Use of eco-art education in supporting the establishment of sustainability competencies in basic education: an interventionist case study
- Authors: Da Silva, Juliana Schmidt
- Date: 2020
- Subjects: Environment (Art) , Environmental education -- Brazil , Sustainable development -- Brazil , Education -- Curricula -- Brazil , Eco-art education
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/166127 , vital:41331
- Description: Recent socioecological approaches in Environmental Education acknowledge the complexity of “real-world situations”, which include environmental problems. One response to the challenge of enabling people to develop sustainability is the key competencies in sustainability framework. It can be faced as a guide to planning Environmental Education actions. On the other side, art practices hold potential to expand learning in varied ways. Art can offer the strategies employed in learning processes directed to sustainability, constituting the field of eco-art education. This research aims to investigate the integration of the visions of the key competencies in sustainability and the eco-art education in an Environmental Education project at high school level. Horta and Gastronomia (Vegetable Garden and Gastronomy) is an extra-curricular activity which happens every year at Irmão Jaime Biazus high school in Porto Alegre, Brazil. It addresses food security and sustainability associating the garden, the kitchen and exploration of sustainability issues using eco-art strategies. Action research approach is used, defining two research cycles to explore the effectiveness of eco-art for the development of key competencies in sustainability. The first cycle focuses on the eco-art activities applied in Horta and Gastronomia (2017 group) while the second cycle deals with a post-project intervention designed to observe indicators of the sustainability competencies and further explore eco-art strategies. This study adds to the field of sustainability competencies by exploring teaching strategies through eco-art education. Insight into key competencies in sustainability is given by presenting the investigation of the group of students about a situation of their reality. The activities implemented, classified according to their objectives, are contextualized regarding the competencies and in learning sequences. This research also contributes to the development of the sustainability competencies framework by applying the theory to a basic education level, adapting the work originally proposed to higher education contexts.
- Full Text:
- Date Issued: 2020
- Authors: Da Silva, Juliana Schmidt
- Date: 2020
- Subjects: Environment (Art) , Environmental education -- Brazil , Sustainable development -- Brazil , Education -- Curricula -- Brazil , Eco-art education
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/166127 , vital:41331
- Description: Recent socioecological approaches in Environmental Education acknowledge the complexity of “real-world situations”, which include environmental problems. One response to the challenge of enabling people to develop sustainability is the key competencies in sustainability framework. It can be faced as a guide to planning Environmental Education actions. On the other side, art practices hold potential to expand learning in varied ways. Art can offer the strategies employed in learning processes directed to sustainability, constituting the field of eco-art education. This research aims to investigate the integration of the visions of the key competencies in sustainability and the eco-art education in an Environmental Education project at high school level. Horta and Gastronomia (Vegetable Garden and Gastronomy) is an extra-curricular activity which happens every year at Irmão Jaime Biazus high school in Porto Alegre, Brazil. It addresses food security and sustainability associating the garden, the kitchen and exploration of sustainability issues using eco-art strategies. Action research approach is used, defining two research cycles to explore the effectiveness of eco-art for the development of key competencies in sustainability. The first cycle focuses on the eco-art activities applied in Horta and Gastronomia (2017 group) while the second cycle deals with a post-project intervention designed to observe indicators of the sustainability competencies and further explore eco-art strategies. This study adds to the field of sustainability competencies by exploring teaching strategies through eco-art education. Insight into key competencies in sustainability is given by presenting the investigation of the group of students about a situation of their reality. The activities implemented, classified according to their objectives, are contextualized regarding the competencies and in learning sequences. This research also contributes to the development of the sustainability competencies framework by applying the theory to a basic education level, adapting the work originally proposed to higher education contexts.
- Full Text:
- Date Issued: 2020
A formative intervention study of how learner voice and leadership can be developed within a Learner Representative Council (LRC) in an urban combined school, Namibia
- Authors: Shipopyeni, Salomo S M
- Date: 2020
- Subjects: Education, Secondary -- Namibia , Student government -- Namibia -- Case studies , Student participation in administration -- Namibia -- Case studies
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/144934 , vital:38393
- Description: The Namibian Education system, after the country gained independence, introduced various reforms to ensure the attainment of the educational goals of access, quality, equity and democracy in schools. One of the policies introduced to promote democracy in our schools was The Educational Act 16 of 2001, which gave birth to the establishment of Learners Representatives Councils (LRC) in schools. The LRC body is the legal learner leadership body established to ensure learners are represented in school leadership. However, various studies have revealed that this legal body of learners in many schools has been merely ‘rubber-stamping’ decisions made by teachers; learners have had very little input in decisions that affect them as learners. Thus, I was prompted to conduct this formative intervention study on learner leadership at an urban combined school in Namibia. Informed by distributed and transformative leadership theories, the study aimed to develop leadership within the LRC members and the needed expansive transformation regarding leadership practices in school. The intention was for learners to be enabled to practice their democratic right in decision-making processes in matters that concerned their schooling and learning. This study was theoretically and analytically framed by second generation CulturalHistorical Activity Theory. The participants included 12 LRC members, the LRC liaison teacher, the class register teacher, three school management team members and the principal. The research method was a case study, underpinned by the critical paradigm to bring about the fundamental expansive transformation in learner leadership practices at the case study school. This qualitative study was divided into two phases, a contextual profiling phase and an intervention phase. Data were generated through document analysis, observation, questionnaires, focus group interviews and Change Laboratory Workshops. The data were generated to answer the over-arching question: How learner voice and leadership can be developed within a Learner Representative Council (LRC) in an urban combined school, Namibia. The data were analysed inductively and abductively. The key findings were: first, there were a variety of understandings of the concept learner leadership; second, the involvement of LRC members in decision-making processes was limited to involvement in organising extracurricular activities and controlling of other learners at school; third, leadership development opportunities for learners at the case study school were only provided through training at the beginning of the year and the LRC carrying out various activities and roles at the case study school. Several challenges that constrained the LRC voice and leadership development were surfaced and, through Change Laboratory Workshops, the participants of the activity system together with me (the researcher-interventionist), identified the expansive learning opportunities to develop leadership amongst Learner Representative Council (LRC) members. In the final analysis, this study will contribute to the production of knowledge on the concept of learner leadership in the context of Namibia. Fellow scholars, professionals, colleagues and policy makers in education are requested to engage with this thesis to contribute to our understanding of this important aspect of our field and speak back to policy.
- Full Text:
- Date Issued: 2020
- Authors: Shipopyeni, Salomo S M
- Date: 2020
- Subjects: Education, Secondary -- Namibia , Student government -- Namibia -- Case studies , Student participation in administration -- Namibia -- Case studies
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/144934 , vital:38393
- Description: The Namibian Education system, after the country gained independence, introduced various reforms to ensure the attainment of the educational goals of access, quality, equity and democracy in schools. One of the policies introduced to promote democracy in our schools was The Educational Act 16 of 2001, which gave birth to the establishment of Learners Representatives Councils (LRC) in schools. The LRC body is the legal learner leadership body established to ensure learners are represented in school leadership. However, various studies have revealed that this legal body of learners in many schools has been merely ‘rubber-stamping’ decisions made by teachers; learners have had very little input in decisions that affect them as learners. Thus, I was prompted to conduct this formative intervention study on learner leadership at an urban combined school in Namibia. Informed by distributed and transformative leadership theories, the study aimed to develop leadership within the LRC members and the needed expansive transformation regarding leadership practices in school. The intention was for learners to be enabled to practice their democratic right in decision-making processes in matters that concerned their schooling and learning. This study was theoretically and analytically framed by second generation CulturalHistorical Activity Theory. The participants included 12 LRC members, the LRC liaison teacher, the class register teacher, three school management team members and the principal. The research method was a case study, underpinned by the critical paradigm to bring about the fundamental expansive transformation in learner leadership practices at the case study school. This qualitative study was divided into two phases, a contextual profiling phase and an intervention phase. Data were generated through document analysis, observation, questionnaires, focus group interviews and Change Laboratory Workshops. The data were generated to answer the over-arching question: How learner voice and leadership can be developed within a Learner Representative Council (LRC) in an urban combined school, Namibia. The data were analysed inductively and abductively. The key findings were: first, there were a variety of understandings of the concept learner leadership; second, the involvement of LRC members in decision-making processes was limited to involvement in organising extracurricular activities and controlling of other learners at school; third, leadership development opportunities for learners at the case study school were only provided through training at the beginning of the year and the LRC carrying out various activities and roles at the case study school. Several challenges that constrained the LRC voice and leadership development were surfaced and, through Change Laboratory Workshops, the participants of the activity system together with me (the researcher-interventionist), identified the expansive learning opportunities to develop leadership amongst Learner Representative Council (LRC) members. In the final analysis, this study will contribute to the production of knowledge on the concept of learner leadership in the context of Namibia. Fellow scholars, professionals, colleagues and policy makers in education are requested to engage with this thesis to contribute to our understanding of this important aspect of our field and speak back to policy.
