Curriculum recontextualising using gardens for the health promotion in the life orientation learning area of the senior phase
- Authors: Jenkins, Msawenkosi Wiseman
- Date: 2008
- Subjects: Environmental education -- South Africa -- Eastern Cape -- Case studies School gardens -- South Africa -- Eastern Cape Gardening -- Study and teaching (Secondary) -- South Africa -- Eastern Cape Environmental education -- Curricula -- South Africa -- Eastern Cape Environmental education -- Curricula -- Case studies Environmental policy -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1487 , http://hdl.handle.net/10962/d1003368
- Description: With a view to understanding how curriculum is interpreted at classroom practice level, the study examined three stories of how the environmental discourse of the National Curriculum Statements (R-9) was recontextualised using school gardens in the Life Orientation Learning Area for the Senior Phase. To understand how the curriculum is recontextualised, I used Bernstein's theory of recontexutalisation where he explained how official pedagogic discourse (OPD) (in this case the environmental discourse is first delocated once it is transferred from the field of production (FOP) and relocated in the recontextualising field (where teacher educators and departmental officials mediate the discourse) and in the field of reproduction (FOR) which is the classroom and school. Bernstein explained that as the discourse is delocated and relocated it undergoes transformation. This transformation is influenced by practitioners' prior-knowledge, experience, culture and beliefs and other factors. To understand how transformation of the environmental discourse takes place, Bernstein's conceptual constructs of selective appropriation and ideological transformation were applied to an interpretation of three lesson processes, to explain how the discourse was changed. Each lesson was reviewed in terms of the selective appropriations and ideological transformations which took place. All three of the lessons observed took place in one school, and as such the study is designed as an interpretive case study where I have tried to make meaning from a rich, thick description of a specific case context. The school is located in Bizana, one of the villages in the O.R. Tambo District Municipality in the Eastern Cape Province,, and is currently in the process of implementing South Africa’s new National Curriculum Statement (NCS) like all other schools in South Africa. In conducting the research I observed lessons, interviewed the learners and teachers, and a community member and the manager of the SANBI greening project, and I also analysed documents which included the NCS for Life Orientation, and teachers planning documents and learners work produced in the lessons. I started the study by conducting a document analysis of the NCS, through which I identified dimensions of the Official Pedagogic Discourse. This was used as a framework to review the lessons to understand how the OPD was being recontextualised. The study concludes by discussing the key findings of the study in the form of a set of analytical statements. Some of the findings indicate that teachers have not been given adequate training for understanding and implementing the NCS which affects the recontextualisation process. The study shows that there is a dire need for professional development if the OPD is to be interpreted adequately by teachers so that its implementation at the meso and micro- levels becomes clear and effective.
- Full Text:
- Date Issued: 2008
- Authors: Jenkins, Msawenkosi Wiseman
- Date: 2008
- Subjects: Environmental education -- South Africa -- Eastern Cape -- Case studies School gardens -- South Africa -- Eastern Cape Gardening -- Study and teaching (Secondary) -- South Africa -- Eastern Cape Environmental education -- Curricula -- South Africa -- Eastern Cape Environmental education -- Curricula -- Case studies Environmental policy -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1487 , http://hdl.handle.net/10962/d1003368
- Description: With a view to understanding how curriculum is interpreted at classroom practice level, the study examined three stories of how the environmental discourse of the National Curriculum Statements (R-9) was recontextualised using school gardens in the Life Orientation Learning Area for the Senior Phase. To understand how the curriculum is recontextualised, I used Bernstein's theory of recontexutalisation where he explained how official pedagogic discourse (OPD) (in this case the environmental discourse is first delocated once it is transferred from the field of production (FOP) and relocated in the recontextualising field (where teacher educators and departmental officials mediate the discourse) and in the field of reproduction (FOR) which is the classroom and school. Bernstein explained that as the discourse is delocated and relocated it undergoes transformation. This transformation is influenced by practitioners' prior-knowledge, experience, culture and beliefs and other factors. To understand how transformation of the environmental discourse takes place, Bernstein's conceptual constructs of selective appropriation and ideological transformation were applied to an interpretation of three lesson processes, to explain how the discourse was changed. Each lesson was reviewed in terms of the selective appropriations and ideological transformations which took place. All three of the lessons observed took place in one school, and as such the study is designed as an interpretive case study where I have tried to make meaning from a rich, thick description of a specific case context. The school is located in Bizana, one of the villages in the O.R. Tambo District Municipality in the Eastern Cape Province,, and is currently in the process of implementing South Africa’s new National Curriculum Statement (NCS) like all other schools in South Africa. In conducting the research I observed lessons, interviewed the learners and teachers, and a community member and the manager of the SANBI greening project, and I also analysed documents which included the NCS for Life Orientation, and teachers planning documents and learners work produced in the lessons. I started the study by conducting a document analysis of the NCS, through which I identified dimensions of the Official Pedagogic Discourse. This was used as a framework to review the lessons to understand how the OPD was being recontextualised. The study concludes by discussing the key findings of the study in the form of a set of analytical statements. Some of the findings indicate that teachers have not been given adequate training for understanding and implementing the NCS which affects the recontextualisation process. The study shows that there is a dire need for professional development if the OPD is to be interpreted adequately by teachers so that its implementation at the meso and micro- levels becomes clear and effective.
- Full Text:
- Date Issued: 2008
Customer relations management in SMMEs: an integrated approach
- Authors: Sandekela, Lindela Prince
- Date: 2008
- Subjects: Customer relations -- Management , Small business -- South Africa -- Management , Customer services
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8725 , http://hdl.handle.net/10948/889 , Customer relations -- Management , Small business -- South Africa -- Management , Customer services
- Description: The research study was conducted to cover the Buffalo City Municipality (BCM) retail industry with direct emphasis on the supermarket industry. The research problem is as a result of the retail businesses in the BCM that continue to consider that if they have large data warehouses with masses of customer information, they have all what it takes to run a profitable business. Their failure to understand the organizational implications of moving towards a customer-centric approach often results in high costs from bad customer service and handling of customer complaints. The main problem was stated and sub-problems introduced from the main problem to address them by way of qualitative and quantitative research. Related literature was reviewed on Redefining the Customer, Customer Satisfaction and Customer Relationship Management and a Customer Management Model was proposed. During empirical survey, a questionnaire based on literature reviewed was designed for the survey. A pilot study was conducted to identify and rectify problems and shortcomings relating to the questionnaire. The pilot study indicated that the data likely to be collected will address the main and sub-problems of the research. A total of thirty five questionnaires which contained closed-ended and open-ended questions were distributed to the population sample as selected. Results of the study were critically analysed and interpreted quantitatively and qualitatively by means of tables and discussion for the development of an Integrated Model for managing customers. The analysis of the study which was based on the literature reviewed and the findings from the empirical survey were concluded to present a solution to the problem. In view of the shortcomings identified by the literature review and integration thereof with the results of the empirical study, an Integrated Customer Management Model was developed.
- Full Text:
- Date Issued: 2008
- Authors: Sandekela, Lindela Prince
- Date: 2008
- Subjects: Customer relations -- Management , Small business -- South Africa -- Management , Customer services
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8725 , http://hdl.handle.net/10948/889 , Customer relations -- Management , Small business -- South Africa -- Management , Customer services
- Description: The research study was conducted to cover the Buffalo City Municipality (BCM) retail industry with direct emphasis on the supermarket industry. The research problem is as a result of the retail businesses in the BCM that continue to consider that if they have large data warehouses with masses of customer information, they have all what it takes to run a profitable business. Their failure to understand the organizational implications of moving towards a customer-centric approach often results in high costs from bad customer service and handling of customer complaints. The main problem was stated and sub-problems introduced from the main problem to address them by way of qualitative and quantitative research. Related literature was reviewed on Redefining the Customer, Customer Satisfaction and Customer Relationship Management and a Customer Management Model was proposed. During empirical survey, a questionnaire based on literature reviewed was designed for the survey. A pilot study was conducted to identify and rectify problems and shortcomings relating to the questionnaire. The pilot study indicated that the data likely to be collected will address the main and sub-problems of the research. A total of thirty five questionnaires which contained closed-ended and open-ended questions were distributed to the population sample as selected. Results of the study were critically analysed and interpreted quantitatively and qualitatively by means of tables and discussion for the development of an Integrated Model for managing customers. The analysis of the study which was based on the literature reviewed and the findings from the empirical survey were concluded to present a solution to the problem. In view of the shortcomings identified by the literature review and integration thereof with the results of the empirical study, an Integrated Customer Management Model was developed.
- Full Text:
- Date Issued: 2008
Depressogenic cognitive schemas, levels of depression and hopelessness among individuals diagnosed with unipolar mood disorder
- Authors: Du Preez, Shereen
- Date: 2008
- Subjects: Neuropsychiatry , Depression, Mental -- South Africa , Depressed persons -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9899 , http://hdl.handle.net/10948/1074 , Neuropsychiatry , Depression, Mental -- South Africa , Depressed persons -- South Africa
- Description: While mood disorders rank within the top ten disabilities worldwide, there has been limited research done on cognitive schemas and the role they play in the development of mood disorders in South Africa. Cognitive conceptualisations of depression typically emphasize the schema-based automatic processing of information. Beck (1967, 1976 & 1987) suggested that schematically driven automatic thinking is a key element in depressive disorders. Research in the field of depression has identified cognitive schemas as a factor which increases an individual’s diathesis to depression. The primary aim of this research is to explore and describe maladaptive cognitive schemas, hopelessness and levels of depression amongst individuals diagnosed with Unipolar Mood Disorder. A further aim of the research has been to explore the relationship between maladaptive cognitive schemas and hopelessness as a diathesis to depression. In order to achieve the objectives, data was collected from a sample of 50 inpatients diagnosed with Unipolar Mood Disorder. The following measures were used: Young’s Schema Questionnaire, Beck's Depression Inventory – 2nd edition and Beck’s Hopelessness Scale. The research is quantitative in nature and takes the form of an exploratory-descriptive study. Data has been analysed by means of descriptive statistics in order to identify the mean, ranges and standard deviation of the measures used. Cross-tabulations have been used to further explore the relationship between the variables mentioned above. It was found that a statistically significant correlation exists between the BDI, BHS and YSQ. Maladaptive cognitive schemas were found to have a strong positive correlation 4 to depression, whereas hopelessness was found to have a less significant role in Unipolar Mood Disorder. The most significant schemas found in relation to hopelessness, were the Social Isolation, Unrelenting Standards and Pessimism schemas. With regards to depression, the most significant schemas were found to be Mistrust, Practical Incompetence, Vulnerability, Subjugation, Self-Sacrifice, Emotional Inhibition, Unrelenting Standards, Entitlement, Insufficient Self-Control, Admiration, Pessimism and Self-Punitiveness. All the above mentioned variables proved to have a statistically significant relationship. The findings of this research study are for the most part consistent with the literature on depression, hopelessness and cognitive vulnerabilities, and all of the above mentioned concepts have been found to be related.
