyridin-2-yl)methyl)amine (HBPA) with (n-Bu4N)[ReOCl4] in acetone at room temperature led to the isolation of the sixcoordinate rhenium(V) complex [ReOCl(H2O)(BPA)]Cl. IR, NMR and X-ray crystallographic results indicate that BPA is coordinated as a tridentate uninegative chelate, with deprotonation of the amine nitrogen. The water molecule is coordinated trans to the oxo group, with the Re=O and Re-OH2 bond distances equal to 1.663(9) and 2.21(1) Å respectively. Complexes of the general formula [ReOX2{(C5H4N)CH(O)CH2(C5H4N)}] (X = Cl, I) were prepared by the reactions of trans-[ReOCl3(PPh3)2] and trans- [ReOI2(OEt)(PPh3)2] with cis-1,2-di-(2-pyridyl)ethylene (DPE) in ethanol and benzene in air. Experimental evidence shows that the coordinated DPE ligand has undergone addition of water at the ethylenic carbons, and that the (C5H4N)CH(O)CH2(C5H4N) moiety acts as a uninegative tridentate NON-donor ligand. The X-ray crystal structures of both complexes show a distorted octahedral geometry around the rhenium(V) centre. The treatment of trans-[ReOCl3(PPh3)2] with H2dbd in a 2:1 molar ratio in acetonitrile led to the isolation of the ligand-bridged dimer (μ-dbd)[ReOCl2(PPh3)]2. The X-ray crystal structure of the complex reveals a dinuclear structure in which two rhenium(V) ions are bridged by the dbd ligand. Each rhenium ion is in a x A. Abrahams Nelson Mandela Metropolitan University distorted octahedral geometry. The basal plane is defined by a phosphorus atom of the PPh3 group, two chlorides cis to each other, and a pyridyl nitrogen atom of dbd. The oxo group and alcoholate oxygen of dbd lie in trans axial positions. The complexes cis-[ReOX2(msa)(PPh3)] (X = Cl, Br, I) were prepared from trans- [ReOCl3(PPh3)2], trans-[ReOBr3(PPh3)2] or trans-[ReOI2(OEt)(PPh3)2] with 2-(1- iminoethyl)phenol (Hmsa) in acetonitrile. An X-ray crystallographic study shows that the bonding distances and angles in the comlexes are nearly identical, and that the two halides in each complex are coordinated cis to each other in the equatorial plane cis to the oxo group. The oxo-bridged dinuclear rhenium(V) complex [(μ-O){ReOCl(amp)}2] was prepared by the reaction of trans-[ReOCl3(PPh3)2] and 6-amino-3-methyl-1-phenyl- 4-azahept-2-ene-1-one (Hamp) in acetone. The characterization of the complex by elemental analysis, infrared and 1H NMR spectroscopy and X-ray crystallography shows that amp is coordinated as a monoanionic NNO-donor chelate as an amino-amido ketone. However, the reaction of the similar ligand 7- amino-4,7-dimethyl-5-aza-3-octen-2-one (Hada) with [Re(CO)5Br] produced the product fac-[Re(CO)3Br(Hada)], with Hada coordinated as a neutral NN-donor amino-imino-ketone.
- Full Text:
- Date Issued: 2009
- Authors: Abrahams, Abubak'r
- Date: 2009
- Subjects: Rhenium , Ligands
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10370 , http://hdl.handle.net/10948/912 , Rhenium , Ligands
- Description: The neutral distorted octahedral complexes [ReOCl(L)] {H2L = N,N-bis(2- hydroxybenzyl)-2-(2-aminoethyl)dimethylamine (H2had), N,N-bis(2-hydroxybenzyl) aminomethylpyridine (H2hap); N,N-bis(2-hydroxybenzyl)-2-(2-aminoethyl)pyridine (H2hae)} were prepared by the reaction of trans-[ReOCl3(PPh3)2] with a twofold molar excess of H2L in ethanol. The X-ray structure determinations of [ReOCl(had)] and [ReOCl(hap)] were performed, and in both complexes the chloride is coordinated trans to the tripodal tertiary amino nitrogen, with a phenolate oxygen trans to the oxo oxygen. Treatment of trans-[ReO2(py)4]I with two equivalents and one equivalent each of H2had in acetone afforded the iodide salts of the oxypyridinium-ammonium zwitterions N1-(2-hydroxybenzyl)-N2,N2- dimethyl-N1-((2-oxypyridinium)-1-methyl)ethane-1,2-diamine [Hhpd]+ and N2,N2- dimethyl-N1-bis((2-oxypyridinium)-1-methyl)ethane-1,2-diamine [dod]+ respectively. In [Hhpd]I, one of the 2-hydroxyphenyl groups of H2had is substituted by an oxypyridinium group, and in [dod]I, both 2-hydroxyphenyl groups are converted. The X-ray crystal structure determination of the starting material H2had, [Hhpd]I and [dod]I reveals trigonal pyramidal geometries around the central amino nitrogen. The complex salt [ReO(bsa)]PF6 (H2bsa=bis(N-methylsalicylicylideneiminopropyl) amine) was prepared from the reaction of cis-[ReO2I(PPh3)2] with H2bsa in toluene. The dianionic pentadentate ligand bsa is coordinated to the ReO3+ moiety via one secondary amino and two imino nitrogens, and two anionic phenolate oxygens. The complex was characterized by spectroscopy and analytical data, and the structure has been determined by single-crystal X-ray diffraction analysis. The complex exhibits a distorted octahedral geometry around the central rhenium(V) ion, with the basal plane being defined by a phenolate oxygen, two imino nitrogens and the secondary amino. ix A. Abrahams Nelson Mandela Metropolitan University The reaction of a two-fold molar excess of the potentially NN-donor ligand 2,2’- dipyridylamine (dpa) with trans-[ReO(OEt)Cl2(PPh3)2] in ethanol led to the isolation of [ReOCl2(OEt)(dpa)]. The X-ray crystal structure shows that the NN-chelated dpa is coordinated in the equatorial plane cis to the oxo and ethoxo groups, which are in trans positions relative to each other. The treatment of trans- [ReOCl3(PPh3)2] with a tenfold molar excess of dpa in ethanol at the refluxing temperature yielded the trans-dioxo complex [ReO2(dpa)2]Cl, but