- Full Text:
- Date Issued: 2020
An historical analysis of the development of a company as a single enterprise and the impact on group company taxation
- Authors: Els, Tania
- Date: 2020
- Subjects: Taxation -- South Africa , Taxation -- History , Taxation -- Law and legislation -- South Africa , Business enterprises -- South Africa , Business enterprises -- Taxation -- Law and legislation -- South Africa , Corporation law -- South Africa , South Africa. Income Tax Act, 1962 , South Africa. Companies Act, 2008 , Separate legal personality , Group taxation
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/154241 , vital:39628
- Description: The company is considered a separate legal entity in both legislation and jurisprudence. The “veil” separating the company and its shareholders is a doctrine entrenched in company law that originated centuries ago. The doctrine is based on conditions that existed during a period that commenced with trading forms less complicated than the corporate groups found today. Trading forms known as guilds could be traced back to 1087, which gradually developed into regulated companies and, in the last century, into the joint-stock company form. The modern era has seen the development of groups of companies carrying on business as economic units. Company law, in regulating business forms, has failed to acknowledge the corporate group as a new business entity. The main purpose of this research was to analyse the origins of the separate legal personality of a company and its relevance for the present corporate group structures. The research aimed to understand company law and jurisprudence in South Africa in relation to the legal personality of a company and a corporate group. The final objective of this reform-orientated doctrinal research thesis was to provide clarity on the need to consider granting separate legal identity to corporate groups in recognition of their economic unity. A historically contextualised analysis was carried out on the development of trading through unregulated forms of businesses to the creation of the company as a regulated entity. The development of the legal persona of a company in legislation as well as jurisprudence was critically analysed in on the context of companies within a corporate group. A case study of a South African corporate group was used to highlight the different characteristics of the companies doing business in the form of a corporate group. The thesis concluded by recommending that legal personality should be extended to include a corporate group in order to facilitate the introduction of a group taxation regime.
- Full Text:
- Date Issued: 2020
- Authors: Els, Tania
- Date: 2020
- Subjects: Taxation -- South Africa , Taxation -- History , Taxation -- Law and legislation -- South Africa , Business enterprises -- South Africa , Business enterprises -- Taxation -- Law and legislation -- South Africa , Corporation law -- South Africa , South Africa. Income Tax Act, 1962 , South Africa. Companies Act, 2008 , Separate legal personality , Group taxation
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/154241 , vital:39628
- Description: The company is considered a separate legal entity in both legislation and jurisprudence. The “veil” separating the company and its shareholders is a doctrine entrenched in company law that originated centuries ago. The doctrine is based on conditions that existed during a period that commenced with trading forms less complicated than the corporate groups found today. Trading forms known as guilds could be traced back to 1087, which gradually developed into regulated companies and, in the last century, into the joint-stock company form. The modern era has seen the development of groups of companies carrying on business as economic units. Company law, in regulating business forms, has failed to acknowledge the corporate group as a new business entity. The main purpose of this research was to analyse the origins of the separate legal personality of a company and its relevance for the present corporate group structures. The research aimed to understand company law and jurisprudence in South Africa in relation to the legal personality of a company and a corporate group. The final objective of this reform-orientated doctrinal research thesis was to provide clarity on the need to consider granting separate legal identity to corporate groups in recognition of their economic unity. A historically contextualised analysis was carried out on the development of trading through unregulated forms of businesses to the creation of the company as a regulated entity. The development of the legal persona of a company in legislation as well as jurisprudence was critically analysed in on the context of companies within a corporate group. A case study of a South African corporate group was used to highlight the different characteristics of the companies doing business in the form of a corporate group. The thesis concluded by recommending that legal personality should be extended to include a corporate group in order to facilitate the introduction of a group taxation regime.
- Full Text:
- Date Issued: 2020
Perceptions of health care professionals at the Nelson Mandela University of the Auntie Stella sexual and reproductive health education toolkit
- Authors: Ndlangalavu, Siyasanga
- Date: 2020
- Subjects: Sexual health
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/46419 , vital:39589
- Description: Sexual and reproductive health education in South Africa appears to be failing young people as evidenced by the numbers of unplanned pregnancies and sexually transmitted diseases resulting from poor sexual health decision making. High-risk behaviours amongst youth are likely to be a product of the interplay of multiple risk factors on individual and interpersonal levels. The Auntie Stella: Teenagers Talk about Sex, Life and Relationships, is a sexual and reproductive health education toolkit with developmentally timed interventions for sexual and reproductive health education for adolescents. This tool kit has been successfully utilized in such countries as Zimbabwe, Tanzania, Malawi, Mozambique and Zambia. The study aimed to establish if the University health care professionals, including HIV counsellors and nurses, perceive Auntie Stellato be a useful sexual health and reproduction education programme to generate knowledge and prompt and promote safer sexual behaviour. An exploratory descriptive qualitative research design was be utilized, and purposive sampling was employed. Data was collected via focus groups where the toolkit was administered and discussed. Six focus groups were conducted with 12 participants from the Nelson Mandela University’s Campus Health Clinics. The data obtained was analyzed using Braun and Clarke’s (2006) six-step method of thematic analysis. The findings of this study revealed that the Nelson Mandela University health care professionals perceived the Auntie Stellatoolkit as being useful and applicable to the university context in terms of relatability. They expressed thatthe programme is ideally youth-friendly and appropriate for university students. The findings of this small study may have important implications for future research of implementation of sexual and reproductive health education programmes in Higher Education Institutions.
- Full Text:
- Date Issued: 2020
- Authors: Ndlangalavu, Siyasanga
- Date: 2020
- Subjects: Sexual health
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/46419 , vital:39589
- Description: Sexual and reproductive health education in South Africa appears to be failing young people as evidenced by the numbers of unplanned pregnancies and sexually transmitted diseases resulting from poor sexual health decision making. High-risk behaviours amongst youth are likely to be a product of the interplay of multiple risk factors on individual and interpersonal levels. The Auntie Stella: Teenagers Talk about Sex, Life and Relationships, is a sexual and reproductive health education toolkit with developmentally timed interventions for sexual and reproductive health education for adolescents. This tool kit has been successfully utilized in such countries as Zimbabwe, Tanzania, Malawi, Mozambique and Zambia. The study aimed to establish if the University health care professionals, including HIV counsellors and nurses, perceive Auntie Stellato be a useful sexual health and reproduction education programme to generate knowledge and prompt and promote safer sexual behaviour. An exploratory descriptive qualitative research design was be utilized, and purposive sampling was employed. Data was collected via focus groups where the toolkit was administered and discussed. Six focus groups were conducted with 12 participants from the Nelson Mandela University’s Campus Health Clinics. The data obtained was analyzed using Braun and Clarke’s (2006) six-step method of thematic analysis. The findings of this study revealed that the Nelson Mandela University health care professionals perceived the Auntie Stellatoolkit as being useful and applicable to the university context in terms of relatability. They expressed thatthe programme is ideally youth-friendly and appropriate for university students. The findings of this small study may have important implications for future research of implementation of sexual and reproductive health education programmes in Higher Education Institutions.
