Decent work and informal employment: the case of Bulawayo Metropolitan Province (Central Business District) Zimbabwe
- Authors: Bob, Shaka Keny
- Date: 2020
- Subjects: Labor -- Zimbabwe , Informal sector (Economics) -- Zimbabwe , Job creation -- Zimbabwe , Poor -- Zimbabwe -- Employment , Labor policy -- Zimbabwe , Football coaches -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/115241 , vital:34104
- Description: Zimbabwe, similar to other developing countries experiences a high level of informal employment. However, most informal jobs are situated in very poor working conditions and are characterised by decent work deficits. Despite the fact that various studies have shown the importance of the informal economy in that it provides livelihood earning opportunities for the majority of people in the Global South, it has remained a largely forgotten sector in policy making in most countries. It is, therefore, important that informal work be taken seriously and efforts must be made to improve working conditions for the urban working poor in the developing world. The purpose of this study is to investigate on the self-reported experiences of informal workers to understand their perspectives surrounding the concept of decent work in the Zimbabwean context. The case study is the Bulawayo metropolitan province, and this study targeted informal workers who trade within the central business district. The study also aimed to measure the decent work deficit scores between two economic sectors (food and clothing traders). This was done by testing the suitability of the Edward Webster Decent Work Deficit Index as a methodology of measuring decent work at a micro level. The analysis is based on a mixed methods study which was carried out through the use of a semi-structured survey. The study revealed that decent work for the sampled informal workers meant work related improvements, insurances and risk management, right of expression and business advancement skills which closely resembles the International Labour Organisation's conceptualisation of decent work. The study also highlighted that childcare assistance and disability insurance are concepts which remained excluded in the current conceptualisation of decent work. The thesis offers a new policy angle which shows that to promote decent work the concept of heterogeneity must be adopted because inequalities persist within the informal economy. The study also suggested that the Edward Webster Decent Work Deficit Index can be used as an appropriate methodology of monitoring the progress towards achieving decent work at the micro level i.e. industry or individual level. This is because since the formation of the decent work concept; the International Labour Organisation has only provided a methodology of how to measure the progress of decent work at the county level. The survey findings revealed that food vendors scored more poorly on the decent work deficit index compared to the clothing traders. The study also identified that food vendors and clothing traders are faced with different challenges which suggests that policy makers must take that into consideration when attempting to design policies or programmes which are aimed at assisting informal workers.
- Full Text:
- Date Issued: 2020
- Authors: Bob, Shaka Keny
- Date: 2020
- Subjects: Labor -- Zimbabwe , Informal sector (Economics) -- Zimbabwe , Job creation -- Zimbabwe , Poor -- Zimbabwe -- Employment , Labor policy -- Zimbabwe , Football coaches -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/115241 , vital:34104
- Description: Zimbabwe, similar to other developing countries experiences a high level of informal employment. However, most informal jobs are situated in very poor working conditions and are characterised by decent work deficits. Despite the fact that various studies have shown the importance of the informal economy in that it provides livelihood earning opportunities for the majority of people in the Global South, it has remained a largely forgotten sector in policy making in most countries. It is, therefore, important that informal work be taken seriously and efforts must be made to improve working conditions for the urban working poor in the developing world. The purpose of this study is to investigate on the self-reported experiences of informal workers to understand their perspectives surrounding the concept of decent work in the Zimbabwean context. The case study is the Bulawayo metropolitan province, and this study targeted informal workers who trade within the central business district. The study also aimed to measure the decent work deficit scores between two economic sectors (food and clothing traders). This was done by testing the suitability of the Edward Webster Decent Work Deficit Index as a methodology of measuring decent work at a micro level. The analysis is based on a mixed methods study which was carried out through the use of a semi-structured survey. The study revealed that decent work for the sampled informal workers meant work related improvements, insurances and risk management, right of expression and business advancement skills which closely resembles the International Labour Organisation's conceptualisation of decent work. The study also highlighted that childcare assistance and disability insurance are concepts which remained excluded in the current conceptualisation of decent work. The thesis offers a new policy angle which shows that to promote decent work the concept of heterogeneity must be adopted because inequalities persist within the informal economy. The study also suggested that the Edward Webster Decent Work Deficit Index can be used as an appropriate methodology of monitoring the progress towards achieving decent work at the micro level i.e. industry or individual level. This is because since the formation of the decent work concept; the International Labour Organisation has only provided a methodology of how to measure the progress of decent work at the county level. The survey findings revealed that food vendors scored more poorly on the decent work deficit index compared to the clothing traders. The study also identified that food vendors and clothing traders are faced with different challenges which suggests that policy makers must take that into consideration when attempting to design policies or programmes which are aimed at assisting informal workers.
- Full Text:
- Date Issued: 2020
Adoption and risk of mobile financial services: a case of some selected municipalities in Eastern Cape Province
- Authors: Aderibigbe, Ifeoluwa A.I
- Date: 2019
- Subjects: Mobile commerce Finance
- Language: English
- Type: Thesis , Masters , MCom (Economics)
- Identifier: http://hdl.handle.net/10353/13281 , vital:39630
- Description: The study investigated risk and adoption of mobile financial services among some users in selected municipalities within the Eastern Cape Province, using the theory of reason action, technology acceptance model and the theory of expected utility and risk aversion to explain the variables. Moreover, the explanatory research design and quantitative data collection approach formed the methodology adopted in the study. In addition, a validated semistructured interview questionnaire was used as a research instrument in the study. The multistage, stratify, purposive and convenience sampling techniques were applied to select 6 research sites and 386 research participants for the study. Three research objectives were stated and tested using descriptive, Principal Component Analysis (PCA) to profile the risk and logit regression statistics. The results of statistical analysis show different level of cross tabulation between MFS and education level, all the 6 different locations, individual age range, job type, and average income of individual. Analysis revealed that age and income level of individuals have the highest relationship with the use of MFS. The statistical analysis used was the logistic regression. Pool of effort of all the stake holders in financial services sector should focus on including the low income earners and the technology should be simple enough for the use of the older generation.
- Full Text:
- Date Issued: 2019
- Authors: Aderibigbe, Ifeoluwa A.I
- Date: 2019
- Subjects: Mobile commerce Finance
- Language: English
- Type: Thesis , Masters , MCom (Economics)
- Identifier: http://hdl.handle.net/10353/13281 , vital:39630
- Description: The study investigated risk and adoption of mobile financial services among some users in selected municipalities within the Eastern Cape Province, using the theory of reason action, technology acceptance model and the theory of expected utility and risk aversion to explain the variables. Moreover, the explanatory research design and quantitative data collection approach formed the methodology adopted in the study. In addition, a validated semistructured interview questionnaire was used as a research instrument in the study. The multistage, stratify, purposive and convenience sampling techniques were applied to select 6 research sites and 386 research participants for the study. Three research objectives were stated and tested using descriptive, Principal Component Analysis (PCA) to profile the risk and logit regression statistics. The results of statistical analysis show different level of cross tabulation between MFS and education level, all the 6 different locations, individual age range, job type, and average income of individual. Analysis revealed that age and income level of individuals have the highest relationship with the use of MFS. The statistical analysis used was the logistic regression. Pool of effort of all the stake holders in financial services sector should focus on including the low income earners and the technology should be simple enough for the use of the older generation.
- Full Text:
- Date Issued: 2019
An assessment of the implementation of the Employment Equity Act 55 of 1998 by the Eastern Cape Department of Education: the case of the provincial office in Zwelitsha
- Authors: Sikhotha, Mvumelwano
- Date: 2019
- Subjects: Employment equity
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10948/44743 , vital:38162
- Description: Before 1994, South Africa was under colonialism and apartheid government. The South African work environment was characterised by many cases of injustices, unfair treatment, unfair discrimination in employment, which led to continuous industrial actions. With the advent of democracy in South Africa in the early 1990s, many labour laws were passed to address labour disputesand to make the labour environment governable and conducive for maximum performance.
- Full Text: false
- Date Issued: 2019
- Authors: Sikhotha, Mvumelwano
- Date: 2019
- Subjects: Employment equity
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10948/44743 , vital:38162
- Description: Before 1994, South Africa was under colonialism and apartheid government. The South African work environment was characterised by many cases of injustices, unfair treatment, unfair discrimination in employment, which led to continuous industrial actions. With the advent of democracy in South Africa in the early 1990s, many labour laws were passed to address labour disputesand to make the labour environment governable and conducive for maximum performance.
- Full Text: false
- Date Issued: 2019
Corporate Social Responsibility as a strategy for community development in the Eastern Cape Province: The Case of Volkswagen in Uitenhage
- Authors: Mutongoza, Bonginkosi Hardy
- Date: 2019
- Subjects: Social responsibility of business Community development
- Language: English
- Type: Thesis , Masters , MCom (Development Studies)
- Identifier: http://hdl.handle.net/10353/16963 , vital:40789
- Description: The turn of the new millennium has brought with it a heightened emphasis on Corporate Social Responsibility (CSR), particularly more recently in the global South where underdevelopment is more prevalent. While corporates continue to be viewed as more better-placed than global South governments in the attempt to deal with underdevelopment, this contribution of corporates does not come naturally since their primary focus is making profit. In the case of South Africa, the CSR agenda is regulated primarily by two legal instruments: the B-BBEE Act and the Companies Act. This study set out to determine whether CSR is an effective strategy for community development (CD). The study relied on a qualitative research methodology, employing face-to-face interviews and focus group discussions as the primary sources of data. Data was gathered primarily from two sets of samples: a community sample which comprised of members from wards 47, 50 and 51 in Uitenhage; and a sample comprising of officials from the B-BBEE Commission, the Nelson Mandela Bay Municipality Local Economic Development, and the Volkswagen Community Trust. Participants were purposively sampled in order to save time and resources. The study established that although CSR can be employed for the purposes of achieving community development, there is need for dedicated policies that deal specifically with CSR and set the parameters within which CSR can be carried out. The effectiveness of the CSR agenda in South Africa, thus, relies heavily on the institution of an effective regulatory framework.
