A Cost-Efficient Energy Management Model for ICT4D Platforms in Low Resource Communities
- Authors: Mbotoloshi, Dumisani
- Date: 2018
- Subjects: Information technology Communication in community development|
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/14538 , vital:39999
- Description: A couple of Information and Communication Technology (ICT) researches have been conducted in the rural communities of South Africa (SA). This has encouraged the development of ICT services such as e-government, e-commerce, e-judiciary, e-health, e-agriculture and many others. Proper ICT implementation has led to societal development, economic empowerment and sustainable communities. However, this is achieved after intensive planning and stakeholders‟ involvement. It is clear that ICTs require energy to function. Most significantly is the fact that a bulk of ICTs in low resource communities (LRC) are mainly donations and less consideration if any is made on their energy consumption. LRC are regions with minimum access to energy, clean water, educational facilities, health facilities, government facilities, technology etc. There have been debates on whether in LRC ICTs are consuming energy. Most ICTs have been deployed without much consideration on the required energy consumption. On the other hand, less research has been done on the sustainability of ICTs, especially considering that all ICT devices and related platforms rely on the availability of energy. There are a lot of possible low cost energy solutions that are available, which could be used to support ICTs in LRC. However, there are so many ICT services, devices and platforms that are lying idle and not been fully utilized in such areas due to the energy related issues. In most cases, ICT solutions in LRC are introduced mainly with Computer Science and Information Systems researchers, without including other key stakeholders like energy experts. The research presents a Cost Effecient Energy Management Model that could be used to assist ICT for Development (ICT4D) platforms or projects in LRC. Both qualitative and quantitative research methods were used within the Siyakhula Living Lab (SLL) in Eastern Cape (EC) Province of SA. Design Science theory is considered for the designing of the model. The SLL is an ICT project which is undertaken within the Dwesa, Bulembu and Alice rural communities. In this dissertation, Dwesa rural community is the chosen case. The surrounding schools in the communities have been used as the ICT point of contact. Interviews, questionnaires, literature v review, action research, focus group, experiments, formulas and evaluation were the specific methods used to conduct this research. Results show that ICTs deployed in the SLLs are mainly donations which consume much energy. The main source of energy use within the SLLs is electricity. From the three schools that were selected where ICTs have been deployed it was found that the electricity bill has increased enormously. This has caused some schools not to open the computer laboratories, which are supposed to be used by the community members. It was also found that there is no energy management plan or solution in place for the SLL resources. The findings show that ICTs within the SLL are been affected by energy related subjects, though the community has been willing to pay for electricity. The Cost Efficient Energy Management Model is proposed at the end of the dissertation. The model is targeted for ICT service providers and has five (5) main pillars i.e stakeholders‟ engagement, energy and ICT infrastructure, new business models, monitoring and evaluation, and finally awareness and training. The dissertation identified all the ICT resources and services at three selected schools within the SLL and drew up the energy consumption for each school. All schools indicated that there has been an increase in the electricity bill after the introduction of the SLL project. There was a clear indication that no energy expert was involved in the establishment of the SLLs. The dissertation indicates that there is a need for renewable source of energy for ICTs to improve service delivery in LRC. ICT service providers should consider energy subjects when planning for development of such solutions in LRC. This research focuses on designing a low cost ICT energy model to inform on ICTs energy consumption in LRC. It further outlines the possible ICT energy solutions that could be used to benefit targeted communities.
- Full Text:
- Date Issued: 2018
- Authors: Mbotoloshi, Dumisani
- Date: 2018
- Subjects: Information technology Communication in community development|
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/14538 , vital:39999
- Description: A couple of Information and Communication Technology (ICT) researches have been conducted in the rural communities of South Africa (SA). This has encouraged the development of ICT services such as e-government, e-commerce, e-judiciary, e-health, e-agriculture and many others. Proper ICT implementation has led to societal development, economic empowerment and sustainable communities. However, this is achieved after intensive planning and stakeholders‟ involvement. It is clear that ICTs require energy to function. Most significantly is the fact that a bulk of ICTs in low resource communities (LRC) are mainly donations and less consideration if any is made on their energy consumption. LRC are regions with minimum access to energy, clean water, educational facilities, health facilities, government facilities, technology etc. There have been debates on whether in LRC ICTs are consuming energy. Most ICTs have been deployed without much consideration on the required energy consumption. On the other hand, less research has been done on the sustainability of ICTs, especially considering that all ICT devices and related platforms rely on the availability of energy. There are a lot of possible low cost energy solutions that are available, which could be used to support ICTs in LRC. However, there are so many ICT services, devices and platforms that are lying idle and not been fully utilized in such areas due to the energy related issues. In most cases, ICT solutions in LRC are introduced mainly with Computer Science and Information Systems researchers, without including other key stakeholders like energy experts. The research presents a Cost Effecient Energy Management Model that could be used to assist ICT for Development (ICT4D) platforms or projects in LRC. Both qualitative and quantitative research methods were used within the Siyakhula Living Lab (SLL) in Eastern Cape (EC) Province of SA. Design Science theory is considered for the designing of the model. The SLL is an ICT project which is undertaken within the Dwesa, Bulembu and Alice rural communities. In this dissertation, Dwesa rural community is the chosen case. The surrounding schools in the communities have been used as the ICT point of contact. Interviews, questionnaires, literature v review, action research, focus group, experiments, formulas and evaluation were the specific methods used to conduct this research. Results show that ICTs deployed in the SLLs are mainly donations which consume much energy. The main source of energy use within the SLLs is electricity. From the three schools that were selected where ICTs have been deployed it was found that the electricity bill has increased enormously. This has caused some schools not to open the computer laboratories, which are supposed to be used by the community members. It was also found that there is no energy management plan or solution in place for the SLL resources. The findings show that ICTs within the SLL are been affected by energy related subjects, though the community has been willing to pay for electricity. The Cost Efficient Energy Management Model is proposed at the end of the dissertation. The model is targeted for ICT service providers and has five (5) main pillars i.e stakeholders‟ engagement, energy and ICT infrastructure, new business models, monitoring and evaluation, and finally awareness and training. The dissertation identified all the ICT resources and services at three selected schools within the SLL and drew up the energy consumption for each school. All schools indicated that there has been an increase in the electricity bill after the introduction of the SLL project. There was a clear indication that no energy expert was involved in the establishment of the SLLs. The dissertation indicates that there is a need for renewable source of energy for ICTs to improve service delivery in LRC. ICT service providers should consider energy subjects when planning for development of such solutions in LRC. This research focuses on designing a low cost ICT energy model to inform on ICTs energy consumption in LRC. It further outlines the possible ICT energy solutions that could be used to benefit targeted communities.
- Full Text:
- Date Issued: 2018
A derivation of the the black-scholes equation using martingales
- Authors: Nyarko , Ebenezer Narh
- Date: 2018
- Subjects: Mathematical models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14572 , vital:40016
- Description: This work focuses on the application of stochastic differential equations, with martingales, in finance. The emphasis is on the derivation of the Black-Scholes model for the valuation of options. A theoretical framework in stochastic analysis, together with Itô calculus (Kiyoshi Itô), is explored. The Girsanov Theorem is applied in order to transform a modelled stochastic equation based, on predetermined stock and bond prices, into equivalent martingale measures. A replication strategy is then adopted to solve the two equations analytically, by finding the natural logarithm of the expectation of the solution to the stochastic models. We finally compute the resulting solution based on a standard, normal distribution to get the desired outcome of the Black-Scholes model.
- Full Text:
- Date Issued: 2018
- Authors: Nyarko , Ebenezer Narh
- Date: 2018
- Subjects: Mathematical models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14572 , vital:40016
- Description: This work focuses on the application of stochastic differential equations, with martingales, in finance. The emphasis is on the derivation of the Black-Scholes model for the valuation of options. A theoretical framework in stochastic analysis, together with Itô calculus (Kiyoshi Itô), is explored. The Girsanov Theorem is applied in order to transform a modelled stochastic equation based, on predetermined stock and bond prices, into equivalent martingale measures. A replication strategy is then adopted to solve the two equations analytically, by finding the natural logarithm of the expectation of the solution to the stochastic models. We finally compute the resulting solution based on a standard, normal distribution to get the desired outcome of the Black-Scholes model.
- Full Text:
- Date Issued: 2018
An analysis on the use of web-based ontology to support ubiquitous learning in South African secondary schools
- Bamigboye, Oluwatosin Omotoyosi
- Authors: Bamigboye, Oluwatosin Omotoyosi
- Date: 2018
- Subjects: Internet in education World Wide Web Ontology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12859 , vital:39385
- Description: There is certainly a need to upgrade our educational system and this can be done through technology-enhanced learning. Technology-enhanced learning can be achieved by developing a web-based ontology e-learning platform, which allows learning to take place ubiquitously. In achieving this task, this research is focusing on analyzing the use of web-based ontology to support the design and implementation of a ubiquitous learning system in South Africa. The implemented web-based ontology e-learning system was deployed and tested. The system testing was done on two variables (Information retrieval and Scalability) of localhost and client system, with the following testing metrics: time is taken for information retrieval, request time to process the request, transfer rate, time localhost receives request, time to respond, roundtrip time for request and network usage. The metrics testing was achieved using apache benchmarking console and gnuplot application to generate the data captured and performance graph, while Wireshark was also used to test/analyze round trip time and network usage through the deployed system. The results of the findings in this study show that the relationship between student and learning content becomes explicit when using ontology technology in searching, organizing, gathering and development content. Results obtained from information retrieval show that the transfer rate of information on localhost for 100 request @ current level of 5 is 37169.89kb/s, while on the client’s system, the transfer rate was 48494.36kb/s which was due to multiple request on the client’s side. Results obtained on scalability shows the round trip time which was (time to respond-time to request). The longest roundtrip was 8 seconds as a result of network being congested with multiple packets request from various sources trying to access the localhost at the same time while the fastest was 1 seconds. The implications of this results show that web-based ontology e-learning system has a positive input to teaching and learning processes in schools for content retrieval and network usage. The system furthermore shows the relationship adopted by learners and teachers, and also the match needs that arise in between. The contribution of this study adds to the existing discoveries on the use of web-based and knowledge-based ontology.
- Full Text:
- Date Issued: 2018
- Authors: Bamigboye, Oluwatosin Omotoyosi
- Date: 2018
- Subjects: Internet in education World Wide Web Ontology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12859 , vital:39385
- Description: There is certainly a need to upgrade our educational system and this can be done through technology-enhanced learning. Technology-enhanced learning can be achieved by developing a web-based ontology e-learning platform, which allows learning to take place ubiquitously. In achieving this task, this research is focusing on analyzing the use of web-based ontology to support the design and implementation of a ubiquitous learning system in South Africa. The implemented web-based ontology e-learning system was deployed and tested. The system testing was done on two variables (Information retrieval and Scalability) of localhost and client system, with the following testing metrics: time is taken for information retrieval, request time to process the request, transfer rate, time localhost receives request, time to respond, roundtrip time for request and network usage. The metrics testing was achieved using apache benchmarking console and gnuplot application to generate the data captured and performance graph, while Wireshark was also used to test/analyze round trip time and network usage through the deployed system. The results of the findings in this study show that the relationship between student and learning content becomes explicit when using ontology technology in searching, organizing, gathering and development content. Results obtained from information retrieval show that the transfer rate of information on localhost for 100 request @ current level of 5 is 37169.89kb/s, while on the client’s system, the transfer rate was 48494.36kb/s which was due to multiple request on the client’s side. Results obtained on scalability shows the round trip time which was (time to respond-time to request). The longest roundtrip was 8 seconds as a result of network being congested with multiple packets request from various sources trying to access the localhost at the same time while the fastest was 1 seconds. The implications of this results show that web-based ontology e-learning system has a positive input to teaching and learning processes in schools for content retrieval and network usage. The system furthermore shows the relationship adopted by learners and teachers, and also the match needs that arise in between. The contribution of this study adds to the existing discoveries on the use of web-based and knowledge-based ontology.
