Immunological and molecular characterization of Cryptosporidium species in HIV-Positive and HIV-Negative diarrhoea patients in the Nkonkobe Municipality of the Eastern Cape Province of South Africa: a pilot study
- Authors: Etinosa, Omoruyi Beauty
- Date: 2010
- Subjects: Protozoa, Pathogenic , Pathogenic microorganisms -- Detection , Medical microbiology , HIV-positive persons , Cryptosporidium , Diarrhea , HIV-infections
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11252 , http://hdl.handle.net/10353/392 , Protozoa, Pathogenic , Pathogenic microorganisms -- Detection , Medical microbiology , HIV-positive persons , Cryptosporidium , Diarrhea , HIV-infections
- Description: Cryptosporidiosis is an infection caused by Cryptosporidium; a protozoan parasite that infects the gastrointestinal tract. The infection is of major public health concern in both developed and developing countries. Faecal samples were collected from 160 in-patient adults, with complaint of diarrhoea, admitted at Victoria hospital in Alice, Nkonkobe Municipality. Twenty apparently healthy subjects were included as controls. All diarrhoea positive patients were interviewed to record socio-demographic information, water supply and animal contact. Initial screening was carried out by microscopy and ELISA to detect positive Cryptosporidium. Genomic DNA was extracted from microscopically positive samples and a PCR reaction was perform to amplify the (18S) SSUrRNA gene for further identification and epidemiology of Cryptosporidium. Data were analysed using Pearson‘s χ2 and Fisher‘s exact test to assess the univariate association between Cryptosporidium infection and the possible risk factors. Of the 180 subjects screened for cryptosporidial infection, Cryptosporidium antigen was detected in 122 giving an overall prevalence of 67.8 percent. In HIV-positive diarrhoea patients, prevalence increased with ages; between 31-43 (mean age 36.5 yr) and 70-82 (mean age 75.8 yr) had a higher prevalence (100 percent) of the antigen than 18-30 (mean age 23.2 yr) and 83-95 (mean age 88.8 yr) (50.0 percent) in HIV-positive diarrhoea patients (P > 0.05). In HIV-negative diarrhoea patients, prevalence was highest in the 18-30 (mean age 23.2 yr) (87.5 percent) and least (35.7 percent) in those aged 83-95 (mean age 88.8 yr) (P > 0.05). Cryptosporidium antigen was higher in females than in males. Of 115 females (mean age 46.7yr) who participated in the study, antigen was detected in 90 (78.2 percent) against 32 (71.1 percent) of 45 males (mean age 42.6yr). None of the 20 apparently healthy control subjects was found to be infected with Cryptosporidium. Cryptosporidium was detected in 27 HIV-positive and 97 HIV-negative diarrhoea patients by any one of the techniques. Antigen detection by ELISA 14 showed the highest positivity 96 (76.8 percent) in HIV- negative and 26 (74.3 percent) in HIV- positive diarrhoea patients. PCR detected eighty-nine (71.2 percent) cases in HIV-negative and 23 (65.7 percent) in HIV-positive patients with diarrhoea. Only 13 (37.1 percent) HIV-positive and 34 (27.2 percent) HIV-negative diarrhoea patients were found positive for Cryptosporidium by modified ZN. No significant difference was observed in sensitivity of antigen detection by ELISA and PCR (96.9 percent) in HIV-negative diarrhoea patients, respectively. Specificity of the staining technique was 88.9 percent in HIV-positive and 96.6 percent in HIV-negative diarrhoea patients. No significant difference was found in specificity of antigen detection by ELISA and PCR in HIV-positive and HIV-negative diarrhoea patients, respectively. Positive predictive value of ZN staining in both HIV-positive and HIV-negative diarrhoea patients (92.3 and 96.9 percent) was statistically higher than ELISA and PCR. No significant difference was observed in negative predictive value of ZN technique for detection of Cryptosporidium between HIV-positive and HIV- negative diarrhoea patients. Differences found in prevalence rates due to water source, suggest that the high infection rates of specific groups are associated with their exposure to the contaminated water supply. The results indicate that Cryptosporidium infection is highly prevalent in adult faecal specimens in the Nkonkobe Municipality, an indication of active infection that is likely to emerge as major human pathogen in this location due to socioeconomic changes which favour transmission. However, sequencing analysis is required to differentiate between Cryptosporidium genotypes in the various outbreaks
- Full Text:
- Date Issued: 2010
- Authors: Etinosa, Omoruyi Beauty
- Date: 2010
- Subjects: Protozoa, Pathogenic , Pathogenic microorganisms -- Detection , Medical microbiology , HIV-positive persons , Cryptosporidium , Diarrhea , HIV-infections
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11252 , http://hdl.handle.net/10353/392 , Protozoa, Pathogenic , Pathogenic microorganisms -- Detection , Medical microbiology , HIV-positive persons , Cryptosporidium , Diarrhea , HIV-infections
- Description: Cryptosporidiosis is an infection caused by Cryptosporidium; a protozoan parasite that infects the gastrointestinal tract. The infection is of major public health concern in both developed and developing countries. Faecal samples were collected from 160 in-patient adults, with complaint of diarrhoea, admitted at Victoria hospital in Alice, Nkonkobe Municipality. Twenty apparently healthy subjects were included as controls. All diarrhoea positive patients were interviewed to record socio-demographic information, water supply and animal contact. Initial screening was carried out by microscopy and ELISA to detect positive Cryptosporidium. Genomic DNA was extracted from microscopically positive samples and a PCR reaction was perform to amplify the (18S) SSUrRNA gene for further identification and epidemiology of Cryptosporidium. Data were analysed using Pearson‘s χ2 and Fisher‘s exact test to assess the univariate association between Cryptosporidium infection and the possible risk factors. Of the 180 subjects screened for cryptosporidial infection, Cryptosporidium antigen was detected in 122 giving an overall prevalence of 67.8 percent. In HIV-positive diarrhoea patients, prevalence increased with ages; between 31-43 (mean age 36.5 yr) and 70-82 (mean age 75.8 yr) had a higher prevalence (100 percent) of the antigen than 18-30 (mean age 23.2 yr) and 83-95 (mean age 88.8 yr) (50.0 percent) in HIV-positive diarrhoea patients (P > 0.05). In HIV-negative diarrhoea patients, prevalence was highest in the 18-30 (mean age 23.2 yr) (87.5 percent) and least (35.7 percent) in those aged 83-95 (mean age 88.8 yr) (P > 0.05). Cryptosporidium antigen was higher in females than in males. Of 115 females (mean age 46.7yr) who participated in the study, antigen was detected in 90 (78.2 percent) against 32 (71.1 percent) of 45 males (mean age 42.6yr). None of the 20 apparently healthy control subjects was found to be infected with Cryptosporidium. Cryptosporidium was detected in 27 HIV-positive and 97 HIV-negative diarrhoea patients by any one of the techniques. Antigen detection by ELISA 14 showed the highest positivity 96 (76.8 percent) in HIV- negative and 26 (74.3 percent) in HIV- positive diarrhoea patients. PCR detected eighty-nine (71.2 percent) cases in HIV-negative and 23 (65.7 percent) in HIV-positive patients with diarrhoea. Only 13 (37.1 percent) HIV-positive and 34 (27.2 percent) HIV-negative diarrhoea patients were found positive for Cryptosporidium by modified ZN. No significant difference was observed in sensitivity of antigen detection by ELISA and PCR (96.9 percent) in HIV-negative diarrhoea patients, respectively. Specificity of the staining technique was 88.9 percent in HIV-positive and 96.6 percent in HIV-negative diarrhoea patients. No significant difference was found in specificity of antigen detection by ELISA and PCR in HIV-positive and HIV-negative diarrhoea patients, respectively. Positive predictive value of ZN staining in both HIV-positive and HIV-negative diarrhoea patients (92.3 and 96.9 percent) was statistically higher than ELISA and PCR. No significant difference was observed in negative predictive value of ZN technique for detection of Cryptosporidium between HIV-positive and HIV- negative diarrhoea patients. Differences found in prevalence rates due to water source, suggest that the high infection rates of specific groups are associated with their exposure to the contaminated water supply. The results indicate that Cryptosporidium infection is highly prevalent in adult faecal specimens in the Nkonkobe Municipality, an indication of active infection that is likely to emerge as major human pathogen in this location due to socioeconomic changes which favour transmission. However, sequencing analysis is required to differentiate between Cryptosporidium genotypes in the various outbreaks
- Full Text:
- Date Issued: 2010
Impact of access to free basic electricity on households' poverty in Buffalo City Municipality in the Eastern Cape
- Authors: Mvondo, Jephthe M
- Date: 2010
- Subjects: Household surveys -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Quality of life -- South Africa -- Eastern Cape , Electric utilities -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Soc Sc (Dev)
- Identifier: vital:11419 , http://hdl.handle.net/10353/280 , Household surveys -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Quality of life -- South Africa -- Eastern Cape , Electric utilities -- South Africa -- Eastern Cape
- Description: The study was premised on the truism that men have historically served in higher echelons of organizational management structures and women are under-represented. The principal objective was to explore the constraints faced by women in accessing higher leadership and senior management positions in public, private and non-governmental organisations in Zimbabwe. This study adopted the triangulation method, that is, qualitative and quantitative approaches. These mixed research methods, were upgraded by the feminist research methodologies, thereby making a contribution in the field of research. The study found out that the constraints that mostly hinder women from accessing leadership and senior management positions in public, private and NGOs were cultural practices, which represent levels of power and control that in turn hinder reforms; and women's socialisation into feminised roles. The study also found out that in most organisations, most females work under male leadership, and this traditional organisational culture, needs to be deconstructed and reversed in order to achieve gender equality. The study recommended for a human centric and integrated organizational management strategy for public, private and NGOs in Zimbabwe. The adoption of a human centric and integrated management approach should aim at gender equity and reduce women's under-representation. A human centred organizational culture has to be practiced, that would create organisational ethos that guide organizational management. An integrated organizational management approach should integrate all systems and processes into one complete framework, enabling people to work as a single unit, unified by organizational goals, shared vision and common values. The system should depend on a balanced mix of the masculine and feminine attributes. The approach should put its weight towards adoption of measures to attract, advance and empower women so as to benefit from their qualifications, experience and talent in a highly competitive environment.
- Full Text:
- Date Issued: 2010
- Authors: Mvondo, Jephthe M
- Date: 2010
- Subjects: Household surveys -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Quality of life -- South Africa -- Eastern Cape , Electric utilities -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Soc Sc (Dev)
- Identifier: vital:11419 , http://hdl.handle.net/10353/280 , Household surveys -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Quality of life -- South Africa -- Eastern Cape , Electric utilities -- South Africa -- Eastern Cape
- Description: The study was premised on the truism that men have historically served in higher echelons of organizational management structures and women are under-represented. The principal objective was to explore the constraints faced by women in accessing higher leadership and senior management positions in public, private and non-governmental organisations in Zimbabwe. This study adopted the triangulation method, that is, qualitative and quantitative approaches. These mixed research methods, were upgraded by the feminist research methodologies, thereby making a contribution in the field of research. The study found out that the constraints that mostly hinder women from accessing leadership and senior management positions in public, private and NGOs were cultural practices, which represent levels of power and control that in turn hinder reforms; and women's socialisation into feminised roles. The study also found out that in most organisations, most females work under male leadership, and this traditional organisational culture, needs to be deconstructed and reversed in order to achieve gender equality. The study recommended for a human centric and integrated organizational management strategy for public, private and NGOs in Zimbabwe. The adoption of a human centric and integrated management approach should aim at gender equity and reduce women's under-representation. A human centred organizational culture has to be practiced, that would create organisational ethos that guide organizational management. An integrated organizational management approach should integrate all systems and processes into one complete framework, enabling people to work as a single unit, unified by organizational goals, shared vision and common values. The system should depend on a balanced mix of the masculine and feminine attributes. The approach should put its weight towards adoption of measures to attract, advance and empower women so as to benefit from their qualifications, experience and talent in a highly competitive environment.