- Full Text:
- Date Issued: 2020
The past meets the present: exploring the biogeography of extant plecoptera of South Africa with reference to ancient middle permian fossil forms from the Onder Karoo locality near Sutherland
- Authors: Kirkaldy, Benjamin Puleng
- Date: 2020
- Subjects: Stoneflies, Fossil -- South Africa -- Northern Cape , Palaeopteron -- South Africa -- Northern Cape , Stoneflies -- Evolution , Insects, Fossil -- South Africa -- Northern Cape , Paleoentomology , Paleoentomology -- South Africa -- Northern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/165755 , vital:41278
- Description: The Onder Karoo fossil locality near Sutherland, Northern Cape, recently yielded an unprecedented diversity of middle Permian insects, which were preserved in deposits of an aquatic lake margin system, in the Lowermost Abrahamskraal Formation. A large number of Plecoptera (stonefly) specimens were found, and this study represents an in-depth analysis of these species in the context of plecopteran evolution. A significant contribution to current knowledge of the Plecoptera from the middle Permian to the present has been made, utilizing a combination of fossil and phylogenetic evidence to better understand the origins, evolution, diversity and biogeography of the stoneflies. Three new plecopteran species have been described from the Onder Karoo locality, which is recognized here as the first Lagerstätte of its kind in Gondwana. Possible ecological links and relationships with the plecopterans described here have been suggested, using extant Plecoptera as analogues. An in-depth, fossilcalibrated, dated phylogeny of the Plecoptera was completed, using representatives from all three dominant lineages, the Antarctoperlaria, Systellognatha and the Euholognatha. This provides strong support for the monophyly of the Notonemouridae and the Antarctoperlaria, however the monophyly of Systellognatha and Euholognatha was not supported. The Notonemouridae were found to represent an earlier divergence than previously believed, forming a sister group to the remaining Plecoptera. Through a combination of fossil and molecular evidence, strong support was found for the current distribution of the Plecoptera worldwide being attributable to vicariance caused by the rifting of Pangea, and subsequently Gondwana and Laurasia, and long range dispersal. The focussed effort to include Southern Hemisphere stoneflies throughout this study has been a valuable step in reducing the Northern Hemisphere bias which currently dominates plecopteran research and has assisted in opening the way for future research into this important group on a global scale.
- Full Text:
- Date Issued: 2020
- Authors: Kirkaldy, Benjamin Puleng
- Date: 2020
- Subjects: Stoneflies, Fossil -- South Africa -- Northern Cape , Palaeopteron -- South Africa -- Northern Cape , Stoneflies -- Evolution , Insects, Fossil -- South Africa -- Northern Cape , Paleoentomology , Paleoentomology -- South Africa -- Northern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/165755 , vital:41278
- Description: The Onder Karoo fossil locality near Sutherland, Northern Cape, recently yielded an unprecedented diversity of middle Permian insects, which were preserved in deposits of an aquatic lake margin system, in the Lowermost Abrahamskraal Formation. A large number of Plecoptera (stonefly) specimens were found, and this study represents an in-depth analysis of these species in the context of plecopteran evolution. A significant contribution to current knowledge of the Plecoptera from the middle Permian to the present has been made, utilizing a combination of fossil and phylogenetic evidence to better understand the origins, evolution, diversity and biogeography of the stoneflies. Three new plecopteran species have been described from the Onder Karoo locality, which is recognized here as the first Lagerstätte of its kind in Gondwana. Possible ecological links and relationships with the plecopterans described here have been suggested, using extant Plecoptera as analogues. An in-depth, fossilcalibrated, dated phylogeny of the Plecoptera was completed, using representatives from all three dominant lineages, the Antarctoperlaria, Systellognatha and the Euholognatha. This provides strong support for the monophyly of the Notonemouridae and the Antarctoperlaria, however the monophyly of Systellognatha and Euholognatha was not supported. The Notonemouridae were found to represent an earlier divergence than previously believed, forming a sister group to the remaining Plecoptera. Through a combination of fossil and molecular evidence, strong support was found for the current distribution of the Plecoptera worldwide being attributable to vicariance caused by the rifting of Pangea, and subsequently Gondwana and Laurasia, and long range dispersal. The focussed effort to include Southern Hemisphere stoneflies throughout this study has been a valuable step in reducing the Northern Hemisphere bias which currently dominates plecopteran research and has assisted in opening the way for future research into this important group on a global scale.
- Full Text:
- Date Issued: 2020
The precarious ‘good mother’ position: a psychosocial reading of maternal subjectivity of working mothers in scarcely-resourced South African communities
- Authors: Kinahan-Sweeney, Siobhan
- Date: 2020
- Subjects: Motherhood -- Psychological aspects -- South Africa , Working mothers -- South Africa -- Attitudes , Working mothers -- South Africa -- Psychology
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142464 , vital:38082
- Description: This psychosocial study investigates the maternal subjectivities of mothers returning to work after maternity leave, who are living in scarcely-resourced Cape Town communities in South Africa. Engaging with interview texts and listening to mothers’ talk, I explore how and why maternal subjectivity is constructed discursively and defensively in our talk. This thesis claims that these particular mothers predominately employ instrumental mothering discourse. The traditional subject position of the intensive mother – which is typically assumed to be the ‘good mother’ – is not a position available to these mothers due to their social circumstances and working role. Subsequently, material provision, the baby’s thriving and surviving body, finding substitute carers and maternal preoccupation are constructed as qualities of ‘good mothering’ in their talk. This ‘good mother’ position, however, is a precarious position that both these mothers and I invest in to defend against feelings towards their babies and themselves as well as to deny (maternal) ambivalence in a problematic social system. In a combined analysis drawing on discursive theory and psychoanalysis, more specifically contemporary attachment theory and intersubjectivity theory, I illustrate how both these mothers and I – as emotional, social and political subjects – co-construct maternal subjectivity. Based on the findings, recommendations for parent-infant interventions are discussed. Arguing that a purely psychoanalytic reading of investment perpetuates notions of individual blame and pathology, I advocate for a psychosocial reading that does not neglect failing social systems but rather pursues an open and reflective, yet critical, mindfulness when listening to talk.
- Full Text:
- Date Issued: 2020
- Authors: Kinahan-Sweeney, Siobhan
- Date: 2020
- Subjects: Motherhood -- Psychological aspects -- South Africa , Working mothers -- South Africa -- Attitudes , Working mothers -- South Africa -- Psychology
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142464 , vital:38082
- Description: This psychosocial study investigates the maternal subjectivities of mothers returning to work after maternity leave, who are living in scarcely-resourced Cape Town communities in South Africa. Engaging with interview texts and listening to mothers’ talk, I explore how and why maternal subjectivity is constructed discursively and defensively in our talk. This thesis claims that these particular mothers predominately employ instrumental mothering discourse. The traditional subject position of the intensive mother – which is typically assumed to be the ‘good mother’ – is not a position available to these mothers due to their social circumstances and working role. Subsequently, material provision, the baby’s thriving and surviving body, finding substitute carers and maternal preoccupation are constructed as qualities of ‘good mothering’ in their talk. This ‘good mother’ position, however, is a precarious position that both these mothers and I invest in to defend against feelings towards their babies and themselves as well as to deny (maternal) ambivalence in a problematic social system. In a combined analysis drawing on discursive theory and psychoanalysis, more specifically contemporary attachment theory and intersubjectivity theory, I illustrate how both these mothers and I – as emotional, social and political subjects – co-construct maternal subjectivity. Based on the findings, recommendations for parent-infant interventions are discussed. Arguing that a purely psychoanalytic reading of investment perpetuates notions of individual blame and pathology, I advocate for a psychosocial reading that does not neglect failing social systems but rather pursues an open and reflective, yet critical, mindfulness when listening to talk.