- Full Text:
- Date Issued: 2008
- Authors: Du Preez, Shereen
- Date: 2008
- Subjects: Neuropsychiatry , Depression, Mental -- South Africa , Depressed persons -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9899 , http://hdl.handle.net/10948/1074 , Neuropsychiatry , Depression, Mental -- South Africa , Depressed persons -- South Africa
- Description: While mood disorders rank within the top ten disabilities worldwide, there has been limited research done on cognitive schemas and the role they play in the development of mood disorders in South Africa. Cognitive conceptualisations of depression typically emphasize the schema-based automatic processing of information. Beck (1967, 1976 & 1987) suggested that schematically driven automatic thinking is a key element in depressive disorders. Research in the field of depression has identified cognitive schemas as a factor which increases an individual’s diathesis to depression. The primary aim of this research is to explore and describe maladaptive cognitive schemas, hopelessness and levels of depression amongst individuals diagnosed with Unipolar Mood Disorder. A further aim of the research has been to explore the relationship between maladaptive cognitive schemas and hopelessness as a diathesis to depression. In order to achieve the objectives, data was collected from a sample of 50 inpatients diagnosed with Unipolar Mood Disorder. The following measures were used: Young’s Schema Questionnaire, Beck's Depression Inventory – 2nd edition and Beck’s Hopelessness Scale. The research is quantitative in nature and takes the form of an exploratory-descriptive study. Data has been analysed by means of descriptive statistics in order to identify the mean, ranges and standard deviation of the measures used. Cross-tabulations have been used to further explore the relationship between the variables mentioned above. It was found that a statistically significant correlation exists between the BDI, BHS and YSQ. Maladaptive cognitive schemas were found to have a strong positive correlation 4 to depression, whereas hopelessness was found to have a less significant role in Unipolar Mood Disorder. The most significant schemas found in relation to hopelessness, were the Social Isolation, Unrelenting Standards and Pessimism schemas. With regards to depression, the most significant schemas were found to be Mistrust, Practical Incompetence, Vulnerability, Subjugation, Self-Sacrifice, Emotional Inhibition, Unrelenting Standards, Entitlement, Insufficient Self-Control, Admiration, Pessimism and Self-Punitiveness. All the above mentioned variables proved to have a statistically significant relationship. The findings of this research study are for the most part consistent with the literature on depression, hopelessness and cognitive vulnerabilities, and all of the above mentioned concepts have been found to be related.
- Full Text:
- Date Issued: 2008
Designing accessible portals in South Africa: a case study
- Authors: Meyer, Shaun
- Date: 2008
- Subjects: Web portals -- South Africa -- Port Elizabeth , Web site development -- South Africa -- Port Elizabeth , Internet programming , Web sites -- Design
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9782 , http://hdl.handle.net/10948/770 , Web portals -- South Africa -- Port Elizabeth , Web site development -- South Africa -- Port Elizabeth , Internet programming , Web sites -- Design
- Description: Web portals are considered “gateways” to the World Wide Web. These portals are becoming very popular entry points to the Web by offering important services such as email, news, weather reports, course notes and general information. In addition, some portal sites allow users the option of customising the site according to their personal interests. However, disabled and elderly people encounter many accessibility and usability barriers while accessing web portals. A preliminary review of a university portal was conducted to identify some of these accessibility problems. This treatise presents an overview of the processes to be followed when conducting an accessibility and usability evaluation. In addition, it mentions some guidelines to be considered when specifically designing portals for use by many different users from varying backgrounds.
- Full Text:
- Date Issued: 2008
- Authors: Meyer, Shaun
- Date: 2008
- Subjects: Web portals -- South Africa -- Port Elizabeth , Web site development -- South Africa -- Port Elizabeth , Internet programming , Web sites -- Design
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9782 , http://hdl.handle.net/10948/770 , Web portals -- South Africa -- Port Elizabeth , Web site development -- South Africa -- Port Elizabeth , Internet programming , Web sites -- Design
- Description: Web portals are considered “gateways” to the World Wide Web. These portals are becoming very popular entry points to the Web by offering important services such as email, news, weather reports, course notes and general information. In addition, some portal sites allow users the option of customising the site according to their personal interests. However, disabled and elderly people encounter many accessibility and usability barriers while accessing web portals. A preliminary review of a university portal was conducted to identify some of these accessibility problems. This treatise presents an overview of the processes to be followed when conducting an accessibility and usability evaluation. In addition, it mentions some guidelines to be considered when specifically designing portals for use by many different users from varying backgrounds.
- Full Text:
- Date Issued: 2008
Designing and implementing a new pulsar timer for the Hartebeesthoek Radio Astronomy Observatory
- Authors: Youthed, Andrew David
- Date: 2008
- Subjects: Astronomical observatories , Radio astronomy , Pulsars , Astronomical instruments , Reduced instruction set computers , Random access memory
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5458 , http://hdl.handle.net/10962/d1005243 , Astronomical observatories , Radio astronomy , Pulsars , Astronomical instruments , Reduced instruction set computers , Random access memory
- Description: This thesis outlines the design and implementation of a single channel, dual polarization pulsar timing instrument for the Hartebeesthoek Radio Astronomy Observatory (HartRAO). The new timer is designed to be an improved, temporary replacement for the existing device which has been in operation for over 20 years. The existing device is no longer reliable and is di±cult to maintain. The new pulsar timer is designed to provide improved functional- ity, higher sampling speed, greater pulse resolution, more °exibility and easier maintenance over the existing device. The new device is also designed to keeping changes to the observation system to a minimum until a full de-dispersion timer can be implemented at theobservatory. The design makes use of an 8-bit Reduced Instruction Set Computer (RISC) micro-processor with external Random Access Memory (RAM). The instrument includes an IEEE-488 subsystem for interfacing the pulsar timer to the observation computer system. The microcontroller software is written in assembler code to ensure optimal loop execution speed and deterministic code execution for the system. The design path is discussed and problems encountered during the design process are highlighted. Final testing of the new instrument indicates an improvement in the sam- pling rate of 13.6 times and a significant reduction in 60Hz interference over the existing instrument.
- Full Text:
- Date Issued: 2008
- Authors: Youthed, Andrew David
- Date: 2008
- Subjects: Astronomical observatories , Radio astronomy , Pulsars , Astronomical instruments , Reduced instruction set computers , Random access memory
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5458 , http://hdl.handle.net/10962/d1005243 , Astronomical observatories , Radio astronomy , Pulsars , Astronomical instruments , Reduced instruction set computers , Random access memory
- Description: This thesis outlines the design and implementation of a single channel, dual polarization pulsar timing instrument for the Hartebeesthoek Radio Astronomy Observatory (HartRAO). The new timer is designed to be an improved, temporary replacement for the existing device which has been in operation for over 20 years. The existing device is no longer reliable and is di±cult to maintain. The new pulsar timer is designed to provide improved functional- ity, higher sampling speed, greater pulse resolution, more °exibility and easier maintenance over the existing device. The new device is also designed to keeping changes to the observation system to a minimum until a full de-dispersion timer can be implemented at theobservatory. The design makes use of an 8-bit Reduced Instruction Set Computer (RISC) micro-processor with external Random Access Memory (RAM). The instrument includes an IEEE-488 subsystem for interfacing the pulsar timer to the observation computer system. The microcontroller software is written in assembler code to ensure optimal loop execution speed and deterministic code execution for the system. The design path is discussed and problems encountered during the design process are highlighted. Final testing of the new instrument indicates an improvement in the sam- pling rate of 13.6 times and a significant reduction in 60Hz interference over the existing instrument.
- Full Text:
- Date Issued: 2008
Determinants of household food security in the semi-arid areas of Zimbabwe: a case study of irrigation and non-irrigation farmers in Lupane and Hwange districts
- Authors: Sikwela, Misery Mpuzu
- Date: 2008
- Subjects: Food -- Safety measures , Irrigation farming -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11163 , http://hdl.handle.net/10353/90 , Food -- Safety measures , Irrigation farming -- Zimbabwe
- Description: Lupane and Hwange districts fall under natural region IV and V and lie in the semi-arid regions of Zimbabwe with low and erratic mean annual rainfall not exceeding 600mm. Seventy percent of Zimbabwe’s population lives in communal areas, whose livelihood is based on agriculture. The communities in these areas mainly practice mixed farming systems. However, crop production is constrained by water availability and suitable production techniques. As a result households in these areas are experiencing worsening levels of household food insecurity. Two irrigation schemes were identified for this study and these are located in these two districts. Tshongokwe irrigation scheme is located in Lupane district and Lukosi irrigation scheme is located in Hwange district and these irrigation schemes are about 25 hectares in size. Lupane and Hwange districts are considered to be one of the most food insecure areas in the country because of the frequent droughts and unreliable rainfall in the region. The major tool of enquiry in this study was the questionnaire which was used to collect data from the households that farm on irrigated land and those that farm on dryland farming. Household and farm characteristics were collected using structured questionnaires with the help of locally recruited and trained enumerators. Agricultural production, household consumption and marketing of agricultural produce were accessed using the questionnaire to establish problems experienced by farmers. The main objective of this study was to investigate the determinants of household food security using a logistic regression model. The model was initially fitted with thirteen variables, selected from factors identified by previous researchers that affect food security in communal areas. Six variables were found to be significant at 1, 5 and 10 percent significance level and all had the expected signs except farm size. These factors include access to irrigation, farm size, cattle ownership, fertilizer application, household size and per capita aggregate production. The results obtained were further analyzed to compute partial effects on continuous variables and change in probabilities on the discrete variables for the significant factors in the logistic regression model. Analysis of partial effects revealed that household size, farm size, cattle ownership and per capita aggregate production lead to a greater probability of household being food secure. Change in probability results showed that having access to irrigation and using fertilizer can increase the probability of household being food secure The findings of this study highlight a positive and significant relationship between access to irrigation, fertilizer application, cattle ownership, per capita aggregate production to household food security. Household size and farm size have a negative and significant relationship on household food security. This study shows the effectiveness of irrigated farming over dryland farming in the semi-arid areas. The results show increased agricultural production, crop diversification and higher incomes from irrigation farming as compared to dry land farming. Irrigation farming has enabled many households to diversify their source of income and generate more income. Irrigation has enabled households with irrigation not only to feed themselves throughout the year but also to invest on non-agricultural goods and services from incomes received from crop sales Based on the results from the logistic regression model, it can be concluded that household size, farm size, per capita aggregate production, cattle ownership, fertilizer application and access to irrigation have a positive effect on household food security and the magnitude of changes in conditional probabilities have an impact on household food security.
