A P2P middleware design for digital access nodes in marginalised rural areas
- Authors: Wertlen, Ronald
- Date: 2010
- Subjects: Software design , Rural development -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Sustainable development -- Simulation methods , Computer networks , Data transmission systems , Electronic data processing -- Distributed processing , Middleware -- Development , Computer software
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11391 , http://hdl.handle.net/10353/254 , Software design , Rural development -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Sustainable development -- Simulation methods , Computer networks , Data transmission systems , Electronic data processing -- Distributed processing , Middleware -- Development , Computer software
- Description: This thesis addresses software design within the field of Information and Communications Technology for Development (ICTD). Specifically, it makes a case for the design and development of software which is custom-made for the context of marginalised rural areas (MRAs). One of the main aims of any ICTD project is sustainability and such sustainability is particularly difficult in MRAs because of the high costs of projects located there. Most literature on ICTD projects focuses on other factors, such as management, regulations, social and community issues when discussing this issue. Technical matters are often down-played or ignored entirely. This thesis argues that MRAs exhibit unique technical characteristics and that by understanding these characteristics, one can possibly design more cost-effective software. One specific characteristic is described and addressed in this thesis – a characteristic we describe here for the first time and call a network island. Further analysis of the literature generates a picture of a distributed network of access nodes (DANs) within such network islands, which are connected by high speed networks and are able to share resources and stimulate usage of technology by offering a wide range of services. This thesis attempts to design a fitting middleware platform for such a context, which would achieve the following aims: i) allow software developers to create solutions for the context more efficiently (correctly, rapidly); ii) stimulate product managers and business owners to create innovative software products more easily (cost-effectively). A given in the context of this thesis is that the software should use free/libre open source software (FLOSS) – good arguments do also exist for the use of FLOSS. A review of useful FLOSS frameworks is undertaken and several of these are examined in an applied part of the thesis, to see how useful they may be. They form the basis for a walking skeleton implementation of the proposed middleware. The Spring framework is the basis for experiments, along with Spring-Webservices, JMX and PHP 5’s web service capabilities. This thesis builds on three years of work at the Siyakhula Living Lab (SLL), an experimental testbed in a MRA in the Mbashe district of the Eastern Cape of South Africa. Several existing products are deployed at the SLL in the fields of eCommerce, eGovernment and eLearning. Requirements specifications are engineered from a variety of sources, including interviews, mailing lists, the author’s experience as a supervisor at the SLL, and a review of the existing SLL products. Future products are also investigated, as the thesis considers current trends in ICTD. Use cases are also derived and listed. Most of the use cases are concerned with management functions of DANs that can be automated, so that operators of DANs can focus on their core business and not on technology. Using the UML Components methodology, the thesis then proceeds to design a middleware component architecture that is derived from the requirements specification. The process proceeds step-by-step, so that the reader can follow how business rules, operations and interfaces are derived from the use cases. Ultimately, the business rules, interfaces and operations are related to business logic, system interfaces and operations that are situated in specific components. The components in turn are derived from the business information model, that is derived from the business concepts that were initially used to describe the context for the requirements engineering. In this way, a logical method for software design is applied to the problem domain to methodically derive a software design for a middleware solution. The thesis tests the design by considering possible weaknesses in the design. The network aspect is tested by interpolating from formal assumptions about the nature of the context. The data access layer is also identified as a possible bottleneck. We suggest the use of fast indexing methods instead of relational databases to maintain flexibility and efficiency of the data layer. Lessons learned from the exercise are discussed, within the context of the author’s experience in software development teams, as well as in ICTD projects. This synthesis of information leads to warnings about the psychology of middleware development. We note that the ICTD domain is a particularly difficult one with regards to software development as business requirements are not usually clearly formulated and developers do not have the requisite domain knowledge. In conclusion, the core arguments of the thesis are recounted in a bullet form, to lay bare the reasoning behind this work. Novel aspects of the work are also highlighted. They include the description of a network island, and aspects of the DAN middleware requirements engineering and design. Future steps for work based on this thesis are mapped out and open problems relating to this research are touched upon.
- Full Text:
- Date Issued: 2010
- Authors: Wertlen, Ronald
- Date: 2010
- Subjects: Software design , Rural development -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Sustainable development -- Simulation methods , Computer networks , Data transmission systems , Electronic data processing -- Distributed processing , Middleware -- Development , Computer software
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11391 , http://hdl.handle.net/10353/254 , Software design , Rural development -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Sustainable development -- Simulation methods , Computer networks , Data transmission systems , Electronic data processing -- Distributed processing , Middleware -- Development , Computer software
- Description: This thesis addresses software design within the field of Information and Communications Technology for Development (ICTD). Specifically, it makes a case for the design and development of software which is custom-made for the context of marginalised rural areas (MRAs). One of the main aims of any ICTD project is sustainability and such sustainability is particularly difficult in MRAs because of the high costs of projects located there. Most literature on ICTD projects focuses on other factors, such as management, regulations, social and community issues when discussing this issue. Technical matters are often down-played or ignored entirely. This thesis argues that MRAs exhibit unique technical characteristics and that by understanding these characteristics, one can possibly design more cost-effective software. One specific characteristic is described and addressed in this thesis – a characteristic we describe here for the first time and call a network island. Further analysis of the literature generates a picture of a distributed network of access nodes (DANs) within such network islands, which are connected by high speed networks and are able to share resources and stimulate usage of technology by offering a wide range of services. This thesis attempts to design a fitting middleware platform for such a context, which would achieve the following aims: i) allow software developers to create solutions for the context more efficiently (correctly, rapidly); ii) stimulate product managers and business owners to create innovative software products more easily (cost-effectively). A given in the context of this thesis is that the software should use free/libre open source software (FLOSS) – good arguments do also exist for the use of FLOSS. A review of useful FLOSS frameworks is undertaken and several of these are examined in an applied part of the thesis, to see how useful they may be. They form the basis for a walking skeleton implementation of the proposed middleware. The Spring framework is the basis for experiments, along with Spring-Webservices, JMX and PHP 5’s web service capabilities. This thesis builds on three years of work at the Siyakhula Living Lab (SLL), an experimental testbed in a MRA in the Mbashe district of the Eastern Cape of South Africa. Several existing products are deployed at the SLL in the fields of eCommerce, eGovernment and eLearning. Requirements specifications are engineered from a variety of sources, including interviews, mailing lists, the author’s experience as a supervisor at the SLL, and a review of the existing SLL products. Future products are also investigated, as the thesis considers current trends in ICTD. Use cases are also derived and listed. Most of the use cases are concerned with management functions of DANs that can be automated, so that operators of DANs can focus on their core business and not on technology. Using the UML Components methodology, the thesis then proceeds to design a middleware component architecture that is derived from the requirements specification. The process proceeds step-by-step, so that the reader can follow how business rules, operations and interfaces are derived from the use cases. Ultimately, the business rules, interfaces and operations are related to business logic, system interfaces and operations that are situated in specific components. The components in turn are derived from the business information model, that is derived from the business concepts that were initially used to describe the context for the requirements engineering. In this way, a logical method for software design is applied to the problem domain to methodically derive a software design for a middleware solution. The thesis tests the design by considering possible weaknesses in the design. The network aspect is tested by interpolating from formal assumptions about the nature of the context. The data access layer is also identified as a possible bottleneck. We suggest the use of fast indexing methods instead of relational databases to maintain flexibility and efficiency of the data layer. Lessons learned from the exercise are discussed, within the context of the author’s experience in software development teams, as well as in ICTD projects. This synthesis of information leads to warnings about the psychology of middleware development. We note that the ICTD domain is a particularly difficult one with regards to software development as business requirements are not usually clearly formulated and developers do not have the requisite domain knowledge. In conclusion, the core arguments of the thesis are recounted in a bullet form, to lay bare the reasoning behind this work. Novel aspects of the work are also highlighted. They include the description of a network island, and aspects of the DAN middleware requirements engineering and design. Future steps for work based on this thesis are mapped out and open problems relating to this research are touched upon.