- Full Text:
- Date Issued: 2020
Structural Characterization of Carbonic Anhydrase VIII and Effects of Missense Single Nucleotide Variations to Protein Structure and Function:
- Sanyanga, Taremekedzwa Allan, Tastan Bishop, Özlem
- Authors: Sanyanga, Taremekedzwa Allan , Tastan Bishop, Özlem
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149670 , vital:38873 , https://doi.org/10.3390/ijms21082764
- Description: Human carbonic anhydrase 8 (CA-VIII) is an acatalytic isoform of the α -CA family. Though the protein cannot hydrate CO2, CA-VIII is essential for calcium (Ca2+) homeostasis within the body, and achieves this by allosterically inhibiting the binding of inositol 1,4,5-triphosphate (IP3) to the IP3 receptor type 1 (ITPR1) protein. However, the mechanism of interaction of CA-VIII to ITPR1 is not well understood. In addition, functional defects to CA-VIII due to non-synonymous single nucleotide polymorphisms (nsSNVs) result in Ca2+ dysregulation and the development of the phenotypes such as cerebellar ataxia, mental retardation and disequilibrium syndrome 3 (CAMRQ3). The pathogenesis of CAMRQ3 is also not well understood. The structure and function of CA-VIII was characterised, and pathogenesis of CAMRQ3 investigated. Structural and functional characterisation of CA-VIII was conducted through SiteMap and CPORT to identify potential binding site residues.
- Full Text:
- Date Issued: 2020
- Authors: Sanyanga, Taremekedzwa Allan , Tastan Bishop, Özlem
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149670 , vital:38873 , https://doi.org/10.3390/ijms21082764
- Description: Human carbonic anhydrase 8 (CA-VIII) is an acatalytic isoform of the α -CA family. Though the protein cannot hydrate CO2, CA-VIII is essential for calcium (Ca2+) homeostasis within the body, and achieves this by allosterically inhibiting the binding of inositol 1,4,5-triphosphate (IP3) to the IP3 receptor type 1 (ITPR1) protein. However, the mechanism of interaction of CA-VIII to ITPR1 is not well understood. In addition, functional defects to CA-VIII due to non-synonymous single nucleotide polymorphisms (nsSNVs) result in Ca2+ dysregulation and the development of the phenotypes such as cerebellar ataxia, mental retardation and disequilibrium syndrome 3 (CAMRQ3). The pathogenesis of CAMRQ3 is also not well understood. The structure and function of CA-VIII was characterised, and pathogenesis of CAMRQ3 investigated. Structural and functional characterisation of CA-VIII was conducted through SiteMap and CPORT to identify potential binding site residues.
- Full Text:
- Date Issued: 2020
Combining DNA barcoding and morphology to identify larval fishes from the nearshore environment off the south-east coast of South Africa
- Authors: Somana, Zinzi Sinazo
- Date: 2020
- Subjects: Fishes -- Larvae -- South Africa -- Identification , Fishes -- Genetics -- Research -- Technique , Fishes -- South Africa -- Classification , Genetic markers
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/144605 , vital:38362
- Description: The early life history stages of most marine fish species are undescribed. The problem is, most of these fishes have pelagic larvae which are minute, delicate forms. Linking the larval stage to an adult counterpart is extremely challenging as larvae are morphologically different from the adults. Historically, larval fish identification relied solely on distinguishing morphological characteristics and meristic measurements, which has resulted in taxonomic confusion and misidentification. The introduction of the deoxyribonucleic acid (DNA) barcoding technique as an alternative approach has been successful in positively identifying larval fishes. The correct identification of larval specimens is the key to a better understanding of larval ecology, which underpins the success of any adult fish population. This study aimed to positively identify larval fishes of the south-east coast of South Africa using morphological characteristics and DNA barcoding. Larval and eggs specimens for this study were collected from the shallow nearshore waters of the south-east coast of South Africa. A total of 177 larval specimens were used for morphological analysis. Body shape, gut shape, pigmentation and morphometric measurements (such as body depth, preanal length and total body length) were used to identify each specimen to the family level. In addition, a fragment of mitochondrial cytochrome c oxidase subunit 1 gene (COI) was adopted for sequencing to identify larval fish specimens and fish eggs. Sequences generated from this study were compared to those in the Barcode of Life Database (BOLD). When there were no close matches to a sequence, the GenBank nucleic acid sequence database, maintained by the National Center for Biotechnology Information (NCBI), was used as an alternative. A total of 18 different families were identified through morphology. Seventy-seven of the 177 larval specimens were not subjected to morphological identification due to physical damage. The majority of larvae identified using morphological characteristics belonged to either the Sparidae, Tripterygiidae or Gobiesocidae fish families. Through DNA barcoding, 12 fish families, 16 genera and 18 different species were identified. Ten DNA barcodes (categorised as ‘no match’) from 10 different larval specimens were not identified through any of the online databases. Therefore, the 2% threshold value was used to identify members of the same species. The K2P genetic distance relationships were calculated among the no match sequences and downloaded probability matches from NCBI. This resulted in two unknown specimens assigned to the Blenniidae and Gobiidae. All other taxa were identified to species level, except specimens representing the Gobiidae and Tripterygiidae families. Based on the K2P genetic distances Gobiidae representatives were categorised as members of the Caffrogobius genus. Twenty-eight barcodes represented specimens from the Tripterygiidae. DNA barcode data from COI was analysed using the standard phylogenetic procedures in MEGA6 to examine relationships and differentiation among sequences. These could not be identified to the lowest taxonomic rank due to limited sequence data to compare them with. The sequence data from these specimens gave different results in the two online databases. BOLD results were to family level (Tripterygiidae) and NCBI to the species level (Clinidae: Pavoclinus profundus). Results in this study confirmed the efficiency of the DNA barcoding technique in species level identification of fish larvae. The evidence from genetic barcodes of the Tripterygiidae specimens, supported by morphological characteristics, suggests the need for thorough research to identify the individuals to the species level. The fact that this study identified taxonomically problematic Gobiidae and Tripterygiidae specimens suggests that studies similar to this may highlight additional diversity and help to resolve the taxonomy of other species in these families. However, the lack of reference sequence data from the adult specimens, and especially those with cryptic diversity, were both shortcomings for the positive identification of larvae. With that being said, it shows the necessity for more research to be conducted on barcoding of larvae in general as to accommodate all kinds of species from biodiversity to economic perspectives.
- Full Text:
- Date Issued: 2020
- Authors: Somana, Zinzi Sinazo
- Date: 2020
- Subjects: Fishes -- Larvae -- South Africa -- Identification , Fishes -- Genetics -- Research -- Technique , Fishes -- South Africa -- Classification , Genetic markers
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/144605 , vital:38362
- Description: The early life history stages of most marine fish species are undescribed. The problem is, most of these fishes have pelagic larvae which are minute, delicate forms. Linking the larval stage to an adult counterpart is extremely challenging as larvae are morphologically different from the adults. Historically, larval fish identification relied solely on distinguishing morphological characteristics and meristic measurements, which has resulted in taxonomic confusion and misidentification. The introduction of the deoxyribonucleic acid (DNA) barcoding technique as an alternative approach has been successful in positively identifying larval fishes. The correct identification of larval specimens is the key to a better understanding of larval ecology, which underpins the success of any adult fish population. This study aimed to positively identify larval fishes of the south-east coast of South Africa using morphological characteristics and DNA barcoding. Larval and eggs specimens for this study were collected from the shallow nearshore waters of the south-east coast of South Africa. A total of 177 larval specimens were used for morphological analysis. Body shape, gut shape, pigmentation and morphometric measurements (such as body depth, preanal length and total body length) were used to identify each specimen to the family level. In addition, a fragment of mitochondrial cytochrome c oxidase subunit 1 gene (COI) was adopted for sequencing to identify larval fish specimens and fish eggs. Sequences generated from this study were compared to those in the Barcode of Life Database (BOLD). When there were no close matches to a sequence, the GenBank nucleic acid sequence database, maintained by the National Center for Biotechnology Information (NCBI), was used as an alternative. A total of 18 different families were identified through morphology. Seventy-seven of the 177 larval specimens were not subjected to morphological identification due to physical damage. The majority of larvae identified using morphological characteristics belonged to either the Sparidae, Tripterygiidae or Gobiesocidae fish families. Through DNA barcoding, 12 fish families, 16 genera and 18 different species were identified. Ten DNA barcodes (categorised as ‘no match’) from 10 different larval specimens were not identified through any of the online databases. Therefore, the 2% threshold value was used to identify members of the same species. The K2P genetic distance relationships were calculated among the no match sequences and downloaded probability matches from NCBI. This resulted in two unknown specimens assigned to the Blenniidae and Gobiidae. All other taxa were identified to species level, except specimens representing the Gobiidae and Tripterygiidae families. Based on the K2P genetic distances Gobiidae representatives were categorised as members of the Caffrogobius genus. Twenty-eight barcodes represented specimens from the Tripterygiidae. DNA barcode data from COI was analysed using the standard phylogenetic procedures in MEGA6 to examine relationships and differentiation among sequences. These could not be identified to the lowest taxonomic rank due to limited sequence data to compare them with. The sequence data from these specimens gave different results in the two online databases. BOLD results were to family level (Tripterygiidae) and NCBI to the species level (Clinidae: Pavoclinus profundus). Results in this study confirmed the efficiency of the DNA barcoding technique in species level identification of fish larvae. The evidence from genetic barcodes of the Tripterygiidae specimens, supported by morphological characteristics, suggests the need for thorough research to identify the individuals to the species level. The fact that this study identified taxonomically problematic Gobiidae and Tripterygiidae specimens suggests that studies similar to this may highlight additional diversity and help to resolve the taxonomy of other species in these families. However, the lack of reference sequence data from the adult specimens, and especially those with cryptic diversity, were both shortcomings for the positive identification of larvae. With that being said, it shows the necessity for more research to be conducted on barcoding of larvae in general as to accommodate all kinds of species from biodiversity to economic perspectives.