- Full Text:
- Date Issued: 2018
An evaluation of the impact of the biogas digesters project at Melani village, Eastern Cape, South Africa
- Authors: Mthimunye , Thabiso Vincent
- Date: 2018
- Subjects: Biogas
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14561 , vital:40014
- Description: A study was conducted in Melani rural community of Raymond Mhlaba district in Eastern Cape, with the aim of identifying types of energy sources and households energy utilization. Melani village (32°43’29” S, 27°07’35” E) is 13 km away from Alice, the closest town and its household population is about 350. The survey was conducted with 50% of the randomly chosen households using semi-structured questionnaires and some onset CTA-A hobo current transducers were installed in three households to measure electricity used for either cooking, heating or lighting. The survey shows that electricity (supplied by Eskom) is the main source of energy for cooking, lighting and heating, while paraffin and candles are also used for lighting. The data collected using the data acquisition system has also shown that each household consumes an average of 140 kWh of electricity per month. Assuming this amount of energy being used throughout the year, on average the households consume 1680 kWh of electricity per year. The research concludes that there is a need to promote sustainable energy resources and technologies such as the use of biogas digesters as an alternative source of energy since the households has on average 20 of cattle, 10 of goats, 10 sheep and 4 donkeys. The research has also shown that the economic analysis of the biogas project is financially feasible. The Net present value was high and positive showing the feasibility of the investment on the project. The payback period was implying that the project pays itself off within the service life or within a set payback limit, which must be shorter than the technical service period of 5 years. The research has further shown that the emission factor for carbon dioxide for every 1MWh of electrical energy saved is 1.07 kg and consequently a corresponding volume of avoidance water is 1.40 KL. This can be mentioned that this monthly cost saving in the electrical energy consumption can go a long way in improving the social and economic welfare of the people. More so, it also vi plays a key role in the reduction of the global warming potential and the amount of air pollutant in the atmosphere. The avoidance water also contributed greatly in reducing the total volume of water used in the cooling towers of the coal power generation plant.
- Full Text:
- Date Issued: 2018
- Authors: Mthimunye , Thabiso Vincent
- Date: 2018
- Subjects: Biogas
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14561 , vital:40014
- Description: A study was conducted in Melani rural community of Raymond Mhlaba district in Eastern Cape, with the aim of identifying types of energy sources and households energy utilization. Melani village (32°43’29” S, 27°07’35” E) is 13 km away from Alice, the closest town and its household population is about 350. The survey was conducted with 50% of the randomly chosen households using semi-structured questionnaires and some onset CTA-A hobo current transducers were installed in three households to measure electricity used for either cooking, heating or lighting. The survey shows that electricity (supplied by Eskom) is the main source of energy for cooking, lighting and heating, while paraffin and candles are also used for lighting. The data collected using the data acquisition system has also shown that each household consumes an average of 140 kWh of electricity per month. Assuming this amount of energy being used throughout the year, on average the households consume 1680 kWh of electricity per year. The research concludes that there is a need to promote sustainable energy resources and technologies such as the use of biogas digesters as an alternative source of energy since the households has on average 20 of cattle, 10 of goats, 10 sheep and 4 donkeys. The research has also shown that the economic analysis of the biogas project is financially feasible. The Net present value was high and positive showing the feasibility of the investment on the project. The payback period was implying that the project pays itself off within the service life or within a set payback limit, which must be shorter than the technical service period of 5 years. The research has further shown that the emission factor for carbon dioxide for every 1MWh of electrical energy saved is 1.07 kg and consequently a corresponding volume of avoidance water is 1.40 KL. This can be mentioned that this monthly cost saving in the electrical energy consumption can go a long way in improving the social and economic welfare of the people. More so, it also vi plays a key role in the reduction of the global warming potential and the amount of air pollutant in the atmosphere. The avoidance water also contributed greatly in reducing the total volume of water used in the cooling towers of the coal power generation plant.
- Full Text:
- Date Issued: 2018
Analysis of the security and reliability of packet transmission in Wireless Mesh Networks (WMNs) : a case study of Malicious Packet drop attack
- Adeniji, Victor Oluwatobiloba
- Authors: Adeniji, Victor Oluwatobiloba
- Date: 2018
- Subjects: Wireless communication systems Mobile communication systems
- Language: English
- Type: Thesis , Masters , Computer Science
- Identifier: http://hdl.handle.net/10353/17450 , vital:40969
- Description: Wireless Mesh Networks (WMNs) are known for possessing good attributes such as low up-front cost, easy network maintenance, and reliable service coverage. This has largely made them to be adopted in various areas such as; school campus networks, community networking, pervasive healthcare, office and home automation, emergency rescue operations and ubiquitous wireless networks. The routing nodes are equipped with self-organized and self-configuring capabilities. The routing mechanisms of WMNs depend on the collaboration of all participating nodes for reliable network performance. However, it has been noted that most routing algorithms proposed for WMNs in the last few years are designed with the assumption that all the participating nodes will collaboratively be involved in relaying the data packets originated from a source to a multi-hop destination. Such design approach exposes WMNs to vulnerability such as malicious packet drop attack. Therefore, it is imperative to design and implement secure and reliable packet routing mechanisms to mitigate this type of attack. While there are works that have attempted to implement secure routing approach, the findings in this research unearthed that further research works are required to improve the existing secure routing in order to provide more secure and reliable packet transmission in WMNs, in the event of denial of service (DoS) attacks such black hole malicious pack drop attack. This study further presents an analysis of the impact of the black hole malicious packet drop attack with other influential factors in WMNs. In the study, NS-3 simulator was used with AODV as the routing protocol. The results show that the packet delivery ratio and throughput of WMN under attack decreases sharply as compared to WMN free from attack.
- Full Text:
- Date Issued: 2018
- Authors: Adeniji, Victor Oluwatobiloba
- Date: 2018
- Subjects: Wireless communication systems Mobile communication systems
- Language: English
- Type: Thesis , Masters , Computer Science
- Identifier: http://hdl.handle.net/10353/17450 , vital:40969
- Description: Wireless Mesh Networks (WMNs) are known for possessing good attributes such as low up-front cost, easy network maintenance, and reliable service coverage. This has largely made them to be adopted in various areas such as; school campus networks, community networking, pervasive healthcare, office and home automation, emergency rescue operations and ubiquitous wireless networks. The routing nodes are equipped with self-organized and self-configuring capabilities. The routing mechanisms of WMNs depend on the collaboration of all participating nodes for reliable network performance. However, it has been noted that most routing algorithms proposed for WMNs in the last few years are designed with the assumption that all the participating nodes will collaboratively be involved in relaying the data packets originated from a source to a multi-hop destination. Such design approach exposes WMNs to vulnerability such as malicious packet drop attack. Therefore, it is imperative to design and implement secure and reliable packet routing mechanisms to mitigate this type of attack. While there are works that have attempted to implement secure routing approach, the findings in this research unearthed that further research works are required to improve the existing secure routing in order to provide more secure and reliable packet transmission in WMNs, in the event of denial of service (DoS) attacks such black hole malicious pack drop attack. This study further presents an analysis of the impact of the black hole malicious packet drop attack with other influential factors in WMNs. In the study, NS-3 simulator was used with AODV as the routing protocol. The results show that the packet delivery ratio and throughput of WMN under attack decreases sharply as compared to WMN free from attack.
- Full Text:
- Date Issued: 2018
Assessing the implementation and effects of the Fetsa Tlala Food Initiative Programme in achieving its vision of eradicating household level food insecurity in Lukhanji Local Municipality, Eastern Cape Province, South Africa
- Authors: Njara, L I
- Date: 2018
- Subjects: Poverty -- South Africa -- Eastern Cape Food security -- South Africa -- Eastern Cape Households -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10476 , vital:35484
- Description: Declining agrarian activities in significant parts of the country, even in the subsistence sector, has meant that access to food is increasingly a function of household cash income, hence low-income households experience inadequate access to food. Over 12 million people in South Africa are vulnerable to food insecurity. Since 2013, substantial efforts and large sums of money have been devoted to poverty reduction through government’s Fetsa Tlala Food Production Initiative. Fetsa Tlala was conceptualised as an integrated government framework that seeks to promote food and nutrition security and to address the structural causes of food insecurity, which continue to perpetuate inequality and social exclusion. The main objective of this study is to assess the implementation and effects of Fetsa Tlala. The specific objectives include: to measure the direct and indirect benefits of Fetsa Tlala; to assess the cost-effectiveness of the programme; to evaluate the model of the programme using a social systems approach; and to assess the implementation approach of Fetsa Tlala. A cross-sectional study was carried on a sample of 70 households and four Fetsa Tlala projects in the Eastern Cape. Households were selected using the simple random sampling procedure. Structured and semi-structured interviews using questionnaires were conducted. The research objectives were analysed using both qualitative and quantitative approaches. Among the quantitative approaches used was a micro simulation exercise, which was performed to help understand the cost-effectiveness of the programme. The results show that the business model of the programme is not built with sustainability in mind and the systems approach was ignored when designing the programme. Furthermore, the cost of the programme outweighs its benefits. This study recommends that the programme should take into account human development and build a needs-based approach going forward. Further recommendations are that the government should target relevant partners, and prioritise agricultural insurance, infrastructure and agro-processing.
- Full Text:
- Date Issued: 2018
- Authors: Njara, L I
- Date: 2018
- Subjects: Poverty -- South Africa -- Eastern Cape Food security -- South Africa -- Eastern Cape Households -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10476 , vital:35484
- Description: Declining agrarian activities in significant parts of the country, even in the subsistence sector, has meant that access to food is increasingly a function of household cash income, hence low-income households experience inadequate access to food. Over 12 million people in South Africa are vulnerable to food insecurity. Since 2013, substantial efforts and large sums of money have been devoted to poverty reduction through government’s Fetsa Tlala Food Production Initiative. Fetsa Tlala was conceptualised as an integrated government framework that seeks to promote food and nutrition security and to address the structural causes of food insecurity, which continue to perpetuate inequality and social exclusion. The main objective of this study is to assess the implementation and effects of Fetsa Tlala. The specific objectives include: to measure the direct and indirect benefits of Fetsa Tlala; to assess the cost-effectiveness of the programme; to evaluate the model of the programme using a social systems approach; and to assess the implementation approach of Fetsa Tlala. A cross-sectional study was carried on a sample of 70 households and four Fetsa Tlala projects in the Eastern Cape. Households were selected using the simple random sampling procedure. Structured and semi-structured interviews using questionnaires were conducted. The research objectives were analysed using both qualitative and quantitative approaches. Among the quantitative approaches used was a micro simulation exercise, which was performed to help understand the cost-effectiveness of the programme. The results show that the business model of the programme is not built with sustainability in mind and the systems approach was ignored when designing the programme. Furthermore, the cost of the programme outweighs its benefits. This study recommends that the programme should take into account human development and build a needs-based approach going forward. Further recommendations are that the government should target relevant partners, and prioritise agricultural insurance, infrastructure and agro-processing.
- Full Text:
- Date Issued: 2018
Assessing the income derived from agricultural hawking in Buffalo City Metropolitan Municipality, Eastern Cape, South Africa
- Authors: Seteni, Vuyo
- Date: 2018
- Subjects: Street vendors -- South Africa -- Eastern Cape Street vendors -- South Africa -- Eastern Cape -- Economic conditions
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10167 , vital:35364
- Description: The hawking business has grown profusely in Buffalo City Metropolitan Municipality, to such an extent that street hawkers are found on every street corner of the Metro. The literature suggests that street hawking holds great potential for employment creation for the unskilled population who cannot find employment opportunities in the formal sector. In light of the proliferation of street hawking in BCMM, the study aimed at assessing the performance of agricultural hawkers in the municipality by means of looking at hawkers’ strategies, determining their sales and net income, and ascertaining their level of ‘job satisfaction’. The sample was selected from the population of hawkers in three major towns of BCMM, namely Mdantsane, East London and King William’s Town. A sum of 200 respondents were selected in the study through interval based probability sampling. The study made use of a cross tabulation of the hawkers’ income according to the three main towns. The results revealed that that agricultural hawking contributes to poverty alleviation in Buffalo City Metropolitan Municipality, as the majority of hawkers earn enough to live above the poverty line. A correlation matrix was used to ascertain the strength and direction of association between hawkers’ monthly income and selected independent variables. The study also used an ordered probit model to determine which specific variables affect hawkers’ monthly income generated from fruit and vegetable sales. The results from the model suggest that business training is significantly and positively related to increasing monthly income, as are age, years of experience, and membership of a hawkers’ association. The study recommends that Buffalo City Metropolitan Municipality build new markets and improve the infrastructure of existing markets, and also provide proper sanitation and clean water to avoid unhygienic situations in street hawkers’ markets.
