Synthesis, characterization and host-guest complexes of supramolecular assemblies based on calixarenes and cucurbiturils
- Authors: Baa, Ebenezer
- Date: 2022-10-14
- Subjects: Supramolecular chemistry , Calixarenes , Cucurbiturils , Metal-organic frameworks , Macrocyclic compounds , Drug delivery systems
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/365621 , vital:65765 , DOI https://doi.org/10.21504/10962/365621
- Description: The field of supramolecular chemistry has grown large and wide in both deepness of understanding, range of topics covered and scope and applications. Supramolecular self-assemblies are facilitated by a wide range of non-covalent intra and inter molecular interactions that range from hydrogen bonding to π-interaction and van der Waals. Macrocyclic compounds such as cucurbiturils and calixarenes have emerged as important classes of compounds with excellent potential of forming supramolecular assemblies. The porous nature of these compounds enables them to form host-guest supramolecular complexes stabilized by diverse range of non-covalent interactions. Furthermore, these compounds contain donor atoms capable of forming bonds with metal ions to yield metal complexes with interesting porous characteristics that deviate from their traditional hydrophobic cavity. The versatile nature of the resulting pores imply that they can accommodate diverse types of guests. This work explores the synthesis and characterization of a host of calixarenes and cucurbiturils. Self-assembly of these macrocycles with various metal ions results to the formation of porous metal organic framework (MOF) complexes. Four new calixarene typed compounds obtained from aromatic aldehydes and twenty-six cucurbituril metal complexes are reported. These macrocylces and their metal complexes also form supramolecular complexes with DMSO, methanol, isoniazid hydrochloride and ciprofloxacin hydrochlorides through either self-assembly, mechanochemistry and exposure to solvent vapors. The bulk materials have been characterized using nuclear magnetic resonance spectroscopy (NMR), Fourier transformed infrared spectroscopy (FTIR), powder and single crystal diffraction techniques and thermal studies thermogravimetric analysis (TGA) and differential thermal calorimetry (DSC). Data obtained from this study reveals that calixarenes can form supramolecular complexes with a frequently used laboratory solvents with BN22 showing appreciable selectivity for DMSO sorption from a solvent mixture. These compounds also form supramolecular complexes with drug molecules such as isoniazid and ciprofloxacin. Furthermore, the data reveals that choice of synthetic route of supramolecular ensembles dictates if the guest drug molecule will occupy the intrinsic or extrinsic pores of cucurbituril complexes. Biological studies on the obtained complexes reveal that the cucurbituril complexes are non-cytotoxic while the calixarenes show antibacterial activity against Escherichia coli and Staphylococcus aureus. Additionally, the study showed that ciprofloxacin can be successfully released from a calixarene host in a simulated body fluid although the host was also found to cross the dialysis membrane. The results of this study are important in that; - they can be exploited and developed in the selective sorption of certain guests and - that they can be used in the development of drug delivery systems that play a dual role of delivery and therapeutic activity. , Thesis (PhD) -- Faculty of Science, Chemistry, 2022
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Synthesis, In-Silico molecular modelling and biological studies of 1,4-Dihydroxyanthraquinone and its derivatives
- Authors: Kisula, Lydia Mboje
- Date: 2022-10-14
- Subjects: Computer simulation , Molecules Models , Dihydroxyanthraquinone , Trypanosomiasis , Leishmaniasis , Docking
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/365828 , vital:65793 , DOI https://doi.org/10.21504/10962/365828
- Description: This current study of investigation reports on the synthesis of 1,4-dihydroxyanthraquinone and its derivatives on explorations of their medicinal potential. The study initially aimed to synthesize an analogue of a natural anthraquinone, 1,3,6-trihydroxy-7-((S)-1- hydroxyethyl)anthracene-9,10-dione 5 using Friedel-Crafts acylation of phthalic anhydride and a benzene derivative. Synthetic transformation of anacardic acid 63, obtained as a by- product of the cashew industry successfully afforded 4-ethoxyisobenzofuran-1,3-dione 89. However, when attempted to couple 4-ethoxyisobenzofuran-1,3-dione 89 with 2- hydroxyacetophenone 91 in a Friedel-Crafts acylation manner to form 2-acetyl-1,8- dihydroxyanthracene-9,10-dione 87 the reaction did not work efficiently. A simple derivative of benzene which is; benzene-1,4-diol 102 was reacted instead with 3-ethoxyphthalic acid 71 and isobenzofuran-1,3-dione 96 to form 1,4,5-trihydroxy anthraquinone 72 and 1,4- dihydroxyanthraquinone 42, respectively. A modified Marschalk reaction was then used to introduce the hydroxyl alkyl group to 1,4-dihydroxy anthraquinone 42, which allowed further elaboration of the hydroxyl-substituent in moderate to good yields (22-80%). A molecular docking study was performed using Schrödinger software to predict the binding affinity of the test compounds to the target protein trypanothione reductase (PDB ID: 6BU7). An in-vitro screening of 1,4-dihydroxyanthraquinone derivatives and some selected precursors for antitrypanosomal, antiplasmodial, antibacterial, and cytotoxicity activities produced encouraging results. Derivatives of anacardic acid and cardanol from CNSL were found to have moderate activity against trypanosomes with no activity against Plasmodium falciparum. Almost 63% of synthesized 1,4-dihydroxyanthraquinone derivatives displayed activity against trypanosomes. The in-vitro evaluation and the in silico molecular docking studies revealed that 1,4-dihydroxyanthraquinone derivatives can be potential drug-like candidates active against T.brucei parasites (IC50 = 0.70-1.20 μM). Only four 1,4- iv dihydroxyanthraquinone derivatives with thiosemicarbazone, chloride, pyrrole, and diethanolamine functionality displayed activity against Plasmodium falciparum (IC50 = 3.17- 14.36 μM). In-vitro evaluated of test compounds against antibacterial screen and cytotoxicity effects significantly showed that 2-hydroxy-6-pentadecylbenzoic acid 63a and 2-((2- chlorophenyl)(piperazin-1-yl) methyl)-1,4-dihydroxyanthracene-9,10-dione 78 have potency against Staphylococcus aureus and reduced the viability of the cells below 20% at an initial concentration of 50 μg/mL. Only 1,4-dihydroxyanthraquinone derivatives with thiosemicarbazone 76, piperazine 78, and diethanolamine 80 motifs were active against HeLa cells and reduced the viability of cells below 20% at a concentration of 50 μg/mL. In conclusion, this current reported study has generated useful knowlege on the applicability of the agro-waste CNSL as an agent active against trypanosomiasis but also as a low-cost starting material to synthesize hydroxy anthraquinones. The study has further given an overview to the understanding of the medicinal value 1,4-dihydroxyanthraquinone derivatives as promising candidates towards developing drugs suitable for treating neglected tropical diseases particularly trypanosomiasis. , Thesis (PhD) -- Faculty of Science, Chemistry, 2022
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Teachers’ knowledge and practice in Grade 3 Group Guided Reading: a case study
- Authors: Kitsili, Ntsikohlanga Anthony
- Date: 2022-10-14
- Subjects: Reading (Elementary) , Guided reading , Group reading , Teaching practices
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405270 , vital:70156