- Full Text:
- Date Issued: 2010
Agricultural mechanization for sustainable agriculture and food security in Zimbabwe: a case of Bindura District in Mashonaland Central Province
- Authors: Chisango, Future, T
- Date: 2010
- Subjects: Farm mechanization -- Zimbabwe , Agricultural machinery -- Zimbabwe , Agricultural productivity -- Zimbabwe , Sustainable agriculture -- Zimbabwe , Food supply -- Zimbabwe , Agriculture and state -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11156 , http://hdl.handle.net/10353/348 , Farm mechanization -- Zimbabwe , Agricultural machinery -- Zimbabwe , Agricultural productivity -- Zimbabwe , Sustainable agriculture -- Zimbabwe , Food supply -- Zimbabwe , Agriculture and state -- Zimbabwe
- Description: A cardinal development goal of the Zimbabwean government is agricultural mechanization through the acquisition and use of tractors by arable crop farmers in communal and resettlement state land. This research project therefore aimed at investigating the impact of mechanization on agricultural productivity focusing on farmers in Bindura district of Zimbabwe who benefitted under the ongoing farm mechanization program. The existing land policy and the issue of technical efficiency in agricultural productivity are assumed to be the drivers of the program. It is likely that these key issues will constitute an important consideration in determining the sustainability of the mechanization policy. A multistage sampling technique was used to randomly select 90 farmers in the study area. The Cobb Douglas approach and Logistic regression were used to analyze data obtained from the respondents. Results revealed that tractor use was positively influenced by household size, access to extension services and crop output equivalent. Education, land area cultivated, stoniness negatively influenced the probability of adoption of mechanized farming. Furthermore, the technical efficiency estimate of adopter and nonadopters of mechanized farming showed no difference in their level of technical efficiency in agricultural productivity that was 64 percent on average. The level of observed inefficiency was increased by slope, stoniness and household size while age reduced technical inefficiency. It is recommended that government should consolidate the present gains arising from extension services. Also, environmental factors such as slope (topography) and stoniness, which constituted major disincentives in communal areas, could be overcome if government and farmers can identify and open up new areas of farmland for occupation by farmers.
- Full Text:
- Date Issued: 2010
- Authors: Chisango, Future, T
- Date: 2010
- Subjects: Farm mechanization -- Zimbabwe , Agricultural machinery -- Zimbabwe , Agricultural productivity -- Zimbabwe , Sustainable agriculture -- Zimbabwe , Food supply -- Zimbabwe , Agriculture and state -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11156 , http://hdl.handle.net/10353/348 , Farm mechanization -- Zimbabwe , Agricultural machinery -- Zimbabwe , Agricultural productivity -- Zimbabwe , Sustainable agriculture -- Zimbabwe , Food supply -- Zimbabwe , Agriculture and state -- Zimbabwe
- Description: A cardinal development goal of the Zimbabwean government is agricultural mechanization through the acquisition and use of tractors by arable crop farmers in communal and resettlement state land. This research project therefore aimed at investigating the impact of mechanization on agricultural productivity focusing on farmers in Bindura district of Zimbabwe who benefitted under the ongoing farm mechanization program. The existing land policy and the issue of technical efficiency in agricultural productivity are assumed to be the drivers of the program. It is likely that these key issues will constitute an important consideration in determining the sustainability of the mechanization policy. A multistage sampling technique was used to randomly select 90 farmers in the study area. The Cobb Douglas approach and Logistic regression were used to analyze data obtained from the respondents. Results revealed that tractor use was positively influenced by household size, access to extension services and crop output equivalent. Education, land area cultivated, stoniness negatively influenced the probability of adoption of mechanized farming. Furthermore, the technical efficiency estimate of adopter and nonadopters of mechanized farming showed no difference in their level of technical efficiency in agricultural productivity that was 64 percent on average. The level of observed inefficiency was increased by slope, stoniness and household size while age reduced technical inefficiency. It is recommended that government should consolidate the present gains arising from extension services. Also, environmental factors such as slope (topography) and stoniness, which constituted major disincentives in communal areas, could be overcome if government and farmers can identify and open up new areas of farmland for occupation by farmers.
- Full Text:
- Date Issued: 2010
An analysis of groundwater in Mjinchi District of Central Malawi
- Authors: Mleta, Prince W C
- Date: 2010
- Subjects: Groundwater -- Malawi , Water-supply -- Malawi
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11510 , http://hdl.handle.net/10353/366 , Groundwater -- Malawi , Water-supply -- Malawi
- Description: Groundwater resources is the major source of potable water in Mchinji District of Central Malawi and globally. Although the total amount of water on and under the earth‟s surface is generally assumed to have remained constant, the rapid population boom coupled with extension of agricultural farmland and industrial development are putting pressure and stress on the quality and quantity of water resources. In principal therefore, „use and discard‟ philosophy in water resources cannot be subscribed (Lloyd, 1999). The situation ultimately calls for rational management of water resources to ensure its sustainability. Water intended for human consumption must be free from organisms that are the causative agents of diseases and must not contain chemical substances at concentrations that may be hazardous to human health. In addition drinking water should be aesthetically acceptable, free from unpleasant taste, color, odor and turbidity. Drinking water should also be free from bacteria and viruses whose presence would indicate fecal contamination. Some are known to be toxic and their concentrations must be below acceptable value, taking into account that drinking water is but one of the several pathways by which substances enters the body. ix Due to perceived concerns of over extraction and rapid water resources depletion, optimal management of groundwater resources are now receiving much attention. Their associated literatures have taken quite different approaches both philosophically and operationally to the analysis of how groundwater should be managed, allocated and cared for spatially and temporally. This study investigated the spatial and temporal fluctuations of concentrations of chemical and biological substances in groundwater such as pH, electrical conductivity, total dissolved solids, iron, fluoride, manganese, chloride, sulfates, sodium and fecal coliform in Mchinji District of Central Malawi. Through examination and analysis of static water levels as an indicator of water table fluctuations, groundwater availability was also measured. It was found that anthropogenic activities on the landscape can impact the quality and quantity of the water resources in this area and this impact on the various sectors of the inhabitant‟s livelihoods. Groundwater in Mchinji is composed of a number of chemical and biological elements whose origin is either from the material in which it percolates through, or stored before exploitation. Anthropogenic activities in this area plays a role in the quality and quantity of groundwater through land use and land cover change as evidenced by comparisons of Landsat Thematic x Mapper™ satellite images over different time scales. In Mchinji no regular groundwater monitoring is being done indicating a deficiency in sustainability interventions of the resource. This study calls for integrated and sustainable water resources management and coordinated efforts amongst water users, local councils, regulatory authorities and environmental policy makers. Of far greater importance in groundwater sustainability analysis is the issue of groundwater monitoring. It is imperative therefore to preserve the resource while preservation is still possible. Groundwater is now turning into „blue gold‟ and becoming a highly sought-after commodity. It should, however, be utilized sustainably to meet the needs of the present without compromising the ability of future generations to meet their own needs.
- Full Text:
- Date Issued: 2010
- Authors: Mleta, Prince W C
- Date: 2010
- Subjects: Groundwater -- Malawi , Water-supply -- Malawi
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11510 , http://hdl.handle.net/10353/366 , Groundwater -- Malawi , Water-supply -- Malawi
- Description: Groundwater resources is the major source of potable water in Mchinji District of Central Malawi and globally. Although the total amount of water on and under the earth‟s surface is generally assumed to have remained constant, the rapid population boom coupled with extension of agricultural farmland and industrial development are putting pressure and stress on the quality and quantity of water resources. In principal therefore, „use and discard‟ philosophy in water resources cannot be subscribed (Lloyd, 1999). The situation ultimately calls for rational management of water resources to ensure its sustainability. Water intended for human consumption must be free from organisms that are the causative agents of diseases and must not contain chemical substances at concentrations that may be hazardous to human health. In addition drinking water should be aesthetically acceptable, free from unpleasant taste, color, odor and turbidity. Drinking water should also be free from bacteria and viruses whose presence would indicate fecal contamination. Some are known to be toxic and their concentrations must be below acceptable value, taking into account that drinking water is but one of the several pathways by which substances enters the body. ix Due to perceived concerns of over extraction and rapid water resources depletion, optimal management of groundwater resources are now receiving much attention. Their associated literatures have taken quite different approaches both philosophically and operationally to the analysis of how groundwater should be managed, allocated and cared for spatially and temporally. This study investigated the spatial and temporal fluctuations of concentrations of chemical and biological substances in groundwater such as pH, electrical conductivity, total dissolved solids, iron, fluoride, manganese, chloride, sulfates, sodium and fecal coliform in Mchinji District of Central Malawi. Through examination and analysis of static water levels as an indicator of water table fluctuations, groundwater availability was also measured. It was found that anthropogenic activities on the landscape can impact the quality and quantity of the water resources in this area and this impact on the various sectors of the inhabitant‟s livelihoods. Groundwater in Mchinji is composed of a number of chemical and biological elements whose origin is either from the material in which it percolates through, or stored before exploitation. Anthropogenic activities in this area plays a role in the quality and quantity of groundwater through land use and land cover change as evidenced by comparisons of Landsat Thematic x Mapper™ satellite images over different time scales. In Mchinji no regular groundwater monitoring is being done indicating a deficiency in sustainability interventions of the resource. This study calls for integrated and sustainable water resources management and coordinated efforts amongst water users, local councils, regulatory authorities and environmental policy makers. Of far greater importance in groundwater sustainability analysis is the issue of groundwater monitoring. It is imperative therefore to preserve the resource while preservation is still possible. Groundwater is now turning into „blue gold‟ and becoming a highly sought-after commodity. It should, however, be utilized sustainably to meet the needs of the present without compromising the ability of future generations to meet their own needs.