- Full Text:
- Date Issued: 2018
- Authors: Seteni, Vuyo
- Date: 2018
- Subjects: Street vendors -- South Africa -- Eastern Cape Street vendors -- South Africa -- Eastern Cape -- Economic conditions
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10167 , vital:35364
- Description: The hawking business has grown profusely in Buffalo City Metropolitan Municipality, to such an extent that street hawkers are found on every street corner of the Metro. The literature suggests that street hawking holds great potential for employment creation for the unskilled population who cannot find employment opportunities in the formal sector. In light of the proliferation of street hawking in BCMM, the study aimed at assessing the performance of agricultural hawkers in the municipality by means of looking at hawkers’ strategies, determining their sales and net income, and ascertaining their level of ‘job satisfaction’. The sample was selected from the population of hawkers in three major towns of BCMM, namely Mdantsane, East London and King William’s Town. A sum of 200 respondents were selected in the study through interval based probability sampling. The study made use of a cross tabulation of the hawkers’ income according to the three main towns. The results revealed that that agricultural hawking contributes to poverty alleviation in Buffalo City Metropolitan Municipality, as the majority of hawkers earn enough to live above the poverty line. A correlation matrix was used to ascertain the strength and direction of association between hawkers’ monthly income and selected independent variables. The study also used an ordered probit model to determine which specific variables affect hawkers’ monthly income generated from fruit and vegetable sales. The results from the model suggest that business training is significantly and positively related to increasing monthly income, as are age, years of experience, and membership of a hawkers’ association. The study recommends that Buffalo City Metropolitan Municipality build new markets and improve the infrastructure of existing markets, and also provide proper sanitation and clean water to avoid unhygienic situations in street hawkers’ markets.
- Full Text:
- Date Issued: 2018
Calibration and validation of satellite data (images) over inland water bodies and the effect caused by the adjacency towards them
- Authors: Faniso, Zimbini
- Date: 2018
- Subjects: Hydrology Remote sensing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10350 , vital:35400
- Description: Remote sensing of inland water quality is a particularly challenging satellite Earth observation (EO) application. This arises because inland water bodies are small and optically complex targets that are generally dark compared to surrounding land. Inland water bodies are source supplies of water for both living and non-living organisms, that include human beings hence they need an observation. The spatial distribution of water changes over time and that leads to issues in different sectors like agricultural sector, environmental services and ecological issues. Signal reaching the satellite is usually dominated by light scattered in the atmosphere. Aerosols are strongly variable atmospheric constituents and play a major role in generating this unwanted signal which must be quantified and removed before any conclusions about water state and condition. In order to see how the aerosols affected the water state the light scattered in the atmosphere will be observed through electromagnetic spectrum bands in the atmosphere. This study will analyse the visible and near infrared wavebands of the electromagnetic spectrum as well as where it will be easy to distinguish the atmospheric noise types. A field campaign has been executed at Roodeplaat dam near Pretoria relating to Calibration and Validation (CalVal) of the recently launched Sentinel 2 and Sentinel 3 satellites. In situ measurements were taken at Roodeplaat dam simultaneously with the satellite overpass. Atmospheric Radiative Transfer Modelling (RTM) is required to analyse the satellite surface measurement data that is in the form of radiant quantities. Aerosol models for radiative transfer have been evaluated and refined to improve retrieval accuracy of water-leaving radiance at Roodeplaat dam. A retrieval algorithm for water-leaving radiance (Lw) and remote-sensing reflectance has been developed to analyse the sensitivity of the retrieval to aerosol optical properties, sensitivities, as well as proposals for enhanced retrieval methods, are presented.
- Full Text:
- Date Issued: 2018
- Authors: Faniso, Zimbini
- Date: 2018
- Subjects: Hydrology Remote sensing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10350 , vital:35400
- Description: Remote sensing of inland water quality is a particularly challenging satellite Earth observation (EO) application. This arises because inland water bodies are small and optically complex targets that are generally dark compared to surrounding land. Inland water bodies are source supplies of water for both living and non-living organisms, that include human beings hence they need an observation. The spatial distribution of water changes over time and that leads to issues in different sectors like agricultural sector, environmental services and ecological issues. Signal reaching the satellite is usually dominated by light scattered in the atmosphere. Aerosols are strongly variable atmospheric constituents and play a major role in generating this unwanted signal which must be quantified and removed before any conclusions about water state and condition. In order to see how the aerosols affected the water state the light scattered in the atmosphere will be observed through electromagnetic spectrum bands in the atmosphere. This study will analyse the visible and near infrared wavebands of the electromagnetic spectrum as well as where it will be easy to distinguish the atmospheric noise types. A field campaign has been executed at Roodeplaat dam near Pretoria relating to Calibration and Validation (CalVal) of the recently launched Sentinel 2 and Sentinel 3 satellites. In situ measurements were taken at Roodeplaat dam simultaneously with the satellite overpass. Atmospheric Radiative Transfer Modelling (RTM) is required to analyse the satellite surface measurement data that is in the form of radiant quantities. Aerosol models for radiative transfer have been evaluated and refined to improve retrieval accuracy of water-leaving radiance at Roodeplaat dam. A retrieval algorithm for water-leaving radiance (Lw) and remote-sensing reflectance has been developed to analyse the sensitivity of the retrieval to aerosol optical properties, sensitivities, as well as proposals for enhanced retrieval methods, are presented.
- Full Text:
- Date Issued: 2018
Classification of Distinct Fuzzy Subgroups of the Dihedral Group Dp nq for p and q distinct primes and n ∈ N
- Authors: Nxala, Baphumelele Ellen
- Date: 2018
- Subjects: Fuzzy mathematics Fuzzy sets
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14516 , vital:39997
- Description: In this dissertation, we classify distinct fuzzy subgroups of the dihedral group Dpnq, for p and q distinct primes and n ∈ N, under a natural equivalence relation of fuzzy subgroups and a fuzzy isomorphism. We aim to present formulae for the number of maximal chains and the number of distinct fuzzy subgroups of this group. Our study will include some theory on non-abelian groups since the classification of distinct fuzzy subgroups of this group relies on the crisp characterization of maximal chains. We give the definition of a natural equivalence relation introduced by Murali and Makamba in [67] which we will use in this study. Based on this definition, we introduce two counting techniques that we will use to compute the number of distinct fuzzy subgroups of Dpnq. In this dissertation, we use the criss-cut counting technique as our primary method of enumeration, and the cross-cut method serves as a means of verifying results we obtain from our primary method. To classify distinct fuzzy subgroups of this group, we begin by investigating the dihedral groups Dpnq, for p and q distinct primes and specific values of n = 2 and 3 to observe a trend. We classify the flags of these groups using the characterization of flags introduced in [93]. From this characterization, we then present formulae for the number of distinct fuzzy subgroups attributed to the flags of Dp 2q and Dp 3q . To generalise results for Dpnq, for p and q distinct primes and n ∈ N, we characterize the flags of this group and classify them as either cyclic, mdcyclic for 1 ≤ m ≤ n, or b-cyclic. Finally, we establish a general formula for the number of distinct fuzzy subgroups obtainable from these flags. We conclude by comparing results obtained from using our general formula to those obtained by other researchers for the same group. Based on the results from this study, we give an outline of future research work
- Full Text:
- Date Issued: 2018
- Authors: Nxala, Baphumelele Ellen
- Date: 2018
- Subjects: Fuzzy mathematics Fuzzy sets
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14516 , vital:39997
- Description: In this dissertation, we classify distinct fuzzy subgroups of the dihedral group Dpnq, for p and q distinct primes and n ∈ N, under a natural equivalence relation of fuzzy subgroups and a fuzzy isomorphism. We aim to present formulae for the number of maximal chains and the number of distinct fuzzy subgroups of this group. Our study will include some theory on non-abelian groups since the classification of distinct fuzzy subgroups of this group relies on the crisp characterization of maximal chains. We give the definition of a natural equivalence relation introduced by Murali and Makamba in [67] which we will use in this study. Based on this definition, we introduce two counting techniques that we will use to compute the number of distinct fuzzy subgroups of Dpnq. In this dissertation, we use the criss-cut counting technique as our primary method of enumeration, and the cross-cut method serves as a means of verifying results we obtain from our primary method. To classify distinct fuzzy subgroups of this group, we begin by investigating the dihedral groups Dpnq, for p and q distinct primes and specific values of n = 2 and 3 to observe a trend. We classify the flags of these groups using the characterization of flags introduced in [93]. From this characterization, we then present formulae for the number of distinct fuzzy subgroups attributed to the flags of Dp 2q and Dp 3q . To generalise results for Dpnq, for p and q distinct primes and n ∈ N, we characterize the flags of this group and classify them as either cyclic, mdcyclic for 1 ≤ m ≤ n, or b-cyclic. Finally, we establish a general formula for the number of distinct fuzzy subgroups obtainable from these flags. We conclude by comparing results obtained from using our general formula to those obtained by other researchers for the same group. Based on the results from this study, we give an outline of future research work
- Full Text:
- Date Issued: 2018
Correlations between the occurence of virulent helicobacter pylori strains and chronic disease conditions in dyspeptic patients hospitalized in Chris Hani Baragwanath Hospital, Gauteng Province, South Africa
- Authors: Mzukwa, Asisipho
- Date: 2018
- Subjects: Helicobacter pylori infections Helicobacter pylori Bacterial diseases
- Language: English
- Type: Thesis , Masters , Microbiology
- Identifier: http://hdl.handle.net/10353/10885 , vital:35905
- Description: Introduction: Individuals predisposed to different chronic disease conditions such as type 2 diabetes mellitus (T2DM), hypertension (HPT) and human immunodeficiency virus (HIV) might be susceptible to persistent H. pylori colonization, which overtime encourages infection with virulent strains. The presence of different types of H. pylori virulence factors especially cagA, dupA and various combinations of vacA subtypes (s1/m1, s2/m1 and s2m2) confer a higher risk of gastric disease development. Aim: This study seeks to recover H. pylori from gastric biopsy specimen from patients with different chronic disease conditions referred to the GIT unit at Chris Hani Baragwanath Academic Hospital, Soweto, and confirm them and further determine the presence of virulent H. pylori strains in patients with T2DM, HPT and HIV. Methods: Gastric biopsies were obtained from 101 patients with different chronic disease conditions after obtaining consent between August 2017 and February 2018. H. pylori was isolated on selective Colombia blood agar. Presumptive isolates were identified following standard microbiology and biochemical technique. These isolates were confirmed by polymerase chain reaction (PCR) targeting the glmM gene. The H. pylori positive samples were further screened for cagA, dupA and vacA genotypes. Results: H. pylori was recovered from 26 patients, of which 8 were patients with T2DM, 10 with HPT and 8 with HIV. There was no correlation between H. pylori infection and the chronic conditions, but the majority of H. pylori positive participant carried virulent H. pylori strains. The cagA and the dupA genes were more prevalent in T2DM and HPT patients, however the association between these genes and the 2 chronic conditions was not significant. The vacA subtypes common in hypertensive patients compared to the other conditions were the s1m1, s1m2, and s2m2 and the association between these vacA forms and hypertension was significant. Majority of HIV infected patients were found to carry non-virulent H. pylori strains. Conclusion: The prevalence of H. pylori among the general population of patients with T2DM, HPT and HIV was low. Although infected patients are found to be carrying virulent strains of H. pylori, there is no significant association established between the virulent strains and the chronic conditions. Furthermore, HIV-infected patients were found to be carrying non-virulent strains of H. pylori.
- Full Text:
- Date Issued: 2018
- Authors: Mzukwa, Asisipho
- Date: 2018
- Subjects: Helicobacter pylori infections Helicobacter pylori Bacterial diseases
- Language: English
- Type: Thesis , Masters , Microbiology
- Identifier: http://hdl.handle.net/10353/10885 , vital:35905
- Description: Introduction: Individuals predisposed to different chronic disease conditions such as type 2 diabetes mellitus (T2DM), hypertension (HPT) and human immunodeficiency virus (HIV) might be susceptible to persistent H. pylori colonization, which overtime encourages infection with virulent strains. The presence of different types of H. pylori virulence factors especially cagA, dupA and various combinations of vacA subtypes (s1/m1, s2/m1 and s2m2) confer a higher risk of gastric disease development. Aim: This study seeks to recover H. pylori from gastric biopsy specimen from patients with different chronic disease conditions referred to the GIT unit at Chris Hani Baragwanath Academic Hospital, Soweto, and confirm them and further determine the presence of virulent H. pylori strains in patients with T2DM, HPT and HIV. Methods: Gastric biopsies were obtained from 101 patients with different chronic disease conditions after obtaining consent between August 2017 and February 2018. H. pylori was isolated on selective Colombia blood agar. Presumptive isolates were identified following standard microbiology and biochemical technique. These isolates were confirmed by polymerase chain reaction (PCR) targeting the glmM gene. The H. pylori positive samples were further screened for cagA, dupA and vacA genotypes. Results: H. pylori was recovered from 26 patients, of which 8 were patients with T2DM, 10 with HPT and 8 with HIV. There was no correlation between H. pylori infection and the chronic conditions, but the majority of H. pylori positive participant carried virulent H. pylori strains. The cagA and the dupA genes were more prevalent in T2DM and HPT patients, however the association between these genes and the 2 chronic conditions was not significant. The vacA subtypes common in hypertensive patients compared to the other conditions were the s1m1, s1m2, and s2m2 and the association between these vacA forms and hypertension was significant. Majority of HIV infected patients were found to carry non-virulent H. pylori strains. Conclusion: The prevalence of H. pylori among the general population of patients with T2DM, HPT and HIV was low. Although infected patients are found to be carrying virulent strains of H. pylori, there is no significant association established between the virulent strains and the chronic conditions. Furthermore, HIV-infected patients were found to be carrying non-virulent strains of H. pylori.