- Description: Group guided reading (GGR) was introduced as part of the Curriculum and Assessment Policy Statement (CAPS) in 2012, but it appears that teachers are still experiencing great difficulty in teaching it (Hoadley 2018). Several interventions have been designed across South Africa to support teachers in no-fee schools to improve the teaching of reading. The evaluations of such interventions show that teachers receiving support such as coaching are able to master the procedural aspects of GGR but not the conceptual aspects, for example, teaching comprehension strategies and providing formative assessment (Fleisch & Dixon, 2019; Hoadley, 2017). The research reported in this thesis aimed to find out what kinds of knowledge are required to teach GGR and to what extent teachers enact this knowledge in their practice, using Shulman’s (1987) knowledge categories: subject content, pedagogical content and curriculum knowledge, general pedagogical knowledge and strategic knowledge. The research took the form of an interpretivist case study focusing on three Grade 3 teachers using GGR to teach reading in their classrooms. It was carried out in three no-fee, township schools where isiXhosa is the language of learning and teaching. Data was generated through observations, stimulated recall interviews, semi-structured interviews and document analysis. There are two policy documents that guide teachers’ practices in terms of how they should teach reading during GGR and that give clear guidance on what children should learn during GGR: the Foundation Phase CAPS and the National Framework for the Teaching of Reading in African Languages in the Foundation Phase. These documents were analysed using Shulman’s (1987) knowledge categories. Transcripts of teachers’ reflections on their GGR lessons during stimulated recall interviews were read hand in hand with transcripts of the GGR lessons that were video and audio recorded, and these were analysed using Shulman’s knowledge categories. The findings of the research are that teachers’ subject content knowledge is largely tacit; it is knowledge-in-practice. The teachers in the study seemed confident in showing rather than explaining what it is that they are doing and why they are doing it. All three teachers have mastered, to a large extent, the procedural aspects of GGR and some of the more conceptual aspects, for example some aspects of fluency, the teaching of decoding strategies and formative assessment. However, there was limited evidence of the teaching of comprehension strategies and the use of higher order questions, and assessment was not evident in the recorded lessons. , Ukufunda ngokwamaqela kusetyenziswe njengenxalenye yoluhlu lwezifundo kunye novavanyo mgaqo nkqubo lexwebhuCurriculum and Assessment Policy Statement (CAPS) lonyaka ka 2012, kodwa kubonakala ukuba ootitshala basatsala nzima ukusifundisa esisifundo (Hoadley 2018). Aliqela amaphulo aye ayilwa eMzantsi Afrika jikelele ngeenzame zokuxhasa ootitshala abafundisa kwizikolo zafelefele ukuba baphuhle kwisakhono sokufundisa ukufunda. Iziphumo zovavanyo zalamaphulo zibonakalise ukuba ootitshala abafumana inkxaso ekukuqeqeshwa baye bagqwesa ekufundiseni indlela ezilandelwayo ekufundiseni ukufunda ngokwamaqela, kodwa isengumcelamngeni ukufundisa izakhono eziphuhlisa ukufunda ngengqiqo nokuhlola inkqubela yabafundi ekufundeni, (Fleisch & Dixon, 2019; Hoadley, 2017). Ingxelo yophando lwale tyhisisi - belujole ekuboniseni ukuba loluphi ulwazi ekumele ootitshala babenalo ekufundiseni ukufunda ngokwamaqela, kwaye olulwazi lungancedisana njani nootitshala ekufundiseni ukufunda, ndisebenzisa iindidi zolwazi eziqulunqwe nguShulmna (1987): ulwazi ngomxholo wesosifundo, ulwazi ngeendlela ezifanelekileyo zokufundisa esosifundo kunye nolwazi oluqulathwe kuluhlu lwezifundo (curriculum), ulwazi oluphangaleleyo noluquka iindlela ezifanelekileyo zokufundisa, kunye nolwazi malunga namaqhinga athile ancedisana nokufundisa ukufunda ngendlela efanelekileyo. Oluphando lulandele indlela yokuphanda ebizwa ngokuba yi interpretivist case study ngokolwimi lwase mzini, eyona nto esisifundo besigqale kuyo ibi ngootitshala abathathu bebanga lesithathu abafundisa ukufunda kubantwana bengamaqela kumagumbi wabo okufundela. Oluphando luqhutyelwe kwizikolo ezintathu zafelefele (zikaRhulumente) elokishini apho isiXhosa ilulwimi olusetyenziswayo ekufundiseni nasekufundeni. Iinkukacha ziqokelelwe ngoku qwalasela okuqhubekayo egumbini lokufundela, nangokwenza uviwano ndlebe oluzindlela ezimbini: olokuqala lwenziwe emveni kwesifundo, ze olwesibini lwaqhutywa emveni kwesikolo apho utitshala uye wabukela umfanekiso oshicelelweyo wesifundo asiqhubileyo aze ahlatywe imibuzo ngesosifundo asijongileyo, kunye nangoku hlalutya okuqulathiweyo kumaxwebhu afana no CAPS. Mabini amaxwebhu aqulathe umgaqo nkqubo ochazela ootitshala ukuba mabakufundise njani ukufunda ngelixa abantwana befunda bengamaqela, kwaye angumkhombandlela ochaza gca okulindeleke abantwana bakufude ngexesha lokufunda bengamaqela: the Foundation Phase CAPS and the National Framework for the Teaching of Reading in African Languages in the Foundation Phase. Lamaxwebhu ahlalutywe ngokulandela iindidi zolwazi zika Shulmna (1987). Imibhalo ekhutshelweyo (transcripts) enika ingxelo ngokucingwa ngootitshala ngomsebenzi wabo wokufundisa abantwana bengamaqela ngexesha loviwano ndlebe ifundwe ngaxesha nye nemibhalo ekhutshelweyo yokufundiswa kwabantwana bengamaqela ebishicelelwe yangumboniso bhanyabhanya kunye nophulaphulekayo, oku kuye kwahlalutywa ngokusebenzisa iindidi zolwazi zika Shulman (1987). Iziphumo zophando zibonakalise ukuba ulwazi lootitshala malunga nomxholo wezifundo alubonakali ngokuthe gca, lubonakale ilulwazi olubonakala ngezenzo. Ootitshala abathathe inxaxheba kwesisifundo babonakale bezithembile ekuboniseni indlela abaqhuba ngayo, kodwa basilela ukucacisa ngokwamazwi abo into abayenzayo okanye unobangela wokwenza ngandlela ithile. Bonke ootisthala abathathu bagqwesile ekuboniseni ukuba bayayazi imigaqo ekufuneka ilandelwe xa kufundiswa isifunda samaqela ngamaqela, kwaye babonisile ukuba banalo ulwazi lokuphuhlisa izakhono zokufunda ngokutyibilika, nokufundisa abantwana amaqhinga athile abanowasebenzisa xabeguqula okufihlakele entethweni, kunye nendlela ezisesikweni zokuhlola. Nangona kunjalo nje ubungqina obubonisa ukuba abatitshala bathathu banaso isakhono sokufundisa amaqhinga okufunda ngengqiqo, kunye nokubuza imibuzo ekwinqanaba eliphezulu, kwaye namaxwebhu abonisa uhlolo luka titshala bunqongophele. , Thesis (MEd) -- Faculty of Education, Education, 2022
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Teachers’ narratives of their experience of teaching Fetal Alcohol Spectrum Disorders (FASD) -affected children in mainstream schooling
- Authors: Makasi-Simukonda, Mihlali
- Date: 2022-10-14
- Subjects: Fetal alcohol spectrum disorders South Africa Buffalo City , Inclusive education South Africa Buffalo City , Teachers of children with disabilities South Africa Buffalo City , Children of prenatal alcohol abuse South Africa Buffalo City Social conditions , Social constructionism
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406183 , vital:70246