with a twofold molar excess only (μ-O)[{ReOCl2(dpa)}2] was isolated. Repeating the latter reaction with (n-Bu4N)[ReOCl4] as starting material in ethanol at room temperature a dark green product, also with the formulation (μ-O)[{ReOCl2(dpa)}2], was isolated. The reaction of equimolar quantities of bis(pyridin-2-yl)methyl)amine (HBPA) with (n-Bu4N)[ReOCl4] in acetone at room temperature led to the isolation of the sixcoordinate rhenium(V) complex [ReOCl(H2O)(BPA)]Cl. IR, NMR and X-ray crystallographic results indicate that BPA is coordinated as a tridentate uninegative chelate, with deprotonation of the amine nitrogen. The water molecule is coordinated trans to the oxo group, with the Re=O and Re-OH2 bond distances equal to 1.663(9) and 2.21(1) Å respectively. Complexes of the general formula [ReOX2{(C5H4N)CH(O)CH2(C5H4N)}] (X = Cl, I) were prepared by the reactions of trans-[ReOCl3(PPh3)2] and trans- [ReOI2(OEt)(PPh3)2] with cis-1,2-di-(2-pyridyl)ethylene (DPE) in ethanol and benzene in air. Experimental evidence shows that the coordinated DPE ligand has undergone addition of water at the ethylenic carbons, and that the (C5H4N)CH(O)CH2(C5H4N) moiety acts as a uninegative tridentate NON-donor ligand. The X-ray crystal structures of both complexes show a distorted octahedral geometry around the rhenium(V) centre. The treatment of trans-[ReOCl3(PPh3)2] with H2dbd in a 2:1 molar ratio in acetonitrile led to the isolation of the ligand-bridged dimer (μ-dbd)[ReOCl2(PPh3)]2. The X-ray crystal structure of the complex reveals a dinuclear structure in which two rhenium(V) ions are bridged by the dbd ligand. Each rhenium ion is in a x A. Abrahams Nelson Mandela Metropolitan University distorted octahedral geometry. The basal plane is defined by a phosphorus atom of the PPh3 group, two chlorides cis to each other, and a pyridyl nitrogen atom of dbd. The oxo group and alcoholate oxygen of dbd lie in trans axial positions. The complexes cis-[ReOX2(msa)(PPh3)] (X = Cl, Br, I) were prepared from trans- [ReOCl3(PPh3)2], trans-[ReOBr3(PPh3)2] or trans-[ReOI2(OEt)(PPh3)2] with 2-(1- iminoethyl)phenol (Hmsa) in acetonitrile. An X-ray crystallographic study shows that the bonding distances and angles in the comlexes are nearly identical, and that the two halides in each complex are coordinated cis to each other in the equatorial plane cis to the oxo group. The oxo-bridged dinuclear rhenium(V) complex [(μ-O){ReOCl(amp)}2] was prepared by the reaction of trans-[ReOCl3(PPh3)2] and 6-amino-3-methyl-1-phenyl- 4-azahept-2-ene-1-one (Hamp) in acetone. The characterization of the complex by elemental analysis, infrared and 1H NMR spectroscopy and X-ray crystallography shows that amp is coordinated as a monoanionic NNO-donor chelate as an amino-amido ketone. However, the reaction of the similar ligand 7- amino-4,7-dimethyl-5-aza-3-octen-2-one (Hada) with [Re(CO)5Br] produced the product fac-[Re(CO)3Br(Hada)], with Hada coordinated as a neutral NN-donor amino-imino-ketone.
- Full Text:
- Date Issued: 2009
Isolation, purification and kinetic characterization of prolyl endopeptidase from Titicum aestivum
- Authors: Abrahams, Adriam Mark
- Date: 2013
- Subjects: Endopeptidases , Wheat , Chemical kinetics , Pharmacokinetics
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11269 , http://hdl.handle.net/10353/d1004356 , Endopeptidases , Wheat , Chemical kinetics , Pharmacokinetics
- Description: PEP activity has been described in several locations and has mostly been linked to a variety of neurological disorders such as schizophrenia, amnaesia, depression as well as other disease states such as anorexia nervosa, bulimia nervosa and blood pressure regulation. The enzyme has also been previously isolated from a variety of archae, microorganisms and several eukaryotic species but no prolyl endopeptidases have been isolated from plants. Plants have high levels of proline and glutamine rich peptides in seeds. We therefore hypothesize plants must express PEPs during germination. Bioinformatics tools were used to identify known PEPs and putative plant PEPs. A global sequence alignment of putative plant PEPs and other known PEPs indicated that the active site amino acids Ser, His and Asp are conserved in putative plant PEP sequences. Furthermore, putative plant PEPs showed similar secondary structures to known PEPs and when a rice PEP was modelled onto porcine brain PEP structure, a high degree of similarity was found. Germination studies of wheat seed showed an increase of PEP activity over time with maximum PEP activity reached after 4 days of germination, which remained at this level until 9 days of germination, implying a function for PEP in plant seed germination. Wheat PEP was purified using ion exchange and gel filtration chromatography with a final yield of less than 1 percent and a relative purity (only 2 bands detected by SDS-PAGE). The purified wheat PEP had a molecular weight of approximately 55kDa, substrate specificity for chymotrypsin-like substrates (N-Suc-Ala-Ala-Pro-Phe-pNa, Km value of 0.58 mM, Kcat of 29.37 s–1; Kcat /Km 50813.14s–1 M–1); a pH optimum of 7.9; temperature optima of 37oC and a high sensitivity to temperature as indicated by loss of activity at temperatures above 40oC. Inhibition studies using E64, Leupeptin and PMSF confirmed that the wheat PEP is from the Serine protease family and is most likely a trypsin-like protease.