- Full Text:
- Date Issued: 2020
The impact of discounting fees by civil engineering consultants
- Authors: Siqiti, Khulile
- Date: 2020
- Subjects: Consulting engineers , Consultants Civil engineering , Project management
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/47246 , vital:39836
- Description: The study provides insight into the views and perceptions of consulting engineers on the discounting of professional fees. The purpose of the research was to determine the impact of discounting professional fees in the civil engineering profession and ultimately potential ways in which the civil engineering profession could improve business sustainability. The study included a review of literature, which was utilised to develop a questionnaire. A total of 26 practicing consulting engineers, who are members of Consulting Engineers South Africa (CESA), and represented small, medium and large consulting engineering firms, participated in the questionnaire survey. The questionnaire investigates the respondents’ perceptions on the impact of discounting professional fees in the civil engineering profession and the amount of discount offered as well as the reasons for discounting fees. The results show that the practice of discounting professional fees is widespread, affecting small, medium and large consulting firms. The results also indicate that prevailing market conditions in civil engineering profession are the primary reasons why consulting engineers offer discounts on fees. Respondents agreed that projects are awarded to the lowest bidder during tender process. Respondents also agreed that experienced engineers are allocated less time on projects to manage project costs. The findings suggest that discounting of professional fees is a great concern that needs to be addressed in order to attain profession business sustainability. It is suggested that the Engineering Council of South Africa (ECSA) should regulate the fee structures and ensure that all professionals, whether employed in the public or private sector, understand the basic finances on running a professional consultancy to deliver a service.
- Full Text:
- Date Issued: 2020
- Authors: Siqiti, Khulile
- Date: 2020
- Subjects: Consulting engineers , Consultants Civil engineering , Project management
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/47246 , vital:39836
- Description: The study provides insight into the views and perceptions of consulting engineers on the discounting of professional fees. The purpose of the research was to determine the impact of discounting professional fees in the civil engineering profession and ultimately potential ways in which the civil engineering profession could improve business sustainability. The study included a review of literature, which was utilised to develop a questionnaire. A total of 26 practicing consulting engineers, who are members of Consulting Engineers South Africa (CESA), and represented small, medium and large consulting engineering firms, participated in the questionnaire survey. The questionnaire investigates the respondents’ perceptions on the impact of discounting professional fees in the civil engineering profession and the amount of discount offered as well as the reasons for discounting fees. The results show that the practice of discounting professional fees is widespread, affecting small, medium and large consulting firms. The results also indicate that prevailing market conditions in civil engineering profession are the primary reasons why consulting engineers offer discounts on fees. Respondents agreed that projects are awarded to the lowest bidder during tender process. Respondents also agreed that experienced engineers are allocated less time on projects to manage project costs. The findings suggest that discounting of professional fees is a great concern that needs to be addressed in order to attain profession business sustainability. It is suggested that the Engineering Council of South Africa (ECSA) should regulate the fee structures and ensure that all professionals, whether employed in the public or private sector, understand the basic finances on running a professional consultancy to deliver a service.
- 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
A tribute to you
- Ndlebe-September, Thobeka Veronica
- Authors: Ndlebe-September, Thobeka Veronica
- Date: 2020
- Subjects: South African fiction (English) -- 21st century , South African fiction (English) -- History and criticism , Short stories, South African (English) -- 21st century , Xhosa fiction -- 21st century , Xhosa fiction -- History and criticism , Short stories, Xhosa -- 21st century , Diaries -- Authorship
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/144989 , vital:38398
- Description: My collection of short stories reflects my interest in narrative biblical fiction, allegorical stories about people and nature that resonate with our daily lives. I have been greatly influenced by writers such as Joel Matlou, Flannery O’Connor, Barry Gifford, Miriam Tladi and Leah Harris amongst others. I have also been captivated by fairy tales and folk tales, and also the work of isiXhosa writers such as S. E. K. Mqhayi, Madiponi Masenya, and Hulisani Ramantswana. I have discovered that I can borrow certain styles and forms of writing to enhance my own stories which are situated within ‘local’ contexts such as education, poverty, employment, the body, life and death.
- Full Text:
- Date Issued: 2020
- Authors: Ndlebe-September, Thobeka Veronica
- Date: 2020
- Subjects: South African fiction (English) -- 21st century , South African fiction (English) -- History and criticism , Short stories, South African (English) -- 21st century , Xhosa fiction -- 21st century , Xhosa fiction -- History and criticism , Short stories, Xhosa -- 21st century , Diaries -- Authorship
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/144989 , vital:38398
- Description: My collection of short stories reflects my interest in narrative biblical fiction, allegorical stories about people and nature that resonate with our daily lives. I have been greatly influenced by writers such as Joel Matlou, Flannery O’Connor, Barry Gifford, Miriam Tladi and Leah Harris amongst others. I have also been captivated by fairy tales and folk tales, and also the work of isiXhosa writers such as S. E. K. Mqhayi, Madiponi Masenya, and Hulisani Ramantswana. I have discovered that I can borrow certain styles and forms of writing to enhance my own stories which are situated within ‘local’ contexts such as education, poverty, employment, the body, life and death.
- Full Text:
- Date Issued: 2020
Covalent attachment of cobalt (II) tetra-(3-carboxyphenoxy) phthalocyanine onto pre-grafted gold electrode for the determination of catecholamine neurotransmitters:
- Tshenkeng, Keamogetse, Mashazi, Philani N
- Authors: Tshenkeng, Keamogetse , Mashazi, Philani N
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/163521 , vital:41045 , https://doi.org/10.1016/j.electacta.2020.137015
- Description: The fabrication of electroactive thin films onto gold electrode surfaces yields very interesting surfaces with excellent electrocatalytic activity. Cobalt (II) tetra-(3-carboxyphenoxy) phthalocyanine (CoTCPhOPc) was successfully synthesized and fully characterized using FT-IR spectroscopy, ultraviolet-visible (UV–Vis) spectroscopy, magnetic circular dichroism (MCD) spectroscopy, elemental analysis, and mass spectrometry. The CoTCPhOPc was immobilized onto phenylethylamino (PEA) pre-grafted gold electrode surface, Au-PEA, using amide coupling reaction to obtain Au-PEA-CoTCPhOPc.
