Budget Deficits, the Savings Gap and Current Account Deficits in the Southern African Development Community
- Authors: Kopeledi, Alyssa
- Date: 2020
- Subjects: Budget deficits -- South Africa Accounts current
- Language: English
- Type: Thesis , Masters , MCom (Economics)
- Identifier: http://hdl.handle.net/10353/12392 , vital:39259
- Description: This study examines the validity of the triple deficit hypothesis for a selected number of SADC countries, utilising secondary annual data for the period 1996-2018. Based on previous studies and theory, current account deficit was chosen as the dependent variable and budget deficit and the savings gap as the independent variables. The study makes use of both first generation and second-generation unit root tests to examine the time series properties of the data. The empirical results show that the data is integrated of different orders. Kao, Pedroni and Westerlund cointegration tests were carried out to examine the long-term relationship between the variables of interest. The empirical results revealed that there is a long-term relationship between current account deficit, budget deficit s and the savings gap. The long-run model under the Autoregressive Distributed Lag test revealed that, a positive and significant relationship exists between budget deficit and current account deficit at a significance level of 10% and a negative and insignificant relationship exists between savings gap and current account deficit in the long run. This suggests that an improvement in the current account balance in SADC countries requires fiscal stringency
- Full Text:
- Date Issued: 2020
- Authors: Kopeledi, Alyssa
- Date: 2020
- Subjects: Budget deficits -- South Africa Accounts current
- Language: English
- Type: Thesis , Masters , MCom (Economics)
- Identifier: http://hdl.handle.net/10353/12392 , vital:39259
- Description: This study examines the validity of the triple deficit hypothesis for a selected number of SADC countries, utilising secondary annual data for the period 1996-2018. Based on previous studies and theory, current account deficit was chosen as the dependent variable and budget deficit and the savings gap as the independent variables. The study makes use of both first generation and second-generation unit root tests to examine the time series properties of the data. The empirical results show that the data is integrated of different orders. Kao, Pedroni and Westerlund cointegration tests were carried out to examine the long-term relationship between the variables of interest. The empirical results revealed that there is a long-term relationship between current account deficit, budget deficit s and the savings gap. The long-run model under the Autoregressive Distributed Lag test revealed that, a positive and significant relationship exists between budget deficit and current account deficit at a significance level of 10% and a negative and insignificant relationship exists between savings gap and current account deficit in the long run. This suggests that an improvement in the current account balance in SADC countries requires fiscal stringency
- Full Text:
- Date Issued: 2020
Identification of differentially expressed proteins involved in wheat (Triticum aestivum) resistance against Russian Wheat Aphid (Diuraphis noxia) SA2 using SWATH-MS analysis
- Authors: Ntlokwana, Sitha Emmanuel
- Date: 2020
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/18872 , vital:42888
- Description: Wheat (Triticum aestivum) is the second most-consumed cereal crop in the world, second only to maize. In South Africa it is mainly produced in three provinces; the Free State, Western Cape, and the Northen Cape. The average total land area used for wheat cultivation in these three Provinces, is 533 000 hectares, with a resultant annual production of between 1.3 to 2 million tons. The total wheat requirement in South Africa is currently 2.7 million tons according to the production of wheat guidelines published by the Department of Agriculture, Forestry and Fisheries, which is higher than the total annual production. One of the primary reasons that contribute to the lower production levels is insect and pest infestation, in particular, the Russian wheat aphid (Diurophis noxis), which can result in crop loss of up to sixty percent. Russian wheat aphids (RWA) are invasive insects that feed on the phloem of the plant through their specialised thin stylet-like mouthparts and release toxic agents contained in their saliva during feeding, which disrupt cellular functions inside the host plant. This damage leads to symptoms like; chlorosis, necrosis, wilting, stunting and curling of leaves, also known as leaf rolling. This study aimed to identify differentially expressed proteins in resistant and susceptible wheat (Triticum aestivum) cultivars during Russian wheat aphid Biotype South African 2 (RWA-SA2) infestation, in order to identify proteins involved in the wheat resistant mechanism against RWA-SA2. Two wheat cultivars SST398 (resistant to RWA-SA2) and SST356 (susceptible to RWA-SA2) were used, and a total number of 126 plants were planted and divided according to four different harvest times (Control day 0; day 5; day 7 and day 12). The wheat plants were infested with approximately 10 aphids per plant at the three-leaf stage, and placed within an insect cage inside a growth chamber (Conviron, Winnipeg, Canada) set at 24ºC, light intensity of 352 µmol.m-2.sec-1, ambient CO2 levels (410 ppm) and humidity of 60% with a 16h/8h day/night cycle. Wheat leaves were harvested at various time frames, and total protein extraction was performed. The protein samples were reduced with 10 mM dithiothreitol (DTT) and alkylated with 30 mM iodoacetamide (IAA). Sample clean-up and on-bead trypsin digest were performed on megReSyn Hilic columns, over four hours. The resultant peptides were vacuum dried and resuspended in 2% acetonitrile (ACN) before submitting them to LC-MS/MS (SWATH) for analysis. A total number of 611 proteins were differentially expressed, of which 19 were identified to be involved in the resistance response of wheat, and an additional 20 involved in biotic stress responses. This study showed that reactive oxidative species (ROS) such as hydrogen peroxide and hydroxyl radicals (OH-) play a significant role in the early stages of wheat resistance against RWA-SA2 infestation. They are involved in cell wall strengthening, activation of defence genes, involvement of phytohormone signals such as salicylic and jasmonic acid, which also mediates the systemic defences such as, systemic acquired resistance (SAR), leading to the expression of pathogen-related proteins such as (thaumatin-like proteins, oxalate oxidase, defensin, chitinase, and thionins). Although up-regulation of photosynthesis proteins such as (chlorophyll a/b binding protein, photosystem I and II, rubisco and divinyl chlorophyllide a, and 8 vinyl-reductase) were seen on both infested cultivars (susceptible and resistance), higher numbers of these classes of proteins were identified in the resistance cultivar, suggesting that they also play a critical role in resistance. In conclusion, the SWATH analysis used in this study was able to identify numerous proteins involved in the wheat resistance mechanism against RWA-SA2, most of which have not yet been reported to be involved in either biotic stress or RWA-SA2 resistance responses. Future studies are required to biochemically confirm the involvement of these enzymes and proteins the specific metabolic pathways where they are found, in the wheat resistance mechanism against Russian wheat aphid Biotype 2
- Full Text:
- Date Issued: 2020
- Authors: Ntlokwana, Sitha Emmanuel
- Date: 2020
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/18872 , vital:42888
- Description: Wheat (Triticum aestivum) is the second most-consumed cereal crop in the world, second only to maize. In South Africa it is mainly produced in three provinces; the Free State, Western Cape, and the Northen Cape. The average total land area used for wheat cultivation in these three Provinces, is 533 000 hectares, with a resultant annual production of between 1.3 to 2 million tons. The total wheat requirement in South Africa is currently 2.7 million tons according to the production of wheat guidelines published by the Department of Agriculture, Forestry and Fisheries, which is higher than the total annual production. One of the primary reasons that contribute to the lower production levels is insect and pest infestation, in particular, the Russian wheat aphid (Diurophis noxis), which can result in crop loss of up to sixty percent. Russian wheat aphids (RWA) are invasive insects that feed on the phloem of the plant through their specialised thin stylet-like mouthparts and release toxic agents contained in their saliva during feeding, which disrupt cellular functions inside the host plant. This damage leads to symptoms like; chlorosis, necrosis, wilting, stunting and curling of leaves, also known as leaf rolling. This study aimed to identify differentially expressed proteins in resistant and susceptible wheat (Triticum aestivum) cultivars during Russian wheat aphid Biotype South African 2 (RWA-SA2) infestation, in order to identify proteins involved in the wheat resistant mechanism against RWA-SA2. Two wheat cultivars SST398 (resistant to RWA-SA2) and SST356 (susceptible to RWA-SA2) were used, and a total number of 126 plants were planted and divided according to four different harvest times (Control day 0; day 5; day 7 and day 12). The wheat plants were infested with approximately 10 aphids per plant at the three-leaf stage, and placed within an insect cage inside a growth chamber (Conviron, Winnipeg, Canada) set at 24ºC, light intensity of 352 µmol.m-2.sec-1, ambient CO2 levels (410 ppm) and humidity of 60% with a 16h/8h day/night cycle. Wheat leaves were harvested at various time frames, and total protein extraction was performed. The protein samples were reduced with 10 mM dithiothreitol (DTT) and alkylated with 30 mM iodoacetamide (IAA). Sample clean-up and on-bead trypsin digest were performed on megReSyn Hilic columns, over four hours. The resultant peptides were vacuum dried and resuspended in 2% acetonitrile (ACN) before submitting them to LC-MS/MS (SWATH) for analysis. A total number of 611 proteins were differentially expressed, of which 19 were identified to be involved in the resistance response of wheat, and an additional 20 involved in biotic stress responses. This study showed that reactive oxidative species (ROS) such as hydrogen peroxide and hydroxyl radicals (OH-) play a significant role in the early stages of wheat resistance against RWA-SA2 infestation. They are involved in cell wall strengthening, activation of defence genes, involvement of phytohormone signals such as salicylic and jasmonic acid, which also mediates the systemic defences such as, systemic acquired resistance (SAR), leading to the expression of pathogen-related proteins such as (thaumatin-like proteins, oxalate oxidase, defensin, chitinase, and thionins). Although up-regulation of photosynthesis proteins such as (chlorophyll a/b binding protein, photosystem I and II, rubisco and divinyl chlorophyllide a, and 8 vinyl-reductase) were seen on both infested cultivars (susceptible and resistance), higher numbers of these classes of proteins were identified in the resistance cultivar, suggesting that they also play a critical role in resistance. In conclusion, the SWATH analysis used in this study was able to identify numerous proteins involved in the wheat resistance mechanism against RWA-SA2, most of which have not yet been reported to be involved in either biotic stress or RWA-SA2 resistance responses. Future studies are required to biochemically confirm the involvement of these enzymes and proteins the specific metabolic pathways where they are found, in the wheat resistance mechanism against Russian wheat aphid Biotype 2
- Full Text:
- Date Issued: 2020
The relative efficacy of liberation theology and critical solidarity in keeping the SACC to its goals of human welfare and Ecumenical unity in its relationship with the South African state
- Authors: Pongolo, Mziwamadoda
- Date: 2020
- Subjects: Black theology Liberation theology
- Language: English
- Type: Thesis , Masters
- Identifier: http://hdl.handle.net/10353/18269 , vital:42247
- Description: The problem that this study is grappling with is that since the SACC has followed the Critical Solidarity model it is less successful in meeting its goals, to support human welfare and ecumenical solidarity in South Africa. The research will compare the two respective models of relations between SACC and State, that which guided the SACC after the demise of Apartheid that which guided it. First, the research will investigate why the present relationship of Critical Solidarity has proven less effective in achieving its goals. Secondly it will investigate factors accounting for the relative success of the model of relations between SACC and the South African State during the struggle against apartheid, that of Liberation Theology. Secondly, this study will recommend the reconstruction of a more effective model of Critical Solidarity, to remedy present weaknesses, by incorporating factors from the apartheid-era model of Liberation Theology that which serve the goals of ecumenical solidarity and human welfare. The research seeks to address the following questions. What challenges, for the goals of the SACC, of ecumenical solidarity and human welfare, have arisen for the SACC that may be attributed to its adoption of a model of Critical Solidarity in its relationship with the State? What factors conducive to ecumenical solidarity and human welfare are absent from the present model of Critical Solidarity, though they present the preceding model of relations between Church and State as adopted adopted by the SACC during the struggle against apartheid, modeled on Liberation Theology? How might these factors conducive to Church unity and social justice in South Africa be reintroduced in the present model of Critical Solidarity
- Full Text:
- Date Issued: 2020
- Authors: Pongolo, Mziwamadoda
- Date: 2020
- Subjects: Black theology Liberation theology
- Language: English
- Type: Thesis , Masters
- Identifier: http://hdl.handle.net/10353/18269 , vital:42247
- Description: The problem that this study is grappling with is that since the SACC has followed the Critical Solidarity model it is less successful in meeting its goals, to support human welfare and ecumenical solidarity in South Africa. The research will compare the two respective models of relations between SACC and State, that which guided the SACC after the demise of Apartheid that which guided it. First, the research will investigate why the present relationship of Critical Solidarity has proven less effective in achieving its goals. Secondly it will investigate factors accounting for the relative success of the model of relations between SACC and the South African State during the struggle against apartheid, that of Liberation Theology. Secondly, this study will recommend the reconstruction of a more effective model of Critical Solidarity, to remedy present weaknesses, by incorporating factors from the apartheid-era model of Liberation Theology that which serve the goals of ecumenical solidarity and human welfare. The research seeks to address the following questions. What challenges, for the goals of the SACC, of ecumenical solidarity and human welfare, have arisen for the SACC that may be attributed to its adoption of a model of Critical Solidarity in its relationship with the State? What factors conducive to ecumenical solidarity and human welfare are absent from the present model of Critical Solidarity, though they present the preceding model of relations between Church and State as adopted adopted by the SACC during the struggle against apartheid, modeled on Liberation Theology? How might these factors conducive to Church unity and social justice in South Africa be reintroduced in the present model of Critical Solidarity
- Full Text:
- Date Issued: 2020
Investigating the psychological well-being of female students who gave birth during cohabitation
- Authors: Mashabela, Emanuel
- Date: 2020
- Subjects: Unmarried couples
- Language: English
- Type: Thesis , Masters , MSoc. Sci (Psychology)
- Identifier: http://hdl.handle.net/10353/18175 , vital:42239
- Description: This study investigated the psycho-social well-being of female students aged 18 to 27 who gave birth during cohabitation at one of South African university (University of Fort Hare, Alice Campus). It also investigated the challenges those female students face when they try to balance academics with motherhood. The study is underpinned by Ryff (1989) psychological well-being that suggested that psychological well-being is attained by achieving a state of balance affected by both challenging and rewarding life events. Purposive sampling was employed to select participants of the study and in-depth interview was used to generate data. Thematic analysis was engaged to analyse data. The study discovered that the psychological well-being of female students who gave birth during cohabitation is impaired in way that they experienced impaired environmental mastering, impaired good relationship with others, impaired self-acceptance, impaired personal growth however they show resilient. The study found that female students who gave birth during cohabitation are faced with numerous challenges such as discrimination, lack of support, depression in balancing academics with motherhood, lack of attachment with their children including poor academic performance.