- Full Text:
- Date Issued: 2013
- Authors: Abrahams, Adriam Mark
- Date: 2013
- Subjects: Endopeptidases , Wheat , Chemical kinetics , Pharmacokinetics
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11269 , http://hdl.handle.net/10353/d1004356 , Endopeptidases , Wheat , Chemical kinetics , Pharmacokinetics
- Description: PEP activity has been described in several locations and has mostly been linked to a variety of neurological disorders such as schizophrenia, amnaesia, depression as well as other disease states such as anorexia nervosa, bulimia nervosa and blood pressure regulation. The enzyme has also been previously isolated from a variety of archae, microorganisms and several eukaryotic species but no prolyl endopeptidases have been isolated from plants. Plants have high levels of proline and glutamine rich peptides in seeds. We therefore hypothesize plants must express PEPs during germination. Bioinformatics tools were used to identify known PEPs and putative plant PEPs. A global sequence alignment of putative plant PEPs and other known PEPs indicated that the active site amino acids Ser, His and Asp are conserved in putative plant PEP sequences. Furthermore, putative plant PEPs showed similar secondary structures to known PEPs and when a rice PEP was modelled onto porcine brain PEP structure, a high degree of similarity was found. Germination studies of wheat seed showed an increase of PEP activity over time with maximum PEP activity reached after 4 days of germination, which remained at this level until 9 days of germination, implying a function for PEP in plant seed germination. Wheat PEP was purified using ion exchange and gel filtration chromatography with a final yield of less than 1 percent and a relative purity (only 2 bands detected by SDS-PAGE). The purified wheat PEP had a molecular weight of approximately 55kDa, substrate specificity for chymotrypsin-like substrates (N-Suc-Ala-Ala-Pro-Phe-pNa, Km value of 0.58 mM, Kcat of 29.37 s–1; Kcat /Km 50813.14s–1 M–1); a pH optimum of 7.9; temperature optima of 37oC and a high sensitivity to temperature as indicated by loss of activity at temperatures above 40oC. Inhibition studies using E64, Leupeptin and PMSF confirmed that the wheat PEP is from the Serine protease family and is most likely a trypsin-like protease.
- Full Text:
- Date Issued: 2013
Political and religious identities : an exploration of changing identities amongst religious leaders in the Northern areas of Port Elizabeth
- Authors: Abrahams, Andre John
- Date: 2014
- Subjects: Religion and politics -- South Africa -- Port Elizabeth , Identification (Religion)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8314 , http://hdl.handle.net/10948/d1020087
- Description: The political transition from the oppressive apartheid system to post-apartheid South Africa has brought considerable change to the political climate. As a result of this transition, political and religious identities were also affected. This study explores the changing identities amongst religious leaders particularly in the Northern Areas of Port Elizabeth. The research has also explored how the advent of democracy has affected the political perspectives of these religious leaders who were ministering during apartheid. A qualitative research approach was used to frame the study, which employed an exploratory research design so as to understand the current political identities of these religious leaders. The sample of the study was purposively selected using the snowball sampling technique. As a means of collecting data in-depth interviews were conducted. The themes emanating from the study were recognised as being: - Church leaders reflecting on the political climate apparent in the Northern Areas of Port Elizabeth - Church leaders reflect reasons for limited political action from certain segments of the community sighting fear and poverty as central tenets. - Church leaders reveal close link between the church and politics during the apartheid period - The activities of the church in opposing the apartheid structure - Participants reflect on the role of Church leaders specifically during this period. - Church leaders articulate their disappointment in the political environment since 1994. - Church leaders reflect how race has affected the political climate since 1994 - The changing role of the church since 1994 - The growing silence on current political issues since 1994 Based on the identified themes conclusions could be drawn on the current political and religious identities of religious leaders compared to those adopted during the apartheid period. The outcome showed that religious leaders within the Northern Areas of Port Elizabeth are disappointed in the current political government but despite this have remained silent on political issues unlike the visible activism and vocal upheaval waged against the apartheid system.
- Full Text:
- Date Issued: 2014
- Authors: Abrahams, Andre John
- Date: 2014
- Subjects: Religion and politics -- South Africa -- Port Elizabeth , Identification (Religion)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8314 , http://hdl.handle.net/10948/d1020087
- Description: The political transition from the oppressive apartheid system to post-apartheid South Africa has brought considerable change to the political climate. As a result of this transition, political and religious identities were also affected. This study explores the changing identities amongst religious leaders particularly in the Northern Areas of Port Elizabeth. The research has also explored how the advent of democracy has affected the political perspectives of these religious leaders who were ministering during apartheid. A qualitative research approach was used to frame the study, which employed an exploratory research design so as to understand the current political identities of these religious leaders. The sample of the study was purposively selected using the snowball sampling technique. As a means of collecting data in-depth interviews were conducted. The themes emanating from the study were recognised as being: - Church leaders reflecting on the political climate apparent in the Northern Areas of Port Elizabeth - Church leaders reflect reasons for limited political action from certain segments of the community sighting fear and poverty as central tenets. - Church leaders reveal close link between the church and politics during the apartheid period - The activities of the church in opposing the apartheid structure - Participants reflect on the role of Church leaders specifically during this period. - Church leaders articulate their disappointment in the political environment since 1994. - Church leaders reflect how race has affected the political climate since 1994 - The changing role of the church since 1994 - The growing silence on current political issues since 1994 Based on the identified themes conclusions could be drawn on the current political and religious identities of religious leaders compared to those adopted during the apartheid period. The outcome showed that religious leaders within the Northern Areas of Port Elizabeth are disappointed in the current political government but despite this have remained silent on political issues unlike the visible activism and vocal upheaval waged against the apartheid system.
- Full Text:
- Date Issued: 2014
The protection against child labour in South Africa
- Authors: Abrahams, Collis
- Date: 2019
- Subjects: Child labor
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10948/40204 , vital:35986
- Description: This treatise seeks to describe the legal protection of children against child labour in South Africa. It does so within the context of international-law-protection in the form of Conventions of the International Labour Organisation. The treatise distinguishes between the concepts of child labour and child work and traces the history of international law prohibiting and regulating child labour. The two most important ILO Conventions, Convention 138 of 1973 and 182 of 1998 are considered in some detail before the national legislature is explained and analysed. From the discussion it is apparent that South Africa is giving effect to the applicable ILO Conventions. Not only does national legislation prohibit child labour, the state also adopted nation-wide programmes to eradicate child labour. Despite the efforts there is still room for improvement. The fight to eradicate child labour must continue!