- Full Text:
- Date Issued: 2010
Impact of in-field rainwater harvesting technology on household food security: a case of Guquka and Khayalethu villages in Central Eastern Cape Province
- Hlanganise, Yoliswa Happiness
- Authors: Hlanganise, Yoliswa Happiness
- Date: 2010
- Subjects: Water consumption -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11179 , http://hdl.handle.net/10353/352 , Water consumption -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Description: The aim of this investigation was to assess the impact of the In-Field Rainwater Harvesting technology on household food security in the study area. The study was conducted in Nkonkobe Local Municipality of the Amathole District Municipality in central Eastern Cape Province. The areas under investigation are Guquka and Khayaletu villages of the Thyume Valley, which is located about 30 kilometres north of Alice. The method used to assess the impact of the IRWH on household food security was a pair wise comparison method. During September 2009, there were 60 (34 in Guquka and 26 in Khayaletu) households who adopted the technology in home gardens. In order to get a clear picture of the impact of the technology on food security, a decision was taken to assess both the project members and non-project members, hence the pairwise comparison method. The non-project members (also 60 households) were selected randomly from those who were interviewed during the situation analysis in 2004. Five indicators were used to assess household food security. These were household income, expenditure on food, diet diversity, energy-protein intakes, and micro-nutrient intakes (Vitamin A, C and Iron). The income and expenditure data were collected from the 120 households. However, the detailed food data were collected from selected cases from both groups at different times (seasons) of the year. A case study approach was employed in data collection. A total of 12 cases (six households per village) were selected for this investigation. These were selected mainly according to the degree of poverty. The total of six households from each village comprised three project members and three non-members i.e. one from each poverty class (non- poor, poor and ultra-poor) in both categories. The data on the kinds of food products consumed by households was gathered using the food account method (FAM). The food consumed was then analysed for nutrient adequacy. The main findings of this investigation show the IRWH technology to have a positive impact on food security and nutrition of the project members. The technology made significant contributions to the amount of energy and vitamins A and C consumed by households especially during wet seasons. Substantial contributions of garden produce were noted among the project members. However, these contributions were not enough to ensure household food security. The results indicate that there are nutritional problems in the study area. Firstly, there is protein- v energy malnutrition mainly affecting the poor and the ultra-poor households. Secondly, there is hidden hunger affecting all poverty categories, even the non-poor households. This is mainly demonstrated by poor diet quality i.e. diet that lacks essential nutrients identified
- Full Text:
- Date Issued: 2010
- Authors: Hlanganise, Yoliswa Happiness
- Date: 2010
- Subjects: Water consumption -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11179 , http://hdl.handle.net/10353/352 , Water consumption -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Description: The aim of this investigation was to assess the impact of the In-Field Rainwater Harvesting technology on household food security in the study area. The study was conducted in Nkonkobe Local Municipality of the Amathole District Municipality in central Eastern Cape Province. The areas under investigation are Guquka and Khayaletu villages of the Thyume Valley, which is located about 30 kilometres north of Alice. The method used to assess the impact of the IRWH on household food security was a pair wise comparison method. During September 2009, there were 60 (34 in Guquka and 26 in Khayaletu) households who adopted the technology in home gardens. In order to get a clear picture of the impact of the technology on food security, a decision was taken to assess both the project members and non-project members, hence the pairwise comparison method. The non-project members (also 60 households) were selected randomly from those who were interviewed during the situation analysis in 2004. Five indicators were used to assess household food security. These were household income, expenditure on food, diet diversity, energy-protein intakes, and micro-nutrient intakes (Vitamin A, C and Iron). The income and expenditure data were collected from the 120 households. However, the detailed food data were collected from selected cases from both groups at different times (seasons) of the year. A case study approach was employed in data collection. A total of 12 cases (six households per village) were selected for this investigation. These were selected mainly according to the degree of poverty. The total of six households from each village comprised three project members and three non-members i.e. one from each poverty class (non- poor, poor and ultra-poor) in both categories. The data on the kinds of food products consumed by households was gathered using the food account method (FAM). The food consumed was then analysed for nutrient adequacy. The main findings of this investigation show the IRWH technology to have a positive impact on food security and nutrition of the project members. The technology made significant contributions to the amount of energy and vitamins A and C consumed by households especially during wet seasons. Substantial contributions of garden produce were noted among the project members. However, these contributions were not enough to ensure household food security. The results indicate that there are nutritional problems in the study area. Firstly, there is protein- v energy malnutrition mainly affecting the poor and the ultra-poor households. Secondly, there is hidden hunger affecting all poverty categories, even the non-poor households. This is mainly demonstrated by poor diet quality i.e. diet that lacks essential nutrients identified
- Full Text:
- Date Issued: 2010
Improving Productivity of Maize-based Smallholder Irrigated Cropping Systems: A Case Study of Zanyokwe Irrigation Scheme, Eastern Cape, South Africa
- Authors: Fanadzo, Morris
- Date: 2010
- Subjects: Farms, Small -- South Africa -- Eastern Cape Crop yields -- South Africa -- Eastern Cape Agricultural productivity -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/11009 , vital:36450
- Description: Smallholder irrigation schemes (SIS) in South Africa have performed poorly and failed to achieve the development objectives of sustaining rural livelihoods by increasing crop production and income. Limited knowledge of crop production among farmers is one constraint to improved crop productivity and, yet little research has been carried out to relate agronomic practices to productivity. This study was aimed at identifying strategies to improve the productivity of maize-based smallholder irrigated cropping systems in South Africa, using Zanyokwe irrigation scheme (ZIS) in the Eastern Cape Province as a case study. The research design was emergent, developed progressively as influenced by the progressive analyses that were made. The research work involved two main phases: exploratory studies and refinement on-farm experiments for testing technologies as informed by the exploratory studies. Exploratory studies were aimed at describing farmer crop production practices in major crop enterprises and identifying and prioritizing major agronomic yield constraints. Findings indicated that the overall performance of the cropping systems was poor as evidenced by low overall yields of < 25% of the potential in maize and butternut. Poor management of weeds, soil fertility, plant populations and water, late planting and poor cultivar choice were the most important yield constraints. The average cropping intensity achieved by farmers was only 48%. New hybrids yielded 50 - 65% higher grain than the cultivars commonly grown by farmers. However, farmers favoured their traditional cultivars, as they preferred green maize production as opposed to dry grains. As a result of these findings, focused research was designed on options for iii improving green maize production, soil fertility, crop stand and weed management in crop production. On-farm trials were, therefore, designed to (1) compare the response to nitrogen (N) rate of direct seeded and transplanted maize; (2) evaluate comparative performance of direct seeded and transplanted green maize under farmer management, and to work out the economics of transplanting; (3) investigate the effects of row spacing and atrazine dosage on weed dynamics maize yield; (4) determine the effects of inter-row spacing and plant population on weed dynamics and maize yield; and (5) investigate the effects of pre-plant weed control, N rate and plant population on weed dynamics and butternut yield. Maize transplanting improved crop stand, had earlier maturity and yielded higher at lower N rates compared to direct seeding for both green and grain maize. Total costs that varied were higher by R3 565 ha-1 for transplanted maize compared to direct-seeded maize, but the net benefits from transplanting were also much higher by R8 773 ha-1. Farmers favoured transplanting, citing bigger cobs, early maturity and the absence of seedling damage by birds, when maize was transplanted. However, a follow-up survey conducted during the subsequent year indicated that five of the six farmers abandoned transplanting, citing shortage of labour and high cost of commercially produced seedlings. It was concluded that transplanting is unlikely to be adopted unless the labour intensiveness of manual transplanting can be solved. Increasing atrazine dosage from a third of the label recommended dosage (LRD) and reducing row spacing from 90 to 45 cm resulted in an increase in weed mortality. A 100% kill of annual broadleaf weeds was possible while iv perennial grasses and the annual broadleaf weed, Oxalis latifolia, could not be controlled even at the LRD. However, improved weed mortality with increase in atrazine dosage and/or narrow rows did not translate into improved maize productivity. In butternut, pre-plant weed control resulted in a six-fold decrease in weed biomass and a 100% increase in fruit yield. These findings demonstrated the possibility of incorporation of reduced herbicide dosages and narrow rows to achieve adequate weed control and optimise on maize yields in smallholder farming systems. The results also suggested that pre-plant weed control is one of the pre-requisite to successful butternut production in SIS in South Africa. Increasing maize population from 40 000 to 60 000 plants ha-1 resulted in a 30% grain yield increase, but decreased length of cobs. Row spacing had no effect on maize yield at 40 000 plants ha-1, but at 60 000 plants ha-1 45 cm rows resulted in 11% higher grain yield (12 547 kg ha-1) than 90 cm rows (11 288 kg ha-1). Butternut yield increased significantly (p < 0.01) with increase in plant population and N rate. The optimum butternut population and N rate were estimated at 25 000 plants ha-1 and 120 kg N ha-1, respectively. Pre-plant weed control in butternut resulted in a six-fold decrease in weed biomass. Increasing butternut planting density from 10 000 to 30 000 plants ha-1 decreased weed biomass by 47%. No marketable fruits were obtained when planting was done without prior weed control. This result suggest that application of non-selective herbicide before planting is one technique that can be used by farmers as part of integrated weed management to give the crop a competitive advantage in the early growth stages before the plants start to produce vines. Yield increased significantly (p < 0.01) with increase in plant density and N rate. The optimum plant density and N rate were estimated at 25 000 plants ha-1 and 120 kg N ha-1, respectively. These findings emphasise the need to take into consideration production practices by farmers as a basis to build up skills in the management of crop enterprises and the farm as a viable business in any efforts to improve on the performance of SIS in South Africa. Future research should concentrate on labour-saving sustainable production technologies for SIS in South Africa.
- Full Text:
- Date Issued: 2010
- Authors: Fanadzo, Morris
- Date: 2010
- Subjects: Farms, Small -- South Africa -- Eastern Cape Crop yields -- South Africa -- Eastern Cape Agricultural productivity -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/11009 , vital:36450
- Description: Smallholder irrigation schemes (SIS) in South Africa have performed poorly and failed to achieve the development objectives of sustaining rural livelihoods by increasing crop production and income. Limited knowledge of crop production among farmers is one constraint to improved crop productivity and, yet little research has been carried out to relate agronomic practices to productivity. This study was aimed at identifying strategies to improve the productivity of maize-based smallholder irrigated cropping systems in South Africa, using Zanyokwe irrigation scheme (ZIS) in the Eastern Cape Province as a case study. The research design was emergent, developed progressively as influenced by the progressive analyses that were made. The research work involved two main phases: exploratory studies and refinement on-farm experiments for testing technologies as informed by the exploratory studies. Exploratory studies were aimed at describing farmer crop production practices in major crop enterprises and identifying and prioritizing major agronomic yield constraints. Findings indicated that the overall performance of the cropping systems was poor as evidenced by low overall yields of < 25% of the potential in maize and butternut. Poor management of weeds, soil fertility, plant populations and water, late planting and poor cultivar choice were the most important yield constraints. The average cropping intensity achieved by farmers was only 48%. New hybrids yielded 50 - 65% higher grain than the cultivars commonly grown by farmers. However, farmers favoured their traditional cultivars, as they preferred green maize production as opposed to dry grains. As a result of these findings, focused research was designed on options for iii improving green maize production, soil fertility, crop stand and weed management in crop production. On-farm trials were, therefore, designed to (1) compare the response to nitrogen (N) rate of direct seeded and transplanted maize; (2) evaluate comparative performance of direct seeded and transplanted green maize under farmer management, and to work out the economics of transplanting; (3) investigate the effects of row spacing and atrazine dosage on weed dynamics maize yield; (4) determine the effects of inter-row spacing and plant population on weed dynamics and maize yield; and (5) investigate the effects of pre-plant weed control, N rate and plant population on weed dynamics and butternut yield. Maize transplanting improved crop stand, had earlier maturity and yielded higher at lower N rates compared to direct seeding for both green and grain maize. Total costs that varied were higher by R3 565 ha-1 for transplanted maize compared to direct-seeded maize, but the net benefits from transplanting were also much higher by R8 773 ha-1. Farmers favoured transplanting, citing bigger cobs, early maturity and the absence of seedling damage by birds, when maize was transplanted. However, a follow-up survey conducted during the subsequent year indicated that five of the six farmers abandoned transplanting, citing shortage of labour and high cost of commercially produced seedlings. It was concluded that transplanting is unlikely to be adopted unless the labour intensiveness of manual transplanting can be solved. Increasing atrazine dosage from a third of the label recommended dosage (LRD) and reducing row spacing from 90 to 45 cm resulted in an increase in weed mortality. A 100% kill of annual broadleaf weeds was possible while iv perennial grasses and the annual broadleaf weed, Oxalis latifolia, could not be controlled even at the LRD. However, improved weed mortality with increase in atrazine dosage and/or narrow rows did not translate into improved maize productivity. In butternut, pre-plant weed control resulted in a six-fold decrease in weed biomass and a 100% increase in fruit yield. These findings demonstrated the possibility of incorporation of reduced herbicide dosages and narrow rows to achieve adequate weed control and optimise on maize yields in smallholder farming systems. The results also suggested that pre-plant weed control is one of the pre-requisite to successful butternut production in SIS in South Africa. Increasing maize population from 40 000 to 60 000 plants ha-1 resulted in a 30% grain yield increase, but decreased length of cobs. Row spacing had no effect on maize yield at 40 000 plants ha-1, but at 60 000 plants ha-1 45 cm rows resulted in 11% higher grain yield (12 547 kg ha-1) than 90 cm rows (11 288 kg ha-1). Butternut yield increased significantly (p < 0.01) with increase in plant population and N rate. The optimum butternut population and N rate were estimated at 25 000 plants ha-1 and 120 kg N ha-1, respectively. Pre-plant weed control in butternut resulted in a six-fold decrease in weed biomass. Increasing butternut planting density from 10 000 to 30 000 plants ha-1 decreased weed biomass by 47%. No marketable fruits were obtained when planting was done without prior weed control. This result suggest that application of non-selective herbicide before planting is one technique that can be used by farmers as part of integrated weed management to give the crop a competitive advantage in the early growth stages before the plants start to produce vines. Yield increased significantly (p < 0.01) with increase in plant density and N rate. The optimum plant density and N rate were estimated at 25 000 plants ha-1 and 120 kg N ha-1, respectively. These findings emphasise the need to take into consideration production practices by farmers as a basis to build up skills in the management of crop enterprises and the farm as a viable business in any efforts to improve on the performance of SIS in South Africa. Future research should concentrate on labour-saving sustainable production technologies for SIS in South Africa.
- Full Text:
- Date Issued: 2010
Improving sanitization and fertiliser value of dairy manure and waste paper mixtures enriched with rock phosphate through combined thermophilic composting and vermicomposting
- Authors: Mupondi, Lushian Tapiwa
- Date: 2010
- Subjects: Compost , Vermicomposting , Manures , Biodegradation , Waste paper -- South Africa -- Eastern Cape , Thermophilic bacteria , Fertilizers
- Language: English
- Type: Thesis , Doctoral , PhD (Soil Science)
- Identifier: vital:11961 , http://hdl.handle.net/10353/411 , Compost , Vermicomposting , Manures , Biodegradation , Waste paper -- South Africa -- Eastern Cape , Thermophilic bacteria , Fertilizers
- Description: Thermophilic composting (TC) and vermicomposting (V) are the two most common methods used for biological stabilization of solid organic wastes. Both have their advantages and disadvantages but the proposed method of combining composting and vermicomposting (CV) borrows pertinent attributes from each of the two methods and combines them to enhance overall process and product qualities. Dairy manure and waste paper are two wastes produced in large quantities at the University of Fort Hare. The study was carried out to address the following specific objectives, to determine (i) the effectiveness of combined thermophilic composting and vermicomposting on the biodegradation and sanitization of mixtures of dairy manure and paper waste, (ii) an optimum precomposting period for dairy manure paper waste mixtures that results in vermicomposts of good nutritional quality and whose use will not jeopardize human health, (iii) the effectiveness of phosphate rock (PR) in increasing available P and degradation and nutrient content of dairy manure-paper vermicomposts, (iv) the physicochemical properties of vermicompost substituted pine bark compost and performance of resultant growing medium on plant growth and nutrient uptake. Results of this study revealed that wastes with a C: N ratio of 30 were more suitable for both V and CV as their composts were more stabilized and with higher nutrient contents than composts made from wastes with a C: N ratio of 45. Both V and CV were effective methods for the biodegradation of dairy manure and paper waste mixtures with C: N ratio of 30 but the latter was more effective in the biodegradation of waste mixtures with a C: N ratio of 45. The combinination of composting and vermicomposting eliminated the indicator pathogen E. coli 0157 from the final composts whereas V only managed to reduce the pathogen population. iv A follow up study was done to determine the effects of precomposting on pathogen numbers so as to come up with a suitable precomposting period to use when combine composting dairy manure-waste paper mixtures. Results of this study showed that over 95% of fecal coliforms, E. coli and of E. coli 0157 were eliminated from the wastes within one week of precomposting and total elimination of these and protozoan (oo)cysts achieved after 3 weeks of precomposting. The vermicomposts pathogen content was related to the waste’s precomposting period. Final vermicomposts pathogen content was reduced and varied according to precomposting period. Vermicomposts from wastes precomposted for over two weeks were less stabilized, less humified and had less nutrient contents compared to vermicomposts from wastes that were precomposted for one week or less. The findings suggest that a precomposting period of one week is ideal for the effective vermicomposting of dairy manure-waste paper mixtures. Results of the P enrichment study indicated an increase in the inorganic phosphate and a reduction in the organic phosphate fractions of dairy manure-waste paper vermicompost that were enriched with PR. This implied an increase in mineralization of organic matter and or solubilization of PR with vermicomposting time. Applying PR to dairy manure-waste paper mixtures also enhanced degradation and had increased N and P contents of dairy manure-waste paper vermicomposts. Earthworms accumulated heavy metals in their bodies and reduced heavy metal contents of vermicomposts. A study to determine the physicochemical properties of vermicompost substituted pine bark compost and performance of resultant growing medium on plant growth and nutrient uptake was done. Results obtained revealed that increasing proportions of dairy manure vermicomposts in pine bark compost improved tomato plant height, stem girth, shoot and root dry weights. v Tomatoes grew best in the 40 to 60% CV substituted pine bark and application of Horticote (7:2:1 (22)) fertilizer significantly increased plant growth in all media. Progressive substitution pine bark with dairy manure vermicomposts resulted in a decrease in the percentage total porosity, percentage air space whilst bulk density, water holding capacity, particle density, pH, electrical conductivity and N and P levels increased. Precomposting wastes not only reduced and or eliminated pathogens but also improved the stabilisation and nutrient content of dairy manure waste paper mixtures. The application of PR to dairy manure waste paper mixtures improved the chemical and physical properties of vermicomposts. Earthworms bio-accumulated the heavy metals Cd, Cr, Cu, Pb and Zn whilst the contents of these in the vermicomposts declined. It is, therefore, recommended that dairy manure waste paper mixtures be precomposted for one week for sanitization followed by PR application and vermicomposting for stabilization and improved nutrients contents of resultant vermicomposts. Substitution of pine bark compost with 40 to 60 % PR-enriched vermicompost produced a growing medium with superior physical and chemical properties which supported good seedling growth. However, for optimum seedling growth, supplementation with mineral fertilizer was found to be necessary.