- Description: This study considers the experiences of teachers working with Fetal Alcohol Spectrum Disorders (FASD)-affected children in mainstream schooling. FASD refers to a range of conditions in children resulting from maternal alcohol consumption during pregnancy. Prevalence rates in South Africa are said to be among the highest in the world. There is a paucity of research on FASD-affected children in the Eastern Cape. This study was thus conducted in the Buffalo City Metropolitan Municipality (BCMM). Teachers told stories of their experiences of teaching undiagnosed FASD-affected children in mainstream schooling. The stories reveal the quality of life for children in classrooms and socio-contextual influences of their experiences at school, as well as the responsibilisation of teachers in these settings. This qualitative research is situated within a social constructionism paradigm. The social model of disability was utilised as a theoretical framework for this study to represent the systemic barriers against which FASD-affected learner support in the mainstream school can be conceptualised. A sample of five (5) Black female teachers were interviewed. Data gathering was done by conducting telephonic interviews using the single question inducing narrative, known as SQUIN. A thematic analysis of the data was conducted for the purpose of identifying themes within the data collected. Four superordinate themes emerged from the data, viz. narratives of FASD-affected learners, narratives of parental involvement, narratives of the role of teachers and narratives of stakeholder support. This study reveals a significant level of responsibilisation of teachers. Teachers appear to play a bigger role than just being teachers and they positioned themselves as playing a parental role in relation to FASD-affected learners. FASD-affected learners were positioned as “the problem” in the mainstream classroom whereas the environment is a disabling factor to FASD-affected learners. There is a need for a holistic approach in working with FASD-affected learners from all relevant stakeholders. Key recommendations are made for effective inclusion of FASD-affected learners in mainstream schooling. Future research recommendations include repeating this study in a different geographical area, a focus on senior phase learners and/or a more diverse sample. The findings assist in the development of policies of inclusive education in mainstream schooling and supportive strategies to enhance the developmental trajectory of FASD-affected children. , Thesis (MA) -- Faculty of Humanities, Psychology, 2022
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Teachers’ practice in developing visually impaired learners’ reading skills in the junior primary phase in northern Namibia
- Authors: Nuugonya, Elizabeth Nangula
- Date: 2022-10-14
- Subjects: Children with visual disabilities Education Namibia Oshana , Reading (Elementary) Namibia Oshana , Inclusive education Namibia Oshana , Convention on the Rights of Persons with Disabilities and Optional Protocol (2007 March 30) , Braille Study and teaching (Elementary) Namibia Oshana , Teachers of the blind Namibia Oshana
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405379 , vital:70166
- Description: Namibia has adopted, ratified and followed several international policies on disability and inclusive education including the United Nations Convention on the Rights of Persons with Disabilities (UNCRPD). Since 2014, the Namibian education system has been working towards the implementation of the Sector Policy on Inclusive Education to promote an education system that is accessible, inclusive, equitable and of good quality (Namibia. Ministry of Education, Arts and Culture: Sector Policy on Inclusive Education, 2013). The policy aims to address barriers faced by learners with disabilities and how teachers develop ways of teaching that respond to the individual differences. Reading in a second language tends to develop more slowly by visually impaired learners, although the Junior Primary Phase syllabus promotes equal opportunity for all learners to participate in reading equally irrespective of learners’ disabilities. Teachers should understand how to teach and accommodate learners who are visually impaired and all reading materials should be fit for purpose and support these learners appropriately. Thus, this study explores how Junior Primary teachers develop visually impaired learners’ reading skills to provide accessible education to them. Learning to read is challenging for most learners, but even more for learners who are visually impaired. Learning to read braille is a complex process, far more than reading print texts. This study seeks to examine how learners are taught to read using braille in a school for visually impaired learners in Namibia, Oshana region. The motivation for this research study was twofold - firstly, my interest in the development of reading skills with visually impaired learners was aroused by my teaching experience. Secondly, due to my realisation that the area was under-researched in Namibia; I wanted to fill the existing gap in the development of reading skills in braille and print. The study critically engaged teachers to help me obtain an understanding of how they develop reading instructions with visually impaired learners and the factors that enabled the development of braille literacy and the challenges that hampered the development of reading skills. The study took the qualitative case study approach underpinned by an interpretivist orientation. Data was collected using semi-structured observation during reading lessons and focus group interviews. The Theory of Practice Architectures (ToPA) was used as a lens to analyse the promoting and constraining factors in teaching visually impaired learners reading skills. The study found that teachers used different reading methods to promote the development of reading skills such as reading aloud, tactile methods and phonics. The study further noted that teachers mostly created their own reading materials due to the lack of reading materials and reading books printed in braille. Although learners were supported during reading, the challenge of developing reading skills with visually impaired learners remains a challenge. I hope that the findings from this research study strengthen the development of reading skills in all special schools and contribute to the creation of knowledge on the development of reading skills with visually impaired learners in Namibia. As a means to further support learners who experience visual impairments, this study recommends that more formative research studies on the notion of teachers’ practice in developing reading skills with visually impaired learners should be conducted to bring about change. , Thesis (MEd) -- Faculty of Education, Education, 2022
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Teaching in times of crisis: understanding the uneven effects of the COVID-19 lockdowns on teaching practices in Zimbabwe – a case study of Marondera
- Authors: Nhliziyo, Sarah Mazvita
- Date: 2022-10-14
- Subjects: COVID-19 Pandemic, 2020- Zimbabwe , Lockdown , Social distancing (Public health) and education Zimbabwe , Educational equalization Zimbabwe , COVID-19 Pandemic, 2020- Economic aspects , Teaching Social aspects Zimbabwe
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/408682 , vital:70516
- Description: The COVID-19 pandemic has exposed the fragility of economies in times of a global crisis while simultaneously increasing inequalities between and within countries. The pandemic responses have varied between countries with some being extremely proactive and others being quite reluctant to respond. Though it is largely a health crisis, its impact has far reaching effects that have been felt in many sectors of society including education. Billions of scholars at varying levels were forced out of school abruptly globally and unfortunately some have not been able to return to schools. The differential impact of COVID-19 in education is evident not only at a global level, but national level as well. The primary focus of this research is the impact of COVID-19 on the teaching practices applied in Zimbabwean schools. Zimbabwe, a developing nation in the southern region of Africa, has a long history of a thriving education sector recognised internationally. However, in the wake of the pandemic, the research attempts to understand the experiences of teachers in private and government schools in the hope of showing the dilapidation and unevenness of the sector, across the private-public divide. COVID-19 comes at a time when the country’s economy and healthcare system continue to exhibit signs of struggle and collapse. The research made use of qualitative research methods and in-depth interviews with teachers from public and schools around the town of Marondera. The research concluded that there are wide gaps in the quality of education delivered to students in private and government schools, and that the COVID-19 lockdowns in Zimbabwe not only demonstrate these gaps but also exacerbated them. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2022