- Full Text:
- Date Issued: 2019
- Authors: Abrahams, Collis
- Date: 2019
- Subjects: Child labor
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10948/40204 , vital:35986
- Description: This treatise seeks to describe the legal protection of children against child labour in South Africa. It does so within the context of international-law-protection in the form of Conventions of the International Labour Organisation. The treatise distinguishes between the concepts of child labour and child work and traces the history of international law prohibiting and regulating child labour. The two most important ILO Conventions, Convention 138 of 1973 and 182 of 1998 are considered in some detail before the national legislature is explained and analysed. From the discussion it is apparent that South Africa is giving effect to the applicable ILO Conventions. Not only does national legislation prohibit child labour, the state also adopted nation-wide programmes to eradicate child labour. Despite the efforts there is still room for improvement. The fight to eradicate child labour must continue!
- Full Text:
- Date Issued: 2019
The unfair labour practice relating to promotion
- Authors: Abrahams, Dawood
- Date: 2004
- Subjects: Unfair labor practices -- South Africa , Promotions -- South Africa , Labor laws and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11035 , http://hdl.handle.net/10948/329 , Unfair labor practices -- South Africa , Promotions -- South Africa , Labor laws and legislation -- South Africa
- Description: This article deals with the South African law relating to promotions. As promotion disputes mostly arise as alleged unfair labour practices, a short discussion on how the concept of an unfair labour practice developed in South Africa is undertaken. In this regard the common law is studied in order to see whether it makes provision for protection of employees subjected to unfair labour practices relating to promotions. Through this study one soon realises that the common law is in fact inadequate to deal with unfair labour practices relating to promotions, and thus an enquiry into various legislative provisions are undertaken. The impact of the all-important Wiehahn Commission of Enquiry, established in 1979, is also briefly discussed. In this article an attempt is made to define the term ‘promotion’. In this regard reference is made to some cases adjudicated upon by the Commission for Conciliation Mediation and Arbitration (the “CCMA”). The cases referred to seem to favour the view that when one is defining the term ‘promotion’, regard must be had to the employment relationship between the employer and the employee, as well as the nature of the employee’s current work in relation to the work applied for, in order to establish whether in fact a promotion has taken place. It is necessary to consider what unfair conduct is defined as in the context of promotions. It seems that managerial prerogative is at the center of the enquiry into unfair conduct of the employer. Further to the analysis of unfair conduct, various principles that govern both procedural and substantive unfairness are considered. These principles are dealt with separately with reference to case law. Lastly the dispute resolution mechanisms are considered and a brief discussion on remedies is undertaken. The remedies are discussed with reference to case law, as well as the provisions of the Labour Relations Act 66 of 1995 as amended by the Labour Relations Amendment Act 12 of 2002. The broad headings of this article are accordingly unfair labour practices, definition of promotions, unfair conduct of the employer, onus of proof and remedies. It is concluded with the proposition that once an employer has set policies and procedures in place in dealing with promotions, then such an employer should stick to those policies and procedures within the context of the law, as well as within the percepts of the vague and nebulous term of ‘fairness’. Should the employer fail to do so, the majority of cases indicate that such an employer will be guilty of an unfair labour practice relating to promotion.
- Full Text:
- Date Issued: 2004
- Authors: Abrahams, Dawood
- Date: 2004
- Subjects: Unfair labor practices -- South Africa , Promotions -- South Africa , Labor laws and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11035 , http://hdl.handle.net/10948/329 , Unfair labor practices -- South Africa , Promotions -- South Africa , Labor laws and legislation -- South Africa
- Description: This article deals with the South African law relating to promotions. As promotion disputes mostly arise as alleged unfair labour practices, a short discussion on how the concept of an unfair labour practice developed in South Africa is undertaken. In this regard the common law is studied in order to see whether it makes provision for protection of employees subjected to unfair labour practices relating to promotions. Through this study one soon realises that the common law is in fact inadequate to deal with unfair labour practices relating to promotions, and thus an enquiry into various legislative provisions are undertaken. The impact of the all-important Wiehahn Commission of Enquiry, established in 1979, is also briefly discussed. In this article an attempt is made to define the term ‘promotion’. In this regard reference is made to some cases adjudicated upon by the Commission for Conciliation Mediation and Arbitration (the “CCMA”). The cases referred to seem to favour the view that when one is defining the term ‘promotion’, regard must be had to the employment relationship between the employer and the employee, as well as the nature of the employee’s current work in relation to the work applied for, in order to establish whether in fact a promotion has taken place. It is necessary to consider what unfair conduct is defined as in the context of promotions. It seems that managerial prerogative is at the center of the enquiry into unfair conduct of the employer. Further to the analysis of unfair conduct, various principles that govern both procedural and substantive unfairness are considered. These principles are dealt with separately with reference to case law. Lastly the dispute resolution mechanisms are considered and a brief discussion on remedies is undertaken. The remedies are discussed with reference to case law, as well as the provisions of the Labour Relations Act 66 of 1995 as amended by the Labour Relations Amendment Act 12 of 2002. The broad headings of this article are accordingly unfair labour practices, definition of promotions, unfair conduct of the employer, onus of proof and remedies. It is concluded with the proposition that once an employer has set policies and procedures in place in dealing with promotions, then such an employer should stick to those policies and procedures within the context of the law, as well as within the percepts of the vague and nebulous term of ‘fairness’. Should the employer fail to do so, the majority of cases indicate that such an employer will be guilty of an unfair labour practice relating to promotion.
- Full Text:
- Date Issued: 2004
Financial inclusion in South Africa
- Authors: Abrahams, Rayghana
- Date: 2017
- Subjects: Financial services industry -- South Africa , Financial institutions -- South Africa Finance -- South Africa South Africa -- Economic conditions
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/13579 , vital:27240
- Description: The research for this study was guided by the question on whether the financial inclusion improvement strategies of the South African government adequately address the financial inclusion targets, as set out in the National Development Plan. This descriptive non-empirical study was conducted by means of a literature review. The secondary data used for the study were collected from a number of sources, namely: (i) the 2015 Brookings Financial and Digital Inclusion Project report; (ii) the 2014 Global Findex survey; (iii) the InterMedia surveys; (iv) Financial Access surveys; (v) various national FinScope surveys; and (iv) a number of working papers of the World Bank related to financial inclusion. The data revealed that South Africa, with its sophisticated financial sector, was early to adopt policies and initiatives to advance financial inclusion and the country has experienced a noticeable increase in financial inclusion from 61% in 2004 to 87% in 2015. South Africa is 3% away from its National Development Plan goal of 90% financial inclusion by 2030. This indicates that overall, the financial inclusion initiatives adopted by the South African government were successful.