- Full Text:
- Date Issued: 2010
- Authors: Mupondi, Lushian Tapiwa
- Date: 2010
- Subjects: Compost , Vermicomposting , Manures , Biodegradation , Waste paper -- South Africa -- Eastern Cape , Thermophilic bacteria , Fertilizers
- Language: English
- Type: Thesis , Doctoral , PhD (Soil Science)
- Identifier: vital:11961 , http://hdl.handle.net/10353/411 , Compost , Vermicomposting , Manures , Biodegradation , Waste paper -- South Africa -- Eastern Cape , Thermophilic bacteria , Fertilizers
- Description: Thermophilic composting (TC) and vermicomposting (V) are the two most common methods used for biological stabilization of solid organic wastes. Both have their advantages and disadvantages but the proposed method of combining composting and vermicomposting (CV) borrows pertinent attributes from each of the two methods and combines them to enhance overall process and product qualities. Dairy manure and waste paper are two wastes produced in large quantities at the University of Fort Hare. The study was carried out to address the following specific objectives, to determine (i) the effectiveness of combined thermophilic composting and vermicomposting on the biodegradation and sanitization of mixtures of dairy manure and paper waste, (ii) an optimum precomposting period for dairy manure paper waste mixtures that results in vermicomposts of good nutritional quality and whose use will not jeopardize human health, (iii) the effectiveness of phosphate rock (PR) in increasing available P and degradation and nutrient content of dairy manure-paper vermicomposts, (iv) the physicochemical properties of vermicompost substituted pine bark compost and performance of resultant growing medium on plant growth and nutrient uptake. Results of this study revealed that wastes with a C: N ratio of 30 were more suitable for both V and CV as their composts were more stabilized and with higher nutrient contents than composts made from wastes with a C: N ratio of 45. Both V and CV were effective methods for the biodegradation of dairy manure and paper waste mixtures with C: N ratio of 30 but the latter was more effective in the biodegradation of waste mixtures with a C: N ratio of 45. The combinination of composting and vermicomposting eliminated the indicator pathogen E. coli 0157 from the final composts whereas V only managed to reduce the pathogen population. iv A follow up study was done to determine the effects of precomposting on pathogen numbers so as to come up with a suitable precomposting period to use when combine composting dairy manure-waste paper mixtures. Results of this study showed that over 95% of fecal coliforms, E. coli and of E. coli 0157 were eliminated from the wastes within one week of precomposting and total elimination of these and protozoan (oo)cysts achieved after 3 weeks of precomposting. The vermicomposts pathogen content was related to the waste’s precomposting period. Final vermicomposts pathogen content was reduced and varied according to precomposting period. Vermicomposts from wastes precomposted for over two weeks were less stabilized, less humified and had less nutrient contents compared to vermicomposts from wastes that were precomposted for one week or less. The findings suggest that a precomposting period of one week is ideal for the effective vermicomposting of dairy manure-waste paper mixtures. Results of the P enrichment study indicated an increase in the inorganic phosphate and a reduction in the organic phosphate fractions of dairy manure-waste paper vermicompost that were enriched with PR. This implied an increase in mineralization of organic matter and or solubilization of PR with vermicomposting time. Applying PR to dairy manure-waste paper mixtures also enhanced degradation and had increased N and P contents of dairy manure-waste paper vermicomposts. Earthworms accumulated heavy metals in their bodies and reduced heavy metal contents of vermicomposts. A study to determine the physicochemical properties of vermicompost substituted pine bark compost and performance of resultant growing medium on plant growth and nutrient uptake was done. Results obtained revealed that increasing proportions of dairy manure vermicomposts in pine bark compost improved tomato plant height, stem girth, shoot and root dry weights. v Tomatoes grew best in the 40 to 60% CV substituted pine bark and application of Horticote (7:2:1 (22)) fertilizer significantly increased plant growth in all media. Progressive substitution pine bark with dairy manure vermicomposts resulted in a decrease in the percentage total porosity, percentage air space whilst bulk density, water holding capacity, particle density, pH, electrical conductivity and N and P levels increased. Precomposting wastes not only reduced and or eliminated pathogens but also improved the stabilisation and nutrient content of dairy manure waste paper mixtures. The application of PR to dairy manure waste paper mixtures improved the chemical and physical properties of vermicomposts. Earthworms bio-accumulated the heavy metals Cd, Cr, Cu, Pb and Zn whilst the contents of these in the vermicomposts declined. It is, therefore, recommended that dairy manure waste paper mixtures be precomposted for one week for sanitization followed by PR application and vermicomposting for stabilization and improved nutrients contents of resultant vermicomposts. Substitution of pine bark compost with 40 to 60 % PR-enriched vermicompost produced a growing medium with superior physical and chemical properties which supported good seedling growth. However, for optimum seedling growth, supplementation with mineral fertilizer was found to be necessary.
- Full Text:
- Date Issued: 2010
In vitro bioactivity of crude extracts of Lippia javanica on clinical isolates of Helicobacter pylori: preliminary phytochemical screening
- Authors: Nkomo, Lindelwa Precious
- Date: 2010
- Subjects: Extracts , Helicobacter pylori , Antibiotics , Drug resistance in microorganisms , Materia medica, Vegetable
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11257 , http://hdl.handle.net/10353/508 , Extracts , Helicobacter pylori , Antibiotics , Drug resistance in microorganisms , Materia medica, Vegetable
- Description: Helicobacter pylori classified as a class 1 carcinogen is a common human pathogen implicated in certain gastrointestinal diseases. Helicobacter pylori infection is acquired mainly in childhood, especially in developing countries. H. pylori infection causes peptic ulcer, duodenitis, gastritis and cancer. The growing resistance of H. pylori to antibiotics used in its treatment as well as other innate limitations of the triple therapy has necessitated a search for alternative treatment from natural sources which could be readily available, less cost effective. The antimicrobial activity of solvents (acetone, ethanol, methanol, chloroform and water) crude extracts of Lippia javanica were investigated against 31 H. pylori strains by the agar well diffusion technique. The minimum inhibitory concentration (MIC) was determined by spectrophotometric analysis at 620 nm using the broth micro dilution method and the rate of kill by broth dilution method. Phytochemical analysis was also performed. H. pylori standard strain NCTC 11638 was included as a positive control. Metronidazole and amoxicillin were used as positive control antibiotics. The ANOVA test was used to analyze the results using SPSS version 17.0. The strains were inhibited by all the extracts with inhibition zones of diameter ranging from 0-36 mm and 0-35 mm for the control antibiotic, clarithromycin. The MIC90 ranged from 0.039- 0.625 mg/mL for acetone; 0.039-1.25mg/mL for methanol, 0.00195-0.313 mg/mL for ethanol; 0.01975-2.5 mg/mL for metronidazole and 0.0048-2.5 mg/mL for amoxicillin. Acetone extract completely inhibited strain PE369C at MIC (0.1 mg/mL) and 2× MIC (0.2 mg/mL) in 18h and at ½× MIC (0.05 mg/mL) in 36h. Strain PE466C was completely inhibited at 4× MIC in 72h. Phytochemical analysis revealed the presence of flavonoids, saponins, tannins, steroids and alkaloids. The results indicate that the extracts of the leaves of L. javanica may contain compounds with anti-H. pylori activity and merits further study to identify the compounds.
- Full Text:
- Date Issued: 2010
- Authors: Nkomo, Lindelwa Precious
- Date: 2010
- Subjects: Extracts , Helicobacter pylori , Antibiotics , Drug resistance in microorganisms , Materia medica, Vegetable
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11257 , http://hdl.handle.net/10353/508 , Extracts , Helicobacter pylori , Antibiotics , Drug resistance in microorganisms , Materia medica, Vegetable
- Description: Helicobacter pylori classified as a class 1 carcinogen is a common human pathogen implicated in certain gastrointestinal diseases. Helicobacter pylori infection is acquired mainly in childhood, especially in developing countries. H. pylori infection causes peptic ulcer, duodenitis, gastritis and cancer. The growing resistance of H. pylori to antibiotics used in its treatment as well as other innate limitations of the triple therapy has necessitated a search for alternative treatment from natural sources which could be readily available, less cost effective. The antimicrobial activity of solvents (acetone, ethanol, methanol, chloroform and water) crude extracts of Lippia javanica were investigated against 31 H. pylori strains by the agar well diffusion technique. The minimum inhibitory concentration (MIC) was determined by spectrophotometric analysis at 620 nm using the broth micro dilution method and the rate of kill by broth dilution method. Phytochemical analysis was also performed. H. pylori standard strain NCTC 11638 was included as a positive control. Metronidazole and amoxicillin were used as positive control antibiotics. The ANOVA test was used to analyze the results using SPSS version 17.0. The strains were inhibited by all the extracts with inhibition zones of diameter ranging from 0-36 mm and 0-35 mm for the control antibiotic, clarithromycin. The MIC90 ranged from 0.039- 0.625 mg/mL for acetone; 0.039-1.25mg/mL for methanol, 0.00195-0.313 mg/mL for ethanol; 0.01975-2.5 mg/mL for metronidazole and 0.0048-2.5 mg/mL for amoxicillin. Acetone extract completely inhibited strain PE369C at MIC (0.1 mg/mL) and 2× MIC (0.2 mg/mL) in 18h and at ½× MIC (0.05 mg/mL) in 36h. Strain PE466C was completely inhibited at 4× MIC in 72h. Phytochemical analysis revealed the presence of flavonoids, saponins, tannins, steroids and alkaloids. The results indicate that the extracts of the leaves of L. javanica may contain compounds with anti-H. pylori activity and merits further study to identify the compounds.
- Full Text:
- Date Issued: 2010
Influence of mite predation on the efficacy of the gall midge Dasineura sp. as a biocontrol agent of Australian myrtle Leptospermum laevigatum (Myrtaceae) in South Africa
- Mdlangu, Thabisa Lynette Honey
- Authors: Mdlangu, Thabisa Lynette Honey
- Date: 2010
- Subjects: Dasyneura leguminicola , Myrtaceae -- South Africa , Mites as biological pest control agents , Pests -- Biological control , Biological pest control agents , Predation (Biology)
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11789 , http://hdl.handle.net/10353/272 , Dasyneura leguminicola , Myrtaceae -- South Africa , Mites as biological pest control agents , Pests -- Biological control , Biological pest control agents , Predation (Biology)
- Description: Dasineura sp. is a gall forming midge that was introduced into South Africa for the biocontrol of the Australian myrtle, Leptospermum laevigatum. It causes galls on both the vegetative and reproductive buds of the plant. Although Dasineura sp. was initially regarded as a potentially successful agent, galling up to 99 percent of the buds of the host plant, it has been preyed on by native opportunistic mites, which caused a decline in the performance of the midge as a biocontrol agent of L. laevigatum. This raised a concern about whether this fly will be able to perform effectively in the presence of its new natural enemies. Therefore, the objectives of this study were to: 1) ascertain whether mite abundance has seasonal variations; 2) determine if plant density and plant size have an effect on midge predation by the mites; and 3) determine if midge predation varies in different locations. The study was conducted at three sites in the Hermanus area, Western Cape Province. Every three weeks for thirteen months, galls were collected and dissected so as to count and record the numbers of midge larvae, pupae, adults and mites that were found. Data collected showed that predation varied with season, and the mites were scarce during the flowering season. Predation also varied among the study sites and plant density had an effect on midge predation. Midges in smaller plants (saplings) were more vulnerable to predation than those in the bigger plants (plants from isolates and thickets). It was concluded that although mites have an effect on midge populations, they do not prevent their establishment on the plant. Therefore, a survey should be done in two to three years time to check if the midges are still persisting on the plant, vi and recommendations are that a new agent should be released to supplement the midges.
- Full Text:
- Date Issued: 2010
- Authors: Mdlangu, Thabisa Lynette Honey
- Date: 2010
- Subjects: Dasyneura leguminicola , Myrtaceae -- South Africa , Mites as biological pest control agents , Pests -- Biological control , Biological pest control agents , Predation (Biology)
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11789 , http://hdl.handle.net/10353/272 , Dasyneura leguminicola , Myrtaceae -- South Africa , Mites as biological pest control agents , Pests -- Biological control , Biological pest control agents , Predation (Biology)
- Description: Dasineura sp. is a gall forming midge that was introduced into South Africa for the biocontrol of the Australian myrtle, Leptospermum laevigatum. It causes galls on both the vegetative and reproductive buds of the plant. Although Dasineura sp. was initially regarded as a potentially successful agent, galling up to 99 percent of the buds of the host plant, it has been preyed on by native opportunistic mites, which caused a decline in the performance of the midge as a biocontrol agent of L. laevigatum. This raised a concern about whether this fly will be able to perform effectively in the presence of its new natural enemies. Therefore, the objectives of this study were to: 1) ascertain whether mite abundance has seasonal variations; 2) determine if plant density and plant size have an effect on midge predation by the mites; and 3) determine if midge predation varies in different locations. The study was conducted at three sites in the Hermanus area, Western Cape Province. Every three weeks for thirteen months, galls were collected and dissected so as to count and record the numbers of midge larvae, pupae, adults and mites that were found. Data collected showed that predation varied with season, and the mites were scarce during the flowering season. Predation also varied among the study sites and plant density had an effect on midge predation. Midges in smaller plants (saplings) were more vulnerable to predation than those in the bigger plants (plants from isolates and thickets). It was concluded that although mites have an effect on midge populations, they do not prevent their establishment on the plant. Therefore, a survey should be done in two to three years time to check if the midges are still persisting on the plant, vi and recommendations are that a new agent should be released to supplement the midges.