- Full Text:
- Date Issued: 2019
- Authors: Mutongoza, Bonginkosi Hardy
- Date: 2019
- Subjects: Social responsibility of business Community development
- Language: English
- Type: Thesis , Masters , MCom (Development Studies)
- Identifier: http://hdl.handle.net/10353/16963 , vital:40789
- Description: The turn of the new millennium has brought with it a heightened emphasis on Corporate Social Responsibility (CSR), particularly more recently in the global South where underdevelopment is more prevalent. While corporates continue to be viewed as more better-placed than global South governments in the attempt to deal with underdevelopment, this contribution of corporates does not come naturally since their primary focus is making profit. In the case of South Africa, the CSR agenda is regulated primarily by two legal instruments: the B-BBEE Act and the Companies Act. This study set out to determine whether CSR is an effective strategy for community development (CD). The study relied on a qualitative research methodology, employing face-to-face interviews and focus group discussions as the primary sources of data. Data was gathered primarily from two sets of samples: a community sample which comprised of members from wards 47, 50 and 51 in Uitenhage; and a sample comprising of officials from the B-BBEE Commission, the Nelson Mandela Bay Municipality Local Economic Development, and the Volkswagen Community Trust. Participants were purposively sampled in order to save time and resources. The study established that although CSR can be employed for the purposes of achieving community development, there is need for dedicated policies that deal specifically with CSR and set the parameters within which CSR can be carried out. The effectiveness of the CSR agenda in South Africa, thus, relies heavily on the institution of an effective regulatory framework.
- Full Text:
- Date Issued: 2019
Synthesis, characterization and anticancer studies of Oxovanadium(iv) Dithiocarbamate complexes
- Authors: Hlobo, Priscilla Vuyiswa
- Date: 2019
- Subjects: Inorganic compounds -- Synthesis Chemistry, Inorganic
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/19131 , vital:39880
- Description: Eight new oxovanadium(IV) dithiocarbamate complexes, formed by the interaction of vanadyl sulfate pentahydrate and as-synthesized dithiocarbamate ligands, potassium N-morpholine-4- dithiocarbamate ligand (L1), potassium N-piperidinedithiocarbamate (L2), potassium N-(4- methoxyphenyl)dithiocarbamate ligand (L3), potassium N-diallyldithiocarbamate ligand (L4), potassium N-phenyldithiocarbamate ligand (L5), potassium N-dibenzylminedithiocarbamate ligand (L6), potassium N-(4-methylphenyl)dithiocarbamate ligand (L7), N-(1Himidazoledithiocarbamate) fluoride ligand (L8) in aqueous ethanol are described. The resulting complexes were elemental analyses, molar conductance, infrared, electronic, and nuclear magnetic resonance spectral studies. The spectral studies confirmed the formation of the ligands and complexes. Four complexes [VO(L1)2], [VO(L3)2], [VO(L6)2], and [VO(L8)2] derived from potassium N-morpholine-4-dithiocarbamate ligand (L1), potassium N-(4- methoxyphenyl)dithiocarbamate ligand (L3), potassium N-dibenzylminedithiocarbamate ligand (L6), and N-(1H-imidazoledithiocarbamate) fluoride ligand (L8) were characterized using cyclic voltammetry, to study their electrochemical behavior. Square pyramid oxovanadium(IV) complexes were proposed with the metal ion coordinated to two bidentate dithiocarbamate ligands through sulphur to complete its square pyramidal geometry. The anticancer screening of four oxovanadium(IV) dithiocarbamate complexes [VO(L1)2], [VO(L3)2], [VO(L6)2], and [VO(L8)2] are described.
- Full Text:
- Date Issued: 2019
- Authors: Hlobo, Priscilla Vuyiswa
- Date: 2019
- Subjects: Inorganic compounds -- Synthesis Chemistry, Inorganic
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/19131 , vital:39880
- Description: Eight new oxovanadium(IV) dithiocarbamate complexes, formed by the interaction of vanadyl sulfate pentahydrate and as-synthesized dithiocarbamate ligands, potassium N-morpholine-4- dithiocarbamate ligand (L1), potassium N-piperidinedithiocarbamate (L2), potassium N-(4- methoxyphenyl)dithiocarbamate ligand (L3), potassium N-diallyldithiocarbamate ligand (L4), potassium N-phenyldithiocarbamate ligand (L5), potassium N-dibenzylminedithiocarbamate ligand (L6), potassium N-(4-methylphenyl)dithiocarbamate ligand (L7), N-(1Himidazoledithiocarbamate) fluoride ligand (L8) in aqueous ethanol are described. The resulting complexes were elemental analyses, molar conductance, infrared, electronic, and nuclear magnetic resonance spectral studies. The spectral studies confirmed the formation of the ligands and complexes. Four complexes [VO(L1)2], [VO(L3)2], [VO(L6)2], and [VO(L8)2] derived from potassium N-morpholine-4-dithiocarbamate ligand (L1), potassium N-(4- methoxyphenyl)dithiocarbamate ligand (L3), potassium N-dibenzylminedithiocarbamate ligand (L6), and N-(1H-imidazoledithiocarbamate) fluoride ligand (L8) were characterized using cyclic voltammetry, to study their electrochemical behavior. Square pyramid oxovanadium(IV) complexes were proposed with the metal ion coordinated to two bidentate dithiocarbamate ligands through sulphur to complete its square pyramidal geometry. The anticancer screening of four oxovanadium(IV) dithiocarbamate complexes [VO(L1)2], [VO(L3)2], [VO(L6)2], and [VO(L8)2] are described.
- Full Text:
- Date Issued: 2019
To explore the Reconstruction Development Programme housing system in South Africa and its full potential relating to the system itself, the design, government’s role and the challenges encountered in its implementation: The Case of Buffalo City Metropolitan Municipality, Eastern Cape
- Authors: Mvunge, Nathunathi Mvunge
- Date: 2019
- Subjects: Housing -- South Africa -- Eastern Cape Human services -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/13782 , vital:39711
- Description: The issue of housing in South Africa presents a challenge confronting many citizens. As such, this dissertation seeks to identify the challenges faced by the Buffalo City Metropolitan Municipality in its implementation of the RDP Housing Scheme, to assess how the housing challenges in the BCMM differ from those in other municipalities, to identify the measures taken by the Buffalo City Metropolitan Municipality to address the challenges encountered in the implementation of the RDP Housing Scheme and to give possible recommendations that address the challenges encountered in the implementation of the RDP Housing Scheme in BCMM. The study makes use of qualitative research in the form of in-depth interviews, focus group discussions, observations and relevant secondary literature to collect data from the Buffalo City Metropolitan Municipality and from citizens residing in Amalinda and Scenery Park RDP houses. The findings of the study show that the majority of the occupants of RDP houses in both Amalinda and Scenery Park are not satisfied with the quality of the houses mainly in terms of their sizes and space. The government has limited resources and is not able to provide enough good quality houses to the applicant’s needs. In addition, the study reveals that there are bureaucratic (red tape) delays in the implementation of the RDP and that the government does not work together with or consult with the beneficiaries of the RDP Housing scheme sufficiently. The study was anchored in the Neo-institutional and the growth pole theory. As to recommendations, the study has recommended that the government address the still extant barriers intiated by the apartheid government, by allowing public participation in the implementation of the RDP housing scheme and ensuring that effective screening measures be used to eligible RDP housing occupants.
- Full Text:
- Date Issued: 2019
- Authors: Mvunge, Nathunathi Mvunge
- Date: 2019
- Subjects: Housing -- South Africa -- Eastern Cape Human services -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/13782 , vital:39711
- Description: The issue of housing in South Africa presents a challenge confronting many citizens. As such, this dissertation seeks to identify the challenges faced by the Buffalo City Metropolitan Municipality in its implementation of the RDP Housing Scheme, to assess how the housing challenges in the BCMM differ from those in other municipalities, to identify the measures taken by the Buffalo City Metropolitan Municipality to address the challenges encountered in the implementation of the RDP Housing Scheme and to give possible recommendations that address the challenges encountered in the implementation of the RDP Housing Scheme in BCMM. The study makes use of qualitative research in the form of in-depth interviews, focus group discussions, observations and relevant secondary literature to collect data from the Buffalo City Metropolitan Municipality and from citizens residing in Amalinda and Scenery Park RDP houses. The findings of the study show that the majority of the occupants of RDP houses in both Amalinda and Scenery Park are not satisfied with the quality of the houses mainly in terms of their sizes and space. The government has limited resources and is not able to provide enough good quality houses to the applicant’s needs. In addition, the study reveals that there are bureaucratic (red tape) delays in the implementation of the RDP and that the government does not work together with or consult with the beneficiaries of the RDP Housing scheme sufficiently. The study was anchored in the Neo-institutional and the growth pole theory. As to recommendations, the study has recommended that the government address the still extant barriers intiated by the apartheid government, by allowing public participation in the implementation of the RDP housing scheme and ensuring that effective screening measures be used to eligible RDP housing occupants.
- Full Text:
- Date Issued: 2019
Attitudes of community stakeholders towards stigmatization of people living with HIV/AIDS in Highland View, linked to St Patrick's Clinic, Bizana, Eastern Cape
- Authors: Nkalane, Athenkosi
- Date: 2017
- Subjects: AIDS (Disease) -- Social aspects -- South Africa -- Eastern Cape , HIV-positive persons -- South Africa -- Eastern Cape , Stigma (Social psychology)
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/9446 , vital:34352
- Description: The researcher attempted to investigate attitudes of community stakeholders towards stigmatization of people living with HIV/AIDS (PLWHA). This is because people living with HIV/AIDS are usually subjected to negative and positive attitudes in South African communities. The study made use of a case study as a specific research design which was explorative and descriptive. The study employed in-depth interviews, focus group discussions and secondary data sources to collect data. The study was a cross-sectional and adopted a non-probability sampling methodology, but specifically purposive technique. The study used 25 participants who consisted of 12 PLWHA, 5 nurses, and 8 selected community members. The data were analyzed through content thematic analysis. The findings that emanated from the study were: awareness of stigmatizing attitudes subjected to people living with HIV/AIDS (PLWHA); the attitudes displayed towards PLWHA, the drivers of stigma; the impact of stigma on PLWHA; PLWHA suffers immense psychosocial deficit; PLWHA face a state of abject poverty; PLWHA faces Psycho-emotional deficit; the secrecy surrounding the virus forms a fertile ground for infection; fear of contagion; stigma confounds chances of HIV/AIDS disclosure and issues of confidentiality. The study recommended that: the government should prioritize the PLWHA’s human rights; adoption of social media platforms to raise awareness and education of HIV/AIDS; collaboration between the Department of Health and the Department of Traditional affairs; invention of a youth-based psycho-emotional programme; and establishment of in-depth community supported interventions.