- Full Text:
- Date Issued: 2017
- Authors: Abrahams, Rayghana
- Date: 2017
- Subjects: Financial services industry -- South Africa , Financial institutions -- South Africa Finance -- South Africa South Africa -- Economic conditions
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/13579 , vital:27240
- Description: The research for this study was guided by the question on whether the financial inclusion improvement strategies of the South African government adequately address the financial inclusion targets, as set out in the National Development Plan. This descriptive non-empirical study was conducted by means of a literature review. The secondary data used for the study were collected from a number of sources, namely: (i) the 2015 Brookings Financial and Digital Inclusion Project report; (ii) the 2014 Global Findex survey; (iii) the InterMedia surveys; (iv) Financial Access surveys; (v) various national FinScope surveys; and (iv) a number of working papers of the World Bank related to financial inclusion. The data revealed that South Africa, with its sophisticated financial sector, was early to adopt policies and initiatives to advance financial inclusion and the country has experienced a noticeable increase in financial inclusion from 61% in 2004 to 87% in 2015. South Africa is 3% away from its National Development Plan goal of 90% financial inclusion by 2030. This indicates that overall, the financial inclusion initiatives adopted by the South African government were successful.
- Full Text:
- Date Issued: 2017
Understanding of biological teleology from a naturalistic perspective
- Authors: Abrahams, Sanaa
- Date: 2020
- Subjects: Teleology , Biology -- Philosophy , Evolution (Biology) -- Philosophy
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/140534 , vital:37896
- Description: To the extent that teleological thinking is metaphysically suspect, many theorists attempt to shift the stigma of functional explanations by reducing function ascriptions, and aim thus to de-legitimise an appeal to teleological causal relations in an analysis of function. The point is to dispel the mystery which envelops the application of function concepts by reformulating biological functional explanations so as to dispense with teleology. My project is to interrogate the success with which teleological explanations have thus been eliminated in the biological sciences, and, over the course of this thesis, I conclude that a kind of teleological causation nevertheless remains the most adequate explanatory ground of natural products. My proposal is that functional explanations are causal explanations for the presence and maintenance of self-reproducing systems. I contend that, insofar as the attribution of function presupposes the valuation of a function-bearing system as a causal necessity for its constituent parts, functional explanation references distinct and irreducible holistic properties. Using Kantian metaphysics to frame the discussion, this thesis aims first to explore critically the subject of functional characterisations of biological phenomena, and second, the metaphysical basis of modern science. Its chief contributions to the philosophical function debate reside in proposing novel arguments in justification of what I consider is an improved formulation of an attempted definition of biological function, in which teleological causal powers are explicitly recognised and accommodated in functional explanation. Moreover, this thesis attempts a naturalistic reconstruction of the metaphysical entailments of the real causality of a whole
- Full Text:
- Date Issued: 2020
- Authors: Abrahams, Sanaa
- Date: 2020
- Subjects: Teleology , Biology -- Philosophy , Evolution (Biology) -- Philosophy
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/140534 , vital:37896
- Description: To the extent that teleological thinking is metaphysically suspect, many theorists attempt to shift the stigma of functional explanations by reducing function ascriptions, and aim thus to de-legitimise an appeal to teleological causal relations in an analysis of function. The point is to dispel the mystery which envelops the application of function concepts by reformulating biological functional explanations so as to dispense with teleology. My project is to interrogate the success with which teleological explanations have thus been eliminated in the biological sciences, and, over the course of this thesis, I conclude that a kind of teleological causation nevertheless remains the most adequate explanatory ground of natural products. My proposal is that functional explanations are causal explanations for the presence and maintenance of self-reproducing systems. I contend that, insofar as the attribution of function presupposes the valuation of a function-bearing system as a causal necessity for its constituent parts, functional explanation references distinct and irreducible holistic properties. Using Kantian metaphysics to frame the discussion, this thesis aims first to explore critically the subject of functional characterisations of biological phenomena, and second, the metaphysical basis of modern science. Its chief contributions to the philosophical function debate reside in proposing novel arguments in justification of what I consider is an improved formulation of an attempted definition of biological function, in which teleological causal powers are explicitly recognised and accommodated in functional explanation. Moreover, this thesis attempts a naturalistic reconstruction of the metaphysical entailments of the real causality of a whole
- Full Text:
- Date Issued: 2020
Budgeting, forecasting and financial planning as a strategic tool in the Eastern Cape's manufacturing industry
- Authors: Abrahams, Shaheed
- Date: 2012
- Subjects: Budget process -- South Africa -- Eastern Cape , Business forecasting -- South Africa -- Eastern Cape , Business planning -- South Africa -- Eastern Cape , Manufacturing industries -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8940 , http://hdl.handle.net/10948/d1008408 , Budget process -- South Africa -- Eastern Cape , Business forecasting -- South Africa -- Eastern Cape , Business planning -- South Africa -- Eastern Cape , Manufacturing industries -- South Africa -- Eastern Cape
- Description: The primary objective of the study is to assess whether organisations are using their budgeting, forecasting and financial planning information as a strategic tool in the decision-making process. The research aims to investigate the various factors that hinder the success of the finance department in delivering a quality financial plan, budget or forecast to top management and the rest of the organisation.
- Full Text:
- Date Issued: 2012
- Authors: Abrahams, Shaheed
- Date: 2012
- Subjects: Budget process -- South Africa -- Eastern Cape , Business forecasting -- South Africa -- Eastern Cape , Business planning -- South Africa -- Eastern Cape , Manufacturing industries -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8940 , http://hdl.handle.net/10948/d1008408 , Budget process -- South Africa -- Eastern Cape , Business forecasting -- South Africa -- Eastern Cape , Business planning -- South Africa -- Eastern Cape , Manufacturing industries -- South Africa -- Eastern Cape
- Description: The primary objective of the study is to assess whether organisations are using their budgeting, forecasting and financial planning information as a strategic tool in the decision-making process. The research aims to investigate the various factors that hinder the success of the finance department in delivering a quality financial plan, budget or forecast to top management and the rest of the organisation.