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The 2019 SASBO Bank Workers’ Strike in South Africa: unpacking labour responses to the Fourth Industrial Revolution
- Authors: Moyo, Wisdom Ntandoyenkosi
- Date: 2022-10-14
- Subjects: Industry 4.0 , Fourth Industrial Revolution , Banks and banking South Africa , SASBO , Labor unions South Africa , Strikes and lockouts Bank employees South Africa , Working class South Africa
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406774 , vital:70306
- Description: The Fourth Industrial Revolution (4IR) is a global phenomenon, affecting workers and trade unions worldwide with the increased automation, including digitisation, of work. Although the 4IR has often been presented as an impersonal technological force that society must just accept, it is in fact rooted in the evolution of capitalist society: it is the latest in a series of industrial revolutions and restructurings of the labour process. These are systemic occurrences, based in class struggles around the extension of management control of every part of work, and replacing workers with machinery; it must then be seen in the context of a history of Taylorism, Fordism and neo-Fordism, and their local expressions, such as racial Fordism in South Africa. The roll-out and the socio-economic effects of the 4IR are therefore shaped by inequality and power, and look to be dire for the working-class in a South Africa that already has record unemployment rates. In the local banking sector, the 4IR has been associated with a wave of retrenchments and branch closures. Faced with this situation, the South African Society of Bank Officials (SASBO), the biggest and oldest union in the finance sector, then with around 73 000 members, tried to hold a mass strike in late 2019. Blocked by the Labour Court, this would have been the union’s biggest strike in a century. It followed from a longer campaign by SASBO to halt job losses, ensure redeployment and reskilling for affected bank workers, and win an agreement for these aims with the banks. The union undertook research on the 4IR and sought to win support from banks, as well as government departments and other unions, for an alternative, worker-friendly roll-out of the 4IR. The decision to strike took place after extensive engagements with banks and stakeholders like government failed, the banks proceeding with retrenchments: the union faced an unprecedented challenge and was on the defensive. This dissertation maps SASBO’s campaign around the 4IR, using the Power Resources Approach (PRA), and assesses its approach. It also tries to show how an analysis of a moderate, older white-collar union like SASBO enriches South African labour studies. A qualitative methodology was used in this research to understand the issue at hand, using documents and semi-structured interviews with SASBO National Executive Committee members. The key findings are that the 4IR will not spare white-collar jobs and presents an unprecedented challenge to unions. There is an urgent need for union revitalisation, including new ways to organise effective responses to technological change. , Thesis (MA) -- Faculty of Humanities, Sociology, 2022
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The biology of Oreochromis mossambicus and vulnerability to the invasion of Oreochromis niloticus
- Authors: Mpanza, Nobuhle Phumzile
- Date: 2022-10-14
- Subjects: Ecomorphology , Mozambique tilapia , Nile tilapia , Introduced fishes , Predatory aquatic animals , Predation (Biology) , Otoliths , Von Bertalanffy function
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362983 , vital:65380
- Description: Mozambique tilapia, Oreochromis mossambicus, a native southern African species now co-occurs with invasive Nile tilapia, Oreochromis niloticus throughout much of the distribution of the former. The spread of O. niloticus in South Africa has been attributed to escapees from aquaculture facilities, placing O. mossambicus at risk through competition for habitat and food resources, as well as through hybridisation. To better manage invasions, a comprehensive understanding of the biology, ecology and behaviour of both native and invasive species is required. The aim of this research was to comparatively assess the biology of O. mossambicus and O. niloticus, their food resource use characteristics and potential competitive interactions to infer impact risks associated with O. niloticus invasion dynamics. In addition to lack of sufficient autecological knowledge on O. niloticus in general, the challenge in the Eastern Cape is that relatively little regional knowledge is available on the biology and ecology of the native O. mossambicus. To address this, a total of 101 O. mossambicus individuals (32 - 297 mm LT) were sampled from the Sunday River catchment and their age and growth determined using sectioned sagittal otoliths. The largest female was 288.8 mm with a parameter estimate of LT (mm) = 272 (1-e-0.331(t=0.772)) and the largest male was 297 mm described as LT (mm) = 331.9 (1-e-0.167(t=1.192)). The growth parameter estimate age for combined sexes was best described as LT (mm) = 322.5 (1-e-0.201(t=1.027)). The growth rate was initially rapid for O. mossambicus and the asymptotic length reached after four years. The length-at-50% maturity was reached at 106.45 mm LT (R2 = 0.57) for the entire population. There was a significant difference (ᵡ2 = 8,047, df = 1, p-value = 0.0045) in the sex ratio between males and females which was skewed towards males 1:1.89 (F:M). Comparisons with O. niloticus were based on literature and these showed that O. niloticus had faster growth rates than O. mossambicus. These results serve as a baseline study in predicting the potential impacts of O. niloticus if it was to be introduced in the Eastern Cape region. Furthermore, although these two species are known to share habitat and food resources, feeding dynamics within the context of relative impact on prey resources, and competition potential between the species, are largely lacking. I used experimental functional response procedures to contrast the food consumption dynamics of each species and to assess for any multiple predator effects (MPEs) between these two closely related fishes. This was done by contrasting functional responses between individual species under single predator scenarios, predicted multiple predator functional response dynamics based on the individual species outputs, and actually observed functional responses under multiple predator conditions. Results showed that both Nile tilapia and Mozambique tilapia depicted a destabilizing Type II functional response. In both single and conspecific pairing Nile tilapia had significantly greater functional responses than Mozambique tilapia, hence greater overall predatory potential than its native congeneric Mozambique tilapia. Attack rates were also greater for Nile tilapia than Mozambique tilapia with both species showing similar handling times in single trials. However, no evidence for MPEs were detected, given lack of differences between predicted and observed functional responses under heterospecific conditions. These results suggest that Nile tilapia do not adjust their food intake in the presence of heterospecific competitors, but do consume more than Mozambique tilapia and are better at finding food when it is present at low densities. Feeding-related morphological characteristics may influence predatory performance of a species and can further provide information on the species’ capacity to locate, attack and consume different prey items. The feeding capacities between O. mossambicus and O. niloticus were compared based on morphological traits in order to determine whether differences existed, and if these differences place the invasive O. niloticus at an advantageous position in terms of resource acquisition and consumption over its native congener. Principal component analysis for functional morphology traits showed overlap between O. niloticus and O. mossambicus. Oreochromis niloticus had distinctively larger lower jaw closing force, gill resistance and gill raker length which facilitated greater feeding capacities for the invasive species over the native O. mossambicus. Trophic profiles depicted high dietary overlap between the two species. Although O. niloticus had a greater feeding capacity towards phytoplankton, plants, fish (ambush), fish (pursuit) and larvae, while O. mossambicus only showed greater feeding capacity towards zooplankton. While dietary overlap and similarities in morphological traits between native and invasive species may result in exploitative competition between the species, O. niloticus seems to be more versatile in its feeding and capable of consuming food web components that O. mossambicus may not be able to handle. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2022