- Full Text:
- Date Issued: 2017
- Authors: Nkalane, Athenkosi
- Date: 2017
- Subjects: AIDS (Disease) -- Social aspects -- South Africa -- Eastern Cape , HIV-positive persons -- South Africa -- Eastern Cape , Stigma (Social psychology)
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/9446 , vital:34352
- Description: The researcher attempted to investigate attitudes of community stakeholders towards stigmatization of people living with HIV/AIDS (PLWHA). This is because people living with HIV/AIDS are usually subjected to negative and positive attitudes in South African communities. The study made use of a case study as a specific research design which was explorative and descriptive. The study employed in-depth interviews, focus group discussions and secondary data sources to collect data. The study was a cross-sectional and adopted a non-probability sampling methodology, but specifically purposive technique. The study used 25 participants who consisted of 12 PLWHA, 5 nurses, and 8 selected community members. The data were analyzed through content thematic analysis. The findings that emanated from the study were: awareness of stigmatizing attitudes subjected to people living with HIV/AIDS (PLWHA); the attitudes displayed towards PLWHA, the drivers of stigma; the impact of stigma on PLWHA; PLWHA suffers immense psychosocial deficit; PLWHA face a state of abject poverty; PLWHA faces Psycho-emotional deficit; the secrecy surrounding the virus forms a fertile ground for infection; fear of contagion; stigma confounds chances of HIV/AIDS disclosure and issues of confidentiality. The study recommended that: the government should prioritize the PLWHA’s human rights; adoption of social media platforms to raise awareness and education of HIV/AIDS; collaboration between the Department of Health and the Department of Traditional affairs; invention of a youth-based psycho-emotional programme; and establishment of in-depth community supported interventions.
- Full Text:
- Date Issued: 2017
Inhalable particulate systems for anti-tubercular drug delivery
- Nkanga, Christian Isalomboto
- Authors: Nkanga, Christian Isalomboto
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/37966 , vital:24720
- Description: Tuberculosis (TB) is a deadly infectious microbial disease that is currently dominating public health concerns. Among the pharmacological issues in the management of TB are the poor bioavailability of some anti-TB drugs, mostly due to the fast first-pass metabolism, and high drug load needed for combination therapy. These result in a lengthy treatment with several adverse effects causing decreased patient compliance. These factors often lead to the therapeutic failure and promote the development of drug resistant strains, justifying the urgent need for new therapeutic strategies. Liposomes are lipid-based particulate vehicles known to be the most clinically appointed drug carriers currently. Liposomal systems are reported to be rapidly engulfed by macrophages - where the mycobacterium often resides. This makes liposomes appropriate vehicles for targeted anti-TB drug delivery. Many research groups have reported the potential of liposomes systems to deliver anti-TB drugs. However, the costly formulation status of liposomes, due the use of expensive synthetic or highly purified natural phospholipids, is a limitation to the treatment of a poverty related infectious disease like TB. The aim of this study was to design and develop liposomes for pulmonary delivery of anti-TB drugs using crude soybean lecithin (CL) and its purirified version. CL is an FDA- approved naturally occurring phospholipid mixture that is quite cheap and readily available. Various liposome batches were prepared using a film hydration method and characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Liposomes composed of CL and cholesterol (Chol) in a 3:1 mass ratio were selected for drug encapsulation based on the following characteristics: polydispersity index (PDI, 0.28), mean particles sizes (PS, 502 nm) and zeta potential (ZP, -56 mV). Isoniazid (INH) was encapsulated as a model drug using a freeze-thaw loading technique and an HPLC method was validated for quantitative analysis. The physicochemical properties of INH-loaded liposomes were comprehensively investigated using thermal, microscopy and spectroscopic techniques. This formulation showed a high encapsulation efficiency (%EE) of 78%, much better than the liposomes made from purified lecithin, 20%. Other characteristics of INH- loaded liposomes, which make them attractive for pulmonary TB therapy, are presented in this dissertation. These include a controlled release of 50% of the encapsulated INH over 12 hours. Finally, rifampicin (RIF) was added as a hydrophobic model drug and several evaluations were conducted on these dual drug-loaded liposomes. Of particular interest, it was noted that the dual drug-loaded liposomes made of CL alone showed the highest %EE (59% for INH and 90% for RIF) compared to those containing Chol or those made of purified lecithin. Surprisingly, the average PS of the dual CL-based liposomes (1114 nm) was in the size range reported for optimum deep lung deposition and macrophage uptake. In addition, the mean ZP of these liposomes (-63 mV) seems to be favourable for their shelf stability and internalization by macrophages. Overall, these findings show that the dual CL-based liposomes developed would be promising for macrophage-targeting pulmonary delivery of anti-TB drugs.
- Full Text:
- Date Issued: 2017
- Authors: Nkanga, Christian Isalomboto
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/37966 , vital:24720
- Description: Tuberculosis (TB) is a deadly infectious microbial disease that is currently dominating public health concerns. Among the pharmacological issues in the management of TB are the poor bioavailability of some anti-TB drugs, mostly due to the fast first-pass metabolism, and high drug load needed for combination therapy. These result in a lengthy treatment with several adverse effects causing decreased patient compliance. These factors often lead to the therapeutic failure and promote the development of drug resistant strains, justifying the urgent need for new therapeutic strategies. Liposomes are lipid-based particulate vehicles known to be the most clinically appointed drug carriers currently. Liposomal systems are reported to be rapidly engulfed by macrophages - where the mycobacterium often resides. This makes liposomes appropriate vehicles for targeted anti-TB drug delivery. Many research groups have reported the potential of liposomes systems to deliver anti-TB drugs. However, the costly formulation status of liposomes, due the use of expensive synthetic or highly purified natural phospholipids, is a limitation to the treatment of a poverty related infectious disease like TB. The aim of this study was to design and develop liposomes for pulmonary delivery of anti-TB drugs using crude soybean lecithin (CL) and its purirified version. CL is an FDA- approved naturally occurring phospholipid mixture that is quite cheap and readily available. Various liposome batches were prepared using a film hydration method and characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Liposomes composed of CL and cholesterol (Chol) in a 3:1 mass ratio were selected for drug encapsulation based on the following characteristics: polydispersity index (PDI, 0.28), mean particles sizes (PS, 502 nm) and zeta potential (ZP, -56 mV). Isoniazid (INH) was encapsulated as a model drug using a freeze-thaw loading technique and an HPLC method was validated for quantitative analysis. The physicochemical properties of INH-loaded liposomes were comprehensively investigated using thermal, microscopy and spectroscopic techniques. This formulation showed a high encapsulation efficiency (%EE) of 78%, much better than the liposomes made from purified lecithin, 20%. Other characteristics of INH- loaded liposomes, which make them attractive for pulmonary TB therapy, are presented in this dissertation. These include a controlled release of 50% of the encapsulated INH over 12 hours. Finally, rifampicin (RIF) was added as a hydrophobic model drug and several evaluations were conducted on these dual drug-loaded liposomes. Of particular interest, it was noted that the dual drug-loaded liposomes made of CL alone showed the highest %EE (59% for INH and 90% for RIF) compared to those containing Chol or those made of purified lecithin. Surprisingly, the average PS of the dual CL-based liposomes (1114 nm) was in the size range reported for optimum deep lung deposition and macrophage uptake. In addition, the mean ZP of these liposomes (-63 mV) seems to be favourable for their shelf stability and internalization by macrophages. Overall, these findings show that the dual CL-based liposomes developed would be promising for macrophage-targeting pulmonary delivery of anti-TB drugs.
- Full Text:
- Date Issued: 2017
Biofuels and rural development: A case study of the Mapfura-Makhura Incubator and small-scale farmers in the Limpopo Province
- Authors: Mothupi, Frans Makwena
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/1488 , vital:20062
- Description: The primary objective of the study is to examine the livelihood impact of biofuel production on small-scale rural farmers participating in the MMI project in the local districts in Limpopo province. The study is theoretically underpinned by the sustainable livelihoods framework which provides a nuanced analysis of the complex nature of poverty and livelihoods. The framework was used to examine how MMI as a structure with its own processes (incubator model) plays a role in creating a means for farmers to have more access to livelihood assets which would help them achieve improved livelihoods outcome. The findings of this study reflect what has already been articulated in literature about small-scale biofuel projects. This study shows that MMI’s incubator plays an important role for 73% of the farmers to access all of the livelihood assets and ultimately improving their farm income and food security. Furthermore, 90% of the participants admitted to have received support from MMI in a number of ways. This includes the provision of farming inputs, labour and access to markets in addition to training, mentoring and coaching. The study also found that despite the overwhelming support, both MMI and farmers face a number of challenges. Farmers still lack adequate farming inputs, transport, access to markets and vulnerability to natural disasters. MMI faces challenges in raising funds to provide inputs to all their incubatees and lack of adequate mechanization. Lack of transportation affects both farmers and MMI in that farmers find it difficult to access MMI service. In the same light, MMI has found it difficult to reach farmers for post-incubation, coaching and mentoring or delivering inputs; this can be challenging and a costly process. MMI’s biofuel production project has the capability for improving rural livelihoods through agriculture. The study concludes by recommending that MMI should improve its own capacity in order for them to better the lives of the farmers they assist. This study is significant for contributing to a field which has received less academic and research attention in South Africa. Its scholarly contribution will enhance the existing body of knowledge on biofuels and rural development in South Africa
- Full Text:
- Date Issued: 2016
- Authors: Mothupi, Frans Makwena
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/1488 , vital:20062
- Description: The primary objective of the study is to examine the livelihood impact of biofuel production on small-scale rural farmers participating in the MMI project in the local districts in Limpopo province. The study is theoretically underpinned by the sustainable livelihoods framework which provides a nuanced analysis of the complex nature of poverty and livelihoods. The framework was used to examine how MMI as a structure with its own processes (incubator model) plays a role in creating a means for farmers to have more access to livelihood assets which would help them achieve improved livelihoods outcome. The findings of this study reflect what has already been articulated in literature about small-scale biofuel projects. This study shows that MMI’s incubator plays an important role for 73% of the farmers to access all of the livelihood assets and ultimately improving their farm income and food security. Furthermore, 90% of the participants admitted to have received support from MMI in a number of ways. This includes the provision of farming inputs, labour and access to markets in addition to training, mentoring and coaching. The study also found that despite the overwhelming support, both MMI and farmers face a number of challenges. Farmers still lack adequate farming inputs, transport, access to markets and vulnerability to natural disasters. MMI faces challenges in raising funds to provide inputs to all their incubatees and lack of adequate mechanization. Lack of transportation affects both farmers and MMI in that farmers find it difficult to access MMI service. In the same light, MMI has found it difficult to reach farmers for post-incubation, coaching and mentoring or delivering inputs; this can be challenging and a costly process. MMI’s biofuel production project has the capability for improving rural livelihoods through agriculture. The study concludes by recommending that MMI should improve its own capacity in order for them to better the lives of the farmers they assist. This study is significant for contributing to a field which has received less academic and research attention in South Africa. Its scholarly contribution will enhance the existing body of knowledge on biofuels and rural development in South Africa