- Full Text:
- Date Issued: 2020
- Authors: Mashabela, Emanuel
- Date: 2020
- Subjects: Unmarried couples
- Language: English
- Type: Thesis , Masters , MSoc. Sci (Psychology)
- Identifier: http://hdl.handle.net/10353/18175 , vital:42239
- Description: This study investigated the psycho-social well-being of female students aged 18 to 27 who gave birth during cohabitation at one of South African university (University of Fort Hare, Alice Campus). It also investigated the challenges those female students face when they try to balance academics with motherhood. The study is underpinned by Ryff (1989) psychological well-being that suggested that psychological well-being is attained by achieving a state of balance affected by both challenging and rewarding life events. Purposive sampling was employed to select participants of the study and in-depth interview was used to generate data. Thematic analysis was engaged to analyse data. The study discovered that the psychological well-being of female students who gave birth during cohabitation is impaired in way that they experienced impaired environmental mastering, impaired good relationship with others, impaired self-acceptance, impaired personal growth however they show resilient. The study found that female students who gave birth during cohabitation are faced with numerous challenges such as discrimination, lack of support, depression in balancing academics with motherhood, lack of attachment with their children including poor academic performance.
- Full Text:
- Date Issued: 2020
Factors Affecting Archives and Records Management in The City of Johannesburg Municipality
- Authors: Vula, Malusi
- Date: 2020
- Subjects: Records -- Management
- Language: English
- Type: Thesis , Masters , MSoc. Sci (Library and Information Science)
- Identifier: http://hdl.handle.net/10353/18314 , vital:42251
- Description: This study sought to evaluate the factors that affect the development of archives in the City of Johannesburg Municipality. The use of old records management strategies is posing serious challenges in most African countries and it is affecting the development of archives and records. Literature shows that most municipalities in Southern African countries have not adapted advance records management strategies like Integrated records management and Cloud systems for the realization of benefits of effectiveness and efficiency in records management. The history of Johannesburg municipality and the significance of records management in terms of leveraging effective service delivery raised critical concerns over the development of archives and records management. Proper management of records is the foundation of any government needs to provide services, to fulfil its obligation of accountability towards its citizens and protect their rights. According to the continuum model, the archivists and records managers need to be involved together with information systems designers in the creation of records keeping systems. The records continuum model emphasizes advanced records management strategies and systems in order to ensure the systematic preservation, retrieval and disposal of records. As the records management systems shift from the narrow physical records management as well as imaging into the broader electronic records world there is need for the municipality to embrace more advanced records management strategies like Outsource/Cloud service and integrated records management systems. In order to get a deeper understanding of the factors that affect the development of archives and records management; this study combined both qualitative and quantitative methodologies. The census method was used to select all the 80 members of the records management department in the metropolitan municipality. An in-depth interview schedule was conducted with 4 records managers in order to collect qualitative data. Questionnaires were distributed to 76 personnel in the records management department. Without an operational and effective policy in the department of records, there is no vanguard against unlawful records and archives access and corruption, which is affecting archives development and records management in the long run. The study established although email backups and archiving of files are important strategies, more effective and modern strategies like Integrated Records Management system across the entire organization and the cloud system have not been put in place. This is attributed to the lack of funding and IT expertise. The study concluded that that although training and skills development programs are being ii implemented, skills transfer is not fully taking place due to lack of; equipment, time, managerial support and post-training interventions as well monitoring and evaluation systems. The study recommends an integrated records management system, operationalization of the records management system, effective skills transfer programs, the competency-based model.
- Full Text:
- Date Issued: 2020
- Authors: Vula, Malusi
- Date: 2020
- Subjects: Records -- Management
- Language: English
- Type: Thesis , Masters , MSoc. Sci (Library and Information Science)
- Identifier: http://hdl.handle.net/10353/18314 , vital:42251
- Description: This study sought to evaluate the factors that affect the development of archives in the City of Johannesburg Municipality. The use of old records management strategies is posing serious challenges in most African countries and it is affecting the development of archives and records. Literature shows that most municipalities in Southern African countries have not adapted advance records management strategies like Integrated records management and Cloud systems for the realization of benefits of effectiveness and efficiency in records management. The history of Johannesburg municipality and the significance of records management in terms of leveraging effective service delivery raised critical concerns over the development of archives and records management. Proper management of records is the foundation of any government needs to provide services, to fulfil its obligation of accountability towards its citizens and protect their rights. According to the continuum model, the archivists and records managers need to be involved together with information systems designers in the creation of records keeping systems. The records continuum model emphasizes advanced records management strategies and systems in order to ensure the systematic preservation, retrieval and disposal of records. As the records management systems shift from the narrow physical records management as well as imaging into the broader electronic records world there is need for the municipality to embrace more advanced records management strategies like Outsource/Cloud service and integrated records management systems. In order to get a deeper understanding of the factors that affect the development of archives and records management; this study combined both qualitative and quantitative methodologies. The census method was used to select all the 80 members of the records management department in the metropolitan municipality. An in-depth interview schedule was conducted with 4 records managers in order to collect qualitative data. Questionnaires were distributed to 76 personnel in the records management department. Without an operational and effective policy in the department of records, there is no vanguard against unlawful records and archives access and corruption, which is affecting archives development and records management in the long run. The study established although email backups and archiving of files are important strategies, more effective and modern strategies like Integrated Records Management system across the entire organization and the cloud system have not been put in place. This is attributed to the lack of funding and IT expertise. The study concluded that that although training and skills development programs are being ii implemented, skills transfer is not fully taking place due to lack of; equipment, time, managerial support and post-training interventions as well monitoring and evaluation systems. The study recommends an integrated records management system, operationalization of the records management system, effective skills transfer programs, the competency-based model.
- Full Text:
- Date Issued: 2020
Beef quality, oxidative stability and fatty acid composition of Nguni heifers fed diets with incremental levels of Opuntia ficus-indica (cactus) cladodes
- Authors: Mkhosi, Silungile
- Date: 2020
- Subjects: Meat -- Quality
- Language: English
- Type: Thesis , Masters , MSc (Animal Science )
- Identifier: http://hdl.handle.net/10353/18732 , vital:42728
- Description: The objective of the study was to determine meat quality, fatty acid (FA) composition and shelf-life stability of longissimus muscle of Nguni heifers fed incremental levels of Opuntia ficus-indica (cactus) cladodes. A total of 32 heifers aged 36 months were allocated randomly to four dietary treatments: 10% cactus, 20% cactus, commercial and control diets for 90 days. The longissimus thoracis et lumborum (LTL) samples were taken from each carcass for the determination of meat quality, retail shelf-life stability and FA composition. Diet had no effect (P > 0.05) on pH and drip display, however, there was an increase in drip display with ageing time (P ≤ 0.05). Meat colour attributes (L* a* b* and C*) were influenced by diet, with 20% cactus diet having lower L* values compared to other diets (P ≤ 0.05). During a 14-day retail display, a diet day interaction was observed for hue angle with the cactus diets having the lowest values at day 14 of display compared to the other diets (P ≤ 0.05). Differences in meat from heifers fed different diets were observed with 20% cactus accounting for significantly (P ≤ 0.05) higher levels of deoxymyoglobin and the lowest levels of oxymyoglobin. Thawing loss and Warner Bratzler shear force decreased (P ≤ 0.05) with ageing period. Meat from heifers fed cactus diets had lower (P ≤ 0.05) proportions of oleic acid (C18:1n9c) and total MUFA, higher (P ≤ 0.05) proportions of total SFA, C15:1, C17:1, linoleic acid (C18:2n6c) and total PUFA. The control diet produced meat with the highest thiobarbituric acid reactive substances (TBARS) values compared to other diets (P ≤ 0.05) and with ageing TBARS values increased (P ≤ 0.05). Diet showed an effect (P ≤ 0.05) on sensory attributes such as overall tenderness and mouth feel with cactus diets accounting for lower scores. However, juiciness, overall tenderness, grassy and animal like attributes increased with ageing (P ≤ 0.05). Inclusion of cactus in the diet did not produce any adverse effects on meat quality, fatty acid composition, lipid oxidation and sensory quality. Therefore, it can be concluded that inclusion of cactus in Nguni heifer finisher diets up to 20% can improve meat quality.
- Full Text:
- Date Issued: 2020
- Authors: Mkhosi, Silungile
- Date: 2020
- Subjects: Meat -- Quality
- Language: English
- Type: Thesis , Masters , MSc (Animal Science )
- Identifier: http://hdl.handle.net/10353/18732 , vital:42728
- Description: The objective of the study was to determine meat quality, fatty acid (FA) composition and shelf-life stability of longissimus muscle of Nguni heifers fed incremental levels of Opuntia ficus-indica (cactus) cladodes. A total of 32 heifers aged 36 months were allocated randomly to four dietary treatments: 10% cactus, 20% cactus, commercial and control diets for 90 days. The longissimus thoracis et lumborum (LTL) samples were taken from each carcass for the determination of meat quality, retail shelf-life stability and FA composition. Diet had no effect (P > 0.05) on pH and drip display, however, there was an increase in drip display with ageing time (P ≤ 0.05). Meat colour attributes (L* a* b* and C*) were influenced by diet, with 20% cactus diet having lower L* values compared to other diets (P ≤ 0.05). During a 14-day retail display, a diet day interaction was observed for hue angle with the cactus diets having the lowest values at day 14 of display compared to the other diets (P ≤ 0.05). Differences in meat from heifers fed different diets were observed with 20% cactus accounting for significantly (P ≤ 0.05) higher levels of deoxymyoglobin and the lowest levels of oxymyoglobin. Thawing loss and Warner Bratzler shear force decreased (P ≤ 0.05) with ageing period. Meat from heifers fed cactus diets had lower (P ≤ 0.05) proportions of oleic acid (C18:1n9c) and total MUFA, higher (P ≤ 0.05) proportions of total SFA, C15:1, C17:1, linoleic acid (C18:2n6c) and total PUFA. The control diet produced meat with the highest thiobarbituric acid reactive substances (TBARS) values compared to other diets (P ≤ 0.05) and with ageing TBARS values increased (P ≤ 0.05). Diet showed an effect (P ≤ 0.05) on sensory attributes such as overall tenderness and mouth feel with cactus diets accounting for lower scores. However, juiciness, overall tenderness, grassy and animal like attributes increased with ageing (P ≤ 0.05). Inclusion of cactus in the diet did not produce any adverse effects on meat quality, fatty acid composition, lipid oxidation and sensory quality. Therefore, it can be concluded that inclusion of cactus in Nguni heifer finisher diets up to 20% can improve meat quality.