- Full Text:
- Date Issued: 2012
The potential for concept cartoons to assist natural sciences teachers with developing scientific jargon for primary school learners
- Authors: Abrahams, Warda
- Date: 2019
- Subjects: Science--Study and teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10948/40219 , vital:35984
- Description: The study was undertaken to investigate whether a teaching tool Concept Cartoons may assist Intermediate Phase (IP) Natural Sciences teachers with the development and understanding of scientific jargon, when implemented in Natural Sciences investigations. As a novice Natural Sciences teacher it was important to find a teaching tool which would assist second language learners with scientific concepts, particularly focusing on science investigations. The focal aim was to search for a fun, captivating, educational resource that would cater for these learners’ barriers to science learning. This research falls within a constructivist worldview, and the research method employed was a case study. Data were collected through qualitative approach, via semi-structured interviews. A total of nine participating Intermediate Phase Natural Sciences teachers from the Port Elizabeth Northern Areas schools contributed towards the findings of this study. This study was an investigation undertaken to see whether a different teaching approach may encourage change. The findings of this study suggested that Concept Cartoons used in Natural Sciences investigations created an educational effect towards the learners understanding of science concepts. Intermediate Phase learners were introduced to Concept Cartoons to assist with their understanding of science terminology during practical investigations. The results of this investigation suggested that Concept Cartoons assisted English second-language learners with scientific jargon and served as an educative curriculum material for Intermediate Phase teachers. Furthermore Grade 4 findings suggested English home-language speakers struggled with scientific language, compared to their second-language peers who achieved greater results due to the amount of effort and determination they dedicated to translating these concepts. Further studies suggested this maybe because science terminology does not form part of their everyday vocabulary, therefore experiencing difficulty with scien1. Concept Cartoons: teachers and scientific investigations 2. Concept Cartoons: design, characters and speech bubbles 3. Concept Cartoons: enabling scientific talk 4. Concept Cartoons: scientific jargon 5. Concept Cartoons: scientific jargon and ESL learners 6. Concept Cartoons: teacher learning. This study, which aimed at introducing Concept Cartoons as an educative curriculum tool in Natural Sciences investigations, is expected to fill an important gap in literature surrounding teaching science jargon to English second-language learners.
- Full Text:
- Date Issued: 2019
- Authors: Abrahams, Warda
- Date: 2019
- Subjects: Science--Study and teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10948/40219 , vital:35984
- Description: The study was undertaken to investigate whether a teaching tool Concept Cartoons may assist Intermediate Phase (IP) Natural Sciences teachers with the development and understanding of scientific jargon, when implemented in Natural Sciences investigations. As a novice Natural Sciences teacher it was important to find a teaching tool which would assist second language learners with scientific concepts, particularly focusing on science investigations. The focal aim was to search for a fun, captivating, educational resource that would cater for these learners’ barriers to science learning. This research falls within a constructivist worldview, and the research method employed was a case study. Data were collected through qualitative approach, via semi-structured interviews. A total of nine participating Intermediate Phase Natural Sciences teachers from the Port Elizabeth Northern Areas schools contributed towards the findings of this study. This study was an investigation undertaken to see whether a different teaching approach may encourage change. The findings of this study suggested that Concept Cartoons used in Natural Sciences investigations created an educational effect towards the learners understanding of science concepts. Intermediate Phase learners were introduced to Concept Cartoons to assist with their understanding of science terminology during practical investigations. The results of this investigation suggested that Concept Cartoons assisted English second-language learners with scientific jargon and served as an educative curriculum material for Intermediate Phase teachers. Furthermore Grade 4 findings suggested English home-language speakers struggled with scientific language, compared to their second-language peers who achieved greater results due to the amount of effort and determination they dedicated to translating these concepts. Further studies suggested this maybe because science terminology does not form part of their everyday vocabulary, therefore experiencing difficulty with scien1. Concept Cartoons: teachers and scientific investigations 2. Concept Cartoons: design, characters and speech bubbles 3. Concept Cartoons: enabling scientific talk 4. Concept Cartoons: scientific jargon 5. Concept Cartoons: scientific jargon and ESL learners 6. Concept Cartoons: teacher learning. This study, which aimed at introducing Concept Cartoons as an educative curriculum tool in Natural Sciences investigations, is expected to fill an important gap in literature surrounding teaching science jargon to English second-language learners.
- Full Text:
- Date Issued: 2019
An entrepreneurial framework for new venture property development projects
- Authors: Abrey, Mark Henry Shaw
- Date: 2015
- Subjects: Real estate development -- South Africa , Entrepreneurship -- South Africa , Land subdivision -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9709 , http://hdl.handle.net/10948/d1020162
- Description: The business of real estate is one of the largest suppliers of employment, and contributes significantly to the gross domestic product of numerous countries worldwide. It is, therefore, imperative that new real estate development entrepreneurs entering the market identify key competitiveness indicators in order to survive and ensure their success within an ever-changing market. However, property development is a complex process and considered to be 'too risky' Consequently, property development entrepreneurs lack the skills and expertise to effectively manage their business enterprises and the associated risks from project inception to completion, and commissioning. The study was conducted by means of a review of the related literature and by conducting an empirical study. The empirical study was conducted using a quantitative statistical approach by distributing research questionnaires to members falling within the sample population. The primary objective of the study was to develop an entrepreneurial framework for perceived success of new venture property development projects. A descriptive survey was conducted among professionals registered with the South African Property Owners Association (SAPOA) and property development practitioners within South Africa. The salient findings suggest that the following variables positively influence the perceived success of new venture property development projects: Entrepreneurial vision; Strategic management; Stakeholders‘ interests; Professional feasibility and viability reporting; Procurement; Communication; Consumer confidence; Risk management; Governance structures; Specialist advice; The entrepreneurial framework, and The project management body of knowledge (PMBOK). Furthermore, the following variables were identified in the empirical framework affecting the perceived success of new venture property development projects: Entrepreneurial Vision; Strategic Management; Stakeholders‘ Interest; Professional Feasibility and Viability Reporting; Procurement; Communication; Consumer Confidence; Risk Management; Governance Structures; Specialist Advice, and The Project Management Body of Knowledge (PMBOK). This study contributed to the South African property development body of knowledge by addressing the challenges faced by inexperienced entrepreneurs entering the property development market. Furthermore, this study aimed to improve the framework utilised by emerging property developers.