- Full Text:
- Date Issued: 2008
- Authors: Sikwela, Misery Mpuzu
- Date: 2008
- Subjects: Food -- Safety measures , Irrigation farming -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11163 , http://hdl.handle.net/10353/90 , Food -- Safety measures , Irrigation farming -- Zimbabwe
- Description: Lupane and Hwange districts fall under natural region IV and V and lie in the semi-arid regions of Zimbabwe with low and erratic mean annual rainfall not exceeding 600mm. Seventy percent of Zimbabwe’s population lives in communal areas, whose livelihood is based on agriculture. The communities in these areas mainly practice mixed farming systems. However, crop production is constrained by water availability and suitable production techniques. As a result households in these areas are experiencing worsening levels of household food insecurity. Two irrigation schemes were identified for this study and these are located in these two districts. Tshongokwe irrigation scheme is located in Lupane district and Lukosi irrigation scheme is located in Hwange district and these irrigation schemes are about 25 hectares in size. Lupane and Hwange districts are considered to be one of the most food insecure areas in the country because of the frequent droughts and unreliable rainfall in the region. The major tool of enquiry in this study was the questionnaire which was used to collect data from the households that farm on irrigated land and those that farm on dryland farming. Household and farm characteristics were collected using structured questionnaires with the help of locally recruited and trained enumerators. Agricultural production, household consumption and marketing of agricultural produce were accessed using the questionnaire to establish problems experienced by farmers. The main objective of this study was to investigate the determinants of household food security using a logistic regression model. The model was initially fitted with thirteen variables, selected from factors identified by previous researchers that affect food security in communal areas. Six variables were found to be significant at 1, 5 and 10 percent significance level and all had the expected signs except farm size. These factors include access to irrigation, farm size, cattle ownership, fertilizer application, household size and per capita aggregate production. The results obtained were further analyzed to compute partial effects on continuous variables and change in probabilities on the discrete variables for the significant factors in the logistic regression model. Analysis of partial effects revealed that household size, farm size, cattle ownership and per capita aggregate production lead to a greater probability of household being food secure. Change in probability results showed that having access to irrigation and using fertilizer can increase the probability of household being food secure The findings of this study highlight a positive and significant relationship between access to irrigation, fertilizer application, cattle ownership, per capita aggregate production to household food security. Household size and farm size have a negative and significant relationship on household food security. This study shows the effectiveness of irrigated farming over dryland farming in the semi-arid areas. The results show increased agricultural production, crop diversification and higher incomes from irrigation farming as compared to dry land farming. Irrigation farming has enabled many households to diversify their source of income and generate more income. Irrigation has enabled households with irrigation not only to feed themselves throughout the year but also to invest on non-agricultural goods and services from incomes received from crop sales Based on the results from the logistic regression model, it can be concluded that household size, farm size, per capita aggregate production, cattle ownership, fertilizer application and access to irrigation have a positive effect on household food security and the magnitude of changes in conditional probabilities have an impact on household food security.
- Full Text:
- Date Issued: 2008
Determination and validation of ethno-veterinary practices used as alternatives in controlling cattle ticks by resource-limited farmers in the Eastern Cape Province, South Africa
- Authors: Moyo, Busani
- Date: 2008
- Subjects: Traditional veterinary medicine -- South Africa -- Eastern Cape Province , Ethnozoology -- South Africa -- Eastern Cape Province , Ticks -- South Africa -- Eastern Cape Province
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11806 , http://hdl.handle.net/10353/165 , Traditional veterinary medicine -- South Africa -- Eastern Cape Province , Ethnozoology -- South Africa -- Eastern Cape Province , Ticks -- South Africa -- Eastern Cape Province
- Description: Ticks are the most common external parasites of economic importance in the livestock farming sector of Southern Africa. They are vectors of tick-borne diseases and are commonly controlled using conventional acaricides, which are expensive and not readily available to resource-limited farmers. As a result many resource-limited farmers resort to use of alternative materials to control ticks on their livestock. Tick resistance to acaricide is an increasing problem in Southern Africa and poses a real economic threat to livestock and veterinary pharmaceutical industries. The objective of this study was to document and validate the ethno-veterinary remedies used as alternative methods of controlling cattle ticks by resource-limited farmers. A questionnaire survey was conducted in May 2007, at Qolora by-Sea and Nontshinga in Centane district, to determine tick control methods used by resource limited farmers in the Amathole District Municipality of the Eastern Cape Province, South Africa. Furthermore, in vitro and in vivo experiments were done to validate the acaricidal properties of ethnoveterinary remedies used by resource-limited farmers. Ticks were reported to be a major problem, transmitting diseases like anaplasmosis (89.8%), babesiosis (55.9%) and ehrlichiosis (16.9%), they also cause wounds that predispose cattle to screwworm infestation, tick worry and teat damage. All farmers used acaricides and dipping tanks provided by the government to control ticks, as the main tick control method. However, the majority (94.9%) were of the opinion that the dip wash was not effective in controlling ticks. As a result, farmers complemented the government dipping service with use of own initiatives like spraying with conventional acaricides (22%), household disinfectants such as Jeyes fluid (18.6%), used engine oil (10.2%), chickens feeding on ticks (5.1%), manual iv removal (5.1%), and pouricides (1.7%). In addition, some farmers also use plants (6.8%), mainly the leaf of Aloe ferox and the bark of Ptaeroxylon obliquum. The in vitro repellency models showed Jeyes fluid (76.8 and 100% concentrations) and P. obliquum (40%) had repellent properties that lasted 6 hours and 40 minutes respectively while that of, Tabard (35% diethyltoluamide) positive control, lasted for 4 hours when applied against nymphal stages of Rhipicephalus sanguineus ticks. In the contact bio-assay, undiluted used engine oil, T. minuta oil (50%), Ektoban® (Cymiazol 17.5% and cypermethrin 2.5%) and Jeyes fluid (76.8%) caused higher tick mortality of more than 86%. Other materials (A. ferox, Lantana camara and Tagetes minuta) had no repellence and acaricidal properties. In the in vivo study, Jeyes fluid at a concentration of 76.8% and used engine oil displayed efficacy of 71 and 76.4% respectively which was similar to that of the positive control Ektoban® at 97.8% tick load reduction. Among plant materials L. camara at 40% concentrations had an efficacy of 57% while A. ferox, P. obliquum and T. minuta were not effective at all. The remedies used by resource-limited farmers to control ticks vary in efficacy. Their ability to reduce tick load on cattle appears to be promising and a welcome development as their use could probably reduce tick burdens in cattle with less expenditure. However, further investigations need to be done before they are recommended for use. Despite being effective some of the materials have potential toxic effects in animals and also cause environmental contamination and I recommend used engine oil, Jeyes fluid and L. camara for further testing as they showed some efficacy compared to other remedies.
- Full Text:
- Date Issued: 2008
- Authors: Moyo, Busani
- Date: 2008
- Subjects: Traditional veterinary medicine -- South Africa -- Eastern Cape Province , Ethnozoology -- South Africa -- Eastern Cape Province , Ticks -- South Africa -- Eastern Cape Province
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11806 , http://hdl.handle.net/10353/165 , Traditional veterinary medicine -- South Africa -- Eastern Cape Province , Ethnozoology -- South Africa -- Eastern Cape Province , Ticks -- South Africa -- Eastern Cape Province
- Description: Ticks are the most common external parasites of economic importance in the livestock farming sector of Southern Africa. They are vectors of tick-borne diseases and are commonly controlled using conventional acaricides, which are expensive and not readily available to resource-limited farmers. As a result many resource-limited farmers resort to use of alternative materials to control ticks on their livestock. Tick resistance to acaricide is an increasing problem in Southern Africa and poses a real economic threat to livestock and veterinary pharmaceutical industries. The objective of this study was to document and validate the ethno-veterinary remedies used as alternative methods of controlling cattle ticks by resource-limited farmers. A questionnaire survey was conducted in May 2007, at Qolora by-Sea and Nontshinga in Centane district, to determine tick control methods used by resource limited farmers in the Amathole District Municipality of the Eastern Cape Province, South Africa. Furthermore, in vitro and in vivo experiments were done to validate the acaricidal properties of ethnoveterinary remedies used by resource-limited farmers. Ticks were reported to be a major problem, transmitting diseases like anaplasmosis (89.8%), babesiosis (55.9%) and ehrlichiosis (16.9%), they also cause wounds that predispose cattle to screwworm infestation, tick worry and teat damage. All farmers used acaricides and dipping tanks provided by the government to control ticks, as the main tick control method. However, the majority (94.9%) were of the opinion that the dip wash was not effective in controlling ticks. As a result, farmers complemented the government dipping service with use of own initiatives like spraying with conventional acaricides (22%), household disinfectants such as Jeyes fluid (18.6%), used engine oil (10.2%), chickens feeding on ticks (5.1%), manual iv removal (5.1%), and pouricides (1.7%). In addition, some farmers also use plants (6.8%), mainly the leaf of Aloe ferox and the bark of Ptaeroxylon obliquum. The in vitro repellency models showed Jeyes fluid (76.8 and 100% concentrations) and P. obliquum (40%) had repellent properties that lasted 6 hours and 40 minutes respectively while that of, Tabard (35% diethyltoluamide) positive control, lasted for 4 hours when applied against nymphal stages of Rhipicephalus sanguineus ticks. In the contact bio-assay, undiluted used engine oil, T. minuta oil (50%), Ektoban® (Cymiazol 17.5% and cypermethrin 2.5%) and Jeyes fluid (76.8%) caused higher tick mortality of more than 86%. Other materials (A. ferox, Lantana camara and Tagetes minuta) had no repellence and acaricidal properties. In the in vivo study, Jeyes fluid at a concentration of 76.8% and used engine oil displayed efficacy of 71 and 76.4% respectively which was similar to that of the positive control Ektoban® at 97.8% tick load reduction. Among plant materials L. camara at 40% concentrations had an efficacy of 57% while A. ferox, P. obliquum and T. minuta were not effective at all. The remedies used by resource-limited farmers to control ticks vary in efficacy. Their ability to reduce tick load on cattle appears to be promising and a welcome development as their use could probably reduce tick burdens in cattle with less expenditure. However, further investigations need to be done before they are recommended for use. Despite being effective some of the materials have potential toxic effects in animals and also cause environmental contamination and I recommend used engine oil, Jeyes fluid and L. camara for further testing as they showed some efficacy compared to other remedies.
- Full Text:
- Date Issued: 2008
Developing a business model for a community radio station in Port Elizabeth: a case study
- Ngcezula, Anthony Thamsanqa "Delite"
- Authors: Ngcezula, Anthony Thamsanqa "Delite"
- Date: 2008
- Subjects: Radio in community development , Radio broadcasting -- South Africa , Community radio
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8720 , http://hdl.handle.net/10948/906 , Radio in community development , Radio broadcasting -- South Africa , Community radio
- Description: The purpose of this treatise is a development of a suitable model for a community radio station which would lead to operational effectiveness and ensure sustainability. The treatise has three phases namely a theoretical phase, a narration phase and an integration phase. Firstly, in the theoretical phase the research study investigates what the literature review reveals about community radio stations and business models. This treatise argues that a total dependency of community radio stations on donor funding leads to operational ineffectiveness which threatens their sustainability. The treatise also argues that a business model could be adapted for a community radio station by identifying the business issues which the literature review revealed, and use these to deconstruct a theoretical business model. Secondly, in the narrative phase the research study investigates the important business issues for a selected community radio station. The treatise argues the board and management of this selected community radio station revealed additional business issues of operations and gave different ratings to business issues which are important in their operations. Thirdly, in the integration phase, the theoretical model deconstructed in the theoretical phase, was revised by including additional business issues of operations revealed in the narrative phase. The research study concludes that this revised model is a suitable business model for a community radio station and can lead to operational effectiveness and ensure sustainability.
