A critical analysis of the establishment, conceptualisation, design and curriculum component selection of Master of Education programmes at selected Tanzanian universities
- Authors: Ramadhan, Maryam Khamis
- Date: 2018
- Subjects: Master of education degree Tanzania , Universities and colleges Curricula Tanzania , Universities and colleges Evaluation , Teacher effectiveness Tanzania , Master of education degree , Educational change Tanzania , Secondary school teachers Tanzania , Pedagogical content knowledge Tanzania , Universities and colleges Administration , Critical realism
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62214 , vital:28139
- Description: There is a dearth of research on how the design and curriculum of a Master of Education (MEd) qualification for university-based teacher educators of prospective secondary school teachers may or may not contribute to the problem of poor secondary school learning outcomes in Tanzania. This qualitative study analyses the establishment, conceptualisation, design and curriculum components of selected MEd programmes with the purpose of identifying and explaining the conditions enabling and/or constraining the development of quality teacher educators. The research used a case study design to investigate how and why particular knowledge is privileged in two MEd programmes at two Tanzanian universities with a view to probing the relevance of the knowledge to teacher educators professional roles and practices. The study used critical realism as an under-labourer to investigate power structures and the generative and causal mechanisms underlying the two MEd programmes. The study draws on aspects of Bernstein’s theory as analytical tools to explain what emerges from the data. The data was collected from interviews, document analysis and observation, and analysed using thematic analysis, abductive and retroductive modes of inference. The research revealed and explains how underlying structural and agential mechanisms have shaped the establishment, conceptualisation and curriculum design of the two MEd programmes. The findings revealed a strong relationship between constraints, including the lack of appropriate MEd design team and the inadequacy of resources and facilities, and the quality of MEd graduates. Such constrains are possible mechanisms associated with the agential actions of the top administrators affect the relevance and appropriateness of the MEd curriculum components, the effective lecturers transmission and students acquisition of knowledge and skills. The research also explored how underlying mechanisms shaped the selection of course content and the privileging of certain types of teacher knowledge. These mechanisms include programme entry qualification, curriculum arrangement of core and elective courses, the lack of awareness of the knowledge and skills requisite for teacher educators’ specialisation, and the absence of recontextualisation principles to guide appropriate selection and recontextualisation of the relevant teacher educator’s courses. There is evidence that both MEd programmes have insufficient pedagogical knowledge and lack large components of academic content knowledge of teaching. An emphasis on individual disciplinary education courses with strong boundaries between modules and topics, aimed at developing specific education specialisations, results in teacher educator professional knowledge being less developed. Furthermore the accumulation and repetition of inappropriate knowledge has resulted in these programmes being weak regions for teacher educators’ professional fields of practice. This has implications for the quality of the secondary school teacher professional development courses on which these MEd graduates teach. It raises questions about the quality of the secondary school teachers being produced, and the extent to which this is contributing to the disappointing performance of Tanzanian schooling. The study generates insights into the mechanisms and conditions constraining the development of quality teacher educators. These conditions include the domination of higher education by customer demand, weak university regulatory systems, and the autonomy of university administration in terms of programme approval and other academic operations. Some administrators and lecturers showed an understanding of what would enable quality teacher educator development in the MEd programme. The findings of the research may help to strengthen and enhance quality assurance in the Master of Education programmes for teacher educators in Tanzania in ways that help develop quality secondary school teachers and improve school learning outcomes.
- Full Text:
- Date Issued: 2018
- Authors: Ramadhan, Maryam Khamis
- Date: 2018
- Subjects: Master of education degree Tanzania , Universities and colleges Curricula Tanzania , Universities and colleges Evaluation , Teacher effectiveness Tanzania , Master of education degree , Educational change Tanzania , Secondary school teachers Tanzania , Pedagogical content knowledge Tanzania , Universities and colleges Administration , Critical realism
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62214 , vital:28139
- Description: There is a dearth of research on how the design and curriculum of a Master of Education (MEd) qualification for university-based teacher educators of prospective secondary school teachers may or may not contribute to the problem of poor secondary school learning outcomes in Tanzania. This qualitative study analyses the establishment, conceptualisation, design and curriculum components of selected MEd programmes with the purpose of identifying and explaining the conditions enabling and/or constraining the development of quality teacher educators. The research used a case study design to investigate how and why particular knowledge is privileged in two MEd programmes at two Tanzanian universities with a view to probing the relevance of the knowledge to teacher educators professional roles and practices. The study used critical realism as an under-labourer to investigate power structures and the generative and causal mechanisms underlying the two MEd programmes. The study draws on aspects of Bernstein’s theory as analytical tools to explain what emerges from the data. The data was collected from interviews, document analysis and observation, and analysed using thematic analysis, abductive and retroductive modes of inference. The research revealed and explains how underlying structural and agential mechanisms have shaped the establishment, conceptualisation and curriculum design of the two MEd programmes. The findings revealed a strong relationship between constraints, including the lack of appropriate MEd design team and the inadequacy of resources and facilities, and the quality of MEd graduates. Such constrains are possible mechanisms associated with the agential actions of the top administrators affect the relevance and appropriateness of the MEd curriculum components, the effective lecturers transmission and students acquisition of knowledge and skills. The research also explored how underlying mechanisms shaped the selection of course content and the privileging of certain types of teacher knowledge. These mechanisms include programme entry qualification, curriculum arrangement of core and elective courses, the lack of awareness of the knowledge and skills requisite for teacher educators’ specialisation, and the absence of recontextualisation principles to guide appropriate selection and recontextualisation of the relevant teacher educator’s courses. There is evidence that both MEd programmes have insufficient pedagogical knowledge and lack large components of academic content knowledge of teaching. An emphasis on individual disciplinary education courses with strong boundaries between modules and topics, aimed at developing specific education specialisations, results in teacher educator professional knowledge being less developed. Furthermore the accumulation and repetition of inappropriate knowledge has resulted in these programmes being weak regions for teacher educators’ professional fields of practice. This has implications for the quality of the secondary school teacher professional development courses on which these MEd graduates teach. It raises questions about the quality of the secondary school teachers being produced, and the extent to which this is contributing to the disappointing performance of Tanzanian schooling. The study generates insights into the mechanisms and conditions constraining the development of quality teacher educators. These conditions include the domination of higher education by customer demand, weak university regulatory systems, and the autonomy of university administration in terms of programme approval and other academic operations. Some administrators and lecturers showed an understanding of what would enable quality teacher educator development in the MEd programme. The findings of the research may help to strengthen and enhance quality assurance in the Master of Education programmes for teacher educators in Tanzania in ways that help develop quality secondary school teachers and improve school learning outcomes.
- Full Text:
- Date Issued: 2018
A critique of language policy and implementation strategies used in selected institutions of higher learning in South Africa
- Authors: Somlata, Zakhile
- Date: 2018
- Subjects: Language policy South Africa , Translanguaging (Linguistics) , Language and education South Africa , Language and languages Study and teaching South Africa , Education, Higher South Africa , Multilingualism South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62571 , vital:28208
- Description: This thesis evaluated the language policy implementation strategies used in selected universities of South Africa. The Constitution of the Republic of South African (1996) recognises eleven official languages, namely: English, Afrikaans, isiNdebele, isiXhosa, isiZulu, Sesotho, Setswana, SiSwati, Sepedi, Tshivenda and Xitsonga. These official languages should enjoy the parity of esteem in all domains. The language practices are very important in the education of students at all levels of education but this study focuses on the language policy implementation in universities. Most universities of South Africa have their language policies but the dilemma is on the implementation of those language policies. The overarching aim of this study is to evaluate how university use language policy for access and success of the students and to assess the language policy implementation strategies, monitoring and evaluation. The language is central to the success of the students and this study further investigated to what extent are the universities use the linguistic repertoires of the students in their education. This study is rooted in orientations of language planning: Language as problem, language as right and language as resource (Ruiz, 1984). This thesis employed a mixed methods approach (qualitative and quantitative method) with convergent parallel design. The data was collected from eleven universities of South Africa and the participants in each university were the "Key informants" (experts and insiders) which comprised of member of Executive Management, a member of the Institutional Language Committee and a language lecturer; and a cohort of forty third year students. The Key informants participated in the qualitative data collection through the structured interviews. The forty third year students participated in the quantitative data collected through survey questionnaires. The language policy documents of the universities were also sampled to get a better understanding of the real language practices and the language policy. The thematic analysis was used to analyse transcripts that were developed from the interviews, data from the students was analysed through descriptive and inferential analyses with Statistical Package for the Social Sciences (SPSS) as a statistical test and document analysis was used to analyse the language policies; The findings show that universities have commitment to access of the students to institutions of Higher Education. The success of the students is being thwarted by the monolingual approach where most of the universities use English only as the medium of instruction. The monolingual approach negatively affects the academic success and excellent academic performance of the majority of students. The findings show that there is high demand from the students that the course materials should be provided in African languages. All selected universities have their language policy which is something positive but most of them are outdated because they need to be reviewed at least after five years. The findings demonstrate that most universities lack the language policy implementation plans. The nonexistence of the language policy implementation plan adversely affects the implementation of the language policy. The study recommends that universities should provide the learning resources in African languages to meet the demands of the students. To maximise the success, students should be examined in any official languages of the university. The language policy implementation plans should be developed urgently so as to improve language policy implementation in universities. , Le thesisi iphonononge iindlela zokusetyenziswa komgaqo-nkqubo wolwimi kwiiyunivesithi ezichongiweyo zaseMzantsi Afrika. Umgaqo-siseko waseMzantsi Afrika (1996) athathela ingqalelo iilwimi ezisemthethweni ezilishumi elinanye, isiNgesi, isiBhulu, isiNdebele, isiXhosa, isiZulu, Sesotho, Setswana, Sepedi, SiSwati, Tshivenda neXitsonga. Ezi lwimi zisemthethweni zifanele ukuba zisetyenziswe ngokulinganayo kuzo zonke iinkalo. Ukusetyenziswa kweelwimi kubalulekile kakhulu kwimfundo yabantwana kuwo onke amanqanaba emfundo kodwa olu phando lugxile ekusetyenzisweni komgaqo-nkqubo wolwimi kwiiyunivesithi. Uninzi lweeyunivesithi zinayo imigaqo-nkqubo yolwimi kodwa ingxaki isekusetyenzisweni kwaloo migaqo-nkqubo yolwimi. Ezona njongo zolu phando kukuphonononga ukuba iiyunivesithi ziyisebenzisa njani na imigaqo-nkqubo yolwimi ukuze abafundi bafikelele kwaye baphumelele ezifundweni kwakhona nokugocagoca izicwangciso zokusetyenziswa komgaqo-nkqubo wolwimi nokuhlola ukusebenza kwezo zicwangciso. Ulwimi ngundoqo kwimpumelelo yabafundi kwaye umyinge wokusetyenziswa kweelwimi zabafundi ekufundeni kwabo kuthe kwaphandwa. Esi sifundo sisekelwe kwiindlela zocwangciso-lwimi: Ulwimi njengengxaki, ulwimi njengelungelo nolwimi njengesixhobo (Ruiz, 1984). Le thesisi esebenzise indlela yophando entlantlu-mbini (eyobunjani neyobungakanani) kunye noyilo lwendibaniso kokunxuseneyo. Idatha yathi yaqokelelwa kwiiyunivesithi ezilishumi elinanye eMzantsi Afrika kwaye abathabathi nxaxheba babandakanya ilungu lesigqeba solawulo, ilungu lekomiti yeelwimi eyunivesithi nomhlohli wolwimi; kunye nabafundi abakunyaka wesithathu kwizifundo zabo kwiyunivesithi nganye. Idatha yaqokelelwa kubadlulisi-lwazi abaphambili beeyunivesithi ngodliwano-ndlebe oluqingqiweyo. Abafundi abalishumi elinesine bathi bathabathi inxaxheba kuqokelelo lwedatha ngokuthi bagcwalise uludwe lwemibuzo eyayicwangcisiwe. Umaxwebhu omgaqo-nkqubo wolwimi athi achongwa ukuze kubekho ukuqondakala phakathi kokusetyenziswa kolwimi kunye nokumgaqo-nkqubo wolwimi. Uhlalutyo ngokomxholo lwathi lwasetyenziswa ukuhlalutya ulwazi olwabhalwayo luvela kudliwano-ndlebe olwashicilelwayo, idatha eyayisuka kubafundi yathi yahlalutywa ngokusebenzisa uhlalutyo ngokwenkcazelo nangokuthelekelela kunye neStatistical Pakage for Social Sciences (SPSS) njengesixhobo senkcukacha-manani kwaye uhlalutyo loxwebhu lwathi lwasetyenziswa ukuhlalutya imigaqo-nkqubo yolwimi. Iziphumo zibonakalisa ukuba iiyunivesithi zizibophelele ekufikelelekeni kwabafundi kumaziko emfundo ephakamileyo. Impumelelo yabafundi ithi ithityazwe kukusetyenziswa kolwimi olunye apho uninzi lweeyunivesithi zisebenzisa isiNgesi kuphela njengolwimi lokufunda nokufundisa. Ukusetyenziswa kolwimi olunye kuthi kuchaphazela gwenxa impumelelo yabafundi nokuqhuba ngcono ezifundweni. Iziphumo zibonakalisa ukuba kukho imfuno emmandla kubafundi yokuba izixhobo zokufunda nokufundisa zifumaneke nangeelwimi zesiNtu. Inyathelo elihle lelokuba zonke iiyunivesithi ezichongiweyo zinayo imigaqo-nkqubo yolwimi kodwa imigaqo-nkqubo yolwimi emininzi midala kuba ifanelwe ukuba iphononongwe emva kweminyaka emihlanu ubuncinane. Iziphumo zibonakalisa ukuba iiyunivesithi azinazo izicwangciso zokusetyenziswa kwemigaqo-nkqubo yolwimi. Ukungabikho kwesicwangciso sokusetyenziswa komgaqo-nkqubo wolwimi kuchaphazela gwenxa ukusetyenziswa kwawo. Olu phando lundulula ukuba iiyunivesithi zifanele ukuba zibonelele ngezixhobo zokufunda nokufundisa ezingeelwimi zesiNtu ukukhawulelana neemfuno zabafundi. Ukwandisa impumelelo, abafundi kufanele ukuba bavavanywe ngalo naluphi na ulwimi olusemthethweni lweyunivesithi. Izicwangciso zokusetyenziswa komgaqo-nkqubo wolwimi zifanele ukuba ziveliswe njengenyewe engxamisekileyo ukuze kuphuculwe ukusetyenziswa kwemigaqo- nkqubo yolwimi kwiiyunivesithi.