- Full Text:
- Date Issued: 2015
- Authors: Abrey, Mark Henry Shaw
- Date: 2015
- Subjects: Real estate development -- South Africa , Entrepreneurship -- South Africa , Land subdivision -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9709 , http://hdl.handle.net/10948/d1020162
- Description: The business of real estate is one of the largest suppliers of employment, and contributes significantly to the gross domestic product of numerous countries worldwide. It is, therefore, imperative that new real estate development entrepreneurs entering the market identify key competitiveness indicators in order to survive and ensure their success within an ever-changing market. However, property development is a complex process and considered to be 'too risky' Consequently, property development entrepreneurs lack the skills and expertise to effectively manage their business enterprises and the associated risks from project inception to completion, and commissioning. The study was conducted by means of a review of the related literature and by conducting an empirical study. The empirical study was conducted using a quantitative statistical approach by distributing research questionnaires to members falling within the sample population. The primary objective of the study was to develop an entrepreneurial framework for perceived success of new venture property development projects. A descriptive survey was conducted among professionals registered with the South African Property Owners Association (SAPOA) and property development practitioners within South Africa. The salient findings suggest that the following variables positively influence the perceived success of new venture property development projects: Entrepreneurial vision; Strategic management; Stakeholders‘ interests; Professional feasibility and viability reporting; Procurement; Communication; Consumer confidence; Risk management; Governance structures; Specialist advice; The entrepreneurial framework, and The project management body of knowledge (PMBOK). Furthermore, the following variables were identified in the empirical framework affecting the perceived success of new venture property development projects: Entrepreneurial Vision; Strategic Management; Stakeholders‘ Interest; Professional Feasibility and Viability Reporting; Procurement; Communication; Consumer Confidence; Risk Management; Governance Structures; Specialist Advice, and The Project Management Body of Knowledge (PMBOK). This study contributed to the South African property development body of knowledge by addressing the challenges faced by inexperienced entrepreneurs entering the property development market. Furthermore, this study aimed to improve the framework utilised by emerging property developers.
- Full Text:
- Date Issued: 2015
Decentralization and quality assurance in the Ugandan primary education sector
- Authors: Abu-Baker, Mutaaya Sirajee
- Date: 2018
- Subjects: Schools -- Decentralization -- Uganda , Education, Primary -- Uganda , Educational change -- Uganda
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/57390 , vital:26897
- Description: The study presented in this thesis is a case study analysis of decentralization and quality assurance in a decentralized set up of the Ugandan Primary Schooling. The research looked at how the monitoring and evaluation informed the policy formulation process to regulate quality assurance in a decentralized governance of primary education. The Study was positioned in the critical realist paradigm, interpretive in orientation and used both coding and thematic techniques to understand the teachers’, SMC members’, and officers’ (at district and ministry levels) experiences and perceptions of quality assurance in a decentralized set up. Data was gathered using interviews, document analysis and observation methods. The findings indicated that the study was affected by eleven themes: Management System and Leadership, Human Resource Management, Finance Administration and Management, Parenting and Nutrition, Politics, Motivation, Social Structures and Patterns, Legislative Process and Policies, Infrastructure Development and Management, Community Involvement in Education and Curriculum and Professionalism. The monitoring and evaluation system had a framework in which it operates, though there was no quality assurance policy to guide the provision of quality education. The study finally indicated that there are more threats in a decentralized set up that put Quality in danger. Secondly, there was absence of supervision/inspection in schools as there was no evidence to prove this due to absence of reports. However, document analysis indicated visits of officers to schools. Records management was a problem to schools. Decentralization was adopted at different levels by different countries to address specific problems identified in view of service delivery. Finally, though monitoring and evaluation results informed the policy and decision makers, there was no quality assurance policy to guide the provision of quality education in institutions.
- Full Text:
- Date Issued: 2018
- Authors: Abu-Baker, Mutaaya Sirajee
- Date: 2018
- Subjects: Schools -- Decentralization -- Uganda , Education, Primary -- Uganda , Educational change -- Uganda
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/57390 , vital:26897
- Description: The study presented in this thesis is a case study analysis of decentralization and quality assurance in a decentralized set up of the Ugandan Primary Schooling. The research looked at how the monitoring and evaluation informed the policy formulation process to regulate quality assurance in a decentralized governance of primary education. The Study was positioned in the critical realist paradigm, interpretive in orientation and used both coding and thematic techniques to understand the teachers’, SMC members’, and officers’ (at district and ministry levels) experiences and perceptions of quality assurance in a decentralized set up. Data was gathered using interviews, document analysis and observation methods. The findings indicated that the study was affected by eleven themes: Management System and Leadership, Human Resource Management, Finance Administration and Management, Parenting and Nutrition, Politics, Motivation, Social Structures and Patterns, Legislative Process and Policies, Infrastructure Development and Management, Community Involvement in Education and Curriculum and Professionalism. The monitoring and evaluation system had a framework in which it operates, though there was no quality assurance policy to guide the provision of quality education. The study finally indicated that there are more threats in a decentralized set up that put Quality in danger. Secondly, there was absence of supervision/inspection in schools as there was no evidence to prove this due to absence of reports. However, document analysis indicated visits of officers to schools. Records management was a problem to schools. Decentralization was adopted at different levels by different countries to address specific problems identified in view of service delivery. Finally, though monitoring and evaluation results informed the policy and decision makers, there was no quality assurance policy to guide the provision of quality education in institutions.