- Full Text:
- Date Issued: 2008
- Authors: Ngcezula, Anthony Thamsanqa "Delite"
- Date: 2008
- Subjects: Radio in community development , Radio broadcasting -- South Africa , Community radio
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8720 , http://hdl.handle.net/10948/906 , Radio in community development , Radio broadcasting -- South Africa , Community radio
- Description: The purpose of this treatise is a development of a suitable model for a community radio station which would lead to operational effectiveness and ensure sustainability. The treatise has three phases namely a theoretical phase, a narration phase and an integration phase. Firstly, in the theoretical phase the research study investigates what the literature review reveals about community radio stations and business models. This treatise argues that a total dependency of community radio stations on donor funding leads to operational ineffectiveness which threatens their sustainability. The treatise also argues that a business model could be adapted for a community radio station by identifying the business issues which the literature review revealed, and use these to deconstruct a theoretical business model. Secondly, in the narrative phase the research study investigates the important business issues for a selected community radio station. The treatise argues the board and management of this selected community radio station revealed additional business issues of operations and gave different ratings to business issues which are important in their operations. Thirdly, in the integration phase, the theoretical model deconstructed in the theoretical phase, was revised by including additional business issues of operations revealed in the narrative phase. The research study concludes that this revised model is a suitable business model for a community radio station and can lead to operational effectiveness and ensure sustainability.
- Full Text:
- Date Issued: 2008
Developing a long-term strategy for a selected small transport entrepreneur
- Authors: Burgins, David Christopher
- Date: 2008
- Subjects: Transportation -- South Africa -- Port Elizabeth -- Planning , Transportation and state -- South Africa -- Port Elizabeth , Transportation -- South Africa -- Port Elizabeth -- Finance
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8714 , http://hdl.handle.net/10948/929 , Transportation -- South Africa -- Port Elizabeth -- Planning , Transportation and state -- South Africa -- Port Elizabeth , Transportation -- South Africa -- Port Elizabeth -- Finance
- Description: South Africa, recognised as a developing economy, is encouraging its citizens to be entrepreneurs through various initiatives and assistance, with a bias towards the previously disadvantage people. This encouragement, from the government, has been taken advantage of by numerous citizens to the detriment of themselves, especially in the transport industry. Kazderich Pro Trans, a small transport entrepreneur, has founded itself based on the notion that businesses will utilize its services frequently based on the preferential treatment, to previously disadvantaged communities. The stakeholders in the transport industry, however is firstly geared towards maintaining their market share in a fiercely competitive industry with arguably an introspective view of the preferential treatment governmental policies. The purpose of this is to research the transport industry and accurately identify the environment the transport businesses operate in, with a view of analysing competencies that attract and retain business. This paper negates the government policy to a minor external environmental factor and argues that the company (Kazderich Pro Trans) should operate on the same principals as its competitors in the transport industry. The important issue being discussed in this research, the long term strategy, is to make small transport entrepreneurs realise that researching and planning their business are more important than starting it. The attraction and retention of clients is the basis of a successful transport business and the analyses of the questionnaire employed are used as guidance in developing the long term strategy.
- Full Text:
- Date Issued: 2008
- Authors: Burgins, David Christopher
- Date: 2008
- Subjects: Transportation -- South Africa -- Port Elizabeth -- Planning , Transportation and state -- South Africa -- Port Elizabeth , Transportation -- South Africa -- Port Elizabeth -- Finance
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8714 , http://hdl.handle.net/10948/929 , Transportation -- South Africa -- Port Elizabeth -- Planning , Transportation and state -- South Africa -- Port Elizabeth , Transportation -- South Africa -- Port Elizabeth -- Finance
- Description: South Africa, recognised as a developing economy, is encouraging its citizens to be entrepreneurs through various initiatives and assistance, with a bias towards the previously disadvantage people. This encouragement, from the government, has been taken advantage of by numerous citizens to the detriment of themselves, especially in the transport industry. Kazderich Pro Trans, a small transport entrepreneur, has founded itself based on the notion that businesses will utilize its services frequently based on the preferential treatment, to previously disadvantaged communities. The stakeholders in the transport industry, however is firstly geared towards maintaining their market share in a fiercely competitive industry with arguably an introspective view of the preferential treatment governmental policies. The purpose of this is to research the transport industry and accurately identify the environment the transport businesses operate in, with a view of analysing competencies that attract and retain business. This paper negates the government policy to a minor external environmental factor and argues that the company (Kazderich Pro Trans) should operate on the same principals as its competitors in the transport industry. The important issue being discussed in this research, the long term strategy, is to make small transport entrepreneurs realise that researching and planning their business are more important than starting it. The attraction and retention of clients is the basis of a successful transport business and the analyses of the questionnaire employed are used as guidance in developing the long term strategy.
- Full Text:
- Date Issued: 2008
Development of an integration model for the transport operators in the Nelson Mandela Bay area
- Authors: Pienaar, Jacques Ludolph
- Date: 2008
- Subjects: Urban transportation -- South Africa -- Port Elizabeth , Transportation -- South Africa -- Port Elizabeth -- Planning
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8722 , http://hdl.handle.net/10948/900 , Urban transportation -- South Africa -- Port Elizabeth , Transportation -- South Africa -- Port Elizabeth -- Planning
- Description: This research paper focuses on developing a model for the integration of the transport operators in the Nelson Mandela Bay area. The motivation for this integration is the Nelson Mandela Bay Municipality’s Public Transport Plan, which has set the goal of developing a new public transport system for the Metropolitan area. This system will integrate the different modes of transport into a single, seamless and scheduled service which will adhere to contractually enforced levels of quality, reliability and safety. In order to achieve this vision, the current bus and taxi operators will need to be unified into a viable and operational entity structure which will provide the required services to the public. The main research problem has therefore been identified as follows: How can the bus and taxi operators in Nelson Mandela Bay be integrated into a single entity, or small number of entities, in order to provide a viable, efficient and sustainable public transport service? This research paper sought to address this problem by conducting a case study of the Nelson Mandela Bay project, which took place over the course of a one year period. The author served as the project manager on the team that was responsible for developing the integration model. Additional research included a study visit to the cities of Bogota and Pereira in Colombia, which have implemented similar transport models, as well as a secondary study focusing on generic organisational integration strategies in existing literature. This paper is fundamentally a qualitative study. In this light, the research data was analysed according to the quasi-judicial method, which was deemed most suitable to the case study format adopted. The findings of the analysis were evaluated, and based on the resultant conclusions, a final integration model was recommended. The fact that this study is based on an actual project that has real world implications and consequences makes the result very relevant, and as such it will serve as a valuable addition to the body of knowledge which can be of assistance to other cities or project teams facing similar challenges in South Africa or even internationally.
- Full Text:
- Date Issued: 2008
- Authors: Pienaar, Jacques Ludolph
- Date: 2008
- Subjects: Urban transportation -- South Africa -- Port Elizabeth , Transportation -- South Africa -- Port Elizabeth -- Planning
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8722 , http://hdl.handle.net/10948/900 , Urban transportation -- South Africa -- Port Elizabeth , Transportation -- South Africa -- Port Elizabeth -- Planning
- Description: This research paper focuses on developing a model for the integration of the transport operators in the Nelson Mandela Bay area. The motivation for this integration is the Nelson Mandela Bay Municipality’s Public Transport Plan, which has set the goal of developing a new public transport system for the Metropolitan area. This system will integrate the different modes of transport into a single, seamless and scheduled service which will adhere to contractually enforced levels of quality, reliability and safety. In order to achieve this vision, the current bus and taxi operators will need to be unified into a viable and operational entity structure which will provide the required services to the public. The main research problem has therefore been identified as follows: How can the bus and taxi operators in Nelson Mandela Bay be integrated into a single entity, or small number of entities, in order to provide a viable, efficient and sustainable public transport service? This research paper sought to address this problem by conducting a case study of the Nelson Mandela Bay project, which took place over the course of a one year period. The author served as the project manager on the team that was responsible for developing the integration model. Additional research included a study visit to the cities of Bogota and Pereira in Colombia, which have implemented similar transport models, as well as a secondary study focusing on generic organisational integration strategies in existing literature. This paper is fundamentally a qualitative study. In this light, the research data was analysed according to the quasi-judicial method, which was deemed most suitable to the case study format adopted. The findings of the analysis were evaluated, and based on the resultant conclusions, a final integration model was recommended. The fact that this study is based on an actual project that has real world implications and consequences makes the result very relevant, and as such it will serve as a valuable addition to the body of knowledge which can be of assistance to other cities or project teams facing similar challenges in South Africa or even internationally.
- Full Text:
- Date Issued: 2008
Development of methodologies for deploying and implementing local & medium area broadband PLC networks in office and residential electric grids
- Authors: Tinarwo, Loyd
- Date: 2008
- Subjects: Broadband communication systems , Power transmission , Telecommunication lines
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11375 , http://hdl.handle.net/10353/83 , Broadband communication systems , Power transmission , Telecommunication lines
- Description: The use of electrical networks for telecommunications has a long history. It has been known since the beginning of the twentieth century [Ahola03]. The idea of using electrical networks for broadband communications arose in the 1990s [Hrasnica et al 04]. Recent and growing research interest has indicated that PowerLine Communications (PLC) is the threshold for achieving broadband delivery particularly in very dispersed and low teledensity areas. Currently, there are numerous PLC trials and commercial deployments underway inside and outside South Africa. Nevertheless, these PLC deployments are very isolated, done without clear methodology and performance remains bound to the physical layout of the electrical network. Because of that high bandwidth broadband PLC systems are prone to poor performance and this in turn limits the acceptance and deployment of this emerging alternative broadband technology. Though, PLC technical challenges are being addressed, there has been little analysis and research work that is focused on the “Development of Methodologies for Deploying and Implementing Local & Medium Area Broadband Power Line in Residential and Office Electric Grids” that would lead to broadband PLC being adopted and be of greater use to non-broadband communities of South Africa. PLC is a term describing several different systems using electrical grid distribution wires for simultaneous distribution of data by superimposing an analog signal [Hrasnica et al 04]. The research proposed and presented broadband PLC methodologies for typical medium voltage and local voltage PLC networks. These methodologieswere implemented and experimented with in configurations which closely mirrored residential and office settings through laboratory and multibuilding experiments using commercial 2nd Generation Mitsubishi Electric PLC technology. Research results presented not only serve to provide insight into broadband PLC but also how it handled broadband applications (communications), competed and compared with other technologies such as Ethernet LAN. In combination with networking communication theories, the research explored and analyzed the extent of PLC in providing broadband communication to residential and office electric grids at the University Fort Hare, Computer Science Department.