- Full Text:
- Date Issued: 2010
Application of the sustainable livelihoods framework to the analysis of the Provincial Growth and Development Plan of the Eastern Cape: a case study of the Massive Food Production Programme in Nkonkobe Municipality and Buffalo City Municipality
- Authors: Dirwayi, Tafadzwa P
- Date: 2010
- Subjects: Sustainable agriculture -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Rural poor -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Food security -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11159 , http://hdl.handle.net/10353/353 , Sustainable agriculture -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Rural poor -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Food security -- South Africa -- Eastern Cape
- Description: The Government of the Eastern Cape Province introduced the Massive Food Production programme, which is a cornerstone within the agrarian reform initiative of the Provincial Growth and Development Plan (PGDP). The programme has been going on for more than seven years, however little has been documented on its impact. The main objective of the study was to investigate the impact of the Massive Food Production Programme on the livelihoods in Nkonkobe Municipality. This study did not only investigate its impact on the participants but also assessed its impact on the recipient communities. Accordingly, the specific objectives of the study were to investigate the impact of the Massive Food Programme on the asset base of participants, the general livelihood activities, and the livelihood outcomes. Among other livelihood activities, the study made an in-depth investigation on the impact of the Massive Food Production Programme on maize crop production. This is because the Massive Food Production was aimed at maize crop production. Previous studies investigated on the indicators of success that can be used to measure the impact of this programme. After the wide-ranging evaluation of views, arguments and research findings, a model to measure impact of the programme was designed. The asset base improvement was used as the proxy of impact. Nine factors were selected from the principal component analysis of the many factors that were taken to affect participation. Three other dummy variables to proximate location, participation and group turnover were added to the regression model that was developed to measure impact. The DFID Sustainable Livelihood Framework was used to investigate the impact of the Massive Food Production Programme. This approach was used in both conceptualizing the study and the selection of variables. The DFID Sustainable Livelihood Approach was selected because unlike the CARE or UNDP Sustainable Livelihood models, it was designed for such purposes. Data collection was accomplished through observation, interviewing, and focus group discussions. The researcher also made use of project annual reports on change of livelihoods, baseline survey reports, project log frame, internal reports, work plans, budgets and mid-term evaluation reports as sources of secondary data. v The research findings were analysed using several analytical procedures, including the conventional descriptive statistics, principal components analysis, and linear regression analysis. The use of the different types of analysis was driven by the research questions under investigation and the theories on which they are based, and by the available data. The study revealed that to some extent the Massive Food Production Programme has managed to improve the asset base of the farmers. However, its impact on ensuring food security is still debatable. Findings of the study revealed that most of the participants and the non-participants communities experienced food shortages in the last season 2007/8 for at most three months. The study revealed that the highest agricultural income is from livestock sales. The varying locations showed the potential of livestock production. It is recommended that development agencies consider livestock production as an agricultural strategy with immense potential for enhancing sustaining rural livelihoods
- Full Text:
- Date Issued: 2010
- Authors: Dirwayi, Tafadzwa P
- Date: 2010
- Subjects: Sustainable agriculture -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Rural poor -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Food security -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11159 , http://hdl.handle.net/10353/353 , Sustainable agriculture -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Rural poor -- South Africa -- Eastern Cape , Food supply -- South Africa -- Eastern Cape , Food security -- South Africa -- Eastern Cape
- Description: The Government of the Eastern Cape Province introduced the Massive Food Production programme, which is a cornerstone within the agrarian reform initiative of the Provincial Growth and Development Plan (PGDP). The programme has been going on for more than seven years, however little has been documented on its impact. The main objective of the study was to investigate the impact of the Massive Food Production Programme on the livelihoods in Nkonkobe Municipality. This study did not only investigate its impact on the participants but also assessed its impact on the recipient communities. Accordingly, the specific objectives of the study were to investigate the impact of the Massive Food Programme on the asset base of participants, the general livelihood activities, and the livelihood outcomes. Among other livelihood activities, the study made an in-depth investigation on the impact of the Massive Food Production Programme on maize crop production. This is because the Massive Food Production was aimed at maize crop production. Previous studies investigated on the indicators of success that can be used to measure the impact of this programme. After the wide-ranging evaluation of views, arguments and research findings, a model to measure impact of the programme was designed. The asset base improvement was used as the proxy of impact. Nine factors were selected from the principal component analysis of the many factors that were taken to affect participation. Three other dummy variables to proximate location, participation and group turnover were added to the regression model that was developed to measure impact. The DFID Sustainable Livelihood Framework was used to investigate the impact of the Massive Food Production Programme. This approach was used in both conceptualizing the study and the selection of variables. The DFID Sustainable Livelihood Approach was selected because unlike the CARE or UNDP Sustainable Livelihood models, it was designed for such purposes. Data collection was accomplished through observation, interviewing, and focus group discussions. The researcher also made use of project annual reports on change of livelihoods, baseline survey reports, project log frame, internal reports, work plans, budgets and mid-term evaluation reports as sources of secondary data. v The research findings were analysed using several analytical procedures, including the conventional descriptive statistics, principal components analysis, and linear regression analysis. The use of the different types of analysis was driven by the research questions under investigation and the theories on which they are based, and by the available data. The study revealed that to some extent the Massive Food Production Programme has managed to improve the asset base of the farmers. However, its impact on ensuring food security is still debatable. Findings of the study revealed that most of the participants and the non-participants communities experienced food shortages in the last season 2007/8 for at most three months. The study revealed that the highest agricultural income is from livestock sales. The varying locations showed the potential of livestock production. It is recommended that development agencies consider livestock production as an agricultural strategy with immense potential for enhancing sustaining rural livelihoods
- Full Text:
- Date Issued: 2010
Assessment of antibiotic production by some marine Streptomyces isolated from the Nahoon Beach
- Ogunmwonyi, Isoken Nekpen Henrietta
- Authors: Ogunmwonyi, Isoken Nekpen Henrietta
- Date: 2010
- Subjects: Streptomyces , Actinobacteria , Gram-positive bacteria , Antibiotics , Antibiotics -- Testing , Drug resistance in microorganisms
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11243 , http://hdl.handle.net/10353/264 , Streptomyces , Actinobacteria , Gram-positive bacteria , Antibiotics , Antibiotics -- Testing , Drug resistance in microorganisms
- Description: Rapidly emerging strains of bacteria resistant to most advanced antibiotics have become issues of very important public health concern. Research currently directed towards marine actinomycetes presents a vast potential for new compounds that could be able to safely and effectively target resistant species. In this regard, ten putative Streptomyces strains isolated from the Nahoon beach were selected and assessed for antibiotic production and activity against a wide range of bacteria including reference strains, environmental strain and clinical isolates. The ethyl acetate extracts of the putative Streptomyces isolates showed activities against at least 6 and up to 26 of the 32 test bacteria. Inhibition zones were found to range between 9-32 mm diameters at a concentration of 10 mg/ml. The minimum inhibitory concentrations (MICs) of the crude extracts ranged from 0.039 - 10 mg/ml and the least minimum bactericidal concentration (MBC) demonstrated was 0.625 mg/ml against a reference strain Staphylococcus aureus ATCC 6538. Time kill kinetics of all extracts revealed bacteristatic and bactericidal activities. Average Log reductions in viable cell counts for all the extracts ranged from 0.86 Log10 and 3.99 Log10 cfu/ml after 3 h interaction and 0.01 Log10 and 4.86 Log10 after 6 h interaction at MIC, 2 × MIC, 3 × MIC and 4 × MIC concentrations. Most of the extracts were speedily bactericidal at 3 × MIC and 4 × MIC resulting in over 50 % elimination of most of the test bacteria within 3 h and 6 h interaction. The partial characterization of the crude extracts by IR spectral analysis revealed possibility of terpenoid, long chain fatty acids and secondary amine derivatives compounds in the extracts. It is therefore recommended that further investigation should address the relationship between the structure of the active component of the extracts and the broad spectrum activity, as well as a rapid method for large scale production and purification and whether this group of antibiotics has any application in managing human infectious disease.