- Full Text:
- Date Issued: 2020
Synthesis and characterization of MXS (M = Mo & V) and carbon supported MXS nanocomposites as Pt-free counter electrodes for electrode for DSSC application
- Authors: Bede, Asanda
- Date: 2020
- Subjects: Voltammetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/18599 , vital:42612
- Description: It has been reported that the morphology, crystalline phase composition and electrochemical properties of counter electrode materials such MxS (Mo, V) and carbon supported MxS (Mo, V) composite nanomaterials was of considerable importance because it governs the efficiency of many photon assisted chemical and physical reactions in dye sensitized solar cells (DSSCs). The efficiency of DSSCs with composite counter electrode materials is reliant on the stability of the photochemistry reactions which can be optimized by appropriate doping levels of the composite materials. Moreover, the microstructure such as surface area, distribution of the MxS (Mo, V) and carbon supported MxS (Mo, V) composite nanomaterials, and the stability of the electrostatic bonds between the MxS (Mo, V) with the carbon support also play a significant role in the performance of the DSSCs. This work evaluates the effect of different mole ratios of the MxS (Mo, V) and carbon supported MxS (Mo, V) composite nanomaterials on the morphological, structural and electrochemical properties of the composite materials. MoS2 nanoflakes nanostructures have been synthesized by hydrothermal technique using sodium orthovanadate (Na2MoO4) as precursor. In this work Carbon supported MoS2 NFs have been prepared by physically/chemically mixing different mole ratios of MoS2 NFs with multi-walled carbon nanotubes (MWCNTs) and polyvinylidene in N-methyl-2-pyrrolidinone. The morphological, structural and electrochemical properties of the composite counter electrode materials have been investigated using SEM, XRD FTIR, TEM, RS and CV. SEM analysis has revealed the presence of large MoS2 nanoflakes (NFs) as synthesized. SEM analysis has also revealed significant change in the surface morphology of carbon supported MoS2 composite nanostructures with the change in the mole ratio of the MoS2 NFs and carbon support multi-walled carbon nanotubes. Structural analysis through HRTEM analysis revealed a d-spacing of 0.65 nm with a corresponding (002) lattice plane belonging to a trigonal crystalline phase of MoS2. Also, HRTEM analysis has revealed d-spacing of 0.291 nm corresponding to 002 plane of MWCNTs. Raman spectroscopy has revealed Characteristic Raman vibration frequencies and symmetries at 264.6 cm-1(Eg), 354.2 cm-1 (Ag ) belonging trigonal phase of MoS2 (1T-MoS2). FTIR analysis has revealed a narrow peak at 457.6 cm-1 due Mo-S vibration bond. This observation confirms the success of synthesis of MoS2 nanostructures. Cyclic voltammetry (CV), charge-discharge (CD) and electrochemical impedance spectroscopy (EIS) measurements have revealed that the ratio 6:3:1 have shown to be optimum ratio due to its large reduction rate compared to pristine MoS2 NFs and other carbon supported MoS2 NFs. Calculated Rreduction for the carbon supported MoS2 NFs is the order 3:6:1>1:8:1>6:3:1>8:1:1 indicating the trend of ratio 3:6:1 appeared to have higher reduction rate than the rest of the material and it had far less ΔEpp than the rest of other ratios. All CV curves for both pristine MoS2 NFs and carbon supported MoS2 NFs confirmed a distinct Faradic characteristic. The VS2 nanosheets (NSs) and carbon supported VS2 NSs were also effectively synthesized via hydrothermal method. The SEM micrographs for VS2 NSs and carbon supported VS2 NSs samples reveals level increased. Furthermore, SEM-EDX analysis have confirmed the presence of V and S as well as C and O on carbon supported VS2 nanocomposites, and it clearly shown a gradually blending as the ratios increases. The structural studies through XRD analysis have revealed peaks at 2θ angles of 15.4◦, 28.2◦, 34.2◦, 36.2◦, 43.3◦,48.3◦, 54.4◦, 57.7◦ and 66.2◦ which correspond to the lattice planes (001), (002), (100), (011), (102), (003), (110), (103) and (201) belonging to hexagonal VS2 (H-VS2) crystalline phase as per JCPDS card 36-1139. The HRTEM have revealed that the VS2 NSs have an edge to edge length of ~ 0.294 – 1.248 µm. Also, HRTEM micrographs of VS2 NSs have revealed interplanar d spacing of 0.571 nm belonging to the (001) lattice plane of hexagonal VS2 (H-VS2) structure. FTIR analysis have shown a peak at 558 cm-1 attributed to V-S which is evident that sulfur has bonded with the metal (V) and is in agreement with EDS. CV, CD and EIS measurements have shown that the ratio 1:8:1 is more superior to VS2 NSs and other carbon supported VS2 NSs. Based on Rreduction for the carbon supported nanosheets VS2 nanosheets are ordered as 1:8:1>3:6:1>6:3:1>8:1:1. Carbon supported VS2 NSs of the mole ratio 1:8:1 showed a small resistance of 0.32 Ω. This is further evidence that the carbon supported VS2 NSs of the mole ratio 1:8:1 in addition to revealing excellent catalytic behaviour is also more chemically stable and has good conductivity properties._________
- Full Text:
- Date Issued: 2020
- Authors: Bede, Asanda
- Date: 2020
- Subjects: Voltammetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/18599 , vital:42612
- Description: It has been reported that the morphology, crystalline phase composition and electrochemical properties of counter electrode materials such MxS (Mo, V) and carbon supported MxS (Mo, V) composite nanomaterials was of considerable importance because it governs the efficiency of many photon assisted chemical and physical reactions in dye sensitized solar cells (DSSCs). The efficiency of DSSCs with composite counter electrode materials is reliant on the stability of the photochemistry reactions which can be optimized by appropriate doping levels of the composite materials. Moreover, the microstructure such as surface area, distribution of the MxS (Mo, V) and carbon supported MxS (Mo, V) composite nanomaterials, and the stability of the electrostatic bonds between the MxS (Mo, V) with the carbon support also play a significant role in the performance of the DSSCs. This work evaluates the effect of different mole ratios of the MxS (Mo, V) and carbon supported MxS (Mo, V) composite nanomaterials on the morphological, structural and electrochemical properties of the composite materials. MoS2 nanoflakes nanostructures have been synthesized by hydrothermal technique using sodium orthovanadate (Na2MoO4) as precursor. In this work Carbon supported MoS2 NFs have been prepared by physically/chemically mixing different mole ratios of MoS2 NFs with multi-walled carbon nanotubes (MWCNTs) and polyvinylidene in N-methyl-2-pyrrolidinone. The morphological, structural and electrochemical properties of the composite counter electrode materials have been investigated using SEM, XRD FTIR, TEM, RS and CV. SEM analysis has revealed the presence of large MoS2 nanoflakes (NFs) as synthesized. SEM analysis has also revealed significant change in the surface morphology of carbon supported MoS2 composite nanostructures with the change in the mole ratio of the MoS2 NFs and carbon support multi-walled carbon nanotubes. Structural analysis through HRTEM analysis revealed a d-spacing of 0.65 nm with a corresponding (002) lattice plane belonging to a trigonal crystalline phase of MoS2. Also, HRTEM analysis has revealed d-spacing of 0.291 nm corresponding to 002 plane of MWCNTs. Raman spectroscopy has revealed Characteristic Raman vibration frequencies and symmetries at 264.6 cm-1(Eg), 354.2 cm-1 (Ag ) belonging trigonal phase of MoS2 (1T-MoS2). FTIR analysis has revealed a narrow peak at 457.6 cm-1 due Mo-S vibration bond. This observation confirms the success of synthesis of MoS2 nanostructures. Cyclic voltammetry (CV), charge-discharge (CD) and electrochemical impedance spectroscopy (EIS) measurements have revealed that the ratio 6:3:1 have shown to be optimum ratio due to its large reduction rate compared to pristine MoS2 NFs and other carbon supported MoS2 NFs. Calculated Rreduction for the carbon supported MoS2 NFs is the order 3:6:1>1:8:1>6:3:1>8:1:1 indicating the trend of ratio 3:6:1 appeared to have higher reduction rate than the rest of the material and it had far less ΔEpp than the rest of other ratios. All CV curves for both pristine MoS2 NFs and carbon supported MoS2 NFs confirmed a distinct Faradic characteristic. The VS2 nanosheets (NSs) and carbon supported VS2 NSs were also effectively synthesized via hydrothermal method. The SEM micrographs for VS2 NSs and carbon supported VS2 NSs samples reveals level increased. Furthermore, SEM-EDX analysis have confirmed the presence of V and S as well as C and O on carbon supported VS2 nanocomposites, and it clearly shown a gradually blending as the ratios increases. The structural studies through XRD analysis have revealed peaks at 2θ angles of 15.4◦, 28.2◦, 34.2◦, 36.2◦, 43.3◦,48.3◦, 54.4◦, 57.7◦ and 66.2◦ which correspond to the lattice planes (001), (002), (100), (011), (102), (003), (110), (103) and (201) belonging to hexagonal VS2 (H-VS2) crystalline phase as per JCPDS card 36-1139. The HRTEM have revealed that the VS2 NSs have an edge to edge length of ~ 0.294 – 1.248 µm. Also, HRTEM micrographs of VS2 NSs have revealed interplanar d spacing of 0.571 nm belonging to the (001) lattice plane of hexagonal VS2 (H-VS2) structure. FTIR analysis have shown a peak at 558 cm-1 attributed to V-S which is evident that sulfur has bonded with the metal (V) and is in agreement with EDS. CV, CD and EIS measurements have shown that the ratio 1:8:1 is more superior to VS2 NSs and other carbon supported VS2 NSs. Based on Rreduction for the carbon supported nanosheets VS2 nanosheets are ordered as 1:8:1>3:6:1>6:3:1>8:1:1. Carbon supported VS2 NSs of the mole ratio 1:8:1 showed a small resistance of 0.32 Ω. This is further evidence that the carbon supported VS2 NSs of the mole ratio 1:8:1 in addition to revealing excellent catalytic behaviour is also more chemically stable and has good conductivity properties._________
- Full Text:
- Date Issued: 2020
The role of custodial grandparents in psychosocial well-being of adolescents from single parents in Buffalo City Municipality of Eastern Cape, South Africa
- Authors: Adenike,Folorunsho Fausat
- Date: 2020
- Subjects: Grandparents as parents Grandparent and child Grandparenting
- Language: English
- Type: Thesis , Doctoral , PhD(Social Work)
- Identifier: http://hdl.handle.net/10353/17943 , vital:41994
- Description: It has been a historical norm in African societies for children to leave in the homes of caregivers. Among these caregivers are the grandparents, who are from time immemorial, being a pillar of support to their children in caring for their grandchildren. Against this background, the study assesses custodial the role of grandparents in the psychosocial well-being of adolescent children from single parents' homes in Buffalo City Metropolitan Municipality, Eastern Cape Province, South Africa. The study was guided theoretically by Role and Ryff's psychosocial well-being theories. Four sets of participants totaling 323 gathered using a mixed-method approach comprised of 150 adolescents and 136 custodial grandparents through questionnaires, 30 single parents, through in-depth interviews, and seven social workers through focus group discussions. The study utilized a multi-stage sampling technique to select adolescents and their grandparents, a purposive sampling technique for single parents, and a convenient sampling technique for social workers. The quantitative data were analyzed using descriptive statistics and Pearson's Correlation Coefficient, while the qualitative data were categorized manually into themes and subthemes. Findings indicated a correlation between the attainment of the adolescent children's psychosocial well-being and the effectiveness of the custodial grandparents' role. More also, the challenges encountered by custodial grandparents do affect the attainment of the psychosocial well-being of adolescent children. Furthermore, finding from the study revealed that non-governmental organizations in the municipality were not rendering social support for the custodial grandparents. Finally, the child-support grant received by poor grandparents is grossly inadequate to meet up with the astronomical needs of the adolescent children. The study concluded that custodial grandparents' social support is an effective mechanism in meeting adolescent children's psychosocial well-being. Several recommendations were made from the conclusions to various stakeholders and proposed a responsive conceptual grand-parenting model to cater for effective parenting.