- Full Text:
- Date Issued: 2018
Design and development of a context sensitive rural development software application for eService provisioning
- Authors: Masikisiki, Lizo
- Date: 2018
- Subjects: Rural development Electronic commerce Computer networks
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15332 , vital:40366
- Description: After more than a decade since South Africa realized the importance of Information and Communication Technology (ICT) and the role it can play to deliver services, the country is still confronted by a number of challenges challenges that hinder the implementation of a fully-fledged ICT-based system in a form of electronic government to better deliver services and information. While rural development remains as one of the country’s greatest concerns, ICT is among approaches and perspectives that are recognized for not only accelerating rural development but also for providing the country’s economic growth. This research was set to investigate approaches to implement ICT solutions for rural development and service provisioning in the context of electronic government. The research focused more on the technical skills to implement such ICT systems for the benefit of rural development and e-government stakeholders that have an interest in design and development of an integrated and interoperable solution to accelerate service delivery, especially in rural communities. A mixed methods approach was used throughout the research accompanied by an evolutionary prototyping to development the desired prototype. A study was then conducted to gain an understanding of the state and the needs of rural communities to date. The results of the study yielded a number of urbanized service providers that rural dwellers need to timeously visit to consume services. Scenarios to design and develop the intended prototypes were then drawn from these results. The overall implementation of the prototypes produced an integrated platform that allows multiple disparate systems to communicate, share and use information. The qualities of the prototype are what this research recommends to relevant to stakeholders in order to implement an integrated and interoperable e-government system that elevates rural development programs and service delivery.
- Full Text:
- Date Issued: 2018
- Authors: Masikisiki, Lizo
- Date: 2018
- Subjects: Rural development Electronic commerce Computer networks
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15332 , vital:40366
- Description: After more than a decade since South Africa realized the importance of Information and Communication Technology (ICT) and the role it can play to deliver services, the country is still confronted by a number of challenges challenges that hinder the implementation of a fully-fledged ICT-based system in a form of electronic government to better deliver services and information. While rural development remains as one of the country’s greatest concerns, ICT is among approaches and perspectives that are recognized for not only accelerating rural development but also for providing the country’s economic growth. This research was set to investigate approaches to implement ICT solutions for rural development and service provisioning in the context of electronic government. The research focused more on the technical skills to implement such ICT systems for the benefit of rural development and e-government stakeholders that have an interest in design and development of an integrated and interoperable solution to accelerate service delivery, especially in rural communities. A mixed methods approach was used throughout the research accompanied by an evolutionary prototyping to development the desired prototype. A study was then conducted to gain an understanding of the state and the needs of rural communities to date. The results of the study yielded a number of urbanized service providers that rural dwellers need to timeously visit to consume services. Scenarios to design and develop the intended prototypes were then drawn from these results. The overall implementation of the prototypes produced an integrated platform that allows multiple disparate systems to communicate, share and use information. The qualities of the prototype are what this research recommends to relevant to stakeholders in order to implement an integrated and interoperable e-government system that elevates rural development programs and service delivery.
- Full Text:
- Date Issued: 2018
Distribution of virulence determinants in Plesiomonas shigelloides and Vibrio species isolated from selected hospital wastewater effluents in the Eastern Cape Province, South Africa
- Authors: Mashudu, Mavhungu
- Date: 2018
- Subjects: Vibrio
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: http://hdl.handle.net/10353/14505 , vital:39996
- Description: Plesiomonas shigelloides and some Vibrio species are amongst the bacteria species classified into the emerging pathogenic bacteria grouping, and they portend increasing virulence and high resistance to some of the most potent antimicrobial agents used as most important and critical lines of defence against pathogenic infectious agents. Hospital wastewater has attracted significant attention as a pool for the regurgitation of pathogens into the environment which eventually becomes a problem to public health. It has been variously reported that hospital wastewater critically serves also as a puddle for microbial genetic interaction with outcomes including the development of resistance to antimicrobial agents among other pathogenic traits. And, in the same vein, exchanges and gene recombination may have been leading to the emergence of virulence determinants not previously known owing to the capacity of hospital wastewater to encompass a vast diversity of pathogenic bacteria and antimicrobial agents at the same material time. Hence, this research aimed at the evaluation of the prevalence of virulence and antibiotic resistance in Plesiomonas shigelloides and some human pathogenic Vibrio species isolated from selected hospital wastewater in the Eastern Cape Province of South Africa. Wastewater samples were collected at two weeks intervals throughout three months sampling duration from hospital wastewater facility in the Eastern Cape Province. The wastewater samples were from the secondary hospital and, tertiary hospital along with Limbede community wastewater facilities based in the Eastern Cape Province of South Africa. The wastewater samples were aseptically screened for the presence of presumptive Plesiomonas shigelloides and selected Vibrio species using the culture-based method. The identity of the presumptive Plesiomonas shigelloides and Vibrio species (Vibrio cholerae, V. fluvialis, V. parahaemolyticus, and V. vulnificus) isolates were confirmed using species specific primers. After that, the presence 14 of virulence determinants and the antimicrobial susceptibility profiles of the positive strains as well as the antimicrobial resistance factors were all determined. The distribution of the presumptive isolates was as follows; 322 Plesiomans shigelloides and 378 Vibrio species respectively. However, upon molecular confirmation studies, 85 out of 322; 26% of the total presumptive isolates, were confirmed as positive for Plesiomans shigelloides and, on the other hand, from the 378 presumptive Vibrio species, 71% (270) was as positive to Vibrio genus, and upon speciation of the positive isolates; 27% (73) was confirmed as Vibrio cholerae, 9% (24) as Vibrio parahaemolyticus, 4% (12) as Vibrio vulnificus and 3% (8) as Vibrio fluvialis. The remaining 57% (153) which was unaccounted for may belong to other Vibrio species not included in this studies. Various virulence determinants were shown to be present in the Vibrio species identified and the degree varied in line with the species. P. shigelloides showed high levels of resistance to impregnated antibiotics (18 different types). The antibiogram characteristics showed P. shigelloides to possess 100% resistance to Ciprofloxacin, Nalidixic acid, Trimethoprim, Ampicillin, Penicillin, Tetracycline, Doxycycline, Erythromycin, and Cephalothin. These findings are of crucial importance to public health and the science of infectology as it gives insight into the role of the hospital wastewater as a puddle for the recombination of antibiotic resistance determinants and virulence emergence in bacteria. On the strength of the finding of this research, it is essential to indicate that there is a need for an immediate review of hospital wastewater disposal process. Some form of treatment or pretreatment of the hospital wastewater is required before discharge into municipal wastewater treatment facilities. And, perhaps, continuous monitoring of hospital wastewater to reduce the risk posed to public health.
- Full Text:
- Date Issued: 2018
- Authors: Mashudu, Mavhungu
- Date: 2018
- Subjects: Vibrio
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: http://hdl.handle.net/10353/14505 , vital:39996
- Description: Plesiomonas shigelloides and some Vibrio species are amongst the bacteria species classified into the emerging pathogenic bacteria grouping, and they portend increasing virulence and high resistance to some of the most potent antimicrobial agents used as most important and critical lines of defence against pathogenic infectious agents. Hospital wastewater has attracted significant attention as a pool for the regurgitation of pathogens into the environment which eventually becomes a problem to public health. It has been variously reported that hospital wastewater critically serves also as a puddle for microbial genetic interaction with outcomes including the development of resistance to antimicrobial agents among other pathogenic traits. And, in the same vein, exchanges and gene recombination may have been leading to the emergence of virulence determinants not previously known owing to the capacity of hospital wastewater to encompass a vast diversity of pathogenic bacteria and antimicrobial agents at the same material time. Hence, this research aimed at the evaluation of the prevalence of virulence and antibiotic resistance in Plesiomonas shigelloides and some human pathogenic Vibrio species isolated from selected hospital wastewater in the Eastern Cape Province of South Africa. Wastewater samples were collected at two weeks intervals throughout three months sampling duration from hospital wastewater facility in the Eastern Cape Province. The wastewater samples were from the secondary hospital and, tertiary hospital along with Limbede community wastewater facilities based in the Eastern Cape Province of South Africa. The wastewater samples were aseptically screened for the presence of presumptive Plesiomonas shigelloides and selected Vibrio species using the culture-based method. The identity of the presumptive Plesiomonas shigelloides and Vibrio species (Vibrio cholerae, V. fluvialis, V. parahaemolyticus, and V. vulnificus) isolates were confirmed using species specific primers. After that, the presence 14 of virulence determinants and the antimicrobial susceptibility profiles of the positive strains as well as the antimicrobial resistance factors were all determined. The distribution of the presumptive isolates was as follows; 322 Plesiomans shigelloides and 378 Vibrio species respectively. However, upon molecular confirmation studies, 85 out of 322; 26% of the total presumptive isolates, were confirmed as positive for Plesiomans shigelloides and, on the other hand, from the 378 presumptive Vibrio species, 71% (270) was as positive to Vibrio genus, and upon speciation of the positive isolates; 27% (73) was confirmed as Vibrio cholerae, 9% (24) as Vibrio parahaemolyticus, 4% (12) as Vibrio vulnificus and 3% (8) as Vibrio fluvialis. The remaining 57% (153) which was unaccounted for may belong to other Vibrio species not included in this studies. Various virulence determinants were shown to be present in the Vibrio species identified and the degree varied in line with the species. P. shigelloides showed high levels of resistance to impregnated antibiotics (18 different types). The antibiogram characteristics showed P. shigelloides to possess 100% resistance to Ciprofloxacin, Nalidixic acid, Trimethoprim, Ampicillin, Penicillin, Tetracycline, Doxycycline, Erythromycin, and Cephalothin. These findings are of crucial importance to public health and the science of infectology as it gives insight into the role of the hospital wastewater as a puddle for the recombination of antibiotic resistance determinants and virulence emergence in bacteria. On the strength of the finding of this research, it is essential to indicate that there is a need for an immediate review of hospital wastewater disposal process. Some form of treatment or pretreatment of the hospital wastewater is required before discharge into municipal wastewater treatment facilities. And, perhaps, continuous monitoring of hospital wastewater to reduce the risk posed to public health.
- Full Text:
- Date Issued: 2018
Dynamic Mathematical Modeling in Chemical Reaction Networks
- Authors: Gurajena, Simba
- Date: 2018
- Subjects: Chemical reaction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11961 , vital:39122
- Description: Many students are familiar with the idea of ecological, financial modeling and modeling in other fields, but modeling in engineering fields is still an area to be looked at. In this discussion the researcher will deal with chemical reaction networks. This will cover areas in chemical reaction, interaction diagrams and the associated models. The discussion will also cover dynamic behaviour of reaction networks. The law of mass action and examples of simple networks will be dealt with. Differential equation models of biochemical and genetic systems are invariantly nonlinear, and as such numerical simulation is used to solve such models. The use of numerical simulation packages will be discussed and separation of timescale and model reduction will form part of the discussion.
- Full Text:
- Date Issued: 2018
- Authors: Gurajena, Simba
- Date: 2018
- Subjects: Chemical reaction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11961 , vital:39122
- Description: Many students are familiar with the idea of ecological, financial modeling and modeling in other fields, but modeling in engineering fields is still an area to be looked at. In this discussion the researcher will deal with chemical reaction networks. This will cover areas in chemical reaction, interaction diagrams and the associated models. The discussion will also cover dynamic behaviour of reaction networks. The law of mass action and examples of simple networks will be dealt with. Differential equation models of biochemical and genetic systems are invariantly nonlinear, and as such numerical simulation is used to solve such models. The use of numerical simulation packages will be discussed and separation of timescale and model reduction will form part of the discussion.