- Full Text:
- Date Issued: 2010
Investigation and development of an e judiciary service for a citizen oriented judiciary system for rural communities
- Authors: Scott, Mfundo Shakes
- Date: 2010
- Subjects: Digital divide -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , User interfaces (Computer systems)
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11390 , http://hdl.handle.net/10353/275 , Digital divide -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , User interfaces (Computer systems)
- Description: One of the factors that contribute towards slow rural development is the presence of the digital divide. An area where the digital divide is still prevalent is the administration of justice within traditional contexts. One of the areas affected by this problem is the Dwesa rural community, situated on the Wild Coast of the former homeland of Transkei, in the Eastern Cape Province of South Africa. To address this problem for the Dwesa community, a research project on developing and implementing an e-Judiciary service was undertaken. The primary objective of this project was to develop a web application to support traditional justice administration in the Dwesa community. Due to the lack of a proper legal environment in this community, the e-Judiciary service acts as a portal for safe-keeping of judicial information. Such a system also serves as a platform for the administration of minor offences that are solved by the traditional courts. Furthermore, it provides a better working environment for traditional judicial leaders and eliminates the difficulty of accessing legal information by the rest of the community. Through the availability and use of the service, community members are provided with understanding and knowledge about judiciary operations and services in their community.
- Full Text:
- Date Issued: 2010
- Authors: Scott, Mfundo Shakes
- Date: 2010
- Subjects: Digital divide -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , User interfaces (Computer systems)
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11390 , http://hdl.handle.net/10353/275 , Digital divide -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , User interfaces (Computer systems)
- Description: One of the factors that contribute towards slow rural development is the presence of the digital divide. An area where the digital divide is still prevalent is the administration of justice within traditional contexts. One of the areas affected by this problem is the Dwesa rural community, situated on the Wild Coast of the former homeland of Transkei, in the Eastern Cape Province of South Africa. To address this problem for the Dwesa community, a research project on developing and implementing an e-Judiciary service was undertaken. The primary objective of this project was to develop a web application to support traditional justice administration in the Dwesa community. Due to the lack of a proper legal environment in this community, the e-Judiciary service acts as a portal for safe-keeping of judicial information. Such a system also serves as a platform for the administration of minor offences that are solved by the traditional courts. Furthermore, it provides a better working environment for traditional judicial leaders and eliminates the difficulty of accessing legal information by the rest of the community. Through the availability and use of the service, community members are provided with understanding and knowledge about judiciary operations and services in their community.
- Full Text:
- Date Issued: 2010
Land use, compensational justice and energy resource extraction in Nigeria: a socio-historical study of petroleum and coal mining communities
- Authors: Umejesi, Ikechukwu
- Date: 2010
- Subjects: Compensation (Law) -- Nigeria , Right of property -- Nigeria , Mines and mineral resources -- Nigeria , Coal mines and mining -- Nigeria
- Language: English
- Type: Thesis , Doctoral , PhD (Sociology)
- Identifier: vital:11950 , http://hdl.handle.net/10353/344 , Compensation (Law) -- Nigeria , Right of property -- Nigeria , Mines and mineral resources -- Nigeria , Coal mines and mining -- Nigeria
- Description: Scholarly and public analyses of state-community conflict in resource-rich communities, especially in Nigeria, often portray the compensational practices of the state and extractive enterprises as unjust and unsustainable. According to this view, at least three issues foreground the “unjustness”, namely: a) Inadequate compensation of land owners when land is expropriated or degraded in the process of natural resource exploration and production; b) inadequate periodic rents paid by extractive firms to land owners; and c) lack of, or inadequate socio-economic infrastructure in the host communities of extractive operations. Most analysts have therefore argued for a revamp of the compensation system and have presented the inadequacy of compensation as the underlying cause of conflict in Nigeria‟s mining communities (see Frynas, 2000b:208; Okoji, 2002:205). This thesis subjects the compensation discourse to a closer examination, especially against the backdrop of underdevelopment, pervasive poverty, environmental damage and continuing corporate-community conflict in Nigeria‟s resource-rich rural communities. The main argument is that, because of some of its underlying neoliberal assumptions, much of the compensation discourse is flawed – which is why the discourse obscures the true character of state-community and corporate-community conflict. This more so, because the discourse relies mainly on post-colonial (that is, post-1960) experiences and contemporary advocacy literature, ignores the interplay between history and contemporary developments in state-community relations, and treats compensation as an independent variable. Drawing on the concept of collective memory, and utilising historical, ethnographic and survey data from two of Nigeria‟s oldest petroleum and coal-mining communities, the thesis examines how the evolution of the Nigerian state and collective memory about aspects of that evolution have shaped state-community relations in the extractive sector. It situates state- iii community resource-related conflict within the wider socio-historical matrix of state and community contestations for ecological and natural resource sovereignty. The key finding of the thesis is that within the context of socio-ecological rights, compensation demands by local communities are textured. In the case of the communities selected for the study, such demands are often made outside, rather than within, local ethnographic ideas of “justness” and “fairness”. Hence, land-related grievances associated with natural resource extraction persist, regardless of whether or not local demands for compensation are “adequately” met by the state and extractive corporations. The thesis enriches and extends our understanding of natural resource conflict by privileging both the sociological and historical contexts of the conflict and raising questions about the dominance the state enjoys over local communities and indigenous ecological spaces.
- Full Text:
- Date Issued: 2010
- Authors: Umejesi, Ikechukwu
- Date: 2010
- Subjects: Compensation (Law) -- Nigeria , Right of property -- Nigeria , Mines and mineral resources -- Nigeria , Coal mines and mining -- Nigeria
- Language: English
- Type: Thesis , Doctoral , PhD (Sociology)
- Identifier: vital:11950 , http://hdl.handle.net/10353/344 , Compensation (Law) -- Nigeria , Right of property -- Nigeria , Mines and mineral resources -- Nigeria , Coal mines and mining -- Nigeria
- Description: Scholarly and public analyses of state-community conflict in resource-rich communities, especially in Nigeria, often portray the compensational practices of the state and extractive enterprises as unjust and unsustainable. According to this view, at least three issues foreground the “unjustness”, namely: a) Inadequate compensation of land owners when land is expropriated or degraded in the process of natural resource exploration and production; b) inadequate periodic rents paid by extractive firms to land owners; and c) lack of, or inadequate socio-economic infrastructure in the host communities of extractive operations. Most analysts have therefore argued for a revamp of the compensation system and have presented the inadequacy of compensation as the underlying cause of conflict in Nigeria‟s mining communities (see Frynas, 2000b:208; Okoji, 2002:205). This thesis subjects the compensation discourse to a closer examination, especially against the backdrop of underdevelopment, pervasive poverty, environmental damage and continuing corporate-community conflict in Nigeria‟s resource-rich rural communities. The main argument is that, because of some of its underlying neoliberal assumptions, much of the compensation discourse is flawed – which is why the discourse obscures the true character of state-community and corporate-community conflict. This more so, because the discourse relies mainly on post-colonial (that is, post-1960) experiences and contemporary advocacy literature, ignores the interplay between history and contemporary developments in state-community relations, and treats compensation as an independent variable. Drawing on the concept of collective memory, and utilising historical, ethnographic and survey data from two of Nigeria‟s oldest petroleum and coal-mining communities, the thesis examines how the evolution of the Nigerian state and collective memory about aspects of that evolution have shaped state-community relations in the extractive sector. It situates state- iii community resource-related conflict within the wider socio-historical matrix of state and community contestations for ecological and natural resource sovereignty. The key finding of the thesis is that within the context of socio-ecological rights, compensation demands by local communities are textured. In the case of the communities selected for the study, such demands are often made outside, rather than within, local ethnographic ideas of “justness” and “fairness”. Hence, land-related grievances associated with natural resource extraction persist, regardless of whether or not local demands for compensation are “adequately” met by the state and extractive corporations. The thesis enriches and extends our understanding of natural resource conflict by privileging both the sociological and historical contexts of the conflict and raising questions about the dominance the state enjoys over local communities and indigenous ecological spaces.
- Full Text:
- Date Issued: 2010
Local economic development: a case study of the Blue Crane Route Municipality, Eastern Cape, South Africa
- Authors: Boose, Refuoe
- Date: 2010
- Subjects: Local government -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Rural-urban relations -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Geography)
- Identifier: vital:11509 , http://hdl.handle.net/10353/248 , Local government -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Rural-urban relations -- South Africa -- Eastern Cape
- Description: Local economic development (LED) in the countries of the North is a voluntary activity of local government, in South Africa it is a mandatory activity. The purpose of LED is to build the capacity of a local area to improve its economic future and the quality of life for all. While local governments in South Africa are currently engaged with the concept of LED which is seen as a tool through which to achieve sustainable development, it is now recognized that there exists economic, social and environmental interdependence between rural and urban areas and a need for a balanced and mutually supportive approach to development of the rural and urban areas. Adopting the Rural-Urban, Economic and Enterprise Development (RUEED) concept, this study highlights the challenges and development problems experienced by the deep rural and urban communities in the implementation of LED activities within the Blue Crane Route Municipality (BCRM) due to the lack of social, economic and environmental sustainability and rural-urban linkages. This study located in the Blue Crane Route Municipality in the Eastern Cape, seeks to investigate and recommend a map or strategies linking together the urban communities with the poorer neighbourhoods in LED activities. The intensive research design that incorporates the case study method was used to achieve the objectives of this study. The empirical findings of the research indicate that the concept of rural-urban linkages is not an adopted strategy in implementing development programmes resulting in deep rural communities being excluded in LED activities initiated within the Blue Crane Route Municipality. The findings also reveal that the creation of employment opportunities and improvement in the standard of living are important dimensions of LED and rural-urban linkages. This study therefore recommends the adoption of a new perspective referred to as the rural-urban linkages for LED and the consideration of economic, social and environmental complementaries that exist between rural and urban areas in the Blue Crane Route Municipality. The study further indicates that it is critical that the LED policy and interventions reflect the existing patterns of interactions between the rural and urban areas of the Municipality.
- Full Text:
- Date Issued: 2010
- Authors: Boose, Refuoe
- Date: 2010
- Subjects: Local government -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Rural-urban relations -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Geography)
- Identifier: vital:11509 , http://hdl.handle.net/10353/248 , Local government -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Rural-urban relations -- South Africa -- Eastern Cape
- Description: Local economic development (LED) in the countries of the North is a voluntary activity of local government, in South Africa it is a mandatory activity. The purpose of LED is to build the capacity of a local area to improve its economic future and the quality of life for all. While local governments in South Africa are currently engaged with the concept of LED which is seen as a tool through which to achieve sustainable development, it is now recognized that there exists economic, social and environmental interdependence between rural and urban areas and a need for a balanced and mutually supportive approach to development of the rural and urban areas. Adopting the Rural-Urban, Economic and Enterprise Development (RUEED) concept, this study highlights the challenges and development problems experienced by the deep rural and urban communities in the implementation of LED activities within the Blue Crane Route Municipality (BCRM) due to the lack of social, economic and environmental sustainability and rural-urban linkages. This study located in the Blue Crane Route Municipality in the Eastern Cape, seeks to investigate and recommend a map or strategies linking together the urban communities with the poorer neighbourhoods in LED activities. The intensive research design that incorporates the case study method was used to achieve the objectives of this study. The empirical findings of the research indicate that the concept of rural-urban linkages is not an adopted strategy in implementing development programmes resulting in deep rural communities being excluded in LED activities initiated within the Blue Crane Route Municipality. The findings also reveal that the creation of employment opportunities and improvement in the standard of living are important dimensions of LED and rural-urban linkages. This study therefore recommends the adoption of a new perspective referred to as the rural-urban linkages for LED and the consideration of economic, social and environmental complementaries that exist between rural and urban areas in the Blue Crane Route Municipality. The study further indicates that it is critical that the LED policy and interventions reflect the existing patterns of interactions between the rural and urban areas of the Municipality.
- Full Text:
- Date Issued: 2010
Manure production and nutrient management in pasture-based dairy production systems
- Authors: Svinurai, Walter
- Date: 2010
- Subjects: Manures , Nitrogen -- Metabolism , Aloe -- South Africa , Pine bark , Pastures , Dairy cattle -- Nutrition , Dairy cattle -- Management , Dairy cattle -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11812 , http://hdl.handle.net/10353/475 , Manures , Nitrogen -- Metabolism , Aloe -- South Africa , Pine bark , Pastures , Dairy cattle -- Nutrition , Dairy cattle -- Management , Dairy cattle -- Feeding and feeds
- Description: Manure production and nutrient management in pasture-based dairy production systems by Walter Svinurai The effect of dietary treatments on nutrient excretion was determined and an attempt to improving the retention of excreted nitrogen in stored manure using Aloe ferox leaf gel (AFLG) and pine bark was conducted at a pasture-based dairy farm. The animal mass-balance method was used to determine nutrient excretion by cows fed on three dietary treatments, Lolium perrene-based treatment (LP), Lolium multiforium-based treatment (LM) and Lolium perenne- Trifolium repens -based treatment (LTF). In separate experiments, slurry from dairy cows fed LM was amended with AFLG and pine bark at concentrations of 25, 50, 75 and 100 g/l and stored under anaerobic conditions for 16 days. The highest and lowest excretions of N, P and K were observed in LM and LP treatments, respectively. Increasing dietary N improved K and N retention in milk and, consequently increased milk urea nitrogen (MUN) and N excretion (P < 0.05). The concentrations of AFLG affected N and P retention in manure (P < 0.05). The highest retention in total Kjeldahl nitrogen (TKN) of the initial was 42% AFLG at 25g/l inclusion rate. Ammonium nitrogen (AMN) concentration increased significantly due to the interactive effect of AFLG inclusion rate and time. Pine bark powder significantly improved N and P retention in manure at all concentrations. The retention in TKN was higher (P < 0.05) at 25g/l pine bark powder than other concentrations. The interaction effect of inclusion rate and time increased iii AMN (P < 0.05). Dietary treatments significantly affected nutrient excretion, and AFLG and pine bark considerably improved N retention in stored slurry. Findings from the filed trial suggest the need for more attention on managing dietary nutrients in the post-rainy and cool-dry season when growth of pasture influenced choice of dietary treatments that led to high nutrient excretion. Field simulation of the additives to determine their efficacy and environmental hazards was recommended.