- Full Text:
- Date Issued: 2020
- Authors: Adenike,Folorunsho Fausat
- Date: 2020
- Subjects: Grandparents as parents Grandparent and child Grandparenting
- Language: English
- Type: Thesis , Doctoral , PhD(Social Work)
- Identifier: http://hdl.handle.net/10353/17943 , vital:41994
- Description: It has been a historical norm in African societies for children to leave in the homes of caregivers. Among these caregivers are the grandparents, who are from time immemorial, being a pillar of support to their children in caring for their grandchildren. Against this background, the study assesses custodial the role of grandparents in the psychosocial well-being of adolescent children from single parents' homes in Buffalo City Metropolitan Municipality, Eastern Cape Province, South Africa. The study was guided theoretically by Role and Ryff's psychosocial well-being theories. Four sets of participants totaling 323 gathered using a mixed-method approach comprised of 150 adolescents and 136 custodial grandparents through questionnaires, 30 single parents, through in-depth interviews, and seven social workers through focus group discussions. The study utilized a multi-stage sampling technique to select adolescents and their grandparents, a purposive sampling technique for single parents, and a convenient sampling technique for social workers. The quantitative data were analyzed using descriptive statistics and Pearson's Correlation Coefficient, while the qualitative data were categorized manually into themes and subthemes. Findings indicated a correlation between the attainment of the adolescent children's psychosocial well-being and the effectiveness of the custodial grandparents' role. More also, the challenges encountered by custodial grandparents do affect the attainment of the psychosocial well-being of adolescent children. Furthermore, finding from the study revealed that non-governmental organizations in the municipality were not rendering social support for the custodial grandparents. Finally, the child-support grant received by poor grandparents is grossly inadequate to meet up with the astronomical needs of the adolescent children. The study concluded that custodial grandparents' social support is an effective mechanism in meeting adolescent children's psychosocial well-being. Several recommendations were made from the conclusions to various stakeholders and proposed a responsive conceptual grand-parenting model to cater for effective parenting.
- Full Text:
- Date Issued: 2020
Practices, dynamics and discourses of cross-racial adoption: the case of Buffalo city municipality in South Africa
- Authors: Nyasha, Kausi
- Date: 2020
- Subjects: Interracial adoption -- South Africa -- Eastern Cape Adoption -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD(Social Work)
- Identifier: http://hdl.handle.net/10353/18009 , vital:42003
- Description: This study investigated the practices, dynamics, and discourses pertaining to crossracial adoption (CRA) in the Buffalo City Municipality (BCM) in South Africa. The researcher made use of qualitative methods to collect and analyse relevant data, which was made from both the in-depth interviews and focus group discussions. The research sample comprised of six adoption social workers, ten adoptive parents and ten adoptees, who were selected by means of purposive non-random sampling. The researcher also made use of observations, in order to that relevant, valuable, and rich information could be obtained. All the data was subsequently analysed by means of thematic analysis. The principal findings of the study revealed that although it has been legal since 1991, the practices of CRA in South Africa continues to be controversial and that, in the vast majority of cases, it entails black children being adopted by white parents. Relevant discourses covered cultural genocide, the best interests of adopted children, racial identity, colour-blindness, acculturation, and racial consciousness. The phenomenon of CRA needed to be evaluated from all of these standpoints, owing to the racial, cultural, and political perceptions which continue to linger after generations of enforced racial segregation in South Africa. It is evident from the findings that perceptions pertaining to race, culture, and politics exert a significant influence on social relations in the caring for and protection of vulnerable children and on family dynamics in adoptive families. It also emerged from the findings that CRA placements have begun to decline significantly, owing to factors such as long and tedious assessment processes, the xviii attitudes of social workers, a general lack of adequate pre- and post-adoption support for adoptive parents, and shortages of adoption social work staff and resources. The researcher endeavoured to assess the roles of adoption social workers within the adoption triad with respect to determining the adoptability of children and matching them with prospective adoptive parents, recruiting and selecting prospective adoptive parents, counselling prospective parents, counselling biological parents, counselling adopted children, and the providing of post-adoption services. It could be concluded from the findings that although the practice of CRA is an efficacious and desirable form of care for children who are in need of protection, despite any present shortcomings in relation to legislation pertaining to the practice, the phenomenon requires considerably more attention from relevant academics and researchers than it has received to date. The overarching conclusion which emerged from the findings was that although the practice of CRA has attracted controversy and denunciations from several racial groups, it has unlimited potential for erasing the racial stigmas which continue to haunt South African society as well as affording permanency care to those children who are in need of it. The study ends with some recommendations as well as a conceptual framework to deal with the issues of the practices, dynamics and discourses of CRA in South Africa.
- Full Text:
- Date Issued: 2020
- Authors: Nyasha, Kausi
- Date: 2020
- Subjects: Interracial adoption -- South Africa -- Eastern Cape Adoption -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD(Social Work)
- Identifier: http://hdl.handle.net/10353/18009 , vital:42003
- Description: This study investigated the practices, dynamics, and discourses pertaining to crossracial adoption (CRA) in the Buffalo City Municipality (BCM) in South Africa. The researcher made use of qualitative methods to collect and analyse relevant data, which was made from both the in-depth interviews and focus group discussions. The research sample comprised of six adoption social workers, ten adoptive parents and ten adoptees, who were selected by means of purposive non-random sampling. The researcher also made use of observations, in order to that relevant, valuable, and rich information could be obtained. All the data was subsequently analysed by means of thematic analysis. The principal findings of the study revealed that although it has been legal since 1991, the practices of CRA in South Africa continues to be controversial and that, in the vast majority of cases, it entails black children being adopted by white parents. Relevant discourses covered cultural genocide, the best interests of adopted children, racial identity, colour-blindness, acculturation, and racial consciousness. The phenomenon of CRA needed to be evaluated from all of these standpoints, owing to the racial, cultural, and political perceptions which continue to linger after generations of enforced racial segregation in South Africa. It is evident from the findings that perceptions pertaining to race, culture, and politics exert a significant influence on social relations in the caring for and protection of vulnerable children and on family dynamics in adoptive families. It also emerged from the findings that CRA placements have begun to decline significantly, owing to factors such as long and tedious assessment processes, the xviii attitudes of social workers, a general lack of adequate pre- and post-adoption support for adoptive parents, and shortages of adoption social work staff and resources. The researcher endeavoured to assess the roles of adoption social workers within the adoption triad with respect to determining the adoptability of children and matching them with prospective adoptive parents, recruiting and selecting prospective adoptive parents, counselling prospective parents, counselling biological parents, counselling adopted children, and the providing of post-adoption services. It could be concluded from the findings that although the practice of CRA is an efficacious and desirable form of care for children who are in need of protection, despite any present shortcomings in relation to legislation pertaining to the practice, the phenomenon requires considerably more attention from relevant academics and researchers than it has received to date. The overarching conclusion which emerged from the findings was that although the practice of CRA has attracted controversy and denunciations from several racial groups, it has unlimited potential for erasing the racial stigmas which continue to haunt South African society as well as affording permanency care to those children who are in need of it. The study ends with some recommendations as well as a conceptual framework to deal with the issues of the practices, dynamics and discourses of CRA in South Africa.
- Full Text:
- Date Issued: 2020
Exploring the psychosocial effects of removing teenagers from their homes to places of safety
- Authors: Boxongo , Sisipho
- Date: 2020
- Subjects: Teenagers
- Language: English
- Type: Thesis , Masters , MSW
- Identifier: http://hdl.handle.net/10353/18073 , vital:42226
- Description: The child welfare system investigate over 2 Million children each year for parental abuse or neglect, yet little is known about the psychosocial effects of removing teenagers from their homes and placing them in the place of safety. Although an abusive family would undoubtedly be harmful to children, removing a child from his or her family can be just as traumatic. Long term outcome are rarely observed, and teenagers placed in the place of safety are likely differ from those not placed. Hence this study took a microscopic scrutiny at the effects of the teenager`s removal from their home environment to a place of safety. In carrying out this research qualitative method of data collection was used. The study outlined the factors that lead to removal of teenagers from their home environment to the place of safety. The study found that some of the teenagers who were removed from their home environment were due to poverty, maltreatment, negligence and child abuse at home. The study also revealed that the placement of the teenagers in the places of safety expose the teenagers to psychological, physical, emotional and behavioural negative experiences. The teenagers that participated in the study mentioned that they are stigmatised by the community and peers at school, some also cited that they have lost contact with their families. It was also found out that; the professionals who participated in the study also too experience some challenges in rendering services to the teenagers as sometimes they don`t get informed about the children`s situation on their arrival in the centre. On the other hand, another professional declared that they are trying by all means to cater for all the needs of the children, but they are failed by the case managers and other stakeholders, such as department of social development who delay the process of obtaining court orders which makes it difficult for the child to be funded and also the process of reunifying the child with the biological family.
- Full Text:
- Date Issued: 2020
- Authors: Boxongo , Sisipho
- Date: 2020
- Subjects: Teenagers
- Language: English
- Type: Thesis , Masters , MSW
- Identifier: http://hdl.handle.net/10353/18073 , vital:42226
- Description: The child welfare system investigate over 2 Million children each year for parental abuse or neglect, yet little is known about the psychosocial effects of removing teenagers from their homes and placing them in the place of safety. Although an abusive family would undoubtedly be harmful to children, removing a child from his or her family can be just as traumatic. Long term outcome are rarely observed, and teenagers placed in the place of safety are likely differ from those not placed. Hence this study took a microscopic scrutiny at the effects of the teenager`s removal from their home environment to a place of safety. In carrying out this research qualitative method of data collection was used. The study outlined the factors that lead to removal of teenagers from their home environment to the place of safety. The study found that some of the teenagers who were removed from their home environment were due to poverty, maltreatment, negligence and child abuse at home. The study also revealed that the placement of the teenagers in the places of safety expose the teenagers to psychological, physical, emotional and behavioural negative experiences. The teenagers that participated in the study mentioned that they are stigmatised by the community and peers at school, some also cited that they have lost contact with their families. It was also found out that; the professionals who participated in the study also too experience some challenges in rendering services to the teenagers as sometimes they don`t get informed about the children`s situation on their arrival in the centre. On the other hand, another professional declared that they are trying by all means to cater for all the needs of the children, but they are failed by the case managers and other stakeholders, such as department of social development who delay the process of obtaining court orders which makes it difficult for the child to be funded and also the process of reunifying the child with the biological family.
- Full Text:
- Date Issued: 2020
Developing a Machine Learning Algorithm for Outdoor Scene Image Segmentation
- Authors: Zangwa, Yamkela
- Date: 2020
- Subjects: Computational intelligence Computer science
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/12087 , vital:39150
- Description: Image segmentation is one of the major problems in image processing, computer vision and machine learning fields. The main reason for image segmentation existence is to reduce the gap between computer vision and human vision by training computers with different data. Outdoor image segmentation and classification has become very important in the field of computer vision with its applications in woodland-surveillance, defence and security. The task of assigning an input image to one class from a fixed set of categories seem to be a major problem in image segmentation. The main question that has been addressed in this research is how outdoor image classification algorithms can be improved using Region-based Convolutional Neural Network (R-CNN) architecture. There has been no one segmentation method that works best on any given problem. To determine the best segmentation method for a certain dataset, various tests have to be done in order to achieve the best performance. However deep learning models have often achieved increasing success due to the availability of massive datasets and the expanding model depth and parameterisation. In this research Convolutional Neural Network architecture is used in trying to improve the implementation of outdoor scene image segmentation algorithms, empirical research method was used to answer questions about existing image segmentation algorithms and the techniques used to achieve the best performance. Outdoor scene images were trained on a pre-trained region-based convolutional neural network with Visual Geometric Group-16 (VGG-16) architecture. A pre-trained R-CNN model was retrained on five different sample data, the samples had different sizes. Sample size increased from sample one to five, to increase the size on the last two samples the data was duplicated. 21 test images were used to evaluate all the models. Researchers has shown that deep learning methods perform better in image segmentation because of the increase and availability of datasets. The duplication of images did not yield the best results; however, the model performed well on the first three samples.