- Full Text:
- Date Issued: 2008
- Authors: Tinarwo, Loyd
- Date: 2008
- Subjects: Broadband communication systems , Power transmission , Telecommunication lines
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11375 , http://hdl.handle.net/10353/83 , Broadband communication systems , Power transmission , Telecommunication lines
- Description: The use of electrical networks for telecommunications has a long history. It has been known since the beginning of the twentieth century [Ahola03]. The idea of using electrical networks for broadband communications arose in the 1990s [Hrasnica et al 04]. Recent and growing research interest has indicated that PowerLine Communications (PLC) is the threshold for achieving broadband delivery particularly in very dispersed and low teledensity areas. Currently, there are numerous PLC trials and commercial deployments underway inside and outside South Africa. Nevertheless, these PLC deployments are very isolated, done without clear methodology and performance remains bound to the physical layout of the electrical network. Because of that high bandwidth broadband PLC systems are prone to poor performance and this in turn limits the acceptance and deployment of this emerging alternative broadband technology. Though, PLC technical challenges are being addressed, there has been little analysis and research work that is focused on the “Development of Methodologies for Deploying and Implementing Local & Medium Area Broadband Power Line in Residential and Office Electric Grids” that would lead to broadband PLC being adopted and be of greater use to non-broadband communities of South Africa. PLC is a term describing several different systems using electrical grid distribution wires for simultaneous distribution of data by superimposing an analog signal [Hrasnica et al 04]. The research proposed and presented broadband PLC methodologies for typical medium voltage and local voltage PLC networks. These methodologieswere implemented and experimented with in configurations which closely mirrored residential and office settings through laboratory and multibuilding experiments using commercial 2nd Generation Mitsubishi Electric PLC technology. Research results presented not only serve to provide insight into broadband PLC but also how it handled broadband applications (communications), competed and compared with other technologies such as Ethernet LAN. In combination with networking communication theories, the research explored and analyzed the extent of PLC in providing broadband communication to residential and office electric grids at the University Fort Hare, Computer Science Department.
- Full Text:
- Date Issued: 2008
Development of platinum metal specific separating agents
- Authors: Jonck, Heine
- Date: 2008
- Subjects: Platinum , Platinum -- Separation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10401 , http://hdl.handle.net/10948/712 , Platinum , Platinum -- Separation
- Description: In this dissertation, the aim was to develop a platinum specific resin to be utilized for the early removal of platinum from the industrial feed solution. Efforts were therefore directed towards the syntheses of silica based resins, with active centra, designed for platinum. The large chlorometallate ions present in the feed stream, were characterized in terms of physical parameters relevant to phase distribution, namely distortability (RD), charge density, softness (σ) etc. Matching cations for each of the types were investigated. In order to attempt the design of platinum specific resins, different structural amines were used to aminate the silicone precursor and to subsequently fix these onto the silica framework. Two different solvents namely alcohol and dmf were used in this process, resulting in two sets of resins, with different properties. The design was based on previous experience with these ions, with reference to their behaviour towards different types of cations. The platinum species, PtCl6 2- and PtCl4 2-, as well as the most important contaminants in the feed stream, were typified, bearing in mind size, charge, charge density and distortability. Different types of cationic centra, having differences in charge density, stereochemical crowding and extent of hydrophobicity, were synthesized and tested-both as solvent extractants (where possible) and silica based resins. The results indicated that, partly screened secondary ammonium cationic resin species, which could be regarded as “intermediate”, proved to be satisfactory both in their high percentage extraction for PtCl4 2- and rejection of contaminants like chlororhodates, chloroiridates(III) and FeCl4 -. It was however necessary, to work at a redox potential, where iridium(IV) in the form of IrCl6 2-, was absent. Various 2-aminoalkane resins were prepared, with variation in the length of alkane group and synthesised by the two different solvents. The latter resulted in two sets of resins with not only differing compactness, but also having significantly different properties with reference to platinum specificity, HCl effect and stripping potential. The 2-aminobutane and 2-aminoheptane resins in particular, proved to be very satisfactory platinum specific resins, both with respect to selectivity, platinum capacity and stripping potential. The various physical parameters could be applied to identify the chemical behaviour of anions and assist in the development of anion specificity for the relevant species.
- Full Text:
- Date Issued: 2008
- Authors: Jonck, Heine
- Date: 2008
- Subjects: Platinum , Platinum -- Separation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10401 , http://hdl.handle.net/10948/712 , Platinum , Platinum -- Separation
- Description: In this dissertation, the aim was to develop a platinum specific resin to be utilized for the early removal of platinum from the industrial feed solution. Efforts were therefore directed towards the syntheses of silica based resins, with active centra, designed for platinum. The large chlorometallate ions present in the feed stream, were characterized in terms of physical parameters relevant to phase distribution, namely distortability (RD), charge density, softness (σ) etc. Matching cations for each of the types were investigated. In order to attempt the design of platinum specific resins, different structural amines were used to aminate the silicone precursor and to subsequently fix these onto the silica framework. Two different solvents namely alcohol and dmf were used in this process, resulting in two sets of resins, with different properties. The design was based on previous experience with these ions, with reference to their behaviour towards different types of cations. The platinum species, PtCl6 2- and PtCl4 2-, as well as the most important contaminants in the feed stream, were typified, bearing in mind size, charge, charge density and distortability. Different types of cationic centra, having differences in charge density, stereochemical crowding and extent of hydrophobicity, were synthesized and tested-both as solvent extractants (where possible) and silica based resins. The results indicated that, partly screened secondary ammonium cationic resin species, which could be regarded as “intermediate”, proved to be satisfactory both in their high percentage extraction for PtCl4 2- and rejection of contaminants like chlororhodates, chloroiridates(III) and FeCl4 -. It was however necessary, to work at a redox potential, where iridium(IV) in the form of IrCl6 2-, was absent. Various 2-aminoalkane resins were prepared, with variation in the length of alkane group and synthesised by the two different solvents. The latter resulted in two sets of resins with not only differing compactness, but also having significantly different properties with reference to platinum specificity, HCl effect and stripping potential. The 2-aminobutane and 2-aminoheptane resins in particular, proved to be very satisfactory platinum specific resins, both with respect to selectivity, platinum capacity and stripping potential. The various physical parameters could be applied to identify the chemical behaviour of anions and assist in the development of anion specificity for the relevant species.
- Full Text:
- Date Issued: 2008
Die liturgiese gebruik van die orrel in 'n post-mordene era: persepsies van kerkmusici en leraars van die Nederduitse Gereformeerde gemeentes in Port Elizabeth
- Authors: Heunis, Sulani
- Date: 2008
- Subjects: Organ music -- South Africa -- Port Elizabeth , Chorale preludes
- Language: Afrikaans
- Type: Thesis , Masters , MMus
- Identifier: vital:8511 , http://hdl.handle.net/10948/787 , Organ music -- South Africa -- Port Elizabeth , Chorale preludes
- Description: In this study the liturgical usage of the organ is investigated within a post-modern society. It focuses specifically on the church services of the Dutch Reformed Congregations of Port Elizabeth with regards to the functionality of the organ during morning and evening services. The objectives of the study are to demonstrate the current situation of musical worship in the Dutch Reformed Congregations of Port Elizabeth. Furthermore it serves as a way to indicate any deficiency in the field, which would need to be addressed. In order to achieve these objectives, both a qualitative and quantitative study is undertaken. The qualitative study investigates existing literature regarding the church service and its music. The quantitative study comprises an analysis of self-administered questionnaires that was handed over for completion by the Dutch Reformed Congregations of Port Elizabeth. The results obtained were electronically processed to percentages and graphic illustrations. In this mini-treatise it is argued that the usage of other music instruments (in the form of music worship groups) during church services could possibly lead to a change in the liturgical function of the organ. It was found that the usage of the organ in the Dutch Reformed Congregations of Port Elizabeth was mainly retained during morning services. During evening services however, the usage of other music instruments was in the majority, which resulted in a decrease of organ usage. It was further discovered that a large group of organists are not involved with music worship groups. Training of organists in a contemporary style of music worship will therefore serve as a significant purpose to fulfil this deficiency.
- Full Text:
- Date Issued: 2008
- Authors: Heunis, Sulani
- Date: 2008
- Subjects: Organ music -- South Africa -- Port Elizabeth , Chorale preludes
- Language: Afrikaans
- Type: Thesis , Masters , MMus
- Identifier: vital:8511 , http://hdl.handle.net/10948/787 , Organ music -- South Africa -- Port Elizabeth , Chorale preludes
- Description: In this study the liturgical usage of the organ is investigated within a post-modern society. It focuses specifically on the church services of the Dutch Reformed Congregations of Port Elizabeth with regards to the functionality of the organ during morning and evening services. The objectives of the study are to demonstrate the current situation of musical worship in the Dutch Reformed Congregations of Port Elizabeth. Furthermore it serves as a way to indicate any deficiency in the field, which would need to be addressed. In order to achieve these objectives, both a qualitative and quantitative study is undertaken. The qualitative study investigates existing literature regarding the church service and its music. The quantitative study comprises an analysis of self-administered questionnaires that was handed over for completion by the Dutch Reformed Congregations of Port Elizabeth. The results obtained were electronically processed to percentages and graphic illustrations. In this mini-treatise it is argued that the usage of other music instruments (in the form of music worship groups) during church services could possibly lead to a change in the liturgical function of the organ. It was found that the usage of the organ in the Dutch Reformed Congregations of Port Elizabeth was mainly retained during morning services. During evening services however, the usage of other music instruments was in the majority, which resulted in a decrease of organ usage. It was further discovered that a large group of organists are not involved with music worship groups. Training of organists in a contemporary style of music worship will therefore serve as a significant purpose to fulfil this deficiency.