- Full Text:
- Date Issued: 2010
- Authors: Svinurai, Walter
- Date: 2010
- Subjects: Manures , Nitrogen -- Metabolism , Aloe -- South Africa , Pine bark , Pastures , Dairy cattle -- Nutrition , Dairy cattle -- Management , Dairy cattle -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11812 , http://hdl.handle.net/10353/475 , Manures , Nitrogen -- Metabolism , Aloe -- South Africa , Pine bark , Pastures , Dairy cattle -- Nutrition , Dairy cattle -- Management , Dairy cattle -- Feeding and feeds
- Description: Manure production and nutrient management in pasture-based dairy production systems by Walter Svinurai The effect of dietary treatments on nutrient excretion was determined and an attempt to improving the retention of excreted nitrogen in stored manure using Aloe ferox leaf gel (AFLG) and pine bark was conducted at a pasture-based dairy farm. The animal mass-balance method was used to determine nutrient excretion by cows fed on three dietary treatments, Lolium perrene-based treatment (LP), Lolium multiforium-based treatment (LM) and Lolium perenne- Trifolium repens -based treatment (LTF). In separate experiments, slurry from dairy cows fed LM was amended with AFLG and pine bark at concentrations of 25, 50, 75 and 100 g/l and stored under anaerobic conditions for 16 days. The highest and lowest excretions of N, P and K were observed in LM and LP treatments, respectively. Increasing dietary N improved K and N retention in milk and, consequently increased milk urea nitrogen (MUN) and N excretion (P < 0.05). The concentrations of AFLG affected N and P retention in manure (P < 0.05). The highest retention in total Kjeldahl nitrogen (TKN) of the initial was 42% AFLG at 25g/l inclusion rate. Ammonium nitrogen (AMN) concentration increased significantly due to the interactive effect of AFLG inclusion rate and time. Pine bark powder significantly improved N and P retention in manure at all concentrations. The retention in TKN was higher (P < 0.05) at 25g/l pine bark powder than other concentrations. The interaction effect of inclusion rate and time increased iii AMN (P < 0.05). Dietary treatments significantly affected nutrient excretion, and AFLG and pine bark considerably improved N retention in stored slurry. Findings from the filed trial suggest the need for more attention on managing dietary nutrients in the post-rainy and cool-dry season when growth of pasture influenced choice of dietary treatments that led to high nutrient excretion. Field simulation of the additives to determine their efficacy and environmental hazards was recommended.
- Full Text:
- Date Issued: 2010
Maximization of power in randomized clinical trials using the minimization treatment allocation technique
- Authors: Marange, Chioneso Show
- Date: 2010
- Subjects: Clinical trials -- Statistical methods , Statistical hypothesis testing , Regression analysis , Logistic distribution , Estimation theory
- Language: English
- Type: Thesis , Masters , MSc (Biostatistics and Epidemiology)
- Identifier: vital:11777 , http://hdl.handle.net/10353/399 , Clinical trials -- Statistical methods , Statistical hypothesis testing , Regression analysis , Logistic distribution , Estimation theory
- Description: Generally the primary goal of randomized clinical trials (RCT) is to make comparisons among two or more treatments hence clinical investigators require the most appropriate treatment allocation procedure to yield reliable results regardless of whether the ultimate data suggest a clinically important difference between the treatments being studied. Although recommended by many researchers, the utilization of minimization has been seldom reported in randomized trials mainly because of the controversy surrounding the statistical efficiency in detecting treatment effect and its complexity in implementation. Methods: A SAS simulation code was designed for allocating patients into two different treatment groups. Categorical prognostic factors were used together with multi-level response variables and demonstration of how simulation of data can help to determine the power of the minimization technique was carried out using ordinal logistic regression models. Results: Several scenarios were simulated in this study. Within the selected scenarios, increasing the sample size significantly increased the power of detecting the treatment effect. This was contrary to the case when the probability of allocation was decreased. Power did not change when the probability of allocation given that the treatment groups are balanced was increased. The probability of allocation { } k P was seen to be the only one with a significant effect on treatment balance. Conclusion: Maximum power can be achieved with a sample of size 300 although a small sample of size 200 can be adequate to attain at least 80% power. In order to have maximum power, the probability of allocation should be fixed at 0.75 and set to 0.5 if the treatment groups are equally balanced.
- Full Text:
- Date Issued: 2010
- Authors: Marange, Chioneso Show
- Date: 2010
- Subjects: Clinical trials -- Statistical methods , Statistical hypothesis testing , Regression analysis , Logistic distribution , Estimation theory
- Language: English
- Type: Thesis , Masters , MSc (Biostatistics and Epidemiology)
- Identifier: vital:11777 , http://hdl.handle.net/10353/399 , Clinical trials -- Statistical methods , Statistical hypothesis testing , Regression analysis , Logistic distribution , Estimation theory
- Description: Generally the primary goal of randomized clinical trials (RCT) is to make comparisons among two or more treatments hence clinical investigators require the most appropriate treatment allocation procedure to yield reliable results regardless of whether the ultimate data suggest a clinically important difference between the treatments being studied. Although recommended by many researchers, the utilization of minimization has been seldom reported in randomized trials mainly because of the controversy surrounding the statistical efficiency in detecting treatment effect and its complexity in implementation. Methods: A SAS simulation code was designed for allocating patients into two different treatment groups. Categorical prognostic factors were used together with multi-level response variables and demonstration of how simulation of data can help to determine the power of the minimization technique was carried out using ordinal logistic regression models. Results: Several scenarios were simulated in this study. Within the selected scenarios, increasing the sample size significantly increased the power of detecting the treatment effect. This was contrary to the case when the probability of allocation was decreased. Power did not change when the probability of allocation given that the treatment groups are balanced was increased. The probability of allocation { } k P was seen to be the only one with a significant effect on treatment balance. Conclusion: Maximum power can be achieved with a sample of size 300 although a small sample of size 200 can be adequate to attain at least 80% power. In order to have maximum power, the probability of allocation should be fixed at 0.75 and set to 0.5 if the treatment groups are equally balanced.
- Full Text:
- Date Issued: 2010
Mobile phones interaction techniques for second economy people
- Authors: Edim, Azom Emmanuel
- Date: 2010
- Subjects: Rural development projects -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Cell phone systems -- South Africa -- Eastern Cape , User interfaces (Computer systems) , Human-computer interaction , Community development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Computer Science)
- Identifier: vital:11392 , http://hdl.handle.net/10353/519 , Rural development projects -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Cell phone systems -- South Africa -- Eastern Cape , User interfaces (Computer systems) , Human-computer interaction , Community development -- South Africa -- Eastern Cape
- Description: Second economy people in developing countries are people living in communities that are underserved in terms of basic amenities and social services. Due to literacy challenges and user accessibility problems in rural communities, it is often difficult to design user interfaces that conform to the capabilities and cultural experiences of low-literacy rural community users. Rural community users are technologically illiterate and lack the knowledge of the potential of information and communication technologies. In order to embrace new technology, users will need to perceive the user interface and application as useful and easy to interact with. This requires proper understanding of the users and their socio-cultural environment. This will enable the interfaces and interactions to conform to their behaviours, motivations as well as cultural experiences and preferences and thus enhance usability and user experience. Mobile phones have the potential to increase access to information and provide a platform for economic development in rural communities. Rural communities have economic potential in terms of agriculture and micro-enterprises. Information technology can be used to enhance socio-economic activities and improve rural livelihood. We conducted a study to design user interfaces for a mobile commerce application for micro-entrepreneurs in a rural community in South Africa. The aim of the study was to design mobile interfaces and interaction techniques that are easy to use and meet the cultural preferences and experiences of users who have little to no previous experience of mobile commerce technology. And also to explore the potentials of information technologies rural community users, and bring mobile added value services to rural micro-entrepreneurs. We applied a user-centred design approach in Dwesa community and used qualitative and quantitative research methods to collect data for the design of the user interfaces (graphic user interface and voice user interface) and mobile commerce application. We identified and used several interface elements to design and finally evaluate the graphical user interface. The statistics analysis of the evaluation results show that the users in the community have positive perception of the usefulness of the application, the ease of use and intention to use the application. Community users with no prior experience with this technology were able to learn and understand the interface, recorded minimum errors and a high level of v precision during task performance when they interacted with the shop-owner graphic user interface. The voice user interface designed in this study consists of two flavours (dual tone multi-frequency input and voice input) for rural users. The evaluation results show that community users recorded higher tasks successes and minimum errors with the dual tone multi-frequency input interface than the voice only input interface. Also, a higher percentage of users prefer the dual tone multi-frequency input interface. The t-Test statistical analysis performed on the tasks completion times and error rate show that there was significant statistical difference between the dual tone multi-frequency input interface and the voice input interface. The interfaces were easy to learn, understand and use. Properly designed user interfaces that meet the experience and capabilities of low-literacy users in rural areas will improve usability and users‟ experiences. Adaptation of interfaces to users‟ culture and preferences will enhance information services accessibility among different user groups in different regions. This will promote technology acceptance in rural communities for socio-economic benefits. The user interfaces presented in this study can be adapted to different cultures to provide similar services for marginalised communities in developing countries
- Full Text:
- Date Issued: 2010
- Authors: Edim, Azom Emmanuel
- Date: 2010
- Subjects: Rural development projects -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Cell phone systems -- South Africa -- Eastern Cape , User interfaces (Computer systems) , Human-computer interaction , Community development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Computer Science)
- Identifier: vital:11392 , http://hdl.handle.net/10353/519 , Rural development projects -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Cell phone systems -- South Africa -- Eastern Cape , User interfaces (Computer systems) , Human-computer interaction , Community development -- South Africa -- Eastern Cape
- Description: Second economy people in developing countries are people living in communities that are underserved in terms of basic amenities and social services. Due to literacy challenges and user accessibility problems in rural communities, it is often difficult to design user interfaces that conform to the capabilities and cultural experiences of low-literacy rural community users. Rural community users are technologically illiterate and lack the knowledge of the potential of information and communication technologies. In order to embrace new technology, users will need to perceive the user interface and application as useful and easy to interact with. This requires proper understanding of the users and their socio-cultural environment. This will enable the interfaces and interactions to conform to their behaviours, motivations as well as cultural experiences and preferences and thus enhance usability and user experience. Mobile phones have the potential to increase access to information and provide a platform for economic development in rural communities. Rural communities have economic potential in terms of agriculture and micro-enterprises. Information technology can be used to enhance socio-economic activities and improve rural livelihood. We conducted a study to design user interfaces for a mobile commerce application for micro-entrepreneurs in a rural community in South Africa. The aim of the study was to design mobile interfaces and interaction techniques that are easy to use and meet the cultural preferences and experiences of users who have little to no previous experience of mobile commerce technology. And also to explore the potentials of information technologies rural community users, and bring mobile added value services to rural micro-entrepreneurs. We applied a user-centred design approach in Dwesa community and used qualitative and quantitative research methods to collect data for the design of the user interfaces (graphic user interface and voice user interface) and mobile commerce application. We identified and used several interface elements to design and finally evaluate the graphical user interface. The statistics analysis of the evaluation results show that the users in the community have positive perception of the usefulness of the application, the ease of use and intention to use the application. Community users with no prior experience with this technology were able to learn and understand the interface, recorded minimum errors and a high level of v precision during task performance when they interacted with the shop-owner graphic user interface. The voice user interface designed in this study consists of two flavours (dual tone multi-frequency input and voice input) for rural users. The evaluation results show that community users recorded higher tasks successes and minimum errors with the dual tone multi-frequency input interface than the voice only input interface. Also, a higher percentage of users prefer the dual tone multi-frequency input interface. The t-Test statistical analysis performed on the tasks completion times and error rate show that there was significant statistical difference between the dual tone multi-frequency input interface and the voice input interface. The interfaces were easy to learn, understand and use. Properly designed user interfaces that meet the experience and capabilities of low-literacy users in rural areas will improve usability and users‟ experiences. Adaptation of interfaces to users‟ culture and preferences will enhance information services accessibility among different user groups in different regions. This will promote technology acceptance in rural communities for socio-economic benefits. The user interfaces presented in this study can be adapted to different cultures to provide similar services for marginalised communities in developing countries
- Full Text:
- Date Issued: 2010
Narrative play therapy and the journey of a boy diagnosed with a learning disability: a case study
- Authors: Topper, Kegan
- Date: 2010
- Subjects: Play therapy -- Case studies , Narrative therapy -- Case studies , Children with disabilities , Learning disabilities , Cognitive therapy for children , Play -- Psychological aspects
- Language: English
- Type: Thesis , Masters , M Soc Sc (C Psy)
- Identifier: vital:11854 , http://hdl.handle.net/10353/313 , Play therapy -- Case studies , Narrative therapy -- Case studies , Children with disabilities , Learning disabilities , Cognitive therapy for children , Play -- Psychological aspects
- Description: This study offers a detailed exploration of the personal narrative of a nine year old boy diagnosed with a learning disability, and explains how the nature of the therapeutic relationship facilitated shifts in his personal understandings of himself, others and the world. Children diagnosed with learning disabilities experience a range of challenges in their different life contexts, and particularly within the school context. This is often because of constant evaluation and surveillance from teachers, family members and peers, who define the child within rigid and limiting frameworks. Soon enough children diagnosed with learning disabilities develop problem-saturated narratives that can significantly influence their relationship with themselves and others. This is because the individualising effects of having a disability cause them to feel different or isolated from their peers. This study illustrates an eight session case study, facilitated by a narrative play therapy approach, between a counsellor, a child and his parents. The therapeutic encounters were intended to assist the child in moving away from problem-saturated narratives of incompetence and inferiority towards more preferred narratives that would positively influence his self esteem. Key words: learning disability, dyslexia, narrative, narrative therapy, identity, self esteem. Children Diagnosed with a Learning Disability Children who have been diagnosed with a learning disability often experience themselves and their world very differently from other children (Rodis, Garrod, & Boscardin, 2001). Within the educational system a considerable amount of pressure is placed on children to succeed. The educational discourse of achievement that professes itself to be the only direction from which a successful future can be attained, marginalizes and rejects those children whose knowledge and skills exist outside this rigid and oftentimes insensitive system of evaluation. As a result, children soon create problem saturated narratives, believing themselves to be the problem. However, in the last two decades there has been a move from reductionism to constructivism and as a result research in the field of learning disabilities has started to focus on children’s non-traditional strengths and talents, which are often misunderstood and ignored by schools. Armstrong (1987) sums it up as follows: The schools allow millions of imaginative kids to go unrecognised
- Full Text:
- Date Issued: 2010
- Authors: Topper, Kegan
- Date: 2010
- Subjects: Play therapy -- Case studies , Narrative therapy -- Case studies , Children with disabilities , Learning disabilities , Cognitive therapy for children , Play -- Psychological aspects
- Language: English
- Type: Thesis , Masters , M Soc Sc (C Psy)
- Identifier: vital:11854 , http://hdl.handle.net/10353/313 , Play therapy -- Case studies , Narrative therapy -- Case studies , Children with disabilities , Learning disabilities , Cognitive therapy for children , Play -- Psychological aspects