- Full Text:
- Date Issued: 2020
- Authors: Zangwa, Yamkela
- Date: 2020
- Subjects: Computational intelligence Computer science
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/12087 , vital:39150
- Description: Image segmentation is one of the major problems in image processing, computer vision and machine learning fields. The main reason for image segmentation existence is to reduce the gap between computer vision and human vision by training computers with different data. Outdoor image segmentation and classification has become very important in the field of computer vision with its applications in woodland-surveillance, defence and security. The task of assigning an input image to one class from a fixed set of categories seem to be a major problem in image segmentation. The main question that has been addressed in this research is how outdoor image classification algorithms can be improved using Region-based Convolutional Neural Network (R-CNN) architecture. There has been no one segmentation method that works best on any given problem. To determine the best segmentation method for a certain dataset, various tests have to be done in order to achieve the best performance. However deep learning models have often achieved increasing success due to the availability of massive datasets and the expanding model depth and parameterisation. In this research Convolutional Neural Network architecture is used in trying to improve the implementation of outdoor scene image segmentation algorithms, empirical research method was used to answer questions about existing image segmentation algorithms and the techniques used to achieve the best performance. Outdoor scene images were trained on a pre-trained region-based convolutional neural network with Visual Geometric Group-16 (VGG-16) architecture. A pre-trained R-CNN model was retrained on five different sample data, the samples had different sizes. Sample size increased from sample one to five, to increase the size on the last two samples the data was duplicated. 21 test images were used to evaluate all the models. Researchers has shown that deep learning methods perform better in image segmentation because of the increase and availability of datasets. The duplication of images did not yield the best results; however, the model performed well on the first three samples.
- Full Text:
- Date Issued: 2020
The effect of feeding varying inclusion levels of velvet bean (Mucuna pruriens) seed meal on growth performance and physicochemical attributes of broiler chicken
- Authors: Mthana, Makiwa Simeon
- Date: 2020
- Subjects: Legumes Broilers (Chickens) Chickens -- Feeding and feeds
- Language: English
- Type: Thesis , Masters/Doctoral , MSc (Animal Science )
- Identifier: http://hdl.handle.net/10353/12032 , vital:39129
- Description: This study was conducted to determine the effect of feeding varying inclusion levels of velvet bean (Mucuna pruriens) seed meal (VBSM) on growth performance and physicochemical attributes of broiler chicken. Mucuna pruriens seed is an indigenous legume seed commonly found in tropical and sub-tropical areas; however, it can also be planted and cultivated. It is a viable source of dietary protein with an average concentration of 33.4%. Soybean is expensive. In addition, the South African production levels do not meet the current demand; hence the majority of soybean oilcake is imported. Recently, consumers have been conscious of the quality of chicken meat from both local and international producers. Therefore, there is a need to explore velvet bean that can grow in poorly fertilised and low rainfall areas. The study was conducted at Fort Cox Agriculture and Forestry Training Institute. One hundred and twelve (112) Cobb broilers were used, with an average weight of 45.2g. Four diets were formulated to be iso-caloric and iso-nitrogenous comprising velvet beans at 0, 10, 15 and 20 % (T1, T2, T3 and T4). The broilers were reared for 42 days with 35 days on experimental diets. Feed intake, body weight gain, feed conversion ratio, mortality, final body weight, carcass weight, and dressing percentage were determined. At day 42, twenty birds per treatment were randomly selected and fasted for five hours with water offered ad libitum. After slaughter the meat pH24, colour (L*, a*, b*), Warner-Bratzler shear force (WBSF), thawing loss (TL), and cooking loss (CL) measurements were performed on 80 breast and 80 thigh muscles. The data for growth performance and physicochemical parameters was analysed using General Linear Model (GLM) procedure of SAS (SAS, 2006), mean separation was done using LSD test option of SAS. Daily feed intake, body weight gain, final weight and carcass weight of broilers from T1 were significantly higher (P < 0.05) from other iii treatments. Daily feed intake (DFI), and body weight gain (BWG) in T1 were also higher (P < 0.05) in both phase 1 and phase 2 compared to other treatments. Feed conversion ratio (FCR) was not influenced by diets (P > 0.05). High (P < 0.05) mortality was observed on broilers fed diet with 0% VBSM compared to those fed diets comprising of VBSM. The diets did not have an effect (P > 0.05) on thigh meat pH24, lightness, redness, and WBSF. Cooking loss (25.69%) was higher (P < 0.05) in thigh meat of broilers fed the control diet. Breasts shear force (14.20) was higher in T4. Cooking loss of breast meat from broilers on T1 and T2 was higher (P < 0.05) than those from other treatments. Breast meat colour (P > 0.05) was not influenced by diets. It can be concluded that the VBSM has an effect on feed intake, growth performance and mortality of broilers, except on FCR and dressing percentage. It was also concluded that the VBSM can be included in broiler diets up to the level of 15% without negatively affecting the quality of meat.
- Full Text:
- Date Issued: 2020
- Authors: Mthana, Makiwa Simeon
- Date: 2020
- Subjects: Legumes Broilers (Chickens) Chickens -- Feeding and feeds
- Language: English
- Type: Thesis , Masters/Doctoral , MSc (Animal Science )
- Identifier: http://hdl.handle.net/10353/12032 , vital:39129
- Description: This study was conducted to determine the effect of feeding varying inclusion levels of velvet bean (Mucuna pruriens) seed meal (VBSM) on growth performance and physicochemical attributes of broiler chicken. Mucuna pruriens seed is an indigenous legume seed commonly found in tropical and sub-tropical areas; however, it can also be planted and cultivated. It is a viable source of dietary protein with an average concentration of 33.4%. Soybean is expensive. In addition, the South African production levels do not meet the current demand; hence the majority of soybean oilcake is imported. Recently, consumers have been conscious of the quality of chicken meat from both local and international producers. Therefore, there is a need to explore velvet bean that can grow in poorly fertilised and low rainfall areas. The study was conducted at Fort Cox Agriculture and Forestry Training Institute. One hundred and twelve (112) Cobb broilers were used, with an average weight of 45.2g. Four diets were formulated to be iso-caloric and iso-nitrogenous comprising velvet beans at 0, 10, 15 and 20 % (T1, T2, T3 and T4). The broilers were reared for 42 days with 35 days on experimental diets. Feed intake, body weight gain, feed conversion ratio, mortality, final body weight, carcass weight, and dressing percentage were determined. At day 42, twenty birds per treatment were randomly selected and fasted for five hours with water offered ad libitum. After slaughter the meat pH24, colour (L*, a*, b*), Warner-Bratzler shear force (WBSF), thawing loss (TL), and cooking loss (CL) measurements were performed on 80 breast and 80 thigh muscles. The data for growth performance and physicochemical parameters was analysed using General Linear Model (GLM) procedure of SAS (SAS, 2006), mean separation was done using LSD test option of SAS. Daily feed intake, body weight gain, final weight and carcass weight of broilers from T1 were significantly higher (P < 0.05) from other iii treatments. Daily feed intake (DFI), and body weight gain (BWG) in T1 were also higher (P < 0.05) in both phase 1 and phase 2 compared to other treatments. Feed conversion ratio (FCR) was not influenced by diets (P > 0.05). High (P < 0.05) mortality was observed on broilers fed diet with 0% VBSM compared to those fed diets comprising of VBSM. The diets did not have an effect (P > 0.05) on thigh meat pH24, lightness, redness, and WBSF. Cooking loss (25.69%) was higher (P < 0.05) in thigh meat of broilers fed the control diet. Breasts shear force (14.20) was higher in T4. Cooking loss of breast meat from broilers on T1 and T2 was higher (P < 0.05) than those from other treatments. Breast meat colour (P > 0.05) was not influenced by diets. It can be concluded that the VBSM has an effect on feed intake, growth performance and mortality of broilers, except on FCR and dressing percentage. It was also concluded that the VBSM can be included in broiler diets up to the level of 15% without negatively affecting the quality of meat.
- Full Text:
- Date Issued: 2020
‘Implementation Strategies Used by Teachers’ Colleges to Prepare Pre-Service Teachers for Science, Technology, Engineering and Mathematics Education in Harare Metropolitan Province in Zimbabwe
- Authors: Chimwe, Ananias
- Date: 2020
- Subjects: Teachers -- In-service training -- Zimbabwe Teachers -- Education (Primary) -- Zimbabwe Science|xStudy and teaching (Primary) -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD (Education)
- Identifier: http://hdl.handle.net/10353/17931 , vital:41981
- Description: The study was carried to establish the strategies used by teacher education colleges to prepare pre-service teachers for STEM Education in Zimbabwe. Invariably, the nature of research questions led the study to be located within the pragmatic paradigm. A mixed method approach and concurrent triangulation design was adopted to examine issues under study. The study adopted stratified random sampling and purposive sampling methods to identify its respondents and participants. Data were collected from respondents who were envisaged knowledgeable about critical issues under study. Several research instruments were used to solicit quantitative and qualitative data. These included: questionnaires, interview schedules, focus group discussions and documents. The sample of the study consisted of 20 lecturers, 50 pre-service teachers, 3 Department of Teacher Education lecturers and 2 Directors in the Ministry of Higher and Tertiary Education Science Innovation, Technology and Development. The study established that 95%of the teacher educators had the requisite STEM content knowledge. Pedagogical content knowledge, knowledge of organisation and education purpose, engineering content and pedagogical content was found lacking. Furthermore, the teacher educators employed 21st century STEM specific inquiry based and constructivist teaching strategies. More so, it was established that government, the Department of Teacher Education and other development partners rendered support to teacher education colleges to prepare for pre-service teachers for STEM education. In addition, the study revealed that preparation of pre-service teachers for STEM was impeded by several structural factors that obtained in teacher education colleges. Overall, the study concluded that teacher educators had requisite STEM knowledge and employed inquiry-based strategies to prepare pre-service teachers for STEM Education. Furthermore, the study recommended that teacher educators’ knowledge in engineering needs further strengthening through workshops and synergies with industry. An alternative model for effective STEM preparation was recommended for consideration.
- Full Text:
- Date Issued: 2020
- Authors: Chimwe, Ananias
- Date: 2020
- Subjects: Teachers -- In-service training -- Zimbabwe Teachers -- Education (Primary) -- Zimbabwe Science|xStudy and teaching (Primary) -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD (Education)
- Identifier: http://hdl.handle.net/10353/17931 , vital:41981
- Description: The study was carried to establish the strategies used by teacher education colleges to prepare pre-service teachers for STEM Education in Zimbabwe. Invariably, the nature of research questions led the study to be located within the pragmatic paradigm. A mixed method approach and concurrent triangulation design was adopted to examine issues under study. The study adopted stratified random sampling and purposive sampling methods to identify its respondents and participants. Data were collected from respondents who were envisaged knowledgeable about critical issues under study. Several research instruments were used to solicit quantitative and qualitative data. These included: questionnaires, interview schedules, focus group discussions and documents. The sample of the study consisted of 20 lecturers, 50 pre-service teachers, 3 Department of Teacher Education lecturers and 2 Directors in the Ministry of Higher and Tertiary Education Science Innovation, Technology and Development. The study established that 95%of the teacher educators had the requisite STEM content knowledge. Pedagogical content knowledge, knowledge of organisation and education purpose, engineering content and pedagogical content was found lacking. Furthermore, the teacher educators employed 21st century STEM specific inquiry based and constructivist teaching strategies. More so, it was established that government, the Department of Teacher Education and other development partners rendered support to teacher education colleges to prepare for pre-service teachers for STEM education. In addition, the study revealed that preparation of pre-service teachers for STEM was impeded by several structural factors that obtained in teacher education colleges. Overall, the study concluded that teacher educators had requisite STEM knowledge and employed inquiry-based strategies to prepare pre-service teachers for STEM Education. Furthermore, the study recommended that teacher educators’ knowledge in engineering needs further strengthening through workshops and synergies with industry. An alternative model for effective STEM preparation was recommended for consideration.