- Full Text:
- Date Issued: 2010
- Authors: Ogunmwonyi, Isoken Nekpen Henrietta
- Date: 2010
- Subjects: Streptomyces , Actinobacteria , Gram-positive bacteria , Antibiotics , Antibiotics -- Testing , Drug resistance in microorganisms
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11243 , http://hdl.handle.net/10353/264 , Streptomyces , Actinobacteria , Gram-positive bacteria , Antibiotics , Antibiotics -- Testing , Drug resistance in microorganisms
- Description: Rapidly emerging strains of bacteria resistant to most advanced antibiotics have become issues of very important public health concern. Research currently directed towards marine actinomycetes presents a vast potential for new compounds that could be able to safely and effectively target resistant species. In this regard, ten putative Streptomyces strains isolated from the Nahoon beach were selected and assessed for antibiotic production and activity against a wide range of bacteria including reference strains, environmental strain and clinical isolates. The ethyl acetate extracts of the putative Streptomyces isolates showed activities against at least 6 and up to 26 of the 32 test bacteria. Inhibition zones were found to range between 9-32 mm diameters at a concentration of 10 mg/ml. The minimum inhibitory concentrations (MICs) of the crude extracts ranged from 0.039 - 10 mg/ml and the least minimum bactericidal concentration (MBC) demonstrated was 0.625 mg/ml against a reference strain Staphylococcus aureus ATCC 6538. Time kill kinetics of all extracts revealed bacteristatic and bactericidal activities. Average Log reductions in viable cell counts for all the extracts ranged from 0.86 Log10 and 3.99 Log10 cfu/ml after 3 h interaction and 0.01 Log10 and 4.86 Log10 after 6 h interaction at MIC, 2 × MIC, 3 × MIC and 4 × MIC concentrations. Most of the extracts were speedily bactericidal at 3 × MIC and 4 × MIC resulting in over 50 % elimination of most of the test bacteria within 3 h and 6 h interaction. The partial characterization of the crude extracts by IR spectral analysis revealed possibility of terpenoid, long chain fatty acids and secondary amine derivatives compounds in the extracts. It is therefore recommended that further investigation should address the relationship between the structure of the active component of the extracts and the broad spectrum activity, as well as a rapid method for large scale production and purification and whether this group of antibiotics has any application in managing human infectious disease.
- Full Text:
- Date Issued: 2010
Assessment of bioflocculant production by some marine bacteria isolated from the bottom sediment of Algoa Bay
- Authors: Cosa, Sekelwa
- Date: 2010
- Subjects: Flocculants , Bacteria -- South Africa -- Algoa Bay
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11244 , http://hdl.handle.net/10353/404 , Flocculants , Bacteria -- South Africa -- Algoa Bay
- Description: Several problems concerning the use of conventional synthetic flocculants has necessitated the need for alternative cost effective, safe and efficient bioflocculants from microorganisms inhabiting many environments, particularly those from unusual environments. Hence, this study assessed bioflocculant production by three marine bacteria isolated from the bottom sediment of Algoa Bay in the Eastern Cape Province of South Africa. Analysis of the 16S rDNA sequences led to their identification as Halobacillus sp. Mvuyo, Virgibacillus sp. Rob and Oceanobacillus sp. Pinky. Several factors affecting the production and activity of the bioflocculant(s) were studied. Halobacillus sp. Mvuyo produced bioflocculant optimally with glucose (76%) and ammonium chloride (93%) as sole carbon and nitrogen sources, respectively and at neutral pH and in the presence of Ca2+. On the other hand, Virgibacillus sp. Rob preferred glucose (70.4 %) and iron sulphate (74%) as carbon and nitrogen source respectively; an alkaline pH (12.0) and Fe2+. Oceanobacillus sp. Pinky produced bioflocculant optimally when sucrose (80%) and peptone (72.4 %) were used as carbon and nitrogen source respectively, at neutral pH, and in the presence of Ca2+ cation. The chemical analyses of the partially purified bioflocculants revealed that the bioflocculants produced by Halobacillus sp. Mvuyo and Oceanobacillus sp. Pinky were glycoproteins, while that produced by Virgibacillus sp. Rob was a polysaccharide. We thus conclude that Halobacillus sp. Mvuyo, Virgibacillus sp. Rob and Oceanobacillus sp. Pinky hold promise as producers of new and efficient bioflocculant(s). We recommended development of process conditions for large scale production of the bioflocculants followed by their detailed characterization, as well as pilot scale assessment of the applicability of the purified bioflocculant in water/wastewater treatment and other industrial uses
- Full Text:
- Date Issued: 2010
- Authors: Cosa, Sekelwa
- Date: 2010
- Subjects: Flocculants , Bacteria -- South Africa -- Algoa Bay
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11244 , http://hdl.handle.net/10353/404 , Flocculants , Bacteria -- South Africa -- Algoa Bay
- Description: Several problems concerning the use of conventional synthetic flocculants has necessitated the need for alternative cost effective, safe and efficient bioflocculants from microorganisms inhabiting many environments, particularly those from unusual environments. Hence, this study assessed bioflocculant production by three marine bacteria isolated from the bottom sediment of Algoa Bay in the Eastern Cape Province of South Africa. Analysis of the 16S rDNA sequences led to their identification as Halobacillus sp. Mvuyo, Virgibacillus sp. Rob and Oceanobacillus sp. Pinky. Several factors affecting the production and activity of the bioflocculant(s) were studied. Halobacillus sp. Mvuyo produced bioflocculant optimally with glucose (76%) and ammonium chloride (93%) as sole carbon and nitrogen sources, respectively and at neutral pH and in the presence of Ca2+. On the other hand, Virgibacillus sp. Rob preferred glucose (70.4 %) and iron sulphate (74%) as carbon and nitrogen source respectively; an alkaline pH (12.0) and Fe2+. Oceanobacillus sp. Pinky produced bioflocculant optimally when sucrose (80%) and peptone (72.4 %) were used as carbon and nitrogen source respectively, at neutral pH, and in the presence of Ca2+ cation. The chemical analyses of the partially purified bioflocculants revealed that the bioflocculants produced by Halobacillus sp. Mvuyo and Oceanobacillus sp. Pinky were glycoproteins, while that produced by Virgibacillus sp. Rob was a polysaccharide. We thus conclude that Halobacillus sp. Mvuyo, Virgibacillus sp. Rob and Oceanobacillus sp. Pinky hold promise as producers of new and efficient bioflocculant(s). We recommended development of process conditions for large scale production of the bioflocculants followed by their detailed characterization, as well as pilot scale assessment of the applicability of the purified bioflocculant in water/wastewater treatment and other industrial uses
- Full Text:
- Date Issued: 2010
Building a semantic web-based e-health component for a multipurpose communication centre
- Authors: Hlungulu, Bulumko
- Date: 2010
- Subjects: Rural development -- South Africa -- Eastern Cape , Information technology -- South Africa -- Eastern Cape , Internet in medicine -- South Africa -- Eastern Cape , Telecommunication in medicine -- South Africa -- Eastern Cape , Health -- Computer network resources
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11380 , http://hdl.handle.net/10353/374 , Rural development -- South Africa -- Eastern Cape , Information technology -- South Africa -- Eastern Cape , Internet in medicine -- South Africa -- Eastern Cape , Telecommunication in medicine -- South Africa -- Eastern Cape , Health -- Computer network resources
- Description: Rural communities have limited access to health information which is made available on the internet. This is due to poor infrastructure (i.e., lack of clinics or Internet access) and that gives them problems in accessing information within the domain of health. The availability of Information and Communication Technologies (ICTs) in a rural community can provide the community with a number of beneficial solutions to their problems as they maximize the potential of knowledge sharing and delivery. This research seeks to make use of ICTs deployed in the community of Dwesa, in order to contribute to improving the health standards of the community. It seeks to accomplish this by carrying out an investigation and literature review with the aim of understanding health knowledge sharing dynamics in the context of marginalized communities. The knowledge acquired will then be used in the development and implementation of a semantic web-based e-Health portal as part of the Siyakhula Living Lab (SLL) project. This portal will share and deliver western medical knowledge, traditional knowledge and indigenous knowledge. This research seeks to make use of a combination of Free and/or Open Sources Software in developing the portal to make it affordable to the community.