- Full Text:
- Date Issued: 2018
- Authors: Somlata, Zakhile
- Date: 2018
- Subjects: Language policy South Africa , Translanguaging (Linguistics) , Language and education South Africa , Language and languages Study and teaching South Africa , Education, Higher South Africa , Multilingualism South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62571 , vital:28208
- Description: This thesis evaluated the language policy implementation strategies used in selected universities of South Africa. The Constitution of the Republic of South African (1996) recognises eleven official languages, namely: English, Afrikaans, isiNdebele, isiXhosa, isiZulu, Sesotho, Setswana, SiSwati, Sepedi, Tshivenda and Xitsonga. These official languages should enjoy the parity of esteem in all domains. The language practices are very important in the education of students at all levels of education but this study focuses on the language policy implementation in universities. Most universities of South Africa have their language policies but the dilemma is on the implementation of those language policies. The overarching aim of this study is to evaluate how university use language policy for access and success of the students and to assess the language policy implementation strategies, monitoring and evaluation. The language is central to the success of the students and this study further investigated to what extent are the universities use the linguistic repertoires of the students in their education. This study is rooted in orientations of language planning: Language as problem, language as right and language as resource (Ruiz, 1984). This thesis employed a mixed methods approach (qualitative and quantitative method) with convergent parallel design. The data was collected from eleven universities of South Africa and the participants in each university were the "Key informants" (experts and insiders) which comprised of member of Executive Management, a member of the Institutional Language Committee and a language lecturer; and a cohort of forty third year students. The Key informants participated in the qualitative data collection through the structured interviews. The forty third year students participated in the quantitative data collected through survey questionnaires. The language policy documents of the universities were also sampled to get a better understanding of the real language practices and the language policy. The thematic analysis was used to analyse transcripts that were developed from the interviews, data from the students was analysed through descriptive and inferential analyses with Statistical Package for the Social Sciences (SPSS) as a statistical test and document analysis was used to analyse the language policies; The findings show that universities have commitment to access of the students to institutions of Higher Education. The success of the students is being thwarted by the monolingual approach where most of the universities use English only as the medium of instruction. The monolingual approach negatively affects the academic success and excellent academic performance of the majority of students. The findings show that there is high demand from the students that the course materials should be provided in African languages. All selected universities have their language policy which is something positive but most of them are outdated because they need to be reviewed at least after five years. The findings demonstrate that most universities lack the language policy implementation plans. The nonexistence of the language policy implementation plan adversely affects the implementation of the language policy. The study recommends that universities should provide the learning resources in African languages to meet the demands of the students. To maximise the success, students should be examined in any official languages of the university. The language policy implementation plans should be developed urgently so as to improve language policy implementation in universities. , Le thesisi iphonononge iindlela zokusetyenziswa komgaqo-nkqubo wolwimi kwiiyunivesithi ezichongiweyo zaseMzantsi Afrika. Umgaqo-siseko waseMzantsi Afrika (1996) athathela ingqalelo iilwimi ezisemthethweni ezilishumi elinanye, isiNgesi, isiBhulu, isiNdebele, isiXhosa, isiZulu, Sesotho, Setswana, Sepedi, SiSwati, Tshivenda neXitsonga. Ezi lwimi zisemthethweni zifanele ukuba zisetyenziswe ngokulinganayo kuzo zonke iinkalo. Ukusetyenziswa kweelwimi kubalulekile kakhulu kwimfundo yabantwana kuwo onke amanqanaba emfundo kodwa olu phando lugxile ekusetyenzisweni komgaqo-nkqubo wolwimi kwiiyunivesithi. Uninzi lweeyunivesithi zinayo imigaqo-nkqubo yolwimi kodwa ingxaki isekusetyenzisweni kwaloo migaqo-nkqubo yolwimi. Ezona njongo zolu phando kukuphonononga ukuba iiyunivesithi ziyisebenzisa njani na imigaqo-nkqubo yolwimi ukuze abafundi bafikelele kwaye baphumelele ezifundweni kwakhona nokugocagoca izicwangciso zokusetyenziswa komgaqo-nkqubo wolwimi nokuhlola ukusebenza kwezo zicwangciso. Ulwimi ngundoqo kwimpumelelo yabafundi kwaye umyinge wokusetyenziswa kweelwimi zabafundi ekufundeni kwabo kuthe kwaphandwa. Esi sifundo sisekelwe kwiindlela zocwangciso-lwimi: Ulwimi njengengxaki, ulwimi njengelungelo nolwimi njengesixhobo (Ruiz, 1984). Le thesisi esebenzise indlela yophando entlantlu-mbini (eyobunjani neyobungakanani) kunye noyilo lwendibaniso kokunxuseneyo. Idatha yathi yaqokelelwa kwiiyunivesithi ezilishumi elinanye eMzantsi Afrika kwaye abathabathi nxaxheba babandakanya ilungu lesigqeba solawulo, ilungu lekomiti yeelwimi eyunivesithi nomhlohli wolwimi; kunye nabafundi abakunyaka wesithathu kwizifundo zabo kwiyunivesithi nganye. Idatha yaqokelelwa kubadlulisi-lwazi abaphambili beeyunivesithi ngodliwano-ndlebe oluqingqiweyo. Abafundi abalishumi elinesine bathi bathabathi inxaxheba kuqokelelo lwedatha ngokuthi bagcwalise uludwe lwemibuzo eyayicwangcisiwe. Umaxwebhu omgaqo-nkqubo wolwimi athi achongwa ukuze kubekho ukuqondakala phakathi kokusetyenziswa kolwimi kunye nokumgaqo-nkqubo wolwimi. Uhlalutyo ngokomxholo lwathi lwasetyenziswa ukuhlalutya ulwazi olwabhalwayo luvela kudliwano-ndlebe olwashicilelwayo, idatha eyayisuka kubafundi yathi yahlalutywa ngokusebenzisa uhlalutyo ngokwenkcazelo nangokuthelekelela kunye neStatistical Pakage for Social Sciences (SPSS) njengesixhobo senkcukacha-manani kwaye uhlalutyo loxwebhu lwathi lwasetyenziswa ukuhlalutya imigaqo-nkqubo yolwimi. Iziphumo zibonakalisa ukuba iiyunivesithi zizibophelele ekufikelelekeni kwabafundi kumaziko emfundo ephakamileyo. Impumelelo yabafundi ithi ithityazwe kukusetyenziswa kolwimi olunye apho uninzi lweeyunivesithi zisebenzisa isiNgesi kuphela njengolwimi lokufunda nokufundisa. Ukusetyenziswa kolwimi olunye kuthi kuchaphazela gwenxa impumelelo yabafundi nokuqhuba ngcono ezifundweni. Iziphumo zibonakalisa ukuba kukho imfuno emmandla kubafundi yokuba izixhobo zokufunda nokufundisa zifumaneke nangeelwimi zesiNtu. Inyathelo elihle lelokuba zonke iiyunivesithi ezichongiweyo zinayo imigaqo-nkqubo yolwimi kodwa imigaqo-nkqubo yolwimi emininzi midala kuba ifanelwe ukuba iphononongwe emva kweminyaka emihlanu ubuncinane. Iziphumo zibonakalisa ukuba iiyunivesithi azinazo izicwangciso zokusetyenziswa kwemigaqo-nkqubo yolwimi. Ukungabikho kwesicwangciso sokusetyenziswa komgaqo-nkqubo wolwimi kuchaphazela gwenxa ukusetyenziswa kwawo. Olu phando lundulula ukuba iiyunivesithi zifanele ukuba zibonelele ngezixhobo zokufunda nokufundisa ezingeelwimi zesiNtu ukukhawulelana neemfuno zabafundi. Ukwandisa impumelelo, abafundi kufanele ukuba bavavanywe ngalo naluphi na ulwimi olusemthethweni lweyunivesithi. Izicwangciso zokusetyenziswa komgaqo-nkqubo wolwimi zifanele ukuba ziveliswe njengenyewe engxamisekileyo ukuze kuphuculwe ukusetyenziswa kwemigaqo- nkqubo yolwimi kwiiyunivesithi.
- Full Text:
- Date Issued: 2018
A framework for designing ambient assisted living services for disabled individuals
- Authors: Kyazze, Michael
- Date: 2018
- Subjects: Assistive computer technology , Computers and people with disabilities Self-help devices for people with disabilities People with disabilities -- Means of communication -- Technological innovations Communication devices for people with disabilities
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/31240 , vital:31347
- Description: Physically disabled individuals face a number of challenges when carrying out their everyday activities such as moving around, communicating with others, and their personal care. One way of overcoming these challenges is by using personal assistants. An alternative is to enable independence through assistive technology. This research aimed to investigate how physically disabled individuals experience these challenges, and how assistive technology can enable them to be more independent. In order to achieve the goal of this research, existing literature was reviewed on disability, assisted living, and interaction techniques. The literature study on disability identified some of the challenges faced by disabled individuals in their daily lives. In order to contextualize these challenges, interview studies with eighteen disabled individuals, and twelve personal assistants were carried out in Kampala, Uganda and Port Elizabeth, South Africa. The participants from both Uganda and South Africa were limited to those living in urban areas. The Ugandan participants noted that, whereas technology may assist their daily lives, their most essential needs are basic disability support aids such as wheelchairs and better long canes. This was in contrast with the South African participants, who have access to basic disability support aids. The South African participants identified their key needs as controlling an electronic environment without assistance, e.g. house lights, using a mobile phone, and using a computer without assistance. The interviews narrowed down the scope to focus on individuals with quadriplegia, specifically individuals who have limited hand use, but can comfortably speak and move their heads, and make gestures such as head shake and nod. Literature on assisted living technologies and frameworks, provided the technical foundation for the research. The literature review of interaction techniques identified a number of possible ways in which individuals with quadriplegia can interact with technology. An appropriate set of interaction techniques, namely head shake and nod, voice, and facial feature tracking were identified. Evaluations of the interaction techniques excluded head shake and nod, because of an inconsistency in detecting an individual’s head pose in different lighting conditions, when using a Microsoft Kinect. Voice and facial feature tracking using a standard computer camera were identified as the most suitable interaction techniques for this study. A framework for designing assisted living software services was developed. The framework allows disability researchers and solution developers to understand the needs of a given disability group, and design relevant solutions. To demonstrate that the proposed framework iii | P a g e addresses the main aim of this research, a prototype was developed that enables users to control smart lights (Phillips hue), a Smart TV (Samsung), and carry out basic navigation and webbrowsing on a computer. Users could interact with the software using voice and facial feature commands. A usability study was carried out with fifteen physically disabled individuals in Port Elizabeth, South Africa. The results of the evaluation study were highly positive. The successful evaluation of the prototype provided empirical evidence that the proposed framework does assist in the design of relevant and useful software services, to meet the unique needs of physically disabled individuals.
- Full Text:
- Date Issued: 2018
- Authors: Kyazze, Michael
- Date: 2018
- Subjects: Assistive computer technology , Computers and people with disabilities Self-help devices for people with disabilities People with disabilities -- Means of communication -- Technological innovations Communication devices for people with disabilities
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/31240 , vital:31347
- Description: Physically disabled individuals face a number of challenges when carrying out their everyday activities such as moving around, communicating with others, and their personal care. One way of overcoming these challenges is by using personal assistants. An alternative is to enable independence through assistive technology. This research aimed to investigate how physically disabled individuals experience these challenges, and how assistive technology can enable them to be more independent. In order to achieve the goal of this research, existing literature was reviewed on disability, assisted living, and interaction techniques. The literature study on disability identified some of the challenges faced by disabled individuals in their daily lives. In order to contextualize these challenges, interview studies with eighteen disabled individuals, and twelve personal assistants were carried out in Kampala, Uganda and Port Elizabeth, South Africa. The participants from both Uganda and South Africa were limited to those living in urban areas. The Ugandan participants noted that, whereas technology may assist their daily lives, their most essential needs are basic disability support aids such as wheelchairs and better long canes. This was in contrast with the South African participants, who have access to basic disability support aids. The South African participants identified their key needs as controlling an electronic environment without assistance, e.g. house lights, using a mobile phone, and using a computer without assistance. The interviews narrowed down the scope to focus on individuals with quadriplegia, specifically individuals who have limited hand use, but can comfortably speak and move their heads, and make gestures such as head shake and nod. Literature on assisted living technologies and frameworks, provided the technical foundation for the research. The literature review of interaction techniques identified a number of possible ways in which individuals with quadriplegia can interact with technology. An appropriate set of interaction techniques, namely head shake and nod, voice, and facial feature tracking were identified. Evaluations of the interaction techniques excluded head shake and nod, because of an inconsistency in detecting an individual’s head pose in different lighting conditions, when using a Microsoft Kinect. Voice and facial feature tracking using a standard computer camera were identified as the most suitable interaction techniques for this study. A framework for designing assisted living software services was developed. The framework allows disability researchers and solution developers to understand the needs of a given disability group, and design relevant solutions. To demonstrate that the proposed framework iii | P a g e addresses the main aim of this research, a prototype was developed that enables users to control smart lights (Phillips hue), a Smart TV (Samsung), and carry out basic navigation and webbrowsing on a computer. Users could interact with the software using voice and facial feature commands. A usability study was carried out with fifteen physically disabled individuals in Port Elizabeth, South Africa. The results of the evaluation study were highly positive. The successful evaluation of the prototype provided empirical evidence that the proposed framework does assist in the design of relevant and useful software services, to meet the unique needs of physically disabled individuals.
- Full Text:
- Date Issued: 2018
A psychobiographical study of Temple Grandin
- Authors: Wannenburg, Nicola
- Date: 2018
- Subjects: Grandin, Temple , Psychology Biographical methods , Psychoanalysis , Autistic women United States Biography , Women animal specialists United States Biography , Developmental psychology , Erikson, Erik H (Erik Homburger), 1902-1994
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/57358 , vital:26877
- Description: Psychobiographical researchers methodically formulate life histories and interpret them by means of psychological theories. The research typically focuses on exemplary and completed lives. The cases that are studied are usually of individuals who are of particular interest to society as a result of excelling in their particular fields, be they to benefit or detriment of society. Temple Grandin was chosen for this study using purposive sampling as she meets the psychobiographical requirement of being an extraordinary individual. As an individual with autism Grandin faced many challenges growing up. Despite a difficult and absent beginning, Grandin developed into a stable and scientifically creative adult who contributes to society. She excels as an animal scientist and designer of humane livestock handling facilities and has an international reputation for her contribution to the livestock industry and animal welfare. The primary aim of this study is to describe and interpret the life of Temple Grandin through Erikson’s (1950/1973) theory of psychosocial development. A mixed method approach (Yin, 2006) was employed for the conduction of this study. The overarching data processing and analysis guidelines for this study were provided by Miles and Huberman (1994, 2002a, 2002b). The conduction of the processing and analysis of data was aided by Alexander’s (1988, 1990) method of asking the data questions as well as an integration of Yin’s (2014) time series analysis with Erikson’s (1950/1973) triple bookkeeping approach. This study contributes to the development of psychobiographical research in South Africa as well as to personality and developmental theory.
- Full Text:
- Date Issued: 2018
- Authors: Wannenburg, Nicola
- Date: 2018
- Subjects: Grandin, Temple , Psychology Biographical methods , Psychoanalysis , Autistic women United States Biography , Women animal specialists United States Biography , Developmental psychology , Erikson, Erik H (Erik Homburger), 1902-1994
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/57358 , vital:26877
- Description: Psychobiographical researchers methodically formulate life histories and interpret them by means of psychological theories. The research typically focuses on exemplary and completed lives. The cases that are studied are usually of individuals who are of particular interest to society as a result of excelling in their particular fields, be they to benefit or detriment of society. Temple Grandin was chosen for this study using purposive sampling as she meets the psychobiographical requirement of being an extraordinary individual. As an individual with autism Grandin faced many challenges growing up. Despite a difficult and absent beginning, Grandin developed into a stable and scientifically creative adult who contributes to society. She excels as an animal scientist and designer of humane livestock handling facilities and has an international reputation for her contribution to the livestock industry and animal welfare. The primary aim of this study is to describe and interpret the life of Temple Grandin through Erikson’s (1950/1973) theory of psychosocial development. A mixed method approach (Yin, 2006) was employed for the conduction of this study. The overarching data processing and analysis guidelines for this study were provided by Miles and Huberman (1994, 2002a, 2002b). The conduction of the processing and analysis of data was aided by Alexander’s (1988, 1990) method of asking the data questions as well as an integration of Yin’s (2014) time series analysis with Erikson’s (1950/1973) triple bookkeeping approach. This study contributes to the development of psychobiographical research in South Africa as well as to personality and developmental theory.