- Full Text:
- Date Issued: 2020
The perceptions of Government Social Protection Programmes in mitigating the challenges faced by street children in Harare Metropolitan Province in Zimbabwe
- Authors: Gunhidzirai, Constance
- Date: 2020
- Subjects: Poverty Alleviation Street children
- Language: English
- Type: Thesis , Doctoral , PhD (Social Work)
- Identifier: http://hdl.handle.net/10353/17998 , vital:42002
- Description: This study was aimed at examining the perceptions of Government Social Protection Programmes in mitigating the challenges faced by street children in Harare Metropolitan Province in Zimbabwe. The study was based on the pragmatism paradigm that triangulated both quantitative and qualitative research methods of collecting data. A questionnaire survey was administered to 202 street children while 32 heads of households were involved in focus group discussions and four Social Workers took part in semi-structured interviews. Drawing from the Human Rights-Based Approach (HRBA), Psychoanalysis Theory and Bronfenbrenner’s Ecological Systems Theory (EST) that guided the study, the findings revealed that street children experienced economic, social, physical and psychological challenges that hindered their attainment of full growth and development. Findings further revealed that street children adopted various coping strategies to mitigate the challenges they encountered in the streets to ensure sustainability. Furthermore, not all Government Social Protection Programmes were effective in addressing the plights of street children. This was due to inadequate funds, corruption and discriminatory criteria for selection of beneficiaries. These impediments hindered the provision of comprehensive social welfare services to street children, which led street children to adopt various coping strategies to mitigate the challenges they encountered in their efforts to ensure sustainability. The study concludes that Government Social Protection Programmes (GSPPs) such as Basic Education Assistance Module, Child Adoption, Institutional Care, National Action Plan for Orphans and Vulnerable Children, Free vii Treatment Order and Harmonized Cash Transfer are not entirely addressing the challenges facing street children in Harare Metropolitan Province. This is because of the criteria used to select street children, which systematically excludes them from benefitting, resulting in extended impoverishment and vulnerability. The study further recommends that the government of Zimbabwe provide productive safety nets and sponsor self-help projects to empower vulnerable households, and source out additional resources such as human resource and finance for Social Protection Programmes from Non-Government Organisations, private companies
- Full Text:
- Date Issued: 2020
- Authors: Gunhidzirai, Constance
- Date: 2020
- Subjects: Poverty Alleviation Street children
- Language: English
- Type: Thesis , Doctoral , PhD (Social Work)
- Identifier: http://hdl.handle.net/10353/17998 , vital:42002
- Description: This study was aimed at examining the perceptions of Government Social Protection Programmes in mitigating the challenges faced by street children in Harare Metropolitan Province in Zimbabwe. The study was based on the pragmatism paradigm that triangulated both quantitative and qualitative research methods of collecting data. A questionnaire survey was administered to 202 street children while 32 heads of households were involved in focus group discussions and four Social Workers took part in semi-structured interviews. Drawing from the Human Rights-Based Approach (HRBA), Psychoanalysis Theory and Bronfenbrenner’s Ecological Systems Theory (EST) that guided the study, the findings revealed that street children experienced economic, social, physical and psychological challenges that hindered their attainment of full growth and development. Findings further revealed that street children adopted various coping strategies to mitigate the challenges they encountered in the streets to ensure sustainability. Furthermore, not all Government Social Protection Programmes were effective in addressing the plights of street children. This was due to inadequate funds, corruption and discriminatory criteria for selection of beneficiaries. These impediments hindered the provision of comprehensive social welfare services to street children, which led street children to adopt various coping strategies to mitigate the challenges they encountered in their efforts to ensure sustainability. The study concludes that Government Social Protection Programmes (GSPPs) such as Basic Education Assistance Module, Child Adoption, Institutional Care, National Action Plan for Orphans and Vulnerable Children, Free vii Treatment Order and Harmonized Cash Transfer are not entirely addressing the challenges facing street children in Harare Metropolitan Province. This is because of the criteria used to select street children, which systematically excludes them from benefitting, resulting in extended impoverishment and vulnerability. The study further recommends that the government of Zimbabwe provide productive safety nets and sponsor self-help projects to empower vulnerable households, and source out additional resources such as human resource and finance for Social Protection Programmes from Non-Government Organisations, private companies
- Full Text:
- Date Issued: 2020
Influence of Tamarix species on soil physicochemical properties and mapping its distribution and density using GIS in Western Cape, South Africa
- Authors: Mlahlwa, Asiphe
- Date: 2020
- Subjects: Tamarisks
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/18588 , vital:42611
- Description: Tamarix ramosissima invasion is unarguably one of the worst ecological disasters in South Africa and is classified under category 1b by the National Environmental Management: Biodiversity Act 2014 (NEM: BA). The exotic Tamarix species was introduced in South Africa during the early 1900s as an ornamental or phytoremediating plant. This study was conducted to assess Tamarix distribution and evaluate its impact on soil physicochemical properties in two sites at Leeu River and Olifant River in Western Cape, South Africa. Samples were collected from Leeu River (which consists both the exotic and native Tamarix species) and Olifant River (only exotic Tamarix species). Three transects were laid from the water point outwards, with exotic Tamarix invading the river bank (first transect), the control on the open land (second transect) and the native Tamarix at the far end of the study site (third transect) in Leeu River. In Olifant, transects were laid according to the degree of invasion, low Tamarix density transect was referred to as T1, the medium as T2 and the high density as T3. Soil samples from each transect were taken from three points, at three soil depths (0-10, 10-20 and 20-30 cm) during winter and summer. Soil physiochemical properties such as soil pH, electro-conductivity (EC), total nitrogen (TN), total carbon (TC), soil organic carbon (SOC), sodium (Na+ ), potassium (K+ ), Calcium (Ca2+), Magnesium (Mg2+), bulk density, soil texture and sodium adsorption ratio (SAR) were determined. Soil chemicals properties including EC, Na+ , SAR, K+ and Mg2+ were found significantly higher under the native and the exotic Tamarix species when compared to Tamarix free soils. In general, salinity of surface soils (0–10 cm) was greater than those in the deeper soils with 5.05 mS/cm and 4.73 mS/cm observed under exotic and native Tamarix species, respectively. High levels of EC, K+ , Ca2+, Na+ , SAR, TN, TC and SOC were observed under T3, followed by T2 with the lowest being recorded in T1 at 0-10 cm. Unlike the soil EC, the effect of Tamarix density on soil pH at 0-10 cm soil profile was not significant. Alterations of soil physicochemical properties were more pronounced under the high Tamarix density as compared to the low invasion. Increased in distance from the river was related to a higher density of the invasive species and also topography had a major role in the change of species density. An increase in Tamarix density, results in high leaf litter which in turn results in salinity and soil nutrient at 0-10 cm. Soil salinity was dramatically increased under Tamarix species. Tamarix species are capable of altering the soil properties making it conducive for their growth.
- Full Text:
- Date Issued: 2020
- Authors: Mlahlwa, Asiphe
- Date: 2020
- Subjects: Tamarisks
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/18588 , vital:42611
- Description: Tamarix ramosissima invasion is unarguably one of the worst ecological disasters in South Africa and is classified under category 1b by the National Environmental Management: Biodiversity Act 2014 (NEM: BA). The exotic Tamarix species was introduced in South Africa during the early 1900s as an ornamental or phytoremediating plant. This study was conducted to assess Tamarix distribution and evaluate its impact on soil physicochemical properties in two sites at Leeu River and Olifant River in Western Cape, South Africa. Samples were collected from Leeu River (which consists both the exotic and native Tamarix species) and Olifant River (only exotic Tamarix species). Three transects were laid from the water point outwards, with exotic Tamarix invading the river bank (first transect), the control on the open land (second transect) and the native Tamarix at the far end of the study site (third transect) in Leeu River. In Olifant, transects were laid according to the degree of invasion, low Tamarix density transect was referred to as T1, the medium as T2 and the high density as T3. Soil samples from each transect were taken from three points, at three soil depths (0-10, 10-20 and 20-30 cm) during winter and summer. Soil physiochemical properties such as soil pH, electro-conductivity (EC), total nitrogen (TN), total carbon (TC), soil organic carbon (SOC), sodium (Na+ ), potassium (K+ ), Calcium (Ca2+), Magnesium (Mg2+), bulk density, soil texture and sodium adsorption ratio (SAR) were determined. Soil chemicals properties including EC, Na+ , SAR, K+ and Mg2+ were found significantly higher under the native and the exotic Tamarix species when compared to Tamarix free soils. In general, salinity of surface soils (0–10 cm) was greater than those in the deeper soils with 5.05 mS/cm and 4.73 mS/cm observed under exotic and native Tamarix species, respectively. High levels of EC, K+ , Ca2+, Na+ , SAR, TN, TC and SOC were observed under T3, followed by T2 with the lowest being recorded in T1 at 0-10 cm. Unlike the soil EC, the effect of Tamarix density on soil pH at 0-10 cm soil profile was not significant. Alterations of soil physicochemical properties were more pronounced under the high Tamarix density as compared to the low invasion. Increased in distance from the river was related to a higher density of the invasive species and also topography had a major role in the change of species density. An increase in Tamarix density, results in high leaf litter which in turn results in salinity and soil nutrient at 0-10 cm. Soil salinity was dramatically increased under Tamarix species. Tamarix species are capable of altering the soil properties making it conducive for their growth.
- Full Text:
- Date Issued: 2020
Towards a reconstruction of Marion Island’s glacial history
- Authors: Rudolph, Elizabeth
- Date: 2020
- Subjects: Glacial landforms Geomorphological mapping
- Language: English
- Type: Thesis , Doctoral , PhD (Geography)
- Identifier: http://hdl.handle.net/10353/18531 , vital:42581
- Description: Southern Hemisphere glacial chronologies can provide valuable insights into interactions between glaciation and past climate changes. The sub-Antarctic Islands provide a valuable terrestrial record of glacial chronologies for the Southern Hemisphere, since they are unique, not only in size and topography, but also in oceanic situation when compared to other continental landmasses (e.g. Antarctica or Patagonia). On sub-Antarctic Marion Island, southern Indian Ocean, the exact timing and extent of the local Last Glacial Maximum is not yet known as glacial reconstructions have mostly been based on palynological proxies and relative-age dating techniques. This study presents 29 cosmogenic 36Cl exposure ages of deglaciated bedrock surfaces and moraine deposits from Marion Island. In addition, a comprehensive glacial-geomorphological map, which in conjunction with exposure ages provide improved temporal and spatial constraints for the island’s glacial history. Results show that the ice reached a local Last Glacial Maximum before 56 ka ago and retreated, with minor stillstands, until ~17 ka. This early deglaciation left island surfaces below 850 m a.s.l. ice-free after ~19 ka, and any subsequent advances during the Late Glacial or Holocene cooling periods would have been restricted to the interior. This glacial chronology is similar to that of some other sub-Antarctic Islands (e.g. the Kerguelen archipelago, Auckland and Campbell islands, and possibly South Georgia) and a number of other Southern Hemisphere glaciers (e.g. in Patagonia and New Zealand) and adds to evidence that suggest the Southern Hemisphere was in a glacial maximum earlier than the global LGM. A combination of climatic drivers such as declining temperatures, a northward migration of oceanic fronts and the Southern Hemisphere Westerly Winds (causing precipitation changes), as well as the physiography of Marion Island, created optimal conditions for glacier growth during Marine Isotope Stage 4 (MIS 4; ~65 ka ago) instead of the global LGM in MIS 2 (~18 ka). These findings redefine the glacial history of Marion Island, and have implications for future investigations on post-glacial landscape development and ecological succession.
- Full Text:
- Date Issued: 2020
- Authors: Rudolph, Elizabeth
- Date: 2020
- Subjects: Glacial landforms Geomorphological mapping
- Language: English
- Type: Thesis , Doctoral , PhD (Geography)
- Identifier: http://hdl.handle.net/10353/18531 , vital:42581
- Description: Southern Hemisphere glacial chronologies can provide valuable insights into interactions between glaciation and past climate changes. The sub-Antarctic Islands provide a valuable terrestrial record of glacial chronologies for the Southern Hemisphere, since they are unique, not only in size and topography, but also in oceanic situation when compared to other continental landmasses (e.g. Antarctica or Patagonia). On sub-Antarctic Marion Island, southern Indian Ocean, the exact timing and extent of the local Last Glacial Maximum is not yet known as glacial reconstructions have mostly been based on palynological proxies and relative-age dating techniques. This study presents 29 cosmogenic 36Cl exposure ages of deglaciated bedrock surfaces and moraine deposits from Marion Island. In addition, a comprehensive glacial-geomorphological map, which in conjunction with exposure ages provide improved temporal and spatial constraints for the island’s glacial history. Results show that the ice reached a local Last Glacial Maximum before 56 ka ago and retreated, with minor stillstands, until ~17 ka. This early deglaciation left island surfaces below 850 m a.s.l. ice-free after ~19 ka, and any subsequent advances during the Late Glacial or Holocene cooling periods would have been restricted to the interior. This glacial chronology is similar to that of some other sub-Antarctic Islands (e.g. the Kerguelen archipelago, Auckland and Campbell islands, and possibly South Georgia) and a number of other Southern Hemisphere glaciers (e.g. in Patagonia and New Zealand) and adds to evidence that suggest the Southern Hemisphere was in a glacial maximum earlier than the global LGM. A combination of climatic drivers such as declining temperatures, a northward migration of oceanic fronts and the Southern Hemisphere Westerly Winds (causing precipitation changes), as well as the physiography of Marion Island, created optimal conditions for glacier growth during Marine Isotope Stage 4 (MIS 4; ~65 ka ago) instead of the global LGM in MIS 2 (~18 ka). These findings redefine the glacial history of Marion Island, and have implications for future investigations on post-glacial landscape development and ecological succession.