- Full Text:
- Date Issued: 2010
- Authors: Hlungulu, Bulumko
- Date: 2010
- Subjects: Rural development -- South Africa -- Eastern Cape , Information technology -- South Africa -- Eastern Cape , Internet in medicine -- South Africa -- Eastern Cape , Telecommunication in medicine -- South Africa -- Eastern Cape , Health -- Computer network resources
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11380 , http://hdl.handle.net/10353/374 , Rural development -- South Africa -- Eastern Cape , Information technology -- South Africa -- Eastern Cape , Internet in medicine -- South Africa -- Eastern Cape , Telecommunication in medicine -- South Africa -- Eastern Cape , Health -- Computer network resources
- Description: Rural communities have limited access to health information which is made available on the internet. This is due to poor infrastructure (i.e., lack of clinics or Internet access) and that gives them problems in accessing information within the domain of health. The availability of Information and Communication Technologies (ICTs) in a rural community can provide the community with a number of beneficial solutions to their problems as they maximize the potential of knowledge sharing and delivery. This research seeks to make use of ICTs deployed in the community of Dwesa, in order to contribute to improving the health standards of the community. It seeks to accomplish this by carrying out an investigation and literature review with the aim of understanding health knowledge sharing dynamics in the context of marginalized communities. The knowledge acquired will then be used in the development and implementation of a semantic web-based e-Health portal as part of the Siyakhula Living Lab (SLL) project. This portal will share and deliver western medical knowledge, traditional knowledge and indigenous knowledge. This research seeks to make use of a combination of Free and/or Open Sources Software in developing the portal to make it affordable to the community.
- Full Text:
- Date Issued: 2010
Citrus, labour and gender in the Eastern Cape: the case of the Kat River area
- Mzitshi, Zoleka Alice Florence
- Authors: Mzitshi, Zoleka Alice Florence
- Date: 2010
- Subjects: Citrus -- South Africa -- Eastern Cape , Citrus , Working class women -- South Africa -- Eastern Cape , Sex role -- South Africa -- Eastern Cape , Citrus fruit industry -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11511 , http://hdl.handle.net/10353/379 , Citrus -- South Africa -- Eastern Cape , Citrus , Working class women -- South Africa -- Eastern Cape , Sex role -- South Africa -- Eastern Cape , Citrus fruit industry -- South Africa -- Eastern Cape
- Description: Agriculture plays a significant role in South Africa’s export earning and in providing employment opportunities. Amongst the major agricultural crops is citrus. Within the context of postmodern and feminist geographies and utilizing the intensive research design, this thesis discusses citrus production with a focus on growers and black women workers in the Kat River Valley area in Fort Beaufort, Eastern Cape. The thesis also explores the challenges and implications of restructuring within agriculture for growers, cooperatives and labour within the citrus industry. It is argued that whilst legislation related to labour and tenure within agriculture has changed since the mid-1990s, power relations in the citrus industry have remained firmly entrenched. Consequently, the flexible labour strategies that the citrus farmers adopted have had serious consequences for women worker
- Full Text:
- Date Issued: 2010
- Authors: Mzitshi, Zoleka Alice Florence
- Date: 2010
- Subjects: Citrus -- South Africa -- Eastern Cape , Citrus , Working class women -- South Africa -- Eastern Cape , Sex role -- South Africa -- Eastern Cape , Citrus fruit industry -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11511 , http://hdl.handle.net/10353/379 , Citrus -- South Africa -- Eastern Cape , Citrus , Working class women -- South Africa -- Eastern Cape , Sex role -- South Africa -- Eastern Cape , Citrus fruit industry -- South Africa -- Eastern Cape
- Description: Agriculture plays a significant role in South Africa’s export earning and in providing employment opportunities. Amongst the major agricultural crops is citrus. Within the context of postmodern and feminist geographies and utilizing the intensive research design, this thesis discusses citrus production with a focus on growers and black women workers in the Kat River Valley area in Fort Beaufort, Eastern Cape. The thesis also explores the challenges and implications of restructuring within agriculture for growers, cooperatives and labour within the citrus industry. It is argued that whilst legislation related to labour and tenure within agriculture has changed since the mid-1990s, power relations in the citrus industry have remained firmly entrenched. Consequently, the flexible labour strategies that the citrus farmers adopted have had serious consequences for women worker
- Full Text:
- Date Issued: 2010
Developing SOA wrappers for communication purposes in rural areas
- Authors: Samalenge, Jimmy
- Date: 2010
- Subjects: Computer network architectures , Computer architecture , Computer software -- Specifications , Rural development projects -- South Africa -- Eastern Cape , Web services , System design , Technological innovations -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11386 , http://hdl.handle.net/10353/320 , Computer network architectures , Computer architecture , Computer software -- Specifications , Rural development projects -- South Africa -- Eastern Cape , Web services , System design , Technological innovations -- South Africa -- Eastern Cape
- Description: The introduction of Web Services as a platform upon which applications can communicate has contributed a great deal towards the expansion of World Wide Web technologies. The Internet and computing technologies have been some of the factors that have contributed to the socio-economic improvement of urban and industrial areas. This research focuses on the application of Service-Oriented Architecture (SOA) and Web Services technologies in Information and Communication Technologies for Development (ICT4D) contexts. SOA is a style used to design distributed systems, and Web Services are some of the common realizations of the SOA. Web Services allow the exchange of data between two or more machines in a simple and standardized manner over the network. This has resulted in the augmentation of ways in which individuals in a society and in the world communicate. This research aims to develop a SOA-based system with services that are implemented as Web Services. The system is intended to support communication activities of Dwesa community members. The communication methods identified as the most commonly used in the Dwesa community are Short Message Services (SMSs) and voice calls. In this research we have identified further methods (i.e. Multimedia Message Service, Electronic mail and Instant Messaging) to augment communication activities in Dwesa. The developed system, therefore, exposes SMS Web Service, MMS Web Service, Email Web Service and IM Web Service that are consumed in machine-to-machine, machine-to-person and person-to-person types of communication. We have also implemented a one-stop communication shop, through a web portal which provides interfaces to the different communication modules. Elaborate functional and usability testing have also been undertaken to establish the viability and end-user acceptance of the system respectively. This research has provided the initial validation of the effectiveness of the SOA-based system in ICT4D contexts
- Full Text:
- Date Issued: 2010
- Authors: Samalenge, Jimmy
- Date: 2010
- Subjects: Computer network architectures , Computer architecture , Computer software -- Specifications , Rural development projects -- South Africa -- Eastern Cape , Web services , System design , Technological innovations -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11386 , http://hdl.handle.net/10353/320 , Computer network architectures , Computer architecture , Computer software -- Specifications , Rural development projects -- South Africa -- Eastern Cape , Web services , System design , Technological innovations -- South Africa -- Eastern Cape
- Description: The introduction of Web Services as a platform upon which applications can communicate has contributed a great deal towards the expansion of World Wide Web technologies. The Internet and computing technologies have been some of the factors that have contributed to the socio-economic improvement of urban and industrial areas. This research focuses on the application of Service-Oriented Architecture (SOA) and Web Services technologies in Information and Communication Technologies for Development (ICT4D) contexts. SOA is a style used to design distributed systems, and Web Services are some of the common realizations of the SOA. Web Services allow the exchange of data between two or more machines in a simple and standardized manner over the network. This has resulted in the augmentation of ways in which individuals in a society and in the world communicate. This research aims to develop a SOA-based system with services that are implemented as Web Services. The system is intended to support communication activities of Dwesa community members. The communication methods identified as the most commonly used in the Dwesa community are Short Message Services (SMSs) and voice calls. In this research we have identified further methods (i.e. Multimedia Message Service, Electronic mail and Instant Messaging) to augment communication activities in Dwesa. The developed system, therefore, exposes SMS Web Service, MMS Web Service, Email Web Service and IM Web Service that are consumed in machine-to-machine, machine-to-person and person-to-person types of communication. We have also implemented a one-stop communication shop, through a web portal which provides interfaces to the different communication modules. Elaborate functional and usability testing have also been undertaken to establish the viability and end-user acceptance of the system respectively. This research has provided the initial validation of the effectiveness of the SOA-based system in ICT4D contexts
- Full Text:
- Date Issued: 2010
Effects of dietary supplementation on physico-chemical and consumer sensory characteristics of chevon from South African indigenous goat genotypes
- Authors: Xazela, Nomasonto Martha
- Date: 2010
- Subjects: Color of meat , Food -- Sensory evaluation , Commercial products -- Testing , Goats -- South Africa -- Eastern Cape , Goats -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11809 , http://hdl.handle.net/10353/357 , Color of meat , Food -- Sensory evaluation , Commercial products -- Testing , Goats -- South Africa -- Eastern Cape , Goats -- Feeding and feeds
- Description: The study was conducted at the University of Fort Hare farm to assess the effect of dietary supplementation on physico-chemical and consumer sensory characteristics of chevon from South African indigenous goat genotypes. Forty-eight 6-month-old Xhosa lop-eared (XLE), Nguni (NGN), Xhosa-Boer cross (XBC) and Boer (BOR) castrated goats with a body weight range from 20 to 25 kg were used in this study. Half of the goats in each genotype were supplemented with 200g/head/day of sunflower cake. The other half of goats in each genotype was not supplemented. The goats were slaughtered at day 90 to determine slaughter weight (SLW), cold dress mass (CDM), meat colour, cooking loss, meat pH and Warner-Bratzler (WB) shear force values. Furthermore, a consumer sensory evaluation of cooked or fried chevon from supplemented and non-supplemented goats was conducted with consumers of different ages, tribes and gender. The XLE and NGN goats had higher pH24 (P < 0.05) than BOR and XBC goats. Supplemented BOR goats had higher L* values than their non-supplemented counterparts (P < 0.05). The other meat quality attributes in XLE and NGN were comparable to those in meat from the Boer goat. Female respondents gave higher (P < 0.05) sensory scores than male respondents for both cooked and fried meat on aroma intensity. Shona consumers gave higher (P < 0.05) aroma intensity scores than the Xhosa and the Zulu consumers for both cooked and fried meat. In the non-supplemented goats, fried meat for all genotypes was superior (P < 0.05) to the cooked meat for initial impression of juiciness. Age and gender of respondents and thermal iv treatment influenced initial impression of juiciness scores (P < 0.05). The quality of chevon from XLE and NGN was comparable to that of the Boer goat, and dietary supplementation improved most meat quality attributes. Chevon from the supplemented goats had higher consumer sensory scores than chevon from the non-supplemented goats. Keywords: supplementation, meat colour, ultimate pH, consumer sensory evaluation, Xhosa lop eared, Nguni, Boer goats.