- Full Text:
- Date Issued: 2016
Fatty acid composition, colour stability and lipid oxidation of mince produced from fresh and frozen/thawed fallow deer meat
- Authors: Chido, Chakanya
- Date: 2016
- Subjects: Lipids -- Oxidation Meat -- Preservation Mincemeat
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2479 , vital:27874
- Description: The aim of the study was to determine the fatty acid composition, colour stability and lipid oxidation of fresh mince produced from fallow deer and to evaluate the effect of frozen storage duration on the retail display shelf life of the mince. A total of 31 fallow deer carcasses were used in the study. After cooling for 24hrs, the carcasses were deboned, external fat from the fore and hindquarter muscles removed and individually vacuum packed. For the first trial, seven fallow deer carcasses were used. Meat from the hind and fore-quarters of each carcass was divided into two equal batches per animal. One batch was minced (through a 5 mm die) and packed into oxygen permeable overwraps and refrigerated at 4°C for a period of eight days under retail display conditions. The second batch was vacuum packed and frozen at -20°C for 2 months at the end of which mince was also produced and monitored over an eight-day period under the same conditions that were used for the fresh mince. Colour, pH, lipid and myoglobin stability was determined. Proximate and fatty acid composition was also determined. No differences (P>0.05) were noted between proximate composition of fresh and frozen/thawed minced meat. The lipid content of fallow deer was 2.4 percent (±0.04). Total n3 fatty acids differed (P<0.05) between treatments and decreased with increased storage and display day. There were significant (P<0.05) treatment and time interactions on all measured colour parameters, TBARS and myoglobin forms. Fresh mince was lighter and had higher redness (a*) and yellowness (b*) values than mince from two months frozen stored meat. Hue angle for fresh mince remained stable throughout display whereas it increased for frozen/thawed mince. Fresh mince had lower TBARS values than frozen/thawed mince. Minced meat produced from frozen/thawed deer meat had higher surface met-myoglobin and total met-myoglobin percentages. Surface and total oxy-myoglobin percentage was higher in fresh mince. The first trial clearly showed colour and lipid stability differences between fresh mince and mince from frozen/thawed meat. It also showed that fresh mince has a longer retail display life than mince produced from frozen/thawed meat (six days and four days, respectively). In the second trial, the effects of frozen storage duration on colour and lipid stability were investigated. Twenty-four fallow deer were used. Twelve were harvested in June (6male 6female) and the other twelve in August (6 male 6female) of the same year.Twenty four hours after harvesting, the fore and hindquarter muscles of the carcasses were deboned, vacuum packed and kept at -20°C until October (i.e. 2months and 4months frozen storage period). Upon thawing, the meat was processed into mince following the same procedure used for the first trialand displayed for a fiveday period under retail display conditions. Frozen duration and gender had no effect (P>0.05) on the proximate composition of fallow deer meat. The total amount of saturated fatty acids (SFA) increased and total amount of poly unsaturated fatty acids (PUFA) decreased as frozen duration and display day increased (P<0.05). Frozen duration affected (P<0.01) lipid oxidation and percentage oxy-myoglobin. Mince pH and all colour parameters (L*, a*, b*,hue and chroma) differed (P<0.05) between treatments on day zero and three. Display day was a significant factor (P<0.05) on all measured parameters. By day three all parameters except pH showed signs of extended oxidation and discolouration as evidenced by reduced redness, decreased colour intensity and high TBARS values. This study showed that prolonged frozen storage negatively affects the colour and lipid stability of meat and increases oxidation of PUFAs during frozen storage. However, the study also suggests that although frozen/thawed meat has a shorter retail display shelf life; the proximate composition of the meat remains unchanged.
- Full Text:
- Date Issued: 2016
- Authors: Chido, Chakanya
- Date: 2016
- Subjects: Lipids -- Oxidation Meat -- Preservation Mincemeat
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2479 , vital:27874
- Description: The aim of the study was to determine the fatty acid composition, colour stability and lipid oxidation of fresh mince produced from fallow deer and to evaluate the effect of frozen storage duration on the retail display shelf life of the mince. A total of 31 fallow deer carcasses were used in the study. After cooling for 24hrs, the carcasses were deboned, external fat from the fore and hindquarter muscles removed and individually vacuum packed. For the first trial, seven fallow deer carcasses were used. Meat from the hind and fore-quarters of each carcass was divided into two equal batches per animal. One batch was minced (through a 5 mm die) and packed into oxygen permeable overwraps and refrigerated at 4°C for a period of eight days under retail display conditions. The second batch was vacuum packed and frozen at -20°C for 2 months at the end of which mince was also produced and monitored over an eight-day period under the same conditions that were used for the fresh mince. Colour, pH, lipid and myoglobin stability was determined. Proximate and fatty acid composition was also determined. No differences (P>0.05) were noted between proximate composition of fresh and frozen/thawed minced meat. The lipid content of fallow deer was 2.4 percent (±0.04). Total n3 fatty acids differed (P<0.05) between treatments and decreased with increased storage and display day. There were significant (P<0.05) treatment and time interactions on all measured colour parameters, TBARS and myoglobin forms. Fresh mince was lighter and had higher redness (a*) and yellowness (b*) values than mince from two months frozen stored meat. Hue angle for fresh mince remained stable throughout display whereas it increased for frozen/thawed mince. Fresh mince had lower TBARS values than frozen/thawed mince. Minced meat produced from frozen/thawed deer meat had higher surface met-myoglobin and total met-myoglobin percentages. Surface and total oxy-myoglobin percentage was higher in fresh mince. The first trial clearly showed colour and lipid stability differences between fresh mince and mince from frozen/thawed meat. It also showed that fresh mince has a longer retail display life than mince produced from frozen/thawed meat (six days and four days, respectively). In the second trial, the effects of frozen storage duration on colour and lipid stability were investigated. Twenty-four fallow deer were used. Twelve were harvested in June (6male 6female) and the other twelve in August (6 male 6female) of the same year.Twenty four hours after harvesting, the fore and hindquarter muscles of the carcasses were deboned, vacuum packed and kept at -20°C until October (i.e. 2months and 4months frozen storage period). Upon thawing, the meat was processed into mince following the same procedure used for the first trialand displayed for a fiveday period under retail display conditions. Frozen duration and gender had no effect (P>0.05) on the proximate composition of fallow deer meat. The total amount of saturated fatty acids (SFA) increased and total amount of poly unsaturated fatty acids (PUFA) decreased as frozen duration and display day increased (P<0.05). Frozen duration affected (P<0.01) lipid oxidation and percentage oxy-myoglobin. Mince pH and all colour parameters (L*, a*, b*,hue and chroma) differed (P<0.05) between treatments on day zero and three. Display day was a significant factor (P<0.05) on all measured parameters. By day three all parameters except pH showed signs of extended oxidation and discolouration as evidenced by reduced redness, decreased colour intensity and high TBARS values. This study showed that prolonged frozen storage negatively affects the colour and lipid stability of meat and increases oxidation of PUFAs during frozen storage. However, the study also suggests that although frozen/thawed meat has a shorter retail display shelf life; the proximate composition of the meat remains unchanged.
- Full Text:
- Date Issued: 2016
Mesopredator release and the effectiveness of camera traps for estimating mammal abundances in the Eastern Cape, South Africa
- Authors: Taylor, Jonathan Michael
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3587 , vital:20527
- Description: Remotely operated cameras (camera traps) have become an indispensable tool for many ecologists, particularly those studying rare and elusive animals. A plethora of camera trap makes and models are now commercially available, yet the effects of their varying design features on the quality and quantity of data recorded remains principally unknown. Better understanding of differing camera trap designs is needed before adequate management policies can be implemented, especially when the aim is to protect vulnerable and endangered species such as many carnivores. Habitat loss and human conflict has prompted worldwide declines of apex predator populations. Following this, many smaller predators have undergone population ‘explosions’ due to the lack of top-down forcing, a phenomenon known as mesopredator release. Land use changes in the Eastern Cape of South Africa have caused extensive degradation and fragmentation of the Subtropical Thicket Biome. In addition, coupled with anthropogenic persecution, apex predators including lions (Panthera leo), leopards (P. pardus), and brown hyaenas (Hyaena brunnea) have been extirpated from large areas of their historic range. Removal of these apex predators may provide opportunity for mesopredators, such as black-backed jackals (Canis mesomelas) and caracals (Caracal caracal), to be released from top-down forcing and possibly initiate trophic cascade effects. Therefore, using randomly distributed camera traps, my study aimed to explore the quality and quantity of data collected by different camera trap designs, and to investigate the mesopredator release hypothesis in the Eastern Cape of South Africa. A total of 2,989 trap nights was used to compare camera trap designs. Camera traps with narrow detection zones and fast trigger speeds (≤ 0.25 seconds) recorded a higher diversity of carnivores, but there was no significant difference in the relative abundances of carnivore species recorded by different camera trap models. A total of 19,659 trap nights was used to assess mesopredator relative abundance, occupancy, distribution and daily activity patterns at one site with, and one site without, apex predators. Consistent with the mesopredator release hypothesis, black-backed jackal relative abundance was significantly higher in the absence of apex predators, and this was supported by occupancy analyses. Further, black-backed jackal distribution was significantly concentrated in areas where apex predator activity was low, possibly indicating spatial avoidance. There was no significant difference in caracal relative abundance, occupancy, distribution, or daily activity between sites. These results provide the first indication of mesopredator release of blackbacked jackals in the Eastern Cape. The implications of black-backed jackal release including prey population structure, local extinctions, altered seed dispersal and disease dynamics are discussed.