- Full Text:
- Date Issued: 2020
Uthelekiso Lwelizwi leMbongi KwisiHobe sikaZolani Mkiva noMzwakhe Mbuli”
- Authors: Makhenyane, Lukhanyo
- Date: 2020
- Subjects: African Languages Language and languages
- Language: English
- Type: Thesis , Masters/Doctoral , Degree
- Identifier: http://hdl.handle.net/10353/18020 , vital:42004
- Description: Despite the vast research on African poetry by scholars like Qangule (1979), Ntuli (1984), Sirayi (1985), Bokoda (1994), Mtumane (2000), Bobelo (2008) and Jadezweni (2013), there is a paucity of extended research on the aesthetic works of African poets in South Africa in the post-apartheid era. In a quest to redress this imbalance, I undertook a comparative study of two prominent African poets in the post-apartheid era in South Africa. This study adds nuance to our understanding of African poetry as it would define African poetry further from an African perspective. Swanepoel (1990) challenges scholars of African literature to have a critical look on the developments of neighbouring literatures as comparing these literatures produces new and useful ideas about African literature. In addition, scholars such as Gerard (1981) and Perera (1991) advocate for the creation and adoption of a comparative methodology for the study of African literature. This led scholars such as Mdaka (2002) to test comparative methodology in assessing ideology and aesthetics in South African isiXhosa novels and Kenyan novels written in English. Likewise, Cutalele (2007) uses comparative methodology in investigating similar themes in the aesthetics works of S.E.K. Mqhayi and Zolani Mkiva. In responding to Swanepoel’s challenge, this study aims to investigate and evaluate the importance of the voice of imbongi in articulating current and burning issues in the post-apartheid South Africa as well as the solutions they propose to some of the problems facing the country. In this study, the methodology swings on the hinges of Ngara’s Marxist theory. The choice of Ngara’s Marxist theory is based largely on its theoretical insights on ideology, form and communication in analysing poetry. Ngara divides ideology into three sub-themes: dominant ideology, which refers to the beliefs, set of values, thoughts and actions of a people in a particular era, authorial ideology that refers to the set of values espoused by the poet and aesthetics ideology, which is the literary convention and stylistic of the poet. Using the comparative method, the voice of imbongi in Mbuli and Mkiva’s poetry is compared over three ideologies – protest, patriotism and revolution. Under the theme of protest, I compare Mkiva and Mbuli’s poetry under two sub-themes, socio-political protest and socio-cultural protest. Mbuli and Mkiva’s protest agitates for change in the political and cultural spheres of the post-apartheid South Africa. Page viii of 290 They comment on issues like leadership and social welfare of South Africans, burning issues of this era. In the theme of patriotism, I examined poetry that displays love and loyalty for one’s country. In displaying their love and loyalty for their country, it is clear that to Mbuli and Mkiva, country refers to Africa, not just South Africa. Furthermore, under the theme of revolution I examined poetry that praises struggle heroes as well as the one that introduces the new struggles of the people of South Africa. In praising revolutionary leaders, Mbuli and Mkiva parade good leadership skills for the new breed of leaders to learn. In discussing the revolutionary theme, they speak of economic freedom as one of the struggles of the new South Africa. In investigating and evaluating their poetry in post-aparthied South Africa, I discovered that in their protest and their revolutionary ideology they express the theme of disillusionment. They speak against corruption in leadership while they question those who violate children and women’s right to life. Such issues were thought to be buried with the death of apartheid. Furthermore, they introduce us to neo-revolution by showing how the struggle for freedom still continues as freedom without economic freedom falls short of freedom.
- Full Text:
- Date Issued: 2020
- Authors: Makhenyane, Lukhanyo
- Date: 2020
- Subjects: African Languages Language and languages
- Language: English
- Type: Thesis , Masters/Doctoral , Degree
- Identifier: http://hdl.handle.net/10353/18020 , vital:42004
- Description: Despite the vast research on African poetry by scholars like Qangule (1979), Ntuli (1984), Sirayi (1985), Bokoda (1994), Mtumane (2000), Bobelo (2008) and Jadezweni (2013), there is a paucity of extended research on the aesthetic works of African poets in South Africa in the post-apartheid era. In a quest to redress this imbalance, I undertook a comparative study of two prominent African poets in the post-apartheid era in South Africa. This study adds nuance to our understanding of African poetry as it would define African poetry further from an African perspective. Swanepoel (1990) challenges scholars of African literature to have a critical look on the developments of neighbouring literatures as comparing these literatures produces new and useful ideas about African literature. In addition, scholars such as Gerard (1981) and Perera (1991) advocate for the creation and adoption of a comparative methodology for the study of African literature. This led scholars such as Mdaka (2002) to test comparative methodology in assessing ideology and aesthetics in South African isiXhosa novels and Kenyan novels written in English. Likewise, Cutalele (2007) uses comparative methodology in investigating similar themes in the aesthetics works of S.E.K. Mqhayi and Zolani Mkiva. In responding to Swanepoel’s challenge, this study aims to investigate and evaluate the importance of the voice of imbongi in articulating current and burning issues in the post-apartheid South Africa as well as the solutions they propose to some of the problems facing the country. In this study, the methodology swings on the hinges of Ngara’s Marxist theory. The choice of Ngara’s Marxist theory is based largely on its theoretical insights on ideology, form and communication in analysing poetry. Ngara divides ideology into three sub-themes: dominant ideology, which refers to the beliefs, set of values, thoughts and actions of a people in a particular era, authorial ideology that refers to the set of values espoused by the poet and aesthetics ideology, which is the literary convention and stylistic of the poet. Using the comparative method, the voice of imbongi in Mbuli and Mkiva’s poetry is compared over three ideologies – protest, patriotism and revolution. Under the theme of protest, I compare Mkiva and Mbuli’s poetry under two sub-themes, socio-political protest and socio-cultural protest. Mbuli and Mkiva’s protest agitates for change in the political and cultural spheres of the post-apartheid South Africa. Page viii of 290 They comment on issues like leadership and social welfare of South Africans, burning issues of this era. In the theme of patriotism, I examined poetry that displays love and loyalty for one’s country. In displaying their love and loyalty for their country, it is clear that to Mbuli and Mkiva, country refers to Africa, not just South Africa. Furthermore, under the theme of revolution I examined poetry that praises struggle heroes as well as the one that introduces the new struggles of the people of South Africa. In praising revolutionary leaders, Mbuli and Mkiva parade good leadership skills for the new breed of leaders to learn. In discussing the revolutionary theme, they speak of economic freedom as one of the struggles of the new South Africa. In investigating and evaluating their poetry in post-aparthied South Africa, I discovered that in their protest and their revolutionary ideology they express the theme of disillusionment. They speak against corruption in leadership while they question those who violate children and women’s right to life. Such issues were thought to be buried with the death of apartheid. Furthermore, they introduce us to neo-revolution by showing how the struggle for freedom still continues as freedom without economic freedom falls short of freedom.
- Full Text:
- Date Issued: 2020
Smallholder farmers’ adaptation strategies to mitigate the effect of drought on maize production in O.R Tambo District Municipality
- Authors: Masinda, Nasiphi
- Date: 2020
- Subjects: Farms, Small
- Language: English
- Type: Thesis , Masters , MSc (Agricultural Economics)
- Identifier: http://hdl.handle.net/10353/18709 , vital:42726
- Description: Drought is a normal periodical event that influences the livelihoods of millions of people around the world and it is considered one of the most devastating natural disasters in economic, social and environmental terms. South Africa is considered a semi-arid country vulnerable to water stress, particularly drought. Drought is expected to affect maize production in South Africa in the coming years. Although drought cannot be controlled, producers can adopt adaptation practices to reduce yield loss caused by drought. Maize is a staple crop in South Africa, which makes it the most important grain crop, being both the major feed grain and the staple food of the majority of the South African population. Literature has identified and presented several adaptation strategies that farmers can use however, it has not been conclusively investigated whether vulnerable smallholder farmers affected by drought are able to use or benefit from them. The study examined drought adaptation strategies employed by smallholder farmers and factors affecting adoption and intensity of adoption of drought mitigation strategies. This study determined smallholder farmer’s adoption of adaptation strategies to mitigate the effects of drought on maize production in O.R Tambo district municipality. The study was carried in ORTDM in the Eastern Cape Province of South Africa. A mixed methods approach utilizing qualitative and quantitative data was employed. Both primary and secondary data sources were used for this study. The study gathered data from ORTDM in the Eastern Cape from 200 smallholder maize producers. Primary data was collected through a structured questionnaire and was complemented by secondary data on maize production, yield and area planted sourced from the Department of Agriculture Forestry and Fisheries. The data collected were analysed using descriptive statistics, the adaptation strategy index in the Statistical Package for Social Sciences (SPSS) software and double hurdle model used Statistical package called STATA (version 12. Results from descriptive analysis identified separate livelihood adoptions which were, increase fertilizer, use savings, indigenous knowledge, sell livestock, off-farm income (salary) and reduction of production. The adaptation strategies adopted by maize farmers are mostly shifting planting date, reduction of maize cultivated area and intercropping. The double hurdle model was used to estimate the factors affecting the farmers’ adoption of drought mitigation strategies and factors which were found to be statistically significant were gender of the household head, level of education of the household head, household size, extension services and land ownership. The Adaptation Strategy Index was used in order to establish the relationship between adopting adaptation strategies and maize production. The farmers ranked the adaptation strategies in terms of their useful in adapting with drought and successfully alleviating decline in maize production. Shifting of planting date, reduction of maize cultivated area, planting drought resistant varieties, crop diversification and intercropping were ranked as the most useful respectively. The findings of this study have a number of policy implications since a number of farmers did nothing to adapt to the effects of drought hence supporting smallholder farmers through training on climate change adaption and adapting options is necessary. Training targeting female headed and poor farmers can have significant positive impacts for increasing the implementation of drought adaptation strategies.
- Full Text:
- Date Issued: 2020
- Authors: Masinda, Nasiphi
- Date: 2020
- Subjects: Farms, Small
- Language: English
- Type: Thesis , Masters , MSc (Agricultural Economics)
- Identifier: http://hdl.handle.net/10353/18709 , vital:42726
- Description: Drought is a normal periodical event that influences the livelihoods of millions of people around the world and it is considered one of the most devastating natural disasters in economic, social and environmental terms. South Africa is considered a semi-arid country vulnerable to water stress, particularly drought. Drought is expected to affect maize production in South Africa in the coming years. Although drought cannot be controlled, producers can adopt adaptation practices to reduce yield loss caused by drought. Maize is a staple crop in South Africa, which makes it the most important grain crop, being both the major feed grain and the staple food of the majority of the South African population. Literature has identified and presented several adaptation strategies that farmers can use however, it has not been conclusively investigated whether vulnerable smallholder farmers affected by drought are able to use or benefit from them. The study examined drought adaptation strategies employed by smallholder farmers and factors affecting adoption and intensity of adoption of drought mitigation strategies. This study determined smallholder farmer’s adoption of adaptation strategies to mitigate the effects of drought on maize production in O.R Tambo district municipality. The study was carried in ORTDM in the Eastern Cape Province of South Africa. A mixed methods approach utilizing qualitative and quantitative data was employed. Both primary and secondary data sources were used for this study. The study gathered data from ORTDM in the Eastern Cape from 200 smallholder maize producers. Primary data was collected through a structured questionnaire and was complemented by secondary data on maize production, yield and area planted sourced from the Department of Agriculture Forestry and Fisheries. The data collected were analysed using descriptive statistics, the adaptation strategy index in the Statistical Package for Social Sciences (SPSS) software and double hurdle model used Statistical package called STATA (version 12. Results from descriptive analysis identified separate livelihood adoptions which were, increase fertilizer, use savings, indigenous knowledge, sell livestock, off-farm income (salary) and reduction of production. The adaptation strategies adopted by maize farmers are mostly shifting planting date, reduction of maize cultivated area and intercropping. The double hurdle model was used to estimate the factors affecting the farmers’ adoption of drought mitigation strategies and factors which were found to be statistically significant were gender of the household head, level of education of the household head, household size, extension services and land ownership. The Adaptation Strategy Index was used in order to establish the relationship between adopting adaptation strategies and maize production. The farmers ranked the adaptation strategies in terms of their useful in adapting with drought and successfully alleviating decline in maize production. Shifting of planting date, reduction of maize cultivated area, planting drought resistant varieties, crop diversification and intercropping were ranked as the most useful respectively. The findings of this study have a number of policy implications since a number of farmers did nothing to adapt to the effects of drought hence supporting smallholder farmers through training on climate change adaption and adapting options is necessary. Training targeting female headed and poor farmers can have significant positive impacts for increasing the implementation of drought adaptation strategies.