- Full Text:
- Date Issued: 2018
Economic change in town and countryside in the former Transkei : land use, livelihoods and market linkages in Ngcobo, Eastern Cape, South Africa
- Authors: Nikelo, Nqaba Benedictor
- Date: 2018
- Subjects: Homelands (South Africa) Homelands (South Africa) -- Economic conditions
- Language: English
- Type: Thesis , Masters , Agricultural Economics
- Identifier: http://hdl.handle.net/10353/10768 , vital:35757
- Description: In 1913 in South Africa the natives of land act during apartheid resulted to the separation of South Africa. South Africa was divided into two areas where they were black and white areas. This act had a rule that said the black people can only move out of their lands only if employed as labourers by the whites. The white population was one-fifth of the population and was given 92.5 percent of the land while the rest of the population were blacks and they were restricted to stay on the 7.5 percent of land. In the Eastern Cape, two homelands were created: the Transkei (in 1951) and the Ciskei (in 1961). In 1963 the Transkei became the first homeland to be granted the status of 'self-governing territory within the Republic of South Africa’, with the Ciskei following suit in 1972. The apartheid policies caused economic failure and corruption because very little economic and infrastructural development took place in the homelands. According to the ‘legacy perspective’: the former homelands are historically-determined structural poverty traps. The objective of the study is to describe the extent and change of economic function/role of Ngcobo town and linkages with its surrounding villages. Availability or convenient sampling and random sampling techniques were used to collect primary data from farmers and surrounding villages. Descriptive statistics was used to profile farmers as well as the participants in the surrounding villages. Descriptive statistics was used to describe the change in the economy of Ngcobo town and the change in the economy of the surrounding rural areas. Households in the former homelands devote a large share of their total expenditure to food and beverages, and yet it would appear that a relatively small share of this food originates from these same rural areas. The point of departure of this report is the observation that rural areas are diverse, whereby some areas within the former homeland areas in particular exhibit signs of dynamism which are not understandable in terms of the ‘legacy perspective’.
- Full Text:
- Date Issued: 2018
- Authors: Nikelo, Nqaba Benedictor
- Date: 2018
- Subjects: Homelands (South Africa) Homelands (South Africa) -- Economic conditions
- Language: English
- Type: Thesis , Masters , Agricultural Economics
- Identifier: http://hdl.handle.net/10353/10768 , vital:35757
- Description: In 1913 in South Africa the natives of land act during apartheid resulted to the separation of South Africa. South Africa was divided into two areas where they were black and white areas. This act had a rule that said the black people can only move out of their lands only if employed as labourers by the whites. The white population was one-fifth of the population and was given 92.5 percent of the land while the rest of the population were blacks and they were restricted to stay on the 7.5 percent of land. In the Eastern Cape, two homelands were created: the Transkei (in 1951) and the Ciskei (in 1961). In 1963 the Transkei became the first homeland to be granted the status of 'self-governing territory within the Republic of South Africa’, with the Ciskei following suit in 1972. The apartheid policies caused economic failure and corruption because very little economic and infrastructural development took place in the homelands. According to the ‘legacy perspective’: the former homelands are historically-determined structural poverty traps. The objective of the study is to describe the extent and change of economic function/role of Ngcobo town and linkages with its surrounding villages. Availability or convenient sampling and random sampling techniques were used to collect primary data from farmers and surrounding villages. Descriptive statistics was used to profile farmers as well as the participants in the surrounding villages. Descriptive statistics was used to describe the change in the economy of Ngcobo town and the change in the economy of the surrounding rural areas. Households in the former homelands devote a large share of their total expenditure to food and beverages, and yet it would appear that a relatively small share of this food originates from these same rural areas. The point of departure of this report is the observation that rural areas are diverse, whereby some areas within the former homeland areas in particular exhibit signs of dynamism which are not understandable in terms of the ‘legacy perspective’.
- Full Text:
- Date Issued: 2018
Effects of production systems and canola meal supplementation on carcass and meat quality characteristics of spent laying hens
- Authors: Semwogerere, Farouk
- Date: 2018
- Subjects: Broilers (Chickens) -- Feeding and feeds Chickens -- Feeding and feeds Chicken industry -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/9242 , vital:34309
- Description: This study evaluated the carcass and meat quality traits of spent laying hens as influenced by production systems (conventional cages and free range) and the inclusion/exclusion of canola meal in their diets. A total of 30 free range and 60 battery cage reared Lohmann Brown-Elite spent laying hens were obtained from a commercial egg producer. The 30 free range hens (53 weeks of age) and 30 of the caged hens (40 weeks of age) were fed a conventional diet, while the remaining 30 caged hens (48 weeks of age) were fed a diet supplemented with canola meal (20 percent). Carcass, portion and organ weights were determined. Physical attributes and proximate composition were analyzed for, with additional fatty acids and sensory profiles being determined for the effects of canola meal inclusion in the diet. Caged hens had heavier (P ≤ 0.05) warm and cold carcasses, thigh, wing and feet compared to free range hens. The percentages of the breast (26.1 ± 0.51 vs. 28.3 ± 0.28), drum, breast bones, breast thaw and cooking losses and thigh cooking loss were lower (P ≤ 0.05) for caged hens than for free range hens. Free range hens had heavier (P ≤ 0.05) gizzards (33.9 ± 1.04 vs. 30.5 ± 0.73) and bones and a lower (P ≤ 0.05) breast meat percentage (47.3 ± 0.94 vs. 51.7 ± 1.35). Meat redness (a*) (0.54 ± 0.222 vs. 1.40 ± 0.135) and hue angle value, skin redness (a*), breast and thigh, Warner-Bratzler shear force (WBSF) values (breast: 12.37 ± 0.411 vs. 17.10 ± 0.751, thigh: 29.68 ± 0.306 vs. 39.75 ± 0.826), breast moisture and thigh ash content were lower (P ≤ 0.05) for caged hens than free range hens. Caged hens had higher (P ≤ 0.05) thigh thaw loss and breast ash content than free range hens. Canola-fed hens had higher (P ≤ 0.05) drum percentages, breast bone weights and percentages, with lower (P ≤ 0.05) thigh and breast meat percentages. Canola-fed hens had lower (P ≤ 0.05) thaw losses, skin yellowness (b*) and Chroma values, breast fat content with higher cooking losses, skin redness (a*) and hue angle value, as well as breast WBSF (12.37 ± 0.411 vs. 15.43 ± 0.600). Palmitic acid, stearic acid, heneicosanoic acid acid, palmitoleic acid, saturated fatty acids (SFA) (34.0 ± 0.56 vs. 38.7 ± 0.71), n-6:n-3 polyunsaturated fatty acids (PUFA) ratio (5.5 ± 0.13 vs. 7.2 ± 0.28), atherogenic index (IA), thrombogenic index (IT), delta-5 desaturase (D5D, elongase index and thiosterase index were lower (P ≤ 0.05) for canola-fed hen breast meat. Breast meat from conventionally fed hens had lower (P ≤ 0.05) myristic acid, lignoceric acid, nervonic acid, alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), PUFA:SFA ratio (0.7 ± 0.05 vs. 0.9 ± 0.02), n-3 PUFA (3.4 ± 0.31 vs. 5.1 ± 0.17), hypocholesterolemic:Hypercholesterolaemic (h/H), stearoyl-CoA desaturase 16 (SCD16) and stearoyl-CoA desaturase 18 (SCD18). The breast meat from conventionally fed hens had lower (P ≤ 0.05) metallic flavor than that from canola-fed hens. Strong positive correlations were observed for overall aroma with chicken (r = 0.965, P < 0.001) and brothy aroma (r = 0.827, P < 0.001); overall aroma with overall flavor (r = 0.680, P < 0.001), chicken flavor (r = 0.668, P < 0.001) and brothy flavor (r = 0.548, P = 0.006); initial juiciness with sustained juiciness (r = 0.771, P < 0.001) and tenderness (r = 0.537, P = 0.007); sustained juiciness with tenderness (r = 0.790, P < 0.001) and chewiness with residue (r = 0.783, P < 0.001). Whilst strong negative correlations were observed for: sustained juiciness with chewiness (r = -0.655, P = 0.001) and residue (r = 0.783, P < 0.001) and for tenderness with chewiness (r = 0.845, P < 0.001) and residue (r = -0.855, P < 0.001). Results of this study highlight that a free range production system when compared to a conventional cage system increased undesirable carcass and physical meat traits of spent laying hens. On the other hand, canola meal inclusion incorporates beneficial health aspects without affecting the sensory profile of meat derived from spent laying hens, both groups of hens being reared in battery cage system. Spent laying hen breasts can be consumed as a functional food (especially canolafed) since the fat content and composition was observed to be close to that which is recommended for a healthy diet.
- Full Text:
- Date Issued: 2018
- Authors: Semwogerere, Farouk
- Date: 2018
- Subjects: Broilers (Chickens) -- Feeding and feeds Chickens -- Feeding and feeds Chicken industry -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/9242 , vital:34309
- Description: This study evaluated the carcass and meat quality traits of spent laying hens as influenced by production systems (conventional cages and free range) and the inclusion/exclusion of canola meal in their diets. A total of 30 free range and 60 battery cage reared Lohmann Brown-Elite spent laying hens were obtained from a commercial egg producer. The 30 free range hens (53 weeks of age) and 30 of the caged hens (40 weeks of age) were fed a conventional diet, while the remaining 30 caged hens (48 weeks of age) were fed a diet supplemented with canola meal (20 percent). Carcass, portion and organ weights were determined. Physical attributes and proximate composition were analyzed for, with additional fatty acids and sensory profiles being determined for the effects of canola meal inclusion in the diet. Caged hens had heavier (P ≤ 0.05) warm and cold carcasses, thigh, wing and feet compared to free range hens. The percentages of the breast (26.1 ± 0.51 vs. 28.3 ± 0.28), drum, breast bones, breast thaw and cooking losses and thigh cooking loss were lower (P ≤ 0.05) for caged hens than for free range hens. Free range hens had heavier (P ≤ 0.05) gizzards (33.9 ± 1.04 vs. 30.5 ± 0.73) and bones and a lower (P ≤ 0.05) breast meat percentage (47.3 ± 0.94 vs. 51.7 ± 1.35). Meat redness (a*) (0.54 ± 0.222 vs. 1.40 ± 0.135) and hue angle value, skin redness (a*), breast and thigh, Warner-Bratzler shear force (WBSF) values (breast: 12.37 ± 0.411 vs. 17.10 ± 0.751, thigh: 29.68 ± 0.306 vs. 39.75 ± 0.826), breast moisture and thigh ash content were lower (P ≤ 0.05) for caged hens than free range hens. Caged hens had higher (P ≤ 0.05) thigh thaw loss and breast ash content than free range hens. Canola-fed hens had higher (P ≤ 0.05) drum percentages, breast bone weights and percentages, with lower (P ≤ 0.05) thigh and breast meat percentages. Canola-fed hens had lower (P ≤ 0.05) thaw losses, skin yellowness (b*) and Chroma values, breast fat content with higher cooking losses, skin redness (a*) and hue angle value, as well as breast WBSF (12.37 ± 0.411 vs. 15.43 ± 0.600). Palmitic acid, stearic acid, heneicosanoic acid acid, palmitoleic acid, saturated fatty acids (SFA) (34.0 ± 0.56 vs. 38.7 ± 0.71), n-6:n-3 polyunsaturated fatty acids (PUFA) ratio (5.5 ± 0.13 vs. 7.2 ± 0.28), atherogenic index (IA), thrombogenic index (IT), delta-5 desaturase (D5D, elongase index and thiosterase index were lower (P ≤ 0.05) for canola-fed hen breast meat. Breast meat from conventionally fed hens had lower (P ≤ 0.05) myristic acid, lignoceric acid, nervonic acid, alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), PUFA:SFA ratio (0.7 ± 0.05 vs. 0.9 ± 0.02), n-3 PUFA (3.4 ± 0.31 vs. 5.1 ± 0.17), hypocholesterolemic:Hypercholesterolaemic (h/H), stearoyl-CoA desaturase 16 (SCD16) and stearoyl-CoA desaturase 18 (SCD18). The breast meat from conventionally fed hens had lower (P ≤ 0.05) metallic flavor than that from canola-fed hens. Strong positive correlations were observed for overall aroma with chicken (r = 0.965, P < 0.001) and brothy aroma (r = 0.827, P < 0.001); overall aroma with overall flavor (r = 0.680, P < 0.001), chicken flavor (r = 0.668, P < 0.001) and brothy flavor (r = 0.548, P = 0.006); initial juiciness with sustained juiciness (r = 0.771, P < 0.001) and tenderness (r = 0.537, P = 0.007); sustained juiciness with tenderness (r = 0.790, P < 0.001) and chewiness with residue (r = 0.783, P < 0.001). Whilst strong negative correlations were observed for: sustained juiciness with chewiness (r = -0.655, P = 0.001) and residue (r = 0.783, P < 0.001) and for tenderness with chewiness (r = 0.845, P < 0.001) and residue (r = -0.855, P < 0.001). Results of this study highlight that a free range production system when compared to a conventional cage system increased undesirable carcass and physical meat traits of spent laying hens. On the other hand, canola meal inclusion incorporates beneficial health aspects without affecting the sensory profile of meat derived from spent laying hens, both groups of hens being reared in battery cage system. Spent laying hen breasts can be consumed as a functional food (especially canolafed) since the fat content and composition was observed to be close to that which is recommended for a healthy diet.