- Full Text:
- Date Issued: 2020
- Authors: Tshenkeng, Keamogetse , Mashazi, Philani N
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/163521 , vital:41045 , https://doi.org/10.1016/j.electacta.2020.137015
- Description: The fabrication of electroactive thin films onto gold electrode surfaces yields very interesting surfaces with excellent electrocatalytic activity. Cobalt (II) tetra-(3-carboxyphenoxy) phthalocyanine (CoTCPhOPc) was successfully synthesized and fully characterized using FT-IR spectroscopy, ultraviolet-visible (UV–Vis) spectroscopy, magnetic circular dichroism (MCD) spectroscopy, elemental analysis, and mass spectrometry. The CoTCPhOPc was immobilized onto phenylethylamino (PEA) pre-grafted gold electrode surface, Au-PEA, using amide coupling reaction to obtain Au-PEA-CoTCPhOPc.
- Full Text:
- Date Issued: 2020
A holistic approach in understanding the effects of dietary protein sources on the growth and reproductive development of farmed abalone, Haliotis midae
- Wu, Yu
- Authors: Wu, Yu
- Date: 2020
- Subjects: Abalones -- Nutrition , Abalones -- Reproduction , Abalones -- Growth , Abalone culture , Haliotis midae -- Nutrition , Haliotis midae -- Reproduction , Haliotis midae -- Growth , Haliotis midae fisheries
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167719 , vital:41506
- Description: The combination of fishmeal and soya in the formulated feed of farmed South African abalone, Haliotis midae, not only improved abalone growth, but also the sustainability of the compound diets by reducing the reliance on fishmeal. However, the presence of soya produced larger gonads compared to those of abalone fed kelp or single-source protein diets. There is an increasing drive to control sexual maturation and reduce undesirable spawning events in farmed abalone. However, the reasons for the reported effects of soya inclusion on the reproductive development of farmed H. midae remain unresolved. The aim of this research was to use a combination of techniques to contribute to the understanding of the relationship between growth, reproductive and nutritional physiology of farmed H. midae fed diets of varying protein sources. These techniques included stable isotope analysis (SIA), fatty acid analysis, gonad histological assessments and haemolymph sexsteroid hormone analysis. The objectives were to examine the allocation of protein and nutritional components to somatic and reproductive tissues. This study also included the first attempt to investigate the role that sex steroid hormones play during gametogenesis. Abalone (40 – 50 g abalone-1) were fed one of four diets: either a single-source protein-based diet, i.e., (1) fishmeal-only (FM) or (2) soya-only (S), or a combination diet of (3) fishmeal-soya (FM S) or (4) fishmeal-sunflower meal (FM SM). Sampling occurred in 45-day intervals over one year. Dietary protein source had an effect on the growth of abalone, with enhancements in growth linked to the combination of fishmeal and a plant-protein source. The fishmeal ingredient was the most utilised protein source throughout the temporal changes in protein allocation into somatic and reproductive tissue, followed by soya and then sunflower meal. The mean whole- body mass of abalone was significantly influenced by an interaction between time and dietary treatment, with average whole-body mass changing differently over time between treatments (RM-ANOVA, F(24, 96) = 2.13, p = 0.005). Overall, abalone that were fed FM S had higher mean whole-body mass values than abalone that were fed the single-protein based diets, while abalone that were fed FM SM were similar to animals from all dietary treatments (RMANOVA, F(3, 12) = 5.75, p = 0.01). Male abalone had significantly higher gonad bulk index (GBI) values compared to females (RM-ANOVA, F(1, 24) = 49.03, p < 0.001) and this was independent of dietary treatment. Within each sex, female abalone fed the FM S diet (15.92 ± 1.88 mm3 g-1) had significantly higher GBI values than abalone fed S (9.76 ± 1.08 mm3 g-1), while abalone fed FM (11.96 ± 1.71 mm3 g-1) and FM SM (11.90 ± 0.80 mm3 g-1) were similar to abalone from all other dietary treatments (Tukey’s HSD, p < 0.05). Male abalone fed the FM S (21.59 ± 2.10 mm3 g-1) and FM SM diet (19.30 ± 2.63 mm3 g-1) had similar GBI values and they were significantly higher than in abalone fed the S diet (14.74 ± 1.27 mm3 g-1), while abalone fed FM S had significantly higher GBI values than abalone that consumed the FM diet (15.08 ±1.63mm3 g-1) ( Tukey’s HSD, p < 0.05). Although sunflower meal was poorly utilised, it produced similar overall growth to abalone that were fed the FM S diets. Yet, feed conversion ratio values were significantly lower for abalone fed FM S (1.30 ± 0.13) compared to those in the other three treatments, with ratios ranging from 1.65 – 1.72 over the one-year. The fatty acid compositions of the somatic and gonadal tissues were similar between treatments (PERMANOVA, p = 0.21), while fatty acid composition was influenced by sampling day, tissue type and abalone sex (PERMANOVA, p < 0.05). The essential fatty acids (EFAs) eicosadienoic acid and a-linolenic acid were present in abalone tissue, but they were not detected in the diets, suggesting the important role that an alternate food source (e.g. farmed abalone also had access to diatoms) may have played and the ability that H. midae may have in converting long-chain polyunsaturated fatty acids from C18 precursors. A change in the abundance of EFAs in the gonad tissue during highest and lowest GBI values suggested that arachidonic, eicosapentaenoic, g-linolenic and linoleic acid were important in females, while eicosapentaenoic, eicosadienoic and a-linolenic acid were important for male reproductive development. Dietary protein sources had an effect on the frequency distribution of maturity stages, where females that were fed FM S produced more ripe gonads and more males that were fed FM SM contained testes that showed signs of ripeness over the one-year study. Although dietary protein influenced the sex steroid concentrations in females and males, exhibiting fluctuations throughout the one-year period, no distinct pattern linked to gametogenesis were observed. The results from this study illustrate: (1) the importance of conducting laboratory studies when implementing SIA and mixing models in aquaculture nutrition; (2) conducting nutritional studies on mature, grow-out abalone; and (3) assessing the importance of naturally occurring diatoms in their diet and their contribution to growth and reproduction. The novel contribution of this research towards abalone nutritional physiology, the implications of these findings to industry as well as potential considerations for future studies were addressed.