- Full Text:
- Date Issued: 2008
Diet and feeding effects of introduced giraffe in the Eastern Cape
- Authors: Jacobs, Evert Philippus
- Date: 2008
- Subjects: Giraffe -- Food -- South Africa -- Eastern Cape , Giraffe -- Ecology -- South Africa -- Eastern Cape , Animal-plant relationships -- South Africa -- Eastern Cape , Introduced mammals -- Ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10703 , http://hdl.handle.net/10948/964 , Giraffe -- Food -- South Africa -- Eastern Cape , Giraffe -- Ecology -- South Africa -- Eastern Cape , Animal-plant relationships -- South Africa -- Eastern Cape , Introduced mammals -- Ecology -- South Africa -- Eastern Cape
- Description: This study presents the results of a study on introduced giraffe diet and feeding effects within the Eastern Cape Province of South Africa. Five sites were selected over a moisture gradient from the mesic east to the arid west of the Eastern Cape to describe giraffe diet and provide baseline data for feeding effect experiments. At each site faecal samples were collected seasonally and diet composition determined by microhistological analysis. Plant species availability was measured using the point intersect method in order to compare plant availability to plant consumption to determine diet preferences. Giraffe diet across the sites showed a unimodal response to rainfall by utilising fewer species in drier areas where plant availability is low and increasing the number of species consumed as the rainfall increases. In higher rainfall areas, giraffe reduced the number of plant species fed upon because of the high availability of important species that reduces the need for a varied diet. Across all sites, plant availability was dominated by woody plant species (more than 90 percent at each site). A total of 57 plants species were recorded as being eaten across the five sites. Several PDI (Principle Diet Items) plant species (Acacia karroo, Schotia afra, Pappea capensis and Euclea undulata) were eaten across sites. Over all the sites, significantly preferred species were Asparagus striatus, Schotia latifolia, Asparagus suaveolens, Commelina benghalensis, Viscum rotundifolium, and Acacia cyclops. Acacia karroo, Schotia afra, Pappea capensis, Rhus crenata, A. tetracantha, and Grewia robusta were utilised in proportion to their availability. Euclea undulata, Rhus longispina and Putterlickia pyracantha were avoided. Feeding effects were tested by erecting exclosures around trees, covering one half of each tree. Ten trees were selected for these manipulative experiments which ran from September 2003 to February 2005. The number of branches, number of leaves, branch orders, branch diameter, branch length, leaf length and leaf width were measured for ten samples per side (enclosed vs. exposed) and analysed using a Wilcoxon matched pairs test and tested for effect size using Cohen’s d. Although no significant differences were detected between the sides measured, the effect size indicated differences in all measurements between sides ranging from low to moderate. Leaf length was greater on the outside of exclosures and showed a moderate difference between the sides in terms of the d-value with the p-value (0.059) tending towards significance. Although leaf width was higher on the inside of exclosures, it only showed a moderate difference for d with no statistical significance. Leaf area was higher on the inside of exclosures and tended to significance (p = 0.059) and similarly the d value indicated moderate differences between the sides in terms of effect size. Similarly branch length was higher on the inside of exclosures although not significantly, the p-value (0.07) approached significance. The effect size for branch length also showed a moderate difference between the sides. The number of branches and the number of leaves showed no statistical differences between the sides although the p-value (0.059) for the number of branches, as well as number of leaves (p = 0.07) approached significance. For both these variables, effect size showed a moderate difference. Giraffe showed diversity in their diet selection across sites but mainly fed upon available species. Some preferred species were however less available and this preference could possibly result in increased pressure on the selected plant species Exclosure experiments showed no significant differences in leaf and shoot characteristics although all measurements showed differences in terms of effect size meriting further investigation. It is concluded that giraffe impact on sites may be reduced if populations are properly managed however, high densities of giraffe could lead to similar vegetation impacts as observed in other areas where giraffe have been introduced and potentially change vegetation structure and plant community composition.
- Full Text:
- Date Issued: 2008
- Authors: Jacobs, Evert Philippus
- Date: 2008
- Subjects: Giraffe -- Food -- South Africa -- Eastern Cape , Giraffe -- Ecology -- South Africa -- Eastern Cape , Animal-plant relationships -- South Africa -- Eastern Cape , Introduced mammals -- Ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10703 , http://hdl.handle.net/10948/964 , Giraffe -- Food -- South Africa -- Eastern Cape , Giraffe -- Ecology -- South Africa -- Eastern Cape , Animal-plant relationships -- South Africa -- Eastern Cape , Introduced mammals -- Ecology -- South Africa -- Eastern Cape
- Description: This study presents the results of a study on introduced giraffe diet and feeding effects within the Eastern Cape Province of South Africa. Five sites were selected over a moisture gradient from the mesic east to the arid west of the Eastern Cape to describe giraffe diet and provide baseline data for feeding effect experiments. At each site faecal samples were collected seasonally and diet composition determined by microhistological analysis. Plant species availability was measured using the point intersect method in order to compare plant availability to plant consumption to determine diet preferences. Giraffe diet across the sites showed a unimodal response to rainfall by utilising fewer species in drier areas where plant availability is low and increasing the number of species consumed as the rainfall increases. In higher rainfall areas, giraffe reduced the number of plant species fed upon because of the high availability of important species that reduces the need for a varied diet. Across all sites, plant availability was dominated by woody plant species (more than 90 percent at each site). A total of 57 plants species were recorded as being eaten across the five sites. Several PDI (Principle Diet Items) plant species (Acacia karroo, Schotia afra, Pappea capensis and Euclea undulata) were eaten across sites. Over all the sites, significantly preferred species were Asparagus striatus, Schotia latifolia, Asparagus suaveolens, Commelina benghalensis, Viscum rotundifolium, and Acacia cyclops. Acacia karroo, Schotia afra, Pappea capensis, Rhus crenata, A. tetracantha, and Grewia robusta were utilised in proportion to their availability. Euclea undulata, Rhus longispina and Putterlickia pyracantha were avoided. Feeding effects were tested by erecting exclosures around trees, covering one half of each tree. Ten trees were selected for these manipulative experiments which ran from September 2003 to February 2005. The number of branches, number of leaves, branch orders, branch diameter, branch length, leaf length and leaf width were measured for ten samples per side (enclosed vs. exposed) and analysed using a Wilcoxon matched pairs test and tested for effect size using Cohen’s d. Although no significant differences were detected between the sides measured, the effect size indicated differences in all measurements between sides ranging from low to moderate. Leaf length was greater on the outside of exclosures and showed a moderate difference between the sides in terms of the d-value with the p-value (0.059) tending towards significance. Although leaf width was higher on the inside of exclosures, it only showed a moderate difference for d with no statistical significance. Leaf area was higher on the inside of exclosures and tended to significance (p = 0.059) and similarly the d value indicated moderate differences between the sides in terms of effect size. Similarly branch length was higher on the inside of exclosures although not significantly, the p-value (0.07) approached significance. The effect size for branch length also showed a moderate difference between the sides. The number of branches and the number of leaves showed no statistical differences between the sides although the p-value (0.059) for the number of branches, as well as number of leaves (p = 0.07) approached significance. For both these variables, effect size showed a moderate difference. Giraffe showed diversity in their diet selection across sites but mainly fed upon available species. Some preferred species were however less available and this preference could possibly result in increased pressure on the selected plant species Exclosure experiments showed no significant differences in leaf and shoot characteristics although all measurements showed differences in terms of effect size meriting further investigation. It is concluded that giraffe impact on sites may be reduced if populations are properly managed however, high densities of giraffe could lead to similar vegetation impacts as observed in other areas where giraffe have been introduced and potentially change vegetation structure and plant community composition.
- Full Text:
- Date Issued: 2008
Drought responses of C3 and C4 (NADP-ME) Panicoid grasses
- Authors: Frole, Kristen Marie
- Date: 2008
- Subjects: Botany -- Research , Grasses -- Physiology -- South Africa , Grasses -- Effect of drought on , Grasses -- Drought tolerance , Plant-water relationships
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4193 , http://hdl.handle.net/10962/d1003762 , Botany -- Research , Grasses -- Physiology -- South Africa , Grasses -- Effect of drought on , Grasses -- Drought tolerance , Plant-water relationships
- Description: The success of C₄ plants lies in their ability to concentrate CO₂ at the site of Rubisco thereby conferring greater efficiencies of light, water and nitrogen. Such characteristics should advantage C₄ plants in arid, hot environments. However, not all C₄ subtypes are drought tolerant. The relative abundance of NADP-ME species declines with increasing aridity. Furthermore, selected species have been demonstrated as being susceptible to severe drought showing metabolic limitations of photosynthesis. However there is a lack of phylogenetic control with many of these studies. The aims of this study were to determine whether the NADP-ME subtype was inherently susceptible to drought by comparing six closely related C₃ and C₄ (NADP-ME) Panicoid grasses. Gas exchange measurements were made during a natural rainless period and a controlled drought / rewatering event. Prior to water stress, the C₄ species had higher assimilation rates (A), and water use efficiencies (WUE[subscript leaf]) than the C₃ species, while transpiration rates (E) and stomatal conductances (g[subscript s]) were similar. At low soil water content, the C₃ species reduced gs by a greater extent than the C₄ species, which maintained higher E during the driest periods. The C₄ species showed proportionally greater reductions in A than the C₃ species and hence lost their WUE[subscript leaf] and photosynthetic advantage. CO₂ response curves showed that metabolic limitation was responsible for a greater decrease in A in the C₄ type than the C₃ type during progressive drought. Upon re-watering, photosynthetic recovery was quicker in the C species than the C₄ species. Results from whole plant measurements showed that the C₄ type had a significant whole plant water use efficiency advantage over the C₃ type under well-watered conditions that was lost during severe drought due to a greater loss of leaf area through leaf mortality rather than reductions in plant level transpiration rates. The C₃ type had xylem characteristics that enhanced water-conducting efficiency, but made them vulnerable to drought. This is in contrast to the safer xylem qualities of the C₄ type, which permitted the endurance of more negative leaf water potentials than the C₃ type during low soil water content. Thus, the vulnerability of photosynthesis to severe drought in NADP-ME species potentially explains why NADP-ME species abundance around the world decreases with decreasing rainfall.
- Full Text:
- Date Issued: 2008
- Authors: Frole, Kristen Marie
- Date: 2008
- Subjects: Botany -- Research , Grasses -- Physiology -- South Africa , Grasses -- Effect of drought on , Grasses -- Drought tolerance , Plant-water relationships
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4193 , http://hdl.handle.net/10962/d1003762 , Botany -- Research , Grasses -- Physiology -- South Africa , Grasses -- Effect of drought on , Grasses -- Drought tolerance , Plant-water relationships
- Description: The success of C₄ plants lies in their ability to concentrate CO₂ at the site of Rubisco thereby conferring greater efficiencies of light, water and nitrogen. Such characteristics should advantage C₄ plants in arid, hot environments. However, not all C₄ subtypes are drought tolerant. The relative abundance of NADP-ME species declines with increasing aridity. Furthermore, selected species have been demonstrated as being susceptible to severe drought showing metabolic limitations of photosynthesis. However there is a lack of phylogenetic control with many of these studies. The aims of this study were to determine whether the NADP-ME subtype was inherently susceptible to drought by comparing six closely related C₃ and C₄ (NADP-ME) Panicoid grasses. Gas exchange measurements were made during a natural rainless period and a controlled drought / rewatering event. Prior to water stress, the C₄ species had higher assimilation rates (A), and water use efficiencies (WUE[subscript leaf]) than the C₃ species, while transpiration rates (E) and stomatal conductances (g[subscript s]) were similar. At low soil water content, the C₃ species reduced gs by a greater extent than the C₄ species, which maintained higher E during the driest periods. The C₄ species showed proportionally greater reductions in A than the C₃ species and hence lost their WUE[subscript leaf] and photosynthetic advantage. CO₂ response curves showed that metabolic limitation was responsible for a greater decrease in A in the C₄ type than the C₃ type during progressive drought. Upon re-watering, photosynthetic recovery was quicker in the C species than the C₄ species. Results from whole plant measurements showed that the C₄ type had a significant whole plant water use efficiency advantage over the C₃ type under well-watered conditions that was lost during severe drought due to a greater loss of leaf area through leaf mortality rather than reductions in plant level transpiration rates. The C₃ type had xylem characteristics that enhanced water-conducting efficiency, but made them vulnerable to drought. This is in contrast to the safer xylem qualities of the C₄ type, which permitted the endurance of more negative leaf water potentials than the C₃ type during low soil water content. Thus, the vulnerability of photosynthesis to severe drought in NADP-ME species potentially explains why NADP-ME species abundance around the world decreases with decreasing rainfall.