- Full Text:
- Date Issued: 2016
- Authors: Taylor, Jonathan Michael
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3587 , vital:20527
- Description: Remotely operated cameras (camera traps) have become an indispensable tool for many ecologists, particularly those studying rare and elusive animals. A plethora of camera trap makes and models are now commercially available, yet the effects of their varying design features on the quality and quantity of data recorded remains principally unknown. Better understanding of differing camera trap designs is needed before adequate management policies can be implemented, especially when the aim is to protect vulnerable and endangered species such as many carnivores. Habitat loss and human conflict has prompted worldwide declines of apex predator populations. Following this, many smaller predators have undergone population ‘explosions’ due to the lack of top-down forcing, a phenomenon known as mesopredator release. Land use changes in the Eastern Cape of South Africa have caused extensive degradation and fragmentation of the Subtropical Thicket Biome. In addition, coupled with anthropogenic persecution, apex predators including lions (Panthera leo), leopards (P. pardus), and brown hyaenas (Hyaena brunnea) have been extirpated from large areas of their historic range. Removal of these apex predators may provide opportunity for mesopredators, such as black-backed jackals (Canis mesomelas) and caracals (Caracal caracal), to be released from top-down forcing and possibly initiate trophic cascade effects. Therefore, using randomly distributed camera traps, my study aimed to explore the quality and quantity of data collected by different camera trap designs, and to investigate the mesopredator release hypothesis in the Eastern Cape of South Africa. A total of 2,989 trap nights was used to compare camera trap designs. Camera traps with narrow detection zones and fast trigger speeds (≤ 0.25 seconds) recorded a higher diversity of carnivores, but there was no significant difference in the relative abundances of carnivore species recorded by different camera trap models. A total of 19,659 trap nights was used to assess mesopredator relative abundance, occupancy, distribution and daily activity patterns at one site with, and one site without, apex predators. Consistent with the mesopredator release hypothesis, black-backed jackal relative abundance was significantly higher in the absence of apex predators, and this was supported by occupancy analyses. Further, black-backed jackal distribution was significantly concentrated in areas where apex predator activity was low, possibly indicating spatial avoidance. There was no significant difference in caracal relative abundance, occupancy, distribution, or daily activity between sites. These results provide the first indication of mesopredator release of blackbacked jackals in the Eastern Cape. The implications of black-backed jackal release including prey population structure, local extinctions, altered seed dispersal and disease dynamics are discussed.
- Full Text:
- Date Issued: 2016
Selfhood, identity and madness in the works of Milan Kundera and Peter Carey
- Authors: Graven, Ashley Holm
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3904 , vital:20554
- Description: Despite all the critical attention Milan Kundera’s and Peter Carey’s fiction has received, relatively little has been said about the way in which these authors problematise selfhood. In this study, I argue that these two writers share a preoccupation with the strictures placed on the individual by his/her location in language and discourse. I show that they deconstruct subjectivity with a view to intimating the possibility of momentarily transcending discursive control, and thereby inhabiting authentic selfhood. In addition, I demonstrate that both authors draw attention to the nature of language through their thematisation of madness, and I then trace the implications of this nexus between language and madness for the reader, who of course is a subject in language. My contention in this regard is that Carey and Kundera seek to instil in the reader a self-reflexive awareness of the ways in which his/her location in language shapes his/her perception of others. In turn, this awareness charges the reader with the responsibility of questioning his/her judgements, and thereby enables him/her to negotiate a measure of authenticity from his/her position in language.
- Full Text:
- Date Issued: 2016
- Authors: Graven, Ashley Holm
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3904 , vital:20554
- Description: Despite all the critical attention Milan Kundera’s and Peter Carey’s fiction has received, relatively little has been said about the way in which these authors problematise selfhood. In this study, I argue that these two writers share a preoccupation with the strictures placed on the individual by his/her location in language and discourse. I show that they deconstruct subjectivity with a view to intimating the possibility of momentarily transcending discursive control, and thereby inhabiting authentic selfhood. In addition, I demonstrate that both authors draw attention to the nature of language through their thematisation of madness, and I then trace the implications of this nexus between language and madness for the reader, who of course is a subject in language. My contention in this regard is that Carey and Kundera seek to instil in the reader a self-reflexive awareness of the ways in which his/her location in language shapes his/her perception of others. In turn, this awareness charges the reader with the responsibility of questioning his/her judgements, and thereby enables him/her to negotiate a measure of authenticity from his/her position in language.
- Full Text:
- Date Issued: 2016
Study into the synthesis, characterisation and applications of Vanadium-based metal organic frameworks, using 1, 2, 4, 5-benzenetetracarboxylic acid
- Authors: Feldmann, Wesley
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/55245 , vital:26680
- Description: This study focussed on the synthesis, characterisation and catalytic application of synthesised vanadium-based Metal-Organic Frameworks using 1,2,4,5-benzenetetracarboxylic acid as a ligand. A number of synthetic methods were tested in multiple attempts to synthesise a V-MOF, these included; ambient, gel, reflux and solvothermal methods of synthesis. Two products of interest were identified, an ambient synthesis produced a vanadium-based complex with the empirical formula: V2O2(Na2H2B4C).6H2O (RU-V2) and a solvothermal synthesis produced a MOF with the empirical formula: V2O2(H2O)2(B4C) (RU-V1). Both products were characterised using elemental analysis, infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry and X-ray powder diffraction. The catalytic activity of these products was tested, alongside the activity of the solid decavanadate ion, for the conversion of cyclohexene to cyclohexene oxide. The decavanadate ion was included to determine if the ion was catalytically active in the solid state, to potentially be used in the construction of a future MOF or V-complex. The reaction for the conversion of cyclohexene to cyclohexene oxide was chosen, as it has been previously conducted using a V-MOF and was found to be successful. The product of the reaction, the epoxide: cyclohexene oxide, is a very useful precursor for a number of reactions involved in the pharmaceutical industry, so developing catalysts which are able to convert cyclohexene to the epoxide with high yields and selectivities are well sought after in industry. The results of the catalytic reactions were varied, as the materials exhibited high yields and selectivities to the epoxide, but these results were only obtained when water was present in the reaction mixture. Water was able to bring about the cleavage of the bonds between the metal and ligand in a highly coordinated framework, at a faster rate than other solvents, such as decane. This ultimately leads to the structural decomposition of the entire complex or framework, depending upon the reaction time. The use of water was a double edged sword in that it was required to initiate the catalytic reaction, but was also the reason that the catalytic materials were noted to decompose over time. The solid decavanadate ion was only noted to exhibit homogeneous activity by dissolving into the small volume of water present in the reaction mixture. The study proved that using a multidentate ligand such as 1,2,4,5-benzenetetracarboxylic acid yielded products which were highly coordinated in nature and would therefore not have large open spaces associated with them, which is commonly observed with other MOFs. Instead the closed nature of the synthesised complexes and frameworks offered a different environment for catalytic reactions, where the small pores/channels had a controlling and inhibiting effect on the reaction. The conversion of cyclohexene to the epoxide is accompanied with a number of undesired side products, so when using the synthesised closed-natured MOF, it was found that there was a greater selectivity for the epoxide over other potential products. This indicates that close natured MOFs may find application in catalytic reactions which require high selectivities for a particular product.
- Full Text:
- Date Issued: 2016
- Authors: Feldmann, Wesley
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/55245 , vital:26680
- Description: This study focussed on the synthesis, characterisation and catalytic application of synthesised vanadium-based Metal-Organic Frameworks using 1,2,4,5-benzenetetracarboxylic acid as a ligand. A number of synthetic methods were tested in multiple attempts to synthesise a V-MOF, these included; ambient, gel, reflux and solvothermal methods of synthesis. Two products of interest were identified, an ambient synthesis produced a vanadium-based complex with the empirical formula: V2O2(Na2H2B4C).6H2O (RU-V2) and a solvothermal synthesis produced a MOF with the empirical formula: V2O2(H2O)2(B4C) (RU-V1). Both products were characterised using elemental analysis, infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry and X-ray powder diffraction. The catalytic activity of these products was tested, alongside the activity of the solid decavanadate ion, for the conversion of cyclohexene to cyclohexene oxide. The decavanadate ion was included to determine if the ion was catalytically active in the solid state, to potentially be used in the construction of a future MOF or V-complex. The reaction for the conversion of cyclohexene to cyclohexene oxide was chosen, as it has been previously conducted using a V-MOF and was found to be successful. The product of the reaction, the epoxide: cyclohexene oxide, is a very useful precursor for a number of reactions involved in the pharmaceutical industry, so developing catalysts which are able to convert cyclohexene to the epoxide with high yields and selectivities are well sought after in industry. The results of the catalytic reactions were varied, as the materials exhibited high yields and selectivities to the epoxide, but these results were only obtained when water was present in the reaction mixture. Water was able to bring about the cleavage of the bonds between the metal and ligand in a highly coordinated framework, at a faster rate than other solvents, such as decane. This ultimately leads to the structural decomposition of the entire complex or framework, depending upon the reaction time. The use of water was a double edged sword in that it was required to initiate the catalytic reaction, but was also the reason that the catalytic materials were noted to decompose over time. The solid decavanadate ion was only noted to exhibit homogeneous activity by dissolving into the small volume of water present in the reaction mixture. The study proved that using a multidentate ligand such as 1,2,4,5-benzenetetracarboxylic acid yielded products which were highly coordinated in nature and would therefore not have large open spaces associated with them, which is commonly observed with other MOFs. Instead the closed nature of the synthesised complexes and frameworks offered a different environment for catalytic reactions, where the small pores/channels had a controlling and inhibiting effect on the reaction. The conversion of cyclohexene to the epoxide is accompanied with a number of undesired side products, so when using the synthesised closed-natured MOF, it was found that there was a greater selectivity for the epoxide over other potential products. This indicates that close natured MOFs may find application in catalytic reactions which require high selectivities for a particular product.
- Full Text:
- Date Issued: 2016
The contribution of smallholder agriculture production to food security in rural Zimbabwe : a case study of Masvingo Province
- Authors: Toringepi, Godfrey
- Date: 2016
- Subjects: Farms, Small -- Zimbabwe Agricultural productivity -- Zimbabwe Sustainable agriculture -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/5598 , vital:29350
- Description: Agricultural development is back on the development agenda. Even though the smallholder farmers are in the majority and at the forefront in terms of food production and agriculture being the backbone of the economy of Zimbabwe, there is no clearly defined policy on smallholder agriculture in Zimbabwe. The food insecurity has remained a continuous challenge for the rural poor in Zimbabwe. This study investigated the contribution of smallholder agriculture to food security with particular reference to the Masvingo province. The study employed qualitative method of research entailing extensive review of literature as a method of data collection. The study utilized the modernisation theory and sustainable livelihoods framework to illustrate smallholder agriculture and food security nexus. The study revealed that smallholder agriculture is the best option for addressing food security since agriculture is considered the main livelihood strategy for small scale farmers in Zimbabwe. There is general scholarly consensus that the main cause of food insecurity in Zimbabwe is a decrease in smallholder agriculture productivity. The study revealed that poor infrastructure , limited access to credit, limited access to inputs, poor investment in human development, limited access to markets and harsh climatic conditions weaken the capacity of small scale farmers to improve food security. Key recommendations are that supportive institutions need to be put in place to strengthen the smallholder farmer’s capacity to improve food security in Zimbabwe.