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The Daily Sun subscribers
- Authors: Mahe, Xolani
- Date: 2022-10-14
- Subjects: Creative writing (Higher education) South Africa , Diaries -- Authorship , Books Reviews , South African fiction (English) 21st century , Short stories, South African (English) 21st century
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406276 , vital:70254
- Description: My thesis comprises interlinked short stories, verfabula, sketches, fragments, flash fiction, folktales, anecdotes, and the epistolary form. I write in English tinged with IsiXhosa. In terms of specific influences, the collection is strongly influenced by the experimental writing of Kathy Acker and Samuel Delany notably the uncompromising ways in which they contort formal grammar and sexuality, the defamiliarizing function of the phantasmagoria in the films of Alejandro Jodorowsky and David Lynch, the techniques of the picturesque as used by Amos Tutuola, and, importantly, narration in the present tense as deployed in Dambudzo Marechera’s House of Hunger which results in negation and subversion of the narrative depiction of the past, the present, and the future. On the stylistic level, I am strongly influenced by the haunting surrealism of Sony Labou Tansi, the eccentric meditations of Julio Cortázar, and the iconoclastic rants of Lesego Rampolokeng. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
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The development of a novel plant-based biomaterial scaffold for tissue engineering applications
- Authors: Mamphey, Maame Nicole
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/365223 , vital:65718
- Description: Thesis embargoed. Possible release date set for early 2025. , Thesis (MSc) -- Faculty of Science, Biotechnology Innovation Centre, 2022
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The development of teachers’ pedagogical content knowledge (PCK) in the mediation of chemical equilibrium: A formative interventionist study
- Authors: Manamike, Tasara
- Date: 2022-10-14
- Subjects: Chemical equilibrium , Chemistry Study and teaching (Secondary) Nambia , Expansive learning , Career development Nambia , Professional learning communities Nambia , Pedagogical content knowledge , Cultural-historical activity theory
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405300 , vital:70159
- Description: Persistent student errors in understanding chemical equilibrium as shown by poor student achievement in national examinations reflect student difficulties in learning and deficiencies in teaching methodologies. Studies which have been conducted in Namibia have explored the teaching of chemical equilibrium and revealed that teachers seem not to have adequate pedagogical content knowledge (PCK) for mediating chemical equilibrium and therefore there is a need for continuing professional development (CPD). However, it seems the CPD facilitators also find this topic difficult and are unsure of which methods are really effective owing to the disagreements among teachers and researchers. In addition, current CPD practices ostensibly fail to address the teachers’ needs because the facilitators have their own commitments and accountabilities and may ignore teachers’ contexts. It is against this backdrop that I conducted this formative interventionist study to improve teachers’ PCK for mediating chemical equilibrium through expansive learning (learning something that does not yet exist). A blend of the interpretivist and critical paradigm underpinned this study, which assumed a transactional epistemology. The qualitative case study research design was used to gather in-depth information about the multiple realities of the participants, bearing in mind that teaching is idiosyncratic, and the teaching approaches or strategies employed heavily depend on the contexts. Accordingly, the cultural historical activity theory was used to guide the teachers’ activities during the intervention for generating the data which were analysed using the topic-specific pedagogical content knowledge. The study revealed that the participants faced challenges in their teaching, namely: (i) students’ difficulties with comprehension and (ii) teachers’ instructional problems or deficiencies in instructional skills. The findings also revealed that the intervention enabled the participants to collectively transform their practices and therefore address the major challenges in their practices, that is, they expansively learnt how to effectively teach chemical equilibrium. , Thesis (MEd) -- Faculty of Education, Education, 2022
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The development, formulation and characterization of an optimized metronidazole loaded solid lipid nanoparticle formulation for ocular drug delivery
- Authors: Sikhondze, Simise Siphelele
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/403014 , vital:69914
- Description: Thesis embargoed. To be released early 2026. , Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2023
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The distribution and perceptions of invasive alien plants in small towns in the Eastern Cape province, South Africa
- Authors: Seboko, Tshepiso Collen
- Date: 2022-10-14
- Subjects: Invasive plants South Africa Eastern Cape , Land use South Africa Eastern Cape , Invasive plants Control South Africa Eastern Cape , Public opinion South Africa Eastern Cape , Urban ecology (Biology) South Africa Eastern Cape
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/${Handle} , vital:65669
- Description: Invasive alien plants (IAP) of different life forms have major effects on biodiversity, ecosystem functioning, economies, and livelihoods worldwide. There is evidence that IAP are rapidly increasing around the world, and the negative impacts associated with them are expected to worsen due to continuing land transformation, climate change, and urbanisation. Yet, information on the distribution, abundance, knowledge, and perceptions of IAP is limited, especially in small towns. Most previous research has largely focused on rural settings and larger cities, thus hindering the effective control and management of IAP in smaller urban settings. It is therefore important to assess the distribution of IAP to provide useful information to guide clearing and mitigation efforts to reduce the impacts and proliferation of IAP in smaller urban settings. Consequently, the aim of the study was to determine the distribution, composition, abundance, and perceptions of woody IAP in small towns in the Eastern Cape province of South Africa and assess how and why they may differ within and between towns. To achieve this aim, a drive by road survey was undertaken across all suburbs and land use types in 12 small towns located in the Eastern Cape province of South Africa. The 12 randomly selected small towns were, Adelaide, Alexandria, Barkley East, Bedford, Burgersdorp, Cathcart, Kirkwood, Middelburg, Paterson, Somerset East, St. Francis Bay and Willowmore. All woody IAP visible from the surveyed roads were counted across all suburbs and land use types within each town. A total of 38 427 woody IAP were enumerated, with 56 species across different land use types and suburbs in all towns. Affluent