- Full Text:
- Date Issued: 2020
- Authors: Wu, Yu
- Date: 2020
- Subjects: Abalones -- Nutrition , Abalones -- Reproduction , Abalones -- Growth , Abalone culture , Haliotis midae -- Nutrition , Haliotis midae -- Reproduction , Haliotis midae -- Growth , Haliotis midae fisheries
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167719 , vital:41506
- Description: The combination of fishmeal and soya in the formulated feed of farmed South African abalone, Haliotis midae, not only improved abalone growth, but also the sustainability of the compound diets by reducing the reliance on fishmeal. However, the presence of soya produced larger gonads compared to those of abalone fed kelp or single-source protein diets. There is an increasing drive to control sexual maturation and reduce undesirable spawning events in farmed abalone. However, the reasons for the reported effects of soya inclusion on the reproductive development of farmed H. midae remain unresolved. The aim of this research was to use a combination of techniques to contribute to the understanding of the relationship between growth, reproductive and nutritional physiology of farmed H. midae fed diets of varying protein sources. These techniques included stable isotope analysis (SIA), fatty acid analysis, gonad histological assessments and haemolymph sexsteroid hormone analysis. The objectives were to examine the allocation of protein and nutritional components to somatic and reproductive tissues. This study also included the first attempt to investigate the role that sex steroid hormones play during gametogenesis. Abalone (40 – 50 g abalone-1) were fed one of four diets: either a single-source protein-based diet, i.e., (1) fishmeal-only (FM) or (2) soya-only (S), or a combination diet of (3) fishmeal-soya (FM S) or (4) fishmeal-sunflower meal (FM SM). Sampling occurred in 45-day intervals over one year. Dietary protein source had an effect on the growth of abalone, with enhancements in growth linked to the combination of fishmeal and a plant-protein source. The fishmeal ingredient was the most utilised protein source throughout the temporal changes in protein allocation into somatic and reproductive tissue, followed by soya and then sunflower meal. The mean whole- body mass of abalone was significantly influenced by an interaction between time and dietary treatment, with average whole-body mass changing differently over time between treatments (RM-ANOVA, F(24, 96) = 2.13, p = 0.005). Overall, abalone that were fed FM S had higher mean whole-body mass values than abalone that were fed the single-protein based diets, while abalone that were fed FM SM were similar to animals from all dietary treatments (RMANOVA, F(3, 12) = 5.75, p = 0.01). Male abalone had significantly higher gonad bulk index (GBI) values compared to females (RM-ANOVA, F(1, 24) = 49.03, p < 0.001) and this was independent of dietary treatment. Within each sex, female abalone fed the FM S diet (15.92 ± 1.88 mm3 g-1) had significantly higher GBI values than abalone fed S (9.76 ± 1.08 mm3 g-1), while abalone fed FM (11.96 ± 1.71 mm3 g-1) and FM SM (11.90 ± 0.80 mm3 g-1) were similar to abalone from all other dietary treatments (Tukey’s HSD, p < 0.05). Male abalone fed the FM S (21.59 ± 2.10 mm3 g-1) and FM SM diet (19.30 ± 2.63 mm3 g-1) had similar GBI values and they were significantly higher than in abalone fed the S diet (14.74 ± 1.27 mm3 g-1), while abalone fed FM S had significantly higher GBI values than abalone that consumed the FM diet (15.08 ±1.63mm3 g-1) ( Tukey’s HSD, p < 0.05). Although sunflower meal was poorly utilised, it produced similar overall growth to abalone that were fed the FM S diets. Yet, feed conversion ratio values were significantly lower for abalone fed FM S (1.30 ± 0.13) compared to those in the other three treatments, with ratios ranging from 1.65 – 1.72 over the one-year. The fatty acid compositions of the somatic and gonadal tissues were similar between treatments (PERMANOVA, p = 0.21), while fatty acid composition was influenced by sampling day, tissue type and abalone sex (PERMANOVA, p < 0.05). The essential fatty acids (EFAs) eicosadienoic acid and a-linolenic acid were present in abalone tissue, but they were not detected in the diets, suggesting the important role that an alternate food source (e.g. farmed abalone also had access to diatoms) may have played and the ability that H. midae may have in converting long-chain polyunsaturated fatty acids from C18 precursors. A change in the abundance of EFAs in the gonad tissue during highest and lowest GBI values suggested that arachidonic, eicosapentaenoic, g-linolenic and linoleic acid were important in females, while eicosapentaenoic, eicosadienoic and a-linolenic acid were important for male reproductive development. Dietary protein sources had an effect on the frequency distribution of maturity stages, where females that were fed FM S produced more ripe gonads and more males that were fed FM SM contained testes that showed signs of ripeness over the one-year study. Although dietary protein influenced the sex steroid concentrations in females and males, exhibiting fluctuations throughout the one-year period, no distinct pattern linked to gametogenesis were observed. The results from this study illustrate: (1) the importance of conducting laboratory studies when implementing SIA and mixing models in aquaculture nutrition; (2) conducting nutritional studies on mature, grow-out abalone; and (3) assessing the importance of naturally occurring diatoms in their diet and their contribution to growth and reproduction. The novel contribution of this research towards abalone nutritional physiology, the implications of these findings to industry as well as potential considerations for future studies were addressed.
- 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
Defect Classification in Photovoltaic Modules through Thermal Infrared Imaging using Machine Learning
- Dunderdale, Christopher, Clohessy, C M
- Authors: Dunderdale, Christopher , Clohessy, C M
- Date: 2020
- Subjects: Photovoltaic power generation -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/48280 , vital:40838
- Description: As the global energy demand continues to soar, solar energy has become an attractive and environmentally conscious method to meet this demand. This study examines the use of machine learning techniques for defect detection and classification in photovoltaic systems using thermal infrared images. A deep learning and feature-based approach is also investigated for the purpose of detecting and classifying defective photovoltaic modules. The VGG-16 and MobileNet deep learning models are shown to provide good performance for the classification of defects. The scale invariant feature transform (SIFT) descriptor, combined with the random forest and support vector machine classifier, is also used to discriminate between defective and non-defective photovoltaic modules in a South African setting. The successful implementation of this approach has significant potential for cost reduction in defect classification over currently available methods.
- Full Text:
- Date Issued: 2020
- Authors: Dunderdale, Christopher , Clohessy, C M
- Date: 2020
- Subjects: Photovoltaic power generation -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/48280 , vital:40838
- Description: As the global energy demand continues to soar, solar energy has become an attractive and environmentally conscious method to meet this demand. This study examines the use of machine learning techniques for defect detection and classification in photovoltaic systems using thermal infrared images. A deep learning and feature-based approach is also investigated for the purpose of detecting and classifying defective photovoltaic modules. The VGG-16 and MobileNet deep learning models are shown to provide good performance for the classification of defects. The scale invariant feature transform (SIFT) descriptor, combined with the random forest and support vector machine classifier, is also used to discriminate between defective and non-defective photovoltaic modules in a South African setting. The successful implementation of this approach has significant potential for cost reduction in defect classification over currently available methods.
- Full Text:
- Date Issued: 2020
Synthesis of pH sensitive dual capped CdTe QDs: their optical properties and structural morphology
- Daramola, Olamide A, Noundou, Xavier S, Nkanga, Christian I, Tseki, Potlaki F, Krause, Rui W M
- Authors: Daramola, Olamide A , Noundou, Xavier S , Nkanga, Christian I , Tseki, Potlaki F , Krause, Rui W M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156364 , vital:39983 , https://doi.org/10.1007/s10895-020-02526-x
- Description: We herein report five different types of thiol dual capped cadmium tellurite quantum dots (CdTe QDs) namely glutathionemercapto-propanoic acid (QD 1), glutathione-thiolglycolic acid (QD 2), L-cysteine-mercapto-propanoic acid (QD 3), L-cysteinethiol-glycolic acid (QD 4) and mercapto-propanoic acid-thiol-glycolic (QD 5). Dual-capped CdTe QDs were prepared using a one pot synthetic method. Cadmium acetate and sodium tellurite were respectively used as cadmium and tellurium precursors. Photo-physical properties of the synthesized QDs were examined using UV-Vis and photoluminescence spectroscopy while structural characterization was performed by means of transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy.
- Full Text:
- Date Issued: 2020
- Authors: Daramola, Olamide A , Noundou, Xavier S , Nkanga, Christian I , Tseki, Potlaki F , Krause, Rui W M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156364 , vital:39983 , https://doi.org/10.1007/s10895-020-02526-x
- Description: We herein report five different types of thiol dual capped cadmium tellurite quantum dots (CdTe QDs) namely glutathionemercapto-propanoic acid (QD 1), glutathione-thiolglycolic acid (QD 2), L-cysteine-mercapto-propanoic acid (QD 3), L-cysteinethiol-glycolic acid (QD 4) and mercapto-propanoic acid-thiol-glycolic (QD 5). Dual-capped CdTe QDs were prepared using a one pot synthetic method. Cadmium acetate and sodium tellurite were respectively used as cadmium and tellurium precursors. Photo-physical properties of the synthesized QDs were examined using UV-Vis and photoluminescence spectroscopy while structural characterization was performed by means of transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy.
- Full Text:
- Date Issued: 2020
Simultaneous liposomal encapsulation of antibiotics and proteins: co-loading and characterization of rifampicin and Human Serum Albumin in soy-liposomes
- Bapolisi, Alain M, Nkanga, Christian I, Walker, Roderick B, Krause, Rui W M
- Authors: Bapolisi, Alain M , Nkanga, Christian I , Walker, Roderick B , Krause, Rui W M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148617 , vital:38755 , https://doi.org/10.1016/j.jddst.2020.101751
- Description: The recurrent development of resistance to antimicrobial agents threatens the ability for successful treatment of infectious diseases. Hydrophobic antibiotics such as rifampicin (Rif) are particularly affected due to poor bioavailability. On the other hand, proteins play important roles in drug delivery and release. Further, the combination of antimicrobials with therapeutic proteins and their encapsulation in liposomes seems a promising approach for improvement of antimicrobial efficacy. This study aimed to encapsulate Rif simultaneously with a large protein, Human Serum Albumin (HSA) in liposomes made from an inexpensive crude soy lecithin (CSL).