- Full Text:
- Date Issued: 2016
- Authors: Toringepi, Godfrey
- Date: 2016
- Subjects: Farms, Small -- Zimbabwe Agricultural productivity -- Zimbabwe Sustainable agriculture -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/5598 , vital:29350
- Description: Agricultural development is back on the development agenda. Even though the smallholder farmers are in the majority and at the forefront in terms of food production and agriculture being the backbone of the economy of Zimbabwe, there is no clearly defined policy on smallholder agriculture in Zimbabwe. The food insecurity has remained a continuous challenge for the rural poor in Zimbabwe. This study investigated the contribution of smallholder agriculture to food security with particular reference to the Masvingo province. The study employed qualitative method of research entailing extensive review of literature as a method of data collection. The study utilized the modernisation theory and sustainable livelihoods framework to illustrate smallholder agriculture and food security nexus. The study revealed that smallholder agriculture is the best option for addressing food security since agriculture is considered the main livelihood strategy for small scale farmers in Zimbabwe. There is general scholarly consensus that the main cause of food insecurity in Zimbabwe is a decrease in smallholder agriculture productivity. The study revealed that poor infrastructure , limited access to credit, limited access to inputs, poor investment in human development, limited access to markets and harsh climatic conditions weaken the capacity of small scale farmers to improve food security. Key recommendations are that supportive institutions need to be put in place to strengthen the smallholder farmer’s capacity to improve food security in Zimbabwe.
- Full Text:
- Date Issued: 2016
The design of a research centre for the study of indigenous medical plants, Walter Sisulu University, Mthatha
- Authors: Dabula, Xola
- Date: 2016
- Subjects: College buildings , Research institutes -- South Africa -- Eastern Cape -- Designs and plans , Architecture -- Technological innovations -- South Africa -- Eastern Cape , Architecture, Modern
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/18718 , vital:28710
- Description: This treatise is preoccupied with the design of an Indigenous Medicine Research Institute within the region of (the former) underdeveloped Transkei. The interest in the matter developed out of a concern for a medical system which finds itself in jeopardy of depletion due to over-harvesting which is endangering the ecosystem and its dependents. This is as a resultant lack of development due to its informal nature, and loss of impact of traditional knowledge. Indigenous medicine forms part of the cultural, religious, medical and socio-economical back bone of the region, research will create opportunities for the discovery of new medicinal plants and exploring the applications of age-old remedies in contemporary times. Thus developing and promoting indigenous medicine of the region to a wider user group, in a sustainable method which will protect the environment. Architecturally, the design seeks to respond to an in-depth quest to identify the appropriate nurturing of the relationship between learning and the natural environment, while accommodating the necessary programmatic components which will satisfy the needs of the Institute; namely education, conservation and research. Central to the design is the development of an architecture that addresses the fundamental challenges of education, conservation and the research of plants, in a manner that provides opportunities for collaborative learning practices and an interchange between the user-groups and the plants to be studied, resulting in a building that is at harmony with nature. Through this collaboration of the diverse components, an effective scheme has evolved which offers a singular co-operative environment for the indigenous medical system, in a particular effort to transform the learning environment and extend of the knowledge, as a catalyst for further development and reconciliation with nature. Set in the academic context of the Walter Sisulu University Campus, a once major university in Transkei renowned for its medical department, the Research Institute facility re-establishes the University's medical status in a manner that truly represents its region. The built form will integrate itself into the existing campus conditions in a contemporary way that sets up a response which is conducive to the discovery, preservation and sharing of knowledge pertaining to indigenous medicine.
- Full Text:
- Date Issued: 2016
- Authors: Dabula, Xola
- Date: 2016
- Subjects: College buildings , Research institutes -- South Africa -- Eastern Cape -- Designs and plans , Architecture -- Technological innovations -- South Africa -- Eastern Cape , Architecture, Modern
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/18718 , vital:28710
- Description: This treatise is preoccupied with the design of an Indigenous Medicine Research Institute within the region of (the former) underdeveloped Transkei. The interest in the matter developed out of a concern for a medical system which finds itself in jeopardy of depletion due to over-harvesting which is endangering the ecosystem and its dependents. This is as a resultant lack of development due to its informal nature, and loss of impact of traditional knowledge. Indigenous medicine forms part of the cultural, religious, medical and socio-economical back bone of the region, research will create opportunities for the discovery of new medicinal plants and exploring the applications of age-old remedies in contemporary times. Thus developing and promoting indigenous medicine of the region to a wider user group, in a sustainable method which will protect the environment. Architecturally, the design seeks to respond to an in-depth quest to identify the appropriate nurturing of the relationship between learning and the natural environment, while accommodating the necessary programmatic components which will satisfy the needs of the Institute; namely education, conservation and research. Central to the design is the development of an architecture that addresses the fundamental challenges of education, conservation and the research of plants, in a manner that provides opportunities for collaborative learning practices and an interchange between the user-groups and the plants to be studied, resulting in a building that is at harmony with nature. Through this collaboration of the diverse components, an effective scheme has evolved which offers a singular co-operative environment for the indigenous medical system, in a particular effort to transform the learning environment and extend of the knowledge, as a catalyst for further development and reconciliation with nature. Set in the academic context of the Walter Sisulu University Campus, a once major university in Transkei renowned for its medical department, the Research Institute facility re-establishes the University's medical status in a manner that truly represents its region. The built form will integrate itself into the existing campus conditions in a contemporary way that sets up a response which is conducive to the discovery, preservation and sharing of knowledge pertaining to indigenous medicine.
- Full Text:
- Date Issued: 2016
Work engagement ,organizational commitment and perceived organizational support within a South African agricultural organization
- Authors: Van der Byl, Sally Louise
- Date: 2016
- Subjects: Organizational commitment Employee motivation -- Agriculture , Agriculture -- Economic aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/45580 , vital:38915
- Description: As organisations focus on cultivating extraordinary performance and developing human strength, the need for understanding related constructs has increased. Work engagement, organisational commitment and POS are associated with positive experiences in the workplace. By better understanding these constructs within the agricultural industry, agricultural organisations can focus and develop these constructs in order to increase their sustained competitive advantage. A self-report electronic questionnaire was distributed to employees (N = 126) of a large agricultural organisation whose employees are located throughout South Africa. The measuring instrument measured demographic variables, work engagement, organisational commitment and POS. descriptive and inferential statistics were used to analyse the data. The results indicate that both the work engagement and POS constructs are related to affective, normative and overall organisational commitment. A substantial relationship was also established between work engagement and POS. It was also determined that employees with specialised industry skills are more engaged and committed than their colleagues whose skills are not directly related to agriculture.
- Full Text:
- Date Issued: 2016
- Authors: Van der Byl, Sally Louise
- Date: 2016
- Subjects: Organizational commitment Employee motivation -- Agriculture , Agriculture -- Economic aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/45580 , vital:38915
- Description: As organisations focus on cultivating extraordinary performance and developing human strength, the need for understanding related constructs has increased. Work engagement, organisational commitment and POS are associated with positive experiences in the workplace. By better understanding these constructs within the agricultural industry, agricultural organisations can focus and develop these constructs in order to increase their sustained competitive advantage. A self-report electronic questionnaire was distributed to employees (N = 126) of a large agricultural organisation whose employees are located throughout South Africa. The measuring instrument measured demographic variables, work engagement, organisational commitment and POS. descriptive and inferential statistics were used to analyse the data. The results indicate that both the work engagement and POS constructs are related to affective, normative and overall organisational commitment. A substantial relationship was also established between work engagement and POS. It was also determined that employees with specialised industry skills are more engaged and committed than their colleagues whose skills are not directly related to agriculture.
- Full Text:
- Date Issued: 2016
An investigation into how Zimbabwe's Bulawayo viewers negotiate the gay storyline in Generations
- Authors: Khumalo, Senziwani
- Date: 2015
- Subjects: Generations (Television program) , Homosexuality on television , Homosexuality -- Social aspects -- Zimbabwe -- Bulawayo , Homosexuality -- Law and legislation -- Zimbabwe , Homophobia -- Zimbabwe -- Bulawayo , Social psychology -- Zimbabwe -- Bulawayo
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3543 , http://hdl.handle.net/10962/d1017784
- Description: This study seeks to evaluate how aspects of religion, culture, political context, education and class, amongst others, impact on the manner with which Zimbabwe’s Bulawayo residents make sense of media messages which explore issues of homosexuality, as encountered in the soap opera Generations. This is against the backdrop of Zimbabwean legislation, such as the Sexual Deviancy Act, which criminalises homosexuality and the state victimisation of gays and lesbians in this country. The inclusion of homosexual liberties was rejected by all political parties and both public and private media in the recent drafting of a new rule of law. The legislation, including gay rights exclusion in the new constitution, and state action has perpetuated an impression that Zimbabwe is a deeply homophobic society. As a starting point the study examines the claims of the media imperialism thesis which supposes an all-consuming power of western media and next examines Straubhaar’s thesis of ‘cultural proximity’ which argues that there is often a preference for regional media, which is proximate to viewers’ local culture, language and identity. The study explores the prominence of South Africa as a regional media player and that proximate identities with some cultures in that country have played a role in drawing some Bulawayo viewers to South African television, as they feel slighted by Zimbabwean media. Utilising qualitative research methods, the study explores whether or not the representation of gay images on this South African soap opera provides viewers with opportunities for ‘symbolic distancing’. The concept highlights that when people have insight into lifestyles that are different from their own, they use that as a resource to critically analyse their own lives and cultural understandings. The study evaluates if Bulawayo viewers’ sentiments towards homosexuality has been challenged and changed through their interface with the soap opera, Generations.
- Full Text:
- Date Issued: 2015
- Authors: Khumalo, Senziwani
- Date: 2015
- Subjects: Generations (Television program) , Homosexuality on television , Homosexuality -- Social aspects -- Zimbabwe -- Bulawayo , Homosexuality -- Law and legislation -- Zimbabwe , Homophobia -- Zimbabwe -- Bulawayo , Social psychology -- Zimbabwe -- Bulawayo
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3543 , http://hdl.handle.net/10962/d1017784
- Description: This study seeks to evaluate how aspects of religion, culture, political context, education and class, amongst others, impact on the manner with which Zimbabwe’s Bulawayo residents make sense of media messages which explore issues of homosexuality, as encountered in the soap opera Generations. This is against the backdrop of Zimbabwean legislation, such as the Sexual Deviancy Act, which criminalises homosexuality and the state victimisation of gays and lesbians in this country. The inclusion of homosexual liberties was rejected by all political parties and both public and private media in the recent drafting of a new rule of law. The legislation, including gay rights exclusion in the new constitution, and state action has perpetuated an impression that Zimbabwe is a deeply homophobic society. As a starting point the study examines the claims of the media imperialism thesis which supposes an all-consuming power of western media and next examines Straubhaar’s thesis of ‘cultural proximity’ which argues that there is often a preference for regional media, which is proximate to viewers’ local culture, language and identity. The study explores the prominence of South Africa as a regional media player and that proximate identities with some cultures in that country have played a role in drawing some Bulawayo viewers to South African television, as they feel slighted by Zimbabwean media. Utilising qualitative research methods, the study explores whether or not the representation of gay images on this South African soap opera provides viewers with opportunities for ‘symbolic distancing’. The concept highlights that when people have insight into lifestyles that are different from their own, they use that as a resource to critically analyse their own lives and cultural understandings. The study evaluates if Bulawayo viewers’ sentiments towards homosexuality has been challenged and changed through their interface with the soap opera, Generations.