- Full Text:
- Date Issued: 2018
A review of Climate-Smart system innovations in two Agricultural Colleges in the North West Province of South Africa
- Authors: Van Staden, Wilma
- Date: 2018
- Subjects: Crops and climate South Africa North-West , Sustainable agriculture South Africa North-West , Agriculture Environmental aspects South Africa North-West , Agricultural colleges Curricula South Africa , Agricultural innovations , Agricultural ecology South Africa North-West
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/63426 , vital:28410
- Description: This study was centred on the Agricultural Innovation System in the North West Province, South Africa as a response to climate change. The study developed during a time when Climate-Smart Agriculture emerged in policy and was developed as a strategic agricultural innovation process in response to changes in climate that increased food insecurity. The Agricultural Colleges embedded in the agricultural system realised that they were teaching students without a clear provision for climate change and therefore needed to initiate climate responsive innovations to comply with the Climate-Smart strategy that had been proposed by the provincial authorities. This provided the context for the study to track and support the innovation process of transitioning towards Climate-Smart responsive curriculum and learning practices within the system. A theoretical framework for the study was developed using a Cultural Historical Activity Theory perspective. This allowed the researcher to approach the research process as two case studies of innovation within the Agricultural Innovation System of the North West Province. The study developed as an iterative process of innovation support and tracking. At the early stages of the research process, data were generated through document analysis and a survey completed by the research participants at the preliminary consultative workshop. The contextual data allowed the researcher to begin to develop a clear contextual profile for both case studies. The consultative workshops were held to orientate the research around the central problems and challenges related to curriculum alignment with provincial Climate-Smart Agricultural policies. The methodology thereafter was developed as an iterative process of successive intervention-innovation workshops where the participating staff in each college reviewed their curriculum with the support of a Climate-Smart Innovation Tool. This tool was developed as a mediating resource for participants to undertake intervention work towards curriculum innovation in their context. The historical analysis from the two consultative workshops and the data derived from the initial use of the Climate-Smart Innovation Tool was used to model the activity systems in the respective colleges and the provincial system. This analysis enabled the researcher to scope how the system was currently functioning and how it had changed over time. During the workshops, curriculum innovations were reviewed and a fuller picture of the challenges of system innovation emerged, especially from a curriculum innovation vantage point. This system analysis was used to analyse emergent tensions and contradictions within the system and to build a picture of the complexities of participating staff initiating innovations towards Climate-Smart responsiveness in the colleges and within the Agricultural Innovation System. During the review and tracking of the supported innovation process the Climate-Smart Innovation Tool was developed into online sub-tools where either Departments or individual lecturers could review and track their own Climate-Smart responsiveness. The tool was shown to be a useful tool for surfacing contradictions, and identifying absences, and thus for charting out the start of reflexive learning and change processes needed for introducing climate responsive knowledge into the system. The study reveals that catalysing of curriculum and learning system innovation aligned with wider innovations in the agricultural innovation system requires specific tools, time and the understanding of the importance of micro-level innovation. The innovations within the system revealed the significance of allowing for time and processes that facilitate ‘ascending’ from the abstract concept of Climate-Smart Agriculture into more concrete curriculum processes. The curriculum review tool developed for this study served as an important double stimulation tool, along with activity system mapping, and ongoing refinement and clarification of the object of Climate-Smart Agriculture and associated contradictions and action plans for climate smart responsiveness in the college context. The tools and processes that were developed during this study, assisting in the emergence of micro-level innovation of the curriculum and learning system. The barriers and processes hampering curriculum and learning innovation within the system were identified. The study concludes with the recommendations on how a Climate-Smart innovation process might best be supported with reflexive tools within a curriculum and learning system during a time of institutional flux.
- Full Text:
- Date Issued: 2018
- Authors: Van Staden, Wilma
- Date: 2018
- Subjects: Crops and climate South Africa North-West , Sustainable agriculture South Africa North-West , Agriculture Environmental aspects South Africa North-West , Agricultural colleges Curricula South Africa , Agricultural innovations , Agricultural ecology South Africa North-West
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/63426 , vital:28410
- Description: This study was centred on the Agricultural Innovation System in the North West Province, South Africa as a response to climate change. The study developed during a time when Climate-Smart Agriculture emerged in policy and was developed as a strategic agricultural innovation process in response to changes in climate that increased food insecurity. The Agricultural Colleges embedded in the agricultural system realised that they were teaching students without a clear provision for climate change and therefore needed to initiate climate responsive innovations to comply with the Climate-Smart strategy that had been proposed by the provincial authorities. This provided the context for the study to track and support the innovation process of transitioning towards Climate-Smart responsive curriculum and learning practices within the system. A theoretical framework for the study was developed using a Cultural Historical Activity Theory perspective. This allowed the researcher to approach the research process as two case studies of innovation within the Agricultural Innovation System of the North West Province. The study developed as an iterative process of innovation support and tracking. At the early stages of the research process, data were generated through document analysis and a survey completed by the research participants at the preliminary consultative workshop. The contextual data allowed the researcher to begin to develop a clear contextual profile for both case studies. The consultative workshops were held to orientate the research around the central problems and challenges related to curriculum alignment with provincial Climate-Smart Agricultural policies. The methodology thereafter was developed as an iterative process of successive intervention-innovation workshops where the participating staff in each college reviewed their curriculum with the support of a Climate-Smart Innovation Tool. This tool was developed as a mediating resource for participants to undertake intervention work towards curriculum innovation in their context. The historical analysis from the two consultative workshops and the data derived from the initial use of the Climate-Smart Innovation Tool was used to model the activity systems in the respective colleges and the provincial system. This analysis enabled the researcher to scope how the system was currently functioning and how it had changed over time. During the workshops, curriculum innovations were reviewed and a fuller picture of the challenges of system innovation emerged, especially from a curriculum innovation vantage point. This system analysis was used to analyse emergent tensions and contradictions within the system and to build a picture of the complexities of participating staff initiating innovations towards Climate-Smart responsiveness in the colleges and within the Agricultural Innovation System. During the review and tracking of the supported innovation process the Climate-Smart Innovation Tool was developed into online sub-tools where either Departments or individual lecturers could review and track their own Climate-Smart responsiveness. The tool was shown to be a useful tool for surfacing contradictions, and identifying absences, and thus for charting out the start of reflexive learning and change processes needed for introducing climate responsive knowledge into the system. The study reveals that catalysing of curriculum and learning system innovation aligned with wider innovations in the agricultural innovation system requires specific tools, time and the understanding of the importance of micro-level innovation. The innovations within the system revealed the significance of allowing for time and processes that facilitate ‘ascending’ from the abstract concept of Climate-Smart Agriculture into more concrete curriculum processes. The curriculum review tool developed for this study served as an important double stimulation tool, along with activity system mapping, and ongoing refinement and clarification of the object of Climate-Smart Agriculture and associated contradictions and action plans for climate smart responsiveness in the college context. The tools and processes that were developed during this study, assisting in the emergence of micro-level innovation of the curriculum and learning system. The barriers and processes hampering curriculum and learning innovation within the system were identified. The study concludes with the recommendations on how a Climate-Smart innovation process might best be supported with reflexive tools within a curriculum and learning system during a time of institutional flux.
- Full Text:
- Date Issued: 2018
A social realist study of employability development in engineering education
- Authors: Nudelman, Gabrielle Reeve
- Date: 2018
- Subjects: Critical realism , Electrical engineering -- Study and teaching (Higher) -- South Africa -- Cape Town , Employability , Career education -- South Africa -- Cape Town , School-to-work transition -- South Africa -- Cape Town
- Language: English
- Type: thesis , text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62884 , vital:28307
- Description: This qualitative case study of a course pairing offered to final-year electrical engineering students at the University of Cape Town in 2015 was undertaken in order to better understand the ways in which participation in undergraduate courses can prepare engineering students for the workplace. The course pairing consisted of New Venture Planning and Professional Communication Studies. While the former aimed to expose students to the knowledge relating to starting a new business, the latter focused on teaching students how to create written and oral texts to support such an endeavour. Using Roy Bhaskar’s critical realism as a theoretical underlabourer, the study develops understandings regarding the generative mechanisms at work during the two courses. In support of this, the study posits an understanding of employability that moves beyond the acquisition of discrete workplace skills. Rather, employability is conceptualised as discursive transformation, with students being deemed “work-ready” when they develop discursive identities as engineers. Data generation took place by means of focus group and individual interviews, ethnographic observation and documentary research. Margaret Archer’s social realist tools – in particular, analytical dualism and the morphogenetic framework were used to trace the students’ transformations over the course pairing. It was argued that those students who developed discursive identities of engineers were those who, in Archer’s terms, emerged as social actors at the end of the course pairing. Two characteristics of the courses were found to enable this transformation: those parts that promoted deepened understanding of what the role of “engineer” entailed and the parts that provided spaces for students to develop their own personal identities. The findings of the study indicated that discursive identities as engineers were more likely to be developed through the group work and spaces for reflection engendered by the courses than as a result of the formal curriculum. The implications of the research are that, while a focus on employability in engineering education is valid and productive, this needs to be supported by opportunities for authentic learning experiences which afford students the opportunity to engage in learning that promotes real-life application of knowledge. , Thesis (PhD)--Rhodes University, Faculty of Education, Education, 2018
- Full Text:
- Date Issued: 2018
- Authors: Nudelman, Gabrielle Reeve
- Date: 2018
- Subjects: Critical realism , Electrical engineering -- Study and teaching (Higher) -- South Africa -- Cape Town , Employability , Career education -- South Africa -- Cape Town , School-to-work transition -- South Africa -- Cape Town
- Language: English
- Type: thesis , text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62884 , vital:28307
- Description: This qualitative case study of a course pairing offered to final-year electrical engineering students at the University of Cape Town in 2015 was undertaken in order to better understand the ways in which participation in undergraduate courses can prepare engineering students for the workplace. The course pairing consisted of New Venture Planning and Professional Communication Studies. While the former aimed to expose students to the knowledge relating to starting a new business, the latter focused on teaching students how to create written and oral texts to support such an endeavour. Using Roy Bhaskar’s critical realism as a theoretical underlabourer, the study develops understandings regarding the generative mechanisms at work during the two courses. In support of this, the study posits an understanding of employability that moves beyond the acquisition of discrete workplace skills. Rather, employability is conceptualised as discursive transformation, with students being deemed “work-ready” when they develop discursive identities as engineers. Data generation took place by means of focus group and individual interviews, ethnographic observation and documentary research. Margaret Archer’s social realist tools – in particular, analytical dualism and the morphogenetic framework were used to trace the students’ transformations over the course pairing. It was argued that those students who developed discursive identities of engineers were those who, in Archer’s terms, emerged as social actors at the end of the course pairing. Two characteristics of the courses were found to enable this transformation: those parts that promoted deepened understanding of what the role of “engineer” entailed and the parts that provided spaces for students to develop their own personal identities. The findings of the study indicated that discursive identities as engineers were more likely to be developed through the group work and spaces for reflection engendered by the courses than as a result of the formal curriculum. The implications of the research are that, while a focus on employability in engineering education is valid and productive, this needs to be supported by opportunities for authentic learning experiences which afford students the opportunity to engage in learning that promotes real-life application of knowledge. , Thesis (PhD)--Rhodes University, Faculty of Education, Education, 2018
- Full Text:
- Date Issued: 2018
Active learning strategies used by teachers during English reading comprehension lessons in six selected primary schools in Nigeria
- Adepoju, Adetokunboh Abayomi
- Authors: Adepoju, Adetokunboh Abayomi
- Date: 2018
- Subjects: Education, Primary -- Nigeria Learning strategies -- Nigeria
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8485 , vital:32838
- Description: Reading is an integral part of education from which one gets access to information. Unfortunately, reading ability among primary school pupils, the foundation level of education, is at its lowest ebb. These pupils when they get to secondary schools eventually fail external examinations-a situation which according to National Examination Council, is caused by inappropriate teaching methods. Consequent upon this, this study assessed active learning strategies used by teacher during English reading comprehension lessons in six selected primary schools in Nigeria. The main research question was: How do teachers employ active learning strategies in teaching English reading comprehension? The study adopted qualitative approach and case study design. With the use of purposive sampling technique to select six head teachers, six primary VI teachers, two members of the School Basic Committee, the Director Local Government Education Authority and six focus groups. The study used interviews, documents and focus group interview as research instruments to collect data. Data were analysed based on interpretivism paradigm which interpreted participants’ views according to the word view of the participants. The study found out that teachers have good knowledge of active learning strategies and use them in teaching English reading comprehension lessons but are faced with some daunting challenges such as non-availability of instructional materials, lack of library, lack of qualified teachers and lack of time. The study concluded that students fail woefully in English reading comprehension because teachers do not use appropriate teaching techniques. The study recommend that teachers must use active learning strategies effectively and more often during English reading comprehension, more time should be allocated for English reading comprehension, effective use of instructional materials should be considered and the government should employ specialist teachers to teach English reading comprehension.
- Full Text:
- Date Issued: 2018
- Authors: Adepoju, Adetokunboh Abayomi
- Date: 2018
- Subjects: Education, Primary -- Nigeria Learning strategies -- Nigeria
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8485 , vital:32838
- Description: Reading is an integral part of education from which one gets access to information. Unfortunately, reading ability among primary school pupils, the foundation level of education, is at its lowest ebb. These pupils when they get to secondary schools eventually fail external examinations-a situation which according to National Examination Council, is caused by inappropriate teaching methods. Consequent upon this, this study assessed active learning strategies used by teacher during English reading comprehension lessons in six selected primary schools in Nigeria. The main research question was: How do teachers employ active learning strategies in teaching English reading comprehension? The study adopted qualitative approach and case study design. With the use of purposive sampling technique to select six head teachers, six primary VI teachers, two members of the School Basic Committee, the Director Local Government Education Authority and six focus groups. The study used interviews, documents and focus group interview as research instruments to collect data. Data were analysed based on interpretivism paradigm which interpreted participants’ views according to the word view of the participants. The study found out that teachers have good knowledge of active learning strategies and use them in teaching English reading comprehension lessons but are faced with some daunting challenges such as non-availability of instructional materials, lack of library, lack of qualified teachers and lack of time. The study concluded that students fail woefully in English reading comprehension because teachers do not use appropriate teaching techniques. The study recommend that teachers must use active learning strategies effectively and more often during English reading comprehension, more time should be allocated for English reading comprehension, effective use of instructional materials should be considered and the government should employ specialist teachers to teach English reading comprehension.