- Description: This study offers a detailed exploration of the personal narrative of a nine year old boy diagnosed with a learning disability, and explains how the nature of the therapeutic relationship facilitated shifts in his personal understandings of himself, others and the world. Children diagnosed with learning disabilities experience a range of challenges in their different life contexts, and particularly within the school context. This is often because of constant evaluation and surveillance from teachers, family members and peers, who define the child within rigid and limiting frameworks. Soon enough children diagnosed with learning disabilities develop problem-saturated narratives that can significantly influence their relationship with themselves and others. This is because the individualising effects of having a disability cause them to feel different or isolated from their peers. This study illustrates an eight session case study, facilitated by a narrative play therapy approach, between a counsellor, a child and his parents. The therapeutic encounters were intended to assist the child in moving away from problem-saturated narratives of incompetence and inferiority towards more preferred narratives that would positively influence his self esteem. Key words: learning disability, dyslexia, narrative, narrative therapy, identity, self esteem. Children Diagnosed with a Learning Disability Children who have been diagnosed with a learning disability often experience themselves and their world very differently from other children (Rodis, Garrod, & Boscardin, 2001). Within the educational system a considerable amount of pressure is placed on children to succeed. The educational discourse of achievement that professes itself to be the only direction from which a successful future can be attained, marginalizes and rejects those children whose knowledge and skills exist outside this rigid and oftentimes insensitive system of evaluation. As a result, children soon create problem saturated narratives, believing themselves to be the problem. However, in the last two decades there has been a move from reductionism to constructivism and as a result research in the field of learning disabilities has started to focus on children’s non-traditional strengths and talents, which are often misunderstood and ignored by schools. Armstrong (1987) sums it up as follows: The schools allow millions of imaginative kids to go unrecognised
- Full Text:
- Date Issued: 2010
Neotectonics and its applications for the exploration of groundwater in the fractured Karoo aquifers in the Eastern Cape,South Africa
- Authors: Madi, Kakaba
- Date: 2010
- Subjects: Water well drilling -- South Africa -- Eastern Cape , Aquifers -- South Africa -- Eastern Cape , Water -- supply engineering -- South Africa -- Eastern Cape , Prospecting -- Geophysical methods , Groundwater -- Research -- Methodology
- Language: English
- Type: Thesis , Masters , MSc (Geology)
- Identifier: vital:11523 , http://hdl.handle.net/10353/362 , Water well drilling -- South Africa -- Eastern Cape , Aquifers -- South Africa -- Eastern Cape , Water -- supply engineering -- South Africa -- Eastern Cape , Prospecting -- Geophysical methods , Groundwater -- Research -- Methodology
- Description: This study is part of an NRF sponsored research project entitled “Neotectonics and its applications for the exploration of groundwater in the fractured Karoo aquifers in the Eastern Cape” under the NRF Niche area of Water Resources Management and Sustainable Development in the Eastern Cape Province. The identification of relatively highly productive wells in the Karoo fractured aquifers is extremely difficult. This study aims to identify neotectonic zones and lower stress fields, and apply the results to groundwater exploration in the Eastern Cape Province. The methodologies adopted in this study include: a comprehensive literature review, extensive field mapping and investigation such as road cuts, sampling for laboratory studies, examination of seismic data, study of hot and ordinary springs, and interpretation of aerial photography and satellite images. Three main neotectonic belts were identified in the Eastern Cape (southern neotectonic belt, northern neotectonic belt and eastern neotectonic belt) based on literature review and field interpretations. The southern neotectonic belt (from the Cape Fold Belt to the lower Beaufort Group boundary) is characterized by the reactivation of the Coega-Bavianskloof and Sauer faults, the presence of a hot spring near Fort Beaufort, the slickenlines and discrete slickenlines and specifically the seismic events that were recorded in the Eastern Cape from 1850 to 2007. In this southern neotectonic belt the remote sensing has also revealed the presence of the Fort Beaufort fracture, the quartz veins seen in some dolerites and the different vegetation types along it may indicate that this fracture is possibly a fault; moreover the Quaternary sediments and weathered dolerites indicate that the Fort iii Beaufort fracture is characterized by groundwater circulation and accordingly is a good target for groundwater exploration, this fracture is a post-Karoo structure and possibly a neotectonic feature. In addition, the kaolin deposit, chiefly developed in the Dwyka tillite near Grahamstown is clearly controlled by neotectonic fracture zones. The northern neotectonic belt near the country of Lesotho is marked by the presence of the Senqu seismotectonic regime and hot springs. The Quaternary Amatole-Swaziland (formerly Ciskei-Swaziland) axis of uplift makes the eastern part of the province the third neotectonic zone, the asymmetric meanders of the Mbashe river in the vicinity of Qunu near Mthatha derived possibly from this Quaternary uplift; this asymmetric feature of meanders implies that the river has tried to maintain stability of its valley where tilting occurred. Within these neotectonic belts the central part of the Eastern Cape may be considered a static and inactive belt. A northwesterly trend for the maximum principal compresssional stress predominates in the Eastern Cape and is correlated with the present major structural control of the province. The current stress regime determination was derived from faults, joints and quartz veins only on kaolin deposits. Systematic joints reflect regional tectonic stress trajectories at the time of fracturing. Discharge rates of groundwater from boreholes as provided by the Department of Water and Forestry were used to confirm and predict water exploration targets. The region of Tabankulu (near Kwazulu Natal) in the northern neotectonic belt has remarkable discharge rates of groundwater (11.1 l/s, 4.65 l/s, 6.49 l/s, 42 l/s). The region of Mthatha, nearly surrounding the Amatole-Swaziland axis (former Ciskei-Swaziland iv axis) of uplift which might have generated some new faults, has a number of springs. These two regions should serve as case studies for future research. Apart from these two regions, two others regions can be considered as case studies for future groundwater exploration targets: the Bath Farm hot spring near the Fort Beaufort neotectonic fault and the vicinity of what is known as the Fort Beaufort fracture near Teba and Cimezile villages 20km north west of Fort Beaufort. It is concluded that the study of neotectonics and stress fields may be a useful tool for groundwater exploration in the Karoo fractured aquifers in the Eastern Cape, and in similar regions elsewhere in South Africa and in Africa.
- Full Text:
- Date Issued: 2010
- Authors: Madi, Kakaba
- Date: 2010
- Subjects: Water well drilling -- South Africa -- Eastern Cape , Aquifers -- South Africa -- Eastern Cape , Water -- supply engineering -- South Africa -- Eastern Cape , Prospecting -- Geophysical methods , Groundwater -- Research -- Methodology
- Language: English
- Type: Thesis , Masters , MSc (Geology)
- Identifier: vital:11523 , http://hdl.handle.net/10353/362 , Water well drilling -- South Africa -- Eastern Cape , Aquifers -- South Africa -- Eastern Cape , Water -- supply engineering -- South Africa -- Eastern Cape , Prospecting -- Geophysical methods , Groundwater -- Research -- Methodology
- Description: This study is part of an NRF sponsored research project entitled “Neotectonics and its applications for the exploration of groundwater in the fractured Karoo aquifers in the Eastern Cape” under the NRF Niche area of Water Resources Management and Sustainable Development in the Eastern Cape Province. The identification of relatively highly productive wells in the Karoo fractured aquifers is extremely difficult. This study aims to identify neotectonic zones and lower stress fields, and apply the results to groundwater exploration in the Eastern Cape Province. The methodologies adopted in this study include: a comprehensive literature review, extensive field mapping and investigation such as road cuts, sampling for laboratory studies, examination of seismic data, study of hot and ordinary springs, and interpretation of aerial photography and satellite images. Three main neotectonic belts were identified in the Eastern Cape (southern neotectonic belt, northern neotectonic belt and eastern neotectonic belt) based on literature review and field interpretations. The southern neotectonic belt (from the Cape Fold Belt to the lower Beaufort Group boundary) is characterized by the reactivation of the Coega-Bavianskloof and Sauer faults, the presence of a hot spring near Fort Beaufort, the slickenlines and discrete slickenlines and specifically the seismic events that were recorded in the Eastern Cape from 1850 to 2007. In this southern neotectonic belt the remote sensing has also revealed the presence of the Fort Beaufort fracture, the quartz veins seen in some dolerites and the different vegetation types along it may indicate that this fracture is possibly a fault; moreover the Quaternary sediments and weathered dolerites indicate that the Fort iii Beaufort fracture is characterized by groundwater circulation and accordingly is a good target for groundwater exploration, this fracture is a post-Karoo structure and possibly a neotectonic feature. In addition, the kaolin deposit, chiefly developed in the Dwyka tillite near Grahamstown is clearly controlled by neotectonic fracture zones. The northern neotectonic belt near the country of Lesotho is marked by the presence of the Senqu seismotectonic regime and hot springs. The Quaternary Amatole-Swaziland (formerly Ciskei-Swaziland) axis of uplift makes the eastern part of the province the third neotectonic zone, the asymmetric meanders of the Mbashe river in the vicinity of Qunu near Mthatha derived possibly from this Quaternary uplift; this asymmetric feature of meanders implies that the river has tried to maintain stability of its valley where tilting occurred. Within these neotectonic belts the central part of the Eastern Cape may be considered a static and inactive belt. A northwesterly trend for the maximum principal compresssional stress predominates in the Eastern Cape and is correlated with the present major structural control of the province. The current stress regime determination was derived from faults, joints and quartz veins only on kaolin deposits. Systematic joints reflect regional tectonic stress trajectories at the time of fracturing. Discharge rates of groundwater from boreholes as provided by the Department of Water and Forestry were used to confirm and predict water exploration targets. The region of Tabankulu (near Kwazulu Natal) in the northern neotectonic belt has remarkable discharge rates of groundwater (11.1 l/s, 4.65 l/s, 6.49 l/s, 42 l/s). The region of Mthatha, nearly surrounding the Amatole-Swaziland axis (former Ciskei-Swaziland iv axis) of uplift which might have generated some new faults, has a number of springs. These two regions should serve as case studies for future research. Apart from these two regions, two others regions can be considered as case studies for future groundwater exploration targets: the Bath Farm hot spring near the Fort Beaufort neotectonic fault and the vicinity of what is known as the Fort Beaufort fracture near Teba and Cimezile villages 20km north west of Fort Beaufort. It is concluded that the study of neotectonics and stress fields may be a useful tool for groundwater exploration in the Karoo fractured aquifers in the Eastern Cape, and in similar regions elsewhere in South Africa and in Africa.
- Full Text:
- Date Issued: 2010
Phishing within e-commerce: reducing the risk, increasing the trust
- Authors: Megaw, Gregory M
- Date: 2010
- Subjects: Phishing , Identity theft -- Prevention , Electronic commerce , Computer security , Internet -- Safety measures
- Language: English
- Type: Thesis , Masters , MCom (Information Systems)
- Identifier: vital:11131 , http://hdl.handle.net/10353/376 , Phishing , Identity theft -- Prevention , Electronic commerce , Computer security , Internet -- Safety measures
- Description: E-Commerce has been plagued with problems since its inception and this study examines one of these problems: The lack of user trust in E-Commerce created by the risk of phishing. Phishing has grown exponentially together with the expansion of the Internet. This growth and the advancement of technology has not only benefited honest Internet users, but has enabled criminals to increase their effectiveness which has caused considerable damage to this budding area of commerce. Moreover, it has negatively impacted both the user and online business in breaking down the trust relationship between them. In an attempt to explore this problem, the following was considered: First, E-Commerce’s vulnerability to phishing attacks. By referring to the Common Criteria Security Model, various critical security areas within E-Commerce are identified, as well as the areas of vulnerability and weakness. Second, the methods and techniques used in phishing, such as phishing e-mails, websites and addresses, distributed attacks and redirected attacks, as well as the data that phishers seek to obtain, are examined. Furthermore, the way to reduce the risk of phishing and in turn increase the trust between users and websites is identified. Here the importance of Trust and the Uncertainty Reduction Theory plus the fine balance between trust and control is explored. Finally, the study presents Critical Success Factors that aid in phishing prevention and control, these being: User Authentication, Website Authentication, E-mail Authentication, Data Cryptography, Communication, and Active Risk Mitigation.
- Full Text:
- Date Issued: 2010
- Authors: Megaw, Gregory M
- Date: 2010
- Subjects: Phishing , Identity theft -- Prevention , Electronic commerce , Computer security , Internet -- Safety measures
- Language: English
- Type: Thesis , Masters , MCom (Information Systems)
- Identifier: vital:11131 , http://hdl.handle.net/10353/376 , Phishing , Identity theft -- Prevention , Electronic commerce , Computer security , Internet -- Safety measures
- Description: E-Commerce has been plagued with problems since its inception and this study examines one of these problems: The lack of user trust in E-Commerce created by the risk of phishing. Phishing has grown exponentially together with the expansion of the Internet. This growth and the advancement of technology has not only benefited honest Internet users, but has enabled criminals to increase their effectiveness which has caused considerable damage to this budding area of commerce. Moreover, it has negatively impacted both the user and online business in breaking down the trust relationship between them. In an attempt to explore this problem, the following was considered: First, E-Commerce’s vulnerability to phishing attacks. By referring to the Common Criteria Security Model, various critical security areas within E-Commerce are identified, as well as the areas of vulnerability and weakness. Second, the methods and techniques used in phishing, such as phishing e-mails, websites and addresses, distributed attacks and redirected attacks, as well as the data that phishers seek to obtain, are examined. Furthermore, the way to reduce the risk of phishing and in turn increase the trust between users and websites is identified. Here the importance of Trust and the Uncertainty Reduction Theory plus the fine balance between trust and control is explored. Finally, the study presents Critical Success Factors that aid in phishing prevention and control, these being: User Authentication, Website Authentication, E-mail Authentication, Data Cryptography, Communication, and Active Risk Mitigation.
- Full Text:
- Date Issued: 2010
Population biology and aspects of the socio-spatial organisation of the woodland dormouse Graphiurus Murinus (Desmaret, 1822) in the Great Fish River Reserve, South Africa
- Madikiza, Zimkitha Josephine Kimberly
- Authors: Madikiza, Zimkitha Josephine Kimberly
- Date: 2010
- Subjects: Dormice , Mice , Muridae , Spatial behavior , Territoriality (Zoology) , Crowding stress
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11788 , http://hdl.handle.net/10353/443 , Dormice , Mice , Muridae , Spatial behavior , Territoriality (Zoology) , Crowding stress
- Description: The population biology and socio-spatial organisation of the woodland dormouse, Graphiurus murinus (Desmarest, 1822), was investigated in a riverine forest at the Great Fish River Reserve (GFRR), South Africa. Data were collected by means of a monthly live trapping and nestbox monitoring programme. Between February 2006 and June 2007, 75 woodland dormice were trapped and/or found in nestboxes and marked: these were 39 adults (13 males, 21 females, five undetermined) and 36 juveniles (five males, 14 females, 17 undetermined). The population showed a steady increase from June 2006–November 2006 and a peak in December 2006–January 2007 as a result of the influx of juveniles. The minimum number of dormice known to be alive (MNA) varied between 40 in December 2006– January 2007 (summer), and a low of three in June 2007 (winter). The range in population density was therefore between 1.2 and 16 dormice per ha. Winter mortality and/or spring dispersal accounted for the disappearance of 55 percent of juveniles. The overall annual adult:juvenile ratio was 1.08. The overall sex ratio was 1.94 female per one male. In females, reproductive activity was observed from September 2006 to end January 2007. The pattern observed in males was similar, as dormice with descended testes were exclusively found from October to end January. Females gave birth during the second half of October to beginning of February. Litters (n = 11) consisted of an average (± SD) 3.73 ± 0.47 young. Over the study period, 27 dormice were trapped or found in nestboxes more than eight times, thus allowing me to estimate their home range size and the spatial overlap between these individuals. On average, dormouse home range size was 2,514 m2 (range: 319 – 4,863 m2). No difference was recorded between one-year old adults and older adults, or between all adults and juveniles. However, adult male dormice (3,989 m2, n = 5) had home ranges almost twice as large as females (2,091 m2, n = 9). No similar trend was found in juveniles. Intrasexual home range overlap was on average 62 percent in adult males, and 26 percent in adult females. However, females overlapped with more neighbouring female home ranges than did males with neighbouring male home ranges, so that, as for males, only small parts of female home ranges were really exclusive. On average, males overlapped a larger Abstract Ecology of woodland dormice M.Sc. Thesis 16 proportion (48 percent) of female home ranges than did females with neighbouring male home ranges (27 percent). In addition, males overlapped with significantly more female home ranges (7.8) than did females with male home ranges (4.9). Trapping success and nestbox data agree with the socio-ecological model. Females showed increased mobility during summer, more likely to find suitable nesting sites, and food for milk production during the reproductive season. The use of nestboxes, however, was constant throughout the year. In males, both the trapping success and nestbox use were higher during the mating season (spring), when an increased mobility and occupation of nestboxes probably increased the chances to locate and mate with (a) receptive female(s). Hence, food and (artificial) nest sites may constitute an important resource for females, whereas females seem to represent the main resource for males. Although food availability was not determined, a comparison of female and male distribution patterns provided interesting information on the mating system of woodland dormice. In GFRR, the dispersion pattern of female woodland dormice was “rather” clumped, i.e. females were non-territorial. As some females showed a dyadic intrasexual overlap of up to 90 percent, and population density was very high at the study site, this may indicate that food was very abundant and/or renewed rapidly. Based on the wide range of birth dates observed during the study period, females clearly come into oestrus at different times. In such circumstances (asynchronous sexual receptivity in females), the Female in Space and Time Hypothesis (Ims 1987a) predicts that males will be non-territorial and promiscuous. Live-trapping, nestbox use and home range data indeed suggested that male woodland dormice do not defend territories, but search for and aggregate around receptive females during the mating season.