suburbs accounted for 58% of the IAP enumerated, while the Reconstructed Development Programme (RDP) suburbs accounted for only 5%. In terms of the land use type, most of the IAP were encountered in the residential areas (54%), as compared to, road verges (32%) and public urban green spaces (PUGS) (14%). Of the 12 towns, Middleburg had the highest number of woody IAP, with 5 573 individuals, while Paterson had the lowest number with 947. The most common IAP species across all towns was Melia azedarach with 4 384 individuals, followed by Pinus elliotti (4 051), and Jacaranda mimosifolia (3 640). Spathodea campanulata, Ardisia crenata, and Parkinsonia aculeata had the lowest number of individuals with only two individuals each across all towns. This study also assessed the knowledge, perceptions, and willingness of urban residents to control IAP in their home yards using household surveys. A total of 240 household surveys were administered in the 12 towns. The results showed that more than half of the respondents (59%) had no knowledge of IAP, while 14% had neutral knowledge and only 2% had high knowledge. Forty percent of the respondents agreed that IAP pose a problem to the environment whilst 11% did not think IAP posed a problem to the environment, and 49% stated that they do not know. Most of the respondents (91%) perceived IAP positively, and stated that they benefit from the IAP, with the most mentioned benefit being shade (50%). Almost two-thirds of the respondents (65%) were willing to report on the IAP in their yards to the relevant authorities that deal with the control and management of IAP. Over half (56%) of the respondents were willing to have the IAP removed from their gardens, with the most stated reason for removal was because the IAP caused damage to property (13%). Respondents thought that the local government (35%) or district government (30%) should be responsible for the control and management of IAP. Overall, the study showed that IAP species were most common in residential land use type and affluent suburbs. These findings can assist the relevant authorities that deal with IAP, regarding which plant species, suburbs, and land use types to prioritise regarding awareness and investment for control and management. This will also help explore alternative indigenous species that can be used as replacements that may offer the same benefits derived from IAP by urban residents. , Thesis (MSc) -- Faculty of Science, Environmental Science, 2022
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The effect of orchard sanitation and predatory ants on the eclosion of the internal feeding pests and Oriental fruit fly, in South Africa
- Authors: Makitla, Tshepang
- Date: 2022-10-14
- Subjects: Orchards South Africa , Phytosanitation , Citrus Diseases and pests Biological control , Ants , Insects as biological pest control agents
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362927 , vital:65375
- Description: There are several pests of phytosanitary concern in the citrus industry in South Africa. Orchard sanitation can play an important role in suppressing the populations of these pests, however there are little data on the efficacy of sanitation techniques. Therefore, the current study investigated the effect of fruit disposal techniques and burying depths on the eclosion of the most important pests of citrus in South Africa, false codling moth Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae), Mediterranean fruit fly or Medfly Ceratitis capitata Wiedemann (Diptera: Tephritidae), Natal fruit fly Ceratitis rosa Karsh (Diptera: Tephritidae), and Oriental fruit fly Bactrocera dorsalis Hendel (Diptera: Tephritidae). Abscised C. sinensis fruits were inoculated with larvae of T. leucotreta, and eggs of C. capitata, C. rosa, and B. dorsalis, before being disposed as pulped, or whole, and buried at different depths (0 cm, 5 cm, 25 cm, and 50 cm). Abundance and richness of predatory ants were monitored using pitfall traps to ascertain their effect on the mortality of the immature stages of these pests. Ceratitis capitata and C. rosa failed to eclose from the inoculated fruits disposed at different depths, however, T. leucotreta and B. dorsalis adults did eclosed. Significantly fewer B. dorsalis eclosed from fruits that were pulped in comparison to eclosion where the fruit were left whole (F (3, 16) = 11.45, P < 0.01). Furthermore, depth of burial had a significant effect on the number of eclosed adults of Drosophila sp (F (3, 112) = 3.43, P < 0.01). Burying fruits at 50 cm suppressed the eclosion of all the internal feeding pests tested. Twenty-seven thousand seventy-three individual ants (Hymenoptera: Formicidae) were sampled from the same plots as used above, with at least 47% and 53% sampled from plots where pulped and whole C. sinensis fruits were disposed of, respectively. The ants were identified to morphospecies which included Pheidole1, Pheidole2, Formicinae1, Formicinae2, Formicinae3, and Myrmicinae1. The disposal of the inoculated C. sinensis fruits either as pulped or whole and burying at different depths significantly suppressed and/or delayed the eclosion of either of the tested internal feeding pests of citrus. Although, predacious ants were sampled from the same treatment plots they did not affect the survival or eclosion of the tested pests, and this could be attributed to the application of the slow toxic ant bait. Therefore, based on the observed results B. dorsalis adults showed the ability to eclose from 50 cm depth where fruit was either disposed as pulped or whole, thus, citrus farmers are advised to use hammer mill that will finely crush sanitised fruit, and/or bury fruit beyond 50 cm depth to prevent the adult od this pest from eclosing. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2022
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The effects of strategic planning and oversight on electricity service delivery outcomes in South African local municipalities: a case study of Inxuba Yethemba Municipality
- Authors: Ntintili, Noxolo Indwe
- Date: 2022-10-14
- Subjects: Strategic planning South Africa , Strategic management , Municipal services South Africa , Local government South Africa , Local service delivery , Public sector , Oversight
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/408693 , vital:70517
- Description: Poor service delivery in South Africa is a widely researched phenomenon. Yet despite the existing knowledge production efforts, in a context of a progressive developmental municipal legislative framework, South African municipalities continue to be plagued with corruption and poor service delivery performance. This thesis aims to transcend the tendency to attribute poor service delivery to a sole cause (e.g. corruption) by explaining the effects of strategic planning and oversight on several municipal service delivery processes. Therefore, this thesis introduces the Municipal Public Resource Management (MPRM) model as a strategic management tool to explain the relationship between strategic planning, the practical implementation of municipal services, and oversight processes. Specifically, thesis triangulates legislative mandates, documents published by Inxuba Yethemba Municipality (IYM) and responses from semi-structured interviews conducted with three municipal officials and three Municipal Public Accounts Committee (MPAC) councillors to uncover descriptions and explanations of service delivery processes in IYM. Findings from this thesis confirm that poor strategic planning and weak oversight contributed to poor electricity service delivery outcomes in IYM in the 2018/19 – 2019/20 financial year, and this highlights the importance of implementing strategic management for improved service delivery in South African local municipalities. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2022
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The governance of schools for internally displaced learners in Puntland, Somalia: a top-down or bottom-up approach to education peacebuilding?