- Full Text:
- Date Issued: 2018
Advanced high speed data and clock transmission over optical fibre for square kilometre telescope array
- Authors: Isoe, George Mosoti
- Date: 2018
- Subjects: Very large array telescopes -- South Africa , Semiconductor lasers Optical communications Optical amplifiers
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/30375 , vital:30935
- Description: There is an ever present need from Internet users for more bandwidth. This is manifested by continuous increase in bandwidth demanding applications such as 5G wireless, new end user consumer links like thunderbolt, video conferencing, high definition video-on-demand transmitted over the Internet and massive data transfers required with and within data centres for backup, storage and data processing in cloud computing. Fibre optic communications technologies are playing a pivotal role in communication, being a major enabling technology in our increasingly Internet-centric society. As network services continue to become more dynamic and diverse, Internet service providers are faced with a challenge of cost reduction in the transmission network, power and spectral efficiency as well as scalability of the optical network infrastructure to support incremental expansions and virtual machines. Intelligent design of terrestrial optical networks to allow for simultaneous signal transmission through shared network infrastructure, and the use of low cost, power efficient, high bandwidth transmitters such as vertical surface emitting lasers (VCSELs) as well as exploitation of spectral efficient in-complex advanced modulation formats is a viable approach to this situation. In this study, techniques for spectral efficiency upgrade and simultaneous transmission of data signal, reference frequency (RF) clock signal and pulse-per-second (PPS) over shared infrastructure have experimentally been optimized in a laboratory environment for adoption in next-generation telescope array networks such as the Square Kilometre Array (SKA), time keeping systems such as banking systems, Coordinated Universal Time(UTC) timing and Global Positioning Systems (GPS), as well as high capacity spectral efficient short reach optical fibre networks such as data centres. This work starts by experimentally optimizing VCSEL technology for simultaneous transmission of 10 Gbps data and 1.712 GHz RF clock signal over a single G. 655 optical fibre of length 24.75 Km at different channel spacing and different propagation direction for implementation in a cost effective next-generation telescope array network. The wavelength tuneability property of VCSEL transmitters allows for wavelength adjustment, a key requirement for simultaneous data and RF clock signal transmission over a single optical fibre. A receiver sensitivity of -19.19 dBm was experimentally achieved at back-to-back analysis. A 24.75 Km of simultaneous data and RF clock signal transmission performed at 0.4 nm channel spacing introduced a transmission penalty of 1.07 dB and 1.63 dB for counter and co-propagation scheme respectively. This work mainly utilized direct modulation and direct detection using a positive intrinsic negative (PIN) due to its simplicity and cost effectiveness. A novel modulation technique for simultaneous data and polarization-based pulse-per-second timing clock signal transmission using a single VCSEL carrier is experimentally demonstrated. Two signal types, a directly modulated 10 Gbps data signal and a polarization-based pulse per second (PPS) clock signal are modulated onto a single mode 10 GHz bandwidth VCSEL carrier at 1310 nm. Spectral efficiency is maximized by exploiting the inherent orthogonal polarization switching of the xiv VCSEL with changing bias in transmission of the PPS signal. A 10 Gbps VCSEL transmission with PPS over 11 Km of G.652 fibre introduced a transmission penalty of 0.52 dB. The contribution of PPS clock signal to this penalty was found to be 0.08 dB. A technique for simultaneous directly modulated data and phase modulated reference clock signal transmission over a signal channel in wavelength division multiplexing (WDM) solutions is experimentally demonstrated. This is to prepare solutions to the ever-increasing demand over gigabit/s, terabit/s and gigahertz capacities in WDM-based terrestrial optical fibre transmission systems such as telescope array networks. a total capacity of 30 Gbps (310 Gbps) data and 12 GHz ( 4 3 GHz) reference clock signal are multiplexed at a channel spacing of 100 GHz and simultaneously transmitted over a single mode G.655 fibre of length 24.73 Km. The recovery of the phase modulated RF clock signal using a differential delay line interferometry technique is experimentally demonstrated. A 625 Gbps (2525 Gbps) DWDM data transmission system is further implemented in simulation by multiplexing 25 channels at 25 Gbps per channel using 50 GHz channel spacing. A four level pulse amplitude modulation (4-PAM) data modulation format employing VCSELs is experimentally demonstrated for adoption in high bitrate networks such as big data science projects and data centre networks. 4-PAM offers a good trade-off between complexity, efficiency, reach, and sensitivity. A software defined digital signal processing (DSP) receiver is designed and implemented in MATLAB to recover the transmitted 4-PAM data signal cost effectively without the necessity of costly receiver hardware. A novel technique for maximizing carrier spectral efficiency through simultaneous 20 Gbps 4-PAM data and phase modulated 2 GHz RF clock signal transmission on a single mode 10 GHz bandwidth VCSEL carrier at 1310 nm is experimentally demonstrated for the first time to the best of our knowledge. Data transmission and clock stability performance of the designed high spectral efficient VCSEL-based link network is evaluated through BER curve plots, phase noise measurements and Allan variance analysis respectively. VCSEL-based Raman amplification is experimentally demonstrated as a viable approach for RF clock signal distribution in extended reach astronomical telescope array networks and other extended reach terrestrial optical fibre network application. This is achieved by adopting two pumping techniques namely forward pumping and backward pumping. A maximum on off gain of 5.7 dB and 1.5 dB was experimentally attained for forward pumping and backward pumping at 24 dBm pump power respectively, while a maximum 100.8 Km fibre transmission achieved experimentally. In summary, this study has successfully demonstrated in-complex, spectral efficient, low cost and power efficient simultaneous data signal, reference frequency (RF) clock signal and pulse-per-second (PPS) transmission techniques over shared network infrastructure. Simultaneous transmission of data, RF clock and PPS timing signal is relevant in nextgeneration telescope array networks such as the Square Kilometre Array (SKA), time keeping systems such as banking systems, Coordinated Universal Time (UTC) timing and Global Positioning Systems (GPS), as well as high capacity spectral efficient short reach optical fibre networks such as data centres.
- Full Text:
- Date Issued: 2018
- Authors: Isoe, George Mosoti
- Date: 2018
- Subjects: Very large array telescopes -- South Africa , Semiconductor lasers Optical communications Optical amplifiers
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/30375 , vital:30935
- Description: There is an ever present need from Internet users for more bandwidth. This is manifested by continuous increase in bandwidth demanding applications such as 5G wireless, new end user consumer links like thunderbolt, video conferencing, high definition video-on-demand transmitted over the Internet and massive data transfers required with and within data centres for backup, storage and data processing in cloud computing. Fibre optic communications technologies are playing a pivotal role in communication, being a major enabling technology in our increasingly Internet-centric society. As network services continue to become more dynamic and diverse, Internet service providers are faced with a challenge of cost reduction in the transmission network, power and spectral efficiency as well as scalability of the optical network infrastructure to support incremental expansions and virtual machines. Intelligent design of terrestrial optical networks to allow for simultaneous signal transmission through shared network infrastructure, and the use of low cost, power efficient, high bandwidth transmitters such as vertical surface emitting lasers (VCSELs) as well as exploitation of spectral efficient in-complex advanced modulation formats is a viable approach to this situation. In this study, techniques for spectral efficiency upgrade and simultaneous transmission of data signal, reference frequency (RF) clock signal and pulse-per-second (PPS) over shared infrastructure have experimentally been optimized in a laboratory environment for adoption in next-generation telescope array networks such as the Square Kilometre Array (SKA), time keeping systems such as banking systems, Coordinated Universal Time(UTC) timing and Global Positioning Systems (GPS), as well as high capacity spectral efficient short reach optical fibre networks such as data centres. This work starts by experimentally optimizing VCSEL technology for simultaneous transmission of 10 Gbps data and 1.712 GHz RF clock signal over a single G. 655 optical fibre of length 24.75 Km at different channel spacing and different propagation direction for implementation in a cost effective next-generation telescope array network. The wavelength tuneability property of VCSEL transmitters allows for wavelength adjustment, a key requirement for simultaneous data and RF clock signal transmission over a single optical fibre. A receiver sensitivity of -19.19 dBm was experimentally achieved at back-to-back analysis. A 24.75 Km of simultaneous data and RF clock signal transmission performed at 0.4 nm channel spacing introduced a transmission penalty of 1.07 dB and 1.63 dB for counter and co-propagation scheme respectively. This work mainly utilized direct modulation and direct detection using a positive intrinsic negative (PIN) due to its simplicity and cost effectiveness. A novel modulation technique for simultaneous data and polarization-based pulse-per-second timing clock signal transmission using a single VCSEL carrier is experimentally demonstrated. Two signal types, a directly modulated 10 Gbps data signal and a polarization-based pulse per second (PPS) clock signal are modulated onto a single mode 10 GHz bandwidth VCSEL carrier at 1310 nm. Spectral efficiency is maximized by exploiting the inherent orthogonal polarization switching of the xiv VCSEL with changing bias in transmission of the PPS signal. A 10 Gbps VCSEL transmission with PPS over 11 Km of G.652 fibre introduced a transmission penalty of 0.52 dB. The contribution of PPS clock signal to this penalty was found to be 0.08 dB. A technique for simultaneous directly modulated data and phase modulated reference clock signal transmission over a signal channel in wavelength division multiplexing (WDM) solutions is experimentally demonstrated. This is to prepare solutions to the ever-increasing demand over gigabit/s, terabit/s and gigahertz capacities in WDM-based terrestrial optical fibre transmission systems such as telescope array networks. a total capacity of 30 Gbps (310 Gbps) data and 12 GHz ( 4 3 GHz) reference clock signal are multiplexed at a channel spacing of 100 GHz and simultaneously transmitted over a single mode G.655 fibre of length 24.73 Km. The recovery of the phase modulated RF clock signal using a differential delay line interferometry technique is experimentally demonstrated. A 625 Gbps (2525 Gbps) DWDM data transmission system is further implemented in simulation by multiplexing 25 channels at 25 Gbps per channel using 50 GHz channel spacing. A four level pulse amplitude modulation (4-PAM) data modulation format employing VCSELs is experimentally demonstrated for adoption in high bitrate networks such as big data science projects and data centre networks. 4-PAM offers a good trade-off between complexity, efficiency, reach, and sensitivity. A software defined digital signal processing (DSP) receiver is designed and implemented in MATLAB to recover the transmitted 4-PAM data signal cost effectively without the necessity of costly receiver hardware. A novel technique for maximizing carrier spectral efficiency through simultaneous 20 Gbps 4-PAM data and phase modulated 2 GHz RF clock signal transmission on a single mode 10 GHz bandwidth VCSEL carrier at 1310 nm is experimentally demonstrated for the first time to the best of our knowledge. Data transmission and clock stability performance of the designed high spectral efficient VCSEL-based link network is evaluated through BER curve plots, phase noise measurements and Allan variance analysis respectively. VCSEL-based Raman amplification is experimentally demonstrated as a viable approach for RF clock signal distribution in extended reach astronomical telescope array networks and other extended reach terrestrial optical fibre network application. This is achieved by adopting two pumping techniques namely forward pumping and backward pumping. A maximum on off gain of 5.7 dB and 1.5 dB was experimentally attained for forward pumping and backward pumping at 24 dBm pump power respectively, while a maximum 100.8 Km fibre transmission achieved experimentally. In summary, this study has successfully demonstrated in-complex, spectral efficient, low cost and power efficient simultaneous data signal, reference frequency (RF) clock signal and pulse-per-second (PPS) transmission techniques over shared network infrastructure. Simultaneous transmission of data, RF clock and PPS timing signal is relevant in nextgeneration telescope array networks such as the Square Kilometre Array (SKA), time keeping systems such as banking systems, Coordinated Universal Time (UTC) timing and Global Positioning Systems (GPS), as well as high capacity spectral efficient short reach optical fibre networks such as data centres.
- Full Text:
- Date Issued: 2018
Advanced radio interferometric simulation and data reduction techniques
- Authors: Makhathini, Sphesihle
- Date: 2018
- Subjects: Interferometry , Radio interferometers , Algorithms , Radio telescopes , Square Kilometre Array (Project) , Very Large Array (Observatory : N.M.) , Radio astronomy
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/57348 , vital:26875
- Description: This work shows how legacy and novel radio Interferometry software packages and algorithms can be combined to produce high-quality reductions from modern telescopes, as well as end-to-end simulations for upcoming instruments such as the Square Kilometre Array (SKA) and its pathfinders. We first use a MeqTrees based simulations framework to quantify how artefacts due to direction-dependent effects accumulate with time, and the consequences of this accumulation when observing the same field multiple times in order to reach the survey depth. Our simulations suggest that a survey like LADUMA (Looking at the Distant Universe with MeerKAT Array), which aims to achieve its survey depth of 16 µJy/beam in a 72 kHz at 1.42 GHz by observing the same field for 1000 hours, will be able to reach its target depth in the presence of these artefacts. We also present stimela, a system agnostic scripting framework for simulating, processing and imaging radio interferometric data. This framework is then used to write an end-to-end simulation pipeline in order to quantify the resolution and sensitivity of the SKA1-MID telescope (the first phase of the SKA mid-frequency telescope) as a function of frequency, as well as the scale-dependent sensitivity of the telescope. Finally, a stimela-based reduction pipeline is used to process data of the field around the source 3C147, taken by the Karl G. Jansky Very Large Array (VLA). The reconstructed image from this reduction has a typical 1a noise level of 2.87 µJy/beam, and consequently a dynamic range of 8x106:1, given the 22.58 Jy/beam flux Density of the source 3C147.
- Full Text:
- Date Issued: 2018
- Authors: Makhathini, Sphesihle
- Date: 2018
- Subjects: Interferometry , Radio interferometers , Algorithms , Radio telescopes , Square Kilometre Array (Project) , Very Large Array (Observatory : N.M.) , Radio astronomy
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/57348 , vital:26875
- Description: This work shows how legacy and novel radio Interferometry software packages and algorithms can be combined to produce high-quality reductions from modern telescopes, as well as end-to-end simulations for upcoming instruments such as the Square Kilometre Array (SKA) and its pathfinders. We first use a MeqTrees based simulations framework to quantify how artefacts due to direction-dependent effects accumulate with time, and the consequences of this accumulation when observing the same field multiple times in order to reach the survey depth. Our simulations suggest that a survey like LADUMA (Looking at the Distant Universe with MeerKAT Array), which aims to achieve its survey depth of 16 µJy/beam in a 72 kHz at 1.42 GHz by observing the same field for 1000 hours, will be able to reach its target depth in the presence of these artefacts. We also present stimela, a system agnostic scripting framework for simulating, processing and imaging radio interferometric data. This framework is then used to write an end-to-end simulation pipeline in order to quantify the resolution and sensitivity of the SKA1-MID telescope (the first phase of the SKA mid-frequency telescope) as a function of frequency, as well as the scale-dependent sensitivity of the telescope. Finally, a stimela-based reduction pipeline is used to process data of the field around the source 3C147, taken by the Karl G. Jansky Very Large Array (VLA). The reconstructed image from this reduction has a typical 1a noise level of 2.87 µJy/beam, and consequently a dynamic range of 8x106:1, given the 22.58 Jy/beam flux Density of the source 3C147.