- Full Text:
- Date Issued: 2020
- Authors: Bapolisi, Alain M , Nkanga, Christian I , Walker, Roderick B , Krause, Rui W M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148617 , vital:38755 , https://doi.org/10.1016/j.jddst.2020.101751
- Description: The recurrent development of resistance to antimicrobial agents threatens the ability for successful treatment of infectious diseases. Hydrophobic antibiotics such as rifampicin (Rif) are particularly affected due to poor bioavailability. On the other hand, proteins play important roles in drug delivery and release. Further, the combination of antimicrobials with therapeutic proteins and their encapsulation in liposomes seems a promising approach for improvement of antimicrobial efficacy. This study aimed to encapsulate Rif simultaneously with a large protein, Human Serum Albumin (HSA) in liposomes made from an inexpensive crude soy lecithin (CSL).
- Full Text:
- Date Issued: 2020
Narratives of the commuter: experiences of commuting in the Port Elizabeth Northern Areas
- Authors: Lingham, Rochin Shelley
- Date: 2020
- Subjects: Commuters -- South Africa --Port Elizbeth , Traffic Safefty -- South Africa --Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/46911 , vital:39731
- Description: Transportation is a fundamental element of human existence. As urban areas continue to grow at a rapid speed public transport increasingly takes on the role of providing citizens with access to participate in activities of the city. Research has shown that individual perception of public transport is influenced by passenger response to collective mobility when on board modes of transport. This study aimed to investigate the minibus taxi commuters’ constructions and relevance of their taxi commuting experiences in the Port Elizabeth Northern Areas. Building on existing work it asks: How do commuters in the Northern Areas of Port Elizabeth describe and narrate their taxi commuting experiences? This thesis is interested in the experience of public transport as told by those who make use of the industry. The study focuses on both commuters and drivers and the way they characterize the social experience of commuting in taxis. These individuals provide first-hand experience and insight of the industry. The purpose of this study is to foreground the voices of those who have first-hand experience of dependency on the public transport industry.It is these voices that must be heard and considered in policy formation. The study found simultaneous vulnerabilities exist between taxi drivers and taxi commuters resulting in both groups being held captive by the taxi industry.
- Full Text:
- Date Issued: 2020
- Authors: Lingham, Rochin Shelley
- Date: 2020
- Subjects: Commuters -- South Africa --Port Elizbeth , Traffic Safefty -- South Africa --Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/46911 , vital:39731
- Description: Transportation is a fundamental element of human existence. As urban areas continue to grow at a rapid speed public transport increasingly takes on the role of providing citizens with access to participate in activities of the city. Research has shown that individual perception of public transport is influenced by passenger response to collective mobility when on board modes of transport. This study aimed to investigate the minibus taxi commuters’ constructions and relevance of their taxi commuting experiences in the Port Elizabeth Northern Areas. Building on existing work it asks: How do commuters in the Northern Areas of Port Elizabeth describe and narrate their taxi commuting experiences? This thesis is interested in the experience of public transport as told by those who make use of the industry. The study focuses on both commuters and drivers and the way they characterize the social experience of commuting in taxis. These individuals provide first-hand experience and insight of the industry. The purpose of this study is to foreground the voices of those who have first-hand experience of dependency on the public transport industry.It is these voices that must be heard and considered in policy formation. The study found simultaneous vulnerabilities exist between taxi drivers and taxi commuters resulting in both groups being held captive by the taxi industry.
- Full Text:
- Date Issued: 2020
The role of flexible working in achieving a work-life balance: a case study of information technology consultants of Kestrel Business Solutions – London, United Kingdom
- Authors: Nyamujara, Tinashe
- Date: 2020
- Subjects: Kestrel Business Solutions , Flexible work arrangement -- Case studies , Work-life balance , Flexitime , Telecommunting , Telecommunting -- Case studies
- Language: English
- Type: text , Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/167245 , vital:41459
- Description: This research was a Case Study on the role of Flexible Working in achieving a Work – Life Balance, based on the Information Technology Consultants of Kestrel Business Solutions – a company based in London, the United Kingdom. The study set out to determine what aspects of flexible working can reduce work - related stress; home - related stress; improve personal wellbeing; identify the pitfalls of flexible working, and to recommend mitigating actions. The literature review identified five different, but complimentary theories that included: The Spill over Theory; Balanced Theory; Resource Based Theory; Compensation Theory and the Wellness Theory to unpack and explore the concept of Work - Life Balance. The study followed a predominantly qualitative methodology approach and used thematic analysis to identify key ideas from the data. Interviews and questionnaires were used to obtain data from the respondents, in addition to being a data triangulation exercise. From a population of 10 subjects - purposeful sampling was used to select a sample of 10 respondents - made up of 3 males and 7 females. All respondents were employees of Kestrel Business Solutions. 6 respondents were interviewed and given questionnaires to fill out. 6 face to face interviews were conducted, and 6 questionnaires completed until saturation was achieved - indicating a survey response rate of 100%. The results from the data collection generally showed how aspects of flexible working like telecommuting, flexitime and homeworking ultimately helped the employees to achieve a Work-Life Balance - by primarily influencing how they balanced their work, home, and personal commitments. Importantly, the study also identified pitfalls of flexible working; like employees feeling isolated and the pressure to perform. Potential mitigating efforts identified in the study included, providing more company support and education for flexible working initiatives. The study concluded by acknowledging the limitations of the study, which included time constraints and the small population, and sample size of the study. In its conclusion, the study identified recommendations for future studies like: increasing the population and sample size, and devoting more time to the study, for more generalized and conclusive findings.
- Full Text:
- Date Issued: 2020
- Authors: Nyamujara, Tinashe
- Date: 2020
- Subjects: Kestrel Business Solutions , Flexible work arrangement -- Case studies , Work-life balance , Flexitime , Telecommunting , Telecommunting -- Case studies
- Language: English
- Type: text , Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/167245 , vital:41459
- Description: This research was a Case Study on the role of Flexible Working in achieving a Work – Life Balance, based on the Information Technology Consultants of Kestrel Business Solutions – a company based in London, the United Kingdom. The study set out to determine what aspects of flexible working can reduce work - related stress; home - related stress; improve personal wellbeing; identify the pitfalls of flexible working, and to recommend mitigating actions. The literature review identified five different, but complimentary theories that included: The Spill over Theory; Balanced Theory; Resource Based Theory; Compensation Theory and the Wellness Theory to unpack and explore the concept of Work - Life Balance. The study followed a predominantly qualitative methodology approach and used thematic analysis to identify key ideas from the data. Interviews and questionnaires were used to obtain data from the respondents, in addition to being a data triangulation exercise. From a population of 10 subjects - purposeful sampling was used to select a sample of 10 respondents - made up of 3 males and 7 females. All respondents were employees of Kestrel Business Solutions. 6 respondents were interviewed and given questionnaires to fill out. 6 face to face interviews were conducted, and 6 questionnaires completed until saturation was achieved - indicating a survey response rate of 100%. The results from the data collection generally showed how aspects of flexible working like telecommuting, flexitime and homeworking ultimately helped the employees to achieve a Work-Life Balance - by primarily influencing how they balanced their work, home, and personal commitments. Importantly, the study also identified pitfalls of flexible working; like employees feeling isolated and the pressure to perform. Potential mitigating efforts identified in the study included, providing more company support and education for flexible working initiatives. The study concluded by acknowledging the limitations of the study, which included time constraints and the small population, and sample size of the study. In its conclusion, the study identified recommendations for future studies like: increasing the population and sample size, and devoting more time to the study, for more generalized and conclusive findings.
- 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