- Authors: Ramaite, Adivhaho Florence
- Date: 2022-10-14
- Subjects: Peace-building Somalia Puntland , Internally displaced persons Education Somalia Puntland , School management and organization Somalia Puntland , Educational governance , Top-down and bottom-up design
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406807 , vital:70309
- Description: This study examines educational governance in schools for internally displaced learners in Puntland, Somalia. Many Somalis have been internally displaced from the south and central of Somalia and neighbouring regions because of armed insurgence, as well as climate and ecological disasters. Communities of internally displaced Somalis who have settled in the north-eastern region of Somalia, together with the Ministry of Education and nongovernmental organisations such as Relief International, have established schools for internally displaced learners. The study uses interviews with teachers, school principals and school committee members to examine their experiences of how schools are governed, specifically in terms of the bottom-up and top-down approaches to peacebuilding education. This research study is the first of its kind to examine the experiences of education actors in internally displaced person schools in Somalia. It provides crucial, new information on northern NGOs and how they shape the governance of knowledge and resources in Somali schools and how Somali education actors interpret and respond to these interventions. Drawing on education studies and international relations, it develops a transdisciplinary framing of peacebuilding education and specifically focuses on the top-down and bottom-up approaches to peacebuilding education provision. It weaves these two disciplinary perspectives together to help establish the implications of the security sector in education and broadly post-conflict reconstruction. The study finds that donors, international NGOs and government actors use a top-down approach to education, which may sit at odds with local needs and priorities. It finds that Somali knowledge and values are marginalised in the curriculum and teachers’ professional development and that the distribution of resources such as teacher salaries and school feeding programmes is fragmented, opaque and lacking in accountability. The study emphasises that the exclusion of local voices may further contribute to the causes underlying conflict. , Thesis (MA) -- Faculty of Humanities, Political and International Studies, 2022
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The impacts of anthropogenic fires in West African savanna woodlands and parklands: the case of the Guinea savanna, Ghana
- Authors: Amoako, Esther Ekua Amfoa
- Date: 2022-10-14
- Subjects: Firemaking Ghana , Agroforestry Ghana , Parks Fire management Ghana , Nature Effect of human beings on Ghana , Land use Ghana , Savanna ecology Ghana , Traditional ecological knowledge Ghana
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/365610 , vital:65764 , DOI https://doi.org/10.21504/10962/365610
- Description: Fire is recognised as an important factor influencing the structure and function of tropical savannas. Despite the extensive studies conducted on the effects of fire on global savannas, there are relatively few studies focusing on fire-assisted land use practices in the agroforestry parkland of the Sudano-Guinean savannas of West Africa. The region experiences recurrent fires in the dry season which begins from November to April. The fires are anthropogenic and are mainly caused through rural livelihoods and cultural practices such as farming - to remove debris from crop fields and to improve soil fertility and hunting to flush out animals, among other reasons. This study therefore sought to: 1. contribute to the understanding of fire-assisted traditional land use practices, people’s knowledge and perceptions of fire use and fire regime: 2. analyse the effects of fire on vegetation, and 3. determine the effects of fire on soils in the Guinea savanna woodlands and parklands of Ghana. Study sites (burnt and unburnt land use types) were selected based on five-year daily fire counts (2013-2017) data, obtained from the Earth Observation Research and Innovation Centre (EORIC), Ghana in collaboration with the Council for Scientific and Industrial Research (CSIR) Meraka Institute, South Africa. Fire densities were calculated for the 18 districts in the Guinea savanna (Northern Region of Ghana). The districts were stratified into low, medium and high fire frequency areas. The East Gonja district recorded the highest fire density (1.0 fires km-2) while Tamale recorded the lowest fire density (0.3 fires km-2). Of the eighteen districts, six districts were purposively selected and ten communities sampled. Firstly, I investigated the frequency of fire use and control, perceptions of fire regime for selected livelihood and socio-cultural activities in the six districts. The majority of respondents (83%) across the study districts indicated that they used fire once a year for at least one of the following activities: land preparation, weed/grass/pest control, burning stubble after harvest, bush clearing around homesteads, firebreaks, charcoal burning and hunting. The study showed the highest frequency of fire use in the dry season was for land preparation for cropping. However, less than a fifth of the respondents (17%) indicated that they did not use fire for any of the above activities. The results of a multiple regression predicted fire activities in the dry season from gender, age, level of education, occupation and household size. Secondly, the study examined how fire influenced the population structure and abundance of two economically important woody species Vitellaria paradoxa C. F. Gaertn. (Shea tree) and Anogeissus leiocarpa (DC.) Guill. & Perr. (African Birch) in burnt and unburnt land-use types. Stand basal area, mean densities of juveniles and adult trees and Simpson’s index of dominance were determined. Eight diameter size classes of each species were analysed by comparing their observed distributions to a three-parameter Weibull distribution across the land use types. A total of 3,366 individuals of A. leiocarpa (n = 1,846) and V. paradoxa (n = 1,520) were enumerated. The highest total basal area of Anogeissus leiocarpa (16.9 m2/ha) was estimated in sacred groves whereas Vitellaria. paradoxa (20.6 m2 /ha) was found in unburnt woodland. The highest mean densities of A. leiocarpa (22.7±29.7 stems/ha) and V. paradoxa (15.3±2.2 stems/ha) were found in sacred in groves. Anogeissus leiocarpa was, however, absent in fallows and burnt crop fields. A somewhat inverse J-shaped distribution was found in sacred groves for both species. Thirdly, the study compared species composition in early burnt, late burnt and unburnt plots in a protected area where fire was regulated. Vitellaria paradoxa C. F. Gaertn., Terminalia avicennioides Guill. & Perr., Combretum adenogonium Steud. ex A. Rich. and Combretum molle R. Br. Ex. G. Don. were the most common and abundant in all treatments. Late burnt and unburnt plots recorded the lowest diversity amongst the three treatments. Unburnt plots had higher tree density than burnt plots. A Detrended Canonical Analysis showed a changing trend, indicating a moderately strong positive association between burning time and species composition. The first and second axes contributed 53% and 12% variation, respectively. Most of the species found in axis one had fairly strong positive association to early and late burnt treatment than unburnt treatments. Finally, the effects of fire on soil properties in burnt and unburnt crop fields and woodland in the ten communities were also investigated. A total of 151 composite samples in selected burnt and unburnt land use types (burnt crop field n=20; unburnt crop field n=27; burnt woodland n=53, unburnt woodland n=51) were analysed. The variables analysed were pH, soil organic carbon (SOC), total nitrogen (TN), available phosphorous (P), Exchangeable bases - potassium (K), magnesium (Mg), calcium (Ca), cation exchange and soil texture. Total N, SOC, pH and Ca differed significantly across the burnt and unburnt land-use types. A principal component analysis showed a stronger association and more positive gradient in woodlands than in crop fields. Total N showed a positive association with SOC, whereas silt showed a negative association to sand and clay. Traditional knowledge and perceptions of users of savanna agroforestry parklands can inform the formulation of local by-laws for community fire management as well as national policy regulation on fire use in the savanna through the interlinked analysis of social and ecological systems as have been elucidated in this study. The results on vegetation assessment revealed that fire practices and land uses influenced size class distribution of the two study species as well as the densities of woody species in traditional crop fields and the National Park. The unstable populations observed in most land uses and the absence of A. leiocarpa in crop fields and fallows call for education and policy actions on the use of fire in parklands of West Africa. Furthermore, fires positively influenced some soil properties in both woodlands and crop fields confirming one of the emphasised reasons why rural subsistence farmers use fire. As an environmental management decision and land use policy intervention, early dry season burning could be an option to curbing the indiscriminate and unplanned fire use. Also, the protection of trees on farm lands could check the unstable population structure of economically important woody species leading to the different structures that deviated from the recommended reverse J-shaped distribution curve observed in these agroforestry parklands. The management of socio-ecological systems such as the agroforestry parklands of West Africa require a holistic understanding of the complexity of the different resource systems, units and actors involved for sustainable management of these natural resources. , Thesis (PhD) -- Faculty of Science, Environmental Science, 2022