- Full Text:
- Date Issued: 2018
An analysis of the implementation of the Teaching Development Grant in the South African Higher Education Sector
- Authors: Moyo, Mtheto Temwa
- Date: 2018
- Subjects: Education, Higher -- Aims and objectives -- South Africa , Government aid to higher education -- South Africa , Education, Higher -- South Africa -- Evaluation , Education, Higher -- Social aspects -- South Africa , Educational leadership -- South Africa , Educational equalization -- South Africa , Education, Higher -- Economic aspects -- South Africa , Teaching Development Grant (South Africa)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62225 , vital:28141
- Description: The South African government has attempted to address various transformation and efficiency challenges in the system through the steering mechanisms at its disposal. This study analyses the implementation of one of these mechanisms, the Teaching Development Grant (TDG), which is designed to enhance student learning through the improvement of teaching and teaching resources at South African universities. Since the inception as an earmarked grant ten years ago, a total of R5.5 billion has been allocated for the TDG. The study thus sought to answer the question: What are the factors enabling and constraining the use of the TDG to enhance teaching and student success at South African universities? A total of 275 TDG progress reports and budget plans were analysed alongside other TDG documentation such as TDG payment letters to universities and institutional submissions that universities made on the use of the TDG for the 2008 TDG Review. The TDG criteria and policy over the years were also included as data. The analysis used Archer’s (1995; 1996) morphogenesis/stasis framework, which is concerned with how change does or does not happen over time. Archer’s analytical dualism was used to identify the interplay of structural, cultural and agential mechanisms shaping the emergence of and practices associated with TDGs in order to make sense of the events and experiences in the data. One of the main findings of the study was that the historically-based differentiated nature of the South African higher education landscape constrained the implementation of the TDG. The stark resource differences in the sector has meant that the TDG has not fully translated into system-wide gains. In the initial years of TDG implementation from 2004 to 2013, most institutions did not use the TDG for teaching development initiatives per se, but rather spent the bulk of the funds on infrastructure and equipment. Such resource gaps have persisted and continue to compromise the academic enterprise at affected universities. The data also showed that universities which have access to additional funding other than state funding have been able to augment and advance their own funds and were thus able to at least partially counter late payments of the TDG, fluctuations in allocations, and the short-term nature of TDG budgets and inadequate allocations. This enabled relatively straightforward implementation of the teaching and learning enhancement programmes at these universities, while there were ongoing implementation difficulties at the universities with the lowest success rates, the very institutions the grant was most targeted to address. The study showed that the shortage of appropriate teaching and learning staff constrained the nature and type of interventions. Historically Disadvantaged Institutions in particular struggled to attract and retain the much-needed expertise. This emerged from multiple structural constraints such as geographical location, conditions of work, inefficient human resources systems, lack of access to financial resources for competitive packages, and instability in governance and management structures at some universities. Emerging from the data in the study is the fact that staffing challenges remain one of the core constraints in the implementation of the TDG. In particular, the data indicated that teaching and learning staff hired on the basis of TDG funds were generally hired as part-time or contract staff. This meant that their academic qualifications and experience in teaching development were limited and, in many cases, it meant that the posts were not filled at all. In some cases, the fluctuating budgets meant that some projects had to be downscaled or abandoned altogether. The study found that many of the interventions that were implemented had tenuous links to teaching and learning and, even where there were such links, these interventions were often based on fairly a-theoretical, common-sense understandings of what would develop teaching. In many universities, there was little evidence of institution-level planning of interventions aimed at fundamentally addressing the need for teaching development. The limited access to teaching and learning expertise across the sector was mirrored in the uneven distribution of expertise in administration, financial management, institutional planning and human resource divisions, which had implications for the establishment of monitoring systems and implementation processes of the TDG. The lack of strong systems and policies encouraged cultures that did not value transparency, accountability or compliance to the TDG policy. The role of corporate agency in the form of leadership and ownership of projects emerged as a key enabler in the implementation of the TDG. All of these structures shaped the ability of institutions to spend the TDG and in some cases millions of Rands in funds were not spent and so were withheld. The study found that the inability of some universities to spend was exacerbated by the problem of a lack of alignment between the DHET financial year and the academic year. Although the TDG has made a notable contribution to the advancement of teaching and learning (T&L) nationally, this study revealed that the blunt implementation of the TDG across the sector constrained the gains. In particular, the practice of withholding unspent funds focused only on the symptoms of underspending and not on the structural, cultural and agential mechanisms that led to such under-expenditure. The withheld funds were redirected by the government for national projects but as all universities including the well-resourced Historically Advantaged Institutions (HAIs) had access to these withheld funds this translated into a regressive distribution of the TDG. Limited capacity within DHET to direct, manage and monitor the grants has also had a constraining effect on their use and the secondment of a teaching and learning expert to the department was seen to be a significant but short-term enablement in this regard. The findings of how the TDG implementation has emerged in the South African higher education sector are particularly important at this point in time as the TDG together with the Research Development Grant will be reconfigured into a new grant called the University Capacity Development Grant as from 2018. This study provides significant insights into the structural, cultural, and agential enablements and constraints of this new grant being able to drive changes in the sector. The findings also provide insights into the implementation of other earmarked grants. , Boma la South Africa layesera kuthetsa mavuto omwe amadza posintha ndi kulongosola zinthu kudzera mu njira zosiyanasiyana. Kafukufukuyu akuunikira imodzi mwa njirazi yotchedwa Teaching Development Grant (TDG) yomwe inakonzedwa polimbikitsa maphunziro kudzera mukagwiritsidwe ntchito ka zipangizo zophunzitsira ndi zophunzirira za makono m’sukulu za ukachenjede ku South Africa. Ndalama zapafupifupi R5.5 billion ndi zomwe zaperekedwa kuti zigwiritsidwe nchito mu ndondomekoyi kuchokera pa nthawi yomwe inakhazikitsidwa; zaka khumi zapitazo. Kafukufukuyu anayesera kuyankha funso loti: Ndi zinthu ziti zomwe zimalimbikitsa kapena kubwezeretsa m’mbuyo kagwiritsidwe ntchito ka (TDG) polimbikitsa kuchita bwino kwa aphunzitsi ndi ophunzira m’sukulu za ukachenjede? Zikalata zosonyeza makhonzedwe a ophunzira, ndondomeko za kayendetseredwe ka chuma, zikalata za malipiridwe ndi zikalata zopezeka m’sukulu zaukachenjedezi zokhudzana ndi njira ya TDG zomwe zakhala zikugwiritsidwa ntchito zaka khumi zapitazi zinatengedwanso ngati uthenga wofunika koposa. Kauniuniyu anatsalira njira yotchedwa ‘Archer’s (1995/1996) Morphogenesis/Status Framework’ yomwe imafotokozera momwe kusintha kumachitikira pena kulepherekera. Njira younikira ya Archer: yothandizira pofufuza momwe kayendetsedwe ka bungwe, chikhalidwe komanso anthu oyendetsa bungwe amathandizira poonetsera momwe TDG imakhalira inagwiritsidwa ntchito poyesera kumvetsa zochitika komanso zopezeka mu kafukufukuyu. Chimodzi mwa zotsatira za kafukufukuyu n’chakuti kagwiritsidwe ntchito ka TDG kamabwezeredwa m’mbuyo ndi momwe sukulu za ukachenjede ku South Africa zidapangidwira. Kusiyana kwa usiwa wa zipangizo m’sukuluzi kudapangitsa kuti njira ya TDG isaonetse zipatso kwenikweni. Mu zaka zoyambirira itangokhazikidwitsa (2007 - 2013), sukulu zambiri sizidagwiritse ntchito TDG polimbikitsa kaphunzitsidwe. M’malo mwake ndalama zankhaninkhani zidagwiritsidwa ntchito pa zomangamanga ndi kugulira zipangizo. Usiwa wa zipangizowu ulipobe ndipo ukusokoneza mbali ya maphunziro m’sukulu zokhudzidwazi. Kafukufukuyu anasonyezanso kuti sukulu zomwe zimalandira thandizo lowonjezera pa lomwe zimalandira ku boma zakhala zikuyesetsa kuthana ndi vuto lopereka mochedwa ndalama za mundondomeko ya TDG ndi dongosolo la m’mene ndalamazi zigwirire ntchito. Izi zinawachititsa kuti asapeze mavuto ambiri polimbikitsa ndondomeko za kaphunzitsidwe ndi kaphunziridwe pomwe ena amavutika nazo. Enawa n’kukhala sukulu zomwe sizimachita bwino, zomwenso thandizoli lidalunjika pa izo kuti zithandizike. Kafukufukuyu anasonyeza kuti kuchepa kwa aphunzitsi kudapsinja zochitika zokhudza njirayi. Sukulu zosachita bwino kuchokera kalezi zidavutika kupeza ndi kusunga ogwira ntchito ake. Izi zimakhala choncho kaamba ka zifukwa zosiyanasiyana monga komwe sukuluyo ili, malamulo a ntchito, kupanda ukadaulo kwa oyang’anira antchitowa, kutalikirana ndi njira zina zopezera ndalama komanso kusakhazikika kwa anthu m’maudindo. Zina zotulukanso mu mfundo zotoledwazi zinaulula kuti vuto lina lalikulu linali ogwira ntchito. Polimbikitsa njira ya TDG, zimatanthauza kuti aphunzitsi omwe azilembedwa azikhala osakhazikika pa sukuluzi kapena a kontarakiti. Izi zimatanthauza kuti maphunziro ndi luntha lawo zimayenera kukhala zochepera. Mwanjira ina, tikhonza kunena kuti ogwira ntchitoyi panalibe. Nthawi zina, kusinthasintha kwa ndondomeko zachuma madongosolo ena kusiyidwa kapena kuchitika mosalongosoka. Kafukufukuyu anasonyezanso kuti zambiri mwa mfundo zomwe zinayikidwa kuti zigwiritsidwe ntchito zinali zosathandiza kwenikweni polimbikitsa maphunzirowa. Ndipo komwe mfundozi zinakhazikitsidwa, zinali chabe kufotokozera zinthu zodziwika kale ndi kale zokhudza zomwe zingalimbikitse uphunzitsi. M’sukulu zambiri za ukachenjede, pali umboni wochepa wa mfundo zomwe zinaikidwiratu ndi cholinga chopititsa patsogolo uphunzitsiwu. Kusowa kwa ukadaulo pa maphunzirowa kunaonekanso makamaka m’madera monga a oyendetsa sukuluzi, oyang’ana za chuma, olongosola malo onse komanso oyang’anira antchito. Panalibe kugawana anthuwa mofanana. Izi zidakhudza kwambiri kalondolondo ndinso kayendetsedwe ka TDG. Kusowa kwa ndondomeko zabwino ndi malamulo okhazikika kunalimbikitsa chikhalidwe cha chinyengo ndi kusatsatira mfundo za mundondomekoyi popereka utsogoleri ndi umwini ndiye unali wofunika polimbikitsa ndondomekoyi. Madongosolo otere anathandiza kuti sukulu zigwiritse ntchito njira ya TDG ndipo pena ndalama mamiliyoni zibwezedwe. Kafukufukuyu anaonetsa kuti kulephera kwa sukulu zina kugwiritsa ntchito ndalama kunachitika kaamba kosazindikira malire a chaka cha DHET ndi chaka cha maphunziro. Ngakhale njira ya TDG yathandizako kagwiritsidwe ntchito ka zipangizo zophunzitsira ndi zophunzirira, kafukufukuyu wasonyeza kuti mavuto omwe anaoneka mu ndondomeko ya TDG aphimba ubwino wake. Monga, m’chitidwe wobweza ndalama zosagwira ntchito unalunjika pa kulephera kugwiritsa ntchito ndalama zonse osati pa ubale pakati pa kayendetsedwe ka bungwe, chikhalidwe ndinso anthu oyendetsa bungwe. Ndalama zotsarazi zinalowetsedwa ku zitukuko zina ndi boma. Koma poti sukulu zonse za ukachenjede kuphatikizapo HAI zinapeza mwayi wa ndalamazi, izi zimabweretsa kulowa pansi kwa dongosolo la TDG. Kulephera mu DHET kutsogolera, kuyendetsa ndi kulondoloza thandizo kwadzetsanso mavuto pa kagwiritsidwe ntchito kake ngakhalenso kutumizidwa kwa katswiri pa kaphunzitsidwe kunaoneka ngati kofunika kosathandiza kwenikweni chifukwa kudali kwa nthawi yochepa. Zotsatira za kafukufukuyu (zokhudza maphunziro a ukachenjede ku South Africa) ndi zofunika kwambiri makamaka nthawi ino pomwe TDG pamodzi ndi RDG (Research Development Grant) zikhale kuunikiridwanso ndi kupanga thandizo latsopano lotchedwa University Capacity Development Grant kuyambira m’chaka cha 2018. Kafukufukuyu waunika mozama kayendetsedwe, chikhalidwe komanso oyendetsa zithandizo komanso mavuto kuti thandizo latsopanoli likathe kubweretsa kusintha. Zotsatirazi zaunikiranso kayendetsedwe ka zithandizo zina zomwe zikufuna kuchitika.