- Full Text:
- Date Issued: 2018
Evaluating farmers' perceptions on climate variability and the impact of management practices on rangeland condition at Tukulu Farm, South Africa
- Authors: Huza, Siphamandla
- Date: 2018
- Subjects: Rangelands -- South Africa -- Eastern Cape Range management -- South Africa -- Eastern Cape Livestock -- Breeding -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , Pasture Science
- Identifier: http://hdl.handle.net/10353/10586 , vital:35611
- Description: Rangelands are ecological systems largely used for extensive livestock production, which continually play a vital role in developing the economy of rural communities worldwide. These ecosystems also have the potential to provide vital secondary resources like medicinal plants, firewood and wild foods. This study assessed the impacts of management practices on rangeland condition at Tukulu communal farm in the Eastern Cape province of South Africa. Communal farmers’ perceptions were also investigated on vegetation change and awareness to climate variability. A structured questionnaire with open-ended and closed questions was used to interview communal farmers about several components of their rangeland, their awareness to climate variability and their household demographics were recorded. A rangeland condition assessment with the use of a three-tier system was used to determine vegetation condition and assessment of vegetal change over the past ten to twenty years. Botanical species composition, biomass yield, basal cover, woody plant density, browsing units and soil chemical composition were measured. Tukulu communal rangeland was demarcated into three homogenous vegetation units (HVU) namely, open grassland, scattered bushland and dense bushland. Sample sites of (100×50 m)2 with four replicates were constructed in each HVU. Herbaceous vegetation and basal cover were determined along 100 m transects in each sample site using a step-point method. Aboveground biomass production was estimated using a quadrat system following a systematic sampling by cutting all material within 0.25 m2 quadrats located along 100 m transects. Woody plant density (plants/ha), tree equivalents (TE/ha) and browsing unit (BU/ha) were estimated from the number of woody plants, total woody heights and the number of acceptable and available (<1.5 m) woody species. Soil sample analysis was conducted to determine OC, P, K, N, Ca, Mg, Na, Zn, Cu, and Mn and soil pH in all three HVUs. The respondents consisted of 65 percent males and 35 percent females with an average of about five persons per household. The study revealed that communal farmers at Tukulu were fairly knowledgeable about the changes that have occurred in their rangeland. All respondents 100 percent perceived that their rangeland had changed from good to poor condition. This was characterized by the shift from grass dominance to woody plant encroachment. These changes were linked to the perceived changes in climate. Farmers at Tukulu communal area were generally aware of the changes in climate, 95 percent of the respondents’ perceived changes in weather patterns such as changes in rain seasons, hot weather conditions, unpredictable rainfalls, drought, heavy winds and increased temperatures. The results revealed that Tukulu communal rangeland comprised of high species diversity. Twenty-one herbaceous species and 24 woody species were recorded at Tukulu rangeland. The grass species composition was characterised by 71 percent Increaser II species, 24 percent Decreaser and 5 percent Increaser I species. A highly palatable Decreaser species Themeda triandra decreased in abundance from open grassland to scattered bushland. There were no significant differences (p>0.05) in biomass yield in all three HVUs. However, scattered bushland 761.5 kg/ha and dense bushland 735.8 kg/ha had higher biomass yield when compared to open grassland 688.5 kg/ha. Bush encroachment was observed in dense bushland as the woody plant density 4487.5 trees/ha and tree equivalents 3451.3 trees/ha were significantly (P<0.05) higher than the recommended threshold standards of 2400 trees/ha and 2500 TE/ha. Scattered bushland had tree density of 1900 trees/ha and tree-equivalents of 1534.3 TE/ha. Soil macro and micro nutrients differed significantly between the different HVUs. The levels of Na, Ca, Mg, Cu, Mn differed significantly (p<0.05) between HVUs, increasing from open grassland to dense bushland. Organic carbon concentrations were higher under tree canopies in dense bushland. However, the levels of phosphorus and potassium were higher in open grassland than in the wooded areas. Soil pH in scattered bushland (5.3) and dense bushland (5.18) were significantly higher (p<0.05) than in open grassland (4.89). This study shows complications in management policies governing the Tukulu communal area. There is a need to merge both scientific and indigenous ecological knowledge to ensure the desired outcomes, as this could indeed offer some great insights for communal areas. Therefore, a rangeland rehabilitation programme should be implemented at Tukulu communal rangeland, which will address the issue of bush encroachment and implement a rotational grazing system by fencing camps that will be based on acceptable stocking rates.
- Full Text:
- Date Issued: 2018
- Authors: Huza, Siphamandla
- Date: 2018
- Subjects: Rangelands -- South Africa -- Eastern Cape Range management -- South Africa -- Eastern Cape Livestock -- Breeding -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , Pasture Science
- Identifier: http://hdl.handle.net/10353/10586 , vital:35611
- Description: Rangelands are ecological systems largely used for extensive livestock production, which continually play a vital role in developing the economy of rural communities worldwide. These ecosystems also have the potential to provide vital secondary resources like medicinal plants, firewood and wild foods. This study assessed the impacts of management practices on rangeland condition at Tukulu communal farm in the Eastern Cape province of South Africa. Communal farmers’ perceptions were also investigated on vegetation change and awareness to climate variability. A structured questionnaire with open-ended and closed questions was used to interview communal farmers about several components of their rangeland, their awareness to climate variability and their household demographics were recorded. A rangeland condition assessment with the use of a three-tier system was used to determine vegetation condition and assessment of vegetal change over the past ten to twenty years. Botanical species composition, biomass yield, basal cover, woody plant density, browsing units and soil chemical composition were measured. Tukulu communal rangeland was demarcated into three homogenous vegetation units (HVU) namely, open grassland, scattered bushland and dense bushland. Sample sites of (100×50 m)2 with four replicates were constructed in each HVU. Herbaceous vegetation and basal cover were determined along 100 m transects in each sample site using a step-point method. Aboveground biomass production was estimated using a quadrat system following a systematic sampling by cutting all material within 0.25 m2 quadrats located along 100 m transects. Woody plant density (plants/ha), tree equivalents (TE/ha) and browsing unit (BU/ha) were estimated from the number of woody plants, total woody heights and the number of acceptable and available (<1.5 m) woody species. Soil sample analysis was conducted to determine OC, P, K, N, Ca, Mg, Na, Zn, Cu, and Mn and soil pH in all three HVUs. The respondents consisted of 65 percent males and 35 percent females with an average of about five persons per household. The study revealed that communal farmers at Tukulu were fairly knowledgeable about the changes that have occurred in their rangeland. All respondents 100 percent perceived that their rangeland had changed from good to poor condition. This was characterized by the shift from grass dominance to woody plant encroachment. These changes were linked to the perceived changes in climate. Farmers at Tukulu communal area were generally aware of the changes in climate, 95 percent of the respondents’ perceived changes in weather patterns such as changes in rain seasons, hot weather conditions, unpredictable rainfalls, drought, heavy winds and increased temperatures. The results revealed that Tukulu communal rangeland comprised of high species diversity. Twenty-one herbaceous species and 24 woody species were recorded at Tukulu rangeland. The grass species composition was characterised by 71 percent Increaser II species, 24 percent Decreaser and 5 percent Increaser I species. A highly palatable Decreaser species Themeda triandra decreased in abundance from open grassland to scattered bushland. There were no significant differences (p>0.05) in biomass yield in all three HVUs. However, scattered bushland 761.5 kg/ha and dense bushland 735.8 kg/ha had higher biomass yield when compared to open grassland 688.5 kg/ha. Bush encroachment was observed in dense bushland as the woody plant density 4487.5 trees/ha and tree equivalents 3451.3 trees/ha were significantly (P<0.05) higher than the recommended threshold standards of 2400 trees/ha and 2500 TE/ha. Scattered bushland had tree density of 1900 trees/ha and tree-equivalents of 1534.3 TE/ha. Soil macro and micro nutrients differed significantly between the different HVUs. The levels of Na, Ca, Mg, Cu, Mn differed significantly (p<0.05) between HVUs, increasing from open grassland to dense bushland. Organic carbon concentrations were higher under tree canopies in dense bushland. However, the levels of phosphorus and potassium were higher in open grassland than in the wooded areas. Soil pH in scattered bushland (5.3) and dense bushland (5.18) were significantly higher (p<0.05) than in open grassland (4.89). This study shows complications in management policies governing the Tukulu communal area. There is a need to merge both scientific and indigenous ecological knowledge to ensure the desired outcomes, as this could indeed offer some great insights for communal areas. Therefore, a rangeland rehabilitation programme should be implemented at Tukulu communal rangeland, which will address the issue of bush encroachment and implement a rotational grazing system by fencing camps that will be based on acceptable stocking rates.
- Full Text:
- Date Issued: 2018
Evaluation of pharmacological properties and anti-neoplastic potentials of pelargonium iquinans and opuntia stricta extracts using acute leukemia cell lines
- Authors: Izuegbuna, Ogochukwu Osita
- Date: 2018
- Subjects: Pelargoniums Medicinal plants
- Language: English
- Type: Thesis , Masters , M Sc
- Identifier: http://hdl.handle.net/10353/10372 , vital:35442
- Description: Leukaemia like other cancers is a public health issue, and coupled with the issue of drug resistance, toxicity and refractory disease novel treatments both as definitive and supportive care become necessary. The dissertation was designed to evaluate two medicinal plants (Opuntia stricta and Pelargonium inquinans) and their antineoplastic potentials. The phytochemicals analyses were done using standard methods with three different solvents (acetone, aqueous and ethanol). Vitamins analyses was also done using standard methods. The result revealed that vitamin A,C and E were present in the plants. Cell based anti-inflammatory activity were carried out using RAW264.7 macrophages cell, and COX-2 and NO expression as inflammatory markers. Cell based cytotoxicity and antineoplastic activity was investigated using RAW 264.7 macrophages cell, U937 and Jurkat cells. The results of the phytochemical analyses using GC/MS showed that phenols, flavonoids, flavonol, tannin, proanthocyanidin, saponin, alkaloids and phytate were present in these plants. In vitro antioxidant activity was carried out using nitric oxide (NO), alpha, alpha-diphenyl- β-picrylhydrazyl (DPPH), hydrogen peroxide (H2O2), phosphomolybdenum activity, and iron reducing power (FRAP) techniques. The results of the antioxidant activity showed both plants had antioxidant properties that can be attributed to the phytochemical and vitamins contents. The results showed that both plants had anti-inflammatory properties which can also be attributed to their phytochemicals. The GC-MS analysis of the essential oils of both plants showed the presence of monoterpenes, sesquiterpenes, fatty acids, and esters. The results showed that O. stricta extracts have mild cytotoxicity, while P. inquinans have strong cytotoxicity. The cell cycle analysis showed Pelargonium inquinans extracts induced G0/G1 phase arrest and cleaved caspase-3. This study has shown the antineoplastic potential of P. inquinans which may be attributed to some phytochemicals in it such as carophyllene, humulene, beta myrcene and beta pinene.
- Full Text:
- Date Issued: 2018
- Authors: Izuegbuna, Ogochukwu Osita
- Date: 2018
- Subjects: Pelargoniums Medicinal plants
- Language: English
- Type: Thesis , Masters , M Sc
- Identifier: http://hdl.handle.net/10353/10372 , vital:35442
- Description: Leukaemia like other cancers is a public health issue, and coupled with the issue of drug resistance, toxicity and refractory disease novel treatments both as definitive and supportive care become necessary. The dissertation was designed to evaluate two medicinal plants (Opuntia stricta and Pelargonium inquinans) and their antineoplastic potentials. The phytochemicals analyses were done using standard methods with three different solvents (acetone, aqueous and ethanol). Vitamins analyses was also done using standard methods. The result revealed that vitamin A,C and E were present in the plants. Cell based anti-inflammatory activity were carried out using RAW264.7 macrophages cell, and COX-2 and NO expression as inflammatory markers. Cell based cytotoxicity and antineoplastic activity was investigated using RAW 264.7 macrophages cell, U937 and Jurkat cells. The results of the phytochemical analyses using GC/MS showed that phenols, flavonoids, flavonol, tannin, proanthocyanidin, saponin, alkaloids and phytate were present in these plants. In vitro antioxidant activity was carried out using nitric oxide (NO), alpha, alpha-diphenyl- β-picrylhydrazyl (DPPH), hydrogen peroxide (H2O2), phosphomolybdenum activity, and iron reducing power (FRAP) techniques. The results of the antioxidant activity showed both plants had antioxidant properties that can be attributed to the phytochemical and vitamins contents. The results showed that both plants had anti-inflammatory properties which can also be attributed to their phytochemicals. The GC-MS analysis of the essential oils of both plants showed the presence of monoterpenes, sesquiterpenes, fatty acids, and esters. The results showed that O. stricta extracts have mild cytotoxicity, while P. inquinans have strong cytotoxicity. The cell cycle analysis showed Pelargonium inquinans extracts induced G0/G1 phase arrest and cleaved caspase-3. This study has shown the antineoplastic potential of P. inquinans which may be attributed to some phytochemicals in it such as carophyllene, humulene, beta myrcene and beta pinene.