- Full Text:
- Date Issued: 2008
Dumping, antidumping and the future prospects for fair international trade
- Authors: Zvidza, Tinevimbo
- Date: 2008
- Subjects: Dumping -- International trade -- International trade -- Fair trad , Foreign trade regulation -- International cooperation
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11114 , http://hdl.handle.net/10353/100 , Dumping -- International trade -- International trade -- Fair trad , Foreign trade regulation -- International cooperation
- Description: More than a century has passed since Canada adopted the first antidumping law in 1904. Similar legislation in most of the major trading nations followed the Canadian legislation prior to and after the World War II. Antidumping provisions were later integrated into the General Agreement on Tariffs and Trade (GATT) after the said war. Today, nearly all developed and developing countries have this type of legislation in place within their municipal legal framework. The subject of antidumping has received growing attention in international trade policy and has become a source of tension between trading nations. This is evident in the substantial increase of antidumping actions since the establishment of the WTO. Antidumping policy has emerged as a significant trade barrier because of its misuse by both developed and developing countries. The primary instruments governing antidumping actions are GATT Article VI and the Antidumping Agreement (ADA). The ADA contains both the substantive and procedural rules governing the interpretation and application of the instrument. Its purpose is to ensure that the instrument is used only as a contingency measure judged upon merit and not as a disguised protectionist device. Given the growing number of countries participating more actively in the world trading system and the notorious misuse of antidumping provisions, there is a vital need to critically analyse the key provisions of the said instruments. This study is an attempt at that academic enterprise. It concludes by giving proposals for future reform of both real and potential future reform of the current WTO antidumping regime. Dumping, antidumping, antidumping regulation, antidumping duties, like products, dumping margin, zeroing, facts available, protectionism, ADA.
- Full Text:
- Date Issued: 2008
- Authors: Zvidza, Tinevimbo
- Date: 2008
- Subjects: Dumping -- International trade -- International trade -- Fair trad , Foreign trade regulation -- International cooperation
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11114 , http://hdl.handle.net/10353/100 , Dumping -- International trade -- International trade -- Fair trad , Foreign trade regulation -- International cooperation
- Description: More than a century has passed since Canada adopted the first antidumping law in 1904. Similar legislation in most of the major trading nations followed the Canadian legislation prior to and after the World War II. Antidumping provisions were later integrated into the General Agreement on Tariffs and Trade (GATT) after the said war. Today, nearly all developed and developing countries have this type of legislation in place within their municipal legal framework. The subject of antidumping has received growing attention in international trade policy and has become a source of tension between trading nations. This is evident in the substantial increase of antidumping actions since the establishment of the WTO. Antidumping policy has emerged as a significant trade barrier because of its misuse by both developed and developing countries. The primary instruments governing antidumping actions are GATT Article VI and the Antidumping Agreement (ADA). The ADA contains both the substantive and procedural rules governing the interpretation and application of the instrument. Its purpose is to ensure that the instrument is used only as a contingency measure judged upon merit and not as a disguised protectionist device. Given the growing number of countries participating more actively in the world trading system and the notorious misuse of antidumping provisions, there is a vital need to critically analyse the key provisions of the said instruments. This study is an attempt at that academic enterprise. It concludes by giving proposals for future reform of both real and potential future reform of the current WTO antidumping regime. Dumping, antidumping, antidumping regulation, antidumping duties, like products, dumping margin, zeroing, facts available, protectionism, ADA.
- Full Text:
- Date Issued: 2008
Ecological role of free-living bacteria in the microbial food web of the temporarily open/closed East Kleinemonde Estuary, South Africa
- Authors: Allan, Elizabeth Louise
- Date: 2008
- Subjects: Bacterial growth -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape , Estuaries -- South Africa -- Eastern Cape , Microbial ecology -- South Africa -- Eastern Cape , Nutrient cycles -- South Africa -- Eastern Cape , Food chains (Ecology)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5666 , http://hdl.handle.net/10962/d1005351 , Bacterial growth -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape , Estuaries -- South Africa -- Eastern Cape , Microbial ecology -- South Africa -- Eastern Cape , Nutrient cycles -- South Africa -- Eastern Cape , Food chains (Ecology)
- Description: The main aim of this study was to assess the “top-down” and “bottom-up” control of bacterial production in the small temporarily open/closed East Kleinemonde Estuary, situated on the south-eastern coastline of southern Africa. Spatial and temporal patterns in bacterial abundance, biomass and production and the importance of abiotic and biotic factors were investigated over the period May 2006 to April 2007. The trophic interactions between bacteria, phytoplankton, nanoflagellates (< 20 μm), microzooplankton (< 200 μm) and mesozooplankton (< 2 000 μm) were investigated during winter and summer. Bacterial abundance, biomass and production ranged between 1.00 × 10⁹ and 4.93 × 10⁹ cells 1⁻¹, 32.4 and 109 μg C 1⁻¹ and 0.01 and 1.99 μg C 1⁻¹ h⁻¹, respectively. With a few exceptions there were no spatial patterns in the values. Bacterial abundance, biomass and production, however, demonstrated a distinct temporal pattern with the lowest values consistently recorded during the winter months. Nanoflagellate and bacterial abundances were significantly correlated to one another (lower reaches: r = 0.818, p < 0.001; middle reaches: r = 0.628, p < 0.001; upper reaches: r = 0.484, p < 0.05) suggesting a strong predator-prey relationship. The frequency of visibly infected bacterial cells and the mean number of virus particles within each bacterial cell during this study demonstrated no temporal or spatial patterns and ranged from 0.5 to 6.1 % and 12.0 to 37.5 virus particles per bacterium, respectively. Viral infection and lysis was thus a constant source of bacterial mortality throughout the year. The estimated percentage of bacterial production removed by viral lysis ranged between 7.8 and 88.9% of the total which suggests that viral lysis represented a very important source of bacterial mortality during this study. The biological interactions between the selected components of the plankton community demonstrated that among the heterotrophic components of the plankton, the nanoflagellates were identified as the most important consumers of bacteria and small phytoplankton cells (< 20 μm). In the presence of microzooplankton the impact of the nanoflagellates on both the bacteria and phytoplankton was reduced, indicating that larger heterotrophs were preying upon the nanoflagellates. Mesozooplankton, however, appeared to exert the greatest impact on nanoflagellates. In the cascading experiments, the data suggest that mesozooplankton consume nanoflagellates, which resulted in a decrease in the predation impact of these organisms on the bacteria. This result is consistent with predator-prey cascades. The presence of the larger heterotrophs therefore, mediates the interactions between the primary bacterivores, the nanoflagellates, and the bacteria within the temporarily open/closed East Kleinemonde Estuary.
- Full Text:
- Date Issued: 2008
- Authors: Allan, Elizabeth Louise
- Date: 2008
- Subjects: Bacterial growth -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape , Estuaries -- South Africa -- Eastern Cape , Microbial ecology -- South Africa -- Eastern Cape , Nutrient cycles -- South Africa -- Eastern Cape , Food chains (Ecology)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5666 , http://hdl.handle.net/10962/d1005351 , Bacterial growth -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape , Estuaries -- South Africa -- Eastern Cape , Microbial ecology -- South Africa -- Eastern Cape , Nutrient cycles -- South Africa -- Eastern Cape , Food chains (Ecology)
- Description: The main aim of this study was to assess the “top-down” and “bottom-up” control of bacterial production in the small temporarily open/closed East Kleinemonde Estuary, situated on the south-eastern coastline of southern Africa. Spatial and temporal patterns in bacterial abundance, biomass and production and the importance of abiotic and biotic factors were investigated over the period May 2006 to April 2007. The trophic interactions between bacteria, phytoplankton, nanoflagellates (< 20 μm), microzooplankton (< 200 μm) and mesozooplankton (< 2 000 μm) were investigated during winter and summer. Bacterial abundance, biomass and production ranged between 1.00 × 10⁹ and 4.93 × 10⁹ cells 1⁻¹, 32.4 and 109 μg C 1⁻¹ and 0.01 and 1.99 μg C 1⁻¹ h⁻¹, respectively. With a few exceptions there were no spatial patterns in the values. Bacterial abundance, biomass and production, however, demonstrated a distinct temporal pattern with the lowest values consistently recorded during the winter months. Nanoflagellate and bacterial abundances were significantly correlated to one another (lower reaches: r = 0.818, p < 0.001; middle reaches: r = 0.628, p < 0.001; upper reaches: r = 0.484, p < 0.05) suggesting a strong predator-prey relationship. The frequency of visibly infected bacterial cells and the mean number of virus particles within each bacterial cell during this study demonstrated no temporal or spatial patterns and ranged from 0.5 to 6.1 % and 12.0 to 37.5 virus particles per bacterium, respectively. Viral infection and lysis was thus a constant source of bacterial mortality throughout the year. The estimated percentage of bacterial production removed by viral lysis ranged between 7.8 and 88.9% of the total which suggests that viral lysis represented a very important source of bacterial mortality during this study. The biological interactions between the selected components of the plankton community demonstrated that among the heterotrophic components of the plankton, the nanoflagellates were identified as the most important consumers of bacteria and small phytoplankton cells (< 20 μm). In the presence of microzooplankton the impact of the nanoflagellates on both the bacteria and phytoplankton was reduced, indicating that larger heterotrophs were preying upon the nanoflagellates. Mesozooplankton, however, appeared to exert the greatest impact on nanoflagellates. In the cascading experiments, the data suggest that mesozooplankton consume nanoflagellates, which resulted in a decrease in the predation impact of these organisms on the bacteria. This result is consistent with predator-prey cascades. The presence of the larger heterotrophs therefore, mediates the interactions between the primary bacterivores, the nanoflagellates, and the bacteria within the temporarily open/closed East Kleinemonde Estuary.
- Full Text:
- Date Issued: 2008
Economic valuation of communal rangelands in the Eastern Cape Province of South Africa
- Authors: Gombakomba, Gift
- Date: 2008
- Subjects: Rangelands -- South Africa -- Eastern Cape -- Evaluation , Rural development -- South Africa -- Eastern Cape -- Evaluation , Commons -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11166 , http://hdl.handle.net/10353/351 , Rangelands -- South Africa -- Eastern Cape -- Evaluation , Rural development -- South Africa -- Eastern Cape -- Evaluation , Commons -- South Africa -- Eastern Cape
- Description: The exploitation and conversion of rangeland ecosystems is often explained by economists as being the result of an undervaluation of the goods and services provided by the rangelands. Undervaluation of rangelands may contribute to their mismanagement or their transformation to monoculture, such as livestock or gathering. Similarly, this may lead to inappropriate policy recommendations and prescriptions. This study undertakes a valuation exercise in an effort to address causes of undervaluation. The objective of the study is to estimate the annual direct, indirect and non-use values per household of communal rangelands in the Eastern Cape Province, based on both primary and secondary data. The exercise incorporates the two major direct uses, both marketed and non-marketed, of rangelands - livestock and gathering. Contingent valuation method based on stated preferences by individual household was used to value the indirect and non-use values of the communal rangelands (e.g. erosion protection and burial sites). Data was collected using PRAs, structured questionnaires and interviews by trained enumerators. The study shows that half of the households owned livestock, which is the main economic use of the rangelands and gathering of natural resources also made an economic contribution. Every household was involved in collection of range resources such as fuel wood, wild fruits, thatch grass, building poles, hunting, fishing make a significant contribution to the direct use values: in the case of gathering it shows that there is “hidden harvest” of many of the natural resources from the rangelands. Indirect and non-use values are shown to be important in the communal areas but are difficult to quantify; the results of these are based on qualitative analysis. Keywords: communal rangelands, demand curve, direct use values, indirect use values, individuals’ preferences, non-use values, willingness-to-accept and willingness-to-pay.