- Full Text:
- Date Issued: 2010
- Authors: Xazela, Nomasonto Martha
- Date: 2010
- Subjects: Color of meat , Food -- Sensory evaluation , Commercial products -- Testing , Goats -- South Africa -- Eastern Cape , Goats -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11809 , http://hdl.handle.net/10353/357 , Color of meat , Food -- Sensory evaluation , Commercial products -- Testing , Goats -- South Africa -- Eastern Cape , Goats -- Feeding and feeds
- Description: The study was conducted at the University of Fort Hare farm to assess the effect of dietary supplementation on physico-chemical and consumer sensory characteristics of chevon from South African indigenous goat genotypes. Forty-eight 6-month-old Xhosa lop-eared (XLE), Nguni (NGN), Xhosa-Boer cross (XBC) and Boer (BOR) castrated goats with a body weight range from 20 to 25 kg were used in this study. Half of the goats in each genotype were supplemented with 200g/head/day of sunflower cake. The other half of goats in each genotype was not supplemented. The goats were slaughtered at day 90 to determine slaughter weight (SLW), cold dress mass (CDM), meat colour, cooking loss, meat pH and Warner-Bratzler (WB) shear force values. Furthermore, a consumer sensory evaluation of cooked or fried chevon from supplemented and non-supplemented goats was conducted with consumers of different ages, tribes and gender. The XLE and NGN goats had higher pH24 (P < 0.05) than BOR and XBC goats. Supplemented BOR goats had higher L* values than their non-supplemented counterparts (P < 0.05). The other meat quality attributes in XLE and NGN were comparable to those in meat from the Boer goat. Female respondents gave higher (P < 0.05) sensory scores than male respondents for both cooked and fried meat on aroma intensity. Shona consumers gave higher (P < 0.05) aroma intensity scores than the Xhosa and the Zulu consumers for both cooked and fried meat. In the non-supplemented goats, fried meat for all genotypes was superior (P < 0.05) to the cooked meat for initial impression of juiciness. Age and gender of respondents and thermal iv treatment influenced initial impression of juiciness scores (P < 0.05). The quality of chevon from XLE and NGN was comparable to that of the Boer goat, and dietary supplementation improved most meat quality attributes. Chevon from the supplemented goats had higher consumer sensory scores than chevon from the non-supplemented goats. Keywords: supplementation, meat colour, ultimate pH, consumer sensory evaluation, Xhosa lop eared, Nguni, Boer goats.
- Full Text:
- Date Issued: 2010
Effects of marketing channel on bruising, ultimate pH and colour of beef, and stakeholder perceptions on the quality of beef from cattle slaughtered at smallholder abattoir
- Authors: Vimiso, Peter
- Date: 2010
- Subjects: Beef -- South Africa -- Marketing , Beef -- Quality , Beef cattle -- Breeding -- South Africa , Beef cattle breeds -- South Africa , Color of meat , Beef industry -- South Africa
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11172 , http://hdl.handle.net/10353/d1001009 , Beef -- South Africa -- Marketing , Beef -- Quality , Beef cattle -- Breeding -- South Africa , Beef cattle breeds -- South Africa , Color of meat , Beef industry -- South Africa
- Full Text:
- Date Issued: 2010
- Authors: Vimiso, Peter
- Date: 2010
- Subjects: Beef -- South Africa -- Marketing , Beef -- Quality , Beef cattle -- Breeding -- South Africa , Beef cattle breeds -- South Africa , Color of meat , Beef industry -- South Africa
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11172 , http://hdl.handle.net/10353/d1001009 , Beef -- South Africa -- Marketing , Beef -- Quality , Beef cattle -- Breeding -- South Africa , Beef cattle breeds -- South Africa , Color of meat , Beef industry -- South Africa
- Full Text:
- Date Issued: 2010
Effects of removing Acacia Mearnsii on the water table, soil and vegetation properties in the Tsomo Valley of the Eastern Cape Province, South Africa
- Moyo, Hloniphani Peter Mthunzi
- Authors: Moyo, Hloniphani Peter Mthunzi
- Date: 2010
- Subjects: Plant-water relationships , Acacia mearnsii , Water table , Wattles (Plants) -- South Africa -- Eastern Cape , Streamflow -- South Africa -- Eastern Cape , Groundwater -- South Africa -- Eastern Cape , Groundwater recharge -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Pasture Science)
- Identifier: vital:11173 , http://hdl.handle.net/10353/d1001011 , Plant-water relationships , Acacia mearnsii , Water table , Wattles (Plants) -- South Africa -- Eastern Cape , Streamflow -- South Africa -- Eastern Cape , Groundwater -- South Africa -- Eastern Cape , Groundwater recharge -- South Africa -- Eastern Cape
- Full Text:
- Date Issued: 2010
- Authors: Moyo, Hloniphani Peter Mthunzi
- Date: 2010
- Subjects: Plant-water relationships , Acacia mearnsii , Water table , Wattles (Plants) -- South Africa -- Eastern Cape , Streamflow -- South Africa -- Eastern Cape , Groundwater -- South Africa -- Eastern Cape , Groundwater recharge -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Pasture Science)
- Identifier: vital:11173 , http://hdl.handle.net/10353/d1001011 , Plant-water relationships , Acacia mearnsii , Water table , Wattles (Plants) -- South Africa -- Eastern Cape , Streamflow -- South Africa -- Eastern Cape , Groundwater -- South Africa -- Eastern Cape , Groundwater recharge -- South Africa -- Eastern Cape
- Full Text:
- Date Issued: 2010
Efficient rectenna circuits for microwave wireless power transmission
- Authors: Teru, Agboola Awolola
- Date: 2010
- Subjects: Electric power production -- Technological innovations , Integrated circuits -- Design and construction , Electronic circuit design , Semiconductors -- Design and construction
- Language: English
- Type: Thesis , Masters , MSc (Physics)
- Identifier: vital:11590 , http://hdl.handle.net/10353/481 , Electric power production -- Technological innovations , Integrated circuits -- Design and construction , Electronic circuit design , Semiconductors -- Design and construction
- Description: Miniaturisation has been the holy grail of mobile technology. The ability to move around with our gadgets, especially the ones for communication and entertainment, has been what semiconductor scientists have battled over the past decades. Miniaturisation brings about reduced consumption in power and ease of mobility. However, the main impediment to untethered mobility of our gadgets has been the lack of unlimited power supply. The battery had filled this gap for some time, but due to the increased functionalities of these mobile gadgets, increasing the battery capacity would increase the weight of the device considerably that it would eventually become too heavy to carry around. Moreover, the fact that these batteries need to be recharged means we are still not completely free of power cords. The advent of low powered micro-controllers and sensors has created a huge industry for more powerful devices that consume a lot less power. These devices have encouraged hardware designers to reduce the power consumption of the gadgets. This has encouraged the idea of wireless power transmission on another level. With lots of radio frequency energy all around us, from our cordless phones to the numerous mobile cell sites there has not been a better time to delve more into research on WPT. This study looks at the feasibilities of WPT in small device applications where very low power is consumed to carry out some important functionality. The work done here compared two rectifying circuits’ efficiencies and ways to improve on the overall efficiencies. The results obtained show that the full wave rectifier would be the better option when designing a WPT system as more power can be drawn from the rectenna. The load also had a great role as this determined the amount of power drawn from the circuitry.