- Full Text:
- Date Issued: 2015
The effect of grain and soya bean-based diets on chicken production, some egg quality traits, and the potential for allergen carryover to eggs and meat
- Authors: Dokora, Adia-En-Michelle
- Date: 2015
- Subjects: Chickens -- Nutrition Chickens --Feeding and feeds Meat -- Quality
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2946 , vital:28192
- Description: This study determined the effect of maize-, whole wheat-, soya bean-based-diets on the growth performance, egg quality and dressing percentage of chickens, as well as the potential for soy and gluten allergen carryover to eggs and meat from chickens. Twenty 36-week-old Lorham White (LW) hens were divided into two groups and kept in individual cages until they reached 39-weeks of age, with water and feed supplied ad libitum. Ten LW hens were fed a maize/soya bean-based diet (T1) and the other ten birds were fed a maize/soya bean-based diet with a 15 percent whole wheat inclusion (T2) for a period of four weeks, with weekly individual hen weights and group feed consumption figures being recorded. After a two-week diet adaptation period, six eggs per treatment group were collected every second day from the LW hens’ to measure egg quality traits. Every third day, over a 29-day period, six eggs per treatment were collected and analysed for the presence of soy, gluten and gluten-derived peptides using allergen specific enzyme linked immunosorbent assays (ELISA) kits. For the broiler trial, a total of 160 Ross 308 mixed sex day old chicks were used in a completely randomized design. Two dietary treatments were assigned to eight cages (replicate) per treatment, with ten birds per cage. The Ross 308 broiler feeding programme consisted of three phases, starter (day 1 to day 10), grower (day 11 to day 20) and finisher (day 21 to day 28). At the beginning of the trial all chicks were fed T1 which contained a maize/soya bean-based diet for a period of 10 days and then eight cages with 10 birds per cage were randomly selected and fed the T2 diet, which contained a maize/soya bean-based diet with a 15 percent whole wheat inclusion, until they reached 28 days of age. Weekly live weights, feed intake, average daily gain and the average daily feed intake were recorded and calculated. At the end of the grower (day 21) and finisher phase (day 28), one broiler bird was selected per cage to have eight (8) birds per treatment and 16 birds per phase that were slaughtered and breast meat samples were analysed in duplicate for the presence of soy and gluten allergens using ELISA kits. The dressing percentage of hot carcasses was also determined at the end of the finisher phase on eight birds per treatment. For LW hens, live weight (LW) at 39 weeks of age, the average daily feed intake (ADFI) and weekly feed intakes (FI) were significantly different (P < 0.05) between treatments with birds on T2 recording higher gains. As birds age in weeks increased, significant differences (P < 0.05) in live weight values were recorded. Egg quality traits measured (shell weight, yolk weight, albumen weight, albumen height and Haugh units) were significantly different (P < 0.05) between treatments, with eggs from hens receiving T1 recording higher mean values. As hens got older, the colour of egg yolk improved, producing eggs with higher b* (yellowness) values and lower L* (lightness) and a* (redness) mean values. The Haugh unit, significantly improved (P < 0.05) as the hens got older, signifying better quality of eggs. For the broiler birds, growth traits measured indicated that there were no significant differences (P > 0.05) in live weight (LW), average daily feed intake (ADFI), weekly feed intake (FI), feed conversion ratio (FCR), cumulative feed intake (CFI) and cumulative gain (CG) between treatments. No significant differences (P > 0.05) between dressing percentage of broilers from the two treatments were observed. As birds grew, significant differences (P < 0.05) in LW, FI, AFI, FCR, and CFI, over a four-week period were recorded. Results of the allergen analyses indicated that soy and gluten allergens were not carried over from feed into eggs and meat of chickens fed a maize/soya bean-based diet and a maize/soya bean-based with a 15 percent whole wheat inclusion, respectively. In conclusion, a maize/soya bean-based diet and maize/soya bean-based diet with a 15 percent whole wheat inclusion that contained soy and gluten allergens, are feed sources that promote and stimulate 36-week-old LW hen and Ross 308 chicken growth.
- Full Text:
- Date Issued: 2015
- Authors: Dokora, Adia-En-Michelle
- Date: 2015
- Subjects: Chickens -- Nutrition Chickens --Feeding and feeds Meat -- Quality
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2946 , vital:28192
- Description: This study determined the effect of maize-, whole wheat-, soya bean-based-diets on the growth performance, egg quality and dressing percentage of chickens, as well as the potential for soy and gluten allergen carryover to eggs and meat from chickens. Twenty 36-week-old Lorham White (LW) hens were divided into two groups and kept in individual cages until they reached 39-weeks of age, with water and feed supplied ad libitum. Ten LW hens were fed a maize/soya bean-based diet (T1) and the other ten birds were fed a maize/soya bean-based diet with a 15 percent whole wheat inclusion (T2) for a period of four weeks, with weekly individual hen weights and group feed consumption figures being recorded. After a two-week diet adaptation period, six eggs per treatment group were collected every second day from the LW hens’ to measure egg quality traits. Every third day, over a 29-day period, six eggs per treatment were collected and analysed for the presence of soy, gluten and gluten-derived peptides using allergen specific enzyme linked immunosorbent assays (ELISA) kits. For the broiler trial, a total of 160 Ross 308 mixed sex day old chicks were used in a completely randomized design. Two dietary treatments were assigned to eight cages (replicate) per treatment, with ten birds per cage. The Ross 308 broiler feeding programme consisted of three phases, starter (day 1 to day 10), grower (day 11 to day 20) and finisher (day 21 to day 28). At the beginning of the trial all chicks were fed T1 which contained a maize/soya bean-based diet for a period of 10 days and then eight cages with 10 birds per cage were randomly selected and fed the T2 diet, which contained a maize/soya bean-based diet with a 15 percent whole wheat inclusion, until they reached 28 days of age. Weekly live weights, feed intake, average daily gain and the average daily feed intake were recorded and calculated. At the end of the grower (day 21) and finisher phase (day 28), one broiler bird was selected per cage to have eight (8) birds per treatment and 16 birds per phase that were slaughtered and breast meat samples were analysed in duplicate for the presence of soy and gluten allergens using ELISA kits. The dressing percentage of hot carcasses was also determined at the end of the finisher phase on eight birds per treatment. For LW hens, live weight (LW) at 39 weeks of age, the average daily feed intake (ADFI) and weekly feed intakes (FI) were significantly different (P < 0.05) between treatments with birds on T2 recording higher gains. As birds age in weeks increased, significant differences (P < 0.05) in live weight values were recorded. Egg quality traits measured (shell weight, yolk weight, albumen weight, albumen height and Haugh units) were significantly different (P < 0.05) between treatments, with eggs from hens receiving T1 recording higher mean values. As hens got older, the colour of egg yolk improved, producing eggs with higher b* (yellowness) values and lower L* (lightness) and a* (redness) mean values. The Haugh unit, significantly improved (P < 0.05) as the hens got older, signifying better quality of eggs. For the broiler birds, growth traits measured indicated that there were no significant differences (P > 0.05) in live weight (LW), average daily feed intake (ADFI), weekly feed intake (FI), feed conversion ratio (FCR), cumulative feed intake (CFI) and cumulative gain (CG) between treatments. No significant differences (P > 0.05) between dressing percentage of broilers from the two treatments were observed. As birds grew, significant differences (P < 0.05) in LW, FI, AFI, FCR, and CFI, over a four-week period were recorded. Results of the allergen analyses indicated that soy and gluten allergens were not carried over from feed into eggs and meat of chickens fed a maize/soya bean-based diet and a maize/soya bean-based with a 15 percent whole wheat inclusion, respectively. In conclusion, a maize/soya bean-based diet and maize/soya bean-based diet with a 15 percent whole wheat inclusion that contained soy and gluten allergens, are feed sources that promote and stimulate 36-week-old LW hen and Ross 308 chicken growth.
- Full Text:
- Date Issued: 2015
Characterization and application of phthalocyanine-magnetic nanoparticle conjugates anchored to electrospun polyamide nanofibers
- Authors: Ledwaba, Mpho
- Date: 2014
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/54610 , vital:26593
- Description: This work presents the syntheses, photophysical and photochemical characterization of zinc tetracarboxyphenoxy phthalocyanine (ZnTCPPc, 3) and its gadolinium oxide nanoparticle conjugate (4). By means of spectroscopic and microscopic characterization, the conjugation of the ZnTCPPc to the silica coated gadolinium oxide nanoparticles (Si-Gd2O3 NPs, 2) through an amide bond was confirmed. The thermal stability, morphology, nanoparticle sizes and their conjugates with the Pc were studied using ThermoGravimetric Analysis (TGA), Fourier Transform Infrared spectroscopy (FTIR), Transmission Electron Microscopy (TEM) and powder X-ray diffractometry (XRD). Conjugation of ZnTCPPc to the magnetic nanoparticles, proved to have a negligible effect on the photophysical parameters of the phthalocyanine, where a slight decrease in fluorescence and triplet quantum yields and lifetimes was observed. The singlet oxygen quantum yield, however, increased slightly upon conjugation, suggesting that the overall efficiency of the ZnTCPPc as a photosensitizer had improved. Physical mixing of the ZnTCPPc and the silica-coated gadolinium nanoparticles also showed an improvement in the singlet oxygen quantum yield and triplet lifetime, also showing an enhanced efficiency for the photosensitizer and therefore photocatalysis. ZnTCPPc (3) alone and the Pc-gadolinium oxide nanoparticle conjugate (4) were therefore electrospun into nanofibers to create a solid support. The fibers were characterized and their diameter sizes and composition was studied confirming the incorporation of the phthalocyanine and gadolinium oxide nanoparticle. Increased singlet oxygen generation resulted in increased Photodegradation of the environmental pollutant Orange G and the fibers were found to be more efficient as photocatalysts compared to the photosensitizer in solution. The nanomaterial may therefore be applied to the photodegradation of Orange G.