- Full Text:
- Date Issued: 2018
- Authors: Moyo, Mtheto Temwa
- Date: 2018
- Subjects: Education, Higher -- Aims and objectives -- South Africa , Government aid to higher education -- South Africa , Education, Higher -- South Africa -- Evaluation , Education, Higher -- Social aspects -- South Africa , Educational leadership -- South Africa , Educational equalization -- South Africa , Education, Higher -- Economic aspects -- South Africa , Teaching Development Grant (South Africa)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62225 , vital:28141
- Description: The South African government has attempted to address various transformation and efficiency challenges in the system through the steering mechanisms at its disposal. This study analyses the implementation of one of these mechanisms, the Teaching Development Grant (TDG), which is designed to enhance student learning through the improvement of teaching and teaching resources at South African universities. Since the inception as an earmarked grant ten years ago, a total of R5.5 billion has been allocated for the TDG. The study thus sought to answer the question: What are the factors enabling and constraining the use of the TDG to enhance teaching and student success at South African universities? A total of 275 TDG progress reports and budget plans were analysed alongside other TDG documentation such as TDG payment letters to universities and institutional submissions that universities made on the use of the TDG for the 2008 TDG Review. The TDG criteria and policy over the years were also included as data. The analysis used Archer’s (1995; 1996) morphogenesis/stasis framework, which is concerned with how change does or does not happen over time. Archer’s analytical dualism was used to identify the interplay of structural, cultural and agential mechanisms shaping the emergence of and practices associated with TDGs in order to make sense of the events and experiences in the data. One of the main findings of the study was that the historically-based differentiated nature of the South African higher education landscape constrained the implementation of the TDG. The stark resource differences in the sector has meant that the TDG has not fully translated into system-wide gains. In the initial years of TDG implementation from 2004 to 2013, most institutions did not use the TDG for teaching development initiatives per se, but rather spent the bulk of the funds on infrastructure and equipment. Such resource gaps have persisted and continue to compromise the academic enterprise at affected universities. The data also showed that universities which have access to additional funding other than state funding have been able to augment and advance their own funds and were thus able to at least partially counter late payments of the TDG, fluctuations in allocations, and the short-term nature of TDG budgets and inadequate allocations. This enabled relatively straightforward implementation of the teaching and learning enhancement programmes at these universities, while there were ongoing implementation difficulties at the universities with the lowest success rates, the very institutions the grant was most targeted to address. The study showed that the shortage of appropriate teaching and learning staff constrained the nature and type of interventions. Historically Disadvantaged Institutions in particular struggled to attract and retain the much-needed expertise. This emerged from multiple structural constraints such as geographical location, conditions of work, inefficient human resources systems, lack of access to financial resources for competitive packages, and instability in governance and management structures at some universities. Emerging from the data in the study is the fact that staffing challenges remain one of the core constraints in the implementation of the TDG. In particular, the data indicated that teaching and learning staff hired on the basis of TDG funds were generally hired as part-time or contract staff. This meant that their academic qualifications and experience in teaching development were limited and, in many cases, it meant that the posts were not filled at all. In some cases, the fluctuating budgets meant that some projects had to be downscaled or abandoned altogether. The study found that many of the interventions that were implemented had tenuous links to teaching and learning and, even where there were such links, these interventions were often based on fairly a-theoretical, common-sense understandings of what would develop teaching. In many universities, there was little evidence of institution-level planning of interventions aimed at fundamentally addressing the need for teaching development. The limited access to teaching and learning expertise across the sector was mirrored in the uneven distribution of expertise in administration, financial management, institutional planning and human resource divisions, which had implications for the establishment of monitoring systems and implementation processes of the TDG. The lack of strong systems and policies encouraged cultures that did not value transparency, accountability or compliance to the TDG policy. The role of corporate agency in the form of leadership and ownership of projects emerged as a key enabler in the implementation of the TDG. All of these structures shaped the ability of institutions to spend the TDG and in some cases millions of Rands in funds were not spent and so were withheld. The study found that the inability of some universities to spend was exacerbated by the problem of a lack of alignment between the DHET financial year and the academic year. Although the TDG has made a notable contribution to the advancement of teaching and learning (T&L) nationally, this study revealed that the blunt implementation of the TDG across the sector constrained the gains. In particular, the practice of withholding unspent funds focused only on the symptoms of underspending and not on the structural, cultural and agential mechanisms that led to such under-expenditure. The withheld funds were redirected by the government for national projects but as all universities including the well-resourced Historically Advantaged Institutions (HAIs) had access to these withheld funds this translated into a regressive distribution of the TDG. Limited capacity within DHET to direct, manage and monitor the grants has also had a constraining effect on their use and the secondment of a teaching and learning expert to the department was seen to be a significant but short-term enablement in this regard. The findings of how the TDG implementation has emerged in the South African higher education sector are particularly important at this point in time as the TDG together with the Research Development Grant will be reconfigured into a new grant called the University Capacity Development Grant as from 2018. This study provides significant insights into the structural, cultural, and agential enablements and constraints of this new grant being able to drive changes in the sector. The findings also provide insights into the implementation of other earmarked grants. , Boma la South Africa layesera kuthetsa mavuto omwe amadza posintha ndi kulongosola zinthu kudzera mu njira zosiyanasiyana. Kafukufukuyu akuunikira imodzi mwa njirazi yotchedwa Teaching Development Grant (TDG) yomwe inakonzedwa polimbikitsa maphunziro kudzera mukagwiritsidwe ntchito ka zipangizo zophunzitsira ndi zophunzirira za makono m’sukulu za ukachenjede ku South Africa. Ndalama zapafupifupi R5.5 billion ndi zomwe zaperekedwa kuti zigwiritsidwe nchito mu ndondomekoyi kuchokera pa nthawi yomwe inakhazikitsidwa; zaka khumi zapitazo. Kafukufukuyu anayesera kuyankha funso loti: Ndi zinthu ziti zomwe zimalimbikitsa kapena kubwezeretsa m’mbuyo kagwiritsidwe ntchito ka (TDG) polimbikitsa kuchita bwino kwa aphunzitsi ndi ophunzira m’sukulu za ukachenjede? Zikalata zosonyeza makhonzedwe a ophunzira, ndondomeko za kayendetseredwe ka chuma, zikalata za malipiridwe ndi zikalata zopezeka m’sukulu zaukachenjedezi zokhudzana ndi njira ya TDG zomwe zakhala zikugwiritsidwa ntchito zaka khumi zapitazi zinatengedwanso ngati uthenga wofunika koposa. Kauniuniyu anatsalira njira yotchedwa ‘Archer’s (1995/1996) Morphogenesis/Status Framework’ yomwe imafotokozera momwe kusintha kumachitikira pena kulepherekera. Njira younikira ya Archer: yothandizira pofufuza momwe kayendetsedwe ka bungwe, chikhalidwe komanso anthu oyendetsa bungwe amathandizira poonetsera momwe TDG imakhalira inagwiritsidwa ntchito poyesera kumvetsa zochitika komanso zopezeka mu kafukufukuyu. Chimodzi mwa zotsatira za kafukufukuyu n’chakuti kagwiritsidwe ntchito ka TDG kamabwezeredwa m’mbuyo ndi momwe sukulu za ukachenjede ku South Africa zidapangidwira. Kusiyana kwa usiwa wa zipangizo m’sukuluzi kudapangitsa kuti njira ya TDG isaonetse zipatso kwenikweni. Mu zaka zoyambirira itangokhazikidwitsa (2007 - 2013), sukulu zambiri sizidagwiritse ntchito TDG polimbikitsa kaphunzitsidwe. M’malo mwake ndalama zankhaninkhani zidagwiritsidwa ntchito pa zomangamanga ndi kugulira zipangizo. Usiwa wa zipangizowu ulipobe ndipo ukusokoneza mbali ya maphunziro m’sukulu zokhudzidwazi. Kafukufukuyu anasonyezanso kuti sukulu zomwe zimalandira thandizo lowonjezera pa lomwe zimalandira ku boma zakhala zikuyesetsa kuthana ndi vuto lopereka mochedwa ndalama za mundondomeko ya TDG ndi dongosolo la m’mene ndalamazi zigwirire ntchito. Izi zinawachititsa kuti asapeze mavuto ambiri polimbikitsa ndondomeko za kaphunzitsidwe ndi kaphunziridwe pomwe ena amavutika nazo. Enawa n’kukhala sukulu zomwe sizimachita bwino, zomwenso thandizoli lidalunjika pa izo kuti zithandizike. Kafukufukuyu anasonyeza kuti kuchepa kwa aphunzitsi kudapsinja zochitika zokhudza njirayi. Sukulu zosachita bwino kuchokera kalezi zidavutika kupeza ndi kusunga ogwira ntchito ake. Izi zimakhala choncho kaamba ka zifukwa zosiyanasiyana monga komwe sukuluyo ili, malamulo a ntchito, kupanda ukadaulo kwa oyang’anira antchitowa, kutalikirana ndi njira zina zopezera ndalama komanso kusakhazikika kwa anthu m’maudindo. Zina zotulukanso mu mfundo zotoledwazi zinaulula kuti vuto lina lalikulu linali ogwira ntchito. Polimbikitsa njira ya TDG, zimatanthauza kuti aphunzitsi omwe azilembedwa azikhala osakhazikika pa sukuluzi kapena a kontarakiti. Izi zimatanthauza kuti maphunziro ndi luntha lawo zimayenera kukhala zochepera. Mwanjira ina, tikhonza kunena kuti ogwira ntchitoyi panalibe. Nthawi zina, kusinthasintha kwa ndondomeko zachuma madongosolo ena kusiyidwa kapena kuchitika mosalongosoka. Kafukufukuyu anasonyezanso kuti zambiri mwa mfundo zomwe zinayikidwa kuti zigwiritsidwe ntchito zinali zosathandiza kwenikweni polimbikitsa maphunzirowa. Ndipo komwe mfundozi zinakhazikitsidwa, zinali chabe kufotokozera zinthu zodziwika kale ndi kale zokhudza zomwe zingalimbikitse uphunzitsi. M’sukulu zambiri za ukachenjede, pali umboni wochepa wa mfundo zomwe zinaikidwiratu ndi cholinga chopititsa patsogolo uphunzitsiwu. Kusowa kwa ukadaulo pa maphunzirowa kunaonekanso makamaka m’madera monga a oyendetsa sukuluzi, oyang’ana za chuma, olongosola malo onse komanso oyang’anira antchito. Panalibe kugawana anthuwa mofanana. Izi zidakhudza kwambiri kalondolondo ndinso kayendetsedwe ka TDG. Kusowa kwa ndondomeko zabwino ndi malamulo okhazikika kunalimbikitsa chikhalidwe cha chinyengo ndi kusatsatira mfundo za mundondomekoyi popereka utsogoleri ndi umwini ndiye unali wofunika polimbikitsa ndondomekoyi. Madongosolo otere anathandiza kuti sukulu zigwiritse ntchito njira ya TDG ndipo pena ndalama mamiliyoni zibwezedwe. Kafukufukuyu anaonetsa kuti kulephera kwa sukulu zina kugwiritsa ntchito ndalama kunachitika kaamba kosazindikira malire a chaka cha DHET ndi chaka cha maphunziro. Ngakhale njira ya TDG yathandizako kagwiritsidwe ntchito ka zipangizo zophunzitsira ndi zophunzirira, kafukufukuyu wasonyeza kuti mavuto omwe anaoneka mu ndondomeko ya TDG aphimba ubwino wake. Monga, m’chitidwe wobweza ndalama zosagwira ntchito unalunjika pa kulephera kugwiritsa ntchito ndalama zonse osati pa ubale pakati pa kayendetsedwe ka bungwe, chikhalidwe ndinso anthu oyendetsa bungwe. Ndalama zotsarazi zinalowetsedwa ku zitukuko zina ndi boma. Koma poti sukulu zonse za ukachenjede kuphatikizapo HAI zinapeza mwayi wa ndalamazi, izi zimabweretsa kulowa pansi kwa dongosolo la TDG. Kulephera mu DHET kutsogolera, kuyendetsa ndi kulondoloza thandizo kwadzetsanso mavuto pa kagwiritsidwe ntchito kake ngakhalenso kutumizidwa kwa katswiri pa kaphunzitsidwe kunaoneka ngati kofunika kosathandiza kwenikweni chifukwa kudali kwa nthawi yochepa. Zotsatira za kafukufukuyu (zokhudza maphunziro a ukachenjede ku South Africa) ndi zofunika kwambiri makamaka nthawi ino pomwe TDG pamodzi ndi RDG (Research Development Grant) zikhale kuunikiridwanso ndi kupanga thandizo latsopano lotchedwa University Capacity Development Grant kuyambira m’chaka cha 2018. Kafukufukuyu waunika mozama kayendetsedwe, chikhalidwe komanso oyendetsa zithandizo komanso mavuto kuti thandizo latsopanoli likathe kubweretsa kusintha. Zotsatirazi zaunikiranso kayendetsedwe ka zithandizo zina zomwe zikufuna kuchitika.
- Full Text:
- Date Issued: 2018
An assessment of the effect of implementation of performance management system on organizational performance : a case of selected public organizations in Tanzania
- Authors: Nduye, Jacob Gabriel
- Date: 2018
- Subjects: Personnel management Organizational effectiveness
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/10573 , vital:35609
- Description: Tanzanians continue to demand improved performances and better-quality services from public organizations and the government at large. Since independence in 1961, the Tanzanian government continued to undertake a restructuring of different policies, laws and regulations in public services to improve performances and service delivery. Among the results of the restructuring was introduction of Performance Management System(PMS) across public organizations. The system meant to address and redress not only the concerns of the public on improved performances and better services, but also inculcate performance-oriented culture and accountability for results. Despite such efforts by the government, some of the problems existed before the introduction of PMS such as among others weak incentives and accountabilities, and management skills continue to impede issues of improved performance and service delivery in public organizations. It is from this context that the researcher was encouraged to research on issues of performance management system, highlighting specific areas of its effectiveness to improve performance, motivational factors, use of performance appraisal results on different decisions-making and factors for underperformances which affect organizational performances in public organizations. This study employed a mixed method research design involving both quantitative and qualitative strategies. For the qualitative strategy, data were gathered using in-depth interviews and document reviews; and for the quantitative strategy, questionnaires were used in which the relationship of different variables for the study were statistically analyzed using the SPSS Version 22. In the overall, the study evidences show a strong pressure of support at government level in terms of formulating policies, laws and regulations to back up performance management system to improve performance quality service delivery, but there is less support in public organizations levels. It became clear that many problems still make PMS effectiveness not pragmatic: Political interferences to management of public organizations, government bureaucratic procedures in amendments of outdated laws, inflexible scheme of services important for rewards and incentives and the use of manual voting system for good performances are among problems that the study identified. Furthermore, evidences have shown that a top-down management approach bottlenecks the overall implementation of performance enhancing tools for performance management system effectiveness. There is lack of workers’ participation and ownership of tools such as, strategic plans, client service charters and open performance reviews and appraisal system and the general system, and thus becoming hard to implement it in the public organizations. The study suggests practical initiatives by the government to establish highly strict quality service delivery satisfaction tracking system to allow both employees and citizens to evaluate internal and external performances of the public organizations. The findings upheld vulnerability of PMS to improve performance and service delivery, and therefore more attention and adherence to principles of performance management and laws that are biting to issues of underperformances are imperative.
- Full Text:
- Date Issued: 2018
- Authors: Nduye, Jacob Gabriel
- Date: 2018
- Subjects: Personnel management Organizational effectiveness
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/10573 , vital:35609
- Description: Tanzanians continue to demand improved performances and better-quality services from public organizations and the government at large. Since independence in 1961, the Tanzanian government continued to undertake a restructuring of different policies, laws and regulations in public services to improve performances and service delivery. Among the results of the restructuring was introduction of Performance Management System(PMS) across public organizations. The system meant to address and redress not only the concerns of the public on improved performances and better services, but also inculcate performance-oriented culture and accountability for results. Despite such efforts by the government, some of the problems existed before the introduction of PMS such as among others weak incentives and accountabilities, and management skills continue to impede issues of improved performance and service delivery in public organizations. It is from this context that the researcher was encouraged to research on issues of performance management system, highlighting specific areas of its effectiveness to improve performance, motivational factors, use of performance appraisal results on different decisions-making and factors for underperformances which affect organizational performances in public organizations. This study employed a mixed method research design involving both quantitative and qualitative strategies. For the qualitative strategy, data were gathered using in-depth interviews and document reviews; and for the quantitative strategy, questionnaires were used in which the relationship of different variables for the study were statistically analyzed using the SPSS Version 22. In the overall, the study evidences show a strong pressure of support at government level in terms of formulating policies, laws and regulations to back up performance management system to improve performance quality service delivery, but there is less support in public organizations levels. It became clear that many problems still make PMS effectiveness not pragmatic: Political interferences to management of public organizations, government bureaucratic procedures in amendments of outdated laws, inflexible scheme of services important for rewards and incentives and the use of manual voting system for good performances are among problems that the study identified. Furthermore, evidences have shown that a top-down management approach bottlenecks the overall implementation of performance enhancing tools for performance management system effectiveness. There is lack of workers’ participation and ownership of tools such as, strategic plans, client service charters and open performance reviews and appraisal system and the general system, and thus becoming hard to implement it in the public organizations. The study suggests practical initiatives by the government to establish highly strict quality service delivery satisfaction tracking system to allow both employees and citizens to evaluate internal and external performances of the public organizations. The findings upheld vulnerability of PMS to improve performance and service delivery, and therefore more attention and adherence to principles of performance management and laws that are biting to issues of underperformances are imperative.