- Full Text:
- Date Issued: 2018
Extraction and characterization of antimicrobial compounds from selected marine invertebrates collected from Phillip's Reef, Port Elizabeth in the Eastern Cape province of South Africa
- Authors: Kibungu, Cuthbert Wasswa
- Date: 2018
- Subjects: Invertebrates Bioactive compounds Anti-infective agents
- Language: English
- Type: Thesis , Masters , Microbiology
- Identifier: http://hdl.handle.net/10353/11751 , vital:39103
- Description: Introduction: The marine environment is rich in the biodiversity of medically significant invertebrate species such as sponges, ascidians, molluscs and bryozoans. Such a diverse environment is a potential source of a great variety of secondary metabolite production. Research in marine natural product discovery is gaining ground with the development of new therapeutic drugs of antimicrobial potential. Aim: This study seeks to evaluate, and identify bioactive compounds obtained from marine invertebrates collected from Phillip’s Reef in Algoa Bay. Methodology: Marine invertebrates were collected from the Phillip’s Reef in Algoa Bay, Port Elizabeth, at a depth of 12 m and the physichochemical parameters at the site of sample collection were recorded onsite. Sampling was done once over the four seasons in South Africa. Sections of each specimen were sent for identification, and extraction of compounds was done using organic solvents [methanol (95percent), hexane (95percent), petroleum ether (95percent), chloroform (95percent) and ethyl acetate (95percent)]. A ratio of 95percent the respective solvents was achieved by the following (1:19), organic solvent combinations [dichloromethane: methanol (1:1), hexane: chloroform: methanol (1:2:1)] and aqueous solution of water. Solvent optimization was done by measuring the absorbance of S. aureus (ATCC 49476) in Mueller Hinton Broth containing crude extracts at 600 nm. The appropriate solvent was then selected for further extraction of bioactive compounds from the specimens. Antimicrobial activity of the crude extracts was evaluated using the standard agar well diffusion method on test pathogens, namely, methicillin-resistant Staphylococcus aureus (ATCC 49476), clostridium difficile (ATCC 9689), Pseudomonas aeruginosa (ATCC 10145), Candida albicans (ATCC 10231) and Aspergillus fumigatus (ATCC 204305). Different concentrations of the crude extracts were used [100percent, 80percent, 60percent, 40percent and 30percent (v:v)] and the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were determined. Selected bioactive crude extracts were further evaluated for phytochemicals before being purified by subjecting them to Sephadex-G75 column chromatography, using 75percent ethyl acetate as the mobile phase. Bioactive crude extracts fractions obtained following column chromatography were subjected to Electron Spray Ionization Time of Flight (ESI-TOF) analysis using The Bruker Daltonics maXis compact ESI Quadrupole TOF instrument to detect and identify compounds present. Peak identification was done using the blast software contained in Open Chrom Community Edition (Alder), open source software for chromatography and mass spectrometry spectrum analysis. Results: Sixty-seven different marine invertebrate species were collected over the 4 seasons. A mean temperature of 17.35oC ± 2.06 was recorded over all four seasons with the Autumn exhibiting the highest temperature (20oC). Salinity readings obtained ranged between 35.12 psu and 35.27 psu. A stable mean pH range of 8.08–8.78 was also recorded across all four seasons. Salinity and pH readings conformed to the standards set by the South African Water Quality Guidelines. The Spring season exhibited the highest turbidity of 2.97 NTU compared to other seasons. Ethyl acetate and dichloromethane: methanol (1:1) extracts yielded the best inhibitory results. Approximately 60percent (4/67) of the marine invertebrate specimens showed bioactivity against some of the test pathogens. Both ethyl acetate and dichloromethane methanol crude extracts of S14 and S34 showed a broad spectrum of antimicrobial activity against both bacteria and fungi. The C6 ethyl acetate crude extracts were highly active against MRSA, as inhibition zones of 45 mm were observed. MIC at 30percent concentrations was observed for very few crude extracts against the five pathogens. Sixty-three ethyl acetate crude extracts contained phytochemicals while only 35 dichloromethane: methanol crude extracts contained phytochemicals. Neither ethyl acetate and dichloromethane: methanol crude extracts of S34 (Psammopsinia sp. 1) that were biologically active had any phytochemicals. Canadine, Ginkolide A, Apigenin, Amygdalin, 10-hydroxy-Camptothecin, Catechin, Beta-Peltatin and 6 Ethoxy-3(4'-hydroxyphenyl)-4-methylcoumarin were identified in the crude extracts. Conclusion: Marine invertebrate species located at Phillip’s Reef produce compounds with antimicrobial potential. These compounds are biologically active against human pathogenic microorganisms. The best solvent to use for the extraction of these biologically significant metabolites is ethyl acetate, as this study achieved outstanding results from ethyl acetate crude extracts in the form of high zones of inhibition, for example the sponge Ectyonopsis flabellate, which exhibited mean inhibition zones of 45 mm against Aspergillus fumigatus. Similar bioactivity was also observed with Tedania (Tedania) Stylonychaeta against Methicillin Resistant Staphylococcus aureus. This is the first study done on some of the marine sponges and ascidians in the Phillip’s Reef, and therefore further evaluation of the purified compounds is necessary in order to obtain the identity of the pure compounds and possibly determine the mechanism of action, and synthesize structural analogues for further studies.
- Full Text:
- Date Issued: 2018
- Authors: Kibungu, Cuthbert Wasswa
- Date: 2018
- Subjects: Invertebrates Bioactive compounds Anti-infective agents
- Language: English
- Type: Thesis , Masters , Microbiology
- Identifier: http://hdl.handle.net/10353/11751 , vital:39103
- Description: Introduction: The marine environment is rich in the biodiversity of medically significant invertebrate species such as sponges, ascidians, molluscs and bryozoans. Such a diverse environment is a potential source of a great variety of secondary metabolite production. Research in marine natural product discovery is gaining ground with the development of new therapeutic drugs of antimicrobial potential. Aim: This study seeks to evaluate, and identify bioactive compounds obtained from marine invertebrates collected from Phillip’s Reef in Algoa Bay. Methodology: Marine invertebrates were collected from the Phillip’s Reef in Algoa Bay, Port Elizabeth, at a depth of 12 m and the physichochemical parameters at the site of sample collection were recorded onsite. Sampling was done once over the four seasons in South Africa. Sections of each specimen were sent for identification, and extraction of compounds was done using organic solvents [methanol (95percent), hexane (95percent), petroleum ether (95percent), chloroform (95percent) and ethyl acetate (95percent)]. A ratio of 95percent the respective solvents was achieved by the following (1:19), organic solvent combinations [dichloromethane: methanol (1:1), hexane: chloroform: methanol (1:2:1)] and aqueous solution of water. Solvent optimization was done by measuring the absorbance of S. aureus (ATCC 49476) in Mueller Hinton Broth containing crude extracts at 600 nm. The appropriate solvent was then selected for further extraction of bioactive compounds from the specimens. Antimicrobial activity of the crude extracts was evaluated using the standard agar well diffusion method on test pathogens, namely, methicillin-resistant Staphylococcus aureus (ATCC 49476), clostridium difficile (ATCC 9689), Pseudomonas aeruginosa (ATCC 10145), Candida albicans (ATCC 10231) and Aspergillus fumigatus (ATCC 204305). Different concentrations of the crude extracts were used [100percent, 80percent, 60percent, 40percent and 30percent (v:v)] and the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were determined. Selected bioactive crude extracts were further evaluated for phytochemicals before being purified by subjecting them to Sephadex-G75 column chromatography, using 75percent ethyl acetate as the mobile phase. Bioactive crude extracts fractions obtained following column chromatography were subjected to Electron Spray Ionization Time of Flight (ESI-TOF) analysis using The Bruker Daltonics maXis compact ESI Quadrupole TOF instrument to detect and identify compounds present. Peak identification was done using the blast software contained in Open Chrom Community Edition (Alder), open source software for chromatography and mass spectrometry spectrum analysis. Results: Sixty-seven different marine invertebrate species were collected over the 4 seasons. A mean temperature of 17.35oC ± 2.06 was recorded over all four seasons with the Autumn exhibiting the highest temperature (20oC). Salinity readings obtained ranged between 35.12 psu and 35.27 psu. A stable mean pH range of 8.08–8.78 was also recorded across all four seasons. Salinity and pH readings conformed to the standards set by the South African Water Quality Guidelines. The Spring season exhibited the highest turbidity of 2.97 NTU compared to other seasons. Ethyl acetate and dichloromethane: methanol (1:1) extracts yielded the best inhibitory results. Approximately 60percent (4/67) of the marine invertebrate specimens showed bioactivity against some of the test pathogens. Both ethyl acetate and dichloromethane methanol crude extracts of S14 and S34 showed a broad spectrum of antimicrobial activity against both bacteria and fungi. The C6 ethyl acetate crude extracts were highly active against MRSA, as inhibition zones of 45 mm were observed. MIC at 30percent concentrations was observed for very few crude extracts against the five pathogens. Sixty-three ethyl acetate crude extracts contained phytochemicals while only 35 dichloromethane: methanol crude extracts contained phytochemicals. Neither ethyl acetate and dichloromethane: methanol crude extracts of S34 (Psammopsinia sp. 1) that were biologically active had any phytochemicals. Canadine, Ginkolide A, Apigenin, Amygdalin, 10-hydroxy-Camptothecin, Catechin, Beta-Peltatin and 6 Ethoxy-3(4'-hydroxyphenyl)-4-methylcoumarin were identified in the crude extracts. Conclusion: Marine invertebrate species located at Phillip’s Reef produce compounds with antimicrobial potential. These compounds are biologically active against human pathogenic microorganisms. The best solvent to use for the extraction of these biologically significant metabolites is ethyl acetate, as this study achieved outstanding results from ethyl acetate crude extracts in the form of high zones of inhibition, for example the sponge Ectyonopsis flabellate, which exhibited mean inhibition zones of 45 mm against Aspergillus fumigatus. Similar bioactivity was also observed with Tedania (Tedania) Stylonychaeta against Methicillin Resistant Staphylococcus aureus. This is the first study done on some of the marine sponges and ascidians in the Phillip’s Reef, and therefore further evaluation of the purified compounds is necessary in order to obtain the identity of the pure compounds and possibly determine the mechanism of action, and synthesize structural analogues for further studies.