- Full Text:
- Date Issued: 2010
- Authors: Teru, Agboola Awolola
- Date: 2010
- Subjects: Electric power production -- Technological innovations , Integrated circuits -- Design and construction , Electronic circuit design , Semiconductors -- Design and construction
- Language: English
- Type: Thesis , Masters , MSc (Physics)
- Identifier: vital:11590 , http://hdl.handle.net/10353/481 , Electric power production -- Technological innovations , Integrated circuits -- Design and construction , Electronic circuit design , Semiconductors -- Design and construction
- Description: Miniaturisation has been the holy grail of mobile technology. The ability to move around with our gadgets, especially the ones for communication and entertainment, has been what semiconductor scientists have battled over the past decades. Miniaturisation brings about reduced consumption in power and ease of mobility. However, the main impediment to untethered mobility of our gadgets has been the lack of unlimited power supply. The battery had filled this gap for some time, but due to the increased functionalities of these mobile gadgets, increasing the battery capacity would increase the weight of the device considerably that it would eventually become too heavy to carry around. Moreover, the fact that these batteries need to be recharged means we are still not completely free of power cords. The advent of low powered micro-controllers and sensors has created a huge industry for more powerful devices that consume a lot less power. These devices have encouraged hardware designers to reduce the power consumption of the gadgets. This has encouraged the idea of wireless power transmission on another level. With lots of radio frequency energy all around us, from our cordless phones to the numerous mobile cell sites there has not been a better time to delve more into research on WPT. This study looks at the feasibilities of WPT in small device applications where very low power is consumed to carry out some important functionality. The work done here compared two rectifying circuits’ efficiencies and ways to improve on the overall efficiencies. The results obtained show that the full wave rectifier would be the better option when designing a WPT system as more power can be drawn from the rectenna. The load also had a great role as this determined the amount of power drawn from the circuitry.
- Full Text:
- Date Issued: 2010
Evaluation of cover crop species for biomass production, weed suppression and maize yields under irrigation in the Eastern Cape Province, South Africa
- Authors: Musunda, Bothwell Zvidzai
- Date: 2010
- Subjects: Cover crops , Biomass energy -- South Africa -- Eastern Cape , No-tillage , Conservation of natural resources -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape , Agricultural systems -- South Africa -- Eastern Cape , Weeds
- Language: English
- Type: Thesis , Masters , MSc Agric (Crop Science)
- Identifier: vital:11867 , http://hdl.handle.net/10353/347 , Cover crops , Biomass energy -- South Africa -- Eastern Cape , No-tillage , Conservation of natural resources -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape , Agricultural systems -- South Africa -- Eastern Cape , Weeds
- Description: Achieving high biomass yields of cover crops has been a challenge to the success of Conservation Agriculture (CA) practices in the Eastern Cape (EC). A study was conducted to evaluate strategies for optimizing cover crop biomass production. Trials were carried out to screen summer and winter cover crops, as well as evaluate intercropping patterns and planting dates for biomass, weed suppression and subsequent maize yield under irrigation. Four summer legume cover crop species were evaluated under a Randomised Complete Block Design (RCBD) design. The cover crops were fertilized with 13.34 kg ha-1 of N, 20 kg ha-1 P and 26.66 kg ha-1 K. In the 2008/09 summer season a maize crop was superimposed on the 2007/08 screening trial under no-till. The crop was fertilized with 60 kg ha-1 of N. An intercropping trial was conducted over two seasons as a way of investigating the best way of incorporating cover crops into farmers cropping systems. This was done bearing in mind the limitation of resources such as land. The trial evaluated 3 factors laid as a 2 x 2 x 3 factorial arranged in a split-plot design. The main factor was cover crop planting date (planting at maize planting or 2 weeks after maize planting). The sub plot factor was intercropping pattern (strip intercropping and between row intercropping). A trial was also conducted to evaluate the effect of planting date (End of April and mid May) and four winter legume cover crop species on cover crop biomass, weed suppression and maize grain yield. The experiment was laid out as a Randomised Complete Block Design (RCBD) replicated 3 times. In the subsequent summer season a maize crop was superimposed on the winter trial to test the residual effects of the cover crop species. Another study was conducted to evaluate winter cereal cover crop species for biomass accumulation, weed suppression and subsequent maize grain yield. The cover crops as well as a weedy fallow control plot treatments were laid out as a Randomised Complete Block Design replicated 3 times. In the subsequent summer season a maize crop was superimposed on the site under no-till to evaluate the residual effect of the cover crops on maize. The results showed sunhemp, cowpea and lablab as the best cover crops with high biomass and weed suppression whilst mucuna was the least. Sunhemp consistently yielded higher cover biomass averaging 11200 kg ha-1 over the two seasons whilst mucuna had a consistently lowest average biomass yield of 4050 kg ha-1. These cover crops were above the critical 6 t ha-1 for effective weed suppression. There was a significant (p<0.01) relationship of cover crop dry weight and weed dry weight in both seasons. Subsequent maize grain yield was significantly higher in the sunhemp plots (64.2 %) than the weedy fallow plot. Mucuna, lablab and cowpea had maize grain yield increases of 16.6%, 33% and 43.2% respectively. Intercropping cover crops at maize planting yielded higher cover crop dry weights than a delay in intercropping cover crops. A delay in intercropping resulted in significantly higher average maize grain yield of 4700 kg ha-1 compared to intercropping at maize planting (3800 kg ha-1) and sole maize (4300 kg ha-1) over the two seasons. Strip intercropping also yielded higher (5000 kg ha- 1) average maize grain yield compared to row intercropping (3600 kg ha-1) and sole maize (4300 kg ha-1). There was a significant (p<0.05) relationship between cover crop dry weight in the 2007/08 season and maize grain yield in the 2008/09 season. Early planting grazing vetch gave the highest biomass yield of 8100 kg ha-1 whilst early planted red clover had the lowest biomass of 635 kg ha-1. Low weed dry weights were also obtained from the early planted grazing vetch as opposed to the other treatments. There was a significant (p<0.001) relationship of cover crop dry weight and weed dry weight. In the subsequent 2008/09 summer season early planted grazing vetch had the highest maize yield of 7500 kg ha-1 which was 56.3 % more than the weedy fallow plot had 4800 kg ha-1. The weedy fallow plot also had high weed infestation than the cover crop plots. There were significant (p<0.01) relationships between cover crop dry weight and maize grain yield, winter weed dry weight and maize grain yield and summer weed dry weight and maize grain yield. The results also showed triticale (13900 kg ha-1) as the best winter cover crop for biomass production. Italian ryegrass (6500 kg ha-1) produced the least amount of biomass. In The subsequent maize crop white oats gave highest maize grain yield (6369 kg ha-1) which was 33 % more than the weedy fallow plot (4784 kg ha- 1). There were also significant (p< 0.01) relationships of maize grain yield and winter weed dry weight, maize grain yield and summer growing weeds. The various studies demonstrated that there is opportunity for high biomass production under small scale farmers irrigated conditions using cover crops both in winter and summer. Best bet cover crops were sunhemp, cowpea and lablab for summer and triticale, white oats, barley, Italian ryegrass and grazing vetch for winter. Cover crops can also be incorporated into farmers cropping systems as sole crops or intercrops within the maize based cropping systems. Strip intercropping can be used by farmers as a way of introducing cover crops. Critical to achievement of high biomass is the time of planting cover crops with high biomass when planting is done early. A 2 week delay in strip intercropping cover crop into maize can be used as a way of incorporating cover crops into farmers cropping systems with minimal maize yield reduction.