- Full Text:
- Date Issued: 2018
An assessment study of the role of life orientation teachers in promoting career guidance and counselling of secondary school learners in the Vhembe district of Limpopo province, South Africa
- Authors: Dama, Nkhangweleni Gloria
- Date: 2018
- Subjects: Counseling in secondary education -- South Africa -- Limpopo Life skills -- Study and teaching (Secondary) -- South Africa -- Limpopo
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9577 , vital:34794
- Description: The study sought to assess the role of Life Orientation teachers in promoting Career Guidance and Counselling for learners in secondary schools, and to establish strategies that can be implemented to improve their practice. The study followed a qualitative approach with case-study research design. The population consisted of Life Orientation teachers and learners from secondary schools. Purposive sampling was used to select 18 Life Orientation teachers who are teaching the subject in six secondary schools. A total number of 12 learners from Grade 10- 12 were selected to participate in the study. The study employed three data collection instruments; namely, one-on-one interviews, focus group discussions and questaviews. Data were categorised into themes, analysed and discussed accordingly. A number of findings emanated from the study. Life Orientation teachers understand their role but despite their understanding of such roles, they lack the necessary skills to fully equip learners with relevant knowledge so that they are able to choose careers that match with their subjects of specialization. The study revealed that Life Orientation teachers experience challenges, lack of training, lack of support by different stakeholders, the negative attitude towards the subject by both learners and Life Orientation teachers, the shortage of Life Orientation teachers, the subject is not valued like other subjects, poor parental involvement by parents and constant rotation of Life Orientation teachers. As a result, learners were not fully equipped in terms of knowledge and skills to choose the right subjects for specific careers and instead, some relied on their intuition while others relied on their peers. The study recommended that the Department of the Basic Education should appoint competent staff to address the unique academic/educational, psycho-social and career/vocational problems faced by learners in school, and for them to train the Life Orientation teachers as well. The subject should be taught by permanently by qualified teachers without being shifted to other subjects and to ensure that such teachers gain experience in the subject. This would add status and value to the subject.
- Full Text:
- Date Issued: 2018
- Authors: Dama, Nkhangweleni Gloria
- Date: 2018
- Subjects: Counseling in secondary education -- South Africa -- Limpopo Life skills -- Study and teaching (Secondary) -- South Africa -- Limpopo
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9577 , vital:34794
- Description: The study sought to assess the role of Life Orientation teachers in promoting Career Guidance and Counselling for learners in secondary schools, and to establish strategies that can be implemented to improve their practice. The study followed a qualitative approach with case-study research design. The population consisted of Life Orientation teachers and learners from secondary schools. Purposive sampling was used to select 18 Life Orientation teachers who are teaching the subject in six secondary schools. A total number of 12 learners from Grade 10- 12 were selected to participate in the study. The study employed three data collection instruments; namely, one-on-one interviews, focus group discussions and questaviews. Data were categorised into themes, analysed and discussed accordingly. A number of findings emanated from the study. Life Orientation teachers understand their role but despite their understanding of such roles, they lack the necessary skills to fully equip learners with relevant knowledge so that they are able to choose careers that match with their subjects of specialization. The study revealed that Life Orientation teachers experience challenges, lack of training, lack of support by different stakeholders, the negative attitude towards the subject by both learners and Life Orientation teachers, the shortage of Life Orientation teachers, the subject is not valued like other subjects, poor parental involvement by parents and constant rotation of Life Orientation teachers. As a result, learners were not fully equipped in terms of knowledge and skills to choose the right subjects for specific careers and instead, some relied on their intuition while others relied on their peers. The study recommended that the Department of the Basic Education should appoint competent staff to address the unique academic/educational, psycho-social and career/vocational problems faced by learners in school, and for them to train the Life Orientation teachers as well. The subject should be taught by permanently by qualified teachers without being shifted to other subjects and to ensure that such teachers gain experience in the subject. This would add status and value to the subject.
- Full Text:
- Date Issued: 2018
An investigation into the bacterial biosynthetic origins of bioactive natural products isolated from South African latrunculid sponges
- Authors: Waterworth, Samantha Che
- Date: 2018
- Subjects: Marine biodiversity , Metagenomics , Sponges Biotechnology , Spirochetes , Natural products Biotechnology
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/61826 , vital:28065
- Description: Several pyrroloiminoquinone alkaloids exhibiting cytotoxic, anti-tumour activity have been isolated from sponges within the Latrunculiidae family that are endemic to the South African coastline. Other, structurally similar pyrroloiminoquinone compounds have been isolated from geographically distant and phylogenetically distinct marine sponges, as well as terrestrial myxomycetes which suggested that sponge-associated bacteria may be the true biosynthetic origin of pyrroloiminoquinone compounds. Previous studies have shown that there is conservation of spirochete and betaproteobacterial species in the bacterial communities associated with South African Latrunculiidae sponges and it was proposed that these conserved bacteria represented candidate pyrroloiminoquinone-producers. This study aimed to confirm the conserved dominance of betaproteobacteria and spirochetes within bacterial communities associated with South African latrunculid sponges and employed a shotgun metagenomic approach to assess the functional and biosynthetic potential of associated microbiota in Tsitsikamma favus sponges. Clustering of assembled contigs revealed twenty-three putative bacterial genomes, of which, two were identified as representatives of the conserved betaproteobacteria and spirochete species previously identified in Tsitsikamma sponges. It was shown that the spirochete was most likely an obligate symbiont that benefitted the host sponge through possible defence against pathogenic bacteria and/or nutrient acquisition. The putative genome representing the conserved betaproteobacteria was found to be heavily contaminated and further sequencing is required to accurately resolve the genome for functional characterization. Several biosynthetic gene clusters were identified and demonstrated the bioactive potential of Tsitsikamma favus-associated bacteria. A biosynthetic gene cluster was identified on an unclustered contig that included several genetic features that were indicative of possible pyrroloiminoquinone production.
- Full Text:
- Date Issued: 2018
- Authors: Waterworth, Samantha Che
- Date: 2018
- Subjects: Marine biodiversity , Metagenomics , Sponges Biotechnology , Spirochetes , Natural products Biotechnology
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/61826 , vital:28065
- Description: Several pyrroloiminoquinone alkaloids exhibiting cytotoxic, anti-tumour activity have been isolated from sponges within the Latrunculiidae family that are endemic to the South African coastline. Other, structurally similar pyrroloiminoquinone compounds have been isolated from geographically distant and phylogenetically distinct marine sponges, as well as terrestrial myxomycetes which suggested that sponge-associated bacteria may be the true biosynthetic origin of pyrroloiminoquinone compounds. Previous studies have shown that there is conservation of spirochete and betaproteobacterial species in the bacterial communities associated with South African Latrunculiidae sponges and it was proposed that these conserved bacteria represented candidate pyrroloiminoquinone-producers. This study aimed to confirm the conserved dominance of betaproteobacteria and spirochetes within bacterial communities associated with South African latrunculid sponges and employed a shotgun metagenomic approach to assess the functional and biosynthetic potential of associated microbiota in Tsitsikamma favus sponges. Clustering of assembled contigs revealed twenty-three putative bacterial genomes, of which, two were identified as representatives of the conserved betaproteobacteria and spirochete species previously identified in Tsitsikamma sponges. It was shown that the spirochete was most likely an obligate symbiont that benefitted the host sponge through possible defence against pathogenic bacteria and/or nutrient acquisition. The putative genome representing the conserved betaproteobacteria was found to be heavily contaminated and further sequencing is required to accurately resolve the genome for functional characterization. Several biosynthetic gene clusters were identified and demonstrated the bioactive potential of Tsitsikamma favus-associated bacteria. A biosynthetic gene cluster was identified on an unclustered contig that included several genetic features that were indicative of possible pyrroloiminoquinone production.
- Full Text:
- Date Issued: 2018
An investigation into the introduction of a new wealth tax in South Africa
- Authors: Arendse, Jacqueline A
- Date: 2018
- Subjects: Wealth tax -- Law and legislation -- South Africa , Taxation -- Law and legislation -- South Africa , Income tax -- South Africa , Fiscal policy -- South Africa , South Africa -- Economic conditions , Income distribution -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/61379 , vital:28020
- Description: In a world of economic uncertainty and manifold social problems, South Africa has its own unique challenges of low economic growth, persistent budget deficits that produce increasing government debt and the highest level of economic inequality in the world. The history of injustice and economic marginalisation and the failure of the economy to provide inclusive growth drives an urgent need to address economic inequality through tax policy, placing ever more focus on wealth taxes as a possible solution. There is a hope is that taxing the wealthy may provide the opportunity to redistribute desperately-needed resources to those denied the opportunity to build wealth and who are trapped in the cycle of poverty. Yet, as appealing as a new wealth tax may seem, the introduction of such a tax carries with it a range of risks, not all of which are known. Of great concern is the possible effect on the economy, which, in its vulnerable state, cannot afford any loss of capital and investment. Very little research has been done on wealth tax in the South African context and there is a dearth of literature focusing on the views and perceptions of the wealthy individuals themselves. This qualitative study investigates the merits and disadvantages of a new wealth tax and seeks to identify any unintended consequences that could result from the implementation of a new wealth tax in South Africa, drawing from historical and international experience and primary data obtained from interviews with individuals likely to be affected by such a tax. Having explored the literature and international experiences with wealth tax and having probed the thinking of wealthy individuals who would be the payers of a wealth tax, the study finds that a new wealth tax may contribute towards the progressivity of the tax system, but it is doubtful whether such a tax would provide a sustainable revenue stream that would be sufficient to address economic inequality and there is a risk of causing harm to the economy. Recognising that the motivation for wealth taxes is often driven more by political argument and public perception than by rational quantitative analysis, the study also anticipates the introduction of a new wealth tax and suggests guidelines for the design of such a tax within the framework for evaluating a good tax system. This study informs the debate on wealth taxes in South Africa and contributes to the design of such a tax, should it be implemented.
- Full Text:
- Date Issued: 2018
- Authors: Arendse, Jacqueline A
- Date: 2018
- Subjects: Wealth tax -- Law and legislation -- South Africa , Taxation -- Law and legislation -- South Africa , Income tax -- South Africa , Fiscal policy -- South Africa , South Africa -- Economic conditions , Income distribution -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/61379 , vital:28020
- Description: In a world of economic uncertainty and manifold social problems, South Africa has its own unique challenges of low economic growth, persistent budget deficits that produce increasing government debt and the highest level of economic inequality in the world. The history of injustice and economic marginalisation and the failure of the economy to provide inclusive growth drives an urgent need to address economic inequality through tax policy, placing ever more focus on wealth taxes as a possible solution. There is a hope is that taxing the wealthy may provide the opportunity to redistribute desperately-needed resources to those denied the opportunity to build wealth and who are trapped in the cycle of poverty. Yet, as appealing as a new wealth tax may seem, the introduction of such a tax carries with it a range of risks, not all of which are known. Of great concern is the possible effect on the economy, which, in its vulnerable state, cannot afford any loss of capital and investment. Very little research has been done on wealth tax in the South African context and there is a dearth of literature focusing on the views and perceptions of the wealthy individuals themselves. This qualitative study investigates the merits and disadvantages of a new wealth tax and seeks to identify any unintended consequences that could result from the implementation of a new wealth tax in South Africa, drawing from historical and international experience and primary data obtained from interviews with individuals likely to be affected by such a tax. Having explored the literature and international experiences with wealth tax and having probed the thinking of wealthy individuals who would be the payers of a wealth tax, the study finds that a new wealth tax may contribute towards the progressivity of the tax system, but it is doubtful whether such a tax would provide a sustainable revenue stream that would be sufficient to address economic inequality and there is a risk of causing harm to the economy. Recognising that the motivation for wealth taxes is often driven more by political argument and public perception than by rational quantitative analysis, the study also anticipates the introduction of a new wealth tax and suggests guidelines for the design of such a tax within the framework for evaluating a good tax system. This study informs the debate on wealth taxes in South Africa and contributes to the design of such a tax, should it be implemented.
- Full Text:
- Date Issued: 2018
An investigation of the combustion kinetics of coal-microalgae composite
- Ejesieme, Obialo Vitus, Dugmore, Gary
- Authors: Ejesieme, Obialo Vitus , Dugmore, Gary
- Date: 2018
- Subjects: Microalgae -- Biotechnology , Biomass energy -- South Africa Coal -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/34777 , vital:33447
- Description: Coal mining and handling generate sizeable quantities of ultra-fine coal particles which are heaped as discard material. Use of the ultra-fine coal for co-firing with microalgae biomass appears to be a promising option that would improve combustion of the discard. There is no available traditional biomass binder that can be used to agglomerate, reclaim, and co-fire the discard ultra-fine coal to generate heat. In a recent research, microalgae biomass was identified as an effective natural binder for discard ultra-fine coal. Biomass is a renewable resource, and many have been co-fired on a large scale except microalgae biomass. Researchers have studied co-firing of dry mixed coal-microalgae, however, the kinetics of a wet mix of microalgae biomass and ultra-fine coal, “Coalgae®” patented recently by the Nelson Mandela University needs to be explored. The study aimed at investigating in some detail the oxidation mechanism of coal-microalgae composites. The objective is to understand the impact of microalgae on the kinetic properties of coal which will inform on the application of “Coalgae®”. It involves correlating the small and large-scale combustion properties that will establish the co-firing option on an industrial scenario. The goal is to utilize all grades of discard ultra-fine resource using microalgae biomass as binder and a renewable component which enhances the combustion of coal to supply heat and electricity. The use of microalgae for fuel preparation and upgrading is on the increase due to its high growth potential, reactivity, and ability to store energy more than other biomasses. This research hypothesized that blending of discard ultra-fine coal with live microalgae biomass would improve the kinetic properties of the coal more than expected from linear combination of the dry materials. Thermogravimetric combustion of “Coalgae®” was studied under non-isothermal conditions from 40 °C to 900°C at a heating rate of 15 °C/min and air flow rate of 20 ml/min. The thermogravimetric combustion properties i.e. small-scale was related to the large-scale, John Thompson’s fixed-bed reactor under the above condition. Thermal profiles were transformed into a differential function to reveal overlapped combustion events. The Coat-Redferns kinetic model was applied on the non-de-Ejesieme, O.V. PhD Chemistry (Research), Nelson Mandela Univ. Email: ejevit@yahoo.com , s211266744@live.nmmu.ac.za convoluted reactions set to obtain some of kinetic parameters. The Fraser-Suzuki equation was used to de-convolute the overlapped combustion. Then, rate law combined with Arrhenius equation was used to derive the activation energy E a and pre-exponential factor A, while the integral form of solid states reaction model, g (∝) was applied to deduce the oxidation mechanism. The composite formed a strong and partly renewable blend under controlled temperature conditions, unlike assorted dried biomass mixed with coal. Microalgae biomass upgraded the fuel and kinetics properties of ultra-fine coal more than what was expected from a linear combination. It released heat that promoted the oxidation mechanism of the discard coal. The main effect is that the “Coalgae®” is significantly (p = 0.0570) more reactive than the coal. The co-firing approach is partly renewable and contributes to the utilization of high and low-quality available discard ultra-fine coal. It advances the combustion of coal resources and reduces carbon dioxide, CO2 emission attributed to global warming as well as preserves the natural biomass sources. The combustion of “Coalgae® “will improve economy, environment, and health, heat, and electricity supply to the society.