- Full Text:
- Date Issued: 2020
Youth crime and the rehabilitation of youth caught up in criminal activities: the case of Alice town and surrounding areas
- Authors: Mdoyi, Ziyatandwa
- Date: 2020
- Subjects: Crime -- Sociological aspects Juvenile delinquency
- Language: English
- Type: Thesis , Masters , MSoc (Sociology)
- Identifier: http://hdl.handle.net/10353/18186 , vital:42240
- Description: iv ABSTRACT The nucleus of this study is youth crime and the rehabilitation of the youth caught up in criminal activities. Conducted in Alice in the Eastern Cape, South Africa, this study scrutinized youth crime prevention techniques utilized in Alice and surrounding areas, and it established their efficacy. The study investigated the elements of rehabilitation available for young offenders in this area. With the social control theory, the structural strain theory and the risk-needs-responsivity guiding this study, the findings revealed that loss of control by conventional institutions, strains that individuals experience and inadequate rehabilitation are determinants of youth crime in and around Alice. With lack of resources as well as inconsistent and inadequate application of these programs, efficacy in minimizing and preventing youth crime proves to be low. At some point in the past, communities had effective diversion programs for the youth but these were no longer practiced. Findings revealed that the root causes of youth crime in this area include poor economic background, youth unemployment, broken families, peer pressure and substance abuse among other causes. Prevention programs do not correspond to the actual causes of crime, and, as such, youth crime prevention programs will not achieve efficacy until they address root causes. On the other hand, rehabilitation is of great importance to achieving minimal youth crime rates. The findings revealed that imprisonment is the only source of rehabilitation for young offenders in Alice, and that it yields positive results, albeit for a short period. This is due to neglect of the causes of crime and utilizing general prevention and rehabilitation. The environment into which the young offenders are placed after v socioeconomic status, unemployment, peer pressure and drug abuse. These result in strains that drive young people to committing crime; consequently, engagement in youth crime leads to loss of social control and it becomes an on-going cycle. The risk-needs-responsivity model emphasizes constructing rehabilitative treatment based on the risk the individual poses to society, including the likelihood to reoffend, the offender‟s needs that might lead the individual to deviant ways of achieving them, and the environment into which the individual is exposed. The study adopted a mixed-methods approach. To obtain qualitative data, the researcher made use of 5 focus group discussions each comprising at least 6 members of the community, in-depth interviews with 15 young offenders who had experience with the justice system, and an in-depth interview with the chief community policing officer of the Alice town police department. For the attainment of quantitative data, questionnaires were administered to 100 community members with 61 usable questionnaires upon retrieval. Qualitative data was analysed using the thematic analysis technique while the quantitative data was analysed using the Statistical Package for Social Science (SPSS) software. In view of the theoretical framework, weak social bonds and ties to family, school and society at large play a role in the engagement of youth in criminal activities. This spawns a loss of control to some extent and, due to this, individuals will experience strain as they have abandoned genuine ways of attaining needs and achieving goals, in this case adopting new illegitimate ways of meeting their needs. This calls for rehabilitation that is tailored specifically for the offender: treatment that addresses the risk the offender poses to society; needs of the offender that may lead to reoffending; the social context and the role it is anticipated to play once the offender gets out of rehabilitation. The key is who to target, what to target and how to target it. vi The study concludes that in order to make crime prevention techniques effective, the first step is addressing the root causes of youth crime given that general techniques have been used and indicate no efficacy due to the neglecting of the social context when arriving at problem solving techniques. These become unbeneficial as they attempt to control crime without getting rid of the causes of crime. Rehabilitation should be directly proportional to offender risk and needs. Specific rehabilitation that is determined by offender risk and needs should be practiced for the achievement of long-term rehabilitation.
- Full Text:
- Date Issued: 2020
- Authors: Mdoyi, Ziyatandwa
- Date: 2020
- Subjects: Crime -- Sociological aspects Juvenile delinquency
- Language: English
- Type: Thesis , Masters , MSoc (Sociology)
- Identifier: http://hdl.handle.net/10353/18186 , vital:42240
- Description: iv ABSTRACT The nucleus of this study is youth crime and the rehabilitation of the youth caught up in criminal activities. Conducted in Alice in the Eastern Cape, South Africa, this study scrutinized youth crime prevention techniques utilized in Alice and surrounding areas, and it established their efficacy. The study investigated the elements of rehabilitation available for young offenders in this area. With the social control theory, the structural strain theory and the risk-needs-responsivity guiding this study, the findings revealed that loss of control by conventional institutions, strains that individuals experience and inadequate rehabilitation are determinants of youth crime in and around Alice. With lack of resources as well as inconsistent and inadequate application of these programs, efficacy in minimizing and preventing youth crime proves to be low. At some point in the past, communities had effective diversion programs for the youth but these were no longer practiced. Findings revealed that the root causes of youth crime in this area include poor economic background, youth unemployment, broken families, peer pressure and substance abuse among other causes. Prevention programs do not correspond to the actual causes of crime, and, as such, youth crime prevention programs will not achieve efficacy until they address root causes. On the other hand, rehabilitation is of great importance to achieving minimal youth crime rates. The findings revealed that imprisonment is the only source of rehabilitation for young offenders in Alice, and that it yields positive results, albeit for a short period. This is due to neglect of the causes of crime and utilizing general prevention and rehabilitation. The environment into which the young offenders are placed after v socioeconomic status, unemployment, peer pressure and drug abuse. These result in strains that drive young people to committing crime; consequently, engagement in youth crime leads to loss of social control and it becomes an on-going cycle. The risk-needs-responsivity model emphasizes constructing rehabilitative treatment based on the risk the individual poses to society, including the likelihood to reoffend, the offender‟s needs that might lead the individual to deviant ways of achieving them, and the environment into which the individual is exposed. The study adopted a mixed-methods approach. To obtain qualitative data, the researcher made use of 5 focus group discussions each comprising at least 6 members of the community, in-depth interviews with 15 young offenders who had experience with the justice system, and an in-depth interview with the chief community policing officer of the Alice town police department. For the attainment of quantitative data, questionnaires were administered to 100 community members with 61 usable questionnaires upon retrieval. Qualitative data was analysed using the thematic analysis technique while the quantitative data was analysed using the Statistical Package for Social Science (SPSS) software. In view of the theoretical framework, weak social bonds and ties to family, school and society at large play a role in the engagement of youth in criminal activities. This spawns a loss of control to some extent and, due to this, individuals will experience strain as they have abandoned genuine ways of attaining needs and achieving goals, in this case adopting new illegitimate ways of meeting their needs. This calls for rehabilitation that is tailored specifically for the offender: treatment that addresses the risk the offender poses to society; needs of the offender that may lead to reoffending; the social context and the role it is anticipated to play once the offender gets out of rehabilitation. The key is who to target, what to target and how to target it. vi The study concludes that in order to make crime prevention techniques effective, the first step is addressing the root causes of youth crime given that general techniques have been used and indicate no efficacy due to the neglecting of the social context when arriving at problem solving techniques. These become unbeneficial as they attempt to control crime without getting rid of the causes of crime. Rehabilitation should be directly proportional to offender risk and needs. Specific rehabilitation that is determined by offender risk and needs should be practiced for the achievement of long-term rehabilitation.
- Full Text:
- Date Issued: 2020
Analysis of maximum power point tracking data for obtaining photovoltaic parameters
- Authors: Chitura, Anesu Godfrey
- Date: 2020
- Subjects: Photovoltaic power system
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/18576 , vital:42610
- Description: As a standard, photovoltaic (PV) modules are rated by the use of standard test conditions (STC). Such details entail current and voltage (I-V) measurements for modules under an irradiance of 1000 W/m2 an air mass ration of 1.5 global spectrum and 25˚C cell temperature. Outdoor weather conditions continuously vary with time and from one location to the other. This further offset the expected operational power outputs as outdoor conditions are generally characterized by high cell temperatures. The technology one uses will also complicate the power output prediction since different module technologies respond to these outdoor conditions differently. I-V tracers are able to measure the full I-V curve of the module thus can give the operational PV parameters at any given time. However, these tracers are sold at exorbitant prices and they require skilled personnel in order to operate them. Most if not all tracers require isolation of the module under test thereby disrupting the power production function of the module._________________________________________________________________________________________________________________________________________ In this study a method to obtain photovoltaic (PV) parameters using the maximum power point tracking (MPPT) data is presented and tested under natural outdoor conditions. The method features a customized data acquisition system (DAS) designed for the measurement and storage of meteorological and MPPT data. The DAS is capable of extracting parameters from any combination of modules with an open circuit voltage 〖(V〗_oc) less than or equal to 120 Volts and a short circuit current 〖(I〗_sc) of 100 Amps. The system used is capable of extracting MPPT data using a reliable, improved storage and a programmable data logger. In order to match the sampling operational speeds of internal charge controller switches a computer interfaced Peripheral Component Interconnect (PCI) card was also used. Data collection and characterization of the MPPT data was done in such a way that the power generation process remained uninterrupted throughout the whole process. The regression nonlinear least squares method was used to fit MPPT crests and obtain the knee part of the I-V curve. This was then extrapolated to obtain the full I-V curve, which then produces the operational PV parameters. The resultant parameters from the characterization process were logged and accessible at any time. The end result was a method that can be incorporated within a charge controller for quick, hands-free PV parameter extraction, using only the MPPT scanned data.
- Full Text:
- Date Issued: 2020
- Authors: Chitura, Anesu Godfrey
- Date: 2020
- Subjects: Photovoltaic power system
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/18576 , vital:42610
- Description: As a standard, photovoltaic (PV) modules are rated by the use of standard test conditions (STC). Such details entail current and voltage (I-V) measurements for modules under an irradiance of 1000 W/m2 an air mass ration of 1.5 global spectrum and 25˚C cell temperature. Outdoor weather conditions continuously vary with time and from one location to the other. This further offset the expected operational power outputs as outdoor conditions are generally characterized by high cell temperatures. The technology one uses will also complicate the power output prediction since different module technologies respond to these outdoor conditions differently. I-V tracers are able to measure the full I-V curve of the module thus can give the operational PV parameters at any given time. However, these tracers are sold at exorbitant prices and they require skilled personnel in order to operate them. Most if not all tracers require isolation of the module under test thereby disrupting the power production function of the module._________________________________________________________________________________________________________________________________________ In this study a method to obtain photovoltaic (PV) parameters using the maximum power point tracking (MPPT) data is presented and tested under natural outdoor conditions. The method features a customized data acquisition system (DAS) designed for the measurement and storage of meteorological and MPPT data. The DAS is capable of extracting parameters from any combination of modules with an open circuit voltage 〖(V〗_oc) less than or equal to 120 Volts and a short circuit current 〖(I〗_sc) of 100 Amps. The system used is capable of extracting MPPT data using a reliable, improved storage and a programmable data logger. In order to match the sampling operational speeds of internal charge controller switches a computer interfaced Peripheral Component Interconnect (PCI) card was also used. Data collection and characterization of the MPPT data was done in such a way that the power generation process remained uninterrupted throughout the whole process. The regression nonlinear least squares method was used to fit MPPT crests and obtain the knee part of the I-V curve. This was then extrapolated to obtain the full I-V curve, which then produces the operational PV parameters. The resultant parameters from the characterization process were logged and accessible at any time. The end result was a method that can be incorporated within a charge controller for quick, hands-free PV parameter extraction, using only the MPPT scanned data.
- Full Text:
- Date Issued: 2020