- Full Text:
- Date Issued: 2010
- Authors: Musunda, Bothwell Zvidzai
- Date: 2010
- Subjects: Cover crops , Biomass energy -- South Africa -- Eastern Cape , No-tillage , Conservation of natural resources -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape , Agricultural systems -- South Africa -- Eastern Cape , Weeds
- Language: English
- Type: Thesis , Masters , MSc Agric (Crop Science)
- Identifier: vital:11867 , http://hdl.handle.net/10353/347 , Cover crops , Biomass energy -- South Africa -- Eastern Cape , No-tillage , Conservation of natural resources -- South Africa -- Eastern Cape , Agriculture -- South Africa -- Eastern Cape , Agricultural systems -- South Africa -- Eastern Cape , Weeds
- Description: Achieving high biomass yields of cover crops has been a challenge to the success of Conservation Agriculture (CA) practices in the Eastern Cape (EC). A study was conducted to evaluate strategies for optimizing cover crop biomass production. Trials were carried out to screen summer and winter cover crops, as well as evaluate intercropping patterns and planting dates for biomass, weed suppression and subsequent maize yield under irrigation. Four summer legume cover crop species were evaluated under a Randomised Complete Block Design (RCBD) design. The cover crops were fertilized with 13.34 kg ha-1 of N, 20 kg ha-1 P and 26.66 kg ha-1 K. In the 2008/09 summer season a maize crop was superimposed on the 2007/08 screening trial under no-till. The crop was fertilized with 60 kg ha-1 of N. An intercropping trial was conducted over two seasons as a way of investigating the best way of incorporating cover crops into farmers cropping systems. This was done bearing in mind the limitation of resources such as land. The trial evaluated 3 factors laid as a 2 x 2 x 3 factorial arranged in a split-plot design. The main factor was cover crop planting date (planting at maize planting or 2 weeks after maize planting). The sub plot factor was intercropping pattern (strip intercropping and between row intercropping). A trial was also conducted to evaluate the effect of planting date (End of April and mid May) and four winter legume cover crop species on cover crop biomass, weed suppression and maize grain yield. The experiment was laid out as a Randomised Complete Block Design (RCBD) replicated 3 times. In the subsequent summer season a maize crop was superimposed on the winter trial to test the residual effects of the cover crop species. Another study was conducted to evaluate winter cereal cover crop species for biomass accumulation, weed suppression and subsequent maize grain yield. The cover crops as well as a weedy fallow control plot treatments were laid out as a Randomised Complete Block Design replicated 3 times. In the subsequent summer season a maize crop was superimposed on the site under no-till to evaluate the residual effect of the cover crops on maize. The results showed sunhemp, cowpea and lablab as the best cover crops with high biomass and weed suppression whilst mucuna was the least. Sunhemp consistently yielded higher cover biomass averaging 11200 kg ha-1 over the two seasons whilst mucuna had a consistently lowest average biomass yield of 4050 kg ha-1. These cover crops were above the critical 6 t ha-1 for effective weed suppression. There was a significant (p<0.01) relationship of cover crop dry weight and weed dry weight in both seasons. Subsequent maize grain yield was significantly higher in the sunhemp plots (64.2 %) than the weedy fallow plot. Mucuna, lablab and cowpea had maize grain yield increases of 16.6%, 33% and 43.2% respectively. Intercropping cover crops at maize planting yielded higher cover crop dry weights than a delay in intercropping cover crops. A delay in intercropping resulted in significantly higher average maize grain yield of 4700 kg ha-1 compared to intercropping at maize planting (3800 kg ha-1) and sole maize (4300 kg ha-1) over the two seasons. Strip intercropping also yielded higher (5000 kg ha- 1) average maize grain yield compared to row intercropping (3600 kg ha-1) and sole maize (4300 kg ha-1). There was a significant (p<0.05) relationship between cover crop dry weight in the 2007/08 season and maize grain yield in the 2008/09 season. Early planting grazing vetch gave the highest biomass yield of 8100 kg ha-1 whilst early planted red clover had the lowest biomass of 635 kg ha-1. Low weed dry weights were also obtained from the early planted grazing vetch as opposed to the other treatments. There was a significant (p<0.001) relationship of cover crop dry weight and weed dry weight. In the subsequent 2008/09 summer season early planted grazing vetch had the highest maize yield of 7500 kg ha-1 which was 56.3 % more than the weedy fallow plot had 4800 kg ha-1. The weedy fallow plot also had high weed infestation than the cover crop plots. There were significant (p<0.01) relationships between cover crop dry weight and maize grain yield, winter weed dry weight and maize grain yield and summer weed dry weight and maize grain yield. The results also showed triticale (13900 kg ha-1) as the best winter cover crop for biomass production. Italian ryegrass (6500 kg ha-1) produced the least amount of biomass. In The subsequent maize crop white oats gave highest maize grain yield (6369 kg ha-1) which was 33 % more than the weedy fallow plot (4784 kg ha- 1). There were also significant (p< 0.01) relationships of maize grain yield and winter weed dry weight, maize grain yield and summer growing weeds. The various studies demonstrated that there is opportunity for high biomass production under small scale farmers irrigated conditions using cover crops both in winter and summer. Best bet cover crops were sunhemp, cowpea and lablab for summer and triticale, white oats, barley, Italian ryegrass and grazing vetch for winter. Cover crops can also be incorporated into farmers cropping systems as sole crops or intercrops within the maize based cropping systems. Strip intercropping can be used by farmers as a way of introducing cover crops. Critical to achievement of high biomass is the time of planting cover crops with high biomass when planting is done early. A 2 week delay in strip intercropping cover crop into maize can be used as a way of incorporating cover crops into farmers cropping systems with minimal maize yield reduction.
- Full Text:
- Date Issued: 2010
Geographies of juvenile crime: a study of crime in selected high schools in East London, South Africa
- Authors: Ladokun, Ayodele Olanrewaju
- Date: 2010
- Subjects: Juvenile delinquency -- South Africa -- East London , School violence -- South Africa -- East London , Education, Secondary -- South Africa -- East London , High schools -- South Africa -- East London , School management and organization -- South Africa -- East London , Crime--South Africa -- East London
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11507 , http://hdl.handle.net/10353/345 , Juvenile delinquency -- South Africa -- East London , School violence -- South Africa -- East London , Education, Secondary -- South Africa -- East London , High schools -- South Africa -- East London , School management and organization -- South Africa -- East London , Crime--South Africa -- East London
- Description: Youth crime has been and still is a social problem in South Africa. It is a problem that shakes the very fabric of the society. The problem with the youth in modern society is both a national concern and an important subject for academic study. High school environments are where youths converge for learning purposes, but they have also turned to hotspots for crime. Different theories on explanations for high school crime have been developed over time. This particular study, conducted in 2008, adopts the criminal opportunity theory to study the social, economic and the demographic characteristics of selected environments in which high schools are located to determine significant factors that are conducive for high schools to be crime hotspots. Three schools were selected in different neighbourhoods in East London for the study. The study used an intensive case design technique to conduct the research. Different characteristics of the communities in which the schools that were studied were located showed different crime pattern. The Law enforcement agencies also realize these differences and they try to address crime issues in various communities in the study areas individually
- Full Text:
- Date Issued: 2010
- Authors: Ladokun, Ayodele Olanrewaju
- Date: 2010
- Subjects: Juvenile delinquency -- South Africa -- East London , School violence -- South Africa -- East London , Education, Secondary -- South Africa -- East London , High schools -- South Africa -- East London , School management and organization -- South Africa -- East London , Crime--South Africa -- East London
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11507 , http://hdl.handle.net/10353/345 , Juvenile delinquency -- South Africa -- East London , School violence -- South Africa -- East London , Education, Secondary -- South Africa -- East London , High schools -- South Africa -- East London , School management and organization -- South Africa -- East London , Crime--South Africa -- East London
- Description: Youth crime has been and still is a social problem in South Africa. It is a problem that shakes the very fabric of the society. The problem with the youth in modern society is both a national concern and an important subject for academic study. High school environments are where youths converge for learning purposes, but they have also turned to hotspots for crime. Different theories on explanations for high school crime have been developed over time. This particular study, conducted in 2008, adopts the criminal opportunity theory to study the social, economic and the demographic characteristics of selected environments in which high schools are located to determine significant factors that are conducive for high schools to be crime hotspots. Three schools were selected in different neighbourhoods in East London for the study. The study used an intensive case design technique to conduct the research. Different characteristics of the communities in which the schools that were studied were located showed different crime pattern. The Law enforcement agencies also realize these differences and they try to address crime issues in various communities in the study areas individually
- Full Text:
- Date Issued: 2010
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 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
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