- Full Text:
- Date Issued: 2018
Relative contribution of wild foods to individual and household food security in the context of increasing vulnerability due to HIV/AIDS and climate variability
- Abu-Basutu, Keitometsi Ngulube
- Authors: Abu-Basutu, Keitometsi Ngulube
- Date: 2014
- Subjects: Wild foods -- South Africa -- Eastern Cape , Food security -- South Africa , Food supply -- South Africa , AIDS (Disease) -- Social aspects -- South Africa , HIV infections -- Social aspects -- South Africa , Chronically ill -- South Africa -- Economic conditions , Chronically ill -- South Africa -- Social conditions , Food -- Social aspects -- South Africa , Food -- Economic aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4774 , http://hdl.handle.net/10962/d1010864 , Wild foods -- South Africa -- Eastern Cape , Food security -- South Africa , Food supply -- South Africa , AIDS (Disease) -- Social aspects -- South Africa , HIV infections -- Social aspects -- South Africa , Chronically ill -- South Africa -- Economic conditions , Chronically ill -- South Africa -- Social conditions , Food -- Social aspects -- South Africa , Food -- Economic aspects -- South Africa
- Description: Wild foods are an integral component of the household food basket, yet their quantified contribution to food security relative to other sources in the context of HIV/AIDS, climate change and variability remains underexplored. This study was carried out in Willowvale and Lesseyton which are rural communities in the Eastern Cape province of South Africa. Willowvale is a relatively remote, medium-rainfall coastal community, while Lesseyton is a peri-urban low rainfall inland community. Qualitative and quantitative methods were used to collect data from 78 HIV/AIDS afflicted households with 329 individuals and 87 non-afflicted households with 365 individuals in the two study sites. Households were visited quarterly over 12 months to assess food acquisition methods, dietary intake and quality, and levels of food security, and to determine strategies employed by households to cope with droughts. The wild foods investigated were wild meat, wild birds, wild fish, wild mushrooms, wild leafy vegetables and wild fruits. Diets were moderately well-balanced and limited in variety, with cereal items contributing 52 % to total calorie intake. Mid-upper arm circumference measurements showed that all respondents were adequately nourished. The bulk of the food consumed by households was purchased, with supplementation from own production, wild vegetables and wild fruits. In Willowvale, wild vegetables comprised 46 % of overall vegetable consumption for afflicted households and 32 % for non-afflicted households, while own fruit production comprised 100 % of fruit consumption. In Lesseyton, wild vegetables comprised only 6 % and 4 % of vegetable consumption for afflicted and non-afflicted households, while wild fruit comprised 63 % and 41 % for afflicted and non-afflicted households. More than 80 % of respondents from both afflicted and non-afflicted households had sufficient daily kilocalories, although the majority of afflicted households felt they were food insecure and sometimes collected wild foods as one of their multiple coping strategies. Hunting and gathering of wild foods was associated with site, household affliction status, gender, age and season. More than 80 % of respondents ate wild vegetables and said they were more drought tolerant than conventional vegetables, making them the most consumed wild food and approximately 16 % of respondents ate wild birds, making them the least consumed wild food. Approximately 14 % of respondents from afflicted households in Willowvale sold wild fish, whilst 34 % of respondents from afflicted households and 7 % from non-afflicted households sold wild fruits in Lesseyton. Strategies adopted by households to cope with droughts were different between the two study sites, and households in Willowvale used a wider range of strategies. Given the devastating effects of HIV/AIDS coupled with the drawbacks of climate change and variability on food security, wild foods represent a free and easy way for vulnerable households to obtain food.
- Full Text:
- Date Issued: 2014
- Authors: Abu-Basutu, Keitometsi Ngulube
- Date: 2014
- Subjects: Wild foods -- South Africa -- Eastern Cape , Food security -- South Africa , Food supply -- South Africa , AIDS (Disease) -- Social aspects -- South Africa , HIV infections -- Social aspects -- South Africa , Chronically ill -- South Africa -- Economic conditions , Chronically ill -- South Africa -- Social conditions , Food -- Social aspects -- South Africa , Food -- Economic aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4774 , http://hdl.handle.net/10962/d1010864 , Wild foods -- South Africa -- Eastern Cape , Food security -- South Africa , Food supply -- South Africa , AIDS (Disease) -- Social aspects -- South Africa , HIV infections -- Social aspects -- South Africa , Chronically ill -- South Africa -- Economic conditions , Chronically ill -- South Africa -- Social conditions , Food -- Social aspects -- South Africa , Food -- Economic aspects -- South Africa
- Description: Wild foods are an integral component of the household food basket, yet their quantified contribution to food security relative to other sources in the context of HIV/AIDS, climate change and variability remains underexplored. This study was carried out in Willowvale and Lesseyton which are rural communities in the Eastern Cape province of South Africa. Willowvale is a relatively remote, medium-rainfall coastal community, while Lesseyton is a peri-urban low rainfall inland community. Qualitative and quantitative methods were used to collect data from 78 HIV/AIDS afflicted households with 329 individuals and 87 non-afflicted households with 365 individuals in the two study sites. Households were visited quarterly over 12 months to assess food acquisition methods, dietary intake and quality, and levels of food security, and to determine strategies employed by households to cope with droughts. The wild foods investigated were wild meat, wild birds, wild fish, wild mushrooms, wild leafy vegetables and wild fruits. Diets were moderately well-balanced and limited in variety, with cereal items contributing 52 % to total calorie intake. Mid-upper arm circumference measurements showed that all respondents were adequately nourished. The bulk of the food consumed by households was purchased, with supplementation from own production, wild vegetables and wild fruits. In Willowvale, wild vegetables comprised 46 % of overall vegetable consumption for afflicted households and 32 % for non-afflicted households, while own fruit production comprised 100 % of fruit consumption. In Lesseyton, wild vegetables comprised only 6 % and 4 % of vegetable consumption for afflicted and non-afflicted households, while wild fruit comprised 63 % and 41 % for afflicted and non-afflicted households. More than 80 % of respondents from both afflicted and non-afflicted households had sufficient daily kilocalories, although the majority of afflicted households felt they were food insecure and sometimes collected wild foods as one of their multiple coping strategies. Hunting and gathering of wild foods was associated with site, household affliction status, gender, age and season. More than 80 % of respondents ate wild vegetables and said they were more drought tolerant than conventional vegetables, making them the most consumed wild food and approximately 16 % of respondents ate wild birds, making them the least consumed wild food. Approximately 14 % of respondents from afflicted households in Willowvale sold wild fish, whilst 34 % of respondents from afflicted households and 7 % from non-afflicted households sold wild fruits in Lesseyton. Strategies adopted by households to cope with droughts were different between the two study sites, and households in Willowvale used a wider range of strategies. Given the devastating effects of HIV/AIDS coupled with the drawbacks of climate change and variability on food security, wild foods represent a free and easy way for vulnerable households to obtain food.
- Full Text:
- Date Issued: 2014