- Full Text:
- Date Issued: 2014
- Authors: Ledwaba, Mpho
- Date: 2014
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/54610 , vital:26593
- Description: This work presents the syntheses, photophysical and photochemical characterization of zinc tetracarboxyphenoxy phthalocyanine (ZnTCPPc, 3) and its gadolinium oxide nanoparticle conjugate (4). By means of spectroscopic and microscopic characterization, the conjugation of the ZnTCPPc to the silica coated gadolinium oxide nanoparticles (Si-Gd2O3 NPs, 2) through an amide bond was confirmed. The thermal stability, morphology, nanoparticle sizes and their conjugates with the Pc were studied using ThermoGravimetric Analysis (TGA), Fourier Transform Infrared spectroscopy (FTIR), Transmission Electron Microscopy (TEM) and powder X-ray diffractometry (XRD). Conjugation of ZnTCPPc to the magnetic nanoparticles, proved to have a negligible effect on the photophysical parameters of the phthalocyanine, where a slight decrease in fluorescence and triplet quantum yields and lifetimes was observed. The singlet oxygen quantum yield, however, increased slightly upon conjugation, suggesting that the overall efficiency of the ZnTCPPc as a photosensitizer had improved. Physical mixing of the ZnTCPPc and the silica-coated gadolinium nanoparticles also showed an improvement in the singlet oxygen quantum yield and triplet lifetime, also showing an enhanced efficiency for the photosensitizer and therefore photocatalysis. ZnTCPPc (3) alone and the Pc-gadolinium oxide nanoparticle conjugate (4) were therefore electrospun into nanofibers to create a solid support. The fibers were characterized and their diameter sizes and composition was studied confirming the incorporation of the phthalocyanine and gadolinium oxide nanoparticle. Increased singlet oxygen generation resulted in increased Photodegradation of the environmental pollutant Orange G and the fibers were found to be more efficient as photocatalysts compared to the photosensitizer in solution. The nanomaterial may therefore be applied to the photodegradation of Orange G.
- Full Text:
- Date Issued: 2014
Distribution of iron-titanium oxides in the vanadiferous main magnetite seam of the upper zone : Northern limb, Bushveld complex
- Authors: Gwatinetsa, Demand
- Date: 2014
- Subjects: Igneous rocks -- South Africa -- Bushveld Complex , Sulfide minerals -- South Africa -- Bushveld Complex , Vanadium -- South Africa -- Bushveld Complex , Titanium dioxide -- South Africa -- Bushveld Complex , Ferric oxide -- South Africa -- Bushveld Complex , Geology -- South Africa -- Bushveld Complex , Mineralogy -- South Africa -- Bushveld Complex , Mines and mineral resources -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5063 , http://hdl.handle.net/10962/d1013281
- Description: The main magnetite seam of the Upper Zone of the Rustenburg Layered Suite (SACS, 1980) on the Bushveld Complex is known to host the world‘s largest vanadium bearing titaniferous iron ores. The vanadiferous titanomagnetites, contain vanadium in sufficient concentrations (1.2 - 2.2 per cent V₂O₅) to be considered as resources and vanadium has been mined historically by a number of companies among them Anglo-American, Highveld Steel and Vanadium and VanMag Resources as well as currently by Evraz Highveld Steel and Vanadium Limited of South Africa. The titanomagnetites contain iron ore in the form of magnetite and titanium with concentrations averaging 50-75 per cent FeO and 12-21 per cent TiO₂. The titaniferous iron ores have been historically dismissed as a source of iron and titanium, due to the known difficulties of using iron ore with high titania content in blast furnaces. The economic potential for the extractability of the titaniferous magnetites lies in the capacity of the ores to be separated into iron rich and titanium rich concentrates usually through, crushing, grinding and magnetic separation. The separatability of iron oxides and titanium oxides, is dependent on the nature in which the titanium oxide occurs, with granular ilmenite being the most favourable since it can be separated from magnetite via magnetic separation. Titanium that occurs as finely exsolved lamellae or as iron-titanium oxides with low titania content such as ulvospinel render the potential recoverability of titanium poor. The Upper Zone vanadiferous titanomagnetites contain titanium in various forms varying from discrete granular ilmenite to finely exsolved lamellae as well as occurring as part of the minerals ulvospinel (Fe₂TiO₄) and titanomagnetite (a solid solution series between ulvospinel and magnetite) . Discrete ilmenite constitutes between 3-5 per cent by volume of the massive titanomagnetite ores, and between 5-10 per cent by volume of the magnetite-plagioclase cumulates with more than 50 per cent opaque oxide minerals. The purpose of this research was to investigate the mineralogical setting and distribution of the iron and titanium oxides within the magnetitite layers from top to bottom as well as spatially along a strike length of 2 000m to determine the potential for the titanium to be extracted from the titanomagnetite ores. The titanomagnetites of the Upper Zone of the Bushveld Complex with particular reference to the Northern Limb where this research was conducted contains titanium oxides as discrete ilmenite grains but in low concentrations whose potential for separate economic extraction will be challenging. The highest concentration of titanium in the magnetite ores is not contained in the granular ilmenite, but rather in ulvospinel and titanomagnetite as illustrated by the marked higher concentration of TiO₂ in the massive ores which contain less granular ilmenite in comparison to the disseminated ores which contain 3 to 8 percentage points higher granular ilmenite than the massive ores. On the scale of the main magnetite seam, the TiO₂ content increases with increasing stratigraphic height from being completely absent in the footwall anorthosite. The V₂2O₅ content also increases with stratigraphic height except for in one of the 3 boreholes where it drops with increasing height. The decrease or increase patterns are repeated in every seam. The titanomagnetites of the main magnetite seam display a variety of textures from coarse granular magnetite and ilmenite, to trellis ilmenite lamellae, intergranular ilmenite and magnesian spinels and fine exsolution lamellae of ulvospinel and ferro-magnesian spinels parallel to the magnetite cleavage. The bottom contact of the main magnetite seam is very sharp and there is no titanium or vanadium in the footwall barely 10cm below the contact. Chromium is present in the bottom of the 4 layers that constitute the main magnetite seam and it upwards decreases rapidly. In boreholes P21 and P55, there are slight reversals in the TiO₂ and V₂O₅ content towards the top of the magnetite seams.
- Full Text:
- Date Issued: 2014
- Authors: Gwatinetsa, Demand
- Date: 2014
- Subjects: Igneous rocks -- South Africa -- Bushveld Complex , Sulfide minerals -- South Africa -- Bushveld Complex , Vanadium -- South Africa -- Bushveld Complex , Titanium dioxide -- South Africa -- Bushveld Complex , Ferric oxide -- South Africa -- Bushveld Complex , Geology -- South Africa -- Bushveld Complex , Mineralogy -- South Africa -- Bushveld Complex , Mines and mineral resources -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5063 , http://hdl.handle.net/10962/d1013281
- Description: The main magnetite seam of the Upper Zone of the Rustenburg Layered Suite (SACS, 1980) on the Bushveld Complex is known to host the world‘s largest vanadium bearing titaniferous iron ores. The vanadiferous titanomagnetites, contain vanadium in sufficient concentrations (1.2 - 2.2 per cent V₂O₅) to be considered as resources and vanadium has been mined historically by a number of companies among them Anglo-American, Highveld Steel and Vanadium and VanMag Resources as well as currently by Evraz Highveld Steel and Vanadium Limited of South Africa. The titanomagnetites contain iron ore in the form of magnetite and titanium with concentrations averaging 50-75 per cent FeO and 12-21 per cent TiO₂. The titaniferous iron ores have been historically dismissed as a source of iron and titanium, due to the known difficulties of using iron ore with high titania content in blast furnaces. The economic potential for the extractability of the titaniferous magnetites lies in the capacity of the ores to be separated into iron rich and titanium rich concentrates usually through, crushing, grinding and magnetic separation. The separatability of iron oxides and titanium oxides, is dependent on the nature in which the titanium oxide occurs, with granular ilmenite being the most favourable since it can be separated from magnetite via magnetic separation. Titanium that occurs as finely exsolved lamellae or as iron-titanium oxides with low titania content such as ulvospinel render the potential recoverability of titanium poor. The Upper Zone vanadiferous titanomagnetites contain titanium in various forms varying from discrete granular ilmenite to finely exsolved lamellae as well as occurring as part of the minerals ulvospinel (Fe₂TiO₄) and titanomagnetite (a solid solution series between ulvospinel and magnetite) . Discrete ilmenite constitutes between 3-5 per cent by volume of the massive titanomagnetite ores, and between 5-10 per cent by volume of the magnetite-plagioclase cumulates with more than 50 per cent opaque oxide minerals. The purpose of this research was to investigate the mineralogical setting and distribution of the iron and titanium oxides within the magnetitite layers from top to bottom as well as spatially along a strike length of 2 000m to determine the potential for the titanium to be extracted from the titanomagnetite ores. The titanomagnetites of the Upper Zone of the Bushveld Complex with particular reference to the Northern Limb where this research was conducted contains titanium oxides as discrete ilmenite grains but in low concentrations whose potential for separate economic extraction will be challenging. The highest concentration of titanium in the magnetite ores is not contained in the granular ilmenite, but rather in ulvospinel and titanomagnetite as illustrated by the marked higher concentration of TiO₂ in the massive ores which contain less granular ilmenite in comparison to the disseminated ores which contain 3 to 8 percentage points higher granular ilmenite than the massive ores. On the scale of the main magnetite seam, the TiO₂ content increases with increasing stratigraphic height from being completely absent in the footwall anorthosite. The V₂2O₅ content also increases with stratigraphic height except for in one of the 3 boreholes where it drops with increasing height. The decrease or increase patterns are repeated in every seam. The titanomagnetites of the main magnetite seam display a variety of textures from coarse granular magnetite and ilmenite, to trellis ilmenite lamellae, intergranular ilmenite and magnesian spinels and fine exsolution lamellae of ulvospinel and ferro-magnesian spinels parallel to the magnetite cleavage. The bottom contact of the main magnetite seam is very sharp and there is no titanium or vanadium in the footwall barely 10cm below the contact. Chromium is present in the bottom of the 4 layers that constitute the main magnetite seam and it upwards decreases rapidly. In boreholes P21 and P55, there are slight reversals in the TiO₂ and V₂O₅ content towards the top of the magnetite seams.
- Full Text:
- Date Issued: 2014