- Full Text:
- Date Issued: 2010
- Authors: Madikiza, Zimkitha Josephine Kimberly
- Date: 2010
- Subjects: Dormice , Mice , Muridae , Spatial behavior , Territoriality (Zoology) , Crowding stress
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11788 , http://hdl.handle.net/10353/443 , Dormice , Mice , Muridae , Spatial behavior , Territoriality (Zoology) , Crowding stress
- Description: The population biology and socio-spatial organisation of the woodland dormouse, Graphiurus murinus (Desmarest, 1822), was investigated in a riverine forest at the Great Fish River Reserve (GFRR), South Africa. Data were collected by means of a monthly live trapping and nestbox monitoring programme. Between February 2006 and June 2007, 75 woodland dormice were trapped and/or found in nestboxes and marked: these were 39 adults (13 males, 21 females, five undetermined) and 36 juveniles (five males, 14 females, 17 undetermined). The population showed a steady increase from June 2006–November 2006 and a peak in December 2006–January 2007 as a result of the influx of juveniles. The minimum number of dormice known to be alive (MNA) varied between 40 in December 2006– January 2007 (summer), and a low of three in June 2007 (winter). The range in population density was therefore between 1.2 and 16 dormice per ha. Winter mortality and/or spring dispersal accounted for the disappearance of 55 percent of juveniles. The overall annual adult:juvenile ratio was 1.08. The overall sex ratio was 1.94 female per one male. In females, reproductive activity was observed from September 2006 to end January 2007. The pattern observed in males was similar, as dormice with descended testes were exclusively found from October to end January. Females gave birth during the second half of October to beginning of February. Litters (n = 11) consisted of an average (± SD) 3.73 ± 0.47 young. Over the study period, 27 dormice were trapped or found in nestboxes more than eight times, thus allowing me to estimate their home range size and the spatial overlap between these individuals. On average, dormouse home range size was 2,514 m2 (range: 319 – 4,863 m2). No difference was recorded between one-year old adults and older adults, or between all adults and juveniles. However, adult male dormice (3,989 m2, n = 5) had home ranges almost twice as large as females (2,091 m2, n = 9). No similar trend was found in juveniles. Intrasexual home range overlap was on average 62 percent in adult males, and 26 percent in adult females. However, females overlapped with more neighbouring female home ranges than did males with neighbouring male home ranges, so that, as for males, only small parts of female home ranges were really exclusive. On average, males overlapped a larger Abstract Ecology of woodland dormice M.Sc. Thesis 16 proportion (48 percent) of female home ranges than did females with neighbouring male home ranges (27 percent). In addition, males overlapped with significantly more female home ranges (7.8) than did females with male home ranges (4.9). Trapping success and nestbox data agree with the socio-ecological model. Females showed increased mobility during summer, more likely to find suitable nesting sites, and food for milk production during the reproductive season. The use of nestboxes, however, was constant throughout the year. In males, both the trapping success and nestbox use were higher during the mating season (spring), when an increased mobility and occupation of nestboxes probably increased the chances to locate and mate with (a) receptive female(s). Hence, food and (artificial) nest sites may constitute an important resource for females, whereas females seem to represent the main resource for males. Although food availability was not determined, a comparison of female and male distribution patterns provided interesting information on the mating system of woodland dormice. In GFRR, the dispersion pattern of female woodland dormice was “rather” clumped, i.e. females were non-territorial. As some females showed a dyadic intrasexual overlap of up to 90 percent, and population density was very high at the study site, this may indicate that food was very abundant and/or renewed rapidly. Based on the wide range of birth dates observed during the study period, females clearly come into oestrus at different times. In such circumstances (asynchronous sexual receptivity in females), the Female in Space and Time Hypothesis (Ims 1987a) predicts that males will be non-territorial and promiscuous. Live-trapping, nestbox use and home range data indeed suggested that male woodland dormice do not defend territories, but search for and aggregate around receptive females during the mating season.
- Full Text:
- Date Issued: 2010
Prevalence and risk factors for Helicobacter pylori transmission in the Eastern Cape Province application of immunological molecular and demographic methods
- Authors: Dube, Callote
- Date: 2010
- Subjects: Helicobacter pylori , Bacterial diseases , Gastritis -- Risk factors , Bacterial diseases -- Risk factors , Gram-negative bacteria , Gram-negative bacterial infections , Helicobacter , Helicobacter infections , Helicobacter pylori -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11262 , http://hdl.handle.net/10353/265 , Helicobacter pylori , Bacterial diseases , Gastritis -- Risk factors , Bacterial diseases -- Risk factors , Gram-negative bacteria , Gram-negative bacterial infections , Helicobacter , Helicobacter infections , Helicobacter pylori -- South Africa -- Eastern Cape
- Description: Helicobacter pylori (H. pylori) is a microaerophilic, Gram-negative motile curved rod that inhabits the gastric mucosa of the human stomach. The organism chronically infects billions of people worldwide and is one of the most genetically diverse of bacterial species. Infection with the organism potentially induces chronic gastritis and peptic ulcer disease. In addition, H. pylori plays a role in the etiology of gastric cancer and gastric MALT lymphoma. The risk of infection is increased in those living in the developing world, which has been ascribed to precarious hygiene standards, crowded households, and deficient sanitation common in this part of the world. Thus, the aim of this study was to identify the risk factors in the transmission of H. pylori in our environment, i.e. in Nkonkobe Municipality in the Eastern Cape Province, South Africa. Faecal samples were collected from 356 apparently healthy subjects, consisting of 168 males and 188 females aged from 3 months to 60 years (Mean = 31 years). A standardized questionnaire was applied, it described demographic characteristics including age, sex, household hygiene, socioeconomic status, area of residence, duration of stay in the area, sharing bath water, sharing tooth brush, habit of sucking thumb, medication currently being taken or medication taken within the past three months, source of water, type of toilet used, education and occupation. A sandwich-type enzyme immunoassay amplification technology (Amplified IDEIA TM Hp StAR TM , Oxoid, UK) was used to analyze the faecal samples for the detection of H. pylori antigens using monoclonal antibodies specific for H. pylori antigens. To assess the possibility of faecal oral route with tap water as an intermediary link, PCR targeting the ureC (glmM), a highly conserved gene in H. pylori ii was carried out to detect H. pylori DNA in faecal samples of already positive samples by HpSA test as well as in direct tap water used by the H. pylori positive subjects. QIAamp DNA stool mini kit was used to extract DNA from faecal samples. Tap water samples were then obtained using sterile bottles from areas inhabited by H. pylori positive subjects as determined by HpSA test and PCR. DNA extraction from water samples was done using UltraCleanTM Water DNA Isolation Kit (0.22μm) according to the manufacturer’s instructions. PCR with primers specific for H. pylori glmM gene was carried out with both positive and negative controls incorporated. Fisher’s exact test was used to assess the univariate association between H. pylori infection and the possible risk factors. Odds ratio (OR) and the corresponding 95 percent confidence interval (CI) were calculated to measure the strength of association using EPI INFO 3.41 package. P values of < .05 were required for significance. The precision rate of the diagnostic tests used was also determined. H. pylori antigen was detected in 316 of the 356 subjects giving an overall prevalence of 88.8 percent. Prevalence increased with age from 75.9 percent in children < 12 years age to 100 percent in the age group from 13 years to 24 years, also 100 percent prevalence of H. pylori was recorded in young adults aged 25-47 years and subjects aged 60 years (P < .05). H. pylori prevalence was higher in females than in males. Of 188 females who participated in the study, H. pylori antigen was detected in 172 (91.5 percent) versus 144 (85.7 percent) of 168 males (P > .05). Interestingly, H pylori antigen was detected more often (100 percent) in the high socioeconomic group than in those of low socioeconomic group (85.9 percent). Sixteen (66.7 percent) of twenty four faecal samples that had previously tested positive for the organism by HpSA test were confirmed positive by PCR. However none of the treated tap water samples tested positive for the organism by PCR. The present iii study revealed a high prevalence of H. pylori in faecal samples of asymptomatic individuals in the Nkonkobe Municipality, an indication of active infection. The obtained results also revealed that direct treated tap water might not be playing a crucial role in the oral transmission of H. pylori in the studied population.
- Full Text:
- Date Issued: 2010
- Authors: Dube, Callote
- Date: 2010
- Subjects: Helicobacter pylori , Bacterial diseases , Gastritis -- Risk factors , Bacterial diseases -- Risk factors , Gram-negative bacteria , Gram-negative bacterial infections , Helicobacter , Helicobacter infections , Helicobacter pylori -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11262 , http://hdl.handle.net/10353/265 , Helicobacter pylori , Bacterial diseases , Gastritis -- Risk factors , Bacterial diseases -- Risk factors , Gram-negative bacteria , Gram-negative bacterial infections , Helicobacter , Helicobacter infections , Helicobacter pylori -- South Africa -- Eastern Cape
- Description: Helicobacter pylori (H. pylori) is a microaerophilic, Gram-negative motile curved rod that inhabits the gastric mucosa of the human stomach. The organism chronically infects billions of people worldwide and is one of the most genetically diverse of bacterial species. Infection with the organism potentially induces chronic gastritis and peptic ulcer disease. In addition, H. pylori plays a role in the etiology of gastric cancer and gastric MALT lymphoma. The risk of infection is increased in those living in the developing world, which has been ascribed to precarious hygiene standards, crowded households, and deficient sanitation common in this part of the world. Thus, the aim of this study was to identify the risk factors in the transmission of H. pylori in our environment, i.e. in Nkonkobe Municipality in the Eastern Cape Province, South Africa. Faecal samples were collected from 356 apparently healthy subjects, consisting of 168 males and 188 females aged from 3 months to 60 years (Mean = 31 years). A standardized questionnaire was applied, it described demographic characteristics including age, sex, household hygiene, socioeconomic status, area of residence, duration of stay in the area, sharing bath water, sharing tooth brush, habit of sucking thumb, medication currently being taken or medication taken within the past three months, source of water, type of toilet used, education and occupation. A sandwich-type enzyme immunoassay amplification technology (Amplified IDEIA TM Hp StAR TM , Oxoid, UK) was used to analyze the faecal samples for the detection of H. pylori antigens using monoclonal antibodies specific for H. pylori antigens. To assess the possibility of faecal oral route with tap water as an intermediary link, PCR targeting the ureC (glmM), a highly conserved gene in H. pylori ii was carried out to detect H. pylori DNA in faecal samples of already positive samples by HpSA test as well as in direct tap water used by the H. pylori positive subjects. QIAamp DNA stool mini kit was used to extract DNA from faecal samples. Tap water samples were then obtained using sterile bottles from areas inhabited by H. pylori positive subjects as determined by HpSA test and PCR. DNA extraction from water samples was done using UltraCleanTM Water DNA Isolation Kit (0.22μm) according to the manufacturer’s instructions. PCR with primers specific for H. pylori glmM gene was carried out with both positive and negative controls incorporated. Fisher’s exact test was used to assess the univariate association between H. pylori infection and the possible risk factors. Odds ratio (OR) and the corresponding 95 percent confidence interval (CI) were calculated to measure the strength of association using EPI INFO 3.41 package. P values of < .05 were required for significance. The precision rate of the diagnostic tests used was also determined. H. pylori antigen was detected in 316 of the 356 subjects giving an overall prevalence of 88.8 percent. Prevalence increased with age from 75.9 percent in children < 12 years age to 100 percent in the age group from 13 years to 24 years, also 100 percent prevalence of H. pylori was recorded in young adults aged 25-47 years and subjects aged 60 years (P < .05). H. pylori prevalence was higher in females than in males. Of 188 females who participated in the study, H. pylori antigen was detected in 172 (91.5 percent) versus 144 (85.7 percent) of 168 males (P > .05). Interestingly, H pylori antigen was detected more often (100 percent) in the high socioeconomic group than in those of low socioeconomic group (85.9 percent). Sixteen (66.7 percent) of twenty four faecal samples that had previously tested positive for the organism by HpSA test were confirmed positive by PCR. However none of the treated tap water samples tested positive for the organism by PCR. The present iii study revealed a high prevalence of H. pylori in faecal samples of asymptomatic individuals in the Nkonkobe Municipality, an indication of active infection. The obtained results also revealed that direct treated tap water might not be playing a crucial role in the oral transmission of H. pylori in the studied population.