- Full Text:
- Date Issued: 2018
- Authors: Ejesieme, Obialo Vitus , Dugmore, Gary
- Date: 2018
- Subjects: Microalgae -- Biotechnology , Biomass energy -- South Africa Coal -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/34777 , vital:33447
- Description: Coal mining and handling generate sizeable quantities of ultra-fine coal particles which are heaped as discard material. Use of the ultra-fine coal for co-firing with microalgae biomass appears to be a promising option that would improve combustion of the discard. There is no available traditional biomass binder that can be used to agglomerate, reclaim, and co-fire the discard ultra-fine coal to generate heat. In a recent research, microalgae biomass was identified as an effective natural binder for discard ultra-fine coal. Biomass is a renewable resource, and many have been co-fired on a large scale except microalgae biomass. Researchers have studied co-firing of dry mixed coal-microalgae, however, the kinetics of a wet mix of microalgae biomass and ultra-fine coal, “Coalgae®” patented recently by the Nelson Mandela University needs to be explored. The study aimed at investigating in some detail the oxidation mechanism of coal-microalgae composites. The objective is to understand the impact of microalgae on the kinetic properties of coal which will inform on the application of “Coalgae®”. It involves correlating the small and large-scale combustion properties that will establish the co-firing option on an industrial scenario. The goal is to utilize all grades of discard ultra-fine resource using microalgae biomass as binder and a renewable component which enhances the combustion of coal to supply heat and electricity. The use of microalgae for fuel preparation and upgrading is on the increase due to its high growth potential, reactivity, and ability to store energy more than other biomasses. This research hypothesized that blending of discard ultra-fine coal with live microalgae biomass would improve the kinetic properties of the coal more than expected from linear combination of the dry materials. Thermogravimetric combustion of “Coalgae®” was studied under non-isothermal conditions from 40 °C to 900°C at a heating rate of 15 °C/min and air flow rate of 20 ml/min. The thermogravimetric combustion properties i.e. small-scale was related to the large-scale, John Thompson’s fixed-bed reactor under the above condition. Thermal profiles were transformed into a differential function to reveal overlapped combustion events. The Coat-Redferns kinetic model was applied on the non-de-Ejesieme, O.V. PhD Chemistry (Research), Nelson Mandela Univ. Email: ejevit@yahoo.com , s211266744@live.nmmu.ac.za convoluted reactions set to obtain some of kinetic parameters. The Fraser-Suzuki equation was used to de-convolute the overlapped combustion. Then, rate law combined with Arrhenius equation was used to derive the activation energy E a and pre-exponential factor A, while the integral form of solid states reaction model, g (∝) was applied to deduce the oxidation mechanism. The composite formed a strong and partly renewable blend under controlled temperature conditions, unlike assorted dried biomass mixed with coal. Microalgae biomass upgraded the fuel and kinetics properties of ultra-fine coal more than what was expected from a linear combination. It released heat that promoted the oxidation mechanism of the discard coal. The main effect is that the “Coalgae®” is significantly (p = 0.0570) more reactive than the coal. The co-firing approach is partly renewable and contributes to the utilization of high and low-quality available discard ultra-fine coal. It advances the combustion of coal resources and reduces carbon dioxide, CO2 emission attributed to global warming as well as preserves the natural biomass sources. The combustion of “Coalgae® “will improve economy, environment, and health, heat, and electricity supply to the society.
- Full Text:
- Date Issued: 2018
An investigation of the correlation of mitochondrial biogenesis, mitochondrial DNA methylation, mitochondrial network topology and adipogenesis in the human adipose-derived mesenchymal stromal stem cell model
- Authors: Kadye, Rose
- Date: 2018
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62637 , vital:28222
- Description: Expected release date-April 2019
- Full Text:
- Date Issued: 2018
- Authors: Kadye, Rose
- Date: 2018
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62637 , vital:28222
- Description: Expected release date-April 2019
- Full Text:
- Date Issued: 2018
An investigation of the teaching of reading in isiXhosa in three Grade 1 classrooms in the Eastern Cape, South Africa
- Authors: Magadla, Noluthando
- Date: 2018
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/63408 , vital:28408
- Full Text: false
- Date Issued: 2018
- Authors: Magadla, Noluthando
- Date: 2018
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/63408 , vital:28408
- Full Text: false
- Date Issued: 2018
Analysis of the human HSP70-HSP90 organising protein (HOP) gene - characterisation of the promoter and identification of a novel isoform
- Authors: Mattison, Stacey
- Date: 2018
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62821 , vital:28296
- Description: Expected release date-April 2020
- Full Text:
- Date Issued: 2018
- Authors: Mattison, Stacey
- Date: 2018
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62821 , vital:28296
- Description: Expected release date-April 2020
- Full Text:
- Date Issued: 2018
Aspects Allocentristes de l’Humanisme dans l’Univers Romanesque de Williams Sassine
- Authors: Dami, Emmanuel Naancin
- Date: 2018
- Subjects: Sassine, Williams, 1944-1997 -- Criticism and interpretation , Guinean fiction (French) -- 20th century -- History and criticism , Humanism in literature , Human beings in literature , Postcolonialism in literature , Existentialism in literature
- Language: French , English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/61957 , vital:28089
- Description: The human being, his behaviour and more importantly, his very essence have, for time immemorial, proven to be enigmatic to many a man and to researchers in particular. Consequently, the need for a thorough and more profound understanding of man has made him the epicentre of epistemic investigations across many academic disciplines. This, unfortunately, does not seem to have shaded bright lights on the grey areas bordering on his nature to his behavior. This, in turn, opens up other windows requiring further probes. For instance, proponents of the Neo-classical economic school contend that the human being is homo oeconomicus. This implies that man is intrinsically egocentric and a rational being whose decisions are based on informed choices driven by his urge for maximal utility geared towards his personal satisfaction (O’Boyle 2009; Caruso 2012). This stance invalidates man’s ability to do ‘disinterested good’ in any form. African francophone literature is replete with different and diverse images of man, his behaviour and existential conditions: sufferings and struggles. It, therefore, constitutes, inter alia, a laboratory in which researchers undertake investigative endeavours. This thesis beams its floodlights on the allocentric aspects of humanism in the novels of Williams Sassine. Thus, using the phenomenological and ‘clavieniste’ lenses as overarching operational theories, the thesis investigates Sassine’s novels with the view to shading a ray of light on the ‘humanistic man’ especially the allocentric dimensions of his nature and comportment. Emphasis is laid on the motives and motivations underlying the individual and the in-group struggle of the sassinien heroes in the emancipation of their society from the shackles of colonial and postcolonial domination, exploitation and subjugation resulting in self-determination and the subsequent disenchantment. Furthermore, the thesis examines the nature and character of human charity, generosity and sacrifices among the characters in the novels. In conclusion, the thesis establishes, through an x-ray of the nature of actions and decisions of certain characters in the novels, the examination of the conscious and subconscious intentions underlying these same actions and decisions which, on a face value, are apparently altruistic, that the sassinien heroes’ efforts and sacrifices are geared towards the common and greater good. This invariably means that man is, indeed, capable of posing disinterested acts of charity and bringing succour, devoid of any ulterior motives for personal gain, to his fellow humans. The position of the Neo-classical economists is consequently over-assuming, sweeping and tad generalizing. The sassinien characters have demonstrated beyond reasonable doubt that they are humanists. Their nature, the remote and immediate causes of their fights, the goals and objectives of their struggles and their spirit of abnegation have indeed proven that “human beings have the right and the responsibility to give meaning and shape to their own lives. [They have stood] for the building of a more humane society through an ethics based on the human and other natural values in a spirit of reason and free inquiry through human capabilities” (AHA 2017 : 3).
- Full Text:
- Date Issued: 2018
- Authors: Dami, Emmanuel Naancin
- Date: 2018
- Subjects: Sassine, Williams, 1944-1997 -- Criticism and interpretation , Guinean fiction (French) -- 20th century -- History and criticism , Humanism in literature , Human beings in literature , Postcolonialism in literature , Existentialism in literature
- Language: French , English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/61957 , vital:28089
- Description: The human being, his behaviour and more importantly, his very essence have, for time immemorial, proven to be enigmatic to many a man and to researchers in particular. Consequently, the need for a thorough and more profound understanding of man has made him the epicentre of epistemic investigations across many academic disciplines. This, unfortunately, does not seem to have shaded bright lights on the grey areas bordering on his nature to his behavior. This, in turn, opens up other windows requiring further probes. For instance, proponents of the Neo-classical economic school contend that the human being is homo oeconomicus. This implies that man is intrinsically egocentric and a rational being whose decisions are based on informed choices driven by his urge for maximal utility geared towards his personal satisfaction (O’Boyle 2009; Caruso 2012). This stance invalidates man’s ability to do ‘disinterested good’ in any form. African francophone literature is replete with different and diverse images of man, his behaviour and existential conditions: sufferings and struggles. It, therefore, constitutes, inter alia, a laboratory in which researchers undertake investigative endeavours. This thesis beams its floodlights on the allocentric aspects of humanism in the novels of Williams Sassine. Thus, using the phenomenological and ‘clavieniste’ lenses as overarching operational theories, the thesis investigates Sassine’s novels with the view to shading a ray of light on the ‘humanistic man’ especially the allocentric dimensions of his nature and comportment. Emphasis is laid on the motives and motivations underlying the individual and the in-group struggle of the sassinien heroes in the emancipation of their society from the shackles of colonial and postcolonial domination, exploitation and subjugation resulting in self-determination and the subsequent disenchantment. Furthermore, the thesis examines the nature and character of human charity, generosity and sacrifices among the characters in the novels. In conclusion, the thesis establishes, through an x-ray of the nature of actions and decisions of certain characters in the novels, the examination of the conscious and subconscious intentions underlying these same actions and decisions which, on a face value, are apparently altruistic, that the sassinien heroes’ efforts and sacrifices are geared towards the common and greater good. This invariably means that man is, indeed, capable of posing disinterested acts of charity and bringing succour, devoid of any ulterior motives for personal gain, to his fellow humans. The position of the Neo-classical economists is consequently over-assuming, sweeping and tad generalizing. The sassinien characters have demonstrated beyond reasonable doubt that they are humanists. Their nature, the remote and immediate causes of their fights, the goals and objectives of their struggles and their spirit of abnegation have indeed proven that “human beings have the right and the responsibility to give meaning and shape to their own lives. [They have stood] for the building of a more humane society through an ethics based on the human and other natural values in a spirit of reason and free inquiry through human capabilities” (AHA 2017 : 3).
- Full Text:
- Date Issued: 2018
Aspects of the nutritional physiology of the perlemoen Haliotis midae (L.) and red abalone H. rufescens (Swainson)
- Authors: Kemp, Justin Oliver Gordon
- Date: 2018
- Subjects: Haliotis midae , Haliotis midae fisheries , Red abalone , Haliotis midae -- Feeding and feeds , Red abalone -- Feeding and feeds , Haliotis midae -- Nutrition -- Requirements , Red abalone -- Nutrition -- Requirements , Haliotis midae -- Metabolism , Red abalone -- Metabolism , Haliotis midae -- Physiology , Red abalone -- Physiology , Stable isotopes , Algae as feed
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62314 , vital:28154
- Description: The source of abalone for human consumption has shown a dramatic shift away from wild-capture fisheries in the last 30 years, with over 90% of global production now coming from aquaculture. Farmers initially relied on the natural food of abalone (macroalgae) as a culture feed, though in regions where macroalgae availability was limiting, the need to develop formulated feeds was evident. Extensive research effort has led to the development of a number of formulated feed products currently employed in the industry. These feeds, however, differ markedly from the mixed macroalgal diets that abalone have evolved to utilise, particularly in terms of protein content and carbohydrate structure. The degree to which the nutritional physiology of abalone responds to these novel formulated diets, with and without macroalgal supplementation, was investigated in the current study. A multifaceted approach, combining growth trials, stable isotope nutrient tracers and metabolic experiments, was employed to gain insight into the post-absorption dynamics and utilisation of dietary nutrients under varying dietary regimes of fresh macroalgae and formulated feed. Growth trials conducted with both Haliotis rufescens and H. midae showed significantly higher growth and protein utilisation efficiency for abalone fed macroalgal diets compared to formulated feeds. Furthermore, when formulated feeds were supplemented with macroalgae to form combination diets, growth and the utilization of protein was improved compared to the formulated-feed-only diet. The poor utilisation of protein by H. midae fed the formulated feed could be traced, using a method combining stable isotope bio-markers with a Bayesian mixing model (SIAR), to the low incorporation of the fishmeal component of protein in the diet. The marked postprandial drop in the O:N ratio on abalone fed formulated feeds indicate that the protein was being diverted into catabolic metabolic pathways. The metabolic cost of digestion, termed specific dynamic action (SDA), was negated as a factor in the improved growth of abalone fed macroalgal diets, with the SDA coefficient 2.1 times that observed for formulated feed. Furthermore, the postprandial haemolymph glucose concentration (HGC) in H. midae was elevated when fed formulated feed compared to macroalgae. The high levels of circulating glucose are likely a result of the structure the carbohydrate source in formulated feeds and stimulate the deposition of glycogen through the allosteric control of glycogen synthase. Formulated feeds produced higher cooked meat yields in canning simulation trials, suggesting that muscle glycogen content may indirectly play a role in increasing canning yields through the displacement of collagen. The results of these empirical studies are synthesised under key themes, discussed within the context of their potential commercial relevance and future research directions are highlighted.
- Full Text:
- Date Issued: 2018
- Authors: Kemp, Justin Oliver Gordon
- Date: 2018
- Subjects: Haliotis midae , Haliotis midae fisheries , Red abalone , Haliotis midae -- Feeding and feeds , Red abalone -- Feeding and feeds , Haliotis midae -- Nutrition -- Requirements , Red abalone -- Nutrition -- Requirements , Haliotis midae -- Metabolism , Red abalone -- Metabolism , Haliotis midae -- Physiology , Red abalone -- Physiology , Stable isotopes , Algae as feed
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62314 , vital:28154
- Description: The source of abalone for human consumption has shown a dramatic shift away from wild-capture fisheries in the last 30 years, with over 90% of global production now coming from aquaculture. Farmers initially relied on the natural food of abalone (macroalgae) as a culture feed, though in regions where macroalgae availability was limiting, the need to develop formulated feeds was evident. Extensive research effort has led to the development of a number of formulated feed products currently employed in the industry. These feeds, however, differ markedly from the mixed macroalgal diets that abalone have evolved to utilise, particularly in terms of protein content and carbohydrate structure. The degree to which the nutritional physiology of abalone responds to these novel formulated diets, with and without macroalgal supplementation, was investigated in the current study. A multifaceted approach, combining growth trials, stable isotope nutrient tracers and metabolic experiments, was employed to gain insight into the post-absorption dynamics and utilisation of dietary nutrients under varying dietary regimes of fresh macroalgae and formulated feed. Growth trials conducted with both Haliotis rufescens and H. midae showed significantly higher growth and protein utilisation efficiency for abalone fed macroalgal diets compared to formulated feeds. Furthermore, when formulated feeds were supplemented with macroalgae to form combination diets, growth and the utilization of protein was improved compared to the formulated-feed-only diet. The poor utilisation of protein by H. midae fed the formulated feed could be traced, using a method combining stable isotope bio-markers with a Bayesian mixing model (SIAR), to the low incorporation of the fishmeal component of protein in the diet. The marked postprandial drop in the O:N ratio on abalone fed formulated feeds indicate that the protein was being diverted into catabolic metabolic pathways. The metabolic cost of digestion, termed specific dynamic action (SDA), was negated as a factor in the improved growth of abalone fed macroalgal diets, with the SDA coefficient 2.1 times that observed for formulated feed. Furthermore, the postprandial haemolymph glucose concentration (HGC) in H. midae was elevated when fed formulated feed compared to macroalgae. The high levels of circulating glucose are likely a result of the structure the carbohydrate source in formulated feeds and stimulate the deposition of glycogen through the allosteric control of glycogen synthase. Formulated feeds produced higher cooked meat yields in canning simulation trials, suggesting that muscle glycogen content may indirectly play a role in increasing canning yields through the displacement of collagen. The results of these empirical studies are synthesised under key themes, discussed within the context of their potential commercial relevance and future research directions are highlighted.
- Full Text:
- Date Issued: 2018