- Full Text:
- Date Issued: 2018
Factors influencing the hygienic quality of milk yield from smallholder dairy herds in the Eastern Cape Province, South Africa
- Authors: Dube, Hlengani Paul
- Date: 2018
- Subjects: Milk hygiene
- Language: English
- Type: Thesis , Masters , Animal Science
- Identifier: http://hdl.handle.net/10353/10790 , vital:35761
- Description: The objective of the study was to identify factors influencing the hygienic quality of milk of smallholder dairy herds in the Eastern Cape Province of South Africa. Three smallholder herds participating in the National Animal recording scheme and located in Alexandria and East London District Municipalities were used. 90 dairy animals from 3 farms were used, each farm consisting of 30 animals. Three breeds of ten animals were randomly chosen from each farm, the three breeds include, (Holstein, Jersey and Crosses), and four seasons, (autumn, winter, spring and summer) were used to determine the effects of breed and season on the hygienic quality of milk. Milk components included fat percentage, protein percentage, lactose percentage, milk urea nitrogen, milk yield and somatic cell counts (SCC). A total of 1080 milk samples were collected in the afternoon after milking. Procedure of general linear model of SAS was used to determine the effects of breed, season and farm of the milk quality parameters. Means were separated by PDIFF test (α = 0.05). Fixed effects of season, breed and farm, along with 2 way interactions of season and farm and breed and farm were determined. An evaluation template was used to identify the factors affecting hygienic quality of milk. Descriptive statistics (frequencies and percentages) were used. In order to investigate associations between variables of interest, a Pearson Chi-square test was done. The Chi-square test was also used to determine significantly independent findings at a P < 0.10 level of confidence. Cross tabulations were done to establish a basis for comparison and to find out if there is a relationship between two or more variables. The breeds kept within the smallholder dairy herds include Holstein, Jersey, Ayrshire, Guernsey and their Crosses. All farmers’practised pasture based dairy farming system, which includes exclusive dairy production and dairy with other animals like poultry and pigs. 33.33 percent of the smallholder herds use the machine milking method, while 66.67 percent use both the machine and hand milking methods. Milking time is uniform throughout the farms, with milking being done twice a day, in the morning and afternoon. The hygiene practices of the farms were largely similar from farm to farm. Before milking, the udders and teats of animals are washed with clean running water. After milking, the teats of the animals are dipped in teat dip to prevent mastitis. All the farmers’ dairy milking facilities have a permanent water source with continuous supply throughout the year. The water sources vary according to farms, with 33.33% use boreholes, while 66.67 percent utilise rivers and springs. Farmers face numerous challenges such as ageing and dilapidated equipment and infrastructure, limited capital that reduces the number of employees on farm and the purchase of feed inputs to support the milking procedure. Effect of season on milk quality, were significantly (P <0.001) different in milk yield, lactose, and somatic cell counts, and significant different at (P < 0.05) for milk urea nitrogen. High milk yields are observed in spring, and winter, while low milk yields are observed in autumn. High values for fat and protein content were observed in winter. High somatic cell counts were observed in autumn than in spring summer and winter. Effects of farm, on milk quality were significantly (P < 0.001) different on milk yield, fat, protein, lactose, and milk urea nitrogen, and significantly different (P < 0.01) for somatic cell counts. Milk yields varied from 14.03kg/day, 15.51kg/day, and 20.12kg/day, fat percentage varied from 4.52 percent, 4.36 percent, and 4.18 percent, protein percentages of 3.55 percent, 3.44 percent, and 3.47 percent, lactose percentage of 4.47 percent, 4.65 percent, and 4.69 percent, somatic cell counts of 588.42cells/ml, 308.90cells/ml, and 437.43cells/ml, and milk urea nitrogen of 9.84mg/100ml, 10.03mg/100ml, and 10.91mg/100ml for High heaven, Soqhayisa and Matshibele farms respectively. Effect of breed on milk quality, were significantly (P < 0.001) different for milk yield, fat and protein percentage. Milk yields amongst breeds varied at 15.57kg/day, 17.92kg/day, and 16.18kg/day, fat percentages of 4.51 percent, 4.18 percent, and 4.37 percent, protein percentages of 3.55 percent, 3.39 percent, and 3.52 percent, for Jersey, Holstein Cross bred breeds respectively. There were no differences in lactose percentage, somatic cell counts, and milk urea nitrogen amongst breeds. The interaction between farm and season had an effect on milk yield (P < 0.0004), lactose (P < 0.0001), somatic cell counts (P < 0.0001), milk urea nitrogen (P < 0.0019). Milk fat and protein had no effect of farm and season. The interaction between farm and breed had an effect on milk yield (P < 0.0018), fat (P < 0.0001), protein (P < 0.0001), lactose (P < 0.0227), milk urea nitrogen (P < 0.0373). Farm and breed had no effect onsomatic cell counts. The effect of the farm had a greater detrimental effect on the variations in milk composition within the season and the breed. Milk quality is mainly affected by the farm management practices which at times are affected by the farmer’s resources to achieve the basic routine activities for clean milk. Improving the hygienic practises such as udder cleaning, removal of feed from the troughs, and environmental sanitation will increase milk quality in smallholder herds. Smallholder dairy herds were able to meet the milk quality standards of low somatic cell counts that are acceptable as grade A milk.
- Full Text:
- Date Issued: 2018
- Authors: Dube, Hlengani Paul
- Date: 2018
- Subjects: Milk hygiene
- Language: English
- Type: Thesis , Masters , Animal Science
- Identifier: http://hdl.handle.net/10353/10790 , vital:35761
- Description: The objective of the study was to identify factors influencing the hygienic quality of milk of smallholder dairy herds in the Eastern Cape Province of South Africa. Three smallholder herds participating in the National Animal recording scheme and located in Alexandria and East London District Municipalities were used. 90 dairy animals from 3 farms were used, each farm consisting of 30 animals. Three breeds of ten animals were randomly chosen from each farm, the three breeds include, (Holstein, Jersey and Crosses), and four seasons, (autumn, winter, spring and summer) were used to determine the effects of breed and season on the hygienic quality of milk. Milk components included fat percentage, protein percentage, lactose percentage, milk urea nitrogen, milk yield and somatic cell counts (SCC). A total of 1080 milk samples were collected in the afternoon after milking. Procedure of general linear model of SAS was used to determine the effects of breed, season and farm of the milk quality parameters. Means were separated by PDIFF test (α = 0.05). Fixed effects of season, breed and farm, along with 2 way interactions of season and farm and breed and farm were determined. An evaluation template was used to identify the factors affecting hygienic quality of milk. Descriptive statistics (frequencies and percentages) were used. In order to investigate associations between variables of interest, a Pearson Chi-square test was done. The Chi-square test was also used to determine significantly independent findings at a P < 0.10 level of confidence. Cross tabulations were done to establish a basis for comparison and to find out if there is a relationship between two or more variables. The breeds kept within the smallholder dairy herds include Holstein, Jersey, Ayrshire, Guernsey and their Crosses. All farmers’practised pasture based dairy farming system, which includes exclusive dairy production and dairy with other animals like poultry and pigs. 33.33 percent of the smallholder herds use the machine milking method, while 66.67 percent use both the machine and hand milking methods. Milking time is uniform throughout the farms, with milking being done twice a day, in the morning and afternoon. The hygiene practices of the farms were largely similar from farm to farm. Before milking, the udders and teats of animals are washed with clean running water. After milking, the teats of the animals are dipped in teat dip to prevent mastitis. All the farmers’ dairy milking facilities have a permanent water source with continuous supply throughout the year. The water sources vary according to farms, with 33.33% use boreholes, while 66.67 percent utilise rivers and springs. Farmers face numerous challenges such as ageing and dilapidated equipment and infrastructure, limited capital that reduces the number of employees on farm and the purchase of feed inputs to support the milking procedure. Effect of season on milk quality, were significantly (P <0.001) different in milk yield, lactose, and somatic cell counts, and significant different at (P < 0.05) for milk urea nitrogen. High milk yields are observed in spring, and winter, while low milk yields are observed in autumn. High values for fat and protein content were observed in winter. High somatic cell counts were observed in autumn than in spring summer and winter. Effects of farm, on milk quality were significantly (P < 0.001) different on milk yield, fat, protein, lactose, and milk urea nitrogen, and significantly different (P < 0.01) for somatic cell counts. Milk yields varied from 14.03kg/day, 15.51kg/day, and 20.12kg/day, fat percentage varied from 4.52 percent, 4.36 percent, and 4.18 percent, protein percentages of 3.55 percent, 3.44 percent, and 3.47 percent, lactose percentage of 4.47 percent, 4.65 percent, and 4.69 percent, somatic cell counts of 588.42cells/ml, 308.90cells/ml, and 437.43cells/ml, and milk urea nitrogen of 9.84mg/100ml, 10.03mg/100ml, and 10.91mg/100ml for High heaven, Soqhayisa and Matshibele farms respectively. Effect of breed on milk quality, were significantly (P < 0.001) different for milk yield, fat and protein percentage. Milk yields amongst breeds varied at 15.57kg/day, 17.92kg/day, and 16.18kg/day, fat percentages of 4.51 percent, 4.18 percent, and 4.37 percent, protein percentages of 3.55 percent, 3.39 percent, and 3.52 percent, for Jersey, Holstein Cross bred breeds respectively. There were no differences in lactose percentage, somatic cell counts, and milk urea nitrogen amongst breeds. The interaction between farm and season had an effect on milk yield (P < 0.0004), lactose (P < 0.0001), somatic cell counts (P < 0.0001), milk urea nitrogen (P < 0.0019). Milk fat and protein had no effect of farm and season. The interaction between farm and breed had an effect on milk yield (P < 0.0018), fat (P < 0.0001), protein (P < 0.0001), lactose (P < 0.0227), milk urea nitrogen (P < 0.0373). Farm and breed had no effect onsomatic cell counts. The effect of the farm had a greater detrimental effect on the variations in milk composition within the season and the breed. Milk quality is mainly affected by the farm management practices which at times are affected by the farmer’s resources to achieve the basic routine activities for clean milk. Improving the hygienic practises such as udder cleaning, removal of feed from the troughs, and environmental sanitation will increase milk quality in smallholder herds. Smallholder dairy herds were able to meet the milk quality standards of low somatic cell counts that are acceptable as grade A milk.
- Full Text:
- Date Issued: 2018
Farmers' perceptions of insect pests in the Eastern Cape maize-based cropping systems and the effects of crop residue management on insect pest populations
- Authors: Kadango, Tendayi Lovemore
- Date: 2018
- Subjects: Cropping systems Crop residue management Corn -- Diseases and pests
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6202 , vital:29507
- Description: Maize (Zea mays L.) is one of the most important crops in South Africa that is cultivated for food, feed and as a cash crop. Maize in the Eastern Cape is typically grown for consumption and the Province is one of the least producers owing to small landholdings, poor production conditions and pests. This study investigated: (i) the different maize cropping systems smallholder farmers practice in the Eastern Cape (EC), (ii) the major maize insect pests within the identified cropping systems, (iii) the perceptions of Eastern Cape smallholder maize farmers on the effects of insect pests, and (iv) the effects of crop residues on insect pests’ population dynamics. Four major cropping systems namely: maize sole cropping without rotations by government sponsored farmers (GCP) (94 percent), maize intercropping without rotations by independent farmers (IF) (79 percent), maize sole cropping without rotations by IF (67 percent) and maize intercropping without rotations by GCP (61 percent) were identified. The choice of a cropping system by the smallholder farmers was significantly influenced by source of sponsorship, the difference in their district localities, tenure system, availability of inputs and farming equipment, percentage of farmland farmers allocate to maize, maize varieties, farming experience, fallow operations and access to irrigation facilities. The major constraints faced by the farmers in maize production are the attack by insect pests, weeds competition, drought, the lack of fencing around the fields and destruction by mammals. The major insect pests identified were stalk borers (Busseola fusca, Chilo partellus), cutworms (Agrotis spp.), aphids (Rhopalosiphum maidis), bollworms (Helicoverpa armigera) and weevils (Sitophylus spp.). The most popular control measures employed were the use of GM maize and pesticides. Results from the field trial showed that field crickets were the major ground dwelling insect pests observed followed by bollworms and cutworms. However, there were no significant influence of residue retention on the insects’ diversity indices, richness, and evenness. Above ground insects sampling revealed the domination by four major insects namely, cutworms, maize stalk borer, bollworms, and spotted stalk borer. Residue management significantly influenced the infestation by spotted stalk borer only on maize plots. However, the general trend was that there was less infestation by the insects in plots where residues were retained than the ones with residue removed. Results from the study indicate that government sponsorship is significantly influencing the maize cropping systems of the smallholder farmers of the Eastern Cape.
- Full Text:
- Date Issued: 2018
- Authors: Kadango, Tendayi Lovemore
- Date: 2018
- Subjects: Cropping systems Crop residue management Corn -- Diseases and pests
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6202 , vital:29507
- Description: Maize (Zea mays L.) is one of the most important crops in South Africa that is cultivated for food, feed and as a cash crop. Maize in the Eastern Cape is typically grown for consumption and the Province is one of the least producers owing to small landholdings, poor production conditions and pests. This study investigated: (i) the different maize cropping systems smallholder farmers practice in the Eastern Cape (EC), (ii) the major maize insect pests within the identified cropping systems, (iii) the perceptions of Eastern Cape smallholder maize farmers on the effects of insect pests, and (iv) the effects of crop residues on insect pests’ population dynamics. Four major cropping systems namely: maize sole cropping without rotations by government sponsored farmers (GCP) (94 percent), maize intercropping without rotations by independent farmers (IF) (79 percent), maize sole cropping without rotations by IF (67 percent) and maize intercropping without rotations by GCP (61 percent) were identified. The choice of a cropping system by the smallholder farmers was significantly influenced by source of sponsorship, the difference in their district localities, tenure system, availability of inputs and farming equipment, percentage of farmland farmers allocate to maize, maize varieties, farming experience, fallow operations and access to irrigation facilities. The major constraints faced by the farmers in maize production are the attack by insect pests, weeds competition, drought, the lack of fencing around the fields and destruction by mammals. The major insect pests identified were stalk borers (Busseola fusca, Chilo partellus), cutworms (Agrotis spp.), aphids (Rhopalosiphum maidis), bollworms (Helicoverpa armigera) and weevils (Sitophylus spp.). The most popular control measures employed were the use of GM maize and pesticides. Results from the field trial showed that field crickets were the major ground dwelling insect pests observed followed by bollworms and cutworms. However, there were no significant influence of residue retention on the insects’ diversity indices, richness, and evenness. Above ground insects sampling revealed the domination by four major insects namely, cutworms, maize stalk borer, bollworms, and spotted stalk borer. Residue management significantly influenced the infestation by spotted stalk borer only on maize plots. However, the general trend was that there was less infestation by the insects in plots where residues were retained than the ones with residue removed. Results from the study indicate that government sponsorship is significantly influencing the maize cropping systems of the smallholder farmers of the Eastern Cape.
- Full Text:
- Date Issued: 2018