- Full Text:
- Date Issued: 2010
Prevalence of listeria pathogens in effluents of some wastewater treatment facilities in the Eastern Cape province of South Africa
- Odjadjare, Emmanuel Erufuare Onogwuwhenya
- Authors: Odjadjare, Emmanuel Erufuare Onogwuwhenya
- Date: 2010
- Subjects: Listeria -- South Africa -- Eastern Cape , Sewage -- Purification -- South Africa -- Eastern Cape , Effluent quality -- South Africa -- Eastern Cape , Water -- Pollution -- South Africa -- Eastern Cape , Water -- Purification -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Microbiology)
- Identifier: vital:11264 , http://hdl.handle.net/10353/246 , Listeria -- South Africa -- Eastern Cape , Sewage -- Purification -- South Africa -- Eastern Cape , Effluent quality -- South Africa -- Eastern Cape , Water -- Pollution -- South Africa -- Eastern Cape , Water -- Purification -- South Africa -- Eastern Cape
- Description: Wastewater discharges may contain health compromising pathogens and carcinogenic and/or chemical substances that could compromise the public health and impact negatively on the environment. The present study was conducted between August 2007 and July 2008 to evaluate the Listeria abundance (as free-living and plankton associated species) and physicochemical qualities of the final effluents of three wastewater treatment facilities in the Eastern Cape Province of South Africa selected to represent typical urban, peri-urban and rural communities and the impact of the discharged final effluents on their respective receiving watershed, as well as to elucidated the in vitro antibiotic susceptibilities and resistance genes profile of Listeria species isolated from the final effluents. The suitability of the secondary effluent of the urban treatment facility (as a case study) for use in agriculture and aquaculture with reference to recommended standards was also determined. Wastewater samples were collected from the raw sewage, secondary effluent, final treated effluent, discharge point, 500 m upstream discharge point, and 500 m downstream discharge point from all three locations on a monthly basis throughout the study period. Listeria abundance in the final effluents and the receiving watersheds varied between 2.9× 100 and 3.52 × 105cfu/ml across the sampled locations. Free-living listerial density across the sampled locations ranged between 0 and 3.2 × 103cfu/ml while counts of Listeria species attached to large (180 μm) planktons varied from 0 to 1.58 × 105 cfu/ml and those of the 60 and 20 μm categories were in the range of 0 to 1.32 × 103 cfu/ml and 0 to 2.82 × 105 cfu/ml respectively. Listeria abundance did not vary significantly with location and season; there was however, significant (P < 0.05; P < 0.01) variance in Listeria abundance with plankton sizes across the locations. Free-living Listeria species were more abundant in the rural and urban xii communities than plankton attached Listeria species; whereas the reverse was the case in the peri-urban community. Prevalence of Listeria in terms of total counts was 100 percent across all sampled locations. Free-living Listeria species showed prevalence ranging from 84-96 percent across the sampling locations; while Listeria species attached to large (180 μm) planktons exhibited prevalence ranging from 75 percent to 90 percent. The prevalence of medium-sized (60 μm) plankton associated Listeria species varied between 58 percent and 92.5 percent; whereas those of Listeria species attached to small (20 μm) planktons ranged from 65-100 percent across all three communities. Listeria prevalence was generally a reflection of the turbidity of the water system, with free-living Listeria species being more prevalent than plankton associated cells in the relatively less turbid rural and urban waters compared to the more turbid peri-urban waters where plankton attached cells were more prevalent in comparison with their free living counterparts The final treated effluent quality fell short of recommended standards for turbidity, chemical oxygen demand and phosphate across all three communities. In addition, the final effluent of the rural treatment plant also fell short of recommended standard for NO3, while that of the urban treatment plant did not comply with acceptable limits for dissolved oxygen and nitrite. Other physicochemical parameters were compliant with set standards after treatment. An inverse relationship was observed between chlorine residual and listerial density across the sampled facilities; the effect of chlorine was however not enough to eliminate the pathogen from the water systems. At the urban treatment plant and its receiving watershed, pH, temperature, EC, turbidity, TDS, DO, and nitrate varied significantly with season and sampling point (P < 0.05; P < 0.01). Salinity also varied significantly with sampling point (P < 0.01), while COD and nitrite varied significantly with season (P < 0.05). Although, the treated effluent fell within recommended water quality standard for pH, TDS, nitrate and nitrite, it fell short of stipulated standards for other parameters. Whereas the microbial quality of the secondary treated effluent at this (urban) facility fell short of recommended standard after secondary treatment, its physicochemical quality were generally compliant with recommended standards for reuse wastewater in agriculture and aquaculture. Listeria pathogens isolated from effluents of the rural wastewater facility were sensitive to 11 (55 percent) of the 20 test antibiotics, and showed varying (7-71 percent) levels of resistance to 8 antibiotics; whereas those isolated from the peri-urban community showed sensitivity to 6 (30 percent) of the 20 test antibiotics, and varying (6-94 percent) levels of resistance to 12 antibiotics; while the urban effluent isolates were sensitive to 3 (15 percent) of the 20 test antibiotics, and showed varying (4.5-91 percent) levels of resistance to 17 antibiotics. Multiple antibiotic resistances involving 78.5-100 percent of isolates and antibiotics combination ranging from 2-10 antibiotics was observed across the sampled locations. Penicillin G and ampicillin showed remarkably high (64-91 percent) phenotypic resistance across the three sampled facilities. Other antibiotics, to which isolates showed significant resistance, were linezolid (22-88 percent); erythromycin (43-94 percent) and sulphamethoxazole (7-94 percent). Two of the 14 Listeria strains isolated from the rural effluents were positive for ereA and sul1 antibiotic resistance genes; while sulII genes were detected in five of the 23 Listeria isolates from the urban effluent and none was detected in isolates from the peri-urban community. The presence of antimicrobial resistance genes in the isolates did not correlate with phenotypic antibiotic resistance. The current study demonstrated that Listeria pathogens easily survived the activated sludge treatment process as free-living and plankton attached entities and suggests that municipal wastewater treatment plants are a significant source of multiple resistant Listeria pathogens in the South African aquatic milieu. While the physicochemical quality of the urban final effluent suggests that it is a major source of pollution to the receiving watershed, the secondary effluent quality demonstrated a great potential for use in agriculture and aquaculture.
- Full Text:
- Date Issued: 2010
- Authors: Odjadjare, Emmanuel Erufuare Onogwuwhenya
- Date: 2010
- Subjects: Listeria -- South Africa -- Eastern Cape , Sewage -- Purification -- South Africa -- Eastern Cape , Effluent quality -- South Africa -- Eastern Cape , Water -- Pollution -- South Africa -- Eastern Cape , Water -- Purification -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Microbiology)
- Identifier: vital:11264 , http://hdl.handle.net/10353/246 , Listeria -- South Africa -- Eastern Cape , Sewage -- Purification -- South Africa -- Eastern Cape , Effluent quality -- South Africa -- Eastern Cape , Water -- Pollution -- South Africa -- Eastern Cape , Water -- Purification -- South Africa -- Eastern Cape
- Description: Wastewater discharges may contain health compromising pathogens and carcinogenic and/or chemical substances that could compromise the public health and impact negatively on the environment. The present study was conducted between August 2007 and July 2008 to evaluate the Listeria abundance (as free-living and plankton associated species) and physicochemical qualities of the final effluents of three wastewater treatment facilities in the Eastern Cape Province of South Africa selected to represent typical urban, peri-urban and rural communities and the impact of the discharged final effluents on their respective receiving watershed, as well as to elucidated the in vitro antibiotic susceptibilities and resistance genes profile of Listeria species isolated from the final effluents. The suitability of the secondary effluent of the urban treatment facility (as a case study) for use in agriculture and aquaculture with reference to recommended standards was also determined. Wastewater samples were collected from the raw sewage, secondary effluent, final treated effluent, discharge point, 500 m upstream discharge point, and 500 m downstream discharge point from all three locations on a monthly basis throughout the study period. Listeria abundance in the final effluents and the receiving watersheds varied between 2.9× 100 and 3.52 × 105cfu/ml across the sampled locations. Free-living listerial density across the sampled locations ranged between 0 and 3.2 × 103cfu/ml while counts of Listeria species attached to large (180 μm) planktons varied from 0 to 1.58 × 105 cfu/ml and those of the 60 and 20 μm categories were in the range of 0 to 1.32 × 103 cfu/ml and 0 to 2.82 × 105 cfu/ml respectively. Listeria abundance did not vary significantly with location and season; there was however, significant (P < 0.05; P < 0.01) variance in Listeria abundance with plankton sizes across the locations. Free-living Listeria species were more abundant in the rural and urban xii communities than plankton attached Listeria species; whereas the reverse was the case in the peri-urban community. Prevalence of Listeria in terms of total counts was 100 percent across all sampled locations. Free-living Listeria species showed prevalence ranging from 84-96 percent across the sampling locations; while Listeria species attached to large (180 μm) planktons exhibited prevalence ranging from 75 percent to 90 percent. The prevalence of medium-sized (60 μm) plankton associated Listeria species varied between 58 percent and 92.5 percent; whereas those of Listeria species attached to small (20 μm) planktons ranged from 65-100 percent across all three communities. Listeria prevalence was generally a reflection of the turbidity of the water system, with free-living Listeria species being more prevalent than plankton associated cells in the relatively less turbid rural and urban waters compared to the more turbid peri-urban waters where plankton attached cells were more prevalent in comparison with their free living counterparts The final treated effluent quality fell short of recommended standards for turbidity, chemical oxygen demand and phosphate across all three communities. In addition, the final effluent of the rural treatment plant also fell short of recommended standard for NO3, while that of the urban treatment plant did not comply with acceptable limits for dissolved oxygen and nitrite. Other physicochemical parameters were compliant with set standards after treatment. An inverse relationship was observed between chlorine residual and listerial density across the sampled facilities; the effect of chlorine was however not enough to eliminate the pathogen from the water systems. At the urban treatment plant and its receiving watershed, pH, temperature, EC, turbidity, TDS, DO, and nitrate varied significantly with season and sampling point (P < 0.05; P < 0.01). Salinity also varied significantly with sampling point (P < 0.01), while COD and nitrite varied significantly with season (P < 0.05). Although, the treated effluent fell within recommended water quality standard for pH, TDS, nitrate and nitrite, it fell short of stipulated standards for other parameters. Whereas the microbial quality of the secondary treated effluent at this (urban) facility fell short of recommended standard after secondary treatment, its physicochemical quality were generally compliant with recommended standards for reuse wastewater in agriculture and aquaculture. Listeria pathogens isolated from effluents of the rural wastewater facility were sensitive to 11 (55 percent) of the 20 test antibiotics, and showed varying (7-71 percent) levels of resistance to 8 antibiotics; whereas those isolated from the peri-urban community showed sensitivity to 6 (30 percent) of the 20 test antibiotics, and varying (6-94 percent) levels of resistance to 12 antibiotics; while the urban effluent isolates were sensitive to 3 (15 percent) of the 20 test antibiotics, and showed varying (4.5-91 percent) levels of resistance to 17 antibiotics. Multiple antibiotic resistances involving 78.5-100 percent of isolates and antibiotics combination ranging from 2-10 antibiotics was observed across the sampled locations. Penicillin G and ampicillin showed remarkably high (64-91 percent) phenotypic resistance across the three sampled facilities. Other antibiotics, to which isolates showed significant resistance, were linezolid (22-88 percent); erythromycin (43-94 percent) and sulphamethoxazole (7-94 percent). Two of the 14 Listeria strains isolated from the rural effluents were positive for ereA and sul1 antibiotic resistance genes; while sulII genes were detected in five of the 23 Listeria isolates from the urban effluent and none was detected in isolates from the peri-urban community. The presence of antimicrobial resistance genes in the isolates did not correlate with phenotypic antibiotic resistance. The current study demonstrated that Listeria pathogens easily survived the activated sludge treatment process as free-living and plankton attached entities and suggests that municipal wastewater treatment plants are a significant source of multiple resistant Listeria pathogens in the South African aquatic milieu. While the physicochemical quality of the urban final effluent suggests that it is a major source of pollution to the receiving watershed, the secondary effluent quality demonstrated a great potential for use in agriculture and aquaculture.
- Full Text:
- Date Issued: 2010
Prevalence of Listeria pathogens in effluents of some wastewater treatment facilities in the Eastern Cape Province of South Africa
- Odjadjare, Emmanuel Erufuare Onogwuwhenya
- Authors: Odjadjare, Emmanuel Erufuare Onogwuwhenya
- Date: 2010
- Subjects: Listeria -- South Africa -- Eastern Cape Sewage -- Purification -- South Africa -- Eastern Cape Water -- Pollution -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/7826 , vital:30747
- Description: astewater discharges may contain health compromising pathogens and carcinogenic and/or chemical substances that could compromise the public health and impact negatively on the environment. The present study was conducted between August 2007 and July 2008 to evaluate the Listeria abundance (as free-living and plankton associated species) and physicochemical qualities of the final effluents of three wastewater treatment facilities in the Eastern Cape Province of South Africa selected to represent typical urban, peri-urban and rural communities and the impact of the discharged final effluents on their respective receiving watershed, as well as to elucidated the in vitro antibiotic susceptibilities and resistance genes profile of Listeria species isolated from the final effluents. The suitability of the secondary effluent of the urban treatment facility (as a case study) for use in agriculture and aquaculture with reference to recommended standards was also determined. Wastewater samples were collected from the raw sewage, secondary effluent, final treated effluent, discharge point, 500 m upstream discharge point, and 500 m downstream discharge point from all three locations on a monthly basis throughout the study period. Listeria abundance in the final effluents and the receiving watersheds varied between 2.9× 100 and 3.52 × 105cfu/ml across the sampled locations. Free-living listerial density across the sampled locations ranged between 0 and 3.2 × 103cfu/ml while counts of Listeria species attached to large (180 μm) planktons varied from 0 to 1.58 × 105 cfu/ml and those of the 60 and 20 μm categories were in the range of 0 to 1.32 × 103 cfu/ml and 0 to 2.82 × 105 cfu/ml respectively. Listeria abundance did not vary significantly with location and season; there was however, significant (P < 0.05; P < 0.01) variance in Listeria abundance with plankton sizes across the locations. Free-living Listeria species were more abundant in the rural and urban xii communities than plankton attached Listeria species; whereas the reverse was the case in the peri-urban community.
- Full Text:
- Date Issued: 2010
- Authors: Odjadjare, Emmanuel Erufuare Onogwuwhenya
- Date: 2010
- Subjects: Listeria -- South Africa -- Eastern Cape Sewage -- Purification -- South Africa -- Eastern Cape Water -- Pollution -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/7826 , vital:30747
- Description: astewater discharges may contain health compromising pathogens and carcinogenic and/or chemical substances that could compromise the public health and impact negatively on the environment. The present study was conducted between August 2007 and July 2008 to evaluate the Listeria abundance (as free-living and plankton associated species) and physicochemical qualities of the final effluents of three wastewater treatment facilities in the Eastern Cape Province of South Africa selected to represent typical urban, peri-urban and rural communities and the impact of the discharged final effluents on their respective receiving watershed, as well as to elucidated the in vitro antibiotic susceptibilities and resistance genes profile of Listeria species isolated from the final effluents. The suitability of the secondary effluent of the urban treatment facility (as a case study) for use in agriculture and aquaculture with reference to recommended standards was also determined. Wastewater samples were collected from the raw sewage, secondary effluent, final treated effluent, discharge point, 500 m upstream discharge point, and 500 m downstream discharge point from all three locations on a monthly basis throughout the study period. Listeria abundance in the final effluents and the receiving watersheds varied between 2.9× 100 and 3.52 × 105cfu/ml across the sampled locations. Free-living listerial density across the sampled locations ranged between 0 and 3.2 × 103cfu/ml while counts of Listeria species attached to large (180 μm) planktons varied from 0 to 1.58 × 105 cfu/ml and those of the 60 and 20 μm categories were in the range of 0 to 1.32 × 103 cfu/ml and 0 to 2.82 × 105 cfu/ml respectively. Listeria abundance did not vary significantly with location and season; there was however, significant (P < 0.05; P < 0.01) variance in Listeria abundance with plankton sizes across the locations. Free-living Listeria species were more abundant in the rural and urban xii communities than plankton attached Listeria species; whereas the reverse was the case in the peri-urban community.
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- Date Issued: 2010