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The implementation of a mobile application to decrease occupational sitting through goal setting and social comparison
- Authors: Tsaoane, Moipone Lipalesa
- Date: 2022-10-14
- Subjects: Sedentary behavior , Sitting position , Feedback , Mobile apps , Behavior modification , Agile software development
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/365544 , vital:65758
- Description: Background: Feedback proves to be a valuable tool in behaviour change as it is said to increase compliance and improve the effectiveness of interventions. Interventions that focus on decreasing sedentary behaviour as an independent factor from physical activity are necessary, especially for office workers who spend most of their day seated. There is insufficient knowledge regarding the effectiveness of feedback as a tool to decrease sedentary behaviour. This project implemented a tool that can be used to determine this. To take advantage of the cost-effectiveness and scalability of digital technologies, a mobile application was selected as the mode of delivery. Method: The application was designed as an intervention, using the Theoretical Domains Framework. It was then implemented into a fully functioning application through an agile development process, using Xam- arin.Forms framework. Due to challenges with this framework, a second application was developed using the React Native framework. Pilot studies were used for testing, with the final one consisting of Rhodes University employees. Results: The Xamarin.Forms application proved to be unfeasible; some users experienced fatal errors and crashes. The React Native application worked as desired and produced accurate and consistent step count readings, proving feasible from a functionality standpoint. The agile methodology enabled the developer to focus on implementing and testing one component at a time, which made the development process more manageable. Conclusion: Future work must conduct empirical studies to determine if feedback is an effective tool compared to a control group and which type of feedback (between goal-setting and social comparison) is most effective. , Thesis (MSc) -- Faculty of Science, Computer Science, 2022
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The incorporation of GeoGebra as a visualisation tool to teach calculus in teacher education institutions: the Zambian case
- Authors: Kangwa, Lemmy
- Date: 2022-10-14
- Subjects: GeoGebra , Calculus Study and teaching (Secondary) Zambia , Visual learning
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/405470 , vital:70174 , DOI
- Description: This qualitative case study investigated teacher educators’ (lecturers) use of the dynamic mathematics software, GeoGebra, to teach calculus in three teacher education institutions (TEIs) in Zambia. Visualisation, a key characteristic of GeoGebra, is increasingly gaining recognition of playing a critical role in mathematics teaching and learning, especially in problem solving tasks. It is considered a powerful didactical tool for students to construct mental and physical representations that can enhance conceptual understanding of mathematics. GeoGebra is a visualisation tool that can be used for problem-oriented teaching and foster mathematical experiments and discoveries. GeoGebra’s inherent visualisation characteristics align well with the teaching of calculus, the mathematical domain of this study. The study (whose research methodology was underpinned by the interpretive paradigm) was undertaken with a broader goal of designing and implementing GeoGebra applets and instructional materials on various calculus topics. The study is located within the “Teaching and Learning Mathematics with GeoGebra (TLMG) project” – a project that involves mathematics teachers and lecturers in Zambia. The case in this study is the six mathematics lecturers who co-designed and used GeoGebra applets to teach derivatives and integrals to pre-service mathematics teachers in TEIs. The unit of analysis therefore is the six lecturers’ use of GeoGebra as a visualisation tool to teach calculus to enhance conceptual understanding, their perceptions and experiences of using GeoGebra and the enabling and constraining factors of using GeoGebra to teach and learn mathematics. The data for the study were video recordings of observations and interviews of lecturers. The data was analysed thematically and was guided and informed by an analytical framework adopted from the theory of constructivism – the umbrella theoretical framework of this study – and the models of Technological Pedagogical Content Knowledge (TPACK), and the Technology Acceptance Model (TAM). A detailed analysis of the lecturers’ interactions with the applets enabled me to gain insights into the participants’ experiences and perceptions of GeoGebra applets in the teaching and learning process. The findings of the study revealed that the visualisation characteristics of GeoGebra generally enhanced the conceptual understanding of calculus. It also revealed that adequate training, coupled with sufficient knowledge of the subject matter in calculus, were necessary for lecturers to use GeoGebra effectively, and that the lack of resources and expertise were major hindrances in the use of GeoGebra to teach mathematics in TEIs. It also revealed that there is a need to equip GeoGebra with other features that would make it more versatile, and suggested a teaching approach that would complement the use of conventional methods and GeoGebra to provide a link between abstract and concrete concepts of calculus. , Thesis (PhD) -- Faculty of Education, Education, 2022
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The invisible teacher: The teacher envisaged in the Curriculum and Assessment Policy Statement (CAPS) English First Additional Language (EFAL) Further Education and Training (FET) Phase
- Authors: Dowejko, Diane Agnieszka
- Date: 2022-10-14
- Subjects: Educational sociology South Africa , Systemic functional linguistics , Curriculum-based assessment South Africa , Linguistic analysis (Linguistics) , Educational evaluation South Africa
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406714 , vital:70301
- Description: Educational policy documents, which are intended to enlighten teachers about what they should teach and how they should assess learners, contain both language and knowledge. How this knowledge is construed through language may reveal the kind of teacher envisaged by the document, and the assumptions made regarding the dispositions of these educators. There is a plethora of research on the relationship between the Curriculum and Assessment Policy Statement for English First Additional Language in the Further Education and Training Phase (CAPS-EFAL) and its impact on the learner in the classroom, but little evidence of research related to how curriculum documents envisage the teacher, and linguistic research pertaining to CAPS-EFAL. This research aims to use linguistic analysis to discover how the teacher is envisaged in this document, while speaking to the broader subject of the relationship between teacher and curriculum policy. This study adopts a framework which inspects this language using Systemic Functional Linguistics to analyse language in relation to its functions in social contexts, and the instructional knowledge built in CAPS-EFAL through applying elements of Legitimation Code Theory, analysing processes of knowledge production and recontextualisation. An investigation of the language revealed assumptions that the envisaged teacher is one who is already highly trained in aspects of language teaching and classroom methodology and pedagogy. While the analysis also revealed a high level of guidance for the teacher, there was a strong focus on the knowledge within the curriculum, and several assumptions made regarding the teacher’s prior knowledge before encountering or utilising the document. The analysis also revealed that CAPS-EFAL acknowledges that the teacher requires a sound knowledge of technical terminology related to language teaching, as well as general classroom pedagogies and routines. In addition, the document assumes that the disposition of the teacher is one who can make decisions without the need for absolute confirmation or authority from curriculum documentation. Overall, the analysis revealed an élite code in terms of Specialization; CAPS-EFAL is therefore based on the legitimacy of both specialised knowledge and the disposition of the teacher. , Thesis (MA) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2022
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