- Full Text:
- Date Issued: 2008
- Authors: Gombakomba, Gift
- Date: 2008
- Subjects: Rangelands -- South Africa -- Eastern Cape -- Evaluation , Rural development -- South Africa -- Eastern Cape -- Evaluation , Commons -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11166 , http://hdl.handle.net/10353/351 , Rangelands -- South Africa -- Eastern Cape -- Evaluation , Rural development -- South Africa -- Eastern Cape -- Evaluation , Commons -- South Africa -- Eastern Cape
- Description: The exploitation and conversion of rangeland ecosystems is often explained by economists as being the result of an undervaluation of the goods and services provided by the rangelands. Undervaluation of rangelands may contribute to their mismanagement or their transformation to monoculture, such as livestock or gathering. Similarly, this may lead to inappropriate policy recommendations and prescriptions. This study undertakes a valuation exercise in an effort to address causes of undervaluation. The objective of the study is to estimate the annual direct, indirect and non-use values per household of communal rangelands in the Eastern Cape Province, based on both primary and secondary data. The exercise incorporates the two major direct uses, both marketed and non-marketed, of rangelands - livestock and gathering. Contingent valuation method based on stated preferences by individual household was used to value the indirect and non-use values of the communal rangelands (e.g. erosion protection and burial sites). Data was collected using PRAs, structured questionnaires and interviews by trained enumerators. The study shows that half of the households owned livestock, which is the main economic use of the rangelands and gathering of natural resources also made an economic contribution. Every household was involved in collection of range resources such as fuel wood, wild fruits, thatch grass, building poles, hunting, fishing make a significant contribution to the direct use values: in the case of gathering it shows that there is “hidden harvest” of many of the natural resources from the rangelands. Indirect and non-use values are shown to be important in the communal areas but are difficult to quantify; the results of these are based on qualitative analysis. Keywords: communal rangelands, demand curve, direct use values, indirect use values, individuals’ preferences, non-use values, willingness-to-accept and willingness-to-pay.
- Full Text:
- Date Issued: 2008
Education in the wetlands and wetlands in the education: a case of contextualizing primary/basic education in Tanzania
- Authors: Hogan, Alice Rosemary
- Date: 2008
- Subjects: Education -- Tanzania Environmental education -- Tanzania Education, Rural -- Tanzania Education -- Curricula -- Tanzania Community and school -- Tanzania
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1504 , http://hdl.handle.net/10962/d1003386
- Description: This dissertation describes an action research case study carried out at a sub-village school at Nyamakurukuru, Utete, Rufiji District, Tanzania. The study was a fully independent research activity funded and led by a female Irish environmental and community specialist who has fifteen years experience of working in rural Tanzania, five of which were in Rufiji District. The aim of the action research was to engage a community of villagers, teachers, students and district officers in a participatory process to adapt a module of a school curriculum to the local context, and teach it in order to describe one way in which contextualization, using local and indigenous knowledge and active discovery teaching-learning processes, can be done. The major research question, which I wished to answer for one specific case, was: Does integrating local environmental cultural knowledge into formal schooling contribute to curriculum relevance? If so, in what way? This document describes the background and context of the research, the motivation and the theoretical basis for the work, the methodology and methods, and the action research process itself. The results are interpreted and discussed in the light of current theoretical perspectives on education and environmental education. The main findings within the case are that: Contextualization improved relevance of education and thus its quality by: • breaking through traditional frames/barriers between teachers and students, students and elders and community and teachers, • allowing formal education to take place outside of the school, • necessitating a change in pedagogy1 to more learner-centered, discovery methods, • allowing indigenous knowledge to come into the classroom, • stimulating creativity and increased confidence, and • bringing local socio-political environmental issues into the classroom. This study provides a case example of how education processes, when engaging local cultural knowledge, can improve the relevance, and thus an aspect of the quality of teaching and learning in school-community contexts, while providing a conduit for integrating environmental education into the formal school curriculum. It provides insights into the key issue of relevance which currently faces educators of children in wetlands in Tanzania. Recommendations were made for the case studied and may be useful beyond the boundaries of the case: • Give more explicit government policy and strategic support for community involvement in educational content–epistemologies and pedagogies. • Weaken framing (hierarchical power positions) to encourage greater partnership between school, home and community to improve relevance. • Investigate the provision of education beyond schools. • Provide practical teacher and community training on use of learner-centered, discovery and active pedagogies. • Provide teacher and community education on biodiversity and the environment. • Provide relevant reference texts and research data on the ecology, biodiversity, vegetation, hydrology, agriculture, sociology, history and other relevant subjects. • Officially nurture a culture that learning should be enjoyable. • Allow the curriculum freedom, in these times of increasing risk for rural tropical wetland communities, to make the curriculum fit the local issues rather than vice versa. • Nurture critical analysis of the curriculum in local pedagogic discourse i.e., at the local contextualization level of the home, community and school.
- Full Text:
- Date Issued: 2008
- Authors: Hogan, Alice Rosemary
- Date: 2008
- Subjects: Education -- Tanzania Environmental education -- Tanzania Education, Rural -- Tanzania Education -- Curricula -- Tanzania Community and school -- Tanzania
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1504 , http://hdl.handle.net/10962/d1003386
- Description: This dissertation describes an action research case study carried out at a sub-village school at Nyamakurukuru, Utete, Rufiji District, Tanzania. The study was a fully independent research activity funded and led by a female Irish environmental and community specialist who has fifteen years experience of working in rural Tanzania, five of which were in Rufiji District. The aim of the action research was to engage a community of villagers, teachers, students and district officers in a participatory process to adapt a module of a school curriculum to the local context, and teach it in order to describe one way in which contextualization, using local and indigenous knowledge and active discovery teaching-learning processes, can be done. The major research question, which I wished to answer for one specific case, was: Does integrating local environmental cultural knowledge into formal schooling contribute to curriculum relevance? If so, in what way? This document describes the background and context of the research, the motivation and the theoretical basis for the work, the methodology and methods, and the action research process itself. The results are interpreted and discussed in the light of current theoretical perspectives on education and environmental education. The main findings within the case are that: Contextualization improved relevance of education and thus its quality by: • breaking through traditional frames/barriers between teachers and students, students and elders and community and teachers, • allowing formal education to take place outside of the school, • necessitating a change in pedagogy1 to more learner-centered, discovery methods, • allowing indigenous knowledge to come into the classroom, • stimulating creativity and increased confidence, and • bringing local socio-political environmental issues into the classroom. This study provides a case example of how education processes, when engaging local cultural knowledge, can improve the relevance, and thus an aspect of the quality of teaching and learning in school-community contexts, while providing a conduit for integrating environmental education into the formal school curriculum. It provides insights into the key issue of relevance which currently faces educators of children in wetlands in Tanzania. Recommendations were made for the case studied and may be useful beyond the boundaries of the case: • Give more explicit government policy and strategic support for community involvement in educational content–epistemologies and pedagogies. • Weaken framing (hierarchical power positions) to encourage greater partnership between school, home and community to improve relevance. • Investigate the provision of education beyond schools. • Provide practical teacher and community training on use of learner-centered, discovery and active pedagogies. • Provide teacher and community education on biodiversity and the environment. • Provide relevant reference texts and research data on the ecology, biodiversity, vegetation, hydrology, agriculture, sociology, history and other relevant subjects. • Officially nurture a culture that learning should be enjoyable. • Allow the curriculum freedom, in these times of increasing risk for rural tropical wetland communities, to make the curriculum fit the local issues rather than vice versa. • Nurture critical analysis of the curriculum in local pedagogic discourse i.e., at the local contextualization level of the home, community and school.
- Full Text:
- Date Issued: 2008
Educators perceived challenges in dealing with HIV and AIDS orphans and vulnerable children
- Authors: Goba, Linda
- Date: 2008
- Subjects: Children of AIDS patients -- Education -- South Africa , Orphans -- Education -- South Africa , Teachers -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9526 , http://hdl.handle.net/10948/963 , Children of AIDS patients -- Education -- South Africa , Orphans -- Education -- South Africa , Teachers -- South Africa -- Attitudes
- Description: The HIV and AIDS pandemic in South Africa has increased the number of orphans and vulnerable children in the school system. Given the prominent role that teachers can play in ensuring that these children receive a quality education so as to maximise their life opportunities, it is important for teachers to be empowered and equipped to enable them to deal with issues surrounding orphans and vulnerable children (OVC) at schools. This study focuses on how teachers are experiencing the impact of HIV and AIDS in schools as a result of having OVC in their classes. The Department of Education has developed training courses to help teachers cope with the impact of HIV and AIDS, but the effectiveness of these programmes has not yet been evaluated. This study aims to establish how teachers who have attended these programmes feel about the assistance rendered to them to deal with OVC related issues. In order to meet this aim, a qualitative enquiry was conducted among a sample of selected teachers from the Eastern Cape. The findings suggest that, while the training has helped to improve the knowledge and attitudes of the teachers, it has not equipped them with the necessary skills to overcome barriers to implement the training programmes at school level. The findings also suggest that there is a need for ongoing support from the Department of Education and the trainers it contracts to ensure that learning from the training is implemented in the schools. Based on the research findings, the study concludes with recommendations that will help teachers to better cope with OVC related issues at school.
- Full Text:
- Date Issued: 2008
- Authors: Goba, Linda
- Date: 2008
- Subjects: Children of AIDS patients -- Education -- South Africa , Orphans -- Education -- South Africa , Teachers -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9526 , http://hdl.handle.net/10948/963 , Children of AIDS patients -- Education -- South Africa , Orphans -- Education -- South Africa , Teachers -- South Africa -- Attitudes
- Description: The HIV and AIDS pandemic in South Africa has increased the number of orphans and vulnerable children in the school system. Given the prominent role that teachers can play in ensuring that these children receive a quality education so as to maximise their life opportunities, it is important for teachers to be empowered and equipped to enable them to deal with issues surrounding orphans and vulnerable children (OVC) at schools. This study focuses on how teachers are experiencing the impact of HIV and AIDS in schools as a result of having OVC in their classes. The Department of Education has developed training courses to help teachers cope with the impact of HIV and AIDS, but the effectiveness of these programmes has not yet been evaluated. This study aims to establish how teachers who have attended these programmes feel about the assistance rendered to them to deal with OVC related issues. In order to meet this aim, a qualitative enquiry was conducted among a sample of selected teachers from the Eastern Cape. The findings suggest that, while the training has helped to improve the knowledge and attitudes of the teachers, it has not equipped them with the necessary skills to overcome barriers to implement the training programmes at school level. The findings also suggest that there is a need for ongoing support from the Department of Education and the trainers it contracts to ensure that learning from the training is implemented in the schools. Based on the research findings, the study concludes with recommendations that will help teachers to better cope with OVC related issues at school.
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- Date Issued: 2008